Azithromycin therapy for prevention of chronic lung disease of prematurity (AZTEC): a multicentre, double-blind, randomised, placebo-controlled trial.

BACKGROUND: Systematic reviews have reported conflicting evidence on whether macrolide antibiotics reduce rates of chronic lung disease of prematurity (CLD) in at-risk preterm infants born at less than 30 weeks' gestation, including in those colonised with pulmonary Ureaplasma spp. Since an adequately powered trial has been lacking, we aimed to assess if the macrolide azithromycin improved survival without the development of physiologically defined moderate or severe CLD in preterm infants. METHODS: AZTEC was a multicentre, double-blind, randomised, placebo-controlled trial conducted in 28 tertiary neonatal intensive care units in the UK. Infants were eligible if they were born at less than 30 weeks' gestation and had received at least 2 h of either non-invasive (continuous positive airway pressure or humidified high flow nasal cannula therapy) or invasive respiratory support (via endotracheal tube) within 72 h of birth. Eligible infants were randomly allocated in a 1:1 ratio using random permuted blocks of four to receive either intravenous azithromycin at 20 mg/kg per day for 3 days followed by 10 mg/kg for 7 days, or to placebo. Allocation was stratified by centre and gestational age at birth (<28 weeks vs ≥28 weeks). Azithromycin and placebo vials were encased in tamper-evident custom cardboard cartons to ensure masking for clinicians, parents, and the research team. The primary outcome was survival without development of physiologically defined moderate or severe CLD at 36 weeks' postmenstrual age. Outcomes and safety were analysed on an intention-to-treat basis (all randomly allocated infants, regardless of any post-randomisation events). The study was registered with ISRCRN (11650227) and is closed. FINDINGS: Infants were recruited between Oct 9, 2019, and March 22, 2022. 799 (53·1%) of 1505 eligible infants underwent random allocation; three infants were withdrawn, including consent to use their data, leaving 796 infants for analysis. Survival without moderate or severe CLD occurred in 166 (42%) of 394 infants in the intervention group and 179 (45%) of 402 in the placebo group (three-level adjusted OR [aOR] 0·84, 95% CI 0·55-1·29, p=0·43). Pulmonary Ureaplasma spp colonisation did not influence treatment effect. Overall, seven serious adverse events were reported for the azithromycin group (five graded as severe, two as moderate), and six serious adverse events were reported in the placebo group (two severe, two moderate, and two mild), as assessed by the local principal investigators. INTERPRETATION: Since prophylactic use of azithromycin did not improve survival without development of physiologically-defined CLD, regardless of Ureaplasma spp colonisation, it cannot be recommended in clinical practice. FUNDING: UK National Institute for Health and Care Research.

Satisfaction with remote consultations in primary care during COVID-19: a population survey of UK adults.

BACKGROUND: Mode of access to primary care changed during the COVID-19 pandemic; remote consultations became more widespread. With remote consultations likely to continue in UK primary care, it is important to understand people's perceptions of remote consultations and identify potential resulting inequalities. AIM: To assess satisfaction with remote GP consultations in the UK during the COVID-19 pandemic and identify demographic variation in satisfaction levels. DESIGN AND SETTING: A cross-sectional survey from the second phase of a large UK-based study, which was conducted during the COVID-19 pandemic. METHOD: In total, 1426 adults who self-reported having sought help from their doctor in the past 6 months completed an online questionnaire (February to March 2021). Items included satisfaction with remote consultations and demographic variables. Associations were analysed using multivariable regression. RESULTS: A novel six-item scale of satisfaction with remote GP consultations had good psychometric properties. Participants with higher levels of education had significantly greater satisfaction with remote consultations than participants with mid-level qualifications (B = -0.82, 95% confidence interval [CI] = -1.41 to -0.23) or those with low or no qualifications (B = -1.65, 95% CI = -2.29 to -1.02). People living in Wales reported significantly higher satisfaction compared with those living in Scotland (B = -1.94, 95% CI = -3.11 to -0.78), although caution is warranted due to small group numbers. CONCLUSION: These findings can inform the use and adaptation of remote consultations in primary care. Adults with lower educational levels may need additional support to improve their experience and ensure equitable care via remote consultations.

