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Ensuring the safety operation of hazardous materials transport is critical. Many previous works have reported various method to promote safety, while in this work, we identified and explored an overlooked aspect that affect the safety -- the real-time road conditions. For example, the slippery wet road or road with holes cause accidents for hazardous materials transport. Therefore, we argue that it is necessary to monitor the road conditions in real-time, and computer vision algorithms can make it possible. The advances in computer vision techniques shed light on the realm of road condition assessment. We reviewed and compared existing algorithms in this work. We also listed the existing road condition datasets and provided insights into how to apply the monitoring process with the safety framework of hazardous material transport.

Computer simulation for pedestrian dynamics is at the same time an application area in which research has completed its cycle and an active and lively research context in which contributions from different disciplines still produce advancements on the state of the art. The study of effects of the presence of groups in the simulated population is object of growing interest in the community. While previous results have started to investigate the phenomenon, implying conflicting tendencies for pedestrians, mechanisms for the flexible management of cohesion among group members are still investigated both in continuous and discrete modelling efforts. The present effort is aimed at extending previous modelling efforts, preserving and improving the capability to generate overall plausible aggregated dynamics, while at the same time improving the precision in the microscopic group dynamics, with particular attention to the shape of dyads. The paper presents validated results based on empirical data from a controlled experiment, also discussing qualitative results in different common situations (bends and bottlenecks).

With more and more high-rise building springing into the cities, the movement of pedestrians on stairs is of great importance for the evacuation of these facilities; the topic of human performance on stairs has attracted a lot of researcher to study. However, there is still a lack of analysis of specific situations, such as mid-landing and merging behaviors. In this paper we employ a modified version of the Optimal Steps Model, modified by taking block-based floor field into consideration under open boundary conditions, to reproduce movement at mid-landing and study performance of occupants in stairwell. Movements on this kind of stairs are simulated and studied with the help of extended model: achieved results are in accord with previous research in respect of specific flow and fundamental diagram. Lane formations on stairs come into being before mid-landing area through simulations. Furthermore most people reach at the mid-landing by the outside stairs at higher density due to more space and less force from other agents, which is induced that outside of the stairs is good for evacuation. At last the model is implemented to study the effect of stairs geometry on merging behaviors, and it is found when corridor is connected to the landing opposite to the incoming stairs, this structure is biased in favor of occupants from stairs. The work in this paper is intended to better understand movement during stair evacuations and develop a technical foundation for codes and standards requirements as well as egress modeling techniques.

With 1 the development of society, more and more large-scale activities are conducted in the cities. The issue that how to avoid emergency in respect of human performance has attracted a lot of researchers. It is easy to find the counter-flow in large-scale activities. Bi-directional movement has attracted a lot of researchers to investigate. More attention is paid to the existence of lane formation in respect of experiments and simulations. However, few attentions are drawn to the definition of lane formation in counter-flow. In this paper, a method based on deep learning technique(DBSCAN) is proposed to define lane formation. Lane formation based on DBSCAN is used to gather the pedestrians in a group, and order parameters and time step are taken into consideration in order to obtain the number of lane formation explicitly. Then proposed method is compared with previous lane formation definition. All the lanes defined by previous method are quantified during movement process, which could reflect self-organization in time, while method introduced in this manuscript are measured after movement, which needs more data after event. The proposed method has the ability to calculate the number of the lanes. The work in this paper is intended to better understand movement during counter-flow in a corridor and develop a technical foundation for evacuation strategies in large-scale activities.

Human lymphatic vascular malformations (LMs), also known as cystic hygromas or lymphangioma, consist of multiple lymphatic endothelial cell-lined lymph-containing cysts. No animal model of this disease exists. To develop a mouse xenograft model of human LM, CD34NegCD31Pos LM lymphatic endothelial cells (LM-LEC) were isolated from surgical specimens and compared to foreskin CD34NegCD31Pos lymphatic endothelial cells (LECs). Cells were implanted into a mouse tissue engineering model for 1, 2 and 4 weeks. In vitro LM-LECs showed increased proliferation and survival under starvation conditions (P < 0.0005 at 48 h, two-way ANOVA), increased migration (P < 0.001, two-way ANOVA) and formed fewer (P = 0.029, independent samples t test), shorter tubes (P = 0.029, independent samples t test) than foreskin LECs. In vivo LM-LECs implanted into a Matrigel™-containing mouse chamber model assembled to develop vessels with dilated cystic lumens lined with flat endothelium, morphology similar to that of clinical LMs. Human foreskin LECs failed to survive implantation. In LM-LEC implanted chambers the percent volume of podoplaninPos vessels was 1.18 ± 2.24 % at 1 week, 6.34 ± 2.68 % at 2 weeks and increasing to 7.67 ± 3.60 % at 4 weeks. In conclusion, the significantly increased proliferation, migration, resistance to apoptosis and decreased tubulogenesis of LM-LECs observed in vitro is likely to account for their survival and assembly into stable LM-like structures when implanted into a mouse vascularised chamber model. This in vivo xenograft model will provide the basis of future studies of LM biology and testing of potential pharmacological interventions for patients with lymphatic malformations.

