Design and Experiments of the High Voltage Pulsed Electric Fields Sterilization System

This experiment designed the pulsed electric fields （PEF） of high intensity of 100 kV· cm^-1 sterilization system. Fluorescent pseudomonas as target cell was operated 180 s in the PEF. By observing the difference of the bacteria before and after the disposal by TEM, it is found that the cell walls of the treated bacteria were broken. Irreversible perforations were formed on the cell membrane. The cell inclusions and cell fragments were leaked. The cell died as a result. The results showed that the PEF sterilization system designed can be used for liquid food sterilization experiments.

Verification of Drainage Sterilization System Uses Low-Voltage Pulsed Electric Field in a Prawn Farm

It is necessary to take measures against infectious diseases in the Southeast Asian prawn farming industry. In giant tiger prawn （Penaeus monodon） aquaculture, diseases caused by viruses such as white spot syndrome virus （WSSV） and bacteria such as Vibrio have become a menace. Appropriate treatments of prawn culture pond＇s waters are advocated for preventing and controlling pathogens. The purpose of this study was to conduct an antimicrobial water treatment using a low-voltage pulsed electric field sterilization. Here we prepared a mechanical low-voltage pulsed electric field system with copper wire coiling around a titanium ring. The viability of WSSV in seawater was examined by prawn infectivity experiments. We inoculated healthy prawns （approximately 10-15 g） with the WSSV master sample that passed 0-3 times through the system. WSSV infection in prawns decreased according to the number of passes through the system. Healthy prawns survived for〉 10 days without feeding, where as prawns inoculated with the WSSV master sample showed symptoms of white spot and died in about 4 days. Two-thirds of the prawns inoculated with the WSSV master sample that was passed once through the system developed WSSV symptoms and were polymerase chain reaction （PCR） positive. However, no symptoms were observed and prawns were PCR negative when the WSSV master sample was passed three times through the system. Based on these results, we purpose that a low-voltage pulsed electric field system will serve as an efficient pond drainage sterilization system and will replace conventional treatments using chemicals such as sodium hypochlorite.

A Novel Aircraft Air Conditioning System with a Sterilization Unit by Ultra-High-Temperature Air Stream

An aircraft cabin is a narrow,closed-space environment.To keep the air quality in cabin healthy for passengers,especially during an epidemic such as SARS-CoV-2(or 2019-nCoV)in 2020,a novel aircraft air conditioning system,called the ultra-high-temperature instantaneous sterilization air conditioning system(UHTACS),is proposed.Based on the proposed system,a simulation of the UHT-ACS is analysed in various flight states.In the UHT-ACS,the mixing air temperature of return and bleed air can reach temperature up to 148.8°C,which is high enough to kill bacilli and viruses in 2一8 s.The supply air temperature of the UHT-ACS in a mixing cavity is about 12 C in cooling mode both on the ground and in the air.The supply air temperature is about 42 C in heating mode.Compared with the air conditioning systems(ACS)of traditional aircraft the supply air temperatures of the UHT-ACS in the mixing cavity are in good agreement with those of a traditional ACS with 60%fresh air and 40%return air.Furthermore the air temperature at the turbine outlet of the UHT-ACS is higher than that of a traditional ACS which will help to reduce the risk of icing at the outlet.Therefore the UHT-ACS can operate normally in various flight states.

Improve the Center Supply Room to Ensure the Quality System for Disinfection and Sterilization

The disinfection supply room is a very important department of the hospital.Its main job is to provide sterile equipment and dressings for various activities in the hospital.It is an important department in the hospital infection management process.Doing a good job in the control and management of the disinfection supply room is the main link to ensure the prevention and control of hospital infections.The quality of management directly affects modern clinical medical work.Therefore,the hospital supply room should be strengthened and improved to ensure that all items can be safely used in the work process,which can effectively avoid the occurrence of cross-infection incidents in the hospital.

Improving plasma sterilization by constructing a plasma photocatalytic system with a needle array corona discharge and Au plasmonic nanocatalyst

