173 resultados para Chain stores


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The change of supply chain relationships from the traditional adversarial to the collaborative has been increasing in the UK construction industry. To reflect this change, some attempts have been made to establish models for measuring and improving supply chain relationships in construction. However, there are obvious deficiencies in these existing models. This highlights the need for a systematic model for the assessment of construction supply chain relationships. Based on a review of the literature and an expert group discussion, an assessment framework is developed in this paper, which consists of assessment criteria, relationship levels, detailed descriptions, assessment classes and assessment procedures. The proposed framework is evaluated through expert interviews and case studies. This framework provides a roadmap for the improvement of supply chain relationships. It can help construction organisations to position their current relationship and identify key areas for relationship improvement in the future.

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PURPOSE: To investigate the effects of arginine vasopressin (AVP) on Ca(2+) sparks and oscillations and on sarcoplasmic reticulum (SR) Ca(2+) content in retinal arteriolar myocytes. METHODS: Fluo-4-loaded smooth muscle in intact segments of freshly isolated porcine retinal arteriole was imaged by confocal laser microscopy. SR Ca(2+) store content was assessed by recording caffeine-induced Ca(2+) transients with microfluorimetry and fura-2. RESULTS: The frequencies of Ca(2+) sparks and oscillations were increased both during exposure to, and 10 minutes after washout of AVP (10 nM). Caffeine transients were increased in amplitude 10 and 90 minutes after a 3-minute application of AVP. Both AVP-induced Ca(2+) transients and the enhancement of caffeine responses after AVP washout were inhibited by SR 49059, a V(1a) receptor blocker. Forskolin, an activator of adenylyl cyclase, also persistently enhanced caffeine transients. Rp-8-HA-cAMPS, a membrane-permeant PKA inhibitor, prevented enhancement of caffeine transients by both AVP and forskolin. Forskolin, but not AVP, produced a reversible, Rp-8-HA-cAMPS insensitive reduction in basal [Ca(2+)](i). CONCLUSIONS: AVP activates a cAMP/PKA-dependent pathway via V(1a) receptors in retinal arteriolar smooth muscle. This effect persistently increases SR Ca(2+) loading, upregulating Ca(2+) sparks and oscillations, and may favor prolonged agonist activity despite receptor desensitization.

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N-(3-Halogenopropyl)-4-phenylazetidin-2-ones undergo amination in liquid ammonia followed by transamidative ring expansion to give the eight-membered 4-phenyl -1,5-diazacyclooctan-2-one in excellent yield. Ring expansion of the amines in liquid ammonia is found to be much more effective than in hydrocarbon solvents. Formation of 7-, 8-, and 9-membered azalactams from the requisite -halogenoalkyl--lactams is an excellent synthetic process, though it is not applicable to 10membered rings. In the cases of rings of 13-, 15- and 17-members, although amination and apparent expansion takes place, the large rings appear not to be stable to ammonia and the final products are acyclic amides. N-[4-Halogenobut-2(Z)-enyl]-4-phenylazetidin-2-one satisfactorily forms a 9-membered (Z)-olefinic azalactam, but the (E)-isomer gives an acyclic amino amide. By using alkyl-substituted -lactam side-chains, C-substituted medium rings can be obtained; the relative instability of N-acyl -lactams to ammonia, however, leads to acylamino amides rather than expanded rings.Employing ethylamine in place of ammonia, it is shown that N-ethylated azalactams are formed satisfactorily, and using allylamine, N-allyl medium rings capable of further elaboration are obtained. The chemistry of these systems is discussed. Using transamidation in liquid ammonia, a short synthesis of the 9-membered spermidine alkaloid (±)-dihydroperiphylline is reported. Synthesis of key intermediates, whose transformation into the 13-membered alkaloids of the celabenzine group has already been effected, has been carried out.X-Ray single-crystal structure determinations for 4-phenyl-1,5-diazacyclononan-2-one, trans-4-phenyl-8-methyl-1,5-diazacyclooctan-2-one and (Z)-4-phenyl-1,5-diazacyclonon-7-en-2-one are reported, and comment is made on certain conformational features.

