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1.
Cogn Res Princ Implic ; 9(1): 22, 2024 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-38616234

RESUMO

In sport, coaches often explicitly provide athletes with stable contextual information related to opponent action preferences to enhance anticipation performance. This information can be dependent on, or independent of, dynamic contextual information that only emerges during the sequence of play (e.g. opponent positioning). The interdependency between contextual information sources, and the associated cognitive demands of integrating information sources during anticipation, has not yet been systematically examined. We used a temporal occlusion paradigm to alter the reliability of contextual and kinematic information during the early, mid- and final phases of a two-versus-two soccer anticipation task. A dual-task paradigm was incorporated to investigate the impact of task load on skilled soccer players' ability to integrate information and update their judgements in each phase. Across conditions, participants received no contextual information (control) or stable contextual information (opponent preferences) that was dependent on, or independent of, dynamic contextual information (opponent positioning). As predicted, participants used reliable contextual and kinematic information to enhance anticipation. Further exploratory analysis suggested that increased task load detrimentally affected anticipation accuracy but only when both reliable contextual and kinematic information were available for integration in the final phase. This effect was observed irrespective of whether the stable contextual information was dependent on, or independent of, dynamic contextual information. Findings suggest that updating anticipatory judgements in the final phase of a sequence of play based on the integration of reliable contextual and kinematic information requires cognitive resources.


Assuntos
Atletas , Futebol , Humanos , Reprodutibilidade dos Testes , Fonte de Informação , Julgamento
2.
Sci Med Footb ; : 1-8, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38530231

RESUMO

Researchers investigating expertise in soccer goalkeepers have overwhelmingly focused on anticipating penalty kicks and identifying kinematic cues that are used to anticipate action outcomes. In this study, we took a novel approach to exploring 'game reading' skills in soccer goalkeepers. Specifically, we investigated whether and by what point during an attacking sequence in open play, elite goalkeepers can identify the opposition shot taker, a skill that is likely to facilitate organisation of the defensive line and interception of forward creative attacking passes. We used a moving window temporal occlusion paradigm to present elite, sub-elite, and amateur goalkeepers with 11-vs-11 attacking sequences that were divided into progressive segments. After viewing each segment, participants identified the player they thought would shoot at goal at the end of the attacking sequence. Elite goalkeepers identified the opposition shot taker earlier and more accurately than sub-elite and amateur participants. Findings suggest that elite goalkeeping is underpinned not only by anticipation of action outcomes but also game-reading skill that enables identification of the player most likely to carry out those actions.

3.
Eur J Appl Physiol ; 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38532177

RESUMO

Prior studies suggest resistance exercise as a potential form of motor learning due to task-specific corticospinal responses observed in single sessions of motor skill and resistance training. While existing literature primarily focuses on upper limb muscles, revealing a task-dependent nature in eliciting corticospinal responses, our aim was to investigate such responses after a single session of lower limb motor skill and resistance training. Twelve participants engaged in a visuomotor force tracking task, self-paced knee extensions, and a control task. Corticospinal, spinal, and neuromuscular responses were measured using transcranial magnetic stimulation (TMS) and peripheral nerve stimulation (PNS). Assessments occurred at baseline, immediately post, and at 30-min intervals over two hours. Force steadiness significantly improved in the visuomotor task (P < 0.001). Significant fixed-effects emerged between conditions for corticospinal excitability, corticospinal inhibition, and spinal excitability (all P < 0.001). Lower limb motor skill training resulted in a greater corticospinal excitability compared to resistance training (mean difference [MD] = 35%, P < 0.001) and control (MD; 37%, P < 0.001). Motor skill training resulted in a lower corticospinal inhibition compared to control (MD; - 10%, P < 0.001) and resistance training (MD; - 9%, P < 0.001). Spinal excitability was lower following motor skill training compared to control (MD; - 28%, P < 0.001). No significant fixed effect of Time or Time*Condition interactions were observed. Our findings highlight task-dependent corticospinal responses in lower limb motor skill training, offering insights for neurorehabilitation program design.

