RESUMO
Inappropriate diets cause many of the health problems commonly reported in parrots by psittaculturists and veterinarians. The dietary management of captive parrots would benefit from information derived from studies of dietary habits of wild parrots; however, it is unclear how complete this body of knowledge is at this time. Documentation of parrots' dietary habits appears to have grown dramatically over the past century. Reports of parrots consuming a number of foodstuffs beyond the reproductive parts of plants (alternate foodstuffs) have increased. The extent of alternate foodstuffs in parrot diets is currently unknown. We used Google search engines (ie, Scholar, Videos, Images) to determine how well psittaciform dietary habits have been studied to date and to quantify reports of alternate foodstuffs consumption among genera of Psittaciformes. We found that the dietary habits of over 43% of parrot species are poorly resolved. The dietary habits of 71.5% of parrot species classified by the International Union for Conservation of Nature as at risk of extinction are not well resolved. Parrots' consumption of alternate foodstuffs occurred at the following rates at the genus level: 91.2% foliage, 76.9% terrestrial invertebrates and fine earthen materials, 74.7% wood, 44% pure minerals, 34.1% vertebrates (9.9% dung), 29.7% sap, 19.8% roots, 17.6% charcoal, 18.7% epiphytes, 16.5% coarse earthen materials, 8.8% algae, and 6.6% aquatic invertebrates. Of these reports, 79.1% involved observations of wild parrots. Many parrot species may be more omnivorous than previously realized. Alternate foodstuffs are generally absent from current veterinary-based dietary recommendations for captive parrots. Future studies are needed to determine whether providing alternate foodstuffs to captive parrots can be used as a means to improve their diets and thus their health, welfare, and reproductive success.
Assuntos
Dieta , Papagaios , Animais , Dieta/veterináriaRESUMO
Psittacidae is one of the most endangered families of birds in the world. Knowledge of their nutrition is important for understanding their survival and productivity in the wild, as well as for their adequate husbandry under human care. Hand-rearing is a common practice for psittacines, however research on their nutrition is limited. We analysed the predicted metabolisable energy, crude protein, crude fat, minerals and the essential amino acid profiles of the crop contents from free-living nestlings of scarlet macaws (Ara macao) and red-and-green macaws (Ara chloropterus) from southeastern Peru, Cuban Amazons (Amazona leucocephala bahamensis) from the Bahamas, lilac-crowned Amazons (Amazona finschi) from northwestern Mexico and thick-billed parrots (Rhynchopsitta pachyrhyncha) from northern Mexico. The crop content of the different parrot species displayed remarkably similar nutritional profiles, considering their diversity in habitats, geographic ranges and food sources. The crude protein and crude fat concentrations in crop samples were particularly similar for the Ara and Amazona species, while the thick-billed parrot stood out for its higher crude fat and lower crude protein content. Wider variations were found among the concentrations of sodium (Na) and iron (Fe), proline and tryptophan. Compared with the requirements of 6-12 weeks leghorn chickens, all free-ranging parrot diets contained lower crude protein, calcium (Ca), potassium (P) and Na concentrations. The hand-feeding formulas contained lower crude fat, magnesium (Mg), arginine, valine and phenylalanine concentrations, as well as much higher levels of Ca and zinc (Zn), in comparison with parrot crop samples. Our data suggest that a single formulation could be used to hand-rear Ara and Amazona sp. of 3 weeks of age and older, while a different formulation would likely be more appropriated for Rhynchopsitta sp. Experimental studies should evaluate if increasing the concentration of crude fat, Mg, arginine, valine and phenylalanine enhances psittacine chick growth and health.
