Journal articles: 'AFLGo'

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He, Yubo, and Yuefei Zhu. "RLTG: Multi-targets directed greybox fuzzing." PLOS ONE 18, no. 4 (April 12, 2023): e0278138. http://dx.doi.org/10.1371/journal.pone.0278138.

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Directed greybox fuzzing guides fuzzers to explore specific objective code areas and has achieved good performance in some scenarios such as patch testing. However, if there are multiple objective code to explore, existing directed greybox fuzzers, such as AFLGo and Hawkeye, often neglect some targets because they use harmonic means of distance and prefers to test those targets with shorter reachable path. Besides, existing directed greybox fuzzers cannot calculate the accurate distance due to indirect calls in the program. In addition, existing directed greybox fuzzers fail to address the exploration and exploitation problem and have poor efficiency in seed scheduling. To address these problems, we propose a dynamic seed distance calculation scheme, it increase the seed distance dynamically when the reachable path encounter indirect call. Besides, the seed distance calculation can deal with the bias problem in multi-targets scenarios. With the seed distance calculation method, we propose a new seed scheduling algorithm based on the upper confidence bound algorithm to deal with the exploration and exploitation problem in drected greybox fuzzing. We implemented a prototype RLTG and evaluate it on real-world programs. Evaluation of our prototype shows that our approach outperforms a state-of-the-art directed fuzzer AFLGo. On the multi-targets benchmark Magma, RLTG reproduces bugs with 6.9x speedup and finds 66.7% more bugs than AFLGo.

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He, Ziheng, Peng Jia, Yong Fang, Yuying Liu, and Hairu Luo. "SwitchFuzz: Switch Short-Term Goals in Directed Grey-Box Fuzzing." Applied Sciences 12, no. 21 (November 2, 2022): 11097. http://dx.doi.org/10.3390/app122111097.

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In recent years, fuzzing has become a powerful tool for security researchers to uncover security vulnerabilities. It is used to discover software vulnerabilities by continuously generating malformed inputs to trigger bugs. Directed grey-box fuzzing has also been widely used in the verification of patch testing and in vulnerability reproduction. For directed grey-box fuzzing, the core problem is to make test cases reach the target and trigger vulnerabilities faster. Selecting seeds that are closer to the target site to be mutated first is an effective method. For this purpose, the DGF calculates the distance between the execution path and the target site by a specific algorithm. However, as time elapses in the execution process, the seeds covering a larger amount of basic blocks may be overlooked due to their long distances. At the same time, directed fuzzing often ignores the impact of coverage on test efficiency, resulting in a local optimum problem without accumulating enough valuable test cases. In this paper, we analyze and discuss these problems and propose SwitchFuzz, a fuzzer that can switch short-term goals during execution. SwitchFuzz keeps shortening the distance of test cases to reach the target point when it performs well and prioritizes reaching the target point. When positive feedback is not achieved over a period of time, SwitchFuzz tries to explore more possibilities. We compared the efficiency of SwitchFuzz with that of AFLGO in setting single target and multiple targets for crash recurrence in our experiments, respectively. The results show that SwitchFuzz produces a significant improvement over AFLGO in both the speed and the probability of triggering a specified crash. SwitchFuzz can discover more edges than AFLGO in the same amount of time and can generate seeds with smaller distances.

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Chen, Chen, Han Xu, and Baojiang Cui. "PSOFuzzer: A Target-Oriented Software Vulnerability Detection Technology Based on Particle Swarm Optimization." Applied Sciences 11, no. 3 (January 25, 2021): 1095. http://dx.doi.org/10.3390/app11031095.

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Coverage-oriented and target-oriented fuzzing are widely used in vulnerability detection. Compared with coverage-oriented fuzzing, target-oriented fuzzing concentrates more computing resources on suspected vulnerable points to improve the testing efficiency. However, the sample generation algorithm used in target-oriented vulnerability detection technology has some problems, such as weak guidance, weak sample penetration, and difficult sample generation. This paper proposes a new target-oriented fuzzer, PSOFuzzer, that uses particle swarm optimization to generate samples. PSOFuzzer can quickly learn high-quality features in historical samples and implant them into new samples that can be led to execute the suspected vulnerable point. The experimental results show that PSOFuzzer can generate more samples in the test process to reach the target point and can trigger vulnerabilities with 79% and 423% higher probability than AFLGo and Sidewinder, respectively, on tested software programs.

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Feng, Tao, and Jinkun Liu. "Optimization Research of Directed Fuzzing Based on AFL." Electronics 11, no. 24 (December 7, 2022): 4066. http://dx.doi.org/10.3390/electronics11244066.

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Fuzz testing is the process of testing programs by continually producing unique inputs in order to detect and identify security flaws. It is often used in vulnerability mining. The most prevalent fuzzing approach is grey-box fuzzing, which combines lightweight code instrumentation with data-feedback-driven generation of fresh program input seeds. AFL (American Fuzzy Lop) is an outstanding grey-box fuzzing tool that is well known for its quick fork server execution, dependable genetic algorithm, and numerous mutation techniques. AFLGO proposes and executes power scheduling based on a simulated annealing process for a more appropriate energy allocation to seeds, however it is neither reliable nor successful. To tackle this issue, we offer an energy-dynamic scheduling strategy based on the algorithm of the fruit fly. Adjusting the energy of the seeds dynamically controls the production of test cases. The findings demonstrate that the approach suggested in this research can test the target region more rapidly and thoroughly and has a high application value for patch testing and vulnerability replication.

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Ye, Jiaxi, Ruilin Li, and Bin Zhang. "RDFuzz: Accelerating Directed Fuzzing with Intertwined Schedule and Optimized Mutation." Mathematical Problems in Engineering 2020 (March 17, 2020): 1–12. http://dx.doi.org/10.1155/2020/7698916.

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Directed fuzzing is a practical technique, which concentrates its testing energy on the process toward the target code areas, while costing little on other unconcerned components. It is a promising way to make better use of available resources, especially in testing large-scale programs. However, by observing the state-of-the-art-directed fuzzing engine (AFLGo), we argue that there are two universal limitations, the balance problem between the exploration and the exploitation and the blindness in mutation toward the target code areas. In this paper, we present a new prototype RDFuzz to address these two limitations. In RDFuzz, we first introduce the frequency-guided strategy in the exploration and improve its accuracy by adopting the branch-level instead of the path-level frequency. Then, we introduce the input-distance-based evaluation strategy in the exploitation stage and present an optimized mutation to distinguish and protect the distance sensitive input content. Moreover, an intertwined testing schedule is leveraged to perform the exploration and exploitation in turn. We test RDFuzz on 7 benchmarks, and the experimental results demonstrate that RDFuzz is skilled at driving the program toward the target code areas, and it is not easily stuck by the balance problem of the exploration and the exploitation.

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Lin, Mingmin, Yingpei Zeng, and Yang Li. "RegFuzz: A Linear Regression-Based Approach for Seed Scheduling in Directed Fuzzing." Electronics 12, no. 17 (August 29, 2023): 3650. http://dx.doi.org/10.3390/electronics12173650.

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Directed fuzzing aims to focus on fuzzing specific locations within a target program to enhance the efficiency of vulnerability discovery. However, directed fuzzing may yield fewer vulnerabilities and obtain lower code coverage when the specified locations have little to no vulnerabilities. Additionally, the existing directed fuzzing approaches often overlook the differences in variable values when calculating distances between seeds and specific locations. In order to address these issues, this paper introduces RegFuzz, a method that improves seed scheduling in directed fuzzing. RegFuzz utilizes a linear regression model to predict the effectiveness of a seed and allocates more fuzzing opportunities to efficient seeds. Specifically, first, RegFuzz defines several labels with the corresponding trainable weights for each seed. These labels encompass seed coverage, crash efficiency, seed distance, and more. In the calculation of seed distance, RegFuzz takes into account not only the basic block distance but also the variable distance contained within those basic blocks. Second, the linear regression model continually optimizes the label weights during fuzzing, and these optimized weights are employed to predict the effectiveness of seeds. In comparison with AFLGo, AFL, and AFL++, RegFuzz demonstrates higher code coverage and a more efficient bug-finding capability across seven real-world open-source programs.

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Rustamov, Fayozbek, Juhwan Kim, Jihyeon Yu, Hyunwook Kim, and Joobeom Yun. "BugMiner: Mining the Hard-to-Reach Software Vulnerabilities through the Target-Oriented Hybrid Fuzzer." Electronics 10, no. 1 (December 31, 2020): 62. http://dx.doi.org/10.3390/electronics10010062.

