46 research outputs found

    Avoiding Wireheading with Value Reinforcement Learning

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    How can we design good goals for arbitrarily intelligent agents? Reinforcement learning (RL) is a natural approach. Unfortunately, RL does not work well for generally intelligent agents, as RL agents are incentivised to shortcut the reward sensor for maximum reward -- the so-called wireheading problem. In this paper we suggest an alternative to RL called value reinforcement learning (VRL). In VRL, agents use the reward signal to learn a utility function. The VRL setup allows us to remove the incentive to wirehead by placing a constraint on the agent's actions. The constraint is defined in terms of the agent's belief distributions, and does not require an explicit specification of which actions constitute wireheading.Comment: Artificial General Intelligence (AGI) 201

    Optimizing the depth and the direction of prospective planning using information values

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    Evaluating the future consequences of actions is achievable by simulating a mental search tree into the future. Expanding deep trees, however, is computationally taxing. Therefore, machines and humans use a plan-until-habit scheme that simulates the environment up to a limited depth and then exploits habitual values as proxies for consequences that may arise in the future. Two outstanding questions in this scheme are “in which directions the search tree should be expanded?”, and “when should the expansion stop?”. Here we propose a principled solution to these questions based on a speed/accuracy tradeoff: deeper expansion in the appropriate directions leads to more accurate planning, but at the cost of slower decision-making. Our simulation results show how this algorithm expands the search tree effectively and efficiently in a grid-world environment. We further show that our algorithm can explain several behavioral patterns in animals and humans, namely the effect of time-pressure on the depth of planning, the effect of reward magnitudes on the direction of planning, and the gradual shift from goal-directed to habitual behavior over the course of training. The algorithm also provides several predictions testable in animal/human experiments

    Cruzamento natural e distância de isolamento entre genótipos de algodão na turquia

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    The purposes of this study were to determine the percentage of out-crossing, isolation distance and pollinator insect species for cotton (Gossypium hirsutum L.) seed production in the Aydin region in Turkey. The glandless and red-leaf traits in G. hirsutum were used as genetic markers. Two experiments were conducted over two years that monitored out-crossing in adjacent rows and adjacent plants and established that the percentage of out-crossing varied. The percentage of out-crossing varied between 0% and 13.3% depending on the genetic marker. In the experiment to determine isolation distance, natural crossing percentage was not observed in 2002, while this percentage was 0.8% in the first rows in 2003. In this study, cotton fields were also visited once a week during flowering periods for seven weeks in order to determine the numbers of pollinator insect species, where the only detected species was the honey bee. The numbers of pollinator insects were 2.14% (2002) and 1.30% (2003) for adjacent rows; 1.71% (2002) and 2.00% (2003) for adjacent plants in glandless parcels. It is recommended that the isolation distance between genotypes should be approximately 1 m.Os objetivos deste estudo foram determinar a percentagem de cruzamentos livres, a distância de isolamento e as espécies de insetos polinizadores na produção de sementes de algodão (Gossypium hirsutum L.) na região de Aydin, na Turquia. Foram utilizadas as características ausência de glândulas e folhas vermelhas como marcadores de G. hirsutum. Dois experimentos foram conduzidos durante dois anos, nos quais os cruzamentos livres em linhas e plantas adjacentes foram monitorados, tendo sido comprovada uma variação na percentagem de cruzamentos livres que variou entre 0 e 13,3% dependendo do marcador genético. No experimento de determinação da distância de isolamento, não se observou cruzamento natural em 2002, mas em 2003 sua percentagem foi de 0,8%, apenas nas primeiras linhas. Neste estudo, os campos de algodão foram visitados uma vez por semana, por sete semanas, para determinar o número de espécies de insetos polinizadores, tendo sido encontradas abelhas produtoras de mel. O número encontrado foi de 2,14% (2002) e 1,30% (2003) para linhas adjacentes; 1,71% (2002) e 2,00% (2003) para plantas em parcelas com ausência de glândulas. É recomendado que a distância de isolamento entre genótipos deva ser de aproximadamente 1 m

    Colistin Resistance Profiles and Genotypes of Escherichia coli Isolates from Dogs and Cats

