571 research outputs found
Ecological Site Database- Basic Site Information for Resource Analysis and Decision Making
The USDA Natural Resource Conservation Service (NRCS) describes and interprets range, native pasture, grazable forest, pasture, and hayland with ecological site descriptions and forage suitability groups. Ecological sites have evolved from agency range and woodland site descriptions, and have integrated alternate and more recent concepts with the traditional succession-retrogression model for site classification and interpretation. Ecological site interpretations are based on vegetation sampling by weight and composition, and other field data collection. Sample data is recorded and managed in the Ecological Site Information System (ESIS) and is analyzed to identify and develop site and suitability group descriptions. ESIS provides data that facilitates resource inventory, analysis, and planning using the agency field office computing system (FOCS), in particular, grazing land decision support software (GLA)
Seed priming enhances early growth and improves area of soil exploration by roots
Introduction: Seed priming has been conducted for centuries with growth advantages reported for a variety of different crops. Previous work has suggested priming does not offer a yield advantage despite an increased early growth if grown under ideal conditions. However, how these advantages unfold in regards to early root development is largely unknown.Results: We observed accelerated germination speed in primed seeds regardless of applied seed enhancement technology i.e. coating or pelleting. Additionally, we found significant differences in lateral root development in primed seeds vs non-primed seeds. Furthermore, we recorded an increase in volume and surface of embryo and perisperm indicating a distinct morphological change during the germination process of primed seeds compared to non-primed seeds.Conclusions: We attribute the enhanced early plant development in primed seeds to increased root development and thus enhanced volume of the soil resource mined for nutrients. This improvement can be detected four days after emergence within the root system throughout the early plant development despite an early transition from seed reserves to soil based growth. The understanding of below ground root architecture characteristics can improve the selection of appropriate seed enhancement technologies and seedbed management practices
Decreased symptoms of depression after mindfulness-based stress reduction: potential moderating effects of religiosity, spirituality, trait mindfulness, sex, and age
Objective: mindfulness-based stress reduction (MBSR) is a secular meditation training program that reduces depressive symptoms. Little is known, however, about the degree to which a participant's spiritual and religious background, or other demographic characteristics associated with risk for depression, may affect the effectiveness of MBSR. Therefore, this study tested whether individual differences in religiosity, spirituality, motivation for spiritual growth, trait mindfulness, sex, and age affect MBSR effectiveness.Methods: as part of an open trial, multiple regression was used to analyze variation in depressive symptom outcomes among 322 adults who enrolled in an 8-week, community-based MBSR program.Results: as hypothesized, depressive symptom severity decreased significantly in the full study sample (d=0.57; p<0.01). After adjustment for baseline symptom severity, moderation analyses revealed no significant differences in the change in depressive symptoms following MBSR as a function of spirituality, religiosity, trait mindfulness, or demographic variables. Paired t tests found consistent, statistically significant (p<0.01) reductions in depressive symptoms across all subgroups by religious affiliation, intention for spiritual growth, sex, and baseline symptom severity. After adjustment for baseline symptom scores, age, sex, and religious affiliation, a significant proportion of variance in post-MBSR depressive symptoms was uniquely explained by changes in both spirituality (?=?0.15; p=0.006) and mindfulness (?=?0.17; p<0.001).Conclusions: these findings suggest that MBSR, a secular meditation training program, is associated with improved depressive symptoms regardless of affiliation with a religion, sense of spirituality, trait level of mindfulness before MBSR training, sex, or age. Increases in both mindfulness and daily spiritual experiences uniquely explained improvement in depressive symptom
