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The design of waveforms plays a critical role in integrated sensing and communication (ISAC) systems. An ISAC waveform with a 0dB peak‐to‐average power ratio (PAPR) is designed by combining a Golay complementary sequence with a constant envelope orthogonal frequency‐division multiplexing. By adjusting the phase modulation parameters, this waveform allows for a trade‐offs between communication and sensing capabilities. The authors focus on several key performance metrics for the proposed ISAC waveform, notably using mutual information as a holistic performance indicator to assess both sensing and communication effectiveness. Through extensive numerical simulations, the authors demonstrate that the ISAC waveform significantly enhances detection probability compared to traditional phase‐modulated waveforms. The findings suggest that this approach is beneficial for designing low PAPR phase‐modulated ISAC waveforms, enhancing both the functionality and efficiency of ISAC systems. [ABSTRACT FROM AUTHOR]

Myocardial fibrosis is a critical concern in clinical medicine. This study explores the potential of odoratin as a treatment for myocardial fibrosis and investigates its underlying mechanisms. In vitro experiments involved stimulating primary mouse cardiomyocytes with TGF‐β1, followed by odoratin treatment, to assess levels of reactive oxygen species (ROS) and nitric oxide (NO). In vivo, a mouse model of myocardial fibrosis was established using abdominal aortic constriction (AAC) and treated with odoratin. ROS and NO levels in myocardial tissue were then evaluated. Immunofluorescence and Western blotting analysis showed that odoratin reduced excess ROS, enhanced NO production and decreased fibrosis‐related protein expression in vitro. In vivo, odoratin significantly improved cardiac function, reduced ROS, increased NO levels and mitigated fibrosis in AAC‐induced mice. Both in vitro and in vivo, odoratin inhibited the expression of NADPH oxidase 4 and EZH2, while promoting the expression of phosphorylated endothelial nitric oxide synthase (p‐eNOS) and PPARγ. The anti‐fibrotic effects of odoratin were reversed by PPARγ antagonism, and EZH2 overexpression diminished PPARγ activation by odoratin. These findings suggest that odoratin may combat myocardial fibrosis by balancing ROS and NO through PPARγ activation, with EZH2 inhibition likely playing a key regulatory role. [ABSTRACT FROM AUTHOR]

In tracking scenarios involving groups with dense targets, achieving effective data association is challenging due to mutual occlusion and interference among targets. The complexity of the tracking problem is further exacerbated in low‐observable environments by the increase in false alarm rates. The track‐before‐detect (TBD) is an advanced technology for detecting and tracking low‐observable targets, effectively mitigating data association problems by integrating multi‐frame echo data. However, the existing multi‐target TBD algorithms typically assume that the targets are spatially separated and are not suitable for scenarios involving group targets. A group target maximum‐likelihood probabilistic data association (GT‐ML‐PDA) algorithm, based on the concept of TBD, is proposed to track group targets effectively in low‐observable environments. The proposed algorithm divides group target tracking into two stages: group centre trajectory estimation and individual target trajectory estimation. To enhance the performance of the proposed algorithm, two strategies are suggested: modifying the equivalent measurements and extracting independent measurement sets for individual targets. Simulation results demonstrate that the proposed algorithm is capable of effectively tracking numerous individual targets within a group, even in the presence of heavy clutter. [ABSTRACT FROM AUTHOR]

A series of antimony-bridged viologen derivatives, stiboviologens, were obtained by introducing an antimony atom into the viologen skeleton. By modifying them through N-alkylation and N-arylation, the optoelectronic properties of the stiboviologens were finely tuned. The stiboviologens displayed strong redox properties, high conjugation, and low energy gaps. Notably, the presence of the antimony atom significantly enhanced the ultrafast metal to ligand charge transfer (MLCT) process (to approximately 1 ps), as determined by femtosecond transient absorption studies. Leveraging their excellent optoelectronic properties, the stiboviologens were successfully applied in electrochromism and utilized as both photosensitizers and electron transfer agents for catalyzing α-amino C(sp3)–H functionalization reactions including the oxidative cyclization reaction and cross dehydrogenative coupling reaction under visible light conditions. These findings highlight the potential of stiboviologens as promising materials in the field of optoelectronics and their versatile utilization in synthetic transformations. [ABSTRACT FROM AUTHOR]

