El rasgo de personalidad "Búsqueda de sensaciones": una teoría psicobiológica

En este trabajo se expone y se sintetiza la teoría del rasgo de personalidad denominado "búsqueda de sensaciones", se proporciona información cronológica de la investigación empírica realizada desde los años 60 hasta nuestros días. Se incide en los correlatos biológicos de este rasgo en particular Potenciales Evocados (PE), Monoaminoxidades Plaquetear (MAO), Reflejo Orienativo (RO) y hormonas sexuales como la Testosterona (T) y Estradiol (E2). Se sugiere que se avance en la investigación psicobiológica del rasgo en cuestión, esfuerzo que por otro lado está generando un importante soporte empírico a la teoría.

Psicopatología de la desinhibición: un modelo para el estudio de la psicopatía

En este artículo se hace referencia a un modelo analógico para el estudio de los síndromes de la conducta desinhibida en humanos, denominado "Psicopatología de la Desinhibición". Este modelo propone una similitud entre las manifestaciones de conducta de humanos desinhibidos y los animales con lesión septal, sugiriendo de forma hipotética qué irregularidades en el sistema límbico podrían ser el sustrato biológico de estos síndromes entre los que es prototípico la psicopatología.

Diagnostic and Prognostic Impact of pc-ASPECTS Applied to Perfusion CT in the Basilar Artery International Cooperation Study.

BACKGROUND AND PURPOSE: The posterior circulation Acute Stroke Prognosis Early CT Score (pc-APECTS) applied to CT angiography source images (CTA-SI) predicts the functional outcome of patients in the Basilar Artery International Cooperation Study (BASICS). We assessed the diagnostic and prognostic impact of pc-ASPECTS applied to perfusion CT (CTP) in the BASICS registry population. METHODS: We applied pc-ASPECTS to CTA-SI and cerebral blood flow (CBF), cerebral blood volume (CBV), and mean transit time (MTT) parameter maps of BASICS patients with CTA and CTP studies performed. Hypoattenuation on CTA-SI, relative reduction in CBV or CBF, or relative increase in MTT were rated as abnormal. RESULTS: CTA and CTP were available in 27/592 BASICS patients (4.6%). The proportion of patients with any perfusion abnormality was highest for MTT (93%; 95% confidence interval [CI], 76%-99%), compared with 78% (58%-91%) for CTA-SI and CBF, and 46% (27%-67%) for CBV (P < .001). All 3 patients with a CBV pc-ASPECTS < 8 compared to 6/23 patients with a CBV pc-ASPECTS ≥ 8 had died at 1 month (RR 3.8; 95% CI, 1.9-7.6). CONCLUSION: CTP was performed in a minority of the BASICS registry population. Perfusion disturbances in the posterior circulation were most pronounced on MTT parameter maps. CBV pc-ASPECTS < 8 may indicate patients with high case fatality.

Comment on reversal of hypogonadotropic hypogonadism in a Chinese cohort.

The reversal of congenital hypogonadotropic hypogonadism (CHH) is a relatively recent phenomenon that has gained increasing attention over the past 10 years. Yet to date, only one prospective study has been conducted estimating that 10% (95% confidence interval [CI]: 2%-18%) of cases undergo reversal. [1] Other retrospective studies have reported rates in the range of 5%-8% [2],[3] and a recent study showed 44/308 (14%, 95% CI: 11%-19%) CHH patients underwent reversal. [4] Moreover, a time-to-event analysis in this large cohort revealed a lifetime reversal incidence of 22%. The article by Mao and colleagues presented in this issue is a meaningful contribution to our understanding of reversal as it examines the largest retrospective cohort to date. [5] Interestingly, they report the rate of reversal as 5% (95% CI: 3%-8%) in this Chinese cohort. It is difficult to reconcile the discrepancies in rates of reversibility and direct comparisons are hampered by the variable definitions employed. Using a novel definition for reversal (i.e, either endogenous testosterone (T) >270 ng dl−1 , serum T gradually increasing above 150 ng dl−1 with increased testicular volume, or normal spontaneous sperm production/normal erectile function/ejaculation), Mao and colleagues posit that testicular size and triptorelin-stimulated LH levels are reliable predictive factors for reversal. However, these cannot be considered as hard and fast rules for predicting reversal as the groups intersect - akin to the overlap observed between CHH patients and those with delayed puberty. Indeed, the fact that approximately half (44%, 95% CI: 25%-66%) of the reversal patients in the study by Mao et al.[5] were diagnosed between 17 and 19 years of age, underscores the challenge in differentiating CHH from extreme normal variants of puberty. This study further lends credence the recently reported observations that reversals may relapse. [4],[6] The notion that reversal may not be lasting highlights the vulnerability of the reproductive axis among CHH patients. While the mechanism(s) for relapse are unclear, it seems plausible that environmental, metabolic or psychiatric stressors could contribute. The factors that Mao and colleagues identify as significantly different in cases of reversal, were not informative for identifying those cases that relapsed back to a hypogonadal state. Notably, reversal has been reported in probands harboring mutations in genes underlying CHH. [1],[3],[4],[6] Unfortunately, comprehensive genetic screening on the Chinese cohort is not available. The reversal phenomenon is fascinating for its glimpse into the plasticity of the neuroendocrine control of reproduction. Future directions will almost certainly include investigation of specific genetic signatures and novel biomarkers for predicting reversal (and relapse). Yet CHH is a rare condition and to fully elucidate the biology of reversible CHH, it will be important to harmonize definitions of what constitutes a reversal, carefully phenotype patients and chart the natural history of their CHH. In this way, this unique human disease model may offer further insights into the control of human reproduction and provide opportunities to translate discoveries into enhanced approaches to improve the care and quality of life for these patients.

