Search

A high-peak-power (several hundreds of watts) pulsed CO2 laser, recently developed in our laboratory, has been used for exciting optically pumped far-infrared laser transitions of N2H4, A systematic search for N2H4 absorption coincidences with 10P and 10HP CO2 laser emissions has led to the observation of 27 new fir-infrared laser lines, excited by 18 different absorption transitions. All of these new lines have been characterized in wavelength, offset, relative polarization, optimum operation pressure and intensity. Using the LaseRitz program, ten of these lines were assigned, corresponding to five laser systems. For other two laser systems possible J and K quantum numbers of the energy levels involved in the laser transitions were given. [ABSTRACT FROM AUTHOR]

In this paper, we present an existence theorem of almost periodic solutions of second-order neutral delay–differential equations with piecewise constant arguments of the form (x(t)+x(t-1))″=qx([t])+f(t), where [·] denotes the greatest integer function, q is a nonzero constant, and f(t) is almost periodic. [Copyright &y& Elsevier]

This work reports dual-mode operation of a broadly tunable CO[sub 2]-laser/microwave-sideband spectrometer employing a Cheo waveguide modulator and a CO[sub 2] laser that can operate on hot and sequence band lines as well as low- and high-J regular band lines. The spectrometer has a broadband scanning mode at Doppler-limited resolution for spectral searching and assignment, and a narrow-band sub-Doppler mode for precision measurements. In broadband mode, a 6.7–18.5 GHz (∼0.4 cm[sup -1]) window can be covered for each sideband in a single microwave sweep with a tracking Fabry–Perot etalon filter under computer control. In sub-Doppler mode, saturation-dip spectra are obtained at sub-MHz resolution with absolute frequency measurement accuracy of the order of ±200 kHz. The instrumental performance is demonstrated via spectra of the C–O stretching fundamental vibrational band of methanol. Doppler-limited broadband scans have been recorded with good signal-to-noise ratio in both the low- and high-J regions of the 9.6-μm-CO[sub 2] laser band, while narrow-band sub-Doppler scans have permitted clean separation of very close-lying lines in the CH[sub 3]OH spectrum. The measurement precision is confirmed for several CH[sub 3]OH transition systems through closure of combination loops. Our results illustrate the wide coverage and excellent resolution obtainable with CO[sub 2]-sideband infrared laser radiation in a broadly tunable and convenient infrared source with high potential for spectroscopic applications. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

An ab initio investigation of the OH-stretching overtone of methanol is presented aimed at interpretation of two of the interesting features reported in recent supersonic-jet infrared-laser-assisted photofragment spectroscopy (IRLAPS) studies, namely, (i) a monotonic decrease of the torsional E – A splitting as υ[sub OH] increases, (ii) an evolution of the a-type transition moment towards dominance at higher excitations of the OH-stretching vibration. At the MP2 level with a 6-311+G(3df,2p) basis set, one-dimensional functions for the potential energy, dipole moment (a and b directions), barrier height V[sub 3] , and torsional constant F have been mapped out as a function of the OH-bond length with the remaining structure relaxed. All ab initio quantities have been expressed as Taylor-series expansions in the dimensionless OH normal coordinate, q. Calculations have been carried out in the harmonic basis set to yield vibrational energies and eigenfunctions. The latter have been used to evaluate the torsional parameters (V[sub 3] , F) and the resulting E – A torsional splittings at each OH excitation, and to compute the evolution of the infrared transition intensity ratio [sub a/b] . The ab initio results reproduce the reported decrease in E – A splitting by a factor of 5 in going from υ[sub OH] = 0 to υ[sub OH] = 6, with a maximum deviation of 19% at the highest excitation. The calculated variation in [sub a/b] is in qualitative agreement with the experimental trend, showing the observed sharp rise at high υ[sub OH] . PACS Nos.: 33.20E, 33.80BNous avons fait une étude complète de l'étirement OH dans le méthanol afin d'améliorer l'interprétation de deux des caractéristiques les plus intéressantes récemment rapportées dans des mesures utilisant un jet supersonique et la spectroscopie de photo-fragmentation induite par laser (IRLAPS). Nous étudions plus précisément (i) la décroissance monotone de la séparation E – A lorsque υ[sub OH] augmente, (ii) une tendance du moment de transition de type a à dominer à plus haute excitation vibrationnelle de l'étirement OH. Au niveau MP2, avec un ensemble de base 6-311+G(3df,2p), les fonctions unidimensionnelles pour l'énergie potentielle, le moment dipolaire (directions a et b), la hauteur de barrière V[sub 3] et la constante de torsion F ont été tracées en fonction de la longueur du lien OH, tout en négligeant les autres éléments de structure. Toutes les quantités résultant du calcul complet ont été exprimées en série de Taylor dans la coordonnée normale sans dimension de OH, q. Les calculs ont été faits dans la base harmonique pour obtenir les énergies de vibration et les fonctions propres. Ces dernières ont permis d'évaluer les paramètres de torsion (V[sub 3] , F) et la séparation résultant de la torsion E – A à chaque excitation OH, ainsi que de mesurer l'évolution du rapport d'intensité de transition infrarouge [sub a/b] . Ces calculs reproduisent l'observation d'une décroissance par un facteur 5 de la séparation E – A en allant de υ[sub OH] = 0 à υ[sub OH] = 6, avec une déviation maximale de 19% à la plus haute énergie d'excitation. Le calcul de [sub a/b] est en accord qualitatif avec la tendance expérimentale, montrant un accroissement rapide aux hautes valeurs de υ[sub OH] .[Traduit par la Rédaction] [ABSTRACT FROM AUTHOR]

