27 research outputs found
Evolution of aerial spider webs coincided with repeated structural optimization of silk anchorages
Physical structures built by animals challenge our understanding of biological processes and inspire the development of smart materials and green architecture. It is thus indispensable to understand the drivers, constraints, and dynamics that lead to the emergence and modification of building behavior. Here, we demonstrate that spider web diversification repeatedly followed strikingly similar evolutionary trajectories, guided by physical constraints. We found that the evolution of suspended webs that intercept flying prey coincided with small changes in silk anchoring behavior with considerable effects on the robustness of web attachment. The use of nanofiber based capture threads (cribellate silk) conflicts with the behavioral enhancement of web attachment, and the repeated loss of this trait was frequently followed by physical improvements of web anchor structure. These findings suggest that the evolution of building behavior may be constrained by major physical traits limiting its role in rapid adaptation to a changing environment
Obesity in total hip arthroplasty—does it really matter?: A meta-analysis
Discussion persists as to whether obesity negatively influences the outcome of hip arthroplasty. We performed a meta-analysis with the primary research question of whether obesity has a negative effect on short- and long-term outcome of total hip arthroplasty. We searched the literature and included studies comparing the outcome of hip arthroplasty in different weight groups. The methodology of the studies included was scored according to the Cochrane guidelines. We extracted and pooled the data. For continuous data, we calculated a weighted mean difference and for dichotomous variables we calculated a weighted odds ratio (OR). Heterogeneity was calculated using I(2) statistics. 15 studies were eligible for data extraction. In obese patients, dislocation of the hip (OR = 0.54, 95% CI: 0.38-0.75) (10 studies, n = 8,634), aseptic loosening (OR = 0.64, CI: 0.43-0.96) (6 studies, n = 5,137), infection (OR = 0.3, CI: 0.19-0.49) (10 studies, n = 7,500), and venous thromboembolism (OR = 0.56, CI: 0.32-0.98) (7 studies, n = 3,716) occurred more often. Concerning septic loosening and intraoperative fractures, no statistically significant differences were found, possibly due to low power. Subjective outcome measurements did not allow pooling because of high heterogeneity (I(2) = 68%). Obesity appears to have a negative influence on the outcome of total hip replacemen
Selective phosphodiesterase inhibitors: a promising target for cognition enhancement
# The Author(s) 2008. This article is published with open access at Springerlink.com Rationale One of the major complaints most people face during aging is an impairment in cognitive functioning. This has a negative impact on the quality of daily life and is even more prominent in patients suffering from neurodegenerative and psychiatric disorders including Alzheimer’s disease, schizophrenia, and depression. So far, the majority of cognition enhancers are generally targeting one particular neurotransmitter system. However, recently phosphodiesterases (PDEs) have gained increased attention as a potential new target for cognition enhancement. Inhibition of PDEs increases the intracellular availability of the second messengers cGMP and/or cAMP. Objective The aim of this review was to provide an overvie
Anterolateral Ligament Expert Group consensus paper on the management of internal rotation and instability of the anterior cruciate ligament - deficient knee
Purpose of this paper is to provide an overview of the latest research on the anterolateral ligament (ALL) and present the consensus of the ALL Expert Group on the anatomy, radiographic landmarks, biomechanics, clinical and radiographic diagnosis, lesion classification, surgical technique and clinical outcomes. A consensus on controversial subjects surrounding the ALL and anterolateral knee instability has been established based on the opinion of experts, the latest publications on the subject and an exchange of experiences during the ALL Experts Meeting (November 2015, Lyon, France). The ALL is found deep to the iliotibial band. The femoral origin is just posterior and proximal to the lateral epicondyle; the tibial attachment is 21.6 mm posterior to Gerdy's tubercle and 4-10 mm below the tibial joint line. On a lateral radiographic view the femoral origin is located in the postero-inferior quadrant and the tibial attachment is close to the centre of the proximal tibial plateau. Favourable isometry of an ALL reconstruction is seen when the femoral position is proximal and posterior to the lateral epicondyle, with the ALL being tight upon extension and lax upon flexion. The ALL can be visualised on ultrasound, or on T2-weighted coronal MRI scans with proton density fat-suppressed evaluation. The ALL injury is associated with a Segond fracture, and often occurs in conjunction with acute anterior cruciate ligament (ACL) injury. Recognition and repair of the ALL lesions should be considered to improve the control of rotational stability provided by ACL reconstruction. For high-risk patients, a combined ACL and ALL reconstruction improves rotational control and reduces the rate of re-rupture, without increased postoperative complication rates compared to ACL-only reconstruction. In conclusion this paper provides a contemporary consensus on all studied features of the ALL. The findings warrant future research in order to further test these early observations, with the ultimate goal of improving the long-term outcomes of ACL-injured patients. Level of evidence Level V-Expert opinion
sensiPhy
1.Biological conclusions drawn from phylogenetic comparative methods can be sensitive to uncertainty in species sampling, phylogeny and data. To be confident about our conclusions, we need to quantify their robustness to such uncertainty.
