scholarly journals PHYSICAL AND CHEMICAL DEFENSES OF Cenostigma pyramidale (FABACEAE): A PIONEER SPECIES IN SUCCESSIONAL CAATINGA AREAS

2021 ◽  
Vol 34 (2) ◽  
pp. 398-409
Author(s):  
IZABELLA MARIA CINTRA RIBEIRO ◽  
EMILIA CRISTINA PEREIRA DE ARRUDA ◽  
ANTONIO FERNANDO MORAIS DE OLIVEIRA ◽  
JARCILENE SILVA DE ALMEIDA
Keyword(s):  
Chemical Defenses ◽  
Total Phenolic ◽  
Pioneer Species ◽  
Secretory Structures ◽  
Successional Stage ◽  
Successional Stages ◽  
The Difference ◽  
Physical And Chemical ◽  
Wax Load ◽  
Phenolics Compounds

ABSTRACT Cenostigma pyramidale, a pioneer species presents in all different successional stage (early, intermediate and late) of fifteen natural regeneration areas of Caatinga after land used changed and abandonment was used to investigates the morphological and physiological attributes that are very important to xeromorphic conditions as against herbivories. Leaf samples were collected to evaluate the percentage of the herbivory and index of sclerophylly. Anatomy, histochemistry, total phenolic content, epicuticular wax load, and n-alkanes profile were also performed. The results showed an inverse relationship between the percentage of herbivory and the index of sclerophylly. The leaves showed typical morphological and anatomical characteristics of xeric environments plants such as uniseriate epidermis and trichomes. Furthermore, it was also noticed a decrease in the overall thickness and the tissues according to the advancement of the successional stages. The histochemical revealed the presence of lipidic substances coating the epidermal layers, phenolics compounds stored in secretory structures, and starch in the mesophyll. The concentration of phenolics compounds indicating the difference from health leaves of plants between different stages of regeneration, but no difference when they were herbivored. The amount of cuticle wax did not change significantly with the successional stage. The profile of n-alkanes was characterized by the predominance of nonacosane (C29) and hentriacontane (C31). The C29 content decreases with the advancement of the successional stage, while the C31 content increases. All those attributes have a role to protect the plants to acclimate to the various environmental conditions of Caatinga.

scholarly journals Dormancy-defense syndromes and tradeoffs between physical and chemical defenses in seeds of pioneer species

Ecology ◽  
2018 ◽  
Vol 99 (9) ◽  
pp. 1988-1998 ◽  
Author(s):  
Paul-Camilo Zalamea ◽  
James W. Dalling ◽  
Carolina Sarmiento ◽  
A. Elizabeth Arnold ◽  
Carolyn Delevich ◽  
...  
Keyword(s):  
Chemical Defenses ◽  
Pioneer Species ◽  
Physical And Chemical ◽  
Defense Syndromes

scholarly journals Influence of the Bottom Color Modification and Material Color Modification Process on the Performance of Modified Poplar

Coatings ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 660
Author(s):  
Qingqing Liu ◽  
Di Gao ◽  
Wei Xu
Keyword(s):  
Chemical Properties ◽  
Target Color ◽  
Modification Process ◽  
Red Color ◽  
The Difference ◽  
Pre Treatment ◽  
Physical And Chemical ◽  
Surface Differentiation ◽  
Color Modification ◽  
And Chemical Properties

According to the old surface coating process of European and American furniture, the surface of modified poplar is first differentiated pre-treatment, and then the bottom color modification and material color modification are respectively applied to the modified poplar after the surface differentiation treatment. The visual physical quantity and physical and chemical properties were measured and compared with mahogany, which is commonly used in old furniture in Europe and America to explore the effect of colorants and coloring steps, as well as different surface pretreatments on the coloring effect. Finally, it is concluded that continuous coloring operations can narrow the difference in brightness and red color value in the coloring layer of modified poplar and mahogany. Continuous coloring operations increase the difference between the yellow-green color values of modified poplar and mahogany. Therefore, the coloring difference between modified poplar and mahogany was affected by the colorant and coloring steps. Through color accumulation, the gap between the two in the target color coloring effect can be reduced, thereby reducing the difference between the coloring effect of modified poplar and mahogany.

