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First-year effects of broadcast burning on soil infiltration and wettability in southwest Oregon
Soil infiltration and wettability measurements during the first year following a broadcast burn in the Siskiyou Mountains of
southwest Oregon, have illustrated the magnitude of the effects of light-to-moderate intensity burning on hydrological soil
properties. A prescribed fire near White Creek in late spring significantly reduced soil infiltration for 4 months following the
burn, but infiltration rates below the maximum 100 year precipitation event for the area were not observed. The lowest infiltration rate recorded on logged and burned soil was 5.3 cm/hr (2.1 in/hr), but 94% of all the observations ranged between 9.0 and 11.4 cm/hr (3.5 and 4.5 in/hr). Infiltration rates recorded on logged and unburned soil were greater than 11.2 cm/hr.
Broadcast burning caused hydrophobic substances in the litter and duff layers to become volatilized, subsequent condensation of these substances on soil particles located in the 0-5cm depth of soil. A total of 25% of the exposed mineral soil surface in the
burned section was water repellent 9 days after burning, but this was reduced to 6% within five months. Some naturally-occurring water repellency existed in the unburned condition, yet the greatest percentage recorded was only 1% in August, when soils were at their driest. In assessing the wetting difficulties of a soil sample, the
measurement of an apparent liquid-solid contact angle was more consistent than obtaining water drop penetration times. The
penetration time of a water drop is dependent on the wetting difficulties and pore geometry of the soil directly beneath it, therefore measurements were highly variable for any one soil sample. Regression models correlated infiltration rates with soil contact angles in the burned section. Association was strongest (r² = .93) for infiltration rates obtained on unsaturated soils in which
attraction forces between the soil particles and water molecules predominate. Since this attraction is inversely related to the
liquid-solid contact angle, infiltration rates decreased with increases in the liquid-solid contact angle. During the summer, residual vegetation in the unburned section significantly reduced percent soil moisture below levels recorded in the burned condition. Increased precipitation and lower
evapotranspiration demands, combined with rapid growth of resprouting and invading vegetation in the burned section during early fall, probably led to soil moisture becoming nearly equal in both conditions by mid-fall.
Supplemental hydrological soil measurements, collected 33 days after a moderate intensity broadcast burn at Shan Creek, did not
markedly differ from those obtained 44 days after the light-to-moderate intensity burn at White creek. Although Shan Creek did have
a greater percentage of water repellent soil (52% vs. 12%), there was not a significant difference between infiltration rates obtained at both sites
A Cross-National Investigation of Hallucination-Like Experiences in 10 Countries: The E-CLECTIC Study
Hallucination-like experiences (HLEs) are typically defined as sensory perceptions in the absence of external stimuli. Multidimensional tools, able to assess different facets of HLEs, are helpful for a better characterization of hallucination proneness and to investigate the cross-national variation in the frequencies of HLEs. The current study set out to establish the validity, factor structure, and measurement invariance of the Launay-Slade Hallucinations Scale-Extended (LSHS-E), a tool to assess HLEs. A total of 4419 respondents from 10 countries were enrolled. Network analyses between the LSHS-E and the 3 dimensions of the Community Assessment of Psychic Experiences (CAPE) were performed to assess convergent and divergent validity of the LSHS-E. Confirmatory factor analysis was used to test its measurement invariance. The best fit was a 4-factor model, which proved invariant by country and clinical status, indicating cross-national stability of the hallucination-proneness construct. Among the different components of hallucination-proneness, auditory-visual HLEs had the strongest association with the positive dimension of the CAPE, compared with the depression and negative dimensions. Participants who reported a diagnosis of a mental disorder scored higher on the 4 LSHS-E factors. Small effect size differences by country were found in the scores of the 4 LSHS-E factors even after taking into account the role of socio-demographic and clinical variables. Due to its good psychometric properties, the LSHS-E is a strong candidate tool for large investigations of HLEs
Possible disease-modifying factors: the mannan-binding lectin pathway and infections in hereditary angioedema of children and adults
Belief Revision and Delusions: How Do Patients with Schizophrenia Take Advice?
