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1.
Plant Genome ; 14(3): e20155, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34596348

RESUMO

Plant phenotyping under field conditions plays an important role in agricultural research. Efficient and accurate high-throughput phenotyping strategies enable a better connection between genotype and phenotype. Unmanned aerial vehicle-based high-throughput phenotyping platforms (UAV-HTPPs) provide novel opportunities for large-scale proximal measurement of plant traits with high efficiency, high resolution, and low cost. The objective of this study was to use time series normalized difference vegetation index (NDVI) extracted from UAV-based multispectral imagery to characterize its pattern across development and conduct genetic dissection of NDVI in a large maize population. The time series NDVI data from the multispectral sensor were obtained at five time points across the growing season for 1,752 diverse maize accessions with a UAV-HTPP. Cluster analysis of the acquired measurements classified 1,752 maize accessions into two groups with distinct NDVI developmental trends. To capture the dynamics underlying these static observations, penalized-splines (P-splines) model was used to obtain genotype-specific curve parameters. Genome-wide association study (GWAS) using static NDVI values and curve parameters as phenotypic traits detected signals significantly associated with the traits. Additionally, GWAS using the projected NDVI values from the P-splines models revealed the dynamic change of genetic effects, indicating the role of gene-environment interplay in controlling NDVI across the growing season. Our results demonstrated the utility of ultra-high spatial resolution multispectral imagery, as that acquired using a UAV-based remote sensing, for genetic dissection of NDVI.


Assuntos
Tecnologia de Sensoriamento Remoto , Zea mays , Agricultura/métodos , Estudo de Associação Genômica Ampla , Tecnologia de Sensoriamento Remoto/métodos , Estações do Ano , Zea mays/genética
2.
J Geriatr Psychiatry Neurol ; 34(6): 528-554, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-32935611

RESUMO

The aim of this article was to systematically review the quality and efficacy of the current evidence for mindfulness-based interventions (MBIs) in patients with mild cognitive impairment (MCI), patients with dementia (PwD), and their caregivers. We identified 20 randomized controlled trials (RCTs) (11 for patients, 9 for caregivers) published in the last 15 years. Evidence suggested that MBIs are highly acceptable and credible treatments for patients with MCI, PwD and caregivers. Specifically, for PwD, the results indicated that the magnitude of post-treatment effects of MBIs are in the medium to large range for psychosocial outcomes, and in the small to medium range for cognitive functioning; however, treatment effects on dementia biomarkers were mixed, ranging from small to large, depending on the outcome measure. Findings also evidenced salutary effects of MBIs for caregivers of PwD, with post-treatment effects ranging from medium to large for caregiver stress and burden and large effects for quality of life, and mixed outcomes for cognitive functioning, with effects in the small to large range. However, confidence in these findings is relatively limited due to methodological limitations, especially in terms of poor consistency in intervention strategies, outcome measures, and other key criteria across studies. To better assess the value of MBIs for these populations and optimize treatment outcomes, we recommend further research with improved study methodology (e.g., multi-method assessment, universal criterion and outcome measures, use of active control groups, larger sample sizes, long-term follow-up) to replicate current findings and enhance our understanding of underlying treatment mechanisms of MBIs.


Assuntos
Disfunção Cognitiva , Demência , Atenção Plena , Cuidadores , Cognição , Disfunção Cognitiva/terapia , Demência/terapia , Humanos
3.
Med Probl Perform Art ; 35(1): 42-53, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32135004

RESUMO

AIMS: Objective information on embouchure muscle use in brass players is currently limited. This pilot study records and analyses embouchure muscle activity in trumpet players to identify typical patterns and to reveal how these can differ between playing tasks. METHODS: Activity in four embouchure muscles was recorded using surface electromyography in 7 conservatoire trumpet students and 3 elite professional trumpeters. Each played a set of simple exercises, tongued and slurred, including single notes of different pitch, upward and downward transitions between notes a fifth apart, arpeggios, and a short musical piece. RESULTS: Muscle activity was initiated 0.4-2.0 s before the beginning of a note. In some players this was at a higher level than needed to sustain the note, while in others it was not. Levels of activity in all muscles generally increased and decreased together during arpeggios, in line with changing pitch. The sound was terminated by an abrupt fall in muscle activity. In many players, transitions between notes a fifth apart required no change in muscle activity, though in others this was marked by a sharp increase or decrease. CONCLUSION: Though levels of muscle activity rose consistently over large pitch ranges, there was considerable variation in the degree to which this occurred over smaller intervals. Even among the 3 professional players, the embouchure muscle activity showed clear individual patterns, suggesting that high levels of performance can be achieved in different ways. Further investigations will be needed to clarify how embouchure activity changes with proficiency.


