relative variation
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2021 ◽  
Author(s):  
Benedict Coombes ◽  
John P. Fellers ◽  
Surbhi Grewal ◽  
Rachel Rusholme-Pilcher ◽  
Stella Hubbart-Edwards ◽  
...  

Wheat is a globally vital crop, but its limited genetic variation creates a challenge for breeders aiming to maintain or accelerate agricultural improvements over time. Introducing novel genes and alleles from wheat's wild relatives into the wheat breeding pool via introgression lines is an important component of overcoming this low variation but is limited by poor genomic resolution and limited understanding of the genomic impact of introgression breeding. By sequencing 17 hexaploid wheat/Ambylopyrum muticum introgression lines and the parent lines, we have precisely pinpointed the borders of introgressed segments. We report a genome assembly and annotation of Am. muticum that has facilitated the identification of Am. muticum resistance genes commonly introgressed in lines resistant to stripe rust. Our analysis has identified an abundance of structural disruption and homoeologous pairing across the introgression lines, likely caused by the suppressed Ph1 locus. mRNAseq analysis of six of these introgression lines revealed that introgressed genes tend to be downregulated, shifting the expression balance of triads towards suppression of the introgressed region, with no discernible compensation in the expression of the homoeologous copies. This analysis explores the genomic impact of introgression breeding and provides an affordable way for breeders to better characterise introgression lines and more effectively deploy wild relative variation.


Geofluids ◽  
2021 ◽  
Vol 2021 ◽  
pp. 1-13
Author(s):  
Kuan Wu ◽  
Shiliang Shi ◽  
Yi Lu ◽  
He Li ◽  
Min Li

Gas extraction is most commonly used to control gas disasters in coal mines. The distribution of the plastic zone around a borehole and the sealing quality are key factors affecting gas extraction. In this paper, the plastic zone was simulated by COMSOL, and a theoretical equation of the plastic zone radius was derived. In addition, an antispray hole equipment and the “two plugging and one injection” sealing technology were proposed. The results show that a larger borehole pore size corresponds to a larger plastic zone and larger range of pressure relief of the borehole. The error between the calculated and simulated plastic zone radii is within 1%, and the modified equation is applicable to Puxi mine. The loss and harm caused by borehole spraying are reduced by applying antispray hole equipment. By applying the “two plugging and one injection” sealing technology and phosphogypsum-based self-produced gas expansion paste material to block the borehole, the sealing quality is improved and an accurate gas mixing flow, pure flow, and concentration were obtained. As the plastic zone enlarges, the gas extraction flow gradually increases with, but the relative variation of flow first increases and subsequently decreases. Considering the safety and economy of construction, the optimal radius of the plastic zone is 64.9 mm.


2021 ◽  
Vol 10 (14) ◽  
pp. e470101422189
Author(s):  
Anuar José Mincache ◽  
Odair Gonçalves de Oliveira ◽  
Lilian Felipe da Silva Tupan ◽  
Daniel Matos Silva ◽  
Ivair Aparecido dos Santos ◽  
...  

In this work Bi1−xNdxFe0.99Co0.01O3 ceramics compositions were synthesized for x = 0.05, 0.20 and, y = 0.01. Structural refinement results show that most of the samples crystallized in a rhombohedral symmetry with R3c. Measurements magnetoelectric coefficient, show that the magnetoelectric coefficients are of second order. The electrical impedance characterization of in function external magnetic fields, has a relative variation of the real dielectric response, the loss tangent and the electrical impedance. The systems, as the DC magnetic field strength increased a gain in both the values of the dielectric constant variation, as well as the variation of the electrical impedance. In other words, the greater the intensity of the magnetic field, the greater your response. There were also significant variations with of the magnetic field AC.  


2021 ◽  
Vol 108 (Supplement_7) ◽  
Author(s):  
Oliver Luton ◽  
Osian James ◽  
Katie Mellor ◽  
Catherine Eley ◽  
Richard Egan ◽  
...  

