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Objetivo: Averiguar a efetividade da utilização da cirurgia de MOHS no manejo de tumores cutâneos tipo não melanoma em comparação a outros métodos de terapia. Métodos: O estudo consiste em uma revisão sistemática, cuja coleta de artigos ocorreu nas bases de dados MEDLINE, PubMed Central (PMC), LILACS e SciELO, utilizando os termos "Cirurgia de MOHS", "Câncer de pele", "Ensaio clínico", excluindo "melanoma". Resultados: Do total de 132 artigos identificados, foram considerados elegíveis 11. A análise dos artigos demonstrou que a CMM, comparada a outros métodos, apresentou resultados estéticos melhores, além de menor grau de complicações em tumores recorrentes e um custo/benefício variável com o país onde foi feita operação. A CMM também apresentou menores índices de recorrência em todos os estudos. Conclusão: No geral, a cirurgia de MOHS se mostrou um método terapêutico promissor. No entanto, existem ainda poucos estudos comparativos sobre a eficácia da CMM e os que existem se concentram em poucas regiões do mundo. (AU)
Objective: Evaluating the effectiveness of using MOHS surgery in the management of non-melanoma skin tumors compared to other therapy methods. Methods: The study consists of a systematic review, whose search for articles was performed using databases MEDLINE, PubMed Central (PMC), LILACS and SciELO, using the terms "MOHS surgery", "Skin cancer", "Clinical trial", excluding "melanoma". Results: from a total of 132 identified articles, 11 were considered eligible. The analysis of the articles showed that MMS, compared to other methods, presented better cosmetic results, in addition to a lower grade of complications in recurrent tumors and a variable cost/benefit according to the country where the surgery was performed. MMS also had lower recurrence rates in all studies. Conclusion:Overall, MOHS surgery has shown promising therapeutic results. However, there are still few comparative studies on the effectiveness of MMS and those that exist are concentrated in a few regions of the world. (AU)
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Humanos , Recurrencia , Neoplasias Cutáneas , Efectividad , Cirugía de Mohs , Costos y Análisis de Costo , MelanomaRESUMEN
Samples of galled roots, resembling those induced by root-knot nematodes, and rhizosphere soil were collected from potted plants of Ulmus parvifolia cvs. Allee and Drake in Lake County, Florida. Nematode species were identified using both molecular analysis and morphology of perineal patterns. Meloidogyne enterolobii and M. javanica were identified from U. parvifolia cv. Allee. Meloidogyne arenaria and M. javanica were identified from U. parvifolia cv. Drake. This is a first report of these nematode species infecting Chinese Elm in Florida.Samples of galled roots, resembling those induced by root-knot nematodes, and rhizosphere soil were collected from potted plants of Ulmus parvifolia cvs. Allee and Drake in Lake County, Florida. Nematode species were identified using both molecular analysis and morphology of perineal patterns. Meloidogyne enterolobii and M. javanica were identified from U. parvifolia cv. Allee. Meloidogyne arenaria and M. javanica were identified from U. parvifolia cv. Drake. This is a first report of these nematode species infecting Chinese Elm in Florida.
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In October 2019, samples of galled roots with rhizosphere soil were collected from declining Elaeocarpus decipiens in Hernando County, Florida. Extracted root-knot nematodes were identified by both molecular and morphological methods as Meloidogyne enterolobii. This is a first report of this regulated root-knot nematode on Elaeocarpus decipiens in Florida.In October 2019, samples of galled roots with rhizosphere soil were collected from declining Elaeocarpus decipiens in Hernando County, Florida. Extracted root-knot nematodes were identified by both molecular and morphological methods as Meloidogyne enterolobii. This is a first report of this regulated root-knot nematode on Elaeocarpus decipiens in Florida.
