scholarly journals Effects of uniform-allocation constraints in networked common-pool resource extraction games

2021 ◽  
Author(s):  
Andrew Schauf ◽  
Poong Oh
Keyword(s):  
Self Regulation ◽  
Population Level ◽  
Resource Extraction ◽  
Resource Quality ◽  
Common Pool ◽  
Adaptive Allocation ◽  
Multiple Resources ◽  
Best Response ◽  
Affiliation Network

Abstract Communities that share common-pool resources (CPRs) often coordinate their actions to sustain resource quality more effectively than if they were regulated by some centralized authority. Networked models of CPR extraction suggest that the flexibility of individual agents to selectively allocate extraction effort among multiple resources plays an important role in maximizing their payoffs. However, empirical evidence suggests that real-world CPR appropriators may often de-emphasize issues of allocation, for example by responding to the degradation of a single resource by reducing extraction from multiple resources, rather than by reallocating extraction effort away from the degraded resource. Here, we study the population-level consequences that emerge when individuals are constrained to apply an equal amount of extraction effort to all CPRs that are available to them within an affiliation network linking agents to resources. In systems where all resources have the same capacity, this uniform-allocation constraint leads to reduced collective wealth compared to unconstrained best-response extraction, but it can produce more egalitarian wealth distributions. The differences are more pronounced in networks that have higher degree heterogeneity among resources. In the case that the capacity of each CPR is proportional to its number of appropriators, the uniform-allocation constraint can lead to more efficient collective extraction since it serves to distribute the burden of over-extraction more evenly among the network’s CPRs. Our results reinforce the importance of adaptive allocation in self-regulation for populations who share linearly degrading CPRs; although uniform-allocation extraction habits can help to sustain higher resource quality than does unconstrained extraction, in general this does not improve collective benefits for a population in the long term.

A Case of Duodenal Neuroendocrine Carcinoma Treated with Amrubicin as Second-line Chemotherapy

2015 ◽  
Vol 24 (3) ◽  
pp. 379-382
Author(s):  
Tadahisa Inoue ◽  
Hitoshi Sano ◽  
Takashi Mizushima ◽  
Hirotada Nishie ◽  
Hiroyasu Iwasaki ◽  
...  
Keyword(s):  
Neuroendocrine Carcinoma ◽  
Distant Metastases ◽  
Salvage Chemotherapy ◽  
Second Line ◽  
Effective Treatment Option ◽  
Second Line Chemotherapy ◽  
Best Response ◽  
Long Term Effect ◽  
Line Chemotherapy

We present the case of a Japanese man in his 60s with duodenal neuroendocrine carcinoma with distant metastases. Chemotherapy with irinotecan plus cisplatin was initiated as a first-line regimen. However, disease progression was observed after only two cycles. Therefore, amrubicin was administered as a second-line chemotherapy. The patient showed a long-term effect of amrubicin therapy, and the best response was a partial response after seven cycles. For duodenal neuroendocrine carcinoma, amrubicin therapy can be considered an effective treatment option as salvage chemotherapy.

scholarly journals Responses of Vertebrate Wildlife to Oil and Natural Gas Development: Patterns and Frontiers

2021 ◽  
Author(s):  
A. D. Chalfoun
Keyword(s):  
Natural Gas ◽  
Anthropogenic Activities ◽  
Spatial Scales ◽  
Habitat Type ◽  
Population Level ◽  
Low Frequencies ◽  
Natural Gas Development ◽  
The Usa ◽  
Oil And Natural Gas

Abstract Purpose of Review Anthropogenic activities can lead to the loss, fragmentation, and alteration of wildlife habitats. I reviewed the recent literature (2014–2019) focused on the responses of avian, mammalian, and herpetofaunal species to oil and natural gas development, a widespread and still-expanding land use worldwide. My primary goals were to identify any generalities in species’ responses to development and summarize remaining gaps in knowledge. To do so, I evaluated the directionality of a wide variety of responses in relation to taxon, location, development type, development metric, habitat type, and spatiotemporal aspects. Recent Findings Studies (n = 70) were restricted to the USA and Canada, and taxonomically biased towards birds and mammals. Longer studies, but not those incorporating multiple spatial scales, were more likely to detect significant responses. Negative responses of all types were present in relatively low frequencies across all taxa, locations, development types, and development metrics but were context-dependent. The directionality of responses by the same species often varied across studies or development metrics. Summary The state of knowledge about wildlife responses to oil and natural gas development has developed considerably, though many biases and gaps remain. Studies outside of North America and that focus on herpetofauna are lacking. Tests of mechanistic hypotheses for effects, long-term studies, assessment of response thresholds, and experimental designs that isolate the effects of different stimuli associated with development, remain critical. Moreover, tests of the efficacy of habitat mitigation efforts have been rare. Finally, investigations of the demographic effects of development across the full annual cycle were absent for non-game species and are critical for the estimation of population-level effects.

