3,034 research outputs found
A commercial arbuscular mycorrhizal inoculum increases root colonization across wheat cultivars but does not increase assimilation of mycorrhizaâacquired nutrients
Production and heavy application of chemicalâbased fertilizers to maintain crop yields is unsustainable due to pollution from runâoff, high CO2 emissions, and diminishing yield returns. Access to fertilizers will be limited in the future due to rising energy costs and dwindling rock phosphate resources. A growing number of companies produce and sell arbuscular mycorrhizal fungal (AMF) inoculants, intended to help reduce fertilizer usage by facilitating crop nutrient uptake through arbuscular mycorrhizas. However, their success has been variable. Here, we present information about the efficacy of a commercially available AMF inoculant in increasing AMF root colonization and fungal contribution to plant nutrient uptake, which are critical considerations within the growing AMF inoculant industry.
Summary
Arable agriculture needs sustainable solutions to reduce reliance on large inputs of nutrient fertilizers while continuing to improve crop yields. By harnessing arbuscular mycorrhizal symbiosis, there is potential to improve crop nutrient assimilation and growth without additional inputs, although the efficacy of commercially available mycorrhizal inocula in agricultural systems remains controversial.
Using stable and radioisotope tracing, carbonâforânutrient exchange between arbuscular mycorrhizal fungi and three modern cultivars of wheat was quantified in a nonâsterile, agricultural soil, with or without the addition of a commercial mycorrhizal inoculant.
While there was no effect of inoculum addition on aboveâground plant biomass, there was increased root colonization by arbuscular mycorrhizal fungi and changes in community structure. Inoculation increased phosphorus uptake across all wheat cultivars by up to 30%, although this increase was not directly attributable to mycorrhizal fungi. Carbonâforânutrient exchange between symbionts varied substantially between the wheat cultivars.
Plant tissue phosphorus increased in inoculated plants potentially because of changes induced by inoculation in microbial community composition and/or nutrient cycling within the rhizosphere. Our data contribute to the growing consensus that mycorrhizal inoculants could play a role in sustainable food production systems of the future
Incidence and prevalence of inflammatory bowel disease in UK primary care: a population-based cohort study
OBJECTIVES: We describe temporal trends in the recorded incidence of inflammatory bowel disease (IBD) in UK primary care patients between 2000 and 2018. DESIGN: A cohort study. SETTING: The IQVIA Medical Research data (IMRD) primary care database. PARTICIPANTS: All individuals registered with general practices contributing to IMRD during the period 01 January 2000-31 December 2018. MAIN OUTCOME MEASURES: The primary outcome was the recorded diagnosis of IBD. RESULTS: 11 325 025 individuals were included and 65 700 IBD cases were identified, of which 22 560 were incident diagnoses made during the study period. Overall, there were 8077 incident cases of Crohn's disease (CD) and 12 369 incident cases of ulcerative colitis (UC). Crude incidence estimates of 'IBD overall', CD and UC were 28.6 (28.2 to 28.9), 10.2 (10.0 to 10.5) and 15.7 (15.4 to 15.9)/100 000 person years, respectively. No change in IBD incidence was observed for adults aged 17-40 years and children aged 0-9 years. However, for adults aged over 40 years, incidence fell from 37.8 (34.5 to 41.4) to 23.6 (21.3 to 26.0)/100 000 person years (average decrease 2.3% (1.9 to 2.7)/year (p<0.0001)). In adolescents aged 10-16 years, incidence rose from 13.1 (8.4 to 19.5) to 25.4 (19.5 to 32.4)/100 000 person years (average increase 3.0% (1.7 to 4.3)/year (p<0.0001)). Point prevalence estimates on 31 December 2018 for IBD overall, CD and UC were 725, 276 and 397 per 100 000 people, respectively. CONCLUSIONS: This is one of the largest studies ever undertaken to investigate trends in IBD epidemiology. Although we observed stable or falling incidence of IBD in adults, our results are consistent with some of the highest reported global incidence and prevalence rates for IBD, with a 94% rise in incidence in adolescents. Further investigation is required to understand the aetiological drivers
Inflammatory Bowel Disease in Uk Primary Care: Temporal Trends in Epidemiology During the Early 21st Century
Use of whole-genome sequencing to identify clusters of Shigella flexneri associated with sexual transmission in men who have sex with men in England: a validation study using linked behavioural data
Since the 1970s, shigellosis has been reported as a sexually transmissible infection, and in recent years, genomic data have revealed the breadth of Shigella spp. transmission among global networks of men who have sex with men (MSM). In 2015, Public Health England (PHE) introduced routine whole-genome sequencing (WGS) of Shigella spp. to identify transmission clusters. However, limited behavioural information for the cases hampers interpretation. We investigated whether WGS can distinguish between clusters representing sexual transmission in MSM and clusters representing community (non-sexual) transmission to inform infection control. WGS data for Shigella flexneri from August 2015 to July 2017 were aggregated into single linkage clusters based on SNP typing using a range of SNP distances (the standard for Shigella surveillance at PHE is 10 SNPs). Clusters were classified as 'adult male', 'household', 'travel-associated' or 'community' using routine demographic data submitted alongside laboratory cultures. From August 2015 to March 2017, PHE contacted those with shigellosis as part of routine public-health follow-up and collected exposure data on a structured questionnaire, which for the first time included questions about sexual identity and behaviour. The questionnaire data were used to determine whether clusters classified as 'adult male' represented likely sexual transmission between men, thereby validating the use of the SNP clustering tool for informing appropriate public-health responses. Overall, 1006âS. flexneri cases were reported, of which 563 clustered with at least one other case (10-SNP threshold). Linked questionnaire data were available for 106 clustered cases, of which 84.0â% belonged to an 'adult male' cluster. At