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1.
Colorectal Dis ; 22(9): 1119-1129, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32040880

RESUMO

AIM: Early detection and removal of colorectal cancer (CRC) and advanced adenomas (AAs) decreases the incidence of and mortality from the disease. We aimed to evaluate the potential of faecal volatile organic compounds (VOCs) for detection and follow-up of colorectal adenoma using advanced electronic nose technology. METHOD: This was a prospective multi-centre case-control cohort including two district hospitals and one tertiary referral hospital. Patients undergoing colonoscopy were instructed to collect a faecal sample prior to bowel cleansing and were included in the study when CRC, AAs, large adenomas (LAs; 0.5-1.0 cm), small adenomas (SAs; 0.1-0.5 cm) or no endoscopic abnormalities (controls) were observed. Patients undergoing polypectomy and controls were asked for a second sample after 3 months. Faecal VOCs were measured with gas chromatography-ion mobility spectrometry. Random forest, support vector machine, Gaussian process and neural net classification were used to evaluate accuracy. RESULTS: In total, 14 patients with CRC, 64 with AAs, 69 with LAs, 127 with SAs and 227 controls were included. A second sample was collected from 32 polypectomy patients and 32 controls. Faecal VOCs discriminated CRC and adenomas from control [AUC (95% CI): CRC vs control 0.96 (0.89-1); AA vs control 0.96 (0.93-1); LA vs control 0.96 (0.92-0.99); SA vs control 0.96 (0.94-0.99)]. There were no significant differences between CRC and adenoma groups. Patients with adenomas and controls were discriminated prior to polypectomy, whereas 3 months after polypectomy VOC profiles were similar [T0 adenoma vs control 0.98 (0.95-1); T1 adenoma vs control 0.55 (0.40-0.69)]. CONCLUSIONS: Faecal VOC profiles may be useful for early detection of CRC and adenomas and the timing of polyp surveillance as polypectomy led to a normalization of the VOC profile.


Assuntos
Neoplasias Colorretais , Compostos Orgânicos Voláteis , Colonoscopia , Neoplasias Colorretais/diagnóstico , Detecção Precoce de Câncer , Seguimentos , Humanos , Estudos Prospectivos
2.
Hautarzt ; 71(9): 691-698, 2020 Sep.
Artigo em Alemão | MEDLINE | ID: mdl-32720165

RESUMO

ADVANTAGES OF ARTIFICIAL INTELLIGENCE (AI): With responsible, safe and successful use of artificial intelligence (AI), possible advantages in the field of dermato-oncology include the following: (1) medical work can focus on skin cancer patients, (2) patients can be more quickly and effectively treated despite the increasing incidence of skin cancer and the decreasing number of actively working dermatologists and (3) users can learn from the AI results. POTENTIAL DISADVANTAGES AND RISKS OF AI USE: (1) Lack of mutual trust can develop due to the decreased patient-physician contact, (2) additional time effort will be necessary to promptly evaluate the AI-classified benign lesions, (3) lack of adequate medical experience to recognize misclassified AI decisions and (4) recontacting a patient in due time in the case of incorrect AI classifications. Still problematic in the use of AI are the medicolegal situation and remuneration. Apps using AI currently cannot provide sufficient assistance based on clinical images of skin cancer. REQUIREMENTS AND POSSIBLE USE OF SMARTPHONE PROGRAM APPLICATIONS: Smartphone program applications (apps) can be implemented responsibly when the image quality is good, the patient's history can be entered easily, transmission of the image and results are assured and medicolegal aspects as well as remuneration are clarified. Apps can be used for disease-specific information material and can optimize patient care by using teledermatology.