scholarly journals Evidence-Based Digital Tools for Weight Loss Maintenance: The NoHoW Project

Obesity Facts ◽  
2021 ◽  
pp. 1-14
Author(s):  
R. James Stubbs ◽  
Cristiana Duarte ◽  
António L. Palmeira ◽  
Falko F. Sniehotta ◽  
Graham Horgan ◽  
...  
Keyword(s):  
Weight Loss ◽  
Behaviour Change ◽  
Digital Health ◽  
Self Regulation ◽  
Self Management ◽  
Behaviour Change Techniques ◽  
Evidence Based ◽  
Behavioural Science ◽  
Digital Architecture

<b><i>Background:</i></b> Effective interventions and commercial programmes for weight loss (WL) are widely available, but most people regain weight. Few effective WL maintenance (WLM) solutions exist. The most promising evidence-based behaviour change techniques for WLM are self-monitoring, goal setting, action planning and control, building self-efficacy, and techniques that promote autonomous motivation (e.g., provide choice). Stress management and emotion regulation techniques show potential for prevention of relapse and weight regain. Digital technologies (including networked-wireless tracking technologies, online tools and smartphone apps, multimedia resources, and internet-based support) offer attractive tools for teaching and supporting long-term behaviour change techniques. However, many digital offerings for weight management tend not to include evidence-based content and the evidence base is still limited. <b><i>The Project:</i></b> First, the project examined why, when, and how many European citizens make WL and WLM attempts and how successful they are. Second, the project employed the most up-to-date behavioural science research to develop a digital toolkit for WLM based on 2 key conditions, i.e., self-management (self-regulation and motivation) of behaviour and self-management of emotional responses for WLM. Then, the NoHoW trial tested the efficacy of this digital toolkit in adults who achieved clinically significant (≥5%) WL in the previous 12 months (initial BMI ≥25). The primary outcome was change in weight (kg) at 12 months from baseline. Secondary outcomes included biological, psychological, and behavioural moderators and mediators of long-term energy balance (EB) behaviours, and user experience, acceptability, and cost-effectiveness. <b><i>Impact:</i></b> The project will directly feed results from studies on European consumer behaviour, design and evaluation of digital toolkits self-management of EB behaviours into development of new products and services for WLM and digital health. The project has developed a framework and digital architecture for interventions in the context of EB tracking and will generate results that will help inform the next generation of personalised interventions for effective self-management of weight and health.

scholarly journals Advancement in long-distance bird migration through individual plasticity in departure

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Jesse R. Conklin ◽  
Simeon Lisovski ◽  
Phil F. Battley
Keyword(s):  
Bird Migration ◽  
Population Level ◽  
Breeding Site ◽  
Environmental Constraints ◽  
Adaptive Responses ◽  
Long Distance ◽  
Direct Observations ◽  
Breeding Resources ◽  
Plastic Responses

AbstractGlobally, bird migration is occurring earlier in the year, consistent with climate-related changes in breeding resources. Although often attributed to phenotypic plasticity, there is no clear demonstration of long-term population advancement in avian migration through individual plasticity. Using direct observations of bar-tailed godwits (Limosa lapponica) departing New Zealand on a 16,000-km journey to Alaska, we show that migration advanced by six days during 2008–2020, and that within-individual advancement was sufficient to explain this population-level change. However, in individuals tracked for the entire migration (50 total tracks of 36 individuals), earlier departure did not lead to earlier arrival or breeding in Alaska, due to prolonged stopovers in Asia. Moreover, changes in breeding-site phenology varied across Alaska, but were not reflected in within-population differences in advancement of migratory departure. We demonstrate that plastic responses can drive population-level changes in timing of long-distance migration, but also that behavioral and environmental constraints en route may yet limit adaptive responses to global change.

Do researchers impact their study populations? Assessing the effect of field procedures in a long term population monitoring of sea kraits

2012 ◽  
Vol 33 (3-4) ◽  
pp. 365-372 ◽  
Author(s):  
Thomas Fauvel ◽  
François Brischoux ◽  
Marine Jeanne Briand ◽  
Xavier Bonnet
Keyword(s):  
Body Condition ◽  
New Caledonia ◽  
Stress Hormones ◽  
Population Level ◽  
Population Monitoring ◽  
Long Term Effects ◽  
Negative Effects ◽  
Short Term ◽  
Head Morphology

