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Global land cover (LC) changes threaten sustainability and yet we lack a comprehensive understanding of the gains and losses of LC types, including the magnitudes, locations and timings of transitions. We used a novel, fine-resolution and temporally consistent satellite-derived dataset covering the entire Earth annually from 1992 to 2018 to quantify LC changes across a range of scales. At global and continental scales, the observed trajectories of change for most LC types were fairly smooth and consistent in direction through time. We show these observed trajectories in the context of error margins produced by extrapolating previously published accuracy metrics associated with the LC dataset. For many LC classes the observed changes were found to be within the error margins. However, an important exception was the increase in urban land, which was consistently larger than the error margins, and for which the LC transition was unidirectional. An advantage of analysing the global, fine spatial resolution LC time-series dataset is the ability to identify where and when LC changes have taken place on the Earth. We present LC change maps and trajectories that identify locations with high dynamism, and which pose significant sustainability challenges. We focused on forest loss and urban growth at the national scale, identifying the top 10 countries with the largest percentages of forest loss and urban growth globally. Crucially, we found that most of these ‘worst-case’ countries have stabilized their forest losses, although urban expansion was monotonic in all cases. These findings provide crucial information to support progress towards the UN’s SDGs.

Egypt has one of the largest and fastest growing populations in the world. However, nearly 96% of the total land area is uninhabited desert and 96% of the population is concentrated around the River Nile valley and the Delta. This unbalanced distribution and dramatically rising population have caused severe socio-economic problems. In this research, 24 land use/land cover (LULC) maps from 1992 to 2015 were used to monitor LULC changes in the Nile Delta and quantify the rates and types of LULC transitions. The results show that 74,600 hectares of fertile agricultural land in the Nile Delta (Old Lands) was lost to urban expansion over the 24 year period at an average rate of 3108 ha year−1, whilst 206,100 hectares of bare land was converted to agricultural land (New Lands) at an average rate of 8588 ha year−1. A Cellular Automata-Markov (CA-Markov) integrated model was used to simulate future alternative LULC change scenarios. Under a Business as Usual scenario, 87,000 hectares of land transitioned from agricultural land to urban areas by 2030, posing a threat to the agricultural sector sustainability and food security in Egypt. Three alternative future scenarios were developed to promote urban development elsewhere, hence, with potential to preserve the fertile soils of the Nile Delta. A scenario which permitted urban expansion into the desert only preserved the largest amount of agricultural land in the Nile Delta. However, a scenario that encouraged urban expansion into the desert and adjacent to areas of existing high population density resulted in almost the same area of agricultural land being preserved. The alternative future scenarios are valuable for supporting policy development and planning decisions in Egypt and demonstrating that continued urban development is possible while minimising the threats to environmental sustainability and national food security.

The plant trait composition of forest fragments is thought to be partly determined by forest spatial properties, although the relative importance of habitat configuration and local abiotic drivers is poorly understood. To address this issue, large‐scale habitat extent data were combined with detailed field survey information for temperate broad‐leaved deciduous forest patches to quantify the relative effects of spatial and abiotic filters on plant community mean trait values. Local conditions such as shade and soil fertility had the largest effect on mean trait values, but aspects of habitat configuration also had significant partial effects on a number of traits. Mean trait values within older forest patches were more strongly influenced by forest spatial configuration than in younger patches. Synthesis. Results indicate that, in addition to the effects of greater light availability and competition in small patches and at forest edges, aspects of habitat configuration such as patch size and isolation are themselves important factors limiting the occurrence of forest specialist species. Large areas of core forest habitat contain a greater proportion of rare, poor dispersing species, although these effects were less visible in more recently established forest. This highlights the importance of maintaining existing large and old forest patches as a refuge for forest specialist plants. The results of this comparison of spatial and abiotic variables suggest that controlling the spatial properties of forest patches is likely to prove an effective way of managing plant species diversity, provided that sites with appropriate abiotic conditions are chosen.

There is increasing evidence to suggest that a delayed response of many forest species to habitat loss and fragmentation leads to the development of extinction debts and immigration credits in affected forest habitat. These time lags result in plant communities which are not well predicted by present day landscape structure, reducing the accuracy of biodiversity assessments and predictions for future change. Here, species richness data and mean values for five life history characteristics within deciduous broadleaved forest habitat across Great Britain were used to quantify the degree to which aspects of present day forest plant composition are best explained by modern or historical forest patch area. Ancient forest specialist richness, mean rarity and mean seed terminal velocity were not well predicted by modern patch area, implying the existence of a degree of lag in British forest patches. Mean seedbank persistence values were more closely related to modern patch area than historical, particularly in larger patches. The variation in response for different mean trait values suggests that species respond to landscape change at different rates depending upon their combinations of different trait states. Current forest understorey communities are therefore likely to consist of a mixture of declining species whose extinction debt is still to be paid, and faster colonising immigrant species. These results indicate that without management action, rare and threatened species of plant are likely to be lost in the future as a result of changes in forest spatial configuration that have already taken place. The lag seen here for rare specialist plants suggests however that there may still be scope to protect such species before they are lost from forest patches.

