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An artificial “salt-in-polymer” SEI was constructed on the surface of Li-MSiOx particles to maintain the structural integrity and inhibit the parasitic reaction at the electrode/electrolyte interface during cycling.

This article presents a theoretical time-domain analysis of lightning surge propagation on a multistage and multi-conductor tower. An extended traveling wave theory using electric scalar potential is introduced. The non-TEM wave propagation in the tower is characterized by time/position-variant transient impedance. The analytical formulas of the transient impedance are presented for any position/time in the tower, as well as those of the reflection coefficient at a discontinuity. The concept of primary and secondary waves is introduced to depict the multiple reflections in the tower. It is found that the primary current wave attenuates during its propagation in the tower, and is corrected by a factor when crossing over the discontinuity. A pair of secondary waves is generated at the discontinuity, similar to a center-fed dipole. The proposed method is applied to evaluate the lightning current in a two-stage tower. The result of the proposed method is of high consistency with the FDTD result. It is also observed that the secondary waves could be neglected if the reflection coefficient is small. The traditional transmission line theory could lead to a significant error of the current in the tower.

In order to solve the problem that the output voltage of bilateral LC -compensated capacitive power transfer (CPT) system varies with the variation of load and equivalent coupling capacitance, this article presented a parameter design method that maintained the output voltage constant and guaranteed a high power factor. The mathematical model of the bilateral LC -compensated CPT system was established. The characteristic of the primary and secondary LC -compensated network was analyzed, and then, the conditions remaining a constant output voltage with varying load and coupling capacitance were determined. The relationship between the power factor and the load versus equivalent coupling capacitance was given. With the proposed parameter design method, a 100-W bilateral LC -compensated CPT experimental setup was constructed. The output voltage changes from 55.0 to 58.7 V and the power factor varies from 0.902 to 0.977 when the load and coupling capacitance vary from 30.2 to $70.8~\Omega $ and from 310 to 1490 pF , respectively. Both the simulation and experimental results have verified the characteristic of constant output voltage and the effectiveness of the proposed parameter design method.

Previously, we have finished the total synthesis of lycojaponicumin A (2) via development of an efficient synthetic strategy using semipinacol rearrangement as a key step. In order to further demonstrate the generality of this synthetic route, herein, we report the total synthesis of another fawcettimine-type alkaloid sieboldine A (1) from the same intermediate, which possesses an A/B/D tricyclic ring system and vicinal quaternary centers of 1. The synthesis features late-stage site-selective redox reactions, Schmidt glycosylation cyclization, and highly selective transformations.

Focusing on the output voltage reduction caused by variation of the equivalent coupling capacitance in capacitive power transfer (CPT) system, this paper proposes a hybrid control strategy to achieve constant output voltage with the variation. The hybrid automata model is introduced for the cascaded CPT system considering the characteristics of higher order, nonlinear, multi-mode, continuous time and discrete states. The control process of the system is transformed into a selection of boundary transition conditions, which simplify the controller design and implementation. Then, a hybrid automata model of the system is established based on the theory of hybrid system, and the boundary transition of each mode of the system is given. The simulation and experimental results show that the proposed hybrid control strategy can keep the output voltage constant when the coupling capacitance of CPT system varies in a certain range.

A divergent synthetic approach to six Ganoderma meroterpenoids, namely ganocins A-C, ganocochlearins C and D, and cochlearol T, has been developed for the first time. This synthetic route features a two-phase strategy which includes early-stage rapid construction of a common planar tricyclic intermediate followed by highly selective late-stage transformations into various Ganoderma meroterpenoids. Key to the strategy are a bioinspired intramolecular hetero-Diels-Alder reaction and Stahl-type oxidative aromatization, allowing efficient formation of the common tricyclic phenol intermediate. A nucleophilic dearomatization of the phenol unit, combined with a regioselective 1,4-reduction of the resulting dienone, enabled rapid access to ganocins B and C. Additionally, site-selective Mukaiyama hydration, followed by an intramolecular oxa-Michael addition/triflation cascade, served as a key strategic element in the chemical synthesis of ganocin A.

