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Rhodococcus is a genus of Gram-positive bacteria with species that can cause growth deformations to a large number of plant species. This ability to cause disease is hypothesized to be dependent on a cluster of three gene loci on an almost 200 kb-sized linear plasmid. To reevaluate the roles of some of the genes in pathogenicity, we constructed and characterized deletion mutants of fasR and four fas genes. Findings confirmed that fasR, which encodes a putative transcriptional regulator, is necessary for pathogenesis. However, three of the fas genes, implicated in the metabolism of plant growth promoting cytokinins, are dispensable for the ability of the pathogen to cause disease. We also used long-read sequencing technology to generate high quality genome sequences for two phytopathogenic strains in which virulence genes are diverged in sequence and/or hypothesized to have recombined into the chromosome. Surprisingly, findings showed that the two strains carry extremely diverse virulence plasmids. Ortholog clustering identified only 12 genes present on all three virulence plasmids. Rhodococcus requires a small number of horizontally acquired traits to be pathogenic and the transmission of the corresponding genes, via recombination and conjugation, has the potential to rapidly diversify plasmids and bacterial populations.

Digital coherent receivers employing Alamouti-coding are a promising solution for passive optical networks (PON) with downstream rates of 100 Gb/s/λ. To reduce the cost by utilizing high-volume photodiodes designed for 25 Gb/s data-center applications, we consider 28-Gbaud 16-QAM modulation format detected with a single-polarization coherent receiver based on a 3 × 3 coupler with single-ended detection. We investigate two alternative configurations: first, a receiver with a symmetric 3 × 3 coupler and second, an IQ coupler (asymmetric 3 × 3 coupler) with Alamouti-coding based polarization diversity. In this paper, we present a detailed investigation as to the feasibility of both the receivers for a wide range of parameters including quantization noise, relative intensity noise, I/Q mismatch, etc. It is found that such receivers can be realized with commercially available components. We also quantify the penalty associated with nonideal components to allow for lower cost designs with reduced specifications suitable for access applications. In addition, we present the adaptive DSP algorithms required to recover data for a single-carrier Alamouti-coded signal. Considering both linear and nonlinear impairments, a power budget of 36.4 dB and 33.1 dB is found at BER of 3.8 × 10-3 for a receiver with symmetric 3 × 3 coupler and IQ coupler, respectively, and thereby proving their applicability as receivers for 100 Gb/s/λ PON.

The signalling scheme used in access networks require electrical bandwidths many times greater than subscribers can utilise. Here, the authors describe a promising approach to achieve bidirectional transmission with bandwidth-efficient yet low-complexity coherent optical network unit transceiver.

The transmission of infectious microbes via bioaerosols is of significant concern for both human and animal health. However, gaps in our understanding of respiratory pathogen transmission and methodological heterogeneity persist. New developments have enabled progress in this domain, and one of the major turning points has been the recognition that cross-disciplinary collaborations across spheres of human and animal health, microbiology, biophysics, engineering, aerobiology, infection control, public health, occupational health, and industrial hygiene are essential. Collaborative initiatives support advances in topics such as bioaerosol behavior, dispersion models, risk assessment, risk/exposure effects, and mitigation strategies in clinical, experimental, agricultural, and other field settings. There is a need to enhance the knowledge translation for researchers, stakeholders, and private partners to support a growing network of individuals and agencies to achieve common goals to mitigate inter- and intra-species pathogen transmission via bioaerosols.

Household electricity access data in Africa are scarce, particularly at the subnational level. We followed a model-based Geostatistics approach to produce maps of electricity access between 2000 and 2013 at a 5 km resolution. We collated data from 69 nationally representative household surveys conducted in Africa and incorporated nighttime lights imagery as well as land use and land cover data to produce maps of electricity access between 2000 and 2013. The information produced here can be an aid for understanding of how electricity access has changed in the region during this 14 year period. The resolution and the continental scale makes it possible to combine these data with other sources in applications in the socio-economic field, both at a local or regional level.

