Similar Elevations Research Articles

Aboveground biomass in secondary montane forests in Peru: Slow carbon recovery in agroforestry legacies

Andean tropical montane forests (TMF) are hotspots of biodiversity that provide fundamental hydrological services as well as carbon sequestration and storage. Agroforestry systems occupy large areas in the Andes but climatic pressures, market volatility and diseases may result inagroforest abandonment, promoting secondary succession. Secondary forests are well-adapted and efficient carbon sinks whose conservation is vital to mitigate and adapt to climate change and to support biodiversity. Little is known, however, about how secondary TMF recover their aboveground biomass (AGB) and composition after abandonment. We established a 1.5 ha plot at 1780 masl on a 30-year old abandoned agroforest and compared it against two control forest plots at similar elevations. Agroforestry legacies influenced AGB leading to far lower stocks (42.3 ± 5.4–59.6 ± 7.9 Mg ha−1 using allometric equations) than those expected after 30 years (106 ± 33 Mg ha−1) based on IPCC standard growth rates for secondary montane forests. This suggests a regional overestimation of mitigation potentials when using IPCC standards. Satellite-derived AGB largely overestimated our plot values (179 ± 27.3 Mg ha−1). Secondary growth rates (1.41–2.0 Mg ha−1 yr−1 for DBH ≥ 10 cm) indicate recovery times of ca. 69 to 97 years to reach average control AGB values (137 ± 12.3 Mg ha−1). This is 26 years above the average residence time of montane forests at our elevation (71 ± 1.91 years) suggesting a non-recovery or far slower recovery to control AGB values. Three variables appear to define this outcome compared to the control plots: lower DBH (15.8 ± 5.9 cm vs 19.8 ± 11.0 cm), lower basal area (12.67 ± 0.7 vs 28.03 ± 1.5 m2 ha−1) and higher abundance of lighter-wood tree genera (0.46 ± 0.10 vs 0.57 ± 0.11 gr cm3) such as Inga, a common shade-tree in Andean agroforests. With 3.2 million hectares committed to restoration, Peru needs to target currently neglected TMF recovery schemes to support biodiversity, water and carbon storage and fulfill its international commitments.

Evaluating Assisted Gene Flow in Marginal Populations of a High Mountain Species

Many species cannot either migrate or adapt at the rate of temperature increases due to climate warming. Therefore, they need active conservation strategies to avoid extinction. Facilitated adaptation actions, such assisted gene flow, aim at the increase of the evolutionary resilience of species affected by global change. In elevational gradients, marginal populations at the lower elevation edges are experiencing earlier snowmelt and higher temperatures, which force them to adapt to the new conditions by modifying their phenology. In this context, advancing the onset of flowering and seed germination times are crucial to ensure reproductive success and increase seedling survival prior to summer drought. Assisted gene flow may bring adaptive alleles and increase genetic diversity that can help throughout ontogeny. The main aim of this work is to assess the effects that different gene flow treatments could have on the desired trait changes in marginal populations. Accordingly, we established a common garden experiment in which we assayed four different gene flow treatments betweenSilene ciliataPourr. (Caryophyllaceae) populations located in similar and different elevation edges, belonging to the same and different mountains. As a control treatment, within-population crosses of low elevation edge populations were performed. The resulting seeds were sown and the germination and flowering onset dates of the resulting plants recorded, as well as the seedling survival. Gene flow between populations falling on the same mountain and same elevation and gene flow from high-elevation populations from a different mountain to low-elevation populations advanced seed germination time with respect to control crosses. No significant effects of gene flow on seedling survival were found. All the gene flow treatments delayed the onset of flowering with respect to control crosses and this effect was more pronounced in among-mountain gene flows. The results of this study highlight two important issues that should be thoroughly studied before attempting to apply assisted gene flow in practical conservation situations. Firstly, among-populations gene flow can trigger different responses in crucial traits throughout the ontogeny of plant species. Secondly, the population provenance of gene flow is determinant and plays a significant role on the effects of gene flow.

