Seedling vigour in wheat - sources of variation for genetic and agronomic improvement

2002 ◽  
Vol 53 (1) ◽  
pp. 41 ◽  
Author(s):  
R. A. Richards ◽  
Z. Lukacs

The early growth of wheat is slow compared with that of barley and triticale. This is expected to limit the yield of wheat in environments where greater seedling vigour is advantageous. To overcome the slow growth of wheat, genetic sources of seedling vigour are required for use in breeding programs, and/or ways to increase seedling growth by manipulating seed characteristics. This study reports (i) new sources of and 3 heights at cutting (cutting was done when the grass reached 0.5, 1, and 1.5 m above the ground). The N fertiliser treatment did not yield any significant difference in DMD, ND, or IVDMD. Height at cutting had a significant (P < 0.05) effect on rumen DMD and ND and their degradability characteristics for all incubation times. There was a reduction in DMD and ND and their degradability characteristics as plant height increased at cutting. Similarly, as height at cutting increased there was a decline in IVDMD. There was a positive linear correlation between IVDMD and both DMD and ND at 48, 72, 96, and 120 h (r = 0.917, 0.923, 0.921, and 0.850 for DMD; r = 0.795, 0.814, 0.787, and 0.787 for ND). Hence, further study on intake and performance of animals is suggested to develop Napier-based diets for smallholders.

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Te Miao ◽  
Peihua Wang ◽  
Nan Zhang ◽  
Yuguo Li

AbstractThe association between the footwear microclimate and microbial community on the foot plantar skin was investigated by experiments with three participants. Novel methods were developed for measuring in-shoe temperature and humidity at five footwear regions, as well as the overall ventilation rate inside the footwear. Three types of footwear were tested including casual shoes, running shoes, and perforated shoes for pairwise comparison of footwear microclimate and corresponding microbial community on the skin. The major findings are as follows: (1) footwear types make a significant difference to in-shoe temperature at the instep region with the casual shoes sustaining the warmest of all types; (2) significant differences were observed in local internal absolute humidity between footwear types, with the casual shoes sustaining the highest level of humidity at most regions; (3) the perforated shoes provided the highest ventilation rate, followed by running and casual shoes, and the faster the gait, the larger the discrepancy in ventilation rate between footwear types; (4) the casual shoes seemed to provide the most favorable internal environment for bacterial growth at the distal plantar skin; and (5) the bacterial growth at the distal plantar skin showed a positive linear correlation with the in-shoe temperature and absolute humidity, and a negative linear correlation with the ventilation rate. The ventilation rate seemed to be a more reliable indicator of the bacterial growth. Above all, we can conclude that footwear microclimate varies in footwear types, which makes contributions to the bacterial growth on the foot plantar skin.


Author(s):  
Richard Stone ◽  
Minglu Wang ◽  
Thomas Schnieders ◽  
Esraa Abdelall

Human-robotic interaction system are increasingly becoming integrated into industrial, commercial and emergency service agencies. It is critical that human operators understand and trust automation when these systems support and even make important decisions. The following study focused on human-in-loop telerobotic system performing a reconnaissance operation. Twenty-four subjects were divided into groups based on level of automation (Low-Level Automation (LLA), and High-Level Automation (HLA)). Results indicated a significant difference between low and high word level of control in hit rate when permanent error occurred. In the LLA group, the type of error had a significant effect on the hit rate. In general, the high level of automation was better than the low level of automation, especially if it was more reliable, suggesting that subjects in the HLA group could rely on the automatic implementation to perform the task more effectively and more accurately.


2019 ◽  
Vol 3 (1) ◽  
Author(s):  
Tim Lenz-Habijan ◽  
Pervinder Bhogal ◽  
Catrin Bannewitz ◽  
Ralf Hannes ◽  
Hermann Monstadt ◽  
...  

