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This work shows how the tunnel-effect based magnetoresistance (TMR) technology can be used as a competitive sensing method in electrical current and power processors. The sensor is arranged in a Wheatstone bridge topology, and each magnetoresistance was composed of a series connection of 360 magnetic tunnel junction elements with the following structure (thickness in nm): 100 SiO2/5 Ta/15 Ru/5 Ta/15 Ru/5 Ta/5 Ru/20 IrMn/2 CoFe30/0.85 Ru/2.6 CoFe40B20/1.2 MgO/2 CoFe40B20/0.21 Ta/4 NiFe/0.20 Ru/6 IrMn/2 Ru/5 Ta/10 Ru. First, the electrical and thermal characteristics of the sensor were evaluated by analyzing its response to DC current sweeps at various temperatures, controlled using a climatic chamber. Nominal values of current sensitivity S (0.324 mV/A), bridge output offset voltage Vo,s,o (-37.1 mV), bridge input resistance Rinp,bridge (0.958 kΩ), and their thermal behavior were obtained (0.0036 mV/A°C, 0.079 mV/°C, and -0.31 Ω/°C). Second, an instrumentation system is introduced to characterize the sensor, measuring its sensitivity to AC line currents from the mains up to 10 Arms. Finally, an electronic wattmeter was developed showing the relevant quantities of its design. The circuit is able to interface a TMR Wheatstone bridge to an analog processor. Power and current measurements were obtained from a 150 Vrms AC mains 1.5 kW load with resistive and capacitive components, achieving less than 1% deviation over the expected values. The circuit shown can be used to interface these signals to more complex smart digital engines with active or reactive energy processing capabilities, while providing inherent high voltage isolation, thanks to its TMR measurement technology.
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Cassava (Manihot esculenta Crantz) is a staple crop widely cultivated by small farmers in tropical countries. However, despite the low level of technology required for its management, it can be affected by several diseases, with anthracnose as the main threat. There is little information about the main species of Colletotrichum that infect cassava in Brazil. Thus, the objective of this work was to study the diversity, prevalence and virulence of Colletotrichum species that cause anthracnose in cassava leaves in northern Brazil. Twenty municipalities of the Pará and Tocantins states were selected, and leaves with symptoms were collected in those locations. Pure cultures were isolated in the laboratory. Species were identified using phylogenetic analyses of multiple loci, and their pathogenicity, aggressivity and virulence levels were assessed. Our results showed the greatest diversity of Colletotrichum associated with anthracnose in cassava plants of the "Formosa" cultivar in the Tocantins and Pará states. We determined the presence of Colletotrichum chrysophilum, C. truncatum, C. siamense, C. fructicola, C. plurivorum, C. musicola and C. karsti, with C. chrysophilum as the most aggressive and virulent. Our findings provide accurate identifications of species of Colletotrichum causing anthracnose in cassava crops, which are of great relevance for cassava breeding programs (e.g., the search for genotypes with polygenic resistance since the pathogen is so diverse) and for developing anthracnose management strategies that can work efficiently against species complexes of Colletotrichum.
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Bacaba (Oenocarpus bacaba Mart.) is a native palm tree from Brazilian Amazon and Cerrado biomes. This tree produces a small, rounded fruit with dark skin and approximately 1.5 mm thick pulp, extensively utilized for palm heart extraction, juices, and jellies (De Cól et al. 2021). However, several diseases can adversely impact fruit yield and quality. During the 2021 growing season, anthracnose symptoms were observed in Bacaba fruits, with a disease incidence of 58% in fruits collected from the Abreulândia (9°37'15â³ S, 49°9'3â³ W) and Gurupi (12°25'46" S; 49°16'42" W) municipalities in Tocantins state, Brazil. A total of 198 fruits exhibiting anthracnose symptoms, characterized by deep necrotic spots, were collected. In the laboratory, symptomatic fruits had their external surfaces sterilized for 30 seconds in 70% ethanol, 1 min in 1.5% NaOCl, and then rinsed with sterile distilled water. Sterilized pieces of the fruit tissue were transferred to PDA medium and incubated for 7 days at 28 ºC with a 12 h photoperiod. After this period, two isolates were obtained from the colonies and were identified both macroscopically and microscopically