436 research outputs found

    A hybrid model of communication and information management in mega construction projects in Dubai using a new critical success factor approach

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    Mega construction projects are complex undertakings. The complexity is increased during a construction boom in a city such as Dubai where more than 80% of material and labour resources are imported. The complexities inherent in mega construction projects include uncertainty and interdependencies, which affect project management performance at the operational level where most of the problems occur. Understanding these processes, how they interrelate and how to overcome the complexities is crucial for increasing the chances of project management success. This research contributed to construction project management theory and practice by using a highly inductive exploratory qualitative approach for capturing formal and informal processes in mega construction projects in Dubai. A dynamic model depicting the complementary formal and informal processes is developed showing formal and informal processes and how they interrelate to reduce complexity. Guidelines on how and when to use specific processes are provided as a framework for the model. This framework may be used to help develop communication processes in future complex projects to increase chances of project management success. The research was conducted by exploring two case study projects fitting the characteristics of mega construction projects. Both case study projects were of values above 1.5 Billion US Dollars and were similar in scope with elements including amusement parks, retail areas, hotels, extensive infrastructure and large landscape areas. Both case study projects were of an experimental character, considered an engineering achievement, complex, and thereby, difficult to control. The research data were collected through semi-structured interviews with 83 project staff from both case study projects. Rich picture diagrams of the organization and processes were made from data collected during the interviews and case study project documents. The analysis was performed in three phases where the results from each phase were built upon cumulatively. The first phase examined what the most crucial critical success factors (CSFs) were in the case study projects. These were revealed to be communication, top management support and effective change management. In the second phase each CSF was analyzed where it was found it that the majority of important communication modes were informal and were was most effective in reducing complexity. Furthermore, it was found that the characteristics of the client were crucial in both case study projects. The third phase involved development of the dynamic hybrid model from the rich picture diagrams created showing the interplay between formal and informal processes. It was found that informal processes are ad-hoc and chaotic in nature and controlled by individuals in the project. Development of guidelines for the positive use of informal processes was required. From the analysis it was found that the characteristics of client staff and individuals in the case study projects provided the main guidelines for effective use of the hybrid model. The research provides insights into the formal and informal processes and the reduction and management of complexity inherent in mega construction projects. Current research in managing complexity is from the perspective of the formal process where the informal processes are neglected, despite research and practice indicating their importance in construction projects. The research presents a systemic dynamic model of the processes for mega construction projects revealing that formal and informal processes are required and are complementary. Guidelines for the successful use of the model provide a framework for its application in practice. This shows how it can be used to inform understanding of processes in the context of the research. The model and guidelines were validated via discussions with practitioners experienced in construction of mega projects. Future work should expand the findings to applications of the model in practice for management of complex projects. The model may be used by practitioners to act as a guide in how to manage construction processes to consciously overcome the inherent complexities to achieve project management objectives. This tool may also be used to inform clients of the inherent complexities and the level of informality required to overcome them. IT/IS practitioners may use the model and framework to understand the complexities in construction, and thereby, develop systems that are practically applied in construction projects. Researchers in the field may build upon the model and findings to increase knowledge regarding construction processes, particularly informal processes.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

    A hidden cause of infertility in hypothyroid patients

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    Methylene tetrahydrofolate reductase (MTHFR) gene mutations could be the cause of infertility in hypothyroid patients. Hence, it is worthy to screen for MTHFR gene mutations in infertile hypothyroid females and their partners if infertility persists after optimizing thyroid function

    Spatial Analysis as a Tool for Selecting the Most Suitable Sites for Rural Spatial Development Projects Case study: Agro polis Development Project for the plain of Al-Ghab