Assuntos
Música , Língua , Eletromiografia , Humanos , Projetos Piloto , Estudantes , Língua/fisiologia
4.
J Ment Health ; 29(4): 401-409, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31066599

RESUMO

Background: Adolescents attending Seventh-day Adventist schools (Adventist) in Australia tend to experience good health and exhibit better health behaviors than national norms, however few studies have investigated factors predicting their mental health.Aims: The aim of this study was to explore the complex network of factors that predict the mental health status (MHS) of adolescents attending Adventist schools in Australia.Methods: A survey instrument was used to collect data from 1527 secondary school students attending Adventist schools across Australia. Structural equation modeling was employed to examine concomitantly the direct and indirect effects of childhood experiences, present attitudes and selected health behaviors on MHS.Results: Childhood family dynamics had the strongest association with MHS (ßtotal = 0.33) followed by a sense of meaning and purpose (ßtotal = 0.27), perceived social misfit status (ßtotal = -0.19), and school academic performance (ßtotal = 0.18). Multi-group analysis found significant pathway differences in the model for gender with regards to the association of meaning and purpose, physical activity and sleep quantity with MHS.Conclusions: The outcomes of the study highlight the importance of early positive childhood family dynamics and the discovery of meaning and purpose during adolescence to promote positive mental health among adolescents.


Assuntos
Saúde Mental , Religião e Psicologia , Estudantes/psicologia , Adolescente , Austrália , Criança , Organizações Religiosas , Feminino , Humanos , Análise de Classes Latentes , Masculino , Protestantismo/psicologia , Instituições Acadêmicas
5.
Med Probl Perform Art ; 33(3): 183-190, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30204824

RESUMO

AIMS: Though ergonomic supports are widely used for many groups of instruments, they are rare for brass instruments, despite the instruments' considerable weight. Musculoskeletal injury and postural problems are common among this group, and so, both adult and young players are likely to benefit from supports that reduce the load placed on the body. This study assessed the effects on postural muscle activity of a recently developed range of supports (Ergobrass) that use a rod to transfer the weight of the instrument to a harness or to the chair or floor. METHODS: Twenty conservatoire students (mean age [SD], 20.9 ± 0.5 yrs) of the trumpet, french horn, or trombone used the supports while playing short brass studies, either sitting or standing. Surface electromyography recordings were made from key postural muscles, and their activity levels were compared with and without the support. RESULTS: Statistically significant reductions (typically 15-30%) were present in many of the muscles when using the supports, though in some players they were much larger. The number of muscles affected was least with the lightest instruments (the trumpet), with the effects mainly in the left deltoid and trapezius muscles. Reductions for the horn were bilateral, principally in biceps, pectoralis major, and deltoid; while in the trombone, they were confined to the left side (pectoralis major, posterior deltoid, and trapezius), as the right arm is in constant use to move the slide. CONCLUSIONS: The supports are effective in reducing postural muscle activity and may be of particular benefit to injured or young players.


Assuntos
Ergonomia/instrumentação , Músculo Esquelético/fisiologia , Doenças Musculoesqueléticas/prevenção & controle , Música , Doenças Profissionais/prevenção & controle , Postura/fisiologia , Extremidade Superior/fisiologia , Adaptação Fisiológica , Fenômenos Biomecânicos , Eletromiografia , Humanos , Doenças Musculoesqueléticas/fisiopatologia , Doenças Profissionais/fisiopatologia , Adulto Jovem
6.
BMC Public Health ; 18(1): 440, 2018 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-29615084

