Impact of Effective Light Climate on Periphyton in the Nutrient Impacted River Ganges

2016 ◽  
Vol 2 (1 and 2) ◽  
pp. 59-68
Author(s):  
Usha Pandey ◽  
Jitendra Pandey
Keyword(s):  
Large Fraction ◽  
Light Attenuation ◽  
Standing Stock ◽  
Secchi Depth ◽  
Organic Load ◽  
Light Climate ◽  
Regulated Rivers ◽  
Periphyton Biomass ◽  
Assimilation Capacity ◽  
The Impact

Anthropogenic releases in large regulated rivers are overriding their organic load assimilation capacity and ability to rejuvenate. Effective light penetration in such water bodies are constrained by trade-off between organic load and benthic oxygen supply.We investigated the impact of light climate, as influenced by dissolved organic carbon (DOC) and phytoplankton shading effect, on periphyton biomass accrual in Ganges during summer low flows. Periphyton chlorophyll a decreased with increasing growth of phytoplankton and DOC. Periphyton biomass showed significant negative correlation with DOC (R2=0.9483; p less than 0.0001) and phytoplankton biomass (R2=0.9251; p less than 0.0001) and positive correlation with Secchi depth (R2=0.9506; p less than 0.0001). Among taxonomic divisions, Chlorophyta, with 24-60% of total standing stock, showed higher biomass at sites characterized by moderate nutrients and DOC levels. Cyanophyta (39-74%) contributed large fraction at eutrophic sites and Bacillariophyta (2-5%) at moderately eutrophic sites. Cyanophycean alga Phormidium appeared dominant at sites enriched in nutrients. The study indicated that light attenuation driven by DOC and phytoplankton is leading to erode benthic primary producers and redistribution of taxonomic divisions in Ganges, which may, by implication, entail a similar shift in the trophic cascades.

scholarly journals Size-resolved characterization of organic aerosol in the North China Plain: new insights from high resolution spectral analysis

2021 ◽  
Author(s):  
Weiqi Xu ◽  
Chun Chen ◽  
Yanmei Qiu ◽  
Conghui Xie ◽  
Yunle Chen ◽  
...  
Keyword(s):  
Radiative Forcing ◽  
North China Plain ◽  
North China ◽  
Fine Particles ◽  
Large Fraction ◽  
Organic Aerosol ◽  
Size Distributions ◽  
The North ◽  
The Impact

Organic aerosol (OA), a large fraction of fine particles, has a large impact on climate radiative forcing and human health, and the impact depends strongly on size distributions. Here we...

scholarly journals Citizen Science Tools Reveal Changes in Estuarine Water Quality Following Demolition of Buildings

2021 ◽  
Vol 13 (9) ◽  
pp. 1683
Author(s):  
Nandini Menon ◽  
Grinson George ◽  
Rajamohananpillai Ranith ◽  
Velakandy Sajin ◽  
Shreya Murali ◽  
...  
Keyword(s):  
Water Quality ◽  
Dissolved Oxygen ◽  
Citizen Science ◽  
Secchi Depth ◽  
Lake Water Quality ◽  
Demolition Waste ◽  
Water Colour ◽  
Water Quality Variables ◽  
The Impact

Turbidity and water colour are two easily measurable properties used to monitor pollution. Here, we highlight the utility of a low-cost device—3D printed, hand-held Mini Secchi disk (3DMSD) with Forel-Ule (FU) colour scale sticker on its outer casing—in combination with a mobile phone application (‘TurbAqua’) that was provided to laymen for assessing the water quality of a shallow lake region after demolition of four high-rise buildings on the shores of the lake. The demolition of the buildings in January 2020 on the banks of a tropical estuary—Vembanad Lake (a Ramsar site) in southern India—for violation of Indian Coastal Regulation Zone norms created public uproar, owing to the consequences of subsequent air and water pollution. Measurements of Secchi depth and water colour using the 3DMSD along with measurements of other important water quality variables such as temperature, salinity, pH, and dissolved oxygen (DO) using portable instruments were taken for a duration of five weeks after the demolition to assess the changes in water quality. Paired t-test analyses of variations in water quality variables between the second week of demolition and consecutive weeks up to the fifth week showed that there were significant increases in pH, dissolved oxygen, and Secchi depth over time, i.e., the impact of demolition waste on the Vembanad Lake water quality was found to be relatively short-lived, with water clarity, colour, and DO returning to levels typical of that period of year within 4–5 weeks. With increasing duration after demolition, there was a general decrease in the FU colour index to 17 at most stations, but it did not drop to 15 or below, i.e., towards green or blue colour indicating clearer waters, during the sampling period. There was no significant change in salinity from the second week to the fifth week after demolition, suggesting little influence of other factors (e.g., precipitation or changes in tidal currents) on the inferred impact of demolition waste. Comparison with pre-demolition conditions in the previous year (2019) showed that the relative changes in DO, Secchi depth, and pH were very high in 2020, clearly depicting the impact of demolition waste on the water quality of the lake. Match-ups of the turbidity of the water column immediately before and after the demolition using Sentinel 2 data were in good agreement with the in situ data collected. Our study highlights the power of citizen science tools in monitoring lakes and managing water resources and articulates how these activities provide support to Sustainable Development Goal (SDG) targets on Health (Goal 3), Water quality (Goal 6), and Life under the water (Goal 14).

