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Reproduction involves the investment of resources into offspring. Although variation in reproductive effort often affects the number of offspring, adjustments of propagule size are also found in numerous species, including the Western honey bee, Apis mellifera. However, the proximate causes of these adjustments are insufficiently understood, especially in oviparous species with complex social organization in which adaptive evolution is shaped by kin selection. Here, we show in a series of experiments that queens predictably and reversibly increase egg size in small colonies and decrease egg size in large colonies, while their ovary size changes in the opposite direction. Additional results suggest that these effects cannot be solely explained by egg-laying rate and are due to the queens' perception of colony size. Egg-size plasticity is associated with quantitative changes of 290 ovarian proteins, most of which relate to energy metabolism, protein transport, and cytoskeleton. Based on functional and network analyses, we further study the small GTPase Rho1 as a candidate regulator of egg size. Spatio-temporal expression analysis via RNAscope and qPCR supports an important role of Rho1 in egg-size determination, and subsequent RNAi-mediated gene knockdown confirmed that Rho1 has a major effect on egg size in honey bees. These results elucidate how the social environment of the honey bee colony may be translated into a specific cellular process to adjust maternal investment into eggs. It remains to be studied how widespread this mechanism is and whether it has consequences for population dynamics and epigenetic influences on offspring phenotype in honey bees and other species. [ABSTRACT FROM AUTHOR]

Numerically solving the 2D Helmholtz equation is widely known to be very difficult largely due to its highly oscillatory solution, which brings about the pollution effect. A very fine mesh size is necessary to deal with a large wavenumber leading to a severely ill-conditioned huge coefficient matrix. To understand and tackle such challenges, it is crucial to analyze how the solution of the 2D Helmholtz equation depends on (perturbed) boundary and source data for large wavenumbers. In fact, this stability analysis is critical in the error analysis and development of effective numerical schemes. Therefore, in this paper, we analyze and derive several new sharp wavenumber-explicit stability bounds for the 2D Helmholtz equation with inhomogeneous mixed boundary conditions: Dirichlet, Neumann, and impedance. We use Fourier techniques, Rellich's identity, and a lifting strategy to establish these stability bounds. Some examples are given to show the optimality of our derived wavenumber-explicit stability bounds. [ABSTRACT FROM AUTHOR]

We consider a sequence of four variable polynomials by refining Stieltjes's continued fraction for Eulerian polynomials. Using combinatorial theory of Jacobi-type continued fractions and bijections, we derive various combinatorial interpretations in terms of permutation statistics for these polynomials, which include special kinds of descents and excedances in a recent paper of Baril and Kirgizov. As a byproduct, we derive several equidistribution results for permutation statistics, which enables us to confirm and strengthen a recent conjecture of Vajnovszki and also to obtain several companion permutation statistics for two bistatistics in a conjecture of Baril and Kirgizov. [ABSTRACT FROM AUTHOR]

Behavioral specialization is key to the success of social insects and leads to division of labor among colony members. Response thresholds to task-specific stimuli are thought to proximally regulate behavioral specialization, but their neurobiological regulation is complex and not well understood. Here, we show that response thresholds to task-relevant stimuli correspond to the specialization of three behavioral phenotypes of honeybee workers in the well-studied and important Apis mellifera and Apis cerana. Quantitative neuropeptidome comparisons suggest two tachykinin-related peptides (TRP2 and TRP3) as candidates for the modification of these response thresholds. Based on our characterization of their receptor binding and downstream signaling, we confirm a functional role of tachykinin signaling in regulating specific responsiveness of honeybee workers: TRP2 injection and RNAi-mediated downregulation cause consistent, opposite effects on responsiveness to task-specific stimuli of each behaviorally specialized phenotype but not to stimuli that are unrelated to their tasks. Thus, our study demonstrates that TRP signaling regulates the degree of task-specific responsiveness of specialized honeybee workers and may control the context specificity of behavior in animals more generally. [ABSTRACT FROM AUTHOR]

This article proposes a three-stage dead-time adjustment scheme for the leading-leg and lagging-leg switches of phase-shift full-bridge converter (PSFBC) according to the load conditions to enhance the conversion efficiencies at light loads. This article also investigates an iterative rigorous loss calculation for light loads under dead-time adjustment. The proposed iterative calculation can be used to modify the duty ratio of the transition region and estimate the operating currents more accurately; therefore, the losses of a PSFBC at light loads and under the dead-time adjustments can be effectively estimated. A PSFBC prototype with an input voltage of 380 V, an output voltage of 48 V, and a rated output power of 480 W is designed and implemented in this article. Experimental results show that comparing with the PSFBC without the dead-time adjustment and with the conventional dead-time adjustment, the conversion efficiency enhancements of 12.13% and 5.97% can be achieved by the proposed three-stage dead-time adjustment scheme at about 5% load condition, respectively. For a small-scale data center with 100 designed PSFBCs, simulated results indicate that about 3.21 MWh of electricity and 1.03 tons of carbon dioxide emission can be saved and reduced per year, respectively, by the proposed dead-time adjustment scheme. [ABSTRACT FROM AUTHOR]

In this paper, we focus on the well-posedness problem of the threedimensional incompressible viscous and resistive Hall-magnetohydrodynamics system (Hall-MHD) with variable density. We mainly prove the existence and uniqueness issues of the density-dependent incompressible Hall-magnetohydrodynamic system in critical spaces on R3. [ABSTRACT FROM AUTHOR]

The energy adsorption properties of all-metallic corrugated sandwich cylindrical shells (CSCSs) subjected to axial compression loading were investigated by the method combining experiments, finite element (FE) simulations, and theoretical analysis. CSCS specimens manufactured using two different methods, i.e., high-speed wire-cut electric discharge machining (HSWEDM) and extrusion, were tested under axial compression. While specimens fabricated separately by HSWEDM and extrusion both exhibited a stable crushing behavior, the extruded ones were much more applicable as lightweight energy absorbers because of their good energy absorption capacity, repeatability, and low cost. The numerically simulated force-displacement curve and the corresponding deformation morphologies of the CSCS compared well with those obtained from experiments. The specific folding deformation mode was revealed from both experiments and simulations. Subsequently, based upon the mode of folding deformation, a theoretical model was established to predict the mean crushing force of the CSCS construction. It was demonstrated that CSCSs with more corrugated units, smaller value of tc/tf and W/Ro could dissipate more impact energy. Such sandwich cylindrical shells exhibited better energy absorption than monolithic cylindrical shells, with an increase of at least 30%. Ultimately, the dynamic effect under the impact load was further evaluated. The dynamic amplification coefficient of CSCS decreased with the increase of the wall thickness. [ABSTRACT FROM AUTHOR]

