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Periodontal disease affects 42% of adults in the United States. Both the periodontal microbiome and the host immune inflammatory response may be influenced by overweight/obesity status. This retrospective analysis sought to determine the associations of periodontal disease parameters with body mass index (BMI) and obesity status in patients undergoing periodontal maintenance therapy. The records of 418 patients who were undergoing periodontal maintenance after periodontitis treatment were examined, and the patients' demographic characteristics (sex, age, and race/ethnicity), self-reported BMI, periodontal disease condition, number of sites with probing depth ≥ 4 mm, missing teeth, and sites with bleeding on probing (BOP) were recorded. Patients were determined to have active moderate to severe periodontitis if they presented with 2 or more sites in 2 different quadrants with clinical attachment loss ≥ 5 mm and probing depth ≥ 5 mm. Individuals were also categorized into 3 groups: underweight/normoweight, BMI25; overweight, BMI 25 ≤ 30; or obese, BMI ≥ 30. In the study population, BMI ranged from 16.827 to 51.389. The periodontitis status was not significantly associated with a BMI status of overweight (odds ratio [OR] = 1.388 [95% CI, 0.961- 2.006]) or obese (OR = 1.168 [95% CI, 0.77-1.757]). Female sex (OR = 0.561 [95% CI, 0.343-0.918]) and age (OR = 0.983 [95% CI, 0.967-0.999]) were negatively associated with active periodontitis status. Obese patients demonstrated significantly more sites with BOP than either underweight/normoweight or overweight patients, and a BMI indicating obesity was associated with increasing age (P0.001) and higher number of missing teeth (P = 0.0064). In a population of patients undergoing periodontal maintenance therapy, BMI was associated with age and missing teeth, and obese status was associated with a significantly higher number of sites with BOP.

Background \ud The menstrual needs of girls and women are important to health, education, and well-being. Unmet need and harm from poor menstrual health in low-and- middle-income countries have been documented, but with little empirical research undertaken in high income countries. Continuing austerity in the UK suggests menstruators are likely more vulnerable to ‘period poverty’ than previously, with the COVID-19 pandemic assumed to exacerbate the situation. \ud Aim \ud To explore the menstrual experiences and perceptions of women in the UK who are living under circumstances of deprivation, alongside views of staff working in organisations supporting these women, to understand whether women’s menstrual needs are met. \ud Methods\ud A qualitative study was conducted in an inner-city in NW England. Three focus group discussions and 14 in-depth interviews were conducted across three study sites supporting impoverished women. Data was analysed thematically.\ud Results\ud Themes were: reflections on menstruation; affordability of products; access to public facilities; organisational support; potential solutions. Many women perceived menstruation as a burden in three aspects: physical discomfort and pain; psychological anxiety; and shame and stigma. Managing menstruation was difficult due to cost relative to low incomes, with food, heating and lighting prioritised, leaving women improvising with materials or wearing products for longer than desired. Most suggested that products should be free, often remarking if men required similar items this would happen. Most women were unaware supporting organisations provided free products. Staff felt the small range of products offered did not meet client needs and were ill-prepared to have conversations on products and clients’ menstrual needs. \ud Conclusion\ud Impoverished women lack the necessary resources to manage their menses well which negatively impacts their health and brings stress, embarrassment, and shame. Support, including access to free products, is needed at both local and national level to help impoverished women manage their menstrual hygiene.

Kenya has enshrined the right to sanitation in the 2010 constitution. Achieving this requires scaling up infrastructure and models of delivery beyond sewer networks that have previously been the focus. In Kenya, two enterprises, Sanergy and Sanivation, have been providing new forms of off-grid services with container-based sanitation (CBS). This paper uses a political economy analysis to understand the incentives, institutions and power dynamics that are enabling or constraining the potential for such off-grid sanitation models. The paper outlines six core problems to be addressed in the pursuit of scaling up: fragmented governance; sustainability of CBS enterprise models; service delivery planning in informal settlements; personal power rather than institutions in decision-making; vested local interests; and land tenure and political connection. It discusses how stakeholders might work collaboratively to progressively address or recognise these issues.

Supplemental Material, sj-pdf-1-chc-10.1177_13674935211003774 for DigiKnowIt News: Educating youth about pediatric clinical trials using an interactive, multimedia educational website by Alison E. Parker, Tracy M. Scull and Abigail M. Morrison in Journal of Child Health Care

Providing safe sanitation in the developing world is still a major hurdle to achieving Sustainable Development Goal number six, with 61% of the global population lacking safely managed sanitation services. Circular economy in the context of sanitation focuses on the whole sanitation chain which includes the provision of toilets, the collection of waste, treatment and transformation into sanitation-derived products including fertiliser, fuel and clean water. As well as potentially reducing the cost of toilet provision, a circular economy approach also has the potential to enable positive environmental and health impacts, unlike other systems where waste may be discharged untreated into the environment. The implementation of a system level transformation is not simple, considering operator capacity, lack of funding, slowly growing acceptance by local communities, and a policy landscape which can be inconsistent in its support for the circular economy. As India invests in long-term infrastructure to improve citizens’ quality of life (e.g., Swachh Bharat Mission), it could incorporate circular economy principles into the design of infrastructure, creating effective urban nutrient and material cycles, enhancing economic development and welfare. This represents a significant opportunity for government and businesses in India to develop circular sanitation infrastructure to recover and valorise biological nutrients. After collecting information from five case studies across India, covering different treatment technologies, waste-derived products, markets and contexts; this research identifies the main barriers and enablers for circular sanitation business models to succeed. Whilst there were many different institutional and technological arrangements, common issues of managing and enforcing incoming waste and competing with chemical fertilisers were found.

