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• We sincerely thank the experts for reviewing our article during their busy schedules. The main contents of our article are as follows: • How to ensure that the aerial photos used for positioning have high accuracy is a pressing concern. The conventional approach relies on the number of matching feature points between aerial and satellite photos and verifying whether the aerial photo center projection falls within a designated area of the satellite photo. However, this method often yields subpar accuracy. • To address this issue and select aerial photos for high-precision localization, we propose an image moment extraction (abbreviated as IME) module, which serves as the main innovation of this paper. The IME module contains two parts: the relative error of the image invariant moment and the area relative error. The former is used to select the aerial photos with good performance in translation, rotation and scaling before and after projection, and the latter is adopted to reject aerial photos with excessive scaling before and after projection. Through experiments, we demonstrate the effectiveness and superiority of this approach. Results show that the image moment extraction module, when used for positioning with aerial photo center projection, significantly reduces the mean absolute error in UAV geolocation from 63.220 m to 9.454 m. The maximum error is reduced from 486.7 m to 47.194 m, with 70.96% of aerial photos suitable for positioning. This research is pivotal for achieving high-precision UAV geolocation in GPS-free environments. Since GPS is susceptible to environmental interference or cannot be used in some specific situations, it is important to study the UAV geolocation under GPS-free condition. How to ensure that the aerial photos used for positioning have high accuracy is a pressing concern. The conventional approach relies on the number of matching feature points between aerial and satellite photos and verifying whether the aerial photo center projection falls within a designated area of the satellite photo. However, this method often yields suboptimal accuracy. This paper introduces a novel method for selecting aerial photos for geolocation based on an image moment extraction module. The image moment extraction module contains two parts: the relative error of the image invariant moment and the area relative error. The former is used to select the aerial photos with good performance in translation, rotation and scaling before and after projection, and the latter is adopted to reject aerial photos with excessive scaling before and after projection. Through experiments, we demonstrate the effectiveness and superiority of this approach. Results show that the image moment extraction module, when used for positioning with aerial photo center projection, significantly reduces the mean absolute error in UAV geolocation from 63.220 m to 9.454 m. The maximum error is reduced from 486.7 m to 47.194 m, with 70.96% of aerial photos suitable for positioning. This research is pivotal for achieving high-precision UAV geolocation in GPS-free environments. [ABSTRACT FROM AUTHOR]

Abstract: A kind of amphiphilic biodegradable oligosaccharide-based graft copolymer was prepared and characterized by IR, H NMR and GPC, in which each hydrophobic poly(ɛ-caprolactone) (PCL, average length ) was controlled grafted onto the 3-position hydroxyl group of the short and water soluble maltoheptaose (MH, DP=7) backbone. The self-assembled structures in water of the amphiphilic MH-g-PCL6 copolymer with a short main chain and controlled branched structure were investigated by transmission electron microscopy (TEM) and dynamic light scattering (DLC). The graft copolymer with a unique asymmetric structure self-assembled into wire-like micelles with average diameters of 76nm. And the length of the nano-wire increased with increased initial copolymer concentration in dimethylformamide. Thus, a new route to form self-assembled nano-wires with different lengths and interesting biodegradable properties was developed using amphiphilic oligosaccharide-based graft copolymer in water. The possible formation mechanism of nano-wire micelles was also discussed. [Copyright &y& Elsevier]

Abstract: Aim: Upregulation of microRNA 16 (miR-16) contributed to the differentiation of human bone marrow mesenchymal stem cells (hMSCs) toward myogenic phenotypes in a cardiac niche, the present study aimed to determine the role of miR-16 in this process. Main methods: hMSCs and neonatal rat ventricular myocytes were co-cultured indirectly in two chambers to set up a cardiac microenvironment (niche). miRNA expression profile in cardiac-niche‐induced hMSCs was detected by miRNA microarray. Cardiac marker expression and cell cycle analysis were determined in different treatment hMSCs. Quantitative real-time PCR and Western blot were used to identify the expression of mRNA, mature miRNA and protein of interest. Key findings: miRNA dysregulation was shown in hMSCs after cardiac niche induction. miR-16 was upregulated in cardiac-niche‐induced hMSCs. Overexpression of miR-16 significantly increased G1-phase arrest of the cell cycle in hMSCs and enhanced the expression of cardiac marker genes, including GATA4, NK2-5, MEF2C and TNNI3. Differentiation-inducing factor 3 (DIF-3), a G0/G1 cell cycle arrest compound, was used to induce G1 phase arrest in cardiac-niche‐induced hMSCs, and the expression of cardiac marker genes was up-regulated in DIF-3-treated hMSCs. The expression of CCND1, CCND2 and CDK6 was suppressed by miR-16 in hMSCs. CDK6, CCND1 or CCND2 knockdown resulted in G1 phase arrest in hMSCs and upregulation of cardiac marker gene expression in hMSCs in a cardiac niche. Significance: miR-16 enhances G1 phase arrest in hMSCs, contributing to the differentiation of hMSCs toward myogenic phenotypes when in a cardiac niche. This mechanism provides a novel strategy for pre-modification of hMSCs before hMSC-based transplantation therapy for severe heart diseases. [Copyright &y& Elsevier]

