Operations

Distribution by Scientific Domains

Kinds of Operations

  • arithmetic operations
  • boolean operations
  • business operations
  • cardiac operations
  • control operations
  • cutting operations
  • day-to-day operations
  • different operations
  • elective operations
  • firm operations
  • food processing operations
  • gate operations
  • logic gate operations
  • logic operations
  • manufacturing operations
  • mathematical operations
  • military operations
  • mining operations
  • multiple operations
  • new operations
  • normal operations
  • peacekeeping operations
  • processing operations
  • salvage operations
  • surgical operations
  • symmetry operations
  • system operations
  • unit operations

  • Terms modified by Operations

  • operations center
  • operations management
  • operations strategy
  • operations used

  • Selected Abstracts


    BROKERAGE QUALIFICATIONS IN RINGING OPERATIONS,

    CRIMINOLOGY, Issue 1 2008
    CARLO MORSELLI
    Brokers are fundamental for maintaining flexibility in the networks that embed criminal activities. Our study aims at offering more precision on this key issue by examining the impact that brokers may have on crime-commission processes. To do so, we analyze two stolen-vehicle exportation (or ringing) operations within a framework that merges crime-script analysis and social-network analysis. We assess how diverse degrees of brokerage are distributed across the ringing operations and how the removal of key brokers would have had a disruptive impact by reducing the scope of alternatives for crime-script permutation and flexibility. [source]


    FEDERAL SUPPORT OF LOCAL CRIMINAL JUSTICE OPERATIONS*

    CRIMINOLOGY AND PUBLIC POLICY, Issue 3 2008
    ALFRED BLUMSTEIN
    First page of article [source]


    ENVIRONMENTAL MANAGEMENT AND OPERATIONS: INTRODUCTION TO PART 2 (INTEGRATING OPERATIONS AND ENVIRONMENTAL MANAGEMENT SYSTEMS)

    PRODUCTION AND OPERATIONS MANAGEMENT, Issue 3 2001
    CHARLES J. CORBETT
    No abstract is available for this article. [source]


    RISK FACTORS FOR PERI-OPERATIVE STROKE COMPLICATING CAROTID ENDARTERECTOMY: SELECTIVE ANALYSIS OF A PROSPECTIVE AUDIT OF 1000 CONSECUTIVE OPERATIONS

    ANZ JOURNAL OF SURGERY, Issue 1 2000
    J. E. Frawley
    Background: The aim of the present study was to investigate the role of potential clinical risk factors in the causation of peri-operative stroke associated with carotid endarterectomy. With the change in carotid endarterectomy practice from the use of a shunt to high-dose thiopental for cerebral protection (a previously undocumented method), it was essential to identify accurately the causes of all peri-operative strokes. Methods: A prospective audit was undertaken of 1000 carotid endarterectomies in which the causes and pathology of all peri-operative strokes were documented. The roles of advanced age, female gender, hypertension, previous stroke, contralateral carotid stenosis > 70%, and contralateral carotid occlusion as potential causes of peri-operative stroke were defined. Results were statistically analysed using odds ratio and Fisher's exact test. Results: None of the potential risk factors was statistically significant for peri-operative stroke. Female gender was associated with a significant risk of peri-operative stroke due to operative site thrombosis. Complications at the endarterectomy site were the commonest cause of stroke. Conclusions: Prospective audit is a useful tool for identifying causes of peri-operative stroke and indicating the need for modifications to surgical clinical management which might improve outcomes for carotid endarterectomy. [source]


    Snap: A time critical decision-making framework for MOUT simulations

    COMPUTER ANIMATION AND VIRTUAL WORLDS (PREV: JNL OF VISUALISATION & COMPUTER ANIMATION), Issue 3-4 2008
    Shang-Ping Ting
    Abstract Deliberative reasoning based on the rational analysis of various alternatives often requires too much information and may be too slow in time critical situations. In these situations, humans rely mainly on their intuitions rather than some structured decision-making processes. An important and challenging problem in Military Operations on Urban Terrain (MOUT) simulations is how to generate realistic tactical behaviors for the non-player characters (also known as bots), as these bots often need to make quick decisions in time-critical and uncertain situations. In this paper, we describe our work on Snap, a time critical decision-making framework for the bots in MOUT simulations. The novel features of Snap include case-based reasoning (CBR) and thin slicing. CBR is used to make quick decisions by comparing the current situation with past experience cases. Thin slicing is used to model human's ability to quickly form up situation awareness under uncertain and complex situations using key cues from partial information. To assess the effectiveness of Snap, we have integrated it into Twilight City, a virtual environment for MOUT simulations. Experimental results show that Snap is very effective in generating quick decisions during time critical situations for MOUT simulations. Copyright 2008 John Wiley & Sons, Ltd. [source]


