Response surfaces

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PERFORMANCE OF FUZZY INFERENCE SYSTEMS TO PREDICT THE SURFACE TEMPERATURE OF BROILER CHICKENS Marcelo Bahuti

PERFORMANCE OF FUZZY INFERENCE SYSTEMS TO PREDICT THE SURFACE TEMPERATURE OF BROILER CHICKENS Marcelo Bahuti

The fuzzy systems (triangular functions with wtaver and wtsum defuzzification and Gaussian functions with wtaver defuzzification) represented by the response surfaces (Figures 7a, b, and c) yielded the same statistical indices when compared with the experimental data (Table 1). However, Student’s t-test for equality of means (α = 5%) was applied to compare the other t s values not evaluated

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Microencapsulation of turMeric oleoresin in binary and ternary blends of guM arabic, Maltodextrin and Modified starch

Microencapsulation of turMeric oleoresin in binary and ternary blends of guM arabic, Maltodextrin and Modified starch

In this study it was possible to encapsulate turmeric oleoresin by the spray drying method using binary and ternary mixtures of gum Arabic, maltodextrin and modified corn starch as wall materials. The simplex centroid experimental design was a valuable tool for evaluating the main effects of the proportions of gum Arabic, maltodextrin and modified corn starch on the responses: encapsulation efficiency, curcumin retention, process yield and water content. The response surfaces showed that mixtures containing higher proportions of modified starch and gum Arabic resulted in higher encapsulation efficiency and curcumin retention, whereas the process yield and water content increased with higher proportions of maltodextrin and gum Arabic, respectively. All the studied wall matrices resulted in microcapsule solubility higher than 85 %. The capsules obtained showed typical morphology of spray dried particles, with some differences in size being observed depending on the wall material formulation.
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EFFECT OF FLUIDIZED-BED PROCESS VARIABLES ON CONTROLLED-RELEASE OF NITROGEN AND COATING

EFFECT OF FLUIDIZED-BED PROCESS VARIABLES ON CONTROLLED-RELEASE OF NITROGEN AND COATING

The FESEM micrograph of a St-PCU cross section is given in Fig. 7. Forty thickness points have been chosen for one granule to report coating uniformity. To study the effect of process parameters on coating uniformity in detail, the response surfaces are presented herewith. From Fig. 8a, it is observed that at the highest fluidizing gas temperature and lowest atomizing pressure, the CV of coating thickness is highest, indicating the lowest uniformity. This is because of premature drying and poor spreading of spray droplets at a high gas temperature and rough & porous coating that results at low atomizing pressure because of the generation of bigger droplets. At the highest atomizing pressure and lowest gas temperature, the CV of coating thickness is moderately high. The higher atomizing pressure not only produces very small spray droplets (Paulo Filho et al., 2006) but also helps for the impingement and spreading of spray droplets due to its momentum, which consequently increases the surface area and hence facilitates the solvent evaporation (Tobiska and Kleinebudde, 2003). However, this advantage can only be achieved if there is sufficient gas temperature for the solvent to evaporate from these tiny droplets. A low gas temperature not only causes delayed evaporation of the droplets, but also facilitates the formation of temporary aggregates of the granules, which results in a rough and porous coating after they detach from each other once the liquid bridge between them is broken due to solvent evaporation. As a result of this phenomenon, the coating uniformity is disturbed. At the lowest gas temperature and lowest atomizing pressure, the CV of thickness is relatively high, but lower than the previous two cases. Similarly, at the maximum values of both of these process variables, the CV is high but definitely lower than the first two cases. So it can be concluded that the extreme conditions of gas temperature and atomizing pressure have a negative effect on coating uniformity.
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Effect of temperature and leaf wetness duration on infection of sweet oranges by Asiatic citrus canker

Effect of temperature and leaf wetness duration on infection of sweet oranges by Asiatic citrus canker

