scholarly journals Scaling and structural properties of juvenile bull kelp (Nereocystis luetkeana)

2021 ◽  
Author(s):  
Katie A Dobkowski ◽  
Stephanie B Crofts
Keyword(s):  
Structural Properties ◽  
Maximum Stress ◽  
Size Range ◽  
Life Stages ◽  
Allometric Growth ◽  
Cross Sectional ◽  
Important Species ◽  
Subtidal Environment ◽  
Nereocystis Luetkeana ◽  
Stipe Length

Abstract Bull kelp (Nereocystis luetkeana), the only canopy-forming kelp in the Salish Sea, provides primary production in the nearshore subtidal environment and serves as important habitat for economically and ecologically important species. An annual species, each year juvenile bull kelp sporophytes must grow from the hydrodynamically more benign benthos to the water column, where they experience substantial drag at the surface. Because of the differences in morphology and ecology across life stages, and the fact that previous work has focused mainly on adult bull kelp, we tested whether morphology and structural properties change with stipe length, investigating scaling of both juvenile (stipe length < 40 cm) and mature (stipe length > 40cm) kelp, and testing how juvenile stipes fail. Juvenile bull kelp grow proportionally (isometric growth) when young, but lengthen more quickly than would be predicted by bulb size (negative allometry) at maturity. Based on our data, the predicted breakpoint between isometric and allometric growth occurred at about 33 cm, likely ∼ one to two weeks of growth. Cross sectional area of the stipe, Force to failure, Work to failure, and stiffness (Young's Modulus) all grow more slowly than would be predicted based on length, while Maximum Stress and Toughness increase more quickly than predicted. There is no change in extensibility over the size range we tested, suggesting that this material property does not change with stipe length. The differences in biomechanics between juvenile and adult kelp are likely a response to the varied hydrodynamic environments experienced during the annual lifecycle, which highlights the importance of studying organisms across life stages.

The Effects of Nitrogen on Electrical and Structural Properties in TaSixNy/SiO2/p-Si MOS Capacitors

2002 ◽  
Vol 716 ◽  
Author(s):  
You-Seok Suh ◽  
Greg Heuss ◽  
Jae-Hoon Lee ◽  
Veena Misra
Keyword(s):  
Structural Properties ◽  
Electron Spectroscopy ◽  
Oxygen Diffusion ◽  
Gate Dielectric ◽  
Barrier Properties ◽  
Reaction Rates ◽  
Cross Sectional ◽  
Mos Capacitors ◽  
Transmission Electron ◽  
Thermal Stability Of

AbstractIn this work, we report the effects of nitrogen on electrical and structural properties in TaSixNy /SiO2/p-Si MOS capacitors. TaSixNy films with various compositions were deposited by reactive sputtering of TaSi2 or by co-sputtering of Ta and Si targets in argon and nitrogen ambient. TaSixNy films were characterized by Rutherford backscattering spectroscopy and Auger electron spectroscopy. It was found that the workfunction of TaSixNy (Si>Ta) with varying N contents ranges from 4.2 to 4.3 eV. Cross-sectional transmission electron microscopy shows no indication of interfacial reaction or crystallization in TaSixNy on SiO2, resulting in no significant increase of leakage current in the capacitor during annealing. It is believed that nitrogen retards reaction rates and improves the chemical-thermal stability of the gate-dielectric interface and oxygen diffusion barrier properties.

scholarly journals Possible Selves Across the Lifespan

2020 ◽  
Vol 4 (Supplement_1) ◽  
pp. 449-449
Author(s):  
Victoria Chen ◽  
Alysson Light
Keyword(s):  
Possible Selves ◽  
Well Being ◽  
Self Concept ◽  
Life Stages ◽  
Cross Sectional Survey ◽  
Cross Sectional ◽  
Younger Adults ◽  
Midlife Adults ◽  
Age Range ◽  
The Relationship

