An evaluation of some criteria used in selecting large-yielding tea clones

1971 ◽  
Vol 76 (1) ◽  
pp. 143-156 ◽  
Author(s):  
M. J. Green
Keyword(s):  
Growth Rate ◽  
Cross Section ◽  
Vegetative Propagation ◽  
Selection Criterion ◽  
Calcium Oxalate Crystals ◽  
Rate Of Development ◽  
Phloem Parenchyma ◽  
Plant Grown ◽  
Rates Of Growth ◽  
Selection Of

SUMMARYSeveral criteria which have been used hitherto in the hope of selecting large-yielding clones of tea have been examined. The heights, girths, root weights and branching a gles of young seedlings in the nursery are correlated with the sizes and yields of the same plants when mature, but not with the rates of growth in the nursery, or the yields at maturity, of the plants derived from these seedlings by vegetative propagation. The pruning weight, size and yield of a mature plant grown from seed are not related to the rate of growth in the nursery or the yield at maturity of the clone derived from that plant. The proportion of cuttings which form roots and the growth rate of the cuttings of a clone are not related to the yield of the clone. It is concluded that these criteria are, at best, of limited value in the selection of large-yielding clones.Phloem Index, which is the number of calcium oxalate crystals counted in the phloem parenchyma in a cross-section of the petiole, varies with the age and rate of development of the shoot from which the petiole is taken and with the concentration of nutrients in the soil. It is therefore not useful as an alternative selection criterion under normal field conditions.

Large Area DPB Free (111) β-SiC Thick Layer Grown on (0001) α-SiC Nominal Surfaces by the CF-PVT Method

2005 ◽  
Vol 483-485 ◽  
pp. 225-228 ◽  
Author(s):  
Didier Chaussende ◽  
Laurence Latu-Romain ◽  
Laurent Auvray ◽  
M. Ucar ◽  
Michel Pons ◽  
...  
Keyword(s):  
Growth Rate ◽  
Optical Microscopy ◽  
Cross Section ◽  
Thick Layer ◽  
Vapour Transport ◽  
Large Area ◽  
Continuous Feed ◽  
Heating Up ◽  
Cross Section Geometry ◽  
Selection Of

Thick (111) oriented β-SiC layers have been grown by hetero-epitaxy on a (0001) a-SiC substrate with the Continuous Feed-Physical Vapour Transport (CF-PVT) method. The growth rate was 68 µm/h at a pressure of 2 torr and a temperature of 1950°C. The nucleation step of the β-SiC layer during the heating up of the process was studied in order to manage first the a to b heteropolytypic transition and second the selection of the b-SiC orientation. With a adapted seeding stage, we grew a 0.4mm thick layer almost free of Double Positioning Boundaries on a 30mm diameter sample. First observations of the layer by cross-polarised optical Microscopy are presented both in planar view and in cross section geometry.

Measurement of growth rates for single crystals and pressed tablets of CuSO4.5 H2O on a rotating disc

1989 ◽  
Vol 54 (11) ◽  
pp. 2951-2961 ◽  
Author(s):  
Miloslav Karel ◽  
Jaroslav Nývlt
Keyword(s):  
Growth Rate ◽  
Single Crystal ◽  
Single Crystals ◽  
Growth Rates ◽  
Diffusion Coefficients ◽  
Preferred Orientation ◽  
Rotating Disc ◽  
Dissolution Rates ◽  
Rates Of Growth ◽  
Good Agreement

Measured growth and dissolution rates of single crystals and tablets were used to calculate the overall linear rates of growth and dissolution of CuSO4.5 H2O crystals. The growth rate for the tablet is by 20% higher than that calculated for the single crystal. It has been concluded that this difference is due to a preferred orientation of crystal faces on the tablet surface. Calculated diffusion coefficients and thicknesses of the diffusion and hydrodynamic layers in the vicinity of the growing or dissolving crystal are in good agreement with published values.

