Initial Value Problems for the Second Order Mixed Monotone Type of Impulsive Differential Equations in Banach Spaces

AbstractIn this paper, we use the coupled fixed point theorem for mixed monotone condensing operators to obtain an existence and uniqueness theorem of solutions of initial value problems for the second order mixed monotone type of impulsive differential equations and its application

Marine data collection based on embedded system with wired and wireless transmission

A great interest of boat manufacturers is to improve their products by knowing how the boats are used after sale. In order to gather information about the condition of usages, a system needs to be developed in order to collect data from different marine electronics mounted on the boat. Through this thesis work, we developed such data collecting system for leisure boats which support CAN Bus the message-based protocol. The data collection system has been developed and installed on a Linux-based embedded system connected to the CAN Bus network through a gateway in our laboratory. Through the data collection system, all data generated from different marine electronics in the network can be captured, filtered, transmitted, displayed and then stored in the system. For data transmission and access, we have implemented three methods through wired or wireless networks, i.e., the fixed Internet, 3G/LTE cellular networks and Wi-Fi networks. Furthermore, the prototype implementation has been extensively tested in both lab and real-life environment

A New Method for Isolation of Interstitial Fluid from Human Solid Tumors Applied to Proteomic Analysis of Ovarian Carcinoma Tissue

Major efforts have been invested in the identification of cancer biomarkers in plasma, but the extraordinary dynamic range in protein composition, and the dilution of disease specific proteins make discovery in plasma challenging. Focus is shifting towards using proximal fluids for biomarker discovery, but methods to verify the isolated sample's origin are missing. We therefore aimed to develop a technique to search for potential candidate proteins in the proximal proteome, i.e. in the tumor interstitial fluid, since the biomarkers are likely to be excreted or derive from the tumor microenvironment. Since tumor interstitial fluid is not readily accessible, we applied a centrifugation method developed in experimental animals and asked whether interstitial fluid from human tissue could be isolated, using ovarian carcinoma as a model. Exposure of extirpated tissue to 106 g enabled tumor fluid isolation. The fluid was verified as interstitial by an isolated fluid:plasma ratio not significantly different from 1.0 for both creatinine and Na+, two substances predominantly present in interstitial fluid. The isolated fluid had a colloid osmotic pressure 79% of that in plasma, suggesting that there was some sieving of proteins at the capillary wall. Using a proteomic approach we detected 769 proteins in the isolated interstitial fluid, sixfold higher than in patient plasma. We conclude that the isolated fluid represents undiluted interstitial fluid and thus a subproteome with high concentration of locally secreted proteins that may be detected in plasma for diagnostic, therapeutic and prognostic monitoring by targeted methods

The Effect of Intra-Abdominal Hypertension Incorporating Severe Acute Pancreatitis in a Porcine Model

Introduction: Abdominal compartment syndrome (ACS) and intra abdominal hypertension(IAH) are common clinical findings in patients with severe acute pancreatitis(SAP). It is thought that an increased intra abdominal pressure(IAP) is associated with poor prognosis in SAP patients. But the detailed effect of IAH/ACS on different organ system is not clear. The aim of this study was to assess the effect of SAP combined with IAH on hemodynamics, systemic oxygenation, and organ damage in a 12 h lasting porcine model

A Concerted Kinase Interplay Identifies PPARγ as a Molecular Target of Ghrelin Signaling in Macrophages

