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1.
Int J Biometeorol ; 59(12): 1849-60, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25906047

RESUMEN

The aim of this work was to analyze spatial phenology and grape quality variability related to the climatic characteristics within the Ribera del Duero Designation of Origin (DO). Twenty plots planted with cv. Tempranillo and distributed within the DO were analyzed for phenology from 2004 to 2013. Grape quality parameters at ripening (berry weight, sugar content, acidity and pH, and anthocyanins) were analyzed in 26 plots for the period 2003-2013. The relationships between phenology and grape parameters with different climatic variables were confirmed with a multivariate analysis. On average, bud break was April 27(th), bloom June 17(th), and veraison August 12th. However, phenology during the time period showed high variability, with differences between years of up to 21 days for a phenology stage. The earliest dates were observed in dry years (2005, 2006, and to a lesser degree in 2009) while the later phenology dates occurred in the wettest year of the period (2008). High correlations were found between veraison date and temperature variables as well as with precipitation-evapotranspiration recorded during the bloom-veraison period. These effects tended to be higher in the central part of the DO. Grape quality parameters also showed high variability among the dry and the wet years, and the influence of extreme temperatures on color development as well as the effect of available water on acidity were observed.


Asunto(s)
Clima , Vitis/crecimiento & desarrollo , Estaciones del Año , España , Temperatura
2.
Environ Entomol ; 39(6): 2006-16, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22182568

RESUMEN

Developmental parameters of protogyne Calepitrimerus vitis (Nalepa) (Acari: Eriophyidae) were determined at 12, 15, 17, 22, 25, 28, 31, and 34 °C to better understand seasonal activity, population growth, and ultimately more effectively manage pest mites in wine grapes. Net reproductive rate (R(o)) was greater than zero at all temperatures with the maximum R(o) (9.72) at 25 °C. The lowest estimated R(o) (0.001) occurred at 34 °C. There was a gradual decrease in mean generation time (T) as temperatures increased from 17 to 31 °C. The shortest and longest generation time was recorded at 31 °C (T = 5.5 d) and 17 °C (T = 17.5 d). Rates of natural increase were lowest at 17°C (0.035) and increased with increasing temperatures, respectively. The peak rate of natural increase value (0.141) was at 25 °C. Estimations for minimum and maximum developmental thresholds were 10.51 and 39.19 °C, respectively, while the optimum developmental temperature was 26.9 °C. The thermal constant for egg to adult development was estimated at 87.7DD. The highest fecundity was observed at 25 °C. These parameters indicated that mites begin feeding at the onset of shoot growth when tissue is most susceptible in spring. Historical weather data showed that vines are in this susceptible growth stage for longer periods in the cool Willamette Valley compared with warmer Umpqua and Applegate/Rogue Valley regions. Estimation of degree-days indicated when deutogyne mites move to overwintering refuge sites. Degree-day accumulations indicated up to 14 generations per growing season.


Asunto(s)
Interacciones Huésped-Parásitos , Ácaros/crecimiento & desarrollo , Vitis/parasitología , Animales , Femenino , Fertilidad , Masculino , Oregon , Oviparidad , Oviposición , Crecimiento Demográfico , Estaciones del Año , Temperatura
3.
Proc Natl Acad Sci U S A ; 103(30): 11217-22, 2006 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-16840557

RESUMEN

Premium wine production is limited to regions climatically conducive to growing grapes with balanced composition and varietal typicity. Three central climatic conditions are required: (i) adequate heat accumulation; (ii) low risk of severe frost damage; and (iii) the absence of extreme heat. Although wine production is possible in an extensive climatic range, the highest-quality wines require a delicate balance among these three conditions. Although historical and projected average temperature changes are known to influence global wine quality, the potential future response of wine-producing regions to spatially heterogeneous changes in extreme events is largely unknown. Here, by using a high-resolution regional climate model forced by the Intergovernmental Panel on Climate Change Special Report on Emission Scenarios A2 greenhouse gas emission scenario, we estimate that potential premium winegrape production area in the conterminous United States could decline by up to 81% by the late 21st century. While increases in heat accumulation will shift wine production to warmer climate varieties and/or lower-quality wines, and frost constraints will be reduced, increases in the frequency of extreme hot days (>35 degrees C) in the growing season are projected to eliminate winegrape production in many areas of the United States. Furthermore, grape and wine production will likely be restricted to a narrow West Coast region and the Northwest and Northeast, areas currently facing challenges related to excess moisture. Our results not only imply large changes for the premium wine industry, but also highlight the importance of incorporating fine-scale processes and extreme events in climate-change impact studies.


