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ObjectiveTo evaluate the safety and clinical effect of tubular esophagogastric anastomosis in laparoscopic radical proximal gastrectomy.MethodsA retrospective analysis was conducted involving 191 patients who underwent laparoscopic radical proximal gastrectomy in the Department of Gastrointestinal Surgery, Qilu Hospital of Shandong University from January 2017 to October 2020. Patients were divided into tubular esophagogastric anastomosis group (TG group) and traditional esophagogastric anastomosis group (EG group) according to the digestive tract reconstruction. Their intraoperative conditions, perioperative recovery and postoperative follow-up were compared. Patients were also divided into indocyanine green group and non-indocyanine green group according to whether or not indocyanine green tracer technology was used during the operation. Their intraoperative condition and perioperative recovery were compared and analyzed after propensity score matching.ResultsThe operation was successfully completed in all patients. Compared with the EG group, the TG group had less volume of gastric tube drainage, shorter gastric tube drainage time and proton pump inhibitors application time, and lower reuse rate of proton pump inhibitors. However, the TG group had a higher anastomotic stenosis at three months after surgery, as measured using anastomotic width and dysphagia score. Nevertheless, the incidence of reflux esophagitis and postoperative quality of life score in the TG group were lower compared with the EG group at 1st and 2nd year after surgery. In the indocyanine green analysis, the indocyanine green group had significantly shorter total operation time and lymph node dissection time and less intraoperative blood loss compared with the non-indocyanine green group. However, compared with the non-indocyanine green group, more postoperative lymph nodes were obtained in the indocyanine green group.ConclusionLaparoscopic radical proximal gastrectomy is safe and effective treatment option for upper gastric cancer. Tubular esophagogastric anastomosis has more advantages in restoring postoperative gastrointestinal function and reducing reflux, but it has a higher incidence of postoperative anastomotic stenosis compared with traditional esophagogastrostomy. The application of indocyanine green tracer technique in laparoscopic radical proximal gastrectomy has positive significance.

Hafnium oxide (HfO2) fibers can be widely used in ultra-high temperature ceramics (UHTCs) as reinforced material in order to achieve better antioxidant performance and less cracks and flaking on surface of UHTCs in field of ultra-high temperature thermal protectors. Calcination temperature is one of essential parameters for forming HfO2 fiber. In this work, one-dimensional (HfO2) fibers were prepared through the electrospinning method and further post-calcination treatment. During the calcination treatment, the monoclinic-HfO2 (m-HfO2) was formed from as-spun HfO2 fibers at 432 °C, and only a small amount of m-HfO2 was converted into the tetragonal HfO2 at 1013 °C, which can increase the fiber density and decrease the grain size. However, the remaining m-HfO2 was directly converted into the cubic HfO2 at 1351 °C. The unique temperatures of forming monoclinic, tetragonal, cubic phase were much lower than the phase-transition temperature. The prepared HfO2 fiber could still maintain fibrous morphology after 10 times cyclic thermal shock in air. Moreover, the fibers calcined at 900 °C and 1200 °C have better thermal shock resistance for their stable phase and fibrous morphology with uniform grain growth after the thermal shock test.

Magnetic field sensors are important in a variety of applications, including transport and medical devices. However, existing solid-state approaches for the detection of three-dimensional magnetic fields require multiple sensors, making the set-ups bulky. Here, we show that a single spin–orbit torque device composed of a Ta/CoFeB/MgO heterostructure can detect a vector magnetic field. In-plane and out-of-plane field components lead to the displacement of domain walls in the CoFeB layer, modulating the associated anomalous Hall effect resistance. Modulation of the anomalous Hall effect resistance varies linearly with the x, y and z components of a vector magnetic field. Our compact three-dimensional magnetic field sensor exhibits good linearity within a certain range (3.2%, 2.7% and 4.3% for the x, y and z directions, respectively) and high sensitivity (205, 282 and 1,845 V A−1 T−1 for the x, y and z directions, respectively). The sensor also exhibits low 1/f noise. Changes in the anomalous Hall resistance of a single device comprising a Ta/CoFeB/MgO heterostructure can be used to probe three-dimensional magnetic fields with high sensitivity and good linearity.

