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Background and objectiveRopivacaine hydrochloride is a commonly used local anesthetic in clinics. However, local injection or continuous infusion of ropivacaine has been associated with several disadvantages. Accordingly, it is important to develop a new controlled release system for local administration of ropivacaine to achieve a prolong anesthetic effect, improve efficacy, and minimize the side effects.MethodsWe developed injectable hydroxypropyl chitin thermo-sensitive hydrogel (HPCH) combined with hyaluronan (HA), which was used to synthesize a ropivacaine (R)-loaded controlled release system. We then conducted drug release test and cytotoxicity assay in vitro. Importantly, we examined the analgesic effects and biocompatibility of this system in vivo by injecting different concentrations of R-HPCH-HA (7.5, 15, 22.5 mg/mL), ropivacaine hydrochloride (RHCL, 7.5 mg/mL), or saline (all in 0.5 mL) near the sciatic nerve in rats.ResultsR-HPCH-HA induced concentration-dependent thermal-sensory blockade and motor blockade in vivo. In hot plate test, R-HPCH-HA (22.5 mg/mL) induced a significant longer thermal-sensory blockade (17.7±0.7 hours), as compared with RHCL(7.5 mg/mL, 5.7±0.8 hours, n=6/group, pHCL(3.5±0.8 hours, pHCL, as indicated by the higher cell viability in vitro (n=8/group).ConclusionOur findings in a sciatic nerve block model demonstrated that the injectable, ropivacaine-loaded controlled release system effectively prolonged the local analgesic effect in rats without notable side effects.

We consider the geometric phase induced by the two-level atom with inertial and uniformly accelerated motion, which is coupled to massless scalar field in cosmic string spacetime. Our result shows that when the atom is very close to the string, the geometric phase of cosmic string spacetime is ν times that of Minkowski spacetime. By comparing phase difference induced by the inertial and accelerated motion, we find the sensitive dependence of the phase difference on deficit angle parameter, transition frequencies of the atom, atomic acceleration and the initial state parameter. We also obtain phase difference increases with deficit angle parameter and the atomic acceleration. Although reaching the measurable magnitude of geometric phase requires extremely high acceleration, the detection experiment may be implemented in the future. Our work may suggest a possible way to detect cosmic string scalar field by using geometric phase.

In this work, using the Gaussian process, we explore the potentiality of future gravitational wave (GW) measurements to probe cosmic opacity at high redshifts through comparing its opacity-free luminosity distance (LD) with the opacity-dependent one from the combination of Type Ia supernovae (SNIa) and gamma-ray bursts (GRBs). The GW data, SNIa and GRB data are simulated from the measurements of the future Einstein Telescope, the actual Pantheon compilation and the latest observation of GRBs compiled by L. Amati {\it et al}, respectively. A nonparametric method is proposed to probe the spatial homogeneity of cosmic transparency at high redshift by comparing the LD reconstructed from the GW data with that reconstructed from the Pantheon and GRB data. In addition, the cosmic opacity is tested by using the parametrization for the optical depth, and the results show that the constraints on cosmic opacity are more stringent than the previous ones. It shows that the future GW measurements may be used as an important tool to probe the cosmic opacity in the high redshift region., 21pages, 3 figures accepted by EPJC. arXiv admin note: text overlap with arXiv:1912.02327

Anaerobic ammonium oxidation (anammox) is a cost-effective nitrogen removal pathway but instinctively generated nitrate limits its application. A novel anammox aggregate reduced the production of nitrate significantly with efficient removal of ammonia and nitrite in this work. The results demonstrated that the internal heterotrophic nitrate removal (IHNAR) pathway exists stably at inner of anammox aggregates, which eliminated 42.31 ± 3.85 % nitrate generated in anammox at without consuming external carbon source. The observed volatile fatty acids (VFAs) and adequate protein, polysaccharide and humic acids in the aggregates verified that the in-situ fermentation supplied sustainably endogenous carbon sources for the IHNAR. The efficient interspecies cooperation between anammox bacteria, heterotrophic denitrifiers and fermentative bacteria was identified, as the intrinsic justification for the obtained sustainability of IHNAR pathway. The findings were expected to provide theoretical guidance for promotions and applications of the anammox process with high-efficiency total nitrogen removal capabilities.

