scholarly journals Fast and furious . . . or not, Plk4 dictates the pace

2018 ◽  
Vol 217 (4) ◽  
pp. 1169-1171 ◽  
Author(s):  
Simon Gemble ◽  
Renata Basto
Keyword(s):  
Growth Rate ◽  
Growth Period ◽  
Balance Growth ◽  
Cell Biol ◽  
Duplication Cycle

In each duplication cycle, daughter centrioles grow to the same length as their mothers. Which mechanisms regulate this fidelity to maintain centriole length is not known. In this issue, Aydogan et al. (2018. J. Cell Biol. https://doi.org/10.1083/jcb.201801014) report a novel role for Polo-like kinase 4 (Plk4). They found that Plk4 functions in a homeostatic manner to balance growth rate and growth period to set the final centriole size.

In-Situ Dual-Wavelength Ellipsometry and Light Scattering Monitoring of Si/Si1−xGex Heterostructures and Multiuantum Wells

1993 ◽  
Vol 324 ◽  
Author(s):  
C. Pickering ◽  
D.A.O. Hope ◽  
W.Y. Leong ◽  
D.J. Robbins ◽  
R. Greef
Keyword(s):  
Growth Rate ◽  
Light Scattering ◽  
Laser Light ◽  
Growth Period ◽  
Laser Light Scattering ◽  
Heterojunction Bipolar Transistor ◽  
Dual Wavelength ◽  
Multi Quantum Well ◽  
Refractive Index Data

AbstractIn-situ dual-wavelength ellipsometry and laser light scattering have been used to monitor growth of Si/Si1−x,Gex heterojunction bipolar transistor and multi-quantum well (MQW) structures. The growth rate of B-doped Si0 8Ge0.2 has been shown to be linear, but that of As-doped Si is non-linear, decreasing with time. Refractive index data have been obtained at the growth temperature for x = 0.15, 0.20, 0.25. Interface regions ∼ 6-20Å thickness have been detected at hetero-interfaces and during interrupted alloy growth. Period-to-period repeatability of MQW structures has been shown to be ±lML.

scholarly journals The AMPK-PP2A axis in insect fat body is activated by 20-hydroxyecdysone to antagonize insulin/IGF signaling and restrict growth rate

2020 ◽  
Vol 117 (17) ◽  
pp. 9292-9301 ◽  
Author(s):  
Dongwei Yuan ◽  
Shun Zhou ◽  
Suning Liu ◽  
Kang Li ◽  
Haigang Zhao ◽  
...  
Keyword(s):  
Growth Rate ◽  
Protein Kinase ◽  
Energy Homeostasis ◽  
Molecular Mechanisms ◽  
Fat Body ◽  
Larval Growth ◽  
Growth Period ◽  
Fruit Fly ◽  
Growth Factor Signaling ◽  
Phosphatase 2A

In insects, 20-hydroxyecdysone (20E) limits the growth period by triggering developmental transitions; 20E also modulates the growth rate by antagonizing insulin/insulin-like growth factor signaling (IIS). Previous work has shown that 20E cross-talks with IIS, but the underlying molecular mechanisms are not fully understood. Here we found that, in both the silkworm Bombyx mori and the fruit fly Drosophila melanogaster, 20E antagonized IIS through the AMP-activated protein kinase (AMPK)-protein phosphatase 2A (PP2A) axis in the fat body and suppressed the growth rate. During Bombyx larval molt or Drosophila pupariation, high levels of 20E activate AMPK, a molecular sensor that maintains energy homeostasis in the insect fat body. In turn, AMPK activates PP2A, which further dephosphorylates insulin receptor and protein kinase B (AKT), thus inhibiting IIS. Activation of the AMPK-PP2A axis and inhibition of IIS in the Drosophila fat body reduced food consumption, resulting in the restriction of growth rate and body weight. Overall, our study revealed an important mechanism by which 20E antagonizes IIS in the insect fat body to restrict the larval growth rate, thereby expanding our understanding of the comprehensive regulatory mechanisms of final body size in animals.