Association of Early Beta-amyloid Accumulation and Neuroinflammation Measured with [11C]PBR28 in Elderly Individuals Without Dementia
OBJECTIVE: To examine whether early β-amyloid (Aβ) accumulation and metabolic risk factors are associated with neuroinflammation in elderly individuals without dementia. METHODS: We examined 54 volunteers (mean age 70.0, 56% women, 51% APOE ε4 carriers) with a TSPO-tracer [11C]PBR28 to assess neuroinflammation and with [11C]Pittsburgh compound B (PiB) to assess cerebral Aβ accumulation. [11C]PBR28 and [11C]PiB standardized uptake value ratios (SUVRs) were quantified in six regions of interests by using the cerebellar cortex as a pseudo-reference/reference region, respectively. Fasting venous glucose, insulin, and high sensitivity C-reactive protein (hs-CRP) values were determined. Homeostatic model assessment of insulin resistance (HOMA-IR) was calculated. A subset of individuals (n=11) underwent CSF sampling, and Aβ40, Aβ42, total-tau, phospho-tau, soluble TREM2 and YKL-40 levels were measured. RESULTS: Among the whole study group, no significant association was found between [11C]PiB and [11C]PBR28 SUVR composite scores (slope 0.02, p=0.30). However, higher [11C]PiB binding was associated with higher [11C]PBR28 binding among amyloid negative ([11C]PiB composite score ≤1.5) (TSPO-genotype, age and sex adjusted slope 0.26, p=0.008) but not among amyloid positive participants (slope: -0.004, p=0.88). Higher CSF sTREM2 (rs 0.72, p=0.01) and YKL-40 (rs=0.63, p=0.04) concentrations were associated with a higher [11C]PBR28 composite score. Higher body mass index, HOMA-IR, and hs-CRP were associated with higher [11C]PBR28 binding in brain regions where Aβ accumulation is first detected in Alzheimer's disease (AD). CONCLUSIONS: While there was no association between amyloid and neuroinflammation in the overall study group, neuroinflammation was associated with amyloid among the subgroup at early stages of amyloid pathology
Phosphorus regulates ectomycorrhizal fungi biomass production in a Norway spruce forest
Ectomycorrhizal fungi (EMF) are important components of soil microbial communities, and EMF biomass can potentially increase carbon (C)
stocks by accumulating in the soils as necromass and producing recalcitrant structures. EMF growth depends on the C allocated belowground by
the host trees, and the nutrient limitation on tree growth is expected to influence this allocation. Therefore, studying EMF production and
understanding the factors that regulates it in natural soils are important to understand C cycling in forests.
Fungal mycelium collected from ingrowth mesh bags is commonly used to estimate EMF biomass, but these measurements might not reflect the total
EMF production since turnover rates of the hyphae are not considered. Here we estimated EMF production and turnover in response to
P fertilization (applied as superphosphate) in a Norway spruce forest where nitrogen (N) deposition has resulted in
phosphorus (P) limitation of plant production by using a combination of mesh bags with different incubation periods and with Bayesian
inferences. To test how localized patches of N and P influence EMF production and turnover we amended some bags with a nitrogen source
(methylene urea) or P source (apatite). Additionally, the Bayesian model tested the effect of seasonality (time of mesh-bag harvesting) on
EMF production and turnover.
We found that turnover of EMF was not affected by P fertilization or mesh-bag amendment. P fertilization had a negative effect on
EMF production in all the mesh-bag amendments, suggesting a reduced belowground C allocation to the EMF when P limitation is
alleviated. Apatite amendment significantly increased EMF biomass production in comparison with the pure quartz bags in the control plots but not in
the P-fertilized plots. This indicates that P-rich patches enhance EMF production in P-limited forests, but not when P
is not limiting. Urea amendment had a generally positive effect on EMF production, but this was significantly reduced by P fertilization,
suggesting that a decrease in EMF production due to the alleviated P limitation will affect N foraging. Seasonality had a significant
effect on EMF production, and the differences registered between the treatments were higher during the warmer months and disappeared at the end of
the growing season.
