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731.
In this work, we present a pedagogical tumour growth example, in which we apply calibration and validation techniques to an uncertain, Gompertzian model of tumour spheroid growth. The key contribution of this article is the discussion and application of these methods (that are not commonly employed in the field of cancer modelling) in the context of a simple model, whose deterministic analogue is widely known within the community. In the course of the example, we calibrate the model against experimental data that are subject to measurement errors, and then validate the resulting uncertain model predictions. We then analyse the sensitivity of the model predictions to the underlying measurement model. Finally, we propose an elementary learning approach for tuning a threshold parameter in the validation procedure in order to maximize predictive accuracy of our validated model.  相似文献   
732.
V. Kannan  S. V. Job 《Hydrobiologia》1980,69(3):267-271
The phytoplankton biomass was estimated in terms of chlorophyll in Sathiar reservoir. The chlorophyll values were high during the low water phase in the reservoir which was also the period of summer. Following the rains and increase in water depth phytoplankton biomass decreases on account of (a) dilution, (b) loss from the reservoir through the outlets and (c) settling to the bottom along with silt. The diel variations of chlorophyll showed that the peak value was reached mostly at 12 noon due to the migration of phytoplankton to the surface.  相似文献   
733.
Restriction of glucosyl-free HMC-DNA mediated by RglB is alleviated inrecBC sbcA strains ofEscherichia coli K12. Mutation in the unlinkedrra gene reverses thisrecBC sbcA-mediated alleviation. The map position ofrra is 90.16 min on the standard map, and therra + gene product counteracts Rgl restriction. The activation of therra gene is controlled by thesbcA gene, and this regulation does not seem to require the involvement of other gene functions.  相似文献   
734.
735.

Background  

Despite great advances in clinical oncology, the molecular mechanisms underlying the failure of chemotherapeutic intervention in treating lymphoproliferative and related disorders are not well understood.  相似文献   
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738.
Serine/threonine protein kinases (STPK) play a major role in the physiology and pathogenesis of Mycobacterium tuberculosis. Here, we have examined the role of pknE, a STPK in the adaptive responses of M. tuberculosis using a deletion mutant ΔpknE. The survival of ΔpknE was assessed in the presence of stress (pH, surfactant and cell wall–damaging agents) and anti-tuberculosis drugs. ΔpknE had a defective growth in pH 7.0 and lysozyme (a cell wall–damaging agent) with better survival in pH 5.5, SDS and kanamycin (a second-line anti-tuberculosis drug). Furthermore, ΔpknE was reduced in cell size during growth in liquid media and exhibited hypervirulence in a guinea pig model of infection. In conclusion, our data suggest that pknE plays a role in adaptive response of M. tuberculosis regulating cellular integrity and survival.  相似文献   
739.
This study deals with the length-weight relationships (LWRs) of three commercially important marine fishes belonging to the family Clupeidae from the major landing centers in Tuticorin, Mandapam, Thondi, Nagapattinam and Chennai in southeast coast of India. Monthly sampling were done at the respected landing centers from June, 2018 to April, 2019 from the commercial trawlers (with cod-end mesh size of 25–35 mm) and gill netters (with different mesh size vary from 20 to 170 mm). The estimated ‘b’ values ranged from 3.1215 (Sardinella albella) to 3.1819 (Amblygaster clupeoides) and ‘a’ values varied from 0.0059 (A. clupeoides) to 0.0074 (S. albella). The study also provides a new maximum total length (TLmax) for two species A. clupeoides and Sardinella fimbriata.  相似文献   
740.
Journal of Plant Biochemistry and Biotechnology - Plant protease inhibitors are defense molecules against pests, predators and pathogens. We purified and characterized a new 14 kDa...  相似文献   
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