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Self-calibrating luminescent thermometry employing luminescence within the optical transparency windows provides a promising prospect for temperature measurement in the biological fields. In this work, a new Nd3+/Yb3+-codoped metal–organic framework Nd0.95Yb0.05BPTC showing three-dimensional anionic network, obtained by reacting ligand [1,1′-biphenyl]-3,3′,5,5′-tetracarboxylic acid (H4BPTC) with Nd3+ and Yb3+ ions under solvothermal conditions, is reported. Upon 808 nm photoexcitation, Nd0.95Yb0.05BPTC simultaneously emits the characteristic near-infrared luminescence of Nd3+ and Yb3+ ions based on the efficient energy transfer from Nd3+ to Yb3+ ions. In addition, the emission intensity ratio of Yb3+ and Nd3+ shows good exponential-like response to temperature in the physiological range of 293–323 K. The feature properties of Nd0.95Yb0.05BPTC include near-infrared absorption and emission, favorable temperature sensitivity and accurate temperature uncertainty, as well as good chemical stability, making such system useful in biomedical applications.

Fabrication of dual-emitting materials for H2S sensing under environmental and biological conditions is currently of great interest. In this work, a new chemically stable metal supramolecular complex [Zn2(pda)2(H2O)3]·(H2O)0.5 (Znpda, pda = 1,10-phenanthroline-2,9-dicarboxylic acid), with accessible uncoordinated carboxylic oxygen sites, is solvothermally synthesized. It can serve as a host in luminescent hybrid composites. By incorporating Eu3+ and Cu2+ in the supramolecular coordination network, we obtained the dual-emitting hybrid material Eu3+/Cu2+@Znpda, which simultaneously shows intense ligand and weak Eu3+ emissions in HEPES buffer solution. Since H2S can easily chelate with Cu2+ and recover the blocked "antenna effect" between the ligand and Eu3+, Eu3+/Cu2+@Znpda possesses both the turn-on and ratiomectric fluorescence response to H2S. Accordingly, we designed an IMPLICATION logic gate for H2S recognition by employing the fluorescence intensity ratio between the ligand and Eu3+ as the output signal. In addition, Eu3+/Cu2+@Znpda shows a fast response (

Magnetic Resonance Imaging (MRI) is a kind of medical imaging technology used for diagnostic imaging of diseases, but its image quality may be suffered by the long acquisition time. The compressive sensing (CS) based strategy may decrease the reconstruction time greatly, but it needs efficient reconstruction algorithms to produce high-quality and reliable images. This paper focuses on the algorithmic improvement for the sparse reconstruction of CS-MRI, especially considering a non-smooth convex minimization problem which is composed of the sum of a total variation regularization term and a $\ell_1$-norm term of the wavelet transformation. The partly motivation of targeting the dual problem is that the dual variables are involved in relatively low-dimensional subspace. Instead of solving the primal model as usual, we turn our attention to its associated dual model composed of three variable blocks and two separable non-smooth function blocks. However, the directly extended alternating direction method of multipliers (ADMM) must be avoided because it may be divergent, although it usually performs well numerically. In order to solve the problem, we employ a symmetric Gauss-Seidel (sGS) technique based ADMM. Compared with the directly extended ADMM, this method only needs one additional iteration, but its convergence can be guaranteed theoretically. Besides, we also propose a generalized variant of ADMM because this method has been illustrated to be efficient for solving semidefinite programming in the past few years. Finally, we do extensive experiments on MRI reconstruction using some simulated and real MRI images under different sampling patterns and ratios. The numerical results demonstrate that the proposed algorithms significantly achieve high reconstruction accuracies with fast computational speed.

Fabrication of dual-emitting materials for H

We know that compressive sensing can establish stable sparse recovery results from highly undersampled data under a restricted isometry property condition. In reality, however, numerous problems are coherent, and vast majority conventional methods might work not so well. Recently, it was shown that using the difference between $\ell_1$- and $\ell_2$-norm as a regularization always has superior performance. In this paper, we propose an adaptive $\ell_p$-$\ell_{1-2}$ model where the $\ell_p$-norm with $p\geq 1$ measures the data fidelity and the $\ell_{1-2}$-term measures the sparsity. This proposed model has the ability to deal with different types of noises and extract the sparse property even under high coherent condition. We use a proximal majorization-minimization technique to handle the nonconvex regularization term and then employ a semismooth Newton method to solve the corresponding convex relaxation subproblem. We prove that the sequence generated by the semismooth Newton method admits fast local convergence rate to the subproblem under some technical assumptions. Finally, we do some numerical experiments to demonstrate the superiority of the proposed model and the progressiveness of the proposed algorithm.