    Algorithm for Accurate Three-Dimensional Scene Graph Updates in High-Speed Animations of Previously Simulated Construction Operations

    COMPUTER-AIDED CIVIL AND INFRASTRUCTURE ENGINEERING, Issue 3 2009
    Prasant V. Rekapalli
    Early efforts resulted in a scene graph and frame update algorithm that was capable of converting discrete information from simulation models into smooth and continuous 3D animations. That algorithm did not account for high speed or concurrent animation because the need to do so was not anticipated. Recent advances in computing power and an interest in using the technology for next generation applications now demand accurate high speed and concurrent animations. This article presents the design of the original algorithm at a previously undocumented level of detail and specificity, and that allows for the analysis of its shortcomings when used at high speeds or concurrently with simulation. Two subsequent but still inadequate designs of the algorithm are also presented and analyzed in detail so that they can serve as an illustration of the path toward the final design and place it in proper context. The article concludes with the final design and evaluation of the algorithm, which is accurate at very high animation speeds and supports concurrent animation of simulation models. [source]


    On-Line Control Architecture for Enabling Real-Time Traffic System Operations

    COMPUTER-AIDED CIVIL AND INFRASTRUCTURE ENGINEERING, Issue 5 2004
    Srinivas Peeta
    Critical to their effectiveness are the control architectures that provide a blueprint for the efficient transmission and processing of large amounts of real-time data, and consistency-checking and fault tolerance mechanisms to ensure seamless automated functioning. However, the lack of low-cost, high-performance, and easy-to-build computing environments are key impediments to the widespread deployment of such architectures in the real-time traffic operations domain. This article proposes an Internet-based on-line control architecture that uses a Beowulf cluster as its computational backbone and provides an automated mechanism for real-time route guidance to drivers. To investigate this concept, the computationally intensive optimization modules are implemented on a low-cost 16-processor Beowulf cluster and a commercially available supercomputer, and the performance of these systems on representative computations is measured. The results highlight the effectiveness of the cluster in generating substantial computational performance scalability, and suggest that its performance is comparable to that of the more expensive supercomputer. [source]


    Scene Graph and Frame Update Algorithms for Smooth and Scalable 3D Visualization of Simulated Construction Operations

    COMPUTER-AIDED CIVIL AND INFRASTRUCTURE ENGINEERING, Issue 4 2002
    Vineet R. Kamat
    One of the prime reasons inhibiting the widespread use of discrete-event simulation in construction planning is the absence of appropriate visual communication tools. Visualizing modeled operations in 3D is arguably the best form of communicating the logic and the inner working of simulation models and can be of immense help in establishing the credibility of analyses. New software development technologies emerge at incredible rates that allow engineers and scientists to create novel, domain-specific applications. The authors capitalized on a computer graphics technology based on the concept of the scene graph to design and implement a general-purpose 3D visualization system that is simulation and CAD-software independent. This system, the Dynamic Construction Visualizer, enables realistic visualization of modeled construction operations and the resulting products and can be used in conjunction with a wide variety of simulation tools. This paper describes the scene graph architecture and the frame updating algorithms used in designing the Dynamic Construction Visualizer. [source]


    Letter: The Erasure of Skin Marks during Dermatologic Operations

    DERMATOLOGIC SURGERY, Issue 9 2007
    JAE EUN CHOI MD
    No abstract is available for this article. [source]


    Oxford experience with neoadjuvant chemotherapy and surgical resection for esophageal adenocarcinomas and squamous cell tumors

