Intrusion Detection Systems for Community Wireless Mesh Networks

Wireless mesh networks are being increasingly used to provide affordable network connectivity to communities where wired deployment strategies are either not possible or are prohibitively expensive. Unfortunately, computer networks (including mesh networks) are frequently being exploited by increasingly profit-driven and insidious attackers, which can affect their utility for legitimate use. In response to this, a number of countermeasures have been developed, including intrusion detection systems that aim to detect anomalous behaviour caused by attacks. We present a set of socio-technical challenges associated with developing an intrusion detection system for a community wireless mesh network. The attack space on a mesh network is particularly large; we motivate the need for and describe the challenges of adopting an asset-driven approach to managing this space. Finally, we present an initial design of a modular architecture for intrusion detection, highlighting how it addresses the identified challenges

Chan-Vese Attention U-Net: An attention mechanism for robust segmentation

When studying the results of a segmentation algorithm using convolutional neural networks, one wonders about the reliability and consistency of the results. This leads to questioning the possibility of using such an algorithm in applications where there is little room for doubt. We propose in this paper a new attention gate based on the use of Chan-Vese energy minimization to control more precisely the segmentation masks given by a standard CNN architecture such as the U-Net model. This mechanism allows to obtain a constraint on the segmentation based on the resolution of a PDE. The study of the results allows us to observe the spatial information retained by the neural network on the region of interest and obtains competitive results on the binary segmentation. We illustrate the efficiency of this approach for medical image segmentation on a database of MRI brain images

Fast Marching Energy CNN

Leveraging geodesic distances and the geometrical information they convey is key for many data-oriented applications in imaging. Geodesic distance computation has been used for long for image segmentation using Image based metrics. We introduce a new method by generating isotropic Riemannian metrics adapted to a problem using CNN and give as illustrations an example of application. We then apply this idea to the segmentation of brain tumours as unit balls for the geodesic distance computed with the metric potential output by a CNN, thus imposing geometrical and topological constraints on the output mask. We show that geodesic distance modules work well in machine learning frameworks and can be used to achieve state-of-the-art performances while ensuring geometrical and/or topological properties

Characterization of radish mitochondrial atpA: influence of nuclear background on transcription of atpA -associated sequences and relationship with male sterility

We have previously shown that the mitochondrial gene atpA , encoding the α subunit of F 1 ATP synthase, is associated with DNA rearrangements and nuclear-specific transcript patterns in the male-sterile cytoplasm of Ogura radish. Here we present a detailed characterization of this gene from both the normal (fertile) and Ogura (male-sterile) cytoplasms of radish to determine if it is involved in Ogura cytoplasmic male sterility. The normal and Ogura radish atpA loci are virtually identical for 3.8 kb, including a 507 codon open reading frame whose product is approximately 92% identical to other plant ATPA polypeptides. Rearrangement breakpoints have been identified 613 bp 5′ and 1663 bp 3′ to the atpA coding region. The 5′ rearrangement breakpoint is located within a repeated sequence that has been associated with other rearrangement events in radish mitochondria. The previously identified transcript difference results from transcription originating upstream of this rearrangement site. Although the presence of this transcript is affected by nuclear background, analyses in several different sterile and fertile nuclear backgrounds indicate that the presence of this transcript is not strictly correlated with male sterility. In addition, normal levels of ATPA polypeptide are present in sterile plants containing the Ogura cytoplasm.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/43427/1/11103_2004_Article_BF00016123.pd

Global perspectives on the provision of diabetic retinopathy screening and treatment: Survey of health care professionals in 41 countries.

AIM: To assess the level of awareness and provision of screening and treatment for Diabetic Eye Disease (DED) comprising Diabetic Retinopathy (DR) and Diabetic Macular Edema (DME) among health care professionals. METHODS: The study was conducted in two phases. The first phase consisted of a qualitative study, based on semi-structured face-to-face and telephone interviews in 8 countries. The second phase used a quantitative approach utilising online surveys in 41 countries. The survey for health care professionals comprised of 43 questions covering provider information, practice characteristics, management of adults with diabetes and specific information from ophthalmologists on screening and treatments for DR. RESULTS: There were 2329 health care professionals who participated in the online survey. More than one third of diabetes specialists surveyed reported that they did not discuss eye care with their diabetes patients. Nearly two-thirds of all health care professionals surveyed reported that they had written information about diabetes for patients available in their practice. Only one in five (22%, n = 58) primary care providers reported they had material that contained sufficient information on eye complications, and 37% (n = 252) of ophthalmologists reported that they had sufficient information on eye complications. Sixty-five percent (n = 378) of ophthalmologists reported that most of their patients presented when visual problems had already occurred. Six percent (n = 36) stated that most of their patients presented when it was already too late for effective treatment. The most substantial barriers to eye health mentioned by health care professionals responding to the survey were: a patients' lack of knowledge and/or awareness about eye complications (43%), followed by lack of importance given to eye examinations by patients (33%), and the high cost of care (32%). Ophthalmologists also reported late screening (66%), and lack of patient education materials (55%) as obstacles for improving eye health outcomes. CONCLUSION: Health care professionals need to be appropriately supported and trained so they can provide adults with diabetes with information about the risks of DR, support them in reducing their risk, and advocate for the provision of affordable DR screening and treatment as required

