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In this study, a pulsed laser operating at a wavelength of 1064 nm and with a pulse width of 100 ns was utilized for the removal of paint from the surface of a 2024 aluminum alloy. The experimental investigation was conducted to analyze the influence of laser parameters on the efficacy of paint layer removal from the aircraft skin's surface and the subsequent evolution in the microstructure of the laser-treated aluminum alloy substrate. The mechanism underlying laser cleaning was explored through simulation. The findings revealed that power density and scanning speed significantly affected the quality of cleaning. Notably, there were discernible damage thresholds and optimal cleaning parameters in repetitive frequency, with a power density of 178.25 MW/cm2, scanning speed of 500 mm/s, and repetitive frequency of 40 kHz identified as the primary optimal settings for achieving the desired cleaning effect. Thermal ablation and thermal vibration were identified as the principal mechanisms of cleaning. Moreover, laser processing induced surface dislocations and concentrated stress, accompanied by grain refinement, on the aluminum substrate. [ABSTRACT FROM AUTHOR]

Neurokinin B (NKB), a peptide encoded by the tachykinin 3 (TAC3), is critical for reproduction in all studied species. However, its potential roles in birds are less clear. Using the female chicken (c-) as a model, we showed that c TAC3 is composed of five exons with a full-length cDNA of 787 bp, which was predicted to generate the mature NKB peptide containing 10 amino acids. Using cell-based luciferase reporter assays, we demonstrated that cNKB could effectively and specifically activate tachykinin receptor 3 (TACR3) in HEK293 cells, suggesting its physiological function is likely achieved via activating cTACR3 signaling. Notably, cTAC3 and cTACR3 were predominantly and abundantly expressed in the hypothalamus of hens and meanwhile the mRNA expression of cTAC3 was continuously increased during development, suggesting that NKB-TACR3 may emerge as important components of the neuroendocrine reproductive axis. In support, intraperitoneal injection of cNKB could significantly promote hypothalamic cGnRH-Ι , and pituitary cFSHβ and cLHβ expression in female chickens. Surprisingly, cTAC3 and cTACR3 were also expressed in the pituitary gland, and cNKB treatment significantly increased cLHβ and cFSHβ expression in cultured primary pituitary cells, suggesting cNKB can also act directly at the pituitary level to stimulate gonadotropin synthesis. Collectively, our results reveal that cNKB functionally regulate GnRH/gonadotropin synthesis in female chickens. • TAC3 and its receptor (TAC3R) are predominantly expressed in the hypothalamus of hens. • TAC3 physiological function is mainly mediated by TACR3. • NKB promotes hypothalamic GnRH-Ι , and thus pituitary FSHβ and LHβ expression in female chickens. • NKB also acts directly at the pituitary level to stimulate gonadotropin synthesis. • TAC3 provides a functional compensation for the loss of Kiss1 in female chickens. [ABSTRACT FROM AUTHOR]

Adverse childhood experiences (ACEs) have been found to be related to the risk of chronic lung diseases (CLDs). However, the role of depressive symptoms (DS) in this link has not been fully examined. The present study aimed to explore the mediating effect of DS on the relationship between ACEs and CLDs. Data for this retrospective cohort study were obtained from participants enrolled in the China Health and Retirement Longitudinal Study (CHARLS). To assess DS, the 10-item Center for Epidemiological Research Depression Scale was utilized. Logistic regression was employed to explore the associations between ACEs and DS, ACEs and CLDs, as well as depressive symptoms- chronic lung diseases (DS-CLDs). Mediation analysis was conducted to assess the mediating role of DS in the relationship between ACEs and CLDs. A total of 12,277 participants, comprising 5942 males and 6335 females, were included in this study. Logistic regression analysis identified associations between ACEs and the risk of DS, CLDs, and DS-CLDs. Mediating effect analysis demonstrated that DS had partial mediating effects on the association between CLDs and 7 ACEs, including feel alone, peer bullied, self-reported poor health status, health limitations, death of siblings, physical abuse, and parental mental health. Additionally, DS fully mediated the relationship between CLDs and hunger. Our study establishes a significant association between ACEs and CLDs, as well as with DS and DS-CLDs in the elderly population. Furthermore, DS acts as a mediating factor in the ACEs and CLDs relationship. • Adverse childhood experiences are associated with chronic lung diseases. • Depressive symptoms partly mediate the link between chronic lung diseases and specific adverse childhood experiences. • Study offers insights into potential mechanisms connecting adverse childhood experiences and chronic lung diseases. [ABSTRACT FROM AUTHOR]

Background: This study aimed to investigate the association between the serum-creatinine-to-cystatin C-to-waist-circumference (CCR/WC) ratio with lung function and severe airflow limitation (SAL). Methods: The data were derived from the China Health and Retirement Longitudinal Study. Peak expiratory flow (PEF) was used as a measure of lung function parameter. Logistic and linear regression were utilized separately to evaluate the relationship between the CCR/WC ratio with PEF and SAL in baseline. Restricted cubic spline was used to explore potential non-linear associations between the CCR/WC ratio and SAL. Cox proportional-hazards models were used to assess the association between CCR/WC quartiles and the risk of new-onset SAL. Results: A total of 6105 participants were included. This study revealed a positive association between the CCR/WC ratio and lung function (PEF: β [partial coefficient]: 25.95, 95%CI: 12.72 to 39.18, p < 0.001; PEF/PEF prediction: β = 0.08, 95%CI: 0.05 to 0.12, p < 0.001) and an inverse association relationship with SAL (OR [odds ratio]: 0.64, 95% confidence interval [CI]: 0.47 to 0.85, p = 0.003). Subgroup analysis showed a significant association between the CCR/WC ratio and SAL in males (OR: 0.58, 95% CI: 0.37 to 0.90, p = 0.017) but not in females (p = 0.059). Cox regression analysis revealed a decreased risk of SAL in the quartiles (Q2–4) compared to the first quartile of the CCR/WC ratio (hazard ratios [HRs]: 0.49 to 0.73, all p < 0.05). Conclusions: This study highlights a positive association between the CCR/WC ratio and lung function, with a potential protective effect against SAL. [ABSTRACT FROM AUTHOR]

MORN proteins play a key role in the cytoskeletal structure of eukaryotes and are essential for the close arrangement of the endoplasmic reticulum and plasma membrane. A gene with nine MORN motifs (TGGT1_292120, named TgMORN2) was identified in the Toxoplasma gondii genome; it was presumed to belong to the MORN protein family and to have the function of forming the cytoskeleton, which affects the survival of T. gondii. However, the genetic deletion of MORN2 did not noticeably affect parasite growth and virulence. Using adjacent protein labeling techniques, we identified a network of TgMORN2 interactions, which mainly included endoplasmic reticulum stress (ER stress)-related proteins. In exploring these data, we found that the pathogenicity of the KO-TgMORN2 strain was significantly reduced in the case of tunicamycin-induced ER stress. Reticulon TgRTN (TGGT1_226430) and tubulin β-Tubulin were identified as interaction proteins of TgMORN2. Collectively, TgMORN2 plays a role in ER stress, which lays a foundation for further research on the function of the MORN protein in T. gondii. [ABSTRACT FROM AUTHOR]

We had shown in our previous study that TgUrm1 (ubiquitin-related Modifier 1) was involved in the regulation of anti-oxidant stress in Toxoplasma gondii by conjugating with TgAhp1. It is generally believed that Urm1 binds to target proteins through a mechanism involving Uba (ubiquitin-like activator protein). Here, we identified the TgUrm1-exclusive ubiquitin-like activator-TgUba1, which was located in the cytoplasm of Toxoplasma. TgUba1 contained three domains, including the atrophin-1 domain (ANT1), the E1-like domain (AD), and the rhodanese homology domain (RHD). We explored the interaction of TgUba1 with TgUrm1, and the AD domain was essential for the interaction of the two proteins. The TgUba1 knockout and complementary mutants were obtained based on CRISPR/Cas9 gene editing technology. The knockout of TgUba1 attenuated parasite proliferation and virulence in mice, but not invasion and egress processes, revealing the pivotal role played by TgUba1 in T. gondii survival. Meanwhile, the conjugate band of TgUrm1 was significantly reduced under oxidative stress stimulation without TgUba1, indicating that TgUba1 enhanced the targeted conjugation ability of TgUrm1 in response to oxidative stress, especially under diamide (Dia) stimulation. Furthermore, eleven TgUba1-interacting proteins were identified by proximity-based protein labeling techniques, relating them to ubiquitin-like modifications, anti-oxidative stress and metabolic regulation processes. In conclusion, TgUba1 was essential for T. gondii survival and might be a potential ubiquitin-like activator protein for TgUrm1. [ABSTRACT FROM AUTHOR]

