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Here we take the self-assembly of porphyrin molecules as an example to discover the reason for the diversity of assembled structures. The self-assembly is conducted at a range of pH conditions. Irregular, tubular, and rodlike particles are formed at pH 1.5, 6.5 and 12.5, respectively. X-ray diffraction spectra and UV absorption show that these particles have the same crystalline structures, while the packing types of molecules are different. At low pH, the molecules assemble together by end to end attachment with a J-type aggregation, forming irregular particles. This assembly is dominated by the competition of π–π interaction and repulsion force. The latter force is induced by the protonation of molecules under acid conditions. With the increase of pH, the repulsion force is attenuated and finally disappears under basic conditions. The π–π interaction becomes the major force under basic conditions, leading to a H-type aggregation via face to face attachment and forming rodlike particles. At the middle pH...

Here we report a mechanistic study on the diversity of assembled structures. We take the assembly of porphyrin molecules as an example to investigate how the diffusion of molecules influences the structure of assemblies. The diffusion is regulated by changing the composition of solvents. Diverse structures of porphyrin particles are assembled at various volume ratios of ethanol in water, including strip-like particles forming at 50%, tubular particles forming at 80% and rod-like particles forming at 95%. The in situ examination on the self-assembly process by confocal microscopy reveals that at the low volume ratio the nucleation initiates at the interface of emulsion followed by the growth of particles in the solvent. The diffusion limitation of molecules in the solvent is remarkable at the low volume ratio of ethanol as a result of high viscosity of the solvent and low solubility to the molecule, which enables the anisotropic growth of particles forming strip-like particles. With the increase of volume ratio of ethanol, the diffusion limitation is attenuated, leading to the thickening of particles and the formation of rod-like products. The thickening under diffusion limitation also causes a preferential growth of outer layer of particles resulting in the formation of hollow structures. The findings in this paper show that the diffusion of molecules plays an important role in shaping structures of assemblies, which was underestimated in previous studies.

A dendrite is one of the most esthetically pleasing structures, with the best-known example being snowflakes. Although the formation of dendrites has been studied for centuries, the way to control their growth is limited. Here we report an attempt to manipulate the growth of dendritic structures via controlling chemical diffusion and reaction. The silver dendritic structures are synthesized by reducing silver ions in solution. The diffusion of chemical agents is regulated by changing the viscosity of the solution while the reaction is regulated by adding acids. The decrease of reaction rate leads to the disappearance of side branch of dendrites while the reduction of diffusion rate shortens the main trunk of dendrites. The silver dendrites are finely tuned by chemical diffusion and reaction. Following studies suggest that diffusion and reaction determines the chemical concentration around the growth fronts, which influences the growth of crystal structures, leading to the formation of diverse silver dendritic structures. The findings in this study indicate that chemical diffusion and reaction are two effective tools to regulate dendritic structures, promising a different way to promote or prevent the growth of dendritic structures in industries. (C) 2015 Elsevier Ltd. All rights reserved.

Calibration of a stereo vision system is essential for three-dimensional shape and deformation measurements. Although the target-based calibration technique is a good solution, it comes with limitations in a large field of view (FOV) measurement due to the target size and difficulties in operation. In this paper, a method using the inertial measurement unit (IMU) has been proposed to calibrate stereo vision systems for large-scale measurements. The prerequisite for this method is to calibrate the camera intrinsic parameters in advance. With the alignment of IMU sensor with the camera, the relative rotation between the two cameras can be determined through coordinate transform. An angular differential method has been developed to improve accuracy in determining the yaw angle. After the epipolar geometry is constructed upon stereo scene correspondences, the translation vector can be obtained by solving a set of linear equations, since the intrinsic parameters and the relative rotation are predefined. The proposed method does not require any known calibration target, leading to easy operation in practice. Two laboratory experiments are presented to demonstrate the use of the method. The experimental results show that the accuracy of the proposed method is comparable to that resulted from the well-known Zhang's method, and it can also be applied to measurement with a large FOV.

This paper proposes a methodology for the topology optimization of continuum structures subject to dynamic stress response constraints under stochastic loads. The topology optimization model is built, where the objective function is the structural weight, and the dynamic stress constraints are applied. In order to greatly reduce the computational cost of dynamic stress responses and prevent stress concentration phenomenon, the P-norm aggregation function is adopted to replace the dynamic stress response constraints. To solve the defined topology optimization problem, a method with varying dynamic stress response limit is presented, and the sensitivities of the equivalent dynamic stress response constraints with respect to the reciprocal design variables is derived so as to form the explicit approximate functions for structural equivalent dynamic stress response constraints. Then, based on dual theory, an algorithm by using nonlinear programming method with simple trust regions is introduced to solve the optimization problem. Finally, the results of several numerical examples are given to demonstrate the validity and effectiveness of the proposed approach.