Many studies highlight the importance of N for regulating belowground C allocation to EMF in northern coniferous forests, but here we
show that the P status of the forest can be equally important for belowground carbon allocation to EMF production in areas with high
N deposition.</p
Effect of moisture on leaf litter decomposition and its contribution to soil respiration in a temperate forest
The degree to which increased soil respiration rates following wetting is caused by plant (autotrophic) versus microbial (heterotrophic) processes, is still largely uninvestigated. Incubation studies suggest microbial processes play a role but it remains unclear whether there is a stimulation of the microbial population as a whole or an increase in the importance of specific substrates that become available with wetting of the soil. We took advantage of an ongoing manipulation of leaf litter <sup>14</sup>C contents at the Oak Ridge Reservation, Oak Ridge, Tennessee, to (1) determine the degree to which an increase in soil respiration rates that accompanied wetting of litter and soil, following a short period of drought, could be explained by heterotrophic contributions; and (2) investigate the potential causes of increased heterotrophic respiration in incubated litter and 0–5 cm mineral soil. The contribution of leaf litter decomposition increased from 6 ± 3 mg C m<sup>−2</sup> hr<sup>−1</sup> during a transient drought, to 63 ± 18 mg C m<sup>−2</sup> hr<sup>−1</sup> immediately after water addition, corresponding to an increase in the contribution to soil respiration from 5 ± 2% to 37 ± 8%. The increased relative contribution was sufficient to explain all of the observed increase in soil respiration for this one wetting event in the late growing season. Temperature (13°C versus 25°C) and moisture (dry versus field capacity) conditions did not change the relative contributions of different decomposition substrates in incubations, suggesting that more slowly cycling C has at least the same sensitivity to decomposition as faster cycling organic C at the temperature and moisture conditions studied
APOE ε4 gene dose effect on imaging and blood biomarkers of neuroinflammation and beta-amyloid in cognitively unimpaired elderly
BACKGROUND: Neuroinflammation, characterized by increased reactivity of microglia and astrocytes in the brain, is known to be present at various stages of the Alzheimer's disease (AD) continuum. However, its presence and relationship with amyloid pathology in cognitively normal at-risk individuals is less clear. Here, we used positron emission tomography (PET) and blood biomarker measurements to examine differences in neuroinflammation and beta-amyloid (Aβ) and their association in cognitively unimpaired homozygotes, heterozygotes, or non-carriers of the APOE ε4 allele, the strongest genetic risk for sporadic AD. METHODS: Sixty 60-75-year-old APOE ε4 homozygotes (n = 19), heterozygotes (n = 21), and non-carriers (n = 20) were recruited in collaboration with the local Auria biobank. The participants underwent 11C-PK11195 PET (targeting 18-kDa translocator protein, TSPO), 11C-PiB PET (targeting Aβ), brain MRI, and neuropsychological testing including a preclinical cognitive composite (APCC). 11C-PK11195 distribution volume ratios and 11C-PiB standardized uptake value ratios (SUVRs) were calculated for regions typical for early Aβ accumulation in AD. Blood samples were drawn for measuring plasma glial fibrillary acidic protein (GFAP) and plasma Aβ1-42/1.40. RESULTS: In our cognitively unimpaired sample, cortical 11C-PiB-binding increased according to APOE ε4 gene dose (median composite SUVR 1.47 (range 1.38-1.66) in non-carriers, 1.55 (1.43-2.02) in heterozygotes, and 2.13 (1.61-2.83) in homozygotes, P = 0.002). In contrast, cortical composite 11C-PK11195-binding did not differ between the APOE ε4 gene doses (P = 0.27) or between Aβ-positive and Aβ-negative individuals (P = 0.81) and associated with higher Aβ burden only in APOE ε4 homozygotes (Rho = 0.47, P = 0.043). Plasma GFAP concentration correlated with cortical 11C-PiB (Rho = 0.35, P = 0.040), but not 11C-PK11195-binding (Rho = 0.13, P = 0.47) in Aβ-positive individuals. In the total cognitively unimpaired population, both higher composite 11C-PK11195-binding and plasma GFAP were associated with lower hippocampal volume, whereas elevated 11C-PiB-binding was associated with lower APCC scores. CONCLUSIONS: Only Aβ burden measured by PET, but not markers of neuroinflammation, differed among cognitively unimpaired elderly with different APOE ε4 gene dose. However, APOE ε4 gene dose seemed to modulate the association between neuroinflammation and Aβ
