Poultry feathers make up for as much as 8.5% of chicken weight and represent a considerable amount of almost pure keratin waste which is not being adequately utilized at the present time. The present study dealt with the processing of poultry feathers through a two-stage alkaline-enzymatic hydrolysis. In the first stage, feathers were mixed with a 0.1 or 0.3% KOH water solution in a 1 : 50 ratio and were incubated at 70C for 24 h. After adjusting pH to 9, the effects examined in the second processing stage on the amount of degraded feathers were those of proteolytic enzyme additions (1-5%), time (4-8 h) and temperature (50-70C). Processing feathers in 0.3% KOH and hydrolysing for 8 h in the second stage at 70C with a 5% dose of enzyme (relative to dry feathers weight) produced approx. 91% degradation. Keratin hydrolysate is distinct for its high nitrogen content and reasonable inorganic solids level. Two-stage technology of alkaline-enzymatic hydrolysing of poultry feathers in an environment of 0.3% KOH achieves high efficiency under quite mild reaction conditions (temperature not exceeding 70C with pH in a mildly alkaline region), and is feasible from an economic viewpoint. Keratin hydrolysate can find particular application in packaging technology (films, foils and encapsulates).
The Weight Of Feathers Epub To Pdf
An important requirement of flight is a low body weight. As body weight increases, the muscle output required for flying increases. The largest living bird is the ostrich, and while it is much smaller than the largest mammals, it is flightless. For birds that do fly, reduction in body weight makes flight easier. Several modifications are found in birds to reduce body weight, including pneumatization of bones. Pneumatic bones are bones that are hollow, rather than filled with tissue (Figure). They contain air spaces that are sometimes connected to air sacs, and they have struts of bone to provide structural reinforcement. Pneumatic bones are not found in all birds, and they are more extensive in large birds than in small birds. Not all bones of the skeleton are pneumatic, although the skulls of almost all birds are.
Other modifications that reduce weight include the lack of a urinary bladder. Birds possess a cloaca, a structure that allows water to be reabsorbed from waste back into the bloodstream. Uric acid is not expelled as a liquid but is concentrated into urate salts, which are expelled along with fecal matter. In this way, water is not held in the urinary bladder, which would increase body weight. Most bird species only possess one ovary rather than two, further reducing body mass.
Even without the signs, without any of them, she could have tracked the unicorn. She often had, in the past. When it was younger. When it was more cunning. She had learned to rely on her intuition, on her sense of the unicorn, on the weight of the hunt that hung, like her spear, across her back. And while she had not yet caught it, she had always found it.
The main symptoms of the patients were respiratory symptoms: 3 patients had a chronic dry cough, 2 patients had chest pain, 1 patient had fever, and 2 patients had hemoptysis during the course of chronic cough and wasting. The disease course was long. All 8 patients had received anti-inflammatory and anti-tuberculosis treatments. The symptoms repeatedly occurred without any obvious improvement. The patients were in poor spirits, had normal bowel movements, and experienced significant weight loss.
Paragonimiasis is a systemic chronic parasitic disease. It is a natural focal disease and one of the food-borne parasitic diseases that are harmful to both humans and animals [4]. Paragonimiasis is widely distributed. Blair et al. have shown that the disease is widely distributed in many countries and regions in Asia, Africa, and the Americas, and it is estimated that 292.8 million people in the world are at risk of paragonimiasis [1]. Humans become infected with Paragonimus mainly through the consumption of raw or semi-raw freshwater crabs containing metacercaria [3]. The Dai people are the main ethnic minority living in Xishuangbanna. They eat raw freshwater crabs. In Xishuangbanna, the incidence of paragonimiasis is high, but the detection rate is low. The lung is the most common site of Paragonimus infection [5]. Due to the nonspecific clinical manifestations of the disease in the early stage, patients often do not go to a hospital until the late stages of disease infection, when the manifest symptoms such as hemoptysis and weight loss. In this study, the 8 patients had thoracic and lung type paragonimiasis.
The diancui technique was complex and delicate. Craftsman pasted micron-sized feather fibers on a support and adjusted the microscopic structure and materials with subtle skills to obtain various textural and color effects. This demonstrated a high level of artistic achievement. Due to the rarity of kingfisher feathers, objects with diancui have always been deluxe artworks from ancient China and now appear in many museum and private collections around the world [6,7,8,9].
