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C40H28O4P2, monoclinic, P21/c (no. 4), a = 10.651(3) Å, b = 16.702(5) Å, c = 11.352(4) Å, β = 112.985(5)°, V = 1859.1(10) Å3, Z = 2, Rgt (F) = 0.0807, wRref (F 2) = 0.2281, T = 296 K.

C49H52Cl2N10O6, monoclinic, P21 (no. 4), a = 12.2875(14) Å, b = 8.3031(10) Å, c = 13.1242(15) Å, β = 100.0640(10)∘ $100.0640{(10)}^{\circ }$ , V = 1318.4(3) Å3, Z = 1, Rgt ${R}_{\mathrm{g}\mathrm{t}}$ (F) = 0.0736, wRref $w{R}_{\mathrm{r}\mathrm{e}\mathrm{f}}$ (F 2) = 0.1545, T = 296 K.

C32H23OP, monoclinic, P21/n (no. 14), a = 9.1869(11) Å, b = 27.940(3) Å, c = 9.6992(11) Å, β = 107.422(2)°, V = 2375.4(5) Å3, Z = 4, Rgt(F) = 0.0486, wRref(F2) = 0.1255, T = 296 K.

C27H22BrCl2OP, monoclinic, P21/c (no. 14), a = 9.0066(2) Å, b = 15.4924(4) Å, c = 18.5110(4) Å, β = 95.487(2)°, V = 2571.06(11) Å3, Z = 4, R gt(F) = 0.0509, wR ref(F 2) = 0.1494, T = 296 K.

Technological advancements have enabled the active control of electromagnetic waves. Metalenses, known for their precision in wavefront shaping and functional versatility, represent a breakthrough in optical modulation. This study addresses the challenge of achieving dual-wavelength multifunctionality in metalens design. We developed and experimentally validated metalenses with polarization dual-function multiplexing at discrete mid-wave infrared wavelengths, demonstrating high phase fidelity and functional versatility. In addition, the proposed design method was extended to long-wave infrared wavelengths, showcasing its adaptability to different application scenarios. The application of spatial multiplexing significantly enhanced the performance of the metalenses, providing a promising solution for efficient and compact optoelectronic devices. [ABSTRACT FROM AUTHOR]

Metalenses have excellent modulation capabilities in terms of phase, amplitude, and polarization of light, significantly reducing the size and complexity of imaging systems, and showing great application prospects. However, like traditional optical meta-atoms, ordinary metalenses suffer from a significant chromatic aberration problem because it is difficult to design the phase distribution for different wavelengths on a single-layer metalens. To address this, various methods for correcting chromatic aberration in metalenses have been proposed and demonstrated, such as spatial multiplexing, material hybridization, and increasing the cross-sectional diversity of metalens meta-atoms. In this paper, a novel design method is used, which expands the parameter space by increasing the cross-sectional diversity of the metalens meta-atoms to provide the phase required for focusing different wavelengths, combined with particle swarm optimization for phase compensation. The multi-level metalens designed by this method achieves a constant and approximate focal length in the visible wavelength range of λ = 450–650 nm, with a polarization-independent absolute focusing efficiency of about 17%, and a numerical aperture (NA) of 0.31 for a lens diameter of 100 μm. This improves the imaging quality. [ABSTRACT FROM AUTHOR]

Chiral particles have attracted considerable attention due to their distinctive interactions with light, which enable a variety of cutting-edge applications. This review presents a comprehensive analysis of the optical forces acting on chiral particles, categorizing them into gradient force, radiation pressure, optical lateral force, pulling force, and optical force on coupled chiral particles. We thoroughly overview the fundamental physical mechanisms underlying these forces, supported by theoretical models and experimental evidence. Additionally, we discuss the practical implications of these optical forces, highlighting their potential applications in optical manipulation, particle sorting, chiral sensing, and detection. This review aims to offer a thorough understanding of the intricate interplay between chiral particles and optical forces, laying the groundwork for future advancements in nanotechnology and photonics. [ABSTRACT FROM AUTHOR]