    DISEASES OF THE ESOPHAGUS, Issue 3 2008
    P. M. Safranek
    SUMMARY., The Medical Research Council trial for oesophageal cancer (OEO2) trial demonstrated a clear survival benefit from neoadjuvant chemotherapy in resectable esophageal carcinoma. Since February 2000 it has been our practice to offer this chemotherapy regime to patients with T2 and T3 or T1N1 tumors. We analyzed prospectively collected data of patients who received neoadjuvant chemotherapy prior to esophageal resection under the care of a single surgeon. Complications of treatment and overall outcomes were evaluated. A total of 194 patients had cisplatin and 5-fluorouracil prior to esophageal resection. Six patients (5.7%) had progressive disease and were inoperable (discovered in four at surgery). During chemotherapy one patient died and one perforated (operated immediately). Complications including severe neutropenia, coronary artery spasm, renal impairment and pulmonary edema led to the premature cessation of chemotherapy in 12 patients (6.2%). A total of 182 patients with a median age of 63 (range 30,80), 41 squamous and 141 adenocarcinomas underwent surgery. Operations were 91 left thoracoabdominal (50%), 45 radical transhiatal (25%), 40 Ivor-Lewis (22%) and six stage three (3%), and 78.6% had microscopically complete (R0) resections. Median survival was 28 months with 77.3% surviving for 1 year and 57.7% for 2 year. In hospital mortality was 5.5% and anastomotic leak rate 7.7%. A radical surgical approach to the primary tumor in combination with OEO2 neoadjuvant chemotherapy has led to a high R0 resection rate and good survival with acceptable morbidity and mortality. [source]


    Crystalline , -Alumina Deposited in an Industrial Coating Unit for Demanding Turning Operations,

    ADVANCED ENGINEERING MATERIALS, Issue 1-2 2010
    Kirsten Bobzin
    Crystalline PVD ,-Al2O3 - coatings offer great potential for their use in high-speed cutting operations. They promise high hot hardness and high oxidation resistance at elevated temperatures. This is important for coatings that are used for machining of materials with low thermal conductivity such as stainless steel or Inconel 718 because heat generated during cutting can barely be dissipated by the chip. Because of the prevailing bonding forces of alumina, adhesion-related sticking can be reduced even for dry cutting. Furthermore, the high formation enthalpy of alumina prevents chemical reactions with frictional partners. The present work gives an overview of the deposition of ,-Al2O3 thin films on WC/Co-cutting inserts by using pulsed MSIP (magnetron sputter ion plating) PVD technology. To improve adhesion, a (Ti,Al)N bond coat was employed. The samples were analyzed using common thin film test equipment. Cutting tests and pin-on-disk examinations were carried out to test the coating's performance. For turning operations, the difficult-to-machine austenitic steel 1.4301 (X5CrNi18-10) was used. In comparison to a state-of-the-art (Ti,Al)N coating, (Ti,Al)N/,-Al2O3 showed a longer tool life. [source]


    Thermal Investigation of Al2O3 Thin Films for Application in Cutting Operations,

    ADVANCED ENGINEERING MATERIALS, Issue 7 2009
    Kirsten Bobzin
    Crystalline PVD ,-Al2O3 coatings offer great potential for use in high-speed cutting operations. They offer specific high temperature features, like high hot hardness and high oxidation resistance. However, the reasons for the high thermal stability of this system are not clearly understood. In this paper, the phase and oxidation stability of thin ,-Al2O3 films (as illustrated in the micrograph) are investigated. [source]


    Elite Consensus as a Determinant of Alliance Cohesion: Why Public Opinion Hardly Matters for NATO-led Operations in Afghanistan

    FOREIGN POLICY ANALYSIS, Issue 3 2010
    Sarah Kreps
    Despite the increasing popularity of fighting wars through multilateral coalitions, scholars have largely been silent on the question of how public opinion in member states affects alliance cohesion. This article assesses public opinion data for states contributing to operations in Afghanistan. It finds that despite the unpopularity of the war, leaders have largely bucked public opinion and neither reduced nor withdrawn troops from NATO-led operations in Afghanistan. Theoretical expectations about international cooperation and evidence from case studies point to elite consensus as the reason why leaders are not running for the exits in Afghanistan when their publics would prefer that they do. As the article shows, operating through a formal institution such as NATO creates systemic incentives for sustained international cooperation. The result is that elite consensus inoculates leaders from electoral punishment and gives states' commitments to Afghanistan a "stickiness" that defies negative public opinion. A formal alliance such as NATO may therefore create more policy constraints than an ad hoc coalition but also increase the costs of defection and confer a degree of staying power that is unexpected given the adverse public opinion environment. [source]


