ABSTRACT
Research on perceptions of sexual interest has documented the tendency for men to overperceive sexual interest (i.e., to perceive a social signal as indicating more sexual intent than the actor intended). However, this work has almost exclusively focused upon these dynamics among heterosexual individuals. Thus, the current set of studies aimed to understand how perceptions of sexual interest manifest among lesbian, gay, and bisexual (LGB) women and men. In Study 1 (N = 85), LGB women and men nominated behaviors that signal sexual intent. Using an act nomination approach, LGB women and men tended to nominate behaviors similar to those nominated by heterosexual women and men. In Study 2 (N = 43), gay men reported acts that were representative of their own and other gay men's sexual interest. Consistent with previous work-by comparing perceived self-reported versus others' sexual intent when engaging in specific behaviors-we found no evidence for a sexual overperception bias in gay men, albeit in a small field study. In Study 3 (N = 307), using a gender-by-sexual orientation design, heterosexual and LGB women and men reported previous experiences in which their friendliness was sexually misperceived. Bisexual women were less likely than other groups to report their friendliness being misinterpreted as sexual by other bisexual women and/or lesbians. Additionally, across all genders and sexual orientations, participants reported feelings of indifference, awkwardness and embarrassment when being misperceived. Ultimately, the current studies' results provide broader insight into the nature of sexual overperception among LGB populations.
Subject(s)
Homosexuality, Female , Sexual and Gender Minorities , Female , Humans , Male , Sexual Behavior , Bisexuality , HeterosexualityABSTRACT
Background: Sociosexuality-attitudes, behaviors, and desires related to casual sex-partly predicts drinking behavior in both men and women because drinking is thought to facilitate interactions that lead to casual sex. It follows that sociosexuality would predict drinking intake (e.g., quantity consumed)-but perhaps not drinking consequences (e.g., blacking out)-on the premise that drinking large quantities with high frequency (but not to such high degrees/levels of intoxication that negative consequences occur) would facilitate casual sex. Objectives: This set of studies evaluated whether baseline measures of sociosexuality predict drinking intake (i.e., frequency, quantity, and binge drinking) but not experiencing blacking out at follow-up in two samples (Study 1, N = 172; Study 2, N = 1,038) of college-aged men. Results: As predicted, men's sociosexuality prospectively predicted drinking frequency, quantity, and binge drinking. Contrary to our predictions, men's sociosexuality also predicted blacking out. Conclusions: College men's drinking interventions should be tailored to high-risk groups and consider individual differences like sociosexuality.
Subject(s)
Alcohol Drinking , Binge Drinking , Humans , Male , Young Adult , Alcohol Drinking/psychology , Binge Drinking/psychology , Sexual Behavior/psychology , Adult , Adolescent , Alcohol Drinking in College/psychology , Universities , Students/psychologyABSTRACT
Despite their significant impact, comprehensive screenings and detailed analyses of per- and polyfluoroalkyl substance (PFAS) binding strengths at the orthosteric and allosteric sites of NRs are currently lacking. This study addresses this gap by focusing on the binding interaction analysis of both common and uncommon PFAS with the nuclear receptors (NRs) vitamin D receptor (VDR), peroxisome proliferator-activated receptor gamma (PPARγ), pregnane X receptor (PXR), and estrogen receptor alpha (ERα). Advanced docking simulations were used to screen 9507 PFAS chemicals at the orthosteric and allosteric sites of PPARγ, PXR, VDR, and ERα. All receptors exhibited strong binding interactions at the orthosteric and allosteric site with a significant number of PFAS. We verified the accuracy of the docking protocol through multiple docking controls and validations. A mixture modeling analysis indicates that PFAS can bind in various combinations with themselves and endogenous ligands simultaneously, to disrupt the endocrine system and cause carcinogenic responses. These findings reveal that PFAS can interfere with nuclear receptor activity by displacing endogenous or native ligands by binding to the orthosteric and allosteric sites. The purpose of this study is to explore the mechanisms through which PFAS exert their endocrine-disrupting effects, potentially leading to more targeted therapeutic strategies. Importantly, this study is the first to explore the binding of PFAS at allosteric sites and to model PFAS mixtures at nuclear receptors. Given the high concentration and persistence of PFAS in humans, this study further emphasizes the urgent need for further research into the carcinogenic mechanisms of PFAS and the development of therapeutic strategies that target nuclear receptors.