Assuntos
Amazona , Papagaios , Psittaciformes , Animais , Arginina , Galinhas , Humanos , Magnésio , Fenilalanina , Sódio , ValinaRESUMO
BACKGROUND: An electrical potential not previously reported-electrical cochlear response (ECR)-observed only in implanted patients is described. Its amplitude and growth slope are a measurement of the stimulation achieved by a tone pip on the auditory nerve. The stimulation and recording system constructed for this purpose, the features of this potential obtained in a group of 43 children, and its possible clinical use are described. The ECR is obtained by averaging the EEG epochs acquired each time the cochlear implant (CI) processes a tone pip of known frequency and intensity when the patient is sleeping and using the CI in everyday mode. The ECR is sensitive to tone pip intensity level, microphone sensitivity, sound processor gain, dynamic range of electrical current, and responsiveness to electrical current of the auditory nerve portion involved with the electrode under test. It allows individual evaluation of intracochlear electrodes by choosing, one at the time, the central frequency of the electrode as the test tone pip frequency, so the ECR measurement due to a variable intensity tone pip allows to establish the suitability of the dynamic range of the electrode current. RESULTS: There is a difference in ECR measurements when patients are grouped based on their auditory behavior. The ECR slope and amplitude for the Sensitive group is 0.2 µV/dBHL and 10 µV at 50 dBHL compared with 0.04 µV/dBHL and 3 µV at 50dBHL for the Inconsistent group. The clinical cases show that adjusting the dynamic range of current based on the ECR improved the patient's auditory behavior. CONCLUSIONS: ECR can be recorded regardless of the artifact due to the electromyographic activity of the patient and the functioning of the CI. Its amplitude and growth slope versus the intensity of the stimulus differs between electrodes. The relationship between minimum ECR detection intensity level and auditory threshold suggests the possibility of estimating patient auditory thresholds this way. ECR does not depend on the subject's age, cooperation, or health status. It can be obtained at any time after implant surgery and the test procedure is the same regardless of device manufacturer.
Assuntos
Limiar Auditivo/fisiologia , Implantes Cocleares , Criança , Nervo Coclear/fisiologia , Potenciais Evocados Auditivos , Feminino , Humanos , MasculinoRESUMO
Research on psittacine nutrition is limited, and nestling requirements are poorly understood. This study analysed fatty acid (FA) profiles of crop contents of free-living scarlet macaws (Ara macao, n = 18), red-and-green macaws (Ara chloropterus, n = 5), Cuban parrots (Amazona leucocephala bahamensis, n = 27), lilac-crowned Amazons (Amazona finschi, n = 33) and thick-billed parrots (Rhynchopsitta pachyrhyncha, n = 32). The same analysis was carried out on 15 commercial parrot hand-feeding formulas. The mean FA concentration of the crop samples of each species ranged from 15% to 53% DM for crop samples and ranged from 6% to 22% for hand-feeding formulas. Long-chain FA represented over 92% of all FA in the crop samples and over 81% of all FA in the commercial formulas. Parrot species shared similarities in saturation profiles of crop samples, ranging between 13%-29% saturated fatty acids (SFA), 12%-40% monounsaturated fatty acids (MUFA) and 39%-58% polyunsaturated fatty acids (PUFA). All studied psittacines, except for the red-and-green macaw, were within the range of values for hand-rearing formulas. Palmitic acid was the most common SFA in scarlet macaws, red-and-green macaws, Cuban parrot, thick-billed parrot and in all but one commercial formula. Palmitic and stearic acids dominated the SFA in the samples of the Lilac-crowned Amazon. Oleic acid was the most common MUFA in all hand-feeding formulas as well as in the crop samples, except for the lilac-crowned amazon and the thick-billed parrot where vaccenic acid dominated. Linoleic acid was by far the most common PUFA found in the crop samples as well as in the hand-feeding formulas. PUFA were largely dominated by the n6 family, both in the crop samples and the formulas. The data presented on nestling diets of free-living parrot species provide a foundation for future researchers to test whether increasing FA concentration in hand-feeding formulas improves nestling development or if species-specific formulas will be advantageous.
