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In this study, we adopted a simple strategy of the arc discharge to prepare the B-doped SiC microwave nano-absorbers. Herein, the amorphous boron was selected as a doping B element source to tune the electromagnetic parameters of the SiC nanopowders. The experimental results indicate that the doping B in the SiC can conveniently tailor the microwave absorption capability of the SiC nanopowders. The appropriate doping B in the SiC can contribute to excellent synergistic effects among its defect dipoles, leakage, and magnetism. Among the doped SiC with B doping content of 0, 5, 10, and 15 at.%, the SiC with doping B content of 10 at.% acquired the optimized impedance matching and enhanced microwave absorption properties. And the optimal reflection loss (RL) value − 51.2 dB at 6.76 GHz with a matching thickness of 2.9 mm is acquired. The RL of the B-doped SiC nanopowders with B doping content of 10 at.% exceeding − 10 dB is about 3–5 times those of the other three samples in the ranges of 1–18 GHz at a matching thickness of 1.2–6.0 mm. Therefore, this work provided a feasible way to tune the microwave absorption properties of the B-doped SiC, which is of great significance to improve SiC-based high-temperature dielectric ceramics of microwave absorption performances by the defect-engineering strategy.

Kynurenine pathway is critically important to catabolize tryptophan, to produce eye chromes, and to protect nervous system in insects. However, several issues related to tryptophan degradation remain to be clarified. In the present paper, we identified three genes (karmoisin, vermilion and cardinal) involved in kynurenine pathway in Henosepilachna vigintioctopunctata. The karmoisin and cardinal were highly expressed in the pupae and adults having compound eyes. Consistently, high-performance liquid chromatography result showed that three ommochrome peaks were present in adult heads rather than bodies (thoraces, legs, wings and abdomens). RNA interference (RNAi)-aided knockdown of vermilion caused accumulation of tryptophan in both adult heads and bodies, disappearance of ommochromes in the heads and a complete loss of eye color in both pupae and adults. Depletion of cardinal brought about excess of 3-hydroxykynurenine and insufficient ommochromes in the heads and decolored eyes. RNAi of karmoisin resulted in a decrease in ommochromes in the heads, and a partial loss of eye color. Moreover, a portion of karmoisin-, vermilion- or cardinal-silenced adults exhibited negative phototaxis, whereas control beetles showed positive phototaxis. Furthermore, dysfunctions of tryptophan catabolism impaired climbing ability. Our findings clearly illustrated several issues related to kynurenine pathway and provided a new insight into the physiological importance of tryptophan catabolism in H. vigintioctopunctata.

Background Soil salinization is a threat to food security. China is rich in saline land resources for potential and current utilization. The cultivation and promotion of salt-tolerant rice varieties can greatly improve the utilization of this saline land. The super hybrid rice Chaoyouqianhao (CY1000) is one of the most salt-tolerant rice varieties and is widely used, but the molecular mechanism underlying its salt tolerance is not clear. Results In this study, the characteristics of CY1000 and its parents were evaluated in the field and laboratory. The results showed that aboveground parts of CY1000 were barely influenced by salt stress, while the roots were less affected than those of its parents. A comparative transcriptomic strategy was used to analyze the differences in the response to salt stress among the male and female parents of CY1000 at the seedling stage and the model indica rice 93–11. We found that the salt tolerance of CY1000 was mainly inherited from its male parent R900, and its female parent GX24S showed hardly any salt tolerance. To adapt to salt stress, CY1000 and R900 upregulated the expression of genes associated with soluble component synthesis and cell wall synthesis and other related genes and downregulated the expression of most genes related to growth material acquisition and consumption. In CY1000 and R900, the expression of genes encoding some novel key proteins in the ubiquitination pathway was significantly upregulated. After treatment with MG-132, the salt tolerance of CY1000 and R900 was significantly decreased and was almost the same as that of the wild type after salt stress treatment, indicating that ubiquitination played an important role in the salt tolerance mechanism of CY1000. At the same time, we found that some transcription factors were also involved in the salt stress response, with some transcription factors responding only in hybrid CY1000, suggesting that salt tolerance heterosis might be regulated by transcription factors in rice. Conclusion Our results revealed that the ubiquitination pathway is important for salt tolerance in rice, and several novel candidate genes were identified to reveal a novel salt tolerance regulation network. Additionally, our work will help clarify the mechanism of heterosis in rice. Further exploration of the molecular mechanism underlying the salt tolerance of CY1000 can provide a theoretical basis for breeding new salt-tolerant rice varieties.