    Emergence of New Mechanical Functionality in Materials via Size Reduction

    ADVANCED FUNCTIONAL MATERIALS, Issue 18 2009
    Julia R. Greer
    Abstract Julia R. Greer received her S.B. in Chemical Engineering from the Massachusetts Institute of Technology (1997) and a Ph.D. in Materials Science from Stanford University, where she worked on the nanoscale plasticity of gold with W. D. Nix (2005). She also worked at Intel Corporation in Mask Operations (2000,03) and was a post-doctoral fellow at the Palo Alto Research Center (2005,07), where she worked on organic flexible electronics with R. A. Street. Greer is a recipient of TR-35, Technology Review's Top Young Innovator award (2008), a NSF CAREER Award (2007), a Gold Materials Research Society Graduate Student Award (2004), and an American Association of University Women Fellowship (2003). Julia joined Caltech's Materials Science department in 2007 where she is developing innovative experimental techniques to assess mechanical properties of nanometer-sized materials. One such approach involves the fabrication of nanopillars with different initial microstructures and diameters between 25,nm and 1,m by using focused ion beam and electron-beam lithography microfabrication. The mechanical response of these pillars is subsequently measured in a custom-built in situ mechanical deformation instrument, SEMentor, comprising a scanning electron microscope and a nanoindenter. Read our interview with Prof. Greer on MaterialsViews.com [source]


    Free-Standing Biodegradable Poly(lactic acid) Nanosheet for Sealing Operations in Surgery

    ADVANCED MATERIALS, Issue 43 2009
    Yosuke Okamura
    A free-standing biodegradable nanosheet composed of poly(L -lactic acid) (PLLA) was shown to have excellent sealing efficacy for a gastric incision as a novel wound dressing material that did not require adhesive agents, and the PLLA nanosheet-induced wound repair showed neither scars nor tissue adhesion. This material may, therefore, be an ideal alternative to conventional tissue repairing procedures using suture/ligation in surgery. [source]


    Incidence of inflammatory bowel disease in finnish children, 1987,2003

    INFLAMMATORY BOWEL DISEASES, Issue 8 2006
    Pieta Turunen MS
    Abstract Background: The incidence of inflammatory bowel disease (IBD) has been increasing in Western countries. In younger people, Crohn's disease (CD) predominates over ulcerative colitis (UC), but the finding is not universal. The present study aimed to characterize not only the incidence but also the clinical picture of IBD from 1987 to 2003 in a large pediatric population in Finland. Materials and Methods: Data were collected from the patient discharge and medical records at the 2 largest university hospitals in Finland. The study population covered a total of 619,340 children, representing 56% of the children <18 years old in the country. All of the cases diagnosed with IBD from 1987 to 2003 were reviewed. Clinical, endoscopic, and histological data were collected. Incidence rates were estimated based on statistical assumptions. Results: A total of 604 cases with IBD were diagnosed during the 17-year period. All of the patients had undergone endoscopy. The diagnosis was CD in 203 (34%) cases, UC in 317 (52%) cases, and indeterminate colitis (IC) in 83 (14%) cases. The mean annual incidence rate increased from 3.9/100,000 (95% confidence interval [CI] 2.5,5.8) in 1987 to 7.0/100,000 (CI 5.0,9.4) in 2003 (P < 0.001). The majority of cases were 12 to <15 years old (n = 200, 33%). Of the patients, 5.1% were <3 years old and 14% were <6 years old. IC was most common in young children; 29% of all IBD patients <3 years of age had IC. Of the patients, 97% had been followed up until the age 18 in the hospitals after initial diagnosis (median follow-up 3.1 years). Of the patients, 45.2% were initially treated with steroids, whereas 17.8% received immunosuppressive agents at the end of the follow-up. Operations had been performed in 21% of the cases before age 18. The median time interval from the diagnosis to the first operation was 1.8 (range 7.8) years. Conclusions: The incidence of pediatric IBD almost doubled in Finland from 1987 to 2003. Surgical intervention was common early in the disease course. [source]


