283 research outputs found

    Are Tier-one contractors making their money out of wasteful procurement arrangements?

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    The UK Government challenged construction to achieve 50% faster delivery and a 33% reduction of clients' capital costs by 2025 – prevailing business models won't meet these targets. Eliminating waste from construction design and delivery as advocated by lean ideals is therefore a necessary step towards these goals. However, waste understood simply as the improvement of current processes rather than fundamental system redesign will not be enough. Obtaining a better understanding and conceptualisation of waste in construction is therefore becoming more crucial. One aspect of this is to challenge the apparent coherence of prevailing procurement practices generated by the institutional, organisational, and commercial environments that surround the design and delivery of construction projects. This paper contributes to this by examining Tier 1 contractors and presents examples of practices that open debate on how to challenge prevailing procurement models for construction. Through literature review and interviews, the study discusses the factors influencing the ‘Principal-Agent’ relationship demonstrating how procurement arrangements often mirror institutional forces. These forces do not necessarily guarantee better value services, they are more likely to serve the interests of large industry players with the bargaining power to create new rules (North, 1994). A radically different delivery model, where the client intends to eliminate the management fees and confrontational behaviours of their Tier 1 contractors is described

    Anterior Urethral Advancement in Repair of Hypospadias: A Modification of the Technique

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    Background/Purpose: Anterior Urethral advancement as one stage technique for hypospadias repair was first described by Ti – Shang Cheng in 1984. It was used for repair of distal and midpenile hypospadias. It was also used for treating secondary cases and urethral fistulae. Stricture, fistulae and ventral curvature were among the complications that faced surgeons on applying the original technique. Materials & Methods: In the period between March1997 and December 2008,140 patients with distal penile hypospadias or anterior urethral fistula were treated with anterior urethral advancement technique with certain modifications. Results: The usual complications of the technique (ventral curvature of the penis, urethral fistula and meatal stenosis) were avoided. Conclusion: This study represents certain modifications that helped to a great extent in improving the results and prevented stricture and fistula formation. Index Word: Hypospadias, fistula, urethral advancemen

    Reviewing Social Life in Eastern Jordan through Burckhardts Tour in 1812 AD

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    Historical travel books are important and rich sources of information, as they describe the different aspects of life in a specific geographical area and within a specific time. One of these crucial travel books is Johann Ludwig Burckhardts Travels in Syria and the Holy Land. He recorded, through his travels in southern Syria, important details of life in the east of Jordan region at the beginning of the nineteenth century. He shed light on an important period in the history of the region, and succeeded, through the strength and accuracy of his observation, in covering rich information about social elements in the region, including values, customs, traditions, lifestyles, clothing, and food. The importance of this travel comes as a crucial source for the student of the history of East Jordan at the beginning of the nineteenth century. Indeed, it presents useful, varied, and rich information in a period characterized by scarcity of information and writings. One of the most important results of Burckhardt’s travel was the rediscovery of the Arab capital of the Nabataeans, Petra, in 1812 AD. The study also concluded that a large number of urban centers retained their names. Another important outcome of this study is that there is clear evidence that life returned to many previously deserted areas. The study also showed that the region did not witness any interest from the Ottomans in terms of education and culture since there was no mention of any school or newspaper in the region rather, the Ottomans focused only administratively on the southern region because of the pilgrimage route

    A Study on Surface Modification of Al7075-T6 Alloy against Fretting Fatigue Phenomenon

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    Aircraft engines, fuselage, automobile parts, and energy saving strategies in general have promoted the interest and research in the field of lightweight materials, typically on alloys based on aluminum. Aluminum alloy itself does not have suitable wear resistance; therefore, it is necessary to enhance surface properties for practical applications, particularly when aluminum is in contact with other parts. Fretting fatigue phenomenon occurs when two surfaces are in contact with each other and one or both parts are subjected to cyclic load. Fretting drastically decreases the fatigue life of materials. Therefore, investigating the fretting fatigue life of materials is an important subject. Applying surface modification methods is anticipated to be a supreme solution to gradually decreasing fretting damage. In this paper, the authors would like to review methods employed so far to diminish the effect of fretting on the fatigue life of Al7075-T6 alloy. The methods include deep rolling, shot peening, laser shock peening, and thin film hard coatings. The surface coatings techniques are comprising physical vapor deposition (PVD), hard anodizing, ion-beam-enhanced deposition (IBED), and nitriding

    Death associated protein kinase-1 gene methylation pattern in some leukemic patients attending Zagazig University hospitals: is it a clue?

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    Background: Leukemia is a type of cancer arising from white blood cells (WBCs) and resulting from malignant transformation of different types of white blood cell precursors. The objective was to study the DAPK-1 gene methylation pattern in leukemic patients and to through some light on its possible role as a risk factor for leukemia.Methods: Forty-one patients diagnosed as leukemic patients and 41 age-matched healthy unrelated volunteers taken as a control group. The analysis of aberrant promoter DAPK1 gene methylation was done by specific polymerase chain reaction.Results: The results of the present study showed that there was a significant association of methylated DAPK-1 promoter area among leukemic group than in control group Chi-square (X2) was 21.98, or value patients was 10.46 and there was a significant association when compared with the control group (p <0.001). And there was no significant association when compared according to gender Chi-square (X2) was 0.43 and (p=0.51). Our results revealed in the AML group DAPK-1 promoter area were methylated with percentage of 73.9%. or value for AML patients was 13.76 and there was a significant association when compared with the control group (p <0.001), in the ALL group 4 patients had methylated DAPK-1 promoter area with percentage of 57.1% or value for all patients was 6.47 and there was a significant association when compared with the control group (p=0.03) and in the CLL group 7 patients had methylated DAPK-1 promoter area with percentage of 63.6%. OR value for CCL patients was 8.5 and there was a significant association when compared with the control group (p=0.004). On the contrary, we didn’t observe any significant associations between DAPK-1 promoter area methylation and the type of leukemia (p = 0.65).Conclusions: These results suggested that DAPK1 promoter methylation might play a significant role in the pathogenesis of different types of leukemia. And the DAPK1 promoter methylation has a predictive value in the prediction of leukemia occurrence.