4.
Sci Rep ; 14(1): 3364, 2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38337002

RESUMO

In this study, we tested the theory of angles that was proposed almost a century ago by the tennis player Henri Cochet. This theory proposes that expert tennis players should position themselves on the bisector of the angle of the opponent's possibilities in order to optimize shot return, suggesting a geometric occupation of the court relative to the opponent's affordances; namely what he/she is capable of doing. We tested this hypothesis by analysing player and ball positioning data from professional tennis matches recorded with a Hawk-Eye system. We compared this hypothesis with two alternative computational and probabilistic hypotheses which would consist in positioning oneself on the average or the median of the shots usually played from a given location. The results show that expert tennis players apply the principles of the theory of angles and thus confirm Henri Cochet's intuition. That is, for lateral court positioning, a geometric strategy is deemed optimal by expert players. It also appears that the more experienced the players are, the more precise their application of this strategy becomes.

5.
Ir J Med Sci ; 193(1): 533-537, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37462894

RESUMO

BACKGROUND: Mandibular angle fractures (MAF) have a recognized complexity of treatment and an increased risk of incurring complications. METHODS: This retrospective study included 45 consecutive patients who were diagnosed with an isolated MAF and no other facial fractures. The average age was 27.3 (SD = 7.7). RESULTS: A comparatively low rate of complications (11.1%) and a low rate of reoperation (1.8%) are reported, along with a significant role of smoking in complications (p = 0.022). A non-significant association was noted between complications, male gender and assault as an aetiological factor. CONCLUSIONS: Review of the data from this study confirms that complication rates for patients attending the National Maxillofacial Unit are similar to or better than that of international studies. An overview of the aetiology of fracture complications is included.


Assuntos
Fixação Interna de Fraturas , Fraturas Mandibulares , Humanos , Masculino , Adulto , Estudos Retrospectivos , Complicações Pós-Operatórias/etiologia , Fraturas Mandibulares/complicações , Fraturas Mandibulares/cirurgia , Demografia
6.
Cleft Palate Craniofac J ; : 10556656231191384, 2023 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-37533341

RESUMO

OBJECTIVE: Identification of patient factors influencing velopharyngeal function for speech following initial cleft palate repair. DESIGN: A literature search of relevant databases from inception until 2018 was performed using medical subject headings and keywords related to cleft palate, palatoplasty and speech assessment. Following three stage screening data extraction was performed. SETTING: Systematic review and meta-analysis of relevant literature. PATIENTS/PARTICIPANTS: Three hundred and eighty-three studies met the inclusion criteria, comprising data on 47 658 participants. INTERVENTIONS: Individuals undergoing initial palatoplasty. MAIN OUTCOME MEASURES: Studies including participants undergoing initial cleft palate repair where the frequency of secondary speech surgery and/or velopharyngeal function for speech was recorded. RESULTS: Patient factors reported included cleft phenotype (95% studies), biological sex (64%), syndrome diagnosis (44%), hearing loss (28%), developmental delay (16%), Robin Sequence (16%) and 22q11.2 microdeletion syndrome (11%). Meta-analysis provided strong evidence that rates of secondary surgery and velopharyngeal dysfunction varied according to cleft phenotype (Veau I best outcomes, Veau IV worst outcomes), Robin Sequence and syndrome diagnosis. There was no evidence that biological sex was associated with worse outcomes. Many studies were poor quality with minimal follow-up. CONCLUSIONS: Meta-analysis demonstrated the association of certain patient factors with speech outcome, however the quality of the evidence was low. Uniform, prospective, multi-centre documentation of preoperative characteristics and speech outcomes is required to characterise risk factors for post-palatoplasty velopharyngeal insufficiency for speech. SYSTEMATIC REVIEW REGISTRATION: Registered with PROSPERO CRD42017051624.