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Greybox Fuzzing is the most reliable and essentially powerful technique for automated software testing. Notwithstanding, a majority of greybox fuzzers are not effective in directed fuzzing, for example, towards complicated patches, as well as towards suspicious and critical sites. To overcome these limitations of greybox fuzzers, Directed Greybox Fuzzing (DGF) approaches were recently proposed. Current DGFs are powerful and efficient approaches that can compete with Coverage-Based Fuzzers. Nevertheless, DGFs neglect to accomplish stability between usefulness and proficiency, and random mutations make it hard to handle complex paths. To alleviate this problem, we propose an innovative methodology, a target-oriented hybrid fuzzing tool that utilizes a fuzzer and dynamic symbolic execution (also referred to as a concolic execution) engine. Our proposed method aims to generate inputs that can quickly reach the target sites in each sequence and trigger potential hard-to-reach vulnerabilities in the program binary. Specifically, to dive deep into the target binary, we designed a proposed technique named BugMiner, and to demonstrate the capability of our implementation, we evaluated it comprehensively on bug hunting and crash reproduction. Evaluation results showed that our proposed implementation could not only trigger hard-to-reach bugs 3.1, 4.3, 2.9, 2.0, 1.8, and 1.9 times faster than Hawkeye, AFLGo, AFL, AFLFast, QSYM, and ParmeSan respectively but also scale to several real-world programs.

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Hsieh, Ying-Jiun, Hung-Wei Cheng, Hung-Yu Chen, and Ming-Wei Lee. "A Four-Step Cascade Drug-Release Management Strategy for Transcatheter Arterial Chemoembolization (TACE) Therapeutic Applications." Polymers 13, no. 21 (October 27, 2021): 3701. http://dx.doi.org/10.3390/polym13213701.

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The purpose of this study was to develop a four-step cascade drug-release system for transcatheter arterial chemoembolization (TACE) therapeutic applications according to disease-driven and patient-focused design theories. The four steps underlying these strategies involve the blockage of nutrient supply, nanoparticles, codelivery and the cell cytotoxic effect. Calibrated spherical gellan gum (GG) and nanoparticle-containing gellan gum microspheres were prepared using a water-in-oil emulsification method. Self-assembled nanoparticles featuring amine-functionalized graphene oxide (AFGO) as the doxorubicin (Dox) carrier were prepared. The results confirm that, as a drug carrier, AFGO–Dox nanoparticles can facilitate the transport of doxorubicin into HepG2 liver cancer cells. Subsequently, AFGO–Dox was introduced into gellan gum (GG) microspheres, thus forming GG/AFGO–Dox microspheres with a mean size of 200–700 μm. After a drug release experiment lasting 28 days, the amount of doxorubicin released from 674 and 226 μm GG/AFGO–Dox microspheres was 2.31 and 1.18 μg/mg, respectively. GG/AFGO–Dox microspheres were applied in a rabbit ear embolization model, where ischemic necrosis was visible on the ear after 12 days. Our aim for the future is to provide better embolization agents for transcatheter arterial chemoembolization (TACE) using this device.

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Bewiadzi Akakpo, Samuel. "Informal Trade Routes and Security along the Aflao-Lomé Border Region (Ghana-Togo)." Journal of Borderlands Studies 37, no. 2 (December 20, 2021): 317–37. http://dx.doi.org/10.1080/08865655.2021.2013294.

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Singh, Arti, Hana Ross, Fiona Dobbie, Allen Gallagher, Tarja Kinnunen, Divine Darlington Logo, Olivia A. Boateng, Anna Gilmore, Linda Bauld, and Ellis Owusu-Dabo. "Extent of illicit cigarette market from single stick sales in Ghana: findings from a cross-sectional survey." BMJ Open 13, no. 3 (March 2023): e062476. http://dx.doi.org/10.1136/bmjopen-2022-062476.

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ObjectiveThis study aims to measure the extent of illicit cigarette consumption from single stick sales, to determine the nature and types of illicit cigarettes present in Ghana, and to identify the factors associated with illicit cigarette consumption in Ghana.DesignA cross-sectional study using empty cigarette packs generated by 1 day’s single stick cigarette sales collected from cigarette vendors.SettingFive large cities (Accra, Kumasi, Takoradi, Tamale and Bolgatanga) and three border towns (Aflao, Paga/Hamele and Elubo) in the northern, middle and coastal belt of Ghana.Procedure and participantsTen areas were randomly selected in each city/town, and all shops selling cigarettes within 1 km of the central point were surveyed.Outcome measures(1) Estimates of the share of illicit cigarette packs in the total cigarette sales from vendors selling single stick cigarettes in Ghana; (2) nature and types of illicit cigarette packs; (3) factors associated with illicit cigarette sales in Ghana.ResultsOf a total of 4461 packs, about 20% (95% CI 18.3 to 20.7) were found to be illicit. Aflao (Ghana-Togo border) and Tamale (Ghana-Burkina Faso border) had the highest percentage of illicit cigarette sales at 99% and 46%, respectively (p<0.001). Over half of the illicit packs originated from Togo (51%), followed by Nigeria (15%) and then Cote d’Ivoire (10%). Adjusted and unadjusted logistic regression models indicated that convenience stores, border towns, pack price and the northern zone had higher odds of illicit cigarette sales.ConclusionTo effectively tackle illicit cigarettes, market surveillance and strengthening supply chain control are required, particularly at the border towns and the northern region of the country.

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Mirkhan, Sawan M., and Taha J. Omar. "Screening of Aflatoxin Production by Aspergillus flavus Isolates from Petroleum-contaminated Soil." ARO-THE SCIENTIFIC JOURNAL OF KOYA UNIVERSITY 11, no. 2 (August 25, 2023): 25–30. http://dx.doi.org/10.14500/aro.11144.

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Fungi are eukaryotic, heterogeneous, unicellular to filamentous, spore-bearing, and chemoorganotrophic organisms which lack chlorophyll. This present study was carried out to isolate and identify fungi from petroleum-contaminated soil. Several fungal genera which included Rhizopus spp., Mucor spp., Penicillium spp., Rhizoctonia spp., Aspergillus spp., Alternaria spp., and Cladosporiumspp. were isolated using potatoes dextrose agar, Czapek-Dox Agar, and Aspergillus flavus Differentiation Agar culture media that comparable with co-amoxiclav (1g) and chloramphenicol to prevent the growth of any bacteria. The direct plate and serial dilution agar plate methods were used for the isolation of fungi. Based on results, Aspergillusand Mucor spp. were the most predominant genera and had the highest number of colonies in the soil samples. In this investigation, seven out of 27 soil samples were morphologically (macroscopically and microscopically) identified, such as A. flavus. Aflatoxigenicity of A. flavus was detected using characteristics in Aspergillus differentiation agar and colony fluorescence on exposure to ultraviolet light. Moreover, molecular approaches were used for the detection of aflatoxigenic of the A. flavus isolates. Three structural (aflD, aflO, and aflP) and one regulatory (aflR) gene of the aflatoxin gene cluster of A. flavus were targeted for amplification by the polymerase chain reaction method. The aflatoxigenic of all six A. flavus isolates was detected molecularly which contained two structural (aflD, aflP)genes out of three structural genes, while there was no specific amplification of the aflO gene in the fourth, fifth, and sixth A. flavus which issimilar to the aflR gene in the first and second A. flavus.

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Anthony, Richard G., Pat E. James, and Brian R. Jordan. "Cloning and sequence analysis of aflo/lfy homologue isolated from cauliflower (Brassica oleracea L. var.botrytis)." Plant Molecular Biology 22, no. 6 (September 1993): 1163–66. http://dx.doi.org/10.1007/bf00028986.

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Santos, Mariana Teles, and Elizabeth do Nascimento. "Inteligência e personalidade: um estudo correlacional em uma amostra de universitários." Estudos de Psicologia (Campinas) 29, no. 2 (June 2012): 163–71. http://dx.doi.org/10.1590/s0103-166x2012000200002.

