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The global ecological environment is fragile, and large-scale coal mining has accelerated the loss of water resources, but it is difficult to quantify its impact. Studies have found that large-scale coal mining has a particularly large impact on the underflow zone of rivers, but blind mining affects environmental damage and loses the water volume of the river. The lack of a compensation mechanism for water damage caused by coal mining often exacerbates the province’s fragile water environment. This paper analyzes the prediction of the impact of coal mining on the underflow zone of the river. First of all, determine the mining area of the mine and collect and collect data. Then, the lost water volume was calculated as a predicted score using the double integro-differential equation. Finally, the GA-BiLSTM model is proposed to predict the lost water capacity. The experimental results show that the mean absolute error (MAE), root mean square (RMSE), and prediction pass rate are 11.78/%, 24.87/%, and 92/%, respectively, and the average relative error is only 9.98%. Compared with BP, SVM, LSTM, Bi-LSTM neural network model has better prediction accuracy. The experimental results also show that the model has good reliability and practicability, which can provide a new idea and method for the new analysis of the impact of coal mining on the underflow zone of the river.

Objective: To evaluate the anticancer activity of the natural diterpenoid lasiokaurin (LAS) against nasopharyngeal carcinoma (NPC) both in vitro and in vivo, along with investigating its underlying mechanism. Methods: MTT and colony formation assays were used to assess cell viability. Flow cytometry was utilized for the analysis of cell cycle arrest and apoptosis. Additionally, wound healing and transwell invasion assays were conducted separately to investigate cell migration and invasion. To uncover potential targets and pathways of LAS within NPC, a network pharmacological study based on RNA-sequencing (RNA-seq) was performed. Immunoblotting was subsequently used to determine protein levels. Furthermore, the anti-NPC activity of LAS was evaluated in vivo using a xenograft mouse model. Results: Based on in vitro investigations, it is evident that LAS exerted substantial inhibitory effects on NPC cells. Notably, LAS demonstrated significant reductions in cell viability, migration, and invasion capabilities, while simultaneously inducing apoptosis and G2/M cell cycle arrest. Furthermore, LAS suppressed the activation of MAPK, mTOR, STAT3, and NF-κB pathways within NPC cells. Additionally, in vivo experiments underscored LAS's capacity to attenuate NPC tumor growth without eliciting any discernible impact on body weight. Conclusion: Our data clearly demonstrate the anticancer activity of LAS against NPC, both in vitro and in vivo. These findings firmly position LAS as a potential candidate for the treatment of NPC.

In order to investigate the microwave vacuum drying characteristics of Lycium barbarum extract, the prediction model of drying kinetics of the relationship between its moisture ratio and drying time was established by investigating the influence rule of microwave power density and the initial relative density of the extract on the temperature, dry basis moisture content and water loss rate of the extract, and the model was validated. The experimental results showed that the microwave vacuum drying process of Lycium barbarum extract could be divided into two stages: The extract was transformed from a fluid state to a semi-fluid state (stage I) and from a semi-fluid state to a dry paste state (stage II). The higher the microwave power density and the initial relative density, the rising trend of the temperature of the extract seemed more obvious. The faster the water content of the dry base decreased, the greater the change in the rate of water loss, and the shorter the drying time required. By fitting six commonly used empirical models for thin-layer drying, among which the Wang model R2 was between 0.98878~0.99902, \begin{document}$ X $\end{document}2 and SSE were less than 0.0017 and 0.00849, which were the smallest values among the six models. And after verification, the predicted values of the model were basically fitted with the experimental values, which could better predict the moisture of Lycium barbarum extract during microwave vacuum drying change rule.