Objective: This study aimed to identify proteins related to paclitaxel and carboplatin chemoresistance in cervical cancer. Methods: Quantitative proteomic analysis was performed on normal SiHa cells and those treated with paclitaxel and carboplatin for 14 days, with isobaric tags for relative and absolute quantitation (iTRAQ) analysis. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were used to identify related processes and differentially expressed proteins. Results: A total of 67 and 96 differentially expressed proteins were identified in the paclitaxel- and carboplatin- treated groups, respectively. GO and KEGG enrichment analyses identified 53 (43 upregulated and 10 downregulated) and 85 differentially expressed proteins (70 upregulated and 15 downregulated) in the paclitaxel- and carboplatin-treated groups, respectively. The cell counting kit-8 results revealed that APOA1 was overexpressed in both the paclitaxel- and carboplatin- resistant SiHa cells compared with the control cells. Immunohistochemistry showed that APOA1 was highly expressed in the paclitaxel- and carboplatin- resistant squamous cell carcinoma of the cervix. Conclusion: This study is the first to use iTRAQ to identify paclitaxel- and carboplatinresistance proteins in cervical cells. We identified several proteins previously unassociated with paclitaxel and carboplatin resistance in cervical cancer, thereby expanding our understanding of paclitaxel and carboplatin resistance mechanisms. Moreover, these findings indicate that the APOA1 protein could serve as a potential marker for monitoring and predicting paclitaxel and carboplatin resistance levels. [ABSTRACT FROM AUTHOR]

Reactive oxygen species (ROS) generation and mitochondrial dysfunction are related to neuron loss in multiple sclerosis (MS). Although peroxisome proliferator-activated receptor-γ coactivator 1α (PGC-1α) appears to play a key role in modulating levels of mitochondrial ROS, antioxidants, and uncoupling proteins (UCPs), and PGC-1α expression is reduced in the neocortex of patients with MS, it is unclear what its role is in neurons and in the manifestation of clinical symptoms of MS. Here, we show in wild-type (WT) experimental autoimmune encephalomyelitis (EAE) mice that PGC-1α is decreased 13 d after EAE induction followed by a steady decline up to 20 d. These changes were accompanied by parallel alterations in levels of superoxide dismutase 2, peroxiredoxin 3, thioredoxin 2, UCP4, and UCP5. In transgenic (TG) mice with neuron-specific overexpression of PGC-1α (PGC-1αf/fEno2-Cre), clinical symptoms after EAE induction were delayed and less severe than in WT mice. The degrees of apoptotic neuron loss and demyelination were also less severe in PGC-1α-TG mice. Overexpression of PGC-1α in neuronal neuroblastoma spinal cord 34 cells subjected to EAE inflammatory conditions showed similar results to those obtained in vivo. RNA sequencing analysis showed that apoptotic processes were significantly enriched in the top 10 significant gene ontology (GO) terms of differentially expressed genes, and the apoptotic pathway was significantly enriched in Kyoto Encyclopedia of Genes and Genomes pathway analysis. Our findings indicate that up-regulation of neuronal PGC-1α protected neurons from apoptosis in EAE. Manipulating PGC-1α levels in MS may help stave off this devastating disease. [ABSTRACT FROM AUTHOR]

A boryl radical-triggered C-H functionalization of aliphatic ethers/amines or DMF with isocyanides is developed to deliver diverse phenanthridine derivatives in good to excellent yields. The substrate scope is broad, and a wide range of functional groups are tolerated under the standard conditions. The rapid removal of HBPin species by 4-cyanopyridine 1-oxide provides the driving force for this reaction. This new method should make boryl radicals widely applicable in organic synthesis. [ABSTRACT FROM AUTHOR]

In [5], Chemin, Gallagher and Paicu proved the global regularity of solutions to the classical Navier-Stokes equations with a class of large initial data on T2 × R. This data varies slowly in vertical variable and has a norm which blows up as the small parameter ( represented by ∈ in the paper) tends to zero. However, to the best of our knowledge, the result is still unclear for the whole spaces R3. In this paper, we consider the generalized Navier-Stokes equations on Rn(n ≥ 3): ∂tu + u • Δu + Dsu + ΔP = 0, div u = 0. For some suitable number s, we prove that the Cauchy problem with initial data of the form u0∈(x) = (v0h(x∈), ∈1v0n (x∈))T , x∈ = (xh, ∈xn)T , is globally well-posed for all small ∈ > 0, provided that the initial velocity profile v0 is analytic in x0 and certain norm of v0 is suffciently small but independent of ∈. In particular, our result is true for the n-dimensional classical Navier-Stokes equations with n ≥ 4 and the fractional Navier-Stokes equations with 1 ≤ s < 2 in 3D. [ABSTRACT FROM AUTHOR]

In this paper, we propose an approach to construct a family of two-dimensional compactly supported real-valued quincunx tight framelets {φ; ψ1, ψ2, ψ3} in L2(ℝ2) with symmetry property and arbitrarily high orders of vanishing moments. Such quincunx tight framelets are associated with quincunx tight framelet filter banks {a; b1, b2, b3} having increasing orders of vanishing moments, possessing symmetry property, and enjoying the additional double canonical properties: b1(k1, k2) = (-1)1+k1+k2a(1 - k1,-k2), b3(k1, k2) = (-1)1+k1+k2 b2(1 - k1,-k2), ∀ k1, k2 ∈ ℤ. Moreover, the supports of all the high-pass filters b1, b2, b3 are no larger than that of the low-pass filter a. For a low-pass filter a which is not a quincunx orthogonal wavelet filter, we show that a quincunx tight framelet filter bank {a; b1, …, bL} with b1 taking the above canonical form must have L ≥ 3 highpass filters. Thus, our family of double canonical quincunx tight framelets with symmetry property has the minimum number of generators. Numerical calculation indicates that this family of double canonical quincunx tight framelets with symmetry property can be arbitrarily smooth. Using one-dimensional filters having linear-phase moments, in this paper we also provide a second approach to construct multiple canonical quincunx tight framelets with symmetry property. In particular, the second approach yields a family of 6-multiple canonical real-valued quincunx tight framelets in L2(ℝ2) and a family of double canonical complex-valued quincunx tight framelets in L2(ℝ2) such that both of them have symmetry property and arbitrarily increasing orders of smoothness and vanishing moments. Several examples are provided to illustrate our general construction and theoretical results on canonical quincunx tight framelets in L2(ℝ2) with symmetry property, high vanishing moments, and smoothness. Quincunx tight framelets with symmetry property constructed by both approaches in this paper are of particular interest for their applications in computer graphics and image processing due to their polynomial preserving property, full symmetry property, short support, and high smoothness and vanishing moments. [ABSTRACT FROM AUTHOR]

