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Alternaria in Food: Ecophysiology, Mycotoxin Production and Toxicology

  • Lee, Hyang Burm;Patriarca, Andrea;Magan, Naresh
    • Mycobiology
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    • v.43 no.2
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    • pp.93-106
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    • 2015
  • Alternaria species are common saprophytes or pathogens of a wide range of plants pre- and post-harvest. This review considers the relative importance of Alternaria species, their ecology, competitiveness, production of mycotoxins and the prevalence of the predominant mycotoxins in different food products. The available toxicity data on these toxins and the potential future impacts of Alternaria species and their toxicity in food products pre- and post-harvest are discussed. The growth of Alternaria species is influenced by interacting abiotic factors, especially water activity ($a_w$), temperature and pH. The boundary conditions which allow growth and toxin production have been identified in relation to different matrices including cereal grain, sorghum, cottonseed, tomato, and soya beans. The competitiveness of Alternaria species is related to their water stress tolerance, hydrolytic enzyme production and ability to produce mycotoxins. The relationship between A. tenuissima and other phyllosphere fungi has been examined and the relative competitiveness determined using both an Index of Dominance ($I_D$) and the Niche Overlap Index (NOI) based on carbon-utilisation patterns. The toxicology of some of the Alternaria mycotoxins have been studied; however, some data are still lacking. The isolation of Alternaria toxins in different food products including processed products is reviewed. The future implications of Alternaria colonization/infection and the role of their mycotoxins in food production chains pre- and post-harvest are discussed.

Chromium(III) recovery from tanning wastewater by adsorption on activated carbon and elution with sulfuric acid

  • Hintermeyer, Blanca H.;Tavani, Eduardo L.
    • Environmental Engineering Research
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    • v.22 no.2
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    • pp.149-156
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    • 2017
  • Chromium(III) recovery from tanning wastewater by means of adsorption on activated carbon and elution with sulfuric acid was studied. Tests were carried out at laboratory scale on an effluent of industrial origin. Initially, proteinaceous materials and fats were separated via sieving followed by ultrafiltration. The chemical composition of the sample thus precleansed was (in g/L): 1.09 chromium(III); 10.36 sulfate; 11.10 sodium; 9.57 chloride; 0.40 proteinaceous materials; and 0.20 fats. Adsorptions were made at 20, 30, and $40^{\circ}C$, establishing what temperature favored chromium(III) uptake. At $40^{\circ}C$, the maximum cation fixation was 40.2 mg/g, and the lowest content in an equilibrium solution was 3.9 mg/L. As regards sodium, chloride, and sulfate, the concentrations before and after the treatment were similar. Likewise, it was found that protons were also retained, modifying the pH of the liquid medium. Adsorption isotherms were analyzed using the Langmuir, Temkin, and Freundlich models. Finally, the extraction of the adsorbed tanning agent with sulfuric acid was evaluated. A recovery of 96.5% was achieved with 0.9 N at $70^{\circ}C$ (13.23 g/L $Cr^{3+}$; 42.98 g/L sulfate; and 0.40 g/L NaCl).

Self-Feeder Driver for Voltage Balance in Series-Connected IGBT Associations

  • Guerrero-Guerrero, A.F.;Ustariz-Farfan, A.J.;Tacca, H.E.;Cano-Plata, E.A.
    • Journal of Power Electronics
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    • v.19 no.1
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    • pp.68-78
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    • 2019
  • The emergence of high voltage conversion applications has resulted in a trend of using semiconductor device series associations. Series associations allow for operation at blocking voltages, which are higher than the nominal voltage for each of the semiconductor devices. The main challenge with these topologies is finding a way to guarantee the voltage balance between devices in both blocking and switching transients. Most of the methods that have been proposed to mitigate static and dynamic voltage unbalances result in increased losses within the device. This paper introduces a new series stack topology, where the voltage unbalances are reduced. This in turn, mitigates the switching losses. The proposed topology consists of a circuit that ensures the soft switching of each device, and one auxiliary circuit that allows for switching energy recovery. The principle for the topology operation is presented and experimental tests are performed for two modules. The topology performs excellently for switching transients on each of the devices. The voltage static unbalances were limited to 10%, while the activation/deactivation delay introduced by the lower module IGBT driver takes place in the dynamic unbalances. Thus, the switching losses are reduced by 40%, when compared to hard switching configurations.