Breast cancer is the most common cancer in women worldwide with rising prevalence. The human epidermal growth factor receptor 2 (HER2) is crucial to the biological behavior and pathogenic mechanism of breast cancer. Approximately 45%-55% of all subtypes of breast cancer have low expression of HER2, which are classified as HER2 immunohistochemistry staining 1+ or 2+ and in situ hybridization (ISH) negative. Although in most cases, HER2 low expression (HER2-low) breast cancer is still classified as HER2 negative or triple negative in clinical practice, HER2-low differs from HER2 not detected (HER2-0) breast cancer not only in HER2 expression levels, there are also differences in terms of estrogen receptor (ER) status, primary tumor volume, lymph node involvement, and pathologic complete response (pCR) following neoadjuvant therapy and disease-free survival (DFS). In clinical trials targeting early-stage HER2-low breast cancer, the NSABP B-31 and N9831 trials demonstrated the possibilities for breast cancer patients to benefit from adjuvant trastuzumab therapy; however, in phase Ⅲ prospective randomized controlled study NSABP B-47, trastuzumab did not alter invasive disease-free survival (iDFS), 5-year interval without distant recurrence, or overall survival (OS) in patients with HER2-low breast cancer. Recent years have seen the emergence of clinical trials for targeted treatments for advanced HER2-low breast cancer, focusing mostly on trastuzumab, lapatinib, and antibody-drug conjugate (ADC), such as trastuzumab emtansine (T-DM1), DS-8201 (also known as trastuzumab deruxtecan, T-DXd, Enhertu), and SYD985. Phase Ⅲ trial CALGB9840 demonstrated a lack of therapeutic effect of trastuzumab and a narrow therapeutic window that could not be overcome by changing the dose of lumretuzumab in HER2 non-over-expressed breast cancer, respectively. Two randomized phase Ⅲ trials (EGF30001 and EGF100151) both found that receiving lapatinib did not improve progression-free survival (PFS) in patients with HER2-low breast cancer. T-DM1 sensitivity was initially observed in patients with HER2-low breast cancer in the single-arm phase Ⅱ studies 4258g and 4374g, but results were still uncertain because of the small number of patients. The phase Ⅲ clinical study DESTINY-Breast04 proved the safety and efficacy of DS-8201 (5.4 mg/kg) in HER2-low metastatic breast cancer. The phase Ⅰ clinical trial proved the efficacy and safety of 1.2 mg/kg SYD985 intravenously in HER2-low breast cancer. Additionally, there are currently ongoing clinical trials for several novel anti-HER2 therapeutics, including novel ADC drugs (RC48-ADC, ARX788, A166, etc.), bispecific antibodies (KN026, ZW25, ertumaxomab, etc.), and breast cancer vaccines (nelipepimut-S, GP2, AE37, etc.). In this paper, we will review the major clinical trials of targeted therapies for HER2-low breast cancer.

Plasmonic skyrmions are a subject of significant interest due to their potential applications in optics, photonics, and electromagnetic wave technology. These skyrmions are created by the interference of surface plasmon polaritons or spoof localized surface plasmons (SLSP), offering new possibilities for controlling light–matter interactions and structuring light. In this study, we have demonstrated the generation of both electric and magnetic skyrmions simultaneously using a rotational symmetric SLSP spiral meta-structure lattice, operating across a broad range from microwave to terahertz frequencies. By implementing them into a resonance configuration of the quasi-bound state in the continuum through symmetry breaking, we enhance the Q factor and fields, resulting in highly sensitive sensing performance. The SLSP metasurface enables tunable plasmonic skyrmions controlled by the incident polarization. Our findings have potential applications in highly sensitive sensing, filtering, modulation, and communication.

Water is the main component of wheat flour dough. Its content, distribution, presence state, and state of existence moisture have an important impact on the processing characteristics, preservation and product quality stability of the flour dough. Wheat flour is composed of a variety of components such as protein, starch, fat, pentosan, minerals and etc. Wheat flour is mixed with water to form a dough, in which complex physicochemical changes occur. The composition and physico-chemical properties of the various components in the dough have an important influence. Therefore, understanding the changes of different components in the process of dough mixing with water is of great significance for the quality control and quality improvement of products. In this review, the research results in related fields in recent years were classified and summarized, the interaction mechanism between different components in wheat flour and with water molecules was systematically analyzed, the water absorption and water holding characteristics of different components of wheat flour were discussed, and the effects of different components of wheat flour on water distribution and migration were analyzed. This paper concluded the key ingredients that determine the moisture migration and product quality of dough, such as protein, starch, damaged starch and pentosan etc., in order to further guide the production of wheat flour products.

