Tall trees are key drivers of ecosystem processes in tropical forest, but the controls on the distribution of the very tallest trees remain poorly understood. The recent discovery of grove of giant ...trees over 80 meters tall in the Amazon forest requires a reevaluation of current thinking. We used high‐resolution airborne laser surveys to measure canopy height across 282,750 ha of old‐growth and second‐growth forests randomly sampling the entire Brazilian Amazon. We investigated how resources and disturbances shape the maximum height distribution across the Brazilian Amazon through the relations between the occurrence of giant trees and environmental factors. Common drivers of height development are fundamentally different from those influencing the occurrence of giant trees. We found that changes in wind and light availability drive giant tree distribution as much as precipitation and temperature, together shaping the forest structure of the Brazilian Amazon. The location of giant trees should be carefully considered by policymakers when identifying important hot spots for the conservation of biodiversity in the Amazon.
Common drivers of height development are fundamentally different from those influencing the occurrence of giant trees. While maximum tree height across the Brazilian Amazon was related to a large number of environmental variables, changes in wind and light availability drive giant tree distribution.
•Finite difference methods for arbitrary domain are almost second-order.•Non-body conformal Cartesian grids almost use linear or quadratic interpolations.•A 6th-order of approximations on curved ...boundary domain is achieved.•A simple list of border points together with the BC is required.•General Robin conditions are treated in a general framework.
An arbitrary order finite difference method for curved boundary domains with Cartesian grid is proposed. The technique handles in a universal manner Dirichlet, Neumann or Robin conditions. We introduce the Reconstruction Off-site Data (ROD) method, that transfers in polynomial functions the information located on the physical boundary to the computational domain. Three major advantages are: (1) a simple description of the physical boundary with Robin condition using a collection of points; (2) no analytical expression (implicit or explicit) is required, particularly the ghost cell centroids projection are not needed; (3) we split up into two independent machineries the boundary treatment and the resolution of the interior problem, coupled by the ghost cell values. Numerical evidences based on the simple 2D convection-diffusion operators are presented to prove the capability of the method to reach at least the 6th-order with arbitrary smooth domains.
Summary
Evidence suggests that creatine may have some beneficial effects on bone. The study aimed to investigate the effects of exercise alone or combined with creatine on bone health in ...ovariectomized rats. Findings show that exercise, but not creatine, has an important role in improving bone health.
Introduction
The aim of this study was to investigate the effects of exercise training alone or combined with creatine supplementation on bone health parameters in ovariectomized rats.
Methods
Wistar rats were randomly allocated into one of five groups: (i) sham-operated, (ii) ovariectomized non-trained placebo-supplemented, (iii) ovariectomized non-trained creatine-supplemented, (iv) ovariectomized exercise-trained placebo-supplemented, and (v) ovariectomized exercise-trained creatine-supplemented. Downhill running training and/or creatine supplementation (300 mg/kg body weight) were administered for 12 weeks. Bone mineral content (BMC), bone mineral density (BMD), and biomechanical and histomorphometric parameters were assessed.
Results
No interaction effects were observed for BMC and BMD at whole body, femur, and lumbar spine (
p
> 0.05). Importantly, a main effect of training was detected for whole body BMC and BMD (
p
= 0.003 and
p
< 0.001, respectively), femoral BMC and BMD (
p
= 0.005 and
p
< 0.001, respectively), and lumbar spine BMC and BMD (
p
< 0.001 and
p
< 0.001, respectively), suggesting that the trained animals had higher bone mass, irrespective of creatine supplementation. Main effects of training were also observed for maximal load (
p
< 0.001), stiffness (
p
< 0.001), and toughness (
p
= 0.046), indicating beneficial effects of exercise training on bone strength. Neither a main effect of supplementation nor an interaction effect was detected for biomechanical parameters (
p
> 0.05). No main or interaction effects were observed for any of the histomorphometric parameters evaluated (
p
> 0.05).
Conclusions
Exercise training, but not creatine supplementation, attenuated ovariectomy-induced bone loss in this rat model.