Assuntos
Inteligência Artificial , Dermatologia/métodos , Melanoma/diagnóstico por imagem , Aplicativos Móveis , Neoplasias Cutâneas/diagnóstico por imagem , Smartphone , Telemedicina/instrumentação , Humanos , Interpretação de Imagem Assistida por Computador , Oncologia , Melanoma/diagnóstico , Neoplasias Cutâneas/diagnóstico
3.
Neth Heart J ; 28(11): 584-594, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32691341

RESUMO

INTRODUCTION: In patients with ST-elevation myocardial infarction (STEMI), percutaneous coronary intervention (PCI)-mediated reperfusion is preferred over pharmacoinvasive reperfusion with fibrinolysis if transfer to a PCI centre can be ensured in ≤120 min. We evaluated the ambulance driving time to primary PCI centres in the Netherlands and assessed to what extent ambulance driving times were impacted by the expansion of off-site PCI centres. METHODS AND RESULTS: We calculated the driving routes from every Dutch postal code to the nearest PCI centre with (on-site) or without (off-site) surgical back-up. We used data from ambulance records to estimate the ambulance driving time on each route. There were 16 on-site and 14 off-site PCI centres. The median (interquartile range) time to on-site PCI centres was 18.8 min (12.2-26.3) compared with 14.9 min (8.9-20.9) to any PCI centre (p < 0.001). In postal code areas that were impacted by the initiation of off-site PCI, the median driving time decreased from 25.4 (18.2-33.1) to 14.7 min (8.9-20.9) (p < 0.001). Ambulance driving times of >120 min were only seen in non-mainland areas. CONCLUSION: Based on a computational model, timely ambulance transfer to a PCI centre within 120 min is available to almost all STEMI patients in the Netherlands. Expansion of off-site PCI has significantly reduced the driving time to PCI centres.

4.
Chem Soc Rev ; 47(3): 852-908, 2018 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-29318245

RESUMO

In pursuit of more sustainable and competitive biorefineries, the effective valorisation of lignin is key. An alluring opportunity is the exploitation of lignin as a resource for chemicals. Three technological biorefinery aspects will determine the realisation of a successful lignin-to-chemicals valorisation chain, namely (i) lignocellulose fractionation, (ii) lignin depolymerisation, and (iii) upgrading towards targeted chemicals. This review provides a summary and perspective of the extensive research that has been devoted to each of these three interconnected biorefinery aspects, ranging from industrially well-established techniques to the latest cutting edge innovations. To navigate the reader through the overwhelming collection of literature on each topic, distinct strategies/topics were delineated and summarised in comprehensive overview figures. Upon closer inspection, conceptual principles arise that rationalise the success of certain methodologies, and more importantly, can guide future research to further expand the portfolio of promising technologies. When targeting chemicals, a key objective during the fractionation and depolymerisation stage is to minimise lignin condensation (i.e. formation of resistive carbon-carbon linkages). During fractionation, this can be achieved by either (i) preserving the (native) lignin structure or (ii) by tolerating depolymerisation of the lignin polymer but preventing condensation through chemical quenching or physical removal of reactive intermediates. The latter strategy is also commonly applied in the lignin depolymerisation stage, while an alternative approach is to augment the relative rate of depolymerisation vs. condensation by enhancing the reactivity of the lignin structure towards depolymerisation. Finally, because depolymerised lignins often consist of a complex mixture of various compounds, upgrading of the raw product mixture through convergent transformations embodies a promising approach to decrease the complexity. This particular upgrading approach is termed funneling, and includes both chemocatalytic and biological strategies.

5.
Neuroimage ; 180(Pt A): 253-266, 2018 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-28723578

RESUMO

Representations learned by deep convolutional neural networks (CNNs) for object recognition are a widely investigated model of the processing hierarchy in the human visual system. Using functional magnetic resonance imaging, CNN representations of visual stimuli have previously been shown to correspond to processing stages in the ventral and dorsal streams of the visual system. Whether this correspondence between models and brain signals also holds for activity acquired at high temporal resolution has been explored less exhaustively. Here, we addressed this question by combining CNN-based encoding models with magnetoencephalography (MEG). Human participants passively viewed 1,000 images of objects while MEG signals were acquired. We modelled their high temporal resolution source-reconstructed cortical activity with CNNs, and observed a feed-forward sweep across the visual hierarchy between 75 and 200 ms after stimulus onset. This spatiotemporal cascade was captured by the network layer representations, where the increasingly abstract stimulus representation in the hierarchical network model was reflected in different parts of the visual cortex, following the visual ventral stream. We further validated the accuracy of our encoding model by decoding stimulus identity in a left-out validation set of viewed objects, achieving state-of-the-art decoding accuracy.


