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2021 ◽  
Vol 13 (24) ◽  
pp. 14049
Author(s):  
Erik Jeppesen ◽  
Liselotte S. Johansson ◽  
Sh Tserenpil ◽  
Martin Søndergaard ◽  
Torben L. Lauridsen ◽  
...  

Cross-latitude studies on lakes have a potential to predict how global warming may cause major changes in phytoplankton biomass and composition, e.g., the development of favourable conditions for cyanobacteria dominance. However, results from these studies may be influenced by biogeographical factors, and the conclusions may, therefore, not hold when considering local response patterns. We used monthly monitoring data from 504 lakes in Denmark—a small and homogeneous geographical region—to establish empirical relationships between key phytoplankton groups and a set of explanatory variables including total phosphorus (TP), total nitrogen (TN), lake mean depth (DEP) and water temperature (TEMP). All variables had strong effects on phytoplankton biomass and composition, but their contributions varied over the seasons, with TEMP being particularly important in June–October. We found dominance of cyanobacteria in terms of biomass and also an increase in dinophytes biomass at higher TEMP, while diatoms and chlorophytes became less important. In May, however, the TEMP effect on total phytoplankton biomass was negative, likely reflecting intensified zooplankton grazing. Our results suggest that biogeographical effects are of minor importance for the response patterns of phytoplankton to temperature and that substantial concentration reductions of TN and TP are needed in eutrophic lakes to counteract the effect of the climate change-induced increase in TEMP.


Atmosphere ◽  
2020 ◽  
Vol 11 (4) ◽  
pp. 399
Author(s):  
Murray Hamilton ◽  
Simon P. Alexander ◽  
Alain Protat ◽  
Steven Siems ◽  
Scott Carpentier

Balloon-borne polarimetric backscatter sonde (polarsonde) observations of aerosol and cloud during the approach of a cold front at Macquarie Island (54.499 S 158.937 E) are described. The polarsonde captures vertical profiles of cloud occurrence and phase. The cloud base and cloud top heights from the backscatter sonde compare favourably with observations made by a co-located cloud radar and ceilometer. An estimate of the total scatter probability from a liquid cloud layer at 1000 m height is used with a Monte Carlo model of the instrument to obtain cloud particle concentration, and this is compared to a measurement of cloud condensation nucleus concentration made at sea level. Backscatter from aerosol, as well as cloud, is significant. A high aerosol loading in part of the pre-frontal airmass is observed at altitudes up to 6 km. Below the melting level, the high cross-polarised return, relative to the co-polarised, indicates a substantial concentration of solid, non-spherical aerosol particles, which due to the high humidity cannot be sea salt or sulphate. A back trajectory analysis indicates that the observed aerosol includes continental dust.


Floorplanning is one of the most critical phases inVLSI circuit design. The module alignment has a substantial concentration on the minimization of chip area and total wirelength in slicing floorplan. At foremost, the disadvantages of dead space are investigated and an instinctive and profligate method is proposed to find the equitable part of component. Then, a tormenting for standardized expression is improved to produce new solution, and the proposed simulated annealing algorithm which improves design efficiency is opted for the best floorplan solution. The proposed MFMW method attains less area on the commonly used AMI33 and AMI 49 benchmark circuits.


Plants ◽  
2019 ◽  
Vol 8 (7) ◽  
pp. 223
Author(s):  
Anjanette DeCarlo ◽  
Stephen Johnson ◽  
Amadé Ouédraogo ◽  
Noura S. Dosoky ◽  
William N. Setzer

Frankincense, the oleogum resin from members of Boswellia, has been used as medicine and incense for thousands of years, and essential oils derived from frankincense are important articles of commerce today. A new source of frankincense resin, Boswellia dalzielii from West Africa has been presented as a new, alternative source of frankincense. In this work, the oleogum resins from 20 different Boswellia dalzielii trees growing in Burkina Faso, West Africa were collected. Hydrodistillation of the resins gave essential oils that were analyzed by GC-MS and GC-FID. The essential oils were dominated by α-pinene (21.0%–56.0%), followed by carvone (2.1%–5.4%) and α-copaene (1.8%–5.0%). Interestingly, there was one individual tree that, although rich in α-pinene (21.0%), also had a substantial concentration of myrcene (19.2%) and α-thujene (9.8%). In conclusion, the oleogum resin essential oil compositions of B. dalzielii, rich in α-pinene, are comparable in composition to other frankincense essential oils, including B. sacra, B. carteri, and B. frereana. Additionally, the differences in composition between samples from Burkina Faso and those from Nigeria are very slight. There is, however, a rare chemotype of B. dalzielii that is dominated by myrcene, found both in Burkina Faso as well as Nigeria.