Molecular dynamics simulation is a powerful tool in discovering nucleation phenomena. In a simulation of silver nucleation under a diffusion limited condition, the OPLS-AA force field is used to describe the glycerol solution. But the simulation crashes after running 260 ps. The energy and trajectories analyses indicate that the contact of the H and O atoms of the neighbor hydroxyls in the glycerol molecules leads to a sharp increase of the potential energy, which results in the crash of the simulation. We propose to introduce the repulsion force between the H and O atoms by modifying the Lennard-Jones parameters of these atoms in the original OPLS-AA force field. After the modification, the crashing problem is solved. Furthermore, the density and diffusion coefficient of glycerol simulated at the modified force field show better accuracy than that obtained by by AMBER and CHARMM force fields. With the one-step L-J modified OPLS force field, the silver nucleation is simulated. With the increase of glycerol, the size distribution of silver clusters switches from the multimodal to the unimodal.

More attention has been attracted to engineering structural design on fatigue failure, while few works are devoted to topology optimizations considering dynamic fatigue failure under random vibrations. In this paper, a new layout optimization method is proposed to consider high-cycle dynamic fatigue constraints which are caused by periodic random dynamic loads. Being incorporated with the rational approximation for material properties (RAMP), the optimization model is built, where the objective function is the structural weight, and the dynamic fatigue failure constraints are applied in the structure. According to the Crossland’s criterion, the dynamic fatigue constraints can be formulated by the peak value of the period fluctuating dynamic stress that never exceed the threshold. Then, the Kreisselmeier–Steinhauser (KS) aggregation function is introduced to reduce the number of dynamic fatigue failure constraints. To overcome stress concentration phenomenon, the P-norm aggregation function is introduced to the objective function as a penalty term. Moreover, a new penalty approach is introduced to solve stress singularity, and a constraint-limit-variant method is adopted to obtain stable convergent topologies. The sensitivity of the dynamic fatigue constraints with respect to the design variables is derived so as to form the approximate functions for the dynamic fatigue constraint functions and the objective function. Finally, based on the sensitivity and dual theory, the defined optimization problem is solved by the aforementioned algorithm. The results of several numerical examples are given to demonstrate the validity and effectiveness of the proposed approach.

Disorder of the sympathetic nervous system (SNS) is closely related to the pathogenesis of various autoimmune diseases (ADs). Catecholamine triggered beta2-adrenergic receptor (β2-AR) signaling is important in creating a bidirectional response in the progression of ADs due to factors including diverse expression patterns, single nucleotide polymorphisms (SNPs), biased signals, and desensitization of β2-AR, as well as different subtypes of Gα binding to β2-AR. In this review, we summarize the actions of β2-AR signaling in regulating the functions of immunocytes and in the pathogenesis of ADs, and the application of β2-AR agonists or antagonists in treating major types of ADs is also discussed. We suggest that restoring the immune balance via a soft regulation of the expression or activation of β2-AR is one of the promising therapeutic strategies for systematic ADs.

We provide an atomic decomposition of the product Hardy spaces $H^p(\widetilde{X})$ which were recently developed by Han, Li, and Ward in the setting of product spaces of homogeneous type $\widetilde{X} = X_1 \times X_2$. Here each factor $(X_i,d_i,\mu_i)$, for $i = 1$, $2$, is a space of homogeneous type in the sense of Coifman and Weiss. These Hardy spaces make use of the orthogonal wavelet bases of Auscher and Hyt\"onen and their underlying reference dyadic grids. However, no additional assumptions on the quasi-metric or on the doubling measure for each factor space are made. To carry out this program, we introduce product $(p,q)$-atoms on $\widetilde{X}$ and product atomic Hardy spaces $H^{p,q}_{{\rm at}}(\widetilde{X})$. As consequences of the atomic decomposition of $H^p(\widetilde{X})$, we show that for all $q > 1$ the product atomic Hardy spaces coincide with the product Hardy spaces, and we show that the product Hardy spaces are independent of the particular choices of both the wavelet bases and the reference dyadic grids. Likewise, the product Carleson measure spaces ${\rm CMO}^p(\widetilde{X})$, the bounded mean oscillation space ${\rm BMO}(\widetilde{X})$, and the vanishing mean oscillation space ${\rm VMO}(\widetilde{X})$, as defined by Han, Li, and Ward, are also independent of the particular choices of both wavelets and reference dyadic grids., Comment: Minor typos corrected, reference added. Submitted