Here, a facile one-step arc-discharge method was applied to synthesize the Al-doped SiC nanoparticles. Compared to undoped SiC, the shifts of bound-hole around AlSi defects in the Al-doped SiC crystal at the alternating electromagnetic field from one equilibrium position to another must overcome a potential barrier, producing forceful relaxation polarization. Meanwhile, the abundant defects caused by Al doping in Al-doped SiC nanoparticles not only act as polarization centers contributing to the enhanced polarization loss but also create more current carriers increasing the leakage loss. Furthermore, the weak magnetism caused by the AlSi defects can further optimize the balance of dielectric loss and magnetic loss and achieve a better impedance matching for Al-doped SiC nanoparticles. Therefore, Al-doped SiC nanoparticles have the enhanced microwave absorption capacity, which exhibits the minimum reflection loss (RL) value of − 43.7 dB at a thickness of 3 mm and RL below − 10 dB covered 3.2–18 GHz with the changeable thickness of 1.22–5.5 mm. This work provided a defect-engineering strategy in modifying SiC-based high-temperature dielectric ceramics of microwave absorption performances.

We adopted a facile method consisting of the arc discharge method combined with the in situ self-polymerization process to synthesize the cubic TiN@CN nanocapsules in this work, and we also investigated the electrochemical performance and microwave absorption properties of the TiN@CN nanocapsules in detail. The results show that the TiN@CN nanocapsules exhibit excellent electrochemical performance. The specific capacitance of the TiN@CN nanocapsules is 119 F g−1 at 1 A g−1, and their capacitance retention rate is 92% after 5000 cycles at the current density of 2 A g −1. Besides, the cubic TiN@CN nanocapsules also exhibit powerful microwave absorption capacity. The reflection loss (RL) below − 20 dB is achieved in a wide frequency range of 7.2–15.5 GHz with a thickness range of 1.1–2.3 mm, and the optimal RL value is − 40.6 dB at 10.6 GHz with a relatively thin thickness of 1.6 mm. Therefore, TiN@CN nanocapsules are promising and applicable as electrode materials for supercapacitors and as microwave absorbers.

The pore structure of coke under CO2 atmosphere was investigated by the carbon solution-loss reaction experiment. The results show that the pore size distribution of coke gradually changes from dispersion to relative concentration with the increase in carbon loss rate, but it tends to be dispersed again in the late stage of the reaction, and the pore volume and specific surface area also increase first and then decrease with the increase in carbon loss rate. Scanning electron microscopy results show that the evolution of coke pores is from the formation of micropores to the expansion of micropores, and finally the micropore and mesopores collapse to form a large number of string holes. The chemical bonds and functional groups of different reacted cokes were analyzed by Fourier-transform infrared spectroscopy. Furthermore, the microstructure of reacted cokes was analyzed by optical microscopy, and then the ordering of the affinity of different microstructures with CO2 was given. The volume hypothesis which was the theory about energy size of comminution was adopted to analyze the degradation behavior of reacted cokes. The breakage energy of reacted cokes was calculated by volume hypothesis, and the power consumption coefficient CK of different reacted cokes was determined by drum experiment, and then the degradation behavior of reacted cokes under different power consumptions was predicted.

MicroRNAs (miRNAs), a series of small noncoding RNAs that regulate gene expression at the post-transcriptional/translational level, are pivotal in cell differentiation, biological development, occurrence, and development of diseases, especially in cancers. Early studies have shown that miRNA-335 (miR-335) is widely dysregulated in human cancers and play critical roles in tumorigenesis and tumor progression. In this review, we aim to summarize the regulation of miR-335 expression mechanisms in cancers. We focus on the target genes regulated by miR-335 and its downstream signaling pathways involved in the biological effects of tumor growth, invasion, and metastasis both in vitro and in vivo, and analyze the relationships between miR-335 expression and the clinical characteristics of tumors as well as its effects on prognosis. The collected evidences support the potential use of miR-335 in prognosis and diagnosis as well as the therapeutic prospects of miR-335 in cancers.

