Urban landscapes and legacy industry provide hotspots for riverine greenhouse gases: A source-to-sea study of the River Clyde.

There is growing global concern that greenhouse gas (GHG) emissions from water bodies are increasing because of interactions between nutrient levels and climate warming. This paper investigates key land-cover, seasonal and hydrological controls of GHGs by comparison of the semi-natural, agricultural and urban environments in a detailed source-to-sea study of the River Clyde, Scotland. Riverine GHG concentrations were consistently oversaturated with respect to the atmosphere. High riverine concentrations of methane (CH4) were primarily associated with point source inflows from urban wastewater treatment, abandoned coal mines and lakes, with CH4-C concentrations between 0.1 - 44 µg l-1. Concentrations of carbon dioxide (CO2) and nitrous oxide (N2O) were mainly driven by nitrogen concentrations, dominated by diffuse agricultural inputs in the upper catchment and supplemented by point source inputs from urban wastewater in the lower urban catchment, with CO2-C concentrations between 0.1 - 2.6 mg l-1 and N2O-N concentrations between 0.3 - 3.4 µg l-1. A significant and disproportionate increase in all GHGs occurred in the lower urban riverine environment in the summer, compared to the semi-natural environment, where GHG concentrations were higher in winter. This increase and change in GHG seasonal patterns points to anthropogenic impacts on microbial communities. The loss of total dissolved carbon, to the estuary is approximately 48.4 ± 3.6 Gg C yr-1, with the annual inorganic carbon export approximately double that of organic carbon and four times that of CO2, with CH4 accounting for 0.03%, with the anthropogenic impact of disused coal mines accelerating DIC loss. The annual loss of total dissolved nitrogen to the estuary is approximately 4.03 ± 0.38 Gg N yr-1 of which N2O represents 0.06%. This study improves our understanding of riverine GHG generation and dynamics which can contribute to our knowledge of their release to the atmosphere. It identifies where action could support reductions in aquatic GHG generation and emission.

Nocturnal pollination: an overlooked ecosystem service vulnerable to environmental change.

Existing assessments of the ecosystem service of pollination have been largely restricted to diurnal insects, with a particular focus on generalist foragers such as wild and honey bees. As knowledge of how these plant-pollinator systems function, their relevance to food security and biodiversity, and the fragility of these mutually beneficial interactions increases, attention is diverting to other, less well-studied pollinator groups. One such group are those that forage at night. In this review, we document evidence that nocturnal species are providers of pollination services (including pollination of economically valuable and culturally important crops, as well as wild plants of conservation concern), but highlight how little is known about the scale of such services. We discuss the primary mechanisms involved in night-time communication between plants and insect pollen-vectors, including floral scent, visual cues (and associated specialized visual systems), and thermogenic sensitivity (associated with thermogenic flowers). We highlight that these mechanisms are vulnerable to direct and indirect disruption by a range of anthropogenic drivers of environmental change, including air and soil pollution, artificial light at night, and climate change. Lastly, we highlight a number of directions for future research that will be important if nocturnal pollination services are to be fully understood and ultimately conserved.

Mechanisms in mutualisms: a chemically mediated thrips pollination strategy in common elder.

MAIN CONCLUSION: This study provides first evidence of a thrips species pollinating Sambucus nigra and describes how interactions are driven by plant biochemical signalling and moderated by temporal changes in floral chemistry. The concept of flower-feeding thrips as pollinating insects in temperate regions is rarely considered as they are more frequently regarded to be destructive florivores feeding on pollen and surrounding plant tissue. Combining laboratory and field-based studies we examined interactions between Sambucus nigra (elderflower) and Thrips major within their native range to ascertain the role of thrips in the pollination of this species and to determine if floral chemicals mediated flower visits. If thrips provide a pollination service to S. nigra, then this will likely manifest in traits that attract the pollinating taxa at temporally critical points in floral development. T. major were highly abundant in inflorescences of S. nigra, entering flowers when stigmas were pollen-receptive and anthers were immature. When thrips were excluded from the inflorescences, fruit-set failed. Linalool was the major component of the inflorescence headspace with peak abundance coinciding with the highest number of adult thrips visiting flowers. Thrips were absent in buds and their numbers declined again in senescing flowers inversely correlating with the concentration of cyanogenic glycosides recorded in the floral tissue. Our data show that S. nigra floral chemistry mediates the behaviour of pollen-feeding thrips by attracting adults in high numbers to the flowers at pre-anthesis stage, while producing deterrent compounds prior to fruit development. Taking an integrative approach to studying thrips behaviour and floral biology we provide a new insight into the previously ambiguously defined pollination strategies of S. nigra and provide evidence suggesting that the relationship between T. major and S. nigra is mutualistic.

Survival Analysis of Occipital Nerve Stimulator Leads Placed under Fluoroscopic Guidance with and without Ultrasonography.

