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The classic Troger's base polymerization of a diamine and dimethoxymethane with trifluoroacetic acid as catalyst generated a Troger's base-type polymer (TBP), which exhibited the absolute insolubility in a variety of organic solvents because of its highly aggregated model. A new porous organic polymer was obtained by a simple Troger's base polymerization reaction between a diamine and formaldehyde in the form of acetal in the presence of trifluoroacetic acid as catalyst. Troger's base-type polymer (TBP) resulted insoluble in a wide range of organic solvents due to its rigid and aromatic structure. TBP was characterized spectroscopically (FT-IR), thermally and morphologically. As result, a thermostable and amorphous polymer bearing pores ranging between 50 and 300 nm and macro-voids of up to 12 μm was obtained. Due to the insolubility of the TBP, it was tested as a metal-free heterogeneous catalyst in the Knoevenagel condensation reaction, showing a high efficiency. For this, the optimal catalyst load, reaction time and reuse of the catalyst were studied using benzaldehyde and malononitrile as substrates. Furthermore, aldehydes with variable chain sizes and ethyl cyanoacetate replacing malononitrile were tested as substrate with a high percent of conversion (97–99%).

Two new silicon-containing poly(azomethine)s (PAzM-Me and PAzM-Ph) and two new silicon-containing poly(p-phenylvinylene)s (PPVSi-Me and PPVSi-Ph) were obtained from 4′,4′''-(dimethylsilanediyl)bis([1,1′-biphenyl]-4-carbaldehyde) and 4′,4′''-(diphenyl silanediyl)bis([1,1′-biphenyl]-4-carbaldehyde) with p-phenylendiamine for PAzMs or phenylenebis(methylene))bis(triphenylphosphonium) bromide for PPVSis. All polymers were structurally characterized by FT-IR, NMR and elemental analysis. The materials showed a high thermal stability (501–538 °C) with the TPS-core increasing this parameter. The absorption and emission of PAzMs and PPVSis were closely related with the nature of the silane-core in the backbone. All samples showed wide-band gaps where the TPS-core-based materials evidenced the lower energy transitions; PAzM-Ph (2.83 eV) and PPVSi-Ph (2.81 eV). This work lay the groundwork for new architectures of silane-based poly(azomethine)s and poly(p-phenylvinylene)s derivatives for potential optoelectronic applications.

In the search of new photoactive materials for light-emitting applications, two new germanium-based oligourethanes (PUGe-27 and PUGe-28) were synthesized from 4,4-(diphenylgermarylene)bis(phenyl chloroformate) (1) and dibenzo[b,d]furan-2,7-diamine (2) or 4,4′-(dibenzo[b,d]furan-2,8-diyl)dianiline (3) through pyridine-catalysed polycondensation. The structural characterization of the oligourethanes was performed by elemental analysis (EA), IR and NMR techniques. All oligomers were soluble in common organic solvents including THF, which was used to prepare brittle films by casting method. Molecular weights were established in the range of 4.5–5.0 kDa by SEC measures. The samples exhibited a TDT10% in the range of 307–351 °C, while Tg showed values near to 220 °C. Thermal behavior differences were consistent with the molecular flexibility’s degree provided by the monomeric diamine. Suitable absorption and emission behavior were displayed for both germanium-based oligourethanes with moderate Stokes shifts. PUGe-28 showed a strong fluorescence in the blue region of the visible light (364 nm). Both PUGes had wide-band gap (3.76 eV) with interesting high-lying LUMO levels (ac. 2.04 eV). To better understand the experimental results, DFT and TD-DFT calculations were carried out. The results obtained could be used as a guide for future research on Ge-based PUs as photoactive materials.

The aim of this study was to compare three cooling management systems to improve the physiological status and lactation performance of Holstein cows during summer heat. Multiparous Holstein cows, 32, were blocked according to milk yield divided into four treatments being: C) Control group, cows cooled before milking time (0500 and 1700 h daily); AM) cows cooled at 1100 h and before milking; PM) cows cooled at 2300 h and before milking; and AM + PM) cows cooled at 1100 and 2300 h, as well as before milking. Total cooling time per group was 1 h for the Control group, 2 h for AM and PM groups, and 3 h for the AM + PM group. Cows were moved to a holding pen daily to be cooled. Respiration rate (RR) and rectal temperatures (RT) were lowered ( P P P

Introduccion Se presenta la experiencia de un hospital universitario terciario urbano en el diseno e implementacion de una unidad de hospitalizacion a domicilio (UHaD) integrada en un Servicio de Medicina Interna y altamente coordinada con los servicios medicos del hospital y la Atencion Primaria de salud del entorno hospitalario, que contempla como principales objetivos la promocion de la atencion especializada domiciliaria de patologias medicas y la mejora de la coordinacion con la Atencion Primaria de salud. Pacientes y metodos Recogida sistematica en todos los pacientes ingresados entre abril 2006 y marzo 2007 en la UHaD de las siguientes variables: edad, sexo, lugar y servicio de procedencia, diagnostico principal, indice de Barthel y de Charlson, numero de visitas al dia de enfermeria y medicas, destino al alta y equipo medico responsable. El analisis estadistico descriptivo se realizo en abril de 2007. Los resultados se presentan de forma global y diferenciados por equipos (Medicina Interna, Neumologia y soporte nutricional). Resultados Quinientos seis ingresos que correspondian a 390 pacientes con una edad media de 66,5 (18) anos, y un 53% mujeres. El indice de Charlson fue de 2 (2,2) y el indice de Barthel de 63,5 (40,4). La estancia media fue de 7,9 (8,2) dias. Los principales motivos de ingreso fueron las infecciones y tratamiento antibiotico por via intravenosa en 153 (30,5%) casos, las agudizaciones de enfermedad pulmonary obstructiva cronica o insuficiencia cardiaca en 107 (21%) casos y la nutricion enteral o parenteral domiciliaria en 102 (20%) casos. Doscientos (39,5%) pacientes al finalizar el ingreso fueron controlados por sus equipos de Atencion Primaria, 241 (47,5%) fueron seguidos en consultas del hospital y 45 (9%) retornaron directamente al hospital. Conclusion La creacion de una UHaD para patologias medicas desde el Servicio de Medicina Interna, altamente coordinada con servicios medicos del hospital, especialmente con Urgencias, Neumologia y Soporte Nutricional y con la Atencion Primaria del entorno hospitalario, facilita la atencion especializada domiciliaria de patologias medicas y mejora la coordinacion con la Atencion Primaria de salud.