Relationships between size, biomass allocation, reproduction, and survival in Triglochin palustris: implications for the effects of goose herbivory

1998 ◽  
Vol 76 (12) ◽  
pp. 2164-2176 ◽  
Author(s):  
Christa PH Mulder ◽  
R W Ruess
Keyword(s):  
Biomass Allocation ◽  
Vegetative Reproduction ◽  
Population Level ◽  
Plant Size ◽  
Flowering Plants ◽  
Parent Plant ◽  
Trade Off ◽  
Plant Parts ◽  
Vegetative Plant ◽  
Increased Risk

Triglochin palustris (arrowgrass) on the Yukon-Kuskokwim Delta reproduces primarily vegetatively, and is heavily grazed by geese. To link effects of herbivory on individuals to population-level effects, we examined relationships between plant size or biomass allocation and survival or reproduction by matching more than 400 individuals into groups and sequentially harvesting individuals from each group. We compared size and biomass allocation for nonreproductive plants and plants with either or both modes of reproduction in exclosed plots, and examined effects of clipping leaves or inflorescences in flowering and nonflowering plants. Survival and vegetative reproduction increased with plant size, particularly bulb size, but was unrelated to biomass allocation. Very small plants do not reproduce, very large plants produce both flowers and stolons, and intermediate sized plants produce either flowers or stolons. Inflorescences require greater biomass investment than stolons, resulting in decreased allocation to all vegetative plant parts except roots. Plants that produce flowers seldom regenerate overwintering bulbs on the parent plant, indicating a trade-off with survival. Geese may decrease flowering by reducing plant size and consuming inflorescences. Flowering plants have much higher rates of herbivory than other plants, suggesting that increased risk of herbivory results in low rates of flowering.Key words: Alaska, brant geese, sexual reproduction, subarctic salt marsh, vegetative reproduction.

Gendered experiences of unemployment, suicide and self-harm: a population-level record linkage study

2021 ◽  
pp. 1-9
Author(s):  
R. Cunningham ◽  
A. Milner ◽  
S. Gibb ◽  
V. Rijnberg ◽  
G. Disney ◽  
...  
Keyword(s):  
Mental Health ◽  
Employment Status ◽  
Mental Health Problems ◽  
Labour Force ◽  
Antidepressant Medication ◽  
Population Level ◽  
Related Factors ◽  
Data Infrastructure ◽  
Increased Risk ◽  
Self Harm

Abstract Background Unemployment and being not in the labour force (NILF) are risk factors for suicide, but their association with self-harm is unclear, and there is continuing debate about the role of confounding by prior mental health conditions. We examine associations between employment status and self-harm and suicide in a prospective cohort, taking into account prior mental-health-related factors. Methods We used linked data from the New Zealand Integrated Data Infrastructure. The outcomes were chosen to be hospital presentation for self-harm and death by suicide. The exposure was employment status, defined as employed, unemployed, or NILF, measured at the 2013 Census. Confounders included demographic factors and mental health history (use of antidepressant medication, use of mental health services, and prior self-harm). Logistic regression was used to model effects. Analyses were stratified by gender. Results For males, unemployment was associated with an increased risk of suicide [odds ratio (OR): 1.48, 95% confidence interval (CI): 1.20–1.84] and self-harm (OR: 1.55, 95% CI: 1.45–1.68) after full adjustment for confounders. NILF was associated with an increased risk of self-harm (OR: 1.43, 95% CI: 1.32–1.55), but less of an association was seen with suicide (OR: 1.19, 95% CI: 0.94–1.49). For females, unemployment was associated with an increased risk of suicide (OR: 1.30, 95% CI: 0.93–1.80) and of self-harm (OR: 1.52, 95% CI: 1.43–1.62), and NILF was associated with a similar increase in risk for suicide (OR: 1.31, 95% CI: 0.98–1.75) and self-harm (OR: 1.32, 95% CI: 1.26–1.40). Discussion Exclusion from employment is associated with a considerably heightened risk of suicide and self-harm for both men and women, even among those without prior mental health problems.