This work investigates the interactions between oblique waves and a partially immersed double baffle. An analytical solution to this problem, based on the linear potential flow theory, has been found by utilizing the eigenfunction matching method. The resonance issues between the double baffle under the action of oblique waves is primarily investigated using this model, considering various relative widths, 2B/L (2 B is the distance between the two baffles, L is the wave length), and the relative submergence, kD (k is the wavenumber, D is the submergence of the baffles). When resonance occurs, the transmission coefficient will rapidly increase to 1. By analyzing the relationship between the transmission coefficient and the relative width 2B/L, it is found that there are different resonance points and modes. The resonance points and modes depend on the submergence of baffles kD. This study provides a formula for calculating the resonance points. For a normal incident wave, when kD is below 1.0, the 1st-order resonance occurs in the small 2B/L region, resulting in a piston motion. High-order modes exhibit different forms, with standing waves occurring for kD ≥ 0.8, progressive waves for kD ≤ 0.48, and resonant modes ranging between standing and progressive waves for 0.48 < kD < 0.8. The effects of the incident angle on the resonance point and mode under oblique waves have also been investigated. The incident angle wave affects the interval between the two neighboring resonance points, which increases to 1/cos α times of the normal incidence for an angle of α. The resonance motion under oblique waves is nearly identical to that under the normal incident waves in the transverse plane. The difference is that there is a progressive wave in the longitudinal plane under the action of oblique waves. • Due to the resonance phenomenon, the transmission coefficient periodically changes abruptly to 1 as 2B/L increases. • The submergence of double baffles kD is the key factor that affects the resonance. • The interval of higher-order resonance points is approximately equal to half of the relative width. • The first-order resonance mode is piston motion. [ABSTRACT FROM AUTHOR]

The rapid emergence of antibiotic resistance and the scarcity of novel antibacterial agents have necessitated an urgent pursuit for the discovery and development of novel antibacterial agents against multidrug-resistant bacteria. This study involved the design and synthesis of series of novel indole-benzosulfonamide oleanolic acid (OA) derivatives, in which the indole and benzosulfonamide pharmacophores were introduced into the OA skeleton semisynthetically. These target OA derivatives show antibacterial activity against Staphylococcus strains in vitro and in vivo. Among them, derivative c17 was the most promising antibacterial agent while compared with the positive control of norfloxacin, especially against methicillin-resistant Staphylococcus aureus (MRSA) in vitro. In addition, derivative c17 also showed remarkable efficacy against MRSA-infected murine skin model, leading to a significant reduction of bacterial counts during this in vivo study. Furthermore, some preliminary studies indicated that derivative c17 could effectively inhibit and eradicate the biofilm formation, disrupt the integrity of the bacterial cell membrane. Moreover, derivative c17 showed low hemolytic activity and low toxicity to mammalian cells of NIH 3T3 and HEK 293T. These aforementioned findings strongly support the potential of novel indole-benzosulfonamide OA derivatives as anti-MRSA agents. [Display omitted] • Novel indole-benzosulfonamide oleanolic acid derivatives were constructed. • Derivative c17 showed more potential than norfloxacin against MRSA. • Derivative c17 could disrupt cell membrane and restrain metabolism. • Derivative c17 showed antibacterial efficacy in MRSA-infected skin murine model. [ABSTRACT FROM AUTHOR]

Accurately determining the extreme wave forces acting on marine structures is crucial for ensuring their safety. This study investigates the maximum values and transfer functions of wave forces on a fixed vertical truncated cylinder under focused waves through experimental analysis and numerical simulations. Firstly, an experiment was conducted to examine the influence of the wave steepness k p A p , structural scale D / L p and depth of submergence S 2 / d on both the horizontal and the vertical forces exerted on the cylinder. These factors were found to significantly influence the maximum values and transfer functions of the wave forces, particularly those of the vertical force during wave slamming events. To further understand the interactions between the focused waves and the vertical truncated cylinder, a numerical model based on the Reynolds-Averaged Navier-Stokes (RANS) equations in OpenFOAM was employed considering different heights above the surface of static water S 1 / d and varying depths of submergence S 2 / d. The validity of this model was confirmed by comparing its results with those of the experiment. Following this, the effects of S 1 / d and S 2 / d on the maximum values as well as the transfer functions of wave forces on the cylinder were discussed, including in scenarios involving wave slamming and wave overtopping events. Finally, an empirical formula for calculating the wave force was proposed, taking into account the influence of k p A p , S 1 / d , and S 2 / d on the inertial coefficient C M and the coefficient of pressure correction C P. The results demonstrated that this formula can be used to accurately predict the maximum wave forces exerted on the cylinder. • A series of physical experiments and numerical simulations for wave forces on a vertical truncated cylinder under focused waves were conducted. • The effect of wave conditions and depths of submergence of the cylinder on wave forces was analyzed. • The effect of the wave slamming or wave overtopping on wave forces of the cylinder was simulated. • An empirical formula was proposed to predict wave forces, accounting for wave conditions, height above the SWL and submergence depth of the cylinder. [ABSTRACT FROM AUTHOR]

Most of the studies on extreme waves are focused on the systems with single-peak wave spectra. However, according to the statistics of occurrence, the bimodal spectral system is also frequent in real sea conditions. In order to summarize the statistics of extreme waves, irregular wave trains under single-peak and bimodal spectra for long durations are simulated in this paper, based on a two-dimensional High Order Spectral (HOS) numerical wave tank. A large number of configurations have been tested under unimodal and bimodal spectra. The investigation on the wave trains under single-peak spectrum indicates that although in conditions often referred as deep water (kph > π), the relative water depth has a significant influence on the probabilities of occurrence of extreme waves. A detailed analysis of the combined effect of Benjamin-Feir Index (BFI) and relative water depth is provided. However, the situation is more complex in real sea conditions, which may exhibit multimodal spectra. We focus in this study on long-crested bimodal spectra characterized by the same significant wave height Hs and mean zero-crossing period Tz of the sea states as the single-peak spectrum. The wave conditions under bimodal spectrum present milder extreme wave statistics than those under single-peak spectrum. In addition, mixed ocean systems with equivalent energy distribution (i.e., Sea-Swell Energy Ratio (SSER) is close to 1.0) and larger separation between partitions (i.e., Intermodal Distance (ID) > 0.10) are the less prominent to extreme waves appearance. The comparison of the mixed sea states and the corresponding single independent systems demonstrates that the complexity of the underlying physics of a given sea state (for instance the presence of modulational instability or other nonlinear process) cannot be deduced by an analysis limited to the statistical content of the combined sea state. The wave energy being distributed among frequencies plays a major role. Additionally, Gram-Charlier distribution can accurately predict the probability of large waves (1.5 < H/Hs < 2.0) compared to the MER distribution, but it underestimates the statistics of the wave height distribution when H/Hs is larger than 2.0 for both single-peak and bimodal states. [ABSTRACT FROM AUTHOR]

The regeneration of stock land has gradually occupied the mainstream of China's urban development. In order to cope with the inherent complexity of land property rights and transaction costs in stock land regeneration, relevant urban policies need to play a necessary guiding role. Taking the downtown area of Tianjin as an example, this paper discusses the interaction between spatial regeneration and policy change of stock industrial land. Firstly, a spatial database is constructed through multi-party research to quantitatively describe the spatial and temporal evolution of the stock industrial land since 1995. Secondly, the relevant urban policies since 1979 are sorted out, and the characteristics of policy changes are evaluated and analyzed. Finally, through comparative studies, it is confirmed that the regeneration rate of stock industrial land is affected by policy change, and the speed of policy impact is subject to the policies' inherent characteristics, namely, "guiding policy" or "regulating policy." [ABSTRACT FROM AUTHOR]