ObjectivesMaternal lifestyles, including diet, have been linked to infant birthweight. However, customised birthweight centiles (CBWC), which more accurately identify small babies that have increased fetal growth restriction and are at higher risk of newborn morbidity and later life health complications, are rarely considered when studying maternal diet. This study investigated maternal dietary patterns and their impact on infant CBWC within a cohort of women living in South Wales.MethodsThis study utilised cross-sectional data from the longitudinal Grown in Wales (GiW) cohort. Women 18-45 years old were recruited the morning prior to an elective caesarean section (ELCS). Women completed a food frequency questionnaire (FFQ). Additional data on pregnancy and birth outcomes was extracted from medical notes. Data from 303 participants was analysed.Results'Western' and 'Health conscious dietary patterns were identified. The 'Health Conscious' dietary pattern was significantly associated with maternal BMI, age, education, income and exercise. Adjusted regression analyses indicated that greater adherence to a 'Health Conscious' dietary pattern was significantly associated with increased CBWC (AOR = 4.75 [95% CI: 1.17, 8.33] p = .010) and reduced risk of delivering a small-for-gestational age (SGA) infant (AOR = .51 [95% CI: .26, .99] p = .046).ConclusionA healthier diet was significantly associated with higher birthweight using CBWC and a reduced risk of delivering an SGA infant suggesting that birthweight will be improved in areas of Wales by focused support encouraging healthier dietary habits.

The purpose of this study was to independently determine the levels of moderate-to-vigorous physical activity (MVPA) and self-determined motivation of both boys and girls as they participated in prolonged units of invasion games (i.e. 6-12 lessons) through two pedagogical models: direct instruction and the tactical games model (TGM). It was hypothesized that given the differences in domain interaction and lesson structure, both boys and girls would gain higher levels of physical activity (PA) and possess higher quality motivation during TGM-based lessons when compared to direct instruction lessons. Seventy-two children aged 11-12 years (42 boys, 30 girls) were randomly assigned to either a control or intervention group (TGM). Children wore RT3® triaxial accelerometers over a 12 week period to objectively measure time spent in MVPA. The System for Observing Fitness Instruction Time (SOFIT) tool was completed during each lesson to additionally assess lesson context information and teacher behaviour. SDT questionnaires were also completed, pre and post-intervention. Boys in the TGM condition displayed significantly higher levels of MVPA in both rugby and football activities in comparison to the control group although no significant differences in motivation were noted post-intervention. While girls in the TGM condition recorded comparable PA levels in the football sessions, they recorded significantly lower PA activity levels in the netball lessons. There were no significant differences in girls' motivation post-intervention. It is recommended that future studies build on this research by continuing to examine PA and the quality of student motivation while using GCAs over prolonged unit lengths (i.e. greater than 12 lessons) using structural equation modelling techniques to assess the relationships between, and mediating influences of, SDT constructs on PA levels.

We investigated the moderate to vigorous physical activity (MVPA) and vigorous physical activity (VPA) levels of pupils during coeducational physical education units focused on direct instruction and tactical games models (TGM). Thirty-two children (11-12 years, 17 girls) were randomly assigned to either a direct instruction (control) or TGM (intervention) group. Children wore RT3 triaxial accelerometers over 6 physical education lessons focused on field hockey to measure time spent in MVPA and VPA objectively.The System for Observing Fitness Instruction Time (SOFIT) was also used during each lesson to examine pupil physical activity, lesson context, and teacher behaviors. Results from accelerometry show MVPA and VPA were significantly higher in the TGM class compared to the class taught using direct instruction. SOFIT lesson context data show the TGM teacher spent less time managing and more time in skill practice and game play. The results of this study indicate that a shift in games pedagogy to TGM, in which the central aspect is participation in modified/conditioned games, is more likely to provide pupils the opportunity to achieve current physical activity guidelines stipulated by the Department of Health (2011) and the Institute of Medicine (2013).

