bluuebunny/crossref_metadata_2025 huggingface dataset:
Contaminación del suelo en la zona minera de Rasgatá Bajo (Tausa). Modelo conceptual
Authors: Guerrero Useda María Eugenia , Pineda Acevedo Vanessa
Published: May 2016

Se desarrolló un modelo conceptual del riesgo de contaminación físico química del suelo en la vereda Rasgatá Bajo. Esta vereda del municipio de Tausa, en Cundinamarca, está en la zona limítrofe del declarado por la Corporación Autónoma Regional de Cundinamarca en 2009, Distrito Regional de Manejo Integrado de los Recursos Naturales Renovables Páramo Guargua y Laguna Verde. La vocación productiva local por tradición ha sido el cultivo de papa (Solanum tuberosum L) y la extracción y transformación de arcilla y carbón, actividades con graves impactos sobre el suelo, por lo que el objetivo del proyecto fue identificar y evaluar la condición de este recurso en territorios donde confluyen actividades de extracción y transformación de arcilla y carbón. Se siguió un enfoque metodológico mixto que combinó investigación documental, observaciones in situ y medición de características físico químicas para determinar las fuentes y tipos de contaminantes con riesgo de afectar el suelo aledaño a las faenas mineras y con impactos toxicológicos para las personas, la fauna y la flora. Los datos obtenidos aportarán al  rediseño y evaluación de los planes de manejo ambiental local.
El efecto día en los retornos del índice Colcap analizado con mapas autoorganizados
Authors: Ortiz Sandoval Juan David , Peña Cuéllar David René , Espitia Cuchango Helbert Eduardo
Published: May 2016

En este artículo se analiza el valor histórico del índice Colcap (el cual corresponde al índice de referencia del mercado accionario colombiano), utilizando un modelo de mapa autoorganizado de Kohonen (SOM). Esto se realiza para encontrar una correlación del día semanal con el retorno diario del índice. En el desarrollo se presentan los datos empleados como también la configuración del SOM para el entrenamiento. El mapa autoorganizado entrenado es visualizado por cada componente del vector de entrada para revelar gráficamente las predominancias existentes en el valor del retorno del índice Colcap respecto al día semanal.
General response observed in cyclically loaded cohesive soils
Authors: Nieto Leal Andres , Kaliakin Victor N.
Published: May 2016

The response of cohesive soils subjected to cyclic loading is affected by different factors; the most important are soil type, stress or consolidation history, and specific test conditions. To better understand the behavior of cohesive soils subjected to cyclic loading, beginning in early 1960’s, a rather substantial body of experimental work has been performed. This has involved different types of soils, tested at different values of overconsolidation ratio, and subjected to different cyclic loading histories. This paper compiles the most important findings of the aforementioned experimental work on cohesive soils. It summarizes the general behavioral trends observed for cyclically loaded cohesive soils. Besides, several key characteristics of cyclically loaded cohesive soils that any rational mathematical simulation must account for have been identified, thus offering the general trends that should be taken into account in the development of new constitutive models used in predicting the response of such soils.
Impact of Individual Decision-Making Styles on Marketing Information System Based Decision-Making: An Empirical Study of Saudi Arabia Manufacturing Firms
Authors: Mahmoud Ghazi A Alowaidi , Hu Wang
Published: May 2016

The present research was conducted on the subject on how various managerial traits have an impact on overall decision-making based on marketing information systems. The variables that were tested in order to verify if the relationship between the variables was important were rational decision-making, intuitive decision-making, dependent decision-making, avoidant decision-making, spontaneous decision-making, decision-making speed and finally decision quality. The comprehensive conclusion to the study was that the decision quality variable of information system use positively influences incremental marketing innovation and radical marketing innovation, exhibiting a distinct and significant connection.The research was conducted in Saudi Arabia manufacturing companies, allowing us to gain valuable insight and information on the present situation of the Saudi Arabia manufacturing industry and allowed us to acquire new knowledge on the marketing information systems in Saudi Arabia companies. In our hypothesized model, we investigated and analyzed the different personality traits on all managerial level of firms and organizations in Saudi Arabia and the direct influence on the aforementioned companies. The findings suggest that quality of decisions is a most significant factor of our model for marketing innovation, therefore managers must focus on improving this segment Saudi Arabia manufacturing companies. Decision making styles are partially relevant for decision speed and quality based on marketing information systems, however, they are not significantly relevant. Although IT has been implemented , the use of it has to be further promoted, with employees trained to achieve optimal organizational outcomes.
Impact Time Control Guidance Law Considering Seeker's Field-of-View Constraint Without Time-to-Go Information
Authors: Yang Zhe ,   School of Aerospace Engineering, Beijing Institute of Technology, Lin Defu , Zang Luyao
Published: May 2016

