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1.
Rev Sci Tech ; 36(1): 115-124, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28926022

RESUMO

Animal disease outbreaks generate a range of economic and non-economic impacts. While a significant number of research studies have estimated the effects of various diseases in a variety of contexts, examining the differential impacts and implications associated with the introduction of a novel disease into a developing country, as opposed to a developed one, is a rich area for further research. In this paper, the authors highlight some of the key dimensions and implications associated with the impacts of new diseases, how they differ in different contexts, and their implications for public policy.


La survenue de foyers de maladies animales entraîne des effets divers, de nature économique et non économique. Si l'estimation de l'impact de nombreuses maladies dans différents contextes a fait l'objet de très nombreuses études, l'évaluation différentielle de l'impact de l'introduction d'une maladie nouvelle dans un pays en développement et de ses conséquences, par opposition à ce qu'ils seraient dans un pays développé, constitue un domaine de recherche au riche potentiel largement inexploré. Les auteurs mettent en avant les dimensions et conséquences majeures de l'impact des maladies nouvelles et en soulignent les spécificités selon les contextes ainsi que leurs conséquences en termes de politiques publiques.


Los brotes de enfermedades animales traen consigo una serie de consecuencias de orden económico y no económico. Si bien ha habido numerosas investigaciones destinadas a evaluar los efectos de varias enfermedades en distintos contextos, el estudio del impacto y las repercusiones diferenciales que se siguen de la introducción de una nueva enfermedad en un país en desarrollo, por oposición a un país desarrollado, constituye un prometedor ámbito de investigación para el futuro. Los autores destacan algunas de las principales dimensiones y repercusiones ligadas a las consecuencias de nuevas enfermedades y examinan cómo difieren en función del contexto y cómo repercuten en las políticas públicas.


Assuntos
Doenças dos Animais/economia , Países Desenvolvidos/economia , Países em Desenvolvimento/economia , Doenças dos Animais/classificação , Animais
2.
Animal ; 17(12): 101023, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37981450

RESUMO

Welfare assessment of dairy cows by in-person farm visits provides only a snapshot of welfare and is time-consuming and costly. Possible solutions to reduce the need for in-person assessments would be to exploit sensor data and other routinely collected on-farm records. The aim of this study was to develop an algorithm to classify dairy cow welfare based on sensors (accelerometer and/or milk meter) and farm records (e.g. days in milk, lactation number). In total, 318 cows from six commercial farms located in Finland, Italy and Spain (two farms each) were enrolled for a pilot study lasting 135 days. During this time, cows were routinely scored using 14 animal-based measures of good feeding, health and housing based on the Welfare Quality® (WQ®) protocol. WQ® measures were evaluated daily or approximately every 45 days, using disease treatments from farm records and on-farm visits, respectively. WQ® measures were supplemented with daily temperature-humidity index to account for heat stress. The severity and duration of each welfare measure were evaluated, and the final welfare index was obtained by summing up the values for each cow on each pilot study day, and stratifying the result into three classes: good, moderate and poor welfare. For model building, a machine-learning (ML) algorithm based on gradient-boosted trees (XGBoost) was applied. Two model versions were tested: (1) a global model tested on unseen herd, and (2) a herd-specific model tested on unseen part of the data from the same herd. The version (1) served as an example on the model performance on a herd not previsited by the evaluator, while version (2) resembled a custom-made solution requiring in-person welfare evaluation for model training. Our results indicated that the global model had a low performance with average sensitivity and specificity of 0.44 and 0.68, respectively. For the herd-specific version, the model performance was higher reaching an average of 0.64 sensitivity and 0.80 specificity. The highest classification performance was obtained for cows in poor welfare, followed by cows in good and moderate welfare (balanced accuracy of 0.77, 0.71 and 0.68, respectively). Since the global model had low classification accuracy, the use of the developed model as a stand-alone system based solely on sensor data is infeasible, and a combination of in-person and sensor-based welfare evaluation would be preferable for a reliable welfare assessment. ML-based solutions, even with fair discriminative abilities, have the potential to enhance dairy welfare monitoring.


