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Increasing interest is developing towards soil-based agriculture as a long-term bioregenerative life support during space and planetary explorations. Contrary to hydroponics and aeroponics, soil-based cropping would offer an effective approach to sustain food and oxygen production, decompose organic wastes, sequester carbon dioxide, and filter water. However, the hydraulics and biogeochemical functioning of soil systems exposed to gravities lower than the Earth’s are still unknown. Since gravity is crucial in driving water flow, hypogravity will affect nutrient and oxygen transport in the liquid and gaseous phases, and could lead to suffocation of microorganisms and roots, and emissions of toxic gases. A highly mechanistic model coupling soil hydraulics and nutrient biogeochemistry previously tested on soils on Earth (g¼9.806 m s � 2 ) is used to highlight the effects of gravity on the functioning of cropping units on Mars (0.38 g), the Moon (0.16 g), and in the international space station (ISS, nearly 0 g). For each scenario, we have compared the net leaching of water, the leaching of NH3 ,N H 4 + ,N O 2 � and NO3 � solutes, the emissions of NH3 ,C O 2 ,N 2O, NO and N2 gases, the concentrations profiles of O2 ,C O 2 and dissolved organic carbon (DOC) in soil, the pH, and the dynamics of various microbial functional groups within the root zone against the same control variables in the soil under terrestrial gravity. The response of the soil ecodynamics was relatively linear; gravitational accelerations lower than the Earth’s resulted in 90–100% lower water leaching rates, 95–100% lower nutrient leaching rates, and lower emissions of NH3 and NO gases (80–95% and 30–40%, respectively). Lower N loss through leaching resulted in 60–100% higher concentration of the microbial biomass, but did not alter the vertical stratification of the microbial functional groups with respect to the stratification on Earth. However, the higher biomass concentration produced higher emissions of N2O, N2, and CO2 gases (80%, 200% and 40%, respectively).

The latest advances in bioregenerative strategies for long-term life support in extraterrestrial outposts such as on Mars have indicated soil-based cropping as an effective approach for waste decomposition, carbon sequestration, oxygen production, and water biofiltration as compared to hydroponics and aeroponics cropping. However, it is still unknown if cropping using soil systems could be sustainable in a Martian greenhouse under a gravity of 0.38g. The most challenging aspects are linked to the gravity-induced soil water flow; because water is crucial in driving nutrient and oxygen transport in both liquid and gaseous phases, a gravitational acceleration lower than g = 9.806 m s−2 could lead to suffocation of microorganisms and roots, with concomitant emissions of toxic gases. The effect of Martian gravity on soil processes was investigated using a highly mechanistic model previously tested for terrestrial crops that couples soil hydraulics and nutrient biogeochemistry. Net leaching of NO 3 - solute, gaseous fluxes of NH3, CO2, N2O, NO and N2, depth concentrations of O2, CO2 and dissolved organic carbon (DOC), and pH in the root zone were calculated for a bioregenerative cropping unit under gravitational acceleration of Earth and for its homologous on Mars, but under 0.38g. The two cropping units were treated with the same fertilizer type and rate, and with the same irrigation regime, but under different initial soil moisture content. Martian gravity reduced water and solute leaching by about 90% compared to Earth. This higher water holding capacity in soil under Martian gravity led to moisture content and nutrient concentrations that favoured the metabolism of various microbial functional groups, whose density increased by 5–10% on Mars as compared to Earth. Denitrification rates became substantially more important than on Earth and ultimately resulted in 60%, 200% and 1200% higher emissions of NO, N2O and N2 gases, respectively. Similarly, O2 and DOC were consumed more rapidly in the Martian soil and resulted in about 10% increase in CO2 emissions. More generally, Martian cropping would require 90% less water for irrigation than on Earth, being therefore favourable for water recycling treatment; in addition, a substantially lower nutrient supply from external sources such as fertilizers would not compromise nutrient delivery to soil microorganisms, but would reduce the large N gas emissions observed in this study.

We present a mathematical treatment of the kinetic equations that describe isotopologue and isotopomer speciation and fractionation during enzyme-catalyzed biochemical reactions. These equations, presented here with the name GEBIK (general equations for biochemical isotope kinetics) and GEBIF (general equations for biochemical isotope fractionation), take into account microbial biomass and enzyme dynamics, reaction stoichiometry, isotope substitution number, and isotope location within each isotopologue and isotopomer. In addition to solving the complete GEBIK and GEBIF, we also present and discuss two approximations to the full solutions under the assumption of biomass-free and enzyme steady-state, and under the quasi-steady-state assumption as applied to the complexation rate. The complete and approximate approaches are applied to observations of biological denitrification in soils. Our analysis highlights that the full GEBIK and GEBIF provide a more accurate description of concentrations and isotopic compositions of substrates and products throughout the reaction than do the approximate forms. We demonstrate that the isotopic effects of a biochemical reaction depend, in the most general case, on substrate and complex concentrations and, therefore, the fractionation factor is a function of time. We also demonstrate that inverse isotopic effects can occur for values of the fractionation factor smaller than 1, and that reactions that do not discriminate isotopes do not necessarily imply a fractionation factor equal to 1.

The 4q interstitial and terminal deletions have beenreported in more than 100 literature cases in associa-tion with variable clinical features (Strehle and Bantock,2003). The most frequent ones involve the breakpoints4q12q21.1, 4q31 and 4q33, while only in few reportsthere are more distal or interstitial deletions (Egger-mann

In this paper we focus on the aggregation of IDS alerts, an important component of the alert fusion process. We exploit fuzzy measures and fuzzy sets to design simple and robust alert aggregation algorithms. Exploiting fuzzy sets, we are able to robustly state whether or not two alerts are ''close in time'', dealing with noisy and delayed detections. A performance metric for the evaluation of fusion systems is also proposed. Finally, we evaluate the fusion method with alert streams from anomaly-based IDS.