Accurate time-to-go estimation with large heading angle error is difficult for homing guidance laws, especially for the impact time control. Considering this, a new cooperative guidance law which requires no time-to-go estimation is investigated. First, the impact time control problem is transformed to the look angle command tracking problem. The look angle command guarantees that the range-to-go error converges to zero asymptotically. Then the proposed guidance law considering the seeker's field-of-view constraint is derived using sliding mode control to track the desired look angle signal. Numerical simulations are performed to verify the effectiveness of the proposed guidance law for one-to-one and many-to-one engagement scenarios.
Outcomes for Hip Arthroscopy According to Sex and Age
Authors: Frank Rachel M. , Lee Simon , Bush-Joseph Charles A. , Salata Michael J. , Mather Richard C. , Nho Shane J.
Published: May 2016

Background:

Factors such as age and sex are postulated to play a role in outcomes following arthroscopy for femoroacetabular impingement; however, to our knowledge, no data currently delineate outcomes on the basis of these factors. The purpose of this study was to compare clinical outcomes of patients undergoing hip arthroscopy for femoroacetabular impingement according to sex and age.

Methods:

One hundred and fifty patients undergoing hip arthroscopy for femoroacetabular impingement by a single fellowship-trained surgeon were prospectively analyzed, with 25 patients in each of the following groups: female patients younger than 30 years of age, female patients 30 to 45 years of age, female patients older than 45 years of age, male patients younger than 30 years of age, male patients 30 to 45 years of age, and male patients older than 45 years of age. The primary outcomes included the Hip Outcome Score Activities of Daily Living Subscale (HOS-ADL), Hip Outcome Score Sport-Specific Subscale (HOS-Sport), the modified Harris hip score (mHHS), and clinical improvement at the time of follow-up.

Results:

At a minimum 2-year follow-up, all groups demonstrated significant improvements in the HOS-ADL, the HOS-Sport, and the mHHS (p < 0.0001). Female patients older than 45 years of age scored significantly worse on the HOS-ADL, HOS-Sport, and mHHS compared with female patients younger than 30 years of age (p < 0.0001 for all) and female patients 30 to 45 years of age (p < 0.017 for all). Male patients older than 45 years of age scored significantly worse on all outcomes compared with male patients younger than 30 years of age (p ≤ 0.011 for all) and male patients 30 to 45 years of age (p ≤ 0.021 for all). Incorporating both sexes, patients older than 45 years of age scored significantly worse on all outcomes compared with patients younger than 30 years of age (p < 0.0001 for all) and patients 30 to 45 years of age (p ≤ 0.001 for all). Female patients older than 45 years of age had significantly reduced radiographic preoperative joint space width compared with the two other female groups and the male groups who were 45 years of age or younger (p < 0.05 for all).

Conclusions:

Although all patients had significant improvements in all outcomes following hip arthroscopy, patients older than 45 years of age performed worse than younger patients, with female patients older than 45 years of age demonstrating the lowest outcome scores. In the age group of 45 years or younger, female patients performed as well as male patients in terms of hip clinical outcome scores. Overall, care must be individualized to optimize outcomes following hip arthroscopy for femoroacetabular impingement.

Level of Evidence:

PrognosticLevel II. See Instructions for Authors for a complete description of levels of evidence.
Capital Femoral Growth Plate Extension Predicts Cam Morphology in a Longitudinal Radiographic Study
Authors: Morris William Z. , Weinberg Douglas S. , Gebhart Jeremy J. , Cooperman Daniel R. , Liu Raymond W.
Published: May 2016

Background:

Recent evidence has suggested that cam morphology may be related to alterations in the capital femoral growth plate during adolescence. The purpose of this study was to evaluate the relationship between capital femoral growth plate extension and cam morphology in a longitudinal radiographic study.

Methods:

We used a historical, longitudinal radiographic collection to identify 96 healthy adolescents (54 boys and 42 girls) with at least 5 consecutive annual radiographs of the left hip including closure of the capital femoral physis. We reviewed 554 anteroposterior radiographs of the left hip to measure the anteroposterior modification of the alpha angle of Nötzli and of the superior epiphyseal extension ratio (EER), measured as the ratio of extension of the capital femoral epiphysis down the femoral neck relative to the diameter of the femoral head. Measurements were made at 3 points in femoral head maturation corresponding to the Oxford bone age (OBA) femoral head stages 5, 6, and 7/8.

Results:

There was a mean increase in the anteroposterior alpha angle (10.7° ± 14.0°) and EER (0.12 ± 0.08) between OBA stages 5 and 7/8, corresponding to maturation and closure of the capital femoral physis. There was a positive correlation between the final anteroposterior alpha angle and both the final EER (r = 0.60) and the change in the EER (r = 0.58). A receiver operating characteristic curve generated to predict an anteroposterior alpha angle of ≥78° through the EER demonstrated an area under the curve of 0.93, indicating that an increasing EER had excellent diagnostic accuracy for predicting concurrent cam morphology.