Health behaviour change among UK adults during the pandemic: findings from the COVID-19 cancer attitudes and behaviours study.

BACKGROUND: COVID-19 related lockdowns may have affected engagement in health behaviours among the UK adult population. This prospective observational study assessed socio-demographic patterning in attempts to change and maintain a range of health behaviours and changes between two time points during the pandemic. METHODS: Adults aged 18 years and over (n = 4,978) were recruited using Dynata (an online market research platform) and the HealthWise Wales platform, supplemented through social media advertising. Online surveys were conducted in August/September 2020 when lockdown restrictions eased in the UK following the first major UK lockdown (survey phase 1) and in February/March 2021 during a further national lockdown (survey phase 2). Measures derived from the Cancer Awareness Measure included self-reported attempts to reduce alcohol consumption, increase fruit/vegetable consumption, increase physical activity, lose weight and reduce/stop smoking. Multivariable logistic regressions were used to assess individual health behaviour change attempts over time, adjusted for age, sex, ethnicity, employment and education. RESULTS: Around half of participants in survey phase 1 reported trying to increase physical activity (n = 2607, 52.4%), increase fruit/vegetables (n = 2445, 49.1%) and lose weight (n = 2413, 48.5%), with 19.0% (n = 948) trying to reduce alcohol consumption among people who drink. Among the 738 participants who smoked, 51.5% (n = 380) were trying to reduce and 27.4% (n = 202) to stop smoking completely. Most behaviour change attempts were more common among women, younger adults and minority ethnic group participants. Efforts to reduce smoking (aOR: 0.98, 95% CI: 0.82-1.17) and stop smoking (aOR: 0.98, 95% CI: 0.80-1.20) did not differ significantly in phase 2 compared to phase 1. Similarly, changes over time in attempts to improve other health behaviours were not statistically significant: physical activity (aOR: 1.07; 95% CI: 0.99-1.16); weight loss (aOR: 0.95; 95% CI: 0.90-1.00); fruit/vegetable intake (aOR: 0.98, 95% CI: 0.91-1.06) and alcohol use (aOR: 1.32, 95% CI: 0.92-1.91). CONCLUSION: A substantial proportion of participants reported attempts to change health behaviours in the initial survey phase. However, the lack of change observed over time indicated that overall motivation to engage in healthy behaviours was sustained among the UK adult population, from a period shortly after the first lockdown toward the end of the second prolonged lockdown.

Can biodiverse streetscapes mitigate the effects of noise and air pollution on human wellbeing?

Most of the global population are urban, with inhabitants exposed to raised levels of pollution. Pollutants negatively impact human wellbeing, and can alter the structure and diversity of ecosystems. Contrastingly, urban biodiversity can positively contribute to human wellbeing. We know little, however, about whether the negative impacts of pollution on wellbeing could be lessened for householders living on more biodiverse streets, as the complex interlinkages between pollution, biodiversity and wellbeing have rarely been examined. Here, we used structural equation modelling to simultaneously test whether biodiversity (actual and perceived) mediates the relationship between traffic-related pollution (noise, dB; nitrogen dioxide, NO2) or air pollution (PM2.5) and wellbeing (mental wellbeing, happiness). In summer 2019, we conducted questionnaires and biodiversity surveys, and collected noise and air pollution data, from households (n = 282) across the streetscapes of Leeds, UK. Biodiversity (actual or perceived) showed no mediating effects. However, increased flowering plant richness was positively associated with mental wellbeing. Traffic-related pollution negatively affected pollinator and flowering plant richness, but not wellbeing. This could be because householders are not exposed to high levels of noise or NO2 because they do not maintain front gardens on noisier streets. There was no measurable effect of air pollution on biodiversity or wellbeing. These findings shed light on the complex mechanisms through which biodiversity could improve human wellbeing. Enhancing the diversity of plant species in streetscapes would have a positive effect on wellbeing, further emphasising the important role that biodiverse urban streetscapes play in improving the liveability of cities.

