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1.
The vehicle routing problem with deliveries and pickups is one of the main problems within reverse logistics. This paper focuses on an important assumption that divides the literature on the topic, namely the restriction that all deliveries must be completed before pickups can be made. A generalised model is presented, together with a mathematical formulation and its resolution. The latter is carried out by adopting a suitable implementation of the reactive tabu search metaheuristic. Results show that significant savings can be achieved by allowing a mixture of delivery and pickup loads on-board and yet not incurring delays and driver inconvenience.  相似文献   
2.
Rare earths(REs) play a key role in distorting spinel structure by creating some defects at the lattice sites and make them suitable for magnetodielectric applications.In the present study,the nanoferrites of CuRE_(0.02)Fe_(1.98)O_4,where REs=Y~(3+),Yb~(3+),Gd~(3+),were prepared using one step sol-gel method.The prepared samples are copper ferrite(CFO),yttrium doped copper ferrite(Y-CFO),ytterbium doped copper ferrite(Yb-CFO) and gadolinium doped copper ferrite(Gd-CFO),respectively.The single-phase structure of all the REs doped nanoferrites was determined by X-ray diffraction(XRD) analysis.The porosity,agglomerations and grain size of the REs doped copper ferrite were examined using field emission scanning electron microscopy(FESEM) analysis.Fourier transform infrared spectroscopy(FTIR)elaborates the phase formation and environmental effects on the REs doped nanoparticles(NPs).The recorded room temperature M-H loops from a vibrating sample magnetometer(VSM) elucidate the magnetic properties of the REs doped spinel nanoferrites.The magnetic saturation(M_s) was calculated in the range of 23.08 to 51.78 emu/g.The calculated coercivity values(272.6 to 705.60 Oe) confirm the soft magnetic behavior of REs doped copper ferrites.Furthermore,the electromagnetic and dielectric properties were assessed using a Vector network analyzer(VNA) from 1 to 6 GHz.The permeability,permittivity,dielectric tangent loss and electric modulus of the REs doped spinel ferrites illustrate that the prepared NPs may be suitable for microwave and high frequency applications.  相似文献   
3.
Objectives were to establish growth patterns for weight and height in dairy calves from birth to 90 d and to estimate appropriate genetic parameters. Measurements were 7943 body weights and 7005 wither heights of 752 calves. Represented over 12 yr were three breeds, 348 dams, and 115 sires; data resulted from designed calf nutrition experiments. Sources of variation considered in various least squares analyses of variance were breed, sire in breed, calf in sire in breed, sex of calf, treatment-year category, and several interactions. Repeatabilities of weights and heights between birth and 90 d were .64 and .88; heritabilities were .22 and .30; genetic and phenotypic correlations were .53 and .73. A regression equation was estimated for each calf. From these 752 equations, heritabilities of initial weight, initial height, and rates of growth in weight and height were .53, .50, .44, and .19. Genetic correlations were .81; -.07; -.05; .26; .14; .84. Selection schemes for these traits in dairy cattle should consider that although weights and heights at birth and thereafter are highly and positively correlated genetically, as are gains, birth measurements and gains to 90 d may be uncorrelated.  相似文献   
4.
The rapid progression in biomaterial nanotechnology apprehends the potential of non-toxic and potent polysaccharide delivery modules to overcome oral chemotherapeutic challenges. The present study is aimed to design, fabricate and characterize polysaccharide nanoparticles for methotrexate (MTX) delivery. The nanoparticles (NPs) were prepared by Abelmoschus esculentus mucilage (AEM) and chitosan (CS) by the modified coacervation method, followed by ultra-sonification. The NPs showed much better pharmaceutical properties with a spherical shape and smooth surface of 213.4–254.2 nm with PDI ranging between 0.279–0.485 size with entrapment efficiency varying from 42.08 ± 1.2 to 72.23 ± 2.0. The results revealed NPs to possess positive zeta potential and a low polydispersity index (PDI). The in-vitro drug release showed a sustained release of the drug up to 32 h with pH-dependence. Blank AEM -CS NPs showed no in-vivo toxicity for a time duration of 14 days, accompanied by high cytotoxic effects of optimized MTX loaded NPs against MCF-7 and MD-MBA231 cells by MTT assay. In conclusion, the findings advocated the therapeutic potential of AEM/CS NPs as an efficacious tool, offering a new perspective for pH-responsive routing of anticancer drugs with tumor cells as a target.  相似文献   
5.