Objiective: In presence of measurement uncertainty evaluation, the detection methods, with water-sodium chloride pretreatment, for health food was evaluated. Methods: A mathematical model was established to analysis of uncertainty sources. Then the individual components of uncertainty were evaluated. Finally, the combined uncertainty and extended uncertainty were calculated. Results: The uncertainty caused by several factors, including the fitting of the standard curve, the preparation of solution and standard, the repeatability of measurement, and the weigh of sample.The contents of mevastatin, lovastatin and simvastatin were 0.099 2, 0.101 0, 0.099 5 mg/kg in health foods, respectively. The relative combined standard uncertainties were about 0.003 2, 0.005 6, 0.005 1 mg/kg, k=2. Conclusion: Water-sodium chloride pretreatmen can reduce the interference of matrix and the uncertainty introduced by repeatability.

Objective In this study, we aimed to identify long non-coding RNAs (lncRNAs) that play important roles in starvation stress, analyze their functions, and discover potential molecular targets to alleviate starvation stress to provide a theoretical reference for subsequent in-depth research. Methods We generated a piglet starvation stress animal model. Nine Yorkshire weaned piglets were randomly divided into a long-term starvation stress group (starved for 72 h), short-term starvation stress group (starved for 48 h), and the control group. LncRNA libraries were constructed using high-throughput sequencing of piglet ileums. Results We obtained 11,792 lncRNAs, among which, 2,500 lncRNAs were novel. In total, 509 differentially expressed (DE)lncRNAs were identified in this study. Target genes of DElncRNAs were predicted via cis and trans interactions, and functional and pathway analyses were performed. Gene ontology functions and Kyoto encyclopedia of genes and genomes analysis revealed that lncRNA-targeted genes mainly participated in metabolic pathways, cellular processes, immune system processes, digestive systems, and transport activities. To reveal the mechanism underlying starvation stress, the interaction network between lncRNAs and their targets was constructed based on 26 DElncRNAs and 72 DEmRNAs. We performed an interaction network analysis of 121 DElncRNA–DEmRNA pairs with a Pearson correlation coefficient greater than 0.99. Conclusion We found that MSTRG.19894.13, MSTRG.16726.3, and MSTRG.12176.1 might play important roles in starvation stress. This study not only generated a library of enriched lncRNAs in piglets, but its outcomes also provide a strong foundation to screen key lncRNAs involved in starvation stress and a reference for subsequent in-depth research.

PurposeThe incidence of seroma and postoperative pain after Gilbert type III inguinal hernia repair is high. To reduce postoperative complications, this study investigated the clinical efficacy of laparoscopic closed hernia ring combined with a patch repair for Gilbert type III indirect inguinal hernia.MethodsThrough a prospective randomized controlled study, a total of 193 patients with Gilbert type III indirect inguinal hernia admitted to Nanchong Central Hospital affiliated with Chuanbei Medical College from May 2020 to December 2021 were selected and randomly divided into the inner ring closed group (85 patients) and the inner ring non-closed group (95 patients). The patients in both groups underwent laparoscopic tension-free repair of their inguinal hernias. General information such as operative time, postoperative hospital stay, and hospital cost were compared between the two groups, and the patients were followed up at 1, 7, 14, 21, and 28 days and then 3, 6, and 12 months after surgery to compare complications such as incidence of seroma, volume of the seroma fluid, incidence of pain, and visual analogue scale (VAS) pain score.ResultsThere was no conversion to open procedures in any of the patients. The operation time of the closed group was significantly longer than that of the non-closed group (64.2 ± 12.2 vs. 55.3 ± 9.5 min, P 0.05). The postoperative follow-up period was 3–20 months, and no chronic pain or recurrence occurred during the postoperative follow-up period in either group.ConclusionsClosure of the hernia ring is safe and effective for laparoscopic hernia repair for Gilbert type III inguinal hernia, and it significantly reduces the incidence of postoperative seroma and further reduces the postoperative pain without increasing the risk of postoperative infection and recurrence.

