Predictive neuronal adaptation as a basis for consciousness.

Being able to correctly predict the future and to adjust own actions accordingly, offers great survival advantage. In fact, this could be the main reason for organisms to evolve their brains. The most mysterious feature of brain activity: consciousness, also seems to be related to predicting the future and detecting surprise: a mismatch between actual and predicted situation. Even at the single neuron level, predicting future activity and adapting synaptic inputs accordingly, is the best strategy to maximize metabolic energy for a neuron. Following on those ideas, here we examine if surprise minimization by single neurons could be a basis for consciousness. First, we show in simulations that as a neural network learns a task, then the surprise within neurons, defined as: difference between actual and expected activity, changes similarly as consciousness of a learned skill in humans. Moreover, implementing adaptation of neuronal activity to minimize surprise at fast time scales (tens of ms), resulted in improved network performance. This improvement is likely due to the fact that adapting activity based on the internal predictive model, allows each neuron for a more “educated” response to stimuli. Based on those results, we propose that: neuronal predictive adaptation to minimize surprise could be a basic building block of conscious processing. This is because, adapting activity toward a predicted level, allows neurons to exchange not only information about stimulus but also about its internal model predictions and thus, to build more complex predictive models. To be precise, we provide an equation to quantify consciousness as the amount of surprise minus the size of the adaptation error. Since neuronal adaptation can be studied experimentally, this allows for directly testing our hypothesis. Specifically, we postulate that any substance affecting neuronal adaptation will also affect consciousness. Interestingly, our predictive adaptation hypothesis is consistent with multiple ideas presented previously in diverse theories of consciousness, such as global workspace theory, integrated information, attention schema theory, and predictive processing framework. In summary, we present a theoretical, computational and experimental support for the hypothesis that neuronal adaptation is a possible biological mechanism of conscious processing, and we discuss how this could provide a step toward a unified theory of consciousness.

MODL-08. OPTIMIZATION OF A NOVEL LOCAL DELIVERY SYSTEM FOR THE TREATMENTS OF SUPRATENTORIAL EPENDYMOMA

Ependymomas are the third most common paediatric brain tumour, incurable in up to 40% of cases. Until recently, ependymomas were regarded as a single disease group with all patients receiving combinations of maximal surgical resection and radiotherapy. Use of chemotherapy has been limited by the resistant nature of the tumour and poor access to tumours behind the blood brain barrier (BBB). It is now known that ependymoma comprises up to nine different molecular subgroups. One subgroup is characterized by a novel fusion protein, C11orf95-RELA, which acts as a potent driver of oncogenesis resulting in a poor prognosis. Here, we present the optimization of a novel drug delivery system that uses biodegradable hydrogels to deliver drugs with potent anti-ependymoma properties into post-resection cavity of supratentorial ependymoma. Our previous high-throughput in-vivo drug screens identified candidate ependymoma therapies with poor BBB penetrance properties. Using in-vitro delivery assays, we have confirmed and monitored the release of these compounds from the hydrogel. Additionally, we have implemented this delivery system in our preclinical mouse hospital in which mice receive standard-of-care surgery and radiotherapy. The efficacy of hydrogel-based delivery of these compounds is now being tested preclinically, in combination with radiotherapy. Treatment for ependymoma patients have not changed in the last 30 years and therefore an effective chemotherapy could add a great survival benefit to in the clinic.

Comparative study of splinted and unsplinted implant-retained maxillary overdentures without palatal coverage: A literature review

