Effect Of Varying Size Research Articles

Vertically etched silicon nano-rods as a sensitive electron detector

We have used vertically etched silicon nano-rods to realize electron detectors suitable for scanning electron microscopes. The results of deep etching of silicon nano-structures are presented to achieve highly ordered arrays of nano-rods. The response of the electron detector to energy of the primary electron beam and the effects of various sizes and materials has been investigated, indicating its high sensitivity to secondary and back-scattered electrons. The miniaturized structure of this electron detector allows it to be placed in the vicinity of the specimen to improve the resolution and contrast. This detector collects electrons and converts the electron current to voltage directly by means of n-doped silicon nano-rods on a p-type silicon substrate. Silicon nano-rods enhance the surface-to-volume ratio of the detector as well as improving the yield of electron detection. The use of nano-structures and silicon nanowires as an electron detector has led to higher sensitivities than with micro-structures.

Effect of Various Citrus Sizes on the Resistance to Gas Diffusion

This study investigated the effect of various sizes of citrus on their resistance (R) to gas diffusion. The purpose of the investigation was to compare the value of R in 3 different sizes of citrus. To measure the R to gas diffusion in citrus, the study applied ethane efflux method. This is the method which the evolution phenomenon of ethane was measured by applying Fick's Law. The results showed that R of ethane (C2H6) gas was dependent on citrus size. It can be seen that the larger the size of the fruit, the greater the R value, i.e. M size had R=4.33x105s.m-1, L size had R=4.99 x105s.m-1 and 3L size had R=6.84 x105s.m-1.This finding indicated that the fruit sizes can be considered as an important factor in designing storage control atmosphere (CA) condition for citrus.

The effect of gold nanoparticle size on osteogenic differentiation of adipose-derived stem cells

There have been many medical applications based on gold nanoparticles (GNPs) over the past several centuries. Recently, researchers have focused on bone tissue engineering applications utilizing GNPs. The effect of various sizes of gold nanoparticles on the differentiation of human adipose-derived stem cells (ADSCs) into osteoblasts was investigated. The concentration of gold nanoparticles was fixed at 1μM and varying sizes of 15, 30, 50, 75 and 100nm (spherical GNPs) were used. The lack of cytotoxicity was confirmed by establishing viability of ADSCs using cell counting kit-8 (CCK-8) and live/dead assays. The results showed that each size of GNPs had no significant toxicity on ADSCs during 1week of incubation. Osteogenic differentiation of ADSCs was confirmed by alkaline phosphatase (ALP) staining, ALP activity, calcium deposition, and real time PCR experiments. It was found, through dark field assays and microscope cell images, that 30nm and 50nm GNPs were preferentially up taken into the ADSCs. As expected, all sizes of gold nanoparticles promoted the differentiation of ADSCs toward osteoblasts more than control. Among all sizes, 30 and 50nm GNPs appeared to have the highest differentiation rates. The data consistently demonstrated that 30 and 50nm GNPs are the most effective in promoting osteogenic differentiation of ADSCs.

PERTUMBUHAN SEMAI CENDANA (Santalum album Linn.) PADA BEBERAPA UKURAN KANTUNG PLASTIK DI DAERAH SEMIARID

Mortality of sandalwood plantings in the semiarid region is high (less than 50 %), due to poor quality. One of seedling of the alternatives to reduce this mortality is using optimal container size. The method is hoped to increase the growth and survival rate of sandalwood seedlings in the field. The objective of this study was to determine the effects of various sizes of seedling container on growth and to recommend the best polybag size for sandalwood nursery. The study was conducted in Complete Randomized Design method using container size of polybag (wide x length as main treatment) i.e.: 7 x 20 cm2, 8 x 20 cm2, 9 x 20 cm, 10 x 21 cm2, 11 x 22 cm2, 12 x 23 cm2, 13 x 23 cm2, 14 x 24 cm2, and 15 x 252 cm. Experiment consisted of 30 replications. The polybag was filled with the potting medium consisting soil, sand, and compost in volume ratio of 4:1:1 and sown with Alternanthera sp. as a primary host plant in all treatment. The results of the experiment proved that application of polybag size (7 cm x20 cm to 15 cm x 25 cm) had significant effects on height, diameter, dry weight total, top root ratio, quality index and survival of sandalwood seedling at six months old. The application of polybag size 15 x 25 cm2 (1080 mL) produced the best growth i.e. height (24.53 cm ), diameter (4.27 mm), dry weight total (1.86 g), top root ratio (0.54), quality index (0.28) and survival (92 %). Keywords: seedling growth, polybag size, Sandalwood