Do Colleges Perform the Same Following Developmental Education Reform? The Case of Florida\u2019s Senate Bill 1720

Developmental education (DE) reform took place among the 28 Florida College System (FCS) institutions in 2014. In this study, we examine how cohort-based passing rates in college-level English and math courses changed at different colleges for pre- and post-policy period and explore what institutional characteristics were related with various institutional trajectories of cohort-based course passing rates in the post-policy period. Employing longitudinal data analysis, we found that colleges performed similarly regarding cohort-based passing rates in both college-level English and combined math courses before DE reform and had a similar elevation in the cohort-based English course passing rates when DE reform took place in 2014. However, colleges experienced different change patterns in the years following DE reform. Specifically, colleges located in rural areas and with more White students experienced relatively lower college-level English passing rates in the post-policy period than their counterparts. Different colleges had slight differences in the trajectory of college-level math passing rates by cohort after SB 1720 in 2014, but institutional characteristics in this study did not adequately capture inter-institutional differences.

Palynological investigations reveal Eemian interglacial vegetation dynamics at Spiezberg, Bernese Alps, Switzerland

Interglacial pollen records are valuable archives of past vegetation dynamics and provide important information about vegetation responses to different-than-today climates. Interglacial pollen archives pre-dating the Last Glacial Maximum (LGM) are scarce on the Swiss Plateau in contrast to the many available Late Glacial and Holocene records. This is mainly due to the rapidly changing palaeo-environmental conditions throughout the Quaternary and the low preservation potential of material suitable for palynological investigations. The Spiezberg site offers a palynological record situated most proximal to the Alps in Switzerland. Previous investigations tentatively assigned this record to the Eemian interglacial (MIS 5e). We have conducted additional pollen analytical investigations to increase the quantity of pollen information. Besides biostratigraphic interpretations, we use numerical methods such as distance analysis (distantia) and ordination techniques (PCA) to evaluate the similarities and differences between the Spiezberg record and its geographically and chronostratigraphically closest physically dated (U/Th, luminescence) analogues from the Eemian (MIS 5e) and Meikirch 3 (MIS 7a) interglacials. Our palynological investigations reveal the predominance of closed temperate forests with abundant fir (Abies) and spruce (Picea) as well as evergreen broad-leaved taxa (e.g. Hedera). The attribution to the Eemian interglacial relies on the observation of very rare beech (Fagus) occurrences, a phase with prominent yew (Taxus) and the unimportance of hornbeam (Carpinus), all of which are typical Eemian features on the Swiss Plateau. An Eemian age is supported by the numerical comparison with the Beerenmösli (MIS 5e) and Meikirch 3 (MIS 7a) reference records. Furthermore, the Picea, Taxus and Fagus dynamics observed on the Swiss Plateau during the Eemian are in excellent agreement with vegetational patterns observed elsewhere in Central Europe. Surprisingly, Carpinus was almost absent on the Swiss Plateau during the Eemian, whereas it was a major component of the forest at other European sites with a similar elevation as Spiezberg. We explain this by environmental conditions and the strong competition with Abies alba. In particular, considering the European Eemian vegetation history and the results of our reconstructions from the Swiss Plateau, we find that Abies alba was a highly competitive tree under natural warmer-than-today conditions. This finding provides further evidence that Abies alba may benefit from future climate warming.

A new species of Cumulopuntia (Cactaceae) from north-western Bolivia

A new species of Cumulopuntia (C. flexibilispina) from north-west Bolivia, which forms hemispherical clumps with dense flexible white spination, is described and illustrated. The species is only known from very high elevations between 4,400m and 4,650m. The new species is compared with and key differences are noted from four other high elevation cumulopuntias: the widespread C. boliviana (including C. boliviana subsp. dactylifera) from Peru, Bolivia and Argentina; C. glomerata (C. boliviana subsp. ignescens) which is found at similar high elevations but in more arid conditions further to the west in Peru, Bolivia and Chile; C. chichensis from southern Bolivia and northern Argentina and finally C. echinacea from southern Peru and northern Chile.

Analysis of differential neonatal lethality in cystathionine β-synthase deficient mouse models using metabolic profiling.