Direct-drive wave energy converter (DD-WEC) is limited by low power density caused by low direct-drive speed. A tubular hybrid field-modulated linear generator is proposed to improve the performance of DD-WEC. The generator adopted a field-modulated design to increase the output voltage of the linear generator. A hybrid excited field coil can be used to adapt to different wave situations and effectively improve the output performance of this kind of generator. The operation of the proposed generator is analyzed, and the generator performance is evaluated through finite element method and compared with those of three other generators, namely, a field modulated linear generator with parallel magnetic-circuit, a secondary surface PM field modulated linear generator, and a secondary surface PM fractional-slot linear generator. Results show that the proposed generator exhibits high power density and low cogging force. The steady output power and output voltage of are marginally higher in the proposed generator than in the conventional generators.

In this work, we explore the potentiality of future gravitational wave (GW) and Type Ia supernovae (SNe Ia) measurements to detect cosmic opacity by comparing the opacity-free luminosity distance (LD) of GW events with the opacity-dependent LD of SNe Ia observations. The GW data are simulated from the future measurements of the ground-based Einstein Telescope (ET) and the space-borne Deci-Herz Interferometer Gravitational wave Observatory (DECIGO). The SNe Ia data are simulated from the observations of the Wide Field Infrared Survey Telescope (WFIRST) that will be collected over the next few decades. A binning method is adopted to match the GW data with the SNe Ia data at the same redshift z with a selection criterion , and most of the available data from the GW measurements is employed to detect cosmic opacity due to improvements in the distribution of the future SNe Ia observations. Results show that the uncertainties of the constraints on cosmic opacity can be reduced to and 0.0014 at the confidence level (CL) for 1000 data points from the ET and DECIGO measurements, respectively. Compared with the allowable limits of intergalactic opacity obtained from quasar continuum observations, these future astronomical observations can be used to verify the cosmic opacity. In this way, GW and SNe Ia measurements can be used as important and effective tools to detect cosmic opacity in the future.

Epoxyeicosatrienoic acid (EET) has wide applications due to the unique biological effects of anti‑hyperlipidemia, inhibition of platelet aggregation, anti‑inflammation, anti‑cancer, anti‑lipid oxidation and the promotion of brain tissue development. The present study investigated whether EET ameliorates cerebral ischemia‑reperfusion injury (CIRI) by inhibiting inflammatory factors and pannexin. Specific pathogen‑free 7‑week‑old male Sprague‑Dawley rats were randomly divided into three groups: Sham, CIRI and EET. Neurological deficit scores, cerebral infarct volume and cerebral edema were assessed in CIRI rats. Enzyme‑linked immunosorbent assays were performed to detect tumor necrosis factor‑α, interleukin‑6, nuclear factor‑κB and inducible nitric oxide synthase (iNOS) levels, and western blot analysis was performed also used to assess cleaved caspase‑3, phospholipase A2 (PLA2), cyclooxygenase‑2 and prostaglandin E2 (PGE2) protein expression levels. EET ameliorated cerebral injury and CIRI‑induced cleaved caspase‑3 protein expression levels in rats. EET additionally suppressed CIRI‑induced inflammation reactions and iNOS protein expression in rats. Furthermore, the protein expression levels of PLA2, PGE2 and pannexin‑1 in CIRI rats were inhibited by treatment with EET. These results indicated that EET reduces CIRI by inhibiting inflammation and levels of cleaved caspase‑3, PLA2, PGE2 and pannexin-1.

A validation of the cosmic distance-duality relation (CDDR) is crucial because any observational departure from it could be a signal of new physics. In this work, we explore the potentialities of luminosity distance data from the gravitational wave (GW) standard sirens of future Einstein Telescope (ET) to test the CDDR. The angular diameter distance data are used from the galaxy clusters samples and the baryon acoustic oscillation (BAO) measurements. The basic advantage of GW measurements substituting for the observations from the type Ia supernovae (SNIa) is that the luminosity distance from it is insensitive to the non-conservation of the number of photons. By simulating 550 and 1000 data points of future GW measurements in the low redshift range $0, Comment: Submitted to PRD 17pages,3figs

