Combined effects of contrast between poor and rich patches and overall nitrate concentration on Arabidopsis thaliana root system structure

2011 ◽  
Vol 38 (5) ◽  
pp. 364 ◽  
Author(s):  
Manuel Blouin ◽  
Ruben Puga-Freitas
Keyword(s):  
Root System ◽  
Nutrient Status ◽  
System Structure ◽  
System Response ◽  
Correlative Inhibition ◽  
The Rich ◽  
The Difference ◽  
Set Up ◽  
The Cost

The law of correlative inhibition states that roots in a richer environment develop more intensively if other roots of the same plant are in a poorer environment. This probably occurs only when the cost of emitting these roots in the rich patch is compensated by the advantage of having more roots, i.e. in situations where the difference in concentration between rich and poor patches is strong or the overall nutrient amount in the environment is low. For the first time, we tested root system response to combined gradients of contrast between poor and rich patches and of overall NO3– concentration in agar gels. We set up a factorial in vitro experiment crossing contrast (null, weak, strong heterogeneity) with overall NO3– concentration (deficient, optimal, excessive). We observed an increase in ramification density with increasing heterogeneity in deficient situations; but a decrease with increasing heterogeneity in excessive situations. The interaction between overall NO3– concentration and heterogeneity had a significant effect on root ramification density and the distribution of root length in diameter classes. The overall nutrient status of the soil has to be considered to understand the effect of heterogeneity on plant development at the morphological as well as at the molecular level.

Lupinus angustifolius has a plastic uptake response to heterogeneously supplied nitrate while Lupinus pilosus does not

2001 ◽  
Vol 52 (4) ◽  
pp. 505 ◽  
Author(s):  
V. Dunbabin ◽  
Z. Rengel ◽  
A. Diggle
Keyword(s):  
Root System ◽  
Uptake Rate ◽  
Root Length ◽  
Nitrate Uptake ◽  
Lupinus Angustifolius ◽  
Nitrate Losses ◽  
Nitrate Supply ◽  
Nitrate Uptake Rate ◽  
The Difference ◽  
Set Up

Uptake rates calculated from plants uniformly supplied with a nutrient will underestimate uptake under heterogeneous conditions. A split-root nutrient solution experiment was set up to compare the uptake rate of 2 lupin species (Lupinus angustifolius L., L. pilosus Murr.) under conditions of uniform and heterogeneous nitrate supply. Nitrate was supplied uniformly to the root system at 250 M (low), 750 M (high), or 1500 M (high), or in a split low/high or high/low combination between the upper and lower root system. While L. pilosus had a greater total nitrate uptake over the treatment period due to a higher total root length, L. angustifolius had 1.5–2.5 times greater nitrate uptake rate per unit of root length. L. angustifolius also had the capacity to increase the nitrate uptake rate in sections of the root system supplied locally with high nitrate, compared with a root system uniformly supplied with high nitrate. This increased uptake rate under heterogeneous supply enabled the plant to take up 74–94% of the total nitrate taken up when uniformly supplied with high nitrate, while only 58–72% would have been taken up without such a compensation mechanism. L. pilosus did not show this response. The difference between the response of these 2 species suggests that a range of nitrate uptake responses may exist across the lupin germplasm, and that it may be possible to select a lupin species with an enhanced ability to capture nitrate from the profile, thus decreasing nitrate losses from leaching.

scholarly journals Improvement of the grapes propagation technology in vitro

2020 ◽  
Vol 200 (9) ◽  
pp. 55-62
Author(s):  
Tat'yana Lekonceva ◽  
Aleksandr Fedorov
Keyword(s):  
Root System ◽  
Research Result ◽  
Statistical Processing ◽  
Test Tube ◽  
Sterile Culture ◽  
Clonal Micropropagation ◽  
Growing Medium ◽  
Set Up

