由苯甲醇合成苯甲酸乙酯综合制备实验的课程思政设计

将苯甲酸合成与苯甲酸乙酯制备两个经典实验改造为综合实验,并以改进合成过程实现绿色、高效转化为案例,引导学生通过查阅文献,综合分析合成过程,指出原合成方法存在的问题和不足,提出改进的建议,在此过程中,引导学生将法律法规、实验规范、学科伦理、绿色理念、环保和可持续发展理念等融入实验的设计和实施全过程,使学生在受到基本操作训练的同时得到素质的全面提升。

Real-time model correction using Kalman filter for Raman-controlled cell culture processes

Raman spectroscopy has found extensive use in monitoring and controlling cell culture processes.In this context,the prediction accuracy of Raman-based models is of paramount importance.However,models established with data from manually fed-batch cultures often exhibit poor performance in Raman-controlled cultures.Thus,there is a need for effective methods to rectify these models.The objective of this paper is to investigate the efficacy of Kalman filter(KF)algorithm in correcting Raman-based models during cell culture.Initially,partial least squares(PLS)models for different components were constructed using data from manually fed-batch cultures,and the predictive performance of these models was compared.Subsequently,various correction methods including the PLS-KF-KF method proposed in this study were employed to refine the PLS models.Finally,a case study involving the auto-control of glucose concentration demonstrated the application of optimal model correction method.The results indicated that the original PLS models exhibited differential performance between manually fed-batch cultures and Raman-controlled cultures.For glucose,the root mean square error of prediction(RMSEP)of manually fed-batch culture and Raman-controlled culture was 0.23 and 0.40 g·L^(-1).With the implementation of model correction methods,there was a significant improvement in model performance within Raman-controlled cultures.The RMSEP for glucose from updating-PLS,KF-PLS,and PLS-KF-KF was 0.38,0.36 and 0.17 g·L^(-1),respectively.Notably,the proposed PLS-KF-KF model correction method was found to be more effective and stable,playing a vital role in the automated nutrient feeding of cell cultures.

RuO_(2)-PdO nanowire networks with rich interfaces and defects supported on carbon toward the efficient alkaline hydrogen oxidation reaction

Interfacial engineering is a promising approach for enhancing electrochemical performance,but rich and efficient interfacial active sites remain a challenge in fabrication.Herein,RuO_(2)-PdO heterostructure nanowire networks(NWs) with rich interfaces and defects supported on carbon(RuO_(2)-PdO NWs/C) for alkaline hydrogen oxidation reaction(HOR) was formed by a seed induction-oriented attachment-thermal treatment method for the first time.As expected,the RuO_(2)-PdO NWs/C(72.8% Ru atomic content in metal) exhibits an excellent activity in alkaline HOR with a mass specific exchange current density(jo,m) of 1061 A gRuPd-1,which is 3.1 times of commercial Pt/C and better than most of the reported nonPt noble metal HOR electrocatalysts.Even at the high potential(~0.5 V vs.RHE) or the presence of CO(5 vol%),the RuO_(2)-PdO NWs/C still effectively catalyzes the alkaline HOR.Structure/electrochemical analysis and theoretical calculations reveal that the interfaces between RuO_(2) and PdO act as the active sites.The electronic interactions between the two species and the rich defects for the interfacial active sites weaken the adsorption of Had,also strengthen the adsorption of OHad,and accelerate the alkaline HOR process.Moreover,OHadon RuO_(2) can spillover to the interfaces,keeping the RuO_(2)-PdO NWs/C with the stable current density at higher potential and high resistance to CO poisoning.

