Design and Testing of an Online Fertilizing Amount Detection Device Based on the Moment Balance Principle

Based on the principle of moment balance, this paper designs a fertilizer application amount online detection device, which is mainly composed of two major parts: the fertilizer guide mechanism and the fertilizer metering and discharging mechanism.Under the electromagnetic reversing and buffering of the fertilizer guide mechanism, the fertilizer discharged into the device falls alternately into the storage box of the two metering units of the metering and discharging mechanism. Once the gravity of the fertilizer in the storage box is greater than the suction of the electromagnetic sucker, the fertilizer discharging board is automatically opened for fertilizer discharge, and the metering pulse signal is accumulated once. Meanwhile, the fertilizer guide plate is driven by the electromagnetic commutator to reverse the material, and then another storage box is started for fertilizer storage and metering. In this approach, online detection of fertilizer flow can be realized by repeatedly guiding and reversing and metering the incoming fertilizer. According to the single metering fertilizer quality and the number of metering pulse signals, the fertilization amount can be calculated in real-time.The performance of the device was verified by bench test. The test results indicated that: The established fertilizer application detection model is a quadratic function (R2>0.98), and the verification error was less than 3.73% in the detection of alternating cycle fertilizer discharge; the coefficient of determination (R2) and the root mean square error (RMSE) reached 0.992 and 9.858 respectively, indicating high detection accuracy of the device is

Exosomes and Their Therapeutic Potentials of Stem Cells

Exosomes, a group of vesicles originating from the multivesicular bodies (MVBs), are released into the extracellular space when MVBs fuse with the plasma membrane. Numerous studies indicate that exosomes play important roles in cell-to-cell communication, and exosomes from specific cell types and conditions display multiple functions such as exerting positive effects on regeneration in many tissues. It is widely accepted that the therapeutic potential of stem cells may be mediated largely by the paracrine factors, so harnessing the paracrine effects of stem and progenitor cells without affecting these living, replicating, and potentially pluripotent cell populations is an advantage in terms of safety and complexity. Ascending evidence indicated that exosomes might be the main components of paracrine factors; thus, understanding the role of exosomes in each subtype of stem cells is far-reaching. In this review, we discuss the functions of exosomes from different types of stem cells and emphasize the therapeutic potentials of exosomes, providing an alternative way of developing strategies to cure diseases

COVID-19 in Japan: What could happen in the future? (Recent developments on inverse problems for partial differential equations and their applications)

This paper was finished in February, 2020 and posted in MedRxiv on Feb. 28th, 2020.COVID-19 has been impacting on the whole world critically and constantly Since December 2019. We have independently developed a novel statistical time delay dynamic model on the basis of the distribution models from CCDC. Based only on the numbers of confirmed cases in different regions in China, the model can clearly reveal that the containment of the epidemic highly depends on early and effective isolation. We apply the model on the epidemic in Japan and conclude that there could be a rapid outbreak in Japan if no effective quarantine measures are carried out immediately

TLE3 represses colorectal cancer proliferation by inhibiting MAPK and AKT signaling pathways

Primer Sequences used for RT-qPCR (5’ to 3’). (DOCX 13 kb

Robust estimation of bacterial cell count from optical density

Optical density (OD) is widely used to estimate the density of cells in liquid culture, but cannot be compared between instruments without a standardized calibration protocol and is challenging to relate to actual cell count. We address this with an interlaboratory study comparing three simple, low-cost, and highly accessible OD calibration protocols across 244 laboratories, applied to eight strains of constitutive GFP-expressing E. coli. Based on our results, we recommend calibrating OD to estimated cell count using serial dilution of silica microspheres, which produces highly precise calibration (95.5% of residuals <1.2-fold), is easily assessed for quality control, also assesses instrument effective linear range, and can be combined with fluorescence calibration to obtain units of Molecules of Equivalent Fluorescein (MEFL) per cell, allowing direct comparison and data fusion with flow cytometry measurements: in our study, fluorescence per cell measurements showed only a 1.07-fold mean difference between plate reader and flow cytometry data

