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Purpose. This study centers around the Wangzhanghe Country Park located in Jiaozuo City as the research object. Through analysis of the site’s evolution by GPS and its status-quo by GIS, the map of spatial distribution suitability has been illustrated. Design. Based on the major principle of achieving sustainable development of the ecosystem and the derived concept of building a diversified landscape, we have developed the overall scheme of planning and landscape layout of the country park. Specifically, the area of ecological restoration is further divided into the areas of quarry restoration, bare land restoration, slope protection, vegetation, and dam maintenance, and restorative measures are put forward accordingly. Findings. Our research findings indicate that thanks to the vegetation restoration of the side slope, the area of bare land in mountain farmland has been evidently reduced, whereas the severely damaged ash pits and green spots have also been restored. Originality: in the meantime, we have leveraged the flat space at the foot of the mountain to foster a viewing experience and provide recreational activities for citizens, so that they are able to effectively increase their access to outdoor events and improve their sense of engagement and experience in the events, thereby providing a reference for building a green, diverse, and sustainable system of ecological services for the urban country park.

Estrogen and progesterone are the primary female sex hormones and have net excitatory and inhibitory effects, respectively, on neuronal function. Fluctuating concentrations across the menstrual cycle has led to several lines of research in relation to neuromuscular function, yet evidence from animal and cell culture models have yet to be demonstrated in human motor units (MU) coupled with quantification of circulating hormones.Intramuscular electromyography (iEMG) was applied to record MU potentials (MUP) and corresponding MUP trains (MUPT) from the vastus lateralis of eumenorrheic females during the early follicular, ovulation and mid luteal phases of the menstrual cycle, alongside assessments of neuromuscular performance. Multi-level regression models were applied to explore effects of time and of contraction level. Statistical significance was accepted as pKnee extensor maximum voluntary contraction (MVC), jump power, force steadiness, and balance did not differ across the menstrual phases (all p>0.4). Firing rate of low threshold MU (10% MVC) was reduced during phases of high progesterone (β=-0.82Hz, p0.3).Assessments of neuromuscular performance did not differ across the menstrual cycle. The suppression of low threshold MU firing rate during periods of increased progesterone may suggest a potential inhibitory effect and an alteration of recruitment strategy, however this had no discernible effect on performance. These findings highlight contraction level dependent modulation of VL MU function over the eumenorrheic cycle.

Long-term exercise training has been considered as an effective strategy to counteract age-related hormonal declines and minimise muscle atrophy. However, human data relating circulating hormone levels with motor nerve function are scant. The aims of the study were to explore associations between circulating sex hormone levels and motor unit (MU) characteristics in older men, including masters athletes competing in endurance and power events. Forty-three older men (mean ± SD age: 69.9 ± 4.6 years) were studied based on competitive status. The serum concentrations of dehydroepiandrosterone (DHEA), total testosterone (T) and estradiol were quantified using liquid chromatography mass spectrometry. Intramuscular electromyographic signals were recorded from vastus lateralis (VL) during 25% of maximum voluntary isometric contractions and processed to extract MU firing rate (FR), and motor unit potential (MUP) features. After adjusting for athletic status, MU FR was positively associated with DHEA levels (p = 0.019). Higher testosterone and estradiol were associated with lower MUP complexity; these relationships remained significant after adjusting for athletic status (p = 0.006 and p = 0.019, respectively). Circulating DHEA was positively associated with MU firing rate in these older men. Higher testosterone levels were associated with reduced MUP complexity, indicating reduced electrophysiological temporal dispersion, which is related to decreased differences in conduction times along axonal branches and/or MU fibres. Although evident in males only, this work highlights the potential of hormone administration as a therapeutic interventional strategy specifically targeting human motor units in older age.