Thallium poisoning: a case report

  • Oscar Jimenez;Hector Caceres;Luis Gimenez;Luciana Soto;Micaela Montenegro;Jhon Alexander Avila Rueda
    • Journal of Yeungnam Medical Science
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    • v.40 no.3
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    • pp.311-314
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    • 2023
  • Thallium poisoning is usually accidental. We present a case of a 51-year-old woman who was evaluated in June 2018 for myalgia, vertigo, asthenia, and abdominal pain. Physical examination revealed temporal-spatial disorientation, jaundice, and asterixis. The laboratory reported the following: bilirubin, 10.3 mg/dL; aspartate transaminase, 78 U/L; alanine transaminase, 194 U/L; albumin, 2.3 g/dL; prothrombin time, 40%; and platelet count, 60,000/mm3. Serology performed for hepatitis A, B, and C; Epstein-Barr virus; cytomegalovirus; and human immunodeficiency virus was negative, and a collagenogram was negative. Physical reevaluation revealed alopecia on the scalp, armpits, and eyebrows; macules on the face; plantar hyperkeratosis; and ulcers on the lower limbs. Tests for lead, arsenic, copper, and mercury were carried out, which were normal; however, elevated urinary thallium (540 ㎍/g; range, 0.4-10 ㎍/g) was observed. The patient was treated with D-penicillamine 1,000 mg/day and recovered her urinary thallium levels were within normal range at annual follow-up. Thallium poisoning is extremely rare and can be fatal in small doses. An adequate clinical approach can facilitate early diagnosis.

Intake and performance of lambs finished in feedlot with wet brewer's grains

  • Frasson, Monica Feksa;Carvalho, Sergio;Jaurena, Gustavo;Menegon, Aliei Maria;Severo, Marcelo Machado;da Motta, Juliano Henriques;Teixeira, William Soares
    • Journal of Animal Science and Technology
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    • v.60 no.5
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    • pp.12.1-12.5
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    • 2018
  • Background: The use of agroindustrial by-products in ruminant nutrition to be an interesting alternative in order to reduce production costs and environmental impacts arising from the inadequate destination of residues. The initial step of beer production yields a large volume of wet brewer's grains all year around, which is available at a low cost and has a high nutritional quality, and hence a big potential for animal production. Methods: Twenty-four Suffolk non-castrated male lambs, from simple parturition were kept in individual spots and allocated to four treatments constituted by four levels of substitution of sorghum silage by WBG (i.e.0; 33.5; 66.5 and 100% of substitution). It was used roughage: concentrate rate of 50:50, based on dry matter. Results: The ether extract intake increased while the acid detergent fiber intake decreased linearly ($P{\leq}0.05$). Substituion of sorghum silage by WBG did not change lambs' feed DMI, daily weight gain and feed conversion. Conclusion: The substitution of sorghum silage by WBG as roughage showed to be a viable alternative from the productive and economic point of view for finishing of feedlot lambs.

