General Electric Company Research Articles

AB1081 Results of A Walk-In Bone and Joint Screening CAMPAIGN to AID in the Diagnosis of Rheumatic Diseases

BackgroundRheumatic diseases are underdiagnosed in the Middle East. Screening and awareness campaigns can be used in conjunction with peripheral ultrasound machines used to screen for low bone mass are a...

TH-C-18A-01: Is Automatic Tube Current Modulation Still Necessary with Statistical Iterative Reconstruction?

Purpose: Automatic tube current modulation (TCM) has been widely used in modern multi-detector CT to reduce noise spatial nonuniformity and streaks to improve dose efficiency. With the advent of statistical iterative reconstruction (SIR), it is expected that the importance of TCM may diminish, since SIR incorporates statistical weighting factors to reduce the negative influence of photon-starved rays. The purpose of this work is to address the following questions: Does SIR offer the same benefits as TCM? If yes, are there still any clinical benefits to using TCM? Methods: An anthropomorphic CIRS chest phantom was scanned using a state-of-the-art clinical CT system equipped with an SIR engine (Veo™, GE Healthcare). The phantom was first scanned with TCM using a routine protocol and a low-dose (LD) protocol. It was then scanned without TCM using the same protocols. For each acquisition, both FBP and Veo reconstructions were performed. All scans were repeated 50 times to generate an image ensemble from which noise spatial nonuniformity (NSN) and streak artifact levels were quantified. Monte-Carlo experiments were performed to estimate skin dose. Results: For FBP, noise streaks were reduced by 4% using TCM for both routine and LD scans. NSN values were actually slightly higher withmore » TCM (0.25) than without TCM (0.24) for both routine and LD scans. In contrast, for Veo, noise streaks became negligible (<1%) with or without TCM for both routine and LD scans, and the NSN was reduced to 0.10 (low dose) or 0.08 (routine). The overall skin dose was 2% lower at the shoulders and more uniformly distributed across the skin without TCM. Conclusion: SIR without TCM offers superior reduction in noise nonuniformity and streaks relative to FBP with TCM. For some clinical applications in which skin dose may be a concern, SIR without TCM may be a better option. K. Li, W. Zhao, D. Gomez-Cardona: Nothing to disclose; G.-H. Chen: Research funded, General Electric Company Research funded, Siemens AG Research funded, Varian Medical Systems, Research funded, Hologic, Inc.« less

TH‐E‐17A‐09: High Quality and Artifact‐Free 4D Cone Beam CT and Its Application in Adaptive Treatment Planning

Purpose:To develop a high quality 4D cone beam CT (4DCBCT) method that is immune to patient/couch truncations and to investigate its application in adaptive replanning of lung XRT.Methods:In this study, IRB‐approved human subject CBCT data was acquired using a Varian on‐board imager with 1 minute rotation time. The acquired projection data was retrospectively sorted into 20 respiratory phase bins, from which 4DCBCT images with high SNR and high temporal resolution were generated using Prior Image Constrained Compressed Sensing (PICCS). Couch and patient truncations generate strong data inconsistency in the projection data and artifacts in the 4DCBCT image. They were addressed using an adaptive PICCS method. The artifact‐free PICCS‐4DCBCT images were used to generate adaptive treatment plans for the same patient at the 10th (day 21) and 30th (day 47) fractions. Dosimetric impacts with and without PICCS‐ 4DCBCT were evaluated by isodose distributions, DVHs, and other dosimetric factors.Results:The adaptive PICCS‐4DCBCT method improves image quality by removing residue truncation artifacts; measured universal image quality increased 37%. The isodose lines and DVHs with PICCS‐4DCBCT‐based adaptive replanning were significantly more conformal to PTV than without replanning due to changes in patient anatomy caused by progress of the treatment. The mean dose to PTV at the 10th fraction was 63.1Gy with replanning and 64.2Gy without replanning, where the prescribed dose was 60Gy, in 2Gy × 30 fractions. The mean dose to PTV at the 30th fraction was 61.6Gy with replanning and 64.9Gy without replanning. Lung V20 was 37.1%, 41.9% and 43.3% for original plan, 10th fraction plan and 30th fraction plan; with re‐planning, Lung V20 was 37.1%, 32%, 27.8%.Conclusion:4DCBCT imaging using adaptive PICCS is able to generate high quality, artifact‐free images that potentially can be used to create replanning for improving radiotherapy of the lung. K Niu, K Li, J Smilowitz: Nothing to Disclose.G Chen: General Electric Company Research funded, Siemens AG Research funded, Varian Medical Systems Research funded, Hologic Research funded.