Summary We describe the development and testing of a mechanistic model (BFLOC) to predict the average size of sediment aggregates in nutrient-rich aqueous ecosystems. The original capability of BFLOC is to couple turbulence-induced flocculation of suspended minerals and micro-organisms with the nutrient-related dynamics of aggregate-attached micro-organisms. The model, calibrated and validated against the average floc size recorded at two stations in the Belgian North Sea [Fettweis, M., Francken, F., Pison V., Ven den Eynde, D., 2006. Suspended particulate matter dynamics and aggregate sizes in a high turbidity area. Marine Geology 235, 63–74], closely captured site conditions and significantly clarified interpretation of field measurements. Modeling results indicated that an accurate prediction of time-varying floc sizes was possible only by taking into account the organic fraction of the suspended particle matter and the micro-organism colonization of the floc micro-environment. BFLOC showed that the floc excess density strongly correlated with the floc biomass volume, while the settling velocity strongly correlated with the floc mineral volume. We noticed that the settling velocity was poorly correlated with the total floc volume (and floc size), suggesting a revision of current methods that assess suspended matter deposition uniquely on the basis of the floc size. Additionally, various hypotheses tested with BFLOC suggested that the effect of aggregate-attached biomass on aggregation and breakup rates was very small when it was accounted for with a first-order description. More generally, the sediment and biomass parameters found here were nearly site independent suggesting that the mechanistic approach of BFLOC was relatively robust.

Insertional translocations (IT) are rare structural rearrangements. Offspring of IT balanced carriers are at high risk to have either pure partial trisomy or monosomy for the inserted segment as manifested by "pure" phenotypes. We describe an IT between chromosomes 3 and 13 segregating in a three-generation pedigree. Short tandem repeat (STR) segregation analysis and array-comparative genomic hybridization were used to define the IT as a 25.1 Mb segment spanning 13q21.2-q31.1. The phenotype of pure monosomy included deafness, duodenal stenosis, developmental and growth delay, vertebral anomalies, and facial dysmorphisms; the trisomy was manifested by only minor dysmorphisms. As the AUNA1 deafness locus on 13q14-21 overlaps the IT in the PCDH9 (protocadherin-9) gene region, PCDH9 was investigated as a candidate gene for deafness in both families. Genotyping of STRs and single nucleotide polymorphisms defined the AUNA1 breakpoint as 35 kb 5' to PCDH9, with a 2.4 Mb area of overlap with the IT. DNA sequencing of coding regions in the AUNA1 family and in the retained homologue chromosome in the monosomic patient revealed no mutations. We conclude that AUNA1 deafness does not share a common etiology with deafness associated with monosomy 13q21.2-q31.3; deafness may result from monosomy of PCHD9 or another gene in the IT, as has been demonstrated in contiguous gene deletion syndromes. Precise characterization of the breakpoints of the translocated region is useful to identify which genes may be contributing to the phenotype, either through haploinsufficiency or extra dosage effects, in order to define genotype-phenotype correlations.

Objective Pericentric inversion carriers are predisposed to produce unbalanced gametes that result in conceptuses having either a partial trisomy for one distal segment and a partial monosomy for the other or vice versa. Larger inversions result in smaller unbalanced distal segments and a higher likelihood of a viable fetus. In these cases the structure of the recombinant chromosome is similar to the original balanced inverted or normal ones despite the (unbalanced) genetic content. Such cases may not be detected prenatally by conventional cytogenetic analysis. Methods In all prenatal samples from the pericentric inversion carriers we applied subtelomeric FISH probes specific for the chromosome involved in order to detect parental meiotic recombinants resulting from a single cross-over event. Confirmatory MLPA was also applied in unbalanced fetuses. Results The occurrence of a duplication deficiency unbalance from pericentric inversion carriers was successfully detected in all three fetuses by FISH. MLPA assays applied in two cases confirmed these results. Conclusions The application of commercial FISH subtelomeric probes is a reliable method that could be routinely applied for the detection of single cross-over meiotic recombinants. MLPA is a sound alternative technique.

Anti-forensics is the practice of circumventing classical forensics analysis procedures making them either unreliable or impossible. In this paper we propose the use of machine learning algorithms and anomaly detection to cope with a wide class of definitive anti-forensics techniques. We test the proposed system on a dataset we created through the implementation of an innovative technique of anti-forensics, and we show that our approach yields promising results in terms of detection.

Flocculation of suspended cohesive sediment, well-known to impact the floc size distribution and vertical fluxes, and cause morphodynamic changes of marine and riverine environments, is modelled by means of a population balance equation that implements a novel description of floc geometry: the capacity dimension of fractal flocs, normally assumed constant over the population, has recently been argued to change during flocculation. Our experiments have shown that a power-law function of the dimensionless floc size can conveniently be used to describe these changes. This description of floc capacity dimension is used to explore in detail the extent to which the geometrical properties of flocs affect aggregation and breakup processes, and contribute to shaping their size distribution. A comparison of experimental floc size distributions from settling column test with computed distributions for two hypotheses of floc capacity dimension (i.e., constant and variable) and two hypotheses of flocculation reactions (i.e., semi-stochastic and deterministic) are shown. This suggests that the use of variable rather than constant floc capacity dimension, and the use of semi-stochastic and asymmetric reactions rather than deterministic and symmetric, result in better predictions of the floc size distribution in the environmental conditions herein analysed.

Android introduced the dynamic code loading (DCL) mechanism to allow for code reuse, to achieve extensibility, to enable updating functionalities, or to boost application start-up performance. In spite of its wide adoption by developers, previous research has shown that the secure implementation of DCL-based functionality is challenging, often leading to remote code injection vulnerabilities. Unfortunately, previous attempts to address this problem by both the academic and Android developers communities are affected by either practicality or completeness issues, and, in some cases, are affected by severe vulnerabilities. In this paper, we propose, design, implement, and test Grab 'n Run, a novel code verification protocol and a series of supporting libraries, APIs, and tools, that address the problem by abstracting away from the developer many of the challenging implementation details. Grab 'n Run is designed to be practical: Among its tools, it provides a drop-in library, which requires no modifications to the Android framework or the underlying Dalvik/ART runtime, is very similar to the native API, and most code can be automatically rewritten to use it. Grab 'n Run also contains an application-rewriting tool, which allows to easily port legacy or third-party applications to use the secure APIs developed in this work. We evaluate the Grab 'n Run library with a user study, obtaining very encouraging results in vulnerability reduction, ease of use, and speed of development. We also show that the performance overhead introduced by our library is negligible. For the benefit of the security of the Android ecosystem, we released Grab 'n Run as open source.

