Artificial sweeteners are food additives widely used, mainly in reduced sugar or sugar-free foods and beverages. Acesulfame potassium (ACE-K) and sodium saccharin (SAC) are among the most widely consumed sweeteners worldwide. These compounds when ingested are not metabolized by the body, being excreted unchanged. They arrive at treatment plants, where they are partially degraded and consequently released directly into water bodies. For this reason, artificial sweeteners have been detected in the most diverse aquatic environments, being recognized as emerging contaminants. In this work, aqueous solutions of ACE-K and SAC, submitted to heterogeneous photocatalysis (TiO2/UV-A) for 60 min, showed degradations of more than 99% and maximum mineralization of 57% for ACE-K and 49% for SAC. The effects of certain variables were evaluated, with pH having a greater influence on the degradation of acesulfame and the mass of semiconductor on that of saccharin. The degradation of ACE-K and SAC followed a pseudo-first-order kinetic model according to the Langmuir–Hinshelwood model. Assays using Artemia salina as the test organism demonstrated the low toxicity of the photocatalyzed solutions of ACE-K and SAC. The contribution of different reactive species to the photocatalysis was investigated using specific radical inhibitors; the results indicate that singlet oxygen (1O2) has a fundamental role in the photocatalytic degradation of ACE-K and SAC.
Since the myrtle rust pathogen (Austropuccinia psidii) was first reported (as Puccinia psidii) in Brazil on guava (Psidium guajava) in 1884, it has been found infecting diverse myrtaceous species. Because A. psidii has recently spread rapidly worldwide with an extensive host range, genetic and genotypic diversities were evaluated within and among A. psidii populations in its putative native range and other areas of myrtle rust emergence in the Americas and Hawaii. Microsatellite markers revealed several unique multilocus genotypes (MLGs), which grouped isolates into nine distinct genetic clusters [C1–C9 comprising C1: from diverse hosts from Costa Rica, Jamaica, Mexico, Puerto Rico, and USA‐Hawaii, and USA‐California; C2: from eucalypts (Eucalyptus spp.) in Brazil/Uruguay and rose apple (Syzygium jambos) in Brazil; C3: from eucalypts in Brazil; C4: from diverse hosts in USA‐Florida; C5: from Java plum (Syzygium cumini) in Brazil; C6: from guava and Brazilian guava (Psidium guineense) in Brazil; C7: from pitanga (Eugenia uniflora) in Brazil; C8: from allspice (Pimenta dioica) in Jamaica and sweet flower (Myrrhinium atropurpureum) in Uruguay; C9: from jabuticaba (Myrciaria cauliflora) in Brazil]. The C1 cluster, which included a single MLG infecting diverse host in many geographic regions, and the closely related C4 cluster are considered as a “Pandemic biotype,” associated with myrtle rust emergence in Central America, the Caribbean, USA‐Florida, USA‐Hawaii, Australia, China‐Hainan, New Caledonia, Indonesia and Colombia. Based on 19 bioclimatic variables and documented occurrences of A. psidii contrasted with reduced sets of specific genetic clusters (subnetworks, considered as biotypes), maximum entropy bioclimatic modelling was used to predict geographic locations with suitable climate for A. psidii which are at risk from invasion. The genetic diversity of A. psidii throughout the Americas and Hawaii demonstrates the importance of recognizing biotypes when assessing the invasive threats posed by A. psidii around the globe. 相似文献
Bacterial leaf blight of eucalypt, caused by Xanthomonas axonopodis, occurs mainly in forest nurseries, but also affects young plants in the field. Avoidance of leaf wetness for long periods of time over the whole nursery and using drip irrigation for clonal hedges are, currently, the most effective measures for controlling bacterial leaf blight on eucalypt. However, as these techniques are very costly, alternative management measures are required. We hypothesized that the management of mineral nutrients could reduce disease severity on eucalypts. To examine this hypothesis, rooted cuttings of Eucalyptus urophylla × E. grandis were irrigated with nutrient solutions containing different concentrations of copper (Cu), boron (Bo), potassium (K), calcium (Ca) and nitrogen (N) before inoculation with X. axonopodis 30 days after starting the nutrient solution treatments. Concentration of K higher than that recommended, commonly used in miniclonal hedges, reduced the severity of bacterial leaf blight. However, disease severity increased with an increasing of N/K ratio. The management of mineral nutrition solution, especially K, has great potential for integrated disease management of X. axonopodis in eucalypt nurseries. 相似文献