scholarly journals Nonsynonymous single nucleotide polymorphisms of NHE3 differentially decrease NHE3 transporter activity

2015 ◽  
Vol 308 (9) ◽  
pp. C758-C766 ◽  
Author(s):  
Xinjun Cindy Zhu ◽  
Rafiquel Sarker ◽  
John R. Horton ◽  
Molee Chakraborty ◽  
Tian-E Chen ◽  
...  
Keyword(s):  
Single Nucleotide Polymorphisms ◽  
Large Fraction ◽  
Regulatory Protein ◽  
Nucleotide Polymorphisms ◽  
Genetic Determinants ◽  
Single Nucleotide ◽  
Mutant Proteins ◽  
Homologous Protein ◽  
Genetic Abnormalities ◽  
The Impact

Genetic determinants appear to play a role in susceptibility to chronic diarrhea, but the genetic abnormalities involved have only been identified in a few conditions. The Na+/H+ exchanger 3 (NHE3) accounts for a large fraction of physiologic intestinal Na+ absorption. It is highly regulated through effects on its intracellular COOH-terminal regulatory domain. The impact of genetic variation in the NHE3 gene, such as single nucleotide polymorphisms (SNPs), on transporter activity remains unexplored. From a total of 458 SNPs identified in the entire NHE3 gene, we identified three nonsynonymous mutations (R474Q, V567M, and R799C), which were all in the protein's intracellular COOH-terminal domain. Here we evaluated whether these SNPs affect NHE3 activity by expressing them in a mammalian cell line that is null for all plasma membrane NHEs. These variants significantly reduced basal NHE3 transporter activity through a reduction in intrinsic NHE3 function in variant R474Q, abnormal trafficking in variant V567M, or defects in both intrinsic NHE3 function and trafficking in variant R799C. In addition, variants NHE3 R474Q and R799C failed to respond to acute dexamethasone stimulation, suggesting cells with these mutant proteins might be defective in NHE3 function during postprandial stimulation and perhaps under stressful conditions. Finally, variant R474Q was shown to exhibit an aberrant interaction with calcineurin B homologous protein (CHP), an NHE3 regulatory protein required for basal NHE3 activity. Taken together, these results demonstrate decreased transport activity in three SNPs of NHE3 and provide mechanistic insight into how these SNPs impact NHE3 function.

scholarly journals Binary asteroid (31) Euphrosyne: ice-rich and nearly spherical

2020 ◽  
Vol 641 ◽  
pp. A80
Author(s):  
B. Yang ◽  
J. Hanuš ◽  
B. Carry ◽  
P. Vernazza ◽  
M. Brož ◽  
...  
Keyword(s):  
Adaptive Optics ◽  
Family Formation ◽  
Large Fraction ◽  
Imaging Study ◽  
Spherical Shape ◽  
Hydrostatic Equilibrium ◽  
Main Belt ◽  
Binary Asteroid ◽  
Water Ice ◽  
The Impact

