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1.
Plant Biotechnol J ; 21(12): 2525-2545, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37578160

RESUMO

Plant leaf senescence, caused by multiple internal and environmental factors, has an important impact on agricultural production. The lectin receptor-like kinase (LecRLK) family members participate in plant development and responses to biotic and abiotic stresses, but their roles in regulating leaf senescence remain elusive. Here, we identify and characterize a rice premature withered leaf 1 (pwl1) mutant, which exhibits premature leaf senescence throughout the plant life cycle. The pwl1 mutant displayed withered and whitish leaf tips, decreased chlorophyll content, and accelerated chloroplast degradation. Map-based cloning revealed an amino acid substitution (Gly412Arg) in LOC_Os03g62180 (PWL1) was responsible for the phenotypes of pwl1. The expression of PWL1 was detected in all tissues, but predominantly in tillering and mature leaves. PWL1 encodes a G-type LecRLK with active kinase and autophosphorylation activities. PWL1 is localized to the plasma membrane and can self-associate, mainly mediated by the plasminogen-apple-nematode (PAN) domain. Substitution of the PAN domain significantly diminished the self-interaction of PWL1. Moreover, the pwl1 mutant showed enhanced reactive oxygen species (ROS) accumulation, cell death, and severe DNA fragmentation. RNA sequencing analysis revealed that PWL1 was involved in the regulation of multiple biological processes, like carbon metabolism, ribosome, and peroxisome pathways. Meanwhile, interfering of biological processes induced by the PWL1 mutation also enhanced heat sensitivity and resistance to bacterial blight and bacterial leaf streak with excessive accumulation of ROS and impaired chloroplast development in rice. Natural variation analysis indicated more variations in indica varieties, and the vast majority of japonica varieties harbour the PWL1Hap1 allele. Together, our results suggest that PWL1, a member of LecRLKs, exerts multiple roles in regulating plant growth and development, heat-tolerance, and resistance to bacterial pathogens.


Assuntos
Oryza , Termotolerância , Xanthomonas , Espécies Reativas de Oxigênio/metabolismo , Oryza/metabolismo , Senescência Vegetal , Lectinas , Folhas de Planta/genética , Folhas de Planta/metabolismo , Regulação da Expressão Gênica de Plantas/genética , Proteínas de Plantas/metabolismo
2.
Int J Mol Sci ; 23(12)2022 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-35742990

RESUMO

Bacterial blight (BB) and bacterial leaf streak (BLS), caused by phytopathogenic bacteria Xanthomonas oryzae pv. oryzae (Xoo) and Xanthomonas oryzae pv. oryzicola (Xoc), respectively, are the most serious bacterial diseases of rice, while blast, caused by Magnaporthe oryzae (M. oryzae), is the most devastating fungal disease in rice. Generating broad-spectrum resistance to these diseases is one of the key approaches for the sustainable production of rice. Executor (E) genes are a unique type of plant resistance (R) genes, which can specifically trap transcription activator-like effectors (TALEs) of pathogens and trigger an intense defense reaction characterized by a hypersensitive response in the host. This strong resistance is a result of programed cell death induced by the E gene expression that is only activated upon the binding of a TALE to the effector-binding element (EBE) located in the E gene promoter during the pathogen infection. Our previous studies revealed that the E gene Xa23 has the broadest and highest resistance to BB. To investigate whether the Xa23-mediated resistance is efficient against Xanthomonas oryzae pv. oryzicola (Xoc), the causal agent of BLS, we generated a new version of Xa23, designated as Xa23p1.0, to specifically trap the conserved TALEs from multiple Xoc strains. The results showed that the Xa23p1.0 confers broad resistance against both BB and BLS in rice. Moreover, our further experiment on the Xa23p1.0 transgenic plants firstly demonstrated that the E-gene-mediated defensive reaction is also effective against M. oryzae, the causal agent of the most devastating fungal disease in rice. Our current work provides a new strategy to exploit the full potential of the E-gene-mediated disease resistance in rice.


