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1.
Eur Radiol ; 34(2): 1157-1166, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37624414

RESUMO

OBJECTIVES: As structured reporting is increasingly used in the evaluation of prostate-specific membrane antigen positron emission tomography/computed tomography (PSMA-PET/CT) for prostate cancer, there is a need to assess the reliability of these frameworks. This study aimed to evaluate the intra- and interreader agreement among readers with varying levels of experience using PSMA-RADS 1.0 for interpreting PSMA-PET/CT scans, even when blinded to clinical data, and therefore to determine the feasibility of implementing this reporting system in clinical practice. METHODS: PSMA-PET/CT scans of 103 patients were independently evaluated by 4 readers with different levels of experience according to the reporting and data system (RADS) for PSMA-PET/CT imaging PSMA-RADS 1.0 at 2 time points within 6 weeks. For each scan, a maximum of five target lesions were freely chosen and stratified according to PSMA-RADS 1.0. Overall scan score and compartment-based scores were assessed. Intra- and interreader agreement was determined using the intraclass correlation coefficient (ICC). RESULTS: PSMA-RADS 1.0 demonstrated excellent interreader agreement for both overall scan scores (ICC ≥ 0.91) and compartment-based scores (ICC ≥ 0.93) across all four readers. The framework showed excellent intrareader agreement for overall scan scores (ICC ≥ 0.86) and compartment-based scores (ICC ≥ 0.95), even among readers with varying levels of experience. CONCLUSIONS: PSMA-RADS 1.0 is a reliable method for assessing PSMA-PET/CT with strong consistency and agreement among readers. It shows great potential for establishing a standard approach to diagnosing and planning treatment for prostate cancer patients, and can be used confidently even by readers with less experience. CLINICAL RELEVANCE STATEMENT: This study underlines that PSMA-RADS 1.0 is a valuable and highly reliable scoring system for PSMA-PET/CT scans of prostate cancer patients and can be used confidently by radiologists with different levels of experience in routine clinical practice. KEY POINTS: PSMA-RADS version 1.0 is a scoring system for PSMA-PET/CT scans. Its reproducibility needs to be analyzed in order to make it applicable to clinical practice. Excellent interreader and intrareader agreement for overall scan scores and compartment-based scores using PSMA-RADS 1.0 were seen in readers with varying levels of experience. PSMA-RADS 1.0 is a reliable tool for accurately diagnosing and planning treatment for prostate cancer patients, and can be used confidently in clinical routine.


Assuntos
Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Neoplasias da Próstata , Humanos , Masculino , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Reprodutibilidade dos Testes , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/patologia , Diagnóstico por Imagem , Radiologistas , Radioisótopos de Gálio
2.
Psychophysiology ; 61(8): e14586, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38594833

RESUMO

Previous work has indicated that individual differences in cognitive performance can be predicted by characteristics of resting state oscillations, such as individual peak alpha frequency (IAF). Although IAF has previously been correlated with cognitive functions, such as memory, attention, or mental speed, its link to cognitive conflict processing remains unexplored. The current work investigated the relationship between IAF and inhibitory cognitive control in two well-established conflict tasks, Stroop and Navon task, while also controlling for alpha power, theta power, and the 1/f offset of aperiodic broadband activity. In Bayesian analyses on a large sample of 127 healthy participants, we found substantial evidence against the assumption that IAF predicts individual abilities to spontaneously exert cognitive control. Similarly, our findings yielded substantial evidence against links between cognitive control and resting state power in the alpha and theta bands or between cognitive control and aperiodic 1/f offset. In sum, our results challenge frameworks suggesting that an individual's ability to spontaneously engage attentional control networks may be mirrored in resting state EEG characteristics.


