A 1270 Hz resonance occurred between ±350 kV/ 1000 MW Luxi back-to-back voltage source converter based high-voltage dc transmission (VSC-HVDC) converter and the 525 kV ac grid after disconnection of ...several ac transmission lines. To understand the resonance and find a solution, the impedance-based stability analysis model considering different equipment is first established. Then, the resonance is analyzed and repeated in the simulation based on the established model. The system stability can be judged by the ratio of grid impedance to the equivalent impedance of all parallel-connected equipment with the converter. To evaluate the occurrence and risk of resonance, the frequency range where the impedance has a negative-real-part has been searched and studied. In order to narrow the negative-real-part region to avoid potential resonance, solutions such as control strategy improvement and passive or active impedance adapter may be applicable and are discussed. For a complex system containing various equipment, the equipment can be divided into several subsectors to avoid modeling all possible combinations of equipment, which can be exhausting. And analysis has shown sufficient but not necessary condition to stabilize the system is to avoid the negative-real-part region in each sector.
We report a camptothecin (CPT) prodrug that was well formulated in solution and rapidly transformed into long-circulating nanocomplexes in vivo for highly efficient drug delivery and effective cancer ...therapy. Specifically, using a redox-responsive disulfide linker, CPT was conjugated with an albumin-binding Evans blue (EB) derivative; the resulting amphiphilic CPT-ss-EB prodrug self-assembled into nanostructures in aqueous solution, thus conferring high solubility and stability. By binding CPT-ss-EB to endogenous albumin, the 80 nm CPT-ss-EB nanoparticles rapidly transformed into 7 nm albumin/prodrug nanocomplexes. CPT-ss-EB was efficient at intracellular delivery into cancer cells, released intact CPT in a redox-responsive manner, and exhibited cytotoxicity as potent as CPT. In mice, the albumin/CPT-ss-EB nanocomplex exhibited remarkably long blood circulation (130-fold greater than CPT) and efficient tumor accumulation (30-fold of CPT), which consequently contributed to excellent therapeutic efficacy. Overall, this strategy of transformative nanomedicine is promising for efficient drug delivery.
Calcium (Ca), potassium (K) and magnesium (Mg) may be involved in the occurrence and development of glaucoma by influencing the retinal oxidative stress and regulate blood pressure. However, ...epidemiological opinions on dietary intake of macroelement related to glaucoma are inconsistent. Herein, this study aims to explore the association between dietary Ca, K, and Mg consumption and glaucoma. Data of 7,042 adults aged greater than or equal to40 years old who received the glaucoma examinations were extracted from the National Health and Nutrition Examination Survey (NHANES) database from 2005 to 2008 in this cross-sectional study. Univariate and multivariate logistic regression were used to explore the association between dietary Ca, K, and Mg intake and glaucoma with the odd ratios (ORs) and 95% confidence intervals (CIs). We also investigated this relationship in individuals of different age, with/without hypertension and visual field defect (VFD). There were 502 (8.11%) participants had glaucoma. After adjusted for covariables, we found that enough dietary Ca consumption was related to a decreased risk of glaucoma OR = 0.59, 95%CI: (0.42-0.81), whether in persons with/without hypertension (all P<0.05). In particular, dietary K intake may be a potential protect factor for glaucoma in non-hypertension populations OR = 0.47, 95%CI: (0.22-0.99), P = 0.049. Additionally, hypertension/non-hypertension persons who aged <65 years old or with/without VFD should all pay attention to the enough dietary supplement of Ca, K, and Mg according to their own circumstances. Enough dietary Ca, K, and Mg consumption may be potential protect factors of glaucoma that could provide some dietary reference for developing targeted glaucoma prevention and control measures.
With the development of hyperspectral sensing technology, hyperspectral target detection technology plays an important role in remote target detection. However, existing hyperspectral target ...detection models are poorly adapted to complex backgrounds and mainly focus on the spectral domain, making less use of spatial structure information leading to low target detection rates. Therefore, a new target detection algorithm based on the prior spectral perception and local graph fusion is proposed. First, the prior spectrum-guided target extraction method is established. This method can take full advantage of the background and target spectral information by local inner and outer window linkage, reduce the impact of spectral variability on target acquisition performance, and improve detection stability. Second, the target enhancement strategy based on the Gabor multifeature graph is proposed. This technique makes full use of multidirectional and multiscale spatial information, which can reduce the influence of brightness, contrast and amplitude variation on detection performance due to light and angle. Finally, spatial-spectral fusion is executed to achieve target detection. It can make full use of spectral and spatial structure information to improve the target detection effect. Publicly available datasets and real collected datasets are adopted to check the validity of the proposed method. After comparison, it is found that the proposed algorithm has better detection effect than existing baseline methods. The maximum improvement in AUC values are 16.56%-88.16% across the eight datasets.