The sprawl of the urbanization and road network process without building ecological corridors contributes to the high mortality rates and a threat to the population decline of wild species such as the crab‐eating fox. A strategy for the ex situ conservation is the study of the reproductive biology of the species and cryopreservation of their genetic heritage through the formation of an animal germplasm bank. This research is in accordance with the principles adopted by Brazilian College of Animal Experimentation. Reproductive systems of Cerdocyon thous females (n = 7) were examined macroscopically and microscopically by histological techniques and scanning electron microscopy. Gross features showed the shape of the ovaries was similar to a bean, and the elongated oviducts lengths were between 5 and 8 cm, with body of the uterus (3 cm) with long and narrow uterine horns (9–11 cm). The cervix was as a single annular conformation carrying out communication between the uterus and the vagina. The vagina has lengthened and circular muscle and the vulva with dense anatomical conformation with a quite pronounced clitoris. In addition, with regard to the establishment of a cell line (fibroblasts) for the gene bank enrichment, cells showed a low clonogenic capacity, especially when compared to domestic dogs, which can be explained by “in vitro” environment, age and diet of the animal. However, it was possible to create a bank of limited cell number. This study had morphological and preservationist character and aimed to help at long term in the conservation of wild animal's genetic resources. 相似文献
The wood panel industry uses a large volume of wood and it is essential to research the use of new tree species for these types of products. As such, the aim of this study was to evaluate the feasibility of Cordia trichotoma (Vell.) wood, both on its own and as a mixture with Pinus spp., as well as to understand the effect on particleboard quality when adding the species’ bark and shavings. The experimental design included nine treatments that assessed various mixture proportations of C. trichotoma and Pinus; for example, 10% bark, and 10% shavings of C. trichotoma with Pinus spp. and C. trichotoma particles, as well as mixtures of these two species in proportions of 25/75%, 50%/50%, and 75/25%. The results indicate that the Cordia trichotoma specie is technically feasible when manufacturing particleboards in pure form. The incorporation of bark (at 10% of the mixture) is also technically feasible. It is also feasible to use the shavings of C. trichotoma. In general, all treatments produced outputs that showed dimensional stability and mechanical strength statistically equal or higher than control treatments (Pinus spp.); thus, these products may be used for non-structural applications in dry and/or moist conditions. 相似文献
A 7‐year‐old intact male Boxer was referred to our services at the Veterinary Teaching Hospital of the University of Trás‐os‐Montes and Alto Douro, suffering from a persistently erect penis (including the bulbus glandis) that had been exposed for several days. Radiographic and ultrasonographic examinations detected a 5.0 × 3.5 cm mass located dorso‐laterally to the urinary bladder. The microbial culture of the mass revealed Staphylococcus spp. At that time, we suspected the involvement of an abscess in the origin of the priapism. Medical and surgical treatments were promptly instituted, which allowed for penile withdrawal into the prepuce; however, the resolution of the penile erection was not accomplished in the following days and penile amputation was required. Histological evaluation of the excised penis revealed extensive infarction of the erectile tissue of the pars longa and bulbus glandis, and also of the blood vessels of the penis. Following penile amputation and antimicrobial therapy, the animal fully recovered. Ultimately, the animal died as a consequence of gastric torsion. At necropsy, some lesions compatible with a previous perforation of the intestinal wall were recorded. The data gathered from the anamnesis, the physical and imaging examinations, along with the post‐mortem findings, allowed us to conclude that in this clinical case the primary cause of priapism was a perineal abscess due to bowel perforation. 相似文献
The Bm86 antigen has been used to control ticks of the Boophilus genera in integrated programs that also include the use of acaricides. Because of recent phylogenetic studies have lead to the inclusion of all Boophilus species within the Rhipicephalus genera, we aimed to investigate the efficacy of the Bm86 antigen on the biotic potential of Rhipicephalus sanguineus. Domestic dogs were vaccinated with Bm86 and challenged with the three instars of R. sanguineus. Male and female mongrel dogs were divided into two groups of four animals each, comprising non-vaccinated and vaccinated animals. Immunized dogs were given two doses of an experimental formulation containing 50 μg of recombinant Bm86, at 21 days interval while the other group was given placebo, consisting of the same preparation without