86 research outputs found

    An Evaluation of the Applications of Quantitative Techniques (QTs) to Production Planning and Control in Manufacturing Industries

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    This study examined the factors that affect applications of Quantitative Techniques (QTs) to production planning and control in selected Nigerian manufacturing industries. Data were collected using questionnaire administered on 160 staff of 20 companies randomly chosen from each of the 8 purposively selected Nigerian Small-Scale Industries. Analysis of data was done descriptively and quantitatively using cross tabulations, percentages and inferential statistical tools respectively. Specifically, student t test was used to test the significance of the number of companies that apply QTs, The results showed that the types of QTs commonly in use include: Graphical and Charting Techniques, Control Charts, Forecasting Techniques (Simple Regression and Time Series Analyses), Inventory Model, Range, Variance and Standard Deviation, Capacity Utilization Model, and Acceptance Sampling. Control Charts topped the list with 14 (35 %). Also, 40 companies (25 %) of the 160 surveyed actually apply QTs. This number was significant at 0.05 level with t= 8.819. Metal Works industry led others in the applications of QTs with 8 (40 %) of the 20 companies surveyed in each selected industry; it also recorded 8 (20 %) of the 40 companies from all the selected industries. The study concluded that certain QTs are being applied to production planning and control by a significant number of companies from the selected Nigerian small-scale industries. Lack of adequate financial resources was the most important of all the assessed factors. Keywords: Product planning and control, Operations research models, resources utilization decision makin

    PEG Branched Polymer for Functionalization of Nanomaterials with Ultralong Blood Circulation

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    Nanomaterials have been actively pursued for biological and medical applications in recent years. Here, we report the synthesis of several new poly(ethylene glycol) grafted branched-polymers for functionalization of various nanomaterials including carbon nanotubes, gold nanoparticles (NP) and gold nanorods (NRs), affording high aqueous solubility and stability for these materials. We synthesize different surfactant polymers based upon poly-(g-glutamic acid) (gPGA) and poly(maleic anhydride-alt-1-octadecene) (PMHC18). We use the abundant free carboxylic acid groups of gPGA for attaching lipophilic species such as pyrene or phospholipid, which bind to nanomaterials via robust physisorption. Additionally, the remaining carboxylic acids on gPGA or the amine-reactive anhydrides of PMHC18 are then PEGylated, providing extended hydrophilic groups, affording polymeric amphiphiles. We show that single-walled carbon nanotubes (SWNTs), Au NPs and NRs functionalized by the polymers exhibit high stability in aqueous solutions at different pHs, at elevated temperatures and in serum. Morever, the polymer-coated SWNTs exhibit remarkably long blood circulation (t1/2 22.1 h) upon intravenous injection into mice, far exceeding the previous record of 5.4 h. The ultra-long blood circulation time suggests greatly delayed clearance of nanomaterials by the reticuloendothelial system (RES) of mice, a highly desired property for in vivo applications of nanomaterials, including imaging and drug delivery

    Intracellular SERS nanoprobes for distinction of different neuronal cell types.

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    Distinction between closely related and morphologically similar cells is difficult by conventional methods especially without labeling. Using nuclear-targeted gold nanoparticles (AuNPs) as intracellular probes we demonstrate the ability to distinguish between progenitor and differentiated cell types in a human neuroblastoma cell line using surface-enhanced Raman spectroscopy (SERS). SERS spectra from the whole cell area as well as only the nucleus were analyzed using principal component analysis that allowed unambiguous distinction of the different cell types. SERS spectra from the nuclear region showed the developments during cellular differentiation by identifying an increase in DNA/RNA ratio and proteins transcribed. Our approach using nuclear-targeted AuNPs and SERS imaging provides label-free and noninvasive characterization that can play a vital role in identifying cell types in biomedical stem cell research

    Probing the Behaviors of Gold Nanorods in Metastatic Breast Cancer Cells Based on UV-vis-NIR Absorption Spectroscopy

