Summary Background Depression and anxiety have been linked to higher as well as lower reactivity to stressful circumstances. Large, population-based studies investigating the association between ...depression and anxiety, perceived and physiological stress responses are lacking. Methods We studied 725 men and women, aged 55–60 years, from a population-based cohort, who filled out the Hospital Anxiety and Depression Scale (HADS). We performed a standardized interview on medical history and lifestyle. We measured continuous blood pressure (BP) and heart rate (HR) reactivity, saliva cortisol reactivity and perceived stress during a psychological stress protocol. Results Albeit not statistically significant in all groups, systolic BP (SBP), diastolic BP (DBP), HR and cortisol reactivity to the psychological stress protocol were lower in those with mild-to-severe depression or anxiety symptoms and those ever clinically diagnosed with depression or anxiety, while perceived levels of stress were higher compared to those without depression or anxiety symptomatology. Maximum SBP, HR and cortisol stress responses significantly decreased and perceived stress scores significantly increased with increasing scores on the HADS depression subscale (HADS-D) and HADS anxiety subscale (HADS-A) (all P < 0.05). The same held for stress responses in relation to the total HADS score (all P < 0.05) and, in this case, the maximum DBP stress response was also significantly lower with an increasing HADS score ( P = 0.05). In addition, the maximum DBP stress response was significantly lower for those ever clinically diagnosed with depression ( P = 0.04). Adjusting for sex, use of anti-hypertensive medication, anti-depressant and anxiolytic medication, smoking, alcohol consumption, socio-economic status (SES) and body mass index (BMI) did not attenuate the results. Conclusion The present study results suggest that the biological stress response of middle-aged men and women who experienced depressed and anxious feelings does not completely correspond with how stressed they feel at that moment. Although differences were not substantial in all cases, response to a psychological stress protocol seemed to be decreased in the groups with experience of depressed and anxious feelings, while the perception of stress seemed to be increased.
Low nitrogen (N) content and retention in bauxite-processing residue sand (BRS) disposal areas pose a great challenge to the establishment of sustainable vegetation cover in this highly alkaline ...environment. The budget and fate of applied N in BRS and its potential environmental impacts are largely unknown. We investigated the effect of combined application of biochars aged acidic (AC) vs alkaline pine (PC) and di-ammonium phosphate (DAP) fertiliser on ammonia (NH3) volatilisation, nitrous oxide (N2O) emission and N retention in a 116-day glasshouse study. The application of AC to BRS decreased pH (≈0.5 units) in BRS, while PC biochar increased pH (≈0.3 units). The application of AC reduced NH3 volatilisation by ca. 80%, while PC by ca. 25%. On the other hand, the AC treatment increased N2O emission by 5 folds. However, the N loss via N2O emission in the AC treatment only accounted for ca. 0.4% of applied N. The reduction in BRS pH and increased retention of mineral N due to the presence of oxygen-containing (phenolic and carboxylic) functional groups in AC may be responsible for reduced NH3 volatilisation and increased N2O emission. This study has highlighted the potential of biochar (particularly aged biochar) in improving N retention and minimising environmental impacts in highly alkaline environments.
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•Effects of biochar and mineral fertiliser studied on nitrogen fate in bauxite residue.•Aged acidic biochar decreased, while alkaline pine biochar increased pH of residue.•Aged biochar showed high oxygen-containing functional groups and adsorption capacity.•Added biochar decreased ammonia volatilisation while increased nitrous oxide emission.•Aged biochar increased nitrogen retention, plant nitrogen concentration and uptake.
Abstract Background Previous studies suggest a link between depression, anxiety and cardiovascular disease (CVD). The aim of the study was to determine the relationship between depressive and anxiety ...symptoms and CVD in a population based cohort. Methods In total 1578 men and 1,417 women from the Hertfordshire Cohort Study were assessed for CVD at baseline and after 5.9±1.4 years. Depressive and anxiety symptoms were measured using the HADS scale. Results Baseline HAD-D score, but not HAD-A, was significantly associated with baseline plasma triglycerides, glucose and insulin resistance (men only) and HDL cholesterol (women only). After adjustment for CVD risk factors, higher baseline HAD-D scores were associated with increased odds ratios for CVD (men: 1.162 95% CI 1.096–1.231; women: 1.107 1.038–1.181). Higher HAD-A scores associated with increased CVD in men only. High HAD-D scores predicted incident CVD (adjusted OR 1.130 1.034–1.235), all-cause mortality (adjusted HR 1.081, 1.012–1.154) and cardiovascular mortality (adjusted HR 1.109 1.002–1.229) in men but not in women. Limitations The use of a self-report measure of depressive and anxiety symptoms, ‘healthy’ responder bias and the low number of cardiovascular events are all limitations. Conclusions Depressive and anxiety symptoms are commoner in people with CVD. These symptoms are independent predictors of CVD in men. Although HAD-D score was significantly associated with several cardiovascular risk factors, this did not fully explain the association between HAD-D and CVD.
