Avoiding or restricting defectors in public goods games?

When creating a public good, strategies or mechanisms are required to handle defectors. We first show mathematically and numerically that prior agreements with posterior compensations provide a strategic solution that leads to substantial levels of cooperation in the context of public goods games, results that are corroborated by available experimental data. Notwithstanding this success, one cannot, as with other approaches, fully exclude the presence of defectors, raising the question of how they can be dealt with to avoid the demise of the common good. We show that both avoiding creation of the common good, whenever full agreement is not reached, and limiting the benefit that disagreeing defectors can acquire, using costly restriction mechanisms, are relevant choices. Nonetheless, restriction mechanisms are found the more favourable, especially in larger group interactions. Given decreasing restriction costs, introducing restraining measures to cope with public goods free-riding issues is the ultimate advantageous solution for all participants, rather than avoiding its creation.SCOPUS: ar.jinfo:eu-repo/semantics/publishe

Charcoal chronology of the Amazon forest: A record of biodiversity preserved by ancient fires

This is the author accepted manuscript. The final version is available from Elsevier via the DOI in this record.he Amazon region holds a wide variety of ethnic groups and microclimates, enabling different interactions between humans and environment. To better understand the evolution of this region, ancient remains need to be analysed by all possible means. In this context, the study of natural and/or anthropogenic fires through the analysis of carbonized remains can give information on past climate, species diversity, and human intervention in forests and landscapes. In the present work, we undertook an anthracological analysis along with the 14 C dating of charcoal fragments using accelerator mass spectrometry (AMS). Charcoal samples from forest soils collected from seven different locations in the Amazon Basin were taxonomically classified and dated. Out of the 16 groups of charcoal fragments identified, five contained more than one taxonomic type, with the Fabaceae, Combretaceae and Sapotaceae families having the highest frequencies. 14 C charcoal dates span ∼6000 years (from 6876 to 365 yr BP) among different families, with the most significant variation observed for two fragments from the same sampling location (spanning 4000 14 C yr). Some sample sets resulted in up to five different families. These findings demonstrate the importance of the association between anthracological identification and radiocarbon dating in the reconstruction of paleo-forest composition and fire history.The authors thank the Brazilian agencies Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq), Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES), and Fundação Carlos Chagas Filho de Amparo à Pesquisa do Estado do Rio de Janeiro (FAPERJ). KDM thanks CNPq for fellowship 305079/2014–0. CL thanks FAPEAM/FAPESP (09/53369-6, led by Flávia Regina Capellotto Costa) for financial support and Thaise Emílio, José Luiz Purri da Veiga Pinto, Rosineide Machado and Francislaide da Silva Costa for help with charcoal collection. TRF, BSM, and BHM acknowledge financial support from NERC (NE/N011570/1), CAPES/CNPq Science without Borders (PVE 177/2012 and PVE 401279/2014-6), CNPq/PPBio (457602/2012-0), CNPq/PELD (403725/2012-7) and the University of Exeter - College of Life and Environmental Sciences

Patient-Specific Prosthetic Fingers by Remote Collaboration - A Case Study

The concealment of amputation through prosthesis usage can shield an amputee from social stigma and help improve the emotional healing process especially at the early stages of hand or finger loss. However, the traditional techniques in prosthesis fabrication defy this as the patients need numerous visits to the clinics for measurements, fitting and follow-ups. This paper presents a method for constructing a prosthetic finger through online collaboration with the designer. The main input from the amputee comes from the Computer Tomography (CT) data in the region of the affected and the non-affected fingers. These data are sent over the internet and the prosthesis is constructed using visualization, computer-aided design and manufacturing tools. The finished product is then shipped to the patient. A case study with a single patient having an amputated ring finger at the proximal interphalangeal joint shows that the proposed method has a potential to address the patient's psychosocial concerns and minimize the exposure of the finger loss to the public.Comment: Open Access articl

Combined written and oral information prior to gastrointestinal endoscopy compared with oral information alone: a randomized trial

