Recurrent Neural-Linear Posterior Sampling for Nonstationary Contextual Bandits

An agent in a nonstationary contextual bandit problem should balance between exploration and the exploitation of (periodic or structured) patterns present in its previous experiences. Handcrafting an appropriate historical context is an attractive alternative to transform a nonstationary problem into a stationary problem that can be solved efficiently. However, even a carefully designed historical context may introduce spurious relationships or lack a convenient representation of crucial information. In order to address these issues, we propose an approach that learns to represent the relevant context for a decision based solely on the raw history of interactions between the agent and the environment. This approach relies on a combination of features extracted by recurrent neural networks with a contextual linear bandit algorithm based on posterior sampling. Our experiments on a diverse selection of contextual and noncontextual nonstationary problems show that our recurrent approach consistently outperforms its feedforward counterpart, which requires handcrafted historical contexts, while being more widely applicable than conventional nonstationary bandit algorithms. Although it is very difficult to provide theoretical performance guarantees for our new approach, we also prove a novel regret bound for linear posterior sampling with measurement error that may serve as a foundation for future theoretical work

O conhecimento tradicional sobre ecologia e extração do óleo de andiroba nas reservas de desenvolvimento sustentável Mamiraua e Amanã, AM, Amazônia Brasileira.

Por trás do aparato comercial das indústrias de produtos naturais, existe o conhecimento das populações que, tradicionalmente, extraem o óleo de andiroba e encontram dificuldades de acesso ao mercado. O objetivo deste foi identificar o conhecimento tradicional sobre a andiroba e caracterizar o modo de extração dos ribeirinhos das Reservas Mamirauá e Amanã, Amazonas, Brasil. Foram realizadas 30 entrevistas, em 18 comunidades. A maioria dos entrevistados possui ensino fundamental incompleto, a renda familiar é composta pelo extrativismo e bolsas sociais. A extração do óleo de andiroba é realizada prioritariamente para o consumo, embora haja potencial para a comercialização. Os extratores visitam o andirobal uma única vez no ano para coletar as sementes. Não identificam claramente as fases fenológicas, mas, sabem quando é o ?tempo de coletar?, por exemplo. A maioria dos informantes afirma que as andirobeiras frutificam entre novembro e junho e a dispersão acontece entre dezembro e julho, sendo melhor para coletar em maio. Declaram que as sementes são todas iguais, porém dizem ter diferença na madeira: branca ou vermelha.Todos os entrevistados relataram saber extrair o óleo e que esta é uma atividade realizada principalmente pelas mulheres. As etapas são: coleta das sementes, cozimento, secagem, descascamento, preparo da massa e escorrimento do óleo. Estas informações facilitam o manejo da atividade nessas áreas, valorizam o conhecimento tradicional associado e o empoderamento feminino na exploração de óleos de sementes florestais. Podendo alavancar a organização social para a comercialização de um produto amazônico de forma sustentável, mantendo a floresta em pé

Response Surface Method to Calculate Energy Savings Associated with Thermal Comfort Improvement in Buildings

In developed countries, a large part of the building stock in 2050 will consist of currently existing buildings. Consequently, in order to achieve the objectives in terms of energy efficiency in the building sector we must consider not only new infrastructures but also the old ones. A reduction in energy consumption for climate control of between 50 and 90% can be achieved by rehabilitation and the implementation of different energy efficiency measures. Currently, these measures to reduce energy consumption and associated CO2 emissions can be modelled using computer tools. However, high precision and detail of thermal behaviour models through simulations can mean a great computational cost for companies, which results in a blockage of servers and workers. In this paper, the Response Surface Methodology (RSM) is presented as an innovative methodology for the simplification of models for calculation of the energy savings associated with thermal comfort improvement in buildings. A single-family house model, located in three different climates, is presented as a case study in order to validate the proposed methodology. Different scenarios were simulated, addressing heating and cooling temperature set points and external wall insulation represented by the transmittance (U-value). Results obtained from energy simulation using Design Builder were contrasted against those estimated from the simplified model extracted from the RSM analysis. The results revealed a deviation lower than 3% when comparing both methods. Therefore, the simplified mathematical prediction models are demonstrated to be suitable for the study of the energy performance of buildings, saving computational time, costs and associated human resources. © 2022 by the authors. Licensee MDPI, Basel, Switzerland

A novel mutation in calcium-sensing receptor gene associated to hypercalcemia and hypercalciuria.