The objective of this study was to compare the resistance to failure of three types of all-ceramic crowns under static and cyclic contact loading. Three types of crown specimens were fabricated (N = 14 per group) including: i) sintered bi-layer crowns (SBC) made of IPS e.max CAD veneers fused on Lava zirconia core ceramics, ii) adhesive bi-layer crowns (ABC) made of IPS e.max CAD veneers bonded onto Lava zirconia core ceramics, and iii) monolith ceramics crown (MCC) made of IPS e.max CAD. All were bonded onto a compliant substrate of resin composite with commercial adhesive. Eight specimens were selected from each group for monotonic loading to failure via 6 mm diameter ball to obtain the initial load capacity (Pinitial) of the crowns. The remaining six crown specimens were subjected to cyclic contact loading to 5 million cycles, and then loaded monotonically to fracture to obtain residual load capacity after fatigue (Presidual). A finite element analysis (FEA) was used to analyze the stress distributions within the three types of crowns and estimate the crack origins from the maximum stress. The initial load to failure (Pinitial) for the SBC, ABC, and MCC groups were 1120 ± 170 N, 970 ± 150 N, and 950 ± 60 N, respectively, and significantly different (p = 0.027). The residual load to failure after fatigue (Presidual) for the crown types were 890 ± 240 N, 680 ± 240 N, and 1050 ± 120 N, respectively, and also significantly different (p = 0.012). For SBC and MCC, failure occurred predominantly by bulk fracture, whereas the ABC failed primarily by chipping. The FEA suggested that failure of SBC and ABC would originate in the cement layers, and MCC has a more reasonable stress allocation than that in bi-layer crowns (SBC and ABC), which agreed with the observed failure modes. The SBC crowns had superior load to failure, whereas the bi-layer systems (SBC and ABC) had inferior fatigue resistance compared with the monolith crowns (MCC). The cement interface was the weak-link of the bi-layer systems, especially for ABC. Considering their use in clinical practice, the ranking in resistance to failure is SBC>MCC>ABC.

Silver particles, prepared in a T-mixer under different flow rates, were selected to study the influences of mixing on particle shape evolution. Mixing effects on particle growth were visualized by scanning electron microscopy (SEM) and analysed quantitatively by sedimentation coefficient distributions derived from analytical centrifugation (AC). The mixing time under different flow rates was determined by the Villermaux-Dushman method to quantify the mixing quality. Based on the finding of a mixing-induced shape transformation from plates to dendrites, an extended growth mechanism involving mixing effects was proposed. Slow mixing leads to a non-uniform distributed reactant mixture and low effective supersaturation. This causes preferential growth of high-energy facets resulting in plate-like particles with broad, multimodal sedimentation distributions. In contrast, fast mixing, corresponding to uniform reactant mixture and thus high effective supersaturation and nucleation rate, leads to dendritic products, and narrow but bimodal sedimentation distributions. (C) 2018 Elsevier Ltd. All rights reserved.

In this paper, we first show that the remarkable orthonormal wavelet expansion for L p constructed recently by Auscher and Hytonen also converges in certain spaces of test functions and distributions. Hence we establish the theory of product Hardy spaces on spaces X ˜ = X 1 × X 2 × ⋅ ⋅ ⋅ × X n , where each factor X i is a space of homogeneous type in the sense of Coifman and Weiss. The main tool we develop is the Littlewood–Paley theory on X ˜ , which in turn is a consequence of a corresponding theory on each factor space. We define the square function for this theory in terms of the wavelet coefficients. The Hardy space theory developed in this paper includes product H p , the dual CMO p of H p with the special case BMO = CMO 1 , and the predual VMO of H 1 . We also use the wavelet expansion to establish the Calderon–Zygmund decomposition for product H p , and deduce an interpolation theorem. We make no additional assumptions on the quasi-metric or the doubling measure for each factor space, and thus we extend to the full generality of product spaces of homogeneous type the aspects of both one-parameter and multiparameter theory involving the Littlewood–Paley theory and function spaces. Moreover, our methods would be expected to be a powerful tool for developing wavelet analysis on spaces of homogeneous type.

Material properties are strongly dependent on material structure. The large diversity and complexity of material structures provide significant opportunities to improve the properties of the materials, expanding their applications. Here, we discuss the fabrication of a multifunctional silver film prepared by controlling the nucleation and growth of silver particles. Silver films with high hydrophobicity and antibacterial activity were fabricated by adopting an electrochemical approach. The dependence of the hydrophobic and antibacterial properties on the size and shape of the silver particles was first investigated. Small-sized silver particles exhibited a high antibacterial rate, while a porous silver film composed of dendritic particles showed a significant hydrophobic activity. By regulating the reaction time, current density, and silver salt concentration, a silver film with a contact angle of 150.9 degrees and an antibacterial rate of 54.7% was synthesized. This study demonstrates that finding a compromise between different material structures is a suitable way to fabricate multifunctional devices.

Using nanoparticles as building blocks to build up hierarchical structures is the next big thing in nanoscience, as well as a core issue of the emerging mesoscience. The building process involves the movement of building blocks, followed by interaction and binding between them. The diffusion of building blocks is an important kinetic factor influencing the shape development of materials, but this issue has not yet been well investigated by the material research community. In this paper, we take the preparation of silver particles as an example to investigate how the diffusion of building blocks influences the shape of silver products. The silver products are prepared by reducing silver ions in a mixture of ethylene glycol and water. Through a change in the volume ratio of ethylene glycol in water, the diffusion of building blocks is tuned, which results in the formation of silver products with various shapes from rectangular plates to spindle rods. This shape variation is attributed to the change of the d...