Expression of oral stereotypies directed at the drinker (drinking) empty feeder (pecking), by young, caged, restricted-fed broiler breeder fowls, investigated in three experiments in which either the frequency of feeding or meal as varied. Behaviour was measured from regular 15-min videorecordings.  Experiment 1, birds were provided with either one (lA), two (IB) or four meals of 5 g in the morning, and a single balance meal in the afternoon. caused increases in drinking and pecking, compared with lA and IB, but effects meal number and the total weight of food eaten during testing were In Experiment 2, birds were provided with four meals of equal size in the morning,  either 1.5, 1 or 0.5 hr intervals, with a balance meal in the afternoon in the first only. There was no difference among these treatments in drinking or pecking at time, and neither stereotypy responded to variation in inter-feeding interval length the ways predicted by two alternative theoretical models, constructed for from Experiment 1, and a 1 and 2, indicated that both stereotypies were correlated meal size and/or the total amount eaten during testing. In Experiment 3, birds provided with two meals (only) of unequal size at 09.00 and 12.00 h, conditioned to receiving either the large meal (32 g) first, the small meal (8 g) first, and small meals in random order. The main finding was that pecking from the first to the third hour after the small meal only when the small meal first, and did not do so after the large meal. This suggests that the rate at stereotyped pecking declines after eating may depend on the amount that is eaten.

Intwo experiments, 24 immature female broiler breeder fowls housed in two 12-cage battery units in identical rooms received a single daily ration which they ate in 10 min, according to a programme of food restriction. From regular 15-min videorecordings, measurements were made of times spent in mutually exclusive activities (sitting, standing, head out, pacing, preening, object pecking, drinker activity). In Experiment 1, feeding time was 09.00 h in one room and 13.00 h in the other, and all birds were videorecorded in every hour of the (14-h) photoperiod on two lternate days. Differences in behaviour before and after feeding were independent of feeding time. In both rooms, head out and pacing increased before feeding, and object pecking and drinker activity (oral stereotypies) commenced immediately afterwards and then declined. Individual variation in the oral stereotypies was significant, and individuals' mean levels of both stereotypies together were consistent on the two days, but their hourly patterns were less so. Experiment 2 tested the notion of homeostatic control of oral stereotypies, by feeding all birds at 09.00 h and measuring their responses to removal of drinkers and empty feeders (main targets of the stereotypies) for either 0, 1.5 or 3 h before 15.00 h. Each cage tier received each treatment once, over three alternate days when all birds were recorded on video between 12.00 and 18.00 h (lights ofQ. During removal of feeders and drinkers, partial suppression of object pecking and total suppression of drinker activity were balanced by corresponding increases in sitting, head out and preening. After the return of feeders and drinkers, preening declined and both stereotypies showed evidence of post-inhibitory rebound, but there was no difference between 1.5 and 3 h removal treatments. The results concur with earlier evidence  indicating that preening can substitute with oral stereotypies, and it is suggested they may demonstrate homeostasis in total (substitutable) oral activity over the whole test. Conceivably, homeostasis of arousal may underlie changes in broiler breeder behaviour before and after feeding time.

Pore-forming toxins act by forming oligomeric pores in lipid membranes. Here the authors report the crystal structure of the lysenin pore, providing insights into the assembly and function of the pore in addition to suggesting that its properties make lysenin potentially well-suited for nanopore sensing applications.

The temperature-dependence of the band gap of the proposed photovoltaic absorber copper antimony sulphide (CuSbS2) has been studied by Fourier-transform infrared spectroscopy. The direct gap rises from 1.608 to 1.694 eV between 300 and 4.2 K. Below 200 K an exciton-like feature develops above the absorption edge at 1.82 eV. First-principles calculations evaluate band structure, band symmetries, and dipole selection rules, suggesting distinctly enhanced absorption for certain excitonic optical transitions. Striking consistency is seen between predicted dielectric and absorption spectra and those determined by ellipsometry, which reveal rapidly strengthening absorption passing 105 cm−1 at 2.2 eV. These results suggest beneficial photovoltaic performance due to strong optical absorption arising from unusually strong electron–hole interactions in polycrystalline CuSbS2 material.

