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[Display omitted] • The deep learning approach is proposed to generate unit cells of point clouds for 3D lattice structures with anticipated properties. • The point clouds, surfaces, and mechanical properties of the designed 3D unit cells show high similarities to the target structures. • The applications of proposed approach are demonstrated in orthopedic implants, new hybrid unit cells, and functionally gradient structures. Lattice structures have been a hot topic recently owing to their superior mechanical properties, which are significantly influenced by the unit cell structure. By leveraging the power of deep learning, inverse design can be conducted on the unit cell structure based on the mechanical properties of its lattice structure. Assisted by deep learning, this study introduces a novel data-driven approach to design three-dimensional (3D) unit cells for lattice structures with anticipated properties. The approach can be efficiently and accurately applied to various unit cell structures. An auto-encoder is trained to extract the geometric features from unit cell point clouds. The effective mechanical properties of the lattice structures are calculated by combining the homogenization method and the finite element method. Subsequently, a mapping relationship between mechanical properties and geometric features is established through the multi-layer perceptron neural network. The models are ultimately employed to design 3D unit cells given anticipated properties of lattice structures. The results show that the mechanical properties of the generated unit cells satisfy the anticipated values. The applications of proposed method are demonstrated in orthopedic implants, new hybrid unit cells, and functionally gradient structures. Furthermore, the method can be extended to unit cell design across diverse domains. [ABSTRACT FROM AUTHOR]

• A series of Voronoi porous structures with tunable Poisson's ratio were proposed. • Mechanical properties of VP-VPS structures exhibited global strain rate sensitivity. • Deformation modes of VP-VPS structures under global strain rates were unveiled. • New type VP-VPS crash boxes had high impact energy absorption. As the inner core of crash box, the porous structure could cushion impact load through its own deformation. The aims of this study were to propose a series of Voronoi porous structures with tunable Poisson's ratio (VP-VPS) by using the periodic array of unit cells based on Voronoi-Tessellation and to develop crash boxes filled with porous structures for strong crashworthiness and high energy absorption. VP-VPS structures through the periodic arrays of unit cells were constructed according to 4 independent unit cell design factors. The quasi-static and dynamic compressive mechanical responses of VP-VPS structures prepared by selective laser melting (SLM) were studied through the combinations of mechanical test and simulation. Relationships between VP-VPS unit cell design factors and mechanical properties of structures were determined by establishing regression equations using the response surface method (RSM). Finally, the energy absorption of new crash boxes filled with VP-VPS structures was investigated through simulation. Results showed that VP-VPS structures had high load-bearing capacities and energy absorption under quasi-static and dynamic compressive conditions. Regression equations based on RSM could well predict mechanical properties of structures. The mechanical properties of VP-VPS structures were enhanced with the increase of global strain rate, which showed different deformation modes at low and high global strain rates. Compared with typical crash boxes filled with negative Poisson's ratio (NPR) inner cores, new type VP-VPS crash boxes had stronger impact resistance and higher energy absorption. This investigation provided a feasible design solution and theoretical basis for the construction and engineering application of impact resistance protective structures. [Display omitted] [ABSTRACT FROM AUTHOR]

• Orthotropic triply periodic minimal surface-based porous structure is proposed. • Structural influence on manufacturability of the scaffolds is evaluated. • Homogenization theory is used to calculate anisotropic degrees of the scaffolds. • Anisotropic mechanical and mass-transport properties of the scaffolds are analyzed. To obtain porous scaffolds with bionic anisotropic structures similar to human bone, the orthotropic triply periodic minimal surface (TPMS)-based structures were proposed in this study. The orthotropic Schoen's I-WP (AP) and orthotropic Gyroid (AG) were designed based on isotropic I-WP (IP) and isotropic Gyroid (IG). The four scaffolds with 70% porosity were fabricated by electron beam melting, and then were scanned by microcomputer tomography to evaluate their manufacturability. The anisotropic degrees of elastic properties of the scaffolds were calculated using the homogenization approach. Compression test along the three orthogonal directions was conducted on the scaffolds to analyze their mechanical properties. Computational fluid dynamics was performed to the scaffolds along the three orthotropic directions to characterize their mass transport properties. Results show that AP and AG possess irregular pores and perform well in manufacturability compared with IP and IG. Similar to human bone, AP and AG exhibit orthotropic mechanical properties and mass transport performances. Furthermore, the elastic modulus ratio of AG along the three orthogonal directions is close to the value of cancellous bone. The designed scaffolds are advantageous for their bionic mechanical and mass transport properties of human bone and can be the proper candidates in bone graft surgery. [ABSTRACT FROM AUTHOR]