Assuntos
Ritmo alfa , Função Executiva , Individualidade , Inibição Psicológica , Humanos , Masculino , Feminino , Ritmo alfa/fisiologia , Adulto , Adulto Jovem , Função Executiva/fisiologia , Eletroencefalografia , Teste de Stroop , Cognição/fisiologia , Atenção/fisiologia , Adolescente , Ritmo Teta/fisiologia , Desempenho Psicomotor/fisiologia , Teorema de Bayes
3.
Eur Radiol ; 33(5): 3416-3424, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36964768

RESUMO

OBJECTIVES: The recently proposed standardized reporting and data system for somatostatin receptor (SSTR)-targeted PET/CT SSTR-RADS 1.0 showed promising first results in the assessment of diagnosis and treatment planning with peptide receptor radionuclide therapy (PRRT) in neuroendocrine tumors (NET). This study aimed to determine the intra- and interreader agreement of SSTR-RADS 1.0. METHODS: SSTR-PET/CT scans of 100 patients were independently evaluated by 4 readers with different levels of expertise according to the SSTR-RADS 1.0 criteria at 2 time points within 6 weeks. For each scan, a maximum of five target lesions were freely chosen by each reader (not more than three lesions per organ) and stratified according to the SSTR-RADS 1.0 criteria. Overall scan score and binary decision on PRRT were assessed. Intra- and interreader agreement was determined using the intraclass correlation coefficient (ICC). RESULTS: Interreader agreement using SSTR-RADS 1.0 for identical target lesions (ICC ≥ 0.91) and overall scan score (ICC ≥ 0.93) was excellent. The decision to state "functional imaging fulfills requirements for PRRT and qualifies patient as potential candidate for PRRT" also demonstrated excellent agreement among all readers (ICC ≥ 0.86). Intrareader agreement was excellent even among different experience levels when comparing target lesion-based scores (ICC ≥ 0.98), overall scan score (ICC ≥ 0.93), and decision for PRRT (ICC ≥ 0.88). CONCLUSION: SSTR-RADS 1.0 represents a highly reproducible and accurate system for stratifying SSTR-targeted PET/CT scans with high intra- and interreader agreement. The system is a promising approach to standardize the diagnosis and treatment planning in NET patients. KEY POINTS: • SSTR-RADS 1.0 offers high reproducibility and accuracy. • SSTR-RADS 1.0 is a promising method to standardize diagnosis and treatment planning for patients with NET.


Assuntos
Tumores Neuroendócrinos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Humanos , Receptores de Somatostatina , Tumores Neuroendócrinos/diagnóstico por imagem , Tumores Neuroendócrinos/terapia , Tumores Neuroendócrinos/patologia , Reprodutibilidade dos Testes , Cintilografia
4.
J Cogn Neurosci ; 34(9): 1702-1717, 2022 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-35704553

RESUMO

Using a combination of behavioral and EEG measures in a tactile odd-one-out search task with collocated visual items, we investigated the mechanisms underlying facilitation of search by repeated (vs. nonrepeated) spatial distractor-target configurations ("contextual cueing") when either the tactile (same-modality) or the visual array (different-modality) context was predictive of the location of the tactile singleton target. Importantly, in both conditions, the stimulation was multisensory, consisting of tactile plus visual items, although the target was singled out in the tactile modality and so the visual items were task-irrelevant. We found that when the predictive context was tactile, facilitation of search RTs by repeated configurations was accompanied by, and correlated with, enhanced lateralized ERP markers of pre-attentive (N1, N2) and, respectively focal-attentional processing (contralateral delay activity) not only over central ("somatosensory"), but also posterior ("visual") electrode sites, although the ERP effects were less marked over visual cortex. A similar pattern-of facilitated RTs and enhanced lateralized (N2 and contralateral delay activity) ERP components-was found when the predictive context was visual, although the ERP effects were less marked over somatosensory cortex. These findings indicate that both somatosensory and visual cortical regions contribute to the more efficient processing of the tactile target in repeated stimulus arrays, although their involvement is differentially weighted depending on the sensory modality that contains the predictive information.