BACKGROUND: Little is known about how to most effectively deliver relevant information to patients scheduled for endoscopy. METHODS: To assess the effects of combined written and oral information, compared with oral information alone on the quality of information before endoscopy and the level of anxiety. We designed a prospective study in two Swiss teaching hospitals which enrolled consecutive patients scheduled for endoscopy over a three-month period. Patients were randomized either to receiving, along with the appointment notice, an explanatory leaflet about the upcoming examination, or to oral information delivered by each patient's doctor. Evaluation of quality of information was rated on scales between 0 (none received) and 5 (excellent). The analysis of outcome variables was performed on the basis of intention to treat-analysis. Multivariate analysis of predictors of information scores was performed by linear regression analysis. RESULTS: Of 718 eligible patients 577 (80%) returned their questionnaire. Patients who received written leaflets (N = 278) rated the quality of information they received higher than those informed verbally (N = 299), for all 8 quality-of-information items. Differences were significant regarding information about the risks of the procedure (3.24 versus 2.26, p < 0.001), how to prepare for the procedure (3.56 versus 3.23, p = 0.036), what to expect after the procedure (2.99 versus 2.59, p < 0.001), and the 8 quality-of-information items (3.35 versus 3.02, p = 0.002). The two groups reported similar levels of anxiety before procedure (p = 0.66), pain during procedure (p = 0.20), tolerability throughout the procedure (p = 0.76), problems after the procedure (p = 0.22), and overall rating of the procedure between poor and excellent (p = 0.82). CONCLUSION: Written information led to more favourable assessments of the quality of information and had no impact on patient anxiety nor on the overall assessment of the endoscopy. Because structured and comprehensive written information is perceived as beneficial by patients, gastroenterologists should clearly explain to their patients the risks, benefits and alternatives of endoscopic procedures. Trial registration: Current Controlled trial number: ISRCTN34382782

The effectiveness of early lens extraction with intraocular lens implantation for the treatment of primary angle-closure glaucoma (EAGLE) : study protocol for a randomized controlled trial

Peer reviewedPublisher PD

Reliability of two behavioral tools to assess pain in preterm neonates

CONTEXT: One of the main difficulties in adequately treating the pain of neonatal patients is the scarcity of validated pain evaluation methods for this population. OBJECTIVE: To analyze the reliability of two behavioral pain scales in neonates. TYPE OF STUDY: Cross-sectional. SETTING: University hospital neonatal intensive care unit. PARTICIPANTS: 22 preterm neonates were studied, with gestational age of 34 ± 2 weeks, birth weight of 1804 ± 584 g, 68% female, 30 ± 12 hours of life, and 30% intubated. PROCEDURES: Two neonatologists (A and B) observed the patients at the bedside and on video films for 10 minutes. The Neonatal Facial Coding System and the Clinical Scoring System were scored at 1, 5, and 10 minutes. The final score was the median of the three values for each observer and scale. A and B were blinded to each other. Video assessments were made three months after bedside evaluations. MAIN MEASUREMENTS: End scores were compared between the observers using the intraclass correlation coefficient and bias analysis (paired t test and signal test). RESULTS: For the Neonatal Facial Coding System, at the bedside and on video, A and B showed a significant correlation of scores (intraclass correlation score: 0.62), without bias between them (t test and signal test: p > 0.05). For the Clinical Scoring System bedside assessment, A and B showed correlation of scores (intraclass correlation score: 0.55), but bias was also detected between them: A scored on average two points higher than B (paired t test and signal test: p 0,05). Para a Escala de Conforto Clínico à beira do leito, os escores obtidos por A e B mostraram uma correlação significante (0,55), foi detectado: o escore obtido por A foi, em média, dois pontos superior ao de B (teste t e do sinal: p < 0,05). Para a mesma escala aplicada em vídeo, os escores obtidos por A e B não mostraram correlação (0,25) e detectou-se viés (teste t e do sinal: p < 0,05). CONCLUSÃO: Os resultados reforçam a confiabilidade do Sistema de Codificação da Atividade Facial Neonatal aplicado à beira do leito para a avaliação da dor no recém-nascido pré-termo.Universidade Federal de São Paulo (UNIFESP) Escola Paulista de MedicinaUniversidade Federal de São Paulo (UNIFESP) Escola Paulista de Medicina Neonatal DivisionUniversidade Federal de São Paulo (UNIFESP) Escola Paulista de Medicina Department of EpidemiologyUNIFESP, EPM, Neonatal DivisionUNIFESP, EPM, Department of EpidemiologySciEL

