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Design of experiment (DoE) techniques have been widely used in the field of chromatographic parameters optimization as a valuable tool. A systematic literature review of the available DoE techniques applied to the development of a chromatographic analysis method is presented in this paper. First, the most common available designs and the implementation steps of DoE are comprehensively introduced. Then the studies in recent 10 years for the application of DoE techniques in various chromatographic techniques are discussed, such as capillary electrophoresis, liquid chromatography, gas chromatography, thin-layer chromatography, and high-speed countercurrent chromatography. Current problems and future outlooks are finally given to provide a certain inspiration of research in the application of DoE techniques to the different chromatographic techniques field. This review contributes to a better understanding of the DoE techniques for the efficient optimization of chromatographic analysis conditions, especially for the analysis of complex systems, such as multicomponent drugs and natural products.

ObjectivesMental health problems among university students are a cause of widespread concern. Mindfulness-based interventions (MBIs) delivered online have considerable potential to help university students manage mental health challenges. However, there is no consensus regarding the efficacy of online MBIs. This meta-analysis aims to determine whether MBIs are feasible and effective for improving university students’ mental health.MethodsRandomised controlled trials (RCTs) in Web of Science, PubMed, Cochrane Library, Embase and the US National Library of Medicine (Clinical Trial Registry) published through August 31, 2022, were searched. Two reviewers selected the trials, conducted a critical appraisal, and extracted the data. Nine RCTs met our inclusion criteria.ResultsThis analysis showed that online MBIs were effective in improving depression (standardised mean difference [SMD] = −0.27; 95% confidence interval [CI], −0.48 to −0.07; P = 0.008), anxiety (SMD = −0.47; 95% CI, −080 to −0.14; P = 0.006), stress (SMD = −0.58; 95% CI, −0.79 to −0.37; P < 0.00001), and mindfulness (SMD = 0.71; 95% CI, 0.17 to 1.25; p = 0.009) in university students. No significant effect was found on wellbeing (SMD = 0.30; 95% CI, −0.00 to 0.60; P = 0.05).ConclusionThe findings indicated that online MBIs could effectively improve the mental health of university students. Nevertheless, additional rigorously designed RCTs are required.Systematic review registrationhttps://inplasy.com/inplasy-2022-9-0099/, identifier INPLASY202290099.

A methane and coal dust explosion system was constructed to investigate the propagation of pressure and CO gas after methane and coal dust coupling explosion. The influence of coal dust concentration on the propagation of pressure and CO gas were analyzed by coupling explosion experiments of 5% methane with coal dust (0, 100 g/m3, 200 g/m3, 300 g/m3, 400 g/m3, and 500 g/m3), 7% methane with coal dust (0, 50 g/m3, 100 g/m3, 150 g/m3, and 200 g/m3), and 9% methane with coal dust (0, 50 g/m3, 100 g/m3, 150 g/m3, and 200 g/m3). The experimental results show that when 5% or 7% methane explodes with coal dust in the explosion chamber, the pressure first increases and then decreases with the increase of coal dust concentration. When the methane concentration is 9%, the pressure decreases with the increase of coal dust concentration. In the propagation pipe, the explosion pressure and CO gas concentration decrease with the increase of distance. When the methane concentration and distance are constant, the higher the coal dust concentration is, the higher the pressure and CO gas concentration is.

We propose to suppress high-power microwave pulses (HPMPs) using nonlinear dispersion and filtering natures of spoof surface plasmon polaritons (SSPPs). Frequency components of a short HPMP are distributed in time domain due to different group velocities and partly cutoff on SSPP transmission lines, leading to peak suppression of HPMP. To illustrate the protection mechanism in real microwave engineering, an SSPP mono-pulse antenna is designed. Sum and difference beam functions of the antenna are demonstrated by both simulations and experiments. For easy comparison, a microstrip mono-pulse antenna is also fabricated. HPMP incidences from the main lobe directions of the sum beam and difference beam are considered. Compared to the microstrip antenna, obvious suppression of HPMPs is observed in the SSPP mono-pulse antenna in different cases, which verifies the better performance to prevent HPMP damages by SSPPs. The proposed technology to suppress HPMPs by using SSPPs can find wide applications in radar and communication systems in the electronic warfare environment.