Highlights • Co-combustion analysis was investigated using a bench-scale combustor test rig. • Raw human faeces (FC) contained 73.9 ± 4.4 wt% moisture as received basis. • Blending with wood dust (WD) in a 50:50 ratio reduced moisture levels by ∼40%. • Minimum acceptable blend for combustion without prior drying is 30:70 WD:FC. • Fuel burn rates are 3.18–4.49 g/min for all the blends at air flow of 12–18 L/min. • Oxygen, potassium and calcium are the most abundant elements in faecal ash., Fuel blending is a widely used approach in biomass combustion, particularly for feedstocks with low calorific value and high moisture content. In on-site sanitation technologies, fuel blending is proposed as a pre-treatment requirement to reduce moisture levels and improve the physiochemical properties of raw faeces prior to drying. This study investigates the co-combustion performance of wood dust: raw human faeces blends at varying air-to-fuel ratios in a bench-scale combustor test rig. It concludes with ash composition analyses and discusses their potential application and related problems. The study shows that a 50:50 wood dust (WD): raw human faeces (FC) can reduce moisture levels in raw human faeces by ∼40% prior to drying. The minimum acceptable blend for treating moist faeces without prior drying at a combustion air flow rate of 14–18 L/min is 30:70 WD: FC. For self-sustained ignition and flame propagation, the minimum combustion temperature required for conversion of the fuel to ash is ∼400 °C. The most abundant elements in faecal ash are potassium and calcium, while elements such as nickel, aluminium and iron are in trace quantities. This suggests the potential use of faecal ash as a soil conditioner, but increases the tendency for fly ash formation and sintering problems.

The “Reinvent the Toilet Challenge” set by the Bill & Melinda Gates Foundation aims to bring access to adequate sanitary systems to billions of people. In response to this challenge, on-site sanitation systems are proposed and being developed globally. These systems require in-situ thermal treatment, processes that are not well understood for human faeces (HF). Thermogravimetric analysis has been used to investigate the pyrolysis, gasification and combustion of HF. The results are compared to the thermal behaviour of simulant faeces (SF) and woody biomass (WB), along with the blends of HF and WB. Kinetic analysis was conducted using non-isothermal kinetics model-free methods, and the thermogravimetric data obtained for the combustion of HF, SS and WB. The results show that the devolatilisation of HF requires higher temperatures and rates are slower those of WB. Minimum temperatures of 475 K are required for fuel ignition. HF and SF showed similar thermal behaviour under pyrolysis, but not under combustion conditions. The activation energy for HF is 157.4 kJ/mol, relatively higher than SS and WB. Reaction order for HF is lower (n = 0.4) to WB (n = 0.6). In-situ treatment of HF in on-site sanitary systems can be designed for slow progressive burn.

Early infection from enteropathogens is recognised as both a cause and effect of infant malnutrition. Specifically, evidence demonstrates associations between growth shortfalls and Campylobacter infection, endemic across low-income settings, with poultry a major source. Whilst improvements in water, sanitation and hygiene (WASH) should reduce pathogen transmission, interventions show inconsistent effects on infant health. This cross-sectional, formative study aimed to understand relationships between infant Campylobacter prevalence, malnutrition and associated risk factors, including domestic animal husbandry practices, in rural Ethiopia. Thirty-five households were visited in Sidama zone, Southern Nations, Nationalities and Peoples’ region. Infant and poultry faeces and domestic floor surfaces (total = 102) were analysed for presumptive Campylobacter spp. using selective culture. Infant anthropometry and diarrhoeal prevalence, WASH facilities and animal husbandry data were collected. Of the infants, 14.3% were wasted, 31.4% stunted and 31.4% had recent diarrhoea. Presumptive Campylobacter spp. was isolated from 48.6% of infant, 68.6% of poultry and 65.6% of floor surface samples. Compared to non-wasted infants, wasted infants had an increased odds ratio (OR) of 1.41 for a Campylobacter-positive stool and 1.81 for diarrhoea. Positive infant stools showed a significant relationship with wasting (p = 0.026) but not stunting. Significant risk factors for a positive stool included keeping animals inside (p = 0.027, OR 3.5), owning cattle (p = 0.018, OR 6.5) and positive poultry faeces (p

Menstrual hygiene management (MHM) has gained some attention and several literature reviews have been published. However, both original papers and reviews tend to focus on absorbent access and use and not on the disposal of menstrual waste. This review aims to fill a gap in the water, sanitation and hygiene (WASH) sector by bringing a focus specifically on menstrual hygiene safe disposal in low- and middle-income countries (LMIC). We reviewed published literature since 2002 on menstrual hygiene with a focus on menstrual waste management and menstrual absorbent disposal in LMIC. Database searches were conducted of both peer reviewed literature and grey literature, in addition to hand searching of references of relevant earlier literature reviews. In total 152 articles and reports were identified and 75 met the inclusion criteria and was included in the final review. Existing polices on MHM was also reviewed with a focus on India and South Africa. The review showed that disposal of menstrual waste is often neglected MHM and sanitation value chains, leading to improper disposal and negative impacts on users, the sanitation systems and the environment. Findings call for further research to gain better understandings of MHM waste streams, disposal behaviors, absorbent materials and waste management technologies to deliver health, safety, mobility and dignity for women and girls.

