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With the construction of the power Internet of Things (IoT), communication between smart devices in urban distribution networks has been gradually moving towards high speed, high compatibility, and low latency, which provides reliable support for reconfiguration optimization in urban distribution networks. Thus, this study proposed a deep reinforcement learning based multi-level dynamic reconfiguration method for urban distribution networks in a cloud-edge collaboration architecture to obtain a real-time optimal multi-level dynamic reconfiguration solution. First, the multi-level dynamic reconfiguration method was discussed, which included feeder-, transformer-, and substation-levels. Subsequently, the multi-agent system was combined with the cloud-edge collaboration architecture to build a deep reinforcement learning model for multi-level dynamic reconfiguration in an urban distribution network. The cloud-edge collaboration architecture can effectively support the multi-agent system to conduct "centralized training and decentralized execution" operation modes and improve the learning efficiency of the model. Thereafter, for a multi-agent system, this study adopted a combination of offline and online learning to endow the model with the ability to realize automatic optimization and updation of the strategy. In the offline learning phase, a Q-learning-based multi-agent conservative Q-learning (MACQL) algorithm was proposed to stabilize the learning results and reduce the risk of the next online learning phase. In the online learning phase, a multiagent deep deterministic policy gradient (MADDPG) algorithm based on policy gradients was proposed to explore the action space and update the experience pool. Finally, the effectiveness of the proposed method was verified through a simulation analysis of a real-world 445-node system. [ABSTRACT FROM AUTHOR]

This article concerns the dynamical transitions of the stochastic Swift-Hohenberg equation with multiplicative noise on a two-dimensional domain (−L, L) × (−L, L). With α and L regarded as parameters, we show that the approximate reduced system corresponding to the invariant manifold undergoes a stochastic pitchfork bifurcation near the critical points, and the impact of noise on stochastic bifurcation of the Swift-Hohenberg equation. We find the approximation representation of the manifold and the corresponding reduced systems for stochastic Swift-Hohenberg equation when L2 and √ 2L1 are close together. [ABSTRACT FROM AUTHOR]

In this article, we define the Hilbert-valued stochastic calculus with respect to G-Brownian motion in G-framework. On that basis, we prove the existence and uniqueness of mild solution for a class of neutral stochastic partial functional integro-differential equations driven by G-Brownian motion with non-Lipschitz coefficients. Our results are established by means of the Picard approximation. Moreover, we establish the stability of mild solution. An example is given to illustrate the theory. [ABSTRACT FROM AUTHOR]

In this paper, we first present an explicit exact solution to the edge wave problem in stratified geophysical flows with an underlying longshore current. Then we analyze the short-wavelength perturbation approach for barotropic incompressible fluids. Finally, we prove, by applying this method to geophysical equatorial edge waves in the background flow, that these waves are unstable when their steepness exceeds a specific threshold. [ABSTRACT FROM AUTHOR]

Sunitinib, an oral tyrosine kinase inhibitor, has been approved by the US Food and Drug Administration for the treatment of metastatic renal cell carcinoma and imatinib-refractory gastrointestinal stromal tumor. In non-gastrointestinal stromal tumor soft tissue sarcomas, the activity of this small-molecule drug has been rarely reported. Herein, we report a patient with lung metastases from renal leiomyosarcoma who responded favorably to sunitinib after the failure of conventional chemotherapy. Adverse effects of sunitinib, which include fatigue, hand-foot syndrome, and stomatitis were observed following its administration. Withdrawal of sunitinib led to progression of disease, and resuming use of sunitinib was still effective for multiple lung metastases. Sunitinib might be an effective treatment for renal leiomyosarcoma, especially when conventional chemotherapy fails. [ABSTRACT FROM AUTHOR]