A challenge for frequency-reconfigurable antennas is how to realize miniaturized structures while preserving satisfying radiation performance in whole operation bandwidth. To address this problem, we apply planar periodic slow-wave structure (PSWS) with controlled dispersion features for miniaturization of antenna. Due to the subwavelength property and large propagation constant, this design holds a much more compact size than conventional microstrip structures. The proposed antenna consists of a double-layered dielectric substrate with the tunable patch on the top and a bias network combining with the feeding part on the bottom. The operating frequency is electronically controlled by the varactors shortened to the ground on nonradiating edges. It ranges from 4.87 to 5.52 GHz when the bias voltage varies from 9 to 16 V. Both simulated and measured results show that the proposed antenna maintains acceptable gains and similar radiation patterns while shrinking the size effectively. The proposed miniaturized and frequency-reconfigurable antenna holds potential applications in the ultracompact frequency hopping communication systems.

Safety issues are a major concern for the long-term maintenance and operation of utility tunnels, of which the focal point lies in the reliability of critical facilities. Conventional evaluation methods have failed to reflect the time-dependency and objectivity of the reliability of critical facilities, hence reducing the credibility of the analysis results and posing serious risks to the safety of utility tunnels. Taking joint waterproof facilities as an example, this paper focuses on the scientific problem of how to achieve a dynamic estimation of the reliability of critical facilities throughout the project life cycle of utility tunnels. To this end, an improved Weibull distribution model is proposed to incorporate the actual field conditions that affect the reliability of joint waterproof facilities of utility tunnels. Bayesian methods and Hamiltonian Monte Carlo methods are used to realize the posterior estimation of the model parameters via the observed failure data. The case study shows that the posterior prediction results fit well with the actual observation data. The proposed model can be used to estimate in real time such key reliability indicators as failure rate, failure warning time and expected failure time, which facilitate the safe operation and targeted maintenance of utility tunnels.

We propose a method to construct the broadband 90° balun with low-phase-imbalance performance based on a U-shaped periodic slow wave structure (PSWS) transmission line (TL), whose dispersion curve has a linear region in a wide frequency band. By introducing meander lines and U-shaped TLs, the linearity, cutoff frequencies and slope of dispersion curves of PSWS can be controlled flexibly. Simulated and measured results show good agreements. Both reflection coefficient and isolation of the proposed balun are below −15 dB from 1.5 to 2.0 GHz. The phase deviation is within ±3°, covering a fractional bandwidth of 28.6%. Compared with that based on the traditional corrugated periodic slow wave TL unit, the operating bandwidth of the proposed balun is increased by more than six times. Moreover, the proposed PSWS keeps excellent ability of field confinement and therefore improves the isolation between the output ports. In a word, based on the proposed method, the microwave devices and circuits which realize the function of phase shifting can be designed.

Heat stress (HS) affects the development of porcine gametes and embryos negatively, induces the decrease of reproductive ability significantly, threatens global pig production. Ginsenoside Re (GRe), is a main bioactive component of ginseng, shows very specific anti-apoptotic, antioxidant and anti-inflammatory activities. To investigate the alleviating effect of GRe on the in vitro maturation of porcine oocyte under the HS, the polar body extrusion rate, intracellular levels of reactive oxygen species (ROS) and glutathione (GSH), ATP content, mitochondrial membrane potential (MMP) were assessed. For the current study, porcine cumulus-oocyte complexes (COCs) randomly divided into four groups: the control, GRe, HS and HS + GRe group. The results showed that HS inhibited the cumulus cell expansion and polar body extrusion rate, the levels of GSH and MMP, the ATP content, the gene expression of Nrf2 of porcine oocytes and the parthenogenetic activation (PA) embryo development competence, but GRe treatment could partly neutralize these adverse effects. Furthermore, HS increased the ROS formation and percentage of apoptosis, the gene expression of HSP90, CASP3 and CytoC of porcine oocytes, but GRe could weaken the effect on Cyto C and BAX expression induced by HS. Taken together, these results showed that the presence of GRe during in vitro maturation protects porcine oocytes from HS. These findings lay a foundation for GRe may be used as a potential protective drug to protect porcine oocytes against HS damage.

