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Summary Denitrification occurs actively in rice field soils. In the present study, the responses of nirK and nirS denitrifier communities to nitrate addition in the anoxic rice soil were determined through molecular analyses of nitrite reductase genes nirK and nirS and 16S rRNA genes. Denitrification occurred rapidly when nitrate was added at the beginning of anoxic incubation (experiment I). The structure of nirK-type denitrifiers did not change; but their abundance as determined by quantitative (real-time) PCR increased in nitrate treatments compared with control. Both the structure and abundance of nirS denitrifiers remained unaffected in experiment I. The rate of denitrification was slowed down when nitrate was added 20 days after the onset of anoxic incubation (experiment II). The structure and abundance of nirK-type denitrifier community did not respond to nitrate addition; but the nirS community changed substantially in this experiment. The copy number of nirS genes increased by an order of magnitude in the treatments of 5 mM and 10 mM nitrate compared with control. The terminal restriction fragment length polymorphism (T-RFLP) analysis of nirS genes revealed that the 100 bp T-RF substantially increased in the nitrate treatments. Cloning and sequence analysis indicated that this T-RF had similarity of up to 90% with Herbaspirillum sp. T-RFLP profiles of the bacterial 16S rRNA genes also showed that Herbaspirillum sp. increased after nitrate amendments. Collectively, the nirK-type denitrifiers were probably active at the beginning of anaerobic incubation, while the nirS denitrifiers, especially those related with Herbaspirillum sp. probably were more active when anaerobic condition was fully developed. [ABSTRACT FROM AUTHOR]

Abstract: The problem of finding the least change adjustment to a stiffness matrix modeled by finite element method is considered in this paper. Desired stiffness matrix properties such as symmetry, sparsity, positive semidefiniteness, and satisfaction of the characteristic equation are imposed as side constraints of the constructed optimal matrix approximation for updating the stiffness matrix, which matches measured data better. The dual problems of the original constrained minimization are presented and solved by subgradient algorithms with different line search strategies. Some numerical results are included to illustrate the performance and application of the proposed methods. [Copyright &y& Elsevier]

How to build and maintain a reliable yet flexible circuit is a fundamental question in neurobiology. The nervous system has the capacity for undergoing modifications to adapt to the changing environment while maintaining its stability through compensatory mechanisms, such as synaptic homeostasis. Here, we describe our findings in the Drosophila larval visual system, where the variation of sensory inputs induced substantial structural plasticity in dendritic arbors of the postsynaptic neuron and concomitant changes to its physiological output. Furthermore, our genetic analyses have identified the cyclic adenosine monophosphate (cAMP) pathway and a previously uncharacterized cell surface molecule as critical components in regulating experience-dependent modification of the postsynaptic dendrite morphology in Drosophila. [ABSTRACT FROM AUTHOR]

The Integrated Biosphere Simulator (IBIS)-a Dynamic Global Vegetation Model-was validated by simulating the potential natural vegetation map of China using data on monthly mean climate from 1961 to 1990, soil texture, and topography. Although the vegetation map simulated by IBIS was able to describe the sketch of vegetation patterns in China, the distributions of several plant functional types (PFTs) and vegetation types were still simulated incorrectly, especially in eastern temperate areas, southern subtropics, the southern Sichuan basin, and the Hengduan mountains area. By adjusting some of the climatic constraints and physiological parameters of PFTs defined in IBIS, the simulated distributions of PFTs became reasonable, and the simulated vegetation map fitted the natural vegetation map better. The kappa statistic between the simulated and the natural vegetation maps was 0.76, an increase of 16.9% from the previous parameter adjustment of 0.65. Correspondingly, the degree of agreement between these two maps rose from 'good' to 'very good'. After the parameter adjustments, IBIS became more suitable for the large-scale simulation of Chinese natural vegetation distributions and could provide a powerful support to reveal the dynamic responses of terrestrial ecosystems to climate change in China. [ABSTRACT FROM AUTHOR]

n electrostatically driven tunable radio frequency (RF) inductor with large inductance tuning range consisting of electroplated soft magnetic permalloy (NiFe alloy) plate was proposed in this paper. The fabricated tunable inductor exhibits a large tunable inductance range up to 77.8%, together with improved quality factor (Q-factor) at high frequencies. Such tunability of inductance and Q-factor was due to the magnetoelectric coupling effect between the soft magnetic permalloy plate and the spiral inductor, which lead to the magnetic flux of the inductor and mutual inductance change. The concept of tuning inductance by using electroplated soft magnetic permalloy has large potential for wide range RFIC applications. [ABSTRACT FROM AUTHOR]

The aims of this study were to investigate the cognitive function of Chinese amyotrophic lateral sclerosis (ALS) patients. Twenty-two patients with ALS were enrolled and a group of 60 healthy individuals were enrolled as a control group. The Extended Scale for Dementia (ESD) was used to evaluate cognitive function and the Hamilton Depression Scale was used for the assessment of depression. In addition, the Modified Norris Scale was used to assess medulla oblongata and limb function. The overall ESD scores were significantly lower in the ALS patients; however, no correlation was found between individual scores of cognitive function and the overall Modified Norris Scale scores. A majority of ALS patients had significantly reduced cognitive function, suggesting the pathological involvement of areas in the brain outside the motor area. This study shows that through the assessment of cognitive function, abnormalities in cognitive function in ALS patients can be identified. [ABSTRACT FROM AUTHOR]