Efficient sterilization by a plasma photocatalytic system(PPS)requires strong synergy between plasma and photocatalyst to inactivate microorganisms while suppressing the formation of secondary pollutants.Here,we report that a PPS constructed from a needle array corona discharge and Au/TiO2plasmonic nanocatalyst could remarkably improve the sterilization of Escherichia coli(E.coli)and alleviate formation of the discharge pollutant O3.At 6 kV,the combination of corona discharge and Au/TiO2achieves sterilization efficiency of 100%within an exposure time of 5 min.At 5 kV and an exposure time of 8 min,the presence of Au/TiO2improves sterilization efficiency of the corona discharge from 73%to 91%and reduces the O3concentration from 0.38 to 0.04 ppm,whereas the presence of TiO2reduces the sterilization efficiency and O3concentration to 66%and 0.17 ppm,respectively.The Au/TiO2in the PPS enables a uniform corona discharge,enhances the interaction between plasma,E.coli and nanocatalysts,and suppresses the formation of O3.Further,the Au/TiO2can be excited by ultraviolet-visible light emitted from the plasma to generate electron-hole pairs,and thus contributes to the formation of reactive radicals and the oxidative inactivation of E.coli.The PPS constructed from a needle array corona discharge and Au-based plasmonic nanocatalyst provides a promising approach for developing high-efficiency sterilization techniques.

Evaluation of the Impact of Refined Quality Control Management Model on the Qualified Rate of Disinfection and Sterilization of Surgical Instruments in the Sterilization Supply Center

Objective:To evaluate the application value of a refined quality control management model for a sterilization supply center.Methods:A retrospective analysis was conducted on the work situation of the sterilization supply center from January 2021 to January 2023.The work situation before January 31,2022,was classified as the control group;a routine quality control management model was implemented,and the work situation after January 31,2022,was classified as the observation group.The quality of medical device management and department satisfaction between the two groups were compared.Results:The timely recovery and supply rate,classification and cleaning pass rate,disinfection pass rate,packaging pass rate,sterilization pass rate,and department satisfaction score in the observation group were all higher than those of the control group(P<0.05).Conclusion:Implementing a refined quality control management model in the sterilization supply center can improve the quality management level of medical devices and department satisfaction and is worthy of promotion.

A novel Ag/ZnO core-shell structure for efficient sterilization synergizing antibiotics and subsequently removing residuals

The massive use of antibiotics has led to the aggravation of bacterial resistance and also brought environmental pollution problems.This poses a great threat to human health.If the dosage of antibiotics is reduced by increasing its bactericidal performance,the emergence of drug resistance is certainly delayed,so that there's not enough time for developing drug resistance during treatment.Therefore,we selected typical representative materials of metal Ag and semiconductor ZnO nano-bactericides to design and synthesize Ag/ZnO hollow core-shell structures(AZ for short).Antibiotics are grafted on the surface of AZ through rational modification to form a composite sterilization system.The research results show that the antibacterial efficiency of the composite system is significantly increased,from the sum(34.7%+22.8%-57.5%)of the antibacterial efficiency of AZ and gentamicin to 80.2%,net synergizes 22.7%,which fully reflects the effect of 1+1>2.Therefore,the dosage of antibiotics can be drastically reduced in this way,which makes both the possibility of bacterial resistance and medical expenses remarkably decrease.Subsequently,residual antibiotics can be degraded under simple illumination using AZ-self as a photocatalyst,which cuts off the path of environmental pollution.In short,such an innovative route has guiding significance for drug resistance.

FPGA-based plasma sterilization device for wound-edge recognition

There is a currently a lack of large-area plasma sterilization devices that can intelligently identify the shape of a wound for automatic steriliza-tion.For this reason,in this work,a plasma sterilization device with wound-edge recognition was developed using afield-programmable gate array(FPGA)and a high-performance image-processing platform to realize intelligent and precise sterilization of wounds.SOLIDWORKS was used to design the mechanical structure of the device,and it was manufactured using 3D printing.The device used an improvement of the traditional Sobel detection algorithm,which extends the detection of edges in only the x and y directions to eight directions(0○,45○,90○,135○,180○,225○,270○,and 315○),completing the wound-edge detection by adaptive thresholding.The device can be controlled according to different shapes of sterilization area to adjust the positioning of a single plasma-jet tube in the horizontal plane for two-dimensional move-ment;the distance between the plasma-jet tube and the surface of the object to be sterilized can be also adjusted in the vertical direction.In this way,motors are used to move the plasma jet and achieve automatic,efficient,and accurate plasma sterilization.It was found that a good sterilization effect could be achieved at both the culture-medium level and the biological-tissue level.The ideal sterilization parameters at the culture-medium level were a speed of 2 mm/s and aflow rate of 0.6 slm,while at the biological-tissue level,these values were 1 mm/s and 0.6 slm,respectively.

