Nonfullerene acceptors (NFAs) have attracted great attention in high-efficiency organic solar cells (OSCs). While the effect of molecular properties including structures and energetics on charge ...transfer has been extensively investigated, the effect of macroscopic-phase properties is yet to be revealed. Here we have performed a correlation study of the nanoscale-phase morphology on the photoexcited hole transfer (HT) process and photovoltaic performance by combining ultrafast spectroscopy with high temporal resolution and photo-induced force microscopy (PiFM) with high spatial and chemical resolution. In PM6/IT-4F, we observe biphasic HT behavior with a minor ultrafast (<100 fs) interfacial process and a major diffusion-mediated HT process until ∼100 ps, which depends strongly on phase segregation. Because of the interplay between charge transfer and transport, a compromised domain size of 20–30 nm for NFAs shows the best performance. This study highlights the critical role of phase morphology in high-efficiency OSCs.
In this paper, we propose an optimization algorithm for RIS-assisted multiple-input single-output vehicle communication systems, Given a vehicle-to-vehicle user signal to interference plus noise ...ratio requirement, we optimize the transmit beamforming vector and phase shift matrix of RIS to obtain the maximum transmission rate of vehicle to infrastructure user. To deal with the coupled variables in the optimization problem, the alternate iterative algorithm is exploited to divide the original optimization problem into two sub-problems, each with a single variable. Moreover, the first-order Taylor expansion and the semidefinite relaxation methods are used to transform the nonconvex sub-problems into convex optimization problems. The simulation results are presented to validate the superiority of the proposed method compared to the benchmark schemes. Additionally, the simulation results also reveal that there exits an optimal vehicle speed under different path loss exponents so as to achieve the maximum transmission rate if the RIS is used by our proposed beamforming method.
Objective
We aimed to characterize the potential risk factors and cerebral perfusion of patients with subjective cognitive decline (SCD).
Methods
This prospective study enrolled consecutive patients ...from the Chinese Imaging, Biomarkers, and Lifestyle (CIBL) Cohort of Alzheimer’s disease between February 2021 and March 2022. Patients who met the SCD diagnostic criteria were categorized into the SCD group, while those without cognitive complaints or any concerns were assigned to the healthy control (HC) group. The demographic and clinical characteristics and cerebral blood flow (CBF) from pseudo-continuous arterial spin labeling (pCASL) in standard cognitive regions were compared between these two groups. A multivariate analysis was performed to identify independent factors associated with SCD.
Results
The frequency of family history of dementia in the SCD group was higher compared with the HC group (
p
= 0.016). The CBF of left hippocampus (
p
= 0.023), left parahippocampal gyrus (
p
= 0.004), left precuneus (
p
= 0.029), left middle temporal gyrus (
p
= 0.022), right parahippocampal gyrus (
p
= 0.018), and right precuneus (
p
= 0.024) in the SCD group were significantly increased than those in the HC group. The multivariate logistic regression analyses demonstrated that the family history of dementia
OR
= 4.284 (1.096–16.747),
p
= 0.036 and the CBF of left parahippocampal gyrus
OR
= 1.361 (1.006–1.840),
p
= 0.045 were independently associated with SCD.
Conclusion
This study demonstrated that the family history of dementia and the higher CBF within the left parahippocampal gyrus were independent risk factors associated with patients with SCD, which could help in the early identification of the SCD and in intervening during this optimal period.
Background:
Plasma-based biomarkers would be potential biomarkers for early diagnosis of Alzheimer's disease (AD) because they are more available and cost-effective than cerebrospinal fluid (CSF) or ...neuroimaging. Therefore, we aimed to evaluate whether phosphorylated tau181 (p-tau181) in plasma could be an accurate AD predictor.
Methods:
Participants from the ADNI database included 185 cognitively unimpaired subjects with negative Aβ (CU–), 66 subjects with pre-clinical AD (CU with positive Aβ), 164 subjects with mild cognitive impairment with negative Aβ (MCI–), 254 subjects with prodromal AD (MCI with positive Aβ), and 98 subjects with dementia. Multiple linear regression models, linear mixed-effects models, and local regression were used to explore cross-sectional and longitudinal associations of plasma p-tau181 with cognition, neuroimaging, or CSF biomarkers adjusted for age, sex, education, and APOE genotype. Besides, Kaplan–Meier and adjusted Cox-regression model were performed to predict the risk of progression to dementia. Receiver operating characteristic analyses were performed to evaluate the predictive value of p-tau181.