Summary: We designed an epidermal growth factor (EGF)-containing polyamidoamine (PAMAM) Generation 4 dendrimer vector labeled with quantum dots for targeted imaging and nucleic acid delivery. 1H NMR, SDS–PAGE, and Western blotting were applied to characterize the synthesized G4.0-GGG-EGF nanoparticles. Targeting efficiency, cell viability, proliferation, and intracellular signal transduction were evaluated using HN12, NIH3T3, and NIH3T3/EGFR cells. We found that EGF-conjugated dendrimers did not stimulate growth of EGFR-expressing cells at the selected concentration. Consistent with this, minimal stimulation of post-receptor signaling pathways was observed. These nanoparticles can localize within cells that express the EGFR in a receptor-dependent manner, whereas uptake into cells lacking the receptor was low. A well characterized vimentin shRNA (shVIM) and yellow fluorescent protein (YFP) siRNA were used to test the delivery and transfection efficiency of the constructed targeted vector. Significant knockdown of expression was observed, indicating that this vector is useful for introduction of nucleic acids or drugs into cells by a receptor-targeted mechanism. [ABSTRACT FROM AUTHOR]

Abstract: A novel immunoassay that detects simultaneously hepatitis B virus (HBV) PreS1 and/or core-related antigens was developed and evaluated for its potential for detecting hepatitis B surface antigen (HBsAg) variants. The detection limits of the assay was 102.9±0.5 copies/mL (mean±SD) for HBsAg-positive sera with different genotypes, and 103.5±1.2 copies/mL for HBsAg variants sera. The specificity of the assay was 99.9% (95% CI: 99.7–99.9%, 4551 healthy individuals). The sensitivities were 93.9% (95% CI: 92.8–94.9%), 59.3% (95% CI: 38.7–77.6%) and 80% (95% CI: 44.4–97.5%) in three independent groups which include: 2065 hepatitis patients, 27 patients with occult hepatitis B and 10 HBsAg variants, respectively. In addition, a novel premature stop code mutation at position 112 of HBsAg was observed in two patients with chronic hepatitis B with different genotypes. [Copyright &y& Elsevier]

In this work, we describe a novel polyamidoamine (PAMAM) dendrimer hydrogel (DH) platform with potential for tissue engineering and drug delivery. With PAMAM dendrimer G3.0 being the underlying carrier, polyethylene glycol (PEG) chains of various lengths (MW = 1500, 6000, or 12000 g mol−1) were coupled to the dendrimer to different extents, and the resulting PEGylated PAMAM dendrimers were further coupled with acrylate groups to yield photoreactive dendrimer macromonomers for gel formation. It was found that gelation based on photoreactive PAMAM G3.0 macromonomers was restricted by the degree of PEGylation, PEG chain length, and the distribution of acrylate groups on the dendrimer surface. Further, the architecture of the photoreactive macromonomers affects the structural stability and swelling of the resultant networks. A completely cross-linked network (DH-G3.0-12000H) with a high water swelling ratio was created by UV-curing of PAMAM dendrimer G3.0 coupled with 28 PEG 12000 chains in the presence of the eosin Y-based photoinitiating system. The disintegration of DH-G3.0-12000H was pH-insensitive. DH-G3.0-12000H was found to have similar cytocompatibility to un-cross-linked G3.0-12000H but a significantly lower cellular uptake by macrophages. With PAMAM dendrimer G3.5 being the underlying carrier, the dendrimer modified with 43 PEG 1500 chains was able to form a completely cross-linked network (DH-G3.5-1500H) by UV-curing in the presence of the eosin Y-based photoinitiating system. DH-G3.5-1500H exhibited pH-dependent disintegration. Its disintegration ratio increased with pH. PAMAM dendrimer hydrogels uniquely express the structural characteristics of both PEG hydrogel and PAMAM dendrimer and have potential for various applications in tissue engineering and drug delivery. [ABSTRACT FROM AUTHOR]

Abstract: This paper introduces a new hybrid genetic algorithm to solve twice continuously differentiable non-linear programming (NLP) problems. The algorithm combines the genetic algorithm with local solver differently from some hybrid genetic algorithms. Numerical experiments show the new hybrid genetic algorithm can obtain results better than the known ones reported by the literatures. [Copyright &y& Elsevier]

Abstract: In this study, the bounds for eigenvalues of the Laplacian operator on an L-shaped domain are determined. By adopting some special functions in Goerisch method for lower bounds and in traditional Rayleigh–Ritz method for upper bounds, very accurate bounds to eigenvalues for the problem are obtained. Numerical results show that these functions can also be successfully used to solve the problem on the region with other reentrant angle. [Copyright &y& Elsevier]

