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The functional maps framework has achieved remarkable success in non-rigid shape matching. However, the traditional functional map representations do not explicitly encode surface orientation, which can easily lead to orientation-reversing correspondence. The complex functional map addresses this issue by linking oriented tangent bundles to favor orientation-preserving correspondence. Nevertheless, the absence of effective restrictions on the complex functional maps hinders them from obtaining high-quality correspondences. To this end, we introduce novel and powerful constraints to determine complex functional maps by incorporating multiple complex spectral filter operator preservation constraints with a rigorous theoretical guarantee. Such constraints encode the surface orientation information and enforce the isometric property of the map. Based on these constraints, we propose a novel and efficient method to obtain orientation-preserving and accurate correspondences across shapes by alternatively updating the functional maps, complex functional maps, and pointwise maps. Extensive experiments demonstrate our significant improvements in correspondence quality and computing efficiency. In addition, our constraints can be easily adapted to other functional maps-based methods to enhance their performance. [ABSTRACT FROM AUTHOR]

Background: Pancreatic cancer-associated fibroblasts (CAFs) play a crucial role in tumor progression and immune evasion. Asperuloside (ASP) is an iridoid glycoside with potential anti-tumor properties. This study aimed to explore the molecular mechanisms of ASP on CAFs, particularly focusing on its effects on activating transcription factor 6 (ATF6), a key regulator of endoplasmic reticulum stress. Method: CAFs were treated with different concentrations of ASP (0, 1, 3, and 5 mM), and the role of ATF6 was investigated by over-expressing it in CAFs. Subsequently, western blot was used to detect ATF6, α-smooth muscle actin (α-SMA), fibroblast activating protein (FAP), and vimentin protein levels in CAFs. The collagen gel contraction assay and Transwell assay were applied to evaluate the contraction and migration ability of CAFs. In addition, the interleukin (IL)-6, C–C motif chemokine ligand (CCL)-2, and C-X-C motif chemokine ligand (CXCL)-10 levels were detected by reverse transcription-quantitative polymerase chain reaction (RT-qPCR). Results: CAFs had significantly higher expression levels of α-SMA, FAP, and vimentin compared to normal fibroblasts (NFs). ASP significantly inhibited the activation, contraction, and migration of CAFs in a concentration-dependent manner. ASP treatment also reduced the expression of cytokines (IL-6, CCL2, and CXCL10) and down-regulated ATF6 levels. Over-expression of ATF6 mitigated the inhibitory effects of ASP. Conclusion: ASP exerts its anti-tumor effects by down-regulating ATF6, thereby inhibiting the activation and function of pancreatic CAFs. These findings suggest that ASP could be a promising therapeutic agent for pancreatic cancer by modulating the tumor microenvironment. [ABSTRACT FROM AUTHOR]

In the work, thermal cycling reliability of graphene nanosheets-doped Sn–xAg–Cu/Cu solder joint (x = 1, 2, and 3 wt.%) was investigated. With different Ag content, Ag3Sn IMCs formed in solder matrix displayed different morphologies, number, and sizes. They played a synergistic role in enhancing the joint’s thermal cycling reliability with graphene nanosheets, the mechanism of which was fully clarified in our work. Experimental results showed that the increased Ag content and trace doping of graphene nanosheets into Sn–xAg–Cu/Cu solder joints enhanced their initial shear strength, thus allowing them to maintain a higher strength level during the whole thermal cycling. Electron Backscatter Diffraction results showed that graphene nanosheets-doped solder joints fractured from the solder matrix, and further from the interfacial IMC interlayer with a mixed feature of ductile and brittle. Increasing Ag content decreased the initial thickness of interfacial IMC layer via weakening the atom affinity of Sn and Cu, while forming more Ag3Sn strengthening phases. Doping graphene nanosheets further inhibited the growth of initial interfacial IMC layer and controlled the morphologies, number, and sizes of Ag3Sn phase during soldering and thermal cycling. As a result, they synergistically led to the delayed growth of interfacial IMC layer as well as matrix microstructure after thermal cycling, thus contributing to a slower decrease rate in shear strength. Theoretical calculation also showed a synergism contribution of graphene nanosheets and Ag3Sn phase, with the largest decrease ratio (19.8%) occurred in the average interfacial diffusion coefficient in Sn–1Ag–Cu. [ABSTRACT FROM AUTHOR]

We construct a novel descriptor called anisotropic wavelet energy decomposition descriptor (AWEDD) for non-rigid shape analysis, based on anisotropic diffusion geometry. We first extend the Dirichlet energy of the vertex coordinate function to an anisotropic version, then use multiscale anisotropic spectral manifold wavelets to decompose the Dirichlet energy to all vertices and collect local energy at each vertex to form AWEDD. AWEDD simultaneously encodes multiscale extrinsic and intrinsic shape features, which are more informative and robust than purely intrinsic or extrinsic descriptors. And the introduction of anisotropy endows AWEDD with stronger abilities of feature discrimination and intrinsic symmetry identification. Our results demonstrate that AWEDD is more discriminative than current state-of-the-art descriptors. In addition, we show that AWEDD is an excellent choice of the initial inputs for various shape analysis approaches, such as functional map pipelines and deep convolutional architectures. [ABSTRACT FROM AUTHOR]

A qualitative study was conducted in a secondary school to evaluate student learning processes and outcomes by examining their inquiry questions, journals, and maker artifacts in a curriculum-based maker learning environment supported by the Guided Inquiry Design (GID). Thirteen 8th-grade students in a suburban middle school in the southwest of the United States participated in the study. Inquiry questions, maker artifacts, and inquiry journals were collected and analyzed with rubrics that were developed based on a critical review of literature drawn from different bodies of literature. The objectives of this study were three-fold: (1) evaluate the quality of students' inquiry questions and maker artifacts, (2) assess students' internal knowledge representation (IKR) and external knowledge representation (EKR), and (3) develop a robust and valid assessment framework for maker learning considering students' expertise development over time. The findings revealed that the students progressed at different developmental levels; therefore, expertise development should be incorporated into the assessment framework for maker learning. This study also implied that scaffolding should be tailored to meet special needs of each student in a maker learning environment. The originality of this research is that the assessment framework takes into account individuals' development and progress towards expertise over time, instead of focusing on their learning outcomes at a specific time point. An additional value of this study is that the tools and supporting materials that serve as instructional scaffolds also serve as tools to collect evidence about student learning performance, processes, and outcomes. [ABSTRACT FROM AUTHOR]

