Pop Goes the Lung: Bilateral Pneumothoraces Due to Delayed Pneumatocele Rupture in Coronavirus Disease 2019 (COVID-19).

Worldwide medical and scientific communities are focusing on further understanding coronavirus disease 2019 (COVID-19) complications and its long-term impact on survivors. Pneumatocele cases are being reported more as a consequence of this virus and a cause of pneumothorax in certain patients. In this case vignette, we present a previously healthy male with COVID-19 symptoms who required hospitalization for hypoxia and who required readmission for bilateral pneumothorax from the delayed rupture of pneumatoceles. We describe this rare pathology and provide hypotheses for possible etiologies.

The development and present status of the SOP model of associative learning.

The Sometimes Opponent Processes (SOP) model in its original form was especially calculated to address how expected unconditioned stimulus (US) and conditioned stimulus (CS) are rendered less effective than their novel counterparts in Pavlovian conditioning. Its several elaborations embracing the essential notion have extended the scope of the model to integrate a much greater number of phenomena of Pavlovian conditioning. Here, we trace the development of the model and add further thoughts about its extension and refinement.

Manejo do astigmatismo residual após implante de lente intraocular / Management of residual astigmatism after intraocular lens implantation

RESUMO Relatamos um caso de astigmatismo residual, após cirurgia de catarata com implante de lente intra-ocular (LIO) tórica (Acrysof Toric, Alcon, Frot Worth TX). A refração residual (+1,25 -2,50 x 105º) e o posicionamento da LIO implantada neste olho, foram correlacionados com a aberrometria total obtida por ray tracing de pontos individuais integrada à da face anterior da córnea obtida por topografia de Plácido, para cálculo das aberrações internas (iTrace, Tracey, Technologies, Houston TX). O cálculo do eixo ideal da LIO, para minimizar a refração residual foi realizado de acordo com Berdahl & Hardten (astigmatismfix.com). A rotação da LIO foi realizada com sucesso 5 meses após a cirurgia inicial para o eixo indicado, reduzindo o erro residual para +0,25 -0,25 x 61º e promovendo reabilitação visual sem correção de 20/20.

ABSTRACT We report a case of residual astigmatism after cataract surgery with toric intraocular lens (IOL) implantation (Acrysof Toric, Alcon, Frot Worth TX). Residual refraction (+1,25 -2,50 x 105º) and IOL positioning were correlated with total ray-tracing wavefront aberrometry integrated with anterior corneal surface Placido-based topography to calculate internal aberrations (iTrace, Tracey Technologies, Houston TX). The ideal IOL axis to minimize residual refraction was calculated with Berdahl & Hardten (astigmatismfix.com). IOL rotation to the indicated axis was successfully performed 5 months after initial surgery, reducing residual error to +0,25 -0,25 x 61º, promoting visual reabilitation, with final uncorrected distance visual acuity 20/20.

A theoretical analysis of transfer of occasion setting: SOP with replaced elements.

The available data on occasion setting led Susan Brandon and Allan Wagner (Brandon and Wagner, 1998; Wagner and Brandon, 2001) to formulate what has come to be known as a replaced-elements conception (REM) of context-dependent cues within the SOP model (Wagner, 1981). In the present paper, we review the development of the theory, and show how, with a few congenial assumptions about shared cues, it can address some of the major regularities concerning when the transfer of occasion setting does or does not occur. Among the particular examples are the relatively unique transfers that have been reported to occur between separate serial discriminations and between targets that have been trained with the same versus different reinforcers.

A theoretical note in interpretation of the "redundancy effect" in associative learning.

In a recent series of papers, Pearce and colleagues (e.g., Pearce, Dopson, Haselgrove, & Esber, 2012) have demonstrated a so-called "redundancy effect" in Pavlovian conditioning, which is the finding of more conditioned responding to a redundant cue trained as part of a blocking procedure (A+AX+) than to a redundant cue trained as part of a simple discrimination procedure (BY+CY-). This phenomenon presents a serious challenge for those theories of conditioning that compute learning through a global error-term. In this paper, we use the Rescorla and Wagner (1972) model as a prototypical example to demonstrate that the redundancy effect can be accounted for by this class of theories if the experimental stimuli are assumed to share a common component. We also point to some domains in which this approach leads to novel predictions that may deserve empirical evaluation. (PsycINFO Database Record

Cue competition effects in human causal learning.

