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941.
This paper develops and tests an efficient mixed integer programming model for capacitated lot sizing and scheduling with non-triangular and sequence-dependent setup times and costs incorporating all necessary features of setup carryover and overlapping on different machine configurations. The model’s formulation is based on the asymmetric travelling salesman problem and allows multiple lots of a product within a period. The model conserves the setup state when no product is being processed over successive periods, allows starting a setup in a period and ending it in the next period, permits ending a setup in a period and starting production in the next period(s), and enforces a minimum lot size over multiple periods. This new comprehensive model thus relaxes all limitations of physical separation between the periods. The model is first developed for a single machine and then extended to other machine configurations, including parallel machines and flexible flow lines. Computational tests demonstrate the flexibility and comprehensiveness of the proposed models.  相似文献   
942.
We examined the effects of photobiomodulation (PBM) independently and combined with curcumin on stereological parameters and basic fibroblast growth factor (bFGF), hypoxia-inducible factor-1α (HIF-1α), and stromal cell-derived factor-1α (SDF-1α) gene expressions in an excisional wound model of rats with type one diabetes mellitus (T1DM). T1DM was induced by an injection of streptozotocin (STZ) in each of the 90 male Wistar rats. One round excision was generated in the skin on the back of each of the 108 rats. The rats were divided into six groups (n = 18 per group): control (diabetic), untreated group; vehicle (diabetic) group, which received sesame oil; PBM (diabetic) group; curcumin (diabetic) group; PBM + curcumin (diabetic) group; and a healthy control group. On days 4, 7, and 15, we conducted both stereological and quantitative real-time PCR (qRT-PCR) analyses. The PBM and PBM + curcumin groups had significantly better inflammatory response modulation in terms of macrophages (P < .01), neutrophils (P < .001), and increased fibroblast values compared with the other groups at day 4 (P < .001), day 7 (P < .01), and day 15 (P < .001). PBM treatment resulted in increased bFGF gene expression on days 4 (P < .001) and 7 (P < .001), and SDF-1α gene expression on day 4 (P < .001). The curcumin group had increased bFGF (P < .001) expression on day 4. Both the PBM and PBM + curcumin groups significantly increased wound healing by modulation of the inflammatory response, and increased fibroblast values and angiogenesis. The PBM group increased bFGF and SDF-1α according to stereological and gene expression analyses compared with the other groups. The PBM and PBM + curcumin groups significantly increased the skin injury repair process to more rapidly reach the proliferation phase of the wound healing in T1DM rats.  相似文献   
943.
Cobalt [(OH)2-salophen] (N,N′-bis(4-hydroxysalicylidene)phenylene-1,2-diamine) complex was covalently grafted on the chemical modification of multi-wall carbon nanotubes (MWNTs); [Co((OH)2-salophen)]@MWNTs]. The as-products were characterized by spectroscopy (FT-IR, Raman, and UV–Vis), TGA, and TEM. The cobalt(II) Schiff-base complex covalently anchored on modified MWNTs was characterized by different techniques. The catalytic activity of the novel nanotubes based materials was tested in the epoxidation of cyclohexene in the iso-butyraldehyde/air system using acetonitrile as solvent and very high conversion was obtained. The experimental results indicated very good catalytic activity and selectivity in the epoxidation of cyclohexene. Repeated runs of the catalysts were carried out three times and the results indicated that the catalyst was stable for the epoxidation of cyclohexene.  相似文献   
944.
Limb-girdle muscular dystrophies (LGMDs) are a highly heterogeneous group of neuromuscular disorders that are associated with weakness and wasting of muscles in legs and arms. Signs and symptoms may begin at any age and usually worsen by time. LGMDs are autosomal disorders with different types and their prevalence is not the same in different areas. New technologies such as next-generation sequencing can accelerate their diagnosis. Several important pathological mechanisms that are involved in the pathology of the LGMD include abnormalities in dystrophin–glycoprotein complex, the sarcomere, glycosylation of dystroglycan, vesicle and molecular trafficking, signal transduction pathways, and nuclear functions. Here, we provide a comprehensive review that integrates LGMD clinical manifestations, prevalence, and some pathological mechanisms involved in LGMDs.  相似文献   
945.
During 2011–2012, an extensive leaf spot disease caused by Stemphylium lycopersici was observed on vegetable crops including, tomato, eggplant, pepper and lettuce in major vegetable-growing regions of Malaysia. Four isolates of S. lycopersici obtained from each vegetable crop were used to determine cultural and physiological characteristics. The variations were found in colony colour (pale to light grey or light as well as the brown), texture (cottony or mycelium flat), shape (regular with concentric growth rings or irregular) and pigmentation (yellow or deep red) of the cultures. The optimum temperature for the conidial germination and mean radial growth of the isolates was 25?°C, and the radial growth of the isolates was maximal on V-8 juice agar followed by potato carrot agar. The maximum sporulation of S. lycopersici isolates was observed on V-8 juice agar media under 12/12 h light/darkness photoperiod at 25?°C.  相似文献   
946.

