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The analysis of the cosmic microwave background data acquired by the Atacama Cosmology Telescope and the large-scale (⁠|$\ell \lesssim 1300$|⁠) Planck Telescope show a preference for the early dark energy (EDE) theory, which was set to alleviate the Hubble tension of the |$\Lambda$| cold dark matter (⁠|$\Lambda$| CDM) model by decreasing the sound horizon |$r_{s}$|⁠ , and gives |$H_{0} \approx 72$| km s |$^{-1}$| Mpc |$^{-1}$|⁠. However, the EDE model is commonly questioned for exacerbating the |$\sigma _8$| tension on top of the |$\Lambda$| CDM model, and its lack of preference from the late-time matter power spectrum observations, e.g. Baryon Oscillation Spectroscopic Survey. In light of the current obscurities, we inspect if the high redshift galaxy abundance, i.e. stellar mass function/density and luminosity function, can independently probe the EDE model. Our result shows that, compared to |$\Lambda$| CDM, the EDE model prediction at |$z\gt 10$| displays better consistency with the unexpectedly high results observed by the JWST. At lower redshift, the EDE model only fits the most luminous/massive end, with the majority of the data presenting better consistency with |$\Lambda$| CDM, implying that adding an extra luminosity/mass-sensitive suppression mechanism of the galaxy formation is required for EDE to explain all data around |$z\sim 7-10$|⁠. [ABSTRACT FROM AUTHOR]

Objective: The purpose of this study was to explore the clinical benefits of establishing an enteral nutrition (EN) pathway via percutaneous transhepatic cholangiography drainage (PTCD) catheterization in patients with late-stage malignant obstructive jaundice (MOJ).Methods: We selected 30 patients diagnosed as having late-stage MOJ with malnutrition. A dual-lumen biliary-enteral nutrition tube was placed via PTCD along with a biliary stent implantation. Postoperative EN was provided, and we observed the time taken for tube placement, its success rate, complications, and therapeutic efficacy.Results: Tube placement was successful in all 30 patients with an average procedural time of 5.7 ± 1.4 min with no tube placement complications. Compared to preoperative measures, there was a significant improvement in postoperative jaundice reduction and nutritional indicators one month after the procedure (p < 0.05). Post-placement complications included tube perileakage in 5 cases, entero-biliary reflux in 4 cases, tube blockage in 6 cases, tube displacement in 4 cases, accidental tube removal in 3 cases, and tube replacement due to degradation in 8 cases, with tube retention time ranging from 42 to 314 days, averaging 124.7 ± 37.5 days. All patients achieved the parameters for effective home-based enteral nutrition with a noticeable improvement in their quality of life.Conclusion: In this study, we found that the technique of establishing an EN pathway via PTCD catheterization was minimally invasive, safe, and effective; the tube was easy to maintain; and patient compliance was high. It is, thus, suitable for long-term tube retention in patients with late-stage MOJ. [ABSTRACT FROM AUTHOR]

China's governance of its aging society has been accompanied by rapid economic and social transformation, urbanization, population migration, and globalization. Although the results have been remarkable, there remain several major challenges faced by its aging society and faced by the country in building a holistic response system for aging issues. This article uses governance theories to analyze the role of the government and the corresponding governance mechanisms in China's aging society and further conducts an empirical analysis of its aging policies from 1982 to 2017. We found some progress in the policy area for addressing aging issues with an integrated governance system around the government evolving in China. This study sheds light on the favorable governance structure for addressing aging issues effectively, which involves the integration of social resources in governance. This governance structure can not only realize the effective allocation of social resources but also maximize the government's administrative resources. [ABSTRACT FROM AUTHOR]

Shaped ultrafast laser pulses were used to study and control the ionization dynamics of electronically excited pyrazine in a pump and probe experiment. For pump pulses created without feedback from the product signal, the ion growth curve (the parent ion signal as a function of pump/probe delay) was described quantitatively by the classical rate equations for internal conversion of the S2 and S1 states. Very different, non-classical behavior was observed when a genetic algorithm (GA) employing phase-only modulationwas used to minimize the ion signal at some pre-determined target time, T. Two qualitatively different control mechanisms were identified for early (T < 1.5 ps) and late (T > 1.5 ps) target times. In the former case, the ion signalwas largely suppressed for t < T,while for t » T, the ion signal produced by the GA-optimized pulse and a transform limited (TL) pulse coalesced. In contrast, for T > 1.5 ps, the ion growth curve followed the classical rate equations for t < T, while for t » T, the quantum yield for the GA-optimized pulse was much smaller than for a TL pulse. We interpret the first type of behavior as an indication that the wave packet produced by the pump laser is localized in a region of the S2 potential energy surface where the vertical ionization energy exceeds the probe photon energy, whereas the second type of behavior may be described by a reduced absorption cross section for S0 → S2 followed by incoherent decay of the excited molecules. Amplitude modulation observed in the spectrum of the shaped pulse may have contributed to the control mechanism, although this possibility is mitigated by the very small focal volume of the probe laser. [ABSTRACT FROM AUTHOR]

