Quantum cascade lasers monolithically integrated on germanium.

Silicon (Si) photonics can have a major impact on the development of mid-IR photonics by leveraging on the reliable and high-volume fabrication technologies already developed for microelectronic integrated circuits. Germanium (Ge), already used in Si photonics, is a prime candidate to extend the operating wavelength of Group IV-based photonic integrated circuits beyond 8 µm, and potentially up to 15 µm. High performance quantum cascade lasers (QCLs) and interband cascade lasers grown on Si have been demonstrated, whereas no QCLs monolithically integrated on Ge have been reported yet. In this work, we present InAs-based QCLs directly grown on Ge by molecular beam epitaxy. The lasers emitting near 14 µm exhibited threshold current densities as low as 0.8-0.85 kA/cm2 at room temperature.

Carrier dynamics in (Ga,In)(Sb,Bi)/GaSb quantum wells for laser applications in the mid-infrared spectral range.

We present experimental studies on low-temperature ([Formula: see text]) carrier dynamics in (Ga,In)(Sb,Bi)/GaSb quantum wells (QWs) with the nominal In content of 3.7% and the Bi ranging from 6 to 8%. The photoreflectance experiment revealed the QW bandgap evolution with [Formula: see text] % Bi, which resulted in the bandgap tunability roughly between 629 and [Formula: see text], setting up the photon emission wavelength between 1.97 and [Formula: see text]. The photoluminescence experiment showed a relatively small 3-10[Formula: see text] Stokes shift regarding the fundamental QW absorption edge, indicating the exciton localisation beneath the QW mobility edge. The localised state's distribution, being the origin of the PL, determined carrier dynamics in the QWs probed directly by the time-resolved photoluminescence and transient reflectivity. The intraband carrier relaxation time to the QW ground state, following the non-resonant excitation, occurred within 3-25[Formula: see text] and was nearly independent of the Bi content. However, the interband relaxation showed a strong time dispersion across the PL emission band and ranging nearly between 150 and [Formula: see text], indicating the carrier transfer among the localised state's distribution. Furthermore, the estimated linear dispersion variation parameter significantly decreased from [Formula: see text] to [Formula: see text] with increasing the Bi content, manifested the increasing role of the non-radiative recombination processes with Bi in the QWs.

Localized surface plasmon resonance frequency tuning in highly doped InAsSb/GaSb one-dimensional nanostructures.

We report a detailed analysis of the influence of the doping level and nanoribbon width on the localized surface plasmon resonance (LSPR) by means of reflectance measurements. The plasmonic system, based on one-dimensional periodic gratings of highly Si-doped InAsSb/GaSb semiconductor nanostructures, is fabricated by a simple, accurate and large-area technique fabrication. Increasing the doping level blueshifts the resonance peak while increasing the ribbon width results in a redshift, as confirmed by numerical simulations. This provides an efficient means of fine-tuning the LSPR properties to a target purpose of between 8-20 µm (1250-500 cm(-1)). Finally, we show surface plasmon resonance sensing to absorbing polymer layers. We address values of the quality factor, sensitivity and figure of merit of 16 700 nm RIU(-1) and 2.5, respectively. These results demonstrate Si-doped InAsSb/GaSb to be a low-loss/high sensitive material making it very promising for the development of biosensing devices in the mid-infrared.

III-V-on-silicon integrated micro - spectrometer for the 3 µm wavelength range.

A compact (1.2 mm2) fully integrated mid-IR spectrometer operating in the 3 µm wavelength range is presented. To our knowledge this is the longest wavelength integrated spectrometer operating in the important wavelength window for spectroscopy of organic compounds. The spectrometer is based on a silicon-on-insulator arrayed waveguide grating filter. An array of InAs0.91Sb0.09 p-i-n photodiodes is heterogeneously integrated on the spectrometers output grating couplers using adhesive bonding. The spectrometer insertion loss is less than 3 dB and the waveguide-referred responsivity of the integrated photodiodes at room temperature is 0.3 A/W.

Silicon-on-insulator shortwave infrared wavelength meter with integrated photodiodes for on-chip laser monitoring.