The utilization of urban underground space (UUS) offers an effective solution to urban problems but may also negatively affect urban development. Therefore, UUS development needs better concerted guidelines to coordinate various urban systems and the multiple components of the underground world. Sustainable Development Goals (SDGs), which should be viewed as important yardsticks for UUS development, do not explicitly mention urban underground space, although many of them are affected by both the positive and negative consequences of its development. To fill this gap, this review lays the foundations of relevant UUS concepts and uses exemplary cases to reveal that 11 out of 17 SDGs can be linked with UUS uses. These linkages also manifest that land administration, integrated planning, architectural design, and construction technology are critical dimensions for increasing the contributions of UUS to the realization of SDGs. To achieve multi-disciplinary synergies among these four critical dimensions, a collaborative approach framework based on spatial data infrastructure is required. Thus, this work provides academics and practitioners with a holistic view of sustainable UUS development.

Objectives to evaluate three-dimensional postsurgical stability of surgery-first approach with 2-jaw surgery and maxillary premolar extraction in skeletal class III patients and excavate factors influencing the relapse. Material and methods 24 patients were enrolled in this prospective cohort study. Serial cone-beam computer tomography images were superimposed and measured the surgical stability at the presurgical examination, 1 week, 3 month, 6 month and 12 month postoperatively. Patients were grouped by the amount of mandible sagittal relapse(stable group, n = 8; highly unstable group, n = 7). Skeletal and dental morphological variables, the amount of surgical changes, and orthodontic-related variables were compared between groups and analyzed for correlations with postsurgical stability. Results Considerable amount of pronation relapse on mandible were within three month postoperatively. The maxilla remained clinically stable. The coronoid process height, posterior maxillary height, the mandibular setback, distal segment intraoperative rotation and the amount maxillary second molar orthodontic intrusion showed significant difference between groups. The above variables, mandibular height, occlusal vertical dimension, and the mandibular and anterior maxillary intraoperative descent were significantly correlated with postoperative instability. Conclusions Mandibular pronation relapse mainly in the first three months after surgery.The maxilla postsurgical position is clinically stable. The factors for instability in the surgery-first approach include a longer coronoid process, longer facial height, a wider occlusal vertical dimension, greater surgical setback and descent, and more maxillary second molar intrusion. Clinical relevance Results can provide reference for patient selection, surgical planning and preoperative dental alignment stimulation for surgery-first approach. Trial Registration ChiCTR2200055787

Crosstalk noise suppression is a crux in the high-speed integrated circuit design, which requires weak-coupling between transmission lines (TLs) over a wide band. To overcome the difficulty, this article presents a novel method to suppress the broadband crosstalk noise between a single TL and the differential pair based on spoof surface plasmon polaritons (SPPs). Due to the subwavelength feature of spoof SPP TLs, a natural mode mismatching between the spoof SPP TL and conventional microstrip (MS) brings a broadband suppression of near-field coupling. In order to verify the crosstalk suppression effect, four different kinds of prototypes are discussed and compared. The simulated and measured results in the frequency domain and time domain demonstrate that the proposed scheme achieves more than 83% far-end noise peak suppression than the traditional MS technology by replacing the single MS TL to the spoof SPP TL. Accordingly, the time-domain crosstalk noise is significantly suppressed without any extra costs, demonstrating its potential applications in ultracompact high-speed integrated circuits.

