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1.
J Econ Entomol ; 114(6): 2277-2289, 2021 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-34447985

RESUMO

Studies were conducted with ozone gas fumigation under vacuum as a methyl bromide alternative against life stages of coffee berry borer (CBB) Hypothenemus hampei (Ferrari) (Coleoptera: Curculionidae: Scolytinae), and the urediniospores of coffee leaf rust (CLR), Hemileia vastatrix Berkeley & Broome (Basidiomycota: Pucciniales) in green coffee, Coffea spp. L. Fumigation with 10,000 ppm O3 gas under -25.4 mm Hg vacuum1 at 13.0 ± 3.0°C for 6.0 h killed all CBB larvae, pupae, and adults, but did not kill all CBB eggs (~15% survival). Mortality of CLR urediniospores was 100% within the first hour of the 6-h fumigation. Ozone fumigation had no adverse effects on coffee quality. Results indicated that CBB adult hitchhikers may be the only target life stage of quarantine concern, and additional studies focused on this stage. CBB adult survival and reproduction decreased significantly at moisture contents ≤20%, and F1 generation survival did not occur in green coffee at moisture contents ≤15%. As the international standard for green coffee moisture content is 9-12%, adult CBB should not survive or reproduce in exported dry green coffee. Standard industry processing of harvested coffee cherries to the green coffee stage using either mechanical- or sun-drying eliminated CBB infestations from the field. A systems approach is recommended for exporting green coffee to control CBB and CLR that includes eliminating CBB life stages with standard processing methods, reducing moisture content to 9-12% to prevent egg deposition, survival or reproduction, and O3 fumigation to ensure quarantine security against potential CBB adult hitchhikers.


Assuntos
Basidiomycota , Coffea , Ozônio , Gorgulhos , Animais , Café , Fumigação , Havaí , Doenças das Plantas , Medição de Risco , Vácuo
2.
Phys Med Biol ; 66(11)2021 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-33853055

RESUMO

In this work we show the first microdosimetry measurements on a low energy proton beam with therapeutic-equivalent fluence rates by using the second generation of 3D-cylindrical microdetectors. The sensors belong to an improved version of a novel silicon-based 3D-microdetector design with electrodes etched inside silicon, which were manufactured at the National Microelectronics Centre (IMB-CNM, CSIC) in Spain. A new microtechnology has been employed using quasi-toroid electrodes of 25µm diameter and a depth of 20µm within the silicon bulk, resulting in a well-defined cylindrical radiation sensitive volume. These detectors were tested at the 18 MeV proton beamline of the cyclotron at the National Accelerator Centre (CNA, Spain). They were assembled into an in-house low-noise readout electronics to assess their performance at a therapeutic-equivalent fluence rate. Microdosimetry spectra of lineal energy were recorded at several proton energies starting from 18 MeV by adding 50µm thick tungsten foils gradually at the exit-window of the cyclotron external beamline, which corresponds to different depths along the Bragg curve. The experimentalyF¯values in silicon cover from (5.7 ± 0.9) to (8.5 ± 0.4) keV µm-1in the entrance to (27.4 ± 2.3) keV µm-1in the distal edge. Pulse height energy spectra were crosschecked with Monte Carlo simulations and an excellent agreement was obtained. This work demonstrates the capability of the second generation 3D-microdetectors to assess accurate microdosimetric distributions at fluence rates as high as those used in clinical centers in proton therapy.


Assuntos
Terapia com Prótons , Silício , Método de Monte Carlo , Prótons , Radiometria
3.
Artigo em Inglês | MEDLINE | ID: mdl-33668892

RESUMO

Long-term care coverage is not integrated into an individual's retirement strategy. It is an additional public health service that is not considered into private pension funds. Nevertheless, this coverage is not sufficient due to the problems of financial sustainability of the public pension systems. However, there are large sums in pension plans dedicated to paying retirement pensions that can be transformed into support for long-term care coverage. This paper develops a mechanism of pension transformation through the different mortality of the beneficiary when becoming a dependent beneficiary. This mechanism allows the beneficiary to convert their pension to LTC support at their own choice, without increasing the cost of the private pension scheme. The proposed model provides consistency in the pension that a retiree receives and adapts it to a retiree's life expectancy: the retiree receives a higher pension when he/she needs it most.