This paper demonstrates a very compact wavelength meter for on-chip laser monitoring in the shortwave infrared wavelength range based on an optimized arrayed waveguide grating (AWG) filter with an integrated photodiode array. The AWG response is designed to obtain large nearest neighbor crosstalk (i.e. large overlap) between output channels, which allows accurately measuring the wavelength of a laser under test using the centroid detection technique. The passive AWG is fabricated on a 220 nm silicon-on-insulator (SOI) platform and is combined with GaInAsSb-based photodiodes. The photodiodes are heterogeneously integrated on the output grating couplers of the AWG using DVS-BCB adhesive bonding. The complete device with AWG and detectors has a footprint of only 2 mm(2) while the measured accuracy and resolution of the detected wavelength is better than 20pm.

Rat vas deferens SERCA2 is modulated by Ca2+/calmodulin protein kinase II-mediated phosphorylation.

Ca2+ pumps are important players in smooth muscle contraction. Nevertheless, little information is available about these pumps in the vas deferens. We have determined which subtype of sarco(endo)plasmic reticulum Ca2+-ATPase isoform (SERCA) is expressed in rat vas deferens (RVD) and its modulation by calmodulin (CaM)-dependent mechanisms. The thapsigargin-sensitive Ca2+-ATPase from a membrane fraction containing the highest SERCA levels in the RVD homogenate has the same molecular mass (∼115 kDa) as that of SERCA2 from the rat cerebellum. It has a very high affinity for Ca2+ (Ca0.5 = 780 nM) and a low sensitivity to vanadate (IC50 = 41 µM). These facts indicate that SERCA2 is present in the RVD. Immunoblotting for CaM and Ca2+/calmodulin-dependent protein kinase II (CaMKII) showed the expression of these two regulatory proteins. Ca2+ and CaM increased serine-phosphorylated residues of the 115-kDa protein, indicating the involvement of CaMKII in the regulatory phosphorylation of SERCA2. Phosphorylation is accompanied by an 8-fold increase of thapsigargin-sensitive Ca2+ accumulation in the lumen of vesicles derived from these membranes. These data establish that SERCA2 in the RVD is modulated by Ca2+ and CaM, possibly via CaMKII, in a process that results in stimulation of Ca2+ pumping activity.

Silicon-on-insulator spectrometers with integrated GaInAsSb photodiodes for wide-band spectroscopy from 1510 to 2300 nm.

We present a silicon-on-insulator (SOI) based spectrometer platform for a wide operational wavelength range. Both planar concave grating (PCG, also known as echelle grating) and arrayed waveguide grating (AWG) spectrometer designs are explored for operation in the short-wave infrared. In addition, a total of four planar concave gratings are designed to cover parts of the wavelength range from 1510 to 2300 nm. These passive wavelength demultiplexers are combined with GaInAsSb photodiodes. These photodiodes are heterogeneously integrated on SOI with benzocyclobutene (DVS-BCB) as an adhesive bonding layer. The uniformity of the photodiode characteristics and high processing yield, indicate a robust fabrication process. We demonstrate good performance of the miniature spectrometers over all operational wavelengths which paves the way to on-chip absorption spectroscopy in this wavelength range.

Rat vas deferens SERCA2 is modulated by Ca2+/calmodulin protein kinase II-mediated phosphorylation

Ca2+ pumps are important players in smooth muscle contraction. Nevertheless, little information is available about these pumps in the vas deferens. We have determined which subtype of sarco(endo)plasmic reticulum Ca2+-ATPase isoform (SERCA) is expressed in rat vas deferens (RVD) and its modulation by calmodulin (CaM)-dependent mechanisms. The thapsigargin-sensitive Ca2+-ATPase from a membrane fraction containing the highest SERCA levels in the RVD homogenate has the same molecular mass (∼115 kDa) as that of SERCA2 from the rat cerebellum. It has a very high affinity for Ca2+ (Ca0.5 = 780 nM) and a low sensitivity to vanadate (IC50 = 41 µM). These facts indicate that SERCA2 is present in the RVD. Immunoblotting for CaM and Ca2+/calmodulin-dependent protein kinase II (CaMKII) showed the expression of these two regulatory proteins. Ca2+ and CaM increased serine-phosphorylated residues of the 115-kDa protein, indicating the involvement of CaMKII in the regulatory phosphorylation of SERCA2. Phosphorylation is accompanied by an 8-fold increase of thapsigargin-sensitive Ca2+ accumulation in the lumen of vesicles derived from these membranes. These data establish that SERCA2 in the RVD is modulated by Ca2+ and CaM, possibly via CaMKII, in a process that results in stimulation of Ca2+ pumping activity.