Asunto(s)
Agricultura/métodos , Clima , Ecología , Ambiente , Geografía , Efecto Invernadero , Calor , Temperatura , Estados Unidos , Vitis , Tiempo (Meteorología) , Vino
4.
Cell Tissue Res ; 303(3): 381-9, 2001 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11320654

RESUMEN

Primary cell cultures and organ fragments of rat thymus were characterised by use of a panel of antibodies raised against the neural adhesion molecule L1, tyrosine hydroxylase, protein gene product 9.5, nerve growth factor, calcitonin gene-related peptide, glial fibrillary acidic protein, vimentin, pan-cytokeratin, a ganglioside of neural crest and neuroendocrine cells (A2B5), and thymulin (4 beta). Immunoreactivity for neural markers only was identified in a single morphology (nerve-like) of cell in culture and throughout the adult thymus as fine, tortuous staining. Immunoreactivity for endocrine markers only was identified in polygonal epithelial-like cells in culture, throughout viable tissue in fragment culture and in the subcapsular cortex of the adult thymus. Immunoreactivity for both endocrine and neural markers was identified in three distinct morphologies in cell culture: elongate, spherical, and stellate. Similar results were observed in the mitotic periphery of the cultured fragments and in the medulla and cortico-medullary junction of the adult thymus. Cells with immunoreactivity to A2B5 were present in primary and fragment cultures and occurred throughout the adult thymus. The apparent diversity of cell immunoreactivity in primary and fragment thymic cultures suggests that numerous neural and endocrine factors may be required for the development and/or regeneration of the thymic microenvironment.


Asunto(s)
Células Epiteliales/citología , Moléculas de Adhesión de Célula Nerviosa/análisis , Cresta Neural/citología , Timo/citología , Animales , Biomarcadores/análisis , Células Cultivadas , Células Epiteliales/inmunología , Técnica del Anticuerpo Fluorescente , Inmunohistoquímica , Técnicas In Vitro , Masculino , Moléculas de Adhesión de Célula Nerviosa/inmunología , Cresta Neural/inmunología , Neuropéptidos/análisis , Neuropéptidos/inmunología , Neurotransmisores/análisis , Neurotransmisores/inmunología , Ratas , Ratas Wistar , Timo/química , Timo/inmunología
6.
Mem Cognit ; 29(8): 1185-95, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11913755

RESUMEN

We examined whether retrieval from semantic memory (Experiment 1) and autobiographical memory (Experiment 2) is exclusive, or whether people can search for two things at once. In Experiment 1, participants retrieved items as quickly as possible over 4 ruin from single categories (e.g., foods, countries) and from disjunctive categories (e.g., foods or countries). In Experiment 2, participants retrieved autobiographical episodes associated with single cue words (e.g., flower, ticket) or with disjunctive cue words (e.g., flower or ticket). In both experiments, retrieval of items from the disjunctive category did not exceed predictions based on optimal sequencing of retrieval from the corresponding two single categories. That is, exclusivity was observed to occur in retrieval from among multiple nonoverlapping categories in both semantic and autobiographical memory.


Asunto(s)
Autobiografías como Asunto , Memoria , Semántica , Adolescente , Adulto , Humanos , Distribución Aleatoria
7.
Psychol Rev ; 107(1): 213-8, 2000 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10687408

RESUMEN

A unified, quantitative model for sex, twin, parent, and grandparent influences on handedness is presented. Recent research modeling the evolutionary development of genetic mechanisms for the transmission of handedness on the basis of genotype fitness has appeared to lead to the conclusion that a handedness gene cannot be located on the sex chromosomes. It is shown in this article, however, that this conclusion is not of general validity. The sex-chromosomes hypothesis is developed further, and it is demonstrated that a wide-ranging, detailed, and parsimonious account of the distribution of handedness is obtained when left-handedness is assumed to be associated recessively, and with low penetrance, with genetic variation located on the X chromosome.