In total knee arthroplasty, the optimal length and material of tibial stem remain controversial. This study aimed to evaluate influences of lengths and materials of cementless stems on tibial remodeling behaviors. Three groups of lengths were investigated (i.e., 110, 60, and 30 mm), and four materials (i.e., titanium, flexible ‘iso-elastic’ material, and two functionally graded materials [FGMs]) were selected for each group. FGM is a kind of material whose composition gradually varies in space. In this study, the compositions of two FGMs were Ti and hydroxyapatite (FGM I), and Ti and bioglass (FGM II), respectively. Tibial models were incorporated with finite element analysis to simulate bone remodeling. Distributions of bone mineral density, von Mises stress, and interface shear stress were obtained. For the length, the long stem produced more serious stress shielding and stress concentration than the short stem, but it could provide better mechanical stability. For the material, FGM I could reduce stress shielding and stress concentration and reduce the risk of loosening. Compared with the length, the material had a pronounced effect on remodeling. This study provided theoretical basis for optimal design of stem to improve service life of tibial components and to reduce pain of patients. [ABSTRACT FROM AUTHOR]

• A strategy combining hot isostatic pressing and electropolishing was proposed to enhance the fatigue resistances of TPMS-based scaffolds. • Fatigue FEA was performed to reveal the fatigue mechanisms of TPMS-based scaffolds with different topologies. • FEA based on Micro-CT images was used to analyze the effect of surface quality on local stress. • The residual stress in the fabricated and HIP'ed scaffolds was qualitatively and quantitatively evaluated. To improve the endurance limits of triply periodic minimal surface (TPMS)-based scaffolds, the post-treatment process combing hot isostatic pressing (HIP) and electropolishing (ELP) was proposed and conducted in TPMS-based scaffolds with various structures. Thus, the fatigue properties were enhanced from three aspects: changing the topological structures of TPMSs, improving surface qualities and eliminating internal defects. The stretching-dominated scaffold-new diamond (AD) and the bending-dominated scaffold-network-based gyroid (IG) were selected and their relative densities were set to 20%. These scaffolds were fabricated by electron beam melting using Ti6Al4V powders. HIP and ELP were conducted in the manufactured scaffolds. Then, compression–compression fatigue tests were performed and fatigue parameters such as fatigue life, accumulated strain rate, fatigue strength and fatigue ratio were obtained. The experimental techniques of scanning electron microscopy, microcomputer tomography, optical microscopic, X-ray diffraction and electron backscattered diffraction were carried out to characterise the surface qualities, internal defects and microstructures. The effects of topological structure and surface quality on the stress distribution on TPMS-based scaffolds under compressive loading were investigated by finite element analysis. Results show that topological structures, surface qualities and internal defects all affect the fatigue properties of TPMS-based scaffolds. Under cyclic compressive loading, the fatigue ratios of IG and AD without undergoing post-treatment are 0.11 and 0.59, respectively, while they rise to 0.26 and 0.69 after HIP and ELP. Compared with surface qualities and internal defects, topological structures influence the fatigue properties of TPMS-based scaffolds more prominently. The fatigue properties of TPMS-based scaffolds can be enhanced by the post-treatment process combing HIP and ELP, and greater improvement will be obtained for bending-dominated structures than stretching-dominated structures. Thus, manipulating the topological structures and increasing the buckling components of TPMS-based scaffolds is an effective way to obtain porous scaffolds with excellent fatigue properties under cyclic compressive loading. HIP and ELP can also be adopted to further improve their fatigue lives. The novelty of this study lies in improving the fatigue properties of TPMS-based scaffolds from the three aspects, which are changing the topology structure, improving the surface quality and reducing the internal defects, and the mechanisms of improving the fatigue properties of TPMS-based scaffolds are systematically discussed. [Display omitted] [ABSTRACT FROM AUTHOR]

