Impacts of bus overtaking policies on the capacity of bus stops

Long bus queues at busy stops plague bus systems in many cities. Since berths are laid-out in tandem, buses’ overtaking maneuvers are often prohibited or restricted, which can significantly reduce a bus stop’s discharge capacity. When overtaking is allowed, aggressive drivers may perform disruptive oblique insertion maneuvers that would undermine stop capacity and compromise safety. This paper develops parsimonious yet realistic simulation models to examine the impacts of different overtaking policies on bus-stop capacity. Key realistic features are considered, including the oblique insertions resulting from overtaking, impacts of a nearby traffic signal, and bus traffic characteristics (reaction and move-up times). Extensive numerical experiments unveil many new findings. Some are at odds with those reported by previous studies. In addition, we examine two strategies that can improve the stop capacity without incurring disruptive oblique insertions. Practical implications of our findings are discussed, especially on choosing the most productive overtaking policy and means to minimize the capacity lost to buses’ mutual blockage at stops. These implications have broad applications to various types of bus stops

Detection and Analysis of Lead, Cadmium and Arsenic Content in Common Vegetables

This study was carried out to detect content of heavy metals (Pb, Cd, and As) in vegetables, understand the current situation of heavy metal contamination in vegetables, and to provide scientific reference for further researches. It randomly selected 6 large vegetable markets and 6 supermarkets in Changsha City, selected 8 types of typical vegetables, and detected 96 samples. In accordance with maximum level of contaminants in foods in existing GB2762-2012 standard, Nemerow composite pollution index (Pt) and grading standards, it made evaluation: uncontaminated (Pt ≤ 1), mildly contaminated (1 ＜ Pt ≤2), moderately contaminated (2 ＜ Pt ≤3), and highly contaminated (Pt ＞ 3). Among 96 samples, range of content of Pb, Cd and As is (0.06-1.41), (0.06-1.26) and (0.00-0.91) mg /kg respectively; the over-limit rate of these metals exceeding the safety level is 78.13%, 45.83%, and 34.38% separately; the composite pollution index is in (0.90-6.05), the eggplant is 6.05 and hot pepper is 3.24; the content of Pb (F = 23.908, P = 0.001) and Cd ( F =64.908, P =0.000) are significantly different between 8 types of vegetables and there is no significant difference between the content of As ( F = 4. 634, P = 0.705 ＞ 0. 05) in 8 types of vegetables. Study shows that common vegetables in Changsha City has problem of excess Pb, Cd and As, and the Pb over-limit rate is the highest. The composite pollution index indicates that most heavy metal contamination of vegetables is mild and moderate contamination, melon, fruit and vegetable contamination is high contamination, and Cd is the major factor leading to contamination of melons, fruits and vegetables

Capacity approximations for near- and far-side bus stops in dedicated bus lanes

We develop analytical approximations for the bus-carrying capacities at near- and far-side stops with one or multiple curbside berths where buses operate in a dedicated bus lane. The approximations are derived using time-space diagrams of bus trajectories and probabilistic methods. They correctly account for the effects of key operating factors that were ignored or incorrectly addressed by previous methods. These factors include the signal timing and the distance between stop and signal. Comparison against computer simulation shows that our models furnish much more accurate estimates for near- and far-side stop capacities than previous methods in the literature. Numerical case studies are performed to examine how the stop capacity is affected by various operating factors. New findings and their practical implications are discussed

Correction to: Mechanisms of multiple neurotransmitters in the effects of Lycopene on brain injury induced by Hyperlipidemia

Abstract Following publication of the original article [1] it came to the attention of the Research Integrity Group that the following corrections were required

Mechanisms of multiple neurotransmitters in the effects of Lycopene on brain injury induced by Hyperlipidemia