Assuntos
Pensões , Aposentadoria , Feminino , Expectativa de Vida , Masculino , Salários e Benefícios
4.
Rev Neurol ; 63(11): 488-496, 2016 Dec 01.
Artigo em Espanhol | MEDLINE | ID: mdl-27874165

RESUMO

INTRODUCTION: The Montreal Cognitive Assessment (MoCA) is a brief screening test that assesses the general cognitive state. It has become very popular and useful as an alternative resource for the traditional Mini-Mental State Examination. AIM: To normalize and to standardize the MoCA taking into account the sociodemographic characteristics of the Spanish population (INE data, 2012). SUBJECTS AND METHODS: The present study is part of the Normacog Project. Seven hundred participants were recruited (older than 18 years old). The effect of age, level of education and sex was analyzed on the performance of MoCA and percentiles and scalar score for nine ranges of age and scalar score adjusted by the level of education. RESULTS: Results showed a significant effect of age, level of education and sex on the cognitive performance of MoCA. However, sex was only significant in two domains (attention and delayed recall). Age, education and sex explained from 1.0% to 32.3% of the variance of the performance. The older participants with lower level of formal education obtained the worse performance shown in MoCA. Percentiles and scalar score for each range of age, and scalar score adjusted by the level of education were obtained. CONCLUSION: The normative data of the MoCA is provided taking into account the Spanish sociodemographic characteristics for adults in Spain and the cut-off to distinguish between normal cognitive performance and mild cognitive impairment according to different range of ages have been proposed.


TITLE: Test de evaluacion cognitiva de Montreal: normalizacion y estandarizacion de la prueba en poblacion española.Introduccion. La evaluacion cognitiva de Montreal (MoCA) es un test de cribado breve que evalua el estado cognitivo general, y resulta un recurso alternativo, muy util, al tradicional test minimental. Objetivo. Normalizar y estandarizar el test MoCA, teniendo en cuenta las caracteristicas sociodemograficas de la poblacion española (datos INE, 2012). Sujetos y metodos. El estudio se enmarca dentro del proyecto Normacog, en el que se evaluo a 700 participantes (18-86 años). Se analizaron el efecto de la edad, el nivel educativo y el sexo sobre el rendimiento del test MoCA, y se crearon los percentiles, las puntuaciones escalares para nueve rangos de edad y la puntuacion escalar normalizada ajustada por edad y nivel educativo. Resultados. Los resultados mostraron un efecto significativo de la edad, el nivel educativo y el sexo sobre el rendimiento cognitivo en el test MoCA. Sin embargo, el sexo solo presento un efecto significativo sobre dos dominios cognitivos: atencion y recuerdo diferido. La edad, la educacion y el sexo explicaron entre el 1% y el 32,3% de la varianza en las variables analizadas del test. Los participantes mas mayores con menor nivel de educacion formal obtuvieron peor rendimiento cognitivo. Se obtuvieron los percentiles y las puntuaciones escalares para cada rango de edad y la puntuacion escalar normalizada individual. Conclusion. Se presentan los datos normativos del test MoCA adecuados a las caracteristicas sociodemograficas de la sociedad española y los puntos de corte propuestos para discriminar entre rendimiento cognitivo normal y deterioro cognitivo leve segun los diferentes rangos de edad.


Assuntos
Disfunção Cognitiva/diagnóstico , Testes de Estado Mental e Demência/normas , Humanos , Espanha
5.
Phys Med Biol ; 61(11): 4036-47, 2016 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-27163881

RESUMO

The commissioning of an ion beam for hadrontherapy requires the evaluation of the biologically weighted effective dose that results from the microdosimetric properties of the therapy beam. The spectra of the energy imparted at cellular and sub-cellular scales are fundamental to the determination of the biological effect of the beam. These magnitudes are related to the microdosimetric distributions of the ion beam at different points along the beam path. This work is dedicated to the measurement of microdosimetric spectra at several depths in the central axis of a (12)C beam with an energy of 94.98 AMeV using a novel 3D ultrathin silicon diode detector. Data is compared with Monte Carlo calculations providing an excellent agreement (deviations are less than 2% for the most probable lineal energy value) up to the Bragg peak. The results show the feasibility to determine with high precision the lineal energy transfer spectrum of a hadrontherapy beam with these silicon devices.


