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  • The impact of the Coronavirus infectious disease (COVID-19) pandemic on the provision of Inflammatory Bowel Disease (IBD) antenatal care and outcomes of pregnancies in women with IBD

    Steed, Helen; Selinger, CP; Segal, JP; Fraser, A; Collins, P; Gunn, Melanie; Chew, Then Soon; Kerry, Georgina; Patel, Kamal V; Toysam, M; et al. (BMJ, 2021-12-31)
    Background The impact of COVID-19 on pregnant Inflammatory Bowel Disease (IBD) patients is currently unknown. Reconfiguration of services during the pandemic may negatively affect medical and obstetric care. We aimed to examine the impacts on IBD antenatal care and pregnancy outcomes. Methods Retrospective data were recorded in consecutive patients attending for IBD antenatal care including outpatient appointments, infusion unit visits and advice line encounters. Results We included 244 pregnant women with IBD, of which 75 (30.7%) were on biologics in whom the treatment was stopped in 29.3% at a median 28 weeks gestation. In addition 9% of patients were on corticosteroids and 21.5% continued on thiopurines. The care provided during 460 patient encounters was not affected by the pandemic in 94.1% but 68.2% were performed via telephone (compared to 3% pre-pandemic practice; p<0.0001). One-hundred-ten women delivered 111 alive babies (mean 38.2 weeks gestation, mean birthweight 3324grams) with 12 (11.0%) giving birth before week 37. Birth occurred by vaginal delivery in 72 (56.4%) and by caesarean section in 48 (43.6%) cases. Thirty three were elective (12 for IBD indications) and 15 emergency caesarean sections. Breast feeding rates were low (38.6%). Amongst 244 pregnant women with IBD 1 suspected COVID-19 infection was recorded. Conclusion IBD antenatal care adjustments during the COVID-19 pandemic have not negatively affected patient care. Despite high levels of immunosuppression only a single COVID-19 infection occurred. Adverse pregnancy outcomes were infrequent.
  • Longitudinal complications associated with PEG: rate and severity of 30-day and 1-year complications experienced by patients after primary PEG insertion

    Boylan, Conor; Barrett, Diane; Li, Vincent; Merrick, Susan; Steed, Helen (Elsevier, 2021-02-24)
    Background and Aims Percutaneous Endoscopic Gastrostomy (PEG) feeding is utilised in patients with exceptionally poor oral intake but is associated with both short and long-term complications. This study reviews longitudinal PEG complications and compares key subgroups. Methods Single-centre retrospective observational study of all patients receiving PEG insertion between January 2016 and December 2018. Results 306 patients met the inclusion criteria. The mean age at insertion was 67 years. The majority were cared for in their own home (80.4%) by themselves or family (74.9%). 127 PEG tubes were inserted for dysphagia and 165 prophylactically prior to treatment for head and neck cancer. In the first 30 days 16.7% experienced a complication. The most frequently reported was peristomal pain (9.2%). In the first year, 35.6% experienced at least one complication, 12.4% two complications and 6.6% three complications and 6.5% required inpatient treatment for their complication. The most common was pain (14.4%) followed by site weeping, site infection and external overgranulation. Patients with dysphagia took longer to develop complications, had fewer complications and took longer to require management by members of the secondary care team than those with head and neck cancer. Discounting peristomal pain, there was no difference in total complications between patients caring for themselves when compared to those receiving professional input. Conclusion One third of patients will experience a complication related to their PEG tube over 1 year, but the majority are managed in an outpatient setting. This study has implications for planning support services and consenting and counselling patients pre-PEG-insertion.
  • Impact of Covid-19 on water sector projects and practices

