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At present，the most widely used control algorithms in the field of active noise control（ANC）are the classical FxLMS algorithm and its improved algorithms，which are applied to noise control in large spaces and areas such as the turboprop aircraft cabin，the amount of algorithmic calculations will be rapidly expanded with the increase in the number of channels of the ANC system，and the real-time requirements of algorithms are difficult to meet. Sequential Partial Update FxLMS（SPU-FxLMS）algorithm effectively solves this problem，but its convergence performance is weaker than that of the FxLMS algorithm. In this paper，the improvements to the SPU-FxLMS algorithm for the problem of slow convergence are made，so that the algorithm can be converged with a faster speed in the early stage of the operation，and then converge with a lower speed after converging to a smooth state. After converging to a steady state，the algorithm continues to run with a low computational capacity. The theoretical derivation and simulation analysis of the improved algorithm are carried out. The results show that the algorithm has good noise reduction performance and robustness while further reducing the amount of computation，and has a good prospect for engineering applications.

Unmanned aerial vehicles (UAVs) are cutting-edge technologies used for military purposes world-wide at tactical, operational, and strategic levels. This study provides an overview of the history and current state of military drones, considering a global and Ecuadorian background. Then, a classification of the UAVs developed and built in Ecuador is conducted based on their endurance, altitude, and wing span to understand the national context and progress. The research also delves into the applications of UAVs in several military operations and missions, aiming to create a framework that aligns UAV capabilities with specific operational needs; this permits the identification of the challenges and opportunities the country faces. Unmanned aerial systems have changed the battlefield, and the government needs to adapt to a national strategy that incorporates this technology; this research analyzes and provides insights to improve military capabilities such as exploring modern UAV military applications, technical updates in communication, navigation, and data acquisition systems; and the integration of emerging technologies like smart materials, artificial intelligence, and electric propulsion systems. This study provides valuable insights into the Ecuadorian UAVs that enhance the country’s military operations and offer some applications and uses of this technology for national security.

In liquidliquid extraction systems, extractants and extracted complexes may have surface activity, resulting in the formation of a variety of supramolecular assemblies such as vesicles and micelles. The assemblies are limited at microscopic and mesoscopic scales. Researches on interface of extraction also focus on microscopic and mesoscopic scales at present. Recently, our group first reported macroscopic supramolecular assembly(MSA) at the interface of extraction systems. The interface can be studied on macroscopic scales by MSA. The process of MSA in ionic liquids(ILs) based extraction systems also provides a new way to study complex supramolecular interactions between ILs and mediums. This review focused on microscopic, mesoscopic and macroscopic supramolecular assembly in extraction systems. First, the interface properties and the process of ion exchange in extraction were summarized. Next, the structures of mesoscopic supramolecular assemblies were reviewed . Finally, the macroscopic supramolecular assembly(MSA) at the interface of extraction systems and its application on separation were emphatically introduced. The MSA process at the interface enriches the extraction methods. And the Marangoni effect presented at the interface supplies a new approach to provide continuous driving force, which is an important scientific problem in the field of MSA.

The separation of strontium is important in the recovery of radioactive resources. Ionic liquids(ILs) based extraction systems of Sr have been greatly expanded, but the separation of Sr and Cs remains a problem. In addition, the problem of radioactive waste affects the application of IL systems in the field of spent fuel reprocessing. In this work, the macroscopic supramolecular assembly(MSA) of strontium at the interface of IL extraction systems and its basic research on the extraction of Sr were reported. The MSA behavior of Sr2+ in ionic liquid based extraction systems was studied and the structure of Sr-MSA was analyzed by mass spectrometry, 13C NMR, infrared spectroscopy and theoretical calculation. Sr-MSA was formed by using CnOHmimNTf2 (n=2, 3) as the ILs and CMPO, TODGA as the extractants. The three step mechanism of MSA process is proposed: complexes formed by Sr2+ and CMPO are extracted to IL phase. The complexes and IL assemble into nanoparticles driven by non covalent interactions such as electrostatic attraction, hydrogen, hydrophobic interaction. The nanoparticles aggregate into mesoscopic assemblies. The mesoscopic assemblies move to the interface and grow further into macroscopic intermediates. The intermediates finally generate into Sr-MSA under the traction from Marangoni effect. A new method for the selective extraction and one step solidification of Sr2+ from aqueous solutions was developed. The Sr-MSA can be taken out with tweezers easily from aqueous solution. The method can still be used in high acidity environment.