Abstract. The aim of research is improvement of the production technology in vitro of the grapes Pamyati Dombkovskoy. Methods. Methods generally accepted in the practice of clonal micropropagation of plants were applied. There are sterilization of the starting material, introduction into culture, clonal micropropagation, and in vitro rooting, followed by adaptation to in vivo conditions. The study object was micro cuttings grapes of the cultural variety Pamyati Dombkovskoy. The experiments were set up in three replicates, one replication was at least 10 test tubes. Statistical processing of the data obtained was carried out by the dispersion method according to B. A. Dospekhov. The following parameters were taken into account: micro-shoots and microplants heights, leaves number, proliferation coefficient. Root development was assessed in points. The success of adaptation was considered as the percentage of adapted microplants to the total number planted in the substrate. At the stage of adaptation, we applied supplemented and developed by us technique during clonal micropropagation of the Angelica rose. Research result. Success of estanlishment explants was 40 % on Murashige and Skoog growing medium with a reduced content of macronutrients, when introduced into a sterile culture in vitro. The optimal concentration of 6-benzylaminopurine (6-BAP) was determined at the proliferation stage – 1 mg/l. There are decrease in the proliferation coefficient from 4.4 pcs/cutting to 3.3 and 2.9 pcs/cutting respectively with an increase in the concentration of cytokinin 6-BAP to 2.0 and 3.0 mg / l (LSD05 = 1.0). It was revealed that the best growing medium for rooting micrograpes is the environment according to Zlenko and others, when the best microplants development is achieved according to such morphometric parameters as microshoots height, leaves number and root system. On the medium Zlenko and others, microplants height was higher by 4.3 mm than the control with LSD05 = 2.7, the number of leaves was more by 0.5 with LSD05 = 0.3, and the root system of microplants is better developed by 0.4 points (LSD05 = 0.2). Scientific novelty. Positive results were received when rooted grapes cuttings were adapted after 14 days of cultivation on rooting medium, which allows to reduce the duration of micro grapes in a test tube in 2–4 times compared with the conventional method. The use of the biological product “Trichoderma Veride” for watering the soil substrate with the subsequent spraying of adaptable microplants with the organosilicone fertilizer “Siliplant” is recommended.

scholarly journals Optimization of Replaced Grinding Wheel Diameter for Surface Grinding Based on a Cost Analysis

Metals ◽  
2019 ◽  
Vol 9 (4) ◽  
pp. 448 ◽  
Author(s):  
Thi-Hong Tran ◽  
Anh-Tung Luu ◽  
Quoc-Tuan Nguyen ◽  
Hong-Ky Le ◽  
Anh-Tuan Nguyen ◽  
...  
Keyword(s):  
Mathematical Model ◽  
Cost Analysis ◽  
Surface Grinding ◽  
Grinding Wheel ◽  
Wheel Wear ◽  
Steel Material ◽  
The Difference ◽  
Set Up ◽  
The Cost ◽  
The Impact

Based on a cost analysis, a method of identifying and predicting optimum replaced grinding wheel diameter (De.op) in a surface grinding operation for 9CrSi steel material was developed in this study. The De.op value was determined by minimizing the cost function. An experimental design was set up, and a computational program was developed to perform the experiment in order to calculate the De.op value. Furthermore, the impact of the grinding process parameters such as the initial grinding wheel diameter, the grinding wheel width, the total dressing depth, the Rockwell hardness of the workpiece, the radial grinding wheel wear per dress, and the wheel life on the De.op value were investigated. Moreover, the impacts of the cost components such as the machine tool hourly rate and the grinding wheel cost on the De.op value were given. Based on that, a mathematical model was proposed to determine the De.op value. The predicted De.op value was also verified by an experiment. The obtained result shows that the difference between the experimental De.op value and the predicted De.op value is within 1.7%, indicating that the mathematical model proposed in the study is reliable.

Rural Entrepreneurship in Wintergreen Oil

2021 ◽  
pp. 231971452110072
Author(s):  
Dipesh Karki ◽  
Hari Gopal Risal
Keyword(s):  
Bargaining Power ◽  
Foreign Currency ◽  
Business Environment ◽  
Rural Entrepreneurship ◽  
The Usa ◽  
The Difference ◽  
Set Up ◽  
The Cost ◽  
Very High ◽  
Local Farmers

Wintergreen is a wild herb that grows in the hills of Nepal that can be used for extracting oil which has several medicinal values. It is being sold into premium-value markets in the USA by doTERRA Inc. doTERRA has a co-impact sourcing partnership with the NGO Choice Humanitarian, scouts the local farmers or entrepreneurs and helps them set up the production business. The difference between the price of the final product and the price that local entrepreneurs get is very high. Despite this, the venture has created a new opportunity for local farmers to make large profit as the cost of production is low. However, the business itself has several challenges from scalability and sustainability aspects. Further, the price is set by the single buyer and the market has monopsonist characteristics; hence, the producer has less bargaining power. Despite these challenges, creating a better business environment enables the export of essential oil and that can be a potential foreign currency source for country like Nepal.