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Meloidogyne christiei isolated from turkey oak, Quercus laevies, from the type locality in Florida was characterized using isozyme profiles and ribosomal and mitochondrial gene sequences. The phenotype N1a detected from a single egg-laying female of M. christiei showed one very strong band of malate dehydrogenase (MDH) activity; however, no esterase (EST) activity was identified from macerate of one or even 20 females per well. Phylogenetic relationships within the genus Meloidogyne as inferred from Bayesian analysis of partial 18S ribosomal RNA (rRNA), D2-D3 of 28S rRNA, internal transcribed spacer (ITS) rRNA, and cytochrome oxidase subunit II (COII)-16S rRNA of mitochondrial DNA (mtDNA) gene fragments showed that M. christiei formed a separate lineage within the crown group of Meloidogyne and its relationships with any of three Meloidogyne clades were not resolved.
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Sting nematode (Belonolaimus longicaudatus) is an economically important ectoparasitic nematode that is highly pathogenic on a wide range of agricultural crops in sandy soils of the southeastern United States. Although this species is commonly found in Florida in hardwood forests and as a soilborne pathogen on turfgrasses and numerous agronomic and horticultural crops, it has not been reported infecting peanut. In the summers of 2012 and 2013, sting nematode was found infecting three different peanut cultivars being grown on two separate peanut farms in Levy County, FL. The damage consisted of large irregular patches of stunted, chlorotic plants at both farms. The root systems were severely abbreviated and there were numerous punctate-like isolated lesions observed on pegs and pods of infected plants. Sting nematodes were extracted from soil collected around the roots of diseased peanut over the course of the peanut season at both farm sites. Peanut yield from one of these nematode-infested sites was 64% less than that observed in areas free from sting nematodes. The morphological characters of the nematode populations in these fields were congruous with those of the original and other published descriptions of B. longicaudatus. Moreover, the molecular analyses based on the sequences of D2/D3 expansion fragments of 28S rRNA and internal transcribed spacer (ITS) rRNA genes from the nematodes further collaborates the identification of the sting nematode isolates as B. longicaudatus. The sequences were deposited in GenBank (accession no. KF963097, KF963098 for ITS, and KF96399, KF963100 for D2-D3). The results of the phylogenetic analysis using the sequences of these isolates from peanut compared with those of other isolates from Florida suggests that the sting nematode from both peanut farms are genetically close to B. longicaudatus populations occurring in the state. Peanut plants inoculated with both nematode isolates showed punctate-like isolated lesions on pods and pegs, and an abbreviation of their root systems, whereas those symptoms were not observed on noninoculated peanut plants. To our knowledge, this is the first report of large-scale field damage caused by sting nematode infecting peanut grown under field conditions in Florida.
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Foram utilizadas 350 aves da linhagem comercial Bovans White, com o objetivo de avaliar a associação de carboidrases e fitase em dietas valorizadas sobre o desempenho e qualidade dos ovos de poedeiras leves. O delineamento experimental foi inteiramente ao acaso, com 5 tratamentos e 7 repetições. Os tratamentos foram: T1- Controle positivo sem adição de enzimas e sem valorização dos nutrientes; T2- Controle negativo (CN) 1, valorizando em 1,5% e 6% a EMA (kcal/kg), respectivamente para o milho e o farelo de soja, e em 2% a proteína bruta (PB) e os aminoácidos digestíveis limitantes mais a matriz completa para a enzima fitase; T3- CN 2, valorizando em 1,5% e 6% a EMA (kcal/kg), respectivamente para o milho e o farelo de soja, e em 2% a proteína bruta (PB) e os aminoácidos digestíveis limitantes mais a matriz incompleta para a enzima fitase; T4- suplementado com 100g ton-1 de carboidrase e 30g ton-1 de fitase; T5- suplementado com 100g ton-1 de carboidrase e 30g ton-1 de fitase. Os tratamentos controle positivo, T2, T3, T4 e T5, com ou sem suplementação enzimática, garantiram o desempenho no que diz respeito ao consumo de ração, produção, peso e perdas de ovos e qualidade da casca.
