Classical r-matrices via semidualisation

We study the interplay between double cross sum decompositions of a given Lie algebra and classical r-matrices for its semidual. For a class of Lie algebras which can be obtained by a process of generalised complexification we derive an expression for classical r-matrices of the semidual Lie bialgebra in terms of the data which determines the decomposition of the original Lie algebra. Applied to the local isometry Lie algebras arising in three-dimensional gravity, decomposition and semidualisation yields the main class of non-trivial r-matrices for the Euclidean and Poincare group in three dimensions. In addition, the construction links the r-matrices with the Bianchi classification of three dimensional real Lie algebras.Comment: 21 pages, 1 figure, typos correcte

Classical r-matrices for the generalised Chern-Simons formulation of 3d gravity

We study the conditions for classical r-matrices to be compatible with the generalised Chern-Simons action for 3d gravity. Compatibility means solving the classical Yang-Baxter equations with a prescribed symmetric part for each of the real Lie algebras and bilinear pairings arising in the generalised Chern-Simons action. We give a new construction of r-matrices via a generalised complexification and derive a non-linear set of matrix equations determining the most general compatible r-matrix. We exhibit new families of solutions and show that they contain known solutions for special parameter valuesComment: 20 pages, minor corrections and comments added in v

Kitaev lattice model for bicrossproduct Hopf algebras and tensor network representation

Kitaev's lattice models are usually defined as representations of the Drinfeld quantum double. We propose a new version based on Majid's bicrossproduct quantum group. Given a Hopf algebra $H$, we show that a triangulated oriented surface defines a representation of the bicrossproduct quantum group $H^{\text{cop}}\blacktriangleright\!\!\!\triangleleft H$. Even though the bicrossproduct has a more complicated and entangled coproduct, the construction of this new model is relatively natural as it relies on the use of the covariant Hopf algebra actions. We obtain an exactly solvable Hamiltonian for the model and provide a definition of the ground state in terms of a tensor network representation.Comment: 34 page

Adaptation Strategies of Smallholder Farmers to Climate Change and Variability: Evidence from Northern Ghana

Farmers have been modifying their practices in order to deal with climate change and variability. Even though such practices have been documented in other parts of Africa, information on Ghana and particularly northern Ghana is scanty. This study examines the adaptation strategies of smallholder farmers to climate change and variability in northern Ghana. The paper is based on primary data collected through a household survey, community focus group discussions and key informant interviews in order to identify the adaptation responses of smallholder farmers in northern Ghana to climate change and variability. Several indigenous climate-related practices and technologies categorised into four strategies were identified. In addition, climate related technologies introduced by research, also categorised into four strategies, and were identified as being used by smallholder farmers in northern Ghana. The empirical results of the Friedman test indicates that timing of the onset of the rainy season which informed planting, and soil and plant health related strategies are the most important climate related strategies used by smallholder farmers in securing yield. The policy implication is that practical, timely and reliable information on the onset of the rainy season as well as region specific soil and plant health technologies should be generated and made available to smallholder farmers in northern Ghana to minimise the adverse impacts of climate change

Application of Livelihood Vulnerability Index in Assessing Vulnerability to Climate Change and Variability in Northern Ghana

Climate change is impacting on climate dependent activities such as agriculture in Africa and Ghana. The extent of the impact of climate change in agriculture depends on the level of vulnerability or exposure of farmers to these impacts. This study estimates the level of vulnerability of smallholder farmers to climate change and variability in northern Ghana using the Livelihood Vulnerability Index highlighting access to, and utilization of water resources. The approach estimates vulnerabilities in terms of exposure, sensitivity and adaptive capacity. The data is based on a survey of 320 farm households, complemented with secondary data on rainfall and temperature. Results of the study shows that Northern Region is the most exposed region to climate change and variability. Upper West Region is the most sensitive to climate change and variability especially with regards to water stress; and the Upper East Region has the least adaptive capacity. Northern Region is the most vulnerable in terms of the overall livelihood vulnerability index, followed by the Upper East and Upper West regions. Key Words: Livelihood, Vulnerability, Climate change, Climate variability, Northern Ghan

Comparative analysis of the socio-economic characteristics of Delta and Non-Delta spaces of Ghana: An input-output approach

This paper provides insights into the current socioeconomic and biophysical state of the Volta Delta, Ghana. We employed non-survey methods, notably the Flegg Location Quotient (FLQ) method of regionalization and construction of tables to develop environmentally extended input-output (IO) model for comparing the economic characteristics of the Volta Delta and the rest of the country. The main sources of data for doing the regionalization were District Analytical Reports. Results from the study indicate that the agricultural sector, trade and transport activities are much predominant in the delta than in the non-delta region. However, employment in services of public administration, financial and insurance, construction and crop production is higher in the non-delta than in the delta region. From a gendered perspective, the embodied work of women in the delta is high in services and manufacturing sectors, but less predominant in agriculture and fishing (compared to the males’ participation). Overall, the delta is found to be a net importer (embodied in goods and services from other regions, higher than in exports) of all the economic metrics used in the study, including agricultural land use, employment, energy and CO2 emissions.Keywords: Economic activities; Volta delta; Non-delta; Land use; Employment; Sector productions; Ghan

Preparing for future outbreaks in Ghana: An overview of current COVID-19, monkeypox, and Marburg disease outbreaks

Amidst the ongoing COVID-19 pandemic, Ghana is currently grappling with simultaneous outbreaks of Marburg virus disease and human monkeypox virus. The coexistence of these outbreaks emphasizes the imperative for a collaborative and global approach to enhance surveillance and expedite case detection. While Ghana has made efforts to respond to these outbreaks, this paper outlines the lessons learned and proposes recommendations in this regard. It is crucial to intensify response efforts at the local, regional, and national levels to effectively contain the spread of these infectious diseases. Therefore, this paper suggests prioritizing the following recommendations as crucial for assisting Ghana in adequately preparing for future outbreaks and safeguarding global public health: strengthening surveillance system through digitization, rapid and effective response; risk communication and community engagement; healthcare system readiness; and research and collaboration. Also, prioritizing building healthy public policies and developing personal skills of health personnel across the country is key for future outbreak response

