Dynamic microtubules are essential for efficient chromosome capture and biorientation in S. cerevisiae

Attachment of chromosomes to the mitotic spindle has been proposed to require dynamic microtubules that randomly search three-dimensional space and become stabilized upon capture by kinetochores. In this study, we test this model by examining chromosome capture in Saccharomyces cerevisiae mutants with attenuated microtubule dynamics. Although viable, these cells are slow to progress through mitosis. Preanaphase cells contain a high proportion of chromosomes that are attached to only one spindle pole and missegregate in the absence of the spindle assembly checkpoint. Measurement of the rates of chromosome capture and biorientation demonstrate that both are severely decreased in the mutants. These results provide direct evidence that dynamic microtubules are critical for efficient chromosome capture and biorientation and support the hypothesis that microtubule search and capture plays a central role in assembly of the mitotic spindle

Pricing of foreign exchange rate and interest rate risks using short to long horizon returns

Copyright © 2021 The Author(s). In this paper, we test whether foreign exchange (FX) rate and interest rate (IR) risks are priced at short to long return horizons. We also test whether the associated risk premia relate to certain stock characteristics. Our new evidence indicates that risk premia increase with the length of the return horizon and that the risk premium signs depend on the sign of the corresponding exposure beta. Thus, for our longest return horizon of 950 days, positive (negative) FX rate premia increase in absolute value to 2.642% (–2.050%), whereas positive (negative) IR premia increase to 1.039% (–1.151%). Zero exposure betas have zero risk premia. We find that, depending on the level of profitability, Size, book-to-market-ratio (B/M) and sales-to-stock price ratio (S/P) explain most of the variation in exposure betas and risk premia. Our results imply that investors view exposure betas and risk premia as important factors affecting portfolio returns

Genome Composition and Divergence of the Novel Coronavirus (2019-nCoV) Originating in China.

An in-depth annotation of the newly discovered coronavirus (2019-nCoV) genome has revealed differences between 2019-nCoV and severe acute respiratory syndrome (SARS) or SARS-like coronaviruses. A systematic comparison identified 380 amino acid substitutions between these coronaviruses, which may have caused functional and pathogenic divergence of 2019-nCoV

Flowing water enabled piezoelectric potential of flexible composite film for enhanced photocatalytic performance

Fast charge transfer and low recombination rate are two vital requirements to achieve high photocatalytic activity. In this work, we report the conversion of flowing water energy to piezoelectric potential on a new type of flexible composite film PVDF-NaBiTiO-BiOClBr (PV-N-B) containing PVDF-NaBiTiO (PV-N) substrate and BiOClBr, which significantly boosts the charge transfer of the photocatalytic composite film, resulting in improved photocatalytic capability by 2.33 times. The role of piezoelectric potential in photocatalysis process has been discussed in detail and the results reveal that higher potential output is more beneficial for photocatalytic performance enhancement. Moreover, the photocatalytic degradation intermediates of tetracycline (TC) over PV-N-B were detected by liquid chromatography-mass spectrometer and the possible photodegradation pathway of TC has been reasonably proposed. It is verified that superoxide radicals are the main active species for PV-N-B to degrade TC. The durability experiments demonstrate the good stability of flexible composite film PV-N-B. In a wider perspective, this work provides an efficient flexible composite film, with great capability in converting flowing water energy into piezoelectric potential and improving photocatalytic activity, to bring the environmental pollution under control

A CRISPR-Cas12a—Based platform for ultrasensitive, rapid, and highly specific detection of Mycoplasma pneumonia in clinical application

Mycoplasma pneumoniae (MP), which is responsible for a majority of community-acquired pneumonia (CAP) in children, has been largely underestimated. Here, we coupled multiple cross displacement amplification (MCDA) technique with CRISPR-Cas12a-based biosensing system to design a novel detection platform termed MP-MCDA-CRISPR assay for MP infection diagnosis and clinical application. The MP-MCDA-CRISPR assay amplified the CARDS gene of MP by MCDA method, followed by trans-cleavage of the reporter molecular upon the formation of CRISPR-Cas12a-gRNA-target DNA complex, which was confirmed by the release of fluorescent signals. A set of standard MCDA primers, an engineered CP1 primer, a quenched fluorescent ssDNA reporter, and a gRNA were designed targeting the CARDS gene of MP. The optimal temperature for MCDA pre-amplification is 64°C, and the time for CRISPR-Cas12a-gRNA biosensing process is 5 min. The limit of detection (LoD) of the MP-MCDA-CRISPR assay is 50 fg per reaction without any cross-reaction with other non-MP pathogens. The MP-MCDA-CRISPR assay accurately identified the 50 real time-PCR positive clinical samples and 78 negative ones. Taken together, the MP-MCDA-CRISPR assay designed here is a promising diagnostic tool for point-of care (POC) testing of MP infection