Assuntos
Redes Neurais de Computação , Reconhecimento Visual de Modelos/fisiologia , Córtex Visual/fisiologia , Adulto , Feminino , Humanos , Magnetoencefalografia/métodos , Masculino , Processamento de Sinais Assistido por Computador , Adulto Jovem
6.
Epidemiol Infect ; 143(15): 3227-34, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25865382

RESUMO

On 23 May 2011, CDC identified a multistate cluster of Salmonella Heidelberg infections and two multidrug-resistant (MDR) isolates from ground turkey retail samples with indistinguishable pulsed-field gel electrophoresis patterns. We defined cases as isolation of outbreak strains in persons with illness onset between 27 February 2011 and 10 November 2011. Investigators collected hypothesis-generating questionnaires and shopper-card information. Food samples from homes and retail outlets were collected and cultured. We identified 136 cases of S. Heidelberg infection in 34 states. Shopper-card information, leftover ground turkey from a patient's home containing the outbreak strain and identical antimicrobial resistance profiles of clinical and retail samples pointed to plant A as the source. On 3 August, plant A recalled 36 million pounds of ground turkey. This outbreak increased consumer interest in MDR Salmonella infections acquired through United States-produced poultry and played a vital role in strengthening food safety policies related to Salmonella and raw ground poultry.


Assuntos
Surtos de Doenças , Farmacorresistência Bacteriana Múltipla , Microbiologia de Alimentos , Indústria de Embalagem de Carne , Intoxicação Alimentar por Salmonella/epidemiologia , Salmonella/fisiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Criança , Pré-Escolar , Eletroforese em Gel de Campo Pulsado , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Salmonella/efeitos dos fármacos , Salmonella/isolamento & purificação , Intoxicação Alimentar por Salmonella/microbiologia , Perus , Estados Unidos/epidemiologia , Adulto Jovem
7.
Epidemiol Infect ; 143(16): 3451-8, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25865140

RESUMO

The 2013 multistate outbreaks contributed to the largest annual number of reported US cases of cyclosporiasis since 1997. In this paper we focus on investigations in Texas. We defined an outbreak-associated case as laboratory-confirmed cyclosporiasis in a person with illness onset between 1 June and 31 August 2013, with no history of international travel in the previous 14 days. Epidemiological, environmental, and traceback investigations were conducted. Of the 631 cases reported in the multistate outbreaks, Texas reported the greatest number of cases, 270 (43%). More than 70 clusters were identified in Texas, four of which were further investigated. One restaurant-associated cluster of 25 case-patients was selected for a case-control study. Consumption of cilantro was most strongly associated with illness on meal date-matched analysis (matched odds ratio 19·8, 95% confidence interval 4·0-∞). All case-patients in the other three clusters investigated also ate cilantro. Traceback investigations converged on three suppliers in Puebla, Mexico. Cilantro was the vehicle of infection in the four clusters investigated; the temporal association of these clusters with the large overall increase in cyclosporiasis cases in Texas suggests cilantro was the vehicle of infection for many other cases. However, the paucity of epidemiological and traceback information does not allow for a conclusive determination; moreover, molecular epidemiological tools for cyclosporiasis that could provide more definitive linkage between case clusters are needed.


Assuntos
Coriandrum/parasitologia , Cyclospora/isolamento & purificação , Ciclosporíase/epidemiologia , Surtos de Doenças , Doenças Transmitidas por Alimentos/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Criança , Pré-Escolar , Análise por Conglomerados , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Texas/epidemiologia , Adulto Jovem
8.
Recent Results Cancer Res ; 203: 15-21, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25102995

RESUMO

With the widespread introduction of population screening for colorectal cancer in Europe, the number of early rectal cancers is expected to increase. In the past, approximately 25 % of rectal cancers presented with early disease, defined as stage I disease. First, results from population screening in the UK demonstrate an increase to approximately 50 % stage I for screen-detected carcinomas. In the absence of lymph node metastases, local excision of the tumor might be an attractive option, with considerably less morbidity due to surgery and a lower mortality. This option demonstrates the need for a reliable method of lymph node metastasis prediction in early rectal cancer. The overall risk of lymph node metastasis in pT1 tumors is still considerable, 11.4 %. In order to avoid both under-and overtreatment, we need adequate risk factors.


