Early ontogeny of seedlings of Pinus radiata

1972 ◽  
Vol 50 (11) ◽  
pp. 2381-2387 ◽  
Author(s):  
Richard T. Riding
Keyword(s):  
Seed Coat ◽  
Pinus Radiata ◽  
Low Frequency ◽  
Maximum Size ◽  
Early Ontogeny ◽  
Axillary Bud ◽  
Minimum Size ◽  
Storage Products ◽  
Bud Initiation ◽  
Needle Primordia

The pattern of branching in seedlings of Pinus radiata appeared to be correlated with the size and zonation of the shoot apex. Just before splitting of the seed coat, the apex reached a maximum size and granular storage products, present in the embryo, were no longer evident. Shortly after the seed coat split, the hypocotyl and cotyledons became green. The first needle primordia were formed alternate to the cotyledons. Zonation of the apex was evident at this time; however, the apical zone was homogeneous and cells of the pith–rib-meristem had not elongated. Buds were initiated in the axils of many of the first-formed needle primordia. Needle initiation progressed rapidly up the flanks of the apex, reducing it to a minimum size shortly after the cotyledons emerged from the seed coat. Nodes formed at this time had a low frequency of axillary bud formation. During early epicotyl elongation the rate of needle initiation decreased and cell divisions were evident throughout the apex. The apex then increased in size and developed a zonation similar to that found in mature plants. As the apex increased in size, the frequency of axillary bud initiation also increased.

Observations on the Relations among Occlusion Effect, Compliance, and Vent Size

2002 ◽  
Vol 13 (01) ◽  
pp. 025-037 ◽  
Author(s):  
Roberto Carle ◽  
Søren Laugesen ◽  
Claus Nielsen
Keyword(s):  
Hearing Loss ◽  
Simple Model ◽  
Laboratory Experiment ◽  
Hearing Aid ◽  
Low Frequency ◽  
Minimum Size ◽  
Similar Relationship ◽  
Profound Influence ◽  
Occlusion Effect ◽  
Clinical Experiment

In a clinical experiment, it was found that there is a high correlation between the compliance measured by tympanometry and the minimum size of the earmold vent, which just solves the client's occlusion problem related to his/her own voice when using a hearing aid. For ears with sensorineural hearing losses, compliance explained 59 percent of the variation in vent size, whereas the average low-frequency hearing loss explained as little as 0.3 percent. In a laboratory experiment, the objective occlusion effect measured with the participants' own voices showed a similar relationship with compliance. Whereas the former relationship between compliance and vent size may be explained by a simple model, the latter relationship turns out to be the opposite of what a firstorder model predicts. Hence, compliance must be indicative of another aspect of the occlusion mechanism, which has a more profound influence on the observed occlusion effect than compliance itself.

Inductive graph invariants and approximation algorithms

2021 ◽  
Author(s):  
C. R. Subramanian
Keyword(s):  
Optimization Problems ◽  
Independence Number ◽  
Optimal Solution ◽  
Maximum Size ◽  
Chordal Graphs ◽  
Minimum Size ◽  
Optimal Size ◽  
Induced Subgraph ◽  
Special Cases ◽  
Optimal Formula