Dispersal of Goeppertia marantifolia clonal offspring increases with greater canopy openness and larger plant size

2017 ◽  
Vol 33 (2) ◽  
pp. 107-113 ◽  
Author(s):  
David P. Matlaga ◽  
Rachel K. Snyder ◽  
Carol C. Horvitz
Keyword(s):  
Leaf Area ◽  
Light Availability ◽  
Plant Size ◽  
Dispersal Distance ◽  
Permanent Plots ◽  
Canopy Openness ◽  
Parent Plant ◽  
Analysis Model ◽  
Corcovado National Park ◽  
Positive Effect

Abstract:Many plants within the neotropical understorey produce both seeds and clonal offspring. Plant attributes (i.e. size) and variability in light can influence seed dispersal but it is not known if these factors influence the dispersal of clonal offspring. Our goal was to determine if canopy openness and plant size influence clonal-offspring dispersal of the herb Goeppertia marantifolia, which produces clonal bulbils on above-ground shoots. We monitored plants in permanent plots with varying levels of canopy openness in Corcovado National Park, Costa Rica. We recorded canopy openness, leaf area and the distance clonal offspring travelled from their parent plant (N = 283). Our path analysis model demonstrated that canopy openness had a strong positive effect on dispersal distance, while the association between clonal-offspring dispersal distance and parent plant leaf area was only weakly positive. On average, plants experiencing high canopy openness dispersed their clonal offspring further than plants under low canopy openness (124 cm vs. 79 cm, respectively). Contrary to studies on species that utilize rhizomes and stolons for clonal reproduction, we found that in this bulbil-producing species light availability is positively associated with clonal dispersal distance. Therefore, the influence of resource availability on spatial population dynamics of clonal species may be influenced by the species’ growth-form.

Abstract P541: Avoiding the Radial Paradox: Radial Adoption is Not Associated With Worse Femoral Outcomes in Neuroendovascular Cases

Stroke ◽  
2021 ◽  
Vol 52 (Suppl_1) ◽  
Author(s):  
D. Andrew Wilkinson ◽  
Neil Majmundar ◽  
Joshua Catapano ◽  
Tyler Cole ◽  
Jacob Baranoski ◽  
...  
Keyword(s):  
Multivariate Analysis ◽  
Vascular Access ◽  
Older Patients ◽  
Population Level ◽  
Single Center ◽  
Access Site ◽  
Patient Level ◽  
Transradial Access ◽  
Increased Risk ◽  
Historical Controls

Background and Purpose: Transradial access (TRA) for neuroendovascular procedures is increasing in prevalence, although numerous procedures are still performed using transfemoral access (TFA). Some cardiology studies have suggested the safety benefits of TRA at a patient level may be offset at a population level by a paradoxical increase in TFA vascular access site complications (VASCs) associated with radial adoption, the so-called “radial paradox.” We studied the effect of TRA adoption on TFA performance and VASC rates in neuroendovascular procedures. Methods: Data were collected for all neuroendovascular procedures performed over a 10-month period by trainees after implementation of a radial-first paradigm at a single center. Results: Over the study period, 1,084 procedures were performed, including 689 (63.6%) via TRA and 395 (36.4%) via TFA. In comparison to TRA, TFA cases were performed in older patients (TFA 63 ±15 vs. TRA 56 ±16), were predominantly male (TFA 52.9% vs. TRA 38.6%), used larger sheath sizes (≥7 French, TFA 56.6% vs. TRA 2.3%), were more often emergent (TFA 37.7% vs. TRA 1.1%), and used tPA administration (TFA 15.3% vs. TRA 0%) (p<.001 for all comparisons). Overall, 29 VASCs occurred (2.7%), including 27 minor (TFA 4.6% [18/395] vs. TRA 1.3% [9/689], p=.002) and 2 major (TFA 0.3% [1/395] vs. TRA 0.1% [1/689], p>.99) complications. After multivariate analysis, independent predictors of any VASC included TFA (OR 2.8, 95% CI 1.1-7.4) and use of dual antiplatelets (OR 4.2, 95% CI 1.6—11.1). Conclusions: TFA remains an essential route for neuroendovascular procedures, accounting for 36.4% of cases under a radial-first paradigm. TFA is disproportionately performed in patients undergoing procedures with an increased-risk for VASCs, though the minor and major VASC rates are comparable to historical controls. TFA proficiency may still be achieved in radial-first training without an increase in femoral complications.

