The analysis of gross primary production (GPP) is crucial to better understand CO2 exchanges between terrestrial ecosystems and the atmosphere, while the quantification of water-use efficiency (WUE) ...allows for the estimation of the compensation between carbon gained and water lost by the ecosystem. Understanding these dynamics is essential to better comprehend the responses of environments to ongoing climatic changes. The objective of the present study was to analyze, through AMERIFLUX and LBA network measurements, the variability of GPP and WUE in four distinct tropical biomes in Brazil: Pantanal, Amazonia, Caatinga and Cerrado (savanna). Furthermore, data measured by eddy covariance systems were used to assess remotely sensed GPP products (MOD17). We found a distinct seasonality of meteorological variables and energy fluxes with different latent heat controls regarding available energy in each site. Remotely sensed GPP was satisfactorily related with observed data, despite weak correlations in interannual estimates and consistent overestimations and underestimations during certain months. WUE was strongly dependent on water availability, with values of 0.95 gC kg−1 H2O (5.79 gC kg−1 H2O) in the wetter (drier) sites. These values reveal new thresholds that had not been previously reported in the literature. Our findings have crucial implications for ecosystem management and the design of climate policies regarding the conservation of tropical biomes, since WUE is expected to change in the ongoing climate change scenario that indicates an increase in frequency and severity of dry periods.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
The current study was undertaken to test the hypothesis that the high physical capacity of rowing athletes may not reverse the influence of age on cardiac autonomic control decline estimated by heart ...rate variability (HRV). Forty-four male subjects divided in four groups: 11 young athletes (YA; 18 ±1 year), 11 young non-athletes (YNA; 20 ±1 year), 11 middle age athletes (MAA; 43 ±6 years) and 11 middle age non-athletes (MNA; 44 ±8 years) participated in the study. Heart rate (HR) was recorded beat-by-beat for 10 minutes in supine (SUP) and 10 min in orthostatic (ORT) positions. HRV was analyzed in the frequency domain to obtain the spectral power in the high (HF) and low frequency (LF) bands, and the changes to ORT (%∆HRV) were calculated (ORT - SUP / SUP). During SUP, HF was lower in MNA and MA compared to YA and YNA, while LF was lower in MNA than YA. For %ΔHRV, %ΔHF was higher in YA than YNA, MA and MNA. The %ΔLF was not different among groups. In conclusion, aging seems to overcome the influence of physical fitness on neural regulation of the heart, as highlighted by the HRV response to active standing.
Abstract
A large proportion of the biodiversity of Amazonia, one of the most diverse rainforest areas in the world, is yet to be formally described. One such case is the Neotropical frog genus ...Adenomera. We here evaluate the species richness and historical biogeography of the Adenomera heyeri clade by integrating molecular phylogenetic and species delimitation analyses with morphological and acoustic data. Our results uncovered ten new candidate species with interfluve-associated distributions across Amazonia. In this study, six of these are formally named and described. The new species partly correspond to previously identified candidate lineages ‘sp. F’ and ‘sp. G’ and also to previously unreported lineages. Because of their rarity and unequal sampling effort of the A. heyeri clade across Amazonia, conservation assessments for the six newly described species are still premature. Regarding the biogeography of the A. heyeri clade, our data support a northern Amazonian origin with two independent dispersals into the South American Dry Diagonal. Although riverine barriers have a relevant role as environmental filters by isolating lineages in interfluves, dispersal rather than vicariance must have played a central role in the diversification of this frog clade.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
The ferric pseudobrookite is a rare example of uniaxial anisotropic spin-glass insulator, depicting a multiglass behavior and magnetoelectric coupling. Here, we present Raman spectroscopy results in ...order to elucidate the spin-phonon coupling in Fe2TiO5 for the first time. The experimental data are supported by computational simulations performed in view of density functional theory, which allowed us to assign the main Raman-active modes. Temperature-dependent phonon behavior exhibited anomalous evolution around 55 and 80–200 K, which was explained as successive coupling between lattice and spin configuration arising from spin freezing and short-range magnetic correlation, respectively. Arguments that the magnetoelectric effect in Fe2TiO5 is mediated by spin-phonon coupling are presented.
