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Obesity is a high-risk factor in the development of Endometrial Cancer (EC). Our previous study observed that miR-548ag was significantly overexpressed in the sera of obese individuals. Here, we report the function of miR-548ag and its mechanism in promoting the obesity-related progression of EC. The content of miR-548ag was increased in the serum of obese EC individuals. Bioinformatics analysis indicated that the survival rate of EC patients with a higher expression of miR-548ag was significantly reduced. The Mps One Binder Kinase Activator 1B (MOB1B, the core member of the Hippo signaling pathway) is a direct target gene of miR-548ag, which is inversely correlated with the expression of miR-548ag. The overexpression of miR-548ag enhances the proliferation, invasion, and migration, and inhibits apoptosis by downregulating the expression of MOB1B, leading to the deactivation of the Hippo pathway in EC cell lines and contributing to tumor progression in vivo. Our study has established that miR-548ag functions as an oncogene by suppressing MOB1B in the development of obesity-related EC.

The switched inertance hydraulic converter is a sub-domain of digital hydraulics which relies on digital switching to adjust pressure or flow instead of the dissipation of power by throttling, providing an energy-efficient alternative to conventional proportional or servo valve-controlled systems. The high-speed switching valve is a key component to realise the digital switching and its switching characteristics has significant effects on the performance of switched inertance hydraulic converters. In this article, the switching characteristics of a high-speed rotary valve are investigated. The switching orifice area of the valve is calculated based on the movement of the valve components with a consideration of the design of the valve body and leakage. This is validated using the computational fluid dynamics model and in experiments. The valve is theoretically modelled considering the switching orifice, leakage, transition throttling and compressibility effect, and the results are validated by computational fluid dynamics and experimental tests. The valve is able to deliver a flow rate of 40 L/min at a pressure drop of 10 bar and switch at the maximum frequency of 317 Hz, with a switching transition time of about 1 ms, which shows promising performance for the use in digital hydraulics. The theoretical and computational fluid dynamics models can assist the design and optimisation of digital high-speed rotary valves, which can be very useful for understanding, analysing and optimising the characteristics and performance of switched inertance hydraulic converters in digital hydraulics.

Dual-emitting manganese ion doped LaM1-xAl11-yO19 (M = Mg, Zn) phosphors were prepared by substituting Zn2+/Mg2+ with Mn2+ and replacing Al3+ with Mn4+. The LaM1-xAl11-yO19:xMn2+,yMn4+ phosphors show a narrow green emission band of the Mn2+ ions at 514 nm and a red emission band of the Mn4+ ions at 677 nm. In addition, the thermal stability of luminescence shows that the response of Mn2+ and Mn4+ to the temperature is obviously different in LaMAl11O19, implying the potential of the prepared phosphors as optical thermometers. The decay lifetime of Mn4+ was changed with temperature due to the different fluorescence intensity ratios of Mn2+ and Mn4+, and a dual-mode optical temperature-sensing mechanism was studied in the temperature range of -50-200 °C. The maximum relative sensitivities (Sr) are calculated as 3.22 and 3.13% K-1, respectively. The unique optical thermometric features demonstrate the application potential of LaMAl11O19:Mn2+,Mn4+ in optical thermometry.

Obesity is considered an important risk factor for many metabolic disorders, especially type 2 diabetes mellitus, and microRNAs (miRNAs) play a vital role in the development of type 2 diabetes mellitus. Therefore, we conducted this study to investigate the role of miR-4431 in the obesity-associated pathobiology of type 2 diabetes mellitus.Subjects were divided into normal control (n = 36), obese (n = 36), and type 2 diabetes mellitus (n = 12) groups, and serum miR-4431 levels were analyzed. Adenovirus-vectored miR-4431 mimic or sponge was intraperitoneally injected into the normal diet group and the high-fat diet group (HFD) mice to investigate glucose tolerance, insulin sensitivity, and lipid levels. The downstream target genes of miR-4431 were predicted using bioinformatics, and they were verified in vitro.Serum miR-4431 levels were significantly high in obese and type 2 diabetes mellitus individuals, and positively correlated with the body mass index and fasting plasma glucose levels. In HFD mice, miR-4431 levels in the serum, white adipose tissue, and liver were significantly increased. Moreover, miR-4431 impaired glucose tolerance, insulin sensitivity, and lipid metabolism in mice. Bioinformatic prediction suggested that TRIP10 and PRKD1 could be the downstream target genes of miR-4431. The HFD mice showed a remarkable reduction in the mRNA levels of TRIP10 and PRKD1 in the liver, which were countered by blocking miR-4431. In HepG2 and L02 cells, miR-4431 could downregulate TRIP10 and PRKD1 while blocking glucose uptake. The luciferase reporter assay showed that miR-4431 could bind TRIP10 and PRKD1 3'-UTR.miR-4431 targets TRIP10/PRKD1 and impairs glucose metabolism.