The dynamic arms race during the early invasion of woodland strawberry by Botrytis cinerea revealed by dual dense high-resolution RNA-seq analyses

Necrotrophic pathogens replicate massively upon colonizing plants,causing large-scale wilting and death of plant tissues.Under-standing both mechanisms of pathogen invasion and host response processes prior to symptom appearance and their key regulatory networks is therefore important for defense against pathogen attack.Here,we investigated the mechanisms of interaction between woodland strawberry(Fragaria vesca)leaves and gray mold pathogen(Botrytis cinerea)at 14 infection time points during the first 12 hours of the infection period using a dense,high-resolution time series dual transcriptomic analysis,characterizing the arms race between strawberry F.vesca and B.cinerea before the appearance of localized lesions.Strawberry leaves rapidly initiated strong systemic defenses at the first sign of external stimulation and showed lower levels of transcriptomic change later in the infection process.Unlike the host plants,B.cinerea showed larger-scale transcriptomic changes that persisted throughout the infection process.Weighted gene co-expression network analysis identified highly correlated genes in 32 gene expression modules between B.cinerea and strawberry.Yeast two-hybrid and bimolecular fluorescence complementation assays revealed that the disease response protein FvRLP2 from woodland strawberry interacted with the cell death inducing proteins BcXYG1 and BcPG3 from B.cinerea.Overexpression of FvRLP2 in both strawberry and Arabidopsis inhibited B.cinerea infection,confirming these genes’respective functions.These findings shed light on the arms race process by which B.cinerea invades host plants and strawberry to defend against pathogen infection.

Reviews on Current Carbon Emission Reduction Technologies and Projects and their Feasibilities on Ships

Concern about global climate change is growing, and many projects and researchers are committed to reducing greenhouse gases from all possible sources. International Maritime Organization (IMO) has set a target of 20% CO2 reduction from shipping by 2020 and also presented a series of carbon emission reduction methods, which are known as Energy Efficiency Design Index (EEDI) and Energy Efficiency Operation Indicator (EEOI). Reviews on carbon emission reduction from all industries indicate that, Carbon Capture and Storage (CCS) is an excellent solution to global warming. In this paper, a comprehensive literature review of EEDI and EEOI and CCS is conducted and involves reviewing current policies, introducing common technologies, and considering their feasibilities for marine activities, mainly shipping. Current projects are also presented in this paper, thereby illustrating that carbon emission reduction has been the subject of attention from all over the world. Two case ship studies indicate the economic feasibility of carbon emission reduction and provide a guide for CCS system application and practical installation on ships.

A method to model the effect of pre-existing cracks on P-wave velocity in rocks

Crack closure is one of the reasons inducing changes of P-wave velocity of rocks under compression.In this context,a method is proposed to investigate the relationships among P-wave velocity,pre-existing cracks,and confining pressure based on the discrete element method(DEM).Pre-existing open cracks inside the rocks are generated by the initial gap of the flat-joint model.The validity of the method is evaluated by comparing the P-wave velocity tested on a sandstone specimen with numerical result.As the crack size is determined by the diameter of particles,the effects of three factors,i.e.number,aspect ratio,and orientation of cracks on the P-wave velocity are discussed.The results show that P-wave velocity is controlled by the(i.e.number) of open micro-cracks,while the closure pressure is determined by the aspect ratio of crack.The reason accounting for the anisotropy of P-wave velocity is the difference in crack number in measurement paths.Both of the number and aspect ratio of cracks can affect the responses of P-wave velocity to the applied confining pressure.Under confining pressure,the number of open cracks inside rocks will dominate the lowest P-wave velocity,and the P-wave velocity of the rock containing narrower cracks is more sensitive to the confining pressure.In this sense,crack density is difficult to be back-calculated merely by P-wave velocity.The proposed method offers a means to analyze the effect of pre-existing cracks on P-wave velocity.

Applications of Fractional Lower Order Time-frequency Representation to Machine Bearing Fault Diagnosis

The machinery fault signal is a typical non-Gaussian and non-stationary process. The fault signal can be described by SaS distribution model because of the presence of impulses.Time-frequency distribution is a useful tool to extract helpful information of the machinery fault signal. Various fractional lower order(FLO) time-frequency distribution methods have been proposed based on fractional lower order statistics, which include fractional lower order short time Fourier transform(FLO-STFT), fractional lower order Wigner-Ville distributions(FLO-WVDs), fractional lower order Cohen class time-frequency distributions(FLO-CDs), fractional lower order adaptive kernel time-frequency distributions(FLO-AKDs) and adaptive fractional lower order time-frequency auto-regressive moving average(FLO-TFARMA) model time-frequency representation method.The methods and the exiting methods based on second order statistics in SaS distribution environments are compared, simulation results show that the new methods have better performances than the existing methods. The advantages and disadvantages of the improved time-frequency methods have been summarized.Last, the new methods are applied to analyze the outer race fault signals, the results illustrate their good performances.