Subject(s)
Fluorocarbons , Molecular Docking Simulation , Protein Binding , Receptors, Cytoplasmic and Nuclear , Receptors, Cytoplasmic and Nuclear/metabolism , Receptors, Cytoplasmic and Nuclear/chemistry , Humans , Fluorocarbons/chemistry , Fluorocarbons/metabolism , Binding Sites , Ligands , Allosteric Site , Pregnane X Receptor/metabolism , Pregnane X Receptor/chemistry , Endocrine Disruptors/chemistry , Endocrine Disruptors/metabolism , Endocrine Disruptors/pharmacology , Receptors, Calcitriol/metabolism , Receptors, Calcitriol/chemistryABSTRACT
Small watercourses are essential contributors to catchment water quality, but they continue to suffer degradation across Europe. A results-based agri-environment scheme, aimed at improving watercourse quality in Ireland, developed a rapid drainage assessment to identify point source risks. The assessment uses a scoring system based on visual indicators of nutrient and sediment risk, linking the outcomes to farmer payments. To understand how this novel drainage risk assessment relates to instream watercourse quality, we used three macroinvertebrate-based biotic indices (Q-value, Small Stream Impact Score and Proportion of Sediment Sensitive Invertebrates). Macroinvertebrate kick-sampling and physiochemical analysis were completed in May and July 2021 for 12 'At Risk' and 12 'Not at Risk' small watercourses as identified by the results-based scheme. Results show that the scheme's drainage risk assessment can identify point source risks but we found it does not directly reflect local instream quality as assessed by the biotic indices. Unexpectedly, the biotic indices showed watercourse degradation in 58% of the upstream (control) sampling points, indicating impacts not captured by the drainage risk assessment. Small watercourses displayed high heterogeneity, with significant species turnover between the sampling months. The Small Stream Impact Score was less influenced by temporal change than the Q-value index. There was a significant relationship between instream watercourse quality and sedimentation, as quantified by the Proportion of Sediment Sensitive Invertebrates. Including a measurement of instream sedimentation in the drainage assessments would improve the identification of risks and management. These results show that by linking farmer payments to the drainage risk assessments results-based payment schemes could positively contribute to improving catchment scale watercourse quality, but further work is required to capture wider sources of freshwater impacts.
Subject(s)
Environmental Monitoring , Invertebrates , Animals , Environmental Monitoring/methods , Water Quality , Rivers , EuropeABSTRACT
ISSUE ADDRESSED: E-scooters are sought after for their cost-effectiveness, sustainability, and efficiency in urban transportation. However, this popularity has been accompanied by a surge in injuries, prompting a deeper investigation into the factors influencing risk perceptions among e-scooter users. METHODS: Using a qualitative approach, we conducted 19 interviews with those who attended an emergency department as a result of e-scooter injury. We aimed to understand the psychosocial effects of these incidents and employed thematic analysis to discern recurrent patterns in participants' experiences, focusing on alterations in daily life, community response, perception shifts, and avenues to enhance safety awareness. RESULTS: The findings underscored significant disruptions to daily life due to injuries, demonstrating enduring impacts on lifestyle and wellbeing. Participants exhibited a perceptual shift, transitioning from perceiving e-scooters as enjoyable to viewing them as dangerous. Recommendations for enhancing safety awareness included accessible and clear safety education, pre-ride briefings, real-time safety guidance, temporal rental restrictions, and mandatory breathalysers before e-scooter use. CONCLUSIONS: The study underscores the importance of considering not only the individual experiences and perceptions of e-scooter injuries but also the broader social context, including the night-time economy. Leveraging peer narratives and community engagement is vital to reshape risk perceptions and promote harm reduction messages. SO WHAT?: A comprehensive approach through proactive interventions and robust educational strategies is essential to foster responsible e-scooter usage and prioritise public safety.