Coastal vegetation has been increasingly recognized as effective buffer against wind waves. Recent studies have advanced our understanding of wave dissipation process in vegetation (WDV). In intertidal environments, waves commonly propagate into vegetation fields with underlying tidal currents, which may alter WDV, but such influence is often overlooked. The key mechanism of WDV with co-existing currents are understudied, as previous studies have drawn contradictory conclusions on the effect of following currents on WDV. Subsequent laboratory experiments have partly explained the inconsistent conclusions, but relevant data are rarely available for theoretical or modelling development. Additionally, while the vegetation drag coefficient is a key factor influencing WDV, it is rarely reported for combined wave-current flows. This paper reports a unique dataset from two flume experiments, including 668 wave-only and wave with following/opposing current tests. A variety of data including wave height, drag coefficient, in-canopy velocity and acting force on mimic vegetation stem are recorded. This dataset is expected to assist future theoretical advancement on WDV, which may ultimately lead to more accurate prediction of wave dissipation capacity of real coastal wetlands. The dataset is available from figshare (https://doi.org/10.6084/m9.figshare.13026530.v2; Hu et al., 2020) with clear instructions for reuse. The current dataset will expand with additional WDV data from ongoing as well as planned future observation in real mangrove wetlands. [ABSTRACT FROM AUTHOR]

The electric field of a light wave accumulates a π phase shift as it passes through a focus. We show here how this effect, known as the Gouy phase, may be used to control the branching ratio of a unimolecular reaction when the products are formed with different numbers of photons. We demonstrate this control method for the ionization and dissociation of vinyl chloride, using absorption of 177 and 532 nm photons to induce a pair of interfering paths. Excellent agreement between the observed and calculated phase shift as a function of the axial coordinate of the laser focus indicates that fragmentation occurs via a ladder switching mechanism. The axial dependence of the modulation depth is evidence of loss of coherence at higher internal temperatures of the molecule. [ABSTRACT FROM AUTHOR]

Anion receptors based on an 8-thioureasubstituted quinoline withpentafluorinated (1a) or nonfluorinated (1b) biarylamide groups in the 2-position show similar binding of halideanions with somewhat higher association constants for the more acidicfluorinated derivative. Surprisingly, binding affinities for the halidesin the case of the nonfluorinated 1bare similar in nonpolarchloroform or polar DMSO as solvent. Thorough thermodynamic investigationsbased on NMR van’t Hoff analysis show that anion binding inchloroform is mainly enthalpically driven. In DMSO, entropy is thedriving force for the binding of the ions with replacement of attachedsolvent. [ABSTRACT FROM AUTHOR]

A novel quinoline-substituted crown ether has been synthesized as a receptor for ion pairs and its binding behavior was investigated in various solvents. The binding of ion pairs in [D6]DMSO and in mixed [D6]DMSO/CD3CN/CDCl3 solvents was studied and the results revealed positive cooperativity effects. As a novel solubilizing agent, the crown ether can extract halide salts into organic media, especially chloride salts. ESI MS provided evidence for the formation of salt-receptor complexes. A recycling experiment showed that the receptor can solubilize salts and can be recovered. This process can be performed as a cycle. This study validates the idea that a straightforward combination of a common anion receptor and a well-studied cation complexation moiety enables the formation of ion-pair receptors and solubilizers of salts in organic solvents. [ABSTRACT FROM AUTHOR]

Twelve new triazole derivatives of Phrymarolin were prepared from Phrymarolin I and the structures of all the derivatives were fully characterized by ¹H-NMR, 13C-NMR and MS spectral data analyses. Larvicidal activities against 4rd instar larvae of Culex pipiens pallens of these Phrymarolin analogues were assayed. Although the triazole derivatives of Phrymarolin showed certain larvicidal activity, they showed lower activity than Phrymarolin I. The typical non-natural groups triazole substituents reduced the larvicidal activity of Phrymarolin derivatives. [ABSTRACT FROM AUTHOR]