    Renukappa, Suresh; Suresh, Subashini; Kamunda, Andrew (Elsevier, 2021-12-31)
    The COVID-19 pandemic has negatively affected world economies. The water industry was adversely affected, with unprecedented slow down and changes to ways of working. However, the pandemic also accelerated positive digital transformation. A qualitative research approach was adopted to analyze data collected from 12 interviewees representing six water sector organizations. The paper provides insight into the impact of COVID-19 on the delivery of water sector projects and how organizational practices have adapted from business as usual.
  • Future directions and requirements for tissue engineering biomaterials

    Arjunan, Arun; Baroutaji, Ahmad; Robinson, John; Praveen, Ayyappan S; Pollard, Andrew; Wang, Chang (Elsevier, 2021-02-24)
    A wide array of biomaterials are being developed to be used as tissue engineering scaffolds, including metals, ceramics, polymers, and composites. For all biomaterials, the challenge remains to achieve functionality to mimic the biomechanical environment, induce bioactivity, and support critical size tissue reintegration. This calls for a functional evolution in biomaterials to be used as tissue engineering constructs for partial and full tissue reconstruction. When characterizing biomaterials for tissue engineering, the relevant extensions include engineered surfaces, micro-patterns, and porous architectures along with, bioactive, bioresorbable, and infection resistant properties. Accordingly, functional biomaterials will drive the next generation of tissue engineering constructs. This paper, therefore, explores the major concepts, future direction, and recent signs of progress in the field of tissue engineering biomaterials. Traditional materials are not discounted entirely as bioinert materials are still relevant and emerging research offers new functionalities for them to support drug, gene, and cell tissue engineering. Therefore, an attempt is also made to explain how the requirements of biomaterials are changing to facilitate, sustain, control, and proliferate engineered tissue. The article begins with a brief introduction to the evolution of biomaterials followed by a commentary on their functional requirements when applied to tissue engineering. This is followed by an exploratory evaluation of key tissue engineering constructs and their qualifiers while systematically identifying their future direction and potential.
  • First Report on the Geologic Occurrence of Natural Na–A Zeolite and Associated Minerals in Cretaceous Mudstones of the Paja Formation of Vélez (Santander), Colombia

    Ríos-Reyes, Carlos Alberto; Reyes-Mendoza, German Alfonso; Henao-Martínez, José Antonio; Williams, Craig; Dyer, Alan (MDPI, 2021-02-22)
    This study reports for the first time the geologic occurrence of natural zeolite A and associated minerals in mudstones from the Cretaceous Paja Formation in the urban area of the municipality of Vélez (Santander), Colombia. These rocks are mainly composed of quartz, muscovite, pyrophyllite, kaolinite and chlorite group minerals, framboidal and cubic pyrite, as well as marcasite, with minor feldspar, sulphates, and phosphates. Total organic carbon (TOC), total sulfur (TS), and millimeter fragments of algae are high, whereas few centimeters and not biodiverse small ammonite fossils, and other allochemical components are subordinated. Na–A zeolite and associated mineral phases as sodalite occur just beside the interparticle micropores (honeycomb from framboidal, cube molds, and amorphous cavities). It is facilitated by petrophysical properties alterations, due to processes of high diagenesis, temperatures up to 80–100 °C, with weathering contributions, which increase the porosity and permeability, as well as the transmissivity (fluid flow), allowing the geochemistry remobilization and/or recrystallization of pre-existing silica, muscovite, kaolinite minerals group, salts, carbonates, oxides and peroxides. X-ray diffraction analyses reveal the mineral composition of the mudstones and scanning electron micrographs show the typical cubic morphology of Na–A zeolite of approximately 0.45 mμ in particle size. Our data show that the sequence of the transformation of phases is: Poorly crystalline aluminosilicate → sodalite → Na–A zeolite. A literature review shows that this is an unusual example of the occurrence of natural zeolites in sedimentary marine rocks recognized around the world.
  • Minimum energy transmission forest-based Geocast in software-defined wireless sensor networks