The reactions of cyclic (alkyl)(amino)germylenes (CAAGe) with copper(I) and gold(I) complexes were investigated. CAAGe (1) reacts with CuBr(SMe2) leading to a tetrameric germylene complex [CAAGeCuBr]4 (2), whereas CAAGe (3) undergoes Au−Cl bond insertion with LAuCl (L=phosphine or N‐heterocyclic carbene) to afford germanium gold(I) complexes (5 and 6). Chlorine abstraction of 6 gives the cationic germylene gold(I) complex 7. [ABSTRACT FROM AUTHOR]

Both organic radicals and organoboron reagents have been broadly investigated, but the combination of them via direct C−H borylation as organic radical building blocks has never been achieved. Herein, a series of organoradical boron reagents, such as TTM‐Bpin and TTM‐BOH, were synthesized through the key step of C−H borylation of substrate TTM‐H ((2,6‐dichlorophenyl) bis(2,4,6‐trichlorophenyl)methyl) radical for the first time. They are air stable enough to be stored in the solid state for several months under dark conditions, and fully investigated through single crystal analysis, EPR and DFT calculations. Furthermore, they can smoothly work in the standard Suzuki–Miyaura coupling (SMC) reaction with retention of the carbon radical center. Meanwhile, these radical species bearing different boron units display fluorescent character and are potentially applied for the collective synthesis of luminescent organic radicals, as well as other functionalized open‐shell materials. [ABSTRACT FROM AUTHOR]

To obtain the accurate time difference of arrival (TDOA) and frequency difference of arrival (FDOA) for passive localization in an unmanned aerial vehicle (UAV) swarm, UAV swarm network synchronization is necessary. However, most of the traditional distributed time synchronization protocols are based on iteration, which hinders efficiency improvement. High communication costs and long convergence times are often required in large-scale UAV swarm networks. This paper presents a neighborhood selection-all selection (NS-AS) synchronization mechanism-based moving source localization method for UAV swarms. First, the NS-AS synchronization mechanism is introduced, to model the UAV swarm network synchronization process. Specifically, the UAV neighbors are first grouped by sector, and the most representative neighbors are selected from each sector for the state update calculation. When the UAV swarm network reaches a fully connected state, the synchronization mechanism is switched to select all neighbors, to improve the convergence speed. Then, the TDOA-FDOA joint localization algorithm is employed to locate the moving radiation source. Through simulation, the effectiveness of the proposed method is verified by the system convergence and localization performance under different parameters. Experimental results show that the synchronization mechanism based on NS-AS effectively improves the convergence speed of the system while ensuring the accuracy of moving radiation source localization. [ABSTRACT FROM AUTHOR]

Herein, pre-functionalized benzyne precursors 5, 6 and 10 bearing a phosphoryl group were efficiently synthesized through a phospho-Fries rearrangement reaction on gram scales. Based on the versatile benzyne reactions ranging from nucleophilic addition and [3+2] and [4+2] cycloadditions to insertion reactions, a series of arylated organophosphorus molecules were readily achieved under mild reaction conditions. Attributed to the electron-withdrawing ability and the steric hindrance environment of phosphoryl groups, the reaction proceeded with high regioselectivity at the C1 position of 3-phosphoryl benzynes via a nucleophilic attack. Thus, this report illustrated novel phosphorus-functionalized benzynes and their regioselective formation of various poly-substituted organophosphorus arenes. [ABSTRACT FROM AUTHOR]

The problem of passive localization using an unmanned aerial vehicle (UAV) swarm is studied. For multi-UAV localization systems with limited communication and observation range, the challenge is how to obtain accurate target state consistency estimates through local UAV communication. In this paper, an ant colony pheromone mechanism-based passive localization method using a UAV swarm is proposed. Different from traditional distributed fusion localization algorithms, the proposed method makes use of local interactions among individuals to process the observation data with UAVs, which greatly reduces the cost of the system. First, the UAVs that have detected the radiation source target estimate the rough target position based on the pseudo-linear estimation (PLE). Then, the ant colony pheromone mechanism is introduced to further improve localization accuracy. The ant colony pheromone mechanism consists of two stages: pheromone injection and pheromone transmission. In the pheromone injection mechanism, each UAV uses the maximum likelihood (ML) algorithm with the current observed target bearing information to correct the initial target position estimate. Then, the UAV swarm weights and fuses the target position information between individuals based on the pheromone transmission mechanism. Numerical results demonstrate that the accuracy of the proposed method is better than that of traditional localization algorithms and close to the Cramer–Rao lower bound (CRLB) for small measurement noise. [ABSTRACT FROM AUTHOR]

