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A rapid point-of-care assay based on CRISPR-Cas13a for HBV was built with a LOD of 1 copy per μL was achieved in 50 min. The lateral flow test strip method can achieve naked-eye results, and the fluorescence readout can achieve real-time detection.

cervical cancer is the leading cause of cancer deaths in women in the developing world, with high-risk HPV16 and HPV18 accounting for approximately 70% of all cervical cancers. Early detection of HPV, especially high-risk HPV types, is essential to prevent disease progression.in this study, we established a highly sensitive and specific nucleic acid assay based on a CRISPR-Cas13a/Cas12a dual-channel system combined with multiplex RAA for rapid detection and typing of HPV16/18, which provides a new idea for cervical cancer screening. To meet the application of field testing, we designed a portable fluorescence imaging assay that can judge the test results directly with the naked eye or through cell phone imaging.the lower limit of detection for both HPV16 and HPV18 based on the CRISPR-Cas12a/Cas13a dual-channel assay was 10this developed portable dual gene assay platform may provide new technical support for cervical cancer screening in resource-limited settings.

In Vitro Diagnosis (IVD) technology is able to accurately detect pathogens or biomarkers at an initial stage of disease, which works as an important toolbox for disease diagnosis. Clustered regularly interspaced short palindromic repeats (CRISPR) and CRISPR-associated (Cas) system, as an emerging IVD method, plays a crucial role in the field of infectious disease detection due to its superior sensitivity and specificity. Recently, an increasing number of scientists have been devoted to improving the performance of CRISPR-based detection and on-site point-of-care testing (POCT) from extraction-free detection, amplification-free, modified Cas/crRNA complexes, quantitative assays, one-pot detection, and multiplexed platform. In this review, we describe the potential roles of these novel approaches and platforms in one-pot methods, quantitative molecular diagnostics as well as multiplexed detection. This review will not only help guide the full use of the CRISPR-Cas tools for quantification, multiplexed detection, POCT and as next-generation diagnostic biosensing platforms but also inspire new ideas, technological advances, and engineering strategies to address real-world challenges like the ongoing COVID-19 pandemic.

Rapid and accurate diagnostic methods are essential to interrupt outbreaks of infectious diseases such as COVID-19. However, the most commonly used nucleic acid detection method, qPCR or RT-qPCR, takes several hours to complete and requires highly sophisticated equipment. Recently, an emerging nucleic acid detection method based on the CRISPR/Cas system has reduced the reliance on qPCR. It has several important features that make it suitable for on-site POCT (point-of-care testing), including short detection cycles, low cost, high sensitivity, and the ability to be combined with different readout methods. This review briefly introduces the steps of CRISPR/Cas detection and then summarizes the current advances of CRISPR/Cas-based POCT from four steps: nucleic acid extraction, target amplification, CRISPR/Cas-based signal generation, and signal output. Finally, we discuss the advantages and challenges of CRISPR-based POCT and describe the future research perspectives for CRISPR.

CRISPR-Cas12a is a promising genome editing system for targeting AT-rich genomic regions. Comprehensive genome engineering requires simultaneous targeting of multiple genes at defined locations. Here, to expand the targeting scope of Cas12a, we screen nine Cas12a orthologs that have not been demonstrated in plants, and identify six, ErCas12a, Lb5Cas12a, BsCas12a, Mb2Cas12a, TsCas12a and MbCas12a, that possess high editing activity in rice. Among them, Mb2Cas12a stands out with high editing efficiency and tolerance to low temperature. An engineered Mb2Cas12a-RVRR variant enables editing with more relaxed PAM requirements in rice, yielding two times higher genome coverage than the wild type SpCas9. To enable large-scale genome engineering, we compare 12 multiplexed Cas12a systems and identify a potent system that exhibits nearly 100% biallelic editing efficiency with the ability to target as many as 16 sites in rice. This is the highest level of multiplex edits in plants to date using Cas12a. Two compact single transcript unit CRISPR-Cas12a interference systems are also developed for multi-gene repression in rice and Arabidopsis. This study greatly expands the targeting scope of Cas12a for crop genome engineering., CRISPR-Cas12a is a promising system for targeting AT-rich regions of the genome. Here the authors identify Cas12a orthologs with expanded targeting scope and develop a highly multiplexable editing system in rice.