In this article, we consider a nonlinear evolution equation for surface waves in shallow water over periodic uneven bottom. The local well-posedness in Sobolev space Hs (&#120138) with s 3/2 is established by applying Kato's theory. Then a blow up criterion is determined in Hs (&#120138), s > 3/2. S Finally, some blow-up results are given for a simplified model. [ABSTRACT FROM AUTHOR]

We prove the uniqueness of weak solutions of the 3D time-dependent Ginzburg-Landau model for superconductivity with L³ initial data in the case of Coulomb and type I Lorentz gauges. [ABSTRACT FROM AUTHOR]

In this paper, we consider the nonlocal parabolic equation ut = Δu + λH(1 - u)/(∫Ap,R H(1 - u)dx)², x ∈ Ap,R ⊂ ℝ², t > 0, with a homogeneous Dirichlet boundary condition, where λ is a positive parameter, H is the Heaviside function and Ap,R is an annulus. It is shown for the radial symmetric case that: there exist two critical values λ* and λ*, so that for 0 < λ < λ*, u(x, t) is global in time and the unique stationary solution is globally asymptotically stable; for λ* < λ < λ* there also exists a steady state and u(x, t) is global in time; while for λ > λ* there is no steady state and u(x, t) "blows up" (in some sense) for any appropriate (u0 (x) ≤ 1) initial data. [ABSTRACT FROM AUTHOR]

This paper is concerned with the asymptotic behavior of the solutions u(x,t) of the Swift–Hohenberg equation with quintic nonlinearity on a one-dimensional domain (0, L). With α and the length L of the domain regarded as bifurcation parameters, branches of nontrivial solutions bifurcating from the trivial solution at certain points are shown. Local behavior of these branches are also studied. Global bounds for the solutions u(x,t) are established and then the global attractor is investigated. Finally, with the help of a center manifold analysis, two types of structures in the bifurcation diagrams are presented when the bifurcation points are closer, and their stabilities are analyzed. [ABSTRACT FROM AUTHOR]

We consider the regularity of weak solutions to the Navier-Stokes equations in ℝ³. Let u := (u1, u2, u3) be a weak solution and ũ := (u1, u2, 0). We prove that u is strong solution if Δ ũ satisfy Serrin's type criterion. [ABSTRACT FROM AUTHOR]

The quasigeostrophic model is a simplified geophysical fluid model at asymptotically high rotation rate or at small Rossby number. We consider the quasigeostrophic equation with no dissipation term which was obtained as an asymptotic model from the Euler equations with free surface under a quasigeostrophic velocity field assumption. It is called the Hasegawa-Mima-Charney-Obukhov equation, which also arises from plasmas theory. We use a priori estimates to get the global existence of strong solutions for an Hasegawa-Mima-Charney-Obukhov equation. [ABSTRACT FROM AUTHOR]

Objective: To analyze changes in immune functions by detecting lymphocyte subsets in the peripheral blood of residents in the vicinity of radon from hot springs. Methods: Two groups were randomly selected; 61 residents in the vicinity of the hot springs were assigned to the radon group, and 51 residents with a similar lifestyle and habits but no contact with hot springs were assigned to the control group. The percentages of lymphocyte subsets (CD3+, CD4+ CD8-, CD4-CD8+, CD4+/CD8+, and TCR/CD3) in the 2 groups were evaluated on a FACS Aria flow cytometer. The absolute values of lymphocytes (LYMPH#) and percentages of lymphocytes (LYMPH%) were measured by an automatic blood analyzer. Results: In the radon group, the numbers of CD3+ (Z = -0.140, P > .05) and CD4+CD8- (Z = -0.964, P > .05) T cells were higher, as compared with the controls, but this difference was not significant. In addition, the number of CD4-CD8+ (t= -2.141, P < .05) T cells was significantly lower in the radon group. Furthermore, the average ratios of CD4+/CD8+ (t= -2.201, P < .05) and TCR/CD3 (t = 2.047, P < .05) cells were significantly higher in the radon group than in the controls. Compared with the control group, the LYMPH# (t = -0.485, P > .05) and LYMPH% (Z = -0.835, P > .05) showed no significant change. Conclusion: Radon-rich hot springs could alter the proportions of lymphocyte subsets and possibly affect immunologic functions. [ABSTRACT FROM AUTHOR]