In many developing countries, including South Africa, water scarcity has resulted in poor sanitation practices. The majority of the sanitation infrastructures in those regions fail to meet basic hygienic standards. This along with the lack of proper sewage/wastewater infrastructure creates significant environmental and public health concerns. A self-sustained, waterless “Nano Membrane Toilet” (NMT) design was proposed as a result of the “Reinvent the Toilet Challenge” funded by the Bill and Melinda Gates Foundation. A “cradle-to-grave” life cycle assessment (LCA) approach was adopted to study the use of NMT in comparison with conventional pour flush toilet (PFT) and urine-diverting dry toilet (UDDT). All three scenarios were applied in the context of South Africa. In addition, a Quantitative Microbial Risk Assessment (QMRA) was used to reflect the impact of the pathogen risk on human health. LCA study showed that UDDT had the best environmental performance, followed by NMT and PFT systems for all impact categories investigated including human health, resource and ecosystem. This was mainly due to the environmental credits associated with the use of urine and compost as fertilizers. However, with the incorporation of the pathogen impact into the human health impact category, the NMT had a significant better performance than the PFT and UDDT systems, which exhibited an impact category value 4E + 04 and 4E + 03 times higher, respectively. Sensitivity analysis identified that the use of ash as fertilizer, electricity generation and the reduction of NOx emissions were the key areas that influenced significantly the environmental performance of the NMT system.

Highlights • A probabilistic model is developed to assess the performance of an NMT. • Energy and environmental performance uncertainties of the system are qualified. • A realistic prediction of the energy and environmental performance of the system. • Probabilistic approach can be applied in other complex engineering systems., A probabilistic modelling approach was developed and applied to investigate the energy and environmental performance of an innovative sanitation system, the “Nano-membrane Toilet” (NMT). The system treats human excreta via an advanced energy and water recovery island with the aim of addressing current and future sanitation demands. Due to the complex design and inherent characteristics of the system’s input material, there are a number of stochastic variables which may significantly affect the system’s performance. The non-intrusive probabilistic approach adopted in this study combines a finite number of deterministic thermodynamic process simulations with an artificial neural network (ANN) approximation model and Monte Carlo simulations (MCS) to assess the effect of system uncertainties on the predicted performance of the NMT system. The joint probability distributions of the process performance indicators suggest a Stirling Engine (SE) power output in the range of 61.5–73 W with a high confidence interval (CI) of 95%. In addition, there is high probability (with 95% CI) that the NMT system can achieve positive net power output between 15.8 and 35 W. A sensitivity study reveals the system power performance is mostly affected by SE heater temperature. Investigation into the environmental performance of the NMT design, including water recovery and CO2/NOx emissions, suggests significant environmental benefits compared to conventional systems. Results of the probabilistic analysis can better inform future improvements on the system design and operational strategy and this probabilistic assessment framework can also be applied to similar complex engineering systems.

This article describes the design and commissioning of a micro-combustor for energy recovery from human faeces, which can operate both in updraft and downdraft modes. Energy recovery from faecal matter via thermochemical conversion has recently been identified as a feasible solution for sanitation problems in low income countries and locations of high income countries where access to sewage infrastructures is difficult or not possible. This technology can be applied to waterless toilets with the additional outcome of generating heat and power that can be used to pre-treat the faeces before their combustion and to ensure that the entire system is self-sustaining. The work presented here is framed within the Nano Membrane Toilet (NMT) project that is being carried out at Cranfield University, as part of the Reinvent the Toilet Challenge of the Bill and Melinda Gates Foundation. For this study, preliminary trials using simulant faeces pellets were first carried out to find out the optimum values for the main operating variables at the scale required by the process, i.e. a fuel flowrate between 0.4 and 1.2 g/min of dry faeces. Parameters such as ignition temperature, residence time, and maximum temperature reached, were determined and used for the final design of the bench-scale combustor prototype. The prototype was successfully commissioned and the first experimental results, using real human faeces, are discussed in the paper.

This paper reports key advances in the study of the representation theory of the symplectic blob algebra. For suitable specialisations of the parameters we construct four large families of homomorphisms between cell modules. We hence find a large family of non-semisimple specialisations. We find a minimal poset (i.e. least number of relations) for the symplectic blob as a quasi-hereditary algebra., 45 pages. arXiv admin note: text overlap with arXiv:0807.4101

We find the blocks for the symplectic blob algebra for all specialisations of the parameters over the complex numbers. We determine Gram determinants for the cell modules. We also show that the algebra is semisimple over the complex numbers unless at least one of the quantisation parameters, or the sum or difference of two of the parameters is integral or $q$ is a root of unity. We also find decomposition numbers in many of the $q$ generic cases., 41 pages, 17 figures

Poor sanitation is one of the major hindrances to the global sustainable development goals. The Reinvent the Toilet Challenge of the Bill and Melinda Gates Foundation is set to develop affordable, next-generation sanitary systems that can ensure safe treatment and wide accessibility without compromise on sustainable use of natural resources and the environment. Energy recovery from human excreta is likely to be a cornerstone of future sustainable sanitary systems. Faeces combustion was investigated using a bench-scale downdraft combustor test rig, alongside with wood biomass and simulant faeces. Parameters such as air flow rate, fuel pellet size, bed height, and fuel ignition mode were varied to establish the combustion operating range of the test rig and the optimum conditions for converting the faecal biomass to energy. The experimental results show that the dry human faeces had a higher energy content (∼25MJ/kg) than wood biomass. At equivalence ratio between 0.86 and 1.12, the combustion temperature and fuel burn rate ranged from 431 to 558°C and 1.53 to 2.30g/min respectively. Preliminary results for the simulant faeces show that a minimum combustion bed temperature of 600±10°C can handle faeces up to 60wt.% moisture at optimum air-to-fuel ratio. Further investigation is required to establish the appropriate trade-off limits for drying and energy recovery, considering different stool types, moisture content and drying characteristics. This is important for the design and further development of a self-sustained energy conversion and recovery systems for the NMT and similar sanitary solutions.