The construction of public sports does not only improve the sports performance of college students, but also improves the health level of students. At present, the achievements of public sports construction in colleges and universities are not good, and the reasons for hindering the improvement of students’ physical health are more complex. In order to explore the problems existing in the construction of public sports in colleges and universities, this study used literature survey, the Delphi method, questionnaire survey and factor analysis to analyze the health impact mechanism of college students, and carried out intervention research according to analysis results. Factor analysis was used to extract the students’ factors, school factors, parents’ factors and social factors from the 30 influencing factors in the questionnaire and, through empirical analysis, it summed up the students’ health influence mechanism, such as learning pressure, physical education curriculum, family health attention and so on. In view of the main influencing factors, the targeted intervention, including improving the students’ and parents’ awareness of physical exercise and enhancing the load of physical education curriculum in colleges and universities is designed. Before and after the intervention, students’ sprint and long-distance running tests show that students’ physical fitness has been significantly improved, and the intervention results show that targeted intervention can promote the healthy development of college students. It is expected that this study can strengthen the level of public sports construction in colleges and universities, so as to improve students’ physical quality. RESUMO A construção de esportes públicos não só melhora o desempenho esportivo dos estudantes universitários, como também melhora o nível de saúde desses estudantes. Atualmente, as instalações esportivas em faculdades e universidades não são boas, e as razões para impedir a melhoria da saúde física dos estudantes são mais complexas. A fim de explorar os problemas existentes na construção de esportes públicos em faculdades e universidades, este estudo utilizou o método da literatura, o método Delphi, o método de levantamento por questionários e o método de análise de fatores para analisar o mecanismo de impacto na saúde dos estudantes universitários, e realizou pesquisas de intervenção de acordo com os resultados da análise. A análise de fatores foi usada para extrair os fatores dos alunos, fatores escolares, fatores dos pais e fatores sociais dos trinta fatores que influenciam o questionário, e através de análise empírica, resumiu-se o mecanismo de influência da saúde dos alunos, como pressão na aprendizagem, carga curricular de educação física, atenção à saúde familiar e assim por diante. Tendo em conta os principais fatores influenciadores, concebeu-se a intervenção visada, incluindo a melhoria da conscientização dos estudantes e dos pais para o exercício físico e o reforço da carga dos programas de educação física nas faculdades e universidades. Antes e depois da intervenção, o teste de sprint e de longa distância dos estudantes mostra que a aptidão física dos estudantes foi significativamente melhorada, e os resultados da intervenção mostram que a intervenção orientada pode promover o desenvolvimento saudável dos estudantes universitários. Espera-se que este estudo possa reforçar o nível de concepção dos serviços de públicos esportivos em faculdades e universidades, de modo a melhorar a qualidade física dos estudantes. RESUMEN La instalación de deportes públicos no solo mejora el rendimiento deportivo de los estudiantes universitarios, sino que también mejora el nivel de salud de los estudiantes. En la actualidad, los logros de la instalación de deportes públicos en colegios y universidades no son buenos y las razones que obstaculizan la mejora de la salud física de los estudiantes son más complejas. Con el fin de explorar los problemas existentes en la instalación de deportes públicos en colegios y universidades, este estudio utilizó la revisión de literatura, el método Delphi, la encuesta de cuestionario y el análisis factorial para analizar el mecanismo de impacto en la salud de los estudiantes universitarios, y llevó a cabo una investigación de intervención según los resultados de los análisis. Se utilizó el análisis factorial para extraer los factores de los estudiantes, los factores escolares, los factores de los padres y los factores sociales de los 30 factores de influencia del cuestionario y, a través del análisis empírico, se resumió el mecanismo de influencia de la salud de los estudiantes, como la presión de aprendizaje, plan de estudios de educación, atención de salud familiar, etc. Teniendo en cuenta los principales factores que influyen, se diseñó la intervención dirigida, incluida la mejora de la conciencia de los estudiantes y los padres sobre el ejercicio físico y la mejora de la carga del plan de estudios de educación física en los colegios y universidades. Antes y después de la intervención, las pruebas de carrera de velocidad y de larga distancia de los estudiantes muestran que la condición física de los estudiantes ha mejorado significativamente, y los resultados de la intervención muestran que la intervención dirigida puede promover el desarrollo saludable de los estudiantes universitarios. Se espera que este estudio pueda fortalecer el nivel de instalación de deportes públicos en colegios y universidades, de manera que mejore la calidad física de los estudiantes.