Ultrasonic Scattered Field Distribution of One and Two Cylindrical Solids with Phased Array Technique

The scattered fields of plane waves in a solid from a cylinder or sphere are critical in determining its acoustic characteristics as well as in engineering applications. This paper investigates the scattered field distributions of different incident waves created by elastic cylinders embedded in an elastic isotropic medium. Scattered waves, including longitudinal and transverse waves both inside and outside the cylinder, are described with specific modalities under an incident plane wave. A model with a scatterer embedded in a structural steel matrix and filled with aluminum is developed for comparison with the theoretical solution. The frequency of the plane wave ranged from 235 kHz to 2348 kHz, which corresponds to scaling factors from 0.5 to 5. Scattered field distributions in matrix materials blocked by an elastic cylindrical solid have been obtained by simulation or calculated using existing parameters. The simulation results are in good agreement with the theoretical solution, which supports the correctness of the simulation analysis. Furthermore, ultrasonic phased arrays are used to study scattered fields by changing the characteristics of the incident wave. On this foundation, a partial preliminary study of the scattered field distribution of double cylinders in a solid has been carried out, and the scattered field distribution at a given distance has been found to exhibit particular behaviors at different moments. Further studies on directivities and scattered fields are expected to improve the quantification of scattered images in isotropic solid materials by the phased array technique.

Genomic and transcriptomic alterations following intergeneric hybridization and polyploidization in the Chrysanthemum nankingense×Tanacetum vulgare hybrid and allopolyploid (Asteraceae)

Allopolyploid formation involves two major events:interspecific hybridization and polyploidization.A number of species in the Asteraceae family are polyploids because of frequent hybridization.The effects of hybridization on genomics and transcriptomics in Chrysanthemum nankingense×Tanacetum vulgare hybrids have been reported.In this study,we obtained allopolyploids by applying a colchicine treatment to a synthesized C.nankingense×T.vulgare hybrid.Sequence-related amplified polymorphism(SRAP),methylation-sensitive amplification polymorphism(MSAP),and high-throughput RNA sequencing(RNA-Seq)technologies were used to investigate the genomic,epigenetic,and transcriptomic alterations in both the hybrid and allopolyploids.The genomic alterations in the hybrid and allopolyploids mainly involved the loss of parental fragments and the gain of novel fragments.The DNA methylation level of the hybrid was reduced by hybridization but was restored somewhat after polyploidization.There were more significant differences in gene expression between the hybrid/allopolyploid and the paternal parent than between the hybrid/allopolyploid and the maternal parent.Most differentially expressed genes(DEGs)showed down-regulation in the hybrid/allopolyploid relative to the parents.Among the non-additive genes,transgressive patterns appeared to be dominant,especially repression patterns.Maternal expression dominance was observed specifically for down-regulated genes.Many methylase and methyltransferase genes showed differential expression between the hybrid and parents and between the allopolyploid and parents.Our data indicate that hybridization may be a major factor affecting genomic and transcriptomic changes in newly formed allopolyploids.The formation of allopolyploids may not simply be the sum of hybridization and polyploidization changes but also may be influenced by the interaction between these processes.