An experimental study was conducted to test the hypothesis that the biomass growing after an increase in available nutrient in an aquatic ecosystem affects the flocculation dynamics of suspended particulate matter (SPM). The experiment was carried out in a settling column equipped with a turbulence generating system, a water quality monitoring system, and an automated μPIV system to acquire micro photographs of SPM. Three SPM types were tested combinatorially at five turbulence shear rates, three nutrient concentrations, and three mineral concentrations. Analyses of experimental data showed that nutrient availability together with the presence of biomass increased the SPM size by about 60% at low shear as compared to nutrient- and biomass-free conditions; a lower increase was observed at higher shears. In contrast, only 2% lower fractal (capacity) dimension and nearly invariant settling velocity were observed than in nutrient- and biomass-free conditions. Likewise, SPM size and capacity dimension were found to be insensitive to the SPM concentration. Although limited to nearly homogeneous mineral mixes (kaolinite), these experimental findings not only reject the hypothesis that SPM in natural waters can be dealt with as purely mineral systems in all instances, but also anticipate that SPM dynamics in natural waters increasingly exposed to the threat of anthropogenic nutrient discharge would lead to an increased advective flow of adsorbed chemicals and organic carbon.

Cell-free DNA (cfDNA) screening can provide false positive/negative results because the fetal fraction originates primarily from trophoblast. Consequently, invasive diagnostic testing is recommended to confirm a high-risk result. Currently, there is debate about the most appropriate invasive method. We sought to estimate the frequency in which a chorionic villus sampling (CVS) performed after a high-risk cfDNA result would require a follow-up amniocentesis due to placental mosaicism.Analyses of the frequencies of the different types of mosaicism involving cytotrophoblasts, for trisomies 21 (T21), 18 (T18), 13 (T13) and monosomy X (MX) among 52,673 CVS karyotypes obtained from cytotrophoblast, mesenchyme and confirmatory amniocentesis.After a high-risk cfDNA result for T21, 18, 13 and MX, the likelihood of finding CVS mosaicism and need for amniocentesis is, respectively, 2%, 4%, 22% and 59%. When mosaicism is detected by CVS, the likelihood of fetal confirmation by amniocentesis is, respectively, 44%, 14%, 4% and 26%.In cases of high-risk cfDNA results for T21/T18, CVS (combining cytotrophoblast and mesenchyme analysis) can be considered, but with the caveat of 2-4% risk of an inconclusive result requiring further testing. In high-risk results for MX/T13, amniocentesis would appear to be the most appropriate follow-up diagnostic test, especially in the absence of sonographic findings.

The implementation of chromosomal microarray analysis (CMA) in prenatal testing for all patients has not achieved a consensus. Technical alternatives such as Prenatal BACs-on-Beads(TM) (PNBoBs(TM) ) have thus been applied. The aim of this study was to provide the frequencies of the submicroscopic defects detectable by PNBoBs(TM) under different prenatal indications.A total of 9648 prenatal samples were prospectively analyzed by karyotyping plus PNBoBs(TM) and classified by prenatal indication. The frequencies of the genomic defects and their 95%CIs were calculated for each indication.The overall incidence of cryptic imbalances was 0.7%. The majority involved the DiGeorge syndrome critical region (DGS). The additional diagnostic yield of PNBoBs(TM) in the population with a low a priori risk was 1/298. The prevalences of DGS microdeletion and microduplication in the low-risk population were 1/992 and 1/850, respectively.The constant a priori risk for common pathogenic cryptic imbalances detected by this technology is estimated to be ~0.3%. A prevalence higher than that previously estimated was found for the 22q11.2 microdeletion. Their frequencies were independent of maternal age. These data have implications for cell-free DNA screening tests design and justify prenatal screening for 22q11 deletion, as early recognition of DGS improves its prognosis.

In ransomware attacks, the actual target is the human, as opposed to the classic attacks that abuse the infected devices e.g., botnet renting, information stealing. Mobile devices are by no means immune to ransomware attacks. However, there is little research work on this matter and only traditional protections are available. Even state-of-the-art mobile malware detection approaches are ineffective against ransomware apps because of the subtle attack scheme. As a consequence, the ample attack surface formed by the billion mobile devices is left unprotected. First, in this work we summarize the results of our analysis of the existing mobile ransomware families, describing their common characteristics. Second, we present HelDroid, a fast, efficient and fully automated approach that recognizes known and unknown scareware and ransomware samples from goodware. Our approach is based on detecting the "building blocks" that are typically needed to implement a mobile ransomware application. Specifically, HelDroid detects, in a generic way, if an app is attempting to lock or encrypt the device without the user's consent, and if ransom requests are displayed on the screen. Our technique works without requiring that a sample of a certain family is available beforehand. We implemented HelDroid and tested it on real-world Android ransomware samples. On a large dataset comprising hundreds of thousands of APKs including goodware, malware, scareware, and ransomware, HelDroid exhibited nearly zero false positives and the capability of recognizing unknown ransomware samples.

Battery technology seems unable to keep up with the rapid evolution of smartphones and their applications, which continuously demand more and more energy. Modern smartphones, with their plethora of application scenarios and usage habits, are setting new challenges and constraints for malware detection software. Among these challenges, preserving the battery life as much as possible is one of the most pressing. From the end users' perspective, a security solution, such as an antivirus AV, that significantly impacts the battery's life is unacceptable. Thus, the quality and degree of adoption of malware-detection products is also influenced by their energy demands. Motivated by the above rationale, we perform the first fine-grained measurement that analyzes, at a low level, the energy efficiency of modern, commercial, popular AVs. We explore the relations between various aspects of popular AVs, when handling malicious and benign applications, and the resulting energy consumption. Even though we focus on energy consumption, we also explore other dimensions such as the discrepancies between scanning modes, the impact of file size and scan duration. We then translate our findings into a set of design guidelines for reducing the energy footprint of modern AVs for mobile devices.