Rapid construction of molecules bearing all-substituted quaternary stereocenters represents a highly significant but challenging task in organic synthesis. Herein, we report a novel palladium-catalyzed cascade between alkene-tethered aryl iodides and carbon monoxide, which has resulted in a practical and powerful method for the synthesis of complex polycyclic molecules containing aryl-substituted quaternary stereocenters. Mechanistic studies suggested that the reaction proceeded via a Heck-type carbonylative cyclization, followed by a ketene-involved Friedel–Crafts acylation.

Synthetic studies toward the daphnane and tigliane diterpenes, a large family of natural products from the plant families Euphorbiaceae and Thymelaeaceae, are reported. Retrosynthetic analysis traced these molecules back to an aromatic precursor and several routes were explored in the forward direction to access such motifs. Two strategies ultimately proved capable of forging complex 5,7,6-fused tricyclic ring systems, one of which proceeded in only seven steps.

When wirelessly supplying electric power to movable devices using capacitive power transfer (CPT) technology, the sudden move in and move out of the pickup will cause a sudden change to the system structure. As a result, the current and voltage of the inverter may increase dramatically, which may destroy the semiconductor switches or other circuit components, and the system may consume a lot of power after the pickup is removed. To address the issues, this paper proposes an F-type compensated CPT system based on the characteristics of the inductor–capacitor–inductor resonant network. A steady-state model of the proposed CPT system is established, and a set of design equations is provided. The feasibility and validity of the proposed topology and its parameter design method have been verified by the simulation and experimental results. It has demonstrated experimentally that the CPT prototype can be self-protected and automatically enter standby mode after the pickup is removed, and restore to deliver the required power (>25 W) to the load at a high power efficiency (>80%) after the pickup is moved back to the primary circuit, which are the inherent features of the proposed system rather than relying on any additional detection and control.

To investigate the role of microbiota in dentine formation and the characteristics of dental pulp stem cells (DPSCs) in mouse incisors.The influence of microbiota on dentine was detected via microcomputed tomography (microCT), microhardness testing and haematoxylin-eosin (HE) staining in incisors from germ-free (GF), specific pathogen-free (SPF) and conventionalised (ConvD) mice. Cell Counting Kit-8 (CCK-8) assay, alizarin red staining and expression of dentine sialophosphoprotein (DSPP), alkaline phosphatase (ALP) and bone sialoprotein (BSP) via real-time polymerase chain reaction (PCR) were used to evaluate the biological characteristics of DPSCs derived from mice of different microbiota status.MicroCT showed that the incisors in the GF and ConvD groups had comparable dentine thickness to those in the SPF group. Microhardness testing showed a lower dentine hardness value in GF incisors compared to SPF, while HE staining showed that GF incisors exhibited thicker predentine than SPF incisors. There was no difference between the ConvD and SPF groups. DPSCs from GF mice showed no significant difference in proliferation rate to SPF and ConvD DPSCs. DPSCs from GF mice formed less mineral deposition and expressed lower levels of osteo-/odontogenic differentiation-related genes including ALP, BSP and DSPP than SPF and ConvD DPSCs. The absence of microbiota in GF mice resulted in a lower dentine hardness value, thicker predentine and impaired osteo-/odontogenic differentiation capacity.The absence of microbiota impaired the dentine mineralisation and osteo-/odontogenic differentiation abilities of DPSCs.

