4,895 research outputs found
Applying Marxism to critical terrorism studies: analysis through a historical materialist lens
A precarious peace? The threat of paramilitary violence to the peace process in Colombia
This article provides an investigation into claims that paramilitary violence in Colombia can pose a threat to the peace agreement signed in 2016 between the Colombian government and the FARC rebels. These claims highlight the capacity for paramilitary groups to âspoilâ the peace deal. Hitherto, however, there is a lack of scholarly research to investigate the potential of paramilitary spoiling. Firstly, this article highlights the flaws in the governmentâs perspective that paramilitarism no longer exists in Colombia. Instead, the government argues that Colombia is plagued by criminal bands (known as BACRIMs). Secondly, through fieldwork interviews and questionnaires conducted in FARC demobilisation camps, together with descriptive data analysed through a uniquely coded dataset on violence in western Colombia, this article supports claims that successor paramilitary groups represent a key spoiler threat to the current government-FARC peace process. On the one hand, the paramilitaries can represent a direct spoiler threat by, for instance, violently targeting demobilising FARC guerrillas. On the other hand, successor paramilitary groups represent a key indirect spoiler threat, as paramilitary violence is exacerbating the root causes of the conflict that the peace deal seeks to address, with negative implications for the prospects for peace
Simulating Dispersion in the Evening-Transition Boundary Layer
This is the author accepted manuscript. The final version is available from Springer Verlag via the DOI in this recordWe investigate dispersion in the evening-transition boundary layer using large-eddy simulation (LES). In the LES, a particle model traces pollutant paths using a combination of the resolved flow velocities and a random displacement model to represent subgrid-scale motions. The LES is forced with both a sudden switch-off of the surface heat flux and also a more gradual observed evolution. The LES shows âloftingâ of plumes from near-surface releases in the pre-transition convective boundary layer; it also shows the subsequent âtrappingâ of releases in the post-transition near-surface stable boundary layer and residual layer above. Given the paucity of observations for pollution dispersion in evening transitions, the LES proves a useful reference. We then use the LES to test and improve a one-dimensional Lagrangian Stochastic Model (LSM) such as is often used in practical dispersion studies. The LSM used here includes both time-varying and skewed turbulence statistics. It is forced with the vertical velocity variance, skewness and dissipation from the LES for particle releases at various heights and times in the evening transition. The LSM plume spreads are significantly larger than those from the LES in the post-transition stable boundary-layer trapping regime. The forcing from the LES was thus insufficient to constrain the plume evolution, and inclusion of the significant stratification effects was required. In the so-called modified LSM, a correction to the vertical velocity variance was included to represent the effect of stable stratification and the consequent presence of wave-like motions. The modified LSM shows improved trapping of particles in the post-transition stable boundary layer
Prevalence of mixed genotype hepatitis C virus infections in the UK as determined by genotypeâspecific PCR and deep sequencing
The incidence of mixed genotype hepatitis C virus infections in the UK is largely unknown. As the efficacy of direct acting antivirals is variable across different genotypes, treatment regimens are tailored to the infecting genotype, which may pose issues for the treatment of underlying genotypes within undiagnosed mixed genotype HCV infections. There is therefore a need to accurately diagnose mixed genotype infections prior to treatment. PCR-based diagnostic tools were developed to screen for the occurrence of mixed genotype infections caused by the most common UK genotypes, 1a and 3, in a cohort of 506 individuals diagnosed with either of these genotypes. The overall prevalence rate of mixed infection was 3.8% however this rate was unevenly distributed, with 6.7% of individuals diagnosed with genotype 3 harbouring genotype 1a strains and only 0.8% of samples from genotype 1a patients harbouring genotype 3 (p<0.05). Mixed infection samples consisted of a major and a minor genotype, with the latter constituting less than 21% of the total viral load and, in 67% of cases, less than 1% of the viral load. Analysis of a subset of the cohort by Illumina PCR-next generation sequencing resulted in a much greater incidence rate than obtained by PCR. This may have occurred due to the non-quantitative nature of the technique and despite the designation of false positive thresholds based on negative controls
Influence of 4-vinylbenzylation on the rheological and swelling properties of photo activated collagen hydrogels
Covalent functionalisation of collagen has been shown to be a promising strategy to adjust the mechanical properties of highly swollen collagen hydrogels. At the same time, secondary interactions between for example, amino acidic terminations or introduced functional groups also play an important role and are often challenging to predict and control. To explore this challenge, 4-vinylbenzyl chloride (4VBC) and methacrylic anhydride (MA) were reacted with type I collagen, and the swelling and rheological properties of resulting photo-activated hydrogel systems investigated. 4VBC-based hydrogels showed significantly increased swelling ratio, in light of the lower degree of collagen functionalisation, with respect to methacrylated collagen networks, whilst rheological storage moduli were found to be comparable between the two systems. To explore the role of benzyl groups in the mechanical properties of the 4VBC-based collagen system, model chemical force microscopy (CFM) was carried out in aqueous environment with an aromatised probe against an aromatised gold-coated glass slide. A marked increase in adhesion force (F: 0.11±0.01 nN) was measured between aromatised samples, compared to the adhesion force observed between the non-modified probe and a glass substrate (F: 2.64±1.82 nN). These results suggest the formation of additional and reversible Ï-Ï stacking interactions in aromatic 4VBC-based networks and explain the remarkable rheological properties of this system in comparison to MA-based hydrogels
Response to âComment on âSeagrass Viviparous Propagules as a Potential Long-Distance Dispersal Mechanismâ by A. C. G. Thomson et alâ
Stability, resolution, and ultra-low wear amplitude modulation atomic force microscopy of DNA: Small amplitude small set-point imaging
A way to operate fundamental mode amplitude modulation atomic force microscopy is introduced which optimizes stability and resolution for a given tip size and shows negligible tip wear over extended time periods (âŒ24 h). In small amplitude small set-point (SASS) imaging, the cantilever oscillates with sub-nanometer amplitudes in the proximity of the sample, without the requirement of using large drive forces, as the dynamics smoothly lead the tip to the surface through the water layer. SASS is demonstrated on single molecules of double-stranded DNA in ambient conditions where sharp silicon tips (R ⌠2-5 nm) can resolve the right-handed double helix
Reliable consultant level data from an Acute Medical Unit: a powerful tool for improvement
The development of a novel database interrogating the patient management system in the Acute Medical Unit at Forth Valley Royal Hospital, Scotland, has allowed, for the first time, acquisition of reliable individual consultant-level process and outcome data over a 2-year period. These data have a number of uses, including understanding the level of variation between consultant physicians in AMU across key indicators, such as direct discharge percentage (67.5â44.3%), and readmission percentage (4.0â6.8%). Looking at overnight admissions only effectively excluded case mix as a confounder to identify variation in 30-day mortality (0â2.8%). This has allowed benchmarking, and exploring of relationships between volume of work, physician experience, and patient outcomes. For example, no significant relationship was seen between direct discharge percentage and readmission percentage. Furthermore it is extremely useful for individual clinician appraisal and governance. Finally it has practical uses when designing consultant rotas in order to minimise system variation. A key consideration throughout this work has been clear provenance and local clinical ownership of these data, unlike centrally generated data that may not accurately reflect Acute Medical Unit activity
Comment on: âCorrections to the Mathematical Formulation of a Backwards Lagrangian Particle Dispersion Modelâ by Gibson and Sailor (2012: Boundary-Layer Meteorology 145, 399â406)
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