Integrated growth patterns of turtle grass,Thalassia testudinum Banks ex König

Indications of physiological integration in the clonal plant Thalassia testudinum Banks ex König from the Puerto Morelos reef lagoon, Mexican Caribbean, were deduced from synchronisation in the formation of ‘inactive shoots’, lateral rhizomes and inflorescences. ‘Inactive shoots’ (i.e. bare, pointed shoots with live roots attached) on a rhizome section often had similar numbers of leaf scars. Lateral rhizome sections were generally found in similar positions when a rhizome had more than one shoot bearing a lateral rhizome. Additionally, the position of lateral rhizomes and the number of leaf scars on inactive shoots were often similar when encountered on the same rhizome section. Synchronisation of flowering events was suggested by the similar position of inflorescence scars on different shoots on the same rhizome section. It is suggested that inactive shoots can play a role in density regulation of the clonal population, and that they possibly constitute a ‘dormant meristem bank’ analogous to ‘seed banks’, or ‘dormant bud banks’.     

Repair of UVB-Damaged Skin by the Antioxidant Sulphated Flavone Glycoside Thalassiolin B Isolated from the Marine Plant Thalassia testudinum Banks ex König

Daily topical application of the aqueous ethanolic extract of the marine sea grass, Thalassia testudinum, on mice skin exposed to UVB radiation resulted in a dose-dependent recovery of the skin macroscopic alterations over a 6-day period. Maximal effect (90%) occurred at a dose of 240 μg/cm², with no additional effects at higher doses. Bioassay-guided fractionation of the plant extract resulted in the isolation of thalassiolin B (1). Topical application of 1 (240 μg/cm²) markedly reduces skin UVB-induced damage. In addition, thalassiolin B scavenged 2,2-diphenyl-2-picrylhydrazyl radical with an EC₅₀ = 100 μg/ml. These results suggest that thalassiolin B is responsible for the skin-regenerating effects of the crude extract of T. testudinum. Erik L. Regalado and María Rodríguez have contributed equally to this work and should be considered as first authors.     

Spatial and temporal variation in the vegetation of dune slacks in relation to the ground water régime

Summary The aim of the study presented here is to determine the relation between the vegetation and the ground water régime in the dune slacks on the island of Voorne. A distinction is made between the spatial and the temporal variation in the vegetation. On the basis of data from a transect the relation between the spatial variation and the water-table is determined. With respect to the temporal variation data recorded on permanent plots were used. Both the variation in space and that in time proved to be related to differences in the ground water régime. The supposition is put forward that the amount of variation in time depends on the height of site relative to the water-table.Contribution to the Symposium of the Working Group on Succession Research on Permanent Plots held at Yerseke, the Netherlands, October 1975.Nomenclature of phanerogams follows Heukels & van Ooststroom 1975, Flora van Nederland, 18e druk Wolters-Noordhoff, Groningen; that of bryophytes Margadant 1959, Mossentabel, 3e druk, Amsterdam.The author is very much indebted to Mr. P.A. Bakker, Society for the Preservation of Nature reserves in the Netherlands, for the use of the 1966 relevé of site 46, and to Mr. W. Smant for his assistance in field work and the preparation of the data.     

Potential bangle (Zingiber montanum J.König) rhizome extract as a supplement to prevent and reduce symptoms of Covid-19

The morbidity and mortality rates due to Covid-19 are increasing day by day, to overcome this, we urgently need a better treatment strategy, therefore various ways and strategies for this must be pursued. The purpose of the present review is to explain that the rhizome of bangle (Zingiber montanum) has great potential to increase antibodies and reduce symptoms of acute respiratory distress syndrome (ARDS), which also seems suitable for treating Covid-19. Method: This review is looking for the results of scientific research from various sources, regarding the efficacy of bangle (Zingiber montanum) rhizome which is strongly suspected to be able to prevent, and reduce the symptoms that occur in COVID-19. The results showed that the bangle rhizome extract had activity as immunomodulatory, antiviral and reduced symptoms such as what happened in COVID-19. Conclusion: Bangle rhizome extract has dozens of nutritious substances and has multifunctional activities, and it can be postulated that among the benefits of bangle rhizome extract it is able to prevent and reduce symptoms that occur in Covid-19, and preclinical studies and clinical studies are needed to prove this postulate.     

