Vicarious liability has been introduced in Scottish environmental law to strengthen the fight against wildlife crime, in particular against birds of prey. Accordingly, landowners can now incur ...liability for wildlife crime perpetrated by the landowners' employees. Conservation organisations have lauded this development, and this raises the question of whether a similar application of vicarious liability in South African environmental law could enhance the legal conservation status of birds of prey. Vicarious liability is well established in the South African law of delict but is controversial in the context of criminal law. South African environmental law already makes provision for a form of vicarious liability, inter alia also against wildlife crime, but this liability is not strict like the traditional form of vicarious liability known in the law of delict and can accordingly only be referred to as vicarious liability in a wider sense. Unlike traditional strict vicarious liability, which is regarded as undesirable in criminal law by the courts and authors, the wider form of vicarious liability in environmental law may well pass constitutional muster. Nonetheless, the direct liability of a landowner, based on a statutory legal duty to prevent the perpetration of wildlife crime by its employees, would arguably be a more satisfactory solution.
Purpose
Clinically observed discrepancies between electrocardiogram findings and subjective report of symptoms related to atrial fibrillation (AF) often remain unexplained. One could hypothesize that ...after a technically successful ablation, preoperative panic behavior might affect the report of AF-related symptoms. However, research on comorbid panic behavior in patients with AF is limited.
Methods
In this observational prospective cohort study, we investigated psychological characteristics, in particular the prevalence of panic features, among 112 patients with AF and its possible influence on experienced outcome of subsequent ablation treatment.
Results
Twelve percent of the AF patients (
n
= 12) were pre-operatively characterized by panic features. This group experienced higher levels of distress and more limitations in daily life compared to AF patients without panic features, but was not characterized by higher levels of neuroticism. However, AF-ablation resulted in a similar reduction of experienced limitations in daily functioning and levels of distress in both groups.
Conclusion
Patients with panic features experience more distress and more limitations in daily life from AF, but these complaints are reduced by AF ablation in a similar rate as in patients without panic features. Additional psychological therapy is suggested as a method to further reduce subjective AF disease burden in these patients.
Potential harmful effects of ventilation therapy could be reduced by model-based predictions of the effects of ventilator settings to the patient. To obtain optimal predictions, the model has to be ...individualized based on patients' data. Given a nonlinear model, the result of parameter identification using iterative numerical methods depends on initial estimates. In this work, a feasible hierarchical identification process is proposed and compared to the commonly implemented direct approach with randomized initial values. The hierarchical approach is exemplarily illustrated by identifying the viscoelastic model (VEM) of respiratory mechanics, whose a priori identifiability was proven. To demonstrate its advantages over the direct approach, two different data sources were employed. First, correctness of the approach was shown with simulation data providing controllable conditions. Second, the clinical potential was evaluated under realistic conditions using clinical data from 13 acute respiratory distress syndrome (ARDS) patients. Simulation data revealed that the success rate of the direct approach exponentially decreases with increasing deviation of the initial estimates while the hierarchical approach always obtained the correct solution. The average computing time using clinical data for the direct approach equals 4.77 s (SD = 1.32) and 2.41 s (SD = 0.01) for the hierarchical approach. These investigations demonstrate that a hierarchical approach may be beneficial with respect to robustness and efficiency using simulated and clinical data.
We identify 42 "candidate groups" lying between 1.8 < z < 3.0 from a sample of 3502 galaxies with spectroscopic redshifts in the zCOSMOS-deep redshift survey within this same redshift interval. Based ...on extensive analysis of mock catalogs that have been generated from the Millennium simulation, we examine the likely nature of these systems at the time of observation, and what they will evolve into down to the present epoch. We also examine present-day halos and ask whether their progenitors would have been seen among our candidate groups. There is a clear excess of massive galaxies above 10sup 10 M around the locations of the candidate groups in a large independent COSMOS photo-z sample, but we see no evidence in this latter data for any color differentiation with respect to the field. This is, however, consistent with the idea that such differentiation arises in satellite galaxies, as indicated at z < 1, if the candidate groups are indeed only starting to be assembled.
We examine the red fraction of central and satellite galaxies in the large zCOSMOS group catalog out to z Asymptotically = to 0.8, correcting for both the incompleteness in stellar mass and for the ...less than perfect purities of the central and satellite samples. We show that at all masses and at all redshifts, the fraction of satellite galaxies that have been quenched, i.e., that are red, is systematically higher than that of centrals, as seen locally in the Sloan Digital Sky Survey (SDSS). The satellite quenching efficiency, which is the probability that a satellite is quenched because it is a satellite rather than a central, is, as locally, independent of stellar mass. Furthermore, the average value is about 0.5, which is also very similar to that seen in the SDSS. We also construct the mass functions of blue and red centrals and satellites and show that these broadly follow the predictions of the Peng et al. analysis of the SDSS groups. Together, these results indicate that the effect of the group environment in quenching satellite galaxies was very similar to what it is today when the universe was about half its present age.