    Banerjee, Anuradha; Sufian, Abu; Sadiq, Ali Safaa; Mirjalili, Seyedali (Wiley, 2021-12-31)
    Wireless Sensor Networks (WSNs)-based geographic addressing and routing have many potential applications. Geocast protocols should be made energy efficient to increase the lifetime of nodes and packet delivery ratio. This technique will increase the number of live nodes, reduce message costs, and enhance network throughput. All geocast protocols in the literature of WSN apply mostly restricted flooding and perimeter flooding, which is why still the redundancy they produce significantly high message transmission costs and unnecessarily eats up immense energy in nodes. Moreover, perimeter flooding cannot succeed in the presence of holes. The present article models wireless sensor networks with software-defined constructs where the network area is divided into some zones. Energy-efficient transmission tree(s) are constructed in the geocast area to organize the flow of data packets and their links. Therefore, redundancy in the transmission is eliminated while maintaining network throughput as good as regular flooding. This proposed technique significantly reduces energy cost and improves nodes' lifetime to function for higher time duration and produce a higher data packet delivery ratio. To the best of the author's knowledge, this is the first work on geocast in SD-WSNs.
  • Risk of COVID-19 hospital admission and COVID-19 mortality during the first COVID-19 wave with a special emphasis on ethnic minorities: an observational study of a single, deprived, multiethnic UK health economy

    Singh, Baldev M; Bateman, James; Viswanath, Ananth; Klaire, Vijay; Mahmud, Sultan; Nevill, Alan M; Dunmore, Simon J (BMJ, 2021-02-17)
    Objectives The objective of this study was to describe variations in COVID-19 outcomes in relation to local risks within a well-defined but diverse single-city area. Design Observational study of COVID-19 outcomes using quality-assured integrated data from a single UK hospital contextualised to its feeder population and associated factors (comorbidities, ethnicity, age, deprivation). Setting/participants Single-city hospital with a feeder population of 228 632 adults in Wolverhampton. Main outcome measures Hospital admissions (defined as COVID-19 admissions (CA) or non-COVID-19 admissions (NCA)) and mortality (defined as COVID-19 deaths or non-COVID-19 deaths). Results Of the 5558 patients admitted, 686 died (556 in hospital); 930 were CA, of which 270 were hospital COVID-19 deaths, 47 non-COVID-19 deaths and 36 deaths after discharge; of the 4628 NCA, there were 239 in-hospital deaths (2 COVID-19) and 94 deaths after discharge. Of the 223 074 adults not admitted, 407 died. Age, gender, multimorbidity and black ethnicity (OR 2.1 (95% CI 1.5 to 3.2), p<0.001, compared with white ethnicity, absolute excess risk of <1/1000) were associated with CA and mortality. The South Asian cohort had lower CA and NCA, lower mortality compared with the white group (CA, 0.5 (0.3 to 0.8), p<0.01; NCA, 0.4 (0.3 to 0.6), p<0.001) and community deaths (0.5 (0.3 to 0.7), p<0.001). Despite many common risk factors for CA and NCA, ethnic groups had different admission rates and within-group differing association of risk factors. Deprivation impacted only the white ethnicity, in the oldest age bracket and in a lesser (not most) deprived quintile. Conclusions Wolverhampton’s results, reflecting high ethnic diversity and deprivation, are similar to other studies of black ethnicity, age and comorbidity risk in COVID-19 but strikingly different in South Asians and for deprivation. Sequentially considering population and then hospital-based NCA and CA outcomes, we present a complete single health economy picture. Risk factors may differ within ethnic groups; our data may be more representative of communities with high Black, Asian and minority ethnic populations, highlighting the need for locally focused public health strategies. We emphasise the need for a more comprehensible and nuanced conveyance of risk.
  • Cyclodextrin diethyldithiocarbamate copper ii inclusion complexes: A promising chemotherapeutic delivery system against chemoresistant triple negative breast cancer cell lines