The dominant cognitive model that accounts for the persistence of delusional beliefs in schizophrenia postulates that patients suffer from a general deficit in belief revision. It is generally assumed that this deficit is a consequence of impaired reasoning skills. However, the possibility that such inflexibility affects the entire system of a patient's beliefs has rarely been empirically tested. Using delusion-neutral material in a well-documented advice-taking task, the present study reports that patients with schizophrenia: 1) revise their beliefs, 2) take into account socially provided information to do so, 3) are not overconfident about their judgments, and 4) show less egocentric advice-discounting than controls. This study thus shows that delusional patients' difficulty in revising beliefs is more selective than had been previously assumed. The specificities of the task and the implications for a theory of delusion formation are discussed
Study protocol: a double blind randomised control trial of high volume image guided injections in Achilles and patellar tendinopathy in a young active population
Design concepts for the Cherenkov Telescope Array CTA: an advanced facility for ground-based high-energy gamma-ray astronomy
Ground-based gamma-ray astronomy has had a major breakthrough with the impressive results obtained using systems of imaging atmospheric Cherenkov telescopes. Ground-based gamma-ray astronomy has a huge potential in astrophysics, particle physics and cosmology. CTA is an international initiative to build the next generation instrument, with a factor of 5-10 improvement in sensitivity in the 100 GeV-10 TeV range and the extension to energies well below 100 GeV and above 100 TeV. CTA will consist of two arrays (one in the north, one in the south) for full sky coverage and will be operated as open observatory. The design of CTA is based on currently available technology. This document reports on the status and presents the major design concepts of CTA
Evidence for Sub-Haplogroup H5 of Mitochondrial DNA as a Risk Factor for Late Onset Alzheimer's Disease
BACKGROUND: Alzheimer's Disease (AD) is the most common neurodegenerative disease and the leading cause of dementia among senile subjects. It has been proposed that AD can be caused by defects in mitochondrial oxidative phosphorylation. Given the fundamental contribution of the mitochondrial genome (mtDNA) for the respiratory chain, there have been a number of studies investigating the association between mtDNA inherited variants and multifactorial diseases, however no general consensus has been reached yet on the correlation between mtDNA haplogroups and AD. METHODOLOGY/PRINCIPAL FINDINGS: We applied for the first time a high resolution analysis (sequencing of displacement loop and restriction analysis of specific markers in the coding region of mtDNA) to investigate the possible association between mtDNA-inherited sequence variation and AD in 936 AD patients and 776 cognitively assessed normal controls from central and northern Italy. Among over 40 mtDNA sub-haplogroups analysed, we found that sub-haplogroup H5 is a risk factor for AD (OR=1.85, 95% CI:1.04-3.23) in particular for females (OR=2.19, 95% CI:1.06-4.51) and independently from the APOE genotype. Multivariate logistic regression revealed an interaction between H5 and age. When the whole sample is considered, the H5a subgroup of molecules, harboring the 4336 transition in the tRNAGln gene, already associated to AD in early studies, was about threefold more represented in AD patients than in controls (2.0% vs 0.8%; p=0.031), and it might account for the increased frequency of H5 in AD patients (4.2% vs 2.3%). The complete re-sequencing of the 56 mtDNAs belonging to H5 revealed that AD patients showed a trend towards a higher number (p=0.052) of sporadic mutations in tRNA and rRNA genes when compared with controls. CONCLUSIONS: Our results indicate that high resolution analysis of inherited mtDNA sequence variation can help in identifying both ancient polymorphisms defining sub-haplogroups and the accumulation of sporadic mutations associated with complex traits such as AD