Abstract Background Flow diverters (FDs) are widely used in the treatment of intracranial aneurysms, but the required medication increases the risk of haemorrhagic complications and limits their use in the acute setting. Surface modified FDs may limit the need for dual antiplatelet therapy (DAPT). Hydrophilic polymer coating (HPC) may reduce the need of medication. Methods This explorative study, approved by the local authorities and the local welfare committee, compared stent behaviour and overall tissue response between HPC-coated FDs and uncoated FDs, both implanted into the common carotid arteries of eight New Zealand white rabbits. Endothelialisation, inflammatory response, and performance during implantation were assessed. Angiographic follow-up was performed to observe the patency of the devices after implantation and after 30 days. Histological examinations were performed at 30 days to assess foreign body reaction and endothelialisation. Kruskal-Wallis and Wilcoxon tests were used to compare non-parametric variables. Results Angiography showed that both coated and uncoated FDs performed well during implantation. All devices remained patent during immediate follow-up and after 30 days. Histopathology showed no significant difference in inflammation within the vessel wall between the two cohorts (2.12 ± 0.75 vs. 1.96 ± 0.79, p = 0.7072). Complete endothelialisation of the stent struts was seen with very similar (0.04 ± 0.02 mm vs. 0.04 ± 0.03 mm, p = 0.892) neoendothelial thickness between the two cohorts after 30 days. Conclusion Taking into account the limitation in sample size, non-significant differences between the HPC-coated and uncoated FDs regarding implantation, foreign body response, and endothelialisation were found.


Author(s):  
Zahra Safari ◽  
Reza Fouladi-Fard ◽  
Razieh Vahidmoghadam ◽  
Mohammad Raza Hosseini ◽  
Abolfazl Mohammadbeigi ◽  
...  

This study aimed to assess the awareness and performance of Qom citizens towards using disinfectants and compared its relationship with geographical distribution of COVID-19 outbreak in Qom, Iran. The study was conducted by a researcher-made questionnaire during April and May, 2020. COVID-19 incidence data for each district of city was obtained from health department of Qom province. Data were analyzed using Excel, SPSS and ArcView (GIS) softwares. It was found that the highest level of citizens’ awareness (52%) was in the weak range while their performance (56%) was in the good range. According to Spearman’s correlation analysis, there was a strong correlation (rho 0.95) between the total mean of awareness and performance (p < 0.01). The highest incidence rate of COVID-19 was in district 7 which had the lowest mean score in both awareness and performance. In addition, the results of ANOVA (LSD—least significant difference) showed that there was a significant difference (p < 0.05) between district 7—with lower mean scores in awareness and performance—and other districts. Overall, it is concluded that citizens’ awareness level was lower than that of their performance. This conclusion not only calls for more training programs to be implemented in public places, schools, universities and governmental offices, but it also necessitates maintaining a proper and timely training about using disinfectants.


1989 ◽  
Vol 53 (370) ◽  
pp. 257-262 ◽  
Author(s):  
D. D. Hogarth ◽  
J. E. T. Horne

AbstractA thin (100 m) cover of flat-lying, Recent, calcite-rich tuff at Ndale near Fort Portal, Uganda, unconformably overlies steeply dipping Precambrian metamorphic rocks. It is locally radioactive owing to uranium-rich pyrochlore minerals and lesser amounts of zircon, monazite, titanite, and an unidentified thorium phosphate. In one concentrate, four grains of uranpyrochlore and one grain of uranoan pyrochlore showed a positive linear correlation of Ti with U, and negative linear correlations of Ti with Na, F and Sr. Ta remained high and relatively constant [11 anal., ave. 14.5 (0.6)% Ta2O5]. In the same concentrate the composition of a separate grain of uranoan pyrochlore did not plot on these lines and Ta was comparatively low [2 anal., ave. 4.5 (0.3)% Ta2O5]. The data suggest two separate paths of differentiation. However, zoned grains were not observed. Unit cells were cubic with a = 10.351 ± 0.002 Å for a grain with 12.9% UO2tot and 10.333 ± 0.002 Å for a grain with 26.6% UO2tot. On heating in air the cell size decreased, possibly due to oxidation of U4+. The crystalline nature of these minerals can be attributed to a very young (4000–5000 yr) geological age.


2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
Charlotte Loumann Krogh ◽  
Charlotte Ringsted ◽  
Charles B. Kromann ◽  
Maria Birkvad Rasmussen ◽  
Tobias Todsen ◽  
...  