In our previous paper (Li et al., 2022), the hydrodynamic characteristics of the underflow breakwater with two identical baffles were experimentally studied. In this work, the properties of an underflow breakwater with two unequal baffles on the front and back sides is investigated with respect to the hydrodynamic characteristics of this type of breakwater. Different parameters, including the relative blockage of front baffle, breakwater width, relative water depth, and two water surface states between two baffles, is considered under the regular and irregular waves. First, the resonance phenomenon is analyzed under the regular wave conditions. It has been observed that the resonance period is influenced by the width of the breakwater and the minimum relative blockage between the two baffles. The resonance has significant influence on the hydrodynamics of the breakwater characteristics. Thereafter, the transmission coefficient and reflection coefficient are studied. The transfer function of the breakwater under irregular wave is calculated. The transfer functions of different frequency spectrums are nearly identical and coincide with the transmission coefficients under regular waves. The results also indicate that this type of breakwater provides a better protection against short-period waves, whereas its effectiveness in the protecting against long-period waves is relatively weak. The results can be employed as a reference for practical engineering. • The hydrodynamic characteristics of an underflow breakwater with two unequal baffles were experimentally investigated. • The resonance phenomenon, transmission coefficient, reflection coefficient, and transfer functions were analyzed. • The resonance period depends on both the minimum relative blockage of the two baffles and the breakwater width. • The transfer function of the irregular waves can be calculated using the regular wave transmission coefficients. [ABSTRACT FROM AUTHOR]

In this paper, wave transformation over a submerged reef has been numerically studied based on the OpenFOAM model. This numerical model solves the Reynolds-Averaged Navier-Stokes equations for two-phase flow and employs the volume of fluids (VOF) method for the free surface. The k-ω SST turbulence model is used to simulate wave breaking, and the wave generation library waves2Foam is adopted to generate waves in the model. The numerical model is first validated against the physical experimental data, and it is shown that the model is capable of simulating the key processes of wave shoaling, breaking and transmission over the submerged reef. Then, a series of numerical tests are conducted considering different incident wave heights, submergences and slopes of the reef. The influences of reef slope and submergence on the wave properties over the reef are discussed, which include the wave reflection and transmission coefficients, breaking wave height, wave-induced setup, and energy dissipation. [ABSTRACT FROM AUTHOR]

The estimation of wave run-up is a concern in the design of certain marine engineering structures. Accurate estimation of the wave run-up is important for the safety and cost of the structure. To better predict the wave run-up on structures, a series of physical experiments for wave run-up on vertical cylinder under regular waves and focusing waves were conducted in this study. The influences of the wave steepness kA , relative structural scale ka , and A / D on the wave run-up were analyzed. By fitting the experimental data, a semi-empirical formula that calculates the wave run-up, based on the velocity stagnation head theory, is proposed. In the improved formula, a second order theory is employed to calculate the wave velocity in the crest, and the two important factors, viz., the relative structural scale ka and A / D, are also considered. The formula was evaluated by utilizing certain experimental data in the literature, demonstrating that it can provide a satisfactory wave run-up prediction. Furthermore, the wave run-up on the cylinder under the focused waves was predicted by the new formula. It can predict it well as local wave steepness is small. • A series of physical experiments for wave run-up on vertical cylinder under regular waves and focusing waves were conducted. • A semi-empirical formula that calculates the wave run-up, based on the velocity stagnation head theory, is proposed. • The two parameters ka and A /D are considered in the improved formula. • The formula was evaluated by utilizing certain experimental data in the literature. [ABSTRACT FROM AUTHOR]

Particle size distribution is essential for describing direct and indirect radiation of aerosols. Because the relationship between the aerosol size distribution and optical thickness (AOT) is an ill-posed Fredholm integral equation of the first type, the traditional techniques for determining such size distributions, such as the Phillips-Twomey regularization method, are often ambiguous. Here, we use an approach based on an improved particle swarm optimization algorithm (IPSO) to retrieve aerosol size distribution. Using AOT data measured by a CE318 sun photometer in Yinchuan, we compared the aerosol size distributions retrieved using a simple genetic algorithm, a basic particle swarm optimization algorithm and the IPSO. Aerosol size distributions for different weather conditions were analyzed, including sunny, dusty and hazy conditions. Our results show that the IPSO-based inversion method retrieved aerosol size distributions under all weather conditions, showing great potential for similar size distribution inversions. [ABSTRACT FROM AUTHOR]

Recently, with the enhancement of marine environmental protection, the permeable breakwater, which has the advantages of a simple structure, good water permeability, and environment-friendly, has been paid more and more attention. This study experimentally investigated the hydrodynamic characteristics of a twin vertical baffles underflow breakwater in a wave flume. Different parameters including the relative submergence, relative blockage, breakwater width, and water surface condition between baffles have been considered. Their influences on the transmission coefficient, reflection coefficient, relative wave run-up on the front baffle, and energy loss rate of the twin vertical baffles underflow breakwater have been analyzed. Furthermore, the wave resonance phenomenon could occur for the cases with free water surface between the two baffles, which had a significant influence on the hydrodynamic characteristics of the breakwater. Finally, an empirical formula for calculating the transmission coefficient has been given based on the experimental data. • The hydrodynamic characteristics of a twin vertical baffles underflow breakwater were experimentally investigated. • The transmission coefficient, reflection coefficient, relative wave run-up, and energy loss rate have been analyzed. • The wave resonance phenomenon had a significant influence on the hydrodynamic characteristics of the breakwater. • An empirical formula for calculating the transmission coefficient has been given based on the experimental data. [ABSTRACT FROM AUTHOR]

In this investigation of the groupiness properties of unstable random wave trains, the evolution of wave groups in the process of freak wave generation and their scale-averaged wavelet power W ( t ) are analyzed. Wave groupiness is described in terms of two new groupiness parameters, group height GF W and group length GL W , which are defined based on the wavelet transform. The relationship between GF W , GL W and the kurtosis of the wave surface are also given. Detailed analyses show that wave groups play an important role in the process of freak wave generation. The group height parameter GF W reflects the wave train instability well. More unstable wave trains (i.e., those with a larger Benjamin–Feir index) are reflected in larger values of GF W , which gradually increases with wave evolution during wave propagation; however, GL W is not obviously related to wave instability but is associated with the bandwidth of the frequency spectrum. The ratio of GF W to GL W is strongly related to kurtosis, implying that it is a good indicator of freak wave generation. [ABSTRACT FROM AUTHOR]

When a large wave interacts with a marine structure, it would lead to a high-frequency structure response, and impose great threats to marine structures. In this paper, wave forces on a vertical cylinder in regular waves with moderate to extreme steepness were measured experimentally. The secondary load cycle phenomenon in wave force time history was observed and its generation mechanism was analyzed. It is found that secondary load cycle strongly depends on wave steepness. When the wave steepness exceeds critical values, the secondary load cycle phenomenon appears in the time history of wave force, and a high frequency response accompanied this phenomenon. Further, a new critical wave steepness kA = 0.3tanh(kh) (A is wave crest height, k is wavenumber and h is water depth) is found to distinguish the secondary load cycle occurrence. Here the wave steepness threshold value is no more a constant value that was proposed before, it varies with water depth and becomes smaller with the decrease of water depth. Moreover, the secondary load cycle and the subsequent high-frequency response are divided from the wave force signal based on the empirical mode decomposition (EMD) method. The results show that the high-frequency response locates in the natural frequency region of cylinders, which is much higher than the high-order wave components. Finally, the generation mechanism of this phenomenon is explained. As a steep wave passes a cylinder, a large wave run-up would be generated on the front side of the cylinder. One part of water body of the run-up swashes down and impacts the wave surface heavily. The other part of wave run-up fills into the cavity on the lee side of the cylinder, and generates violent turbulence. Both processes are found to lead to an instant impact on the structure, and then excite structural high-frequency vibration. This instant impact expresses as secondary load cycle in wave force history. These new findings from experimental studies have provided new insights into the generation mechanism and the associated changes in wave properties during the formation of secondary load cycle. • Wave forces on a vertical cylinder in regular waves with moderate to extreme steepness are measured experimentally. • A new critical wave steepness kA = 0.3tanh(kh) is found to distinguish the secondary load cycle occurrence. • The secondary load cycle and the high-frequency response are divided based on the empirical mode decomposition method. • The generation mechanism of secondary load cycle is explained. [ABSTRACT FROM AUTHOR]