ObjectiveTo establish a method for determination of the content of chloramphenicol in milk powder by liquid chromatography-mass spectrometry, and apply it to test the uniformity and stability of reference material and determine the value.MethodsThe milk powder was reconstituted by adding water, extracted with ethyl acetate, degreased with n-hexane, extracted with ethyl acetate again, and finally quantified by the isotope internal standard method.ResultsChloramphenicol had a good linear relationship in the range of 0.4-4.0 ng/mL, the correlation coefficient was 0.999, the average recovery rate was 100.5%, the relative standard deviation was 1.1%-3.2% (n=6), and this method had a weak matrix effect in milk matrix.ConclusionThe method is accurate and reliable, and can be used for the determination of reference materials. After jointly determination by 11 laboratories, the characteristic value and the expanded uncertainty (k=2) of the reference material for the analysis of chloramphenicol residues in milk powder are (1.92±0.30) μg/kg and (5.65±0.53) μg/kg.

Pipe system conveying fluid faces the problem of multi-order resonance failure caused by broadband excitation. For solving above problem, the dynamic stiffness method is employed to solve the dynamic equations of multi-span pipes considering the temperature effect. Combining the obtained natural frequency and the rule of resonance failure of pipe system, a multi-order anti-resonance system reliability model is established in this paper. To analyze the effect of input variable uncertainty on the probability of system resonance failure, the variance-based importance measurement index is further established. By introducing the active learning Kriging (ALK) model, the resonance failure probability and importance measurement index can be calculated efficiently. The effects of fluid flow velocity, pressure and temperature on the probability of pipe resonance failure are analyzed in detail, which has significant guidance for the anti-resonance optimization design of pipes.

Formaldehyde (FA) is a commercially important chemical applied in industry and scientific research. However, FA has a distinct impact on learning and memory. Although the mechanisms of FA toxicity have been well studied, additional research is required to establish the mechanisms of neuroprotection in cases of FA exposure. Docosahexaenoic acid (DHA) is a polyunsaturated fatty acid with a variety of health benefits, including the enhancement of learning and memory. In this study, we investigated the neuroprotective effects of DHA in Drosophila melanogaster that had ingested FA. Our data suggested that DHA enhanced reproductive processes, leading to an increase in the number of eggs, larvae, and adults. Surprisingly, we found that DHA had a mild protective effect against FA-induced impairments in learning and memory.

The increase of sulfide (S2−) during the water flooding process has been regarded as an essential and potential risk for oilfield development and safety. Kriging and stochastic simulations are common methods for assessing the element distribution. However, these traditional simulation methods are not able to predict the continuous changes of underground S2− distribution in the time domain by limited known information directly. This study is a kind of attempt to combine stochastic simulation and the modified probabilistic neural network (modified PNN) for simulating short-term changes of S2− concentration. The proposed modified PNN constructs the connection between multiple indirect datasets and S2− concentration at sampling points. These connections, which are treated as indirect data in the stochastic simulation processes, is able to provide extra supports for changing the probability density function (PDF) and enhancing the stability of the simulation. In addition, the simulation process can be controlled by multiple constraints due to which the simulating target has been changed into the increment distribution of S2−. The actual data test provides S2− distributions in an oil field with good continuity and accuracy, which demonstrate the outstanding capability of this novel method.

The study aimed to analyze and compare dosimetric differences with various thicknesses and frequencies of bolus in post-mastectomy intensity-modulated radiotherapy. Based on the Oncentra4.1 treatment planning system, Thirty-eight post-mastectomy patients were selected randomly between 2017 and 2021. Three sets of simulated treatment planning with 5_mm all, 5_mm half, and 10_mm half virtual boluses were formed. A total prescribed dose of 50 Gy regimen was delivered in 25 fractions over 5 weeks, in which half-time bolus was used for 15 out of 25 fractions. The dosimetric parameters of target areas, skin, and organs at risk were compared. Furthermore, normal tissue complication probability (NTCP) was evaluated for the skin. Regarding the D2, D50, V90, V95, and V115 of the clinical target volume, the 5_mm all bolus group was prominently better than other groups, and the D50 and V90 of the clinical target volumes were statistically significant (p < 0.05). Regarding the D2, D50, D95, D98, Dmax, V90, V95, V115, homogeneity index (HI), and conformity index of the planning target volume, the 5_mm thick bolus group was prominently better than other groups, and the D50, D95, D98, V90, V95, and HI of the clinical target volumes were statistically significant (p < 0.05). For organs at risk, there was no statistical significance for the three planning groups, but the 5_mm all bolus group was prominently better than other groups in the V45 of the esophagus, V30, V40, and Dmax of the heart, V50, Dmax, and Dmean of the humerus head, V20, V30, and Dmax of the left lung, Dmax and Dmean of the thyroid, and Dmean of the trachea. Calculated with the 5_mm all bolus, the mean dose, V40, V45, and V50 for the skin structure, were all higher than other bolus regimens, while the dose maxima (Skinmax and V55) were all lower than others. Regarding the skin radiobiological evaluation, the NTCP of the 5_mm all bolus group was prominently better than other groups and was statistically significant (p < 0.05). Besides, the monitor unit of 5_mm all bolus regimen was the minimum compared with other groups and was statistically significant (p < 0.05). Therefore, the 5_mm all bolus group can not only improve the dose but also reduce the hot dose of skin and target volume, as well as reduce the NTCP. Our study provides a clinical reference in the delivery of post-mastectomy radiotherapy.