Asunto(s)
Lateralidad Funcional/genética , Modelos Genéticos , Femenino , Humanos , Masculino , Cromosomas Sexuales
8.
J Anat ; 194 ( Pt 2): 255-64, 1999 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10337958

RESUMEN

Thymic epithelial cells are an important source of cytokines and other regulatory peptides which guide thymocyte proliferation and maturation. Parathyroid hormone-related protein (PTHrP), a cytokine-like peptide, has been reported to affect the proliferation of lymphocytes in vitro. The studies presented here were undertaken to test the hypotheses that PTHrP is produced locally within the thymus where it could influence thymocyte maturation and, more specifically, that thymic epithelial cells (TEC) could be the intrathymic source of PTHrP expression. To this end, immunohistochemical studies were performed to localise PTHrP and the PTH/PTHrP receptor within the adult rat thymus. Antibodies directed against 2 different PTHrP epitopes, PTHrP(1-34) and PTHrP(34-53), demonstrated prominent specific PTHrP immunoreactivity in both subcapsular and medullary TEC. In addition, faint but specific staining for PTHrP was seen in the cortex, interdigitating between cortical lymphocytes while sparing epithelial-free subcapsular areas, thus suggesting that cortical TEC could also be a source of PTHrP immunoreactivity. In contrast, PTH/PTHrP receptor immunoreactivity was only seen in medullary and occasional septal TEC; no evidence of cortical or lymphocytic PTH/PTHrP receptor immunoreactivity was detected. Immunohistochemical studies of cultured cytokeratin-positive rat TEC confirmed the results of these in situ studies as cultured TEC were immunoreactive both for PTHrP and the PTH/PTHrP receptor. Thus these results demonstrate that PTHrP is produced by the epithelial cells of the mature rat thymus. This suggests that PTHrP, a peptide with known cytokine, growth factor and neuroendocrine actions, could exert important intrathymic effects mediated by direct interactions with TEC, or indirect effects on PTH/PTHrP receptor-negative thymocytes.


Asunto(s)
Hormona Paratiroidea/análisis , Receptores de Hormona Paratiroidea/análisis , Timo/química , Animales , Epitelio/química , Inmunohistoquímica , Proteína Relacionada con la Hormona Paratiroidea , Fragmentos de Péptidos/análisis , Proteínas/análisis , Ratas , Ratas Wistar
9.
Cortex ; 35(1): 123-8, 1999 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10213539

RESUMEN

In an earlier study, Dellatolas, Curt and Lellouch (1991) concluded that handedness is not related to season of birth. However, post-hoc exploration of their and other sets of data has shown that there is an apparent tendency for left-handedness to be more prevalent in the period March-July than in the period August-February. The present work tested this seasonal hypothesis prospectively among university students. It was found that the proportion of all left-handed participants who were born in the period March-July was indeed significantly greater than the proportion of all right-handed participants who were born in the same period. Furthermore, the pattern of seasonal influence upon handedness did not vary significantly between females and males. The relation between handedness and season of birth may be linked to seasonal variation in other factors such as the incidence of infectious agents.


Asunto(s)
Lateralidad Funcional/fisiología , Trabajo de Parto/fisiología , Estaciones del Año , Adolescente , Adulto , Femenino , Humanos , Masculino , Embarazo , Estudios Prospectivos , Factores Sexuales
10.
Neuroimmunomodulation ; 6(1-2): 6-22, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-9876230

RESUMEN

An account of research conducted on the transplantation of thymic cells and tissues in order to restore the functional activity of the thymus is reviewed, and discussed in the context of current concepts. Although most rodent work has been conducted on the transplantation of cultured fragments under the kidney capsule, human transplantation studies and models have used other sites or other species such as the severe combined immunodeficient mouse as hosts. The factors affecting the growth of thymic cells in culture is considered in detail since the methodology can strongly influence the cells favoured under culture conditions. An extension of this work to characterize both thymic fragments implanted under the kidney capsule of rats and cultured thymic cells has recently led to the appreciation that the adult thymus must contain a small number of neural crest-like cells. These cells have a high level of proliferation in the implanted fragments, expand in culture, and belong to a family of cytokeratin-positive cells exhibiting immunoreactivity for a wide range of neuropeptides and transmitters. Thus primary cultures of thymus can contain a wide range of glia-like cells. This can be explained by the fact that the thymus, in addition to having a mesenchymal neural crest component, is probably derived from cardiac neural crest. Closely associated neural crest also has glia-like properties (the supporting cells of the enteric nervous system). These finding can account for the large number of reports of epithelial cells of the adult thymus being immunoreactive to antibodies raised to neuroendocrine and neurotransmitters. Neuroimmune interactions in the thymus are more fundamental than previous work had suggested.