2.We present sensiPhy, an R-package to easily and rapidly perform sensitivity analysis for phylogenetic comparative methods. sensiPhy allows researchers to evaluate the sampling effort, detect influential species and clades, assess phylogenetic uncertainty and quantify the effects of intraspecific variation, for phylogenetic regression and for metrics of phylogenetic signal, diversification and trait evolution.
3.Uniquely, sensiPhy allows users to simultaneously quantify the effects of different types of uncertainty and potential interactions among them.
4.Using real data, we show how conclusions from comparative methods can be affected by uncertainty and how sensiPhy can help determine if a conclusion is robust.
5.By providing a single, intuitive and user-friendly resource that can evaluate various sources of uncertainty, sensiPhy aims to encourage researchers, and particularly less experienced users, to incorporate sensitivity analyses in their phylogenetic comparative analys
sensiPhy: an R-package for sensitivity analysis in phylogenetic comparative methods
1.Biological conclusions drawn from phylogenetic comparative methods can be sensitive to uncertainty in species sampling, phylogeny and data. To be confident about our conclusions, we need to quantify their robustness to such uncertainty.
2.We present sensiPhy, an R-package to easily and rapidly perform sensitivity analysis for phylogenetic comparative methods. sensiPhy allows researchers to evaluate the sampling effort, detect influential species and clades, assess phylogenetic uncertainty and quantify the effects of intraspecific variation, for phylogenetic regression and for metrics of phylogenetic signal, diversification and trait evolution.
3.Uniquely, sensiPhy allows users to simultaneously quantify the effects of different types of uncertainty and potential interactions among them.
4.Using real data, we show how conclusions from comparative methods can be affected by uncertainty and how sensiPhy can help determine if a conclusion is robust.
5.By providing a single, intuitive and user-friendly resource that can evaluate various sources of uncertainty, sensiPhy aims to encourage researchers, and particularly less experienced users, to incorporate sensitivity analyses in their phylogenetic comparative analys
sensiPhy: an R-package for sensitivity analysis in phylogenetic comparative methods
1.Biological conclusions drawn from phylogenetic comparative methods can be sensitive to uncertainty in species sampling, phylogeny and data. To be confident about our conclusions, we need to quantify their robustness to such uncertainty. 2.We present sensiPhy, an R-package to easily and rapidly perform sensitivity analysis for phylogenetic comparative methods. sensiPhy allows researchers to evaluate the sampling effort, detect influential species and clades, assess phylogenetic uncertainty and quantify the effects of intraspecific variation, for phylogenetic regression and for metrics of phylogenetic signal, diversification and trait evolution. 3.Uniquely, sensiPhy allows users to simultaneously quantify the effects of different types of uncertainty and potential interactions among them. 4.Using real data, we show how conclusions from comparative methods can be affected by uncertainty and how sensiPhy can help determine if a conclusion is robust. 5.By providing a single, intuitive and user-friendly resource that can evaluate various sources of uncertainty, sensiPhy aims to encourage researchers, and particularly less experienced users, to incorporate sensitivity analyses in their phylogenetic comparative analys
sensiPhy: an R-package for sensitivity analysis in phylogenetic comparative methods
1.Biological conclusions drawn from phylogenetic comparative methods can be sensitive to uncertainty in species sampling, phylogeny and data. To be confident about our conclusions, we need to quantify their robustness to such uncertainty. 2.We present sensiPhy, an R-package to easily and rapidly perform sensitivity analysis for phylogenetic comparative methods. sensiPhy allows researchers to evaluate the sampling effort, detect influential species and clades, assess phylogenetic uncertainty and quantify the effects of intraspecific variation, for phylogenetic regression and for metrics of phylogenetic signal, diversification and trait evolution. 3.Uniquely, sensiPhy allows users to simultaneously quantify the effects of different types of uncertainty and potential interactions among them. 4.Using real data, we show how conclusions from comparative methods can be affected by uncertainty and how sensiPhy can help determine if a conclusion is robust. 5.By providing a single, intuitive and user-friendly resource that can evaluate various sources of uncertainty, sensiPhy aims to encourage researchers, and particularly less experienced users, to incorporate sensitivity analyses in their phylogenetic comparative analys