scholarly journals SOIL SEED BANK IN SEASONAL SEMIDECIDUOUS FOREST AND ABANDONED PASTURE

2016 ◽  
Vol 40 (6) ◽  
pp. 991-1001 ◽  
Author(s):  
Sustanis Horn Kunz ◽  
Sebastião Venâncio Martins
Keyword(s):  
Seed Bank ◽  
Soil Seed Bank ◽  
Life Forms ◽  
Successional Stage ◽  
Semideciduous Forest ◽  
Regeneration Stage ◽  
Significant Difference ◽  
Successional Stages ◽  
Pasture Area ◽  
Seasonal Semideciduous Forest

ABSTRACT The objective of this study was to characterize the seed bank in the soil of different successional stages of Seasonal Semideciduous Forest and abandoned pasture in order to understand the natural regeneration potential of these areas. At each successional stage, 30 samples of soil were collected in the rainy and dry seasons to evaluate the qualitative heterogeneity of the forest, at the regeneration stage (FEA) forest, intermediate regeneration stage forest (ISF) and pasture (PAS). The species were classified according to the life form, successional group and dispersion syndrome. The number of individuals germinated was significantly higher (p < 0.001) in the ISF and in the rainy season (15,949 individuals). Richness was higher in the pasture area (79 species), with a significant difference only between the environments. Most species are herbaceous (49.5%), pioneers (76.5%) and zoocory was the main dispersion syndrome (49% of species). The results show that seed bank in the fragment of the regeneration advanced stage forest presents the highest resilience potential, since it is formed by different life forms and, mainly, by early and late secondary species.

Physical and Chemical Sputtering at Very Low Ion Energy: the Importance of the Sputtering Threshold

1988 ◽  
Vol 129 ◽  
Author(s):  
Christoph Steinbruchel
Keyword(s):  
Threshold Energy ◽  
Surface Binding ◽  
Ion Energy ◽  
Chemical Sputtering ◽  
Surface Binding Energy ◽  
Physical Sputtering ◽  
Chemical Etch ◽  
Ion Energies ◽  
The Difference ◽  
Physical And Chemical

ABSTRACTA variety of data for physical etching (i.e. sputtering) and for ion-enhanced chemical etching of Si and SiO2 is analyzed in the very-low-ion-energy regime. Bombardment by inert ions alone, by reactive ions, and by inert ions in the presence of reactiveneutrals is considered. In all cases the etch yield follows a square root dependence on the ion energy all the way down to the threshold energy for etching. At the same time, the threshold energy has a non-negligible effect on the etch yield even at intermediate ion energies. The difference between physical and ion-enhanced chemical etch yields can be accounted for by a reduction in the average surface binding energy of the etch products and a corresponding reduction in the threshold energy for etching. These results suggest that, in general, the selectivity for ion-enhanced etch processes relative to physical sputtering can be increased significantly at low ion energy.

scholarly journals Molecular gas in the northern nucleus of Mrk 273: Physical and chemical properties of the disc and its outflow

2018 ◽  
Vol 617 ◽  
pp. A20 ◽  
Author(s):  
R. Aladro ◽  
S. König ◽  
S. Aalto ◽  
E. González-Alfonso ◽  
N. Falstad ◽  
...  
Keyword(s):  
Chemical Properties ◽  
Far Infrared ◽  
Molecular Gas ◽  
Dense Gas ◽  
Dynamical Mass ◽  
North West ◽  
North East ◽  
Dust Temperature ◽  
The Difference ◽  
Physical And Chemical