Assuntos
Percepção do Tato , Tato , Atenção/fisiologia , Sinais (Psicologia) , Humanos , Córtex Somatossensorial/fisiologia , Tato/fisiologia , Percepção do Tato/fisiologia
5.
PLoS Comput Biol ; 17(9): e1009332, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34478446

RESUMO

In visual search tasks, repeating features or the position of the target results in faster response times. Such inter-trial 'priming' effects occur not just for repetitions from the immediately preceding trial but also from trials further back. A paradigm known to produce particularly long-lasting inter-trial effects-of the target-defining feature, target position, and response (feature)-is the 'priming of pop-out' (PoP) paradigm, which typically uses sparse search displays and random swapping across trials of target- and distractor-defining features. However, the mechanisms underlying these inter-trial effects are still not well understood. To address this, we applied a modeling framework combining an evidence accumulation (EA) model with different computational updating rules of the model parameters (i.e., the drift rate and starting point of EA) for different aspects of stimulus history, to data from a (previously published) PoP study that had revealed significant inter-trial effects from several trials back for repetitions of the target color, the target position, and (response-critical) target feature. By performing a systematic model comparison, we aimed to determine which EA model parameter and which updating rule for that parameter best accounts for each inter-trial effect and the associated n-back temporal profile. We found that, in general, our modeling framework could accurately predict the n-back temporal profiles. Further, target color- and position-based inter-trial effects were best understood as arising from redistribution of a limited-capacity weight resource which determines the EA rate. In contrast, response-based inter-trial effects were best explained by a bias of the starting point towards the response associated with a previous target; this bias appeared largely tied to the position of the target. These findings elucidate how our cognitive system continually tracks, and updates an internal predictive model of, a number of separable stimulus and response parameters in order to optimize task performance.


Assuntos
Simulação por Computador , Humanos , Tempo de Reação/fisiologia , Reprodutibilidade dos Testes , Análise e Desempenho de Tarefas
6.
J Acoust Soc Am ; 150(2): 1231, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34470322

RESUMO

The application of a porous coating to a smooth cylinder placed in uniform flow can reduce its vortex shedding tone and overall sound pressure level. The responsible noise generation mechanisms are not fully understood nor has an optimal porous coating type been presented. Structured Porous Coated Cylinders (SPCCs) have been recently investigated as an alternative to randomized porous coated cylinders that use metal foam or polyurethane. SPCCs possess similar noise reduction characteristics to randomized porous coated cylinders, yet their porosity can be modified in circumferential and spanwise directions. An acoustic investigation was conducted in a small anechoic wind tunnel using SPCCs constructed in four spanwise segments, yielding varying spanwise and circumferential porosities. Acoustic signals were recorded using two microphone arc arrays symmetric about the flow axis. Each SPCC revealed a reduced vortex shedding tone, a primary harmonic, and a high frequency broadband contribution. For each SPCC, the vortex shedding tones were weaker than the equivalent bare cylinder shedding tone and presented decreased overall sound pressure level. Variations in circumferential and spanwise porosity were shown to have little effect on tonal noise reduction yet influence high frequency contributions.

7.
Medicina (Kaunas) ; 57(1)2021 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-33435420

RESUMO

Background and Objectives: Vesicoureteral reflux (VUR) describes a common pediatric anomaly in pediatric urology with a prevalence of 1-2%. In diagnostics, in addition to the gold standard of voiding cystourethrography (VCUG), contrast-enhanced urosonography (ceVUS) offers a radiation-free procedure, which, despite its advantages, is not yet widely used. In the present single-center study, subsequent therapeutic procedures and outcomes after ceVUS of 49 patients were investigated. The aim of the study is to investigate the efficacy of ceVUS with the intention of broader clinical implementation. Materials and Methods: Between 2016 and 2020, 49 patients were retrospectively included and received a ceVUS to evaluate VUR. With a distribution of 47:2 (95.9%), a clear female predominance was present. The age of the patients varied between 5 months and 60 years at the time of ceVUS. All examinations were all performed and subsequently interpreted by a single experienced radiologist (EFSUMB level 3). Results: Compared to intraoperative findings, ceVUS shows a sensitivity of 95.7% with a specificity of 100%. Allergic reactions to the contrast medium could not be observed. Conclusion: With its high sensitivity and intraoperative validation, ceVUS offers an excellent alternative to VCUG, the gold standard in the diagnosis of VUR. In addition, ceVUS is a radiation-free examination method with a low risk profile that offers an exceptional diagnostic tool in the diagnostic clarification of recurrent urinary tract infections with the suspected diagnosis of VUR and should also be included in the consideration of a diagnosis next to the established VCUG, especially in younger children.