Background Dysfunctional lymphatic vessel formation has been implicated in a number of pathological conditions including cancer metastasis, lymphedema, and impaired wound healing. The vascular endothelial growth factor (VEGF) family is a major regulator of lymphatic endothelial cell (LEC) function and lymphangiogenesis. Indeed, dissemination of malignant cells into the regional lymph nodes, a common occurrence in many cancers, is stimulated by VEGF family members. This effect is generally considered to be mediated via VEGFR-2 and VEGFR-3. However, the role of specific receptors and their downstream signaling pathways is not well understood. Methods and Results Here we delineate the VEGF-C/VEGF receptor (VEGFR)-3 signaling pathway in LECs and show that VEGF-C induces activation of PI3K/Akt and MEK/Erk. Furthermore, activation of PI3K/Akt by VEGF-C/VEGFR-3 resulted in phosphorylation of P70S6K, eNOS, PLCc1, and Erk1/2. Importantly, a direct interaction between PI3K and VEGFR-3 in LECs was demonstrated both in vitro and in clinical cancer specimens. This interaction was strongly associated with the presence of lymph node metastases in primary small cell carcinoma of the lung in clinical specimens. Blocking PI3K activity abolished VEGF-C-stimulated LEC tube formation and migration. Conclusions Our findings demonstrate that specific VEGFR-3 signaling pathways are activated in LECs by VEGF-C. The importance of PI3K in VEGF-C/VEGFR-3-mediated lymphangiogenesis provides a potential therapeutic target for the inhibition of lymphatic metastasis.

Lymphatic vessels guide interstitial fluid, modulate immune responses by regulating leukocyte and antigen trafficking to lymph nodes, and in a cancer setting enable tumor cells to track to regional lymph nodes. The aim of the study was to determine whether primary murine lymphatic endothelial cells (mLECs) show conserved vascular endothelial growth factor (VEGF) signaling pathways with human LECs (hLECs). LECs were successfully isolated from murine dermis and prostate. Similar to hLECs, vascular endothelial growth factor (VEGF) family ligands activated MAPK and pAkt intracellular signaling pathways in mLECs. We describe a robust protocol for isolation of mLECs which, by harnessing the power of transgenic and knockout mouse models, will be a useful tool to study how LEC phenotype contributes to alterations in lymphatic vessel formation and function.

The adhesion molecule L1, which is extensively characterized in the nervous system, is also expressed in dendritic cells (DCs), but its function there has remained elusive. To address this issue, we ablated L1 expression in DCs of conditional knockout mice. L1-deficient DCs were impaired in adhesion to and transmigration through monolayers of either lymphatic or blood vessel endothelial cells, implicating L1 in transendothelial migration of DCs. In agreement with these findings, L1 was expressed in cutaneous DCs that migrated to draining lymph nodes, and its ablation reduced DC trafficking in vivo. Within the skin, L1 was found in Langerhans cells but not in dermal DCs, and L1 deficiency impaired Langerhans cell migration. Under inflammatory conditions, L1 also became expressed in vascular endothelium and enhanced transmigration of DCs, likely through L1 homophilic interactions. Our results implicate L1 in the regulation of DC trafficking and shed light on novel mechanisms underlying transendothelial migration of DCs. These observations might offer novel therapeutic perspectives for the treatment of certain immunological disorders.

Spin photocurrent and current-induced spin polarization were experimentally observed in a two-dimensional electron gas with Rashba spin splitting. The sign of the spin photocurrent was found to be strongly dependent on the polarization, the incidence angle and the wavelength of the laser. The relative ratio of the spin photocurrent (or Kerr rotation signal intensity) in different samples is in good agreement with the ratio of the Rashba coefficient determined by the SdH oscillation, which reveals the same mechanism behind the spin photocurrent and current-induced spin polarization. © 2007 American Institute of Physics.

The converse effects of spin photocurrent and current induced spin polarization are experimentally demonstrated in a two-dimensional electron gas system with Rashba spin splitting. Their consistency with the strength of the Rashba coupling as measured for the same system from beating of the Shubnikov-de Haas oscillations reveals a unified picture for the spin photocurrent, current-induced spin-polarization, and spin-orbit coupling. In addition, the observed spectral inversion of the spin photocurrent indicates a system with dominating structure inversion asymmetry.