Cystathionine beta-synthase (CBS) is a key enzyme of the trans-sulfuration pathway that converts homocysteine to cystathionine. Loss of CBS activity due to mutation results in CBS deficiency, an inborn error of metabolism characterized by extreme elevation of plasma total homocysteine (tHcy). C57BL6 mice containing either a homozygous null mutation in the cystathionine β-synthase (Cbs-/- ) gene or an inactive human CBS protein (Tg-G307S Cbs-/- ) are born in mendelian numbers, but the vast majority die between 18 and 21 days of age due to liver failure. However, adult Cbs null mice that express a hypomorphic allele of human CBS as a transgene (Tg-I278T Cbs-/- ) show almost no neonatal lethality despite having serum tHcy levels similar to mice with no CBS activity. Here, we characterize liver and serum metabolites in neonatal Cbs+/- , Tg-G307S Cbs-/- , and Tg-I278T Cbs-/- mice at 6, 10, and 17 days of age to understand this difference. In serum, we observe similar elevations in tHcy in both Tg-G307S Cbs-/- and Tg-I278T Cbs-/- compared to control animals, but methionine is much more severely elevated in Tg-G307S Cbs-/- mice. Large scale metabolomic analysis of liver tissue confirms that both methionine and methionine-sulfoxide are significantly more elevated in Tg-G307S Cbs-/- animals, along with significant differences in several other metabolites including hexoses, amino acids, other amines, lipids, and carboxylic acids. Our data are consistent with a model that the neonatal lethality observed in CBS-null mice is driven by excess methionine resulting in increased stress on a variety of related pathways including the urea cycle, TCA cycle, gluconeogenesis, and phosphatidylcholine biosynthesis.

Late Pleistocene baldcypress (Taxodium distichum) forest deposit on the continental shelf of the northern Gulf of Mexico

Approximately 13 km south of Gulf Shores, Alabama (United States), divers found in situ baldcypress (Taxodium distichum) stumps 18 m below the ocean surface. These trees could have only lived when sea level fell during the Pleistocene subaerially exposing the tectonically stable continental shelf. Here we investigate the geophysical properties along with microfossil and stratigraphical analyses of sediment cores to understand the factors that lead to this wood’s preservation. The stumps are exposed in an elongated depression (~100 m long, ~1 m deep) nested in a trough of the northwest–southeast trending Holocene sand ridges and troughs with 2–5 m vertical relief and ~0.5 km wavelength. Radiocarbon ages of the wood were infinite thus optically stimulated luminescence (OSL) dating was used to constrain the site’s age. Below the Holocene sands (~0.1–4 m thick), separated by a regional erosional unconformity, are Late Pleistocene mud‐peat (72±8 ka OSL), mud‐sand (63±5, 73±6 ka OSL), and palaeosol (56±5 ka OSL) facies that grade laterally from west to east, respectively. Foraminiferal analysis reveals the location of the terrestrial‐marine transitional layer above the Pleistocene facies in an interbedded sand and mud facies (3940±30 (1σ) 14C a BP), which is part of a lower shoreface or marine‐dominated estuarine environment. The occurrence of palaeosol and swamp facies of broadly similar ages and elevation suggests the glacial landscape possessed topographic relief that allowed wood, mud and peats to be preserved for ~50 ka of subaerial exposure before transitioning to the modern marine environment. We hypothesize that rapid sea‐level rise occurring ~60 or ~40 ka ago provided opportunities for local flood‐plain aggradation to bury the swamp thus preserving the stumps and that other sites may exist in the northern Gulf of Mexico shelf.

Maternal and Fetal Defects of Gestational Angiotensin 1‐7 Receptor Antagonism: A Possible Preclinical Model of Preeclampsia