Assuntos
Bem-Estar do Animal , Indústria de Laticínios , Animais , Bovinos , Feminino , Indústria de Laticínios/métodos , Fazendas , Lactação , Leite , Projetos Piloto
3.
R Soc Open Sci ; 9(6): 220093, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35706659

RESUMO

We explore the sensitivity of several core-level spectroscopic methods to the underlying atomistic structure by using the water molecule as our test system. We first define a metric that measures the magnitude of spectral change as a function of the structure, which allows for identifying structural regions with high spectral sensitivity. We then apply machine-learning-emulator-based decomposition of the structural parameter space for maximal explained spectral variance, first on overall spectral profile and then on chosen integrated regions of interest therein. The presented method recovers more spectral variance than partial least-squares fitting and the observed behaviour is well in line with the aforementioned metric for spectral sensitivity. The analysis method is able to independently identify spectroscopically dominant degrees of freedom, and to quantify their effect and significance.

4.
Animal ; 14(10): 2178-2186, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32349838

RESUMO

In order to reduce antimicrobial use in pig production, the consequences of insufficient biosecurity and welfare problems need to be known. This study aimed to investigate associations between the number of antimicrobial treatments per fattening pig, and biosecurity, indicators for animal welfare as well as the prevalence of lesions at slaughter. The data used in this study were extracted from the pig health and welfare classification system (Sikava), which gathers data on medicine usage, meat inspection, animal welfare and the condition of farm buildings from over 95% of pig production in Finland. The data were registered during years from 2011 to 2013. Upon antimicrobial prescription, information on the number of fattening pigs treated and the main reason for treatment was recorded. In addition, at least 4 times per year, pig farms registered in Sikava were visited by the farm veterinarian who assessed, among other things, biosecurity and indicators for animal welfare (air quality, condition of facilities, cleanliness, enrichment and stocking density). Finally, data from slaughterhouse inspections were collected (number of carcasses with joint infection, abscesses, lung lesions, pleurisy and liver lesions). For analysis, these datasets were aggregated at the farm level to a quarter of a year. During the studied period, the mean number of antimicrobial treatments per fattening pig per 3 months was equal to 0.09. The main reasons for antimicrobial treatments were musculoskeletal diseases, tail biting and respiratory disorders (42, 33 and 12% of diagnoses, respectively). The meat inspection scoring indicated that as much as 14.7% of all pigs had pleurisy, 5.3% liver lesions and 4.1% abscesses. A standard zero-inflated negative binomial model was used to identify factors associated with the number of antimicrobial treatments per pig. The count of antimicrobial treatments per pig increased with the size of a farm. Regardless of prevalence of lesions, farms with poor drinking equipment, insufficient enrichment and a combination of poor condition of pens and high stocking density were associated with an increased number of antimicrobial treatments for musculoskeletal diseases per pig. Problems with stocking density and enrichment were associated with the number of antimicrobial treatments for tail biting, although these results depended on prevalence of joint infections. Problems with air quality and the combination of poor cleanliness and poor condition of facilities were associated with increased number of antimicrobial treatments due to respiratory diseases. This study suggests that by improving biosecurity and welfare at pig farms, antimicrobial use can be reduced.


Assuntos
Anti-Infecciosos , Doenças dos Suínos , Criação de Animais Domésticos , Bem-Estar do Animal , Animais , Anti-Infecciosos/uso terapêutico , Fazendas , Finlândia , Padrões de Referência , Suínos , Doenças dos Suínos/tratamento farmacológico , Doenças dos Suínos/epidemiologia , Doenças dos Suínos/prevenção & controle
5.
Prev Vet Med ; 84(3-4): 194-212, 2008 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-18207589

RESUMO

Rapid structural change and concentration of pig production in regions with most intensive production has raised concerns about whether the risk of large-scale disease losses has increased in Finland. This paper examines the pig industry's losses due to classical swine fever (CSF) epidemics. The work is based on economic and epidemiological models providing insights to the consequences of epidemics to infected and uninfected farms, government and meat processing. The economic analysis was carried out by use of a sector model, which simulated the recovery of pig production, starting from the recognition of the disease in the country and ending at a steady-state market equilibrium about 12 years later. The model explicitly took into account profit-maximising behaviour of producers and the effects of decrease in export demand. Epidemiological evidence suggests that under the current spatially diversified structure of Finnish pig farming and related industries, the probability of a severe disease epidemic counting dozens of infected farms is small. Even for epidemics considered large in Finland (5-33 infected farms) combined with a major reduction in export demand, the median loss was simulated to be only euro19.2 million. The majority of these losses were due to loss of exports corresponding almost 20% of pig meat production in Finland. While the current structure of pig farming in Finland incurs higher production costs than the most intensive structures in Europe, it also seems to decrease the probability of 'catastrophic' economic losses. The results suggest that the response of export markets and the number of uninfected farms affected by preventive measures are critical to the magnitude of losses, as they can amplify losses even if only few farms become infected.


