Relations of shoot C, root C and root length with root-released C of two barley cultivars and the decomposition of root-released C in soil

1994 ◽  
Vol 74 (1) ◽  
pp. 17-22 ◽  
Author(s):  
J. G. Xu ◽  
N. G. Juma
Keyword(s):  
Direct Effect ◽  
Root Length ◽  
Experimental Period ◽  
Direct And Indirect Effects ◽  
Kinetics Analysis ◽  
Hordeum Vulgare L ◽  
Barley Cultivars ◽  
C Decomposition ◽  
Kinetics Of ◽  
Typic Cryoboroll

The production and utilization of root-derived C is fundamental to the functioning of ecosystems. The objectives of this experiment were to quantify the amount of root-released C produced by two barley (Hordeum vulgare L.) cultivars, to evaluate the direct and indirect effects of shoot C, root C and root length on the root-released C and to quantify the kinetics of the decomposition of root-released C in soil for two barley cultivars. Seedlings of two barley cultivars, Abee and Samson, were cultured in nutrient solution for 20 d and then pulse-labelled with 14C for 5 d. Samson released more C than Abee during the entire experimental period. Root length had the greatest direct effect on root-released C for the two barley cultivars. Kinetics analysis of the decomposition of root-released C added to soil showed that the labile components of the added material was 87.3% for Abee and 74.4% for Samson with half-lives of 4.3 d and 4.5 d, respectively. The half-lives of the resistant components of the root-released C added to soil and microbially-derived material were 37.7 d for Abee and 29.6 d for Samson, respectively. The amount of root-released C and its decomposition rate in soil varied with cultivars used. Key words: Root-released C, path analysis, direct effect, indirect effect, 14C, decomposition, Typic Cryoboroll

Ticlopidine and Clopidogrel (SR 25990C) Selectively Neutralize ADP Inhibition of PGE1-Activated Platelet Adenylate Cyclase in Rats and Rabbits

1991 ◽  
Vol 65 (02) ◽  
pp. 186-190 ◽  
Author(s):  
G Defreyn ◽  
C Gachet ◽  
P Savi ◽  
F Driot ◽  
J P Cazenave ◽  
...  
Keyword(s):  
Platelet Aggregation ◽  
Adenylate Cyclase ◽  
Direct Effect ◽  
Cyclic Nucleotide ◽  
Camp Accumulation ◽  
Rabbit Platelets ◽  
Camp Levels ◽  
Kinetics Of ◽  
Camp Elevation ◽  
Rat Platelets

SummaryTiclopidine and its potent analogue, clopidogrel, are powerful inhibitors of ADP-induced platelet aggregation. In order to improve the understanding of this ADP-selectivity, we studied the effect of these compounds on PGE1-stimulated adenylate cyclase and on the inhibition of this enzyme by ADP, epinephrine and thrombin. Neither drug changed the basal cAMP levels nor the kinetics of cAMP accumulation upon PGEj-stimulation in rat or rabbit platelets, which excludes any direct effect on adenylate cyclase or on cyclic nucleotide phosphodiesterase. However, the drop in cAMP levels observed after addition of ADP to PGEr stimulated control platelets was inhibited in platelets from treated animals. In contrast, the drop in cAMP levels produced by epinephrine was not prevented by either drug in rabbit platelets. In rat platelets, thrombin inhibited the PGEX-induced cAMP elevation but this effect seems to be entirely mediated by the released ADP. Under these conditions, it was not surprising to find that clopidogrel also potently inhibited that effect of thrombin on platelet adenylate cyclase. In conclusion, ticlopidine and clopidogrel selectively neutralize the ADP inhibition of PGEr activated platelet adenylate cyclase in rats and rabbits.

scholarly journals Study of deposition parameters and growth kinetics of ZnO deposited by aerosol assisted chemical vapor deposition

RSC Advances ◽  
2021 ◽  
Vol 11 (30) ◽  
pp. 18493-18499
Author(s):  
Sergio Sánchez-Martín ◽  
S. M. Olaizola ◽  
E. Castaño ◽  
E. Urionabarrenetxea ◽  
G. G. Mandayo ◽  
...  
Keyword(s):  
Chemical Vapor Deposition ◽  
Growth Kinetics ◽  
Vapor Deposition ◽  
Chemical Vapor ◽  
Kinetics Analysis ◽  
Deposition Parameters ◽  
Kinetics Of

Impact of deposition parameters, microstructure and growth kinetics analysis of ZnO grown by Aerosol-assisted Chemical Vapor Deposition (AACVD).