    Suliman, AS; Khoder, M; Tolaymat, I; Webster, M; Alany, RG; Wang, W; Elhissi, A; Najlah, M; Pharmaceutical Research Group, School of Allied Health, Faculty of Health, Education, Medicine and Social Care, Anglia Ruskin University, Bishops Hall Lane, Chelmsford CM1 1SQ, UK. (MDPI, 2021-01-10)
    Diethyldithiocarbamate Copper II (DDC-Cu) has shown potent anticancer activity against a wide range of cancer cells, but further investigations are hindered by its practical insolubility in water. In this study, inclusion complexes of DDC-Cu with hydroxypropyl beta-cyclodextrin (HP) or sulfobutyl ether beta-cyclodextrin (SBE) were prepared and investigated as an approach to enhance the apparent solubility of DDC-Cu. Formulations were prepared by simple mixing of DDC-Cu with both cyclodextrin (CDs) at room temperature. Phase solubility assessments of the resulting solutions were performed. DDC-Cu CD solutions were freeze-dried for further characterisations by DSC, thermogravimetric analysis (TGA) and FT-IR. Stability and cytotoxicity studies were also performed to investigate the maintenance of DDC-Cu anticancer activity. The phase solubility profile deviated positively from the linearity (Ap type) showing significant solubility enhancement of the DDC-Cu in both CD solutions (approximately 4 mg/mL at 20% w/w CD solutions). The DSC and TGA analysis confirmed the solid solution status of DDC-Cu in CD. The resulting solutions of DDC-Cu were stable for 28 days and conveyed the anticancer activity of DDC-Cu on chemoresistant triple negative breast cancer cell lines, with IC50 values less than 200 nM. Overall, cyclodextrin DDC-Cu complexes offer a great potential for anticancer applications, as evidenced by their very positive effects against chemoresistant triple negative breast cancer cells.
  • COVID-19 and construction law: comparing the United Kingdom and Australian response

    Charlson, Jennifer; Dickson, Rebecca (Informa Business Intelligence, 2021-12-31)
  • Which aspects of the open science agenda are most relevant to scientometric research and publishing? An opinion paper

    Bornmann, Lutz; Guns, Raf; Thelwall, Michael; Wolfram, Dietmar (MIT Press, 2021-02-10)
    Open Science is an umbrella term that encompasses many recommendations for possible changes in research practices, management, and publishing with the objective to increase transparency and accessibility. This has become an important science policy issue that all disciplines should consider. Many Open Science recommendations may be valuable for the further development of research and publishing but not all are relevant to all fields. This opinion paper considers the aspects of Open Science that are most relevant for scientometricians, discussing how they can be usefully applied.
  • Stability of planar switched systems under delayed event detection

    Legat, Benoit; Gomes, Claudio; Karalis, Paschalis; Jungers, Raphael M; Navarro-Lopez, Eva M; Vangheluwe, Hans (IEEE, 2021-01-11)
    In this paper, we analyse the impact of delayed event detection on the stability of a 2-mode planar hybrid automata. We consider hybrid automata with a unique equilibrium point for all the modes, and we find the maximum delay that preserves stability of that equilibrium point. We also show for the class of hybrid automata treated that the instability of the equilibrium point for the equivalent hybrid automaton with delay in the transitions is equivalent to the existence of a closed orbit in the hybrid state space, a result that is inspired by the Joint Spectral Radius theorem. This leads to an algorithm for computing the maximum stable delay exactly. Other potential applications of our technique include co-simulation, networked control systems and delayed controlled switching with a state feedback control.
  • The effects of micro- and macro- habitat variables on tent construction in the tent-roosting bat Artibeus watsoni on the Osa Peninsula, Costa Rica