Abstract Possible selves are defined as “personalized representations of one’s self in future states” (Cross & Markus, 1991). Research has also found that thinking frequently about possible selves predicts lower well-being, whereas thinking clearly about possible selves is associated with higher well-being (McElwee & Haugh, 2010). However, possible selves differ across the lifespan (Hooker & Kaus, 1994; Cross & Markus, 1991) and life stages can impact exploration of possible identities (Arnett, 2000). Thus we hypothesize that the relationship between thought about possible selves and well-being differs across the lifespan. In a cross-sectional survey, 240 participants (age range: 18-92) reported on frequency and clarity of possible selves, as well as general self-clarity (Campbell et al., 1996). Results indicate curvilinear moderation by age of the link between possible self-clarity and well-being, with the association being stronger among midlife adults than among younger adults and older adults. Also, as clarity of feared possible selves increases, self-concept clarity decreases. Similarly, frequency of thinking about feared possible selves was negatively correlated with self-concept clarity. However, clarity and frequency of thought about hoped-for positive possible selves had no correlation with self-concept clarity.

scholarly journals De acordo com o governador, a decisão vale para todos que estejam em condições físicas adequadas, mesmo os que ainda não tomaram a vacina contra a Covid-19

2021 ◽  
Vol 58 ◽  
pp. e181002
Author(s):  
Yudit Rodríguez Coipel ◽  
Aníbal Domínguez Odio ◽  
Odaimis Mena Álvarez ◽  
Raiselys Toirac Proenza ◽  
Isbel González Marrero ◽  
...  
Keyword(s):  
Global Market ◽  
Cross Sectional ◽  
Herbal Products ◽  
Important Species ◽  
Industrial Manufacturing ◽  
The United Kingdom ◽  
Ancestral Knowledge ◽  
Oral Formulations ◽  
Frequent Use ◽  
Animal Use

The industrial manufacturing of natural products for veterinary use represents a major weakness in the veterinary sector despite increased interest and the traditional ancestral knowledge that supports them. A cross-sectional, descriptive observational study was conducted to characterize the veterinary herbal products marketed worldwide during 2018 and 2019. A comprehensive thematic search limited to the 2018-2019 period was performed in the ScienceDirect, Scopus, PubMed, Web of Science, ResearchGate, and Academic Search Complete databases. The investigation identified 487 products registered in the global market manufactured by 54 companies, led by India, The Netherlands, and the United Kingdom. The market segments of animal production and phytomedicines were dominant with 73.7% and 53.0% of products, respectively. Cattle (22.2%), sheep-goats (16.2%), and canines (16.2%) were the most favored species. The most represented therapeutic indications were those intended to treat gastrointestinal disorders (30.47%), antimicrobials (16.66%), and antiparasitic agents (10.47%). The families Fabaceae, Lamiaceae, Asteraceae, Apiaceae, Malvaceae, and Rutaceae stood out because of their frequent use, encompassing 35.0% of the 137 declared species. Andrographis paniculata (Burm.f.) Nees and Withania somnifera (Lin) Dunal were the most important species. Oral formulations for internal use (72%) and liquids (51%) in 100 mL, 500 mL, and 1 L presentations showed the highest prevalence on the market. The global market for veterinary herbal products during the 2018-2019 period was relevant in the productive and medical animal sector. No differences were found between medicinal plant species used to formulate herbal products for human and animal use.

Morphological maturity and allometric growth in the squat lobster Munida rugosa

2009 ◽  
Vol 89 (6) ◽  
pp. 1189-1194 ◽  
Author(s):  
Thomas Claverie ◽  
I. Philip Smith
Keyword(s):  
Measurement Error ◽  
Sexual Maturity ◽  
Carapace Length ◽  
Size Range ◽  
Size At Maturity ◽  
Allometric Growth ◽  
Positive Allometry ◽  
Squat Lobster

Size at the onset of sexual maturity was determined in Munida rugosa based on allometric growth of chelipeds and abdomen, and on the proportion of ovigerous females. The variability of three different measurements of carapace length (CL) used previously for M. rugosa was also evaluated to minimize measurement error. Both sexes had symmetrical cheliped length and allometric cheliped growth over the size-range investigated, but males showed increased allometry beyond 22 mm CL. Females had greater positive allometry in abdomen width than males, but their size at maturity could not be precisely determined because sampled females were too large.