Plant Volatiles and Oviposition Behavior in the Selection of Barley Cultivars by Wheat Stem Sawfly (Hymenoptera: Cephidae)

2021 ◽  
Author(s):  
Buddhi B Achhami ◽  
Gadi V P Reddy ◽  
M L Hofland ◽  
Jamie D Sherman ◽  
Robert K D Peterson ◽  
...  
Keyword(s):  
Host Selection ◽  
Oviposition Behavior ◽  
Triticum Aestivum L ◽  
Wheat Cultivars ◽  
Hordeum Vulgare L ◽  
Wheat Stem Sawfly ◽  
Barley Cultivars ◽  
Hexenyl Acetate ◽  
Host Selection Behavior ◽  
Selection Decisions

Abstract Wheat stem sawfly, [Cephus cinctus (Hymenoptera: Cephidae)], females display complex behaviors for host selection and oviposition. Susceptible hollow stem wheat (Triticum aestivum L.) cultivars release a greater amount of attractive compound, (Z)-3-hexenyl acetate and receive a greater number of eggs compared to resistant solid stem wheat cultivars. However, barley (Hordeum vulgare L.) is becoming a more common host for C. cinctus in Montana. Therefore, how do host selection and oviposition behaviors on barley cultivars compare to what happens when encountering wheat cultivars? To answer this question, we carried out greenhouse experiments using two barley cultivars: ‘Hockett’ and ‘Craft’. Between these cultivars at Zadoks stages 34 and 49, we compared host selection decisions using a Y-tube olfactometer, compared oviposition behaviors on stems, and counted the number of eggs inside individual stems. In Y-tube bioassays, we found a greater number of C. cinctus females were attracted to the airstream passing over ‘Hockett’ than ‘Craft’ barley cultivars. Although the frequencies of oviposition behaviors were similar between these cultivars, the number of eggs was greater in ‘Hockett’. Volatile profiles indicated that the amount of linalool was greater in the airstream from ‘Craft’ than in ‘Hockett’ at Zadoks 34 while the amount of (Z)-3-hexenyl acetate was greater in airstream from ‘Hockett’ at both Zadoks 34 and 49. These results suggest that volatiles of barley plants influenced host selection behavior of ovipositing C. cinctus females, while other discriminating behaviors do not differ between cultivars.

Classification of cultivated barley (Hordeum vulgare). 1. Historical aspects, and phenetic character analysis of some characters by information theory and by spatial autocorrelation

1986 ◽  
Vol 64 (11) ◽  
pp. 2769-2773
Author(s):  
Bernard B. Baum
Keyword(s):  
Information Theory ◽  
Hordeum Vulgare ◽  
Spatial Autocorrelation ◽  
Theory Model ◽  
Kernel Weight ◽  
Hordeum Vulgare L ◽  
Department Of Agriculture ◽  
Character Analysis ◽  
Barley Cultivars

A brief historical sketch of the classification of barley (Hordeum vulgare L.) cultivars is presented along with reference to key reviews on this subject. Characters, utilized in the comprehensive study on the barley cultivars of North America by Aberg and Wiebe (U.S. Department of Agriculture Technical Bulletin 942), were subjected to a series of phenetic character analyses using an information theory model and a spatial autocorrelation model. The ranking of the 48 characters in order of their importance (for classification and identification purposes) from the character analysis by information theory was compared with the previous rating of characters made by Aberg and Wiebe and was found to differ significantly. Numerous trials of character analysis by spatial autocorrelation using various Minkowski distances, setting various values among three parameters, never yielded results comparable with those obtained by Aberg and Wiebe. Among those trials, a few combinations of values for the three parameters (X, Y, and Z) yielded results comparable with those obtained with character analysis by information theory. Those same combinations of values were found by Estabrook and Gates (Taxon, 33: 13–25) in their study of Banisteriopsis in 1984, where they also developed the method of character analysis by spatial autocorrelation. Kernel weight was found to be the most important character.

THE DIGESTIBILITY BY PIGS OF DRY MATTER, ENERGY, PROTEIN AND AMINO ACIDS IN WHEAT CULTIVARS. II. FIFTEEN CULTIVARS GROWN IN TWO YEARS, COMPARED WITH BONANZA AND FERGUS BARLEYS, AND 3CW-GRADE HARD RED SPRING WHEAT

1983 ◽  
Vol 63 (2) ◽  
pp. 393-406 ◽  
Author(s):  
D. M. ANDERSON ◽  
J. M. BELL
Keyword(s):  
Amino Acids ◽  
Crude Protein ◽  
Frost Damage ◽  
Cultivar Differences ◽  
Wheat Cultivars ◽  
Hordeum Vulgare L ◽  
Triticum Vulgare ◽  
Barley Cultivars ◽  
Protein Energy ◽  
Available Lysine