Development of laser dye-doped silica nanoparticles embedded optical preform for bio-analysis

I present here the study of optical and fluorescence properties, structure and morphology of silica nanoparticles bearing laser dye molecules are electrostatically attached with high refractive index organic dopant in acrylic optical preform rod. The photo physical fluorescence behaviour of laser dye molecules at the surface of different size and shape of silica nanoparticles has been reported. The interaction of laser dye-nanoparticles, nature of particles, and effect of various sizes and shapes of silica nanoparticles on fluorescence properties has been investigated. The developed optical preform has high potential for possible applications as bio-analysis sensor probe.

Vortex generation and flow pattern development after a solitary wave passing over a bottom cavity

Several vortices are generated immediately inside the cavity for a short duration when a solitary wave passes over a bottom cavity in shallow water. Afterward, the primary vortex grows gradually in size and then is transported outward to breed another counter-rotating vortex to form a jet in the tranquil environment. In this study, a two-dimensional streamfunction–vorticity model was treated in a transient grid to conform the free surface and formulated by the Finite Analytic (FA) discretization to seek a time-accurate numerical solution. We used an overset grid to refine the small region around the cavity to improve the solution accuracy and obtain computational efficiency in the analysis. The model was first validated for a quasi-steady boundary-layer flow, induced by a solitary wave passing over a flat bottom, through the comparison of velocity profiles with Liu et al. [J Fluid Mech 2007;574:449–63]. Then, the evolved vortical flow for the cavity problem was investigated under the effects of various sizes of a cavity and various amplitudes of the incident solitary wave. These simulated results showed consistent agreement in the evolved vortex patterns with the visualization experiment in laboratory.

ELISA measurement of specific non-antigen-bound antibodies to Aβ1-42 monomer and soluble oligomers in sera from Alzheimer's disease, mild cognitively impaired, and noncognitively impaired subjects

BackgroundThe literature contains conflicting results regarding the status of serum anti-Aβ antibody concentrations in Alzheimer's disease (AD). Reduced levels of these antibodies have been suggested to contribute to the development of this disorder. The conflicting results may be due to polyvalent antibodies, antibody "masking" due to Aβ binding, methodological differences, and/or small sample sizes. The objectives of this pilot study were to compare serum anti-Aβ antibody concentrations between AD, mild cognitive impairment (MCI), and elderly noncognitively impaired (NCI) subjects while addressing these issues, and to perform power analyses to determine appropriate group sizes for future studies employing this approach.MethodsSerum antibodies to Aβ1-42 monomer and soluble oligomers in AD, MCI, and NCI subjects (10/group) were measured by ELISA, subtracting polyvalent antibody binding and dissociating antibody-antigen complexes. Differences in mean antibody levels were assessed for significance with repeated measures ANOVA using restricted maximum likelihood estimation, using Tukey-Kramer tests and confidence intervals for multiple comparisons. Spearman's rank correlation was used to determine associations between anti-monomer and anti-oligomer antibody concentrations. Estimated sample sizes required to detect effects of various sizes were calculated.ResultsThere were no significant differences between groups for mean anti-Aβ antibody levels, although these tended to be higher in AD than NCI specimens. Estimated group sizes of 328 and 150 for anti-Aβ monomer and oligomer antibodies, respectively, would have been required for 80% power for significance at 0.05 for a 25% increase in the AD mean relative to the NCI mean. Serum antibody concentrations to Aβ monomer and oligomers were strongly associated (correlations: 0.798 for undissociated sera, 0.564 for dissociated sera). Antibody-antigen dissociation significantly increased anti-Aβ monomer but not anti-Aβ oligomer antibody levels.ConclusionsThe findings in this pilot study are consistent with relatively similar concentrations of specific, non-antigen-bound antibodies to Aβ1-42 monomer and soluble oligomers in AD, MCI, and NCI sera. The differences between groups for these antibodies would have required approximate group sizes of 328 and 150, respectively, for a high probability for statistical significance. These findings do not support the hypothesis that reduced levels of anti-Aβ antibodies might contribute to AD's pathogenesis.