The monomolecular-beta generalized function allowed construction of response surfaces for disease severity (Fig. 3), mean lesion density (Fig. 4) and mean lesion size (Fig. 5) for each cultivar. The coefficients of determination and the parameters estimated in each fit are shown in Table 3. The minimum and maximum temperatures estimated by the monomolecular-beta equation were 12 and 40 ° C, respectively (Table 3). In general, as the tem- perature increased, disease severity, density of lesions and lesion size increased, up to approximately 35 ° C, after which they decreased (Figs 3 –5). The maximum esti- mated severity at 24 h wetness duration occurred between
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J. Braz. Chem. Soc.  vol.20 número1

J. Braz. Chem. Soc. vol.20 número1

work, the obtained increase was 1.7 times, almost without recovery losses. This was due to the use of an experimental design and analysis of the response surfaces, which allowed for the process optimization to maximize the responses. A simple and efficient purification procedure can significantly reduce the overall costs and can affect process viability. The optimization step is very important to reach the best results for purity, without significant losses in recovery, since C-phycocyanin is a product with a high aggregated value. 38

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J. Braz. Chem. Soc.  vol.26 número1

J. Braz. Chem. Soc. vol.26 número1

Mathematical functions that generate response surfaces can be fitted to experimental data using the classical least square methodology or alternative methodologies, such as artificial neural networks (ANN). ANN provide an attractive possibility for providing non-linear modeling for response surfaces. In classical response surface methodology (RSM), the number of terms in the polynomial equation is limited to the number of experimental design points. On the other hand, ANN methodology allows the modeling of complex relationships without this limitation. Its analysis is quite flexible in regard to the number and form of the experimental data having better predictive power than regression models. Regression analyses are dependent on predetermined statistical significance levels, and less significant terms are usually not included in the model. With the ANN method, all data are used making the models more accurate. 12,15
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Evaluating sources of uncertainty in modelling the impact of probabilistic climate change on sub-arctic palsa mires

Evaluating sources of uncertainty in modelling the impact of probabilistic climate change on sub-arctic palsa mires

Impact response surfaces can also be used, in combina- tion with probabilistic projections of climate change, to es- timate risks of future impacts. The risk of reduced North- ern Fennoscandian area suitable for palsas to less than half the baseline area was quantified as very likely (>90 % prob- ability; 90 % confidence) for periods from 2030–2049 on- wards, with total loss of suitability judged as likely (>66 % probability; 90 % confidence) by 2080–2099 under the A1B emission scenario and using an ensemble of 75 GAM palsa models (confidence based on 5 to 95 percentiles of combined box plots in Fig. 7). The risk of total loss of palsa area from Northern Fennoscandia was reduced for a mitigation scenario under which global warming was constrained to be- low 2 ◦ C relative to pre-industrial climate, although it, too,
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Microbial biogeography of public restroom surfaces.

Microbial biogeography of public restroom surfaces.

To determine the potential sources of bacteria on restroom surfaces and how the importance of different sources varied across the sampled locations, we used the newly developed Source- Tracker software package [25]. The SourceTracker model assumes that each surface community is merely a mixture of communities deposited from other known or unknown source environments and, using a Bayesian approach, the model provides an estimate of the proportion of the surface community originating from each of the different sources. When a community contains a mixture of taxa that do not match any of the source environments, that portion of the community is assigned to an ‘‘unknown’’ source. Potential sources we examined included human skin (n = 194), mouth (n = 46), gut (feces) (n = 45) [26] and urine (n = 50), as well as soil (n = 88) [27] and faucet water (n = 5, see above). For skin communities, sequences collected from eight body habitats (palm, index finger, forearm, forehead, nose, hair, labia minora, glans penis) from seven to nine healthy adults on four occasions were used to determine the average community composition of human skin [26]. The mouth (tongue and cheek swabs), gut and urine communities were determined from the same individuals although the urine-associated communities were not published in the initial report of these data [26]. While urine is generally considered to be sterile, it does pick up bacteria associated with the urethra and genitals [28,29]. The average soil community was determined from a broad diversity of soil types collected across North and South America [27].
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New examples of surfaces in H

New examples of surfaces in H

rest of the paper is divided into three sections. The first one describes the definitions of the normal Gauss map in context of this paper and the second conformal structure on surfaces and states Theorem 1. The second section gets two local examples within the Euclidean ruled surface and in the last section some global properties of the ruled surfaces and translational surfaces are proven.