The binding behaviour of (thio)urea- and amide-functionalized quinoline-based anion receptors towards halide anions was investigated in detail in CDCl3 and [D6]DMSO solutions by using 1H and 19F NMR spectroscopic methods. The electronic, solvent, and fluoro-substitution effects were studied. The (thio)urea- and amide-functionalized quinoline-based anion receptors showed medium to strong anion affinity and good selectivity in solution. Single crystals of key compounds were obtained and studied by X-ray diffraction spectroscopy. [ABSTRACT FROM AUTHOR]

In order to develop new biorational pesticides, ten new 6-substituted ester derivatives of Celangulin-V were designed and synthesized. The structures of the new derivatives were confirmed by IR, ¹H-NMR, 13C-NMR and ESI-MS spectral analysis. Insecticidal activities of these compounds were tested against the third-instar larvae of Mythimna separata. Two derivatives (1.1, 1.2) showed higher insecticidal activities than Celangulin-V, with mortality of 75.0% and 83.3%, respectively. While four compounds (1.3, 1.4, 1.7, 1.8) denoted lower insecticidal activities, the others (1.5, 1.6, 1.9, 1.10) revealed no activities at a concentration of 10 mg.mL-1. The results suggest that C-6 substitutions of Celangulin-V are very important in determining the insecticidal activities of its ester-derivatives. That the acetyl (1.1) and propionyl (1.2) derivatives possessed much higher insecticidal activities than Celangulin-V itself supported the view that Celangulin-V has the potential to be a lead structure of semi-synthetic green insecticides. [ABSTRACT FROM AUTHOR]

In this study, we investigate the effects of high pressures (up to 600 MPa) applied at room temperature for 10 min on beef cooking loss and structure. The data on cooking loss, pH and protein solubility, as well as the electron microscopy, illustrate the changes in cooking loss and structure with high pressure processing (HPP). There is a significant reduction in cooking loss of beef with HPP. When the beef sample is imposed upon by 300 or 400 MPa, the cooking loss reduction is about 12%. Further, the pH of beef is dramatically increased as the pressure increases, and the pH increases by about 5% when imposed upon by 500 MPa. When a high pressure was applied at room temperature, the structure of the beef tissue apparently changed. Muscle fiber fragments gradually became slender and sarcomeres became lengthened. Our data indicated that high-pressure treatment on beef leads to stretching of the muscle fiber and an increase in the water-holding capacity. [ABSTRACT FROM AUTHOR]

We analyse the covariance of the one-dimensional mass power spectrum along lines of sight. The covariance reveals the correlation between different modes of fluctuations in the cosmic density field and gives the sample variance error for measurements of the mass power spectrum. For Gaussian random fields, the covariance matrix is diagonal. As expected, the variance of the measured one-dimensional mass power spectrum is inversely proportional to the number of lines of sight that are sampled from each random field. The correlation between lines of sight in a single field may alter the covariance. However, lines of sight that are sampled far apart are only weakly correlated, so that they can be treated as independent samples. UsingN-body simulations, we find that the covariance matrix of the one-dimensional mass power spectrum is not diagonal for the cosmic density field due to the non-Gaussianity and that the variance is much higher than that of Gaussian random fields. From the covariance, one will be able to determine the cosmic variance in the measured one-dimensional mass power spectrum as well as to estimate how many lines of sight are needed to achieve a target precision. [ABSTRACT FROM AUTHOR]

7-Pentafluorophenyl-1H-indole has the potential to be a key compound for the investigation of anion-π interactions in solution. Unfortunately, it was not possible to obtain it by aryl-aryl coupling reaction. Finally, it has been prepared by Bartoli indole synthesis. The key compound as well as analogues were submitted to preliminary studies of anion binding. Single crystals of two key receptors were obtained. [ABSTRACT FROM AUTHOR]