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O presente estudo teve como objetivo investigar a associação entre inteligência e personalidade, sendo a primeira avaliada por meio dos testes G36, Matrizes Progressivas de Raven e Bateria de Provas de Raciocínio; e a segunda, mensurada por meio do Inventário Fatorial de Personalidade. Tais instrumentos foram aplicados em uma amostra composta por 266 estudantes universitários, 77,8% dos quais do sexo feminino, com idade entre 18 e 59 anos (M=21,2). A análise das correlações de Pearson apresentou valores de correlação que variaram de 0,13 a 0,22. Os fatores desempenho, agressão e exibição correlacionaram-se positivamente com a inteligência geral medida (teste G36) e com o raciocínio mecânico e o abstrato. Já os fatores intracepção, afago, deferência, denegação e ordem correlacionaram-se negativamente com o raciocínio espacial, o mecânico e o abstrato. O estudo apontou uma associação de magnitude fraca, porém significativa, entre a inteligência e a personalidade na fase adulta.

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Nakano, Tatiana de Cássia. "Personalidade: estudo comparativo entre dois instrumentos de avaliação." Estudos de Psicologia (Campinas) 31, no. 3 (September 2014): 347–57. http://dx.doi.org/10.1590/0103-166x2014000300003.

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Com o objetivo de verificar convergências entre dois modelos de avaliação da personalidade, a Escala Fatorial de Socialização e o Inventário Fatorial de Personalidade foram aplicados em 71 participantes (43 femininos/28 masculinos) com idades entre 18 e 31 anos (M = 21,11 anos, DP = 4,28), escolaridade correspondente ao Ensino Médio (n = 28) e Ensino Superior (n = 43). Os resultados demonstraram que o fator 1 da Escala Fatorial de Socialização, Amabilidade, correlacionou-se significativamente e de forma positiva com oito necessidades avaliadas pelo Inventário Fatorial de Personalidade (Assistência, Intracepção, Afago, Deferência, Afiliação, Ordem, Persistência e Mudança). Os demais fatores (Pró-Sociabilidade e Confiança) não se relacionaram significativamente com nenhuma das necessidades avaliadas pelo Inventário Fatorial de Personalidade. Diferenças significativas devido ao sexo foram encontradas em relação às necessidades de intracepção, deferência e autonomia no Inventário Fatorial de Personalidade e amabilidade na Escala Fatorial de Socialização, e nenhuma diferença foi encontrada em relação à idade. Estudos que avaliem os demais fatores do Modelo dos Cinco Grandes Fatores de Personalidade são recomendados, assim como maior amplitude etária da amostra.

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Tai, Bowen, Jinghua Chang, Yang Liu, and Fuguo Xing. "Recent progress of the effect of environmental factors on Aspergillus flavus growth and aflatoxins production on foods." Food Quality and Safety 4, no. 1 (February 28, 2020): 21–28. http://dx.doi.org/10.1093/fqsafe/fyz040.

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Abstract The contamination of Aspergillus flavus and subsequent aflatoxins (AFs) has been considered as one of the most serious food safety problems due to their acute and chronic adverse effects on humans and animals. This review collects the available information from recent years on the effect of the major environmental factors such as water activity (aw), temperature, CO2, and pH on the fungal growth, the expression of AFs-related genes, and AFs production by A. flavus on foods. In particular, the relationship between the relative expression of key regulatory (aflR and aflS) and structural genes (aflD, aflO, aflQ, etc.) and AFs production under different environmental conditions are collected and discussed. The information collected in this review can be used to design control strategies of A. flavus and AFs contamination in practical applications, primarily during storage and processing. These data suggest that integrating various post-harvest methods with synergistic functions may be more efficient for the control of A. flavus growth and AFs production, although the individual environmental factors alone have an impact.

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Keller, Birgit, Ana Maria Braga, and Ricardo Weigert Coelho. "Relação entre a personalidade e lesões musculares em atletas de tênis de campo." Revista Brasileira de Medicina do Esporte 19, no. 2 (April 2013): 120–22. http://dx.doi.org/10.1590/s1517-86922013000200010.

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INTRODUÇÃO: A personalidade de um indivíduo é o resultado de uma complexa rede de influências de diversos fatores independentes como a constituição biológica e psicológica, além das influências do meio social, ambiental e cultural em que vive. Ela é a integração dessas partes que interagindo formam o todo. OBJETIVO: Verificar se existe relação causa-efeito entre traços de personalidade, sexo e lesão no esporte. MÉTODO: A amostra foi composta por 60 atletas com idade média de 15,6 (DP =1,5) anos, sendo 35 atletas do sexo masculino e 25 atletas do sexo feminino pertencentes à Categoria Infanto-Juvenil, participantes de torneios de tênis de campo da Federação Paranaense e Catarinense. Para a coleta de dados foi utilizado o Inventário Fatorial de Personalidade - IFP. Para tratamento dos dados utilizou-se uma MANOVA e uma ANOVA a um nível de p < 0,05. RESULTADOS: Apresentaram significância para a variável lesão com Agressão (p = 0,01) e Heterossexualidade (p = 0,00). Para a variável sexo, houve diferença significativa com Intracepção (p = 0,02); Afago (p = 0,02); Dominância (p = 0,004); Autonomia (p = 0,03); Heterossexualidade (p = 0,00). CONCLUSÃO: A agressividade é um importante traço de personalidade a ser considerado para ser controlada para prevenir e diminuir as incidências de lesões em atletas de tênis.

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Puplampu, Dzifa Adimle, Khiddir Iddris, Victor Alorbu, Jonathan Otumfuor Asante, Judges Laar Takaman, and Alex Barimah Owusu. "Shoreline Change Analysis of the Eastern Coast of Ghana between 1991 and 2020." Journal of Environmental Geography 16, no. 1-4 (April 5, 2023): 11–21. http://dx.doi.org/10.14232/jengeo-2023-44339.

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The Eastern Coastline of Ghana is facing intense natural and anthropogenic disturbances, which pose a serious threat to the coastal community, ecosystem, and livelihoods. This study assessed the shoreline changes occurring along the Eastern Coast of Ghana stretching 149 km from Laloi Lagoon West of Prampram to Aflao, Ghana. The study utilizes satellite images from Landsat 4TM, Landsat 7 ETM+, and Landsat 8 OLI taken between 1991 and 2020. Data pre-processing techniques using ENVI 5.3 included calibration, layer stacking, mosaicking, and supervised classification. Post-classification shorelines were extracted using ArcGIS 10.7, and the DSAS tool was used to determine the rate of change over the 29-year period. The results showed that the coastline experienced an average erosion rate of 9 m/y and a maximum rate of 24 m/y, however, the accretion rate (3 m/y) was much lower, reflecting general coastline retreat. Thus, some 25 coastal communities are highly exposed to shoreline erosion. Sustaining the coastal area may require coastline re-engineering interventions. This study recommends continuous monitoring of the shorelines to ensure the protection of livelihoods. Implementation of both hard engineering and ecosystem-based adaptation strategies may be required to achieve holistic results toward sustainable coastal management.

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Cary, Jeffrey W., Kenneth C. Ehrlich, John M. Bland, and Beverly G. Montalbano. "The Aflatoxin Biosynthesis Cluster Gene, aflX, Encodes an Oxidoreductase Involved in Conversion of Versicolorin A to Demethylsterigmatocystin." Applied and Environmental Microbiology 72, no. 2 (February 2006): 1096–101. http://dx.doi.org/10.1128/aem.72.2.1096-1101.2006.

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ABSTRACT Biosynthesis of the toxic and carcinogenic aflatoxins by the fungus Aspergillus flavus is a complicated process involving more that 27 enzymes and regulatory factors encoded by a clustered group of genes. Previous studies found that three enzymes, encoded by verA, ver-1, and aflY, are required for conversion of versicolorin A (VA), to demethylsterigmatocystin. We now show that a fourth enzyme, encoded by the previously uncharacterized gene, aflX (ordB), is also required for this conversion. A homolog of this gene, stcQ, is present in the A. nidulans sterigmatocystin (ST) biosynthesis cluster. Disruption of aflX in Aspergillus flavus gave transformants that accumulated ∼4-fold more VA and fourfold less aflatoxin than the untransformed strain. Southern and Northern blot analyses confirmed that aflX was the only gene disrupted in these transformants. Feeding ST or O-methylsterigmatocystin, but not VA or earlier precursor metabolites, restored normal levels of AF production. The protein encoded by aflX is predicted to have domains typical of an NADH-dependent oxidoreductase. It has 27% amino acid identity to a protein encoded by the aflatoxin cluster gene, aflO (avfA). Some of domains in the protein are similar to those of epoxide hydrolases.