Switched inertance hydraulic converters (SIHC) are new digital hydraulic devices which provide an alternative to conventional proportional or servo valve-controlled systems in hydraulic fluid power. SIHCs can adjust and control flow and pressure by means of using digital control signals that do not rely on throttling the flow and dissipation of power, and provide hydraulic systems with high-energy efficiency, good controllability, and insensitivity to contamination. A flow booster is one configuration of SIHCs which can deliver more flow than the supply flow. In this article, the loading effects of SIHCs are investigated by applying a time-varying load on the flow booster. A control system consisting of a PI controller and a switching frequency optimizer was designed to operate a flow booster at its optimal switching frequencies and switching ratios to maximize system efficiency when the load varies. Simulated results showed that the flow booster with the proposed controller has very good dynamic response and can be operated at an average efficiency of 70% with a time-varying load. Compared with only using a PI controller, the proposed controller can improve the overall efficiency by up to 20%. As time-varying loading conditions are commonly found in hydraulic applications, this work constitutes an important contribution to the design and development of high-efficiency SIHCs.

Dual-emitting manganese ion doped LaM

Materials that are capable of actuation in response to a variety of external stimuli are of significant interest for applications in sensors, soft robotics, and biomedical devices. Here, we present a class of actuators using composites based on a polymer of intrinsic microporosity (PIM). By adding an activated carbon (AX21) filler to a PIM, the composite exhibits repeatable actuation upon solvent evaporation and wetting and it is possible to achieve highly controlled three-dimensional actuation. Curled composite actuators are shown to open upon exposure to a solvent and close as a result of solvent evaporation. The degree of curling and actuation is controlled by adjusting the amount of filler and evaporation rate of the solvent casting process, while the actuation speed is controlled by adjusting the type of solvent. The range of forces and actuation speed produced by the composite is demonstrated using acetone, ethanol, and dimethyl sulfoxide as the solvent. The maximum contractile stress produced upon solvent desorption in the pure PIM polymer reached 12 MPa, with an ultimate force over 20 000 times the weight of a sample. This form of the composite actuator is insensitive to humidity and water, which makes it applicable in an aqueous environment, and can survive a wide range of temperatures. These characteristics make it a promising actuator for the diverse range of operating conditions in robotic and medical applications. The mechanism of actuation is discussed, which is based on the asymmetric distribution of the carbon filler particles that leads to a bilayer structure and the individual layers expand and contract differently in response to solvent wetting and evaporation, respectively. Finally, we demonstrate the application of the actuator as a potential drug delivery vehicle, with capacity for encapsulating two kinds of drugs and reduced drug leakage in comparison to existing technologies.

Fluid-borne noise (FBN) is a major contributor to structure-borne noise (SBN) and air-borne noise (ABN) in hydraulic fluid power systems and could lead to increased fatigue in system components. FBN is caused by the unsteady flow generated by pumps and motors and propagates through the system resulting in SBN and ABN. New hydraulic technologies such as digital switched hydraulic converters are also barriered by the unavoidable FBN. This article reports on a novel integrated FBN attenuation approach, which employs a hybrid control system by integrating an active feedforward noise attenuator with passive tuned flexible hoses. The active system which consists of adaptive notch filters using a variable step-size filtered-X Least Mean Squares algorithm is used to control a newly designed high-force high-bandwidth piezo-electric actuator in order to attenuate the dominant narrowband pressure ripples. The passive hose is tuned in the frequency domain and used to cancel the high-frequency pressure ripples. A time-domain hose model considering coupling of longitudinal wall and fluid waves was used to model the flexible hose in the integrated control system. Very good FBN cancelation was achieved by using the proposed integrated control approach both in simulation and experiments. It can be concluded that the active attenuator with passive flexible hoses can form an effective, cost-efficient and practical solution for FBN attenuation. The problem of high noise levels generated by hydraulically powered machines has risen significantly in awareness within industry and amongst the general public, and this work constitutes an important contribution to the sustainable development of low noise hydraulic fluid power machines.