Early Life Factors Influencing the Risk of Obesity

  • Lifschitz, Carlos
    • Pediatric Gastroenterology, Hepatology & Nutrition
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    • v.18 no.4
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    • pp.217-223
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    • 2015
  • The obesity epidemic is a worldwide problem. Factors predisposing to obesity include genetics, race, socioeconomic conditions, birth by cesarean section, and perinatal antibiotic use. High protein (HP) content in infant formulas has been identified as a potential culprit predisposing to rapid weight gain in the first few months of life and leading to later obesity. In a large multicountry study the effects of lower protein (LP) formula (1.77 and 2.2 g protein/100 kcal, before and after the 5th month, respectively) were compared to those of higher protein (2.9 and 4.4 g protein/100 kcal, respectively). Results indicated that at 24 months, the weight-for-length z score of infants in the LP formula group was 0.20 (0.06, 0.34) lower than that of the HP group and was similar to that of the breastfed reference group. The authors concluded that a HP content of infant formula is associated with higher weight in the first 2 years of life but has no effect on length. LP intake in infancy might diminish the later risk of overweight and obesity. At 6 years of age HP children had a significantly higher body mass index (by 0.51; 95% confidence interval [CI], 0.13-0.90; p=0.009) and a 2.43 (95% CI, 1.12-5.27; p=0.024) fold greater risk of becoming obese than those who received the LP. In conclusion, several factors may influence development of metabolic syndrome and obesity. Breastfeeding should always be encouraged. An overall reduction of protein intake in formula non breastfed infants seems to be an additional way to prevent obesity.

Study of the Production of Alkaline Keratinases in Submerged Cultures as an Alternative for Solid Waste Treatment Generated in Leather Technology

  • Cavello, Ivana A.;Chesini, Mariana;Hours, Roque A.;Cavalitto, Sebastian F.
    • Journal of Microbiology and Biotechnology
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    • v.23 no.7
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    • pp.1004-1014
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    • 2013
  • Six nonpathogenic fungal strains isolated from alkaline soils of Buenos Aires Province, Argentina (Acremonium murorum, Aspergillus sidowii, Cladosporium cladosporoides, Neurospora tetrasperma, Purpureocillium lilacinum (formerly Paecilomyces lilacinus), and Westerdikella dispersa) were tested for their ability to produce keratinolytic enzymes. Strains were grown on feather meal agar as well as in solid-state and submerged cultures, using a basal mineral medium and "hair waste" as sole sources of carbon and nitrogen. All the tested fungi grew on feather meal agar, but only three of them were capable of hydrolyzing keratin, producing clear zones. Among these strains, P. lilacinum produced the highest proteolytic and keratinolytic activities, both in solid-state and submerged fermentations. The medium composition and culture conditions for the keratinases production by P. lilacinum were optimized. Addition of glucose (5 g/l) and yeast extract (2.23 g/l) to the basal hair medium increased keratinases production. The optimum temperature and initial pH for the enzyme production were $28^{\circ}C$ and 6.0, respectively. A beneficial effect was observed when the original concentration of four metal ions, present in the basal mineral medium, was reduced up to 1:10. The maximum yield of the enzyme was 15.96 $U_c/ml$ in the optimal hair medium; this value was about 6.5-fold higher than the yield in the basal hair medium. These results suggest that keratinases from P. lilacinum can be useful for biotechnological purposes such as biodegradation (or bioconversion) of hair waste, leading to a reduction of the environmental pollution caused by leather technology with the concomitant production of proteolytic enzymes and protein hydrolyzates.

Removal of textile dyes in wastewater using polyelectrolytes containing tetrazole groups

  • Caldera-Villalobos, Martin;Pelaez-Cid, Alejandra-Alicia;Martins-Alho, Miriam-Amelia;Herrera-Gonzalez, Ana-Maria
    • Korean Journal of Chemical Engineering
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    • v.35 no.12
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    • pp.2394-2402
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    • 2018
  • Textile dyes are some of the pollutants which have received the most attention because of the large volume of wastewater generated by the textile industry. Removal by means of adsorption is one of the most versatile alternatives to treat these effluents. Even though different adsorbents such as activated carbons and mineral materials have been proposed, polymeric adsorbents are a viable alternative. This work reports for the first time the use of polyelectrolyte PTZ and macroelectrolyte MTZ containing tetrazole groups as adsorbents useful in the textile dyes removal present in aqueous solutions and wastewater. Because of the anionic character of the tetrazole group, MTZ exhibits selective adsorption capabilities for cationic dyes of up to $156.25mg{\cdot}g^{-1}$. The kinetic study of the process of adsorption shows that PTZ and MTZ fit a pseudo second-order model. MTZ also shows utility as a flocculant agent in the treatment of wastewater containing dyes Indigo Blue and Reactive Black. The results showed that PTZ and MTZ may be used in the treatment of wastewater in a process of coagulation-flocculation followed by the treatment by adsorption. This two-stage treatment removed up to 95% of the dye present in the wastewater. As well as removing the dyes, the values for COD, suspended solids, pH, and color of the wastewater decreased, thus significantly improving its quality.