ABSTRACT
Subtle variations in stable isotope ratios at natural abundance are challenging to measure but can yield critical insights into biological, physical, and geochemical processes. Well-established methods, particularly multicollector, gas-source, or plasma isotope ratio mass spectrometry, are the gold standard for stable isotope measurement, but inherent limitations in these approaches make them ill-suited to determining site-specific and multiply substituted isotopic abundances of all but a few compounds or to characterizing larger intact molecules. Fourier transform mass spectrometry, namely, Orbitrap mass spectrometry, has recently demonstrated the ability to measure natural abundance isotope ratios with chemically informative accuracy and precision. Here, we report the first use of Fourier transform ion cyclotron resonance mass spectrometry for the accurate (<1) and precise (<1 standard error) simultaneous determination of δ13C and δ15N in caffeine isotopologues and provide a discussion of the critical instrumental parameters necessary to make such measurements. We further report the ability to make these measurements with online liquid chromatography, expanding the ability of this technique to explore mixtures in the future.
ABSTRACT
Psychiatric patients are prone to mental health deterioration during the Covid-19 pandemic. Little is known about suicidality in psychiatric patients during the Covid-19 pandemic. This study is a retrospective chart review of psychiatric emergency department (pED) presentations with present or absent suicidality (5634 pED attendances, 4110 patients) in an academic pED in Berlin, Germany. Poisson regression analysis was performed on the effect of Covid-19 period on suicidality (suicidal ideation (SI), suicide plans (SP) or suicide attempt (SA)) during the first (3/2/2020-5/24/2020 "first-wave") and second (9/15/2020-3/1/2021 "second-wave") wave of the Covid-19 pandemic compared to the same periods one year earlier. During the first-wave the number of pED visits per person with SI, SP and SA was higher compared to one year earlier (SI RR = 1.614; p = 0.016; SP RR = 2.900; p = 0.004; SA RR = 9.862; p = 0.003). SI and SP were predicted by interaction between substance use disorder (SUD) and second-wave (SI RR = 1.305, p = 0.043; SP RR = 1.645, p = 0.018), SA was predicted by interaction between borderline personality disorder (BPD) and second-wave (RR = 7.128; p = 0.012). Suicidality increased during the first-wave of Covid-19 pandemic in our sample. In the second-wave this was found in patients with SUD and BPD. These patients may be at particular risk of suicidality during the Covid-19 pandemic.
Subject(s)
COVID-19 , Substance-Related Disorders , Suicide , Humans , Suicidal Ideation , Retrospective Studies , Pandemics , COVID-19/epidemiology , Substance-Related Disorders/epidemiology , Emergency Service, HospitalABSTRACT
There is evidence that racial discrimination at different levels has a major impact on mental health over the whole life span. It is related generally to poor health, with the relationship being particularly strong for mental health. All forms of structural, institutionalised, interpersonal and internalised racism as well as the cumulative impact of intersectional discrimination appear to be linked to mental health and well-being. Studies also show links between effects of racial discrimination and neurophysiology especially on the brain volume. All forms of racism need to be addressed in inter- and transdisciplinary ways in order to dismantle racial discrimination. This review provides an overview of these interconnections.
Subject(s)
Mental Health , Racism , Humans , Racism/psychologyABSTRACT
Perceived discrimination has a significant negative impact on indices of mental health. One potential buffering factor in this is psychological resilience, which encompasses the ability to recover from or adapt successfully to adversity and use coping strategies, such as positive reappraisal of adverse events. This study examines the role of resilience as well as social support in buffering these effects in groups of migrants both with and without local residence permits. We conducted a non-experimental observational study with a cross-sectional design, collecting a variety of health variables in migrant groups in a naturalistic setting, during the COVID-19 period. The total sample consisted of 201 subjects, 88 of whom had a German residence title and 113 did not. These two groups were compared on the following variables of interest: social support, resilience, discrimination, and general mental health. There was no evidence for a difference in mental health between migrants with and without citizenship. However, our results suggested that migrants without citizenship reported less social support, less resilience, and more discrimination, which continued to have a distinct effect on mental health beyond resilience and social support. Psychological resilience mediated the link between social support and mental health, as well as being related to the perception of discrimination in the migrant group without citizenship. In conclusion, our models of migrants with and without citizenship showed that resilience specifically directly affected perceived discrimination in those without citizenship. The high levels of discrimination and lack of social support, particularly in the migrant group without citizenship, are concerning and suggest a focus for future interventions.