Magnetic anomaly detection is an effective method for detecting ferromagnetic targets. The practical application of target detection by measuring the magnetic gradient has been confirmed in many studies, and its suppression of background noise has been widely recognized. However, the variation of the unidirectional magnetic field gradient is very small in a short distance, and the amplitude of the signal is also affected by the direction of the target’s magnetic moment and the shaking of the sensor platform itself. These make it difficult to extract the signal from complex background interference. In order to solve these problems, this paper is devoted to use the variation of three axial magnetic gradients in the geomagnetic coordinate system caused by the presence of magnetic target (we call it full magnetic gradient) to construct the magnetic anomaly characteristic of the target. A set of orthonormal basis functions is further derived to linearly describe this characteristic, which improves the signal-to-noise ratio (SNR) of the signal from the perspective of signal energy. The present work main contribution is to propose a full magnetic gradient orthonormal basis function (FMG-OBF) method to effectively characterize magnetic anomaly of magnetic targets. Compared with the traditional one-direction magnetic gradient orthonormal basis function method, the SNR of this method is greatly improved, and it is not affected by a change in the target magnetic moment’s direction nor by the shaking of the sensor carrier platform. Therefore, it has great value in the practical application of aeromagnetic detection.

Heat flux sensors (HFSs) are extensively used in combustion-related applications to collect important engineering data. However, most non-water cooling HFSs lack the durability to survive in the harsh, high-temperature environments where they are employed. A new type of thin-film HFS based on a W-5Re/W-26Re thermocouple has been developed for high-temperature heat flux measurement. The sensor consists of 136 pairs of micron-sized W-5Re/W-26Re thin-film thermocouples, an SiO2 thermal-resistance layer, and an AlN substrate. The SiO2 layer is sandwiched between the substrate and thermocouples, and allows the measurement of temperature differences arising from the difference in thermal conductivity between the substrate and the SiO2 layer. A protective layer with a sandwich structure prevents the tungsten-rhenium thin film from oxidizing at high temperatures in air. This small HFS with a protective layer can survive for 1 h in 1000°C air. Calibration data show that the HFS exhibits repeatable and fast thermal responses when a pulsed heat flux of 1000 kW/ $\text{m}^{2}$ is applied, and its sensitivity is 3.8* $10^{-6}$ V/(kW/ $\text{m}^{2}$ ). The experimental data agree with the simulated results. It can be concluded from the experimental results that the tungsten-rhenium thin film has a good thermoelectric response to high temperatures after the size is reduced to a micron. Thus the developed HFS can be a suitable alternative for applications in thermal systems, such as engines, turbines, and rockets.

We present the fabrication and characterization of an array of microbridge-structured magnetoelectric (ME) thin film sensors which are constructed by an ME composite consisting of a 1 $\mu \text{m}$ PZT film and a 1 $\mu \text{m}$ amorphous FeCoSiB film deposited on a partially thinned Si substrate. Characterization of the sensor showed a large ME coefficient of $16.87~\text {V/cm}\cdot \text {Oe}$ in resonance at 7.9 kHz without a charge amplifier. The sensitivity was enhanced by 1.65 times when three identical sensors were connected in series. The resonant frequency of the sensor was precisely regulated by adjusting the etched area of the substrate, and the 3 dB bandwidth of the resonant frequency was doubled after two adjusted sensors were connected in parallel.

Supplying wireless power is a challenging technical problem of great importance for implantable biomedical devices. Here, we introduce a novel implantable piezoelectric ultrasound energy–harvesting device based on Sm-doped Pb(Mg 1/3 Nb 2/3 )O 3 -PbTiO 3 (Sm-PMN-PT) single crystal. The output power density of this device can reach up to 1.1 W/cm 2 in vitro, which is 18 times higher than the previous record (60 mW/cm 2 ). After being implanted in the rat brain, under 1-MHz ultrasound with a safe intensity of 212 mW/cm 2 , the as-developed device can produce an instantaneous effective output power of 280 μW, which can immediately activate the periaqueductal gray brain area. The rat electrophysiological experiments under anesthesia and behavioral experiments demonstrate that our wireless-powered device is well qualified for deep brain stimulation and analgesia applications. These encouraging results provide new insights into the development of implantable devices in the future.