Assuntos
Criação de Animais Domésticos/economia , Peste Suína Clássica/economia , Comércio/economia , Indústria de Embalagem de Carne/economia , Carne/economia , Animais , Peste Suína Clássica/epidemiologia , Simulação por Computador , Surtos de Doenças/economia , Surtos de Doenças/veterinária , Finlândia/epidemiologia , Carne/microbiologia , Modelos Econométricos , Método de Monte Carlo , Suínos
6.
Animal ; 10(4): 687-99, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26522665

RESUMO

To limit tail biting incidence, most pig producers in Europe tail dock their piglets. This is despite EU Council Directive 2008/120/EC banning routine tail docking and allowing it only as a last resort. The paper aims to understand what it takes to fulfil the intentions of the Directive by examining economic results of four management and housing scenarios, and by discussing their consequences for animal welfare in the light of legal and ethical considerations. The four scenarios compared are: 'Standard Docked', a conventional housing scenario with tail docking meeting the recommendations for Danish production (0.7 m2/pig); 'Standard Undocked', which is the same as 'Standard Docked' but with no tail docking, 'Efficient Undocked' and 'Enhanced Undocked', which have increased solid floor area (0.9 and 1.0 m2/pig, respectively) provision of loose manipulable materials (100 and 200 g/straw per pig per day) and no tail docking. A decision tree model based on data from Danish and Finnish pig production suggests that Standard Docked provides the highest economic gross margin with the least tail biting. Given our assumptions, Enhanced Undocked is the least economic, although Efficient Undocked is better economically and both result in a lower incidence of tail biting than Standard Undocked but higher than Standard Docked. For a pig, being bitten is worse for welfare (repeated pain, risk of infections) than being docked, but to compare welfare consequences at a farm level means considering the number of affected pigs. Because of the high levels of biting in Standard Undocked, it has on average inferior welfare to Standard Docked, whereas the comparison of Standard Docked and Enhanced (or Efficient) Undocked is more difficult. In Enhanced (or Efficient) Undocked, more pigs than in Standard Docked suffer from being tail bitten, whereas all the pigs avoid the acute pain of docking endured by the pigs in Standard Docked. We illustrate and discuss this ethical balance using numbers derived from the above-mentioned data. We discuss our results in the light of the EU Directive and its adoption and enforcement by Member States. Widespread use of tail docking seems to be accepted, mainly because the alternative steps that producers are required to take before resorting to it are not specified in detail. By tail docking, producers are acting in their own best interests. We suggest that for the practice of tail docking to be terminated in a way that benefits animal welfare, changes in the way pigs are housed and managed may first be required.


Assuntos
Bem-Estar do Animal/normas , União Europeia , Abrigo para Animais/legislação & jurisprudência , Suínos , Bem-Estar do Animal/legislação & jurisprudência , Animais , Mordeduras e Picadas , Europa (Continente) , Abrigo para Animais/normas , Incidência
7.
Biochim Biophys Acta ; 1480(1-2): 191-200, 2000 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-11004563