Aiming to characterise the properties of the molecular gas in the ultra-luminous infrared galaxy Mrk 273 and its outflow, we used the NOEMA interferometer to image the dense-gas molecular tracers HCN, HCO+, HNC, HOC+ and HC3N at ∼86 GHz and ∼256 GHz with angular resolutions of 4ʺ̣9 × 4ʺ̣5 (∼3.7 × 3.4 kpc) and 0ʺ̣61 × 0ʺ̣55 (∼460 × 420 pc). We also modelled the flux of several H2O lines observed with Herschel using a radiative transfer code that includes excitation by collisions and far-infrared photons. The disc of the Mrk 273 north nucleus has two components with decoupled kinematics. The gas in the outer parts (R ∼ 1.5 kpc) rotates with a south-east to north-west direction, while in the inner disc (R ∼ 300 pc) follows a north-east to south-west rotation. The central 300 pc, which hosts a compact starburst region, is filled with dense and warm gas, and contains a dynamical mass of (4 −5) × 109 M⊙, a luminosity of L′HCN = (3–4) × 108 K km s−1 pc2, and a dust temperature of 55 K. At the very centre, a compact core with R ∼ 50 pc has a luminosity of LIR = 4 × 1011 L⊙ (30% of the total infrared luminosity), and a dust temperature of 95 K. The core is expanding at low velocities ∼50–100 km s−1, probably affected by the outflowing gas. We detect the blue-shifted component of the outflow, while the red-shifted counterpart remains undetected in our data. Its cold and dense phase reaches fast velocities up to ∼1000 km s−1, while the warm outflowing gas has more moderate maximum velocities of ∼600 km s−1. The outflow is compact, being detected as far as 460 pc from the centre in the northern direction, and has a mass of dense gas ≤8 × 108 M⊙. The difference between the position angles of the inner disc (∼70°) and the outflow (∼10°) indicates that the outflow is likely powered by the AGN, and not by the starburst. Regarding the chemistry in Mrk 273, we measure an extremely low HCO+/HOC+ ratio of 10 ± 5 in the inner disc of Mrk 273.

TRUE AND APPARENT METABOLIZABLE ENERGY VALUES FOR POULTRY OF CANADIAN WHEATS AND OATS MEASURED BY BIOASSAY AND PREDICTED FROM PHYSICAL AND CHEMICAL DATA

1977 ◽  
Vol 57 (2) ◽  
pp. 365-374 ◽  
Author(s):  
I. R. SIBBALD ◽  
K. PRICE
Keyword(s):  
Metabolizable Energy ◽  
Chemical Data ◽  
Accuracy And Precision ◽  
Apparent Metabolizable Energy ◽  
The Difference ◽  
Variation Explained ◽  
Predicted Values ◽  
Naked Oats ◽  
Physical And Chemical ◽  
Better Than

Thirty samples of wheat and 28 samples of oats were assayed for true and apparent metabolizable energy (TME, AME). Within grains, the difference TME−AME increased with decreasing AME values; there is evidence that this trend is associated with reduced voluntary consumption of AME assay diets containing low energy grains. The TME and AME data were compared with ME values predicted from physical and chemical data describing the grains. Previously published prediction equations were tested and new equations were derived. Comparisons between predicted and observed data suggested that both the TME and AME values of wheat were predicted with insufficient accuracy and precision for practical use. Similar comparisons using the oat data showed high correlations between observed and predicted values, although the predictions were no more accurate than for wheat; however, when data describing four samples of naked oats were removed, the correlations were reduced substantially. Comparisons involving data for the hulled oats indicated that most equations were able to predict AME better than TME. Multiple regression analysis was used to identify those combinations of variables best able to predict TME data. No combination of variables was best for both wheat and oats. The combinations of variables used in published equations performed quite well. With four variables, the percentage of the TME variation explained was as high as 52 for wheat, 82 for oats and 64 for hulled oats. Predictions based on air-dry data are associated with higher correlations than those based on dry matter data, but the air-dry predictions are the less useful in practice. The reason for this is discussed.

scholarly journals Formulasi Krim Tabir Surya Ekstrak Etanol Daun Kersen (Muntingia calabura L.) untuk Kesehatan Kulit

2018 ◽  
Vol 28 (4) ◽  
pp. 263-270
Author(s):  
Anita Dwi Puspitasari ◽  
Dewi Andini Kunti Mulangsri ◽  
Herlina Herlina
Keyword(s):  
Ethanolic Extract ◽  
Sun Exposure ◽  
Ethanol Extract ◽  
Total Phenolic ◽  
Total Flavonoids ◽  
Physical Chemical ◽  
Rotary Evaporator ◽  
Maximum Protection ◽  
Physical And Chemical ◽  
Muntingia Calabura