scholarly journals Electroencephalographic Evidence for Individual Neural Inertia in Mice That Decreases With Time

2022 ◽  
Vol 15 ◽  
Author(s):  
Andrzej Z. Wasilczuk ◽  
Qing Cheng Meng ◽  
Andrew R. McKinstry-Wu
Keyword(s):  
Stochastic Model ◽  
Path Dependence ◽  
Inbred Mice ◽  
Population Level ◽  
Supervised Machine Learning ◽  
State Transitions ◽  
Intrinsic Resistance ◽  
Linear Discriminant ◽  
Individual Level ◽  
Increased Risk

Previous studies have demonstrated that the brain has an intrinsic resistance to changes in arousal state. This resistance is most easily measured at the population level in the setting of general anesthesia and has been termed neural inertia. To date, no study has attempted to determine neural inertia in individuals. We hypothesize that individuals with markedly increased or decreased neural inertia might be at increased risk for complications related to state transitions, from awareness under anesthesia, to delayed emergence or confusion/impairment after emergence. Hence, an improved theoretical and practical understanding of neural inertia may have the potential to identify individuals at increased risk for these complications. This study was designed to explicitly measure neural inertia in individuals and empirically test the stochastic model of neural inertia using spectral analysis of the murine EEG. EEG was measured after induction of and emergence from isoflurane administered near the EC50 dose for loss of righting in genetically inbred mice on a timescale that minimizes pharmacokinetic confounds. Neural inertia was assessed by employing classifiers constructed using linear discriminant or supervised machine learning methods to determine if features of EEG spectra reliably demonstrate path dependence at steady-state anesthesia. We also report the existence of neural inertia at the individual level, as well as the population level, and that neural inertia decreases over time, providing direct empirical evidence supporting the predictions of the stochastic model of neural inertia.

scholarly journals PHYTOREMEDIATION OF HEAVY METALS BY THE DOMINANT MANGROVE ASSOCIATE SPECIES OF INDIAN SUNDARBANS

2021 ◽  
Vol 29 (4) ◽  
pp. 391-402
Author(s):  
Pritam Mukherjee ◽  
Prosenjit Pramanick ◽  
Sufia Zaman ◽  
Abhijit Mitra
Keyword(s):  
Heavy Metals ◽  
Organ Specificity ◽  
Salicornia Brachiata ◽  
Plant Parts ◽  
Vegetative Plant ◽  
Suaeda Maritima ◽  
Indian Sundarbans ◽  
Stems And Leaves ◽  
Associate Species ◽  
Mangrove Associate

The present study aims to investigate the phytoremediation potential of zinc (Zn), copper (Cu), and lead (Pb) by two dominant mangrove associate species, Suaeda maritima, and Salicornia brachiata, found in the high saline supralittoral zone of Indian Sundarbans in four stations of the Hooghly-Matla estuarine complex during the premonsoon season (May 2019). We found that concentrations of biologically available heavy metals (HMs) in the ambient soil and bioaccumulated HMs within the vegetative plant parts occurred as per the order: Sagar South > Bakkhali > Jharkhali > Bali Island. The order of biologically available and bioaccumulated HMs was Zn > Cu > Pb. Interestingly, the selected HMs display high organ-specificity for both species with the highest enrichment in roots, followed by stems and leaves. We propose that these halophytes could be used as agents of phytoremediation and their farming would be effective in the ecorestoration of this deltaic complex in context to conservative pollutants.