A total of 350 commercial Bovans White laying hens were used to evaluate the association of carbohydrases and phytase in enriched diets and its effects on performance and egg quality of laying hens. The experiment used a randomized design with five treatments and seven replicates. The treatments were: 1. Positive control without added enzymes and without nutrient enrichment, 2. Negative control (NC) 1 with 1.5% and 6% AME (kcal/kg) enrichment for corn and soybean meal respectively, 2% crude protein (CP) enrichment, and digestible limiting digestible amino acids plus the full matrix for the phytase enzyme; 3. NC 2 with 1.5% and 6% AME (kcal/kg) enrichment, respectively, for corn and soybean meal and 2% crude protein (CP) enrichment, and digestible limiting amino acids plus the sparse matrix for the phytase enzyme, 4. NC 1 supplemented with 100 g ton-1 carbohydrase and 30g ton-1 phytase, 5. NC 2 supplemented with 100 g ton-1 carbohydrase and 30g ton-1 phytase. According to the results, the positive control treatments, NC1 and NC2, with or without enzyme supplementation, showed guaranteed performance for feed intake, egg yield, weight, egg loss and shell quality.
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Animales , Cáscara de Huevo/anomalías , Alimentación Animal/análisis , Alimentación Animal/normasRESUMEN
Roots of laurel oak (Quercus laurifolia Michx.), member of the family Fagaceae, were found to be heavily galled by the pecan root-knot nematode, Meloidogyne partityla, in two separate home gardens between 2010 and 2012, in Alachua Co., FL. Distinct round galls were observed on secondary and tertiary roots. Internally, root-knot nematode females were clearly visible when the roots were thinly sliced and egg masses were seen protruding from the root surfaces. The nematode species identification was performed using morphology of the male stylet, selected characters of the second-stage juveniles (J2), female perineal patterns, and esterase (EST) and malate dehydrogenase (Mdh) isozyme phenotypes. Morphology of perineal patterns of females, body, stylet, and tail length of the J2 and males all matched those of the original description of M. partityla (2). A swollen deeply grooved rectum was observed in the J2. The male stylet had a blunt tip with a prominent thickening at the junction between the cone and shaft. The stylet knobs of males and females were bipartite, each incised by a deep medium longitudinal groove (2). The isozyme phenotypes (EST = Mp3; Mdh = N1a) were consistent with those previously reported for M. partityla from Florida (1). Mitochondrial DNA (mtDNA) (3) and ribosomal internal transcriber spacer (ITS) DNA (4) of females were amplified to further confirm the nematode species identification. The mtDNA amplification using the C2F3/1108 primer set (3) and the ITS amplification using a recently available M. partityla specific primer set (4) produced fragments of approximately 530 bp and 550 bp, respectively. These were consistent with those already reported for this nematode species. This first report of a plant host for the pecan root-knot nematode outside of the family Juglandaceae indicates that the nematode may have migrated from Quercus species to pecan trees during the period when orchards were being established in Florida. To our knowledge, this is the first report of the pecan root-knot nematode infecting laurel oak. References: (1) J. A. Brito et al. Nematology 10:757, 2008. (2) Kleynhans, K. P. N. Phytophylatica 18:103, 1986. (3) T. O. Powers et al., J. Nematol. 37:226, 2005. (4) R. A. Stamler. M. S. thesis, New Mexico State University, Las Cruces, 2009.
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The present study was developed using 864 Hy-Line W36 laying hens (42 to 58 weeks of age) with a randomized experimental design in a 4x3 factorial arrangement, with five replicates and 12 birds per experimental unit and 4 evaluation periods of 28 days each. The digestible lysine levels studied were 0.675%, 0.743%, 0.811% and 0.879%, and the digestible threonine levels were 0.542%, 0.596% and 0.650%. The performance and egg quality was evaluated. There were no significant effects on the egg production, specific gravity, albumen and yolk percentage and total solids in albumen and yolk for birds submitted to the different dietary digestible lysine and threonine levels. There was significant interaction between these amino acids on the egg shell percentage and Haugh unit in fresh eggs. There was a decreasing linear effect on the feed intake with increase of digestible lysine level. Egg weight, egg mass and feed conversion demonstrated a quadratic effect with the increase of the digestible lysine level with the best results in the diets with 0.754, 0.772 and 0.795% of digestible lysine, respectively.