The present study aimed to determine the molecular mechanisms leading to the production of advanced glycation end‑products (AGEs) and their effect on the morphology and function of rat glomerular capillary endothelial cells (GECs). Primary rat GECs were treated with AGE‑modified human serum albumin (AGE‑HSA) and divided into groups according to AGE concentration and treatment time. The structure and distribution of cytoskeletal protein F‑actin and the cortical actin binding protein, cortactin, were analyzed using immunofluorescence and confocal microscopy. As the Ras‑related C3 botulinum toxin substrate 1 (Rac1) signaling pathway was previously identified to be involved in mediating the contraction of endothelial actin‑myosin activity, Rac1 was examined subsequent to treatment of the cells with the Rac1 agonist 2'‑O‑methyladenosine‑3',5'‑cyclic monophosphate (O‑Me‑cAMP) for 1 h using a pull‑down assay. Cell permeability was determined by the leakage rate of a fluorescein isothiocyanate fluorescent marker protein. AGE‑HSA treatment resulted in alterations in the structure and distribution of F‑actin and cortactin in a dose‑ and time‑dependent manner, while no effect was observed with HSA alone. The effect of AGE on the cytoskeleton was inhibited by the addition of O‑Me‑cAMP. AGE‑HSA significantly reduced the level of Rac1 activity (P

Controllable synthesis of materials with designed structures is a long-term dream of scientists and engineers. The challenges faced by dreamers are the complexity of material formation and the diversity of material structures. One way to discover this complexity is to simplify the reaction system. Electrochemical reduction is one of the simple reaction systems in which electrons are used as the reductant to avoid the complexity of chemical effects. We design a two-cell electrochemical reactor. The cathode and the anode are placed in different cells connected by a salt bridge. Electrons are introduced into the cell containing silver ions. With this approach, silver particles are synthesized on the cathode. The reduction rate of silver ions is regulated by varying the current density over two orders of magnitude. At various current densities, silver particles with different morphologies are synthesized. The dependence of silver morphology on current density is ascribed to the influence of current density on the nucleation and growth of silver particles, which is confirmed by subsequent experiments. The results in this paper show that the electron is a simple and green reductant and the current density is an effective tool for regulating reaction rates to shape materials.

It has previously been demonstrated that Epigallocatechin gallate (EGCG) has regulatory effects on cellular immunity. The present study explored whether EGCG inhibits the overload‑induced cardiac extracellular matrix (ECM) remodeling through targeting the balance of T cell subpopulations. Sprague‑Dawley rats were subjected to either transverse aortic constriction (TAC) or sham operation. TAC rats were treated with EGCG or valsartan (Val) for 6 weeks. The administration of EGCG or Val ameliorated the overproduction of cardiac collagen, inhibited matrix metalloproteinase (MMP) activity, decreased the expression of tissue inhibitor of MMP‑2, atrial natriuretic peptide and brain natriuretic peptide. EGCG regulated the population of effector T cells and naive T cells, restored the balance of T helper (Th) cell 17/regulatory T cells, via modulating the downstream regulator signal transducer and activator of transcription (STAT3) and STAT5. Furthermore, the ratio of interferon‑γ/interleukin (IL)‑10 which indicates the balance of Th1/Th2, was restored by the treatments at varying degrees. EGCG and Val administration rescued IL‑7 production, and decreased the level of IL‑15 in TAC rats. EGCG has positive therapeutic potential in inhibiting cardiac ECM remodeling. Regulation of the balance of T lymphocyte subsets may be one of the underlying mechanisms responsible for this effect.

Skin cholesterol is a novel biomarker to assess the risk of atherosclerotic diseases. To detect skin cholesterol noninvasively and rapidly, a system was designed based on the diffuse reflectance spectroscopy. The feasibility of this system was validated through detecting cholesterol of pig skin samples, and skin cholesterol in vivo of subjects. The experimental results showed that, diffuse reflectance absorbance integrated intensity S measured the concentration of cholesterol in the pig skin samples quantitatively. After adjusting for age, gender and other factors, it showed a significant positive correlation between S of subjects and the total cholesterol (TC), low density lipoprotein cholesterol (LDL-C) which were the main risk factors for atherosclerotic diseases with the correlation coefficients 0.860(P

Sonication induces complex chemical and physical phenomena in solution, which attracted great attentions to discover the mechanisms behind these phenomena. One of these phenomena is the pH drop in sonication, which was usually attributed to the formation of nitrate and nitrite acid in sonication. However, the pH drop detected by electrodes was questioned since the sonication could enhance proton transfer on the surface of pH electrode, resulting in a false pH drop. Therefore, it is necessary to initiate a tour study on this issue. In this paper, we firstly investigate two new factors, namely CO2 dissolution and temperature, which have the possibility to induce the pH drop in sonication. The results demonstrate that both factors play a minor role on the pH drop. Then we employ pH sensitive dyes to replace the questioned pH electrode to detect the change of proton concentration in sonication. The results indicate that the pH drop is accompanied with the protonation of fluorescein, indicating production of hydrogen ions in sonication. The quantitative analysis of proton production suggests that the pH drop in sonication is mainly caused by the formation of hydrogen ions, which clarify the reason for the pH drop in sonication. (c) 2014 Elsevier B.V. All rights reserved.