Preeclampsia (PE) is a complex pathological state associated with serious adverse maternal and fetal consequences. Imbalances of the pressor ACE/Ang II and depressor ACE2/Ang 1-7 arms of renin-angiotensin system are implicated in PE pathophysiology. The current experimental study investigated whether the blockade of Ang 1-7 receptors (Mas receptors) during late pregnancy would replicate clinical features of PE. Two different dosing regimens of A779 (Mas receptor antagonist, 0.750 and 1.3 mg/kg/day s.c.) were administered daily to pregnant rats for 7 consecutive days starting from gestational day 14. The developed maternal and fetal abnormalities were compared to those produced by gestational L-NAME administration (50 mg/kg/day for 7 days), a standard model of PE in rodents. Gestational administration of L-NAME or A779 reduced weight and number of placentas and pups and increased death and resorption percentages of pups. These effects were more evident with the lower dose of A779 than with the higher dose. Moreover, A779 or L-NAME provoked similar elevations in systolic blood pressure and proteinuria. Immunohistochemical studies on placental tissues revealed enhanced protein expression of NFκB in dams treated with L-NAME or the lower, but not higher, dose of A779. While placental ACE expression remained unaltered, ACE2 expression was upregulated by A779 and L-NAME. Studies in isolated perfused kidneys demonstrated diminished acetylcholine vasodilation in L-NAME, but not A779, challenged preparations. Neither drug affected renal vasoconstriction induced by Ang II or phenylephrine. The current data highlight the likelihood of exploiting pregnant dams with pharmacologically eliminated Mas receptors for PE modeling in rodents. However, more studies are needed to further validate the model fidelity and its intimate resemblance to human PE.

Stable isotopes of recharge to the alpine epikarst landscape of the wasatch mountains, Utah USA

Study RegionThis study considers the hydrogeology of alpine epikarst by deciphering the controls on water isotopes from pools in the Timpanogos Caves and the American Fork River in the Wasatch Mountains of central Utah. Study FocusFrom prior research in the Timpanogos Caves, recharge to some cave pools is via diffuse flow through the fractured rock matrix. Other pools receive recharge by direct infiltration through the epikarst above the cave either by open fractures or by piston flow through an epikarst reservoir. Herein, δ18O and δ2H from water samples collected in 2012 from five cave pools yield connections to the source elevations of recharge in the overlying alpine epikarst, despite the cave pools having similar elevations. New Hydrological Insights for the RegionRegardless of the recharge mechanism, δ18O and δ2H values vary between the peak recharge season in April–May and a peak evaporation season from June–August, result from seasonal changes in precipitation source, freeze-thaw cycles, and sublimation of snow prior to melt and infiltration. By ascribing likely elevations to the sources of recharge, based upon epikarst geometry and supporting geochemical evidence, we demonstrate that values of δ18O and δ2H vary along an altitude lapse rate of -4.8‰/km for δ18O and -35.7‰/km for δ2H.

Functional modulation of phosphodiesterase-6 by calcium in mouse rod photoreceptors

Phosphodiesterase-6 (PDE6) is a key protein in the G-protein cascade converting photon information to bioelectrical signals in vertebrate photoreceptor cells. Here, we demonstrate that PDE6 is regulated by calcium, contrary to the common view that PDE1 is the unique PDE class whose activity is modulated by intracellular Ca2+. To broaden the operating range of photoreceptors, mammalian rod photoresponse recovery is accelerated mainly by two calcium sensor proteins: recoverin, modulating the lifetime of activated rhodopsin, and guanylate cyclase-activating proteins (GCAPs), regulating the cGMP synthesis. We found that decreasing rod intracellular Ca2+ concentration accelerates the flash response recovery and increases the basal PDE6 activity (βdark) maximally by ~ 30% when recording local electroretinography across the rod outer segment layer from GCAPs−/− recoverin−/− mice. Our modeling shows that a similar elevation in βdark can fully explain the observed acceleration of flash response recovery in low Ca2+. Additionally, a reduction of the free Ca2+ in GCAPs−/− recoverin−/− rods shifted the inhibition constants of competitive PDE inhibitor 3-isobutyl-1-methylxanthine (IBMX) against the thermally activated and light-activated forms of PDE6 to opposite directions, indicating a complex interaction between IBMX, PDE6, and calcium. The discovered regulation of PDE6 is a previously unknown mechanism in the Ca2+-mediated modulation of rod light sensitivity.