Head-to-head comparison of plasma p-tau181, p-tau231 and glial fibrillary acidic protein in clinically unimpaired elderly with three levels of APOE4-related risk for Alzheimer's disease
Plasma phosphorylated tau (p-tau) and glial fibrillary acidic protein (GFAP) both reflect early changes in Alzheimer's disease (AD) pathology. Here, we compared the biomarker levels and their association with regional β-amyloid (Aβ) pathology and cognitive performance head-to-head in clinically unimpaired elderly (n = 88) at three levels of APOE4-related genetic risk for sporadic AD (APOE4/4 n = 19, APOE3/4 n = 32 or non-carriers n = 37). Concentrations of plasma p-tau181, p-tau231 and GFAP were measured using Single molecule array (Simoa), regional Aβ deposition with 11C-PiB positron emission tomography (PET), and cognitive performance with a preclinical composite. Significant differences in plasma p-tau181 and p-tau231, but not plasma GFAP concentrations were present between the APOE4 gene doses, explained solely by brain Aβ load. All plasma biomarkers correlated positively with Aβ PET in the total study population. This correlation was driven by APOE3/3 carriers for plasma p-tau markers and APOE4/4 carriers for plasma GFAP. Voxel-wise associations with amyloid-PET revealed different spatial patterns for plasma p-tau markers and plasma GFAP. Only higher plasma GFAP correlated with lower cognitive scores. Our observations suggest that plasma p-tau and plasma GFAP are both early AD markers reflecting different Aβ-related processes
Characterisation of CART-containing neurons and cells in the porcine pancreas, gastro-intestinal tract, adrenal and thyroid glands
<p>Abstract</p> <p>Background</p> <p>The peptide CART is widely expressed in central and peripheral neurons, as well as in endocrine cells. Known peripheral sites of expression include the gastrointestinal (GI) tract, the pancreas, and the adrenal glands. In rodent pancreas CART is expressed both in islet endocrine cells and in nerve fibers, some of which innervate the islets. Recent data show that CART is a regulator of islet hormone secretion, and that CART null mutant mice have islet dysfunction. CART also effects GI motility, mainly via central routes. In addition, CART participates in the regulation of the hypothalamus-pituitary-adrenal-axis. We investigated CART expression in porcine pancreas, GI-tract, adrenal glands, and thyroid gland using immunocytochemistry.</p> <p>Results</p> <p>CART immunoreactive (IR) nerve cell bodies and fibers were numerous in pancreatic and enteric ganglia. The majority of these were also VIP IR. The finding of intrinsic CART containing neurons indicates that pancreatic and GI CART IR nerve fibers have an intrinsic origin. No CART IR endocrine cells were detected in the pancreas or in the GI tract. The adrenal medulla harboured numerous CART IR endocrine cells, most of which were adrenaline producing. In addition CART IR fibers were frequently seen in the adrenal cortex and capsule. The capsule also contained CART IR nerve cell bodies. The majority of the adrenal CART IR neuronal elements were also VIP IR. CART IR was also seen in a substantial proportion of the C-cells in the thyroid gland. The majority of these cells were also somatostatin IR, and/or 5-HT IR, and/or VIP IR.</p> <p>Conclusion</p> <p>CART is a major neuropeptide in intrinsic neurons of the porcine GI-tract and pancreas, a major constituent of adrenaline producing adrenomedullary cells, and a novel peptide of the thyroid C-cells. CART is suggested to be a regulatory peptide in the porcine pancreas, GI-tract, adrenal gland and thyroid.</p
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