Perfect lenses, superlenses and time-reversal mirrors can support and spatially separate evanescent waves, which is the basis for detecting subwavelength information in the far field. However, the inherent limitations of these methods have prevented the development of systems to dynamically distinguish subdiffraction-limited signals. Utilizing the physical merits of spoof surface plasmon polaritons (SPPs), we demonstrate that subdiffraction-limited signals can be transmitted on planar integrated SPP channels with low loss, low channel interference, and high gain and can be radiated with a very low environmental sensitivity. Furthermore, we show how deep subdiffraction-limited signals that are spatially coupled can be distinguished after line-of-sight wireless transmission. For a visualized demonstration, we realize the high-quality wireless communication of two movies on subwavelength channels over the line of sight in real time using our plasmonic scheme, showing significant advantages over the conventional methods., Surface plasmons open new channels for communication The unique properties of surface plasmons enable wireless transmission of signals separated by less than one wavelength. Until recently, it was considered impossible to distinguish signals with sub-wavelength separation, due to the so-called diffraction limit. This limit can be overcome using artificial structures called metamaterials, but it is difficult to integrate these new components with conventional electronics. Now, Tie Jun Cui at Southeast University in Nanjing, China, and co-workers have shown that sub-wavelength signals can be transmitted using surface plasmon polaritons (SPPs)—combinations of electromagnetic waves and charge motion that travel on the surface of a metal. By encoding signals in ‘spoof’ SPPs that mimic natural SPPs, the team were able to wirelessly transmit two high-definition movies on channels just one-tenth of a wavelength apart, even with a concrete wall in the way.

The high radiation resistance and long time stability of Gd2Zr2O7 ceramics make it a promising candidate for high level waste (HLW) immobilization materials. In this study, single phase nanocrystalline Gd2Zr2O7 was successfully synthesized and consolidated at temperatures around 1050 °C for only 1 min by flash sintering for the first time. The phase evolution and microstructural development during flash sintering were systematically studied and compared with the conventionally sintered samples. The flash sintered Gd2Zr2O7 exhibit defect fluorite structure, and a following heat treatment at 1400 °C could transform the Gd2Zr2O7 ceramics from defect fluorite phase into pyrochlore phase. The MCC-1 leaching test shows that the flash sintered Gd2Zr2O7 samples exhibit good aqueous durability.

We present a new method to design miniaturized antennas using a corrugated microstrip (CM) line, which shows good slow wave characteristic in the required frequency band. To achieve good radiating behavior and low profile simultaneously, CM is employed as the resonating part of the antenna. The impact of the CM propagation constant on the antenna is discussed in detail. The miniaturized antenna is designed and measured to verify the feasibility of the design method. The measured results show that the proposed antenna can achieve a beamwidth of 70° in E-plane and 75° in H-plane with a gain tolerance of 3 dB, and the realized peak gain level at the central frequency is 5.15 dBi, which have good agreements to the expected designs. Such results indicate that the proposed antenna exhibits excellent radiation characteristics at the resonant mode. The effective size of the proposed miniaturized antenna is $0.16\lambda _{0}\times 0.16 \lambda _{0}\times 0.04 \lambda _{0}$ at 9 GHz, in which $\lambda _{0}$ is the wavelength of the central frequency.

