In this work, TiO2/CdS nanocomposites with co-exposed {101}/111-facets (NH4F-TiO2/CdS), {101}/{010} facets (FMA-TiO2/CdS), and {101}/{010}/111-facets (HF-TiO2/CdS and Urea-TiO2/CdS) were successfully ...synthesized through a one-pot solvothermal method by using Ti4O92− colloidal solution containing CdS crystals as the precursor. The crystal structure, morphology, specific surface area, pore size distribution, separation, and recombination of photogenerated electrons/holes of the TiO2/CdS nanocomposites were characterized. The photocatalytic activity and cycling performance of the TiO2/CdS nanocomposites were also investigated. The results showed that as-prepared FMA-TiO2/CdS with co-exposed {101}/{010} facets exhibited the highest photocatalytic activity in the process of photocatalytic degradation of methyl orange (MO), and its degradation efficiency was 88.4%. The rate constants of FMA-TiO2/CdS was 0.0167 min−1, which was 55.7, 4.0, 3.7, 3.5, 3.3, and 1.9 times of No catalyst, CdS, HF-TiO2/CdS, NH4F-TiO2/CdS, CM-TiO2, Urea-TiO2/CdS, respectively. The highest photocatalytic activity of FMA-TiO2/CdS could be attributed to the synergistic effects of the largest surface energy, co-exposed {101}/{010} facets, the lowest photoluminescence intensity, lower charge-transfer resistance, and a higher charge-transfer efficiency.
In this study, the efficiency of a large aperture 2-stage parabolic trough concentrator (PTC) is improved using an innovative design method for the secondary reflector (SR). The design method is ...based on an adaptive approach in which the SR is step-wise optimized to maximally reflect back to the absorber tube (AT) the part of solar radiation reflected by the primary reflector (PR) but not captured by the AT. The adaptive design method results in a SR design which consists of several parabolas with different focal lengths, each having a focus which lies in the focus of the PR. This ensures that the originally unabsorbed solar radiation will now hit the surface of AT. The optical efficiency of the PTC could be increased by 5.2% and thermal efficiency by 4.9%, respectively, compared to a case without optimized SR. In addition, the uniformity of the solar radiation flux on the AT’s outer wall could be doubled, its temperature was more even. The new adaptive design approach of the SR could help to better optimize PTC systems.
•New design approach for secondary mirror in parabolic trough concentrator.•Adaptive method to design secondary mirror.•Step-wise optimization to maximally reflect radiation to absorber.•Optical and thermal efficiency of concentrator increased by 5.2% and 4.9%.
Triple-negative breast cancer (TNBC) represents up to 20% of all breast cancers. This cancer lacks the expression of the estrogen receptor, progesterone receptor, and human epidermal growth factor ...receptor 2. The current therapeutic strategy for patients with this subtype is the use of cytotoxic chemotherapy and surgery. Luteolin is a natural herbal flavonoid and a potential therapeutic candidate for multiple diseases. The use of a treatment that combines Chinese herbal medicine and western medicine is rising in Asia.
The present study evaluates the effects and molecular mechanisms involved with luteolin treatment and evaluates whether this herb affects androgen receptor-positive breast cancer cell proliferation or metastasis.
In vitro evaluation of the effect of luteolin on androgen receptor-positive TNBC cell proliferation and metastasis
Cell viability analysis was used for the cytotoxicity test. Colony formation and Bromodeoxyuridine (BrdU) staining-based proliferation experiments were used for cell proliferation. Wound healing and transwell assays were used for in vitro migration/invasion. The RT-qPCR analysis was used for gene expression. Furthermore, ChIP-qPCR analysis was used for epigenetic modification of gene promoters.
Luteolin significantly inhibited the proliferation and metastasis of androgen receptor-positive TNBC. Furthermore, luteolin inactivated the AKT/mTOR signaling pathway and reversed the epithelial-mesenchymal transition (EMT). The combination of luteolin and inhibitors of AKT/mTOR synergistically repressed an androgen receptor-positive TNBC cell proliferation and metastasis. Luteolin also downregulated MMP9 expression by decreasing the levels of the AKT/mTOR promoting H3K27Ac and H3K56A on the MMP9 promoter region.
Our findings indicate that luteolin inhibited the proliferation and metastasis of androgen receptor-positive TNBC by regulating MMP9 expression through a reduction in the levels of AKT/mTOR-inducing H3K27Ac and H3K56Ac.
Display omitted
The micro-actuator is a key element of the MEMS-based initiator. In order to ensure safety and achieve the function of detonation energy isolation and transmission of the micro-pyrotechnic sequence, ...it is necessary to set up a safety and arming device between the micro-heater and energetic materials on the next level in the initiator. In this paper, the MEMS safety and arming device was simulated and analyzed, and the actuator chip was made based on MEMS technology and then tested. The results showed that the maximum temperature and displacement generated by the silicon-based micro-actuator increased with increasing actuation voltage. When the actuation voltage was larger than 16 V, the device could not work normally because the maximum temperature of the device was higher than the melting point of silicon. Furthermore, the influence factors on the state-recoverable property of the device were studied by changing the actuation voltage, length, width, and thickness of the V-shaped beam in a single way. The results showed that when the actuation voltage remained unchanged and the other factors were changed in a single way, the smaller structural parameters resulted in the shorter response time and recovery time, while the displacement generated was smaller. Meanwhile, the larger structural parameters resulted in larger displacements, while the response time and recovery time were larger. In addition, the state-recoverable characteristics of the device were affected by the working environmental temperature. It is of great significance to the design of the MEMS-based initiator.