as Colletotrichum sp. The colonies grown at PDA showed a white to grey cottony mycelia, with straight and fusiform conidia, ranging from 14.0 to 21.0 (mean value of 15.8 ± 1.8) µm in length and 4.0 to 7.0 (mean value of 5.5 ± 0.7) µm in width, (n = 50). For species identification, the intergenic spacer between DNA lyase, mating-type locus MAT1-2-1 (APN2/MAT-IGS), glyceraldehyde-3-phosphate dehydrogenase (GAPDH), glutamine synthetase (GS), and ß-tubulin (TUB) loci were amplified and sequenced. Resulting sequences were deposited in GenBank (OR333843, OR333844, OR333845 and OR333846). BLAST analysis of the partial APN2/MAT-IGS (99%), GAPDH (99,48%), GS (99,32%) and TUB (99,48%) sequences showed highly similarity to C. siamense isolates (IIFT223 and CBS130147). Maximum likelihood multilocus analysis placed the isolate UFTC16 within the C. siamense clade with 98% bootstrap support, clearly assigning the isolate to this species. Morphological features were consistent with the description of C. siamense (Prihastuti et al., 2009). Inoculation of Bacaba fruits and seedlings was conducted to confirm pathogenicity. The surface of uninjured Bacaba fruits was inoculated with two drops (20 µL) of conidial suspension (106 conidia mL-1). The same methodology was adopted to placed healthy leaves of 35-day-old seedlings grown in plastic tubes. Two drops of sterile distilled water were inoculated on nonwounded healthy fruits and seedlings as a negative control. The fruits and seedlings were incubated for five days in a controlled chamber at 28 °C, 70-80% humidity and a "12-h photoperiod". The experiment was conducted with five replicates (five fruits and five seedlings inoculated per isolate) and repeated once. Typical symptoms of anthracnose were observed in the fruits and leaves of Bacaba seedlings five days after inoculation. No symptoms were observed in the negative control. The pathogen was reisolated from symptomatic fruits and leaves, showing similar morphological characteristics as the original isolate, fulfilling Koch's postulates. The identification of C. siamense as the causal agent of Bacaba anthracnose helps in the diagnosis and disease control strategies of the disease. Colletotrichum siamense is a cosmopolitan species and easily found in cultivated and non-cultivated species (Batista et al. 2023). However, to the best of our knowledge, this is the first report of C. siamense causing anthracnose on Bacaba.
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BACKGROUND: Artificial intelligence in the field of orthopaedics has been a topic of increasing interest and opportunity in recent years. Its applications are widespread both for physicians and patients, including use in clinical decision-making, in the operating room, and in research. In this study, we aimed to assess the quality of ChatGPT answers when asked questions related to total knee arthroplasty. METHODS: ChatGPT prompts were created by turning 15 of the American Academy of Orthopaedic Surgeons Clinical Practice Guidelines into questions. An online survey was created, which included screenshots of each prompt and answers to the 15 questions. Surgeons were asked to grade ChatGPT answers from 1 to 5 based on their characteristics: (1) relevance, (2) accuracy, (3) clarity, (4) completeness, (5) evidence-based, and (6) consistency. There were 11 Adult Joint Reconstruction fellowship-trained surgeons who completed the survey. Questions were subclassified based on the subject of the prompt: (1) risk factors, (2) implant/intraoperative, and (3) pain/functional outcomes. The average and standard deviation for all answers, as well as for each subgroup, were calculated. Inter-rater reliability (IRR) was also calculated. RESULTS: All answer characteristics were graded as being above average (ie, a score > 3). Relevance demonstrated the highest scores (4.43 ± 0.77) by surgeons surveyed, and consistency demonstrated the lowest scores (3.54 ± 1.10). ChatGPT prompts in the Risk Factors group demonstrated the best responses, while those in the Pain/Functional Outcome group demonstrated the lowest. The overall IRR was found to be 0.33 (poor reliability), with the highest IRR for relevance (0.43) and the lowest for evidence-based (0.28). CONCLUSIONS: ChatGPT can answer questions regarding well-established clinical guidelines in total knee arthroplasty with above-average accuracy but demonstrates variable reliability. This investigation is the first step in understanding large language model artificial intelligence like ChatGPT and how well they perform in the field of arthroplasty.