The high-resolution Fourier transform spectrum of CH[sub 3] OH has been investigated in the 1400–1650 cm[sup –1] CH[sub 3] -bending region, and perpendicular DK = 1 subbands forming a consistent pattern have been identified with origins from 1490 to 1570 cm[sup –1] . The location of the subbands as the only significant spectral features towards the upper edge of the CH[sub 3] -bending absorption favours their assignment to the ν[sub 4] in-plane A' asymmetric CH[sub 3] -bending mode. The upper state term values have been fitted to J(J + 1) power-series expansions to obtain substate origins and effective B-values. The origins exhibit a linear K-dependence as well as the normal variation with K[sup 2] . The mean effective B-value of 0.82 cm[sup –1] is higher than that of the ground state, consistent with a bending vibration. The pattern of K-reduced torsion–vibration energies is anomalous. It appears to be inverted relative to the customary picture for n = 0 torsional levels, in agreement with a recent prediction, but has unusual periodicity significantly different from the ground state. A simple Fourier cosine series model for the energy curves gives a vibrational band origin of 1477.6 cm[sup –1] for this CH[sub 3] -bending mode, close to the best current calculated value for ν[sub 4] . PACS Nos.: 33.20E, 33.80BNous étudions le spectre à transformée de Fourier de haute résolution du CH[sub 3] OH dans la région 1400–1650 cm[sup –1] de flexion du CH[sub 3] et identifions des sous-bandes perpendiculaires Δ K = 1, avec des origines allant de 1490 à 1570 cm[sup –1] . Le fait que les sous-bandes constituent le seul élément significatif de la tranche supérieure du spectre dû à la flexion du CH[sub 3] suggère qu'on les assigne au mode ν[sub 4] planaire asymétrique A' de flexion du CH[sub 3] . Nous ajustons à une série de puissance en J(J + 1) les termes des états supérieurs pour obtenir l'origine des sous-états et les valeurs efficaces des coefficients B. Les origines ont une dépendance linéaire en K, aussi bien que que l'habituelle dépendance en K[sup 2] . La valeur moyenne efficace de B = 0,82 cm[sup –1] est plus élevée que celle du fondamental, ce qui est cohérent avec une vibration de flexion. La structure des niveaux de vibration–torsion est anomale. Elle semble inversée par rapport à l'image habituelle pour les niveaux de torsion n = 0, en accord avec de récentes prédictions, mais avec une périodicité inattendue significativement différente de celle du fondamental. Une simple analyse de Fourier en cosinus pour les courbes d'énergie donne une origine de la bande de vibration à 1477,6 cm[sup –1] pour ce mode de flexion CH3, proche de la meilleure valeur calculée pour ν[sub 4] . [Traduit par la Rédaction] [ABSTRACT FROM AUTHOR]

Three undescribed bicyclo[3.2.1]octanoid neolignan glucosides, along with a known neolignan, were isolated from the leaves of Piper crocatum Ruiz & Pav. Their chemical structures were elucidated using extensive spectroscopic analyses including 1D and 2D NMR experiments and HR-ESI-MS analysis, as well as through comparison with previously reported data. Two compounds were assessed for their inhibitory effect against pyruvate dehydrogenase E1α S300 phosphorylation. The fluorescent image suggested that both compounds (60 µM) revealed a stronger inhibition effect than the positive control (dichloroacetate, DCA 5 mM), with IC50 values of 99.82 µM and 80.25 µM, respectively. [ABSTRACT FROM AUTHOR]

Ultraviolet (UV) light trapping by monolayer graphene is of great significance in optoelectronic devices. In this work, to enhance the UV absorption of monolayer graphene, a metallic thin film-type/graphene/Bragg mirror optical structure is developed using transfer matrix methods. Our results showed that the absolute UV absorption of monolayer graphene can reach approximately 83 % at the wavelength of 270 nm, which is a 9.2-fold enhancement compared to the intrinsic value of free-standing graphene (9%). This high absorption is due to the strong field confinement of the Tamm state in the silica spacer layer. The UV absorption of graphene can be tuned by adjusting the nanostructure parameters and incident angles. Furthermore, the proposed structure is less affected by machining errors. Considering the influence of processing precision, the light absorption of graphene in this structure is higher than that in the microcavity of a photonic crystal. The results obtained in this study may find promising applications in high-performance UV–graphene optoelectronic devices, such as modulators and photodetectors, as well as in photocatalysis. [ABSTRACT FROM AUTHOR]