7.
Ir J Med Sci ; 192(6): 3169-3173, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37150759

RESUMO

BACKGROUND: There are limited studies examining alcohol consumption in Gaelic Athletic Association (GAA) players. In a previous paper, we reported excess alcohol consumption, alcohol-related harms and binge drinking amongst elite GAA players. In that survey, the players were provided with an opportunity to provide comments on alcohol. This current study analyses these comments. AIMS: The aim of this study was to provide a qualitative analysis of elite GAA players opinions on alcohol consumption, harms, behaviours and culture. METHODS: An anonymous, web-based e-questionnaire was distributed to all registered adult elite (inter-county) GAA players. This analysed demographics, alcohol consumption, alcohol culture and alcohol-related harms. This paper is a thematic analysis of the players comments on alcohol in the GAA. RESULTS: Seven hundred seventy-three of 3592 (21%) players responded. One hundred fifty-two respondents (21%) commented in the free text section of the survey regarding alcohol. One hundred eleven comments (73%) were suitable for analysis. Relevant themes were a pattern of abstinence and bingeing (n = 44), excess alcohol consumption (n = 40) and drinking bans contributing to a binge drinking culture (n = 37). There was a mixed attitude to alcohol sponsorship. CONCLUSION: These data show players recognise intermittent binge drinking with periods of abstinence and alcohol-related harms. Further initiatives regarding alcohol harm reduction merit consideration including prohibition of alcohol sponsorship, similar to the GAA's ban on gambling.


Assuntos
Consumo Excessivo de Bebidas Alcoólicas , Esportes , Adulto , Humanos , Consumo Excessivo de Bebidas Alcoólicas/epidemiologia , Inquéritos e Questionários , Atletas , Etanol , Consumo de Bebidas Alcoólicas/epidemiologia
8.
Exp Brain Res ; 241(3): 807-824, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36740653

RESUMO

Motor skill training alters the human nervous system; however, lower limb motor tasks have been less researched compared to upper limb tasks. This meta-analysis with best evidence synthesis aimed to determine the cortical and subcortical responses that occur following lower limb motor skill training, and whether these responses are accompanied by improvements in motor performance. Following a literature search that adhered to the PRISMA guidelines, data were extracted and analysed from six studies (n = 172) for the meta-analysis, and 11 studies (n = 257) were assessed for the best evidence synthesis. Pooled data indicated that lower limb motor skill training increased motor performance, with a standardised mean difference (SMD) of 1.09 being observed. However, lower limb motor skill training had no effect on corticospinal excitability (CSE), Hoffmann's reflex (H-reflex) or muscle compound action potential (MMAX) amplitude. The best evidence synthesis found strong evidence for improved motor performance and reduced short-interval cortical inhibition (SICI) following lower limb motor skill training, with conflicting evidence towards the modulation of CSE. Taken together, this review highlights the need for further investigation on how motor skill training performed with the lower limb musculature can modulate corticospinal responses. This will also help us to better understand whether these neuronal measures are underpinning mechanisms that support an improvement in motor performance.


Assuntos
Destreza Motora , Treinamento Resistido , Humanos , Destreza Motora/fisiologia , Tratos Piramidais/fisiologia , Músculo Esquelético/fisiologia , Extremidade Superior , Potencial Evocado Motor/fisiologia , Estimulação Magnética Transcraniana
9.
Sci Rep ; 13(1): 823, 2023 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-36646773

RESUMO

Problem gambling levels amongst elite sportspeople are above populational baseline. We assess gambling in an elite Irish sporting population. An anonymous web-based questionnaire including the validated Problem Gambling Severity Index was distributed. Univariate and multivariate analyses were performed to evaluate predictors of moderate/high risk gambling. 608 players (mean age 24) were included. Seventy nine percent of respondents were current gamblers and 6% problem gamblers. Amongst high-risk gamblers, significantly more were male (100% vs 76%, p = 0.003), fewer completed university (52% vs 69%, p = 0.024), and more were smokers (48% vs 24%, p = 0.002). They were also more likely to avail of free online gambling offers (90% vs 44%, p < 0.001), gamble with teammates (52% vs 21%, p < 0.001) and have placed their first bet before age 16 (41% vs 19%, p = 0.003). In multivariate analysis, moderate/high risk gambling was associated with: male gender (OR = 8.9 [1.1-69], p = 0.035), no 3rd level education (OR = 2.5 [1.4-5.0], p = 0.002), free online gambling use (OR = 4.3 [2.1-5.3], p < 0.001), gambling with teammates (OR = 3.0 [1.7-5.3], p < 0.001), and being under 18 at first bet (OR = 2.0 [1.1-3.3], p = 0.013). This study shows a harmful gambling culture amongst elite Irish athletes. Male gender, lower educational status, free online gambling use, gambling with teammates and first bet at less than age 18 were associated with moderate/high risk gambling. These groups may benefit from targeted interventions.


