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The GCC pivot to Asia : the security of US interests in the Arabian Gulf
textThe Gulf Cooperation Council's pivot to Asia began as a slow process of economic integration in the early 2000s but significantly accelerated after the US Shale Revolution, beginning in 2008. As US production increased and imports from foreign oil suppliers declined, many expected the relationships between the US and its GCC partners to similarly decline. The emerging markets of Asia and rising demand from China captured GCC interest. The GCC nations took steps to diversify their markets away from the US. Economic cooperation morphed into budding diplomatic and strategic relationships between the GCC and China. Meanwhile, the US, no longer as reliant on GCC energy, restructured its foreign policy toward the GCC around defense cooperation and human rights. Though US-GCC relationships remained relatively strong, the uprisings of the Arab Spring resulted in mounting US criticism of GCC human rights violations, weakening US leverage in the region. The Chinese took advantage of US-GCC tension, offering an alternative model of diplomatic engagement-- ignoring human rights. Arab populations saw the economic rise of China as an alternative diplomatic model, one that prioritized economic development without attaching political strings to bilateral relationships. Some GCC nations also viewed Chinese influence as a potential foil to US influence in the region. Despite budding local support for stronger ties with China, the Chinese are not able to displace US influence in the Gulf yet because China is unable to provide the quality or quantity of defense sales and cooperation the US provides. In the long-term, though, Chinese policies will likely present a challenge to US influence in the Gulf. The US should reexamine its policies on human rights promotion and reevaluate its strategic interests to protect the short and long term interests of the US in a region of great geostrategic importance.Middle Eastern StudiesGlobal Policy Studie
Home, Precarious Home: A Year of Housing Law Advocacy at a Saskatoon Legal Clinic
This article discusses the impacts of housing law advocacy by clinical law students at Community Legal Assistance Services for Saskatoon Inner City (CLASSIC) through an analysis of CLASSIC’s 2017 closed housing law files. Our analysis shows that law student advocacy at the Office of Residential Tenancies (Saskatchewan’s housing law tribunal) is often associated with decisions in favour of tenants. This is consistent with studies that show that full legal representation is associated with improved litigation outcomes for clients. But our analysis also demonstrates the numerous limits to individual advocacy in housing law contexts. Our study contributes to the literature about the impacts of clinical law programs through a nuanced, contextual, and ground-level discussion of the housing advocacy by clinical law students and their clients within a community legal clinic
Quantum key distribution devices: How to make them and how to break them
As more aspects of modern society depend on digital communication, we increasingly rely on infrastructure that ensures the privacy and security of this communication. Classically, this has been provided by cryptographic protocols such as public-key encryption, in which secrets called keys are exchanged between different parties to enable secure communication. The rapid development of quantum algorithms which violate the assumptions of these protocols, however, poses a security challenge to modern cryptography.
Quantum resources can also be used to strengthen cryptographic security, particularly the security of key exchange protocols. This approach, QKD, can be implemented by encoding in quantum systems such as single photons sent through free-space or a fiber. Fiber based QKD devices are already commercially available, but are fundamentally limited to distributing keys over a few hundred kilometers. To address this distance limitation, research QKD systems are being developed to exchange keys through free-space to satellites. This work considers practical challenges to building and testing both types of QKD devices.
Firstly, we consider modeling and mission analysis for airborne demonstrations of QKD to stratospheric balloons and aircraft to simulate a satellite. Based on the mission parameters available for both platforms, we found aircraft platforms were more promising for testing prototype QKD satellite systems. We developed a mission planning tool to help design the flight geometries for testing the device.
Next, we developed three new components for a QKD satellite prototype. The requirements for electro-optical devices in orbit are very different from lab environments, mandating new approaches to designing QKD devices. We developed a quad single photon detector package to meet the requirements for free-space links to low earth orbit. Moreover, we designed and built optical systems for analyzing the polarization of photons and an adaptive optics unit to increase the efficiency of collecting the encoded photons. All three devices were tested in conditions that simulated the time and loss of a satellite pass.
Finally, we demonstrated a laser damage attack on a live commercial QKD system. Our attack injected additional optical power into the sender device to modify security-critical components. Specifically, our attack damaged the PIN diodes which monitor the encoded photon number, reducing their sensitivity or completely blinding them. Our damage could compromise the entire key, and was performed during system operation while raising no alarms.