Analysis of the transcripts encoding for antigenic proteins of bovine gammaherpesvirus 4

  • Romeo, Florencia;Spetter, Maximiliano J.;Moran, Pedro;Pereyra, Susana;Odeon, Anselmo;Perez, Sandra E.;Verna, Andrea E.
    • Journal of Veterinary Science
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    • v.21 no.1
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    • pp.5.1-5.12
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    • 2020
  • The major glycoproteins of bovine gammaherpesvirus 4 (BoHV-4) are gB, gH, gM, gL, and gp180 with gB, gH, and gp180 being the most glycosylated. These glycoproteins participate in cell binding while some act as neutralization targets. Glycosylation of these envelope proteins may be involved in virion protection against neutralization by antibodies. In infected cattle, BoHV-4 induces an immune response characterized by low neutralizing antibody levels or an absence of such antibodies. Therefore, virus seroneutralization in vitro cannot always be easily demonstrated. The aim of this study was to evaluate the neutralizing capacity of 2 Argentine BoHV-4 strains and to associate those findings with the gene expression profiles of the major envelope glycoproteins. Expression of genes coding for the envelope glycoproteins occurred earlier in cells infected with isolate 10/154 than in cells infected with strain 07/435, demonstrating a distinct difference between the strains. Differences in serological response can be attributed to differences in the expression of antigenic proteins or to post-translational modifications that mask neutralizing epitopes. Strain 07/435 induced significantly high titers of neutralizing antibodies in several animal species in addition to bovines. The most relevant serological differences were observed in adult animals. This is the first comprehensive analysis of the expression kinetics of genes coding for BoHV-4 glycoproteins in 2 Argentine strains (genotypes 1 and 2). The results further elucidate the BoHV-4 life cycle and may also help determine the genetic variability of the strains circulating in Argentina.

Maxillary sinus volumetric changes in jet aircraft pilots: A multislice computed tomography pilot study

  • Yeda da Silva;Luciana Munhoz;Jose Rodrigues Parga Filho;Andreza Gomes Damasceno;Cesar Felipe Franca da Rosa;Eduardo Bilaqui Zukovski;Erik Zhu Teng;Claudio Campi de Castro
    • Imaging Science in Dentistry
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    • v.53 no.1
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    • pp.53-60
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    • 2023
  • Purpose: This study evaluated maxillary sinus volume changes in military jet aircraft pilot candidates before and after the training program, in comparison with a control group, considering the effects of pressurization, altitude, and total flight hours, through multislice computed tomography. Materials and Methods: Fifteen fighter pilots were evaluated before initiating the training program and after the final approval. The control group consisted of 41 young adults who had not flown during their military career. The volumes of each maxillary sinus were measured individually before and at the end of the training program. Results: When comparing the initial and final volumes in the pilots, a statistically significant increase was observed both in the left and right maxillary sinuses. When evaluating the average total volume of the maxillary sinuses(i.e., the average volume of the right and left maxillary sinuses together), a significant increase in the volume of the maxillary sinuses was observed in the pilot group when compared to the control group. Conclusion: The maxillary sinus volumes in aircraft pilot candidates increased after the 8-month training program. This may be explained by changes in the gravitational force, the expansion of gas, and positive pressure from oxygen masks. This unprecedented investigation among pilots might lead to other investigations considering paranasal sinus alterations in this singular population.