Conclusions and Clinical Relevance:

Superior epiphyseal extension was directly and temporally associated with an increase in anteroposterior alpha angle and more cam-like morphology. This alteration in the capital femoral epiphysis occurred immediately before physeal closure (OBA stage 7/8). Given the association of epiphyseal extension with activities that increase shear forces across the physis, we proposed that epiphyseal extension may be an adaptive mechanism to stabilize the physis and prevent slipped capital femoral epiphysis.
Synthesis, Characterization and Antimicrobial Evaluation of Novel Mannich Bases Containing Pyrazole-5-One Phosphonates
Authors: Rani V. E. , Ravindranath L. K.
Published: May 2016

Background:

Newly synthesised compounds of phosphonates were prepared by condensation of diethylphosphate with imine which undergoes a reaction of mannich bases with pyrazole containing schiffs base. The base was prepared by condensation of aldehyde with primary amine. These newly synthesised derivatives were characterised by spectral analysis.

Objective:

Mannich bases are very important to synthesize wide variety of natural products and pharmaceuticals.

Method:

Thin Layer Chromatography was performed on aluminum sheet of silica gel 60F254, E-Merk, Germany using iodine as visualizing agent. IR Spectra were recorded as KBr pellets on Perkin-Elmer 1000 units, instruments. All 1H and 13C-NMR spectra were recorded on a Varian XL-300 spectrometer operating at 400MHz and 75 MHz. 31P-NMR spectra were recorded on a Varian XL-spectrometer operating at 161.89MHz. The compounds were dissolved in dimethylsulfoxide and Chemical shifts were referenced to Trimethylsilane (1H and 13C-NMR) and 85% phosphoric acid (31P-NMR).

Results:

Some of the novel synthetic compounds of Pyrazole Mannich base-Phosphonates showed great potential in field of medicinal chemistry and good biological activity.

Conclusion:

It can be concluded that this class of compounds certainly holds great potential for the discovery of novel classes of antimicrobial agents.
Association of Urinary Biomarkers of Inflammation, Injury, and Fibrosis with Renal Function Decline: The ACCORD Trial
Authors: Nadkarni Girish N. , Rao Veena , Ismail-Beigi Faramarz , Fonseca Vivian A. , Shah Sudhir V. , Simonson Michael S. , Cantley Lloyd , Devarajan Prasad , Parikh Chirag R. , Coca Steven G.
Published: May 2016

Background and objectives

Current measures for predicting renal functional decline in patients with type 2 diabetes with preserved renal function are unsatisfactory, and multiple markers assessing various biologic axes may improve prediction. We examined the association of four biomarker-to-creatinine ratio levels (monocyte chemotactic protein-1, IL-18, kidney injury molecule-1, and YKL-40) with renal outcome.

Design, setting, participants, & measurements

We used a nested case-control design in the Action to Control Cardiovascular Disease Trial by matching 190 participants with ≥40% sustained eGFR decline over the 5-year follow-up period to 190 participants with ≤10% eGFR decline in a 1:1 fashion on key characteristics (age within 5 years, sex, race, baseline albumin-to-creatinine ratio within 20 μg/mg, and baseline eGFR within 10 ml/min per 1.73 m2), with ≤10% decline. We used a Mesoscale Multiplex Platform and measured biomarkers in baseline and 24-month specimens, and we examined biomarker associations with outcome using conditional logistic regression.

Results

Baseline and 24-month levels of monocyte chemotactic protein-1-to-creatinine ratio levels were higher for cases versus controls. The highest quartile of baseline monocyte chemotactic protein-1-to-creatinine ratio had fivefold greater odds, and each log increment had 2.27-fold higher odds for outcome (odds ratio, 5.27; 95% confidence interval, 2.19 to 12.71 and odds ratio, 2.27; 95% confidence interval, 1.44 to 3.58, respectively). IL-18-to-creatinine ratio, kidney injury molecule-1-to-creatinine ratio, and YKL-40-to-creatinine ratio were not consistently associated with outcome. C statistic for traditional predictors of eGFR decline was 0.70, which improved significantly to 0.74 with monocyte chemotactic protein-1-to-creatinine ratio.

Conclusions

Urinary monocyte chemotactic protein-1-to-creatinine ratio concentrations were strongly associated with sustained renal decline in patients with type 2 diabetes with preserved renal function.
Association of mGFR of the Remaining Kidney Divided by Its Volume before Donation with Functional Gain in mGFR among Living Kidney Donors
Authors: Courbebaisse Marie , Gaillard François , Tissier Anne-Marie , Fournier Catherine , Le Nestour Alexis , Corréas Jean-Michel , Slimani-Thevenet Hind , Martinez Frank , Léon Carine , Eladari Dominique , Timsit Marc-Olivier , Otal Philippe , Hignette Chantal , Friedlander Gérard , Méjean Arnaud , Houillier Pascal , Kamar Nassim , Legendre Christophe
Published: May 2016

Background and objectives

The predictors of long–term renal function in living kidney donors are currently discussed. Our objectives were to describe the predictors of functional gain of the remaining kidney after kidney donation. We hypothesized that GFR of the remaining kidney divided by volume of this kidney (rk-GFR/vol) would reflect the density of functional nephrons and be inversely associated with functional gain of the remaining kidney.

