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1.
Near infrared spectra combined with partial least squares were proposed as a means of non-contact analysis of the adsorptive ink capacity of recording coating materials in ink jet printing. First, the recording coating materials were prepared based on nano silica pigments. 80 samples of the recording coating materials were selected to develop the calibration of adsorptive ink capacity against ink adsorption (g/m2). The model developed predicted samples in the validation set with r2  = 0.80 and SEP  = 1.108, analytical results showed that near infrared spectra had significant potential for the adsorption of ink capacity on the recording coating. The influence of factors such as recording coating thickness, mass ratio silica: binder-polyvinyl alcohol and the solution concentration on the adsorptive ink capacity were studied. With the help of the near infrared spectra, the adsorptive ink capacity of a recording coating material can be rapidly controlled.  相似文献   

2.
Many hosts of the common cuckoo (Cuculus canorus) exhibit egg recognition, and reject parasitic eggs. How do hosts discriminate cuckoo eggs from their own? Hosts might be able to recognize their own eggs using the specific pigment pattern on the outer eggshell surface, which may serve as a cue for recognition. We tested if patterns of egg pigments (spottedness) contain this information by manipulating spot density of great reed warbler eggs (Acrocephalus arundinaceus). We also manipulated the colour of eggs when the original spot pattern remained the same. Spot density (approximately 15–75%) did not significantly affect rejection rate (8–20% rejection), but when spots fully covered the eggs, i.e. the eggshell was plain dark brown, rejection rate increased abruptly to 100%. A loglinear model revealed the significant influence of colour on rejection rates, although there was no interactive effect between spottedness and colour. Our results strongly support the differential use of egg markers in host’s egg discrimination, suggesting that spot density has limited importance compared to eggshell colour.  相似文献   

3.
Recycling of office waste paper (photocopy, inkjet, and laser prints) is a major problem due to difficulty in removal of nonimpact ink. Biological deinking of office waste paper is reported using several microorganisms and their enzymes. We report here deinking and decolorization of the dislodged ink particles from inkjet printed paper pulp by a marine bacterium, Vibrio alginolyticus isolate no. NIO/DI/32, obtained from marine sediments. Decolorization of this pulp was achieved within 72 h by growing the bacterium in the pulp of 3–6% consistency suspended in seawater. Immobilized bacterial cells in sodium alginate beads were also able to decolorize this pulp within 72 h. The cell-free culture supernatant of the bacterium grown in nutrient broth was not effective in deinking. However, when the culture was grown in nutrient broth supplemented with starch or Tween 80, the cell-free culture supernatant could effectively deink and decolorize inkjet-printed paper pulp within 72 h at 30°C. The culture supernatant of V. alginolyticus grown in the presence of starch or Tween 80 showed 49 U ml−1 and 33 U ml−1 amylase and lipase activities, respectively. Dialysis of these culture supernatants through 10 kDa cut-off membrane resulted in a 35–40% reduction in their efficiency in decolorizing the pulp. It appears that amylase and lipase effectively help in dislodging the ink particles from the inkjet printed-paper pulp. We hypothesize that the bacterium might be inducing the formation of low molecular weight free radicals in the culture medium, which might be responsible for decolorization of the pulp.  相似文献   

4.
Modified cellulase with polyoxyethylene was applied to de-ink waste papers and the weight ratio of modified cellulase to paper was varied from 0.05 to 2% (w/w). During mechanical pulping, the cellulase enhanced the detachment of the ink particle from the paper by partial hydrolysis of the fiber. Polyoxyethylene caused foaming and removed the detached ink particles by floatation. The new biological de-inking process improved the physical properties while maintaining the same de-inking ability. Reprocessed paper freeness, whiteness, and tensile strength increased by 31%, 13%, and 24%, respectively.  相似文献   