A Heparin-coated Circuit Maintains Platelet Aggregability in Response to Shear Stress in an In Vitro Model of Cardiopulmonary Bypass

1998 ◽  
Vol 80 (09) ◽  
pp. 437-442 ◽  
Author(s):  
I. Hioki ◽  
K. Onoda ◽  
T. Shimono ◽  
H. Shimpo ◽  
K. Tanaka ◽  
...  
Keyword(s):  
Shear Stress ◽  
Cardiopulmonary Bypass ◽  
Membrane Skeleton ◽  
Platelet Glycoprotein ◽  
Platelet Surface ◽  
Platelet Aggregability ◽  
Vitro Model ◽  
Platelet Defects ◽  
Set Up

SummaryAlterations in platelet aggregability may play a role in the pathogenesis of qualitative platelet defects associated with cardiopulmonary bypass (CPB). We circulated fresh heparinized whole blood through tubing sets coated with heparin (C group, n = 10) and through non-coated sets (N group, n = 10) as a simulated CPB circuit. Shear stress (108 dyne/cm2)-induced platelet aggregation (hSIPA), plasma von Willebrand factor (vWF) activity and platelet glycoprotein (GP) Ib expression were measured, before, during, and after this in vitro set up of circulation. In the two groups, the extent of hSIPA significantly decreased during circulation and was partially restored after circulation. Decreases in the extent of hSIPA were significantly less with use of heparin-coated circuits. There was an equivalent reduction in plasma vWF activity, in the two groups. Expression of platelet surface GP Ib decreased significantly during circulation and recovered after circulation. Reduction of surface GP Ib expression during circulation was significantly less in the C group than that in the N group. Decrease in surface GP Ib expression correlated (r = 0.88 in either group) with the magnitude of hSIPA, in the two groups. The progressive removal of surface GP Ib was mainly attributed to redistribution of GP Ib from the membrane skeleton into the cytoskeleton. Our observations suggest that use of heparin-coated circuits partly blocks the reduction of hSIPA, as a result of a lesser degree of redistribution of GP Ib.

On the Role of Transferrin in 67Ga Uptake by Tumor Cells

1988 ◽  
Vol 27 (04) ◽  
pp. 151-153
Author(s):  
P. Thouvenot ◽  
F. Brunotte ◽  
J. Robert ◽  
L. J. Anghileri
Keyword(s):  
Specific Binding ◽  
Subcellular Fractionation ◽  
Animal Blood ◽  
Tumor Bearing ◽  
Cell Structures ◽  
The Difference ◽  
Sarcoma Cells ◽  
In Vitro Uptake

In vitro uptake of 67Ga-citrate and 59Fe-citrate by DS sarcoma cells in the presence of tumor-bearing animal blood plasma showed a dramatic inhibition of both 67Ga and 59Fe uptakes: about ii/io of 67Ga and 1/5o of the 59Fe are taken up by the cells. Subcellular fractionation appears to indicate no specific binding to cell structures, and the difference of binding seems to be related to the transferrin chelation and transmembrane transport differences

Enhancement of ADP-induced Platelet Aggregation by Adrenaline in Vivo and Its Prevention

1973 ◽  
Vol 29 (02) ◽  
pp. 490-498 ◽  
Author(s):  
Hiroh Yamazaki ◽  
Itsuro Kobayashi ◽  
Tadahiro Sano ◽  
Takio Shimamoto
Keyword(s):  
Platelet Count ◽  
Platelet Aggregation ◽  
Platelet Rich Plasma ◽  
The Other ◽  
Endothelial Surface ◽  
Important Interaction ◽  
Blood Coagulability ◽  
The Difference

SummaryThe authors previously reported a transient decrease in adhesive platelet count and an enhancement of blood coagulability after administration of a small amount of adrenaline (0.1-1 µg per Kg, i. v.) in man and rabbit. In such circumstances, the sensitivity of platelets to aggregation induced by ADP was studied by an optical density method. Five minutes after i. v. injection of 1 µg per Kg of adrenaline in 10 rabbits, intensity of platelet aggregation increased to 115.1 ± 4.9% (mean ± S. E.) by 10∼5 molar, 121.8 ± 7.8% by 3 × 10-6 molar and 129.4 ± 12.8% of the value before the injection by 10”6 molar ADP. The difference was statistically significant (P<0.01-0.05). The above change was not observed in each group of rabbits injected with saline, 1 µg per Kg of 1-noradrenaline or 0.1 and 10 µg per Kg of adrenaline. Also, it was prevented by oral administration of 10 mg per Kg of phenoxybenzamine or propranolol or aspirin or pyridinolcarbamate 3 hours before the challenge. On the other hand, the enhancement of ADP-induced platelet aggregation was not observed in vitro, when 10-5 or 3 × 10-6 molar and 129.4 ± 12.8% of the value before 10∼6 molar ADP was added to citrated platelet rich plasma (CPRP) of rabbit after incubation at 37°C for 30 second with 0.01, 0.1, 1, 10 or 100 µg per ml of adrenaline or noradrenaline. These results suggest an important interaction between endothelial surface and platelets in connection with the enhancement of ADP-induced platelet aggregation by adrenaline in vivo.