In this work, using the Gaussian Process, we explore the potentiality of future gravitational wave (GW) measurement to probe cosmic opacity through comparing its opacity-free luminosity distance (LD) with the opacity-dependent one from type Ia supernovae (SNIa). GW data points are simulated from the third generation Einstein Telescope, and SNIa data are taken from the Joint Light Analysis (JLA) or Pantheon compilation. The advantages of using Gaussian Process are that one may match SNIa data with GW data at the same redshift and use all available data to probe cosmic opacity. We obtain that the error bar of the constraint on cosmic opacity can be reduced to $\sigma_{\epsilon}\sim 0.011$ and $0.006$ at $1\sigma$ confidence level (CL) for JLA and Pantheon respectively in a cosmological-independent way. Thus, the future GW measurements can give competitive results on the cosmic opacity test. Furthermore, we propose a method to probe the spatial homogeneity of the cosmic transparency through comparing the reconstructed LD from the mock GW with the reconstructed one from SNIa data in a flat $\Lambda$CDM with the Gaussian Process. The result shows that a transparent universe is favored at $1\sigma$ CL, although the best-fit value of cosmic opacity is redshift-dependent., Comment: 19pages, 3figures, accepted by PRD

In this study, notable peroxymonosulfate (PMS) activation enhancement accomplished by coupling zeolite-supported nano-zero-valent Iron (z-nZVI) with weak magnetic field (WMF) was reported. The z-nZVI/PMS/WMF possessed 25% enhancement (when pH = 3) in acid orange 7 (AO7) removal efficiency and 2–3 folds enhancement in degradation rate and could extend pH range when compared with z-nZVI/PMS process. SEM-mapping and XRD analysis revealed that WMF accelerated the dissolution of z-nZVI to promote the formation of free radicals. Electron paramagnetic resonance (EPR) spectroscopy and radical scavenger studies verified the formation of SO4 −, OH and O2 −. It was demonstrated that the generation of O2 − was due to the reaction of Fe0 with PMS rather than the diffusion of O2. The role of WMF was explained by the magnetoconvection theory and a possible reaction mechanism was derived. The significant improvement was also observed on the degradation of other contaminants including tetracycline and norfloxacin (50% enhancement). Moreover, regenerating z-nZVI by recycled zeolites makes water treatment much easier, more feasible and more economical.

In this paper, we perform cosmological-model-independent tests for the distance-duality (DD) relation η(z)=D L(1+z)−2/D A by combining the angular diameter distance D A(or comoving distances D c ) with the luminosity distance D L. The D A are provided by two galaxy clusters samples compiled by De Filippis et al. (the elliptical β model), Bonamente et al. (the spherical β model), the D c are obtained from Hubble parameter data and D L are given from the Union2.1 supernovae (SNe) Ia compilation. We employ two methods, i.e., method A: binning the SNe Ia data within the range Δz=|z−z SNe

In this paper, we perform a cosmological model-independent test of the cosmic distance-duality relation (CDDR) in terms of the ratio of angular diameter distance (ADD) $D=D_{\rm A}^{\rm sl}/D_{\rm A}^{\,\rm s}$ from strong gravitational lensing (SGL) and the ratio of luminosity distance (LD) $D^\ast=D_{\rm L}^{\,\rm l}/D_{\rm L}^{\,\rm s}$ obtained from the joint of type Ia supernovae (SNIa) Union2.1 compilation and the latest Gamma-Ray Bursts (GRBs) data, where the superscripts s and l correspond to the redshifts $z_{\,\rm s}$ and $z_{\,\rm l}$ at the source and lens from SGL samples. The purpose of combining GRB data with SNIa compilation is to test CDDR in a wider redshift range. The LD associated with the redshits of the observed ADD, is obtained through two cosmological model-independent methods, namely, method A: binning the SNIa+GRBs data, and method B: reconstructing the function of DL by combining the Crossing Statistic with the smoothing method. We find that CDDR is compatible with the observations at $1\sigma$ confidence level for the power law model which is assumed to describe the mass distribution of lensing systems with method B in a wider redshift range., Comment: 18pages and 5figures

With the deployment of sensor and communication network, the conventional power system is transformed into a multi-dimensional heterogeneous complex system, which is known as Cyber-Physical Power System (CPPS). On the one hand, CPPS has developed new abilities of real-time sensing, dynamic control and information services; on the other hand, massive information interaction in CPPS has posed more potential threats of cyber-attacks. Recently, the severe blackouts caused by cyber-attacks have set the alarm for cyber security in power system worldwide. However, research on CPPS attacks is deficient nationwide, and there is a lack of comprehensive understanding in concepts, manners and scenarios of CPPS attacks. The purpose of the paper is to give an overall view of cyber-attacks in CPPS from the perspectives of definition, classifications, typical scenarios, and prospects, and provides some new thoughts for researchers in related fields.

