Optimized Design of Piled Embankment Using a Multi-Effect Coupling Model on a Coastal Highway

This study presents a multi-effect coupling model to optimize the design of a geosynthetic-reinforced pile-supported embankment (GRPSE) considering the coupling effects of soil arching, membranes, and pile–soil interaction on a coastal highway. The developed model could optimize the design of the GRPSE to fulfill the design and construction requirements at a relatively low project cost. This was achieved by adjusting the critical factors that govern the settlement of GRPSEs, such as pile spacing, tensile stiffness of geosynthetic reinforcement (GR), arrangement of piles, pile cap size, and cushion thickness. The model predictions were validated by a series of field tests using a range of geotechnical sensors. The results show that model predictions agreed with experimental measurements reasonably well. In addition, the results indicate that in comparison to a square arrangement of piles, a triangle net arrangement can decrease the differential settlement of pile soil. Furthermore, this study demonstrates that a change in the GR’s tensile stiffness has little impact on the settlement of GRPSEs. This study can help to improve the stability of roadbeds of coastal highways

Study on urban road speed limit for pedestrian and bicyclist traffic safety

In order to determine the influence of road speed limit on the risk of pedestrian and bicyclist casualties in urban public transportation in China, 371 pedestrian cases and 67 bicyclist cases with estimated vehicle impact speed and detailed injury information were selected from IVAC database which had been developed via an in-depth investigation of vehicle traffic accidents. The risk models of pedestrians and bicyclists in urban traffic environment were developed by using logistic regression method and the risks of pedestrian and bicyclist casualties were quantitatively analyzed. Four correction schemes of vehicle travel speed were defined and the number of pedestrian and bicyclist casualties was estimated again based on the risk models. The results show that the fatality risks at 70 km\ub7h-1 are about 3 times of that at 50 km\ub7h-1 and 13 times of that at 30 km\ub7h-1 for both pedestrians and bicyclists. The reduction of vehicle travel speed can obviously decrease the casualty risks of both pedestrians and bicyclists. These findings can provide a foundation for setting a more reasonable speed limit for urban roads. Meanwhile, they can also provide a reference for setting speed limit for rural roads

Functional proteomic discovery of Slr0110 as a central regulator of carbohydrate metabolism in Synechocystis sp. PCC 6803

The unicellular photosynthetic model-organism cyanobacterium Synechocystis sp. PCC6803 can grow photoautotrophically using CO(2) or heterotrophically using glucose as the sole carbon source. Several pathways are involved in carbon metabolism in Synechocystis, and the concerted regulation of these pathways by numerous known and unknown genes is critical for the survival and growth of the organism. Here, we report that a hypothetical protein encoded by the open reading frame slr0110 is necessary for heterotrophic growth of Synechocystis. The slr0110-deletion mutant is defective in glucose uptake, heterotrophic growth, and dark viability without detectable defects in autotrophic growth, whereas the level of photosystem II and the rate of oxygen evolution are increased in the mutant. Quantitative proteomic analysis revealed that several proteins in glycolysis and the oxidative pentose phosphate pathway are down-regulated, whereas proteins in photosystem II and phycobilisome are significantly up-regulated, in the mutant. Among the down-regulated proteins are glucose transporter, glucokinase, glucose-6-phosphate isomerase, and glucose-6-phosphate dehydrogenase and its assembly protein OpcA, suggesting that glycolysis, oxidative pentose phosphate, and glycogen synthesis pathways are significantly inhibited in the mutant, which was further confirmed by enzymatic assays and quantification of glycogen content. These findings establish Slr0110 as a novel central regulator of carbon metabolism in Synechocystis, and shed light on an intricate mechanism whereby photosynthesis and carbon metabolism are well concerted to survive the crisis when one or more pathways of the system are impaired

Image_1_Using mixed reality technique combines multimodal imaging signatures to adjuvant glioma photodynamic therapy.jpg

BackgroundPhotodynamic therapy (PDT) promotes significant tumor regression and extends the lifetime of patients. The actual operation of PDT often relies on the subjective judgment of experienced neurosurgeons. Patients can benefit more from precisely targeting PDT’s key operating zones.MethodsWe used magnetic resonance imaging scans and created 3D digital models of patient anatomy. Multiple images are aligned and merged in STL format. Neurosurgeons use HoloLens to import reconstructions and assist in PDT execution. Also, immunohistochemistry was used to explore the association of hyperperfusion sites in PDT of glioma with patient survival.ResultsWe constructed satisfactory 3D visualization of glioma models and accurately localized the hyperperfused areas of the tumor. Tumor tissue taken in these areas was rich in CD31, VEGFA and EGFR that were associated with poor prognosis in glioma patients. We report the first study using MR technology combined with PDT in the treatment of glioma. Based on this model, neurosurgeons can focus PDT on the hyperperfused area of the glioma. A direct benefit was expected for the patients in this treatment.ConclusionUsing the Mixed Reality technique combines multimodal imaging signatures to adjuvant glioma PDT can better exploit the vascular sealing effect of PDT on glioma.</p

Synthesis and biological characterization of a promising F-18 PET tracer for vesicular acetylcholine transporter

Nine fluorine-containing vesicular acetylcholine transporter (VAChT) inhibitors were synthesized and screened as potential PET tracers for imaging the VAChT. Compound 18a was one of the most promising carbonyl-containing benzovesamicol analogues; the minus enantiomer, (-)-18a displayed high potency (VAChT K(i) = 0.59 ± 0.06 nM) and high selectivity for VAChT versus receptors (> 10,000-fold). The radiosynthesis of (-)-[(18)F]18a was accomplished by a two-step procedure with 30 – 40% radiochemical yield. Preliminary biodistribution studies of (-)-[(18)F]18a in adult male Sprague–Dawley rats at 5, 30, 60 and 120 min post-injection (p.i.) were promising. The total brain uptake of (-)-[(18)F]18a was 0.684 ID%/g at 5 min p.i. and by 120 min p.i. slowly washed out to 0.409 %ID/g.; evaluation of regional brain uptake showed stable levels of ~0.800 %ID/g from 5 to 120 min p.i in the VAChT-enriched striatal tissue of rats, indicating the tracer had crossed the blood brain barrier and was retained in the striatum. Subsequent microPET brain imaging studies of (-)-[(18)F]18a in nonhuman primates (NHPs) showed high striatal accumulation in the NHP brain; the standardized uptake value (SUV) for striatum reached a maximum value of 5.1 at 15 min p.i. The time-activity curve for the target striatal region displayed a slow and gradual decreasing trend 15 min after injection, while clearance of the radioactivity from the cerebellar reference region was much more rapid. Pretreatment of NHPs with 0.25 mg/kg of the VAChT inhibitor (-)-vesamicol resulted in a ~90% decrease of striatal uptake compared to baseline studies. HPLC metabolite analysis of NHP plasma revealed that (-)-[(18)F]18a had a good in vivo stability. Together, these preliminary results suggest (-)-[(18)F]18a is a promising PET tracer candidate for imaging VAChT in the brain of living subjects