Amorphous calcium carbonate biomineralization in the earthworm's calciferous gland: pathways to the formation of crystalline phases.

In this study, we investigated the microstructural transformations that take place during carbonate formation in the earthworm's calciferous gland by analysing the evolution from the precursor fluid of the solid phases (spherulites) to the final carbonate concretions released by the gland. Results from HREM and electron diffraction showed that the spherulithic deposits merely consisted of ACC partially transformed to vaterite. Furthermore, comparisons of the diffraction spectra and microstructural analyses allowed the identification of the transition sequences to more stable carbonates. And thus, transformations of ACC to calcite were observed on the surfaces of these amorphous globular aggregates as their smooth characteristic surface became rougher with time. This transition path was not unique, and the presence of aragonite, as an intermediate phase, has also been found. In this particular case, the transition process followed a completely different pathway with the crystallization starting in the centre of the sphere and progressively extending to the periphery, leading to the formation of radial aggregates. In situ experiments performed on the freshly extracted precursor fluid and analysed by FT-IR spectroscopy showed that ACC is the main constituent and is probably stabilised by macromolecules such as proteins and sugars. Furthermore, the Debye-Scherrer diffraction experiments showed that the carbonate phase present in this fluid remains stable as ACC for more than a week. All these features are indicative of this entire process being biologically controlled by the earthworms. The analysis of the amorphous structure factor of this ACC indicates that these transformations are preceded by short-range order modifications of the amorphous precursor phase.

Autonomía y estado de salud percibidos en ancianos institucionalizados / Autonomy and health status perceived by elderly institutionalised people

El ingreso en residencias ha sido denominado con el concepto de institucionalización, para diferenciarlo de la atención comunitaria y denotar su carácter de especialización. Los ancianos válidos al ingreso en un centro dejan de realizar tareas por un mecanismo de ajuste de su conducta a la vez que pueden adoptar una actitud pasiva; efecto generador de dependencia. Todos los ancianos al ingresar por primera vez en un centro geriátrico se someterán a un período de adaptación y observación establecido en 20 días tras el cual será valorado por una comisión técnica. En un estudio anteriormente realizado en la misma población se pudo constatar, refiriéndonos a la capacidad funcional traducida en AVD e AIVD y a la percepción de la salud de los residentes, durante los primeros 20 días de ingreso (período de adaptación), que los resultados muestran la existencia de una relación significativa entre la autonomía e independencia de un anciano y su deterioro debido a la institucionalización, a la vez se deduce que los mayores durante dicho período de adaptación no sufren cambios significativos en su percepción de salud por el hecho de la institucionalización, si bien es cierto que dicho período es sólo de 20 días según la Legislación sobre Servicios Sociales en Andalucía y no hay tiempo suficiente para evidenciar los cambios. Al creer necesario un seguimiento más a largo plazo, se pretende hacer una segunda valoración de los aspectos anteriormente mencionados y medidos tras pasar un período lo suficientemente amplio (año y medio) como para poder constatar si persiste o no el deterioro en la autonomía e independencia de los mayores para la realización de actividades de la vida diaria e instrumentales, así como si se mantiene su percepción de salud. Objetivo: Evaluar la influencia que ejerce la institucionalización en la autonomía de un anciano en el momento de su ingreso en una residencia geriátrica de válidos y compararlo con el obtenido tras año y medio de institucionalización. Método: Diseño pre-experimental con estudio pretest-postest de un solo grupo en dos momentos diferentes, es decir, medición previa y posterior a una intervención, que en este caso sería el tiempo. Variables dependientes: Grado de Autonomía: Medir la capacidad del anciano/a referente a actividades cotidianas mediante el Índice de Barthel, Actividades Básicas dela Vida Diaria (ABVD) y el de Lawton, Actividades Instrumentales de la Vida Diaria (AIVD). Variable Independiente: Ingreso del anciano/a en la Institución. Es la variable que pueda modificar o no su grado de autonomía. Variables sociodemográficas: Edad, sexo, procedencia, estado civil, capacidad adquisitiva, motivo de ingreso. Conclusiones: Dentro de una institución el programa de adaptación del anciano debería tener como prioridad la adaptación organizativa del centro a las verdaderas necesidades de los usuarios, no al revés, implicando en este proceso siempre a la familia… todo en pro de fomentar en todo momento la autonomía tanto física como psicológica del anciano