RESUMO

The genes rdmB and rdmC of Streptomyces purpurascens encoding aclacinomycin modifying enzymes RdmB and RdmC were expressed in Streptomyces lividans TK24. In contrast to the earlier suggestion that RdmC may be an esterase that causes the removal of the carbomethoxy group from the 10 position of aclacinomycins, RdmC functions as an aclacinomycin methyl esterase and catalyzes the removal of the methoxy group from the C-15 position of aclacinomycin T producing 15-demethoxyaclacinomycin T. RdmB acts upon C-10 of 15-demethoxyaclacinomycin T and is able to remove the carboxylic group from the C-10 position. It functions also as an aclacinomycin-10-hydroxylase being able to add a hydroxyl group at the same, C-10 position in vitro. Aclacinomycin methyl esterase was purified to apparent homogeneity from S. lividans carrying the rdmC and aclacinomycin-10-hydroxylase as a glutathione S-transferase fusion construct from Escherichia coli carrying the rdmB gene, respectively. Aclacinomycin methyl esterase functions as a monomer and aclacinomycin-10-hydroxylase as a tetramer. Aclacinomycin methyl esterase has an exceptionally high temperature stability and has an apparent K(m) for aclacinomycin T of 15.5 microM. The introduction of rdmC and rdmB in a Streptomyces galilaeus mutant HO38 produced the same modifications of aclacinomycin T in vivo as aclacinomycin methyl esterase and aclacinomycin-10-hydroxylase in vitro.


Assuntos
Aclarubicina/análogos & derivados , Hidrolases de Éster Carboxílico/metabolismo , Oxigenases de Função Mista/metabolismo , Streptomyces/enzimologia , Aclarubicina/metabolismo , Sequência de Bases , Hidrolases de Éster Carboxílico/isolamento & purificação , Catálise , Primers do DNA , Oxigenases de Função Mista/isolamento & purificação
8.
Biochim Biophys Acta ; 1430(1): 57-64, 1999 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-10082933

RESUMO

Aklavinone-11-hydroxylase (RdmE) is a FAD monooxygenase participating in the biosynthesis of daunorubicin, doxorubicin and rhodomycins. The rdmE gene encodes an enzyme of 535 amino acids. The sequence of the Streptomyces purpurascens enzyme is similar to other Streptomyces aromatic polyketide hydroxylases. We overexpressed the gene in Streptomyces lividans and purified aklavinone-11-hydroxylase to apparent homogeneity with four chromatographic steps utilizing a kinetic photometric enzyme assay. The enzyme is active as the monomer with a molecular mass of 60 kDa; it hydroxylates aklavinone and other anthracyclinones. Aklavinone-11-hydroxylase can use both NADH and NADPH as coenzyme but it is slowly inactivated in the presence of NADH. The apparent Km for NADPH is 2 mM and for aklavinone 10 microM. The enzyme is inactivated in the presence of phenylglyoxal and 2,3-butanedione. NADPH protects against inactivation of aklavinone-11-hydroxylase by phenylglyoxal.


Assuntos
Hidrocarboneto de Aril Hidroxilases/isolamento & purificação , Streptomyces/enzimologia , Antraciclinas/farmacocinética , Hidrocarboneto de Aril Hidroxilases/antagonistas & inibidores , Hidrocarboneto de Aril Hidroxilases/química , Biotransformação , Genes Bacterianos , Cinética , NADP , Fenilglioxal , Streptomyces/genética , Temperatura
9.
J Anim Sci ; 93(8): 4161-71, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26440196

RESUMO

The selection of animals for improved performance affects the profitability of pig fattening and has environmental consequences. The goal of this paper was to examine how changes in genetic and market parameters impact the biophysical (feeding patterns, timing of slaughter, nitrogen excretion) and economic (return per pig space unit) results describing pig fattening in a Finnish farm. The analysis can be viewed as focusing on terminal line breeding goals. An integrated model using recursive stochastic dynamic programming and a biological pig growth model was used to estimate biophysical results and economic values. Combining these models allowed us to provide more accurate estimates for the value of genetic improvement and, thus, provide better feedback to animal breeding programs than the traditional approach, which is based on fixed management patterns. Besides the benchmark scenario, the results were simulated for 5 other scenarios. In each scenario, genotype was improved regarding daily growth potential, carcass lean meat content, or the parameters of the Gompertz growth curve (maturing rate [], adult weight of protein [α], and adult weight of lipid mass []). The change in each parameter was equal to approximately 1 SD genetic improvement (ceteris paribus). Increasing , , daily growth potential, or carcass lean meat content increased the return on pig space unit by €12.60, €7.60, €4.10, or €2.90 per year, respectively, whereas an increase in decreased the return by €3.10. The genetic improvement in and resulted in the highest decrease in nitrogen excretion calculated in total or per kilogram of carcass gain but only under the optimal feeding pattern. Simulated changes in the Gompertz growth function parameters imply greater changes in ADG and lean meat content than changes in scenarios focusing on improving ADG and lean meat content directly. The economic value of genetic improvements as well as the quantity of nitrogen excreted during the fattening period largely depends on feeding. Improved genotypes can require changes in pig management pattern. Estimating the influence of the genotype on the nitrogen excretion without considering changes in the management pattern can result in flawed conclusions. To improve overall economic performance and to decrease the environmental footprint of fattening pig production, the pig producer can adjust the herd management pattern according to the pigs' genetics.