Asunto(s)
Regeneración , Timo/fisiología , Timo/trasplante , Animales , Técnicas de Cocultivo , Medios de Cultivo , Técnicas de Cultivo , Humanos
11.
Brain Behav Immun ; 12(3): 163-80, 1998 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-9769154

RESUMEN

In order to study the functional development of a thymus in an experimental model, small pieces of adult rat thymic tissue were cultured for 9 days and implanted under the kidney capsule of littermates. The tissues were examined with a panel of antibodies raised against thymic and neural factors and neural crest cells at intervals from 5 to 13 days. At 5 days post-implantation, there were groups of L1+ cells within the implants that reacted with antibodies raised against neural and neural crest cell markers. L1+ cells were highly mitotic, rounded cells measuring 8.7 +/- 0.6 micrometer in diameter. Double immunostaining with different combinations of antibodies showed that 94% of the L1+ cells were also TH+, and many were HNK-1/NCAM+, PGP 9.5+, NGF+, chromogranin A+, VIP+, S100+, CGRP+, GAD+, and A2B5+. A few were also pan-cytokeratin+. These results indicate that these cells are derived from neural crest derived cells and belong to the neuroepithelial line of development. The L1+ cells were most numerous before nerves appeared (about Day 9) and reduced in number and extent as the thymus differentiated. The neural crest cells occasionally had long cytoplasmic extensions, but it was not possible to decide if they formed the nerves that appeared in the implants. Adult thymuses also contained a population of L1+ and HNK-1/NCAM+ cells, mainly in the subcapsular cortex, the septa, and the medulla. These cells could be a source of neural crest cells able to repopulate the implant. The adult thymus may always contain a reservoir of cells potentially capable of producing neuropeptides and transmitter factors required for thymic growth and regeneration.


Asunto(s)
Cresta Neural/citología , Cresta Neural/inmunología , Timo/trasplante , Factores de Edad , Animales , Western Blotting , Antígenos CD57/análisis , Trasplante de Células , Células Cultivadas , Electroforesis en Gel de Poliacrilamida , Células Epiteliales/citología , Células Epiteliales/inmunología , Células Epiteliales/trasplante , Técnica del Anticuerpo Fluorescente , Riñón , Complejo de Antígeno L1 de Leucocito , Masculino , Glicoproteínas de Membrana/análisis , Moléculas de Adhesión de Célula Nerviosa/análisis , Cresta Neural/química , Neuropéptidos/análisis , Neuropéptidos/inmunología , Neurotransmisores/análisis , Neurotransmisores/inmunología , Ratas , Ratas Wistar , Timo/química , Timo/citología
12.
Mem Cognit ; 26(2): 193-200, 1998 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-9584428

RESUMEN

Memory for frequently encountered road signs was investigated. In Experiment 1, the average level of recall of road sign features was found to be only 47%. In Experiment 2, more left-handed than right-handed people recalled that a walking figure faces right on one sign, whereas more right-handed than left-handed people recalled that a digging figure faces left on another sign. Performance thus reflected not a difference in level of mnemonic ability between left-handed and right-handed groups but instead the compatibility between group and task. In Experiment 3, participants were asked to draw any figure walking and any figure digging, with a pattern of results similar to that of Experiment 2. It is suggested that handedness effects in recall are mediated by motor imagery.