The laser performance of liquid-crystal devices (LCDs) must be considered because of their applications in laser systems. The phase modulation variation mechanisms, as well as the key absorption factor under continuous-wave (CW) laser loading, remain unclear. In this study, the influence of indium tin oxide (ITO) layers on the laser tolerance of LCDs under CW laser loading was investigated. Comparing the phase modulation variations and thermal effects of passive and active LCDs, the influence of the ITO absorbing layer and the decisive role of temperature on the laser tolerance of the LCDs were confirmed. The results showed that the laser tolerance of the LCD with ITO layers was approximately one-seventh of that of the LCD without ITO layers. ITO layers have proven to be the main absorption factor for active LCDs. However, the variations in phase modulation and morphology under CW laser loading were similar for LCDs with or without ITO layers. The phase modulation variations of the LCDs increased with increasing temperature in the irradiated area. For LCDs with or without ITO, once the CW laser loading induced a similar temperature increase, their phase modulation variations were almost the same. The temperature rise of LCDs is confirmed to be an effective parameter for evaluating the phase modulation degradation of LCDs in high-power CW laser applications. The coincidence between the theoretical and experimental phase modulation variations for LCDs with or without ITO indicates that the temperature-induced refractive index change was the main reason for the LCD phase modulation variation under CW laser loading. These results clarify the basic mechanisms of the phase modulation variation of LCDs under CW laser loading and provide guidance for process optimization and application of LCDs in high-power laser systems. [ABSTRACT FROM AUTHOR]

Our aim was to compare in a prospective study the clinical effects and safety of propranolol given orally, timolol maleate applied locally, and the combination of the two, in the management of superficial infantile haemangiomas. Thirty-nine patients with superficial infantile haemangiomas were randomised into three equal groups of 13 each: the first given timolol maleate applied topically together with propranolol given orally, the second given only propranolol orally, and the third given only timolol maleate topically. Photographs were taken before, and periodically after, starting treatment. A minimum of 50% improvement was considered to be effective. The maximum duration of treatment was planned for 6 months, and the patients were followed up for 3-12 months. The overall rate of clinical effectiveness for the three groups was 11/13, 9/13, and 8/13, respectively. The two drugs together had a shorter effective response time than when they were given separately. There were no serious adverse effects. We therefore conclude that timolol maleate given topically together with propranolol given orally is safe and effective in the treatment of superficial infantile haemangiomas. Compared with simple medication, this method is more rapid, has an appreciable effect, takes a shorter time, and has fewer adverse reactions. It could be used as a first-line treatment, particularly if the lesion is potentially disfiguring or functionally threatening such as large periocular superficial haemangiomas. [ABSTRACT FROM AUTHOR]

A macro–micro–nano–multi-level study was conducted to explore age-related structural and mechanical properties of bone, as well as the effects of aging on bone properties. A total of 70 male Wistar rats were used, ranging in the ages of 1, 3, 5, 7, 9, 11, 14, 15, 16, and 17 months ( n = 7/age group). After micro-computed tomography (CT) scanning, longitudinal cortical bone specimens with a length of 5 mm were cut along the femoral shaft axis from left femur shafts for mechanical testing, and the cross-sectional areas were measured. The macro-mechanical properties obtained in mechanical testing and microarchitecture parameters measured by micro-CT were significantly correlated with the animal age (r 2 = 0.96, p < 0.001). Scanning electron microscopy was used for detecting the microarchitecture features of the fractured surfaces, which exhibited age-related plate-fibrous-mixed fibrous-plate texture, resulting in changes in macro-mechanical properties (r 2 > 0.90, p < 0.001). The mineral phase of the left femoral shaft and head was analyzed by atomic force microscopy. Longitudinal and transverse trabecular bone tissues, as well as longitudinal cortical bone tissue, were used for nanoindentation test, and the chemical composition was evaluated by quantitative chemical analyses. The correlations between mineral content and bone material properties (i.e., elastic properties of the bone tissue and size and roughness of bone mineral grains) were highly significant (r > 0.95, p < 0.001). Multi-level femur morphology, mechanical property, and mineral content were significantly correlated with the animal age. The correlations between bone mineral content and bone material morphological and mechanical properties may partly explain the increase in bone fragility with aging, which will provide a theoretical basis for the investigation of age-related bone properties in clinics. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the mechanical properties and features of bone materials at the nanoscale level in different regions of the femoral head in elderly patients with femoral neck fracture. Ten femoral heads from female patients with femoral neck fractures were extracted during surgery (five for the Aged group, aged 65–66 years; five for the Advanced aged group, aged 85–95 years). The femoral head was divided into three equal layers (anterior, central, and posterior) in the coronal view, and each layer was segmented into five regions (superior, central, inferior, medial, and lateral). Nanoindentation testing and atomic force microscopy imaging were used to study the mechanical properties and surface morphology of the specimens. No statistical differences in grain size were found between age groups, which suggested that the nanostructure of trabeculae in the femoral heads of postmenopausal women cannot be used to predict age-related bone loss and fracture risk. Mechanical properties in the longitudinal direction deteriorated more quickly than those in the transverse direction for the whole femoral head. Comparisons between layers showed a higher deterioration rate with aging in the anterior layer than in other layers. In different regions, mechanical properties of the medial and lateral regions deteriorated more quickly than those in the three other regions, and deterioration in the longitudinal direction was more serious than that in the transverse direction. The regional deterioration patterns and material properties with aging observed in this study contribute to an understanding of the age-related fracture mechanism and provide a basis for predicting age-related fracture risk and decreasing early fixation failure in the proximal femur. [ABSTRACT FROM AUTHOR]