Changing landscape patterns would alter ecosystem components and functions, affecting the supply of ecosystem services. Understanding the spatial and temporal variations of ecosystem services is an important basis for ecosystem management and planning decisions and is of great significance for the realization of regional sustainable development. Based on Landsat TM/OLI remote sensing images from 1990, 2000, 2010, and 2020 in the Li River Basin, we explored the spatial and temporal variabilities of ecosystem services in the Li River Basin over the past 30 years, from both horizontal and vertical dimensions, using modified equivalence factor method and spatial autocorrelation analysis. The research findings are as follows: (1) Forestland has consistently been the dominant landscape type in the Li River Basin, with its area continuously increasing, while farmland, water bodies, and grassland have decreased, and construction land and bare land have increased. (2) The value of ecosystem services in the Li River Basin exhibited an initial increase followed by a decrease trend, with a net increase of 9.20 × 108 yuan. Forestland contributed the most to the value of ecosystem services. (3) Hydrological regulation and climate regulation are the dominant functions of the Li River Basin’s ecosystems, accounting for over 50% of the total contribution. (4) The value of ecosystem services per unit area increases with increasing slope and elevation. The segments with slopes ranging from 15 to 25 degrees and elevation zones between 200 and 500 m have the highest total value of ecosystem services. (5) The overall level of ecosystem services in the Li River Basin is relatively high and continues to rise, but areas with a low ecosystem service value are gradually concentrated. (6) The Moran’s I values for ecosystem services in all four periods are greater than 0, indicating a significant positive spatial autocorrelation. The overall pattern of ecosystem services is relatively stable, but there are significant spatial variations, which are characterized by lower values in the central area and higher values in the surrounding areas. The research findings provide a scientific basis for watershed ecological environment construction, optimal allocation of land resources, and sustainable landscape management.

We are concerned with the following Schrödinger–Newton problem:

A leaky-wave antenna (LWA) realizes radiation of travelling wave along guiding structures. Periodic modulation is an effective approach to turn non-radiating modes into radiating modes. A high-efficient LWA based on spoof surface plasmon polaritons (SSPPs) loaded with parasitic patch array is proposed. Sinusoidal modulation is used for the radiation of SSPPs, while parasitic array mitigates the open stopband (OSB) effect. A prototype is fabricated and measured. The measured and simulated results agree well with each other. Such design shows wide angle coverage of 83° from backward to forward and stable gain distribution of about 12 dB within the whole operating band.

This letter presents a novel unequal bandpass filtering power divider based on hybrid-mode of half mode substrate integrated waveguide (HMSIW) and spoof surface plasmon polaritons (SSPPs). Bandpass response is achieved by combining the transmission properties of HMSIW and SSPPs simultaneously. The operating bandwidth can be designed in a wide range by simply optimizing the dimensions of HMSIW and SSPPs. In addition, defected ground structures (DGSs) are etched on the bottom of the substrate to improve out-of-band suppression. The power division ratio of the proposed unequal power divider is finally optimized to 1:3. The measured results agree with the simulated one. Such design provides a stable power division within wide frequency range from 6.5 to 9.5 GHz.