Application-layer distributed denial-of-service (DDoS) attacks incapacitate systems by using up their resources, causing service interruptions, financial losses, and more. Consequently, advanced deep-learning techniques are used to detect and mitigate these attacks in cloud infrastructures. However, in mobile edge computing (MEC), it becomes economically impractical to equip each node with defensive resources, as these resources may largely remain unused in edge devices. Furthermore, current methods are mainly concentrated on improving the accuracy of DDoS attack detection and saving CPU resources, neglecting the effective allocation of computational power for benign tasks under DDoS attacks. To address these issues, this paper introduces SecEG, a secure and efficient strategy against DDoS attacks for MEC that integrates container-based task isolation with lightweight online anomaly detection on edge nodes. More specifically, a new model is proposed to analyze resource contention dynamics between DDoS attacks and benign tasks. Subsequently, by employing periodic packet sampling and real-time attack intensity predicting, an autoencoder-based method is proposed to detect DDoS attacks. We leverage an efficient scheduling method to optimize the edge resource allocation and the service quality for benign users during DDoS attacks. When executed in the real-world edge environment, our experimental findings validate the efficacy of the proposed SecEG strategy. Compared to conventional methods, the service rate of benign requests increases by 23% under intense DDoS attacks, and the CPU resource is saved up to 35%. [ABSTRACT FROM AUTHOR]

C40H28O4P2, monoclinic, P21/c (no. 4), a = 10.651(3) Å, b = 16.702(5) Å, c = 11.352(4) Å, β = 112.985(5)°, V = 1859.1(10) Å3, Z = 2, Rgt(F) = 0.0807, wRref(F2) = 0.2281, T = 296 K. [ABSTRACT FROM AUTHOR]

Benzo[b]phosphole oxides are valuable and significant organic functional molecules. Therefore, extensive efforts have been dedicated to the development of an environmentally friendly and convenient synthetic strategy for benzo[b]phosphole oxides. However, several critical issues still persist in the currently available protocols. In this study, we present a direct air-oxidized strategy enabling the transformation of arylphosphine oxides into phosphinoyl radicals, which were further utilized in the synthesis of benzo[b]phosphole oxides by combining with various alkynes. In addition, the results of DFT calculations show that phosphinoyl radical formation could involve an O2-mediated O–H bond homolysis instead of the commonly recognized P–H bond homolysis mechanism. [ABSTRACT FROM AUTHOR]

We develop a modified potential flow model (MPFM) for a circular moonpool by quantifying the viscous damping. The flow-separation-induced damping coefficients of MPFM do not need to be tuned by the users as they are derived from the conduit problem studied by Idelchik, where the variation of such coefficients with geometry configurations is given based on experiments. To verify the MPFM, we conducted laboratory experiments in heave radiation (forced harmonic heave motion) and wave diffraction (fixed in regular wave) problems with a broad range of frequencies and compared the results with those of MPFM and a boundary element method without viscosity modeling (BEM). The MPFM achieves fairly good agreement with the experimental results, including those around the resonance frequency where BEM over-predicts. A simple time-domain model is developed to analyze the sources of the different harmonics in the free-surface elevation observed in the experiment. [ABSTRACT FROM AUTHOR]

Total laparoscopic anterior resection (tLAR) and natural orifice specimen extraction surgery (NOSES) has been widely adopted in the treatment of rectal cancer (RC). However, no study has been performed to predict the short-term outcomes of tLAR using machine learning algorithms to analyze a national cohort. Data from consecutive RC patients who underwent tLAR were collected from the China NOSES Database (CNDB). The random forest (RF), extreme gradient boosting (XGBoost), support vector machine (SVM), deep neural network (DNN), logistic regression (LR) and K-nearest neighbor (KNN) algorithms were used to develop risk models to predict short-term complications of tLAR. The area under the receiver operating characteristic curve (AUROC), Gini coefficient, specificity and sensitivity were calculated to assess the performance of each risk model. The selected factors from the models were evaluated by relative importance. A total of 4313 RC patients were identified, and 667 patients (15.5%) developed postoperative complications. The machine learning model of XGBoost showed more promising results in the prediction of complication than other models (AUROC 0.90, P < 0.001). The performance was similar when internal and external validation was used. In the XGBoost model, the top four influential factors were the distance from the lower edge of the tumor to the anus, age at diagnosis, surgical time and comorbidities. In risk stratification analysis, the rate of postoperative complications in the high-risk group was significantly higher than in the medium- and low-risk groups (P < 0.001). The machine learning model shows potential benefits in predicting the risk of complications in RC patients after tLAR. This novel approach can provide reliable individual information for surgical treatment recommendations. [ABSTRACT FROM AUTHOR]