Assuntos
Jogo de Azar , Humanos , Masculino , Adulto Jovem , Adulto , Adolescente , Feminino , Jogo de Azar/epidemiologia , Escolaridade , Análise Multivariada , Inquéritos e Questionários , Atletas
10.
Eur J Sport Sci ; 23(10): 2049-2058, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36426512

RESUMO

External focus of attention has been shown to promote more automatic motor control, yielding better performance and more efficient technique, than an internal focus. However, most research has used closed-skill tasks in novices. The extent to which the reported pattern of findings generalises to more complex, time-constrained tasks requires further investigation. In this study, we investigated the effect of attentional focus instructions on performance and technique in an open-skill task in skilled performers. Thirteen skilled cricket batters batted from a ball projector in four conditions, receiving instructions to focus on the movement of their hands (internal focus), the movement of their bat (proximal external focus), the flight of the ball (distal external focus), or no instruction (control). Performance and technique were measured by quality of bat-ball contacts and step length/knee flexion, respectively, whilst playing straight drives. Compared to external focus and control conditions, focusing internally yielded significantly worse batting performance and shorter step lengths, with the largest effects observed between internal and distal external focus conditions. Quality of bat-ball contact data suggested that participants' ability to protect the wicket (as evidenced by more miss/edge shots) was more negatively affected by focusing internally than their ability to play shots to score runs (as evidenced by fewer good bat-ball contacts). Findings suggest that, for skilled performance of open-skill tasks, a distal external focus yields more effective performance and technique compared with focusing internally. Findings highlight the need for further research on attentional focus effects between different skills within specific sports.Highlights A distal external focus of attention enhances performance and technique of skilled cricket batters compared with an internal focus.Providing skilled batters with no instructions yields similar performance benefits to distal external focus instructions.Focusing internally differentially negatively affects skilled cricket batters depending on the strategic intention of the shot being played (e.g. protecting the wicket vs attempting to score runs).


Assuntos
Destreza Motora , Esportes , Humanos , Atenção , Movimento , Extremidade Superior
11.
Ir J Med Sci ; 191(5): 2091-2098, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34699001

RESUMO

BACKGROUND: Sportspeople are more prone to binge drink than their peers. AIMS: We aimed to assess alcohol consumption, harms and behaviours in an elite Irish sporting population (Gaelic footballers and hurlers). METHODS: An anonymous web-based questionnaire (demographics, alcohol consumption, culture and related harms) was administered to all elite players. The AUDIT-C questionnaire (frequency, quantity of alcohol consumption and frequency of binge drinking) was used to assess for adverse alcohol use. Univariate and multivariate analyses assessed for predictors of adverse alcohol use. RESULTS: 717 players (mean age 24 years) were analysed. The majority of patients were male (75%), unmarried (93%) and had completed university (67%). 96% were current drinkers. Players consumed more alcohol during the off-season (median 20 versus 8 standard drinks in 28 days) compared to the elite season. Amongst current drinkers, 73% exhibit adverse alcohol use, 93% reported binge drinking and 65% an alcohol related harm in the past year. Most players would turn to family (36%) or friends (21%) for help. There were significant associations between monthly bingeing (OR 18.4), smoking (OR 3.3), generally drinking in public (OR 3.2), current gambling (OR 2.3), male gender (OR 2.1), an alcohol harm in the past year (OR 1.9) and adverse alcohol use. In contrast, co-habiting with a partner (OR 0.5) was protective. CONCLUSIONS: Excess alcohol consumption, alcohol related harms and binge drinking are prevalent in an elite sporting population, particularly during the off-season. Specific strategies are required to reduce alcohol related harms, particularly amongst high-risk groups during the off-season.