• Bladder cancer (BC) is a common type of urological cancer. • BC spreads via direct infiltration and lymphatic and hematogenous metastases. • Lymphatic metastasis is considered a poor prognostic factor for BC. • Several epigenetic factors are related to lymphatic metastasis in BC. • These epigenetic factors include microRNAs, long noncoding RNAs, and circular RNAs. Bladder cancer (BC), a malignancy originating in the epithelial tissue in the inner wall of the bladder, is a common urological cancer type. BC spreads through 3 main pathways: direct infiltration, lymphatic metastasis, and hematogenous metastasis. Lymphatic metastasis is considered a poor prognostic factor for BC and is often associated with lower survival rates. The treatment of BC after lymphatic metastasis is complex and challenging. A deeper understanding of the molecular mechanisms underlying lymphatic metastasis of BC may yield potential targets for its treatment. Here, we summarize the current knowledge on epigenetic factors—including miRNAs, lncRNAs, and circRNAs—associated with lymphatic metastasis in BC. These factors are strongly associated with lymphangiogenesis, cancer cell proliferation and migration, and epithelial–mesenchymal transition processes, providing new insights to develop newer BC treatment strategies. [Display omitted] [ABSTRACT FROM AUTHOR]

Background: Islet cell transplantation is an emerging therapy in the treatment of diabetes mellitus. Differentiation of islet cells from mesenchymal stem cells (MSCs) is a potential solution to the challenge of insufficient donor sources. This study investigated whether human umbilical cord‐derived MSCs could effectively differentiate into insulin‐producing cells (IPCs) and evaluated the therapeutic efficacy of IPCs in treating diabetes. Methods: IPCs were induced from MSCs by a two‐step protocol. IPC expression products were evaluated by western blot and real‐time PCR. IPC insulin secretion was evaluated by ELISA. The viability of IPCs was measured by FDA/PI and dithizone staining. The non‐human primate tree shrew was used as a diabetes model. After a single STZ induction into a diabetes model, a single intraportal transplantation of IPCs, MSCs, or normal saline was performed (n = 6 per group). Blood glucose was monitored for 3 weeks, then the animals were euthanized and the distribution of IPCs in the liver was examined pathologically. Results: After about 3 weeks of in vitro induction, IPCs formed microspheres of 100–200 μm, with >95% viable cells that were dithizone stain positive. IPCs expressed islet‐related genes and proteins and secreted high levels of insulin whether stimulated by low or high levels of glucose. After transplantation of IPCs into diabetic tree shrews, blood glucose levels decreased rapidly to near normal and were significantly lower than the MSC or saline groups for 3 weeks thereafter. Conclusion: We present the novel discovery that IPCs derived from human umbilical cord MSCs exert a therapeutic effect in a non‐human primate model of diabetes. This study provides a preliminary experimental basis for the use of autologous MSC‐derived IPCs in the treatment of human diabetes. [ABSTRACT FROM AUTHOR]

In this paper, we consider two types of solut ions of the rotation-two-component Camassa--Holm (R2CH) system, a model of equatorial water waves that includes the effect of the Coriolis force. The first type of solutions exhibits finite time singularity in the sense of wave-breaking. We perform a refined analysis based on the local structure of the dynamics to provide some criteria that leads to the blow-up of solutions. The other type of solutions we study is the solitary waves. We classify various localized solitary wave solutions for the R2CH system. In addition to those smooth solitary wave solutions, we show that there are solitary waves with singularities, like peakons and cuspons, depending on the values of the rotating parameter Ω and the balance index σ. We also prove that horizontally symmetric weak solutions of this model must be traveling waves. [ABSTRACT FROM AUTHOR]