Assuntos
Radioterapia com Íons Pesados/instrumentação , Radiometria/instrumentação , Silício , Humanos , Transferência Linear de Energia , Método de Monte Carlo , Prótons
6.
Phys Med Biol ; 57(19): 6167-91, 2012 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-22971664

RESUMO

Neutron peripheral contamination in patients undergoing high-energy photon radiotherapy is considered as a risk factor for secondary cancer induction. Organ-specific neutron-equivalent dose estimation is therefore essential for a reasonable assessment of these associated risks. This work aimed to develop a method to estimate neutron-equivalent doses in multiple organs of radiotherapy patients. The method involved the convolution, at 16 reference points in an anthropomorphic phantom, of the normalized Monte Carlo neutron fluence energy spectra with the kerma and energy-dependent radiation weighting factor. This was then scaled with the total neutron fluence measured with passive detectors, at the same reference points, in order to obtain the equivalent doses in organs. The latter were correlated with the readings of a neutron digital detector located inside the treatment room during phantom irradiation. This digital detector, designed and developed by our group, integrates the thermal neutron fluence. The correlation model, applied to the digital detector readings during patient irradiation, enables the online estimation of neutron-equivalent doses in organs. The model takes into account the specific irradiation site, the field parameters (energy, field size, angle incidence, etc) and the installation (linac and bunker geometry). This method, which is suitable for routine clinical use, will help to systematically generate the dosimetric data essential for the improvement of current risk-estimation models.


Assuntos
Nêutrons/efeitos adversos , Sistemas On-Line , Órgãos em Risco/efeitos da radiação , Doses de Radiação , Radioterapia Assistida por Computador/efeitos adversos , Radioterapia Assistida por Computador/instrumentação , Aceleração , Humanos , Método de Monte Carlo , Imagens de Fantasmas , Terapia com Prótons/efeitos adversos , Terapia com Prótons/instrumentação , Dosagem Radioterapêutica
7.
Phys Med Biol ; 54(15): 4723-41, 2009 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-19622853

RESUMO

Modern dosimetry protocols are based on the use of ionization chambers provided with a calibration factor in terms of absorbed dose to water. The basic formula to determine the absorbed dose at a user's beam contains the well-known beam quality correction factor that is required whenever the quality of radiation used at calibration differs from that of the user's radiation. The dosimetry protocols describe the whole ionization chamber calibration procedure and include tabulated beam quality correction factors which refer to 60Co gamma radiation used as calibration quality. They have been calculated for a series of ionization chambers and radiation qualities based on formulae, which are also described in the protocols. In the case of high-energy photon beams, the relative standard uncertainty of the beam quality correction factor is estimated to amount to 1%. In the present work, two alternative methods to determine beam quality correction factors are prescribed-Monte Carlo simulation using the EGSnrc system and an experimental method based on a comparison with a reference chamber. Both Monte Carlo calculations and ratio measurements were carried out for nine chambers at several radiation beams. Four chamber types are not included in the current dosimetry protocols. Beam quality corrections for the reference chamber at two beam qualities were also measured using a calorimeter at a PTB Primary Standards Dosimetry Laboratory. Good agreement between the Monte Carlo calculated (1% uncertainty) and measured (0.5% uncertainty) beam quality correction factors was obtained. Based on these results we propose that beam quality correction factors can be generated both by measurements and by the Monte Carlo simulations with an uncertainty at least comparable to that given in current dosimetry protocols.


Assuntos
Método de Monte Carlo , Radiometria/instrumentação , Estudos de Viabilidade , Fótons , Doses de Radiação , Radiometria/métodos , Incerteza
8.
Med Biol Eng Comput ; 46(4): 373-80, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17828563

RESUMO

Significant deviations from the expected dose have been reported in the absolute dosimetry validation of an intensity modulated radiation therapy treatment when individual segments are analyzed. However, when full treatment is considered and all segment doses are added together, these discrepancies fade out, leading to overall dose deviations below a 5% action level. This contradictory behavior may be caused by a partial compensation between detector over-responding and under-responding for measurement conditions far from radiation equilibrium. We consider three treatment verification scenarios that may lead to ionization chamber miss-responding, namely: narrow beam irradiation, field penumbra location and multi-leaf collimator transmission contribution. In this work we have analyzed the response of three different ionization chambers with different active volume under these conditions by means of Monte Carlo (MC) simulation methods. Correction factors needed to convert the detector readout into actual dose to water were calculated by inserting the specific detector geometry (carefully modeled) into the simulations. This procedure required extensive use of parallel computing resources in order to achieve the desired level of uncertainty in the final results. The analysis of the simulations shows the relative contribution of each of the three previously mentioned miss-responding scenarios. Additionally, we provide some evidence on dose deviation compensation in multi-segment radiotherapy treatment verification.