Reliability of a Single β-Thromboglobulin Measurement in a Diabetic Population : Importance of PGE1 in Anticoagulant Mixture

1987 ◽  
Vol 57 (02) ◽  
pp. 201-204 ◽  
Author(s):  
P Y Scarabin ◽  
L Strain ◽  
C A Ludlam ◽  
J Jones ◽  
E M Kohner
Keyword(s):  
In Vitro Release ◽  
Mean Value ◽  
Reliable Estimate ◽  
Diabetic Patients ◽  
Single Measurement ◽  
Diabetic Population ◽  
The Difference ◽  
Vitro Release

SummaryDuring the collection of samples for plasma β-thromboglobulin (β-TG) determination, it is well established that artificially high values can be observed due to in-vitro release. To estimate the reliability of a single β-TG measurement, blood samples were collected simultaneously from both arms on two separate occasions in 56 diabetic patients selected for a clinical trial. From each arm, blood was taken into two tubes containing an anticoagulant mixture with (tube A) and without (tube B) PGE!. The overall mean value of B-TG in tube B was 1.14 times higher than in tube A (p <0.01). The markedly large between-arms variation accounted for the most part of within-subject variation in both tubes and was significantly greater in tube B than in tube A. Based on the difference between B-TG values from both arms, the number of subjects with artifically high B-TG values was significantly higher in tube B than in tube A on each occasion (overall rate: 28% and 14% respectively). Estimate of between-occasions variation showed that B-TG levels were relatively stable for each subject between two occasions in each tube. It is concluded that the use of PGEi decreases falsely high B-TG levels, but a single measurement of B-TG does not provide a reliable estimate of the true B-TG value in vivo.

Rapid, Refined, and Robust Method for Expression, Purification, and Characterization of Recombinant Human Amyloid-beta M1-42

2019 ◽  
Author(s):  
Priya Prakash ◽  
Travis Lantz ◽  
Krupal P. Jethava ◽  
Gaurav Chopra
Keyword(s):  
Amyloid Beta ◽  
Western Blots ◽  
Force Microscopy ◽  
E Coli ◽  
Atomic Force ◽  
Set Up ◽  
Short Time

Amyloid plaques found in the brains of Alzheimer’s disease (AD) patients primarily consists of amyloid beta 1-42 (Ab42). Commercially, Ab42 is synthetized using peptide synthesizers. We describe a robust methodology for expression of recombinant human Ab(M1-42) in Rosetta(DE3)pLysS and BL21(DE3)pLysS competent E. coli with refined and rapid analytical purification techniques. The peptide is isolated and purified from the transformed cells using an optimized set-up for reverse-phase HPLC protocol, using commonly available C18 columns, yielding high amounts of peptide (~15-20 mg per 1 L culture) in a short time. The recombinant Ab(M1-42) forms characteristic aggregates similar to synthetic Ab42 aggregates as verified by western blots and atomic force microscopy to warrant future biological use. Our rapid, refined, and robust technique to purify human Ab(M1-42) can be used to synthesize chemical probes for several downstream in vitro and in vivo assays to facilitate AD research.

M. V. Nadkarni. Farmer's Movements in India. New Delhi: Allied Publishers Pvt. Ltd., 1987.237 pp.,Price: (hardbound edition) Rupees (Indian) 100.00.

1988 ◽  
Vol 27 (3) ◽  
pp. 333-335
Author(s):  
Khwaja Sarmad
Keyword(s):  
Tamil Nadu ◽  
Rural Poverty ◽  
Price Policy ◽  
New Delhi ◽  
Root Cause ◽  
The Subject ◽  
The Rich ◽  
Land Holdings ◽  
Set Up ◽  
Agricultural Price

This book is a comprehensive analysis of farmers' movements in India with a focus on the movements in Tamil Nadu, Maharashtra, Punjab and Karnatka. It examines the economic, social and political aspects of the farmers' struggle for a better deal within regional and national perspectives and evaluates the potential impact of these struggles on economic development in general, and on rural development, in particular. In a most competent way the author has presented the current state of the debate on the subject. He deals exhaustively with the subject of agricultural price policy and argues against the proposition that favourable price-setting for farm products is adequate to alleviate rural poverty. A better way to tackle this problem is to improve the per capita output in the rural sector, since the root cause of the problem is not unfavourable terms of trade but the increasing proportion of land holdings, which are economically not viable. Agricultural price policy is analyzed within the context of class relations, which enables to establish a link between the economic and political demands of the farmers. This analysis leads the author to conclude, that in contrast with the peasants' movements in India, which helped to break up the feudal agrarian set-up, the recent farmers' movements, with a few exceptions, have little revolutionary content. Their leadership has been appropriated by the rich landowners, who have transformed the movements into a lobby for advancing their own interests, within the existing power structure, to the neglect of the poorer peasantry.

Sign in / Sign up

Export Citation Format

Share Document