WE‐D‐18A‐03: BEST IN PHYSICS (IMAGING) – Statistical Model Based Iterative Reconstruction (MBIR) in Clinical CT Systems: Experimental Assessment of Z‐ and Axial Spatial Resolution

Purpose:The purpose of this work was to experimentally assess the unique spatial resolution characteristics of statistical model based iterative reconstruction (MBIR) along both axial and z directions and to examine the impact of spatial resolution on the task‐based diagnostic detection performance.Methods:An anthropomorphic chest phantom was repeatedly scanned 100 times using a clinical CT scanner at four dose levels (25%, 50%, 75%, 100%). Both FBP and MBIR (Veo™) were used for reconstruction. Nine objects with contrasts ranging from 13 to 1710 HU were used to assess spatial resolution. The axial and z resolutions were quantified locally in the image domain by point spread functions (PSF) and slice sensitivity profiles (SSP) respectively. The tradeoff between local image noise and resolution and their joint impact on the channelized Hotelling observer (CHO) detectabilities (d ') was investigated.Results:The axial resolution of MBIR improved monotonically with increasing dose and contrast level (FWHM_PSF=2.0 mm at 13 HU/25% dose and was 0.8 mm 1710 HU/100% dose). In comparison, axial resolution of FBP was independent of dose and contrast (FWHM_PSF=1.2 mm). The z resolution of MBIR demonstrated similar contrast dependence but only negligible dose dependence. The spatial resolution of MBIR and FBP became equivalent at some transitional contrast levels (280 HU for 25% dose and 90 HU for 100% dose), above which MBIR demonstrated superior resolution than FBP (and vice versa). Spatial resolution and noise assessed at the same location demonstrated a strong tradeoff in MBIR, and CHO detectability index d' was improved by MBIR for all contrast and dose levels.Conclusion:MBIR produces images with unique spatial resolution characteristics and introduces new challenges to its clinical use and evaluation. One potential solution, as suggested by this work, is to perform rigorous spatial resolution and noise measurements at different dose levels for each specific task.K. Li, J. Garrett, Y. Ge: Nothing to disclose; G.‐H. Chen: Research funded, General Electric Company Research funded, Siemens AG Research funded, Varian Medical Systems, Research funded, Hologic, Inc.

An 11-stage axial compressor performance simulation considering the change of tip clearance in different operating conditions

The multistage axial compressor is one of the critical components of aero-engines and plays a key role in their performance, reliability, and economy. Tip clearance has a significant impact on the performance and stability of multistage axial compressors. Due to blade and disk deformations, tip clearance will vary significantly in different operating conditions. Thus, tip clearance should be accurately estimated when evaluating compressor performance. This paper proposes a new model to predict changes of tip clearance of multistage axial compressors in different operating conditions. A first-principles approach is used to estimate the change of tip clearance caused by thermal and mechanical deformation. The span-wise temperature distribution across each stage of the multistage compressors is considered by the proposed model in this paper. The model was validated by General Electric Company (GE) E3 engine experimental results. Using the model, the performance of an 11-stage axial compressor is simulated. The results show that accounting for tip clearance variations has a 0.5% impact on the calculated mass flow rate and a 1% impact on the calculated efficiency. Thus, variations of tip clearance at different operating conditions cannot be ignored and the proposed new model is useful to accurately predict the performance of multistage axial compressor.

A Fond Farewell to The Lab: The Demolition of Building 9 [History

Recently, I drove out the Tyler Street Extension in Pittsfield, Massachusetts, to view the ongoing demolition of Building 9 in the former General Electric Company (GE) plant. Building 9 once had been a world-renowned center of high-voltage and lightning research. It was named the GE High Voltage Laboratory and was commonly referred to as ?The Lab.?

Relationship between renal apparent diffusion coefficient values and glomerular filtration rate in infants with congenital hydronephrosis.