Objective: This study aimed to evaluate the efficacy of a double-lumen biliary-enteric tube (DBET) for enteral nutrition (EN) in individuals with malignant obstructive jaundice (MOJ). Methods: A retrospective cohort study was conducted using data from a prospectively maintained single-center database, including patients with MOJ. In the intervention group, DBET placement was performed concurrently with percutaneous transhepatic cholangiodrainage and biliary stenting, followed by postoperative EN (DBET-EN). In the control group, deep vein catheterization was undertaken after endoscopic biliary stenting, and parenteral nutrition (PN) was provided. A multivariable generalized linear model was used to assess the association between DBET-EN and 6-month mortality. Results: A total of 74 patients were included in this study, comprising 28 patients in the intervention group (DBET-EN group) and 46 patients in the control group (PN group). Within the 6-month follow-up, 5 patients (17.9%) in the DBET-EN group and 20 (43.5%) in the PN group died. The multivariable generalized linear model demonstrated a significantly reduced 6-month mortality in the DBET-EN group compared to the PN group (adjusted odds ratio [OR]: 0.25, 95% CI: 0.08–0.81, P = 0.020). Secondary outcomes indicated that patients in the DBET-EN group had lower 9-month mortality rates and longer tube retention durations compared to the PN group (all adjusted P < 0.05). Postoperative liver function improved similarly in both groups. At 3, 6, and 9 months postoperatively, patient-generated subjective global assessment (PG-SGA) scores and the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-C30 (EORTC QLQ-C30) scores were significantly higher in the DBET-EN group than in the PN group (P < 0.05). Conclusion: The implementation of DBET for EN in patients in the advanced stage of MOJ proved to be a minimally invasive and safe intervention. It significantly improved patients' nutritional status and quality of life while reducing mortality. [ABSTRACT FROM AUTHOR]

Galaxy–galaxy strong gravitational lensing (GGSL) is a powerful probe for the formation and evolution of galaxies and cosmology, while the sample size of GGSLs leads to considerable uncertainties and potential bias. The China Space Station Telescope (CSST, to be launched in late 2026) will conduct observations across 17 500 square degrees of the sky, capturing images in the |$ugriz$| bands with a spatial resolution comparable to that of the Hubble Space Telescope. We ran a set of Monte Carlo simulations to predict that the CSST's wide-field survey will observe |$\sim$| 160 000 galaxy–galaxy strong lenses over its lifespan, increasing the number of existing galaxy–galaxy strong lens samples by three orders of magnitude. This is comparable to the capabilities of the |$\it Euclid$| telescope but with the added benefit of additional colour information. Specifically, the CSST can detect strong lenses with Einstein radii about |$0.64\pm 0.42 ^{\prime \prime }$|⁠ , corresponding to the velocity dispersions of |$217.19 \pm 50.55 \, \text{km/s}$|⁠. These lenses exhibit a median magnification of |$\sim$| 5. The apparent magnitude of the unlensed sources in the g band is |$25.87 \pm 1.19$|⁠. The signal-to-noise ratio of the lensed images covers a range of |${\sim} 20$| to |${\sim} 1000$|⁠ , allowing us to determine the Einstein radius with an accuracy ranging from |${\sim} 1~{{\ \rm per\ cent}}$| to |${\sim} 0.1~{{\ \rm per\ cent}}$|⁠ , ignoring various modelling systematics. Our estimates indicate that CSST can observe rare systems like double source-plane and spiral galaxy lenses. The above selection functions of the CSST strong lensing observation help optimize the strategy of finding and modelling GGSLs. [ABSTRACT FROM AUTHOR]

The spectroscopic survey of the China's Space Survey Telescope (CSST) is expected to obtain a huge number of slitless spectra, including more than one hundred million galaxy spectra and millions of active galactic nuclei (AGNs) spectra. By making use of these spectra, we can measure the Baryon Acoustic Oscillation (BAO) signals over large redshift ranges with excellent precisions. In this work, we predict the CSST measurements of the post-reconstruction galaxy power spectra at |$0\lt z\lt 1.2$| and pre-reconstruction AGN power spectra at |$0\lt z\lt 4$|⁠ , and derive the BAO signals at different redshift bins by constraining the BAO scaling parameters using the Markov Chain Monte Carlo method. Our result shows that the CSST spectroscopic survey can provide accurate BAO measurements with precisions higher than 1 and 3 per cent for the galaxy and AGN surveys, respectively. By comparing with current measurements in the same range at low redshifts, this can improve the precisions by a factor of |$2\sim 3$|⁠ , and similar precisions can be obtained in the pessimistic case. We also investigate the constraints on the cosmological parameters using the measured BAO data by the CSST , and obtain stringent constraint results for the energy density of dark matter, Hubble constant, and equation of state of dark energy. [ABSTRACT FROM AUTHOR]