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Artroplastia do Joelho , Humanos , Inquéritos e Questionários , Inteligência Artificial , Reprodutibilidade dos Testes , Ortopedia , Tomada de Decisão Clínica , Cirurgiões OrtopédicosRESUMO
Bacillus thuringiensis (Bt) is known for its Cry and Vip3A pesticidal proteins with high selectivity to target pests. Here, we assessed the potential of a novel neotropical Bt strain (UFT038) against six lepidopteran pests, including two Cry-resistant populations of fall armyworm, Spodoptera frugiperda. We also sequenced and analyzed the genome of Bt UFT038 to identify genes involved in insecticidal activities or encoding other virulence factors. In toxicological bioassays, Bt UFT038 killed and inhibited the neonate growth in a concentration-dependent manner. Bt UFT038 and HD-1 were equally toxic against S. cosmioides, S. frugiperda (S_Bt and R_Cry1 + 2Ab populations), Helicoverpa zea, and H. armigera. However, larval growth inhibition results indicated that Bt UFT038 was more toxic than HD-1 to S. cosmioides, while HD-1 was more active against Chrysodeixis includens. The draft genome of Bt UFT038 showed the cry1Aa8, cry1Ac11, cry1Ia44, cry2Aa9, cry2Ab35, and vip3Af5 genes. Besides this, genes encoding the virulence factors (inhA, plcA, piplC, sph, and chi1-2) and toxins (alo, cytK, hlyIII, hblA-D, and nheA-C) were also identified. Collectively, our findings reveal the potential of the Bt UFT038 strain as a source of insecticidal genes against lepidopteran pests, including S. cosmioides and S. frugiperda.
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Bacillus thuringiensis , Inseticidas , Mariposas , Animais , Humanos , Recém-Nascido , Bacillus thuringiensis/genética , Bacillus thuringiensis/metabolismo , Glycine max , Endotoxinas/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Proteínas Hemolisinas/genética , Proteínas Hemolisinas/metabolismo , Proteínas Hemolisinas/farmacologia , Inseticidas/farmacologia , Inseticidas/metabolismo , Spodoptera/metabolismo , Larva , Fatores de Virulência/metabolismo , Controle Biológico de VetoresRESUMO
Drosophila suzukii, an invasive insect pest, poses a significant threat to various fruit crops. The use of broad-spectrum insecticides to control this pest can reduce the effectiveness of biological control agents, such as the parasitoid Trichopria anastrephae. Here, we evaluated the toxicity of newly synthesized lactone derivatives on D. suzukii and their selectivity towards T. anastrephae. We used in silico approaches to identify potential targets from the most promising molecules in the D. suzukii nervous system and to understand potential differences in susceptibilities between D. suzukii and its parasitoid. Of the nine molecules tested, (rac)-8 and compound 4 demonstrated efficacy against the fly. Exposure to the estimated LC90 of (rac)-8 and compound 4 resulted in a mortality rate of less than 20% for T. anastrephae without impairing the parasitoid's functional parasitism. The in silico predictions suggest that (rac)-8 and compound 4 target gamma amino butyric acid (GABA) receptors and transient receptor potential (TRP) channels of D. suzukii. However, only the reduced interaction with TRP channels in T. anastrephae demonstrated a potential reason for the selectivity of these compounds on the parasitoid. Our findings suggest the potential for integrating (rac)-8 and compound 4 into D. suzukii management practices.
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Acinetobacter baumannii is a Gram-negative, immobile, aerobic nosocomial opportunistic coccobacillus that causes pneumonia, septicemia, and urinary tract infections in immunosuppressed patients. There are no commercially available alternative antimicrobials, and multi-drug resistance is an urgent concern that requires emergency measures and new therapeutic strategies. This study evaluated a multi-drug-resistant A. baumannii whole-cell vaccine, inactivated and adsorbed on an aluminum hydroxide-chitosan (mAhC) matrix, in an A. baumannii sepsis model in immunosuppressed mice by cyclophosphamide (CY). CY-treated mice were divided into immunized, non-immunized, and adjuvant-inoculated groups. Three vaccine doses were given at 0D, 14D, and 28D, followed by a lethal dose of 4.0 × 108 CFU/mL of A. baumannii. Immunized CY-treated mice underwent a significant humoral response, with the highest IgG levels and a higher survival rate (85%); this differed from the non-immunized CY-treated mice, none of whom survived (p < 0.001), and from the adjuvant group, with 45% survival (p < 0.05). Histological data revealed the evident expansion of white spleen pulp from immunized CY-treated mice, whereas, in non-immunized and adjuvanted CY-treated mice, there was more significant organ tissue damage. Our results confirmed the proof-of-concept of the immune response and vaccine protection in a sepsis model in CY-treated mice, contributing to the advancement of new alternatives for protection against A. baumannii infections.