Macrophage susceptibility to infection by Ghanaian Mycobacterium tuberculosis complex lineages 4 and 5 varies with self-reported ethnicity

BackgroundThe epidemiology of Mycobacterium tuberculosis complex (MTBC) lineage 5 (L5) infections in Ghana revealed a significantly increased prevalence in Ewes compared to other self-reported ethnic groups. In that context, we sought to investigate the early phase of tuberculosis (TB) infection using ex vivo infection of macrophages derived from the blood of Ewe and Akan ethnic group volunteers with MTBC L4 and L5 strains.MethodsThe study participants consisted of 16 controls, among which self-reported Akan and Ewe ethnicity was equally represented, as well as 20 cured TB cases consisting of 11 Akans and 9 Ewes. Peripheral blood mononuclear cells were isolated from both healthy controls and cured TB cases. CD14+ monocytes were isolated and differentiated into monocyte-derived macrophages (MDMs) before infection with L4 or L5 endemic strains. The bacterial load was assessed after 2 hours (uptake) as well as 3 and 7 days post-infection.ResultsWe observed a higher capacity of MDMs from Ewes to phagocytose L4 strains (p < 0.001), translating into a higher bacillary load on day 7 (p < 0.001) compared to L5, despite the higher replication rate of L5 in Ewe MDMs (fold change: 1.4 vs. 1.2, p = 0.03) among the controls. On the contrary, within macrophages from Akans, we observed a significantly higher phagocytic uptake of L5 (p < 0.001) compared to L4, also translating into a higher load on day 7 (p = 0.04). However, the replication rate of L4 in Akan MDMs was higher than that of L5 (fold change: L4 = 1.2, L4 = 1.1, p = 0.04). Although there was no significant difference in the uptake of L4 and L5 among cured TB cases, there was a higher bacterial load of both L4 (p = 0.02) and L5 (p = 0.02) on day 7 in Ewe MDMs.ConclusionOur results suggest that host ethnicity (driven by host genetic diversity), MTBC genetic diversity, and individual TB infection history are all acting together to modulate the outcome of macrophage infections by MTBC

Antimicrobial resistance among migrants in Europe: a systematic review and meta-analysis

BACKGROUND: Rates of antimicrobial resistance (AMR) are rising globally and there is concern that increased migration is contributing to the burden of antibiotic resistance in Europe. However, the effect of migration on the burden of AMR in Europe has not yet been comprehensively examined. Therefore, we did a systematic review and meta-analysis to identify and synthesise data for AMR carriage or infection in migrants to Europe to examine differences in patterns of AMR across migrant groups and in different settings. METHODS: For this systematic review and meta-analysis, we searched MEDLINE, Embase, PubMed, and Scopus with no language restrictions from Jan 1, 2000, to Jan 18, 2017, for primary data from observational studies reporting antibacterial resistance in common bacterial pathogens among migrants to 21 European Union-15 and European Economic Area countries. To be eligible for inclusion, studies had to report data on carriage or infection with laboratory-confirmed antibiotic-resistant organisms in migrant populations. We extracted data from eligible studies and assessed quality using piloted, standardised forms. We did not examine drug resistance in tuberculosis and excluded articles solely reporting on this parameter. We also excluded articles in which migrant status was determined by ethnicity, country of birth of participants' parents, or was not defined, and articles in which data were not disaggregated by migrant status. Outcomes were carriage of or infection with antibiotic-resistant organisms. We used random-effects models to calculate the pooled prevalence of each outcome. The study protocol is registered with PROSPERO, number CRD42016043681. FINDINGS: We identified 2274 articles, of which 23 observational studies reporting on antibiotic resistance in 2319 migrants were included. The pooled prevalence of any AMR carriage or AMR infection in migrants was 25·4% (95% CI 19·1-31·8; I2 =98%), including meticillin-resistant Staphylococcus aureus (7·8%, 4·8-10·7; I2 =92%) and antibiotic-resistant Gram-negative bacteria (27·2%, 17·6-36·8; I2 =94%). The pooled prevalence of any AMR carriage or infection was higher in refugees and asylum seekers (33·0%, 18·3-47·6; I2 =98%) than in other migrant groups (6·6%, 1·8-11·3; I2 =92%). The pooled prevalence of antibiotic-resistant organisms was slightly higher in high-migrant community settings (33·1%, 11·1-55·1; I2 =96%) than in migrants in hospitals (24·3%, 16·1-32·6; I2 =98%). We did not find evidence of high rates of transmission of AMR from migrant to host populations. INTERPRETATION: Migrants are exposed to conditions favouring the emergence of drug resistance during transit and in host countries in Europe. Increased antibiotic resistance among refugees and asylum seekers and in high-migrant community settings (such as refugee camps and detention facilities) highlights the need for improved living conditions, access to health care, and initiatives to facilitate detection of and appropriate high-quality treatment for antibiotic-resistant infections during transit and in host countries. Protocols for the prevention and control of infection and for antibiotic surveillance need to be integrated in all aspects of health care, which should be accessible for all migrant groups, and should target determinants of AMR before, during, and after migration. FUNDING: UK National Institute for Health Research Imperial Biomedical Research Centre, Imperial College Healthcare Charity, the Wellcome Trust, and UK National Institute for Health Research Health Protection Research Unit in Healthcare-associated Infections and Antimictobial Resistance at Imperial College London