<p>The palatal coverage is considered as an auxiliary element in the distribution of tensile strains on implant maxillary total prosthesis (implant overdentures) bases, either implant-supported or retained. However, complaints in some patients due to palate and phonetic impairment are constant. The palatal coverage removal would allow the improvement of these issues as well as pharyngeal control, salivary flow and hygiene. Thus, this literature review proposed to analyze the survival rates of dental implants retaining an implant maxillary overdenture without palatal coverage in edentulous maxilla. The review was conducted in Medline database, via PubMed between 2000 to 2016 period, and limited to English language publications. The search strategy took the following key-words, referencing title and / or abstract: dental implants; maxilla; maxillary; overdenture; and palatal coverage. According the data, the rehabilitation of the maxillary edentulous with four implant-supported overdentures with bar attachments and implant-retained with ball attachments has shown great survival rates of dental implants, but there are a few studies reporting the survival rate of implant overdentures. It was concluded that the prosthetic rehabilitation of total maxillary edentulous patients is viable through palateless implant overdentures when a minimum of four to six implants were used with careful planning and execution.</p><p> </p><p><strong>Keywords</strong></p><p>Dental Implants; Maxilla; Overdenture and Palatal coverage.</p>

GERMINATION AND MORPHOLOGY OF SEEDS AND SEEDLINGS OF Parkia gigantocarpa FABACEAE: MIMOSOIDEAE

Parkia gigantocarpa is a valuable timber tree, and due to its rapid growth and great survival can be used to enrich forest clearings. The aims of this study was describe main morphological characters of seeds and seedlings, and to evaluate germination and initial growth of the species at six temperatures. The seed shape varies from elliptical, oblong or ovoid with bone consistency surface, smooth, glossy black color and presence of pleurogram. Average dimensions were 21.25 mm (length), 10.43 mm (width), and 6.15 mm (thickness). The embryo type is linear axial, with fleshy cotyledons, convex planes and dominant. The germination is epigeous phanerocotyledonary with fleshy cotyledons, and occurs between the second and fifth days after sowing. The fully developed seedling stage was reached on the fifteenth day after sowing. Temperatures of 30 and 35 C provided higher germination rates in less time and with higher root biomass allocation.Keywords: Amazon; biometrics; germination temperature; fava-atanã; forest seeds. ResumoGerminação e morfologia de sementes e plântulas de Parkia gigantocarpa Fabaceae: Mimosoidae. Parkia gigantocarpa é uma árvore de interesse madeireiro, indicada para o enriquecimento de clareiras devido seu rápido crescimento. Os objetivos deste trabalho foram descrever os principais caracteres morfológicos de sementes e plântulas, e avaliar a germinação de sementes e desenvolvimento inicial da espécie em seis temperaturas. As sementes apresentam formato que varia de elíptica, ovóide ou oblonga com superfície de consistência óssea, lisa, brilhosa de coloração negra e presença de pleurograma, com dimensões médias de 21,25 mm de comprimento, 10,43 mm de largura, e 6,15 mm de espessura. O embrião é do tipo axial linear, com cotilédones crassos, plano convexos e dominantes. A germinação é epígea fanerocotiledonar com cotilédones carnosos, e ocorre entre o segundo e quinto dias após semeadura, sendo que o estágio de plântula completamente formada é alcançado no décimo quinto dia após a semeadura. As temperaturas de 30 e 35 ºC proporcionaram elevadas taxas de germinação em menor tempo e com maior alocação de biomassa radicular.Palavras-chave: Amazônia; biometria; temperatura para germinação; fava-atanã; sementes florestais.

God's People and the Remnant

The conception of the Remnant is a distinctive element in the national consciousness of Israel. It gives expression to the radical faith of that people in their national destiny. From a purely secular point of view it may be regarded as an idea of great survival value, contributing to the spiritual toughness of Israel. Such rationalisations are within limits illuminating and legitimate. When we turn to the particular Biblical witness to the Remnant we find that it divides into two main tendencies. In the optimistic message of the so-called false prophets it was an ingredient in the eschatology of weal which served to soothe the hearts and uplift the hopes of patriotic Israelites. It was a popular belief similar to that faith in the British capacity for muddling through, which at times appears in our own people. On the other hand in the preaching of the canonical prophets the popular conception of the Remnant was subjected to rough and critical treatment and received a fresh content. Our concern is to bring out this new content given to the conception by the Prophets and to determine the meaning and importance of the Remnant for the doctrine of the Church.