This study investigated the efficacy of extracorporeal shock wave therapy as well as the optimal intervention timing for extracorporeal shock wave therapy for patients with spasticity after stroke.A search of randomized controlled trials was conducted in different electronic databases. We performed a meta-analysis to measure the effect of extracorporeal shock wave therapy versus sham interventions on spasticity and limb functionality. The meta-regression analysis was performed to determine the adequate intervention timing of extracorporeal shock wave therapy. The follow-up period of the outcomes was divided into the short (2 wks), mid (2 wks and ≤4 wks), and long (4 wks and ≤3 mos) terms.Thirteen studies with 677 participants were evaluated. Spasticity significantly improved throughout the follow-up duration. Limb functionality significantly improved in the short-term follow-up period. The meta-regression analysis showed that patients with stroke duration less than 45 mos may be benefited from extracorporeal shock wave therapy in improving limb function in all follow-up periods.Extracorporeal shock wave therapy is an effective method for reducing spasticity in patients with stroke, and the effect could be maintained for up to 3 mos. Its effects on limb functionality could persist for at least 2 wks. Patients who had stroke for less than 45 mos may have significant benefit from extracorporeal shock wave therapy in all follow-up periods.

Transcranial focused ultrasound (tFUS) is regarded as a promising non-invasive stimulation tool for modulating brain circuits. The aim of this study is to explore the feasibility of tFUS stimulation for analgesia applications.50 µl of 3% formalin solution was injected into the rat's left hindpaw to build a pain model, and then the local field potential (LFP) activities of the dorsal horn were tracked after a recording electrode was placed in the spinal cord. Rats were randomly divided into two groups: control group and tFUS group. At the 30The tFUS stimulation of the PAG can suppress effectively the nociceptive activity generated by formalin. The findings of the underlying mechanism exploration indicated that the tFUS stimulation was able to activate the PAG directly without causing notable temperature change and tissue injury.The results illustrated that the tFUS stimulation of the PAG can achieve the effect of analgesia.This work provides new insights into the development of non-invasive analgesic technology in the future.

Percutaneous vertebroplasty (PVP) via the unilateral posterosuperior approach has achieved good clinical results for the treatment of osteoporotic vertebral compression fractures. This study compared the biomechanical performance of a single vertebral body after PVP by the unilateral posterosuperior, unipedicular, and bipedicular approaches. Twenty-one vertebral bodies from the osteoporotic spine segments (T11-L1) of seven older female cadavers were randomly assigned to the unipedicular (group A), bipedicular (group B), or unilateral posterosuperior approach group (group C). After constructing the fracture compression model, PVP was performed by the different approaches. CT scans showed symmetrical, evenly distributed bone cement in groups B and C and unilaterally distributed cement in group A. The recovery rates of the anterior vertebral body height in groups B and C were significantly higher than those in group A after PVP (P0.05) and higher than those in group A (P

The goal was to simply and efficiently predict the indicators of disease severity in knee osteoarthritis (KOA) patients.One hundred eighty-four patients with KOA and 126 healthy subjects were included. WOMAC (Western Ontario and McMaster Universities Osteoarthritis Index) was used as a reference index for disease severity in KOA patients, in which WOMAC80 was classified as mild and WOMAC ≥ 80 as moderate and severe. Blood routine parameters of the KOA and the healthy groups were analyzed by the Mann Whitney U test. Receiver operating characteristic curves were used to analyze the sensitivity and specificity of mean corpuscular hemoglobin and platelet distribution width ratio (MPR) and monocyte and hemoglobin ratio (MHR) indicators. The correlation between MPR and MHR and disease severity of KOA was determined by bivariate regression analysis. Independent predictors of disease severity in patients with KOA were assessed by multivariate regression analysis.MPR, MHR, and WOMAC were significantly higher in the KOA group. The ROC curve indicated that the cutoff values of MPR and MHR were 2.09 and 0.0030, respectively, with sensitivity of 86.4% and 68.5% and specificity of 99.2% and 79.4%. Bivariate regression analysis found that MPR was better correlated with disease severity than MHR. The results of multivariate regression analysis demonstrated that the MPR values of moderate and severe patients were more than 19 times that of mild patients, and the OR values were 21.695 and 19.558, respectively.MPR and MHR demonstrated a good correlation with disease severity in patients with KOA. MPR is a potential independent predictor of disease severity in patients with KOA.