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    The spatial development of rural areas is based on the optimal investment of natural resources (environmental and human). There is a close relationship between the development processes, the place and the environment, and this relation appears in the settlement of development projects in a way that ensures continuity for future generations and the settlement of human activity. The attraction of the Al-Ghab area for development projects since the middle of the last century until now has led to the emergence and development of scattered population groups in the countryside of this plain and along its area and the large percentage of reclaimed land. It also led to high population growth rates to exceed the national population growth rates of Syria where the population growth rate for the administrative jungle region for the period between (1970-1981) value (0.047) while it was at the level of Syria (0.034). In the absence of spatial balance of the distribution of these projects and the lack of harmony with the natural and human components where it did not take into account the appropriate spatial and specificity of the region, which led to overriding the use of agricultural land and converted to residential use and the depletion of many of the resources that contain them. The aim of this research is to assess the spatial compatibility of the comprehensive development project for the plain of the Al-Ghab through a spatial analytical methodology that seeks to preserve the natural resources of agricultural lands forests and not to build at their expense, and to link the natural environment with the reflection of its effects on human activity. The spatial analysis method takes into account the economic, physical, environmental and social factors and contributes to determining the most suitable locations for the development of rural spatial development projects. تقوم التنمية المكانية الريفية على الاستثمار الأمثل للموارد الطبيعية (البيئية والبشرية) فهناك علاقة وثيقة بين عمليات التنمية والمكان والبيئة, وهذه العلاقة تظهر في توطين مشروعات التنمية بأسلوب يضمن الاستمرارية للأجيال القادمة، وتوطين النشاط البشري. وعليه يعتبر المكان والتنمية وما ينبثق عنهما من مفاهيم وأبعاد أساس العمل التنموي وموجهاً رئيسياً له. لقد أدى جذب منطقة الغاب للمشاريع التنموية منذ منتصف القرن الماضي وحتى الآن إلى نشوء وتطور تجمعات سكانية متفرقة في ريف هذا السهل وعلى امتداد مساحته وبنسب كبيرة من الأراضي المستصلحة منه, كما وأدى إلى ارتفاع معدلات النمو السكاني لتفوق معدلات النمو القومي للسكان في سوريا حيث بلغ معدل النمو السكاني لإقليم الغاب الإداري للفترة الزمنية بين عامي (1970ـ1981) قيمة (0.047) بينما كانت على مستوى سوريا (0.034). في ظل غياب التوازن المكاني لتوزيع تلك المشاريع وعدم انسجامها مع المقومات الطبيعية والبشرية, حيث لم تأخذ بالاعتبار الملائمة المكانية وخصوصية المنطقة ما أدى إلى التعدي على الأراضي الزراعية وتحويلها للاستعمال السكني واستنزاف الكثير من الموارد التي تحويها. يهدف هذا البحث إلى تقييم الملائمة المكانية لمشروع التنمية الشاملة لسهل الغاب (الآغروبوليس) عبر منهجية تحليلية مكانية تسعى للحفاظ على الموارد الطبيعية المتمثلة بالأراضي الزراعية والغابات الحراجية وعدم البناء على حسابها، والربط بين البيئة الطبيعية وانعكاس مؤثراتها على النشاط البشري. كما يهدف لوضع تصور لتوزيع مشاريع التنمية في المواقع الأكثر ملائمة بالنظر لخصائص المكان

    Application of recommended therapies among patients with heart failure during the Syrian conflict : reality and barriers

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    Aims Lower socio-economic status may delay and even prevent the application of guideline-directed heart failure (HF) therapy for most patients. This study aims to evaluate the feasibility and possible difficulties facing the application of this treatment during the current Syrian conflict. Methods and results A questionnaire on HF management and feasibility of recommended HF therapy was addressed to physicians practising cardiology in Syria. The questionnaire consisted of 30 questions and focused on the quality of HF management and awareness of recommended drug and device therapy for HF among physicians practising cardiology in Syria. A total of 228 physicians participated in the survey. Awareness of recommended medical and device therapy of HF was very high among participants (98% and 95%, respectively). The majority of participants (>75%) believe that more than half of HF patients do not receive optimal medical HF therapy. Ninety per cent of participants believe that <10% of patients with an appropriate indication for device therapy receive it. More than 75% of participants believe that the cost of medications, alone or in combination with other medical causes, represents the major problem facing the application of optimal HF medical therapy. More than 95% of participants reported that cost alone, or in combination with unavailability, is the primary reason why patients with appropriate indications are not offered device therapy. Conclusions Despite the high level of awareness of recommended HF therapies among Syrian cardiologists, the majority of HF patients are still undertreated. Financial difficulties and lack of resources are the main causes of this problem