Entecavir (ETV) and tenofovir disoproxil fumarate (TDF) are equally recommended as first-line treatments for antiviral treatment-naïve (ART-naïve) chronic hepatitis B (CHB) patients by practice guidelines because of their similarly high antiviral efficacy and low resistance rate. However, whether one is superior to the other in terms of hepatocellular carcinoma (HCC) prevention is currently largely controversial. We aimed to identify and synthesize these existing studies regarding the HCC risk of these two highly potent antivirals in treatment-naïve CHB patients. PubMed, EMBASE, and Cochrane Library were searched for studies between January 1, 2012 and June 25, 2022. These studies used ETV monotherapy and/or TDF monotherapy to treat ART-naïve CHB patients and reported the incidence of HCC. The extracted data were analyzed using a DerSimonian–Laird random-effects models. The HCC incidence difference was expressed as hazard ratio (HR) and 95% confidence interval (95% CI). A total of 17 studies with 90,897 ART-naïve CHB patients (ETV = 60,980 vs TDF = 29,917) were included in this meta-analysis. Compared with ETV, TDF was associated with a significant lower cumulative incidence of HCC (HR 0.66; 95% CI 0.56–0.76). No significant heterogeneity or publication bias was found among the included studies (I2 = 48.1%, Begg's p = 0.363 and Egger's p = 0.748). TDF is associated with a lower risk of HCC compared with entecavir in ART-naïve CHB patients. The results suggest that TDF may be a better option for ART-naïve CHB patients with high HCC risks. [ABSTRACT FROM AUTHOR]

Shape descriptors have recently gained popularity in shape matching, statistical shape modeling, etc. Their discriminative ability and efficiency play a decisive role in these tasks. In this paper, we first propose a novel handcrafted anisotropic spectral descriptor using Chebyshev polynomials, called the anisotropic Chebyshev descriptor (ACD); it can effectively capture shape features in multiple directions. The ACD inherits many good characteristics of spectral descriptors, such as being intrinsic, robust to changes in surface discretization, etc. Furthermore, due to the orthogonality of Chebyshev polynomials, the ACD is compact and can disambiguate intrinsic symmetry since several directions are considered. To improve the ACD's discrimination ability, we construct a Chebyshev spectral manifold convolutional neural network (CSMCNN) that optimizes the ACD and produces a learned ACD. Our experimental results show that the ACD outperforms existing state-of-the-art handcrafted descriptors. The combination of the ACD and the CSMCNN is better than other state-of-the-art learned descriptors in terms of discrimination, efficiency, and robustness to changes in shape resolution and discretization. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Acupuncture & Tuina Science is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Identifying, quantifying, and suppressing decoherence mechanisms in qubits are important steps towards the goal of engineering a quantum computer or simulator. Superconducting circuits offer flexibility in qubit design; however, their performance is adversely affected by quasiparticles (broken Cooper pairs). Developing a quasiparticle mitigation strategy compatible with scalable, high-coherence devices is therefore highly desirable. Here we experimentally demonstrate how to control quasiparticle generation by downsizing the qubit, capping it with a metallic cover, and equipping it with suitable quasiparticle traps. Using a flip-chip design, we shape the electromagnetic environment of the qubit above the superconducting gap, inhibiting quasiparticle poisoning. Our findings support the hypothesis that quasiparticle generation is dominated by the breaking of Cooper pairs at the junction, as a result of photon absorption by the antenna-like qubit structure. We achieve record low charge-parity switching rate (<1 Hz). Our aluminium devices also display improved stability with respect to discrete charging events. Quasiparticles, or broken Cooper pairs, are a major source of decoherence in superconducting qubits but their origin is debated. Pan et al. confirm the dominant mechanism due to photon absorption in the Josephson junction and demonstrate mitigation strategies based on tuning of the qubit geometry. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the effects of malondialdehyde (MDA) on the structure and protein degradation of myofibrillar protein (MP) from Coregonus peled. Results found that MDA enhanced the amino acid side chain and carbonyl content of MP as the concentration of MDA increased, while the thiol groups and tryptophan fluorescence intensity decreased gradually. Mild oxidation (1 mM MDA) produced molecular expansion and protein structural unfolding, as evidenced by surface hydrophobicity. Furthermore, high degree of oxidation (> 10 mM MDA) led to protein aggregation. Fourier transformed infrared spectroscopy further showed the decreases in α-helix from 19.17 to 17.40%, and the increases in β-sheet from 23.33 to 28.05%. SDS-PAGE showed that disulfide and other covalent bonds caused protein cross-linking and aggregation, and myosin heavy chain degradation. Protein oxidation enhanced the degradation of actin and troponin-T, but prevented the degradation of desmin, according to Western blot. These results indicate that MDA can alter the structural characteristics of MP, which has implications for protein degradation and provide a scientific foundation for the relationship between MP oxidation and protein degradation. [ABSTRACT FROM AUTHOR]

The SbPO4/C composite was prepared by electrospinning combined with calcination, and the pure SbPO4 was successfully synthesized by the solvothermal method. The obtained samples were characterized by various techniques such as X-ray diffraction (XRD), Raman spectra, scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The results showed that SbPO4/C composite took on morphology of nanofibers, while SbPO4 took on morphology of particles with different sizes, and the SbPO4/C composite had better electrochemical properties than those of pure SbPO4. At a current density of 0.1 Ag−1, the initial specific capacity of the SbPO4/C material was 1255.7 mAhg−1, which was much higher than that of pure SbPO4 (695.3 mAhg−1). After 200 cycles, the specific discharge capacity of the SbPO4/C composite could be maintained at 845.7 mAhg−1. Besides, the SbPO4/C composite also behaved good rate performance. Therefore, the SbPO4/C composite is a promising anode material for the lithium-ion battery. [ABSTRACT FROM AUTHOR]