The aim was to investigate the relationship between apparent diffusion coefficient (ADC) values measured by diffusion-weighted magnetic resonance imaging (DW MRI) and the split glomerular filtration rate (GFR) in infants with congenital hydronephrosis. Diffusion-weighted imaging (DWI) (b = 0 and 700 seconds/mm(2)) was performed with a General Electric Company (GE) Signa 1.5T MR unit in 46 infants suffering single congenital hydronephrosis and in 30 healthy infants as normal control group. The ADCs were calculated with regions of interest (ROIs) positioned in the renal parenchyma. The 46 obstructed kidneys were classified into four groups according to the GFR level: renal dysfunction compensated group, renal dysfunction decompensated group, renal failure group, and uremia group. The renal ADCs in six groups (normal kidneys in control group, contralateral kidneys, and four groups of hydronephrotic kidneys) were compared statistically using analysis of variance (ANOVA), and the correlative relationship between ADCs and GFR was examined by Pearson's correlation test. There were statistically significant differences in renal ADCs among the six groups. The ADCs of hydronephrotic kidneys were lower than that of the normal kidneys. There was a moderate positive correlation between the ADCs of hydronephrotic kidneys and split GFR (r = 0.744). This study indicated that the ADCs of congenital hydronephrotic kidneys were lower than that of normal renal parenchyma, and there was a positive correlation between the ADCs and split renal GFR, which demonstrates that the ADCs can reflect the filtration function of hydronephrotic kidneys and may provide some reference to help clinical physician to explore a novel noninvasive approach to evaluate the single renal function.

The Analysis of Plant Location Effectiveness the Study of Sarir Gas Turbine 855 Mw Project Site at General Electric Company of Libya

The study presents a reporton Sarir Gas turbine industrial management especially for economical sustainable operation and proper element of plant management due to particularly design of an oil transportation system. It is found that the company is doing relative with some operational challenges and many people in Libya is rely on it and the influence of Government policies and programs on plant locations is quite helpful, particularly in planned economies area.

Catching Some Rays: Variable Generation Integration on the Island of Oahu

Starting in 2009, the Hawaii Natural Energy Institute, the Hawaiian Electric Company, and the General Electric Company, in collaboration with DOE, jointly developed and validated state-of-the-art power systems models of the Oahu and Maui electrical systems to study the operational impacts of increasing levels of wind and solar generation. These models were central to a series of coordinated, detailed technical studies which included the 2010 Hawaiian Islands Transmission Interconnection Studies (Stage I: Cable), the 2011 Oahu Wind Integration and Transmission Study (OWITS), the 2012 Hawaii Solar Integration Study (HSIS), and the 2013 Hawaiian Islands Interconnection Studies (Stage II: Grid Tie). This article focuses on key OWITS and HSIS findings for Oahu.

Putting the Bias in Skill-Biased Technological Change? A Relational Perspective on White-Collar Automation at General Electric

The skill-biased technological change (SBTC) theory of rising inequality rests on assumptions that are challenged by a relational perspective. This article develops a historical case study of the design and implementation of technologies to automate white-collar work at the General Electric Company (GE) starting in the 1950s in order to interrogate the assumptions on which the SBTC thesis rests. Executives at GE resisted framing computer technologies as automation and sought to neutralize the class-based implications of the term. Yet they actively pursued white-collar automation technologies designed to prevent the industrial relations of the heavily unionized manufacturing sector from being replicated in the growing service sector. A new conception of productivity that locates managers as the core productive workers of the firm is embedded in the company’s internal definition of white-collar automation as information handling, lending legitimacy to the changing distribution of earnings in the following decades. By embedding the history of white-collar workplace computers in an analysis of the labor relations and other business administration problems the technologies were designed to address, this article lends a critical perspective to the SBTC theory of rising inequality.