Genetic susceptibility to dyslipidemia and incidence of cardiovascular disease depending on a diet quality index in the Malmö Diet and Cancer cohort

Background

By taking diet quality into account, we may clarify the relationship between genetically elevated triglycerides (TG) and low-density lipoprotein-cholesterol (LDL-C), and better understand the inconsistent results regarding genetically elevated high-density lipoprotein-cholesterol (HDL-C), and cardiovascular disease (CVD) risk.

Methods

We included 24,799 participants (62 % women, age 44–74 years) from the Malmö Diet and Cancer cohort. During a mean follow-up time of 15 years, 3068 incident CVD cases (1814 coronary and 1254 ischemic stroke) were identified. Genetic risk scores (GRSs) were constructed by combining 80 validated genetic variants associated with higher TG and LDL-C or lower HDL-C. The participants’ dietary intake, assessed by a modified diet history method, was ranked according to a diet quality index that included six dietary components: saturated fat, polyunsaturated fat, fish, fiber, fruit and vegetables, and sucrose.

Results

The GRS_LDL-C (P?=?5?×?10^?6) and GRS_HDL-C (P?=?0.02) but not GRS_TG (P?=?0.08) were significantly associated with CVD risk. No significant interaction between the GRSs and diet quality was observed on CVD risk (P?>?0.39). A high compared to a low diet quality attenuated the association between GRS_LDL-C and the risk of incident ischemic stroke (P interaction?=?0.01).

Conclusion

We found some evidence of an interaction between diet quality and GRS_LDL-C on ischemic stroke.

     

The effect of phosphorus binding clay (Phoslock®) in mitigating cyanobacterial nuisance: a laboratory study on the effects on water quality variables and plankton

This laboratory study examined the lanthanum modified clay Phoslock^® for its effectiveness to bind soluble reactive phosphorus (SRP), release of nutrients from this modified clay, its influence on water quality variables (pH, oxygen saturation %, conductivity and turbidity), effects on phytoplankton growth (green alga Scenedesmus obliquus, cyanobacteria Microcystis aeruginosa and Anabaena sp.), and, lastly, its effect on the population growth of the rotifer Brachionus calyciflorus. A clear dose–response for SRP binding by the modified clay was observed. A small amount of ammonium is released from Phoslock^®. We found no effect of Phoslock^® on pH or oxygen saturation. Conductivity increased with the increasing concentration of Phoslock^®. An application of Phoslock^® caused a transient increase of turbidity up to 211 NTU. However, due to rapid settlement, turbidity fell below 13 NTU (~1 m Secchi depth), after 6 h. Phoslock^® addition caused a reduction in growth of all phytoplankton species tested that we attribute to the combined effects of light limitation, flocculation with the bentonite and binding of SRP to Phoslock^®. We estimated the EC₅₀ of Phoslock^® on the population growth of rotifer B. calyciflorus to be 0.15 g Phoslock^® l^?1. Overall, the results of our study indicate Phoslock^® seems to be suitable for field applications.     

Spatial patterns in impacts of fishing on temperate rocky reefs: Are fish abundance and mean size related to proximity to fisher access points?