5.
Infectious diseases and parasitism are major environmental forces decreasing fitness, and thus individual strategies aimed at preventing pathogen infections, either in an individual or their offspring, should be favoured by natural selection. The mineral fraction and some organic compounds in the shells of bird eggs are considered physical and chemical barriers against pathogen penetration to the embryo. However, eggshell pigment deposition has only recently been considered as a mechanism to resist pathogen penetration into the egg. By wiping the eggshell surface, the amount of pigment and some cuticle proteins were experimentally manipulated for the first time in nature. The effects on egg hatchability and offspring viability measured as nestling condition, immunocompetence and probability of recruitment were investigated in the common kestrel Falco tinnunculus. Protoporphyrin IX and biliverdin IXα to a lesser extent were the only identified pigments. The concentration of protoporphyrin IX and cuticle proteins were significantly reduced in the wiped with respect to the control treatment. Our study shows no evidence of a detrimental effect of the reduction of eggshell pigments on egg hatchability, mortality of the chicks during the nesting period, nestling body condition, nestling local immune response to PHA antigen or probability of recruitment. Further research will be necessary to elucidate the direct role of protoporphyrins and other pigments in egg bacterial infection.  相似文献   

6.
Birds'' eggshells are renowned for their striking colours and varied patterns. Although often considered exceptionally diverse, we report that avian eggshell coloration, sampled here across the full phylogenetic diversity of birds, occupies only 0.08–0.10% of the avian perceivable colour space. The concentrations of the two known tetrapyrrole eggshell pigments (protoporphyrin and biliverdin) are generally poor predictors of colour, both intra- and interspecifically. Here, we show that the constrained diversity of eggshell coloration can be accurately predicted by colour mixing models based on the relative contribution of both pigments and we demonstrate that the models'' predictions can be improved by accounting for the reflectance of the eggshell''s calcium carbonate matrix. The establishment of these proximate links between pigmentation and colour will enable future tests of hypotheses on the functions of perceived avian eggshell colours that depend on eggshell chemistry. More generally, colour mixing models are not limited to avian eggshell colours but apply to any natural colour. Our approach illustrates how modelling can aid the understanding of constraints on phenotypic diversity.  相似文献   

7.
Reproduction is a critical period for birds as they have to cope with many stressful events. One consequence of an acute exposure to stress is the release of corticosterone, the avian stress hormone. Prolonged stress can have negative impacts on the immune system, resulting in, for example, increased oxidative stress. Through maternal effects, females are known to modulate their investment in eggs content according to their own physiological condition. Less is known about maternal investment in eggshells, especially in pigments. The two main eggshell pigments may possess opposite antioxidant properties: protoporphyrin (brown) is a pro-oxidant, whereas biliverdin (blue-green) is an antioxidant. In Japanese quail, we know that the deposition of both pigments is related to female body condition. Thus, a chronic stress response may be reflected in eggshell coloration. Using female Japanese quails that lay brown-spotted eggs, we explored whether physiological exposure to corticosterone induces a change in female basal stress and antioxidant factors, and eggshell pigment concentration, spectrophotometric reflectance, and maculation coverage. We supplemented adult females over a 2 week period with either peanut oil (control) or corticosterone (treatment). We collected pre- and post-supplementation eggs and analysed the effect of corticosterone treatment on female physiology and eggshell appearance parameters. Except for corticosterone-fed birds which laid eggs with brighter spots, supplementation had no significant effect on female physiology or eggshell pigment concentration, reflectance and maculation. The change in eggshell spot brightness was not detected by a photoreceptor noise-limited color opponent model of avian visual perception. Our data confirms that eggshell reflectance in spotted eggs varies over the laying sequence, and spot reflectance may be a key factor that is affected by females CORT exposure, even if the changes are not detected by an avian visual model.  相似文献   

8.
The objective of this work was to study the chemical and physical characterization of eggshell and eggshell membrane particles prepared from the hen eggshell waste. Under the characterization measurements investigated, it was found that the pore structures of the two biomaterials belong to a typical Type II, indicating that they should be basically characteristic of nonporous materials or materials with macropores or open voids. Further, the chemical composition of the resulting eggshell particle was strongly associated with the presence of carbonate minerals from the Fourier transform infrared (FTIR) spectra. In contrast to the resulting eggshell membrane particle, the presence of functional groups of amines and amides was observable because of its chemical composition of fibrous proteins. From the isotherm data of methylene blue at 25 degrees C, the Freundlich model yielded a somewhat better fit than the Langmuir model. The adsorption isotherms revealed the eggshell biosorbents could only uptake the basic dye of less than 1.0mg/g in aqueous medium, which was attributed to their poor pore properties.  相似文献   

