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Vascular mild cognitive impairment (VMCI) is an early and reversible stage of dementia. Volume differences in regional gray matter may reveal the development and prognosis of VMCI. This study selected 2 of the most common types of VMCI, namely, periventricular white matter hyperintensities (PWMH, n = 14) and strategic single infarctions (SSI, n = 10), and used the voxel-based morphometry method to quantify their morphological characteristics. Meanwhile, age- and sex-matched healthy volunteers were included (n = 16). All the participants were neuropsychologically tested to characterize their cognitive function and underwent whole-brain magnetic resonance imaging scanning. Our results showed that the volumes of the bilateral temporal lobes and bilateral frontal gray matter were obviously diminished in the PWMH group. The atrophy volume difference was 4,086 voxels in the left temporal lobe, 4,154 voxels in the right temporal lobe, 1,718 voxels in the left frontal lobe, and 1,141 voxels in the right frontal lobe (P ≤ 0.001). Moreover, the characteristics of the gray matter atrophy associated with the PWMH were more similar to those associated with Alzheimer’s disease than SSI, which further revealed the susceptibility for escalation from PWMH to dementia. In conclusion, PWMH patients and SSI patients have different morphological characteristics, which explain the different prognoses of VMCI.

To balance the phase output currents of a multi- phase inverter, negatively coupled inductors (NCIs) can be used to achieve a larger differential mode (DM) loop impedance than the common mode (CM) loop impedance. For a good current sharing effect, the inductances of the NCIs should be large, leading to bulky size and cost ineffectiveness, which should be avoided in high-power applications. This paper proposes a novel current balancing method based on parallel resonance. A parallel resonant network (PRN) is inserted between any two phases. With -Y transform, the inductor common point and the capacitor common point are generated, either of which can be used as the CM output node. For a series-series compensated wireless power transfer system, part of the existing compensating capacitance can be employed to form PRNs with the added paralleling inductors. The DM currents are suppressed by the large impedance of the PRNs. Compared with the existing method, the inductances of the NCIs can be greatly reduced to achieve better current balancing performance. The added paralleling inductors are of small current ratings, which are only visible to DM currents. A prototype is implemented to validate the proposed method.

This paper proposes a novel WOA-based robust control scheme with two kinds of propagation latencies and external disturbance implemented in Software-Defined Wireless Networks (SDWNs) to maximize overall throughput and enhance the stability of the global network. Firstly, an adjustment model developed using the Additive-Increase Multiplicative-Decrease (AIMD) adjustment scheme with propagation latency in device-to-device paths and a closed-loop congestion control model with propagation latency in device–controller pairs are proposed, and the effect of channel competition from neighboring forwarding devices is analyzed. Subsequently, a robust congestion control model with two kinds of propagation latencies and external disturbance is established. Then, a new WOA-based scheduling strategy that considers each individual whale as a specific scheduling plan to allocate appropriate sending rates at the source side is presented to maximize the global network throughput. Afterward, the sufficient conditions are derived using Lyapunov–Krasovskii functionals and formulated using Linear Matrix Inequalities (LMIs). Finally, a numerical simulation is conducted to verify the effectiveness of this proposed scheme.

To establish and validate a CT radiomics model for prediction of induction chemotherapy (IC) response and progression-free survival (PFS) among patients with locally advanced hypopharyngeal carcinoma (LAHC).One hundred twelve patients with LAHC (78 in training cohort and 34 in validation cohort) who underwent contrast-enhanced CT (CECT) scans prior to IC were enrolled. Least absolute shrinkage and selection operator (LASSO) was used to select the crucial radiomic features in the training cohort. Radiomics signature and clinical data were used to build a radiomics nomogram to predict individual response to IC. Kaplan-Meier analysis and log-rank test were used to evaluate ability of radiomics signature in progression-free survival risk stratification.The radiomics signature consisted of 6 selected features from the arterial and venous phases of CECT images and demonstrated good performance in predicting the IC response in both two cohorts. The radiomics nomogram showed good discriminative performance, and the C-index of nomogram was 0.899 (95% confidence interval (CI), 0.831-0.967) and 0.775 (95% CI, 0.591-0.959) in the training and validation cohorts, respectively. Survival analysis indicated that low-risk and high-risk groups defined by the value of radiomics signature had significant difference in PFS (3-year PFS 66.4% vs 29.7%, p0.001).Multiparametric CT-based radiomics model could be useful for predicting treatment response and PFS in patients with LAHC who underwent IC.• CT radiomics can predict IC response and progression-free survival in hypopharyngeal carcinoma. • We combined significant radiomics signature with clinical predictors to establish a nomogram to predict individual response to IC. • Radiomics signature could divide patients into the high-risk and low-risk groups based on the PFS.