Here we report a study on controlling the shape of particles by regulating the diffusion of chemicals. To change the diffusion rate of the reactive ions, we used a designed three-cell reactor in which the reactive ions were separated by porous membranes. We studied the reduction of hexachloroplatinate ions by sodium borohydride as an example. The experimental results show that control of the chemical diffusion led to the platinum product changing from cubic particles to dendritic particles. Further analysis indicates that the cubic particles were formed by the classic crystallization process via layer-wise deposition, while the dendritic particles were formed by the non-classic crystallization process through cluster aggregation. The control over the chemical diffusion prolongs the nucleation period and produces nuclei continuously, facilitating the aggregation of nuclei, which leads to the crystallization switching from the classic model to the non-classic model. The obtained results in this paper suggest that control over the chemical diffusion is a green and promising process to manipulate the structures of materials.

Material scientists have a strong interest in finding the reasons causing the diversity of material structures. Here, we show a different story in disclosing the mechanism dominating material structures. When we synthesize calcium carbonate particles at increased temperatures, we observe that the structures of the particles change with temperature. At a relatively low temperature (60 °C), dumbbell shaped particles are largely formed while straight particles are dominantly formed at a relatively high temperature (90 °C). By simulation, we find that the crystallite of aragonite is polarized after the adsorption of water molecules on its surface. The polarization is anisotropic, which makes the attachment of crystallites have different stabilities along different attaching directions. At an increased temperature, the attachment is easily destructed by Brownian motion which is dependent on temperature. Therefore, the adsorbing force provided by polarization competes with the destructive force induced by the Brownian motion. The compromise between these two competing forces dominates the stable structure of calcium carbonate particles. Hence, the compromise in competition between attractive forces and destructive forces leads to the diversity of aragonite structures, which indicates a new direction in discovering the diversity of material structures.

In this paper, we obtain the boundedness of singular integral operators T in Journe’s class on weighted multiparameter Hardy spaces \(H^{p}_{w}\) of arbitrary k number of parameters (k≥3) under the assumption that \(T^{\ast}_{i}(1)=0\), i=1,…,k, and the kernel of T has a regularity of order ϵ>0, where \(w \in A_{r}(\Bbb{R}^{n_{1}}\times \cdots \times \Bbb{R}^{n_{k}}), r \geq 1\) and \(\max\{ \frac{r n_{1} }{n_{1}+\varepsilon}, \ldots, \frac{r n_{k} }{n_{k}+\varepsilon}\}

Wilson's disease (WD) causes deposition of copper, mainly in the basal ganglia. One consequence of deposition seems to be impairment of executive functions, which could cause problems in decision making. In 30 WD patients and 30 healthy controls (HCs), we examined decision making under risk in the Game of Dice Task, and we assessed working memory and executive functions. WD patients exhibited a greater preference for disadvantageous choices than did HCs. Reduced decision-making performance was closely correlated to lower executive functions. Decision-making deficits of WD might be associated with frontostriatal loops, which are involved in executive functions and feedback processing.

Protein microcapsules with narrow size distribution have been prepared by sonochemical method which is a simple, fast, environmental friendly and cost-effective method. The prepared microcapsules are composed of a water-insoluble core and an outer protein shell. The hydrophobic drugs could be encapsulated into protein microcapsules directly via sonochemical method by dissolving drugs in the nontoxic and edible vegetable oil before ultrasonication, which is a potential solution for drug resistance by hiding cytotoxic drugs in the carrier and allows for the delivery of high doses in relatively small volume. The size and size distribution of protein microcapsules are very important for their practical application. In this paper, the factors affecting the size and size distribution of protein microcapsules are investigated in detail. Moreover, confocal laser scanning microscopy and transmission electron microscopy confirmed that the protein microcapsules with narrow size distribution were obtained.

The diffusion and reaction are two general kinetic factors playing an important role in the structure development of materials. Upon diffusion limitation, a noncompact structure is easily formed, while a compact structure is usually formed in, a reaction-limited condition. In this Article, we take the precipitation of calcium carbonate as an example to discover the roles of diffusion and reaction in shaping particles. By adjusting the diffusion and reaction in a three-cell reactor, we synthesize snow-shaped particles, which are a new morphology of calcium carbonate. The microscopic characterization shows that the microparticle is composed of aggregates of nanoparticles. Computer simulation suggests that the snow-shaped particle is formed in a condition that the diffusion and reaction compete to regulate the structure of particles and their compromise leads to the formation of snow-shaped morphology, which is confirmed by later experiments. The following discussion concentrates on the compromise concept to disclose its essence and role in shaping particles, which brings us a new view on the physical mechanisms governing the diversity of materials structures.

