155 research outputs found
CorrecciĂłn de consolidaciĂłn viciosa diafisaria de fĂ©mur: osteotomĂa en caparazĂłn. A propĂłsito de dos casos.
La adecuada alineaciĂłn del miembro inferior es esencial para el adecuado reparto de cargas que
permita una deambulaciĂłn sin alteraciones. Por lo que a la hora del tratamiento de fracturas de huesos largos del
miembro inferior, fundamentalmente fémur y tibia, habrå que evitar cualquier deformidad angular que a medio
plazo provoque fenĂłmenos degenerativos en las articulaciones adyacentes. Se presentan dos casos clĂnicos complejos,
en los que se corrigieron sendas consolidaciones viciosas de fracturas diafisarias de fémur satisfactoriamente,
mediante osteotomĂa tipo caparazĂłn o clamshellThe lower limb alignment is essential to share correctly the bearing weight of the body to allow
a suitable gait. We should take it into account when treating femoral and tibial diaphyseal fractures, in order to
avoid angular deformities which could lead to degenerative changes in adjacent joints. We report two complex
cases, with femoral shaft malunions corrected satisfactorily by using a clamshell osteotom
Hysteretic nonequilibrium Ising-Bloch transition
We show that a parametrically driven cubic-quintic complex Ginzburg-Landau
equation exhibits a hysteretic nonequilibrium Ising-Bloch transition for large
enough quintic nonlinearity. These results help to understand the recent
experimental observation of this pheomenon [A. Esteban-Martin et al., Phys.
Rev. Lett. 94, 223903 (2005)].Comment: 3 pages + six figure
Phase-locking of a Nonlinear Optical Cavity via Rocking: Transmuting Vortices into Phase Patterns
We report experimental observation of the conversion of a phase-invariant
nonlinear system into a phase-locked one via the mechanism of rocking [G. J. de
Valcarcel and K. Staliunas, Phys. Rev. E 67, 026604 (2003)]. This conversion
results in that vortices of the phase-invariant system are being replaced by
phase patterns such as domain walls. The experiment is carried out on a
photorefractive oscillator in two-wave mixing configuration.A model for the
experimental device is given that reproduces the observed behavior.Comment: 9 pages and 4 figure
Cavity solitons in bidirectional lasers
We show theoretically that a broad area bidirectional laser with slightly
different cavity losses for the two counterpropagating fields sustains cavity
solitons (CSs). These structures are complementary, i.e., there is a bright
(dark) CS in the field with more (less) losses. Interestingly, the CSs can be
written/erased by injecting suitable pulses in any of the two
counterpropagating fields.Comment: 4 figure
Modular total syntheses of thymifodioic/incanic acids
The first total synthesis of the bioactive natural product 2,6-(E,E)-thymifodioic acid, also called incanic acid, and its stereoisomers is described. An unified, iterative and modular strategy was envisioned, achieving the synthesis of the goals products after five reaction steps in an overall yield ranging from 8% to 16%. The key step is a non-expensive easy to perform HornerâWadsworthâEmmons condensation.Fil: Ălvarez MĂ©ndez, Sergio J.. Universidad de la Laguna. Departamento de QuĂmica OrgĂĄnica. Instituto Universitario de Bio-OrgĂĄnica "Antonio GonzĂĄlez"; EspañaFil: Saad, JosĂ© Roberto. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - San Luis. Instituto de Investigaciones en TecnologĂa QuĂmica. Universidad Nacional de San Luis. Facultad de QuĂmica, BioquĂmica y Farmacia. Instituto de Investigaciones en TecnologĂa QuĂmica; ArgentinaFil: Tonn, Carlos Eugenio. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - San Luis. Instituto de Investigaciones en TecnologĂa QuĂmica. Universidad Nacional de San Luis. Facultad de QuĂmica, BioquĂmica y Farmacia. Instituto de Investigaciones en TecnologĂa QuĂmica; ArgentinaFil: MartĂn, VĂctor S.. Universidad de la Laguna. Departamento de QuĂmica OrgĂĄnica. Instituto Universitario de Bio-OrgĂĄnica "Antonio GonzĂĄlez"; EspañaFil: GarcĂa, Celina. Universidad de la Laguna. Departamento de QuĂmica OrgĂĄnica. Instituto Universitario de Bio-OrgĂĄnica "Antonio GonzĂĄlez"; Españ
Cardiovascular diseases and apical periodontitis : association not always implies causality