The recent designed non-linear conjugate gradient method of Dai and Kou [SIAM J Optim. 2013;23:296–320] is very efficient currently in solving large-scale unconstrained minimization problems due to its simpler iterative form, lower storage requirement and its closeness to the scaled memoryless BFGS method. Just because of these attractive properties, this method was extended successfully to solve higher dimensional symmetric non-linear equations in recent years. Nevertheless, its numerical performance in solving convex constrained monotone equations has never been explored. In this paper, combining with the projection method of Solodov and Svaiter, we develop a family of non-linear conjugate gradient methods for convex constrained monotone equations. The proposed methods do not require the Jacobian information of equations, and even they do not store any matrix in each iteration. They are potential to solve non-smooth problems with higher dimensions. We prove the global convergence of the class of the pro...

Objective: This study was to investigate the underlying mechanisms of valsartan chronotherapy in regulating blood pressure variability.Methods: RT-PCR was used to assay clock genes expression rhythm in the hypothalamus, aortic vessels, and target organs after valsartan chronotherapy. WB was used to measure Period 1 (Per1), Period 2 (Per2) protein expression in aortic vessels, as well as to measure phosphorylation of 20-kDa regulatory myosin light chain (MLC20) in VSMCs.Results: Specific clock genes in the hypothalamus, and Per1 and Per2 in aorta abdominalis, exhibited disordered circadian expression in vivo. Valsartan asleep time administration (VSA) restored circadian clock gene expression in a tissue- and gene-specific manner. In vitro, VSA was more efficient in blocking angiotensin II relative to VWA, which led to differential circadian rhythms of Per1 and Per2, ultimately corrected MLC20 phosphorylation.Conclusion: VSA may be efficacious in regulating circadian clock genes rhythm, then concomitantly correct circadian blood pressure rhythms.

After several decades of aeromagnetic surveys, the measured data now cover nearly the entire Chinese continent and part of the China Sea. These data were first applied in this research and could provide important insights into the distribution of igneous rocks beneath the earth’s surface. Because different types of igneous rocks have a magnetic difference and produce distinct aeromagnetic anomalies on aeromagnetic ΔT image with reduction to the pole or other data calculating maps. By analyzing more than 240 thousand magnetic susceptibility data points and aeromagnetic anomalies of known igneous rocks in the Chinese continent, it was determined that mafic-ultramafic rocks commonly have a high magnetic susceptibility and cause linear and strong positive aeromagnetic anomalies. Intermediate-felsic rocks have a stable and low magnetic susceptibility and show a flat gradient variation and regular shape. Volcanic rocks have large variability in regard to magnetic susceptibility and romance; therefore, the aeromagnetic anomalies are always random or show variation within a planar area and decrease rapidly when an upward continuation is applied. Following the aeromagnetic data and calculating the maps of the vertical first order derivative and the tilt derivative, and combining this information with known outcrops of igneous rocks, we renewed the boundaries of 82 known mafic-ultramafic rocks, 228 known intermediate-felsic rocks and 131 known volcanic rocks. In addition, we newly mapped concealed igneous rocks of 203 mafic-ultramafic rocks, 2322 intermediate-felsic rocks and 494 volcanic rocks. The igneous rocks can be identified as nine ultra-mafic belts, 10 mafic belts (or regions), 27 intermediate-felsic belts and eight volcanic blocks. The results indicate that the mafic-ultramafic rocks are mainly distributed in Tibet, Erenhot of Inner Mongolia and northern Qilian and the smaller zones in the western Kunlun, Tianshan, western Junggar, eastern Tibet, Maqin in Gansu and the Ailao Mountain (Mtn.) areas. The mafic rocks are mostly outcropped in northern Tibet, southwestern Sanjiang, Kangdian in Sichuan, Baise and Rongjiang in Guangxi, Yinjiang in Guizhou, Dabashan Mtn., Southern Dabie Mtn, Bangbu in Anhui, Qiemo in Xinjiang. The intermediate-felsic rocks are mainly located in the orogenic system and rarely within the craton. Volcanic rocks are widely developed in eastern and western China such as the circumference of Songliao Basin, Erlian Basin, the southern Yellow Sea - Subei Basin, Bohai Bay Basin, eastern Zhejiang, the circumference of Hainan Island, southern Sichuan - northern Yunan, central Tibet, the Bachu area in Tarim Basin, Junggar Basin and Turpan-Hami Basin.

We review the latest aeromagnetic geological data of continental China. We discuss the latest achievements in geological mapping and the newly detected features based on aeromagnetic data. Using aeromagnetic data collected for more than 50 years, a series of 1:5000000 and 1:1000000 aeromagnetic maps of continental China were compiled using state-of-the-art digital technology, and data processing and transformation. Guided by plate tectonics and continental dynamics, rock physical properties, and magnetic anomalies, we compiled maps of the depth of the magnetic basement of continental China and the major geotectonic units, and presented newly detected geological structures based on the aeromagnetic data.

