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We propose a low-cost programmable metasurface (PM) with distinct advantages of being 1 bit or quasi-2 bit, featuring dual polarization, and requiring fewer I/O pins. This design merges the control circuit and the microwave structure layout on a thin, single-layer printed circuit board (PCB). To achieve this, we transform the aperiodic control circuit into a periodic circuit by loading D flip-flops, which is further simplified by loading controlled current sources (CCSs). Based on the layout of the bias lines, a capacitive slot is added to form the microwave structure. Two PIN diodes are orthogonally surface-mounted to achieve dual-polarization characteristics. In unit arraying, D flip-flops are staggered to reduce I/O pins usage. The design can be easily extended to quasi-2 bit by stacking the PCBs. A $16\times16\,\,1$ -bit PM is simulated, fabricated, and measured to verify this design. The simulation includes functions such as generating high-gain beams, multibeams, and electromagnetic (EM) waves carrying orbital angular momentum (OAM). The far-field patterns exhibited a ±60° scanning range, achieving a maximum aperture efficiency of 25%. This design introduces a simple, cost-effective, adjustable operating frequency, dual-polarization, 1-bit, or quasi-2-bit PM, with potential applications in communication, imaging, and sensing scenarios.

A low-cost single-layer 2-bit programmable metasurface (PM) is proposed in this article. This PM is processed on a single-layer printed circuit board (PCB) with the microwave structure, ground, and bias lines, enabled by a folded ground. The folded ground design moves a part of the ground from the bottom to the top layer to leave an area for bias lines. Vias are used to connect the ground in top and bottom layers to form a whole. The bias line in the microwave structure area is grounded by two capacitances to isolate microwave current with the bias line area. An asymmetric patch is designed in microwave area as the 2-bit microwave structure. To verify the microwave performance of this PM, functions of generating double beams, electromagnetic (EM) waves with orbital angular momentum (OAM), and a high gain beam are simulated. The far-field pattern of a $16\times16$ PM antenna in beam scanning is measured. The measured results show that the PM antenna has a beam scanning capability of ±60° and a maximum aperture efficiency of 44.6%. Finally, to illustrate the universality of the folded ground design, the varactor-loaded continuous phase adjustable PM and variable polarization 1-bit PM are discussed.

The purpose is to improve the treatment effect on the antibiotics in the wastewater of livestock farms. The antibiotic wastewater from a livestock farm is taken as the research object. The wastewater from the livestock farm is sampled and analyzed through batch anaerobic biochemical degradation experiment and direct aerobic biochemical degradation experiment. Also, an anaerobic and aerobic biochemical test device is constructed in the laboratory to study the removal effect on the antibiotics in the wastewater based on anaerobic biochemical degradation and aerobic biochemical degradation technologies. The results show that the removal rate of antibiotics in the wastewater of the livestock farm by anaerobic biochemical degradation technology is only about 25%. The main reason is that sulfa mono methoxine (SMM) is difficult to be degraded by anaerobic degradation technology, and its concentration in the wastewater is more than 95%. And the degradation effect of anaerobic biochemical treatment on sulfonamide antibiotics is far less than that on lactam antibiotics. When the concentrates of sulfadiazine (SD), sulfamethoxazole (SMX), sulfamethazine (SMZ), and SMM (sulfamonomethoxypyrimidine) in the wastewater are high, the degradation effect of anaerobic sludge on the four is SMX > SD > SMZ > SMM. In the direct aerobic biochemical treatment, aerobic sludge has good degradation ability for sulfonamides and β-lactam antibiotics, and the overall removal rate of antibiotics in the wastewater can reach more than 80%. When the concentrates of SD, SMX, SMZ, and SMM in the wastewater are high, the degradation effect of aerobic sludge on the above four antibiotics in the direct aerobic treatment is SD > SMX > SMZ > SMM.

AbstractIn this study, modified polyvinyl alcohol (PVA) was prepared and characterized by element analysis, scanning electron microscopy, Fourier transform infrared spectroscopy, and surface area and proximity analysis. The isotherms and thermodynamic parameters of the modified PVA adsorption process were estimated. The data indicate that the adsorption process is exothermic, feasible, spontaneous, and fit to the Langmuir isotherm model. The maximum adsorption capacities for Cd(II) and Pb(II) were calculated to be 1.19 and 1.48 mmol/g, respectively. Sorption was rapid, with the removal percentage higher than 98% after 10 min. Adsorption behavior mechanisms were analyzed using pseudo-first-order and pseudo-second-order models, which were highly fitted to pseudo-second-order model. This suggests the main adsorption mechanism is a chemical adsorption, involving ion exchange and valence forces through sharing or exchange of electrons between metal ions and modified PVA. The modified PVA is a good reusable sorbent, enhancing the economics of practical application for the removal of Cd(II) and Pb(II) from water and wastewater.

