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Under pressure from social criticism and an unclear future, tobacco researchers have begun to seek alternative uses for the product. Here, we present our study on isolating tobacco compounds with fungicidal activity, which could be used as plant-derived pesticides. Using Valsa mali as the target fungus, agar plate tests were conducted to evaluate the fungicidal activity of various tobacco extracts, including tobacco leaves extracts prepared with different solvents, extracts of different tobacco cultivars, and samples from different tobacco organs. Fungal growth morphology was used as the criterion to evaluate the fungicidal activity of tobacco extracts. Correlation analyses between the fungicidal activities and the chemical components of tobacco extracts indicated the major chemical constituents with fungicidal activity. Then, the active compounds were isolated and their effects on the ultra-microstructures of V. mali was analyzed using scanning- and transmission-electron microscopy. The results suggested that tobacco extracts prepared with solvents of weaker polarity had higher fungicidal activity, and the inhibitory activity of tobacco extracts against V. mali was also cultivar dependent. Furthermore, the fungicidal effects of tobacco flower extracts were higher than those of the leaf extracts. Chemical analysis indicated that cembranoids were the main fungicidal substances, which act by destroying the endometrial structure of the fungus. Tobacco cembranoids at 80 μg/mL could completely inhibit the growth of V. mali, with an EC50 value of 13.18 μg/mL. Our study therefore suggests that tobacco leaves and inflorescences are excellent plant resources for the biological control of V. mali. [ABSTRACT FROM AUTHOR]

A d15 mode piezoelectric energy harvester (PEH) with two PZT-51 elements in series connection (SC), in which the elements are arranged along the width direction, was fabricated, and it is compared with the traditional d15 mode PEH with a single PZT-51 element (SPEH) to discuss the output peak-to-peak voltage (Up-p). The energy harvesting performances of PEHSC are modeled by combining the single degree of freedom model and the electrical model with the piezoelectric constitutive equation of the d15 mode. The energy harvesting performances of PEHSC were systematically measured at various frequencies and load resistances, and Up-p and output power are 12.4 V and 8:7 W at a load resistance of 2:2 M and resonance frequency of 73 Hz. The experimental Up-p of PEHSC and SPEH are 25.4 and 15.6 V at the resonance frequencies under open circuit condition, and this indicates that the SC structure can improve the energy harvesting performance for d15 mode PEH. The experimental Up-p, output power and the transient voltage-time curve of PEHSC are in agreement with the results of finite element numerical solutions and theoretical modeling, so they are acceptable. The d15 mode and SC structure could potentially improve the energy harvesting performance of PEHs. [ABSTRACT FROM AUTHOR]

Samples of lead zirconate titanate Pb(Zr0.53Ti0.47)O3 with europium (Eu) doping concentration of 0, 0.5, 1.5, 3 mol% (PEZT) were fabricated by sol–gel method. XRD spectra showed that the introduction of Eu into PZT favored the growth of (100) orientation. With 3% Eu content, the preferential orientation of the film converted from (111) to (100) orientation. The Eu-doped PZT films exhibited lower leakage current less than 10-9 A/cm2 and the behavior of leakage current was discussed in terms of defect chemistry theorem. When Eu content was 1.5%, the remanent polarization (Pr) increased to 28 μ C/cm2 which was much higher than that of undoped PZT film. [ABSTRACT FROM AUTHOR]

Calibration of the micro force sensors is necessary for the measurement of microNewton forces, which are critical to analytical applications of micro force sensor in the analysis of micromanipulators, microrobots and microgrippers. This paper proposes a novel calibration system to calibrate PZT thin film micro force sensor using the bimorph probe as the loading part. Sensitivities of PZT thin film micro force sensors were calibrated by the calibration system composed of the drive system and the testing system. The drive system combines 3-dimensional positioning stage, a bimorph probe and a frequency synthesizer, and the testing system combines an electronic balance for static state or a charge amplifier and a lock-in amplifier for the quasi static state. [ABSTRACT FROM AUTHOR]

A blind source separation based vibration control method using piezoelectric self-sensing actuator is proposed. Two piezoelectric ceramic patches acting as actuators and two current amplifiers consist of the self-sensing bridge circuit. Each piezoelectric current is a mixture of strain rate current and capacitor current. As they are orthogonal and independent with each other, the blind source separation technique is introduced to obtain the pure strain rate signal. An effort is made to solve the problem of BSS uncertainty in separation order. Open loop experimental results on cantilever beam show the feasibility and validity of the proposed method. [ABSTRACT FROM AUTHOR]