Although muscle atrophy may partially account for age-related strength decline, it is further influenced by alterations of neural input to muscle. Persistent inward currents and the level of common synaptic inputs to motoneurons influence neuromuscular function. However, these have not yet been described in aged human quadriceps.High density surface electromyography (HDsEMG) signals were collected from the vastus lateralis of 15 young (mean±SD, 23 ± 5 y) and 15 older (67 ± 9 y) men during submaximal sustained and 20-s ramped contractions. HDsEMG signals were decomposed to identify individual motor unit discharges, from which delta F and intramuscular coherence were estimated.Older participants produced significantly lower knee extensor torque (pPersistent inward currents and common synaptic inputs are lower in the vastus lateralis of older males when compared to young. These data highlight altered neural input to the clinically and functionally important quadriceps, further underpinning age-related loss of function which may occur independently of the loss of muscle mass.Key PointsThe age-related loss of muscle mass is exceeded by the loss of function, which is influenced by structural and functional alterations of the nervous system.Motoneuronal persistent inward currents and common synaptic inputs play an important role in the activation of motor units and subsequent force generation and control ability.Here we show reduced estimates of persistent inward currents and lower common synaptic inputs to older vastus lateralis, potentially contributing to observed lower strength and poorer force tracking.These findings highlight decrements of the aged human motor system, accompanied by muscle atrophy in functionally relevant muscle groups, which should be considered in the application of interventions targeting aged human muscle.

In this paper, we propose and demonstrate a novel, to the best of knowledge, filter-free photonics-assisted microwave frequency translator with a tunable phase shift and amplitude. The pivotal component of the proposed scheme is an integrated dual-polarization quadrature phase shift keying (DP-QPSK) modulator, which is applied to generate a polarization orthogonal carrier-suppressed single sideband modulation signal and frequency shifted optical carrier signal. The polarization-multiplexed optical signal outputs from the DP-QPSK modulator is then sent to a photodetector (PD) via a polarization controller (PC) and a polarizer to implement photoelectric conversion. The electrical signal output from the PD is the desired frequency translated microwave signal, and the amount of frequency shift is determined by the frequency of the sawtooth wave applied to the DP-QPSK modulator. In addition, since the PC can be used to adjust the polarization angle and introduce a phase difference between the two orthogonally polarized optical signals, the phase shift and amplitude of the obtained translated signal can also be easily tuned. A theoretical analysis and simulation experiment are carried out to verify the feasibility of the proposed scheme. The simulation results show that the novel scheme can realize frequency translation with a 360° continuously tunable phase shift and adjustable amplitude for both a single-tone signal and linearly frequency modulated signal with a 50 MHz bandwidth. The spurious suppression ratios of the single-tone signal and LFM signal after frequency translation are larger than 48 and 30 dB, respectively.

Radiomics has potential advantages in the noninvasive histopathological and molecular diagnosis of gliomas. We aimed to develop a novel image signature (IS)-based radiomics model to achieve multilayered preoperative diagnosis and prognostic stratification of gliomas. Herein, we established three separate case cohorts, consisting of 655 glioma patients, and carried out a retrospective study. Image and clinical data of three cohorts were used for training (N = 188), cross-validation (N = 411), and independent testing (N = 56) of the IS model. All tumors were segmented from magnetic resonance (MR) images by the 3D U-net, followed by extraction of high-throughput network features, which were referred to as IS. IS was then used to perform noninvasive histopathological diagnosis and molecular subtyping. Moreover, a new IS-based clustering method was applied for prognostic stratification in IDH-wild-type lower-grade glioma (IDHwt LGG) and triple-negative glioblastoma (1p19q retain/IDH wild-type/TERTp-wild-type GBM). The average accuracies of histological diagnosis and molecular subtyping were 89.8 and 86.1% in the cross-validation cohort, while these numbers reached 83.9 and 80.4% in the independent testing cohort. IS-based clustering method was demonstrated to successfully divide IDHwt LGG into two subgroups with distinct median overall survival time (48.63 vs 38.27 months respectively, P = 0.023), and two subgroups in triple-negative GBM with different median OS time (36.8 vs 18.2 months respectively, P = 0.013). Our findings demonstrate that our novel IS-based radiomics model is an effective tool to achieve noninvasive histo-molecular pathological diagnosis and prognostic stratification of gliomas. This IS model shows potential for future routine use in clinical practice.