Effect of power supply parameters on discharge characteristics and sterilization efficiency of magnetically driven rotating gliding arc

Plasma sterilization is a new generation of high-tech sterilization method that is fast,safe,and pollution free.It is widely used in medical,food,and environmental protection fields.Home air sterilization is an emerging field of plasma application,which puts higher requirements on the miniaturization,operational stability,and operating cost of plasma device.In this study,a novel magnetically driven rotating gliding arc(MDRGA)discharge device was used to sterilize Lactobacillus fermentation.Compared with the traditional gas-driven gliding arc,this device has a simple structure and a more stable gliding arc.Simulation using COMSOL Multiphysics showed that adding permanent magnets can form a stable magnetic field,which is conducive to the formation of gliding arcs.Experiments on the discharge performance,ozone concentration,and sterilization effect were conducted using different power supply parameters.The results revealed that the MDRGA process can be divided into three stages:starting,gliding,and extinguishing.Appropriate voltage was the key factor for stable arc gliding,and both high and low voltages were not conducive to stable arc gliding and ozone production.In this experimental setup,the sterilization effect was the best at 6.6 kV.A high modulation duty ratio was beneficial for achieving stable arc gliding.However,when the duty ratio exceeded a certain value,the improvement in the sterilization effect was slow.Therefore,considering the sterilization effect and energy factors comprehensively,we chose 80%as the optimal modulation duty ratio for this experimental device.

Sterilization Effect of Cooking Process for Guilin Rice Noodles Based on Heat Conduction Model

Guilin rice noodles, a unique cuisine from Guilin, Guangxi, is renowned both domestically and internationally as one of the top ten “Guilin Classics”. Utilizing a heat conduction model, this study explores the effectiveness of the cooking process in sterilizing Guilin rice noodles before consumption. The model assumes that a large pot is filled with boiling water which is maintained at a constant high temperature heat resource through continuous gentle heating. And the room temperature is set as the initial temperature for the preheating process and the final temperature for the cooling process. The objective is to assess whether the cooking process achieves satisfactory sterilization results. The temperature distribution function of rice noodle with time is analytically obtained using the separation of variables method in the three-dimensional cylindrical coordinate system. Meanwhile, the thermal diffusion coefficient of Guilin rice noodles is obtained in terms of Riedel’ theory. By analyzing the elimination characteristics of Pseudomonas cocovenenans subsp. farinofermentans, this study obtains the optimal time required for effective sterilization at the core of Guilin rice noodles. The results show that the potential Pseudomonas cocovenenans subsp. farinofermentans will be completely eliminated through continuously preheating more than 31 seconds during the cooking process before consumption. This study provides a valuable reference of food safety standards in the cooking process of Guilin rice noodles, particularly in ensuring the complete inactivation of potentially harmful strains such as Pseudomonas cocovenenans subsp. farinofermentans.

Risk Assessment of Hydrogen Peroxide Low- Temperature Plasma Sterilization Using Different Monitoring Methods

Objective:This study aims to evaluate the application value of biological monitoring and different types of chemical indicator cards in batch monitoring of hydrogen peroxide low-temperature plasma sterilization.The goal is to standardize the selection of loading conditions for this sterilization method and avoid positive biological monitoring results.Methods:Physical monitoring,Class I chemical indicator card monitoring,Class IV chemical indicator card monitoring,and biological monitoring were used to monitor the hydrogen peroxide low-temperature plasma sterilization process.The sterilization effect on instruments inside the Johnson&Johnson 100S plasma sterilizer was monitored and the qualification of various monitoring methods was compared.Results:The comparison showed that when non-standard or adsorption-prone packaging materials were used,the interception rate of biological monitoring and Class IV chemical indicator cards was significantly higher than that of physical monitoring and Class I chemical indicator cards.These methods more intuitively and effectively detected sterilization failures.Conclusion:Biological monitoring and Class IV chemical indicator cards are safe,fast,accurate,and easy to interpret in hydrogen peroxide low-temperature plasma sterilization,especially for monitoring instruments inside packages.They provide a reliable basis for the release of sterilized instrument packages.Identifying the reasons for positive biological monitoring results in hydrogen peroxide low-temperature plasma sterilization and taking effective measures promptly can minimize associated risks.

Study on Explants Sterilization and Callus Induction of Aquilegia oxysepala

[Objective] The aim was to study the explants sterilization and callus induction of Aquilegia oxysepala.[Method] the seeds of Aquilegia oxysepala were sterilized by different kinds and concentrations of disinfectants,and the pollution rate and pollution speed were investigated so as to find the best way to build sterile seedling setup.Taking the roots,stem segments and leaves of the sterile seedlings from Aquilegia oxysepala seeds as explants,the optimum explants and medium were screened by adding MS basic medium with different hormone proportions.[Result] The best germicidal treatment was as follows：explants were soaked in 75% alcohol for 30 s firstly,washed by sterile water for 5 times,then soaked in 0.2% mercuric chloride liquid for 2 min,finally washed by sterile water for 5 times again.The sterilization treatment could get the lowest pollution rate,the highest germinating capacity and the best sterile seedling.Roots were the optimum explants for the callus induction of Aquilegia oxysepala,meanwhile the optimal medium was MS＋0.6 mg/L 2,4-D＋0.5 mg/L 6-BA.[Conclusion] The research provides technical support for the large scale production of Aquilegia oxysepala and also makes a contribution to the medicinal and ornamental value of Aquilegia oxysepala.