    Oscillatory behavior of Pd-Au catalysts in toluene total oxidation

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    In this work, the activity of bimetallic Pd-Au doped hierarchically structured titania catalysts has been investigated in the total oxidation of toluene. In earlier works, doping titania with group Vb metal oxides ensured an increased catalytic performance in the elimination of VOC molecules. A synergy between gold and palladium loaded at the surface of titania supports provided better performances in VOC oxidation reactions. Therefore, the main focus in this work was to investigate the durability of the prepared catalysts under long time-on-stream periods. Vanadium-doped catalysts showed a stable activity throughout the whole 110 h test, whereas, surprisingly, niobium-doped catalysts presented a cycle-like activity while nevertheless maintaining a high performance in toluene elimination. Operando Diffuse Reflectance Infrared Fourrier Transform spectroscopy (DRIFT) experiments revealed that variations in the presence of OH radicals and the presence of carbonaceous compounds adsorbed at the surface of spent catalysts varies with the occurrence of oscillations. X-ray Photoelectron Spectroscopy (XPS) results show that interactions between the material and the active phase provided extra amounts of mobile oxygen species and participated in easing the reduction of palladium. An enhanced redox reaction scheme is thus obtained and allows the occurrence of the cyclic-like performance of the catalyst

    Laparoscopy in management of appendicitis in high-, middle-, and low-income countries: a multicenter, prospective, cohort study.

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    BACKGROUND: Appendicitis is the most common abdominal surgical emergency worldwide. Differences between high- and low-income settings in the availability of laparoscopic appendectomy, alternative management choices, and outcomes are poorly described. The aim was to identify variation in surgical management and outcomes of appendicitis within low-, middle-, and high-Human Development Index (HDI) countries worldwide. METHODS: This is a multicenter, international prospective cohort study. Consecutive sampling of patients undergoing emergency appendectomy over 6 months was conducted. Follow-up lasted 30 days. RESULTS: 4546 patients from 52 countries underwent appendectomy (2499 high-, 1540 middle-, and 507 low-HDI groups). Surgical site infection (SSI) rates were higher in low-HDI (OR 2.57, 95% CI 1.33-4.99, p = 0.005) but not middle-HDI countries (OR 1.38, 95% CI 0.76-2.52, p = 0.291), compared with high-HDI countries after adjustment. A laparoscopic approach was common in high-HDI countries (1693/2499, 67.7%), but infrequent in low-HDI (41/507, 8.1%) and middle-HDI (132/1540, 8.6%) groups. After accounting for case-mix, laparoscopy was still associated with fewer overall complications (OR 0.55, 95% CI 0.42-0.71, p < 0.001) and SSIs (OR 0.22, 95% CI 0.14-0.33, p < 0.001). In propensity-score matched groups within low-/middle-HDI countries, laparoscopy was still associated with fewer overall complications (OR 0.23 95% CI 0.11-0.44) and SSI (OR 0.21 95% CI 0.09-0.45). CONCLUSION: A laparoscopic approach is associated with better outcomes and availability appears to differ by country HDI. Despite the profound clinical, operational, and financial barriers to its widespread introduction, laparoscopy could significantly improve outcomes for patients in low-resource environments. TRIAL REGISTRATION: NCT02179112

    Global economic burden of unmet surgical need for appendicitis

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    Background: There is a substantial gap in provision of adequate surgical care in many low-and middle-income countries. This study aimed to identify the economic burden of unmet surgical need for the common condition of appendicitis. Methods: Data on the incidence of appendicitis from 170 countries and two different approaches were used to estimate numbers of patients who do not receive surgery: as a fixed proportion of the total unmet surgical need per country (approach 1); and based on country income status (approach 2). Indirect costs with current levels of access and local quality, and those if quality were at the standards of high-income countries, were estimated. A human capital approach was applied, focusing on the economic burden resulting from premature death and absenteeism. Results: Excess mortality was 4185 per 100 000 cases of appendicitis using approach 1 and 3448 per 100 000 using approach 2. The economic burden of continuing current levels of access and local quality was US 92492millionusingapproach1and92 492 million using approach 1 and 73 141 million using approach 2. The economic burden of not providing surgical care to the standards of high-income countries was 95004millionusingapproach1and95 004 million using approach 1 and 75 666 million using approach 2. The largest share of these costs resulted from premature death (97.7 per cent) and lack of access (97.0 per cent) in contrast to lack of quality. Conclusion: For a comparatively non-complex emergency condition such as appendicitis, increasing access to care should be prioritized. Although improving quality of care should not be neglected, increasing provision of care at current standards could reduce societal costs substantially