In addition to the well characterized processive replication reaction catalyzed by the DNA polymerase III holoenzyme on single-stranded DNA templates, the enzyme possesses an intrinsic strand displacement activity on flapped templates. The strand displacement activity is distinguished from the single- stranded DNA-templated reaction by a high dependence upon single-stranded DNA binding protein and an inability of γ-complex to support the reaction in the absence of τ. However, if γ-complex is present to load β2, a truncated r protein containing only domains Ill-V will suffice, This truncated protein is sufficient to bind both the a subunit of DNA polymerase (Pol) III and χψ. This is reminiscent of the minimal requirements for Pol III to replicate short single-stranded DNA-binding protein (SSB)-coated templates where τ is only required to serve as a scaffold to hold Pol III and χ in the same complex (Glover, B., and McHenry, C. (1998)1. Biol. Chem, 273, 23476 -23484). We propose a model in which strand displacement by DNA poly- merase III holoenzyme depends upon a Pol III-τ-ψ-χ-SSB binding network, where SSB is bound to the displaced strand, stabilizing the Pol Ill-template interaction. The same interaction network is probably important for stabilizing the leading strand polymerase interactions with authentic replication forks. The specificity constant (kcat/Km) for the strand displacement reaction is ∼300-fold less favorable than reactions on single-stranded templates and proceeds with a slower rate (150 nucleotides/s) and only moderate processivity (∼300 nucleotides). PriA, the initiator of replication restart on collapsed or misasasembled replication forks, blocks the strand displacement reaction, even if added to an ongoing reaction. [ABSTRACT FROM AUTHOR]

Summary Addition of nitrate strongly inhibits CH4 production from anoxic soil. The main mechanisms were considered to be the substrate competition and the toxic effect of denitrification intermediates on the methanogenesis. However, it is unclear whether these inhibitory effects are reflected in the structure and dynamics of methanogenic community in the soil. In the present study, the response of methanogenic archaeal community to nitrate addition was determined using terminal restriction fragment length polymorphisms in combination with cloning and sequencing of archaeal 16S rRNA genes. When nitrate was added at the beginning of an anoxic incubation of rice field soil, denitrification occurred rapidly and the denitrification intermediates were detected only for a short time. Total production of CH4 was reduced, but no obvious effect on the structure of methanogenic community was observed. In contrast, when nitrate was added 20 days after the anoxic incubation, the denitrification intermediates obviously accumulated. CH4 production was completely suppressed for 7 and 16 days from treatments of 5 and 10 mM nitrate respectively. The dynamics of methanogenic community also diverged greatly from the control. While the hydrogenotrophic methanogens increased and the acetoclastic methanogens decreased with the incubation in the control soil, the structure and abundance of the methanogenic community remained unchanged after the addition of nitrate. Methanogenesis resumed when the denitrification intermediates were depleted in soil. The analysis of carbon isotopic signals revealed that hydrogenotrophic methanogenesis recovered faster than acetoclastic methanogenesis. Our study suggests that the accumulation of denitrification intermediates has a strong inhibitory effect on the activity but not the structure of methanogenic community. [ABSTRACT FROM AUTHOR]

BACKGROUND: Drug resistance profiles of human immunodeficiency virus-1 (HIV-1) in treatment-naïve infections have been reported in developed countries. However, little is known in developing countries, including China, especially in treatment-naïve volunteer blood donors. STUDY DESIGN AND METHODS: Fifty-two HIV-1–positive samples of blood donors were collected from 2005 to 2006 in Yunnan, China. Recent and long-term infections were distinguished by the HIV-1 subtypes B, E, and D immunoglobulin G-capture enzyme immunoassay assay. The nucleotide sequences of pol genes were amplified and sequenced. Phylogenetic tree and drug resistance analyses were performed. RESULTS: Of 49 samples successfully analyzed, circulating strains were circulating recombinant form (CRF)08_BC (51.0%), CRF07_BC (24.5%), CRF01_AE (20.4%), and B (4.1%). No protease inhibitors (PI) major drug resistance mutation (DRM) was detected. Six samples (12.2%) displayed seven minor PI DRMs. Nine samples (18.4%) displayed 10 nucleoside reverse transcriptase inhibitor DRMs, and DRMs to nonnucleoside reverse transcriptase inhibitors were present in one sample (2.0%). There was only one sample of the 49 (2.0%) in which the DRMs were of sufficient magnitude to result in a clinical change to drug susceptibility, but even in this sample, the clinical effect of these DRMs was predicted to be low. Significant differences were not observed between the long-term and recent infected population. Differences in DRMs were not observed between peripheral blood mononuclear cells and plasma within an individual. CONCLUSIONS: CRF_BC was the dominant subtype circulating in HIV-1–infected donors in Yunnan. Prevalence of genotypic drug resistances among donors in Yunnan was low in this study. Surveillance on HIV-1 infections among blood donors should be continued in China. [ABSTRACT FROM AUTHOR]

Abstract: We report a facile synthesis of highly ordered mesoporous titania–zirconia composites with broad Ti/Zr ratios via an evaporation-induced self assembly (EISA) process. Amphiphilic poly(alkylene oxide) block copolymers, P123 and F127, serve as structure-directing agents (SDAs). By adjusting initial molar ratios of copolymer to metal precursors, titania–zirconia nanocomposites with controlled texture and composition are obtained in a wide range from 10 to 90mol% TiO2. Small-angle X-ray diffraction (SAXRD) and transmission electron microscopy (TEM) measurements reveal the two-dimensional (2D) hexagonal mesostructure (p6mm) with large-domain regularity. These mesostructured composites possess large surface areas and pore volumes, narrow pore size distributions, and abundant surface Lewis acid sites, resulting in unique photocatalytic activities for degradation of rhodamine-B and hydrogen evolution in methanol aqueous solution. Their good photocatalytic abilities are ascribed to the cooperative effect of the porosity and crystallinity. [Copyright &y& Elsevier]