Design, setting, participants, & measurements

We conducted a prospective monocentric study including 63 living donors (26 men; 50.3±11.8 years old) who had been evaluated for 51Cr-EDTA and measured GFR, split renal function by scintigraphy before donation (between 2004 and 2009), and measured GFR at 5.7±0.5 years after donation. For 52 donors, volume of the remaining kidney (measured and estimated with the ellipsoid formula using renal computed tomography scannography) was determined before donation. We tested our hypothesis in an external validation cohort of 39 living donors (13 men; 51.0±9.4 years old) from another single center during the same time period.

Results

For the main cohort, the mean measured GFR was 97.6±13.0 ml/min per 1.73 m2 before donation and 63.8±9.4 ml/min per 1.73 m2 at 5 years. Functional gain averaged 16.2±7.2 ml/min per 1.73 m2 (+35.3%±16.7%). Multivariate analysis showed that age, body mass index, and rk-GFR/vol at donation were negatively correlated with functional gain and had strong predictive power of the 5-year functional gain (adjusted 5-year functional gain for age: −0.4 [95% confidence interval (95% CI), −0.5 to −0.1]; body mass index: −0.3 [95% CI, −0.6 to −0.1]; rk-GFR/vol: −55.1 [95% CI, −92.3 to −17.9]). We tested this model in the external validation cohort (adjusted 5-year functional gain for age: −0.1 [95% CI, −0.5 to 0.3]; body mass index: −0.9 [95% CI, −1.8 to −0.1]; rk-GFR/vol: −97.6 [95% CI, −137.5 to −57.6]) and confirmed that rk-GFR/vol was inversely associated with 5-year functional gain.

Conclusions

For given age and body mass index, the long–term functional gain of the remaining kidney is inversely associated with the new variable rk-GFR/vol at donation.
Innovation sociale et innovation radicale sont-elles contradictoires ?
Authors: Levillain Kevin , Agogué Marine , Berthet Elsa T.
Published: May 2016

Rejetant l’idée selon laquelle les entrepreneurs sociaux sont intrinsèquement innovants, cet article explore en quoi la formulation de la mission sociale peut être un levier pour l’innovation radicale. Par l’étude longitudinale d’une PME spécialisée dans le traitement de la malnutrition, il montre l’enjeu pour cette entreprise de renouveler régulièrement sa mission de façon à impliquer les partenaires pertinents et stimuler l’exploration de voies conceptuelles nouvelles. Formuler une mission commune et générative semble être une condition pour l’innovation sociale radicale.
Influencer l’attention des décideurs
Authors: Mayer Julie C.
Published: May 2016

Dans un environnement complexe et surchargé d’information, gérer l’attention des décideurs constitue un défi pour les entreprises. Cet article étudie l’« issue-selling », c’est-à-dire la façon dont un acteur peut influencer l’attention décisionnelle en s’appuyant sur différents canaux. L’analyse des pratiques desrisk managers, en tant que coordinateurs de la gestion des risques, met en avant quatre postures d’issue-selling(pédagogue, superviseur, challenger, impulseur). Ces résultats affinent le concept d’issue-sellinget éclairent sur les rôles durisk manager.
La capacité d’absorption, un processus d’imitation de produits
Authors: Bourkha Bilal , Demil Benoît
Published: May 2016

Les entreprises confrontées aux innovations produits de leurs concurrents peuvent les imiter en développant une capacité d’absorption. En étudiant 57 imitations sur le marché des cartes bancaires, les auteurs montrent que cette capacité est le résultat délibéré d’une coordination entre différents services, que cette capacité évolue et routinise le processus de décision pour imiter, et que les connaissances sur les marchés connexes permettent de construire une capacité d’absorption potentielle alors que les actifs complémentaires influencent la capacité d’absorption réalisée.
The Anthropology of Literature in France
Authors: Fournier Laurent Sebastian , Privat Jean-Marie
Published: May 2016

In this article we present the ongoing theoretical discussions concerning
the relations between anthropology and literature in France.
We recall the historical relationship of a part of French anthropology
and the world of literature. We then try to show how the anthropology
of literature began by using the model of the anthropology of
art, mainly concentrating on literary works as individual creations
specific to the style or the cosmology of a given writer. We explore a
new perspective on the analysis of the social and symbolic meanings
of literary worlds, putting the emphasis on what is called ‘ethnocriticism’
in France. In order to understand better the influence of literature
and literary motives on contemporary cultural practices, and
to grasp the relation of literary works with the outside world and with
everyday life, we propose to build up a comparative approach of literary
works and rituals. Through different novels or other literary
works, we address possible developments of contemporary anthropologies
of literature in France.
Alessandro Testa (2014), Il carnevale dell’uomo-animale
Authors: Dietz Angelika
Published: May 2016

Alessandro Testa (2014), Il carnevale dell’uomo-animale: Le dimensioni storiche e socio-culturali di una festa appenninica (Napoli: Loffredo), 610 pp., Pb: €34.50, ISBN: 978-8-875-64675-2.
Improved Synthesis of Cytidine Diphosphate Choline (CDP-Choline) Via Selective Phosphorylation
Authors: Xia Ran , Sun Li-Ping , Chen Lei-Shan
Published: May 2016