Reduction of local scour at a bridge pier fitted with a collar in a 180 degree flume bend (Case study: oblong pier)

Local scouring around the bridges pier occurs because of flow separation and developing several vortexes around the bridge pier. Such scour hole can cause failure of the bridge especially during the river floods. In this study, the use of oblong collars for reducing the effects of local scour at a bridge pier is presented together with the time aspect of the scour development. The study was conducted using in a 180 degree laboratory flume bend. Tests were conducted using one oblong pier in positions of 60degree under one flow conditions. In this study, the time development of the local scour around the oblong pier fitted with and without collar plates was studied. The effects of various sizes of collars fitted on the temporal development of scour depth at the oblong pier were also studied. The time development of the scour hole around the model pier with and without a collar installed was compared with similar studies on bridge piers. The results of the model study indicated that the maximum depth of scour is highly dependent on the experimental duration. It was observed that, as the size of a collar plate increases, the scour decreases. So minimum depth of scour is dependent on the 3D collar.

Numerical Investigation of Heat Transfer Enhancement in a Microchannel With Grooved Surfaces

This paper presents a numerical investigation for two types of grooves (rectangular and arc shapes) fabricated in the microchannel surfaces, which leads to enhancement in single-phase cooling. The pressure drop and heat transfer characteristics of the single-phase microchannel heat sink were investigated numerically for laminar flow. For this purpose, the conjugate heat transfer problem involving simultaneous determination of temperature fields in both solid and liquid regions was solved numerically. The numerical model was validated with comparison to experimental data, in which good agreement was seen. A simple microchannel with available experimental data was selected, and it was shown that using grooved surfaces on this microchannel has a noticeable effect and heat removal rate can be increased using this technique. The results depict that the arc grooves have a higher heat removal flux compared with rectangular grooves but the latter have a higher coefficient of performance for the case in which grooves are made in the floor and both side walls. Also, it was shown that a grooved microchannel with higher wall thickness and lower mass flow rate of cooling water has a higher heat removal flux and coefficient of performance compared with a simple microchannel with minimum wall thickness. Effect of various sizes and distances of the floor grooves was determined, and the cases for maximum heat removal rate and coefficient of performance for both rectangular and arc grooves were obtained.

A study of the effect of thumb sizes on mobile phone texting satisfaction

This paper investigates the effect of participants' varying thumb sizes in relation to the experience of using mobile phone keypads for sending text messages. The keypad design factors considered in the study were key size, shape, texture, space between keys, layout, and simplicity. One hundred and ten people participated in the study. Their age ranged between 17 to 25 years old. The researchers recorded the participants' thumb lengths and circumferences. Participants' positive or negative satisfaction with using mobile phone keypads correlates to their thumb length and circumference. For example, if a participant's thumb circumference was large, he or she tended to be dissatisfied with the key size and space between keys. Results confirm that varying thumb sizes affect users' text messaging satisfaction. Mobile phone manufacturers and designers can use the findings in this study to design customized mobile phones that cater to users with large thumbs. This may increase their customer's text messaging satisfaction.

Size effect in reactivity of copper nanoparticles to carbon tetrachloride degradation

Surface area-normalized rate constants ( k SA) of reaction between metallic nanoparticles and reducible contaminants, such as chlorinated hydrocarbons, heavy metals, and nitrate, have been reported to be dramatically increased as compared to that of commercial metallic powder. However, k SA for individual pollutants in previously published data vary by as much as 1–2 orders of magnitude and much of this variability is due to the effect of various sizes. The size dependence of the reactivity of nanoparticles is not yet fully understood; however, yielding nanoparticles with uniform size and without agglomeration during the period of reaction would demonstrate the effect of varying particle size. In this study, resin-supported zerovalent copper with average particle size of 7, 10, 18, 26, and 29, respectively, were successfully synthesized and evidenced no agglomeration during the reaction period of 10 h. The k SA of copper nanoparticles ( k n,SA) was 110–120 times higher than that of powdered copper particles ( k p,SA) when the copper particle size was about 10 nm. However, for diameters of 18–29 nm, the ratio of k n,SA/ k p,SA was around 10–20, indicating that the reactivity of small copper nanoparticles (∼10 nm) varies discontinuously. Thus, most variability in previous k SA is attributed to the presence of small nanoparticles.