Assuntos
Suínos/genética , Suínos/fisiologia , Aumento de Peso/genética , Aumento de Peso/fisiologia , Criação de Animais Domésticos , Animais , Composição Corporal/genética , Meio Ambiente , Finlândia , Genótipo , Modelos Biológicos , Nitrogênio/metabolismo
10.
Neuroscience ; 302: 174-203, 2015 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-25242643

RESUMO

Peripheral nerves regenerate following injury due to the effective activation of the intrinsic growth capacity of the neurons and the formation of a permissive pathway for outgrowth due to Wallerian degeneration (WD). WD and subsequent regeneration are significantly influenced by various immune cells and the cytokines they secrete. Although macrophages have long been known to play a vital role in the degenerative process, recent work has pointed to their importance in influencing the regenerative capacity of peripheral neurons. In this review, we focus on the various immune cells, cytokines, and chemokines that make regeneration possible in the peripheral nervous system, with specific attention placed on the role macrophages play in this process.


Assuntos
Degeneração Neural/etiologia , Degeneração Neural/imunologia , Regeneração Nervosa/fisiologia , Neuroimunomodulação/fisiologia , Doenças do Sistema Nervoso Periférico/complicações , Animais , Citocinas/genética , Citocinas/metabolismo , Humanos
11.
Gene ; 50(1-3): 41-53, 1986.
Artigo em Inglês | MEDLINE | ID: mdl-3582984

RESUMO

We describe a new approach to differential hybridization, designed to identify cDNA clones representing rare mRNA species. Duplicate filters carrying a library of cDNA from phorbolmyristate acetate (PMA)-induced EL-4 cells in lambda gt11 were hybridized with high concentrations of unlabeled, cloned, single-stranded cDNA from induced and control EL-4 cells, respectively. Plaques binding single-stranded cDNA were revealed by a second round of hybridization with 35S-labeled DNA complementary to the vector moiety of the single-stranded cDNA. Plaques corresponding to PMA-induced mRNAs occurring at a level of about 1 part in 15,000 were isolated. We believe the method is at least ten times more sensitive than conventional differential hybridization.


Assuntos
Clonagem Molecular/métodos , DNA/genética , Hibridização de Ácido Nucleico , RNA Mensageiro/genética , Animais , DNA de Cadeia Simples/genética , Regulação da Expressão Gênica , Vetores Genéticos , Linfoma/genética , Camundongos
12.
Gene ; 93(1): 91-9, 1990 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-2227430

RESUMO

A fragment of DNA carrying the hitherto unisolated members of the cluster of genes (red) for biosynthesis of the red-pigmented antibiotic undecylprodigiosin of Streptomyces coelicolor A3(2) was isolated. This was done by cloning random fragments of S. coelicolor DNA into the closely related Streptomyces lividans 66 and recovering a clone that caused overproduction of undecylprodigiosin. The effect was probably due to the presence of the cloned redD gene, which functions as a positive regulator of the expression of the red cluster, activating the normally poorly expressed red genes of S. lividans. Two fragments from either end of the red cluster were cloned adjacent to each other on a low-copy-number Streptomyces vector. Double crossing-over occurring between these plasmid-borne sequences and the chromosomal copy of the same DNA in S. coelicolor led to isolation of the entire red cluster as a single cloned fragment. Isolation of antibiotic biosynthetic genes by the effects of an activator in a self-cloning experiment, and in vivo reconstitution of a large cluster of genes by homologous recombination, may turn out to be usefully generalizable procedures.