The Scottish Bladder Cancer Quality Performance Indicators Influencing Outcomes, Prognosis, and Surveillance (Scot BC Quality OPS) Clinical Project

The aim of the Scot BC Quality OPS clinical project is to create a reliable prospective data set for evaluating real-world effectiveness and efficiency consequent to standardisation and monitoring of bladder cancer treatment (through the national Quality Performance Indicator programme) and streamlined surveillance in Scotland. Several work packages have been created, reflecting wide clinical and research collaboration

The Molecular Signature Underlying the Thymic Migration and Maturation of TCRαβ+CD4+CD8- Thymocytes

BACKGROUND: After positive selection, the newly generated single positive (SP) thymocytes migrate to the thymic medulla, where they undergo negative selection to eliminate autoreactive T cells and functional maturation to acquire immune competence and egress capability. METHODOLOGY/PRINCIPAL FINDINGS: To elucidate the genetic program underlying this process, we analyzed changes in gene expression in four subsets of mouse TCRαβ(+)CD4(+)CD8(-) thymocytes (SP1 to SP4) representative of sequential stages in a previously defined differentiation program. A genetic signature of the migration of thymocytes was thus revealed. CCR7 and PlexinD1 are believed to be important for the medullary positioning of SP thymocytes. Intriguingly, their expression remains at low levels in the newly generated thymocytes, suggesting that the cortex-medulla migration may not occur until the SP2 stage. SP2 and SP3 cells gradually up-regulate transcripts involved in T cell functions and the Foxo1-KLF2-S1P(1) axis, but a number of immune function-associated genes are not highly expressed until cells reach the SP4 stage. Consistent with their critical role in thymic emigration, the expression of S1P(1) and CD62L are much enhanced in SP4 cells. CONCLUSIONS: These results support at the molecular level that single positive thymocytes undergo a differentiation program and further demonstrate that SP4 is the stage at which thymocytes acquire the immunocompetence and the capability of emigration from the thymus

Maturation-Dependent Licensing of Naive T Cells for Rapid TNF Production

The peripheral naïve T cell pool is comprised of a heterogeneous population of cells at various stages of development, which is a process that begins in the thymus and is completed after a post-thymic maturation phase in the periphery. One hallmark of naïve T cells in secondary lymphoid organs is their unique ability to produce TNF rapidly after activation and prior to acquiring other effector functions. To determine how maturation influences the licensing of naïve T cells to produce TNF, we compared cytokine profiles of CD4+ and CD8+ single positive (SP) thymocytes, recent thymic emigrants (RTEs) and mature-naïve (MN) T cells during TCR activation. SP thymocytes exhibited a poor ability to produce TNF when compared to splenic T cells despite expressing similar TCR levels and possessing comparable activation kinetics (upregulation of CD25 and CD69). Provision of optimal antigen presenting cells from the spleen did not fully enable SP thymocytes to produce TNF, suggesting an intrinsic defect in their ability to produce TNF efficiently. Using a thymocyte adoptive transfer model, we demonstrate that the ability of T cells to produce TNF increases progressively with time in the periphery as a function of their maturation state. RTEs that were identified in NG-BAC transgenic mice by the expression of GFP showed a significantly enhanced ability to express TNF relative to SP thymocytes but not to the extent of fully MN T cells. Together, these findings suggest that TNF expression by naïve T cells is regulated via a gradual licensing process that requires functional maturation in peripheral lymphoid organs

Location, identity, amount and serial entry of chloroplast DNA sequences in crucifer mitochondrial DNAs

Southern blot hybridization techniques were used to examine the chloroplast DNA (cpDNA) sequences present in the mitochondrial DNAs (mtDNAs) of two Brassica species ( B. campestris and B. hirta ), two closely related species belonging to the same tribe as Brassica (Raphanus sativa, Crambe abyssinica) , and two more distantly related species of crucifers (Arabidopsis thaliana, Capsella bursa-pastoris) . The two Brassica species and R. sativa contain roughly equal amounts (12–14 kb) of cpDNA sequences integrated within their 208–242 kb mtDNAs. Furthermore, the 11 identified regions of transferred DNA, which include the 5′ end of the chloroplast psa A gene and the central segment of rpo B, have the same mtDNA locations in these three species. Crambe abyssinica mtDNA has the same complement of cpDNA sequences, plus an additional major region of cpDNA sequence similarity which includes the 16S rRNA gene. Therefore, except for the more recently arrived 16S rRNA gene, all of these cpDNA sequences appear to have entered the mitochondrial genome in the common ancestor of these three genera. The mitochondrial genomes of A. thaliana and Capsella bursa-pastoris contain significantly less cpDNA (5–7 kb) than the four other mtDNAs. However, certain cpDNA sequences, including the central portion of the rbc L gene and the 3′ end of the psa A gene, are shared by all six crucifer mtDNAs and appear to have been transferred in a common ancestor of the crucifer family over 30 million years ago. 1n conclusion, DNA has been transferred sequentially from the chloroplast to the mitochondrion during crucifer evolution and these cpDNA sequences can persist in the mitochondrial genome over long periods of evolutionary time.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/46968/1/294_2004_Article_BF00521276.pd