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The use of formulations containing botanical products for controlling insects that vector human and animal diseases has increased in recent years. Plant extracts seem to offer fewer risks to the environment and to human health without reducing the application strategy's efficacy when compared to synthetic and conventional insecticides and repellents. Here, we evaluated the potential of extracts obtained from caninana, Chiococca alba (L.) Hitchc. (Rubiaceae), plants as a tool to be integrated into the management of Aedes aegypti, one of the principal vectors for the transmission of arborviruses in humans. We assessed the larvicidal and repellence performance against adult mosquitoes and evaluated the potential undesired effects of the extracts on non-target organisms. We assessed the susceptibility and predatory abilities of the nymphs of Belostoma anurum, a naturally occurring mosquito larva predator, and evaluated the C. alba extract's cytotoxic effects in mammalian cell lines. Our chromatographic analysis revealed 18 compounds, including rutin, naringin, myricetin, morin, and quercetin. The methanolic extracts of C. alba showed larvicidal (LC50 = 82 (72-94) mg/mL) activity without killing or affecting the abilities of B. anurum to prey upon mosquito larvae. Our in silico predictions revealed the molecular interactions between rutin and the AeagOBP1 receptor to be one possible mechanism for the repellent potential recorded for formulations containing C. alba extracts. Low cytotoxicity against mammalian cell lines reinforces the selectivity of C. alba extracts. Collectively, our findings highlight the potential of C. alba and one of its constituents (rutin) as alternative tools to be integrated into the management of A. aegypti mosquitoes.
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INTRODUCTION: Ketogenic therapy (KT) studies have focused in children older than 2 years and adults. Recently its efficacy in infants has been reported, but there are few studies in this age group. PATIENTS AND METHODS: We report a case series of nine newborn and children younger than 4 months of age with refractory epilepsy treated with KT. We retrospectively reviewed charts of children treated at our center between 2015-2021. RESULTS: Data was collected on seven patients. Six patients began having seizures on day one of life, one had seizures starting on day 45. Different epilepsy etiologies were found. KT was started as soon as 9 days of life. The average age at which ketogenic therapy was started was 24 days of life. Initially, the diet was started at 1:1 or 2:1 ratio, and was progressed to a 4:1 ratio. After one month of KT 5/7 patients experienced a significant reduction in seizure frequency (>50%) and 2/7 had complete seizure control. At six months, 4/7 patients achieve complete seizure freedom and 1/7 had >50% seizure reduction. Two patients were lost to follow-up. None of our patients reported gastrointestinal side effects that required diet adjustments. One patient had mild and one mild hypertriglyceridemia. CONCLUSION: Even though evidence about KT in young children are starting to emerge, our experience shows it can be successful in controlling seizure burden without considerable adverse effects. There is great research potential regarding KT in young children.
TITLE: Tolerancia y respuesta a la terapia cetógena en neonatos y lactantes menores de 4 meses. Serie de casos en un centro hospitalario de Medellín, Colombia.Introducción. Los estudios para terapia cetógena (TC) se han concentrado en niños mayores de 2 años y adultos. Su eficacia en lactantes se ha descrito, pero hay pocos estudios en este grupo de edad. Pacientes y métodos. Se describe una serie de casos de nueve neonatos y lactantes menores de 4 meses de edad con epilepsia refractaria que recibieron tratamiento con TC. Se evaluaron, retrospectivamente, los registros clínicos de niños tratados entre 2015 y 2021. Resultados. Se recolectaron datos de siete pacientes. Seis pacientes iniciaron con crisis epilépticas el primer día de vida, y uno, el día 45. La etiología de la epilepsia fue variada (metabólica, genética y estructural). La TC se inició tan temprano como a los 9 días de vida. La edad promedio de inicio fue los 24 días de vida. Se inició con una tasa cetógena de 1:1 o 1:2, y se progresó posteriormente a 4:1. Después de un mes de TC, 5/7 pacientes presentaron una reducción significativa en la frecuencia de las crisis (>50%) y 2/7 experimentaron un control completo. A los seis meses, 4/7 pacientes lograron un control completo y 1/7 un control >50%. Dos pacientes se perdieron en el seguimiento. No se notificaron efectos gastrointestinales que obligaran al ajuste o la suspensión de la dieta. Se notificaron hipoglucemia e hipertrigliceridemia. Conclusión. A pesar de que la evidencia en la TC en lactantes y neonatos apenas está empezando a aparecer, nuestra experiencia muestra que puede ser una buena opción terapéutica para el control de las crisis epilépticas, sin efectos adversos importantes. Existe un gran potencial de investigación en el área de la TC en lactantes y neonatos.