Bm86. Each dog was challenged 21 days after the last dose with 250 larvae, 100 nymphs and 55 adults (25 females and 30 males) released inside feeding chambers (one per instar) glued to their shaved flank. The effect of the vaccination was evaluated by determining biological parameters of ticks including the yield rates of larvae, nymphs and adult females. Adult females engorged weight, egg mass weight, efficiency rate of conversion to eggs (ERCE) and hatchability. In addition, sera were collected from dogs at 0, 21, 36, 45 and 75 days after the vaccination and used for the detection of specific antibodies by ELISA. Collection rates of larvae, nymphs and adult females fed on vaccinated dogs were significantly (p < 0.05) reduced by 38%, 29% and 31%, respectively, as compared with non-vaccinated controls. Significant reductions were also observed in weight of engorged females and egg mass, in ERCE, but not in the hatch rate of ticks fed on immunized dogs. ELISA data revealed a marked and significant increase in optical densities of sera from vaccinated animals after the second dose of Bm86. We concluded that the Bm86 antigen used as a vaccine for dogs reduced the viability and biotic potential of the R. sanguineus. 相似文献
Growth performance was evaluated in juvenile pacu (Piaractus mesopotamicus) and dourado (Salminus brasiliensis) fed diets containing 0%, 10% and 20% of lyophilized bovine colostrum for 60 days. The performance variables of weight gain, relative weight gain, feed intake, feed conversion ratio, specific growth rate, total protein intake and protein efficiency ratio were evaluated as well as apparent digestibility coefficients of protein and energy in the diets. Inclusion of bovine colostrum did not induce differences in the performance of pacu and dourado (P > 0.05), indicating that the diets were adequate and met the nutritional needs of the juveniles. The protein digestibility in both species was improved with the inclusion of the bovine lacteal secretion. Based on the variables studied, the diets with lyophilized bovine colostrum inclusion were nutritionally suitable for both pacu and dourado indicating the possibility to use this lacteal secretion as a partial substitute of dietary protein. 相似文献
An 18‐year‐old Quarter Horse mare presented with an 18 week history of dermatological lesions characterised by recurrent urticaria and recent signs of enlarged mammary glands, pyrexia, alopecia and intense pruritus. Haematological and serum biochemical analyses revealed anaemia, leucocytosis, thrombocytopenia and hyperfibrinogenaemia. Mammary discharge was evaluated and revealed neutrophilia. Cytological examinations of fine needle aspirates from the parotid lymph nodes were normal. Common causes of anaemia were ruled out by specific tests. The initial diagnosis was mastitis and 2 weeks later the animal returned to the hospital with worsening of clinical signs, intermittent fever, intense pruritus and generalised alopecia. Blood samples were collected for haematological and serum biochemical analyses, and the mammary gland and parotid lymph nodes were biopsied. Rectal palpation revealed a large irregular mass near the left kidney with adhesions of surrounding structures. The animal died before the laboratory results were ready. This report details the clinical, histological and immunophenotypic findings of a case of large lymphoma in a mare. 相似文献
Visceral leishmaniasis is a disease caused by Leishmania (Leishmania) chagasi and represents a serious public health problem. The dog is the main urban reservoir of the disease; however, investigations regarding the occurrence and epidemiological importance of leishmaniasis in cats have recently been initiated. This study aimed to detect cats seropositive for Leishmania spp. using different antigens. Additional studies were performed using sera from cats with Toxoplasma gondii (n=15) to evaluate cross-reactivity. Serum samples (n=113) from cats living in the town of Ara?atuba, State of S?o Paulo, Brazil, an endemic area for human and canine visceral leishmaniasis, were tested by indirect ELISA using different antigens: crude (CAG-ELISA), fucose-mannose ligand (FML-ELISA) and K39 (rK39-ELISA). Anti-Leishmania spp. antibodies were detected in 23.0% of samples evaluated by CAG-ELISA, 13.3% by FML-ELISA and 15.9% by RK39-ELISA. Only reactive sera in all three tests were considered truly positive. No disagreement occurred among the tests (p<0.05). Serum samples seropositive for toxoplasmosis tested by CAG-ELISA were negative, but one sample (6.7%) was positive for FML-ELISA and rK39-ELISA suggesting a cross-reaction between these antigens and anti-T. gondii antibodies. These findings indicate the occurrence of feline leishmaniasis in Ara?atuba. Further studies are required to clarify the role of cats in the epidemiological cycle of leishmaniasis. 相似文献
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