The READ-IT study protocol for a feasibility randomised controlled trial of using a support worker/family carer mediated online reading programme to teach early reading skills to adults with intellectual disabilities.

BACKGROUND: Many individuals with intellectual disability (ID) have not learnt basic reading skills by the time that they reach adulthood, potentially limiting their access to critical information. READ-IT is an online reading programme developed from the Headsprout® Early Reading (HER®) intervention and supplemented by support strategies tailored for adults with ID. HER® has been successfully used to teach adults with ID to read in a forensic setting by trained staff. The aim of this study is to assess the feasibility of delivering READ-IT to adults with ID by family carers/support workers and will assess whether it would be feasible to conduct a later definitive randomised controlled trial (RCT) of the effectiveness of the programme. The study will aim to contribute to the evidence base on improving outcomes for adults with ID and their caregivers. METHODS: This study is a feasibility RCT, with embedded process evaluation. Forty-eight adults with ID will be recruited and allocated to intervention: control on a 1:1 basis. Intervention families will be offered the READ-IT programme immediately, continuing to receive usual practice and control participants will be offered the opportunity to receive READ-IT at the end of the trial follow-up period and will continue to receive usual practice. Data will be collected at baseline and 6 months post-randomisation. DISCUSSION: The results of this study will inform a potential future definitive trial, to evaluate the effectiveness of READ-IT to improve reading skills. Such a trial would have significant scientific impact internationally in the intellectual disability field. TRIAL REGISTRATION: ISRCTN11409097.

Intentions to participate in cervical and colorectal cancer screening during the COVID-19 pandemic: A mixed-methods study.

Worldwide, cancer screening faced significant disruption in 2020 due to the COVID-19 pandemic. If this has led to changes in public attitudes towards screening and reduced intention to participate, there is a risk of long-term adverse impact on cancer outcomes. In this study, we examined previous participation and future intentions to take part in cervical and colorectal cancer (CRC) screening following the first national lockdown in the UK. Overall, 7543 adults were recruited to a cross-sectional online survey in August-September 2020. Logistic regression analyses were used to identify correlates of strong screening intentions among 2319 participants eligible for cervical screening and 2502 eligible for home-based CRC screening. Qualitative interviews were conducted with a sub-sample of 30 participants. Verbatim transcripts were analysed thematically. Of those eligible, 74% of survey participants intended to attend cervical screening and 84% intended to complete home-based CRC screening when next invited. Thirty percent and 19% of the cervical and CRC samples respectively said they were less likely to attend a cancer screening appointment now than before the pandemic. Previous non-participation was the strongest predictor of low intentions for cervical (aOR 26.31, 95% CI: 17.61-39.30) and CRC (aOR 67.68, 95% CI: 33.91-135.06) screening. Interview participants expressed concerns about visiting healthcare settings but were keen to participate when screening programmes resumed. Intentions to participate in future screening were high and strongly associated with previous engagement in both programmes. As screening services recover, it will be important to monitor participation and to ensure people feel safe to attend.

Cancer symptom experience and help-seeking behaviour during the COVID-19 pandemic in the UK: a cross-sectional population survey.