We introduce and study an inductively defined analogue [Formula: see text] of any increasing graph invariant [Formula: see text]. An invariant [Formula: see text] is increasing if [Formula: see text] whenever [Formula: see text] is an induced subgraph of [Formula: see text]. This inductive analogue simultaneously generalizes and unifies known notions like degeneracy, inductive independence number, etc., into a single generic notion. For any given increasing [Formula: see text], this gets us several new invariants and many of which are also increasing. It is also shown that [Formula: see text] is the minimum (over all orderings) of a value associated with each ordering. We also explore the possibility of computing [Formula: see text] (and a corresponding optimal vertex ordering) and identify some pairs [Formula: see text] for which [Formula: see text] can be computed efficiently for members of [Formula: see text]. In particular, it includes graphs of bounded [Formula: see text] values. Some specific examples (like the class of chordal graphs) have already been studied extensively. We further extend this new notion by (i) allowing vertex weighted graphs, (ii) allowing [Formula: see text] to take values from a totally ordered universe with a minimum and (iii) allowing the consideration of [Formula: see text]-neighborhoods for arbitrary but fixed [Formula: see text]. Such a generalization is employed in designing efficient approximations of some graph optimization problems. Precisely, we obtain efficient algorithms (by generalizing the known algorithm of Ye and Borodin [Y. Ye and A. Borodin, Elimination graphs, ACM Trans. Algorithms 8(2) (2012) 1–23] for special cases) for approximating optimal weighted induced [Formula: see text]-subgraphs and optimal [Formula: see text]-colorings (for hereditary [Formula: see text]’s) within multiplicative factors of (essentially) [Formula: see text] and [Formula: see text] respectively, where [Formula: see text] denotes the inductive analogue (as defined in this work) of optimal size of an unweighted induced [Formula: see text]-subgraph of the input and [Formula: see text] is the minimum size of a forbidden induced subgraph of [Formula: see text]. Our results generalize the previous result on efficiently approximating maximum independent sets and minimum colorings on graphs of bounded inductive independence number to optimal [Formula: see text]-subgraphs and [Formula: see text]-colorings for arbitrary hereditary classes [Formula: see text]. As a corollary, it is also shown that any maximal [Formula: see text]-subgraph approximates an optimal solution within a factor of [Formula: see text] for unweighted graphs, where [Formula: see text] is maximum size of any induced [Formula: see text]-subgraph in any local neighborhood [Formula: see text].

Morphological and anatomical development in the Vitaceae. I. Vegetative development in Vitis riparia

1988 ◽  
Vol 66 (2) ◽  
pp. 209-224 ◽  
Author(s):  
Jean M. Gerrath ◽  
Usher Posluszny
Keyword(s):  
Natural Populations ◽  
Three Dimensional ◽  
Leaf Primordia ◽  
Axillary Bud ◽  
Vegetative Development ◽  
Histological Techniques ◽  
Vitis Riparia ◽  
Bud Initiation ◽  
First Time ◽  
Very High

The vegetative development of natural populations of Vitis riparia is reported in detail for the first time, using a combination of three-dimensional and histological techniques. The initiation of both uncommitted primordia (which can develop into either inflorescences or tendrils) and leaf primordia is documented and correlated with their position in the primordium initiation cycle. There are four possible states: (i) a leaf at a lower tendril node, which arises on the flank of a dome-shaped apex directly above a leaf; (ii) a leaf at either an upper tendril node or a tendrilless node, which arises on the flank of a broad apex directly above a tendril; (iii) a lower uncommitted primordium, which arises very high on the apical flank, separated from the subjacent leaf by the initiation of one primordium on the opposite side of the apex; and (iv) an upper uncommitted primordium, which arises on the apical flank, separated from the subjacent leaf by the initiation of two primordia on the opposite side of the apex. This study shows that there is evidence to support the view that the uncommitted primordium is both terminal and lateral. We have extended the reports of the presence of tendril hydathodes in Vitis to this species. Axillary bud initiation and development are the same as has been reported for other species of Vitis, with each winter bud being initiated in the axil of the basal prophyll of the previous one.

scholarly journals 204 ASSOCIATION BETWEEN SOME ULTRASONIC CHARACTERISTICS OF CORPUS LUTEUM ANDPROGESTERONE VALUES IN CASPIAN MINIATURE MARES

2005 ◽  
Vol 17 (2) ◽  
pp. 252
Author(s):  
F. Gharagozloo ◽  
A. Shirazi
Keyword(s):  
Corpus Luteum ◽  
Maximum Size ◽  
Wave Pattern ◽  
Repeated Measure ◽  
Minimum Size ◽  
Blood Collection ◽  
Hormonal Changes ◽  
Estrus Cycle ◽  
Plasma Progesterone ◽  
Caspian Miniature Horse

