Fungal triterpenes

Structural studies on the methyl esters of the triterpene acids from the polypore Daedalea quercina have established the structure of the major component, methyl carbomethoxyacetyl-. quercinate. In common with this compound, three other esters from this fungus are 23-keto-27-carboxylic esters. The first and second of these are methyl 16-hydroxycarbomethoxyacetylquercinate and methyl 16-hydroxyquercinate respectively. The third ester, methyl carbomethoxyacetyldaedaleate, which is the first recorded triterpene based on a skeleton, is highly reactive and has not, as yet, yielded recognisable transformation products. The structure advanced for this compound is based on spectroscopic examination. A minor constituent of Daedalea quercina is thought to be methyl 25-hydroxypolyporenate C. The synthesis and properties of carbomethoxyacetyl and carboxyacetyl derivatives of triterpenes have been studied. Examination of the methyl esters of the triterpene acids from Leptoporus stipticus has established that the major component, methyl tyromycate, is methyl 3-oxolanosta-7,9(11),24-trien-26-oate. Four other compounds from this fungus have been studied. Three of these have been shown to be triterpene glucosides, the first from a fungal source, whose basic nuclei are similar to that of methyl tyromycate. The last ester from Leptoporus stipticus, methyl leptoporate, is the second example of a C32 triterpene. Leptoporus stipticus (Pers.) Quel. , when cultured on malt agar medium, produces eburicoic acid and tumulosic acid. Attempts to influence the metabolite production of this latter fungus are described

On kk-geodetic groups and graphs

We call a graph $k$-geodetic, for some $k\geq 1$, if it is connected and between any two vertices there are at most $k$ geodesics. It is shown that any hyperbolic group with a $k$-geodetic Cayley graph is virtually-free. Furthermore, in such a group the centraliser of any infinite order element is an infinite cyclic group. These results were known previously only in the case that $k=1$. A key tool used to develop the theorem is a new graph theoretic result concerning ``ladder-like structures'' in a $k$-geodetic graph.Comment: 12 pages, 11 figure

Unfinished Beliefs: Three Stories and an Essay

Unfinished Beliefs, is a collection of three short stories and an essay written for the Western Washington University Honors Senior Project. Lightweight My Stall Spiro\u27s Mountain Spiritus Mund

Body size as a driver of scavenging in theropod dinosaurs

This work was funded by the Earth and Natural Sciences Doctoral Studies Programme and the Higher Education Authority through the Programme for Research at Third Level Institutions, Cycle 5 (PRTLI‐5), and cofunded by the European Regional Development Fund (K.H.) and Trinity College Dublin and the Irish Research Council (A.K.).Theropod dinosaurs dominated Earth’s terrestrial ecosystem as a diverse group of predators for more than 160 million years, yet little is known about their foraging ecology. Maintaining a balanced energy budget presented a major challenge for therapods, which ranged from the chicken-sized Microraptor up to the whale-sized Giganotosaurus, in the face of intense competition and the demands of ontogenetic growth. Facultative scavenging, a behavior present in almost all modern predators, may have been important in supplementing energetically expensive lifestyles. By using agentbased models based on the allometric relationship between size and foraging behaviors, we show that theropods between 27 and 1,044 kg would have gained a significant energetic advantage over individuals at both the small and large extremes of theropod body mass through their scavenging efficiency. These results were robust to rate of competition, primary productivity, and detection distance. Our models demonstrate the potential importance of facultative scavenging in theropods and the role of body size in defining its prevalence in Mesozoic terrestrial systems.Publisher PDFPeer reviewe

Survival and population dynamics of the Marabou Stork in an isolated population, Swaziland

Investigating the ecology of long lived birds is particularly challenging owing to the time scales involved. Here an analysis is presented of a long term study of the survival and population dynamics of the marabou stork (Leptoptilos crumeniferus), a wide ranging scavenging bird from Sub-Saharan Africa. Using resightings data of tagged nestlings and free flying birds we show that the stork population can be divided into three general life stages with unique survival probabilities and fecundities. Fecundity of the storks is inversely related to rainfall during their breeding season. Corroborative evidence for a metapopulation structure is discussed highlighting the impact of the Swaziland birds on the ecology of the species in the broader region. The importance of tag loss or illegibility over time is highlighted. Clearly, any attempt at conserving a species will require a detailed understanding of its population structure, of the sort examined here

Evolution of the eastward shift in the quasi-stationary minimum of the Antarctic total ozone column

The quasi-stationary pattern of the Antarctic total ozone has changed during the last 4 decades, showing an eastward shift in the zonal ozone minimum. In this work, the association between the longitudinal shift of the zonal ozone minimum and changes in meteorological fields in austral spring (September–November) for 1979–2014 is analyzed using ERA-Interim and NCEP–NCAR reanalyses. Regressive, correlative and anomaly composite analyses are applied to reanalysis data. Patterns of the Southern Annular Mode and quasi-stationary zonal waves 1 and 3 in the meteorological fields show relationships with interannual variability in the longitude of the zonal ozone minimum. On decadal timescales, consistent longitudinal shifts of the zonal ozone minimum and zonal wave 3 pattern in the middle-troposphere temperature at the southern midlatitudes are shown. Attribution runs of the chemistry–climate version of the Australian Community Climate and Earth System Simulator (ACCESS-CCM) model suggest that long-term shifts of the zonal ozone minimum are separately contributed by changes in ozone-depleting substances and greenhouse gases. As is known, Antarctic ozone depletion in spring is strongly projected on the Southern Annular Mode in summer and impacts summertime surface climate across the Southern Hemisphere. The results of this study suggest that changes in zonal ozone asymmetry accompanying ozone depletion could be associated with regional climate changes in the Southern Hemisphere in spring

Metadata Deep Dive: Results from a Detailed Quality Assessment of NASA's Earth Observation Metadata

No abstract availabl

Can patients independently identify their urinary incontinence symptoms?

INTRODUCTION AND HYPOTHESIS: The objective of our study is to compare patient self-reported urinary incontinence symptoms based on the International Consultation on Incontinence Questionnaire- Short Form (ICIQ-SF) question number 6 (When does urine leak?) with physician-assessed interpretation of the patient\u27s urinary incontinence symptoms. METHODS: This trial is a cross-sectional study of patients who presented to a tertiary urogynecology center with symptoms of urinary incontinence between January 2014 and August 2016. We compared patient-reported symptoms on the ICIQ-SF with physician interpretation of urinary complaints during their initial visit. The urinary incontinence symptoms included stress urinary incontinence (SUI), urgency urinary incontinence (UUI), insensible urine loss, nocturnal enuresis, and post-micturition dribbling. RESULTS: A total of 432 patients with a mean age of 61 were included in this evaluation. The most common urinary incontinence symptoms according to the physician were UUI (n = 357, 83%), followed by SUI (n = 308, 71%). Of the patients who were diagnosed by a physician with the symptom of UUI, only 61% self-identified as having this symptom based on the ICIQ-SF, and for SUI, only 66% self-identified as having SUI symptoms based on the ICIQ-SF. Overall UUI (κ = 0.30) appears to have poor agreement, as does nocturnal enuresis (κ = 0.39), when compared with physician historical assessment. CONCLUSION: There is a discrepancy between patient-reported urinary incontinence symptoms on the ICIQ-SF and physician-assessed symptoms. Symptomatology entered into electronic medical records by patients is often inaccurate. Physician validation is essential in understanding the underlying the precise symptomatology