Due to their low cost, tunable band gap and excellent thermostability, all-inorganic halide perovskites CsPbX

In this paper, we study the stability and bifurcation behavior of a three-dimensional melanoma model with immune response. The system has at least one and at most three positive equilibria. It is proved that the system undergoes Hopf bifurcation and saddle-node bifurcation at the positive equilibrium. We investigate the direction of Hopf bifurcation and stability of the bifurcating periodic solution by center manifold theorem and normal form theory. Moreover, codimension two bifurcations of the system are analyzed. We demonstrate the existence of Bautin bifurcation and Bogdanov–Takens bifurcation of the system. The normal form of Bautin bifurcation and Bogdanov–Takens bifurcation are given. Finally, some numerical simulations are demonstrated to support our theoretical results, and the importance of some parameters of the system is discussed, in particular the activation rate of CD8[Formula: see text]T cells.

With the increasing demand for near-infrared (NIR) detection in the fields of automation, military industry, communications and medical health, how to develop novel high quality and low cost NIR photodetectors has become a research hotspot in recent years. In order to solve the problems such as expensive raw materials, complex production equipment and difficulty in integration of traditional III–V semiconductors, PbS quantum dots (QDs) have become the most promising emerging nanomaterials for commercial NIR detection due to their excellent light absorption performance, low cost, simple deposition process and tunable band gap. This review summarizes the development strategies of PbS QD-based photodetectors over the past, focusing on the performance of devices with different structures and the feasibility of commercialization. In order to meet the needs of modern industry for NIR detection and realize commercialization, PbS QD-based photodetectors need to make breakthroughs in detection performance, device stability, device integration and large-scale preparation. These contents are discussed in detail in this paper. By comparing different strategies, the deficiencies of PbS QD-based photodetectors are proposed, and it is hoped that it can provide a reference for the further development of PbS QD-based photodetectors.

Recently, perovskite nanocrystals (NCs) have become highly promising materials due to their unique optical and electrical properties such as high absorption coefficient, high photoluminescence quantum yield, and long exciton diffusion length. It is well known that the band gap of perovskite nanocrystals can be tuned by composition engineering, ranging from the ultraviolet to near-infrared regions. Moreover, thanks to the solution-processing feature, perovskite NCs have become much popular for various photodetectors. Hence, in this review, we carefully introduce the developmental progress of perovskite NCs and photodetectors, including the aspects of synthetic procedures, device architectures, working mechanism, and optimization procedures. Besides, great achievements and challenges, in terms of the high photosensitivity and detectivity, are also discussed for perovskite NC-based photodetectors. Finally, the application perspective of next generation photodetectors is prospected, which provides a reference for the related study.

The photoinduced phase segregation (PIPS) of mixed-halide perovskites (MHPs), due to halogen migration, has reaped considerable attention for its retroaction on film photostability and photovoltaic...

Nickel oxide (NiOx) film is employed to replace PEDOT:PSS as the hole transport layer for the inverted perovskite solar cells (PSCs) with Zinc Oxide as electron transport layer, and we focus on the...

Aim: Despite males typically exhibiting greater muscle strength and fatigability than females, it remains unclear if there are sex-based differences in neuromuscular recruitment strategies e.g. recruitment and modulation of motor unit firing rate (MU FR) at normalized forces and during progressive increases in force. Methods: The study includes 29 healthy male and 31 healthy female participants (18-35years). Intramuscular electromyography (iEMG) was used to record individual motor unit potentials (MUPs) and near-fibre MUPs from the vastus lateralis (VL) during 10% and 25% maximum isometric voluntary contractions (MVC), and spike-triggered averaging was used to obtain motor unit number estimates (MUNE) of the VL. Results: Males exhibited greater muscle strength (P

An approach for simultaneous modulation format identification (MFI) and optical signal-to-noise ratio (OSNR) monitoring in digital coherent optical communications is proposed based on optoelectronic reservoir computing (RC) and the signal’s amplitude histograms (AHs) obtained after the adaptive post-equalization. The optoelectronic RC is implemented using a Mach-Zehnder modulator and optoelectronic delay feedback loop. We investigate the performance of the proposed model with the number of symbols, bins of AHs and the hyperparameters of optoelectronic RC. The results show that 100% MFI accuracy can be achieved simultaneously with accurate OSNR estimation for different modulation formats under study. The lowest achievable OSNR estimation mean absolute errors for the dual-polarization (DP)-quadrature phase-shift keying signal, the DP-16-ary quadrature amplitude modulation (16QAM) signal, and the DP-64QAM signal are 0.2 dB, 0.32 dB and 0.53 dB, respectively. The robustness of the proposed scheme is also evaluated when the optoelectronic RC is in presence of additive white Gaussian noises. Then, a proof of concept experiment is demonstrated to further verify our proposed method. The proposed approach offers a potential solution for next-generation intelligent optical performance monitoring in the physical layer.