[Display omitted] • A synthesis strategy of self-sourced silicon embedded in 2D biomass-based carbon sheets without additional additives is proposed. Utilizing the uniform dispersion of the elements of the raw material itself, the product has good uniformity. The products are not restricted by the scale of production and can be mass-produced. • As-synthesized material significantly increases the energy storage capacity, while ensuring stable cycle capacity and excellent rate capacity in the sodium ion battery. • The raw materials have a wide range of sources, large reserves, low prices, and renewable resources. And the synthesis process is simple and easy. In this research, 2D self-sourced silicon-embedded carbon sheets were prepared through pre-treatment combined with a high-temperature carbonization strategy. Through X-ray diffraction (XRD), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), specific surface area and pore size analysis, scanning electron microscope (SEM) and transmission electron microscope (TEM) and other technical means to obtain the electrode material structure and morphology. The results show that the pretreatment of the acidic system can effectively ensure the two-dimensional sheet while ensuring the precipitation of the raw material silicon. At the same time, the energy storage capacity and electrochemical performance of obtaining anode in sodium ion batteries (SIBs) were studied. The anode shows high specific capacity, excellent rate performance and stable cycle performance. At a current density of 100 mA.g−1, a specific capacity of 180mAh.g−1 was obtained. After 1000 cycles, it still has a coulomb efficiency of 99.7% and a capacity retention rate of 94.6%. Furthermore, the rapid reaction kinetics capability of this material was analyzed by calculating the proportion of pseudo-capacitance contribution in the system and the sodium ion diffusion coefficient. Its stable energy storage capacity and cycle stability make it a promising candidate for sodium ion batteries. [ABSTRACT FROM AUTHOR]

• A porous structure with high porosity and high mechanical properties is designed. • A strategy of controlling the topology structure of TPMS-based scaffold is proposed. • A parameter of no obstacle ratio is defined to describe the permeability of scaffold. • Increasing no obstacle ratio is helpful to improve the surface quality of scaffold. A strategy of controlling the topology structure of triply periodic minimal surface (TPMS)-based scaffolds (CTTS) was proposed in this study to cater to the mechanical and biological requirements. Two new types of TPMS-based scaffolds called AD and AG were designed on the basis of diamond (ID) and gyroid (IG). The topology structures of ID and IG were changed by manipulating the trigonometric functions in the expressions. AD and AG retained the advantageous structural characteristics of ID and IG, such as high wall surface area and good connectivity. However, they differed in terms of pore shape and size. The gradient density ID (FD) and the gradient density IG (FG) were designed for comparison. The porosities of ID, IG, FD, FG, AD, and AG were set to 60, 70, and 80%. Compressive simulations and computational fluid dynamics simulations were conducted for the designed scaffolds. AD with 80% porosity (AD80) and FD with 80% porosity (FD80) were manufactured through electron beam melting. Their morphological features were characterized through microcomputer tomography scanning and scanning electron microscopy. Compression and fall head tests of AD80 and FD80 were performed. In combination with the numerical results, the geometrical parameters, manufacturing accuracies, mechanical properties, permeability, and flow behavior of each scaffold were systematically analyzed. Results show that with the same porosity, the manufacturing accuracies and the permeability of AD and AG are higher than ID, IG, FD, and FG. The mechanical properties of AD are higher than other scaffolds. Although the wall surface area of AD is smaller than ID and FD, it is still larger than IG and FG, which can provide sufficient space for cell adhesion. AD is an appropriate candidate for solving the contradiction between sufficient mechanical properties and high permeability and exhibits excellent biological property. [Display omitted] [ABSTRACT FROM AUTHOR]