Securing economically and ecologically significant molluscs, as our oceans warm due to climate change, is a global priority. South eastern Australia receives warm water in a strengthening East ...Australia Current and so resident species are vulnerable to elevated temperature and marine heat waves. This study tested whether prior exposure to elevated temperature can enhance resilience of oysters to ocean warming. Two Australian species, the flat oyster, Ostrea angasi, and the Sydney rock oyster, Saccostrea glomerata, were obtained as adults and "heat shocked" by exposure to a dose of warm water in the laboratory. Oysters were then transferred to elevated seawater temperature conditions where the thermal outfall from power generation was used as a proxy to investigate the impacts of ocean warming. Shell growth, condition index, lipid content and survival of flat oysters and condition of Sydney rock oysters were all significantly reduced by elevated seawater temperature in the field. Flat oysters grew faster than Sydney rock oysters at ambient temperature, but their growth and survival was more sensitive to elevated temperature. "Stress inoculation" by heat shock did little to ameliorate the negative effects of increased temperature, although the survival of heat-shocked flat oysters was greater than non-heat shocked oysters. Further investigations are required to determine if early exposure to heat stress can enhance resilience of oysters to ocean warming.
Dairy cows experiencing heat stress have reduced intake and increased reliance on glucose, making feeding strategies capable of improving diet digestibility plausible for improving postrumen nutrient ...flow and performance. The effect of yeast on digestion and performance of lactating cows during the warm summer months of southeastern Brazil was evaluated. Cows were individually fed in tie stalls and temperature-humidity index was above 68 during 75.6% of the experiment. Twenty-eight Holstein cows (207±87 d in milk) received a standard diet for 14 d and then a treatment for 70 d, in a covariate-adjusted, randomized block design with repeated measures over time. Treatments were yeast (Saccharomyces cerevisiae) or control. Yeast was top dressed to the diet in the morning, equivalent to 25×1010 cfu of live cells and 5×1010 cfu of dead cells. The diet contained corn silage (37.7%), Tifton silage (7.1%), raw soybeans (4.1%), soybean meal (16.5%), finely ground corn (20.7%), and citrus pulp (11.9%). Yeast increased milk (26.7 vs. 25.4kg/d) and solids yield (3.06 vs. 2.92kg/d), especially lactose. Response in milk yield was consistent over time and started at d 5. The daily intake of digestible OM, total-tract digestibility of nutrients, urinary allantoin excretion, chewing pattern throughout the day, and dry matter intake did not respond to yeast. A trend was observed for increased plasma glucose with yeast (62.9 vs. 57.3mg/dL), lowered respiratory frequency (48 vs. 56 breaths/min), and increased plasma niacin content (1.31 vs. 1.22 µg/mL), though cows had similar rectal temperature. Ruminal lactate and butyrate as proportions of ruminal organic acids were reduced by yeast, but no effects on other organic acids, ruminal pH, or protozoa content were detected. Plasma urea N over 24h was increased by yeast. On d 72 to 74, citrus pulp was abruptly replaced with finely ground corn to induce acidosis. The increased load of starch increased dry matter intake between 0700 and 1300h, jugular blood partial pressure of CO2, HCO3−, and base excess, and decreased blood pH for both treatments. The yeast treatment had a higher blood pH compared with the control, 7.34, and 7.31, respectively. Yeast supplementation improved lactation performance of dairy cows under heat stress. Improvement in lactation performance apparently involved the regulation of body homeothermia, rather than improved digestibility.
Cancer patients with lymph node (LN) metastases have a worse prognosis than those without nodal disease. However, why LN metastases correlate with reduced patient survival is poorly understood. ...Recent findings provide insight into mechanisms underlying tumor growth in LNs. Tumor cells and their secreted molecules engage stromal, myeloid, and lymphoid cells within primary tumors and in the lymphatic system, decreasing antitumor immunity and promoting tumor growth. Understanding the mechanisms of cancer survival and growth in LNs is key to designing effective therapy for the eradication of LN metastases. In addition, uncovering the implications of LN metastasis for systemic tumor burden will inform treatment decisions. In this review, we discuss the current knowledge of the seeding, growth, and further dissemination of LN metastases.
Highlights • To develop a new dataset based on handwritten exams to aid Parkinson's Disease diagnosis; • To propose a new approach to extract features from those exams based on image processing; • To ...evaluate the features extracted from the dataset over two different drawings: spirals and meanders; • To make available the dataset to the scientific community.
Summary
In this randomized double-blind placebo-controlled 24-week trial, cholecalciferol supplementation at 50,000 IU/week effectively improved bone microarchitecture parameters in juvenile-onset ...systemic lupus erythematosus (JoSLE) patients, as assessed by high-resolution peripheral quantitative computed tomography (HR-pQCT) at tibia site. An increase in the trabecular number and a decrease in the trabecular separation were observed, suggesting that vitamin D supplementation may be recommended for JoSLE patients with its deficiency.