Subject(s)
COVID-19 , Resilience, Psychological , Transients and Migrants , Humans , Mental Health , Cross-Sectional Studies , Citizenship , Social SupportABSTRACT
In the flash-lag illusion (FLI), the position of a flash presented ahead of a moving bar is mislocalized, so the flash appears to lag the bar. Currently, it is not clear whether this effect is due to early perceptual-related neural processes such as motion extrapolation or reentrant processing, or due to later feedback processing relating to postdiction, i.e., retroactively altered perception. We presented 17 participants with the FLI paradigm while recording EEG. A central flash occurred either 51 ms ("early") or 16 ms ("late") before the bar moving from left to right reached the screen center. Participants judged whether the flash appeared to the right ("no flash lag illusion") or to the left ("flash-lag illusion") of the bar. Using single-trial linear modeling, we examined the influence of timing ("early" vs. "late") and perception ("illusion" vs. "no illusion") on flash-evoked brain responses and estimated the cortical sources underlying the FLI. An earlier frontal and occipital component (200-276 ms) differentiated time-locked early vs. late stimulus presentation, indicating that early evoked brain responses reflect feature encoding in the FLI. Perception of the FLI was associated with a late window (368-452 ms) in the ERP, with larger deflections for illusion than no illusion trials, localized to the left inferior occipital gyrus. This suggests a postdiction-related reconstruction of ambiguous sensory stimulation involving late processes in the occipito-temporal cortex, previously associated with temporal integration phenomena. Our findings indicate that perception of the FLI relies on an interplay between ongoing stimulus encoding of the moving bar and feedback processing of the flash, which takes place at later integration stages.
Subject(s)
Cerebral Cortex/physiology , Electroencephalography , Evoked Potentials/physiology , Illusions/physiology , Space Perception/physiology , Visual Perception/physiology , Adult , Cerebral Cortex/diagnostic imaging , Female , Humans , Male , Middle Aged , Young AdultABSTRACT
Differences in attitudes on social issues such as abortion, immigration and sex are hugely divisive, and understanding their origins is among the most important tasks facing human behavioural sciences. Despite the clear psychological importance of parenthood and the motivation to provide care for children, researchers have only recently begun investigating their influence on social and political attitudes. Because socially conservative values ostensibly prioritize safety, stability and family values, we hypothesized that being more invested in parental care might make socially conservative policies more appealing. Studies 1 (preregistered; n = 376) and 2 (n = 1924) find novel evidence of conditional experimental effects of a parenthood prime, such that people who engaged strongly with a childcare manipulation showed an increase in social conservatism. Studies 3 (n = 2610, novel data from 10 countries) and 4 (n = 426 444, World Values Survey data) find evidence that both parenthood and parental care motivation are associated with increased social conservatism around the globe. Further, most of the positive association globally between age and social conservatism is accounted for by parenthood. These findings support the hypothesis that parenthood and parental care motivation increase social conservatism.
Subject(s)
Cross-Cultural Comparison , Motivation , Attitude , Child , Female , Humans , Politics , Pregnancy , Surveys and QuestionnairesABSTRACT
Studies on schizophrenia (SCZ) and aberrant multisensory integration (MSI) show conflicting results, which are potentially confounded by attention deficits in SCZ. To test this, we examined the interplay between MSI and intersensory attention (IA) in healthy controls (HCs) (N = 27) and in SCZ (N = 27). Evoked brain potentials to unisensory-visual (V), unisensory-tactile (T), or spatiotemporally aligned bisensory VT stimuli were measured with high-density electroencephalography, while participants attended blockwise to either visual or tactile inputs. Behaviorally, IA effects in SCZ, relative to HC, were diminished for unisensory stimuli, but not for bisensory stimuli. At the neural level, we observed reduced IA effects for bisensory stimuli over mediofrontal scalp regions (230-320 ms) in SCZ. The analysis of MSI, using the additive approach, revealed multiple phases of integration over occipital and frontal scalp regions (240-364 ms), which did not differ between HC and SCZ. Furthermore, IA and MSI effects were both positively related to the behavioral performance in SCZ, indicating that IA and MSI mutually facilitate bisensory stimulus processing. Multisensory processing could facilitate stimulus processing and compensate for top-down attention deficits in SCZ. Differences in attentional demands, which may be differentially compensated by multisensory processing, could account for previous conflicting findings on MSI in SCZ.