Heparan sulfate (HS) is a sulfated glycosaminoglycan abundant on the cell surface and in the extracellular matrix and has several biological activities including anticoagulation and ...anti-inflammation. Liver ischemia reperfusion injury is associated with coagulation and inflammatory responses. Here, we synthesized HS oligosaccharides with defined sulfation patterns and show that synthetic anticoagulant HS oligosaccharides limit liver ischemia reperfusion injury in a mouse model. Using a small targeted HS library, we demonstrate that an oligosaccharide that possesses both anticoagulant activity and binding affinity to HMGB1, the inflammatory target, decreases injury greater than oligosaccharides that only bind to HMGB1 or only have anticoagulant activity. HS oligosaccharides may represent a potential new therapeutic option for decreasing liver damage resulting from ischemia reperfusion injury.
Sepsis is a lethal syndrome manifested by an unregulated, overwhelming inflammation from the host in response to infection. Here, we exploit the use of a synthetic heparan sulfate octadecasaccharide ...(18-mer) to protect against sepsis. The 18-mer not only inhibits the pro-inflammatory activity of extracellular histone H3 and high mobility group box 1 (HMGB1), but also elicits the anti-inflammatory effect from apolipoprotein A-I (ApoA-I). We demonstrate that the 18-mer protects against sepsis-related injury and improves survival in cecal ligation and puncture mice and reduces inflammation in an endotoxemia mouse model. The 18-mer neutralizes the cytotoxic histone-3 (H3) through direct interaction with the protein. Furthermore, the 18-mer enlists the actions of ApoA-I to dissociate the complex of HMGB1 and lipopolysaccharide, a toxic complex contributing to cell death and tissue damage in sepsis. Our study provides strong evidence that the 18-mer mitigates inflammatory damage in sepsis by targeting numerous mediators, setting it apart from other potential therapies with a single target.
A facile one-pot microwave-assisted hydrothermal synthesis of rutile TiO2 quadrangular prisms with dominant {110} facets, anatase TiO2 nanorods and square nanoprisms with co-exposed {101}/111 facets, ...anatase TiO2 nanorhombuses with co-exposed {101}/{010} facets, and anatase TiO2 nanospindles with dominant {010} facets were reported through the use of exfoliated porous metatitanic acid nanosheets as a precursor. The nanostructures and the formation reaction mechanism of the obtained rutile and anatase TiO2 nanocrystals from the delaminated nanosheets were investigated. The transformation from the exfoliated metatitanic nanosheets with distorted hexagonal cavities to TiO2 nanocrystals involved a dissolution reaction of the nanosheets, nucleation of the primary TiO68− monomers, and the growth of rutile-type and anatase-type TiO2 nuclei during the microwave-assisted hydrothermal reaction. In addition, the photocatalytic activities of the as-prepared anatase nanocrystals were evaluated through the photocatalytic degradation of typical carcinogenic and mutagenic methyl orange (MO) under UV-light irradiation at a normal temperature and pressure. Furthermore, the dye-sensitized solar cell (DSSC) performance of the synthesized anatase TiO2 nanocrystals with various morphologies and crystal facets was also characterized. The {101}/111-faceted pH2.5-T175 nanocrystal showed the highest photocatalytic and photovoltaic performance compared to the other TiO2 samples, which could be attributed mainly to its minimum particle size and maximum specific surface area.
•Smooth LSFL can be generated on 4H-SiC.•The LSFL is covered by a homogeneous amorphous layer.•The ratio of a-SiC/SiC measured by the Raman spectrum is proportional to the laser power.
The ...laser-induced periodic surface structure (LIPSS) can be induced on the 4H-SiC by femtosecond laser. However, there is some problems exist during the laser process. For example, the debris induced by femtosecond laser ablation dropped on the sample surface. In this study, the femtosecond laser generated the high-spatial-frequency LIPSS (HSFL) on the 4H-SiC surface. The Raman spectrum was used to measure the HSFL, followed by the chemical etching that removed the oxidation layer. The results showed that the Raman intensity of amorphous SiC (a-SiC) is highly correlated to the etching rate of HSFL.
In addition, the high-quality periodic structures were generated on 4H-SiC after the chemical etching process. The period is near the low-spatial-frequency LIPSS (LSFL). Two different morphology of structures is observed by transmission electron microscope (TEM). One is no ablation region, and the other region exists a little ablation with ablation depth around 30–50 nm. These two regions are similar to the energy distribution of the surface plasmon polariton.
The NiCr igniter is a key element of MEMS-based electro-explosive device (mEED), while electrostatic discharge (ESD) may excite the igniter accidentally. To protect the NiCr igniter from damage by ...ESD, a novel NiCr igniter by integrating the igniter onto a TVS diode based substrate was designed and fabricated through semiconductor technology. The microscope photograph, resistivity, breakdown voltage, firing performance, and ESD protection ability were tested. The results show that the surface of the chip is smooth, the edges of key structures are clear, and there are no major scratches, cracks, and other phenomena on the whole device. The resistivity of all the TVS-mNiCr igniters is between 5 and 7 Ω, and the TVS diode resistance value is normal. The breakdown voltages of the eight types of TVS diodes with different structures are all between 3.5 and 5 V, and the TVS-mNiCr igniters can fire reliably at a constant current of 2 A. After the ESD test, the microscope of the igniter does not change significantly, meaning that the TVS-mNiCr igniter chip has a certain ability of ESD protection. It is of vital importance to guide the design of electrostatic tolerant ability for the MEMS-based electro-explosive device.
PDF