This study identified three coumarins (1–3), and six moracin derivatives (4–9). The structures of these natural compounds were determined by the spectroscopic methods, including 1D and 2D NMR methods, and comparison with previous reported data. All of the isolated compounds were assessed for the effects on the soluble epoxide hydrolase (sEH) inhibitory activity. Among them, compounds 1–7 exhibited significant inhibitory effect with 100% inhibitory, with IC50 values of 6.9, 0.2, 15.9, 1.1, 1.2, 9.9, and 7.7 µM, respectively. A kinetic study revealed that compounds 1–4, and 6 were competitive types of inhibitors, compounds 5 and 7 were mixed types of inhibitors. These results suggest that moracin and coumarin derivatives from mulberry leaves are significant sEH inhibitors. [ABSTRACT FROM AUTHOR]

The torsional dependence of the CH[sub 3] stretching and bending modes of methanol has been explored in terms of a local mode internal coordinate picture [X. Wang and D. S. Perry, J. Chem. Phys. 109, 10795 (1998)]. First, the torsional variations of the small-amplitude vibrational frequencies along the mass weighted intrinsic reaction coordinate from the top to the bottom of the torsional potential barrier were calculated by means of ab initio frequency projection utilizing GAUSSIAN 98. The resulting curves for the three C-H stretch ab initio frequencies as functions of the torsional angle cannot be reproduced by the original 3x3 local mode model incorporating stretch-torsion and stretch-stretch couplings at lowest-order only, but are well-fitted if the model is extended to include higher-order coupling terms. For the CH-bending modes, with internal coordinates chosen to give a high degree of localization, bend-torsion and bend-bend coupling parameters were determined from the ab initio projected frequencies, and were then used to predict torsional tunneling splittings. Just as observed for the C-H stretch modes, the two higher-frequency asymmetric CH-bend modes are predicted to have inverted tunneling splittings with reduced amplitudes, while the splitting pattern for the lower frequency symmetric-bend mode is predicted to be normal. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The phytochemical investigation of Dendropanax morbiferus H. Lév. Led to the isolation of 28 known compounds: 4 alkaloids (1 – 4), 1 pyranoglucoside (5), 1 benzoic acid and 5 benzoic acid derivatives (6 – 11), 10 phenylpropanoids (12 – 21), 4 flavone glucoside derivatives (22 – 25), 1 neolignan (26) and 2 sesquiterpenes (27 – 28). The structures of these compounds were identified using spectroscopic methods; their nuclear magnetic resonance spectra were compared with those previously reported. This is the first report on compounds 2 – 4 , 10 , and 12 isolated from D. morbiferus. Compounds 5 and 26 from the genus Dendropanax and 1 , 6 – 9 , 11 , 13 , 14 – 25 , 27 and 28 from the family Araliaceae were isolated for the first time. Additionally, to the best of our knowledge, this is the first comprehensive chemical investigation of D. morbiferus stems and leaf compounds. Chemotaxonomic relationship between D. morbiferus and other Dendropanax species is also discussed. Image 1 • Totally 28 compounds were isolated from Dendropanax morbiferus. • 5 compounds were first time report from Dendropanax morbiferus. • 2 compounds were first time report from genus Dendropanax. • 21 compounds were first time report from family Araliaceae. • This is the first comprehensive chemical investigation of D. morbiferus. [ABSTRACT FROM AUTHOR]

Chemical study of Piper crocatum leaves has led to isolation of a new megastigmane glucoside isomer (18), along with 23 known compounds including fifteen phenolic compounds (1 – 15), two monoterpenes (16 and 17), three sesquiterpenes (19 – 21), a phenolic amide glycoside (22), a neolignan (23), and a flavonoid C-glycoside (24). Structures of these compounds were identified via spectroscopic methods and compared with those reported in the literature. Seven compounds (7 , 11 , 13 , 14 , 17 , 20 , and 24) from the P. crocatum species and 17 others (1 – 6 , 8 – 10 , 12 , 15 – 16, 18 – 19 , and 21 – 23) from the Piper genus and Piperaceae family were isolated and reported for the first time. Furthermore, this study discusses chemotaxonomic relations between P. crocatum and other Piper species. Image 1 • One new a new megastigmane glucoside isomer was isolated. • Totally 24 compounds were isolated from Piper crocatum leaves. • 7 compounds were first isolated from Piper crocatum. • 14 compounds were first isolated from the Piper genus and Piperaceae family. [ABSTRACT FROM AUTHOR]