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Ptok, U., A. Papassotiropoulos, W. Maier, and R. Heun. "Distribución estacional de los nacimientos en pacientes con la enfermedad de Alzheimer y pacientes depresivos mayores." European psychiatry (Ed. Española) 8, no. 6 (September 2001): 378–83. http://dx.doi.org/10.1017/s113406650000655x.

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ResumenLos nacimientos en invierno se han asociado con un riesgo más elevado de enfermedad de Alzheimer (EA) y otros trastornos psiquiátricos. En la presente investigación, se examinó esta asociación putativa en una muestra de pacientes gerontopsiquiátricos. Un análisis de las tasas de nacimiento trimestrales de 83 pacientes con EA, 78 pacientes depresivos mayores con comienzo temprano del trastorno depresivo y 74 pacientes con comienzo tardío, 48 pacientes con EA y depresión a la vez (pacientes comórbidos) y 107 sujetos de control sanos no reveló una distribución estacional particular para ninguno de los grupos diagnósticos. En los pacientes con EA y comórbidos, controlar el genotipo de la ApoE no cambió este hallazgo. El análisis de regresión matemática reveló los hallazgos esperados de que la mayor edad y la presencia del alelo ApoE4 se asociaban con un riesgo más elevado de demencia. La menor edad y el género femenino se identificaron como factores de riesgo para trastorno depresivo. Haber nacido en invierno (en los tres primeros meses del aflo) no se asociaba con ninguno de los subgrupos diagnóstics. Concluimos que, en nuestra muestra, no se encontró que una distribución estacional de los nacimientos aumentara el riesgo para EA o depresión geriátrica.

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Corrêa, Janaína Viana. "O conforto que veio do traçado das crianças de terreiro." Revista Docência e Cibercultura 5, no. 2 (July 12, 2021): 317–26. http://dx.doi.org/10.12957/redoc.2021.60617.

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A pandemia da COVID-19 que assolou nosso planeta, trouxe consequências drásticas para as famílias e uma delas foi o isolamento social. Vários foram as estratégias ao redor do mundo de fazer com que esse afastamento não virasse patologia, músicas na janela, “chuva” de lives, recebidos e muitas vídeo-chamadas. O presente trabalho tem por objetivo dialogar com os desenhos que as crianças do terreiro Omi Larè Iya [1]Sagbá fizeram nesse período. A ideia era que as crianças fizessem desenhos dos seus respectivos orixás e compartilhassem no grupo de Watsap do asé, seria um afago para as pessoas do terreiro ver imagens produzidas pelas crianças com mensagens de que ficaria tudo bem. Segundo Beniste o “orixá são divindades representadas pela energia da natureza, forças que alimentam a vida a terra, agindo de forma intermediária entre Deus e as pessoas”. Logo o acolhimento vai vir das matas, das águas doces e salgadas, da terra, da chuva, dos raios e trovões. Para Sarmento “o desenho infantil comunica, as imagens são evocativas e referências de modo distinto e para além do que a linguagem verbal pode fazer”. Assim vai seguir este trabalho além do verbal. [1] Nome do terreiro onde foi feito o trabalho que quer dizer “Casa da força vital do herdeiro das águas de mãe Sagba”

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Wang, Kai, Pei-sheng Yan, Li-xin Cao, Qing-long Ding, Chi Shao, and Teng-fei Zhao. "Potential of ChitinolyticSerratia marcescensStrain JPP1 for Biological Control ofAspergillus parasiticusand Aflatoxin." BioMed Research International 2013 (2013): 1–7. http://dx.doi.org/10.1155/2013/397142.

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Serratia marcescensstrain JPP1 was isolated from peanut hulls in Huai'an city, Jiangsu Province, China. Its potential to inhibit the mycelial growth ofAspergillus parasiticusand the subsequent aflatoxin production was evaluated. The strain JPP1 could produce chitinase to degrade fungal cell walls, which was the main mechanism of strain JPP1 for biocontrol. Scanning electron microscopy of fungi treated with the crude chitinase revealed abnormal morphological changes. While the strain was grown in the peanut hulls-based medium, the chitinase activity reached 7.39 units. RT-PCR analysis showed that the crude chitinase repressed the transcription of genes involved in the aflatoxin gene cluster, such as aflR, aflC (pksL1), and aflO (dmtA) genes. By visual agar plate assay and tip culture method, the strain JPP1 exhibited remarkable inhibitory effect on mycelia growth (antifungal ratio >95%) and subsequent aflatoxin production (antiaflatoxigenic ratio >98%). Anin vitroassay with seed coating agent of bacterial suspension showed that strain JPP1 effectively reduced fungal growth and subsequent aflatoxin production on peanut seeds, and its antagonistic effect was superior to the common agricultural fungicide of carbendazim. These characteristics suggest thatS. marcescensJPP1 strain could potentially be utilized for the biological control of phytopathogenic fungi and aflatoxin in Chinese peanut main producing areas.

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Cannone, Lara Araújo Roseira, Ananda Evelin Genonádio da Silva Menezes, Lucas Almeida Santana Rocha, Saulo Leal Merelles, Maria Thereza Ávila Dantas Coelho, and Milena Pereira Pondé. "PERSONALIDADE DAS MÃES E GRAVIDADE DE SINTOMAS DE TRANSTORNO DO ESPECTRO DO AUTISMO NOS FILHOS." Revista Psicologia, Diversidade e Saúde 6, no. 2 (May 31, 2017): 66. http://dx.doi.org/10.17267/2317-3394rpds.v6i2.1197.

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Introdução: Estudo prévio indica que a gravidade dos sintomas de TEA nos filhos parece estar positivamente associada com a gravidade dos sintomas de depressão e ansiedade de pais de crianças com TEA. Esse estudo tem como objetivo analisar a associação entre traços de personalidade das mães e gravidade dos sintomas de TEA nos filhos. Metodologia: a amostra do estudo foi selecionada entre pais de crianças diagnosticadas com autismo em instituições de atendimento a pessoas com TEA. As crianças foram diagnosticadas por profissionais da psiquiatria, segundo os critérios do DSM-5. No total foram incluídas 54 mães. O instrumento utilizado para avaliar os traços de personalidade das mães foi o Inventário Fatorial de Personalidade (IFP). Resultados: alguns traços de personalidade se apresentaram de forma diferentes em mães de crianças com TEA Leve em relação a mães de crianças de sintomas de TEA Moderado ou Grave, especificamente intercepção, deferência, desempenho, exibição, autonomia e ordem. Os traços de assistência, afago, afiliação, agressão e mudança apresentaram baixa expressão em ambos os grupos. O traço de persistência foi o que apresentou maior prevalência de escores elevados nos dois grupos. Conclusão: Apesar de ser um estudo preliminar, com amostra pequena e sem grupo de comparação, este estudo pode servir como indicador para pesquisas futuras com populações maiores que possam esclarecer de forma mais confiável a associação entre traços de personalidade das mães e gravidade dos sintomas nos filhos com diagnóstico de TEA.

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Hoth, Alanis Fonseca, and Ewerthon Macedo Ribeiro. "Vida animal: a impunidade gerando crueldades." Research, Society and Development 11, no. 14 (November 3, 2022): e481111436576. http://dx.doi.org/10.33448/rsd-v11i14.36576.

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Hodierno artigo, perante afago e preocupação com a vida animal, propendeu-se a discutir, enquanto objetivo geral, os fatores que contribuem, pontualmente, para a crueldade em desfavor dos animais. Deste, emergiu os específicos, consistindo em contextualizar brevemente a evolução histórica no que tange as conquistas legais dos animais, produzir uma análise técnica de natureza material e processual do direito animal brasileiro e investigar o que motiva e no que resulta a crueldade e o desamparo animal, em seio legislacional, processual, administrativo e social. Este artigo desenvolveu levantamento bibliográfico através da leitura e análise de autores que debatem sobre o tema. Para a obtenção dos presentes dados foram consultados livros, revistas, artigos e periódicos publicados. Em síntese, os resultados, provenientes da lei, da aplicação processual, os de cunho administrativo e social, mostraram-se um tanto quanto suficientes, a ponto de elucidar as razões pelas quais este cenário se estagnara e se tornara “normal”, pois, o que, em suma, ocorre na prática, é de tais cruéis condutas não serem rebatidas da forma que fazem jus. O que, notoriamente, somente alerta a urgência com que este cenário merece mudar, considerando que, pelo fato de os animais configurarem seres sencientes, assim dizendo, possuem sensações, sensibilidade, sofrimento físico e mental, condutas criminosas, que torturam, machucam, deixam sequelas (por vezes, irremediáveis), não podem simplesmente serem menosprezadas, ou ainda tratadas - legalmente, processualmente, administrativamente e socialmente - com tamanho desinteresse e desleixo.