Sunlight has many health benefits, but high sun exposure can also cause skin problems ranging from redness, inflammation, and the worst is triggering the appearance of skin cancer. One way to protect the skin from the sun is by using a sunscreen. Kersen Leaf (Muntingia calabura L.) has a high total flavonoids and total phenolic so that it can be used as a natural active ingredient for making sunscreen creams. The purpose of this study was to formulate and evaluate sunscreen cream preparations with variations in the concentration of ethanol extract of Kersen Leaf  Muntingia calabura L.) and to know the SPF value. Extract of kersen leaves (Muntingia calabura L.) using the maceration method with 70% ethanol. The extract was concentrated using a rotary evaporator. Four formulas were made with variations in the concentration of ethanol extract of kersen leaves. Formula 1 (cream base) without ethanolic extract of kersen leaves; formula 2 with ethanol extract of 1 gram kersen leaves; formula 3 with ethanol extract of 2 grams kersen leaves and formula 4 with ethanol extract of 3 grams kersen leaves. The four formulas were tested for physical, chemical and SPF values. Testing the SPF value using spectrophotometric method. For sticky power does not meet standard because it is less than 4 seconds. The Formula 1 SPF value is 0.1149; formula 2 is 7.6574 (extra protection); formula 3 is 13.7847 (maximum protection); and formula 4 is 19.0871 (ultra protection). The greater the concentration of ethanol extract of kersen leaves the greater the SPF value. From the results of the study, it was found that the four formulas fulfilled the requirements of physical and chemical characteristics, namely organoleptic, homogeneity, distribution, and viscosity, and had a significant SPF values, namely formula 2, 3 and 4. Abstrak Sinar matahari memiliki banyak manfaat bagi kesehatan, namun paparan sinar matahari yang tinggi juga dapat menyebabkan masalah kulit mulai dari kemerahan, peradangan, dan yang paling buruk adalah memicu munculnya kanker kulit. Salah satu cara untuk melindungi kulit dari sinar matahari yaitu dengan menggunakan tabir surya. Daun kersen (Muntingia calabura L.) mempunyai kandungan flavonoid total dan fenolik total yang tinggi sehingga dapat dimanfaatkan sebagai bahan aktif alami untuk pembuatan krim tabir surya. Tujuan penelitian ini untuk melakukan formulasi dan evaluasi sediaan krim tabir surya dengan variasi konsentrasi ekstrak etanol daun kersen (Muntingia calabura L.) serta mengetahui nilai SPF-nya. Ekstraksi daun kersen menggunakan metode maserasi dengan pelarut etanol 70%. Ekstrak dipekatkan menggunakan rotary evaporator. Dibuat empat formula dengan variasi konsentrasi ekstrak etanol daun kersen. Formula 1 (basis krim) tanpa ekstrak etanol daun kersen; formula 2 dengan ekstrak etanol daun kersen 1 gram; formula 3 dengan ekstrak etanol daun kersen 2 gram; dan formula 4 dengan ekstrak etanol daun kersen 3 gram. Keempat formula diuji karakteristik sifat fisika, kimia dan nilai SPFnya. Pengujian nilai SPF menggunakan metode spektrofotometri. Untuk daya lekat belum memenuhi standar karena kurang dari empat detik. Nilai SPF Formula 1 sebesar 0,1149; formula 2 sebesar 7,6574 (proteksi ekstra); formula 3 sebesar 13,7847 (proteksi maksimal); dan formula 4 sebesar 19,0871 (proteksi ultra). Semakin besar konsentrasi ekstrak etanol daun kersen semakin besar nilai SPF-nya. Dari hasil penelitian diperoleh bahwa keempat formula memenuhi persyaratan karakteristik sifat fisika dan kimia yaitu organoleptis, homogenitas, daya sebar pH, dan viskositas, serta memiliki nilai SPF yang bermakna yaitu formula 2, 3, dan 4.

scholarly journals Relationships between physical and chemical characteristics and calculated metabolizable energy values in barley and oats with highly variable volume weights

1978 ◽  
Vol 50 (3) ◽  
pp. 276-284
Author(s):  
Maija-Liisa Salo
Keyword(s):  
Crude Protein ◽  
Starch Content ◽  
Metabolizable Energy ◽  
Chemical Characteristics ◽  
Crude Fibre ◽  
Variable Volume ◽  
Physical And Chemical Characteristics ◽  
Volume Weight ◽  
The Difference ◽  
Physical And Chemical

