Experimental Assessment of the Emissions Control Potential of a Rich/Quench/ Lean Combustor for High Speed Civil Transport Aircraft Engines

NASA Technical Reports Server (NTRS)

Tacina, Robert R. (Technical Monitor); Rosfjord, T. J.; Padget, F. C.

2001-01-01

In support of Pratt & Whitney efforts to define the Rich burn/Quick mix/Lean burn (RQL) combustor for the High Speed Civil Transport (HSCT) aircraft engine, UTRC conducted a flametube-scale study of the RQL concept. Extensive combustor testing was performed at the Supersonic Cruise (SSC) condition of an HSCT engine cycle. Data obtained from probe traverses near the exit of the mixing section confirmed that the mixing section was the critical component in controlling combustor emissions. Circular-hole configurations, which produced rapidly-, highly-penetrating jets, were most effective in limiting NO(x). The spatial profiles of NO(x) and CO at the mixer exit were not directly interpretable using a simple flow model based on jet penetration, and a greater understanding of the flow and chemical processes in this section are required to optimize it. Neither the rich-combustor equivalence ratio nor its residence time was a direct contributor to the exit NO(x). Based on this study, it was also concluded that: (1) While NO(x) formation in both the mixing section and the lean combustor contribute to the overall emission, the NOx formation in the mixing section dominates. The gas composition exiting the rich combustor can be reasonably represented by the equilibrium composition corresponding to the rich combustor operating condition. Negligible NO(x) exits the rich combustor. (2) At the SSC condition, the oxidation processes occurring in the mixing section consume 99 percent of the CO exiting the rich combustor. Soot formed in the rich combustor is also highly oxidized, with combustor exit SAE Smoke Number <3. (3) Mixing section configurations which demonstrated enhanced emissions control at SSC also performed better at part-power conditions. Data from mixer exit traverses reflected the expected mixing behavior for off-design jet to crossflow momentum-flux ratios. (4) Low power operating conditions require that the RQL combustor operate as a lean-lean combustor to achieve low CO and high efficiency. (5) An RQL combustor can achieve the emissions goal of EINO(x) = 5 at the Supersonic Cruise operating condition for an HSCT engine.

A three-dimensional algebraic grid generation scheme for gas turbine combustors with inclined slots

NASA Technical Reports Server (NTRS)

Yang, S. L.; Cline, M. C.; Chen, R.; Chang, Y. L.

1993-01-01

A 3D algebraic grid generation scheme is presented for generating the grid points inside gas turbine combustors with inclined slots. The scheme is based on the 2D transfinite interpolation method. Since the scheme is a 2D approach, it is very efficient and can easily be extended to gas turbine combustors with either dilution hole or slot configurations. To demonstrate the feasibility and the usefulness of the technique, a numerical study of the quick-quench/lean-combustion (QQ/LC) zones of a staged turbine combustor is given. Preliminary results illustrate some of the major features of the flow and temperature fields in the QQ/LC zones. Formation of co- and counter-rotating bulk flow and shape temperature fields can be observed clearly, and the resulting patterns are consistent with experimental observations typical of the confined slanted jet-in-cross flow. Numerical solutions show the method to be an efficient and reliable tool for generating computational grids for analyzing gas turbine combustors with slanted slots.

6th Annual National Small Business Conference

DTIC Science & Technology

2009-06-03

Extension Partnership – MIT Lean Advancement Initiative – Customers • Lean Tools – Value Stream Mapping – Kaizen Events Center for Management...Blue denotes kaizen events Most suppliers did not have in-house lean capability therefore the OEM and customer facilitated the events 36 Center for...Management & Economic Research 37 Kaizen Events • Kaizen is the process of: – Identifying & eliminating waste – as quickly as possible – at the

LHC magnet quench protection system

NASA Astrophysics Data System (ADS)

Coull, L.; Hagedorn, D.; Remondino, V.; Rodriguez-Mateos, F.

1994-07-01

The quench protection system for the superconducting magnets of the CERN Large Hadron Collider (LHC) is described. The system is based on the so called 'cold diode' concept. In a group of series connected magnets if one magnet quenches then the magnetic energy of all the magnets will be dissipated in the quenched magnet so destroying it. This is avoided by by-passing the quenched magnet and then rapidly de-exciting the unquenched magnets. For the LHC machine it is foreseen to use silicon diodes situated inside the cryostat as by-pass elements - so called 'cold diodes'. The diodes are exposed to some 50 kGray of radiation during a 10 year operation life-time. The high energy density of the LHC magnets (500 kJ/m) coupled with the relatively slow propagation speed of a 'natural' quench (10 to 20 m/s) can lead to excessive heating of the zone where the quench started and to high internal voltages. It is therefore necessary to detect quickly the incipient quench and fire strip heaters which spread the quench out more quickly over a large volume of the magnet. After a quench the magnet chain must be de-excited rapidly to avoid spreading the quench to other magnets and over-heating the by-pass diode. This is done by switching high-power energy-dump resistors in series with the magnets. The LHC main ring magnet will be divided into 16 electrically separated units which has important advantages.

Understanding CO2 decomposition by thermal plasma with supersonic expansion quench

NASA Astrophysics Data System (ADS)

Tao, YANG; Jun, SHEN; Tangchun, RAN; Jiao, LI; Pan, CHEN; Yongxiang, YIN

2018-04-01

CO2 pyrolysis by thermal plasma was investigated, and a high conversion rate of 33% and energy efficiency of 17% were obtained. The high performance benefited from a novel quenching method, which synergizes the converging nozzle and cooling tube. To understand the synergy effect, a computational fluid dynamics simulation was carried out. A quick quenching rate of 107 K s‑1 could be expected when the pyrolysis gas temperature decreased from more than 3000 to 1000 K. According to the simulation results, the quenching mechanism was discussed as follows: first, the compressible fluid was adiabatically expanded in the converging nozzle and accelerated to sonic speed, and parts of the heat energy converted to convective kinetic energy; second, the sonic fluid jet into the cooling tube formed a strong eddy, which greatly enhanced the heat transfer between the inverse-flowing fluid and cooling tube. These two mechanisms ensure a quick quenching to prevent the reverse reaction of CO2 pyrolysis gas when it flows out from the thermal plasma reactor.

Effect of vane twist on the performance of dome swirlers for gas turbine airblast atomizers

NASA Technical Reports Server (NTRS)

Micklow, Gerald J.; Dogra, Anju S.; Nguyen, H. Lee

1990-01-01

For advanced gas turbine engines, two combustor systems, the lean premixed/prevaporized (LPP) and the rich burn/quick quench/lean burn (RQL) offer great potential for reducing NO(x) emissions. An important consideration for either concept is the development of an advanced fuel injection system that will provide a stable, efficient, and very uniform combustion system over a wide operating range. High-shear airblast fuel injectors for gas turbine combustors have exhibited superior atomization and mixing compared with pressure-atomizing fuel injectors. This improved mixing has lowered NO(x) emissions and the pattern factor, and has enabled combustors to alternate fuels while maintaining a stable, efficient combustion system. The performance of high-shear airblast fuel injectors is highly dependent on the design of the dome swirl vanes. The type of swirl vanes most widely used in gas turbine combustors are usually flat for ease of manufacture, but vanes with curvature will, in general, give superior aerodynamic performance. The design and performance of high-turning, low-loss curved dome swirl vanes with twist along the span are investigated. The twist induces a secondary vortex flow pattern which will improve the atomization of the fuel, thereby producing a more uniform fuel-air distribution. This uniform distribution will increase combustion efficiency while lowering NO(x) emissions. A systematic swirl vane design system is presented based on one-, two-, and three-dimensional flowfield calculations, with variations in vane-turning angle, rate of turning, vane solidity, and vane twist as design parameters.

Effect of vane twist on the performance of dome swirlers for gas turbine airblast atomizers

NASA Astrophysics Data System (ADS)

Micklow, Gerald J.; Dogra, Anju S.; Nguyen, H. Lee

1990-07-01

For advanced gas turbine engines, two combustor systems, the lean premixed/prevaporized (LPP) and the rich burn/quick quench/lean burn (RQL) offer great potential for reducing NO(x) emissions. An important consideration for either concept is the development of an advanced fuel injection system that will provide a stable, efficient, and very uniform combustion system over a wide operating range. High-shear airblast fuel injectors for gas turbine combustors have exhibited superior atomization and mixing compared with pressure-atomizing fuel injectors. This improved mixing has lowered NO(x) emissions and the pattern factor, and has enabled combustors to alternate fuels while maintaining a stable, efficient combustion system. The performance of high-shear airblast fuel injectors is highly dependent on the design of the dome swirl vanes. The type of swirl vanes most widely used in gas turbine combustors are usually flat for ease of manufacture, but vanes with curvature will, in general, give superior aerodynamic performance. The design and performance of high-turning, low-loss curved dome swirl vanes with twist along the span are investigated. The twist induces a secondary vortex flow pattern which will improve the atomization of the fuel, thereby producing a more uniform fuel-air distribution. This uniform distribution will increase combustion efficiency while lowering NO(x) emissions. A systematic swirl vane design system is presented based on one-, two-, and three-dimensional flowfield calculations, with variations in vane-turning angle, rate of turning, vane solidity, and vane twist as design parameters.

Effect of vane twist on the performance of dome swirlers for gas turbine airblast atomizers

NASA Astrophysics Data System (ADS)

Micklow, Gerald J.; Dogra, Anju S.; Nguyen, H. Lee

1990-06-01

For advanced gas turbine engines, two combustor systems, the lean premixed/prevaporized (LPP) and the rich burn/quick quench/lean burn (RQL) offer great potential for reducing NO(x) emissions. An important consideration for either concept is the development of an advanced fuel injection system that will provide a stable, efficient, and very uniform combustion system over a wide operating range. High-shear airblast fuel injectors for gas turbine combustors have exhibited superior atomization and mixing compared with pressure-atomizing fuel injectors. This improved mixing has lowered NO(x) emissions and the pattern factor, and has enabled combustors to alternate fuels while maintaining a stable, efficient combustion system. The performance of high-shear airblast fuel injectors is highly dependent on the design of the dome swirl vanes. The type of swirl vanes most widely used in gas turbine combustors are usually flat for ease of manufacture, but vanes with curvature will, in general, give superior aerodynamic performance. The design and performance of high-turning, low-loss curved dome swirl vanes with twist along the span are investigated. The twist induces a secondary vortex flow pattern which will improve the atomization of the fuel, thereby producing a more uniform fuel-air distribution. This uniform distribution will increase combustion efficiency while lowering NO(x) emissions. A systematic swirl vane design system is presented based on one-, two-, and three-dimensional flowfield calculations, with variations in vane-turning angle, rate of turning, vane solidity, and vane twist as design parameters.

Mixing of Pure Air Jets with a Reacting Fuel-Rich Crossflow

NASA Technical Reports Server (NTRS)

Leong, M. Y.; Samuelsen, G. S.; Holdeman, J. D.

1997-01-01

Jets in a crossflow play an integral role in practical combustion systems such as can and annular gas turbine combustors in conventional systems, and the Rich-burn/Quick-mix/Lean-burn (RQL) combustor utilized in stationary applications and proposed for advanced subsonic and supersonic transports. The success of the RQL combustor rests with the performance of the quick-mixing section that bridges the rich and lean zones. The mixing of jet air with a rich crossflow to bring the reaction to completion in the lean zone must be performed rapidly and thoroughly in order to decrease the extent of near-stoichiometric fluid pocket formation. Fluid pockets at near-stoichiometric equivalence ratios are undesirable because the high temperatures attained accelerate pollutant formation kinetics associated with nitric oxide (NO). The present study develops a model experiment designed to reveal the processes that occur when jet air is introduced into hot effluent emanating from a fuel-rich reaction zone.

Rich burn combustor technology at Pratt and Whitney

NASA Technical Reports Server (NTRS)

Lohmann, Robert P.; Rosfjord, T. J.

1992-01-01

The topics covered include the following: near term objectives; rich burn quick quench combustor (RBQC); RBQC critical technology areas; cylindrical RBQQ combustor rig; modular RBQQ combustor; cylindrical rig objectives; quench zone mixing; noneffusive cooled liner; variable geometry requirements; and sector combustor rig.

Lean oncology: a new model for oncologists.

PubMed

Montesarchio, Vincenzo; Grimaldi, Antonio Maria; Fox, Bernard A; Rea, Antonio; Marincola, Francesco M; Ascierto, Paolo A

2012-04-25

The history of the term Lean is relatively recent and originates from the Toyota Production System (TPS). The term "Lean" means "thin", which refers to a mental process, operational, productive, no-frills, quick but not hasty, consequential to the previous event. The Lean process flows seamlessly into the result, eliminates unnecessary complications to the effect, prevents unnecessary equipment processes. The idea is to 'do more with less', like using the (few) available resources in the most productive way possible, through the elimination of all types of waste that inevitably accompanies every stage of a production process. Lean management is primarily a management philosophy, a system of values and behaviors that goes beyond the mere application of the instrument and that, once internalized, will form the nucleus of the corporate culture. "Lean Oncology" is a term coined to identify a methodology of care and treatment to cancer patients, consisting on process simplification, streamlining of the organizational and routes of drug treatment, detection and elimination of waste. Its main objective is the centrality of the patient.

NO{sub x}-abatement potential of lean-premixed GT combustors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sattelmayer, T.; Polifke, W.; Winkler, D.

1998-01-01

The influence of the structure of perfectly premixed flames on NO{sub x} formation is investigated theoretically. Since a network of reaction kinetics modules and model flames is used for this purpose, the results obtained are independent of specific burner geometries. Calculations are presented for a mixture temperature of 630 K, an adiabatic flame temperature of 1840 K, and 1 and 15 bars combustor pressure. In particular, the following effects are studied separately from each other: molecular diffusion of temperature and species, flame strain, local quench in highly strained flames and subsequent reignition, turbulent diffusion (no preferential diffusion), and small scalemore » mixing (stirring) in the flame front. Either no relevant influence or an increase in NO{sub x} burners is to avoid excessive turbulent stirring in the flame front. Turbulent flames that exhibit locally and instantaneously near laminar structures (flamelets) appear to be optimal. Using the same methodology, the scope of the investigation is extended to lean-lean staging, since a higher NO{sub x}-abatement potential can be expected in principle. As long as the chemical reactions of the second stage take place in the boundary between the fresh mixture of the second stage and the combustion products from upstream, no advantage can be expected from lean-lean staging. Only if the preliminary burner exhibits much poorer mixing than the second stage can lean-lean staging be beneficial. In contrast, if full mixing between the two stages prior to afterburning can be achieved (lean-mix-lean technique), the combustor outlet temperature can in principle be increased somewhat without NO penalty.« less

Emission measurements for a lean premixed propane/air system at pressures up to 30 atmospheres

NASA Technical Reports Server (NTRS)

Roffe, G.; Venkataramani, K. S.

1978-01-01

The emissions of a lean premixed system of propane/air were measured in a flametube apparatus. Tests were conducted at inlet temperatures of 600K and 800K and pressures of 10 atm and 30 atm over a range of equivalence ratios. The data obtained were combined with previous data taken in the same apparatus to correlate nitrogen oxide emissions with operating conditions. Sampling probe design was found to have a pronounced effect on measured CO levels but did not influence measurements. The most effective probe tested was one which combined thermal and pressure quenching of the gas sample.

Acoustical-Levitation Chamber for Metallurgy

NASA Technical Reports Server (NTRS)

Barmatz, M. B.; Trinh, E.; Wang, T. G.; Elleman, D. D.; Jacobi, N.

1983-01-01

Sample moved to different positions for heating and quenching. Acoustical levitation chamber selectively excited in fundamental and second-harmonic longitudinal modes to hold sample at one of three stable postions: A, B, or C. Levitated object quickly moved from one of these positions to another by changing modes. Object rapidly quenched at A or C after heating in furnace region at B.

Performance of a Model Rich Burn-quick Mix-lean Burn Combustor at Elevated Temperature and Pressure

NASA Technical Reports Server (NTRS)

Peterson, Christopher O.; Sowa, William A.; Samuelsen, G. S.

2002-01-01

As interest in pollutant emission from stationary and aero-engine gas turbines increases, combustor engineers must consider various configurations. One configuration of increasing interest is the staged, rich burn - quick mix - lean burn (RQL) combustor. This report summarizes an investigation conducted in a recently developed high pressure gas turbine combustor facility. The model RQL combustor was plenum fed and modular in design. The fuel used for this study is Jet-A which was injected from a simplex atomizer. Emission (CO2, CO, O2, UHC, NOx) measurements were obtained using a stationary exit plane water-cooled probe and a traversing water-cooled probe which sampled from the rich zone exit and the lean zone entrance. The RQL combustor was operated at inlet temperatures ranging from 367 to 700 K, pressures ranging from 200 to 1000 kPa, and combustor reference velocities ranging from 10 to 20 m/s. Variations were also made in the rich zone and lean zone equivalence ratios. Several significant trends were observed. NOx production increased with reaction temperature, lean zone equivalence ratio and residence time and decreased with increased rich zone equivalence ratio. NOx production in the model RQL combustor increased to the 0.4 power with increased pressure. This correlation, compared to those obtained for non-staged combustors (0.5 to 0.7), suggests a reduced dependence on NOx on pressure for staged combustors. Emissions profiles suggest that rich zone mixing is not uniform and that the rich zone contributes on the order of 16 percent to the total NOx produced.

A fluorescence quenching test for the detection of flavonoid transformation.

PubMed

Schoefer, L; Braune, A; Blaut, M

2001-11-13

A novel fluorescence quenching test for the detection of flavonoid degradation by microorganisms was developed. The test is based on the ability of the flavonoids to quench the fluorescence of 1,6-diphenyl-1,3,5-hexatriene (DPH). Several members of the anthocyanidins, flavones, isoflavones, flavonols, flavanones, dihydroflavanones, chalcones, dihydrochalcones and catechins were tested with regard to their quenching properties. The anthocyanidins were the most potent quenchers of DPH fluorescence, while the flavanones, dihydroflavanones and dihydrochalcones, quenched the fluorescence only weakly. The catechins had no visible impact on DPH fluorescence. The developed test allows a quick and easy differentiation between flavonoid-degrading and flavonoid-non-degrading bacteria. The investigation of individual reactions of flavonoid transformation with the developed test system is also possible.

Design of Ski Boots for Alpine Ski Racing Based on Leg Frame of the Skier

NASA Astrophysics Data System (ADS)

Suzuki, Soichiro; Hayashi, Sueyoshi

A ski boot is important to make progress in ski turning technique as an interface between a skier and a ski. Especially in alpine ski races, suitability of design of the boots for racers becomes more important to achieve accurate and quick lean of the leg in ski turns. This study is aimed at building a new design concept of a ski boot that can improve the results of alpine ski races. In this paper, new design of an upper shell of a ski boot that was adjusted to the features of the frame of alpine ski racers was experimentally examined. As a result, it was demonstrated that a front and a rear part of the upper shell of a ski boot should be separately adjusted to the length of a shank of each player for well-balanced quick lean of the leg in the ski turn. Finally, the effect of new design of an upper shell was examined in giant slalom and slalom tests by Japanese alpine ski racers of the first rank. Consequently, the results showed that lean angle during turns was increased and finish time was shortened when the skiers wore the newly designed boots.

Evaluation of concepts for controlling exhaust emissions from minimally processed petroleum and synthetic fuels

NASA Technical Reports Server (NTRS)

Russell, P. L.; Beal, G. W.; Sederquist, R. A.; Shultz, D.

1981-01-01

Rich-lean combustor concepts designed to enhance rich combustion chemistry and increase combustor flexibility for NO(x) reduction with minimally processed fuels are examined. Processes such as rich product recirculation in the rich chamber, rich-lean annihilation, and graduated air addition or staged rich combustion to release bound nitrogen in steps of reduced equivalence ratio are discussed. Variations to the baseline rapid quench section are considered, and the effect of residence time in the rich zone is investigated. The feasibility of using uncooled non-metallic materials for the rich zone combustion construction is also addressed. The preliminary results indicate that rich primary zone staged combustion provides environmentally acceptable operation with residual and/or synthetic coal-derived liquid fuels

Predicting broadband noise from a stator vane of a gas turbine engine

NASA Technical Reports Server (NTRS)

Hanson, Donald B. (Inventor)

2002-01-01

A computer-implemented model of fan section of a gas turbine engine accounts for the turbulence in the gas flow emanating from the rotor assembly and impinging upon an inlet to the stator vane cascade. The model allows for user-input variations in the sweep and/or lean angles for the stator vanes. The model determines the resulting acoustic response of the fan section as a function of the turbulence and the lean and/or sweep angles of the vanes. The model may be embodied in software that is rapidly executed in a computer. This way, an optimum arrangement in terms of fan noise reduction is quickly determined for the stator vane lean and sweep physical positioning in the fan section of a gas turbine engine.