We investigated cultural influences on the implementation of water safety plans (WSPs) using case studies from WSP pilots in India, Uganda and Jamaica. A comprehensive thematic analysis of semi-structured interviews (n = 150 utility customers, n = 32 WSP ‘implementers’ and n = 9 WSP ‘promoters’), field observations and related documents revealed 12 cultural themes, offered as ‘enabling’, ‘limiting’, or ‘neutral’, that influence WSP implementation in urban water utilities to varying extents. Aspects such as a ‘deliver first, safety later’ mind set; supply system knowledge management and storage practices; and non-compliance are deemed influential. Emergent themes of cultural influence (ET1 to ET12) are discussed by reference to the risk management, development studies and institutional culture literatures; by reference to their positive, negative or neutral influence on WSP implementation. The results have implications for the utility endorsement of WSPs, for the impact of organisational cultures on WSP implementation; for the scale-up of pilot studies; and they support repeated calls from practitioner communities for cultural attentiveness during WSP design. Findings on organisational cultures mirror those from utilities in higher income nations implementing WSPs – leadership, advocacy among promoters and customers (not just implementers) and purposeful knowledge management are critical to WSP success.

With about 2.4 billion people worldwide without access to improved sanitation facilities, there is a strong incentive for development of novel sanitation systems to improve the quality of life and reduce mortality. The Nano Membrane Toilet is expected to provide a unique household-scale system that would produce electricity and recover water from human excrement and urine. This study was undertaken to evaluate the performance of the conceptual energy and water recovery system for the Nano Membrane Toilet designed for a household of ten people and to assess its self-sustainability. A process model of the entire system, including the thermochemical conversion island, a Stirling engine and a water recovery system was developed in Aspen Plus®. The energy and water recovery system for the Nano Membrane Toilet was characterised with the specific net power output of 23.1Wh/kgsettledsolids and water recovery rate of 13.4dm3/day in the nominal operating mode. Additionally, if no supernatant was processed, the specific net power output was increased to 69.2Wh/kgsettledsolids. Such household-scale system would deliver the net power output (1.9–5.8W). This was found to be enough to charge mobile phones or power clock radios, or provide light for the household using low-voltage LED bulbs.

To extend water, sanitation and hygiene services to all, technological innovations are required which take into account a diverse range of stakeholder perspectives. We report the experiences of an intervention which sought to build capacity in the assessment and introduction of technologies in Uganda, Ghana and Burkina Faso by developing the Technology Applicability Framework (TAF), a tool which culminates in a multi-stakeholder scoring workshop. The project also used Learning Alliances to build capacity around technology introduction. This paper explores how stakeholder attitudes changed through the project and evaluates the Learning Alliance approach. It finds that whilst the intervention did manage to connect stakeholders in a novel way, uptake of the TAF may be hampered by a lack of government involvement in the earliest stages of the project.

Material complementari del cas estudi "Faecal sludge management in Lusaka, Zambia", part component del llibre "Case studies for developing globally responsible engineers"

Hydrogeological knowledge is vital for developing sustainable groundwater supplies globally. This is particularly true for the underpinning data from basement complex areas, such as those in Liberia, with complex hydrogeology and where past political instability has led to information and knowledge loss. The authors are therefore appreciative of the attention paid to their paper (Elster et al 2014) by Beeson and Jones (2014) and welcome the opportunity it provides for discussion on this important topic.

Pumped flowing fluid electrical conductivity (FFEC) logs, also known as pumped borehole dilution testing, is an experimentally easy‐to‐perform approach to evaluating vertical variations in the hydraulic conductivity of an aquifer. In contrast to the simplicity of the logging equipment, analysis of the data is complex and laborious. Current methods typically require repeated solution of the advection‐dispersion equation (ADE) for describing the flow in the borehole and comparison with the experimental results. In this paper, we describe a direct solution for determining borehole fluid velocity that bypasses the need for complex numerical computation and repetitive optimization. The method rests on the observation that, while solving the ADE for concentration profile in the borehole (as required for modeling and combined methods) is computationally challenging, the solution for flow distribution along the length of the borehole given concentration data is straightforward. The method can accommodate varying borehole diameters, and uses the fact that multiple profiles are taken in the standard logging approach to reduce the impact of noise. Data from both a simulated borehole and from a field test are successfully analyzed. The method is implemented in a spreadsheet, which is available as supporting information material to this paper.

In this note, we consider the Lyndon--Hochschild--Serre spectral sequence corresponding to the first Frobenius kernel of an algebraic group G, computing the extensions between simple $G$-modules. We state and discuss a conjecture that $E_2=E_\infty$ and provide general conditions for low-dimensional terms on the $E_2$-page to be the same as the corresponding terms on the $E_{\infty}$-page, i.e. its abutment., Comment: 6 pages

Written assignments are usually not incorporated into large undergraduate courses due to the significant amount of time and resources their administration requires. Our presentation will reveal how we addressed these challenges for our written assignment in a large (1800 students) first-year undergraduate biology course. Our students write a proposal, receive feedback from their teaching assistant, and submit a revised proposal. We will discuss how we designed and administer the assignment, how it is scaffolded into the laboratories associated with the course, and how we train over 30 course TAs. Additionally, we will explore how we have measured the effect of this assignment on students’ writing and their scientific reasoning, using both student surveys and quantitative methods.