Abstract Aim This study aimed to analyse the degree of relative variation in specialty-specific competencies required for Certification of Completion of Training (CCT) set by the UK Joint Committee for Surgical Training (JCST) 2021 curriculum. Methods Regulatory body guidance related to operative and non-operative surgical skill competencies required for CCT were analysed and compared. Results Wide inter-speciality variation was demonstrated in the minimum number of logbook cases (median 815; range 54-2100), indexed operations (8; 5-24), Procedure Based Assessments (35; 6-110). Academic competencies related to peer reviewed publications, communications to learned societies, and audits were aligned at zero, zero, and three across specialties respectively. Mandatory courses have been standardised with Advanced Trauma Life Support (ATLS) being the sole pre-requisite CCT for all. Discussion JCST certification guidelines have broadly standardised competency domains, yet large discrepancies persist regarding operative indicative numbers, and assessments. This article serves as a definitive CCT guide regarding prevailing changes.


PLoS ONE ◽  
2021 ◽  
Vol 16 (8) ◽  
pp. e0256786
Author(s):  
Vittorio Cherchi ◽  
Luigi Vetrugno ◽  
Giovanni Terrosu ◽  
Victor Zanini ◽  
Marco Ventin ◽  
...  

Background Despite current advances in liver transplant surgery, post-operative early allograft dysfunction still complicates the patient prognosis and graft survival. The transition from the donor has not been yet fully understood, and no study quantifies if and how the liver function changes through its transfer to the recipient. The indocyanine green dye plasma disappearance rate (ICG-PDR) is a simple validated tool of liver function assessment. The variation rate between the donor and recipient ICG-PDR still needs to be investigated. Materials and methods Single-center retrospective study. ICG-PDR determinations were performed before graft retrieval (T1) and 24 hours after transplant (T2). The ICG-PDR relative variation rate between T1 and T2 was calculated to assess the graft function and suffering/recovering. Matched data were compared with the MEAF model of graft dysfunction. Objective To investigate whether the variation rate between the donor ICG-PDR value and the recipient ICG-PDR measurement on first postoperative day (POD1) can be associated with the MEAF score. Results 36 ICG-PDR measurements between 18 donors and 18 graft recipients were performed. The mean donor ICG-PDR was 22.64 (SD 6.35), and the mean receiver’s ICG-PDR on 1st POD was 17.68 (SD 6.60), with a mean MEAF value of 4.51 (SD 1.23). Pearson’s test stressed a good, linear inverse correlation between the ICG-PDR relative variation and the MEAF values, correlation coefficient -0.580 (p = 0.012). Conclusion The direct correlation between the donor to recipient ICG-PDR variation rate and MEAF was found. Measurements at T1 and T2 showed an up- or downtrend of the graft performance that reflect the MEAF values.


2021 ◽  
Vol 2021 ◽  
pp. 1-13
Author(s):  
Dongxing Zhang ◽  
Wenkai Cao ◽  
Bing Qi

Regional agricultural drought vulnerability (RADV) is a complex nonlinear problem caused by the interaction of multiple factors, and an objective and systematic method is proposed by this paper to identify its influencing factors, which plays an important role in preventing and regulating the risks of regional agricultural drought. Firstly, to provide a reference for the evaluation problem in selecting the number of factors, the influencing factors affecting RADV are revealed by using the method of phase space reconstruction (PSR). Secondly, to rank the importance of influencing factors, a grey trend relational analysis (TGRA) method is proposed, considering the dynamic development relationship between the RADV index and the influencing factors and integrating the absolute and relative variation of sequences in each corresponding period. Finally, to reduce the collinearity between the influencing factors, a grey trend relational clustering (TGRC) analysis method is proposed. According to the above steps, the process of identifying factors based on PSR-TGRC method is formed. Taking Henan Province as an example, 14 main influencing factors and their effects on RADV are identified from all 42 factors, and the identification results which are consistent with the actual drought relief work show the rationality and practicality of PSR-TGRC method and provide theoretical support for formulating strategies of regional agricultural disaster prevention and mitigation.