O presente trabalho foi desenvolvido utilizando 864 poedeiras Hy-Line W36 (42 a 58 semanas de idade) em um delineamento inteiramente casualizado no esquema fatorial 4x3 com 5 repetições e 12 aves por parcela e 4 períodos de avaliação de 28 dias cada. Os níveis de lisina digestível estudados foram 0,675%; 0,743%; 0,811% e 0,879%, e os de treonina digestível de 0,542%, 596% e 0,650%. Foram avaliados o desempenho e a qualidade dos ovos. Não houve efeitos significativos sobre a produção de ovos, gravidade específica, proporção de clara ou albúmen e seus respectivos teores de sólidos totais para poedeiras submetidas aos respectivos níveis de lisina e treonina na ração. Houve interação entre os níveis de treonina e lisina, para porcentagem de casca e unidade Haugh. Houve redução linear no consumo de ração em função do aumento dos níveis de lisina digestível na ração. Houve comportamento quadrático para peso dos ovos, massa dos ovos e conversão alimentar em função dos níveis de lisina digestível, estimando-se níveis ótimos para respectivas características em 0,754; 0,772 e 0,795%, respectivamente.
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Euphorbia punicea (Euphorbiaceae), commonly known as Jamaican poinsettia, is an evergreen shrub with dark green leaves and flashy red bracts. Bracts are sharply contrasted by rosettes of dark green leaves and can be observed in early summer, spring, fall, and winter. This shrub, native to Jamaica, is suitable in southern climates both in the landscape and as a seasonal patio container plant. Outdoors, the plants can reach as high as 5 meters. In January of 2012, E. punicea plants growing in an ornamental nursery in Dade Co., Florida, were observed with stunted growth and yellowing leaves. Root systems of affected plants were collected and sent to the Florida Department of Agriculture and Consumer Services, Nematology Laboratory, Gainesville, FL. Root systems showing symptoms of root-knot nematode infections were heavily galled and had already started rotting. Galls were observed in the primary, secondary, and tertiary roots. Species identification was initially performed using morphology and morphometrics. The morphology of the perineal patterns and measurements of selected characters of the second-stage juveniles fit those of the original description for M. enterolobii (3). The nematode species identification was confirmed using PCR to amplify mtDNA with the C2F3/1108 primer set (1) and a species-specific SCAR primer set, MK7-F/MK7-R (2). The PCR products were approximately 700 bp for mtDNA and approximately 520 bp for the SCAR, which were identical to those previously reported for M. enterolobii (1, 2). Sanitation practices should be implemented to avoid the spread of this nematode species within and between ornamental nurseries. Planting material should be produced in media free of this pathogen to avoid its introduction into uninfested nurseries and landscape areas. M. enterolobii has a wide host range, including cover and vegetable crops, fruit trees, herbs, and ornamental and weed plants. To our knowledge, this is the first report worldwide of E. punicea as a host of M. enterolobii. References: (1) T. O. Powers et al. J. Nematol. 37:226, 2005. (2) M. S. Tigano et al. Plant Pathol. 59:1054, 2010. (3) B. Yang and J. D. Eisenback. J. Nematol. 15:381, 1983.
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BACKGROUND: The incidence of thyroglossal duct cyst (TDC) carcinoma is uncommon (approximately 1%) and rarely reported in the literature. Treatment modalities have included tumourectomy, Sistrunk's procedure and/or total thyroidectomy. AIM: To try and determine the most adequate surgical approach for papillary thyroid carcinoma (PTC) arising in TDC. RESULTS: We reviewed the clinical charts of 22 patients with PTC of TDC treated between January 1974 and December 2008 (0.63% of the total of 3458 patients with PTC treated over that period). All patients underwent the Sistrunk's procedure. Fourteen (64%) were submitted to total thyroidectomy and 11 of these patients were ablated with lodine131. Seven (50%) of the 14 patients treated with total thyroidectomy had tumour both in the thyroid gland and in TDC but lymph node metastases were present only in four. None of the patients died of the disease and all of them are still alive without recurrence with a mean follow-up of 8 years (range: 2-27 years). The mean survival rate of the patients submitted to total thyroidectomy (n= 14) was not statistically different from that of patients treated with the Sistrunk's procedure alone (9.23 +/- 7.65 vs. 8.95 +/- 6.22, p= 0.940). CONCLUSION: Papillary thyroid carcinoma arising in thyroglossal duct cysts is a very rare malignant tumour. In spite of the multifocal character of several of our cases, their analysis showed that the prognosis in the vast majority of patients with TDC carcinoma is excellent. Moreover, we found no relation between outcome and surgical procedure.