Large Engine Technology Program. Task 21: Rich Burn Liner for Near Term Experimental Evaluations

NASA Technical Reports Server (NTRS)

Hautman, D. J.; Padget, F. C.; Kwoka, D.; Siskind, K. S.; Lohmann, R. P.

2005-01-01

The objective of the task reported herein, which was conducted as part of the NASA sponsored Large Engine Technology program, was to define and evaluate a near-term rich-zone liner construction based on currently available materials and fabrication processes for a Rich-Quench-Lean combustor. This liner must be capable of operation at the temperatures and pressures of simulated HSCT flight conditions but only needs sufficient durability for limited duration testing in combustor rigs and demonstrator engines in the near future. This must be achieved at realistic cooling airflow rates since the approach must not compromise the emissions, performance, and operability of the test combustors, relative to the product engine goals. The effort was initiated with an analytical screening of three different liner construction concepts. These included a full cylinder metallic liner and one with multiple segments of monolithic ceramic, both of which incorporated convective cooling on the external surface using combustor airflow that bypassed the rich zone. The third approach was a metallic platelet construction with internal convective cooling. These three metal liner/jacket combinations were tested in a modified version of an existing Rich-Quench-Lean combustor rig to obtain data for heat transfer model refinement and durability verification.

Fluorescent Metal-Organic Framework (MOF) as a Highly Sensitive and Quickly Responsive Chemical Sensor for the Detection of Antibiotics in Simulated Wastewater.

PubMed

Zhu, Xian-Dong; Zhang, Kun; Wang, Yu; Long, Wei-Wei; Sa, Rong-Jian; Liu, Tian-Fu; Lü, Jian

2018-02-05

A Zn(II)-based fluorescent metal-organic framework (MOF) was synthesized and applied as a highly sensitive and quickly responsive chemical sensor for antibiotic detection in simulated wastewater. The fluorescent chemical sensor, denoted FCS-1, exhibited enhanced fluorescence derived from its highly ordered, 3D MOF structure as well as excellent water stability in the practical pH range of simulated antibiotic wastewater (pH = 3.0-9.0). Remarkably, FCS-1 was able to effectively detect a series of sulfonamide antibiotics via photoinduced electron transfer that caused detectable fluorescence quenching, with fairly low detection limits. Two influences impacting measurements related to wastewater treatment and water quality monitoring, the presence of heavy-metal ions and the pH of solutions, were studied in terms of fluorescence quenching, which was nearly unaffected in sulfonamide-antibiotic detection. Additionally, the effective detection of sulfonamide antibiotics was rationalized by the theoretical computation of the energy bands of sulfonamide antibiotics, which revealed a good match between the energy bands of FCS-1 and sulfonamide antibiotics, in connection with fluorescence quenching in this system.

Quench simulation results for a 12-T twin-aperture dipole magnet

NASA Astrophysics Data System (ADS)

Cheng, Da; Salmi, Tiina; Xu, Qingjin; Peng, Quanling; Wang, Chengtao; Wang, Yingzhe; Kong, Ershuai; Zhang, Kai

2018-06-01

A 12-T twin-aperture subscale dipole magnet is being developed for SPPC pre-study at the Institute of High Energy Physics (IHEP). The magnet is comprised of 6 double-pancake coils which include 2 Nb3Sn coils and 4 NbTi coils. As the stored energy of the magnet is 0.452 MJ and the operation margin is only about 20% at 4.2 K, a quick and effective quench protection system is necessary during the test of this high field magnet. For the design of the quench protection system, attention was not only paid to the hotspot temperature and terminal voltage, but also the temperature gradient during the quench process due to the poor mechanical characteristics of the Nb3Sn cables. With the adiabatic analysis, numerical simulation and the finite element simulation, an optimized protection method is adopted, which contains a dump resistor and quench heaters. In this paper, the results of adiabatic analysis and quench simulation, such as current decay, hot-spot temperature and terminal voltage are presented in details.

Sector Tests of a Low-NO(sub x), Lean, Direct- Injection, Multipoint Integrated Module Combustor Concept Conducted

NASA Technical Reports Server (NTRS)

Tacina, Robert R.; Wey, Chang-Lie; Laing, Peter; Mansour, Adel

2002-01-01

The low-emissions combustor development described is directed toward advanced high pressure aircraft gas-turbine applications. The emphasis of this research is to reduce nitrogen oxides (NOx) at high-power conditions and to maintain carbon monoxide and unburned hydrocarbons at their current low levels at low power conditions. Low-NOx combustors can be classified into rich-burn and lean-burn concepts. Lean-burn combustors can be further classified into lean-premixed-prevaporized (LPP) and lean direct injection (LDI) concepts. In both concepts, all the combustor air, except for liner cooling flow, enters through the combustor dome so that the combustion occurs at the lowest possible flame temperature. The LPP concept has been shown to have the lowest NOx emissions, but for advanced high-pressure-ratio engines, the possibility of autoignition or flashback precludes its use. LDI differs from LPP in that the fuel is injected directly into the flame zone, and thus, it does not have the potential for autoignition or flashback and should have greater stability. However, since it is not premixed and prevaporized, good atomization is necessary and the fuel must be mixed quickly and uniformly so that flame temperatures are low and NOx formation levels are comparable to those of LPP. The LDI concept described is a multipoint fuel injection/multiburning zone concept. Each of the multiple fuel injectors has an air swirler associated with it to provide quick mixing and a small recirculation zone for burning. The multipoint fuel injection provides quick, uniform mixing and the small multiburning zones provide for reduced burning residence time, resulting in low NOx formation. An integrated-module approach was used for the construction where chemically etched laminates, diffusion bonded together, combine the fuel injectors, air swirlers, and fuel manifold into a single element. The multipoint concept combustor was demonstrated in a 15 sector test. The configuration tested had 36 fuel injectors and fuel-air mixers that replaced two fuel injectors in a conventional dual-annular combustor. During tests, inlet temperatures were up to 870 K and inlet pressures were up to 5400 kPa. A correlation was developed that related the NOx emissions with the inlet temperature, inlet pressure, fuel-air ratio, and pressure drop. At low-power conditions, fuel staging was used so that high combustion efficiency was obtained with only one-fourth of the fuel injectors flowing. The test facility had optical access, and visual images showed the flame to be very short, approximately 25 mm long.

Large Engine Technology Program. Task 22: Variable Geometry Concepts for Rich-Quench-Lean Combustors

NASA Technical Reports Server (NTRS)

Tacina, Robert R. (Technical Monitor); Cohen, J. M.; Padget, F. C.; Kwoka, D.; Wang, Q.; Lohmann, R. P.

2005-01-01

The objective of the task reported herein was to define, evaluate, and optimize variable geometry concepts suitable for use with a Rich-Quench-Lean (RQL) combustor. The specific intent was to identify approaches that would satisfy High Speed Civil Transport (HSCT) cycle operational requirements with regard to fuel-air ratio turndown capability, ignition, and stability margin without compromising the stringent emissions, performance, and reliability goals that this combustor would have to achieve. Four potential configurations were identified and three of these were refined and tested in a high-pressure modular RQL combustor rig. The tools used in the evolution of these concepts included models built with rapid fabrication techniques that were tested for airflow characteristics to confirm sizing and airflow management capability, spray patternation, and atomization characterization tests of these models and studies that were supported by Computational Fluid Dynamics analyses. Combustion tests were performed with each of the concepts at supersonic cruise conditions and at other critical conditions in the flight envelope, including the transition points of the variable geometry system, to identify performance, emissions, and operability impacts. Based upon the cold flow characterization, emissions results, acoustic behavior observed during the tests and consideration of mechanical, reliability, and implementation issues, the tri-swirler configuration was selected as the best variable geometry concept for incorporation in the RQL combustor evolution efforts for the HSCT.

Low NOx, Lean Direct Wall Injection Combustor Concept Developed

NASA Technical Reports Server (NTRS)

Tacina, Robert R.; Wey, Changlie; Choi, Kyung J.

2003-01-01

The low-emissions combustor development at the NASA Glenn Research Center is directed toward advanced high-pressure aircraft gas turbine applications. The emphasis of this research is to reduce nitrogen oxides (NOx) at high-power conditions and to maintain carbon monoxide and unburned hydrocarbons at their current low levels at low-power conditions. Low-NOx combustors can be classified into rich burn and lean burn concepts. Lean burn combustors can be further classified into lean-premixed-prevaporized (LPP) and lean direct injection (LDI) combustors. In both concepts, all the combustor air, except for liner cooling flow, enters through the combustor dome so that the combustion occurs at the lowest possible flame temperature. The LPP concept has been shown to have the lowest NOx emissions, but for advanced high-pressure-ratio engines, the possibly of autoignition or flashback precludes its use. LDI differs from LPP in that the fuel is injected directly into the flame zone and, thus, does not have the potential for autoignition or flashback and should have greater stability. However, since it is not premixed and prevaporized, the key is good atomization and mixing of the fuel quickly and uniformly so that flame temperatures are low and NOx formation levels are comparable to those of LPP.

A Noninvasive Method to Study Regulation of Extracellular Fluid Volume in Rats Using Nuclear Magnetic Resonance

EPA Science Inventory

Time-domain nuclear magnetic resonance (TD-NMR)-based measurement of body composition of rodents is an effective method to quickly and repeatedly measure proportions of fat, lean, and fluid without anesthesia. TD-NMR provides a measure of free water in a living animal, termed % f...

Scandal Clouds News Corporation's Move into Education

ERIC Educational Resources Information Center

Quillen, Ian

2011-01-01

When News Corporation announced last fall its entry into the education technology market, some observers said the media conglomerate led by Rupert Murdoch was a bad fit for education. Between the ownership of conservative-leaning outlets like Fox News and a reputation for identifying opportunities to generate lots of revenue very quickly, News…

A Buoyancy-based Method of Determining Fat Levels in Drosophila.

PubMed

Hazegh, Kelsey E; Reis, Tânia

2016-11-01

Drosophila melanogaster is a key experimental system in the study of fat regulation. Numerous techniques currently exist to measure levels of stored fat in Drosophila, but most are expensive and/or laborious and have clear limitations. Here, we present a method to quickly and cheaply determine organismal fat levels in L3 Drosophila larvae. The technique relies on the differences in density between fat and lean tissues and allows for rapid detection of fat and lean phenotypes. We have verified the accuracy of this method by comparison to body fat percentage as determined by neutral lipid extraction and gas chromatography coupled with mass spectrometry (GCMS). We furthermore outline detailed protocols for the collection and synchronization of larvae as well as relevant experimental recipes. The technique presented below overcomes the major shortcomings in the most widely used lipid quantitation methods and provides a powerful way to quickly and sensitively screen L3 larvae for fat regulation phenotypes while maintaining the integrity of the larvae. This assay has wide applications for the study of metabolism and fat regulation using Drosophila.

Gas turbine topping combustor

DOEpatents

Beer, Janos; Dowdy, Thomas E.; Bachovchin, Dennis M.

1997-01-01

A combustor for burning a mixture of fuel and air in a rich combustion zone, in which the fuel bound nitrogen in converted to molecular nitrogen. The fuel rich combustion is followed by lean combustion. The products of combustion from the lean combustion are rapidly quenched so as to convert the fuel bound nitrogen to molecular nitrogen without forming NOx. The combustor has an air radial swirler that directs the air radially inward while swirling it in the circumferential direction and a radial fuel swirler that directs the fuel radially outward while swirling it in the same circumferential direction, thereby promoting vigorous mixing of the fuel and air. The air inlet has a variable flow area that is responsive to variations in the heating value of the fuel, which may be a coal-derived fuel gas. A diverging passage in the combustor in front of a bluff body causes the fuel/air mixture to recirculate with the rich combustion zone.

Cycle time reduction using lean six sigma in make-to-order (MTO) environment: Conceptual framework

NASA Astrophysics Data System (ADS)

Man, Siti Mariam; Zain, Zakiyah; Nawawi, Mohd Kamal Mohd

2015-12-01

This paper outlines the framework for application of lean six sigma (LSS) methodology to improve semiconductor assembly cycle time in a make-to-order (MTO) business environment. The cycle time reduction is the prime objective in the context of an overall productivity improvement particularly in the MTO environment. The interaction of the production rate and cycle time is described, while the emphasis is on Define-Measure-Analyze-Improve-Control (DMAIC) and Plan-Do-Check-Act (PDCA) activities. A framework for the conceptual understanding is provided along with practical implementation issues. A relevant measure for the degree of flexibility (DOF) in the context of quick setup is also discussed.

Revisiting the Ladder on a Wall Problem

ERIC Educational Resources Information Center

Salu, Yehuda

2011-01-01

The problem of a ladder leaning on a wall has been a staple of introductory physics for years. It is discussed in numerous physics textbooks and in journals. Now, it even has an Internet presence. Postings from students seek help for "ladder on a wall" problems. A quick review of those postings would show that they all deal with frictionless…

Parametric Study of HTS Coil Quench Protection Strategies

NASA Astrophysics Data System (ADS)

Seibert, Joseph; Zarnstorff, Michael; Zhai, Yuhu

2016-10-01

Next generation fusion devices require high magnetic fields to adequately contain burning plasmas. Use of high temperature superconducting (HTS) coils to generate these magnetic fields would lower energy cost of operation as well as increase stability of the superconducting state compared to low temperature superconducting coils. However, use of HTS coils requires developing quench protection strategies to prevent damage to the coils. One technique involves the utilization of copper discs and other conductors mutually coupled to the HTS coil to quickly extract the current from the coil. Another technique allows conduction between HTS turns to reduce the current in the coil during quench. This project describes a parametric study of the HTS coil and resistive-conductor setup in order to determine limiting cases of the geometry in an attempt to optimize current extraction and coil protection during quench scenarios. This work was supported in part by the U.S. Department of Energy, Office of Science, Office of Workforce Development for Teachers and Scientists (WDTS) under the Science Undergraduate Laboratory Internship (SULI) program.

The Effect of Air Preheat at Atmospheric Pressure on the Formation of NO(x) in the Quick-Mix Sections of an Axially Staged Combustor

NASA Technical Reports Server (NTRS)

Vardakas, M. A.; Leong, M. Y.; Brouwer, J.; Samuelsen, G. S.; Holdeman, J. D.

1999-01-01

The Rich-burn/Quick-mix/Lean-burn (RQL) combustor concept has been proposed to minimize the formation of nitrogen oxides (NO(x)) in gas turbine systems. The success of this combustor strategy is dependent upon the efficiency of the mixing section bridging the fuel-rich and fuel-lean stages. Note that although these results were obtained from an experiment designed to study an RQL mixer, the link between mixing and NOx signatures is considerably broader than this application, in that the need to understand this link exists in most advanced combustors. The experiment reported herein was designed to study the effects of inlet air temperature on NO(x) formation in a mixing section. The results indicate that NO(x) emission is increased for all preheated cases compared to non-preheated cases. When comparing the various mixing modules, the affect of jet penetration is important, as this determines where NO(x) concentrations peak, and affects overall NO(x) production. Although jet air comprises 70 percent of the total airflow, the impact that jet air preheat has on overall NO(x) emissions is small compared to preheating both main and jet air flow.

Azide–Alkyne Click Conjugation on Quantum Dots by Selective Copper Coordination

PubMed Central

Mann, Victor R.; Powers, Alexander S.; Tilley, Drew C.; Sack, Jon T.; Cohen, Bruce E.

2018-01-01

Functionalization of nanocrystals is essential for their practical application, but synthesis on nanocrystal surfaces is limited by incompatibilities with certain key reagents. The copper-catalyzed azide-alkyne cycloaddition (CuAAC) is among the most useful methods for ligating molecules to surfaces, but has been largely useless for semiconductor quantum dots (QDs) because Cu+ ions quickly and irreversibly quench QD fluorescence. To discover non-quenching synthetic conditions for Cu-catalyzed click reactions on QD surfaces, we developed a combinatorial fluorescence assay to screen >2000 reaction conditions to maximize cycloaddition efficiency while minimizing QD quenching. We identify conditions for complete coupling without significant quenching, which are compatible with common QD polymer surfaces and various azide/alkyne pairs. Based on insight from the combinatorial screen and mechanistic studies of Cu coordination and quenching, we find that superstoichiometric concentrations of Cu can promote full coupling if accompanied by ligands that selectively compete the Cu from the QD surface but allow it to remain catalytically active. Applied to the conjugation of a K+ channel-specific peptidyl toxin to CdSe/ZnS QDs, we synthesize unquenched QD conjugates and image their specific and voltage-dependent affinity for K+ channels in live cells. PMID:29608274

Mixing and NOx Emission Calculations of Confined Reacting Jet Flows in Cylindrical and Annular Ducts

NASA Technical Reports Server (NTRS)

Oechsle, Victor L.; Connor, Christopher H.; Holdeman, James D. (Technical Monitor)

2000-01-01

Rapid mixing of cold lateral jets with hot cross-stream flows in confined configurations is of practical interest in gas turbine combustors as it strongly affects combustor exit temperature quality, and gaseous emissions in for example rich-lean combustion. It is therefore important to further improve our fundamental understanding of the important processes of dilution jet mixing especially when the injected jet mass flow rate exceeds that of the cross-stream. The results reported in this report describe some of the main flow characteristics which develop in the mixing process in a cylindrical duct. A three-dimensional computational fluid dynamics (CFD) code has been used to predict the mixing flow field characteristics and NOx emission in a quench section of a rich-burn/quick-mix/lean-burn (RQL) combustor. Sixty configurations have been analyzed in both circular and annular geometries in a fully reacting environment simulating the operating condition of an actual RQL gas turbine combustion liner. The evaluation matrix was constructed by varying the number of orifices per row and orifice shape. Other parameters such as J (momentum-flux ratio), MR (mass flowrate ratio), DR (density ratio), and mixer sector orifice ACd (effective orifice area) were maintained constant throughout the entire study. The results indicate that the mixing flow field can be correlated with the NOx production if they are referenced with the stoichiometric equivalence ratio value and not the equilibrium value. The mixing flowfields in both circular and annular mixers are different. The penetration of equal jets in both annular and circular geometries is vastly different which significantly affects the performance of the mixing section. In the computational results with the circular mixer, most of the NOx formation occurred behind the orifice starting at the orifice wake region. General trends have been observed in the NOx production as the number of orifices is changed and this appears to be common for all hole configurations and mixer types (circular or annular). The performance of any orifice shape (in producing minimum NOx) appears to be acceptable if the number of orifices can be freely varied in order to attain the optimum jet penetration.

Advanced Low-Emissions Catalytic-Combustor Program, phase 1. [aircraft gas turbine engines

NASA Technical Reports Server (NTRS)

Sturgess, G. J.

1981-01-01

Six catalytic combustor concepts were defined, analyzed, and evaluated. Major design considerations included low emissions, performance, safety, durability, installations, operations and development. On the basis of these considerations the two most promising concepts were selected. Refined analysis and preliminary design work was conducted on these two concepts. The selected concepts were required to fit within the combustor chamber dimensions of the reference engine. This is achieved by using a dump diffuser discharging into a plenum chamber between the compressor discharge and the turbine inlet, with the combustors overlaying the prediffuser and the rear of the compressor. To enhance maintainability, the outer combustor case for each concept is designed to translate forward for accessibility to the catalytic reactor, liners and high pressure turbine area. The catalytic reactor is self-contained with air-cooled canning on a resilient mounting. Both selected concepts employed integrated engine-starting approaches to raise the catalytic reactor up to operating conditions. Advanced liner schemes are used to minimize required cooling air. The two selected concepts respectively employ fuel-rich initial thermal reaction followed by rapid quench and subsequent fuel-lean catalytic reaction of carbon monoxide, and, fuel-lean thermal reaction of some fuel in a continuously operating pilot combustor with fuel-lean catalytic reaction of remaining fuel in a radially-staged main combustor.

Gas turbine topping combustor

DOEpatents

Beer, J.; Dowdy, T.E.; Bachovchin, D.M.

