ABSTRACT Pneumatic seed metering devices are widely used in high-speed and precise corn seeding operations. The objective of this study was to analysis the high-speed seeding performance of a pneumatic precision seed metering device at seeding speed ≥12 km/h. In this study, full-factor experiments were conducted of an air-suction rotary-hub corn precision seed metering device at the early stage of development. Seed leaking was the primary failure mode, and the experimental factors had no evident regular influence on the repeat index. The negative pressure of 3-7 kPa had significantly positive and negative correlations with the qualified index and the leak index, whereas the seeding speed of 12-20 km/h was significantly negatively and positively correlated with the qualified index and the leak index, respectively. The leak index reached its greatest value of 32.48%, 15.61% and 66.77% when the negative pressure was 3 kPa, and it was always less than 10% when the negative pressure was greater than 6 kPa for the three corn seed varieties. The corn seed varieties with smaller sizes and regular shapes were more suitable for high-speed precision seeding operations above 12 km/h, and the negative pressure could be increased to improve the qualified index and reduce the leak index.

Abstract Gut bacterial β-glucuronidase (GUS) can reactivate xenobiotics that exert enterohepatic circulation- triggered gastrointestinal tract toxicity. GUS inhibitors can alleviate drug-induced enteropathy and improve treatment outcomes. We evaluated the inhibitory effect of Polygonum cuspidatum Siebold & Zucc. and its major constituents against Escherichia coli GUS (EcGUS), and characterized the inhibitory mechanism of each of the components. Trans-resveratrol 4’-O-β-D-glucopyranoside (HZ-1) and (-)-epicatechin gallate (HZ-2) isolated from P. cuspidatum were identified as the key components and potent inhibitors. These two components displayed strong to moderate inhibitory effects on EcGUS, with Ki values of 9.95 and 1.95 μM, respectively. Results from molecular docking indicated that HZ-1 and HZ-2 could interact with the key residues Asp163, Ser360, Ile 363, Glu413, Glu504, and Lys 568 of EcGUS via hydrogen bonding. Our findings demonstrate the inhibitory effect of P. cuspidatum and its two components on EcGUS, which supported the further evaluation and development of P. cuspidatum and its two active components as novel candidates for alleviating drug-induced damage in the mammalian gut.

OBJECTIVES: To introduce a new laparoscopic splenectomy (LS) approach. METHODS: Sixteen patients underwent LS with general anaesthesia and carbon dioxide pneumoperitoneum. The details of the surgery are as follows: 1. The omentum was incised along the greater curvature and retracted as much as possible to expose the pancreatic body and tail. 2. The right arteriovenous root in the gastric omentum was ligated to sufficiently expose the pancreatic body and tail. 3. The pancreatic capsula was opened along the inferior margin of the pancreatic tail, elevated and separated until the superior margin of the pancreas was grasped. The entire splenic pedicle was retracted using a string. The branching blood vessels in the splenic hilus were ligated using clamps and separated. The splenogastric and splenophrenic ligaments were transected proximally using an ultrasonic knife, and the thick short gastric blood vessels were clamped. This procedure allows complete exposure of the area above the pancreatic tail where the splenic hilus is located. The splenoportal vasculature was suspended using a 7-0 silk suture to easily manipulate this tissue. The splenic portal vessels were dissected using an ultrasonic knife, and the portal vessels were isolated individually using vascular clamps and transected. The splenogastric and lienorenal ligaments were also transected. The spleen was then placed into a bag, and the surgical port was slightly enlarged. Finally, the spleen was sectioned for removal. RESULTS: Fifteen surgeries were successfully performed from March 2015 to January 2016. One patient underwent laparotomy. No patients developed postoperative intra-abdominal haemorrhage or infection. One patient developed subcutaneous emphysema, and one developed a wound infection. No deaths occurred. CONCLUSIONS: Active exposure of the area dorsal to the pancreatic tail is a safe and simple splenectomy method.

Flower - like Co(OH)2/C nanocomposites have been synthesized by a facile hydrothermal method. Flower - like Co(OH)2/C nanocomposites were self - assembled by the nanosheets with the thickness distribution of 50 - 80 nm and abundant flocculent carbon structures. With the help of transmission electron microscopy and energy dispersive spectrometer, nanosheets were observed to have core/shell structure, in which Co(OH)2 worked as cores and amorphous C as shells. When the as - prepared products were heated for 6 h at 180 ºC, the Co(OH)2 cores were amorphous. The heating time increased to 10 h, the Co(OH)2 cores became crystalline. The formation mechanism and the self - assembly evolution process were proposed. The microwave dielectric properties of Co(OH)2/C nanocomposites were investigated in the frequency range of 0.03 - 18 GHz. Compared with the amorphous Co(OH)2/C nanocomposites, crystalline nanocomposites had the better conductivity.

DNJ, an inhibitor of α-glucosidase, is used to suppress the elevation of postprandial hyperglycemia. In this study, we focus on screening an appropriate microorganism for performing fermentation to improve DNJ content in mulberry leaf. Results showed that Ganoderma lucidum was selected from 8 species and shown to be the most effective in improvement of DNJ production from mulberry leaves through fermentation. Based on single factor and three factor influence level tests by following the Plackett-Burman design, the optimum extraction yield was analyzed by response surface methodology (RSM). The extracted DNJ was determined by reverse-phase high performance liquid chromatograph equipped with fluorescence detector (HPLC-FD). The results of RSM showed that the optimal condition for mulberry fermentation was defined as pH 6.97, potassium nitrate content 0.81% and inoculums volume 2 mL. The extraction efficiency reached to 0.548% in maximum which is 2.74 fold of those in mulberry leaf.

