Strongly correlated fermions on a kagome lattice

We study a model of strongly correlated spinless fermions on a kagome lattice at 1/3 filling, with interactions described by an extended Hubbard Hamiltonian. An effective Hamiltonian in the desired strong correlation regime is derived, from which the spectral functions are calculated by means of exact diagonalization techniques. We present our numerical results with a view to discussion of possible signatures of confinement/deconfinement of fractional charges.Comment: 10 pages, 10 figure

GdI_2: A New Ferromagnetic Excitonic Solid?

The two-dimensional, colossal magnetoresistive system GdI_2 develops an unusual metallic state below its ferromagnetic transition and becomes insulating at low temperatures. It is argued that this geometrically frustrated, correlated poor metal is a possible candidate for a ferromagnetic excitonic liquid. The renormalized Fermi surface supports a further breaking of symmetry to a charge ordered, excitonic solid ground state at lower temperatures via order by disorder mechanism. Several experimental predictions are made to investigate this unique orbitally correlated ground state.Comment: 4 pages, 4 figures, changed Fig. 1 with extended energy scale, added text and references, author list shortene

Draft Genome Sequence of Dietzia sp. Strain UCD-THP (Phylum Actinobacteria).

Here, we present the draft genome sequence of an actinobacterium, Dietzia sp. strain UCD-THP, isolated from a residential toilet handle. The assembly contains 3,915,613 bp. The genome sequences of only two other Dietzia species have been published, those of Dietzia alimentaria and Dietzia cinnamea

On confined fractional charges: a simple model

We address the question whether features known from quantum chromodynamics (QCD) can possibly also show up in solid-state physics. It is shown that spinless fermions of charge $e$ on a checkerboard lattice with nearest-neighbor repulsion provide for a simple model of confined fractional charges. After defining a proper vacuum the system supports excitations with charges $\pm e/2$ attached to the ends of strings. There is a constant confining force acting between the fractional charges. It results from a reduction of vacuum fluctuations and a polarization of the vacuum in the vicinity of the connecting strings.Comment: 5 pages, 3 figure

The liquid politics of an urban age

In fragile social and economic societies, water governance systems have rarely managed to meet everyone’s needs, but rather misrecognised the demand of those excluded from decision-making structures. Across regions, underlying socio-political issues have often remained unaddressed on the basis that water scarcity is primarily caused by geo-climatic conditions. Exclusionary governance is one central driver to migratory patterns along with instabilities in political regimes. It is reflected in poor service provision and tends to perpetuate injustices. Several commitments of the New Urban Agenda (NUA) set objectives of universal and equitable water provision through multi-stakeholder involvement in urban planning processes. It thereby demonstrates efforts deployed towards ‘good governance’ for transparent, accountable and participatory decision-making. However, several studies have pointed out the questionable role of citizens in NUA. Building on their argument, the present article reflects on exclusionary patterns that the NUA aims to tackle and the mechanisms it proposes to achieve this. This article aims to highlight how power relations in water governance produce and reproduce exclusion in access, such as through population movements. It questions how NUA envisions water governance structures based on collaboration between multiple stakeholders in different contexts, and highlights the need to scrutinise the people-centric language adopted in its commitments. With references to water politics from Latin America and the Middle East and North Africa (MENA) region, it adopts a political ecology approach looking at questions of inclusivity for marginalised groups and discusses approaches for the active involvement of these people in water governance models

Semiclassical ordering in the large-N pyrochlore antiferromagnet

We study the semiclassical limit of the $Sp(N)$ generalization of the pyrochlore lattice Heisenberg antiferromagnet by expanding about the $N \to \infty$ saddlepoint in powers of a generalized inverse spin. To leading order, we write down an effective Hamiltonian as a series in loops on the lattice. Using this as a formula for calculating the energy of any classical ground state, we perform Monte-Carlo simulations and find a unique collinear ground state. This state is not a ground state of linear spin-wave theory, and can therefore not be a physical (N=1) semiclassical ground state.Comment: 4 pages, 4 eps figures; published versio

Designing stakeholder consultations for institutional change: a case study from Ghana’s sanitation sector

This article evaluates the stakeholder consultation process that was undertaken to support decision-making for the new sanitation authority to be established in Ghana. This initiative of creating a specialized authority – currently referred to as the National Sanitation Authority (NSA) – emerges from the need to restructure the sector in Ghana, like in many other countries worldwide. From the learning of this study we seek to inform research and practice around the design of stakeholder consultation methods in institutional restructuration contexts. The consultation process gathered views on different aspects of the NSA, including its functions, the administrative level(s) at which it should operate, and its financing. A stakeholder analysis, a series of workshops, and key informant interviews were conducted. A tool was developed to track representativeness of participants involved in the process. Principles of stakeholder engagement developed by the Organisation for Economic Cooperation and Development informed the methodology. This consultation process highlighted the challenges of undertaking sector restructuration where responsibilities are shared between many entities, and with varying levels of interest in the planned reforms. Divergent opinions emerged on the proposed functions of the NSA, some of which represent direct conflicts of interest: for example, setting regulations, developing infrastructure, and financing. Key lessons from the consultation include the need for efficiency when targeting informants through rapid identification of key stakeholders. However, this must be balanced with inclusivity and representativeness, which require continuous tracking of who participates, paired with flexibility to maximize potential for reaching consensus that enables the strengthening of the sanitation sector

The Topology of Foliations Formed by the Generic K-Orbits of a Subclass of the Indecomposable MD5-Groups

The present paper is a continuation of [13], [14] of the authors. Specifically, the paper considers the MD5-foliations associated to connected and simply connected MD5-groups such that their Lie algebras have 4-dimensional commutative derived ideal. In the paper, we give the topological classification of all considered MD5-foliations. A description of these foliations by certain fibrations or suitable actions of $\mathbb{R}^{2}$ and the Connes' C*-algebras of the foliations which come from fibrations are also given in the paper.Comment: 20 pages, no figur

Linkages between sanitation and the Sustainable Development Goals: a case study of Brazil

This paper identifies opportunities from targeted and integrated sanitation action to achieve the Sustainable Development Goals (SDGs). This is contextualised to the case of Brazil through a systematic approach applied to the sanitation sector that considers the range of infrastructure, management services and people involved in different phases of the service chain, from municipal wastewater containment to safe disposal or re‐use. Articulating the social, economic and environmental dimensions of sanitation, this study analyses their links with each of the 169 SDG targets. We demonstrate that 87 targets across 16 goals require action in Brazil's sanitation sector to achieve the SDGs. Furthermore, we identify synergies between sanitation and 124 targets in four domains: basic services for resilience building, equity and empowerment, pollution reduction and waste reuse and economic well‐being. Key results include the need for Brazil to invest in closed‐loop systems that valorise waste as a resource and the need to multiply efforts in the integrated provision of basic services in low‐income areas most affected by the lack of access to adequate sanitation. The links identified are supported by the compiled evidence of published research. The analysis of linkages through this structured approach aims to highlight opportunities for strategic governance action to support policy harmonisation and partnerships across Brazil's sanitation sector and beyond. With this research, we show that establishing linkages among the SDGs provides an adaptable framework that can support policy‐makers and practitioners seeking to deliver on the 2030 Agenda