Abstract: The nanoscience and nanotechniques have brought with new chance for new applications of some traditional materials, for instance, ceria-based materials, which are of great interest due to their wide applications, in particular, as redox or oxygen storage promoters in the three-way catalysts, catalysts for H2 production from fuels, and solid state conductors for fuel cells. We highlight here current research activities focused on the controlled synthesis and assembly of ceria-based nanomaterials. We begin with a brief introduction to the urgency for research of ceria-based nanomaterials and our different consideration. Typical synthesis is then discussed with examples of nanosized ceria, ceria–zirconia solid solutions, and doped ceria developed by our group and the others. Controlled synthesis to manipulate the shape, crystal plane, and size is the topic of this article, with approaches elaborated for the assembly of ceria-based materials. Finally, we conclude this article with personal understandings and perspectives on this exciting realm. [Copyright &y& Elsevier]

Abstract: The nanocrystalline TiC powders were synthesized by mechanical alloying (MA) from the mixture of pure titanium and graphite in vacuum, argon and hydrogen milling atmospheres, respectively. The phase transformation and powder morphology characteristics were studied by using XRD and TEM. The results showed that synthesizing mechanism and reaction velocity changed when Ti and C mixture were milled in different atmospheres. It was found that nanocrystalline TiC powders were fabricated by mechanical alloying for 1h at a ball-to-powder weight ratio of 40:1 and rotational speed of 450rpm in planetary ball-mill in argon atmosphere and vacuum. The formation mechanism was mechanically induced self-propagating reactive synthesis (MSR). However, the formation of intermediate phase TiH2 changed the mole ratio of Ti and C, brittle phase proportion and energy aggregation in the powder, consequently resulted in reaction controlled by gradual diffusion when the milling atmosphere was hydrogen gas. So the synthesis time extended to 6h under hydrogen atmosphere on the same milling process. [Copyright &y& Elsevier]

Abstract: In this paper, chaos in a nuclear spin generator is revisited. To confirm the numerically demonstrated chaotic behavior in the nuclear spin generator, we resort to Poincaré map technique and present a rigorous computer-assisted verification of horseshoe chaos by virtue of topological horseshoes theory. [Copyright &y& Elsevier]

Abstract: The nanocrystalline Ti(C,N) powders were synthesized by mechanical alloying (MA) from the mixture of pure titanium, graphite and titanium nitride. The influence of nickel and molybdenum additions on the reaction was also studied. The phase transformation and powder morphology characteristics were studied further by using XRD and TEM. It was found that nano-sized Ti(C,N) powders were fabricated by mechanical alloying for 20h at a ball-to-powder weight ratio of 30:1 and rotational speed of 400rpm in planetary ball mill. The solid reaction included two stages: at the first stage, carbon atoms diffused into the titanium and formed Ti(C) supersaturated solid solution, then carbon atoms reacted with titanium to synthesize TiC; at the second stage, C and N atoms interdiffused, then Ti(C,N) solid solution was synthesized. Moreover, 10wt.% nickel or molybdenum additions in the mixture could accelerate the synthesis of nanometer Ti(C,N) powders. The accelerating efficiency of Ni was superior to that of Mo. [Copyright &y& Elsevier]

The significant growth in freight traffic and relevant crashes has aroused increasing concerns about road safety threats in local communities. We use data from the Minneapolis-St. Paul Metropolitan Area and examine the spatial relationship between freight-related crashes and neighborhoods with low-income and minority populations. We find that both household income and percentage of minority population are significantly correlated with the density of both freight-related crashes and freight-related crashes causing severe injuries and fatalities. The results indicate that freight-related crashes are subject to a spatial inequity problem. The findings underscore the importance of incorporating freight-related safety improvement within these low-income and minority neighborhoods. • The relationship between freight-related crashes and socioeconomics of neighborhoods is examined. • Lower-income and minority neighborhoods have a higher risk of freightrelated crashes. • A coverage validity of the results is revealed in both the census tract and block group level analyses. • Policy implications on local traffic safety improvements and freight planning are provided based on the findings. [ABSTRACT FROM AUTHOR]

• A dynamic programming approach to evaluate emission permit trading is developed. • Selling and purchasing bounds on production firms with non-negligible fixed transaction setup costs. • The optimal production and permit trading policies are partially characterised. • A well-performed heuristic policy and a tight lower bound are proposed. • The heuristic policy performs better than the traditional methods. New technologies such as artificial intelligence (AI) play important roles in transportation emissions trading platforms. Due to the complexity and stochastically changing prices of emissions, an effective algorithm is needed in these platforms to optimize the use of emissions. By setting an upper bound for buying and a lower bound for selling, such an algorithm can reduce trading risk and ensure the stability of trading platforms. In this study, we developed an automatic emissions permit trading system using a dynamic programming approach with selling and purchasing bounds for transportation firms with non-negligible fixed transaction setup costs. We partially characterize the optimal transportation and permit trading policies by exploiting a new mathematical property that is suitable for a two-dimensional control system. We attempt to elucidate the optimal coordination of permit trading and permit consumption for a transportation firm facing both the Markov price process and random demand during a multi-period planning horizon. We prescribe an optimal trading policy and propose a well-performed heuristic policy and a tight lower bound for the platform. We also show that the easily implemented heuristic policy would not significantly increase emissions. Our findings contribute to the literature and provide guidance to help transportation firms using AI platforms. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, we study a three-dimensional general model of artificial neural network (ANN). To confirm the chaotic behavior in this neural network demonstrated in numerical studies, we consider a cross-section properly chosen for the attractor obtained and study the dynamics of the corresponding Poincaré map, and rigorously verify the existence of horseshoe by computer-assisted verification arguments. [Copyright &y& Elsevier]