We analyse the recursive formula found for various Ext groups for $\SL_2(k)$, $k$ a field of characteristic $p$, and derive various generating functions for these groups. We use this to show that the growth rate for the cohomology of $\SL_2(k)$ is at least exponential. In particular, $\max \{\dim \Ext^i_{\SL_2(k)}(k, \Delta(a))\mid a,i \in \N \}$ has (at least) exponential growth for all $p$. We also show that $\max \{\dim \Ext^i_{\SL_2(k)}(k, \Delta(a))\mid a\in \N \}$ for a fixed $i$ is bounded., Comment: 21 pages

Groundwater forms 70% of the world's freshwater supply, and is typically much cleaner than surface water supplies. It is therefore a key water resource that needs to be carefully managed. In urban areas, groundwater can be overexploited by industry, leading to degradation in quality. In order to regulate groundwater use, an understanding of the key parameters that control groundwater flow is required. This paper focuses on methods of measuring some of these parameters, so more accurate groundwater flow models can be created. The results from standard techniques are compared to other, lower technology methods. The Chalk aquifer of East Yorkshire in the UK is used as a case study. It is hoped that the lessons and principals learned by groundwater regulators in the UK and other developed countries can be used to avoid similar problems in the developing world as urban populations increase.

This report is based upon a 10 month project assessing the vulnerability of WSUP (Water and Sanitation for the Urban Poor) projects to climate change, converting climate change predictions into recommended adaptations. The findings are based on a literature review and field work in Kenya, Madagascar and Zambia, undertaking focus groups, stakeholder interviews and observations. This report synthesises the science of climate change, the impacts of climate change on drinking water and sanitation, how to climate proof water and sanitation services and how to adapt: WSUP: Water and Sanitation for the Urban Poor

This paper reviews a result of Jensen on characters of some tilting modules for $\SL_3(k)$, where $k$ has characteristic at least five and fills in some gaps in the proof of this result. We then apply the result to finding some decomposition numbers for three part partitions for the symmetric group and the Hecke algebra. We review what is known for characteristic two and three. The quantum case is also considered: analogous results hold for the mixed quantum group where $q$ is an $l$th root of unity with $l$ at least three and thus also hold for the associated Hecke algebra., 18 pages, 8 figures

We study the Delta-filtered modules for the Auslander algebra of k[T]/T^n\rtimes C_2 where C_2 is the cyclic group of order two. The motivation for this is the bijection between parabolic orbits in the nilradical of a parabolic subgroup of SL_n and certain Delta-filtered modules for the Auslander algebra of k[T]/T^n as found by Hille and Roehrle and Bruestle et al. Under this bijection, the Richardson orbit (i.e. the dense orbit) corresponds to the Delta-filtered module without self-extensions. It has remained an open problem to describe such a correspondence for other classical groups. In this paper, we establish the Auslander algebra of k[T]/T^n\rtimes C_2 as the right candidate for the orthogonal groups. In particular, for any parabolic subgroup of an orthogonal group we construct a map from parabolic orbits to Delta-filtered modules and show that in the case of the Richardson orbit, the result has no self-extensions. One of the consequences of our work is that we are able to describe the extensions between special classes of Delta-filtered modules. In particular, we show that these extensions can grow arbitrarily large., 25 pages

We classify all homomorphisms between Weyl modules for SL_3(k) when k is an algebraically closed field of characteristic at least three, and show that the Hom-spaces are all at most one-dimensional. As a corollary we obtain all homomorphisms between Specht modules for the symmetric group when the labelling partitions have at most three parts and the prime is at least three. We conclude by showing how a result of Fayers and Lyle on Hom-spaces for Specht modules is related to earlier work of Donkin for algebraic groups., 41 pages, 2 colour figures, 25 black and white figures

In this paper we consider how the \nabla-, \Delta- and global dimensions of a quasi-hereditary algebra are interrelated. We first consider quasi-hereditary algebras with simple preserving duality and such that if \mu < \lambda then \nabla fd(L(\mu)) < \nabla fd(L(\lambda)) where \mu, \lambda are in the poset and L(\mu), L(\lambda) are the corresponding simples. We show that in this case the global dimension of the algebra is twice its \nabla-filtration dimension. We then consider more general quasi-hereditary algebras and look at how these dimensions are affected by the Ringel dual and by two forms of truncation. We restrict again to quasi-hereditary algebras with simple preserving duality and consider various orders on the poset compatible with quasi-hereditary structure and the \nabla-, \Delta- and injective dimensions of the simple and the costandard modules., Comment: 18 pages, uses xypic

Let G be a linear algebraic group over an algebraically closed field of characteristic p whose corresponding root system is irreducible. In this paper we calculate the Weyl filtration dimension of the induced G-modules, \nabla(\lambda) and the simple G-modules L(\lambda), for \lambda a regular weight. We use this to calculate some Ext groups of the form Ext^*(\nabla(\lambda),\Delta(\mu)), Ext^*(L(\lambda),L(\mu)), and Ext^*(\nabla(\lambda), \nabla(\mu)), where \lambda, \mu are regular and \Delta(\mu) is the Weyl module of highest weight \mu. We then deduce the projective dimensions and injective dimensions for L(\lambda), \nabla(\lambda) and \Delta(\lambda) for \lambda a regular weight in associated generalised Schur algebras. We also deduce the global dimension of the Schur algebras for GL_n, S(n,r), when p>n and for S(mp,p) with m an integer., Comment: 17 pages, uses amsart v. 2.08