PZT thin film devices are very competitive when charge signal and force outputs are demanded. A Pb(Zr0.5Ti0.5)O3thin film with 24 coating layers is deposited by a sol-gel method. An array of three piezoelectric microcantilevers is fabricated using the wet and dry combined bulk micromachining techniques. Each microcantilever has a two-segment top electrode in different dimensions. The actuating and sensing capability of the six segments on the three microcantilevers are measured. It is proved that the proposed piezoelectric microcantilevers have both actuating and sensing functions; different proportion partition results in the diversity of the actuating and sensing capability. At the same location, the longer the piezoelectric segment is, the stronger actuating and sensing capability it has. The maximum actuating sensitivity and sensing sensitivity before poling treatment are 16.7 µN V?1and 13.44 pC µm?1, respectively, which become about twice as big after poling. We may choose the appropriate microcantilevers to satisfy our purpose on some specific condition where force feedback and object manipulation are needed simultaneously. A hysteresis phenomenon is encountered in the actuating process while not in the sensing process. [ABSTRACT FROM AUTHOR]

Background and Objectives: To explore the effect of nutrition management under ERAS concept in patients with spinal tuberculosis. Methods and Study Design: The study was conducted in an orthopedic ward of a tertiary grade A special hospital in Beijing. The patients admitted from January 1, 2021 to June 27, 2023 were screened for inclusion. The qualified patients were randomized into experimental group or control group. The experimental group received perioperative nutrition management under the concept of ERAS while the control group received routine perioperative management in hospital. The data was collected on the next day of admission, the next day and the sixth day after operation, including laboratory indicators (lymphocyte count, hemoglobin level, etc), intraoperative bleeding volume, postoperative exhaust, defecation time, drainage volume, albumin infusion amount, nutritional risk score, length of stay, hospitalization costs, etc. Univariate analysis and multivariate analysis correcting for gender, age, and baseline values were performed using SPSS24.0. Results: A total of 127 patients with spinal tuberculosis completed the study. Compared with the control group, the intraoperative blood loss (p=0.028) in the experimental group was significantly reduced, the postoperative exhaust time (p=0.012) and defecation time (p=0.012) were significantly shortened, and the nutritional status (p<0.001) was significantly improved. Besides, the results of multivariate analysis are robust after correcting potential confounding factors. Conclusions: Nutrition management under the concept of ERAS is helpful to reduce intraoperative bleeding, promote postoperative flatus and defecation, and improve nutritional status in patients with spinal tuberculosis, which may further improve their clinical outcome and prognosis. [ABSTRACT FROM AUTHOR]

Recombinant therapeutic proteins are becoming very important pharmaceutical agents for treating intractable diseases. Most biopharmaceutical proteins are produced in mammalian cells because this ensures correct folding and glycosylation for protein stability and function. However, protein production in mammalian cells has several drawbacks, including heterogeneity of glycans attached to the produced protein. In this study, we established cell lines with high-mannose-type N-linked, lowcomplexity glycans. We first knocked out two genes encoding Golgi mannosidases (MAN1A1 and MAN1A2) in HEK293 cells. Single knockout (KO) cells did not exhibit changes in N-glycan structures, whereas double KO cells displayed increased highmannose- type and decreased complex-type glycans. In our effort to eliminate the remaining complex-type glycans, we found that knocking out a gene encoding the endoplasmic reticulum mannosidase I (MAN1B1) in the double KO cells reduced most of the complex-type glycans. In triple KO (MAN1A1, MAN1A2, and MAN1B1) cells, Man9GlcNAc2 and Man8GlcNAc2 were the major N-glycan structures. Therefore, we expressed two lysosomal enzymes, -galactosidase-A and lysosomal acid lipase, in the triple KO cells and found that the glycans on these enzymes were sensitive to endoglycosidase H treatment. The N-glycan structures on recombinant proteins expressed in triple KO cells were simplified and changed from complex types to high-mannose types at the protein level. Our results indicate that the triple KO HEK293 cells are suitable for producing recombinant proteins, including lysosomal enzymes with high-mannose-type N-glycans. [ABSTRACT FROM AUTHOR]

Ag recognition and Ab production in B cells are major components of the humoral immune response. In the current study, we found that the core fucosylation catalyzed by a1,6-fucosyltransferase (Fut8) was required for the Ag recognition of BCR and the subsequent signal transduction. Moreover, compared with the 3-83 B cells, the coalescing of lipid rafts and Ag-BCR endocytosis were substantially reduced in Fut8 -knockdown (3-83-KD) cells with p31 stimulation and then completely restored by reintroduction of the Fut8 gene to the 3-83-KD cells. Indeed, Fut8-null (Fut8-/-) mice evoked a low immune response following OVA immunization. Also, the frequency of IgG-producing cells was significantly reduced in the Fut8-/- spleen following OVA immunization. Our results clearly suggest an unexpected mode of BCR function, in which the core fucosylation of IgG-BCR mediates Ag recognition and, concomitantly, cell signal transduction via BCR and Ab production. [ABSTRACT FROM AUTHOR]