9.
The colourful appearance of bird eggshells has long fascinated biologists and considerable research effort has focused on the structure and biochemistry of the avian eggshell matrix. The presence of tetrapyrrole pigments was identified nearly a century ago. Surprisingly, how the concentrations of avian eggshell pigments vary among related species, and whether this variability is associated with either eggshell appearance and/or species life‐history traits, remains poorly understood. We quantified the concentrations of the two key eggshell pigments, protoporphyrin IX and biliverdin, from a diverse sample of eggshells stored at the Natural History Museum, Tring, UK. We explicitly tested how these two pigments are associated with physical measures of eggshell coloration and whether the pigment concentrations and colour diversity co‐vary with phylogenetic affiliations among species. We also tested a series of comparative hypotheses regarding the association between the concentrations of the two pigments and specific life‐history and breeding ecology traits. Across species, the average concentrations of protoporphyrin and biliverdin were positively correlated, and both strongly co‐varied with phylogenetic relatedness. Controlling for phylogeny, protoporphyrin concentration was associated with a higher likelihood of cavity nesting and ground nesting, whereas biliverdin concentration was associated with a higher likelihood of non‐cavity nesting habit and bi‐parental provisioning. Although unlikely to be explained by a single function, the breeding ecology and life history‐dependence of eggshell pigment concentrations in these comparative analyses implies that related species share pigment strategies, and that those strategies relate to broad adaptive roles in the evolution of variation in avian eggshell coloration and its underlying mechanisms. © 2012 The Linnean Society of London, Biological Journal of the Linnean Society, 2012, 106 , 657–672.  相似文献   

10.
Current research into the evolution and adaptive function of avian eggshell pigmentation, including maculation, has focused mostly on signalling‐based and structural function hypotheses but ignored the potential consequences of shell pigmentation for the developing avian embryo, especially in moderating the embryo's interaction with its light environment. The exposure of the eggs to sunlight that frequently accompanies avian incubation behaviour is one of the major evolutionary steps setting apart birds and reptiles, and coincides with the appearance of eggshell pigmentation. This suggests that shell pigments could play a major role in ensuring the successful development of the avian embryo. We propose that the effects of shell pigments on the egg contents should be considered in addition to established hypotheses of shell pigmentation such as crypsis, egg recognition or a possible structural function. This approach has the potential to identify trade‐offs between different pigment functions and to resolve some of the long standing paradoxa in the evolution of eggshell colour, such as the occurrence of conspicuous blue eggs in passerines or the secondary evolution of white eggshells in cavity nesters. In particular, we identify seven hypotheses, which address how the interaction of eggshell pigments and the light environment may influence embryonic development. These hypotheses are the: thermo‐regulation; UV‐B protection; photo‐acceleration; lateralization; circadian rhythm; photo‐reactivation; and antimicrobial defence. We believe that the understanding of eggshell pigmentation will greatly benefit from taking these hypotheses into consideration when studying the functional significance of eggshell pigmentation and suggest a number of promising directions for future experimental and comparative research.  相似文献   

11.
Homogenates of male rat hypothalami were fractionated by means of differential centrifugation, and α-melanocyte-stimulating hormone (α-MSH) in the various fractions was quantified by radioimmunoassay. Of the total quantity of α-MSH in the homogenate, 36% was recovered in the 11,500 g pellet and 31% sedimented between 11,500 and 105,000 g. α-MSH was not detected in the 105,000 g supernatant fluid. When the 900 g supernatant fluid was fractionated on continuous sucrose density gradients at non-equilibrium conditions, two populations of particles containing α-MSH were observed. When fractionated at equilibrium conditions, the two populations were recovered in a single band. These sedimentation characteristics indicate that the particles that contain α-MSH differ in size but are similar in density. After hypo-osmotic shock, the large particles containing α-MSH were not demonstrable, whereas the small particles appeared to be resistant to such treatment. In their sedimentation, the particles containing α-MSH were indistinguishable from particles containing thyrotropin releasing hormone (TRH) but were separable from those that contained luteinizing hormone releasing hormone (LHRH). It is suggested that the large particles containing α-MSH are synaptosomes.  相似文献   