Summary CRISPR‐Cas9 is an emerging genome editing tool for reverse genetics in plants. However, its application for functional study of non‐coding RNAs in plants is still at its infancy. Despite being a major class of non‐coding RNAs, the biological roles of circle RNAs (circRNAs) remain largely unknown in plants. Previous plant circRNA studies have focused on identification and annotation of putative circRNAs, with their functions largely uninvestigated by genetic approaches. Here, we applied a multiplexed CRISPR‐Cas9 strategy to efficiently acquire individual null mutants for four circRNAs in rice. We showed each of these rice circRNA loci (Os02circ25329, Os06circ02797, Os03circ00204 and Os05circ02465) can be deleted at 10% or higher efficiency in both protoplasts and stable transgenic T0 lines. Such high efficiency deletion enabled the generation of circRNA null allele plants without the CRISPR‐Cas9 transgene in the T1 generation. Characterization of the mutants reveals these circRNAs’ participation in salt stress response during seed germination and in particular the Os05circ02465 null mutant showed high salt tolerance. Notably, the seedlings of the Os06circ02797 mutant showed rapid growth phenotype after seed germination with the seedlings containing higher chlorophyll A/B content. Further molecular and computational analyses suggested a circRNA–miRNA–mRNA regulatory network where Os06circ02797 functions to bind and sequester OsMIR408, an important and conserved microRNA in plants. This study not only presents genetic evidence for the first time in plants that certain circRNAs may serve as sponges to negatively regulate miRNAs, a phenomenon previously demonstrated in mammalian cells, but also provides important insights for improving agronomic traits through gene editing of circRNA loci in crops.

Background The incubation period is a crucial index of epidemiology in understanding the spread of the emerging Coronavirus disease 2019 (COVID-19). In this study, we aimed to describe the incubation period of COVID-19 globally and in the mainland of China. Methods The searched studies were published from December 1, 2019 to May 26, 2021 in CNKI, Wanfang, PubMed, and Embase databases. A random-effect model was used to pool the mean incubation period. Meta-regression was used to explore the sources of heterogeneity. Meanwhile, we collected 11 545 patients in the mainland of China outside Hubei from January 19, 2020 to September 21, 2020. The incubation period fitted with the Log-normal model by the coarseDataTools package. Results A total of 3235 articles were searched, 53 of which were included in the meta-analysis. The pooled mean incubation period of COVID-19 was 6.0 days (95% confidence interval [CI] 5.6–6.5) globally, 6.5 days (95% CI 6.1–6.9) in the mainland of China, and 4.6 days (95% CI 4.1–5.1) outside the mainland of China (P = 0.006). The incubation period varied with age (P = 0.005). Meanwhile, in 11 545 patients, the mean incubation period was 7.1 days (95% CI 7.0–7.2), which was similar to the finding in our meta-analysis. Conclusions For COVID-19, the mean incubation period was 6.0 days globally but near 7.0 days in the mainland of China, which will help identify the time of infection and make disease control decisions. Furthermore, attention should also be paid to the region- or age-specific incubation period. Graphic Abstract

Background The incubation period is a key index of epidemiology in understanding of the spread of infectious diseases and the decision-making of the disease control. However, the incubation period of the emerging COVID-19 is still unclear. Methods Between January 19, 2020 and September 21, 2020, we collected information on 11545 patients in Mainland China outside Hubei. The 218 patients with precise data was validation population. The incubation period was fitted with lognormal model by the coarseDataTools package in R. Results In 11545 patients, the mean incubation period of COVID-19 was 7.1 days (95% Confidence interval [CI], 7.0–7.2). About 5.4% of patients had precise incubation period less than 3 days, 10.2% longer than 14 days, and 2.1% longer than 21 days. There was no statistically significant difference in incubation period between male and female (P = 0.603). It was similar in the 218 patients. The mean accurate incubation period was 6.8 days (6.2–7.4). Of which, 14.7% (32/218) of patients had incubation period less than 3 days, 12.4% (27/218) longer than 14 days, and 0.9% (2/218) longer than 21 days. Conclusions For COVID-19, the mean incubation period is 7.1 days and 10.2% of patients developed disease 14 days after infection, which challenges the current 14-day quarantine strategy.