Assuntos
Oryza , Xanthomonas , Resistência à Doença/genética , Expressão Ectópica do Gene , Oryza/metabolismo , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Efetores Semelhantes a Ativadores de Transcrição/metabolismo , Xanthomonas/genética
3.
Opt Express ; 24(23): 26715-26721, 2016 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-27857402

RESUMO

In this paper, a spectral model by incorporating SRS effect is proposed and established, which is feasible for analyzing the SRS effect both in high-power fiber oscillator and master oscillator power amplifier (MOPA) system. The theoretical results show that the SRS effect is tightly related to the bandwidths of the fiber Bragg gratings (FBGs) and it can be efficiently suppressed by optimizing the bandwidth of the FBGs. Besides, the established theoretical model is also feasible for analyzing the influence of seed power on the SRS effect. The theoretical predictions agree well with the previous experimental results.

4.
Anal Biochem ; 440(1): 18-22, 2013 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-23660014

RESUMO

We report a biosensor based on surface plasmon resonance (SPR) for the selective detection of maize chlorotic mottle virus (MCMV). 11-Mercaptoundecanoic acid was applied on a gold surface to form a self-assembled monolayer, and a layer of anti-MCMV antibody was crosslinked on the surface for specific recognition of MCMV. The effects of coupling reaction time and antibody concentration on detection sensitivity were studied. The coverage mass change is a function of the concentration of MCMV with a dynamic range from 1 to 1000 ppb. The detection limit is approximately 1 ppb, which is approximately two orders of magnitude higher than that of the existing enzyme-linked immunosorbent assay (ELISA) method. The developed SPR sensor showed highly specific recognition for both purified MCMV and crude extracts from real-world samples.


Assuntos
Técnicas Biossensoriais/métodos , Ácidos Graxos/análise , Compostos de Sulfidrila/análise , Ressonância de Plasmônio de Superfície/métodos , Tombusviridae/isolamento & purificação , Zea mays/virologia , Ensaio de Imunoadsorção Enzimática , Sensibilidade e Especificidade
5.
Issues Ment Health Nurs ; 34(7): 505-13, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23875552

RESUMO

Self-silencing theory suggests that women ignore their own feelings and needs to attend to the desires of others. However, the impact of such self-silencing on physical activity behavior is unknown. This study examined the degree of self-silencing among a group of highly educated and relatively affluent African American women and the strength of self-silencing as a predictor of physical activity. The mean total self-silencing score for participants was 71.46. Overall, women reported spending approximately 193 min per week engaged in physical activity but only 36% met current recommendations for aerobic physical activity. Self-silencing did not predict physical activity behavior.


Assuntos
Altruísmo , Negro ou Afro-Americano/psicologia , Emoções , Exercício Físico/psicologia , Identidade de Gênero , Atividade Motora , Apego ao Objeto , Autocuidado/psicologia , Responsabilidade Social , Adulto , Feminino , Comportamentos Relacionados com a Saúde/etnologia , Humanos , Estilo de Vida/etnologia , Pessoa de Meia-Idade , North Carolina , Qualidade de Vida/psicologia , Fatores de Risco , Autoimagem , Inquéritos e Questionários
6.
Materials (Basel) ; 15(19)2022 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-36234380

RESUMO

The objective of the present work is to evaluate the influence of material color on mechanical properties of fused deposition modeling (FDM) parts. The performance of the products is evaluated by testing eight different colors of acrylonitrile butadiene styrene (ABS) and polylactic acid (PLA) material in terms of tensile strength, compressive strength, and flexural strength. The analysis of data shows a significant difference in mechanical characteristics of prints depending on filament color. For different colors, these three strengths almost follow the same rising and falling tendency. In order to explore the relationship between mechanical strengths and filament colors, the color-mixing theory and the least-squares method are adopted to fit the best ratio coefficients of different color combinations. Results are presented showing that the strength value (e.g., tensile) of the mixed color can be evaluated through that of primary colors by fitting the other strength (e.g., compressive or flexural). It is shown that the predicted value is always no more than 7% error compared with the actual strength, in spite of two-color or three-color mixtures. An additional confirmation test with seven colored PLA filaments from different suppliers was conducted to focus on the extensibility. The outcomes show the maximum fitting errors of strengths for mixed colors in all cases are within 5%, proving the effectiveness and applicability of this predicted approach. This study can bring a detailed analysis that enables better estimation of the function of material color and contributes to improving the property of FDM printed products for consumers by choosing the suitable filament color.