Immunotherapy is revolutionizing the clinical management of patients with different cancer types by sensitizing autologous or allogenic immune cells to the tumor microenvironment which eventually ...leads to tumor cell lysis without rapidly killing normal cells. Although immunotherapy has been widely demonstrated to be superior to chemotherapies, only a few populations of patients with specific cancer types respond to such treatment due to the failure of systemic immune activation. In addition, severe immune-related adverse events are rapidly observed when patients with very few responses are given higher doses of such therapies. Recent advances of lipid-based nanoparticles (NPs) development have made it possible to deliver not only small molecules but also mRNAs to achieve systemic anticancer immunity through cytotoxic immune cell activation, checkpoint blockade, and chimeric antigen receptor cell therapies, etc. This review summarized recent development and applications of LNPs in anticancer immunotherapy. The diversity of lipid-based NPs would encapsulate payloads with different structures and molecular weights to achieve optimal antitumor immunity through multiple mechanisms of action. The discussion about the components of lipid-based NPs and their immunologic payloads in this review hopefully shed more light on the future direction of anticancer immunotherapy.
The aim of the present study is to design and characterize quercetin-loaded solid lipid nanoparticles (QT-SLNs), clarify the absorption mechanism of QT-SLNs and to evaluate the potential of using ...solid lipid nanoparticles (SLNs) as an oral delivery carrier for poorly water soluble drugs. QT-SLNs were prepared by an emulsification and low-temperature solidification method. The QT-SLNs presented as spherically shaped under transmission electron microscopy, with an average diameter of 155.3 nm. The average drug entrapment efficiency, drug loading and zeta potential were 91.1%, 13.2% and −
32.2 mV, respectively. Drug release from QT-SLNs was fitted to a double phase kinetics model and the equation was as follows: 100
−
Q
=
98.87e
−
0.1042t
+
42.45e
−
0.0258t
. The absorption of QT-SLNs in the gastrointestinal (GI) tract was studied using an
in situ perfusion method in rats. It was found that the absorption percent in the stomach for 2 h was only 6.20%
, the absorption process of intestine was first-process with passive diffusion mechanism, and the main absorptive segments were ileum and colon. A pharmacokinetic study was conducted in rats after oral administration of quercetin at 50 mg/kg in the form of either QT-SLNs or suspension. The plasma concentration-time curves were both fitted to a one-compartment model. The relative bioavailability of QT-SLNs to quercetin suspension was 571.4%. The T
max and MRT for quercetin in plasma were both delayed. Our studies provide evidence that SLNs are valuable as an oral delivery carrier to enhance the absorption of a poorly water soluble drug, quercetin.
•A transform domain-based revised constrained energy minimization detector is proposed.•The fractional Fourier transform is adopted to improve the separability of background and ...target.•Multi-direction double window summation strategy is used to make full of the local spatial statistical information.•Pearson correlation coefficient is weighted to further adaptively adjust detection accuracy.
Traditional hyperspectral target detection methods use spectral domain information for target recognition. Although it can effectively retain intrinsic characteristics of substances, targets in homogeneous regions still cannot be effectively recognized. By projecting the spectral domain features on the transform domain to increase the separability of background and target, fractional domain-based revised constrained energy minimization detector is proposed. Firstly, the fractional Fourier transform is adopted to project the original spectral information into the fractional domain for improving the separability of background and target. Then, a newly revised constrained energy minimization detector is performed, where sliding double window strategy is used to make the best of the local spatial statistical characteristics of testing pixel. In order to make the best of inner window information, the mean value of Pearson correlation coefficient is measured between prior target pixel and testing pixel associated with its four neighborhood pixels. Extensive experiments for four real hyperspectral scenes indicate that the performance of the proposed algorithm is excellent when compared with other related detectors.
Abstract
Objective
The purpose of this study was to compare the therapeutic effects of Kirschner wire fixation and external fixation in the treatment of proximal humeral fractures in older children ...and adolescents.
