Metric fixed point theory and partial impredicativity.

We show that the Priess-Crampe & Ribenboim fixed point theorem is provable in [Formula: see text]. Furthermore, we show that Caristi's fixed point theorem for both Baire and Borel functions is equivalent to the transfinite leftmost path principle, which falls strictly between [Formula: see text] and [Formula: see text]. We also exhibit several weakenings of Caristi's theorem that are equivalent to [Formula: see text] and to [Formula: see text]. This article is part of the theme issue 'Modern perspectives in Proof Theory'.

Tratamiento quirúrgico de condroides en las bolsas guturales de un equino mediante abordaje Whitehouse modificado. Reporte de caso / Standing surgical treatment of chondroids in guttural pouches of a horse through a modified Whitehouse approach. Case report

RESUMEN Una yegua de raza caballo criollo colombiano (CCC) de 34 meses de edad fue remitida al Centro de Veterinaria y Zootecnia de la Universidad CES, en la ciudad de Medellín (Colombia), para la extracción quirúrgica de condroides en ambas bolsas guturales. La paciente se intervino en estación utilizando neuroleptoanalgesia y a continuación, se empleó la técnica Whitehouse modificado en cada bolsa gutural para extraer la totalidad de los condroides. Posteriormente, se realizó tratamiento antibiótico y antinflamatorio pre y post quirúrgico con trimetoprim-sulfadiazina y flunixin meglumine vía sistémica; además, penicilina G sódica local. Luego de la intervención la paciente fue dada de alta sin complicaciones y finalmente se evidenció la resolución completa de la condición respiratoria. El reporte de este caso permitirá conocer con detalle la técnica Whitehouse modificado, así como sus retos quirúrgicos y consideraciones, ya que a la fecha en Colombia no hay otros reportes al respecto en un CCC.

ABSTRACT A 34 months old Colombian creole mare was referred to veterinary clinic of CES University, in Medellin (Colombia), for the surgical extraction of chondroids in both guttural pouch. The patient was intervened by standing surgery using neuroleptanalgesia. The modified Whitehouse technique was subsequently performed on each guttural pouch to extract all the chondroids. Antibiotic and anti-inflammatory treatment, pre and postsurgical, was systemically administered using trimethoprim/sulfadiazine and flunixin meglumine, as well as local sodium penicillin G. After the intervention, the patient was discharged without complications and its respiratory condition came to complete solution. This case report will allow knowing in detail the modified Whitehouse surgical technique along with its surgical challenges and considerations. In Colombia, to date, there are no reports of its use in CCH.

Análisis de los elementos de mercadeo social implícitos en campañas de prevención de embarazo en adolescentes / Analysis of Social Implicit Marketing Elements in Adolescent Pregnancy Prevention Campaigns / Análise dos elementos de marketing social implícitos nas campanhas de prevenção da gravidez na adolescência

Resumen Objetivo: Este artículo analiza dos campañas orientadas a prevenir el embarazo en adolescentes, con el fin de elucidar la incorporación de elementos procedentes de disciplinas como el mercadeo, y cómo estos pudieron incidir en los logros de las mismas, a la luz del modelo de "la rueda de mercadeo social". Metodología: Se revisaron informes de estudios cualitativos y cuantitativos sobre las campañas "Sexo a lo Bien" y "Parents Speak Up!", realizadas en dos contextos sociales diferentes: una en Colombia y la otra en Estados Unidos. El procedimiento de análisis fue el rastreo de elementos de mercadeo implícitos en ambas campañas, a partir de los archivos identificados sobre las mismas. Resultados: Se evidencia que la falta de coherencia entre la definición del problema, la estrategia usada y la ejecución de la misma afecta los resultados esperados en una de las campañas. La campaña "Parents Speak Up!" presenta logros importantes, porque se basó en un buen respaldo teórico, articulado con una ejecución bien definida frente a distintos públicos focalizados. La menor efectividad de resultados en la campaña "Sexo a lo Bien" se debe a la ambiciosa propuesta, así como en la falta de coherencia entre la concepción del problema que se enfrenta y la poca claridad en definición de públicos de interés y en el contenido de los mensajes. Conclusiones: Para el logro efectivo de resultados en campañas educativas sobre prevención de embarazo en adolescentes, el mercadeo social puede aportar elementos en cuanto a incorporar el proceso de planeación, ejecución y evaluación respecto del tipo de producto, el público y el contenido de los mensajes.

