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Objective: To analyze CT and MRI imaging features of adrenocortical carcinoma (ACC). Methods: A retrospective analysis was conducted on the CT, MRI plain and contrast-enhanced imaging manifestations and clinical data of 39 ACC patients,and all were confirmed by surgery and pathological examination. The imaging features with significant diagnostic value for ACC were summarized, and the value of two imaging techniques for the diagnosis of ACC was explored. Results: Fourteen patients underwent both CT and MRI plain and enhanced examinations, while 22 patients underwent CT plain and enhanced examinations, and 3 patients underwent MRI examination only. Among the 39 ACC patients, 38 tumors were unilateral (19 on the left and 19 on the right), and 1 tumor was bilateral; twenty-three cases of tumors were lobulated, while 16 cases were quasi circular; the diameter of the tumor ranged from 4.0 to 17.3 cm. In CT and MRI examinations, intralesional hemorrhage was found in 47.2% and 82.4% of cases; thickened and tortuous tumor vasculature were found in 91.7% and 50% of cases; irregular capsule was found in 77.8% and 82.4% of cases. All tumors showed heterogeneous enhancement, and most of the solid components of the tumor showed moderate enhancement; a small number of cases showed calcification, involvement of surrounding organs and blood vessels, retroperitoneal lymph nodes, and distant metastasis. Among the 14 cases who completed both CT and MRI plain and enhanced examinations, 6 and 12 cases with hemorrhage of tumor, 12 and 6 cases with tumor vasculature, and 9 and 12 cases with capsule irregularities, were found respectively. Conclusions: The manifestations of CT and MRI have certain characteristics in ACC patients. Most ACCs tend to be large (diameter more than 4 cm), lobulated, and tumor vasculature, with areas of hemorrhage and necrosis, capsule irregularities, and heterogeneous enhancement. CT has advantages in evaluating tumor vasculature over MRI, while MRI has advantages in displaying intralesional hemorrhage over CT.

Attosecond probing of core-level electronic transitions provides a sensitive tool for studying valence molecular dynamics with atomic, state, and charge specificity. In this report, we employ attosecond transient absorption spectroscopy to follow the valence dynamics of strong-field initiated processes in methyl bromide. By probing the 3d core-to-valence transition, we resolve the strong field excitation and ensuing fragmentation of the neutral σ* excited states of methyl bromide. The results provide a clear signature of the non-adiabatic passage of the excited state wavepacket through a conical intersection. We additionally observe competing, strong field initiated processes arising in both the ground state and ionized molecule corresponding to vibrational and spin-orbit motion, respectively. The demonstrated ability to resolve simultaneous dynamics with few-femtosecond resolution presents a clear path forward in the implementation of attosecond XUV spectroscopy as a general tool for probing competing and complex molecular phenomena with unmatched temporal resolution.

Objective: To evaluate value of blood oxygen level-dependent (BOLD) magnetic resonance imaging (MRI) for early renal hypoxia assessment in chronic kidney disease(CKD). Methods: Fifty-two patients with CKD and 52 age- and sex-matched health volunteers underwent BOLD MRI of the kidneys. Serum creatinine (sCr) levels and estimated GFR (eGFR) were collected. The patients were classified into 5 stages according to the National Kidney Foundation′s Kidney Disease Outcomes Quality Initiative. Difference in R2*s were compared between patients and volunteers and among different stages of CKD. Results: In patients with CKD and volunteers, R2* of renal medulla was higher than that of renal cortex (P0.05). However, medullar R2*s were lower in patients with CKD1 [(16.55 ± 2.12)/s], CKD4 [(16.48 ± 2.95)/s], or CKD5 [(13.99 ± 2.21)/s] than those in volunteers [(18.17± 2.38)/s] (P

The stability of gas-fired flame is studied by combining the optical flow method and deep learning. The optical flow vector of the flame image is directly calculated by using the optical flow method. The pulsation of the flame in the two-dimensional image is observed, and an optical flow pulsation evaluation model is proposed to evaluate the stability of the flame. In addition, a deep convolutional neural network based on VGG-Nets is built and fine adjustments are made on ImageNet pre-training weights. Combining the static and dynamic characteristics of flames, the classification and recognition of five typical combustion states are achieved. The results show that this method has a good judgment ability for different combustion states of flames and a high recognition rate for unstable combustion flames.