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Dieta Cetogênica , Epilepsia Resistente a Medicamentos , Criança , Lactente , Adulto , Recém-Nascido , Humanos , Pré-Escolar , Dieta Cetogênica/efeitos adversos , Estudos Retrospectivos , Colômbia , Resultado do Tratamento , Convulsões/etiologia , HospitaisRESUMO
Introducción: Los estudios para terapia cetógena (TC) se han concentrado en niños mayores de 2 años y adultos. Su eficacia en lactantes se ha descrito, pero hay pocos estudios en este grupo de edad. Pacientes y métodos: Se describe una serie de casos de nueve neonatos y lactantes menores de 4 meses de edad con epilepsia refractaria que recibieron tratamiento con TC. Se evaluaron, retrospectivamente, los registros clínicos de niños tratados entre 2015 y 2021. Resultados: Se recolectaron datos de siete pacientes. Seis pacientes iniciaron con crisis epilépticas el primer día de vida, y uno, el día 45. La etiología de la epilepsia fue variada (metabólica, genética y estructural). La TC se inició tan temprano como a los 9 días de vida. La edad promedio de inicio fue los 24 días de vida. Se inició con una tasa cetógena de 1:1 o 1:2, y se progresó posteriormente a 4:1. Después de un mes de TC, 5/7 pacientes presentaron una reducción significativa en la frecuencia de las crisis (>50%) y 2/7 experimentaron un control completo. A los seis meses, 4/7 pacientes lograron un control completo y 1/7 un control >50%. Dos pacientes se perdieron en el seguimiento. No se notificaron efectos gastrointestinales que obligaran al ajuste o la suspensión de la dieta. Se notificaron hipoglucemia e hipertrigliceridemia. Conclusión: A pesar de que la evidencia en la TC en lactantes y neonatos apenas está empezando a aparecer, nuestra experiencia muestra que puede ser una buena opción terapéutica para el control de las crisis epilépticas, sin efectos adversos importantes. Existe un gran potencial de investigación en el área de la TC en lactantes y neonatos.(AU)
Introduction: Ketogenic therapy (KT) studies have focused in children older than 2 years and adults. Recently its efficacy in infants has been reported, but there are few studies in this age group. Patients and methods: We report a case series of nine newborn and children younger than 4 months of age with refractory epilepsy treated with KT. We retrospectively reviewed charts of children treated at our center between 2015-2021. Results: Data was collected on seven patients. Six patients began having seizures on day one of life, one had seizures starting on day 45. Different epilepsy etiologies were found. KT was started as soon as 9 days of life. The average age at which ketogenic therapy was started was 24 days of life. Initially, the diet was started at 1:1 or 2:1 ratio, and was progressed to a 4:1 ratio. After one month of KT 5/7 patients experienced a significant reduction in seizure frequency (>50%) and 2/7 had complete seizure control. At six months, 4/7 patients achieve complete seizure freedom and 1/7 had >50% seizure reduction. Two patients were lost to follow-up. None of our patients reported gastrointestinal side effects that required diet adjustments. One patient had mild and one mild hypertriglyceridemia. CONCLUSION. Even though evidence about KT in young children are starting to emerge, our experience shows it can be successful in controlling seizure burden without considerable adverse effects. There is great research potential regarding KT in young children.(AU)
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Humanos , Recém-Nascido , Saúde da Criança , Dieta Cetogênica , Epilepsia Resistente a Medicamentos , Epilepsia Neonatal Benigna , Pacientes Internados , Exame Físico , Colômbia , Neurologia , Doenças do Sistema NervosoRESUMO
The use of plant-based products has been shown to efficiently inhibit fungi-mediated diseases in agricultural crops. Here, we extracted and evaluated the composition of noni, Morinda citrifolia L., essential oil and assessed its activities against Stagonosporopsis cucurbitacearum in Cucumis melo L. Using in silico molecular approaches, potential interactions between the essential oil major components and S. cucurbitacearum tyrosine-tRNA ligase were predicted. Finally, we also measured the potential interference of plant physiology (the stomatal conductance and net photosynthesis) mediated by the application of the M. citrifolia essential oil. Chromatographic analysis revealed that octanoic acid (75.8%), hexanoic acid (12.8%), and isobutyl pent-4-enyl carbonate (3.1%) were the major essential oil compounds. Octanoic acid and noni essential oil, when used as preventive measures, reduce fungal mycelial growth at a concentration of 5 mg/mL without causing significant damage to the treated leaves, which reinforces their efficacies as preventive tools against S. cucurbitacearum. Molecular docking analyses predicted very stable interactions between the major essential oil constituents and S. cucurbitacearum tyrosine-tRNA ligase, suggesting the interference of these plant-based molecules upon enzyme activation. Octanoic acid and M. citrifolia essential oil at concentrations of 20 mg/mL decreased the stomatal conductance and net photosynthesis rate of melon plants, resulting in robust phytotoxicity. Collectively, our findings indicated that despite the phytotoxicity risks at higher concentrations, M. citrifolia essential oil and octanoic acid, have potential as alternative tools for the integrative management of S. cucurbitacearum.