Assuntos
Ácidos Graxos , Papagaios , Animais , Dieta/veterinária , Ácidos Graxos Monoinsaturados , Ácidos Graxos InsaturadosRESUMO
If Septic shock (SS) evolves to refractory SS, mortality could reach 90%, despite giving an optimal treatment. Nowadays, extracorporeal devices which adsorb inflammatory cytokines are available, reducing the systemic inflammatory response syndrome. These devices can be used with continuous renal replacement therapy or conventional hemodialysis. We report two diabetic females aged 50 and 58 years, who underwent a total colectomy and amputation of diabetic foot and who developed a SS with high requirements of vasoactive drugs (norepinephrine and adrenaline) to maintain a mean arterial pressure about 60 mmHg. Both were subjected to hemodialysis, connected to a cytokine hemadsorption device. The most important finding was the progressive reduction of vasopressor doses, effect that was observed nine hours after the beginning of the hemadsorption and lasted until its removal at 26 hours. Both patients survived.
Assuntos
Citocinas/sangue , Hemoperfusão/instrumentação , Hemoperfusão/métodos , Diálise Renal/instrumentação , Diálise Renal/métodos , Choque Séptico/terapia , Feminino , Humanos , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Fatores de Tempo , Resultado do TratamentoRESUMO
Many pollutants released into the environment as a result of human activities are chiral. Pollution control strategies generally consider chiral compounds as if they were achiral and rarely consider enantiomers separately. We compared the performance of three different materials, an organically-modified anionic clay (HT-ELA) and two organic agro-food residues (ALP and ALPc), as amendments to immobilize the chiral fungicide metalaxyl in two soils with different textures, addressing the effects of the amendments on the sorption, persistence, and leaching of each of the two enantiomers of metalaxyl (R-metalaxyl and S-metalaxyl) separately. The effects of the amendments were both soil- and amendment-dependent, as well as enantiomer-selective. The organo-clay (HT-ELA) was much more efficient in increasing the sorption capacity of the soils for the two enantiomers of metalaxyl than the agro-food residues (ALP and ALPc), even when applied at a reduced application rate. The enhanced sorption in HT-ELA-amended soils reduced the bioavailability of metalaxyl enantiomers and their leaching in the soils, mitigating the particularly high leaching potential of the more persistent S enantiomer. The immobilizing capacity of the agro-food residues was more variable, mainly because their addition did not greatly ameliorate the sorption capacity of the soils and had variable effects on the enantiomers degradation rates. HT-ELA showed potential to reduce the bioavailability and mobility of metalaxyl enantiomers in soil and to mitigate the contamination problems particularly associated with the higher leaching potential of the more persistent enantiomer.
Assuntos
Alanina/análogos & derivados , Recuperação e Remediação Ambiental/métodos , Fungicidas Industriais/química , Hidróxidos/química , Poluentes do Solo/química , Solo/química , Alanina/análise , Alanina/química , Silicatos de Alumínio/química , Argila , Fungicidas Industriais/análise , Humanos , Poluentes do Solo/análise , EstereoisomerismoRESUMO
The horned guan (Oreophasis derbianus) is an endangered species with small and seriously fragmented wild populations. Breeding efforts during the last decade have maintained a slowly increasing captive population with the potential to play an important role in the recovery of the species. Clinical hematology and biochemistries are powerful tools to diagnose and monitor diseases in captive birds. Therefore, establishing hematologic and plasma biochemistry reference values will improve the medical management of this species. This study determines the reference values for 9 hematologic and 15 plasma biochemical variables for 27 male and 12 female, apparently healthy, captive horned guans from three institutions. Differences related to age, sex, and husbandry were identified but were usually small and clinically insignificant. These results should improve veterinary care of captive individuals of this species and provide comparative data for other species of cracids.
