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Arterial spin labeling (ASL) imaging is a powerful magnetic resonance imaging technique that allows to quantitatively measure blood perfusion non-invasively, which has great potential for assessing tissue viability in various clinical settings. However, the clinical applications of ASL are currently limited by its low signal-to-noise ratio (SNR), limited spatial resolution, and long imaging time. In this work, we propose an unsupervised deep learning-based image denoising and reconstruction framework to improve the SNR and accelerate the imaging speed of high resolution ASL imaging. The unique feature of the proposed framework is that it does not require any prior training pairs but only the subject's own anatomical prior, such as T1-weighted images, as network input. The neural network was trained from scratch in the denoising or reconstruction process, with noisy images or sparely sampled k-space data as training labels. Performance of the proposed method was evaluated using in vivo experiment data obtained from 3 healthy subjects on a 3T MR scanner, using ASL images acquired with 44-min acquisition time as the ground truth. Both qualitative and quantitative analyses demonstrate the superior performance of the proposed txtc framework over the reference methods. In summary, our proposed unsupervised deep learning-based denoising and reconstruction framework can improve the image quality and accelerate the imaging speed of ASL imaging. 相似文献
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Previous event-related potential (ERP) studies show that a salient lateral sound activates the visual cortex more strongly contralateral to the sound, observed as an auditory-evoked contralateral occipital positivity (ACOP). Studies showed that this activation enhances the early cortical processing of co-localized visual stimuli presented after, reflected by better detection rates, better discrimination, and sharper perceived contrast. We replicated the ACOP, using earphones, and tested whether auditory cuing can influence temporal order judgments (TOJ) for two visual stimuli (horizontal arrangement) as well as if the ACOP would predict the amplitude of this influence. A lateral salient sound was followed, after 150 or 630 ms, by the visual presentation of a pair of disks, one in left and one in right hemifield, with variable SOA. The TOJ task was to indicate which disk appeared first or which disk appeared second (controlling for response bias). We observed an ACOP at posterior electrode sites and confirmed our hypothesis that the lateral sound influenced TOJ by accelerating the perception of the disk presented on the cued side, even though the sound was irrelevant to the task. Furthermore, the ACOP amplitude was correlated to this visual perceptual change, indicating that a larger change in brain activity was associated with a faster processing of co-localized visual stimuli. 相似文献
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《Research in social & administrative pharmacy》2022,18(2):2345-2349
This commentary looks at the process of conducting a systematic review of surveys and validated questionnaires. Surveys and other questionnaire style tools are often used in the field of social and administrative pharmacy, to capture beliefs, attitudes and experiences of patients and healthcare professionals (including pharmacists). Currently, there is little guidance available on how to conduct a systematic review of these types of studies. Considerations related to the process of a systematic review are highlighted, including identification of articles, data extraction, assessing quality of articles and synthesis and analysis of data. 相似文献
6.
AimTo examine the effectiveness of a Humanoid Diagram Teaching Strategy (HDTS) on care capabilities and retention of novice nurses.BackgroundGuiding novice nurses in clinical practice is a matter of concern and the use of diagrams in assisting the learning process and to promote learning efficiency has been acknowledged.DesignThis is a quasi-experimental study with asynchronous repeated measurements for the experimental and control groups.MethodsThe study was conducted in a medical centre in southern Taiwan with 24 novice nurses. The intervention, Humanoid Diagrams Teaching Strategy, contained three parts: the head and neck; trunk; and limbs. The HDTS was applied three time weekly. Each session lasted approximately 30 min and the training lasted 4 weeks. The effectiveness of HDTS was measured using Mini-CEX, CbD and retention rates in the 3rd and 6th months of novice nurses’ experience.ResultsAfter the HDTS, although increases in mini-CEX and CbD scores in the experimental group were greater than the control group, these differences were not statistically significant after considering the time interaction. But the 3rd month and 6th month novice nurses’ retention rates were statistically significantly different by comparing the differences under the time interaction effects in both groups.ConclusionsThe Humanoid Diagram Teaching Strategy is an effective tool for preceptors to use in assisting novice nurses in learning, improving their nursing care knowledge and technical skills and to increase their retention rate. 相似文献
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Loren Saulsberry PhD Ankur Bhargava MD MPH Sharon Zeng BA Jason B. Gibbons PhD Cody Brannan MS Diane S. Lauderdale PhD Robert D. Gibbons PhD 《Health services research》2023,58(4):873-881