Let $k$ be an algebraically closed field of characteristic $p$, possibly zero, and $G=q$-$\GL_3(k)$, the quantum group of three by three matrices as defined by Dipper and Donkin. We may also take $G$ to be $\GL_3(k)$. We first determine the extensions between simple $G$-modules for both $G$ and $G_1$, the first Frobneius kernel of $G$. We then determine the submodule structure of certain induced modules, $\hat{Z}(\lambda)$, for the infinitesimal group $G_1B$. We induce this structure to $G$ to obtain a good $l$-filtration of certain induced modules, $\nabla(\lambda)$, for $G$. We also determine the homomorphisms between induced modules for $G$., Comment: 2 figures, 33 pages, uses xypic

We study certain Δ-filtered modules for the Auslander algebra of k[T]/Tn⋊C2 where C2 is the cyclic group of order two. The motivation of this lies in the problem of describing the P-orbit structure for the action of a parabolic subgroup P of an orthogonal group. For any parabolic subgroup of an orthogonal group we construct a map from parabolic orbits to Δ-filtered modules and show that in the case of the Richardson orbit, the resulting module has no self-extensions.

We investigated cultural influences on the implementation of water safety plans (WSPs) using case studies from WSP pilots in India, Uganda and Jamaica. A comprehensive thematic analysis of semi-structured interviews (n=150 utility customers, n=32 WSP ‘implementers’ and n=9 WSP ‘promoters’), field observations and related documents revealed 12 cultural themes, offered as ‘enabling’, ‘limiting’, or ‘neutral’, that influence WSP implementation in urban water utilities to varying extents. Aspects such as a ‘deliver first, safety later’ mind set; supply system knowledge management and storage practices; and non-compliance are deemed influential. Emergent themes of cultural influence (ET1 to ET12) are discussed by reference to the risk management, development studies and institutional culture literatures; by reference to their positive, negative or neutral influence on WSP implementation. The results have implications for the utility endorsement of WSPs, for the impact of organisational cultures on WSP implementation; for the scale-up of pilot studies; and they support repeated calls from practitioner communities for cultural attentiveness during WSP design. Findings on organisational cultures mirror those from utilities in higher income nations implementing WSPs – leadership, advocacy among promoters and customers (not just implementers) and purposeful knowledge management are critical to WSP success.

It is estimated that 61% of the world population lacks access to safely managed sanitation and that in low-income countries (LICs) only 6.7% of the population is connected to a sewerage network. Container-based sanitation (CBS) systems have shown great potential for increasing access to sanitation in densely populated urban slums given that they do not require permanent infrastructures. Resource recovery is usually an essential part of CBS systems to provide sustainable faecal sludge management. Transforming human excreta into fertilisers creates value from faecal sludge while producing an organic soil amendment, addressing both sanitation and soil fertility challenges. Soil amendments made from organic residues are however known to be difficult to market profitably. This thesis therefore investigated the properties of human excreta derived fertilisers (HEDF) and the opportunities and challenges to their commercialisation in LIC. Nutrient characterisation of composts, anaerobic digestate and vermicompost from two CBS ventures showed significant differences in nutrient content between these three HEDF types. Pathogen and heavy metal analyses demonstrated that there is no pollution threat from HEDF when produced according toWHO guidelines. Field and glasshouse crop trials demonstrated the positive effect HEDF can have on crops and soil health. These benefits however do not currently translate into their commercial value. A case study approach was used to identify barriers and enabling conditions faced by two CBS organisations that successfully produce and sell HEDF. The low market value of compost prevented both organisations from recovering treatment costs from HEDF sales. One major barrier to wider adoption of HEDF use was the lack of regulations or certifications specific to this type of fertiliser. Perception challenges exist because of the potentially harmful components human excreta contain such as pathogens and heavy metals. It is therefore essential to create a way of proving or guaranteeing the quality and safety of HEDF products. The value of qualityassuring schemes for HEDF became evident when applying the Biosolids Assurance Scheme from the UK to HEDF, which helped identify a contamination issue in one of the treatment sites considered.

About 2.7 billion people worldwide have access to onsite sanitation technologies, and that number is expected to increase to 5 billion by 2030. In Sub-Saharan Africa, 65-100% of sanitation access in urban areas is provided through the onsite technologies. It is evident that faecal sludge management is of a critical need that must be addressed. Clean Team, a subsidiary company of Water and Sanitation for Urban poor (WSUP), operates in Kumasi, Ghana by providing household portable container toilets at subsidised fees. This research investigated toilet waste treatment options for Clean Team, in the event that it expands into towns where there is no treatment plant at all. The study presented the results of the performance of the two technologies, Sistema Biobolsa and BIOROCK, installed and operated under the ambient conditions in Kumasi. With hydraulic retention time of 10 days, the Sistema Biobolsa achieved removal efficiency of 79%, 93%, 90%, 61% and 64% for the Chemical Oxygen Demand (COD), Ammonium Nitrogen (NH₄-N), Total Solids, Total Suspended Solid (TSS) and Alkalinity respectively. With regards to BIOROCK system, at hydraulic retention time of 25 days, the system achieved removal efficiency of 73%, 87%, 86% and 51% for the COD, NH₄-N, TS and TSS respectively. The study recorded 46 % biogas (methane) production by volume from the Sistema Biobolsa digesters, in spite of Clean Team’s chemical additive (odour suppressant). Furthermore, the study also shown 100% seed germination in the outflow wastewater from the Sistema Biobolsa gravel filter beds, whilst BIOROCK shown a seed germination at 10% dilution of outflow wastewater from the secondary tank (filtration process). Taken together these results , there are strong indication of the occurrence of biological processes in spite of the presence of the chemical additive and provide confidence that waste of this type can be treated by flowsheet which included biological processes. The effluent quality from the both technologies met some of the Ghana Environmental Protection Agency (GEPA) guidelines but not others. The study suggested that any stand-alone deployment of these systems (thus, where there is no existing wastewater treatment works), would require a parallel sludge management system such as drying beds. MSc by Research