Optical tweezers (OTs) can transfer light momentum to particles, achieving the precise manipulation of particles through optical forces. Due to the properties of non-contact and precise control, OTs have provided a gateway for exploring the mysteries behind nonlinear optics, soft-condensed-matter physics, molecular biology, and analytical chemistry. In recent years, OTs have been combined with microfluidic chips to overcome their limitations in, for instance, speed and efficiency, creating a technology known as "optofluidic tweezers." This paper describes static OTs briefly first. Next, we overview recent developments in optofluidic tweezers, summarizing advancements in capture, manipulation, sorting, and measurement based on different technologies. The focus is on various kinds of optofluidic tweezers, such as holographic optical tweezers, photonic-crystal optical tweezers, and waveguide optical tweezers. Moreover, there is a continuing trend of combining optofluidic tweezers with other techniques to achieve greater functionality, such as antigen–antibody interactions and Raman tweezers. We conclude by summarizing the main challenges and future directions in this research field. [ABSTRACT FROM AUTHOR]

One-dimensional (1D) design and optimization of the impeller plays a significant role in performance improvement of the centrifugal compressor. However, most of the concentration has been paid to three-dimensional (3D) optimization of blades, few attention was focused on main control parameters determining aerodynamic performance and their optimal combination. Thus, this study innovatively developed a multidisciplinary design method combined with empirical 1D loss models, statistical analysis, and multi-optimization theory. The preliminary design of 1D parameters was developed based on empirical loss models. Besides, the analysis of variance of signal to noise ratio (SNR) was applied to find the main control parameters according to their contributions. To maximize the total pressure ratio and isentropic efficiency, the multi-objective optimization based on grey relational grade (GRG) was used to find the optimal combination of 1D parameters. The results showed that the impeller outlet width and impeller outlet radius are the most sensitive parameters affecting compressor performance. The optimal combination of 1D parameters is obtained. Compared to the initial design, the optimal impeller can reduce consumed power of 2.99%, enhance the isentropic efficiency of 1.24% at design point, and obtain the maximum increment of isentropic efficiency of 2.16% at 50 g/s operating point at 70,000 rpm. • New multidisciplinary design and multi-objective optimization method was proposed. • Analysis of variance of SNR was used to identify main control parameters affecting performance. • The optimal combination was obtained by multi-objective optimization based on GRC. • Optimal impeller has higher isentropic efficiency at design or off-design points. [ABSTRACT FROM AUTHOR]

China has experienced rapid economic growth and serious control of aerosol emissions in the past decade. Thus, the spatiotemporal variations and driving factors of aerosol optical depth (AOD) are urgently needed to evaluate the effectiveness of aerosol control activities. The innovation of this study is a detailed spatial and temporal analysis of aerosol pollution in eight major regions of China from 2010 to 2020 using the MERRA-2 AOD reanalysis product and the driving mechanism based on the Granger causality test, sensitivity, and contribution analysis. The results show that the spatial distribution of AOD varied across the areas. Divided by the Hu Line, the AOD values of the Eastern areas were significantly higher than those of the Western areas. The temporal trend in the last eleven years was dominated by a continuous decline and moderate fluctuations at both annual and seasonal scales. The relationship between socioeconomic factors and AOD drivers was more significant in economically developed regions, suggesting that China pays more attention to haze control while developing its economy. The driving relationship between AOD and temperature was weak, while wind speed and relative humidity were more influential. For vegetation factors, Granger effects were mainly observed in the Northeast, Beijing-Tianjin-Hebei, Guangdong, Central China, and Southwest regions. In the Guangdong and Southwest regions, vegetation and economic factors were the more influential drivers. This study provides a scientific basis for the detection of aerosol changes, driving mechanisms and pollution management in China. [ABSTRACT FROM AUTHOR]

Rigidly planar polycyclic phosphacycles featuring an internal dioxaphosphorane are promising photofunctional materials. However, the lack of efficient synthetic methods resulted in limited structural diversities which significantly hampered extensive study. Herein, we report a straightforward three‐component synthesis of novel dioxaphosphorane‐fused diphosphacycles with distinctive photophysical properties. Control experiments and theory calculations were performed to account for a plausible reaction mechanism. We also systematically investigated the structure‐property relationships of these unprecedented platforms by combining experiments (X‐ray analysis, optical and redox properties) and theoretical computations. Based on their unique structure and properties, a novel fluorescent switch for pH sensing was revealed by a dynamic ring‐opening/ring‐closing process. [ABSTRACT FROM AUTHOR]