AbstractSteam distillation (SD) and solvent extraction (SE) using hexane, methylene chloride, and ethyl acetate were compared for their effectiveness in the oil extraction from Rehmannia glutinosaLibosch. The four oil samples extracted by both methods respectively were analyzed using GC-MS. The qualitative comparison showed that the number and total amount of compounds detected in hexane was higher than others. More high-volatile compounds were detected in SD extract than in SE extract. The first principal component separated the SD extract from other three SE samples based on the higher concentrations of high-volatile compounds.

Four novel polyketides, named pestalpolyols A (1), B (2), C (3), and D (4), were isolated from solid fermentation products of Pestalotiopsis sp. cr013. Their structures were elucidated by extensive spectroscopic methods, including 1D and 2D nuclear magnetic resonance and high-resolution electrospray ionization mass spectrometry experiments, and the absolute configuration was confirmed by single-crystal X‑ray diffraction analysis using the anomalous scattering of Cu Kα radiation. The inhibitory activities of compounds 1, 2, and 4 against five human tumor lines were tested in vitro, and showed IC50 values 2.3- 31.2 μM. [ABSTRACT FROM AUTHOR]

AbstractThe essential oil was isolated using the ultrasound method from the root of Rehmannia glutinosaLibosch root with a yield of 0.47 % (w/w) by orthogonal matrix method. This yield of essential oil with steam distillation after the ultrasound method (EOU) is 2.03 times than that without ultrasound-assisted isolation (EO). The essential oil samples with and without the ultrasound method were analyzed by GC-MS. Total forty-six components in EOU were identified. The major compounds in the EOU and EO were found to be identical namely methyl palmitate, ethyl oleate, furfural, and methyl linoleate. Antioxidant activity of the samples were determined by two different test systems namely hydroxyl radical scavenging activity assay and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity assay. EOU showed higher antioxidant properties than EO, probably due to their different compositions.

AbstractIn this study, cellulase and pectinase were applied to extract the essential oil from Chrysanthemum morifoliumRamat. The extraction conditions were optimized by response surface methods. Under the optimal conditions as solid-liquid ratio of 9:1, enzyme dosage 4.4 %, extraction time 5 h, the highest extraction yield of essential oil was 0.848 %. The essential oil was analyzed by GC-MS and 84 volatile compounds, accounting for 43.9 % of the oil, were identified and the main components were β-Sesquiphellandrene, β-selinene, (E)-β-farnesene, (Z)-β-farnesene and α-curcumene. The oil was applied to tobacco flavoring with different concentration and the sensory evaluation showed that at the dosage of 1 % (g/g). The results showed that irritation was reduced and sweet aroma was increased in the smoke. Therefore, Chrysanthemumoil could be considered as an ideal natural tobacco flavor.

Hospital network office automation system could make the hospital connected by a PC, terminal equipment, medical equipment and hospital networks to link up and connected to the Internet. In this paper, the star tree on the hospital's existing network structure transformation, using port aggregation technology upgrades to existing network data transmission and improve the operating efficiency of the entire hospital network, and the hospital server, computer workstation security configuration and remote management configuration, database and application development of all types of information systems are a good network support.

In this paper, a highly sensitive and portable mercury(ii) ion sensor based on personal glucose meter (PGM) recording is proposed. Thymine–thymine mismatches in the capture and detection of DNA were used to recognize target Hg2+. Magnetic separation and hydrolysis of sucrose into glucose of DNA-invertase conjugation were employed to obtain the PGM signal. There was a linear relationship between the PGM signal and the concentration of Hg2+in the range of 8.0 nM to 1 μM. A correlation coefficient of 0.995 was obtained and the relative standard deviation was 3.6% for a concentration of 100 nM Hg2+(n= 9). The selectivity and performance of the Hg2+sensor in lake water, tap water and river water were also studied, which suggested our method has a great potential to be used in real applications.

n 3D image processing, such as medical volume data and industrial CT volume data analysis, speckle noise suppressing significantly affects their accuracy. This paper utilizes a group of volume morphology arithmetic operators, mainly including volume open and volume close, by extending area morphology into 3-D space. Using these operators, the light and dark objects of small size could be removed directly from the 3-D space of the target objects, while the connectivity of the main 3-D target objects in the volume data is still preserved. To improve the volume morphology operations efficiency, we decompose volume data in bitplanes instead of in gray scale space to reduce the binary volumes. To verify the effect of the improved volume morphology operators, they are applied to suppress speckle noises in 3-D images of coral and rat skull and compared with original volume morphology operations. Experimental results show that the algorithm proposed in this paper can significantly reduce computing time, while maintaining comparable results to original operations results.