Context. Nearly 100 new strong-lens candidates have been discovered in the COSMOS field. Among these, 20 lens candidates with 0.34 ≲ zlens ≲ 1.13 feature multiple images of background sources. Aims. ...Using the multi-wavelength coverage of the field and its spectroscopic follow-up, we characterize the evolution with redshift of the environment and of the dark-matter (DM) fraction of the lens galaxies. Methods. We present spectroscopic and new photometric redshifts of the strong-lens candidates. The lens environment is characterized in the following way: we account for the projected 10 closest galaxies around each lens and for galaxies with a projected distance less than 1 Mpc at the lens galaxy redshift. In both cases, we perform similar measurements on a control sample of “twin” non-lens early-type galaxies (ETGs). In addition, we identify group members and field galaxies in the X-ray and optical catalogs of galaxy groups and clusters. From those catalogs, we measure the external shear contribution of the groups/clusters surrounding the lens galaxies. The systems are then modeled using a singular isothermal ellipsoid for the lens galaxies plus the external shear produced by the groups/clusters. Results. We observe that the average stellar mass of lens galaxies increases with redshift. In addition, we measure that the environment of lens galaxies is compatible with that of the twins over the whole redshift range tested here. During the lens modeling, we notice that when let free, the external shear points in a direction which is the mean direction of the external shear produced by the groups/clusters and of the closest galaxy to the lens. We also notice that the DM fraction of the lens galaxies measured within the Einstein radius significantly decreases as the redshift increases. Conclusions. Given these observations, we conclude that while the environment of lens galaxies is compatible with that of non-lens ETGS over a wide range of redshifts, their mass properties evolves significantly with redshift: it is still not clear whether this advocates in favor of a stronger lensing bias toward massive objects at high redshift or if it is simply representative of the high proportion of massive and high stellar density galaxies at high redshift.
Introduction: species, environmental law and the danger of misidentification Species are important in environmental law. Legislation bestowing protection on various components of biodiversity ...typically contains lists of species, divided into different categories such as "Endangered", "Threatened"; "Protected" and so forth. Such categories of species are then made subject to varying degrees of legal protection. Exceptions exist where species are not mentioned by name, but are rather included in defined groups. For instance, the relevant legislation may provide that all indigenous vertebrate animals in a given area of jurisdiction are legally protected. Nevertheless, species-based legal protection remains a pervasive feature of biodiversity legislation. Species-based legal protection is the norm rather than the exception in South Africa too, and national and provincial laws typically incorporate lists of species.
We study the spatial clustering of 538 X-ray selected AGN in the 2 deg2 XMM-COSMOS field that are spectroscopically identified with I_AB<23 and span the redshift range z=0.2-3.0. The median redshift ...and X-ray luminosity of the sample are z = 0.98 and L0.5-10=6.3× 1043 erg s-1, respectively. A strong clustering signal is detected at 18σ level, which is the most significant measurement obtained to date for clustering of X-ray selected AGN. By fitting the projected correlation function w(r_p) with a power law on scales of r_p=0.3-40 h-1 Mpc, we derive a best-fit comoving correlation length of r0 = 8.6±0.5 h-1 Mpc and slope of γ=1.88±0.07 (Poissonian errors; bootstrap errors are about a factor of 2 larger). An excess signal is observed in the range r_p˜5-15 h-1 Mpc, which is due to a large-scale structure at z˜ 0.36 containing about 40 AGN, a feature which is evident over many wavelengths in the COSMOS field. When removing the z˜ 0.36 structure or computing w(r_p) in a narrower range around the peak of the redshift distribution (e.g. z=0.4-1.6), the correlation length decreases to r0 ˜ 5-6 h-1 Mpc, which is consistent with what is observed for bright optical QSOs at the same redshift. We investigate the clustering properties of obscured and unobscured AGN separately, adopting different definitions for the source obscuration. For the first time, we are able to provide a significant measurement for the spatial clustering of obscured AGN at z˜ 1. Within the statistical uncertainties, we do not find evidence that AGN with broad optical lines (BLAGN) cluster differently from AGN without broad optical lines (non-BLAGN). Based on these results, which are limited by object statistics, however, obscured and unobscured AGN are consistent with inhabiting similar environments. The evolution of AGN clustering with redshift is also investigated. No significant difference is found between the clustering properties of XMM-COSMOS AGN at redshifts below or above z=1. The correlation length measured for XMM-COSMOS AGN at z˜ 1 is similar to that of massive galaxies (stellar mass M_star⪆ 3× 1010 Mȯ) at the same redshift. This suggests that AGN at z˜ 1 are preferentially hosted by massive galaxies, as observed both in the local and in the distant (z˜ 2) Universe. According to a simple clustering evolution scenario, we find that the relics of AGN are expected to have a correlation length as large as r0 ˜ 8 h-1 Mpc by z=0, and hence to be hosted by local bright (L˜ L_star) ellipticals. We make use of dark matter halo catalogs from the Millennium simulation to determine the typical halo hosting moderately luminous z˜ 1 AGN. We find that XMM-COSMOS AGN live in halos with masses M⪆ 2.5× 1012 Mȯ h-1. By combining the number density of XMM-COSMOS AGN to that of the hosting dark matter halos we estimate the AGN duty cycle and lifetimes. We find lifetimes approximately of 1 Gyr for AGN at z˜ 1, which are longer than those estimated for optically bright QSOs at the same redshift. These longer lifetimes mainly reflect the higher number density of AGN selected by X-ray samples.