Obesity-induced abnormal bone marrow microenvironment is an important risk factor for bone metastasis of prostate cancer (PCa). This study was intended to investigate whether obesity-induced elevated palmitic acid (PA), the most abundant free fatty acids (FFAs), increased CCL2 through GPRs/KLF7 pathway in bone marrow adipocytes(BMA) to promote the growth and metastasis of PCa. In BALB/c nude mice, we found that the distribution of BMA in the bone marrow cavity of high fatty diet(HFD) mice were significantly higher than normal diet(ND) mice. More importantly, HFD-induced obesity promotes the KLF7/CCL2 expression of BMA and PCa cells growth in bone marrow cavity. In vitro, conditioned medium with elevated CCL2 obtained from BMA incubated with PA (CM-BMA-PA) was used to deal with PCa cell lines, and a significant increase in the proliferation, invasion, and migration ability was found in PC3 cells. KLF7 could strikingly increase the CCL2 expression and release levels of BMA. Moreover, GPR40/120 involved in PA-induced high KLF7/CCL2 levels of BMA to promote malignant progression of PC3 cells. In conclusion, PA-activated GPRs/KLF7/CCL2 pathway of BMA promotes the growth and metastasis of prostate cancer. Funding: This research was funded by the Natural Science Foundation of China (grant number 81760518), Xinjiang Production and Construction Corps Key Areas Innovation Team Project (grant number 2018CB002), the Scientific and Technological Research Project of Xinjiang Production and Construction Corps (grant number 2018AB018, 2021AB028), and Projects of Shihezi University (grant number ZZZC202017A, ZZZC201817A, GJHZ201703). Declaration of Interest: None to declare. Ethical Approval: All experiments involving mice were performed in accordance with the protocol approved by the Medical Ethics Committee at First Affiliated Hospital, Shihezi University School of Medicine (reference number: A2017-115-01).

Summary The triboelectric nanogenerator (TENG) and piezoelectric nanogenerator (PENG) are two recently developed technologies for effective harvesting of ambient mechanical energy for the creation of self-powered systems. The advantages of TENGs and PENGs which include large open-circuit output voltage, low cost, ease of fabrication, and high conversion efficiency enable their application as new flexible sensors, wearable devices, soft robotics, and machines. This perspective provides an overview of the current state of the art in triboelectric and piezoelectric devices that are used as self-powered sensors and energy harvesters for soft robots and machines; hybrid approaches that combine the advantages of both mechanisms are also discussed. To improve system performance and efficiency, the potential of providing self-powered soft systems with a degree of multifunctionality is investigated. This includes optical sensing, transparency, self-healing, water resistance, photo-luminescence, or an ability to operate in hostile environments such as low temperature, high humidity, or high strain/stretch. Finally, areas for future research directions are identified., Devices; Energy Systems; Nanostructure; Nanotechnology

The nickel molybdate (NiMoO4) flakes were synthesized by a hydrothermal method. The scanning electron microscopy (SEM) images show that NiMoO4 holds an irregular flake structure. The energy dispersive spectrometer (EDS) results indicate that the O, Ni and Mo elements are uniformly distributed of NiMoO4. Then an appropriate amount of NiMoO4 was dispersed in methyl methacrylate (MMA), and polymerized at 75 ℃ for 45–60 min to obtain NiMoO4/PMMA organic glasses. The nonlinear absorption (NLA) properties were investigated by an open-aperture (OA) Z-scan technique. The NiMoO4/PMMA organic glasses exhibit a typical saturable absorption (SA) effect at the radiation wavelength of 532 nm. The mechanism of SA effect is related to the unique flake structure of NiMoO4, the band gap (Eg) of NiMoO4 and the thermo-optic effect. The results indicate that NiMoO4 flakes can be widely applied in Q-switched and mode-locked lasers.

Soft robots and devices exploit deformable materials that are capable of changes in shape to allow conformable physical contact for controlled manipulation. While the use of embedded sensors in soft actuation systems is gaining increasing interest, there are limited examples where the body of the actuator or robot is able to act as the sensing element. In addition, the conventional feedforward control method is widely used for the design of a controller, resulting in imprecise position control from a sensory input. In this work, we fabricate a soft self-sensing finger actuator using flexible carbon fibre-based piezoresistive composites to achieve an inherent sensing functionality and design a dual-closed-loop control system for precise actuator position control. The resistance change of the actuator body was used to monitor deformation and fed back to the motion controller. The experimental and simulated results demonstrated the effectiveness, robustness and good controllability of the soft finger actuator. Our work explores the emerging influence of inherently piezoresistive soft actuators to address the challenges of self-sensing, actuation and control, which can benefit the design of next-generation soft robots.

Soft robots and devices exploit highly deformable materials that are capable of changes in shape to allow conformable physical contact for controlled manipulation. While soft robots are resilient to mechanical impact, they are susceptible to mechanical damage, such as tears and punctures. The development of self‐healing materials and actuators continues to attract increasing interest, in particular, with respect to integrating self‐healing polymers to create bioinspired soft self‐healing devices. Herein, a novel piezoelectric‐driven self‐healing leaf‐motion mimic actuator is designed by combining a thermoplastic methyl thioglycolate–modified styrene–butadiene–styrene (MGSBS) elastomer with a piezoelectric macrofiber composite (MFC) for self‐sensing applications. This article is the first demonstration of a self‐sensing and self‐healing actuator‐sensor system, which is driven by a piezoelectric actuator and can mimic leaf motion. The leaf‐motion actuator combines built‐in dynamic sensing and room‐temperature self‐healing capabilities to restore macroscale cutting damage with an intrinsically high bandwidth of up to 10 kHz. The feasibility and potential of the new actuator for use in complex soft autonomous systems are demonstrated. These new results help to address the emerging influence of self‐healing soft actuators and the challenges of sensing, actuation, and damage resistance in soft robotics.\ud \ud

