180 research outputs found
Privacy Preserving Internet Browsers: Forensic Analysis of Browzar
With the advance of technology, Criminal Justice agencies are being
confronted with an increased need to investigate crimes perpetuated partially
or entirely over the Internet. These types of crime are known as cybercrimes.
In order to conceal illegal online activity, criminals often use private
browsing features or browsers designed to provide total browsing privacy. The
use of private browsing is a common challenge faced in for example child
exploitation investigations, which usually originate on the Internet. Although
private browsing features are not designed specifically for criminal activity,
they have become a valuable tool for criminals looking to conceal their online
activity. As such, Technological Crime units often focus their forensic
analysis on thoroughly examining the web history on a computer. Private
browsing features and browsers often require a more in-depth, post mortem
analysis. This often requires the use of multiple tools, as well as different
forensic approaches to uncover incriminating evidence. This evidence may be
required in a court of law, where analysts are often challenged both on their
findings and on the tools and approaches used to recover evidence. However,
there are very few research on evaluating of private browsing in terms of
privacy preserving as well as forensic acquisition and analysis of privacy
preserving internet browsers. Therefore in this chapter, we firstly review the
private mode of popular internet browsers. Next, we describe the forensic
acquisition and analysis of Browzar, a privacy preserving internet browser and
compare it with other popular internet browser
Correlation of Positron Emission Tomography/Computed Tomography Scan with Smoking, Tumor Size, Stage and Differentiation in Head and Neck Cancer Patients
The goal of this study was to identify associations between positron emission tomography/computed tomography (PET/CT) maximum standardized uptake value (SUVmax) in patients presenting with head and neck squamous cell carcinoma (SCC) with tumor site, size, histologic differentiation, smoking, and diabetes. Charts of patients with oropharyngeal and laryngeal SCC who underwent 18F-fluorodeoxyglucose PET/CT scans were reviewed between May 2007 and August 2013. Statistical analyses included modeling log-transformed SUVmax values by tumor site, size, histologic differentiation, smoking status, and diabetes using unadjusted linear regressions. Differences were considered statistically significant for P\u3c 0.05. A total of 111 patients (54 with oropharynx and 57 with larynx cancers) were included, 83 men and 28 women with an average age of 57.5 years old. There was a significantly higher pack-year smoking history (P = 0.005) in the larynx cancer group. While tumor T-stage was found to be significantly different (P \u3c 0.0001), there was no difference in tumor size between the two groups: 3.16 cm and 3.58 cm in the oropharynx and larynx, respectively (P = 0.55). In the oropharynx cohort, SUVmax was associated with both tumor size (P = 0.0001) and stage (P \u3c 0.0002). Interestingly, SUVmax differed by tumor differentiation in the larynx (P = 0.04) but not the oropharynx (P = 0.71). Finally, there was no significant difference in SUVmax relative to diabetes and smoking status. PET/CT SUVmax correlated with both tumor size and stage in oropharyngeal cancer patients, and it correlated only with tumor differentiation but not the size or stage in the larynx. There were no significant differences in SUVmax by diabetes or smoking status
Cognitive Task Demands Modulate the Sensitivity of the Human Cochlea
Recent studies lead to the conclusion that focused attention, through the activity of corticofugal and medial olivocochlear (MOC) efferent pathways, modulates activity at the most peripheral aspects of the auditory system within the cochlea. In two experiments, we investigated the effects of different intermodal attention manipulations on the response of outer hair cells (OHCs), and the control exerted by the MOC efferent system. The effect of the MOCs on OHC activity was characterized by measuring the amplitude and rapid adaptation time course of distortion product otoacoustic emissions (DPOAEs). In the first, DPOAE recordings were compared while participants were reading a book and counting the occurrence of the letter “a” (auditory-ignoring) and while counting either short- or long-duration eliciting tones (auditory-attending). In the second, DPOAEs were recorded while subjects watched muted movies with subtitles (auditory-ignoring/visual distraction) and were compared with DPOAEs recorded while subjects counted the same tones (auditory-attending) as in Experiment 1. In both Experiments 1 and 2, the absolute level of the averaged DPOAEs recorded during the auditory-ignoring condition was statistically higher than that recorded in the auditory-attending condition. Efferent-induced rapid adaptation was evident in all DPOAE contours, under all attention conditions, suggesting that two medial efferent processes act independently to determine rapid adaptation, which is unaffected by attention, and the overall DPOAE level, which is significantly affected by changes in the focus of attention
Operative Management of Symptomatic, Metachronous Carotid Body Tumors Involving the Skull Base and Its Neurological Sequelae
A 44-year-old morbidly obese woman with a history of right carotid body tumor (CBT) resection presented with a symptomatic, nonfunctional, left Shamblin-III CBT. Abutment of the skull base precluded distal internal carotid artery control for arterial reconstruction, favoring parent vessel sacrifice after an asymptomatic provocative test. She underwent CBT resection with anticipated sacrifice of cranial nerves X and XII and the common carotid artery and its branches, developing baroreceptor failure syndrome and sequelae of cranial nerve sacrifice. When facing a symptomatic, metachronous CBT abutting the skull base, upfront operative intervention with adjuvant radiation for residual tumor optimizes curative resection
Market Segmentation Trees
Problem Definition: We seek to provide an interpretable framework for segmenting users in a population for personalized decision-making.