Assuntos
Prodigiosina/análogos & derivados , Streptomyces/genética , Clonagem Molecular , DNA Bacteriano/genética , Genes Bacterianos , Teste de Complementação Genética , Plasmídeos , Prodigiosina/biossíntese , Recombinação Genética , Mapeamento por Restrição
13.
Cortex ; 28(4): 537-54, 1992 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1282448

RESUMO

An extensive naming battery was administered to ten patients representing classical aphasia syndromes. The battery included traditional performance measures and error scoring, phonological cuing, multiple-choice tasks tapping semantic and phonological knowledge, and word repetition tests. Differences in the patients' performance profiles were interpreted as reflecting lexical-phonological, phoneme assembly or multiple deficits. The results suggest that the hypothesized naming deficits have complex relationships to classical aphasia syndromes.


Assuntos
Anomia/fisiopatologia , Afasia/fisiopatologia , Dano Encefálico Crônico/fisiopatologia , Adulto , Idoso , Anomia/diagnóstico , Anomia/psicologia , Afasia/diagnóstico , Afasia/psicologia , Afasia de Broca/diagnóstico , Afasia de Broca/fisiopatologia , Afasia de Broca/psicologia , Afasia de Wernicke/diagnóstico , Afasia de Wernicke/fisiopatologia , Afasia de Wernicke/psicologia , Dano Encefálico Crônico/diagnóstico , Dano Encefálico Crônico/psicologia , Córtex Cerebral/fisiopatologia , Infarto Cerebral/diagnóstico , Infarto Cerebral/fisiopatologia , Infarto Cerebral/psicologia , Dominância Cerebral/fisiologia , Feminino , Humanos , Masculino , Rememoração Mental/fisiologia , Pessoa de Meia-Idade , Testes Neuropsicológicos , Reconhecimento Visual de Modelos/fisiologia , Semântica
14.
Cortex ; 24(4): 579-88, 1988 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-3219872

RESUMO

As convincing as the discussion presented by Elizabeth Bates, Angela Friederici and Beverly Wulfeck on grammatical morphology in aphasia in three languages may seem, we were at loss when trying to reconstruct the quantitative basis of their argumentation (see Bates et al., 1987, Grammatical morphology in aphasia: Evidence from three languages. Cortex, 23: 545-575). With the present notice we would like to lessen the possibility of reader misinterpretations that may easily confuse the thread of the argument of this article in the form in which it was originally presented.


Assuntos
Afasia de Broca/psicologia , Afasia de Wernicke/psicologia , Afasia/psicologia , Idioma , Humanos , Testes de Linguagem
15.
J Biomech ; 28(5): 555-66, 1995 May.
Artigo em Inglês | MEDLINE | ID: mdl-7775491

RESUMO

Patterns of load-sharing between the shoulder muscles during isometric flexion tasks were studied by using both a biomechanical shoulder model and electromyographic (EMG) recordings of ten subjects. The effect of changes in several model parameters and shoulder stiffness constraints on the predicted load-sharing patterns were studied, while the arm position, hand load and precision requirements of the tasks were varied. The results calculated using the model were, when compared to the EMG recordings, plausible predicting a high level of synergistic contraction of muscles of the shoulder muscles during flexion tasks. The trends of the model-predicted muscle forces corresponded well to the EMG recordings. At low hand load levels the increasing of the shoulder stiffness strongly increased the muscle force levels, thus increasing also the level of synergistic contraction of muscles. At higher load levels the increase in the muscle forces was not so high, because the model predicted a high level of simultaneous contraction of muscles already at a low level of shoulder stiffness. Cluster analysis of the EMG recordings revealed large inter-individual differences in the load distribution patterns during flexion tasks. The constraint angle of the glenohumeral joint contact force direction was found to be an important model parameter affecting both the predicted forces and the maximum force production ability of the shoulder.


Assuntos
Contração Isométrica/fisiologia , Músculo Esquelético/fisiologia , Ombro/fisiologia , Adulto , Algoritmos , Fenômenos Biomecânicos , Análise por Conglomerados , Elasticidade , Eletromiografia , Humanos , Masculino , Computação Matemática , Modelos Biológicos , Postura/fisiologia , Rotação , Suporte de Carga
16.
J Biomech ; 29(4): 451-60, 1996 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8964774

RESUMO

A static shoulder model including a novel muscular synergy principle for computing load sharing between the shoulder muscles is presented. This principle is feasible especially when analysing endurance-type activities. According to the principle, time elapsed from the start of the activity decreases the allowable muscle stress levels on the basis of the stress-endurance time curves of individual muscles. At low load levels the sum of the squared forces is minimized. At higher load levels the increase in the stress levels of individual muscles is counteracted in order to prevent fatigue. In the model the direction of the contact force in the glenohumeral joint is constrained. The stiffness of the shoulder can also be constrained to produce more muscular co-contraction in tasks with high precision demands.