Assuntos
Método de Monte Carlo , Radiometria/métodos , Radioterapia de Intensidade Modulada/normas , Humanos , Interpretação de Imagem Assistida por Computador , Imagens de Fantasmas , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador , Espalhamento de Radiação
9.
Phys Med ; 23(2): 58-66, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17568544

RESUMO

A new method for the measurement of output factors of narrow beams is presented in this work. By combining a new large area parallel plane ionization chamber (PTW model T34070) with a relative film dosimetry the output factors of small square fields of a 6 MV beam shaped by a MLC were measured. Several detectors (three ionization chambers, two solid state detectors and film) and Monte Carlo simulation were also employed to validate this new methodology and also to determine those detectors more suitable for narrow beam output factor determination. The proposed method for output factor measurement has shown to be in a very good agreement with diamond, diode and Monte Carlo results while it is insensitive to position displacements. Several uncertainties associated to the process of narrow beam dosimetry have also been addressed.


Assuntos
Radioterapia/instrumentação , Radioterapia/métodos , Simulação por Computador , Desenho de Equipamento , Humanos , Método de Monte Carlo , Dosagem Radioterapêutica
10.
Phys Med Biol ; 51(6): 1523-32, 2006 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-16510960

RESUMO

Reference dosimetry of photon fields is a well-established subject and currently available protocols (such as the IAEA TRS-398 and AAPM TG-51) provide methods for converting the ionization chamber (IC) reading into dose to water, provided reference conditions of charged particle equilibrium (CPE) are fulfilled. But these protocols cannot deal with the build-up region, where the lack of CPE limits the applicability of the cavity theorems and so the chamber correction factors become depth dependent. By explicitly including the IC geometry in the Monte Carlo simulations, depth-dependent dose correction factors are calculated for a PTW 30001 0.6 cm(3) ion chamber in the build-up region of the 6 MV photon beam. The corrected percentage depth dose (PDD) agrees within 2% with that measured using the NACP 02 plane-parallel ion chamber in the build-up region at depths greater than 0.4 cm, where the Farmer chamber wall reaches the phantom surface.


Assuntos
Aceleradores de Partículas , Radiometria/métodos , Calibragem , Íons , Método de Monte Carlo , Imagens de Fantasmas , Fótons , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador , Radioterapia de Alta Energia
11.
Phys Med Biol ; 50(24): 5921-33, 2005 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-16333164

RESUMO

Neutron production in radiotherapy facilities has been studied from the early days of modern linacs. Detailed studies are now possible using photoneutron capabilities of general-purpose Monte Carlo codes at energies of interest in medical physics. The present work studies the effects of modelling different accelerator head and room geometries on the neutron fluence and spectra predicted via Monte Carlo. The results from the simulation of a 15 MV Siemens PRIMUS linac show an 80% increase in the fluence scored at the isocentre when, besides modelling the components necessary for electron/photon simulations, other massive accelerator head components are included. Neutron fluence dependence on inner treatment room volume is analysed showing that thermal neutrons have a 'gaseous' behaviour and then a 1/V dependence. Neutron fluence maps for three energy ranges, fast (E > 0.1 MeV), epithermal (1 eV < E < 0.1 MeV) and thermal (E < 1 eV), are also presented and the influence of the head components on them is discussed.


Assuntos
Método de Monte Carlo , Nêutrons , Aceleradores de Partículas/instrumentação , Fótons
12.
Phys Med Biol ; 49(21): 4929-42, 2004 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-15584528

RESUMO

A method for commissioning an EGSnrc Monte Carlo simulation of medical linac photon beams through wide-field lateral profiles at moderate depth in a water phantom is presented. Although depth-dose profiles are commonly used for nominal energy determination, our study shows that they are quite insensitive to energy changes below 0.3 MeV (0.6 MeV) for a 6 MV (15 MV) photon beam. Also, the depth-dose profile dependence on beam radius adds an additional uncertainty in their use for tuning nominal energy. Simulated 40 cm x 40 cm lateral profiles at 5 cm depth in a water phantom show greater sensitivity to both nominal energy and radius. Beam parameters could be determined by comparing only these curves with measured data.