Background: Familial Hyperparathyroidism (HPT) and Familial benign Hypocalciuric Hypercalcemia (FHH) are the most common causes of hereditary hypercalcemia. FHH has been demonstrated to be caused by inactivating mutations of calcium-sensing receptor (CaSR) gene, involved in PTH regulation as well as in renal calcium excretion.Case presentation: In two individuals, father and son, we found a novel heterozygous mutation in CaSR gene. The hypercalcemia was present only in father, which, by contrast to the classic form of FHH showed hypercalciuria (from 300 to 600 mg/24 h in different evaluations) and a Calcium/Creatinine ratio of 0.031, instead of low or normal calciuria (<0.01 typical finding in FHH). His son showed the same mutation in CaSR gene, but no clinical signs or hypercalcemia although serum ionized calcium levels were close to the upper limit of normal values (1.30 mmol/L: normal range: 1.12-1.31 mmol/L). Sequence analysis revealed a point mutation at codon 972 of CaSR gene (chromosome 3q), located within cytoplasmic domain of the CaSR, that changes Threonine with Methionine. The father was treated with Cinacalcet 90 mg/day, with a decrease of total serum calcemia from an average value of 12.2 mg/dl to 10.9 mg/dl.Conclusion: This is a case of a novel inactivating point mutation of CaSR gene that determines an atypical clinical presentation of FHH, characterized by hypercalcemia, hypercalciuria and inadequate normal PTH levels. Functional assay demonstrated that the 972 M variant influenced the maturation of the protein, in terms of the post-translational glycosylation. The impairment of the receptor activity is in keeping with the specific localization of the 972 residue in the C-terminal tail, assigned to the intracellular signalling, that on the basis of the our findings appears to be differently modulated in parathyroid gland and in kidne

In vitro and in vivo evaluation of 99mTc-polymyxin B for specific targeting of gram-bacteria

Background: Infectious diseases are one of the main causes of morbidity and mortality worldwide. Nuclear molecular imaging would be of great help to non-invasively discriminate between septic and sterile inflammation through available radiopharmaceuticals, as none is currently available for clinical practice. Here, we describe the radiolabeling procedure and in vitro and in vivo studies of99mTc-polymyxin B sulfate (PMB) as a new single photon emission imaging agent for the characterization of infections due to Gram-negative bacteria. Results: Labeling efficiency was 97 ± 2% with an average molar activity of 29.5 ± 0.6 MBq/nmol. The product was highly stable in saline and serum up to 6 h. In vitro binding assay showed significant displaceable binding to Gram-negative bacteria but not to Gram-positive controls. In mice,99mTc-HYNIC-PMB was mainly taken up by liver and kidneys. Targeting studies confirmed the specificity of99mTc-HYNIC-PMB obtained in vitro, showing significantly higher T/B ratios for Gram-negative bacteria than Gram-positive controls. Conclusions: In vitro and in vivo results suggest that99mTc-HYNIC-PMB has a potential for in vivo identification of Gram-negative bacteria in patients with infections of unknown etiology. However, further investigations are needed to deeply understand the mechanism of action and behavior of99mTc-HYNIC-PMB in other animal models and in humans

Titanium Surface Properties Influence the Biological Activity and FasL Expression of Craniofacial Stromal Cells.

Mesenchymal stromal cells (MSCs) can be easily isolated form craniofacial bones during routine dentistry procedures. Due to their embryological origin from neural crest, they represent a suitable cell population to study cell-biomaterial interaction in the craniofacial field, including osteoinductive/osteointegrative processes. The biological and immunomodulatory properties of MSCs may be influenced by chemistry and topography of implant surfaces. We investigated if and how three different titanium surfaces, machined (MCH), sandblasted with resorbable blasting medium (RBM), and Ca++-nanostructured (NCA), may affect biological activity, osseointegration, and immunomodulatory properties of craniofacial MSCs. Cell proliferation, morphology, osteogenic markers, and FasL were evaluated on MSCs isolated from the mandibular bone after seeding on these three different surfaces. No statistically significant differences in cell proliferation were observed whereas different morphologies and growth patterns were detected for each type of surface. No difference in the expression of osteogenic markers was revealed. Interestingly, FasL expression, involved in the immunomodulatory activity of stem cells, was influenced by surface properties. Particularly, immunofluorescence analysis indicated that FasL expression increased on MCH surface compared to the others confirming the suggested role of FasL in promoting osteogenic differentiation. Titanium surface treatments and topography might reflect different biological behaviours of craniofacial MSCs and influence their osseointegration/immunomodulation properties

Evaluation of Biological Response of STRO-1/c-Kit Enriched Human Dental Pulp Stem Cells to Titanium Surfaces Treated with Two Different Cleaning Systems.