Pseudotsuga sinensis, a vulnerable relict coniferous tree species, faces threats from overexploitation and habitat loss. Despite its status, the forest types, community structure, and population characteristics of this species in China have remained largely unknown. In our study, we conducted analyses of 69 vegetation plots where P. sinensis was the dominant species in southwestern China. We identified five forest types, i.e., Type 1: Pseudotsuga sinensis evergreen coniferous forest; Type 2: Pseudotsuga sinensis - Pinus yunnanensis evergreen coniferous forest; Type 3: Pseudotsuga sinensis - Cyclobalanopsis glaucoides evergreen coniferous and broad-leaved mixed forest; Type 4: Pseudotsuga sinensis - Platycarya strobilacea evergreen coniferous and deciduous broad-leaved mixed forest; Type 5: Pseudotsuga sinensis - Calocedrus macrolepis evergreen coniferous forest. These forests exhibited a multilayered vertical structure. The Simpson diversity index ranged between 0.58-0.86, while the Shannon-Wiener diversity index ranged from 1.24 to 2.3. P. sinensis trees' average growth rate of ring width decreased from 5.86 to 0.33 mm/year as increasing ages. Observed maximum age of P. sinensis was 115 years with 78 cm diameter at the breast height. Age frequency distribution of P. sinensis was multimodal. There was a great lack of individuals at 0-20 years old. Forests with moderate disturbance showed a significantly higher number of P. sinensis individuals younger than 30 years compared to areas with no, slight, or severe disturbance. P. sinensis' regeneration depends on moderate disturbance. We recommended delineating buffer zones in the protected areas at certain sites and in such zones can be allowed to sustainable firewood cutting by selectively marked species other than P. sinensis. [ABSTRACT FROM AUTHOR]

A convenient and efficient method for the construction of aryl trifluoromethyl selenoethers from the corresponding aryl halides in the presence of Ni(COD)2 and an appropriate ligand is reported. Various aryl iodides, bromides, and chlorides were smoothly converted in this reaction by simply varying the ligand, which afforded aryl and heteroaryl trifluoromethyl selenoethers in good to almost quantitative yields. The reaction was also applicable to the synthesis of druglike molecules. This work is the first report for trifluoromethylselenolation of aryl chlorides. Advantages of the present Ni-catalyzed approach include mild reaction conditions, good functional group tolerance, inexpensive reagents, easy operation, and no use of additional additives. This protocol allows for a straightforward and reliable access to trifluoromethyl selenides that are latent screening candidates for new pharmaceuticals and agrochemicals. [ABSTRACT FROM AUTHOR]

Endoglycoceramidases (EGCases) specifically hydrolyze the glycosidic linkage between the oligosaccharide and the ceramide moieties of various glycosphingolipids, and they have received substantial attention in the emerging field of glycosphingolipidology. However, the mechanism regulating the strict substrate specificity of these GH5 glycosidases has not been identified. In this study, we report a novel EGCase I from Rhodococcus equi 103S (103S_EGCase I) with remarkably broad substrate specificity. Based on phylogenetic analyses, the enzyme may represent a new subfamily of GH5 glycosidases. The X-ray crystal structures of 103S_EGCase I alone and in complex with its substrates monosialodihexosylganglioside (GM3) and monosialotetrahexosylganglioside (GM1) enabled us to identify several structural features that may account for its broad specificity. Compared with EGCase II from Rhodococcus sp. M-777 (M777_EGCase II), which possesses strict substrate specificity, 103S_EGCase I possesses a longer α7-helix and a shorter loop 4, which forms a larger substrate-binding pocket that could accommodate more extended oligosaccharides. In addition, loop 2 and loop 8 of the enzyme adopt a more open conformation, which also enlarges the oligosaccharide-binding cavity. Based on this knowledge, a rationally designed experiment was performed to examine the substrate specificity of EGCase II. The truncation of loop 4 in M777_EGCase II increased its activity toward GM1 (163%). Remarkably, the S63G mutant of M777_EGCase II showed a broader substrate spectra and significantly increased activity toward bulky substrates (up to>1370-fold for fucosyl-GM1). Collectively, the results presented here reveal the exquisite substrate recognitionmechanismofEGCasesandprovideanopportunity for further engineering of these enzymes. [ABSTRACT FROM AUTHOR]

Background: Non-neuronal acetylcholine (ACh) restricts autoimmune responses and attenuates inflammation by cholinergic anti-inflammation pathway. To date, the implication of ACh in myasthenia gravis (MG) remained unexplored. This study aimed to investigate the possible relationship between ACh levels, anti-muscle-specific tyrosine kinase (MuSK) antibody titers, main clinical features and outcomes of MG patients.Methods: We successfully measured ACh levels in human peripheral blood mononuclear cells (PBMCs) from 125 MG patients and 50 matched healthy controls by using ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). We assessed the quantitative MG (QMG) scores for each patient and titered anti-MuSK antibody.Results: We found that PBMC-derived ACh level was significantly higher in MG patients, especially in patients of class III, IV-V, compared with that in controls (0.142 ± 0.108 vs. 0.075 ± 0.014 ng/million cells, p = 0.0003) according to the Myasthenia Gravis Foundation of America clinical classification. Importantly, we also found that ACh levels were positively correlated with QMG scores (r = 0.83, p < 0.0001) and anti-MuSK Ab levels (r = 0.85, p < 0.0001).Conclusions: Our demonstration of elevated ACh levels in PBMCs of MG patients foreshadows potential new avenues for MG research and treatment. [ABSTRACT FROM AUTHOR]

The properties of Cu(Cr) alloy films were measured to evaluate its potential application as self-formed diffusion barrier in copper interconnect. Pure Cu and Cu(4.5 at%Cr) alloy films were deposited on SiO 2 /Si substrates using magnetron sputtering and subsequently annealed in vacuum (2 × 10 −4 Pa) at the temperature of 350 ° C–550 °C. After annealing, the film properties were examined using X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM) and four-point probe (FPP) method. The results indicate that there was no intermetallic compound (copper–silicide) detected at the interface after annealing. A 7 nm Cr rich layer was self-formed at the interface between Cu(Cr) and SiO 2 /Si after annealing which acted as a thermally stable barrier against the diffusion of Cu into SiO 2 . The resistivity of the films decreased with increasing the annealing temperature. After annealing at 550 °C for 1 h, the resistivity of the studied alloy films was 6.9 μΩ cm, which is comparable to that of Cu films (5.17 μΩ cm). These evidences suggest that Cu(Cr) films with excellent thermal stability and low sheet resistance would become a promising material for future advanced barrierless Cu interconnects. [ABSTRACT FROM AUTHOR]