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Carcinoma Papilar/patología , Quiste Tirogloso/patología , Neoplasias de la Tiroides/patología , Adolescente , Adulto , Carcinoma Papilar/terapia , Femenino , Humanos , Radioisótopos de Yodo/uso terapéutico , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Quiste Tirogloso/terapia , Neoplasias de la Tiroides/terapia , Tiroidectomía , Adulto JovenRESUMEN
Avaliaram-se o desempenho, o coeficiente de digestibilidade da matéria seca (CDMS), da proteína bruta (CDPB), a retenção aparente de cálcio (Ca) e fósforo (P) e a energia metabolizável aparente corrigida para balanço de nitrogênio (EMAn) de dietas suplementadas com altos teores de fitase (FTU) para frangos, até 35 dias de idade. Foram utilizados 1848 pintos, distribuídos em delineamento inteiramente ao acaso, com sete tratamentos e oito repetições de 35 aves. Os tratamentos foram: T1: dieta-controle; T2: dieta com inclusão de 1.500FTU/kg; T3: 3.000FTU/kg; T4: 4.500FTU/kg; T5: 6.000FTU/kg; T6: 8.000FTU/kg e T7: 10.000FTU/kg de ração. No 10º e 28º dias de experimento, quatro e três aves, respectivamente, foram transferidas para gaiolas de metabolismo. A partir da inclusão de 4.500FTU/kg, o desempenho das aves de 1 a 35 dias foi semelhante ao das aves do grupo-controle (P>0,05). Não houve diferença (P>0,05) entre os tratamentos nos CDPB e nos valores de EMAn, porém, na fase inicial, observou-se maior aproveitamento da MS com os altos níveis de fitase (P<0,05). Em relação à retenção de Ca e P, houve efeito positivo da suplementação enzimática, com aumento significativo do uso desses minerais pelas aves. Concluiu-se que é possível suplementar altos teores de fitase valorando adequadamente os nutrientes da dieta.
The digestibility of dry matter (DMD), and of crude protein (CPD), the apparent retention of calcium (Ca) and phosphorus (P) and apparent metabolizable energy corrected by nitrogen balance (AME) of diets supplemented with high levels of phytase (FTU) for broilers, 35 days old were evaluated. A total of 1848 chicks were distributed in a completely randomized experiment with seven treatments and eight repetitions. The treatments were: T1: control diet, T2: inclusion of 1,500FTU/kg; T3: 3,000FTU/kg; T4: 4,500FTU/kg; T5: 6,000FTU/kg; T6:8,000FTU/kg; and T7: 10,000FTU/kg feed. On the 10th and 28th days of the experiment, four and three birds, respectively, were transferred to metabolism cages. An addition of 4,500FTU/kg from 1 to 35 days resulted in a performance similar to the control group (P>0.05). There was no difference (P>0.05) among treatments for DMD and AME, however, during the initial phase there was a higher use of MS with high levels of phytase (P<0.05). Regarding the retention of Ca and P, a positive effect of enzyme supplementation significantly increased the use of these minerals by birds. It is possible that high levels of supplemental phytase adequate valuing the nutrients.
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Animales , /análisis , Aves de Corral , Alimentación Animal/análisis , Enfermedades Carenciales/veterinariaRESUMEN
Avaliaram-se a retenção aparente, a deposição hepática, tecidual e plasmática, bem como a eficiência da glutationa peroxidase hepática e plasmática em frangos de corte alimentados com diferentes níveis e fontes de selênio. Utilizaram-se 300 pintos machos com 14 dias, submetidos a um esquema fatorial 3x3 + 1 (três níveis de Se - 0,150; 0,300; 0,450ppm, e três fontes comerciais de Se - uma inorgânica e duas orgânicas + um tratamento controle sem suplementação), em DIC. Do primeiro ao 14º dia de idade - período de depleção -, as aves receberam rações basais sem suplementação de selênio. Aos 14 dias, receberam as dietas com selênio, por um período de 14 dias, sendo coletadas as excretas nos últimos quatro dias. A retenção de selênio foi relativamente alta. O uso da fonte orgânica A em níveis crescentes apresentou menor queda na retenção aparente de selênio. As fontes orgânicas participaram mais ativamente nas atividades de tecidos de forma geral, e a fonte inorgânica foi neutralizada no tecido hepático. A eficiência dessa enzima no plasma aumentou linearmente quando se elevaram os níveis dietéticos. Para a fonte inorgânica, não houve mudança nesta eficiência.