An improved, three-step synthesis of cytidine diphosphate choline (CDP-choline) from cytidine was achieved in 68% overall yield. Selective phosphorylation of cytidine was accomplished by the use of morpholinophosphodichloridate to give cytidine-5′-phosphomorpholide, which was condensed with choline phosphate chloride in the presence of a catalytic amount of H2SO4 to give CDP-choline. The intermediates and products could be efficiently purified by recrystallisation, thus avoiding the use of chromatography at all stages. The reaction could be scaled up to 200 g in 64% overall yield, making this route attractive for industrial application.
Apples and Experts: Evolving Notions of Sustainable Agriculture
Authors: Ivey Linda L.
Published: May 2016

Current advocates of sustainable agriculture in the US posit that our food industry needs to recover from the deliberate missteps of the pioneers of chemical dependency and market-driven cultivation techniques that ushered in an age of industrial agriculture at the turn of the 20th century. A careful look at early 20th century agriculture in California, the theoretical ground zero of environmentally abusive cultivation techniques, reveals that this food industry history is more complex than it seems. Using the Central Coast of California as a case study, this article argues that a nexus of ambitious growers and a growing state agricultural bureaucracy worked to create a “brand name” and teach cultivation approaches that would buoy their local industry with increased production and expanded markets. But these same actors also embraced these changes with all due caution, keeping the long-term health of the industry and the community in mind. Whereas traditionally this juncture in California agricultural history is described as the moment where farmers sold out their traditional stewardship of the land for higher profits and chose non-sustainable agricultural practices, many growers actively pursued sustainable agriculture, at least as understood by them. In navigating market demands and technological changes, they made choices based on both economic grounds, and a modified agrarian ethic, shaped by concerns for environmental and social stability similar to the modern sustainability movement. Using examples ranging from state-sponsored erosion programs to local immigration policy, this article reveals a community that consciously made economic choices to keep up with larger competitors, but also monitored the impact of monoculture on their land and balanced an agrarian ideal with an increasingly ethnically diverse populace and a burgeoning class division. Their concern for social, economic and environmental stability reveal that there were more than market-driven missteps behind the emergence of our current system.
Scheduler vulnerabilities and coordinated attacks in cloud computing
Authors: Zhou Fangfei , Goel Manish , Desnoyers Peter , Sundaram Ravi
Published: May 2016

In hardware virtualization a hypervisor provides multiple Virtual Machines (VMs) on a single physical system, each executing a separate operating system instance. The hypervisor schedules execution of these VMs much as the scheduler in an operating system does, balancing factors such as fairness and I/O performance. As in an operating system, the scheduler may be vulnerable to malicious behavior on the part of users seeking to deny service to others or maximize their own resource usage.

Recently, publically available cloud computing services such as Amazon EC2 have used virtualization to provide customers with virtual machines running on the provider's hardware, typically charging by wall clock time rather than resources consumed. Under this business model, manipulation of the scheduler may allow theft of service at the expense of other customers, rather than merely re-allocating resources within the same administrative domain.

We describe a flaw in the Xen scheduler allowing virtual machines to consume almost all CPU time, in preference to other users, and demonstrate kernel-based and user-space versions of the attack. We show results demonstrating the vulnerability in the lab, consuming as much as 98% of CPU time regardless of fair share, as well as on Amazon EC2, where Xen modifications protect other users but still allow theft of service (following the responsible disclosure model, we have reported this vulnerability to Amazon; they have since implemented a fix that we have tested and verified). We provide a novel analysis of the necessary conditions for such attacks, and describe scheduler modifications to eliminate the vulnerability. We present experimental results demonstrating the effectiveness of these defenses while imposing negligible overhead.

Also, cloud providers such as Amazon's EC2 do not explicitly reveal the mapping of virtual machines to physical hosts [in: ACM CCS, 2009]. Our attack itself provides a mechanism for detecting the co-placement of VMs, which in conjunction with appropriate algorithms can be utilized to reveal this mapping. Other cloud computing attacks may use this mapping algorithm to detect the placement of victims.
EsPRESSO: Efficient privacy-preserving evaluation of sample set similarity
Authors: Blundo Carlo , De Cristofaro Emiliano , Gasti Paolo
Published: May 2016

Electronic information is increasingly often shared among entities without complete mutual trust. To address related security and privacy issues, a few cryptographic techniques have emerged that support privacy-preserving information sharing and retrieval. One interesting open problem in this context involves two parties that need to assess the similarity of their datasets, but are reluctant to disclose their actual content. This paper presents an efficient and provably-secure construction supporting the privacy-preserving evaluation of sample set similarity, where similarity is measured as the Jaccard index. We present two protocols: the first securely computes the (Jaccard) similarity of two sets, and the second approximates it, using MinHash techniques, with lower complexities. We show that our novel protocols are attractive in many compelling applications, including document/multimedia similarity, biometric authentication and genetic tests. In the process, we demonstrate that our constructions are appreciably more efficient than prior work.
Web search query privacy: Evaluating query obfuscation and anonymizing networks
Authors: Peddinti Sai Teja , Saxena Nitesh
Published: May 2016

