1,106 research outputs found
The relationship between tornadic and nontornadic convective wind fatalities and warnings
A database of tornado fatalities, nontornadic convective wind fatalities, severe thunderstorm warnings,
and tornado warnings was compiled for the period 1986â2007 to assess the spatial and temporal distribution
of warned and unwarned fatalities. The time of fatality and location as reported in Storm Data was compared
to tornado and severe thunderstorm warnings to determine if a warning was in effect when the fatality
occurred. Overall, 23.7% of tornado fatalities were unwarned, while 53.2% of nontornadic convective wind
fatalities were unwarned. Most unwarned tornado fatalities occurred prior to the mid-1990sâcoinciding
with modernization of the National Weather Serviceâwhile unwarned nontornadic convective wind fa-
talities remained at a relatively elevated frequency throughout the study period. Geographic locations with
high numbers of unwarned tornado and nontornadic convective wind fatalities were associated with one
high-magnitude event that was unwarned rather than a series of smaller unwarned events over the period.
There are many factors that contribute to warning response by the public, and the issuance of a severe
thunderstorm or tornado warning is an important initial step in the warning process. A better understanding
of the characteristics of warned and unwarned fatalities is important to future reduction of unwarned
fatalities
Lead (Pb) concentrations in predatory bird livers 2010 and 2011: a Predatory Bird Monitoring Scheme (PBMS) report
The Predatory Bird Monitoring Scheme (PBMS; http://pbms.ceh.ac.uk/) is the umbrella project that encompasses the Centre for Ecology & Hydrologyâs National Capability contaminant monitoring and surveillance work on avian predators. By monitoring sentinel vertebrate species, the PBMS aims to detect and quantify current and emerging chemical threats to the environment and in particular to vertebrate wildlife.
Lead (Pb) is a highly toxic metal that acts as a non-specific poison affecting all body systems and has no known biological requirement. Sources of Pb in the environment include lead mining, the refining and smelting of lead and other metals, the manufacture and use of alkyl lead fuel additives, and the use of lead ammunition.
The present study is the first two years of a PBMS monitoring programme to quantify the scale of exposure to [and associated risk from] Pb in predatory birds. The aim is to quantify the extent of exposure to lead [as assessed from liver residues] in two predatory bird species, the red kite (Mivus milvus) and the sparrowhawk (Accipiter nisus). The red kite is a scavenger and, as such, is particularly at risk from consumption of Pb ammunition in unretrieved game. Sparrowhawks prey predominantly upon live passerine birds that are unlikely to be shot in the UK; likely sources of exposure are diffuse Pb contamination although some individuals may also be exposed to Pb particles ingested by their prey. We also examined the liver Pb isotope ratios in to explore whether they can be used to ascribe likely sources of any Pb detected in the birds.
Red kites had significantly higher Pb concentration than those measured in sparrowhawks but the majority of sparrowhawks and all the red kites had liver Pb concentrations below those thought to cause clinical and sub-clinical adverse effects in Falconiforme species. There was overlap in the liver Pb isotope ratios of red kites and sparrowhawks yet there was evidence of separation between the two species. There was also evidence of overlap with the isotope signature for coal and for Pb shot but the isotope signatures in the bird livers were distinct from
that of petrol Pb. The Pb isotope pattern observed in the red kites and sparrowhawks in the current study may reflect the fact that liver Pb concentrations were low in the small sample of birds that were analysed and may have been a result of exposure to low-level, diffuse contamination.birds.