BACKGROUND:Although randomized trials have established the clinical efficacy of treating all persons living with HIV (PLWHs), expanding treatment eligibility in the real world may have additional behavioral effects (e.g., changes in retention) or lead to unintended consequences (e.g., crowding out sicker patients owing to increased patient volume). Using a regression discontinuity design, we sought to assess the effects of a previous change to Zambia's HIV treatment guidelines increasing the threshold for treatment eligibility from 350 to 500 cells/μL to anticipate effects of current global efforts to treat all PLWHs. METHODS AND FINDINGS:We analyzed antiretroviral therapy (ART)-naïve adults who newly enrolled in HIV care in a network of 64 clinics operated by the Zambian Ministry of Health and supported by the Centre for Infectious Disease Research in Zambia (CIDRZ). Patients were restricted to those enrolling in a narrow window around the April 1, 2014 change to Zambian HIV treatment guidelines that raised the CD4 threshold for treatment from 350 to 500 cells/μL (i.e., August 1, 2013, to November 1, 2014). Clinical and sociodemographic data were obtained from an electronic medical record system used in routine care. We used a regression discontinuity design to estimate the effects of this change in treatment eligibility on ART initiation within 3 months of enrollment, retention in care at 6 months (defined as clinic attendance between 3 and 9 months after enrollment), and a composite of both ART initiation by 3 months and retention in care at 6 months in all new enrollees. We also performed an instrumental variable (IV) analysis to quantify the effect of actually initiating ART because of this guideline change on retention. Overall, 34,857 ART-naïve patients (39.1% male, median age 34 years [IQR 28-41], median CD4 268 cells/μL [IQR 134-430]) newly enrolled in HIV care during this period; 23,036 were analyzed after excluding patients around the threshold to allow for clinic-to-clinic variations in actual guideline uptake. In all newly enrolling patients, expanding the CD4 threshold for treatment from 350 to 500 cells/μL was associated with a 13.6% absolute increase in ART initiation within 3 months of enrollment (95% CI, 11.1%-16.2%), a 4.1% absolute increase in retention at 6 months (95% CI, 1.6%-6.7%), and a 10.8% absolute increase in the percentage of patients who initiated ART by 3 months and were retained at six months (95% CI, 8.1%-13.5%). These effects were greatest in patients who would have become newly eligible for ART with the change in guidelines: a 43.7% increase in ART initiation by 3 months (95% CI, 37.5%-49.9%), 13.6% increase in retention at six months (95% CI, 7.3%-20.0%), and a 35.5% increase in the percentage of patients on ART at 3 months and still in care at 6 months [95% CI, 29.2%-41.9%). We did not observe decreases in ART initiation or retention in patients not directly targeted by the guideline change. An IV analysis found that initiating ART in response to the guideline change led to a 37.9% (95% CI, 28.8%-46.9%) absolute increase in retention in care. Limitations of this study include uncertain generalizability under newer models of care, lack of laboratory data (e.g., viral load), inability to account for earlier stages in the HIV care cascade (e.g., HIV testing and linkage), and potential for misclassification of eligibility status or outcome. CONCLUSIONS:In this study, guidelines raising the CD4 threshold for treatment from 350 to 500 cells/μL were associated with a rapid rise in ART initiation as well as enhanced retention among newly treatment-eligible patients, without negatively impacting patients with lower CD4 levels. These data suggest that health systems in Zambia and other high-prevalence settings could substantially enhance engagement even among those with high CD4 levels (i.e., above 500 cells/μL) by expanding treatment without undermining existing care standards.

Randall et al., 2018 and Vereecke, 2018 have raised concerns about a paper we published (Savory et al., 2017). Here, we respond to those concerns.

Understanding how bacteria affect plant health is crucial for developing sustainable crop production systems. We coupled ecological sampling and genome sequencing to characterize the population genetic history of Rhodococcus and the distribution patterns of virulence plasmids in isolates from nurseries. Analysis of chromosome sequences shows that plants host multiple lineages of Rhodococcus, and suggested that these bacteria are transmitted due to independent introductions, reservoir populations, and point source outbreaks. We demonstrate that isolates lacking virulence genes promote beneficial plant growth, and that the acquisition of a virulence plasmid is sufficient to transition beneficial symbionts to phytopathogens. This evolutionary transition, along with the distribution patterns of plasmids, reveals the impact of horizontal gene transfer in rapidly generating new pathogenic lineages and provides an alternative explanation for pathogen transmission patterns. Results also uncovered a misdiagnosed epidemic that implicated beneficial Rhodococcus bacteria as pathogens of pistachio. The misdiagnosis perpetuated the unnecessary removal of trees and exacerbated economic losses.