Incorporating multiscale spectral manifold wavelets preservation into the functional map framework for shape correspondence achieves great results in terms of both efficiency and effectiveness. However, fixing the dimension of the spectral embedding strategy in iterations of optimization is troublesome, such as missing high-frequency information when the dimension is small or getting trapped in local minima at a high dimension. In this paper, we present a simple and efficient method for refining correspondences from low frequency to high frequency with a theoretical guarantee. We formulate a strong constraint where the multiscale spectral manifold wavelets should be preserved at each scale correspondingly in the case of the arbitrary dimension of spectral embeddings. To solve the formula, we deduce two relaxed optimization subproblems and propose an incremental alternating iterative algorithm between the spatial and spectral domains via spectral up-sampling and filtering, computing the functional maps and pointwise maps in turn. Our results demonstrate that our method is robust to noisy initialization and scalable with regard to shape resolutions. The deformable shape correspondence benchmark experiments show our method produces more accurate and smoother results than state of the arts. [ABSTRACT FROM AUTHOR]

Deterioration of aquatic ecosystems, as a consequence of human-induced disturbances, is a critical global concern. To fully understand the responses of aquatic systems to anthropogenic impacts, it is crucial to assess long-term changes in lakes. The water quality of Jili Lake, a large water body in northwest China, has deteriorated recently, owing to the growing impacts of regional warming and human activities. Thus, Jili Lake was a prime candidate for evaluation of historical multi-stressor impacts. Meteorological data, historical documents, and assemblages of cladoceran microfossils in the sediments of Jili Lake were employed to investigate changes in the cladoceran community over the past century, and to evaluate the response of that aquatic community to human activities. From the 1920s to the 1950s, species richness of the cladoceran community was high, which reflected conditions of relatively low human impact. From the 1960s to 1970s, a sharp decrease in Bosmina longirostris, a planktonic cladoceran species, suggested a decrease in water level as a result of dam construction and intensified water exploitation. Since the 1980s, the water level in the lake has been restored, but increased fish farming and construction of a water storage facility caused salinisation and eutrophication of Jili Lake. Accordingly, the cladoceran community displayed distinct signs of a regime shift, with a gradual transition to dominance of B. longirostris and a sharp decrease in littoral species (e.g. Leydigia leydigi, L. acanthocercoides, Alona quadrangularis, Alona affinis). Our results suggest that human-induced disturbances were the main factor that drove changes in the cladoceran community since about the mid-20th century. [ABSTRACT FROM AUTHOR]

Fracture system is an important factor controlling tight oil accumulation in the Triassic Chang 8 Member, southwestern Ordos Basin, China. A systematic characterization of the multi-scale natural fractures is a basis for the efficient tight oil production. Based on outcrops, seismic reflections, well cores, well logs (image and conventional logging), casting thin sections, and scanning electron microscope observation, the multi-scale fractures occurrences and their influences on Chang 8 tight sandstone reservoirs are revealed. The results show that three periods of strike-slip faults and four scales of natural fractures developed, namely mega-scale (length > 7 × 107 mm), macro-scale (3.5 × 105 < length < 7 × 107 mm), meso-scale (10 < length < 3.5 × 105 mm), and micro-scale (length < 10 mm) fractures. The mega- and macro-scale fractures developed by strike-slip faults are characterized by strike-segmentation and lateral zonation, which connect the source and reservoir. These scale fractures also influence the distribution and effectiveness of traps and reservoirs, which directly influence the hydrocarbon charging and distribution. The meso fractures include the tectonic, diagenetic, as well as hydrocarbon generation-related overpressure types. The meso- and micro-scale fractures improve the sandstone physical properties and also the tight oil well production performance. This integrated study helps to understand the distribution of multi-scale fractures in tight sandstones and provides a referable case and workflow for multi-scale fracture evaluation. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Acupuncture & Tuina Science is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this paper, we study and analyze the regularized least squares for function-on-function regression model. In our model, both the predictors (input data) and responses (output data) are multivariate functions (with d variables and d ˜ variables respectively), and the model coefficient lies in a reproducing kernel Hilbert space (RKHS). We show under mild condition on the reproducing kernel and input data statistics that the convergence rate of excess prediction risk by the regularized least squares is minimax optimal. Numerical examples based on medical image analysis and atmospheric point spread function estimation are considered and tested, and the results demonstrate that the performance of the proposed model is comparable with that of other testing methods. [ABSTRACT FROM AUTHOR]

To achieve a rapid and great enhancement in the flexural performance of reinforced concrete beams, this study proposes a new strengthening method using U-shaped steel casing and focuses on studying the fatigue performance of strengthened beams. In this paper, ten specimens were tested under fatigue loads. Testing results demonstrated that no obvious damage was observed from the strengthened beam after 2 million fatigue cycles compared with the reference beam which failed at 58.97 × 104 fatigue cycles, indicating the good joint performance of the U-shaped steel casing and the RC beam. The strengthened beams generally failed by the sudden rupture of the bottom steel plate accompanied by concrete crushing. The mid-span deflection and material strains all increased rapidly at the beginning, then steadily developed during nearly 80% of the fatigue life, and grew rapidly again after the weld toe cracking until the strengthened beam failed. The fatigue life was significantly extended with the increase of either the height of the steel box or the thickness of the bottom plate, while it was dramatically shortened with the increase in the fatigue load amplitude. To facilitate the use of the outcomes, a simplified formula for predicting the concrete residual strain of strengthened beams was derived. The predicted results matched the experimental ones well. The derived formula is theoretically only applicable to strengthened beams with dimensions same as the specimens in the experimental tests under similar loading conditions. Reasonably good agreements were found between the finite element analyses and experimental results. The developed finite element model can well simulate the failure mode under static load and the damage evolution under fatigue load. Based on the stress analysis results, the fatigue lives of the strengthened beams were predicted relatively accurately using the Fe-safe software, with the deviations mostly less than 15%. [ABSTRACT FROM AUTHOR]