Assuntos
Neoplasias Retais/patologia , Humanos , Metástase Linfática , Estadiamento de Neoplasias
9.
Recent Results Cancer Res ; 203: 41-6, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25102998

RESUMO

High local recurrence rates were a major problem in rectal cancer treatment, with between 30 and 50 % of patients affected, resulting in a very poor quality of life and short survival of patients with rectal cancer. In recent years, prognosis of rectal cancer has markedly improved, due to innovations in surgical treatment in combination with neoadjuvant therapy. Quality evaluation of surgical procedures has become the standard; constant high quality of surgery is one of the major successes in rectal cancer over the last decade. Continuous monitoring of surgical procedures is a new role for the pathologist. Completeness of excision, resection margins, but also numbers of lymph nodes have been firmly established as quality indicators.


Assuntos
Neoplasias Retais/cirurgia , Humanos , Linfonodos/patologia , Indicadores de Qualidade em Assistência à Saúde , Neoplasias Retais/patologia
10.
Cereb Cortex ; 23(4): 824-32, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22455840

RESUMO

In order to execute a correct eye movement to a target in a search display, a saccade program toward the target element must be activated, while saccade programs toward distracting elements must be inhibited. The aim of the present study was to elucidate the role of the frontal eye fields (FEFs) in oculomotor competition. Functional magnetic resonance imaging-guided single-pulse transcranial magnetic stimulation (TMS) was administered over either the left FEF, the right FEF, or the vertex (control site) at 3 time intervals after target presentation, while subjects performed an oculomotor capture task. When TMS was applied over the FEF contralateral to the visual field where a target was presented, there was less interference of an ipsilateral distractor compared with FEF stimulation ipsilateral to the target's visual field or TMS over vertex. Furthermore, TMS over the FEFs decreased latencies of saccades to the contralateral visual field, irrespective of whether the saccade was directed to the target or to the distractor. These findings show that single-pulse TMS over the FEFs enhances the selection of a target in the contralateral visual field and decreases saccade latencies to the contralateral visual field.


Assuntos
Mapeamento Encefálico , Olho , Córtex Pré-Frontal/fisiologia , Movimentos Sacádicos/fisiologia , Estimulação Magnética Transcraniana , Vias Visuais/fisiologia , Adulto , Atenção/fisiologia , Percepção de Cores , Dominância Ocular , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Oxigênio/sangue , Córtex Pré-Frontal/irrigação sanguínea , Tempo de Reação/fisiologia , Campos Visuais/fisiologia , Vias Visuais/irrigação sanguínea
11.
Sci Total Environ ; 950: 175062, 2024 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-39098422

RESUMO

Pollination is crucial for biodiversity and food security. Heterogeneous agricultural landscapes have a positive effect on pollinator abundance and enhance crop production and quality. In this study, we explored the effects of three landscape features (past crop diversity measured as the Equivalent Richness of crop functional Groups in the previous year [ERGp], semi-natural habitat percentage [SNH], and mean field size [MFS]) and pollinator densities (wild bees [WB] and honey bees [HB]) on pollination and seed quantity and quality in rapeseed crops. Surveying the pollinator density in 20 rapeseed fields revealed a positive relationship with ERGp in the landscape. A pollinator exclusion experiment compared bagged and open-pollinated self-compatible rapeseed plants and revealed insect pollination effectiveness (fruits per flower and number of seeds per pod) and seed quality (oil content). Seed parameters were evaluated in relation to pollinator density (WB-HB) and landscape characteristics. The ERGp emerged as a crucial landscape feature that positively impacted WB density. When insect pollinators were excluded, plants exhibited reduced pollination effectiveness and seed quality. Analysis of open-pollinated plants highlighted ERGp as the most influential variable, positively affecting both sets of parameters. The MFS and SNH showed different but important relationships. Total tocopherol and α-tocopherol were positively correlated with pollinator density in HB, whereas WB showed a positive correlation with γ-tocopherol levels. Increased ERGp positively affected pollinator density and pollination effectiveness, thereby improving oilseed rape production quantity and quality. This study provides new insights into agroecosystem management and pollinator-friendly practices.


