scholarly journals To What Degree Can the Specifics of Occurrence of Glacial Relic Betula humilis Schrank Be an Indicator of Habitat Conditions of Moderate Climate Peatlands?

Water ◽  
2018 ◽  
Vol 10 (8) ◽  
pp. 1062 ◽  
Author(s):  
Artur Serafin ◽  
Danuta Urban ◽  
Urszula Bronowicka-Mielniczuk ◽  
Agnieszka Szczurowska
Keyword(s):  
Habitat Conditions ◽  
Climate Conditions ◽  
Factors Affecting ◽  
Habitat Transformation ◽  
Ph Values ◽  
Study Results ◽  
Botanical Research ◽  
Betula Humilis ◽  
Physical And Chemical ◽  
Moderate Climate

Anthropogenic transformations of habitat conditions in moderate climate peatlands frequently cause a decrease in the number of sites of occurrence and the size of the population of many valuable plant species, including the boreal relic Betula humilis. The objective of this paper was an attempt to relate the specifics of the occurrence of the glacial relic Betula humilis in the peatlands of Central-Eastern Poland, which developed under moderate climate conditions, to the conditions of the natural environment identified through research into the physical and chemical parameters of the groundwater, as well as botanical research into its habitat. The study results confirm that shrub birch has a broad range of ecological tolerance to the majority of the studied factors and can therefore be an indicator of habitat transformation. Important environmental factors affecting its abundance are water relations and the contribution of calcium hydroxide and phosphorus fractions. A condition favouring the proper functioning of individuals of the studied species is TP values lower than other obtained values, in the following range: 0.08–0.32; P-PO4: 0.1; TN: 2.2–21.2; N-NH4: 0.1–0.46; DOC: 24.6–55.9 (mg·dm−3), as well as higher than average pH values, in the following range: 5.34–5.95; Ca: 5.67–28.1; Mg: 0.56–2.41 (mg·dm−3) and EC: 72.1–142.3 (µS·cm−1).

scholarly journals Factors Affecting the Setting Time of Fly Ash-Based Geopolymer

2016 ◽  
Vol 841 ◽  
pp. 90-97 ◽  
Author(s):  
Antoni ◽  
Stephen Wibiatma Wijaya ◽  
Djwantoro Hardjito
Keyword(s):  
Fly Ash ◽  
Initial Temperature ◽  
Ph Value ◽  
Setting Time ◽  
Chemical Properties ◽  
Curing Temperature ◽  
Factors Affecting ◽  
Ph Values ◽  
Physical And Chemical ◽  
And Chemical Properties

Fly ash is a waste from coal burning, that are generated with fluctuation both in its physical and chemical characteristics. This characteristics of fly ash when used in the making of geopolymer concrete will greatly affect the final products obtained. The pH value measured in fly ash, according previous research, can influence the setting time of geopolymer and fly ash with high pH values can cause flash-setting in the concrete. Understanding more clearly about the factors that affect the setting time of fly ash based geopolymer is important for further progress and development of the material. It was found that factors that influence the setting time of geopolymer was not only from the physical and chemical properties of the fly ash itself. Other factors such as composition and mix design, manufacturing process and environmental conditions can also affect its setting time. The experimental results showed that fly ash particle size, CaO and MgO content, in addition to ratio of sodium silicate and sodium hydroxide in the alkali solution, molarity of NaOH, initial temperature of the mixture, curing temperature, and mix volume could potentially influence the setting time of the geopolymer mixture.

scholarly journals Some clastic rocks as parent rocks in beech forests of Brezovica - Juzni Kucaj

2003 ◽  
pp. 129-138
Author(s):  
Vesna Joksimovic ◽  
Bojan Gajic
Keyword(s):  
Plant Nutrition ◽  
Sedimentary Rocks ◽  
Beech Forests ◽  
Climate Conditions ◽  
Factors Affecting ◽  
Clastic Rocks ◽  
Study Results ◽  
Different Types ◽  
Parent Rocks ◽  
Soil Quality Improvement

On the large forest areas, where the measures of soil quality improvement are absent or rarely undertaken, the rocks are the sources of a great number of elements in plant nutrition and one of the factors affecting the contents of some elements in plants. The aim of the study is to determine the differences in the contents of Cu, Zn, Mn, Ni, Fe, Cd, Co, Pb and Cr in the beech leaves developed in the same climate conditions, on morphologically similar terrains, composed of different types of sedimentary rocks. This paper presents the study results of the contents of the above elements in argillites, sandstones (grauwackes) and microconglomerates occurring as the parent rocks in high beech forests in the region of GJ Bogovina (Brezovica Juzni Kucaj and in the leaves of beech developed on these rocks.

