On the Complexity of an Unregulated Traffic Crossing

The steady development of motor vehicle technology will enable cars of the near future to assume an ever increasing role in the decision making and control of the vehicle itself. In the foreseeable future, cars will have the ability to communicate with one another in order to better coordinate their motion. This motivates a number of interesting algorithmic problems. One of the most challenging aspects of traffic coordination involves traffic intersections. In this paper we consider two formulations of a simple and fundamental geometric optimization problem involving coordinating the motion of vehicles through an intersection. We are given a set of $n$ vehicles in the plane, each modeled as a unit length line segment that moves monotonically, either horizontally or vertically, subject to a maximum speed limit. Each vehicle is described by a start and goal position and a start time and deadline. The question is whether, subject to the speed limit, there exists a collision-free motion plan so that each vehicle travels from its start position to its goal position prior to its deadline. We present three results. We begin by showing that this problem is NP-complete with a reduction from 3-SAT. Second, we consider a constrained version in which cars traveling horizontally can alter their speeds while cars traveling vertically cannot. We present a simple algorithm that solves this problem in $O(n \log n)$ time. Finally, we provide a solution to the discrete version of the problem and prove its asymptotic optimality in terms of the maximum delay of a vehicle

African Challenges to the International Criminal Court: An Example of Populism?

Recent global efforts of the United States and England to withdraw from international institutions, along with recent challenges to human rights courts from Poland and Hungary, have been described as part of a growing global populist backlash against the liberal international order. Several scholars have even identified the recent threat of mass withdrawal of African states from the International Criminal Court (ICC) as part of this global populist backlash. Are the African challenges to the ICC part of a global populist movement developing in Africa? More fundamentally, how are the African challenges to the ICC examples of populism, if at all? In this paper, I show that, while there is considerable overlap between the strategies used by particular African leaders to challenge the ICC and those typically considered populist, as well as a discernible thin populist ideology to sustain them, there is insufficient evidence of a larger anti-ICC populist movement in Africa. Although Africa is not as united against the ICC as the populist narrative suggests, the recent challenges to the Court from Africa pose a significant challenge to the Court, as the institution is still in the early stages of building its legitimacy

The academic radiography workforce: Age profile, succession planning and academic development.

This is the author accepted manuscript. The final version is available from Elsevier via the DOI in this record.Introduction: Academia is one area of practice in which radiographers can specialise; they compile approximately 2% of the total radiography profession in the UK, but are highly influential and essential for the education and development of the workforce in addition to undertaking research. However, the academic environment is very different to clinical practice and a period of transition is required. Methods: Data were collated to explore the age and retirement profile of the academic radiography workforce in the UK; to understand the research time allocated to this workforce; the time required to develop a clinical radiographer into an academic and the mentorship and succession planning provisions nationally. An online UK wide survey was conducted and sent to all 24 Universities delivering radiography education within the UK. Results: Eighteen out of 24 Universities in the UK responded to the survey. Approximately 30% of radiography academics are due to retire over the next ten years, with over 25% of radiographers who currently hold a doctorate qualification included within this figure. Those entering academia have notably lower qualifications as a group than those who are due to retire. Developing clinical radiographers into academics was thought to take 1-3 years on average, or longer if they are required to undertake research. Conclusion: There is vulnerability in the academic radiography workforce. Higher education institutions need to invest in developing the academic workforce to maintain research and educational expertise, which is underpinned by master’s and doctorate level qualifications

Public experiences of mass casualty decontamination

In this article, we analyze feedback from simulated casualties who took part in field exercises involving mass decontamination, to gain an understanding of how responder communication can affect people’s experiences of and compliance with decontamination. We analyzed questionnaire data gathered from 402 volunteers using the framework approach, to provide an insight into the public’s experiences of decontamination and how these experiences are shaped by the actions of emergency responders. Factors that affected casualties’ experiences of the econtamination process included the need for greater practical information and better communication from responders, and the need for privacy. Results support previous findings from small-scale incidents that involved decontamination in showing that participants wanted better communication from responders during the process of decontamination, including more practical information, and that the failure of responders to communicate effectively with members of the public led to anxiety about the decontamination process. The similarity between the findings from the exercises described in this article and previous research into real incidents involving decontamination suggests that field exercises provide a useful way to examine the effect of responder communication strategies on the public’s experiences of decontamination. Future exercises should examine in more detail the effect of various communication strategies on the public’s experiences of decontamination. This will facilitate the development of evidence-based communication strategies intended to reduce anxiety about decontamination and increase compliance among members of the public during real-life incidents that involve mass decontamination