Transcriptional Regulation of 10 Mitochondrial Genes in Different Tissues of NCa CMS System in Brassica napus L. and Their Relationship with Sterility

Northern blot analysis was conducted with mitochondrial RNA from seedling leaves, floral buds, and developing seeds of NCa CMS, maintainer line and fertile F1 using ten mitochondrial genes as probes. The results revealed that 9 out of the 10 mitochondrial genes, except for atp6, showed no difference in different tissues of the corresponding materials of NCα CMS system and that they might be constitutively expressed genes. Eight genes, such as orf139, orf222, atpl, cox1, cox2, cob, rm5S, and rm26S, showed no difference among the three tissues of all the materials detected. So the expression of these eight genes was not regulated by nuclear genes and was not tissue-specific. The transcripts of atp9 were identical among different tissues, but diverse among different materials, indicating that transcription of atp9 was neither controlled by nuclear gene nor tissue-specific. Gene atp6 displayed similar transcripts with the same size among different tissues of all the materials but differed in abundance among tissues of corresponding materials and its expression might be tissue-specific under regulation of nuclear gene. Moreover, three transcripts of orf222 were detected in the floral buds of NCa cms and fertile F1, but no transcript was detected in floral buds of the maintainer line.The transcription of orf139 was similar to that of orf222 but only two transcripts of 0.8 kb and 0.6 kb were produced. The atp9 probe detected a single transcript of 0.6 kb in NCa cms and in maintainer line and an additional transcript of 1.2 kb in fertile F1. The relationship of expression of orf222, orf139, and atp9 with NCa sterility was discussed.

Sterilization Effect on Microorganisms by High Electrostatic Voltage

利用静电高压在室温条件下做了两种细菌和一种真菌(金黄色葡萄球菌,绿脓杆菌和白色念珠菌)的灭菌实验。实验中用了星形线和芒刺极两种电极结构,研究了这三种菌的存活率与电压、电晕功率和处理时间的关系。作者等也研究了正、负高压。正、负脉冲高压和交流高压对灭菌效果的影响。实验结果表明,适当选取条件,这三种菌完全可被电晕放电场杀死。静电灭菌是一种新方法,到目前为止,特别是对非液体物质的静电灭菌,尚未见报道。尽管这一技术还需进一步研究,但它为寻找新的灭菌途径提供了可能。

Establishment on Isolated Microspore Culture Optimized System for Restorer of New Cytoplasmic Male Sterile (NER) of Brassica napus L.

[Objective]The aim was to establish optimized system for NER isolated microspore culture of Brassica napus L.. [Method]Twenty varieties of NER of Brassica napus were grown under uncontrolled temperature and light conditions,and their isolated microspore from anthers were used as explants in vitro culture. The influencing factors of microspore culture were preliminarily studied. [Result]The difference of genotypes was important influencing factors to embryoid yield. The embryoid yield increased by supplementing with 6-BA and NAA,culturing in solid-liquid double layer medium with activated charcoal; The difference was not significant of embryoid yield between culturing in medium supplemented with colchicines and the CK. The rates of cotyledonous embryoids directly developed into normal plantlets increased through enriching with 0.1-0.2 mg/L NAA and being treated on slim illumination two days before being inducted into normal plantlets. [Conclusion]The technical system of microspore culture of restorer of new cytoplasmic male sterile （NER） was established,which and lays a foundation for accelerating genotype purification of NER introgressive line.

The Sterilization Technology of Medicinal Flowers

This paper reviewed the latest progress on the sterilization technology of medicinal flowers, and briefly introduced its principle and application. Compared with the traditional chemical sterilization and autoclave sterilization techniques, irradiation sterilization, light radiation sterilization and gas sterilization own their unique advan- tages for different drugs sterilization requirements, which are worth further promotion.