Pseudoperonospora cubensis is an obligate pathogen and causative agent of cucurbit downy mildew. To help advance our understanding of the pathogenicity of P. cubensis, we used RNA-Seq to improve the quality of its reference genome sequence. We also characterized the RNA-Seq dataset to inventory transcript isoforms and infer alternative splicing during different stages of its development. Almost half of the original gene annotations were improved and nearly 4,000 previously unannotated genes were identified. We also demonstrated that approximately 24% of the expressed genome and nearly 55% of the intron-containing genes from P. cubensis had evidence for alternative splicing. Our analyses revealed that intron retention is the predominant alternative splicing type in P. cubensis, with alternative 5′- and alternative 3′-splice sites occurring at lower frequencies. Representatives of the newly identified genes and predicted alternatively spliced transcripts were experimentally validated. The results presented herein highlight the utility of RNA-Seq for improving draft genome annotations and, through this approach, we demonstrate that alternative splicing occurs more frequently than previously predicted. In total, the current study provides evidence that alternative splicing plays a key role in transcriptome regulation and proteome diversification in plant-pathogenic oomycetes.

Case summary A 16-year-old, castrated male, feline immunodeficiency virus (FIV)-positive, domestic shorthair cat developed multiple skin lesions. Most of these were Bowenoid carcinoma in situ and contained DNA sequences consistent with Felis catus papillomavirus type 2. Two additional lesions that developed in the skin and subcutaneous tissues between the digital and carpal pads on the left forelimb and right hindlimb were shown by cytology, histology and culture to be caused by Prototheca wickerhamii . These lesions failed to improve in response to systemic therapy treatment with itraconazole, but excision by sharp en bloc resection with follow-up oral itraconazole therapy proved curative for one lesion, although the other lesion recurred, necessitating a second surgery. Relevance and novel information This is only the second reported case of feline protothecosis from Australia and the first case that has been cultured and identified to the species level. Also of great interest was the presence of multiple papillomavirus-associated neoplastic lesions, which may have afforded a portal of entry for the algal pathogen and the cat’s positive FIV status; the latter might have impacted on both viral and algal pathogenesis by effects on immunocompetence.

Quantifying and monitoring the spatial and temporal dynamics of the global land cover is critical for better understanding many of the Earth's land surface processes. However, the lack of regularly updated, continental-scale, and high spatial resolution (30 m) land cover data limit our ability to better understand the spatial extent and the temporal dynamics of land surface changes. Despite the free availability of high spatial resolution Landsat satellite data, continental-scale land cover mapping using high resolution Landsat satellite data was not feasible until now due to the need for high-performance computing to store, process, and analyze this large volume of high resolution satellite data. In this study, we present an approach to quantify continental land cover and impervious surface changes over a long period of time (15 years) using high resolution Landsat satellite observations and Google Earth Engine cloud computing platform. The approach applied here to overcome the computational challenges of handling big earth observation data by using cloud computing can help scientists and practitioners who lack high-performance computational resources.

Pathogens belonging to the Oomycota, a group of heterokont, fungal-like organisms, are amongst the most notorious pathogens in agriculture. In particular, the obligate biotrophic downy mildews and the hemibiotrophic members of the genus Phytophthora are responsible for a huge variety of destructive diseases, including sudden oak death caused by P. ramorum, potato late blight caused by P. infestans, cucurbit downy mildew caused by Pseudoperonospora cubensis, and grape downy mildew caused by Plasmopara viticola. About 800 species of downy mildews and roughly 100 species of Phytophthora are currently accepted, and recent studies have revealed that these groups are closely related. However, the degree to which Phytophthora is paraphyletic and where exactly the downy mildews insert into this genus in relation to other clades could not be inferred with certainty to date. Here we present a molecular phylogeny encompassing all clades of Phytophthora as represented in a multi-locus dataset and two representatives of the monophyletic downy mildews from divergent genera. Our results demonstrate that Phytophthora is at least six times paraphyletic with respect to the downy mildews. The downy mildew representatives are consistently nested within clade 4 (contains Phytophthora palmivora), which is placed sister to clade 1 (contains Phytophthora infestans). This finding would either necessitate placing all downy mildews and Phytopthora species in a single genus, either under the oldest generic name Peronospora or by conservation the later name Phytophthora, or the description of at least six new genera within Phytophthora. The complications of both options are discussed, and it is concluded that the latter is preferable, as it warrants fewer name changes and is more practical.