Construction of difluoromethylthioethers (2) and difluorobis(arylthio)methanes (3) from RSX (X = SR, Cl, SO2Ph) and TMSCF2H in the absence of transition metals has been explored. The reaction is dramatically influenced by the nature of the base and the molar ratio of the reactants. Reactions between RSX and TMSCF2H in the presence of CsF provided 2 in good yields, whereas the reaction of RSX with TMSCF2H in the presence of t-BuOK afforded 3 in good yields. These protocols allow for convenient and efficient access to both difluoromethylthioethers and difluorobis(arylthio)methanes. [ABSTRACT FROM AUTHOR]

A novel lightweight sandwich construction with honeycomb-corrugation hybrid core is fabricated by filling the interstices of aluminum corrugations with trapezoidal aluminum honeycomb blocks. The performance of the hybrid structure under quasi-static out-of-plane uniform compression is investigated, both experimentally and theoretically. When all the interfaces in the hybrid structure are fixed using epoxy glue, the proposed structure is found to have strength and energy absorption capacity significantly greater than the sum of those of empty corrugated sandwich and honeycomb-cored sandwich. It is demonstrated that the interaction effect between honeycomb insertions and corrugated plates stabilizes buckling and changes the crushing deformation mechanisms of both constituents, leading to enhanced strength and energy absorption. Comparison with competing lightweight sandwich constructions having equal mass reveals that the proposed hybrid structure exhibits superiority in both strength and energy absorption in the low-density regime. [ABSTRACT FROM AUTHOR]

Background: Difficult airway may result in significant morbidity and mortality. Proficient airway evaluation, therefore, is one of the key elements in the safe conduct of anesthesia. A three-dimensional (3D) printing model was recently introduced for medical application. 3D printing is a fast, convenient, and relatively affordable technique. We present a case in which a 3D-printed airway model was successfully used for airway evaluation. Case presentation: A 77-year-old man who had previously undergone total laryngectomy was scheduled for resection of a pelvic mass. The condition of his airway, however, complicated the procedure. Routine methods to evaluate his airway were not suitable. Therefore, the patient's computed tomography imaging data were used to generate stereolithography files and then to print out 3D models of his trachea. These 3D models enhanced our understanding of his tracheal morphology. They helped us devise a preanesthesia plan and effectively execute it without complications. Conclusion: 3D printing models allow better understanding of morphological changes in the airway and aid preanesthesia planning. The successful outcome of our case suggests 3D printing is a potent tool for evaluating difficult and more widespread use is encouraged. [ABSTRACT FROM AUTHOR]

Honeycomb as sandwich core construction has been established as one of the best candidates among ultralight cellular materials for load-bearing and energy absorption applications. In this paper, by introducing non-uniform mass distribution (gradient) in the core, substantially improved structural performance of a fully-clamped sandwich plate with square honeycomb core is achieved for out-of-plane uniform pressure loading. In-plane gradient of core is defined and achieved via two approaches: web thickness variation and cell size variation. Response of sandwich plates with linear in-plane core gradient is systematically investigated with finite element (FE) simulations. For both quasi-static and blast loading cases, it is found that positively graded cores exhibit advantage in stiffness, strength as well as plastic energy dissipation compared to cores without gradient or with negative gradient. Examination of plastic energy dissipation in a graded core reveals that ribs placed next to its symmetry plane are more sensitive to changes in thickness or location compared to those placed adjacent to the clamped edges. With the total mass of the core constrained, the constituent material can be more efficiently utilized by either increasing the thickness of ribs close to symmetry planes or moving ribs towards the symmetry planes. [ABSTRACT FROM AUTHOR]

To improve the poor transverse shear resistance of corrugated sandwich cores, the present study uses a combined analytical and numerical approach to exploit the idea of filling core interstices with polymer foam. For foam-filled corrugated cores under transverse shear, four collapse modes are considered: elastic buckling, plastic buckling or yielding/fracture of corrugated strut, interfacial debonding/sealing off between corrugation platform and face sheets, and foam shear failure. Analytical models are constructed to determine the transverse shear stiffness and strength. To estimate the elastic/plastic buckling strength of a corrugated strut, the foam insertions are treated as a superposition of Winkler type elastic foundations to support the strut against buckling. Finite element simulations are carried out to validate the model predictions, with good agreement achieved. The sensitivity of transverse shear strength and failure mode to corrugation angle, strut slenderness and strain hardening of strut parent material is systematically studied; collapse mechanism map is constructed, and minimum weight design is carried out. Whether the sandwich is made of metal or fiber-reinforced composite, it is demonstrated that the foam-filled corrugated core exhibits radically enhanced transverse shear response, outperforming competing core topologies such as hollow pyramidal lattices and square honeycombs on the basis of equal mass. [ABSTRACT FROM AUTHOR]

Variation in the expression of genes arises from a variety of sources. It is important to remove sources of variation between arrays of non-biological origin. Non-biological variation, caused by lurking confounding factors, usually attracts little attention, although it may substantially influence the expression profile of genes. In this study, we proposed a method which is able to identify the potential confounding factors and highlight the non-biological variations. We also developed methods and statistical tests to study the confounding factors and their influence on the homogeneity of microarray data, gene selection, and disease classification. We explored an ovarian cancer gene expression profile and showed that data batches and arraying conditions are two confounding factors. Their influence on the homogeneity of data, gene selection, and disease classification are statistically analyzed. Experiments showed that after normalization, their influences were removed. Comparative studies further showed that the data became more homogeneous and the classification quality was improved. This research demonstrated that identifying and reducing the impact of confounding factors is paramount in making sense of gene-disease association analysis. [ABSTRACT FROM AUTHOR]