Colonial organisms host a large diversity of symbionts (collectively, parasites, mutualists, and commensals) that use vertical transmission (from parent colony to offspring colony) and/or horizontal ...transmission to disperse between host colonies. The early life of some colonies, characterized by the dispersal and establishment of solitary individuals, may constrain vertical transmission and favor horizontal transmission between large established colonies. We explore this possibility with the miniature cockroach Attaphila fungicola, a symbiont of leaf‐cutter ants and the mutualist fungal gardens they cultivate. The early life of a leaf‐cutter colony is characterized by the dispersal of a female alate (winged “queen”) carrying a fungal pellet, and the subsequent establishment of a foundress (workerless “queen”) raising her incipient fungal garden and colony. Roaches hitchhike on female alates during leaf‐cutter nuptial flights, which strongly suggests that roaches are vertically transmitted to foundresses and their incipient colonies; however, weak compatibility between roaches and incipient gardens may constrain roach vertical transmission. Reciprocally, opportunities for horizontal transmission between large established colonies with abundant fungal gardens may weaken selection against roach‐induced harm (virulence) of incipient gardens. We use a laboratory experiment, behavioral observations, field surveys, and a transmission model to estimate the effect roaches have on the survivorship of incipient gardens and the frequency of roach vertical transmission. Contrary to traditional assumptions, our results indicate that roaches harm incipient gardens and predominantly use horizontal transmission between established leaf‐cutter colonies. Ultimately, “costs of generalism” associated with infecting disparate stages of a host's lifecycle (e.g., incipient vs. established colonies) may constrain the vertical transmission of roaches and a broad range of symbionts.
It may be costly for symbionts to infect the "newborn" solitary stages of colonial hosts, constraining vertical transmission and favoring horizontal transmission between larger established host colonies. We explore this possibility using a miniature symbiotic cockroach of leaf‐cutter ants and their fungal gardens. Our study demonstrates that accounting for host colony lifecycle heterogeneity is important for understanding symbiont transmission dynamics and evolution.
Enhanced efficiency fertilisers (EEF) may reduce nitrogen (N) losses and improve uptake efficiency through synchronising N release with in-season plant requirements. We hypothesised that EEF formed ...via matrix encapsulation in biodegradable polymers will improve N use efficiency when compared to conventional urea fertiliser. This hypothesis was investigated for two biodegradable polymer matrices: polyhydroxyalkanoate (PHA), containing 11.6% urea (by mass), and polybutylene-adipate-co-terephthalate (PBAT), containing either 19.4 or 32.7% urea; and two contrasting soil types: sand and clay. Nitrogen availability and form was investigated under leaching conditions (water) with a growth accelerator pot experiment involving a horticultural crop and novel non-destructive three-dimensional scanning to measure in-season biomass development. The PBAT 32.7% formulation enabled greater above ground biomass production at both 50 and 100 kg N ha−1 equivalent application rates compared to conventional urea. For the sandy soil, plant scanning indicated that improved uptake performance with PBAT 32.7% was probably the result of greater N availability after 25 days than for conventional urea. Two of the encapsulated formulations (PHA and PBAT 19.4%) tended to decrease nitrogen leaching losses relative to urea (P < 0.05 for the red clay soil). However, decreased N leaching loss was accompanied by poorer N uptake performance, indicative of N being less available in these biopolymer formulations. A snapshot of nitrous oxide emissions collected during peak nitrate concentration (prior to planting and leaching) suggested that the biopolymers promoted N loss via gaseous emission relative to urea in the sandy soil (P < 0.05), and carbon dioxide emissions data suggested that biopolymer-carbon increased microbial activity (P < 0.1). Controlled testing of N release in water was a poor predictor of biomass production and leaching losses. The diverse behaviours of the tested formulations present the potential to optimise biopolymers and their N loadings by taking into account soil and environmental factors that influence the efficient delivery of N to target crops. The greater N uptake efficiency demonstrated for the PBAT 32.7% formulation confirms our hypothesis that matrix encapsulation can enable better synchronisation of N release with crop requirements and decrease leaching losses.
•We tested urea, co-extruded in biodegradable polymers, as novel N fertiliser.•Quantification of N leaching, nitrous oxide emission, and weekly crop biomass.•Urea in PBAT improved N uptake (up to 21%, 50 kg of N ha−1) over conventional urea.•Improved synchronisation of N supply with crop requirements increased efficiency.•Improving uptake, leaching, and nitrous oxide emission can be opposing goals.