We evaluated the apparent retention, the hepatic, tissue and plasmatic deposition as well as the efficiency of the enzyme hepatic and plasmatic Glutathione Peroxidase in broiler chickens fed different sources and levels of selenium. 300 male Cobb- 500 chicks aged 14 days were submitted to a factorial scheme 3x3+1 (three levels - 0.150; 0.300; 0.450ppm, three commercial sources - one inorganic and two organic + one control treatment without a supplementation) in CRD. The first 14 days of age (depletion period) the birds were fed basal diets without a supplementation of selenium. At 14 days the birds were given the diets with selenium for a period for 14 days, and the excreta collected in the last four days. The work suggested that the selenium retentions were relatively high, due to the use of organic source A at growing levels they presented a lower decrease in apparent retention of selenium. The organic sources participated more actively in the activities of tissues in general and the inorganic source is neutralized in the hepatic tissue. The efficiency of this enzyme in plasma was increased linearly, when we increased dietary levels for the inorganic source there was no change in efficiency.
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Animales , Glutatión Peroxidasa , Fisiología , SelenioRESUMEN
A novel bacterium of the genus Pasteuria was discovered parasitizing bacterivorous nematodes of the genus Bursilla, in selected bermudagrass (Cynodon) field plots in Davie, FL, USA. Soil containing this bacterium was sampled and supplied with bi-weekly inoculations of cultured species of the genus Bursilla in order to build and maintain a source of endospores for continuous in vivo conservation of the bacteria for further study and characterization. 16S rRNA gene sequence similarities supported its congeneric ranking with other members of the genus Pasteuria that have been identified from nematodes and cladocerans. There were, however, no clear sister candidates for this organism, which supported the evidence of endospore ultrastructure and host-range studies, suggesting it belonged to a novel taxon. Because members of the genus Pasteuria cannot yet be isolated, definitive type strains could not be maintained; therefore, the name 'Candidatus Pasteuria aldrichii' is proposed for this organism.
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Pasteuria/clasificación , Pasteuria/aislamiento & purificación , Rhabditoidea/microbiología , Microbiología del Suelo , Animales , Técnicas de Tipificación Bacteriana , Composición de Base , Catalasa/metabolismo , Pared Celular/química , China , Análisis por Conglomerados , ADN Bacteriano/química , ADN Bacteriano/genética , ADN Ribosómico/química , ADN Ribosómico/genética , Ácido Diaminopimélico/análisis , Ácidos Grasos/análisis , Concentración de Iones de Hidrógeno , Datos de Secuencia Molecular , Oxidorreductasas/metabolismo , Pasteuria/patogenicidad , Pasteuria/fisiología , Peptidoglicano/química , Fosfolípidos/análisis , Filogenia , Quinonas/análisis , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Cloruro de Sodio/metabolismo , Esporas Bacterianas/citología , Temperatura , ÁrbolesRESUMEN
The use of iteratively reweighted least squares (IRLS) has recently been described as an alternative to ordinary least squares with heteroscedastic data, in the calibration of (109)Cd KXRF systems for in vivo bone lead measurements. This work addresses the use of weighted least squares (WLS) with two different weighting functions and no iteration, with that same data set. The functions are defined as the inverse of the variance of observed ratios of lead to coherent peak amplitudes and the inverse of the square of the error reported by the Marquardt fitting program for these ratios. The results show that if no iteration is implemented when using WLS, then the two weighting functions are highly inefficient in homogenizing the residual variance. Moreover, both methods estimate much more imprecise calibration intercepts and slopes than did the IRLS method. Work is in progress to investigate the implementation of IRLS with these weighting functions, with the focus on the selection of the best function for residuals to be used in each iteration stage.