Results:
Plasma p-tau181 level was highest in AD dementia, followed by prodromal AD and pre-clinical AD. In pre-clinical AD, plasma p-tau181 was negatively associated with hippocampal volume (β = −0.031,
p
-value = 0.017). In prodromal AD, plasma p-tau181 was associated with decreased global cognition, executive function, memory, language, and visuospatial functioning (β range −0.119 to −0.273,
p
-value < 0.05) and correlated with hippocampal volume (β = −0.028,
p
-value < 0.005) and white matter hyperintensity volume (WMH) volume (β = 0.02,
p
-value = 0.01). In AD dementia, increased plasma p-tau181 was associated with worse memory. In the whole group, baseline plasma p-tau181 was significantly associated with longitudinal increases in multiple neuropsychological test
z
-scores and correlated with AD-related CSF biomarkers and hippocampal volume (
p
-value < 0.05). Meanwhile, CU or MCI with high plasma p-tau181 carried a higher risk of progression to dementia. The area under the curve (AUC) of the adjusted model (age, sex, education, APOE genotype, and plasma p-tau181) was 0.78; that of additionally included CSF biomarkers was 0.84.
Conclusions:
Plasma p-tau181 level is related to multiple AD-associated cognitive domains and AD-related CSF biomarkers at the clinical stages of AD. Moreover, plasma p-tau181 level is related to the change rates of cognitive decline and hippocampal atrophy. Thus, this study confirms the utility of plasma p-tau181 as a non-invasive biomarker for early detection and prediction of AD.
The difficulty in pathological image diagnosis of gastric cancer lies in the accurate segmentation of cancerous tissue in the picture. To increase gastric cancer pathological images segmentation ...accuracy, we optimized the basic UNet model and proposed the DCU-Net model. First, add a direct channel module to each layer of the encoding part to obtain more detailed information. In addition, considering that the image may cause a loss of information during the transmission process, a CA module is added before the up-sampling and down-sampling of each layer so that the model can obtain more channel information. After conducting segmentation experiments on our own gastric cancer data set and comparing it with several current classic segmentation models. The experiment proved that the segmentation accuracy using this article's model can be enhanced on our own gastric cancer image segmentation data set, achieving an accuracy of 91.30% and an IoU of 79.88%.
This article proposes an improved YOLOv5s counting method to address the problems of long-term manual counting of positive cells in immunohistochemical images and low consistency. First, by ...introducing the Triplet attention module, the model focuses on the positive cell area, reducing background interference and improving the network's ability to extract positive cell features; then, a small target detection layer is added to better utilize the semantic information of the network to improve positive cells. recognition accuracy; then, the lightweight up-sampling operator CARAFE is used to improve the quality and accuracy of up-sampling; finally, the WIoU loss function is used to replace the original GIoU of YOLOv5 to enhance model detection performance. Experimental results show that the improved model has an average accuracy of 88.4%, which is 3.1% higher than the original YOLOv5 network model. It can count positive cells quickly and accurately, reducing the workload of doctors.
Background
Cerebral blood flow (CBF) alterations are involved in the onset and progression of Alzheimer’s disease (AD) and can be a potential biomarker. However, CBF measured by single-delay arterial ...spin labeling (ASL) for discrimination of mild cognitive impairment (MCI, an early stage of AD) was lack of accuracy. Multi-delay ASL can not only provide CBF quantification but also provide arterial transit time (ATT). Unfortunately, the technique was scarcely applied to the diagnosis of AD. Here, we detected the utility of ASL with 1-delay and 7-delay in ten regions of interest (ROIs) to identify MCI and AD.
Materials and Methods
Pseudocontinuous ASL (pCASL) MRI was acquired on a 3T GE scanner in adults from the Chinese Imaging, Biomarkers, and Lifestyle (CIBL) Study of AD cohort, including 26 normal cognition (NC), 37 MCI, and 39 AD. Receiver operating characteristic (ROC) analyses with 1-delay and 7-delay ASL were performed for the identification of MCI and AD. The DeLong test was used to compare ROC curves.
Results
For CBF of 1-delay or 7-delay the AUCs showed moderate-high performance for the AD/NC and AD/MCI comparisons (AUC = 0.83∼0.96) (
p
< 0.001). CBF of 1-delay performed poorly in MCI/NC comparison (AUC = 0.69) (
p
< 0.001), but CBF of 7-delay fared well with an AUC of 0.79 (
p
< 0.001). The combination of CBF and ATT of 7-delay showed higher performance for AD/NC, AD/MCI, and MCI/NC comparisons with AUCs of 0.96, 0.89, and 0.89, respectively (
p
< 0.001). Furthermore, combination of CBF, ATT, sex, age,
APOE
ε4, and education improved further the accuracy (
p
< 0.001). In subgroups analyses, there were no significant differences in CBF of 7-delay ASL for identification of AD or MCI between age subgroups (
p
> 0.05).