Fifteen wheat cultivars (Triticum vulgare L.) and two barley cultivars (Hordeum vulgare L.), some grown in two or three different years, were evaluated in two digestion trials with pigs of 40 kg initial weight. Some samples had frost damage. Each cultivar was measured for bulk weight (kg/hL), weight in g/1000 kernels, kernel plumpness and percent germination. The grains and feces were analyzed for gross energy, crude protein and amino acids. The diets comprised 95.7% ground grain, 0.5% chromic oxide, and mineral and vitamin supplements. Crude protein (N × 6.25) ranged from 11.1 to 19.7%. In terms of digestibility of energy, digestibility of protein, content of digestible crude protein (DCP), available lysine and digestible energy (DE), the wheat cultivars Inia-66 and Neepawa ranked highest, followed by Norquay, then Glenlea, Pitic-62 and PFW606A. Within cultivar, year-to-year differences were observed as well as some effects of frost damage. Cultivar differences in DE were found but DCP and available lysine were identified as the most important nutritional criteria for wheat to be used as the major grain in the animal diet. Environmental conditions affecting crop growth and seed maturity may be as important as genetic differences between cultivars in regard to nutritional quality evaluations as measured in these trials.Key words: Digestibility, wheat, protein, energy, amino acids, pigs

scholarly journals Using occupancy models to assess the direct and indirect impacts of agricultural expansion on species’ populations

2020 ◽  
Vol 29 (13) ◽  
pp. 3669-3688
Author(s):  
Asunción Semper-Pascual ◽  
Julieta Decarre ◽  
Matthias Baumann ◽  
Micaela Camino ◽  
Yamil Di Blanco ◽  
...  
Keyword(s):  
Land Use ◽  
Land Use Change ◽  
Direct Effect ◽  
Indirect Effects ◽  
Agricultural Land ◽  
Conservation Strategies ◽  
Agricultural Expansion ◽  
Direct And Indirect Effects ◽  
Occupancy Models ◽  
Occupancy Modelling

Abstract Land-use change is a global threat to biodiversity, but how land-use change affects species beyond the direct effect of habitat loss remains poorly understood. We developed an approach to isolate and map the direct and indirect effects of agricultural expansion on species of conservation concern, using the threatened giant anteater (Myrmecophaga tridactyla) in the Gran Chaco as an example. We reconstructed anteater occupancy change between 1985 and 2015 by fitting single-season occupancy models with contemporary camera-trap data and backcasting the models to 1985 and 2000 land-cover/use maps. Based on this, we compared the area of forest loss (direct effect of agricultural expansion) with the area where forests remained but occupancy still declined (indirect effect of agricultural expansion). Anteater occupancy decreased substantially since 1985, particularly after 2000 when agriculture expanded rapidly. Between 1985 and 2015, ~ 64,000 km2 of forest disappeared, yet occupancy declined across a larger area (~ 102,000 km2), extending far into seemingly untransformed habitat. This suggests that widespread sink habitat has emerged due to agricultural land-use change, and that species may lose their habitat through direct and indirect effects of agricultural expansion, highlighting the urgent need for broad-scale conservation planning in the Chaco. Appropriate management responses could proactively protect more habitat where populations are stable, and restore habitat or address causes of mortality in areas where declines occur. Our work also highlights how occupancy modelling combined with remote sensing can help to detect the direct and indirect effects of agricultural expansion, providing guidance for spatially targeting conservation strategies to halt extinctions.

Growth Kinetics of Interfacial Intermetallic Compound in Al(AA4343)/Steel(SUS316) Clad Strip

2020 ◽  
Vol 993 ◽  
pp. 447-456
Author(s):  
Xiao Jun Zhang ◽  
Kun Yuan Gao ◽  
Xiu Hua Hu ◽  
Yu Sheng Ding ◽  
Guo Zhan Wang ◽  
...  
Keyword(s):  
Growth Kinetics ◽  
Annealing Temperature ◽  
Optical Microscope ◽  
Alloy Layer ◽  
Kinetics Analysis ◽  
Growth Constant ◽  
Transmission Electron ◽  
Dispersive System ◽  
The Relationship ◽  
Kinetics Of

The composition and microstructure of intermetallic compounds (IMC) at the interface of aluminum(AA4343)-stainless steel(SUS316) were studied upon annealing at 550°C for 1h to 20h and at 610°C for 15min to 10h by means of optical microscope(OM) , scanning electron microscope (SEM) with energy dispersive system(EDS) and transmission Electron Microscopy (TEM). The results showed that the IMC was of 4.3μm to 36.1μm thick during heat treatment at 550°C for 1h to 20h, and the IMC contained Al-Fe-Si-Cr-Ni-Mo and Al-Fe-Si -Ni. During annealing at 610°C for 15min to 5h, the thickness of IMC was 31.2 μm to 208 μm, and the IMC were mainly of η-Fe2Al5 and τ10- Al4Fe1.7Si at 550°C for 10h. As the annealing time extended to 10h, natural delamination occurred at the interface between the aluminum alloy layer and IMC layer. The growth kinetics analysis showed that the relationship between the thickness of IMC “X” and time “t” followed the relational equation X=(kt)n. For AA4343(solid) - SUS316(solid), n was 1/2, and the growth constant k = 1.9×10-13m2/s at annealing temperature of 550 °C. When the temperature was 610°C, AA4343 - SUS316 was a liquid-solid contact reaction, n was 1, the growth constant k=1.45×10-8m/s.