The laser marking system was combined with MES system, the marking setting database was established by sorting out the product specifications, and the products of various specifications were quickly matched by calling the template, so as to realize the control automation of the product marking system and reduce the difficulty of processing non-standard products. Using image recognition technology, the marking area and the marking effect are digitized, the quality monitoring visual window is established, and the backup is stored in the MES system, so that the quality is controllable and can be checked in the later stage. The laser marking system introduced in this paper reduces manual intervention in production data to the greatest extent, improves the accuracy of information, sorts out various types and specifications of products, and sets up marking templates accordingly, which greatly improves the efficiency of cable network production. Finally, image recognition technology is applied to quality control to realize quality management and record, which provides reference for other production and processing system design.

Inter-provincial market trading is putting up with to implement the national energy strategy, increasing clean energy consuming and optimization energy allocation in large-scale. To promote energy consumption, the inter-province power transmission channel’ potential needs to be full excavate to deal with clean energy fluctuation, improving trading frequency and reduce transaction period. This article puts up with an inter-province power market trading space calculation method to calculate the available power transmission ability of inter-provincial transmission channel, discovering transmission channel and releasing transaction space. Besides, for certain transmission channel or supply-demand province’s electricity requirements, the calculation method can explore the trading market space, organizing clean energy evacuation to improve transmission channel utilization and safety checking pass rates, reducing blocking.

In vitro and in vivo interactions of minocycline and azoles, including itraconazole, voriconazole, and posaconazole, against filamentous pathogenic fungi were investigated. A total of 56 clinical isolates were studied in vitro via broth microdilution checkerboard technique, including 20 strains of Aspergillus fumigatus, 7 strains of Aspergillus flavus, 16 strains of Exophiala dermatitidis, 10 strains of Fusarium solani, and 3 strain s of Fusarium oxysporum. The results revealed that minocycline did not exhibit any significant antifungal activity against any of the tested strains. However, favorable synergy of minocycline with itraconazole, voriconazole, or posaconazole was observed against 34 (61%), 28 (50%), and 38 (68%) isolates, respectively, including azole-resistant A. fumigatus and Fusarium spp. with inherently high MICs of azoles. Synergistic combinations resulted in 4-fold to 16-fold reduction of effective MICs of minocycline and azoles. No antagonism was observed. In vivo effects of minocycline-azole combinations were evaluated by survival assay in a Galleria mellonella model infected with E. dermatitidis strain BMU00034; F. solani strain FS9; and A. fumigatus strains AF293, AFR1, and AFR2. Minocycline acted synergistically with azoles and significantly increased larvae survival in all isolates (P

Two recently engineered SpCas9 variants, namely xCas9 and Cas9-NG, show promising potential in improving targeting specificity and broadening the targeting range. In this study, we evaluated these Cas9 variants in the model and crop plant, rice. We first tested xCas9-3.7, the most effective xCas9 variant in mammalian cells, for targeted mutagenesis at 16 possible NGN PAM (protospacer adjacent motif) combinations in duplicates. xCas9 exhibited nearly equivalent editing efficiency to wild-type Cas9 (Cas9-WT) at most canonical NGG PAM sites tested, whereas it showed limited activity at non-canonical NGH (H = A, C, T) PAM sites. High editing efficiency of xCas9 at NGG PAMs was further demonstrated with C to T base editing by both rAPOBEC1 and PmCDA1 cytidine deaminases. With mismatched sgRNAs, we found that xCas9 had improved targeting specificity over the Cas9-WT. Furthermore, we tested two Cas9-NG variants, Cas9-NGv1 and Cas9-NG, for targeting NGN PAMs. Both Cas9-NG variants showed higher editing efficiency at most non-canonical NG PAM sites tested, and enabled much more efficient editing than xCas9 at AT-rich PAM sites such as GAT, GAA, and CAA. Nevertheless, we found that Cas9-NG variants showed significant reduced activity at the canonical NGG PAM sites. In stable transgenic rice lines, we demonstrated that Cas9-NG had much higher editing efficiency than Cas9-NGv1 and xCas9 at NG PAM sites. To expand the base-editing scope, we developed an efficient C to T base-editing system by making fusion of Cas9-NG nickase (D10A version), PmCDA1, and UGI. Taken together, our work benchmarked xCas9 as a high-fidelity nuclease for targeting canonical NGG PAMs and Cas9-NG as a preferred variant for targeting relaxed PAMs for plant genome editing.