Epidemiology of birth defects based on a birth defects surveillance system in southwestern China and the associated risk factors

BackgroundBirth defects (BDs) are associated with many potential risk factors, and its causes are complex.ObjectivesThis study aimed to explore the epidemiological characteristics of BDs in Guangxi of China and the associated risk factors of BDs.MethodsBDs data of perinatal infants (PIs) were obtained from the Guangxi birth defects monitoring network between 2016 and 2020. Univariate Poisson regression was used to calculate the prevalence-rate ratios (PRR) to explore the changing trends of BDs prevalence by year and the correlation between the regarding of characteristics of BDs (including infant gender, maternal age, and quarter) and BDs. Clinical characteristics of PIs with BDs and general characteristics of their mothers were documented, and Spearman correlation analysis was used to explore the potential associated risk factors of BDs.ResultsBetween 2016 and 2020, 44,146 PIs with BDs were monitored, with an overall BDs prevalence of 121.71 (95% CI: 120.58–122.84) per 10,000 PIs, showing a significant increase trend (PRR = 1.116, 95% CI: 1.108–1.123), especially the prevalence of congenital heart defects (CHDs) that most significantly increased (PRR = 1.300, 95% CI: 1.283–1.318). The 10 most common BDs were CHDs, polydactyly, congenital talipes equinovarus, other malformation of external ear, syndactyly, hypospadias, cleft lip with cleft palate, cleft lip, hemoglobin Bart's hydrops fetalis syndrome (BHFS), and congenital atresia of the rectum and anus. BDs were positively correlated with pregnant women's age (R = 0.732, P < 0.01) and education level (R = 0.586, P < 0.05) and having pre-gestational diabetes mellitus (PGDM)/gestational diabetes mellitus (GDM) (R = 0.711, P < 0.01), while when the pregnant women had a family history of a dead fetus (R = −0.536, P < 0.05) and a birth of a fetus with BDs (R = −0.528, P < 0.05) were negatively correlated with BDs.ConclusionA significant increase in the prevalence of BDs was detected between 2016 and 2020 in Guangxi, especially the prevalence of CHDs that most significantly increased. Older maternal age, higher maternal education level, and having PGDM before pregnancy or GDM in early pregnancy were the risk factors for BDs

Liver Transcriptome Analysis of the Large Yellow Croaker (Larimichthys crocea) during Fasting by Using RNA-Seq.

The large yellow croaker (Larimichthys crocea) is an economically important fish species in Chinese mariculture industry. To understand the molecular basis underlying the response to fasting, Illumina HiSeqTM 2000 was used to analyze the liver transcriptome of fasting large yellow croakers. A total of 54,933,550 clean reads were obtained and assembled into 110,364 contigs. Annotation to the NCBI database identified a total of 38,728 unigenes, of which 19,654 were classified into Gene Ontology and 22,683 were found in Kyoto Encyclopedia of Genes and Genomes (KEGG). Comparative analysis of the expression profiles between fasting fish and normal-feeding fish identified a total of 7,623 differentially expressed genes (P < 0.05), including 2,500 upregulated genes and 5,123 downregulated genes. Dramatic differences were observed in the genes involved in metabolic pathways such as fat digestion and absorption, citrate cycle, and glycolysis/gluconeogenesis, and the similar results were also found in the transcriptome of skeletal muscle. Further qPCR analysis confirmed that the genes encoding the factors involved in those pathways significantly changed in terms of expression levels. The results of the present study provide insights into the molecular mechanisms underlying the metabolic response of the large yellow croaker to fasting as well as identified areas that require further investigation