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This study explores the special characteristics of the construction industry and develops a maturity model for measuring and improving the relationships between the key players of a construction supply chain. The model adopts the capability maturity methodology and defines four maturity levels of construction supply chain relationships. It is in a matrix format, consisting of 24 assessment criteria in eight categories at each maturity level. It also provides three different ways of using the model. The model is evaluated through a series of expert interviews. A case study is also presented to demonstrate the application of this model in practice.

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Purpose – The purpose of this study is to explore the formative development of construction supply chain guidelines or proposals in a UK region’s schools’ estates procurement process to more effectively address a forthcoming increase in investment.

Design/methodology/approach – The research approach is interpretive. Using an action research approach, repeated semi-structured interviews and focus groups with a range of stakeholders are conducted.

Findings – The current construction supply chain in schools’ estate procurement has many difficulties, not least given the highly fragmented and disconnected nature of the projects. Synergies are being missed and there is little or no continuous improvement. Drawing on these findings, the research iteratively develops a range of proposals and guidelines to address this situation.

Research limitations/implications – This research adds weight to the current focus on pressing for change in the construction industry. It presents potentially valuable insights into the benefits of partnering arrangements and how these might usefully be incorporated into schools’ estate supply chain.

Practical implications – A set of guidelines is developed to guide the public procurement of schools’ estate in a UK region. These guidelines are set within the context of the Modernising and Rethinking Construction agenda.

Originality/value – The action research approach enabled the researchers to gain a unique insight into how public procurement and contractor personnel interact and to establish effective practical guidelines.

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Cholecystokinin (CCK) is a peptide hormone secreted from the I-cells of the intestine and it has important physiological actions related to appetite regulation and satiety. In this study we used STC-1 cells to investigate the effects of common dietary-derived fatty acids (FAs) on I-cell secretory function and metabolism. We extend earlier studies by measuring the acute and chronic effects of 11 FAs on CCK secretion, cellular CCK content, CCK mRNA levels, cellular DNA synthesis, cellular viability and cytotoxicity. FAs were selected in order to assess the importance of chain length, degree of saturation, and double bond position and conformation. The results demonstrate that secretory responses elicited by dietary FAs are highly selective. For example, altering the conformation of a double bond from cis to trans (i.e. oleic acid versus elaidic acid) completely abolishes CCK secretion. Lauric acid appears to adversely affect I-cell metabolism and arachidonic acid suppresses DNA synthesis. Our studies reveal for the first time that conjugated linoleic acid isoforms are particularly potent CCK secretagogues, which also boost intracellular stores of CCK. These actions of conjugated linoleic acid may explain satiating actions observed in dietary intervention studies.

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Background: Doxorubicin is one of the most effective anti-cancer drugs but its use is limited by cumulative cardiotoxicity that restricts lifetime dose. Redox damage is one of the most accepted mechanisms of toxicity, but not fully substantiated. Moreover doxorubicin is not an efficient redox cycling compound due to its low redox potential. Here we used genomic and chemical systems approaches in vivo to investigate the mechanisms of doxorubicin cardiotoxicity, and specifically test the hypothesis of redox cycling mediated cardiotoxicity.

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The increasing risks and costs of new product development require firms to collaborate with their supply chain partners in product management. In this paper, a supply chain model is proposed with one risk-neutral supplier and one risk-averse manufacturer. The manufacturer has an opportunity to enhance demand by developing a new product, but both the actual demand for new product and the supplier’s wholesale price are uncertain. The supplier has an incentive to share risks of new product development via an advance commitment to wholesale price for its own profit maximization. The effects of the manufacturer’s risk sensitivity on the players’ optimal strategies are analyzed and the trade-off between innovation incentives and pricing flexibility is investigated from the perspective of the supplier. The results highlight the significant role of risk sensitivity in collaborative new product development, and it is found that the manufacturer’s innovation level and retail price are always decreasing in the risk sensitivity, and the supplier prefers commitment to wholesale price only when the risk sensitivity is below a certain threshold.