A set of carbon monoxide (CO) gas sensors based on porous silicon (PSi)/gold nanoparticle (AuNP) hetro structures were fabricated. Different forms of PSi surface morphologies were studied as a substrate for growth of AuNPs. Simple dipping process of PSi in hydrogen tetrachloroaurate (III) solution (HAuCl4) at fixed concentrations of 10−2 M/3.5 HF was used to synthesize AuNPs. The n-type PSi was equipped through photo-electrochemical etching process at current density value of 10 mA/cm2 under illumination condition of 530-nm wavelength and laser illumination intensity of 20 to 80 mW/cm2. Three different forms of PSi morphology, meso, macro, and double layers with pore shapes and sizes, were prepared. The structural and surface morphology properties of PSi-based substrate before and after deposition of AuNPs were investigated through studying of scanning electron microscopy (SEM), photoluminescence (PL), and X-ray diffraction (XRD). The electrical property (J-V) was carried out in primary vacuum and CO at low pressure. The results show that PSi surface morphologies strongly influenced the AuNP sizes and hence the sensor performance. It was found that decrease the AuNP sizes could be occasioned in high and fast current response.

  相似文献   
947.
Reaction of o-phenylene diamine with thiosemicarbazide did not give benzotriazine-2-thione 2 as reported, although the product was found to be benzimidazole-2-thione 3. Glycosylation of 3 with acetobromo sugars 4a-4b gave the respective thioglycosides 7a-7d in addition to minor products of the nucleosides 8a and 8b, in the case of the gluco- and galacto-analogs, respectively. The regioselectivity of glycosylation reaction has been investigated.  相似文献   
948.
The current study aims to investigate the anticancer potential of Periploca hydaspidis extracts against HCCLM3 and MDA-MB 231 cell lines with invasive properties and to identify molecular targets underlying its action mechanism. Cytotoxic screening of plant extracts was done via MTT assay against liver and breast cancer cell lines and GC/MS of the best cytotoxic fraction was performed to identify its chemical composition. Flow cytometry detected apoptosis and cell-cycle changes after drug treatment. The specified cells were studied for migration and invasion potential along with performing western blot analysis of proteins involved in apoptosis, cell-cycle, metastasis, and MAPK (Mitogen-activated protein kinase) cell-signaling pathway. The results revealed the crude methanol (PHM) fraction of P. hydaspidis shown dose and time dependent cell-proliferative inhibition response. GC/MS analysis detected 54 compounds of which fatty acids (29.8%), benzenoids (15.7%), and esters (14.3%) constituted the bulk. The inhibitory effect against cancer cells was linked with cell-cycle arrest at G0/G1 phase, induction of apoptosis, reduced migration and invasion capabilities post treatment. PHM induced apoptosis via downregulation of anti-apoptotic (survivin, B-cell lymphoma Extra-large; BCL-XL, X-linked inhibitor of apoptosis protein; XIAP, Myelocytomatosis; C-myc), metastatic (Matrix metallopeptidases 9/2; MMP9/2), and cell-cycle regulatory (cyclin D1 and E) proteins, whereas upregulation of pro-apoptotic proteins (Bcl-2 homologous antagonist/killer; BAK, Bcl-2-Associate X protein; BAX, cleaved caspases; 3,7,8,9, and PARP) and activation of MAPK (Jun amino-terminal kinase; JNK and P38) pathway. P38 was needed for PHM-induced apoptosis, where the inhibition of P38 by pharmacological inhibitor (SB239063) diminished the apoptotic effects. Overall, our results conclude that PHM can inhibit cell-proliferation and induce apoptotic effects by activation of P38 MAPK cell-signaling pathway. This suggests the methanol fraction of P. hydaspidis (PHM) to have anticancer compounds, potentially useful for treating liver and breast cancer. In future, one-step advance studies of PHM regarding its role in metastatic inhibition, immune response modulation for reducing tumor, and inducing apoptosis in suitable animal models would be an interesting and promising research area.  相似文献   
949.
950.
15-Acetyldeoxynivalenol (15-AcDON) is a low molecular weight sesquiterpenoid trichothecene mycotoxin associated with Fusarium ear rot of maize and Fusarium head blight of small grain cereals. The accumulation of mycotoxins such as deoxynivalenol (DON) and 15-AcDON within harvested grain is subject to stringent regulation as both toxins pose dietary health risks to humans and animals. These toxins inhibit peptidyltransferase activity, which in turn limits eukaryotic protein synthesis. To assess the ability of intracellular antibodies (intrabodies) to modulate mycotoxin-specific cytotoxocity, a gene encoding a camelid single domain antibody fragment (VHH) with specificity and affinity for 15-AcDON was expressed in the methylotropic yeast Pichia pastoris. Cytotoxicity and VHH immunomodulation were assessed by continuous measurement of cellular growth. At equivalent doses, 15-AcDON was significantly more toxic to wild-type P. pastoris than was DON. In turn, DON was orders of magnitude more toxic than 3-acetyldeoxynivalenol. Intracellular expression of a mycotoxin-specific VHH within P. pastoris conveyed significant (p = 0.01) resistance to 15-AcDON cytotoxicity at doses ranging from 20 to 100 μg·ml−1. We also documented a biochemical transformation of DON to 15-AcDON to account for the attenuation of DON cytotoxicity at 100 and 200 μg·ml−1. The proof of concept established within this eukaryotic system suggests that in planta VHH expression may lead to enhanced tolerance to mycotoxins and thereby limit Fusarium infection of commercial agricultural crops.  相似文献   
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