The capabilities of modern devices, coupled with the almost ubiquitous availability of Internet connectivity, have resulted in photos being shared online at an unprecedented scale. This is further amplified by the popularity of social networks and the immediacy they offer in content sharing. Existing access control mechanisms are too coarse-grained to handle cases of conflicting interests between the users associated with a photo; stories of embarrassing or inappropriate photos being widely accessible have become quite common. In this paper, we propose to rethink access control when applied to photos, in a way that allows us to effectively prevent unwanted individuals from recognizing users in a photo. The core concept behind our approach is to change the granularity of access control from the level of the photo to that of a user's personally identifiable information (PII). In this work, we consider the face as the PII. When another user attempts to access a photo, the system determines which faces the user does not have the permission to view, and presents the photo with the restricted faces blurred out. Our system takes advantage of the existing face recognition functionality of social networks, and can interoperate with the current photo-level access control mechanisms. We implement a proof-of-concept application for Facebook, and demonstrate that the performance overhead of our approach is minimal. We also conduct a user study to evaluate the privacy offered by our approach, and find that it effectively prevents users from identifying their contacts in 87.35% of the restricted photos. Finally, our study reveals the misconceptions about the privacy offered by existing mechanisms, and demonstrates that users are positive towards the adoption of an intuitive, straightforward access control mechanism that allows them to manage the visibility of their face in published photos.

This paper presents an approach to process and analyse digital images of mud flocs recorded via optical techniques. Grey-scale images of mud flocs consist of bright spots on a dark background, the recordings being characterised by a bimodal intensity (luminosity) distribution. First, we propose a fast algorithm to separate such two-intensity regions to obtain black and white images via Gaussian-curve fitting. This algorithm is evaluated in its capability to recognise the mass distribution and perimeter segmentation of mud flocs. Next, we characterise these images of mud flocs by using the concepts of multifractality, entropy and symmetry. This approach gives indication that a complex behaviour rises in a population of mud flocs, which evolves far from equilibrium. Multifractal scaling and differentiation into dominant and rare geometrically featured flocs are inferred to mark the evolution of a population of cohesive sediment flocs. The mathematical tools and method of analysis presented here are applied to a small set of flocs. Despite this limitation, the results obtained here seem promising, and application of this approach to a wider data set is expected to advance the interpretation of flocculation and floc morphodynamics of suspended cohesive sediment.

Chromosome mosaicism is detected in about 1-2% of chorionic villi samples (CVS), and may be due to a postzygotic nondisjunction event generating a trisomic cell line in an initially normal conceptus (mitotic origin) or the postzygotic loss of one chromosome in an initially trisomic conceptus (meiotic origin and trisomy rescue). Depending on the distribution of the abnormal cell line, the mosaic can be confined to the placenta (CPM) or generalised to the fetus (TFM, true fetal mosaicism). Trisomy rescue could theoretically be associated with a 33.3% probability of uniparental disomy (UPD) in the fetus. The aim of this study was to determine the risk of fetal involvement in a cohort of numerical and structural chromosome mosaics revealed in chorionic villi by means of combined direct and long-term culture analyses; we also determined the incidence of UPD associated with mosaic aneuploidies and supernumerary markers involving imprinted chromosomes. A total of 273 of a consecutive series of 15,109 CVS evaluated during a period of 5 years showed a mosaic condition in direct preparations and/or long-term cultures; confirmatory amniocentesis was performed in 203 cases. The abnormal cell line was extended to the fetus in 12.8% cases in terms of structural and numerical abnormalities involving autosomes and sex chromosomes; the risk of TFM varied and depended on the placental tissue distribution of the abnormal cell line. One of the 51 cases in which the mosaic involved an imprinted chromosome showed UPD, thus indicating a risk of 1.96%.

Objectives The presence in the conceptus of a Robertsonian translocation predisposes to UPD formation, mainly by post-zygotic events of chromosome abnormality rescue. This is due to the increased risk of generating aneuploid zygotes because the rearranged chromosome and the respective homologues are prone to nondisjunction errors. Given this, carriers and karyotypically normal individuals conceived from a parent with a Robertsonian translocation are at risk for UPD. Abnormal phenotypes due to an imprinting effect have been found to be associated with UPD 14 and 15. The aim of the study was to refine, at the time of prenatal diagnosis, the risk for UPD 14 and 15 in a population with Robertsonian translocations involving these chromosomes. Methods Sixty-five cases of familial and de novo heterologous Robertsonian translocations involving chromosomes 14 and 15 and 18 fetuses with a normal karyotype, but conceived by a Robertsonian translocation carrier were prenatally studied to investigate the presence of UPD for chromosomes 14 and 15. Results Of the 65 Robertsonian translocation carriers, one fetus with a de novo der(14;21) showed maternal UPD 14. None of the 18 fetuses with a normal karyotype had UPD. Conclusion Our data, combined with other previous prenatal investigations provide a general risk estimate for UPD 14 and 15 of 0.6%. Nevertheless, combining our data and those previously reported, all three fetuses with UPD had a de novo Robertsonian translocation, thus suggesting a risk of UPD formation of about 3% for this specific group of translocation carriers. Copyright  2004 John Wiley & Sons, Ltd.

Building automation systems rely heavily on general-purpose computers and communication protocols, which are often affected by security vulnerabilities. In this paper, we first analyze the attack surface of a real building automation system - based on the widely used KNX protocol-connected to a general-purpose IP network. To this end, we analyze the vulnerabilities of KNX-based networks highlighted by previous research work, which, however, did not corroborate their findings with experimental results. To verify the practical exploitability of these vulnerabilities and their potential impact, we implement a full-fledged testbed infrastructure that reproduces the typical deployment of a building automation system. On this testbed, we show the feasibility of a practical attack that leverages and combines the aforementioned vulnerabilities. We show the ease of reverse engineering the vendor-specific components of the KNX protocol. Our attack leverages the IP-to-KNX connectivity to send arbitrary commands which are executed by the actuators. We conclude that the vulnerabilities highlighted by previous work are effectively exploitable in practice, with severe results. Although we use KNX as a target, our work can be generalized to other communication protocols, often characterized by similar issues. Finally, we analyze the countermeasures proposed in previous literature and reveal the limitations that prevent their adoption in practice. We suggest a practical stopgap measure to protect real KNX-based BASs from our attack.