The admission to a residence has been termed “institutionalization ”in order to differentiate it from community care and to emphasize its nature as a specialisation. On admission to a centre, old people who are not invalid cease to perform certain tasks due to an adjustment process, which can result in passive behaviour; this in turn creates dependency. All old people, when enter a geriatric centre for the first time, undergo a period of adaptation and observation that lasts 20 days, after which they are evaluated by a technical committee. In a study previously made in the same population it was possible to be stated, referring us to the translated functional capacity in AVD and AIVD and to the perception of the health of the residents, during the first 20days of entrance (period of adaptation) that the results show the existence of a significant relation between the autonomy and independence of an old person and a its deterioration due to the institutionalization, simultaneously it is deduced that the elder during this period of adaptation do not undergo significant changes in their perception of health by the fact of the institutionalization, although is certain that this period is only of 20 days according to the Legislation of the Social Services in Andalusia and that is not enough time to demonstrate the changes. Believing necessary a pursuit but in the long term, we tried to make a second valuation of the aspects previously mentioned and measured after passing a sufficiently ample period (year and a half) like being able to state if the deterioration persists or not in the autonomy and independence of the elderly people to perform daily life and instrumental activities, as well as if their perception of health stays. Objective: To evaluate the influence of institutionalization on an old person’s autonomy on admittance to a geriatric residence for non-invalids, and the comparison with their behaviour after the period of a year and a half of institutionalization. Methods: A pre-experimental design with a pre- and posttest study of a single group during two different periods, that is to say, a measurement before and after of an intervention which in this case is defined as time. Dependent variables: Level of Autonomy. To measure the capacity of an old person in relation to everyday activities using the Barthel Scale (ABVD) Basic Activities of Daily Life; and the Lawton Scale (AIVD) Instrumental Activities of Daily Life. Independent variable: Admission of the old person into the Institution. This is the variable that could modify, or otherwise, the level of autonomy. Socio-demographic variables: Age; sex; background; civil status; acquisitive capability; reason for admission. Conclusions: Within the programme of adaptation in an institution, priority must be given to the organizational adaptation of the centre to the needs of the users and not the contrary. The user’s family should be involved as much as possible in order to preserve the physical and psychological autonomy of the old person at all times

Specific molecular targets to control tropical diseases.

Chagas' disease or American trypanosomiasis is considered by the Word Health Organization to be one of the important tropical parasitic diseases worldwide together with malaria and schistosomiasis. The etiologic agent of this illness is the kinetoplastid protozoon Trypanosoma cruzi. The present chemotherapy for the treatment of Chagas' disease remains unsolved. The drugs currently in use are old, ineffective and toxic. Bearing in mind the metabolic differences between the parasite and the mammalian host, some attractive interesting molecular targets for drug design are presented.

Valoración de los informes médicos recibidos del segundo nivel / Evaluation of the medical reports received from the second care level

Objetivos. Cuantificar la tasa de interconsulta mensual (TIM), porcentaje de informes médicos recibidos, calidad de éstos y tiempo de demora de la primera consulta al segundo nivel. Diseño. Estudio descriptivo, transversal. Emplazamiento. Centro de salud rural. Muestra. Las 498 primeras consultas solicitadas al segundo nivel de 3 cupos de médicos de familia desde junio a noviembre de 1999. Se excluyeron 132 por presentar algún criterio de exclusión (consultas entre el segundo nivel, revisiones, consultas a las que el paciente no acudió y aquellas que no se pudieron registrar), quedando un tamaño muestral de 366 (n).Mediciones y resultados. La TIM media fue del 34 . Los servicios de oftalmología (21,9 por ciento), ginecología (15,3 por ciento) y traumatología (13,9 por ciento) fueron los más solicitados. Se recibieron 69 informes (18,8 por ciento), quedando 297 (81,2 por ciento) sin recibir. Los servicios de neumología (100 por ciento) y medicina interna (81,8 por ciento) fueron los que más informes remitieron, mientras que hematología y rehabilitación (0 por ciento) fueron los que menos. La puntuación media de los informes fue de 8 ñ 2 sobre un máximo de 10. La demora media fue de 73 ñ 46 días. Conclusión. La TIM se encuentra entre los valores descritos en la bibliografía. El porcentaje de informes recibidos es muy inferior a lo hallado en la bibliografía, pero su calidad es buena (AU)

Bisphosphonates derived from fatty acids are potent growth inhibitors of Trypanosoma cruzi.

