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Taking ischemic and bleeding risks into consideration, insufficient data exist on dual antiplatelet therapy after percutaneous coronary intervention in elderly Chinese patients with coronary artery disease.We aimed to investigate the effectiveness and safety of ticagrelor in comparison with clopidogrel on a background of aspirin for elderly Chinese patients with coronary artery disease 12 months after percutaneous coronary intervention.A single-center retrospective cohort study was conducted. Selected from patients with coronary artery disease aged ≥ 75 years from January 2010 to July 2019, 908 eligible subjects receiving dual antiplatelet therapy after percutaneous coronary intervention for up to 12 months were consecutively enrolled in the study. The included patients received ticagrelor in combination with aspirin (n = 264) or clopidogrel in combination with aspirin (n = 644). Effectiveness endpoints were evaluated by the major adverse cardiovascular events, encompassing all-cause death, non-fatal myocardial infarction, and clinically driven revascularization. The safety endpoints were recorded as the incidence of Bleeding Academic Research Consortium bleeding.The patients who were treated with ticagrelor were slightly younger than those who were treated with clopidogrel (79.1 ± 3.7 vs 80.7 ± 4.5 years, p0.01). The ticagrelor cohort contained a higher percentage of patients undergoing a prior percutaneous coronary intervention (37.9% vs 24.5%, p0.01), and a lower percentage of smokers (19.3% vs 27.2%, p0.05), compared with the clopidogrel cohort. The levels of glucose, total cholesterol, and low-density lipoprotein-cholesterol in the ticagrelor group were higher while the level of triglycerides and high-density lipoprotein-cholesterol were lower (p0.05) than those in the clopidogrel group. Left main percutaneous coronary intervention was performed more frequently among the ticagrelor-treated patients (23.5% vs 9.3%, p0.01), while patients in the clopidogrel group underwent more left circumflex percutaneous coronary intervention (34.3% vs 23.1%, p0.01). We found that ticagrelor was associated with a lower incidence of major adverse cardiovascular events than clopidogrel using the inverse probability of treatment weighting model (odds ratio, 0.493; 95% confidence interval 0.356-0.684). There was no difference in terms of the risk of Bleeding Academic Research Consortium bleeding between the two groups (p0.05).Ticagrelor was associated with a lower incidence of major adverse cardiovascular events than clopidogrel at 12 months in elderly Chinese patients with coronary artery disease, without a significant increase of Bleeding Academic Research Consortium bleeding events.

As a sister compound of MnBi2Te4, the high-quality MnSb2Te4 single crystals are grown via solid-state reaction where prolonged annealing and narrow temperature window play critical roles on account of its thermal metastability. Single-crystal X-ray diffraction (SCXRD) analysis on MnSb2Te4 illustrates a crystal model that is isostructural to MnBi2Te4, consisting of Te-Sb-Te-Mn-Te-Sb-Te septuple layers (SLs) stacking in an ABC sequence. However, MnSb2Te4 reveals a more pronounced cation intermixing in comparison with MnBi2Te4, comprising 28.9(7)% Sb antisite defects on the Mn (3a) site and 19.3(6)% Mn antisite defects on the Sb (6c) site, which may give rise to novel magnetic properties in emerging layered MnBi2Te4-family materials. Unlike the antiferromagnetic (AFM) nature in MnBi2Te4, MnSb2Te4 exhibits a glassy magnetic ground state below 24 K and can be easily tuned to a ferromagnetic state under a weak applied magnetic field. Its magnetic hysteresis, anisotropy, and relaxation process are investigated in detail via static and dynamic magnetization measurements. Moreover, anomalous Hall effect as a p-type conductor is demonstrated with transport measurements. This work grants MnSb2Te4 a possible access to the future exploration of exotic quantum physics by removing the odd/even layer number restraint in realizing quantum transport phenomena in intrinsic AFM MnBi2Te4-family materials, as a result of the crossover between its magnetism and potential topology arising from the Sb-Te layer.

This paper reports a simple-assembling synthesis of CuxO/C composite as the anode for lithium-ion batteries. The CuxO/C composite can be easily attained through using cotton as the template. Used as the anode material, the CuxO/C electrode has shown a relatively stable electrochemistry performance compared with the pristine CuO electrode. The cycling test results showed that the CuxO/C electrode achieved the steady specific capacity values of 381 mAhg−1 at 335 mAg−1 after 350 cycles while the capacity of the CuO electrode decreased after several cycles before it increased to 375 mAhg−1. This CuxO/C anode electrode stability is considered attributed to its core/shell structure, which can help keep the electrode structure stable during cycling.

