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141.
This paper describes an approach used to evaluate the performance of different supply chain configurations in customised contexts. Based on historical data collected from the supply chain of a shoe producer, different configurations are evaluated based on a discrete-event simulation by highlighting the performance of the supply chain (in terms of supply chain order lead-time and inventory volume) when the production switched from standard production (characterised by batches of large quantities of the same product) to customised production (characterised by a small of series batches with high product variability). The simulation approach relies on experimentation through executable configurations, which enables the creation of different scenarios, and is then applied to the case of an actual firm in the footwear industry. The managerial implications of these findings are discussed. 相似文献
142.
Nick Gravish Mateo Garcia Nicole Mazouchova Laura Levy Paul B. Umbanhowar Michael A. D. Goodisman Daniel I. Goldman 《Journal of the Royal Society Interface》2012,9(77):3312-3322
Social insects work together to complete tasks. However, different individuals within a colony may vary in task proficiency. We investigated if fire ant (Solenopsis invicta) worker body size influenced the ability to construct tunnels—a key component of subterranean nests. We monitored excavation by worker groups in a substrate of small wetted glass particles in quasi-two-dimensional arenas. Morphological and network features of the tunnel system were measured. Total tunnel area did not differ significantly between groups of large and small workers, although the tunnel area of control sized workers was significantly larger than that of large workers. Moreover, large workers created wider but shorter tunnels, with slower growth rate of tunnel number. However, edge–vertex scaling and degree distribution of the tunnel network were similar across all treatments. In all cases, the amount of excavated material was correlated with the number of active workers. Our study reveals that morphological features of excavated tunnels show modest variation when constructed by workers of varying sizes, but topological features associated with the tunnel network are conserved. These results suggest that important behavioural aspects of tunnel construction—and thus nest building—are similar among morphologically distinct members of fire ant societies. 相似文献
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Laura Baranello Fedor Kouzine Damian Wojtowicz Kairong Cui Teresa M. Przytycka Keji Zhao David Levens 《International journal of molecular sciences》2014,15(7):13111-13122
Genomic DNA is under constant assault by endogenous and exogenous DNA damaging agents. DNA breakage can represent a major threat to genome integrity but can also be necessary for genome function. Here we present approaches to map DNA double-strand breaks (DSBs) and single-strand breaks (SSBs) at the genome-wide scale by two methods called DSB- and SSB-Seq, respectively. We tested these methods in human colon cancer cells and validated the results using the Topoisomerase II (Top2)-poisoning agent etoposide (ETO). Our results show that the combination of ETO treatment with break-mapping techniques is a powerful method to elaborate the pattern of Top2 enzymatic activity across the genome. 相似文献
146.
Salvatore Mirabile Dr. Serena Vittorio Prof. Maria Paola Germanò Dr. Ilenia Adornato Dr. Laura Ielo Prof. Antonio Rapisarda Prof. Rosaria Gitto Francesca Pintus Dr. Antonella Fais Prof. Laura De Luca 《ChemMedChem》2021,16(19):3083-3093
There is a considerable attention for the development of inhibitors of tyrosinase (TYR) as therapeutic strategy for the treatment of hyperpigmentation disorders in humans. Continuing in our efforts to identify TYR inhibitors, we describe the design, synthesis and pharmacophore exploration of new small molecules structurally characterized by the presence of the 4-fluorobenzylpiperazine moiety as key pharmacophoric feature for the inhibition of TYR from Agaricus bisporus (AbTYR). Our investigations resulted in the discovery of the competitive inhibitor [4-(4-fluorobenzyl)piperazin-1-yl]-(3-chloro-2-nitro-phenyl)methanone 26 (IC50=0.18 μM) that proved to be ∼100-fold more active than reference compound kojic acid (IC50=17.76 μM). Notably, compound 26 exerted antimelanogenic effect on B16F10 cells in absence of cytotoxicity. Docking analysis suggested its binding mode into AbTYR and into modelled human TYR. 相似文献
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Ana Laura CIMADOR Emeli Luciana GALANTE Lucila Ibel MUÑOZ Patricia Silvia ROMANO Antonella Denisse LOSINNO María Cristina VANRELL 《Biocell》2019,43(1):13-20
Trypanosoma rangeli and T. cruzi are both parasitic unicellular species that infect humans. Unlike T. cruzi,
the causative agent of Chagas disease, T. rangeli is an infective and non-pathogenic parasite for humans, but pathogenic
for vectors from the Rhodnius genus. Because both species can coexist in different hosts and overlap their infective
cycles but very little is known about the infection of T. rangeli in mammalian cells, we decided to characterize both the
development of this parasite in cell culture and the effect of therapeutic agents with potential trypanocidal action on
it. We found that T. rangeli exhibits a cycle of infection in Vero cells similar to that for T. cruzi and that the repurposed
drug, 17-AAG, and the natural extract Artemisia sp. essential oil produce a toxic effect on epimastigotes showing
a trypanocidal action from the fifth day of culture. Both treatments also affected the infection of trypomastigotes
and reduced the capacity of replication of amastigotes of T. rangeli. Since T. cruzi / T. rangeli coinfection cases have
been reported, the finding of drugs with potential activity against both species could be significant in the future.
Furthermore, studies of susceptibility of both species to drugs could also help to know the different mechanisms of
pathogenicity in humans displayed by T. cruzi that are absent in T. rangeli 相似文献
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Laura Sanae Takeuti Jovanelli Sandra Emi Kitahara Julio Cesar Bastos Fernandes 《Sensing and Instrumentation for Food Quality and Safety》2016,10(2):336-340
We studied the parameters that may affect the analysis of the moisture content in wheat flour using infrared scales. The parameters were studied by one-factor at a time methodology and then, by full-factorial design (23). The best condition using infrared scales occurred at 120 °C, with a sample weight of 1.5 g and an exposure time to infrared radiation of 6 min. We observed the interaction effect between the three factors studied. The analysis time was 60 times lower than classical method. The optimized method for determination of the moisture content in wheat flour using infrared scales was validated to range between 9 and 17 %. 相似文献