the 10-SNP threshold, 95.1â% [95â% confidence interval (CI) 88.0-98.1%] of MSM belonged to an 'adult male' cluster, while 73.2â% (95â% CI 49.1-87.5%) of non-MSM belonged to a 'community' or 'travel-associated' cluster. At the 25-SNP threshold, all MSM (95â%âCI 96.0-100%) belonged to an 'adult male' cluster and 77.8â% (95â% CI 59.2-89.4%) of non-MSM belonged to a 'community' or 'travel-associated' cluster. Within one phylogenetic clade of S. flexneri, 9 clusters were identified (7 'adult male'; 2 'community') using a 10-SNP threshold, while a single 'adult male' cluster was identified using a 25-SNP threshold. Genotypic markers of azithromycin resistance were detected in 84.5â% (294/348) of 'adult male' cases and 20.9â% (9/43) of cases in other clusters (10-SNP threshold), the latter of which contained gay-identifying men who reported recent same-sex sexual contact. Our study suggests that SNP clustering can be used to identify Shigella clusters representing likely sexual transmission in MSM to inform infection control. Defining clusters requires a flexible approach in terms of genetic relatedness to ensure a clear understanding of underlying transmission networks
Household structure and its association with sexual risk behaviours and sexual health outcomes: Evidence from a British probability sample survey
Objectives: Economic and social changes over the last twenty years have led to changes in the living situations of young people in Britain. A personâs home-life context might influence their sexual behaviour, with implications for their sexual healthcare needs; we investigated this hypothesis. Methods: Britainâs third National Survey of Sexual Attitudes and Lifestyles (Natsal-3), a probability sample survey undertaken in 2010-2012, interviewed 15,162 men and women aged 16-74 years in Britain (with 3,869 aged 16-24 years). We examined household structure by gender and age-group. We then focused on sexually-experienced young people (aged 16-24 years), and used multivariable models to explore associations between household structure, sexual risk behaviours and sexual health outcomes, independent of confounders including age, relationship status, employment, and area of residence. Results: Young people were most likely to be living with parents (women 57.1% (95%CI 54.5%-59.6%) and men 68.7% (65.4%-71.8)), or non-relatives (women 10.5% (8.5%-12.9%) and men 12.6% (10.1%-15.6%)). Among the 81.3% of young people who were sexually-experienced, compared with young women living with parents (reference category), those living alone or with non-relatives had a higher likelihood of reporting â„2 sexual partners (adjusted odds ratio 1.54 (95%CI 1.03-2.31); 1.76 (1.03-3.00), respectively). Women living alone were also more likely to have had unsafe sex (2.04 (1.38-3.02)). Despite these differences in sexually transmitted infection risk, there was no difference in sexual healthcare-seeking behaviour. Young men and women living with partners reported lower levels of sexual risk behaviours. Conclusions: Our study suggests household structure may influence the sexual behaviour of young people in Britain. Given changes in their living arrangements, the role of household structure in sexual health research should be further investigated, and also considered as a possible marker for STI risk in clinical consultations
International health policy survey in 11 countries: assessment of non-response bias in the Norwegian sample
Characterizing eve: Analysing cybercrime actors in a large underground forum
Underground forums contain many thousands of active users, but the vast majority will be involved, at most, in minor levels of deviance. The number who engage in serious criminal activity is small. That being said, underground forums have played a significant role in several recent high-profile cybercrime activities. In this work we apply data science approaches to understand criminal pathways and characterize key actors related to illegal activity in one of the largest and longest- running underground forums. We combine the results of a logistic regression model with k-means clustering and social network analysis, verifying the findings using topic analysis. We identify variables relating to forum activity that predict the likelihood a user will become an actor of interest to law enforcement, and would therefore benefit the most from intervention. This work provides the first step towards identifying ways to deter the involvement of young people away from a career in cybercrime.Alan Turing Institut
Longer fixation duration while viewing face images
The spatio-temporal properties of saccadic eye movements can be influenced by the cognitive demand and the characteristics of the observed scene. Probably due to its crucial role in social communication, it is argued that face perception may involve different cognitive processes compared with non-face object or scene perception. In this study, we investigated whether and how face and natural scene images can influence the patterns of visuomotor activity. We recorded monkeysâ saccadic eye movements as they freely viewed monkey face and natural scene images. The face and natural scene images attracted similar number of fixations, but viewing of faces was accompanied by longer fixations compared with natural scenes. These longer fixations were dependent on the context of facial features. The duration of fixations directed at facial contours decreased when the face images were scrambled, and increased at the later stage of normal face viewing. The results suggest that face and natural scene images can generate different patterns of visuomotor activity. The extra fixation duration on faces may be correlated with the detailed analysis of facial features
Intensified shigellosis epidemic associated with sexual transmission in men who have sex with men - Shigella fexneri and s. Sonnei in England, 2004 to end of February 2015
Surveillance data suggest an intensification of the shigellosis epidemic associated with sexual transmission in men who have sex with men (MSM) in England with separate introductions into the population. In 2014, sexual transmission between MSM might have accounted for 97%, 89%, and 43% of non-travel associated Shigella flexneri 3a and S. flexneri 2a, and S. sonnei diagnoses. Clinicians should sensitively ascertain sexual history for men with enteric infections to facilitate prompt diagnosis and appropriate management
- âŠ