The Effect of Optical Brightening Agent (OBA) in Paper and Illumination Intensity on Perceptibility of Printed Colors

Widely utilized sanctioned color aims for commercial printing are based on paper substrates without optical brightening agents, also known as OBAs. However, in today\u27s market, more and more paper is manufactured with OBAs. This could be problematic for commercial printers as OBAs influence not only paper conformity, but also the accuracy printed colors. This can lead to color mismatch between proofs and the final prints. Recognizing this condition, the objectives of this research were two-fold: first, to verify the perceived color difference between prints due to the presence of OBAs, and second, to study the perceptibility of color differences caused by OBAs in paper substrates, combined with quantitative measurement assessment. In order to satisfy these objectives, the following research questions were investigated: Does CIEDE 2000(∆E00) correlate better with visual scaling or ranking for color differences of printed color pairs than CIELABDE (∆E*ab)? Do different illuminant intensity levels (ISO 3664 P1: 2000lx and P2: 500lx) affect human perceptibility of color differences for color pairs with dark shades? A psychophysical experiment was carried out for evaluating color differences using printed color patches. In total, 27 pairs of printed color patches derived from the IT8.7/4 Target (1,617 color patches) were prepared using the same colorants printed on paper with and without OBA. Each pair was assessed at two levels of illumination by a panel of thirty-four observers. The visual results were used to investigate the relationship between color difference metrics and visual scaling (ranking) of color differences induced by OBAs, as well as the relationship between illumination intensity level and visual scaling of color samples with high-density. The results indicated that: (a) There is better correlation between ∆E00 and the visual scaling of OBA-induced color differences than ∆E*ab; and (b) there is no association between different illumination intensities (i.e., ISO: 3664 P1, P2) and visual scaling of color differences in high-density areas

The Effect of OBA in Paper and Illumination Level on Perceptibility of Printed Colors

A research was conducted to study the perceptibility of color difference of color pairs, caused by OBA differences in paper substrates, and its relationship with quantitative measurement metrics. Based on the psychometric experiments conducted, the results show the utilization of the visual difference index (VDI), from 0 (no difference) to 3 (noticeable difference), to rate 27 color pairs with each pair prepared by the same colorants but different OBA amount in the substrates. The findings indicate that (a) printed colors are affected by the presence of OBA from no difference to noticeable difference, (b) ∆E00 has a stronger linear correlation with visual color difference than ∆E*ab does, (c) there is no significant association between illumination levels and visual color difference. This research introduces the metric, OBA, per ISO 15397 (2013), as the CIE-b* difference in color pairs under M1 and M2 conditions. It also defines ∆OBA as the OBA difference between any color pairs, including substrates. The results show that there is linear correlation (1) between visual difference and ∆E00 which describes the color difference, and (2) between visual difference and ∆OBA which describes the criticalness of M1 lighting to realize the color match

Positive Solutions of Nonlocal Boundary Value Problem for High-Order Nonlinear Fractional -Difference Equations

We study the nonlinear -difference equations of fractional order ( )( ) + ( , ( )) = 0, 0 < < 1, ( where is the fractional -derivative of the Riemann-Liouville type of order , − 1 < ≤ , > 2, 1 ≤ ≤ − 2, and 0 ≤ ≤ 1. We obtain the existence and multiplicity results of positive solutions by using some fixed point theorems. Finally, we give examples to illustrate the results

A neural network model for semi-supervised review aspect identification

National Research Foundation (NRF) Singapore under International Research Centres in Singapore Funding Initiativ

Kashin Beck Disease: more than just osteoarthrosis

The purpose of this study was to investigate the influence of body function, activities and pain on the level of activity in adults with Kashin Beck Disease (KBD). Seventy-five KBD patients with a mean age of 54.8 years (SD 11.3) participated. Anthropometrics, range of joint motion (ROM) and muscle strength were measured as well as the time-up-and-go test and functional tests for the lower and upper extremities. Activity was assessed with the participation scale and the WHO DAS II. In the shoulder, elbow, hip and knee joints, a severe decrease in ROM and bilateral pain was noted. A decrease in muscle strength was observed in almost all muscles. The timed-up-and-go test scores decreased. No or mild restriction in activity was found in 35%, and 33% experienced a moderate restriction whereas 32% had severe to extreme restriction. Activities in the lower extremities were mildly to moderately correlated to ROM and muscle strength, whereas in the upper extremities activities were correlated to range of joint motion. Activity was significantly associated with ROM after correction for muscle strength, gender and age. Participation was borderline significantly associated with ROM after correction for muscle strength, gender, age and the activity time-up-and-go. In KBD adults, a severe decrease in activity is primarily caused by decrease in ROM. These findings have strong influence on rehabilitation and surgical interventio

The promoting effect of byproducts from Irpex lacteus on subsequent enzymatic hydrolysis of bio-pretreated cornstalks

<p>Abstract</p> <p>Background</p> <p><it>Irpex lacteus</it>, a versatile lignin-degrading fungus with various extracellular enzymes, has been widely used for biological pretreatment. However, most studies have focused on the change of substrate structure after biological pretreatment, and the effect of these changes on the enzymatic hydrolysis, but the effect of byproducts from biological pretreatment process on subsequent enzymatic hydrolysis is not well understood.</p> <p>Methods</p> <p>We developed a biological pretreatment process with <it>I. lacteus </it>that can produce stimulatory byproducts that enhance the enzymatic hydrolysis of cornstalks.</p> <p>Results</p> <p>The maximum hydrolysis yield of glucan (82%) was obtained after pretreatment for 28 days. The maximum reducing sugar yield decreased from 313.5 to 200.1 mg/g raw cornstalks after water-soluble byproducts of biological pretreatment were removed from pretreated cornstalks. The effect of byproducts on enzymatic hydrolysis was also investigated. We found that the hydrolysis efficiency of commercial cellulase preparation on cornstalks could be improved by water extracts from bio-pretreated cornstalks with hydrolytic enzyme activity and iron-reducing activity.</p> <p>Conclusion</p> <p>The key finding suggested that byproducts from biological pretreatment play important roles in enhancing downstream hydrolysis, which might be attributable to hydrolytic enzymes and iron-reducing compounds produced by <it>I. lacteus</it>.</p

Under the Non-Uniform Ground Stress Condition for Simulating the Casing Deformation

To the issue about the casing deformation, the paper main study the casing deformation law under the non-uniform ground stress condition, by the ways that the finite element software. The results of the study shows that under the non-uniform ground stress condition, the casing maximum deformation is parallel to the maximum horizontal stress direction. With the increase of the difference between maximum horizontal stress and minimum horizontal stress, the casing deformation increase gradually. And with the elasticity modulus of rock and the Poisson’s ratio of formation increase, the maximum deformation is lessen. The elasticity modulus of rock have more effect than the Poisson’s ratio of formation. When the elasticity modulus of rock exceed a certain threshold, casing deformation would not be effected by the elasticity modulus of rock.Key words: Non-uniform ground stress; Casing deformation; The elasticity modulus of rock; The Poisson’s ratio of formatio