Minimizing the impacts of the ammonia economy on the nitrogen cycle and climate

Ammonia (NH3) is an attractive low-carbon fuel and hydrogen carrier. However, losses and inefficiencies across the value chain could result in reactive nitrogen emissions (NH3, NOx, and N2O), negatively impacting air quality, the environment, human health, and climate. A relatively robust ammonia economy (30 EJ/y) could perturb the global nitrogen cycle by up to 65 Mt/y with a 5% nitrogen loss rate, equivalent to 50% of the current global perturbation caused by fertilizers. Moreover, the emission rate of nitrous oxide (N2O), a potent greenhouse gas and ozone-depleting molecule, determines whether ammonia combustion has a greenhouse footprint comparable to renewable energy sources or higher than coal (100 to 1,400 gCO2e/kWh). The success of the ammonia economy hence hinges on adopting optimal practices and technologies that minimize reactive nitrogen emissions. We discuss how this constraint should be included in the ongoing broad engineering research to reduce environmental concerns and prevent the lock-in of high-leakage practices.

Human impacts on the world’s raptors

Raptors are emblematic of the global biodiversity crisis because one out of five species are threatened with extinction and over half have declining populations due to human threats. Yet our understanding of where these “threats” impact raptor species is limited across terrestrial Earth. This is concerning because raptors, as apex predators, are critically positioned in ecological food webs, and their declining populations can undermine important ecosystem services ranging from pest control to disease regulation. Here, we map the distribution of 15 threats within the known ranges of 172 threatened and near threatened raptor species globally as declared by the International Union for the Conservation of Nature. We analyze the proportion of each raptor range that is exposed to threats, identify global hotspots of impacted raptor richness, and investigate how human impacts on raptors vary based on several intrinsic (species traits) and extrinsic factors. We find that humans are potentially negatively affecting at least one threatened raptor species across three quarters of Earth’s terrestrial area (78%; 113 million km2). Our results also show that raptors have 66% of their range potentially impacted by threats on average (range 2.7–100%). Alarmingly, critically endangered species have 90% of their range impacted by threats on average. We also highlight 57 species (33%) of particular concern that have > 90% of their ranges potentially impacted. Without immediate conservation intervention, these 57 species, including the most heavily impacted Forest Owlet (Athene blewitti), the Madagascar Serpent-eagle (Eutriorchis astur), and the Rufous Fishing-owl (Scotopelia ussheri), will likely face extinction in the near future. Global “hotspots” of impacted raptor richness are ubiquitous, with core areas of threat in parts of the Sahel and East Africa where 92% of the assessed raptors are potentially impacted per grid cell (10 species on average), and in Northern India where nearly 100% of raptors are potentially impacted per grid cell (11 species). Additionally, “coolspots” of unimpacted richness that represent refuges from threats occur in Greenland and Canada, where 98 and 58% of raptors are potentially unimpacted per grid cell, respectively (nearly one species on average), Saharan Africa, where 21% of raptors are potentially unimpacted per grid cell (one species on average), and parts of the Amazon, where 12% of raptors are potentially unimpacted per grid cell (0.6 species on average). The results provide essential information to guide conservation planning and action for the world’s imperiled raptors.

Measuring corporate Paris Compliance using a strict science-based approach

The achievement of the Paris Agreement climate goals of well-below 2 degrees of warming requires companies to align their greenhouse gas emission reductions with this goal. To measure whether companies are compliant with the Paris targets we propose several strict conditions that any emissions allocation methodology must meet before it can be classified as Paris-Compliant. Our conditions focus on the need for a common, and early as practicable, base year for all companies and consistency with an underlying Paris-aligned decarbonisation pathway. Additionally, we propose four operationalisation requirements to ensure companies can declare they are on a Paris Compliant Pathway including calculations of their carbon budgets and re-alignment pathways. Applying example Paris-Compliant Pathways and associated metrics to ten high emission electric utility companies and ten cement companies, we find that all but one of these companies are not currently Paris-compliant, with every year of delayed action increasing their required rate of decarbonisation and hence the exposure of billions of investment dollars to transition risk. Applying this proposed method will ensure the Paris carbon budget is met and that progress can be tracked accurately - an imperative for any companies and stakeholders seeking to align their decision-making with the Paris Agreement.