It is shown that emergent chaos synchronization can take place in coupled nonchaotic unit dynamical systems. This is demonstrated by coupling two nonchaotic cellular neural networks, in which the couplings give rise to a synchronous chaotic dynamics and in the meanwhile the synchronous dynamics is globally asymptotically stable, thus chaos synchronization takes place under the suitable couplings. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, a new hybrid genetic algorithm is proposed, which combines the genetic algorithm with hill-climbing search steps differently from some former algorithms. The new algorithm can be widely applied to a class of global optimization problems for continuous functions with box constraints. Finally, numerical examples show that this algorithm can yield the global optimum with high efficiency. [Copyright &y& Elsevier]

Abstract: In this paper, a modified method by means of an evolution strategy (ES) is introduced for computing eigenvalue bounds of interval matrices. Then a sufficient condition theorem of the evolutionary strategy is presented which guarantees the convergence in probability of the method. The numerical examples show the method can effectively yield accurate bounds for interval eigenvalues. [Copyright &y& Elsevier]

Abstract: In this paper, the Chebyshev collocation method with an improved step for computing the approximate eigenvalues of regular Sturm–Liouville problems is proposed. The method is investigated for applying to the Sturm–Liouville problems with two points and (semi-)periodic boundary conditions. The new step simplifies the computation by solving a generalized matrix eigenvalue problem instead of solving a high order algebraic equation required by the original method and thus more accurate results can be achieved. The numerical results are encouraging. [Copyright &y& Elsevier]

Abstract: The development of biological processes for fossil energy utilization has received increasing attention in recent years. There are abundance of lignite resources in China and the lignite, a low-grade coal, can be transformed by a Penicillium sp. After fungal transformation, the contents of humic acid and water-soluble humic material increased from 38.6% to 55.1%, and from less than 4.0% to 28.2%, respectively. The differences in chemical properties of crude lignite humic acid (aHA), fungal transformed lignite humic acid (bHA) and water-soluble humic material from fungal transformed lignite (WS) were studied. Elemental analysis and size exclusion chromatography showed that the N content of bHA increased by 47.36% compared with aHA, and the molecular mass of bHA was smaller than aHA. And the WS with the smallest molecular mass contained most content of N. The 13C NMR and FT-IR spectra of aHA and bHA showed that aHA contained more aromatic structure than bHA. [Copyright &y& Elsevier]

Summary: Background: Although sleep is an important process essential for life, its regulation is poorly understood. The recently developed Drosophila model for sleep provides a powerful system to genetically and pharmacologically identify molecules that regulate sleep. Serotonin is an important neurotransmitter known to affect many behaviors, but its role in sleep remains controversial. Results: We generated or obtained flies with genetically altered expression of each of three Drosophila serotonin receptor subtypes (d5-HT1A, d5-HT1B, and d5-HT2) and assayed them for baseline sleep phenotypes. The data indicated a sleep-regulating role for the d5-HT1A receptor. d5-HT1A mutant flies had short and fragmented sleep, which was rescued by expressing the receptor in adult mushroom bodies, a structure associated with learning and memory in Drosophila. Neither the d5-HT2 receptor nor the d5-HT1B receptor, which was previously implicated in circadian regulation, had any effect on baseline sleep, indicating that serotonin affects sleep and circadian rhythms through distinct receptors. Elevating serotonin levels, either pharmacologically or genetically, enhanced sleep in wild-type flies. In addition, serotonin promoted sleep in some short-sleep mutants, suggesting that it can compensate for some sleep deficits. Conclusions: These data show that serotonin promotes baseline sleep in Drosophila. They also link the regulation of sleep behavior by serotonin to a specific receptor in a distinct region of the fly brain. [Copyright &y& Elsevier]

Abstract: The apparent molar volumes of l-alanine, dl-serine, dl-threonine, l-histidine, glycine, and glycylglycine in water and in the aqueous solutions of NaCl and DMSO with various concentrations at T =298.15 K have been measured by the precise vibrating-tube digital densimeter. The calculated partial molar volumes at infinite dilution have been used to obtain corresponding transfer volumes from water to various solutions. The experimental results show that the standard partial molar volumes of the above amino acids and peptide at the dilute DMSO aqueous solutions are very close to those in water. However, the volumes show several types of variations with the increase of the concentrations of DMSO due to different types of side chain of amino acids, which should be discussed specifically. The NaCl changes considerably the infinite dilution standard partial molar volumes of the above amino acids and peptide in the aqueous solutions. The infinite dilution standard partial molar volumes of the each amino acids and peptide increase with the concentrations of NaCl. The experimental results have been rationalized by a cosphere overlap model. [Copyright &y& Elsevier]

C25H23NO3, monoclinic, P21/c (no. 14), a = 10.972(6) Å, b = 7.392(4) Å, c = 25.804(10) Å, β = 109.349(18)°, V = 1974.6(17) Å3, Z = 4, Rgt(F) = 0.0640, wRref(F2) = 0.2381, T = 293(2) K. [ABSTRACT FROM AUTHOR]

Abstract: In this paper a class of simple chaotic Hopfield neural networks is presented, and a bifurcation from transient chaos to chaos is discussed. [Copyright &y& Elsevier]