Physical and Chemical Characteristics of Meats of the Indonesian Indigenous Crossbred Chickens Fed Fermented Mixture of Papaya (Carica papaya L.) Leaf and Seed Meal

2020 ◽  
Keyword(s):  
Crude Protein ◽  
Control Diet ◽  
Dietary Treatment ◽  
Seed Meal ◽  
Chemical Characteristics ◽  
Breast Meat ◽  
Ph Values ◽  
Physical And Chemical Characteristics ◽  
Dietary Treatments ◽  
Physical And Chemical

The objective of this present study was to investigate the effect of feeding fermented mixture of papaya leaf and seed meal (FERM) on the physical and chemical characteristics of meats of the Indonesian indigenous crossbred chicken (IICC). The study was carried out with 300 day-old IICC. The chicks were randomly distributed to five treatment groups, i.e., CONT (control diet based on corn-soybean- diet), FERMA (diet containing 1% FERM), FERMB (2.5% FERM), FERMC (5% FERM) and FERMD (7.5% FERM). Each treatment group consisted of 6 replicates with 10 IICC in each. At week 8, one chick from each replicate was randomly taken and slaughtered. After being de-feathered and eviscerated, samples from breast and thigh meats were obtained. Results showed that the increased levels of FERM was followed by the increased (P<0.05) pH values, moisture and crude protein content of breast meats of the IICC. Dietary incorporation of FERM especially at the level of 2.5% increased (P<0.05) the content of fat in the breast meat of IICC, while further increased levels of FERM did not alter (P>0.05) the fat content of the IICC breast meat. Dietary treatment did not have any effect (P>0.05) on the lightness (L*) values of breast meat of the IICC. The redness (a*) values were higher (P<0.05) in FERMD breast meat than other. FERM diet resulted in lower (P<0.05) yellowness (b*) values in the IICC breast meat. The pH values and moisture content of thigh meat increased (P<0.05) with the increased level of FERM. The WHC decreased (P<0.05) with the elevated levels of FERM in the diets. There was an increase (P<0.05) in crude protein concentration in FERMA as compared to the other meats. Crude fat and ash concentrations in thigh meat were affected (P<0.05) by the treatments. Dietary treatments had no impact (P>0.05) on L* values of thigh meats. Feeding FERM at 7.5% from diets increased (P<0.05) and decreased (P<0.05) the redness and yellowness of meats. In conclusion, dietary inclusion of FERM especially at the level of 7.5% from diets improved the physical and chemical characteristics of the IICC meats.

scholarly journals A Quantitative Analysis of Factors Influencing Organic Matter Concentration in the Topsoil of Black Soil in Northeast China Based on Spatial Heterogeneous Patterns

2021 ◽  
Vol 10 (5) ◽  
pp. 348
Author(s):  
Zhenbo Du ◽  
Bingbo Gao ◽  
Cong Ou ◽  
Zhenrong Du ◽  
Jianyu Yang ◽  
...  
Keyword(s):  
Land Use ◽  
Organic Matter ◽  
Soil Erosion ◽  
Soil Type ◽  
Northeast China ◽  
Black Soil ◽  
Factors Affecting ◽  
Soil Zone ◽  
Rainfed Farming ◽  
Study Results

Black soil is fertile, abundant with organic matter (OM) and is exceptional for farming. The black soil zone in northeast China is the third-largest black soil zone globally and produces a quarter of China’s commodity grain. However, the soil organic matter (SOM) in this zone is declining, and the quality of cultivated land is falling off rapidly due to overexploitation and unsustainable management practices. To help develop an integrated protection strategy for black soil, this study aimed to identify the primary factors contributing to SOM degradation. The geographic detector, which can detect both linear and nonlinear relationships and the interactions based on spatial heterogeneous patterns, was used to quantitatively analyze the natural and anthropogenic factors affecting SOM concentration in northeast China. In descending order, the nine factors affecting SOM are temperature, gross domestic product (GDP), elevation, population, soil type, precipitation, soil erosion, land use, and geomorphology. The influence of all factors is significant, and the interaction of any two factors enhances their impact. The SOM concentration decreases with increased temperature, population, soil erosion, elevation and terrain undulation. SOM rises with increased precipitation, initially decreases with increasing GDP but then increases, and varies by soil type and land use. Conclusions about detailed impacts are presented in this paper. For example, wind erosion has a more significant effect than water erosion, and irrigated land has a lower SOM content than dry land. Based on the study results, protection measures, including conservation tillage, farmland shelterbelts, cross-slope ridges, terraces, and rainfed farming are recommended. The conversion of high-quality farmland to non-farm uses should be prohibited.