Five experiments involving human causal learning were conducted to compare the cue competition effects known as blocking and unovershadowing, in proactive and retroactive instantiations. Experiment 1 demonstrated reliable proactive blocking and unovershadowing but only retroactive unovershadowing. Experiment 2 replicated the same pattern and showed that the retroactive unovershadowing that was observed was interfered with by a secondary memory task that had no demonstrable effect on either proactive unovershadowing or blocking. Experiments 3a, 3b, and 3c demonstrated that retroactive unovershadowing was accompanied by an inflated memory effect not accompanying proactive unovershadowing. The differential pattern of proactive versus retroactive cue competition effects is discussed in relationship to amenable associative and inferential processing possibilities.

Síndrome de Proteus: relato de casos / Proteus Syndrome: case reports

INTRODUÇÃO: A síndrome de Proteus é uma doença complexa e rara, classificada nos grupo das hamartoses. Foi primeiramente descrita em dois pacientes, em 1979, por Cohen e Hayden. Existe dificuldade no diagnóstico, sendo comum a confusão com síndromes de Klippel-Trenaunay-Weber, neurofibromatose ou Stuge-Weber. Apresentamos dois casos tratados no Serviço de Cirurgia Plástica e Reparadora da Universidade Federal do Paraná. MÉTODO: Paciente masculino (caso 1), que chegou ao serviço aos 6 anos de idade, tendo como principais apresentações lipomatoses e assimetrias. A segunda paciente (caso 2) deu entrada no serviço com 20 anos de idade e diagnóstico de síndrome de Klippel-Trenaunay-Weber, que posteriormente mostrou se tratar de síndrome de Proteus. CONCLUSÃO: A hipótese etiológica mais aceita para a doença é genética. Acredita-se que exista mosaicismo somático e que a doença seja letal no estado não mosaico. Morte prematura é bastante frequente. Entretanto, a sequela mais comum é a ocorrência de tumores incomuns. O cuidado dos pacientes portadores da síndrome é um desafio devido às suas consequências médicas e psicossociais.

INTRODUCTION: Proteus syndrome is a complex and rare disorder classified as a hamartomatous disease. It was first described in two patients in 1979, by Cohen and Hayden. Proteus syndrome is difficult to diagnose, and is often confused with Klippel-Trenaunay-Weber syndrome, neurofibromatosis, or Sturge-Weber syndrome. In this study we describe two patients who were treated at the Plastic and Reconstructive Surgery Service of the Federal University of Paraná. METHOD: A 6-year-old male patient (case 1) presented to the Service with lipomatosis and asymmetry, as the primary findings. A 20-year-old (case 2) was admitted to the Service with a diagnosis of Klippel-Trenaunay-Weber syndrome, which later was shown to be Proteus syndrome. CONCLUSION: The etiological hypothesis that is most accepted for this disease is genetic. It is believed that somatic mosaicism may occur during pathogenesis, which can be lethal in the mosaic state. Premature death is common. However, the most common sequelae are the occurrence of unusual tumors. The care of patients with this syndrome is a challenge due to medical and psychosocial consequences.

Discriminative conditioning with different CS-US intervals produces temporally differentiated conditioned responses in the two eyes of the rabbit (Oryctolagus cuniculus).

The conditioned eyeblink response (CR) in rabbits is lateralized to the eye targeted by the unconditioned stimulus (US). However, a contralateral component has been reported during concurrent discriminative conditioning of the two eyes. The authors investigated CRs produced by both eyes during conditioning with 2 different interstimulus intervals (ISIs) in which a short conditioned stimulus (CS) was paired with a US to the left eye and a long CS was paired with a US to the right eye. Whether the 2 CSs were more or less similar (or identical), the short CS produced short-latency CRs in the left eye, whereas the long CS produced long-latency CRs in the right eye. The contralateral responses to a CS trained at one ISI were separable into temporal corollaries of the ipsilateral response (suggesting a bilaterality of the CR) versus those to a CS trained at another ISI (indicating generalization between the CSs). The results indicate that the neuronal substrates subserving CRs of the two eyes involve not only a dominant lateralization but also some avenue of bilaterality.