Harmonic Injection-Based Power Fluctuation Control of Three-Phase PV Systems under Unbalanced Grid Voltage Conditions

Unbalanced voltage will inevitably cause power and DC voltage fluctuations in a three-phase PV system. The deterioration of power quality will do great harm to the PV panels and the loads, so it is necessary to suppress the power fluctuations. This paper further explores the coefficients control strategy of PV converters under unbalanced voltage conditions, aiming to suppress power fluctuations by controlling the injection of some specific orders of current harmonics into the grid. In order to achieve this, the current reference of the PV inverter has been changed by bringing in two control coefficients, and the expression of each order of the current harmonics has been deduced. Based on the standards of PV systems, the regions from which the coefficients can be selected are determined. Then, by tuning these coefficients in the feasible regions, the output parameters (power fluctuation, current THD and odd harmonics) can be controlled precisely. The model of this method is built and simulated in PSCAD/EMTDC, and as a result, it is shown that the power fluctuations can be restricted according to different power quality requirements

Meta-Analysis for Clinical Evaluation of Xingnaojing Injection for the Treatment of Cerebral Infarction

Objective: Xingnaojing injection (XNJ) is derived from An-Gong-Niu-Huang pill, a well-known traditional Chinese patent medicine, which is widely used for stroke. To evaluate the therapeutic effect of XNJ on cerebral infarction, an extensive meta-analysis was used.Methods: Six major electronic databases including the Chinese Biomedical Database (CBM), Wanfang, the VIP medicine information system (VMIS) and the China National Knowledge Infrastructure (CNKI), PubMed, Embase, and the Cochrane Library were examined to retrieve randomized controlled trials designed to evaluate the clinical efficacy of XNJ in treating CI before November 26, 2016.Results: There were 53 randomized controlled trials with 4915 participants in this study. The results reflected that compared with the conventional therapy (CT) alone, XNJ could significantly improve the overall response rate (OR = 3.56, 95% CI [2.94, 4.32], P < 0.00001), and clinical symptom (including increasing activities of daily living (ADL, MD = 10.23, 95% CI [9.47, 10.99], P < 0.00001), and reduce infarction size (MD = -1.83, 95% CI [-2.49, -1.16], P < 0.00001)). However, there was no significant difference between the XNJ treatment and conventional therapy in Glasgow Coma Scale (GCS, P = 0.32). Neurological deficit score demonstrated that XNJ could significantly reduce the score in two different evaluation criterions as National Institutes of Health Stroke Scale (NIHSS, MD = -3.44, 95% CI [-4.52, -2.36], P < 0.00001), and the Chinese Stroke Scale (CSS, MD = -5.72, 95% CI [-6.94, -4.50], P < 0.00001). Additionally, serum MMPs, including MMP-2 and MMP-9 were significantly reduced by XNJ treatment compared with conventional therapy (MD = -11.24, 95% CI [-20.83, -1.65], P = 0.02; MD = -25.08, 95% CI [-35.49, -14.67], P < 0.00001, respectively). Moreover, XNJ was able to improve hemorrheology in reducing whole blood viscosity, plasma viscosity, and hematocrit (MD = -1.44, 95% CI [-2.18, 0.70], P = 0.001; MD = -0.22, 95% CI [-0.37, -0.07], P = 0.003; MD = -3.63, 95% CI [-6.23, -1.03], P = 0.006, respectively). The therapeutic efficacy of XNJ was found associated with improving hemodynamics (increasing peak-flow rate, and average velocity) (MD = 12.66, 95% CI [10.50, 14.81], P < 0.00001; MD = 9.90, 95% CI [8.63, 11.17], P < 0.00001). XNJ was also related to reducing cholesterol and triglyceride (MD = -1.06, 95% CI [-1.21, -0.92], P < 0.00001; MD = -1.05, 95% CI [-1.12, -0.97], P < 0.00001).Conclusion: Despite the sample size and the poor quality of the included studies of this review, the results of the research showed that XNJ might be a beneficial therapeutic method for the treatment of cerebral infarction