AimDespite men exhibiting greater muscle strength and fatigibility than women, it remains unclear if there are sex-based differences in muscle recruitment strategies e.g. motor unit (MU) recruitment and modulation of firing rate (FR) at normalised forces and during progressive increases in force.MethodsTwenty-nine healthy male and thirty-one healthy female participants (18-35 years) were studied. Intramuscular electromyography was used to record individual motor unit potentials (MUPs) and near fibre MUPs from the vastus lateralis (VL) during 10% and 25% maximum isometric voluntary contractions (MVC), and spike-triggered averaging was used to obtain motor unit number estimates (MUNE) of the VL. Multilevel mixed-effects linear regression models were used to investigate the effects of sex at each contraction level.ResultsMen exhibited greater muscle strength (pppp=0.062) and FR (p=0.031). However, both sexes showed similar increases in MU size and FR when moving from low-to mid-level contractions. There were no sex differences in any near fibre MUP parameters or in MUNE.ConclusionIn the vastus lateralis, women produce muscle force via different neuromuscular recruitment strategies to men which is characterised by smaller MUs discharging at higher rates. However, similar strategies are employed to increase force production from low to moderate contractions. These findings of similar proportional increases between sexes support the use of mixed sex cohorts in studies of this nature.Key pointsIncreases in muscle force production are mediated by motor unit (MU) recruitment, and MU firing rate (FR).Women are underrepresented in studies of human neuromuscular research and markedly differ to men in a number of aspects of neuromuscular function, yet little is known of the recruitment strategies of each.Here we demonstrate men and women have similar vastus lateralis MU number estimates, yet women recruit smaller MUs with higher FR than men at normalised contraction levels. However, increases in force are achieved via similar trajectories of MU recruitment and MU FR in men and women.Although men and women exhibit divergent neuromuscular recruitment strategies to achieve normalised forces, increases in force are achived similarly and support the inclusion of mixed sex cohorts in studies of this nature.

In this paper, we consider the dynamics of a diffusive predator-prey system with stage structure and strong Allee effect. The upper-lower solution method and the comparison principle are used in proving the nonnegativity of the solutions. Then the stability and the attractivity basin of the boundary equilibria are obtained, by which we investigated the bistable phenomena. The existence and local stability of the positive constant steady-state are investigated, and the existence of Hopf bifurcation is studied by analyzing the distribution of eigenvalues. On the center manifold, we studied the criticality of the Hopf bifurcation by the normal form theory. Some numerical simulations are carried out for illustrating the theoretical results.

The tunable bandgap of mixed-halide perovskites (MHPs) makes them suitable for high-performance single-junction photovoltaics (PVs), as well as wide-bandgap components for multi-junction (tandem) structures. However, the composition engineering of halide ions, an effective procedure to adjust the bandgap of MHPs for PVs, result in photoinstability in MHPs due to the photo-induced anion phase segregation (PIAPS) effect. Specifically, MHP materials experience an inevitable phase transition from homogeneous alloys to conjugated lower/higher-bandgap phases, that is, iodide/bromide (I/Br)-rich domains, upon exposure to light. Reasonably, the sub-bandgap trapping states can lead to film inhomogeneity and performance deterioration in PVs. Meanwhile, it has been widely proven that the PIAPS phenomenon, even though it is reversible, may limit the commercial integration of MHPs in tandem applications because of their unstable output. Hence, in this review, initially, we study, analyze, and explore the “fashionable” PIAPS phenomenon systematically. Then, the feasible protocols to stabilize MHP materials, especially based on their correlation with the inherent mechanism of the PIAPS phenomenon, are adequately exhibited to help researchers develop more suitable procedures for its suppression. Finally, we provide some potential research points to study the PIAPS phenomenon and stabilize MHPs for their future commercial applications.