Realizing ambitions: A framework for iteratively assessing and communicating national decarbonization progress

A growing number of governments are pledging to achieve net-zero greenhouse gas emissions by mid-century. Despite such ambitions, realized emissions reductions continue to fall alarmingly short of modeled energy transition pathways for achieving net-zero. This gap is largely a result of the difficulty of realistically modeling all the techno-economic and sociopolitical capabilities that are required to deliver actual emissions reductions. This limitation of models suggests the need for an energy-systems analytical framework that goes well beyond energy-system modeling in order to close the gap between ambition and reality. Toward that end, we propose the Emissions-Sustainability-Governance-Operation (ESGO) framework for structured assessment and transparent communication of national capabilities and realization. We illustrate the critical role of energy modeling in ESGO using recent net-zero modeling studies for the world's two largest emitters, China and the United States. This illustration leads to recommendations for improvements to energy-system modeling to enable more productive ESGO implementation.

Cross sectional imaging of truncal and quadriceps muscles relates to different functional outcomes in cancer

Introduction

Following the consensus definition of cancer cachexia, more studies are using CT scan analysis of truncal muscles as a marker of muscle wasting. However, how CT-derived body composition relates to function, strength and power in patients with cancer is largely unknown.

Aims

We aimed to describe the relationship between CT truncal (L3) skeletal muscle index (SMI) and MRI quadriceps cross sectional area with lower limb strength, power and measures of complex function.

Methods

Patients undergoing assessment for potentially curative surgery for oesophagogastric or pancreatic cancer were recruited from the regional upper gastrointestinal (UGI) or hepatopancreaticobiliary (HPB) multi-disciplinary team meetings. Maximum Isometric Knee Extensor Strength (IKES) and Maximum Leg Extensor Power (Nottingham Power Rig) (LEP) were used as measures of lower limb performance. Both Sit to Stand (STS) and Timed Up and Go (TUG) were used as measures of global complex muscle function. Muscle SMI was measured from routine CT scans at the level of the third lumbar vertebrae (L3) and MRI scan was used for the assessment of quadriceps muscles. Linear regression analysis was performed for CT SMI or MRI quadriceps as a predictor of each measure of performance.

Results

Forty-four patients underwent assessment. Height and weight were significantly related to function in terms of quadriceps power, while only weight was associated with strength (P < 0.001). CT SMI was not related to measures of quadriceps strength or power but had significant association with more complex functional measures (P = 0.006, R² = 0.234 and 0.0019, R² = 0.175 for STS and TUG respectively). In comparison, both gross and fat-subtracted measures of quadriceps muscle mass from MRI were significantly correlated with quadriceps strength and power (P < 0.001), but did not show any significant association with complex functional measures.

Conclusion

CT SMI and MRI quadriceps have been shown to reflect different aspects of functional ability with CT SMI being a marker of global muscle function and MRI quadriceps being specific to quadriceps power and strength. This should therefore be considered when choosing outcome measures for trials or definitions of muscle mass and function.

First Melody(®) valve implantations in Africa

Congenital heart lesions involving the right ventricular outflow tract (RVOT) are a common problem in paediatric cardiology. These patients need multiple surgical interventions in the form of valved conduits over a lifetime. Surgical re-valvulation was the standard treatment option until the introduction of percutaneous pulmonary valves over a decade ago. These valves can be used to prolong the lifespan of conduits and reduce the number of re-operations. The Melody(®) valve (Medtronic, Minneapolis, MN, USA) was introduced as the first dedicated percutaneous pulmonary valve. Percutaneous pulmonary valves can be implanted successfully and have the advantage of short hospitalisations. We describe the first three Melody(®) valve implantations in Africa.

More than a colour change: insect melanism, disease resistance and fecundity

A 'dark morph' melanic strain of the greater wax moth, Galleria mellonella, was studied for its atypical, heightened resistance to infection with the entomopathogenic fungus, Beauveria bassiana. We show that these insects exhibit multiple intraspecific immunity and physiological traits that distinguish them from a non-melanic, fungus-susceptible morph. The melanic and non-melanic morphs were geographical variants that had evolved different, independent defence strategies. Melanic morphs exhibit a thickened cuticle, higher basal expression of immunity- and stress-management-related genes, higher numbers of circulating haemocytes, upregulated cuticle phenoloxidase (PO) activity concomitant with conidial invasion, and an enhanced capacity to encapsulate fungal particles. These insects prioritize specific augmentations to those frontline defences that are most likely to encounter invading pathogens or to sustain damage. Other immune responses that target late-stage infection, such as haemolymph lysozyme and PO activities, do not contribute to fungal tolerance. The net effect is increased larval survival times, retarded cuticular fungal penetration and a lower propensity to develop haemolymph infections when challenged naturally (topically) and by injection. In the absence of fungal infection, however, the heavy defence investments made by melanic insects result in a lower biomass, decreased longevity and lower fecundity in comparison with their non-melanic counterparts. Although melanism is clearly correlated with increased fungal resistance, the costly mechanisms enabling this protective trait constitute more than just a colour change.