Assuntos
Algoritmos , Análise de Falha de Equipamento/métodos , Análise de Falha de Equipamento/normas , Modelos Biológicos , Aceleradores de Partículas/normas , Fótons/uso terapêutico , Radiometria/métodos , Simulação por Computador , Modelos Estatísticos , Método de Monte Carlo , Garantia da Qualidade dos Cuidados de Saúde/métodos , Garantia da Qualidade dos Cuidados de Saúde/normas , Proteção Radiológica/métodos , Proteção Radiológica/normas , Radiometria/instrumentação , Radiometria/normas , Dosagem Radioterapêutica/normas , Sensibilidade e Especificidade
13.
Rev Neurol ; 39(1): 1-6, 2004.
Artigo em Espanhol | MEDLINE | ID: mdl-15257519

RESUMO

INTRODUCTION: The availability of the interferon beta in its three forms at the moment available in our country and of glatiramer acetate has marked a point of flexion in the natural history of multiple sclerosis (MS), but the high cost of these treatments cause that its use is questioned. In this work we have studied the effectiveness and efficiency of the processing with interferon beta, and the cost-utility of these treatments in MS in Spain has been also analyzed. PATIENTS AND METHODS: For this work we studied 102 patients affected of RR MS, treated with the three interferons beta which we have available in our country. We used as control 330 patients who had participated in the pivotal clinical interferon trials with both interferon beta 1a. In these patients in addition to effectiveness data, we have studied the disability measured as area below curve and the quality of life (AVACs). We also calculated the economical costs, considering the relation cost-utility in our country. RESULTS: Besides to confirm the data of effectiveness of three interferons, in this study a saving of 23 days/year is demonstrated what corresponds to 0.063 AVACs. The additional cost of interferons is greater than the avoided cost until the fifth year of treatment in which the tendency is reversed in favor of the group of treated patients, if we assume that the same effectiveness that we found in the first years is maintained in the long term. CONCLUSION: The use of the treatment with interferon beta is justified by its effectiveness, efficacy and efficiency. The additional cost of the treatment will be compensated in the long term if the effectiveness of the interferon beta is maintained.


Assuntos
Análise Custo-Benefício , Interferon beta/economia , Interferon beta/uso terapêutico , Esclerose Múltipla Recidivante-Remitente/tratamento farmacológico , Esclerose Múltipla Recidivante-Remitente/economia , Adulto , Área Sob a Curva , Avaliação da Deficiência , Feminino , Humanos , Masculino , Anos de Vida Ajustados por Qualidade de Vida , Espanha , Resultado do Tratamento
14.
Phys Med Biol ; 49(10): 1905-14, 2004 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-15214532

RESUMO

We have analysed data on the free ion yield observed in liquid isooctane irradiated by 60Co gamma rays within the framework of the Onsager theory about initial recombination. Several distribution functions describing the electron thermalization distance have been used and compared with the experimental results: a delta function, a Gaussian-type function and an exponential function. A linear dependence between the free ion yield and the external electric field has been found at low-electric-field values (E < or = 1.2 x 10(3) V mm(-1)) in excellent agreement with the Onsager theory. At higher electric field values, we obtain a solution in power series of the external field using the Onsager theory.


Assuntos
Íons , Octanos/química , Física/métodos , Radioisótopos de Cobalto , Elétrons , Raios gama , Modelos Estatísticos , Modelos Teóricos , Método de Monte Carlo , Distribuição Normal , Radiação Ionizante
15.
Biomaterials ; 25(25): 5603-11, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15159076

RESUMO

Biodegradable and biocompatible materials are the basis for tissue engineering. As an initial step for developing vascular grafts, the in vitro biocompatibility of poly(epsilon-caprolactone) (PCL), recently suggested for several clinical applications, was evaluated in this study using L929 mouse fibroblasts. Different cellular aspects were analyzed in order to know the cell viability during cell culture on PCL films: adhesion, proliferation, morphology, LDH release and mitochondrial function. Since topography and other surface characteristics of materials play an essential part in cell adhesion, PCL membranes with either smooth or rough surface were prepared, characterized and used to carry out cell cultures. During short culture times, PCL produced a significant stimulation of mitochondrial activity evaluated by reduction of the MTT reagent. The results provide evidences of good adhesion, growth, viability, morphology and mitochondrial activity of cells on PCL films. Therefore, it can be concluded that PCL is a suitable and biocompatible material as a scaffold for vascular graft development.