In clinical practice, prolonged occlusion of main arteries causes accumulation of metabolic waste and lactate. Reperfusion of blood flow is usually accompanied by circulatory shock. This study investigates the molecular mechanisms responsible for acidosis-induced hypotension and proposes therapeutic strategies for improving hemodynamic stability following ischemia-reperfusion acidosis. Vasomotor function of aortic rings was studied after cumulative addition of HCl in organ chambers (pH 7.4–7.0). Cultured vascular smooth muscle cells (VSMCs) were exposed to acidic buffer, and intracellular Ca2levels were determined with Fluo3-AM. In an in vivoexperiment, rat aorta was cross-clamped for 45 min and followed by declamping. Hemodynamic changes were measured in the presence and absence of an ATP-sensitive Kchannel (KATPchannel) antagonist PNU37883A (3 mgkg). Acidosis induced vasorelaxation in a dose-dependent manner, which was significantly attenuated by a KATPantagonist glibenclamide. Inhibition of KATPchannel increased intracellular Ca2load in the cultured VSMCs. Pretreatment with PNU37883A significantly attenuated systemic hypotension following reperfusion. However, systemic antagonism of KATPchannel significantly increased the overall mortality. Recording of electrocardiogram showed progressive development of bradyarrhythmia with ST-segment elevation in animals pretreated with PNU37883A before reperfusion. We demonstrate that acidosis-induced vasodilation is, in part, mediated by the activation of KATPchannels through reduction of intracellular Ca2in VSMCs. However, systemic antagonism of KATPchannel significantly increases the overall mortality secondary to the development of cardiac dysrhythmia in animals with profound experimental metabolic acidosis, suggesting that activation of KATPchannel is a protective response during reperfusion acidosis.

This paper aims at research on fundamental principles of long concrete wall cracks in basement on the basis of series basic experiments and engineering practices. Relying on typical project, we use ABAQUS finite element analysis software to conduct simulation analysis to provide evidence for integrated control of cracks. Simulation analysis results show that the reinforcement stresses has tight connections with constraint mode of structure, for instance, column side and the location connected with foundation; effective limits of boundary constraints to structure deformation and constraints of free-form deformation on long wall structure make the concentration of reinforcement stresses nearing constraint location relatively obvious; under the effects of temperature and contraction, internal force of concrete wall will be re-distributed, therefore, reinforcement stress of concrete can not directly reveal actual force distribution inside the wall, but the overall trend is close to concentrated pattern of reinforcement stress.

A /modified graphite sphere composite (labeled as ) was prepared by high energy ball milling using nano-Si, Co, Mn, Al, and MGS as precursors. The compositions and morphology of the composite material were characterized by an X-ray diffractometer and scanning electron microscope. Constant current charge-discharge technique and electrochemical impedance spectroscopy were employed to investigate the electrochemical behaviors of . exhibits obviously improved cyclic performance with a high reversible capacity. The first reversible capacity of is , and 91% of the capacity may be maintained after 70 cycles. The improvement of in the electrochemical performance is attributed to the stability of the electrode structure upon cycling.

Retinoid X receptor alpha (RXRalpha) plays a pivotal role in regulating liver metabolism. RXRalpha-mediated gene expression involved in amino acid metabolism was examined using the NIA Mouse 15K cDNA microarray containing 15,000 different expressed sequence tags. Seven amino acid metabolic genes, three of which encode enzymes involved in phase II detoxification process, were identified as RXRalpha target genes in mouse liver. Glutamate-cysteine ligase catalytic subunit (GCLC), glutathione S-transferasemicro, and glutathione peroxidase 1 were down-regulated in the liver of hepatocyte RXRalpha-deficient mice. The down-regulation of GCLC in RXRalpha-deficient mice led to 40% and 45% reductions in the rate of glutathione (GSH) synthesis and level of hepatic GSH, respectively. Primary hepatocytes from RXRalpha-deficient mice were more sensitive to t-butylhydroperoxide-induced oxidative stress. However, GSH diminished RXRalpha-deficient mice were resistant to acetaminophen (APAP)-induced hepatotoxicity. Analysis of phase I detoxification genes revealed that CYP1A2 and CYP3A11 were up-regulated in wild-type mice but down-regulated in RXRalpha-deficient mice after APAP administration. Taken together, the data indicate that RXRalpha centrally regulates both phase I and phase II drug metabolism and detoxification. Regulation of hepatic GSH levels by RXRalpha is essential to protect hepatocytes from oxidative stress, whereas up-regulation of phase I drug metabolism genes by RXRalpha may render the liver more sensitive to APAP-induced toxicity.