Immature stages, host plants and natural enemies of Henosepilachna implicata (Mulsant) (Coleoptera: Coccinellidae) with DNA sequence data and a new synonym and notes on some Indian species of Epilachnini

Zootaxa ◽  
2021 ◽  
Vol 4970 (3) ◽  
pp. 533-546
Author(s):  
J. POORANI ◽  
R. G. BOOTH ◽  
R. GANDHI GRACY ◽  
C. ANURADHA ◽  
R. THANIGAIRAJ ◽  
...  
Keyword(s):  
Dna Sequence ◽  
Natural Enemies ◽  
Host Plants ◽  
Sequence Data ◽  
Indian Species ◽  
Life Stages ◽  
Important Species ◽  
Dna Sequence Data ◽  
New Synonym ◽  
First Time

Life stages of Henosepilachna implicata (Mulsant), an economically important species of Epilachnini in India, are documented and illustrated. Mitochondrial DNA sequence data is provided for the first time for H. implicata with additional details on its host plants, distribution, and natural enemies. Its similarities and differences with other common pestiferous Henosepilachna spp. in India such as H. vigintioctopunctata (F.), H. septima (Dieke) and H. pusillanima (Mulsant) are discussed. Epilachna circularis Korschefsky, 1933 is found to be conspecific with H. implicata and is reduced to a junior synonym of the latter (new synonym). Notes are given on the distribution and natural enemies of some other species of Epilachnini of the Indian region.  

Myogenic and structural properties of cerebral arteries from the stroke-prone spontaneously hypertensive rat

2003 ◽  
Vol 285 (4) ◽  
pp. H1489-H1494 ◽  
Author(s):  
Ashley S. Izzard ◽  
Delyth Graham ◽  
Matthew P. Burnham ◽  
Egidius H. Heerkens ◽  
Anna F. Dominiczak ◽  
...  
Keyword(s):  
Structural Properties ◽  
Spontaneously Hypertensive Rat ◽  
Cerebral Arteries ◽  
Systolic Pressure ◽  
Cross Sectional ◽  
Spontaneously Hypertensive ◽  
Hypertensive Rat ◽  
Constant Diameter ◽  
Strain Relationship

The aims of the study were to compare the myogenic and structural properties of middle cerebral arteries (MCAs) from the stroke-prone spontaneously hypertensive rat (SHRSP) with MCAs from the spontaneously hypertensive rat (SHR) before stroke development in SHRSP. Rats were fed a “Japanese” diet (low-protein rat chow and 1% NaCl in drinking water) for 8 wk, and cerebral arteries were studied in vitro at 12 wk using a pressure arteriograph. Systolic pressure was significantly increased in SHRSP compared with SHR at 12 wk. Between 60 and 180 mmHg, MCAs from SHR maintained an essentially constant diameter, i.e., displayed a “myogenic range,” whereas the diameter of MCAs from SHRSP progressively increased as a function of pressure. Passive lumen diameter of MCAs from SHRSP was reduced at high pressure, and wall thickness and wall/lumen were increased, compared with SHR. Wall cross-sectional area was also increased in MCAs from SHRSP compared with the SHR, indicating growth. The stress-strain relationship was shifted to the left in MCAs from SHRSP, indicating decreased MCA distensibility compared with SHR. However, collagen staining with picrosirius red revealed a redistribution of collagen to the outer half of the MCA wall in SHRSP compared with SHR. These data demonstrate impaired myogenic properties in prestroke SHRSP compared with SHR, which may explain stroke development. The structural differences in MCAs from SHRSP compared with SHR were a consequence of both growth and a reduced distensibility.

scholarly journals The Effects of Annealing Temperature on the Structural Properties of ZrB2 Films Deposited via Pulsed DC Magnetron Sputtering