The cyclization of α-alkynylzirconacyclopentenes in the presence of CuCl was achieved cleanly to afford stereodefined 3-ylidenecyclopentenes. Coupling of the copper intermediates with a variety of aryl iodides catalyzed by Pd(PPh 3) 4afforded bis-arylated ylidenecyclopentenes; however, in the absence of copper salts, the coupling reaction of the same zirconacycles with aryl iodides was efficiently promoted by Pd(OAc) 2/PPh 3in toluene to afford the monoarylated products. Activation of the central double bond of the cumulenic intermediate by a Pd(II) complex followed by nucleophilic attack of the Zr−sp 3carbon bond to form an alkenylpalladium intermediate accounting for this novel cyclization is suggested. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, we introduce a new method for investigating the rate of blow-up of solutions of diffusion equations with nonlocal nonlinear reaction terms. In some cases, we prove that the solutions have global blow-up and the rate of blow-up is uniform in all compact subsets of the domain. In each case, the blow-up rate of is precisely determined. [Copyright &y& Elsevier]

Proposes a model for the surface tension-driven Marangoni convection in the form of coupled Kuramoto-Sivashinsky and Ginzburg-Laundau type partial differential equations. Existence and uniqueness of global solutions of the model; Energy estimates required to complete the existence proof of global solutions.

Cluster of differentiation (CD) 147 is a transmembrane glycoprotein that is highly expressed at the tumor cell surface, which stimulates fibroblasts to produce a large number of matrix metalloproteinases and promotes tumor invasion and metastasis and tumor-induced angiogenesis. The present study investigated the functions and the role of CD147 in the human lung carcinoma A549 cell line. The present study constructed expression and interference [small interfering (si) RNA] lentiviral vectors of CD147, which established stable overexpression and low expression of CD147 in the A549 cell line, named A549-CD147 and A549-siCD147, respectively. The differences in biological features between various levels of CD147 expression in A549 cells was investigated by cell counting kit-8 (CCK-8), Transwell, scratch and lumen formation assays. The results of the CCK-8 assay revealed that A549-CD147 cell proliferation was significantly increased and A549-siCD147 cell proliferation was decreased compared with the control groups. The A549-CD147 cells had the largest number of cells penetrating the Matrigel in the Transwell assay, which indicates that upregulation of CD147 expression increases the infiltration capacity of cells. The scratch assay revealed that A549-CD147 cells have the highest capacity for migration, while A549-siCD147 cells have the lowest. Quantitative polymerase chain reaction and western blot analysis demonstrated that vascular endothelial growth factor (VEGF) expression was proportional to the expression level of CD147 at the mRNA and protein level. The lumen formation assay revealed that the number of vessel lumens that human umbilical vein endothelial cells formed in the A549-CD147 cell supernatant was increased compared with the A549-siCD147 cells. Collectively, the present results suggest that CD147 is important in the promotion of lung carcinoma cell proliferation, invasion and metastasis and the upregulation of VEGF, which stimulates the angiogenesis of lung carcinoma. In conclusion, CD147 may be a potential target in the treatment of lung carcinoma. [ABSTRACT FROM AUTHOR]