Peri-implantitis-an infection caused by bacterial deposition of biofilm-is a common complication in dentistry which may lead to implant loss. Several decontamination procedures have been investigated to identify the optimal approach being capable to remove the bacterial biofilm without modifying the implant surface properties. Our study evaluated whether two different systems-Ni-Ti Brushes (Brush) and Air-Polishing with 40 \ub5m bicarbonate powder (Bic40)-might alter the physical/chemical features of two different titanium surfaces-machined (MCH) and Ca++ nanostructured (NCA)-and whether these decontamination systems may affect the biological properties of human STRO-1+/c-Kit+ dental pulp stem cells (hDPSCs) as well as the bacterial ability to produce biofilm. Cell morphology, proliferation and stemness markers were analysed in hDPSCs grown on both surfaces, before and after the decontamination treatments. Our findings highlighted that Bic40 treatment either maintained the surface characteristics of both implants and allowed hDPSCs to proliferate and preserve their stemness properties. Moreover, Bic40 treatment proved effective in removing bacterial biofilm from both titanium surfaces and consistently limited the biofilm re-growth. In conclusion, our data suggest that Bic40 treatment may operatively clean smooth and rough surfaces without altering their properties and, consequently, offer favourable conditions for reparative cells to hold their biological properties

Studies on the antimicrobial activity and brine shrimp toxicity of Zeyheria tuberculosa (Vell.) Bur. (Bignoniaceae) extracts and their main constituents

<p>Abstract</p> <p>Background</p> <p>Due to the indiscriminate use of antimicrobial drugs, the emergence of human pathogenic microorganisms resistant to major classes of antibiotics has been increased and has caused many clinical problems in the treatment of infectious diseases. Thus, the aim of this study was to evaluate for the first time the <it>in vitro </it>antimicrobial activity and brine shrimp lethality of extracts and isolated compounds from <it>Zeyheria tuberculosa </it>(Vell.) Bur., a species used in Brazilian folk medicine for treatment of cancer and skin diseases.</p> <p>Methods</p> <p>Using the disc diffusion method, bioautography assay and brine shrimp toxicity test (<it>Artemia salina </it>Leach), we studied the antimicrobial activity and lethality of extracts and isolated compounds against three microorganisms strains, including Gram-positive (<it>Staphylococcus aureus</it>) and Gram-negative (<it>Pseudomonas aeruginosa</it>) bacteria and yeasts (<it>Candida albicans</it>).</p> <p>Results</p> <p>In this study, the extracts inhibited <it>S. aureus </it>(8.0 ± 0.0 to 14.0 ± 0.0 mm) and <it>C. albicans </it>(15.3 ± 0.68 to 25.6 ± 0.4 mm) growth. In the brine shrimp test, only two of them showed toxic effects (LC₅₀29.55 to 398.05 μg/mL) and some extracts were non-toxic or showed weak lethality (LC₅₀705.02 to > 1000 μg/mL). From these extracts, four flavones [5,6,7,8-tetramethoxyflavone (1), 5,6,7-trimethoxyflavone (2), 4'-hydroxy-5,6,7,8-tetramethoxyflavone (3), and 4'-hydroxy-5,6,7-trimethoxyflavone (4)] were isolated through bioassay-guided fractionation and identified based on the 1D and 2D NMR spectral data. By bioautography assays, compounds 1 [<it>S. aureus </it>(16.0 ± 0.0 mm) and <it>C. albicans </it>(20.0 ± 0.0 mm)] and 3 [<it>S. aureus </it>(10.3 ± 0.6 mm) and <it>C. albicans </it>(19.7 ± 0.6 mm)] inhibited both microorganisms while 2 inhibited only <it>S. aureus </it>(11.7 ± 0.6 mm). Compound 4 did not restrain the growth of any tested microorganism.</p> <p>Conclusion</p> <p>Our results showed that extracts and isolated flavones from <it>Z. tuberculosa </it>may be particularly useful against two pathogenic microorganisms, <it>S. aureus </it>and <it>C. albicans</it>. These results may justify the popular use this species since some fractions tested had antimicrobial activity and others showed significant toxic effects on brine shrimps. However, in order to evaluate possible clinical application in therapy of infectious diseases, further studies about the safety and toxicity of isolated compounds are needed.</p

What Are You Looking At? Team Fight Prediction Through Player Camera

Esport is a large and still growing industry with vast audiences. Multiplayer Online Battle Arenas (MOBAs), a sub-genre of esports, possess a very complex environment, which often leads to experts missing important coverage while broadcasting live competitions. One common game event that holds significant importance for broadcasting is referred to as a team fight engagement. Professional player's own knowledge and understanding of the game may provide a solution to this problem. This paper suggests a model that predicts and detects ongoing team fights in a live scenario. This approach outlines a novel technique of deriving representations of a complex game environment by relying on player knowledge. This is done by analysing the positions of the in-game characters and their associated cameras, utilising this data to train a neural network. The proposed model is able to both assist in the production of live esport coverage as well as provide a live, expert-derived, analysis of the game without the need of relying on outside sources