Phenological and growth response of legume cover crops to shading

2013 ◽  
Vol 152 (6) ◽  
pp. 917-931 ◽  
Author(s):  
R. P. MAURO ◽  
O. SORTINO ◽  
M. DIPASQUALE ◽  
G. MAUROMICALE
Keyword(s):  
Growth Rate ◽  
Cover Crops ◽  
Seedling Emergence ◽  
Growth Period ◽  
Maximum Growth ◽  
Maximum Growth Rate ◽  
Cycle Duration ◽  
Cover Cropping ◽  
Future Attempt ◽  
Annual Medics

SUMMARYAnnual medics and clovers have distinct properties in terms of usage as cover crops in Mediterranean orchards, but little is known of their capacity to adapt to the level of shading encountered on an orchard floor. A 2-year field experiment was conducted in South–Eastern Sicily to investigate the effects of withholding 0·50 of sunlight on the phenology and growth pattern of four medic and five clover accessions, focusing on traits known to be important for cover cropping. Shading delayed both seedling emergence and the onset of flowering (by up to 5 and 9 days, respectively), while it extended both the growth period and the overall life-cycle duration (by up to 5 and 11 days, respectively). It also induced an increase in cover crop height (from 34 to 38 cm) and crop light use (from 0·60 to 0·94 g DW/m2/MJ), but a reduction in soil coverage, above-ground dry biomass, maximum growth rate and maximum relative growth rate (by up to 13, 18, 21 and 7%, respectively), so compromising the competitiveness of cover crops against weeds. The responses to shading varied between genotypes. Medicago polymorpha ecotype S. Rosalia, Medicago rugosa ecotype Piano Lauro and ecotype Zappulla were the strongest competitors against weeds, whereas Trifolium tomentosum ecotype Bucampello was interesting in terms of its biomass yield and crop light use. The performance was unstable over seasons, so any future attempt to improve the species’ performances under shade by breeding will need to focus on reseeding capacity.

Late Planting Effects on Early Versus Late Pearl Millet Genotypes in Niger

1993 ◽  
Vol 29 (1) ◽  
pp. 121-129 ◽  
Author(s):  
K. C. Reddy ◽  
P. L. Visser
Keyword(s):  
Growth Rate ◽  
Pearl Millet ◽  
Harvest Index ◽  
Plant Density ◽  
Pennisetum Glaucum ◽  
Growth Period ◽  
Fertilizer Application ◽  
Crop Growth ◽  
Planting Dates ◽  
Crop Growth Rate

SummaryThe performance of two contrasting pearl millet (Pennisetum glaucum) genotypes was compared following five planting dates under rainfed conditions in deep sandy soils at Bengou, Niger in 1986 and 1987. The early and partially photo-sensitive cultivar HKB yielded more grain than the late and photo-sensitive cultivar Somno when planted with the first two seasonal rains. But after delayed planting, the crop growth rate and harvest index of cultivar HKB were reduced, leading to smaller grain yields even though the growth period, rainfall, radiation and temperature were similar at all the planting dates. In contrast, cultivar Somno maintained a small but stable harvest index over various planting dates, so that although its growth period and crop growth rate were reduced by delayed planting, the reduction in grain yield was less. Since agronomic manipulation, such as increased plant density and fertilizer application, can be used to increase crop growth rate, photo-sensitive millet genotypes such as cultivar Somno could be used for late July plantings in the Sudano-Sahelian zone.

Variation in rectal temperature of cattle in a tropical environment and its relation to growth rate

1984 ◽  
Vol 38 (3) ◽  
pp. 417-427 ◽  
Author(s):  
H. G. Turner
Keyword(s):  
Growth Rate ◽  
Genetic Correlation ◽  
Rectal Temperature ◽  
Bos Indicus ◽  
Heritability Estimate ◽  
Growth Period ◽  
The Other ◽  
Tropical Environment ◽  
The Mean ◽  
Selection Of

ABSTRACTRectal temperatures of cattle grazed near the tropic of Capricorn in central Queensland were studied. The cattle were of Bos indicus, B. taurus and crossbred lines, and were represented by over 200 growing heifers in each of 2 years and some supplementary groups.Rectal temperatures were loge normally distributed when they were expressed as deviations from a basal temperature of 38°C. They were significantly repeatable, but were more highly repeatable when herd mean temperature was above 39·5°C. The heritability estimate was 0·33 (P < 0·01).The mean phenotypic regression of growth rate on rectal temperature, within breed groups, was 0·04 (s.e. 0·006) kg/day per °C (r = 0·3, P < 0·01) over the entire growth period from birth to 18 months of age but greater during warmer seasons. The estimated genetic correlation was insignificant in one group of heifers but −0·86 (s.e. 0·17) in the other.The evidence of favourable and possible unfavourable responses to selection of cattle for low rectal temperature in warm environments is discussed.

scholarly journals Effect of iodine deficiency on the reproductive performance of female rats and the viability and growth rate of their progeny

