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1.
F1000Res ; 9: 584, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-35673520

RESUMO

Background: Health systems strengthening (HSS) and health security are two pillars of universal health coverage (UHC). Investments in these areas are essential for meeting the Sustainable Development Goals and are of heightened relevance given the emergence of the 2019 novel coronavirus disease (COVID-19). This study aims to generate information on development assistance for health (DAH) for these areas, including how to track it and how funding levels align with country needs. Methods: We developed a framework to analyze the amount of DAH disbursed in 2015 for the six building blocks of the health system ('system-wide HSS') plus health security (emergency preparedness, risk management, and response) at both the global (transnational) and country level. We reviewed 2,427 of 32,801 DAH activities in the Creditor Reporting System (CRS) database (80% of the total value of disbursements in 2015) and additional public information sources. Additional aid activities were identified through a keyword search. Results: In 2015, we estimated that US$3.1 billion (13.4%) of the US$22.9 billion of DAH captured in the CRS database was for system-wide HSS and health security: US$2.5 billion (10.9%) for system-wide HSS, mostly for infrastructure, and US$0.6 billion (2.5%) for system-wide health security. US$567.1 million (2.4%) was invested in supporting these activities at the global level. If responses to individual health emergencies are included, 7.5% of total DAH (US$1.7B) was for health security. We found a correlation between DAH for HSS and maternal mortality rates, and we interpret this as evidence that HSS aid generally flowed to countries with greater need. Conclusions : Achieving UHC by 2030 will require greater investments in system-wide HSS and proactive health emergency preparedness. It may be appropriate for donors to more prominently consider country needs and global functions when investing in health security and HSS.

2.
Chemphyschem ; 21(2): 149-153, 2020 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-31777135

RESUMO

We demonstrate that weak CH⋅⋅⋅O hydrogen bonds (HBs) are important host-guest interactions in zeolite assemblies involving structure directing organocations. This type of HB is identified between alkyl groups of the organic structure directing agent (OSDA) and the silica framework in as-synthesized silicalite-1 of complex topology (MFI) using a combination of experimental and theoretical data obtained at low and room temperatures. The 28 weak CH⋅⋅⋅O HBs, evidenced along dynamics simulation at room temperature, represent 30 % of the energy of the Coulomb electrostatic interaction between OSDA and the zeolite framework. The strongest and most stable HB found here connects the OSDA to the [41 52 62 ] cage containing F atoms and should contribute to preserve zeolite topology during crystal growth. An inspection of other as-synthesized zeolites of very different framework topology indicates that the directional CH⋅⋅⋅O HBs have to be considered when discussing zeolite structure directing phenomena.

3.
Phys Chem Chem Phys ; 15(45): 19870-8, 2013 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-24145744

RESUMO

Solid materials possessing basic properties are naturally covered by carbonates and hydroxyl groups. Those natural adsorbates modify their chemical reactivity. This article aims to specifically evidence the role of surface carbonates and hydroxyls in basic heterogeneous catalysis on MgO. It compares the catalytic behaviors of hydroxylated or carbonated MgO surfaces for two types of reactions: one alkene isomerization and one alcohol conversion (hept-1-ene isomerization and 2-methyl-3-butyn-2-ol conversion). Catalysis experiments showed that carbon dioxide adsorption poisons the catalyst surface and the DRIFT-DFT combination showed that the nature of active sites in the two reactions differs. On the reverse, partial hydroxylation of the surface enhances activity for both reactions. Interestingly hept-1-ene isomerization gives a volcano curve for the conversion as a function of hydroxyl coverage. Calculations of the electronic structure of magnesium oxide surfaces show that neither Lewis basicity nor Brønsted basicity of the surface defects (steps for example) are enhanced by hydroxylation. Meanwhile CO2 adsorption followed by IR spectroscopy shows that (110) and (111) unstable planes are strongly basic and are stabilized by partial surface hydroxylation. These results could explain the volcano curve obtained for the evolution of alkene isomerisation as a function of hydroxyl coverage.


