Xylogénèse chez les Dicotylédones arborescentes. IV. Influence des bourgeons, de l'acide (β-indolyl acétique et de l'acide gibberellique sur la réactivation cambiale et la xylogénèse dans les jeunes tiges de Hêtre

1983 ◽  
Vol 61 (6) ◽  
pp. 1768-1774 ◽  
Author(s):  
Suzanne Lachaud
Keyword(s):  
Transport System ◽  
Short Distance ◽  
Auxin Transport ◽  
Cambial Activity ◽  
Long Distance ◽  
Cambial Reactivation

The application, in the middle of April, of a mixture of IAA (10−4 M) and GA3 (10−4 M), to apical stem of young beeches, disbudded more than 1 month ago, brings about the formation of an unusual early wood, composed of small xylary elements only, on a short distance. If the phytohormones are applied immediately on the following day after disbudding, the young trees produce normal early wood, on a long distance. GA3 applied alone has hardly any effect on cambial reactivation; IAA applied alone stimulates less cambial reactivation and xylogenesis than the mixture of IAA and GA3. The study of [3H]-IAA transport in apical shoots of the same trees shows that beeches disbudded 1 month ago have lost the ability to activate the auxin transport. Disbudding, carried out in the middle or at the end of the preactivation phase, affects the IAA transport system within a few days; a further exogenous phytohormone application cannot then replace buds and promote the renewal of cambial activity. In young beeches, the resumption of tissue ability to polarize the auxin transport, which in February characterizes the beginning of the preactivation phase, depends on buds; the maintenance and development of this ability are related to their presence.

Effects of auxin-transport-inhibitor and defoliation on wood formation in locally-heated Abies homolepis

IAWA Journal ◽  
2018 ◽  
Vol 39 (4) ◽  
pp. 353-371 ◽  
Author(s):  
Md Hasnat Rahman ◽  
Kayo Kudo ◽  
Shahanara Begum ◽  
Yusuke Yamagishi ◽  
Takahiro Muraishi ◽  
...  
Keyword(s):  
Auxin Transport ◽  
Cambial Activity ◽  
Wood Formation ◽  
Limiting Factors ◽  
Endogenous Factors ◽  
Continuous Formation ◽  
Transport Inhibitor ◽  
Cambial Reactivation ◽  
Abies Homolepis ◽  
Auxin Transport Inhibitor

ABSTRACTTo understand the precise process of wood formation, it is necessary to identify the factors that regulate cambial activity and development of cambial derivatives. Here, we investigated the combined effects of localized-heating and auxin on cambial reactivation and the formation of earlywood tracheids in seedlings of the evergreen coniferAbies homolepisin winter. Three treatments were applied, namely heating (artificial increase in temperature 20–22 °C), heating-plus-auxin transport inhibitor N-(1-naphthyl) phthalamic acid (NPA) and heating-plus-defoliation (removal of needles and buds), with an approximate control, for investigations of cambial activity by light microscopy. After one week of heating, cambial reactivation occurred in the heating, heating-plus-NPA and heating-plus-defoliation treatments. In untreated controls, cambial reactivation occurred later than in heated stems. Earlywood tracheids were formed after three and six weeks of heating in the heating and heating-plus-NPA treatments, respectively. No tracheids were formed after eight weeks of heating in heated-defoliated seedlings. Numbers of new tracheids were reduced in heated stems by NPA. Our results suggest that an increase in the temperature of the stem is one of the most important limiting factors in cambial reactivation, which is independent of needles and buds and of the polar transport of auxin from apical sources. However, after cambial reactivation, initiation and continuous formation of earlywood tracheids require basipetally transported auxin and other endogenous factors originating in mature needles and buds.

scholarly journals K → μ+μ− as a clean probe of short-distance physics

2021 ◽  
Vol 2021 (7) ◽  
Author(s):  
Avital Dery ◽  
Mitrajyoti Ghosh ◽  
Yuval Grossman ◽  
Stefan Schacht
Keyword(s):  
Matrix Element ◽  
Standard Model ◽  
Short Distance ◽  
Time Dependent ◽  
Final States ◽  
Interference Effects ◽  
Fundamental Theory ◽  
Long Distance ◽  
Ckm Matrix ◽  
The Standard Model