To compare the biological characteristics of dental pulp stem cells (DPSCs) and inflamed dental pulp derived stem cells (I-DPSCs) in vitro and their regeneration potential in Beagle immature premolars.Pulpitis was induced in the premolars of one beagle dog by opening the pulp chamber for 2 weeks, and inflammation was histologically confirmed. DPSCs and I-DPSCs were isolated from normal and inflamed dental pulp, and cell morphology, expression of mesenchymal stem cell markers, clone formation ability, cell proliferation and osteogenic/odontogenic differentiation potential were compared. The dental pulp of 20 roots from 10 immature premolars was extracted and divided into two groups. DPSCs or I-DPSCs with scaffolds were transplanted into the root canals. The roots were extracted after 3 months, and pulp regeneration was evaluated by histological analysis. The data were statistically analysed using one-way ANOVA and a Student t test.Histological analyses showed lymphocyte infiltration and elevated TNF-α expression, which confirmed the diagnosis of pulpitis. I-DPSCs showed similar morphology, marker gene expression and clone formation ability but greater proliferation ability and osteogenic/odontogenic differentiation potential. Pulp-like tissue formation and bone- and dentine-like tissue deposition were observed in both DPSC- and I-DPSC-transplanted roots.DPSCs derived from inflammatory dental pulp tissue have similar biological characteristics to those from normal dental pulp and could mediate pulp and dentine regeneration in immature premolars.

In order to study the dynamic response of the operation tunnel lining and the accuracy of taking strains as the controlling parameter when the adjacent rock was blasted, field experiments were carried out based on the blasting excavation of a new closely spaced tunnel engineering in Zhangjiajie. Meanwhile, particle vibration velocity in the surrounding rock at different distances from the explosion source was simulated through the dynamic finite element method. On the basis of vibration velocity field measured and numerical calculated, the propagation process of shock wave and strains and stress state of existing operation tunnel lining were analyzed at the key position. The comparison with field monitoring data indicates that the maximum vibration speed occurs at the radial direction of tunnel wall facing the blasting side, making defects of the tunnel lining easy to deteriorate. The vibration velocity decreases nonlinear along with increase of distance away from explosion source. Impact on tunnel wall facing the blasting side and arch lining is more serious when the adjacent rock was blasted. Through the study, the vibration velocity and strains as double controlling factors are credible in the actual near distance blasting engineering. The work of the study can provide a significant reference to similar projects.

Different sources of mesenchymal stem cells (MSCs) may differ in their biological characteristics, which are important for their clinical application. In the present study, MSCs were isolated from human exfoliated deciduous teeth (SHED), bone marrow, gingival tissue and umbilical cord tissue, and their biological characteristics including surface markers, proliferation capacity, tumorigenicity and immunogenicity were analyzed by flow cytometric analysis, ELISA and co‑culture with human lymphocytes, respectively. The results indicated that all four types of stem cells obtained from different sources expressed MSC surface markers, and they did not show tumorigenicity either in vivo or in vitro. Stem cells from SHED exhibited the strongest proliferation capacity. Umbilical cord‑derived MSCs displayed the strongest immunomodulatory ability, while bone marrow MSCs exhibited the best antigen‑presenting potential in response to interferon‑γ stimulation. These results provide information on MSCs derived from different tissues, which may be helpful in their clinical application.

Two hole transporting materials (HTMs), SFX-PT1 and SFX-PT2, were designed and synthesized by combing a spiro[fluorene-9, 9′-xanthene] (SFX) core with tetra- phenothiazine substituted at the 2,2′,7,7′- and 2,3′,6,′7-positions, respectively. As comparison, a HTM with tetra-phenothiazine substituted at the 2,2′,7,7′-positions of a 9, 9′-spirobifluorene core (Spiro-PT) was also synthesized. Their photophysical and electrochemical properties, thermal stability and hole mobility were investigated. It was demonstrated that SFX-centered HTMs exhibited superior Stokes shift, thermal stability and hole mobility than those of Spiro-PT. Combining with the substituted positions modification, SFX-PT1 has the largest Stokes shift of 197 nm, the highest decomposition temperature of 435 °C and hole mobility of 2.08 × 10−3 cm2V−1S−1. Moreover, the energy levels of the HTMs were matched very well with that of CH3NH3PbI3. Our results indicated that SFX-centered, phenothiazole substituted HTMs might be potential candidates for efficient perovskite solar cells.