Assuntos
Alcoolismo , Consumo Excessivo de Bebidas Alcoólicas , Esportes , Adulto , Consumo de Bebidas Alcoólicas/efeitos adversos , Consumo de Bebidas Alcoólicas/epidemiologia , Alcoolismo/epidemiologia , Consumo Excessivo de Bebidas Alcoólicas/epidemiologia , Feminino , Humanos , Irlanda/epidemiologia , Masculino , Adulto Jovem
12.
Cleft Palate Craniofac J ; 59(6): 724-731, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-34109829

RESUMO

BACKGROUND: There may be many reasons for delays to primary cleft surgery. Our aim was to investigate the age of children undergoing primary cleft lip or primary cleft palate repair in 5 cleft centers within the United Kingdom. Identify the reasons for delayed primary cleft lip repair (beyond 6 months) and delayed primary palate repair (beyond 13 months). Identify children who had a cleft lip and/or palate (CL±P) that was intentionally unrepaired and the reasons for this. METHODS: A retrospective, multicenter review of patients born with a CL±P between December 1, 2012, and December 31, 2016. Three regional cleft centers, comprising of 5 cleft administrative units in the United Kingdom participated. RESULTS: In all, 1826 patients with CL±P were identified. Of them, 120 patients had delayed lip repair, outside the expected standard of 183 days. And, 178 patients in total had delayed palate repair, outside the expected standard of 396 days. Twenty (1%) patients had an unrepaired cleft palate. CONCLUSIONS: This large retrospective review highlights variations between centers regarding the timing of lip and palate surgery and details the reasons stated for delayed primary surgery. A small number of patients with an unrepaired cleft palate were identified. All had complex medical problems or comorbidities listed as a reason for the decision not to operate and 50% had a syndromic diagnosis. The number of patients receiving delayed surgery due to comorbidities, being underweight or prematurity, highlights the importance of the cleft specialist nurse and pediatrician within the cleft multidisciplinary team.


Assuntos
Fenda Labial , Fissura Palatina , Criança , Fenda Labial/cirurgia , Fissura Palatina/cirurgia , Humanos , Estudos Retrospectivos , Reino Unido
13.
J Sports Sci ; 38(21): 2415-2422, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32605426

RESUMO

Equipment scaling has yielded better performance in children in comparison to using adult equipment. To better inform applied practice in junior sport, an investigation of additional equipment modifications designed to further simplify the task is required. This study, therefore, aims to determine the effect of increasing surface area of cricket equipment (bats and balls) on batting performance and technique. Forty-three children (M age = 5.2, SD = 0.8 years) completed a cricket batting task in which they aimed to hit the ball through a target zone while using either regular-scaled, or modified bat and ball with an increased surface area. The number of bat-ball contacts was significantly higher when using the modified (M = 13.81, SE = 0.42) compared to the regular-scaled ball (M = 10.65, SE = 0.49). Batting performance measured as shots played through target areas was also significantly higher when using the modified (M = 31.78, SE = 1.97) than the regular-scaled ball (M = 28.85, SE = 2.27). More desirable technique was also observed when using the modified compared to the regular bat. Findings suggest that further modifications to regular-scaled equipment can enhance skill production.


Assuntos
Desempenho Atlético/fisiologia , Críquete/fisiologia , Desenho de Equipamento , Destreza Motora/fisiologia , Equipamentos Esportivos , Aceleração , Criança , Pré-Escolar , Feminino , Humanos , Masculino
15.
J Sports Sci ; 37(6): 613-620, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30317921

RESUMO

In table tennis the follow-through action after a shot is an important part of skill execution. In this experiment, we aimed to extend literature around the contextual interference effect by investigating whether the way the follow-through is organised in practice affects learning of the backhand shot in table tennis. Thirty unskilled participants were allocated to blocked-variable practice, random-variable practice or a control-constant group and aimed backhand shots towards a target following ball projection from a machine. Each group completed these shots in a pre-test, a training phase with follow-through manipulations, a post-test, and a retention test. The random-variable group improved their shot accuracy from pre-test to post-test and from pre-test to retention test (both P < 0.01, d = 1.03), whereas neither the blocked-variable nor the control-constant group displayed any change in shot accuracy. Practising the follow-through in a random-variable fashion enhanced learning of the preceding shot compared with blocked-variable practice or no follow-through instructions. The benefits of learning motor skills under conditions of high contextual interference also apply to how follow-through actions are organised. The findings are valuable to coaches and suggest that instructions related to the follow-through action should be considered as well as the primary skill itself.