Abstract: We describe experiments with multi-directional focused waves interacted with a vertical circular cylinder in a 3D wave basin. The focus of this study is on the run-up of multi-directional focused waves, wave forces, and wave pressures on the cylinder. Part I, the study on wave run-up, has already been presented by Li et al. (2012). In this paper, the analysis of the wave force on the vertical cylinder is presented. In this experiment, a cylinder with 0.25m in diameter was adopted and different wave parameters, such as focused wave amplitude, peak frequency, frequency bandwidth and directional spreading index, are considered. The model scale kpa (kp is the wave number corresponding to peak frequency, a is the radium of the cylinder) varies from 0.32 to 0.65. The maximum forces of multi-directional focused wave on cylinder were measured and investigated. The results showed that the wave parameters have a significant influence on the wave force, and that the spatial profile of the surface of multi-directional focused wave can also affect its force on the cylinder, which is different from two-dimensional wave. In addition, the ‘secondary loading cycle’ phenomenon was also observed and discussed. In our experiments, the ‘secondary loading cycles’ occur when kA >0.36 for all cases. While in some referred small scale experiments, the secondary load cycles are observed even for kA =0.2, when the waves are longer enough. To larger model scale, the pronounced secondary load cycle occurs with larger wave steepness waves. [Copyright &y& Elsevier]

Inspired by the focusing principle of a parabolic-type mirror and the wave Bragg resonance, a parabolic-type spatial layout with a Bragg bottom is proposed, which can significantly amplify wave height. The wave propagation characteristics on the parabolic-type topography were numerically investigated using a developed numerical model based on the High-Order Spectral (HOS) method. The amplification properties of the wave height on the proposed parabolic topography with a Bragg bottom were systematically analyzed considering different ripple heights, ripple numbers, topographic widths and focal lengths. The results show that the focusing effect of wave height increases with the increase of the ripple height, ripple number and topographic width. However, when the ripple number and topographic width are bigger than certain constants, their effect on wave focusing becomes insignificant. Compared with the traditional parallel-type layout, the ripple number of the proposed parabolic-type layout can be reduced to one-fifth to achieve the same amplified effect of the parallel layout with the same ripple height. Moreover, the focus length also influences the wave focusing by changing the wave collection angle. From the presented studies, the optimal collection angle of the parabolic-type layout is approximately in the range of 82°–115°. • A parabolic-type spatial layout with a Bragg bottom is proposed. • The wave amplification properties on the proposed topography were analyzed. • The proposed parabolic-type layout magnification effect is generally better than traditional layout. • The optimal collection angle of the parabolic-type layout is approximately in the range of 82°–115°. [ABSTRACT FROM AUTHOR]

Abstract: The heave plate is the key component of a Spar platform as it can effectively improve the heave response of the platform system by providing additional damping and added mass. This paper investigates the hydrodynamic coefficients of heave plates by using forced oscillation model tests. The effects of variables such as the Keulegan–Carpenter (KC) number, frequency of oscillation, plate depth, thickness-to-width ratio, shape of the edge, perforation ratio and hole size on the hydrodynamic coefficients were analyzed. Experiments using a group of three solid or perforated heave plates were also carried out and the experimental results were compared with those for a single plate. The relationship between the spacing of the heave plates and hydrodynamic coefficients was studied. [Copyright &y& Elsevier]

Abstract: A wave basin experiment has been performed to investigate the interactions between multi-directional focused wave and vertical bottom-mounted cylinder. In this paper, a study on wave run-up on a vertical bottom-mounted cylinder is presented. For all experimental cases, the ratio of the water depth and cylinder diameter ratio (d/D) is equal to 2.0 and the ratio of the wave height and water depth (2A/d) is varied in the range of (0.12, 0.60), where A is the focused amplitude. The experimental results showed that the focused wave parameters, including wave steepness, frequency bandwidth, and directional spreading index, had significant impacts on the wave run-up on a cylinder. More specifically, the focused wave run-up increased as these parameters increased, and the maximum value of the measured wave run-up ratio could be as high as 1.68. The variations of the multi-directional focused wave run-up around the cylinder were also analyzed. The wave run-up at the front of the cylinder was greater than that at the other positions around the cylinder. The wave run-up reached the lowest values at 135°. The associated focused wave parameters also impacted the wave run-up distribution around the cylinder. [Copyright &y& Elsevier]

Backgrounds: To our knowledge, there is no available nationwide data on omicron symptom patterns in China mainland. We aim to determine the acute and long COVID-19 symptoms in the omicron-dominant period and to evaluate its association with risk factors. Methods: We designed a cross-sectional nationwide study and data about self-reported symptoms were collected by an online platform named Wenjuanxing. Eligible participants were aged 25–65 years and were symptomatic. In this study, the ratios of the number of people of different ages and genders were weighted by the data from the Seventh National Census (2020 years), and validated by a published nationwide representative study through comparing smoking rates. Descriptive indicators were calculated for demographic characteristics, diagnosis ways, and duration time, acute symptoms, hospitalization, severity and long COVID-19 symptoms. And, the associations between risk factors and acute and long COVID-19 symptoms were analyzed by multivariable logistic regression models. Results: A total of 32,528 individuals diagnosed as COVID-19 infection from October 1, 2022 to February 21, 2023 were included. The first three acute symptoms of COVID-19 infection were fever (69.90%), headache (62.63%), and sore throat (54.29%), respectively. The hospitalization rate within 7 days was 3.07% and symptoms disappearance rate within 21 days was 68.84%, respectively. Among 3983 COVID-19 patients with 3 months or more time difference between first infection and participation into the study, the long COVID-19 rate was 19.68% and the primary symptoms were muscle weakness (19.39%), headache (17.98%) and smell/taste disorder (15.18%). Age groups, smoking, marriage status and vaccination were risk factors for numbers of acute phase symptoms and long COVID-19 symptoms. Lastly, female and current smokers also showed more numbers of symptoms during acute infection period. Conclusions: In Chinese mainland, our respondent indicated that current smokers and women were associated with acute COVID-19 symptoms, which should be treated with caution due to the lack of representative. [ABSTRACT FROM AUTHOR]

Understanding the evolution of rural landscapes in metropolises during rapid urbanization is crucial for formulating policies to protect the rural ecological environment. In this study, remote sensing and geographical information system data, as well as applied landscape index analysis, are used to examine the spatiotemporal evolution of rural landscape patterns in the Beijing-Tianjin region of China, which has experienced rapid urbanization. The relationships between land use/land cover changes and changes in rural landscape patterns are explored. The results revealed significant spatial differences in the rural landscapes in the Beijing-Tianjin region; farmland and forestland were the main types of landscapes, creating a "mountain-field-sea" natural landscape pattern. The conversion of rural landscapes in the Beijing-Tianjin region involved mainly the conversion of farmland to urban areas, with few exchanges between other landscape types. The urban areas in the Beijing-Tianjin region increased by 3% per decade; farmland decreased at the same rate. Additionally, the rural landscape patterns in the Beijing-Tianjin region were dominated by fragmentation, dispersion, and heterogeneity and moved from complex to regular. Water bodies displayed the most fragmented natural landscape; their number of patches increased by 36%, though their network characteristics were maintained. Forestland was the most concentrated natural landscape. In this study, theoretical support and a scientific reference for the optimization of rural landscape patterns and the improvement in rural living environments in rapidly urbanizing areas are provided. [ABSTRACT FROM AUTHOR]