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Jamali, Mojdeh, Morteza Karimipour, Masoomeh Shams-Ghahfarokhi, Akram Amani, and Mehdi Razzaghi-Abyaneh. "Expression of aflatoxin genes aflO (omtB) and aflQ (ordA) differentiates levels of aflatoxin production by Aspergillus flavus strains from soils of pistachio orchards." Research in Microbiology 164, no. 4 (May 2013): 293–99. http://dx.doi.org/10.1016/j.resmic.2012.12.008.

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Minetto, Ariete Ines, Kristian Madeira, Robson Pacheco, Kelen Gava Duminelle, Elisa Da Silva Bobsin, and Joice De Abreu Brandolfi. "ATUAÇÃO FISIOTERAPÊUTICA PARA REDUÇÃO DO QUADRO ÁLGICO NO TRABALHO DE PARTO ATIVO." Inova Saúde 6, no. 2 (April 9, 2018): 20. http://dx.doi.org/10.18616/is.v6i2.2554.

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A Fisioterapia no trabalho de parto, como forma de assistência à saúde da mulher, apresenta-se em ascensão. Trata-se de uma intervenção no ambiente onde se encontra a gestante, que necessita de cuidados e orientações sobre posicionamento, educação para o parto e medidas de alívio em caso de dor. O estudo teve como objetivo a promoção da redução do quadro álgico através da intervenção fisioterapêutica em gestantes em trabalho de parto ativo do Centro Obstétrico de um Hospital do Sul de Santa Catarina (SC). A amostra foi dividida em dois grupos sendo o Grupo 1 (G1), que recebeu a aplicação de um protocolo fisioterapêutico, baseado nas condutas de terapia manual e adoção de posturas verticais e o Grupo 2 (G2), que compôs o grupo placebo, o qual recebeu apenas afago, ou seja, simulação de tratamento. Participaram da pesquisa 16 gestantes, com idade média de 24,69 anos (± 5,49). Para a graduação da dor foi utilizada a Escala Visual Analógica (EVA). Nas aplicações da escala EVA durante o tempo de trabalho de parto ativo, percebeu-se que em média, a dor das gestantes do G1 foi menor que a das gestantes do G2 a partir de 60 minutos. Possibilitando a conclusão de que, a abordagem fisioterapêutica junto à equipe de centros obstétricos é benéfica, atuando em orientações quanto a mobilidade adequada à gestante, aderindo o uso de posturas verticais bem como o uso de técnicas de terapia manual, influenciando de maneira positiva na fase ativa do trabalho de parto, diminuindo a dor e o tempo do trabalho de parto, demonstrando a relevância desse estudo.

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Ameke, Selassie, Prince Asare, Samuel Yaw Aboagye, Isaac Darko Otchere, Stephen Osei-Wusu, Dorothy Yeboah-Manu, and Adwoa Asante-Poku. "Molecular epidemiology of Mycobacterium tuberculosis complex in the Volta Region of Ghana." PLOS ONE 16, no. 3 (March 17, 2021): e0238898. http://dx.doi.org/10.1371/journal.pone.0238898.

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Context Available molecular epidemiological data from recent studies suggest significant genetic variation between the different lineages of Mycobacterium tuberculosis complex (MTBC) and the MTBC lineages might have adapted to different human populations. Aim This study sought to determine the population structure of clinical MTBC isolates from the Volta Region of Ghana. Methods The MTBC isolates obtained from collected sputum samples were identified by PCR detecting of IS6110 and genotyped using spoligotyping. Non-tuberculous mycobacterial isolates were characterized by amplification of the heat shock protein 65 (hsp65) gene and sequencing. The drug susceptibility profiles of the MTBCs determined using GenoType MTBDRplus. Results One hundred and seventeen (117, 93.6%) out of 125 mycobacterial positive isolates were characterized as members of the MTBC of which M. tuberculosis sensu stricto (MTBss) and M. africanum (MAF) were respectively 94 (80.3%) and 23 (19.7%). In all, 39 distinct spoligotype patterns were obtained; 26 for MTBss and 13 for MAF lineages. Spoligotyping identified 89 (76%) Lineage 4, 16 (13.6%) Lineage 5, 7 (6.0%) Lineage 6, 3 (2.6%) Lineage 2, 1(0.9%) Lineage 3 and 1 (0.9%) Lineage 1. Among the Lineage 4 isolates, 62/89 (69.7%) belonged to Cameroon sub-lineage, 13 (14.7%) Ghana, 8 (9.0%) Haarlem, 2 (2.2%) LAM, 1 (1.1%) Uganda I, 1 (1.1%) X and the remaining two (2.2%) were orphan. Significant localization of MAF was found within the Ho municipality (n = 13, 29.5%) compared to the more cosmopolitan Ketu-South/Aflao (n = 3, 8.3%) (p-value = 0.017). Eight (8) non-tuberculous mycobacteria were characterized as M. abscessus (7) and M. fortuitum (1). Conclusion We confirmed the importance of M. africanum lineages as a cause of TB in the Volta region of Ghana.

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Moradi, M., H. Zamanizadeh, S. R. Fani, and E. Sedaghati. "SPECIFIC IDENTIFICATION OF ATOXIGENIC STRAINS OF ASPERGILLUS FLAVUS ISOLATED FROM PISTACHIO ORCHARDS OF IRAN AND DETECTION OF AFLD, AFLR, AFLJ, AFLG GENES AND C3 REGION." Acta Horticulturae, no. 963 (October 2012): 95–97. http://dx.doi.org/10.17660/actahortic.2012.963.15.

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Liu, Jiajian, and Peter Zuber. "A Molecular Switch Controlling Competence and Motility: Competence Regulatory Factors ComS, MecA, and ComK Control ςD-Dependent Gene Expression in Bacillus subtilis." Journal of Bacteriology 180, no. 16 (August 15, 1998): 4243–51. http://dx.doi.org/10.1128/jb.180.16.4243-4251.1998.

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ABSTRACT Bacillus subtilis, like many bacteria, will choose among several response pathways when encountering a stressful environment. Among the processes activated under growth-restricting conditions are sporulation, establishment of motility, and competence development. Recent reports implicate ComK and MecA-ClpC as part of a system that regulates both motility and competence development. MecA, while negatively controlling competence by inhibiting ComK, stimulates ςD-dependent transcription of genes that function in motility and autolysin production. Both ComK-dependent and -independent pathways have been proposed for MecA’s role in the regulation of motility. Mutations in mecA reduce the transcription of hag. encoding flagellin, and are partially suppressed by comK in both medium promoting motility and medium promoting competence. Reduced ςD levels are observed in mecA mutants grown in competence medium, but no change in ςD concentration is detected in acomK mutant. The comF operon, transcription of which requires ComK, is located immediately upstream of the operon that contains the flgM gene, encoding the ςD-specific antisigma factor. An insertion mutation that disrupts the putative comF-flgM transcription unit confers a phenotype identical to that of the comK mutant with respect to hag-lacZ expression. Expression of aflgM-lacZ operon fusion is reduced in both sigDand comK mutant cells but is abolished in the sigD comK double mutant. Reverse transcription-PCR examination of thecomF-flgM transcript indicates that readthrough fromcomF into the flgM operon is dependent on ComK. ComK negatively controls the transcription of hag by stimulating the transcription of comF-flgM, thereby increasing the production of the FlgM antisigma factor that inhibits ςD activity. There likely exists anothercomK-independent mechanism of hag transcription that requires mecA and possibly affects the ςD concentration in cells undergoing competence development.

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Shahi, A., N. Gautam, S. Rawal, U. Sharma, and A. Jayan. "Lipid Profile and Ultrasonographic Grading in Alcoholic and Non Alcoholic Fatty Liver Patients." Kathmandu University Medical Journal 19, no. 3 (September 30, 2021): 334–38. http://dx.doi.org/10.3126/kumj.v19i3.49712.