RESUMO

BACKGROUND: The factors shaping the health of the current generation of adolescents are multi-dimensional and complex. The purpose of this study was to explore the determinants of self-rated health (SRH) of adolescents attending a faith-based school system in Australia. METHODS: A total of 788 students attending 21 Seventh-day Adventist schools in Australia responded to a health and lifestyle survey that assessed SRH as well as potential determinants of SRH including the health outcomes mental health, vitality, body mass index (BMI), select health behaviors, social factors and personal demographics. Structural equation modeling was used to analyze the data and examine the direct and indirect effects of these factors on SRH. RESULTS: The structural model developed was a good fit with the data. The health outcome mental health had the strongest association with SRH (ß = 0.17). Several upstream variables were also associated with higher SRH ratings. The health behavior sleep hours had the strongest association with SRH (ßtotal = 0.178) followed by fruit/vegetable consumption (ßtotal = 0.144), physical activity (ßtotal = 0.135) and a vegetarian diet (ßtotal = 0.103). Of the demographic and social variables measured, adverse childhood experiences (ACEs) had the strongest association with SRH (ßtotal = - 0.125), negatively influencing SRH, and gender also associated with an increase in SRH (ßtotal = 0.092), with the influence of these factors being mediated through other variables in the model. CONCLUSIONS: This study presents a conceptual model that illustrates the complex network of factors concomitantly associated with SRH in adolescents. The outcomes of the study provide insights into the determinants of adolescent SRH which may inform priority areas for improving this construct.


Assuntos
Autoavaliação Diagnóstica , Comportamentos Relacionados com a Saúde , Nível de Saúde , Meio Social , Adolescente , Austrália , Criança , Feminino , Inquéritos Epidemiológicos , Humanos , Masculino , Modelos Teóricos , Protestantismo , Instituições Acadêmicas
7.
J Relig Health ; 57(3): 994-1009, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28913748

RESUMO

Students attending Seventh-day Adventist (Adventist) schools in Australia have been shown to have better health status and behaviours compared to secular norms, yet these schools cater for a high percentage of non-Adventist students. The purpose of this study was to investigate the influence of religious affiliation (Adventist/non-Adventist) on the health status and behaviours of students attending Adventist secondary schools in Australia. The sample included 1734 students who responded to a health and lifestyle survey that captured demographic details, self-reported height and weight, self-reported health status, mental health and select health behaviours. Students who identified themselves as Adventist reported significantly better health behaviours than the non-Adventist students in several behavioural domains, especially among the male students. However, this did not translate to a difference in health status. Further research is needed to understand the causal mechanisms responsible for the potential health advantage of Adventist students, which may include family or church religious influences.


Assuntos
Comportamento do Adolescente , Comportamentos Relacionados com a Saúde , Nível de Saúde , Protestantismo , Estudantes/psicologia , Adolescente , Austrália , Criança , Feminino , Humanos , Masculino , Instituições Acadêmicas
8.
J Sch Health ; 87(8): 630-637, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28691170

RESUMO

BACKGROUND: We examined the body mass index (BMI) of students attending Seventh-day Adventist (Adventist) schools in Australia in 2001 and 2012. METHODS: A total of 3069 students attending Adventist schools in Australia responded to a health and lifestyle survey in 2001 (N = 1335) and 2012 (N = 1734). The survey captured self-reported height and weight, demographics (age, sex, year level, religion), and select health behaviors. RESULTS: Compared with national norms, lower rates of overweight and obesity were observed in the study cohort, but higher rates of underweight. There was no change in the mean BMI of the students attending Adventist schools in Australia from 2001 to 2012. Regression analyses indicated that a lower BMI was associated with age, sex, more regularly eating breakfast, consuming less soft drink, and having a regular exercise program. The students reported a high consumption of fruits, vegetables, and whole grains compared with Australian national norms, and 29% claimed to be vegetarian. CONCLUSIONS: Students attending Adventist schools appear to have a lower prevalence of overweight and obesity than the secular population, but a higher prevalence of underweight. The mechanisms through which Adventist schools may influence student's BMI warrants further investigation.


Assuntos
Saúde do Adolescente/estatística & dados numéricos , Nível de Saúde , Estado Nutricional , Protestantismo , Adolescente , Fenômenos Fisiológicos da Nutrição do Adolescente , Austrália , Índice de Massa Corporal , Feminino , Humanos , Masculino , Obesidade Infantil/epidemiologia , Análise de Regressão
9.
Springerplus ; 5(1): 1521, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27652094