Bismuth vanadate is considered to be a potential lithium-ion storage electrode material due to its high theoretical capacity and low theoretical platform. In this paper, BiVO4/carbon nanotubes (BiVO4/CNTs) composites were synthesized by a simple mixed solvothermal method. The performances of BiVO4/CNTs composites with different contents of CNTs were tested by battery test system. The BiVO4 composited with carbon nanotubes had high electrical conductivity and large Li+ diffusion coefficient, which lead BiVO4/CNTs (BVO/C) to behave better electrochemical properties than those of pure BiVO4. Particularly, the composite (BVO/C-2) owned the best performance among all samples of BVO/C. When the current density was 100 mA/g, its initial specific capacity was 956 mA h/g and kept at 984.3 mA h/g after 200 cycles. When the current density is 1 A/g, its specific capacity could keep at about 340 mA h/g after 700 cycles. Besides, the BVO/C-2 composite behaved good rate performances. The reasons for that the BVO/C-2 owned outstanding electrochemical properties were presented else. [ABSTRACT FROM AUTHOR]

The fully biodegradable polymer blends remain challenges for the application due to their undesirable comprehensive performance. Herein, remarkable combination of superior mechanical performance, bacterial resistance, and controllable degradability is realized in the biodegradable poly(L-lactide)/poly(butylene succinate) (PLLA/PBSU) blends by stabilizing the epoxide group modified titanium dioxide nanoparticles (m-TiO2) at the PLLA-PBSU interface through reactive blending. The m-TiO2 can not only act as interfacial compatibilizer but also play the role of photodegradation catalyst: on the one hand, binary grafted nanoparticles were in situ formed and stabilized at the interface to enhance the compatibility between polymer phases. As a consequence, the mechanical properties of the blend, such as the elongation at break, notched impact strength and tensile yield strength, were simultaneously improved. On the other hand, antibacterial and photocatalytic degradation performance of the composite films was synergistically improved. It was found that the m-TiO2 incorporated PLLA/PBSU films exhibit more effective antibacterial activity than the neat PLLA/PBSU films. Moreover, the analysis of photodegradable properties revealed that that m-TiO2 nanoparticles could act as a photocatalyst to accelerate the photodegradation rate of polymers. This study paves a new strategy to fabricate advanced PLLA/PBSU blend materials with excellent mechanical performance, antibacterial and photocatalytic degradation performance, which enables the potential utilization of fully degradable polymers. [ABSTRACT FROM AUTHOR]

The brain is the most important organ of mammals. The infinitely complex network of special synaptic connections constitutes the main body of the brain. The neural loop is the basis of brain function. Therefore, revealing the anatomical structure of the cerebral nerve circuit contributes to an in-depth understanding of the mechanism of brain information processing. Visual labeling is a basic approach for analyzing neurons and neural loops. Undoubtedly, The development of modern molecular genetic technologies promotes virus tracer technologies, which triggers the great advance of neural circuit-tracing technology. In this paper, we reviewed the latest development of commonly used neural circuit tracers, and the basic biological characteristics of neurotropic viruses, the genetic modification of virus tracer tools and neural circuit tracking strategies. We aim to introduce novel strategies for brain science research. [ABSTRACT FROM AUTHOR]

RBF-based methods play a very important role in the point cloud reconstruction field. However, solving a linear system is the bottleneck of such methods, especially when there are a large number of points and lead the computing to be time-consuming and unstable. In this paper, we firstly construct a novel implicit progressive-iterative approximation framework based on RBFs, which could elegantly reconstruct curves and surfaces or even higher dimensional data in an approximation or interpolation way, avoiding expensive computational cost on solving linear systems. Then, we further accelerate the proposed method with a strategy inspired from the conjugate gradient algorithm. In our framework, using proper RBFs allows to simply transform the iteration matrix to be symmetrical and positive definite. Such a property contributes to reduce the computational cost greatly and produce high-quality reconstruction results. Plenty of numerical examples on various challenging data are provided to demonstrate our efficiency, effectiveness, and superiority to other methods. [ABSTRACT FROM AUTHOR]

Dementia is very common in the late stage of patient with Parkinson's disease (PD). We aim to explore its underlying pathogenesis and identify candidate biomarkers using untargeted metabolomics analysis. Consecutive PD patients and healthy controls were recruited. Clinical data were assessed and patients were categorized into Parkinson's disease without dementia (PDND) and Parkinson's disease dementia (PDD). Fast plasma samples were obtained and untargeted liquid chromatography-mass spectrometry-based metabolomics analysis was performed. Based on the identified differentially-expressed metabolites from the metabolomics analysis, multivariate linear regression analyses and receiver operating characteristic (ROC) curves were further employed. According to the clinical data, the mean ages of PDND and PDD patients were significantly higher than those of healthy controls. The incidence of hypercholesterolemia was decreased in PDD patients. PDD patients also had lower levels of triglyceride, low-density lipoprotein cholesterol, and apolipoprotein B. There were 24 and 57 differentially expressed metabolites in PDD patients when compared with the healthy controls and PDND patients from the metabolomics analysis. Eleven lipid metabolites were simultaneously decreased between these two groups, and can be further subcategorized into fatty acyls, glycerolipids, glycerophospholipids, sphingolipids, and prenol lipids. The plasma levels of the eleven metabolites were positively correlated with MMSE score and can be candidate biomarkers for PDD patients with areas under the curve ranging from 0.724 to 0.806 based on the ROC curves. Plasma lipoproteins are significantly lower in PDD patients. A panel of eleven lipid metabolites were also decreased and can be candidate biomarkers for the diagnosis of PDD patients. Lipid metabolic dysregulation is involved in the pathogenesis of Parkinson's disease dementia. [ABSTRACT FROM AUTHOR]

The direct magnetoelectric (ME) coupling of Pb(Zr0.52Ti0.48)O3/LaNiO3/Ni (PZT/LNO/Ni) heterostructure was studied, which is prepared with the combination of sol–gel spin-coating method (for PZT) and off-axis magnetron sputtering (for LNO). LNO served as the buffer layer for the ferroelectric film and effective stress transfer can be realized between Ni foil and PZT film. Structural and morphological characterization was carried out for the as-grown PZT/LNO/Ni film-electrode-substrate heterostructure. Well-defined ferroelectric and magnetic hysteresis loops demonstrated the good ferroelectric and magnetic property. A large voltage ME coefficient of 560 mV cm− 1 Oe− 1 was observed at the relatively low bias magnetic field (Hdc) (~ 65 Oe) with LNO buffer layer thickness of ~ 15 nm in PZT/LNO/Ni heterostructures, which is 2 times higher than that observed in the PZT/Ni composite and provides great opportunities for the new generation sensor apparatuses that depend on direct ME effect. The results indicated the strain-mediated magnetoelectric coupling between ferroelectric PZT film and magnetic Ni foil. [ABSTRACT FROM AUTHOR]