Abstract Background Lycopene is a kind of carotenoid, with a strong capacity of antioxidation and regulating the bloodlipid. There has been some evidence that lycopene has protective effects on the central nervous system, but few studies have rigorously explored the role of neurotransmitters in it. Therefore, the present study was designed to investigate the effects of several neurotransmitters as lycopene exerts anti-injury effects induced by hyperlipidemia. Methods Eighty adult SD rats, half male and half female, were randomly divided into eight groups on the basis of serum total cholesterol (TC) levels and body weight. There was a control group containing rats fed a standard laboratory rodent chow diet (CD); a hypercholesterolemic diet (rat chow supplemented with 4% cholesterol, 1% cholic acid and 0.5% thiouracil – this is also called a CCT diet) group; a positive group (CCT + F) fed CCT, supplemented with 10 mg·kg·bw− 1·d− 1 fluvastatin sodium by gastric perfusion; and lycopene groups at five dose levels (CCT + LYCO) fed with CCT and supplied lycopene at doses of 5, 25, 45, 65, and 85 mg·kg·bw− 1·d− 1. The levels of TC, triglyceride (TG), low-density lipoprotein cholesterol (LDL-C), high density lipoprotein cholesterol (HDL-C), interleukin-1 (IL-1), tumor necrosis factor alpha (TNF-α), oxidized low density lipoprotein (ox-LDL), low-density lipoprotein receptor (LDLR), nerve growth factor (NGF), glutamic acid (Glu), Gamma aminobutyric acid (GABA), dopamine (DA), 5-hydroxytryptamine (5-HT), N-methyl-D-aspartate (NMDA1R), GABAA, 5-HT1, D1, and apoptosis-related proteins Caspase3, bax, and bcl-2 were measured after the experiment. Nissl staining was adopted to observe the morphological changes in neurons. Results At the end of the experiment, the levels of TC, TG, LDL-C, IL-1, TNF-α, and ox-LDL in the serum and brain as well as the content of Glu, DA, NMDA, and D1 in the brain of rats in the CCT group were higher than those in the control group (P<0.05); the levels of LDLR, NGF, GABA, 5-HT, GABAA, 5-HT1, and neuron quantities in the hippocampal CA1 and CA3 areas were lower than those in the control group (P<0.05). Compared to the CCT group, levels of TC, TG, LDL-C, IL-1, TNF-α, and ox-LDL in the serum and brain, as well as the content of Glu, DA and the expression of pro-apoptotic Caspase3 in the brain decreased in the rats with lycopene (25 mg to 85 mg) added to the diet (P<0.05); the levels of LDLR, NGF, GABA, 5-HT, GABAA, and 5-HT1 as well as the expression of anti-apoptotic bcl-2 and the neuron quantity in hippocampal CA1 and CA3 areas increased (P<0.05); further, the hippocampal cells were closely arranged. Lycopene dose was negatively correlated with the levels of TC, TG, and LDL-C in the serum and brain as well as levels of IL-1, TNF-α, ox-LDL, Glu/GABA, NMDA1R, and Caspase3 (P<0.05); it was positively correlated with the levels of LDLR, NGF, 5-HT, 5-HT1, GABAA, bcl-2, and the neuron quantity in hippocampal CA1 and CA3 areas (P<0.05). Conclusions Lycopene exerts anti-injury effects in the brain as-induced by hyperlipidemia. It can inhibit the elevation of serum TC, TG, and LDL-C in rats with hyperlipidemia while indirectly affecting the levels of TC, TG, and LDL-C in the brain, leading to a reduction in ox-LDL, IL-1, and TNF-α in the brain. This inhibits the release of Glu, which weakens nerve toxicity and downregulates pro-apoptotic Caspase3. Lycopene also plays an anti-injury role by promoting the release of the inhibitory neurotransmitter GABA and 5-HT, which enhances the protective effect, and by upregulating the anti-apoptotic bcl-2

Chromosome-scale genome of the human blood fluke Schistosoma mekongi and its implications for public health

Abstract Background Schistosoma mekongi is a human blood fluke causing schistosomiasis that threatens approximately 1.5 million humans in the world. Nonetheless, the limited available S. mekongi genomic resources have hindered understanding of its biology and parasite-host interactions for disease management and pathogen control. The aim of our study was to integrate multiple technologies to construct a high-quality chromosome-level assembly of the S. mekongi genome. Methods The reference genome for S. mekongi was generated through integrating Illumina, PacBio sequencing, 10 × Genomics linked-read sequencing, and high-throughput chromosome conformation capture (Hi-C) methods. In this study, we conducted de novo assembly, alignment, and gene prediction to assemble and annotate the genome. Comparative genomics allowed us to compare genomes across different species, shedding light on conserved regions and evolutionary relationships. Additionally, our transcriptomic analysis focused on genes associated with parasite-snail interactions in S. mekongi infection. We employed gene ontology (GO) enrichment analysis for functional annotation of these genes. Results In the present study, the S. mekongi genome was both assembled into 8 pseudochromosomes with a length of 404 Mb, with contig N50 and scaffold N50 lengths of 1168 kb and 46,759 kb, respectively. We detected that 43% of the genome consists of repeat sequences and predicted 9103 protein-coding genes. We also focused on proteases, particularly leishmanolysin-like metalloproteases (M8), which are crucial in the invasion of hosts by 12 flatworm species. Through phylogenetic analysis, it was discovered that the M8 gene exhibits lineage-specific amplification among the genus Schistosoma. Lineage-specific expansion of M8 was observed in blood flukes. Additionally, the results of the RNA-seq revealed that a mass of genes related to metabolic and biosynthetic processes were up-regulated, which might be beneficial for cercaria production. Conclusions This study delivers a high-quality, chromosome-scale reference genome of S. mekongi, enhancing our understanding of the divergence and evolution of Schistosoma. The molecular research conducted here also plays a pivotal role in drug discovery and vaccine development. Furthermore, our work greatly advances the understanding of host-parasite interactions, providing crucial insights for schistosomiasis intervention strategies. Graphical Abstrac