Acoustic radiation force on a multilayered sphere in a Gaussian standing field

We develop a model for calculating the radiation force on spherically symmetric multilayered particles based on the acoustic scattering approach.An expression is derived for the radiation force on a multilayered sphere centered on the axis of a Gaussian standing wave propagating in an ideal fluid,The effects of the sound absorption of the materials and sound wave on acoustic radiation force of a multilayered sphere immersed in water are analyzed,with particular emphasis on the shell thickness of every layer,and the width of the Gaussian beam.The results reveal that the existence of particle trapping behavior depends on the choice of the non-dimensional frequency ka,as well as the shell thickness of each layer.This study provides a theoretical basis for the development of acoustical tweezers in a Gaussian standing wave,which may benefit the improvement and development of acoustic control technology,such as trapping,sorting,and assembling a cell,and drug delivery applications.

Chemometric identification of canonical metabolites linking critical process parameters to monoclonal antibody production during bioprocess development

A deeper understanding of the biological events occurring when bioprocess parameters changed will be of great value in improving the monoclonal antibodies (mAbs) production. Design of experiment (DoE) was applied to investigate the effect of process parameters (pH, temperature shift and dissolve oxygen (DO)) on protein titer. The key metabolites connecting the critical process parameters (CPPs) with monoclonal antibody production were identified by different chemometrics tools. Finally, the biological events of marker metabolites relating with titer improvement were concluded. pH and temperature shift were identified as CPPs that affect the target protein titer. A series of metabolites influenced by the altered CPPs and correlated with protein titer were screened by principal component analysis (PCA) and Pearson' correlation test. The marker metabolites and their pathways linking CPPs to target protein titer in different culture phases were summarized. Metabolomics and chemometrics are promising data-driven tools to shine light into the biological black box between the bioprocess parameters and process performance.

Small-scale alpine topography at low latitudes and high altitudes:refuge areas of the genus Chrysanthemum and its allies

Cultivated chrysanthemum(Chrysanthemum morifolium Ramat.)is an economically important ornamental plant species grown worldwide.However,the origin of the genus Chrysanthemum remains unclear.This study was conducted in the Hengduan Mountains,Yunnan Province.We took advantage of a special geographic region where the southernmost species of Ajania and the highest altitude population of Chrysanthemum indicum coexist to investigate their evolutionary origins.Diversity analysis of 9 populations of 5 species that came from 3 genera was carried out based on morphological traits and SRAP markers.Furthermore,topographical and ecological analyses and surveys of the vegetation communities in the plots were carried out for correlation analysis,and past data were used to reconstruct the ancient topography and vegetation to estimate the migration path and divergence time.We found that Chrysanthemum and Ajania were closely related based on the smooth transition states among marginal female florets and their common pollination system.The genetic relationship between Phaeostigma and Chrysanthemum was relatively distant,and Ajania was between them.Low light intensity and relatively humid habitats may be driving the elongation and evolution of marginal female florets.We found that Chrysanthemum and related genera were largely restricted to stony topographies at an altitude of~3000 m.a.s.l.and in specialized alpine coniferous(Pinus)and broadleaved(Quercus)mixed forest marginal communities.These stony topographies have become ecological islands of refuge for these species in the current interglacial period.The Hengduan Mountains play a key role in the evolution,divergence,and survival of Chrysanthemum and its allies.

A Rare Case of Multiple Scar Contractures after Burn Injury

A nine-year-old girl sustained extreme postburn contractures of the face, neck, both axillae, elbows, wrists, and ankles, due to flame injury 5 years ago. No primary and plastic surgical burn treatment was available in a remote area of China. From October, 2005 to April, 2007, all adhesions were released in five operations and the huge defects covered with local musculo-cutaneous flaps, z-plasties, and with thick split skin gafts. This led to an optimal functional result and an aesthetic restoration of the face, giving her, back her self-esteem in daily life.

