scholarly journals Germination and development of M1 seedlings of two Selliera radicans Cav. accessions subjected to gamma radiation

2021 ◽  
Vol 53 (2) ◽  
pp. 36-46
Author(s):  
Fabián Soto ◽  
Patricia Peñaloza ◽  
Eduardo Oyanedel ◽  
Flavia Schiappacasse ◽  
Oscar Durán ◽  
...  

Selliera radicans is a creeping plant native to Chile, New Zealand and Australia. It is increasingly used in the ornamental industry, and there is interest in breeding it to create commercial varieties. The aim of this study was to determine the effects of different doses of gamma radiation applied to the seeds on the germination and development of seedlings (M1) and the LD50 of two accessions of Selliera radicans for use in the induction of mutations. Seeds of the Vichuquén and La Serena accessions were exposed to 0, 100, 200, 300, 400, 500, 600 and 700 Gy from a 60Co source. Weekly germination percentages along with seedling numbers and lengths were recorded. Vichuquén seeds were more sensitive to this physical agent. The LD50 was 243.9 Gy for Vichuquén and 445.6 Gy for La Serena. Seedling lengths reached almost 4 mm for Vichuquén and 11.3 mm for La Serena at 12 weeks after sowing. Doses lower than 200 Gy are recommended since higher doses do not allow the development of seedlings to the extended cotyledon stage. Highlights: This is the first radiosensitivity study for the Goodeniaceae family and therefore for the Selliera genus. This study shows the specific effect of gamma radiation at the level of germination and seedling formation according to accession of origin. This study could be used for the genetic improvement of Selliera radicans via the induction of mutations.

2012 ◽  
Vol 36 (2) ◽  
pp. 210-216 ◽  
Author(s):  
Ívina Catarina de Oliveira Guimarães ◽  
Joelma Pereira ◽  
Vanda Maria de Oliveira Cornélio ◽  
Luís Roberto Batista ◽  
Eric Batista Ferreira

Owing to its chemical composition and production chain, rice is susceptible to contamination by fungi. Among other techniques, the application of gamma radiation has been suggested as a method to ensure food safety. However, such radiation can alter the chemical composition of the food. Thus, the objective of the present work is to evaluate the centesimal composition, caloric value, pH, total titratable acidity, and coloration of polished white rice subjected to different doses of Co60 gamma radiation (0 kGy, 6.5 kGy, and 7.5 kGy). The results demonstrated that while gamma radiation did not cause significant alterations in the centesimal composition, caloric value, and titratable acidity of the rice, increasing doses substantially decreased the pH and intensified the coloration. Under controlled radiation conditions, a 6.5-kGy dose can render rice safe for consumption without significantly compromising its physical and physicochemical properties.


2011 ◽  
Vol 26 (6) ◽  
pp. 508-513 ◽  
Author(s):  
Patrícia Gomes da Silva ◽  
Daniele Cristina Cataneo ◽  
Fernanda Leite ◽  
Erica Nishida Hasimoto ◽  
Guilherme Antonio Moreira de Barros

PURPOSE: To compare analgesia traditionally used for thoracic sympathectomy to intrapleural ropivacaine injection in two different doses. METHODS: Twenty-four patients were divided into three similar groups, and all of them received intravenous dipyrone. Group A received intravenous tramadol and intrapleural injection of saline solution. Group B received intrapleural injection of 0.33% ropivacaine, and Group C 0.5% ropivacaine. The following aspects were analyzed: inspiratory capacity, respiratory rate and pain. Pain was evaluated in the immediate postoperative period by means of the visual analog scale and over a one-week period. RESULTS: In Groups A and B, reduced inspiratory capacity was observed in the postoperative period. In the first postoperative 12 hours, only 12.5% of the patients in Groups B and C showed intense pain as compared to 25% in Group A. In the subsequent week, only one patient in Group A showed mild pain while the remainder reported intense pain. In Group B, half of the patients showed intense pain, and in Group C, only one presented intense pain. CONCLUSION: Intrapleural analgesia with ropivacaine resulted in less pain in the late postoperative period with better analgesic outcomes in higher doses, providing a better ventilatory pattern.


1995 ◽  
pp. 33-33

Polimery ◽  
2021 ◽  
Vol 66 (11-12) ◽  
pp. 584-588
Author(s):  
Abdul Khaliq Mokhtar ◽  
Norsyahidah Mohd Hidzir ◽  
Irman Abdul Rahman ◽  
Faizal Mohamed ◽  
Nur Ain Mohd Radzali

The research focused on the synthesis of poly(tetrafluoroethylene) (PTFE) grafted with gold nanoparticles (AuNP). The Turkevich method, one of the common techniques of AuNP synthesis, was used to obtain an AuNP solution with a nanoparticle size of 20 nm. The PTFE-AuNP samples were subsequently irradiated and the absorbed doses were 0.5, 2, 5, 10 and 20 kGy. It was noticed that samples irradiated with 0.5 and 2 kGy were less stable and less concentrated than samples irradiated with higher doses due to aggregation and formation of precipitation after 30 days.