12.
Oviparous animals have evolved multiple defenses to prevent microbes from penetrating their eggs and causing embryo mortality. In birds, egg constituents such as lysozyme and antibodies defend against microbial infestation, but eggshell pigments might also impact survival of bacteria. If so, microbes could exert an important selective pressure on the evolution of eggshell coloration. In a previous lab experiment, eggshell protoporphyrin caused drastic mortality in cultures of Gram positive, but not Gram negative, bacteria when exposed to light. Here, we test this “photodynamic antimicrobial hypothesis” in a field experiment. In a paired experimental design, we placed sanitized brown, protoporphyrin‐rich chicken eggs alongside white eggs that lack protoporphyrin. We deployed eggs for 48 hr without incubation, as can occur between laying and incubation, when microbial infection risk is highest. Eggs were placed on the open ground exposed to sunlight and in dark underground storm‐petrel burrows. We predicted that the proportion of Gram‐positive bacteria on brown eggs should be lower when exposed to sunlight than when kept in the dark, but we expected no such difference for white eggs. Although our data revealed variation in bacterial community composition, the proportion of Gram‐positive bacteria on eggshells did not vary by egg color, and there was no interaction between egg color and location. Instead, Gram‐positive bacteria were proportionally more common on eggs on the ground than eggs in burrows. Overall, our experiment did not support the photodynamic antimicrobial hypothesis. The diverse range of avian egg colors is generated by just two pigments, but over 10 hypotheses have been proposed for the evolution of eggshell color. If our results are generalizable, eggshell protoporphyrin might not play a substantial role in defending eggs against microbes, which narrows the field of candidate hypotheses for the evolution of avian eggshell coloration.  相似文献   

13.
《Journal of biotechnology》1999,67(2-3):229-236
A screening of different strains of bacteria for the production of lipases which degrade the soy bean oil based binder component of newsprint ink was performed. Three strains were found to be efficient lipase producers and were selected for further investigations. The pH optimum, temperature stability and the optimum enzyme concentrations for the deinking of recovered paper printed with soy bean oil based ink were determined and compared with a commercially available porcine pancreas lipase preparation. A lipase preparation from Pseudomonas aeruginosa with a pH optimum and temperature stability suitable for an application in a deinking process and with a high deinking efficiency in combination with a neutral surfactant could be identified. The deinking effect of the lipases was caused by a partial degradation of the binder of the soy bean oil based inks thereby releasing the ink particles from the paper.  相似文献   

14.
The use of enzymes has been suggested as an environmentally friendly alternative to complement conventional chemical deinking in the recycling of recovered paper. This study compares the use of cellulases/hemicellulases versus the laccase-mediator system for deinking printed fibers from newspapers and magazines. For this purpose, two commercial enzyme preparations with endoglucanase and endoxylanase activities (Viscozyme Wheat from Aspergillus oryzae and Ultraflo L from Humicola insolens, Novozymes) and a commercial laccase (NS51002 from Trametes villosa, Novozymes), the latter in the presence of synthetic or natural (lignin-related) mediators, were evaluated. The enzymatic treatments were studied at the laboratory scale using a standard chemical deinking sequence consisting of a pulping stage; an alkaline stage using NaOH, sodium silicate and fatty acid soap; and a bleaching stage using hydrogen peroxide. The handsheets were then prepared and their brightness, residual ink concentration, and strength properties were measured. Among the different enzymatic treatments assayed, both carbohydrate hydrolases were found to deink the secondary fibers more efficiently. Brightness increased up to 3–4% ISO on newspaper fibers, being Ultraflo 20% more efficient in the ink removal. Up to 2.5% ISO brightness increase was obtained when magazine fibers were used, being Viscozyme 9% more efficient in the ink removal. Regarding the laccase-mediator system, alone or in combination with carbohydrate hydrolases, it was ineffective in deinking both newspaper and magazine fibers, resulting in pulps with worse brightness and residual ink concentration values. However, pulp deinking by the laccase-mediator system was displayed when secondary fibers from printed cardboard were used, obtaining up to 3% ISO brightness increase and lower residual ink concentrations.  相似文献   