Assuntos
Desempenho Atlético , Aprendizagem , Destreza Motora , Prática Psicológica , Tênis/fisiologia , Adulto , Feminino , Humanos , Masculino , Adulto Jovem
16.
Front Psychol ; 9: 2229, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30524338

RESUMO

Humans can rapidly discriminate complex scenarios as they unfold in real time, for example during law enforcement or, more prosaically, driving and sport. Such decision-making improves with experience, as new sources of information are exploited. For example, sports experts are able to predict the outcome of their opponent's next action (e.g., a tennis stroke) based on kinematic cues "read" from preparatory body movements. Here, we explore the use of psychophysical classification-image techniques to reveal how participants interpret complex scenarios. We used sport as a test case, filming tennis players serving and hitting ground strokes, each with two possible directions. These videos were presented to novices and club-level amateurs, running from 0.8 s before to 0.2 s after racquet-ball contact. During practice, participants anticipated shot direction under a time limit targeting 90% accuracy. Participants then viewed videos through Gaussian windows ("bubbles") placed at random in the temporal, spatial or spatiotemporal domains. Comparing bubbles from correct and incorrect trials revealed how information from different regions contributed toward a correct response. Temporally, only later frames of the videos supported accurate responding (from ~0.05 s before ball contact to 0.1 s afterwards). Spatially, information was accrued from the ball's trajectory and from the opponent's head. Spatiotemporal bubbles again highlighted ball trajectory information, but seemed susceptible to an attentional cuing artifact, which may caution against their wider use. Overall, bubbles proved effective in revealing regions of information accrual, and could thus be applied to help understand choice behavior in a range of ecologically valid situations.

17.
Q J Exp Psychol (Hove) ; 71(10): 2070-2087, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30226436

RESUMO

In dynamic, temporally constrained tasks, individuals often need to anticipate what will happen next prior to information becoming available within the environment. In such situations, the availability of contextual information can facilitate anticipation, often in conjunction with postural information. While many researchers have identified the specific sources of postural information facilitating anticipation, few have investigated the specific sources of contextual information employed. In two experiments, we presented skilled and less-skilled tennis players with animations of rallies from real matches that omitted access to postural information from the opponent, constraining participants to anticipate based on contextual information alone. In Experiment 1, participants anticipated the outcome of an opponent's shot under three conditions in which the sequence length (i.e., number of shots in a rally) preceding the same occluded shot was varied. Participants anticipated shot direction more accurately when the preceding shot sequence was presented than not. In Experiment 2, we presented animations that depicted the ball, the players, or both, in either dynamic or still form. Those conditions in which only the ball was depicted yielded the lowest response accuracy scores. It appears that information from the player and ball motion is required to provide the context under which skilled performers can consciously pick up and utilise information to anticipate more accurately than their less-skilled counterparts.


Assuntos
Antecipação Psicológica , Atenção/fisiologia , Cognição/fisiologia , Percepção de Movimento/fisiologia , Desempenho Psicomotor/fisiologia , Adulto , Percepção de Profundidade , Feminino , Humanos , Masculino , Orientação , Probabilidade , Tempo de Reação , Tênis , Interface Usuário-Computador , Adulto Jovem
18.
J Control Release ; 250: 86-95, 2017 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-28132935

RESUMO

Drug release from mesoporous silica systems has been widely investigated in vitro using USP Type II (paddle) dissolution apparatus. However, it is not clear if the observed enhanced in vitro dissolution can forecast drug bioavailability in vivo. In this study, the ability of different in vitro dissolution models to predict in vivo oral bioavailability in a pig model was examined. The fenofibrate-loaded mesoporous silica formulation was compared directly to a commercial reference product, Lipantil Supra®. Three in vitro dissolution methods were considered; USP Type II (paddle) apparatus, USP Type IV (flow-through cell) apparatus and a USP IV Transfer model (incorporating a SGF to FaSSIF-V2 media transfer). In silico modelling, using a physiologically based pharmacokinetic modelling and simulation software package (Gastroplus™), to generate in vitro/in vivo relationships, was also investigated. The study demonstrates that the in vitro dissolution performance of a mesoporous silica formulation varies depending on the dissolution apparatus utilised and experimental design. The findings show that the USP IV transfer model was the best predictor of in vivo bioavailability. The USP Type II (paddle) apparatus was not effective at forecasting in vivo behaviour. This observation is likely due to hydrodynamic differences between the two apparatus and the ability of the transfer model to better simulate gastrointestinal transit. The transfer model is advantageous in forecasting in vivo behaviour for formulations which promote drug supersaturation and as a result are prone to precipitation to a more energetically favourable, less soluble form. The USP IV transfer model could prove useful in future mesoporous silica formulation development. In silico modelling has the potential to assist in this process. However, further investigation is required to overcome the limitations of the model for solubility enhancing formulations.