Contextual modulation involves suppression and facilitation from the center and the surround

In psychophysics, cross-orientation suppression (XOS) and cross-orientation facilitation (XOF) have been measured by investigating mask configuration on the detection threshold of a centrally placed patch of sine-wave grating. Much of the evidence for XOS and XOF comes from studies using low and high spatial frequencies, respectively, where the interactions are thought to arise from within (XOS) and outside (XOF) the footprint of the classical receptive field. We address the relation between these processes here by measuring the effects of various sizes of superimposed and annular cross-oriented masks on detection thresholds at two spatial scales (1 and 7 c/deg) and on contrast increment thresholds at 7 c/deg. A functional model of our results indicates the following (1) XOS and XOF both occur for superimposed and annular masks. (2) XOS declines with spatial frequency but XOF does not. (3) The spatial extent of the interactions does not scale with spatial frequency, meaning that surround-effects are seen primarily at high spatial frequencies. (4) There are two distinct processes involved in XOS: direct divisive suppression and modulation of self-suppression. (5) Whether XOS or XOF wins out depends upon their relative weights and mask contrast. These results prompt enquiry into the effect of spatial frequency at the single-cell level and place new constraints on image-processing models of early visual processing.

Effect of Immune Complex on the Biomechanics of Blood Flow in Common Glomerulonephritis Diseases

Glomerulonephritis (GN) is a common nephrological disorder. The correlation between degree of glomerular damage, severity of GN, and development of hypertension is an interesting topic in present research on GN. Although the progression of GN is proved to associate with hypertension, no clear pathogenesis is reported. In this study, the author assesses the effect of various sizes of immune complex in three common GN diseases on the biomechanics of blood flow in the renal vascular. Further discussion on the impact on hypertension is also provided.

Effects of titanium particle size on osteoblast functions in vitro and in vivo.

The formation of titanium (Ti)-wear particles during the lifetime of an implant is believed to be a major component of loosening due to debris-induced changes in bone cell function. Radiographic evidence indicates a loss of fixation at the implant-bone interface, and we believe that the accumulation of Ti particles may act on the bone-remodeling process and impact both long- and short-term implant-fixation strengths. To determine the effects of various sizes of the Ti particles on osteoblast function in vivo, we measured the loss of integration strength around Ti-pin implants inserted into a rat tibia in conjunction with Ti particles from one of four size-groups. Implant integration is mediated primarily by osteoblast adhesion/focal contact pattern, viability, proliferation and differentiation, and osteoclast recruitment at the implant site in vivo. This study demonstrates the significant attenuation of osteoblast function concurrent with increased expression of receptor activator of nuclear factor kappaB ligand (RANKL), a dominant signal for osteoclast recruitment, which is regulated differentially, depending on the size of the Ti particle. Zymography studies have also demonstrated increased activities of matrix metalloproteinases (MMP) 2 and 9 in cells exposed to larger Ti particles. In summary, all particles have adverse effects on osteoblast function, resulting in decreased bone formation and integration, but different mechanisms are elicited by particles of different sizes.

Effect of Various Sizes of Mesh on Dewatering Behavior of Effluent Slurry

Click to increase image sizeClick to decrease image sizeKeywords: Effluent Slurry Small Size Biogas Plant Mesh Size Drying Characteristics Filtered Water

The Tolman Surface Brightness Test for the Reality of the Expansion. II. The Effect of the Point-Spread Function and Galaxy Ellipticity on the Derived Photometric Parameters