15.
Abstract— A 10% homogenate of male rat hypothalami, prepared in 0.32M-sucrose-10μM-CaCl2, was diluted either with one volume of 0.32M-sucrose-10μM-CaCl2 (iso-osmotic) or with 10μM-CaCl2 (hypo-osmotic). A 900 g supernatant fluid fraction (0.9 K-S) was prepared from the diluted homogenates and fractionated on continuous sucrose density gradients under non-equilibrium and equilibrium conditions. In the iso-osmotic 0.9 K-S thyrotropin releasing hormone (TRH), α-melanocyte stimulating hormone (α-MSH), and luteinizing hormone releasing hormone (LHRH) were each found to be sequestered in two populations of particles which were different in size but similar in density. In the hypo-osmotic 0.9 K-S, TRH, α-MSH, and LHRH were each found to be sequestered in a single population of particles. In their sedimentation properties (as judged by differential, non-equilibrium, and equilibrium density centrifugations), the hypo-osmotically resistant particles and the small particles present in the iso-osmotic 0.9 K-S were identical. However, in their peptide content, the two sets of particles differed from each other. If the total quantity of particle-bound peptides recovered after gradient centrifugation of the iso-osmotic 0.9 K-S is taken as 100%, one finds that the amount of TRH, α-MSH. and LHRH recovered in the small particles is 39%, 50%, and 39%. respectively, whereas the amount of TRH, a-MSH, and LHRH recovered in the hypo-osmotically resistant particles is 42%, 68%, and 67%, respectively. This increase in the quantity of peptides sequestered in the small particles occurred concomitantly with the disappearance of peptides from the large synaptosome-like particles. It is estimated that within the large synaptosome-like particles 7% of the TRH, 35% of the a-MSH, and 45% of the LHRH are associated with hypo-osmotically resistant particles. Ultrastructural analysis of purified hypo-osmotically resistant particles containing TRH. α-MSH. or LHRH revealed a predominance of membrane-bounded packets of electron-dense material.  相似文献   

16.

In this study, linear and mass attenuation coefficients of fabricated particleboards intended for use as phantom material were estimated using 137Cs and 60Co radiation sources. Particleboards made of Rhizophora spp. wood trunk bonded with soy flour and lignin were fabricated at a target density of 1.0 g cm?3, with and without gloss finish coating. Elemental composition of the particleboards was obtained by means of energy dispersive X-ray (EDX) spectroscopy. Experimental setups were simulated via the GATE Monte Carlo (MC) package, with particle histories of 1?×?106–1?×?107. Linear and mass attenuation coefficients obtained from measurements and GATE simulations were compared and discussed. The percentage differences between the measured and simulated linear and mass attenuation coefficients of the samples were reasonably small (2.05–4.88% for 137Cs and 3.24–5.38% for 60Co). It is shown that all the particleboards have the potential to be used as phantom materials as the attenuation coefficients measured were in good agreement with those of water (calculated with XCOM) and with those simulated with the GATE toolkit. The use of gloss finish coating also did not show any significant effect on the attenuation coefficient of the phantom material. Verification of experimental results via GATE simulations has been shown crucial in providing reliable data for energy transmission studies. Based on the results achieved in this study, it is concluded that the studied material—Rhizophora spp. wood trunk bonded with soy flour and lignin including gloss finish coating—can be used in radiation dosimetry studies.

