Distinct laccase expression and activity profiles of Trametes versicolor facilitate degradation of benzo[a]pyrene.

A Trametes versicolor isolate from the Changbai Mountain showed promising activity in degrading benzo[a]pyrene (BaP), which is a high molecular weight (HMW) polycyclic aromatic hydrocarbon (PAH) compound. It was hypothesized that the T. versicolor isolate encode BaP-degrading enzymes, among which laccase is mostly sought after due to significant commercial potential. Genome of the T. versicolor isolate was sequenced and assembled, and seven laccase homologues were identified (TvLac1-7) as candidate genes potentially contributing to BaP degradation. In order to further identify the BaP responsive laccases, time-course transcriptomic and proteomic analyses were conducted in parallel on the T. versicolor isolate upon BaP treatment. Homologous laccases showed distinct expression patterns. Most strikingly, TvLac5 was rapidly induced in the secreted proteomes (secretomes), while TvLac2 was repressed. Recombinant laccase expression and biochemical characterization further showed corresponding enzymatic activity profiles, where TvLac5 was 21-fold more effective in BaP degradation compared to TvLac2. Moreover, TvLac5 also showed 3.6-fold higher BaP degrading activity compared to a commercial laccase product of T. versicolor origin. Therefore, TvLac5 was concluded to be a BaP-responsive enzyme from T. versicolor showing effective BaP degradation activity.

PHB production from food waste hydrolysates by Halomonas bluephagenesis Harboring PHB operon linked with an essential gene.

Food wastes can be hydrolyzed into soluble microbial substrates, contributing to sustainability. Halomonas spp.-based Next Generation Industrial Biotechnology (NGIB) allows open, unsterile fermentation, eliminating the need for sterilization to avoid the Maillard reaction that negatively affects cell growth. This is especially important for food waste hydrolysates, which have a high nutrient content but are unstable due to batch, sources, or storage conditions. These make them unsuitable for polyhydroxyalkanoate (PHA) production, which usually requires limitation on either nitrogen, phosphorous, or sulfur. In this study, H. bluephagenesis was constructed by overexpressing the PHA synthesis operon phaCABCn (cloned from Cupriavidus necator) controlled by the essential gene ompW (encoding outer membrane protein W) promoter and the constitutive porin promoter that are continuously expressed at high levels throughout the cell growth process, allowing poly(3-hydroxybutyrate) (PHB) production to proceed in nutrient-rich (also nitrogen-rich) food waste hydrolysates of various sources. The recombinant H. bluephagenesis termed WZY278 generated 22 g L-1 cell dry weight (CDW) containing 80 wt% PHB when cultured in food waste hydrolysates in shake flasks, and it was grown to 70 g L-1 CDW containing 80 wt% PHB in a 7-L bioreactor via fed-batch cultivation. Thus, unsterilizable food waste hydrolysates can become nutrient-rich substrates for PHB production by H. bluephagenesis able to be grown contamination-free under open conditions.

Traffic Crash Characteristics in Shenzhen, China from 2014 to 2016.

Road traffic crashes cause fatalities and injuries of both drivers/passengers in vehicles and pedestrians outside, thus challenge public health especially in big cities in developing countries like China. Previous efforts mainly focus on a specific crash type or causation to examine the crash characteristics in China while lacking the characteristics of various crash types, factors, and the interplay between them. This study investigated the crash characteristics in Shenzhen, one of the biggest four cities in China, based on the police-reported crashes from 2014 to 2016. The descriptive characteristics were reported in detail with respect to each of the crash attributes. Based on the recorded crash locations, the land-use pattern was obtained as one of the attributes for each crash. Then, the relationship between the attributes in motor-vehicle-involved crashes was examined using the Bayesian network analysis. We revealed the distinct crash characteristics observed between the examined levels of each attribute, as well the interplay between the attributes. This study provides an insight into the crash characteristics in Shenzhen, which would help understand the driving behavior of Chinese drivers, identify the traffic safety problems, guide the research focuses on advanced driver assistance systems (ADASs) and traffic management countermeasures in China.

Pelvic floor assessment using magnetic resonance imaging after vaginal delivery and elective caesarean delivery.

INTRODUCTION AND HYPOTHESIS: We aimed to compare quantitative static and dynamic magnetic resonance imaging (MRI) measurements of pelvic floor changes during postpartum recovery from 1 week to 6 months after different modes of delivery. METHODS: In this prospective study, 51 primiparous women (vaginal delivery group: 30 women; elective caesarean delivery group: 21 women) underwent static and dynamic MRI at 1 week, 6 weeks, 3 months, and 6 months postpartum to measure pelvic floor MRI values. Between-group differences in pelvic floor values at these time points were determined; subsequently, within-group comparisons according to time were performed. Analysis included independent samples t-tests and paired t-tests. RESULTS: The puborectal hiatus line (H line), muscular pelvic floor relaxation line (M line), bladder-pubococcygeal line (B-PCL), and uterus-pubococcygeal line (U-PCL) differed significantly between groups during the Valsalva manoeuvre at 1 week postpartum (p < 0.05). The H line, M line, and B-PCL values differed significantly between groups during the Valsalva manoeuvre at 6 weeks postpartum (p < 0.05). There were few significant between-group differences in pelvic floor values at 3 months and 6 months postpartum. In the vaginal delivery group, the differences in the H line and M line at 1 week, 6 weeks, and 3 months postpartum were significant (p < 0.001). In the elective caesarean delivery group, U-PCL differed significantly at 6 weeks compared to 1 week postpartum during the Valsalva manoeuvre (p < 0.05). CONCLUSIONS: Pelvic floor recovery primarily occurred during the early phase after delivery in both groups. Elective caesarean delivery had a non-significant protective effect on postpartum pelvic floor structure and function compared to vaginal delivery.

