3,852 research outputs found
Strengthen user authentication on mobile devices by using user’s touch dynamics pattern
Mobile devices, particularly the touch screen mobile devices, are increasingly used to store and access private and sensitive data or services, and this has led to an increased demand for more secure and usable security services, one of which is user authentication. Currently, mobile device authentication services mainly use a knowledge-based method, e.g. a PIN-based authentication method, and, in some cases, a fingerprint-based authentication method is also supported. The knowledge-based method is vulnerable to impersonation attacks, while the fingerprint-based method can be unreliable sometimes. To overcome these limitations and to make the authentication service more secure and reliable for touch screen mobile device users, we have investigated the use of touch dynamics biometrics as a mobile device authentication solution by designing, implementing and evaluating a touch dynamics authentication method. This paper describes the design, implementation, and evaluation of this method, the acquisition of raw touch dynamics data, the use of the raw data to obtain touch dynamics features, and the training of the features to build an authentication model for user identity verification. The evaluation results show that by integrating the touch dynamics authentication method into the PIN-based authentication method, the protection levels against impersonation attacks is greatly enhanced. For example, if a PIN is compromised, the success rate of an impersonation attempt is drastically reduced from 100% (if only a 4-digit PIN is used) to 9.9% (if both the PIN and the touch dynamics are used). © 2019, The Author(s)
Sensing Your Touch: Strengthen User Authentication via Touch Dynamic Biometrics
© 2019 IEEE. Mobile devices are increasingly used to store private and sensitive data, and this has led to an increased demand for more secure and usable authentication services. Currently, mobile device authentication services mainly use a knowledge-based method, e.g. a PIN-based authentication method, and, in some cases, a fingerprint-based authentication method is also supported. The knowledge-based method is vulnerable to impersonation attacks, while the fingerprint-based method can be unreliable sometimes. To make the authentication service more secure and reliable for mobile device users, this paper describes our efforts in investigating the benefits of integrating a touch dynamics authentication method into a PIN-based authentication method. It describes the design, implementation and evaluation of this method. Experimental results show that this approach can significantly reduce the success rate of impersonation attempts; in the case of a 4-digit PIN, the success rate is reduced from 100% (if only the PIN is used) to 9.9% (if both the PIN and the touch dynamics are used)
Small poly-L-lysines improve cationic lipid-mediated gene transfer in vascular cells in vitro and in vivo
The potential of two small poly-L-lysines ( sPLLs), low molecular weight sPLL ( LMW-L) containing 7 - 30 lysine residues and L18 with 18 lysine repeats, to enhance the efficiency of liposome-mediated gene transfer ( GT) with cationic lipid DOCSPER {[}1,3- dioleoyloxy- 2-( N-5-carbamoyl-spermine)-propane] in vascular smooth muscle cells ( SMCs) was investigated. Dynamic light scattering was used for determination of particle size. Confocal microscopy was applied for colocalization studies of sPLLs and plasmid DNA inside cells. GT was performed in proliferating and quiescent primary porcine SMCs in vitro and in vivo in porcine femoral arteries. At low ionic strength, sPLLs formed small complexes with DNA ( 50 100 nm). At high ionic strength, large complexes ( 11 mu m) were observed without any significant differences in particle size between lipoplexes ( DOCSPER/ DNA) and lipopolyplexes ( DOCSPER/ sPLL/ DNA). Both sPLLs were colocalized with DNA inside cells 24 h after transfection, protecting DNA against degradation. DOCSPER/ sPLL/ DNA formulations enhanced GT in vitro up to 5- fold, in a porcine model using local periadventitial application up to 1.5- fold. Both sPLLs significantly increased liposome- mediated GT. Poly-L-lysine L18 was superior to LMW-L since it enabled maximal GT at a 10-fold lower concentration. Thus, sPLLs may serve as enhancers for GT applications in SMCs in vitro and in vivo using local delivery. Copyright (c) 2007 S. Karger AG, Basel
Comparison of Artificial Neural Network and Logistic Regression Models for Predicting In-Hospital Mortality after Primary Liver Cancer Surgery