In summary, this work shows the trade-offs of testing QKD payloads on different airborne platforms, develops components for a satellite QKD payload, and demonstrates a security vulnerability in a commercial QKD system that can fully compromise the key. These results help address practical challenges to building QKD devices, improving the security of modern cryptography
A Case of Statin-Associated Autoimmune Myopathy.
A 70-year-old previously independent man developed progressive proximal leg weakness resulting in a fall at home suffering traumatic brain injury. He was prescribed a statin medication two years prior, but this was discontinued on admission to the hospital due to concern for statin myopathy. His weakness continued to progress while in acute rehabilitation, along with the development of dysphagia requiring placement of gastrostomy tube and respiratory failure requiring tracheostomy. Corticosteroids and intravenous immunoglobulin were administered without response. Nerve conduction study demonstrated no evidence of neuropathy; electromyography revealed spontaneous activity suggestive of myopathy. A muscle biopsy was performed and demonstrated myonecrosis. Serology was positive for autoantibodies to 3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMGCR), verifying our diagnosis of statin-associated autoimmune myopathy (SAM). The patient was subsequently treated with rituximab and methotrexate and demonstrated mild clinical improvement. He was eventually liberated from the ventilator. However, later in the course of treatment, he developed respiratory distress and required ventilator support. The patient was discharged to long-term acute care two months after his initial presentation and died due to ventilator-acquired pneumonia three months later. Since their introduction 30 years ago, statin medications have been widely prescribed to prevent cardiovascular diseases. Myalgias and/or myopathic symptoms are among the most recognized side effects of the medication. Statin-associated autoimmune myopathy is a very rare complication of statin use and estimated to affect two to three for every 100,000 patients treated. Clinically, the condition presents as progressive symmetric weakness, muscle enzyme elevations, necrotizing myopathy on muscle biopsy, and the presence of autoantibodies to HMGCR. These findings will often persist and even progress despite discontinuation of the statin. Very few cases of SAM have been described in the literature. Describing this rare condition and the ultimately fatal outcome of our patient, we aim to further understanding of SAM, its presentation and clinical course to promote earlier diagnosis and prompt management
Experimental quantum key distribution with source flaws
Decoy-state quantum key distribution (QKD) is a standard technique in current
quantum cryptographic implementations. Unfortunately, existing experiments have
two important drawbacks: the state preparation is assumed to be perfect without
errors and the employed security proofs do not fully consider the finite-key
effects for general attacks. These two drawbacks mean that existing experiments
are not guaranteed to be secure in practice. Here, we perform an experiment
that for the first time shows secure QKD with imperfect state preparations over
long distances and achieves rigorous finite-key security bounds for decoy-state
QKD against coherent attacks in the universally composable framework. We
quantify the source flaws experimentally and demonstrate a QKD implementation
that is tolerant to channel loss despite the source flaws. Our implementation
considers more real-world problems than most previous experiments and our
theory can be applied to general QKD systems. These features constitute a step
towards secure QKD with imperfect devices.Comment: 12 pages, 4 figures, updated experiment and theor
YOUNG PATIENTS INFECTED WITH HUMAN IMMUNODEFICIENCY VIRUS HAVE ELEVATED CONCENTRATIONS OF ASYMMETRIC DIMETHYLARGININE AND CORONARY ARTERY CALCIFICATION
Creation of backdoors in quantum communications via laser damage
Practical quantum communication (QC) protocols are assumed to be secure
provided implemented devices are properly characterized and all known side
channels are closed. We show that this is not always true. We demonstrate a
laser-damage attack capable of modifying device behaviour on-demand. We test it
on two practical QC systems for key distribution and coin-tossing, and show
that newly created deviations lead to side channels. This reveals that laser
damage is a potential security risk to existing QC systems, and necessitates
their testing to guarantee security.Comment: Changed the title to match the journal version. 9 pages, 5 figure
Prevalence and WGS-based characteristics of Staphylococcus aureus in the nasal mucosa and pastern of horses with equine pastern dermatitis.
BACKGROUND
Many contributing factors are involved in the development of equine pastern dermatitis (EPD). Among the most frequently suspected is Staphylococcus aureus, known for its pathogenic potential in skin and soft tissue infections. We therefore investigated the association between S. aureus carriage and EPD.
