108 research outputs found
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The Limits of Location Privacy in Mobile Devices
Mobile phones are widely adopted by users across the world today. However, the privacy implications of persistent connectivity are not well understood. This dissertation focuses on one important concern of mobile phone users: location privacy.
I approach this problem from the perspective of three adversaries that users are exposed to via smartphone apps: the mobile advertiser, the app developer, and the cellular service provider. First, I quantify the proportion of mobile users who use location permissive apps and are able to be tracked through their advertising identifier, and demonstrate a mark and recapture attack that allows continued tracking of users who hide these identifiers. Ninety-five percent of the 1500 devices we tested were susceptible to this attack. We successfully identified 49% of unlabelled impressions from iOS devices, and 59% from Android, with a budget of only $5 per day, per user. Next, I evaluate an attack wherein a remote server discovers a user\u27s traveled path without permission, simply by analyzing the throughput of the connection to the user over time. In these experiments, a remote attacker can distinguish a user\u27s route among four paths within a University campus with 77% accuracy, and among eight paths surrounding the campus with 83% accuracy. I then propose a protocol for anonymous cell phone usage, which obviates the need for users to trust telecoms with their location, and I evaluate its efficacy against a passive location profiling attack used to infer identity. According to these simulations, even one day is enough to identify one device from among over a hundred with greater than 50% accuracy. To mitigate location profiling attacks, users should change these identifiers every ten minutes and remain offline for 30 seconds, to reduce their identifiability by up to 45%. I conclude by summarizing the key issues in mobile location privacy today, immediate steps that can be taken to improve them, and the inherent privacy costs of remaining constantly connected
The Impact of Anxiety-Inducing Distraction on Cognitive Performance: A Combined Brain Imaging and Personality Investigation
BACKGROUND: Previous investigations revealed that the impact of task-irrelevant emotional distraction on ongoing goal-oriented cognitive processing is linked to opposite patterns of activation in emotional and perceptual vs. cognitive control/executive brain regions. However, little is known about the role of individual variations in these responses. The present study investigated the effect of trait anxiety on the neural responses mediating the impact of transient anxiety-inducing task-irrelevant distraction on cognitive performance, and on the neural correlates of coping with such distraction. We investigated whether activity in the brain regions sensitive to emotional distraction would show dissociable patterns of co-variation with measures indexing individual variations in trait anxiety and cognitive performance. METHODOLOGY/PRINCIPAL FINDINGS: Event-related fMRI data, recorded while healthy female participants performed a delayed-response working memory (WM) task with distraction, were investigated in conjunction with behavioural measures that assessed individual variations in both trait anxiety and WM performance. Consistent with increased sensitivity to emotional cues in high anxiety, specific perceptual areas (fusiform gyrus--FG) exhibited increased activity that was positively correlated with trait anxiety and negatively correlated with WM performance, whereas specific executive regions (right lateral prefrontal cortex--PFC) exhibited decreased activity that was negatively correlated with trait anxiety. The study also identified a role of the medial and left lateral PFC in coping with distraction, as opposed to reflecting a detrimental impact of emotional distraction. CONCLUSIONS: These findings provide initial evidence concerning the neural mechanisms sensitive to individual variations in trait anxiety and WM performance, which dissociate the detrimental impact of emotion distraction and the engagement of mechanisms to cope with distracting emotions. Our study sheds light on the neural correlates of emotion-cognition interactions in normal behaviour, which has implications for understanding factors that may influence susceptibility to affective disorders, in general, and to anxiety disorders, in particular
Group Music Intervention Reduces Aggression and Improves Self-esteem in Children with Highly Aggressive Behavior: A Pilot Controlled Trial
We investigated the effects of group music intervention on aggression and self-esteem in children with highly aggressive behavior. Forty-eight children were allocated to either a music intervention group or an untreated control group. The music intervention group received 50 min of music intervention twice weekly for 15 consecutive weeks. The outcome measures were Child Behavior Checklist Aggression Problems Scale (Parents), Child Aggression Assessment Inventory (Teachers) and Rosenberg Self-esteem Scale. After 15 weeks, the music intervention group showed significant reduction of aggression and improvement of self-esteem compared with the control group. All outcome measures were significantly lower in the music intervention group than prior to treatment, while there was no change in the control group. These findings suggest that music can reduce aggressive behavior and improve self-esteem in children with highly aggressive behavior. Music intervention is an easily accessible therapy for children and as such may be an effective intervention for aggressive behavior. Further more, objective and replicable measures are required from a randomized controlled trial with a larger sample size and active comparable control
Specific Heat Study of the Magnetic Superconductor HoNi2B2C
The complex magnetic transitions and superconductivity of HoNi2B2C were
studied via the dependence of the heat capacity on temperature and in-plane
field angle. We provide an extended, comprehensive magnetic phase diagram for B
// [100] and B // [110] based on the thermodynamic measurements. Three magnetic
transitions and the superconducting transition were clearly observed. The 5.2 K
transition (T_{N}) shows a hysteresis with temperature, indicating the first
order nature of the transition at B=0 T. The 6 K transition (T_{M}), namely the
onset of the long-range ordering, displays a dramatic in-plane anisotropy:
T_{M} increases with increasing magnetic field for B // [100] while it
decreases with increasing field for B // [110]. The anomalous anisotropy in
T_{M} indicates that the transition is related to the a-axis spiral structure.