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Background Fatty liver disease (FLD) is a common and major chronic liver disease. It has been implicated that patients have disorders of lipid metabolism and are involved in the pathogenesis of fatty liver. Hence, it was designed to observe the association between lipid profile and fatty liver disease. Objective This study was undertaken to evaluate the association of lipid profile status, hemoglobin and albumin levels with fatty liver disease patients diagnosed based on ultrasonography (USG). Method This Cross-sectional study was undertaken in the Department of Internal Medicine with the collaboration of the Department of Radiology and Department of Biochemistry, Universal College of Medical Sciences-Teaching Hospital (UCMS-TH), Bhairahawa, Nepal from March 2019 to February 2020 in a total of 100 patients diagnosed with fatty liver disease by ultrasonography. The fasting blood was collected for lipid profile and carried out in the automated analyzer following standard protocol. Result In 100 cases, the male to female ratio was 1.8:1. Fifty six percent of the total cases presented with alcoholic fatty liver disease (AFLD) while the remaining 44% with non-alcoholic fatty liver disease (NAFLD). The spectrum of lipid abnormality was observed with increased total cholesterol (TC), Low Density Lipoprotein (LDL), increased triglycerides (TG), Very Low Density Lipoprotein (VLDL) in alcoholic fatty liver disease cases as compared to non-alcoholic fatty liver disease cases. However, it has been observed that TG/HDL and Non-HDL/HDL were higher in non-alcoholic fatty liver disease as compared to alcoholic fatty liver disease. Moreover, a statistically significant difference was observed in HDL between AFLG2 and NAFLG2 (p-value: 0.012). Conclusion Dyslipidemia and decreased HDL have been implicated in fatty liver diseases. USG in conjunction with Non-HDL/HDL, TG/HDL, hemoglobin, and albumin can be useful in early screening and monitoring of dyslipidemia in fatty liver patients.

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Accinelli, Cesare, H. K. Abbas, R. M. Zablotowicz, and J. R. Wilkinson. "Aspergillus flavus aflatoxin occurrence and expression of aflatoxin biosynthesis genes in soil." Canadian Journal of Microbiology 54, no. 5 (May 2008): 371–79. http://dx.doi.org/10.1139/w08-018.

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The carcinogen aflatoxin B1 (AFB1) produced by Aspergillus flavus is a major food safety concern in crops. However, information on AFB1 occurrence in soil and crop residue is scarce. A series of experiments investigated the occurrence of AFB1 in soil and corn residues and ascertained the ecology of A. flavus in a Dundee silt loam soil. Samples of untilled soil (0–2 cm) and residues were collected in March 2007 from plots previously planted with a corn isoline containing the Bacillus thuringiensis (Bt) endotoxin gene or the parental non-Bt isoline. AFB1 levels were significantly different in various corn residues. The highest AFB1 levels were observed in cobs containing grain, with 145 and 275 ng·g–1in Bt and non-Bt, respectively (P ≥ F = 0.001). Aflatoxin levels averaged 3.3 and 9.6 ng·g–1in leaves and (or) stalks and cobs without grain, respectively. All soils had AFB1 ranging from 0.6 to 5.5 ng·g–1with similar levels in plots from Bt and non-Bt corn. Based on cultural methods, soil contained from log103.1 to 4.5 A. flavus cfu·g–1with about 60% of isolates producing aflatoxin. Laboratory experiments demonstrated that AFB1 is rapidly degraded in soil at 28 °C (half-life ≤ 5 days). The potential of the soil A. flavus to produce aflatoxins was confirmed by molecular methods. Transcription of 5 aflatoxin biosynthesis genes, including aflD, aflG, aflP, aflR, and aflS, were detected by reverse transcription – polymerase chain reaction analysis in soil. Although AFB1 appears to be transient in soils, it is clear that AFB1 is produced in surface soil in the presence of corn residues, as indicated by A. flavus cfu levels, AFB1 detection, and expression of aflatoxin biosynthetic genes.

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Ren, Xianfeng, Maria Teresa Branà, Miriam Haidukowski, Antonia Gallo, Qi Zhang, Antonio F. Logrieco, Peiwu Li, Shancang Zhao, and Claudio Altomare. "Potential of Trichoderma spp. for Biocontrol of Aflatoxin-Producing Aspergillus flavus." Toxins 14, no. 2 (January 23, 2022): 86. http://dx.doi.org/10.3390/toxins14020086.

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The inhibitory action of 20 antagonistic Trichoderma isolates against the aflatoxigenic isolate A. flavus ITEM 9 (Af-9) and their efficacy in reducing aflatoxin formation in vitro were examined. Production of metabolites with inhibitory effect by the Trichoderma isolates was also investigated. Antagonistic effect against Af-9 was assessed by inhibition of radial growth of the colonies and by fungal interactions in dual confrontation tests. A total of 8 out of 20 isolates resulted in a significant growth inhibition of 3-day-old cultures of Af-9, ranging from 13% to 65%. A total of 14 isolates reduced significantly the aflatoxin B1 (AfB1) content of 15-day-old Af-9 cultures; 4 were ineffective, and 2 increased AfB1. Reduction of AfB1 content was up to 84.9% and 71.1% in 7- and 15-day-old cultures, respectively. Since the inhibition of Af-9 growth by metabolites of Trichoderma was not necessarily associated with inhibition of AfB1 production and vice versa, we investigated the mechanism of reduction of AfB1 content at the molecular level by examining two strains: one (T60) that reduced both growth and mycotoxin content; and the other (T44) that reduced mycotoxin content but not Af-9 growth. The expression analyses for the two regulatory genes aflR and aflS, and the structural genes aflA, aflD, aflO and aflQ of the aflatoxin biosynthesis cluster indicated that neither strain was able to downregulate the aflatoxin synthesis, leading to the conclusion that the AfB1 content reduction by these Trichoderma strains was based on other mechanisms, such as enzyme degradation or complexation. Although further studies are envisaged to identify the metabolites involved in the biocontrol of A. flavus and prevention of aflatoxin accumulation, as well as for assessment of the efficacy under controlled and field conditions, Trichoderma spp. qualify as promising agents and possible alternative options to other biocontrol agents already in use.

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Abdel-Hadi, Ahmed, Markus Schmidt-Heydt, Roberto Parra, Rolf Geisen, and Naresh Magan. "A systems approach to model the relationship between aflatoxin gene cluster expression, environmental factors, growth and toxin production by Aspergillus flavus." Journal of The Royal Society Interface 9, no. 69 (August 31, 2011): 757–67. http://dx.doi.org/10.1098/rsif.2011.0482.

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A microarray analysis was used to examine the effect of combinations of water activity ( a w , 0.995–0.90) and temperature (20–42°C) on the activation of aflatoxin biosynthetic genes (30 genes) in Aspergillus flavus grown on a conducive YES (20 g yeast extract, 150 g sucrose, 1 g MgSO 4 ·7H 2 O) medium. The relative expression of 10 key genes ( aflF , aflD , aflE , aflM , aflO , aflP , aflQ , aflX , aflR and aflS ) in the biosynthetic pathway was examined in relation to different environmental factors and phenotypic aflatoxin B 1 (AFB 1 ) production. These data, plus data on relative growth rates and AFB 1 production under different a w × temperature conditions were used to develop a mixed-growth-associated product formation model. The gene expression data were normalized and then used as a linear combination of the data for all 10 genes and combined with the physical model. This was used to relate gene expression to a w and temperature conditions to predict AFB 1 production. The relationship between the observed AFB 1 production provided a good linear regression fit to the predicted production based in the model. The model was then validated by examining datasets outside the model fitting conditions used (37°C, 40°C and different a w levels). The relationship between structural genes ( aflD , aflM ) in the biosynthetic pathway and the regulatory genes ( aflS , aflJ ) was examined in relation to a w and temperature by developing ternary diagrams of relative expression. These findings are important in developing a more integrated systems approach by combining gene expression, ecophysiological influences and growth data to predict mycotoxin production. This could help in developing a more targeted approach to develop prevention strategies to control such carcinogenic natural metabolites that are prevalent in many staple food products. The model could also be used to predict the impact of climate change on toxin production.

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Rahimi, Sepideh, Noshin Sohrabi, Mohammad Ali Ebrahimi, Majid Tebyanian, Morteza Taghi Zadeh, and Sahar Rahimi. "Application of PCR in the Detection of Aflatoxinogenic and Non-aflatoxinogenic Strains of Aspergillus Flavus Group of Cattle Feed Isolated in Iran." Journal of Molecular Biology Research 6, no. 1 (November 30, 2016): 121. http://dx.doi.org/10.5539/jmbr.v6n1p121.