Several studies published in the last two decades have found an association between the prevalence of apical periodontitis (AP) or root canal treatment (RCT) and cardiovascular diseases (CVDs). However, the demonstration of association does not prove by itself the existence of a cause?effect relationship. Two diseases can appear as statistically related without any of them directly affecting the values of the other, resulting in a non-causal relationship. The aim of this narrative review is to summarize the current state of knowledge regarding the association between AP and CVDs, analysing it according to the Hill's causality criteria. Epidemiological studies carried out on the association between CVDs and AP or RCT published in English until 8 December 2019 were identified. Forty-four articles were selected and its results were analysed. Numerous cross-sectional epidemiological studies have found significant relationship between CVDs and AP. The odds ratio values range 1.6 - 5.4. However, other studies have not found significant association. Respect to RCT, some studies found correlation, but others found no association or even found that RCT is a protective factor against CVDs. The results are inconsistent and a causal relationship between CVDS and endodontic disease cannot be stablished. The risk factors common to both diseases can act as confounding factors, biasing the results. To reach definitive conclusions about the type of association (causal or non-causal) between both diseases, longitudinal epidemiological studies must be carried out to establish the temporal relationship and the dose-response gradient
Preliminary results on the application of the aminoacid racemization technique in the Murcia Region (SE Iberian Peninsula) and their interest in paleoseismological research
Geochronology is a critical issue in paleoseismological research. The
aminoacid racemization technique shows important advantages respect to
more traditional dating methods; not just for the lower costs and promptness,
also because the object to analyze is relatively frequent, in this study:
terrestrial gastropods. Furthermore, the costs of the analysis are by far faster
and cheaper compared to other dating techniques. Racemization results
allow comparing the relative age from different sedimentary units from one
trench to another.Additionally, the racemization technique can also be used
as a geochronological tool, provided a calibration curve has been first
obtained for the particular climate for the area and, ideally, for a particular
genus. In this study we show the results obtained from the analysis of 40
samples of terrestrial gastropods from 7 different trenches located in the
Murcia Region (SE Spain). Making use of the D/L ratio of aspartic acid we
show the coherence found between relative stratigraphic ages and the
racemization age. Finally, we show a provisional conversion equation
between age of racemization, obtained from Torres et al. (1997) algorithm,
and the likely age of the samEl control geocronolĂłgico es una cuestiĂłn crĂtica en los estudios de
paleosismologĂa. La tĂ©cnica de racemizaciĂłn de aminoĂĄcidos ofrece
importantes ventajas respecto a otros métodos de datación, tanto en los
costes y rapidez, como en la facilidad de encontrar el objeto de anĂĄlisis; en
este estudio, gasterĂłpodos terrestres. Los resultados permiten comparar la
edad relativa entre unidades sedimentarias diferentes de unas zanjas a otras.
La técnica de racemización también es una herramienta geocronológica, si
bien es necesario primero establecer una curva de calibraciĂłn para el
ambiente climåtico de la zona e, idealmente, para un género concreto. En
este estudio se muestran los resultados obtenidos en 40 muestras de
gasterĂłpodos terrestres recogidas en 7 zanjas de investigaciĂłn
paleosismolĂłgica en la RegiĂłn de Murcia. Haciendo uso de la relaciĂłn D/L
del ĂĄcido aspĂĄrtico mostramos la coherencia entre las edades relativas
estratigrĂĄficas y su edad de racemizaciĂłn. Finalmente, proponemos una
relaciĂłn provisional de conversiĂłn entre las edades de racemizaciĂłn
obtenidas por el algoritmo de Torres et al. (1997) para gasterĂłpodos de la
zona central de la PenĂnsula IbĂ©rica y la edad probable de las muestra
The MIS 5 palaeoenvironmental record in the SE Mediterranean coast of the Iberian Peninsula (RĂo Antas, AlmerĂa, Spain)