Objective To develop a high-throughput screening assay for Farnesoid X receptor (FXR) agonists based on mammalian one-hybrid system (a chimera receptor gene system) for the purpose of identifying new lead compounds for dyslipidaemia drug from the chemical library. Methods cDNA encoding the human FXR ligand binding domain (LBD) was amplified by RT-PCR from a human liver total mRNA and fused to the DNA binding domain (DBD) of yeast GAL4 of pBIND to construct a GAL4-FXR (LBD) chimera expression plasmid. Five copies .of the GAL4 DNA binding site were synthesized and inserted into upstream of the SV40 promoter of pGL3-promoter vector to construct a reporter plasmid pG5-SV40 Luc. The assay was developed by transient co-transfection with pG5-SV40 Luc reporter plasmid and pBIND-FXR-LBD (189-472) chimera expression plasmid. Results After optimization, CDCA, a FXR natural agonist, could induce expression of the luciferase gene in a dose-dependent manner, and had a signal/noise ratio of 10 and Z′ factor value of 0.65. Conclusion A stable and sensitive cell-based high-throughput screening model can be used in high-throughput screening for FXR agonists from the synthetic and natural compound library. [ABSTRACT FROM AUTHOR]

Poor bone quality induced by non-enzymatic glycation (NEG) of bone tissue in patients with type 2 diabetes mellitus (T2DM) is regarded as the major factor of bone fragility and affecting bone mechanical properties. A comprehensive and systemic mechanical investigation for evaluating the effect of NEG on bone was still lacking. In order to provide additional information for the bone quality of T2DM, the effects of NEG on mechanical properties of cortical bone were investigated in terms of elastoplasticity, fracture toughness and viscoelasticity. All samples of cortical bone, including the samples of strength test (n = 20), fracture toughness test (n = 40, quasi-static and fall-like conditions with displacement rates of 10−3 mm/s and 10 mm/s, respectively) and stress relaxation test (n = 20), were harvested from bovine tibiae. The samples of each test were equally divided into incubated-control group and ribose-incubated group. All mechanical tests were performed after incubating all samples for 15 days. Post-yield strain (p = 0.014), post-yield energy (p < 0.0001) and damage fraction (p = 0.040) of ribose-incubated group were significantly lower than those of incubated-control group, but secant modulus (p = 0.029) of ribose-incubated group was significantly higher than that of incubated-control group. In quasi-static condition, the plastic contribution J pl of fracture toughness (p = 0.043) of ribose-incubated group was significantly lower than that of incubated-control group. In fall-like condition, there were no differences in J pl , elastic contribution J el and J- integral in both two groups. The quasi-static J el (p < 0.0001, p < 0.0001) of incubated-control and ribose-incubated groups and J- integral (p = 0.007) of incubated-control group were all significantly higher than those of fall-like condition. In stress relaxation test, initial modulus E 0 (p = 0.040) and equilibrium modulus (p = 0.029) of ribose-incubated group were significantly higher than those of incubated-control group. Reductions of relaxation modulus, which were the differences between two adjacent time points within 700 s–3000 s for ribose-incubated group, were significantly lower than those of incubated-control group. NEG could decrease the post-yield properties and quasi-static facture toughness of cortical bone, especially the plastic contribution of quasi-static fracture toughness. It could also decrease the viscoelasticity of cortical bone. The present study confirmed the negative effects of NEG on the mechanical properties of cortical bone in terms of elastoplasticity, fracture toughness and viscoelasticity, but NEG had no significant effect on the fracture toughness of cortical bone at fall-like loading. These results provided more evidence for increased fragility of cortical bone in patients with T2DM. [Display omitted] • NEG could decrease the post-yield properties and damage fraction of cortical bone. • NEG could reduce plastic contribution of J -integral of cortical bone under quasi-static situation. • Under fall-like situation, NEG had no significant effect on J -integral of cortical bone. • NEG could also decrease the viscoelasticity of cortical bone. [ABSTRACT FROM AUTHOR]