Assuntos
Aves/sangue , Aves/classificação , Animais , Animais de Zoológico/sangue , Análise Química do Sangue/veterinária , Espécies em Perigo de Extinção , Feminino , Masculino , Valores de Referência , Especificidade da EspécieRESUMO
Introduction: The prognostic ability of myocardial injury across different waves of the COVID-19 pandemic is not well established. The purpose of this study was to evaluate the prevalence and prognostic implications of myocardial injury in the first and sixth wave of COVID-19. Methods: We conducted a retrospective observational study that included patients admitted to the emergency department with COVID-19 with data on concentrations of cardiac troponin during the first and sixth wave. We compared the prevalence of myocardial injury and its predictive capacity for 30-day all-cause death in both waves. Results and discussion: A total of 346 patients were included (1st wave 199 and 6th wave 147 patients). The prevalence of myocardial injury was 21% with non-significant differences between waves. Myocardial injury was associated, in both waves, with a higher prevalence of comorbidities and with an increased risk of 30-day all-cause death [1st wave HR: 3.73 (1.84-7.55); p < 0.001 and 6th wave HR: 3.13 (1.23-7.92); p = 0.016], with non-significant differences in predictive capacity between groups after ROC curve analysis [AUC: 1st wave 0.829 (95% CI: 0.764-0.895) and 6th wave 0.794 (95% CI: 0.711-0.876)]. As limitations, this is a retrospective study with a relatively small simple size and troponin assay was performed at the discretion of the emergency physician so selection bias could be present. In conclusion, the prevalence of myocardial injury and its prognostic capacity was similar in both waves despite vaccination programs. Myocardial injury predicts short-term mortality in all COVID-19 patients, so they should be treated intensively.
RESUMO
Certain soil management practices can affect the enantioselective behavior of chiral pesticide enantiomers in agricultural soils. In this work, laboratory experiments were conducted to study the effects of olive-mill waste (OMW) addition to a Mediterranean agricultural soil on the enantioselectivity of sorption, degradation, and leaching processes of the chiral fungicide metalaxyl. Sorption-desorption isotherms indicated that the sorption of metalaxyl enantiomers by unamended and OMW-amended soil (2% w/w) was non-enantioselective and that OMW addition had little effect on the extent of sorption of metalaxyl enantiomers by the soil. Soil incubation experiments revealed that the degradation of metalaxyl in unamended soil was highly enantioselective, with R-metalaxyl being degraded faster (t1/2 = 12 days) than S-metalaxyl (t1/2 = 39 days). OMW addition to the soil increased the half-life of the biologically-active R-metalaxyl enantiomer from 12 to 28 days, and decreased the half-life of the non-active S-metalaxyl enantiomer from 39 to 33 days. Consequently, the enantioselectivity of metalaxyl degradation in the soil was greatly reduced upon OMW addition. Column leaching data were consistent with batch sorption and incubation results, showing similar retardation of S- and R-metalaxyl in unamended and OMW-amended soil and enantioselective leaching of the fungicide only in unamended soil. The results have important implications regarding the biological efficacy and environmental impact of the fungicide when applied as a mixture of enantiomers or racemate to OMW-treated soils.
Assuntos
Alanina/análogos & derivados , Fertilizantes , Olea , Solo , Absorção , Agricultura , Alanina/química , Alanina/metabolismo , Biodegradação Ambiental , Meio Ambiente , Fungicidas Industriais/química , Fungicidas Industriais/metabolismo , Meia-Vida , Resíduos Industriais , Poluentes do Solo/química , Poluentes do Solo/metabolismo , Espanha , EstereoisomerismoRESUMO
There are many intersecting aspects to the avicultural management of a captive flock. Extensive knowledge of the natural history of the species kept is key to fulfilling the environmental, social, nutritional, and behavioral requirements of the birds, whether in a mixed- or sole-species aviary. Species compatibility with the environment, climate, and other co-occupants plays a role as well, as does hygiene, good avicultural management, and veterinary involvement and consultation. In understanding and meeting these requirements, optimal health can be maintained through the reduction or elimination of stressors and the maintenance of normal physiologic function.