Abstract Objective: this article analyses two campaigns designed to prevent adolescent pregnancy. The authors aim to clarify the implementation of elements coming from other disciplines such as marketing, and the possible effects in the campaigns' results, in light of "the social marketing wheel" model. Methodology: reports of qualitative and quantitative studies on the campaigns "Sexo a lo Bien" and "Parents Speak Up!" were studied. Those campaigns were originally implemented in different contexts: one in Colombia and one in the United States. The analysis was carried out by tracking implicit marketing elements in both campaigns, from existing records about them. Results: a lack of coherence between the problems' definition, the chosen strategy and its execution was evident and affected the expected outcomes in one of the campaigns. The "Parents Speak Up!" campaign achieved important results, because it had a strong theoretical basis, articulated with a well-defined execution for different target focused audiences. The "Sexo a lo Bien" campaign had less effective results. It was too ambitious; it lacked coherence between the aimed problem, an unclear definition of target audience and the content of the messages. Conclusions: Social marketing can offer valuable elements for and educational campaign on adolescent pregnancy to achieve effective results, such as planning, execution and evaluation of the type of product, the target audience and the content of the message.

Resumo Objetivo: este artigo analisa duas campanhas encaminhadas a prevenir a gravidez na adolescência, visando esclarecer a incorporação de elementos originários de disciplinas como o marketing, e seus possíveis efeitos nos resultados das campanhas, utilizando o modelo de "a roda de marketing social". Metodologia: revisaram-se relatórios de estudos qualitativos e quantitativos sobre as campanhas "Sexo a lo Bien" e "Parents Speak Up!", realizadas em dois contextos sociais diferentes: uma foi feita na Colômbia e a outra nos Estados Unidos. A análise foi mediante rastreio de elementos de marketing implícitos nas duas campanhas, com arquivos identificados sobre elas. Resultados: a falta de coerência entre a definição do problema, a estratégia utilizada e a sua execução foi evidente, afetando os resultados esperados em uma das campanhas. A campanha "Parents Speak Up!" obteve resultados importantes, porque teve uma forte base teórica, articulada com uma execução bem definida para diferentes públicos focalizados. A campanha "Sexo a lo Bien" teve resultados menos efetivos por ser uma proposta muito ambiciosa, e por falta de coerência entre a concepção do problema objetivo, uma definição difusa de públicos de interesse e o conteúdo das mensagens. Conclusões: para conseguir resultados efetivos nas campanhas educativas sobre a prevenção da gravidez na adolescência o marketing social pode fornecer elementos relacionado com o processo de planejamento, execução e avaliação do tipo de produto, do público alvo e do conteúdo das mensagens.

Multicentre evaluation of a direct agglutination test prototype kit (DAT-LPC) for diagnosis of visceral leishmaniasis.

In this study, we assessed the sensitivity, specificity, and diagnostic accuracy of a previously developed direct agglutination test (DAT) using a freeze-dried antigen derived from Leishmania infantum promastigotes and composed in a prototype kit for visceral leishmaniasis (VL) diagnosis, named DAT-LPC. To evaluate DAT-LPC reproducibility, the kit was used to analyse 207 serum samples from VL patients and 80 serum samples from patients with other parasitic infections or healthy subjects in four laboratories from different public health institutions in Brazil. DAT-LPC showed sensitivity between 96·2 and 99·5% (P = 0·14), specificity ranging from 96·2 to 97·5% (P = 0·95), and diagnostic accuracy ranging from 96·5 to 99% (P = 0·34). The inter-laboratory reproducibility of qualitative results was classified as excellent (κ index: 0·94-0·97). The reproducibility of the end-titre results in relation to the reference laboratory, ranged from 31 to 85%. These results demonstrate an excellent performance of the DAT-LPC, and validate it for the diagnosis of VL that could replace the immunofluorescent antibody test as the routine diagnostic test in the Brazilian public health system.