2018 ◽  
Vol 10 (2) ◽  
pp. 216-231
Author(s):  
Rup Kumar Barman

Since the beginning of the provincial election in the early twentieth century, ‘caste’ has been a ‘political issue’ in India. It transformed into a matter of serious political contradiction when the ‘reservation’ was introduced in India. After the independence of India, in all provincial and parliamentary elections starting from to 1952 till date, organized political parties have further contributed to the ‘process of politicization of caste’. Truly speaking, caste is now a ‘determinant factor’ for formation of the union government. This trend has been equally detected in certain provinces of India especially where the Scheduled Castes (SCs) have substantial concentration. West Bengal, with 21,463,270 SC population (i.e., 23.5% of the state’s population), has been experiencing caste politics since 1952. However, the SCs of this state have been used in electoral politics merely as ‘voters’. They were controlled by the ‘Rights’, till 1962. The period from 1962 to 1976 was a transitional phase from the ‘Rights’ to ‘Lefts’. The ‘Lefts’ established their control over the SCs in 1977. However, re-emergence of the ‘Rights’ (particularly of the All India Trinamool Congress [AITMC]) in 2011 has transformed the SCs as the ‘puppet dancers’ under the direction of the ‘Rights’.


2014 ◽  
Vol 42 (15) ◽  
pp. 9854-9861 ◽  
Author(s):  
Annelyse Thévenin ◽  
Liat Ein-Dor ◽  
Michal Ozery-Flato ◽  
Ron Shamir

Abstract Genomes undergo changes in organization as a result of gene duplications, chromosomal rearrangements and local mutations, among other mechanisms. In contrast to prokaryotes, in which genes of a common function are often organized in operons and reside contiguously along the genome, most eukaryotes show much weaker clustering of genes by function, except for few concrete functional groups. We set out to check systematically if there is a relation between gene function and gene organization in the human genome. We test this question for three types of functional groups: pairs of interacting proteins, complexes and pathways. We find a significant concentration of functional groups both in terms of their distance within the same chromosome and in terms of their dispersal over several chromosomes. Moreover, using Hi-C contact map of the tendency of chromosomal segments to appear close in the 3D space of the nucleus, we show that members of the same functional group that reside on distinct chromosomes tend to co-localize in space. The result holds for all three types of functional groups that we tested. Hence, the human genome shows substantial concentration of functional groups within chromosomes and across chromosomes in space.


2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
Sesan Abiodun Aransiola ◽  
Udeme Joshua Josiah Ijah ◽  
Olabisi Peter Abioye

A study was designed to assess the phytoextraction potential ofGlycine maxL. for lead (Pb). Pots experiment was conducted. Viable seeds were planted in 5 kg of soil placed in each plastic pot having 0 ppm (control), 5 ppm, 10 ppm, 15 ppm, 20 ppm and 25 ppm of Pb respectively. The study was carried out for a period of 12 weeks under natural conditions. Physicochemical properties of the soil were determined using standard methods. The results revealed that pH, phosphorous and moisture contents increased while nitrogen and organic carbon contents decreased in polluted soil remediated withGlycine maxL. compared to the unpolluted soil. Leaf, stem, seeds and roots of the plant were analyzed for Pb uptake after 12 weeks. The plants mopped up substantial concentration of Pb in the above plant biomass of the seeds (4.2 mg/kg), stem (1.37 mg/kg) and leaves (3.37 mg/kg) compared to concentrations in the roots (1.53 mg/kg). The phytoextraction ability of the plant was assessed in terms of its bioconcentration factor (BCF) and translocation factor (TF). It was observed that the levels of Pb in the roots and shoots after 12 weeks showed that more bioavailable pool of Pb was translocated from the root to seeds, leaves and stem in that order. The results obtained suggest that the plant has phytoextraction ability and could be used in restoring soil polluted with Pb.