We describe our experience gained while exploring practical security and privacy problems in a real-world, large- scale social network (i.e., Facebook), and summarize our conclusions in a series of "lessons learned". We first conclude that it is better to adequately describe the potential ethical concerns from the very beginning and plan ahead the institutional review board (IRB) request. Even though sometimes optional, the IRB approval is a valuable point from the reviewer's perspective. Another aspect that needs planning is getting in touch with the online social network security team, which takes a substantial amount of time. With their support, "bending the rules" (e.g., using scrapers) when the experimental goals require so, is easier. Clearly, in cases where critical technical vulnerabilities are found during the research, the general recommendations for responsible disclosure should be followed. Gaining the audience's engagement and trust was essential to the success of our user study. Participants felt more comfortable when subscribing to our experiments, and also responsibly reported bugs and glitches. We did not observe the same behavior in crowd-sourcing workers, who were instead more interested in obtaining their rewards. On a related point, our experience suggests that crowd sourcing should not be used alone: Setting up tasks is more time consuming than it seems, and researchers must insert some sentinel checks to ensure that workers are not submitting random answers.From a logistics point of view, we learned that having at least a high-level plan of the experiments pays back, especially when the IRB requires a detailed description of the work and the data to be collected. However, over planning can be dangerous because the measurement goals can change dynamically. From a technical point of view, partially connected to the logistics remarks, having a complex and large data-gathering and analysis framework may be counterproductive in terms of set-up and management overhead. From our experience we suggest to choose simple technologies that scale up if needed but, more importantly, can scale down. For example, launching a quick query should be straightforward, and the frameworks should not impose too much overhead for formulating it. We conclude with a series of practical recommendations on how to successfully collect data from online social networks (e.g., using techniques for network multipresence, mimicking user behavior, and other crawling "tricks"') and avoid abusing the online service, while gathering the data required by the experiments.

Modern trojans are equipped with a functionality, called WebInject, that can be used to silently modify a web page on the infected end host. Given its flexibility, WebInject-based malware is becoming a popular information-stealing mechanism. In addition, the structured and well-organized malware-as-a-service model makes revenue out of customization kits, which in turns leads to high volumes of binary variants. Analysis approaches based on memory carving to extract the decrypted webinject.txt and config.bin files at runtime make the strong assumption that the malware will never change the way such files are handled internally, and therefore are not future proof by design. In addition, developers of sensitive web applications (e.g., online banking) have no tools that they can possibly use to even mitigate the effect of WebInjects.

URL shortening services facilitate the need of exchanging long URLs using limited space, by creating compact URL aliases that redirect users to the original URLs when followed. Some of these services show advertisements (ads) to link-clicking users and pay a commission of their advertising earnings to link-shortening users. In this paper, we investigate the ecosystem of these increasingly popular ad-based URL shortening services. Even though traditional URL shortening services have been thoroughly investigated in previous research, we argue that, due to the monetary incentives and the presence of third-party advertising networks, ad-based URL shortening services and their users are exposed to more hazards than traditional shortening services. By analyzing the services themselves, the advertisers involved, and their users, we uncover a series of issues that are actively exploited by malicious advertisers and endanger the users. Moreover, next to documenting the ongoing abuse, we suggest a series of defense mechanisms that services and users can adopt to protect themselves. ispartof: pages:51-62 ispartof: Proceedings of the 23rd International World Wide Web Conference (WWW 2014) pages:51-62 ispartof: World Wide Web Conference location:Seoul, Korea date:7 Apr - 11 Apr 2014 status: published

Chronic myeloid leukemia (CML) is a hematopoietic stem cell disorder included in the broader diagnostic category of myeloproliferative neoplasms, associated with fusion by BCR gene at chromosome 22q11 to ABL1 gene at chromosome 9q34 with the formation of the Philadelphia (Ph) chromosome. In 2–10% of CML cases, the fusion gene arises in connection with a variant translocation, involving chromosomes 9, 22, and one or more different chromosomes; consequently, the Ph chromosome could be masked within a complex chromosome rearrangement. In cases with variant Ph translocation a deletion on der(9) may be more frequently observed than in cases with the classical one. Herein we describe a novel case of CML with complex variant Ph translocation involving chromosomes 9, 12, and 22. We present the hematologic response and cytogenetic response after Imatinib treatment. We also speculated the mechanism which had originated the chromosome rearrangement.

We propose a semi-supervised online banking fraud analysis and decision support approach. During a training phase, it builds a profile for each customer based on past transactions. At runtime, it supports the analyst by ranking unforeseen transactions that deviate from the learned profiles. It uses methods whose output has a immediate statistical meaning that provide the analyst with an easy-to-understand model of each customer’s spending habits. First, we quantify the anomaly of each transaction with respect to the customer historical profile. Second, we find global clusters of customers with similar spending habits. Third, we use a temporal threshold system that measures the anomaly of the current spending pattern of each customer, with respect to his or her past spending behavior. As a result, we mitigate the undertraining due to the lack of historical data for building of well-trained profiles (of fresh users), and the users that change their (spending) habits over time. Our evaluation on real-world data shows that our approach correctly ranks complex frauds as “top priority”.

In an effort to hinder attackers from compromising user accounts, Facebook launched a form of two-factor authentication called social authentication (SA), where users are required to identify photos of their friends to complete a log-in attempt. Recent research, however, demonstrated that attackers can bypass the mechanism by employing face recognition software. Here we demonstrate an alternative attack. that employs image comparison techniques to identify the SA photos within an offline collection of the users' photos. In this paper, we revisit the concept of SA and design a system with a novel photo selection and transformation process, which generates challenges that are robust against these attacks. The intuition behind our photo selection is to use photos. that fail software-based face recognition, while remaining recognizable to humans who are familiar with the depicted people. The photo transformation process. creates challenges in the form of photo collages, where faces are transformed so as to render image matching techniques ineffective. We experimentally confirm the robustness of our approach against three template. matching algorithms that solve 0.4% of the challenges, while requiring four orders of magnitude more processing effort. Furthermore, when the transformations are applied, face detection software fails to detect even a single face. Our user studies confirm that users are able to identify their friends in over 99% of the photos with faces unrecognizable by software, and can solve over 94\% of the challenges with transformed photos.