1970 ◽  
Vol 42 (2) ◽  
pp. 137-145
Author(s):  
Vappu Kossila ◽  
Ritva Myllymaa
Keyword(s):  
Growth Rate ◽  
Iodine Deficiency ◽  
Growth Period ◽  
Normal Growth ◽  
The Body ◽  
Female Rats ◽  
Deficient Diet ◽  
Adult Rats ◽  
Commercial Diet ◽  
Body Tissues

The experimental period was apparently too short and the number of rats too small to demonstrate a significant effect of iodine deficiency on some indices of reproduction of the females and the growth rate of their progeny. It was found, however, that iodine deficiency: a) delayed significantly the conception of the second generation females (C2) (Table 3) but was quite ineffective in the first generation females (B1, C1) (Tables 2 & 4), b) did not significantly affect the number of pups dropped or their birth weight, c) increased pup mortality during suckling period, d) tended to decrease the weight of the female sex organs of adult rats (Table 5), e) increased the absolute thyroid weight more rapidly in young growing rats than in old fullgrown rats (Tables 3, 4 & 5), and more rapidly in growing males than females, f) decreased significantly and progressively the PBI level in the serum of adult females which had pregnancies and lactations, g) obviously adversely affected the milk secretion of C1 rats during their second lactation on iodine deficient diet (Experiment II) as judged from the growth rate of their pups during 0—15 days after birth, h) did not adversely affect the growth rate of the suckling offspring of the dams during their first lactation on iodine deficient diet (Tables 3 & 4), i) did not significantly affect the rate of gain of the young rats from weaning up to 60-days of age. The rats transferred from iodine deficient to commercial diet at weaning had larger body weights and smaller thyroids at the age of 60 days than their litter mates remaining on an iodine deficient diet (Table 4). There is of course a possibility that the commercial diet was more palatable than the semisynthetic diet. It is also possible that the iodine deficiency activated the thyroid during the preweaning period and that after the transfer to iodine containing commercial diet at weaning, more thyroxine was secreted from preactivated glands compared to thyroids of the controls or thyroids of the rats kept on an iodine deficident diet throughout the growth period. Thyroid hormones are required for normal growth. A hypothyroid condition favours the accumulation of water and fat into the body tissues and may by this way result in an increase of the body weight. ln this study, however, no attempt was made to estimate the fat content of the body of the experimental rats.

scholarly journals Research on the Growth Mechanism of PM2.5 in Central and Eastern China during Autumn and Winter from 2013–2020

Atmosphere ◽  
2022 ◽  
Vol 13 (1) ◽  
pp. 134
Author(s):  
Qi Jiang ◽  
Hengde Zhang ◽  
Fei Wang ◽  
Fei Wang
Keyword(s):  
Growth Rate ◽  
Particulate Matter ◽  
Growth Mechanism ◽  
Fine Particles ◽  
Eastern China ◽  
Regional Scale ◽  
Growth Period ◽  
Aerosol Composition ◽  
Huai River ◽  
Autumn And Winter

Haze is a majorly disastrous type of weather in China, especially central and eastern of China. The development of haze is mainly caused by highly concentrated fine particles (PM2.5) on a regional scale. Here, we present the results from an autumn and winter study conducted from 2013 to 2020 in seven highly polluted areas (27 representative stations) in central and eastern China to analyze the growth mechanism of PM2.5. At the same time, taking Beijing Station as an example, the characteristics of aerosol composition and particle size in the growth phase are analyzed. Taking into account the regional and inter-annual differences of fine particles (PM2.5) distribution, the local average PM2.5 growth value of the year is used as the boundary value for dividing slow, rapid, and explosive growth (only focuses on the hourly growth rate greater than 0). The average value of PM2.5 in the autumn and winter of each regional representative station shows a decreasing trend as a whole, especially after 2017, whereby the decreasing trend was significant. The distribution value of +ΔPM2.5 (PM2.5 hourly growth rate) in the north of the Huai River is lower than that in the south of the Huai River, and both of the +ΔPM2.5 after 2017 showed a significant decreasing trend. The average PM2.5 threshold before the explosive growth is 70.8 µg m−3, and the threshold that is extremely prone to explosive growth is 156 µg m−3 to 277 µg m−3 in north of the Huai River. For the area south of the Huai River, the threshold for PM2.5 explosive growth is relatively low, as a more stringent threshold also puts forward stricter requirements on atmospheric environmental governance. For example, in Beijing, the peak diameters gradually shift to larger sizes when the growth rate increases. The number concentration increasing mainly distributed in Aitken mode (AIM) and Accumulation mode (ACM) during explosive growth. Among the various components of submicron particulate matter (PM1), organic aerosol (OA), especially primary OA (POA), have become one of the most critical components for the PM2.5 explosive growth in Beijing. During the growth period, the contribution of secondary particulate matter (SPM) to the accumulated pollutants is significantly higher than that of primary particulate matter (PPM). However, the proportion of SPM gradually decreases when the growth rate increases. The contribution of the PPM can reach 48% in explosive growth. Compared to slow and rapid growth, explosive growth mainly occurs in the stable atmosphere of higher humidity, lower pressure, lower temperature, small winds, and low mixed layers.