Multifunctional solar energy conversion offers a feasible strategy to solve energy, environmental and water crises. Herein, a series of platinum(II)‐tethered chalcogenoviologens (PtL+‐EV2+, E=S, Se, Te) is reported, which integrate the functions of photosensitizer, electron mediator and catalyst. PtL+‐EV2+ (particularly for PtL+‐SeV2+)‐based one‐component solar H2 production could be triggered not only by EDTA, but also by facultative anaerobic and aerobic bacteria relying on a simplified mechanism, along with efficient antibacterial activities. In addition, by using real pool water, PtL+‐SeV2+ achieved multiple functions, including H2 production, antibacterial action and acid removal, which supplied a new strategy to solve various problems in real life via a single system. [ABSTRACT FROM AUTHOR]

A series of pyrene or pyrene‐o‐carborane‐appendant selenoviologens (Py‐SeV2+, Py‐Cb‐SeV2+) for enhanced photocatalytic hydrogen evolution reaction (HER) and reduction of alkynes is reported. The efficient photoinduced electron transfer (PET) from electron‐rich pyrene‐o‐carborane heterojunction (Py‐Cb) with intramolecular charge transfer (ICT) characteristic to electron‐deficient selenoviologen (SeV2+) (kET = 1.2 × 1010 s−1) endows the accelerating the generation of selenoviologen radical cation (SeV+•) compared with Py‐SeV2+ and other derivatives. The electrochromic/electrofluorochromic devices' (ECD and EFCD) measurements and supramolecular assembly/disassembly processes of SeV2+ and cucurbit[8]uril (CB[8]) results show that the PET process can be finely tuned by electrochemical and host–guest chemistry methods. By combination with Pt‐NPs catalyst, the Py‐Cb‐SeV2+‐based system shows high‐efficiency visible‐light‐driven HER and highly selective phenylacetylene reduction due to the efficient PET process. [ABSTRACT FROM AUTHOR]

Accurate georegistration is required in airborne surveillance of ground targets since even a small bias in sensor registration may result in a large error in the converted target geolocation. Thus, this article addresses the problem of estimating and correcting the sensor biases in target geolocation. The effect of sensor biases on target geolocation is modeled and decoupled from the true target geolocation. By assuming that the biases are small, the effect of biases is separately addressed by a linear term in the converted target geolocation. Based on this model, two computationally efficient methods are proposed to estimate the biases. The converted target geolocation can then be corrected based on the bias estimates. Simulation results demonstrate the effectiveness of the proposed methods in estimating sensor biases and correcting target geolocations as well as their high computational efficiency. [ABSTRACT FROM AUTHOR]

The selective late-stage functionalization of BN-containing polycyclic aromatic hydrocarbons (BN-PAHs) is very challenging. Herein, dithienoazaborines (BNDT, 3a and 3b) were synthesized as model compounds, and two kinds of selective functionalized BNDT precursors, 4a and 4b were synthesized due to the strong polar effect of the BN bond, leading to a series of BNDT derivatives for the following coupling reactions. Based on this, two kinds of BNDT-based small molecules and oligomers with BN bonds on the conjugated main chain and side chain were synthesized accordingly. The BNDT derivatives (5b/6b/7b) with a BN bond on the conjugated side chain showed lower LUMO energy levels and narrower band gaps than those with a BN bond on the conjugated main chain (5a/6a/7a). Different modifications and polymerization have effects on the photophysical properties and all derivatives are highly selective to fluoride ions. This work realized a new strategy for selective late-stage functionalization of BN-PAHs with selective π-conjugated extension, laying a solid foundation for the subsequent BN chemistry and application of functionalized BN-PAHs. [ABSTRACT FROM AUTHOR]