A set of experiments was carried out to characterize how temperature affects the spread of chrysanthemum yellows phytoplasma (CYP), a strain of Candidatus Phytoplasma asteris, in Chrysanthemum carinatum plants transmitted by the Macrosteles quadripunctulatus leafhopper. Experiments provided data on CYP latency period in insect and plant host, M. quadripunctulatus adult mortality rate, and epidemics progression in plants under controlled conditions inside climatic chambers. Experiments were conducted at temperatures ranging between 15 and 30°C. Empirical laws for temperature-dependent epidemiological parameters were next derived and used in a dynamical model of the epidemics progression. Experiments showed that CYP epidemics was faster at higher temperatures and the model could replicate these observations with relatively high accuracy (correlation >98.03% and residuals M. quadripunctulatus at higher temperatures.

Insect-borne plant diseases recur commonly in wild plants and in agricultural crops, and are responsible for severe losses in terms of produce yield and monetary return. Mathematical models of insect-borne plant diseases are therefore an essential tool to help predicting the progression of an epidemic disease and aid in decision making when control strategies are to be implemented in the field. While retaining a generalized applicability of the proposed model to plant epidemics vectored by insects, we specifically investigated the epidemics of Flavescence dor\'ee phytoplasma (FD) in grapevine plant Vitis vinifera specifically transmitted by the leafhopper Scaphoideus titanus. The epidemiological model accounted for life-cycle stage of S. titanus, FD pathogen cycle within S. titanus and V. vinifera, vineyard setting, and agronomic practices. The model was comprehensively tested against biological S. titanus life cycle and FD epidemics data collected in various research sites in Piemonte, Italy, over multiple years. The work presented here represents a unique suite of governing equations tested on existing independent data and sets the basis for further modelling advances and possible applications to investigate effectiveness of real-case epidemics control strategies and scenarios.

A dynamic model of "flavescence dorée" phytoplasma (FD) in grapevine transmitted by the leafhopper Scaphoideus titanus was developed and tested. The model accounted for the biological life cycle of S. titanus on Vitis vinifera, epidemics progression in V. vinifera, vineyard setting, and agronomic practices aimed to control the epidemics. It was comprehensively tested against data sets of FD presence gathered in various vineyards in Piemonte, Italy, over nine years. The model achieved a correlation coefficient (R) and residual (NRMSE) against observations in the range R >= 91.3% and NRMSE

Modern botnets rely on domain-generation algorithms (DGAs) to build resilient command-and-control infrastructures. Given the prevalence of this mechanism, recent work has focused on the analysis of DNS traffic to recognize botnets based on their DGAs. While previous work has concentrated on detection, we focus on supporting intelligence operations. We propose Phoenix, a mechanism that, in addition to telling DGA- and non-DGA-generated domains apart using a combination of string and IP-based features, characterizes the DGAs behind them, and, most importantly, finds groups of DGA-generated domains that are representative of the respective botnets. As a result, Phoenix can associate previously unknown DGA-generated domains to these groups, and produce novel knowledge about the evolving behavior of each tracked botnet. We evaluated Phoenix on 1,153,516 domains, including DGA-generated domains from modern, well-known botnets: without supervision, it correctly distinguished DGA- vs. non-DGA-generated domains in 94.8 percent of the cases, characterized families of domains that belonged to distinct DGAs, and helped researchers “on the field” in gathering intelligence on suspicious domains to identify the correct botnet.

Compared to traditional desktop software, Android applications are delivered through software repositories, commonly known as application markets. Other mobile platforms, such as Apple iOS and BlackBerry OS also use the marketplace model, but what is unique to Android is the existence of a plethora of alternative application markets. This complicates the task of detecting and tracking Android malware. Identifying a malicious application in one particular market is simply not enough, as many instances of this application may exist in other markets. To quantify this phenomenon, we exhaustively crawled 8 markets between June and November 2013. Our findings indicate that alternative markets host a large number of ad-aggressive apps, a non-negligible amount of malware, and some markets even allow authors to publish known malicious apps without prompt action.

We present an analysis of the effect of the temperature on the flow of multiphase systems made of multiple miscible components in uniform cylindrical capillaries in adiabatic conditions. The temperature was explicitly included in the dynamic contact angle, tension at the three-phase contact line, and densities and viscosities of the fluids. The mathematical framework accounted for conservative forces (gravity, inertial, and interfacial tensions), nonconservative forces (viscous dissipation), and fluid retardation effects in the reservoirs at the two capillary ends. Temperature-dependent flow regimes ranged from nonoscillatory to oscillatory in a two-phase binary liquid (water-ethanol) system and in a two-phase pure liquid (ether) system. The Ca-Bo orbits highlighted dynamic attractors that depended on specific system characteristics as well as temperature. We conclude that temperature alone expresses and important role in the dynamical characteristics of capillary rise flow around its equilibrium.

Although there are controversial opinions regarding how large the mobile malware phenomenon is in terms of absolute numbers, hype aside, the amount of new Android malware variants is increasing. This trend is mainly due to the fact that, as it happened with traditional malware, the authors are striving to repackage, obfuscate, or otherwise transform the executable code of their malicious apps in order to evade mobile security apps. There are about 85 of these apps only on the official marketplace. However, it is not clear how effective they are. Indeed, the sandboxing mechanism of Android does not allow (security) apps to audit other apps.We present AndroTotal, a publicly available tool, malware repository and research framework that aims at mitigating the above challenges, and allow researchers to automatically scan Android apps against an arbitrary set of malware detectors. We implemented AndroTotal and released it to the research community in April 2013. So far, we collected 18,758 distinct submitted samples and received the attention of several research groups (1,000 distinct accounts), who integrated their malware-analysis services with ours.

Noninvasive prenatal screening for fetal aneuploidy analyzes cell-free fetal DNA circulating in the maternal plasma. Because cell-free fetal DNA is mainly of placental trophoblast origin, false-positive and false-negative findings may result from placental mosaicism. The aim of this study was to calculate the potential contribution of placental mosaicism in discordant results of noninvasive prenatal screening.We performed a retrospective audit of 52,673 chorionic villus samples in which cytogenetic analysis of the cytotrophoblast (direct) and villus mesenchyme (culture) was performed, which was followed by confirmatory amniocentesis in chorionic villi mosaic cases. Using cases in which cytogenetic discordance between cytotrophoblast and amniotic fluid samples was identified, we calculated the potential contribution of cell line-specific mosaicism to false-positive and false-negative results of noninvasive prenatal screening.The false-positive rate, secondary to the presence of abnormal cell line with common trisomies in cytotrophoblast and normal amniotic fluid, ranged from 1/1,065 to 1/3,931 at 10% and 100% mosaicism, respectively; the false-negative rate was calculated from cases of true fetal mosaicism, in which a mosaic cell line was absent in cytotrophoblast and present in the fetus; this occurred in 1/107 cases.Despite exciting advances, underlying biologic mechanisms will never allow 100% sensitivity or specificity.