    Brown, Scott; Kaburu, Stefano; Besenyei, Lynn (Museum and Institute of Zoology, Polish Academy of Sciences, 2021-12-31)
    Bats spend half of their lives in their roosts, which play vital roles in the life histories of the bats that occupy them. More than half of all bat species roost in foliage. Within the Neotropics, 17 species of bat are known to modify foliage into structures referred to as “tents”. Of these species, Thomas’s fruit eating bat (Artibeus watsoni) uses the widest range of plant species for roosts, constructing five different tent types. However, the factors influencing the distribution and quantity of tents are not fully understood for this species. The aims of our study were to investigate whether [1] micro-habitat characteristics influence the number of tents on individual plants and [2] macro-habitat features influence the frequency of plants used for tent-roosting in the surrounding landscape. Our results demonstrate that the distribution of tents was influenced by proximity to fresh water, with 48.8% of tents within 100 m of fresh water. Additionally, A. watsoni constructed tents in sheltered habitats with a high cover abundance of trees. These types of habitat areas should be targeted for conservation efforts to conserve this species.
  • Automated generation of hybrid automata for multi-rigid-body mechanical systems and its application to the falsification of safety properties

    Navarro-López, EM; O’Toole, MD (Taylor & Francis, 2017-08-29)
    What if we designed a tool to automatically generate a dynamical transition system for the formal specification of mechanical systems subject to multiple impacts, contacts and discontinuous friction? Such a tool would represent an advance in the description and simulation of these complex systems. This is precisely what this paper offers: Dyverse Rigid Body Toolbox (DyverseRBT). This tool requires a sufficiently expressive computational model that can accurately describe the behaviour of the system as it evolves over time. For this purpose, we propose an alternative abstraction of multi-rigid-body (MRB) mechanical systems with multiple contacts as an extended version of the classical hybrid automaton, which we call MRB hybrid automaton. One of the chief characteristics of the MRB hybrid automaton is the inclusion of computation nodes to encode algorithms to calculate the contact forces. The computation nodes consist of a set of non-dynamical discrete locations, discrete transitions and guards between these locations, and resets on transitions. They can account for the energy transfer not explicitly considered within the rigid-body formalism. The proposed modelling framework is well suited for the automated verification of dynamical properties of realistic mechanical systems. We show this by the falsification of safety properties over the transition system generated by DyverseRBT.
  • Deadness and how to disprove liveness in hybrid dynamical systems

    Navarro-López, EM; Carter, R (Elsevier, 2016-06-16)
    What if we designed a tool to automatically prove the dynamical properties of systems for which analytic proof is difficult or impossible to obtain? Such a tool would represent a significant advance in the understanding of complex dynamical systems with nonlinearities. This is precisely what this paper offers: a solution to the problem of automatically proving some dynamic stability properties of complex systems with multiple discontinuities and modes of operation modelled as hybrid dynamical systems. For this purpose, we propose a reinterpretation of some stability properties from a computational viewpoint, chiefly by using the computer science concepts of safety and liveness. However, these concepts need to be redefined within the framework of hybrid dynamical systems. In computer science terms, here, we consider the problem of automatically disproving the liveness properties of nonlinear hybrid dynamical systems. For this purpose, we define a new property, which we call deadness. This is a dynamically-aware property of a hybrid system which, if true, disproves the liveness property by means of a finite execution. We formally define this property, and give an algorithm which can derive deadness properties automatically for a type of liveness property called inevitability. We show how this algorithm works for three different examples that represent three classes of hybrid systems with complex behaviours.
  • Effects of scent enrichment on behavioural and physiological indicators of stress in zoo primates