Summary: Entrainment of the Drosophila circadian clock to light involves the light-induced degradation of the clock protein timeless (TIM). We show here that this entrainment mechanism is inhibited by serotonin, acting through the Drosophila serotonin receptor 1B (d5-HT1B). d5-HT1B is expressed in clock neurons, and alterations of its levels affect molecular and behavioral responses of the clock to light. Effects of d5-HT1B are synergistic with a mutation in the circadian photoreceptor cryptochrome (CRY) and are mediated by SHAGGY (SGG), Drosophila glycogen synthase kinase 3β (GSK3β), which phosphorylates TIM. Levels of serotonin are decreased in flies maintained in extended constant darkness, suggesting that modulation of the clock by serotonin may vary under different environmental conditions. These data identify a molecular connection between serotonin signaling and the central clock component TIM and suggest a homeostatic mechanism for the regulation of circadian photosensitivity in Drosophila. [Copyright &y& Elsevier]

It is indispensable to remove CO at the level of less than 50 ppm in H2-rich feed gas for the proton exchange membrane (PEM) fuel cells. In this paper, catalyst with high activity and selectivity, and a microchannel reactor for CO preferential oxidation (PROX) have been developed. The results indicated that potassium on supported Rh metal catalysts had a promoting effect in the CO selective catalytic oxidation under H2-rich stream, and microchannel reactor has an excellent ability to use in on-board hydrogen generation system. CO conversion keeps at high levels even at a very high GHSV as 500 000 h-1, so, miniaturization of hydrogen generation system can be achieved by using the microchannel reactor. [Copyright &y& Elsevier]

A one-dimensional isothermal pseudo-homogeneous parallel flow model was developed for the methanol synthesis from CO2 in a silicone rubber/ceramic composite membrane reactor. The fourth-order Runge–Kutta method was adopted to simulate the process behaviors in the membrane reactor. How those parameters affect the reaction behaviors in the membrane reactor, such as Damko¨hler number Da, pressure ratio pr, reaction temperature T, membrane separation factor α, membrane permeation parameter Φ, as well as the non-uniform parameter of membrane permeation L1, were discussed in detail. Parts of the theoretical results were tested and verified; the experimental results showed that the conversion of the main reaction in the membrane reactor increased by 22% against traditional fixed bed reactor, and the optimal non-uniform parameter of membrane permeation rate, L1,opt, does exist. [Copyright &y& Elsevier]

This article reports a short and efficient synthesis of chiral dioxocyclens starting from natural amino acids. Four new chiral dioxocyclens that contain different substituents at the chiral center were obtained. These dioxocyclens could not only be used for chiral recognition, but provide a feasible way for the synthesis of chiral cyclens. [ABSTRACT FROM AUTHOR]

A novel cellulose membrane was prepared by using amine oxides as the solvent and its mechanical performance was measured. Steady-state permeation rates of carbon dioxide, hydrogen, methane, nitrogen, oxygen, argon and helium in the homogeneous dense cellulose membrane were measured in the temperature range of 298–353 K and under gas pressures up to 1 MPa. The effect of swelling on hydrophilic membrane permeability was studied in some detail on the cellulose membrane. The difference in gas permeability between the “dry” cellulose membrane and the “water-swollen” cellulose membrane was investigated, and the gas permeability between the cellulose membrane and the Cellophane was compared. In this paper, the separation performance of CO2 over H2 in a “water-swollen” cellulose membrane is reported for the first time and the separation factor of CO2/H2 can be up to 15. [Copyright &y& Elsevier]

The AMSAA-BISE model is derived from another approach. This certainly shows the correctness of the AMSAA-BISE model, and indicates the incorrectness of the approximate model given in this paper. The engineering example illustrating these conclusions is given. Merits and demerits of AMSAA and AMSAA-BISE model are discussed. [ABSTRACT FROM AUTHOR]

The AMSAA-BISE model is derived from another approach. This certainly shows the correctness of the AMSAA-BISE model, and indicates the incorrectness of the approximate model given in this paper. The engineering example illustrating these conclusions is given. Merits and demerits of AMSAA and AMSAA-BISE model are discussed. [ABSTRACT FROM AUTHOR]

Presents information on a study which investigated the extent to which lipopolysaccharide (LPS) affects endotoxin-induced tumor necrosis factor (TNF)-alpha production. Comparison of the amount of TNF-alpha produced by various transduced macrophages; Materials and methods of the study; Results and discussion.