Assuntos
Meios de Contraste , Técnicas de Diagnóstico Urológico , Ultrassonografia/métodos , Refluxo Vesicoureteral/diagnóstico por imagem , Adolescente , Adulto , Antibacterianos/uso terapêutico , Criança , Pré-Escolar , Cistografia , Feminino , Humanos , Lactente , Injeções , Laparoscopia , Masculino , Pessoa de Meia-Idade , Fosfolipídeos , Politetrafluoretileno , Exposição à Radiação , Recidiva , Sensibilidade e Especificidade , Índice de Gravidade de Doença , Hexafluoreto de Enxofre , Ureteroscopia , Uretra/diagnóstico por imagem , Bexiga Urinária/diagnóstico por imagem , Infecções Urinárias/etiologia , Infecções Urinárias/prevenção & controle , Urografia , Refluxo Vesicoureteral/classificação , Refluxo Vesicoureteral/complicações , Refluxo Vesicoureteral/terapia , Adulto Jovem
8.
Psychol Sci ; 31(12): 1531-1543, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33119432

RESUMO

Visual search is facilitated when the target is repeatedly encountered at a fixed position within an invariant (vs. randomly variable) distractor layout-that is, when the layout is learned and guides attention to the target, a phenomenon known as contextual cuing. Subsequently changing the target location within a learned layout abolishes contextual cuing, which is difficult to relearn. Here, we used lateralized event-related electroencephalogram (EEG) potentials to explore memory-based attentional guidance (N = 16). The results revealed reliable contextual cuing during initial learning and an associated EEG-amplitude increase for repeated layouts in attention-related components, starting with an early posterior negativity (N1pc, 80-180 ms). When the target was relocated to the opposite hemifield following learning, contextual cuing was effectively abolished, and the N1pc was reversed in polarity (indicative of persistent misguidance of attention to the original target location). Thus, once learned, repeated layouts trigger attentional-priority signals from memory that proactively interfere with contextual relearning after target relocation.


Assuntos
Sinais (Psicologia) , Aprendizagem , Humanos , Tempo de Reação , Percepção Visual
9.
J Vis ; 20(7): 4, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38755793

RESUMO

Spatial attention can be deployed with a narrower focus to process individual items or distributed relatively broadly to process larger parts of a scene. This study investigated how focused- versus distributed-attention modes contribute to the adaptation of context-based memories that guide visual search. In two experiments, participants were either required to fixate the screen center and use peripheral vision for search ("distributed attention"), or they could freely move their eyes, enabling serial scanning of the search array ("focused attention"). Both experiments consisted of an initial learning phase and a subsequent test phase. During learning, participants searched for targets presented either among repeated (invariant) or nonrepeated (randomly generated) spatial layouts of distractor items. Prior research showed that repeated encounters of invariant display arrangements lead to long-term context memory about these arrays, which can then come to guide search (contextual-cueing effect). The crucial manipulation in the test phase was a change of the target location within an otherwise constant distractor layout, which has previously been shown to abolish the cueing effect. The current results replicated these findings, although importantly only when attention was focused. By contrast, with distributed attention, the cueing effect recovered rapidly and attained a level comparable to the initial effect (before the target location change). This indicates that contextual cueing can adapt more easily when attention is distributed, likely because a broad attentional set facilitates the flexible updating of global (distractor-distractor), as compared to more local (distractor-target), context representations-allowing local changes to be incorporated more readily.