ObjectivesTo compare the signal alterations of amide proton transfer (APT), apparent diffusion coefficient (ADC), and fractional anisotropy (FA) in white matter (WM) lesions in multiple sclerosis (MS), compared with healthy controls (HCs), and to investigate the relationships between these changes and clinical measurements such as serum neurofilament light chain (sNfL).Materials and methodsTwenty-nine patients with relapsing-remitting MS (21 females and 8 males) and 30 HCs (23 females and 7 males) were recruited. APT-weighted (APTw) and diffusion tensor imaging (DTI) data were acquired using a 3.0-T magnetic resonance system. APTw and DTI images were registered to FLAIR-SPIR images and assessed by two neuroradiologists. MTRasym (3.5 ppm), ADC, FA values for MS and HC are calculated using mean values from all regions of interest (ROI). The ROI criteria were: (1) for MS patients, ROI were defined as MS lesions, and each lesion was identified. (2) The WM around each HC’s lateral ventricle (frontal lobe, parietal lobe, and centrum semiovale) was assessed bilaterally. The diagnostic efficacy of MTRasym (3.5 ppm), ADC, and FA in the lesions of MS patients was compared using receiver operating characteristic (ROC) curve analysis. The associations between MTRasym (3.5 ppm), ADC, and FA values and the clinical measurements were investigated further.ResultsThe MTRasym (3.5 ppm) and ADC values of brain lesions were increased, while FA values were decreased in patients with MS. The diagnostic area under curve (AUC) of MTRasym (3.5 ppm), ADC, and FA value was 0.891 (95% CI: 0.813, 0.970), 0.761 (95% CI: 0.647, 0.875) and 0.970 (95% CI: 0.924, 1.0), respectively. sNfL was considerably positively correlated with MTRasym (3.5 ppm) (P = 0.043, R = 0.38) and disease durations were significantly negatively correlated with FA (P = 0.046, R = −0.37).ConclusionAmide proton transfer-weighted (APTw) and DTI are potential imaging methods for assessing brain lesions in patients with MS at the molecular and microscopic levels, respectively. The association between APTw, DTI parameters and clinical factors implies that they may play a role in disease damage monitoring.

Background. Chemical exchange saturation transfer (CEST) is a novel imaging modality in clinical practice and scientific research. Angiopep-2 is an artificial peptide that can penetrate blood-brain barrier. The aim of this study was to explore the feasibility of Angiopep-2 serving as an exogenous CEST contrast. Methods. Phantoms of Angiopep-2 with different concentrations were prepared and then scanned using the 7.0T small animal MRI scanner. Different parameters including saturation powers and saturation duration were used to achieve the optimal CEST effect, and the optimal parameters were finally selected based on Z-spectra, asymmetric spectra, and phantom CEST imaging. CEST scanning of dimethyl sulfoxide (DMSO), the substance helping Angiopep-2 to be dissolved in water, was performed to exclude its contribution for the CEST effect. Results. A broad dip was observed from 2.5 to 3.5 ppm in the Z-spectra of Angiopep-2 phantoms. The most robust CEST was generated at 3.2 ppm when using formula (M–3.2ppm − M+3.2ppm)/M–3.2ppm. The CEST effect of Angiopep-2 was concentration dependent; the effect increased as the concentration increased. In addition, the CEST effect was more obvious as the saturation power increased and peaked at 5.5 µT, and the CEST effect increased as the saturation duration increased. DMSO showed nearly 0% of the CEST effect at 3.2 ppm. Conclusions. Our results demonstrate that Angiopep-2 can act as an excellent exogenous CEST contrast. As it can penetrate blood-brain barrier and bind amyloid-β protein, amyloid-β targeting CEST, with Angiopep-2 as an exogenous contrast agent, can be potentially used as a novel imaging modality for early diagnosis of Alzheimer’s disease. Collectively, Angiopep-2 may play a critical role in early diagnosis of Alzheimer’s disease.