Assuntos
Criação de Animais Domésticos , Bem-Estar do Animal , Doenças das Aves/prevenção & controle , Animais , AvesRESUMO
We conducted nutritional analyses of diets offered to and ingested by seven pairs of horned guans (Oreophasis derbianus) in three zoos. Digestibility was calculated with individually housed birds (n=1 at each zoo). Diets offered varied widely among institutions, both in ingredients fed as well as in nutrient composition. Feeding selectivity was evident through differences in composition of diets offered vs. consumed, with fruit (bananas, grape, and/or plantain) and avocado (when offered) highly preferred; green leaves, poultry pellets, and other vegetables comprised lesser proportions of the diet. All facilities fed 2-3X more food than consumed, allowing a great degree of choice of preferred items and potentially consumption of nutritionally imbalanced diets-in particular, mineral constituents. Diets were highly digestible; dry matter (DM) digestion coefficients ranged from 70 to approximately 90%; protein digestibility varied from 30 to 80%; fat was >90% digestible. Diet composition was compared with known nutritional requirements of domestic avian species, and feeding recommendations discussed. Despite the wide variability in nutrient composition of diets eaten (i.e. protein 6-10% of DM; fat 2-17% of DM), no overt health problems were noted and all pairs had successfully reproduced on these diets. It is suggested that horned guans may have nutrient requirements more similar to those suggested for other frugivorous birds than values determined for poultry as the physiologic model. Comparisons with native food items, as well as more detailed nutrient balance studies, may provide even better guidelines for captive management of this highly endangered species.
Assuntos
Animais de Zoológico/fisiologia , Galliformes/fisiologia , Fenômenos Fisiológicos da Nutrição Animal/fisiologia , Animais , Dieta , Digestão/fisiologia , Ingestão de Alimentos/fisiologia , Feminino , MasculinoRESUMO
BACKGROUND: Imazaquin is a chiral herbicide which displays high mobility in soils. Like other imidazolinones, imazaquin is available for use only as racemic mixture of its enantiomers. In this work, several clay materials were assayed as adsorbents of imazaquin, and then the most suitable material was selected to prepare a clay-based slow release imazaquin nanoformulation containing exclusively the biologically active R-enantiomer. Next, laboratory experiments were conducted to illustrate the benefits of using the clay-based R-imazaquin formulation over the free (non-supported) racemic herbicide or the free pure R-imazaquin enantiomer regarding its leaching behavior and bioefficacy. RESULTS: The clay material selected as a carrier for R-imazaquin, hexadecyltrimethylammonium-saturated montmorillonite (SA-HDTMA), combined a high affinity for the herbicide and a high stability of the clay-herbicide adsorption complex. In a simulated scenario of high water input shortly after herbicide application, the clay-based R-imazaquin formulation displayed reduced leaching and increased bioefficacy compared to free racemic imazaquin and free R-imazaquin. CONCLUSION: The new clay-R-imazaquin formulation prepared, besides avoiding the environmental impact caused by the application of the less active S-enantiomer, reduced the herbicide leaching losses and prolonged the herbicidal activity, by increasing the residence time of the herbicide in the topsoil. © 2018 Society of Chemical Industry.
Assuntos
Bentonita/química , Herbicidas/química , Imidazóis/química , Quinolinas/química , Brassica/efeitos dos fármacos , Argila/química , Compostos de Amônio Quaternário/química , Solo/química , Estereoisomerismo , Água/químicaRESUMO
Introduction: Primary health care clinicians play an important role in the management of depression. Thus, it is very important to have a valid and reliable assessment of the competences needed to manage depression in primary health care, with the use of clinical simulation providing such an opportunity. Objective: The present study describes the assessment of primary health care clinicians' depression-related skills through a series of objective structured clinical examination stations. Material and Methods: Clinicians from multi-professional teams for the management of depression at two primary health care clinics in Santiago, Chile, went through seven objective structured clinical examination stations, lasting 10 to 20 min each, to assess their depression-related skills. The clinical and communicative skills measured were in accordance with clinical guidelines. Standardized patients portrayed cases usually encountered in clinical practice, while expert raters evaluated clinicians' performance with standardized checklists. Results: Psychosocial clinicians performed better than biomedical clinicians in the assessed skills. The most notable results were as follows: a high level of accomplishment in the relationship with patient, medical anamnesis, health checkup, and lab test requests; heterogeneous performance in patient management according to screening results, feedback to the patient, and registration in clinical records; and major deficiencies in the differential diagnosis of bipolar disorder. Discussion: The objective structured clinical examinations administered provided an opportunity to perform an in-depth examination of the depression-related skills of primary health care clinicians, where flaws in the screening and diagnosis procedures used by biomedical clinicians were detected. Given the significant involvement of these types of clinicians in depression management, undergraduate-level and continuing health education opportunities are needed.