Oncocercosis: de lo básico a lo clínico / Onchocerciasis: From basics to clinical / Oncocercose: do básico ao clínico

La oncocercosis es una de las enfermedades tropicales desatendidas, producida por el nemátodo filárico Onchocerca volvulus y transmitida por la picadura de la mosca negra del género Simulium. Es considerada la segunda causa mundial de ceguera prevenible y está presente en 35 naciones de tres continentes: África, América y Asia. Existen tres países declarados libres de oncocercosis: Colombia, Ecuador y México. Las principales manifestaciones clínicas son dermatológicas y oculares; sin embargo, también se han descrito alteraciones linfáticas y neurológicas. El diagnóstico se realiza por identificación de microfilarias en biopsia de piel o esclerocorneal, nodulectomía para buscar gusanos adultos o con lámpara de hendidura y observar el parásito en el ojo. Existe tratamiento farmacológico con ivermectina o quirúrgico con extracción directa de los nemátodos adultos de los oncocercomas. Los programas mundiales se basan en control vectorial y farmacoterapia. Con los conocimientos actuales y esfuerzos mundiales, la oncocercosis continúa siendo un grave problema de salud pública y causa de discapacidad. Por estas razones, se hace necesario una actualización en el tema.

Onchocerciasis is one of the neglected tropical diseases; it is produced by the filarial nematode Onchocerca volvulus and is transmitted through the bites of infected black flies of the Simulium genus. It is considered the second leading cause of preventable blindness and is present in 35 countries on three continents: Africa, America, and Asia. The following three countries have been declared free from onchocerciasis: Colombia, Ecuador, and Mexico. The main clinical manifestations are dermatological and ocular; however, lymphatic and neurological alterations have also been described. Diagnosis is made by identification of microfilariae in skin or sclerocorneal biopsy, by nodulectomy in search of adult worms, or by using a slit lamp to observe the parasite in the eye. There is pharmacological treatment through the use of ivermectin or surgical treatment by direct removal of adult nematodes from the onchocercomas. World programs are based on vector control and drug therapy. Despite current knowledge and global efforts, onchocerciasis remains a serious public health issue and an important cause of disability. Thus, an update on the topic is warranted.

A oncocercose é uma das doenças tropicais desatendidas, produzida pelo nemátodo filárico Onchocerca volvulus e transmitida pela picada da mosca negra do gênero Simulium. É considerada a segunda causa mundial de cegueira evitáveis e está presente em 35 nações de três continentes: África, América e Ásia. Existem três países declarados livres de oncocercose: Colômbia, Equador e México. As principais manifestações clínicas são dermatológicas e oculares; apesar disso, também se há descrito alterações linfáticas e neurológicas. O diagnóstico se realiza por identificação de microfilárias em biopsia da pele ou esclerocorneano, nodulectomia para buscar larva adultas ou com lâmpada de fenda e observar o parasita no olho. Existe tratamento farmacológico com ivermectina ou cirúrgico com extração direta dos nemátodos adultos dos oncocercomas. Os programas mundiais se baseiam no controle vectorial e farmacoterapia. Com os conhecimentos atuais e esforços mundiais, a oncocercose continua sendo um grave problema de saúde pública e causa de deficiência. Por estas razões, se faz necessário uma atualização no assunto.