Guidance for Using State-and Prediction-Based Theory

2020 ◽  
pp. 93-122
Keyword(s):  
Population Level ◽  
Population Models ◽  
Dynamic State ◽  
Trade Off ◽  
State Variable

This chapter outlines the guidance on using state- and prediction-based theory (SPT) to build models of populations and communities of adaptive individuals, detailing five steps unique to SPT. The most important aspect of SPT to remember is that one is not trying to build optimal, or even necessarily accurate, models of how an organism's behavior affects its future fitness. Instead, one is trying to find simplistic models that produce realistic behavior in contexts where optimization is impossible. While SPT can be used like dynamic state variable modeling (DSVM), as a framework for thinking about and modeling how an individual makes a particular decision, its main purpose is to model adaptive trade-off decisions in individual-based population models. Thus, using SPT is part of the larger process of developing, analyzing, and applying an IBM to address population-level questions, and the five steps therefore include that process.

Epilepsy in adulthood: Prevalence, incidence, and associated antiepileptic drug use in autistic adults in a state Medicaid system

Autism ◽  
2020 ◽  
pp. 136236132094298
Author(s):  
Lauren Bishop ◽  
Kiley J McLean ◽  
Eric Rubenstein
Keyword(s):  
Intellectual Disability ◽  
Drug Use ◽  
Confidence Interval ◽  
Antiepileptic Drug ◽  
Population Level ◽  
Autistic People ◽  
Increased Risk ◽  
Autistic Adults ◽  
Antiepileptic Medications ◽  
Incident Cases

Although epilepsy commonly presents with autism in children, it is currently unknown whether established estimates represent the prevalence and incidence of epilepsy in autistic adults. Our objective was to use population-level Medicaid data to determine prevalence, incidence, and antiepileptic drug use associated with epilepsy in a unique population of autistic adults aged 21+ with (N = 2738) and without (N = 4775) intellectual disability and to compare results to adults with intellectual disability alone (N = 18,429). We found that 34.6% of autistic adults with intellectual disability and 11.1% of autistic adults without intellectual disability had epilepsy, compared to 27.0% of adults with intellectual disability alone. New incidence of epilepsy was 23.6 incident cases per 1000 person years (95% confidence interval: 21.3, 26.2) in autistic adults with intellectual disability, 7.7 incident cases per 1000 person years (95% confidence interval: 6.6, 8.9) in autistic adults without intellectual disability, and 15.9 incident cases per 1000 person years (95% confidence interval: 15.2, 16.7) in adults with intellectual disability alone. Female sex and intellectual disability were associated with increased risk of prevalent and incident epilepsy in autistic adults. Findings underscore the importance of treating prevalent epilepsy and screening and preventing incident epilepsy in autistic adults as they age. Lay abstract Epilepsy is more common in autistic children compared to children without autism, but we do not have good estimates of how many autistic adults have epilepsy. We used data from a full population of 7513 autistic adults who received Medicaid in Wisconsin to figure out the proportion of autistic adults who have epilepsy, as compared to 18,429 adults with intellectual disability. We also wanted to assess how often epilepsy is first diagnosed in adulthood. Finally, we wanted to see whether antiepileptic drugs are being used to treat epilepsy in autistic adults. We found that 34.6% of autistic adults with intellectual disability and 11.1% of autistic adults without intellectual disability had epilepsy, compared to 27.0% of adults with intellectual disability alone. Autistic women and autistic adults with intellectual disability were more likely than autistic men and autistic adults without intellectual disability to have both previous and new diagnoses of epilepsy. Finally, we found that antiepileptic medications are commonly prescribed to autistic people who do not have epilepsy potentially to treat mental health conditions or behavior problems, and that antiepileptic medications are not always prescribed to autistic people with epilepsy even though they are indicated as a first-line epilepsy treatment. The findings of this study highlight the need to effectively treat and prevent epilepsy in autistic adults.

scholarly journals StudiCare mindfulness—study protocol of a randomized controlled trial evaluating an internet- and mobile-based intervention for college students with no and “on demand” guidance

Trials ◽  
2020 ◽  
Vol 21 (1) ◽  
Author(s):  
Ann-Marie Küchler ◽  
Dana Schultchen ◽  
Olga Pollatos ◽  
Morten Moshagen ◽  
David D. Ebert ◽  
...  
Keyword(s):  
Mental Health ◽  
College Students ◽  
Randomized Controlled Trial ◽  
Controlled Trial ◽  
Population Level ◽  
Control Group ◽  
Cognitive Fusion ◽  
On Demand ◽  
Randomized Controlled ◽  
Increased Risk