An approach based on spheropolygons (i.e., the Minkowski sum of a polygon with N vertices and a disk with spheroradius r) is presented to describe the shape of kaolinite aggregates in water and to investigate interparticle collision dynamics. Spheropolygons generated against images of kaolinite aggregates achieved an error between 0.5% and 20% as compared to at least 32% of equivalent spheres. These spheropolygons were used to investigate the probability of collision (Pr[C]) and aggregation (Pr[A]) under the action of gravitational, viscous, contact (visco-elastic), electrostatic and van der Waals forces. In ortho-axial (i.e., frontal) collision, Pr[A] of equivalent spheres was always 1, however, stochastic analysis of collision among spheropolygons showed that Pr[A] decreased asymptotically with N increasing, and decreased further in peri-axial (i.e., tangential) collision. Trajectory analysis showed that not all collisions occurring within the attraction zone of the double layer resulted in aggregation, neither all those occurring outside it led to relative departure. Rather, the relative motion on surface asperities affected the intensity of contact and attractive forces to an extent to substantially control a collision outcome in either instances. Spheropolygons revealed therefore how external shape can influence particle aggregation, and suggested that this is equally important to contact and double layer forces in determining the probability of particle aggregation.

The risk of clinical consequences in prenatal cases with de novo small supernumerary marker chromosomes (sSMC), often in mosaic conditions, is not easy to predict, which results in difficulties in genetic counseling.In this study, we evaluated the frequency, the chromosomal origin, and the clinical indication of 104 de novo sSMC detected in a monocenter survey on the basis of 143,000 consecutive prenatal diagnoses, and we assessed the reliability of molecular cytogenetics technologies for sSMC characterization.We detected a de novo sSMC frequency of 0.072%. Its incidence in advanced maternal age group is statistically different from that found in maternal anxiety indication (35 years old). A higher prevalence of mosaicism in chorionic villi sampling (CVS) than in amniotic fluids was also revealed related to confined placental mosaicisms. The risk of confirmation in amniotic fluids of mosaics previously revealed at CVS was 33.3%. No uniparental disomy conditions were found when imprinted chromosomes were involved in the occurrence of de novo sSMC. The majority of de novo sSMC were acrocentric derived-chromosomes, and a neocentromere formation was observed in one pregnancy.Our data support that array comparative genomic hybridization has improved sSMC characterization and demonstrate its utility in supporting genetic counseling. We propose a workflow for de novo sSMC characterization.

This study proposes a comprehensive reaction network of the soil microbial breakdown of the main compounds in human urine to the end products NH₃ and NH₄⁺. A reactive model was developed and parameters were determined against experimental data. The model was used to assess the amount and release rate of NH₃ and NH₄⁺ in a soil control volume flushed with (i) pulses of urine at various dilutions and (ii) a continuous flow of urine at various dilutions and flow rates. In scenario i, 90% of incoming organic nitrogen was converted to NH₃ and NH₄⁺ between 5 and 20 days from application at rates strongly dependent on the initial microbial soil content. Urea and hippuric acid were largely correlated to NH₃ and NH₄⁺ release, whereas microbial functional groups in the same scenarios were poorly correlated with NH₃ and NH₄⁺ release. In scenario ii, 90% conversion was generally reached for low flow rates and was highly nonlinear with the dilution. Finally, a stochastic analysis showed that urine decomposition was more sensitive to uncertainty in microbial growth rate parameters than half-saturation concentrations.

We present a population model of the insect Scaphoideus titanus Ball, the leafhopper vector of Flavescence Doree phytoplasma in Vitis vinifera L. The model accounted for the stage-dependent S. titanus life cycle rates and timing, and vineyard settings such as surface area, plant density, and sampling characteristics. The model parameters were estimated against 13 independent cases of population counting in both laboratory and field conditions, and returned a correlation coefficient in the range 86.4 to 99.1% with residuals in the range 3.5 to 26.3%. A statistical parametric analysis showed that the standard deviation of life cycle rates generally varied more than the one resulting from timing parameters. However, a stochastic sensitivity analysis showed that S. titanus dynamics were more susceptible to variations in timing than rate parameters. Analysis of scenarios of insecticide suppression efficiency and timing showed that S. titanus presence could be optimally controlled by a combination of suppression efficiency and timing. These results were instrumental to understand in which specific aspect of S. titanus life cycle could pest management operations be most effective to reduce S. titanus presence in vineyards, and possibly reduce the risk of Flavescence phytoplasma spread.

We describe water movement and retention using the discrete element method in view of future modelling of partially saturated granular materials. By defining the water potential in terms of capillary bridges at low saturation, and in terms of pressure of entrapped air at high saturation, we investigate the hysteresis of water retention in granular materials during wetting and drainage. These phenomena are successfully underpinned by our model thanks to an equation that determines the local evolution of liquid-solid contact angles at the level of pores and grains.

Pericentric inversion of chromosome 4 can give rise to recombinant chromosomes by duplication or deletion of 4p. We report on a familial case of Wolf-Hirschhorn Syndrome characterized by GTG-banding karyotypes, FISH, and array CGH analysis, caused by a recombinant chromosome 4 with terminal 4p16.3 deletion and terminal 4q35.2 duplication. This is an aneusomy due to a recombination which occurred during the meiosis of heterozygote carrier of cryptic pericentric inversion. We also describe the adulthood and prenatal phenotypes associated with the recombinant chromosome 4.