The reversible activation process, which involves electron transfer from adjacent redox mediators to cofactors, the reversible chemical state change of cofactors, and the functional/structural change of redox mediators, is one of the most significant features of biological enzymes, and has inspired the design of homogeneous catalysts. However, for heterogeneous catalysts, such enzyme-like characteristics have been only observed in very few transition metal–organic frameworks (MOFs) and single copper atom incorporated TiO2 catalysts during dynamic photocatalytic processes, and have never been seen in industrially important visible light-driven narrow-band gap semiconductor catalysts. Herein, we first report on the design and synthesis of highly active CdS/Co–N redox catalysts through the pyrolysis of trithiocyanuric acid cadmium-cobalt (CdCoTMT) coordination polymers as single-source precursors, which exhibit a reversible photoactivation process. This unique design and synthetic strategy provide a platform that facilitates atomic-level anchoring control of cofactor transition metal atoms (Co2+ and Ni2+), reversible modulation of the macroscopic optoelectronic properties of CdS and enhancement of photocatalytic hydrogen evolution, promoting the practical application of conventional heterogeneous catalysts.

With the flourishing development of perovskite nanocrystals (NCs), there has been a significant increase in the photoelectric conversion efficiency of perovskite nanocrystalline solar cells over the last five years. The variable band gap and superior phase stability of perovskite NCs are desirable for photovoltaic applications. A well-performing open-circuit voltage of these devices has been reported, approaching 85% of their theoretical limits. However, the short carrier lifetime and high interface recombination jointly limit the short-circuit currents and fill factors of the devices. This review aims at presenting a description of the fundamentals, recent progress and perspectives of perovskite nanocrystalline solar cells, with a focus on improving the stability of high-performance devices. Challenges and strategies concerning the surface passivation of perovskite NCs and films are discussed. In addition, we provide an extensive overview of the latest cutting-edge research to promote charge transport and extraction, focusing on the energy band alignment of the perovskite absorber, charge transport layer and the interface layer. Device architectures for improving the device performance are described, including tandem solar cells and gradient-bandgap multilayer solar cells. Finally, perspectives and undergoing efforts for the further development of perovskite nanocrystalline solar cells are presented.

Picea wilsonii is widely used for a forestation and landscaping in China. However, the molecular mechanisms underlying abiotic stress tolerance in this species remain elusive. In this study, we examined the transcriptomic changes induced by drought and salt stress in 8-week-old seedlings of P. wilsonii via RNA-Seq analysis; seedlings grown under normal conditions (without abiotic stress) served as a control. Approximately 36.26 Gb of transcriptome data were obtained from the three treatments. A total of 4171 (2579 up-regulated and 1732 down-regulated) and 3438 (1592 up-regulated and 1706 down-regulated) differentially expressed genes were identified under drought and salt treatments, respectively. Both RNA-Seq and qRT-PCR analyses showed that the expression of PwNAC genes, including PwNAC11, 24, 36, 38, 45, 47, 51 and 52, was greatly induced not only by salt stress but also by drought treatment, suggesting that these genes are involved in both salt and drought stress resistance in P. wilsonii. This is the first report of the transcriptome analysis of P. wilsonii. Our data will serve as a valuable genomic resource for the further characterization of the molecular mechanisms underlying abiotic stress tolerance in P. wilsonii.

We analyze the stability of positive equilibrium in a predator-prey model with time delay τ and subsidies. The sufficient conditions of the local Hopf bifurcations at the positive equilibrium are obtained. By center manifold theorem and normal form theory, we analyze the direction of Hopf bifurcations and stability of the bifurcating periodic solution. Using the global Hopf bifurcation theorem, we find that each connected component is unbounded. High-dimensional Bendixson theorem is used to prove that the system has no nonconstant periodic solutions of τ-period, then we obtain the global existence of periodic solutions. Finally, a numerical example is performed to support the theoretical results, and the effect of the food subsidy is discussed. We find that the food subsidy will make the stable interval $[0,\tau _{0})$ of positive equilibrium larger with $\tau _{0}$ the first Hopf bifurcation value.