2013 ◽  
Vol 35 (2) ◽  
pp. 277-283
Author(s):  
A. Wosińska

Studies were undertaken on the effect of different doses of gamma radiation on survival rate of plants (germinated from irradiated seeds) for 5 China aster varieties specified at florescence time. During their growth under field conditions (from planting time to blooming) lethal effect of the radiation occurred in plants of all varieties and its level depended on dose and variety. Effect of 3 kR and 6 kR doses differed depending on variety and was not always harmful, but following irradiation with doses exceeding 6 kR a considerable decrease in survival rate was observed. Radioresistance of studied varieties - measured both: by LD<sub>50</sub> and LD<sub>l00</sub> - differed; depending on variety, LD<sub>50 </sub>and LD<sub>l00</sub> values fluctuated: from 6 to 9 kR and 12 to 15 kR respectively.


Vaccination failure is one of the major constraints to disease control in poultry. To investigate Infectious bursa disease (IBD)-vaccination failures (frequently/globally reported), batches of the Nigerian live-vaccine were tested for viral units before vaccinating following chick-groups: 16 doses (65,536 units), 8 doses (32,768 units), 4 doses (6,384 units), 2 doses (8,192 units), 1 dose (4,096 units), 1:2 dose (2,048 units), 1:4 dose (1,024 units), 1:8 dose (512 units), 1:16 dose (256 units) and control. Each batch gave 4,096 viral units. Mean bursa weight/body weight ratios (immune stimulation) and mean antibody titres of the chick-groups were 47.40 ±5.45 and 51.20 ±7.83; 44.25 ±7.28 & 48.00 ±9.24; 45.25 ± 4.28 and 64.00 ± 0.00; 43.00 ±7.58 and 101.60 ± 35.05; 44.60 ± 5.51 and 128.00 ± 0.00; 42.60 ± 6.23 and 268.80 ± 16.00; 40.50 ± 1.76 and 80.00 ±16.00; 31.40 ± 3.80 and 80.00 ± 27.71; 37.18 ± 4.07 and 89.60 ± 15.68 and 26.20 ± 3.31 and 19.20 ± 5.99, respectively. Half (2,048 units) of the recommended 1-dose gave optimal antibody-titre. The higher doses gave lower antibody-titres like the lower doses but immune stimulation continued to increase as doses/units increased. Both over-stimulating the immune system (too high vaccine-doses/viral-units/viral-virulence) and under-stimulation cause vaccination failure.


Author(s):  
Sudipta Dakua ◽  
Rakesh Gawaly ◽  
Pratyush Jain ◽  
Alok Pal Jain

The present study was designed to authenticate the anti-anxiety activity (by using elevated plus maze model) of methanolic extract of the leaves of Gentiana diffusa. by authors Swiss Albino mice were treated with different doses of the leaf extracts (200 mg / kg p.o.) and Diazepam (2mg/ kg, p.o) was used as a positive control. Results of study show that methanolic extract in higher doses (200 mg/kg) possesses marked anti-anxiety activity and was comparable to the effect produced by diazepam. The plant can be developed as a commercial source of anxiolytic agent. Further studies are in process to isolate the active constituent responsible for this activity and mechanism of action. Keywords: Leaves, Methanol, Anxiety, Diazepam


2018 ◽  
Vol 29 (3) ◽  
pp. 241-246 ◽  
Author(s):  
Augusto P.I. Gargiulo ◽  
María P. Gargiulo De Aranda ◽  
Mercedes M.L. Gargiulo ◽  
Angel J.M. Gargiulo ◽  
Andres Acuña ◽  
...  

AbstractBackground:In previous studies, we have observed that specificN-methyl-d-aspartic acid (NMDA) antagonists and non-NMDA antagonists injected within the nucleus accumbens septi (NAS) induced an anxiolytic-like effect in the plus maze test in rats. In the present study, the effect of intracanalicular blockade of NMDA receptors using dizocilpine in the plus maze was studied in male rats bilaterally cannulated NAS.Methods:Rats were divided into five groups that received either 1 μL injections of saline or dizocilpine (MK-801, [5R,10S]-[+]-5-methyl-10,11-dihydro-5H-dibenzo [a,d] cyclohepten-5,10-imine) in different doses (0.5, 1, 2, or 4 μg) 15 min before testing.Results:Time spent in the open arm increased under dizocilpine treatment with the two higher doses (2 and 4 μg, p<0.05), extreme arrivals were increased by the three higher doses (1 μg, p<0.05; 2 and 4 μg, p<0.01), and open arm entries by the three higher doses (1, 2, and 4 μg, p<0.05). A dose-effect relationship was observed in all cases.Conclusions:We conclude that dizocilpine-glutamatergic blockade in the accumbens lead to an anxiolytic-like effect and a behavioral disinhibition related to an increase in some motoric parameters, showing specific behavioral patterns.


Author(s):  
Abdenabi Ali Elamin ◽  
Waell H Alawad

This paper describes the effects of 60Cogamma radiation hardness of characteristic and parameters of Bipolar Junction Transistors in order to analyze the performance changes of the individual devices used in nuclear field. Bipolar Junction Transistor (BJT) of the type (BC-301) (npn) silicon, Transistor was irradiated by gamma radiation using 60Cosource at different doses (1, 2, 3, 4, and 5) KGy. The characteristics and parameter of Bipolar Junction Transistor was studied before and after irradiated by using Transistor Characteristics Apparatus with regulated power supplies. Obtained result showed that, the saturation voltage VCE(sat) of Bipolar Junction Transistor decreased because of the gain degradation of the transistor and increased silicon resistivity, Another parameter of a bipolar junction transistor affected by ionizing radiation is a collector-base leakage current, a strong increase of the current is caused by the build-up charge near the junction.


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