  相似文献   

17.
Brood parasites lay unusually strong eggs, presumably to prevent puncture ejection of the eggs by hosts. However, it has been suggested that eggs of some parasitic cuckoos have normal strength. This suggestion was based on the eggshell thickness and shape of these eggs. Here, we propose that there may be other structural adaptations (such as increased eggshell density) that make the cuckoo eggs unusually strong. In this study, we compared the eggshell density of parasitic cuckoos to the eggshell density of two control groups, non-parasitic cuckoos and a sample of non-passerine species. The comparisons to both control groups demonstrated that the parasitic cuckoos have eggshells of significantly higher density than would be expected for their size. Our results support the hypothesis that the higher eggshell density is an alternative mechanism by which some cuckoos increase the strength of their eggs.  相似文献   

18.
In order to assess the effect of opioid receptor antagonists, naloxone and noradrenaline, on renal cortical microcirculation, India ink infusion was made through the renal artery, one hour after treatment with each drug, in dogs subjected to haemorrhagic shock. Naloxone (1 mg/kg) treatment showed a dual beneficial effect of significant improvement (P < 0.001) in the mean arterial pressure without increasing the renal resistance as indicated by the presence of ink particles in about 75% of the cortical glomeruli. However, in the case of noradrenaline (2 Μ/kg/min)-treated animals, although mean arterial pressure increased significantly (P < 0.001) only very few glomeruli (25%) in the cortical region showed ink particles, demonstrating severe vasoconstriction. In the control group infused only with saline, although most of the glomeruli (92%) were filled with ink particles, there was a significant decline in the mean arterial pressure (P < 0.001).  相似文献   

19.
Efficient use of shrimp waste: present and future trends   总被引:2,自引:0,他引:2  
The production of shrimp waste from shrimp processing industries has undergone a dramatic increase in recent years. Continued production of this biomaterial without corresponding development of utilizing technology has resulted in waste collection, disposal, and pollution problems. Currently used chemical process releases toxic chemicals such as HCl, acetic acid, and NaOH into aquatic ecosystem as byproducts which will spoil the aquatic flora and fauna. Environmental protection regulations have become stricter. Now, there is a need to treat and utilize the waste in most efficient manner. The shrimp waste contains several bioactive compounds such as chitin, pigments, amino acids, and fatty acids. These bioactive compounds have a wide range of applications including medical, therapies, cosmetics, paper, pulp and textile industries, biotechnology, and food applications. This current review article present the utilization of shrimp waste as well as an alternative technology to replace hazardous chemical method that address the future trends in total utilization of shrimp waste for recovery of bioactive compounds.  相似文献   

20.
The striking variation in colour and maculation of bird eggs has fascinated biologists since centuries, and many hypotheses based on mechanical, physiological or signalling functions have been proposed for its evolution by natural and sexual selection. Protoporphyrin is the main eggshell pigment found in brown maculated eggs, and is assumed to function as a mediator of these selection processes. It is a precursor of heme with pro‐oxidant properties, and hence a link between brown maculation and female condition has been proposed and tested in a number of studies, albeit with contrasting results. A variety of different visual methods have been used to quantify outer eggshell pigmentation, which has been assumed to correspond to overall quantity of protoporphyrin in the shell. Yet, this relationship has rarely been tested. The aim of this study was to apply four commonly used methods to assess pigmentation in great tit eggs with protoporphyrin as the predominant eggshell pigment, and to compare the results of these methods. Specifically, we 1) ranked eggshell pigmentation by human naked eye, 2) applied a granularity approach and 3) measured spectrophotometric reflectance of eggshell pigments. Second, we estimated the relationship between outer eggshell pigmentation (i.e. estimated by three different methods above) and true protoporphyrin concentration deposited in the entire shell measured by HPLC. Among‐method estimates were significantly correlated for the traits describing pigment ‘darkness’ only. While the model including scores based on human naked eyes explained 16% of the variance of pigment concentration in the entire shell, spectrometry explained 27%, and the granularity approach explained 40%. Thus, the estimation of true pigment concentration in the entire shell from the visible outer side of the shell is most reliable with the granularity approach. It is relevant for studies where the maintenance of the integrity of the eggs is essential.  相似文献   

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