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61.
62.
Cell formation consists in organizing a plant as a set of cells, each of them containing machines that process similar types or families of parts. The idea is to minimize the part flow among cells in order to reduce costs and increase productivity. The literature presents different approaches devoted to solve this problem, which are mainly based on mathematical programming and on evolutionary computing. Mathematical programming can guarantee a global optimal solution, however at a higher computational cost than an evolutionary algorithm, which can assure a good enough optimum in a fixed amount of time. In this paper, we model and solve this problem by using state-of-the-art constraint programming (CP) techniques and Boolean satisfiability (SAT) technology. We present different experimental results that demonstrate the efficiency of the proposed optimization models. Indeed, CP and SAT implementations are able to reach the global optima in all tested instances and in competitive runtime.  相似文献   
63.
Quantifying evapotranspiration (ET) from agricultural fields is important for field water management, water resources planning, and water regulation. Traditionally, ET from agricultural fields has been estimated by multiplying the weather-based reference ET by crop coefficients (Kc) determined according to the crop type and the crop growth stage. Recent development of satellite remote sensing ET models has enabled us to estimate ET and Kc for large populations of fields. This study evaluated the distribution of Kc over space and time for a large number of individual fields by crop type using ET maps created by a satellite based energy balance (EB) model. Variation of Kc curves was found to be substantially larger than that for the normalized difference vegetation index because of the impacts of random wetting events on Kc, especially during initial and development growth stages. Two traditional Kc curves that are widely used in Idaho for crop management and water rights regulation were compared against the satellite-derived Kc curves. Simple adjustment of the traditional Kc curves by shifting dates for emergence, effective full cover, and termination enabled the traditional curves to better fit Kc curves as determined by the EB model. Applicability of the presented techniques in humid regions having higher chances of cloudy dates was discussed.  相似文献   
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65.
The anti-metastatic effect of Z-100, an immunomodulatory arabinomannan extracted from Mycobacterium tuberculosis, was investigated in mice bearing B16 melanoma cells. Treatment of BF10 mice implanted with high metastatic B16F10 melanoma cells with a 10 mg/kg dose of Z-100 resulted in the reduction of experimental pulmonary metastasis as compared with that of BF10 mice treated with saline. The number of pulmonary metastatic colonies in BF1 mice (mice implanted with low metastatic B16F1 melanoma cells) was greatly increased after the inoculation of CD4+ CD11b+ CD281+ TCR alphabeta+ type 2 T cells (F10-Th2 cells) derived from BF10 mice, while only a few metastatic colonies were demonstrated in lungs of BF1 mice inoculated with naive CD4+ T cells. However, the numbers of metastatic colonies in BF1 mice were not increased when they were inoculated with the F10-Th2 cell fraction derived from Z-100-treated BF10 mice and the generation of F10-Th2 cells in BF10 mice was effectively suppressed by the Z-100 treatment. These results suggest that Z-100 inhibits pulmonary metastasis of B16 melanoma through the regulation of tumor-associated Th2 cells, which are a key cell in the acceleration of tumor metastasis.  相似文献   
66.
Mantle cell lymphoma (MCL) is molecularly characterized by bcl-1 rearrangement and cyclin D1 gene overexpression. Some aggressive variants of MCL have been described with blastic or large cell morphology, higher proliferative activity, and shorter survival. The cyclin-dependent kinase inhibitors (CDKIs) p21Waf1 and p16INK4a have been suggested as candidates for tumor-suppressor genes. To determine the role of p21Waf1 and p16INK4a gene alterations in MCLs, we examined the expression, deletions, and mutations of these genes in a series of 24 MCLs, 18 typical, and 6 aggressive variants. Loss of expression and/or deletions of p21Waf1 and p16INK4a genes were detected in 4 (67%) aggressive MCLs but in none of the typical variants. Two aggressive MCLs showed a loss of p16INK4a expression. These cases showed homozygous deletions of p16INK4a gene by Southern blot analysis. An additional aggressive MCL in which expression could not be examined showed a hemizygous 9p12 deletion. Loss of p21Waf1 expression at both protein and mRNA levels was detected in an additional aggressive MCL. No p21Waf1 gene deletions or mutations were found in this case. The p21Waf1 expression in MCLs was independent of p53 mutations. The two cases with p53 mutations showed p21Waf1 and p16INK4a expression whereas the 4 aggressive MCLs with p16INK4a and p21Waf1 gene alterations had a wild-type p53. p21Waf1 and p16INK4a were expressed at mRNA and protein levels in all typical MCLs examined. No gene deletions or point mutations were found in typical variants. Two typical MCLs showed an anomalous single-stranded conformation polymorphism corresponding to the known polymorphisms at codon 148 of p16INK4a gene and codon 31 of p21Waf1 gene. These findings indicate that p21Waf1 and p16INK4a alterations are rare in typical MCLs but the loss of p21Waf1 and p16INK4a expression, and deletions of p16INK4a gene are associated with aggressive variants of MCLs, and they occur in a subset of tumors with a wild-type p53 gene.  相似文献   
67.