Conceptual Design of Gas Distribution Pipeline Network for Estates in Nigeria

This work presents the conceptual design of a gas distribution pipeline network for estates in Nigeria using the University of Abuja Staff Quarters as a case study. The problem statement was the aggressive consumption of cooking gas, referred to as liquefied petroleum gas (LPG), without gas pipeline networks infrastructures to homes and estates across Nigeria but relies on cylinders with its attendant danger. The methodology includes the determination of the gas demand from the average monthly gas consumption in each of the households, the elevation head, diameter of the pipelines, gas velocity, gas mass flow rate, head losses and the pressure drop analysis of series (option 1), parallel (option 2) and grid (option 3) options. The results obtained indicate that the best gas distribution design option for the trunk, reticulation and service pipelines was the grid connections to minimize investment costs with equitable pressures at service outlets. In the selected design option, the total length of the 50.8 mm diameter trunk pipelines was 19.52 m, while the total length of the 12.7 mm diameter reticulation and service pipelines were 3,223.34 m and 1,648.46 m respectively. The quantities of fittings required for the pipeline network layout were determined for an estate of 124 houses. The mass flow rates of the LPG in the 3 pipeline sections were found to be 0.39 kg/s and total head loss based on local resistance coefficients was found to be lowest in option 3 (1,568.33 m), which also has the least pressure drop of 67.84 kPa in the trunk and reticulation pipelines. It can be concluded that the optimized design could be adopted for the gas distribution pipeline network of University of Abuja staff quarters and other estates in Nigeria, with similar elevation and buildings layout.

Forest Thinning in Ponderosa Pines Increases Carbon Use Efficiency and Energy Flow From Primary Producers to Primary Consumers

AbstractA better understanding of carbon use efficiency (CUE) and carbon allocation during disturbance is critical to improve simulations of the global carbon cycle and understanding future climate impacts. Forest thinning of high‐stem density, high elevation dry western US forests is becoming more common to reduce severe fire danger but there are uncertainties about how forest thinning may impact forest CUE, carbon allocation and energy flow through the food chain. In three, quarter ha stands with similar soils, elevation and climate along a forest thinning gradient near Flagstaff (AZ), we measured total net primary production (NPP of wood, fine root, and leaves), total autotrophic respiration (Ra of wood, rhizosphere, and canopy respiration), gross primary production (GPP = NPP + Ra) and large mammal herbivory (with camera traps and dung counts) over a ∼2‐year period. We found strong seasonality in all carbon cycling variables and herbivory, peaking during the warm, wet monsoon period. Carbon was produced more efficiently in the thinned stands, with carbon use efficiency (CUE = NPP/GPP) of ∼0.63, versus the unthinned stand with CUE of 0.38. GPP was similar in the two thinned stands (∼3.5 Mg C ha−1 yr−1) but was about 30% greater in the unthinned stands (5.0 Mg C ha−1 yr−1). Finally, the thinned stand had higher understory NPP, large herbivore consumption and had triple the total energy going into primary consumers. Overall, the thinning, and the return to a more natural prefire suppression forest structure, increased the CUE and energy flow from primary producers to primary consumers.

Aphrodisiac potential of Polyalthia bullata (Tongkat Ali) in fowl

Objective: To study the aphrodisiac potential of Polyalthia (P.) bullata in fowl. Methods: In this study, testosterone, as an indicator of the aphrodisiac potential of P. bullata, was investigated for its release from TM3 Leydig cells grown in vitro and in 4 fowls given capsules containing P. bullata at a dose of 10 mg in each capsule twice a day, for 50 days. In the latter in vivo evaluation, mating behaviours were additionally determined after the treated fowls were released to the individual hens, and their testes and liver were dissected for histological examinations. Blood drawn from the fowls was assessed for any changes in diagnostic parameters. Results: In the in vitro test (TM3 Leydig cells), P. bullata was able to increase testosterone to 0.48 nmol/L within 72 h of incubation, compared to the untreated control with only 0.18 nmol/L, i.e., an increase of 170%. In the in vivo test, outcomes in the fowls dosed with P. bullata showed similar positive elevations of testosterone to (9.72±1.10) nmol/L in comparison to the controls that showed a level of only (4.05±0.84) nmol/L. Total frequencies of mating behaviours were observed (wing flapping, body shakes, crowing and beak pecking) to be 23 counts for the test compared to only 15 for the control fowls. Histological examination of the male reproductive organs provided evidence of testosterone boosting based on an observable increase in the activity at the seminiferous tubules of testis tissues without any damaging effects, compared to the controls. In the nine diagnostic blood parameters assessed, including alanine aminotransferase, aspartate aminotransferase, and gamma glutamyltransferase, none was remarkably elevated compared to the controls. The histological changes in the liver were not severe and mainly consisted of only localized moderate but recoverable obstructions and swellings of the vessels and tubules. Conclusions: P. bullata is able to boost testosterone both in vitro and in vivo, with no acute toxicities.

