Identification and determination of growth hormones of Kappaphycus alvarezii cultivated in Ekas Bay East Lombok

The extract of red marine algae contained growth-enhancing properties which is associated to age and their morphotypes. Kappaphycus alvarezii cultured in Ekas Bay, Lombok, Indonesia was studied and aimed to determine the content of growth-promoting substances in the young and old thallus of brown and green morphotypes of K. alvarezii. The content of K. alvarezii thallus growth substances was determined by High Performance Liquid Chromatography (HPLC). This study showed that the old thallus in the brown K. alvarezii strain contained auxin 8.43 ppm and the young thallus 2.89 ppm, while the old thallus in the green strain K. alvarezii contained auxin 10.92 ppm and the young thallus contained 16.28 ppm. This study concluded that auxin was the only growth promoter detected in K. alvarezii seeds in both young and old thallus in green and brown morphotypes.

Universal deformations in inhomogeneous isotropic nonlinear elastic solids

Universal (controllable) deformations of an elastic solid are those deformations that can be maintained for all possible strain-energy density functions and suitable boundary tractions. Universal deformations have played a central role in nonlinear elasticity and anelasticity. However, their classification has been mostly established for homogeneous isotropic solids following the seminal works of Ericksen. In this article, we extend Ericksen’s analysis of universal deformations to inhomogeneous compressible and incompressible isotropic solids. We show that a necessary condition for the known universal deformations of homogeneous isotropic solids to be universal for inhomogeneous solids is that inhomogeneities respect the symmetries of the deformations. Symmetries of a deformation are encoded in the symmetries of its pulled-back metric (the right Cauchy–Green strain). We show that this necessary condition is sufficient as well for all the known families of universal deformations except for Family 5.

Free vibration and response of a variable speed rotating cantilever beam with tip mass

The study shows a new nonlinear model of a rotating cantilever beam with tip mass. The nonlinear model is built with considering axial geometric nonlinear and large curvature. On the basis of the nonlinear Green strain–displacement relations, the nonlinear motion equations are derived using the Hamilton principle. Applying the proposed dynamic model, the effect of various parameters on the natural frequency and stability is performed. The angular velocity value of frequency veer is obtained under different parameters. The dynamical response is calculated with variable rotating velocity. The comparison of numerical results shows good consistency with the other literature.

Comparison of Nutritional Composition in Red and Green Strains of Kappaphycus Alvarezii Cultivated in Gorontalo Province, Indonesia

Kappaphycus alvarezii is the most widely grown seaweed known by the commercial name “cottoni.” Several types or strains of K. alvarezii are grown in Indonesia, and each has a different appearance. There were red K. alvarezii, and green K. alvarezii collected from cultivation sites in Gorontalo Province, Sulawesi, Indonesia. The objective of this study was to compare the nutritional compositions of the red and green strain of K. alvarezii. The chemical composition analysis reveals that both strains contain ash, fat, crude fiber, protein, carbohydrate, vitamin C, and minerals; Ca (Calcium), Na (Sodium), and Fe (iron). While the red strain shows a higher ash content (4.62%), fat content (0.05%), protein (1.94%), carbohydrate (5.24%), vitamin C (3.42 mg.100 g−1), Na (467.65 mg.100 g−), and Fe (30.10 mg.100 g−), the green one has higher content of crude fiber (0.64%) and Na (9,307.17 mg.100 g−). Based on the result, the red K. alvarezii contains higher ash, fat, protein, carbohydrate, vitamin C, Ca, and Fe, while the green K. alvarezii is higher in water content, crude fiber, and Na. These two strains have no significant differences in nutrient composition and mineral content.

Strain-engineering enables reversible semiconductor–metal transition of skutterudite IrAs3

Green strain engineering makes the semiconductor-to-metal transition of skutterudite IrAs3 possible.