Two new phenolic glucosides, pipercroside A and B (1 and 2), along with 10 known compounds were isolated from the leaves of Piper crocatum Ruiz & Pav. Their chemical structures were elucidated through extensive spectroscopic analyses, including 1D and 2D NMR experiments and HR-ESI-MS analysis and comparison with previously reported data. All the isolated compounds were assessed for soluble epoxide hydrolase (sEH) inhibitory activity. Among them, erigeside II (5) showed inhibitory activity with an IC50 value of 58.5 µM. [ABSTRACT FROM AUTHOR]

By using Bochner transform, Stepanov almost periodic functions inherit some basic properties directly from almost periodic functions. Recently, this old work was extended to time scales. However, we show that Bochner transform is not valid on time scales. Then we present a revised version, called Bochner-like transform, for time scales, and prove that a function is Stepanov almost periodic if and only if its Bochner-like transform is almost periodic on time scales. Some basic properties including the composition theorem of Stepanov almost periodic functions are obtained by applying Bochner-like transform. Our results correct the recent results where Bochner transform is used on time scales. As an application, we give some results on dynamic equations with Stepanov almost periodic terms. [ABSTRACT FROM AUTHOR]

The individual parts of Morus alba L. including root bark, branches, leaves, and fruits are used as a cosmetic ingredient in many Asian countries. This study identified several anti-melanogenesis constituents in a 70% ethanol extract of M. alba leaves. The ethyl acetate fraction of the initial ethanol extract decreased the activity of tyrosinase, a key enzyme in the synthetic pathway of melanin. Twelve compounds were isolated from this fraction and their structures were identified based on spectroscopic spectra. Then, the authors investigated the anti-melanogenesis effects of the isolated compounds in B16-F10 mouse melanoma cells. Compounds 3 and 8 significantly inhibited not only melanin production but also intracellular tyrosinase activity in alpha-melanocyte-stimulating-hormone (α-MSH)-induced B16-F10 cells in a dose-dependent manner. These same compounds also inhibited melanogenesis-related protein expression such as microphthalmia-associated transcription factor (MITF), tyrosinase, and tyrosinase-related protein-1 (TRP-1). Compound 3 modulated the cAMP-responsive element-binding protein (CREB) and p38 signaling pathways in α-MSH-activated B16-F10 melanoma cells, which resulted in the anti-melanogenesis effects. These results suggest that compound 3, isolated from M. alba leaves, could be used to inhibit melanin production via the regulation of melanogenesis-related protein expression. [ABSTRACT FROM AUTHOR]

It is well known that many important properties of μ-pseudo almost automorphic (periodic) functions are based on the translation invariance. In this paper we give a new result of the translation invariance with conditions weaker than the known one. Then some more properties are studied, including the uniqueness of the decomposition and the convolution of the space. Moreover, we present a result on the equality of two spaces of this kind of functions, which extends the well-known results to the case when the measures of the spaces are not equivalent. As an application, we give an existence and uniqueness theorem of μ-pseudo almost automorphic mild solution for a semilinear fractional differential equation. [ABSTRACT FROM AUTHOR]

We report saturation dip spectroscopy in the C–N stretching band of CH3NH2 with a resolution of 0.4 MHz and an accuracy of 0.1 MHz by use of a CO2-laser/microwave-sideband spectrometer. The wide tunability, Lamb-dip resolution, absolute frequency accuracy, and high sensitivity of our dual-mode instrument were all key features in making precise measurements for a range of lines in the densely crowded spectrum with its complex pattern of splittings arising from the large-amplitude CH3 torsion and NH2 inversion. We focused on achieving resolution and assignment of transitions within the highly blended Q branch of the C–N stretch and on observations of the important K=0 sequences of Aa and Ea torsion-inversion symmetry. Term values of the latter were fitted to J(J+1) power-series expansions to obtain the K=0 C–N stretching effective B values and substate origins, from which calculated ground-state substate energies were subtracted to yield values of 1044.7061 and 1044.8011 cm-1 for the Aa and Ea subband origins, respectively. We thereby estimate a mean value of 1044.75(5) cm-1 for the vibrational band origin and 0.7323(5) cm-1 for the effective upper-state B value for the C–N stretching fundamental of CH3NH2. [ABSTRACT FROM AUTHOR]

Our aim in the article is to study the existence of μ-pseudo almost automorph mild solutions to the following fractional integro-differential equation: Dαu(t)=Au(t)+∫−∞ta(t−s)Au(s)ds+f(t,u(t)),t∈R, where for α>0, the fractional derivative Dα is understood in the sense of Weyl, and A is a closed linear operator defined on Banach space X, a∈Lloc1(R+) is a scalar-valued kernel. The novelty of this work is a study of this equation with a μ-Sp-pseudo almost automorph nonlinear term satisfying the condition of “uniform continuity” instead of some “Lipschitz” type conditions supposed in the literature. We utilize Schauder’s fixed point theorem. An example is provided to explain our abstract results. [ABSTRACT FROM AUTHOR]