Radiation sterilization of tissue allografts:A review

Tissue substitutes are required in a number of clinical conditions for treatment of injured and diseased tissues.Tissues like bone,skin,amniotic membrane and soft tissues obtained from human donor can be used for repair or reconstruction of the injured part of the body.Allograft tissues from human donor provide an excellent alternative to autografts.However,major concern with the use of allografts is the risk of infectious disease transmission.Therefore,tissue allografts should be sterilized to make them safe for clinical use.Gamma radiation has several advantages and is the most suitable method for sterilization of biological tissues.This review summarizes the use of gamma irradiation technology as an effective method for sterilization of biological tissues and ensuring safety of tissue allografts.

CRISPR/Cas9-mediated multiple gene editing in Brassica oleracea var.capitata using the endogenous tRNA-processing system

Cabbage(Brassica oleracea var.capitata)is a biennial plant with strong self-incompatibility and an obligate requirement for prolonged vernalization by exposure to low temperatures to induce flowering.These characteristics significantly increase the difficulty of exploiting novel germplasm induced by physical or chemical mutagens.In this study,we report a CRISPR/Cas9 gene-editing system based on endogenous tRNA processing to induce high efficiency and inheritable mutagenesis in cabbage.Using the phytoene desaturase gene BoPDS,the S-receptor kinase gene BoSRK,and the male-sterility-associated gene BoMS1 as the target genes,multisite and multiple gene mutations were achieved using a construct with tandemly arrayed tRNA-sgRNA architecture to express multiple sgRNAs.The BoSRK3 gene mutation suppressed self-incompatibility completely,converting the self-incompatible line into a self-compatible line.In addition,the BoMS1 gene mutation produced a completely male-sterile mutant,which was highly cross compatible with its nonmutant isoline at the flowering stage as a result of a simultaneous BoSRK3 gene mutation,enabling the economic propagation of the male-sterile line through bee-mediated cross-pollination.Interestingly,higher site mutation efficiency was detected when a guide sequence was inserted into a location in the tandemly arrayed tRNA-sgRNA architecture that was distal from the upstream Pol III promoter.In addition,mutation sites were also detected in the paralogous genes of the BoPDS and BoSRK genes that had fully consistent sequences or base mismatches but beyond the“seed”region in the spacer sequence compared with the target sgRNAs.Collectively,our results demonstrate that the CRISPR/Cas9 system,coupled with an endogenous tRNA-processing system,is an efficient tool to improve cabbage traits.

Generation of male-sterile soybean lines with the CRISPR/Cas9 system

Soybean [Glycine max(L.) Merr.] provides a rich source of plant protein and oil worldwide. The commercial use of transgenic technology in soybean has become a classical example of the application of biotechnology to crop improvement. Although genetically modified soybeans have achieved commercial success,hybrid soybean breeding is also a potential way to increase soybean yield. Soybean cytoplasmic malesterile(CMS) lines have been used in three-line hybrid breeding systems, but their application to exploiting soybean heterosis has been limited by rare germplasm resource of sterile lines. The generation of various genetic diversity male-sterile soybean lines will help to overcome the shortcoming. In this study,we used targeted editing of AMS homologs in soybean by CRISPR/Cas9 technology for the first time to generate stable male-sterile lines. Targeted editing of GmAMS1 resulted in a male-sterile phenotype,while editing of GmAMS2 failed to produce male-sterile lines. GmAMS1 functions not only in the formation of the pollen wall but also in the controlling the degradation of the soybean tapetum.CRISPR/Cas9 technology could be used to rapidly produce stable male-sterile lines, providing new sterile-line materials for soybean hybrid breeding systems.

Effects of sterilization treatments on the analysis of TOC in water samples

Decomposition experiments conducted with and without microbial processes are commonly used to study the effects of environmental microorganisms on the degradation of organic pollutants.However,the effects of biological pretreatment （sterilization） on organic matter often have a negative impact on such experiments.Based on the principle of water total organic carbon （TOC） analysis,the effects of physical sterilization treatments on determination of TOC and other water quality parameters were investigated.The results revealed that two conventional physical sterilization treatments,autoclaving and 60 Co γ-radiation sterilization,led to the direct decomposition of some organic pollutants,resulting in remarkable errors in the analysis of TOC in water samples.Furthermore,the extent of the errors varied with the intensity and the duration of sterilization treatments.Accordingly,a novel sterilization method for water samples,0.45 μm micro-filtration coupled with ultraviolet radiation （MCUR）,was developed in the present study.The results indicated that the MCUR method was capable of exerting a high bactericidal effect on the water sample while significantly decreasing the negative impact on the analysis of TOC and other water quality parameters.Before and after sterilization treatments,the relative errors of TOC determination could be controlled to lower than 3% for water samples with different categories and concentrations of organic pollutants by using MCUR.