Although tensor product real-valued wavelets have been successfully applied to many high-dimensional problems, they can capture well only edge singularities along the coordinate axis directions. As an alternative and improvement of tensor product real-valued wavelets and dual tree complex wavelet transform, recently tensor product complex tight framelets with increasing directionality have been introduced in [B. Han, Math. Model. Nat. Phenom., 8 (2013), pp. 18-47] and applied to image denoising in [B. Han and Z. Zhao, SIAM J. Imaging Sci., 7 (2014), pp. 997-1034]. Despite several desirable properties, those directional tensor product complex tight framelets are bandlimited and do not have compact support in the space/time domain. Since compactly supported wavelets and framelets are of great interest and importance in both theory and application, it remains as an unsolved problem whether there exist compactly supported tensor product complex tight framelets with directionality. In this paper, we shall answer this question by proving a theoretical result on directionality of tight framelets and by introducing an algorithm to construct compactly supported complex tight framelets with directionality. Our examples show that compactly supported complex tight framelets with directionality can be easily derived from any given eligible low-pass filters and refinable functions. Several examples of compactly supported tensor product complex tight framelets with directionality have been presented. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the effects of tetrandrine (Tet) on the brain cells of phenobarbital-dependant and -withdrawn rats, and to explore the underlying mechanisms. A total of 100 rats were randomly divided into five groups: The control group, the phenobarbital-dependent model group, and Tet-treated groups of low-, mid- and high-dosages. Following drug withdrawl, the morphological changes of the frontal lobe cells were examined by hematoxylin and eosin (H&E) staining. Immunohistochemical staining was applied to detect the expression of apoptosis-related proteins Bcl-2 and Bax. Reverse transcription-polymerase chain reaction (RT-PCR) and western blotting methods were applied to detect the mRNA and protein expression levels of Bcl-2 and Bax, respectively, in the frontal lobe. The results indicated that Tet effectively reduced the withdrawal symptoms, particularly the weight loss, in phenobarbital-dependent and -withdrawn rats. H&E staining revealed that Tet significantly restored the histopathological changes in the addicted rats in a dose-dependent manner. The immunohistochemical, RT-PCR, and western blot analyses indicated that Tet treatment significantly increased the Bcl-2+ brain cells and the mRNA and protein expression levels of Bcl-2, and decreased the Bax+ cells and the mRNA and protein expression levels of Bax, as well as elevated the ratio of Bcl-2/Bax, in phenobarbital-dependent and -withdrawn rats. Tet may inhibit apoptosis in these addicted rats, in a dose-dependent manner. Tet alleviates the phenobarbital withdrawal symptoms and protects the brain cells against apoptosis, which may be a result of the regulation of the mRNA and protein expression levels of Bcl-2 and Bax. [ABSTRACT FROM AUTHOR]

Dual wavelet frames and their associated dual framelet filter banks are often constructed using the oblique extension principle. In comparison with the construction of tight wavelet frames and tight framelet filter banks, it is indeed quite easy to obtain some particular examples of dual framelet filter banks with or without symmetry from any given pair of low-pass filters. However, such constructed dual framelet filter banks are often too particular to have some desirable properties such as balanced filter supports between primal and dual filters. From the point of view of both theory and application, it is important and interesting to have an algorithm which is capable of finding all possible dual framelet filter banks with symmetry and with the shortest possible filter supports from any given pair of low-pass filters with symmetry. However, to our best knowledge, this issue has not been resolved yet in the literature and one often has to solve systems of nonlinear equations to obtain nontrivial dual framelet filter banks. Given the fact that the construction of dual framelet filter banks is widely believed to be very flexible, the lack of a systematic algorithm for constructing all dual framelet filter banks in the literature is a little bit surprising to us. In this paper, by solving only small systems of linear equations, we shall completely settle this problem by introducing a step-by-step efficient algorithm to construct all possible dual framelet filter banks with or without symmetry and with the shortest possible filter supports. As a byproduct, our algorithm leads to a simple algorithm for constructing all symmetric tight framelet filter banks with two high-pass filters from a given low-pass filter with symmetry. Examples will be provided to illustrate our algorithm. To explain and to understand better our algorithm and dual framelet filter banks, we shall also discuss some properties of our algorithms and dual framelet filter banks in this paper. [ABSTRACT FROM AUTHOR]

The key C-C bond forming step of the Rh-catalysed carboxylation of organoboron compounds with CO2 was investigated by density functional theory (DFT) at the IEFPCM/PBE0/DGDZVP level of theory. With a bidentate phosphane (dppp) ligand, the reaction begins with a transformation from square-planar O-(η1)- bonded to distorted-tetrahedral, η2-bonded CO2 followed by migratory insertion (barrier 12.7 kcal mol-1). The calculations showed that incorporation of electron-donating substituents within either the aryl substrate or the phosphane leads to a slight decrease of the reaction barrier, in excellent agreement with the experimental trends. With a diene ligand (cod), the migratory insertion proceeds directly from the O-(η1)- bonded CO2 (barrier 17.1 kcal mol-1) as a consequence of the diminished σ-donor ability of the diene ligand. Therefore, the diene ligand is predicted to be an inferior choice compared to the diphosphane. Testing of [(cod)Rh(OH)] 2 upon completion of the computations showed no conversion. [ABSTRACT FROM AUTHOR]

Background Royal jelly (RJ) is a proteinaceous secretion produced from the hypopharyngeal and mandibular glands of nurse bees. It plays vital roles in honeybee biology and in the improvement of human health. However, some proteins remain unknown in RJ, and mapping N-glycosylation modification sites on RJ proteins demands further investigation. We used two different liquid chromatography-tandem mass spectrometry techniques, complementary N-glycopeptide enrichment strategies, and bioinformatic approaches to gain a better understanding of novel and glycosylated proteins in RJ. Results A total of 25 N-glycosylated proteins, carrying 53 N-glycosylation sites, were identified in RJ proteins, of which 42 N-linked glycosylation sites were mapped as novel on RJ proteins. Most of the glycosylated proteins were related to metabolic activities and health improvement. The 13 newly identified proteins were also mainly associated with metabolic processes and health improvement activities. Conclusion Our in-depth, large-scale mapping of novel glycosylation sites represents a crucial step toward systematically revealing the functionality of N-glycosylated RJ proteins, and is potentially useful for producing a protein with desirable pharmacokinetic and biological activity using a genetic engineering approach. The newly-identified proteins significantly extend the proteome coverage of RJ. These findings contribute vital and new knowledge to our understanding of the innate biochemical nature of RJ at both the proteome and glycoproteome levels. [ABSTRACT FROM AUTHOR]

Zuojin Wan (ZJW) and Lizhong Wan (LZW) have been widely used in the treatment of Stomach heat and cold syndrome (SH and SC), respectively. In this study, a proton nuclear magnetic resonance (1H NMR) based metabonomic approach was developed to profile SH and SC-related metabolic perturbations in rat serum and to investigate the intervention effects of ZJW and LZW on the corresponding SH and SC. Compared to the conventional macroscopic and histopathological examinations, the metabonomic approach could enable discrimination between SH and SC based on serum metabolic profiles. Meanwhile, 17 and 15 potential biomarkers associated with SH and SC, respectively, which were mainly involved in gastric dysfunction and mucosal lesions, gut microbiotal activity, transmethylation, glucose and lipid metabolism, and amino acid metabolism, were identified. Furthermore, taking the potential biomarkers as drug targets, it was revealed that administration of ZJW and LZW could exclusively reverse the pathological process of SH and SC, respectively, through partially regulating the disturbed metabolic pathways. This work showed biological basis related to SH and SC at metabolic level and offered a new paradigm for better understanding and explanation of "Fang Zheng Dui Ying" principle in traditional Chinese medicine from a systemic view. [ABSTRACT FROM AUTHOR]