Hepatitis B remains a major global public health challenge, with particularly high prevalence in medically disadvantaged western Pacific and African regions. Although clinically available technologies for the qPCR detection of HBV are well established, research on point-of-care testing has not progressed substantially. The development of a rapid, accurate point-of-care test is essential for the prevention and control of hepatitis B in medically disadvantaged rural areas. The development of the CRISPR/Cas system in nucleic acid detection has allowed for pathogen point-of-care detection. Here, we developed a rapid and accurate point-of-care assay for HBV based on LAMP-Cas12a. It innovatively solves the problem of point-of-care testing in 10 min, particularly the problem of sample nucleic acid extraction. Based on LAMP-Cas12a, visualization of the assay results is presented by both a fluorescent readout and by lateral flow test strips. The lateral flow test strip technology can achieve results visible to the naked eye, while fluorescence readout can achieve real-time high-sensitivity detection. The fluorescent readout-based Cas12a assay can achieve HBV detection with a limit of detection of 1 copy/μL within 13 min, while the lateral flow test strip technique only takes 20 min. In the evaluation of 73 clinical samples, the sensitivity and specificity of both the fluorescence readout and lateral flow test strip method were 100%, and the results of the assay were fully comparable to qPCR. The LAMP-Cas12a-based HBV assay relies on minimal equipment to provide rapid, accurate test results and low costs, providing significant practical value for point-of-care HBV detection.

With the development of computer technology, higher education reforms have made better progress. After the application of computer technology is mature, colleges and universities begin to use computer network distance courses to expand students’ learning resources and learning horizons. This paper mainly focuses on the application and reform influence of network distance teaching in physical education.

This paper proposes the analysis model of sports human body based on computer vision tracking technology. Visual target tracking is an important research field of the computer vision, motion trajectory and it can provide not only the goal, to provide the initial data movement analysis, scene understanding, behavior or the event detection in intelligent surveillance, human-computer interaction, robot visual navigation and motion recognition based on field has a broad application prospect. For this reason, it is possible to consider the use of a large number of unlabeled samples to assist the training classifier to improve its performance. This type of machine learning method using both labeled and that unlabeled samples is called the semi-supervised learning. This paper proposes the novel idea of the related research topics to propose the new perspective of the model that will be later give us the novel idea of making it efficient for further development of sport science.

In order to study the influence of physical exercise on the secretion of serum leptin in patients with obesity, some experts searched Wanfang database, www.edu.cn, Pubmed, Web of Science, Google Scholar, Cochrane Library and other databases, and they found and carefully studied 92 qualified articles and 346 pairs of intervention data. Judgment method: use a special method to calculate the effect value of each group of retrieved data, then calculate the weight through the standard deviation of the data, then calculate the average weight, and finally get the 95% confidence interval value. When this interval value is greater than or equal to zero, it means through the form of sports has no effect on blood thin; and when the value is less than 0 means that the sport's influence on blood thin element was significantly larger. That is to say the effect of the absolute value of difference, the greater the impact on blood thin element is the more obvious, and vice versa. Due to the obvious difference of effect value brought by different exercise amount on human body, the change of serum leptin in patients can be determined by the difference of effect value.