In this paper, the reduced graphene oxide (rGO) and molybdenum disulfide (MoS2) (rGO-MoS2) heterostructures have been successfully synthesized by a facile hydrothermal method. The crystal phase, surface morphology, and chemical composition of the obtained heterostructures were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS) techniques. The electrochemical properties of the nitrite sensor attached with rGO-MoS2 heterostructures were investigated using cyclic voltammetry (CV) and single-potential amperometry methods. The measured results show that the as-prepared sensor based on rGO-MoS2/GCE exhibits a wide linear measurement range (0.2–4800 μM), low detection limit (0.17 μM), high sensitivity (0.46 μA μM−1 cm−2), and good selectivity and reproducibility towards nitrite detection. The anti-interference property and real sample analysis were also investigated, which shows that the as-prepared rGO-MoS2 heterostructures present great potential for practical applications.

Acetone detection at the parts-per-billion (ppb) level is achieved in this work using selective and optimized Fe doping of the three-dimensional (3D) flower-like SnO2 hierarchical microstructures. These structures were successfully synthesized via a one-step hydrothermal route. Detailed information about the crystal structure, surface morphology and composition of the Fe-doped SnO2 microstructures was investigated using X-ray diffraction (XRD), energy-dispersive spectroscopy (EDS), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS) techniques. Gas sensing experiments were conducted on the as-prepared Fe-doped SnO2 sensors. The measured results show that the incorporation of Fe into the SnO2 structure can greatly enhance the gas sensing properties of SnO2 sensors under the optimum working temperature (200 °C). Specifically, the 1.0 mol% Fe-doped SnO2 microstructures exhibit the highest response, fast response/recovery time, lowest detection limit and good selectivity and long-term stability. The results demonstrate that the developed Fe-doped SnO2 gas sensor has great potential for ppb-level acetone detection in many practical applications.

Background Contrast-induced nephropathy (CIN) is one of major and serious complications in patients undergoing percutaneous coronary intervention (PCI). It is unknown whether increased urinary adiponectin (UAPN), a sensitive marker for early renal function impairment, is associated with an increased risk of CIN. Therefore, we prospectively investigate the association of UAPN with CIN. Methods We prospectively enrolled 208 patients who were undergoing elective PCI. The baseline UAPN was assessed prior to PCI. The ROC analysis was used to evaluate the predictive value of UAPN for CIN. Multivariate logistic regression analysis was performed to analyze the independent risk factors for CIN. Results Of 208 patients, CIN occurred in 19 patients (9.13%), and 6 of them (2.88%) required dialysis. Patients with CIN had a higher UAPN level than those without CIN (17.15 ± 12.36 vs. 10.29 ± 3.04 ng/ml, P 124 μmol/L (OR, 4.210; 95% CI, 1.297–13.669; P

In this paper, brush-like ZnO nanowires were synthesized by two-step method combining electrospinning and hydrothermal. The phase purity, morphology, and structure of the brush-like ZnO hierarchical structures were characterized, which exhibited the improved surface area, comparing with ZnO nanofibers. The gas-sensing experiments were carried out on brush-like ZnO nanowires and ZnO nanofibers sensors under optimum working temperature. The highest response of brush-like ZnO nanowires to 100 ppm toluene and CO can reach to 12.7 and 5.9, respectively, which was much higher than that of ZnO nanofibers. Moreover, the brush-like ZnO nanowires sensor also shows fast response/recovery time to toluene (9/4 s) and CO (6/2 s), low detection limit (1 ppm to toluene). The measured results demonstrate that brush-like ZnO nanowires are potential as a novel sensing material for practical gas-sensing applications.

Pure ZnO and Pd/ZnO microstructures were prepared by hydrothermal method. The crystalline structures, morphology, and composition of synthesized hexagon hammer Pd/ZnO microstructures were analyzed by X-ray diffraction (XRD), scanning electron microscope (SEM), and energy dispersive X-ray spectroscopy (EDS). They were then studied for gas detection in order to achieve the optimal concentration of Pd in ZnO. Our results show that overall the Pd/ZnO microstructures have a better performance for ethanol detection comparing to the one without Pd, including a better sensitivity, a decreased operating temperature, and a shortened response/recovery time. At the optimal Pd concentration of 0.25 wt%, we observed a sensitivity enhancement of 3.5 times larger than that of ZnO without doping and a response and recovery time of 10 and 7 s, respectively. Moreover, the Pd/ZnO sensors could show a high selectivity and an excellent chemical stability, thereby providing a way to improve the gas sensing performances.