Abstract: Proximal femoral nail antirotation (PFNA) device is an intramedullary nail system designing for the treatment of trochanteric fractures. It is composed of a helical neck blade, a nail and a distal locking bolt. There were some reports of femoral shaft fractures even after the fractures were healed. The stress shielding effects of the PFNA device made of stiff titanium alloy on the bone-remodeling behavior of the host femur and the uneven distribution of interface shear stress may contribute to this complication. Recently, a new class of composite called functionally graded material (FGM) was developed, that consisted a gradual pattern of material composition and/or microstructures, and was introduced in dental implant and cementless hip stem. Accordingly, in this paper, we hypothesized that FGM might be used as the material of the nail in PFNA device with the material composition of the nail gradually shifting from more stiff at the proximal side of the femur to more flexible ‘iso-elastic’ towards the distal side. This hypothesis can be evaluated from the long-term remodeling behavior of host femur and the stress distributions in the PFNA device and bone. [Copyright &y& Elsevier]

• Gold-plated nano-silver specimens were tested under shear loading. • A unified viscoplastic constitutive model is developed. • A variable is incorporated into the drag stress to indicate damage. Compared with most of the traditional solder materials, sintered nano-silver shows better high-temperature service performance and is expected to replace the traditional packaging materials in the next-generation of electronic devices. However, there exist substantial voids inside the sintered nano-silver layer after sintering, and the conventional continuum damage mechanics has certain limitation to describe the shear stress-strain relationship of sintered nano-silver materials. To analyze the void evolution and microstructure of sintered nano-silver, gold-plated sintered nano-silver specimens were tested under shear loading at different temperatures. A unified viscoplastic constitutive model is proposed to describe the properties of sintered nano-silver specimen under shear loading, in which the viscous overstress is replaced by the potential function of Gurson-Tvergaard-Needleman model and the effects of void on the yield surface of viscoplastic material is considered. To describe the influence of void evolution to the deterioration of mechanics properties at high temperatures, a damage variable is incorporated into the drag strength to indicate the damage mechanism with respect to the softening of sintered nano-silver material. The numerical predictions are compared with the experimental data, which shows that the developed model can describe the shear constitutive behavior of sintered nano-silver specimen with reasonable accuracy. [ABSTRACT FROM AUTHOR]

• Mechanical vibration improves the mechanical properties of lumbar vertebra in normal rats. • Mechanical vibration before ovariectomy improves the viscoelasticity of fibrous ring. • Mechanical vibration before ovariectomy prevents the degeneration of lumbar disc. • Mechanical vibration after ovariectomy improves the mechanical properties of vertebral body. The current study aimed to investigate the effects of whole-body vibration (WBV) before and after ovariectomy on lumbar vertebrae, and to observe whether the positive effects of WBV before and after ovariectomy on lumbar vertebrae in rats could be maintained after vibration stopped. Three-month-old female rats were divided into four groups (n = 45/group): control (CON), ovariectomy (OVA), WBV before ovariectomy (WBV-BO), and WBV after ovariectomy (WBV-AO) groups. For 1-8 weeks, WBV-BO group was subjected to vertical WBV. At the 9th week, the rats in WBV-BO, WBV-AO, and OVA groups were ovariectomized. During 11-18 weeks, WBV-AO group was subjected to vibration. For 19-26 weeks, no intervention was done for rats. The lumbar vertebrae were examined by Micro-CT, compressive test, creep test, and microindentation test. At the 8th week, the displacement of the L1-L2 annulus fibrosus in WBV-BO group was 18% smaller compared with CON group (p <0.05). At the 18th week, the elastic modulus of the L5 vertebral body in WBV-BO and WBV-AO groups was 53% and 57% higher than that in CON group, respectively (p <0.05); the displacement of the L1-L2 annulus fibrosus in WBV-BO group was 25% smaller than those in the other groups (p <0.05). At the 26th week, there was no significant difference in the displacement of the L1-L2 annulus fibrosus between WBV-BO group and other groups (p >0.05); the elastic modulus of the L5 vertebral body had no significant difference between WBV-AO group and CON group (p >0.05). Our results demonstrated that WBV before ovariectomy effectively prevented disc degeneration with significant effects up to 8 weeks after ovariectomy. The vertebral mechanical properties could be significantly improved by WBV after ovariectomy, but the residual effect did not maintain after WBV stopped. [ABSTRACT FROM AUTHOR]