To achieve the anatomical evaluation of spinal nerve and cervical intervertebral foramina in anterior controllable antedisplacement and fusion (ACAF) surgery, a novel surgical technique with the wider decompression, through a cadaveric and radiologic study.Radiographic data of consecutive 47 patients (21 by ACAF and 26 by anterior cervical corpectomy and fusion [ACCF]) who have accepted surgery for treatment of cervical ossification of the posterior longitudinal ligament(OPLL) and stenosis from March 2017 to March 2018 were retrospectively reviewed and compared between an ACAF group and ACCF group. Three postoperative radiographic parameters were evaluated: the decompression width and the satisfaction rate of decompression at the entrance zone of intervertebral foramina on computed tomography (CT), and the transverse diameter of spinal cord in the decompression levels on magnetic resonance imaging (MRI). In the anatomic study, three fresh cadaveric spines (death within 3 months) undergoing ACAF surgery were also studied. Four anatomic parameters were evaluated: the width of groove, the distance between the bilateral origins of ventral rootlets, the length of ventral rootlet from their origin to the intervertebral foramina, the descending angle of ventral rootlet.The groove created in ACAF surgery included the bilateral origins of ventral rootlets. The rootlets tended to be vertical from the rostral to the caudal direction as their takeoff points from the central thecal sac became higher and farther away from their corresponding intervertebral foramina gradually. No differences were identified between left and right in terms of the length of ventral rootlet from the origin to the intervertebral foramina and the descending angle of ventral rootlet. The decompression width was significantly greater in ACAF group (19.2 ± 1.2 vs 14.7 ± 1.2, 21.3 ± 2.2 vs 15.4 ± 0.9, 21.5 ± 2.1 vs 15.7 ± 1.0, 21.9 ± 1.6 vs 15.9 ± 0.8, from CACAF can decompress the entrance zone of intervertebral foramina effectively and its decompression width includes the origins and massive running part of bilateral ventral rootlets. Due to its wider decompression range, ACAF can be used as a revision strategy for the patients with failed ACCF.

CNT-PDMS composite is regarded as a promising candidate for optoacoustic transducer application. However, the relationship between the CNT thermal conductivity and optoacoustic transducer performance is still undefined. To explore this relationship, four types of CNTs with different diameters and lengths were employed to successfully fabricate four types of optoacoustic transducers. The thermal properties of CNTs were analyzed and discussed in this paper; the laser-generated ultrasound and optoacoustic conversion efficiency of the transducers were experimentally and theoretically investigated. Results of comparison revealed the CNT with a diameter and length of 8 nm and 10–30 μm, respectively, to have the highest thermal conductivity. With this type of CNT/PDMS composite, the optoacoustic conversion efficiency reached as high as 9.59 × 10−3. Overall, the results demonstrate that higher CNT thermal conductivity corresponds to better optoacoustic transducer performance.

Recently, super-harmonic ultrasound imaging technology has caused much attention due to its capability of distinguishing microvessels from the tissues surrounding them. However, the fabrication of a dual-frequency confocal transducer is still a challenge. In this work, 270- $\mu \text{m}$ PMN-PT single crystal 1–3 composite and 28- $\mu \text{m}$ PVDF thick film, acting as transmission layer and receiving layer, respectively, are integrated in a novel co-focusing structure. To realize delicate wave propagation control, microwave transmission line theory is introduced to design such structure. Two acoustic filter layers, 13- $\mu \text{m}$ copper layer and 39- $\mu \text{m}$ Epoxy 301 layer, are indispensable and should be added between two piezoelectric layers. Therefore, an acoustic issue can be overcome via an electrical method and the successful achievement of a dual-frequency (5 MHz/30 MHz) ultrasound transducer with a confocal distance of 8 mm can be realized. The super-harmonic ultrasound imaging experiment is conducted using this kind of device. The 3-D image of 110- $\mu \text{m}$ -diameter phantom tube injected with microbubbles can be obtained. These promising results demonstrate that this novel dual-frequency (5 MHz/30 MHz) confocal ultrasound transducer is potentially usable for microvascular medical imaging application in the future.