We test the distance-duality (DD) relation by combining the angular diameter distance D A provided by two galaxy cluster samples compiled by De Filippis et al. (the elliptical β model) and Bonamente et al. (the spherical β model), and the luminosity distance D L from Constitution and Union2 type Ia supernova (SNe Ia) datasets. To obtain D L associated with the observed D A at the same redshift, we smooth the noise of the SNe Ia in a model-independent way, obtain the evolutionary curve of D L and, finally, test the DD relation. We find that the elliptical β model, when compared with the SNe Ia from the Constitution compilation, is only consistent with the DD relation at the 3σ confidence level (CL), while the spherical β model is incompatible with the DD relation at the 3σ CL. For the Union2 compilation, the De Filippis and Bonamente samples are marginally compatible with the validity of the DD relation at the 1σ and 2σ CLs, respectively.

In this paper we investigate the mass defect and other gravitational effects in noncommutative Schwarzschild space-time obtained by considering particles as smeared objects. The effects of space-time noncommutativity on mass defect of a test particle and a homogeneous spherical shell are calculated. The NC corrections to gravitational redshift, and light-speed in Schwarzschild field are briefly discussed. The results show that the NC corrections have weakening action on these gravitational effects comparing with those in commutative cases.

In this paper, we study the growth index of matter density perturbations for the power law model in $f(T)$ gravity. Using the parametrization $\gamma(z)=\gamma_0+\gamma_1 {z\over 1+z}$ for the growth index, which approximates the real evolution of $\gamma(z)$ very well, and the observational data of the growth factor, we find that, at $1\sigma$ confidence level, the power law model in $f(T)$ gravity is consistent with the observations, since the obtained theoretical values of $\gamma_0$ and $\gamma_1$ are in the allowed region., Comment: 11 pages 4 figures

The growth of matter perturbations in the $f(R)$ model proposed by Starobinsky is studied in this paper. Three different parametric forms of the growth index are considered respectively and constraints on the model are obtained at both the $1\sigma$ and $2\sigma$ confidence levels, by using the current observational data for the growth factor. It is found, for all the three parametric forms of the growth index examined, that the Starobinsky model is consistent with the observations only at the $2\sigma$ confidence level., Comment: 15 pages, 5 figures

We study the linear growth of matter perturbations in the DGP model with the growth index $\gamma$ as a function of redshift. At the linear approximation: $\gamma(z)\approx\gamma_0+\gamma_0^\prime z $, we find that, for $0.2\leq\Omega_{m,0}\leq0.35$, $\gamma_0$ takes the value from 0.658 to 0.671, and $\gamma_0^\prime$ ranges from 0.035 to 0.042. With three low redshift observational data of the growth factor, we obtain the observational constraints on $\gamma_0$ and $\gamma_0'$ for the $\Lambda CDM$ and DGP models and find that the observations favor the $\Lambda CDM$ model but at the $1\sigma$ confidence level both the $\Lambda CDM$ and DGP models are consistent with the observations., Comment: 12 pages, 4 figuers, to appear in PLB

The unparticle has been suggested as a candidate of dark matter. We investigated the growth rate of the density perturbation for the unparticle dark matter in the flat Universe. First, we consider the model in which unparticle is the sole dark matter and find that the growth factor can be approximated well by $f=(1+3\omega_u)\Omega^{\gamma}_u$, where $\omega_u$ is the equation of state of unparticle. Our results show that the presence of $\omega_u$ modifies the behavior of the growth factor $f$. For the second model where unparticle co-exists with cold dark matter, the growth factor has a new approximation $f=(1+3\omega_u)\Omega^{\gamma}_u+\alpha \Omega_m$ and $\alpha $ is a function of $\omega_u$. Thus the growth factor of unparticle is quite different from that of usual dark matter. These information can help us know more about unparticle and the early evolution of the Universe., Comment: 6pages, 4 figures, accepted for publication in Eur. Phys. J. C

We study the dynamics of a phantom scalar field dark energy interacting with dark matter in loop quantum cosmology (LQC). Two kinds of coupling of the form $\alpha{\rho_m}{\dot\phi}$ (case I) and $3\beta H (\rho_\phi +\rho_m)$ (case II) between the phantom energy and dark matter are examined with the potential for the phantom field taken to be exponential. For both kinds of interactions, we find that the future singularity appearing in the standard FRW cosmology can be avoided by loop quantum gravity effects. In case II, if the phantom field is initially rolling down the potential, the loop quantum effect has no influence on the cosmic late time evolution and the universe will accelerate forever with a constant energy ratio between the dark energy and dark matter., Comment: 18 pages, 7 figures, PRD published version