Applications of Stakeholder Theory in Information Systems and Technology

Abstract. Stakeholder theory has its origins in management literature. Preston (1999) traces the notion of stakeholders back to the great depression in the United States (1929-1941), when the General Electric company defined four major stakeholder groups - shareholders, employees, customers, and the general public. Stakeholder management has become an important tool to transfer ethics to management practice and strategy. Few management topics have generated more debate in recent decades than the underlying notion, the model and the theories surrounding stakeholders (Donaldson and Preston, 1995; Gibson, 2000; Wolfe and Putler, 2002; Friedman and Miles, 2006). The visual power of the stakeholder model and its high simplicity are seen as contributors to the success of the stakeholder concept (Fassin, 2008). An increasing interrelation is observed between the concepts of stakeholder theory, corporate responsibility, and business ethics (Valor, 2005; Garriga et al., 2004). The stakeholder approach in the organization integrates stakeholder relationships within a company’s resource base, industry setting, and socio-political arena into a single analytical framework (Susniene and Sargunas, 2009). Mumford (1979) is one of the early researchers in supporting the involvement of end-users as a component of effective information systems development and implementation, using essentially the stakeholder concept in this domain. It has been proved that end-users and managers are very important towards successful system implementation. As more interorganizational information systems are developed which usually involve strategic decisions, a yet wider range of stakeholders needs to be involved (Pouloudi, 1999). In these systems the attention may switch from end-users and focus on those parties that are external to the organization, but who can also be associated in decision making at a managerial or strategic level (Pouloudi and Whitely, 1997). One of the most thorough investigations of the stakeholder concept in information systems research that relates information systems stakeholders with implementation failure was made as an early work by Lyytinen and Hirschheim (1987, 1988). They argue that failure is conditional on the capability of information system to meet the expectations of different stakeholders - i.e. to say an information system may be considered successful by some stakeholder but a failure by others. The concept of stakeholder represents a progression from developer – and user – centered problems to organization-wide and inter organizational information system problems. This is a sign of maturity of information systems research to show how holistic representation of the parties involved in the more complex systems currently developed (Pouloudi, 1999). Stakeholder theory proposes an ethical use of stakeholder concept in Information systems as ethical considerations and professional conduct is a significant issue in information system. The stakeholder theory is extensively used in management in investigating organizational ambiance, strategic management, ethical concerns, business planning process, e-government, project management, environment management, etc. Recently stakeholders are also seen as means to more successful information and communication technologies and information system development and implementation issues. The paper presents stakeholder theory, its origin and applications in Information Systems (IS) field in the literature. The main objective of this research is to build up the knowledge body of stakeholder applications in information systems and technology areas.DOI: http://dx.doi.org/10.5755/j01.ee.24.3.4618

WE‐E‐103‐02: Past, Present and Future Roles of ROC Analysis in Medical Imaging and Quantitative Image Analysis

Receiver Operating Characteristic (ROC) analysis has been a mainstay of many research developments as well as various clinical studies/trials. It has provided medical physicists with a way to objectively measure how data are presented in an image, how people perceive those images, and how one can compare different observers or different imaging modalities with each other. ROC analysis plays an important role in both technology assessment and clinical decision‐making, especially as various aspects of imaging biomarkers and personalized medicine are evaluated. Over the past five years, on average, almost 40 papers/year that were published in MEDICAL PHYSICS utilized ROC analysis. The challenges and opportunities in ROC analysis research and in its application in various tasks are active areas, including expanding the mathematical formulation for multiple lesions per image, location‐based sensitivity, and evaluation without ground truth, as well as expanding its role in imaging biomarker validation, assessing response to therapy, theranostics, and image‐based phenotyping with genomics (image‐omics).Learning Objectives:1. Review the mathematical foundations and implementation of ROC analysis in basic research and clinical trials; and understand the role and limitations of ROC analysis in large scale clinical studies/trials2. Recognize advances in ROC analysis in order to incorporate multiple lesions per image, location‐based sensitivity, evaluation without ground truth, theranostics, and others3. Appreciate the evolving role of ROC analysis in the evaluation of imaging biomarkers and image‐based phenotypingResearch supported by NIH, DOE, and DOD.COI: Stockholder, Hologic, Inc Shareholder, Quantitative Insights, Inc Royalties, Hologic, Inc Royalties, General Electric Company Royalties, MEDIAN Technologies Royalties, Riverain Technologies, LLC Royalties, Mitsubishi Corporation Royalties, Toshiba Maryellen Giger Corporation Researcher, Koninklijke Philips Electronics NV Researcher, U‐Systems, Inc

Tuning of Power System Stabilizer (Unitrol D) in Benghazi North Power Plant

The use of power system stabilizers (PSSs) to damp power system swing mode of oscillations is of practical important. The authors purpose is to retune the power system stabilizer (PSS1A) parameters in Unitrol D produced by ABB– was installed in 1995 in Benghazi North Power Plants (BNPPs) at General Electricity Company of Libya (GECOL). Power systems are steadily growing with larger capacity, so the optimal values of the power system stabilizer (PSS1A) parameters should be retuned. A particle swarm optimization technique (PSO) is used to determine the parameters of the PSS off-line. The objective is to damp the local and inter-area modes of oscillations that occur following power system disturbances. The retuned power system stabilizer (PSS1A) can cope with large disturbance at different operating points and has an enhanced power system stability, The MATLAB package with SIMULINK is used for the design and simulations.