Assuntos
Modelos Biológicos , Músculos/fisiologia , Ombro/fisiologia , Fenômenos Biomecânicos , Previsões , Humanos , Fatores de Tempo
17.
Brain Lang ; 68(1-2): 262-7, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10433768

RESUMO

A wug type of plural production task with Finnish-speaking 10- to 11-year-old normals and 10-year-old SLI children shows that formal transparency of affixation and the lexicality (real words vs pseudowords) of the stimuli affect the performance of both groups. Not unexpectedly, nontransparent pseudowords receive drastically low correctness rates among the SLI speakers. The failures of the SLI group corroborate the claim that they have not internalized the productive inflectional morphology involved in plural formation to the extent that their normal, age-matched peers have.


Assuntos
Transtornos da Linguagem/diagnóstico , Comportamento Verbal/fisiologia , Criança , Pré-Escolar , Humanos
18.
Brain Lang ; 61(1): 45-53, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9448930

RESUMO

The Finnish language is used here to enrich our conception of the dysprosody hypothesis of the output in Broca's agrammatism, i.e., of the claim that agrammatic speech is characterized by aberrant timing and intonation patterns. The native language of the two agrammatic aphasics of the present study places a high functional load on quantity (acoustically: timing/duration) in its phonology, as the short-long quantity opposition concerns both vowels and consonants. Moreover, the quantity opposition in Finnish is not local, i.e., syllable-internal as in many Germanic languages, because the phonetic quantity values are determined by a disyllabic sequence. In contrast to the high functional load of quantity in its lexical phonology, Finnish makes little, if any, grammatical use of intonation. In the present acoustic analyses it was noted that the two Broca's aphasics have preserved the disyllabically determined quantity oppositions, although the speech of the aphasics is characterized by long interword pauses, i.e., by syntactic dysprosody. In contrast to the asyntactic timing patterns, the declination line of intonation is retained in the output of the present aphasics in spite of the low grammatical value of intonation in the language. The present results further dispute the characterization of agrammatic speech output as being dysprosodic, or more specifically atemporal, as lexical quantity and syntactic tonal patterns can be retained in a speech mode that is replete with long interword pauses. More generally, the observations will corroborate the autonomy (modularity) of lexical and syntactic processes in oral language production.


Assuntos
Afasia de Broca/diagnóstico , Fonética , Adulto , Afasia de Broca/etiologia , Infarto Cerebral/complicações , Feminino , Finlândia , Humanos , Masculino , Pessoa de Meia-Idade
19.
Brain Lang ; 68(1-2): 158-64, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10433753

RESUMO

The present study focuses on a subtype of Finnish nouns that appear only as complements in idiomatic verb phrases. In addition to the idioms as their sole environment, these idiomatic isolates, as we call them, are typically frozen to a single case form. In two experiments, in a subjective rating task and a lexical decision task, the isolates are pitted against ordinary nouns and nouns that appear as frozen forms in idioms in addition to being ordinary, free words. The experiments show that the isolates, in spite of their defective syntactic and morphological properties, are processed like ordinary lexical items.


Assuntos
Vocabulário , Cognição/fisiologia , Finlândia , Humanos , Semântica , Comportamento Verbal
20.
Brain Lang ; 68(1-2): 340-6, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10433779

RESUMO

The present article investigates the influences of word-internal category information and linearity on the processing of morphologically complex words. Three sets of Finnish derived nouns consisting of a noun, adjective or verb stem, and a suffix were submitted to two on-line category decision tasks, where the subjects had to decide whether the word was a noun or a verb respectively. Both experiments show a stem-suffix category mismatch effect manifesting itself in prolonged reaction time latencies. Thus, the results indicate that the order of presentation and the word-internal structural information are intimately tied together also in the visual processing of morphological complex words.


Assuntos
Cognição/fisiologia , Vocabulário , Finlândia , Humanos , Percepção Visual/fisiologia
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