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In this study, a 4 bit, 10 giga-samples-per-second analog-to-digital converter (ADC) printed circuit board assembly (PCBA) was designed, manufactured, and characterized for digitizing radio telescopes. For this purpose, an Adsantec ANST7120A-KMA flash ADC chip was used. Together with the field-programmable gate array platform, developed by the Collaboration for Astronomy Signal Processing and Electronics Research community, the PCBA enables data acquisition with a wide bandwidth and simplifies the intermediate frequency section. In the current version, the PCBA and the chip exhibit an analog bandwidth of 10 GHz (3 dB loss) and 20 GHz, respectively, which facilitates second, third, and even fourth Nyquist sampling. The following average performance parameters were obtained from the first and second Nyquist zones of the three boards: a spurious-free dynamic range of 31.35/30.45 dB, a signal-to-noise and distortion ratio of 22.95/21.83 dB, and an effective number of bits of 3.65/3.43, respectively. [ABSTRACT FROM AUTHOR]

A ruthenium complex [Ru(phen) 2 (phen-5-amine)-C14] (Ru-C14) with broad-spectrum antibacterial activity was designed and synthesized; positively charged Ru-C14 could target bacteria via electrostatic interactions and showed high binding effectiveness to cell membranes. In addition, Ru-C14 could act as a photosensitizer. Under 465 nm light irradiation, Ru-C14 could generate 1 O 2 , thus disrupting the bacterial intracellular redox balance and leading to bacterial death. Ru-C14 also exhibited minimum inhibitory concentration values of 6.25 μM against Escherichia coli and 3.125 μM against Staphylococcus aureus ; these values are lower than those of streptomycin and methicillin. This work combined the merits of cell membrane targeting and photodynamic therapy for antibacterial activity. The findings might open up a new avenue for effective anti-infection treatment and other medical applications.

In order to understand the composition and accumulation characteristics of phthalates esters (PAEs) in agricultural soils in Gansu province, a total of 41 soil samples from four agricultural soils in Gansu province were collected, and the content of six PAEs compounds was analyzed using a gas chromatography-single quadrupole mass spectrometer (GC-MS). The results showed that the average value of PAEs compounds in agricultural soils in Gansu province was 432.4 μg·kg -1 . The detection rates of DMP, DEP, DnBP, DEHP, and DNOP in the soil were 100%, and BBP was not detected. The order of the average value of PAEs content in the four agricultural soils in Gansu province was:greenhouse>farmland (open field)>forest>grassland. The exceeding rates of dibutyl phthalate (DnBP), dimethyl phthalate (DMP), and dimethyl phthalate (DEP) were 94%, 28%, and 27%, and the remaining three did not exceed the standard. The composition of PAEs in different agricultural soils was different due to their different sources. DEHP and DnBP components in the six different PAEs monomers accounted for a higher proportion and were the main pollutants of PAEs in agricultural soils in Gansu province. In this study, the contents of soil PAEs and DEHP were significantly positively correlated with the residual amount of mulch film in the farmland ( P <0.05). In general, the content of soil PAEs in the Hexi area of Gansu province was significantly higher than that in the Longdong area.

Peripheral nerve injuries represent a significant problem in public health, constituting 2-5% of all trauma cases 1 . For severe nerve injuries, even advanced forms of clinical intervention often lead to incomplete and unsatisfactory motor and/or sensory function 2 . Numerous studies report the potential of pharmacological approaches (for example, growth factors, immunosuppressants) to accelerate and enhance nerve regeneration in rodent models 3-10 . Unfortunately, few have had a positive impact in clinical practice. Direct intraoperative electrical stimulation of injured nerve tissue proximal to the site of repair has been demonstrated to enhance and accelerate functional recovery 11,12 , suggesting a novel nonpharmacological, bioelectric form of therapy that could complement existing surgical approaches. A significant limitation of this technique is that existing protocols are constrained to intraoperative use and limited therapeutic benefits 13 . Herein we introduce (i) a platform for wireless, programmable electrical peripheral nerve stimulation, built with a collection of circuit elements and substrates that are entirely bioresorbable and biocompatible, and (ii) the first reported demonstration of enhanced neuroregeneration and functional recovery in rodent models as a result of multiple episodes of electrical stimulation of injured nervous tissue.

In this study, effects of the thickness of a low temperature (LT) buffer and impurity incorporation on the characteristics of Nitrogen (N)-polar GaN are investigated. By using either a nitridation or thermal annealing step before the deposition of a LT buffer, three N-polar GaN samples with different thicknesses of LT buffer and different impurity incorporations are prepared. It is found that the sample with the thinnest LT buffer and a nitridation step proves to be the best in terms of a fewer impurity incorporations, strong PL intensity, fast mobility, small biaxial strain, and smooth surface. As the temperature increases at ~10 K, the apparent donor-acceptor-pair band is responsible for the decreasing integral intensity of the band-to-band emission peak. In addition, the thermal annealing of the sapphire substrates may cause more impurity incorporation around the HT-GaN/LT-GaN/sapphire interfacial regions, which in turn may result in a lower carrier mobility, larger biaxial strain, larger bandgap shift, and stronger yellow luminescence. By using a nitridation step, both a thinner LT buffer and less impurity incorporation are beneficial to obtaining a high quality N-polar GaN.

Aim: To expresse the Chlamydia pneumoniae Cpn0810 in E.coli BL21, and to study weather could it inducing proinflamatory cytokines including TNF-α and IL-6 in human monocytic (THP-1) and cell apoptosis., Methods: Polymerase chain reaction(PCR) was used to amplify the Cpn0810 gene, PCR products were purified and cloned into the prokaryotic expression vector pGEX6p-2. The restriction plasmids pGEX6p-2/Cpn0810 confirmed by PCR and sequencing was transformed into E.coli BL21. The recombinant protein was purified with glutathione S-transferase (GST) resin chromatography of Novagen after renaturation. THP-1 cells were stimulated by different concentrations of Cpn0810 and for various durations to test the production and the expression of TNF-α and IL-6 by ELISA. Cell apoptosis was detected in C.pneumoniae Cpn0810 cells by Hoechst33258 fluorescence staining and Cell apoptosis was detected in THP-1 cells by Annexin-V-FITC-propidiu-m iodide (PI) staining., Results: The restriction enzymes cleavage analysis and nucleotide sequencing showed the target gene was successfully inserted into pGEX6p-2 prokaryotic expression vector. Cpn0810 stimulated THP-1 cell to produce proinflamatory cytokines including TNF-α and IL-6 in a dose and time-dependent manner. After THP-1 cells were treated with 10 mg/L Cpn0810 for 24 h, apoptosis with nuclear chromatin fragmentation as well as cell shrinkage was observed by fluorescent staining and microscopy; apoptosis of cell was detected after 24 h in THP-1 cells treated with Cpn0810., Conclusion: Cpn0810 recombinant protein could stimulate THP-1 cell to produce and express proinflamatory cytokines including TNF-α and IL-6; After THP-1 cells were treated with 10 mg/L Cpn0810 for 24 h, apoptosis of cell was detected after 24 h in THP-1 cells treated with Cpn0810.