Web Search is one of the most rapidly growing applications on the internet today. However, the current practice followed by most search engines – of logging and analyzing users' queries – raises serious privacy concerns. In this paper, we concentrate on two existing solutions which are relatively easy to deploy – namely Query Obfuscation and Anonymizing Networks. In query obfuscation, a client-side software attempts to mask real user queries via injection of certain noisy queries. Anonymizing networks route the user queries through a series of relay servers, hiding the actual query source from the search engine. A fundamental problem with these solutions, however, is that user queries are still obviously revealed to the search engine, although they are “mixed” among queries generated either by a machine or by other users. We focus on TrackMeNot (TMN), a popular query obfuscation tool, and the Tor anonymizing network, and try to analyse whether these solutions can actually preserve users' privacy in practice against an adversarial search engine. We demonstrate that a search engine, equipped with only a short-term history of a user's search queries, can break the privacy guarantees of TMN and Tor by only utilizing off-the-shelf machine learning techniques.
Towards user-oriented RBAC model
Authors: Lu Haibing , Hong Yuan , Yang Yanjiang , Duan Lian , Badar Nazia
Published: May 2016

Role mining is to define a role set to implement the role-based access control (RBAC) system and regarded as one of the most important and costliest implementation phases. While various role mining models have been proposed, we find that user experience/perception – one ultimate goal for any information system – is surprisingly ignored by the existing works. One advantage of RBAC is to support multiple role assignments and allow a user to activate the necessary role to perform the tasks at each session. However, frequent role activating and deactivating can be a tendinous thing from the user perspective. A user-friendly RBAC system is expected to assign few roles to every user. So in this paper we propose to incorporate to the role mining process a user-role assignment constraint that mandates the maximum number of roles each user can have. Under this rationale, we formulate user-oriented role mining as the user role mining problem, where all users have the same maximal role assignments, the personalized role mining problem, where users can have different maximal role assignments, and the approximate versions of the two problems, which tolerate a certain amount of deviation from the complete reconstruction. The extra constraint on the maximal role assignments poses a great challenge to role mining, which in general is already a hard problem. We examine some typical existing role mining methods to see their applicability to our problems. In light of their insufficiency, we present a new algorithm, which is based on a novel dynamic candidate role generation strategy, tailored to our problems. Experiments on benchmark data sets demonstrate the effectiveness of our proposed algorithm.
Model checking security properties of control flow graphs
Authors: Besson Frédéric , Jensen Thomas , Le Métayer Daniel , Thorn Tommy
Published: May 2016

A fundamental problem in software-based security is whether local security checks inserted into the code are sufficient to implement a global security property. This article introduces a formalism based on a linear-time temporal logic for specifying global security properties pertaining to the control flow of the program, and illustrates its expressive power with a number of existing properties. We define a minimalistic, security-dedicated program model that only contains procedure call and run-time security checks and propose an automatic method for verifying that an implementation using local security checks satisfies a global security property. We then show how to instantiate the framework to the security architecture of Java 2 based on stack inspection and privileged method calls.
Cardinality-based inference control in data cubes
Authors: Wang Lingyu , Wijesekera Duminda , Jajodia Sushil
Published: May 2016

This paper addresses the inference problem in on-line analytical processing (OLAP) systems. The inference problem occurs when the exact values of sensitive attributes can be determined through answers to OLAP queries. Most existing inference control methods are computationally expensive for OLAP systems, because they ignore the special structures of OLAP queries. By exploiting such structures, we derive cardinality-based sufficient conditions for safe OLAP data cubes. Specifically, data cubes are safe from inferences if their core cuboids are dense enough, in the sense that the number of known values is under a tight bound. We then apply the sufficient conditions on the basis of a three-tier inference control model. The model introduces an aggregation tier between data and queries. The aggregation tier represents a collection of safe data cubes that are pre-computed over a partition of the data using the proposed sufficient conditions. The aggregation tier is then used to provide users with inference-free queries. Our approach mitigates the performance penalty of inference control, because partitioning the data yields smaller input to inference control algorithms, pre-computing the aggregation tier reduces on-line delay, and using cardinality-based conditions guarantees linear-time complexity.
A unified model for unconditionally secure key distribution
Authors: Cimato Stelvio , Cresti Antonella , D'Arco Paolo
Published: May 2016

A key distribution scheme is a method by means of which a trusted party distributes pieces of information among a set of users in such a way that each group of them can compute a common key for secure communication. In this paper we present a model for unconditionally secure key distribution schemes, i.e., schemes whose security is independent of the power of the adversary. We prove lower bounds on the amount of information the trusted party has to generate and each user has to keep secret in such schemes, and we show that some previous unconditionally secure models for key distribution fall in our model. As a consequence, the lower bounds given in the literature for these models can be seen as corollaries of our results. Hence, the main contribution of the paper consists in pointing out a sort of common structure underlying some apparently different key distribution techniques.
Effective worm detection for various scan techniques
Authors: Xia Jianhong , Vangala Sarma , Wu Jiang , Gao Lixin , Kwiat Kevin
Published: May 2016