The peroxisome proliferator-activator receptor PPARγ plays an essential role in vascular biology, modulating macrophage function and atherosclerosis progression. Recently, we have described the beneficial effect of combined activation of the ghrelin/GHS-R1a receptor and the scavenger receptor CD36 to induce macrophage cholesterol release through transcriptional activation of PPARγ. Although the interplay between CD36 and PPARγ in atherogenesis is well recognized, the contribution of the ghrelin receptor to regulate PPARγ remains unknown. Here, we demonstrate that ghrelin triggers PPARγ activation through a concerted signaling cascade involving Erk1/2 and Akt kinases, resulting in enhanced expression of downstream effectors LXRα and ABC sterol transporters in human macrophages. These effects were associated with enhanced PPARγ phosphorylation independently of the inhibitory conserved serine-84. Src tyrosine kinase Fyn was identified as being recruited to GHS-R1a in response to ghrelin, but failure of activated Fyn to enhance PPARγ Ser-84 specific phosphorylation relied on the concomitant recruitment of docking protein Dok-1, which prevented optimal activation of the Erk1/2 pathway. Also, substitution of Ser-84 preserved the ghrelin-induced PPARγ activity and responsiveness to Src inhibition, supporting a mechanism independent of Ser-84 in PPARγ response to ghrelin. Consistent with this, we found that ghrelin promoted the PI3-K/Akt pathway in a Gαq-dependent manner, resulting in Akt recruitment to PPARγ, enhanced PPARγ phosphorylation and activation independently of Ser-84, and increased expression of LXRα and ABCA1/G1. Collectively, these results illustrate a complex interplay involving Fyn/Dok-1/Erk and Gαq/PI3-K/Akt pathways to transduce in a concerted manner responsiveness of PPARγ to ghrelin in macrophages

Load distribution vector based attack strategies against power grid systems

Security issues in complex systems such as power grid, communication network, Internet, among others have attracted wide attention from academic, government and industry. In this paper, we investigate the vulnerabilities of power grid under a topology-based network model in the context of cascading failures caused by physical attacks against substations and transmission lines. In particular, we develop attack strategies from the attackers\u27 points of view, aiming to cause severe damage to the network efficiency, as a way to revealing the vulnerability of the system. We propose a new and useful metric, load distribution vector (LDV), to describe the properties of nodes and links. Based on the LDV, we develop a multi-node attack strategy and a multi-link attack strategy, which are proved to be stronger attacks than the traditional load-based attacks using the Western North American power grid data. For example, the removal of only three critical nodes in the grid can reduce more than 30% of the original network efficiency, and the removal of only three critical links can reduce the network efficiency by 23%. In the above cases, the traditional load-based schemes reduce the network efficiency by 23.57% and 18.35%, respectively. © 2012 IEEE

Revealing temporal features of attacks against smart grid

Protecting smart grid against malicious attacks is a major task for the power and energy community. While different initial failures could trigger cascading effects resulting in same or close final impact, the pattern of intermediate cascading process varies significantly. In this paper we propose an approach to analyze temporal features and predict critical intermediate stages to help prevent a massive cascading failure. Initial victims from most vulnerable set of nodes are tested in a topological cascading model under different fault tolerances, and the results reveal that they are usually followed by a dramatic increase of failed components at some critical point. By analyzing the processes of failure propagation, we identify important temporal features of cascading failure and predict critical moments to allow quick and proper response at an early stage. This work provides informative decision support for defense against large blackouts caused either by random contingencies or attack schemes. © 2013 IEEE

Revealing cascading failure vulnerability in power grids using risk-graph

Security issues related to power grid networks have attracted the attention of researchers in many fields. Recently, a new network model that combines complex network theories with power flow models was proposed. This model, referred to as the extended model, is suitable for investigating vulnerabilities in power grid networks. In this paper, we study cascading failures of power grids under the extended model. Particularly, we discover that attack strategies that select target nodes (TNs) based on load and degree do not yield the strongest attacks. Instead, we propose a novel metric, called the risk graph, and develop novel attack strategies that are much stronger than the load-based and degree-based attack strategies. The proposed approaches and the comparison approaches are tested on IEEE 57 and 118 bus systems and Polish transmission system. The results demonstrate that the proposed approaches can reveal the power grid vulnerability in terms of causing cascading failures more effectively than the comparison approaches

Equal rating opportunity analysis for detecting review manipulation

Online review plays an important role when people are making decisions to purchase a product or service. It is shown that sellers can benefit from boosting their product review or downgrading their competitors\u27 product review. Dishonest behavior on reviews can seriously affect both buyers and sellers. In this paper, we introduce a novel angle to detect dishonest reviews, called Equal Rating Opportunity (ERO) evaluation. The proposed ERO evaluation can detect embedded manipulation signals based on limited amount of data. Experiments based on real data are conducted. Four highly problematic products are successfully detected from 84 products