Type Ia supernova (SN Ia) as a standard candle is an ideal tool to measure cosmic distance and expansion history of the Universe. Here, we investigate the SN Ia photometric measurement in the China Space Station Telescope Ultra Deep Field (CSST-UDF) survey, and study the constraint power on the cosmological parameters, such as the equation of state of dark energy. The CSST-UDF survey is expected to cover a 9 deg2 sky area in 2 yr with 250 s × 60 exposures for each band. The magnitude limit can reach i ≃ 26 AB mag for 5σ point source detection with a single exposure. We generate light-curve mock data for SNe Ia and different types of core-collapse SNe (CCSNe). sncosmo is chosen as the framework by utilizing the salt3 model to simulate SN Ia data. After selecting high-quality data and fitting the light curves, we derive the light-curve parameters and identify CCSNe as contamination, resulting in ∼2200 SNe with an |$\sim\!\! 7{{\ \rm per\, cent}}$| CCSN contamination rate. We adopt a calibration method similar to Chauvenet's criterion, and apply it to the distance modulus data to further reduce the contamination. We find that this method is effective and can suppress the contamination fraction to |$\sim\!\! 3.5{{\ \rm per\, cent}}$| with 2012 SNe Ia and 73 CCSNe. In the cosmological fitting stage, we did not distinguish between SNe Ia and CCSNe. We find that the constraint accuracies on ΩM, ΩΛ, and w are about two times better than the current SN surveys, and they could be further improved by a factor of ∼1.4 if including the baryon acoustic oscillation data from the CSST spectroscopic wide-field galaxy survey. [ABSTRACT FROM AUTHOR]

As a Stage IV space-based telescope, the China Space Station Telescope (CSST) can perform photometric and spectroscopic surveys simultaneously to explore the Universe efficiently in extreme precision. In this work, we investigate several powerful CSST cosmological probes, including cosmic shear, galaxy–galaxy lensing, photometric and spectroscopic galaxy clustering, and number counts of galaxy clusters, and study the capability of these probes by forecasting the results of joint constraints on the cosmological parameters. By referring to real observational results, we generate mock data and estimate the measured errors based on CSST observational and instrumental designs. To study systematic effects on the results, we also consider a number of systematics in CSST photometric and spectroscopic surveys, such as the intrinsic alignment, shear calibration uncertainties, photometric redshift uncertainties, galaxy bias, non-linear effects, instrumental effects, etc. The Fisher matrix method is used to derive the constraint results on the cosmological and systematic parameters from individual or joint surveys. We find that the joint constraints achieved by including all these CSST cosmological probes can significantly improve the results from current observations by one order of magnitude at least, which gives Ωm and σ 8 <1 per cent accuracy and w 0 and wa <5 and 20 per cent accuracy, respectively. This indicates that CSST photometric and spectroscopic multi-probe surveys could provide powerful tools with which to explore the Universe and greatly improve the studies of relevant cosmological problems. [ABSTRACT FROM AUTHOR]

China Space Station Telescope (CSST) is a forthcoming powerful Stage IV space-based optical survey equipment. It is expected to explore a number of important cosmological problems in extremely high precision. In this work, we focus on investigating the constraints on neutrino mass and other cosmological parameters under the model of cold dark matter with a constant equation of state of dark energy (w CDM), using the mock data from the CSST photometric galaxy clustering and cosmic shear surveys (i.e. 3 × 2 pt). The systematics from galaxy bias, photometric redshift uncertainties, intrinsic alignment, shear calibration, baryonic feedback, non-linear, and instrumental effects are also included in the analysis. We generate the mock data based on the COSMOS catalogue considering the instrumental and observational effects of the CSST , and make use of the Markov chain Monte Carlo method to perform the constraints. Comparing to the results from current similar measurements, we find that CSST 3 × 2 pt surveys can improve the constraints on the cosmological parameters by one order of magnitude at least. We can obtain an upper limit for the sum of neutrino mass Σ m ν ≲ 0.36 (0.56) eV at 68 per cent (95 per cent) confidence level (CL), and Σ m ν ≲ 0.23 (0.29) eV at 68 per cent (95 per cent) CL if we ignore the baryonic effect, which is comparable to the Planck results and much better than the current photometric surveys. This indicates that the CSST photometric surveys can provide stringent constraints on the neutrino mass and other cosmological parameters, and the results also can be further improved by including data from other kinds of CSST cosmological surveys. [ABSTRACT FROM AUTHOR]