Pro: The value of randomized controlled studies in dialysis methods

INTRODUCTIONWillis R. Whitney, a chemist, who founded the General Elec-tric Company laboratory once said ‘Necessity is not themother of invention. Knowledge and experiment are itsparents’ [1]. Twardowski and Misra reject the primacy ofexperimentation. They wish us to abandon the necessity todemonstrate by rigorous randomized trials that longer dur-ation and/or more frequent is superior to intermittent dialysis.They argue that randomized controlled studies (RCTs) areinadequate as a research methodology in evaluating a dialysismethod citing limitations with each of the four RCTs—theNational Cooperative Dialysis Study [2], the HEMO study [3],the Frequent Hemodialysis Network (FHN) study [4] and theFHN Nocturnal trial [5]. Twardowski and Misra suggest that‘all progress in dialysis methods was made in research pre-sented in case reports, case control studies and other observa-tional studies. ‘and that’ four RCTs in hemodialysis did notprovide any useful data….observational studies allow clinicalresearch to represent the full breadth of treated patients andoffer tremendous power…’.The approach that Twardowski and Misra is questionable.We can hardly blame rigorous experimentation because ahandful of studies that have been performed so far do notsupport a belief, however strongly held the belief is. After allany given study may have asked the wrong question, or inad-vertently reached the wrong conclusion, or been null becauseof lack of power, or may have problems with study quality(for example, imbalances between the randomized groups oran excessive drop-out rate). Surely, this does not mean thatthe whole methodological approach embodied in RCTs iswrong? RCTs have value in the investigation of interventionslike the choice of dialysis methods, just as they are importantto other forms of human investigation.Twardowski and Misra acknowledge that RCTs representthe most rigorous method to determine whether a cause-and-effect relation exists between any treatment and an outcome.However, they understate the true advantage of RCTs overobservational studies. In the study of interventions, RCTs aresuperior to observational studies because RCTs are based onrandom allocation of subjects to two or more interventiongroups. The possibility of a systematic error is reducedbecause patient-related confounding factors are balancedacross different interventions. While skilled biostatisticiansand epidemiologists might try to attenuate the effect of con-founding, these attempts are generally imperfect and residualconfounding almost always exists. Besides, in RCTs, the inter-vention groups are treated identically, except for the exper-imental treatment. Subjects are analyzed within the group towhich they were allocated, irrespective of whether theyexperience the intended intervention or not (intention totreat analysis) further reducing the chance of bias.Knowledge and experimentation are the founding prin-ciples of evidence-based medicine. The randomized trial rep-resents the most rigorous method to get to the truth ofwhether an intervention causes an outcome. We shouldembrace RCTs not abandon them. RCTs are essential, becauseas Chertow has written [6] ‘Wishing Don’t Make it So’.Evaluating non-randomized studies on dialysismethods: all that glitters is not goldTwardowski and Misra emphasize the importance of non-randomized studies in determining the optimal duration andfrequency of dialysis. These non-randomized studies cover abroad spectrum: case reports, case series, historical controlledtrials and registry data. Collectively, the observational experi-ence has laid the foundation for performing randomizedtrials but is not a substitute.Consider one of the studies cited by Twardowski and Misrain their article to support the superiority of more frequent and/or longer dialysis. This was a study performed by Twardowskibetween 1969 and 1973 and exemplified a ‘before and afterdesign’ [7]. Fourteen dialysis patients were enrolled and after a

Photoneutron contamination from an 18 MV Saturne medical linear accelerator in the treatment room

Dose escalation with high-energy X rays of medical linear accelerators (linacs) in radiotherapy offers several distinct advantages over the lower energy photons. However, owing to photoneutron reactions, interaction of high-energy photons (>8 MV) with various high-Z nuclei of the materials in the linac head components produces unavoidable neutrons. The aim of this study was to evaluate the photoneutron dose equivalent per unit therapeutic X-ray dose of 18 MV, GE Saturne 20 linac in the treatment room using Monte Carlo (MC) MCNP linac head full simulation as well as thermoluminescence dosemeter measurements. This machine is one of the old linac models manufactured by General Electric Company; however, it is widely used in the developing countries because of low cost and simple maintenance for radiotherapy applications. The results showed a significant photoneutron dose from Saturne 20 linac head components especially at distances near the linac head (<150 cm). Results of this work could be used in several applications, especially designing bunker and entrance door shielding against neutrons produced by photoneutron reactions in GE Saturne 20. However, a detailed cost optimisation for a specific room would require a dedicated calculation.