The global water and sanitation sector is faced with numerous problems. Evident from Sub-Sahara Africa is the lack of access to potable water and improved sanitation which has made water coverage and sanitation a worry for most governments in low and middle-income countries. Climate change will exacerbate these problems especially in the urban poor communities. There is therefore the need to investigate how to make urban WASH services climate proof. In line with achieving this aim, part of this work assessed the existing WASH vulnerabilities, assessed the potential impacts of developed hydrological scenarios on the existing vulnerabilities and developed recommendations for various stakeholders using the Rapid Climate Adaptation Assessment (RCAA) methodology. The other part of this work assessed the adaptive capacity of the urban WASH sector by applying the Adaptive capacity wheel (ACW) methodology. In the application of these two methodologies, qualitative empirical data were collected from semi-structured interviews, direct observations and focus group discussions. The empirical data collected helped to understand the stakeholders‟ climate change awareness, the linkages in the local vulnerabilities, and ways to enhance the adaptive capacity of the WASH sector. This research argues that the vulnerabilities of the WASH services are similar within and across the ecological zones in Ghana. These vulnerabilities resulted from intermittent water supply, poorly managed solid waste and lack of spatial planning which are problems in urban poor WASH management. Though these vulnerabilities were arrived by simple hydrological scenario, they show the need for adaptation measures to be incorporated into urban poor WASH planning. To integrate adaptation measures to achieve resilience, this work further argues that the adaptive capacity of the sector can be enhanced by improving the learning capacity and motivation of stakeholders as well as empowering larger-scale institutions to provide structures and guidance at the lower- and individual level. PhD in Water

For the past 30 years the dominant approach to managing rural water services in low and lower middle income countries has been the community management approach. Yet there is increasing evidence the model is not fit for purpose as too many services fail. The next generation ideas for community management emphasise the need for continuous on-going support to communities – an approach known as the community management plus approach. This thesis tests and develops this next generation community management plus paradigm. It analyses field data from twenty case studies of ‘reportedly successful’ community management programmes across seventeen states in India. Bringing together data from 2,355 household surveys, 272 interviews and 130 focus groups it provides a synthesis that assesses the type and level of support found in successful examples of community management. The evidence from these case studies demonstrates that communities receive significant recurrent subsidy covering between 7-48% of operational expenditure. This is in marked contrast to the conventional principles of community management whereby communities cover 100% of these costs. Analysis of organisation types also shows how community management has been shaped by the devolution of governance in rural India. Many community management programmes involve a structural overlap between the local self- government institution of the Gram Panchayat and water committees. The thesis argues this represents a shift to the ‘institutionalised co-production’ of rural water services, involving both the state and private citizens in public service delivery. Overall, the research shows that successful community management in India involves continuous on-going support as per the community management plus paradigm. However this has required the nesting of the model within the broader system of local self-government which blurs the lines between public and community management.

Increasing water scarcity and contamination pose a danger to the health of a considerable number of the world’s population. Decisions regarding water supply and treatment are usually made in a top-down fashion. The end-users, however, still react to these decisions and the provided water facilities and treatment options. These reactions include the rejection of certain water supplies or treatment options and own provisions for a supply with safe and sufficient drinking water. This study investigates the socio-cultural and economic factors which influence the rural Indian population’s preferences regarding their water supply and treatment. The study has been carried out, employing an ethnographic approach to the field, in two villages in Karnataka, in South India, conducting 18 in depth, problem-centred interviews, participant observation, and two group discussions. The key findings show a ubiquitous lack of education regarding water and related hygiene-measures, water policies and water contamination. This led to uninformed opinions about water supplies and treatment. Socio- cultural factors, along with pragmatic factors such as reliability of water supply and treatment, along with the physical ease of use regarding their operation, were found to be more important for the villagers’ preferences than economic factors. Most households viewed piped water supply as an unreliable source of water, also in terms of water quality. The households and NGO interviewees favoured individual community-based solutions on village level, whereas the political decision-makers were in favour of centralised solutions, usually through piped supply. These findings show a need for long-term, in-depth studies of individual socio-cultural factors and the importance of decentralised and individually fitted water supply and treatment solutions. The fact that perceptions of water supplies and treatment, based on similar concepts could be found in two villages, in entirely differing regions in South India, suggests the significance of these findings beyond Karnataka and the Indian borders.