Hydrangea-like Ag@ZnO nanostructures were synthesized utilizing aqueous solution method, followed by calcination at different temperatures in air. The crystal structure, surface morphology and chemical state of synthesized nanostructures were analyzed. The results showed that hydrangea-like Ag@ZnO architectures exhibited the diameters in the range of 1.54–3.54 μm and decorated with Ag nanoparticles approximately 15 nm. The photocatalytic experiments were conducted on the as-prepared Ag@ZnO samples for photocatalytic degradation of rhodamine B after calcinations from 400 to 900 °C. The measured results demonstrate that both the calcination temperature and the content of Ag can significant influence the photocatalytic activities. Moreover, the 0.5 mol% Ag@ZnO exhibits the highest photocatalytic activity under the optimum calcination temperature of 700 °C. This study indicates that the as-prepared Ag@ZnO nanostructures have promising potential applications in the fields such as photocatalysis, solar energy conversion and sensing detection.

In contact UV lithography, a pair of cantilever beams fabricated by two inclined exposures at ±45° in SU-8 using a single mask will form a connected end on the top of SU-8 layer. These beams made of SU-8 with fixed-end have been used as optical fiber holders (Ling and Lian in Microsyst Technol 13(3–4):245–251, 2007). Recently, a two-mask, two-step process to fabricate free-end cantilever beams from SU-8 using inclined UV lithography has been developed (Ling et al. in Microsyst Technol 15(3):429–435, 2009), which has been successfully applied to fabricate SU-8 optical fiber holders with long free-end cantilever beams. In this process, two masks are needed in order to obtain free-end beams and the alignment between two exposures is always time consuming with limited accuracy. Two new techniques, inclined UV shadow mask lithography and inclined UV proximity lithography, have been illustrated here for fabricating free-end SU-8 cantilever beams, which eliminate the precise alignment step required in our previous work (Ling et al. in Microsyst Technol 15(3):429–435, 2009). In the inclined UV shadow mask lithography approach, the SU-8 cantilever beams without connected ends are formed by using one main mask and two shadow masks. Each shadow mask is used to selectively transfer one of the two separated patterns on main mask into SU-8 layer at +45° and −45°, respectively. In the inclined UV proximity lithography approach, a proper proximity gap between mask and SU-8 surface is obtained by using a 50 μm thick Mylar sheet, so that the exposing light paths that formed connected beam ends will fall inside the proximity layer instead of the SU-8. In this way, the desired open-end cantilever structures can be achieved. In this paper, the principles and the fabrication procedures of the proposed techniques are demonstrated and the preliminary results are discussed.

The optic alignment module containing out-of-plane 3D micro lenses, and micro optic fiber holders have been fabricated using tilted UV lithography technique in water with SU-8 photoresist (Ling and Lian in Proc SPIE 4979:402–409, 2007). Each holder is a circumscribed quadrilateral formed by a V-groove and pairs of fixed microclips, which will hold the fiber in position through the elastic deformation when the fiber is inserted. Since these microclips were fixed cantilever beams and its effective beam length, the distance between the fixed end of the beam and beam–fiber contact point, is very short (~62.5 μm), the stress on the beam is high even under a small (few microns) deformation. The inserted optical fiber was either too loose to lose its alignment accuracy, or too tight causing the clips to break because of dimensional tolerance. It becomes very difficult, if not impossible, to use them in practical applications. Therefore, the key issue of fabricating optical alignment module is to have a suitable stiffness of microclips with an appropriate deformation during the fiber insertion, which can provide enough force to hold the fiber for accurate alignment and avoid introducing neither significant viscous deformation nor the damage to the clips. In this paper, a novel technique to fabricate SU-8 cantilever beam as elastic clamping device in optical fiber holder is proposed. Simulation based on SU-8 material properties indicates that for a 250-μm-long, 50-μm-thick SU-8 beam the clamping force per unit beam width will range from 10 to 100 Newton/m as the deflection increased from 1.4 to 14 μm. This predicted performance is comparable to or even better than that of existing silicon nitride microclips in optical fiber holding application [Bostock et al. in J Micromech Microeng 8(4):343–360, 1998]. By using a two-mask process, we have fabricated free-end cantilever beams as fiber holding clips. In order to have longer beams over V-groove, the slots in the V-groove were introduced, which allow the beams extended deeper into the sloped V-groove walls. The micro alignment module with 250-μm-length cantilever beams as microclips for housing 125-μm-diameter optical fibers has been successfully fabricated using a 300-μm-thick SU-8 photoresist layer by a two-mask UV lithography processes. This approuch offers significant advantages over other techniques with respect to costs of material, simple in equipment, and easy in manufacture. These optical fiber holders with elastic microclips combined with pre-aligned out-of-plane 3D micro lenses make it possible that to build an integrated micro optic system with precise alignment accuracy on a wafer-scale.