    Contractual governance as a source of institutionalised waste in construction: a review, implications, and road map for future research directions

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    Purpose – The construction industry has been subject to substantial criticism for its short term "hit-and-run" relationships which are focused on win-lose situations. Despite the wide recognition of these problems the industry persistently resists the radical demanded of it. Therefore, the main purposes of this study are twofold. First, to investigate why this might be the case by reviewing the governance problem confronting clients and decision makers in construction procurement, as conceptualised in Transaction Cost Economics (TCE). Secondly, to critically analyse and question the efficiency and effectiveness of various safeguarding approaches, which are taken for granted and commonly practiced in construction, from a lean perspective. Design/methodology/approach – The analysis of this paper is based on an in-depth critical review of 76 construction procurement and contractual related articles, ranging from 1994 to 2016, using theories of Lean Construction and Transaction Cost Economics as an analytical lens. Findings – Findings reveal that clients and decision makers often tend to safeguard their project-specific assets, against opportunism and exploitation, through the deployment of formal contractual arrangements and governance structures. These arrangements and structures typically dominate the management of the project delivery often to the detriment of the project itself; but because there is a belief that interests are safeguarded, clients and decision makers feel they have taken the best course of action. This goes a long way to explaining the coherence of the current construction model. Research implications – To the best of the authors' knowledge, this paper is the first to demonstrate the usefulness of using principles of Lean construction in association with TCE when analysing construction-procurement related issues. In particular, the use of a 'lean' lens helps to expose the impact of procurement governance arrangements on process flow. The study also provides a potential research agenda that can lead to the development of prescriptive conceptual frameworks for causal analysis of institutionalised waste in construction. Practical implications – The paper attempts to expose to clients and decision makers the amount of waste (and unnecessary cost) they embed by adhering to prevailing unfit-for-purpose contractual governance approaches. It also helps decision makers to consider alternative procurement arrangements and organisational techniques that could be of value and support collaborative ways of working. Originality/value – The study contributes to the overall understanding of waste in construction by providing insight into various imperfect procurement and contractual arrangements, which are taken-for-granted and impede efficiency and improvement efforts in construction. The findings presented provide a theoretical anchor and rationale for developing alternative approaches to the design and delivery of capital projects

    Berberine Reduces Neurotoxicity Related to Nonalcoholic Steatohepatitis in Rats

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    Berberine is a plant alkaloid that has several pharmacological effects such as antioxidant, antilipidemic, and anti-inflammatory effects. Nonalcoholic steatohepatitis (NASH) triggers different aspects of disorders such as impaired endogenous lipid metabolism, hypercholesterolemia, oxidative stress, and neurotoxicity. In this study, we examined the mechanism by which NASH induces neurotoxicity and the protective effect of berberine against both NASH and its associated neurotoxicity. NASH induced rats showed significant impairments in lipid metabolism with increased serum triglycerides, cholesterol, and low-density lipoprotein (LDL). The NASH induced group also demonstrated a significant oxidative stress which is characterized by increased TBARs level and decreased antioxidant capacity such as GSH and SOD levels. Moreover, the NASH induction was associated with inflammation which was demonstrated by increased TNFα and nitric oxide levels. Hyperglycemia and hyperinsulinemia were observed in the NASH induced group. Also, our results showed a significant increase in the expression of the acetylcholine esterase (AChE) and amyloid beta precursor protein (AβPP). These changes were significantly correlated with decreased insulin degrading enzyme (IDE) and beta-amyloid40 (Aβ40) and increased beta-amyloid42 (Aβ42) in the hippocampal region. Daily administration of berberine (50 mg/kg) for three weeks ameliorated oxidative stress, inflammation, hyperlipidemia, hyperglycemia, hyperinsulinemia, and the observed neurotoxicity

    The Role of Structural Flexibility in Plasmon Driven Coupling Reactions Kinetic Limitations in the Dimerization of Nitro Benzenes

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    Abstract The plasmon-driven dimerization of 4-nitrothiophenol (4NTP) to 4-4′-dimercaptoazobenzene (DMAB) is a testbed for understanding bimolecular photoreactions enhanced by nanoscale metals, in particular, regarding the relevance of electron transfer and heat transfer from the metal to the molecule. By adding a methylene group between the thiol bond and the nitrophenyl, structural flexibility is added to the reactant molecule. Time-resolved surface-enhanced Raman-spectroscopy proves that this (4-nitrobenzyl)mercaptan (4NBM) molecule has a larger dimerization rate and dimerization yield than 4NTP and higher selectivity toward dimerization. X-ray photoelectron spectroscopy and density functional theory calculations show that the electron transfer prefers activation of 4NTP over 4NBM. It is concluded that the rate limiting step of this plasmonic reaction is the dimerization step, which is dramatically enhanced by the additional flexibility of the reactant. This study may serve as an example for using nanoscale metals to simultaneously provide charge carriers for bond activation and localized heat for driving bimolecular reaction steps. The molecular structure of reactants can be tuned to control the reaction kinetics
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