    Vaglio, Stefano; Kaburu, Stefano; Pearce, Richard; Bryant, Luke; McAuley, Ailie; Lott, Alexandria; Sheppard, Demi; Smith, Sarah; Tompkins, Bethany; Elwell, Emily; et al. (Wiley, 2021-12-31)
    Captive breeding is vital for primate conservation, with modern zoos serving a crucial role in breeding populations of threatened species and educating the general public. However, captive populations can experience welfare issues that may also undermine their reproductive success. In order to enhance the well-being of endangered zoo primates, we conducted a study to assess the effects of a new scent enrichment programme on captive red-ruffed lemurs (Varecia rubra), black howler monkeys (Alouatta caraya), siamangs (Symphalangus syndactylus), Lar gibbons (Hylobates lar) and orangutans (Pongo pygmaeus pygmaeus). We combined behavioural observations and faecal endocrinology analyses to evaluate the effects of a series of essential oils (benzoin, lavender, lemongrass) on five captive troops (N = 19) housed at Dudley Zoo & Castle and Twycross Zoo (UK). We recorded observations of natural species-specific and abnormal stress-related behaviours for 480 hr using instantaneous scan sampling. We collected 189 faecal samples and measured the faecal cortisol concentrations using radioimmunoassay. We found a significant effect of the scent enrichment on behaviours, with red-ruffed lemurs and black howler monkeys reducing their social interactions, as well as red-ruffed lemurs and Lar gibbons decreasing their stress-related behaviours, after they were exposed to the series of essential oils. We also found that red-ruffed lemurs displayed a significant increase in faecal glucocorticoids following the exposure to essential oils. Our contradictory findings suggest that the effects of this series of essential oils may change depending on the species-specific social lives and olfactory repertoires of primates. In conclusion, we cannot recommend using these essential oils widely with zoo primates without additional evaluation.
  • The coevolution of sexual imprinting by males and females

    Gómez-Llano, Miguel Angel; Navarro-López, Eva María; Gilman, Robert Tucker (Wiley, 2016-09-14)
    Sexual imprinting is the learning of a mate preference by direct observation of the phenotype of another member of the population. Sexual imprinting can be paternal, maternal, or oblique if individuals learn to prefer the phenotypes of their fathers, mothers, or other members of the population, respectively. Which phenotypes are learned can affect trait evolution and speciation rates. “Good genes” models of polygynous systems predict that females should evolve to imprint on their fathers, because paternal imprinting helps females to choose mates that will produce offspring that are both viable and sexy. Sexual imprinting by males has been observed in nature, but a theory for the evolution of sexual imprinting by males does not exist. We developed a good genes model to study the conditions under which sexual imprinting by males or by both sexes can evolve and to ask which sexual imprinting strategies maximize the fitness of the choosy sex. We found that when only males imprint, maternal imprinting is the most advantageous strategy. When both sexes imprint, it is most advantageous for both sexes to use paternal imprinting. Previous theory suggests that, in a given population, either males or females but not both will evolve choosiness in mating. We show how environmental change can lead to the evolution of sexual imprinting behavior by both sexes in the same population.
  • Evolution of communities of software: using tensor decompositions to compare software ecosystems

    Blanthorn, Oliver A; Caine, Colin M; Navarro-López, Eva M (Springer Science and Business Media LLC, 2019-12-23)
    Modern software development is often a collaborative effort involving many authors through the re-use and sharing of code through software libraries. Modern software “ecosystems” are complex socio-technical systems which can be represented as a multilayer dynamic network. Many of these libraries and software packages are open-source and developed in the open on sites such as , so there is a large amount of data available about these networks. Studying these networks could be of interest to anyone choosing or designing a programming language. In this work, we use tensor factorisation to explore the dynamics of communities of software, and then compare these dynamics between languages on a dataset of approximately 1 million software projects. We hope to be able to inform the debate on software dependencies that has been recently re-ignited by the malicious takeover of the npm package and other incidents through giving a clearer picture of the structure of software dependency networks, and by exploring how the choices of language designers—for example, in the size of standard libraries, or the standards to which packages are held before admission to a language ecosystem is granted—may have shaped their language ecosystems. We establish that adjusted mutual information is a valid metric by which to assess the number of communities in a tensor decomposition and find that there are striking differences between the communities found across different software ecosystems and that communities do experience large and interpretable changes in activity over time. The differences between the elm and R software ecosystems, which see some communities decline over time, and the more conventional software ecosystems of Python, Java and JavaScript, which do not see many declining communities, are particularly marked.
  • Bioresorbable electrospun mats of poly(D, L)-lactide / poly[(R, S)-3-hydroxybutyrate] blends for potential use in the treatment of difficult-to-heal skin wounds