A new zero-waste and zero-pollution composite adhesive labeled Chinese fir-based adhesive for exterior plywood was synthesized by blending alkaline Chinese fir (Cunninghamia lanceolata) liquid with a small amount of phenol-formaldehyde (PF). The free phenol and free formaldehyde content of the Chinese fir-based adhesive were sharply decreased compared to normal PF resin by more than 50%. The synthetic adhesive show with excellent water resistance and environmental friendliness, which had a 28h boil-dry-boil wet bonding strength of 1,73MPa according to standard JIS K6806-2003 and a formaldehyde emission of 0,045mg/L according to standard JIS A1460-2003. The structural properties and their thermal properties of cured adhesives were evaluated using Fourier transform infrared (FT-IR) and differential scanning calorimetry (DSC). The FT-IR analysis confirmed the expected chemical structure as the Chinese fir liquid reacted with formaldehyde and phenol which occurred at the wavenumbers of 1733, 1698, 1652cm-1 and 1077, 1048 cm-1. Although the DSC results indicated that the Chinese fir-based adhesive's curing need higher temperature than the control PF resin, the higher curing temperature hardly cripple the availability of Chinese fir-based resin in the plywood production.

The microstructure and microwave absorption of carbon-coated Cu nanocapsules have been investigated. Carbon-coated Cu nanocapsules have been synthesized by an arc-discharge method. The paraffin-Cu/C nanocapsules composite shows excellent electromagnetic (EM) absorption properties. An optimal reflection loss (RL) value of - 40.0 dB is reached at 10.52 GHz for a layer 1.9 mm thickness. RL exceeding - 20 dB can be realized in any interval within the 1-18 GHz range by choosing an appropriate thickness of the absorbent layer between 1.1 and 10.0 mm. Theoretical simulation for the microwave absorption using the transmission line theory agrees reasonably well with the experimental results. The EM-wave absorption properties of nanocapsules materials are illustrated by means of an absorption-tube-map. The carbon-coated Cu nanocapsule is an attractive candidate for EM-wave absorption, which significantly enriches the family of EM-wave nanoabsorbents.

A facile hydrothermal strategy is proposed to synthesize flower-like β-Co(OH)2 hierarchical microspherical superstructures with a diameter of 0.5-1.5 μm, which are self-assembled by β-Co(OH)2 nanosheets with the average thickness ranging between 20 and 40 nm. The magnetocaloric effect associated with magnetic phase transitions in Co(OH)2 superstructures has been investigated. A sign change in the magnetocaloric effect is induced by a magnetic field, which is related to a filed-induced transition from the antiferromagnetic to the ferromagnetic state below the Néel temperature. The large reversible magnetic-entropy change -ΔSm (13.4 J/kg K at 15 K for a field change of 5 T) indicates that flower-like Co(OH)2 superstructures is a potential candidate for application in magnetic refrigeration in the low-temperature range.

Foi desenvolvido um método simples, sensível e rápido de extração em fase sólida utilizando cromatografia liquida de alta eficiência (SPE-CLAE) para a determinação simultânea de quatro cumarinas, psoralen, isopsoralen, imperatorina e isoimperatorina, utilizando ostole como padrão interno. Utilizando este método, foi analisada a farmacocinética destas cumarinas em plasma de ratos após administração oral de uma cápsula "YIGONG" da medicina chinesa tradicional. Amostras de plasma foram pré-tratadas com extração em fase sólida utilizando cartuchos Extract-CleanTM e a separação dos extratos foi realizada com uma coluna Eurospher C18 utilizando metanol-água como fase móvel. Os limites de quantificação foram 9,7 ng mL-1 para psoralen, 7,1 ng mL-1 para isopsoralen, 6,7 ng mL-1 para imperatorina e 3,0 ng mL-1 para isoimperatorina. As recuperações médias das quatro cumarinas contidas no plasma de ratos foram bem acima de 80%. As precisões determinadas para 6 dias estiveram sempre dentro de 10%. Concluiu-se que o método estabelecido é adequado para estudos farmacocinéticos destas quatro cumarinas em plasma de ratos.

A simple, sensitive and rapid solid-phase extraction method by using high performance liquid chromatography (SPE-HPLC) was developed for simultaneous determination of four coumarins, psoralen, isopsoralen, imperatorin and isoimperatorin using osthole as internal standard. Using this method, pharmacokinetic of these coumarins in rat plasma was analyzed after oral administration of a traditional Chinese medicine "YIGONG" capsule. Plasma samples were pretreated with solid-phase extraction using Extract-CleanTM cartridges, and separation of the extracts was performed on a Eurospher C18 column using methanol-water as mobile phase. The quantification limits for psoralen, isopsoralen, imperatorin and isoimperatorin in rat plasma were 9.7, 7.1, 6.7 and 3.0 ng mL-1, respectively. Average extract recoveries of the four coumarins from rat plasma were all over 80%. Precisions determined from 6 days were all within 10%. It was concluded that the established method is suitable for pharmacokinetic studies of these four coumarins in rat plasma.