Generality of the summation effect in human causal learning.

Considerable research has examined the contrasting predictions of the elemental and configural association theories proposed by Rescorla and Wagner (1972) and Pearce (1987), respectively. One simple method to distinguish between these approaches is the summation test, in which the associative strength attributed to a novel compound of two separately trained cues is examined. Under common assumptions, the configural view predicts that the strength of the compound will approximate to the average strength of its components, whereas the elemental approach predicts that the strength of the compound will be greater than the strength of either component. Different studies have produced mixed outcomes. In studies of human causal learning, Collins and Shanks (2006) suggested that the observation of summation is encouraged by training, in which different stimuli are associated with different submaximal outcomes, and by testing, in which the alternative outcomes can be scaled. The reported experiments further pursued this reasoning. In Experiment 1, summation was more substantial when the participants were trained with outcomes identified as submaximal than when trained with simple categorical (presence/absence) outcomes. Experiments 2 and 3 demonstrated that summation can also be obtained with categorical outcomes during training, if the participants are encouraged by instruction or the character of training to rate the separately trained components with submaximal ratings. The results are interpreted in terms of apparent performance constraints in evaluations of the contrasting theoretical predictions concerning summation.

Bilateral nature of the conditioned eyeblink response in the rabbit: behavioral characteristics and potential mechanisms.

In Pavlovian eyeblink conditioning, the conditioned response (CR) is highly lateralized to the eye to which the unconditioned stimulus (US) has been directed. However, the initial conditioning of one eye can facilitate subsequent conditioning of the other eye, a phenomenon known as the intereye transfer (IET) effect. Because a conditioned emotional response (CER), as well as the eyeblink CR, is acquired during eyeblink conditioning and influences the development of the CR, the CER acquired in initial training can plausibly account for the IET effect. To evaluate this possibility, the present study utilized previously determined eyeblink conditioning procedures that effectively decouple the degree of CER and CR development to investigate the IET effect. In each of 3 experiments rabbits were initially trained with comparison procedures that differentially favored the development of the eyeblink CR or the CER, prior to a shift of the US to the alternate eye. The observed differences in the IET suggest that the effect depends largely on the specific development of eyeblink CRs rather than the CER. The neurobiological implications of this apparent bilaterality of the eyeblink CR are discussed.

Some observations and remembrances of Kenneth W. Spence.

Kenneth W. Spence was among the most influential learning theorists of the 20th century. He was not only a pioneer in the genesis of computational models but an articulate systematist and scholar regarding the place of theory in psychology. The following observations and remembrances were offered at the University of Iowa as part of a tribute to his contributions on the 100th anniversary of his birth.

Evolution of an elemental theory of Pavlovian conditioning.

Kenneth Spence (1936, 1937) formalized a quantitative, elemental approach to association theory that has had a broad and dominating influence on learning theory for many years. A set of challenges to the basic approach has spurred the subsequent evolution of elemental theory in various ways. Four of the challenges and some resulting theoretical accommodations are described in the context of Pavlovian conditioning. The evolution involves departures from important specifics of Spence's theory, but is viewed as demonstrating the utility of the basic, elemental approach that is one of his legacies.

Configural and elemental processing in associative learning: commentary on Melchers, Shanks and Lachnit.

The paper by Melchers, Shanks, and Lachnit (2007) reviews the available evidence suggesting that there is flexible processing, such that some associative learning tasks can be solved either configurally or elementally. We find the evidence provocative but limited in its demonstrated generality and silent with respect to the theoretical mechanisms that might regulate the alleged flexibility of processing. Further research is invited to determine the scope of the variation involved and how best to account for it. At present, theories, either elemental or configural, that include mechanisms to shift the weight assigned to component stimuli appear to be potential candidates for embracing the data.

[Development of a computer program to simulate the predictions of the replaced elements model of Pavlovian conditioning]. / Desarrollo de un programa computacional para simular las predicciones del modelo de elementos reemplazados (REM) de condicionamiento pavloviano.