We have investigated the effect of a series of bisphosphonates derived from fatty acids against Trypanosoma cruzi proliferation in in vitro assays. Some of these drugs proved to be potent inhibitors against the intracellular form of the parasite exhibiting IC50 values at the low micromolar level. As bisphosphonates are FDA clinically approved for treatment of bone resorption, their potential innocuousness makes them good candidates to control tropical diseases.

[Triage area. Use and effectiveness of a protocol]. / Area de "triage". Utilidad y eficacia de un protocolo.

In the Organization of the urgency services, there's a general agreement about need to have a triage system or a first classification of the patient at their arrival, for a quick, ordered, and directed access, attending the dangerously wounded patient with priority, acting like a true filter of the dangerously wounded patient. This is a function realized in The Juan Ramon Jimenez Hospital by nurses in the triage area. Patient is classified into these groups, determining of this way the priority of their attention, basing in the triage protocol: I: emergency or vital risks. II: acute processes, critical. III: acute processes, no critical. IV: banal processes, no urgent. The objective of this study is to evaluate the utility and efficacy of the nurse triage protocol from the valuation of different nurses, compiling data of 300 clinic histories, taking as indicative or evaluations, the degree of homogeneity of the differents triages realized. We take from a comparative description study of a total of 300 cases, being cassified in a continuous way by two nurses in different areas. To emphasize, that of the total of the studied population, the percentage of patients that have been classified with the same gravity level by both nurses, is about the 95.9%, being located the not coincidences, always in levels iii and iv. the 99.7% of these patients have been derived to the same speciality atter their triage. The specialities that sustain greater assistance demand are internal medicine and traumatology, with a 41.7% and a 34.3% respectively. The total of studied cases, 75% attend to the urgency service by own petition, which 86% are catalogued as level iv (banal processes), 23.4% are transmitted by urgency services or provide p10, being only a 20% of theses cases considered as acute processes, that it supposes a 4.6% of the total and a 1.3% are transferred by e.p.e.s 061, being the 100% defined as acute processes. The group of age that demand more sanitary assistance is between 20 and 40 years, prevailed the masculine sex in all the groups, except in those greater of 60 years, where the women exceed them in a 23.6%.

La oxigenoterapia en situaciones graves

La oxigenoterapia es una medida de soporte vital indicada en todo paciente que se encuentre en estado crítico, cuyo objetivo es garantizar las necesidades de oxígeno de los tejidos.Los sistemas de administración de oxígeno más empleados son las gafas nasales, las mascarillas tipo venturi y las mascarillas con reservorio. Según las características y gravedad del cuadro clínico al que nos enfrentamos nos decantaremos por uno u otro.La utilización de este arma terapéutica siempre lleva implícita una ulterior comprobación de su eficacia. Para ello nos basaremos en parámetros clínicos, gasométricos y pulsioximetría (AU)

"Area de Triage". Utilidad y eficacia de un protocolo / Triage Area

Introducción. En la organización del área de urgencias es necesario contar con un sistema de clasificación inicial de pacientes procurando un acceso rápido, ordenado y dirigido, atendiendo con prioridad a los de mayor gravedad. Esta función es realizada en el Hospital Juan Ramón Jiménez de Huelva por el personal de enfermería dentro de la denominada Área de Triage. El enfermo es clasificado en cuatro niveles: IV: procesos banales, no urgentes. Ill: procesos agudos, no críticos. II: procesos agudos, criticos. l: emergencia o riesgo vital. Objetivo. Evaluar la utilidad y eficacia del Protocolo de Triage de Enfermería a partir de la valoración por distintos enfermeros de 300 historias clínicas. Estudio descriptivo comparativo de un total de 300 casos, siendo seleccionados de forma continua por dos enfermeros en áreas distintas. Resultados. El porcentaje de enfermos que han sido clasificados con el mismo nivel de gravedad por ambos enfermeros, es del 95,9 por ciento, localizándose las no coincidencias, siempre en niveles III y IV El 99,7 por ciento de estos enfermos han sido derivados a la misma especialidad tras su valoración. Del total de casos estudiados el 75,3 por ciento acuden al Área de Urgencias por petición propia, de las cuales el 86 por ciento son catalogados como nivel IV. Conclusiones. La clasificación de pacientes que realiza enfermería en el Hospital Juan Ramón Jiménez de Huelva es válida desde el punto de vista del indicador estudiado, dado que el grado de concordancia al valorar la mayoría de H.C. en niveles de gravedad y en especialidades que se derivan es considerablemente bueno, índices Kappa 0,85 por ciento y 0,99 por ciento respectivamente (AU)