Background Pressure support ventilation (PSV) is the prevalent weaning method. Proportional assist ventilation (PAV) is an assisted ventilation mode, which is recently being applied to wean the patients from mechanical ventilation. Whether PAV or PSV is superior for weaning remains unclear. Methods Eligible randomized controlled trials published before April 2020 were retrieved from databases. We calculated the risk ratio (RR) and mean difference (MD) with 95% confidence intervals (CIs). Results Seven articles, involving 634 patients, met the selection criteria. Compared to PSV, PAV was associated with a significantly higher rate of weaning success (fixed-effect RR 1.16; 95% CI 1.07–1.26; I2 = 0.0%; trial sequential analysis-adjusted CI 1.03–1.30), and the trial sequential monitoring boundary for benefit was crossed. Compared to PSV, PAV was associated with a lower proportion of patients requiring reintubation (RR 0.49; 95% CI 0.28–0.87; I2 = 0%), a shorter ICU length of stay (MD − 1.58 (days), 95% CI − 2.68 to − 0.47; I2 = 0%), and a shorter mechanical ventilation duration (MD − 40.26 (hours); 95% CI − 66.67 to − 13.84; I2 = 0%). There was no significant difference between PAV and PSV with regard to mortality (RR 0.66; 95% CI 0.42–1.06; I2 = 0%) or weaning duration (MD − 0.01 (hours); 95% CI − 1.30–1.28; I2 = 0%). Conclusion The results of the meta-analysis suggest that PAV is superior to PSV in terms of weaning success, and the statistical power is confirmed using trial sequential analysis. Graphical abstract

Based on a modified dice-and-fill technique, a PIN-PMN-PT single crystal 1-3 composite with the kerf of 12 &mu, m and pitch of 50 &mu, m was prepared. The as-made piezoelectric composite material behaved with high piezoelectric constant (d33 = 1500 pC/N), high electromechanical coefficient (kt = 0.81), and low acoustic impedance (16.2 Mrayls). Using lithography and flexible circuit method, a 48-element phased array was successfully fabricated from such a piezoelectric composite. The array element was measured to have a central frequency of 20 MHz and a fractional bandwidth of approximately 77% at &minus, 6 dB. Of particular significance was that this PIN-PMN-PT single crystal 1-3 composite-based phased array exhibits a superior insertion loss compared with PMN-PT single crystal and PZT-5H-based 20 MHz phased arrays. The focusing and steering capabilities of the obtained phased array were demonstrated theoretically and experimentally. These promising results indicate that the PIN-PMN-PT single crystal 1-3 composite-based high frequency phased array is a good candidate for ultrasound imaging applications.

The stress-induced magnetic anisotropy can significantly affect giant magneto-impedance (GMI) effect of the soft magnetic film. This paper is devoted to the GMI effect of the single layer soft magnetic film implied without and with a stress. By simulating a physical model with MATLAB and COMSOL software, the impedance expression of the single layer soft magnetic film and the relation between external magnetic field and magnetic permeability are deduced. We observed that, without a stress, the sensitive region increased firstly and then decreased with the increasing of the excitation current frequency from 1 MHz to 200 MHz. While the film was subjected to the stress in the direction of the current with one end stressed, the stress on the film was gradually reduced from stressed end to free end. Also, the impedance change rate of the film changed when the stress was added, which is similar to the effect of adding a bias magnetic field on the film. More importantly, the addition of stress σ can induce the bias of the GMI measurement range and improve its sensitivity near zero magnetic fields. This may provide a new way for designing a GMI sensor with higher sensitivity and adjustable measurement range.

In this paper, we studied a highly isotropic sensor for scalar magnetic field measurements and developed a Terfenol-D/PZT composite magnetoelectric sensor based on a nested ring structure. The effect of applied magnetic field, direction, and bias magnetic field on the output characteristics of the structure was studied, and it was observed that it has good linearity and a wide measurement range. According to a linear theoretical model suitable for small-signal excitation, when the direction of the applied ac magnetic field changes, the ratio of the maximum and minimum output voltages is only 3:1. Both experimental and theoretical results demonstrate that the nested-ring-structured sensor is highly isotropic. It is observed that the isotropy of the magnetoelectric sensor depends not only on the shape isotropy of the piezoelectric and magnetostrictive materials but also on the amplitude of the bias magnetic field.

Using a novel lapping technology, the achievement of approximately 28 μm (K0.45Na0.55)0.96Li0.04NbO3 (abbreviated as KNLN) single crystal thick film with orientation has been realized. This kind of thick film exhibited excellent electrical performance: a superior piezoelectric constant (~ 490 pm/V) and an outstanding electromechanical coupling coefficient (kt ~ 0.55). Based on the obtained KNLN single crystal thick film, a tiny side-looking 82 MHz ultrasound transducer with a bandwidth of 57.3% at − 6 dB has been successfully fabricated. Most importantly, 80 MHz intravascular ultrasound and photoacoustic images of the healthy rabbit aorta have been presented. All these promising results indicate that KNN-based single crystal thick film is a good environmental protection candidate for high frequency (~ 80 MHz) ultrasound applications.

