Pedro Arcos González

On the synthesis of functionalized cyclic and polymeric aryloxyphosphazenes from phenols

A very convenient synthetic method is described for the known cyclic aryloxyphosphazenes [N3P3(OC6H4-R)6] (R = Br, CN, CHO, COCH3, COC6H5, and NO2). The method is based on the direct reaction of [N3P3Cl6] with six equivalents of the para-substituted phenols HOC6H4-R and K2CO3 in refluxing acetone and is characterized by very short reaction times and very simple workups, leading directly to the analytically and spectroscopically pure products in very high yields. In the cases where R = H, But, or OCH3, the reactions were much slower, but the time could be shortened by using [Bu4N]Br as the phase-transfer catalyst. Similarly, the polymers [NP(OC6H4-R)2]n can be conveniently obtained in ca. 70% and good analytical purity from polydichlorophosphazene [NPCl2]n and the para-substituted phenols HOC6H5-R (R = Br, CN, COCH3, and NO2) in the presence of K2CO3 using THF as the solvent.

INFRARED AND RAMAN SPECTRA OF THE PHOSPHAZENE HIGH POLYMER NP(O2C12H8)N

The vibrational spectra of a new type of phosphazene polymer, [NP(O2C12H8)]n (polyspirophosphazene), are discussed. The spectra were recorded for powders dispersed in KBr pellets and for films prepared from different solvents. The IR spectra are dominated by the vibrational modes of the main chain whereas the Raman spectra are dominated by the vibrations of the peripheral biphenyl groups. The full width at half maximum (FWHM) of the Raman band at 1609 cm-1, corresponding to one of the CC stretching modes of the biphenyl, decreases with increase in the degree of crystallinity of the polymer sample.

Direct synthesis of cyclic and polymeric phosphazenes bearing diphenylphosphine groups and their complexes with [W(CO)5] fragments

Abstract The reactions of the cyclotriphosphazenes [N 3 P 3 Cl 6 ] or [N 3 P 3 (O 2 C 12 H 8 ) 2 Cl 2 ] with the phenolic phosphine PPh 2 (C 6 H 4 -OH) in the presence of Cs 2 CO 3 give, respectively, the cyclic phosphazene phosphines [N 3 P 3 (OC 6 H 4 PPh 2 ) 6 ] ( 1 ) and [N 3 P 3 (O 2 C 12 H 8 ) 2 (OC 6 H 4 PPh 2 ) 2 ] ( 2 ), very pure and in high yield. The similar reaction with the linear polyphosphazene {[NP(O 2 C 12 H 8 )] 0.65 [NPCl 2 ] 0.35 } n in THF gives the diphenylphosphine polymer {[NP(O 2 C 12 H 8 )] 0.65 [NP(OC 6 H 4 PPh 2 ) 2 ] 0.35 } n ( 3 ). The phenolic tungsten pentacarbonyl complex {W(CO) 5 [PPh 2 (C 6 H 4 -OH)]} reacts in the same way with those cyclic and polymeric phosphazenes to give the corresponding complexes {N 3 P 3 [OC 6 H 4 PPh 2 -W(CO) 5 ] 6 } ( 4 ), [N 3 P 3 (O 2 C 12 H 8 ) 2 (OC 6 H 4 PPh 2 -W(CO) 5 ) 2 ] ( 5 ), and {[NP(O 2 C 12 H 8 )] 0.65 [NP(OC 6 H 4 PPh 2 -W(CO) 5 ) 2 ] 0.35 } n ( 6 ).