OBJECTIVES: To understand self-reported potential cancer symptom help-seeking behaviours and attitudes during the first 6 months (March-August 2020) of the UK COVID-19 pandemic. DESIGN: UK population-based survey conducted during August and September 2020. Correlates of help-seeking behaviour were modelled using logistic regression in participants reporting potential cancer symptoms during the previous 6 months. Qualitative telephone interviews with a purposeful subsample of participants, analysed thematically. SETTING: Online UK wide survey. PARTICIPANTS: 7543 adults recruited via Cancer Research UK online panel provider (Dynata) and HealthWise Wales (a national register of 'research ready' participants) supplemented with social media (Facebook and Twitter) recruitment. 30 participants were also interviewed. MAIN OUTCOME MEASURES: Survey measures included experiences of 15 potential cancer symptoms, help-seeking behaviour, barriers and prompts to help-seeking. RESULTS: Of 3025 (40.1%) participants who experienced a potential cancer symptom, 44.8% (1355/3025) had not contacted their general practitioner (GP). Odds of help-seeking were higher among participants with disability (adjusted OR (aOR)=1.38, 95% CI 1.11 to 1.71) and who experienced more symptoms (aOR=1.68, 95% CI 1.56 to 1.82), and lower among those who perceived COVID-19 as the cause of symptom(s) (aOR=0.36, 95% CI 0.25 to 0.52). Barriers included worries about wasting the doctor's time (1158/7543, 15.4%), putting strain on healthcare services (945, 12.6%) and not wanting to make a fuss (907, 12.0%). Interviewees reported reluctance to contact the GP due to concerns about COVID-19 and fear of attending hospitals, and described putting their health concerns on hold. CONCLUSIONS: Many people avoided healthcare services despite experiencing potential cancer symptoms during the COVID-19 pandemic. Alongside current help-seeking campaigns, well-timed and appropriate nationally coordinated campaigns should signal that services are open safely for those with unusual or persistent symptoms. TRIAL REGISTRATION NUMBER: ISRCTN17782018.

A global horizon scan of the future impacts of robotics and autonomous systems on urban ecosystems.

Technology is transforming societies worldwide. A major innovation is the emergence of robotics and autonomous systems (RAS), which have the potential to revolutionize cities for both people and nature. Nonetheless, the opportunities and challenges associated with RAS for urban ecosystems have yet to be considered systematically. Here, we report the findings of an online horizon scan involving 170 expert participants from 35 countries. We conclude that RAS are likely to transform land use, transport systems and human-nature interactions. The prioritized opportunities were primarily centred on the deployment of RAS for the monitoring and management of biodiversity and ecosystems. Fewer challenges were prioritized. Those that were emphasized concerns surrounding waste from unrecovered RAS, and the quality and interpretation of RAS-collected data. Although the future impacts of RAS for urban ecosystems are difficult to predict, examining potentially important developments early is essential if we are to avoid detrimental consequences but fully realize the benefits.

Passive CO2 removal in urban soils: Evidence from brownfield sites.

Management of urban brownfield land can contribute to significant removal of atmospheric CO2 through the development of soil carbonate minerals. However, the potential magnitude and stability of this carbon sink is poorly quantified as previous studies address a limited range of conditions and short durations. Furthermore, the suitability of carbonate-sequestering soils for construction has not been investigated. To address these issues we measured total inorganic carbon, permeability and ground strength in the top 20 cm of soil at 20 brownfield sites in northern England, between 2015 and 2017. Across all sites accumulation occurred at a rate of 1-16 t C ha-1 yr-1, as calcite (CaCO3), corresponding to removal of approximately 4-59 t CO2 ha-1 yr-1, with the highest rate in the first 15 years after demolition. C and O stable isotope analysis of calcite confirms the atmospheric origin of the measured inorganic carbon. Statistical modelling found that pH and the content of fine materials (combined silt and clay content) were the best predictors of the total inorganic carbon content of the samples. Measurement of permeability shows that sites with carbonated soils possess a similar risk of run-off or flooding to sandy soils. Soil strength, measured as in-situ bearing capacity, increased with carbonation. These results demonstrate that the management of urban brownfield land to retain fine material derived from concrete crushing on site following demolition will promote calcite precipitation in soils, and so offers an additional CO2 removal mechanism, with no detrimental effect on drainage and possible improvements in strength. Given the large area of brownfield land that is available for development, the contribution of this process to CO2 removal by urban soils needs to be recognised in CO2 mitigation policies.