Association between Crash Attributes and Drivers' Crash Involvement: A Study Based on Police-Reported Crash Data.

Understanding the association between crash attributes and drivers' crash involvement in different types of crashes can help figure out the causation of crashes. The aim of this study was to examine the involvement in different types of crashes for drivers from different age groups, by using the police-reported crash data from 2014 to 2016 in Shenzhen, China. A synthetic minority oversampling technique (SMOTE) together with edited nearest neighbors (ENN) were used to solve the data imbalance problem caused by the lack of crash records of older drivers. Logistic regression was utilized to estimate the probability of a certain type of crashes, and odds ratios that were calculated based on the logistic regression results were used to quantify the association between crash attributes and drivers' crash involvement in different types of crashes. Results showed that drivers' involvement patterns in different crash types were affected by different factors, and the involvement patterns differed among the examined age groups. Knowledge generated from the present study could help improve the development of countermeasures for driving safety enhancement.

Influence of traffic congestion on driver behavior in post-congestion driving.

Traffic congestion is more likely to lead to aggressive driving behavior that is associated with increased crash risks. Previous studies mainly focus on driving behavior during congestion when studying congestion effects. However, the negative effects of congestion on driving behavior may also affect drivers' post-congestion driving. To fill this research gap, this study examined the influence of traffic congestion on driver behavior on the post-congestion roads (i.e., the roads travelled right after congestion). Twenty-five subjects participated in a driving simulation study. They were asked to complete two trials corresponding to post-congestion and non-congestion conditions, respectively. Driver behavior quantified by driving performance measures, eye movement measures, and electroencephalogram (EEG) measures was compared between the two conditions. Ten features were selected from the measures with statistical significance. The selected features were integrated to characterize drivers' response patterns using a hierarchical clustering method. The results showed that driver behavior in post-congestion situations became more aggressive, more focused in the forward area but less focused in the dashboard area, and was associated with lower power of the ß-band in the temporal brain region. The clustering results showed more aggressive and lack-of-aware response patterns while driving in post-congestion situations. This study revealed that traffic congestion negatively affected driver behavior on the post-congestion roads. Practical implications for driving safety education was discussed based on the findings from the present study.

Characterization of enterovirus 71 infection and associated outbreak of Hand, Foot, and Mouth Disease in Shawo of China in 2012.

Infection of enterovirus 71 (EV71) and associated hand, foot, and mouth disease (HFMD) are recognized as emerging public health issues worldwide. Hundreds of thousands of children are annually infected with EV71 and develop HFMD in China alone. Studies of EV71 infection are critical to the treatment and prevention of the associated HFMD outbreaks. In this report, we studied an outbreak of 105 HFMD cases in Shawo Township of China between September to October 2012. More than 90% of cases were children younger than 9 years old, with over 50% of cases aged 3-6 years old. Laboratory studies detected a high prevalence of EV71 and suggested EV71 as the most common enterovirus causing HFMD in Shawo. Sequencing analysis showed that the EV71 strains from Shawo belong to the C4 subgenotype, and are phylogenetically more related to those from the distant city of Nanchang than those from the nearby city of Wuhan with distinct variations. More girls were found to be associated with EV71 in Shawo whereas more boys were associated with EV71 in Wuhan and Nanchang. Our studies further the understanding of the molecular epidemiological features of HFMD and infection by enteroviruses in China.

Effect of over-expression of phasin gene from Aeromonas hydrophila on biosynthesis of copolyesters of 3-hydroxybutyrate and 3-hydroxyhexanoate.

The gene phaPAh, encoding the protein phasin that is associated with poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHHx) granule of Aeromonas hydrophila 4AK4, was cloned and characterized. Recombinant strains harboring additional copies of the phasin gene (phaPAh) and the polyhydroxyalkanoate (PHA) synthase gene (phaCAh) accumulated PHBHHx copolyesters consisting of 21 mol% 3-hydroxyhexanoate (3HHx) as compared to 14 mol% 3HHx produced by wild type strain. The molecular weight of PHBHHx produced by the above recombinants was lower than that obtained from the wild type strain grown under similar conditions. Over-expression of phaPAh led to the production of more PHA granules but with reduced sizes. SDS-PAGE showed that PhaPAh was the predominant protein present in the PHBHHx granules. The RT-PCR results suggested that phasin PhaPAh, regulated phaCAh gene at the transcription level. Gene PhaPWe from Wautersia eutropha (formerly Ralstonia eutropha; encoding a 20 kDa protein with low amino acid homology to the A. hydrophila 13 kDa protein) cloned into A. hydrophila 4AK4 exhibited similar effects on PHBHHx production and PHBHHx composition. These data suggest that the phasins could represent a protein family possessing similar functions but different structures.