Surface modification of polyolefine separators for high performance lithium-ion batteries has been a worthwhile research topic. In this work, poly (poly (ethylene glycol) methacrylate) (PPEGMA) was firstly grafted onto polypropylene (PP) separator based on N-hydroxyphthalimide (NHPI) catalysis and activators regenerated by electron transfer atom transfer radical polymerization (ARGET-ATRP). Bis(2,2,2-trichloroethyl) azodicarboxylate (BTCEAD) was anchored on the surface of PP separators in the presence of NHPI. Then BTCEAD functionalized PP separator initiated the polymerization of PEGMA by ARGET-ATRP. Thus, structure controllable PPEGMA was grafted on the surface of PP separators. The results of contact angle and electrolyte uptake tests demonstrated that electrolyte wettability of PPEGMA functionalized PP separator has been significantly improved. Electrochemical measurements indicated that the ionic conductivity and discharge capacity retention of cells assembled with PPEGMA functionalized PP separators were distinctly higher than that of cells with pristine PP separator. Herein, we presented a new methodology with high efficiency to modify PP separators under mild condition, which was also applied to other polyolefine separator for high performance lithium-ion batteries. The proposed approach might have many other potential applications in membrane modification field.

To evaluate the mineralisation response of lipopolysaccharide (LPS)-induced dental pulp cells (DPCs) to betamethasone and the potential benefit of betamethasone application on the recovery of injured dental pulp.The proliferation influence of betamethasone on DPCs was analysed through the cell counting kit-8 assay. To assess the anti-inflammatory effects of betamethasone, the expression levels of inflammatory factors IL-6, IL-1ß and TNF-∂ were determined by real-time polymerase chain reaction (PCR). Mineralisation was investigated through the detection of the mineralisation-related biomarkers alkaline phosphatase (ALP), dentine sialophosphoprotein (DSPP) and osteocalcin (OCN) through the ALP activity assay, immunohistochemistry staining, Alizarin Red and tissue nonspecific alkaline phosphatase (TNAP) staining, the reverse transcriptase PCR technique and western blot.A low concentration of betamethasone (1 µ/mL) promoted the proliferation of DPCs. The real-time PCR results demonstrated that inflammatory cytokines were downregulated by betamethasone treatment. The mineralisation outcome in DPCs treated with betamethasone was better than in those treated without betamethasone.Betamethasone promoted the proliferation of DPCs. Betamethasone enhanced mineralisation in LPS-stimulated DPCs.

In the applications of wireless power transfer for mobile devices, the pick-up of the wireless power transfer system often needs to be moved in and moved out. A sudden change in the system structure will cause high transient voltages or currents, which could damage the power electronic device of the capacitive power transfer (CPT). In addition, the standby power of the system will be too high to work after removing the pick-up. A CPT system with double T-type resonant networks has been proposed to address these problems. The steady-state models of the system without the pick-up and normal state conditions of it are established. The relationships between the resonant network parameters are analyzed, and a systematic circuit parameter design method is provided. The proposed CPT topology and the parameter design method have been verified by simulation and experiment. The system not only achieved self-protection under severe load change but also entered standby mode automatically after the pick-up was moved out. Besides, the system is restored to the normal state condition when the pick-up is moved in without additional detection and control circuitry.

Multicomponent ring-opening/Huisgen cycloaddition reactions combined with CO2 capture with a polyurea-encapsulated copper salt as a catalyst that in situ formed from simple CuCl and soluble polyurea during the reaction were carried out successfully for the synthesis of β-hydroxytriazoles under exceptionally mild conditions, in which the polyurea-encapsulated copper(I) chloride proved to be a robust and recyclable catalyst system with high yields as well as excellent chemoselectivity in this reaction.