The likelihood function is a crucial element of parameter estimation. In analyses of galaxy overdensities and weak lensing shear, one often approximates the likelihood of the power spectrum with a Gaussian distribution. The posterior probability derived from such a likelihood deviates considerably from the exact posterior on the largest scales probed by any survey, where the central limit theorem does not apply. We show that various forms of Gaussian likelihoods can have a significant impact on the estimation of the primordial non-Gaussianity parameter fNL from the galaxy angular power spectrum. The Gaussian plus log-normal likelihood, which has been applied successfully in analyses of the cosmic microwave background, outperforms the Gaussian likelihoods. Nevertheless, even if the exact likelihood of the power spectrum is used, the estimated parameters may be still biased. As such, the likelihoods and estimators need to be thoroughly examined for potential systematic errors. [ABSTRACT FROM AUTHOR]

The ionization/dissociation mechanism of cyclopentanone has been experimentally investigated in molecular beam by irradiating with intense 394 and 788 nm laser fields with pulse duration of 90 fs. The range of laser intensities varied from 3×1013 to 4×1014 W/cm2. For both wavelengths, the singly charged parent ion is observable while the doubly charged one cannot be found easily, although the fragmentation pattern supports its presence. Meanwhile, the extent of fragmentation at 788 nm is less than that in the 394 nm case. We quantitatively analyze the ionization processes of cyclopentanone in intense femtosecond laser by comparing the calculation results of ionization rate constants obtained from Ammosov-Delone-Krainov, Keldysh, and Keldysh-Faisal-Reiss (KFR) theories based on hydrogenlike atom model. We also compare the experimental and theoretical results; the generalized KFR theory is found to be useful in predicting the ionization yields of singly and doubly charged cyclopentanone ion. To interpret the dissociation patterns of the cyclopentanone ions, we have used the Rice-Ramsperger-Kassel-Marcus theory with the potential surfaces obtained from the ab initio quantum chemical calculations. [ABSTRACT FROM AUTHOR]

Herein, a novel nanocomposite organic solvent nanofiltration (OSN) membrane has been facilely fabricated by a highly-efficient one-step co-deposition of mussel-inspired catechol and octaammonium polyhedral oligomeric silsesquioxane (POSS-NH 3 + Cl - ) onto supports. The basic properties and morphologies of the co-deposited nanocomposite membranes were investigated with various physicochemical characterizations in detail. Attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectra proved the present of POSS nanoparticles on membrane surface. X-ray photoelectron (XPS) results suggested the optimal ratio of POSS-NH 3 + Cl - and catechol for co-deposition. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) images demonstrated the formation of a layer on support surface. The optimized nanocomposite membrane exhibited an ethanol (EtOH) permeance of 1.26 L m −2 h −1 bar −1 with a rejection of 99% to Rose Bengal (RB). The novel membrane also exhibited remarkable separation performance for dyes removal from a wide range of solvents including challenging polar aprotic and strongly swelling solvents. Particularly, the nanocomposite membrane demonstrated stable performances during a two-day long term test in DMF for RB concentration. In addition to providing a highly-efficient way to high-performance OSN membrane, this work may stimulate the bio-inspired design of advanced nanocomposite membranes for environmental applications. [ABSTRACT FROM AUTHOR]

Antelope horn is a valuable Chinese traditional medicine and widely used in clinic. However, with the deterioration of antelope’s living environment and a lot of killing, the saiga population begins falling and in some places plummet. Since the increasing demand of this expensive and good bioactive medicine, the horn of artiodactyla animals is often used as the antelope horn. The adulterated or impostor not only cause damage to clinical medicine but also affect the antelope resources protection and sustainable development. Here, in order to establish a melting curve analysis (MCA) method to distinguish the antelope horn from other animal horns and identify the decoction pieces and Chinese patent medicine in a fast and easy way, animal horns and its decoction pieces, Chinese patent medicines were collected from the market and the DNA of all the collected samples were extracted. The melting curve of two universal fragments (COI andCytb) was scanned andCytb was selected as feasibility fragment for identifying authentic antelope horn from eight adulterant animal horns. After optimizing the condition for MCA, inspecting the precision and the replication of the method, a reference melting curve modern was established and we performed MCA on the antelope horns, fakes, and adulterants on a 1:1 mix, decoction pieces, and Chinese patent medicine. Thus, this study provides fast and easy methods so that MCA can detect the truth, fakes, and adulterations of antelope horns. [ABSTRACT FROM AUTHOR]