Effects of fishing on marine communities are becoming increasingly evident, yet little is known of the spatial extent of impacts, particularly for multiple impacts distributed over broad scales. We tested the common perception that commercial and recreational fishing on inshore temperate reefs generate spatial impacts that diminish with distance from fisher access points. We collected data on harvested and non-harvested reef species using underwater visual censuses at 133 shallow rocky reef sites around Tasmania and tested for relationships between assemblage and species level indices of fishing impacts and distance to the nearest boat launching ramp. Slopes of size spectra of fish communities tended to decrease with distance from the nearest boat ramp, with this relationship apparently resulting from low numbers of large fish (> 30 cm TL) and a greater number of smaller fish (< 15 cm TL) at sites closest to access points. At the species level, relationships were evident either in the abundance of legal individuals or the mean size of harvested species with distance to the nearest boat ramp, except for rock lobster. Patterns for rock lobster differed when areas in which commercial or recreational fisheries dominated were considered separately from the statewide analysis. A pattern of increasing numbers of legal lobsters with increasing distance from boat ramps was observed, but only in the areas in which the recreational fishery dominated. Observed relationships in all species were consistent with greater fishing impacts at sites closest to boat ramps, with the exception of exploited wrasses. Banded morwong, which are subject to a live export fishery, appeared to be most affected by proximity to boat ramps. Conversely, no relationships were found between the abundance or size of the most frequently occurring non-harvested species and distance to boat ramps.These results support the hypothesis that greater fishing impacts occur at more accessible sites over the entire Tasmanian coastline. The variability of results among individual species are likely, at least in part, to be related to differences in fisheries characteristics such as vessel size and range, as well as the suitability of our methods for detecting impacts. The potential of such a pattern in fishing impacts to be evident in other locations will thus likely depend on characteristics of the particular fishes and fisheries.     

Mixotrophic cultivation of microalgae to enhance the quality of lipid for biodiesel application: effects of scale of cultivation and light spectrum on reduction of α-linolenic acid

Bioprocess and Biosystems Engineering - The research on microalgal biodiesel is focused not only on getting the highest lipid productivity but also desired quality of lipid. The experiments were...     

Bringing physics to bear on the phenomenon of life: the divergent positions of Bohr, Delbrück, and Schrödinger

The received view on the contributions of the physics community to the birth of molecular biology tends to present the physics community as sharing a basic level consensus on how physics should be brought to bear on biology. I argue, however, that a close examination of the views of three leading physicists involved in the birth of molecular biology, Bohr, Delbrück, and Schr?dinger, suggests that there existed fundamental disagreements on how physics should be employed to solve problems in biology even within the physics community. In particular, I focus on how these three figures differed sharply in their assessment of the relevance of complementarity, the potential of chemical methods, and the relative importance of classical physics. In addition, I assess and develop Roll-Hansen's attempt to conceptualize this history in terms of models of scientific change advanced by Kuhn and Lakatos. Though neither model is fully successful in explaining the divergence of views among these three physicists, I argue that the extent and quality of difference in their views help elucidate and extend some themes that are left opaque in Kuhn's model.     

Impact of changing atmospheric deposition chemistry on carbon and nutrient loading to Ganga River: integrating land–atmosphere–water components to uncover cross-domain carbon linkages

Terrestrial contribution of dissolved organic carbon (DOC) to riverine carbon transport remains relatively uncertain despite recent research highlighting its importance. Here we present data on changing state of atmosphere–land–water transfer and associated shift in DOC build-up in Ganga River (India) for a period of 6 years (March, 2007–February, 2013). Although the N:P stoichiometry of atmospheric deposition (AD) showed a declining trend, there was over 1.4 to 1.6-fold increase in AD-NO₃ ^?, 1.5 to 1.8-fold increase in AD-OC and, over 1.5 to 2.2-fold increase in AD-NH₄ ⁺ and AD-PO₄ ^3? input over time. Water soluble organic carbon and microbial activity in sub-catchments and, DOC and nutrient concentrations in runoff increased consistently over time along the gradient of AD-input. We found a variable but strong linkage between atmospheric deposition and hydrological control of terrestrial carbon and nutrient input to the river. The results showed that the increasing input of AD-nutrients enhance primary production whereas, such input in sub-catchment enhance DOC in runoff and, the coupled effect of these favor DOC build-up in Ganga River at Varanasi. The study that forms the first report establishing trans-boundary drivers of DOC in Ganga River suggests that future climate model should consider large scale inter-regional time series data on changing atmosphere–land–water transfer and associated shift in carbon balance of major rivers for more accurately predicting cross-domain carbon linkages and planning for integrated river basin management.     