RESUMO
The aim of this work was to study the effect of the application of a solid waste from olive oil production (alperujo) on the movement and persistence of the herbicide terbuthylazine (N2-tert-butyl-6-chloro-N4-ethyl-1,3,5-triazine-2,4-diamine). An experimental olive grove was divided in two plots: (i) Plot without organic amendment (blank) and (ii) Plot treated with alperujo during 3 years at a rate of 17920 kg of alperujo ha(- 1). Terbuthylazine was applied to both plots at a rate of 2 kg ha(- 1) a.i. Triplicates from each plot were sampled at 3 depths (0-10, 10-20 and 20-30 cm), air-dried, remains of olive leaves, grass roots, and stones removed and sieved through a 5 mm mesh sieve. Terbuthylazine was extracted with methanol 1:2 weight:volume ratio, the extracts were evaporated to dryness, resuspended in 2 mL of methanol, filtered and anylized by high performance liquid chromatography (HPLC). Higher amounts of terbuthylazine were detected at each sampling depth in plots treated with alperujo. The increase in soil organic matter content upon amendment with alperujo slightly increased sorption, suggesting that other factors beside sorption affect terbuthylazine degradation rate in organic amended soils.
Assuntos
Herbicidas/análise , Resíduos Industriais/análise , Poluentes do Solo/análise , Triazinas/análise , Adsorção , Cromatografia Líquida de Alta Pressão , Azeite de Oliva , Óleos de Plantas , Fatores de TempoRESUMO
Ground and surface water contamination by herbicides applied to olive groves in Spain and other Mediterranean countries is demanding strategies to prevent and remediate the environmental problems repeatedly caused by such herbicides. In this study, six different organic cations (L-carnitine, spermine, hexadimethrine, tyramine, phenyltrimethylammonium, and hexadecyltrimethylammonium) were incorporated into Na-rich Wyoming montmorillonite (SWy-2) and Ca-rich Arizona montmorillonite (SAz-1) at two different loadings (50% and 100% of the cation exchange capacity of the clays) as a strategy to enhance the affinity of the clay minerals for three herbicides widely used in olive groves: terbuthylazine, diuron, and MCPA. The modified montmorillonites were characterized and tested as adsorbents of the herbicides through batch adsorption tests. At the experimental conditions used, some of the modified montmorillonites removed more than 95% of the herbicide initially present in aqueous solution, whereas the unmodified clays removed less than 15%. All three herbicides displayed very strong affinities for SAz-1 exchanged with hexadecyltrimethylammonium cations, particularly when these were incorporated at 100% of the cation exchange capacity of the clay mineral. Terbuthylazine and diuron also displayed very strong affinities for SWy-2 exchanged with L-carnitine and spermine, respectively. The chemical characteristics of the organic cation greatly influenced the adsorptive properties of the resultant organoclay. The herbicides were in general reversibly adsorbed by the modified clays. The results indicate that some of the tested modified clays could be suitable for the removal of the assayed herbicides from contaminated water and also as possible supports for the design of slow release formulations of such herbicides to attenuate their environmental impact when used in high-risk scenarios such as olive groves.