Evidence of Brood Parasitism and Quantification of Rangewide Overlap between the Olive Warbler and Brown-headed Cowbird

Brood parasitism is a fascinating natural history phenomenon that provides a window into the coevolution of antagonistic interactions. Many ecological and evolutionary aspects of brood parasitism remain unknown, and new hosts of brood parasites are still being discovered. We document the second instance of brood parasitism of the Olive Warbler (Peucedramus taeniatus) by the Brown-headed Cowbird (Molothrus ater). Apparent lack of habitat and elevation overlap across the ranges of these two species prompted us to examine how frequently they come into contact. We analyzed >3 million Olive Warbler and Brown-headed Cowbird occurrence records from two open-source repositories, eBird and GBIF, to examine both synchronous and asynchronous locality overlap during the breeding season. We found that the two species were documented together simultaneously in only 3.1% of analyzed instances, but that they co-occurred in similar habitat types and/or at similar elevations at 11.8% of localities analyzed across the Olive Warbler’s range. Additional research on aspects of ecology and evolution, such as host selection, the cowbird’s diurnal patterns of movement, and the dynamics of intracellular pathogens infecting brood parasites and their hosts, may shed light more broadly on the ecological interactions and mechanisms underlying brood parasitism.

Phenological shift along an elevational gradient and dispersal of pollen and seeds maintain a hybrid zone between two cherry tree species

AbstractHybrid zones between species with staggered reproductive phenology sometimes occur along elevational gradients. The maintenance of such hybrid zones may depend on elevational shift in phenology and vertical dispersal of pollen and seeds. In a hybrid zone of Cerasus leveilleana (Cl) and C. sargentii (Cs), 111 adults, 372 embryos of 65 mothers, and 133 juveniles were sampled across elevations of 900–1,400 m in central Japan. Using the hybrid index estimated from nuclear microsatellites, the samples were assigned to Cl, Cs or their hybrid taxon. Cs was in higher elevations than Cl with an overlapping range, and their hybrids were in intermediary elevations. Flowering periods were earlier in Cs than in Cl with little overlap at the same elevation and were intermediate in their hybrids. Flowering periods were delayed in higher elevations and overlapped between Cl and Cs in different elevations. Fruiting periods were slightly earlier in Cs than in Cl but were largely overlapped. Effective pollinators and seed dispersers were common among the taxa. Changes in the hybrid index from mothers to their embryos were larger in hybrid mothers than in Cl or Cs mothers, indicating mating of hybrids with diverse taxa. In Cs, juveniles were more abundant in lower elevations than embryos, indicating downhill seed dispersal. Proportions of hybrids were 19% in embryos, 17% in juveniles and 12% in adults. The findings suggest that the hybrid zone is maintained by interspecific pollination between different elevations, backcrossing with hybrids at similar elevations, vertical seed dispersal and mild selection against hybrids.

Ameliorative role of Ulva extract against heavy metal mixture-induced cardiovascular through oxidative/antioxidant pathways and inflammatory biomarkers.