Background: The recently released Myeloma Response Assessment and Diagnosis System (MY-RADS) for multiple myeloma (MM) evaluation by whole-body MRI (WB-MRI) describes the total burden score. However, assessment is confounded by red bone marrow hyperplasia in anemia. Objective: To assess utility of the MY-RADS total burden score, ADC, and fat fraction (FF) from WB-MRI in predicting early treatment response in patients with newly diagnosed MM and to compare these measures' utility between patients with and without anemia. Methods: This retrospective study included 56 patients (mean age 57.4±9.6 years; 40 men, 16 women) with newly diagnosed MM who underwent baseline WB-MRI including DWI and mDixon sequences. Two radiologists recorded total burden score using MY-RADS and measured ADC and FF of diffuse and focal disease sites. Mean values across sites were derived. Interobserver agreement was evaluated; readers' mean assessments were used for further analyses. Presence of deep response after four cycles of induction chemotherapy was recorded. Patients were classified as anemic if having hemoglobin less than 100 g/L. Utility of WB-MRI parameters in predicting deep response was assessed. Results: A total of 24/56 patients showed deep response; a total of 25/56 patients had anemia. Interobserver agreement, expressed using intraclass correlation coefficients, ranged from 0.95 to 0.99. Among patients without anemia, those with deep response compared with those without deep response exhibited lower total burden score (9.0 vs 18.0), lower ADC (0.79x10-3mm2/s vs 1.08x10-3mm2/s), and higher FF (0.21 vs 0.10) (all p 0.16 for FF) achieved sensitivity of 93.8%, specificity of 93.3%, and accuracy of 93.5% for predicting deep response. In patients with anemia, none of the three parameters were significantly different between those with and without deep response (all p>.05), and the combination of parameters achieved sensitivity of 56.3%, specificity of 100.0%, and accuracy of 72.0%. Conclusion: Low total burden score, low ADC, and high FF from WB-MRI may predict deep response in MM, though only among those patients without anemia. Clinical Impact: WB-MRI findings may help guide determination of prognosis and initial treatment selection in MM.

To explore the value of amide proton transfer-weighted (APTw) magnetic resonance imaging (MRI) for differential diagnosis of fibroadenomas and malignant breast tumors.This prospective study enrolled 56 patients with suspected breast tumors and performed APTw imaging. Based on the histopathology results, patients were divided into group 1 with malignant breast tumors (n = 41) and group 2 with fibroadenomas (n = 15). The measured image parameters (APTw value, ADC value, type of Time of Intensity Curve, maximum tumor diameter in image) and the maximal diameter of the tumors measured from surgical resection were compared between the two groups, and the diagnostic performance based on these parameters was quantified with ROC curve. Spearman's correlation coefficient was used to analyze the association between APTw or ADC values and ER, PR, HER2, and Ki-67 expressions.The intraclass correlation coefficients (ICC = 0.87 and 0.91) indicated a good inter-observer agreement of the measured APTw values. APTw values of malignant lesions were significantly higher than those of fibroadenomas (3.21 ± 1.04% vs 1.50 ± 0.54%, p 0.001). Area under the curve (AUC) obtained from APTw imaging, DWI, DCE, APTw imaging+DWI, APTw imaging+DWI, and APTw imaging+DWI + DCE was 0.959, 0.897, 0.976, 0.997, and 1 respectively. The APTw value showed a negative correlation with ER expression (r = -0.357).APTw imaging yielded similar diagnosis performance in discriminating fibroadenomas and malignant breast tumors when compared to the DCE and better than DWI imaging, and provided supplement information on tumor cell activity to DWI images. The APTw value showed correlations with some prognostic factors for breast cancer.

Sleep deprivation leads to hippocampal injury. Proteostasis disturbance is an important mechanism linking sleep deprivation and hippocampal injury. However, identifying noninvasive imaging biomarkers for hippocampal proteostasis disturbance remains challenging. Amide proton transfer-weighted (APTw) imaging is a chemical exchange saturation transfer technique based on the amide protons in proteins and peptides. We aimed to explore the ability of APTw imaging in detecting sleep deprivation-induced hippocampal proteostasis disturbance and its biological significance, as well as its biological basis. In vitro, the feasibility of APTw imaging in detecting changes of the protein state was evaluated, demonstrating that APTw imaging can detect alterations in the protein concentration, conformation, and aggregation state. In vivo, the hippocampal APTw signal declined with increased sleep deprivation time and was significantly lower in sleep-deprived rats than that in normal rats. This signal was positively correlated with the number of surviving neurons counted in Nissl staining and negatively correlated with the expression of glucose-regulated protein 78 evaluated in immunohistochemistry. Differentially expressed proteins in proteostasis network pathways were identified in the hippocampi of normal rats and sleep-deprived rats via mass spectrometry proteomics analysis, providing the biological basis for the change of the hippocampal APTw signal in sleep-deprived rats. These findings demonstrate that APTw imaging can detect hippocampal proteostasis disturbance induced by sleep deprivation and reflect the extent of neuronal injury and endoplasmic reticulum stress.