Caracterización de una población con discapacidad visual (baja visión y ceguera) atendida en dos instituciones prestadoras de salud de Medellín / Characterization of a population with visual disabilities (low vision and blindness) attended in two health institutions from Medellín / Caracterização de uma população com incapacidade visual (baixa visão e cegueira) atendida em duas instituições prestadoras de saúde de Medellín

Objetivo: caracterizar, en los ámbitos clínico y sociodemográfico, una población de pacientes con discapacidad visual atendidos en dos instituciones de salud de la ciudad de Medellín (departamento de Antioquia/Colombia), con énfasis en la etiología del déficit visual irreversible. Metodología: estudio observacional descriptivo. Estudio macro sobre deficiencias visuales unilaterales y bilaterales en 1 742 registros de historias clínicas para identificar pacientes con baja visión o ceguera. Aplicación de un formato de investigación orientado a validar los pacientes con discapacidad visual y se seleccionaron 107 historias clínicas. Resultados: el 56.6% presenta discapacidad visual tipo baja visión y el 43.4% discapacidad visual tipo ceguera. El déficit visual responsable de la discapacidad visual fue del 39% por causas oftalmológicas, 20% por alteraciones neuro-oftalmológicas y 17% por trastornos neurológicos de cortezas visuales. Además de la agudeza visual, se encontraron otras deficiencias de la función visual: atrofia óptica, alteración electrofisiológica de la conducción visual y encefalomalacia en cortezas visuales. El 82% de los pacientes tiene al menos una comorbilidad no oftalmológica. Conclusiones: es fundamental un adecuado registro de las características biológicas, sociales, psicológicas y de las actividades de rehabilitación de los pacientes con baja visión y ceguera, para entender en forma integral no sólo la discapacidad sino el impacto que produce.

Objective: to characterize the clinical and socio-demographical characteristics of a population of patients with visual impairment attended at two health institutions in Medellín (Antioquia, Colombia), with an emphasis on the etiology of irreversible vision loss. Methodology: Observational, descriptive study of unilateral and bilateral visual impairment in 1 742 medical records to identify patients with low vision or blindness. A research form was used to validate patients with visual impairment, and 107 medical records were selected. Results: 56.6% presented low vision and 43.4% presented blindness. Vision loss was due to ophthalmic causes in 39% of cases, 20% were caused by neuro-ophthalmic alterations and 17% by neurological disorders of the visual cortex. In addition to visual acuity, other visual impairments were found, such as optic atrophy, electrophysiological alteration of the visual pathway, and encephalomalacia in visual cortices. 82% of patients had at least one nonophthalmic comorbidity. Conclusions: Adequate registration of rehabilitation activity, biological, social, and psychological characteristics of patients with low vision and blindness is essential in order to fully understand both the impairment and its impact.

Objetivo: caracterizar, nos âmbitos clínico e sócio-demográfico, uma população de pacientes com incapacidade visual atendidos em duas instituições de saúde da cidade de Medellín (departamento de Antioquia/Colômbia), com énfase na etiologia do déficit visual irreversível. Metodologia: estudo observacional descritivo. Estudo macro sobre deficiências visuais unilaterais e bilaterais em 1 742 registros de histórias clínicas para identificar pacientes com baixa visão ou cegueira. Aplicação de um formato de investigação orientado a validar os pacientes com incapacidade visual e se selecionaram 107 histórias clínicas. Resultados: 56.6% apresenta incapacidade visual tipo baixa visão e 43.4% incapacidade visual tipo cegueira. O déficit visual responsável da incapacidade visual foi de 39% por causas oftalmológicas, 20% por alterações neuro-oftalmológicas e 17% por transtornos neurológicos de córtex visual. Ademais da agudeza visual, se encontraram outras deficiências da função visual: atrofia óptica, alteração eletrofisiológica da condução visual e encefalomalácia em córtex visual. 82% dos pacientes têm pelo menos uma comorbilidade não oftalmológica. Conclusões: é fundamental um adequado registro das características biológicas, sociais, psicológicas e das atividades de reabilitação dos pacientes com baixa visão e cegueira, para entender em forma integral não só a incapacidade senão o impacto que produz.