Although featherwork has recently been the subject of academic attention, research on this important Chinese tradition is comparatively sparse. Although some studies have led to significant results related to the history, technique and conservation of diancui [4, 5, 7, 10], some key historical details are still not clear, especially the details of the complex technique. For example, (1) although only two kinds of kingfisher feathers (blue and violet) were used in diancui, obviously the ancient craftsman could slightly adjust the color and texture of the finishing surface to achieve a rich and vivid decorative effect. What skills did they use? (2) What materials and techniques were used in the supports and adhesives of diancui objects? These lie under the feather layer and are difficult to observe directly. (3) On some ornately decorated objects, both diancui and other kinds of feathers with different colors were used in different areas to enrich colors and patterns. What other feathers were used? Was the technique the same as that used with kingfisher feathers?
Most parts of the screen were in good condition. Therefore, only nondestructive analysis without sampling was acceptable. However, a small leaf part dropped from the screen (Fig. 2) could be used for microsampling before it was restored and reattached. In addition, a small fragment from the ground area could be used for cross section analysis. Modern kingfisher feathers were also compared with feathers from the screen.
There are a variety of methods for feather identification, such as classical taxonomy, microscopy with statistics, and molecular biology [11,12,13]. In this case, the feathers are fragments but not complete, so the classical taxonomy method was inapplicable. Molecular biology methods require sampling, which limits their application. Therefore, microscopic features of the feathers were compared with those in the literature and standard samples for identification.
In this investigation, the details of the materials and techniques used for this hanging screen became clear. Four kinds of feathers were used in this screen. Microscopic identification showed that the light blue and violet areas were both made of kingfisher feathers. The color is a constant unordered structural color but is not dyed. Peacock feather was used in the ground area. The feathers of tree trunk areas are a variety of down feathers. To date, there are no accurate results because sampling is not allowed.
The structure of this diancui contains mainly of three kinds of layers: feather layer, glue and color layers and support body. The feather layer is on the surface. The base body is the supporting structure and is made of bamboo paper. Protein material was used for bonding paper together and sealing the back of the support body. A copper stick was sandwiched in the paper layers to strengthen the body. The glue and color layers have two functions. One involves bonding the feather fibers and the base body together. The other involves adjusting the sensorial color and texture. Light blue feathers were always used together with a black background color. Violet feathers were always used together with a red background color.
In addition to kingfisher feathers, peacock feathers were used to decorate the ground areas of the screen. The main structure of this area is similar to that of the diancui area. The difference is mainly in the background color layer. In this area, silver foil was used for background. The feather was pasted on the silver foil with yellow transparent protein glue, which made the foil look like gold. In addition, changing the gap between feather fibers could be used to fine tune the macroscopic color, which has also been documented by Paulson and Chase and McCarthy [7].
Light blue feathers were the most commonly used material in diancui. Fortunately, the dropped leaf part from the screen was light blue and could be analyzed entirely. As shown by the damaged part (Fig. 3a, c) and flank side (Fig. 3b), there are 6 layers in this part, as shown in Fig. 3d. The results of analytical investigations are shown for every layer in Table 1.
Layer 1: Layer 1 is the surface feather layer. It is obvious that this layer was spliced together with small pieces of feather because the seams could be found through microscopy (Fig. 3a). There is a golden line decoration on Layer 1. According to XRF results (Fig. 4a), the main element of this line is Au, and it also contains small amounts of silver. The XRF signals for Fe, Ga, Si, K, Sr and Zr may be from layers under the golden line because they can also be found in the feather area. To identify whether the feather is from a kingfisher, microscopic methods were used to compare them with examples from the literature and with modern kingfisher feathers. Results showed that they matched well.
On this screen, the stones, beaks and wings of the birds were made of violet kingfisher feathers. In contrast to the light blue area, Fig. 12 shows that the back glue layer of the violet feather was transparent, and the background color layer was red. This design made the sensorial color of the diancui surface brighter. An interesting discovery was that the feathers of bird beaks (Fig. 12a) were sparser than those of other parts (Fig. 12b), so the colors of the beak areas look redder and close to rosy. Obviously, this was not an accident. This discovery means that ancient craftsmen changed the gaps between feather fibers to adjust the overall color. The XRF results show that the main elements of the red layer are Fe, Al and Si, so the red pigment may be ochre. Further analysis was not carried out because sampling was not allowed. 2ff7e9595c
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