Wireless power transfer (WPT) for electric vehicles is an emerging technology and a future trend. To increase power density, the coupling coefficient of coils can be designed to be large, forming a strongly coupled WPT system, different from the conventional loosely coupled WPT system. In this way, the power density and efficiency of the WPT system can be improved. This paper investigates the dual-side phase-shift control of the strongly coupled series–series compensated WPT systems. The mathematical models based on the conventional first harmonic approximation and differential equations for the dual-side phase-shift control are built and compared. The dual-side phase-shift angle and its impact on the power transfer direction and soft switching are investigated. It is found that synchronous rectification at strong couplings can lead to hard switching because the dual-side phase shift in this case is over 90°. In comparison, a relatively high efficiency and soft switching can be realized when the dual-side phase shift is below 90°. The experimental results have validated the analysis.

Valence fluctuation of interacting electrons plays a crucial role in emergent quantum phenomena in correlated electron systems. The theoretical rationale is that this effect can drive a band insulator into a superconductor through charge redistribution around the Fermi level. However, the root cause of such a fluctuating leap in the ionic valency remains elusive. Here, we demonstrate a valence-skipping-driven insulator-to-superconductor transition and realize quasi-two-dimensional superconductivity in a van der Waals insulator GeP under pressure. This is shown to result from valence skipping of the Ge cation, altering its average valency from 3+ to 4+, turning GeP from a layered compound to a three-dimensional covalent system with superconducting critical temperature reaching its maximum of 10 K. Such a valence-skipping-induced superconductivity with a quasi-two-dimensional nature in thin samples, showing a Berezinskii-Kosterlitz-Thouless-like character, is further confirmed by angle-dependent upper-critical-field measurements. These findings provide a model system to examine competing order parameters in valence-skipping systems.

ObjectiveTo determine the distribution and diagnostic value of peripheral enthesitis detected by whole-body MRI (WBMRI) in axial spondyloarthritis (axSpA) diagnosis, and to determine the value of the peripheral enthesitis score in axSpA assessment.MethodsSixty axSpA patients [mean age of 33.2 (24.8–40.6) years] and 50 controls with chronic low back pain (LBP) [mean age of 34.7 (28.3–41.1) years] were enrolled. The gold standard was physician’s comprehensive diagnosis based on current classification criteria and physical examination. All subjects underwent WBMRI, and 47 peripheral entheses were assessed for each patient with scores of 0–188.ResultsWBMRI identified 155 enthesitis sites in 78.3% (n = 47) patients with axSpA. Meanwhile, 23 enthesitis sites were identified in 32% (n = 16) controls. The pelvis had the maximum number of enthesitis sites (52, 33.5%) in axSpA patients. Pelvic and anterior chest wall enthesitis had the highest sensitivity (51.67%) and specificity (100%) in axSpA diagnosis, respectively. There were different manifestations of enthesitis subtypes between axSpA patients and the control group. Osteitis was more present than soft-tissue inflammation in axSpA patients. The AUC for the number of enthesitis sites was 0.819 (95% CI 0.739–0.899), and that for the enthesitis score was 0.833 (95% CI 0.755–0.910), indicating statistically significant differences (P = 0.025). Based on the Youden index and clinical need, three enthesitis sites (sensitivity of 53.33, specificity of 98, and Youden index of 0.51) and enthesitis score (sensitivity of 58.33, specificity of 98, and Youden index of 0.56) may have the greatest value for axSpA diagnosis.ConclusionThe distribution of peripheral enthesitis can be adequately assessed by whole-body MRI, which could help diagnose axial spondyloarthritis. The enthesitis score may provide a more accurate assessment and diagnostic tool in axSpA compared with enthesitis site counting.

Nanozymes, as a unique class of nanomaterials with enzyme-like properties, have attracted significant interest due to their potential applications in many significant fields. Great endeavours have been made to improve the catalytic activities of nanozymes; however, it is still a challenging issue to develop nanozymes that can functionally mimic multiplex enzymes with broader application prospects. Here, we develop a simple hydrothermal method to construct "three-in-one" nanocomposites as multifunctional nanozymes for the ultrasensitive ratiometric fluorescence detection of alkaline phosphatase (ALP). The prepared flower-like Fe

With the growing demand for the development of intranasal (IN) products, such as nasal vaccines, which has been especially highlighted during the COVID-19 pandemic, the lack of novel technologies to accurately test the safety and effectiveness of IN products in vitro so that they can be delivered promptly to the market is critically acknowledged. There have been attempts to manufacture anatomically relevant 3D replicas of the human nasal cavity for in vitro IN drug tests, and a couple of organ-on-chip (OoC) models, which mimic some key features of the nasal mucosa, have been proposed. However, these models are still in their infancy, and have not completely recapitulated the critical characteristics of the human nasal mucosa, including its biological interactions with other organs, to provide a reliable platform for preclinical IN drug tests. While the promising potential of OoCs for drug testing and development is being extensively investigated in recent research, the applicability of this technology for IN drug tests has barely been explored. This review aims to highlight the importance of using OoC models for in vitro IN drug tests and their potential applications in IN drug development by covering the background information on the wide usage of IN drugs and their common side effects where some classical examples of each area are pointed out. Specifically, this review focuses on the major challenges of developing advanced OoC technology and discusses the need to mimic the physiological and anatomical features of the nasal cavity and nasal mucosa, the performance of relevant drug safety assays, as well as the fabrication and operational aspects, with the ultimate goal to highlight the much-needed consensus, to converge the effort of the research community in this area of work.