Nitrogen (N) deficiency is one of the factors limiting crop productivity worldwide. As major forms of N, nitrate (NO3−) and ammonium (NH4+) regulate plant growth as signals. Although there are abundant studies on the response of many plants to N stress, the mechanism by which wheat (Triticum aestivum L.) roots adapt to low N, especially to low-NH4+ stress, has not been fully elucidated. In this study, wheat seedlings were planted in 1/2-strength Hoagland's solution containing 5 mM NO3−, 0.1 mM NO3−, or 0.1 mM NH4+ to characterize root physiological responses to N deficit. Under low-N stress, root fresh weight, lateral root number increased compared with those under control conditions. Moreover, the concentrations of indole-3-acetic acid (IAA), cytokinins (CKs), gibberellin (GA3), and jasmonic acid (JA) increased, while the salicylic acid (SA) concentration decreased under low-N stress. Assays using enzyme-linked immunosorbent assay (ELISA) and non-invasive micro-test technology (NMT) showed that H+-ATPase activity, the H+ efflux, and the IAA influx increased, while N influx decreased under low-N stress. Further study revealed that low-NO3− stress increased nitrate reductase and glutamine synthetase activities, while low-NH4+ stress increased the activities of glutamine synthetase and glutamate synthase. In conclusion, low-N stress altered root IAA, CKs, GA3, JA, and SA concentrations; increased H+-ATPase activity and H+ efflux; promoted an increase in lateral root number and thus N absorption area. Besides, low-N stress increased the activities of key enzymes related to N assimilation, promoted protein biosynthesis, and ultimately enhanced root growth. [ABSTRACT FROM AUTHOR]

Many anti-inflammatory therapies targeting neutrophils have been developed so far. A sialic acid (SA)–modified liposomal (SAL) formulation, based on the high expression of L-selectin in peripheral blood neutrophils (PBNs) and SA as its targeting ligand, has proved to be an effective neutrophil-mediated drug delivery system targeting rheumatoid arthritis (RA). The objective of this study was to investigate the influence of particle size of drug-carrying SALs transported and delivered by neutrophils on their anti-RA effect. Dexamethasone palmitate–loaded SALs (DP-SALs) of different particle sizes (300.2 ± 5.5 nm, 150.3 ± 4.3 nm, and 75.0 ± 3.9 nm) were prepared with DP as a model drug. Our study indicated that DP-SALs could efficiently target PBNs, with larger liposomes leading to higher drug accumulation in cells. However, a high intake of large DP-SALs by PBNs inhibited their migration ability and capacity to release the payload at the target site. In contrast, small DP-SALs (75.0 ± 3.9 nm) could maintain the drug delivery potential of PBNs, leading to their efficient accumulation at the inflammatory site, where PBNs would be excessively activated to form neutrophil extracellular traps along with efficient payload release (small DP-SALs) and finally to induce excellent anti-RA effect. [ABSTRACT FROM AUTHOR]

Chongqing is one of the five provinces in China that has the highest incidence of acute hemorrhagic conjunctivitis (AHC). Data of AHC cases from 2004 to 2018 were obtained from National Notifiable Diseases Reporting Information System (NNDRIS). Descriptive statistical methods were used to analyze the epidemiological characteristics; incidence maps were used to reflect incidence trends in each district; spatial autocorrelation was used to identify hotspot regions and spatiotemporal patterns of AHC outbreaks; spatiotemporal scan were conducted to identify AHC clusters. A total of 30,686 cases were reported with an annual incidence of 7.04 per 100,000. The incidence rates were high in 2007 and 2014, and large epidemics were observed in 2010 with the seasonal peak in September. Individuals aged 10–19 years, males, students and farmers were the prime high-risk groups. Except for 2012 and 2013, the spatial distribution of AHC did not exhibit significant global spatial autocorrelation. Local indicators of spatial association showed that the high-risk regions are Chengkou and Wuxi. The spatiotemporal scan indicated that all clusters occurred in September 2010, and the high-incidence clusters were mainly distributed in the northeast of Chongqing. The results could assist public health agencies to consider effective preventive measures based on epidemiological factors and spatiotemporal clusters in different regions. [ABSTRACT FROM AUTHOR]

The formation heterogeneity is considered as one of the major factors limiting the application of foam flooding. In this paper, influences of formation properties, such as permeability, permeability distribution, interlayer, sedimentary rhythm and 3D heterogeneity, on the mobility control capability and oil displacement efficiency of foam flooding, were systematically investigated using 2D homogeneous and 2D/3D heterogeneous models under 120 °C and salinity of 20 × 104 mg/L. The flow resistance of foam was promoted as the permeability increased, which thus resulted in a considerable oil recovery behavior. In the scenario of the vertical heterogeneous formations, it was observed that the permeability of the high-permeable layer was crucial to foam mobility control, and the positive rhythm appeared favorable to improve the foam flooding performance. The additional oil recovery increased to about 40%. The interlayer was favorable for the increases in mobility reduction factor and oil recovery of foam flooding when the low permeability ratio was involved. For the 3D heterogeneous formations, foam could efficiently adjust the areal and vertical heterogeneity through mobility control and gravity segregation, and thus enhancing the oil recovery to 11%–14%. The results derived from this work may provide some insight for the field test designs of foam flooding. [ABSTRACT FROM AUTHOR]