Assuntos
Agricultura , Produtos Agrícolas , Polinização , Animais , Agricultura/métodos , Abelhas/fisiologia , Biodiversidade , Brassica rapa/fisiologia , Brassica napus/fisiologia , Sementes/fisiologia
12.
NPJ Breast Cancer ; 10(1): 10, 2024 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-38245552

RESUMO

Accurate prediction of response to neoadjuvant chemotherapy (NAC) can help tailor treatment to individual patients' needs. Little is known about the combination of liquid biopsies and computer extracted features from multiparametric magnetic resonance imaging (MRI) for the prediction of NAC response in breast cancer. Here, we report on a prospective study with the aim to explore the predictive potential of this combination in adjunct to standard clinical and pathological information before, during and after NAC. The study was performed in four Dutch hospitals. Patients without metastases treated with NAC underwent 3 T multiparametric MRI scans before, during and after NAC. Liquid biopsies were obtained before every chemotherapy cycle and before surgery. Prediction models were developed using penalized linear regression to forecast residual cancer burden after NAC and evaluated for pathologic complete response (pCR) using leave-one-out-cross-validation (LOOCV). Sixty-one patients were included. Twenty-three patients (38%) achieved pCR. Most prediction models yielded the highest estimated LOOCV area under the curve (AUC) at the post-treatment timepoint. A clinical-only model including tumor grade, nodal status and receptor subtype yielded an estimated LOOCV AUC for pCR of 0.76, which increased to 0.82 by incorporating post-treatment radiological MRI assessment (i.e., the "clinical-radiological" model). The estimated LOOCV AUC was 0.84 after incorporation of computer-extracted MRI features, and 0.85 when liquid biopsy information was added instead of the radiological MRI assessment. Adding liquid biopsy information to the clinical-radiological resulted in an estimated LOOCV AUC of 0.86. In conclusion, inclusion of liquid biopsy-derived markers in clinical-radiological prediction models may have potential to improve prediction of pCR after NAC in breast cancer.

13.
Clin Transl Radiat Oncol ; 44: 100696, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37965060

RESUMO

Background: Elective neck irradiation (ENI) is performed in head and neck cancer patients treated with definitive (chemo)radiotherapy. The aim is to eradicate nodal metastases that are not detectable by pretreatment imaging techniques. It is conceivable that personalized neck irradiation can be performed guided by the results of sentinel lymph node biopsy (SLNB). It is expected that ENI can be omitted to one or both sides of the neck in 9 out of 10 patients, resulting in less radiation side effects with better quality of life. Methods/design: This is a multicenter randomized controlled trial aiming to compare safety and efficacy of treatment with SLNB guided neck irradiation versus standard bilateral ENI in 242 patients with cN0 squamous cell carcinoma of the oropharynx, larynx or hypopharynx for whom bilateral ENI is indicated. Patients randomized to the experimental-arm will undergo SLNB. Based on the histopathologic status of the SLNs, patients will receive no ENI (if all SLNs are negative), unilateral neck irradiation only (if a SLN is positive at one side of the neck) or bilateral neck irradiation (if SLNs are positive at both sides of the neck). Patients randomized to the control arm will not undergo SLNB but will receive standard bilateral ENI. The primary safety endpoint is the number of patients with recurrence in regional lymph nodes within 2 years after treatment. The primary efficacy endpoint is patient reported xerostomia-related quality of life at 6 months after treatment. Discussion: If this trial demonstrates that the experimental treatment is non-inferior to the standard treatment in terms of regional recurrence and is superior in terms of xerostomia-related quality of life, this will become the new standard of care.

