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601.
Breads with a specific volume up to, and beyond, that of conventional wheat bread can be made with rice flour (which does not contain gluten) by incorporation of hydroxypropylmethylcellulose (HPMC) and ispaghula husk (isabgol) from Plantago ovata Forsk. Isabgol disperses to a fibrillar ‘weak gel’ network stable over the temperature range of proving (fermentation with yeast) and initial heating in the baking oven. Weakening of the isabgol network at higher temperature is accompanied by thermal gelation of HPMC, so that the overall network strength (storage modulus, G′) remains virtually constant, and the gascell structure developed during proving is retained. Gelation of HPMC (and of methylcellulose) involves two distinct processes which we suggest correspond to partial dissociation and subsequent aggregation of cellulosic ‘bundles’ present in the solution state at low temperature, a mechanism directly analogous to the thermal gelation of globular proteins. 相似文献
602.
The dielectric response of sheep horn has been measured in the frequency range from 10–3–105 Hz and over temperatures in the range 304–500 K. The dynamic behaviour of the conductance and capacitance in sheep horn has been observed to follow fractional power law dependences on frequency. It is shown that the over all dielectric response of these dead cells correspond to a dispersive imperfect bulk in series with a dispersive barrier region. It is further shown that the increase in temperature influences the reponse by eliminating the room temperature dc conductance and affecting the magnitude of the dispersion in capacitance. The magnitudes of activation energies are found as 0.33±0.02 eV for conductance, 0.40±0.02 eV for relaxation and 0.33±0.02 eV for the frequency shift. 相似文献
603.
The present paper is based on the results of a study conducted to investigate whether the relationship between perceived workload and quality of performance, if any, holds true if controlled for shift system, type of task, age, and skill level of the workers. The sample of the study comprised 279 blue-collar workers of a jute industry operating under fixed three-shift system. The subjects were all males selected by random sampling method. The method of data collection was a field study through questionnaire. The collected data were analyzed by employing zero-order and partial correlation coefficients. The results indicate that workload and performance were negatively correlated but the strength of the relationship reduced substantially when the effects of the control variables were partialled out simultaneously. It was concluded that the control variables had joint effect on the relationship between workload and performance but skill level of the employees appeared to be the variable having the greatest contaminating effect. 相似文献
604.
Nikhat Manzoor Md Mahfuzul Haque Luqman A. Khan 《Journal of plant biochemistry and biotechnology.》2004,13(1):65-67
Vanadate, a potent inhibitor of P-type ATPases, reduces the electrochemical gradient considerably. H+-extrusion in cells of Candida albicans, a pathogenic yeast, was strongly inhibited in the presence of 25mM phosphocreatine (PCr) by about 83%. H+-extrusion was further inhibited by 25 mM PCr in the presence of vanadate; 89% with 1 mM, 92% with 2 mM and 99% with 5 mM vanadate. 2 mM vanadate caused 90%, 92% and 96% inhibition in the presence of 20 mM, 30 mM and 40 mM PCr, respectively. Creatine (Cr) had a negligible effect on H+ - extrusion. The inhibition caused by 1 mM, 2 mM and 5 mM vanadate alone was 66%, 77% and 88%, respectively. PCr and vanadate inhibit proton extrusion with almost equal magnitude. It can be concluded that phosphate moiety of PCr interacts with the ATPase and is similar to vanadate interaction. Since PCr is having such a drastic inhibitory effect on ATPase activity we can say that it is playing a significant role in holding a check on this pathogenic fungus in healthy human hosts. 相似文献
605.
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608.
M. S. Haque 《Journal of Zoology》1975,176(1):27-38
The non-resinous secretions, both waxy and non-waxy, are all produced by specialized epidermal cells. 相似文献
609.
M Haque K A Rashid M S Stern P K Sharma A H Siddiqi S N Vinogradov D A Walz 《Comparative biochemistry and physiology. B, Comparative biochemistry》1992,101(4):673-676
1. Gastrothylax crumenifer and Paramphistomum epiclitum parasitize the water buffalo Bubalus bubalis. 2. Gastrothylas hemoglobin consisted of two fractions of ca 30,000 and ca 18,000 by gel filtration. SDS-electrophoresis showed both to be single, ca 15,000 chains. 3. Paramphistomum hemoglobin was ca 16,000 by both gel filtration and SDS-electrophoresis. 4. Reversed-phase chromatography of carboxymethylated trematode and buffalo globins gave single peaks and two peaks, respectively. Although Paramphistomum hemoglobin provided and N-terminal sequence, Gastrothylax hemoglobin did not, suggesting blocked N-terminals. The buffalo sequences were found to be identical to the sequences of the alpha and beta chains of bovine hemoglobin. 5. Although Paramphistomum hemoglobin consists of only one chain, Gastrothylax hemoglobin consists either of one chain which aggregates to a dimer or of two different chains, only one of which aggregates to a dimer. 相似文献
610.
Mainul Haque 《Bulletin of mathematical biology》2009,71(2):430-452
Ratio-dependent predator-prey models are increasingly favored by both the theoretical and experimental ecologists as a more
suitable alternative to describe predator-prey interactions when the predators hunt seriously. In this article, the classical
Bazykin’s model is modified with ratio-dependent functional response. Stability and bifurcation situations of the system are
observed. Since the ratio-dependent model always has difficult dynamics in the vicinity of the origin, the analytical behavior
of the system near origin is studied completely. It is found that paradox of enrichment can happen to this system under certain
parameter values, although the functional response is ratio-dependent. The parametric space for Turing spatial structure is
determined. We also conclude that competition among the predator population might be beneficial for predator species under
certain circumstances. Finally, ecological interpretations of our results are presented in the discussion section. 相似文献