2021 ◽  
Author(s):  
ZAKANIAINA RAJAOFARA ◽  
Philippe Leproux ◽  
Vincent COUDERC ◽  
Jean Rene Duclere ◽  
Marc Dussauze ◽  
...  

2021 ◽  
Vol 2021 ◽  
pp. 1-11
Author(s):  
Junhong Si ◽  
Yiqiao Wang ◽  
Genyin Cheng ◽  
Lin Li ◽  
Yitian Shao ◽  
...  

Considering the coal and gas outburst phenomenon in the mining space, this paper analyzes the main characteristics of coal and gas outburst accidents, defines the outburst airflow reversal degree, and constructs a simplified topology graph of tunneling ventilation system, while the air door is not destroyed. Using the numerical simulation method, this paper elaborates on the relationship between the outburst pressure and airflow reversal degree. The results indicate that the inlet pressure increases to 264 hPa and the outlet pressure increases to 289 hPa when the outburst pressure increases from 1 hPa to 1 MPa, and the relative variation coefficient of pressure decreases from 1501.5 to 1.62 in the inlet of return airway and decreases from 2002 to 1.65 in the outlet of return airway. Furthermore, the air velocity decreases from −1.38 to −284.44 m/s in the inlet and increases from 3.10 to 297.38 m/s in the outlet. Moreover, the gas concentration of the inlet and outlet in return airway increases rapidly with the increase of outburst pressure. When the outburst pressure is greater than 0.15 MPa, the gas concentration will be over 98% in tunneling ventilation system. This paper also finds out a cubic polynomial relationship existing between the reversal degree and the outburst pressure. It provides the prediction of coal and gas outburst and serves as a guidance in case mine ventilation disturbances occur.


2021 ◽  
Author(s):  
Serena Vigezzi ◽  
José Manuel Aburto ◽  
Iñaki Permanyer ◽  
Virginia Zarulli

Lifespan variation has been attracting increasingly greater attention as a measure of population health and mortality. Several studies have analysed periods of steady mortality decline, highlighting a strong inverse relationship between lifespan variation and life expectancy. Recent research has found that this association weakens, and even reverses, when mortality does not improve equally over age. However, to date no study has comprehensively explored the behaviour of lifespan variation when mortality increases significantly. Analysing three epidemics and two famines in Europe from the eighteenth to the twentieth centuries, we find that, during these events, relative lifespan variation increases, while absolute variation declines, and that subsequently both quickly revert to pre-crisis levels. Using decomposition techniques, we show that mortality at older ages leads to a temporary increase in absolute – but not relative – variation. Moreover, female lifespan variation is less affected by the crises than that of males, because of the higher impact of infant and child mortality on male lifespan variation. By underlining different trends of lifespan variation by sex and indicator, we offer new insight into the consequences of mortality crises. Contrary to what is often asserted, we also show that the choice of lifespan variation indicator is not always inconsequential.


2021 ◽  
Vol 7 ◽  
Author(s):  
Teemu Lemmettylä ◽  
Teemu Heikkinen ◽  
Olli Ohtonen ◽  
Stefan Lindinger ◽  
Vesa Linnamo

In the sport of cross-country skiing, equipment has a direct influence on results. Ski teams do extensive testing of different ski base grinds and products on a yearly basis. To achieve reliable results, the quality of methods used for testing skis needs to be taken in to account in addition to factors including the physical characteristics of testing personnel and changes in weather conditions. The aim of this study was to introduce a custom-made skitester, that was developed for testing skis on real snow, in laboratory conditions, and to evaluate its precision. The current skitester is capable of glide testing both classic and skate skis as well as kick simulation for the testing of grip waxes. In the present study, glide testing precision was completed in three different conditions. Velocity and pressure of skis were evaluated in three different temperature conditions. During kick simulation, precision was determined in one temperature condition. For glide testing, the precision of the measurement unit was able to distinguish the differences between skis with a relative variation of 0.6–1.1%. However, the track preparation process caused variation. For kick simulation, precision of the measurement unit was slightly higher (2.5%), and track preparation caused less variation. The skitester is capable of distinguishing the differences between both skate and classic cross-country skis with certain limitations.


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