Sanguisorba officinalis L. was well known as a traditional herbal medicine to treat inflammation and allergic skin diseases. The aim of this research was to indentify compounds with anti-allergic inflammatory property. Twenty-five compounds ( 1 – 25 ) were isolated from S. officinalis including two new compounds ( 1 and 8 ), and their chemical structures were identified by NMR and ESIMS analysis. Consequently, the anti-allergic inflammatory activities of these isolates were investigated by inhibiting β-hexosaminidase and IL-4 production in PMA/A23187-stimulated RBL-2H3 cells. Compounds 6 , 8 , 13 , 17 – 18 and 25 significantly inhibited β-hexosaminidase release and IL-4 production. Additionally, compounds 8 , 17 and 25 effectively suppressed the activation of NF-κB and NF-κB p65 translocation into the nucleus. Anti-inflammatory effects of isolated compounds were evaluated in LPS-stimulated RAW264.7 macrophages, and they showed dramatic inhibition on LPS-induced overproduction of nitric oxide (NO) and TNF-α. Consistently, the protein levels of iNOS and COX-2 were remarkably decreased by the single compounds 8 , 13 and 25 . These results showed that compounds 8 , 13 and 25 from S. officinalis may have a therapeutic potential for allergic inflammatory diseases. [ABSTRACT FROM AUTHOR]

It is well known that a sufficient and necessary condition for a continuous function gg to be almost periodic on time scale T{\mathbb{T}} is the existence of an almost periodic function ff on R{\mathbb{R}} such that ff is an extension of gg. The purpose of this article is to extend these results to Sp{S}^{p}-almost periodic functions. We prove that the necessity is true, that is, an Sp{S}^{p}-almost periodic function on T{\mathbb{T}} can be extended to an Sp{S}^{p}-almost periodic function on R{\mathbb{R}}. However, a counterexample is given to show that the sufficiency is not true in general. By introducing a concept of minor translation set and characterizing the almost periodicity on T{\mathbb{T}} in terms of this new concept, we obtain a condition to ensure the sufficiency. Moreover, we show the necessity of this condition by a counterexample.

In this paper, we propose a multi-group SEIR epidemic model with spatial diffusion, where the model parameters are spatially heterogeneous. The positivity and ultimate boundedness of the solution, as well as the existence of a global attractor of the associated solution semiflow, are established. The definition of the basic reproduction number is given by utilizing the next generation operator approach, whereby threshold-type results on the global dynamics in terms of this number are established. That is, when the basic reproduction number is less than one, the disease-free steady state is globally asymptotically stable, while if it is greater than one, uniform persistence of this model is proved. Finally, the feasibility of the main theoretical results is shown with the aid of numerical examples for a model with two groups.

In this paper, we study the following modified Kirchhoff-type equations of the form: [ABSTRACT FROM AUTHOR]

• Two novel monoterpene glycosides (1 – 2), together with 32 known compounds (3 – 34) were isolated from Aster tataricus. • Some compounds remarkably suppressed NO secretion in LPS-activated RAW264.7 cells. • Compound 7 exhibited a potential anti-inflammatory activity via inhibition of NF-κB and MAPKs activation. Aster tataricus L.f. is a traditional Eastern Asian herbal medicine used for the relief of cough-related illnesses. In this study, 32 known compounds and two novel monoterpene glycosides were isolated from the roots of A. tataricus. With the aid of reported data, elucidation of the root-extract components was carried out using a multitude of spectroscopic techniques. All isolates were investigated for their ability to inhibit nitric oxide (NO) secretion in lipopolysaccharide-activated RAW264.7 cells. Compound 7 remarkably suppressed NO production with an IC 50 value of 8.5 µM. In addition, compound 7 exhibited significant inhibitory activity against the production of inflammatory cytokines (prostaglandin E 2 , interleukin-6, and interleukin-1 beta) and the expression of inflammatory enzymes (inducible nitric oxide synthase and cyclooxygenase-2) via inhibition of nuclear factor-kappa B activation. Moreover, compound 7 effectively prevented the downstream activation of the mitogen-activated protein kinase signaling pathway by inhibiting phosphorylation of c-Jun N -terminal kinases, extracellular signal-regulated kinases, and p38. These results outline compound 7 as a potential inhibitor for the broad treatment of inflammatory diseases, such as atopic dermatitis, asthma, and various allergies. [ABSTRACT FROM AUTHOR]