The high resistant rate of Adriamycin (Adr) is associated with a poor prognosis of breast cancer in women worldwide. Since miR-222 might contribute to chemoresistance in many cancer types, in this study, we aimed to investigate its efficacy in breast cancer through PTEN/Akt/p27 kip1 pathway. Firstly, in vivo, we verified that miR-222 was upregulated in chemoresistant tissues after surgery compared with the paired preneoadjuvant samples of 21 breast cancer patients. Then, human breast cancer Adr-resistant cell line (MCF-7/Adr) was constructed to validate the pathway from the parental sensitive cell line (MCF-7/S). MCF-7/Adr and MCF-7/S were transfected with miR-222 mimics, miR-222 inhibitors, or their negative controls, respectively. The results showed that inhibition of miR-222 in MCF-7/Adr significantly increased the expressions of PTEN and p27 kip1 and decreased phospho-Akt (p-Akt) both in mRNA and protein levels (p < 0.05) by using quantitative real-time PCR (qRT-PCR) and western blot. MTT and flow cytometry suggested that lower expressed miR-222 enhanced apoptosis and decreased the IC50 of MCF-7/Adr cells. Additionally, immunofluorescence demonstrated that the subcellular location of p27 kip1 was dislocated resulting from the alteration of miR-222. Conversely, in MCF-7/S transfected with miR-222 mimics, upregulation of miR-222 is associated with decreasing PTEN and p27 kip1 and increasing Akt accompanied by less apoptosis and higher IC50. Importantly, Adr resistance induced by miR-222 overexpression through PTEN/Akt/p27 was completely blocked by LY294002, an Akt inhibitor. Taken together, these data firstly elucidated that miR-222 could reduce the sensitivity of breast cancer cells to Adr through PTEN/Akt/p27 kip1 signaling pathway, which provided a potential target to increase the sensitivity to Adr in breast cancer treatment and further improved the prognosis of breast cancer patients.

In this study, the supercritical fluid pretreatment technology was employed to complete the electroless plating and the wool fabrics plated with copper were prepared via electroless plating. Through the oxidation---reduction reactions, the copper deposited and formed a heterogeneous metal layer on the wool fiber surfaces. Some technique such as SEM was employed to characterize the distribution state of the copper layer staying on the wool fiber surfaces. The shielding property of the wool fabrics plated with copper was examined. It was experimentally proved that the wool fabrics plated with copper exhibited good anti-static and anti-UV properties as well as high durability.

Emerging studies suggest that endovascular treatment (EVT) may be superior to intravenous thrombolysis for acute ischemic stroke (AIS). We performed a systematic review and meta-analysis of all randomized controlled trials (RCTs) to assess the efficacy and safety of endovascular treatment in patients with acute ischemic stroke as compared with intravenous thrombolysis. We assessed RCTs investigating EVT versus intravenous thrombolysis (IVT) published up to June 2015. In total, 21 studies of 4473 patients were included in the systematic review and meta-analysis. EVT significantly improved functional outcome at 90 days (risk ratio (RR) 1.35, 95 % confidence interval (CI) 1.18 to 1.55, I 2 = 61 %) and reduced the mortality (RR 0.81, 95 % CI 0.68 to 0.95, I 2 = 0 %), with similar symptomatic hemorrhagic transformation (SHT) rate (RR 1.12, 95 % CI 0.88 to 1.44, I 2 = 0 %). Based on the current data, endovascular therapy may produce good clinical outcomes with similar symptomatic hemorrhage and mortality as compared with intravenous thrombolysis in acute ischemic stroke. This advancing intervention is a landmark change in stroke treatment and could be of huge potential benefit to patients worldwide.

The technologies for producing twinning induced plasticity (TWIP) blank in large scale with argon oxygen refining (AOD)-ingot casting-electroslag remelting (ESR) processes were studied. It was found that it was difficult to refine the low carbon Fe-25Mn-3Al-3Si TWIP steel using hot metal of high Mn content in AOD refining by a technology of decarburization and manganese retaining. However, it is practicable to perform decarburization and manganese retaining with the hot metal of lower Mn content in the early stage of AOD refining and do alloying with electrolytic manganese in the late stage. To overcome the problem of castability of TWIP steel, high superheat casting process was applied in ingot casting process, and the solidification structure of TWIP ingot was not compact and even, mainly composed of rough and long columnar and central random oriental dendrite. Due to the Ar protection and low current remelting processes applied in ESR procedure, the solidification structure was significantly improved and the inclusions were well controlled after ESR.

Lead-free solution-processed solid-state photovoltaic devices based on formamidinium tin triiodide (FASnI3) and cesium tin triiodide (CsSnI3) perovskite semiconductor as the light harvester are reported. In this letter, we used solvent engineering and anti-solvent dripping method to fabricate perovskite films. SnCl2 was used as an inhibitor of Sn4+ in FASnI3 precursor solution. We obtained the best films under the function of toluene or chlorobenzene in anti-solvent dripping method and monitored the oxidation of FASnI3 films in air. We chose SnF2 as an additive of CsSnI3 precursor solution to prevent the oxidation of the Sn2+, improving the stability of CsSnI3. The experimental results we obtained can pave the way for lead-free tin-based perovskite solar cells (PSCs).

A series of N-hydroxytriazole-4-carboxamide derivatives were synthesized, and their potential HIV integrase inhibitory activities were evaluated.