Despite of the apparent simplicity of Pavlovian conditioning, research on its mechanisms has caused considerable debate, such as the dispute about whether the associated stimuli are coded in an "elementistic"(a compound stimuli is equivalent to the sum of its components) or a "configural" (a compound stimuli is a unique exemplar) fashion. This controversy is evident in the abundant research on the contrasting predictions of elementistic and the configural models. Recently, some mixed solutions have been proposed, which, although they have the advantages of both approaches, are difficult to evaluate due to their complexity. This paper presents a computer program to conduct simulations of a mixed model ( replaced elements model or REM). Instructions and examples are provided to use the simulator for research and educational purposes.

Mamaplastias redutoras com cicatriz vertical e em T invertido: análise de resultados / Reduction mammaplasty with vertical scarand inverted T scar: analysis of results

Introdução: dada a evolução das técnicas de mamaplastia redutora (MR) com cicatrizes reduzidas, surgem questionamentos sobre as indicações e resultados das técnicas com cicatrizes amplas, considerando a opinião das pacientes e dos cirurgiões. Objetivo: comparar a opinião de cirurgiões e pacientes sobre resultados de MR com cicatriz reduzida e em T invertido. Métodos: analisaram-se 20 pacientes submetidas à MR, divididas em dois grupos: grupo V (cicatriz vertical, n=10) e grupo T (cicatriz em T invertido, n=10), com mais de um ano de pós-operatório. As pacientes responderam formulários com perguntas sobre os resultados obtidos. Suas fotografias foram analisadas por oito cirurgiões plásticos do Serviço, em diapositivos, numa única sessão. Os resultados foram convertidos em dados numéricos e feita a análise estatística. Resultados: houve divergência da satisfação das paciente sem relação aos cirurgiões. Considerando a forma, as pacientes estavam mais satisfeitas do que os cirurgiões, em ambos os grupos, mas especialmente no grupo T (p= 0,0283). Analisando as cicatrizes, os resultados se inverteram, sendo que as pacientes estavam mais insatisfeitas do que os cirurgiões, principalmente no grupo V (p= 0,088). Confrontando os grupos V e T, não houve diferenças estatisticamente significativas, embora tenha ocorrido mais cirurgias secundárias no grupo V. Conclusões: as pacientes do grupo T estão mais satisfeitas com seus resultados de forma do que os cirurgiões, não havendo diferença estatisticamente ignificativa quando se considerou forma e cicatrizes entre os grupos.

Background: with the evolution of the short scar mammaplasty reduction (MR) technique, it emerges questions about the indication and results of the wise pattern scars technique, considering the patient and surgeon opinion. Objective: the aim is to compare the patient and surgeon opinion about the MR results using short and inverted T scars. Methods: it was analyzed 20 patients who wer underwent to MR separated in two groups: Group V (vertical scar, n=10) e Group T (T inverted scar, n=10), with follow-up more than one year. The patients answered questions about their results. Their pictures were analyzed by 8 plastic surgeons of the Department in only one session. The results were converted to numeric data and it was made the statistic analysis of the results. Results: there were divergences of patients and surgeons satisfaction. Considering the mammary shape, the patients were more satisfied than the surgeons in both groups, but mainly in the Group T (p=0,0283). Analyzing the scars, the results are inverted; the patients were more unsatisfied than the surgeons, mainly in the Group V (p=0,088). Comparing the Groups V and T, there were not statistic differences in the mammary shape or scars but occurred more secondary procedures in the Group V. Conclusions: the patients of the Group T were more satisfied about the mammary shape than the surgeons. There were not statistic differences in the mammary shape or scars among the groups.

Stimulus specificity in the habituation of the startle response in the rat.

A series of experiments evaluated whether the habituation of the startle response of the rat to tactile and auditory cues is stimulus specific. Experiment 1 showed stimulus specificity of a short-term habituation effect, whereby the startle to the second of a pair of stimuli was significantly less when the initial stimulus involved the same rather than the different modality. Experiments 2 and 3 focused on the more persistent decrement in startle that is a result of repeated stimulation, and demonstrated that such long-term habituation to the tactile and auditory stimuli contained a stimulus specific component in addition to a generalized component. The generalized habituation observed between the tactile and auditory stimuli in the three experiments may be due to an auditory accompaniment of the tactile stimulus employed. Discussion emphasized the utility of investigating habituation in a preparation with robust specificity.