The dynamics of pigment concentrations are diagnostic of a range of plant physiological properties and processes. This paper appraises the developing technologies and analytical methods for quantifying pigments non-destructively and repeatedly across a range of spatial scales using hyperspectral remote sensing. Progress in deriving predictive relationships between various characteristics and transforms of hyperspectral reflectance data are evaluated and the roles of leaf and canopy radiative transfer models are reviewed. Requirements are identified for more extensive intercomparisons of different approaches and for further work on the strategies for interpreting canopy scale data. The paper examines the prospects for extending research to the wider range of pigments in addition to chlorophyll, testing emerging methods of hyperspectral analysis and exploring the fusion of hyperspectral and LIDAR remote sensing. In spite of these opportunities for further development and the refinement of techniques, current evidence of an expanding range of applications in the ecophysiological, environmental, agricultural, and forestry sciences highlights the growing value of hyperspectral remote sensing of plant pigments.

The worldwide spread of H5N1 avian influenza has raised concerns that this virus might acquire the ability to pass readily among humans and cause a pandemic. Two anti-influenza drugs currently being used to treat infected patients are oseltamivir (Tamiflu) and zanamivir (Relenza), both of which target the neuraminidase enzyme of the virus. Reports of the emergence of drug resistance make the development of new anti-influenza molecules a priority. Neuraminidases from influenza type A viruses form two genetically distinct groups: group-1 contains the N1 neuraminidase of the H5N1 avian virus and group-2 contains the N2 and N9 enzymes used for the structure-based design of current drugs. Here we show by X-ray crystallography that these two groups are structurally distinct. Group-1 neuraminidases contain a cavity adjacent to their active sites that closes on ligand binding. Our analysis suggests that it may be possible to exploit the size and location of the group-1 cavity to develop new anti-influenza drugs. Tackling the H5N1 virus H5N1 avian flu virus is so named from the haemagglutinin (H) and neuraminidase (N) proteins on the virus coat; each protein comes in several different forms. Neuraminidase helps the virus to escape infected cells and attack new ones, and is targeted by Tamiflu (oseltamivir) and Relenza (zanamivir). These drugs were designed on the basis of the crystal structures for neuraminidases N2 and N9 — the only such structures then available. Now the structures of N1, N4 and N8 have been determined. They share a key difference when compared with the previous structures: a cavity in a corner of the active site that closes to lock onto its target. It may be possible to exploit this structure with drugs designed to home in on this site, perhaps avoiding the drug resistance that some viruses have acquired to Tamiflu.

Bacterial meningitis remains a major cause of morbidity and mortality in young infants. Understanding the epidemiology and burden of disease is important. Prospective, enhanced, national population-based active surveillance was undertaken to determine the incidence, etiology, and outcome of bacterial meningitis in infants aged <90 days in the United Kingdom and Ireland. During July 2010-July 2011, 364 cases were identified (annual incidence, 0.38/1000 live births; 95% confidence interval [CI], .35-.42). In England and Wales, the incidence of confirmed neonatal bacterial meningitis was 0.21 (n = 167; 95% CI, .18-.25). A total of 302 bacteria were isolated in 298 (82%) of the cases. The pathogens responsible varied by route of admission, gestation at birth, and age at infection. Group B Streptococcus (GBS) (150/302 [50%]; incidence, 0.16/1000 live births; 95% CI, .13-.18) and Escherichia coli (41/302 [14%]; incidence, 0.04/1000; 95% CI, .03-.06) were responsible for approximately two-thirds of identified bacteria. Pneumococcal (28/302 [9%]) and meningococcal (23/302 [8%]) meningitis were rare in the first month, whereas Listeria meningitis was seen only in the first month of life (11/302 [4%]). In hospitalized preterm infants, the etiology of both early- and late-onset meningitis was more varied. Overall case fatality was 8% (25/329) and was higher for pneumococcal meningitis (5/26 [19%]) than GBS meningitis (7/135 [5%]; P = .04) and for preterm (15/90 [17%]) compared with term (10/235 [4%]; P = .0002) infants. The incidence of bacterial meningitis in young infants remains unchanged since the 1980s and is associated with significant case fatality. Prevention strategies and guidelines to improve the early management of cases should be prioritized.