BACKGROUND RESULTS CONCLUSION Dendrobium officinale flos (DOF), a novel food raw material, is used in Chinese folk medicine to nourish the stomach. However, there is still no available study to evaluate the effects of DOF on animal models of acute gastric injury and its mechanism by modern pharmacological research.Herein, we characterized the major components of an aqueous extract of DOF and assessed its potential ameliorative effects in a rat model of acute gastric mucosal injury. The DOF water extract showed significant protective effects on the gastric mucosa and exhibited excellent antioxidant and anti‐inflammatory activities. Acute gastric injury rat models induced by ethanol (6 mL kg−1) were pretreated with different doses of DOF water extract (50–100 mg kg−1 day−1), and the biological effects of DOF extract in gastric tissues were evaluated. DOF extract alleviated the symptoms of ethanol‐stimulated acute gastric mucosal injury, as evidenced by a significant reduction in gastric injury index and the degree of gastric pathological changes. Additionally, treatment with DOF extract upregulated mucin expression in the gastric mucosa, attenuated oxidative stress, decreased the release of inflammatory mediators (TNF‐α, IL‐6), suppressed the expression of key proinflammatory enzymes (COX‐2 and iNOS), reduced the phosphorylation of p38 MAPK and p65 NF‐κB and increased the level of PGE2 in gastric tissues.DOF exerts protective effects against ethanol‐induced acute gastric mucosal injury, mainly by inhibiting inflammation and oxidative stress. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Optical encryption technologies based on persistent luminescence material have currently drawn increasing attention due to the distinctive and long‐lived optical properties, which enable multi‐dimensional and dynamic optical information encryption to improve the security level. However, the controlled synthesis of persistent phosphors remains largely unexplored and it is still a great challenge to regulate the structure for optical properties optimization, which inevitably sets significant limitations on the practical application of persistent luminescent materials. Herein, a controlled synthesis method is proposed based on defect structure regulation and a series of porous persistent phosphors is obtained with different luminous intensities, lifetime, and wavelengths. By simply using diverse templates during the sol–gel process, the oxygen vacancy defects structures are successfully regulated to improve the optical properties. Additionally, the obtained series of porous Al2O3 are utilized for multi‐color and dynamic optical information encryption to increase the security level. Overall, the proposed defect regulation strategy in this work is expected to provide a general and facile method for optimizing the optical properties of persistent luminescent materials, paving new ways for broadening their applications in multi‐dimensional and dynamic information encryption. [ABSTRACT FROM AUTHOR]

Multi‐dimensional force sensing that combines intensity, location, area and the like could gather a wealth of information from mechanical stimuli. Developing materials with force‐induced optical and electrical dual responses would provide unique opportunities to multi‐dimensional force sensing, with electrical signals quantifying the force amplitude and the luminescence output providing spatial distribution of force. However, the reliance on external power supply and high‐energy excitation source brings significant challenges to the applicability of multi‐dimensional force sensors. Here we reported the mechanical energy‐driven and sunlight‐activated materials with force‐induced dual responses, and investigated the underlying mechanisms of self‐sustainable force sensing. Theoretical analysis and experimental data unraveled that trap‐controlled luminescence and interfacial electron transfer play a major role in force‐induced optical and electrical output. These materials were manufactured into pressure sensor with renewable dual‐mode output for quantifying and visualization of pressures by electrical and optical output, respectively, without power supply and high‐energy irradiation. The quantification of tactile sensation and stimuli localization of mice highlighted the multi‐dimensional sensing ability of the sensor. Overall, this self‐powered pressure sensor with multimodal output provides more modalities of force sensing, poised to change the way that intelligent devices sense with the world. [ABSTRACT FROM AUTHOR]

Multi‐dimensional force sensing that combines intensity, location, area and the like could gather a wealth of information from mechanical stimuli. Developing materials with force‐induced optical and electrical dual responses would provide unique opportunities to multi‐dimensional force sensing, with electrical signals quantifying the force amplitude and the luminescence output providing spatial distribution of force. However, the reliance on external power supply and high‐energy excitation source brings significant challenges to the applicability of multi‐dimensional force sensors. Here we reported the mechanical energy‐driven and sunlight‐activated materials with force‐induced dual responses, and investigated the underlying mechanisms of self‐sustainable force sensing. Theoretical analysis and experimental data unraveled that trap‐controlled luminescence and interfacial electron transfer play a major role in force‐induced optical and electrical output. These materials were manufactured into pressure sensor with renewable dual‐mode output for quantifying and visualization of pressures by electrical and optical output, respectively, without power supply and high‐energy irradiation. The quantification of tactile sensation and stimuli localization of mice highlighted the multi‐dimensional sensing ability of the sensor. Overall, this self‐powered pressure sensor with multimodal output provides more modalities of force sensing, poised to change the way that intelligent devices sense with the world. [ABSTRACT FROM AUTHOR]

The decline of bus ridership is increasingly prevalent in cities in both developed and emerging economies around the world. While researchers have made many efforts to explain why choice riders switch to other transportation modes in single-city cases, why cities vary in the performance of maintaining bus ridership is still largely unknown. This study examines the changes in bus ridership among 175 medium and small-sized cities without urban rail transit from 2010 to 2019 in China and links a few determining factors to such changes by deploying fixed effects panel models and piecewise regression models. Both heterogeneity and nonlinear relationships in the dynamics of bus ridership changes are confirmed. The results demonstrate that cities at different development stages perform diversely in maintaining bus ridership, due to the variations in travel demand and travel choice preferences in those contexts. Increased private car ownership and widening income inequity both contribute to bus ridership decline while an expansion of bus fleet sizes is associated with more bus patronage. These relationships are all displayed as nonlinear formats; the effects can diminish when influencing factors reach a certain level during the growth of cities. The research outcomes may inform policymakers that cities at different development stages need to adopt context-based strategies instead of simply copying from elsewhere. Policies such as controlling private car ownership might not work equally well in cities with diversified characteristics. • Shed light on the bus ridership decline challenges faced by 175 medium and small-sized cities in China. • Explore the interaction and nonlinear effect from influencing factors on bus ridership. • Focus on medium and small-sized cities' bus ridership decline phenomenon. • Emphasize the importance of understanding city-specific dynamics to formulate effective transit strategies. [ABSTRACT FROM AUTHOR]