Asunto(s)
Lateralidad Funcional , Generalización Psicológica , Recuerdo Mental , Reconocimiento Visual de Modelos , Adolescente , Adulto , Conducción de Automóvil/psicología , Femenino , Humanos , Imaginación , Masculino , Orientación , Desempeño Psicomotor
13.
Placenta ; 18(4): 357-64, 1997 May.
Artículo en Inglés | MEDLINE | ID: mdl-9179929

RESUMEN

An in vitro technique for the measurement of calcium uptake into the maternal-facing fetal chorionic membrane (apical trophoblast) was used to study the relationship between calcium uptake and stage of pregnancy in the sheep. The effects on calcium uptake of varying calcium concentration and temperature of the incubation medium, of adding calcium channel blockers or heavy metals (lanthanum and nickel) or calcium ionophore/agonist were also studied. The data indicate a saturable calcium uptake process, plateauing after 15 min incubation. This uptake remained constant throughout the last third of gestation until a significant fall in uptake was noted during the final week prior to parturition. This uptake was not due to extracellular cellular diffusion since there was no significant uptake of tritiated inulin over the same period in each case. Calcium uptake in this system was also shown to be a temperature dependent process which was abolished at temperatures of 0-4 degrees C. A decrease in calcium concentration to 0.12 mM in the incubation medium also caused a corresponding decrease in calcium uptake to 21 per cent of control (1.2 mM). The addition of the heavy metals lanthanum and nickel also significantly reduced calcium uptake as did the calcium channel blockers verapamil, metoprolol and diltiazem. The calcium channel ionophore A23187 increased calcium uptake into the material facing chorion. Although the interplacentomal chorion may not be representative of the whole of the placental unit, it clearly contains a specific calcium uptake process under local physiological control. The blocking of calcium uptake by the specific I-type calcium channel blocker verapamil may indicate the presence of I-type channels of unusually low sensitivity since the concentration needed to block them was much higher than would be required for excitable I-type channels in isolated cells.


Asunto(s)
Calcio/metabolismo , Corion/metabolismo , Placenta/metabolismo , Ovinos/metabolismo , Ácido 3-piridinacarboxílico, 1,4-dihidro-2,6-dimetil-5-nitro-4-(2-(trifluorometil)fenil)-, Éster Metílico/farmacología , Animales , Transporte Biológico , Calcimicina/farmacología , Agonistas de los Canales de Calcio/farmacología , Bloqueadores de los Canales de Calcio/farmacología , Femenino , Edad Gestacional , Ionóforos/farmacología , Cinética , Lantano/farmacología , Níquel/farmacología , Embarazo , Temperatura , Tapsigargina/farmacología
14.
Placenta ; 18(2-3): 211-8, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9089784

RESUMEN

The calcium requirement of the ovine fetus increases progressively throughout pregnancy. The 9-kDa calcium binding protein (calbindin-D9k; 9CBP) is considered to be a reliable marker for epithelia mediating calcium transport. This quantitative in situ hybridization study shows that the levels of 9CBP mRNA show a pregnancy stage-related increase which correlates with fetal calcium demand only in maternal endometrial gland and fetal interplacentomal trophoblast epithelia. Levels of 9CBP mRNA in the placentome, which has by far the greater area of maternofetal contact, show no changes during pregnancy. mRNA for the CaATPase enzyme, a second requirement for calcium transport, is shown to be present in epithelia in interplacentomal and placentomal regions but shows no change in concentration as pregnancy progresses. Results with the 9CBP and CaATPase mRNAs confirm our recent immunocytochemical results with ruminant placenta and indicate the basis for a cellular calcium transport system analogous to that in the enterocyte. The interplacentomal trophoblast system appears to be eminently suitable for investigations of details of the cellular mechanism and control of epithelial calcium transport.


Asunto(s)
ATPasas Transportadoras de Calcio/genética , Placenta/fisiología , ARN Mensajero/biosíntesis , Proteína G de Unión al Calcio S100/genética , Animales , Calbindinas , Femenino , Regulación del Desarrollo de la Expresión Génica , Hibridación in Situ , Placenta/metabolismo , Pruebas de Función Placentaria , Embarazo , Ovinos
15.
Br J Psychol ; 88 ( Pt 4): 609-19, 1997 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9415963

RESUMEN

A number of previous studies have demonstrated systematic misremembering of the direction in which the Queen's head faces on British coins. Two experiments were carried out to investigate whether this phenomenon is affected by a person's handedness. In both experiments, right-handed and left-handed participants were found to differ significantly in their verbal responses, with recall performance significantly worse than chance for right-handed but not for left-handed participants. Experiment 2 also examined degrees of handedness, and found significant variation in recall across the handedness range. Performance in this everyday-memory paradigm appears to be determined by both handedness and schema factors. It is proposed that although in this task the response was verbal one, relevant motor imagery may nevertheless have been activated and led to the highly unusual observation of an effect of handedness upon cognitive performance.