Exploration and Discussion on the Clinical Therapeutic Effects of the Application of Cross-Injury Vertebral Fixation and Via-Injury Vertebrae Fixation in the Treatment of Bone Tumor with Thoracolumbar Spine Fracture

Objective:To explore and discuss the clinical therapeutic effects of the application of cross-injury vertebral fixation and via-injury vertebrae fixation in the treatment of bone tumor with thoracolumbar spine fracture.Methods:A total of 58 patients with bone tumors and thoracolumbar spine fractures admitted to our hospital from February to February 2019 were selected as the study subjects.They were randomly divided into control group and observation group,with 29 cases in each group.The patients in the control group received cross-injury vertebral fixation treatment,while the patients in the observation group were treated with via-injury vertebral fixation.The therapeutic effects of the two groups were compared.Results:The operation time and hospitalization time of the observation group were significantly shorter than those of the control group(P<0.05),and the postoperative drainage volume of the intraoperative blood loss was significantly less than that of the control group(P<0.05).There was no significant difference in postoperative pain and spinal JOA scores between the two groups(P>0.05);there was no significant difference in the compression ratio of the injured vertebrae and the kyphosis Cobb angle between the two groups(P>0.05),after the operation,the two groups of patients were significantly reduced,and the compression ratio of the injured vertebrae and kyphosis Cobb angle of the observation group were more obvious(P<0.05);the vertebral height loss and Cobb angle loss in the observation group were significantly lower than those in the control group(P<0.05).Conclusion:In the treatment of bone tumor with thoracolumbar spine fracture,compared with cross-injury vertebral fixation,via-injury vertebral fixation has a more significant clinical effect and is more suitable for clinical application and promotion.

Study on Cisplatin Aggravating DNA Damage and Causing a High Apoptosis Rate on Breast Cancer MCF-7 Cells

[Objectives] To investigate the mechanism of DNA damage of cisplatin( DDP),a broad spectrum anticancer drug on breast cancer MCF-7 cells,and to study the mechanism of apoptosis induced by DDP.[Methods]MCF-7 cells were treated by DDP( 0 mg/L,2 mg/L,4 mg/L,6 mg/L,6 mg/L,and 10 mg/L) for 48 hours. MTT assay was used to detect the inhibitory effect of DDP on MCF-7 cells and IC50 value was calculated. Western blot was adopted to detect the expression of γ-H2 AX,which was the marker of DNA double stranded breaks( DSBs) and ATM( sensory molecules of DSBs),the apoptotic signal transduction molecule cleaved caspase-3,and the proteins associated with apoptosis calpain.[Results]DDP inhibited MCF-7 cell activity in a concentration-dependent manner and IC50 was 7. 57 mg/L. In contrast to the control group( without DDP treatment),MCF-7 cells with DDP treatment expressed more γ-H2 AX,ATM,cleaved caspase-3 and calpain.[Conclusions] DDP could inhibit the activity of breast cancer MCF-7 cells. Its mechanisms may be associated with inhibition of MCF-7 cell apoptosis,induction of DNA double strand breaking and the expression of pro-apoptotic protein up-regulation.

Effect Observation of Clinical Treatment with Oxaliplatin and Tiggio for Biliary Tract Tumors on Advanced Stage

Objective:To investigate the effect of oxaliplatin combined with tiggio in the treatment of advanced biliary tract tumors.Methods:The research period was from November 2019 to November 2020.80 patients with advanced biliary tumor disease were enrolled.They were divided into groups according to the order of admission,with 40 cases in each group.The control group received oxaliplatin combined with gemcitabine,and the experimental group received oxaliplatin combined with tiggio.Incidence of adverse reactions,time to disease progression,survival time and clinical efficacy were checked and assessed.Results:Compared with the incidence of adverse reaction of the experimental group,which was 5.00%(2/40),the incidence of adverse reaction of the control group was 25.00%(10/40).The chi-square value=6.2745,p-value=0.0122.The time to progression and survival time of patients in the experimental group were shorter than those of the control group,with significant differences between the groups(p<0.05);the clinical efficacy of the experimental group and the control group were 97.50%(39/40)and 77.50%(31/40)respectively,the comparative chi-square value=7.3143,p-value=0.0068.Conclusion:The combined treatment of oxaliplatin and Tiggio in the treatment of advanced biliary tract tumors has higher safety and reduces the incidence of adverse reactions.