Introduction. The aim of this study was to explore the learning effect of engaging trainees by assessing peer performance during simulation-based training.Methods. Eighty-four final year medical students participated in the study. The intervention involved trainees assessing peer performance during training. Outcome measures were in-training performance and performance, both of which were measured two weeks after the course. Trainees’ performances were videotaped and assessed by two expert raters using a checklist that included a global rating. Trainees’ satisfaction with the training was also evaluated.Results. The intervention group obtained a significantly higher overall in-training performance score than the control group: mean checklist score 20.87 (SD 2.51) versus 19.14 (SD 2.65)P=0.003and mean global rating 3.25 SD (0.99) versus 2.95 (SD 1.09)P=0.014. Postcourse performance did not show any significant difference between the two groups. Trainees who assessed peer performance were more satisfied with the training than those who did not: mean 6.36 (SD 1.00) versus 5.74 (SD 1.33)P=0.025.Conclusion. Engaging trainees in the assessment of peer performance had an immediate effect on in-training performance, but not on the learning outcome measured two weeks later. Trainees had a positive attitude towards the training format.


2009 ◽  
Vol 87 (2) ◽  
pp. 139-151 ◽  
Author(s):  
Strahan Tucker ◽  
W. Don Bowen ◽  
Sara J. Iverson ◽  
Garry B. Stenson

Individuals of different age, sex, and morphology are expected to exhibit differences in dietary niches largely owing to sexual dimorphism, ontogenetic niche shifts, and resource polymorphism. Harp ( Pagophilus groenlandicus (Erxleben, 1777)) and hooded ( Cystophora cristata (Erxleben, 1777)) seals are geographically overlapping and highly migratory predators in the North Atlantic Ocean. These species differ in their diving behaviour, with hooded seals diving deeper, longer, and more associated with the continental shelf edge and deep ocean than harp seals. We examined blubber fatty acid (FA) composition (N = 37; 93% of total FA by mass) of harp (adults N = 294; juveniles N = 232) and hooded (adults N = 118; juveniles N = 38) seals to test hypotheses about sources of intrinsic (age and sex) and extrinsic (geographic location, season, year) variations in diets. A significant difference in FA profiles suggested dietary segregation between species. We found significant effects of sex and age class on FA profiles, with these being more pronounced in the highly size-dimorphic hooded seals than in harp seals. FA profiles of both species also varied between inshore and offshore sampling locations and between prebreeding and postbreeding periods. Finally, FA profiles of harp seals differed among years, which was coincident with large changes in prey distribution and availability in the mid-1990s.


2006 ◽  
Vol 57 (4) ◽  
pp. 477 ◽  
Author(s):  
R. De la Rosa ◽  
A. I. Kiran ◽  
D. Barranco ◽  
L. León

The juvenile period represents a serious impediment in olive breeding programs. Seedlings with long juvenile period are of very low interest for the breeder because their evaluation considerably delays the first stages of the breeding process. For this reason, the influence of seedling vigour (measured as plant height or stem diameter) on the characteristics at the adult stage was studied to establish useful negative preselection criteria on the basis of that relationship. Olive progenies from crosses and open pollinations of 12 different parents carried out in 1998 and 1999 were evaluated in the greenhouse and, afterwards, during the first 3 years of bearing in the open field. The results obtained indicate that early evaluation and selection for juvenile period can be performed at the seedling stage in olive progenies on the basis of vigour measurements. Selection for short juvenile period was valid irrespective of parentage and, therefore, could be efficient in a general context. No relationship between juvenile period and yield or fruit traits was found so that this preselection criterion would have no adverse effects on these characters.


2021 ◽  
Vol 28 (Supplement_1) ◽  
Author(s):  
B Morrison ◽  
N Chester ◽  
R Mcgregor-Cheers ◽  
G Kleinnibbelink ◽  
C Johnson ◽  
...  