Subject(s)
Schizophrenia , Acoustic Stimulation/methods , Auditory Perception/physiology , Electroencephalography/methods , Humans , Photic Stimulation/methods , Reaction Time/physiology , Visual Perception/physiologyABSTRACT
Child sexual abuse offences (CSOs) represent a severe ethical and socioeconomic burden for society. Juveniles with a sexual preference for prepubescent children (PP) commit a large percentage of CSOs, but have been widely neglected in neuroscience research. Aberrant neural responses to face stimuli have been observed in men with pedophilic interest. Thus far, it is unknown whether such aberrations exist already in PP. A passive face-viewing paradigm, including the presentation of child and adult faces, was deployed and high-density electroencephalography data were recorded. The study group comprised 25 PP and the control group involved 22 juveniles with age-adequate sexual preference. Attractiveness ratings and evoked brain responses were obtained for the face stimuli. An aberrant pattern of attractiveness ratings for child vs. adult faces was found in the PP group. Moreover, elevated occipital P1 amplitudes were observed for adult vs. child faces in both groups. At longer latency (340-426 ms), a stronger negative deflection to child vs. adult faces, which was source localized in higher visual, parietal and frontal regions, was specifically observed in the PP group. Our study provides evidence for enhanced neural processing of child face stimuli in PP, which might reflect elevated attention capture of face stimuli depicting members from the sexually preferred age group. This study expands our understanding of the neural foundations underlying sexual interest in prepubescent children and provides a promising path for the uncovering of objective biomarkers of sexual responsiveness to childlike body schemes in juveniles.
Subject(s)
Pedophilia , Sex Offenses , Adult , Attention , Child , Electroencephalography , Humans , Male , Sexual BehaviorABSTRACT
We observed COVID-19 concern during goal pursuit data collection, where some undergraduates self-reported COVID-19 specific goals. Thus, we analyzed the individual difference in students who self-reported COVID-19 specific goals in this current exploratory study. The results revealed (N = 496) that there were no differences in those who reported COVID-19 goals with their self-reporting of the Five-Factor Model. Additionally, participant's most reported goal was to 1) not contract COVID-19, 2) be social during COVID-19, and 3) follow health and safety protocols. This study provides researchers with both qualitative and quantitative evidence about college students' concern with COVID-19.
ABSTRACT
KEY POINTS: Muscle glycogen and intramuscular triglycerides (IMTG, stored in lipid droplets) are important energy substrates during prolonged exercise. Exercise-induced changes in lipid droplet (LD) morphology (i.e. LD size and number) have not yet been studied under nutritional conditions typically adopted by elite endurance athletes, that is, after carbohydrate (CHO) loading and CHO feeding during exercise. We report for the first time that exercise reduces IMTG content in both central and peripheral regions of type I and IIa fibres, reflective of decreased LD number in both fibre types whereas reductions in LD size were exclusive to type I fibres. Additionally, CHO feeding does not alter subcellular IMTG utilisation, LD morphology or muscle glycogen utilisation in type I or IIa/II fibres. In the absence of alterations to muscle fuel selection, CHO feeding does not attenuate cell signalling pathways with regulatory roles in mitochondrial biogenesis. ABSTRACT: We examined the effects of carbohydrate (CHO) feeding on lipid droplet (LD) morphology, muscle glycogen utilisation and exercise-induced skeletal muscle cell signalling. After a 36 h CHO loading protocol and pre-exercise meal (12 and 2 g kg-1 , respectively), eight trained males ingested 0, 45 or 90 g CHO h-1 during 180 min cycling at lactate threshold followed by an exercise capacity test (150% lactate threshold). Muscle biopsies were obtained pre- and post-completion of submaximal exercise. Exercise decreased (P < 0.01) glycogen concentration to comparable levels (â¼700 to 250 mmol kg-1 DW), though utilisation was greater in type I (â¼40%) versus type II fibres (â¼10%) (P < 0.01). LD content decreased in type I (â¼50%) and type IIa fibres (â¼30%) (P < 0.01), with greater utilisation in type I fibres (P < 0.01). CHO feeding did not affect glycogen or IMTG utilisation in type I or II fibres (all P > 0.05). Exercise decreased LD number within central and peripheral regions of both type I and IIa fibres, though reduced LD size was exclusive to type I fibres. Exercise induced (all P < 0.05) comparable AMPKThr172 (â¼4-fold), p53Ser15 (â¼2-fold) and CaMKIIThr268 phosphorylation (â¼2-fold) with no effects of CHO feeding (all P > 0.05). CHO increased exercise capacity where 90 g h-1 (233 ± 133 s) > 45 g h-1 (156 ± 66 s; P = 0.06) > 0 g h-1 (108 ± 54 s; P = 0.03). In conditions of high pre-exercise CHO availability, we conclude CHO feeding does not influence exercise-induced changes in LD morphology, glycogen utilisation or cell signalling pathways with regulatory roles in mitochondrial biogenesis.
