Abstract
We present a response to Butterworth and Ross-Gillespie's (2022) comment on our perspectives on how forage fish fisheries are impacting the endangered African penguin (Sphenicus demersus), ...and corresponding management options. Butterworth and Ross-Gillespie overstate model uncertainties and downplay the clear ecological and conservation significance of the fisheries closure experiment. We demonstrate that their criticism of “pseudo-replication” is weak, and not in line with their own analyses nor with the interpretations of many international scientific review panels commissioned by the government of South Africa to evaluate experimental results. Their comment does not alter our fundamental conclusions that forage fisheries operating near penguin breeding colonies compete with the birds for food resources, are detrimental to the penguin's population health, and are impeding recovery. Given that sardines are depleted (DFFE, 2021) and the African penguin is approaching a conservation crisis, we reiterate our position that continuing the precautionary approach of closures at the local scale of central-place foraging penguins is warranted to facilitate their population growth under fisheries management goals to conserve and maintain ecosystem functions.
Probing Cold Dense Nuclear Matter Subedi, R; Shneor, R; Monaghan, P ...
Science (American Association for the Advancement of Science),
06/2008, Letnik:
320, Številka:
5882
Journal Article
Recenzirano
Odprti dostop
The protons and neutrons in a nucleus can form strongly correlated nucleon pairs. Scattering experiments, in which a proton is knocked out of the nucleus with high-momentum transfer and high missing ...momentum, show that in carbon-12 the neutron-proton pairs are nearly 20 times as prevalent as proton-proton pairs and, by inference, neutron-neutron pairs. This difference between the types of pairs is due to the nature of the strong force and has implications for understanding cold dense nuclear systems such as neutron stars.
Peroxisome proliferator-activated receptor γ (PPARγ ) is a nuclear hormone receptor that plays a key role in the differentiation of adipocytes. Activation of this receptor in liposarcomas and breast ...and colon cancer cells also induces cell growth inhibition and differentiation. In the present study, we show that PPARγ is expressed in human prostate adenocarcinomas and cell lines derived from these tumors. Activation of this receptor with specific ligands exerts an inhibitory effect on the growth of prostate cancer cell lines. Further, we show that prostate cancer and cell lines do not have intragenic mutations in the PPARγ gene, although 40% of the informative tumors have hemizygous deletions of this gene. Based on our preclinical data, we conducted a phase II clinical study in patients with advanced prostate cancer using troglitazone, a PPARγ ligand used for the treatment of type 2 diabetes. Forty-one men with histologically confirmed prostate cancer and no symptomatic metastatic disease were treated orally with troglitazone. An unexpectedly high incidence of prolonged stabilization of prostate-specific antigen was seen in patients treated with troglitazone. In addition, one patient had a dramatic decrease in serum prostate-specific antigen to nearly undetectable levels. These data suggest that PPARγ may serve as a biological modifier in human prostate cancer and its therapeutic potential in this disease should be further investigated.
Aspirin products are known to cause irritation and injury to the gastric mucosa. The belief that enteric-coated and buffered varieties are less likely to occasion major upper-gastrointestinal ...bleeding (UGIB) than plain aspirin was tested in data from a multicentre case-control study.
550 incident cases of UGIB admitted to hospital with melaena or haematemesis and confirmed by endoscopy, and 1202 controls identified from population census lists, were interviewed about use of aspirin and other non-steroidal anti-inflammatory drugs (NSAIDs) during the 7 days before the onset of bleeding (cases) or interview (controls). Relative risks of UGIB for each type of aspirin used regularly (at least every other day) were calculated overall, and according to dose, by multiple logistic regression, with control for age, sex, marital status, date, education, cigarette smoking, alcohol use, and use of NSAIDs.
The relative risks of UGIB for plain, enteric-coated, and buffered aspirin at average daily doses of 325 mg or less were 2·6, 2·7, and 3·1, respectively. At doses greater than 325 mg, the relative risk was 5·8 for plain and 7·0 for buffered aspirin; there were insufficient data to evaluate enteric-coated aspirin at this dose level. There were no important differences in risk attributable to the three aspirin forms according to bleeding site (gastric
vs duodenal), or when users of NSAIDs were excluded.
Use of low doses of enteric-coated or buffered aspirin carries a three-fold increase in the risk of major UGIB. The assumption that these formulations are less harmful than plain aspirin may be mistaken.
Toxic epidermal necrolysis and Stevens–Johnson syndrome are acute life-threatening conditions. Epidermal necrosis causes erosions of the mucous membranes, extensive detachment of the epidermis, and ...severe constitutional symptoms.