Isolation and quantification of soil organic matter (SOM) pools under the influence of management practices is needed for assessing the changes in soil fertility. However, the knowledge on how the active, slow and passive pools of SOM respond to long-term fertilization is scarce. Therefore, the present study was designed to isolate the active, slow, and passive pools of soil organic matter through physical fractionation under long-term fertilization. The treatments included; inorganic fertilization (NPK) either alone or combined with a normal dose of manure (MNPK) or a high dose of manure (1.5MNPK) with an unfertilized control (CK) for comparison. The isolated pools were analyzed and compared for their sizes, SOC and TN storage and their contribution to total SOC and TN sequestration. The results revealed that the fertilization enhanced the active, slow and passive pools of SOC and TN and their storage under applied treatments was patterned as 1.5MNK > MNPK > NPK > CK. The highest SOC and TN storage was observed in the active pool, while, greater response to fertilization (in terms of response ratio) was associated with the slow pool. Results show that fertilization enhanced the proportion of SOC and TN stocks to bulk SOC and TN stocks in active and slow pools, while a diminishing trend was found for passive pools. Moreover, the highest response ratio was found for TN sequestration in each pool as compared to SOC, suggesting preferential accumulation of TN over SOC in the studied soil. Nevertheless, the highest SOC and TN storage took place in the active pool. The slow pool showed greater response to applied fertilizer, with the highest values being observed under 1.5MNPK. This study concluded that long-term manure + inorganic fertilization is crucial for enhancing C and N sequestration by altering the size and response of SOM pools. [ABSTRACT FROM AUTHOR]

Dopinggraphene with boron has been difficult because of high reaction barriers.Here, we describe a low-energy reaction route derived from first-principlescalculations and validated by experiments. We find that a boron atomon graphene on a ruthenium(0001) substrate can replace a carbon bypushing it through, with substrate attraction helping to reduce thebarrier to only 0.1 eV, implying that the doping can take place atroom temperature. High-quality graphene is grown on a Ru(0001) surfaceand exposed to B2H6. Scanning tunneling microscopy/spectroscopyand X-ray photoelectron spectroscopy confirmed that boron is indeedincorporated substitutionally without disturbing the graphene lattice. [ABSTRACT FROM AUTHOR]

mi-122 may function as a novel tumor suppressor. Expression of mi-122 could suppress the proliferation of multi-kinds of human cancer cell lines. In this work, expression of mi-122 via adenoviral vector in non-small-cell lung cancer (NSCLC) cells reduces the number of invasion and migration cells. mi-122 attenuates the epithelial-mesenchymal transition process, which mediates cancer cells metastasis in NSCLC cells A549 and H460. The mechanisms data reveals that mi-122 would disrupt the epithelial-mesenchymal transition process by downregulating PI3K/AKT activation via reducing endogenous expression of insulin-like growth factor 1 receptor. These data highlight the detailed roles and potential application of mi-122 in NSCLC cells. [ABSTRACT FROM AUTHOR]

The moiré superstructure of a single layer of carbon on ruthenium, where 25×25 graphene honeycombs sit on 23×23 substrate unit cells, is determined from first principles. The density functional theory (DFT) calculations predict two kinds of structural units, Ω and Y, in the supercell, which are identified as moiré beatings or moirons. The related topographic bucklings, or “hills,” have distinct carbon conformations and a height of 1.16 Å. The different moirons are observed with scanning tunneling microscopy (STM), and surface x-ray diffraction (SXRD) also discriminates the two. This connects ab initio DFT calculations with STM and SXRD experiments in unit cells containing more than 4000 atoms. [ABSTRACT FROM AUTHOR]

Quantum oscillations of work function and film stability as a function of the film thickness in Pb thin films on Si(111) are measured directly using scanning tunneling microscopy and spectroscopy in order to determine their phase relationship. The comparison of the phase relationship in quantum oscillations (surface energy vs work function) reveals a complete surprise: In contrast to a theoretically predicted quarter wavelength phase shift in the phase relationship, we found that their quantum oscillations have identical phase for this particular system. A conjecture to resolve this contradiction is also provided. [ABSTRACT FROM AUTHOR]

Monodisperse Au, Ag, and Au3Pd nanoparticles (NPs) with narrow size distribution are prepared by direct reaction of the related metal salt with oleylamine in toluene. Oleylamine serves as both a reducing agent and a surfactant in the synthesis. The sizes and shape of these NPs are tuned by reaction temperatures. The hydrophobic oleylamine-coated NPs can be made water soluble by replacing oleylamine with 3-mercaptopropionic acid. Both surface plasmonic resonance (SPR) and surface enhanced Raman scattering (SERS) observed from the Au and Ag NPs are found to be NP size- and surface-dependent. [ABSTRACT FROM AUTHOR]