Objective: To explore the ultrastructure characteristics of patients with dampness-heat of Pi (Spleen)-Wei (Stomach) syndrome (DHPW) and Pi-qi deficiency syndrome (PQD), both of which are Helicobacter pylori (Hp)-correlated gastric diseases (HPCG), and implicate a helpful hint for the clinical microcosmic syndrome differentiation. Methods: Fourteen gastric mucosa samples from 6 chronic gastritis (CG) and 6 active peptic ulcer (including 8 DHPW, 4 PQD) as well as 2 healthy volunteers were collected and tested for Hp infection. The ultrastructure of gastric mucosa was observed under the transmission electron microscope (TEM). Results: Among 14 gastric mucosa samples, 8 of them were Hp positive (6 DHPW and 2 PQD), which were all accordance with the results screened by supermicro-pathological method. Under TEM, the normal gastric mucosa, with tidy microvilli and abundant in mucus granules, mitochondria and rough endoplasmic reticulum distributed evenly, and with smooth nucleus membrane. But in those specimens of DHPW with Hp infection, microvilli were presented with burr shape. Especially, those samples from dampness-heat syndrome with predominant heat type (DHSH) patients were more obvious, with microvilli damaged, mitochondria concentrated and distributed in disorder, secretory tubule extended. In dampness-heat syndrome with predominant dampness type (DHSD) patients, mucus granules aggregated obviously, mitochondria swelled and blurred, and rough endoplasmic reticulum crowded. For 2 samples of DHPW without Hp infection, their microvilli were intact, with mitochondria increased and gathered but well-distributed, and secretory tubule extended mildly. In 2 PQD patients with Hp positive, the specimens of microvilli were sparse, and their mucus granules and mitochondria were decreased, with fractured crests and vacuole, secretory tubules extension to nucleus membrane, and rough endoplasmic reticulum extension in a pool-like way, and nucleus condensed. The 2 samples from PQD patients without Hp infection were characterized with intact microvilli, decreased mitochondria, fractured crest and extended rough endoplasmic reticulum in a pool-like way. Conclusion: It's obviously different in ultrastructure of DHPW and PQD patients under TEM, which may give a helpful hint for the microcosmic syndrome differentiation of HPCG. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Acupuncture & Tuina Science is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Purpose: The aim of this research was to design dexamethasone palmitate (DP) loaded sialic acid modified liposomes, with the eventual goal of using peripheral blood neutrophils (PBNs) that carried drug-loaded liposomes to improve the therapeutic capacity for rheumatoid arthritis (RA). Methods: A sialic acid – cholesterol conjugate (SA-CH) was synthesized and anchored on the surface of liposomal dexamethasone palmitate (DP-SAL). The physicochemical characteristics and in vitro cytotoxicity of liposomes were evaluated. Flow cytometry and confocal laser scanning microscopy were utilized to investigate the accumulation of liposomes in PBNs. The adjuvant-induced arthritis was adopted to investigate the targeting ability and anti-inflammatory effect of DP loaded liposomes. Results: Both DP-CL and DP-SAL existed an average size less than 200 nm with remarkably high encapsulation efficiencies more than 90%. In vitro and in vivo experiments manifested SA-modified liposomes provided a reinforced accumulation of DP in PBNs. As well, DP-SAL displayed a greater degree of accumulation in the joints and a stronger anti-inflammatory effect in terms of RA suppression. Conclusions: SA-modified liposomal DP was a promising candidate for RA-targeting treatment through the neutrophil-mediated drug delivery system. [ABSTRACT FROM AUTHOR]

The evolution of the microstructure and mechanical properties of a powder metallurgical (PM) high-speed steel (HSS) were investigated using a series of tempering times. A near Baker-Nutting (B-N) orientation relationship (OR) between the MC carbide and martensitic matrix was detected, while no OR between the M6C carbide and matrix was observed. The average grain size of the investigated alloys was approximately 4 to 6 μm, which was slightly larger than the thermodynamic calculated grain size of 2 μm. The results indicated that the Rockwell hardness, compressive strength, and in-situ nano-hardness of martensite decreased as the tempering times increased. After quadruple tempering, the fracture strain, compressive strength, and flexural strength declined. Triple tempering contributed to the superior combination of compressive strength, fracture strain, Rockwell hardness, and flexural strength of 3245 MPa, 30.6 pct, HRC 62.2, and 2094 MPa, respectively. The investigated alloys demonstrated strong susceptibility to cracks. The results of this study could provide useful information for the application of this HSS. [ABSTRACT FROM AUTHOR]

Macrophage-mediated drug delivery system has emerged and gained wide interest as a novel strategy for cancer treatment. Among them, RAW264.7 cell was commonly used as the macrophage model for antitumor drug loading and delivery. However, this cell line was a macrophage-like cancerous cell with both immunogenicity and pro-tumorigenic properties, which may interfere with the positive response of the host immune system to developed tumor. Thus, the safety and efficacy of the RAW264.7 cell line as a drug carrier for cancer therapy remain questionable. Here, we constructed doxorubicin-loaded RAW264.7 cells and examined its antitumor efficacy in S180 tumor-bearing mice. The bio-distribution of RAW264.7 cells was determined by in vivo imaging technique, showing a high accumulation level of RAW264.7 cells in mice livers, spleens, and thymuses. A phenomenon of accelerated tumor growth was observed in mice treated with doxorubicin-loaded RAW264.7 cells. Thereafter, the effect of frequency, dose, and viability of injected RAW264.7 cells on S180 tumor growth was further investigated. The underlying mechanism was confirmed, attributing to the immune tolerance induced by excessive RAW264.7 cells. Our findings emphasized the latent limitation of RAW264.7 cells as drug carrier in current researches, and provided an experimental basis for the clinical safety of cell-mediated drug delivery system. [ABSTRACT FROM AUTHOR]

As an irreversible small-molecule kinase inhibitor, ibrutinib (IBR) exhibits excellent tumor suppression in various tumor cells. However, IBR is insoluble at neutral pH and can dissolve only at low pH: thus, commercial IBR products present poor bioavailability and weakened in vivo antitumor activity. Therefore, we aimed to develop a stable IBR-phospholipid complex (IBR-PC) using egg phosphatidylglycerol (EPG) as excipients to improve the bioavailability of IBR and further enhance its antitumor effects. IBR-PC was characterized by transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC), X-ray powder diffraction (XPRD), and molecular docking and simulation test, which all explained the interactions of two components. Solubility tests demonstrate that the novel formulation can maintain excellent solubility (above 5 mg/mL) at various pH levels. Storage stability tests show that no change in particle size or content of IBR-PC was observed during the experimental period. In vivo pharmacokinetic results demonstrated that the relative bioavailability of IBR-PC was a 9.14-fold improvement relative to that of IBR suspension (IBR-susp). Furthermore, IBR-PC was associated with enhanced cytotoxic activity in vitro and superior tumor growth suppression in vivo compared to that resulting from the free IBR. Thus, the proposed IBR-PC system is a promising drug delivery system that enhances the oral bioavailability of IBR, resulting in its improved in vivo antitumor effect. [ABSTRACT FROM AUTHOR]