scholarly journals Accelerated aging test and image analysis for barley seed

2019 ◽  
pp. 1546-1551
Author(s):  
Luciano Antônio Ebone ◽  
Inri Mateus Gonçalves ◽  
Nadia Canali Lângaro
Keyword(s):  
Digital Images ◽  
Seed Viability ◽  
Accelerated Aging ◽  
Seed Vigor ◽  
Barley Seed ◽  
High Yield ◽  
Germination Test ◽  
Hordeum Vulgare L ◽  
Barley Cultivars ◽  
Analysis System

Barley (Hordeum vulgare L.) planted area has increased in Brazil after a decline from 2005‒2009, but the country continues to import malt for the brewing industry. The physiological quality of the seed lot is essential for plant establishment and for screening for high yield grain. However, a uniform accelerated aging (AA) procedure has not been developed for testing barley seeds. Thus, this study aimed to determine the best AA method for measuring barley seed vigor. Seeds of three barley cultivars (BRS Cauê, BRS Brau, and MN 6021) were subjected to four AA treatment (T1: 41 °C for 72 h; T2: 42 °C for 48 h; T3: 42 °C for 60 h; and T4: 43 °C for 48 h). The following variables were evaluated using traditional vigor tests: seed viability in the first and last count of the germination test, number of seminal roots, shoot length, and radicle length. In addition, digital images of seedlings were acquired with the Seed Analysis System (SAS®) to compute seedling vigor, growth, and uniformity. AA methods T2 and T3 were effective in separating barley cultivars into vigor categories at day four of the germination test. Computer analysis of digital images of barley seedlings is a valuable tool for testing barley seed vigor. Accelerated aging methods T2 and T3 also gave the best separation in seed lot vigor and seedling growth using the SAS® index, respectively.

scholarly journals Kinetics of a Ca(2+)-sensitive cross-bridge state transition in skeletal muscle fibers. Effects due to variations in thin filament activation by extraction of troponin C.

1991 ◽  
Vol 98 (2) ◽  
pp. 233-248 ◽  
Author(s):  
J M Metzger ◽  
R L Moss
Keyword(s):  
Steady State ◽  
Direct Effect ◽  
Thin Filament ◽  
Near Neighbor ◽  
Troponin C ◽  
Isometric Tension ◽  
Cross Bridge ◽  
Filament Activation ◽  
Kinetics Of ◽  
Partial Extraction

The rate constant of tension redevelopment (ktr; 1986. Proc. Natl. Acad. Sci. USA. 83:3542-3546) was determined at various levels of thin filament activation in skinned single fibers from mammalian fast twitch muscles. Activation was altered by (a) varying the concentration of free Ca2+ in the activating solution, or (b) extracting various amounts of troponin C (TnC) from whole troponin complexes while keeping the concentration of Ca2+ constant. TnC was extracted by bathing the fiber in a solution containing 5 mM EDTA, 10 mM HEPES, and 0.5 mM trifluoperazine dihydrochloride. Partial extraction of TnC resulted in a decrease in the Ca2+ sensitivity of isometric tension, presumably due to disruption of near-neighbor molecular cooperativity between functional groups (i.e., seven actin monomers plus associated troponin and tropomyosin) within the thin filament. Altering the level of thin filament activation by partial extraction of TnC while keeping Ca2+ concentration constant tested whether the Ca2+ sensitivity of ktr results from a direct effect of Ca2+ on cross-bridge state transitions or, alternatively, an indirect effect of Ca2+ on these transitions due to varying extents of thin filament activation. Results showed that the ktr-pCa relation was unaffected by partial extraction of TnC, while steady-state isometric tension exhibited the expected reduction in Ca2+ sensitivity. This finding provides evidence for a direct effect of Ca2+ on an apparent rate constant that limits the formation of force-bearing cross-bridge states in muscle fibers. Further, the kinetics of this transition are unaffected by disruption of near-neighbor thin filament cooperativity subsequent to extraction of TnC. Finally, the results support the idea that the steepness of the steady-state isometric tension-calcium relationship is at least in part due to mechanisms involving molecular cooperativity among thin filament regulatory proteins.

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