Nickel ferrites with high theoretical capacitance value as compared to the other metal oxides have been applied as electrode material for energy storage devices i.e. batteries and supercapacitors. High tendency towards aggregation and less specific surface area make the metal oxides poor candidate for electrochemical applications. Therefore, the improvements in the electrochemical properties of nickel ferrites (NiFe2O4) are required. Here, we report the synthesis of graphene nano-sheets decorated with spherical copper substituted nickel ferrite nanoparticles for supercapacitors electrode fabrication. The copper substituted and unsubstituted NiFe2O4 nanoparticles were prepared via wet chemical co-precipitation route. Reduced graphene oxide (rGO) was prepared via well-known Hummer's method. After structural characterization of both ferrite (Ni1-xCuxFe2O4) nanoparticles and rGO, the ferrite particles were decorated onto the graphene sheets to obtain Ni1-xCuxFe2O4@rGO nanocomposites. The confirmation of preparation of these nanocomposites was confirmed by scanning electron microscopy (SEM). The electrochemical measurements of nanoparticles and their nanocomposites (Ni0.9Cu0.1Fe2O4@rGO) confirmed that the nanocomposites due to highly conductive nature and relatively high surface area showed better capacitive behavior as compared to bare nanoparticles. This enhanced electrochemical energy storage properties of nanocomposites were attributed to the graphene and also supported by electrical (I-V) measurements. The cyclic stability experiments results showed ~65% capacitance retention after 1000 cycles. However this retention was enhanced from 65% to 75% for the copper substituted nanoparticles (Ni0.9Cu0.1Fe2O4) and 65–85% for graphene based composites. All this data suggest that these nanoparticles and their composites can be utilized for supercapacitors electrodes fabrication.  相似文献   
6.
7.
This work is based on formulating and optimizing controlled release (CR) valsartan (160 mg) tablets using different viscosity grades of the cellulosic polymer. The objective was to develop an effective once-daily drug delivery system of this cardiovascular agent. Central composite design was used for designing the formulations. Polymers used were Methocel® K4M, K15M and K100M. Compatibility of excipients with active was studied through FT-IR. Micromeritic properties were determined and formulations exhibiting appropriate flow characteristics were compressed. Swelling behavior and in vitro buoyancy effect were studied and response surface curves were constructed to optimize the formulation. Multi-point dissolution profiles of valsartan CR tablets at pH 1.2, 4.5 and 6.8 were obtained. Model-dependent and model-independent methods were performed including f2, stability test as per ICH guidelines and ANOVA. FT-IR studies revealed the compatibility of valsartan with all excipients. Formulation K4T9 (containing 25% K4M polymer) was selected to be the best optimized trial, based on physical properties and controlled release profile (23% at 4 h, 82% at 16 h and 100% at 24 h). Results of buoyancy and swelling behavior indicated that HPMC-K4M polymer exhibited excellent floating lag time and swelling indexes. In vitro drug release kinetics showed that formulation K4T9 displayed Korsmeyer–Peppas drug release pattern with r value > 0.99. The manufacturing process of K4T9 was also found to be reproducible with a shelf life period of 41 and 36 months at room temperature and accelerated conditions, respectively. Valsartan CR matrix-based formulation was successfully prepared with Methocel K4M retardant.  相似文献   
8.