scholarly journals Stimulation of mitochondrial calcium ion efflux by thiol-specific reagents and by thyroxine. The relationship to adenosine diphosphate retention and to mitochondrial permeability

1979 ◽  
Vol 182 (2) ◽  
pp. 455-464 ◽  
Author(s):  
E J Harris ◽  
M Al-Shaikhaly ◽  
H Baum
Keyword(s):  
Thyroid Hormones ◽  
Calcium Ion ◽  
Adenine Nucleotides ◽  
Adenosine Diphosphate ◽  
Ruthenium Red ◽  
Reduced Form ◽  
Factors Affecting ◽  
Ph Values ◽  
Rat Heart Mitochondria ◽  
The Relationship

Respiring rat heart mitochondria were loaded with Ca2+ and then treated with Ruthenium Red. The factors affecting the subsequent Ca2+-efflux were studied. Addition of rotenone or antimycin led to a decline of efflux except at pH values above 7.2, provided the load was less than about 80 nmol per mg of protein. Oligomycin reversed the effect of the respiratory inhibitors. Independently of respiration, efflux was stimulated by the uncoupler trifluoromethyltetrachlorbenzimadazole, by mersalyl and by thyroid hormones. The stimulated efflux could be diminished by ADP, with Mg2+ as cofactor if efflux was rapid. With respiration in progress, efflux could be stimulated by N-ethylmaleimide and 5,5′-dithiobis-(2-nitrobenzoate). The effects of mersalyl and of thyroid hormones could be diminished with dithiothreitol. In the absence of stimulating agents, the Ca2+ efflux was proportional to the load up to some critical amount, this critical amount was decreased by the agents. Thyroxine and mersalyl caused not only loss of Ca2+, but also simultaneous, but not necessarily proportional, loss of internal adenine nucleotides. Both efflux rates were kept at a low value by bongkrekic acid added before the stimulating agent. It is concluded that Ca2+ efflux is a measure of a permeability controlled by the binding of ADP (an Mg2+) to the inner membrane, and that this in turn depends on the maintenance of certain thiol gropus in a reduced form by a reaction that uses NADH and ATP and the energy-linked transhydrogenase.

scholarly journals Hybrid Acrylated Chitosan and Thiolated Pectin Cross-Linked Hydrogels with Tunable Properties

Polymers ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 266
Author(s):  
Shaked Eliyahu ◽  
Alexandra Galitsky ◽  
Esther Ritov ◽  
Havazelet Bianco-Peled
Keyword(s):  
Electrostatic Interactions ◽  
Profile Analysis ◽  
Hybrid Hydrogel ◽  
Texture Profile ◽  
Ph Values ◽  
X Ray Scattering ◽  
Wide Range ◽  
Michael Type Addition ◽  
Physical And Chemical ◽  
Hydrogel System

We developed and characterized a new hydrogel system based on the physical and chemical interactions of pectin partially modified with thiol groups and chitosan modified with acrylate end groups. Gelation occurred at high pectin thiol ratios, indicating that a low acrylated chitosan concentration in the hydrogel had a profound effect on the cross-linking. Turbidity, Fourier transform infrared spectroscopy, and free thiol determination analyses were performed to determine the relationships of the different bonds inside the gel. At low pH values below the pKa of chitosan, more electrostatic interactions were formed between opposite charges, but at high pH values, the Michael-type addition reaction between acrylate and thiol took place, creating harder hydrogels. Swelling experiments and Young’s modulus measurements were performed to study the structure and properties of the resultant hydrogels. The nanostructure was examined using small-angle X-ray scattering. The texture profile analysis showed a unique property of hydrogel adhesiveness. By implementing changes in the preparation procedure, we controlled the hydrogel properties. This hybrid hydrogel system can be a good candidate for a wide range of biomedical applications, such as a mucosal biomimetic surface for mucoadhesive testing.