Asunto(s)
Lateralidad Funcional , Recuerdo Mental , Orientación , Reconocimiento Visual de Modelos , Adulto , Inglaterra , Femenino , Humanos , Masculino , Numismática , Estudiantes/psicología
16.
Cell Tissue Res ; 285(3): 477-89, 1996 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8772162

RESUMEN

In late pregnancy the sheep fetus requires 3 g of calcium per day, all of which must be transported across the trophoblast epithelium of the placenta. Such high levels of calcium transport across other epithelia are normally associated with the presence of calbindin-D9 or -28k. Our immunocytochemical results show that ovine, bovine and caprine interplacentomal trophoblast have high levels of calbindin-D9k, about eight to ten times more than in the placentomal region. The protein is detectable only in the uninucleate trophoblast cells in sheep and goat, the frequent binucleate cells show none. The calbindin-D9k is also present in the maternal glandular epithelium but not the surface epithelium of the uterus. The cellular distribution of the calbindin-D9k immunoreactivity suggests a soluble protein homogenously distributed through cytosol and nucleoplasm but absent from all organelles and intercellular spaces. In contrast, the uterine milk protein(s) are localised in Golgi cisternae and secretory vesicles in gland cells and in apical small endocytic vesicles and lysosomes in the uninucleate trophectodermal cells. The distribution of calbindin-D9k supports the concept that it mediates the high calcium flux by facilitated diffusion and not via any vesicular, membrane-bounded system.


Asunto(s)
Calcio/metabolismo , Proteínas del Tejido Nervioso/análisis , Placenta/química , Preñez/fisiología , Proteína G de Unión al Calcio S100/análisis , Animales , Especificidad de Anticuerpos , Transporte Biológico , Calbindinas , Bovinos , Femenino , Glicoproteínas/análisis , Glicoproteínas/inmunología , Cabras , Inmunohistoquímica , Mucosa Intestinal/metabolismo , Intestinos/química , Intestinos/citología , Microscopía Electrónica , Peso Molecular , Proteínas del Tejido Nervioso/inmunología , Placenta/citología , Embarazo , Proteínas Gestacionales/análisis , Proteínas Gestacionales/inmunología , Proteína G de Unión al Calcio S100/inmunología , Serpinas/análisis , Serpinas/inmunología , Ovinos , Trofoblastos/química , Trofoblastos/ultraestructura
17.
Br J Psychol ; 86 ( Pt 3): 419-35, 1995 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-7551649

RESUMEN

It is well established that human cognitive processes are subject to systematic biases associated with particular emotional states. But how do these cognitive biases arise? This question was addressed by means of a pictorial Stroop task which allowed the development of such a bias to be assessed. In each of two experiments, spider-phobic participants were significantly impaired at naming the colours of phobia-related pictures relative to those of control pictures. Investigation of the magnitude of this effect for participants of different ages allowed two contrasting hypotheses concerning the development of such biases to be compared. The integral bias hypothesis asserts that the effects of emotion on cognition reflect integral links between emotional states and cognitive mechanisms, links that are not arbitrary but instead are fixed constituents of our mental architecture. In contrast, the inferred bias hypothesis asserts that these effects arise as a consequence of the gradual establishment of associations between particular emotional states and particular patterns of cognitive behaviour. It was found that the magnitude of the observed bias remained approximately constant irrespective either of the ages of participants or of the directly estimated durations of their phobias. This fixed relation provides strong support for the integral bias explanation of the cognitive effects of an emotional disturbance. Finally, the evolutionary context in which integral links between emotion and cognition may arise is discussed.


Asunto(s)
Cognición , Emociones , Estimulación Luminosa , Adolescente , Adulto , Factores de Edad , Niño , Preescolar , Miedo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores Sexuales , Encuestas y Cuestionarios
18.
Memory ; 3(1): 97-104, 1995 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-8556537

RESUMEN

Two experiments studied memory for the appearance of a Danish 20 kroner coin. The coin bears the portrait of Queen Margrethe II in profile, facing to the right. Previous studies have examined memory for British coins, which similarly bear a right-facing portrait of Queen Elizabeth II. They have revealed the occurrence of a mnemonic illusion, in that British people tend to believe the portrait faces left. This finding has been attributed to the occurrence of a joint coin-stamp schema. British stamps bear a left-facing profile of the Queen, and it is possible that information from the stamp predominates in the formation of the schema. In the case of Denmark, however, stamps bear a full-face portrait of the Queen. Nevertheless, the present experiments showed that the Coin Head Illusion is also found in Denmark. That is, the number of participants recalling the Queen's head as facing to the right was significantly below even the chance level of 50%. Further, this result occurred both for residents of Denmark and for visitors to Denmark. These findings suggest that the bias underlying the Coin Head Illusion may be a more general one than that envisaged by the joint coin-stamp schema hypothesis.