Effects of Subanesthetic Dose of Nitrous Oxide on Cerebral Blood Flow and Metabolism

Nitrous oxide, in a concentration of 50% or more, is a known cerebral vasodilator. This study investigated whether a lower dose (30%) of nitrous oxide would also increase cerebral blood flow. In addition, the authors wished to study whether the increase in cerebral blood flow was accompanied by an increase in cerebral metabolism. Multimodal Magnetic Resonance Imaging at 3T was performed, and data were obtained in 17 healthy volunteers during three inhalation conditions: medical air, oxygen-enriched medical air (40% oxygen), and 30% nitrous oxide with oxygen-enriched medical air (40% oxygen). Arterial spin labeling was used to derive the primary tissue specific hemodynamic outcomes: cerebral blood flow, arterial blood volume and arterial transit times. Magnetic Resonance Susceptometry and proton Magnetic Resonance Spectroscopy were used for secondary metabolic outcomes: venous oxygenation, oxygen extraction fraction, cerebral metabolic oxygen rate and prefrontal metabolites. Nitrous oxide in 40% oxygen, but not 40% oxygen alone, significantly increased gray matter cerebral blood flow (22%; P < 0.05) and arterial blood volume (41%; P < 0.05). Venous oxygenation increased in both oxygen and nitrous oxide conditions. Compared with medical air inhalation, nitrous oxide condition caused a significantly larger decrease in oxygen extraction fraction than 40% oxygen alone (mean [SD] 11.3 [5.6]% vs. 8.3 [5.9]% P < 0.05), while global cerebral metabolic rate and prefrontal metabolites remained unchanged. This study demonstrates that 30% nitrous oxide in oxygen-enriched air (40% oxygen) significantly increases cerebral perfusion, and reduces oxygen extraction fraction, reflecting a strong arterial vasodilatory effect without associated increases in metabolism.

Intraoperative plateau pressure measurement using modern anesthesia machine ventilators

Monitoring respiratory system mechanics is vital to guide safe and effective ventilator management. Transalveolar pressure (tAp) is the driving force of alveolar distension, which allows for effective respiration; however, overdistension may lead to inflammation and subsequent destruction of alveoli. Unfortunately, there is no practical way to measure tAp directly; hence, surrogate measures are often used. Peak airway pressure (PAP), commonly monitored in patients undergoing general anesthesia, consists of static and dynamic components. Volume-preset ventilation allows determination of the respiratory system mechanics. In a muscle-relaxed patient, PAP consists of two components, i.e., the dynamic pressure to drive gas across the resistance (Pres) of the bronchial tree and the static pressure to expand the alveoli against the elastic recoil of the lungs and chest wall (Plateau pressure, [Pplat]), which is more reflective of tAp than PAP. Plateau pressure can be displayed easily on the new generation of anesthesia machine ventilators by inserting an end-inspiratory pause of 0.5-1 sec. Calculating the difference in airway pressure during flow and no-flow states allows the calculation of airway resistance (Pres = PAP Pplat). Diagnostic and therapeutic information can be extracted by distinguishing components of PAP. This information can help the anesthesia provider to narrow the differential diagnosis of high PAP to help solve oxygenation/ventilation issues and tailor treatment. For example, elevated Pres at constant flow may indicate bronchospasm or endotracheal tube obstruction (Figure). Conversely, falling Pres may correspond with a response to bronchodilators. Elevated Pplat indicates excessive tidal volume or decreased lung and/or chest wall compliance (e.g., pulmonary edema, acute lung injury, or abdominal distension). Positive pressure ventilation may cause or exacerbate lung injury due to an increase in lung stretching which is best assessed by the transpulmonary pressure or the tAp. Separation of lungs from chest wall compliance requires an esophageal pressure measurement to approximate pleural pressure. Due to the technical and accuracy limitations, esophageal manometry is not widely used, and Pplat is used as a surrogate to guide titration of mechanical ventilation. As a lung protective ventilation strategy, it is recommended that Pplat be maintained B 30 cm H2O to prevent alveolar overdistension and barotrauma, especially in acute lung injury and during one-lung ventilation. Whenever chest compliance is reduced, the stiff chest contributes substantially to Pplat. This should be taken into consideration when assessing lung stretch, as higher Pplat may still be safe due to the limitation of alveolar distension by the chest wall. We present two examples of procedures to acquire Pplat in the operating room using two popular anesthesia machines. For the GE S/5 Aespire SmartVent (General Electric Company, Madison, WI, USA) (Figure), select setup/calibration from the main menu (Figure, upper panel); then change the inspiratory pause from 0 to 30-60% to achieve a pause of 0.5-1 sec, and Pplat will be displayed (Figure, lower panel). With a respiratory rate of 8 breaths min and inspiratory:expiratory (I:E) ratio 1:2, M. A. Helwani, MD (&) Washington University School of Medicine, St. Louis, MO, USA e-mail: helwanim@anest.wustl.edu