Background: Numerous clinical studies have evaluated valsartan and found more efficacious control of blood pressure (BP) variability when administered before sleep. The treatment leads to improved outcomes when compared to administration upon awakening. The mechanism underlying this etiology is not fully understood. The present study investigates the safety and efficacy of asleep administration of valsartan in spontaneously hypertensive rats (SHR) with a non-dipping blood pressure pattern compared to SHRs receiving administration during awake time. Materials and Methods: 84 Male SHRs and 28 male Wistar-Kyoto rats (WKY) were kept under a strict alternating 12-h light/dark cycle. WKYs were utilized as a non-disease control. Meanwhile, SHRs were randomly divided into three groups: untreated, Valsartan asleep administration (VSA) and Valsartan awake administration (VWA) respectively. The VSA group was treated with valsartan (30 mg/kg/d) after the light onset, while the VWA group was treated with valsartan (30 mg/kg/d) after light offset. Both groups were treated for 6 weeks. Tail artery blood pressure was measured every 4 h via a noninvasive tail cuff blood pressure measurement method. HE and Masson staining were used to evaluate any damage within the target organs. ELISA was used to determine the 24-h plasma renin-angiotensin system (RAS) concentration at 4-h intervals. Results: Based on our findings, VSA significantly reduced 24-h and evening mean BP and restored the abnormal circadian rhythm compared to VWA, which attenuated injuries in the majority of target organs except for the kidneys. Furthermore, VSA was found to activate RAS during the light cycle and inhibit it during the dark cycle. Conversely, VWA was found to deactivate RAS throughout the day which may be related to the circadian BP rhythm. Conclusion: VSA may be more efficacious than VWA in controlling BP, circadian BP rhythm and blood RAS rhythm. Recent cardiovascular outcome investigations substantiate that chronotherapy treatment might be a novel therapeutic strategy for hypertension therapy. Abbreviations: Angiotensin-converting enzyme (ACE); Angiotensin converting enzyme inhibitors (ACEIs); Angiotensin II (ANG II); Analysis of variance (ANOVA); Angiotensin receptor blockers (ARBs); Blood Pressure (BP); Calcium Antagonists Calcium Channel Blockers (CCB); Chronic kidney diseases (CKD); Sodium carboxyl methyl cellulose (CMC-Na); Cardiac mass index (CMI); Cardiovascular diseases (CVD); Diastolic blood pressure (DBP); Enzyme-linked immunosorbent assay (ELISA); Hematoxylin-eosin (H&E); Kidney mass index (KMI); Liver mass index (LMI); Mean arterial blood pressure (MAP); Plasma renin concentration (PRC); Renin-angiotensin system (RAS); Rennin (REN); Systolic blood pressure (SBP); Student-Newman-Keuls q test (SNK-q test); Spontaneous hypertension rats (SHR); Valsartan asleep Administration (VSA); Valsartan awake Administration (VWA); Wistar-Kyoto (WKY); Mesor (M); Amplitude (A); Phase (φ).

The degradation of biphenol A polycarbonate under the combined action of the photo- and thermal-irradiation in the presence of humidity and oxygen was studied by tensile testing and physicochemical characterizations. A ductile-brittle-ductile transition dissimilar to previously reported aging-induced-embrittlement (ductile-brittle transition) has been revealed in the present article. Further increasing aging time (longer than 650 h) after ductile-brittle transition leads to the rejuvenation in ductile rather than continuous deterioration. Occurring with the second brittle-ductile transition, a competition between oxidation-induced chain scission and crosslinking has also been recorded by FTIR and DSC. Meanwhile, SEM results exclude the possibility that the rejuvenation in ductile is from the change in surface morphology upon aging. Thus, the aging-induced ductile-brittle-ductile transition could result from, at least partly, the competition between oxidation-induced chain-scission and chain crosslinking.

Introduction of a UV absorbing group onto a polymer chain through covalent bonding greatly reduced the UV light transmittance of the resulting polylactide (PLA) film and preserved the high transparency to visible light. Compared to simply blending a UV absorber with a PLA matrix, covalent bonding of the UV absorbing group with polylactide enabled the prepared films to have better dispersion of the UV absorbing group, stable solvent resistance, better protection effect against UV damage and a slower rate of UV irradiated degradation, while the distribution of the UV absorbing group made no difference to the aforementioned properties. The degradation of both the PLA film covalently bonded with a UV absorbing group and the PLA/UV-absorber blended film followed the same mechanism as pure PLA films, in that the alkyl-oxygen bond broke first to produce acyl-oxygen and secondary carbon radicals, which then captured hydrogen to form carboxyl groups and alkyl groups at the end of the fractured polymer chain. More UV absorbing groups at the chain end were favorable for reducing UV transmittance, providing a better protection effect on the packaged probe, and slowing the UV irradiated degradation of PLA film. The thermal stability was dependent on the molecular weight of polylactide and was hardly affected by the introduction of the UV absorber or UV absorbing group.