PRODUCTION OF CARRAGEENAN BY DIFFERENT STRAINS OF Kappaphycus alvarezii CULTIVATED IN SERANG, INDONESIA

Kappaphycus alvarezii is one of the main seaweeds cultivated in Indonesia. Its use as a raw material for the kappa-carrageenan industry has increased its cultivation activities. However, standard cultivation protocol for Kappaphycus alvarezii has yet to be well-documented, particularly on strain selection for kappa-carrageenan production. There are various strains of Kappaphycus alvarezii grown in Indonesia, specifically in Serang, Banten such as green, red, and yellowish green strains. In this study, growth rate, carrageenan yield, and gel strength from different strains of Kappaphycus alvarezii were investigated. It was observed that the specific growth rate of green type (4.14% /day) differed significantly from the other two types (red; 3.41% /day and yellowish green; 3.47% /day). The red type had the highest yield of carrageenan (45.16%) followed by yellowish green (36.66%) and green strain (33.67%). Gel strength was not significantly affected by the strain variations where the observed values for yellowish green, green, and red strain were 344.46, 316.91 and 313.10 g/cm2, respectively. Green Kappaphycus alvarezii had the highest biomass (0.27 g/cm/d) and carrageenan productivity (0.012 g/cm/d). It can be concluded that the green strain of Kappaphycus alvarezii is the most suitable for cultivation in Serang, particularly for the kappa-carrageenan industry. ABSTRAK: Kappaphycus alvarezii adalah sebahagian daripada rumpai air yang dituai di Indonesia. Penggunaannya sebagai bahan dasar kepada industri kappa-carrageenan telah menambah kepada aktiviti penuaian. Walau bagaimanapun, protokol penuaian biasa bagi Kappaphycus alvarezii adalah tertakluk pada dokumentasi penuh terutama dalam pemilihan strain pada penghasilan kappa-carrageenan. Terdapat pelbagai jenis strain Kappaphycus alvarezii yang tumbuh di Indonesia, terutama di Serang, Banten seperti hijau, merah, dan strain hijau kekuningan. Kajian ini, kadar pertumbuhan, hasil karaginan dan kekuatan gel daripada pelbagai strain Kappaphycus alvarezii telah dikaji. Didapati bahawa kadar pertumbuhan tertentu pada jenis hijau (4.14% /hari) berbeza ketara berbanding dari dua jenis lain (merah; 3.41% /hari dan hijau kekuningan; 3.47% /hari). Jenis merah mempunyai hasil karaginan tertinggi (45.16%) diikuti oleh hijau kekuningan (36.66%) dan strain hijau (33.67%). Kekuatan gel adalah tidak ketara mempengaruhi kepelbagaian variasi di mana nilai yang dipantau pada strain hijau kekuningan, hijau dan merah adalah 344.46, 316.91 dan 313.10 g/cm2, masing-masing. Kappaphycus alvarezii hijau mempunyai biojisim tertinggi (0.27 g/cm/d) dan penghasilan karaginan (0.012 g/cm/d). Kesimpulannya strain hijau Kappaphycus alvarezii adalah lebih sesuai untuk disemai di Serang terutamanya pada industri kappa-karaginan.

In Vivo Quantification of Regional Circumferential Green Strain in the Thoracic and Abdominal Aorta by Two-Dimensional Spiral Cine DENSE MRI

Regional tissue mechanics play a fundamental role in the patient-specific function and remodeling of the cardiovascular system. Nevertheless, regional in vivo assessments of aortic kinematics remain lacking due to the challenge of imaging the thin aortic wall. Herein, we present a novel application of displacement encoding with stimulated echoes (DENSE) magnetic resonance imaging (MRI) to quantify the regional displacement and circumferential Green strain of the thoracic and abdominal aorta. Two-dimensional (2D) spiral cine DENSE and steady-state free procession (SSFP) cine images were acquired at 3T at either the infrarenal abdominal aorta (IAA), descending thoracic aorta (DTA), or distal aortic arch (DAA) in a pilot study of six healthy volunteers (22–59 y.o., 4 females). DENSE data were processed with multiple custom noise reduction techniques including time-smoothing, displacement vector smoothing, sectorized spatial smoothing, and reference point averaging to calculate circumferential Green strain across 16 equispaced sectors around the aorta. Each volunteer was scanned twice to evaluate interstudy repeatability. Circumferential Green strain was heterogeneously distributed in all volunteers and locations. The mean spatial heterogeneity index (standard deviation of all sector values divided by the mean strain) was 0.37 in the IAA, 0.28 in the DTA, and 0.59 in the DAA. Mean (homogenized) peak strain by DENSE for each cross section was consistent with the homogenized linearized strain estimated from SSFP cine. The mean difference in peak strain across all sectors following repeat imaging was −0.1±2.3%, with a mean absolute difference of 1.7%. Aortic cine DENSE MRI is a viable noninvasive technique for quantifying heterogeneous regional aortic wall strain and has significant potential to improve patient-specific clinical assessments of numerous aortopathies, as well as to provide the lacking spatiotemporal data required to refine patient-specific computational models of aortic growth and remodeling.