Sedación y analeesia con bolos de xilazina y mofina en infusión continua en unna yegua criolla Colombiana sometida a ovarioectomía en estación / Sedation and analgesia with xylazine bolus and morphine in continuous infusion in a mare standing subjected to ovariectomy: case report

En el acto quirúrgico la anestesia es un proceso que siempre conlleva riesgos. Un procedimiento común en equinos es realizar cirugías en estación para disminuir el riesgo de la anestesia general. Para los procedimientos anestésicos en estación en equinos se han utilizado las combinaciones de bolos de xilazina y anestesia local; sin embargo, la analgesia irregular y la marcada ataxia son complicaciones frecuentes. En el presente caso clínico se evaluó un protocolo de bolos de xilazina 0,6 mg/kg I.V. y morfina en infusión I.V. continua a 30 µg/kg/hora, con aplicación de anestesia local para la extraccción de un tumor de células de la granulosa en una yegua. Durante el procedimiento quirúrgico se observó una buena analgesia, sedación moderada y ataxia leve, sin alteraciones cardiovasculares o respiratorias, lo que favoreció el procedimiento quirúrgico; solamente se observó un corto periodo de amotilidad intestinal el cual fue superado espontáneamente. La yegua se recuperó totalmente del procedimiento quirúrgico y presentó evidencia de estro en dos ocasiones dentro del año siguiente a la intervención. Los procedimeintos anestésico y quirúrgico empleados en esta yegua fueron apropiados y la llevaron a su normalidad reproductiva.

Anesthesia is always a procedure that leads many risks in the quirurgical act. A common procedure in horses is to make standing surgeries to decrease the general anesthesia risks. For standing anesthetic procedures in horses there have been used combinations of xilazine bolus and local anesthesia; however, irregular analgesia and marked ataxia are frequent complications. In this clinical case it was evaluate a protocol of xilazine bolus 0,6 mg/kg I.V. and a constant rate infusion of morphine 30 µg/kg/h I.V., with local anesthesia for the extraction of a granulosa cell tumor in one mare. In general, during the surgical procedure it was observed good analgesia, moderate sedation and slight ataxia, without cardiovascular or respiratory problems which favored the surgical procedure; it was observed only a short period without intestinal motility that returned to normality spontaneously. The mare recovered fully from the surgical procedure and presented evidence of estrus twice within one year after the intervention. The anesthetic and surgical procedures used in this case were appropriate and lead recovery of the normal reproductive behavior of this mare.

Estrés y factores relacionados en padres con hijos en la unidad / Stress and related factors in parents with children in neonatal intensive care unit

Objetivo: identificar el nivel de estrés y los factores relacionados, en padres con hijos en la Unidad de Cuidado Intensivo neonatal de la Clínica Universitaria Bolivariana. Metodología: estudio cuantitativo, de tipo descriptivo, transversal. Se aplicó la escala de Estrés Parental en la Unidad de Cuidado Intensivo, PSS: NICU, desarrollada y validada por Carter y Miles. En total se estudiaron a 50 padres, escogidos a conveniencia. Resultados: la edad promedio de los padres fue de 30.6 años, el 36.7 por ciento tenían escolaridad universitaria, el 42 por ciento con estrato socioeconómico nivel 3. El 62 por ciento eran empleados, el 76 por ciento de género femenino y para el 42 por ciento era su primer hijo. El principal diagnóstico del neonato fue de enfermedad respiratoria (24 por ciento). El 44 por ciento de los padres señaló que el nivel de estrés frente a lo que vio y escuchó en la unidad fue un poco estresante. El comportamiento, el aspecto y los tratamientos del bebé, fueron un poco estresantes para el 34 por ciento. El 32 por ciento de los padres señaló que era muy estresante su relación y rol de padres, valor que fue significativo estadísticamente. La comunicación con el personal de salud, para el 34 por ciento de los padres, fue poco estresante. Para el nivel de estrés general, el 28 por ciento expresó que la experiencia en general de tener a su hijo en la unidad, fue poco estresante, mientras que el 24 por ciento indicó que fue muy estresante. Conclusión: Los padres presentaron mayor estrés, cuando se desempeñan en su rol de padres, valor con significancia estadística.