Oxaliplatin: practical guidelines for administration.

Colorectal cancer (CRC) accounts for about 11% of all new cancers in the United States and kills approximately 56,000 people each year. Although the use of antineoplastic agents has demonstrated palliation of symptoms, increased survival, and improved quality of life when compared with best supportive care, improved therapies still are needed. Oxaliplatin, released in August 2002, offers an effective expansion of the CRC treatment armamentarium. Proper dosage and administration of oxaliplatin are vital to maximizing its efficacy and safety. This article reviews administration guidelines, adverse events, side effects, and key areas for patient education.

Stimulus representation in SOP: I. Theoretical rationalization and some implications.

THE SOP MODEL [INFORMATION PROCESSING IN ANIMALS: Memory Mechanisms, Erlbaum, Hillsdale, NJ, 1981, p. 5] is described in terms of its assumed stimulus representation, network characteristics, and rules for learning and performance. It is shown how several Pavlovian conditioning phenomena can be accounted on the basis of the model's presumed stimulus representation. Challenges to the SOP model prompted the adoption of a componential stimulus representation in: AESOP [Contemporary Learning Theories: Pavlovian Conditioning and the Status of Traditional Learning Theory, Erlbaum, Hillsdale, NJ, 1989, p. 149], this was a dual representation of the unconditioned stimulus (US), and C-SOP [Contemporary Learning: Theory and Application, Erlbaum, Mahwah, NJ, 2001, p. 23], this was a multi-component representation of the conditioned stimulus (CS). The assumption of a componential CS representation, where large numbers of elements can be separately learned about, necessitated a modification of the learning rule. The modified, "constrained" rule was found useful to explain timing characteristics of Pavlovian conditioned responses, as well as data offered by Rescorla [J. Exp. Psychol. Anim. Behav. Process. 26 (2000) 428; Q. J. Exp. Psychol. 54B (2001) 53; J. Exp. Psychol. Anim. Behav. Process. 28 (2002) 163] showing that stimuli trained in compound do not share the same quantitative fate.

Stimulus representation in SOP: II. An application to inhibition of delay.

The componential extension of SOP accounts for conditioned response (CR) timing in Pavlovian conditioning by assuming that learning accrues with relative independence to stimulus elements that are differentially occasioned during the duration of the conditioned stimulus (CS). SOP, using a competitive learning rule and the assumption that temporal learning emerges via resolution of what is equivalent to an "AX+BX-" discrimination, predicts a progressive increase in the latency of the CR over training, or what Pavlov refer to as "inhibition of delay." Other componential models, which use noncompetitive learning rules, do not predict inhibition of delay. Either type of model makes the prediction indicated, independently of the length of the CS-unconditioned stimulus (US) interval. We report two experiments that demonstrated inhibition of delay when rabbits were trained with relatively long, but not with short, CS-US intervals. To account for this divergence, we assumed that the SOP stimulus trace involves two kinds of elements, some with a temporally distributed pattern of activity over the duration of the CS duration, and some with a randomly distributed pattern. This stimulus representation, not only allows for inhibition of delay with long but not short CS-US intervals, but in combination with SOP's performance rule deduces CR's with "Weber variability."

Context-sensitive elemental theory.

My theories of associative learning, like those of N. J. Mackintosh and almost all learning theorists, have employed elemental representations of the stimuli involved. We must take notice when two important contributors to elemental theory, J. M. Pearce and W. K. Estes, find sufficient problems with the theory type to cause them to defect from it. I will describe some of the essential problems, concerning the substantial influence of context on learning and retrieval, characterize the different responses of Pearce and Estes, and, then, propose a variation on a recently developed elemental model that was similarly inspired. The resulting elemental theory has a close quantitative relationship to the product-rule of Estes and D. L. Medin, and may help us to rationalize how the same formal experimental design can sometimes produce results that favour the configural interpretation of Pearce and at other times the elemental interpretation of R. A. Rescorla and A. R. Wagner, as these have often been pitted against each other.