Expression of bacterial levanase in yeast enables simultaneous saccharification and fermentation of grass juice to bioethanol

This study demonstrates use of recombinant yeast to simultaneously saccharify and ferment grass juice (GJ) to bioethanol. A modified Bacillus subtilis levanase gene (sacC) in which the native bacterial signal sequence was replaced with a yeast α-factor domain, was synthesised with yeast codon preferences and transformed into Saccharomyces cerevisiae (strain AH22) using the expression vector pMA91. AH22:psacC transformants secreted sacCp as an active, hyper-glycosylated (>180 kDa) protein allowing them to utilise inulin (β[2-1] linked fructose) and levan (β[2-6] linkages) as growth substrates. The control (AH22:pMA91) strain, transformed with empty plasmid DNA was not able to utilise inulin or levan. When cultured on untreated GJ levels of growth and bioethanol production were significantly higher in experiments with AH22:psacC than with AH22:pMA91. Bioethanol yields from AH22:psacC grown on GJ (32.7[±4] mg mL(-1)) compared closely to those recently achieved (Martel et al., 2010) using enzymatically pre-hydrolysed GJ (36.8[±4] mg mL(-1)).

Linkage to nodal osteoarthritis: quantitative and qualitative analyses of data from a whole-genome screen identify trait-dependent susceptibility loci

OBJECTIVE

To identify susceptibility loci for nodal osteoarthritis.

METHODS

A genome screen at an average marker spacing of 9.29 cM was carried out on 558 people from 202 families, of whom 491 had nodal osteoarthritis. All genotyped people were graded for the incidence and severity of distal interphalangeal (DIP) nodes, and radiographs from 354 people were graded for joint-space narrowing (JSN) and osteophytes (OSTs). Age-regressed indices for DIP nodes, JSN and OSTs were calculated using these phenotypic data. Affected sibling pair (ASP) and quantitative trait analyses were carried out using MERLIN.

RESULTS

The data analysis identified suggestive linkage to loci on chromosomes 3 (for JSN and OST), 4 (for JSN), 8 (for DIP), 11 (for radiographic osteoarthritis) and 16 (for JSN). Both the ASP and quantitative analyses identified the loci on chromosomes 4 and 11. The loci on chromosomes 3 and 16 overlap with those previously identified for large-joint osteoarthritis. Of the loci identified by the quantitative analyses with the logarithm of the odds of linkage >1.5, two were linked to more than one trait, whereas nine were linked to single traits: one for DIP, six for JSN and two for OST.

CONCLUSION

The ASP and quantitative analyses of the cohort with nodal osteoarthritis suggest that multiple susceptibility loci for osteoarthritis influence the traits, which combine to form the osteoarthritis phenotype, and that these loci may not act exclusively on the joints of the hand.

A survey of information given during pregnancy by midwives to parents about neonatal unit care, whether or not the baby was likely to require such care

OBJECTIVE

To determine what information is given by midwives to parents in Scotland about care in a neonatal unit (a designated nursery offering special and/or intensive care to preterm and sick/vulnerable newborn babies), whether or not the baby is expected to require such care.

DESIGN

A survey using self-completion questionnaires.

SETTING

The questionnaires were sent to identified senior midwives in community and hospital settings in Scotland.

PARTICIPANTS

155 midwives, including 100 midwives involved in preparation for parenthood classes, 21 midwives responsible for hospital-based antenatal care, 17 midwives responsible for care in labour wards and 17 midwives responsible for care in neonatal units.

FINDINGS

Information about care in a neonatal unit was offered by all groups surveyed to all parents with whom the midwives were in contact. Eight rural community midwives did not routinely give information. Midwives involved in preparation for parenthood classes offered specific information at a median gestation of 28 weeks. The midwives addressed most suggested topics. The most commonly included topics were why babies require neonatal care and what problems they may have. The least commonly included topic was the long-term problems the baby may have. Several methods of teaching were used, especially discussion and question and answer, with a visit to the neonatal unit a common strategy. Few midwives shared information using audio-visual methods.

KEY CONCLUSIONS

The majority of midwives sampled offered information prenatally about neonatal unit care, with many tailoring this to the womanís needs.

IMPLICATIONS FOR PRACTICE

There should be consideration of the need to give information to all pregnant women and their partners, the most appropriate time for giving such information and the use of audio-visual teaching resources. The findings will inform further study of the extent to which such information meets the needs of parents.