This paper presents the important results of enhancing the boiling heat transfer of the pressurized water reactors (PWRs) by using LIGA or LIGA-like techniques to add microstructures on the surface of heater elements. The heater elements were made of 10 mm × 80 mm silicon strips with different in-line square micro-pin-fin configurations of 200 μm fin width, 35 μm fin height, and different inter-fin spacing values of 200, 400, 600, 800, 1000 μm and infinity. The experiments were conducted in de-ionized water at the atmospheric pressure. The input power, heater temperature, steam generation rate and video images of boiling phenomena were continuously recorded. Their relationships was studied and used to evaluate the total boiling heat transfer performance. The optimized microstructures can then be mass-fabricated on PWR tubes by using LIGA or LIGA-like technology. The experimental results suggest that by adding micro-sized in-line pin-fin arrays on heater surface and modifying heater surface morphology, the boiling process can be greatly enhanced through the improvements of vapor nucleation and vapor evolution processes at heater surface, which yields a low wall superheat and achieves a higher boiling heat transfer efficiency. The video images showed that the bubble nucleation sites are located immediately on top of each micro-pin fins. At current experimental setup, the 200 μm-spacing heater has the highest steam generation efficiency.

Comb-drive microactuator is widely used in MEMS devices and traditionally is made of silicon as structural material using silicon-based fabrication technology. Recent development in UV lithography of SU-8 has made it possible to fabricate the ultra high aspect ratio microstructures with excellent sidewall quality. In this paper, we report a low cost alternative to the silicon-based comb drive by using cured SU-8 polymer as structural material. The microactuator was designed to have a integrated structure without assembly or bonding. A unique integration fabrication process was successfully developed based on UV lithography of SU-8 and selectively metallizing SU-8 polymer structures. Preliminary experimental results have proved the feasibility of the microactuator and the fabrication technology.

Out-of-plane microlenses and microoptical fiber holder are two of the most important components for building an integrated microoptic system with a precise alignment accuracy. In this paper, a simple and convenient method to fabricate these components from SU-8 by using inclined UV lithography in water is proposed. It consists of two perpendicular exposures in SU-8 at ±45°. DI water possesses a low absorption coefficient and a moderate and stable value of refractive index in near UV. Using water, the exposure angle in SU-8 can be increased to 50° from 35° in air necessary to pattern the desired 45° slope of the sidewalls. The principle of the proposed technique and the detailed fabrication process of the microoptic components will be presented. The integratability of the fabricated components was demonstrated by the fabrication of the microoptical fiber holder with a pre-aligned out-of-plane microlens.

Electroplated nickel is the main material used in LIGA technique for fabricating MicroElectroMechanical System (MEMS) components. This paper presents the recent results regarding LIGA Ni material property enhancement at Center for Advanced Microstructures and Devices at Louisiana State University. The methodology of this study is based on the fundamental materials science paradigm that processing and manufacturing determine the microstructure of materials, which results in specific properties, and governs the performance of the structures that are made from these materials. This paper will focus on results in three aspects of our current research efforts, which are: (1) manipulating the plating parameters to tailor deposited Ni microstructures for different grain size distributions that are in the range of tens nanometer in diameters; (2) analyzing the mechanical properties, such as nano-hardness, micro-hardness, and wearing property as the function of LIGA Ni metallurgical microstructures; (3) estimating the corrosion properties of nanocrystalline LIGA Ni.

One of the major difficulties faced by MEMS researchers today is the lack of data regarding properties of electroplated metals or alloys of which microstructures and microdevices are fabricated, especially in LIGA technology. These mechanical properties cannot be extrapolated from macro-scale data without experimental verification. Therefore, study on material properties of microfabricated structures is of vital importance to the development of LIGA technology and to its industrial applications. This paper reports an experiment scheme and UV-LIGA microfabrication technology to study the fracture toughness of nickel micro specimens. The devised testing mechanism demonstrated compatibility with the fabricated samples and capability of performing the desired experimentation by generating resistance-to-fracture values of the nickel specimens. The same experiment scheme and sample fabrication technology can be used in future work to study the fracture toughness values for LIGA fabricated samples in various metals and alloys.