1997-06-10

A combustor is described for burning a mixture of fuel and air in a rich combustion zone, in which the fuel bound nitrogen in converted to molecular nitrogen. The fuel rich combustion is followed by lean combustion. The products of combustion from the lean combustion are rapidly quenched so as to convert the fuel bound nitrogen to molecular nitrogen without forming NOx. The combustor has an air radial swirler that directs the air radially inward while swirling it in the circumferential direction and a radial fuel swirler that directs the fuel radially outward while swirling it in the same circumferential direction, thereby promoting vigorous mixing of the fuel and air. The air inlet has a variable flow area that is responsive to variations in the heating value of the fuel, which may be a coal-derived fuel gas. A diverging passage in the combustor in front of a bluff body causes the fuel/air mixture to recirculate with the rich combustion zone. 14 figs.

Strategies for laser-induced fluorescence detection of nitric oxide in high-pressure flames. I. A-X (0,0) excitation

NASA Astrophysics Data System (ADS)

Bessler, Wolfgang G.; Schulz, Christof; Lee, Tonghun; Jeffries, Jay B.; Hanson, Ronald K.

2002-06-01

Three different high-pressure flame measurement strategies for NO laser-induced fluorescence (LIF) with A-X (0,0) excitation have been studied previously with computational simulations and experiments in flames up to 15 bars. Interference from O2 LIF is a significant problem in lean flames for NO LIF measurements, and pressure broadening and quenching lead to increased interference with increased pressure. We investigate the NO LIF signal strength, interference by hot molecular oxygen, and temperature dependence of the three previous schemes and for two newly chosen excitation schemes with wavelength-resolved LIF measurements in premixed methane and air flames at pressures between 1 and 60 bars and a range of fuel /air ratios. In slightly lean flames with an equivalence ratio of 0.83 at 60 bars, the contribution of O2 LIF to the NO LIF signal varies between 8% and 29% for the previous schemes. The O2 interference is best suppressed with excitation at 226.03 nm.

Quench of non-Markovian coherence in the deep sub-Ohmic spin–boson model: A unitary equilibration scheme

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yao, Yao, E-mail: yaoyao@fudan.edu.cn

The deep sub-Ohmic spin–boson model shows a longstanding non-Markovian coherence at low temperature. Motivating to quench this robust coherence, the thermal effect is unitarily incorporated into the time evolution of the model, which is calculated by the adaptive time-dependent density matrix renormalization group algorithm combined with the orthogonal polynomials theory. Via introducing a unitary heating operator to the bosonic bath, the bath is heated up so that a majority portion of the bosonic excited states is occupied. It is found in this situation the coherence of the spin is quickly quenched even in the coherent regime, in which the non-Markovianmore » feature dominates. With this finding we come up with a novel way to implement the unitary equilibration, the essential term of the eigenstate-thermalization hypothesis, through a short-time evolution of the model.« less

A "turn-on" fluorescent copper biosensor based on DNA cleavage-dependent graphene-quenched DNAzyme.

PubMed

Liu, Meng; Zhao, Huimin; Chen, Shuo; Yu, Hongtao; Zhang, Yaobin; Quan, Xie

2011-06-15

A novel and promising "turn-on" fluorescent Cu(2+) biosensor is designed based on graphene-DNAzyme catalytic beacon. Due to the essential surface and quenching properties of two-dimensional graphene, it can function as both "scaffold" and "quencher" of the Cu(2+)-dependent DNAzyme, facilitating the formation of self-assembled graphene-quenched DNAzyme complex. However, Cu(2+)-induced catalytic reaction disturbs the graphene-DNAzyme conformation, which will produce internal DNA cleavage-dependent effect. In this case, the quenched fluorescence in graphene-DNAzyme is quickly recovered to a large extent in 15 min. Compared with common DNAzyme-based sensors, the presented graphene-based catalytic beacon greatly improves the signal-to-background ratio, hence increasing the sensitivity (LOD=0.365 nM). Furthermore, the controllable DNA cleavage reaction provides an original and alternative internal method to regulate the interaction between graphene and DNA relative to the previous external sequence-specific hybridization-dependent regulation, which will open new opportunities for nucleic studies and sensing applications in the future. Copyright © 2011 Elsevier B.V. All rights reserved.

Quench protection challenges in long nb3sn accelerator magnets

NASA Astrophysics Data System (ADS)

Salmi, Tiina-Mari; Ambrosio, G.; Caspi, S.; Chlachidze, Guram; Dhallé, Marc; Felice, Helene; Ferracin, Paolo; Marchevsky, M.; Sabbi, G. L.; ten Kate, H. H. J.

2012-06-01

The quench protection of the several meter long, large aperture high-field Nb3Sn quadrupoles that the LARP collaboration is developing for the LHC interaction region upgrade, requires efficient protection heaters to quickly generate large resistive segments across the windings. To support the protection design, experiments in the recently tested LARP R&D magnets are aimed to characterize the coil response to different protection schemes. In particular, the delay to quench and the final hotspot temperatures are evaluated after firing the heaters at different powering regimes and coverage. Also, the contribution of external energy extraction is investigated. Based on the performed studies and computer simulations, it seems that if the same protection efficiency per unit length that is measured in a 1 m long model magnet can be scaled to a 3.6 m long magnet, and the heater coverage can be improved, about 1 MJ/m of stored energy can be absorbed in the magnet after a quench. However, significant technology developments are needed to scale the protection heater efficiency to longer magnets and to increase the coverage.

Design and preliminary results of a fuel flexible industrial gas turbine combustor

NASA Technical Reports Server (NTRS)

Novick, A. S.; Troth, D. L.; Yacobucci, H. G.

1981-01-01

The design characteristics are presented of a fuel tolerant variable geometry staged air combustor using regenerative/convective cooling. The rich/quench/lean variable geometry combustor is designed to achieve low NO(x) emission from fuels containing fuel bound nitrogen. The physical size of the combustor was calculated for a can-annular combustion system with associated operating conditions for the Allison 570-K engine. Preliminary test results indicate that the concept has the potential to meet emission requirements at maximum continuous power operation. However, airflow sealing and improved fuel/air mixing are necessary to meet Department of Energy program goals.

Slag processing system for direct coal-fired gas turbines

DOEpatents

Pillsbury, Paul W.

1990-01-01

Direct coal-fired gas turbine systems and methods for their operation are provided by this invention. The systems include a primary combustion compartment coupled to an impact separator for removing molten slag from hot combustion gases. Quenching means are provided for solidifying the molten slag removed by the impact separator, and processing means are provided forming a slurry from the solidified slag for facilitating removal of the solidified slag from the system. The released hot combustion gases, substantially free of molten slag, are then ducted to a lean combustion compartment and then to an expander section of a gas turbine.

The Evolution of the Center on Education Policy: From an Idea to a Major Influence

ERIC Educational Resources Information Center

Lewis, Anne

2012-01-01

During hearings in the late 1980s on education legislation, the frustrated chairman of the Education and Labor Committee of the U.S. House of Representatives, Rep. Gus Hawkins (D-CA), would sometimes lean over to his chief counsel and ask: "Why can't these people agree on the facts? If they did that, we could solve these problems quickly." That…

Dependency properties of the amorphous alloy Co58Ni10Fe5Si11B16 on technological parameters of spinning

NASA Astrophysics Data System (ADS)

Frolov, A. M.; Tkachev, V. V.; Fedorets, A. N.; Pustovalov, E. V.; Kraynova, G. S.; Dolzhikov, S. V.; Ilin, N. V.; Tsesarskaya, A. K.

2017-09-01

The tapes are quickly quenched onto a rotating drum. The structure of mechanical and physical properties is studied depending on the spinning parameters. An approach is proposed for the classification of obtained bands based on the statistics of the microrelief of their surfaces.

CFD analysis of jet mixing in low NOx flametube combustors

NASA Technical Reports Server (NTRS)

Talpallikar, M. V.; Smith, C. E.; Lai, M. C.; Holdeman, J. D.

1991-01-01

The Rich-burn/Quick-mix/Lean-burn (RQL) combustor was identified as a potential gas turbine combustor concept to reduce NO(x) emissions in High Speed Civil Transport (HSCT) aircraft. To demonstrate reduced NO(x) levels, cylindrical flametube versions of RQL combustors are being tested at NASA Lewis Research Center. A critical technology needed for the RQL combustor is a method of quickly mixing by-pass combustion air with rich-burn gases. Jet mixing in a cylindrical quick-mix section was numerically analyzed. The quick-mix configuration was five inches in diameter and employed twelve radial-inflow slots. The numerical analyses were performed with an advanced, validated 3-D Computational Fluid Dynamics (CFD) code named REFLEQS. Parametric variation of jet-to-mainstream momentum flux ratio (J) and slot aspect ratio was investigated. Both non-reacting and reacting analyses were performed. Results showed mixing and NO(x) emissions to be highly sensitive to J and slot aspect ratio. Lowest NO(x) emissions occurred when the dilution jet penetrated to approximately mid-radius. The viability of using 3-D CFD analyses for optimizing jet mixing was demonstrated.

CFD analysis of jet mixing in low NO(x) flametube combustors

NASA Technical Reports Server (NTRS)

Talpallikar, M. V.; Smith, C. E.; Lai, M. C.; Holdeman, J. D.

1991-01-01

The Rich-burn/Quick-mix/Lean-burn (RQL) combustor has been identified as a potential gas turbine combustor concept to reduce NO(x) emissions in High Speed Civil Transport (HSCT) aircraft. To demonstrate reduced NO(x) levels, cylindrical flametube versions of RQL combustors are being tested at NASA Lewis Research Center. A critical technology needed for the RQL combustor is a method of quickly mixing by-pass combustion air with rich-burn gases. Jet mixing in a cylindrical quick-mix section was numerically analyzed. The quick-mix configuration was five inches in diameter and employed twelve radial-inflow slots. The numerical analyses were performed with an advanced, validated 3D Computational Fluid Dynamics (CFD) code named REFLEQS. Parametric variation of jet-to-mainstream momentum flux ratio (J) and slot aspect ratio was investigated. Both non-reacting and reacting analyses were performed. Results showed mixing and NO(x) emissions to be highly sensitive to J and slot aspect ratio. Lowest NO(x) emissions occurred when the dilution jet penetrated to approximately mid-radius. The viability of using 3D CFD analyses for optimizing jet mixing was demonstrated.

Applying science and strategy to operating room workforce management.

PubMed

Butler, Victoria; Clinton, Christopher; Sagi, Harsha K; Kenney, Robert; Barsoum, Wael K

2012-01-01

The traditional means of planning nurse staffing for operating rooms are either poorly translated to the setting or do not provide decision makers with a platform to defend their needs, especially in an era of health care reform. The surgical operations department of the Cleveland Clinic initiated a quality improvement project aimed at applying a scientific method to operating room staffing. One goal was to provide a defensible plan for allocating direct caregiver positions. A second goal was to provide a quick and easy way for nurse managers and directors to track positions and graphically depict the effect of vacancies and orientation on their staffing budgets. Using an objective, scientific method allows position requests to be approved quickly and allows managers to feel much more comfortable functioning in a "lean" mode because they know needed positions will be approved quickly. Managers and directors also have found that graphically depicting numbers of vacant positions, as well as staff in orientation, could quickly relate a story visually rather than getting "bogged down" in narrative (often losing finance administrators along the way).

Redesigning care at the Flinders Medical Centre: clinical process redesign using "lean thinking".

PubMed

Ben-Tovim, David I; Bassham, Jane E; Bennett, Denise M; Dougherty, Melissa L; Martin, Margaret A; O'Neill, Susan J; Sincock, Jackie L; Szwarcbord, Michael G

2008-03-17

*The Flinders Medical Centre (FMC) Redesigning Care program began in November 2003; it is a hospital-wide process improvement program applying an approach called "lean thinking" (developed in the manufacturing sector) to health care. *To date, the FMC has involved hundreds of staff from all areas of the hospital in a wide variety of process redesign activities. *The initial focus of the program was on improving the flow of patients through the emergency department, but the program quickly spread to involve the redesign of managing medical and surgical patients throughout the hospital, and to improving major support services. *The program has fallen into three main phases, each of which is described in this article: "getting the knowledge"; "stabilising high-volume flows"; and "standardising and sustaining". *Results to date show that the Redesigning Care program has enabled the hospital to provide safer and more accessible care during a period of growth in demand.

Measurement and Computation of Supersonic Flow in a Lobed Diffuser-Mixer for Trapped Vortex Combustors

NASA Technical Reports Server (NTRS)

Brankovic, Andreja; Ryder, Robert C., Jr.; Hendricks, Robert C.; Liu, Nan-Suey; Gallagher, John R.; Shouse, Dale T.; Roquemore, W. Melvyn; Cooper, Clayton S.; Burrus, David L.; Hendricks, John A.

2002-01-01

The trapped vortex combustor (TVC) pioneered by Air Force Research Laboratories (AFRL) is under consideration as an alternative to conventional gas turbine combustors. The TVC has demonstrated excellent operational characteristics such as high combustion efficiency, low NO(x) emissions, effective flame stabilization, excellent high-altitude relight capability, and operation in the lean-burn or rich burn-quick quench-lean burn (RQL) modes of combustion. It also has excellent potential for lowering the engine combustor weight. This performance at low to moderate combustor mach numbers has stimulated interest in its ability to operate at higher combustion mach number, and for aerospace, this implies potentially higher flight mach numbers. To this end, a lobed diffuser-mixer that enhances the fuel-air mixing in the TVC combustor core was designed and evaluated, with special attention paid to the potential shock system entering the combustor core. For the present investigation, the lobed diffuser-mixer combustor rig is in a full annular configuration featuring sixfold symmetry among the lobes, symmetry within each lobe, and plain parallel, symmetric incident flow. During hardware cold-flow testing, significant discrepancies were found between computed and measured values for the pitot-probe-averaged static pressure profiles at the lobe exit plane. Computational fluid dynamics (CFD) simulations were initiated to determine whether the static pressure probe was causing high local flow-field disturbances in the supersonic flow exiting the diffuser-mixer and whether shock wave impingement on the pitot probe tip, pressure ports, or surface was the cause of the discrepancies. Simulations were performed with and without the pitot probe present in the modeling. A comparison of static pressure profiles without the probe showed that static pressure was off by nearly a factor of 2 over much of the radial profile, even when taking into account potential axial displacement of the probe by up to 0.25 in. (0.64 cm). Including the pitot probe in the CFD modeling and data interpretation lead to good agreement between measurement and prediction. Graphical inspection of the results showed that the shock waves impinging on the probe surface were highly nonuniform, with static pressure varying circumferentially among the pressure ports by over 10 percent in some cases. As part of the measurement methodology, such measurements should be routinely supplemented with CFD analyses that include the pitot probe as part of the flow-path geometry.

Glucose biosensor based on nanocomposite films of CdTe quantum dots and glucose oxidase.

PubMed

Li, Xinyu; Zhou, Yunlong; Zheng, Zhaozhu; Yue, Xiuli; Dai, Zhifei; Liu, Shaoqin; Tang, Zhiyong

2009-06-02

A blood glucose sensor has been developed based on the multilayer films of CdTe semiconductor quantum dots (QDs) and glucose oxidase (GOD) by using the layer-by-layer assembly technique. When the composite films were contacted with glucose solution, the photoluminescence of QDs in the films was quickly quenched because the enzyme-catalyzed reaction product (H2O2) of GOD and glucose gave rise to the formation of surface defects on QDs. The quenching rate was a function of the concentration of glucose. The linear range and sensitivity for glucose determination could be adjusted by controlling the layers of QDs and GOD. The biosensor was used to successfully determine the concentration of blood glucose in real serum samples without sample pretreatment and exhibited satisfactory reproducibility and accuracy.

Information as Power: An Anthology of Selected United States Army War College Student Papers. Volume 1

DTIC Science & Technology

2006-01-01

audience. Things like web logs are providing a different way to access news and commentary. Bloggers invite the contributions of their readers...enough, there were wide differences in media coverage – some left leaning press and bloggers were quick to criticize this as a “war crime within a war...in the JOC. It is now after dinner and we are less than 12 hours from election time on January 29, 2005. The beautiful part is that this

Nanostructured biosensor using bioluminescence quenching technique for glucose detection.

PubMed

Chen, Longyan; Chen, Longyi; Dotzert, Michelle; Melling, C W James; Zhang, Jin

2017-08-22

Most methods for monitoring glucose level require an external energy source which may limit their application, particularly in vivo test. Bioluminescence technique offers an alternative way to provide emission light without external energy source by using bioluminescent proteins found from firefly or marine vertebrates and invertebrates. For quick and non-invasive detection of glucose, we herein developed a nanostructured biosensor by applying the bioluminescence technique. Luciferase bioluminescence protein (Rluc) is conjugated with β-cyclodextrin (β-CD). The bioluminescence intensity of Rluc can be quenched by 8 ± 3 nm gold nanoparticles (Au NPs) when Au NPs covalently bind to β-CD. In the presence of glucose, Au NPs are replaced and leave far from Rluc through a competitive reaction, which results in the restored bioluminescence intensity of Rluc. A linear relationship is observed between the restored bioluminescence intensity and the logarithmic glucose concentration in the range of 1-100 µM. In addition, the selectivity of this designed sensor has been evaluated. The performance of the senor for determination of the concentration of glucose in the blood of diabetic rats is studied for comparison with that of the concentration of glucose in aqueous. This study demonstrates the design of a bioluminescence sensor for quickly detecting the concentration of glucose sensitively.

Is the Electron Avalanche Process in a Martian Dust Devil Self-Quenching?

NASA Technical Reports Server (NTRS)

Farrell, William M.; McLain, Jason L.; Collier, M. R.; Keller, J. W.; Jackson, T. J.; Delory, G. T.

2015-01-01

Viking era laboratory experiments show that mixing tribocharged grains in a low pressure CO2 gas can form a discharge that glows, indicating the presence of an excited electron population that persists over many seconds. Based on these early experiments, it has been predicted that martian dust devils and storms may also contain a plasma and new plasma chemical species as a result of dust grain tribo-charging. However, recent results from modeling suggest a contrasting result: that a sustained electron discharge may not be easily established since the increase in gas conductivity would act to short-out the local E-fields and quickly dissipate the charged grains driving the process. In essence, the system was thought to be self-quenching (i.e., turn itself off). In this work, we attempt to reconcile the difference between observation and model via new laboratory measurements. We conclude that in a Mars-like low pressure CO2 atmosphere and expected E-fields, the electron current remains (for the most part) below the expected driving tribo-electric dust currents (approx. 10 microA/m(exp. 2)), thereby making quenching unlikely.

Influence of Geometry and Flow Variations on NO Formation in the Quick Mixer of a Staged Combustor

NASA Technical Reports Server (NTRS)

Hatch, M. S.; Sowa, W. A.; Samuelsen, G. S.; Holdeman, J. D.

1995-01-01

Staged combustion, such as Rich-Burn/Quick-Mix/Lean-Burn (RQL), is a viable strategy to meet nitric oxide (NO) emission goals for both stationary and propulsion gas turbine engines. A critical element of the design is the quick mixer section where the potential for NO production is high. While numerical calculations of the quick mixer under reacting conditions have been conducted, the hostile environment and lack of appropriate diagnostics have, to date, precluded experimental probing of the reacting case. As an alternative to understanding the effect of geometry and flow variations on the production of NO in the quick mixer, the present paper presents (1) a series of non-reacting parametric studies, and (2) a computational method to extrapolate the results of the non-reacting experiments to reacting conditions. The results show that the rate of NO production is highest in the immediate vicinity of the injection plane. For a given momentum flux ratio between the jets and mainstream, the most effective mixing geometry is that which mixes effectively in both (1) the plane of injection, and (2) the wall regions downstream of the plan of injection. The tailoring of the mixing is key to minimize the NO formed. As a result, the best overall mixer with respect to the minimization of NO production may depend on the system specific characteristics of the particular application.