Aims. Asteroid (31) Euphrosyne is one of the biggest objects in the asteroid main belt and it is also the largest member of its namesake family. The Euphrosyne family occupies a highly inclined region in the outer main belt and contains a remarkably large number of members, which is interpreted as an outcome of a disruptive cratering event. Methods. The goals of this adaptive-optics imaging study are threefold: to characterize the shape of Euphrosyne, to constrain its density, and to search for the large craters that may be associated with the family formation event. Results. We obtained disk-resolved images of Euphrosyne using SPHERE/ZIMPOL at the ESO 8.2 m VLT as part of our large program (ID: 199.C-0074, PI: Vernazza). We reconstructed its 3D shape via the ADAM shape modeling algorithm based on the SPHERE images and the available light curves of this asteroid. We analyzed the dynamics of the satellite with the Genoid meta-heuristic algorithm. Finally, we studied the shape of Euphrosyne using hydrostatic equilibrium models. Conclusions. Our SPHERE observations show that Euphrosyne has a nearly spherical shape with the sphericity index of 0.9888 and its surface lacks large impact craters. Euphrosyne’s diameter is 268 ± 6 km, making it one of the top ten largest main belt asteroids. We detected a satellite of Euphrosyne – S/2019 (31) 1 – that is about 4 km across, on a circular orbit. The mass determined from the orbit of the satellite together with the volume computed from the shape model imply a density of 1665 ± 242 kg m−3, suggesting that Euphrosyne probably contains a large fraction of water ice in its interior. We find that the spherical shape of Euphrosyne is a result of the reaccumulation process following the impact, as in the case of (10) Hygiea. However, our shape analysis reveals that, contrary to Hygiea, the axis ratios of Euphrosyne significantly differ from those suggested by fluid hydrostatic equilibrium following reaccumulation.

scholarly journals Impact of extreme drought and incentive programs on flooded agriculture and wetlands in California’s Central Valley

2018 ◽  
Author(s):  
Matthew E Reiter ◽  
Nathan Elliott ◽  
Dennis Jongsomjit ◽  
Gregory H Golet ◽  
Mark D Reynolds
Keyword(s):  
Surface Water ◽  
Large Fraction ◽  
Central Valley ◽  
Open Water ◽  
Extreme Drought ◽  
Freshwater Wetland ◽  
Post Harvest ◽  
Incentive Programs ◽  
Managed Wetlands ◽  
The Impact

Between 2013 and 2015 a large part of the western United States, including the Central Valley of California, sustained an extreme drought. The Central Valley is recognized as a region of hemispheric importance for waterbirds which use flooded agriculture and wetlands as habitat. Thus, the impact of drought on the distribution of surface water needed to be assessed to understand the effects on waterbird habitat availability. We used satellites to quantify the impact the recent extreme drought on the timing and extent of available waterbird habitat during the non-breeding season (July – May) by examining flooding in agriculture (rice, corn, and other crops) and managed wetlands across the Central Valley. We assessed the influence of habitat incentive programs, particularly The Nature Conservancy’s BirdReturns and the Natural Resources Conservation Service’s Waterbird Habitat Enhancement Program (WHEP), at offsetting waterbird habitat loss related to drought. Overall, we found significant declines in open water in post-harvest agriculture (20 – 80% declines) and in managed wetlands (47 – 59% declines) during the 2013 – 2015 drought compared to non-drought years 2000 – 2011. Crops associated with the San Joaquin Valley, specifically corn, as well as wetlands in that part of the Central Valley exhibited larger reductions in open water than rice and wetlands in the Sacramento Valley. However, seasonal wetlands on protected lands had a marginally significant (P<0.10) higher amount of open water in the drought years than those on non-protected lands. A large fraction of the daily open water in rice during certain times of the year, particularly in the fall for BirdReturns (64%) and the winter for WHEP (100%), may have been provided through incentive programs underscoring the contribution of these programs. However, further assessment is needed to know how much the incentive programs directly offset the impact of drought in post-harvest rice or simply supplemented funding for activities that might have been done regardless. Our, first of its kind, landscape analysis documents the significant impacts of the drought on freshwater wetland habitats in the Central Valley and highlights the value of using satellite data to track surface water and waterbird habitats. More research is needed to understand subsequent impacts on the freshwater dependent species that rely on these systems and how incentive programs can most strategically support vulnerable species during future drought.