Rice eating and cooking quality (ECQ) is one of the most important qualities and it has attracted more and more interests of consumers and breeders. SSIIa and Wx are the major genes affecting rice ECQ, and several alleles of SSIIa and Wx have been identified. In this study, the effects of different allele combinations of SSIIa and Wx on rice ECQ were explored by analyzing amylose content (AC), gelatinization temperature (GT), and Rapid Viscosity Analyzer (RVA) profile properties of one natural population which is composed of 30 glutinous rice varieties and 342 non-glutinous varieties. Nine allele combinations of SSIIa and Wx were identified in all the non-glutinous varieties. The allele combination of SSIIac/Wxb harbored higher BDV, lower SBV, intermediate AC, and higher GT, which means better taste quality but more cooking time. For non-glutinous rice, stepwise regression analysis showed that RVA profile properties are mainly controlled by polymorphic loci of Wx-Int1(G/T) and Wx-EX10(C/T); AC, PV, BDV, and SBV are mainly controlled by Wx-Int1(G/T); HPV, CPV, and CSV are mainly controlled by Wx-EX10(C/T); GT is mainly controlled by SSIIa-EX8(GC/TT). Regression equation models also confirmed that SSIIac/Wxb had better ECQ compared to other allele combinations, indicating its potential to improve rice quality. Our results may provide useful clues for elite alleles of SSIIa and Wx for introgression to other rice varieties to improve rice ECQ. [ABSTRACT FROM AUTHOR]

Leaf blast is recognized as one of the most devastating diseases affecting rice production in the world, seriously threatening rice yield. Therefore, early detection of leaf blast is extremely important to limit the spread and propagation of the disease. In this study, a leaf blast-specific spectral vegetation index RBVI = 9.78 R 816 − R 724 − 2.08( ρ 736 / R 724 ) was designed to qualitatively detect the level of leaf blast disease in the canopy of a field and to improve the accuracy of early detection of leaf blast by remote sensing by unmanned aerial vehicle. Stacking integrated learning, AdaBoost, and SVM were used to compare and analyze the performance of the RBVI and traditional vegetation index for early detection of leaf blast. The results showed that the stacking model constructed based on the RBVI spectral index had the highest detection accuracy (OA: 95.9%, Kappa: 93.8%). Compared to stacking, the detection accuracy of the SVM and AdaBoost models constructed based on the RBVI is slightly degraded. Compared with conventional SVIs, the RBVI had higher accuracy in its ability to qualitatively detect leaf blast in the field. The leaf blast-specific spectral index RBVI proposed in this study can more effectively improve the accuracy of UAV remote sensing for early detection of rice leaf blast in the field and make up for the shortcomings of UAV hyperspectral detection, which is susceptible to interference by environmental factors. The results of this study can provide a simple and effective method for field management and timely control of the disease. [ABSTRACT FROM AUTHOR]

The differences in geomechanical properties and the uncertainty in the spatial distribution of Bimrock pose significant challenges to the construction and disaster prediction of geotechnical engineering. To clarify the geomechanical characteristics of Bimrock, this paper summarizes the basic concepts and classification methods of Bimrock at home and abroad. It discusses the methods and characteristics of determining the geometric features of Bimrock blocks and explores the influencing factors and laws of failure modes and strength under different stress states of Bimrock. The study finds that the failure mode of Bimrock is mainly influenced by factors such as block proportion, degree of welding between blocks and matrix, strength ratio between blocks and matrix, and geometric properties of blocks. Among these factors, block proportion is the most significant, and the degree of welding is a controlling factor. However, due to the complexity of Bimrock structures, there is a lack of applicable methods and mechanical models for the evaluation of geomechanical characteristics of Bimrock in engineering practice. This article also explores the influence and research methods of the geological characteristics of Bimrock in slope and tunnel engineering and, finally, provides prospects for the future research trends relating to Bimrock. [ABSTRACT FROM AUTHOR]

Difficulties of in vitro culture and genetic manipulation of Eimeria tenella have hindered the screening of virulence factors in this parasite. In this study, the E. tenella rhoptry protein 30 (EtROP30) was expressed in Toxoplasma gondii (RH∆Ku80-EtROP30), and its effect on the proliferation and virulence of parasites was investigated. The results revealed that the expression of EtROP30 had no impact on the invasion and egress processes. However, the RH∆Ku80-EtROP30 strain formed larger plaques compared to the RH∆Ku80, indicating that the EtROP30 expression promotes T. gondii proliferation. Furthermore, the RH∆Ku80-EtROP30 strain exhibited greater pathogenicity, resulting in earlier mortality and shorter overall survival time compared to RH∆Ku80. These results imply that EtROP30 expression facilitates parasite intracellular proliferation and virulence in mice, suggesting that EtROP30 might be a candidate virulence factor of E. tenella. [ABSTRACT FROM AUTHOR]

A series of wave basin experiments have been conducted to investigate the interactions between short-crested waves and complex pile groups. A statistical analysis of the interactions between short-crested random waves and a pile group with nine piles in a side-by-side arrangement has been shown in our previous study. As a parallel study, the short-crested random wave action on a pile group with eight small-scale piles in a double-row side-by-side arrangement is experimentally investigated in this paper. Variations in the coefficients of the pile group effect with the KCLD1/3 parameter and standard deviation σθ of directional spreading are given. The relations of the inline force, transverse force, and resultant force are illustrated, and the wave loading of the piles in the group is ascertained. The results show that wave directionality plays an important part in the short-crested random wave action on pile group structures, especially on the transverse force of the piles. The pile group effect in a double-row side-by-side arrangement is weaker than that in simply a one-row side-by-side arrangement due to interactions between the rows of the piles. [ABSTRACT FROM AUTHOR]

• A FEM model is established based on modified Boussinesq equations to simulate wave propagation and breaking. • The incident wave heights increase for different periods to catch different kinds of wave breaking. • Oblique regular and irregular incident waves and multidirectional waves are considered. • The initial breaking threshold parameter should take different values for oblique and multidirectional waves. Creating a representative numerical simulation of the propagation and breaking of waves along slopes is an important problem in engineering design. Most studies on wave breaking have focused on the propagation of normal incident waves on gentle slopes. In practice, however, waves on steep slopes are obliquely incident or multidirectional irregular waves. In this paper, the eddy viscosity term is introduced to the momentum equation of the improved Boussinesq equations to model wave dissipation caused by breaking and friction, and a numerical model based on an unstructured finite element method (FEM) is established based on the governing equations. It is applied to simulate wave propagation on a steep slope of 1:5. Parallel physical experiments are conducted for comparative analysis that considered a large number of cases, including those featuring of normal and oblique incident regular and irregular waves, and multidirectional waves. The heights of the incident wave increase for different periods to represent different kinds of waves breaking. Based on examination, the effectiveness and accuracy of the numerical model is verified through a comprehensive comparison between the numerical and the experimental results, including in terms of variation in wave height, wave spectrum, and nonlinear parameters. Satisfactory agreement between the numerical and experimental values shows that the proposed model is effective in representing the breaking of oblique incident regular waves, irregular waves, and multidirectional incident irregular waves. However, the initial threshold of the breaking parameter η t (I) takes different values for oblique and multidirectional waves. This needs to be paid attention when the breaking of waves is simulated using the Boussinesq equations. [ABSTRACT FROM AUTHOR]

Abstract Pile groups are widely used structures in coastal and ocean engineering, such as in cross-sea bridges and offshore wind turbine foundations. The effect of a pile group must be considered when calculating the wave forces on piles. In addition, real sea waves are multi-directional waves. However, the associated regulations and studies have mainly concentrated on the action of a unidirectional wave on pile groups. Few studies have considered the interactions between multi-directional irregular waves and pile groups. In this study, we experimentally investigated the interactions between multi-directional irregular waves and a small scale, vertical bottom-mounted pile group comprising nine piles in a side-by-side arrangement. We propose a new parameter: KC LD 1/3 = KC 1/3 × L / D , to comprehensively consider the effects of the relative pile diameter D/L and KC 1/3 number on the wave inline force and transverse force on piles. The results show that directional spreading has a significant effect on the interaction between multi-directional irregular waves and piles, especially on the transverse force of piles. The relationships between the inline force, transverse force, and resultant force are studied, and the differences in the wave force among different piles are determined. These results may provide a reference to facilitate the design of engineering structures. Highlights • Experimental investigations of the interactions between irregular waves and a side-by-side pile group are carried out. • A new parameter called the KC LD 1/3 number is proposed to measure the pile group effect. • The wave directionality has a noticeable effect on the wave force of the pile group structure. • These results may provide a reference to facilitate the design of engineering structures. [ABSTRACT FROM AUTHOR]