During the switching of disconnectors in gas-insulated switchgear (GIS), repeated strikes occur in the contact gap and lead to very fast transient overvoltage (VFTO). Severe VFTO may bring damage to transformers and other equipment. The switching speed of the disconnector is one of the important factors which influences VFTO. There are still different opinions on this factor. Very little quantitative study was done before this paper. In this paper, the whole repeated strike process associated with the switching operation of the disconnector was simulated and analyzed. The polarity and the probability characteristics of breakdown voltage were analyzed. The impacts of the switching speed of the disconnector on VFTO were studied by statistical methods. Comparisons were made between simulated and measured results. The simulation result shows that within a certain range of speed, disconnectors with a lower switching speed generate lower trapped charge voltage after opening operation and lower VFTO magnitude during the opening and closing operations. [ABSTRACT FROM AUTHOR]

Objective: Overexpression of the sonic hedgehog (SHH) signaling pathway is an essential characteristic of pancreatic cancer stem cells (PCSCs) and arsenic trioxide (ATO) is described as a SHH inhibitor. This study evaluates whether ATO has the potential to inhibit viability of PCSCs via binding to SHH-Gli proteins. Methods: Cell counting kit-8 and flow cytometry were used for analyzing apoptosis in cells in vitro. The animal model was an athymic nude mouse model bearing subcutaneous xenografts of SW1990 pancreatic cancer cells. The terminal deoxynucleotidyl transferase dUTP nick end labeling assay and immunohistochemistry were used for tumor tissue analysis. The interaction between Gli1 and ATO was examined by a confocal system and an ultraviolet absorption spectrum assay. Results: ATO induced apoptosis in pancreatic cancer cells, especially CD24+CD44+ cells in vitro. Combination treatment of ATO and low dose gemcitabine inhibited tumor growth by 60.9% (P = 0.004), and decreased the expression of CD24, CD44, and aldehyde dehydrogenase 1 family, member A1 significantly in vivo. ATO changed the structure of the recombinant Gli1 zinc finger peptides in a cell-free condition and the binding action of ATO to recombinant Gli1 was observed in cultured pancreatic cancer cells. Conclusion: ATO may have the potential to inhibit viability of PCSCs via binding to SHH-Gli proteins in vitro and in vivo. [ABSTRACT FROM AUTHOR]

Abstract: A scaleless wing mutant of silkworm, Bombyx mori, has much fewer scales than wild type (WT). The scaleless phenotype was associated with tracheal system developmental deficiency and excessive apoptosis of scale cells. In this study, the wing discs proteins of WT and scaleless during pupation were studied using 2-DE and mass spectrometry. Of the 99 identified protein spots, four critical differentially expressed proteins between WT and scaleless were further verified using Q-PCR. At the first day of pupation (P0) in WT, imaginal disk growth factor (IDGF) was upregulated, whereas actin-depolymerizing factor 1 (ADF1) and profilin (PFN), which associated with cellular motility and cytoplasmic extension, were downregulated. We speculated their coaction counteracts the correct organization of the tracheal system in wing disc. Thiol peroxiredoxin (TPx) was upregulated in scaleless at P0, but its mRNA higher expression occurred in the day before pupation (S4). TPx could inhibit the formation of hydrogen peroxide, preventing the release of cytochrome C and activation of the caspase family protease. Its higher expression in scaleless was responsible for the apoptosis of scale cells delayed. The results provide further evidence that the scaleless phenotype was related to the tracheal system developmental deficiency and excessive apoptosis of scale cells. [Copyright &y& Elsevier]

As a finite dimensional linear space over the rational number field Q, an algebraic number field is of particular importance and interest in mathematics and engineering. Algorithms using algebraic number fields can be efficiently implemented involving only integer arithmetics. We observe that all known finitely supported orthogonal wavelet low-pass filters in the literature have coefficients coming from an algebraic number field. Therefore, it is of theoretical and practical interest for us to consider orthogonal wavelet filter banks over algebraic number fields. In this paper, we formulate the matrix extension problem over any general subfield of ℂ (including an algebraic number field as a special case), and we provide step-by-step algorithms to implement our main results. As an application, we obtain a satisfactory algorithm for constructing orthogonal wavelet filter banks over algebraic number fields. Several examples are provided to illustrate the algorithms proposed in this paper. [ABSTRACT FROM AUTHOR]

In this paper, we first introduce the concept of an adaptive multiresolution analysis (AMRA) structure, which is a variant of the classical MRA structure well suited to the main goal of a fast flexible decomposition strategy adapted to the data at each decomposition level. We then study this novel methodology for the general case of affine-like systems and derive a unitary extension principle (UEP) for filter design. Finally, we apply our results to the directional representation system of shearlets. This leads to a comprehensive theory for fast decomposition algorithms associated with shearlet systems which encompasses tight shearlet frames with spatially compactly supported generators within such an AMRA structure. Also, shearlet-like systems associated with parabolic scaling and unimodular shear matrices are studied within this framework. [ABSTRACT FROM AUTHOR]

High-energy photons from medical accelerators are used to treat tumors in cancer patients. One consequence is the production of neutrons from photonuclear interactions in the high-Z accelerator components. The release and capture of neutrons produce radioactive nuclei that can irradiate patients and medical personnel. The goal of this study is to develop a method for quantifying the activation of accelerator components using MCNPX. To benchmark this method, we took activation measurements from the irradiation of a series of zinc plates using a 55-MeVelectron beam and compared them with MCNPX calculations. The measured cumulative photon-induced activity from 68Zn( γ,p)67 Cu interactions in all of the plates was 10.8 MBq, which is in 5.4% agreement with the calculated value of 10.2 ± 1.1 MBq. Based on these results, a series of simulations were performed in order to optimize the photon- and neutron-induced activity in tungsten for subsequent experiments. The radioactivity from activated short-lived isotopes and subsequent buildup can be significant from repeated accelerator operations during a day. The approach described in this paper is useful in quantifying the origin and the amount of nuclear activation and the buildup of radioactivity. [ABSTRACT FROM AUTHOR]

During radiation therapy treatments, neutron contamination can be a source of unwanted radiation dose to the patient and medical personnel. Accurate cross-section data is needed to characterize the neutron contamination in medical accelerators using Monte Carlo methods. In this study, a comparison of the photoneutron yields using the default LA150U and the Chinese Nuclear Data Center (CNDC) photonuclear cross sections was performed. Thick tungsten plates, each of 0.125-cm thickness (one-third radiation length), were directly irradiated by an electron beam in MCNPX. In order to match typical radiation therapy energy ranges, the energy distribution of the electron beam was modeled as a Gaussian distribution with a mean energy of 18.3 MeV and a 3% full-width at half-maximum. The photoneutron yield using the LA150U is consistently ~12 to 17% higher than those from the CNDC data for each target thickness. The average photoneutron energy difference between the two cross-section libraries ranged from 3 to 42%. No major differences were seen between relative neutron fluences per solid angle for the two cross-section libraries. The discrepancies between the datasets provided above can be attributed to the oversimplification of using the default LA150U 184w cross section for all other naturally occurring isotopes of tungsten. Therefore, the lack of cross-section data in the LA150U library is a definite concern when using MCNPX to determine secondary neutron production in a medical accelerator room since a majority of contamination neutrons are produced in tungsten components. [ABSTRACT FROM AUTHOR]