When considering energy consumption and environmental issues, solvent-resistant nanofiltration (SRNF) based on polymeric materials emerges as a process for substituting conventional separation processes of organic solutions, such as distillation, which consume high amounts of energy. Because SRNF does not involve phase transition, this process can potentially decrease the energy consumption and solvent waste and increase the yield of active components. Such improvements could significantly benefit a number of fields, such as pharmaceutical manufacturing and catalysis recovery, among others. Therefore, SRNF has gained a lot of attention since the recent introduction of solvent-stable polymeric materials in the manufacture of nanofiltration membranes. The membrane materials and the membrane structures depending on the fabrication methods determine the separation performance of polymeric SRNF membranes. Therefore, this article gives a comprehensive overview of the current state-of-art technologies of generating membrane materials and corresponding fabrication methods for SRNF membranes made from polymeric materials expected to provide the most benefit. The transport mechanisms and the corresponding models of SRNF membranes in organic media are also reviewed to better understand the mass transfer process. Various SRNF applications, such as in pharmaceutical and catalyst, among others, are also discussed. Finally, the difficulties and future research directions to overcome the challenges faced by SRNF processes are proposed. [ABSTRACT FROM AUTHOR]

Phytochemical study of Cymbaria dahurica L. afforded 16 compounds, including 12 flavonoids ( 1 – 12 ) and 4 iridoids ( 13 – 16 ). Structure elucidation of these compounds was generated by a combination of spectroscopic means (ESI-MS, 1 H and 13 C NMR) and comparisons with the published data. This is the first report of isolation of compounds ( 1 – 6 , 10 – 16 ) from C. dahurica and compounds ( 5 , 10 , 12 ) from the family Scrophulariaceae, respectively. The chemotaxonomic data can support the genus Cymbaria being accepted as a member of transitional taxa between the family Scrophulariaceae and Orobanchaceae. [ABSTRACT FROM AUTHOR]

A femtosecond double-pulse laser was used to induce the plasma of silicon in air. The laser wavelength was 800 nm. The interpulse delay of the femtosecond double-pulse was from -20 ps to 100 ps. During the experiment, the spectral line was fixed at the wavelength of 288.157 nm. The emission intensity was observed to lead to a significant increase by choosing the proper sample position. The range of the sample position is from 5.17 mm to 5.27 mm. And, the best sample position for the higher laser fluence was different from the position for the lower laser fluence. At the higher laser fluence, the optimized emission intensity can be obtained at either side of the best focal position for all interpulse delays of the double-pulse. The phenomena can be explained by the nonlinear propagation of the femtosecond laser pulse in air. At the lower laser fluence, the best sample position will change from one side to both sides with the increase of the interpulse delay of the double-pulse. The results showed that the effect of the sample position can be especially advantageous in the context of femtosecond double-pulse laser-induced breakdown spectroscopy. The study will lead a further improvement in the applications of the femtosecond double-pulse laser. [ABSTRACT FROM AUTHOR]

A train of three equally spaced femtosecond laser pulses is employed to control the photoionization/photodissociation processes of cyclopentanone. With the increase of pulse separation, a strong modulation of product ion yield is observed. More than ten-fold changes of ion yield ratio between different products can be realized. The experimental observations further explain the compositions and formation pathways of peaks in the mass spectra. The controlling mechanisms are also discussed. [ABSTRACT FROM AUTHOR]

Calculations on the dynamics of the reaction O(1D) + HBr → OH + Br are performed on the ab initio potential energy surfaces (PESs) of the ground state given by Peterson [Peterson K A J. Chem. Phys.113 4598 (2000)] using the quasi-classical trajectory (QCT) method. The product distribution of the dihedral angle, P(φr), and that of the angle between k and j′, P (θr), are presented in three dimensions. Moreover, we also investigate the reagent vibrational excitation effects on the two polarization-dependent generalized differential cross sections (PDDCS), PDDCS00 and PDDCS20, in the center-of-mass frame. The results indicate that the vector properties are sensitive to the reagent vibrational quantum number. [ABSTRACT FROM AUTHOR]