10.
Medicina (Kaunas) ; 56(12)2020 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-33302381

RESUMO

Background and objectives: Native ultrasound is the most common imaging modality in obstetrics. The use of contrast-enhanced ultrasound (CEUS) during pregnancy has not been officially approved by leading societies for obstetrics and ultrasound. The present study aims to monitor the safety and diagnostic performance of CEUS for assessing abdominal issues in five pregnant women. Materials and Methods: Five pregnant patients who underwent a total of 11 CEUS examinations between June 2020 and October 2020 were included (mean age: 34 years; mean time of pregnancy: 21 weeks). All CEUS scans were interpreted by one experienced consultant radiologist (EFSUMB Level 3). Results: Upon contrast application, no maternal nor fetal adverse effects were observed. Moreover, no fetal contrast enhancement was observed in any patient. CEUS helped to diagnose renal angiomyolipoma, pyelonephritis, necrotic uterine fibroid, gallbladder polyp, and superior mesenteric vein thrombosis. Conclusions: In our study, off-label use of CEUS showed an excellent safety profile allowing the avoidance of ionizing radiation exposure as well as contrast agents in case of CT or use of gadolinium-based contrast agents in case of MRI. CEUS is a promising diagnostic instrument for facilitating clinical decision-making and improving the management of pregnant women.


Assuntos
Angiomiolipoma , Neoplasias Renais , Adulto , Meios de Contraste , Feminino , Humanos , Imageamento por Ressonância Magnética , Gravidez , Ultrassonografia
11.
Medicina (Kaunas) ; 56(11)2020 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-33227984

RESUMO

BACKGROUND: The present study aims to evaluate the diagnostic performance of contrast-enhanced ultrasound (CEUS) for discriminating between benign and malignant solid renal masses. METHODS: 18 patients with histopathologically confirmed benign solid renal masses (11 oncocytomas, seven angiomyolipomas) as well as 96 patients with confirmed renal cell carcinoma (RCC) who underwent CEUS followed by radical or partial nephrectomy were included in this single-center study. CEUS examinations were performed by an experienced radiologist (EFSUMB Level 3) and included the application of a second-generation contrast agent. RESULTS: Renal angiomyolipomas, oncocytomas, and renal cell carcinomas showed varying sonomorphological characteristics in CEUS. Angiomyolipomas showed heterogeneous echogenicity (57% hypo-, 43% hyperechoic), while all lesions showed rapid contrast-enhancement with two lesions also showing venous wash-out (29%). Notably, 9/11 oncocytomas could be detected in conventional ultrasound (64% hypo-, 9% hyper-, 9% isoechoic) and 2/11 only demarcated upon intravenous application of contrast agent (18%). All oncocytomas showed hyperenhancement in CEUS, venous wash-out was registered in 7/11 lesions (64%). CONCLUSIONS: In line with the current state of knowledge, no specific sonomorphological characteristics allowing for accurate distinction between benign and malignant solid renal masses in CEUS could be detected in our study.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Carcinoma de Células Renais/diagnóstico por imagem , Carcinoma de Células Renais/cirurgia , Meios de Contraste , Diagnóstico Diferencial , Humanos , Neoplasias Renais/diagnóstico por imagem , Estudos Retrospectivos , Ultrassonografia
12.
Medicina (Kaunas) ; 56(12)2020 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-33322683

RESUMO

Background and objectives: The aim of the present retrospective single-center study is to evaluate the diagnostic performance of contrast-enhanced ultrasound (CEUS) for assessing Bosniak III complex renal cystic lesions with histopathological validation. Materials and Methods: 49 patients with CEUS-categorized Bosniak III renal cystic lesions were included in this retrospective study. All patients underwent native B-mode, Color Doppler, contrast-enhanced ultrasound (CEUS) between 2010-2020. Eight and five patients underwent computed tomography (CT) and magnetic resonance imaging (MRI), respectively. Twenty-nine underwent (partial) nephrectomy allowing for histopathological analysis. The applied contrast agent for CEUS was a second-generation blood pool agent. Ultrasonography examinations were performed and interpreted by a single experienced radiologist with more than 15 years of experience (EFSUMB Level 3). Results: CEUS examinations were successfully performed in all included patients without registering any adverse effects. The malignancy rate of CEUS-categorized Bosniak III renal lesions accounted for 66%. Initially, cystic complexity was visualized in native B-mode. In none of the renal lesions hypervascularization was detected in Color Doppler. CEUS allowed for detection of contrast enhancement patterns in all included Bosniak III renal lesions. Delayed wash-out could be detected in 6/29 renal lesions. In two cases of histopathologically confirmed clear-cell RCC, appropriate up-grading from Bosniak IIF to III was achieved by CEUS. Conclusions: CEUS depicts a promising imaging modality for the precise diagnostic workup and stratification of renal cystic lesions according to the Bosniak classification system, thereby helping guidance of adequate clinical management in the future.