This paper presents the theoretical support and experimental results of the application of advanced and intelligent control techniques to the drive control and trajectory tracking systems on a robotic wheelchair. The adaptive optimal control of the differential drive helps to improve the automatic guidance system's safety and comfort taking into consideration operating conditions such as load and distribution changes or motion actuator limitations. Furthermore, the incorporation of an optimal controller to minimize location errors and a fuzzy controller to adapt the linear velocity to the characteristics of the trajectory, provide the vehicle with a high degree of intelligence and autonomy, even when faced with obstacles. The global control solution implemented increases the features of the wheelchair for handicapped people, especially for those with a high degree of disability.  相似文献   
68.
Brain stroke is a highly prevalent pathology and a main cause of disability among older adults. If not promptly treated with recanalization therapies, primary and secondary mechanisms of injury contribute to an increase in the lesion, enhancing neurological deficits. Targeting excitotoxicity and oxidative stress are very promising approaches, but only a few compounds have reached the clinic with relatively good positive outcomes. The exploration of novel targets might overcome the lack of clinical translation of previous efficient preclinical neuroprotective treatments. In this study, we examined the neuroprotective properties of 2-aminoethoxydiphenyl borate (2-APB), a molecule that interferes with intracellular calcium dynamics by the antagonization of several channels and receptors. In a permanent model of cerebral ischemia, we showed that 2-APB reduces the extent of the damage and preserves the functionality of the cortical territory, as evaluated by somatosensory evoked potentials (SSEPs). While in this permanent ischemia model, the neuroprotective effect exerted by the antioxidant scavenger cholesteronitrone F2 was associated with a reduction in reactive oxygen species (ROS) and better neuronal survival in the penumbra, 2-APB did not modify the inflammatory response or decrease the content of ROS and was mostly associated with a shortening of peri-infarct depolarizations, which translated into better cerebral blood perfusion in the penumbra. Our study highlights the potential of 2-APB to target spreading depolarization events and their associated inverse hemodynamic changes, which mainly contribute to extension of the area of lesion in cerebrovascular pathologies.  相似文献   
69.
<正>和其他运营商相比,电信运营商向5G的过渡要更具挑战性。而通过拥抱云技术,电信运营商能够更好地克服5G技术带来的挑战,包括解决复杂的网络编排,整合新技术、应用和运营模式,开发运行新网络技能组合等。电信运营商正面临着多重挑战:一方面,他们必须开发更多的智能网络(包括边缘计算功能)以应对物联网(IoT)设备数量的快速增长,并研究如何确保5G的投资回报;另一方面,他们还需要应对新冠肺炎疫情造成的财务影响,  相似文献   
70.
This article presents baseline data from 1120 employees across 10 worksites enrolled in a workplace physical activity intervention. The study provides new data on physical activity, sedentary behaviour, and health and highlights gender, geographical, job type and industrial sector differences. Sitting at work accounted for more than 60% of participants’ total daily sitting time on work days. Weekly and monthly hours worked, body mass index (BMI) and waist circumference were significantly higher for workers in the private sector compared to the public sector. Employees in sales and customer services had significantly higher BMI scores and significantly lower scores for workability index (WAI), job satisfaction, organisational commitment and job motivation, compared to other groups. This study provides further evidence that work is a major contributor to sedentary behaviour and supports the pressing need for interventions particularly targeting private sector industries and sales and customer service sectors.

Practitioner Summary: Work accounts for more than 60% of the daily sitting time. Private sector employees had higher BMIs than those in the public sector and employees in sales and customer services had higher BMIs and poorer health compared to other occupations, suggesting that these groups should be targeted in workplace interventions.  相似文献   

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