    Phase Separation of Polyfluorene-Based Blend Films and Its Influence on Device Operations,

    ADVANCED MATERIALS, Issue 11 2006
    Y. Xia
    Vertical phase separations have been found in blend films (TFB:F8BT) of polymer light-emitting diodes, giving rise to better device performances. A TFB wetting layer is present over most of the bottom interface with the substrate, as evidenced by the fluorescent microscopy images after top layers are etched away by oxygen plasma (see figure). [source]


    Big Gun Monitors: Design, Construction and Operations 1914,1945

    INTERNATIONAL JOURNAL OF NAUTICAL ARCHAEOLOGY, Issue 2 2009
    ANDREW LAMBERT
    No abstract is available for this article. [source]


    Using Role-Play Scenarios in the IR Classroom: An Examination of Exercises on Peacekeeping Operations and Foreign Policy Decision Making

    INTERNATIONAL STUDIES PERSPECTIVES, Issue 1 2004
    Carolyn M. Shaw
    Use of role-play scenarios in the classroom is just one of a number of active learning techniques that are being used more and more frequently to convey the more abstract concepts of international relations (IR) to students in a meaningful way. This paper examines the value of two specific role-play exercises used in an introduction to international relations course on the topics of peacekeeping and foreign policy decision making. The value of such interactive exercises is laid out in a section examining what learning objectives can be achieved by using role-play scenarios. These include promoting student interaction and input, and promoting student curiosity and creativity. The preparations necessary for conducting such an exercise are laid out, followed by a description of the exercises as they were conducted in the classroom. Finally, an assessment of the exercises provides useful feedback on the degree to which specific learning objectives were achieved, and how such exercises can be modified to be even more effective. [source]


    Can Peacekeeping Operations Promote Democracy?

    INTERNATIONAL STUDIES REVIEW, Issue 2 2005
    Birger Heldt
    First page of article [source]


    Use of Biodegradable Annuloplasty Ring For Pediatric Valvuloplasty Operations

    JOURNAL OF CARDIAC SURGERY, Issue 2 2008
    Mustafa Cikirikcioglu M.D., Ph.D.
    No abstract is available for this article. [source]


    Environmental Impact and Added Value in Forestry Operations in Norway

    JOURNAL OF INDUSTRIAL ECOLOGY, Issue 1 2008
    Ottar Michelsen
    Summary The forestry sector is experiencing an increasing demand for documentation about its environmental performance. Previous studies have revealed large differences in environmental impact caused by forestry operations, mainly due to differences in location and forestry practice. Reliable information on environmental performance for forestry operations in different regions is thus important. This article presents a case study of forestry operations in Norway. Environmental impact and value added of selected operations were assessed. This was done with a hybrid life cycle assessment (LCA) approach. Main results, including a sensitivity analysis, are presented for a set of four impact categories. The production chain assessed included all processes from seedling production to the delivery of logs to a downstream user. The environmental impact was mainly caused by logging, transport by forwarders, and transport by truck. These three operations were responsible for approximately 85% of the total environmental impact. The contribution to value added and total costs were more evenly distributed among the processes in the value chain. The sensitivity analysis revealed that the difference in environmental impact between the worst case scenario and the best case scenario was more than a factor of 4. The single most important process was the transport distance from the timber pile in the forest to the downstream user. The results show that the environmental impact from forestry operations in boreal forests was probably underreported in earlier studies. [source]


    Is there an indication for initial conservative management of pancreatic cystic lesions?,