Assuntos
Meios de Contraste , Neoplasias Renais , Humanos , Rim/diagnóstico por imagem , Rim/cirurgia , Estudos Retrospectivos , Tomografia Computadorizada por Raios X , Ultrassonografia
13.
J Cogn Neurosci ; 31(3): 442-452, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30457915

RESUMO

This study investigates the causal contribution of the left frontopolar cortex (FPC) to the processing of violated expectations from learned target-distractor spatial contingencies during visual search. The experiment consisted of two phases: learning and test. Participants searched for targets presented either among repeated or nonrepeated target-distractor configurations. Prior research showed that repeated encounters of identically arranged displays lead to memory about these arrays, which then can come to guide search (contextual cueing effect). The crucial manipulation was a change of the target location, in a nevertheless constant distractor layout, at the transition from learning to test. In addition to this change, we applied repetitive transcranial magnetic stimulation (rTMS) over the left lateral FPC, over a posterior control site, or no rTMS at all (baseline; between-group manipulation) to see how FPC rTMS influences the ability of observers to adapt context-based memories acquired in the training phase. The learning phase showed expedited search in repeated relative to nonrepeated displays, with this context-based facilitation being comparable across all experimental groups. For the test phase, the recovery of cueing was critically dependent on the stimulation site: Although there was evidence of context adaptation toward the end of the experiment in the occipital and no-rTMS conditions, observers with FPC rTMS showed no evidence of relearning at all after target location changes. This finding shows that FPC plays an important role in the regulation of prediction errors in statistical context learning, thus contributing to an update of the spatial target-distractor contingencies after target position changes in learned spatial arrays.


Assuntos
Atenção/fisiologia , Lobo Frontal/fisiologia , Memória/fisiologia , Percepção Visual/fisiologia , Adulto , Feminino , Humanos , Aprendizagem/fisiologia , Masculino , Estimulação Luminosa , Tempo de Reação/fisiologia , Aprendizagem Espacial/fisiologia , Estimulação Magnética Transcraniana
14.
Breast Cancer Res Treat ; 173(2): 319-328, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30324275

RESUMO

PURPOSE: Neoadjuvant combination treatment with chemotherapy (CTX), trastuzumab (TZM), and pertuzumab (PTZ) has been shown to result in higher pathological complete response rates (pCR) in comparison with treatment with chemotherapy and trastuzumab (CTX/TZM). This analysis was aimed at real-world validation of these results from prospective randomized trials. METHODS: In a retrospective analysis conducted in the PRAEGNANT network, patients were eligible for inclusion if they had either received neoadjuvant therapy with CTX/TZM or chemotherapy, trastuzumab, and pertuzumab (CTX/TZM/PTZ) and subsequently underwent surgery for their primary breast cancer. The effect of the two neoadjuvant regimens on pCR in addition to commonly applicable predictors of pCR was analyzed in 300 patients from three study sites, using logistic regression analyses with treatment arm, age, clinical tumor stage, grading, and hormone receptor status as predictors. RESULTS: pCR with complete disappearance of all tumor cells was seen in 30.2% (n = 58) of patients treated with CTX/TZM and in 52.8% (n = 57) of those treated with CTX/TZM/PTZ. CTX/TZM/PTZ was positively associated with pCR (adjusted odds ratio 2.44; 95% CI 1.49-4.02). Mastectomy rates were not influenced by the therapy. CONCLUSIONS: The results of clinical trials were confirmed in this dataset of patients who were treated outside of clinical trials in everyday routine work. pCR rates can be improved by 20% with pertuzumab in routine clinical use.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/terapia , Trastuzumab/uso terapêutico , Adulto , Idoso , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Conjuntos de Dados como Assunto , Intervalo Livre de Doença , Feminino , Humanos , Mastectomia , Pessoa de Meia-Idade , Terapia Neoadjuvante/métodos , Estudos Prospectivos , Estudos Retrospectivos
15.
J Acoust Soc Am ; 143(6): 3460, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29960452