BACKGROUND: Multiple myeloma (MM) is a blood cancer caused by the unlimited proliferation of intramedullary plasma cells. The presence of focal lesions (FLs) is presumed to be a more relevant factor for patient outcomes and risk distribution than diffuse bone marrow signal abnormalities. Signal changes in these FLs also have a good correlation with prognosis. As the cell density increased, a lower apparent diffusion coefficient (ADC) value was found with the diffusion-weighted imaging (DWI) sequence. Therefore, whole-body magnetic resonance imaging (MRI) with DWI sequences is sensitive to cell density and viability and may be vital for disease detection and therapy response assessments. However, the correlation between the DWI signal and the degree of bone destruction and the proportion of bone marrow plasma cells (BMPC) was still unclear in patients with MM. Water-fat separation MRI is used mainly for evaluating liver and bone marrow fat quantification, and fat quantification in other diseases. Meanwhile, it is also possible to assess the extent of bone marrow invasion in medullary lesions. This study aimed to investigate the correlation between ADC values from whole-body DWI and water/fat MRI signals from T1-weighted water-fat separation in evaluating bone marrow infiltration in patients with MM. METHODS: The study included 35 patients with MM who underwent whole-body DWI and T1-weighted water-fat separation Dixon examinations before therapy. The ADC values, normalized fat signal intensity (nMfat), normalized water molecular signal intensity (nMwater), and normalized fat fraction (nFF) of the thoracolumbar spine was measured in FLs and the normal-appearing bone marrow (NABM). The differences in values were compared using the independent-samples t-test. The correlation between ADC values and water-fat MRI signals was estimated using the Pearson or Spearman correlation test. The correlation between the MRI above parameters and proportions of BMPC was also explored. RESULTS: Statistically significant differences were found between the mean ADC values in FLs and NABM (0.72 vs. 0.33 mm(2)/s, P0.05). The ADC value highly correlated with nMfat and nFF values and moderately with the nMwater value in FLs (r=–0.899, –0.834, 0.642, respectively, P

Artificial Intelligence (AI) promises solutions to the challenges raised by the digitalization of power grids and their assets. Decision-making, forecasting and even operational optimization of grids and assets are just some of the solutions that AI algorithms can provide to operators, utilities and vendors. Nevertheless, barriers such as access to quality datasets, interpretability, repeatability, and availability of computational resources currently limit the extent of practical AI implementations. At the same time, Digital Twins (DTs) are foreseen as platforms that can overcome these barriers, and also provide a new environment for the development of enhanced and more intelligent applications. In this manuscript, we review the published literature to determine the existing capabilities and implementation challenges of AI algorithms in power systems, and classify AI-based applications based on their time scale to reveal their temporal sensitivity. Furthermore, DT-based technologies are discussed, identifying the potentials to tackle current limitations of real-world AI applications as well as exploring the synergies between DTs and AI. By combining AI and DT, we outline multiple prospective use cases for AI-enhanced power grid and power asset DTs. Our review also identifies that the combination of AI-based solutions and DTs leverages new applications with the potential to fundamentally change multiple aspects of the power industry.

In this paper, we explore the potential of using the multivoxel proton magnetic resonance spectroscopy (1H-MRS) to diagnose neuropsychiatric systemic lupus erythematosus (NPSLE) with the assistance of a support vector machine broad learning system (BL-SVM). We retrospectively analysed 23 confirmed patients and 16 healthy controls, who underwent a 3.0 T magnetic resonance imaging (MRI) sequence with multivoxel 1H-MRS in our hospitals. One hundred and seventeen metabolic features were extracted from the multivoxel 1H-MRS image. Thirty-three metabolic features selected by the Mann-Whitney U test were considered to have a statistically significant difference ( p < 0.05 ). However, the best accuracy achieved by conventional statistical methods using these 33 metabolic features was only 77%. We turned to develop a support vector machine broad learning system (BL-SVM) to quantitatively analyse the metabolic features from 1H-MRS. Although not all the individual features manifested statistics significantly, the BL-SVM could still learn to distinguish the NPSLE from the healthy controls. The area under the receiver operating characteristic curve (AUC), the sensitivity, and the specificity of our BL-SVM in predicting NPSLE were 95%, 95.8%, and 93%, respectively, by 3-fold cross-validation. We consequently conclude that the proposed system effectively and efficiently working on limited and noisy samples may brighten a noinvasive in vivo instrument for early diagnosis of NPSLE.