Analysis of Soft-Elastohydrodynamic Lubrication Line Contacts on Finite Thickness

Soft elastohydrodynamic lubrication (soft-EHL) is an important mechanism in biotribological systems. The soft-EHL has some distinct differences from the traditional hard-EHL, and a systematic analysis factoring in key features of the “softness” appears to be lacking. In this paper, a complete soft-EHL line-contact model is developed. In the model, the half-space approximation is replaced by the finite thickness analysis; the geometrical and material nonlinearity due to finite deformation is factored in; the surface velocities altered by the curvature effect are considered, and the load balance equation is formulated based on the deformed configuration. Solutions are obtained using a finite element method (FEM). The film thickness, pressure distributions, and material deformation are analyzed and discussed under various entraining velocities, elastic modulus, and material thickness of the soft layer. Comparisons are made between soft-EHL and hard-EHL modeling assumptions. The analyses show that the classical EHL modeling is not suitable for soft materials with high loads. The results show that the finite deformation (Green strain) should be considered in soft-EHL analysis. In the contact region, the hard EHL solver overestimates the pressure distribution and underestimates the film thickness and deformation.

The impact of temperature and photosynthetically active radiation on the growth and pigments concentration in Baltic picocyanobacterium Synechococcus sp.

The experiments on three Baltic picocyanobacterial strains of Synechococcus (BA-120 – red strain, BA-124 – green strain and BA-132 – brown strain) were conducted at four scalar irradiances in Photosynthetically Active Radiation (PAR) and four temperature levels. The main aim of this work was to estimate the effect of environmental conditions (temperature and PAR) on cell concentration and photosynthetic pigments (Chlorophyll a – Chl a and Carotenoids – Car) contents. The ranges of PAR and temperatures were 10, 100, 190, 280 μmol m-2 s-1 and 10, 15, 20, 25ºC, respectively. The experiment was carried in a medium of salinity of 8. The number of Synechococcus sp. cells was determined using a BD Accuri™ C6 flow cytometer. The pigments contents were determined by a spectrophotometric method. In this work, it was found that elevated intensity and temperature have, on average, a positive effect on cell concentration for Synechococcus sp. The highest cells concentrations were noted at the highest PAR (280 µmol m-2 s-1) and the highest T (25ºC) for green and brown strains (BA-124 and BA-132, respectively) and at 190 µmol m-2 s-1 and 25ºC for red strain (BA-120). Comparing the strains at each PAR level and temperature, the highest cell concentration was noted in green strain (36·106 cell ml-1), while the lowest was observed in red strain (8·106 cell ml-1). In general, in the two strains of Synechococcus (BA-120 and BA-132), the highest Car and Chl a contents were observed at the lowest light intensity and the highest temperature. On the other hand, Car and Chl a maximum content in BA-124 were noted at the lowest light and temperature. The experiments on Synechococcus strains demonstrated their high capacity to acclimate to a wide range of PAR and temperature levels. The three strains of Synechococcus showed adaptation capabilities, since they were able to change the composition of their photosynthetic pigments to use light quantity better and to protect the cells from the unfavourable effect of elevated light and temperature.

A model for magneto-elastic behaviour

In this paper, a coupled magnetoelastic model for isotropic ferromagnetic materialsis presented. The constitutive equations are written on the basis of the total energy in whichthe right Cauchy-Green strain tensor and the Lagrangian form of the magnetic eld strengthare used as the basic state variables. It is also applied to ferromacnetic electric steel for whichthe material parameters are calibrated.