In this study, the interactions between multi-directional irregular waves and a tandem pile group are experimentally investigated. A systematic statistical analysis of the force coefficients of the pile group and the wave force on a tandem pile group under multi-directional waves is first carried out. The results show that the wave force of the pile group is significantly affected by the wave directionality. Further, Reynolds-averaged Navier–Stokes equations are used to establish a 3D numerical wave tank by considering the interactions between the waves and the pile groups, and this is verified by using experimental data. The characteristics of the wave force on the first and the last pile in the tandem pile group were numerically examined. The flow field around the front first pile was affected by its rear pile such that the pressure at its rear increased. However, without the rear pile, the pressure difference between the upward and rearward zone of the last pile significantly increased compared with that of the first pile, and this caused the wave force of the last pile to be larger than that of the first pile. [ABSTRACT FROM AUTHOR]

A large number of studies have shown that matrine (MA) possesses various pharmacological activities and is one of the few natural, plant-derived pesticides with the highest prospects for promotion and application. Fifty-eight MA derivatives were prepared, including 10 intermediates and 48 target compounds in 3 series, to develop novel mosquitocidal agents. Compounds 4b, 4e, 4f, 4m, 4n, 6e, 6k, 6m, and 6o showed good larvicidal activity against Aedes albopictus, which is both a highly aggressive mosquito and an important viral vector that can transmit a wide range of pathogens. Dipping methods and a bottle bioassay were used for insecticidal activity evaluation. The LC50 values of 4e, 4m, and 6m reached 147.65, 140.08, and 205.79 μg/mL, respectively, whereas the LC50 value of MA was 659.34 μg/mL. Structure–activity relationship analysis demonstrated that larvicidal activity could be improved by the unsaturated heterocyclic groups introduced into the carboxyl group after opening the D ring. The MA derivatives with oxidized N-1 lost their mosquitocidal activities, indicating that the bareness of N-1 is crucial to maintain their anti-mosquito activity. However, the activity was not greatly influenced by introducing a cyan group at C-6 or a benzene sulfonyl group at N-16. Additionally, compounds 4e and 4m exhibited good inhibitory activities against acetylcholinesterase with inhibitory rates of 59.12% and 54.30%, respectively, at a concentration of 250 μg/mL, whereas the inhibitory rate of MA was 9.88%. Therefore, the structural modification and mosquitocidal activity of MA and its derivatives obtained here pave the way for those seeking strong mosquitocidal agents of plant origin. [ABSTRACT FROM AUTHOR]

Simple Summary: Sophoridine, a natural quinolizidine alkaloid with biological activities, was isolated and identified from traditional medicinal herbs. Although mosquitoes can be effectively controlled by chemical insecticides, their intense use has significantly increased the development and spread of resistant mosquitoes. Chemical insecticides have negative effects, such as potential health risks, water contamination, environmental pollution, and toxicity to nontarget organisms, including people. In this study, two series of sophoridine derivatives were generated using sophoridine as the lead compound. All derivatives were characterized and screened for their insecticidal activity against larva and adult mosquitoes. Their effects on the growth cycle of larva and their action on AChE from Aedes albopictus were also explored. Finally, morphological studies of the derivative-treated dead larvae were conducted. Two series of novel sophoridine derivatives were designed, synthesized, and evaluated for their anti-mosquito activity. SOP-2g, SOP-2q, and SOP-2r exhibited potential larvicidal activity against Aedes albopictus larva with LC50 values of 330.98, 430.53, and 411.09 ppm, respectively. Analysis of structure–activity relationships indicated that the oxime ester group was beneficial for improving the larvicidal biological activity, whereas the long-chain aliphatic group and fused-ring group were introduced. Furthermore, the larvicidal mechanism was also investigated based on the inhibition assay of acetylcholinesterase (AChE) and the morphological observation of dead larva treated with derivatives. Results indicated that the AChE inhibitory activity of the preferred three derivatives were 63.16%, 46.67%, and 35.11%, respectively, at 250 ppm concentration. Additionally, morphological evidence demonstrated that SOP-2q and SOP-2r induced changes in the larva's intestinal cavity, caudal gill, and tail, thereby displaying larvicidal action against Ae. albopictus together with AChE inhibition. Therefore, this study implied that sophoridine and its novel derivatives could be used to control the population of mosquito larva, which may also be effective alkaloids to reduce the mosquito population density. [ABSTRACT FROM AUTHOR]

Spexin (SPX) is a conservative tetradecapeptide which has been proven to participate in multiple physiological processes, including anxiety, feed intake, and energy metabolism in fish and mammals. However, whether SPX exists and functions in birds remain largely unknown. Using chicken (c-) as a model, the full-length cDNA encoding cSPX precursor was cloned, and it was predicted to generate a mature peptide with 14 amino acids conserved across vertebrates. The pGL4-SRE-luciferase reporter system-based functional analysis demonstrated that cSPX was effective in activating chicken galanin type Ⅱ receptor (cGALR2), cGALR2-like receptor (cGALR2L) and galanin type Ⅲ receptor (cGALR3), thus to stimulate intracellular MAPK/ERK signaling pathway. Quantitative real-time PCR revealed that SPX was widely expressed in chicken tissues, especially abundant in the central nervous system, pituitary, testes, and pancreas. Interestingly, it was noted that chicken hypothalamic SPX mRNA could be up-regulated by 24-h and 36-h fasting, heralding its latent capacity in appetite regulation. In accordance with this speculation, peripheral injection of cSPX was proved to be functional in reducing feed intake of 3-wk-old chicks. Furthermore, we found that cSPX could reduce the expression of AgRP and MCH , with a concurrent rise in CART1 mRNA level in the hypothalamic of chicks. Collectively, our findings not only provide the evidences that SPX can act as a satiety factor by orchestrating the expression of key feeding regulators in the chicken hypothalamus but also help to facilitate a better understanding of its functional evolution across vertebrates. [ABSTRACT FROM AUTHOR]

Nonlinear interaction dominates the whole process from wave deformation to breaking, and is one of the significant factors that may cause many unstable changes in waves. This study aims to indicate the nonlinear characteristics of waves generated by submerged jets. The time series of those waves under five dimensionless upstream water depths (l = 3.0, 4.0, 4.5, 5.0, 5.5) are measured experimentally. Moreover, the wave surface asymmetry, skewness, spectrum, and wavelet-based bicoherence are obtained. The results show that the amplitude of wave surface varies with the variation of measuring point position and upstream water depth. From the perspective of asymmetry and skewness, the wave surface varies from tilt forward to tilt backward along the propagation path, and the vertical tilt amplitude decreases gradually; meanwhile, except for few measuring points, it is basically negative skewness. It can be seen from the energy spectrum that the wave energy increases with the increase of upstream water depth and decreases with the propagation of wave surface. In addition, the wavelet-based bicoherence distribution shows that the energy transfer caused by the interaction between waves is weak. The findings can provide an improved understanding of the nonlinearity characteristics of waves generated by submerged jets. • The nonlinear characteristics of waves generated by submerged jets are investigated experimentally. • The Hilbert transform and continuous wavelet transform are conducted to obtain the nonlinear parameters of waves. • The nonlinear characteristics and their temporal variations are discussed. • The findings can provide an improved understanding of the nonlinear characteristics of waves generated by submerged jets. [ABSTRACT FROM AUTHOR]

Accurately simulating the incidence of the spatially inhomogeneous multidirectional irregular waves in numerical modeling of wave propagation on coastal areas is vitally important for engineering design. In this paper, the Inhomog-Bound-EEED, Inhomog-Bound-PTPD and Inhomog-Bound-DSFD approaches are established and their capabilities for simulating the inhomogeneous incident wave boundary are verified by the coupling of Boussinesq wave model with theoretical diffraction wave model and with SWAN wave model. The incident wave information of the Boussinesq wave model is simulated by the proposed methods based on the wave information provided by the wave diffraction or SWAN model. The simulated time series and significant wave heights by the Boussinesq wave model show good agreement with the results of the theoretical diffraction wave model, which verifies the validities of the proposed Inhomog-Bound-PTPD and Inhomog-Bound-DSFD approaches. The obvious consistency of the simulated results for the analyzed significant wave heights and directional distributions between the Boussinesq wave model and the theoretical diffraction wave model verifies the effectiveness of the Inhomog-Bound-DSFD method, and the method is further applied to the numerical coupling of the Boussinesq wave model and SWAN model. The proposed three methods have good applicability to simulate the spatially inhomogeneous multidirectional irregular wave incident boundary. • Three types of inhomogeneous incident wave boundary simulation methods are established. • The Inhomog-Bound-EEED, -PTPD and -DSFD methods are described respectively. • The nonuniform incident wave information of the Boussinesq wave model is simulated. • The coupling modeling of the Boussinesq wave model with theoretical diffraction and SWAN wave model are implemented. [ABSTRACT FROM AUTHOR]