Quick and simple estimation of bacteria using a fluorescent paracetamol dimer-Au nanoparticle composite

NASA Astrophysics Data System (ADS)

Sahoo, Amaresh Kumar; Sharma, Shilpa; Chattopadhyay, Arun; Ghosh, Siddhartha Sankar

2012-02-01

Rapid, simple and sensitive detection of bacterial contamination is critical for safeguarding public health and the environment. Herein, we report an easy method of detection as well as enumeration of the bacterial cell number on the basis of fluorescence quenching of a non-antibacterial fluorescent nanocomposite, consisting of paracetamol dimer (PD) and Au nanoparticles (NPs), in the presence of bacteria. The composite was synthesized by reaction of paracetamol (p-hydroxyacetanilide) with HAuCl4. The Au NPs of the composite were characterized using UV-Vis spectroscopy, transmission electron microscopy (TEM), X-ray diffraction and selected area electron diffraction analysis. The paracetamol dimer in the composite showed emission peak at 435 nm when excited at 320 nm. The method successfully detected six bacterial strains with a sensitivity of 100 CFU mL-1. The Gram-positive and Gram-negative bacteria quenched the fluorescence of the composite differently, making it possible to distinguish between the two. The TEM analysis showed interaction of the composite with bacteria without any apparent damage to the bacteria. The chi-square test established the accuracy of the method. Quick, non-specific and highly sensitive detection of bacteria over a broad range of logarithmic dilutions within a short span of time demonstrates the potential of this method as an alternative to conventional methods.Rapid, simple and sensitive detection of bacterial contamination is critical for safeguarding public health and the environment. Herein, we report an easy method of detection as well as enumeration of the bacterial cell number on the basis of fluorescence quenching of a non-antibacterial fluorescent nanocomposite, consisting of paracetamol dimer (PD) and Au nanoparticles (NPs), in the presence of bacteria. The composite was synthesized by reaction of paracetamol (p-hydroxyacetanilide) with HAuCl4. The Au NPs of the composite were characterized using UV-Vis spectroscopy, transmission electron microscopy (TEM), X-ray diffraction and selected area electron diffraction analysis. The paracetamol dimer in the composite showed emission peak at 435 nm when excited at 320 nm. The method successfully detected six bacterial strains with a sensitivity of 100 CFU mL-1. The Gram-positive and Gram-negative bacteria quenched the fluorescence of the composite differently, making it possible to distinguish between the two. The TEM analysis showed interaction of the composite with bacteria without any apparent damage to the bacteria. The chi-square test established the accuracy of the method. Quick, non-specific and highly sensitive detection of bacteria over a broad range of logarithmic dilutions within a short span of time demonstrates the potential of this method as an alternative to conventional methods. Electronic supplementary information (ESI) available. See DOI: 10.1039/c2nr11837h

Biogas Laminar Burning Velocity and Flammability Characteristics in Spark Ignited Premix Combustion

NASA Astrophysics Data System (ADS)

Anggono, Willyanto; Wardana, I. N. G.; Lawes, M.; Hughes, K. J.; Wahyudi, Slamet; Hamidi, Nurkholis; Hayakawa, Akihiro

2013-04-01

Spherically expanding flames propagating at constant pressure were employed to determine the laminar burning velocity and flammability characteristics of biogas-air mixtures in premixed combustion to uncover the fundamental flame propagation characteristics of a new alternative and renewable fuel. The results are compared with those from a methane-air flame. Biogas is a sustainable and renewable fuel that is produced in digestion facilities. The composition of biogas discussed in this paper consists of 66.4% methane, 30.6% carbon dioxide and 3% nitrogen. Burning velocity was measured at various equivalence ratios (phi) using a photographic technique in a high pressure fan-stirred bomb, the initial condition being at room temperature and atmospheric pressure. The flame for methane-air mixtures propagates from phi=0.6 till phi=1.3. The flame at phi >= 1.4 does not propagate because the combustion reaction is quenched by the larger mass of fuel. At phi<=0.5, it does not propagate as well since the heat of reaction is insufficient to burn the mixtures. The flame for biogas-air mixtures propagates in a narrower range, that is from phi=0.6 to phi=1.2. Different from the methane flame, the biogas flame does not propagate at phi>=1.3 because the heat absorbed by inhibitors strengthens the quenching effect by the larger mass of fuel. As in the methane flame, the biogas flame at phi<=0.5 does not propagate. This shows that the effect of inhibitors in extremely lean mixtures is small. Compared to a methane-air mixture, the flammability characteristic (flammable region) of biogas becomes narrower in the presence of inhibitors (carbon dioxide and nitrogen) and the presence of inhibitors causes a reduction in the laminar burning velocity. The inhibitor gases work more effectively at rich mixtures because the rich biogas-air mixtures have a higher fraction of carbon dioxide and nitrogen components compared to the lean biogas-air mixtures.

A Case Study: Using Delmia at Kennedy Space Center to Support NASA's Constellation Program

NASA Technical Reports Server (NTRS)

Kickbusch, Tracey; Humeniuk, Bob

2010-01-01

The presentation examines the use of Delmia (Digital Enterprise Lean Manufacturing Interactive Application) for digital simulation in NASA's Constellation Program. Topics include an overview of the Kennedy Space Center (KSC) Design Visualization Group tasks, NASA's Constellation Program, Ares 1 ground processing preliminary design review, and challenges and how Delmia is used at KSC, Challenges include dealing with large data sets, creating and maintaining KSC's infrastructure, gathering customer requirements and meeting objectives, creating life-like simulations, and providing quick turn-around on varied products,

Superswollen microemulsions stabilized by shear and trapped by a temperature quench.

PubMed

Roger, Kevin; Olsson, Ulf; Zackrisson-Oskolkova, Malin; Lindner, Peter; Cabane, Bernard

2011-09-06

We studied the solubilization of oil in the C(16)E(8)/hexadecane/H(2)O system. Close to the phase inversion temperature (PIT), the system, at equilibrium, can form either homogeneous states (i.e., microemulsions) at high surfactant concentrations or three-phase states at lower concentrations. We show that, under gentle shear, at a line we named the clearing boundary (CB), located a few degrees below the PIT, the system is homogeneous regardless of the surfactant concentration. We relate this shift of the microemulsion boundary to shear-induced disruption of the asymmetric bicontinuous structure. Although this state quickly relaxes to equilibrium when shear is stopped, we show that it is still possible to trap it into a metastable state through a temperature quench. This method is the sub-PIT emulsification that we described in a previous work (Roger Langmuir 2010, 26, 3860-3867). © 2011 American Chemical Society

Experimental and Computational Study of Trapped Vortex Combustor Sector Rig with Tri-pass Diffuser

NASA Technical Reports Server (NTRS)

Hendricks, Robert C.; Shouse, D. T.; Roquemore, W. M.; Burrus, D. L.; Duncan, B. S.; Ryder, R. C.; Brankovic, A.; Liu, N.-S.; Gallagher, J. R.; Hendricks, J. A.

2001-01-01

The Trapped Vortex Combustor (TVC) potentially offers numerous operational advantages over current production gas turbine engine combustors. These include lower weight, lower pollutant emissions, effective flame stabilization, high combustion efficiency, excellent high altitude relight capability, and operation in the lean burn or RQL (Rich burn/Quick mix/Lean burn) modes of combustion. The present work describes the operational principles of the TVC, and provides detailed performance data on a configuration featuring a tri-pass diffusion system. Performance data include EINOx (NO(sub x) emission index) results for various fuel-air ratios and combustor residence times, combustion efficiency as a function of combustor residence time, and combustor lean blow-out (LBO) performance. Computational fluid dynamics (CFD) simulations using liquid spray droplet evaporation and combustion modeling are performed and related to flow structures observed in photographs of the combustor. The CFD results are used to understand the aerodynamics and combustion features under different fueling conditions. Performance data acquired to date are favorable in comparison to conventional gas turbine combustors. Further testing over a wider range of fuel-air ratios, fuel flow splits, and pressure ratios is in progress to explore the TVC performance. In addition, alternate configurations for the upstream pressure feed, including bi-pass diffusion schemes, as well as variations on the fuel injection patterns, are currently in test and evaluation phases.

Validation of the Spanish version of the McLean Screening Instrument for Borderline Personality Disorder.

PubMed

Soler, Joaquim; Domínguez-Clavé, Elisabet; García-Rizo, Clemente; Vega, Daniel; Elices, Matilde; Martín-Blanco, Ana; Feliu-Soler, Albert; Carmona, Cristina; Pascual, Juan C

Borderline personality disorder (BPD) is a common and severe mental illness. Early detection is important and reliable screening instruments are required. To date, however, there has been no evidence of any specific BPD screening tool validated for the Spanish-speaking population. The McLean Screening Instrument for Borderline Personality Disorder (MSI-BPD) is a 10-item self-report questionnaire that can detect the presence of BPD in a reliable and quick manner. The aim of the present study is the validation of the MSI-BPD for its use in the Spanish-speaking population. Psychometric properties of the MSI-BPD Spanish version were examined in a sample of 344 participants (170 outpatients with the possible diagnosis of BPD and 174 healthy controls). Exploratory factor analysis revealed the existence of a bi-factorial structure. The scale showed a high internal consistency (KR-20=0.873) and an optimal test-retest reliability (ICC=0.87). Using logistic regression analyses and taking the DIB-R as reference, a best cut-off of 7 was determined, obtaining a good sensitivity (0.71) and specificity (0.68). The area under the curve, was 0.742 (95% CI 0.660-0.824). The discriminant analysis showed a classification ability of 72.8%. The Spanish version of the MSI-BPD has good psychometric properties as a measure for the screening of BPD. Its ease and quickness of use make it valuable to detect the presence of BPD in clinical and research settings. Copyright © 2016 SEP y SEPB. Publicado por Elsevier España, S.L.U. All rights reserved.

Quick Reaction Evaluation of Materials for Systems Applications.

DTIC Science & Technology

1980-04-01

The six slack-quenched aluminum alloy plates used in this program were: (1) 2024 -T851; 2.75 inches (60 mm) thick, (2) 2024 - T351 ; 2.00 inches (51 mm...compact (CT) specimen machined from aluminum alloys 7075-T6 and 2024 - T351 , titanium 6A1-4V, and 4340 steel. Deviation between the two curves is small...1.6 Complete Fatigue Crack Growth Rate Curves for Aluminum Alloy 2124-T851 Including Crack Growth Modeling 44 1.7 Crack Length Determination for the

Low Emissions RQL Flametube Combustor Component Test Results

NASA Technical Reports Server (NTRS)

Holdeman, James D.; Chang, Clarence T.

2001-01-01

This report describes and summarizes elements of the High Speed Research (HSR) Low Emissions Rich burn/Quick mix/Lean burn (RQL) flame tube combustor test program. This test program was performed at NASA Glenn Research Center circa 1992. The overall objective of this test program was to demonstrate and evaluate the capability of the RQL combustor concept for High Speed Civil Transport (HSCT) applications with the goal of achieving NOx emission index levels of 5 g/kg-fuel at representative HSCT supersonic cruise conditions. The specific objectives of the tests reported herein were to investigate component performance of the RQL combustor concept for use in the evolution of ultra-low NOx combustor design tools. Test results indicated that the RQL combustor emissions and performance at simulated supersonic cruise conditions were predominantly sensitive to the quick mixer subcomponent performance and not sensitive to fuel injector performance. Test results also indicated the mixing section configuration employing a single row of circular holes was the lowest NOx mixer tested probably due to the initial fast mixing characteristics of this mixing section. However, other quick mix orifice configurations such as the slanted slot mixer produced substantially lower levels of carbon monoxide emissions most likely due to the enhanced circumferential dispersion of the air addition. Test results also suggested that an optimum momentum-flux ratio exists for a given quick mix configuration. This would cause undesirable jet under- or over-penetration for test conditions with momentum-flux ratios below or above the optimum value. Tests conducted to assess the effect of quick mix flow area indicated that reduction in the quick mix flow area produced lower NOx emissions at reduced residence time, but this had no effect on NOx emissions measured at similar residence time for the configurations tested.

Agile rediscovering values: Similarities to continuous improvement strategies

NASA Astrophysics Data System (ADS)

Díaz de Mera, P.; Arenas, J. M.; González, C.

2012-04-01

Research in the late 80's on technological companies that develop products of high value innovation, with sufficient speed and flexibility to adapt quickly to changing market conditions, gave rise to the new set of methodologies known as Agile Management Approach. In the current changing economic scenario, we considered very interesting to study the similarities of these Agile Methodologies with other practices whose effectiveness has been amply demonstrated in both the West and Japan. Strategies such as Kaizen, Lean, World Class Manufacturing, Concurrent Engineering, etc, would be analyzed to check the values they have in common with the Agile Approach.

Multiparameter spatio-thermochemical probing of flame–wall interactions advanced with coherent Raman imaging

DOE PAGES

Bohlin, Gustav Alexis; Jainski, Christopher; Patterson, Brian D.; ...

2016-08-10

Ultrabroadband coherent anti-Stokes Ra man spectroscopy (CARS) has been developed for one -dimensional imaging of temperature and major species distributions simultaneously in the near-wall region of a methane/air flame supported on a side-wall-quenching (SWQ) burner. Automatic temporal and spatial overlap of the ~7 femtosecond pump and Stokes pulses is achieved utilizing a two-beam CARS phase-matching scheme, and the crossed ~75 picosecond probe beam provide s excellent spatial sectioning of the probed location. Concurrent detection of N 2, O 2, H 2, CO, CO 2, and CH 4 is demonstrated while high-fidelity flame thermometry is assessed from the N 2 puremore » rotational S-branch in a one-dimensional -CARS imaging configuration. A methane/air premixed flame at lean, stoichiometric, and rich conditions ( Φ = 0.83, 1.0 , and 1.2) and Reynolds number = 5,000 is probed as it quenches against a cooled steel side- wall parallel to the flow providing a persistent flame-wall interaction. Here, an imaging resolution of better than 40 μm is achieved across the field -of-view, thus allowing thermochemical states (temperature and major species) of the thermal boundary layer to be resolved to within ~30 μm of the interface.« less

Multiparameter spatio-thermochemical probing of flame–wall interactions advanced with coherent Raman imaging

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bohlin, Gustav Alexis; Jainski, Christopher; Patterson, Brian D.

Ultrabroadband coherent anti-Stokes Ra man spectroscopy (CARS) has been developed for one -dimensional imaging of temperature and major species distributions simultaneously in the near-wall region of a methane/air flame supported on a side-wall-quenching (SWQ) burner. Automatic temporal and spatial overlap of the ~7 femtosecond pump and Stokes pulses is achieved utilizing a two-beam CARS phase-matching scheme, and the crossed ~75 picosecond probe beam provide s excellent spatial sectioning of the probed location. Concurrent detection of N 2, O 2, H 2, CO, CO 2, and CH 4 is demonstrated while high-fidelity flame thermometry is assessed from the N 2 puremore » rotational S-branch in a one-dimensional -CARS imaging configuration. A methane/air premixed flame at lean, stoichiometric, and rich conditions ( Φ = 0.83, 1.0 , and 1.2) and Reynolds number = 5,000 is probed as it quenches against a cooled steel side- wall parallel to the flow providing a persistent flame-wall interaction. Here, an imaging resolution of better than 40 μm is achieved across the field -of-view, thus allowing thermochemical states (temperature and major species) of the thermal boundary layer to be resolved to within ~30 μm of the interface.« less

Early structural development in melt-quenched polymer PTT from atomistic molecular dynamic simulations

NASA Astrophysics Data System (ADS)

Hsieh, Min-Kang; Lin, Shiang-Tai

2009-12-01

Molecular dynamics simulations are performed to study the initial structural development in poly(trimethylene terephthalate) (PTT) when quenched below its melting point. The development of local ordering has been observed in our simulations. The thermal properties, such as the glass transition temperature (Tg) and the melting temperature (Tm), determined from our simulations are in reasonable agreement with experimental values. It is found that, between these two temperatures, the number of local structures quickly increases during the thermal relaxation period soon after the system is quenched and starts to fluctuate afterwards. The formation and development of local structures is found to be driven mainly by the torsional and van der Waals forces and follows the classical nucleation-growth mechanism. The variation of local structures' fraction with temperature exhibits a maximum between Tg and Tm, resembling the temperature dependence of the crystallization rate for most polymers. In addition, the backbone torsion distribution for segments within the local structures preferentially reorganizes to the trans-gauche-gauche-trans (t-g-g-t) conformation, the same as that in the crystalline state. As a consequence, we believe that such local structural ordering could be the baby nuclei that have been suggested to form in the early stage of polymer crystallization.

A preliminary study of the effect of equivalence ratio on a low emissions gas turbine combustor using KIVA-2

NASA Astrophysics Data System (ADS)

Yang, S. L.; Chen, R.; Cline, M. C.

The staged turbine combustor (STC) concept has drawn more and more attention since the late 70's because of its potential in reducing pollutant emissions where a high power output is required. A numerical study is performed to investigate the chemically reactive flow with sprays inside a STC combustor using a modified version of the KIVA-II code. This STC combustor consists of a fuel nozzle (FN), a rich-burn (RB) zone, a converging connecting section, a quick-quench (QQ) zone, a diverging connecting section, and a lean-combustion (LC) zone. An advanced airblast fuel nozzle, which has two fuel injection passages and four air flow passages for providing swirl, is used in this study. The effect of the equivalence ratio phi on the performance of the STC combustor is reported in this paper for phi range of 1.2 to 2.0. Preliminary results reveal some major features of the flow and temperature fields inside the STC combustor. Distributions of velocity, temperature, and some critical species information inside the FN/RB zone illustrate the effect of phi on the flame temperature and the NO(x) formation in rich burning. The co- and counter-rotating bulk flow, and the sandwiched-ring-shape temperature field in the QQ/LC zone, typical of the confined inclined jet-in-cross flow, are clearly shown from the computation. The predicted mass-weighted standard deviation and the pattern factor of temperature show that the mixing performance of the STC combustor is very good. The temperature of the fluid leaving the LC zone is very uniform. As expected. lower value of the emission index of NO can be achieved with larger value of phi. Prediction of the NO(x) emission shows that there is no excessive thermal NO(x) produced in the QQ/LC zone for all the cases studied.

Investigation of the impact of imposed air inlet velocity oscillations on the formation and oxidation of soot using simultaneous 2-Colour-TIRE-LII

NASA Astrophysics Data System (ADS)

Aleksandrov, A.; Suntz, R.; Bockhorn, H.

2015-05-01

The response of non-premixed swirling flames to acoustic perturbations at various frequencies (0-350 Hz) and the impact of imposed air inlet velocity oscillations on the formation and oxidation of soot are investigated. The results obtained from these flames are of special interest for "rich-quenched-lean" (RQL) combustion concepts applied in modern gas turbines. In RQL combustion, the fuel is initially oxidized by air under fuel-rich conditions in a first stage followed by a fuel-lean combustion step in a second stage. To mimic soot formation and oxidation in RQL combustion, soot particle measurements in highly turbulent, non-premixed swirling natural gas/ethylene-confined flames at imposed air inlet velocity oscillations are performed using simultaneous 2-Colour-Time-Resolved-Laser-Induced Incandescence (simultaneous 2-Colour-TIRE-LII). The latter technique is combined with line-of-sight averaged OH*-chemiluminescence imaging, measurements of the velocity field by high-speed particle imaging velocimetry under reactive combustion conditions and measurements of the mean temperature field obtained by a thermocouple. A natural gas/ethylene mixture (Φ = 1.56, 42 % C2H4, 58 % natural gas, P th = 17.6 kW at atmospheric pressure) is used as a fuel, which is oxidized by air under fuel-rich conditions in the first combustion chamber.

Afterburner Performance of Circular V-Gutters and a Sector of Parallel V-Gutters for a Range of Inlet Temperatures to 1255 K (1800 F)

NASA Technical Reports Server (NTRS)

Brandstetter, J. Robert; Reck, Gregory M.

1973-01-01

Combustion tests of two V-gutter types were conducted in a 19.25-in. diameter duct using vitiated air. Fuel spraybars were mounted in line with the V-gutters. Combustor length was set by flame-quench water sprays which were part of a calorimeter for measuring combustion efficiency. Although the levels of performance of the parallel and circular array afterburners were different, the trends with geometry variations were consistent. Therefore, parallel arrays can be used for evaluating V-gutter geometry effects on combustion performance. For both arrays, the highest inlet temperature produced combustion efficiencies near 100 percent. A 5-in. spraybar - to - V-gutter spacing gave higher efficiency and better lean blowout performance than a spacing twice as large. Gutter durability was good.

Strategies for laser-induced fluorescence detection of nitric oxide in high-pressure flames. II. A-X(0,1) excitation

NASA Astrophysics Data System (ADS)

Bessler, Wolfgang G.; Schulz, Christof; Lee, Tonghun; Jeffries, Jay B.; Hanson, Ronald K.

2003-04-01

A-X(0,1) excitation is a promising new approach for NO laser-induced fluorescence (LIF) diagnostics at elevated pressures and temperatures. We present what to our knowledge are the first detailed spectroscopic investigations within this excitation band using wavelength-resolved LIF measurements in premixed methane/air flames at pressures between 1 and 60 bar and a range of fuel/air ratios. Interference from O2 LIF is a significant problem in lean flames for NO LIF measurements, and pressure broadening and quenching lead to increased interference with increased pressure. Three different excitation schemes are identified that maximize NO/O2 LIF signal ratios, thereby minimizing the O2 interference. The NO LIF signal strength, interference by hot molecular oxygen, and temperature dependence of the three schemes are investigated.