Assuntos
Fibroblastos/metabolismo , Teste de Materiais , Poliésteres/química , Animais , Adesão Celular/fisiologia , Contagem de Células , Linhagem Celular Tumoral , Proliferação de Células , Complexo II de Transporte de Elétrons/metabolismo , Fibroblastos/ultraestrutura , Vidro/química , L-Lactato Desidrogenase/metabolismo , Membranas Artificiais , Camundongos , Microscopia de Força Atômica , Microscopia Eletrônica de Varredura , Poliestirenos/química , Propriedades de Superfície , Sais de Tetrazólio/metabolismo , Tiazóis/metabolismo
16.
Hum Biol ; 75(1): 117-27, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12713152

RESUMO

Two Y-chromosome DNA polymorphisms, the DYS19 microsatellite and the YAP (at locus DYS287), were tested in males from two autochthonous Basque populations from France and northern Navarre (Spain). The results are compared to those obtained for the same genetic markers in 32 populations from Europe, northern Africa, and western Asia. The high predominance of the DYS19*11 (190-base-pair) allele in Basques indicates that their genetic diversity for microsatellite DYS19 is around half that observed in Europeans, North Africans, and western Asians. The Y-Alu insertion (YAP+) was not detected in the Basque samples. This study attempts to throw some light on the importance of historically recent migratory movements, the main corridors of gene flow, and demographic sizes and their variations in shaping gene frequency patterns in contemporary human populations, particularly in the Mediterranean region. Historical processes may have had more significant effects on the genetic make-up of current human populations than those of prehistoric times.


Assuntos
Cromossomos Humanos Y/genética , Variação Genética , Repetições de Microssatélites/genética , Polimorfismo Genético , Sequências Repetitivas de Ácido Nucleico/genética , Alelos , Europa (Continente) , França , Frequência do Gene , Humanos , Masculino , Cadeias de Markov , Espanha , População Branca/genética
18.
J Econ Entomol ; 93(2): 374-9, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10826188

RESUMO

The relationship between damage by citrus leafminer, Phyllocnistis citrella Stainton, and 'Tahiti' lime yield were investigated in a 15-yr-old and a 5-yr-old lime orchard. Citrus leafminer population densities were controlled by insecticide applications of abamectin plus FC 435 oil, abamectin plus FC435 oil plus imidacloprid, and methomyl. The control was not treated. To ensure adequate citrus leafminer densities, adult citrus leafminer were periodically released in the experimental plots during fall and winter. For the 15-yr-old trees, the least amount of leaf area damage occurred in the abamectin plus FC 435 oil plus imidacloprid (1.9%) and the abamectin plus FC435 oil (2.3%) treatments compared with the control treatment (10-21%). In the 5-yr-old orchard, the least amount of leaf area damaged occurred in the abamectin plus FC 435 oil plus imidacloprid (0.4%) and the imidacloprid (0.1%) treatments compared with the control (20.85%). The percentage of leaf area damaged was linearly correlated with the average number of mines per leaf, average mine days, and cumulative mine days in both orchards. In both orchards, the percentage of leaf area damaged and cumulative mine days was linearly correlated with the number of fruit per tree and total fruit weight per tree. Calculating the economic injury levels indicated that 16-23% and 18-85% of leaf area damaged caused significant yield reductions in 15-yr-old and 5-yr-old trees, respectively.


Assuntos
Citrus/crescimento & desenvolvimento , Controle de Insetos , Mariposas , Animais , Imidazóis , Controle de Insetos/economia , Controle de Insetos/métodos , Inseticidas , Ivermectina/análogos & derivados , Metomil , Neonicotinoides , Nitrocompostos , Densidade Demográfica
19.
Am J Drug Alcohol Abuse ; 26(1): 97-112, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10718166

RESUMO

Substance abuse treatment studies frequently include subjects from different ethnic and racial groups, but many investigations limit the examination of race and ethnicity to the use of nominal labels. This approach reveals little about the social or psychological significance of racial and ethnic group membership to the subjects of study or about the potential effects of these factors on substance-involved behaviors. In this study, a principal components analysis (PCA) with varimax rotation was conducted on the 50-item long form of the Racial Identity Attitude Scale (RIAS) (1) in a sample of 294 African-American men in treatment for cocaine dependence. The RIAS was developed to measure attitudes about race and racial status among blacks, but it has not been utilized widely in substance abuse research. Our findings provide evidence for the structural validity of this instrument in this sample of substance abusers. We discuss how recent advances in racial identity theory and its measurement may provide an important avenue for understanding the psychological consequences of racial group membership and for examining the potential effects of these factors on treatment response in studies of substance misuse.


Assuntos
Negro ou Afro-Americano/psicologia , Transtornos Relacionados ao Uso de Cocaína/reabilitação , Identificação Social , Adolescente , Adulto , Transtornos Relacionados ao Uso de Cocaína/psicologia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Psicoterapia/métodos , Resultado do Tratamento
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