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Huesos/química , Radioisótopos de Cadmio/química , Plomo/análisis , Espectrometría por Rayos X/instrumentación , Espectrometría por Rayos X/normas , Algoritmos , Animales , Radioisótopos de Cadmio/análisis , Calibración , Canadá , Interpretación Estadística de Datos , Humanos , Análisis de los Mínimos Cuadrados , Análisis de Regresión , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Espectrometría por Rayos X/métodosRESUMEN
The use of least-squares regression to probe the level of lead contamination of plaster of Paris standards in the calibration of (109)Cd KXRF systems for bone lead measurement, as well as the use of iteratively reweighted least-squares (IRLS) in the case of violation of the assumptions for ordinary least-squares (OLS), is discussed here. One common violation is non-uniform residual variance, which makes the use of OLS inappropriate due to strong influence of points with large variance on the calibration line and variance of the slope and intercept. Comparison between OLS and IRLS in that case showed that IRLS estimates of the intercept are significantly smaller and more precise than OLS estimates, while a less marked increase in the calibration slope is observed when IRLS is used. Moreover, OLS underestimates bone lead concentrations at low levels of lead exposure and overestimates those concentrations at higher levels. These discrepancies are smaller in magnitude than the measurement uncertainty of conventional systems, except for high concentrations. For the newly developed cloverleaf systems, the suggested differences at bone lead concentrations below 17 ppm are comparable to the minimum detection limit, but are larger than the measurement uncertainty for bone lead concentrations above 60 ppm.
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Algoritmos , Huesos/química , Radioisótopos de Cadmio/química , Plomo/análisis , Espectrometría por Rayos X/instrumentación , Espectrometría por Rayos X/normas , Radioisótopos de Cadmio/análisis , Calibración , Canadá , Interpretación Estadística de Datos , Análisis de los Mínimos Cuadrados , Análisis de Regresión , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Espectrometría por Rayos X/métodosRESUMEN
Severe stunting and extensive root galling were observed on tomato rootstock (Solanum lycopersicum L. cv. Maxifort) resistant to Meloidogyne incognita (Kofoid & White, 1919) Chitwood, 1949, M. javanica (Treub, 1885), and M. arenaria (Neal, 1889) Chitwood, 1949 and cucumber (Cucumis sativus L. cv. Loustik) from two commercial greenhouses in the cantons Aargau and Lucerne in northern Switzerland. Examination of the roots of infected plants revealed the presence of root-knot nematodes in large numbers. Juveniles, males, and females were isolated, and the species was determined on the basis of morphological characteristics, including the female perineal pattern. Identification was confirmed by female esterase (Est) and malate dehydrogenase (MdH) electrophoresis (20 each for Est and MdH). All methods of identification were consistent with M. enterolobii Yang & Eisenback, 1983 (4). For further confirmation, type material of M. enterolobii (from the original host Enterolobium contortisiliquum (Vell.) Morong) from China (4) was used. Furthermore, comparison of the sequence data from 12 individuals of each of the two Swiss populations and the type material of a 310-bp fragment of cytochrome oxidase I (COI), a 723-bp fragment covering the internal transcribed spacer (ITS) region 1, 5.8s, ITS2, and part of the 26s, the mtDNA 63-bp repeat region, and a 780-bp fragment of the intergenic spacer region (1-3) showed 100% homology and confirmed the identification as M. enterolobii. The species M. enterolobii is of great importance because it is able to reproduce on resistant tobacco, pepper, watermelon, and tomato (4). To our knowledge, this is the first report of M. enterolobii in Switzerland. References: (1) M. A. M. Adam et al. Plant Pathol. 56:190, 2007. (2) V. C. Blok et al. Nematology 4:773, 2002. (3) T. C. Vrain et al. Fundam. Appl. Nematol. 15:565, 1992. (4) B. Yang and J. D. Eisenback. J. Nematol. 15:381, 1983.