Optical detection of organophosphorus compounds based on Mn-doped ZnSe d-dot enzymatic catalytic sensor.

PubMed

Gao, Xue; Tang, Guangchao; Su, Xingguang

2012-01-01

In this paper, we report a sensitive and selective method for detection of organophosphorus compounds (OPs) based on Mn:ZnSe d-dots-enzyme-hydrogen peroxide (H(2)O(2)) fluorescence quenching system. Acetylcholine esterase (AChE) can hydrolyze acetylcholine (ACh) to choline. Subsequently, choline oxidase (ChOx) oxidizes choline to generate H(2)O(2). The enzyme-generated H(2)O(2) can quench the fluorescence of Mn:ZnSe d-dots. When paraoxon are introduced in solution, it can interact with the active centers of AChE and decrease the enzyme activity. This leads to the decrease of the H(2)O(2) production and then the fluorescence quenching rate of Mn:ZnSe d-dots. Experimental results showed that the enzyme inhibition percentage of Mn:ZnSe d-dots-ChOx-AChE-ACh system was proportional to the logarithm of paraoxon in the range 4.84×10(-11) to 4.84×10(-6) mol/L with the detection limit (S/N=3) of 1.31×10(-11) mol/L. The proposed biosensor has been employed for quick determination of paraoxon in tap water and milk samples with satisfactory reproducibility and accuracy. This nano-biosensor was proved to be sensitive, rapid, simple and tolerance of most interfering substances. Copyright © 2012 Elsevier B.V. All rights reserved.

Development of an advanced Sabatier CO2 reduction subsystem

NASA Technical Reports Server (NTRS)

Kleiner, G. N.; Cusick, R. J.

1981-01-01

A preprototype Sabatier CO2 reduction subsystem was successfully designed, fabricated and tested. The lightweight, quick starting (less than 5 minutes) reactor utlizes a highly active and physically durable methanation catalyst composed of ruthenium on alumina. The use of this improved catalyst permits a simple, passively controlled reactor design with an average lean component H2/CO2 conversion efficiency of over 99% over a range of H2/CO2 molar ratios of 1.8 to 5 while operating with process flows equivalent to a crew size of up to five persons. The subsystem requires no heater operation after start-up even during simulated 55 minute lightside/39 minute darkside orbital operation.

A parametric numerical study of mixing in a cylindrical duct

NASA Astrophysics Data System (ADS)

Oechsle, V. L.; Mongia, H. C.; Holderman, J. D.

1992-07-01

The interaction is described of some of the important parameters affecting the mixing process in a quick mixing region of a rich burn/quick mix/lean burn (RQL) combustor. The performance of the quick mixing region is significantly affected by the geometric designs of both the mixing domain and the jet inlet orifices. Several of the important geometric parameters and operating conditions affecting the mixing process were analytically studied. Parameters such as jet-to-mainstream momentum flux ratio (J), mass flow ratio (MR), orifice geometry, orifice orientation, and number of orifices/row (equally spaced around the circumferential direction were analyzed. Three different sets of orifice shapes were studied: (1) square, (2) elongated slots, and (3) equilateral triangles. Based on the analytical results, the best mixing configuration depends significantly on the penetration depth of the jet to prevent the hot mainstream flow from being entrained behind the orifice. The structure in a circular mixing section is highly weighted toward the outer wall and any mixing structure affecting this area significantly affects the overall results. The increase in the number of orifices per row increases the mixing at higher J conditions. Higher slot slant angles and aspect ratios are generally the best mixing configurations at higher momentum flux ratio (J) conditions. However, the square and triangular shaped orifices were more effective mixing configurations at lower J conditions.

Cryogenic Quenching Process for Electronic Part Screening

NASA Technical Reports Server (NTRS)

Sheldon, Douglas J.; Cressler, John

2011-01-01

The use of electronic parts at cryogenic temperatures (less than 100 C) for extreme environments is not well controlled or developed from a product quality and reliability point of view. This is in contrast to the very rigorous and well-documented procedures to qualify electronic parts for mission use in the 55 to 125 C temperature range. A similarly rigorous methodology for screening and evaluating electronic parts needs to be developed so that mission planners can expect the same level of high reliability performance for parts operated at cryogenic temperatures. A formal methodology for screening and qualifying electronic parts at cryogenic temperatures has been proposed. The methodology focuses on the base physics of failure of the devices at cryogenic temperatures. All electronic part reliability is based on the bathtub curve, high amounts of initial failures (infant mortals), a long period of normal use (random failures), and then an increasing number of failures (end of life). Unique to this is the development of custom screening procedures to eliminate early failures at cold temperatures. The ability to screen out defects will specifically impact reliability at cold temperatures. Cryogenic reliability is limited by electron trap creation in the oxide and defect sites at conductor interfaces. Non-uniform conduction processes due to process marginalities will be magnified at cryogenic temperatures. Carrier mobilities change by orders of magnitude at cryogenic temperatures, significantly enhancing the effects of electric field. Marginal contacts, impurities in oxides, and defects in conductor/conductor interfaces can all be magnified at low temperatures. The novelty is the use of an ultra-low temperature, short-duration quenching process for defect screening. The quenching process is designed to identify those defects that will precisely (and negatively) affect long-term, cryogenic part operation. This quenching process occurs at a temperature that is at least 25 C colder than the coldest expected operating temperature. This quenching process is the opposite of the standard burn-in procedure. Normal burn-in raises the temperature (and voltage) to activate quickly any possible manufacturing defects remaining in the device that were not already rejected at a functional test step. The proposed inverse burn-in or quenching process is custom-tailored to the electronic device being used. The doping profiles, materials, minimum dimensions, interfaces, and thermal expansion coefficients are all taken into account in determining the ramp rate, dwell time, and temperature.

Android subcutaneous adipose tissue topography in lean and obese women suffering from PCOS: comparison with type 2 diabetic women.

PubMed

Horejsi, R; Möller, R; Rackl, S; Giuliani, A; Freytag, U; Crailsheim, K; Sudi, K; Tafeit, E

2004-07-01

The new optical device, the lipometer, enables the noninvasive, quick, safe, and precise determination of the thickness of subcutaneous adipose tissue (SAT) layers at any given site of the human body. Fifteen anatomically well-defined body sites from neck to calf describe a SAT topography (SAT-Top) like an individual "fingerprint" of a subject. This SAT-Top was examined in 16 women with polycystic ovary syndrome (PCOS) and compared to the body fat distribution of 87 age-matched healthy controls and 20 type-2 diabetic women. SAT-Top differences of these three groups were described and, to render the possibility of visual comparison, the 15-dimensional body fat information was condensed to a two-dimensional factor plot by factor analysis. All PCOS patients had an android body fat distribution with significantly thinner SAT layers on the legs as compared to healthy controls. Moreover, a hierarchical cluster analysis resulted in two distinctly different groups of PCOS women, a lean (PCOSL) and an obese (PCOSO) cluster: compared to healthy women, lean PCOS patients had significantly lower total SAT development, even though height, weight, and body mass index did not deviate significantly. Especially on the legs, their SAT layers were significantly lowered, indicating a more "apple-like" fat distribution type. Obese PCOS women showed a SAT-Top pattern very similar to that of women with type-2 diabetes, although the mean age difference between these groups was more than 30 years. Compared to healthy controls, the SAT-Top of these obese PCOS patients was strongly shifted into the android direction, appearing as "super-apples" with a significantly increased upper trunk obesity to 237.8% and a significantly decreased leg SAT development to 79.8%. Copyright 2004 Wiley-Liss, Inc.

Nanostructured biosensor for detecting glucose in tear by applying fluorescence resonance energy transfer quenching mechanism.

PubMed

Chen, Longyi; Tse, Wai Hei; Chen, Yi; McDonald, Matthew W; Melling, James; Zhang, Jin

2017-05-15

In this paper, a nanostructured biosensor is developed to detect glucose in tear by using fluorescence resonance energy transfer (FRET) quenching mechanism. The designed FRET pair, including the donor, CdSe/ZnS quantum dots (QDs), and the acceptor, dextran-binding malachite green (MG-dextran), was conjugated to concanavalin A (Con A), an enzyme with specific affinity to glucose. In the presence of glucose, the quenched emission of QDs through the FRET mechanism is restored by displacing the dextran from Con A. To have a dual-modulation sensor for convenient and accurate detection, the nanostructured FRET sensors were assembled onto a patterned ZnO nanorod array deposited on the synthetic silicone hydrogel. Consequently, the concentration of glucose detected by the patterned sensor can be converted to fluorescence spectra with high signal-to-noise ratio and calibrated image pixel value. The photoluminescence intensity of the patterned FRET sensor increases linearly with increasing concentration of glucose from 0.03mmol/L to 3mmol/L, which covers the range of tear glucose levels for both diabetics and healthy subjects. Meanwhile, the calibrated values of pixel intensities of the fluorescence images captured by a handhold fluorescence microscope increases with increasing glucose. Four male Sprague-Dawley rats with different blood glucose concentrations were utilized to demonstrate the quick response of the patterned FRET sensor to 2µL of tear samples. Copyright © 2016 Elsevier B.V. All rights reserved.

Towards the Development of a Low-Cost Device for the Detection of Explosives Vapors by Fluorescence Quenching of Conjugated Polymers in Solid Matrices.

PubMed

Martelo, Liliana M; das Neves, Tiago F Pimentel; Figueiredo, João; Marques, Lino; Fedorov, Alexander; Charas, Ana; Berberan-Santos, Mário N; Burrows, Hugh D

2017-11-03

Conjugated polymers (CPs) have proved to be promising chemosensory materials for detecting nitroaromatic explosives vapors, as they quickly convert a chemical interaction into an easily-measured high-sensitivity optical output. The nitroaromatic analytes are strongly electron-deficient, whereas the conjugated polymer sensing materials are electron-rich. As a result, the photoexcitation of the CP is followed by electron transfer to the nitroaromatic analyte, resulting in a quenching of the light-emission from the conjugated polymer. The best CP in our studies was found to be poly[(9,9-dioctylfluorenyl-2,7-diyl)-co-bithiophene] (F8T2). It is photostable, has a good absorption between 400 and 450 nm, and a strong and structured fluorescence around 550 nm. Our studies indicate up to 96% quenching of light-emission, accompanied by a marked decrease in the fluorescence lifetime, upon exposure of the films of F8T2 in ethyl cellulose to nitrobenzene (NB) and 1,3-dinitrobenzene (DNB) vapors at room temperature. The effects of the polymeric matrix, plasticizer, and temperature have been studied, and the morphology of films determined by scanning electron microscopy (SEM) and confocal fluorescence microscopy. We have used ink jet printing to produce sensor films containing both sensor element and a fluorescence reference. In addition, a high dynamic range, intensity-based fluorometer, using a laser diode and a filtered photodiode was developed for use with this system.

A Rapid and Sensitive Strip-Based Quick Test for Nerve Agents Tabun, Sarin, and Soman Using BODIPY-Modified Silica Materials.

PubMed

Climent, Estela; Biyikal, Mustafa; Gawlitza, Kornelia; Dropa, Tomáš; Urban, Martin; Costero, Ana M; Martínez-Máñez, Ramón; Rurack, Knut

2016-08-01

Test strips that in combination with a portable fluorescence reader or digital camera can rapidly and selectively detect chemical warfare agents (CWAs) such as Tabun (GA), Sarin (GB), and Soman (GD) and their simulants in the gas phase have been developed. The strips contain spots of a hybrid indicator material consisting of a fluorescent BODIPY indicator covalently anchored into the channels of mesoporous SBA silica microparticles. The fluorescence quenching response allows the sensitive detection of CWAs in the μg m(-3) range in a few seconds. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Molecular dynamics simulations of the structure evolutions of Cu-Zr metallic glasses under irradiation

NASA Astrophysics Data System (ADS)

Lang, Lin; Tian, Zean; Xiao, Shifang; Deng, Huiqiu; Ao, Bingyun; Chen, Piheng; Hu, Wangyu

2017-02-01

Molecular dynamics simulations have been performed to investigate the structural evolution of Cu64.5Zr35.5 metallic glasses under irradiation. The largest standard cluster analysis (LSCA) method was used to quantify the microstructure within the collision cascade regions. It is found that the majority of clusters within the collision cascade regions are full and defective icosahedrons. Not only the smaller structures (common neighbor subcluster) but also primary clusters greatly changed during the collision cascades; while most of these radiation damages self-recover quickly in the following quench states. These findings indicate the Cu-Zr metallic glasses have excellent irradiation-resistance properties.

Sulfation of K-based Lean NOx Trap while Cycling Between Lean and Rich Conditions: I. Microreactor Study

DOE Office of Scientific and Technical Information (OSTI.GOV)

Toops, Todd J; Pihl, Josh A

2008-01-01

Exposure of Pt/K/Al{sub 2}O{sub 3} to 15 ppm SO{sub 2} reduces the NOx activity at 200, 300, and 400 C at significantly different rates--1.5, 8.5, and 18.0 {micro}mol NOx/(h g{sub cat}), respectively. During the initial sulfation, NOx conversion is directly linked to lean phase storage capacity, and sulfation does not impact the reduction kinetics since the amount of unconverted NOx was constant or decreased with increasing sulfation time. A portion of sulfur stored at 200 C desorbs upon mild heating to 400 C while cycling between lean and rich conditions. This apparently is a result of sulfur being released frommore » Al{sub 2}O{sub 3}; however, performance is not significantly recovered as much of the sulfur is re-adsorbed on the K-phase. This is apparent from analysis of the NOx storage and release profiles. Additional analysis of these profiles suggests that SO{sub 2} initially adsorbs near Pt before interacting with other sites further away from Pt at 300 C. At 400 C, it appears that SO{sub 2} either preferentially adsorbs near Pt and then quickly diffuses along the surface to other less proximal sites, or it directly adsorbs on sites further away from Pt. De-sulfurization up to 800 C using a temperature programmed reduction (TPR) procedure and rich conditions with both CO{sub 2} and H{sub 2}O restored 73=94% of the LNT performance at 300 and 400 C. However, the recovered performance measured at 200 C was only 34-49% of the original NOx reduction activity. H{sub 2}S and SO{sub 2} were the primary de-sulfurization products with H{sub 2}S having a maximum release between 690 and 755 C, while SO{sub 2} had a peak release between 770 and 785 C. The sulfation temperature does not have a significant impact on the recovered performance, the de-sulfurization products or the sulfur release temperature.« less

Low Emission Hydrogen Combustors for Gas Turbines Using Lean Direct Injection

NASA Technical Reports Server (NTRS)

Marek, C. John; Smith, Timothy D.; Kundu, Krishna

2005-01-01

One of the key technology challenges for the use of hydrogen in gas turbine engines is the performance of the combustion system, in particular the fuel injectors. To investigate the combustion performance of gaseous hydrogen fuel injectors flame tube combustor experiments were performed. Tests were conducted to measure the nitrogen oxide (NOx) emissions and combustion performance at inlet conditions of 600 to 1000 deg F, 60 to 200 pounds per square inch absolute (psia), and equivalence ratios up to 0.48. All the injectors were based on Lean Direct Injection (LDI) technology with multiple injection points and quick mixing. One challenge to hydrogen based premixing combustion systems is flashback since hydrogen has a reaction rate over seven times that of Jet-A. To reduce the risk, design mixing times were kept short and velocities high to minimize flashback. Five fuel injector designs were tested in 2.5 and 3.5-in. diameter flame tubes with non-vitiated heated air and gaseous hydrogen. Data is presented on measurements of NOx emissions and combustion efficiency for the hydrogen injectors at 1.0, 3.125, and 5.375 in. from the injector face. Results show that for some configurations, NOx emissions are comparable to that of state of the art Jet-A LDI combustor concepts.

Low-Emission Hydrogen Combustors for Gas Turbines Using Lean Direct Injection

NASA Technical Reports Server (NTRS)

Marek, C. John; Smith, Timothy D.; Kundu, Krishna

2007-01-01

One of the key technology challenges for the use of hydrogen in gas turbine engines is the performance of the combustion system, in particular the fuel injectors. To investigate the combustion performance of gaseous hydrogen fuel injectors flame tube combustor experiments were performed. Tests were conducted to measure the nitrogen oxide (NO(x)) emissions and combustion performance at inlet conditions of 588 to 811 K, 0.4 to 1.4 MPa, and equivalence ratios up to 0.48. All the injectors were based on Lean Direct Injection (LDI) technology with multiple injection points and quick mixing. One challenge to hydrogen-based premixing combustion systems is flashback since hydrogen has a reaction rate over 7 times that of Jet-A. To reduce the risk, design mixing times were kept short and velocities high to minimize flashback. Five fuel injector designs were tested in 6.35- and 8.9-cm-diameter flame tubes with non-vitiated heated air and gaseous hydrogen. Data is presented on measurements of NO(x) emissions and combustion efficiency for the hydrogen injectors at 2.540, 7.937, and 13.652 cm from the injector face. Results show that for some configurations, NO(x) emissions are comparable to that of state of the art Jet-A LDI combustor concepts.

Microgravity Flammability of PMMA Rods in Concurrent Flow

NASA Technical Reports Server (NTRS)

Olson, Sandra L.; Ferkul, Paul V.

2015-01-01

Microgravity experiments burning cast PMMA cylindrical rods in axial flow have been conducted aboard the International Space Station in the Microgravity Science Glovebox (MSG) facility using the Burning and Suppression of Solids (BASS) flow duct, as part of the BASS-II experiment. Twenty-four concurrent-flow tests were performed, focusing on finding flammability limits as a function of oxygen and flow speed. The oxygen was varied by using gaseous nitrogen to vitiate the working volume of the MSG. The speed of the flow parallel to the rod was varied using a fan at the entrance to the duct. Both blowoff and quenching limits were obtained at several oxygen concentrations. Each experiment ignited the rod at the initially hemispherical stagnation tip of the rod, and allowed the flame to develop and heat the rod at a sufficient flow to sustain burning. For blowoff limit tests, the astronaut quickly turned up the flow to obtain extinction. Complementary 5.18-second Zero Gravity Facility drop tests were conducted to compare blowoff limits in short and long duration microgravity. For quenching tests, the flow was incrementally turned down and the flame allowed to stabilize at the new flow condition for at least the solid-phase response time before changing it again. Quenching was observed when the flow became sufficiently weak that the flame could no longer provide adequate heat flux to compensate for the heat losses (conduction into the rod and radiation). A surface energy balance is presented that shows the surface radiative loss exceeds the conductive loss into the rod near the limit. The flammability boundary is shown to represent a critical Damkohler number, expressed in terms of the reaction rate divided by the stretch rate. For the blowoff branch, the boundary exhibits a linear dependence on oxygen concentration and stretch rate, indicating that the temperature at blowoff must be fairly constant. For the quenching branch, the dominance of the exponential nature of the Arrhenius kinetics reaction rate indicates that the temperature is critical.

Trace Detection of RDX, HMX and PETN Explosives Using a Fluorescence Spot Sensor

PubMed Central

Wang, Chen; Huang, Helin; Bunes, Benjamin R.; Wu, Na; Xu, Miao; Yang, Xiaomei; Yu, Li; Zang, Ling

2016-01-01

1,3,5-trinitroperhydro-1,3,5-triazine (RDX), octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX), and pentaerythritol tetranitrate (PETN), the major components in plastic explosives, pose a significant threat to public safety. A quick, sensitive, and low-cost detection method for these non-volatile explosives is eagerly demanded. Here we present a fluo-spot approach, which can be employed for in situ detection of trace amount of explosives. The sensor molecule is a charge-transfer fluorophore, DCM, which is strongly fluorescent in its pristine state, but non-fluorescent after the quick reaction with NO2· (or NO2+) generated from the UV photolysis of RDX, HMX (or PETN). When fabricated within silica gel TLC plate, the fluo-spot sensor features high sensitivity owing to the large surface area and porous structure of the substrate. The sensor reaction mechanism was verified by various experimental characterizations, including chromatography, UV-Vis absorption and fluorescence spectroscopy, MS and 1H NMR spectrometry. The fluo-spot also demonstrated high selectivity towards RDX, HMX and PETN, as no significant fluorescence quenching was observed for other chemical compounds including common nitro-aromatic explosives and inorganic oxidative compounds. The DCM sensor can also be used as an economical spray kit to directly spot the explosives by naked eyes, implying great potential for quick, low-cost trace explosives detection. PMID:27146290

Trace Detection of RDX, HMX and PETN Explosives Using a Fluorescence Spot Sensor.