Boron carbide and silicon oxide (BCSiO) hetero-nanonecklaces have been successfully synthesized via temperature modulation. This kind of nanostructure was formed by coating 100−500 nm silicon oxide nanoballs onto 20−30 nm boron carbide nanowires. Synthetic analysis shows that a two-step model at different temperatures and the poor wettability between boron carbide and silicon oxide play important roles in the growth of hetero-nanonecklaces. Photoluminescence of the synthesized BCSiO hetero-nanonecklaces shows enhanced visible light emissions at 637.6 nm, which is attributed to the small size of the boron carbide nanowires and defects induced by silicon oxide sheaths. [ABSTRACT FROM AUTHOR]

Single-walled carbon nanotube (SWNT)−polymer composites have been fabricated to evaluate the electromagnetic interference (EMI) shielding effectiveness (SE) of SWNTs. Our results indicate that SWNTs can be used as effective lightweight EMI shielding materials. Composites with greater than 20 dB shielding efficiency were obtained easily. EMI SE was tested in the frequency range of 10 MHz to 1.5 GHz, and the highest EMI shielding efficiency (SE) was obtained for 15 wt % SWNT, reaching 49 dB at 10 MHz and exhibiting 15−20 dB in the 500 MHz to 1.5 GHz range. The EMI SE was found to correlate with the dc conductivity, and this frequency range is found to be dominated by reflection. The effects of SWNT wall defects and aspect ratio on the EMI SE were also studied. [ABSTRACT FROM AUTHOR]

Long-term fertilization has been recognized as a key factor controlling soil organic carbon (SOC) and crop yields at various scales. Therefore, the impact of long-term nutrient management on SOC contents, fractional distribution, C-mineralization, and crop productivity under maize mono-cropping was investigated in the present work. For this, a typical black soil in northeast China was collected and analysed to measure the organic carbon (OC) content in the bulk soil, the distribution and OC contents of the different SOC fractions including, coarse particulate organic carbon (cPOC) and free particulate organic carbon (fPOC), intra-aggregate particulate organic carbon (iPOC), free silt plus clay (s + c_f) and micro-aggregate derived silt plus clay (s + c_m), and the SOC mineralization dynamics under different fertilizer treatments. Treatments included: 1) unfertilized control (CK), 2) balanced mineral fertilization (NPK), 3) NPK combined with manure (MNPK), 4) NPK combined with high dose (1.5 times) of manure (1.5MNPK), and 5) NPK combined with crop straw (NPKS). Manure treatments (1.5MNPK and MNPK) led to the largest increase in the SOC content of bulk soil (97% for 1.5MNPK and 41% for MNPK respect to CK). In addition, the long-term fertilization improved the proportions of the cPOC, fPOC and iPOC, especially in the case of manure treatments. In this same way, in comparison to CK, manure treatments (1.5MNPK and MNPK) significantly increased the SOC contents in cPOC (by 96 and 57%, respectively), fPOC (by 146 and 91%, respectively), iPOC (by 160 and 113%, respectively), s + c_f (by 51 and 39%, respectively) and s + c_m (by 56 and 50%, respectively) fractions. Similarly, higher values of SOC mineralization were associated with the 1.5MNPK and MNPK treatments as compared to CK, NPKS, and NPK alone. Finally, the application of 1.5MNPK and MNPK resulted in the highest increase in maize grain yield and in straw biomass yield. Therefore, the results obtained clearly indicate that long-term fertilization using manure combined with mineral fertilizer is the best choice to improve the SOC sequestration and mineralization, as well as the crop yields. All these facts can be considered relevant from points of view related to environmental management, soil fertility, and cleaner crop production. [Display omitted] • 28 Years of organic and inorganic fertilization enhanced C-mineralization, corn biomass and physical protection of SOC. • cPOC was the primary fraction and physical protection was the main mechanism of SOC sequestration. • Manure application was the most influential strategy for enhanced crop biomass, C-mineralization and soil fertility. [ABSTRACT FROM AUTHOR]