Long term population monitoring is essential to ecological studies; however, field procedures may disturb individuals. Assessing this topic is important in worldwide declining taxa such as reptiles. Previous studies focussed on animal welfare issues and examined short-term effects (e.g. increase of stress hormones due to handling). Long-term effects with possible consequences at the population level remain poorly investigated. In the present study, we evaluated the effects of widely used field procedures (e.g. handling, marking, forced regurgitation) both on short-term (hormonal stress response) and on long-term (changes in body condition, survival) scales in two intensively monitored populations of sea kraits (Laticauda spp.) in New Caledonia. Focusing on the most intensively monitored sites, from 2002 to 2012, we gathered approximately 11 200 captures/recaptures on 4500 individuals. Each snake was individually marked (scale clipping + branding) and subjected to various measurements (e.g. body size, head morphology, palpation). In addition, a subsample of more than 500 snakes was forced to regurgitate their prey for dietary analyses. Handling caused a significant stress hormonal response, however we found no detrimental long-term effect on body condition. Forced regurgitation did not cause any significant effect on both body condition one year later and survival. These results suggest that the strong short-term stress provoked by field procedures did not translate into negative effects on the population. Although similar analyses are required to test the validity of our conclusions in other species, our results suggest distinguishing welfare and population issues to evaluate the potential impact of population surveys.

scholarly journals Decline in the frequency and benefits of multiple brooding in great tits as a consequence of a changing environment

2009 ◽  
Vol 276 (1663) ◽  
pp. 1845-1854 ◽  
Author(s):  
Arild Husby ◽  
Loeske E.B. Kruuk ◽  
Marcel E. Visser
Keyword(s):  
Life History Traits ◽  
Parus Major ◽  
Population Level ◽  
Climatic Conditions ◽  
Long Term Study ◽  
Double Brooding ◽  
First Clutch ◽  
Second Clutch ◽  
Reproductive Events

For multiple-brooded species, the number of reproductive events per year is a major determinant of an individual's fitness. Where multiple brooding is facultative, its occurrence is likely to change with environmental conditions, and, as a consequence, the current rates of environmental change could have substantial impacts on breeding patterns. Here we examine temporal population-level trends in the proportion of female great tits ( Parus major ) producing two clutches per year (‘double brooding’) in four long-term study populations in The Netherlands, and show that the proportion of females that double brood has declined in all populations, with the strongest decline taking place in the last 30 years of the study. For one of the populations, for which we have data on caterpillar abundance, we show that the probability that a female produces a second clutch was related to the timing of her first clutch relative to the peak in caterpillar abundance, and that the probability of double brooding declined over the study period. We further show that the number of recruits from the second clutch decreased significantly over the period 1973–2004 in all populations. Our results indicate that adjustment to changing climatic conditions may involve shifts in life-history traits other than simply the timing of breeding.

scholarly journals Predictors of invertebrate biomass and rate of advancement of invertebrate phenology across eight sites in the North American Arctic

Polar Biology ◽  
2021 ◽  
Vol 44 (2) ◽  
pp. 237-257
Author(s):  
Rebecca Shaftel ◽  
Daniel J. Rinella ◽  
Eunbi Kwon ◽  
Stephen C. Brown ◽  
H. River Gates ◽  
...  
Keyword(s):  
Prey Availability ◽  
Population Level ◽  
The Arctic ◽  
Environmental Drivers ◽  
Chick Survival ◽  
The North ◽  
Phenological Mismatch ◽  
Nesting Sites ◽  
North American Arctic

AbstractAverage annual temperatures in the Arctic increased by 2–3 °C during the second half of the twentieth century. Because shorebirds initiate northward migration to Arctic nesting sites based on cues at distant wintering grounds, climate-driven changes in the phenology of Arctic invertebrates may lead to a mismatch between the nutritional demands of shorebirds and the invertebrate prey essential for egg formation and subsequent chick survival. To explore the environmental drivers affecting invertebrate availability, we modeled the biomass of invertebrates captured in modified Malaise-pitfall traps over three summers at eight Arctic Shorebird Demographics Network sites as a function of accumulated degree-days and other weather variables. To assess climate-driven changes in invertebrate phenology, we used data from the nearest long-term weather stations to hindcast invertebrate availability over 63 summers, 1950–2012. Our results confirmed the importance of both accumulated and daily temperatures as predictors of invertebrate availability while also showing that wind speed negatively affected invertebrate availability at the majority of sites. Additionally, our results suggest that seasonal prey availability for Arctic shorebirds is occurring earlier and that the potential for trophic mismatch is greatest at the northernmost sites, where hindcast invertebrate phenology advanced by approximately 1–2.5 days per decade. Phenological mismatch could have long-term population-level effects on shorebird species that are unable to adjust their breeding schedules to the increasingly earlier invertebrate phenologies.

Overall survival benefit from tebentafusp in patients with best response of progressive disease.