Assuntos
Carbonatos/química , Hidróxidos/química , Óxido de Magnésio/química , Adsorção , Álcoois/química , Alcenos/química , Dióxido de Carbono/química , Catálise , Concentração de Íons de Hidrogênio , Hidroxilação , Modelos Moleculares , Conformação Molecular , Propriedades de Superfície
4.
J Colloid Interface Sci ; 408: 87-93, 2013 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-23916158

RESUMO

This study deals with the ionically-driven self-assembly of oligomeric aminosilicones, judiciously protonated with a variety of organic acids. Depending on the length of the silicone and the strength of the associated acids, (inverse) water-in-silicone emulsions, small nanoparticles, or catanionic vesicles were prepared and characterized by conventional (TEM) or original (DIC optical microscopy, DOSY NMR) techniques. For chains longer than about 40 units, a specific PEG-based sulfonic acid was synthesized and used to generate a supramolecular block-like copolymer and ensure fast and efficient emulsification. In all instances, a simple impulse such as pH increase triggered phase separation of the colloidal objects.


Assuntos
Silicones/química , Água/química , Espectroscopia de Ressonância Magnética , Microscopia Eletrônica de Transmissão , Prótons
5.
Angew Chem Int Ed Engl ; 50(35): 8062-6, 2011 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-21751310

RESUMO

Vibrations of the metal active site of the Cu,Zn-superoxide dismutase enzyme were analyzed by far-infrared difference spectroscopy and theoretical normal mode calculation. Both electrochemically triggered Cu(I) and Cu(II) redox states show well-defined infrared vibrational modes, notably modes of the histidine ligands, the Cu(II)-His(61)-Zn(II) bridge and of the water pseudo-ligand.


Assuntos
Superóxido Dismutase/química , Domínio Catalítico , Cobre/química , Histidina/química , Ligantes , Oxirredução , Espectroscopia de Infravermelho com Transformada de Fourier , Superóxido Dismutase/metabolismo , Água/química
6.
Phys Chem Chem Phys ; 12(44): 14740-8, 2010 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-20944858

RESUMO

A set of CaO samples was prepared from thermal decomposition of several precursors, leading to very different surface properties. During storage, CaO samples rehydrated quickly but reversibly. Before characterization, the samples were pre-treated at 1023 K under nitrogen flow to obtain CaO as the active phase. Although this pre-treatment led to almost the same specific surface areas for all samples, their basic reactivity levels toward 2-methylbut-3-yn-2-ol conversion were different from one preparation to another. In contrast with the properties of MgO pre-treated at the same temperature, the basic reactivity of CaO correlates neither with the concentration of surface defects (exposing ions in low coordination) determined by photoluminescence nor with the deprotonation ability toward methanol. In order to identify the active sites on CaO pre-treated under nitrogen in the temperature range 673 K-1023 K, OH groups were quantified with (1)H NMR: the higher the surface density of OH groups, the higher the basic reactivity. Even after pre-treatment at 1023 K, after which only a few hydroxyls remain, the basic reactivity is governed by the remaining hydroxylation of the surface. The higher reactivity of OH groups of CaO compared to those of Ca(OH)(2) and MgO is discussed.

7.
J Phys Chem B ; 113(45): 15119-27, 2009 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-19831393

RESUMO

Recent reports on proteins and related models show that vibrational spectroscopy in the far-infrared domain is a promising technique to characterize metal sphere coordination in proteins. The low-frequency modes are however complex, and there is a need to develop the analysis of metal sites by means of quantum chemical calculations as a support for useful interpretation of the far-IR data. In this study, we determined vibrational properties for systems containing Cu(II)-N(Imidazole) interactions present in many biological complexes by means of quantum chemical calculations and confronted the normal mode description with available experimental data. Analysis of the [Cu(histamine)]2+ complex led us to conclude that the anharmonic contributions are negligible in the far-IR domain. Geometry optimizations and vibrational frequency calculations of [Cu(hm)]2+ and [Cu(hm)2(ClO4)2] complexes were compared using various hybrid DFT functionals and basis sets. These investigations stressed the need of potential energy distribution calculations (PED) to assign the vibrational modes, to obtain an overall description of the vibration modes, and to efficiently compare the methods. Comparison of calculation methods with the B3LYP/6-31+G(d,p) and B3LYP/6-311+G(2d,2p) methods and with available experimental data showed that the B3LYP/6-31G(d,p) level of theory provides accurate predictions of the normal mode frequencies and assignments. These comparisons also enlighten that theoretical investigations of 2H- and 65Cu-labeled [Cu(hm)2(ClO4)2] complexes give with a very good accuracy the band shifts of the labeled copper-histamine derivatives. The theoretical calculations combined with experimental data allowed us to predict and calculate with good accuracy the values and assignments of the low-frequency IR modes, notably those involving metal contribution.


Assuntos
Cobre/química , Histamina/química , Modelos Químicos , Espectrofotometria Infravermelho , Vibração , Ligantes
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