Photomutiplication-type organic photodetectors (PM-OPDs) are attractive for various next-generation technologies due to their lower cost, higher sensitivity and technological utility. Here, the authors report vacuum-processed narrowband PM-OPDs with enhanced sub-bandgap external quantum efficiency.

Abstract Highly responsive organic photodetectors allow a plethora of applications in fields like imaging, health, security monitoring, etc. Photomultiplication‐type organic photodetectors (PM‐OPDs) are a desirable option due to their internal amplification mechanism. However, for such devices, significant gain and low dark currents are often mutually excluded since large operation voltages often induce high shot noise. Here, a fully vacuum‐processed PM‐OPD is demonstrated using trap‐assisted electron injection in BDP‐OMe:C60 material system. By applying only −1 V, compared with the self‐powered working condition, the responsivity is increased by one order of magnitude, resulting in an outstanding specific detectivity of ≈1013 Jones. Remarkably, the superior detectivity in the near‐infrared region is stable and almost voltage‐independent up to −10 V. Compared with two photovoltaic‐type photodetectors, these PM‐OPDs exhibit the great potential to be easily integrated with state‐of‐the‐art readout electronics in terms of their high responsivity, fast response speed, and bias‐independent specific detectivity. The employed vacuum fabrication process and the easy‐to‐adapt PM‐OPD concept enable seamless upscaling of production, paving the way to a commercially relevant photodetector technology.

The development of vertical organic transistors with controllable threshold voltage is highly desirable for integrated circuit-based displays and sensors. Here, the authors report vertical organic permeable dual-based transistors with independently tunable on-currents and threshold voltages.

Objective The study was to investigate the effects of alanyl-glutamine (Ala-Gln) and glutamine (Gln) supplementation on the intestinal mucosa barrier in piglets. Methods A total of 180 barrows with initial weight 10.01±0.03 kg were randomly allocated to three treatments, and each treatment consisted of three pens and twenty pigs per pen. The piglets of three groups were fed with control diet [0.62% alanine (Ala)], Ala-Gln diet (0.5% Ala-Gln), Gln diet (0.34% Gln and 0.21% Ala), respectively. Results The results showed that in comparison with control diet, dietary Ala-Gln supplementation increased the height of villi in duodenum and jejunum (p

Continuous chemical extraction is considered to be one of the most common methods for the extraction of heavy metals speciations in plants. However, the basis for the extraction order of this method is not explained and has been rarely studied. In this paper, we analyzed the speciations of cadmium in plants by a four-step continuous extraction method. The extraction sequence of ethanol and water was studied to study the effect of extraction sequence on the extraction rate of extraction agent. The results showed that cadmium exists mostly in NaCl extraction state and the extraction rate of the two kinds of extraction agents decreased when the order of ethanol and water was changed.