Individualised care--from blueprint to practice

The first task was to develop a midwifery model, which initially meant establishing a philosophy of midwifery care. The next task was to consider documentation to support the system. The third part of the working group's remit was to educate their peers about the system. After implementation of the system, evaluation will be necessary.

Treadmill walking in old age may not reproduce the real life situation

OBJECTIVE

In a preliminary study in our laboratory, healthy elderly people had a higher heart rate during treadmill walking than during corridor walking at the same speed. The objective of this study was to determine whether this initial observation, (1) persisted after repeated testing, (2) was present in younger adults, (3) was due to wearing a mouthpiece during treadmill walking, or (4) was due to a change in gait.

DESIGN

A study of elderly and young volunteers undergoing repeated testing, with comparison of treadmill walking with corridor walking.

SETTING

The Royal Free Hospital School of Medicine.

PARTICIPANTS

Twelve healthy elderly (71-80 years) and 12 healthy young (21-37 years) volunteers.

MAIN OUTCOME MEASURES

Heart rate (beats/min) and step rate (steps/min) during comfortable self-paced corridor walking and during treadmill walking at the same speed.

MAIN RESULTS

The elderly subjects had higher heart rates during treadmill walking than during corridor walking at the same speed (mean difference = 6 beats/min, 95% Confidence Interval (CI) = 1 to 10). This difference increased (to a mean of 11 beats/min, 95% CI = 5 to 16) when a mouthpiece was worn on the treadmill. These differences persisted after repeated testing. The young subjects did not have higher heart rates on the treadmill, (with or without the mouthpiece). In both groups, step rate was lower (95% CI = -9 to -2, elderly; -5 to -2, young) during treadmill walking, corresponding to a 3% increase in stride length.

CONCLUSION

The heart rate response to treadmill walking in healthy elderly people may be less representative of the "real life" situation than in younger adults.

Prevalence and severity of morbidity among Gujarati Asian elders: a controlled comparison

Asian elders make relatively heavy use of health services: this may be due to higher levels of morbidity, but controlled comparisons have not been carried out. A comparison of the prevalence and severity of chronic diseases and use of health services of Asian and indigenous elders was made. A sample of 59 Gujarati Asians of mean age 62.9 years and 59 indigenous subjects of mean age 63.9 years of whom 42% (25 in each group) were female drawn from a general practice was studied. Asian subjects had a higher prevalence of diagnosed diseases, with the exception of chronic obstructive airways disease, but lower risk of falls and urinary incontinence. Asian subjects had higher life satisfaction scores and lower prevalence of depressed mood. Asian women were more likely to have had contact with primary care services. Both Asian men and women had more frequent hospital admissions, but similar levels of out-patient attendance. Body mass index, blood pressure and shoulder joint range of movement were similar for both Asians and the indigenous population. Asian subjects had significantly lower peak expiratory flow rates and hand grip strength. Asian elders have a higher risk of chronic diseases, but the impact of disease (indicated by life satisfaction, mood, and common disabilities) is less than among the indigenous population. Lower peak expiratory flow rates and grip strength among Asian elders are of concern since they may lead to premature arrival at age-related thresholds of physical capacity essential for independence in activities of daily living.

The effect of oral supplementation with L-carnitine on maximum and submaximum exercise capacity

Two trials were conducted to investigate the effects of L-carnitine supplementation upon maximum and submaximum exercise capacity. Two groups of healthy, untrained subjects were studied in double-blind cross-over trails. Oral supplementation of 2 g per day L-carnitine was used for 2 weeks in the first trial and the same dose but for 4 weeks in the second trial. Maximum and submaximum exercise capacity were assessed during a continuous progressive cycle ergometer exercise test performed at 70 rpm. In trial 1, plasma concentrations of lactate and beta-hydroxybutyrate were measured pre- and post-exercise. In trial 2, pre- and post-exercise plasma lactate were measured. The results of treatment with L-carnitine demonstrated no significant changes in maximum oxygen uptake (VO2max) or in maximum heart rate. In trial 1, there was a small improvement in submaximal performance as evidenced by a decrease in the heart-rate response to a work-load requiring 50% of VO2max. The more extensive trial 2 did not reproduce the significant result obtained in trial 1, that is, there was no significant decrease in heart rate at any given submaximal exercise intensity, under carnitine-supplemented conditions. Plasma metabolic concentrations were unchanged following L-carnitine, in both trials. It is concluded, that in contrast to other reports, carnitine supplementation may be of little benefit to exercise performance since the observed effects were small and inconsistent.