RESUMO

BACKGROUND: CRISPR-Cas9 genome editing and labeling has emerged as an important tool in biologic research, particularly in regards to potential transgenic and gene therapy applications. Delivery of CRISPR-Cas9 plasmids to target cells is typically done by non-viral methods (chemical, physical, and/or electrical), which are limited by low transfection efficiencies or with viral vectors, which are limited by safety and restricted volume size. In this work, a non-viral transfection technology, named lance array nanoinjection (LAN), utilizes a microfabricated silicon chip to physically and electrically deliver genetic material to large numbers of target cells. To demonstrate its utility, we used the CRISPR-Cas9 system to edit the genome of isogenic cells. Two variables related to the LAN process were tested which include the magnitude of current used during plasmid attraction to the silicon lance array (1.5, 4.5, or 6.0 mA) and the number of times cells were injected (one or three times). RESULTS: Results indicate that most successful genome editing occurred after injecting three times at a current control setting of 4.5 mA, reaching a median level of 93.77 % modification. Furthermore, we found that genome editing using LAN follows a non-linear injection-dose response, meaning samples injected three times had modification rates as high as nearly 12 times analogously treated single injected samples. CONCLUSIONS: These findings demonstrate the LAN's ability to deliver genetic material to cells and indicate that successful alteration of the genome is influenced by a serial injection method as well as the electrical current settings.

10.
Toxins (Basel) ; 7(4): 1065-78, 2015 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-25826055

RESUMO

Harmful algal blooms (HABs) degrade water quality and produce toxins. The spatial distribution of HAbs may change rapidly due to variations wind, water currents, and population dynamics. Risk assessments, based on traditional sampling methods, are hampered by the sparseness of water sample data points, and delays between sampling and the availability of results. There is a need for local risk assessment and risk management at the spatial and temporal resolution relevant to local human and animal interactions at specific sites and times. Small, unmanned aircraft systems can gather color-infrared reflectance data at appropriate spatial and temporal resolutions, with full control over data collection timing, and short intervals between data gathering and result availability. Data can be interpreted qualitatively, or by generating a blue normalized difference vegetation index (BNDVI) that is correlated with cyanobacterial biomass densities at the water surface, as estimated using a buoyant packed cell volume (BPCV). Correlations between BNDVI and BPCV follow a logarithmic model, with r(2)-values under field conditions from 0.77 to 0.87. These methods provide valuable information that is complimentary to risk assessment data derived from traditional risk assessment methods, and could help to improve risk management at the local level.


Assuntos
Proliferação Nociva de Algas , Tecnologia de Sensoriamento Remoto , Aeronaves , Água Doce , Luz , Microcystis , Medição de Risco/métodos , Análise Espacial , Qualidade da Água
11.
Springerplus ; 3: 210, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25279272

RESUMO

PURPOSE: The object of this study was to examine the effect of posture on breathing in brass players. Breathing when standing was compared with sitting erect on a flat, downward or upward sloping seat, or on a reclining seat. METHODS: Spirometry was used to measure aspects of lung function. Muscle activity and respiratory movements during different playing tasks were recorded using electromyography and inductive plethysmography. RESULTS: Only sitting in a reclining position produced statistically significantly lower values for VC, FVC, FEV1, PEF than standing. When players were asked to produce a note of maximum duration, only a downward sloping seat caused a significant change (an 11% reduction) compared to standing. When seated, the abdominal component of respiratory movement was significantly higher during these long notes than when standing, though maximum activity in abdominal wall muscles was significantly reduced (by 32-44%). On a downward sloping seat, muscle activity was significantly higher (9%) than on a flat seat. Tongued and untongued sforzando notes recruited significantly less abdominal muscle activity (33-67%) when sitting than when standing. When playing a trumpet study, abdominal muscle activity was significantly reduced on a downward sloping seat (by 32%) and on a flat seat (by 40%) in comparison to standing. Muscle activity in the two sitting positions were not significantly different. CONCLUSION: Though brass players are often told to "sit as if standing", abdominal muscle activity is always significantly reduced when sitting on a flat or downward sloping seat, however when greater respiratory effort is required, activity on downward sloping seats may rise closer to that of standing.

12.
Work ; 40(3): 317-24, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22045538

RESUMO

Professional musicians require a disciplined and balanced regime of practise and performance to enable them to cope with the physical challenges of their chosen instrument and to reduce the risk of work- related injury. If practise or performance strategies are suddenly changed, permanent damage may occur even in a player with a mature, well-established technique. The trombone presents unique physical challenges which are heightened by recent developments in instrumental design as well as by orchestral working conditions. This study presents the experiences of a professional orchestral trombonist who worked as a principal player in a UK orchestra until his performing career was cut short by a performance related injury. His personal approach to practise is discussed in the context of the physical and professional challenges associated with contemporary orchestral practices. The case study demonstrates the importance of considering the interplay between psychological and physical factors in the development and treatment of injury in musicians.