Assuntos
Portadores de Fármacos/química , Dióxido de Silício/química , Animais , Disponibilidade Biológica , Química Farmacêutica , Simulação por Computador , Liberação Controlada de Fármacos , Feminino , Fenofibrato/química , Fenofibrato/farmacocinética , Humanos , Hidrodinâmica , Modelos Biológicos , Porosidade , Solubilidade , Suínos
19.
J Exp Psychol Appl ; 22(4): 455-470, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27936856

RESUMO

Skilled performers extract and process postural information from an opponent during anticipation more effectively than their less-skilled counterparts. In contrast, the role and importance of contextual information in anticipation has received only minimal attention. We evaluate the importance of contextual information in anticipation and examine the underlying perceptual-cognitive processes. We present skilled and less-skilled tennis players with normal video or animated footage of the same rallies. In the animated condition, sequences were created using player movement and ball trajectory data, and postural information from the players was removed, constraining participants to anticipate based on contextual information alone. Participants judged ball bounce location of the opponent's final occluded shot. The 2 groups were more accurate than chance in both display conditions with skilled being more accurate than less-skilled (Exp. 1) participants. When anticipating based on contextual information alone, skilled participants employed different gaze behaviors to less-skilled counterparts and provided verbal reports of thoughts which were indicative of more thorough evaluation of contextual information (Exp. 2). Findings highlight the importance of both postural and contextual information in anticipation and indicate that perceptual-cognitive expertise is underpinned by processes that facilitate more effective processing of contextual information, in the absence of postural information. (PsycINFO Database Record


Assuntos
Aptidão , Percepção de Movimento/fisiologia , Desempenho Psicomotor/fisiologia , Tempo de Reação/fisiologia , Percepção Visual/fisiologia , Adolescente , Adulto , Atenção/fisiologia , Cognição/fisiologia , Sinais (Psicologia) , Feminino , Humanos , Masculino , Tênis , Adulto Jovem
20.
Eur Radiol ; 26(1): 87-94, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26003790

RESUMO

OBJECTIVES: Endovascular embolization is a valid option for the management of visceral artery aneurysms. Imaging is crucial for providing anatomical assessments, but preoperative non-invasive investigations may not be exhaustive. The aim of this work is to present preliminary experience with the use of three-dimensional rotational angiography (3DRA) in this particular theatre. METHODS: Seven patients were treated for eight visceral aneurysms (six splenic and two renal) by endovascular embolization. 3DRA was performed before the treatment using a standard protocol. Different parameters (location of the lesion, the afferent and efferent vessels, aneurysm neck, vascular diameters, working incidence) were analyzed. RESULTS: 3DRA was successfully accomplished in all procedures. Mean aneurysm diameter was 23 mm and mean C-arm working incidence was 29° (R-L) and 9° (C-C). The sandwich technique was used in four lesions and the packing in the remaining four. Technical success was 100 %. The mean radiation dose per procedure was 291 600 mGy.cm(2). The mean procedural time was 2.25 hours. There were no immediate or short-term complications. CONCLUSIONS: 3DRA could be an interesting intraoperative tool to provide anatomical and technical assessments of the visceral arteries necessary for endovascular treatment, especially when information from preoperative imaging is not exhaustive. KEY POINTS: Endovascular embolization is a valid alternative solution for visceral artery aneurysm treatment. Imaging is crucial for anatomical assessments and treatment guidance. 3DRA can contribute to endovascular treatment in lieu of preoperative imaging.


Assuntos
Aneurisma/diagnóstico por imagem , Angiografia/métodos , Embolização Terapêutica/métodos , Procedimentos Endovasculares/métodos , Imageamento Tridimensional , Artéria Renal , Artéria Esplênica , Adulto , Idoso , Aneurisma/terapia , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Estudos Retrospectivos
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