7.
Micromachines (Basel) ; 13(4)2022 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-35457856

RESUMO

Due to the availability of materials and low cost for production, fused deposition modeling is becoming the most widely used additive manufacturing (AM) technology. However, the reasonable choice of process parameters for FDM is a significant task that directly affects the performance of the printed part. Therefore, it is necessary to investigate the influences of various process parameters on the quality characteristics of the components. The objectives of this study are to thoroughly review the current state of research that characterizes, estimates the effects of process parameters on mechanical properties, and summarizes the conclusions of existing works. In addition, some general issues of the presented research are summarized, and the need for future development is also emphasized. Finally, the research proposes several areas that deserve further study in this field.

8.
Front Plant Sci ; 13: 918673, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35693165

RESUMO

Transmembrane kinases (TMKs) play important roles in plant growth and signaling cascades of phytohormones. However, its function in the regulation of early leaf senescence (ELS) of plants remains unknown. Here, we report the molecular cloning and functional characterization of the WATER-SOAKED SPOT1 gene which encodes a protein belongs to the TMK family and controls chloroplast development and leaf senescence in rice (Oryza sativa L.). The water-soaked spot1 (oswss1) mutant displays water-soaked spots which subsequently developed into necrotic symptoms at the tillering stage. Moreover, oswss1 exhibits slightly rolled leaves with irregular epidermal cells, decreased chlorophyll contents, and defective stomata and chloroplasts as compared with the wild type. Map-based cloning revealed that OsWSS1 encodes transmembrane kinase TMK1. Genetic complementary experiments verified that a Leu396Pro amino acid substitution, residing in the highly conserved region of leucine-rich repeat (LRR) domain, was responsible for the phenotypes of oswss1. OsWSS1 was constitutively expressed in all tissues and its encoded protein is localized to the plasma membrane. Mutation of OsWSS1 led to hyper-accumulation of reactive oxygen species (ROS), more severe DNA fragmentation, and cell death than that of the wild-type control. In addition, we found that the expression of senescence-associated genes (SAGs) was significantly higher, while the expression of genes associated with chloroplast development and photosynthesis was significantly downregulated in oswss1 as compared with the wild type. Taken together, our results demonstrated that OsWSS1, a member of TMKs, plays a vital role in the regulation of ROS homeostasis, chloroplast development, and leaf senescence in rice.

9.
Eur J Pharm Sci ; 160: 105758, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33588044

RESUMO

OBJECTIVE: The bioavailability of conventional eye drops is very low due to different physiological barriers. Commercial latanoprost (LAT) eye drops (Xalatan®) need to be refrigerated and protected from light. The purpose of this study was to develop novel LAT eye drops to improve ocular bioavailability and stability. METHODS: Ophthalmic suspension containing LAT/γ-cyclodextrin (γCD) aggregates was designed and the preparation process was sufficiently studied. The prepared formulations were evaluated for pH, viscosity, osmolality, particle size, entrapment efficiency and in vitro release study. In vitro permeability study using Human Corneal Epithelial Cells and in vivo studies on rabbits were also performed. RESULTS: LAT/γCD aggregates were formed and confirmed by scanning electron microscopy. LAT/γCD eye drops showed obvious sustained release profiles and were more stable than Xalatan®. In vitro corneal permeation study indicated LAT/γCD eye drops had no significant cytotoxicity and had higher cell permeability. In vivo precorneal retention study showed AUC0-6 h, Cmax, and mean residence time (MRT) of LAT/γCD eye drops were 3.98, 2.12, and 2.07 times higher than those of Xalatan®, respectively. In vivo ocular distribution study revealed that AUC0-24 h, Cmax, and MRT for latanoprost acid in aqueous humor exhibited 2.60-fold, 1.36-fold, and 1.99-fold increase in LAT/γCD eye drops group than those of Xalatan® group, respectively. CONCLUSION: Cyclodextrin microaggregate suspension eye drops represent a potential strategy for enhanced bioavailability and stability of LAT.