ObjectivesTo evaluate the diagnostic and prognostic values of glutamate chemical exchange saturation transfer (GluCEST) magnetic resonance imaging as a quantitative method for pathogenetic research and clinical application of carbon monoxide (CO) poisoning-induced encephalopathy combined with the proton magnetic resonance spectroscopy (1H-MRS) and the related histopathological and behavioral changes.MethodsA total of 63 Sprague–Dawley rats were randomly divided into four groups. Group A (n = 12) was used for animal modeling verification; Group B (n = 15) was used for magnetic resonance molecular imaging, Group C (n = 15) was used for animal behavior experiments, and Group D (n = 21) was used for histopathological examination. All the above quantitative results were analyzed by statistics.ResultsThe peak value of carboxyhemoglobin saturation in the blood after modeling was 7.3-fold higher than before and lasted at least 2.5 h. The GluCEST values of the parietal lobe, hippocampus, and thalamus were significantly higher than the base values in CO poisoning rats (p < 0.05) and the 1H-MRS showed significant differences in the parietal lobe and hippocampus. In the Morris water maze tests, the average latency and distance were significantly prolonged in poisoned rats (p < 0.05), and the cumulative time was shorter and negatively correlated with GluCEST.ConclusionThe GluCEST imaging non-invasively reflects the changes of glutamate in the brain in vivo with higher sensitivity and spatial resolution than 1H-MRS. Our study implies that GluCEST imaging may be used as a new imaging method for providing a pathogenetic and prognostic assessment of CO-associated encephalopathy.

Most existing key generation schemes cannot achieve the optimal performance because the quantization algorithm cannot make full use of channel information, some schemes use amplitude quantization and others use phase quantization. This paper proposes the concept of vector partitioning quantization (VPQ), and several new quantization algorithms are obtained further, which can utilize amplitude and phase at the same time. First, the traditional amplitude quantization (TAQ) and the traditional phase quantization (TPQ) are reviewed in detail. Second, the regular vector partitioning quantization (RVPQ) is proposed based on TAQ and TPQ, and the error probabilities of RVPQ is deduced, moreover, the concept of optimal RVPQ is presented. Then, three irregular vector partitioning quantization (IVPQ) algorithms are proposed which utilizes K-means clustering, including basic K-means quantization (BKQ), lossy K-means quantization (LKQ) and compensation K-means quantization (CKQ). The three K-means quantization algorithms can not only reduce the quantization error rate greatly, but also ensure the confidentiality of key generation. To overcome the problem of weak uniformity caused by K-means, we put forward the balance mechanism (BM) and apply it to three K-means quantization algorithms. Finally, the simulation results show the VPQ algorithms proposed are superior to previous methods.

As a variant modular converter configuration, the alternate arm converter (AAC) is well-suited for high-voltage power transmission and large-scale integration of renewables. In contrast to conventional multilevel converters, the director switches in the arms of AAC lead to the introduction of an overlap period, during which circuiting current can flow through the two arms in the same phase. Thus, fixed or variable overlap period control can be implemented in AAC systems so as to dynamically balance stored arm energy. However, the control of overlap period is linked to instability issues that might impede the safe operation of AAC systems, which are yet to be reported. In this paper, the stability of an AAC system is demonstrated based on measured grid and converter impedance, in conjunction with impedance-based stability criterion in the dq frame. The interaction between harmonic sources at AC and DC sides of the AAC system is analyzed to determine resonant frequencies in the AC current when any potential resonance is identified in the dq frame. Novel results with respect to the impact of overlap period on the system stability are obtained by depicting and comparing the Eigenloci in the polar plot, which are validated by real-time simulations.