A series of ultralong organic phosphorescence (UOP) materials (XCz-Cm/Lab, X = B, C, N, and S) with tunable UOP colors and lifetimes through the combination of commercial/lab-synthesized carbazole (Cz-Cm/Lab) with the Lewis acidic or Lewis basic main-group elements is reported. With the increasing Lewis basicity from boron to carbon, nitrogen and sulfur in scaffolds, the corresponding lowest triplet excited state energy levels of the XCz gradually decreased, and the UOP colors of XCz-Cm showed a bathochromic shift from yellow-green (∼534 nm) to orange-red (∼580 nm). Conversely, the distances of π–π interaction of the XCz molecules and the radiative decay from the lowest triplet excited state to the ground state gradually increased, endowing the XCz-Cm with tunable UOP lifetimes (0.068–0.555 s). The XCz-Lab exhibited similar photoluminescence behavior as XCz-Cm, and the difference between XCz-Cm and XCz-Lab was attributed to the isomer of Cz-Cm. Owing to the long-lived triplet excited states, the CCz-Cm nanoparticles were applied in real-time lymph node afterglow imaging through intravenous injection in vivo successfully. This contribution not only presents a new versatile strategy for modulating UOP properties by introducing Lewis acidic/basic main-group elements but also extends their applications in afterglow imaging. [ABSTRACT FROM AUTHOR]

A series of novel π-extended chalcogenoviologens with stable radical states, narrow band gaps and low reduction potentials were synthesized. These compounds can be used as photosensitizers and electron mediators for excellent visible-light-driven photochromism and hydrogen evolution due to their strong absorption in the visible region and fast electron transfer properties. Particularly, Se-PhV2+ (3b) showed the highest value reported to date for viologen-based visible-light-driven hydrogen evolution. The more stable radical-forming chalcogenoviologens (5 times more than methyl viologen) can be used as an active layer in the static/dynamic electrochromic displays with excellent performances. The wifi-controlled flexible ECD, electrochromic writing board, pixel e-billboard/reader and dynamic color display with a four-latticed pixel matrix were exploited to testify the better performance, including low operation voltage, high efficiency and energy-saving ability. In addition, a double-encrypted electrochromic display was developed for the first time, which could demonstrate "XJTU" and the school badge alternatively, controlled by the application of different voltages. This discovery not only provided potential implications for novel smart windows, but also laid the foundation for simplified energy-efficient colorful displays and future wearable devices. [ABSTRACT FROM AUTHOR]

Boragermene 3 featuring a double bond between the Ge and dicoordinate B atoms has been synthesized for the first time by reacting the cyclic (alkyl)(boryl)germylene–PMe3 adduct 1 with Cl2BN(SiMe3)2 followed by reductive dehalogenation with KC8. Addition of a Lewis base (MeNHC) to 3 leads to the formation of the corresponding adduct 4, which shows double bond character between the Ge and tricoordinate B atoms. Compound 3 undergoes hydrogenation with H2 concomitant with a complete scission of the Ge=B bond. [ABSTRACT FROM AUTHOR]

A cyclic (alkyl)(amino)germylene undergoes a ring expansion reaction with dibromomesitylborane (MesBBr2) to afford a six‐membered dibromogermane derivative. In the presence of Lewis bases (PMe3 or MeNHC), reduction of the latter with two equivalents of potassium graphite (KC8) gives rise to cyclic (alkyl)(boryl)germylene–Lewis base adducts. Upon heating, the germylene—PMe3 adduct reacts with H2 to yield a germane, probably via a base‐free germylene featuring a small HOMO–LUMO gap. [ABSTRACT FROM AUTHOR]

A borane B(C6F5)3‐catalyzed metathesis reaction between the Si−C bond in the cyclic (alkyl)(amino)germylene (CAAGe) 1 and the Si−H bond in a silane (R3SiH; 2) is reported. Mechanistic studies propose that the initial step of the reaction involves Si−H bond activation to furnish an ionic species [1‐SiR3]+[HB(C6F5)3]−, from which [Me3Si]+[HB(C6F5)3]− and an azagermole intermediate are generated. The former yields Me3SiH concomitant with the regeneration of B(C6F5)3 whereas the latter undergoes isomerization to afford CAAGes bearing various silyl groups on the carbon atom next to the germylene center. This strategy allows the straightforward synthesis of eight new CAAGes starting from 1. [ABSTRACT FROM AUTHOR]