β-Ga 2 O 3 , as an emerging wide bandgap semiconductor material, has been attracting much attention in recent years. To promote the progress of β-Ga 2 O 3 in laser processing, microchannels were fabricated on the surface of β-Ga 2 O 3 using picosecond laser, and the surface morphology and internal structure of the microchannels were characterized. Rastering on a β-Ga 2 O 3 substrate created surface nanostructures including laser-induced periodic surface structures (LIPSS) at a low spatial frequency (period 861∼958 nm). These highly aligned periodic structures can be controlled by laser scanning speed. In addition, the ablation threshold of single pulse is extended to multi-pulse ablation threshold, which is more in line with the actual processing requirements. The interaction mechanism between ultrashort pulse laser and β-Ga 2 O 3 is discussed using a two-temperature model (TTM). [ABSTRACT FROM AUTHOR]

Abstract: In this paper, a numerical model based on the improved Boussinesq equations derived by Beji and Nadaoka is first developed using unstructured finite element technique. A locally rotated coordinate system is introduced to improve the treatment for the fully reflective boundaries whose orientation does not coincide with the coordinate system. The Adams–Bashforth–Moulton predictor–corrector scheme is used for time integration. Typical examples are employed to validate the numerical model. Based on the developed model, multidirectional wave propagation through a cylinder group is numerically calculated and the effects of the wave directionality on the waves in the group and the wave run-up on the cylinders are investigated. Numerical results show that the wave directionality has considerable effect on the wave run-up in the cylinder group. [Copyright &y& Elsevier]

Presently, most studies of wave height distribution on slopes are based on normal incident unidirectional waves. In this study, the wave height, crest, and trough distributions of oblique incident unidirectional and multidirectional irregular waves on a 1:15 slope were experimentally investigated. The Composite Weibull Distribution fitted the experimental data well and could be applied to predict the wave height, crest, and trough distributions for unidirectional and multidirectional waves on the slope. The shape parameter with a constant value k 2 = 3.6 in Composite Weibull Distribution proposed by Battjes and Groenendijk (2000) did not describe the actual variation of wave height distribution in the surf zone. The parameters' values in Composite Weibull Distribution were modified and the corresponding fitted formulas were proposed in this paper. The results showed that the fitting parameters' values of Composite Weibull Distribution between normal and oblique incident irregular waves, and between unidirectional and multidirectional irregular waves were slightly different. But the directional spreading had little effect on the fitting parameters' values for narrow directional spreading waves. These findings for a 1:15 slope can be referenced as a supplement to the conclusions of Battjes and Groenendijk (2000). • Wave height, crest, and trough distributions of unidirectional and multidirectional waves on slope were investigated. • The influences of incident angle and directional spreading on wave height, crest, and trough distribution were analyzed. • The parameters' values in Composite Weibull Distribution were modified and corresponding fitted formulas were proposed. • These findings for 1:15 slope can be referenced as a supplement to the conclusions of Battjes and Groenendijk (2000). [ABSTRACT FROM AUTHOR]

In a recent paper, Zhang et al. (2019) statistically analyzed the pile group effect of nine piles in a side-by-side arrangement exposed to multi-directional irregular waves. In this study, the corresponding data are further analyzed and their probabilistic distributions are examined. The Weibull distribution is used to fit the measured wave force, and the relationships between parameters A and B of the Weibull distribution are given, where it satisfactorily fitted the probability distribution of the measured wave force on the piles with the appropriate parameters. To explain the rules governing the probability distribution of the wave force, the relationships between this and the characteristics of force groupiness are studied. Variations in the parameters of the Weibull distribution and the average force coefficients are also examined using the proposed KC LD 1/3 and relative spacing (S / D). The results show that the probability distribution of the irregular wave force on piles exposed to multi-directional irregular waves is strongly dependent on the wave directionality, KC LD 1/3 numbers and relative spacing. • A probabilistic analysis of nine piles in a side-by-side arrangement exposed to multi-directional waves is carried out. • Weibull distribution could adequately fit the probability distribution of the force on the piles. • Probability distribution of wave force on piles are strongly dependent on the wave directionality. [ABSTRACT FROM AUTHOR]

A novel CFE adhesive hydrogel was constructed as a multifunctional dressing material for diabetic wound healing. The CFE adhesive hydrogels exhibited good mechanical strength (adhesive, injectable, moldable and self-healing), pH-responsive EGCG release and photothermal properties, as well as excellent antimicrobial, anti-oxidant, anti-inflammatory and angiogenic activity. Additionally, the CFE adhesive hydrogels could be detached on-demand by spraying natural organic acid. [Display omitted] • CFE adhesive hydrogels were rapidly synthesized using a one-pot method. • The structure of hydrogels consists of dual-dynamic covalent crosslinking. • CFE adhesive hydrogels showed considerable NIR/pH dual-responsive properties. • CFE adhesive hydrogels showed excellent diabetic skin wound healing effect. • CFE adhesive hydrogels display favorable on-demand detachable property. Favorable adhesion and on-demand detachment are the key characteristics for evaluating the effectiveness of diabetic wound dressings in clinical. Herein, a novel adhesive hydrogel is constructed based on dual dynamic covalent (Schiff base and borate ester bond) cross-linking among carboxymethyl chitosan (CMCS), 2-formylphenylboronic acid (2-FPBA) and epigallocatechin-3-gallate (EGCG) as a multifunctional dressing material for diabetic wound healing. The CMCS/2-FPBA/EGCG (CFE) adhesive hydrogels not only display good mechanical strengths (adhesive, injectable, moldable and self-healing), considerable pH-responsive EGCG releasing and photothermal properties, but also excellent antimicrobial, anti-oxidant, anti-inflammatory and angiogenetic activity. Interestingly, CFE adhesive hydrogels display on-demand detachable property while spraying natural organic acid (citric acid, salicylic acid, and vitamin C), which could avoid secondary injury during changing the wound dressings. Therefore, this study provides a promising and comprehensive strategy with great potential for application in the diabetic wound treatment. [ABSTRACT FROM AUTHOR]

Most studies of wave breaking on slopes to date have investigated regular waves or normal incident unidirectional waves. In this study, wave breakings of normal and oblique incident irregular waves and multidirectional irregular waves on a 1:15 slope were investigated. The breaking criteria of irregular waves based on significant wave height and individual wave height were determined. Firstly, breaker indexes calculated using significant wave heights at incipient breaking were analyzed; they were substantially lower than the breaker indexes of regular waves. The breaker index formulae of irregular waves are presented based on the referred formula of regular waves. Furthermore, the breaker indexes of oblique incident waves were larger than the breaker indexes of normal incident waves. However, wave directionality had little effect on breaker indexes under the present experimental conditions. Secondly, the breaker index (the ratio of significant wave height to water depth) in surf zone was analyzed. It increased with a decrease in relative water depth. Thirdly, information of individual waves in irregular wave trains was tracked by the wave-by-wave method. The breaker indexes derived by individual wave heights were larger than the incipient breaker indexes derived from significant wave heights. Based on previous empirical formulae, some relatively simple expressions are proposed to calculate individual breaking wave heights for unidirectional irregular waves. • Experiments on a 1:15 slope for normal and oblique incident irregular waves and multidirectional waves are performed. • The breaker indexes calculated by significant wave height at incipient wave breaking and in the surf zone are analyzed. • The breaker indexes calculated by individual wave height for normal incident irregular waves are proposed. • These results can provide reference values for other slope terrain and for verifying the corresponding numerical models. [ABSTRACT FROM AUTHOR]