    Zięba, Magdalena; Włodarczyk, Jakub; Gupta, Abhishek; Pastusiak, Małgorzata; Chaber, Paweł; Janeczek, Henryk; Musioł, Marta; Sikorska, Wanda; Kaczmarczyk, Bożena; Radecka, Izabela; et al. (Elsevier, 2021-02-10)
    This study describes the preparation, physicochemical characterization and the biological studies of the polymeric delivery systems of proanthocyanidins (PCAN) extracted from Pelargonium sidoides for the potential use as wound dressings. In this study 20 wt% PCAN demonstrated good antimicrobial activity against Staphylococcus aures, a gram-positive wound pathogen. Poly(D,L-lactide) and atactic poly[(R,S)-3-hydroxybutyrate] biopolymers were used to construct biodegradable dressings. A series of polylactide/poly[(R,S)-3-hydroxybutyrate] (P(D,L)LA/a-PHB) blends, containing 10, 20, and 30 wt% of a-PHB were prepared and characterized by means of NMR, GPC, FT-IR, and DSC. Based on the findings, the P(D,L)LA/a-PHB [70/30 wt%] blend with the best thermomechanical properties (Tg value equal 37 °C) was chosen for the preparation of two kinds of electrospun mats, both with and without PCAN. About 50 % of PCAN was released from the tested mats during the first 10-12 days of incubation. The electrospun mats with elastic properties, ensuring compatibility with the wound topology, were obtained. The studies of hydrolytic degradation of the constructed mats allowed us to gain complete knowledge of their hydrolysis process, and examine the PCAN release profile as well as identify and characterize the molecular structure of the degradation products of the developed delivery system. Furthermore, preliminary cytotoxicity MTT tests (in vitro) results support the potential application of PCAN-loaded (P(D,L)LA/a-PHB) electrospun mats in wound dressings.
  • Structural response of cold-formed lipped Z purlins – Part 2 numerical modelling and optimisation of lip size

    Almatrafi, Meshal; Theofanous, Marios; Dirar, Samir; Bock, Marina (Elsevier, 2021-01-23)
    This paper reports a numerical study on the optimisation of the lip size of Z-sections under gravity loads. Numerical models of cold-formed steel Z purlins restrained by cladding and angle struts and subjected to sagging moment were developed and validated against a total of 8 experimental results on Z-sections that failed in local or/and distortional buckling reported in the companion paper. Models of varying levels of complexity were generated and the key parameters affecting the structural response were determined by means of a sensitivity analysis. The investigated parameters included the magnitude, shape and combination of initial geometric imperfections pertinent to local and distortional buckling and the simplified or explicit modelling of test details such as struts and sheeting. Having determined the appropriate modelling strategy that leads to the best balance between accuracy and computational cost, parametric studies were conducted to investigate the effect of decreasing or increasing the lip depth on the sections’ moment resistance and corresponding failure mode. Based on the parametric study results, the optimal lip size which maximizes the moment to weight ratio for each section was determined. Finally, all generated FE results are utilized to evaluate the accuracy of the moment resistance prediction of EN 1993-1-3 and the Direct Strength Method.
  • The introduction of brownfield land registers in England

    Charlson, Jennifer (Routledge, 2020-12-13)
    This review examines recent planning policy and legislation regarding the regeneration of brownfield land in England. The study is centred on housing and England’s West Midlands region with a focus on the Black Country. The Housing and Planning Act 2016 introduced provisions to grant permission in principle for housing-led development in England and mandated the assembly of brownfield planning registers. The Brownfield Land Register Regulations 2017 requirements and their implementation is explored. The review concludes that of almost 18,000 brownfield sites have been mapped and capacity for 1.3 million homes on 21,000 sites covering 25,000 hectares has been identified on brownfield registers.

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