Objective
To derive and validate a new ecological measure of the social determinants of health (SDoH), calculable at the zip code or county level.Data Sources and Study Setting
The most recent releases of secondary, publicly available data were collected from national U.S. health agencies as well as state and city public health departments.Study Design
The Social Vulnerability Metric (SVM) was constructed from U.S. zip-code level measures (2018) from survey data using multidimensional Item Response Theory and validated using outcomes including all-cause mortality (2016), COVID-19 vaccination (2021), and emergency department visits for asthma (2018). The SVM was also compared with the existing Centers for Disease Control and Prevention's Social Vulnerability Index (SVI) to determine convergent validity and differential predictive validity.Data Collection/Extraction Methods
The data were collected directly from published files available to the public online from national U.S. health agencies as well as state and city public health departments.Principal Findings
The correlation between SVM scores and national age-adjusted county all-cause mortality was r = 0.68. This correlation demonstrated the SVM's robust validity and outperformed the SVI with an almost four-fold increase in explained variance (46% vs. 12%). The SVM was also highly correlated (r ≥ 0.60) to zip-code level health outcomes for the state of California and city of Chicago.Conclusions
The SVM offers a measurement tool improving upon the performance of existing SDoH composite measures and has broad applicability to public health that may help in directing future policies and interventions. The SVM provides a single measure of SDoH that better quantifies associations with health outcomes. 相似文献8.
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《Patient education and counseling》2022,105(10):3123-3133
ObjectiveTo synthesize empowerment definitions in Parkinson’s disease (PD) literature and understand people with PD’s perspective on empowerment in the context of an existing empowerment conceptual model.MethodsThis mixed-methods study included a scoping review of PD empowerment literature and interviews with adults with PD. Five databases were searched for articles that defined empowerment concepts. We analyzed 1:1 semi-structured interviews on empowerment with people with PD. All data were analyzed using hybrid thematic analysis.ResultsEight of 242 records were included in this review. Empowerment is defined as an intrapersonal (e.g., personal control over oneself or healthcare) or interpersonal construct (e.g., person-centered care). Thirty-seven participants completed the interview. Participants perceived empowerment as a multifaceted concept that interacts with determinants and moderators from different ecological levels.ConclusionEmpowerment is a noteworthy multilevel and relational construct that can interplay with important health-related factors. The developed working conceptual model of empowerment can inform future studies to explore empowerment concepts in more depth and develop PD empowerment-based interventions.Practice implicationsThe empowerment definitions, indicators, determinants, and moderators identified in this study can help researchers, clinicians, and policymakers critically conceptualize empowerment and develop interventions to support people with PD. 相似文献
10.
Nakawala Lufumpa Anna Lavis Rishi Caleyachetty Michael Henry Sheena Kabombwe Semira Manaseki-Holland 《Maternal & child nutrition》2022,18(1):e13237
Child undernutrition is responsible for 45% of all under-five deaths in low- and middle-income countries (LMICs) and numerous morbidities. Although progress has been made, high levels of child undernutrition persist in Zambia. Existing studies have explored primary caretakers' (PCs) explanatory models of child undernutrition in LMICs, without comparison with those of health care providers (HCPs). This paper examines and compares the perceived causes of child undernutrition among PCs and HCPs in Zambia. We conducted a qualitative study, using semistructured one-to-one and group interviews, with 38 PCs and 10 HCPs to explore their perceptions of child undernutrition and its perceived causes in Lusaka district, Zambia. Interview data were analysed with thematic analysis. Our findings indicate that PCs and HCPs in Lusaka district have divergent explanatory models of child undernutrition and perceive parental agency differently. In divergently framing how they conceptualise undernutrition and who is able to prevent it, these models underpin different attributions of causality and different opportunities for intervention. PCs highlighted factors such as child food preferences, child health, and household finances. Contrarily, HCPs stressed factors such as ‘improper feeding’, only highlighting factors such as wider economic conditions when these impacted specifically on health care services. One factor, identified by both groups, was ‘inadequate mothering’. To accelerate the reduction of child undernutrition, interventions must address divergences between PCs and HCPs' explanatory models. Additionally, attention needs to be paid to how wider socio-economic and cultural contexts not only impact childhood undernutrition but shape attributions of causality. 相似文献