The authors of the present paper evaluated the sliding wear behaviors of epoxy and its composites filled with untreated and treated SiC nanoparticles. The experimental results indicate that the nanoparticles pretreated by graft polymerization of polyacrylamide effectively improved the overall performance of the matrix epoxy. In comparison with the untreated SiC nanoparticles, the grafted SiC nanoparticles led to more significant reduction in frictional coefficient and wear rate of epoxy. Even under high contact pressure, the composites with grafted SiC nanoparticles possessed the highest wear resistance. The strong interfacial bonding between the grafted SiC nanoparticles and the matrix should account for the properties enhancement. Accordingly, a feasible way of efficiently applying SiC nanoparticles to the preparation of wear resisting nanocomposites has been developed.

Nano-sized Al2O3 particles grafted with polystyrene or polyarcrylamide were employed as fillers for fabricating epoxy based composites. Curing habit, mechanical properties and tribological performance revealed by sliding wear tests of the composites were investigated. The experimental results indicated that the nanoparticles accelerate curing of epoxy, increase composites' impact strength and decrease wear rate and frictional coefficient of the composites. The surface modification by means of grafting polymerization can further enhance the properties improvement of epoxy due to the increased filler/matrix interfacial interaction. Compared to frictional coefficient, wear rate of epoxy can be decreased more remarkably by the addition of nano-alumina when rubbing against steel. The wear mode changes from severe peeling off of unfilled epoxy to mild micro-ploughing in the case of nano-alumina filled composites.

Background Ectopic TSH-secreting pituitary adenoma (TSH-oma) is a very unusual disorder. To date, there are only four cases reported. It is difficult to distinguish ectopic cases from both regular TSH-omas and resistance to thyroid hormone (RTH). Case presentation A newly identified case of ectopic TSH-oma arising from the nasal pharynx was described, and reports of four prior cases were reviewed. The patient was a 41-year-old male who developed what appeared to be typical hyperthyroidism and atrial fibrillation in 2009. Thyroid function tests showed elevated basal levels of free T3 (FT3, 24.08 pmol/L), free T4 (FT4, 75.73 pmol/L), and serum TSH (7.26 μIU/ml). Both TSH-oma and resistance to thyroid hormone syndrome were considered. TRH stimulating test was negative, whereas octreotide inhibition test showed a reduction in TSH by 30.8%. Furthermore, a large space-occupying lesion located at the nasopharynx was found by computed tomography and magnetic resonance imaging (MRI). A normal pituitary was visualized. Ectopic TSH-oma was preliminarily established. Using an endoscopic endonasal approach, the tumor was resected. Histological features and immunophenotypes were consistent with those of TSH-secreting tumor. The levels of both free thyroxine and TSH returned to normal ranges the day after surgery and remained within normal range for 48 months. Conclusions Although exceedingly rare, ectopic TSH-oma should be considered for patients with inappropriate secretion of TSH with hyperthyroidism and pituitary tumor undetectable by computed tomography and MRI. To our knowledge, this is the first case followed up more than 4 years. The characteristics and successful interventions summarized in this report provide a guideline for clinicians.

A new family of chloride transport proteins has recently emerged. These proteins have extensive homology to a protein previously isolated from bovine tracheal epithelium that acts as a Ca(2+)-sensitive Cl(-) channel (CaCC) when heterologously expressed or when reconstituted into planar lipid bilayers. Several new members of this family have been identified in human, murine, and bovine epithelia, in addition to some other tissues, and are associated with Ca(2+)-sensitive conductive chloride transport when heterologously expressed in Xenopus oocytes or HEK 293 cells. The expressed current is also sensitive to inhibitors such as DIDS and niflumic acid. In addition, at least one family member acts as an endothelial cell adhesion molecule. This emerging family may underlie the Ca(2+)-mediated Cl(-) conductance responsible for rescue of the cystic fibrosis (CF) knockout mouse from significant airway disease.

To date, reinforcement learning has mostly been studied solving simple learning tasks. Reinforcement learning methods that have been studied so far typically converge slowly. The purpose of this work is thus two-fold: 1) to investigate the utility of reinforcement learning in solving much more complicated learning tasks than previously studied, and 2) to investigate methods that will speed up reinforcement learning. This paper compares eight reinforcement learning frameworks: adaptive heuristic critic (AHC) learning due to Sutton, Q-learning due to Watkins, and three extensions to both basic methods for speeding up learning. The three extensions are experience replay, learning action models for planning, and teaching. The frameworks were investigated using connectionism as an approach to generalization. To evaluate the performance of different frameworks, a dynamic environment was used as a testbed. The environment is moderately complex and nondeterministic. This paper describes these frameworks and algorithms in detail and presents empirical evaluation of the frameworks.