Subject(s)
AMP-Activated Protein Kinases , Lipid Droplets , Dietary Carbohydrates , Exercise Tolerance , Humans , Male , Muscle, Skeletal , Tumor Suppressor Protein p53ABSTRACT
BACKGROUND: The outbreak of the COVID-19 disease and the rapid spread of the inducing coronavirus SARS-CoV2 threatens not only people's physical health but also their mental health. Its influence on incidence and course of existing illnesses in the psychiatric outpatient sector in Germany is still unknown. METHODS: The medical reports of 682 persons in psychiatric treatment were retrospectively investigated, regarding their subjective response to this pandemic and its clinical relevance. RESULTS: Of the patients 60.5% (nâ¯= 378) experienced greater psychological stress, 14.5% (nâ¯= 99) reported fear of the SARS-CoV2 and the possible danger of infection, 25.5% (nâ¯= 174) reported fear resulting from the protective measures taken (lock down) and 4.3% (nâ¯= 29) reported fear of both. This differed significantly across diagnoses: people with anxiety disorders reported significantly greater stress as well as greater fear of the virus, whereas people with psychoses were significantly less affected than the other patients. Of the participants 43.7% (nâ¯= 132) were so strongly affected that acute treatment had to be implemented and 6.0% (nâ¯= 18) had to be referred to inpatient care. DISCUSSION: People with mental illnesses are particularly vulnerable to the psychological strain of the COVID-19 pandemic. Long-term studies on the further course of disease will be necessary. Additional studies that test interventions to build resilience in this population will also be needed.
Subject(s)
COVID-19 , Pandemics , Anxiety , Communicable Disease Control , Germany/epidemiology , Humans , Retrospective Studies , SARS-CoV-2 , Stress, Psychological/epidemiologyABSTRACT
The Ebola virus disease outbreak in west Africa has prompted significant progress in responding to the clinical needs of patients affected by emerging infectious disease outbreaks. Among the noteworthy successes of vaccine trials, and the commendable efforts to implement clinical treatment trials during Ebola outbreaks, we should also focus on strengthening the collection and curation of epidemiological and observational data that can improve the conception and design of clinical research.
Subject(s)
Epidemics , Hemorrhagic Fever, Ebola , Africa, Western/epidemiology , Disease Outbreaks/prevention & control , Hemorrhagic Fever, Ebola/epidemiology , Hemorrhagic Fever, Ebola/prevention & control , HumansABSTRACT
The upper green layer of the chlorophototrophic microbial mats associated with the alkaline siliceous hot springs of Yellowstone National Park consists of oxygenic cyanobacteria (Synechococcus spp.), anoxygenic Roseiflexus spp., and several other anoxygenic chlorophototrophs. Synechococcus spp. are believed to be the main fixers of inorganic carbon (Ci), but some evidence suggests that Roseiflexus spp. also contribute to inorganic carbon fixation during low-light, anoxic morning periods. Contributions of other phototrophic taxa have not been investigated. In order to follow the pathway of Ci incorporation into different taxa, mat samples were incubated with [13C]bicarbonate for 3 h during the early-morning, low-light anoxic period. Extracted proteins were treated with trypsin and analyzed by mass spectrometry, leading to peptide identifications and peptide isotopic profile signatures containing evidence of 13C label incorporation. A total of 25,483 peptides, corresponding to 7,221 proteins, were identified from spectral features and associated with mat taxa by comparison to metagenomic assembly sequences. A total of 1,417 peptides, derived from 720 proteins, were detectably labeled with 13C. Most 13C-labeled peptides were derived from proteins of Synechococcus spp. and Roseiflexus spp. Chaperones and proteins of carbohydrate metabolism were most abundantly labeled. Proteins involved in photosynthesis, Ci fixation, and N2 fixation were also labeled in Synechococcus spp. Importantly, most proteins of the 3-hydroxypropionate bi-cycle for Ci fixation in Roseiflexus spp. were labeled, establishing that members of this taxocene contribute to Ci fixation. Other taxa showed much lower [13C]bicarbonate incorporation.IMPORTANCE Yellowstone hot spring mats have been studied as natural models for understanding microbial community ecology and as modern analogs of stromatolites, the earliest community fossils on Earth. Stable-isotope probing of proteins (Pro-SIP) permitted short-term interrogation of the taxa that are involved in the important process of light-driven Ci fixation in this highly active community and will be useful in linking other metabolic processes to mat taxa. Here, evidence is presented that Roseiflexus spp., which use the 3-hydroxypropionate bi-cycle, are active in Ci fixation. Because this pathway imparts a lower degree of selection of isotopically heavy Ci than does the Calvin-Benson-Bassham cycle, the results suggest a mechanism to explain why the natural abundance of 13C in mat biomass is greater than expected if only the latter pathway were involved. Understanding how mat community members influence the 13C/12C ratios of mat biomass will help geochemists interpret the 13C/12C ratios of organic carbon in the fossil record.