Assuntos
Ciclodextrinas , Animais , Disponibilidade Biológica , Latanoprosta , Soluções Oftálmicas , Coelhos , Solubilidade
10.
Front Plant Sci ; 12: 641300, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33833770

RESUMO

Lesion mimic mutants (LMMs) are ideal materials for studying programmed cell death and defense response in plants. Here we report investigations on two LMMs (msl-1 and msl-2) from the indica rice cultivar JG30 treated by ethyl methyl sulfone. Both of the mutants showed similar mosaic spot lesions at seedling stage, but they displayed different phenotypes along with development of the plants. At tillering stage, larger orange spots appeared on leaves of msl-2, while only small reddish-brown spots exhibit on leaves of msl-1. At heading stage, the msl-2 plants were completely dead, while the msl-1 plants were still alive even if showed apparent premature senility. For both the mutants, the mosaic spot lesion formation was induced by light; DAB and trypan blue staining showed a large amount of hydrogen peroxide accumulated at the lesion sites, accompanied by a large number of cell death. Consequently, reactive oxygen species were enriched in leaves of the mutants; SOD and CAT activities in the scavenging enzyme system were decreased compared with the wild type. In addition, degraded chloroplasts, decreased photosynthetic pigment content, down-regulated expression of genes associated with chloroplast synthesis/photosynthesis and up-regulated expression of genes related to senescence were detected in the mutants, but the abnormality of msl-2 was more serious than that of msl-1 in general. Genetic analysis and map-based cloning revealed that the lesion mimic and premature senescence traits of both the mutants were controlled by recessive mutated alleles of the SL (Sekiguchi lesion) gene, which encodes the CYP71P1 protein belonging to cytochrome P450 monooxygenase family. The difference of mutation sites and mutation types (SNP-caused single amino acid change and SNP-caused early termination of translation) led to the different phenotypes in severity between msl-1 and msl-2. Taken together, this work revealed that the CYP71P1 is involved in regulation of both premature senescence and cell death in rice, and its different mutation sites and mutation types could cause different phenotypes in terms of severity.

11.
EPMA J ; 10(2): 101-108, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31258815

RESUMO

BACKGROUND: Selective reporting of results in published case-control studies has been widely suspected, but little comprehensive information on selective reporting is available with regard to case-control studies. We aimed to evaluate the concordance of findings between publications and the protocols of case-control studies and to assess the level of selective reporting of results in case-control studies. METHODS: The databases of Embase, Medline, Scopus, and Web of Science were searched to identify case-control study protocols published between January 1, 1990 and December 31, 2017. The numbers and characteristics of predefined exposures (or factors) were extracted from the protocols. The reported and unreported factors were both collected from the published studies and protocols. The frequency of selective reporting of results were estimated by identifying the discrepancies of factors between the protocols and the published studies. Study sample size and the extent of selective reporting of factors were measured by a Spearman correlation analysis. RESULTS: Fourteen protocols with 24 published studies and 159 factors were identified, of which eight protocols (57.1%) had discrepancies between the publications and protocols. The prevalence of incomplete reporting in published case-control studies was 42.9% (6/14), with participant characteristics, anthropometric and laboratory measurement variables more likely to be unreported. A total of 16,835 cases and 56,049 controls were recruited in the 14 protocols of case-control studies (sample size ranges from 428 to 52,596 per study). Sample size had no statistical significance with selective reporting of results (P > 0.05). CONCLUSION: The study protocols should be publicly available prior to the completion of case-control studies so that the potential bias can be assessed by the readers. Our findings highlight the need for investigators, peer reviewers, and readers to exercise increased awareness and scrutiny due to the undesirable practice of selective reporting of results in medical sciences causing the loss of potentially important information, thus impacting quality of personalized attitude in healthcare in the context of the predictive, preventive, and personalized medicine.

12.
J Subst Abuse Treat ; 34(2): 192-201, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17512159

RESUMO

Waiting time is a contemporary reality of many drug abuse treatment programs, resulting in substantial problems for substance users and society. Individual and system factors that influence waiting time are diverse and may vary at different points in the treatment continuum. This study assessed waiting time preceding clinical assessment at a centralized intake unit and during the period after the assessment but before treatment entry. The present study included 577 substance abusers who were enrolled in a large clinical trial of two brief treatment interventions in a midsize metropolitan area in Ohio. Bivariate analyses identified individual and system factors that influenced preassessment and postassessment waiting time, as well as total wait to treatment services. Multivariate analyses demonstrated that longer wait time for an assessment is influenced by being court referred, less belief in having a substance abuse problem, and less desire for change. A shorter wait to actually enter treatment is predicted by having a case manager, being more ready for treatment, and having less severe employment and alcohol problems. The different influences present during the two waiting periods suggest that assessment and treatment programs need to implement system changes and entry enhancement interventions that are specific to the needs of substance abusers at each waiting period.