    Pooled analysis of WHO Surgical Safety Checklist use and mortality after emergency laparotomy

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    Background The World Health Organization (WHO) Surgical Safety Checklist has fostered safe practice for 10 years, yet its place in emergency surgery has not been assessed on a global scale. The aim of this study was to evaluate reported checklist use in emergency settings and examine the relationship with perioperative mortality in patients who had emergency laparotomy. Methods In two multinational cohort studies, adults undergoing emergency laparotomy were compared with those having elective gastrointestinal surgery. Relationships between reported checklist use and mortality were determined using multivariable logistic regression and bootstrapped simulation. Results Of 12 296 patients included from 76 countries, 4843 underwent emergency laparotomy. After adjusting for patient and disease factors, checklist use before emergency laparotomy was more common in countries with a high Human Development Index (HDI) (2455 of 2741, 89.6 per cent) compared with that in countries with a middle (753 of 1242, 60.6 per cent; odds ratio (OR) 0.17, 95 per cent c.i. 0.14 to 0.21, P <0001) or low (363 of 860, 422 per cent; OR 008, 007 to 010, P <0.001) HDI. Checklist use was less common in elective surgery than for emergency laparotomy in high-HDI countries (risk difference -94 (95 per cent c.i. -11.9 to -6.9) per cent; P <0001), but the relationship was reversed in low-HDI countries (+121 (+7.0 to +173) per cent; P <0001). In multivariable models, checklist use was associated with a lower 30-day perioperative mortality (OR 0.60, 0.50 to 073; P <0.001). The greatest absolute benefit was seen for emergency surgery in low- and middle-HDI countries. Conclusion Checklist use in emergency laparotomy was associated with a significantly lower perioperative mortality rate. Checklist use in low-HDI countries was half that in high-HDI countries.Peer reviewe

    Measurement and interpretation of same-sign W boson pair production in association with two jets in pp collisions at s = 13 TeV with the ATLAS detector

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    This paper presents the measurement of fducial and diferential cross sections for both the inclusive and electroweak production of a same-sign W-boson pair in association with two jets (W±W±jj) using 139 fb−1 of proton-proton collision data recorded at a centre-of-mass energy of √s = 13 TeV by the ATLAS detector at the Large Hadron Collider. The analysis is performed by selecting two same-charge leptons, electron or muon, and at least two jets with large invariant mass and a large rapidity diference. The measured fducial cross sections for electroweak and inclusive W±W±jj production are 2.92 ± 0.22 (stat.) ± 0.19 (syst.)fb and 3.38±0.22 (stat.)±0.19 (syst.)fb, respectively, in agreement with Standard Model predictions. The measurements are used to constrain anomalous quartic gauge couplings by extracting 95% confdence level intervals on dimension-8 operators. A search for doubly charged Higgs bosons H±± that are produced in vector-boson fusion processes and decay into a same-sign W boson pair is performed. The largest deviation from the Standard Model occurs for an H±± mass near 450 GeV, with a global signifcance of 2.5 standard deviations

    Studies of new Higgs boson interactions through nonresonant HH production in the b¯bγγ fnal state in pp collisions at √s = 13 TeV with the ATLAS detector

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    A search for nonresonant Higgs boson pair production in the b ¯bγγ fnal state is performed using 140 fb−1 of proton-proton collisions at a centre-of-mass energy of 13 TeV recorded by the ATLAS detector at the CERN Large Hadron Collider. This analysis supersedes and expands upon the previous nonresonant ATLAS results in this fnal state based on the same data sample. The analysis strategy is optimised to probe anomalous values not only of the Higgs (H) boson self-coupling modifer κλ but also of the quartic HHV V (V = W, Z) coupling modifer κ2V . No signifcant excess above the expected background from Standard Model processes is observed. An observed upper limit µHH &lt; 4.0 is set at 95% confdence level on the Higgs boson pair production cross-section normalised to its Standard Model prediction. The 95% confdence intervals for the coupling modifers are −1.4 &lt; κλ &lt; 6.9 and −0.5 &lt; κ2V &lt; 2.7, assuming all other Higgs boson couplings except the one under study are fxed to the Standard Model predictions. The results are interpreted in the Standard Model efective feld theory and Higgs efective feld theory frameworks in terms of constraints on the couplings of anomalous Higgs boson (self-)interactions
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