Red kites had significantly higher Pb concentration than those measured in sparrowhawks but
the majority of sparrowhawks and all the red kites had liver Pb concentrations below those
thought to cause clinical and sub-clinical adverse effects in Falconiforme species. There was
overlap in the liver Pb isotope ratios of red kites and sparrowhawks yet there was evidence of
separation between the two species. There was also evidence of overlap with the isotope
signature for coal and for Pb shot but the isotope signatures in the bird livers were distinct from
that of petrol Pb. The Pb isotope pattern observed in the red kites and sparrowhawks in the
current study may reflect the fact that liver Pb concentrations were low in the small sample of
birds that were analysed and may have been a result of exposure to low-level, diffuse
contamination
Addendum to âAnticoagulant rodenticides in predatory birds 2007 & 2008: a Predatory Bird Monitoring Scheme (PBMS) reportâ
Simultaneous intracranial EEG and fMRI of interictal epileptic discharges in humans
Simultaneous scalp EEGâfMRI measurements allow the study of epileptic networks and more generally, of the coupling between neuronal activity and haemodynamic changes in the brain. Intracranial EEG (icEEG) has greater sensitivity and spatial specificity than scalp EEG but limited spatial sampling. We performed simultaneous icEEG and functional MRI recordings in epileptic patients to study the haemodynamic correlates of intracranial interictal epileptic discharges (IED).
Two patients undergoing icEEG with subdural and depth electrodes as part of the presurgical assessment of their pharmaco-resistant epilepsy participated in the study. They were scanned on a 1.5 T MR scanner following a strict safety protocol. Simultaneous recordings of fMRI and icEEG were obtained at rest. IED were subsequently visually identified on icEEG and their fMRI correlates were mapped using a general linear model (GLM).
On scalp EEGâfMRI recordings performed prior to the implantation, no IED were detected. icEEGâfMRI was well tolerated and no adverse health effect was observed. intra-MR icEEG was comparable to that obtained outside the scanner. In both cases, significant haemodynamic changes were revealed in relation to IED, both close to the most active electrode contacts and at distant sites. In one case, results showed an epileptic network including regions that could not be sampled by icEEG, in agreement with findings from magneto-encephalography, offering some explanation for the persistence of seizures after surgery.
Hence, icEEGâfMRI allows the study of whole-brain human epileptic networks with unprecedented sensitivity and specificity. This could help improve our understanding of epileptic networks with possible implications for epilepsy surgery
Structure of protease-cleaved escherichia coliα-2-macroglobulin reveals a putative mechanism of conformational activation for protease entrapment
Bacterial -2-macroglobulins have been suggested to function in defence as broad-spectrum inhibitors of host proteases that breach the outer membrane. Here, the X-ray structure of protease-cleaved Escherichia coli -2-macroglobulin is described, which reveals a putative mechanism of activation and conformational change essential for protease inhibition. In this competitive mechanism, protease cleavage of the bait-region domain results in the untethering of an intrinsically disordered region of this domain which disrupts native interdomain interactions that maintain E. coli -2-macroglobulin in the inactivated form. The resulting global conformational change results in entrapment of the protease and activation of the thioester bond that covalently links to the attacking protease. Owing to the similarity in structure and domain architecture of Escherichia coli -2-macroglobulin and human -2-macroÂglobulin, this protease-activation mechanism is likely to operate across the diverse members of this group
Strong contribution to octet baryon mass splittings
We calculate the contribution to the mass splittings in baryonic
isospin multiplets using SU(3) chiral perturbation theory and lattice QCD.
Fitting isospin-averaged perturbation theory functions to PACS-CS and
QCDSF-UKQCD Collaboration lattice simulations of octet baryon masses, and using
the physical light quark mass ratio as input, allows ,
and to be evaluated from the
full SU(3) theory. The resulting values for each mass splitting are consistent
with the experimental values after allowing for electromagnetic corrections. In
the case of the nucleon, we find , with the
dominant uncertainty arising from the error in
Premature mortality in refractory partial epilepsy: does surgical treatment make a difference?