BACKGROUND: Since most published articles comparing the performance of artificial neural network (ANN) models and logistic regression (LR) models for predicting hepatocellular carcinoma (HCC) outcomes used only a single dataset, the essential issue of internal validity (reproducibility) of the models has not been addressed. The study purposes to validate the use of ANN model for predicting in-hospital mortality in HCC surgery patients in Taiwan and to compare the predictive accuracy of ANN with that of LR model. METHODOLOGY/PRINCIPAL FINDINGS: Patients who underwent a HCC surgery during the period from 1998 to 2009 were included in the study. This study retrospectively compared 1,000 pairs of LR and ANN models based on initial clinical data for 22,926 HCC surgery patients. For each pair of ANN and LR models, the area under the receiver operating characteristic (AUROC) curves, Hosmer-Lemeshow (H-L) statistics and accuracy rate were calculated and compared using paired T-tests. A global sensitivity analysis was also performed to assess the relative significance of input parameters in the system model and the relative importance of variables. Compared to the LR models, the ANN models had a better accuracy rate in 97.28% of cases, a better H-L statistic in 41.18% of cases, and a better AUROC curve in 84.67% of cases. Surgeon volume was the most influential (sensitive) parameter affecting in-hospital mortality followed by age and lengths of stay. CONCLUSIONS/SIGNIFICANCE: In comparison with the conventional LR model, the ANN model in the study was more accurate in predicting in-hospital mortality and had higher overall performance indices. Further studies of this model may consider the effect of a more detailed database that includes complications and clinical examination findings as well as more detailed outcome data
An Evidence-Based Medical Review on Promoting Gastrointestinal Function Recovery After Colorectal Cancer Surgery
Chun-Yu Zhao,1 Wan-Hong Shi,2 Zheng-Qi Wen,3 Yong-Mei Jin,4 Yun-Bo Shang,5 Lei Zheng,3 Juan Li,2 Xin-Min Chen2 1School of Nursing, Dali University, Dali, 671000, People’s Republic of China; 2Department of General Surgery, Third People’s Hospital of Yunnan Province, Kun Ming, 650000, People’s Republic of China; 3Department of Surgical Oncology, the First Affiliated Hospital of Kunming Medical University, Kun Ming, 650000, People’s Republic of China; 4Department of Nursing, Shanghai Seventh People’s Hospital, Shanghai, 200137, People’s Republic of China; 5Department of Emergency, Third People’s Hospital of Yunnan Province, Kun Ming, 650000, People’s Republic of ChinaCorrespondence: Yun-Bo Shang, Department of Emergency, Third People’s Hospital of Yunnan Province, No. 292 of Beijing Road, Guandu District, Kun Ming, 650000, People’s Republic of China, Tel +86-13708876606, Fax +8663196549, Email [email protected] Zheng-Qi Wen, Department of Surgical oncology, The First Affiliated Hospital of Kunming Medical University, Kun Ming, 650000, People’s Republic of China, Tel +86-13888079932, Email [email protected]: The objective of this study was to search for, evaluate, and summarize data related to a faster postoperative recovery in patients with colorectal cancer (CRC) based on literature from China as well as internationally. This will serve as an evidence-based foundation for the clinical implementation of enhanced postoperative recovery of gastrointestinal function in patients with CRC.Methods: Based on the hierarchical “ 6S” evidence model, we conducted a systematic search of computerized decision-support systems, guideline websites, as well as domestic and international databases for evidence, guidelines, expert consensus statements, clinical decision-making, best practices, evidence summaries, and systematic reviews of interventions focusing on accelerating gastrointestinal function rehabilitation after CRC surgery. The time limit for the search was from the date of creation of the database to January 2023. Two researchers evaluated the quality of the literature that was included, and we extracted data and summarized the evidence from those publications that fulfilled the quality criteria.Results: The review included a total of 21 publications, comprising 6 guidelines, 6 systematic reviews, 3 expert consensus statements, 4 randomized controlled trials, and 2 evidence summaries. We summarized 51 best evidence findings across five areas: organizational management, preoperative risk assessment, education, intraoperative monitoring, and postoperative management.Conclusion: There is a wide variety and wealth of information available on interventions to promote enhanced postoperative recovery of gastrointestinal function in patients with CRC. The use of evidence is discussed, keeping in mind the practical situation in China.Keywords: colorectal cancer, evidence-based nursing, evidence summary, gastrointestinal function recovery, postoperativ
The sudden change phenomenon of quantum discord
Even if the parameters determining a system's state are varied smoothly, the
behavior of quantum correlations alike to quantum discord, and of its classical
counterparts, can be very peculiar, with the appearance of non-analyticities in
its rate of change. Here we review this sudden change phenomenon (SCP)
discussing some important points related to it: Its uncovering,
interpretations, and experimental verifications, its use in the context of the
emergence of the pointer basis in a quantum measurement process, its appearance
and universality under Markovian and non-Markovian dynamics, its theoretical
and experimental investigation in some other physical scenarios, and the
related phenomenon of double sudden change of trace distance discord. Several
open questions are identified, and we envisage that in answering them we will
gain significant further insight about the relation between the SCP and the
symmetry-geometric aspects of the quantum state space.Comment: Lectures on General Quantum Correlations and their Applications, F.