Objective: To identify the level of stress and related factors in parents of children in the Neonatal Intensive Care Unit of the Clinica Universitaria Bolivariana. Methodology: study quantitative, descriptive, transversal. We applied the Parental Stress Scale in Intensive Care Unit, PSS: NICU, developed and validated by Carter and Miles. A total of 50 parents was studied, chosen for convenience. Results: The mean age of the fathers was 30.6 years; the 36.7 percent had college education, 42 percent with socioeconomic level 3. 62 percent were employed, 76 percent female and in the 42 percent was their first child. The primary diagnosis was neonatal respiratory disease (24 percent). The 44 percent of parents said that the stress level compared to what they had seen and heard in the unit was a bit stressful. The baby behavior, appearance and treatments were a bit stressful for 34 percent. The 32 percent of parents pointed that their relationship and parenting role was very stressful, value which was statistically significant. Communication with health personnel was rushed for the 34 percent of parents. For the general stress level, 28 percent expressed that the overall experience of having your child in the unit, was little stressful, while 24 percent said that it was very stressful. Conclusion: Parents showed more stress when working in their role as parents, statistically significant value.

Introduction of fibrinogen in the treatment of hemostatic disorders during orthotopic liver transplantation: implications in the use of allogenic blood.

BACKGROUND: Orthotopic liver transplantation (OLT) requires a large amount of blood-derived resources. The indications for their availability in the surgery area is based on empirical protocols. The implementation of point-of-care apparatuses gives rise to the detection of hemostatic alterations due to functional deficits of fibrinogen. METHODS: To monitor coagulation disorders and other biochemical parameters, we used thromboelastometry (ROTEM®) and a MovlLab® unit, respectively. We evaluated the stability and firmness of the clot based on fibrin (FibTem test). The measurements were performed during all of the liver transplant stages: baseline, anhepatic, and reperfusion. Fibrinogen (hemocompletan) was administered to achieve maximum clot firmness, based on patient weight and the existence of surgical bleeding. This pilot cohort of 20 transplant patients (group B) compared outcomes with the 59 patients from the previous year (group A). RESULTS: Haemocompletan was administered to 45% of the 20 patients. The ratio of red blood cell components per patient diminished from 8.4 to 3.9 (53% reduction) and, fresh frozen plasma from 5.6 to 1.9 (65% reduction). Transfusions of platelet concentrates decreased by 50% with a ratio of 1.5-0.7 per patient. Likewise, 20% of transplant patients received no transfusions of blood products compared with 3.5% in the previous period. CONCLUSION: The incorporation of fibrinogen into the treatment of hemostatic disorders in OLT leads to a reduced use of allogenic blood products. We observed reduced number of patients who received transfusions, while those who underwent transfusion did so to a lesser degree.

Prevention of epilepsy by taurine treatments in mice experimental model.

An experimental model based on kainic acid (KA) injections replicates many phenomenological features of human temporal lobe epilepsy, the most common type of epilepsy in adults. Taurine, 2-aminoethanesulfonic acid, present in high concentrations in many invertebrate and vertebrate systems, is believed to serve several important biological functions. In addition, it is believed to have a neuroprotective role against several diseases. In the present study, an experimental mouse model based on taurine pretreatment prior to KA administration has been improved to study whether taurine has a neuroprotective effect against KA-induced behavior and cell damage. Under different treatments tested, taurine's most neuroprotective effects were observed with intraperitoneal taurine injection (150 mg/kg dosage) 12 hr before KA administration. Thus, a reduction in or total absence of seizures, together with a reduction in or even disappearance of cellular and molecular KA-derived effects, was detected in mice pretreated with taurine compared with those treated only with KA. Moreover, the use of tritiated taurine revealed taurine entry into the brain, suggesting possible changes in intracellular:extracellular taurine ratios and the triggering of pathways related to neuroprotective effects.

Comment on "Spin-1 aggregation model in one dimension".

Girardi and Figueiredo have proposed a simple model of aggregation in one dimension to mimic the self assembly of amphiphiles in aqueous solution [Phys. Rev. E 62, 8344 (2000)]. We point out that interesting results can be obtained if a different set of interactions is considered, instead of their choice (the s=1 Ising model).