Assuntos
Música , Traumatismos Ocupacionais/prevenção & controle , Postura/fisiologia , Lesões do Ombro , Feminino , Humanos , Masculino , Síndromes de Compressão Nervosa/etiologia , Síndromes de Compressão Nervosa/prevenção & controle , Traumatismos Ocupacionais/etiologia , Estresse Fisiológico/fisiologia , Reino Unido
14.
Proc Natl Acad Sci U S A ; 102(42): 15144-8, 2005 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-16217022

RESUMO

Future drought is projected to occur under warmer temperature conditions as climate change progresses, referred to here as global-change-type drought, yet quantitative assessments of the triggers and potential extent of drought-induced vegetation die-off remain pivotal uncertainties in assessing climate-change impacts. Of particular concern is regional-scale mortality of overstory trees, which rapidly alters ecosystem type, associated ecosystem properties, and land surface conditions for decades. Here, we quantify regional-scale vegetation die-off across southwestern North American woodlands in 2002-2003 in response to drought and associated bark beetle infestations. At an intensively studied site within the region, we quantified that after 15 months of depleted soil water content, >90% of the dominant, overstory tree species (Pinus edulis, a piñon) died. The die-off was reflected in changes in a remotely sensed index of vegetation greenness (Normalized Difference Vegetation Index), not only at the intensively studied site but also across the region, extending over 12,000 km2 or more; aerial and field surveys confirmed the general extent of the die-off. Notably, the recent drought was warmer than the previous subcontinental drought of the 1950s. The limited, available observations suggest that die-off from the recent drought was more extensive than that from the previous drought, extending into wetter sites within the tree species' distribution. Our results quantify a trigger leading to rapid, drought-induced die-off of overstory woody plants at subcontinental scale and highlight the potential for such die-off to be more severe and extensive for future global-change-type drought under warmer conditions.


Assuntos
Clima , Desastres , Temperatura Alta , Árvores/fisiologia , Ecossistema , Sudoeste dos Estados Unidos
15.
Ambio ; 34(6): 462-9, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16201218

RESUMO

The recent rise in Brazilian soybean production has generated concern among the environmental community and some authors that natural tropical environments of the Amazon Basin are being converted to soybean fields. Proponents of soybean production counter that soybeans represent a viable agricultural commodity for the region; environmental concern is unwarranted, because new soybean fields are replacing already deforested or otherwise transformed lands. Both arguments have been made without comprehensive study and measure of land-use/land-cover (LULC) in areas undergoing expansion of soybean production. This case study, conducted in the municipality of Vilhena, Rondônia, Brazil, in the southwestern Amazon Basin, uses remote sensing to evaluate the LULC accompanying this municipality's large growth in soybean production from 1996 to 2001. Forests are being converted for soybean production, but most of the production increase appears attributable to slight expansion of already existing fields, conversion of already deforested land, and higher yields.


Assuntos
Produtos Agrícolas , Ecossistema , Agricultura Florestal , Glycine max , Brasil
16.
J Environ Qual ; 31(3): 846-59, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12026088

RESUMO

We explored relationships of water quality parameters with landscape pattern metrics (LPMs), land use-land cover (LULC) proportions, and the advanced very high resolution radiometer (AVHRR) normalized difference vegetation index (NDVI) or NDVI-derived metrics. Stream sites (271) in Nebraska, Kansas, and Missouri were sampled for water quality parameters, the index of biotic integrity, and a habitat index in either 1994 or 1995. Although a combination of LPMs (interspersion and juxtaposition index, patch density, and percent forest) within Ozark Highlands watersheds explained >60% of the variation in levels of nitrite-nitrate nitrogen and conductivity, in most cases the LPMs were not significantly correlated with the stream data. Several problems using landscape pattern metrics were noted: small watersheds having only one or two patches, collinearity with LULC data, and counterintuitive or inconsistent results that resulted from basic differences in land use-land cover patterns among ecoregions or from other factors determining water quality. The amount of variation explained in water quality parameters using multiple regression models that combined LULC and LPMs was generally lower than that from NDVI or vegetation phenology metrics derived from time-series NDVI data. A comparison of LPMs and NDVI indicated that NDVI had greater promise for monitoring landscapes for stream conditions within the study area.


Assuntos
Agricultura , Ecossistema , Monitoramento Ambiental/métodos , Comunicações Via Satélite , Poluentes Químicos da Água/análise , Água Doce , Geografia , Humanos , Kansas , Missouri , Nebraska , Análise de Regressão
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