scholarly journals Modelling the growth of the brown frog (Rana dybowskii)

PeerJ ◽  
2018 ◽  
Vol 6 ◽  
pp. e4587 ◽  
Author(s):  
Qing Tong ◽  
Xiao-peng Du ◽  
Zong-fu Hu ◽  
Li-yong Cui ◽  
Hong-bin Wang
Keyword(s):  
Growth Rate ◽  
Body Weight ◽  
Body Size ◽  
Management Strategies ◽  
Growth Period ◽  
The Body ◽  
Order Polynomial ◽  
Polynomial Models ◽  
Brown Frog ◽  
Rana Dybowskii

Well-controlled development leads to uniform body size and a better growth rate; therefore, the ability to determine the growth rate of frogs and their period of sexual maturity is essential for producing healthy, high-quality descendant frogs. To establish a working model that can best predict the growth performance of frogs, the present study examined the growth of one-year-old and two-year-old brown frogs (Rana dybowskii) from metamorphosis to hibernation (18 weeks) and out-hibernation to hibernation (20 weeks) under the same environmental conditions. Brown frog growth was studied and mathematically modelled using various nonlinear, linear, and polynomial functions. The model input values were statistically evaluated using parameters such as the Akaike’s information criterion. The body weight/size ratio (Kwl) and Fulton’s condition factor (K) were used to compare the weight and size of groups of frogs during the growth period. The results showed that the third- and fourth-order polynomial models provided the most consistent predictions of body weight for age 1 and age 2 brown frogs, respectively. Both the Gompertz and third-order polynomial models yielded similarly adequate results for the body size of age 1 brown frogs, while the Janoschek model produced a similarly adequate result for the body size of age 2 brown frogs. The Brody and Janoschek models yielded the highest and lowest estimates of asymptotic weight, respectively, for the body weights of all frogs. TheKwlvalue of all frogs increased from 0.40 to 3.18. TheKvalue of age 1 frogs decreased from 23.81 to 9.45 in the first four weeks. TheKvalue of age 2 frogs remained close to 10. Graphically, a sigmoidal trend was observed for body weight and body size with increasing age. The results of this study will be useful not only for amphibian research but also for frog farming management strategies and decisions.

scholarly journals Growth of cell populations of the intralobular duct in the submandibular gland of the mouse during postnatal development

2002 ◽  
Vol 16 (4) ◽  
pp. 285-291 ◽  
Author(s):  
Rumio Taga ◽  
Luiz Carlos Pardini
Keyword(s):  
Growth Rate ◽  
Submandibular Gland ◽  
Proliferative Activity ◽  
Linear Regression Analysis ◽  
Growth Period ◽  
Absolute Number ◽  
Cell Populations ◽  
Postnatal Life ◽  
Morphometric Methods ◽  
Number Of Cells

The growth of cell populations of intercalated ducts (ID), striated ducts (SD) and convoluted granular tubules (CGT) of the submandibular gland of the mouse was analyzed, during the period of 14 to 84 days of postnatal life, by means of morphometric methods. The absolute number of cells in each type of duct was submitted to curve fitting by means of linear regression analysis, and the obtained equations were: y = 13.22 + 0.87x for ID cells in the growth period of 14 to 84 days; y = -18.82 + 3.69x and y = 176.03 - 1.93x for SD cells in the periods of growth and decay of cells, from 14 to 35 and 35 to 84 days, respectively; and y = 90.59 + 4.60x for CGT cells in the growth period of 28 to 84 days. Based on these equations, the daily accumulation (growth rate) or loss (decaying rate) of cells in the period covered by each equation was calculated. Thus, the rate of growth of ID cells was 0.87 x 10(5) cells/day; the growth and decline rates of SD cells were 3.69 x 10(5) cells/day and -1.93 x 10(5) cells/day, respectively; and the growth rate of CGT cells was 4.60 x 10(5) cells/day. The analysis of the accumulation or loss of cells and the balance of cell populations in the various types of ducts revealed that SD cells were transformed into CGT cells and that the growth of these cells’ population also depends on the formation of new cells through proliferative activity, probably in the intercalated ducts.

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