Herein, we report the first total syntheses of complex cephalotaxus diterpenoids cephanolide B and C from commercially available 5-bromo-2-methylanisole. Key to the success of this synthetic route is a palladium-catalyzed cascade cyclization reaction, which allowed us to efficiently forge the 6-5-6 cis-fused tricyclic ring systems found in the entire family of cephalotaxus diterpenoids. Additionally, site-selective late-stage sp

Aim To compare the efficacy of sodium hypochlorite (NaOCl) used at different concentrations and working times for removing necrotic periodontal ligament (PDL) from delayed replanted teeth and to observe the effects of NaOCl on surface structure and microhardness of cementum. Methodology A total of 88 healthy premolars with a single root extracted for orthodontic purposes were selected and kept dry at room temperature for 1 h. The teeth were divided into 11 groups: group 1 (control): roots were untreated; group 2: necrotic PDL was removed with gauze; groups 3–11: teeth were immersed in NaOCl at different concentrations (1, 2.5 and 5.25%) and for different working times (5, 10 and 15 min). The specimens in each group were inspected separately for cementum integrity and the presence of PDL remnants by histomorphometric analysis, confocal laser scanning microscopy (CLSM) and scanning electron microscopy (SEM). Another 14 healthy premolars with roots divided into two pieces were selected for Vickers microhardness indentation tests before and after NaOCl treatment. The data were analysed statistically using Wilcoxon signed-rank test of two-related samples (P = 0.05). Results In teeth treated with 1% NaOCl for 15 min or 5.25% NaOCl for 5 min, the cementum remained morphologically intact without cracks, and PDL remnants were absent. In the 1% NaOCl for 15 min group, the microstructure of cementum was arranged more regularly, as observed ×8000 magnification by SEM. Teeth in each of the other groups displayed cementum damage and/or the presence of PDL remnants. Microhardness tests revealed that treatment with 1% NaOCl for 15 min or 5.25% NaOCl for 5 min significantly decreased microhardness of root cementum (P

An enantioselective total synthesis of the polycyclic diterpene (+)-chatancin, a potent PAF antagonist, is reported. Proceeding in seven steps from dihydrofarnesal, this synthetic route was designed to circumvent macrocyclization-based strategies to complex, cyclized cembranoids. The described synthesis requires only six chromatographic purifications, is high yielding, and avoids protecting-group manipulations. An X-ray crystal structure of this fragile marine natural product was obtained.

Aiming at the problem of short transmission distance and low transmission efficiency, a parameter configuration method for the complementary symmetric LCC networks is proposed on the basis of the ECPT system with double-sided LC resonant network. The equivalent capacitance Cs is introduced into LC network to form LCC resonant network. Through the mechanism analysis and the parameter design of the forward LCC network, the constant voltage output of the forward LCC network is achieved; with the symmetric design of the inverse LCC network, the system characteristics including ZPA (zero phase angle) and constant current operation are obtained. The analytic relationship between the resonant operating point and system parameters is obtained by the stroboscopic map modeling method. Combining with the identification of Cs and variable frequency control, the system can still work steadily in ZPA state after Cs changes. The simulation and experimental results are in good agreement.

Based on low utilization rate of energy and high fuel consumption, a parallel hydraulic & electric configuration for hybrid excavator was proposed according to the capacitor and motor. The mathematical model of key components such as engine, electric motor, and capacitor were established. For the hybrid power system based on SUNWARD 20T hybrid excavator, the paper established simulation model and analyzed the energy saving effect of hybrid system by simulation based on the actual load spectrum of hydraulic excavator as input signal. The results indicate that adopting the parallel hybrid system are helpful to improve the energy saving effect of hydraulic excavator, and the energy saving efficiency is about 23.6%.