RESUMO

This paper is concerned with the influence of camber on the noise of a wall-mounted finite airfoil with natural boundary layer transition. Tonal noise measurements taken in an aeroacoustic wind tunnel are presented for airfoils with aspect ratio of 2, NACAxx12 profile and camber between 0 and 6% at 40% chord. The results show camber is an important parameter that determines the operating conditions for which acoustic tone generation occurs and the number and intensity of the tones produced. Airfoils with 0%-2% camber have an acoustic signature that is dominated by a high amplitude primary tone, whereas the spectra of airfoils with higher camber of 4%-6% feature a more pronounced side tone structure. Tonal noise production does not collapse with lift coefficient, demonstrating that the local flow conditions influence the noise source. Tonal noise production is explained in terms of changes to mean flow topology, namely the location of flow separation, which is linked to tonal noise generation. Scaling of airfoil tonal noise is found to vary with angle of attack and pressure gradient. Empirical scaling laws for the primary tone frequency dependence on velocity are also derived for the cambered airfoils.

16.
Behav Brain Sci ; 40: e155, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-29342617

RESUMO

Hulleman & Olivers' (H&O's) conceptual framework does not consider variation of fixation duration and its interaction with the size of the functional viewing field (FVF). Here we provide empirical evidence of a dynamic interaction between the two parameters, suggesting that fixations, as the central unit in H&O's framework, should be studied on both the spatial and temporal dimensions.


Assuntos
Fixação Ocular , Estimulação Luminosa , Movimentos Oculares
17.
J Exp Psychol Learn Mem Cogn ; 50(5): 699-711, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-37917510

RESUMO

Visual search is faster when a fixed target location is paired with a spatially invariant (vs. randomly changing) distractor configuration, thus indicating that repeated contexts are learned, thereby guiding attention to the target (contextual cueing [CC]). Evidence for memory-guided attention has also been revealed with electrophysiological (electroencephalographic [EEG]) recordings, starting with an enhanced early posterior negativity (N1pc), which signals a preattentive bias toward the target, and, subsequently, attentional and postselective components, such as the posterior contralateral negativity (PCN) and contralateral delay activity (CDA), respectively. Despite effective learning, relearning of previously acquired contexts is inflexible: The CC benefits disappear when the target is relocated to a new position within an otherwise invariant context and corresponding EEG correlates are diminished. The present study tested whether global statistical properties that induce predictions going beyond the immediate invariant layout can facilitate contextual relearning. Global statistical regularities were implemented by presenting repeated and nonrepeated displays in separate streaks (mini blocks) of trials in the relocation phase, with individual displays being presented in a fixed and thus predictable order. Our results revealed a significant CC effect (and an associated modulation of the N1pc, PCN, and CDA components) during initial learning. Critically, the global statistical regularities in the relocation phase also resulted in a reliable CC effect, thus revealing effective relearning with predictive streaks. Moreover, this relearning was reflected in an enhanced PCN amplitude for repeated relative to nonrepeated contexts. Temporally ordered contexts may thus adapt memory-based guidance of attention, particularly the allocation of covert attention in the visual display. (PsycInfo Database Record (c) 2024 APA, all rights reserved).