Microbiota is essential for social development in the mouse

No abstract available

Hydrological assessment and monitoring of wetlands

The physical and chemical characteristics which favour wetland plant communities, primarily high soil water levels and anaerobic soil chemistry, are related directly to the hydrology/hydrogeology of the wetland and often its surrounding catchment. Appreciation and successful management of a wetland therefore almost always requires an understanding of its hydrological functioning, including the influences on hydrological functioning which often lie beyond the designated boundary of the sit

Effect of marker choice and thermal cycling protocol on zooplankton DNA metabarcoding studies

DNA metabarcoding is a promising approach for rapidly surveying biodiversity and is likely to become an important tool for measuring ecosystem responses to environmental change. Metabarcoding markers need sufficient taxonomic coverage to detect groups of interest, sufficient sequence divergence to resolve species, and will ideally indicate relative abundance of taxa present. We characterized zooplankton assemblages with three different metabarcoding markers (nuclear 18S rDNA, mitochondrial COI, and mitochondrial 16S rDNA) to compare their performance in terms of taxonomic coverage, taxonomic resolution, and correspondence between morphology- and DNA-based identification. COI amplicons sequenced on separate runs showed that operational taxonomic units representing >0.1% of reads per sample were highly reproducible, although slightly more taxa were detected using a lower annealing temperature. Mitochondrial COI and nuclear 18S showed similar taxonomic coverage across zooplankton phyla. However, mitochondrial COI resolved up to threefold more taxa to species compared to 18S. All markers revealed similar patterns of beta-diversity, although different taxa were identified as the greatest contributors to these patterns for 18S. For calanoid copepod families, all markers displayed a positive relationship between biomass and sequence reads, although the relationship was typically strongest for 18S. The use of COI for metabarcoding has been questioned due to lack of conserved primer-binding sites. However, our results show the taxonomic coverage and resolution provided by degenerate COI primers, combined with a comparatively well-developed reference sequence database, make them valuable metabarcoding markers for biodiversity assessment

Deep 230-470 MHz VLA observations of the mini-halo in the Perseus cluster

© 2017 The Authors. We present a low-frequency view of the Perseus cluster with new observations from the Karl G. Jansky Very Large Array (JVLA) at 230-470 MHz. The data reveal a multitude of new structures associated with the mini-halo. The mini-halo seems to be influenced both by the AGN activity and the sloshing motion of the cool core cluster's gas. In addition, it has a filamentary structure similar to that seen in radio relics found in merging clusters. We present a detailed description of the data reduction and imaging process of the dataset. The depth and resolution of the observations allow us to conduct for the first time a detailed comparison of the mini-halo structure with the X-ray structure as seen in the Chandra X-ray images. The resulting image very clearly shows that the mini-halo emission is mostly contained behind the western cold front, similar to that predicted by simulations of gas sloshing in galaxy clusters, but fainter emission is also seen beyond, as if particles are leaking out. However, due to the proximity of the Perseus cluster, as well as the quality of the data at low radio frequencies and at X-ray wavelengths, we also find evidence of fine structure. This structure includes several radial radio filaments extending in different directions, a concave radio structure associated with the southern X-ray bay and sharp radio edges that correlate with X-ray edges. Minihaloes are therefore not simply diffuse, uniform radio sources, but rather have a rich variety of complex structures. These results illustrate the high-quality images that can be obtained with the new JVLA at low radio frequencies, as well as the necessity to obtain deeper, higher fidelity radio images of mini-haloes in clusters to further understand their origin

Frontal sinus mucocele with orbital extension drained via a combined upper lid skin crease and endoscopic approach.

This case report discusses the ophthalmic complications of frontal sinus mucoceles and describes the favorable long-term surgical outcomes of a combined endoscopic and upper-lid skin crease drainage approach carried out jointly with otorhinolaryngology. A 47-year-old single mother presented to eye casualty with markedly swollen eyelids and visual acuity of 6/6 in the left eye, no perception of light in the right. Ophthalmic examination revealed right-sided hypoglobus and proptosis with exposure keratopathy inferiorly. There was complete ophthalmoplegia in the right eye and a hemorrhagic optic disc visible on fundoscopy. CT orbit with contrast confirmed a diagnosis of giant frontal mucocele with orbital extension. The patient underwent mucocele drainage via a modified anterior orbitotomy approach and FESS (Functional Endoscopic Sinus Surgery) drainage performed jointly with otorhinolaryngology. Two weeks post-operatively her proptosis was resolving and by three months she had regained full extraocular motility. As expected, vision was not restored in the right eye. At one year, the patient's upper lid skin crease scar was completely buried in the eyelid's natural contour, and repeat CT scanning confirmed no re-stenosis or mucocele recurrence. This case demonstrates, that a multidisciplinary approach to far-lateral frontal sinus mucoceles with orbital extension and ophthalmic complications which combines an upper lid skin crease incision with FESS drainage, allows adequate access to the frontal sinus while preserving cosmesis