The optimal scheduling of crude-oil operation in refineries has been studied by various groups during the past decade leading to different mixed integer linear programming or mixed nonlinear programming formulations. This paper presents a new formulation with oil residency time constraint based on single-operation sequencing (SOS). It is different from previous formulations as it considers oil residency time constraint and pipeline transfer and does not require to postulate the number of priority-slots in which operations take place. This model is also based on the representation of a crude-oil scheduling by a single sequence of transfer operations. A simple MILP procedure has been used to solve this model leading to an satisfactory optimal result.

Aiming at problems of test, layout and application about campus network and combining with fundamental characteristic, introducing primary technology about transition from IPv4 campus network to IPv6 one, This paper discusses the status of IPv6 support technology and presents basic concept that campus network can be formed Gradually through layout testing network and experimental network; At the same time, in order to offer practical technical reference to favorable upgrading and applying campus network of ordinary universities It also discusses some services and applications about IPv6 campus network.

This article shows a composed method for modeling the concurrent execution of working processes in flexible manufacturing systems (FMS) by a special class of Petri nets named Resource Oriented Petri nets (ROPN). Essentially, the type of net comes from the availability of system resources. The analysis of ROPN is used to characterize deadlock situations in terms of full markings for certain structure named PPC. For the sake of preventing the system from deadlocks, a policy is proposed based on a series of restrictions for resource allocation, without considering the presence of unmarked siphons in Process Oriented Petri net (POPN). Finally, a control strategy of deadlock avoidance is designed for ROPN, which is better than other control policy.

The typical working condition and potentiality of energy recovery in construction machinery are discussed. Existing energy recovery techniques in the three types of technology platform are summarized with their features analyzed.The latest engineering results of energy recovery system are introduced. A preview of possible developments and challenge is presented finally. These work will provide useful information for energy recovery in construction machinery and contribute to the development of this field.

Background Historically, traditional Chinese medicine has been widely used to treat stroke. Based on the theory of Chinese medicine and the modern pharmacological knowledge of herbal medicines, we have designed a neuroprotective formula called Post-Stroke Rehabilitation (PSR), comprising seven herbs – Astragalus membranaceus (Fisch.) Bunge, Salvia miltiorrhiza Bunge, Paeonia lactiflora Pall., Cassia obtusifolia L., Ligusticum chuanxiong Hort., Angelica sinensis (Oliv.) Diels, and Glycyrrhiza uralensis Fisch. We aim to examine the neuroprotective activity of PSR in vitro and in vivo, and to explore the underlying molecular mechanisms, to better understand its therapeutic effect and to further optimize its efficacy. Methods PSR extract or vehicle was applied to primary rat neurons to examine their survival effects against N-methyl-d-aspartate (NMDA)-elicited excitotoxicity. Whole-cell patch-clamp recording was conducted to examine the NMDA-induced current in the presence of PSR. ERK- and CREB-activation were revealed by western blot analysis. Furthermore, PSR was tested for CRE promoter activation in neurons transfected with a luciferase reporter. The protective effect of PSR was then studied in the rat middle cerebral artery occlusion (MCAO) model. MCAO rats were either treated with PSR extract or vehicle, and their neurobehavioral deficit and cerebral infarct were evaluated. Statistical differences were analyzed by ANOVA or t-test. Results PSR prominently reduced the death of cultured neurons caused by NMDA excitotoxicity in a dose-dependent manner, indicating its neuroprotective property. Furthermore, PSR significantly reduced NMDA-evoked current reversibly and activated phosphorylation of ERK and CREB with distinct time courses, with the latter’s kinetics slower. PSR also triggered CRE-promoter activity as revealed by the increased expression of luciferase reporter in transfected neurons. PSR effectively reduced cerebral infarct and deficit in neurological behavior in MCAO rats when PSR decoction was administered starting either 6 days before or 6 h after onset of ischemia. Conclusions PSR is neuroprotective both in vitro and in vivo – it protects cultured neurons against NMDA excitotoxicity, and effectively reduces ischemic injury and neurobehavioral deficit in MCAO rats in both the pre- and post-treatment regimens. The underlying neuroprotective mechanisms may involve inhibition of NMDA receptor current and activation of ERK and CREB. This study provides important preclinical data necessary for the further development of PSR for stroke treatment. Electronic supplementary material The online version of this article (doi:10.1186/s12906-016-1417-1) contains supplementary material, which is available to authorized users.