1
,
2
The physiopathologic mechanisms of these conditions are not established. When there is very extensive skin detachment (Figure 1) and a poor prognosis (death rates of 30 to 40 percent), the condition is usually called toxic epidermal necrolysis. Milder forms are known as Stevens–Johnson syndrome (Figure 2) or overlapping Stevens– Johnson syndrome and toxic epidermal necrolysis.
3
Toxic epidermal necrolysis is usually drug-related.
1
,
2
Drugs are an important cause of Stevens–Johnson syndrome, but infections . . .
Spatial variation in abundance has been attributed to habitat heterogeneity and patchiness. Our goal in this research was to understand what factors were associated with spatial patterns of habitat ...use by Elliot’s short-tailed shrews (
Blarina hylophaga
Elliot, 1899) in tallgrass prairie. Our modeling efforts were based on 20 years (1981–2000) of presence–absence data for shrews at each of 20 stations (local site) along 14 permanent traplines on Konza Prairie Biological Station, Kansas, USA. A logistic model accurately predicted the presence of short-tailed shrews at a local site. Probability of shrew occurrence decreased as amount of precipitation decreased, slope steepness increased, grazing increased, or burned area within 500 m of a local site increased. However, when amount of precipitation was low, area burned was high, or grazing occurred, shrews were uncommon and responded little to the other variables. Numbers of shrews were negatively related only to numbers of deer mice (
Peromyscus maniculatus
(Wagner, 1845)), a mouse that selects burned and grazed habitats that shrews avoid. Our observations suggest that multiple environmental factors limit use of local sites, whereas competition with other species does not. Our results can inform decisions related to conservation of biodiversity given management practices in this endangered ecosystem.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Sn ejecta particle-size distributions from the break-up of a microsheet in a vacuum will be presented. The micro-sheet was created from a high explosive driven shock wave passing through a precision ...groove machined into a Sn sample. The particle-size measurements were carried out using an ultraviolet in-line Fraunhofer holography diagnostic. The diagnostic will be presented along with particle-size distributions over most of the ejecta velocities throughout the microsheet.
Hyperhomocysteinemia is an independent risk factor for cardiovascular disease and accelerates atherosclerosis in apoE–/– mice. Despite the observations that homocysteine causes endoplasmic reticulum ...(ER) stress and programmed cell death (PCD) in cultured human vascular endothelial cells, the cellular factors responsible for this effect and their relevance to atherogenesis have not been completely elucidated. We report here that homocysteine induces the expression of T-cell death-associated gene 51 (TDAG51), a member of the pleckstrin homology-related domain family, in cultured human vascular endothelial cells. This effect was observed for other ER stress-inducing agents, including dithiothreitol and tunicamycin. TDAG51 expression was attenuated in homozygous A/A mutant eukaryotic translation initiation factor 2α mouse embryonic fibroblasts treated with homocysteine or tunicamycin, suggesting that ER stress-induced phosphorylation of eukaryotic translation initiation factor 2α is required for TDAG51 transcriptional activation. Transient overexpression of TDAG51 elicited significant changes in cell morphology, decreased cell adhesion, and promoted detachment-mediated PCD. In support of these in vitro findings, TDAG51 expression was increased and correlated with PCD in the atherosclerotic lesions from apoE–/– mice fed hyperhomocysteinemic diets, compared with mice fed a control diet. Collectively, these findings provide evidence that TDAG51 is induced by homocysteine, promotes detachment-mediated PCD, and contributes to the development of atherosclerosis observed in hyperhomocysteinemia.
Department of Neurosurgery, University of Iowa, Iowa City, Iowa 52242
Submitted 27 June 2003;
accepted in final form 24 March 2004
The inferior frontal gyrus (IFG) of humans is known to play a ...critical role in speech production. The IFG is a highly convoluted and cytoarchitectonically diverse structure, classically forming 3 subgyri. It is reasonable to speculate that during speaking the IFG, or some portion of it, influences by corticocortical connections the orofacial representational area of primary motor cortex. To test the hypothesis that such corticocortical connections exist, electrical-stimulation tract tracing experiments were performed intraoperatively on 14 human subjects undergoing surgical treatment of medically intractable epilepsy. Bipolar electrical stimulation was applied to sites on the IFG, while the resulting evoked potentials were recorded from orofacial motor cortex, using a multichannel recording array. Stimulation of the IFG evoked polyphasic waveforms on motor cortex of both language-dominant and -nondominant hemispheres. The evoked waveforms had consistent features across subjects. The responses were seen in discrete regions on precentral cortex. Stimulation of motor cortex also evoked responses on portions of IFG. The data provide evidence for a functional connection between the human IFG and orofacial motor cortex.
Address for reprint requests and other correspondence: J.D.W. Greenlee, Department of Neurosurgery, University of Iowa Hospitals and Clinics, 200 West Hawkins Drive, Iowa City, IA 52242 (E-mail: jeremy-greenlee{at}uiowa.edu ).
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