Brain imaging of attentional networks in normal and pathological states.

The ability to image the human brain has provided a new perspective for neuropsychologists in their efforts to understand, diagnose, and treat insults to the human brain that might occur as the result of stroke, tumor, traumatic injury, degenerative disease, or errors in development. These new findings are the major theme of this special issue. In our article, we consider brain networks that carry out the functions of attention. We outline several such networks that have been studied in normal and pathological states. These include networks for orienting to sensory stimuli, for maintaining the alert state, and for orchestrating volitional control. There is evidence that these networks have a certain degree of anatomical and functional independence, but that they also interact in many practical situations. Damage to each of these networks, irrespective of the source, produces distinctive neuropsychological deficits. We consider the links between the etiology of the injury and changes in cognition and behavior and examine the role of brain imaging in the study of rehabilitation.

Aggregation models at high packing fraction

Dense phases of micellar aggregates have strong molecular correlation at two different levels: that of the molecules forming a micelle and that between micelles, leading to a possible phase transition from a micellar fluid to a micellar crystal. The global phase diagram may also include lamellar and other dense phases, which do not have a micellar structure. We present here a generic approach to deal with these systems through a two-level density-functional description, to first describe an isolated micellar aggregate and then the dense micellar system, obtaining the free energy in a self-consistent way from the molecular interactions. Nonmicellar dense phases are included with the same density-functional approach applied at the first level. The results are shown to be very accurate for a one-dimensional model with exact solution, and the method is then applied to a three-dimensional amphiphile model that had been successfully used to describe the properties of diluted amphiphile solutions.

Executive attention and metacognitive regulation.

Metacognition refers to any knowledge or cognitive process that monitors or controls cognition. We highlight similarities between metacognitive and executive control functions, and ask how these processes might be implemented in the human brain. A review of brain imaging studies reveals a circuitry of attentional networks involved in these control processes, with its source located in midfrontal areas. These areas are active during conflict resolution, error correction, and emotional regulation. A developmental approach to the organization of the anatomy involved in executive control provides an added perspective on how these mechanisms are influenced by maturation and learning, and how they relate to metacognitive activity.

Awareness and metacognition

Kentridge and Heywood (this issue) extend the concept of metacognition to include unconscious processes. We acknowledge the possible contribution of unconscious processes, but favor a central role of awareness in metacognition. We welcome Shimamura's (this issue) extension of the concept of metacognitive regulation to include aspects of working memory, and its relation to executive attention. Copyright 2000 Academic Press.

[Economic study on asthma in Mexico]. / Un estudio económico sobre asma en México.

OBJECTIVE: The objective of this study is to establish to cost of bronchial asthma in the budget for a Clinic-Hospital with a closed population and to learn about our achievements in controlling that illness, as well as our weaknesses and areas of opportunity. Another objective is to compare our results with similar studies in other countries. METHOD: In 1998, the Clinic Nova of Monterrey had a fixed population of 28,394 persons who receive the complete range of medical services, including hospitalization and drugs from the pharmacy. The prevalence of asthma in our clinic is 2.6%, direct and indirect costs were obtained according to the Biostatistics Department, Operative Control and Emergencies. RESULTS: In 1998, the total cost of bronchial asthma was: 1,624,765.00 pesos. The direct cost of asthma was 1,582,735.00 pesos (97% of the total) and out of this, the cost of medications was 1,131,575.00 pesos (71% of the direct costs) and 42,030.00 pesos in indirect costs only represented 3% of the total. CONCLUSION: Our results indicate that the greatest cost lies in the purchase of medication for ambulatory patients. The costs for hospitalization and visits to the emergency room only represented 10% of the total and, for that reason, our most important conclusion is that the physicians at Clinica Nova are using the preventive anti-inflammatory schemes recommended at present. This has helped to reduce the most important direct cost, hospitalization.

An implicit measure of undetected change.