Methods
A retrospective analysis was performed on the clinical data of older children and adolescents who underwent surgery at our institution for proximal humeral fractures between April 2014 and May 2022. One group (n = 28) underwent fracture reduction and Kirschner wire fixation, and the other group (n = 23) underwent external fixation. During the follow-up, the differences in shoulder joint function between the two groups were compared by analysing Quick Disabilities of the Arm, Shoulder, and Hand (Quick DASH) and Constant-Murley scores. Postoperative complications were also recorded.
Results
The operation time of the Kirschner wire group was shorter than that of the external fixation group (69.07 ± 11.34 min vs. 77.39 ± 15.74 min,
P
= 0.33). The time to remove the fixator in the external fixation group was shorter than that in the Kirschner wire group (6.74 ± 1.57 vs. 7.61 ± 1.22,
P
= 0.032). The Quick DASH score and Constant-Murley score of the patients in the external fixation group were significantly better than those in the Kirschner wire group at 3 months after surgery (5.63 ± 4.33 vs. 8.93 ± 6.40,
P
= 0.040; 93.78 ± 2.43 vs. 91.75 ± 2.15,
P
= 0.003). There was no significant difference in the Quick DASH score or Constant-Murley score between the patients in the external fixator group and those in the Kirschner wire group at 9 months after the operation (2.77 ± 3.14 vs. 3.17 ± 3.68,
P
= 0.683; 97.39 ± 1.80 vs. 96.57 ± 2.15,
P
= 0.152). The most common complication of the two groups was pin tract infection. The incidence rate of infection was higher in the external fixation group than that in the Kirschner wire group (9 vs. 4,
P
= 0.043).
Conclusion
Both Kirschner wire fixation and external fixation of N-H III and IV proximal humeral fractures in older children and adolescents produce good outcomes. External fixation is a preferred surgical treatment option for paediatric proximal humerus fractures because early mobilization of the affected limb can be realized.
In recent years, with the development of compressed sensing theory, sparse representation methods have been concerned by many researchers. Sparse representation can approximate the original image ...information with less space storage. Sparse representation has been investigated for hyperspectral imagery (HSI) detection, where approximation of testing pixel can be obtained by solving l1-norm minimization. However, l1-norm minimization does not always yield a sufficiently sparse solution when a dictionary is not large enough or atoms present a certain level of coherence. Comparatively, non-convex minimization problems, such as the lp penalties, need much weaker incoherence constraint conditions and may achieve more accurate approximation. Hence, we propose a novel detection algorithm utilizing sparse representation with lp-norm and propose adaptive iterated shrinkage thresholding method (AISTM) for lp-norm non-convex sparse coding. Target detection is implemented by representation of the all pixels employing homogeneous target dictionary (HTD), and the output is generated according to the representation residual. Experimental results for four real hyperspectral datasets show that the detection performance of the proposed method is improved by about 10% to 30% than methods mentioned in the paper, such as matched filter (MF), sparse and low-rank matrix decomposition (SLMD), adaptive cosine estimation (ACE), constrained energy minimization (CEM), one-class support vector machine (OC-SVM), the original sparse representation detector with l1-norm, and combined sparse and collaborative representation (CSCR).
Kompetitive allele-specific PCR (KASP) is a cost-effective single-step SNP genotyping technology, With an objective to enhance the marker repertoire and develop high efficient KASP-SNP markers in ...Chinese cabbage, we re-sequenced four Chinese cabbage doubled haploid (DH) lines, Y177-47, Y635-10, Y510-1 and Y510-9, and generated a total of more than 38.5 billion clean base pairs. A total of 827,720 SNP loci were identified with an estimated density of 3,217 SNPs/Mb. Further, a total of 387,354 SNPs with at least 30 bp to the next most adjacent SNPs on either side were selected as resource for KASP markers. From this resource, 258 (96.27%) of 268 SNP loci were successfully transformed into KASP-SNP markers using a Roche LightCycler 480-II instrument. Among these markers, 221 (85.66%) were co-dominant markers, 220 (85.27%) were non-synonymous SNPs, and 257 (99.6%) were newly developed markers. In addition, 53 markers were applied for genotyping of 34 Brassica rapa accessions. Cluster analysis separated these 34 accessions into three clusters based on heading types. The millions of SNP loci, a large set of resource for KASP markers, as well as the newly developed KASP markers in this study may facilitate further genetic and molecular breeding studies in Brassica rapa.
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