Fetal karyotyping of trophoblast cells obtained by lavage of the uterine cavity was evaluated on 86 first-trimester irrigation fluid samples. Villus fragments were observed in 72 fluid samples indicating an 83.7 per cent sampling success rate. The amount of villi in these samples ranged from 1 to 32 mg. In most cases, villus fragments showed degeneration of the external syncytiotrophoblast layer and absence of blood vessels. In the first phase of this study (15 samples), a high degree of maternal cell contamination was observed after long-term cultures. In the following phase (71 samples), this obstacle was overcome by the application of a semi-direct method. Chromosome preparations were set up after 24 h incubation of villus fragments and QFQ-banded metaphase spreads were scored for chromosome number and sex. Sixty samples showed the presence of villus fragments and the fetal karyotype was established in 40. Male and female chromosome complements were observed in 16 and 24 cases, respectively. In four cases, an abnormal fetal karyotype was diagnosed. These included trisomy of chromosomes 13, 15, and 16, and one mosaic with trisomy 12. Our results indicate that first-trimester fetal karyotyping might be feasible by a semi-direct method using chorionic villus fragments obtained at intrauterine lavage.

Karyotyping is a well-established method of investigating the genetic content of product of conceptions (POCs). Because of the high rate of culture failure and maternal cell contamination, failed results or 46,XX findings are often obtained. Different molecular approaches that are not culture dependent have been proposed to circumvent these limits. On the basis of the robust experience previously obtained with bacterial artificial chromosomes (BACs)-on-Beads™ (BoBs™), we evaluated the same technology that we had used for the analysis of prenatal samples on POCs.KaryoLite™ BoBs™ includes 91 beads, each of which is conjugated with a composite of multiple neighboring BACs according to the hg19 assembly. It quantifies proximal and terminal regions of each chromosome arm. The study included 376 samples.The failure rate was 2%, and reproducibility99%; false-positive and false-negative rates were1% for non-mosaic aneuploidies and imbalances effecting all three BACs in a contig. Detection rate for partial terminal imbalances was 65.5%. The mosaic detection threshold was 50%, and the success rate in macerated samples was 87.8%. The aneuploidy detection rate in samples with cell growth failure was 27.8%, and maternal cell contamination was suspected in 23.1% of 46,XX cultured cells.KaryoLite™ BoBs™ as a 'first-tier' test in combination with other approaches showed beneficial, cost-effective and clearly enhanced POC testing.

Hyporheic exchanges in riparian zones induced by stream stage fluctuations, referred to as bank storage, can influence contaminant transport and transformation when mixing of groundwater and surface waters with distinct chemical signatures occur, which might lead to a high biochemical activity. The effect of bank storage on nutrient transport was analyzed here using a two-dimensional, variably saturated and multi-species reactive transport model, which accounted for the water flow and solute transport and reactions within riparian zones. After verification with field observations, our model demonstrated that high biogeochemical activities occurred at the near-stream riparian zone during stage fluctuation, a process referred to as bank storage hot moment (BSHM). We used Monte Carlo simulations to study the uncertainty of BSHM and related nutrient dynamics to biogeochemical and hydrological factors. The results indicated that stream fluctuations can lead to maximum bank storage volume ranging from 0 to 259 m3 m1 of stream linear length (median ¼ 9.7 m3 and SD ¼ 53.2 m3). Taking denitrification as an example, BSHM can lead to considerable NO3 removal with a median removal rate of 2.1 g d1 and SD of 17.2 g d1 per meter of stream linear length. The NO3 uptake velocity (median ¼ 2.7 105 and SD ¼ 2.4 104 mmin1) was comparable to that of in-stream transient storage from the literature. This result suggests that BSHM may be a significant process contributing to the nutrient budget at the ecosystem level. Finally, a theoretical framework representing the coupled hydrobiogeochemical controls on riparian hot spots was developed to help predicting when BSHM can become important in a particular stream.

Earlier experiments demonstrated that isotopic effects during nitrification, denitrification and dissimilatory nitrate reduction can be affected by high (15) N contents. These findings call into question whether the reaction parameters (rate constants and Michaelis-Menten concentrations) are function of δ(15) N values, and if these can also lead to significant effects on the bulk reaction rate.Five experiments at initial δ(15) N-NO(3) (-) values ranging from 0‰ to 1700‰ were carried out in a recent study using elemental analyser, gas chromatography, and mass spectrometry techniques coupled at various levels. These data were combined here with kinetic equations of isotopologue speciation and fractionation. Our approach specifically addressed the combinatorial nature of reactions involving labeled atoms and explicitly described substrate competition and time-dependent isotopic effects.With the method presented here, we determined with relatively high accuracy that the reaction rate constants increased linearly up to 270% and the Michaelis-Menten concentrations decreased linearly by about 30% over the tested δ(15) N-NO(3) (-) values. Because the parameters were found to depend on the (15) N enrichment level, we could determine that increasing δ(15) N-NO(3) (-) values caused a decrease in bulk nitrification, denitrification and dissimilatory nitrate reduction rates by 50% to 60%.We addressed a method that allowed us to quantify the effect of substrate isotopic enrichment on the reaction kinetics. Our results enable us to reject the assumption of constant reaction parameters. The implications of δ-dependent (variable) reaction parameters extend beyond the study-case analysed here to all instances in which high and variable isotopic enrichments occur.

Two-factor authentication is widely used by high-value services to prevent adversaries from compromising accounts using stolen credentials. Facebook has recently released a two-factor authentication mechanism, referred to as Social Authentication, which requires users to identify some of their friends in randomly selected photos. A recent study has provided a formal analysis of social authentication weaknesses against attackers inside the victim's social circles. In this paper, we extend the threat model and study the attack surface of social authentication in practice, and show how any attacker can obtain the information needed to solve the challenges presented by Facebook. We implement a proof-of-concept system that utilizes widely available face recognition software and cloud services, and evaluate it using real public data collected from Facebook. Under the assumptions of Facebook's threat model, our results show that an attacker can obtain access to (sensitive) information for at least 42% of a user's friends that Facebook uses to generate social authentication challenges. By relying solely on publicly accessible information, a casual attacker can solve 22% of the social authentication tests in an automated fashion, and gain a significant advantage for an additional 56% of the tests, as opposed to just guessing. Additionally, we simulate the scenario of a determined attacker placing himself inside the victim's social circle by employing dummy accounts. In this case, the accuracy of our attack greatly increases and reaches 100% when 120 faces per friend are accessible by the attacker, even though it is very accurate with as little as 10 faces.