This paper presents a method for generating implicit surfaces from polygon soups based on compactly supported radial basis functions (CSRBFs). The surface is represented as the zero level set of an implicit function which interpolates the polygonal data with their outward normal constraints. By specifying two parameters, the support size and the shape parameter, users can flexibly control the accuracy of the reconstructed surfaces. For determining coefficients of RBFs, our method uses a quasi-interpolation framework to avoid solving a large linear system, which allows processing large meshes efficiently and robustly. Moreover, a relationship between the shape parameter and the support radius is provided for the quasi-solution validity, and an error bound of the reconstructed surfaces approximating the original models is deduced through the rigorous theoretical analysis. [ABSTRACT FROM AUTHOR]

Polysialic acid (PSA) is a nonimmunogenic and biodegradable polysaccharide. In recent years, PSA has shown its potential applications to cancer treatment. In this study, PSA-polyethylene glycol (PEG) conjugate was synthesized for the decoration of epirubicin (EPI)-loaded liposomes. The study aimed to evaluate the PSA-PEG conjugated modified liposomes (EPI-PSL) in vitro and in vivo to investigate the role of PSA on physicochemical characteristics and antitumor activity in PEGylated liposomes. EPI-PSL showed a particle size of 116.9 ± 5.2 nm, zeta potential of − 40.3 ± 3.5 mV, and encapsulation efficiency of 99.1 ± 1.5%. The results of in vitro release experiments showed a delayed release of EPI from EPI-PSL. Greater cellular uptake of EPI-PSL was observed compared with PEGylated liposomes (EPI-PL) in B16 cells. Cytotoxicity studies suggested that EPI-PSL exhibited stronger cytotoxic activity than EPI-PL. Though EPI-PSL exhibited comparable blood plasma profiles with EPI-PL, biodistribution studies proved that the distribution of EPI-PSL in tumors was more than that of EPI-PL. The superior antitumor efficacy of EPI-PSL was also verified in the B16 xenograft mouse model with a reduction in systemic toxicity. In conclusion, these results therefore indicated that PSA-modified PEGylated liposomes may represent an excellent anticancer drug delivery system for targeted cancer therapy. [ABSTRACT FROM AUTHOR]

Excessive proliferation of vascular smooth muscle cells is one of the main pathological processes leading to atherosclerosis and intimal hyperplasia after vascular interventional therapy. Our previous study has shown that interferon-γ inducible protein-10 contributes to the proliferation of vascular smooth muscle cell. However, the underlying mechanisms remain unclear. Extracellular signal-regulated kinase 1/2, serine/threonine kinase Akt, and cAMP response element binding protein are signaling pathways, which are considered to play important roles in the processes of vascular smooth muscle cell proliferation. Moreover, chemokine receptor 3 and Toll-like receptor 4 are potential receptors of inducible protein-10 in this process. In the present study, IP-10 was found to directly induce vascular smooth muscle cell proliferation, and exposure to inducible protein-10 activated extracellular signal-regulated kinase 1/2, serine/threonine kinase, and cAMP response element binding protein signaling. Inhibitor of extracellular signal-regulated kinase 1/2, rather than inhibitor of serine/threonine kinase, inhibited the phosphorylation of cAMP response element binding protein and reduced inducible protein-10-stimulated vascular smooth muscle cell proliferation. Knockdown of cAMP response element binding protein by siRNA inhibited inducible protein-10-induced vascular smooth muscle cell proliferation. Moreover, anti-CXCR3 IgG, instead of anti-Toll-like receptor 4 IgG, reduced inducible protein-10-induced vascular smooth muscle cell proliferation and inducible protein-10-stimulated extracellular signal-regulated kinase 1/2 and cAMP response element binding protein activation. Together, these results indicate that inducible protein-10 promotes vascular smooth muscle cell proliferation via chemokine receptor 3 and activation of extracellular signal-regulated kinase 1/2 inducible protein-10-induced vascular smooth muscle cell proliferation. These data provide important targets for future studies to modulate atherosclerosis and restenosis after vascular interventional therapy. [ABSTRACT FROM AUTHOR]

Purpose: Fractional flow reserve based on coronary computed tomographic angiography (CCTA; FFRCT) can evaluate functional severity in coronary artery disease (CAD). This study investigated the diagnostic value of FFRCT for determining CAD severity.Materials and Methods: Medline, Cochrane, EMBASE, and Google Scholar databases were searched until June 16, 2016 using the following search terms: fractional flow reserve, coronary computed tomography angiography, myocardial ischemia. Randomized controlled trials, two-arm prospective studies, and retrospective studies were included in the analysis.Results: Twenty-one studies were included with a total of 2216 subjects and 2798 vessels. FFRCT, sensitivity per-vessel and per-patient were ≥82% and specificity was ≥73% for diagnosis of ischemia. FFRCT had better diagnostic accuracy and discrimination than CCTA.Conclusion: This study indicates that FFRCT may be a good tool for screening and diagnosing of myocardial ischemia in patients with CAD. [ABSTRACT FROM AUTHOR]

Previous studies have demonstrated the effects of different afferent fibers on electroacupuncture (EA)-induced analgesia. However, contributions of functional receptors expressed on afferent fibers to the EA analgesia remain unclear. This study investigates the roles of acid-sensing ion channel 3 (ASIC3) and transient receptor potential vanilloid 1 (TRPV1) receptors in EA-induced segmental and systemic analgesia. Effects of EA at acupoint ST36 with different intensities on the C-fiber reflex and mechanical and thermal pain thresholds were measured among the ASIC3, TRPV1, and C57BL/6 mice. Compared with C57BL/6 mice, the ipsilateral inhibition of EA with 0.8 C-fiber threshold (0.8Tc) intensity on C-fiber reflex was markedly reduced in ASIC3 mice, whereas the bilateral inhibition of 1.0 and 2.0Tc EA was significantly decreased in TRPV1 mice. The segmental increase in pain thresholds induced by 0.3 mA EA was significantly reduced in ASIC3 mice, whereas the systemic enhancement of 1.0 mA EA was markedly decreased in TRPV1 mice. Thus, segmental analgesia of EA with lower intensity is partially mediated by ASIC3 receptor on Aβ-fiber, whereas systemic analgesia induced by EA with higher intensity is more likely induced by TRPV1 receptor on Aδ- and C-fibers. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Acupuncture & Tuina Science is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