Background Nanomedicine is a promising new approach to cancer treatment that avoids the disadvantages of traditional chemotherapy and improves therapeutic indices. However, the lack of a real-time visualization imaging technology to monitor drug distribution greatly limits its clinical application. Image-tracked drug delivery is of great clinical interest; it is useful for identifying those patients for whom the therapy is more likely to be beneficial. This paper discusses a novel nanomedicine that displays features of nanoparticles and facilitates functional magnetic resonance imaging but is challenging to prepare. Results To achieve this goal, we synthesized an acylamino-containing amphiphilic block copolymer (polyethylene glycol-polyacrylamide-polyacetonitrile, PEG-b-P(AM-co-AN)) by reversible addition-fragmentation chain transfer (RAFT) polymerization. The PEG-b-P(AM-co-AN) has chemical exchange saturation transfer (CEST) effects, which enable the use of CEST imaging for monitoring nanocarrier accumulation and providing molecular information of pathological tissues. Based on PEG-b-P(AM-co-AN), a new nanomedicine PEG-PAM-PAN@DOX was constructed by nano-precipitation. The self-assembling nature of PEG-PAM-PAN@DOX made the synthesis effective, straightforward, and biocompatible. In vitro studies demonstrate decreased cytotoxicity of PEG-PAM-PAN@DOX compared to free doxorubicin (half-maximal inhibitory concentration (IC50), mean ~ 0.62 μg/mL vs. ~ 5 μg/mL), and the nanomedicine more efficiently entered the cytoplasm and nucleus of cancer cells to kill them. Further, in vivo animal experiments showed that the nanomedicine developed was not only effective against breast cancer, but also displayed an excellent sensitive CEST effect for monitoring drug accumulation (at about 0.5 ppm) in tumor areas. The CEST signal of post-injection 2 h was significantly higher than that of pre-injection (2.17 ± 0.88% vs. 0. 09 ± 0.75%, p Conclusions The nanomedicine with CEST imaging reflects the characterization of tumors and therapeutic functions has great potential medical applications.

The unique electronic structure and crystal structure driven by external pressure in transition metal tellurides (TMTs) can host unconventional quantum states. Here, the discovery of pressure‐induced phase transition at ≈2 GPa, and dome‐shaped superconducting phase emerged in van der Waals layered NbIrTe4 is reported. The highest critical temperature (T c) is ≈5.8 K at pressure of ≈16 GPa, where the interlayered Te–Te covalent bonds form simultaneously derived from the synchrotron diffraction data, indicating the hosting structure of superconducting evolved from low‐pressure two‐dimensional (2D) phase to three‐dimensional (3D) structure with pressure higher than 30 GPa. Strikingly, the authors have found an anisotropic transport in the vicinity of the superconducting state, suggesting the emergence of a “stripe”‐like phase. The dome‐shaped superconducting phase and anisotropic transport are possibly due to the spatial modulation of interlayer Josephson coupling ., The correlation of novel electrical properties and structural evolutions in van der Waals layered material is revealed by performing special high‐pressure measurements. A superconducting model is proposed to explain the emergence of “stripe”‐like phases and the evolution of critical temperature. Spatial modulation of interlayer Josephson coupling furthers the understanding of the complex relationships between structure, anisotropy, and superconductivity.

To balance the phase output currents of a multiphase inverter in a wireless power transfer (WPT) system, negatively coupled inductors can be utilized to achieve a larger differential mode (DM) loop impedance than the common mode loop impedance. For a good current balancing effect, the inductances of the negatively coupled inductors should be large, leading to extra losses, cost ineffectiveness, and bulky size, which should be avoided in high-power applications. To solve these issues, this paper proposes a novel current balancing method based on parallel resonance. For a series-series compensated WPT system, part of the compensating capacitance is employed to form a parallel resonant network together with an extra inductor. The DM currents are suppressed by the large impedance of the parallel resonant network. Compared with the existing method, the inductances of the negatively coupled inductors can be greatly reduced to achieve far better current balancing performance, at the cost of adding an inductor with a small current rating, which is only visible for the DM currents. A prototype is implemented to validate the proposed method.

In light of the global effort to limit the temperature rise, many cities have undertaken initiatives to become climate-neutral, making decentralized urban energy production more relevant. This paper addresses the potential of urban wind energy production with small wind turbines, using Berlin as an example. A complete framework from data selection to economic feasibility is constructed to enable the empirical assessment of wind energy for individual buildings and Berlin as a whole. Based on a detailed dataset of all buildings and hourly wind speed on a 1 km2 grid, the results show that multiple turbines on suitable buildings can significantly contribute to households’ energy consumption but fall short of covering the full demand. For individual households, our economic evaluation strongly recommends the self-consumption of the produced electricity. The findings suggest that while the use of small wind turbines should be continuously encouraged, exploring other renewable resources or combination of wind and photovoltaic energy in the urban environment remains important.

Laminated ceramics with weak interface layers have been proven to be effective in toughening ceramics. The energy absorption ability of laminated ceramics may also benefit their ballistic performance. However, the effect of the layer structure on the ballistic performance of laminated ceramics has not been studied. Focusing on the application for body armor, this paper studied the effect of the different layer structures on the ballistic performance of laminated SiC ceramics. The laminated SiC ceramics with different layered structures were designed and prepared by tape-casting and hot-pressing. When used for the ‘in conjunction with’ armor system, the laminated SiC ceramics with a gradual-layered structure had the backface signature depth of 30% less than the laminated SiC with no interface structure and 50% less than the commercial solid-state sintered SiC. However, when used stand-alone, the laminated SiC had a similar ballistic performance regardless of the layer structure, which was likely due to the weak back support. In conclusion, the ballistic performance of the laminated ceramics was related to the back support of the armor system. When used for the ‘in conjunction with’ armor system, the laminated SiC had a better ballistic performance than that of the solid-state sintered SiC.