14.
Appl Environ Microbiol ; 79(17): 5197-207, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23793638

RESUMO

The ability of Saccharomyces cerevisiae to efficiently produce high levels of ethanol through glycolysis has been the focus of much scientific and industrial activity. Despite the accumulated knowledge regarding glycolysis, the modification of flux through this pathway to modify ethanol yields has proved difficult. Here, we report on the systematic screening of 66 strains with deletion mutations of genes encoding enzymes involved in central carbohydrate metabolism for altered ethanol yields. Five of these strains showing the most prominent changes in carbon flux were selected for further investigation. The genes were representative of trehalose biosynthesis (TPS1, encoding trehalose-6-phosphate synthase), central glycolysis (TDH3, encoding glyceraldehyde-3-phosphate dehydrogenase), the oxidative pentose phosphate pathway (ZWF1, encoding glucose-6-phosphate dehydrogenase), and the tricarboxylic acid (TCA) cycle (ACO1 and ACO2, encoding aconitase isoforms 1 and 2). Two strains exhibited lower ethanol yields than the wild type (tps1Δ and tdh3Δ), while the remaining three showed higher ethanol yields. To validate these findings in an industrial yeast strain, the TPS1 gene was selected as a good candidate for genetic modification to alter flux to ethanol during alcoholic fermentation in wine. Using low-strength promoters active at different stages of fermentation, the expression of the TPS1 gene was slightly upregulated, resulting in a decrease in ethanol production and an increase in trehalose biosynthesis during fermentation. Thus, the mutant screening approach was successful in terms of identifying target genes for genetic modification in commercial yeast strains with the aim of producing lower-ethanol wines.


Assuntos
Etanol/metabolismo , Engenharia Metabólica , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Trealose/metabolismo , Vinho/microbiologia , Deleção de Genes , Expressão Gênica , Redes e Vias Metabólicas/genética , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo
15.
Nanotechnology ; 24(6): 065202, 2013 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-23339892

RESUMO

The anti-reflective effect of dielectric coatings used in silicon solar cells has traditionally been the subject of intensive studies and practical applications. In recent years the interest has permanently grown in plasmonic layers based on metal nanoparticles, which are shown to increase light trapping in the underlying silicon. In the present work we have combined these two concepts by means of in situ synthesis of Au nanoparticles in a dielectric matrix (TiO2), which is commonly used as an anti-reflective coating in silicon solar cells, and added the third element: a 10-20% porosity in the matrix. The porosity is formed by means of a controllable wet etching by low concentration HF. As a consequence, the experimentally measured reflectance of silicon coated by such a plasmonic layer decreases to practically zero in a broad wavelength region around the localized surface plasmon resonance. Furthermore, we demonstrate that extinction and reflectance spectra of silicon coated by the plasmonic films can be successfully accounted for by means of Fresnel formulae, in which a double refractive index of the metal-dielectric material is used. This double refractive index cannot be explained by effective medium theory (Maxwell-Garnett, for example) and appears when the contribution of Au nanoparticles located at the TiO2/Si interface is high enough to result in formation of interface surface plasmon modes.

16.
Sci Rep ; 13(1): 740, 2023 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-36639409

RESUMO

Vertical ground reaction force (GRFz) measurements are the best tool for assessing horses' weight-bearing lameness. However, collection of these data is often impractical for clinical use. This study evaluates GRFz predicted using data from body-mounted IMUs and long short-term memory recurrent neural networks (LSTM-RNN). Twenty-four clinically sound horses, equipped with IMUs on the upper-body (UB) and each limb, walked and trotted on a GRFz measuring treadmill (TiF). Both systems were time-synchronised. Data from randomly selected 16, 4, and 4 horses formed training, validation, and test datasets, respectively. LSTM-RNN with different input sets (All, Limbs, UB, Sacrum, or Withers) were trained to predict GRFz curves or peak-GRFz. Our models could predict GRFz shapes at both gaits with RMSE below 0.40 N.kg-1. The best peak-GRFz values were obtained when extracted from the predicted curves by the all dataset. For both GRFz curves and peak-GRFz values, predictions made with the All or UB datasets were systematically better than with the Limbs dataset, showing the importance of including upper-body kinematic information for kinetic parameters predictions. More data should be gathered to confirm the usability of LSTM-RNN for GRFz predictions, as they highly depend on factors like speed, gait, and the presence of weight-bearing lameness.