Discovery of five new Galactic symbiotic stars in the VPHAS+ survey

2021 ◽  
Vol 502 (2) ◽  
pp. 2513-2517
Author(s):  
Stavros Akras ◽  
Denise R Gonçalves ◽  
Alvaro Alvarez-Candal ◽  
Claudio B Pereira
Keyword(s):  
Spectroscopic Data ◽  
Selection Criterion ◽  
Optical Spectra ◽  
Emission Lines ◽  
High Rate ◽  
Symbiotic Stars ◽  
Selection Of

ABSTRACT We report the validation of a recently proposed infrared (IR) selection criterion for symbiotic stars (SySts). Spectroscopic data were obtained for seven candidates, selected from the SySt candidates of Akras et al. by employing the new supplementary IR selection criterion for SySts in the VST/OmegaCAM Photometric H-Alpha Survey. Five of them turned out to be genuine SySts after the detection of H α, He ii, and [O iii] emission lines as well as TiO molecular bands. The characteristic O vi Raman-scattered line is also detected in one of these SySts. According to their IR colours and optical spectra, all five newly discovered SySts are classified as S-type. The high rate of true SySts detections of this work demonstrates that the combination of the H α emission and the new IR criterion improves the selection of target lists for follow-up observations by minimizing the number of contaminants and optimizing the observing time.

scholarly journals Improved selection of participants in genetic longevity studies: family scores revisited

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Mar Rodríguez-Girondo ◽  
Niels van den Berg ◽  
Michel H. Hof ◽  
Marian Beekman ◽  
Eline Slagboom
Keyword(s):  
Missing Data ◽  
The Netherlands ◽  
Family Size ◽  
Simulation Study ◽  
Missing Values ◽  
Selection Criterion ◽  
Limited Success ◽  
Main Challenge ◽  
Historical Sample ◽  
Selection Of

Abstract Background Although human longevity tends to cluster within families, genetic studies on longevity have had limited success in identifying longevity loci. One of the main causes of this limited success is the selection of participants. Studies generally include sporadically long-lived individuals, i.e. individuals with the longevity phenotype but without a genetic predisposition for longevity. The inclusion of these individuals causes phenotype heterogeneity which results in power reduction and bias. A way to avoid sporadically long-lived individuals and reduce sample heterogeneity is to include family history of longevity as selection criterion using a longevity family score. A main challenge when developing family scores are the large differences in family size, because of real differences in sibship sizes or because of missing data. Methods We discussed the statistical properties of two existing longevity family scores: the Family Longevity Selection Score (FLoSS) and the Longevity Relatives Count (LRC) score and we evaluated their performance dealing with differential family size. We proposed a new longevity family score, the mLRC score, an extension of the LRC based on random effects modeling, which is robust for family size and missing values. The performance of the new mLRC as selection tool was evaluated in an intensive simulation study and illustrated in a large real dataset, the Historical Sample of the Netherlands (HSN). Results Empirical scores such as the FLOSS and LRC cannot properly deal with differential family size and missing data. Our simulation study showed that mLRC is not affected by family size and provides more accurate selections of long-lived families. The analysis of 1105 sibships of the Historical Sample of the Netherlands showed that the selection of long-lived individuals based on the mLRC score predicts excess survival in the validation set better than the selection based on the LRC score . Conclusions Model-based score systems such as the mLRC score help to reduce heterogeneity in the selection of long-lived families. The power of future studies into the genetics of longevity can likely be improved and their bias reduced, by selecting long-lived cases using the mLRC.

External Debts and Economic Growth when Debt Rating Matters

2021 ◽  
Author(s):  
Ly Dai Hung
Keyword(s):  
Economic Growth ◽  
Growth Rate ◽  
Cross Section ◽  
Sovereign Debt ◽  
Developing Economies ◽  
External Debt ◽  
Fixed Effect ◽  
Panel Regression ◽  
Economic Growth Rate ◽  
Determinants Of Economic Growth

The paper investigates the dependence pattern of economic growth on external debt supply by accounting for the safety of debts, measured by the sovereign debt rating. The method of cross-section regression is based on a sample of 145 advanced and developing economies with averaged data over the 1990–2019 period. The pattern of economic growth follows a U-shaped curve, for which the growth rate is first decreasing and then increasing on the external debt supply. A possible explanation can rely on the sovereign debt rating. For low supply of external debts, more supply of debts reduces the debt rating, which, in turn, lowers the economic growth rate. But for high enough supply of debts, more debts raise their rating, improving the growth rate. These results are robust on controlling for various determinants of economic growth and on the fixed effect panel regression.