In this paper, we shall introduce and study a family of multivariate interpolating refinable function vectors with some prescribed interpolation property. Such interpolating refinable function vectors are of interest in approximation theory, sampling theorems, and wavelet analysis. In this paper, we characterize a multivariate interpolating refinable function vector in terms of its mask and analyze the underlying sum rule structure of its generalized interpolatory matrix mask. We also discuss the symmetry property of multivariate interpolating refinable function vectors. Based on these results, we construct a family of univariate generalized interpolatory matrix masks with increasing orders of sum rules and with symmetry for interpolating refinable function vectors. Such a family includes several known important families of univariate refinable function vectors as special cases. Several examples of bivariate interpolating refinable function vectors with symmetry will also be presented. [ABSTRACT FROM AUTHOR]

Ripe fruits of Amomum villosum Lour. are important traditional Chinese medicines and food spices. Due to similar morphological and anatomical characteristics, fruits from some Alpinia species are used clinically as substitutes or adulterants of Fructus Amomi. In this study, we determined the nrDNA ITS1 (internal transcribed space I) sequences from Amomum villosum and ten Alpinia species, which are adulterants of Fructus Amomi. The ITS1 sequences of these species were l75-l79 bp in length, and the G+C contents were 53.37∼56.74%. Sequence alignment revealed that there were 55 polymorphic nucleotide sites among the tested species. The base substitution were 0.57-9.60% within the ten Aplinia species, but 17.61∼21.59% between Amomum villosum and the Alpinia species. These molecular data indicated that ITS1 sequences can be used to differentiate Fructus Amomi and its substitutes or adulterants from various Alpinia species. [ABSTRACT FROM AUTHOR]

Several different in vivo and in vitro bioassays are used to evaluate melanosome transfer efficacy from melanocytes to keratinocytes. However, these methods are complicated and time consuming. Here, we report on a simple, rapid, direct, and reliable in vitro method for observing the process of melanosome transfer from melanocytes to keratinocytes. First, we selected and tested a melanoma cell line RPMI-7951 that can normally synthesize melanin and transfer from mature melanosomes to keratinocytes in vitro. We cocultured these cells with a human ovarian teratoma transformed epidermal carcinoma cell line, which is also capable of accepting melanosomes transferred from melanocytes, as in normal keratinocytes. The cells were cocultured for 24–72 h and double labeled with FITC-conjugated antibody against the melanosome-associated protein TRP-1, and with Cy5-conjugated antibody against the keratinocyte-specific marker keratin 14. The cells were examined by fluorescence microscope and flow cytometry. Melanosome transfer from melanocytes to keratinocytes increased in a time-dependent manner. To verify the accessibility of this method, the melanosome transfer inhibitor, a serine protease inhibitor, 4-(2-aminoethyl) benzenesulfonyl fluoride hydrochloride, and a melanosome transfer stimulator, α-melanocyte-stimulating hormone, were added. The serine protease inhibitor decreased melanosome transfer, and α-melanocyte-stimulating hormone increased melanosome transfer, in a dose-dependent manner. In conclusion, this is a simple, rapid, and effective model system to quantify the melanosome transfer efficacy from melanocytes to keratinocytes in vitro. [ABSTRACT FROM AUTHOR]

In this paper, we obtain symmetric C∞ real-valued tight wavelet frames in L2(ℝ) with compact support and the spectral frame approximation order. Furthermore, we present a family of symmetric compactly supported C∞ orthonormal complex wavelets in L2(ℝ). A complete analysis of nonstationary tight wavelet frames and orthonormal wavelet bases in L2(ℝ) is given. [ABSTRACT FROM AUTHOR]

The article presents a study on the chronic changes in rat tail vertebral discs caused by percutaneous needle puncture. It aims to produce a simple animal model of disc degeneration. The study revealed that needle punctures with full or half penetration induced important disc space narrowing histologic alterations of degeneration as early as one or two weeks after injury. It concluded that tail disc percutaneous needle puncture is an easy method for inducing disc degeneration.

Refinable functions and cascade algorithms play a fundamental role in wavelet analysis, which is useful in many applications. In this paper we shall study several properties of refinable functions, cascade algorithms, and wavelets, associated with Hölder continuous masks, in the weighted subspaces L2, p, γ (ℝ) of L2(ℝ), where 1 ≤ p ≤ ∞, γ ≥ and f ∈ L2, p, γ (ℝ) means ... In particular, ... and ... For a mask â ∈ Cβ (핋) with β 0 and â(0) = 1 (that is, â is a Hölder continuous mask with Hölder exponent β), we prove that the cascade algorithm associated with the mask â converges in the space L2, ∞, 0 (ℝ) if and only if &nu2(â) > 0, where the quantity &nu2(â) will be defined in this paper and plays an important role in our study of refinable functions and cascade algorithms with Hölder continuous masks. In particular, if the shifts of a refinable function φ, satisfying φ(2⋅) = âφ, are stable in L2(ℝ), then we must have &nu2(â) > 0, and therefore the cascade algorithm associated with mask â converges in the space L2, ∞, 0 (ℝ) Based on this result, we are able to settle several problems on refinable functions, cascade algorithms, and wavelets associated with masks having infinitely many nonzero Fourier coefficients. As an application of the characterization of the convergence of a cascade algorithm in the space L2, ∞, 0(ℝ), we are able to show that for a mask â having exponential decay of order r > 0, the cascade algorithm associated with mask â converges in the weighted space L2, 1, γ(ℝ) for 0 < γ < 2r if and only if ν2(â) > 0. Consequently, if a mask â has exponential decay of order r > 0 and ν2(â) > 0, then its standard refinable function φ, defined by ... must have exponential decay of order 2r in L2(ℝ) that is, ... for all 0 < γ < 2r. As another application of the characterization of the convergence of a cascade algorithm in the space L2, ∞, 0(ℝ), we completely characterize biorthogonal wavelets and Riesz wavelets in L2(ℝ), which are derived from refinable functions and whose involved wavelet filters in the frequency domain are Hölder continuous. We shall also investigate some basic properties of the quantity ν2(â) and discuss how to calculate and estimate ν2(â). Examples using fractional splines and the Butterworth filters will be given to illustrate the results in this paper. [ABSTRACT FROM AUTHOR]