A heavy-chain antibody (VHH) library against procymidone (PRM) was constructed via immunizing Bactrian camels. Through careful biopanning, seven nanobodies (Nbs) with different sequences were obtained. The variability in their performance was primarily attributed to the amino acid differences in complementarity-determining region 3 (CDR3), as analyzed by molecular docking. The Nb exhibiting the highest sensitivity, named NbFM5, was biotinylated and conjugated to streptavidin-labeled gold nanoparticles to preserve the epitope's activity and prevent a decrease in sensitivity due to traditional random electrostatic adsorption. Subsequently, a simple and sensitive immunochromatographic assay (ICA) was developed for rapid detection of PRM based on biotinylated Nb (btNb). The developed btNb-ICA showed a cut-off value of 200 ng/mL for visual judgment and a half-inhibitory concentration (IC50) of 6.04 ng/mL for quantitative detection. The limit of detection (LOD) was as low as 0.88 ng/mL. The recoveries in actual samples of crops ranged from 82.2 to 117.3%, aligning well with the results obtained from GC-MS/MS (R2 = 0.995). In summary, the developed btNb-ICA demonstrated high specificity and good accuracy for the rapid detection of PRM residues in vegetables. The total analysis time from preparing the sample to obtaining the result was less than 25 min.

Nanobodies (Nbs) have great potential in immunoassays due to their exceptional physicochemical properties. With the immortal nature of Nbs and the ability to manipulate their structures using protein engineering, it will become increasingly valuable to understand what structural features of Nbs drive high stability, affinity, and selectivity. Here, we employed an anti-quinalphos Nb as a model to illustrate the structural basis of Nbs' distinctive physicochemical properties and the recognition mechanism. The results indicated that the Nb-11A-ligand complexes exhibit a "tunnel" binding mode formed by CDR1, CDR2, and FR3. The orientation and hydrophobicity of small ligands are the primary determinants of their diverse affinities to Nb-11A. In addition, the primary factors contributing to Nb-11A's limited stability at high temperatures and in organic solvents are the rearrangement of the hydrogen bonding network and the enlargement of the binding cavity. Importantly, Ala 97 and Ala 34 at the active cavity's bottom and Arg 29 and Leu 73 at its entrance play vital roles in hapten recognition, which were further confirmed by mutant Nb-F3. Thus, our findings contribute to a deeper understanding of the recognition and stability mechanisms of anti-hapten Nbs and shed new light on the rational design of novel haptens and directed evolution to produce high-performance antibodies.

Citrinin is a toxic product usually produced during the Monascus fermentation. The presence of citrinin in xuezhikang capsule has been a concern due to its ingredient which is derived from monascus-fermented rice. A rapid and sensitive RP-HPLC method with fluorescence detection at λex = 331 nm and λem = 500 nm for analysis of citrinin in Monascus-fermented products was developed to analyze citrinin in Monascus-fermented products. The chromatography was performed with mobile phase containing acidified water and acetonitrile. The calibration curve was linear (r = 0.9999) over a range of 0.0107- 0.537 μg/mL. The limit of detection (LOD) and the limit of quantitation (LOQ) were 0.187 ng/mL and 0.6 ng/mL respectively. The analysis of xuezhikang capsules using the developed method suggested that the product does not contain detectable citrinin and the result has been further confirmed using independent LC-MS/MS analysis. The proposed method has also been applied to analyze 11 samples of other Monascus-fermented products. The results suggested that there were no detectable citrinin in 4 of the 11 samples, however citrinin with the levels between 0.10-594 ng/kg has been detected in the other 7 samples. It indicates that the proposed method can also be applied to carry out the quantitative detection of citrinin for other Monascus-fermented products.

The coverage quality measuring and optimization problems were studied using moving target tracking as the application background. Based on the idea of grid discretization, a graph-theory based algorithm was proposed to search minimal exposure path for the moving target barrier coverage problem using exposure as the performance metric. And a multi-step incremental barrier coverage optimization method was proposed based on the minimal exposure path. The proposed algorithms’ performance was validated by simulation experiments in the end. Experiments show the algorithms are applicable to the barrier coverage problems with arbitrary node distribution model,sensing model,network charac- teristics and moving path of the target, can decrease the number of nodes need to be deployed in order to meet the specific coverage quality requirement and accordingly cut the network cost significantly.