Nb2O5/TiO2 composite coatings were prepared in sodium silicate electrolyte, and the high-temperature oxidation properties of the coatings were improved. SEM showed that the number of micro-pores on the surface of the coatings decreased, and the content of Nb2O5 increased from 0 to 9.45% with the increase in Nb2O5 concentration. The coatings comprised O, Na, Al, Si, P, K, Ti, and Nb. Nb entered and was uniformly distributed in the coatings, and its content increased from 0 to 13.76%. Meanwhile, the thickness of the coatings increased from 29.57 to 43.27 µm. The coatings comprised anatase-TiO2, rutile-TiO2, Nb2O5, and Al2TiO5. The valence of Nb was assigned to Nb2O5 and NbxOy. The average oxidation rate decreased from 2.4333 × 10−5 to 2.8056 × 10−6 mg cm−2 s−1. Nb2O5 in the coatings hindered the high-temperature oxidation process and improved the high-temperature properties of the coatings. [ABSTRACT FROM AUTHOR]

Profiling gene expression while preserving cell locations aids in the comprehensive understanding of cell fates in multicellular organisms. However, simple and flexible isolation of microregions of interest (mROIs) for spatial transcriptomics is still challenging. We present a laser-induced forward transfer (LIFT)-based method combined with a full-length mRNA-sequencing protocol (LIFT-seq) for profiling region-specific tissues. LIFT-seq demonstrated that mROIs from two adjacent sections could reliably and sensitively detect and display gene expression. In addition, LIFT-seq can identify region-specific mROIs in the mouse cortex and hippocampus. Finally, LIFT-seq identified marker genes in different layers of the cortex with very similar expression patterns. These genes were then validated using in situ hybridization (ISH) results. Therefore, LIFT-seq will be a valuable and efficient technique for profiling the spatial transcriptome in various tissues. [ABSTRACT FROM AUTHOR]

Background: Although white matter hyperintensity (WMH) is closely associated with cognitive decline, the precise neurobiological mechanisms underlying this relationship are not fully elucidated. Connectome studies have identified a primary‐to‐transmodal gradient in functional brain networks that support the spectrum from sensation to cognition. However, whether connectome gradient structure is altered as WMH progresses and how this alteration is associated with WMH‐related cognitive decline remain unknown. Methods: A total of 758 WMH individuals completed cognitive assessment and resting‐state functional MRI (rs‐fMRI). The functional connectome gradient was reconstructed based on rs‐fMRI by using a gradient decomposition framework. Interrelations among the spatial distribution of WMH, functional gradient measures, and specific cognitive domains were explored. Results: As the WMH volume increased, the executive function (r = −0.135, p = 0.001) and information‐processing speed (r = −0.224, p = 0.001) became poorer, the gradient range (r = −0.099, p = 0.006), and variance (r = −0.121, p < 0.001) of the primary‐to‐transmodal gradient reduced. A narrower gradient range (r = 0.131, p = 0.001) and a smaller gradient variance (r = 0.136, p = 0.001) corresponded to a poorer executive function. In particular, the relationship between the frontal/occipital WMH and executive function was partly mediated by gradient range/variance of the primary‐to‐transmodal gradient. Conclusions: These findings indicated that WMH volume, the primary‐to‐transmodal gradient, and cognition were interrelated. The detrimental effect of the frontal/occipital WMH on executive function was partly mediated by the decreased differentiation of the connectivity pattern between the primary and transmodal areas. [ABSTRACT FROM AUTHOR]

Aims: Synaptic dysfunction is a hallmark pathology of Alzheimer's disease (AD) and is strongly associated with cognitive impairment. Abnormal phagocytosis by the microglia is one of the main causes of synapse loss in AD. Previous studies have shown that the absence of melanoma 2 (AIM2) inflammasome activity is increased in the hippocampus of APP/PS1 mice, but the role of AIM2 in AD remains unclear. Methods: Injection of Aβ1‐42 into the bilateral hippocampal CA1 was used to mimic an AD mouse model (AD mice). C57BL/6 mice injected with AIM2 overexpression lentivirus and conditional knockout of microglial AIM2 mice were used to confirm the function of AIM2 in AD. Cognitive functions were assessed with novel object recognition and Morris water maze tests. The protein and mRNA expression levels were evaluated by western blotting, immunofluorescence staining, and qRT‐PCR. Synaptic structure and function were detected by Golgi staining and electrophysiology. Results: The expression level of AIM2 was increased in AD mice, and overexpression of AIM2 induced synaptic and cognitive impairments in C57BL/6 mice, similar to AD mice. Elevated expression levels of AIM2 occurred in microglia in AD mice. Conditional knockout of microglial AIM2 rescued cognitive and synaptic dysfunction in AD mice. Excessive microglial phagocytosis activity of synapses was decreased after knockout of microglial AIM2, which was associated with inhibiting complement activation. Conclusion: Our results demonstrated that microglial AIM2 plays a critical role in regulating synaptic plasticity and memory deficits associated with AD, providing a new direction for developing novel preventative and therapeutic interventions for this disease. [ABSTRACT FROM AUTHOR]