Two decades of tropical cyclone impacts on North Carolina’s estuarine carbon,nutrient and phytoplankton dynamics: implications for biogeochemical cycling and water quality in a stormier world

Coastal North Carolina (USA) has experienced 35 tropical cyclones over the past 2 decades; the frequency of these events is expected to continue in the foreseeable future. Individual storms had unique and, at times, significant hydrologic, nutrient-, and carbon (C)-loading impacts on biogeochemical cycling and phytoplankton responses in a large estuarine complex, the Pamlico Sound (PS) and Neuse River Estuary (NRE). Major storms caused up to a doubling of annual nitrogen and tripling of phosphorus loading compared to non-storm years; magnitudes of loading depended on storm tracks, forward speed, and precipitation in NRE-PS watersheds. With regard to C cycling, NRE-PS was a sink for atmospheric CO₂ during dry, storm-free years and a significant source of CO₂ in years with at least one storm, although responses were storm-specific. Hurricane Irene (2011) mobilized large amounts of previously-accumulated terrigenous C in the watershed, mainly as dissolved organic carbon, and extreme winds rapidly released CO₂ to the atmosphere. Historic flooding after Hurricanes Joaquin (2015) and Matthew (2016) provided large inputs of C from the watershed, modifying the annual C balance of NRE-PS and leading to sustained CO₂ efflux for months. Storm type affected biogeochemical responses as C-enriched floodwaters enhanced air–water CO₂ exchange during ‘wet’ storms, while CO₂ fluxes during ‘windy’ storms were largely supported by previously-accumulated C. Nutrient loading and flushing jointly influenced spatio-temporal patterns of phytoplankton biomass and composition. These findings suggest the importance of incorporating freshwater discharge and C dynamics in nutrient management strategies for coastal ecosystems likely to experience a stormier future.     

Spatial and temporal variabilities of δ<Superscript>13</Superscript>C and δ<Superscript>15</Superscript>N within lower trophic levels of a large lake: implications for estimating trophic relationships of consumers

Stable isotopes of carbon (δ¹³C) and nitrogen (δ¹⁵N) often have unique values among lake habitats (e.g. benthic, littoral, pelagic), providing a widely used tool for measuring the structure and energy flow in aquatic food webs. However, there has been little recognition of the spatial and temporal variabilities of these isotopes within habitats of aquatic ecosystems. To address this, δ¹³C and δ¹⁵N were measured in seston, zebra mussels (Dreissena polymorpha) and young-of-year (YOY) yellow (Perca flavescens), and white perch (Morone americana) collected from four sites across the offshore habitat of the western basin of Lake Erie during June–September 2009. Values of δ¹³C and δ¹⁵N showed significant spatial and temporal variations, with month accounting for >50% of the variation, for both stable isotopes and all the species except seston. Such variation in isotope values has the potential to significantly influence or confound interpretation of stable isotopes in measures, such as trophic position (TP) which use lower trophic level organisms as their baseline. For example, TP was found to vary up to 0.7 for yellow and white perch (TP = δ¹⁵N_fish − δ¹⁵N_{zebra mussel}/diet-tissue fractionation factor) depending on the zebra mussel data used (e.g., from a different location or a different collection month). As the use of stable isotopes continues to move from qualitative to more quantitative measures of trophic structure, food web research must recognize the importance of stable isotopes' variability in lower trophic level organisms, especially in large lake systems.     