SU-8 has received wide attention in recent years because of its application in the fabrication of high aspect ratio microstructures and devices. This negative resist is known for its excellent lithography properties using ultraviolet light source. As the microfabrication technology based on UV-lithography of SU-8 finds wide applications, a good understanding and characterization of cured SU-8 polymer on various substrate materials are therefore very important. A good adhesion on various substrate materials is essential to both the fabrication process and to the functionality of any final products that have cured SU-8 as part of the structural material. There are very limited studies reported in this important area in the literature. This paper presents a theoretical and experimental work to quantitatively study the adhesion properties of cured SU-8 on some of the most commonly used metallic surface materials. The adhesion strengths of cured SU-8 samples on Au, Ti, Cu, Cr, and Ni coated glass substrates were measured following ASTM-C633 standard. A detailed analysis of the experimental results was also provided based on the atomic structures and electron configurations of the respective metals.

Many MEMS applications require multi-level microstructures in which two or more levels have to be aligned to each other in the processing. A passive alignment method based on a mechanical registration concept utilizing reference posts has been described in our early work [1]. An alignment accuracy of 1 μm for a two layers optical lithography has been achieved. In this paper the experimental results on improvement of the alignment accuracy and expanding this alignment method to multi-level X-ray or combined optical/X-ray lithography are presented.

This paper reports a research effort to design, microfabricate and test a DC type magnetohydrodynamic (MHD) micropump using LIGA method (Menz et al., 1991). The micropump is driven using the Lorentz force and can be used to deliver electrically conductive fluids. In operation, a DC voltage is supplied across the electrodes to generate the distributed body force on the fluid in the pumping chamber, and therefore a constant pressure difference along the pumping chamber. The external magnetic field was supplied using permanent magnets. The major advantage of a MHD-based micropump is that it does not contain any moving parts. It may have potential applications in medicine delivery, biological and biomedical studies. The test of the DC prototype micropump shows that bubble generation mechanism affect the performance significantly and an AC driving mechanism may be used to improve the performance.

Impaired mitochondrial biogenesis causes skeletal muscle damage in diabetes. However, whether and how mitochondrial biogenesis is impaired in the diabetic heart remains largely unknown. Whether adiponectin (APN), a potent cardioprotective molecule, regulates cardiac mitochondrial function has also not been previously investigated. In this study, electron microscopy revealed significant mitochondrial disorders in ob/ob cardiomyocytes, including mitochondrial swelling and cristae disorientation and breakage. Moreover, mitochondrial biogenesis of ob/ob cardiomyocytes is significantly impaired, as evidenced by reduced Ppargc-1a/Nrf-1/Tfam mRNA levels, mitochondrial DNA content, ATP content, citrate synthase activity, complexes I/III/V activity, AMPK phosphorylation, and increased PGC-1α acetylation. Since APN is an upstream activator of AMPK and APN plasma levels are significantly reduced in ob/ob mice, we further tested the hypothesis that reduced APN in ob/ob mice is causatively related to mitochondrial biogenesis impairment. One week of APN treatment of ob/ob mice activated AMPK, reduced PGC-1α acetylation, increased mitochondrial biogenesis, and attenuated mitochondrial disorders. In contrast, knocking out APN inhibited AMPK-PGC-1α signaling and impaired both mitochondrial biogenesis and function. The ob/ob mice exhibited lower survival rates and exacerbated myocardial injury after MI, when compared to controls. APN supplementation improved mitochondrial biogenesis and attenuated MI injury, an effect that was almost completely abrogated by the AMPK inhibitor compound C. In high glucose/high fat treated neonatal rat ventricular myocytes, siRNA-mediated knockdown of PGC-1α blocked gAd-enhanced mitochondrial biogenesis and function and attenuated protection against hypoxia/reoxygenation injury. In conclusion, hypoadiponectinemia impaired AMPK-PGC-1α signaling, resulting in dysfunctional mitochondrial biogenesis that constitutes a novel mechanism for rendering diabetic hearts more vulnerable to enhanced MI injury.

Effects of thickness and tip geometry on Ni thin films deposited on Cu substrate were studied using nanoindenter. The deformation mechanisms in correlation to hardness measurements were discussed at various loads and depths of penetration. The Berkovich, Cube corner and Conical tips have been used in this study. Initially, the hardness and modulus of elasticity were measured at a depth of 10% of film thickness. The depth of penetration was increased to 20% to observe the depth effects. Analysis of data showed that there is an Indentation Size Effect (ISE) irrespective of indenter tip geometries.