Accurately reproducing multi-directional irregular waves in laboratory or numerical wave basin is crucial for in-depth study of real wave-action on marine structures. In this paper, the EEED (Equal-Energy-in-Each-Division) and PTPD (Phase-Time-Path-Difference) approaches are described, and their capability for reconstructing multi-directional irregular waves is assessed. The key difference between these two methods is the determination of the component wave directions. Theoretically and (arbitrary) numerically simulated multi-directional waves with different directional distribution width and wave steepness are reconstructed, and the latter waves are further reproduced in a numerical wave basin. The consistency between the reconstructed and the theoretical/measured waves demonstrates the approaches are acceptable. Furthermore, the variation of the quantitative error between the reconstructed and the theoretical/measured waves in the spatial domain (rr / L s) is analyzed. This variation increases with the size of rr / L s , but the errors are acceptable as long as this size is reasonable. The application ranges are evaluated based on a qualitative comparative analysis between the reconstructed waves and the theoretical/measured ones and the quantitative reconstruction error along rr / L s. The PTPD approach is generally better than EEED method. The optimum relative separation for wave gauges using the PTPD approach should be smaller than 0.12 L s. • The wave reconstruction approaches (EEED and PTPD) are assessed. • Wave reconstruction error Er increases with specified spatial domain increasing. • Directional distribution width is the important effecting factor on the accuracy. • PTPD approach is generally better than EEED approach. • The suggested optimum relative wave-gauge separations for PTPD method is ≤ 0.12 L s. [ABSTRACT FROM AUTHOR]

Cross-modal search has become a research hotspot in the recent years. In contrast to traditional cross-modal search, social network cross-modal information search is restricted by data quality for arbitrary text and low-resolution visual features. In addition, the semantic sparseness of cross-modal data from social networks results in the text and visual modalities misleading each other. In this paper, we propose a cross-modal search method for social network data that capitalizes on adversarial learning (cross-modal search with adversarial learning: CMSAL). We adopt self-attention-based neural networks to generate modality-oriented representations for further intermodal correlation learning. A search module is implemented based on adversarial learning, through which the discriminator is designed to measure the distribution of generated features from intramodal and intramodal perspectives. Experiments on real-word datasets from Sina Weibo and Wikipedia, which have similar properties to social networks, show that the proposed method outperforms the state-of-the-art cross-modal search methods. [ABSTRACT FROM AUTHOR]

With the significant development of the Internet of Vehicles (IoV), various modal data, such as image and text, are emerging, which provide data support for good vehicle networking services. In order to make full use of the cross-modal data, we need to establish a common semantic representation to achieve effective measurement and comparison of different modal data. However, due to the heterogeneous distributions of cross-modal data, there exists a semantic gap between them. Although some deep neural network (DNN) based methods have been proposed to deal with this problem, there still exist several challenges: the qualities of the modality-specific features, the structure of the DNN, and the components of the loss function. In this paper, for representing cross-modal data in IoV, we propose a common semantic representation method based on object attention and adversarial learning (OAAL). To acquire high-quality modality-specific feature, in OAAL, we design an object attention mechanism, which links the cross-modal features effectively. To further alleviate the heterogeneous semantic gap, we construct a cross-modal generative adversarial network, which contains two parts: a generative model and a discriminative model. Besides, we also design a comprehensive loss function for the generative model to produce high-quality features. With a minimax game between the two models, we can construct a shared semantic space and generate the unified representations for cross-modal data. Finally, we apply our OAAL on retrieval task, and the results of the experiments have verified its effectiveness. [ABSTRACT FROM AUTHOR]

[Display omitted] • Design and synthesis of a panel of novel cannabidiol derivatives with antibacterial activities. • 21f showed augmented antibacterial activity against MRSA with a MIC of 4 μM without cytotoxic effect in BV2 cells. • 21f could inhibit the formation of biofilms, induce excess reactive oxygen species, and reduce bacterial metabolism. • 21f could be a promising lead compound and deserves further in-depth studies. Drug-resistant bacterium infections are a severe threat to public health and novel antimicrobial agents combating drug-resistant bacteria are an unmet medical need. Although cannabidiol (CBD) has been reported to show antibacterial effects, whether its antibacterial activity against methicillin-resistant Staphylococcus aureus (MRSA) can be improved remains unclear. Herein, a series of novel CBD derivatives were designed and synthesized using various chemical approaches including amidation, Friedel-Crafts alkylation, and Negishi cross-coupling reaction for the modifications at the C-7, C-2′, C-4′, and C-6′ positions of CBD skeleton. Derivative 21f showed augmented antibacterial activity against MRSA with a minimum inhibitory concentration of 4 μM without cytotoxic effect in microglia BV2 cells. Further mechanistic studies suggested that 21f inhibited the formation of biofilms, induced excess reactive oxygen species, and reduced bacterial metabolism, which collectively led to the acceleration of bacterial death. Findings from this study expand the understanding of CBD derivatives as promising antibacterial agents, which provides useful information for the development of cannabinoid-based antibacterial agents. [ABSTRACT FROM AUTHOR]

As drug-resistant strains of Eimeria have emerged and concerns about drug residues in poultry have grown, there is renewed interest in identifying natural alternatives to control coccidiosis. Cedrol, a natural sesquiterpene alcohol, was used in this study to test anticoccidial efficacy in chicks. Both the control and treatment groups were orally challenged with 2 × 104 oocysts per chicken. Chicks administered with cedrol had reduced oocyst count, an increase in the relative weight gain rate of chicks, and a decrease in severe swelling of the cecum. Based on the above, ACI was calculated and the cedrol group reached moderate anti-coccidial activity (169.34). In chickens treated with cedrol, there were no changes in serum biochemical parameters, but oxidative stress biomarkers and cytokine levels associated with anticoccidial response were altered. These changes suggest that the administered concentration of cedrol did not have any adverse effects on the chickens while enhancing their antioxidant capacity and immunity, leading to an improved anticoccidial ability. In conclusion, this study shows that the addition of cedrol in poultry production has an anticoccidial effect and successfully improves growth performance during the growth period. [Display omitted] • Cedrol was proven to have anticoccidial effects in chickens. • The compound enhanced the antioxidant and immunity of chickens. • This study provided a candidate drug for controlling chicken coccidiosis. [ABSTRACT FROM AUTHOR]

The Heilongjiang River Basin is a vast area with significant DOM sources and composition differences. The mechanism of DOM degradation under spatial variation remains unclear. This research investigated the degradation characteristics of DOM in different watersheds of the Heilongjiang River. DOM levels were higher in midstream waters, while DOM degradation rates were higher in midstream and downstream waters. The parallel factor analysis (PARAFAC) results showed that the upstream amino acid fraction was significantly depleted, the midstream was dominated by the degradation of DOM of terrestrial origin, and the downstream humic acid fraction was decreased considerably. Gene sequencing results indicated that the upstream, middle, and downstream water bodies' microbial community composition and structure differed significantly. The network analysis results revealed microorganisms in upstream water bodies mainly utilized amino acid-like substances and small molecule humic acids. Microorganisms in the middle and lower reaches of the water column were characterized by the utilization of humic acid-like fractions. In this study, we further screened the key driving microorganisms (e.g., Flavobacterium and Lacibacter) responsible for the difference in the DOM utilization function of upstream-to-midstream and midstream-to-downstream microorganisms in the Heilongjiang River. These findings will help identify the cycling process of DOM under spatial variation and predict the succession pattern of microbial communities. [Display omitted] • The rate of DOM degradation varied among watersheds. • Photodegradation plays an important role in the degradation of DOM. • The DOM composition of different watersheds showed homology. • Differences in microbial community composition and function exist. • Key driver microorganisms were identified between different watersheds. [ABSTRACT FROM AUTHOR]

The performance of coastal vertical seawalls in extreme weather events is studied numerically, aiming to provide guidance in designing and reassessing coastal structures with vertical wall. The extreme wave run-up and the pressure on the vertical seawall are investigated extensively. A time-domain higher-order boundary element method (HOBEM) is coupled with a mixed Eulerian-Lagrangian technique as a time marching technique. Focused wave groups are generated by a piston wave-maker in the numerical wave tank using a wave focusing technique for accurately reproducing extreme sea states. An acceleration-potential scheme is used to calculate the transient wave loads. Comparisons with experimental data show that the extended numerical model is able to accurately predict extreme wave run-ups and pressures on a vertical seawall. The effects of the wave spectrum bandwidth, the wall position and the wave nonlinearity on the wave run-up and the maximum wave load on the vertical seawall are investigated by doing parametric studies. [ABSTRACT FROM AUTHOR]