Coatings ◽  
2019 ◽  
Vol 9 (4) ◽  
pp. 253 ◽  
Author(s):  
Wei-Chun Chen ◽  
Chao-Te Lee ◽  
James Su ◽  
Hung-Pin Chen
Keyword(s):  
Electron Microscopy ◽  
Magnetron Sputtering ◽  
Structural Properties ◽  
Photoelectron Spectroscopy ◽  
Annealing Temperature ◽  
High Vacuum ◽  
Film Structure ◽  
Dc Magnetron Sputtering ◽  
Cross Sectional ◽  
X Ray

Zirconium diboride (ZrB2) thin films were deposited on a Si(100) substrate using pulsed direct current (dc) magnetron sputtering and then annealed in high vacuum. In addition, we discussed the effects of the vacuum annealing temperature in the range of 750 to 870 °C with flowing N2 on the physical properties of ZrB2 films. The structural properties of ZrB2 films were investigated with X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), atomic force microscopy (AFM), and X-ray photoelectron spectroscopy (XPS). The XRD patterns indicated that the ZrB2 films annealed at various temperatures exhibited a highly preferred orientation along the [0001] direction and that the residual stress could be relaxed by increasing the annealing temperature at 870 °C in a vacuum. The surface morphology was smooth, and the surface roughness slightly decreased with increasing annealing temperature. Cross-sectional TEM images of the ZrB2/Si(100) film annealed at 870 °C reveals the films were highly oriented in the direction of the c-axis of the Si substrate and the film structure was nearly stoichiometric in composition. The XPS results show the film surfaces slightly contain oxygen, which corresponds to the binding energy of Zr–O. Therefore, the obtained ZrB2 film seems to be quite suitable as a buffer layer for III-nitride growth.

The effect of oleic acid on the synthesis of Fe3−xO4 nanoparticles over a wide size range

2015 ◽  
Vol 17 (41) ◽  
pp. 27373-27379 ◽  
Author(s):  
Carlos Moya ◽  
Xavier Batlle ◽  
Amílcar Labarta
Keyword(s):  
Thermal Decomposition ◽  
Oleic Acid ◽  
Structural Properties ◽  
Acid Concentration ◽  
Size Range ◽  
Benzyl Ether ◽  
Oleic Acid Concentration ◽  
Wide Size Range

This work reports on the effect of the oleic acid concentration on the magnetic and structural properties of Fe3−xO4 nanoparticles synthesized by thermal decomposition of Fe(acac)3 in benzyl-ether.

Evaluation of Maternal Confidence in Neonatal Care Among Primiparous Pregnant Women in Sari, Iran

2020 ◽  
Author(s):  
Mahshid Ahmadi ◽  
Hamed J Jafarpour ◽  
Jaber Mousavi ◽  
Alireza Razavi
Keyword(s):  
Pregnant Women ◽  
Confidence Score ◽  
Cross Sectional Study ◽  
Neonatal Care ◽  
Life Stages ◽  
Cross Sectional ◽  
Maternal Confidence ◽  
The Mean ◽  
First Time ◽  
And Task

Introduction: The first 28 days after birth is one of the most critical neonate life stages and mother is the most important person meeting the basic needs of the baby. Besides the importance of knowledge about neonatal care maternal confidence is also important. The aim of this study was the evaluation of maternal confidence in neonatal care among primiparous pregnant women.Material and Methods: In this cross-sectional study, 445 pregnant women who experienced pregnancy for the first time and referred to maternity care centers for prenatal care were studied. The translated Chinese version of the Maternal Confidence Questionnaire to local language was used. The validity of the questionnaire was approved by three experienced pediatrics professors. Reliability of the questionnaire using the test-retest method examined, 35 pregnant women (selected from a similar setting but out of the study area). Cronbach's alpha with r = 0.81 was acceptable.Results: In this study, information about 445 women were evaluated. The mean age of the subjects was 28.39 years (SD = 4.66, range = 19 - 39). The mean (SD) of the total maternal confidence score was 58.87(3.75), Which included knowledge (21.09 ± 2.1), tasks (22.09 ± 1.8) and feelings (15.67 ± 1.17).Conclusion: Higher maternal confidence was related to knowledge and task subgroups and the feeling subgroup had the lowest score.

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