Methodology / Results: We propose a general methodology, Market Segmentation Trees (MSTs), for learning market segmentations explicitly driven by identifying differences in user response patterns. To demonstrate the versatility of our methodology, we design two new, specialized MST algorithms: (i) Choice Model Trees (CMTs), which can be used to predict a user’s choice amongst multiple options and (ii) Isotonic Regression Trees (IRTs), which can be used to solve the bid landscape forecasting problem. We provide a theoretical analysis of the asymptotic running times of our algorithmic methods, which validates their computational tractability on large datasets. We also provide a customizable, open-source code base for training MSTs in Python which employs several strategies for scalability, including parallel processing and warm starts. Finally, we assess the practical performance of MSTs on several synthetic and real world datasets, showing that our method reliably finds market segmentations which accurately model response behavior.
Managerial Implications: The standard approach to conduct market segmentation for personalized decision-making is to first perform market segmentation by clustering users according to similarities in their contextual features, and then fit a “response model” to each segment in order to model how users respond to decisions. However, this approach may not be ideal if the contextual features prominent in distinguishing clusters are not key drivers of response behavior. Our approach addresses this issue by integrating market segmentation and response modeling, which consistently leads to improvements in response prediction accuracy, thereby aiding personalization. We find that such an integrated approach can be computationally tractable and effective even on large-scale datasets. Moreover, MSTs are interpretable since the market segments can easily be described by a decision tree and often require only a fraction of the number of market segments generated by traditional approaches
Epithelial-mesenchymal plasticity determines estrogen receptor positive breast cancer dormancy and epithelial reconversion drives recurrence
More than 70% of human breast cancers (BCs) are estrogen receptor α-positive (ER+). A clinical challenge of ER+ BC is that they can recur decades after initial treatments. Mechanisms governing latent disease remain elusive due to lack of adequate in vivo models. We compare intraductal xenografts of ER+ and triple-negative (TN) BC cells and demonstrate that disseminated TNBC cells proliferate similarly as TNBC cells at the primary site whereas disseminated ER+ BC cells proliferate slower, they decrease CDH1 and increase ZEB1,2 expressions, and exhibit characteristics of epithelial-mesenchymal plasticity (EMP) and dormancy. Forced E-cadherin expression overcomes ER+ BC dormancy. Cytokine signalings are enriched in more active versus inactive disseminated tumour cells, suggesting microenvironmental triggers for awakening. We conclude that intraductal xenografts model ER + BC dormancy and reveal that EMP is essential for the generation of a dormant cell state and that targeting exit from EMP has therapeutic potential
Assortment optimisation under a general discrete choice model: A tight analysis of revenue-ordered assortments
The assortment problem in revenue management is the problem of deciding which
subset of products to offer to consumers in order to maximise revenue. A simple
and natural strategy is to select the best assortment out of all those that are
constructed by fixing a threshold revenue and then choosing all products
with revenue at least . This is known as the revenue-ordered assortments
strategy. In this paper we study the approximation guarantees provided by
revenue-ordered assortments when customers are rational in the following sense:
the probability of selecting a specific product from the set being offered
cannot increase if the set is enlarged. This rationality assumption, known as
regularity, is satisfied by almost all discrete choice models considered in the
revenue management and choice theory literature, and in particular by random
utility models. The bounds we obtain are tight and improve on recent results in
that direction, such as for the Mixed Multinomial Logit model by
Rusmevichientong et al. (2014). An appealing feature of our analysis is its
simplicity, as it relies only on the regularity condition.
We also draw a connection between assortment optimisation and two pricing
problems called unit demand envy-free pricing and Stackelberg minimum spanning
tree: These problems can be restated as assortment problems under discrete
choice models satisfying the regularity condition, and moreover revenue-ordered
assortments correspond then to the well-studied uniform pricing heuristic. When
specialised to that setting, the general bounds we establish for
revenue-ordered assortments match and unify the best known results on uniform
pricing.Comment: Minor changes following referees' comment
Superfluid to normal phase transition and extreme regularity of superdeformed bands
We derive the exact semiclassical expression for the second inertial
parameter for the superfluid and normal phases. Interpolation between
these limiting values shows that the function changes sign at the
spin , which is critical for a rotational spectrum. The quantity
turns out to be a sensitive measure of the change in static pairing
correlations. The superfluid-to-normal transition reveals itself in the
specific variation of the ratio versus spin with the
plateau characteristic of the normal phase. We find this dependence to be
universal for normal deformed and superdeformed bands. The long plateau with a
small value explains the extreme regularity of
superdeformed bands.Comment: 30 pages in LaTeX, 6 figures (PostScript). To be published in
Yadernaya Fizika (Physics of Atomic Nuclei), special edition dedecated to the
90th birthday of Prof. I. I. Gurevit
Femoral Shaft Fracture Occurring as a Result of Physical Manipulation: A Case Report
Treatments including physical manipulation maneuvers have been widely used for the management of various pain complaints. These maneuvers, although generally considered safe, can be associated with serious complications. We report the case of a 37-years-old previously healthy male patient, who presented to our emergency department (ED) for severe right thigh pain and inability to bear weight that developed during a chiropractic session. Imaging done at the ED showed a displaced distal femoral shaft fracture. The majority of the complications of manipulation maneuvers can be as simple as sprains, however, can be drastic or life-threatening in certain cases causing cerebrovascular accidents or major orthopedic fractures. Such complications are rare and definitely underreported. A femoral shaft fracture occurring as a result of physical manipulation has not been previously reported in the literature. We report a distal femoral shaft fracture that was induced by forceful chiropractic manipulation. It is the first to be reported in the literature. This complication should be noted, reported, and the necessary precautions are taken to avoid such major adverse events
- …