Dietary protein levels and cysteamine (CS) supplementation can affect growth performance and protein metabolism of pigs. However, the influence of dietary protein intake on the growth response of CS-treated pigs is unclear, and the mechanisms involved in protein metabolism remain unknown. Hence, we investigated the interactions between dietary protein levels and CS supplementation and the effects of dietary crude protein levels and CS supplementation on protein synthetic and degradative signaling in skeletal muscle of finishing pigs. One hundred twenty barrows (65.84 ± 0.61 kg) were allocated to a 2 × 2 factorial arrangement with five replicates of six pigs each. The primary variations were dietary crude protein (CP) levels (14% or 10%) and CS supplemental levels (0 or 700 mg/kg). The low-protein (LP) diets (10% CP) were supplemented with enough essential amino acids (EAA) to meet the NRC AA requirements of pigs and maintain the balanced supply of eight EAA including lysine, methionine, threonine, tryptophan, valine, phenylalanine, isoleucine, and leucine. After 41 days, 10 pigs per treatment were slaughtered. We found that LP diets supplemented with EAA resulted in decreased concentrations of plasma somatostatin (SS) (P

Hypoxia-inducible factor 1-α (HIF-1α) plays a critical role in angiogenesis-osteogenesis coupling during bone development and bone regeneration. Previous studies have shown that 17β-estradiol activates the HIF-1α signaling pathway and that mice with conditional activation of the HIF-1α signaling pathway in osteoblasts are protected from ovariectomy (OVX)-induced bone loss. In addition, it has been shown that hypoxia facilitates the osteogenic differentiation of mesenchymal stem cells (MSCs) and modulates Wnt/β-catenin signaling. Therefore, we hypothesized that activation of the HIF-1α signaling pathway by hypoxia-mimicking agents would prevent bone loss due to estrogen deficiency. In this study, we confirmed the effect of dimethyloxalylglycine (DMOG), a hypoxia-mimicking agent, on the HIF-1α signaling pathway and investigated the effect of DMOG on MSC osteogenic differentiation and the Wnt/β-catenin signaling pathway. We then investigated the effect of DMOG treatment on OVX-induced bone loss. Female C57BL/6J mice were divided into sham, OVX, OVX+L-DMOG (5 mg/kg/day), and OVX+H-DMOG (20 mg/kg/day) groups. At sacrifice, static and dynamic bone histomorphometry were performed with micro computed tomography (micro-CT) and undecalcified sections, respectively. Bone strength was assessed with the three-point bending test, and femur vessels were reconstructed and analyzed by micro-CT. Serum vascular endothelial growth factor (VEGF), osteocalcin, and C-terminal telopeptides of collagen type(CTX) were measured by ELISA. Tartrate-resistant acid phosphatase staining was used to assess osteoclast formation. Alterations in the HIF-1α and Wnt/β-catenin signaling pathways in the bone were detected by western blot. Our results showed that DMOG activated the HIF-1α signaling pathway, which further activated the Wnt/β-catenin signaling pathway and enhanced MSC osteogenic differentiation. The micro-CT results showed that DMOG treatment improved trabecular bone density and restored the bone microarchitecture and blood vessels in OVX mice. Bone strength was also partly restored in DMOG-treated OVX mice. Dynamic bone histomorphometric analysis of the femur metaphysic revealed that DMOG increased the mineralizing surface, mineral apposition rate, and bone formation rate. The serum levels of VEGF and osteocalcin were higher in DMOG-treated OVX mice. However, there were no significant differences in serum CTX or in the number of tartrate-resistant acid phosphatase-stained cells between DMOG-treated OVX mice and OVX mice. Western blot results showed that DMOG administration partly rescued the decrease in HIF-1α and β-catenin expression following ovariectomy. Collectively, these results indicate that DMOG prevents bone loss due to ovariectomy in C57BL/6J mice by enhancing angiogenesis and osteogenesis, which are associated with activated HIF-1α and Wnt/β-catenin signaling pathways.