Indicadores de riesgo de morbilidad prevenible causada por medicamentos

Objetivos: Los objetivos principales de este trabajo son: estudiar la frecuencia de los 43 indicadores de riesgo de morbilidad prevenible causada por medicamentos (RMPM), identificados previamente, en pacientes con tratamiento farmacologico que acuden a un servicio de urgencias hospitalario; describir las caracteristicas de los pacientes en los que estaba presente el indicador, y establecer si el motivo de consulta y la gravedad de los pacientes coinciden con alguna de las situaciones clinicas descritas en los indicadores. Metodo: Estudio observacional descriptivo transversal que utiliza la base de datos de un estudio multicentrico sobre prevalencia de resultados negativos de la medicacion en el Hospital Universitario Central de Asturias. Criterios de inclusion de pacientes: a) estar tomando un medicamento relacionado con las situaciones clinicas descritas en los indicadores; b) presentar una enfermedad relacionada con los indicadores de resultados de problemasrelacionados con medicamentos, y c) acudir a urgencias por un motivo relacionado con los indicadores. Resultados: Se estudiaron 436 pacientes. El perfil del paciente con indicador es una mujer mayor de 64 anos que utiliza cuatro o mas medicamentos. Cincuenta y siete pacientes (13,1%) presentaban alguna de las situaciones descritas en los indicadores. Un 28% tenia un indicador relacionado con AINE, un 26,3% con asma/EPOC, un 8,8% con osteoporosis y un 7% con uso dedigoxina y medicamentos psicotropos. El 68,4% de los pacientes con indicador mostraban una gravedad leve, un 7% moderada y un 19,3% grave. Conclusiones: Se hallaron 17 indicadores (39,5%) en 57 pacientes (13%) de los que acudieron al servicio de urgencias. En mas del 80% (46) de esos pacientes el motivo por el que acudierona urgencias fue presentar alguna situacion descrita en los indicadores. El 25% (14) de los pacientes con indicador presentaban una situacion grave y tuvieron que ser ingresados. Los pacientesdel grupo con indicador presente tenian mas edad, ingresaban mas y usaban mas medicamentos de media.

Synthesis and spectroscopic characterization of cyclic and polymeric phosphazenes bearing phosphine complexes

Abstract The reactions of the cyclic phosphazenes [N 3 P 3 Cl 6 ] and [N 3 P 3 (O 2 C 12 H 8 ) 2 Cl 2 ] (O 2 C 12 H 8 =2,2′-dioxybiphenyl) with the diphenylphosphine phenol complex {Mn(CO) 2 (η 5 -C 5 H 4 Me)[PPh 2 (C 6 H 4 OH)]} ( 1 ) and Cs 2 CO 3 in refluxing acetone gave, respectively the phosphazene–phosphine complexes {N 3 P 3 [OC 6 H 4 PPh 2 Mn(CO) 2 (η 5 -C 5 H 4 Me)] 6 } ( 2 ) and {N 3 P 3 (O 2 C 12 H 8 ) 2 [OC 6 H 4 PPh 2 Mn(CO) 2 (η 5 -C 5 H 4 Me)] 2 } ( 3 ), in good yields. The analogous reaction of the partially substituted clorophosphazene polymer {[NP(O 2 C 12 H 8 )] 0.6 [NPCl 2 ] 0.4 } n in THF gave the polymeric complex [{NP(O 2 C 12 H 8 )} 0.6 {NP[OC 6 H 4 PPh 2 Mn(CO) 2 (η 5 -C 5 H 4 Me)] 2 } 0.4 ·0.5[OC 4 H 8 ] n ( 4 ). Different spectroscopic data are provided for the new compounds that may be useful for the characterization of other more complex polymeric materials.

Solution properties of polyphosphazenes containing 2,2′-dioxybiphenyl groups

Abstract Dilute solution properties of four different polyphosphazenes containing 2,2′-dioxybiphenyl groups have been studied by size exclusion chromatography, using simultaneously multiangle light scattering and differential refractive index detectors. The polymers present broad molecular weight distributions and the dependence of the dimensions, i.e. radius of gyration, of the polymers on the molecular weight is discussed. Moreover, scaling laws and unperturbed dimensions have been calculated for the fractions with high molecular weight. The polymers behave as random coil chains, the characteristic ratios are in the range 12–17 in good accord with the results reported for other polyphosphazenes.