Biophysical and computational comparison on the binding affinity of three important nutrients to β-lactoglobulin: folic acid,ascorbic acid and vitamin K3

Small globular protein, β-lactoglobulin (βLG), which has significant affinity toward many drugs, is the most abundant whey protein in milk. In this study, the interaction of βLG with three important nutrients, ascorbic acid (ASC), folic acid (FOL), and vitamin K3 (VK3) was investigated by spectroscopic methods (UV–visible and fluorescence) along with molecular docking technique. The results of fluorescence measurements showed that studied nutrients strongly quenched βLG fluorescence in static (FOL and ACS) or static–dynamic combined quenching (VK3) mode. The values of binding constants (K_βLG-ASC ~ 4.34 × 10⁴ M^?1, K_βLG-FOL ~ 1.67 × 10⁴ M^?1and K_βLG-VK3 ~ 13.49 × 10⁴ M^?1 at 310 K) suggested that VK3 and FOL had stronger binding affinity toward βLG than ASC. Thermodynamic analysis indicated that hydrophobic interactions are the major forces in the stability of FOL–βLG complex with enthalpy- and entropy-driving mode while, hydrogen bonds and van der Waals interactions play a major role for βLG–ASC and βLG–VK3 associations. The results of 3D fluorescence FT-IR and UV–Visible measurements indicated that the binding of above nutrients to βLG may induce conformational and micro-environmental changes of protein. Also, there is a reciprocal complement between spectroscopic techniques and molecular docking modeling. The docking results indicate that the ASC, FOL, and VK3 bind to residues located in the subdomain B of βLG. Finally, this report suggests that βLG could be used as an effective carrier of above nutrients in functional foods.     

The influence of water stress on growth,ecophysiology and ornamental quality of potted <Emphasis Type="Italic">Primula vulgaris</Emphasis> ‘Heidy’ plants. New insights to increase water use efficiency in plant production

Efficient irrigation practices are required to reduce the amount of water used. In this study, the effects of different irrigation regimes on changes in growth, ecophysiology and ornamental traits of potted Primula vulgaris ‘Heidy’ plants were investigated. Three experiments were carried out. In the first, the plants were either fully irrigated (100% of container capacity) or not. In the second, plants were watered to full irrigation (control), to 50% of the control (moderate water stress), to 25% of the control (severe water stress), or not irrigated and followed by a rehydration phase. Both experiments were conducted under controlled growth conditions. The third experiment was performed under common nursery conditions in an unheated and shaded greenhouse where plants were either irrigated with common irrigation practices (control), or with 66% of the control amount (moderate water stress), or with 33% of the control (severe water stress). In general, the percentage of senescent plants, the growth index, the number of leaves, and the aerial fresh and the dry weight were not affected by moderate water stress treatments. As expected, increasing water stress resulted in a general decrease in all studied gas exchange parameters. However, stressed plants were more efficient in using water than control plants, suggesting that stomata closed to cope with drought conditions without damaging photosynthesis events. The number of fully opened flowers during the growing season was highest in both control and moderately water stressed plants. In conclusion, moderate, but not severe, water stress could be imposed in P. vulgaris ‘Heidy’ pot production to reduce the water consumption, still maintaining plant ecophysiological performances and ornamental quality.     

Analysis of changes over 44 years in the phytoplankton of Lake Võrtsjärv (Estonia): the effect of nutrients,climate and the investigator on phytoplankton-based water quality indices

We analysed long-term changes in phytoplankton composition in relation to hydrological, meteorological and nutrient loading data in the large (270 km²) shallow (mean depth 2.8 m) Lake Võrtsjärv. Nutrient loads to the lake were heavy in the 1970s and 1980s and decreased considerably thereafter. The average nutrient concentrations for 1985–2004 (1.6 mg l^?1 of total nitrogen and 53 μg l^?1 of total phosphorus) characterize the lake as a eutrophic water body. All four calculated taxonomic indices showed a unidirectional deterioration of the lake’s ecological status, despite reduced concentrations of nutrients. We focused our analysis on the PTSI index, which revealed a stepwise change between the years 1977 and 1979 that coincided with a large increase in water level, but also with a change of investigator. After correcting input data for possible investigator-induced differences, the step change remained because it was caused by major changes in the whole phytoplankton community. The previous dominant Planktolyngbya limnetica was replaced by two species of seasonally altering Limnothrix. Among phytoplankton functional groups, there was a decrease in all groups comprising small-sized phytoplankton species, such as X1, E, F, J, N and an increase in S1 and H1, both represented by filamentous cyanobacteria. Our results suggest a non-linear response of phytoplankton to changing nutrient loadings, and that the change observed between 1977 and 1979 was a regime shift triggered by water level change. High shade tolerance of the new dominants, and their ability to create shade, obviously stabilized the new status making it resistant to restoration efforts.     