The three-dimensional conformation of a protein is an important property and plays a key role in its biological activity. We show here that ion mobility-mass spectrometry (IM-MS) can be used to ...detect conformational changes in the protein ubiquitin in the gas phase induced by reaction with the anticancer drug cisplatin. The primary adduct was ubiquitin-{Pt(NH
3)
2} under denaturing conditions. Up to three different conformations appear to be generated upon platination depending on the charge state. The collision cross-sections (Ω) for each conformation indicate that the conformations of the platinated protein are contracted in size compared with unmodified ubiquitin with generally smaller Ω values. Ion mobility-tandem MS allowed determination of the platinum binding site without a requirement for prior chromatographic separation. A rapid 30-min digestion of cisplatin-modified ubiquitin with trypsin allowed the platination site to be identified as the N-terminal methionine following low-energy collision-induced dissociation (CID) studies of the modified peptide. The data were generated using a Traveling-Wave based ion mobility-MS approach. Such cisplatin-induced shape changes may have a significant effect on its function in vivo. This work highlights the usefulness of the ion-mobility mass spectrometry technique for shedding new light on such protein interactions.
Ion mobility-MS studies show that platination of the N-terminal methionine of ubiquitin with the anticancer drug cisplatin causes protein conformational changes.
Aims/hypothesis
We aimed to characterise the immunogenic background of insulin-dependent diabetes in a resource-poor rural African community. The study was initiated because reports of low ...autoantibody prevalence and phenotypic differences from European-origin cases with type 1 diabetes have raised doubts as to the role of autoimmunity in this and similar populations.
Methods
A study of consecutive, unselected cases of recently diagnosed, insulin-dependent diabetes (
n
= 236, ≤35 years) and control participants (
n
= 200) was carried out in the ethnic Amhara of rural North-West Ethiopia. We assessed their demographic and socioeconomic characteristics, and measured non-fasting C-peptide, diabetes-associated autoantibodies and
HLA-DRB1
alleles. Leveraging genome-wide genotyping, we performed both a principal component analysis and, given the relatively modest sample size, a provisional genome-wide association study. Type 1 diabetes genetic risk scores were calculated to compare their genetic background with known European type 1 diabetes determinants.
Results
Patients presented with stunted growth and low BMI, and were insulin sensitive; only 15.3% had diabetes onset at ≤15 years. C-peptide levels were low but not absent. With clinical diabetes onset at ≤15, 16–25 and 26–35 years, 86.1%, 59.7% and 50.0% were autoantibody positive, respectively. Most had autoantibodies to GAD (GADA) as a single antibody; the prevalence of positivity for autoantibodies to IA-2 (IA-2A) and ZnT8 (ZnT8A) was low in all age groups. Principal component analysis showed that the Amhara genomes were distinct from modern European and other African genomes.
HLA-DRB1*03:01
(
p
= 0.0014) and
HLA-DRB1*04
(
p
= 0.0001) were positively associated with this form of diabetes, while
HLA-DRB1*15
was protective (
p
< 0.0001). The mean type 1 diabetes genetic risk score (derived from European data) was higher in patients than control participants (
p
= 1.60 × 10
−7
). Interestingly, despite the modest sample size, autoantibody-positive patients revealed evidence of association with SNPs in the well-characterised MHC region, already known to explain half of type 1 diabetes heritability in Europeans.
Conclusions/interpretation
The majority of patients with insulin-dependent diabetes in rural North-West Ethiopia have the immunogenetic characteristics of autoimmune type 1 diabetes. Phenotypic differences between type 1 diabetes in rural North-West Ethiopia and the industrialised world remain unexplained.
Biofiltration systems are becoming a popular stormwater treatment device in water sensitive urban design for the removal of fine particulate and dissolved pollutants from stormwater. However, there ...is limited published data on the effectiveness of these systems for nutrient removal. We constructed biofiltration mesocosms to assess nutrient removal (nitrogen, phosphorus and carbon) under experimental conditions. Different types of media were compared (gravel, sand, and sandy-loam) in vegetated and non-vegetated mesocosms (six treatments in total). Five plant species were used. Vegetated sand and vegetated sandy-loam provided the best overall treatment. Vegetated mesocosms were very effective in removing nitrogen (63-77% removal) and phosphorus (85-94% removal) from synthetic stormwater, and removed substantially more nutrients than the non-vegetated treatments. All treatments removed a substantial portion of the carbon from the stormwater (28-66%). When flushed with tap water, nitrogen and phosphorus were retained by the vegetated mesocosms, but leached from the non-vegetated mesocosms. Plant growth was most vigorous in the sandy-loam media, indicating that this is a good growth media, even without the addition of organic matter.
We experimentally demonstrate a Raman-Assisted Fibre Optical Parametric Amplifier (RA-FOPA) with 20dB net gain using wavelength division multiplexed signals. We report amplification of 10x58Gb/s ...100GHz-spaced QPSK signals and show that by appropriate tuning of the parametric pump power and frequency, gain improvement of up to 5dB can be achieved for the RA-FOPA compared with combined individual contributions from the parametric and Raman pumps. We compare the RA-FOPA with an equivalent-gain conventional FOPA and find that four-wave mixing crosstalk is substantially reduced by up to 5.8 ± 0.4dB using the RA-FOPA. Worst-case performance penalty of the RA-FOPA is found to be only 1.0 ± 0.2dB over all measured OSNRs, frequencies and input powers, making it an attractive proposal for future communications systems.
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