The reinforced concrete (RC) structural component might suffer a great damage under close-in explosion. Different from distant explosions, blast loads generated by the close-in explosion are non-uniformly distributed on the structural component and may cause both local and structural failure. In this study, an experimental study was conducted to investigate the dynamic responses of RC beams under double-end-initiated close-in explosions. The experimental results show that the distribution of blast loads generated by the double-end-initiated explosion is much more non-uniform than those generated by single-point detonation, which is caused by the self-Mach-reflection effects. A 3D finite element model was developed and validated in LS-DYNA by employing the modified K&C model. Intensive numerical calculations were conducted to study the influences of the initiation way, scaled distance and longitudinal reinforcement ratio on the dynamic responses and failure modes of RC beams. Numerical results show that the RC beam suffers greater damage as the cylindrical explosive is detonated at its double ends than the scenario in which the cylindrical explosive is detonated at its central point. RC beams mainly suffer flexural failure and flexure-shear failure under the double-end close-in explosion, and the failure modes of RC beams change from the flexural damage to flexure-shear damage as the scaled distance or the longitudinal reinforcement ratio decreases. The direct shear failure mode is not usually observed in the double-end-initiated explosion, since the intense blast loads is basically concentrated in the midspan of RC beam, which is due to self-Mach-reflection enhancement. [ABSTRACT FROM AUTHOR]

Background: The overall incidence of hyperphenylalaninemia (HPA) in China is 1:11,763, with tetrahydrobiopterin (BH4) deficiency accounting for 8.55% of patients with HPA in the mainland. Much progress has been made in the diagnosis and treatment of BH4 deficiency with the introduction of neonatal screening in China. However, the screening rate is still low and screening is not universally available. Methods: A total of 44 BH4-deficient patients were enrolled in this study, of which 39 were diagnosed with BH4 deficiency, while the remaining five showed typical characteristics of BH4 deficiency at a later period. The entire coding regions and adjacent intronic regions of GCH1, PTS, PCBD1 and QDPR genes were analyzed using target sequencing. Results: Nineteen (n=19) different mutations in the PTS gene including four novel mutations and one mutation in QDPR were identified. p.P87S, p.D96N, IVS1-291A>G, p.N52S, p.K91R, p.V56M, p.T106M and p.F40GfsX53 in PTS were the prevalent mutations with ≥3% relative frequency. The mutation p.R221X in the QDPR gene was found with relatively lower frequencies (2.27%). The remaining 12 mutations in PTS were found at relative frequencies of 1.14%. Conclusions: The results could be of value for genetic counseling and prenatal diagnosis in the patients’ families and for the molecular diagnosis of BH4 deficiencies. Furthermore, four novel mutations expand and improve the PTS mutation database. [ABSTRACT FROM AUTHOR]

Objective: Qingzaojiufei decoction (QD) is an empirical herbal formula from traditional Chinese medicine that is used for the treatment of lung-related diseases. However, the effect of QD on the growth of lung tumor cells has not been investigated. The aim of this study was to examine the antitumor activity of QD in Lewis lung carcinomas (LLC) in vivo and in vitro, and to elucidate the underlying mechanisms. Methods: The LLC cells were used to assess the antitumor activity of QD by Cell Counting Kit-8 assay in vitro. In vivo, mice were randomly assigned to 5 groups (n = 10/group): the model control (MC) group was intragastrically administered physiological saline (0.9% NaCl) twice daily from day 2 after tumor implantation for 2 weeks. The QD groups were intragastrically administered QD twice daily from 2 weeks before to 2 weeks after tumor implantation for 4 weeks. The mRNA levels were detected by quantitative polymerase chain reaction, the proteins expression was determined by immunohistochemistry or western blotting. Results: Compared with the model group, QD showed inhibition of proliferation of LLC cells and reductions in tumor weight and proliferating cell nuclear antigen protein expression. Furthermore, QD up-regulated p53 mRNA expression, and downregulated c-myc and Bcl-2 mRNA expression, while MMP-9, VEGF, and VEGFR protein expression was suppressed. Phosphorylated ERK1/2 levels were also reduced by QD in a dose-dependent manner. Conclusion: Our findings suggest that QD inhibited lung tumor growth and proliferation, by activation of tumor suppressor genes, inactivation of oncogenes, suppressing the potential for invasion and metastasis, and attenuating angiogenesis. The ERK/VEGF/MMPs signaling pathways may play an important role in QD-induced inhibition of malignant tumor cell proliferation. [ABSTRACT FROM AUTHOR]

