22 research outputs found
A multi-biometric iris recognition system based on a deep learning approach
YesMultimodal biometric systems have been widely
applied in many real-world applications due to its ability to
deal with a number of significant limitations of unimodal
biometric systems, including sensitivity to noise, population
coverage, intra-class variability, non-universality, and
vulnerability to spoofing. In this paper, an efficient and
real-time multimodal biometric system is proposed based
on building deep learning representations for images of
both the right and left irises of a person, and fusing the
results obtained using a ranking-level fusion method. The
trained deep learning system proposed is called IrisConvNet
whose architecture is based on a combination of Convolutional
Neural Network (CNN) and Softmax classifier to
extract discriminative features from the input image without
any domain knowledge where the input image represents
the localized iris region and then classify it into one of N
classes. In this work, a discriminative CNN training scheme
based on a combination of back-propagation algorithm and
mini-batch AdaGrad optimization method is proposed for
weights updating and learning rate adaptation, respectively.
In addition, other training strategies (e.g., dropout method,
data augmentation) are also proposed in order to evaluate
different CNN architectures. The performance of the proposed
system is tested on three public datasets collected
under different conditions: SDUMLA-HMT, CASIA-Iris-
V3 Interval and IITD iris databases. The results obtained
from the proposed system outperform other state-of-the-art
of approaches (e.g., Wavelet transform, Scattering transform,
Local Binary Pattern and PCA) by achieving a Rank-1 identification rate of 100% on all the employed databases
and a recognition time less than one second per person
Identification of germline alterations of the mad homology 2 domain of SMAD3 and SMAD4 from the Ontario site of the breast cancer family registry (CFR)
Abstract
Introduction
A common feature of neoplastic cells is that mutations in SMADs can contribute to the loss of sensitivity to the anti-tumor effects of transforming growth factor-β (TGF-β). However, germline mutation analysis of SMAD3 and SMAD4, the principle substrates of the TGF-β signaling pathway, has not yet been conducted in breast cancer. Thus, it is currently unknown whether germline SMAD3 and SMAD4 mutations are involved in breast cancer predisposition.
Methods
We performed mutation analysis of the highly conserved mad-homology 2 (MH2) domains for both genes in genomic DNA from 408 non-BRCA1/BRCA2 breast cancer cases and 710 population controls recruited by the Ontario site of the breast cancer family registry (CFR) using denaturing high-performance liquid chromatography (DHPLC) and direct DNA sequencing. The results were interpreted in several ways. First, we adapted nucleotide diversity analysis to quantitatively assess whether the frequency of alterations differ between the two genes. Next, in silico tools were used to predict variants' effect on domain function and mRNA splicing. Finally, 37 cases or controls harboring alterations were tested for aberrant splicing using reverse-transcription polymerase chain reaction (PCR) and real-time PCR statistical comparison of germline expressions by non-parametric Mann-Whitney test of independent samples.
Results
We identified 27 variants including 2 novel SMAD4 coding variants c.1350G > A (p.Gln450Gln), and c.1701A > G (p.Ile525Val). There were no inactivating mutations even though c.1350G > A was predicted to affect exonic splicing enhancers. However, several additional findings were of note: 1) nucleotide diversity estimate for SMAD3 but not SMAD4 indicated that coding variants of the MH2 domain were more infrequent than expected; 2) in breast cancer cases SMAD3 was significantly over-expressed relative to controls (P A was associated with elevated germline expression (> 5-fold); 3) separate analysis using tissue expression data showed statistically significant over-expression of SMAD3 and SMAD4 in breast carcinomas.
Conclusions
This study shows that inactivating germline alterations in SMAD3 and SMAD4 are rare, suggesting a limited role in driving tumorigenesis. Nevertheless, aberrant germline expressions of SMAD3 and SMAD4 may be more common in breast cancer than previously suspected and offer novel insight into their roles in predisposition and/or progression of breast cancer
Citizen satisfaction with private security guards in the Netherlands: perceptions of an ambiguous occupation
The employment of private security guards has increased in many European countries in recent decades and the Netherlands is no exception. However, despite large increases in the growth of the private security industry, little is known about how the public perceives agents of private policing and their role in crime prevention and enhancing the public's sense of safety. In this paper we examine public perceptions of private security personnel. More specifically, we examine citizens' attitudes toward the nature of security guards' work, their relationship with public police, and their level of satisfaction with private police services. Findings suggest that, on the whole, Dutch citizens have mixed opinions about private security guards. Nonetheless, contrary to what is often assumed about the public image of private security, findings also suggest that respondents tend not to view the nature of security guards' work and their professionalism in purely negative terms. Contact with security guards was a key predictor of satisfaction with guard services. © The Author(s) 2010
Introduction: Governing Every Person, Place, and Thing — Critical Studies of Corporate Security
Direct elections and the local governance of crime in the United Kingdom: A view from the ground
Do We Trust Them? Public Opinion on Police Work in Plural Policing Environments in Central and Eastern Europe
Corporate security and the stratum of security management
Corporate security is a sector within the greater security domain, unique from contract private security, public policing and national security. Corporate security transverses both the private and public sectors and is embedded in small and large organisations. The Corporate Security Manager requires a set of skills and knowledge depending on their level of management as a line-, middle- or executive manager. At the line level, the Security Manager has high security-specific technical skills and knowledge; however, these are internal and isolated. As the Security Manager moves vertically in their organisation, skills become broader and less technical, encompassing risk management, business continuity, and physical, personnel and technical security. Security management may reach a glass ceiling at this level. To break into the executive requires generic skills such as an ability to understand business fundamentals as well as an external focus and an ability to shape the environment