NASA Environmentally Responsible Aviation Project Develops Next-Generation Low-Emissions Combustor Technologies (Phase I)

NASA’s Environmentally Responsible Aviation (ERA) Project is working with industry to develop the fuel flexible combustor technologies for a new generation of low-emissions engine targeted for the 2020 timeframe. These new combustors will reduce Nitrogen Oxide (NOx) emissions to half of current state-of-the-art (SOA) combustors, while simultaneously reducing noise and fuel burn. The purpose of the low NOx fuel-flexible combustor research is to advance the Technology Readiness Level (TRL) and Integration Readiness Level (IRL) of a low NOx, fuel flexible combustor to the point where it can be integrated in the next generation of aircraft. To reduce project risk and optimize research benefit NASA chose to found two Phase 1 contracts. The first Phase 1 contracts went to engine manufactures and were awarded to: General Electric Company, and Pratt & Whitney Company. The second Phase 1 contracts went to fuel injector manufactures Goodrich Corporation, Parker Hannifin Corporation, and Woodward Fuel System Technology. In 2012, two sector combustors were tested at NASA’s ASCR. The results indicated 75% NOx emission reduction below the 2004 CAEP/6 regulation level.

The application of linear programming by the General Electric Company to efficiently allocate routes to trucking companies

The appliance and lighting group of the General Electric (GE) Company allocates its shipping truckload to 17 different trucking companies over 701 different routes from one of its nine terminals. A sequence of several linear programming models was developed to help the management of the appliance and lighting division develop an optimal allocation. Two user-friendly interfaces were also developed to aid GE management in the use of one of the models. The tool is being used at GE and significant savings (approximately 15.5% of shipping costs) are possible with the optimal truckload allocation solution provided by the model.

Determination of trace metals in air of Chittagong city-Bangladesh

Air pollution problem is severe in the urban areas caused by both mobile as well as stationary sources. Mainly the two-stroke and diesel-run vehicles cause the severity of the problem by emitting highly contaminated exhausts. Considering severity of the problem, current study was undertaken to measure the air pollutants level in air of Chittagong city, Bangladesh. The heavy metals Zn, Pb, Mn, Cd, Cu and Co in suspended particulate matter (SPM) were determined at different locations of Chittagong city. The sampling locations were selected to reflect different influences from industrial and mobile sources in the highly populated center part of Chittagong city. Samplings were done during October and November 2008 from different areas of the metropolitan city of Chittagong city (Newmarket, Bahaddarhat, Nasirabad, General Electric Company (G.E.C.) Circle and Director’s Office of Department of Environment, Bangladesh). High volume sampler was used for the determination of SPM and the different metal concentrations were measured by atomic absorption spectrophotometer (AAS). The average results of particulate matters and trace metals have been compared to national and international standards. The value of SPM in air of Chittagong city is higher than that of Threshold Limit Value (TLV) recommended by World Health Organization (WHO), Environmental Protection Agency (EPA), USA and Department of Environment (DoE), Bangladesh. The metal concentrations of ambient air collected at different locations in Chittagong city is exceeded the threshold limit values and as a result the air of Chittagong city is considered polluted. Therefore, it is suggested that Government of Bangladesh should take proper steps to control the air pollution of Chittagong city.