Ni(II) and Pd(II) complexes based on N-((1 H-pyrrol-2-yl)methylene)-2-(diphenylphosphino)benzenamine were synthesized and characterized. X-ray diffraction studies on complexes 1, 2, and 4revealed that N, N, P, and halogen atoms coordinated to metal, with distorted square planar geometries in all cases. Upon treatment with modified methylaluminoxane (MMAO), the [N −NP]Ni(II)X complexes are robust and exhibit high activity for the vinyl addition polymerization of norbornene (up to 5.46 × 10 7g PNB/mol(Ni)·h·atm). [ABSTRACT FROM AUTHOR]

This paper is to construct Riesz wavelets with short support. Riesz wavelets with short support are the objective of interest in both theory and application. In theory, it is known that a B-spline of order m has the shortest support among all compactly supported refinable functions with the same regularity. However, it remained open whether a Riesz wavelet with the shortest support and m vanishing moments can be constructed from the multiresolution analysis generated by the B-spline of order m. In various applications, a Riesz wavelet with a short support, a high order of regularity, and vanishing moments is often desirable in signal and image processing, since they have a good time frequency localization and approximation property, as well as fast algorithms. This paper presents a theory for the construction of Riesz wavelets with short support and gives various examples. In particular, from the multiresolution analysis whose underlying refinable function is the B-spline of order m, we are able to construct the shortest supported Riesz wavelet with m vanishing moments. The support of the wavelet functions can be made even shorter by reducing their orders of vanishing moments. The study here also provides a new insight into the structures of the spline tight frame systems constructed in [A. Ron and Z. Shen, J. Funct. Anal., 148 (1997), pp. 408-447, I. Daubechies, B. Han, A. Ron, and Z. Shen, Appl. Comput. Harmon. Anal., 14 (2003), pp. 1-46, B. Han and Q. Mo, Proc. Amer. Math. Soc., 132 (2004), pp. 77-86] and bi-frame systems in [I. Daubechies, B. Han, A. Ron, and Z. Shen, Appl. Comput. Harmon. Anal., 14 (2003), pp. 1-46, I. Daubechies and B. Han, Constr. Approx., 20 (2004), pp. 325-352]. [ABSTRACT FROM AUTHOR]

An ideal analog-to-digital (A/D) converter prefilters a signal by an ideal lowpass filter. Recent research on A/D conversion based on shift-invariant spaces reveals that prefiltering signals by quasiprojections into shift-invariant spaces provides more flexible choices in designing an A/D conversion system of high accuracy. This paper focuses on the accuracy of such prefiltering, in which the aliasing error efλ is found to behave like ‖efλ‖2 = O(λ-α) with respect to the dilation λ of the underlying shift-invariant space, provided that the input signal f is Lipschitz-α continuous. A formula to calculate the coefficient of the decay rate is also figured out in this paper. [ABSTRACT FROM AUTHOR]

It has been found that the quantization error e for a conventional oversampled analog-to-digital (A/D) conversion behaves like ‖e‖² = O(r²) with respect to the sampling rate r. Recently, conventional A/D conversion has been extended to A/D conversion based on shift-invariant spaces. As consequences of such extension, it offers rich choices to build a nonideal A/D conversion system of high accuracy and low computational complexity, as well as reduces the noise sensitivity and computational complexity in digital-to-analog (D/A) conversion. Therefore, it is necessary to establish the estimate of quantization error for the extended A/D conversion based on shift-invariant spaces. In this paper, we introduce a constructive method to establish an estimate of the quantization error as &verbar;e&verbar;² = O(r²) for oversampled A/D conversion in shift-invariant spaces. Meanwhile, we demonstrate that the bit rate required to encode the converted digital signal in such A/D conversion scheme only increases as the logarithm of the sampling ratio. Therefore, the quantization error is an exponentially decaying function of the bit rate. In order to establish such an estimate, we need the nonuniform sampling theorem for shift-invariant spaces, which, as the necessary preparation, is studied prior to introducing the constructive method. [ABSTRACT FROM AUTHOR]

This work studied the relationship of any two nucleotides in genomic sequences, coding sequences and full-length cDNAs. We made a statistical hypothesis that there exist no interactions between any two nucleotides in sequences, therefore, a hypothetical combination distribution of two nucleotides is considered and the difference between the hypothetical combination distribution and the actual distribution is used to measure the average interaction between the two nucleotides. As a result, we found that the interactions between any two nucleotides are clearly and closely related with dampable wavelike patterns along the sequences. Based on the results we daringly make some hypotheses on several biological topics. Further, studies on the wave may provide new clues for gene prediction and genome structure study. [ABSTRACT FROM AUTHOR]

We consider the perturbed Schrödinger equation, which is an elliptic operator with unbounded coefficients. We use wavelets adapted to the Schrödinger operator to deal with problems on the unbounded domain. The wavelets are constructed from Hermite functions, which characterizes the space generated by the Schrödinger operator. We show that the Galerkin matrix can be pre-conditioned by a diagonal matrix so that its condition number is uniformly bounded. Moreover, we introduce a periodic pseudo-differential operator and show that its discrete Galerkin matrix under periodic wavelet system is equal to the Galerkin matrix for the equation with unbounded coefficients under the Hermite system. The convergence is proved in the L[sup 2] topology. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Design for Environment (DfE) optimizes the relationship and interaction of the economic system and the environmental system, and strives to produce a sustainable development and enterprise integration. The driving force behind DfE includes customers, international agencies, and governmental agencies, who are all stake holders in the environmental well being. The methodologies and tools of DfE generally fall under three loose categories, namely, decision making, design support, and material flow. In DfE there are a number of enablers for decision making, examples of which include end-of-life strategies and Life Cycle Assessment (LCA). With the development of DfE, sophisticated design support methodologies and tools are necessary for the early stage of design regarding the environmental impact, working as guidance to the design engineers. The three main design support constituents, discussed in this paper, include LCA, design for Disassembly, and Expert Systems. Environmental impact resulting from modern industry has spurred interest in the material and energy flow of industry systems. These flows are viewed not only to be fundamental to environmental problems, but also as agents of financial success. The scope of DfE has three elements, namely, strategy, guidelines and procedures, and application. It is noted that the next frontier of DfE is the incorporation of society models that include technology, government, customers, recyclers, and their respective interaction. This paper presents recent developments and current activities of DfE, specifically the areas of decision-making, design support, material flow analysis and application. Additionally, a brief discussion of future trends is presented and observations are made on how to further realize DfE in industry and in the entire society while protecting the environment. [ABSTRACT FROM AUTHOR]