Mitochondrial superclusters influence age of onset of Parkinson’s disease in a gender specific manner in the Cypriot population: A case-control study
Despite evidence supporting an involvement of mitochondrial dysfunction in the pathogenesis of some neurodegenerative disorders, there are inconsistent findings concerning mitochondrial haplogroups and their association to neurodegenerative disorders, including idiopathic Parkinson's disease (PD).To test this hypothesis for the Greek-Cypriot population, a cohort of 230 PD patients and 457 healthy matched controls were recruited. Mitochondrial haplogroup distributions for cases and controls were determined. Association tests were carried out between mitochondrial haplogroups and PD.Mitochondrial haplogroup U was associated with a reduced PD risk in the Cypriot population. After pooling mitochondrial haplogroups together into haplogroup clusters and superclusters, association tests demonstrated a significantly protective effect of mitochondrial haplogroup cluster N (xR) and supercluster LMN for PD risk only in females. In addition, for female PD cases belonging to UKJT and R (xH, xUKJT) haplogroup, the odds of having a later age of onset of PD were 13 and 15 times respectively higher than the odds for female cases with an H haplogroup.Statistically significant associations regarding PD risk and PD age of onset were mostly detected for females thus suggesting that gender is a risk modifier between mitochondrial haplogroups and PD status / PD age of onset. The biological mechanisms behind this gender specificity remain to be determined
Wplyw nawozenia fosforowego na zawartosc olowiu w rzodkiewce [Raphanus sativus L.subvar.radicula pers.] i szpinaku [Spinacia oleracea L.]
Przeprowadzono doświadczenie wazonowe w celu zbadania wpływu nawożenia fosforowego na kumulację ołowiu przez rzodkiewkę i szpinak. Przyjęto trzy stopnie nawożenia fosforowego: 50, 200, 800 mg P/kg s.m. podłoża i trzy dawki ołowiu 0, 275 i 550 mg/kg s.m. Dwie odmiany rzodkiewki Saxa i Rowa oraz dwie odmiany szpinaku Matador i Asta F₁ zebrano w fazie dojrzałości zbiorczej i oznaczono zawartość ołowiu w zgrubieniach i liściach rzodkiewki i liściach szpinaku. Wykonano też analizy składu mineralnego oraz suchej masy i wybranych związków organicznych w częściach jadalnych obu warzyw. Podniesienie poziomu fosforu w glebie z 50 do 800 mg/kg s.m. spowodowało spadek ilości zgromadzonego Pb w zgrubieniach rzodkiewki o około 30 % (bez różnic odmianowych), w liściach szpinaku redukcja osiągnęła 75 % u odmiany Asta. Na podłożach intensywniej nawożonych stwierdzono również ograniczenie translokacji ołowiu ze zgrubień do części nadziemnych rzodkiewki. Nie stwierdzono żadnych zmian w morfologii badanych warzyw, skumulowany ołów wpłynął natomiast na ich wartość biologiczną. W materiale z podłoża o najniższej zawartości fosforanów wystąpiły spadki P, Mn i barwników u obu testowanych gatunków. W zgrubieniach rzodkiewki obniżył się także poziom Zn, suchej masy, cukrów rozpuszczalnych i kwasu askorbinowgo, a w liściach szpinaku Cu i białka ogólnego - wzrosła natomiast ilość suchej masy i cukrów. Intensyfikacja nawożenia fosforowego spowodowała ograniczenie skali tych zmian, nie pozwoliła jednak na całkowitą ich eliminację.Pot experiments concerned the effect of phosphates in soil on the accumulation of lead by radish and spinach. Three levels of phosphate fertilising were applied: 50, 200, 800 mg P/kg d.w. and three doses of lead: 0, 275 and 550 mg/kg d.w. of substrate. Saxa and Rowa radishes and Matador and Asta F₁ spinach cultivars were harvested at the stage of harvest maturity; the content of lead and selected mineral and organic components being determined in edible parts of vegetables. An increase in phosphorus content in soil caused a significant decrease in Pb absorbed by radish roots to about 30 % (without differences for cultivars). The stronger effect was obtained for spinach - the drops of this metal amounted to 75 %, the cultivar differences also appeared. Accumulated lead significantly modified biological value of plants collected from the soil with content 50 mg P/kg d.w. The increase in the level of phosphates in substrates pennitted to limit these changes considerably
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