•Fe2TiO5 compound was synthesized by solid state route.•Phonon assignments were provided by DFT calculations.•Temperature-dependent Raman spectra were recorded.•Anomaly in phonon mode was detected below freezing transition.•Magnetoelectric effect may be mediated by spin-phonon coupling.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
It is known that barium disilicate (BS2) glass exhibits two prominent exothermic peaks between the glass transition and melting temperatures in calorimetric experiments, however, their cause is not ...known. In this work, glass-ceramic samples were produced inside a differential scanning calorimeter (DSC) and then investigated
ex situ
with X-ray diffraction (XRD) and Raman spectroscopy. We found that the first exothermic peak results from multiphase crystallization although a signature of residual glass is still observed. H-BaSi
2
O
5
, and Ba
3
Si
5
O
13
were directly identified after the first exothermic peak, however, both L-BaSi
2
O
5
and an unknown phase(s) are also formed. Rietveld analysis indicates <1% Ba
3
Si
5
0
13
in the sample heat treated at 853 °C (the first exothermic peak maximum). Amorphous halos are observed in the XRD patterns of samples heated to temperatures until the second exothermic peak. Raman spectra suggest that the crystalline phases are somewhat distorted or contain defects. The second exothermic peak is actually a composite peak composed of two contributions. We interpret these shoulders as separate processes including crystallization of non-stoichiometric phases, crystallization of the residual glass, and the phase transition of monoclinic H-BaSi
2
O
5
to orthorhombic L-BaSi
2
O
5
. After the second exothermic peak, the XRD and Raman spectra show that the samples have become L-BaSi
2
O
5
. These results clarify the relationships between thermal history and crystalline phase formation, which may be used to produce glass-ceramics with desirable properties.
Crystallization proceeds through high-temperature and non-stoichiometric phases which recrystallize to become sanbornite (BaSi
2
O
5
) during heating or through time.
The endoplasmic reticulum (ER) stress is one of the mechanisms related to decreased insulin secretion and beta cell death, contributing to the progress of type 2 diabetes mellitus (T2D). Thus, ...investigating agents that can influence this process would help prevent the development of T2D. Recently, the growth-hormone-releasing hormone (GHRH) action has been demonstrated in INS-1E cells, in which it increases cell proliferation and insulin secretion. As the effects of GHRH and its agonists have not been fully elucidated in the beta cell, we proposed to investigate them by evaluating the role of the GHRH agonist, MR-409, in cells under ER stress. Our results show that the agonist was unable to ameliorate or prevent ER stress. However, cells exposed to the agonist showed less oxidative stress and greater survival even under ER stress. The mechanisms by which GHRH agonist, MR-409, leads to these outcomes require further investigation.
•Agonist MR-409 decreases oxidative stress in insulin-secreting cells.•Agonist MR-409 demonstrates the anti-apoptotic action on cells under ER stress.•Agonist MR-409 modulates proteins of the Bcl-2 family.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Aim
To investigate the influence of breathing patterns and blood pressure behavior postural control in older adults.
Methods
A total of 20 older adults carried out spontaneous, controlled (15 ...cycles/min) and deep (6 cycles/min) breathing trials, in random order. In this session, the heart rate was recorded continuously and blood pressure measured every 3 min. In addition, the challenge from sitting to an active standing position was carried out with eyes closed during 6 min on a baropodometer plate with electromyography recording. The root mean square (RMS) of electromyography was calculated.
Results
There were significant differences in the postural control with spontaneous breathing from the first minute (center of pressure COP‐area 216.40 ± 116.70 mm2) in comparison with the third minute (COP‐area 79.35 ± 68.11 mm2; d = 0.89; P < 0.01) and the sixth minute (COP‐area 70.24 ± 41.26 mm2; d = 0.60; P < 0.05) of active standing. Furthermore, deep breathing significantly increases the COP‐area (158.50 ± 126.2 mm2) at the sixth minute of active standing in comparison with spontaneous breathing (70.24 ± 41.26 mm2; d = 0.80; P < 0.01). There were also significant differences in systolic blood pressure during spontaneous breathing between the baseline measures (sitting position 123 ± 11 mmHg) and the first minute of active standing (117 ± 13 mmHg; d = 0.24; P < 0.05). Furthermore, electromyography activity of the tibialis anterior increased during the deep (17.52 ± 9.21 RMS) and controlled breathing (16.75 ± 5.26 RMS) compared with the spontaneous condition (14.93 ± 5.56 RMS; d = 0.17; P < 0.05).