Asunto(s)
Recuerdo Mental , Ilusiones Ópticas , Orientación , Reconocimiento Visual de Modelos , Adulto , Dinamarca , Femenino , Humanos , Masculino
19.
Memory ; 2(3): 241-54, 1994 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-7584294

RESUMEN

Are amnesic patients selectively impaired in recall relative to recognition? Experiment 1 studied a group of Korsakoff amnesics and matched the amnesic level of recognition with that of control subjects by testing control recognition of unrelated words after longer delays. It was found that under these conditions the observed levels of recall were also approximately equal. In Experiment 2, a similar result occurred when the Korsakoff amnesic level of recognition for unrelated words was matched by varying the number of presentations as well as delay before testing. In Experiment 3, a similar result occurred again with a group of amnesics of mixed aetiology and recognition levels for related words matched by varying the duration of presentation and delay before testing. In this experiment, both recognition and recall of the same items were assessed. It was found that for the amnesic group the observed level of dependency between recognition and recall was less than that for the control group. One possible interpretation of this result is that the microstructure of the recall process may be selectively disturbed in amnesia. The principal finding, however, is that in all three experiments there was no significant evidence of the existence in amnesia of a selective deficit in the overall level of recall relative to that of recognition.


Asunto(s)
Trastorno Amnésico Alcohólico/psicología , Recuerdo Mental , Adulto , Trastorno Amnésico Alcohólico/fisiopatología , Análisis de Varianza , Estudios de Casos y Controles , Humanos , Memoria/fisiología , Recuerdo Mental/fisiología , Persona de Mediana Edad , Factores de Tiempo
20.
Am J Kidney Dis ; 22(1): 44-52, 1993 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-8322792

RESUMEN

Studies to assess the relationship between plasma arginine vasopressin concentration (Pavp) and plasma osmolality (Posm) were performed on an elderly patient with dementia who developed severe hypernatremia due to inadequate water intake following a debilitating hip fracture. Serum sodium concentrations were 174 and 196 mEq/L on two consecutive hospital admissions. During the second of these admissions, sequential measurements of Pavp and Posm were obtained as hypernatremia was gradually corrected. Pavp during this period was correlated with Posm (r = 0.887, P < 0.01), but was low despite the presence of hyperosmolality and volume depletion. Pavp decreased from 0.56 microU/mL to 0.18 microU/mL as Posm decreased from 396 to 338 mOsm/kg H2O. The regression line of this relationship intercepted the abscissa at 320 mOsm/kg H2O. Hypertonic sodium chloride infusion to reassess this relationship 2 days following the correction of hypernatremia increased Pavp only to 0.67 microU/mL while increasing Posm from 297 to 316 mOsm/kg H2O. Nevertheless, Pavp and Posm were significantly correlated (r = 0.937, P < 0.001). The slope of the regression line was 0.031, and Posm at the abscissal intercept was 292 mOsm/kg H2O. A similar increase in Posm from 290 to 310 mOsm/kg H2O during hypertonic sodium chloride infusion 11 days following the correction of hypernatremia increased Pavp to 1.95 microU/mL (r = 0.786, P < 0.05). The magnitude of the increase in Pavp at this time was equivalent to that previously observed in studies of normal subjects. The slope (0.048) and abscissal intercept (280 mOsm/kg H2O) of linear regression were also consistent with observations in studies of normal subjects.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Hipernatremia/etiología , Vasopresinas/deficiencia , Anciano , Anciano de 80 o más Años , Deshidratación/complicaciones , Deshidratación/metabolismo , Humanos , Hipernatremia/metabolismo , Masculino , Análisis de Regresión , Vasopresinas/sangre , Equilibrio Hidroelectrolítico
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