Thromboxane A 2 (TXA 2 ) has been implicated in the pathogenesis of diabetic vascular complications, although the underlying mechanism remains unclear. The present study investigated the alterations in TXA 2 receptor signal transduction in type 2 diabetic renal arteries. The contraction of renal arterial rings in control (db/m+) mice and type 2 diabetic (db/db) mice was measured by a Multi Myograph System. Intracellular calcium concentration ([Ca 2+ ] i ) in vascular smooth muscle cells was measured by Fluo-4/AM dye and confocal laser scanning microscopy. Quantitative real-time PCR and Western blot analysis were used to determine gene and protein expression levels, respectively. A stable TXA 2 mimic U46619 caused markedly stronger dose-dependent contractions in the renal arteries of db/db mice than in those of db/m + mice. This response was completely blocked by a TXA 2 receptor antagonist GR32191 and significantly inhibited by U73122. U46619-induced vasoconstriction was increased in the presence of nifedipine in db/db mice compared with that in db/m + mice, whereas the response to U46619 did not differ between the two groups in the presence of SKF96365. Sarcoplasmic reticulum Ca 2+ release-mediated and CaCl 2 -induced contractions did not differ between the two groups. In db/db mice, store-operated Ca 2+ (SOC) entry-mediated contraction in the renal arteries and SOC entry-mediated Ca 2+ influx in smooth muscle cells were significantly increased. And the gene and protein expressions of TXA 2 receptors, Orai1 and Stim1 were upregulated in the diabetic renal arteries. Therefore the enhancement of U46619-induced contraction was mediated by the upregulation of TXA 2 receptors and downstream signaling in the diabetic renal arteries. [ABSTRACT FROM AUTHOR]

Visfatin correlates with inflammation and its levels in peripheral blood are associated with some inflammatory diseases. This study aimed to assess the relationship between plasma visfatin levels and conversion of laparoscopic cholecystectomy to open surgery in acute cholecystitis. One hundred and forty-six acute cholecystitis patients and 146 sex- and age-matched healthy controls were recruited and their plasma visfatin levels were determined using an enzyme immunoassay. 17 patients (11.6%) underwent conversion. Plasma visfatin levels were statistically significantly elevated in all patients (97.2 ± 41.8 ng/mL), those with (161.4 ± 71.3 ng/mL) or without conversion (88.7 ± 26.9 ng/mL), compared to controls (40.3 ± 13.3 ng/mL, all P < 0.001). A linear regression analysis showed that plasma visfatin levels were positively associated with plasma C-reactive protein levels ( t = 0.510, P < 0.001). A logistic-regression analysis showed that age [odds ratio (OR) 1.160, 95% confidence interval (CI) 1.011–1.332, P = 0.035] and plasma visfatin levels (OR 1.035, 95% CI 1.005–1.066, P = 0.022) appeared to be the independent predictors of conversion. A receiver operating characteristic curve analysis found that plasma visfatin levels predicted conversion with high area under curve (AUC) (AUC, 850; 95% CI, 0.781–0.903). The AUC of the visfatin concentration was similar to that of age (AUC, 0.738; 95% CI, 0.659–0.807) ( P = 0.188). Visfatin improved the AUC of age to 0.914 (95% CI, 0.856–0.954) ( P = 0.011) using a combined logistic-regression model. Thus, high plasma levels of visfatin are associated with systemic inflammation, and may independently predict conversion of laparoscopic cholecystectomy to open surgery in acute cholecystitis. [ABSTRACT FROM AUTHOR]

Abstract: Ranolazine is mainly used to treat patients with chronic stable angina in clinical practice. However, ranolazine does not lower significantly systemic blood pressure. The direct effect of ranolazine on vascular tone remains unknown. In the present study, we investigated the vascular effects and mechanisms of action of ranolazine in isolated rat intrarenal arteries. Rings of intrarenal arteries were mounted in a small vessel myography using two stainless steel wires for the measurement of isometric tension. L-type Ca2+ currents were recorded in isolated single renal arterial smooth muscle cells using patch clamp techniques in whole-cell mode. Ranolazine induced concentration-dependent relaxations in rings contracted with phenylephrine, but ranolazine failed to cause any relaxation in rings pre-contracted by U46619, 5-HT or endothelin-1. Ranolazine also induced relaxations in norepinephrine pre-contracted rings. Yohimbine failed to induce relaxation in rings pre-contracted by norepinephrine. Propranolol did not affect ranolazine-induced relaxation but the relaxant effect of ranolazine was much less than that of prazosin. Ranolazine-induced relaxations were slight but significantly attenuated by endothelial denudation. Partial inhibition was observed in endothelium-intact arteries exposed to a combination of iberiotoxin and apamin. Ranolazine at higher concentration (>30μM) inhibited Ca2+-induced contraction in a noncompetitive manner. Ranolazine reduced L-type Ca2+ currents at potentials between −30 and 50mV in isolated renal artery myocytes. Therefore it can be said that ranolazine has significant α1-adrenergic receptor and weak calcium channel antagonistic effects in rat intrarenal arteries. [Copyright &y& Elsevier]