Reproductive characteristics of the Caspian miniature horse have some similarities to other equine breeds, but several differences such as follicular wave pattern, multiple ovulations, and the size of ovulatory follicle have been reported. Still there are some other characteristics to be determined. This study was carried out to investigate ultrasonic and hormonal changes of the Caspian mares during estrus cycle. Eleven clinically healthy and cycling Caspian mares, aged 3–17 years and weighing 159–236 kg L.W., were used from April to July. Using an ultrasound scanner equipped with a 5-MHz, B-mode, linear array rectal transducer, formation of the corpus luteum was observed from Day 0 (day of ovulation), and changes in plasma progesterone were investigated by daily blood collection and assay by means of an RIA method. Repeated measure ANOVA test was used for statistical analysis. The maximum size of the corpus luteum was seen at Day 3 postovulation (36.6 ± 1.91 mm), and remained up to 10 days after ovulation. At Days 10–11 a significant decrease in size was observed; thereafter gradual regression occurred and minimum size was reached by Days 16–17 (17.3 ± 1.46 and 16.9 ± 1.20 mm, respectively). The first significant increase in progesterone level was detected 24 h after ovulation and average high values of 8 ng/mL by Day 4 after ovulation. The average peak value of progesterone was detected on Days 7 to 10 of the cycle (11.6 ± 1.37 ng/mL) and remained so until Day 12. The lowest plasma progesterone concentration (less than 1 ng/mL) was observed from Day 14 till one day postovulation, coinciding with the CL regression found in sonographic observations. The results of this study revealed that the pattern of corpus luteum formation and Its changes in size and the plasma progesterone levels during the estrus cycle in this breed follow a pattern similar to that of other equine breeds. The authors wish to thank the University of Tehran for funding and Khojir stud farm for providing animals.

scholarly journals Competition and growth in Aedes aegypti larvae: effects of distributing food inputs over time

2020 ◽  
Author(s):  
Kurt Steinwascher
Keyword(s):  
Food Resource ◽  
Maximum Size ◽  
Bimodal Distribution ◽  
Minimum Size ◽  
Life History Strategies ◽  
Food Level ◽  
Mosquito Larvae ◽  
Male And Female ◽  
Total Food ◽  
Larval Life History

AbstractMale and female mosquito larvae compete for different subsets of the yeast food resource in laboratory microcosms. Males compete more intensely with males and females with females. The amount and timing of food inputs alters both growth and competition, but the effects are different between sexes. Increased density increases competition among males. Among females, density operates primarily by changing the food/larva or total food; this affects competition in some interactions and growth in others. Food added earlier in the life span contributes more to mass than the same quantity added later. After a period of starvation larvae appear to use some of the subsequent food input to rebuild physiological reserves in addition to building mass. The timing of pupation is affected by the independent factors and competition, but not in the same way for the two sexes, and not in the same way as mass at pupation for the two sexes. There is an effect of density on the timing of pupation for females independent of competition or changes in food/larva or total food. Male and female larvae have different larval life history strategies. Males grow quickly to a minimum size, then pupate, depending on the amount of food available. Males that do not grow quickly enough may delay pupation further to grow larger, resulting in a bimodal distribution of sizes and ages. Males appear to have a maximum size determined by the early food level. Females grow faster than males and grow larger than males on the same food inputs. Females affect the growth and competition among males by manipulating the number of particles in the microcosm through changes in feeding behavior. Mosquito larvae appear to have evolved to survive periods of starvation and take advantage of intermittent inputs of food into containers.

scholarly journals Anatomical Differences of Axillary Bud Development in Blind Nodes and Normal Nodes in Peach

HortScience ◽  
1996 ◽  
Vol 31 (5) ◽  
pp. 798-801 ◽  
Author(s):  
Unaroj Boonprakob ◽  
David H. Byrne ◽  
Dale M.J. Mueller
Keyword(s):  
Prunus Persica ◽  
Growing Season ◽  
Axillary Bud ◽  
Early Season ◽  
Bud Development ◽  
Late Season ◽  
Bud Initiation ◽  
Node Formation

Actively growing shoots of peach [Prunus persica (L.) Batsch] were collected every 2 weeks throughout the 1989 growing season. The samples were sectioned longitudinally and transversely to observe axillary bud initiation, which occurred in all samples collected. Differentiation of axillary bud meristems from early season samples (mostly normal nodes) included apical and prophyll formation, with procambium connected to the stem procambium. Little to no differentiation of such structures occurred in the late-season samples (mostly blind nodes). Other results suggest that blind node formation is a consequence of a lack of bud differentiation rather than a failure of bud initiation.