It is estimated that 2.7 billion people worldwide are served by on-site sanitation facilities that require faecal sludge management. Anaerobic digestion is a treatment mechanism that can provide faecal sludge management, methane production and an effluent digestate rich in nutrients. However, there is a paucity of information regarding the composition of the input faecal sludge which hinders the advancement of anaerobic digestion treatment and downstream nutrient recovery together with a lack of knowledge as to how best to recover these output nutrients in a simple process. Following an initial review to collate composition data for fresh faeces and urine, practical studies examined the physical, biological and chemical composition and variation of four different types of faecal sludge from on-site sanitation facilities. Faecal sludge storage strongly influenced the biodegradability and methane production potential in subsequent anaerobic digestion. However, the high concentrations of ammonium observed in faecal sludge (520-1853 mg NH4-N L- 1 ) were highlighted as a key goal for nutrient recovery and the ability of biochar and clinoptilolite as natural adsorbents for ammonium recovery in a drying bed application were investigated through batch and dynamic studies using synthetic and real digestate. Batch tests observed ammonium uptake of 5 and 12.2 mg NH4-N/g for biochar and clinoptilolite respectively whilst under dynamic experimental conditions the most efficient operation for ammonium recovery was at the longest empty bed contact times (354 minutes), ensuring the maximum fertiliser value was obtained (60g NH4-N/kg clinoptilolite). Nevertheless, clogging occurred rapidly at the surface of the media bed (0.04 – 0.5 kg TS/m2 ), consequently a sacrificial sand layer (0.05 m) was included to increase the longevity of the nutrient recovery system (15 fold increase in TS application rates). It has been demonstrated that clinoptilolite can effectively be used as part of a sludge drying bed configuration to recover nutrients from digestate and the saturated media can be used directly as a fertiliser product or blended with the dried sludge to create a balanced nitrogen, phosphorus and potassium fertiliser product (5.9% NH4-N/ 4.2% P/ ≥6.0% K+ ).

Learning Alliances are a relatively new approach to emerge within the Water, Sanitation and Hygiene (WASH) sector and seek to enhance the institutionalisation and scaling up of innovations in service delivery. In the context of WASH, Learning Alliances place an emphasis on establishing multidisciplinary interconnected platforms for interaction at different institutional levels in the sector, in order to address aspects of service delivery. This thesis examines a case of a project taking place in Burkina Faso, Ghana and Uganda, which used a Learning Alliance approach to programme management. The project was aiming to build the capacity in the area of technology assessment and introduction through action research, in the development of tools which could be used by stakeholders in the sector. The paper draws from forty semi-structured key informant interviews, one focus group discussion and a further 52 Most Significant Change stories (Davis and Dart 2005), conducted among individuals taking part in the project or otherwise exposed to it through dissemination activities. Applying the Learning Alliance approach has meant stakeholders have been able to tailor project innovations to the local context. Capacity has also been built among those taking part in the alliance both in terms of technology assessment and the use of the tools. However, the study has revealed certain difficulties with institutionalising externally developed innovations in a short three year project timeline. Further research is needed to investigate the processes behind diffusion and institutionalisation of innovation in WASH Learning Alliances. Creating a favourable environment for ongoing support and implementation of innovations in service delivery should be a key area of focus for Learning Alliances going forward.

Consumption of unsafe water in developing countries results in considerable number of illnesses and deaths annually. The World Health Organization and the International Water Association are promoting the use of water safety plans (WSPs), a risk management approach aimed at attaining water safety. This study investigated how culture impacts on the implementation of WSPs in these countries. Combining interpretive and critical paradigms resulted in the choice of qualitative methodologies utilizing multiple-case studies. Cases from India, Uganda, and Jamaica are each embedded with three units of analysis: promoters of WSPs, water utilities and their customers. Thematic analysis of data generated from semi-structured interviews, field observations and documents revealed eleven cultural factors impacting on the implementation of WSPs. Analyses of these factors led to various groupings and the subsequent development of a taxonomy categorizing these factors as being either enabling, limiting, or neutral in relation to WSPs. Findings show all the limiting factors to be deviations from the values and principles on which they are built. The findings have also led to the development of a culturally adapted risk management framework. This four-step cyclical & iterative framework is designed to address the impact of culture on the implementation of WSPs. The implementation of WSPs will take time and will require continuous improvement to the process. The successful management of drinking water risks in developing countries will require a broad institutional approach and a concerted effort that involves institutions beyond the water utilities. As such, targeted recommendations are first made towards achievement of good governance. Activities that will lead to the embracement of WSP by stakeholders along with suggestions to attain its institutionalization are also put forward. Recommendations towards addressing negative cultural factors include suggestions on dealing with: pollution causing rituals, bettering storage related practices, addressing excessive water use in rituals, counteracting belief that water should be free, fighting corruption and improving compliance, changing deliver-first safety-later attitude, and improving knowledge management practices.

Improved access to water and sanitation in the worlds slums were among the key targets in the Millennium Development Goals. In Kenya, water is generally accessed in slum areas by filling 20l jerrycans at standposts and water kiosks and carrying back to households, with residents paying up to nine times more than utility bulk water prices and spending large parts of their day collecting water. The aim of this research was to assess consumers’ response and reaction to a series of water delivery mechanisms designed to offer a range of service levels and prices in accessing water in informal settlements. The current situation of residents’ access to water in seven informal settlements in Nairobi and Kisumu was assessed via household surveys and interviews with water providers, both municipal utilities and private operators, supplemented with observation of local practises. A series of innovative water delivery techniques were then designed to suit the prevailing conditions intending to offer price differences and volumetric purchase options. Follow up surveys were then carried out. This research has found that offering lower or alternative prices for water services in informal settlements is difficult due to challenges posed by vested interests and those interested in maintaining current high prices for water, and applying a difference in price was easiest in areas with already poor access to water or a new water kiosk. However, residents responded positively to the water delivery service, evidenced by a strong desire for this to continue and a willingness to assist operators in applying group purchases and volumetric purchases. Where it was possible to implement a difference in price corresponding to service level, consumers recognised their ability to move between service levels depending on variable income, their immediate demand and a simple choice.