RESULTS
One hundred five EPD-affected horses and 95 unaffected controls were examined for the presence of methicillin-resistant and -susceptible Staphylococcus aureus (MRSA and MSSA) on the pastern skin and in the nostrils. S. aureus isolates were cultivated from swab samples on selective MSSA and MRSA chromogenic agar and identified using MALDI-TOF MS. Isolates were analysed by Illumina whole genome sequencing for genetic relatedness (cgMLST, spa typing), and for the presence of antimicrobial resistance and virulence determinants. A markedly higher proportion of samples from EPD-affected horses proved positive for S. aureus, both from the pastern (59.0 % vs. 6.3 % in unaffected horses; P<0.001), and from the nose (59.0 % vs. 8.4 %; P<0.001). Isolates belonged to 20 sequence types (ST) with lineages ST15-t084 (spa) (18 %), ST1-t127 (13 %), and ST1-t1508 (12 %) being predominant. Eight S. aureus were MRSA ST398-t011 and ST6239-t1456, and contained the staphylococcal cassette chromosome SCCmecIVa. Antimicrobial resistance genes were almost equally frequent in pastern and in nasal samples, whereas some virulence factors such as the beta-hemolysin, ESAT-6 secretion system, and some enterotoxins were more abundant in isolates from pastern samples, possibly enhancing their pathogenic potential.
CONCLUSIONS
The markedly higher prevalence of S. aureus containing specific virulence factors in affected skin suggests their contribution in the development and course of EPD
Noise bias in weak lensing shape measurements
Weak lensing experiments are a powerful probe of cosmology through their
measurement of the mass distribution of the universe. A challenge for this
technique is to control systematic errors that occur when measuring the shapes
of distant galaxies. In this paper we investigate noise bias, a systematic
error that arises from second order noise terms in the shape measurement
process. We first derive analytical expressions for the bias of general Maximum
Likelihood Estimators (MLEs) in the presence of additive noise. We then find
analytical expressions for a simplified toy model in which galaxies are modeled
and fitted with a Gaussian with its size as a single free parameter. Even for
this very simple case we find a significant effect. We also extend our analysis
to a more realistic 6-parameter elliptical Gaussian model. We find that the
noise bias is generically of the order of the inverse-squared signal-to-noise
ratio (SNR) of the galaxies and is thus of the order of a percent for galaxies
of SNR of 10, i.e. comparable to the weak lensing shear signal. This is nearly
two orders of magnitude greater than the systematics requirements for future
all-sky weak lensing surveys. We discuss possible ways to circumvent this
effect, including a calibration method using simulations discussed in an
associated paper.Comment: 8 pages, 3 figures, submitted to MNRA
Opening opportunities for high-resolution isotope analysis - Quantification of δ15NNO3 and δ18ONO3 in diffusive equilibrium in thin–film passive samplers
The fate of nitrate transported across groundwater-surface water interfaces has been intensively studied in recent decades. The interfaces between aquifers and rivers or lakes have been identified as biogeochemical hotspots with steep redox gradients. However, a detailed understanding of the spatial heterogeneity and potential temporal variability of these hotspots, and the consequences for nitrogen processing, is still hindered by a paucity of adequate measurement techniques. A novel methodology is presented here, using Diffusive Equilibrium in Thin-film (DET) gels as high-spatial-resolution passive-samplers of δ15NNO3 and δ18ONO3 to investigate nitrogen cycling. Fractionation of δ15NNO3 and δ18ONO3 during diffusion of nitrate through the DET gel was determined using varying equilibrium times and nitrate concentrations. This demonstrated that nitrate isotopes of δ15NNO3 and δ18ONO3 do not fractionate when sampled with a DET gel. δ15NNO3 values from the DET gels ranged between 2.3 ± 0.2 and 2.7 ± 0.3‰ for a NO3– stock solution value of 2.7 ± 0.4‰, and δ18ONO3 values ranged between 18.3 ± 1.0 and 21.5 ± 0.8‰ for a NO3– stock solution of 19.7 ± 0.9‰. Nitrate recovery and isotope values were independent of equilibrium time and nitrate concentration. Additionally, an in situ study showed that nitrate concentration and isotopes provide unique, high-resolution data that enable improved understanding of nitrogen cycling in freshwater sediments
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