A systems approach reveals urban pollinator hotspots and conservation opportunities.

Urban areas are often perceived to have lower biodiversity than the wider countryside, but a few small-scale studies suggest that some urban land uses can support substantial pollinator populations. We present a large-scale, well-replicated study of floral resources and pollinators in 360 sites incorporating all major land uses in four British cities. Using a systems approach, we developed Bayesian network models integrating pollinator dispersal and resource switching to estimate city-scale effects of management interventions on plant-pollinator community robustness to species loss. We show that residential gardens and allotments (community gardens) are pollinator 'hotspots': gardens due to their extensive area, and allotments due to their high pollinator diversity and leverage on city-scale plant-pollinator community robustness. Household income was positively associated with pollinator abundance in gardens, highlighting the influence of socioeconomic factors. Our results underpin urban planning recommendations to enhance pollinator conservation, using increasing city-scale community robustness as our measure of success.

Adaptive response of neonatal sepsis-derived Group B Streptococcus to bilirubin.

Hyperbilirubinemia is so common in newborns as to be termed physiological. The most common bacteria involved in early-onset neonatal sepsis are Streptococcus agalactiae, commonly called Group B Streptococcus (GBS). Whilst previous studies show bilirubin has antioxidant properties and is beneficial in endotoxic shock, little thought has been given to whether bilirubin might have antibacterial properties. In this study, we performed a transcriptomic and proteomic assessment of GBS cultured in the presence/absence of bilirubin. Our analysis revealed that increasing levels of bilirubin (>100 µmol/L) negatively correlated with GBS growth (18% reduction from 0-400 µmol/L on plate model, p < 0.001; 33% reduction from 0-100 µmol/L in liquid model, p = 0.02). Transcriptome analysis demonstrated 19 differentially expressed genes, almost exclusively up-regulated in the presence of bilirubin. Proteomic analysis identified 12 differentially expressed proteins, half over-expressed in the presence of bilirubin. Functional analysis using Gene Ontology and KEGG pathways18 revealed a differential expression of genes involved in transport and carbohydrate metabolism, suggesting bilirubin may impact on substrate utilisation. The data improve our understanding of the mechanisms modulating GBS survival in neonatal hyperbilirubinemia and suggest physiological jaundice may have an evolutionary role in protection against early-onset neonatal sepsis.

Beyond Ecosystem Services: Valuing the Invaluable.

The ecosystem services framework (ESF) is advantageous and widely used for itemising and quantifying ways in which humans benefit from natural places. However, it suffers from two important problems: (i) incoherence of definitions and (ii) a narrow approach to valuation, inadequate to represent the full range of human motives for conservation and the diverse interests of different stakeholders. These shortcomings can lead to a range of problems including double-counting, blind spots and unintended consequences. In this opinion article, we propose an ecosystem valuing framework as a broader and more rigorous way to deliver the benefits currently sought from the ESF, without the conceptual problems.

Molecular taxonomic analysis of the plant associations of adult pollen beetles (Nitidulidae: Meligethinae), and the population structure of Brassicogethes aeneus.

Pollen beetles (Nitidulidae: Meligethinae) are among the most abundant flower-visiting insects in Europe. While some species damage millions of hectares of crops annually, the biology of many species is little known. We assessed the utility of a 797 base pair fragment of the cytochrome oxidase 1 gene to resolve molecular operational taxonomic units (MOTUs) in 750 adult pollen beetles sampled from flowers of 63 plant species sampled across the UK and continental Europe. We used the same locus to analyse region-scale patterns in population structure and demography in an economically important pest, Brassicogethes aeneus. We identified 44 Meligethinae at ∼2% divergence, 35 of which contained published sequences. A few specimens could not be identified because the MOTUs containing them included published sequences for multiple Linnaean species, suggesting either retention of ancestral haplotype polymorphism or identification errors in published sequences. Over 90% of UK specimens were identifiable as B. aeneus. Plant associations of adult B. aeneus were found to be far wider taxonomically than for their larvae. UK B. aeneus populations showed contrasting affiliations between the north (most similar to Scandinavia and the Baltic) and south (most similar to western continental Europe), with strong signatures of population growth in the south.