Conclusions
The present data provide important insight into the respiratory and hemodynamics effects of postural control in older adults. The current data confirm that deep breathing causes periodic perturbation in the neuromuscular compensation of the lower limbs. Geriatr Gerontol Int 2018; 18: 692–697.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
The renin angiotensin system (RAS) plays an important role in inflammation and fibrosis. The classical axis of the RAS, formed by angiotensin converting en-zyme (ACE), angiotensin II (Ang II) and ...angiotensin receptor type 1 (AT1), activates several cell functions and molecular signaling pathways related to tissue injury, inflammation and fibrosis. In sharp contrast, the RAS axis composed by angiotensin converting enzyme 2 (ACE2), angiotensin-(1-7) and Mas receptor exerts opposite effects in relation to inflammatory response and tissue fibrosis.
In this review, we have the aim to summarize recent findings on the anti-inflammatory and anti-fibrogenic role of ACE2/Ang-(1-7)/Mas axis in the context of basic research, experimental human dis-eases and clinical studies.
Several studies showed that ACE2/Angiotensin-(1-7)/Mas axis reduces cytokine release and inhibits signaling pathways of tissue fibrosis in experimental models of human diseases including atherosclerosis, cerebral ischemia, obesity, chronic kidney disease, liver diseases and asthma. On the other hand, very few data was provided by clinical studies.
Experimental studies clearly support the anti-inflammatory and anti-fibrotic effects of ACE2/ Ang-(1-7)/Mas axis. Clinical studies, especially phase III and IV trials, will be necessary to establish the therapeutic role of ACE2/Ang-(1-7)/Mas axis in controlling inflammation in different human diseases.
The outstanding species richness of Amazonia has fascinated biologists for centuries. However, the records of actual numbers and distribution of species forming its ecosystems are so incomplete that ...the understanding of the historical causes and regional determinants of this diversity remain speculative. Anuran clades have repeatedly been documented to harbour many unnamed species in this region, notably the Boana albopunctata species group. Considering the documented distribution and the ecology of the species of that group, we hypothesized that it diversified via successive trans-riverine dispersals during the late Miocene and Pliocene, after the formation of the modern Amazon watershed. To test this hypothesis, we gathered an extensive dataset of 16S rDNA sequences sampled throughout Amazonia and a mitogenomic dataset representative of the diversity of the clade to (1) re-evaluate species boundaries and distributions, and (2) infer the spatio-temporal history of diversification within Amazonia. We delimited 14 Operational Taxonomic Units (OTUs) in an Amazonian clade, i.e., 75% higher than currently recognized (14 OTUs for eight described species). Combining molecular data with morphological and acoustic data, two new species, Boana courtoisae sp. nov. from the eastern Guiana Shield and Boana eucharis sp. nov. from Southern Amazonia, are described herein. These species belong to a clade that diversified throughout Amazonia during the last 10 Ma, thus more recently than co-distributed small terrestrial anurans but concomitantly with other more vagile vertebrates. Our time-scaled phylogeny and biogeographic analyses suggest an initial east-west divergence and confirm reciprocal trans-riverine dispersals during the last 5 Ma. The geomorphological evolution of the region and species-specific dispersal ability largely explain these distinct spatio-temporal patterns across anurans.
http://www.zoobank.org/zoobank.org:act:4F8ACA9F-F6F1-4605-BD6C-6D4650AACCBE
http://www.zoobank.org/zoobank.org:act:51CC7B40-2D6B-4A9E-AF50-AB34D4CE1042
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BFBNIB, GIS, IJS, IZUM, KILJ, KISLJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Eugenol is a phenolic compound and the main constituent of the essential oil of clove India. Although there are reports of some pharmacological effects of eugenol, this study is the first that ...proposes to evaluate the antifungal effects of this phenol against both
and
cells. The effect of eugenol against yeast cells was analyzed for drug susceptibility, alterations in cell diameter, capsule properties, amounts of ergosterol, oxidative burst, and thermodynamics data. Data demonstrated that there is no interaction between eugenol and fluconazole and amphotericin B. Eugenol reduced the cell diameter and the capsule size, increased cell surface/volume, changed positively the cell surface charge of cryptococcal cells. We also verified increased levels of reactive oxygen species without activation of antioxidant enzymes, leading to increased lipid peroxidation, mitochondrial membrane depolarization and reduction of lysosomal integrity in cryptococcal cells. Additionally, the results showed that there is no significant molecular interaction between eugenol and
. Morphological alterations, changes of cellular superficial charges and oxidative stress play an important role in antifungal activity of eugenol against
and
that could be used as an auxiliary treatment to cutaneous cryptococcosis.
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