Abstract The K → μ+μ− decay is often considered to be uninformative of fundamental theory parameters since the decay is polluted by long-distance hadronic effects. We demonstrate that, using very mild assumptions and utilizing time-dependent interference effects, ℬ(KS → μ+μ−)ℓ=0 can be experimentally determined without the need to separate the ℓ = 0 and ℓ = 1 final states. This quantity is very clean theoretically and can be used to test the Standard Model. In particular, it can be used to extract the CKM matrix element combination $$ \mid {V}_{ts}{V}_{td}\sin \left(\beta +{\beta}_s\right)\mid \approx \mid {A}^2{\lambda}^5\overline{\eta}\mid $$ ∣ V ts V td sin β + β s ∣ ≈ ∣ A 2 λ 5 η ¯ ∣ with hadronic uncertainties below 1%.

scholarly journals The impact of some morphological and motor characteristics in short distance running

2021 ◽  
Vol 11 (6) ◽  
pp. 109-119
Author(s):  
Q. Ramabaja ◽  
N. Rashiti ◽  
M. Shkodra ◽  
L. Ramadani
Keyword(s):  
Physical Education ◽  
Motor Skills ◽  
Short Distance ◽  
Morphological Development ◽  
Strong Impact ◽  
Distance Running ◽  
Anthropometric Parameters ◽  
Long Distance ◽  
Anthropometric Characteristics ◽  
The Impact

The knowledge of morphological development and their impact on motor skills in short-distance athletes should be one of the main concerns of athletics coaches, because any scientific research in the field of physical culture and sports is about proving the development and evaluation of anthropological characteristics which are responsible for achieving success in athletics. The purpose of this paper is to confirm the impact of some anthropometric characteristics in the execution of running speeds on short distances, specifically in running at 100, 200 and 400 meters to students aged 18 ± 6 years of the Faculty of Physical Education and Sports in Prishtina. The sample of this research has included a total of 60 students aged 18 years of the Faculty of Physical Education and Sports in Prishtina. The measurements were executed during September in the hall of the Faculty, while the 100, 200, and 400 meter runs in the stadium "Fadil Vokrri" Prishtina. The only condition that was used during the determination of the sample was: that the students are involved in regular physical education classes (and on the day of the measurement be healthy, without the flu, cold or other symptoms). The variables which are applied in this research have been 8 anthropometric variables and 3 motor-specific variables. The results obtained after their processing indicate that the impact of anthropometric variables is higher in running at 100, 200 and 400 meters. Short distance running and long distance running reduces the impact of anthropometric parameters whereas the influence of metabolic factors of energy production is increased.  These results were also confirmed using regression analysis, so that groups of predictors of anthropometric characteristics, specific motor skills that statistically significantly influenced each variable of individual criteria. The world records below the 10-second limit, in the 100 m, near the 9-meter limit, show not only the high level of sports, but also the strong impact on the growth, especially of strength indicators, speed-strength, explosive force, as main and applied motor skills in sports and athlete’s everyday life.

Effect of cambial dormancy state on the transport of [1-14C]indol-3-ylacetic acid in Abies balsamea shoots

1981 ◽  
Vol 59 (3) ◽  
pp. 342-348 ◽  
Author(s):  
C. H. A. Little
Keyword(s):  
Abies Balsamea ◽  
Cambial Activity ◽  
Controlled Environment ◽  
Long Distance ◽  
Dormant Period ◽  
Cambial Zone ◽  
Time Required ◽  
Ylacetic Acid ◽  
Exogenous Iaa

Dormant attached or detached shoots of balsam fir were naturally or artificially chilled to induce different states along the rest–quiescence continuum. At the end of the chilling pretreatment, the shoots either were left intact or were debudded and treated with indol-3-ylacetic acid (IAA). The shoots were placed under controlled-environment conditions favorable for growth, and at intervals thereafter, a pulse of [1-14C]IAA was applied to the shoot apex. Measured at the end of the chilling pretreatment, [14C]IAA velocity and flux decreased with increasing duration of chilling (i.e., as rest graded into quiescence). The time required to commence cambial growth and to attain maximum rates of cambial activity and [14C]IAA transport also decreased as rest changed to quiescence. Transport in actively growing shoots exceeded that in quiescent shoots, but was similar to that in resting shoots. The [14C]IAA pulse moved basipetally as unchanged IAA, was blocked by a bark + cambium girdle, and was inhibited by abscisic acid and long-term application of exogenous IAA. The results indicate that: (1) the long-distance, cambium-located, IAA transport system demonstrated in dicotyledonous species also operates in conifers, (2) during the dormant period changes occur in [14C]IAA transport and in the cambial response to exogenous IAA, (3) the change in [14C]IAA transport is the result of change in the transporting capability of cells in the cambial zone, and (4) the change in [14C]IAA transport is not the cause of the differential response of quiescent and resting cambia to exogenous IAA.