Microbial antagonists are effective and environmentally friendly in controlling postharvest diseases of fruit. The present study investigated the influence of D. nepalensis on epiphytic microbiome and postharvest decay of jujube. Results showed that D. nepalensis notably reduced fungal decay, maintained the fruit firmness and delayed discoloration. The epiphytic microbiome revealed that D. nepalensis changed the fungal communities, but few influence on bacterial communities were observed. D. nepalensis, as the dominant population in the treatment group, decreased the abundance of pathogenic fungi of Alternaria, Penicillium, Fusarium and Botrytis, while increased the beneficial bacteria of Pantoea. The canonical correspondence analysis revealed that Debaryomyces was negatively correlated with the decay rate, whereas Penicillium, Acremonium, Rhodosporidiobolus and Hansfordia were positively correlated. In conclusion, D. nepalensis altered the successional process of fungal and bacterial communities to reduce the decay rate of jujube during storage.

Long-term exercise training has been considered as an effective strategy to counteract age-related hormonal declines and minimise muscle atrophy. However, human data relating circulating hormone levels with motor nerve function are scant. The aims of the study were to explore associations between circulating sex hormone levels and motor unit (MU) characteristics in older men, including masters athletes competing in endurance and power events. Forty-three older men (mean ± SD age: 69.9 ± 4.6 years) were studied based on competitive status. The serum concentrations of dehydroepiandrosterone (DHEA), total testosterone (T) and estradiol were quantified using liquid chromatography mass spectrometry. Intramuscular electromyographic signals were recorded from vastus lateralis (VL) during 25% of maximum voluntary isometric contractions and processed to extract MU firing rate (FR), and motor unit potential (MUP) features. After adjusting for athletic status, MU FR was positively associated with DHEA levels (p = 0.019). Higher testosterone and estradiol were associated with lower MUP complexity; these relationships remained significant after adjusting for athletic status (p = 0.006 and p = 0.019, respectively). Circulating DHEA was positively associated with MU firing rate in these older men. Higher testosterone levels were associated with reduced MUP complexity, indicating reduced electrophysiological temporal dispersion, which is related to decreased differences in conduction times along axonal branches and/or MU fibres. Although evident in males only, this work highlights the potential of hormone administration as a therapeutic interventional strategy specifically targeting human motor units in older age.

A switchable down-, up- and dual-chirped microwave waveform generation technique with improved time–bandwidth product (TBWP) is proposed and demonstrated based on a dual-polarization dual-parallel Mach–Zehnder modulator (DP-DPMZM) cascaded with a polarization modulator (PolM). By properly controlling the phase shifts of the radio frequency signals applied to the DP-DPMZM, switchable down-, up- and dual-chirped waveforms with simultaneous frequency and bandwidth doubling can be generated. To enlarge the TBWP further, splitting parabolic signal and phase-encoding splitting parabolic signal are used to drive the PolM for the enhancement of bandwidth and time duration. Numerical results demonstrate the generation of down-, up- and dual-chirped microwave waveform with TBWP of 8, 160 and 10240. The proposed method may find applications in future multifunction radar systems due to the high performance and flexibility.

Low temperature derived carbon electrodes are employed to fabricate low cost hole transport layer free perovskite solar cells, in which perovskite films annealed in glovebox and ambient air are used as the absorbers, respectively. Results suggest that the air annealed sample has bigger crystal grains and higher crystallinity, and the existence of a small amount of lead iodide which passivates grain boundaries contributes to a lower trap density. As a result, a maximum power conversion efficiency (PCE) of 13.07% was obtained on the air annealed device, which is higher than those of devices annealed in glovebox (11.25%). Furthermore, the stability of unencapsulated devices stored in wet (with humidity around 90% ± 5%) air atmosphere are investigated and the results prove that our devices exhibit good stability. In addition to rigid devices, flexible perovskite solar cells are also fabricated using the same procedure. The highest PCE of 11.53% is demonstrated on the champion flexible device, and 69% of its initial PCE can be maintained even after 2000 bending cycles with a bending radius of 2 mm. Our work provides a promising and simple rout for low-cost, air-stable, high-efficiency carbon perovskite solar cells for both large area production and flexible electronic devices industry.