    JOURNAL OF SURGICAL ONCOLOGY, Issue 5 2009
    Stephen R. Grobmyer MD
    Abstract Background The management of small pancreatic cystic lesions presents a clinical challenge. Methods We reviewed our experience with 78 patients who presented with a cystic pancreatic lesion who underwent operative management between 1995 and 2005. Data on cyst characteristics were analyzed in the context of pathologic findings following resection. Results Among 78 patients, there were 55 (71%) females; median age 63 years. Patients presented with: an incidental finding (48%), pain (40%), acute pancreatitis (4%), other (8%). Operations were distal pancreatectomy (n,=,47), pancreaticoduodenectomy (n,=,16), and other (n,=,15). Most patients had a non-malignant lesion (n,=,65, 83%) (mucinous cystadenoma (n,=,29), serous cystadenoma (n,=,15), IPMN without invasion (n,=,8), pseudocyst (n,=,8), other benign (n,=,5)). Malignant lesions (adenocarcinoma, neuroendocrine tumor, and other) were found in 13 patients (17%). The risk of malignancy increased with size: <3 cm (n,=,25), 4%; 3,5 cm (n,=,23), 13%; and >5 cm (n,=,30), 30%. Pre-operative cyst fluid cytology was performed in 41 patients. The negative predictive value (NPV) of cytology for malignancy was 88% and the positive predictive value (PPV) was 80%. The NPV of CA 19-9 for malignancy was 90%; the PPV was 50%. Conclusions Initial conservative management of small cystic pancreatic lesions may be indicated in selected patients. J. Surg. Oncol. 2009;100:372,374. 2009 Wiley-Liss, Inc. [source]


    Impacts of Alternative Manure Application Rates on Texas Animal Feeding Operations: A Macro Level Analysis,

    JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION, Issue 3 2008
    E. Osei
    Abstract:, An integrated economic and environmental modeling system was developed for evaluating agro-environmental policies and practices implemented on large scales. The modeling system, the Comprehensive Economic and Environmental Optimization Tool-Macro Modeling System (CEEOT-MMS), integrates the Farm-level Economic Model (FEM) and the Agricultural Policy Environmental eXtender (APEX) model, as well as national databases and clustering and aggregation algorithms. Using micro simulations of statistically derived representative farms and subsequent aggregation of farm-level results, a wide range of agricultural best management practices can be investigated within CEEOT-MMS. In the present study, CEEOT-MMS was used to evaluate the economic and water quality impacts of nitrogen (N) and phosphorus (P) based manure application rates when implemented on all animal feeding operations in the State of Texas. Results of the study indicate that edge-of-field total P losses can be reduced by about 0.8 kg/ha/year or 14% when manure applications are calibrated to supply all of the recommended crop P requirements from manure total P sources only, when compared to manure applications at the recommended crop N agronomic rate. Corresponding economic impacts are projected to average a US$4,800 annual cost increase per farm. Results are also presented by ecological subregion, farm type, and farm size categories. [source]


    Warfighter Needs in the 21st Century: Linking Fleet Operations to Required Capabilities

    NAVAL ENGINEERS JOURNAL, Issue 4 2000
    Capt. V.A. Myer USNR (Ret.)
    ABSTRACT What the warfighter needs is not what he is getting in terms of responsiveness to the emerging threat, interoperability among systems, and systems readiness and training. This disconnect between Fleet operations and the acquisition requirements process is becoming more pronounced as systems grow larger and more complex and as warflghting becomes more joint Knowing what the warfighter wants and how he envisions using it in a concept of operations is fundamental to the requirements process. The source of this information is the commander in chief's (CINC's) operations plan (OPLAN), which contains the concept of operations (CONOPS) for each warfighting theater. It is critical that the CONOPS be used as the basis for determining performance requirements, because it contains the military judgment, context, and authority of the theater CINC. The defunct Arsenal Ship program, which was rightly vetoed by the theater CINCs because it would not meet their warfighting needs at acceptable risk, is a recent example of the mismatch between what is being asked for and what is being provided. [source]


    Designing Agendas to Reflect Board Roles and Responsibilities: Results of a Study

    NONPROFIT MANAGEMENT & LEADERSHIP, Issue 1 2000
    Sue Inglis
    Over a nine-month period the board agendas of a community nonprofit organization were redesigned to reflect a particular board agenda tool titled "Strategic Activities, Resource Planning, and Operations." Feedback from the board members and executive director indicate strong support for the framework in focusing the work of the board. The framework also has implications for how the executive director and board members prepare for meetings and how the shared leadership of the meetings is played out. [source]


    Use of Radiofrequency Perforation for Lead Placement in Biventricular or Conventional Endocardial Pacing after Mustard or Senning Operations for D-Transposition of the Great Arteries

    PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 9 2009
    SANTABHANU CHAKRABARTI M.D.
    Background: Endocardial pacemaker lead placement can be challenging after Mustard and Senning operations for transposition of the great arteries (D-TGA), if there is atresia of the systemic venous pathways and because the coronary sinus cannot be used for cardiac resynchronization therapy. Radiofrequency (RF)-assisted perforation techniques have been used in congenital heart disease but have not been reported for use in pacemaker implantation. Methods and Results: We describe RF perforation of an atretic superior systemic venous pathway and systemic venous baffles in three patients after Senning and Mustard operations to implant endocardial pacing systems to achieve conventional or biventricular pacing. Conclusions: RF-energy-assisted perforation is feasible and effective tool to facilitate endocardial lead placement during dual-chamber and biventricular pacemaker implantation in patients with Mustard or Senning operations for D-TGA. [source]


    DDD Pacemaker Implantation After Fontan-Type Operations

    PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 1p2 2003
    MARKUS K. HEINEMANN
    HEINEMANN, M.K., et al.: DDD Pacemaker Implantation After Fontan-Type Operations.Bradyarrhythmias developing after Fontan-type operations impair the function of the univentricular heart causing fatigue, headaches, ascites, and protein-losing enteropathy (PLE). Transvenous inaccessibility, requiring epicardial implantation, accounts for the reluctance to implant a pacemaker (PM). Between 1997 and 2000, 24 patients (mean age 9.5 years, range 6 months to 19 years) with Fontan-type operations received DDD pacing systems with atrial steroid-eluting stitch-on electrodes (mean capture threshold 1.9 V/0.5 ms, range 0.4,3.5 V) and ventricular screw-in electrodes (mean capture threshold 1.7 V/0.5 ms, range 0.1,3 V). The systems were implanted at the time of conversion from atrio- to cavopulmonary connections in 5 patients, at the time of a total cavopulmonary Fontan operation in 6, and 1,50 months thereafter (mean = 18) in 13 patients. A right ventricular anatomy was present in 13 (54%) of 24 of PM recipients, versus 35% of the overall population. After a mean follow-up of 3.5 years, the PM were functioning in DDD mode in 23 of the 24 patients. Length of hospital stay in the ten patients who underwent repeat sternotomy was 5 days, without procedure related complications. In three children a repeat sternotomy was avoided by implanting the atrial electrodes during the Fontan operation. All patients improved clinically, including resolution of PLE in four patients. Bradyarrhythmias may lead to significant morbidity after Fontan-type operations. Electrophysiological evaluation is advised at follow-up. The indication for implantation of a DDD pacemaker system should be liberal. Placing atrial electrodes during the Fontan operation, especially in the presence of a right ventricular anatomy, avoids repeat sternotomy. (PACE 2003; 26[Pt. II]:492,495) [source]


    Pulsed Nanocomposite TiAlN Coatings on Complex Shaped Tools for High Performance Cutting Operations

    PLASMA PROCESSES AND POLYMERS, Issue S1 2007
    Kirsten Bobzin
    Abstract The demand on high profitability in cutting operations has led to a variety of requirements for high performance tool coatings. Nanostructured coatings have shown most promising results in this connection. High oxidation resistance, hot hardness, and loW friction are just a few benefits that these coatings offer. The deposition of nanostructured coatings is only possible within a small deposition process window. Most cutting tool surfaces are complex shaped and include, for instance, small corner radii at the cutting edge or chip breakers. The local process window and the deposition parameters must be adapted to the actual shape of the cutting tools in order to obtain a hard nanocomposite coating with adequate adhesion properties. Finally, the performance of these coatings has been studied in machining tests. [source]


    The White House Office of Management and Administration

    PRESIDENTIAL STUDIES QUARTERLY, Issue 2 2001
    PERI E. ARNOLD
    The Office of Management and Administration (OMA) grew out of President Carter's 1977 reorganization of White House administration. Its title dates to the administration of George H. W. Bush. The head of the office, the assistant to the president for management and administration, currently handles numerous White House administrative functions such as salaries, office space, and budgeting, along with the allocation of perquisites like mess privileges and parking. OMA supervises units collectively called "White House Operations," including the Travel Office, the Visitors Office, the Intern Program, and personnel security. The assistant for management and administration also oversees the White House Military Office. Drawing principally on interviews with former heads of the OMA and its predecessors, this article enumerates the great range of the office's responsibilities, highlights areas of potential controversy, considers the characteristics of a successful OMA manager, and summarizes the diverse approaches that have been taken to running the office. [source]