Further Studies upon Chemical Factors Affecting the Breeding of Anopheles in Trinidad

1934 ◽  
Vol 25 (4) ◽  
pp. 491-494 ◽  
Author(s):  
P. A. Buxton
Keyword(s):  
Analytical Study ◽  
Chemical Constituents ◽  
Physical Factors ◽  
Factors Affecting ◽  
Early Stages ◽  
Freshwater Biology ◽  
Chemical Technique ◽  
Chemical Factors ◽  
Physical And Chemical

During the last decade, entomologists have made progress in understanding the environment in which certain insects live; in particular, we begin to understand the effect of certain physical and chemical factors, which make up a part of the environment. With this gain in knowledge, it is sometimes possible to forecast outbreaks of insects and of diseases conveyed by them, and one can sometimes say that a particular alteration of the environment will result in loss or gain. But so far as mosquitos are concerned, one must admit that though much work has been devoted to the analytical study of the water in which the early stages are passed, the results are disappointing. A consideration of the published work suggests several reasons for this. Investigation into the ecology of the mosquito has had a vogue, and much of it has been done by workers who were isolated and whose knowledge of chemical technique and freshwater biology was limited. Apart from that, the inherent difficulties are great, for the worker must hunt for the limiting chemical and physical factors among a host of others which are doubtless unimportant, and there are few clues to indicate which of the chemical constituents of the water affects the mosquito. The data are therefore voluminous and it is difficult to reduce them to order and present them so that they can be readily understood.

A global review of the downstream effects of small impoundments on stream habitat conditions and macroinvertebrates

2015 ◽  
Vol 23 (3) ◽  
pp. 257-262 ◽  
Author(s):  
John Gichimu Mbaka ◽  
Mercy Wanjiru Mwaniki
Keyword(s):  
Ecological Effects ◽  
Stream Habitat ◽  
Habitat Conditions ◽  
Qualitative And Quantitative ◽  
Downstream Effects ◽  
Physico Chemical ◽  
Low Head ◽  
Quantitative Analyses ◽  
Physical And Chemical ◽  
Run Of River

The downstream ecological effects of large impoundments have previously been reviewed; however, little is known about the downstream ecological effects of small man-made impoundments. In this review, we examine 94 papers focusing on the effects of small impoundments on stream habitat conditions and macroinvertebrates. Most studies (89.3%) address the effects of small impoundments on physical and chemical habitat conditions, while fewer studies (48.9%) address the effects on macroinvertebrates. In general, most studies report no significant downstream effects of small impoundments on physico-chemical variables, whereas macroinvertebrates richness and abundance increased or decreased. Mean effect sizes (as Cohen’s d) for physico-chemical variables range from −0.82 to 0.68 (small weir: −0.21 to 0.35; run-of-river dam: −0.82 to 0.64; low head dam: −0.49 to 0.68), and from −0.03 to 0.63 for macroinvertebrates abundance and richness. Our assessment of the published literature demonstrates the advantage of combining qualitative and quantitative analyses, and that, while small impoundments may have minimal significant effects on most physico-chemical variables, macroinvertebrates’ richness and density may be affected. This review is relevant for management and scientific communities to identify potential alterations of stream habitats and biota by small impoundments.

scholarly journals Sustainability Reporting as Mediation of Factors Affecting Financial Performance: Case in the Mining Sector in Indonesia

2020 ◽  
pp. 30-37
Author(s):  
Septiana Jumita ◽  
◽  
Taufiq Taufiq ◽  
Yusnaini Yusnaini ◽  
◽  
...  
Keyword(s):  
Financial Performance ◽  
Environmental Sustainability ◽  
Stock Exchange ◽  
Social Performance ◽  
Sustainability Reporting ◽  
Mining Sector ◽  
Report Generation ◽  
Factors Affecting ◽  
Management Personnel ◽  
Study Results

The problem of global warming due to environmental pollution has made it necessary for companies to be widely accountable to society about their performance. Therefore, today companies must not only report on the financial performance, but also report on all non-financial aspects of their activities, such as social and environmental. Sustainability reporting enables companies to report on environmental and social performance. It is not just report generation from collected data; instead it is a method to internalize and improve an company’s commitment to sustainable development in a way that can be demonstrated to both internal and external stakeholders. The study examines the factors influencing the company's financial performance through sustainability reporting in mining sector companies in Indonesia. The object of the study is a sample of 6 mining companies listed on the Indonesia Stock Exchange in 2014-2018. In this study, the authors use the Path Analysis – a form of multiple regression statistical analysis that is used to evaluate causal models by examining the relationships between a dependent variable and two or more independent variables. The study results show that sustainability reporting has a positive and significant impact on the financial performance of mining companies.In particular, the results of the analysis show that the company size and its liquidity have a positive and significant effect on the sustainability reporting. Leverage has a negative and significant effect on sustainability reporting. At the same time, the factors disclosed in the sustainability reporting have a significant impact on the financial performance of the companies. The results of this study can be useful for management personnel in the process of preparing a sustainability report by companies that want to attract the attention of investors.

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