Objectives: This study explored and analyzed the healing effect of Qinglong tail-wagging acupuncture method in therapy of knee osteoarthritis and its influence on inflammatory factors. Methods: 93 elderly patients with acute onset of knee osteoarthritis that hospitalized from March 2017 to June 2019 were admitted and randomly separated into observation group (n=48) and control group (n=45) in line with the method of random data form. The control group was given conventional electro-acupuncture, and the observation group was treated with the qinglong tail-waving acupuncture method. The clinical efficacy, pre- and post-VAS score, Lequesne and WOMAC indexes, and changes in serum inflammatory factor levels pre-and-post treatment were compared between the two sets of subjects. Results: The overall response rate of clinical treatment in observation group was remarkably higher than that of the control group (P < 0.05). Besides, the VAS, Lequesne as well as WOMAC scores of two groups after treatment were significantly reduced than those in pre-treatment (P < 0.05), and the indexes in observation group were remarkably lower than those in control group (P < 0.05). In addition, the serum IL-6, NO and TNF-α concentration of the two sets of subjects in post-treatment reduced significantly than that in pre-treatment (P < 0.05), and the serum IL-6, NO and TNF-α concentration in observation group were remarkably decreased than those in control group (P < 0.05). Conclusion: The acupuncture method of Qinglong tail-wagging has good healing effect on remedy of elderly knee osteoarthritis. The curative method is able to improve the patients’ function of knee joint and reduce the concentration of serum inflammatory factor in patients with knew osteoarthritis.

The photoinduced phase segregation (PIPS) of mixed-halide perovskites (MHPs), due to halogen migration, has reaped considerable attention for its retroaction on film photostability and photovoltaic output. Nevertheless, the original mechanism is still unclear. Herein, taking the representative CsPbIBr

Devices with printable carbon electrodes are promising directions for the commercialization of perovskite solar cells. Most of perovskite solar cells employ mesoporous device structures when using printable carbon as the counter electrodes. Here, we carry a comparative study of planar and mesoporous perovskite solar cells with carbon electrodes. The device efficiency is significantly reduced from 11.37% to 5.27% when the mesoporous TiO2 film is removed from the device structure. Compared with the planar device, smaller carrier transport resistance and bigger carrier recombination resistance are demonstrated for the mesoporous device. Results suggest that the presence of mesoporous TiO2 enables an efficient electron extraction from the perovskite absorber, which remits the serious carrier recombination in the hole transport layer free device due to the hole accumulation. Therefore, the electron extraction efficiency is crucial in these hole transport layer free devices with carbon electrodes. This study helps to develop further optimization of low temperature carbon-based perovskite solar cells for higher reproducibility and higher device performance.

We perform bifurcation analysis in a complex Ginzburg–Landau system with delayed feedback under the homogeneous Neumann boundary condition. We calculate the amplitude death region, and it turns out that the boundary of the amplitude death region consists of two Hopf bifurcation curves with wave number zero. The existence conditions for double Hopf bifurcations are established. Taking the feedback strength and time delay as bifurcation parameters, normal forms truncated to the third order at double Hopf singularity are derived, and the unfolding near the critical points is given. The bifurcation diagram near the double Hopf bifurcation is drawn in the two-parameter plane. The phenomena of amplitude death, the existence of stable bifurcating periodic solutions, and the coexistence of two stable periodic solutions with fast oscillation and slow oscillation respectively are simulated.

Trithiocyanuric acid trisodium salt hydrate (Na3TMT) has been proved an excellent heavy metal chelating agent and widely applied for heavy metal ions elimination in industrial wastewater. In this work, the chelating products of Bismuth(III) ion with this effective agent were prepared by solid state and liquid phase reactions, and proved as a new kind of n-type semiconductor. For full utilization of resource, the green and low-cost massive Bismuth chelate with good crystallinity, distinctive morphology, appropriate band structure and high stability was applied for photoelectrochemical application and photocatalytic organic pollutants degradation upon visible light. Results indicated that OH radicals were the main reactive specie in the photodegradation process. The combination of heavy metals and organic contaminants removal was achieved by a waste-to-wealth route.