This article concerns nonconvolutional type operators (also known as Journeʼs type operators) associated with a multiparameter family of dilations given by ( x 1 , x 2 , … , x m ) → ( δ 1 x 1 , δ 2 x 2 , … , δ m x m ) where x 1 ∈ R n 1 , x 2 ∈ R n 2 , … , x m ∈ R n m and m ⩾ 3 . We are especially interested in the boundedness of such operators on the multiparameter Hardy spaces. This work is motivated by Pipherʼs result on the boundedness of these operators from the multiparameter H p spaces to L p spaces for 0 p ⩽ 1 , and Journeʼs counter-example which shows that the number of parameter plays a crucial role in boundedness of singular integral operators on multiparameter Hardy spaces. Journeʼs work shows that there is a sharp difference between the situations for two and three or more parameters. We establish in this paper the necessary and sufficient conditions under which the singular integral operators in Journeʼs class are bounded on multiparameter H p spaces ( 0 p ⩽ 1 ) with arbitrary number of parameters.

It is well known that standard Calderon-Zygmund singular integral operators with the isotropic and non-isotropic homogeneities are bounded on the classical H(R) and non-isotropic H h(R ), respectively. In this paper, we develop a new Hardy space theory and prove that the composition of two Calderon-Zygmund singular integral operators with different homogeneities is bounded on this new Hardy space. It is interesting that such a Hardy space has surprisingly a multiparameter structure associated with the underlying mixed homogeneities arising from two singular integral operators under consideration. The Calderon-Zygmund decomposition and an interpolation theorem hold on such new Hardy spaces.

The Marcinkiewicz multipliers are $L^{p}$ bounded for $1 on the Heisenberg group $\mathbb{H}^{n}\simeq \mathbb{C}^{n}\times \mathbb{R}$ (Müller, Ricci, and Stein). This is surprising in the sense that these multipliers are invariant under a two parameter group of dilations on $\mathbb{C}^{n}\times \mathbb{R}$ , while there is no two parameter group of automorphic dilations on $\mathbb{H}^{n}$ . The purpose of this paper is to establish a theory of the flag Lipschitz space on the Heisenberg group $\mathbb{H}^{n}\simeq \mathbb{C}^{n}\times \mathbb{R}$ that is, in a sense, intermediate between that of the classical Lipschitz space on the Heisenberg group $\mathbb{H}^{n}$ and the product Lipschitz space on $\mathbb{C}^{n}\times \mathbb{R}$ . We characterize this flag Lipschitz space via the Littlewood–Paley theory and prove that flag singular integral operators, which include the Marcinkiewicz multipliers, are bounded on these flag Lipschitz spaces.

This paper is inspired by the work of Nagel and Stein in which the L p L^p ( 1 > p > ∞ ) (1>p>\infty ) theory has been developed in the setting of the product Carnot-Carathéodory spaces M ~ = M 1 × ⋯ × M n \widetilde {M}=M_1\times \cdots \times M_n formed by vector fields satisfying Hörmander’s finite rank condition. The main purpose of this paper is to provide a unified approach to develop the multiparameter Hardy space theory on product spaces of homogeneous type. This theory includes the product Hardy space, its dual, the product B M O BMO space, the boundedness of singular integral operators and Calderón-Zygmund decomposition and interpolation of operators. As a consequence, we obtain the endpoint estimates for those singular integral operators considered by Nagel and Stein (2004). In fact, we will develop most of our theory in the framework of product spaces of homogeneous type which only satisfy the doubling condition and some regularity assumption on the metric. All of our results are established by introducing certain Banach spaces of test functions and distributions, developing discrete Calderón identity and discrete Littlewood-Paley-Stein theory. Our methods do not rely on the Journé-type covering lemma which was the main tool to prove the boundedness of singular integrals on the classical product Hardy spaces.

The aim of the study was to perform a meta-analysis of the efficacy and safety of (bortezomib plus lenalidomide/thalidomide)- vs (bortezomib or lenalidomide/thalidomide)-containing regimens as induction therapy in newly diagnosed multiple myeloma. We searched electronic and printed sources for relevant articles published. Inclusion criteria was as follows: randomized controlled trials (RCT) of (bortezomib plus lenalidomide/thalidomide) vs (bortezomib or lenalidomide/thalidomide)-containing regimens as induction therapy in newly diagnosed multiple myeloma. Two reviewers independently assessed potentially eligible studies and extracted relevant data. We retrieved five RCT studies including a total of 1,200 patients. Using the random-effects model to pool the five RCT with a statistically significant heterogeneity (P = 0.03; X2 = 10.69; df = 4; I2 = 63 %), the weighted risk ratios of a complete response (CR) for (bortezomib plus lenalidomide/thalidomide)-containing regimens was 1.81 (P = 0.005; 95 % CI: 1.20–2.73). When we excluded the study by Cavo et al. (Lancet 376:2075–2085, 2010), the pooled risk ratio for CR was 1.59 (P < 0.0001, 95 %CI: 1.29–1.96) with no statistically significant heterogeneity (P = 0.54; X2 = 2.14; df = 3; I2 = 0 %) among four RCT under the fixed effects mode. The pooled odds ratio for the main grade III/IV adverse events (the peripheral neuropathy, thrombotic events, and infections) were 1.76 (P = 0.32; 95 % CI: 0.58–5.31), 0.92 (P = 0.76, 95 %CI: 0.52–1.61), and 1.05 (P = 0.82, 95 % CI: 0.70–1.57), respectively. Our analysis showed (bortezomib plus lenalidomide/thalidomide)-containing regimens as induction treatment in newly diagnosed multiple myeloma improved CR but did not increase the risk of major adverse events (the peripheral neuropathy, thrombotic events, and infections).