THE EFFECTS OF SEX AND AGE OF MALE AT CASTRATION ON GROWTH AND CARCASS QUALITY OF YORKSHIRE SWINE

1961 ◽  
Vol 41 (1) ◽  
pp. 30-39 ◽  
Author(s):  
L. A. Charette
Keyword(s):  
Growth Rate ◽  
Iodine Number ◽  
Feed Efficiency ◽  
Carcass Characteristics ◽  
Live Weight ◽  
Carcass Quality ◽  
Selection Of ◽  
Effect On Growth

The effects of sex and age of castration of males on growth rate, feed efficiency and carcass characteristics in bacon type swine were measured using 16 pigs each as gilts, entire boars, and boars castrated at birth, 6, 12, 16, and 20 weeks of age. Castration at 20 weeks was too late since some pigs reached 200 pounds live weight before that age. Boars consumed less feed daily than barrows and gilts, were thinner in loin fat, and yielded a higher percentage of shoulder than gilts. The carcasses of boars and gilts were longer, had less fat covering over the shoulder and back, a larger area of loin, and a higher iodine number than those castrated late. Acceptability tests showed that sex or age of castration did not affect the flavour, odour, or tenderness of the meat.Purebred breeders can delay castration for better selection of boars without any serious effect on growth, physical carcass characteristics, and feed requirements. Although the market discriminates against boars, it appears questionable whether castration is necessary when boars are slaughtered at 200 pounds before they reach the age of 150 days.

A Skywave OTHR Adaptive Frequency Selection Method Based on Preliminary Criterion and Weighted Criterion

2014 ◽  
Vol 1061-1062 ◽  
pp. 974-977
Author(s):  
Shi Hua Liu ◽  
Xian Gang Liu ◽  
Zhi Jian Sun
Keyword(s):  
Selection Criterion ◽  
Selection Method ◽  
Frequency Selection ◽  
Selection Of

A skywave radar adaptive frequency selection method based on the preliminary criterion and the weighted criterion is presented. In this method, according to the various operational tasks, the frequency selection criterion is divided into the preliminary criterion and the weighted criterion based on the characteristic of the targets. The adaptive frequency selection of the skywave radar is achieved by the weighted computed of the frequency selection criterion. The feasibility and availability is demonstrated by an example.

scholarly journals Altering Developmental Trajectories in Mice by Restricted Index Selection

Genetics ◽  
1997 ◽  
Vol 146 (2) ◽  
pp. 629-640
Author(s):  
William R Atchley ◽  
Shizhong Xu ◽  
David E Cowley
Keyword(s):  
Growth Rate ◽  
Body Weight ◽  
Weight Gain ◽  
Complex Traits ◽  
Body Weight Gain ◽  
Developmental Trajectories ◽  
Cell Number ◽  
Index Selection ◽  
Early Postnatal Development ◽  
Rate Of Development

A restricted index selection experiment on mice was carried out for 14 generations on rate of early postnatal development (growth rate from birth to 10 days of age) vs. rate of development much later in ontogeny (growth rate from 28 to 56 days of age). Early rate of development (E) approximates hyperplasia (changes in cell number) and later rate (L) reflects hypertropy (changes in cell size). The selection criteria were as follows: E+L0 was selected to increase early body weight gain while holding late body weight gain constant; E–L0 was selected to decrease early body gain while holding late gain constant; E0L+ was selected to increase late gain holding early gain constant; and E0L– was selected to decrease late gain holding early gain constant. After 14 generations of selection, significant divergence among lines has occurred and the changes in the growth trajectories are very close to expectation. The genetic and developmental bases of complex traits are discussed as well as the concept of developmental homoplasy.

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