61 samples of barley with a volume weight of 38—75 kg/hl, and 49 oat samples with a volume weight of 40—65kg/hl were analyzed for physical and chemical characteristics. The approximate metabolizable energy (ME) value was calculated from the composition. The physical characteristics varied more, but the starch content less, in barley than in oats. There was also a negative correlation between starch and crude protein, and ether extract level in barley, but not in oats. Therefore the difference between the ME values of the best and the poorest samples was only 12% for barley, but 27 % for oats. Both the starch and the crude protein content predicted the ME value well: R2 of starch was 78—94 %, and that of crude fibre 55—84 %. The volume weight still gave a good indication for barley, but not at all for oats.

scholarly journals Investigation on compatibility of PLA/PBAT blends modified by epoxy-terminated branched polymers through chemical micro-crosslinking

e-Polymers ◽  
2020 ◽  
Vol 20 (1) ◽  
pp. 39-54 ◽  
Author(s):  
Bo Wang ◽  
Yujuan Jin ◽  
Kai’er Kang ◽  
Nan Yang ◽  
Yunxuan Weng ◽  
...  
Keyword(s):  
Lactic Acid ◽  
Glass Transition ◽  
Sem Analysis ◽  
Branched Polymers ◽  
Poly Lactic Acid ◽  
Elongation At Break ◽  
Butylene Terephthalate ◽  
The Difference ◽  
Physical And Chemical ◽  
The Impact

AbstractIn this study, a type of epoxy-terminated branched polymer (ETBP) was used as an interface compati- bilizer to modify the poly lactic acid (PLA)/poly(butylene adipate-co-butylene terephthalate) (PBAT) (70/30) blends. Upon addition of ETBP, the difference in glass transition temperature between PLA and PBAT became smaller. By adding 3.0 phr of ETBP, the elongation at break of the PLA/PBAT blends was found increased from 45.8% to 272.0%; the impact strength increased from 26.2 kJ·m−2 to 45.3 kJ·m−2. In SEM analysis, it was observed that the size of the dispersed PBAT particle decreased with the increasing of ETBP content. These results indicated that the compatibility between PLA and PBAT can be effectively enhanced by using ETBP as the modifier. The modification mechanism was discussed in detail. It proposes that both physical and chemical micro-crosslinking were formed, the latter of which was confirmed by gel content analysis.

scholarly journals The importance of beech forests as reservoirs of moth diversity in Mediterranean Basin (Lepidoptera)

2018 ◽  
Vol 50 (2) ◽  
pp. 161-170 ◽  
Author(s):  
Marco Infusino ◽  
Stefano Scalercio
Keyword(s):  
Community Structure ◽  
Mediterranean Basin ◽  
Beech Forests ◽  
Number Of Species ◽  
Maturation Stages ◽  
Genetic Level ◽  
European Distribution ◽  
Successional Stages ◽  
The Difference ◽  
Almost All

Study analyzes the macrolepidoptera assemblages in beech woodlands of the Orsomarso Mountains (Pollino National Park, Southern Italy) to assess the role of beech forests in preserving diversity in Mediterranean Basin. Research was run between 2015 and 2016 in 15 stands representative of the main successional stages of forest maturation, placed between 990 and 1,475 meters of elevation. Monthlybased sampling was performed using UV-LED light traps. A total of 33,957 individuals belonging to 410 species was collected. The community is rich and the most abundant and characteristic species (Eilema lurideola, Operophtera fagata, Campaea margaritata) are almost all trophically linked to broadleaves or lichens. The community structure appears fairly constant and recognizable in all stands over the two years of sampling. Young beech forests hosted the greatest number of species compared to other forest maturation stages, though the difference is small. The greatest differences in the community structure are found in the clearings, where generalist and/or related to the herbaceous layer species are mostly represented. Biogeographically widely distributed species prevail, 87% of them having European or Asian-European distribution. There are a number of species of faunistic interest, among which Perizoma juracolaria, Chelis maculosa, Tiliacea citrago, Poecilocampa populi, Triphosa dubitata, Sideridis reticulata, Nebula senectaria, including 13 Italian endemics such as Coenotephria antonii. Populations of many species show significant genetic diversities compared to other European populations. The Orsomarso Mountains beech forests represent an important biodiversity reservoir, even at the genetic level, and show a good degree of naturalness.

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