Context. Strong lens candidates have been newly identified within the COSMOS field. We present VLT/FORS1 spectroscopic follow-up observations and HST/WFPC2 imaging of the system COSMOS 5921+0638, ...which exhibits quadruply lensed images and a perfect Einstein ring. Aims. We investigate the nature of COSMOS 5921+0638 by studying its photometric, spectroscopic and physical properties. Methods. By analyzing our VLT/FORS1 spectroscopy and Subaru/CFHT/HST imaging of COSMOS 5921+0638, we completed both an environmental analysis and detailed analytical and grid-based mass modeling to determine it properties. Results. We measured the redshifts of the lensing galaxy in COSMOS 5921+0638 (zl = 0.551 ± 0.001) and 9 additional galaxies in the field (5 of them at z ~ 0.35). The redshift of the lensed source was inferred by identifying a candidate Lyα line at zs = 3.14 ± 0.05. The mass modeling reveals the requirement of a small external shear (γ = 0.038), which is slightly larger than the lensing contribution expected by galaxy groups along the line-of-sight obtained from the zCOSMOS optical group catalog ($\kappa_{\rm groups}$ ~ 0.01 and $\gamma_{\rm groups}$ ~ 0.005). The estimated time-delays between the different images are of the order of hours to half a week and the total magnification of the background source is μ ≈ 150. The measured mass-to-light ratio of the lensing galaxy within the Einstein ring is $M/L_B$ ≈ 8.5 ± 1.6. Anomalies are observed between the measured and expected flux ratios of the images of the background AGN. Conclusions. Our analysis indicates that the ring and point-like structures in COSMOS 5921+0638 consist of a lensed high redshift galaxy hosting a low luminosity AGN (LLAGN). The observed flux ratio anomalies are probably due to microlensing by stars in the lensing galaxy and/or a combination of static phenomena. Multi-epoch, multi-band space-based observations would allow us to differentiate between the possible causes of these anomalies, since static and/or dynamic variations could be identified. Because of its short time-delays and the possibility of microlensing, COSMOS 5921+0638 is a promising laboratory for future studies of LLAGNs.
Prediction of ligand binding and design of new function in enzymes is a time-consuming and expensive process. Crystallography gives the impression that proteins adopt a fixed shape, yet enzymes are ...functionally dynamic. Molecular dynamics offers the possibility of probing protein movement while predicting ligand binding. Accordingly, we choose the bacterial F1Fo ATP synthase ε subunit to unravel why ATP affinity by ε subunits from Bacillus subtilis and Bacillus PS3 differs ~500-fold, despite sharing identical sequences at the ATP-binding site.
We first used the Bacillus PS3 ε subunit structure to model the B. subtilis ε subunit structure and used this to explore the utility of molecular dynamics (MD) simulations to predict the influence of residues outside the ATP binding site. To verify the MD predictions, point mutants were made and ATP binding studies were employed.
MD simulations predicted that E102 in the B. subtilis ε subunit, outside of the ATP binding site, influences ATP binding affinity. Engineering E102 to alanine or arginine revealed a ~10 or ~54 fold increase in ATP binding, respectively, confirming the MD prediction that E102 drastically influences ATP binding affinity.
These findings reveal how MD can predict how changes in the “second shell” residues around substrate binding sites influence affinity in simple protein structures. Our results reveal why seemingly identical ε subunits in different ATP synthases have radically different ATP binding affinities.
This study may lead to greater utility of molecular dynamics as a tool for protein design and exploration of protein design and function.
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