To study the effects of ethylene oxide (EO) number in alkyl ethoxy carboxylates (AEC) on scale inhibition, ten AEC compounds are prepared. The effect of EO number on the scale inhibition against CaCO 3 , CaSO 4 and Ca 3 (PO 4 ) 2 scales and effects of the operating conditions on scale inhibition against CaCO 3 are investigated by static test. The effect of EO number on the corrosion inhibition is measured by the weight loss of rotating hung steel slices. The influence of AEC on formation of CaCO 3 , CaSO 4 and Ca 3 (PO 4 ) 2 is investigated using scanning electronic microscopy (SEM). The results indicate that the scale inhibition of AEC depends actually on EO number, the scale inhibition against CaCO 3 and Ca 3 (PO 4 ) 2 scales decreases with increasing EO number. The ability of the inhibitors to tolerate high alkalinity and high hardness reduces with increasing EO number. AEC-3, AEC-4 and AEC-5 have good performance with scale inhibition more than 80% at the pH, concentration of calcium carbonate and temperature ranges of 7.0–9.0, 250–750 mg/L and 50–80 °C, respectively. Morphologies of the scales are highly modified in the presence of AEC. The corrosion inhibition of AEC shows a significant critical threshold regarding the concentration of AEC, the corrosion inhibition increases with increasing EO number. [ABSTRACT FROM AUTHOR]

This paper presents a review of the previous studies and papers about various thermodynamic cycles working for high temperature power generation procedures, in these cycles the highest temperature is not lower than 700 K. Thermodynamic cycles that working for power generation are divided into two broad categories, thermodynamic cycle model study and working fluid analysis. Thermodynamic cycle contains the simple cycle model and the complex cycle model, emphasis has been given on the complex thermodynamic cycles due to their high thermal efficiencies. Working fluids used for high temperature thermodynamic cycles is a dense gas rather than a liquid. A suitable thermodynamic cycle is crucial for effectively power generation especially under the condition of high temperature. The main purpose is to find out the characteristics of various thermodynamic cycles when they are working in the high temperature region for power generation. As this study shows, combined cycles with both renewable and nonrenewable energies as the heat source can show good performance. [ABSTRACT FROM AUTHOR]

Unordered tree is widely used for semi-structured data modeling, coverage pattern mining on it has benefit for finding frequent subtrees without redundant information, so that improve the efficiency of subsequent knowledge discovering. A coverage pattern mining method MCRP is proposed. Firstly, all candidate subtrees are generated on the basis of maximum prefix coding and edge extension.Then coverage patterns are output by introducing δ′- coverage concept. Compared with traditional algorithms such as mining frequent closed tree patterns and maximal frequent tree patterns, the proposed method can output fewer frequent subtrees in the case of preserving all the frequent subtree information, and has a certain superiority in processing efficiency.

Tiger puffer fish (Takifugu rubripes)is one of the most economically valuable aquaculture species in Asia. However, farming tiger puffer fish at the juvenile stage has been greatly restrained by cannibalization caused by inappropriate feeding regimes, resulting in very high mortality and great economic loss, particularly in intensive recirculating aquaculture systems. Therefore, the feeding strategy should adapt to fish appetite, nutrition requirements and welfare in intensive aquaculture. A 60-day feeding experiment was conducted to evaluate the effects of feeding frequency on the overall health of juvenile tiger puffer fish. Fish were randomly assigned to four groups with different feeding frequencies using the same ration size per feeding. P1: two daily meals; P2: four daily meals; P3: six daily meals; P4: continuous diurnal feeding using a belt feeder. Fish in the P2 group exhibited optimal values for growth, including final weight, weight gain rate, specific growth rate, feed efficiency, and survival (P < 0.05), followed by those in the P3 group. The crude lipid content increased significantly with increasing feeding frequency (P < 0.05), indicating that high frequency feeding could accumulate higher body fat content. The apparent digestibility coefficients of dry matter, protein, and lipid were significantly lower for fish in the P4 group than for those in the other groups (P < 0.05). The total cholesterol, triglyceride, and glucose levels increased significantly with increasing feeding frequency (P < 0.05), indicating that high frequency feeding leads to excessive accumulation of dietary carbohydrates and lipids in juvenile tiger puffer fish. Fish in the P1 and P4 groups exhibited relatively higher antioxidant enzyme activities (P < 0.05), which suggested that low and high feeding frequencies cause oxidative stress in juvenile tiger puffer fish. A comparison of non-linear model parameters revealed that an exponential model best described the gastric evacuation rate of juvenile tiger puffer fish, with approximately half the meal passed within 3 h, which further confirmed that feeding intervals in four times/day may more closely align with the digestive physiological characteristics of juvenile tiger puffer fish. Overall, these results indicate that the best growth performance and physiological indicators can be achieved when fed at 4 times/day. • High frequency feeding causes carbohydrate and lipid accumulation in juvenile tiger puffer fish. • Low and high feeding frequencies had adverse effects for juvenile tiger puffer fish. • Variation in feeding frequency had no effect on GER, and approximately 50% of a single meal was passed within 3 h. • Optimal feeding frequency for cultured juvenile tiger puffer fish is four meals/day. [ABSTRACT FROM AUTHOR]

