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101.
The objective of this research was to evaluate the rheological and textural properties of gluten-free doughs based on potato starch, which was partially substituted by different proportions of quinoa (10%, 30% and 50%), kiwicha (10%, 30% and 50%) or tarwi flour (10%, 20% and 30%). The influence of the substitution on the kinetics of the leavening process was studied as well. The back-extrusion technique was used to determine rheological and textural properties of the dough, and the leavening kinetics were modelled using the Gompertz equation. The results showed that textural properties such as firmness, consistency, cohesiveness and viscosity index, as well as the consistency index of the doughs increased as the level of substitution of the Andean grain flour in the formulation increased. It was determined that the formulations with an addition of 10% and 20% for quinoa or kiwicha flour, and 10% for tarwi flour would be most suitable for developing gluten-free breads.  相似文献   
102.
The building sector consumes large quantities of resources and generates high levels of construction and demolition (C&D) waste. From an ‘urban mining’ perspective, the building stock can be seen as a repository of natural resources. In order to manage this repository, evidence is needed on its quantity and dynamics. Although data exist for domestic buildings, little evidence exists for non-domestic buildings. A new method is presented to quantify the material stock of non-domestic buildings – based on the German building stock. The quantification process involves three steps: (1) material composition indicators (MCIs) are calculated with respect to various building types; (2) the country's total floor space is estimated and disaggregated; and (3) the total material stock is calculated. The main results are MCIs and the floor space for both domestic and non-domestic stocks, as well as the material mass in total. In Germany the total material mass of non-domestic buildings is approximately 6.8 billion tonnes, accounting for 44% of the entire building stock. The method can be adapted and validated for use in other countries. These results will assist both policy-makers and the construction industry to understand the potential for moving toward a more circular economy.  相似文献   
103.
Green plantain flour (GPF) is rich in indigestible carbohydrates, especially in resistant starch (RS). The objective of this study was to improve the functional pasta properties and RS content by producing gluten‐free (GF) pasta based on rice flour with different amounts of GPF addition (15–60% of total flour blend). Egg albumen (3.5–6.0% of total flour) and dough moisture (36–40%, dough humidity%), at constant emulsifier (0.5% of total flour) addition, were optimised in the first trials. The results showed that an addition up to 30% GPF with higher amount of egg albumen (6%) at dough moisture of 38% provided pasta with acceptable cooking quality and high RS content. Some qualities and/or RS content of GF pasta samples was further improved by adding 30% pregelatinised flours from the native GPF or drum‐dried green banana flour (DDGBF) in combination with applying varied steps of cooking and/or cooling, which were applied after pasta extrusion prior to drying them. The study suggests that GPF, in its native form, but particularly when pregelatinised, is a promising ingredient to be used for the production of GF pasta.  相似文献   
104.
Tickborne encephalitis, a zoonotic virus infection, is transmitted to humans usually by the bite of an infected tick. It may also be acquired by ingesting infected dairy products. In this study, the infectivity of tickborne encephalitis virus, suspended in milk and other media, remained unchanged during a period of five days of storage at 8 °C. After heat treatments in the range of 60 to 80 °C, a decrease of approximately 4 or 4.5 log units in the virus titre was observed. Kinetic parameters for the inactivation were calculated, and the line of equal effects showing a 3‐log inactivation was determined.  相似文献   
105.