scholarly journals Job Accessibility from a Multiple Commuting Circles Perspective Using Baidu Location Data: A Case Study of Wuhan, China

2019 ◽  
Vol 11 (23) ◽  
pp. 6696 ◽  
Author(s):  
Cai ◽  
Liu ◽  
Luo ◽  
Xing ◽  
Liu
Keyword(s):  
Urban Areas ◽  
Short Distance ◽  
Long Distance ◽  
Job Accessibility ◽  
Location Data ◽  
Job Opportunities ◽  
Transit Services ◽  
Service Jobs ◽  
Wuhan Metropolitan Area

Jobs–housing imbalance is a hot topic in urban study and has obtained many results. However, little research has overcome the limits of administrative boundaries in job accessibility measurement and considered differences in job accessibility within multiple commuting circles. Using Baidu location data, this research proposes a new method to measure job accessibility within multiple commuting circles at the grids’ level. Taking the Wuhan metropolitan area as a case study, the results are as follows: (1) Housing and service jobs are concentrated in the central urban areas along the Yangtze River, whereas industrial jobs are scattered throughout suburbs with double centers. The potential competition for job opportunities is fiercer in the city center than in the suburbs. (2) Job accessibility with different levels shows significant circle-like distribution. People with long- or short-distance potential commutes demand to live close to the groups with the same demand. Residents with long-distance commutes demand to live outside of where those with short-distance commutes demand to reside, regardless of whether their commuting demand is for service or industrial jobs. (3) There are three optimization patterns for transit services to increase job accessibility in various areas. These patterns involve areas with inadequate job opportunities, poor transit services to service jobs, and poor transit services to industrial jobs. Developing current transit facilities or new transit alternatives as well as adding extra jobs near housing could improve jobs–housing imbalance in these areas. Findings from this study could guide the allocation of jobs and housing as well as the development of transport to reduce residents’ commuting burdens and promote transportation equity. The method used in this study can be applied to evaluate jobs–housing imbalance from the perspective of the supply in other metropolises.

scholarly journals Increased EEG coherence in long‐distance and short‐distance connectivity in children with autism spectrum disorders

2020 ◽  
Vol 10 (10) ◽  
Author(s):  
Jia Wang ◽  
Xiaomin Wang ◽  
Xuelai Wang ◽  
Huiying Zhang ◽  
Yong Zhou ◽  
...  
Keyword(s):  
Autism Spectrum Disorders ◽  
Short Distance ◽  
Children With Autism ◽  
Autism Spectrum ◽  
Eeg Coherence ◽  
Long Distance ◽  
Spectrum Disorders

scholarly journals Exploring Monitoring Systems Data for Driver Distraction and Drowsiness Research

Sensors ◽  
2020 ◽  
Vol 20 (14) ◽  
pp. 3836
Author(s):  
António Lobo ◽  
Sara Ferreira ◽  
António Couto
Keyword(s):  
Short Distance ◽  
Monitoring Systems ◽  
Mobility Patterns ◽  
Long Distance ◽  
Road Crashes ◽  
Driving Time ◽  
Driver Monitoring ◽  
Driver Inattention ◽  
Ordered Probit Models ◽  
Breaking Time

Driver inattention is a major contributor to road crashes. The emerging of new driver monitoring systems represents an opportunity for researchers to explore new data sources to understand driver inattention, even if the technology was not developed with this purpose in mind. This study is based on retrospective data obtained from two driver monitoring systems to study distraction and drowsiness risk factors. The data includes information about the trips performed by 330 drivers and corresponding distraction and drowsiness alerts emitted by the systems. The drivers’ historical travel data allowed defining two groups with different mobility patterns (short-distance and long-distance drivers) through a cluster analysis. Then, the impacts of the driver’s profile and trip characteristics (e.g., driving time, average speed, and breaking time and frequency) on inattention were analyzed using ordered probit models. The results show that long-distance drivers, typically associated with professionals, are less prone to distraction and drowsiness than short-distance drivers. The driving time increases the probability of inattention, while the breaking frequency is more important to mitigate inattention than the breaking time. Higher average speeds increase the inattention risk, being associated with road facilities featuring a monotonous driving environment.

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