Abstract In this paper, we present to achieve a broadband miniaturized transmission waveguide based on complementary spoof surface plasmon polaritons (CSSPPs). For this purpose, a novel SSPP design that consists of a corrugated slot line and a group of additional interdigital structures (ISs) is proposed, which brings in an extra solution to control the cut-off property of CSSPPs. The transmission cut-off frequency of the proposed design decreases with the increasing of the number of the ISs. Since the width of CSSPP waveguide is directly related to the operating frequency, the degree of miniaturization can be modulated freely by carefully choosing the number of the ISs. A prototype of device with four-ISs introduced is designed and fabricated. And the cut-off frequency of the design decreases from 10 GHz to 5.3 GHz, when the ISs are added. Experimental results agree well with the numerical simulations. The proposed design illustrates great potentials in modern plasmonic integrated circuits.

The rotational speed of the toothed rolls crusher is a key parameter for controlling the particle size of the crushed product.At present, the determination of the rotational speed is in a qualitative stage.There is no corresponding theory to guide.Based on the Grady-Kipp dynamic fracture model, the relationship between loading speed and product particle size is analyzed.The anthracite and gangue crushed at different loading speeds was carried out by drop hammer test machine.The results show that the average size of the two materials decreases with the increase of loading speed with power law.The test results verify the correctness of the fracture model, and provide a reference for the determination of the loading speed of toothed rolls crusher.

Abstract Background Fatigue is an important clinical finding in patients with chronic hepatitis virus infection. However, studies assessing fatigue in patients with chronic hepatitis B (CHB) are very limited. This study aimed to quantify the severity of fatigue in patients with CHB, to determine whether perceived fatigue reflects impairment of functional ability, and to explore potential causes. Methods A total of 133 patients with histologically proven CHB and 59 community controls were assessed using the fatigue impact scale (FIS). Results The degree of fatigue was significantly higher in patients with CHB than in controls (mean (range) FIS 24.9 (0–91) vs. 15.7 (0–31), p

The SWI/SNF complex is an important multi-subunit protein complex that regulates gene expression in eukaryotic cells. It is widely involved in various biological processes such as signal transduction, cell cycle and cell differentiation. SWI/SNF complex subunit mutations occur in more than 20% of malignant tumors. This article reviews the role and characteristics of this complex and its subunits in malignant tumors, and explores the potential clinical application of SWI/SNF complexes in tumor therapy.

Purpose. Based on the econometric model (Kuznets curve) of the relationship between economic growth and environmental pollution – Environmental Kuznets Curve, this article analyses the relationship between economic growth and environmental pollution in Henan Province, and studies the natural economic relationship. Methodology / approach. Three kinds of regional pollution index data of waste gas pollution and solid waste pollution and relative data of per capita GDP in Henan province were analyzed by using STATA software and OLS method was used to fit the relationship between environmental quality and economic growth, and the regression curve with the best fitting degree was obtained. Results. This article analyses the relationship between the overall environmental quality and economic growth in Henan Province over the years. According to the established data model it is obviously that economic growth itself cannot promote the improvement of environmental quality. To realize the double goals of economic growth and environmental protection, the key is to find out the inherent law of economic change in the process of economic growth, so as to construct a long-term mechanism of promoting environmental friendly economic growth. It is necessary: strengthening of pollution control and reduce pollutant discharge; follow the economic road of recycling resources; optimizing industrial structure and promoting coordinated sustainable development; adhere to the policy of energy saving and emission reduction. Originality / scientific novelty. Author’s developed econometric model is very useful in empirical assessment for the sustainable development of resources, environment and economy in Henan Province, and to provide a decision-making reference for the development of ecological environment in Henan Province. Accordingly, the proposed method, in the face of high-speed economic development today, put forward the countermeasures of economic sustainable development. Practical value / implications. Using the author’s proposed method leads to the achievement of the following results: can better promote Henan Province economy and ecological environment coordinated development.