To complete the Tolman surface brightness test on the reality of the expansion of the universe, we need to measure accurately the surface brightness profiles of the high-redshift galaxy sample. To quantify this accuracy, we investigate the effects of various sizes of point-spread functions composed of telescope diffraction, CCD pixel resolutions, and ground-based seeing on the measurements of mean surface brightness for galaxies whose effective (half-light) radii range from 070 to 017. We have done the calculations using two synthetic galaxies of effective radii of 070 and 025 with point-spread functions of 01, 03, and 09, full width at half maximum. We have also compared actual observations of three high-redshift galaxies in the cluster Cl 1324+3011 (z = 0.76) made both with the ground-based Keck 10 m telescopes in seeing of about 09 and with the Hubble Space Telescope (HST) with a point-spread function that is approximately 10 times smaller. The conclusion is that HST data can be used as far into the galaxy image as a Petrosian metric radius of η = 1.3 mag, whereas the ground-based data will have systematic errors of up to 2.9 mag in the mean surface brightness at η values of less than 2.2 mag for all but the largest galaxies at redshifts of z ≈ 0.7. In the final section, we compare the differences in derived average surface brightness for nearly circular galaxy images with highly flattened images. The comparison is made by using the two reduction procedures of (1) integrating the profile curves using circular apertures, and (2) approximating an "equivalent circular" galaxy that is highly elongated by using an "effective" radius of (ab)1/2, where a and b are the semimajor and semiminor axis, respectively, of the best-fitting ellipse. The conclusion is that the two methods of reduction give nearly identical results and that either method can be used to analyze the low- and high-redshift galaxy samples used in the Tolman test.

Compressive buckling of laminates with an embedded delamination

In this paper, a buckling analysis of laminates with an embedded delamination has been conducted by employing a finite-element method based on the Mindlin plate theory. An effective solution method has been put forward to deal with the contact problem in the buckling mode. In this method, an iterative updating process incorporating first-order sensitivity analysis and quadratic programming technique has been proposed for computing fictitious forces in the contact area, which can be used to calculate stiffness parameters of some artificial springs. Finally, the penetration between two delaminated layers in the buckling mode can be effectively prevented by inserting these artificial springs into the overlapped area in the buckling mode. Numerical examples indicated that this method is very efficient for solving the contact problem in buckling analysis. Its accuracy and convergence speed are very high. The numerical results demonstrate that the contact analysis is very important for buckling analysis in some cases. The effects of various sizes, shapes and positions of the delamination and the fiber angle of the sublaminate on the buckling load have also been investigated.

Boundary element alternating method applied to analyze the stress concentration problems of multiple elliptical holes in an infinite domain

This paper presents an efficient boundary element alternating method for analyzing the interactions among multiple elliptical holes in a two dimensional infinite domain under remote uniform stresses. Instead of the analytical solution used in the conventional alternating method, the stress distribution in an infinite domain with a single elliptical hole subjected to the arbitrary tractions across the boundary is solved by the boundary element method. Then this solution correlates with a successive iterative superposition process capable of satisfying the prescribed boundary for each elliptical holes of the problem. Both the effects of various sizes of holes and ligaments among ellipses on the stress concentration are studied in detail. In addition, the computed results and the available referenced solutions closely corresponds to each other indicate the method’s accuracy and efficiency.

Experimental and Analytical Study of the Frequencies of an S-C-S-C Plate Carrying a Concentrated Mass

The present work is concerned with the determination of the fundamental frequencies of a simply supported-clamped-simply supported-clamped (SCSC) plate carrying a concentrated mass. An energy method based on the Rayleigh’s approach has been developed to obtain approximate closed-form solutions. A finite element analysis is also presented for comparison. Extensive experimental investigation through a shaker system was conducted to collect useful test data. The comparison of experimental results with theoretical predictions of the energy method shows favorable correlations. In the parametric study, the effect of various sizes of the concentrated mass, and the effect of the variation in the plate geometry and material properties on the fundamental frequencies of the plate are presented.

Ultimate Strength of leg of Jack-up Rig

Jack-up type oil rigs are composed of legs and platforms. The degree of redundancies of legs are generally fewer than those of platforms. As a structure becomes less redundant, reserved strength after the initial yielding tends to decrease. So, it is important to clarify the ultimate strengths of tubular joints which are leading causes of overall failures of the legs.In the 1st report, the authors carried out theoretical and experimental investigations into the rigidity and local strength of T-joint of circular tube under a concentrated normal load transmitted from the brace. The T-joint model used in the study is composed of a chord reinforced with a built-in center-rib and a brace, and is supported by a leg guide.In the present paper, they studied the rigidity and local strength of the same T-joint model under both a concentrated normal load and bending moment transmitted from the brace. They performed series of theoretical analyses and experiments on the models.Main conclusions obtained in this study are shown as follows.1) The rigidity of the T-joint can be evaluated by formulae developed in consideration of the effects of various sizes of the chord and brace.2) The ultimate strength interaction curves of the T-joint are presented.3) The failure modes of the T-joint are clarified.