BACKGROUND: Electrical stimulation of the greater occipital nerves is performed to treat pain secondary to chronic daily headaches and occipital neuralgia. The use of fluoroscopy alone to guide the surgical placement of electrodes near the greater occipital nerves disregards the impact of tissue planes on lead stability and stimulation efficacy. OBJECTIVE: We hypothesized that occipital neurostimulator (ONS) leads placed with ultrasonography combined with fluoroscopy would demonstrate increased survival rates and times when compared to ONS leads placed with fluoroscopy alone. STUDY DESIGN: A 2-arm retrospective chart review. SETTING: A single academic medical center. METHODS: This retrospective chart review analyzed the procedure notes and demographic data of patients who underwent the permanent implant of an ONS lead between July 2012 and August 2015. Patient data included the diagnosis (reason for implant), smoking tobacco use, disability, and age. ONS lead data included the date of permanent implant, the imaging modality used during permanent implant (fluoroscopy with or without ultrasonography), and, if applicable, the date and reason for lead removal. A total of 21 patients (53 leads) were included for the review. Chi-squared tests, Fishers exact tests, 2-sample t-tests, and Wilcoxon rank-sum tests were used to compare fluoroscopy against combined fluoroscopy and ultrasonography as implant methods with respect to patient demographics. These tests were also used to evaluate the primary aim of this study, which was to compare the survival rates and times of ONS leads placed with combined ultrasonography and fluoroscopy versus those placed with fluoroscopy alone. Survival analysis was used to assess the effect of implant method, adjusted for patient demographics (age, smoking tobacco use, and disability), on the risk of lead explant. RESULTS: Data from 21 patients were collected, including a total of 53 ONS leads. There was no statistically significant difference in the lead survival rate or time, disability, or patient age with respect to the implant method with or without ultrasonography. There was a statistically significant negative effect on the risk of explant with regards to lead removal in smoking patients compared to non-smoking patients (hazard ratio 0.36). There was also a statistically significant difference in smoking tobacco use with respect to the implant method, such that a greater number of patients whose leads were placed with combined fluoroscopy and ultrasonography had a history of smoking (P = 0.048). LIMITATIONS: This study is a retrospective chart review that had statistically significant differences in the patient groups and a small sample size. CONCLUSION: This study assessed the survival rates and times of ONS leads placed with ultrasonography and fluoroscopy versus fluoroscopy alone. We did not observe an effect to suggest that the incremental addition of ultrasound guidance to fluoroscopy as the intraoperative imaging modality used during the permanent implant of ONS leads yields statistically significant differences in lead survival rate or time. Medical comorbidities, including age and smoking status, may play a role in determining the risk of surgical revision and should be considered in future studies. KEY WORDS: Neuromodulation, peripheral nerve stimulation, occipital nerve stimulation, occipital neuralgia, chronic daily headaches, ultrasonography.

Emergencies during home births.

This article reflects on how community midwifery skills days have assisted community midwives to develop confidence in managing unexpected emergencies at home births, and how team work, communication and working in partnership have supported women in their choices for birth.

Leaf chemistry and foliage avoidance by the thrips Frankliniella occidentalis and Heliothrips haemorrhoidalis in glasshouse collections.

Observational studies on foliage avoidance by the polyphagous thrips species Frankliniella occidentalis (Pergande) and Heliothrips haemorrhoidalis (Bouché) (Thysanoptera: Thripidae) identified six non-host species (Allagopappus dichotomus (Asteraceae), Gardenia posoquerioides (Rubiaceae), Plectranthus aff. barbatus, Plectranthus strigosus, Plectranthus zuluensis (Lamiaceae), and Sclerochiton harveyanus (Acanthaceae) among plants growing within a major glasshouse botanical collection. The effects of sequentially obtained acetone and aqueous methanol leaf extracts on mortality in first instar Frankliniella occidentalis were assessed. The acetone leaf extract of Sclerochiton harveyanus, which had the highest activity against the thrips, yielded four new iridoids, sclerochitonosides A-C, and sclerochitonoside B 4'-methyl ether. Mortality of F. occidentalis was increased on exposure to all four iridoids, and the most active iridoid was sclerochitonoside A (8-epiloganic acid 4'-hydroxyphenylethyl ester). Choice experiments demonstrated that this compound did not significantly deter H. haemorrhoidalis from treated leaf surfaces. The significance of iridoids in the defense mechanism of plants against thrips is discussed.

Relationship between nutritional composition of plant species and infestation levels of thrips.

Levels of soluble protein and carbohydrate (raffinose, sucrose, glucose, and fructose) in leaves from a selection of plant species were measured to determine if a relationship existed between these nutrients and infestation by Frankliniella occidentalis and Heliothrips haemorrhoidalis. Most species of host plant examined contained a higher proportion of protein than carbohydrates, and overall, leaves from species of plants that supported populations of thrips had greater levels of protein than leaves from nonhost species. New leaves and flowers that supported F. occidentalis contained high levels of carbohydrate and protein. The quantity of protein in leaves at the top of the tree, Peumus boldus, was greater than in leaves from lower levels, and the amount of feeding damage accrued by H. haemorrhoidalis was greater on the upper foliage than lower foliage. Oviposition by H. haenmorrhoidalis was positively correlated to levels of protein in host plants but not to levels of carbohydrates. Overall, levels of soluble protein in plants influenced their susceptibility to thrips more than levels of carbohydrates.