Abstract: The interaction between hydrogen sulfite (H2S) and graphene was investigated by density functional theory calculations and nonequilibrium Green’s function formalism. The structural and electronic properties of H2S–graphene systems were studied by tuning the geometries of H2S molecule toward 2D nanosheets of pristine, defective and doped graphene. It was found that Ca, Co and Fe doped and defective graphene nanosheets show much higher affinities to H2S molecule in comparison to pristine graphene. The strong interactions between H2S and graphene nanosheets modified with transition metals can lead to dramatic changes to the electronic and magnetic properties of graphene. The electronic transport behaviors of Fe-doped graphene nanosheets indicate that the chemical sensors constructed with the materials could exhibit much higher sensitivity for detecting H2S gas, in comparison with that of devices made with pristine graphene. It is possible to design H2S chemical sensors with highly improved performances, using graphene nanosheets as sensing materials with appropriate metal dopants or defects. In addition, the graphene doped with Si absorbs H2S molecule through forming Si–S bond, compared to the weak physisorption of H2S molecule onto pristine and the B, N doped graphene. [Copyright &y& Elsevier]

With 84 native species, China is a center of distribution of the genus Salvia (Lamiaceae). These species are mainly distributed in Yunnan and Sichuan provinces (southwestern China), notably the Hengduan Mountain region. Traditionally, the Chinese Salvia has been classified into four subgenera, Salvia, Sclarea, Jungia, and Allagospadonopsis. We tested this classification using molecular phylogenetic analysis of 43 species of Salvia from China, six from Japan, and four introduced species. The nuclear ribosomal internal transcribed spacer region and three chloroplast regions ( rbcL, matK, and trnH-psbA) were analyzed by maximum parsimony, maximum likelihood, and Bayesian methods. Our results showed that the Chinese (except Salvia deserta) and Japanese Salvia species formed a well-supported clade; S. deserta from Xinjiang grouped with Salvia officinalis of Europe. In addition, all introduced Salvia species in China were relatively distantly related to the native Chinese Salvia. Our results differed from the subgeneric and section classifications in Flora Reipublicae Popularis Sinicae. We suggested that sections Eusphace and Pleiphace should be united in a new subgenus and that sect. Notiosphace should be removed from subg. Sclarea and form a new subgenus. Our data could not distinguish a boundary between subg. Allagospadonopsis and sect. Drymosphace (subg. Sclarea); the latter should be reduced into the former. Further clarification of the phylogenetic relationships within Salvia and between Salvia and related genera will require broader taxonomic sampling and more molecular markers. [ABSTRACT FROM AUTHOR]

The mass spectra of a series of cycloketone molecules, cyclopentanone (CPO), cyclohexanone (CHO), cycloheptanone (CHPO), and cyclooctanone (COO) are measured in a 788 or 394 nm laser field with 90 fs pulse duration and the intensity ranging from 5 × 1013W/cm2to 2 × 1014W/cm2. At 788 nm, a dominated parent ion peak and some weak peaks from the fragment ions CnHmare observed for CPO and CHO (a ratio P/T, the parent ion yield to the total ion yield, is 81.6% and 52.6%, respectively). But the extensive fragment ion peaks are observed with the greatly reduced parent ion peak for CHPO (P/T5.5%) and that are even hard to be identified for COO. These observations are interpreted explicitly in the frame of the significant resonant effect of their cation photoabsorption on ionization and dissociation of these molecules. The present work also suggests that a nonadiabatic ionization occurs with a nuclear rearrangement due to the H movement in these molecules during the ionization in an intense femtosecond laser field. [ABSTRACT FROM AUTHOR]

Highlights: [•] Eight compounds were isolated from the roots of Vitis heyneana Roem. &Schult. [•] It is the first report of six compounds from Vitis heyneana. [•] Two compounds were reported from Vitaceae for the first time. [•] The analysis data suggested that V. heyneana is closely related to Vitis thunbergii. [Copyright &y& Elsevier]

Coherent control of fragmentation of CH3I using shaped femtosecond pulse train is investigated. The dissociation processes can be modulated by changing the separation of the shaped pulse train, and the yield of I+ under the irradiation of the optimal pulse is significantly increased compared with that using the transform-limited pulse. We discuss the control mechanism of dissociation processes with coherent interference in time domain. A three-pulse control model is proposed to explain the counterintuitive experimental results. [ABSTRACT FROM AUTHOR]

The strong-field coherent control of the nonresonant ionization of nitrous oxide using shaped pulses is investigated. We study the dependence of periodic coherent oscillation of the total ionization yield on the variation of laser phase parameters. The physical mechanism of the strong-field coherent control is investigated experimentally and theoretically by the nonresonant spectral phase interferences in the frequency domain. We show that the intense shaped pulses with broadband and off-resonance can be used as a robust strong-field coherent control method. [ABSTRACT FROM AUTHOR]