Conclusion
The combination of CBF and ATT with 7-delay ASL showed higher performance for identification of MCI than CBF of 1-delay, when adding to sex, age,
APOE
ε4 carrier status, and education years, the diagnostic performance was further increased, presenting a potential imaging biomarker in early AD.
The potential correlation between patent foramen ovale (PFO) and migraine has been previously reported, but whether PFO closure plays a role in reducing migraine burden has not reached an agreement.
...We searched PubMed, Embase, China National Knowledge Infrastructure (CNKI), Wanfang Database, VIP Science Technology Periodical Database and China Biology Medicine Database (CBM) through September 30, 2021 to identify associations between PFO closure and outcome of migraine burden. The control groups consisted of drug treatment or sham procedure.
Three randomized clinical trials (RCT) and 9 case-control studies were eligible for inclusion (1754 participants), of which 7 reported nonrecurrence of migraine, 4 reported reduced migraine-frequency and migraine-days, and 5 reported HIT-6 score and 4 reported MIDAS score. The mean (SD) age of participants was 40.68 (3.81) years and 1340 (76.39%) were women. PFO closure was significantly associated with a reduced risk of migraine-recurrence by 4.47 (95% CI, 2.94–6.80; I2 = 12%), frequency of migraine by 0.35 (95% CI, 0.17–0.53; I2 = 0%) and monthly migraine days by 0.28 (95% CI, 0.10–0.46), and decreased score of HIT-6 (SMD 1.23, 95 %CI 0.52–1.95, I2 = 93%).
Transcatheter PFO closure is significantly associated with burden reduction of migraine headache.
Background:
Depression is common in Alzheimer's disease (AD) with an unclear neural mechanism. This study aimed to investigate the underlying cerebral perfusion associated with depression in AD and ...evaluate its clinical significance.
Method:
Twenty-one AD patients and 21 healthy controls (HCs) were enrolled in this study. The depressive symptom was defined according to the Hamilton Depression Rating Scale (HAMD). Nine patients were diagnosed as AD with depression symptoms (HAMD >7). Three-dimensional pseudocontinuous arterial spin labeling MR imaging was conducted to measure regional cerebral blood flow (CBF). Neuropsychological tests covered cognition and depressive scores. Between-group comparisons on clinical variables and regional CBFs, relationship between regional CBF and depressive score, and identification of AD patients with depression were performed using covariance analysis, linear regression, and receiver operating characteristic (ROC) analysis, respectively.
Results:
Compared with HCs, AD patients without depression exhibited lower gray matter CBF (
p
= 0.016); compared with AD patients without depression, AD patients with depression had higher CBF in the right supplementary motor area (39.23 vs. 47.91 ml/100 g/min,
p
= 0.017) and right supramarginal gyrus (35.54 vs. 43.85 ml/100 g/min,
p
= 0.034). CBF in the right supplementary motor area was correlated with depressive score (β = 0.46,
p
= 0.025). The combination of CBF in the right supplementary motor area and supramarginal gyrus and age could identify AD patients with depression from those without depression with a specificity of 100%, sensitivity of 66.67%, accuracy of 85.71%, and area under the curve of 0.87.
Conclusions:
Our findings suggested that hyperperfusion of the right supplementary motor area and right supramarginal gyrus were associated with depression syndrome in AD, which could provide a potential neuroimaging marker to evaluate the depression state in AD.
Background
The ε4 allele of the apolipoprotein E (APOE) gene is a strong genetic risk factor for aging-related cognitive decline. However, the causal connection between ε4 alleles and cognition is ...not well understood. The objective of this study was to identify the roles of cerebral blood flow (CBF) in cognitive-related brain areas in mediating the associations of APOE with cognition.
Methods
The multiple linear regression analyses were conducted on 369 subjects (mean age of 68.8 years; 62.9% of women; 29.3% of APOE ε4 allele carriers). Causal mediation analyses with 5,000 bootstrapped iterations were conducted to explore the mediation effects.
Result
APOE ε4 allele was negatively associated with cognition (
P
< 0.05) and CBF in the amygdala, hippocampus, middle temporal gyrus, posterior cingulate, and precuneus (all
P
< 0.05). The effect of the APOE genotype on cognition was partly mediated by the above CBF (all
P
< 0.05).
Conclusion
CBF partially mediates the potential links between APOE genotype and cognition. Overall, the APOE ε4 allele may lead to a dysregulation of the vascular structure and function with reduced cerebral perfusion, which in turn leads to cognitive impairment.
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