Se realiza un estudio detallado del episodio cĂĄlido MIS 5 en la zona sureste de la PenĂnsula IbĂ©rica. Se realiza la reconstrucciĂłn paleoambiental a partir del estudio polĂnico y biomarcadores de un sondeo perforado en la costa de AlmerĂa. La cronologĂa se estableciĂł a partir del mĂ©todo de racemizaciĂłnd e aminoĂĄcidos.Landwards of a MIS5 bar, a borehole core (SRA) was analyzed to establish the relationship between the lagoonal record and the raised beach deposits in the surroundings of the Antas river mouth and to reconstruct the Pleistocene palaeoenvironmental evolution 5 of the southern Mediterranean coast of the Iberian Peninsula. 63 samples were recovered for amino acid racemization dating, 86 samples for sedimentological and paleontological determination, 37 samples for pollen identification and 54 for biomarker analysis. AAR revealed that the borehole record contains MIS11, MIS6 and MIS5 deposits, the latter extensively represented. During the end of MIS6 and MIS5, a sand 10 barrier developed and created a shallow lagoon with alternating terrestrial inputs this process being common in other Mediterranean realms. Litho- and biofacies allowed the identification of distinct paleoenvironments through time, with the presence of a lagoonal environment alternating with alluvial fan progradation. Biomarkers indicated constant input from terrestrial plants, together with variable development of aquatic 15 macrophytes. The palynological content allowed the reconstruction of the paleoclimatological conditions during MIS6 and 5, with evidence of seven scenarios characterized by alternating arid and relatively humid condition
Primeros resultados sobre la aplicaciĂłn de la tĂ©cnica de racemizaciĂłn de aminoĂĄcidos en la RegiĂłn de Murcia (SE de la PenĂnsula IbĂ©rica) y su interĂ©s en estudios de paleosismologĂa
Geochronology is a critical issue in paleoseismological research. The aminoacid racemization technique shows important advantages respect to more traditional dating methods; not just for the lower costs and promptness, also because the object to analyze is relatively frequent, in this study: terrestrial gastropods. Furthermore, the costs of the analysis are by far faster and cheaper compared to other dating techniques. Racemization results allow comparing the relative age from different sedimentary units from one trench to another.Additionally, the racemization technique can also be used as a geochronological tool, provided a calibration curve has been first obtained for the particular climate for the area and, ideally, for a particular genus. In this study we show the results obtained from the analysis of 40 samples of terrestrial gastropods from 7 different trenches located in the Murcia Region (SE Spain). Making use of the D/L ratio of aspartic acid we show the coherence found between relative stratigraphic ages and the racemization age. Finally, we show a provisional conversion equation between age of racemization, obtained from Torres et al. (1997) algorithm, and the likely age of the samples. RESUMEN: El control geocronolĂłgico es una cuestiĂłn crĂtica en los estudios de paleosismologĂa. La tĂ©cnica de racemizaciĂłn de aminoĂĄcidos ofrece importantes ventajas respecto a otros mĂ©todos de dataciĂłn, tanto en los costes y rapidez, como en la facilidad de encontrar el objeto de anĂĄlisis; en este estudio, gasterĂłpodos terrestres. Los resultados permiten comparar la edad relativa entre unidades sedimentarias diferentes de unas zanjas a otras. La tĂ©cnica de racemizaciĂłn tambiĂ©n es una herramienta geocronolĂłgica, si bien es necesario primero establecer una curva de calibraciĂłn para el ambiente climĂĄtico de la zona e, idealmente, para un gĂ©nero concreto. En este estudio se muestran los resultados obtenidos en 40 muestras de gasterĂłpodos terrestres recogidas en 7 zanjas de investigaciĂłn paleosismolĂłgica en la RegiĂłn de Murcia. Haciendo uso de la relaciĂłn D/L del ĂĄcido aspĂĄrtico mostramos la coherencia entre las edades relativas estratigrĂĄficas y su edad de racemizaciĂłn. Finalmente, proponemos una relaciĂłn provisional de conversiĂłn entre las edades de racemizaciĂłn obtenidas por el algoritmo de Torres et al. (1997) para gasterĂłpodos de la zona central de la PenĂnsula IbĂ©rica y la edad probable de las muestras
Tourism income and economic growth in Greece: Empirical evidence from their cyclical components
This paper examines the relationship between the cyclical
components of Greek GDP and international tourism income for
Greece for the period 1976â2004. Using spectral analysis the authors
find that cyclical fluctuations of GDP have a length of about nine
years and that international tourism income has a cycle of about
seven years. The volatility of tourism income is more than eight
times the volatility of the Greek GDP cycle. VAR analysis shows that
the cyclical component of tourism income is significantly influencing
the cyclical component of GDP in Greece. The findings support the
tourism-led economic growth hypothesis and are of particular
interest and importance to policy makers, financial analysts and
investors dealing with the Greek tourism industry
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