BACKGROUND: Preoperative microvascular invasion (MVI) prediction plays an important role in therapeutic decision-making of hepatocellular carcinoma (HCC). This study aimed to investigate the value of histogram based on the arterial phase (AP) of magnetic resonance imaging (MRI) with extracellular contrast agent compared with radiological features for predicting MVI of solitary HCC. METHODS: In total, 113 patients with pathologically proven solitary HCC were retrospectively enrolled who received surgical resection and underwent preoperative abdominal MRI. The patients were divided into the ≤3 cm [small HCC (sHCC)] cohort and the >3 cm cohort. Based on pathological analysis of surgical specimens, the patients were classified into MVI negative (MVI−) and MVI positive (MVI+) groups. Peritumoral and intratumoral histogram features [mean, median, standard deviation (Std), coefficient of variation (CV), skewness, kurtosis] were acquired on AP subtraction images and radiological features [size, capsule, corona enhancement, corona enhancement thickness (CET), CET group]. Receiver operating characteristic (ROC) curve was constructed to assess predictive capability. Subgroup analysis of patients with a visible corona enhancement based on the CET cut-off value was performed. RESULTS: None of the features extracted from the intratumor area were significantly different between the MVI+ and MVI− groups in both cohorts. Histogram defined peritumoral (peri-) mean, median, kurtosis, and radiological features including CET and CET group were associated with MVI in sHCCs. Peri-mean, median, Std and radiological features including incomplete capsule, CET, and CET group were associated with MVI in HCC >3 cm. In multivariate logistic regression analysis, the CET group and peri-mean were independent predictors for HCC >3 cm with an area under the curve (AUC) of 0.741. Peri-mean was an independent predictor for sHCC (AUC =0.798). Subgroup analysis of the corona enhancement using 8 mm as a cut-off value showed 100% sensitivity and negative predictive value (NPV). CONCLUSIONS: Peritumoral AP enhanced degree on MRI showed an encouraging predictive performance for preoperative prediction of MVI, especially in sHCCs. CET ≤8 mm could be used as a negative predictive marker for MVI.

One of the changes introduced by the U.S. 2018 Farm Bill in the Agricultural Risk Coverage-County (ARC-CO) programme is the requirement to use Risk Management Agency (RMA) programme-based data rather than National Agricultural Statistics Service (NASS) survey-based data. This study compares the NASS and RMA county yield data for the period 1991–2015 and finds no systematic differences between the two data sets. Additionally, using RMA or NASS yield data results in relatively small and statistically insignificant differences in the ARC-CO payments. The spatial disparities across neighbouring counties in ARC-CO payments are also similar, no matter whether NASS or RMA data are used.

The biological response of bronchial epithelial cells to particles is associated with a sequestration of cell metal by the particle surface and a subsequent disruption in host iron homeostasis. The macrophage is the cell type resident in the respiratory tract that is most likely to make initial contact with inhaled particles. We tested the postulates that (1) silica, a prototypical particle, disrupts iron homeostasis in alveolar macrophages (AMs); and (2) the altered iron homeostasis results in both an oxidative stress and pro-inflammatory effects. Human AMs (1.0 × 106/mL) demonstrated an increased import of iron following particle exposure with nonheme iron concentrations of 0.57 ± 0.03, 1.72 ± 0.09, 0.88 ± 0.09, and 3.21 ± 0.11 ppm in cells exposed for 4 h to media, 500 μM ferric ammonium citrate (FAC), 100 μg/mL silica, and both silica and FAC, respectively. Intracellular ferritin concentrations and iron release were similarly increased after AM exposure to FAC and silica. Silica increased oxidant generation by AMs measured using both dichlorofluorescein diacetate fluorescence and reduction of nitroblue tetrazolium salt. Concentrations of interleukin (IL)-1β, IL-6, IL-8, and tumor necrosis factor-α in macrophage supernatant increased following 100 μg/mL silica exposure for 24 h. Treatment of AMs with 500 μM FAC decreased both oxidant generation and cytokine release associated with silica exposure, supporting a dependence of these effects on sequestration of cell metal by the particle surface. We conclude that (1) silica exposure disrupts iron homeostasis resulting in increased import, accumulation, and release of the metal; and (2) the altered iron homeostasis following silica exposure impacts oxidant generation and pro-inflammatory effects.