Assuntos
Agricultura/métodos , Silicatos de Alumínio/química , Herbicidas/química , Minerais/química , Olea/crescimento & desenvolvimento , Adsorção , Argila , Poluentes do Solo/química , Poluição Química da Água/prevenção & controleRESUMO
The addition of organic amendments to soil increases soil organic matter content and stimulates soil microbial activity. Thus, processes affecting herbicide fate in the soil should be affected. The objective of this work was to investigate the effect of olive oil production industry organic waste (alperujo) on soil sorption-desorption, degradation, and leaching of diuron [3-(3,4-dichlorophenyl)-1,1-dimethylurea] and terbuthylazine [N2-tert-butyl-6-chloro-N4-ethyl-1,3,5-triazine-2,4-diamine], two herbicides widely used in olive crops. The soils used in this study were a sandy soil and a silty clay soil from two different olive groves. The sandy soil was amended in the laboratory with fresh (uncomposted) alperujo at the rate of 10% w/w, and the silty clay soil was amended in the field with fresh alperujo at the rate of 256 kg per tree during 4 years and in the laboratory with fresh or composted alperujo. Sorption of both herbicides increased in laboratory-amended soils as compared to unamended or field-amended soils, and this process was less reversible in laboratory-amended soils, except for diuron in amended sandy soil. Addition of alperujo to soils increased half-lives of the herbicides in most of the soils. Diuron and terbuthylazine leached through unamended sandy soil, but no herbicide was detected in laboratory-amended soil. Diuron did not leach through amended or unamended silty clay soil, whereas small amounts of terbuthylazine were detected in leachates from unamended soil. Despite their higher sorption capacity, greater amounts of terbuthylazine were found in the leachates from amended silty clay soils. The amounts of dissolved organic matter from alperujo and the degree of humification can affect sorption, degradation, and leaching of these two classes of herbicides in soils. It appears that adding alperujo to soil would not have adverse impacts on the behavior of herbicides in olive production.
Assuntos
Diurona/análise , Óleos de Plantas/química , Solo/análise , Triazinas/análise , Eliminação de Resíduos Líquidos , Diurona/química , Manipulação de Alimentos , Herbicidas/análise , Luz , Azeite de Oliva , Triazinas/químicaRESUMO
A Mg/Al layered double hydroxide (LDH) was intercalated with the anionic herbicides 2,4-D, MCPA, and picloram by using three different methodologies: (i) direct synthesis (DS), (ii) regeneration (RE), and (iii) ion exchange (IE). The resulting complexes were characterized and assayed by batch release and column leaching tests, aiming at the controlled release of these herbicides. All the tested LDH-herbicide complexes displayed similar slow herbicide release properties in water, although the IE method seemed to result in complexes with a greater fraction of herbicide in a readily available form. Apparently, the LDH-herbicide complexes released most of the active ingredient present in the complexes at the end of the batch release experiment. This was attributed to the replacement of the intercalated herbicide by carbonate and hydroxyl anions from the aqueous solution. Compared to the free herbicides, the application of the three LDH-herbicide complexes (RE) to soil columns resulted in reduction in the maximum herbicide concentration in leachates and led to the retardation of herbicide leaching through the soil. All LDH-herbicide complexes presented an herbicidal efficacy similar to that of the free (technical) herbicides. Our results indicated the potential applicability of LDHs as supports for the preparation of slow release formulations of acid herbicides such as 2,4-D, MCPA, or picloram.