Carbon Nanotube assemblies are currently of considerable interest for their properties of high-packing-density and aligned configurations, which offer a promising route to achieve higher strength and conductivity in macroscopic materials. While most researches have focused on their mechanical and electrical properties, recently, their light absorption and thermal conductivity have attracted more and more attention. This work introduces a novel freestanding optoacoustic transducer using continuous multilayered carbon nanotube yarns, gold nanoparticles and elastomeric polymer, which can be used for efficient conversion from laser energy to acoustic power and generating high acoustic pressure (~33.6 MPa) without focusing. The calculated energy conversion efficiency is as high as 2.74 × 10−2. Such excellent performances could be attributed to its freestanding structure and the enhanced optical absorption due to localized surface plasmon resonance (LSPR) caused by gold nanoparticles. The laser-generated ultrasound has been experimentally demonstrated to be capable of manipulating micro particles (50 µm) in a transparent channel.

The CXC chemokines are unique cytokines that play a vital role in the progression of many cancers. Association between chemokine (C-X-C motif) receptor 2 (IL8RB) C1208T mutation and cancer risk remains incomprehensive.We therefore utilized odds ratios and in silico analysis to explore the relationship of IL8RB polymorphism on risk to cancer. Furthermore, we adopted gene set enrichment analysis to investigate the IL8RB expression in prostate adenocarcinoma.A total of 14 case-control studies combined with 5299 cases and 6899 controls were included in our analysis. We revealed that individuals carrying TT genotype had an 14% increased cancer risk compared with those with TC + colon cancer (CC) genotype (odds ratio [OR] = 1.14, 95% CI = 1.05-1.25, P = .003, I2 = 35.6). Stratification analysis by race showed that East Asians with TT + TC genotype may have a 25% decreased cancer risk compared with control. Stratification analysis by cancer type revealed that individuals with TT genotype were associated with elevated risk of urinary cancer than control. The expression of IL8RB was attenuated in prostate adenocarcinoma.IL8RB C1208T may be correlated with the risk of cancer, especially prostate adenocarcinoma.

Many studies on the protection of C/C composites in oxidizing environments have been carried out. Coating technology has proven to be highly effective in improving the oxidation resistance of C/C composites. Summaries and comparisons of antioxidation coating materials for C/C composites are needed for comprehensive understanding and further researches. In this paper, recent advances in promising single-phase materials as protective coatings for C/C composites were firstly reviewed, with attention to their characteristics and antioxidation mechanisms. Then, several common mixture systems, such as carbide mixtures, boride mixtures and MoSi2-based ultrahigh-temperature ceramics (UHTCs), were discussed. In addition, three kinds of nanostructured materials used for doping coatings were described in detail. Finally, some typical problems and future challenges in the development of these coating materials for C/C composites were highlighted.

Microwave ferrites with low microwave loss and strong magnetoelectric (ME) or magnetodielectric (MD) effect are of great importance for real time tunable microwave devices used in modern communication systems among other applications. In this work, the crystalline structure, static magnetic characteristics, microwave electromagnetic properties and microwave magnetodielectric effect in polycrystalline YbxY3-xFe5O12 (x = 0∼3) ceramics have been systematically analyzed. The maximum MD response was measured to be -3.29%∼+2.9% at 2–8 GHz under an applied DC magnetic field, H, of 1650 Oe. The experimental results reveal that the microwave magnetodielectric behaviors of Yb-doped YIG ceramics will be influenced comprehensively by variations in crystal structure resulted from Yb substitution, which is interpreted in terms of energy conversion model. We believed the present work will prove enabling to further understand and lead to more effective applications of the ME/MD effect.

This paper introduces an innovative way to prepare lead zirconate titanate thick films near the morphotropic phase boundary using oil-bath based hydrothermal method with magnetic stirring. Undergoing once nucleation process and four-time crystallization process, approximately 10 µm PZT thick films could be obtained. This PZT film performed good ferroelectric and dielectric property. At room temperature, the coercive field (E c ) and the remnant polarization (P r ) were 37.5 kV/cm and 7 μC/cm 2 , respectively. In the frequency range between 1 kHz to 1 MHz, dielectric constant decreased from 300 to 250 and the dielectric loss was below 0.1. These promising results suggest that the oil-bath based hydrothermal method is a good candidate for PZT film fabrication.