To study the dispersity of different amine-graphene oxide (amine-GO) in polymer matrix and the interfacial interactions between functionalized graphene oxide and matrix, two kinds of modifiers-organoamine- and aminosilane-coupling agents-were used to functionalize graphene nanosheets to obtain functionalized graphene oxide/waterborne polyurethane nanocomposites by in situ polymerization. The chemical structure, morphology, and interlayer space of amine-GO nanoplatelets were confirmed by FT-IR, Raman, TGA, XPS, TEM, AFM, and XRD. The dispersity behaviors between different amine-GOs and polymers were evaluated by FESEM. The thermal, mechanical, and hydrophobic properties of the nanocomposites were investigated by TGA, tensile testing machine, and water contact angle test, respectively. It was found that the tensile strength of nanocomposites was increased from 10.13 to 27.79 and 28.96 Mpa after the addition of amine-GO functionalized by APTMS and APTES, respectively. The better thermal stability and hydrophobicity of nanocomposites were also achieved by the addition of amine-GO, especially those modified by aminosilane-coupling agents. This study paves a new route for designing and developing chemically converted graphene oxide nanosheets/polymer nanocomposite materials by altering suitable amine-modifier to functionalize graphene oxide nanosheets and then optimizing the interphases between graphene oxide nanosheets and polymer matrices. [ABSTRACT FROM AUTHOR]

Toxocara canis is an intestinal nematode of canids with a worldwide distribution, causing an important but neglected parasitic zoonosis in humans. Aquaporins (AQP) are a family of water channel proteins, which function as membrane channels to regulate water homeostasis. In this study, the coding sequence of aquaporin-1 gene of T. canis ( Tc-aqp-1) was cloned and characterized. The obtained Tc-aqp-1 coding sequence was 933 bp in length, which predicted to encode 311 amino acids. Two conserved asparagine-proline-alanine (NPA) motifs were identified in the multiple sequence alignments. Phylogenetic analysis revealed the closest relationship between T. canis and Opisthorchis viverrini based on aquaporin-1 amino acid sequence. A structure was predicted with ligand binding sites predicted at H93, N95, N226, L94, I79, and I210 and with active sites predicted at I256 and G207. Gene Ontology (GO) annotations predicted its cellular component term of integral component of plasma membrane (GO: 0005887), molecular function term of channel activity (GO: 0015250), and biological process term of water transport (GO: 0006833). Tissue expression analysis revealed that the Tc-aqp-1 was highly expressed in the intestine of adult male. The findings of the present study provide the basis for further functional studies of T. canis aquaporin-1. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Acupuncture & Tuina Science is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Acupuncture & Tuina Science is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The objective of this work is to investigate the fatigue behavior of reinforced concrete (RC) beams strengthened with externally bonded carbon fiber reinforced polymer (CFRP) and steel plate. An experimental investigation and theoretical analysis were made on the law of deflection development and stiffness degradation, as well as the influence of fatigue load ranges. Test results indicate that the law of three-stage change under fatigue loading is followed by both midspan deflection and permanent deflection, which also have positive correlation with fatigue load amplitude. Fatigue stiffness of composite strengthened beams degrades gradually with the increasing of number of cycles. Based on the experimental results, a theoretical model by effective moment of inertia method is developed for calculating the sectional stiffness of such composite strengthened beams under fatigue loading, and the calculated results are in good agreement with the experimental results. [ABSTRACT FROM AUTHOR]

The aim of the present study was to investigate the association of single nucleotide polymorphisms (SNP) of the microRNA-146a (miR-146a) genes with the risk of nonsmall cell lung cancer (NSCLC). The genotyping of miR-146a rs2910164 polymorphism was detected by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). The results showed that CC genotype and C allele distribution in the NSCLC patient were significantly higher than that of the controls ( P = 0.03 and 0.03, respectively). No significant differences were found between the two subgroups when stratified by clinical characteristics including age, sexual, smoke status, histological type, lymph node metastasis and clinical stage. In addition, the expression of miR-146a was detected by the Taqman real-time PCR. It demonstrated that the miR-146a expression was significantly decreased in NSCLC patients compared with that of nonmalignant lung tissues ( P = 0.01). In addition, the miR-146a expression of CC genotypes subgroup was significantly decreased than of GC/GG genotype subgroup in tumor tissues ( P = 0.0022). It confirmed that the SNP rs2910164 could functionally affect the miR-146a expression levels. In conclusion, it showed that the rs2910164 polymorphism of miR-146a is associated with the risk of NSCLC in the Chinese population. [ABSTRACT FROM AUTHOR]

Although the firing activity of dopamine (DA) neurons in the ventral tegmental area (VTA) and the behavioral response to morphine rewarding properties alter as opiate withdrawal, little is known about the dynamic changes in DA signal pathway from the VTA to the nucleus accumbens (NAc) during prolonged withdrawal, and whether the changes are indicative of vulnerability to relapse of drug abuse. Here we report that morphine spontaneously withdrawn (SW) rats are incapable of responding to small dose of morphine-induced conditioned place preference (CPP) from 24h-SW to 30d-SW, but recover response at 45d-SW. Interestingly, mesoaccumbens DA signaling, including the firing of DA neurons in the VTA, contents of DA and its metabolic ratio, and the membrane level of dopamine D receptor in the NAc elicited by morphine challenge, display a similar pattern of time-dependent changes during morphine withdrawal. Moreover, blockade of D receptor abolishes this behavioral transition. In addition, a strong correlation was found between % change in CPP score and membrane D receptor level induced by morphine challenge. These results indicate a time-dependent behavioral switch from tolerance to sensitization during the prolonged withdrawal, which could offer a window for therapeutic intervention via manipulations of D receptors. [ABSTRACT FROM AUTHOR]