Effects of Security Design of Asset-Backed Securities on the Value of Asset-Backed Securities and the Value of Issuing Firm

2005 ◽  
Vol 13 (2) ◽  
pp. 1-37
Author(s):  
Jin Yoo
Keyword(s):  
Information Asymmetry ◽  
Maximum Size ◽  
Minimum Size ◽  
Security Design ◽  
Asset Portfolio ◽  
Asset Backed Securities

Security design of asset-backed securities (ABS) could affect the value of the ABS and that of the issuing firm as well when there exists an information asymmetry between insiders and outsiders of the firm, depending on the size of the assets sold. If the size is relatively small, the optimal security design will be such that the firm sells the risk-free, senior security (backed by the asset sold) to outsiders at a minimum size and retains the risky, subordinate security. If the size is large, the firm should sell outsiders both the risk-free security at a maximum size and the risky tranche at a minimum size. Meanwhile, if the firm has to sell an asset portfolio rather than an asset, the firm is better off by selling the portfolio through bundling the assets of the portfolio. It turns out that the bundling into senior and subordinate tranches is preferred to the bundling and selling to outsiders.

WIDEN: A tool for medical imaging management in oncology clinical trials.

2012 ◽  
Vol 30 (15_suppl) ◽  
pp. e13093-e13093
Author(s):  
Stephane Chauvie ◽  
Alberto Biggi ◽  
Alexandru Stancu ◽  
Piergiorgio Cerello ◽  
Andrea Gallamini
Keyword(s):  
Clinical Trial ◽  
Medical Imaging ◽  
Median Time ◽  
Low Cost ◽  
Maximum Size ◽  
Response Assessment ◽  
Time Frame ◽  
Pet Scan ◽  
Minimum Size ◽  
Case Review

e13093 Background: Recently a novel clinical trial generation based on a therapeutic strategy driven by early treatment response assessment to therapy by functional imaging was conceived and a central review of the images became necessary. We describe hear the application of a new web-based tool for imaging exchange and online review of PET scan (WIDEN) conceived for the prospective multicenter clinical trial HD0607. Methods: In the HD 0607 clinical trial 367 patients affected by advanced-stage Hodgkin Lymphoma (HL), are treated with 2 ABVD courses and a PET scan performed afterwards (PET-2). PET-2 positive patients shift to an aggressive treatment, PET-2 negative patients continue with ABVD. PET-2 along with the baseline scan (PET-0) is uploaded to a dedicated web site thanks to WIDEN and hence distributed to six expert reviewers. The latter report the scans within 72 hours from the upload and determine the choice whether intensify or not the treatment intensity (NCT identifier 00795613). Results: The average (median) time per scan upload and download were 6’39” (1’35”) and 3’26” (1’53”) respectively. The average (median) PET scan size were 133.8 MB (121.5 MB), with a minimum size of 51.2 MB and a maximum size of 469.8 MB. The average (median) time frame between the case files upload by the submitting centre and the case review reporting was 48h 45‘ (40h 31’). 7% of the cases were reviewed among the forth and the fifth days. 3% cases were reviewed after the fifth days. In all cases of a review time spanning over more than three days the delay depended on the presence of a week-end of other holiday time. Concordance rate among reviewers measured with Krippendorff,s alpha was 0.799. Conclusions: WIDEN proved to be an effective tool for medical imaging exchange and review. Data security, simplicity, low cost, feasibility and prompt scan review were demonstrated. Its applicability in any clinical trial in which imaging is decisional for treatment modulation is warranted

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