Functionally graded materials (FGMs) are a novel class of composite materials that have attracted significant attention in the field of engineering due to their unique mechanical properties. This study aims to explore the dynamic behaviors of an FGM stepped beam with different boundary conditions based on an efficient solving method. Under the assumptions of the Euler-Bernoulli beam theory, the governing differential equations of an individual FGM beam are derived with Hamilton's principle and decoupled via the separation-of-variable approach. Then, the free and forced vibrations of the FGM stepped beam are solved with the transfer matrix method (TMM). Two models, i.e., a three-level FGM stepped beam and a five-level FGM stepped beam, are considered, and their natural frequencies and mode shapes are presented. To demonstrate the validity of the method in this paper, the simulation results by ABAQUS are also given. On this basis, the detailed parametric analyses on the frequencies and dynamic responses of the three-level FGM stepped beam are carried out. The results show the accuracy and efficiency of the TMM. [ABSTRACT FROM AUTHOR]

HBV expresses more than 10 spliced RNAs from the viral pregenomic RNA, but their functions remain elusive and controversial. To address the function of HBV spliced RNAs, we generated splicing-deficient HBV mutants and conducted experiments to assess the impact of these mutants on HBV infection. HepG2-NTCP cells, human hepatocyte chimeric FRG mice (hu-FRG mice), and serum from patients with chronic hepatitis B were used for experiments on HBV infection. Additionally, SHifter assays and cryo-electron microscopy were performed. We found the infectivity of splicing-deficient HBV was decreased 100-1,000-fold compared with that of wild-type HBV in hu-FRG mice. Another mutant, A487C, which loses the most abundant spliced RNA (SP1), also exhibits severely impaired infectivity. SP1 hypothetically encodes a novel protein HBcSP1 (HBc-Cys) that lacks the C-terminal cysteine from full-length HBc. In the SHifter assay, HBcSP1 was detected in wild-type viral particles at a ratio of about 20-100% vs. conventional HBc, as well as in the serum of patients with chronic hepatitis B, but not in A487C particles. When infection was conducted with a shorter incubation time of 4-8 h at lower PEG concentrations in HepG2-NTCP cells, the entry of the A487C mutant was significantly slower. SP1 cDNA complementation of the A487C mutant succeeded in rescuing its infectivity in hu-FRG mice and HepG2-NTCP cells. Moreover, cryo-electron microscopy revealed a disulfide bond between HBc cysteine 183 and 48 in the HBc intradimer of the A487C capsid, leading to a locked conformation that disfavored viral entry in contrast to the wild-type capsid. Prior studies unveiled the potential integration of the HBc-Cys protein into the HBV capsid. We confirmed the proposal and validated its identity and function during infection. HBV SP1 RNA encodes a novel HBc protein (HBcSP1) that lacks the C-terminal cysteine from conventional HBc (HBc-Cys). HBcSP1 was detected in cell culture-derived HBV and confirmed in patients with chronic infection by both immunological and chemical modification assays at 10-50% of capsid. The splicing-deficient mutant HBV (A487C) impaired infectivity in human hepatocyte chimeric mice and viral entry in the HepG2-NTCP cell line. Furthermore, these deficiencies of the splicing-deficient mutant could be rescued by complementation with the SP1-encoded protein HBcSP1. We confirmed and validated the identity and function of HBcSP1 during infection, building on the current model of HBV particles. [Display omitted] • The infectivity of splicing-deficient HBV was significantly decreased compared to WT HBV in hu-FRG mice. • SP1 RNA encodes HBcSP1, which is found in 10 to 50% of nucleocapsids in patients with CHB and cell line-derived WT HBV. • The splicing-deficient mutant A487C, lacking HBcSP1, reduces the efficiency of viral entry kinetics. • Disulfide bonds between Cys48 and Cys183 in the A487C capsid led to a locked conformation that disfavored viral entry. [ABSTRACT FROM AUTHOR]

All-silicon terahertz absorbers have attracted considerable interest. We present a design and numerical study of an all-silicon polarization-insensitive terahertz metamaterial absorber. The meta-atoms of the metamaterial absorber are square silicon rings which can be viewed as gratings. By properly optimizing the structure of the meta-atom, we achieve a broadband absorptivity that is above 90% ranging from 0.77 THz to 2.53 THz, with a relative bandwidth of 106.7%. Impedance matching reduces the reflection of the terahertz waves and the (0, ±1)-order diffraction induce the strong absorption. The absorption of this absorber is insensitive to the polarization of the terahertz wave and has a large incident angle tolerance of up to 60 degrees. The all-silicon metamaterial absorber proposed here provides an effective way to obtain broadband absorption in the terahertz regime. Metamaterial absorbers have outstanding applications in terahertz communication and imaging. [ABSTRACT FROM AUTHOR]

Bacterial species within the Acinetobacter baumannii-calcoaceticus (Acb) complex are very similar and are difficult to discriminate. Misidentification of these species in human infection may lead to severe consequences in clinical settings. Therefore, it is important to accurately discriminate these pathogens within the Acb complex. Raman spectroscopy is a simple method that has been widely studied for bacterial identification with high similarities. In this study, we combined surfaced-enhanced Raman spectroscopy (SERS) with a set of machine learning algorithms for identifying species within the Acb complex. According to the results, the support vector machine (SVM) model achieved the best prediction accuracy at 98.33% with a fivefold cross-validation rate of 96.73%. Taken together, this study confirms that the SERS-SVM method provides a convenient way to discriminate between A. baumannii, Acinetobacter pittii, and Acinetobacter nosocomialis in the Acb complex, which shows an application potential for species identification of Acinetobacter baumannii-calcoaceticus complex in clinical settings in near future. [ABSTRACT FROM AUTHOR]