In recent years, the threats and damages caused by active worms have become more and more serious. In order to reduce the loss caused by fast-spreading active worms, an effective detection mechanism to quickly detect worms is desired. In this paper, we first explore various scan strategies used by worms on finding vulnerable hosts. We show that targeted worms spread much faster than random scan worms. We then present a generic worm detection architecture to monitor malicious worm activities. We propose and evaluate our detection mechanism called Victim Number Based Algorithm. We show that our detection algorithm is effective and able to detect worm events before 2% of vulnerable hosts are infected for most scenarios. Furthermore, in order to reduce false alarms, we propose an integrated approach using multiple parameters as indicators to detect worm events. The results suggest that our integrated approach can differentiate worm attacks from DDoS attacks and benign scans.
Prevention of information attacks by run-time detection of self-replication in computer codes
Authors: Skormin V. , Volynkin A. , Summerville D. , Moronski J.
Published: May 2016

This paper describes a novel approach for preventative protection from both known and previously unknown malicious software. It does not rely on screening the code for signatures of known viruses, but instead it detects attempts by the executable code in question to self-replicate during run time. Self-replication is the common feature of most malicious codes, allowing them to maximize their impact. This approach is an extension of the earlier developed method for detecting previously unknown viruses in script based computer codes. The paper presents a software tool implementing this technique for behavior-based run-time detection and suspension of self-replicating functionality in executable codes for Microsoft Windows operating systems.
Parity-based inference control for multi-dimensional range sum queries
Authors: Wang Lingyu , Li Yingjiu , Jajodia Sushil , Wijesekera Duminda
Published: May 2016

This paper studies the inference control of multi-dimensional range (MDR) sum queries. We show that existing inference control methods are usually inefficient for MDR queries. We then consider parity-based inference control that restricts users to queries involving an even number of sensitive values. Such a restriction renders inferences significantly more difficult, because an even number is closed under addition and subtraction, whereas inferences target at one value. However, more sophisticated inferences are still possible with only even MDR queries. We show that the collection of all even MDR queries causes inferences if and only if a special collection of sum-two queries (that is, the summation of exactly two values) does so. The result leads to an inference control method with an improved computational complexity [Formula: see text] (over the previous result of [Formula: see text]) for m MDR queries over n values. We show that no odd MDR queries can be answered without causing inferences. We show how to check non-MDR queries for inferences in linear time. We also show how to find large inference-free subsets of even MDR queries when they do cause inferences.
Folklore, practice and theory of robust combiners
Authors: Herzberg Amir
Published: May 2016

Cryptographic schemes are often designed as a combination of multiple component cryptographic modules. Such a combiner design is robust for a (security) specification if it meets the specification, provided that a sufficient subset of the components meet their specifications. A folklore combiner for encryption is cascade, i.e. [Formula: see text]. We show that cascade is a robust combiner for cryptosystems, under three important indistinguishability specifications: chosen plaintext attack (IND-CPA), non-adaptive chosen ciphertext attack (IND-CCA1), and replayable chosen ciphertext attack (IND-rCCA). We also show that cascade is not robust for the important specifications adaptive CCA (IND-CCA2) and generalized CCA (IND-gCCA). The IND-rCCA and IND-gCCA specifications are closely related, and this is an interesting difference between them. All specifications are defined within.

We also analyze few other basic and folklore combiners. In particular, we show that the following are robust combiners: the parallel combiner [Formula: see text] for one-way functions, the XOR-input combiner [Formula: see text] for cryptosystems, and the copy combiner [Formula: see text] for integrity tasks such as Message Authentication Codes (MAC) and signature schemes. Cascade is also robust for the hiding property of commitment schemes, and the copy combiner is robust for the binding property, but neither is a robust combiner for both properties.

We present (new) robust combiners for commitment schemes; these new combiners can be viewed as a composition of the cascade and the copy combiners. Our combiners are simple, efficient and practical.
Automatic verification of correspondences for security protocols
Authors: Blanchet Bruno
Published: May 2016

We present a new technique for verifying correspondences in security protocols. In particular, correspondences can be used to formalize authentication. Our technique is fully automatic, it can handle an unbounded number of sessions of the protocol, and it is efficient in practice. It significantly extends a previous technique for the verification of secrecy. The protocol is represented in an extension of the pi calculus with fairly arbitrary cryptographic primitives. This protocol representation includes the specification of the correspondence to be verified, but no other annotation. This representation is then translated into an abstract representation by Horn clauses, which is used to prove the desired correspondence. Our technique has been proved correct and implemented. We have tested it on various protocols from the literature. The experimental results show that these protocols can be verified by our technique in less than 1 s.
Adjoining classified and unclassified information by abstract interpretation
Authors: Giacobazzi Roberto , Mastroeni Isabella
Published: May 2016