Several paradigms (e.g. change blindness, inattentional blindness, transsaccadic integration) indicate that observers are often very poor at reporting changes to their visual environment. Such evidence has been used to suggest that the spatio-temporal coherence needed to represent change can only occur in the presence of focused attention. However, those studies almost always rely on explicit reports. It remains a possibility that the visual system can implicitly detect change, but that in the absence of focused attention, the change does not reach awareness and consequently is not reported. To test this possibility, we used a simple change detection paradigm coupled with a speeded orientation discrimination task. Even when observers reported being unaware of a change in an item's orientation, its final orientation effectively biased their response in the orientation discrimination task. Both in aware and unaware trials, errors were most frequent when the changed item and the probe had incongruent orientations. These results demonstrate that the nature of the change can be represented in the absence of awareness.

The clinical outcome after inferior vena cava thrombosis in early infancy.

UNLABELLED: The clinical outcome after inferior vena cava thrombosis in early infancy is unknown. We report the clinical long-term follow-up of 12 patients presenting inferior vena cava thrombosis within their first months of life (gestational age: 24-41 weeks; follow-up: 7+/-3 years). Accompanying renal venous thrombosis occurred in 9, and adrenal bleeding in 4 patients. A central venous catheter was related to the thrombosis in only four patients. Heterozygous factor V Leiden mutation was found in two of the eight infants without central venous catheter. Thrombolysis was performed in seven and effective in three infants; one infant required surgical thrombectomy. In three of eight infants with ineffective or with no therapy, spontaneous recanalization occurred during follow-up. No patient died of the thrombosis. Although no long-term anticoagulatory prophylaxis was performed, none of the children with persisting occlusion (n = 5) or stenosis (n = 1) of the inferior vena cava developed symptomatic thrombo-embolic complications. However, extensive internal collaterals (n = 6), visible varicosis (n = 5), pain in the legs (n = 3) and persisting renal disease (n = 3) with arterial hypertension (n = 2) were observed during follow-up. CONCLUSION: Inferior vena cava thrombosis of early infancy frequently persists and may cause considerable long-term morbidity. New strategies for early and long-term therapy are necessary.

Brain Mechanisms of Cognitive Skills

This article examines the anatomy and circuitry of skills that, like reading, calculating, recognizing, or remembering, are common abilities of humans. While the anatomical areas active are unique to each skill there are features common to all tasks. For example, all skills produce activation of a small number of widely separated neural areas that appear necessary to perform the task. These neural areas relate to internal codes that may not be observed by any external behavior nor be reportable by the performer. There is considerable plasticity to the performance of skills. Task components can be given priority through attention, which serves to increase activation of the relevant brain areas. Attention can also cause reactivation of sensory areas driven by input, but usually only after a delay. The threshold for activation for any area may be temporarily reduced by prior activation (priming or practice). Skill components requiring attention tend to cause interference resulting in the dual tasks effects and unified focus of attention described in many cognitive studies. Practice may change the size or number of brain areas involved and alter the pathways used by the skill. By combining cognitive and anatomical analyses, a more general picture of the nature of skill emerges.

Brain mechanisms of cognitive skills.

This article examines the anatomy and circuitry of skills that, like reading, calculating, recognizing, or remembering, are common abilities of humans. While the anatomical areas active are unique to each skill there are features common to all tasks. For example, all skills produce activation of a small number of widely separated neural areas that appear necessary to perform the task. These neural areas relate to internal codes that may not be observed by any external behavior nor be reportable by the performer. There is considerable plasticity to the performance of skills. Task components can be given priority through attention, which serves to increase activation of the relevant brain areas. Attention can also cause reactivation of sensory areas driven by input, but usually only after a delay. The threshold for activation for any area may be temporarily reduced by prior activation (priming or practice). Skill components requiring attention tend to cause interference resulting in the dual tasks effects and unified focus of attention described in many cognitive studies. Practice may change the size or number of brain areas involved and alter the pathways used by the skill. By combining cognitive and anatomical analyses, a more general picture of the nature of skill emerges.