This study develops a differential‐fed filtering patch antenna, which features superior frequency selectivity, compact size, low cross‐polarisation, and symmetrical radiation patterns. The proposed antenna consists of a rectangular patch on the top layer, which is differentially fed by a balun bandpass filter on the bottom layer. A pair of rectangular coupling slots were etched on the middle layer for energy coupling. The patch antenna performs not only as the radiator but also as the last resonator of the whole filter circuit for compactness. A prototype of the proposed filtering antenna operating at 2.45 GHz was fabricated and tested. The measured in‐band peak gain is 5.9 dBi with steep roll‐off at band edges, and the out‐of‐band gain is less than − 25 dBi. Moreover, symmetrical radiation patterns and low cross‐polarisation levels of − 22 dB are also realised for the proposed filtering antenna.

This paper presents a 3D band-absorptive frequency selective rasorber (FSR). Such an FSR is absorptive within a specific band and almost transparent below the absorption band. The definition and evaluation of the band-absorptive FSR is initially provided and followed by the design concept of 3D FSR. An example is then proposed, whose unit cell is composed of 3D absorber and 3D band-stop FSS. An equivalent circuit model is established for understanding its operating principle. A prototype of the proposed 3D band-absorptive FSR is fabricated. The measured results show that it has an absorption band ( $\vert S_{11}\vert \le -10$ dB and $\vert S_{21}\vert \le -10$ dB) from 4.21 to 6.51 GHz, with a thickness of 0.17 wavelength at 4.21 GHz. Moreover, $\vert S_{21}\vert $ is higher than −1 dB at the frequencies below 1.28 GHz. The proposed band-absorptive FSR can be used as radomes for low-frequency antennas in military communications or spectrum monitoring systems.

In this paper, the integration design of a millimeter-wave filtering patch antenna array fed by a substrate integrated waveguide (SIW) four-way anti-phase filtering power divider is proposed. The multilayer four-way anti-phase filtering power divider handily implemented using the intrinsic field distribution of TE20-mode in SIW is proposed for miniaturization. The signal of the lower substrate integrated waveguide cavity (SIWC) bandpass filter is directly coupled to the upper TE20-mode SIW through a coupling slot. The intrinsic field distribution of TE20-mode SIW is used to generate anti-phase signals. This filtering power divider can be utilized as the feeding structure of a millimeter-wave filtering antenna array. To verify the design concept, a 28-GHz SIW-fed 1 × 4 filtering patch antenna array with three-layer substrates is designed and fabricated. The measured results show a fractional bandwidth of 5.03% ranging from 27.15 to 28.55 GHz, a peak gain of 11.1 dBi, cross-polarization levels lower than -20 dB, symmetric radiation patterns in both E-plane and H-plane, and high selectivity.

A compact dual-polarized antenna element covering the frequency bands of 0.773~1.0405 GHz and 1.69~2.83 GHz is proposed in this paper. The nested scheme is adopted and the performances of the lower- and upper-band element are analyzed, respectively. A ground platform in the center of lower-band element lowers the resonance frequency of element, makes the structure compact, and suppress the mutual interference between the lower- and upper-band elements. The simulated and measured results show that the proposed structure has stable smooth radiation patterns and the peak gains of 8.83 and 9.34 dBi for the lower- and upper-band elements, respectively. Based on the proposed elements, an array composed of three lower-band elements and five upper-band elements is designed and measured. The results show that the array achieves a stable flat half-power beamwidth (HPBW), isolation better than 25 dB and cross polarization levels less than -15 dB are obtained. The proposed antenna is a candidate for the multi mobile communication systems.

In this paper, a new wideband DOA estimation method for arbitrary array application is proposed. The arbitrary array manifold is approximately decomposed under the concept of manifold separation technique (MST) and a linear combination of the equal interval sampling complex exponentials (EISCE) can be synthesized. Since the EISCEs at all frequencies contain the same DOA information, they can be annihilated by the same spatial annihilating filter. So, the coherent annihilating scheme is proposed, and all narrowband components are coherently combined to construct an optimization problem under the structural total least squares framework. During the optimization problem construction, the general solution method is proposed to enable the model approximation error in MST to be reduced to a negligible level. Finally, the optimization problem is solved through the multiple measurement vectors structural total least norm (MMV-STLN) approach and the DOAs are estimated from the reconstructed spatial annihilating filter. The new method is free of frequency focusing and is capable of handling both incoherent and coherent signals. The simulation results verify that the proposed method surpasses the existing methods largely in resolution and estimation performance under the low SNR, snapshot deficient, and closely spaced sources scenarios.