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Aflatoxins are among the most important Mycotoxins that are mainly produced by various Aspergillus species, specially Aspergillus flavus and Aspergillus parasiticus. Aflatoxins are carcinogenetic and immunosuppressive, so that can lead to acute liver damage, cirrhosis of the liver and hepatocarcinoma induction. Consuming the feed contaminated by Aspergillus puts humans and animals under the danger of Aflatoxins that are considered as an important threats for human and animal health. The purpose of the present study was to make distinction between Aflatoxinogenetic and non-Aflatoxinogenetic strains and Aspergillus Flavus using PCR and TLC and the expression of five Aflatoxin biosynthesis genes including aflD (nor-1), aflP( omtA), aflO (omtB), aflQ(ordA), aflR in 40 strains was investigated using PCR. In this study, a number of 40 Aspergillus flavus strains from 67 species of cattle feed from 21 industrial warehouses of various areas of Tehran and Alborz were used. After isolation and culture in exclusive environment of yeast extract of sucrose agar, the isolated Aspergillus strains were investigated by microscopic and macroscopic methods. In order to make distinction between Aflatoxinogenetic and non-Aflatoxinogenetic strains, PCR method and TLC techniques were used. The results showed that only 7 strains (1, 3, 5, 14, 22, 34, and 38) were Aflatoxin-producers fungi and the rest 33 samples were non-Afatoxin-producers fungi. Since Aspergillus flavus is the main contaminator of cattle feed, there is a need to develop a simple, rapid and sensitive method to identify Aflatoxigenetic fungi, particularly between Aflatoxinogenetic and non-Aflatoxinogenetic strains of AF.

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Scherm, Barbara, Michele Palomba, Domenico Serra, Angela Marcello, and Quirico Migheli. "Detection of transcripts of the aflatoxin genes aflD, aflO, and aflP by reverse transcription–polymerase chain reaction allows differentiation of aflatoxin-producing and non-producing isolates of Aspergillus flavus and Aspergillus parasiticus." International Journal of Food Microbiology 98, no. 2 (February 2005): 201–10. http://dx.doi.org/10.1016/j.ijfoodmicro.2004.06.004.

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Gerasymchuk, V. R. "ASSESSMENT OF THE NEURONAL DAMAGE AND OXIDATIVE STRESS MARKERS LEVEL IN POST STROKE PATIENTS." Medical Science of Ukraine (MSU) 15, no. 3-4 (December 26, 2019): 48–53. http://dx.doi.org/10.32345/2664-4738.3-4.2019.07.

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Relevance. 100-110 000 acute disorders of cerebral circulation are registered in Ukraine annually, about 57% of which are ischemic stroke (IS). Study of dynamics of the neuronal damage markers level and their correlation with oxidative stress indicators may be informative for estimating the prognosis of the IS recovery period. Objective: to study the features of of neuronal damage markers level, the pro- and antioxidant systems status and their effect on the of neurological deficiency manifestations and the functional status of post stroke patients. Materials and methods. 120 patients in the early recovery period of first-ever hemispheric atherothrombotic IS were examined. The control group (CG) included 20 healthy individuals, representative by age and gender. Assessment of neurological deficiency and functional status of patients was performed with the help of the NIHSS scale, the Scandinavian Stroke Scale (SSS), the modified Rankin Scale (mRS) and the Bartel Index (BI). The level of neuron-specific enolase (NSE) in serum was determined by enzyme-linked immunosorbent assay. The determination of the level of oxidative protein modification (OPM) products in serum, glutathione reductase (GR) and glutathione peroxidase (GP) activity was performed spectrophotometrically. Statistical processing of the results was carried out using Statistica 6.0 statistical analysis package (StatSoft, Inc.) with the help of nonparametric results estimation methods. Results. In patients after 1 month after IS an increase of AFGn (356 nm) content by 33.9% (p<0.05) compared to CG was observed. KFGn (370 nm) level was increased by 26.0% (p<0.05), AFGo (430 nm) - by 76.2% (p<0.01), CFG (530 nm) - 125.0% (p<0.01). The general OPM products was 37.0% higher than in CG (p<0.05), while the activity of GP and GR decreased by 31.6% and 28.6%, respectively (p<0, 05), and the NSE level was increased by 150.6% (p<0.05). The NIHSS score correlated with the level of AFGn (356 nm) (r=0.24; p=0.032), KFGo (530 nm) (r=0.41; p=0.047) and the general OPM products level (r=0.25 ; p=0.039), whereas the GR activity significantly influenced the NIHSS score (r=-0.27; p=0.048), SSS score (r=0.23; p=0.034) and BI (r=0.31; p=0.038). Also significant correlations were found between the NSE level and the concentration of all OPM products, GP ans GR activity. Conclusions. The NSE level increase is characteristic for the post stroke patients, which correlates with the degree of neurological deficiency manifestations and the patients’ functional status. The NSE level increases due to the increase of OPM products concentration and the decrease of GP and GR activity, which may indicate a worsening of the neuronal damage degree, linked to the pro- and antioxidant systems imbalance. These processes adversely affect the functional status of patients, with the greatest influence of the KFGo (530 nm) concentration, the general OPM products level and the GR activity.

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Cao, Tianlin, Fanyu Zhao, Zulin Da, Fengxian Qiu, Dongya Yang, Yijun Guan, Guorong Cao, Zerun Zhao, Jiaxin Li, and Xiaotong Guo. "Synthesis of Amino-Functionalized Graphene Oxide/Azobenzene Polyimide and its Simulation of Optical Switches." Zeitschrift für Physikalische Chemie 231, no. 11-12 (January 1, 2017). http://dx.doi.org/10.1515/zpch-2016-0801.

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AbstractIn this work, an amino-functionalized graphene oxide (AFGO) was synthesized by graphene oxide (GO) and ethylene diamine. A novel amino-functionalized graphene oxide/azobenzene polyimide (AFGO/ACPI) was synthesized with AFGO, azobenzene chromophore and pyromellitic dianhydride (PMDA). The structure, mechanical and thermal property of AFGO/ACPI were characterized and measured by fourier transform infrared, UV-visible spectroscopy, near-infrared spectrum, thermogravimetric analysis and differential scanning calorimetry. To obtain the refractive index of AFGO/ACPI at different temperature and wavelength (532 nm, 650 nm and 850 nm), the attenuated total reflection (ATR) method was used to measure, and thermo optic coefficients (dn/dT) were −7.22×10

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Manakova, Elena, Edvardas Golovinas, Reda Pocevičiūtė, Giedrius Sasnauskas, Algirdas Grybauskas, Saulius Gražulis, and Mindaugas Zaremba. "Structural basis for sequence-specific recognition of guide and target strands by the Archaeoglobus fulgidus Argonaute protein." Scientific Reports 13, no. 1 (April 14, 2023). http://dx.doi.org/10.1038/s41598-023-32600-w.

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AbstractArgonaute (Ago) proteins are found in all three domains of life. The best-characterized group is eukaryotic Argonautes (eAgos). Being the structural core of RNA interference machinery, they use guide RNA molecules for RNA targeting. Prokaryotic Argonautes (pAgos) are more diverse, both in terms of structure (there are eAgo-like ‘long’ and truncated ‘short’ pAgos) and mechanism, as many pAgos are specific for DNA, not RNA guide and/or target strands. Some long pAgos act as antiviral defence systems. Their defensive role was recently demonstrated for short pAgo-encoding systems SPARTA and GsSir2/Ago, but the function and action mechanisms of all other short pAgos remain unknown. In this work, we focus on the guide and target strand preferences of AfAgo, a truncated long-B Argonaute protein encoded by an archaeon Archaeoglobus fulgidus. We demonstrate that AfAgo associates with small RNA molecules carrying 5′-terminal AUU nucleotides in vivo, and characterize its affinity to various RNA and DNA guide/target strands in vitro. We also present X-ray structures of AfAgo bound to oligoduplex DNAs that provide atomic details for base-specific AfAgo interactions with both guide and target strands. Our findings broaden the range of currently known Argonaute-nucleic acid recognition mechanisms.

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Emamgholi, Khosro, Shahram Moradi Dehaghi, Zahra Ranjbar, and Fereshteh motiee. "Amine functionalization of graphene oxide (AFGO) and corrosion behavior of epoxy-AFGO nanocomposites." Materials Chemistry and Physics, June 2022, 126339. http://dx.doi.org/10.1016/j.matchemphys.2022.126339.