PubMed

Wang, Chen; Huang, Helin; Bunes, Benjamin R; Wu, Na; Xu, Miao; Yang, Xiaomei; Yu, Li; Zang, Ling

2016-05-05

1,3,5-trinitroperhydro-1,3,5-triazine (RDX), octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX), and pentaerythritol tetranitrate (PETN), the major components in plastic explosives, pose a significant threat to public safety. A quick, sensitive, and low-cost detection method for these non-volatile explosives is eagerly demanded. Here we present a fluo-spot approach, which can be employed for in situ detection of trace amount of explosives. The sensor molecule is a charge-transfer fluorophore, DCM, which is strongly fluorescent in its pristine state, but non-fluorescent after the quick reaction with NO2· (or NO2(+)) generated from the UV photolysis of RDX, HMX (or PETN). When fabricated within silica gel TLC plate, the fluo-spot sensor features high sensitivity owing to the large surface area and porous structure of the substrate. The sensor reaction mechanism was verified by various experimental characterizations, including chromatography, UV-Vis absorption and fluorescence spectroscopy, MS and (1)H NMR spectrometry. The fluo-spot also demonstrated high selectivity towards RDX, HMX and PETN, as no significant fluorescence quenching was observed for other chemical compounds including common nitro-aromatic explosives and inorganic oxidative compounds. The DCM sensor can also be used as an economical spray kit to directly spot the explosives by naked eyes, implying great potential for quick, low-cost trace explosives detection.

Thermalization dynamics in a quenched many-body state

NASA Astrophysics Data System (ADS)

Kaufman, Adam; Preiss, Philipp; Tai, Eric; Lukin, Alex; Rispoli, Matthew; Schittko, Robert; Greiner, Markus

2016-05-01

Quantum and classical many-body systems appear to have disparate behavior due to the different mechanisms that govern their evolution. The dynamics of a classical many-body system equilibrate to maximally entropic states and quickly re-thermalize when perturbed. The assumptions of ergodicity and unbiased configurations lead to a successful framework of describing classical systems by a sampling of thermal ensembles that are blind to the system's microscopic details. By contrast, an isolated quantum many-body system is governed by unitary evolution: the system retains memory of past dynamics and constant global entropy. However, even with differing characteristics, the long-term behavior for local observables in quenched, non-integrable quantum systems are often well described by the same thermal framework. We explore the onset of this convergence in a many-body system of bosonic atoms in an optical lattice. Our system's finite size allows us to verify full state purity and measure local observables. We observe rapid growth and saturation of the entanglement entropy with constant global purity. The combination of global purity and thermalized local observables agree with the Eigenstate Thermalization Hypothesis in the presence of a near-volume law in the entanglement entropy.

Interaction of turbulent premixed flames with combustion products: Role of stoichiometry

DOE Office of Scientific and Technical Information (OSTI.GOV)

Coriton, Bruno Rene Leon; Frank, Jonathan H.; Gomez, Alessandro

Stabilization methods of turbulent flames often involve mixing of reactants with hot products of combustion. The stabilizing effect of combustion product enthalpy has been long recognized, but the role played by the chemical composition of the product gases is typically overlooked. We employ a counterflow system to pinpoint the effects of the combustion product stoichiometry on the structure of turbulent premixed flames under conditions of both stable burning and local extinction. To that end, a turbulent jet of lean-to-rich, CH 4/O 2/N 2-premixed reactants at a turbulent Reynolds number of 1050 was opposed to a stream of hot products ofmore » combustion that were generated in a preburner. While the combustion product stream temperature was kept constant, its stoichiometry was varied independently from that of the reactant stream, leading to reactant-to-product stratification of relevance to practical combustion systems. The detailed structure of the turbulent flame front was analyzed in two series of experiments using laser-induced fluorescence (LIF): joint CH 2O LIF and OH LIF measurements and joint CO LIF and OH LIF measurements. Results revealed that a decrease in local CH 2O+OH and CO+OH reaction rates coincide with the depletion of OH radicals in the vicinity of the combustion product stream. These critical combustion reaction rates were more readily quenched in the presence of products of combustion from a stoichiometric flame, whereas they were favored by lean combustion products. As a result, stoichiometric combustion products contributed to a greater occurrence of local extinction. Furthermore, they limited the capacity of premixed reactants to ignite and of the turbulent premixed flames to stabilize. In contrast, lean and rich combustion products facilitated flame ignition and stability and reduced the rate of local extinction. The influence of the combustion product stream on the turbulent flame front was limited to a zone of approximately two millimeters from the gas mixing layer interface (GMLI) of the product stream. As a result, flame fronts that were separated from the GMLI by larger distances were unaffected by the product stream stoichiometry.« less

Interaction of turbulent premixed flames with combustion products: Role of stoichiometry

DOE PAGES

Coriton, Bruno Rene Leon; Frank, Jonathan H.; Gomez, Alessandro

2016-05-30

Stabilization methods of turbulent flames often involve mixing of reactants with hot products of combustion. The stabilizing effect of combustion product enthalpy has been long recognized, but the role played by the chemical composition of the product gases is typically overlooked. We employ a counterflow system to pinpoint the effects of the combustion product stoichiometry on the structure of turbulent premixed flames under conditions of both stable burning and local extinction. To that end, a turbulent jet of lean-to-rich, CH 4/O 2/N 2-premixed reactants at a turbulent Reynolds number of 1050 was opposed to a stream of hot products ofmore » combustion that were generated in a preburner. While the combustion product stream temperature was kept constant, its stoichiometry was varied independently from that of the reactant stream, leading to reactant-to-product stratification of relevance to practical combustion systems. The detailed structure of the turbulent flame front was analyzed in two series of experiments using laser-induced fluorescence (LIF): joint CH 2O LIF and OH LIF measurements and joint CO LIF and OH LIF measurements. Results revealed that a decrease in local CH 2O+OH and CO+OH reaction rates coincide with the depletion of OH radicals in the vicinity of the combustion product stream. These critical combustion reaction rates were more readily quenched in the presence of products of combustion from a stoichiometric flame, whereas they were favored by lean combustion products. As a result, stoichiometric combustion products contributed to a greater occurrence of local extinction. Furthermore, they limited the capacity of premixed reactants to ignite and of the turbulent premixed flames to stabilize. In contrast, lean and rich combustion products facilitated flame ignition and stability and reduced the rate of local extinction. The influence of the combustion product stream on the turbulent flame front was limited to a zone of approximately two millimeters from the gas mixing layer interface (GMLI) of the product stream. As a result, flame fronts that were separated from the GMLI by larger distances were unaffected by the product stream stoichiometry.« less

P and W propulsion systems studies results/status

NASA Technical Reports Server (NTRS)

Smith, Martin G., Jr.; Champagne, George A.

1992-01-01

The topics covered include the following: Pratt and Whitney (P&W) propulsion systems studies - NASA funded efforts to date; P&W engine concepts; P&W combustor focus - rich burn quick quench (RBQQ) concept; mixer ejector nozzle concept - large flow entrainment reduces jet noise; technology impact on NO(x) emissions - mature RBQQ combustor reduces NO(x) up to 85 percent; technology impact on sideline noise characteristics of Mach 2.4 turbine bypass engines (TBE's) - 600 lb/sec airflow size; technology impact on takeoff gross weight (TOGW) - provides up to 12 percent TOGW reduction; HSCT quiet engine concepts; TBE inlet valve/ejector nozzle concept schematic; mixed flow turbofan study; and exhaust nozzle conceptual design.

Coal combustion system

DOEpatents

Wilkes, Colin; Mongia, Hukam C.; Tramm, Peter C.

1988-01-01

In a coal combustion system suitable for a gas turbine engine, pulverized coal is transported to a rich zone combustor and burned at an equivalence ratio exceeding 1 at a temperature above the slagging temperature of the coal so that combustible hot gas and molten slag issue from the rich zone combustor. A coolant screen of water stretches across a throat of a quench stage and cools the combustible gas and molten slag to below the slagging temperature of the coal so that the slag freezes and shatters into small pellets. The pelletized slag is separated from the combustible gas in a first inertia separator. Residual ash is separated from the combustible gas in a second inertia separator. The combustible gas is mixed with secondary air in a lean zone combustor and burned at an equivalence ratio of less than 1 to produce hot gas motive at temperature above the coal slagging temperature. The motive fluid is cooled in a dilution stage to an acceptable turbine inlet temperature before being transported to the turbine.

Predictive Model Development for Aviation Black Carbon Mass Emissions from Alternative and Conventional Fuels at Ground and Cruise.

PubMed

Abrahamson, Joseph P; Zelina, Joseph; Andac, M Gurhan; Vander Wal, Randy L

2016-11-01

The first order approximation (FOA3) currently employed to estimate BC mass emissions underpredicts BC emissions due to inaccuracies in measuring low smoke numbers (SNs) produced by modern high bypass ratio engines. The recently developed Formation and Oxidation (FOX) method removes the need for and hence uncertainty associated with (SNs), instead relying upon engine conditions in order to predict BC mass. Using the true engine operating conditions from proprietary engine cycle data an improved FOX (ImFOX) predictive relation is developed. Still, the current methods are not optimized to estimate cruise emissions nor account for the use of alternative jet fuels with reduced aromatic content. Here improved correlations are developed to predict engine conditions and BC mass emissions at ground and cruise altitude. This new ImFOX is paired with a newly developed hydrogen relation to predict emissions from alternative fuels and fuel blends. The ImFOX is designed for rich-quench-lean style combustor technologies employed predominately in the current aviation fleet.

Staged direct injection diesel engine

DOEpatents

Baker, Quentin A.

1985-01-01

A diesel engine having staged injection for using lower cetane number fuels than No. 2 diesel fuel. The engine includes a main fuel injector and a pilot fuel injector. Pilot and main fuel may be the same fuel. The pilot injector injects from five to fifteen percent of the total fuel at timings from 20.degree. to 180.degree. BTDC depending upon the quantity of pilot fuel injected, the fuel cetane number and speed and load. The pilot fuel injector is directed toward the centerline of the diesel cylinder and at an angle toward the top of the piston, avoiding the walls of the cylinder. Stratification of the early injected pilot fuel is needed to reduce the fuel-air mixing rate, prevent loss of pilot fuel to quench zones, and keep the fuel-air mixture from becoming too fuel lean to become effective. In one embodiment, the pilot fuel injector includes a single hole for injection of the fuel and is directed at approximately 48.degree. below the head of the cylinder.

Quick-Mixing Studies Under Reacting Conditions

NASA Technical Reports Server (NTRS)

Leong, May Y.; Samuelsen, G. S.

1996-01-01

The low-NO(x) emitting potential of rich-burn/quick-mix/lean-burn )RQL) combustion makes it an attractive option for engines of future stratospheric aircraft. Because NO(x) formation is exponentially dependent on temperature, the success of the RQL combustor depends on minimizing high temperature stoichiometric pocket formation in the quick-mixing section. An experiment was designed and built, and tests were performed to characterize reaction and mixing properties of jets issuing from round orifices into a hot, fuel-rich crossflow confined in a cylindrical duct. The reactor operates on propane and presents a uniform, non-swirling mixture to the mixing modules. Modules consisting of round orifice configurations of 8, 9, 10, 12, 14, and 18 holes were evaluated at a momentum-flux ratio of 57 and jet-to-mainstream mass-flaw ratio of 2.5. Temperatures and concentrations of O2, CO2, CO, HC, and NO(x) were obtained upstream, down-stream, and within the orifice plane to determine jet penetration as well as reaction processes. Jet penetration was a function of the number of orifices and affected the mixing in the reacting system. Of the six configurations tested, the 14-hole module produced jet penetration close to the module half-radius and yielded the best mixing and most complete combustion at a plane one duct diameter from the orifice leading edge. The results reveal that substantial reaction and heat release occur in the jet mixing zone when the entering effluent is hot and rich, and that the experiment as designed will serve to explore satisfactorily jet mixing behavior under realistic reacting conditions in future studies.

Ares Launch Vehicles Lean Practices Case Study

NASA Technical Reports Server (NTRS)

Doreswamy, Rajiv, N.; Self, Timothy A.

2008-01-01

This viewgraph presentation describes test strategies and lean philisophies and practices that are applied to Ares Launch Vehicles. The topics include: 1) Testing strategy; 2) Lean Practices in Ares I-X; 3) Lean Practices Applied to Ares I-X Schedule; 4) Lean Event Results; 5) Lean, Six Sigma, and Kaizen Practices in the Ares Projects Office; 6) Lean and Kaizen Success Stories; and 7) Ares Six Sigma Practices.

Risk of Disordered Eating Among Division I Female College Athletes

PubMed Central

WELLS, ELIZABETH K.; CHIN, ALEXANDRA D.; TACKE, JENNIFER A.; BUNN, JENNIFER A.

2015-01-01

The purpose of this study was to assess the risk of disordered eating (DE) among female athletes in lean and non-lean sports using the ATHLETE survey. The ATHLETE survey is divided into six different constructs, and a high score indicates a high risk for DE. Eighty-three varsity female athletes from eight Campbell University sports teams completed the survey and a medical history form anonymously. The sports were divided into sports that traditionally have a high risk for DE (lean sports) and those with a low risk (non-lean sports). The lean sports included: cheerleading, cross country/track and field, swimming, and volleyball. The non-lean sports included: basketball, golf, soccer, and softball. The total mean score of the ATHLETE survey for the lean sports was 100.1 ± 17.4, compared to the non-lean sports scoring 90.1 ± 16.9, p = 0.011. The two constructs that showed significant difference between lean and non-lean sports were Social Pressure on Body Shape (lean: 12.2 ± 3.9, non-lean: 9.4 ± 4.6, p = 0.005) and Team Trust (lean: 7.4 ± 3.3, non-lean: 5.6 ± 2.2, p = 0.004). The results indicate that lean sports exhibited a higher risk for development of DE compared to athletes participating in non-lean sports. It appears that the primary influence of DE in these female athletes came from external social pressures that may therefore dictate their exercise and nutritional habits. PMID:27293502

Evaluating Lean in healthcare.

PubMed

Burgess, Nicola; Radnor, Zoe

2013-01-01

The purpose of this paper is to present findings relating to how Lean is implemented in English hospitals. Lean implementation snapshots in English hospitals were conducted by content analysing all annual reports and web sites over two time periods, giving a thorough analysis of Lean's status in English healthcare. The article identifies divergent approaches to Lean implementation in English hospitals. These approaches are classified into a typology to facilitate an evaluation of how Lean is implemented. The findings suggest that implementation tends to be isolated rather than system-wide. A second dataset conveys Lean implementation trajectory across the time period. These data signal Lean's increasing use by English hospitals and shows progression towards an increasingly systemic approach. Data were collected using content analysis methods, which relies on how "Lean" methods were articulated within the annual report and/or on the organisation's web site, which indicates approaches taken by hospital staff implementing Lean. This research is the first to examine more closely "how" Lean is implemented in English hospitals. The emergent typology could prove relevant to other public sector organizations and service organisations more generally. The research also presents a first step to understanding Lean thinking in the English NHS. This article empirically analyses Lean implementation in English hospitals. It identifies divergent approaches that allow inferences about how far Lean is implemented in an organisation. Data represent a baseline for further analysis so that Lean implementation can be tracked.

What Is Lean Management in Health Care? Development of an Operational Definition for a Cochrane Systematic Review.

PubMed

Rotter, Thomas; Plishka, Christopher; Lawal, Adegboyega; Harrison, Liz; Sari, Nazmi; Goodridge, Donna; Flynn, Rachel; Chan, James; Fiander, Michelle; Poksinska, Bonnie; Willoughby, Keith; Kinsman, Leigh

2018-01-01

Industrial improvement approaches such as Lean management are increasingly being adopted in health care. Synthesis is necessary to ensure these approaches are evidence based and requires operationalization of concepts to ensure all relevant studies are included. This article outlines the process utilized to develop an operational definition of Lean in health care. The literature search, screening, data extraction, and data synthesis processes followed the recommendations outlined by the Cochrane Collaboration. Development of the operational definition utilized the methods prescribed by Kinsman et al. and Wieland et al. This involved extracting characteristics of Lean, synthesizing similar components to establish an operational definition, applying this definition, and updating the definition to address shortcomings. We identified two defining characteristics of Lean health-care management: (1) Lean philosophy, consisting of Lean principles and continuous improvement, and (2) Lean activities, which include Lean assessment activities and Lean improvement activities. The resulting operational definition requires that an organization or subunit of an organization had integrated Lean philosophy into the organization's mandate, guidelines, or policies and utilized at least one Lean assessment activity or Lean improvement activity. This operational definition of Lean management in health care will act as an objective screening criterion for our systematic review. To our knowledge, this is the first evidence-based operational definition of Lean management in health care.

Antecedents and characteristics of lean thinking implementation in a Swedish hospital: a case study.

PubMed

Ulhassan, Waqar; Sandahl, Christer; Westerlund, Hugo; Henriksson, Peter; Bennermo, Marie; von Thiele Schwarz, Ulrica; Thor, Johan

2013-01-01

Despite the reported success of Lean in health care settings, it is unclear why and how organizations adopt Lean and how Lean transforms work design and, in turn, affects employees' work. This study investigated a cardiology department's journey to adopt and adapt Lean. The investigation was focused on the rationale and evolution of the Lean adoption to illuminate how a department with a long quality improvement history arrived at the decision to introduce Lean, and how Lean influenced employees' daily work. This is an explanatory single case study based on semistructured interviews, nonparticipant observations, and document studies. Guided by a Lean model, we undertook manifest content analysis of the data. We found that previous improvement efforts may facilitate the introduction of Lean but may be less important when forecasting whether Lean will be sustained over time. Contextual factors seemed to influence both what Lean tools were implemented and how well the changes were sustained. For example, adoption of Lean varied with the degree to which staff saw a need for change. Work redesign and teamwork were found helpful to improve patient care whereas problem solving was found helpful in keeping the staff engaged and sustaining the results over time.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rangaraj, D; Chan, K; Boddu, S

Lean thinking has revolutionized the manufacturing industry. Toyota has pioneered and leveraged this aspect of Lean thinking. Application of Lean thinking and Lean Six Sigma techniques into Healthcare and in particular in Radiation Oncology has its merits and challenges. To improve quality, safety and patient satisfaction with available resources or reducing cost in terms of time, staff and resources is demands of today's healthcare. Radiation oncology treatment involves many processes and steps, identifying and removing the non-value added steps in a process can significantly improve the efficiency. Real projects undertaken in radiation oncology department in cutting down the procedure timemore » for MRI guided brachytherapy to 40% less using lean thinking will be narrated. Simple Lean tools and techniques such as Gemba walk, visual control, daily huddles, standard work, value stream mapping, error-proofing, etc. can be applied with existing resources and how that improved the operation in a Radiation Oncology department's two year experience will be discussed. Lean thinking focuses on identifying and solving the root-cause of a problem by asking “Why” and not “Who” and this requires a culture change of no blame. Role of leadership in building lean culture, employee empowerment and trains and develops lean thinkers will be presented. Why Lean initiatives fail and how to implement lean successfully in your clinic will be discussed. Learning Objectives: Concepts of lean management or lean thinking. Lean tools and techniques applied in Radiation Oncology. Implement no blame culture and focus on system and processes. Leadership role in implementing lean culture. Challenges for Lean thinking in healthcare.« less

Quantitative PLIF Imaging in High-Pressure Combustion

NASA Technical Reports Server (NTRS)

Hanson, R. K.

1997-01-01

This is the final report for a research project aimed at developing planar laser-induced fluorescence (PLIF) techniques for quantitative 2-D species imaging in fuel-lean, high-pressure combustion gases, relevant to modem aircraft gas turbine combustors. The program involved both theory and experiment. The theoretical activity led to spectroscopic models that allow calculation of the laser-induced fluorescence produced in OH, NO and 02 for arbitrary excitation wavelength, pressure, temperature, gas mixture and laser linewidth. These spectroscopic models incorporate new information on line- broadening, energy transfer and electronic quench rates. Extensive calculations have been made with these models in order to identify optimum excitation strategies, particularly for detecting low levels (ppm) of NO in the presence of large 02 mole fractions (10% is typical for the fuel-lean combustion of interest). A promising new measurement concept has emerged from these calculations, namely that excitation at specific wavelengths, together with detection of fluorescence in multiple spectral bands, promises to enable simultaneous detection of both NO (at ppm levels) and 02 or possibly NO, 02 and temperature. Calculations have been made to evaluate the expected performance of such a diagnostic for a variety of conditions and choices of excitation and detection wavelengths. The experimental effort began with assembly of a new high-pressure combustor to provide controlled high-temperature and high-pressure combustion products. The non-premixed burner enables access to postflame gases at high temperatures (to 2000 K) and high pressures (to 13 atm), and a range of fuel-air equivalence ratios. The chamber also allowed use of a sampling probe, for chemiluminescent detection of NO/NO2, and thermocouples for measurement of gas temperature. Experiments were conducted to confirm the spectroscopic models for OH, NO and 02.