Background: Epilepsy carries an increased risk of premature death. For some people with intractable focal epilepsy, surgery offers hope for a seizure-free life. The authors aimed to see whether epilepsy surgery influenced mortality in people with intractable epilepsy. Methods: The authors audited survival status in two cohorts (those who had surgery and those who had presurgical assessment but did not have surgery). Results: There were 40 known deaths in the non-surgical group (3365 person years of follow-up) and 19 in the surgical group (3905 person-years of follow-up). Non-operated patients were 2.4 times (95% CI 1.4 to 4.2) as likely to die as those who had surgery. They were 4.5 times (95% CI 1.9 to 10.9) as likely to die a probable epilepsy-related death. In the surgical group, those with ongoing seizures 1 year after surgery were 4.0 (95% CI 1.2 to 13.7) times as likely to die as those who were seizure-free or who had only simple partial seizures. Time-dependent Cox analysis showed that the yearly outcome group did not significantly affect mortality (HR 1.3, 95% CI 0.9 to 1.8). Conclusion: Successful epilepsy surgery was associated with a reduced risk of premature mortality, compared with those with refractory focal epilepsy who did not have surgical treatment. To some extent, the reduced mortality is likely to be conferred by inducing freedom from seizures. It is not certain whether better survival is attributable only to surgery, as treatment decisions were not randomised, and there may be inherent differences between the groups.<br/
Anticoagulant rodenticides in red kites (Milvus milvus) in Britain 2010 to 2015: a Predatory Bird Monitoring Scheme (PBMS) report
The Predatory Bird Monitoring Scheme (PBMS; http://pbms.ceh.ac.uk/) is the umbrella project that encompasses the Centre for Ecology & Hydrologyâs National Capability activities for contaminant monitoring and surveillance work on avian predators. The PBMS aims to detect and quantify current and emerging chemical threats to the environment and in particular to vertebrate wildlife.
Second generation anticoagulant rodenticides (SGARs) can be toxic to all mammals and birds. The PBMS together with other studies have shown that in Britain, there is widespread exposure to SGARs in a diverse range of predators of small mammals, including red kites (Milvus milvus) which will scavenge dead rats, a target species for rodent control. Defraâs Wildlife Incident Monitoring Scheme (WIIS) and the PBMS have shown that some mortalities result from this secondary exposure. The aims of the current study were to build on our earlier results by analysing liver SGAR residues in a further 24 red kites that had been submitted to the Predatory Bird Monitoring Scheme between 2010 and 2015. We (i) assessed the scale and severity of exposure and, (ii) by combining the data with that from birds collected earlier (since 2006), we determined if age and sex affects the magnitude of liver SGARs residues accumulated in red kites.
All of the 24 red kites contained detectable liver residues of one or more SGAR, and all but one bird (96%) contained residues of more than one SGAR. Difenacoum was detected most frequently (96% of birds) but bromadiolone and brodifacoum were both also detected in a large proportion of birds (83-88%). Most (approximately 75%) of the kites had sum SGAR livers concentrations >100 ng/g wet wt. and SGAR poisoning was likely to have been the cause of death in two birds. Relatively high liver SGAR residues were also detected in four other birds but they had external signs of trauma indicating they may have died from other causes. The monitoring of SGAR residues in red kites remains important contribution to our understanding of SGAR exposure in wildlife, particularly those issues related to scavenging species
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Developing a simple risk metric for the effect of sport-related concussion and physical pain on mental health
YesRisk factors associated with depression in athletes include biological sex, physical pain, and history of sport-related concussion (SRC). Due to the well-documented benefits of sport and physical activity on mental health, athletes and non-athletes were recruited to assess any differences. Beyond this, athletes were also grouped by sport-type (contact/non-contact sports) due to the increased prevalence of pain and SRC in contact sports. To our knowledge, there has been no research on how these factors influence the likelihood of depression. In the current study, 144 participants completed a short survey on the above factors and the Center for Epidemiological Studies Depression Scale. Sixty-two of these reported a history of concussion. Logistic regression revealed all the above predictors to be significantly associated with the depression scale. Individuals that had previously sustained SRC, were experiencing greater physical pain and females were more likely to display poor mental health. However, we provide further evidence for the benefits of engaging in sport and physical activity as those that took part in sport were less likely to report depression. Therefore, this study provides a simple risk metric whereby sportspeople can make a better informed choice of their sporting participation, making their own cost/reward judgement
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