The Impact of Military Spending on Economic Development

2018 ◽  
pp. 182-191
Author(s):  
Saptarshi Chakraborty
Keyword(s):  
Economic Growth ◽  
Causal Effect ◽  
Large Fraction ◽  
Military Spending ◽  
Military Expenditure ◽  
Policy Debate ◽  
External Threats ◽  
The Cost ◽  
The Military ◽  
The Impact

Some countries spend a relatively large percentage of GDP on their militaries in order to preserve or secure their status as global powers. Others do so because they are ruled by military governments or aggressive regimes that pose a military threat to their neighbors or their own populations. It is debatable whether there is a causal relationship between military spending and economic growth in the economy. It is again a policy debate how much to allocate funds for civilian and how much for military expenditure. Under these puzzling results of the impact of military expenditure on economic growth which is frequently found to be non-significant or negative, yet most countries spend a large fraction of their GDP on defense and the military. The chapter tries to investigate the relationship between military spending and economic growth in India. It also sees whether external threats, corruption, and other relevant controls have any causal effect. This chapter obtains that additional expenditure on Indian military in the presence of additional threat is significantly detrimental to growth implying that India cannot afford to fight or demonstrate power at the cost of its development.

scholarly journals O12 Circulating concentrations of broad-spectrum beta-lactams in children with cancer: beware of glomerular hyperfiltration!

2019 ◽  
Vol 104 (6) ◽  
pp. e5.2-e6
Author(s):  
P André ◽  
L Diezi ◽  
LA Decosterd ◽  
PA Crisinel ◽  
K Dao ◽  
...  
Keyword(s):  
Febrile Neutropenia ◽  
Broad Spectrum ◽  
Large Fraction ◽  
Glomerular Hyperfiltration ◽  
List Type ◽  
Beta Lactams ◽  
Children With Cancer ◽  
Therapeutic Success ◽  
The Impact ◽  
Trough Levels

BackgroundBroad-spectrum beta-lactams such as meropenem (MER) and piperacillin-tazobactam (PIP) are commonly prescribed in children with cancer having febrile neutropenia. They are introduced at intensive dosage, unless decreased renal function calls for dose reduction. Recently, glomerular hyperfiltration (HF) was recognized to be frequent among children with cancer during initial cycles of chemotherapy.1 We evaluated the impact of HF on therapeutic exposure to MER and PIP.MethodsWe retrieved retrospectively all MER and PIP plasma levels measured in children with cancer in our hospital between 2012 and 2018. We compared trough levels with usual therapeutic ranges (derived from reference values of minimum inhibitory concentrations). We classified the children according to plasma creatinine and estimated glomerular filtration rate (Schwartz formula) as either altered-normal (< 160 mL/min/1.73 m2) or increased (i.e. HF, ≥160). Neutropenia was defined as absolute neutrophil count < 500 cells/µL.ResultsWe collected 120 concentration values (53 MER, 67 PIP) measured in 50 children with cancer. Among them, 74 (62%) had concomitant creatinine values suggestive of HF, and 80 (67%) were neutropenic. Overall, 67% of trough levels were below usual therapeutic ranges (MER: 2–8 mg/L, PIP 8–30 mg/L). This was more often the case in presence of concomitant HF (MER: 92%, PIP: 83%), often associated with neutropenia. Low exposure was observed not only at initial intensive dosage (MER: 120 mg/kg/day, PIP: 400 mg/kg/day)2 but tended to persist despite dosage readjustment based on concentration monitoring. Moreover, bacteremia was diagnosed in 38 cases.ConclusionCurrent recommended doses of MER and PIP do not provide optimal concentration coverage throughout the dosing interval in a large fraction of children with cancer and febrile neutropenia as a result of HF. Monitoring of beta-lactams should be offered to all children with cancer to ensure best therapeutic success and avoid the development of resistance.ReferencesKwatra NS, Meany HJ, Ghelani SJ, Zahavi D, Pandya N, Majd M. Glomerular hyperfiltration in children with cancer: prevalence and a hypothesis. Pediatr Radiol 2017;47(2):221–226.The Lexicomp Pediatric & Neonatal Dosage Handbook, 21st edition, Lexicomp, USA.Disclosure(s)Nothing to disclose

Cache Leakage Reduction Techniques for Hybrid SPM-Cache Architectures

2020 ◽  
pp. 2150008
Author(s):  
Hao Wen ◽  
Wei Zhang
Keyword(s):  
Large Fraction ◽  
Hybrid Architecture ◽  
Total Energy Consumption ◽  
Access Frequency ◽  
Reduction Techniques ◽  
Cache Architecture ◽  
Scratch Pad Memory ◽  
Significant Performance ◽  
Power Mode ◽  
The Impact