Hierarchical filters determine community assembly of urban species pools.

The majority of humanity now lives in cities or towns, with this proportion expected to continue increasing for the foreseeable future. As novel ecosystems, urban areas offer an ideal opportunity to examine multi-scalar processes involved in community assembly as well as the role of human activities in modulating environmental drivers of biodiversity. Although ecologists have made great strides in recent decades at documenting ecological relationships in urban areas, much remains unknown, and we still need to identify the major ecological factors, aside from habitat loss, behind the persistence or extinction of species and guilds of species in cities. Given this paucity of knowledge, there is an immediate need to facilitate collaborative, interdisciplinary research on the patterns and drivers of biodiversity in cities at multiple spatial scales. In this review, we introduce a new conceptual framework for understanding the filtering processes that mold diversity of urban floras and faunas. We hypothesize that the following hierarchical series of filters influence species distributions in cities: (1) regional climatic and biogeographical factors; (2) human facilitation; (3) urban form and development history; (4) socioeconomic and cultural factors; and (5) species interactions. In addition to these filters, life history and functional traits of species are important in determining community assembly and act at multiple spatial scales. Using these filters as a conceptual framework can help frame future research needed to elucidate processes of community assembly in urban areas. Understanding how humans influence community structure and processes will aid in the management, design, and planning of our cities to best support biodiversity.

Food for Pollinators: Quantifying the Nectar and Pollen Resources of Urban Flower Meadows.

Planted meadows are increasingly used to improve the biodiversity and aesthetic amenity value of urban areas. Although many 'pollinator-friendly' seed mixes are available, the floral resources these provide to flower-visiting insects, and how these change through time, are largely unknown. Such data are necessary to compare the resources provided by alternative meadow seed mixes to each other and to other flowering habitats. We used quantitative surveys of over 2 million flowers to estimate the nectar and pollen resources offered by two exemplar commercial seed mixes (one annual, one perennial) and associated weeds grown as 300m2 meadows across four UK cities, sampled at six time points between May and September 2013. Nectar sugar and pollen rewards per flower varied widely across 65 species surveyed, with native British weed species (including dandelion, Taraxacum agg.) contributing the top five nectar producers and two of the top ten pollen producers. Seed mix species yielding the highest rewards per flower included Leontodon hispidus, Centaurea cyanus and C. nigra for nectar, and Papaver rhoeas, Eschscholzia californica and Malva moschata for pollen. Perennial meadows produced up to 20x more nectar and up to 6x more pollen than annual meadows, which in turn produced far more than amenity grassland controls. Perennial meadows produced resources earlier in the year than annual meadows, but both seed mixes delivered very low resource levels early in the year and these were provided almost entirely by native weeds. Pollen volume per flower is well predicted statistically by floral morphology, and nectar sugar mass and pollen volume per unit area are correlated with flower counts, raising the possibility that resource levels can be estimated for species or habitats where they cannot be measured directly. Our approach does not incorporate resource quality information (for example, pollen protein or essential amino acid content), but can easily do so when suitable data exist. Our approach should inform the design of new seed mixes to ensure continuity in floral resource availability throughout the year, and to identify suitable species to fill resource gaps in established mixes.

Where is the UK's pollinator biodiversity? The importance of urban areas for flower-visiting insects.