RESUMEN
Paulownia elongata S.Y. Hu (Scrophulariaceae) is a fast-growing tree cultivated for highly prized timber. In April 2007, root-knot nematodes were found to be infecting 5-year-old plants of P. elongata growing on a farm in Levy County, Florida. Symptoms included leaf yellowing, stunted growth, and reduced trunk diameter. Infected roots were severely galled and frequently rotted. Large and coalesced galls were observed on secondary roots and distinct galls were present on tertiary roots. Species identifications were done by morphological characters of females and isozyme phenotypes (esterase and malate dehydrogenase) extracted from young egg-laying females and resolved with polyacrylamide gel electrophoresis in a BioRad Mini Protean III system (BioRad, Hercules, CA). Four species of root-knot nematodes were found to be infecting P. elongata. Morphology of perineal patterns and the isozyme phenotypes were consistent with those of M. arenaria, M. incognita, M. javanica, and M. mayaguensis (1). M. incognita and M. javanica have been described earlier on P. fortunei and P. tomentosa (2), but to our knowledge, this is the first report of P. elongata as a host of these four Meloidogyne spp. References: (1) R. M. D. G. Carneiro et al. Nematology 6:287, 2004. (2) V. Sharma and M. D. Mehrotra. Indian J. For. 22:149, 1999.
RESUMEN
Meloidogyne mayaguensis is a damaging root-knot nematode able to reproduce on root-knot nematode-resistant tomato and other economically important crops. In a growth chamber experiment conducted at 22 and 33 degrees C, isolate 1 of M. mayaguensis reproduced at both temperatures on the Mi-1-carrying tomato lines BHN 543 and BHN 585, whereas M. incognita race 4 failed to reproduce at 22 degrees C, but reproduced well at 33 degrees C. These results were confirmed in another experiment at 26 +/- 1.8 degrees C, where minimal or no reproduction of M. incognita race 4 was observed on the Mi-1-carrying tomato genotypes BHN 543, BHN 585, BHN 586 and 'Sanibel', whereas heavy infection and reproduction of M. mayaguensis isolate 1 occurred on these four genotypes. Seven additional Florida M. mayaguensis isolates also reproduced on resistant 'Sanibel' tomato at 26 +/- 1.8 degrees C. Isolate 3 was the most virulent, with reproduction factor (Rf) equal to 8.4, and isolate 8 was the least virulent (Rf = 2.1). At 24 degrees C, isolate 1 of M. mayaguensis also reproduced well (Rf >/= 1) and induced numerous small galls and large egg masses on the roots of root-knot nematode-resistant bell pepper 'Charleston Belle' carrying the N gene and on three root-knot nematode-resistant sweet pepper lines (9913/2, SAIS 97.9001 and SAIS 97.9008) carrying the Tabasco gene. In contrast, M. incognita race 4 failed to reproduce or reproduced poorly on these resistant pepper genotypes. The ability of M. mayaguensis isolates to overcome the resistance of tomato and pepper genotypes carrying the Mi-1, N and Tabasco genes limits the use of resistant cultivars to manage this nematode species in infested tomato and pepper fields in Florida.
RESUMEN
The effect of covariance between the K alpha and K beta lead peak concentrations on the uncertainty in the (109)Cd K x-ray fluorescence measurement of lead in bone is addressed here. It is commonly believed that this covariance arises as a result of the mutual dependence of the ratios of x-ray to coherent amplitudes on the same coherent peak amplitude. Previous work assumes statistical independence between spectral quantities of interest, crudely estimates the uncertainties in the lead peak concentrations, and suggests that the effect of covariance on the measurement uncertainty is small and can be ignored. Consequently, the current method followed by most laboratories reports the measurement uncertainty as if the fluctuations in the measured peak concentrations were independent. The robustness of such assumption, however, is undermined by existing epidemiological data. This paper assesses the magnitude of the covariance effect, using a method based on the observed significant correlations between the ratios of x-ray to coherent peak amplitudes in series of repeat phantom measurements. The revised uncertainties following this approach can exceed the uncertainties estimated by the accepted method by as much as 40%, which suggests a much stronger effect of covariance on the measurement uncertainty than previously reported.