Completeness in abstract interpretation models the ideal situation where no loss of precision is introduced in computations by approximating concrete data by their abstractions. If we interpret the abstraction as the ability of an attacker to distinguish, i.e., observe, properties of public computations, and the computation as the concrete denotational semantics of the program, then the lack of precision, encoded in abstract interpretation as a lack of completeness, corresponds precisely to the leakage of information corresponding to a violated security policy. This correspondence allows us to inherit, in the field of language-based security, the whole theory and methodology for making abstract domains complete. In particular, we prove that an adjoint relation exists between the power of the attacker and the amount of the information released – the more the attacker can observe, the less information can be kept private. This characterisation is achieved by interpreting, in the security context, the standard adjoint transformations making an abstract domain complete by refining and simplifying abstractions.
Automatically deriving information-theoretic bounds for adaptive side-channel attacks
Authors: Köpf Boris , Basin David
Published: May 2016

We present a model of adaptive attacks which we combine with information-theoretic metrics to quantify the information revealed to an adaptive adversary. This enables us to express an adversary's remaining uncertainty about a secret as a function of the number of interactions with the system under attack. We present algorithms and approximation methods for computing this function. The main application area for our approach is the analysis of side-channels in cryptographic algorithms and we give examples of how it can be used to characterize the vulnerability of hardware implementations to timing and power attacks. We also show the generality of our approach by using it to quantify the information leaked by a security protocol.
Exploiting predictability in click-based graphical passwords
Authors: van Oorschot P.C. , Thorpe Julie
Published: May 2016

We provide an in-depth study of the security of click-based graphical password schemes like PassPoints (Weidenbeck et al., 2005), by exploring popular points (hot-spots), and examining strategies to predict and exploit them in guessing attacks. We report on both short- and long-term user studies: one lab-controlled, involving 43 users and 17 diverse images, the other a field test of 223 user accounts. We provide empirical evidence that hot-spots do exist for many images, some more so than others. We explore the use of “human-computation” (in this context, harvesting click-points from a small set of users) to predict these hot-spots. We generate two “human-seeded” attacks based on this method: one based on a first-order Markov model, another based on an independent probability model. Within 100 guesses, our first-order Markov model-based attack finds 4% of passwords in one image's data set, and 10% of passwords in a second image's data set. Our independent model-based attack finds 20% within 233 guesses in one image's data set and 36% within 231 guesses in a second image's data set. These are all for a system whose full password space has cardinality 243. We evaluate our first-order Markov model-based attack with cross-validation of the field study data, which finds an average of 7–10% of user passwords within 3 guesses. We also begin to explore some click-order pattern attacks, which we found improve on our independent model-based attacks. Our results suggest that these graphical password schemes (with parameters as originally proposed) are vulnerable to offline and online attacks, even on systems that implement conservative lock-out policies.
Authorization enforcement in distributed query evaluation
Authors: De Capitani di Vimercati Sabrina , Foresti Sara , Jajodia Sushil , Paraboschi Stefano , Samarati Pierangela
Published: May 2016

We present a simple, yet powerful, approach for the specification and enforcement of authorizations regulating data release among data holders collaborating in a distributed computation, to ensure that query processing discloses only data whose release has been explicitly authorized. Data disclosure is captured by means of profiles, associated with each data computation, that describe the information carried by a base or a derived (i.e., computed by a query) relation. We present an algorithm that, given a query plan, determines whether it can be safely executed and produces a safe execution strategy for it. For each operation in a safe query plan, the algorithm determines the server(s) responsible for the execution, based on the entailed information flows, considering different strategies for the execution of joins. Finally, we discuss the architecture of a distributed database system based on the proposed model, illustrating possible design choices and their impact.
Towards cost-sensitive assessment of intrusion response selection
Authors: Stakhanova Natalia , Strasburg Chris , Basu Samik , Wong Johnny S.
Published: May 2016

In recent years, cost-sensitive intrusion response has gained significant interest mainly due to its emphasis on the balance between potential damage incurred by the intrusion and cost of the response. However, one of the challenges in applying this approach is defining consistent and adaptable measurements of these cost factors on the basis of requirements and policy of the system being protected against intrusions.

In this paper we present a framework for the cost-sensitive selection of intrusion response. Specifically, we introduce a set of measurements that characterize potential costs associated with the intrusion handling process and propose evaluation method of intrusion response with respect to the risk of potential intrusion damage, effectiveness of response action and response cost for a system. We provide an implementation of the proposed solution as a plugin tool for Snort IDS and demonstrate its advantages on DARPA data set and real network traffic.
Secure outsourced computation of iris matching
Authors: Blanton Marina , Aliasgari Mehrdad
Published: May 2016

Today biometric data propagate more heavily into our lives. With more ubiquitous use of such data, computations over biometrics become more prevalent as well. While it is well understood that privacy of biometric data must be protected, often computations over biometric data involve untrusted participants or servers, let it be a cross check between different agencies who are not permitted to share the data or a researcher testing a new biometric matching algorithm on a large scale that forces the computation to be placed on a grid. Unarguably, it would be desirable to secure computation over sensitive biometric data in such environments. Currently, no secure techniques for outsourcing biometric comparisons or searching are readily available, and this work makes the first step at designing solutions for secure outsourcing iris identification to one or more untrusted servers. We develop new solutions for the single-server (i.e., non-interactive) and multiple-server settings that use significantly different techniques. Furthermore, we carry out extensive experimentation on a database of iris codes to both validate the findings and achieve efficiency improvements.