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Bacterial Adherence to Different Inert Surfaces Evaluated by Epifluorescence Microscopy and Plate Count Method

Bacterial Adherence to Different Inert Surfaces Evaluated by Epifluorescence Microscopy and Plate Count Method

The adherence of Listeria inoccua L6a and Staphylococcus aureus ATCC6538 was evaluated on stainless steel (SS), polycarbonate (PC) and polypropylene (PP) chips. The EP results showed a significant difference (p<0.05) among the microorganism species interactions, the surfaces and the contact time. The number of adhered cells on the chip surfaces increased as contact time increased and the number of L. innocua or S. aureus on the surface of SS, PC and PP chips reached 1.0x10 5 CFU/cm 2 after 12 h of contact, in both methods. The CP method showed a better sensitivity to detect low number of adhered cells. The EP was better when the average number of adhered cells was between 10 and 100 per microscopy field.
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J. Microw. Optoelectron. Electromagn. Appl.  vol.13 número2

J. Microw. Optoelectron. Electromagn. Appl. vol.13 número2

Abstract — Self-affine property of a modified multifractal Cantor geometry is exploited to design frequency selective surfaces (FSS) with multiband response. The main advantage of the proposed structure is to design multiband FSS with multiple frequency ratios between the adjacent bands and easily-built structures. In addition, the proposed structure increases the degree of freedom in design of multiband FSS response according to the number of fractal iterations. The validation of the proposed structure was initially verified through simulations in Ansoft Designer 3.5 and then a prototype was built with a validation purpose.
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The Design of Simple Bacterial Microarrays: Development towards Immobilizing Single Living Bacteria on Predefined Micro-Sized Spots on Patterned Surfaces.

The Design of Simple Bacterial Microarrays: Development towards Immobilizing Single Living Bacteria on Predefined Micro-Sized Spots on Patterned Surfaces.

Fig 2. Images of glass surfaces and glass surfaces precoated with chemicals reducing bacterial adhesion, patterned with chemicals promoting bacterial adhesion, immersed in a solution containing bacteria and finally rinsed and covered with LB. Results obtained for the three chemicals potentially reducing bacterial adhesion (BSA, PVA or PEG) are shown. The substrates are patterned with one of three chemicals promoting bacterial adhesion (PLL, PEI or PD) using μCP with a PDMS stamp with 5 μm lines (Fig 1d) and immersed in a solution containing bacteria. All scalebars are 10 μm. The combination of chemicals investigated in each experiment is indicated on the figure. The surfaces were rinsed in MilliQ water after the incubation with bacteria (P. putida KT2440) in order to remove weakly adhering bacteria. During imaging the surfaces were covered with LB in order to minimize stress induced in the attached bacteria. The images are obtained by using transmission light microscopy, and were captured on a Leica TCS SP5 with a
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Surface coverage in wireless sensor networks based on delaunay tetrahedralization

Surface coverage in wireless sensor networks based on delaunay tetrahedralization

The proposed approach was tested on three distinct reliefs: plain, plateau and hilly. These reliefs are commonly found on applications of WSN for forest fire control, for instance. The length of the example surfaces were fixed in 2000 x 2000 m². In figure 1(a) is shown the plain relief, with total area of 4022.23 m². In figure 1(b) is presented the plateau relief, with total area of 4080.24 m² and in figure 1(c) is presented the hilly relief (4405.92 m²). The values were obtained considering peaks and valleys.

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Evaluation of the interactions between human cells and silicone rubber surfaces modified by Atom Transfer Radical Polymerization

Evaluation of the interactions between human cells and silicone rubber surfaces modified by Atom Transfer Radical Polymerization

prostheses in 1960, and from then on has been one of the materials of choice to be used in implants. (3; 12; 15) PDMS is a linear silicone that is in the fluid state at room temperature and is soluble in organic solvents. Its physical properties depend widely from its molar mass. A low molar mass it’s in the origin of materials with low viscosity, and high molar mass materials have a viscoelastic behavior and are gum-like. (12) PDMS has a low surface tension (20.4 mN/m) and can wet most surfaces. Because of its methyl groups that point to the outside, PDMS gives rise to very hydrophobic films and presents a surface with good releasing properties. This material is widely used in many applications due to the characteristics mentioned above and due to its lack of toxicity. (1)
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A proof of a general isoperimetric inequality for surfaces