• We investigated the effect of preoperative DEX on intracerebral hemorrhage (ICH) • DEX reduced the damage induced by ferroptosis after ICH in mice. • DEX alleviated iron deposition and oxidative stress caused by ferroptosis. • DEX could be useful to reduce ICH-related damage. Intracerebral hemorrhage (ICH) is a devastating condition with significant morbidity and mortality for which few effective treatments are clinically available. After ICH, iron overload within the perihaematomal region can induce lethal reactive oxygen species (ROS) production and lipid peroxidation, which contribute to secondary brain injury. An iron-dependent form of non-apoptotic cell death known as ferroptosis was recently identified. Ferroptosis plays an important role in ICH pathology. It is characterized by an accumulation of iron-induced lipid ROS, which leads to intracellular oxidative stress. Dexmedetomidine (DEX), an α2-adrenergic agonist, is widely used for anesthesia, pain control, and intensive care unit sedation. DEX has numerous beneficial activities, including anti-inflammatory, anti-oxidative, and anti-cell death activities. Here, we established a mouse model of ICH using collagenase VII and evaluated the effect of DEX in preventing ICH-induced brain injury. Our study showed that administering DEX reduced the damage induced by ferroptosis after ICH by regulating iron metabolism, amino acid metabolism and lipid peroxidation processes. [ABSTRACT FROM AUTHOR]

• Tibia axial loading model was used to study the bone adaptive response. • Low-level strain did not stimulate osteogenic response, regardless of time. • Mid-level strain can improve bone quality by prolonging experiment time. • High-level strain can significantly stimulate osteogenic response in a short time. • It provides a theoretical basis for further study of improving human bone quality. The osteogenic response of bone to compressive load is affected by peak strain and duration of experiment, however, combined effect of peak load and duration of experiment on the rat tibia axial loading model remains unclear. In this study, rat tibia axial loading models with different levels of peak strains and durations of experiments were established (peak loads: 10 N, 20 N and 40 N, experimental duration: 2 weeks and 4 weeks). Microcomputer tomography scanning (Micro-CT), compression mechanical test and bone tissue alkaline phosphatase (ALP) and tartrate-resistant acid phosphatase (TRAP) staining were used to investigate the effects of cyclic loading with different levels of peak strains and durations of experiments on osteogenic response of tibia in adult female Sprague-Dawley (SD) rats. This experiment demonstrates that high-level strain can significantly stimulate the osteogenic response of cancellous and cortical bones in a short period of time. However, under mid-level strain, prolonging the experiment time can significantly improve the microsturcture and macromechanical properties of bone, increase the number of osteoblasts, and achieve the goal of improving bone quality. In this study, two loading schemes of mid-level-long-term and high-level-short-term were analyzed, and the mechanical response of the tibia under two different loading schemes was investigated. It provided a theoretical basis for further promoting the study of improving human bone quality and preventing aging-related bone diseases through mechanical stimulation. [ABSTRACT FROM AUTHOR]

In order to improve the degradation resistance of sisal fibers in the alkaline cement matrix and enhance the fiber-matrix interface adhesion, silane treatment on fiber was studied. Four kinds of commonly used silane coupling agents were selected to modify the sisal fibers via the simple dip-coating method. Contact angle, water retention, and semi-immersion tests were performed on the sisal fibers to determine the influence of silane treatment on their hydrophilicity and barrier property. The interfacial bonding between the sisal fibers and cement matrix was studied by a self-designed fiber pull-out test. Furthermore, the degradation of sisal fibers embedded in cement matrix and sisal fiber reinforced cementitious composites (SFRCC) was evaluated based on the changes of mechanical properties with accelerated aging. The results indicate that silane treatment is an efficient approach to mitigate the degradation of SFRCC. • Silane treatment generates a hydrophobic fiber with a higher water retention value. • Development of an original pull-out test suitable for flexible fiber. • Composites with silane treated sisal fibers showed mitigated degradation after aging. [ABSTRACT FROM AUTHOR]