F. Fanchini, D. O. Soares Pinto, and G. Adesso (Eds.), Springer (2017), pp
309-33
The Harris hip score: Do ceiling effects limit its usefulness in orthopedics?: A systematic review
The Harris hip score (HHS), a disease-specific health status scale that is frequently used to measure the outcome of total hip arthroplasty, has never been validated properly. A questionnaire is suitable only when all 5 psychometric properties are of sufficient quality. We questioned the usefulness of the HHS by investigating its content validity. We performed a systematic review based on a literature search in PubMed, Embase, and the Cochrane Library for descriptive studies published in 2007. 54 studies (59 patient groups) met our criteria and were included in the data analysis. To determine the content validity, we calculated the ceiling effect (percentage) for each separate study and we pooled data to measure the weighted mean. A subanalysis of indications for THA was performed to differentiate the populations for which the HHS would be suitable and for which it would not. A ceiling effect of 15% or less was considered to be acceptable. Over half the studies (31/59) revealed unacceptable ceiling effects. Pooled data across the studies included (n = 6,667 patients) suggested ceiling effects of 20% (95%CI: 18-22). Ceiling effects were greater (32%, 95%CI:12-52) in those patients undergoing hip resurfacing arthroplasty. Although the Harris hip score is widely used in arthroplasty research on outcomes, ceiling effects are common and these severely limit its validity in this field of researc
Ferritins: furnishing proteins with iron
Ferritins are a superfamily of iron oxidation, storage and mineralization proteins found throughout the animal, plant, and microbial kingdoms. The majority of ferritins consist of 24 subunits that individually fold into 4-α-helix bundles and assemble in a highly symmetric manner to form an approximately spherical protein coat around a central cavity into which an iron-containing mineral can be formed. Channels through the coat at inter-subunit contact points facilitate passage of iron ions to and from the central cavity, and intrasubunit catalytic sites, called ferroxidase centers, drive Fe2+ oxidation and O2 reduction. Though the different members of the superfamily share a common structure, there is often little amino acid sequence identity between them. Even where there is a high degree of sequence identity between two ferritins there can be major differences in how the proteins handle iron. In this review we describe some of the important structural features of ferritins and their mineralized iron cores and examine in detail how three selected ferritins oxidise Fe2+ in order to explore the mechanistic variations that exist amongst ferritins. We suggest that the mechanistic differences reflect differing evolutionary pressures on amino acid sequences, and that these differing pressures are a consequence of different primary functions for different ferritins
Image informatics strategies for deciphering neuronal network connectivity
Brain function relies on an intricate network of highly dynamic neuronal connections that rewires dramatically under the impulse of various external cues and pathological conditions. Among the neuronal structures that show morphologi- cal plasticity are neurites, synapses, dendritic spines and even nuclei. This structural remodelling is directly connected with functional changes such as intercellular com- munication and the associated calcium-bursting behaviour. In vitro cultured neu- ronal networks are valuable models for studying these morpho-functional changes. Owing to the automation and standardisation of both image acquisition and image analysis, it has become possible to extract statistically relevant readout from such networks. Here, we focus on the current state-of-the-art in image informatics that enables quantitative microscopic interrogation of neuronal networks. We describe the major correlates of neuronal connectivity and present workflows for analysing them. Finally, we provide an outlook on the challenges that remain to be addressed, and discuss how imaging algorithms can be extended beyond in vitro imaging studies
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