The current study investigates the therapeutic and curative effect of Ulva lactuca polyphenolic extract (ULPE) in general and particularly polyphenolics compounds against heavy metal mixture (HME). The toxicity behind heavy metal is due to oxidative stress resulted from heavy metals pollution or administration through contaminated food (vegetables, water, and fish). Heavy metal toxicity plays a major role in different cardiovascular diseases. The objective of this study is aimed to examine the protective effect of ULPE against heavy metal mixture induced cardiovascular diseases through oxidative/antioxidant and inflammatory pathways. Sixty male rats (Sprague-Dawley) were assigned to six groups. Group I served as the control, group II served as the induced group receiving subcutaneously for 7 days 0.25 mg/100 gm body weight/day heavy metal mixtures (Equal concentration of Ni, Cd, Co and Hg chloride, and Pb acetate), group III received (i.p.) ULPE of dose 30 mg for 15 days, group IV served as the protected group pretreated with ULPE for 15 days as a protection dose, and then treated with the heavy metal-mixture, group V served as protected standard group pretreated with vitamin C (VitC ) (50 mg/Kg) and then treated with the heavy metal-mixture, and group VI served as standard group treated with VitC (50 mg/Kg). The main pathological changes within the heart revealed heart inflammation after heavy-metal mixtures administrations. On contrast to the protected group treated with ULPE (group IV), the protection group (group II) showed a significant increase in the antioxidant as well as anti-inflammatory biomarker. The cardiovascular biomarkers (Troponin T, CRP, and BNP) showed similar attitude elevations in induction group and decreased greatly in protection and VitC group. The antioxidant and the anti-inflammatory activities of ULPE are a consequence of their higher polyphenolic contents as well as marine secondary metabolites which are confirmed using qualitative and quantitative analysis. From the current result, we concluded that ULPE possesses a cardiovascular protective agent as a result of highly contents of different bioactive secondary metabolites which have antioxidant as well as free-radical scavenging and anti-inflammatory activates. Showed the mechanism of ULPE as cardioprotective against heavy metal mixture.

Mir21 modulates inflammation and sensorimotor deficits in cervical myelopathy: data from humans and animal models.

Degenerative cervical myelopathy is a common condition resulting from chronic compression of the spinal cord by degenerating structures of the spine. Degenerative cervical myelopathy present a wide range of outcomes, and the biological factors underlying this variability are poorly understood. Previous studies have found elevated MIR21-5p in the sub-acute and chronic neuroinflammatory environment after spinal cord injury. As chronic spinal cord neuroinflammation is a major feature of degenerative cervical myelopathy, we hypothesized that MIR21-5p may be particularly relevant to disease pathobiology, and could serve as a potential biomarker. A prospective cohort study of 69 human degenerative cervical myelopathy patients (36 male:33 female) between the ages of 30 and 78 years was performed to identify the relationship between MIR21-5p expression, symptom severity and treatment outcomes. Results from this study identified a positive correlation between elevated plasma MIR21-5p expression, initial symptom severity and poor treatment outcomes. Subsequent validation of these relationships using a mouse model of degenerative cervical myelopathy identified a similar elevation of MIR21-5p expression at 6 and 12 weeks after onset, corresponding to moderate to severe neurological deficits. To further determine how MIR21-5p affects cervical myelopathy pathobiology, this mouse model was applied to a Mir21 knockout mouse line. Deletion of the Mir21 gene preserved locomotor function on rotarod and forced swim tests, but also resulted in increased nociception based on tail flick, Von Frey filament and electrophysiological testing. Critically, Mir21 knockout mice also had reduced spinal cord inflammation, demonstrated by the reduction of Iba1+ microglia by ∼50% relative to wild-type controls. In vitro experiments using primary microglial cultures confirmed that MIR21-5p expression was greatly increased after exposure to lipopolysaccharide (pro-inflammatory), Il4 (anti-inflammatory) and hypoxia. Mir21 knockout did not appear to alter the ability of microglia to respond to these stimuli, as expression of key pro- and anti-inflammatory response genes was not significantly altered. However, target prediction algorithms identified the IL6/STAT3 pathway as a potential downstream target of MIR21-5p, and subsequent in vitro testing found that expression of components of the IL6 receptor complex, Il6ra and Il6st, were significantly higher in Mir21 knockout microglia. In aggregate, these data show that Mir21 plays a role in the progression of motor deficits and neuroinflammatory modulation in degenerative cervical myelopathy. Given this role in neuroinflammation, and its association with poor patient outcomes, MIR21-5p represents a potential therapeutic target and a new marker for prognostication.