2021 ◽  
Vol 39 (15_suppl) ◽  
pp. 9509-9509
Author(s):  
Anthony M. Joshua ◽  
Jean-Francois Baurain ◽  
Sophie Piperno-Neumann ◽  
Paul Nathan ◽  
Jessica Cecile Hassel ◽  
...  
Keyword(s):  
Overall Survival ◽  
Safety Profile ◽  
Progressive Disease ◽  
Analysis Data ◽  
Cell Receptor ◽  
Kaplan Meier ◽  
Immortal Time Bias ◽  
Best Response ◽  
Overall Survival Benefit

9509 Background: Tebentafusp (tebe) is the first T cell receptor (TCR) therapeutic to demonstrate an overall survival (OS) benefit in a randomized Phase 3 (Ph3) study [ NCT03070392 ]. In Ph2, 42% of pts with best overall response (BOR) of progressive disease (PD) survived > 1 year (yr), suggesting RECIST-based radiographic assessments underestimate OS benefit of tebe. Here we analyzed OS in the Ph3 study in a cohort of pts with BOR of PD by comparing tebe to the control arm of investigator’s choice (IC). Methods: 378 pts were randomized in a 2:1 ratio to tebe vs. IC. BOR was assessed by investigators using RECIST v1.1. Treatment beyond first disease progression (TBP) was permitted for both arms. On the IC arm, only patients receiving pembrolizumab (pembro) continued with TBP and were included in the TBP-related analyses. No crossover to tebe was permitted; investigators were free to choose subsequent therapy. This analysis was conducted on the first interim analysis (data extracted Nov-2020). Kaplan-Meier estimates of OS were based on Day 100 landmark to eliminate immortal time bias and to capture majority of the PDs. Results: By Day 100, PD as BOR occurred in 52% (130/252) of tebe pts (PD-tebe) vs. 60% (76/126) of IC pts (PD-IC). Key baseline characteristics including lactate dehydrogenase, alkaline phosphatase, ECOG performance, age, and sex were similar between PD-tebe vs PD-IC. The proportion of pts with PD due to progression of target lesions (TL), non-TL, or new lesions were also similar between the two groups. More pts received TBP among PD-tebe 53% (69/130) vs PD-pembro 16% (10/61). Median duration of TBP was longer for PD-tebe (7 weeks) vs PD-Pembro (3 weeks). The safety profile of PD-tebe pts during TBP was similar to all tebe-treated pts. OS was superior for PD-tebe vs PD-IC, HR = 0.41 (95%CI 0.25-0.66), even when considering key baseline covariates. While some pts had regression of TL despite diagnosis of PD ( < 10% of pts), the OS benefit remained even when limited to pts with best change of tumor growth of TL, HR 0.46 (0.29, 0.73). 58% (75/130) PD-tebe and 52% (40/76) PD-IC pts received subsequent therapies. In a landmark OS analysis of these pts beginning on 1st day of subsequent therapy, prior tebe was associated with better OS vs. prior IC, HR 0.59 (95%CI 0.36-0.96). Conclusions: Tebe is the first TCR therapeutic to demonstrate an OS benefit in a solid tumor. Surprisingly, a strong OS benefit from tebe is observed even in pts with BOR of PD, suggesting that RECIST-based radiographic assessments do not capture the complete benefit from tebe. The safety profile of tebe during TBP was consistent with that for long-term tebe treatment. Clinical trial information: NCT03070392.

scholarly journals Temporal Evolution of Immunity Distributions in a Population with Waning and Boosting

Complexity ◽  
2018 ◽  
Vol 2018 ◽  
pp. 1-13
Author(s):  
M. V. Barbarossa ◽  
M. Polner ◽  
G. Röst
Keyword(s):  
Mathematical Model ◽  
Steady State ◽  
Temporal Evolution ◽  
Disease Outbreaks ◽  
Population Level ◽  
Coupled System ◽  
Disease Outbreak ◽  
Periodic Disease ◽  
Evolution Of Immunity

We investigate the temporal evolution of the distribution of immunities in a population, which is determined by various epidemiological, immunological, and demographical phenomena: after a disease outbreak, recovered individuals constitute a large immune population; however, their immunity is waning in the long term and they may become susceptible again. Meanwhile, their immunity can be boosted by repeated exposure to the pathogen, which is linked to the density of infected individuals present in the population. This prolongs the length of their immunity. We consider a mathematical model formulated as a coupled system of ordinary and partial differential equations that connects all these processes and systematically compare a number of boosting assumptions proposed in the literature, showing that different boosting mechanisms lead to very different stationary distributions of the immunity at the endemic steady state. In the situation of periodic disease outbreaks, the waveforms of immunity distributions are studied and visualized. Our results show that there is a possibility to infer the boosting mechanism from the population level immune dynamics.

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