The purified crude lipid of Psoralia corylifolia seeds was subjected to lipid class and fatty acid analysis by thin layer and gas chromatography. The lipid classes identified were triacyl glycerol, free fatty acid, diacyl glycerol, mono acyl glycerol, hydrocarbon-waxester and polar lipid fractions. Most of the fractions were found to contain high level of C18:1 while C18:0, C18:3 and C20:0 were also found to be present in all the lipid fractions. It has been observed that the diacyl and monoacyl glycerol fractions contain significant amounts of C14:0 and C18:0 while the hydrocarbon-waxester fraction was rich in C22:0. The polar lipids contain high level of C18:3 and low level of C18:1 as compared to other lipid fractions. The fatty acid composition of the whole oil was also determined and found to be similar to other fractions. Unidentified long chain fatty acids were also present in significant amounts in all the lipid fractions.  相似文献   
9.
The development of an inorganic electrochemical stable solid-state electrolyte is essentially responsible for future state-of-the-art all-solid-state lithium batteries (ASSLBs). Because of their advantages in safety, working temperature, high energy density, and packaging, ASSLBs can develop an ideal energy storage system for modern electric vehicles (EVs). A solid electrolyte (SE) model must have an economical synthesis approach, exhibit electrochemical and chemical stability, high ionic conductivity, and low interfacial resistance. Owing to its highest conductivity of 17 mS·cm-1, and deformability, the sulfide-based Li7P3S11 solid electrolyte is a promising contender for the high-performance bulk type of ASSLBs. Herein, we present a current glimpse of the progress of synthetic procedures, structural aspects, and ionic conductivity improvement strategies. Structural elucidation and mechanistic approaches have been extensively discussed by using various characterization techniques. The chemical stability of Li7P3S11 could be enhanced via oxide doping, and hard and soft acid/base (HSAB) concepts are also discussed. The issues to be undertaken for designing the ideal solid electrolytes, interfacial challenges, and high energy density have been discoursed. This review aims to provide a bird's eye view of the recent development of Li7P3S11-based solid-state electrolyte applications and explore the strategies for designing new solid electrolytes with a target-oriented approach to enhance the efficiency of high energy density all-solid-state lithium batteries.  相似文献   
10.
Vincristine (VCR) is a widely used chemotherapy drug that induced peripheral painful neuropathy. Yet, it still lacks an ideal therapeutic strategy. The transient receptor potential (TRP) channels, purinergic receptor (P2Y), and mitogen-activated protein kinase (MAPK) signaling play a crucial role in the pathogenesis of neuropathic pain. Withametelin (WMT), a potential Phytosteroid isolated from datura innoxa, exhibits remarkable neuroprotective properties. The present investigation was designed to explore the effect of withametelin on VCR-induced neuropathic pain and its underlying molecular mechanism. Initially, the neuroprotective potential of WMT was confirmed against hydrogen peroxide (H2O2)-induced PC12 cells. To develop potential candidates for neuropathic pain treatment, a VCR-induced neuropathic pain model was established. Vincristine (75 μg/kg) was administered intraperitoneally (i.p.) for 10 consecutive days (day 1–10) for the induction of neuropathic pain. Gabapentin (GBP) (60 mg/kg, i.p.) and withametelin (0.1 and 1 mg/kg i.p.) treatments were given after the completion of VCR injection on the 11th day up to 21 days. The results revealed that WMT significantly reduced VCR-induced pain hypersensitivity, including mechanical allodynia, cold allodynia, and thermal hyperalgesia. It reversed the VCR-induced histopathological changes in the brain, spinal cord, and sciatic nerve. It inhibited VCR-induced changes in the biochemical composition of the myelin sheath of the sciatic nerve. It markedly downregulated the expression levels of TRPV1 (transient receptor potential vanilloid 1); TRPM8 (Transient receptor potential melastatin 8); and P2Y nociceptors and MAPKs signaling, including ERK (Extracellular Signal-Regulated Kinase), JNK (c-Jun N-terminal kinase), and p-38 in the spinal cord. It suppressed apoptosis by regulating Bax (Bcl2-associated X-protein), Bcl-2 (B-cell-lymphoma-2), and Caspase-3 expression. It considerably attenuated inflammatory cytokines, oxidative stress, and genotoxicity. This study suggests that WMT treatment suppressed vincristine-induced neuropathic pain by targeting the TRPV1/TRPM8/P2Y nociceptors and MAPK signaling.  相似文献   
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