New materials and technologies in sensing and actuation have led to the development of soft actuators and robots for biomedical systems, assistive devices, exploration and rescue. The use of integrated actuation-sensing materials in such systems is gaining interest, but there are few examples where the body of the actuator or soft robot acts as the sensing element. The development of smart soft actuators that have inherent sensing capabilities can provide advantages of high sensitivity, ease of manufacture and cost efficiency, without impairing actuator dynamics. To achieve this goal, we have prepared soft actuators using piezoresistive composites based on a silicone matrix impregnated with short conductive carbon fibres. The optimum carbon fibre volume fraction to achieve a frequency independent conductivity and piezoresistive response was determined, with in situ mechanical and electrical testing to quantify the piezoresistive properties. The frequency dependent electrical properties and sensitivity of the composites with deformation was explained on the basis of a microstructural resistor-capacitor network model. The piezoresistive composites were used to successfully manufacture a pneumatic soft finger actuator where the resistance change of the actuator body was able to monitor deformation with applied pressure. The creation of soft actuators with an inherent sensing capability is a promising approach for control and operation of future soft robots.

Digital hydraulics is a new technology providing an alternative to conventional proportional or servovalve-controlled systems in the area of fluid power. Digital hydraulic applications, such as digital pumps, digital valves and actuators, switched inertance hydraulic converters (SIHCs) and digital hydraulic power management systems, promise high-energy efficiency and less contamination sensitivity. Research on digital hydraulics is driven by the need for highly energy efficient hydraulic machines but is relatively immature compared to other energy-saving technologies. This review introduces the development of SIHCs particularly focusing on the work being undertaken in the last 15 years and evaluates the device configurations, performance and control strategies that are found in current SIHC research. Various designs for high-speed switching valves are presented, and their advantages and limitations are compared and discussed. Current limitations of SIHCs are discussed and suggestions for the future development of SIHCs are made.

The noise in hydraulic machines presents itself as fluid-borne noise (FBN), structure-borne noise (SBN) and air-borne noise (ABN). FBN is caused by the unsteady flow produced by pumps and motors or the operation of digital hydraulics, and propagates through the system causing SBN, which in turn causes ABN. This article reports on a novel integrated FBN attenuation approach, which employs a hybrid control system by integrating an active feedforward noise attenuator with passive tuned flexible hoses. The passive hoses are tuned to cancel the high-frequency pressure pulsations, whilst the active controller is designed to attenuate the dominant harmonic ripples. Adaptive notch filters with a variable step-size filtered-X Least Mean Square algorithm were applied in the new designed active piezoelectric actuator with high preload and operating forces, a wide bandwidth and very good linear dynamics. A time-domain hose model considering coupling of longitudinal wall and fluid waves was used to model and tune the flexible hose. Very good FBN cancellation was achieved by using the proposed integrated control approach, which was validated by comparing with numerical simulation and experiments. It can be concluded that the active attenuator with passive flexible hoses can form an effective, cost-efficient and practical solution for FBN attenuation. As the problem of high noise levels generated by hydraulically powered machines has risen significantly in awareness amongst industry and the general public, this work constitutes an important contribution to the sustainable development of low noise hydraulic fluid power machines.

The switched inertance hydraulic converter (SIHC) is a new technology providing an alternative to conventional proportional or servo-valve-controlled systems in the area of fluid power. SIHCs can adjust or control flow and pressure by means of using digital control signals that do not rely on throttling the flow and dissipation of power, and provide hydraulic systems with high-energy efficiency, flexible control, and insensitivity to contamination. In this article, the analytical models of an SIHC in a three-port flow-booster configuration were used and validated at high operating pressure, with the low- and high-pressure supplies of 30 and 90 bar and a high delivery flow rate of 21 L/min. The system dynamics, flow responses, and power consumption were investigated and theoretically and experimentally validated. Results were compared to previous results achieved using low operating pressures, where low- and high-pressure supplies were 20 and 30 bar, and the delivery flow rate was 7 L/min. We concluded that the analytical models could effectively predict SIHC performance, and higher operating pressures and flow rates could result in system uncertainties that need to be understood well. As high operating pressure or flow rate is a common requirement in hydraulic systems, this constitutes an important contribution to the development of newly switched inertance hydraulic converters and the improvement of fluid-power energy efficiency.