Abstract Sea surface temperatures (SSTs) strongly influence atmospheric circulation and the Earth's climate, which in turn significantly affects vegetation productivity. Most of the previous studies on the subject have focused on links between the El Niño-Southern Oscillation (ENSO) and vegetation productivity, but few studies have addressed the effects of West Pacific Warm Pool (WPWP) on that although the early stages of the ENSO phenomenon may first develop there. In this paper, we use the mean SST values in the WPWP to construct a climate index, known as the WPWP index (WPI), and study the impacts of the WPWP on global vegetation productivity. We provide evidence for a robust link among the alternating warm and cool WPI pattern, terrestrial vegetation productivity and carbon balance. The analysis is based on both satellite observations and model simulations. The results of this study show that the warm and cool WPWP phases have inverse effects on land surface temperature and precipitation. A warm (cool) WPWP is associated with a warmer (cooler) climate on global land surfaces as well as a drier (wetter) climate in southern hemisphere, and hence enhances (suppresses) vegetation productivity in the latitudes of approximately 10–70°N and suppresses (enhances) vegetation growth in the latitudes of approximately 10–30°S. The underlying mechanism is also discussed. The WPI serves as a meaningful climate index for studying the ocean-vegetation teleconnections. Graphical abstract Unlabelled Image Highlights • WPWP SST is associated with global vegetation productivity. • A warm (cool) WPWP promotes (suppresses) vegetation growth in the north of 70°N. • A warm (cool) WPWP suppresses (enhances) vegetation growth in 10–30°S. • WPI serves as a useful climate index for studying ocean-vegetation teleconnections. [ABSTRACT FROM AUTHOR]

19 compounds, including seven previously undescribed alkaloids ((−)-macleayin K (1), (+)-macleayin K (2), macleayin M (3), macleayin N (4), macleayin L (5), macleayin O (6), oxohydrastinine A (7), one new natural product (8), and 11 known compounds, were isolated from the fruit pods of Macleaya microcarpa. Their structures were defined based on NMR, HRESIMS, and electronic circular dichroism (ECD) data. A network pharmacology approach combined with molecular docking and in vitro validation was performed to determine the bioactivity, key targets of the 19 compounds against breast cancer (BC) and cervical cancer (CC). EGFR and PIK3CA could become potential therapeutic targets based a network pharmacology. Moreover, molecular docking suggested that the 19 compounds combined well with EGFR and PIK3CA, respectively. Their cytotoxicity of selected compounds was tested against the MCF-7 and HeLa cells, and the preliminary structure-activity relationship is discussed. Compounds 1 (IC 50 : 6.00 μM) and 2 (IC 50 : 6.82 μM) exhibited strong inhibitory activity against the HeLa cells and are worthy of further study. [Display omitted] • 19 alkaloids were isolated from the fruit pods of Macleaya microcarpa. • 1 – 4 belong to the new heterozygotic dimer with dihydrobenzophenanthridine skeleton linked to a phenylethyl or benzyl. • The absolute configurations of 1 and 2 were clarified by ECD calculations. • PIK3CA and EGFR may be the key targets of Macleaya microcarpa against breast cancer and cervical cancer. • Six compounds have potent cytotoxicity against MCF-7 and HeLa cells, IC 50 < 10 μM. [ABSTRACT FROM AUTHOR]

Steroid-associated osteonecrosis (SAON) may lead to joint collapse and subsequent joint replacement. Poly lactic-co-glycolic acid/tricalcium phosphate (P/T) scaffold providing sustained release of icaritin (a metabolite of Epimedium-derived flavonoids) was investigated as a bone defect filler after surgical core-decompression (CD) to prevent femoral head collapse in a bipedal SAON animal model using emu (a large flightless bird). The underlying mechanism on SAON was evaluated using a well-established quadrupedal rabbit model. Fifteen emus were established with SAON, and CD was performed along the femoral neck for the efficacy study. In this CD bone defect, a P/T scaffold with icaritin (P/T/I group) or without icaritin (P/T group) was implanted while no scaffold implantation was used as a control. For the mechanistic study in rabbits, the effects of icaritin and composite scaffolds on bone mesenchymal stem cells (BMSCs) recruitment, osteogenesis, and anti-adipogenesis were evaluated. Our efficacy study showed that P/T/I group had the significantly lowest incidence of femoral head collapse, better preserved cartilage and mechanical properties supported by more new bone formation within the bone tunnel. For the mechanistic study, our in vitro tests suggested that icaritin enhanced the expression of osteogenesis related genes COL1α, osteocalcin, RUNX2, and BMP-2 while inhibited adipogenesis related genes C/EBP-ß, PPAR-γ, and aP2 of rabbit BMSCs. Both P/T and P/T/I scaffolds were demonstrated to recruit BMSCs both in vitro and in vivo but a higher expression of migration related gene VCAM1 was only found in P/T/I group in vitro . In conclusion, both efficacy and mechanistic studies show the potential of a bioactive composite porous P/T scaffold incorporating icaritin to enhance bone defect repair after surgical CD and prevent femoral head collapse in a bipedal SAON emu model. [ABSTRACT FROM AUTHOR]