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Golovinas, Edvardas, Danielis Rutkauskas, Elena Manakova, Marija Jankunec, Arunas Silanskas, Giedrius Sasnauskas, and Mindaugas Zaremba. "Prokaryotic Argonaute from Archaeoglobus fulgidus interacts with DNA as a homodimer." Scientific Reports 11, no. 1 (February 25, 2021). http://dx.doi.org/10.1038/s41598-021-83889-4.

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AbstractArgonaute (Ago) proteins are found in all three domains of life. The best-characterized group is eukaryotic Argonautes (eAgos), which are the core of RNA interference. The best understood prokaryotic Ago (pAgo) proteins are full-length pAgos. They are composed of four major structural/functional domains (N, PAZ, MID, and PIWI) and thereby closely resemble eAgos. It was demonstrated that full-length pAgos function as prokaryotic antiviral systems, with the PIWI domain performing cleavage of invading nucleic acids. However, the majority of identified pAgos are shorter and catalytically inactive (encode just MID and inactive PIWI domains), thus their action mechanism and function remain unknown. In this work we focus on AfAgo, a short pAgo protein encoded by an archaeon Archaeoglobus fulgidus. We find that in all previously solved AfAgo structures, its two monomers form substantial dimerization interfaces involving the C-terminal β-sheets. Led by this finding, we have employed various biochemical and biophysical assays, including SEC-MALS, SAXS, single-molecule FRET, and AFM, to show that AfAgo is indeed a homodimer in solution, which is capable of simultaneous interaction with two DNA molecules. This finding underscores the diversity of prokaryotic Agos and broadens the range of currently known Argonaute-nucleic acid interaction mechanisms.

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BEWIADZI, Samuel. "CHRONICLING GENDER-BASED ECONOMIC ACTIVITIES IN THE AFLAO-LOMÉ BORDERLAND (GHANA-TOGO)." Academia Letters, November 2, 2021. http://dx.doi.org/10.20935/al3856.

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Bomfim, Renata. "O beijo de sangue: a pós-modernidade do corpus hilstiano em Rútilo Nada." Revista Mosaicum, no. 6 (July 3, 2020). http://dx.doi.org/10.26893/rm.v3i6.387.

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Joalheira da linguagem, Hilda Hilst nos desafia com uma obra ora doce com um afago, ora terrível como um beijo de sangue. É assim que somos confrontados ao primeiro contato com Rútilo Nada. Prosa poética ganhadora do Prêmio Jabuti de 1994, fragmentada, composta por uma orquestração dissonante de vozes, Rútilo Nada se aproxima do teatro do absurdo de Ionesco e do teatro da crueldade de Beckett. Este estudo explora os caminhos obscuros/ luminosos do texto hilstiano buscando seus atravessamentos com os estudos da Pós-modernidade.

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De Sordi, Denise, Douglas Fávero, and Sérgio Morais. "“A ESCOLA DEVERIA SER AFAGO PRA GENTE”: OCUPAR E TORNAR A ESCOLA PÚBLICA." Revista da FAEEBA - Educação e Contemporaneidade 29, no. 58 (July 6, 2020). http://dx.doi.org/10.21879/faeeba2358-0194.2020.v29.n58.p290-307.

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K. Hlovor, Dr Ishmael. "Border Residents and Cross border Crimes in Ghana: An Empirical Study of Aflao." International Journal of Scientific Research and Management 6, no. 06 (June 15, 2018). http://dx.doi.org/10.18535/ijsrm/v6i6.sh01.

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Border residents have been noted for their involvement in goods smuggling and other illegal cross border exchanges as coping mechanisms for poverty and unemployment. This study assesses the veracity of this claim through a field survey of the eastern border town of Aflao. The result of the study shows that challenges of poverty and unemployment have forced border residents to exploit their location in the border space as coping strategy by engaging in officially proscribed activities. These activities involve crimes such as goods smuggling, smuggling facilitation, armed robbery and petty stealing, drug trafficking, human trafficking and arms trafficking. While border residents are likely to see some of these activities (armed robbery and petty stealing, drug trafficking, human trafficking and arms trafficking) as crimes, they would normally accept that goods smuggling and aiding smuggling are not crimes because they serve as livelihood options, which contribute to reducing unemployment and poverty in border areas. To be effective, border management has to be comprehensive and incorporate the livelihood needs of Borderlanders.

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Chachu, Sewoenam, and Tope Omoniyi. "Language Ideology and Practice on the Aflao-Lome Borderland: The Case of Two Border Schools." Journal of Borderlands Studies, October 14, 2020, 1–20. http://dx.doi.org/10.1080/08865655.2020.1824684.

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"Experimentation of waste sorting at the source for a better valorization: Case of Agbalepédogan and Aflao-Gakli districts in Lomé." Journal of Chemical, Biological and physical sciences 13, no. 1 (January 31, 2023). http://dx.doi.org/10.24214/jcbps.d.13.1.08499.

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Zhang, Yuxia, Haojie Liu, Menghan Liu, Xiaofan Ma, and Haifeng Shi. "Effects of different amine-functionalized graphene oxide on the mechanical and thermal properties of polyimide composites." High Performance Polymers, August 30, 2023. http://dx.doi.org/10.1177/09540083231199766.

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The utilization of functionalized graphene oxide as nanofillers has attracted significant attention in the development of high-performance composite materials. In this study, amine-functionalized graphene oxide (AFGO) by different amines, including p-phenylenediamine- (PPD-GO) and 4, 4’-diaminodiphenyl ether (ODA-GO), respectively, was prepared and used to synthesize a series of polyimide (PI) composite membranes via in situ polymerization method. The PPD-GO/PI and ODA-GO/PI composite membranes exhibited much higher mechanical and thermal properties than that of neat PI, owing to the diverse interfacial interaction and the surface architecture behavior. Compared to neat PI, the tensile strengths were enhanced 14.6% and 14.5%, the tensile modulus were enhanced 26.9% and 23.2%, and the Tg increased by 9°C and 17.5°C of the PI composite membrane containing 0.3 wt% PPD-GO or ODA-GO, respectively. This study provides a guidance for the development of high-performance PI composite materials through the regulated interfacial structure via the moderate chain length.

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Gomes, Marcela Andrade, Kátia Maheirie, and Bruna Corrêa. "JOVENS EM VULNERABILIDADES PSICOSSOCIAIS: GRUPO COMO LUGAR DE ACOLHIMENTO E SUBJETIVAÇÃO POLÍTICA." Psicologia em Estudo 27 (December 13, 2021). http://dx.doi.org/10.4025/psicolestud.v27i0.47375.

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Este artigo visa relatar uma experiência de estágio realizado em um Serviço de Convivência e Fortalecimento de Vínculos (SCFV) junto a jovens de periferias da cidade de Florianópolis (SC), de modo a problematizar as possibilidades e desafios do uso do dispositivo grupal como instrumento de intervenção psicossocial. Este serviço, vinculado à Proteção Social Básica da Política Nacional de Assistência Social (PNAS), tem como objetivo prevenir as situações de riscos e vulnerabilidades, bem como fortalecer os laços familiares e comunitários. Por meio da intervenção grupal, buscamos, junto com estes(as) jovens, criar um espaço de elaboração psíquica e política sobre temas significativos para suas vidas e para a atual sociedade. Apostamos na ideia de que as oficinas propiciaram a construção de um espaço coletivo que servisse de acolhimento ao sofrimento ético-político destes(as) jovens, subsidiando um afago às dores da vida e, também, servindo de catalisador aos processos de subjetivação política frente às iniquidades sociais que atravessam, sistematicamente, o cotidiano destes(as) jovens. Neste trabalho, trazemos reflexões em torno das potencialidades que o dispositivo grupal pode desencadear na constituição do sujeito, compreendendo-o como uma profícua ferramenta de intervenção psicossocial de escuta, acolhimento, fortalecimento comunitário e protagonismo político.

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Santos, Fernanda L. de Oliveira, and Silvana Augusta Barbosa Carrijo. "Porque o calor do afago dos braços teus traz-me de volta: o revisionismo dos contos de fadas na narrativa fílmica Frozen." Boletín Galego de Literatura, no. 51 (October 3, 2017). http://dx.doi.org/10.15304/bgl.51.3236.

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Journal articles on the topic 'AFLGo'

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