Our objective was to test the hypothesis that the pheromone blend and/or diel periodicity of pheromonal communication differ in populations of the nun moth, Lymantria monacha(Lepidoptera: Lymantriidae), from eastern Asia (northern Honshu, Japan) and Central Europe (Bohemia, Czech Republic). Coupled gas chromatographic–electroantennographic detection (GC-EAD) analyses of pheromone gland extract of female L. monachafrom Japan confirmed the presence of compounds previously identified in pheromone extracts of L. monachafrom Bohemia, as follows: (Z)-7-octadecene, 2-methyl-(Z)-7-octadecene (2me-Z7–18Hy), cis-7,8-epoxy-octadecane (monachalure), and cis-7,8-epoxy-2-methyloctadecane (disparlure). Field experiments in Honshu suggested that (+)-monachalure is the major pheromone component of L. monacha. 2me-Z7–18Hy significantly enhanced attractiveness of (+)-monachalure. Addition of (+)-disparlure to (+)-monachalure plus 2me-Z7–18Hy in Honshu and Bohemia increased attractiveness of lures by 1.2 and 20 times, respectively, indicating that (+)-disparlure is of least and most significance in the respective L. monachapopulations. Moreover, capture of male L. monachain pheromone-baited traps between 18:00 and 24:00 hr in Bohemia and 2:00 and 5:00 hr in Honshu revealed a markedly different diel periodicity of pheromonal communication. Pheromonal communication late at night and use of (+)-monachalure, rather than (+)-disparlure, as the major pheromone component by L. monachain Honshu may have resulted from interspecific competition with coseasonal L. fumida, which uses the early night for pheromonal communication and (+)-disparlure as major pheromone component. Whether communication channel divergence of L. monachain Honshu indeed constitutes a case of reproductive character displacement is difficult to prove. The evolution of such divergence in sympatricpopulations of L. fumidaand L. monachawould have to be demonstrated.  相似文献   
106.
We identified and field-tested the sex pheromones of Dasineura oxycoccana (Johnson) (Diptera: Cecidomyiidae) midges collected from cranberry, Vaccinium macrocarpon Aiton, and from highbush blueberry, Vaccinium corymbosum L., commonly named cranberry tipworm (CTW) and blueberry gall midge (BGM), respectively. Coupled gas chromatographic-electroantennographic detection (GC-EAD) analyses of pheromone gland extract from the ovipositor of calling CTW females revealed one component (<10 pg per ovipositor/pheromone gland) that elicited antennal responses from CTW males. Stepwise identification was based on its mass spectrum in a concentrated sample with 300 pheromone gland equivalents, retention indices (RI) on three GC columns (DB-5, DB-23, and DB 210), RI inter-column differentials, and RIs and double bond positions of other midge pheromones. These analyses indicated that (8Z)-2,14-diacetoxy-8-heptadecene (2,14-8Z-17) was the candidate pheromone of the CTW. GC-EAD analysis of pheromone gland extract from calling BGM females revealed two components that elicited antennal responses from BGM males. Retention times on the three GC columns were consistent with 2,14-8Z-17 and 2,14-17, indicating that these were candidate pheromone components of the BGM. The four stereoisomers of 2,14-8Z-17 were stereoselectively synthesized and field-tested in cranberry. Delta-type traps baited with SS-2,14-8Z-17 captured significantly more CTW males than did traps baited with any other single stereoisomer or with all four stereoisomers combined. In blueberry, delta-type traps baited with RR-2,14-8Z-17 captured significantly more BGM males than did traps baited with any other single stereoisomer or with all four stereoisomers combined. Subsequent field experiments demonstrated that RR-2,14-17 is the major pheromone component of BGM, and that RR-2,14-8Z-17 is a pheromone component that does not enhance attractiveness of RR-2,14-17. The BGM pheromone RR-2,14-17 has no antagonistic effect on the CTW pheromone SS-2,14-8Z-17 and vice versa. Our results substantiate the conclusion that populations of D. oxycoccana on cranberry and blueberry represent two cryptic species.  相似文献   
107.
108.
The enzymatic characterization of 100 strains of Vibrio isolated from the hemolymph of Litopenaeus vannamei was performed. All the strains were subjected to caseinase (Cas), gelatinase (Gel), elastase (Elas), phospholipase (Phos), lipase (Lip) and β-hemolysis detection. The enzymatic profile indicated the following positivity indices: 96 % of the isolates were Cas+, 80 % Gel+, 35 % Elas+, 94 % Phos+, 58 % Lip+, and 38 % expressed the ability to produce β-hemolysis in sheep erythrocytes. Coincidental exoenzymatic expression was observed in 99 % of the isolates, and the profiles GelCasPhos (16 %) and GelCasPhosLip (16 %) were the most frequent. Additional enzymatic activity experiments in 24 strains showed a positivity index higher than 90 % for esterase (C4), leucine arylamidase, acid phosphatase and alkaline phosphatase.  相似文献   
109.
110.
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