Cerebral Hypoperfusion in Posterior Reversible Encephalopathy Syndrome is Different from Transient Ischemic Attack on CT Perfusion.

BACKGROUND: PRES is a reversible neurotoxic state presenting with headache, altered mental status, visual loss, and seizures. Delayed diagnosis can be avoided if radiological patterns could distinguish PRES from cerebral ischemia. METHODS: Clinical and radiological data were collected on all hospitalized patients who had (1) discharge diagnosis of PRES and (2) acute CTP/CTA. Data were compared with 10 TIA patients with proven cytotoxic edema on MRI. RESULTS: Of the four PRES patients found, three were correlated with acute blood pressure and one with chemotherapy. At the radiological level, quantitative analyses of the CTP parameters showed that 2 out of 4 patients had bilaterally reduced CBF-values (23.2-47.1 ml/100g/min) in occipital regions, as seen in the pathological regions of TIA patients (27.3 ± 13.5 ml/100g/min). When compared with TIA patients, the pathological ROI's demonstrated decreased CBV-values (3.4-5.6 ml/100g). Vasogenic edema on MRI FLAIR imaging was seen in only one PRES patient, and cytotoxic edema on DWI-imaging was never found. CT angiography showed in one PRES patient a vasospasm-like unilateral posterior cerebral artery. CONCLUSIONS: If confirmed by other groups, CTP and CTA imaging in patients with acute visual loss and confusion may help to distinguish PRES from bi-occipital ischemia. These radiological parameters may identify PRES patients at risk for additional tissue infarction.

Localized prostate cancer in Norway, the United States, and Spain: between-country differences of variables before treatment among patients eligible for curative treatment

Between-country differences in medical and sociodemographic variables, and patient-related outcomes (PROs) before treatment might explain published variations of side effects after radical prostatecomy (RP) or radiotherapy (RAD) for prostate cancer (PCa). This hypothesis was tested among 1908 patients from the United States, Spain, and Norway. Significant between-country differences were observed for most factors investigated before treatment. The observations should be considered in comparison of the frequency and severity of internationally published studies. Background: In men with PCa, large variations of PROs after RP or high-dose RAD might be related to betweencountry differences of medical and sociodemographic variables, and differences in PROs before treatment in the sexual and urinary domains. Patients and Methods: In 1908 patients with localized PCa from Norway, the United States, or Spain, the relation between medical (prostate-specific antigen, Gleason score, cT-category) and sociodemographic variables (age, education, marital status) before treatment was investigated. Using the Expanded Prostate Cancer Index Composite questionnaire, PROs before treatment within the sexual and urinary domains were also considered. Results: Compared with the European patients, American patients were younger, fewer had comorbid conditions, and more had a high education level. Fifty-three percent of the US men eligible for RP had low-risk tumors compared with 42% and 31% among the Norwegian and the Spanish patients, respectively. Among the Spanish RAD patients, 54% had had low-risk tumors compared with 34% of the American and 21% of the Norwegian men planned for RAD, respectively. Compared with the European patients, significantly fewer US patients reported moderate or severe sexual dysfunction and related problems. In most subgroups, the number of patients with sexual or urinary dysfunction exceeded that of patients with bother related to the reported dysfunction. Conclusion: Statistically significant between-country differences were observed in medical and sociodemographic variables, and in PROs before treatment within the sexual and urinary domains. Large differences between reported dysfunction and related problems within the sexual and urinary domains indicate that dysfunction and bother should be reported separately in addition to calculation of summary scores. The documented differences, not at least regarding PROs, might in part explain the large variation of side effects after treatment evident in the medical literature

Consideraciones sobre la transitividad en la Sombra del viento : efectos estilísticos

La popular novela de Carlos Ruiz Zafón La sombra del viento contiene un gran número de oraciones que responden a un mismo patrón estructural: un elemento con el rasgo semántico [–animado] aparece al inicio de la oración y funciona como primer argumento de un proceso material (representado por un verbo) que en principio tiene que vincularse con elementos que tienen el rasgo semántico [+animado]. El modelo de transitividad que propuso M. A. K. Halliday sirve de guía metodológica a este artículo, que parte del planteamiento central de que, en la novela, la disposición de los componentes lingüísticos sea usada como un mecanismo estilístico. Así, el uso constante de la estructura adquiere tal importancia que acaba por revolucionar la dimensión estética de la realidad novelada en su totalidad. Una estructura que sitúa a determinados elementos léxicos en una posición de relevancia estilística y colabora en que esas estructuras puedan participar simultáneamente en más de un nivel de generación de significado.