Assuntos
Marcha , Coxeadura Animal , Cavalos , Animais , Membro Posterior , Caminhada , Fenômenos Biomecânicos , Redes Neurais de Computação , Membro Anterior
17.
Planta ; 236(2): 343-54, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22367063

RESUMO

Much effort has been focussed on better understanding the key signals that modulate floral senescence. Although ethylene is one of the most important regulators of floral senescence in several species, Lilium flowers show low sensitivity to ethylene; thus their senescence may be regulated by other hormones. In this study we have examined how (1) endogenous levels of hormones in various floral tissues (outer and inner tepals, androecium and gynoecium) vary throughout flower development, (2) endogenous levels of hormones in such tissues change in cut versus intact flowers at anthesis, and (3) spray applications of abscisic acid and pyrabactin alter flower longevity. Results show that floral tissues behave differently in their hormonal changes during flower development. Cytokinin and auxin levels mostly increased in tepals prior to anthesis and decreased later during senescence. In contrast, levels of abscisic acid increased during senescence, but only in outer tepals and the gynoecium, and during the latest stages. In addition, cut flowers at anthesis differed from intact flowers in the levels of abscisic acid and auxins in outer tepals, salicylic acid in inner tepals, cytokinins, gibberellins and jasmonic acid in the androecium, and abscisic acid and salicylic acid in the gynoecium, thus showing a clear differential response between floral tissues. Furthermore, spray applications of abscisic acid and pyrabactin in combination accelerated the latest stages of tepal senescence, yet only when flower senescence was delayed with Promalin. It is concluded that (1) floral tissues differentially respond in their endogenous variations of hormones during flower development, (2) cut flowers have drastic changes in the hormonal balance not only of outer and inner tepals but also of androecium and gynoecium, and (3) abscisic acid may accelerate the progression of tepal senescence in Lilium.


Assuntos
Ácido Abscísico/farmacologia , Flores/fisiologia , Regulação da Expressão Gênica de Plantas/fisiologia , Lilium/fisiologia , Reguladores de Crescimento de Plantas/metabolismo , Ácido Abscísico/análise , Ácido Abscísico/metabolismo , Ciclopentanos/análise , Ciclopentanos/metabolismo , Citocininas/análise , Citocininas/metabolismo , Etilenos/análise , Etilenos/metabolismo , Flores/efeitos dos fármacos , Flores/crescimento & desenvolvimento , Giberelinas/análise , Giberelinas/metabolismo , Ácidos Indolacéticos/análise , Ácidos Indolacéticos/metabolismo , Lilium/efeitos dos fármacos , Lilium/crescimento & desenvolvimento , Oxilipinas/análise , Oxilipinas/metabolismo , Reguladores de Crescimento de Plantas/análise , Reprodução , Ácido Salicílico/análise , Ácido Salicílico/metabolismo , Fatores de Tempo
18.
S Afr J Sports Med ; 32(1): v32i1a7737, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-36818975

RESUMO

Background: In an acute field-side setting, it is often challenging to differentiate benign sports-related concussion (SRC) from potential, more sinister, intracranial pathology. Moreover, recovery in the ensuing days and weeks is often complex as the resolution of classical signs and symptoms does not always follow a standard pattern. Aim: To highlight the value of a structured and repeated thorough clinical assessment approach toward SRC, particularly as atypical and unexpected sequences in patient recovery patterns may require further specialist referral and intervention. Findings: A football goalkeeper sustained a concussion in which symptoms failed to resolve as expected. Deterioration in his clinical condition led to an eventual diagnosis of Chiari malformation (type I), which required surgical intervention. Implications: Non-typical recovery patterns of concussion may be indicative of increased severity when considered retrospectively. However, clinicians should not discount the possibility of underlying conditions.

19.
PLoS One ; 15(7): e0236138, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32645084

RESUMO

[This corrects the article DOI: 10.1371/journal.pone.0233266.].

20.
PLoS One ; 15(7): e0236181, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32645086

RESUMO

[This corrects the article DOI: 10.1371/journal.pone.0233649.].

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