Assuntos
Sinais (Psicologia) , Aprendizagem , Humanos , Aprendizagem/fisiologia , Rememoração Mental , Adaptação Fisiológica , Tempo de Reação/fisiologia
18.
Data Brief ; 52: 109825, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38370020

RESUMO

The very soft and flow-permeable plumage is among the special adaptations of the owl that the silent flight is attributed to. Using a specially designed apparatus that provides a low-speed volume flow of air through a small sample of porous material, measurements of the air flow permeability were performed in accordance to ISO 9053 on a total of 39 prepared wing specimen from six different bird species, including three species of silently flying owls and three non-silently flying bird species. The resulting data set described in the present paper contains the static airflow resistance measured at different positions on the wing.

19.
Psychon Bull Rev ; 31(1): 148-155, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37434045

RESUMO

Visual search for a target is faster when the spatial layout of distractors is repeatedly encountered, illustrating that statistical learning of contextual invariances facilitates attentional guidance (contextual cueing; Chun & Jiang, 1998, Cognitive Psychology, 36, 28-71). While contextual learning is usually relatively efficient, relocating the target to an unexpected location (within an otherwise unchanged search layout) typically abolishes contextual cueing and the benefits deriving from invariant contexts recover only slowly with extensive training (Zellin et al., 2014, Psychonomic Bulletin & Review, 21(4), 1073-1079). However, a recent study by Peterson et al. (2022, Attention, Perception, & Psychophysics, 84(2), 474-489) in fact reported rather strong adaptation of spatial contextual memories following target position changes, thus contrasting with prior work. Peterson et al. argued that previous studies may have been underpowered to detect a reliable recovery of contextual cueing after the change. However, their experiments also used a specific display design that frequently presented the targets at the same locations, which might reduce the predictability of the contextual cues thereby facilitating its flexible relearning (irrespective of statistical power). The current study was a (high-powered) replication of Peterson et al., taking into account both statistical power and target overlap in context-memory adaptation. We found reliable contextual cueing for the initial target location irrespective of whether the targets shared their location across multiple displays, or not. However, contextual adaptation following a target relocation event occurred only when target locations were shared. This suggests that cue predictability modulates contextual adaptation, over and above a possible (yet negligible) influence of statistical power.


Assuntos
Atenção , Sinais (Psicologia) , Humanos , Rememoração Mental , Memória Espacial , Psicofísica , Tempo de Reação
20.
Cortex ; 175: 41-53, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38703715

RESUMO

Visual search is speeded when a target is repeatedly presented in an invariant scene context of nontargets (contextual cueing), demonstrating observers' capability for using statistical long-term memory (LTM) to make predictions about upcoming sensory events, thus improving attentional orienting. In the current study, we investigated whether expectations arising from individual, learned environmental structures can encompass multiple target locations. We recorded event-related potentials (ERPs) while participants performed a contextual cueing search task with repeated and non-repeated spatial item configurations. Notably, a given search display could be associated with either a single target location (standard contextual cueing) or two possible target locations. Our result showed that LTM-guided attention was always limited to only one target position in single- but also in the dual-target displays, as evidenced by expedited reaction times (RTs) and enhanced N1pc and N2pc deflections contralateral to one ("dominant") target of up to two repeating target locations. This contrasts with the processing of non-learned ("minor") target positions (in dual-target displays), which revealed slowed RTs alongside an initial N1pc "misguidance" signal that then vanished in the subsequent N2pc. This RT slowing was accompanied by enhanced N200 and N400 waveforms over fronto-central electrodes, suggesting that control mechanisms regulate the competition between dominant and minor targets. Our study thus reveals a dissociation in processing dominant versus minor targets: While LTM templates guide attention to dominant targets, minor targets necessitate control processes to overcome the automatic bias towards previously learned, dominant target locations.


Assuntos
Atenção , Sinais (Psicologia) , Eletroencefalografia , Potenciais Evocados , Tempo de Reação , Humanos , Atenção/fisiologia , Masculino , Feminino , Potenciais Evocados/fisiologia , Tempo de Reação/fisiologia , Adulto Jovem , Adulto , Eletroencefalografia/métodos , Percepção Visual/fisiologia , Estimulação Luminosa/métodos , Orientação/fisiologia , Memória de Longo Prazo/fisiologia
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