Subject(s)
Carbon Compounds, Inorganic/metabolism , Chloroflexi/metabolism , Hot Springs/microbiology , Microbiota , Synechococcus/metabolismABSTRACT
Complex interactions between roots and soil provide the nutrients and physical support required for robust plant growth. Yet, visualizing the root-soil interface is challenged by soil's opaque scattering characteristics. Herein, we describe methods for using optical coherence tomography (OCT) to provide non-destructive 3D and cross-sectional root imaging not available with traditional bright-field microscopy. OCT is regularly used for bioimaging, especially in ophthalmology, where it can detect retinal abnormalities. Prior use of OCT in plant biology has focused on surface defects of above-ground tissues, predominantly in food crops. Our results show OCT is also viable for detailed, in situ study of living plant roots. Using OCT for direct observations of root growth in soil can help elucidate key interactions between root morphology and various components of the soil environment including soil structure, microbial communities, and nutrient patches. Better understanding of these interactions can guide efforts to improve plant nutrient acquisition from soil to increase agricultural efficiency as well as better understand drivers of plant growth in natural systems.
Subject(s)
Plant Development , Plant Roots , Tomography, Optical Coherence/instrumentation , Tomography, Optical Coherence/methods , Crops, Agricultural , Cross-Sectional Studies , Equipment Design , Models, Biological , Plant Roots/cytology , Plant Roots/growth & development , Soil , Time FactorsABSTRACT
Over the past decades, Western European hedgerows have been declining as a result of land use change. Disused infrastructure corridors such as railways and tramways can host a range of existing and returning semi-natural habitats, including extensive hedgerow networks. However, long term corridor abandonment can result in network deterioration to gappy hedgerows, lines of trees and eventually individual scrub features. The loss of hedgerows results in the loss of many ecosystem services, habitat for species and landscape connectivity. This highlights an increasing need to find innovative solutions to recognise and appropriately maintain these hedgerow networks. European Greenways typically 'upcycle' disused infrastructure transport corridors for multi-use, non-motorised recreational public infrastructure. The potential for European greenways to maintain and restore hedgerows is of interest as a novel planning mechanism for enhancing green infrastructure in general. The aim of this study is to inform Greenway design and management through the evaluation of hedgerow significance (historical, ecological and landscape), condition and composition within a rural European Greenway landscape context. 81 hedgerows were sampled along a 70â¯km proposed Greenway route traversing a range of extensive and intensive landscapes. Hedgerows were surveyed using a rapid field score sheet which enabled significance and condition scoring. A hedgerow typology was subsequently developed based on species composition assemblages. Hedgerows were found to be highly ecologically significant and species rich throughout the route. On-going land use intensification was evident as significant sections of the former railway corridor were subsumed into intensive agriculture and afforestation. Management recommendations need to be adapted to the particular hedgerow group and surrounding landscape context, and take into account the varied requirements of different taxonomic groups. The study findings show Greenways have the potential to act as multi-functional green infrastructure (accomplishing both ecological and recreational objectives) through informed design to reinforce their nature conservation role and recognising hedgerows as integral landscape feature of Greenway corridor, at local level and as part of a wider European network.