Origins of the upland avifauna of Yapen Island, New Guinea region

New Guinea's mountains consist today of the high Central Range, plus ten isolated lower outlying ranges. But during Pleistocene periods of low sea level, when New Guinea's current shallow continental shelf was exposed as dry land, the main island included further outliers that subsequently became cut off as land-bridge islands as rising sea levels submerged the shelf connecting them to New Guinea. We surveyed the upland avifauna of Yapen, the highest of those land-bridge islands. Yapen supports 26 upland species. That number is higher than on nearby oceanic islands of similar elevation, because Yapen in contrast to oceanic islands could acquire species overland during the Pleistocene. However, that number is much lower than on New Guinea's outliers of similar elevation, due to extinctions of many of Yapen's populations following its isolation as an island.Of New Guinea's 193 upland species, some are much more widely distributed on the ten outliers than the rest. Yapen's upland species, and those of the other land-bridge islands, are a small subset of those successful colonists of mainland outliers. Part of the explanation for differential success is that only species whose elevational floors lie well below the summits of the outliers and of Yapen are likely to have survived on or colonised those mountains, all much lower than New Guinea's Central Range. For the remainder, we infer that more than half of Yapen's former upland populations have gone extinct since Yapen's isolation. For those species with poor ability to disperse overwater, abundance is a predictor of survival and continued presence on Yapen—as expected from the inverse relationship between extinction risk and population size.We identify half-a-dozen mechanisms for colonisation by upland species: dispersal overwater when Yapen was an island; regular post-breeding descent to the lowlands; irregular straggling to the lowlands; dispersal through flat lowlands; dispersal over hill bridges; and dispersal during cool Pleistocene phases, when some current upland species had lowland populations. Relict sets of those mostly vanished Pleistocene lowland populations survive on three remnant fragments of southern New Guinea's former Arafura platform: on the Aru Islands, New Guinea's Fly River bulge, and the northern tip of Australia's Cape York Peninsula.

Transition from a Subaerial to a Subnival Permafrost Temperature Regime Following Increased Snow Cover (Livingston Island, Maritime Antarctic)

The Antarctic Peninsula (AP) region has been one of the regions on Earth with strongest warming since 1950. However, the northwest of the AP showed a cooling from 2000 to 2015, which had local consequences with an increase in snow accumulation and a deceleration in the loss of mass from glaciers. In this paper, we studied the effects of increased snow accumulation in the permafrost thermal regime in two boreholes (PG1 and PG2) in Livingston Island, South Shetlands Archipelago, from 2009 to 2015. The two boreholes located c. 300 m apart but at similar elevation showed different snow accumulation, with PG2 becoming completely covered with snow all year long, while the other remained mostly snow free during the summer. The analysis of the thermal regimes and of the estimated soil surface energy exchange during the study period showed the effects of snow insulation in reducing the active layer thickness. These effects were especially relevant in PG2, which transitioned from a subaerial to a subnival regime. There, permafrost aggraded from below, with the active layer completely disappearing and the efficiency of thermal insulation by the snowpack prevailing in the thermal regime. This situation may be used as an analogue for the transition from a periglacial to a subglacial environment in longer periods of cooling in the paleoenvironmental record.

Possible cardioprotective role of NaHS on ECG and oxidative stress markers in an unpredictable chronic mild stress model in rats.

The protective effect of H2S against various body organ injuries has been described. The aim of this work is to investigate the potential role of sodium hydrosulfide (NaHS) as an H2S donor in chronic mild stress induced changes in the rat heart. Forty adult male Sprague Dawley rats were assigned to four groups: control, stressed group, stressed rats treated with aminooxyacetic acid (AOAA), and stressed rats treated with NaHS. Arterial blood pressure (ABP) was recorded. Serum adrenaline, MDA, and GSH levels were measured. Chronic stress significantly increased HR and ABP. AOAA produced similar changes, while NaHS mitigated the rise in HR and ABP. Both stressed and AOAA-treated stressed groups showed a significant decrease in QRS amplitude and a shortening of the RR, QT, and QTc intervals with an elevation of the ST segment. NaHS produced a significant improvement in ECG recordings. Chronic stress produced a significant rise of adrenaline and MDA levels with a significant decline in GSH levels. The AOAA-treated stressed group showed similar elevations. NaHS treatment caused significant reduction in adrenaline and MDA levels but significantly improved GSH levels. In conclusion, H2S donor has a cardioprotective effect against stress-induced cardiovascular diseases through amelioration of the oxidative stress and raised adrenaline levels induced by chronic stress exposure.