Because the construction of the C--C bond is one of the most significant reactions in organic chemistry, the development of an efficient strategy has attracted much attention throughout the synthetic community. Among various protocols to form C--C bonds, organoboron compounds are not just limited to stoichiometric reagents, but have also made great achievements as catalysts because of the easy modification of the electronic and steric impacts on the boron center. This review presents recent developments of boron-based catalysts applied in the field of C--C bond-formation reactions, which are classified into four kinds on the basis of the type of boron catalyst: 1) highly Lewis acidic borane, B(C6F5)3; 2) organoboron acids, RB(OH)2, and their ester derivatives; 3) borenium ions, (R2BL)X; and 4) other miscellaneous kinds. [ABSTRACT FROM AUTHOR]

N-Heterocyclic phosphenium triflates (NHP-OTf) 1 serve as efficient catalysts for the regio- and chemoselective hydroboration of pyridines under ambient condition with good functional group tolerance. Mechanistic studies indicate that a boronium salt, [(Py)2·Bpin]OTf 4, is generated concomitant with NHP-H 5 via hydride abstraction from HBpin by 1 in the initial reaction step. Hydride reduction of the activated pyridine in [(Py)2·Bpin]OTf 4 by NHP-H 5 affords the 1,4-hydroboration product selectively. Thus, the phosphenium species act as a hydrogen transfer reagent in the catalytic cycle. [ABSTRACT FROM AUTHOR]

Raw signal simulators for synthetic aperture radar (SAR) in different acquisition modes have been studied individually. This letter is dedicated to presenting a method for simulating multimode SAR raw signal in a unified framework. To this end, we first simulate stripmap SAR raw signal, and then mutate the raw signal from stripmap mode into the desired acquisition mode. The acquisition mode mutation is implemented by azimuth-time-variant and range-frequency-dependent bandpass filtering. While processing in range-frequency domain brings forth high accuracy, processing in azimuth-time domain makes the method applicable for flexible antenna steering laws specified by multiple SAR acquisition modes, such as staring spotlight mode, sliding spotlight mode, and terrain observation by progressive scans mode. The proposed method is validated by the simulation results. [ABSTRACT FROM PUBLISHER]

A fluoride-anion-induced, regioselective ring expansion of benzocyclic ketones and α-aryl cycloketones has been developed via insertion of arynes into unactivated benzylic C−C bonds. This reaction provides a straightforward, transition-metal-free avenue to prepare medium ring-fused benzocarbocycles by creating 'noble' seven-, eight-, and nine-membered rings. Applications of this method in the creation of medium-sized exocyclic and inner benzocyclic olefins, nine-membered lactones, and lactams are described. [ABSTRACT FROM AUTHOR]

Cyclic (amino)(aryl)carbenes (CAArCs) result from the replacement of the alkyl substituent of cyclic (alkyl)(amino) carbenes (CAACs) by an aryl group. This structural modification leads to enhanced electrophilicity of the carbene center with retention of the high nucleophilicity of CAACs, and therefore CAArCs feature a small singlet-triplet gap. The isoindolium precursors are readily prepared in good yields, and deprotonation at low temperature, in the presence of [RhCl(cod)]2 and [(Me2S)AuCl] lead to air-stable rhodium and gold CAArC-supported complexes, respectively. The rhodium complexes promote the [3+2] cycloaddition of diphenylcyclopropenone with ethyl phenylpropiolate, and induce the addition of 2-vinylpyridine to alkenes by CH activation. The gold complexes allow for the catalytic three-component preparation of 1,2-dihydroquinolines from aniline and phenyl acetylene. These preliminary results illustrate the potential of CAArC ligands in transition-metal catalysis. [ABSTRACT FROM AUTHOR]