On the presence of polytetrahydrofuran in the polyspiro-phosphazenes [NP(O2C12H8)]n prepared from [NPCl2]n and 2,2′-dihydroxybiphenyl in THF as solvent

Polydichlorophosphazene [NPCl2]n reacts with the diphenol 2,2′-(HO)C6H4-C6H4(OH) in THF in the presence of K2CO3 to give the polymers [NP(O2C12H8) · x(OC4H8)]n (1) that contain variable ammouts of polytetrahydrofuran (PTHF) with x ranging from 0.05 to 0.8. This PTHF content (x) depends on the method followed to prepare the THF solutions of [NPCl2]n used for the reactions with the biphenol and can be made negligibly small, forming these solutions in the presence of K2CO3. This reveals the presence in the [NPCl2]n of acidic species capable of catalyzing the ring opening polymerization of THF. Polyphosphazene [NP(O2C12H8)]n (2) was prepared completely free of PTHF using dioxane as solvent. A comparison of the thermal behavior and morphological data of the polymers 1, 2, PTHF (5), and mixtures of [NP(O2C12H8)]n + x(OC4H8)m (4) revealed that the products 1 are strongly interacting polymer blends and ruled out the possibility of block copolymers.

The Lebanese-Syrian crisis: impact of influx of Syrian refugees to an already weak state.

Background Lebanon, a small Middle Eastern country facing constant political and national unity challenges with a population of approximately 300,000 Palestinian and Iraqi refugees, has welcomed more than 1.2 million Office of the United Nations Commissioner for Refugees (UNHCR)-registered Syrian refugees since 2012. The Government of Lebanon considers individuals who crossed Lebanese–Syrian borders since 2011 as “displaced”, emphasizing its long-standing position that Lebanon is not a state for refugees, refusing to establish camps, and adopting a policy paper to reduce their numbers in October 2014. Humanitarian response to the Syrian influx to Lebanon has been constantly assembling with the UNHCR as the main acting body and the Lebanon Crisis Response Plan as the latest plan for 2016. Methods Review of secondary data from gray literature and reports focusing on the influx of Syrian refugees to Lebanon by visiting databases covering humanitarian response in complex emergencies. Limitations include obtaining majority of the data from gray literature and changing statistics due to the instability of the situation. Results The influx of Syrian refugees to Lebanon, an already weak and vulnerable state, has negatively impacted life in Lebanon on different levels including increasing demographics, regressing economy, exhausting social services, complicating politics, and decreasing security as well as worsened the life of displaced Syrians themselves. Conclusion Displaced Syrians and Lebanese people share aggravating hardships of a mutual and precarious crisis resulting from the Syrian influx to Lebanon. Although a lot of response has been initiated, both populations still lack much of their basic needs due to lack of funding and nonsustainable program initiatives. The two major recommendations for future interventions are to ensure continuous and effective monitoring and sustainability in order to alleviate current and future suffering in Lebanon.

Desastres y salud pública: un abordaje desde el marco teórico de la epidemiología

Durante la decada 1990-2000 los desastres (catastrofes) causaron cada ano una media de 75.000 muertes, afectaron a una media anual de 256 millones de personas y causaron perdidas economicas por valor de mas de 650.000 millones de euros. La magnitud del problema, su impacto sobre la salud publica y sobre el nivel de desarrollo de las poblaciones afectadas es de tal importancia que se justifica un particular interes desde el punto de vista de la salud publica, especialmente con la aparicion de las denominadas emergencias complejas. El objetivo de este trabajo es revisar las definiciones, los conceptos fundamentales y las caracteristicas basicas de la epidemiologia de los desastres. Se analizan tambien los factores de riesgo de los desastres, los efectos sobre la salud publica de los principales tipos de desastres y las principales estrategias preventivas en funcion de las diferentes fases del ciclo de un desastre.

The Perceived Barriers of Access to Health Care Among a Group of Non-camp Syrian Refugees in Jordan:

The aims of this study were to identify the most needed health care services, accessibility of various health care services, and barriers to access as perceived by a group of Syrian refugees living in non-camp settings in Jordan and to compare accessibility among different groups. The study was conducted in the Amman, Irbid, Karak, and Maan governorates of Jordan. This is a cross-sectional, analytical, observational study using convenience and snowball sampling for data collection. A structured questionnaire was included in an ongoing needs assessment of a Jordanian nongovernment organization in April 2014, with a total of 196 surveys conducted. In addition to the prevalent acute and communicable diseases, chronic diseases and dental problems were common. Preventive and primary health care were more accessible than advanced services. Structural and financial barriers hindered access. The specific survey location and governorate were associated with a difference in reported access. Registration status, health provider, duration, and out-of-pocket payment did not affect accessibility. The capacities of health facilities at different levels should be increased. Enhanced information sharing among health providers can improve identification of needs and gaps.