Effect of water coordination on competition between π and non-π cation binding sites in aromatic amino acids: l-phenylalanine, l-tyrosine, and l-tryptophan Li+, Na+, and K+ complexes

Quantum chemistry methods have been applied to charged complexes of the alkali metals Li(+), Na(+), and K(+) with the aromatic amino acids (AAAs) phenylalanine (Phe), tyrosine (Tyr), and tryptophan (Trp). The geometries of 72 different complexes (Phe·M, Tyr·M, Trp·M, M is Li(+), Na(+), or K(+)) were completely optimized at the B3LYP/6-311+G(d,p) level of density functional theory. The solvent effect on the geometry and stability of individual complexes was studied by making use of a microsolvation model. The interaction enthalpies, entropies, and Gibbs energies of nine different complexes of the systems Phe·M, Tyr·M, and Trp·M (M is Li(+), Na(+), or K(+)) were also determined at the B3LYP density functional level of theory. The calculated Gibbs binding energies of the M(+)-AAA complexes follow the order Phe < Tyr < Trp for all three metal cations studied. Among the three AAAs studied, the indole ring of Trp is the best π donor for alkali metal cations. Our calculations demonstrated the existence of strong cation-π interactions between the alkali metals and the aromatic side chains of the three AAAs. These AAAs comprise about 8% of all known protein sequences. Thus, besides the potential for hydrogen-bond interaction, aromatic residues of Phe, Tyr, and Trp show great potential for π-donor interactions. The existence of cation-π interaction in proteins has also been demonstrated experimentally. However, more complex experimental studies of metal cation-π interaction in diverse biological systems will no doubt lead to more exact validation of these investigations.     

Effects of UV radiation on five marine microphytobenthic Wadden sea diatoms isolated from the Solthörn tidal flat (Lower Saxony,southern North Sea) – Part I: growth and antioxidative defence strategies

The unconsolidated sediment of intertidal mudflats constitutes a highly unstable environment, due to continuously changing water levels and currents as well as temporary exposure to the air. Therefore, diatoms inhabiting marine intertidal areas are subjected to strongly changing surface light and UV intensities due to exposure at low tide. Five marine intertidal diatoms (Achnanthes exigua, Cocconeis peltoides, Diploneis littoralis, Navicula digitoradiata and Amphora exigua) were isolated from the Solthörn tidal flat (Lower Saxony, southern North Sea). Semi-continuous cultures were used to determine the effect of UV radiation (photosynthetically active radiation only [PAR], PAR+UV-B, PAR+UV-A, PAR+UV-B+UV-A) during short- and long-term exposure (6 h or 30 days). Growth rates, chlorophyll a (chl a), antioxidant capacities, accumulation of phenolic compounds (e.g. flavonoids) and DMSP, and activities of antioxidant enzymes (superoxide dismutase, ascorbate peroxidase, monodehydroascorbate reductase and glutathione reductase) were assessed. UV-A had only minor effects on cells, while growth rate, chl a content and protein content were significantly reduced after long-term UV-B exposure. Achnanthes exigua extracts showed the highest antioxidant capacity. The highest activity of SOD, APX and MDHAR was found under long-term combined UV exposure (PAR+UV-B+UV-A). Overall, the antioxidative defence of the five isolates was stimulated during exposure to UV radiation, as may be found during emersion. Emersion induces oxidative stress and, as a result, growth of the five diatom taxa was inhibited to suit changing environmental conditions. All five taxa tested in the present study showed species-specific acclimatization potentials, providing possible explanations for variability in population, species composition and ecosystem structures in the face of climatic variations.