Abstract Funding Acknowledgements Type of funding sources: Private grant(s) and/or Sponsorship. Main funding source(s): Canadian Institute of Health Research Michael Smith Foreign Study Supplement Background Image and performance enhancing drugs (IPED) cause cardiac enlargement and dysfunction. Previous work has not assessed impact of user status (current [CU] vs. past [PU]) or allometric scaling cardiac dimensions for individual differences in fat-free mass (FFM). Purpose To investigate CU and PU of IPED and allometric scaling on LV and RV remodeling in strength-trained athletes. Methods Thirty-four (29 ± 6 years; 82% male) strength-trained athletes were recruited. Fourteen were CU, 9 PU and 11 non-users (NU) of IPEDs.  Participants underwent bioelectric impedance body composition analysis, IPED and training questionnaire and 2D echocardiography with strain imaging. All structural data was allometrically scaled to FFM according to the laws of geometric similarity. Results CU and PU had significantly higher FFM compared to NU (82.4 ± 10.1 kg vs. 72.0 ± 6.3 kg vs. 58.2 ± 14.0 kg). Absolute values of all RV and LV size were larger between CU and NU. LV mean wall thickness (MWT) was larger in CU compared to PU but there were no differences between PU and NU. Allometric scaling eliminated all differences with exception of LV mass and LVMWT. LVEF was significantly lower in CU and PU compared to NU (55 ± 3 vs. 57 ± 4 vs. 61 ± 4) whilst LV GLS was lower in CU compared to PU and NU and LV GCS was lower in CU compared to NU but not PU. There was no significant difference between groups for RV functional indices. Conclusion  Strength-trained athletes currently using IPEDs have bi-ventricular enlargement as well as reduced LV function. Allometric scaling highlights that increased size is partially associated with a larger FFM, with exception of LVMWT which is independently increased through IPED use. PUs demonstrate reverse structural remodeling whilst functional differences partially remain. CU PU NU RVD1 (mm) 45 ± 5* 43 ± 6 37 ± 6 Scaled RVD1 (mm/kg^0.33) 10.5 ± 0.9 10.4 ± 1.5 9.7 ± 1.0 LVd (mm) 58 ± 7* 55 ± 4 50 ± 4 Scaled LVd (mm/kg^0.33) 13.4 ± 1.2 13.3 ± 0.7 13.1 ± 0.6 MWT (mm) 10 ± 1*” 8 ± 1 8 ± 1 Scaled MWT (mm/kg^0.33) 2.3 ± 0.2*” 2.0 ± 0.1 2.0 ± 0.2 LVEDV (ml) 169 ± 42* 135 ± 28 116 ± 28 Scaled LVEDV (ml/kg) 2.0 ± 0.4 1.9 ± 0.3 2.0 ± 0.2 LV Mass (g) 255 ± 85*” 179 ± 30 137 ± 40 LV mass index (g/kg) 3.1 ± 0.8* 2.5 ± 0.3 2.4 ± 0.4 * CU and NU “ CU and PU ^ PU and NU Abstract Figure. Myocardial strain imaging


Author(s):  
P. Masilamani ◽  
T. Eevera ◽  
T. Ramesh ◽  
S. Venkatesan

Background: The present investigation is an attempt to study the effect of different harvesting and threshing methods on germination and seedling vigour of dhaincha. The use of a combine harvester to harvest dhaincha will be an effective alternative method that has not been widely tried. However, work on different methods of harvesting and threshing of dhaincha is limited. Hence, a study was conducted to evaluate the impact of various harvesting and threshing methods on germination and seedling vigour of dhaincha. Methods: This study was conducted at Anbil Dharmalingam Agricultural College and Research Institute, TNAU, Tiruchirappalli, Tamil Nadu. The dhaincha crop was harvested and threshed using four different methods viz., manual harvesting and manual threshing, manual harvesting and threshing by tractor treading, manual harvesting and mechanical threshing and harvesting and threshing by combine harvester. The resultant seeds were tested for mechanical damage and germination potential. The experiment was laid in completely randomized block design. Germination was tested by roll towel method using 100 seeds in four replications. Germination percentage, root and shoot length were measured in seven days after sowing from ten randomly selected seedlings in each replication. For the estimation of dry matter production, ten seedlings were selected at random and kept in a hot air oven maintained at 85oC for 24 hours after measuring their root and shoot length and vigour index was calculated. Mechanical damage to seeds was observed by ferric chloride test. Seed recovery per cent was calculated based on the 100 kgs of dhaincha seeds were cleaned and graded treatment wise using cleaner cum grader and the seeds retained on the bottom sieve were weighed and expressed as per cent of total quantity of seed. Result: The results revealed that the significant difference was found among the different harvesting and threshing methods. The seeds harvested and threshed by manual method recorded 85 per cent germination followed by seeds harvested manually and threshed by mechanical threshing (84 per cent) and seeds harvested manually and threshed by tractor treading (80.5 per cent). The lowest germination of 80.0 per cent was recorded by combine harvesting. From this study, it could be inferred that combine harvester is a modern method for harvesting of dhaincha that saves time and labour when compared to all other methods.


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