Aiming at the issues of smooth transition from IPv4 to IPv6 and interoperability in technical coexistence period about campus network, discussing the technical characteristics of IPv6 protocol, GNS3 and OPNET simulator, combined with the status of weakness of IPv6 technology, lack of IPv6 technology planning and financial support for network upgrade in the vast majority of colleges, adopted the simulation methods to build a network model of IPv4 and IPv6 to achieve the technologies study such as topology design, network configuration and testing, network performance design and evaluation of IPv6 campus network under the low-cost conditions.

The supercharger technology of piston aviation engine determines its flight capabilities, and then establishes a turbocharger simulation model of an aviation piston engine. After simulating the engine ground features and 5000-meter altitude characteristics, and comparing the efficiency of compressor and turbocharger in different environments, after the installation of mechanical supercharger, gas flow has been improved, the cylinder pressure decreased about 10% compared with ground condition and engine altitude state power is restored, even 20,000 feet Power restored to 80%, which can meet the needs of high-altitude flight.

The homeobox, msh-like 1 (MSX1) protein is essential for cell proliferation and differentiation. Tooth germ development of Msx1 knockout mouse is arrested at the bud stage, impeding an understanding of its role beyond this stage of tooth development. The aims of this study were to investigate the potential role of MSX1 in the regulation of proliferation and differentiation of dental mesenchymal cells in culture, and to preliminarily explore its underlying mechanism of action. Tooth germs were isolated from embryonic day (E)15.5 mice. The mesenchyme was separated and digested into a single-cell suspension, and then cultured in vitro. Isolated dental mesenchymal cells were transfected with MSX1 small interfering RNA, and the effects on cell proliferation, cell cycle distribution, and the expression of bone morphogenetic protein 2 (Bmp2) and bone morphogenetic protein 4 (Bmp4) were studied. We also compared the expression levels of alkaline phosphatase (Alp), type I collagen (Col1A), osteocalcin (Ocn), runt-related transcription factor 2 (Runx2), dentin sialophosphoprotein (Dspp) and dentin matrix protein 1 (Dmp1), and mineralized nodule formation, between control and MSX1 siRNA-transfected groups after the induction of odontoblast differentiation. Knockdown of Msx1 expression was associated with decreased cell proliferation, prolonged time in the S phase of the cell cycle, enhanced odontoblast differentiation, and elevated Bmp2 and Bmp4 expression. We conclude that MSX1 may promote proliferation and prevent the differentiation of dental mesenchymal cells by the inhibition of Bmp2 and Bmp4 expression.

As one of the best image clustering methods, fuzzy local information C-means is often used for image segmentation. The effects of noise are avoided by utilizing the spatial relationship among pixels, but it often generates boundary zones for the mix pixels around the edges. This letter presents an image spatial clustering method, called fuzzy C-means with edge and local information (FELICM), which reduces the edge degradation by introducing the weights of pixels within local neighbor windows. The edges are extracted at first by Canny edge detection. During detection, two adaptive thresholds obtained by multi-Otsu method are used. Then, different weights are set according to whether the window center and the local neighbors are separated by an edge or not. Pixels, together with different weighted local neighbors, are clustered iteratively, until the final clustering result is obtained. The method can be directly applied to the image without any filter preprocessing, and the experimental results over remote sensing images show that FELICM not only effectively solves the problem of isolated and random distribution of pixels inside regions but also obtains high edge accuracies.

A process for the synthesis of α,α-difluoro esters by NHC-catalyzed fluorination is described. The internal redox process exhibits good efficiency, selectivity, and functional-group compatibility. It provides an alternative strategy for the formation of the useful gem-difluoromethylene unit in organic molecules.