Pseudoperonospora cubensis is a biotrophic oomycete pathogen that causes downy mildew of cucurbits, a devastating foliar disease threatening cucurbit production worldwide. We sequenced P. cubensis genomic DNA using 454 pyrosequencing and obtained random genomic sequences covering approximately 14% of the genome, thus providing the first set of useful genomic sequence information for P. cubensis. Using bioinformatics approaches, we identified 32 putative RXLR effector proteins. Interestingly, we also identified 29 secreted peptides with high similarity to RXLR effectors at the N-terminal translocation domain, yet containing an R-to-Q substitution in the first residue of the translocation motif. Among these, a family of QXLR-containing proteins, designated as PcQNE, was confirmed to have a functional signal peptide and was further characterized as being localized in the plant nucleus. Internalization of secreted PcQNE into plant cells requires the QXLR-EER motif. This family has a large number of near-identical copies within the P. cubensis genome, is under diversifying selection at the C-terminal domain, and is upregulated during infection of plants, all of which are common characteristics of characterized oomycete effectors. Taken together, the data suggest that PcQNE are bona fide effector proteins with a QXLR translocation motif, and QXLR effectors are prevalent in P. cubensis. Furthermore, the massive duplication of PcQNE suggests that they might play pivotal roles in pathogen fitness and pathogenicity.

It can be difficult estimating all of the cost components that are attributed to a machined part. This problem is more pronounced when a factory uses group technology manufacturing cells as opposed to a functional or process layout of a job shop. This paper describes how activity-based costing (ABC) concepts can be integrated into a discrete-event simulation model of a U-shaped manufacturing cell producing a part family with four members. The simulation model generates detailed Bills of Activity for each part type and includes specific information about the cost drivers and cost pools. The enhanced model output can be used for cost estimation and analysis, manufacturing cell design, part scheduling and other manufacturing decision processes that involve economic considerations. Although the scope of this effort is restricted to a small scale manufacturing cell, the costing concepts have general applicability to manufacturing operations at all levels.

Mentoring for trainee teachers in the learning and skills sector has taken on a greater significance due to the recent demands of providing subject-specialist support in what is otherwise a generic training programme. This article reports on one of the research projects undertaken on behalf of the Peninsular CETT that were commissioned in order to improve the understanding of and the practice of mentoring in the region. The research focussed on investigating what factors contributed to successful mentoring relationships for part-time trainees who were working in Further Education (FE) colleges. The findings, based on case-study analysis emphasise the importance of personal relationships in the mentoring process, alongside the benefits of frequent and informal meetings based on mutual respect. The findings also highlighted the need for a clear definition and understanding of roles and responsibilities and adequate training and time for mentors. While these points are not surprising they do pose challenges for a system that now demands more formality and has to cover a very wide range of trainees working in different circumstances.

Glial cell line-derived neurotrophic factor (GDNF) is a potent survival agent for neurons, however, its effect on Aβ-evoked neuronal death has not been examined. We show that the injection of Aβ into New Zealand white rabbit brain activates the endoplasmic reticulum (ER) chaperones, grp 78 and grp 94, and the transcription factor, gadd 153. These effects correlate with the activation of JNK and ERK as well as of microglia and with the phosphorylation of tau protein. Treatment with GDNF inhibits the activation of gadd 153, reduces the phosphorylation of JNK, abolishes the phosphorylation of ERK, prevents microglial activation, greatly reduces apoptotic cells, and does not affect the phosphorylation of tau. Our data suggest that the tau hyperphosphorylation and apoptosis triggered by Aβ are two independent events, and that the neuroprotective effect of GDNF against Aβ may result either directly by the inhibition of ER stress or indirectly through the inhibition of JNK and ERK activation.