Pharmacological levels of withaferin A (Withania somnifera) trigger clinically relevant anticancer effects specific to triple negative breast cancer cells

Withaferin A (WA) isolated from Withania somnifera (Ashwagandha) has recently become an attractive phytochemical under investigation in various preclinical studies for treatment of different cancer types. In the present study, a comparative pathway-based transcriptome analysis was applied in epithelial-like MCF-7 and triple negative mesenchymal MDA-MB-231 breast cancer cells exposed to different concentrations of WA which can be detected systemically in in vivo experiments. Whereas WA treatment demonstrated attenuation of multiple cancer hallmarks, the withanolide analogue Withanone (WN) did not exert any of the described effects at comparable concentrations. Pathway enrichment analysis revealed that WA targets specific cancer processes related to cell death, cell cycle and proliferation, which could be functionally validated by flow cytometry and real-time cell proliferation assays. WA also strongly decreased MDA-MB-231 invasion as determined by single-cell collagen invasion assay. This was further supported by decreased gene expression of extracellular matrix-degrading proteases (uPA, PLAT, ADAM8), cell adhesion molecules (integrins, laminins), pro-inflammatory mediators of the metastasis-promoting tumor microenvironment (TNFSF12, IL6, ANGPTL2, CSF1R) and concomitant increased expression of the validated breast cancer metastasis suppressor gene (BRMS1). In line with the transcriptional changes, nanomolar concentrations of WA significantly decreased protein levels and corresponding activity of uPA in MDA-MB-231 cell supernatant, further supporting its anti-metastatic properties. Finally, hierarchical clustering analysis of 84 chromatin writer-reader-eraser enzymes revealed that WA treatment of invasive mesenchymal MDA-MB-231 cells reprogrammed their transcription levels more similarly towards the pattern observed in non-invasive MCF-7 cells. In conclusion, taking into account that sub-cytotoxic concentrations of WA target multiple metastatic effectors in therapy-resistant triple negative breast cancer, WA-based therapeutic strategies targeting the uPA pathway hold promise for further (pre)clinical development to defeat aggressive metastatic breast cancer

Introduced Pathogens and Native Freshwater Biodiversity: A Case Study of Sphaerothecum destruens

A recent threat to European fish diversity was attributed to the association between an intracellular parasite, Sphaerothecum destruens, and a healthy freshwater fish carrier, the invasive Pseudorasbora parva originating from China. The pathogen was found to be responsible for the decline and local extinction of the European endangered cyprinid Leucaspius delineatus and high mortalities in stocks of Chinook and Atlantic salmon in the USA. Here, we show that the emerging S. destruens is also a threat to a wider range of freshwater fish than originally suspected such as bream, common carp, and roach. This is a true generalist as an analysis of susceptible hosts shows that S. destruens is not limited to a phylogenetically narrow host spectrum. This disease agent is a threat to fish biodiversity as it can amplify within multiple hosts and cause high mortalities

Premature Discontinuation of Prospective Clinical Studies Approved by a Research Ethics Committee - A Comparison of Randomised and Non-Randomised Studies.

Premature discontinuation of clinical studies affects about 25% of randomised controlled trials (RCTs) which raises concerns about waste of scarce resources for research. The risk of discontinuation of non-randomised prospective studies (NPSs) is yet unclear. To compare the proportion of discontinued studies between NPSs and RCTs that received ethical approval. We systematically surveyed prospective longitudinal clinical studies that were approved by a single REC in Freiburg, Germany between 2000 and 2002. We collected study characteristics, identified subsequent publications, and surveyed investigators to elucidate whether a study was discontinued and, if so, why. Of 917 approved studies, 547 were prospective longitudinal studies (306 RCTs and 241 NPSs). NPSs were on average smaller than RCTs, more frequently single centre and pilot studies, and less frequently funded by industry. NPSs were less frequently discontinued than RCTs: 32/221 (14%) versus 78/288 (27%, p&lt;0.001, missing data excluded). Poor recruitment was the most frequent reason for discontinuation in both NPSs (36%) and RCTs (37%). Compared to RCTs, NPSs were at lower risk for discontinuation. Measures to reliably predict, sustain, and stimulate recruitment could prevent discontinuation of many RCTs but also of some NPSs