Flow Coupling Effects in Jet-in-Crossflow Flowfields

NASA Technical Reports Server (NTRS)

Bain, D. B.; Smith, C. E.; Liscinsky, D. S.; Holdeman, J. D.

1996-01-01

The combustor designer is typically required to design liner orifices that effectively mix air jets with crossflow effluent. CFD combustor analysis is typically used in the design process; however the jets are usually assumed to enter the combustor with a uniform velocity and turbulence profile. The jet-mainstream flow coupling is usually neglected because of the computational expense. This CFD study was performed to understand the effect of jet-mainstream flow coupling, and to assess the accuracy of jet boundary conditions that are commonly used in combustor internal calculations. A case representative of a plenum-fed quick-mix section of a Rich Burn/Quick Mix/Lean Burn combustor (i.e. a jet-mainstream mass-flow ratio of about 3 and a jet-mainstream momentum-flux ratio of about 30) was investigated. This case showed that the jet velocity entering the combustor was very non-uniform, with a low normal velocity at the leading edge of the orifice and a high normal velocity at the trailing edge of the orifice. Three different combustor-only cases were analyzed with uniform inlet jet profile. None of the cases matched the plenum-fed calculations. To assess liner thickness effects, a thin-walled case was also analyzed. The CFD analysis showed the thin-walled jets had more penetration than the thick-walled jets.

Nucleation of an oil phase in a nonionic microemulsion-containing chlorinated oil upon systematic temperature quench.

PubMed

Deen, G Roshan; Pedersen, Jan Skov

2010-06-17

A clear and stable nonionic model microemulsion consisting of pentaoxyethylene glycol dodecyl ether (C(12)E(5)), water, and 1-chlorotetradecane (CLTD) was prepared. This system was subjected to a systematic temperature quench (perturbation out of equilibrium) in steps of 1.0 degrees C from 20.4 to 15.3 degrees C in the unstable region of its phase diagram. The change in turbidity (for droplet volume fractions of 0.02 and 0.08) and hydrodynamic radius (R(h)) (for a droplet volume fraction of 0.02) of the system on its way to its new equilibrium was measured at each quench temperature. For small systematic temperature quenches just below the emulsification failure boundary (EFB) the turbidity decreases and remains constant indicating quick changes in the microstructures. Further lowering of temperature brings the system to the unstable region where the turbidity and light scattering increase sharply as function of time because of expulsion of excess oil from the microemulsion droplets. The newly formed oil-rich droplets grow in size as a function of time. These observations indicate the existence of a narrow but observable metastable region en route to the new equilibrium where both microemulsion droplets and larger oil-rich droplets coexist. The region in which microemulsion droplets are metastable is very narrow and is concentration-dependent. The presence of a metastable region is as for other similar systems attributed to the presence of a free energy barrier for the formation of the larger oil-rich droplets associated with curvature free energy of the surfactant film. The turbidity-time curves were converted to the radius-time curves using a model assuming monodisperse spherical droplets. The obtained results are in good agreement with the results for the hydrodynamic radius. The observed average radius from both type of measurements decreases in the metastable region. By performing calculation of the influence of eccentricity and size polydispersity on the observed radius, we have shown that the distribution of the microemulsion droplets becomes more homogeneous in the metastable region.

TRUNK LEAN DURING A SINGLE-LEG SQUAT IS ASSOCIATED WITH TRUNK LEAN DURING PITCHING.

PubMed

Plummer, Hillary A; Oliver, Gretchen D; Powers, Christopher M; Michener, Lori A

2018-02-01

Impaired trunk motion during pitching may be a risk factor for upper extremity injuries. Specifically, increased forces about the shoulder and elbow have been observed in pitchers with excessive contralateral trunk lean during pitching. Because of the difficulty in identifying abnormal trunk motions during a high-speed task such as pitching, a clinical screening test is needed to identify pitchers who have impaired trunk motion during pitching. The purpose of this study was to determine the relationship between the degree of lateral trunk lean during the single-leg squat and amount of trunk lean during pitching and if trunk lean during pitching can be predicted from lean during the single-leg squat. Controlled Laboratory Study; Cross-sectional. Seventy-three young baseball pitchers (11.4 ± 1.7 years; 156.3 ± 11.9 cm; 50.5 ± 8.8 kg) participated. An electromagnetic tracking system was used to obtain trunk kinematic data during a single-leg squat task (lead leg) and at maximum shoulder external rotation of a fastball pitch. Pearson correlation coefficients for trunk lean during the single-leg squat and pitching were calculated. A linear regression analysis was performed to determine if trunk lean during pitching can be predicted from lean during the single-leg squat. There was a positive correlation between trunk lean during the single-leg squat and trunk lean during pitching (r = 0.53; p<0.001). Lateral trunk lean during the single-leg squat predicted the amount of lateral trunk lean during pitching (R 2 = 0.28; p < 0.001). A moderate positive correlation was observed between trunk lean during an SLS and pitching. Trunk lean during the single-leg squat explained 28% of the variance in trunk lean during pitching. Diagnosis, level 3.

TRUNK LEAN DURING A SINGLE-LEG SQUAT IS ASSOCIATED WITH TRUNK LEAN DURING PITCHING

PubMed Central

Oliver, Gretchen D.; Powers, Christopher M.; Michener, Lori A.

2018-01-01

Background Impaired trunk motion during pitching may be a risk factor for upper extremity injuries. Specifically, increased forces about the shoulder and elbow have been observed in pitchers with excessive contralateral trunk lean during pitching. Because of the difficulty in identifying abnormal trunk motions during a high-speed task such as pitching, a clinical screening test is needed to identify pitchers who have impaired trunk motion during pitching. Hypothesis/Purpose The purpose of this study was to determine the relationship between the degree of lateral trunk lean during the single-leg squat and amount of trunk lean during pitching and if trunk lean during pitching can be predicted from lean during the single-leg squat. Study Design Controlled Laboratory Study; Cross-sectional. Methods Seventy-three young baseball pitchers (11.4 ± 1.7 years; 156.3 ± 11.9 cm; 50.5 ± 8.8 kg) participated. An electromagnetic tracking system was used to obtain trunk kinematic data during a single-leg squat task (lead leg) and at maximum shoulder external rotation of a fastball pitch. Pearson correlation coefficients for trunk lean during the single-leg squat and pitching were calculated. A linear regression analysis was performed to determine if trunk lean during pitching can be predicted from lean during the single-leg squat. Results There was a positive correlation between trunk lean during the single-leg squat and trunk lean during pitching (r = 0.53; p<0.001). Lateral trunk lean during the single-leg squat predicted the amount of lateral trunk lean during pitching (R2 = 0.28; p < 0.001). Conclusions A moderate positive correlation was observed between trunk lean during an SLS and pitching. Trunk lean during the single-leg squat explained 28% of the variance in trunk lean during pitching. Level of Evidence Diagnosis, level 3 PMID:29484242

A Web-Based Lean Simulation Game for Office Operations: Training the Other Side of a Lean Enterprise

ERIC Educational Resources Information Center

Kuriger, Glenn W.; Wan, Huang-da; Mirehei, S. Moussa; Tamma, Saumya; Chen, F. Frank

2010-01-01

This research proposes a Web-based version of a lean office simulation game (WeBLOG). The game is designed to be used to train lean concepts to office and administrative personnel. This group belongs to the frequently forgotten side of a lean enterprise. Over four phases, the game presents the following seven lean tools: one-piece flow,…

Lean leadership attributes: a systematic review of the literature.

PubMed

Aij, Kjeld Harald; Teunissen, Maurits

2017-10-09

Purpose Emphasis on quality and reducing costs has led many health-care organizations to reconfigure their management, process, and quality control infrastructures. Many are lean, a management philosophy with roots in manufacturing industries that emphasizes elimination of waste. Successful lean implementation requires systemic change and strong leadership. Despite the importance of leadership to successful lean implementation, few researchers have probed the question of ideal leadership attributes to achieve lean thinking in health care. The purpose of this paper is to provide insight into applicable attributes for lean leaders in health care. Design/methodology/approach The authors systematically reviewed the literature on principles of leadership and, using Dombrowski and Mielke's (2013) conceptual model of lean leadership, developed a parallel theoretical model for lean leadership in health care. Findings This work contributes to the development of a new framework for describing leadership attributes within lean management of health care. Originality/value The summary of attributes can provide a model for health-care leaders to apply lean in their organizations.

Cull sow knife-separable lean content evaluation at harvest and lean mass content prediction equation development.

PubMed

Abell, Caitlyn E; Stalder, Kenneth J; Hendricks, Haven B; Fitzgerald, Robert F

2012-07-01

The objectives of this study were to develop a prediction equation for carcass knife-separable lean within and across USDA cull sow market weight classes (MWC) and to determine carcass and individual primal cut knife separable lean content from cull sows. There were significant percent lean and fat differences in the primal cuts across USDA MWC. The two lighter USDA MWC had a greater percent carcass lean and lower percent fat compared to the two heavier MWC. In general, hot carcass weight explained the majority of carcass lean variation. Additionally, backfat was a significant variation source when predicting cull sow carcass lean. The findings support using a single lean prediction equation across MWC to assist processors when making cull sow purchasing decisions and determine the mix of animals from various USDA MWC that will meet their needs when making pork products with defined lean:fat content. Copyright © 2012 Elsevier Ltd. All rights reserved.

Prevalence and hemodynamic effects of leaning during CPR

PubMed Central

Niles, Dana E.; Sutton, Robert M.; Nadkarni, Vinay M.; Glatz, Andrew; Zuercher, Mathias; Maltese, Matthew R.; Eilevstjønn, Joar; Abella, Benjamin S.; Becker, Lance B.; Berg, Robert A.

2013-01-01

Background Cardiopulmonary resuscitation (CPR) guidelines recommend complete release between chest compressions (CC). Objective Evaluate the hemodynamic effects of leaning (incomplete chest wall release) during CPR and the prevalence of leaning during CPR. Results In piglet ventricular fibrillation cardiac arrests, 10% and 20% (1.8 kg and 3.6 kg, respectively), leaning during CPR increased right atrial pressures, decreased coronary perfusion pressures, and decreased cardiac index and left ventricular myocardial blood flow by nearly 50%. In contrast, residual leaning of a 260 g accelerometer/ force feedback device did not adversely affect cardiac index or myocardial blood flow. Among 108 adult in-hospital CPR events, leaning ≥2.5 kg was demonstrable in 91% of the events and 12% of the evaluated CC. For 12 children with in-hospital CPR, 28% of CC had residual leaning ≥2.5 kg and 89% had residual leaning ≥0.5 kg. Conclusions Leaning during CPR increases intrathoracic pressure, decreases coronary perfusion pressure, and decreases cardiac output and myocardial blood flow. Leaning is common during CPR. PMID:22208173

The PCOS Patients differ in Lipid Profile According to their Phenotypes.

PubMed

Spałkowska, Magdalena; Mrozińska, Sandra; Gałuszka-Bednarczyk, Anna; Gosztyła, Katarzyna; Przywara, Agnieszka; Guzik, Justyna; Janeczko, Marek; Milewicz, Tomasz; Wojas-Pelc, Anna

2018-01-31

Polycystic ovary syndrome (PCOS) affects 4-18% of women of reproductive age. The number of reports exploring the lipid profiles among PCOS patients and number of studied patients are limited. The aim of our study was to assess the lipid profile separately in lean and non-lean women with polycystic ovary syndrome divided according to hyperandrogenemia, defined as free androgen index (FAI)≥5. The second aim was to compare the lipid profiles among lean and non-lean PCOS patients with respect to hyperandrogenemia and regularity of menstruation cycles. We evaluated 232 patients from Department of Endocrinological Gynecology, Jagiellonian University Medical College in Krakow diagnosed with PCOS. The population consisted of 166 lean and 66 non-lean women. We observed higher levels of total cholesterol, high-density lipoprotein cholesterol (HDL-C) in lean patients with FAI<5 than in lean patients with FAI≥5. There were no differences in lipid profile between non-lean patients with FAI≥5 and non-lean patients with FAI<5. Among lean patients higher total cholesterol levels were observed in those with irregular menstruation cycles and FAI<5 than in patients with FAI≥5 and regular cycles. There were no differences in lipid profiles between four phenotypes among non-lean PCOS patients. The results of our study showed differences in lipid profile between lean PCOS patients according to their phenotype based on androgens' level. This effect was abandoned by fat tissue mass in non-lean ones. Further studies should be conducted to explore these associations. © Georg Thieme Verlag KG Stuttgart · New York.

Rapid mix concepts for low emission combustors in gas turbine engines

NASA Technical Reports Server (NTRS)

Talpallikar, Milind V.; Smith, Clifford E.; Lai, Ming-Chia

1990-01-01

NASA LeRC has identified the Rich burn/Quick mix/Lean burn (RQL) combustor as a potential gas turbine combustor concept to reduce NOx emissions in High Speed Civil Transport (HSCT) aircraft. To demonstrate reduced NOx levels, NASA LeRC soon will test a flametube version of an RQL combustor. The critical technology needed for the RQL combustor is a method of quickly mixing combustion air with rich burn gases. Two concepts were proposed to enhance jet mixing in a circular cross-section: the Asymmetric Jet Penetration (AJP) concept; and the Lobed Mixer (LM) concept. In Phase 1, two preliminary configurations of the AJP concept were compared with a conventional 12-jet radial-inflow slot design. The configurations were screened using an advanced 3-D Computational Fluid Dynamics (CFD) code named REFLEQS. Both non-reacting and reacting analyses were performed. For an objective comparison, the conventional design was optimized by parametric variation of the jet-to-mainstream momentum flux (J) ratio. The optimum J was then employed in the AJP simulations. Results showed that the three-jet AJP configuration was superior in overall mixedness compared to the conventional design. However, in regards to NOx emissions, the AJP configuration was inferior. The higher emission level for AJP was caused by a single hot spot located in the wake of the central jet as it entered the combustor. Ways of maintaining good mixedness while eliminating the hot spot were identified for Phase 2 study. Overall, Phase 1 showed the viability of using CFD analyses to evaluate quick-mix concepts. A high probability exists that advancing mixing concepts will reduce NOx emissions in RQL combustors, and should be explored in Phase 2, by parallel numerical and experimental work.

A case study on Measurement of Degree of Performance of an Industry by using Lean Score Technique

NASA Astrophysics Data System (ADS)

Srinivasa Rao, P.; Niraj, Malay

2016-09-01

Lean manufacturing concept is becoming a very important strategy for both academicians and practitioners in the recent times, and Japanese are using this practice for more than a decade. In this present scenario, this paper describes an innovative approach for lean performance evaluation by using fuzzy membership functions before and after implementing lean manufacturing techniques and formulating a model to establish the lean score through the lean attributes by eliminating major losses. It shows a systematic lean performance measurement by producing a final integrated unit less-score.

Development of framework for sustainable Lean implementation: an ISM approach

NASA Astrophysics Data System (ADS)

Jadhav, Jagdish Rajaram; Mantha, S. S.; Rane, Santosh B.

2014-07-01

The survival of any organization depends upon its competitive edge. Even though Lean is one of the most powerful quality improvement methodologies, nearly two-thirds of the Lean implementations results in failures and less than one-fifth of those implemented have sustained results. One of the most significant tasks of top management is to identify, understand and deploy the significant Lean practices like quality circle, Kanban, Just-in-time purchasing, etc. The term `bundle' is used to make groups of inter-related and internally consistent Lean practices. Eight significant Lean practice bundles have been identified based on literature reviewed and opinion of the experts. The order of execution of Lean practice bundles is very important. Lean practitioners must be able to understand the interrelationship between these practice bundles. The objective of this paper is to develop framework for sustainable Lean implementation using interpretive structural modelling approach.

Using Lean Process Improvement to Enhance Safety and Value in Orthopaedic Surgery: The Case of Spine Surgery.

PubMed

Sethi, Rajiv; Yanamadala, Vijay; Burton, Douglas C; Bess, Robert Shay

2017-11-01

Lean methodology was developed in the manufacturing industry to increase output and decrease costs. These labor organization methods have become the mainstay of major manufacturing companies worldwide. Lean methods involve continuous process improvement through the systematic elimination of waste, prevention of mistakes, and empowerment of workers to make changes. Because of the profit and productivity gains made in the manufacturing arena using lean methods, several healthcare organizations have adopted lean methodologies for patient care. Lean methods have now been implemented in many areas of health care. In orthopaedic surgery, lean methods have been applied to reduce complication rates and create a culture of continuous improvement. A step-by-step guide based on our experience can help surgeons use lean methods in practice. Surgeons and hospital centers well versed in lean methodology will be poised to reduce complications, improve patient outcomes, and optimize cost/benefit ratios for patient care.

Application of lean thinking to health care: issues and observations

PubMed Central

Joosten, Tom; Bongers, Inge; Janssen, Richard

2009-01-01

Background Incidents and quality problems are a prime cause why health care leaders are calling to redesign health care delivery. One of the concepts used is lean thinking. Yet, lean often leads to resistance. Also, there is a lack of high quality evidence supporting lean premises. In this paper, we present an overview of lean thinking and its application to health care. Development, theory and application of lean thinking to health care Lean thinking evolved from a tool designed to improve operational shop-floor performance at an automotive manufacturer to a management approach with both operational and sociotechnical aspects. Sociotechnical dynamics have until recently not received much attention. At the same time a balanced approach might lead to a situation where operational and sociotechnial improvements are mutually reinforcing. Application to health care has been limited and focussed mainly on operational aspects using original lean tools. A more integrative approach would be to pay more attention to sociotechnical dynamics of lean implementation efforts. Also, the need to use the original lean tools may be limited, because health care may have different instruments and tools already in use that are in line with lean thinking principles. Discussion We believe lean thinking has the potential to improve health care delivery. At the same time, there are methodological and practical considerations that need to be taken into account. Otherwise, lean implementation will be superficial and fail, adding to existing resistance and making it more difficult to improve health care in the long term. PMID:19696048

Lost in translation: a case-study of the travel of lean thinking in a hospital.

PubMed

Andersen, Hege; Røvik, Kjell Arne

2015-09-21

Lean thinking as a quality improvement approach is introduced in hospitals worldwide, although evidence for its impact is scarce. Lean initiatives are social, complex and context-dependent. This calls for a shift from cause-effect to conditional attributions to understand how lean works. In this study, we bring attention to the transformative power of local translation, which creates different versions of lean in different contexts, and thereby affect the evidence for lean as well as the success of lean initiatives within and among hospitals. We explored the travel of lean within a hospital in Norway by identifying local actors' perceptions of lean through their images of enablers for successful interventions. These attributions describe the characteristics of lean in use, i.e. the prevailing version of lean. Local actors' perceptions of enablers for lean interventions were collected through focus group interviews with three groups of stakeholders: managers, internal consultants and staff. A questionnaire was used to reveal the enablers relative importance. The enablers known from the literature were retrieved at the case hospital. The only exception was that external expert change agents were not believed to promote lean. In addition, the stakeholders added a number of new and supplementary enablers. Two-thirds of the most important enablers for success were novel, local ones. Among these were a problem, not method focus, a bottom-up approach, the need of internal consultants, credibility, realism and patience. The local actors told different stories about local enablers and had different images of lean depending on their hierarchical level. By comparing and analyzing the findings from the literature review, the focus groups and the survey, we deduced that the travel of lean within the hospital was affected by three principles of translation: the practical, the pragmatic, and the sceptical. Further, three logics of translation were in play: translation as a funnel, a conscious sell-in, and a wash-out. This resulted in various local versions of lean. We conclude that lean, introduced by the management, communicated by the internal consultants, and used by the staff, is transformed more than once within the hospital. Translation is part of the explanation for the lack of evidence for lean, and translation can be decisive for outcomes.