Para além das fronteiras da química: relações entre filosofia, psicologia e ensino de química

The concepts of molecule and of molecular structure are so central to understand chemical phenomena that seems to be no doubt about the uniqueness of its meanings. Nevertheless, the idea that the world exhibits a multiform structure and that to different spheres of the world correspond different ways of knowing (Berger & Luckmann, 1967) has received support from different areas of scientific inquiry. Bachelard (1940, 1982) showed that a single philosophical doctrine is not enough to describe all the different ways of thinking when we try to explain a single concept. Wooley's question about the possibility of deducing the concept of molecular structure from quantum theory (Wooley, 1978) strengthened the feasibility of thinking the concept of molecule as a profile that encompasses different meanings. Moreover, research on students' learning of scientific concepts have brought to light that students use several ideas to explain scientific and everyday phenomena which are different from those learned in formal schooling. These ideas are not extinguished or replaced by scientific concepts, despite the efforts to do so in science classes. The common sense and scientific ways of understanding and talking about reality seems to be complementary in the same sense of the Bohr's complementarity (Halliday & Martin, 1993). So, we have to include in our profile of the concept of molecule not only scientific but also common sense zones. Drawing from Bachelard's notion of epistemological profile, from the history of science and from the research on children's ideas in science, we have developed the idea of a conceptual profile and used it to analyse basic scientific concepts, such as the concepts of matter and physical states of matter (Mortimer, 1995) and to investigate new ways to teach them. In the present paper, we will discuss the zones that might constitute a conceptual profile of molecule. The need of complementary views to account for the molecular structure in different contexts bring important issues for understanding and teaching chemistry, which will be discussed further in the article.

Filosofi

Samlingen med signum HF fil finns vid Humanistiska biblioteket i samband med ämnet Filosofi. Vid huvudbiblioteket finns dessutom en samling filosofisk litteratur Som grund för akademibibliotekets filosofiska samlingar ligger donationer. Några donatorer från tidigare år kan nämnas, folkskollärare Ivar Wihlman, doktor Gösta Enckell, FM Max Söderman, vicehäradshövding Jon Hartman, professor Gunnar Landtman, lektor Axel Söderholm och studerande Leo Lillja. Den filosofiska litteraturen vid Humanistiska biblioteket söks i databasen Alma med sökfunktionen Signum och söktermen HF fil.

Statskunskap och politik

Samlingen med signum HB VIc1 finns vid huvudbiblioteket och innehåller litteratur om statskunskap och politik till och med år 1999. Liknande litteratur finns i anslutning till ämnet Statskunskap. Litteratur om statskunskap och politik har ingått i bokdonationer såväl från hemlandet som från Sverige. Några donatorer av speciellt stora samlingar statsvetenskaplig litteratur kan nämnas, J.V. Brummer, J.A. Nordman, Rafael Erich, Ernst Estlander, Erik Ehrström och Tor von Wright. Politisk litteratur har donerats av Edvard Öhrnberg, Märta Björkenheim, Rafael Erich, Ernst Estlander, Hjalmar Crohn, Erik Ehrström, Carl von Bonsdorff, Jon Hartman, Allan Wallenius, Nils Källström och Hjalmar J. Procopé. Friexemplar som erhållits från och med år 1919 samt inköp har kompletterat samlingen. Litteraturen i samlingen söks med sökfunktionen Signum och söktermen HB VIc1. Litteratur tryckt före 1980 söks manuellt i den systematiska kortkatalogen. Retroaktiv inmatning i databasen Alma gör att litteratur tryckt mellan 1830 och 1979 med tiden blir sökbar i Alma. Från och med år 2000 ingår litteratur om statskunskap och politik i en numerus currens-samling.

Teologi

Samlingen teologisk litteratur med signum TF finns vid Teologiska biblioteket. Vid huvudbiblioteket finns teologisk litteratur under signum HB IIc1. Många tusen volymer teologisk litteratur har genom åren donerats till akademibiblioteket och donationer görs allt fortfarande. Bland tidigare donatorer kan som exempel nämnas prostinnan Hortense Grönstrand, häradshövding J.V. Brummer, vicehäradshövding Jon Hartman samt prostarna Konrad Ahlman, Karl Anders Troberg, Viktor Roslin, Theodor von Pfaler, Werner Wirén och C.H. Ekblom. Den teologiska litteraturen söks med sökfunktionen Signum och söktermen TF. Litteratur tryckt före 1980 söks manuellt i en kortkatalog vid Teologiska biblioteket. Retroaktiv inmatning i Alma gör att litteratur tryckt mellan 1830 och 1979 med tiden blir sökbar i Alma.

Emprego de catalisadores à base de níquel para homo- e copolimerização de estireno

This review deals with the homo- and copolymerization of styrene with nickel catalysts. The catalytic activity, polymer stereoregularity, polymer molecular weight and polydispersity are dependent upon nickel ligands and reaction parameters. Catalysts supported on silica, treated with methylaluminoxane (MAO), have shown higher stereospecificity and activity compared to homogeneous ones. The influence of these parameters is discussed focusing on the elucidation of some aspects of the polymerization mechanism.