Insect pollinators provide a crucial ecosystem service, but are under threat. Urban areas could be important for pollinators, though their value relative to other habitats is poorly known. We compared pollinator communities using quantified flower-visitation networks in 36 sites (each 1 km(2)) in three landscapes: urban, farmland and nature reserves. Overall, flower-visitor abundance and species richness did not differ significantly between the three landscape types. Bee abundance did not differ between landscapes, but bee species richness was higher in urban areas than farmland. Hoverfly abundance was higher in farmland and nature reserves than urban sites, but species richness did not differ significantly. While urban pollinator assemblages were more homogeneous across space than those in farmland or nature reserves, there was no significant difference in the numbers of rarer species between the three landscapes. Network-level specialization was higher in farmland than urban sites. Relative to other habitats, urban visitors foraged from a greater number of plant species (higher generality) but also visited a lower proportion of available plant species (higher specialization), both possibly driven by higher urban plant richness. Urban areas are growing, and improving their value for pollinators should be part of any national strategy to conserve and restore pollinators.

Lactic acidosis after cardiac transplantation: foe or common innocent bystander?

BACKGROUND: Lactic acidosis (LA) frequently occurs after heart transplantation (HTx). It is hypothesized to be related to inotropic support or metabolic derangements from chronic heart failure. As such, restoring hemodynamic stability with mechanical circulatory support before HTx should mitigate this problem. Our aim was to evaluate the incidence and outcomes of LA after HTx. METHODS: We evaluated HTx recipients January 2000 to May 2011. Post-HTx outcomes included graft dysfunction, length of intensive care unit stay, length of hospital stay, inotropic support, and survival. RESULTS: Of 143 eligible patients, 98.6% had LA, 67% severe, after HTx. Data were analyzed based on the severity of LA. Time to peak lactate, intensive care unit stay, length of hospital stay, peak glucose, inotropic dose, graft dysfunction, and survival after HTx were similar between groups. Statistically significant differences included pretransplant support (25.6% mechanical circulatory support in nonsevere vs. 44.9% severe LA), hospitalization at the time of HTx (37.2% vs. 21.4%), glucose at the time of peak lactate (182.88 ± 69.80 vs. 221.31 ± 56.91), ischemic time (187.4 ± 63.1 vs. 215.5 ± 68.1), and duration of inotrope. CONCLUSION: Severe LA is common after HTx, though it appears to be transient and benign. Mechanical circulatory support after HTx does not prevent LA. High lactate levels are associated with longer ischemic times, longer duration of inotrope, and correspond with higher glucose levels. The underlying mechanism is yet to be satisfactorily elucidated.

A global analysis of the impacts of urbanization on bird and plant diversity reveals key anthropogenic drivers.

Urbanization contributes to the loss of the world's biodiversity and the homogenization of its biota. However, comparative studies of urban biodiversity leading to robust generalities of the status and drivers of biodiversity in cities at the global scale are lacking. Here, we compiled the largest global dataset to date of two diverse taxa in cities: birds (54 cities) and plants (110 cities). We found that the majority of urban bird and plant species are native in the world's cities. Few plants and birds are cosmopolitan, the most common being Columba livia and Poa annua. The density of bird and plant species (the number of species per km(2)) has declined substantially: only 8% of native bird and 25% of native plant species are currently present compared with estimates of non-urban density of species. The current density of species in cities and the loss in density of species was best explained by anthropogenic features (landcover, city age) rather than by non-anthropogenic factors (geography, climate, topography). As urbanization continues to expand, efforts directed towards the conservation of intact vegetation within urban landscapes could support higher concentrations of both bird and plant species. Despite declines in the density of species, cities still retain endemic native species, thus providing opportunities for regional and global biodiversity conservation, restoration and education.

Scaling up from gardens: biodiversity conservation in urban environments.

As urbanisation increases globally and the natural environment becomes increasingly fragmented, the importance of urban green spaces for biodiversity conservation grows. In many countries, private gardens are a major component of urban green space and can provide considerable biodiversity benefits. Gardens and adjacent habitats form interconnected networks and a landscape ecology framework is necessary to understand the relationship between the spatial configuration of garden patches and their constituent biodiversity. A scale-dependent tension is apparent in garden management, whereby the individual garden is much smaller than the unit of management needed to retain viable populations. To overcome this, here we suggest mechanisms for encouraging 'wildlife-friendly' management of collections of gardens across scales from the neighbourhood to the city.