2012 ◽  
Vol 229-231 ◽  
pp. 183-187
Author(s):  
Nguyen Tien Cuong ◽  
Mohd Ambri Mohamed ◽  
Nobuo Otsuka ◽  
Dam Hieu Chi

The reconstruction and electronic structures of the interfaces between single wall carbon nanotubes and ferromagnetic Co electrodes were studied in the framework of density functional theory. The obtained results revealed that there is a strong interaction between carbon nanotubes and Co electrodes. At the interface region, Top layers of Co surface have been significantly reconstructed. The nature of chemical bonds at the Co-C interface is covalent bonding. The increase of the electron density occurs mainly at the interface where a substantial concentration of electron accumulates in Co-C bonds. A small amount of charge transfer from Co electrode to carbon nanotube junction was found. In addition, the spin polarization of Co atoms at the interface region has been suppressed due to the interaction with a carbon nanotube. It implies that the spin transport through this layer is low, which results in the small hysteretic magneto-resistance of carbon nanotube devices.


Author(s):  
Wei Li ◽  
Cheng Zheng ◽  
Jian Zhao ◽  
Zhengxiang Ning

A novel microwave assisted multi-stage countercurrent extraction (MAMCE) technique was developed for the extraction of dihydromyricetin from Chinese rattan tea, Ampelopsis grossedentata. The technique combined the advantages of microwave heating and dynamic multi-stage countercurrent extraction and achieved marked improvement in extraction efficiency over microwave assisted batch extraction. Analysis of dihydromyricetin concentrations in the solvent and matrix throughout the extraction process showed that by dividing the extraction into multiple stages and exchanging of solvents between stages, steady and substantial concentration gradients were established between the matrix and solvent, thus enabling the achievement of high extraction efficiency. The yield of dihydromyricetin was significantly affected by temperature, pH, solvent/material ratio and extraction time, and optimal extraction conditions were found to be 80-100°C, at acidic pH with a solvent/material ratio of 25-30 to 1 and extraction time of 5-10 min. With the high extraction efficiency and low usage of extraction solvent, MAMCE could prove to be a promising extraction technique which can be applied to the extraction of dihydromyricentin and other bioactive substances from natural materials.


2011 ◽  
Vol 2 (1) ◽  
pp. ar.2011.2.0005 ◽  
Author(s):  
Rashmi Sharma ◽  
Ravi Deval ◽  
Vikash Priyadarshi ◽  
Shailendra N. Gaur ◽  
Ved P. Singh ◽  
...  

Allergy to fungi has been linked to a wide range of illnesses, including rhinitis and asthma. Therefore, exposure to fungi in home environment is an important factor for fungal allergy. The present study was aimed to investigate types of airborne fungi inside and outside the homes of asthmatic children and control subjects (nonasthmatic children). The dominant fungi were evaluated for their quantitative distribution and seasonal variation. The air samples were collected from indoors and immediate outdoors of 77 selected homes of children suffering from bronchial asthma/allergic rhinitis using Andersen volumetric air sampler. The isolated fungal genera/species were identified using reference literature, and statistical analysis of the dominant fungi was performed to study the difference in fungal concentration between indoor and immediate outdoor sites as well as in between different seasons. A total of 4423 air samples were collected from two indoor and immediate outdoor sites in a 1-year survey of 77 homes. This resulted in the isolation of an average of 110,091 and 107,070 fungal colonies per metric cube of air from indoor and outdoor sites, respectively. A total of 68 different molds were identified. Different species of Aspergillus, Alternaria, Cladosporium, and Penicillium were found to be the most prevalent fungi in Delhi homes, which constituted 88.6% of the total colonies indoors. Highest concentration was registered in autumn and winter months. Total as well as dominant fungi displayed statistically significant differences among the four seasons (p < 0.001). The largest number of isolations were the species of Aspergillus ( >40% to total colony-forming units in indoors as well as outdoors) followed by Cladosporium spp. Annual concentration of Aspergillus spp. was significantly higher (p < 0.05) inside the homes when compared with outdoors. Most of the fungi also occurred at a significantly higher (p < 0.001) rate inside the homes when compared with immediate outdoors. Asthmatic children in Delhi are exposed to a substantial concentration of mold inside their homes as well as immediate outdoor air. The considerable seasonal distributions of fungi provide valuable data for investigation of the role of fungal exposure as a risk for respiratory disorders among patients suffering from allergy or asthma in Delhi.


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