Background: Anthracyclines, including doxorubicin, are some of the most potent anticancer drugs available. However, the use of doxorubicin as a chemotherapeutic agent is severely hindered by dose-limiting toxicity, particularly cardiotoxicity, while degrading other organ systems. Despite years of use and the number of details published on this drug, the understanding of its cellular mechanisms remains limited. Method: Cardiomyocyte grouping was carried out, where H9C2 cardiomyocytes were randomly divided into a control group, a myocardial model group, an SP(Substance P) group, and an SP antagonist group. For replication in animal models, twelve rats were similarly randomly assigned into a control group, a myocardial model group, an SP group, and an SP antagonist group. Except for the control group, the rats in the other groups were modelled: the rats were injected with adriamycin solution. Flow cytometry was used to detect apoptosis, while HE(Hematoxylin and Eosin) staining, TUNEL(Terminal deoxynucleotidyl transferase dUTP nick end labeling) stain, Western Blot detection, and transmission electron microscopy were performed to detect autophagy levels accordingly. All the results were analysed and carefully interpreted. Results: The tachykinin, substance P, is located mainly in sensory nerves and in the heart, where substance P-containing nerve fibres are often found around coronary vessels, making them ideally situated to detect changes in the myocardial environment. Apoptosis and autophagy are genetically regulated, evolutionary-conserved processes that regulate cell fate and are important for development, normal physiology, and a wide range of diseases. Recent studies show that despite the significant differences between these two processes, their regulation is closely connected and certain regulators are able to control both apoptosis and autophagy.Conclusions: In this study, the influence of substance P was discussed, providing possible molecular mechanisms for crosstalk between apoptosis and autophagy mediating heart failure due to doxorubicin therapy. Trial registration: (20192BBGL7D031) 2019-09-17.

Due to the special geographical location and climate of China, there are large differences in the chemical composition and content of Paederia scandens (PS) from different origins, which will have a large impact on its efficacy.An efficient quality control method for PS was established by combining ultra-high-performance liquid chromatography (UPLC) and electrospray ionization mass spectrometry analyses. First, a UPLC-quadrupole time-of-flight mass spectrometry system was employed to identify the chemical composition of PS from seven different origins. Then, the chemical variation in 73 batches of PS samples was subsequently investigated by quantitation of four marker compounds.A total of 15 common compounds were identified in the samples of PS from seven origins. And four of the marker compounds were chosen based on VIP values to characterize the differences between PS samples of different origins. The linearity ranged between 0.005 and 2.500 mg/mL; the correlation coefficients (rThe results show that the method can be effective and comprehensive in evaluating the quality of PS from different origins. And this comprehensive strategy proved to be a powerful technique used to differentiate between different geographical herbs.

The present study determined five saponins in Xuesaitong Dropping Pills(XDP) by micellar electrokinetic chromatography(MEKC), and evaluated between-batch consistency by MEKC fingerprints and similarity analysis. A background buffer was composed of 20 mmol·L~(-1) sodium tetraborate-20 mmol·L~(-1) boric acid solution(pH 8.5), 55 mmol·L~(-1) sodium dodecyl sulfate(SDS), 23 mmol·L~(-1) β-cyclodextrin, and 13% isopropyl alcohol. All separations were performed at 25 ℃,20 kV and the detection wavelength was set at 203 nm. The separation channel was a fused silica capillary with a dimension of 75 μm I.D. and a total length of 50.2 cm(effective length of 40.0 cm). The contents of notoginsenoside R_1, and ginsenosides Rg_1, Re, Rb_1, Rd were determined with their quality control ranges set. The fingerprints of XDP were established and the between-batch consistency was evaluated by similarity analysis. The contents of five saponins from the 19 batches of XDP were stable in the fixed ranges. Statistical analysis was carried out on the results of multiple batches of samples, and the specific quality control ranges were recommended as follows: notoginsenoside R_1 21.92-34.16 mg·g~(-1), ginsenosides Rg_1 83.54-131.78 mg·g~(-1), ginsenosides Re 13.58-19.82 mg·g~(-1), ginsenosides Rb_1 89.40-129.90 mg·g~(-1), and ginsenosides Rd 22.34-35.67 mg·g~(-1). Eleven characteristic peaks were identified in the fingerprints. Five peaks, notoginsenoside R_1 and ginsenosides Rg_1, Re, Rb_1, Rd, were identified with reference standards. The similarities of the 19 batches of samples were all above 0.988, indicating good between-batch consistency. This method is green and simple, and can be used for the quantitative determination and quality evaluation of XDP. It can also provide references for the quality control of other Chinese medicinal dripping pills.