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    In this work, behaviors of positively-charged AuNRs in a highly metastatic tumor cell line MDA-MB-231 are examined based on UV-vis-NIR absorption spectroscopy in combination with inductively coupled plasma mass spectrometry (ICP-MS), transmission electron microscopy (TEM) and dark-field microscopic observation. It is found that characteristic surface plasmon resonance (SPR) peaks of AuNRs can be detected using spectroscopic method within living cells that have taken up AuNRs. The peak area of transverse SPR band is shown to be proportionally related to the amount of AuNRs in the cells determined with ICP-MS, which suggests a facile and real time quantification method for AuNRs in living cells. The shape of longitudinal SPR band in UV-vis-NIR spectrum reflects the aggregation state of AuNRs in the cells during the incubation period, which is proved by TEM and microscopic observations. Experimental results reveal that AuNRs are internalized by the cells rapidly; the accumulation, distribution and aggregation of AuNRs in the cells compartments are time and dose dependent. The established spectroscopic analysis method can not only monitor the behaviors of AuNRs in living cells but may also be helpful in choosing the optimum laser stimulation wavelength for anti-tumor thermotherapy

    Cell Nucleus-Targeting Zwitterionic Carbon Dots

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    An innovative nucleus-targeting zwitterionic carbon dot (CD) vehicle has been developed for anticancer drug delivery and optical monitoring. The zwitterionic functional groups of the CDs introduced by a simple one-step synthesis using beta-alanine as a passivating and zwitterionic ligand allow cytoplasmic uptake and subsequent nuclear translocation of the CDs. Moreover, multicolor fluorescence improves the accuracy of the CDs as an optical code. The CD-based drug delivery system constructed by non-covalent grafting of doxorubicin, exhibits superior antitumor efficacy owing to enhanced nuclear delivery in vitro and tumor accumulation in vivo, resulting in highly effective tumor growth inhibition. Since the zwitterionic CDs are highly biocompatible and effectively translocated into the nucleus, it provides a compelling solution to a multifunctional nanoparticle for substantially enhanced nuclear uptake of drugs and optical monitoring of translocation.open

    Nanotechnology in Head and Neck Cancer: The Race Is On

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    Rapid advances in the ability to produce nanoparticles of uniform size, shape, and composition have started a revolution in the sciences. Nano-sized structures herald innovative technology with a wide range of potential therapeutic and diagnostic applications. More than 1000 nanostructures have been reported, many with potential medical applications, such as metallic-, dielectric-, magnetic-, liposomal-, and carbon-based structures. Of these, noble metallic nanoparticles are generating significant interest because of their multifunctional capacity for novel methods of laboratory-based diagnostics, in vivo clinical diagnostic imaging, and therapeutic treatments. This review focuses on recent advances in the applications of nanotechnology in head and neck cancer, with special emphasis on the particularly promising plasmonic gold nanotechnology

    Legitimisation strategies and managerial capture: a critical discourse analysis of employment relations in Nigeria

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    YesIrrespective of the fundamental role of legitimacy in industrial relations as well as social and organisational life, little is known of the subtle meaning-making strategies through which organisational concepts, such as employment relations and engagement, are legitimised in modern world of work, particularly in developing countries such as Nigeria, which results in managerial capture. As a result, this paper explores the discursive legitimisation strategies used when making sense of employment relations in Nigeria’s conflictual, non-participatory employment relations terrain. Relying on Leeuwen’s (1995) legitimisation strategies, critical discourse analysis (CDA) and call by Bailey, Luck & Townsend (2009) and Legge (1995) to widen employment relations discourse, we explore interview, focus group and shadow report data, and distinguish and analyse five legitimisation strategies. The strategies include authorisation, moralisation, mythopoesis, rationalisation, and management. Therefore, we contend that while these specific legitimisation strategies appear in separate data source, their recurrent manifestation and application underscores legitimising discourse of managerial capture in Nigeria’s employment relations

    Development of M-learning Application based on Knowledge Management Processes

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    The wide spectrum use of mobile devices has brought numerous opportunities to develop and design Mobile Learning (M-learning) applications that will assist learners in their studies. From the M-learning perspective, in order to improve the learners' capabilities through the use of mobile devices, Knowledge Management (KM) processes (Knowledge Acquisition, Knowledge Sharing, Knowledge Application, and Knowledge Protection) should be incorporated in M-learning applications. The literature shows that several research studies were carried out with the aim of developing M-learning applications. Due to the lack of literature on examining the impact of KM processes on M-learning acceptance theoretically and practically, the main objective of this study is to develop a M-learning application that enables KM processes (Acquisition, Sharing, Application, and Protection). Moreover, the paper describes the M-learning application framework that was developed based on KM processes. In addition, the paper deliberates the implementation of the application in two different universities in two different regions, namely: Universiti Malaysia Pahang (UMP) in Malaysia, and Al Buraimi University College (BUC) in Oman. Other implications and discussions are also presented in the paper
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