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Morinda , Óleos Voláteis , Tirosina-tRNA Ligase , Ascomicetos , Caprilatos , Simulação de Acoplamento Molecular , Morinda/química , Óleos Voláteis/farmacologia , Extratos Vegetais/químicaRESUMO
Cassava (Manihot esculenta) is one of the main food sources of energy in developing countries owing to its starch-rich roots (Pinweha et al., 2015). Anthracnose is considered the most destructive disease of the aerial part of this crop (Bragança et al., 2016; Liu et al., 2019), and it is caused by species such as Colletotrichum plurivorum, C. karstii, C. fructicola, C. siamense (Liu et al., 2019), and C. theobromicola (Oliveira et al, 2016). In 2019, leaves with irregular necrotic spots, typical symptoms of anthracnose, were collected in Pará, Brazil. Commercial sampled fields showed 20% of incidence of anthracnose. Colletotrichum strains were isolated and cultured on potato dextrose agar at 25 ºC with a 12-h light photoperiod from surface-disinfected (70% alcohol and 1% sodium hypochlorite) lesion transition area. Five of the obtained isolates exhibited brown colonies on the upper and lower surfaces. Conidia were hyaline, cylindrical and aseptate, 12.82-15.23 µm × 3.52-5.25 µm in size. These phenotypic characters were similar to those belonging to C. orchidearum sensu lato (Damm et al. 2019). Glyceraldehyde 3-phosphate dehydrogenase (GAPDH), ß-tubulin (TUB2), chitin synthase 1(CHS-1), and histone HIS3 partial gene were amplified and sequenced for one representative isolate (UFT/Coll89). Sequences were deposited in GenBank [Accession numbers: MT396235 (GAPDH), MT800856 (TUB2), MT800870 (CHS-1), and MT856672 (HIS3)]. BLASTn searches of CHS-1 and HIS3 sequences showed 100% identity to C. musicola. Maximum Likelihood Phylogenetic analysis, including previously published sequences of closely related species, placed the isolate from Cassava in the C. musicola clade with 100% support, and confidently it assigned to this species. Pathogenicity was proven with inoculations by spraying a conidial suspension (106 conida mL-1) on 3-month-old cassava plants (three unwounded leaves per plant). The plants were placed in a humid chamber at 25 °C for 48h, and a 12-h photoperiod. The negative control was represented by plants inoculated with sterile distilled water. The experiment was repeated twice. The same symptoms observed in the field were reproduced only in inoculated leaves, from which the pathogen was reisolated lesions fulfilling Koch's postulates. No symptoms were observed on the negative control. To our knowledge, this is the first report of C. musicola joining a group of new and emergent species of Colletotrichum causing anthracnose in cassava producing regions around the world. The identification of this species causing cassava anthracnose is crucial to improve the disease control strategies and resistance breeding programs.
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Fermentation of grape must to wine is carried out by a complex microbial mixture, which also involves spoilage yeasts of wine. The latter yeasts produce organoleptic changes that cause significant economic losses to the wine industry. SO2 is traditionally used to control this spoilage populations, but because of its harmful effects on human health, biocontrol has emerged as an alternative treatment. Although studies have been carried out to select biocontroller yeasts and examine their underlying mechanisms of action, reports on their application have not been published yet. To better understand the interaction and the successful application of biocontrol, the use of mathematical models, among other methods, is important, as they facilitate the prediction of success or failure of the antagonist. The objective of the present study was to use an existing mathematical model to obtain information about the yeast's interaction assayed and to validate its predictive use under different physicochemical conditions during the wine fermentation, and eventually predict biocontrol kinetics. The mathematical model was applied to the fermentation conditions and provided information on the kinetic parameters of the biocontrol interaction and allowed interpretations about other parameters. The model was applied in the different physicochemical conditions for the biocontrol and did not fit correctly to experimental data, and therefore an improvement was proposed which was successful and presented new hypotheses.