Assuntos
Herbicidas/administração & dosagem , Herbicidas/química , Hidróxidos/química , Ácido 2,4-Diclorofenoxiacético/administração & dosagem , Ácido 2,4-Diclorofenoxiacético/química , Ácido 2-Metil-4-clorofenoxiacético/administração & dosagem , Ácido 2-Metil-4-clorofenoxiacético/química , Ânions , Preparações de Ação Retardada , Herbicidas/análise , Cinética , Picloram/administração & dosagem , Picloram/química , Solo/análiseRESUMO
Metalaxyl and tricyclazole are two fungicides widely used in Spain in vineyard and rice crops respectively. In this study an investigation has been made of the effect of three organic amendments [two commercial amendments, solid fertiormont (SF) and liquid fertiormont (LF), and a residue from the olive oil production industry, alperujo (OW)] on fungicide fate in soils. Changes in soil porosity on amendment were studied by mercury intrusion porosimetry, sorption-desorption studies were performed by the batch equilibration method, dissipation of metalaxyl and tricyclazole in the soil was studied at - 33 kPa moisture content and 20 degrees C and leaching was studied in hand-packed soil columns. Amendments with SF and LF reduced soil porosity, while OW increased porosity through an increase in pore volume in the highest range studied. Tricyclazole sorbed to soils to a much higher extent than metalaxyl. With some exceptions, sorption of both fungicides increased on amendment, especially in the case of SF-amended soils, which rendered the highest K(oc) values. In soils amended with the liquid amendment LF, sorption either remained unaffected or decreased, and this decrease was much higher in the case of metalaxyl and a soil with 70% clay. In this clay soil, amendment with OW, of very high soluble organic matter content, also decreased metalaxyl sorption. Tricyclazole is more persistent in soil than metalaxyl, and both fungicides were found to be more persistent in amended soils than in unamended soils. Leaching of metalaxyl and tricyclazole in soil columns was inversely related to sorption capacity. The low recoveries of tricyclazole in leachates and in soil columns when compared with metalaxyl, a less persistent fungicide, were attributed to diffusion into micropores and to increase in sorption with residence time in the soil, both processes favoured by the low mobility of tricyclazole.
Assuntos
Alanina/análogos & derivados , Fungicidas Industriais/química , Solo/análise , Tiazóis/química , Adsorção , Alanina/química , PorosidadeRESUMO
Sorption-desorption interactions of pesticides with soil determine the availability of pesticides in soil for transport, plant uptake and microbial degradation. These interactions are affected by the physical and chemical properties of the pesticide and soil and, for some pesticides, their residence time in the soil. While sorption-desorption of many herbicides has been characterised, very little work in this area has been done on herbicide metabolites. The objective of this study was to characterise sorption-desorption of two sulfonylaminocarbonyltriazolinone herbicides, flucarbazone and propoxycarbazone, and their benzenesulfonamide and triazolinone metabolites in two soils with different physical and chemical properties. K(f) values for all four chemicals were greater in clay loam soil, which had higher organic carbon and clay contents than loamy sand. K(f-oc) ranged from 29 to 119 for the herbicides and from 42 to 84 for the metabolites. Desorption was hysteretic in every case. Lower desorption in the more sorptive system might indicate that hysteresis can be attributed to irreversible binding of the molecules to soil surfaces. These data show the importance of characterisation of both sorption and desorption of herbicide residues in soil, particularly in the case of prediction of herbicide residue transport. In this case, potential transport of sulfonylaminocarbonyltriazolinone herbicide metabolites would be overpredicted if parent chemical soil sorption values were used to predict transport.
Assuntos
Benzoatos/química , Praguicidas/química , Solo/análise , Sulfonamidas/química , Triazóis/química , Fatores de Tempo , BenzenossulfonamidasRESUMO
BACKGROUND: In Chile, there are inconsistencies in the management of depression in primary care settings, and the National Depression Program, currently in effect, was implemented without a standardized training program. The objective of this study is to evaluate the acceptability of a training program on the management of depression for primary care health teams. METHODS: The study was a randomized controlled trial, and two primary centers from the Metropolitan Region of Santiago were randomly selected to carry out the intervention training program. Pre-post surveys were applied, to evaluate expectations and satisfaction with the intervention, respectively. Descriptive and content analysis was carried out. RESULT: The sample consisted of 41 health professionals, 56.1% of who reported that their expectations for the intervention were met. All of the training activities were evaluated with scores higher than 6.4 (on a 1-7 scale). The trainers, the methodology, and the learning environment were considered strengths and facilitators of the program, while the limited duration of the training, the logistical problems faced during part of the program, and the lack of educational material were viewed as weaknesses. CONCLUSION: The intervention was well accepted by primary health care teams. However, the clinical impact in patients still has to be evaluated.