In this article, we establish a new atomic decomposition for , where the decomposition converges in -norm rather than in the distribution sense. As applications of this decomposition, assuming that T is a linear operator bounded on and 0 < p ≤ 1, we obtain (i) if T is uniformly bounded in -norm for all w-p-atoms, then T can be extended to be bounded from to ; (ii) if T is uniformly bounded in -norm for all w-p-atoms, then T can be extended to be bounded on ; (iii) if T is bounded on , then T can be extended to be bounded from to .

Photoanodes for flexible DSSC have been prepared through a chemical sintering method using hydrothermal cement at low temperature of 120 degrees C. The addition of the hydrothermal cement can effectively increase the adhesion between the photoanode and flexible ITO-PET substrate and build the interconnection between nanoparticles at low temperature for the fast transport of electrons. The flexible DSSC based on the photoanode obtains a relatively high photo-to-electric conversion efficiency of 4.0%. The method basing on the commercially available TiO2 with a small proportion of hydrothermal cement is suitable for roll-to-roll screen-printing preparation, which is expected to be scaled up for mass production of high performance flexible DSSCs.

In this paper, we study the structure of the Hardy space \({H^p_b}\) associated with a para-accretive function b, which was introduced in Han et al. (J. Geom. Anal. 14:291–318, 2004). The main result is to establish a new atomic decomposition of \({H^p_b}\) . As applications, we obtain criterions for the boundedness of operators on \({H^p_b}\) and a characterization of the dual space of \({H^p_b}\) . The classification of \({H^p_b}\) and Calderon–Zygmund decomposition are also discussed.

With the dramatic development of computational science and technology, computer simulation is playing an increasingly important role in scientific research and engineering practice, and is believed to bring about a profound revolution to the mode and means of these activities. For chemical engineering, it will promote the transition from an experience-and-experiment-based research and development mode to the one based on virtual process engineering (VPE). However, such a revolutions till requires tremendous improvements in the Accuracy of physical modeling and numerical methods, the Capability of the computing hardware and software, and the Efficiency of the simulation activities, or in short, ACE. This article will systematically review the 3-decade endeavors at IPE, CAS(Institute of Process Engineering, Chinese Academy of Sciences) on upgrading ACE by establishing a multi-scale computing paradigm focusing on meso-scale structures. We also report recent developments in this direction with projections on future work.

We apply the discrete version of Calderon’s identity and Littlewood–Paley–Stein theory with weights to derive the \((H^p_w, H^p_w)\) and \((H^p_w, L^p_w) (0 1 for w ∈ Ap to the case of weighted Hardy spaces \(H^p_w\) for p ≤ 1, but under a weaker assumption that w belongs to the class of product A ∞ weights with respect to rectangles in product spaces.

In this paper, we introduce the Carleson measure space CMO p on product spaces of homogeneous type in the sense of Coifman and Weiss (4), and prove that it is the dual space of the product Hardy space H p of two homogeneous spaces defined in (15). Our results thus extend the duality theory of Chang and R. Fefferman (2, 3) on H 1 (R 2 × R 2 ) with BMO(R 2 × R 2 ) which was estab- lished using bi-Hilbert transform. Our method is to use discrete Littlewood-Paley analysis in product spaces recently developed in (13) and (14).

In crystallization, nanoparticle aggregation often leads to the formation of orderly structures, even single crystals. Why can nanoparticles form orderly structures and what is the mechanism dominating their orderly aggregation? These questions raise interesting research problems, but the occurrences that could answer them often fail to be directly observed, since the interaction among particles is invisible. Here, we report an attempt to discover the interaction and aggregation of building blocks through a computer simulation, focusing on the shape effect of building blocks on the aggregation. Four types of silver building blocks were selected, each consisting of (100) and (111) facets, but the ratio of these two facets was different. It was found that the area of facets played an important role in selecting the aggregation mode. The facets with a large area and high energy had a high possibility of aggregation. In addition, the effects of solvent viscosity and temperature were also investigated. High viscosity and low temperature enhanced the orderliness of aggregation. This paper reports a detailed view of the aggregation process of silver nanoparticles, which is expected to be helpful in understanding the structure evolution of materials in nonclassical crystallization.