The 5.5 K transition (T^{*}) shows similar behavior to the 5.2 K transition,
i.e., a small in-plane anisotropy and scaling with Ising model. This last
transition is ascribed to the change from a^{*} dominant phase to c^{*}
dominant phase.Comment: 9 pages, 11 figure
Estimation of manganese daily intake among adults in Korea
The purpose of this study was to estimate daily intake of manganese in Korean adults. Manganese intake was estimated through the use of the database of manganese content in frequently consumed Korean foods after first conducting anthropometric measurement and a survey on dietary intake with 354 Korean adults. Average age, height, weight and body mass index were 54.6 years, 165.7 cm, 67.2 kg and 24.5 kg/m2 in males and 53.8 years, 153.7 cm, 59.1 kg and 24.9 kg/m2 in females. The daily energy intakes of subjects were 1740.1 kcal in males and 1432.6 kcal in females. Male and female subjects recorded, respectively, 5.2 mg and 4.1 mg in manganese intake indicating that the male subjects consume more manganese (p<0.001). And they posted, respectively, 3.0 mg and 2.9 mg in manganese intake per 1000 kcal of energy consumption; it turned out that there was no significant difference. Daily manganese intake of both males and females posted, respectively, 148.8% and 135.2% of the adequate intake, and 8 males and 3 females surpassed the tolerable upper intake level. It is suggested that the study for accurate determination of manganese consumption needs to be more diversified based on the database of manganese content in Korean foods
Determination of EGFR Endocytosis Kinetic by Auto-Regulatory Association of PLD1 with mu 2
Background: Upon ligand binding, cell surface signaling receptors are internalized through a process tightly regulated by endocytic proteins and adaptor protein 2 (AP2) to orchestrate them. Although the molecular identities and roles of endocytic proteins are becoming clearer, it is still unclear what determines the receptor endocytosis kinetics which is mainly regulated by the accumulation of endocytic apparatus to the activated receptors. Methodology/Principal Findings: Here we employed the kinetic analysis of endocytosis and adaptor recruitment to show that ??2, a subunit of AP2 interacts directly with phospholipase D (PLD)1, a receptor-associated signaling protein and this facilitates the membrane recruitment of AP2 and the endocytosis of epidermal growth factor receptor (EGFR). We also demonstrate that the PLD1-??2 interaction requires the binding of PLD1 with phosphatidic acid, its own product. Conclusions/Significance: These results suggest that the temporal regulation of EGFR endocytosis is achieved by auto-regulatory PLD1 which senses the receptor activation and triggers the translocation of AP2 near to the activated receptor.open3
Flashlights: More than A Dozen High-Significance Microlensing Events of Extremely Magnified Stars in Galaxies at Redshifts z=0.7-1.5
Once only accessible in nearby galaxies, we can now study individual stars
across much of the observable universe aided by galaxy-cluster gravitational
lenses. When a star, compact object, or multiple such objects in the foreground
galaxy-cluster lens become aligned, they can magnify a background individual
star, and the timescale of a magnification peak can limit its size to tens of
AU. The number and frequency of microlensing events therefore opens a window
into the population of stars and compact objects, as well as high-redshift
stars. To assemble the first statistical sample of stars in order to constrain
the initial mass function (IMF) of massive stars at redshift z=0.7-1.5, the
abundance of primordial black holes in galaxy-cluster dark matter, and the IMF
of the stars making up the intracluster light, we are carrying out a 192-orbit
program with the Hubble Space Telescope called "Flashlights," which is now
two-thirds complete owing to scheduling challenges. We use the ultrawide F200LP
and F350LP long-pass WFC3 UVIS filters and conduct two 16-orbit visits
separated by one year. Having an identical roll angle during both visits, while
difficult to schedule, yields extremely clean subtraction. Here we report the
discovery of more than a dozen bright microlensing events, including multiple
examples in the famous "Dragon Arc" discovered in the 1980s, as well as the
"Spocks" and "Warhol" arcs that have hosted already known supergiants. The
ultradeep observer-frame ultraviolet-through-optical imaging is sensitive to
hot stars, which will complement deep James Webb Space Telescope infrared
imaging. We are also acquiring Large Binocular Telescope LUCI and Keck-I
MOSFIRE near-infrared spectra of the highly magnified arcs to constrain their
recent star-formation histories
Uncovering the nutritional landscape of food
Recent progresses in data-driven analysis methods, including network-based
approaches, are revolutionizing many classical disciplines. These techniques
can also be applied to food and nutrition, which must be studied to design
healthy diets. Using nutritional information from over 1,000 raw foods, we
systematically evaluated the nutrient composition of each food in regards to
satisfying daily nutritional requirements. The nutrient balance of a food was
quantified herein as nutritional fitness, using the food's frequency of
occurrence in nutritionally adequate food combinations. Nutritional fitness
offers prioritization of recommendable foods within a global network of foods,
in which foods are connected based on the similarities of their nutrient
compositions. We identified a number of key nutrients, such as choline and
alpha-linolenic acid, whose levels in foods can critically affect the foods'
nutritional fitness. Analogously, pairs of nutrients can have the same effect.
In fact, two nutrients can impact the nutritional fitness synergistically,
although the individual nutrients alone may not. This result, involving the
tendency among nutrients to show correlations in their abundances across foods,
implies a hidden layer of complexity when exploring for foods whose balance of
nutrients within pairs holistically helps meet nutritional requirements.
Interestingly, foods with high nutritional fitness successfully maintain this
nutrient balance. This effect expands our scope to a diverse repertoire of
nutrient-nutrient correlations, integrated under a common network framework
that yields unexpected yet coherent associations between nutrients. Our
nutrient-profiling approach combined with a network-based analysis provides a
more unbiased, global view of the relationships between foods and nutrients,
and can be extended towards nutritional policies, food marketing, and
personalized nutrition.Comment: Supplementary material is available at the journal websit
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