Electrochemical and spectroelectrochemical properties of three open-chain pentapyrroles and the corresponding sapphyrins were examined in pyridine containing 0.1 M tetra-n-butylammonium perchlorate and dichloromethane (CH2Cl2) or benzonitrile (PhCN) containing tetra-n-butylammonium hydroxide (TBAOH). The investigated compounds are represented as (Ar)4PPyH3 and (Ar)4SH3, where Ar is a F(-) or Cl(-) substituted phenyl group, PPy is a trianion of the open-chain pentapyrrole, and S is a trianion of the sapphyrin. The pentapyrroles, (Ar)4PPyH3, undergo two reversible one-electron reductions in pyridine, while the structurally related sapphyrins exhibit four reductions in this solvent, the first two of which are irreversible due to coupled chemical reactions following the electron transfers. Both series of neutral compounds could be deprotonated in CH2Cl2 or PhCN by addition of TBAOH to solution, and the progress of these reactions was monitored as a function of the base concentration by cyclic voltammetry and UV-vis spectroscopy. The neutral pentapyrroles were spectroscopically shown to undergo a loss of two protons in a single step to generate the [(Ar)4PPyH](2-) dianion while the sapphyrins could only be monodeprotonated, leading to formation of the [(Ar)4SH2](-) monoanion under the same solution conditions. The deprotonation constants were measured for each series of compounds in benzonitrile, and oxidation-reduction mechanisms are examined as a function of the solution 'basicity'.

Open-chain pentapyrroles were isolated as side-products from the synthesis of triaryl-corroles and then converted to the corresponding sapphyrins by catalytic oxidation in acidic media. The investigated compounds were characterized by UV-vis and (1)H NMR spectroscopy, mass spectrometry, electrochemistry, and spectroelectrochemistry and are represented as (Ar)4PPyH3 and (Ar)4SH3, where Ar is a F(-) or Cl(-) substituted phenyl group, PPy is a trianion of the open-chain pentapyrrole, and S is a trianion of the sapphyrin. Cyclic voltammetry and thin-layer UV-vis spectroelectrochemistry measurements were carried out in PhCN and CH2Cl2 containing 0.1 M tetra-n-butylammonium perchlorate. The open-chain pentapyrroles undergo two reversible one-electron reductions and two reversible one-electron oxidations to generate [(Ar)PPyH3](-), [(Ar)PPyH3](2-), [(Ar)PPyH3](+), and [(Ar)PPyH3](2+) which were spectroscopically characterized. The corresponding sapphyrins exhibit two or three reversible one-electron oxidations in PhCN, but the reductions of these compounds are irreversible because of coupled chemical reactions following electron transfer. Comparisons are made between redox potentials and spectral properties of the open-chain pentapyrroles, sapphyrins, and structurally related corroles. Protonation of the open-chain pentapyrroles and sapphyrins was also carried out in CH2Cl2, and equilibrium constants were calculated by monitoring the spectral changes during titrations with trifluoroacetic acid. The pentapyrroles undergo a simultaneous two-proton addition to generate [(Ar)4PPyH5](2+) while the sapphyrins undergo two stepwise single proton additions to give [(Ar)4SH4](+) and [(Ar)4SH5](2+), respectively.

Two meso-dichlorophenyl substituted metallocorroles were synthesized and characterized as to their electrochemical and spectroelectrochemical properties in dichloromethane, benzonitrile, and pyridine containing 0.1 M tetra-n-butylammonium perchlorate (TBAP) as supporting electrolyte. The examined compounds are represented as (Cl2Ph)3CorFeIVCl and (Cl2Ph)3CorMnIVCl where (Cl2Ph)3Cor is the trianion of 5,10,15-tri(2,4-dichlorophenyl)corrole. Each metallocorrole was examined as to its catalytic activity for the electoreduction of dioxygen when coated on an edge-plane pyrolytic graphite electrode in 1.0 M HClO4. Cyclic voltammetry combined with linear sweep voltammetry at a rotating disk electrode (RDE) and a rotating ring disk electrode (RRDE) was utilized to evaluate the catalytic activity for the electroreduction of O2. The main O2 reduction product is hydrogen peroxide under the given experimental conditions.

Cascading trips caused by flow transferring is the crucial causation of many well-known blackouts. This paper confirms the research object and proposes he prerequisite of flow transferring identification. According to the basic characteristics of the fault dynamic process, this paper proposes a flow transferring identification scheme based on local information. The scheme does not rely on communication and makes a fast conclusion. It also considers the factors including system oscillation, evolved faults, converted faults and so on, which affect the result of flow transferring identification. It is quite suitable for asymmetrical flow transferring identification. PSCAD/EMTDC simulation results show the effectiveness of the scheme.