The electric filed-induced multi-jump magnetic switching based on multiferroic heterostructure is studied using micromagnetic simulation software. The model consists of CoFe 2 O 4 thin film with magnetocrystalline anisotropy and PZN-PT substrate. The magnetic field is applied in plane along different directions with the electric field ( E ) applied through the thickness of substrate varying from 0 to 2.0 MV/m. The results reveal that the strain produced by the substrate induces an in-plane uniaxial anisotropy. The effective anisotropy of film changes from fourfold to twofold symmetry under E . When magnetic field is along specific directions, the multi-jump magnetic switching process can be induced by electric fields. Typically, when the angle between magnetic field and [100] direction is 75°, and E = 2.0 MV/m, the switching process from one to two or three jump can be observed when E increases from 0 to 2.0 MV/m. This appearance of multi-jump switching is attributed to the abrupt variation of the magnetization direction for the minimum energy density induced by the electric field.

An approximately 40μm pyrochlore-free lead magnesium niobate-lead titanate [0.65Pb(Mg1/3Nb2/3)O3–0.35PbTiO3, PMN–PT] thick film with cylindrically-concaved structure was successfully prepared using a pad printing technology. The optimum sintering temperature was found to be 800 °C and the obtained sample exhibited good dielectric and ferroelectric properties. Curie temperature, room temperature relative permittivity, dielectric loss and remnant polarization of this kind of PMN-PT thick film were 172 °C, 2638, 0.025 and 25 μC/cm2, respectively, which are comparable to the reported values for planar PMN-PT thick film. These promising results indicate that pad printing technology is an effective way to fabricate high performance cylindrically-concaved thick film and this obtained PMN-PT thick film may be a good candidate for high frequency focused ultrasound array application.

The electric field control of the exchange spring (ES) effect in perpendicularly magnetized bilayers is studied using micromagnetic simulation. The ES bilayer with a total thickness of 20 nm is composed of a FePt layer with perpendicular magnetic anisotropy (PMA) and a NiFe layer with in-plane anisotropy. The thickness ratio between the FePt and NiFe layers (TRFN) is varied. Single-crystal lead zinc niobate-lead titanate (PZN-PT) forms the piezoelectric substrate, and electric fields are applied across the thickness of the substrate to induce in-plane stress. The results reveal that application of a negative electric field E reduces the switching field (HS) and squareness ratio (MR/MS) but enhances the nucleation field (HN), while applying a positive E has a negligible effect on these parameters. When the TRFN is 18:2, an electric field of −2 MV/m reduces HS by 5.5% while MR/MS is maintained at 1. This indicates that when the FePt content is sufficiently large, applying a strong negative E can reduce HS without changing MR/MS. Based on the simulation results, we propose a model for electrically assisted magnetic memory.

microRNA, a family of small non-coding RNA, plays significant roles in regulating gene expression, mainly via binding to the 3'-untranslated region of target genes. Although the role of miRNA in regulating neuroinflammation via the innate immune pathway has been studied, its role in the production of inflammatory mediators during microglial activation is poorly understood. In this study, we investigated the effect of miR-27a on lipopolysaccharide (LPS)-induced microglial inflammation. miR-27a expression was found to be rapidly decreased in microglia by real-time polymerase chain reaction (real-time PCR) after LPS stimulation. Over-expression of miR-27a significantly decreased the production of inflammatory cytokines, such as interleukin-6 (IL-6), interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α), and nitric oxide (NO), whereas knockdown of miR-27a increased the expression of these inflammatory factors. We also demonstrated by loss- and gain-of-function studies that miR-27a directly suppressed the expression of toll-like receptor 4 (TLR4) and interleukin-1 receptor-associated kinase 4 (IRAK4)-a pivotal adaptor kinase in the TLR4/MyD88 signaling pathway-by directly binding their 3'-UTRs: knocking down TLR4 or IRAK4 in microglia significantly decreased TLR4 or IRAK4 expression and inhibited the downstream production of inflammatory mediators. Moreover, the inflammatory cytokines IL-6 and IL-1β were regulated by IRAK4, whereas TNF-α and NO were more dependent on TLR4 activation. Thus, miR-27a might regulate the LPS-induced production of inflammatory cytokines in microglia independently of TLR4 and IRAK4. Taken together, our results suggest that miR-27a is associated with microglial activation and the inflammatory response.