Introduction:Emerging infectious diseases are increasingly recognized as a global threat to wildlife. Pandemics in amphibians, caused by the fungal pathogen Batrachochytrium dendrobatidis (Bd), have resulted in biodiversity loss at a global scale. Genomic data suggest a complex evolutionary history of Bd lineages that vary in pathogenicity. Africa harbors a significant proportion of global amphibian biodiversity, and multiple Bd lineages are known to occur there; yet, despite the decline of many host species, there are currently no described Bd-epizootics. Here, we describe the historical and recent biogeographical spread of Bd and assess its risk to amphibians across the continent of Africa.Methods:We provide a 165-year view of host-pathogen interactions by (i) employing a Bd assay to test 4,623 specimens (collected 1908–2013); (ii) compiling 12,297 published Bd records (collected 1852–2017); (iii) comparing the frequency of Bd-infected amphibians through time by both country and region; (iv) genotyping Bd lineages; (v) histologically identifying evidence of chytridiomycosis, and (vi) using a habitat suitability model to assess future Bd risk.Results:We found a pattern of Bd emergence beginning largely at the turn of the century. From 1852–1999, we found low Bd prevalence (3.2% overall) and limited geographic spread, but after 2000 we documented a sharp increase in prevalence (18.7% overall), wider geographic spread, and multiple Bd lineages that may be responsible for emergence in different regions. We found that Bd risk to amphibians was highest in much of eastern, central, and western Africa.Discussion:Our study documents a largely overlooked yet significant increase in a fungal pathogen that could pose a threat to amphibians across an entire continent. We emphasize the need to bridge historical and contemporary datasets to better describe and predict host-pathogen dynamics over larger temporal scales.

Background and Aims: Plant acquisition of endogenous forms of soil phosphorus (P) could reduce external P requirements in agricultural systems. This study investigated the interaction of citrate and phytase exudation in controlling the accumulation of P and depletion of soil organic P by transgenic Nicotiana tabacum plants. Methods: N. tabacum plant lines including wild-type, vector controls, transgenic plants with single-trait expression of a citrate transporter (A. thaliana frd3) or fungal phytases (phyA: A. niger, P. lycii) and crossed plant lines expressing both traits, were characterized for citrate efflux and phytase exudation. Monocultures and intercropped combinations of single-trait plants were grown in a low available P soil (12 weeks). Plant biomass, shoot P accumulation, rhizosphere soil pH and citrate-extractable-P fractions were determined. Land Equivalent Ratio and complementarity effect was determined in intercropped treatments and multiple-linearregression was used to predict shoot P accumulation based on plant exudation and soil P depletion. Results: Crossed plant lines with co-expression of citrate and phytase accumulated more shoot P than single-trait and intercropped plant treatments. Shoot P accumulation was predicted based on phytase-labile soil P, citrate efflux, and phytase activity (Rsq=0.58, P < .0001). Positive complementarity occurred between intercropped citrate-and phytase-exuding plants, with the greatest gains in shoot P occurring in plant treatments with A. niger phyA expression. Conclusions: We show for the first time that trait synergism associated with the exudation of citrate and phytase by tobacco can be linked to the improved acquisition of P and the depletion of soil organic P.

Abstract Airway mucus hypersecretion is a prominent feature of many obstructive lung diseases. We thus determined the ontogeny and exocytic phenotype of mouse airway mucous cells. In naive mice, ciliated (∼ 40%) and nonciliated (∼ 60%) epithelial cells line the airways, and > 95% of the nonciliated cells are Clara cells that contain Clara cell secretory protein (CCSP). Mucous cells comprise < 5% of the nonciliated cells. After sensitization and a single aerosol antigen challenge, alcian blue–periodic acid Schiff's positive mucous cell numbers increase dramatically, appearing 6 h after challenge (21% of nonciliated/nonbasal cells), peaking from Days 1–7 (99%), and persisting at Day 28 (65%). Throughout the induction and resolution of mucous metaplasia, ciliated and Clara cell numbers identified immunohistochemically change only slightly. Intracellular mucin content peaks at Day 7, and mucin expression is limited specifically to a Clara cell subset in airway generations 2–4 that continue to express CCSP. Functionally, Clara cells are secretory cells that express the regulated exocytic marker Rab3D and, in antigen-challenged mice, rapidly secrete mucin in response to inhaled ATP in a dose-dependent manner. Thus, Clara cells show great plasticity in structure and secretory products, yet have molecular and functional continuity in their identity as specialized apical secretory cells.