Abstract Background College is an exciting but also challenging time with an increased risk for mental health issues. Only a minority of the college students concerned get professional help, a problem that might be improvable by internet- and mobile-based interventions (IMIs). However, adherence of IMIs is a concern. While guidance might be a solution, it is resource-intensive, derailing potential implementation on population level. The first aim of this trial is to evaluate the efficacy of the IMI StudiCare Mindfulness (StudiCare-M) for college students with “on demand” and no guidance. The second aim is to examine potential moderators and mediators, contributing to the questions of “how” and “for whom” such interventions work. Methods In this three-armed randomized controlled trial, both an unguided and “guidance on demand” (GoD) condition of StudiCare-M are compared to a waitlist control group. StudiCare-M is based on principles of acceptance and commitment therapy and stress management and consists of 7 modules plus two booster sessions. Participants in the GoD condition may ask their e-coach for support whenever needed. A total of 387 college students with moderate to low mindfulness are recruited at 15+ cooperating universities in Germany, Austria, and Switzerland via circular emails. Assessments take place before as well as 1, 2, and 6 months after randomization. The primary outcome is mindfulness. Secondary outcomes include stress, depression, anxiety, interoception, presenteeism, wellbeing, intervention satisfaction, adherence, and potential side effects. Among examined moderators and mediators are sociodemographic variables, pre-treatment symptomatology, treatment expectancy, self-efficacy, cognitive fusion, emotion regulation, and alexithymia. All data will be analyzed according to intention-to-treat (ITT) principles. Discussion Providing effective interventions to help college students become more resilient can make a valuable contribution to the health and functionality of future society. If effective under the condition of minimal or no guidance, StudiCare-M offers a low-threshold potentially resource-efficient possibility to enhance college student mental health on a population level. Moderation- and mediation analyses will deliver further insights for optimization of target groups and intervention content. Trial registration WHO International Clinical Trials Registry Platform via the German Clinical Studies Trial Register DRKS00014774. Registered on 18 May 2018.

scholarly journals Human Papillomavirus Genotype Replacement: Still Too Early to Tell?

2020 ◽  
Author(s):  
Irene Man ◽  
Simopekka Vänskä ◽  
Matti Lehtinen ◽  
Johannes A Bogaards
Keyword(s):  
Human Papillomavirus ◽  
Hpv Vaccination ◽  
Population Level ◽  
Cross Protection ◽  
Transmission Model ◽  
Trade Off ◽  
Long Run ◽  
Vaccine Type ◽  
Cross Immunity ◽  
Different Levels

Abstract Background Although human papillomavirus (HPV) vaccines are highly efficacious in protecting against HPV infections and related diseases, vaccination may trigger replacement by nontargeted genotypes if these compete with the vaccine-targeted types. HPV genotype replacement has been deemed unlikely, based on the lack of systematic increases in the prevalence of nonvaccine-type (NVT) infection in the first decade after vaccination, and on the presence of cross-protection for some NVTs. Methods To investigate whether type replacement can be inferred from early postvaccination surveillance, we constructed a transmission model in which a vaccine type and an NVT compete through infection-induced cross-immunity. We simulated scenarios of different levels of cross-immunity and vaccine-induced cross-protection to the NVT. We validated whether commonly used measures correctly indicate type replacement in the long run. Results Type replacement is a trade-off between cross-immunity and cross-protection; cross-immunity leads to type replacement unless cross-protection is strong enough. With weak cross-protection, NVT prevalence may initially decrease before rebounding into type replacement, exhibiting a honeymoon period. Importantly, vaccine effectiveness for NVTs is inadequate for indicating type replacement. Conclusions Although postvaccination surveillance thus far is reassuring, it is still too early to preclude type replacement. Monitoring of NVTs remains pivotal in gauging population-level impacts of HPV vaccination.

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