We designed a biocompatible carrier for controlled release of hydrophobic drugs. The designed carrier was prepared by sonicating oil in a protein aqueous solution forming a protein nanocontainer composed of an inner gel core and an outer protein shell. Two model drugs were loaded into the designed nanocontainers by dissolving drugs in the oil phase before sonication. The loading capacity was up to 0.9 mg/mL for the amphiphilic drug rifampicin, while it reached to 19 mg/mL for the hydrophobic drug indomethacin. The encapsulated drugs were released at different temperatures. At 37 degrees C, only less than 20% of the drug was released due to the protection by the gel core. Increasing temperature to 40 degrees C led to a completely release of the remaining drug. The drug release showed drastic temperature dependence. The biocompatibility of the protein nanocontainers was evaluated by incubating the nanocontainers in the 3T3 cell and B-LCL cell lines. Both experiments indicated an excellent biocompatibility of the designed nanocontainers.

Let T be a product Calderón–Zygmund singular integral introduced by Journé. Using an elegant rectangle atomic decomposition of Hp(Rn×Rm) and Journé's geometric covering lemma, R. Fefferman proved the remarkable Hp(Rn×Rm)−Lp(Rn×Rm) boundedness of T. In this paper we apply vector-valued singular integral, Calderón's identity, Littlewood–Paley theory and the almost orthogonality together with Fefferman's rectangle atomic decomposition and Journé's covering lemma to show that T is bounded on product Hp(Rn×Rm) for max{nn+ε,mm+ε}

Photoelasticity is an effective method for evaluating the stress and its spatial variations within a stressed body. In the present study, a method to determine the stress distribution by means of phase shifting and a modified shear-difference is proposed. First, the orientation of the first principal stress and the retardation between the principal stresses are determined in the full-field through phase shifting. Then, through bicubic interpolation and derivation of a modified shear-difference method, the internal stress is calculated from the point with a free boundary along its normal direction. A method to reduce integration error in the shear difference scheme is proposed and compared to the existing methods; the integration error is reduced when using theoretical photoelastic parameters to calculate the stress component with the same points. Results show that when the value of Δx/Δy approaches one, the error is minimum, and although the interpolation error is inevitable, it has limited influence on the accuracy of the result. Finally, examples are presented for determining the stresses in a circular plate and ring subjected to diametric loading. Results show that the proposed approach provides a complete solution for determining the full-field stresses in photoelastic models.

In biological system, early detection and treatment at the same moment is highly required. For synthetic materials, it is demanding to develop materials that possess self-reporting of early damage and self-healing simultaneously. This dual function is achieved in this work by introducing an intelligent pH-responsive coatings based on poly(divinylbenzene)-graft-poly(divinylbenzene-co-methacrylic acid) (PDVB-graft-P(DVB-co-AA)) core-shell microspheres as smart components of the polymer coatings for corrosion protection. The key component, synthesized PDVB-graft-P(DVB-co-AA) core-shell microspheres are porous and pH responsive. The porosity allows for encapsulation of the corrosion inhibitor of benzotriazole and the fluorescent probe, coumarin. Both loading capacities can be up to about 15 wt%. The polymeric coatings doped with the synthesized microspheres can adapt immediately to the varied variation in pH value from the electrochemical corrosion reaction and release active molecules on demand onto the damaged cracks of the coatings on metal surfaces. It leads simultaneously to the dual functions of self-healing and self-reporting. The corrosion area can be self-reported in 6 h, while the substrate can be protected at least for 1 month in 3.5 wt% NaCl solution. These pH-responsive materials with self-reporting and self-healing dual functions are highly expected to have a bright future due to their smart, long-lasting, recyclable, and multifunctional properties.

Hollow CaCO3 particles were synthesized by passing CO2/N2 bubbles into a CaCl2 solution. The formation of such hollow particles was investigated via the nucleation mechanism of calcium carbonate. It was found that homogeneous and heterogeneous nucleation both occurred via a three phase gas−liquid−solid reaction. However, only the latter played a role in the formation of the described hollow particles. Nuclei were initially formed at the bubble surface and subsequently aggregated together to form the initial shell. Growth of the initial shell structure proceeded along the bubble surface by the subsequent aggregation of nuclei. Concurrently it was found that the combination of reaction ions, Ca2+ and CO32−, adsorbed on the outer surface of the growing shell resulted in the increase of shell thickness in a direction perpendicular to the bubble template surface. Both aggregation of nuclei and crystal growth contributed to the formation of the shell structure, with distinguishable inner and outer layers presen...

We present a construction of anisotropic multiresolution and anisotropic wavelet frames based on multilevel ellipsoid covers (dilations) of ℝn. The wavelets we construct are C∞ functions, can have any prescribed number of vanishing moments and fast decay with respect to the anisotropic quasi-distance induced by the cover. The dual wavelets are also C∞, with the same number of vanishing moments, but with only mild decay with respect to the quasi-distance. An alternative construction yields a meshless frame whose elements do not have vanishing moments, but do have fast anisotropic decay.