Introduction
Vitamin D has an important effect on bone but there are no trials that directly address the boosting of serum levels of 25-hydroxyvitamin D (25OHD) in bone microarchitecture in JoSLE patients. The aim of this study was to evaluate the effect of vitamin D supplementation on bone microarchitecture parameters using HR-pQCT in JoSLE patients.
Methods
This study was a randomized double-blind placebo-controlled 24-week trial. Forty female JoSLE patients were randomized (1:1) to receive oral cholecalciferol at 50,000 IU/week (JoSLE-VitD) or placebo (JoSLE-PL). The medications remained stable throughout the study. Serum levels of 25OHD were measured using a radioimmunoassay. The bone microarchitecture and volumetric bone density were analyzed using HR-pQCT at tibia site.
Results
At baseline, the groups were similar with respect to their age, body mass index, organ involvement, glucocorticoid dose, immunosuppressant use, serum 25OHD levels, and HR-pQCT parameters. After 24 weeks, higher 25OHD levels were observed in the JoSLE-VitD group compared to the JoSLE-PL group 31.3 (8.6) vs. 16.5 (5.8) ng/mL,
p
< 0.001. An increase in the trabecular number ∆Tb.
N
0.16 (0.24) vs. 0.03 (0.19) 1/mm,
p
= 0.024 and a decrease in the trabecular separation ∆ThSp −0.045 (0.067) vs. 0.001 (0.009) mm,
p
= 0.017 were found in the JoSLE-VitD group compared to the JoSLE-PL group at tibia site. No differences were observed in other structural parameters trabecular (Tb.Th) or cortical thickness (Ct.Th), volumetric bone mineral densities, cortical porosity, and biomechanical parameters (
p
> 0.05).
Conclusion
This study suggests that cholecalciferol supplementation for 24 weeks effectively improved the bone microarchitecture parameters, mainly the trabecular number, in JoSLE patients.
Trial Registration
NCT01892748
The ocean has been assumed as the main sink of microplastics (MPs), however, soils may also receive MPs from different sources and through different pathways, which may affect the biota and their ...role in soil functions. To the best of our knowledge, only one study, until now, reported the effects of MPs on the survival and fitness of soil organisms (Lumbricus terrestris). In our study, epigeic earthworms, of the species E. andrei, were exposed to different concentrations of MPs (0, 62.5, 125, 250, 500 and 1000 mg/kg soildw) in an OECD artificial soil and tested for reproduction, survival and growth of adults, following a standard protocol. The size of the polyethylene MPs to which earthworms were exposed ranged between 250 and 1000 μm. No significant effects were recorded on survival, number of juveniles and, in the final weight of adult earthworms after 28d of exposure, to the different concentrations of MPs. Nevertheless, FTIR-ATR of earthworms and histopathological analysis of the gut provided evidences of damages and immune system responses to MPs.
Display omitted
•Earthworms may be able to selectively ingest microplastics and/or to egest them.•Serious histological damages in the gut of earthworms were observed.•Molecular changes in the body of earthworms point for possible immune system responses.•Hystopathopatological analyses also showed serious signs of gut inflammation.•Immune system responses seemed to be related with those to deal with strange bodies.
This is one of the first studies assessing the effects of microplastics on terrestrial earthworms and it provides evidence of tissue damage in the gut and immune system responses.
This paper presents a methodology for automated disturbance analysis and fault location on electric power distribution systems using a combination of modern techniques for network analysis, signal ...processing, and intelligent systems. New algorithms to detect, classify, and locate power-quality disturbances are developed. The continuous process of detecting these disturbances is accomplished through statistical analysis and multilevel signal analysis in the wavelet domain. The behavioral indices of the current and voltage signals are extracted by employing the discrete wavelet transform, multiresolution analysis, and the concept of signal energy. These indices are used by a number of independent Fuzzy-ARTMAP neural networks, which aim to classify the fault type and the power-quality events. The fault location is performed after the classification process. A real life three-phase distribution system with 134 nodes-13.8 kV and 7.065 MVA-was used to test the proposed algorithms, providing satisfactory results, attesting that the proposed algorithms are efficient, fast, and, above all, intelligent.
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