A proof of a general isoperimetric inequality for surfaces

We could free our proof from the dependence on the classical case of constant curvature by using a symmetrization process (since we already have the inequality). H[r]

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Capacidade de adesão, formação de biofilme e resistência a sanitizantes de cepas de staphylococcus aureus isoladas de serviços de alimentação

Capacidade de adesão, formação de biofilme e resistência a sanitizantes de cepas de staphylococcus aureus isoladas de serviços de alimentação

This study aimed to assess the capacity of adhesion, the kinetic of separation and biofim formation of strains of Staphylococcus aureus isolated from food services surfaces cultivated in a vegetable broth at 7 and 28°C, and the efficacy of peracetic acid (30 mg/L) and sodium hypochlorite (250 mg/L) in removing the bacterial cells in the biofilm. The strains adhered over 4 log cfu/cm 2 to stainless and polypropylene surfaces regardless the kind of surface and temperature of incubation. Cell detachment was about 10 3 cfu/cm 2 in the first 6 contacts with agar characterizing a high persistence of cells on the tested surfaces. Number of cells (10 5 – 10 7 cfu/cm 2 ) needed for biofilm formation was noted at all experimental systems already after 3 days. A range of 2.0 to 3.3 and 1.5 to 2.1 log cfu/cm 2 was observed in the reduction of cells in biofilm matrix caused by peracetic acid and sodium hypochlorite, respectively. From these results, the strains assayed revealed high capability to adhere and form biofilm on food contact surfaces.
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Borehole Seismic and Strain Observatories in Seafloor Settings &ndash; Experiences after ODP Legs 186, 191, 195 and Future Plans

Borehole Seismic and Strain Observatories in Seafloor Settings &ndash; Experiences after ODP Legs 186, 191, 195 and Future Plans

especially in the horizontal component. This prevents precise in the horizontal component. This prevents precise the horizontal component. This prevents precise the horizontal component. This prevents precise horizontal component. This prevents precise analysis of the hypocenter and mechanism of earthquakes. Borehole records do not show such a response for all compo- s do not show such a response for all compo- do not show such a response for all compo- a response for all compo- response for all compo- nents; therefore, installing seismometers in boreholes will ; therefore, installing seismometers in boreholes will therefore, installing seismometers in boreholes will therefore, installing seismometers in boreholes will herefore, installing seismometers in boreholes will installing seismometers in boreholes will nstalling seismometers in boreholes will ing seismometers in boreholes will seismometers in boreholes will s in boreholes will will be very important for the study of dynamic processes of for the study of dynamic processes of study of dynamic processes of of dynamic processes of dynamic processes of es of of earthquakes beneath the seafloor.
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Braz. oral res.  vol.24 número1

Braz. oral res. vol.24 número1

To date, there are few studies reporting mean values of proximal enamel thickness for maxillary irst bicuspids. Radiographic assessment of mandib- ular irst bicuspids estimated enamel thickness for mesial and distal surfaces at 0.99 mm and 1.07 mm, respectively. 4 In another study 15 using tooth section-

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J. Appl. Oral Sci.  vol.21 número1

J. Appl. Oral Sci. vol.21 número1

In summary, it was found that titanium disks with moderately rough surfaces tended to exhibit š%$ differences in colonization density between the tested titanium surfaces did not[r]

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Study of superficial properties of titanium treated by PIIID

Study of superficial properties of titanium treated by PIIID

Figure 4 shows the composition and atomic concen- tration, obtained by XPS, of surface of pristine and PI- IID modified titanium samples after immersion in SBF. Although calcium, phosphorus and oxygen, which are el- ements present in hydroxyapatite, have been detected in both samples, their concentrations are higher on the treated material. This result is in accordance with previ- ous works that have shown the improvement of the precipitation of calcium phosphate on calcium-containing titanium surfaces when exposed to physiological solutions [2]. The formation of calcium phosphate is accelerated by ionic exchanges of calcium on the surface by species on the simulated body fluid [9].
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