Sub-Saharan Africa currently has the world’s highest urban population growth rate of any continent at roughly 4.2% annually. A better understanding of the spatiotemporal dynamics of urbanization across the continent is important to a range of fields including public health, economics, and environmental sciences. Nighttime lights imagery (NTL), maintained by the National Oceanic and Atmospheric Administration, offers a unique vantage point for studying trends in urbanization. A well-documented deficiency of this dataset is the lack of intra- and inter-annual calibration between satellites, which makes the imagery unsuitable for temporal analysis in their raw format. Here we have generated an ‘intercalibrated’ time series of annual NTL images for Africa (2000–2013) by building on the widely used invariant region and quadratic regression method (IRQR). Gaussian process methods (GP) were used to identify NTL latent functions independent from the temporal noise signals in the annual datasets. The corrected time series was used to explore the positive association of NTL with Gross Domestic Product (GDP) and urban population (UP). Additionally, the proportion of change in ‘lit area’ occurring in urban areas was measured by defining urban agglomerations as contiguously lit pixels of >250 km2, with all other pixels being rural. For validation, the IRQR and GP time series were compared as predictors of the invariant region dataset. Root mean square error values for the GP smoothed dataset were substantially lower. Correlation of NTL with GDP and UP using GP smoothing showed significant increases in R2 over the IRQR method on both continental and national scales. Urban growth results suggested that the majority of growth in lit pixels between 2000 and 2013 occurred in rural areas. With this study, we demonstrated the effectiveness of GP to improve conventional intercalibration, used NTL to describe temporal patterns of urbanization in Africa, and detected NTL responses to environmental and humanitarian crises. The smoothed datasets are freely available for further use.

Members of Gram-positive Actinobacteria cause economically important diseases to plants. Within the Rhodococcus genus, some members can cause growth deformities and persist as pathogens on a wide range of host plants. The current model predicts that phytopathogenic isolates require a cluster of three loci present on a linear plasmid, with the fas operon central to virulence. The Fas proteins synthesize, modify, and activate a mixture of growth regulating cytokinins, which cause a hormonal imbalance in plants, resulting in abnormal growth. We sequenced and compared the genomes of 20 isolates of Rhodococcus to gain insights into the mechanisms and evolution of virulence in these bacteria. Horizontal gene transfer was identified as critical but limited in the scale of virulence evolution, as few loci are conserved and exclusive to phytopathogenic isolates. Although the fas operon is present in most phytopathogenic isolates, it is absent from phytopathogenic isolate A21d2. Instead, this isolate has a horizontally acquired gene chimera that encodes a novel fusion protein with isopentyltransferase and phosphoribohydrolase domains, predicted to be capable of catalyzing and activating cytokinins, respectively. Cytokinin profiling of the archetypal D188 isolate revealed only one activate cytokinin type that was specifically synthesized in a fas-dependent manner. These results suggest that only the isopentenyladenine cytokinin type is synthesized and necessary for Rhodococcus phytopathogenicity, which is not consistent with the extant model stating that a mixture of cytokinins is necessary for Rhodococcus to cause leafy gall symptoms. In all, data indicate that only four horizontally acquired functions are sufficient to confer the trait of phytopathogenicity to members of the genetically diverse clade of Rhodococcus.

Direct (intracisternal) injection of aluminum complexes into rabbit brain results in a number of similarities with the neuropathological and biochemical changes observed in Alzheimer's disease and provides the opportunity to assess early events in neurodegeneration. This mode of administration induces cytochrome c release from mitochondria, a decrease in Bcl-2 in both mitochondria and endoplasmic reticulum, Bax translocation into mitochondria, activation of caspase-3, and DNA fragmentation. Coadministration of glial cell neuronal-derived factor (GDNF) inhibits these Bcl-2 and Bax changes, upregulates Bcl-XL, and abolishes the caspase-3 activity. Furthermore, treatment with GDNF dramatically inhibits apoptosis, as assessed by the TUNEL technique for detecting DNA damage. Treatment with GDNF may represent a therapeutic strategy to reverse the neuronal death associated with Alzheimer's disease and may exert its effect on apoptosis-regulatory proteins.