Leakage energy has become an increasingly large fraction of total energy consumption, making it important to reduce leakage energy for improving the overall energy efficiency for embedded processors. In this paper, we explore how to reduce the cache leakage energy efficiently in a hybrid Scratch-Pad Memory (SPM) and cache architecture. Different from stand-alone cache, since the frequently used data may be allocated to the SPM for rapid retrieval in the hybrid architecture, the access frequency to the cache is reduced. It is possible to place the cache lines of the hybrid SPM-cache into the low power mode more aggressively than traditional leakage management for regular caches, which can reduce more leakage energy without significant performance degradation. Also, we propose a Hybrid Drowsy-Gated VDD (HDG) technique, which can adaptively exploit both short and long idle intervals of cache accesses to minimize leakage energy with insignificant performance overhead. In addition, we discussed the impact of cache size on the idle intervals of accesses, which will affect the efficiency of leakage management methods that exploit the idle intervals to reduce leakage energy.

scholarly journals Prediction of source contributions to urban background PM<sub>10</sub> concentrations in European cities: a case study for an episode in December 2016 using EMEP/MSC-W rv4.15 and LOTOS-EUROS v2.0 – Part 1: The country contributions

2020 ◽  
Vol 13 (4) ◽  
pp. 1787-1807 ◽  
Author(s):  
Matthieu Pommier ◽  
Hilde Fagerli ◽  
Michael Schulz ◽  
Alvaro Valdebenito ◽  
Richard Kranenburg ◽  
...  
Keyword(s):  
Particulate Matter ◽  
Emission Reduction ◽  
Total Concentration ◽  
Large Fraction ◽  
Mitigation Strategies ◽  
Grid Cells ◽  
Source Attribution ◽  
European Cities ◽  
Guideline Value ◽  
The Impact

Abstract. A large fraction of the urban population in Europe is exposed to particulate matter levels above the WHO guideline value. To make more effective mitigation strategies, it is important to understand the influence on particulate matter (PM) from pollutants emitted in different European nations. In this study, we evaluate a country source contribution forecasting system aimed at assessing the domestic and transboundary contributions to PM in major European cities for an episode in December 2016. The system is composed of two models (EMEP/MSC-W rv4.15 and LOTOS-EUROS v2.0), which allows the consideration of differences in the source attribution. We also compared the PM10 concentrations, and both models present satisfactory agreement in the 4 d forecasts of the surface concentrations, since the hourly concentrations can be highly correlated with in situ observations. The correlation coefficients reach values of up to 0.58 for LOTOS-EUROS and 0.50 for EMEP for the urban stations; the values are 0.58 for LOTOS-EUROS and 0.72 for EMEP for the rural stations. However, the models underpredict the highest hourly concentrations measured by the urban stations (mean underestimation of 36 %), which is to be expected given the relatively coarse model resolution used (0.25∘ longitude × 0.125∘ latitude). For the source attribution calculations, LOTOS-EUROS uses a labelling technique, while the EMEP/MSC-W model uses a scenario having reduced anthropogenic emissions, and then it is compared to a reference run where no changes are applied. Different percentages (5 %, 15 %, and 50 %) for the reduced emissions in the EMEP/MSC-W model were used to test the robustness of the methodology. The impact of the different ways to define the urban area for the studied cities was also investigated (i.e. one model grid cell, nine grid cells, and grid cells covering the definition given by the Global Administrative Areas – GADM). We found that the combination of a 15 % emission reduction and a larger domain (nine grid cells or GADM) helps to preserve the linearity between emission and concentrations changes. The nonlinearity, related to the emission reduction scenario used, is suggested by the nature of the mismatch between the total concentration and the sum of the concentrations from different calculated sources. Even limited, this nonlinearity is observed in the NO3-, NH4+, and H2O concentrations, which is related to gas–aerosol partitioning of the species. The use of a 15 % emission reduction and of a larger city domain also causes better agreement on the determination of the main country contributors between both country source calculations. Over the 34 European cities investigated, PM10 was dominated by domestic emissions for the studied episode (1–9 December 2016). The two models generally agree on the dominant external country contributor (68 % on an hourly basis) to PM10 concentrations. Overall, 75 % of the hourly predicted PM10 concentrations of both models have the same top five main country contributors. Better agreement on the dominant country contributor for primary (emitted) species (70 % is found for primary organic matter (POM) and 80 % for elemental carbon – EC) than for the inorganic secondary component of the aerosol (50 %), which is predictable due to the conceptual differences in the source attribution used by both models. The country contribution calculated by the scenario approach depends on the chemical regime, which largely impacts the secondary components, unlike the calculation using the labelling approach.

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