Tin oxide (SnO2) has been confirmed as a vital electron transport material for efficient planar perovskite solar cells (PSCs) owing to its outstanding electrical and optical properties. Defectively, the SnO2 electron transport layer (ETL) by spin coating still remains great challenges for repeatable planar heterojunction PSCs fabrication for its limited scale and incompetent uniformity. Herein, the vacuum thermal-evaporation procedure is employed to achieve this intent by the dense and uniform SnO2 layer, which can largely improve the material utilization for cost reduction and act as a potential for the prospective industrial large-scale fabrication. Besides, a post-annealing treatment of evaporated SnO2 is proved obbligato to achieve an ideal crystallinity improvement. Furthermore, to remove the antisolvent method for perovskite, methyl ammonium acetate (MAAc) worked as an additive into the perovskite precursor for a pure MAPbI3 film to achieve the poisonous antisolvent free. Noticeable, the formation of an unstable MAPbI3-xAcx intermediate certainly has a great impact on the resulting perovskite, in which the particular surface-morphology was dominated by the MAAc volatilization rate. The obtained morphology with fluctuant pits and ridges, like a 3D-structure, contributes to more light absorption and contact area at perovskite/charge transport material interface, leading to higher photocurrent, more efficient charge extraction and better device performance. As a result, an optimal cell device can remain 86% of its initial photovoltaic performance (PCE: 16.79%) after a 50-d storage in air.

Double Hopf bifurcation analysis can be used to reveal some complicated dynamical behavior in a dynamical system, such as the existence or coexistence of periodic orbits, quasi-periodic orbits, or even chaos. In this paper, an algorithm for deriving the normal form near a codimension-two double Hopf bifurcation of a reaction–diffusion system with time delay and Neumann boundary condition is rigorously established, by employing the center manifold reduction technique and the normal form method. The dynamical behavior near bifurcation points are proved to be governed by twelve distinct unfolding systems. Two examples are performed to illustrate our results: for a stage-structured epidemic model, we find that double Hopf bifurcation appears when varying the diffusion rate and time delay, and two stable spatially inhomogeneous periodic oscillations are proved to coexist near the bifurcation point; in a diffusive Predator–Prey system, we theoretically proved that quasi-periodic orbits exist on two- or three-torus near a double Hopf bifurcation point, which will break down after slight perturbation, leaving the system a strange attractor.

We propose a novel technique for joint modulation format identification and frequency offset (FO) estimation. The linear frequency modulation signal which is obtained by a direct current signal and Fractional Fourier Transform (FrFT) is superimposed on the data symbols to mark and identify the modulation formats. Simulation results demonstrate our method can identify the DPBPSK, DPQPSK, DP8PSK, DP16QAM, DP32QAM and DP64QAM modulation formats correctly before chromatic dispersion compensation even the optical signal to noise ratio is extremely low. Additionally, due to the excellent time and frequency analysis properties of FrFT, the FO estimation range is greatly extended compared with the traditional Viterbi-Viterbi method.

Considering both the features of bandgap and stability, CsPbIBr2 presents a promising potential among the inorganic perovskite photovoltaic materials. Nevertheless, the poor quality films derived from the precursor solution acutely hinders the performance improvement of cells. Herein, high-quality CsPbIBr2 perovskite films are effectively fabricated through a facile one-step spin-coating method assisted by a preheating process. During spin coating, the reserved substrate heat accelerates solvent molecule volatilization, resulting in the complete coverage and enhanced crystallinity of the CsPbIBr2 films. Upon optimizing the substrate-preheating temperature precisely, perovskite solar cells (PSCs) with a configuration of ITO/SnO2/CsPbIBr2/spiro-OMeTAD/Ag exhibit a superior power conversion efficiency (PCE) of 9.86% with a stabilized output of 8.78% and an open-circuit voltage (Voc) of 1.267 V, all of which represent the excellent properties of the pure CsPbIBr2-based cells. Moreover, this work provides a promising route for the fabrication of inorganic perovskites.