Clinical Study on Treatment to Ankylosing Spondylitis with Fengshi Qutong Capsule-Diclofenac Sodium Combination

Objective:To discuss the clinical study on Fengshi Qutong capsules combined with diclofenac sodium in the treatment of ankylosing spondylitis.Methods:80 patients who were treated for ankylosing spondylitis from June 2019 to June 2020 were selected and divided into two groups.The experimental group was treated with Fengshi Qutong capsules combined with diclofenac sodium,and the control group was treated with sulfasalazine enteric-coated tablets.Results:The treatment efficacy,VAS score,BASDAI score,BASFI score,CRP level,TNF-α level,IL-Iβ level,and the incidence of adverse reactions between the two groups were significantly different(P<0.05).Conclusion:The application of Fengshi Qutong capsules combined with diclofenac sodium in the treatment of patients with ankylosing spondylitis is beneficial to improve the treatment efficacy,reduce the levels of CRP,TNF-α,and IL-Iβ,reduce the incidence of adverse reactions,and reduce the VAS,BASDAI and BASFI scores,rendering it of important clinical value.

Stay in touch with the endoplasmic reticulum

The endoplasmic reticulum(ER),which is composed of a continuous network of tubules and sheets,forms the most widely distributed membrane system in eukaryotic cells.As a result,it engages a variety of organelles by establishing membrane contact sites(MCSs).These contacts regulate organelle positioning and remodeling,including fusion and fission,facilitate precise lipid exchange,and couple vital signaling events.Here,we systematically review recent advances and converging themes on ER-involved organellar contact.The molecular basis,cellular influence,and potential physiological functions for ER/nuclear envelope contacts with mitochondria,Golgi,endosomes,lysosomes,lipid droplets,autophagosomes,and plasma membrane are summarized.

A GMDA clustering algorithm based on evidential reasoning architecture

The traditional clustering algorithm is difficult to deal with the identification and division of uncertain objects distributed in the overlapping region,and aimed at solving this problem,the Evidential Clustering based on General Mixture Decomposition Algorithm(GMDA-EC)is proposed.First,the belief classification of target cluster is carried out,and the sample category of target distribution overlapping region is extended.Then,on the basis of General Mixture Decomposition Algorithm(GMDA)clustering,the fusion model of evidence credibility and evidence relative entropy is constructed to generate the basic probability assignment of the target and achieve the belief division of the target.Finally,the performance of the algorithm is verified by the synthetic dataset and the measured dataset.The experimental results show that the algorithm can reflect the uncertainty of target clustering results more comprehensively than the traditional probabilistic partition clustering algorithm.

Basic Research Advances in China on Embryo Implantation,Placentation,and Parturition

This review aimed to summarize the major progress in maternal-fetal medicine achieved by Chinese scientists in recent years.PubMed was systematically searched from January 2020 to November 2023.Publications that reported the progress in embryo implantation,placentation,and parturition made by Chinese scientists in the last 3 years were selected.The milestone events during gestation,embryo implantation,endometrial decidualization,placentation,and parturition are pivotal to a successful pregnancy.Embryo implantation requires intricate interactions between implantation-competent blastocysts and receptive endometrium.To adapt to pregnancy,endometrial stromal cells transform into specialized decidual cells,which occur spontaneously under the influence of ovarian hormones in humans but require the presence of embryos in mice.With embryonic development,the placenta forms to support fetal growth until parturition.The maternal-fetal interface is composed of diverse cell types,including endometrial decidual cells,placental trophoblast cells,endothelial cells,and various immune cells,a sophisticated interplay among which contributes to the maintenance of pregnancy.Near term,the uterus transitions from quiescence to contractility,in preparation for delivery.Disruptions to these events lead to pregnancy-related disorders such as repeated implantation failure,recurrent pregnancy loss,preeclampsia,fetal growth restriction,preterm birth,and infertility.In recent years,Chinese scientists have made prominent achievements in basic research on the aforementioned pregnancy events.Chinese scientists have made remarkable contributions to reproductive biology and maternal-fetal medicine research in recent years,highlighting future research directions in this field.