The ordered PbTe/Pb quasi-one-dimensional nanowires array was electrodeposited on the SiO2/Si substrate. There are two essential factors for the formation of such kind of change in nanowire morphology and structure. One is the charges distribution at the tips of electrodeposit, the other one is the change in ion concentration in front of growth tip. We research the current versus bias voltage characteristics of single PbTe/Pb nanowire by four-probe scanning tunneling microscopy system. [ABSTRACT FROM AUTHOR]

Monodisperse Fe3O4nanoparticles are synthesized by a much simplified method of reductive decomposition of iron acetylacetonate in benzyl ether and oleylamine. The Fe3O4nanoparticles are catalytically active for CVD growth of 1D boron nanowires. [ABSTRACT FROM AUTHOR]

Flexible boron nanowires have been synthesized via thermoreduction in boron-oxygen compounds with magnesium. These as-prepared nanowires, which are structurally uniform and single crystalline, represent good semiconductor at high temperature. Tensile stress measurements demonstrate excellent mechanical property of boron nanowires as well as resistance to mechanical fracture even under a strain of 3%. Importantly, simultaneous electrical measurement reveals that the corresponding electrical conductance is very robust and remains constant under mechanical strain. Our results can be briefly explained by Mott’s variable range hopping model. [ABSTRACT FROM AUTHOR]

The article presents an experiment that uses a triphenylamine unit as the electron donor and two cyanovinyl groups as the electron acceptor to develop an ultra-high density storage technology. Due to the good hole-transporting ability of the triphenylamine group, it is anticipated to modify the electrical conductivity of the material. The new molecule enables the researchers to develop scanning tunneling microscopy (STM)-based storage by improving the stability of the thin film.

The article reports on the study on the importance of reversible, erasable and rewritable nanoscale recording on organic thin films in ultrahigh density information storage. The process involves the inducing of conductance transitions of the organic molecules through scanning tunneling microscope. Results show the possibilities for chemical modification of the rotaxane molecules.

This article focuses on a study related to stable, reproducible nanorecording on rotaxane thin films. Nanometer-scale recording on organic thin film media is a promising alternative to future ultrahigh-density information storage. Rotaxanes represent a new class of the super molecules and show stability at various chemical states in solution. Using scanning tunneling microscope (STM), researchers have achieved reproducible nanometer-scale recording on these films. Researchers utilized the conductance switching of the H1 thin films for STM-based nanorecording.

The hydrophilic hollow nano-spheres and hemispheres of Co are synthesized via ethylene glycol reduction of cobalt acetate in the presence of PVP and Pd nano-particle seeds. The dimensions of the hollow core can be tuned from 100 to 300 nm by controlling the amount of Pd nano-particle seeds. The morphology of the hollow materials strongly depends on the molar ratio of the amide unit in PVP over Co and the Mw of PVP. The hollow structure is formed when the ratio falls in the range 1-1.5 and the Mw is over 40 000. Based on the experimental data, a possible formation mechanism of Co hollow spheres is proposed. [ABSTRACT FROM AUTHOR]

In this paper, the local existence and blow-up for an initial boundary value problem of the Camassa-Holm equation are obtained. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]

In this paper the difference in the asymptotic dynamics between the nonlocal and local two-dimensional Swift-Hohenberg models is investigated. It is shown that the bounds for the dimensions of the global attractors for the nonlocal and local Swift-Hohenberg models differ by an absolute constant, which depends only on the Rayleigh number, and upper and lower bounds of the kernel of the nonlocal nonlinearity. Even when this kernel of the nonlocal operator is a constant function, the dimension bounds of the global attractors still differ by an absolute constant depending on the Rayleigh number. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]