The subcellular localization and intracellular trafficking of Toll-like receptors (TLRs) critically regulate TLRs-mediated antimicrobial immunity and autoimmunity. Here, it is demonstrated that the E3 ubiquitin ligase RNF115 inhibits the post-endoplasmic reticulum (ER) trafficking of TLRs and TLRs-mediated immune responses by catalyzing ubiquitination of the small GTPases RAB1A and RAB13. It is shown that the 14-3-3 chaperones bind to AKT1-phosphorylated RNF115 and facilitate RNF115 localizing on the ER and the Golgi apparatus. RNF115 interacts with RAB1A and RAB13 and catalyzes K11-linked ubiquitination on the Lys49 and Lys61 residues of RAB1A and on the Lys46 and Lys58 residues of RAB13, respectively. Such a modification impairs the recruitment of guanosine diphosphate (GDP) dissociation inhibitor 1 (GDI1) to RAB1A and RAB13, a prerequisite for the reactivation of RAB proteins. Consistently, knockdown of RAB1A and RAB13 in Rnf115 +/+ and Rnf115 -/- cells markedly inhibits the post-ER and the post-Golgi trafficking of TLRs, respectively. In addition, reconstitution of RAB1A K49/61R or RAB13 K46/58R into Rnf115 +/+ cells but not Rnf115 -/- cells promotes the trafficking of TLRs from the ER to the Golgi apparatus and from the Golgi apparatus to the cell surface, respectively. These findings uncover a common and step-wise regulatory mechanism for the post-ER trafficking of TLRs., (© 2022 The Authors. Advanced Science published by Wiley-VCH GmbH.)

This paper is devoted to a nonautonomous SVIR epidemic model with relapse, that is, the recurrence rate is considered in the model. The permanent of the system is proved, and the result on the existence and uniqueness of globally attractive almost periodic solution of this system is obtained by constructing a suitable Lyapunov function. Some analysis for the necessity of considering the recurrence rate in the model is also presented. Moreover, some examples and numerical simulations are given to show the feasibility of our main results. Through numerical simulation, we have obtained the influence of vaccination rate and recurrence rate on the spread of the disease. The conclusion is that in order to control the epidemic of infectious diseases, we should increase the vaccination rate while reducing the recurrence rate of the disease.

Piper crocatum Ruiz & Pav. (P. crocatum), a traditional medicinal plant, has been shown to possess various pharmacological activities, including anticancer activity, antioxidant activity, antibacterial activity, anti-hyperglycemic activity, anti-allergic inflammatory activity and others. To identify the potential anti-allergic inflammatory effective constituents of P. crocatum, 13 single compounds were isolated from the methanol extract of P. crocatum leaves, and their structures were identified by contrasting their NMR spectroscopic data and previously published papers. First, the anti-allergic inflammatory activities of these single compounds were examined by accessing immune function related biomarkers such as nitric oxide (NO) and β-hexosaminidase. We found that the methanol extract and catechaldehyde (compound 1) potently suppressed NO production. Additionally, Western blot analysis showed that P. crocatum methanol extract and compound 1 suppressed the production of NO by reducing inducible nitric oxide synthase (iNOS) expression in lipopolysaccharide (LPS)-induced RAW264.7 macrophages. Consistent with these observations, P. crocatum methanol extract and compound 1 remarkably decreased β-hexosaminidase release from RBL-2H3 cells stimulated with 2,4-dinitrophenylated bovine serum albumin (DNP-BSA)-specific immunoglobulin E (IgE) antibodies. Furthermore, 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) assay indicated that P. crocatum methanol extract and compound 1 exhibited no cytotoxicity to RAW264.7 and RBL-2H3 cells. Based on these findings, compound 1 is suggested as an active anti-allergic inflammatory component of P. crocatum.

Different epidemic models with one or two characteristics of multi-group, age structure and spatial diffusion have been proposed, but few models take all three into consideration. In this paper, a novel multi-group SEIR epidemic model with both age structure and spatial diffusion is constructed for the first time ever to study the transmission dynamics of infectious diseases. We first analytically study the positivity, boundedness, existence and uniqueness of solution and the existence of compact global attractor of the associated solution semiflow. Based on some assumptions for parameters, we then show that the disease-free steady state is globally asymptotically stable by utilizing appropriate Lyapunov functionals and the LaSalle's invariance principle. By means of Perron-Frobenius theorem and graph-theoretical results, the existence and global stability of endemic steady state are ensured under appropriate conditions. Finally, feasibility of main theoretical results is showed with the aid of numerical examples for model with two groups which is important from the viewpoint of applications.