Design and synthesis of aryloxyethyl thiocyanate derivatives as potent inhibitors of Trypanosoma cruzi proliferation.

As a part of our project directed at the search of new chemotherapeutic agents against American trypanosomiasis (Chagas' disease), several drugs possessing the 4-phenoxyphenoxy skeleton and other closely related structures employing the thiocyanate moiety as polar end group were designed, synthesized, and evaluated as antiproliferative agents against Trypanosoma cruzi, the parasite responsible for this disease. These thiocyanate analogues were envisioned bearing in mind the potent activity shown by 4-phenoxyphenoxyethyl thiocyanate (compound 8) taken as lead drug. This compound had previously proved to be an extremely active growth inhibitor against T. cruzi with IC(50) values ranging from the very low micromolar level in epimastigotes to the low nanomolar level in the intracellular form of the parasite. Of the designed compounds, the ethyl thiocyanate drugs connected to nonpolar skeletons, namely, arylthio, 2,4-dichlorophenoxy, ortho-substituted aryloxy, and 2-methyl-4-phenoxyphenoxy (compounds 15, 34, 47, 52, 72, respectively), were shown to be very potent antireplicative agents against T. cruzi. On the other hand, conformationally restricted analogues as well as branched derivatives at the aliphatic side chain were shown to be moderately active against T. cruzi growth. The biological activity of drugs bearing the thiocyanate group correlated quite well with the activity exhibited by their normal precursors, the tetrahydropyranyl ether derivatives, when bonded to the same nonpolar skeleton. Compounds having the tetrahydropyranyl moeity as polar end were proportionally much less active than sulfur-containing derivatives in all cases. Drugs 47 and 72 also resulted to be very active against the amastigote form of the parasite growing in myoblasts; however, they were slightly less active than the lead drug 8. On the other hand, compounds 34 and 52 were almost devoid of activity against myoblasts. Surprisingly, the dithio derivative 15 was toxic for myoblasts.

Sulphur-containing derivatives structurally related to fenoxycarb are potent growth inhibitors against the intracellular form of Trypanosoma cruzi.

Sulphur-containing derivatives structurally related to the insect growth regulator fenoxycarb were shown to be extremely active antiproliferative agents against the amastigote form of Trypanosoma cruzi in in vitro assays. All of these drugs had previously been proved to be remarkably potent growth inhibitors against the epimastigote form of the parasite.

Las heridas superficiales

La atención de pacientes heridos es extraordinariamente frecuente en las consultas de Medicina General y en los Servicios de Urgencias tanto hospitalarios como extrahospitalarios. Sin embargo, paradójicamente muchas veces nuestra formación teórica en este aspecto es escasa.Para su manejo, salvo en situaciones especiales que se caractericen por su alto grado de urgencia, se empezará realizando una adecuada historia del paciente y posteriormente de la herida que padece. A continuación se realizará su exploración y por último se procederá a la manipulación, que consistirá, por este orden, en el control de la hemorragia, la limpieza de la herida, el desbridamiento, el cierre y la protección de todo lo anteriormente realizado (AU)

Synthesis of C-5'-nor-dideoxycarbanucleosides structurally related to neplanocin C.

Purine carbanucleosides built on a 6-oxabicyclo[3.1.0]hexane template were synthesized from readily available 2-cyclopentenone employing a Mitsunobu reaction to incorporate the base onto the carbocyclic ring. Both adenosine and guanosine analogues exhibited moderate antiviral activity.