Assuntos
Centros de Tratamento de Abuso de Substâncias/organização & administração , Transtornos Relacionados ao Uso de Substâncias/reabilitação , Listas de Espera , Adolescente , Adulto , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Ohio , Admissão do Paciente , Índice de Gravidade de Doença , Fatores de Tempo
13.
J Drug Issues ; 37(2): 321-340, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-18167519

RESUMO

The goal of the present study was to identify the dimensions present in items representing internal barriers to substance abuse treatment and to test their invariance across gender, ethnic, and age groups. Twenty items from the Barriers to Treatment Inventory (BTI) were used to assess the structure and nature of the internal treatment barriers of 518 clients presenting to a central intake unit for a substance abuse assessment. Exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) revealed that a five factor model provided the best fit to the data. Internal treatment barriers were best described by five dimensions: absence of problem, negative social support, fear of treatment, privacy concerns, and committed lifestyle. Extending the confirmatory factor analysis to test multi-group invariance, there were some differences in measurement and structural relations among the internal barrier dimensions across gender, ethnic, and age groups. However, the lack of invariance was small and practically insubstantial. The findings led to the conclusion that the theoretical constructs measured by the five internal barrier dimensions are equivalent across important characteristics in this population.

14.
Materials (Basel) ; 10(3)2017 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-28772620

RESUMO

Based on PVDF (piezoelectric sensing techniques), this paper attempts to study the propagation law of shock waves in brittle materials during the process of three-wavelength laser irradiation of polysilicon, and discusses the formation mechanism of thermal shock failure. The experimental results show that the vapor pressure effect and the plasma pressure effect in the process of pulsed laser irradiation lead to the splashing of high temperature and high density melt. With the decrease of the laser wavelength, the laser breakdown threshold decreases and the shock wave is weakened. Because of the pressure effect of the laser shock, the brittle fracture zone is at the edge of the irradiated area. The surface tension gradient and surface shear wave caused by the surface wave are the result of coherent coupling between optical and thermodynamics. The average propagation velocity of laser shock wave in polysilicon is 8.47 × 103 m/s, and the experiment has reached the conclusion that the laser shock wave pressure peak exponentially distributes attenuation in the polysilicon.

15.
J Subst Abuse Treat ; 30(3): 227-35, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16616167

RESUMO

The 59-item Barriers to Treatment Inventory (BTI) was administered to 312 substance abusers at a centralized intake unit following assessment but before treatment entry to assess their views on barriers to treatment. Factor analysis identified 25 items in 7 well-defined latent constructs: Absence of Problem, Negative Social Support, Fear of Treatment, Privacy Concerns, Time Conflict, Poor Treatment Availability, and Admission Difficulty. The factorial structure of the barriers is consistent with the findings of other studies that asked substance abusers about barriers to treatment and is conceptually compatible with Andersen's model of health care utilization. Factors were moderately to highly correlated, suggesting that they interact with one another. Selected characteristics were generally not predictive of barrier factors. Overall, results indicate that the BTI has good content validity and is a reliable instrument for assessing barriers to drug treatment. The potential utility of the BTI in assessment settings is discussed.


Assuntos
Centros de Tratamento de Abuso de Substâncias/estatística & dados numéricos , Transtornos Relacionados ao Uso de Substâncias/reabilitação , Adolescente , Adulto , Interpretação Estatística de Dados , Negação em Psicologia , Emprego , Análise Fatorial , Medo , Feminino , Acessibilidade aos Serviços de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Admissão do Paciente , Privacidade , Apoio Social , Fatores Socioeconômicos , Transtornos Relacionados ao Uso de Substâncias/psicologia , Inquéritos e Questionários
16.
Food Chem ; 156: 184-9, 2014 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-24629956