Dendropanax morbiferus H. Lév has been reported to have some pharmacologic activities and also interested in functional cosmetics. We found that the water extract of D. morbiferus leaves significantly inhibited tyrosinase activity and melanin formation in α-melanocyte stimulating hormone (MSH)-induced B16-F10 cells. D. morbiferus reduced melanogenesis-related protein levels, such as microphthalmia-associated transcription factor (MITF), TRP-1, and TRP-2, without any cytotoxicity. Two active ingredients of D. morbiferus, (10E)-9,16-dihydroxyoctadeca-10,17-dien-12,14-diynoate (DMW-1) and (10E)-(-)-10,17-octadecadiene-12,14-diyne-1,9,16-triol (DMW-2) were identified by testing the anti-melanogenic effects and then by liquid chromatography-tandem mass spectrometry (LC/MS/MS) analysis. DMW-1 and DMW-2 significantly inhibited melanogenesis by the suppression of protein kinase A (PKA)/cyclic AMP (cAMP)-responsive binding protein (CREB) and p38 MAPK phosphorylation. DMW-1 showed a better inhibitory effect than DMW-2 in α-MSH-induced B16-F10 cells. D. morbiferus and its active component DMW-1 inhibited melanogenesis through the downregulation of cAMP, p-PKA/CREB, p-p38, MITF, TRP-1, TRP-2, and tyrosinase. These results indicate that D. morbiferus and DMW-1 may be useful ingredients for cosmetics and therapeutic agents for skin hyperpigmentation disorders., (Copyright © 2020 Park, Yang, Guo, Li, Kim and Kim.)

A field experiment was carried out to study the effects of balanced fertilization on growth and development, yield, fruit quality and mineral content in 'Huang-guan' pear to provide a theoretical basis for the reasonable level of fertilization in pear orchards. Four treatments were arranged with 12-year old 'Huang-guan' pear trees from the same orchard: conventional fertilization (CK), low levels of N, P 2 O 5 and high level of S (T 1 ), medium levels of N, P 2 O 5 and S (T 2 ), high levels of N, P 2 O 5 and low level of S (T 3 ). The results showed that different treatments had little effect on the growth and development of current-year branch and leaves in the first year. However, in the se-cond year, T 1 treatment promoted the length and diameter of current-year branch by 16.2% and 11.4%, respectively. Continuous fertilization could increase the leaf mineral contents in different degrees. The contents of Cu, Fe, and Zn in leaves under T 1 treatment, Mg and B in leaves under T 2 treatment, and P and Mn in leaves under T 3 treatment were highest. Different fertilization levels had no significant effect on yield but on fruit quality. The contents of soluble sugars and vitamin C (Vc) were significantly increased by T 2 treatment, which was 4.2% and 7.1% higher than those in CK. However, T 1 significantly decreased contents of total soluble solid, soluble sugars and Vc, while highest organic acid content presented in T 3 . Fruit Fe content was positively correlated with soluble sugar content and fruit shape index, but was negatively correlated with single fruit mass, organic acids and Vc. Fruit P content was positively correlated with fruit shape index and firmness, but was negatively correlated with contents of soluble sugars, organic acids and Vc. Accordingly, T 2 could improve fruit quality and maintain the productivity, and thus should be the suitable fertilization strategy for the 'Huang-guan' pear management in desert area.

JM-101 is a developed functional food formula using water extract of Chaenomeles sinensis and Phyllostachys bambusoides for anti-obesity. Standardization and quality control of herb mixture is more difficult than those of single herb. Additionally, the estimation of mixing ratio is an essential requirement for standardization. This study aimed to develop an efficient analytical method for the standardization of JM-101 based on C. sinensis and P. bambusoides. Protocatechuic acid and p-coumaric acid were selected as marker compounds of JM-101. A mixture of the two medicinal materials (1:1 w/w) was extracted by water and then liquid-liquid extracted (LLE) by ethyl acetate. The supernatant was evaporated to dryness and dissolved in methanol for analysis. The extraction time, material-to-water ratio and ethyl acetate-to-water ratio were optimized by multi-response optimization based on response surface methodology (RSM). The established methods were validated in terms of linearity, precision, accuracy, repeatability, stability and recovery. The novel method based on LLE and RSM provides a sensitive, accurate analysis and excellent extraction efficiency of marker compounds in JM-101, without interruption of other compounds in JM-101. In conclusion, the developed simultaneous analytical method contributes to the standardization of two materials (C. sinensis and P. bambusoides) and JM-101.

The mechanism and electron transfer for pollutant dihydric phenol and biomolecule L-Cysteine (L-Cys) interaction in aqueous solution were studied by means of electrochemistry and UV-VIS spectrophotometry. Two forms of L-Cys, fixed on Au-electrode and free dissolved in the solution, were examined. The results showed that L-Cys of an ordered monolayer fixed on an Au electrode facilitated electron transfer and electrocatalytic redox of three isomers of dihydric phenol. However, free L-Cys does not show such facility. Furthermore, neither cleavage of the original chemical bond nor formation of a new chemical bond was observed in the molecules investigated, suggesting that L-Cys molecules may associate tightly with dihydric phenol molecules to form L-Cys . C(6)H(6)O(2)or (L-Cys) (2) . C(6)H(6)O(2) complex molecule via hydrogen-bonding. Different coordination numbers influence the electrochemical activity and behavior of associated complexes; thus, the function of biomolecules could be affected.