We study the Brownian motion of a charged test particle driven by quantum electromagnetic fluctuations in the vacuum region near a non-dispersive and non-absorbing dielectric half-space and calculate the mean squared fluctuations in the velocity of the test particle. Our results show that a nonzero susceptibility of the dielectrics has its imprints on the velocity dispersions of the test particles. The most noteworthy feature in sharp contrast to the case of an idealized perfectly conducting interface is that the velocity dispersions in the parallel directions are no longer negative and does not die off in time, suggesting that the potentially problematic negativeness of the dispersions in those directions in the case of perfect conductors is just a result of our idealization and does not occur for real material boundaries., Comment: 9 pages, no figures, Revtex4

A novel Static Synchronous Compensator (STATCOM) for high-voltage, high-power is proposed in this paper. The STATCOM proposed is constructed by cascading several three-phases Voltage Source Inverters (VSI) with individual DC capacitor. A control method for DC voltages regulation and equalization is developed to deal with VSI-parameter-difference which is prone to make DC voltage unbalanced. A so-called phase-shifted sinusoidal pulse-width-modulation (PS-SPWM) switching scheme is applied to control the switching device of each three-phases VSI, which can reduce the switch frequency without degrading the character of the output current. Single phase transformers are essential to make three-phases VSIs cascading possible. However, the capability of the transformers is far less than that of compensator. Compared to STATCOM based on single-phase VSI cascading, the proposed compensator has fewer DC capacitors, fewer switch-devices and lower DC voltage ripple. Moreover, fast response of the compensator is also achieved by applying dq decoupled currents control method in synchronous frame. Simulation results not only verify the validity and feasibility of the proposed STATCOM but also show that control method employed can maintain the DC voltages stable and equalizing.

A novel control method for D-STATCOM under unbalanced condition is proposed in this paper. In the proposed method, the load and the compensator are taken as a whole comprehensive load, and the control object is that the line side only provides positive sequence active currents. The control scheme proposed is made up of DC voltage controller and current controller. The former mainly maintains the voltage of DC-capacitor at a desire value. The latter based on source currents detection, which has a close-loop structure, is presented in `dq' reference frame. In the current controller, the reference of d-axis is provided by DC voltage controller and the reference current of q-axis is zero. So the control method proposed omits complicated load reactive current extraction which generates reference value for currents tracking controller in traditional control method based on load currents detection. It simplifies the control scheme. Compared to double `dq' decoupled control method usually used for D-STATCOM under unbalanced conditions, the control scheme has a simpler structure, less calculation and is more convenient to realize. Simulation results show that D-STATCOM applying proposed control method can achieve good performance under unbalanced conditions.

The effect of spatial curvature in reconstructing the cosmic expansion history and the property of dark energy is studied in this paper by smoothing the noise of the Union2.1 Type Ia Supernovae (SNIa) data with a Gaussian smoothing function. We find that the spatial curvature induces an apparent effect in reconstructing the Hubble parameter H(z), the deceleration parameter q(z), and especially on the equation of state w(z) of dark energy. Thus, when one probes the dark energy property, an assumption of a flat universe may induce critical bias and it is imperative to take account of the spatial curvature.

We propose a parametrization for the growth index of the linear matter perturbations, $\gamma(z)=\gamma_0+\frac{z}{1+z}\gamma_1$. The growth factor of the perturbations parameterized as $\Omega_m^{\gamma}$ is analyzed for both the $w$CDM model and the DGP model with our proposed form for $\gamma$. We find that $\gamma_1$ is negative for the $w$CDM model but is positive for the DGP model. Thus it provides another signature to discriminate them. We demonstrate that $\Omega_m^{\gamma}$ with $\gamma$ taking our proposed form approximates the growth factor very well both at low and high redshfits for both kinds of models. In fact, the error is below 0.03% for the $\Lambda$CDM model and 0.18% for the DGP model for all redshifts when $\Omega_{m0}=0.27$. Therefore, our parametrization may be robustly used to constrain the growth index of different models with the observational data which include points for redshifts ranging from 0.15 to 3.8, thus providing discriminative signatures for different models., Comment: 14 pages, 6 figures; Added references