RESUMO

Transgenic maize plant expressing high phytase activity has been reported and approved by Chinese government in 2009. Here, we report a highly specific loop-mediated isothermal amplification (LAMP) method to detect the phytase gene in the GMO maize. The LAMP reaction takes less than 20min and the amplification is visible without gel electrophoresis. The detection sensitivity of the LAMP method is about 30 copies of phytase genomic DNA, which is 33.3 times greater than the conventional PCR method with gel electrophoresis. The quantitative detection results showed that the LAMP method has a good linear correlation between the DNA copy number and the associated Tt values over a large dynamic range of template concentration from 6×10(1) to 6×10(7) copies, with a quantification limit of 60 copies. Therefore, the LAMP method is visual, faster, and more sensitive, and does not need special equipment compared to traditional PCR technique, which is very useful for field tests and fast screening of GMO feeds.


Assuntos
6-Fitase/química , Técnicas de Amplificação de Ácido Nucleico/métodos , Organismos Geneticamente Modificados/metabolismo , Plantas Geneticamente Modificadas/genética , Zea mays/genética , Reação em Cadeia da Polimerase/métodos
17.
Subst Abus ; 29(1): 43-54, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19042318

RESUMO

The goal of the present study was to identify the multidimensional factor structure of external barriers to substance abuse treatment and test its invariance across gender, ethnic, and age groups in a sample of 518 substance abusers assessed at a centralized intake unit. Exploratory (EFA) and confirmatory factor analyses (CFA) demonstrated a well-defined multidimensional factor structure of highly differentiated external barrier factors: time conflict, treatment accessibility, treatment entry difficulty, and financial problems. Furthermore, multi-group CFA tests were used to test equivalencies of the measurement and structural models. The statistical fit results supported the invariance of the ethnic groups. Although there were some gender and age differences in measurement and structural relations among the external barrier facets, the model fit indices results provided support for the invariance of both measurement and structural models. The findings suggest that it would be reasonable to consider the pattern of factor loadings and structure relations as invariant across gender, ethnic, and age groups.


Assuntos
Análise Fatorial , Serviços de Saúde Mental/provisão & distribuição , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Transtornos Relacionados ao Uso de Substâncias/reabilitação , Adolescente , Adulto , Distribuição por Idade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Distribuição por Sexo
18.
Subst Abus ; 28(1): 11-23, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19274847

RESUMO

The goal of this study was to more fully understand readiness for treatment in a pre-treatment sample of 446 substance abusers. Structural Equation Modeling (SEM) was used to: (1) examine the relationships between readiness factors identified in the Pre-Treatment Readiness Scale; and (2) identify the effects of predisposing, illness, and inhibiting determinants on the factors. As with in-treatment samples, Problem Recognition was found to influence Treatment Readiness, although through a different intervening factor, Desire for Change rather than Desire for Help. A fourth factor, Treatment Reluctance, was also influenced by the Desire for Change factor. Fixed characteristics such as age and gender had minimal influences on readiness factors, as did inhibiting characteristics that reflected recent functioning. Illness characteristics including drug severity and perceived treatment barriers had a more robust influence on readiness factors. This study provides an increased understanding of readiness for treatment among pre-treatment substance abusers and also supported the construct validity of the Pre-Treatment Readiness Scale.


Assuntos
Atitude Frente a Saúde , Motivação , Transtornos Relacionados ao Uso de Substâncias/reabilitação , Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Meio Social , Apoio Social , Inquéritos e Questionários , Fatores de Tempo , Adulto Jovem
19.
J Adolesc ; 27(2): 165-79, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15023516

RESUMO

Using data from the Longitudinal Study of American Youth (LSAY), we aimed to determine the causal ordering between mathematics anxiety and mathematics achievement. Results of structural equation modelling showed that, across the entire junior and senior high school, prior low mathematics achievement significantly related to later high mathematics anxiety, but prior high mathematics anxiety hardly related to later low mathematics achievement. Mathematics achievement was more reliably stable from year to year than mathematics anxiety. There were statistically significant gender differences in the causal ordering between mathematics anxiety and mathematics achievement. Prior low mathematics achievement significantly related to later high mathematics anxiety for boys across the entire junior and senior high school but for girls at critical transition points only. Mathematics anxiety was more reliably stable from year to year among girls than among boys.


Assuntos
Ansiedade , Escolaridade , Matemática , Feminino , Humanos , Estudos Longitudinais , Masculino , Estados Unidos
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