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    Background: Nowadays, antibiotic resistance has become an important problem, posing a serious threat to both human and animal medicine. Colistin is one of the last-resort drugs for the treatment of particularly caused by multidrug resistant bacteria. The aim of this study was to investigate the resistance of Escherichia coli strains against colistin and the presence of colistin resistance genes (mcr1, mcr2 and mcr3) in them. Antibiotyping and genotyping of all strains was also aimed. Materials, Methods & Results: A total of 75 isolates of Escherichia coli from healthy animals (38 dogs and 37 cats) were screened for colistin resistance by cultivation in a screening agar and then microbroth dilution method was performed. Antibiotic susceptibilities of the isolates were determined by KBDDM. The presences of mcr1, mcr2 and mcr3 genes were investigated by PCR. The colistin resistant strains were genotyped by using RAPD-PCR, and antibiotyped based on resistance profiles. In the screening test, 1 strain in cats and 2 strains in dogs were colistin-resistant. However, 18.6% of strains (from 14 cats and 3 dogs) were found as colistin-resistant in the microdilution test. MDR status was 76.31% and 97.29% in dog and cat strains, respectively. The colistin-resistant strains showed 78-100% and 65-90% similarities with respect to their antibiotypes and genotypes, respectively. mcr1, mcr2 and mcr3 genes were not found in any of the strains. Discussion: There is an increase in infections brought on by Gram negative bacteria with various antibiotic resistances in addition to infections brought on by bacteria that are antibiotic-resistant. In order to cure illnesses caused by resistant bacteria, the repurposing of outdated antibiotics may be on the table. Colistin is a crucial antibiotic in veterinary medicine, according to a number of published perspectives, although it should only be administered with caution. However, the discovery of the plasmid-derived mcr1 gene and subsequent reports that this gene has propagated around the world. Escherichia coli strains isolated from companion animals have been found to carry the mcr1 (colistin resistance gene), and possible human-animal cross-contamination has been looked into. The findings demonstrated that mcr1-carrying E. coli might inhabit pets and spread between people and animals. The cat and dog strains used in this investigation had variable colistin resistance rates, which varied between trials. Although no isolates were found to be positive for the mcr1-3 genes in this study, it is believed that colistin resistance, which is determined phenotypically, should not be ignored in terms of spreading both in cat and dog populations as well as in terms of risk to human health, given the possibility that resistance could occur with other different mechanisms. Epidemiological research still uses in vitro antibacterial susceptibility patterns. Our antibiotyping method, which was based on an analysis of several antibiotic resistances, provided quantitative data. Commercial software was utilized to conduct the evaluation. There are no reports or publications that provide quantitative antibiotyping data for E. coli strains in the literature. A popular technique for genotyping different bacterial species is RAPD-PCR. By determining if certain specific genotypes are similar to those of other resistance strains, RAPD-PCR and other genotyping data can be compared with antibiotic resistance profiles to determine the specific risk of treatment resistance in infectious diseases. All organisms that were colistin resistant exhibited multiple antibiotic resistance, and these findings were also related to RAPD genotypes. The findings indicated that colistin-resistant E. coli bacteria could potentially represent a risk to human health and were thought to be transmitted from cats and dogs to humans and vice versa. Keywords: antibiotyping, cats, colistin resistance, dogs, Escherichia coli, genotyping

    Evaluation of cotton (Gossypium spp.) Germplasm for heat tolerance under normal and late planting time

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    The objective of this study was to determine cotton (Gossypium ssp.) germplasm for heat tolerance under normal and late planting time. For this aiming 200 cotton genotypes and five check varieties (Gloria, SG 125, Flash, Ozbek 105 and Candia) were evaluated under two different temperature regimes and experiments were conducted according to the augmented design with four blocks. Field studies were carried out at the GAP International Agricultural Research and Training Center’s experimental area in Diyarbakır, Turkey, in 2016 cotton growing season. In the study heat susceptibility index was used for discriminate to the genotypes for heat tolerance. Genotypes were classified into four groups based on the heat susceptibility index. The results of this study indicated that five cotton genotypes (TAM 139-17 ELS, CIM-240, Haridost, MNH-990 and AzGR-11835) were in highly heat tolerant, 28 genotypes were found heat tolerant, 56 genotypes were in the moderately heat tolerant and other 120 genotypes were observed susceptible for heat tolerance. Based on the heat susceptibility index, five cotton genotypes can be used as parent for heat tolerance improvement in the cotton breeding program where high temperature is a limiting factor for seed cotton yield

    Anadolu Mandalarında Q Fever Hastalığının Serolojik Olarak Araştırılması

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    Buffaloes as in other animals have been demonstrated to play a role in certain diseases transmitted to susceptible animalsand human populations. In this study, serum samples were collected from Anatolian Buffaloes in breeding Samsun and around were examinedfor Q Fever. For this purpose, 184 sera were analyzed with commercial ELISA test kit. Totally 29 (15.8%) were determined positive for Q Feverfrom examined 184 serum samples. Serum samples obtained from Anatolian Buffaloes were examined first time in terms of serologically in ourregion respect to Q Fever. As a result, the data provided within the scope of the research indicate a Q Fever seropositivity level that could pose arisk for our indigenous buffalo population. We concluded that the data obtained from this study can constitute a resource to similar studies in ourregion. The epidemiology of the disease can be elaborated in the light of studies that will be carried out with more comprehensive researches inour region.Mandaların, diğer hayvanlarda olduğu gibi bazı hastalıkların duyarlı hayvan popülasyonlarına ve insanlara bulaştırılmasında rol oynadıkları ortaya konulmuştur. Bu çalışmada, Samsun ili ve ilçelerinde yetiştiriciliği yapılan Anadolu Mandalarına ait kan serum örnekleri Q fever hastalığı yönünden incelendi. Bu amaçla, 184 kan serumu ticari bir ELISA kiti ile test edildi. İncelenen 184 serum örneğinin 29 (%15.8)’u Q fever hastalığı açısından seropozitif bulundu. Bu araştırma ile bölgemizde ilk kez Anadolu Mandalarına ait serum örnekleri Q fever yönünden serolojik olarak incelendi. Sonuç olarak, proje kapsamında sağlanan veriler bölgemiz manda populasyonu için risk oluşturabilecek düzeyde Q fever seropozitifliğine işaret etmektedir. Yürütülen araştırmadan elde edilen verilerin, yöremizde yapılacak benzer çalışmalara kaynak teşkil edebileceği kanısına varıldı. Bölgemizde daha kapsamlı projelerle gerçekleştirilecek araştırmalar ışığında hastalığın epidemiyolojisi detaylı bir şekilde ortaya konulabilecektir
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