A Systematic Approach to Applying Lean Techniques to Optimize an Office Process at the Y-12 National Security Complex

DOE Office of Scientific and Technical Information (OSTI.GOV)

Credille, Jennifer; Owens, Elizabeth

This capstone offers the introduction of Lean concepts to an office activity to demonstrate the versatility of Lean. Traditionally Lean has been associated with process improvements as applied to an industrial atmosphere. However, this paper will demonstrate that implementing Lean concepts within an office activity can result in significant process improvements. Lean first emerged with the conception of the Toyota Production System. This innovative concept was designed to improve productivity in the automotive industry by eliminating waste and variation. Lean has also been applied to office environments, however the limited literature reveals most Lean techniques within an office are restrictedmore » to one or two techniques. Our capstone confronts these restrictions by introducing a systematic approach that utilizes multiple Lean concepts. The approach incorporates: system analysis, system reliability, system requirements, and system feasibility. The methodical Lean outline provides tools for a successful outcome, which ensures the process is thoroughly dissected and can be achieved for any process in any work environment.« less

Grain Refinement and Texture Mitigation in Low Boron Containing TiAl-Alloys

NASA Astrophysics Data System (ADS)

Hecht, Ulrike; Witusiewicz, Victor T.

2017-12-01

Controlling the grain size and texture of lamellar TiAl-alloys is essential for well-balanced creep and fatigue properties. Excellent refinement and texture mitigation are achieved in aluminum lean alloys by low boron additions of 0.2 at.%. This amount is sufficient to promote in situ formation of ultrafine borides during the last stages of body centered cubic (BCC) solidification. The borides subsequently serve as nucleation sites for hexagonal close packed (HCP) during the BCC-HCP phase transformation. Bridgman solidification experiments with alloy Ti-43Al-8Nb-0.2C-0.2B were performed under a different growth velocity, i.e., cooling rate, to evaluate the HCP grain size distribution and texture. For slow-to-moderate cooling rates, about 65% of HCP grains are randomly oriented, despite the pronounced texture of the parent BCC phase resulting from directional solidification. For high cooling rates, obtained by quenching, texture mitigation is less pronounced. Only 28% of the HCP grains are randomly oriented, the majority being crystallographic variants of the Burgers orientation relationship.

Lean thinking in emergency departments: concepts and tools for quality improvement.

PubMed

Bruno, Frances

2017-10-12

The lean approach is a viable framework for reducing costs and enhancing the quality of patient care in emergency departments (EDs). Reports on lean-inspired quality improvement initiatives are rapidly growing but there is little emphasis on the philosophy behind the processes, which is the essential ingredient in sustaining transformation. This article describes lean philosophy, also referred to as lean, lean thinking and lean healthcare, and its main concepts, to enrich the knowledge and vocabulary of nurses involved or interested in quality improvement in EDs. The article includes examples of lean strategies to illustrate their practical application in EDs. ©2012 RCN Publishing Company Ltd. All rights reserved. Not to be copied, transmitted or recorded in any way, in whole or part, without prior permission of the publishers.

The prevalence of chest compression leaning during in-hospital cardiopulmonary resuscitation

PubMed Central

Fried, David A.; Leary, Marion; Smith, Douglas A.; Sutton, Robert M.; Niles, Dana; Herzberg, Daniel L.; Becker, Lance B.; Abella, Benjamin S.

2011-01-01

Objective Successful resuscitation from cardiac arrest requires the delivery of high-quality chest compressions, encompassing parameters such as adequate rate, depth, and full recoil between compressions. The lack of compression recoil (“leaning” or “incomplete recoil”) has been shown to adversely affect hemodynamics in experimental arrest models, but the prevalence of leaning during actual resuscitation is poorly understood. We hypothesized that leaning varies across resuscitation events, possibly due to rescuer and/or patient characteristics and may worsen over time from rescuer fatigue during continuous chest compressions. Methods This was an observational clinical cohort study at one academic medical center. Data were collected from adult in-hospital and Emergency Department arrest events using monitor/defibrillators that record chest compression characteristics and provide real-time feedback. Results We analyzed 112,569 chest compressions from 108 arrest episodes from 5/2007 to 2/2009. Leaning was present in 98/108 (91%) cases; 12% of all compressions exhibited leaning. Leaning varied widely across cases: 41/108 (38%) of arrest episodes exhibited <5% leaning yet 20/108 (19%) demonstrated >20% compression leaning. When evaluating blocks of continuous compressions (>120 sec), only 4/33 (12%) had an increase in leaning over time and 29/33 (88%) showed a decrease (p<0.001). Conclusions Chest compression leaning was common during resuscitation care and exhibited a wide distribution, with most leaning within a subset of resuscitations. Leaning decreased over time during continuous chest compression blocks, suggesting that either leaning may not be a function of rescuer fatiguing, or that it may have been mitigated by automated feedback provided during resuscitation episodes. PMID:21482010

Risk Factors for the Loss of Lean Body Mass After Gastrectomy for Gastric Cancer.

PubMed

Aoyama, Toru; Sato, Tsutomu; Segami, Kenki; Maezawa, Yukio; Kano, Kazuki; Kawabe, Taiichi; Fujikawa, Hirohito; Hayashi, Tsutomu; Yamada, Takanobu; Tsuchida, Kazuhito; Yukawa, Norio; Oshima, Takashi; Rino, Yasushi; Masuda, Munetaka; Ogata, Takashi; Cho, Haruhiko; Yoshikawa, Takaki

2016-06-01

Lean body mass loss after surgery, which decreases the compliance of adjuvant chemotherapy, is frequently observed in gastric cancer patients who undergo gastrectomy for gastric cancer. However, the risk factors for loss of lean body mass remain unclear. The current study retrospectively examined the patients who underwent curative gastrectomy for gastric cancer between June 2010 and March 2014 at Kanagawa Cancer Center. All the patients received perioperative care for enhanced recovery after surgery. The percentage of lean body mass loss was calculated by the percentile of lean body mass 1 month after surgery to preoperative lean body mass. Severe lean body mass loss was defined as a lean body mass loss greater than 5 %. Risk factors for severe lean body mass loss were determined by both uni- and multivariate logistic regression analyses. This study examined 485 patients. The median loss of lean body mass was 4.7 %. A lean body mass loss of 5 % or more occurred for 225 patients (46.4 %). Both uni- and multivariate logistic analyses demonstrated that the significant independent risk factors for severe lean body mass loss were surgical complications with infection or fasting (odds ratio [OR] 3.576; p = 0.001), total gastrectomy (OR 2.522; p = 0.0001), and gender (OR 1.928; p = 0.001). Nutritional intervention or control of surgical invasion should be tested in future clinical trials for gastric cancer patients with these risk factors to maintain lean body mass after gastrectomy.

Visualization of nucleic acids with synthetic exciton-controlled fluorescent oligonucleotide probes.

PubMed

Wang, Dan Ohtan; Okamoto, Akimitsu

2015-01-01

Engineered probes to adapt new photochemical properties upon recognition of target nucleic acids offer powerful tools to DNA and RNA visualization technologies. Herein, we describe a rapid and effective visualization method of nucleic acids in both fixed and living cells with hybridization-sensitive fluorescent oligonucleotide probes. These probes are efficiently quenched in an aqueous environment due to the homodimeric, excitonic interactions between fluorophores but become highly fluorescent upon hybridization to DNA or RNA with complementary sequences. The fast hybridization kinetics and quick fluorescence activation of the new probes allow applications to simplify the conventional fluorescent in situ hybridization protocols and reduce the amount of time to process the samples. Furthermore, hybridization-sensitive fluorescence emission of the probes allows monitoring dynamic behaviors of RNA in living cells.

Effect of Annealing on Exciton Diffusion in a High Performance Small Molecule Organic Photovoltaic Material.

PubMed

Long, Yun; Hedley, Gordon J; Ruseckas, Arvydas; Chowdhury, Mithun; Roland, Thomas; Serrano, Luis A; Cooke, Graeme; Samuel, Ifor D W

2017-05-03

Singlet exciton diffusion was studied in the efficient organic photovoltaic electron donor material DTS(FBTTh 2 ) 2 . Three complementary time-resolved fluorescence measurements were performed: quenching in planar heterojunctions with an electron acceptor, exciton-exciton annihilation, and fluorescence depolarization. The average exciton diffusivity increases upon annealing from 1.6 × 10 -3 to 3.6 × 10 -3 cm 2 s -1 , resulting in an enhancement of the mean two-dimensional exciton diffusion length (L D = (4Dτ) 1/2 ) from 15 to 27 nm. About 30% of the excitons get trapped very quickly in as-cast films. The high exciton diffusion coefficient of the material leads to it being able to harvest excitons efficiently from large donor domains in bulk heterojunctions.

Effect of Annealing on Exciton Diffusion in a High Performance Small Molecule Organic Photovoltaic Material

PubMed Central

2017-01-01

Singlet exciton diffusion was studied in the efficient organic photovoltaic electron donor material DTS(FBTTh2)2. Three complementary time-resolved fluorescence measurements were performed: quenching in planar heterojunctions with an electron acceptor, exciton–exciton annihilation, and fluorescence depolarization. The average exciton diffusivity increases upon annealing from 1.6 × 10–3 to 3.6 × 10–3 cm2 s–1, resulting in an enhancement of the mean two-dimensional exciton diffusion length (LD = (4Dτ)1/2) from 15 to 27 nm. About 30% of the excitons get trapped very quickly in as-cast films. The high exciton diffusion coefficient of the material leads to it being able to harvest excitons efficiently from large donor domains in bulk heterojunctions. PMID:28358189

Lean leadership: an ethnographic study.

PubMed

Aij, Kjeld Harald; Visse, Merel; Widdershoven, Guy A M

2015-01-01

The purpose of this study is to provide a critical analysis of contemporary Lean leadership in the context of a healthcare practice. The Lean leadership model supports professionals with a leading role in implementing Lean. This article presents a case study focusing specifically on leadership behaviours and issues that were experienced, observed and reported in a Dutch university medical centre. This ethnographic case study provides auto-ethnographic accounts based on experiences, participant observation, interviews and document analysis. Characteristics of Lean leadership were identified to establish an understanding of how to achieve successful Lean transformation. This study emphasizes the importance for Lean leaders to go to the gemba, to see the situation for one's own self, empower health-care employees and be modest. All of these are critical attributes in defining the Lean leadership mindset. In this case study, Lean leadership is specifically related to healthcare, but certain common leadership characteristics are relevant across all fields. This article shows the value of an auto-ethnographic view on management learning for the analysis of Lean leadership. The knowledge acquired through this research is based on the first author's experiences in fulfilling his role as a health-care leader. This may help the reader examining his/her own role and reflecting on what matters most in the field of Lean leadership.

EPA Lean Government Initiative: How to Replicate Lean Successes

EPA Pesticide Factsheets

This Lean Replication Primer describes how EPA Offices and Regions can identify and adapt successful practices from previous Lean projects to “replicate” their successes and generate further improvements.

A Methodology for the Assessment of Experiential Learning Lean: The Lean Experience Factory Study

ERIC Educational Resources Information Center

De Zan, Giovanni; De Toni, Alberto Felice; Fornasier, Andrea; Battistella, Cinzia

2015-01-01

Purpose: The purpose of this paper is to present a methodology to assess the experiential learning processes of learning lean in an innovative learning environment: the lean model factories. Design/methodology/approach: A literature review on learning and lean management literatures was carried out to design the methodology. Then, a case study…

Lean and Information Technology Toolkit

EPA Pesticide Factsheets

The Lean and Information Technology Toolkit is a how-to guide which provides resources to environmental agencies to help them use Lean Startup, Lean process improvement, and Agile tools to streamline and automate processes.

System-wide lean implementation in health care: A multiple case study.

PubMed

Centauri, Federica; Mazzocato, Pamela; Villa, Stefano; Marsilio, Marta

2018-05-01

Background Lean practices have been widely used by health care organizations to meet efficiency, performance and quality improvement needs. The lean health care literature shows that the effective implementation of lean requires a holistic system-wide approach. However, there is still limited evidence on what drives effective system-wide lean implementation in health care. The existing literature suggests that a deeper understanding of how lean interventions interact with the organizational context is necessary to identify the critical variables to successfully sustain system-wide lean strategies. Purpose and methodology: A multiple case study of three Italian hospitals is conducted with the aim to explore the organizational conditions that are relevant for an effective system-wide lean implementation. A conceptual framework, built on socio-technical system schemas, is used to guide data collection and analysis. The analysis points out the importance to support lean implementation with an integrated and coordinated strategy involving the social, technical, and external components of the overall hospital system.

Packages of participation: Swedish employees' experience of Lean depends on how they are involved.

PubMed

Brännmark, Mikael; Holden, Richard J

2013-01-01

Lean Production is a dominant approach in Swedish and global manufacturing and service industries. Studies of Lean's employee effects are few and contradictory. Employee effects from Lean are likely not uniform. This paper investigates the effect of employees' participation on their experiences of Lean. This study investigated how different packages of employee participation in Lean affected manufacturing workers' experiences of Lean. During 2008-2011, qualitative and quantitative data were collected from Swedish manufacturing companies participating in the national Swedish Lean Production program Produktionslyftet. Data from 129 surveys (28 companies), 39 semi-structured interviews, and 30 reports were analyzed. In the main analysis, comparisons were made of the survey-reported Lean experiences of employees in three groups: temporary group employees (N = 36), who participated in Lean mostly through intermittent projects; continuous group employees (N = 69), who participated through standing improvement groups; and combined group employees (N = 24), who participated in both ways. Continuous group employees had the most positive experience of Lean, followed by the combined group. Temporary group employees had the least positive experiences, being less likely than their counterparts to report that Lean improved teamwork, occupational safety, and change-related learning, decision making, and authority. These findings support the importance of continuous, structured opportunities for participation but raise the possibility that more participation may result in greater workload and role overload, mitigating some benefits of employee involvement. Consequently, companies should consider involving employees in change efforts but should attend to the specific design of participation activities.

Application of kaizen methodology to foster departmental engagement in quality improvement.

PubMed

Knechtges, Paul; Decker, Michael Christopher

2014-12-01

The Toyota Production System, also known as Lean, is a structured approach to continuous quality improvement that has been developed over the past 50 years to transform the automotive manufacturing process. In recent years, these techniques have been successfully applied to quality and safety improvement in the medical field. One of these techniques is kaizen, which is the Japanese word for "good change." The central tenant of kaizen is the quick analysis of the small, manageable components of a problem and the rapid implementation of a solution with ongoing, real-time reassessment. Kaizen adds an additional "human element" that all stakeholders, not just management, must be involved in such change. Because of the small size of the changes involved in a kaizen event and the inherent focus on human factors and change management, a kaizen event can serve as good introduction to continuous quality improvement for a radiology department. Copyright © 2014. Published by Elsevier Inc.

Self-directed work teams in marketing organizations.

PubMed

Gilbertson, T F

1999-01-01

As marketing organizations move toward the 21st century they are becoming concerned with the development of self-directed work teams. Marketing organizations that have informed, motivated, skilled, trained, and committed employees will out perform organizations which operate in the traditional manner. Many self-directed work teams have grown out of the quality circles. The goal of these teams is to increase employee involvement in decisions of the organization to the greatest extent that employees' knowledge and training allow. In fact, today's marketing organizations need to be able to respond quickly to change driven by internal and external customers. The winning organizations will be able to produce more product with better quality in less time by staying lean, flexible, and implementing self-directed work teams. Marketing organizations that can commit to self-directed work teams will benefit by having customer and employee satisfaction, money saved, and excessive bureaucracy eliminated.

Development of a preprototype sabatier CO2 reduction subsystem

NASA Technical Reports Server (NTRS)

Kleiner, G. N.; Birbara, P.

1980-01-01

A preoprototype Sabatier CO2 Reduction Subsystem was successfully designed, fabricated and tested. The lightweight, quick starting reactor utilizes a highly active and physically durable methanation catalyst composed of ruthenium on alumina. The use of this improved catalyst permits a single straight through plug flow design with an average lean component H2/CO2 conversion efficiency of over 99% over a range of H2/CO2 molar ratios of 1.8 to 5 while operating with flows equivalent to a crew size of one person steadystate to 3 persons cyclical (equivalent to 5 persons steady state). The reactor requires no heater operation after start-up even during simulated 55 minute lightside/39 minute darkside orbital operation over the above range of molar ratios and crew loadings. The subsystem's operation and performance is controlled by a microprocessor and displayed on a nineteen inch multi-colored cathode ray tube.

Case study on industrial hazmat response teams.

PubMed

Stephens, Shelly J

2009-11-01

In 1991, Amway formed an industrial hazardous materials (hazmat) team in order to respond quickly and efficiently to potential chemical spills. The company's goals were, and still are today, to protect employees, the environment and the local community, and to reduce the amount of resulting downtime. In 1991, the hazmat team was very well funded, enabling it to become a discrete department with its own management staff and nearly 100 hazmat volunteers. Due to changes in the business climate, Amway reorganised in 2000/01, and the hazmat team became part of a company that incorporated contract work into its scope. When this reorganisation occurred, the hazmat team was thoroughly re-evaluated. Its response function was maintained, but was systematically reinvented in the most lean way practicable while still meeting corporate goals. This case study represents Amway's hazmat team's journey through the evaluation process and subsequent reorganisation.

Development of a preprototype Sabatier CO2 reduction subsystem

NASA Technical Reports Server (NTRS)

Kleiner, G. N.; Birbara, P.

1981-01-01

A lightweight, quick starting reactor utilizes a highly active and physically durable methanation catalyst composed of ruthenium on alumina. The use of this improved catalyst permits a single straight through plug flow design with an average lean component H2/CO2 conversion efficiency of over 99% over a range of H2/CO2 molar ratios of 1.8 to 5 while operating with flows equivalent to a crew size of one person steadystate to 3 persons cyclical. The reactor requires no heater operation after start-up even during simulated 55 minute lightside/39 minute darkside orbital operation over the above range of molar ratios and crew loadings. Subsystem performance was proven by parametric testing and endurance testing over a wide range of crew sizes and metabolic loadings. The subsystem's operation and performance is controlled by a microprocessor and displayed on a nineteen inch multi-colored cathode ray tube.

Lean Management Systems in Radiology: Elements for Success.

PubMed

Schultz, Stacy R; Ruter, Royce L; Tibor, Laura C

2016-01-01

This article is a review of the literature on Lean and Lean Management Systems and how they have been implemented in healthcare organizations and particularly in radiology departments. The review focuses on the elements required for a successful implementation of Lean by applying the principles of a Lean Management System instead of a Lean tools-only approach. This review shares the successes and failures from healthcare organizations' efforts to improve the quality and safety of the services they provide. There are a limited number of healthcare organizations in the literature who have shared their experiences and additional research is necessary to determine whether a Lean Management System is a viable alternative to the current management structure in healthcare.

Alcohol produces distinct hepatic lipidome and eicosanoid signature in lean and obese[S

PubMed Central

Puri, Puneet; Xu, Jun; Vihervaara, Terhi; Katainen, Riikka; Ekroos, Kim; Daita, Kalyani; Min, Hae-Ki; Joyce, Andrew; Mirshahi, Faridoddin; Tsukamoto, Hidekazu; Sanyal, Arun J.

2016-01-01

Alcohol- and obesity-related liver diseases often coexist. The hepatic lipidomics due to alcohol and obesity interaction is unknown. We characterized the hepatic lipidome due to 1) alcohol consumption in lean and obese mice and 2) obesity and alcohol interactions. In the French-Tsukamoto mouse model, intragastric alcohol or isocaloric dextrose were fed with either chow (lean) or high-fat, high-cholesterol diet (obese). Four groups (lean, lean alcohol, obese, and obese alcohol) were studied. MS was performed for hepatic lipidomics, and data were analyzed. Alcohol significantly increased hepatic cholesteryl esters and diacyl­glycerol in lean and obese but was more pronounced in obese. Alcohol produced contrasting changes in hepatic phospholipids with significant enrichment in lean mice versus significant decrease in obese mice, except phosphatidylglycerol, which was increased in both lean and obese alcohol groups. Most lysophospholipids were increased in lean alcohol and obese mice without alcohol use only. Prostaglandin E2; 5-, 8-, and 11-hydroxyeicosatetraenoic acids; and 9- and 13-hydroxyoctadecadienoic acids were considerably increased in obese mice with alcohol use. Alcohol consumption produced distinct changes in lean and obese with profound effects of obesity and alcohol interaction on proinflammatory and oxidative stress-related eicosanoids. PMID:27020313

Improving first case start times using Lean in an academic medical center.

PubMed

Deldar, Romina; Soleimani, Tahereh; Harmon, Carol; Stevens, Larry H; Sood, Rajiv; Tholpady, Sunil S; Chu, Michael W

2017-06-01

Lean is a process improvement strategy that can improve efficiency of the perioperative process. The purpose of this study was to identify etiologies of late surgery start times, implement Lean interventions, and analyze their effects. A retrospective review of all first-start surgery cases was performed. Lean was implemented in May 2015, and cases 7 months before and after implementation were analyzed. A total of 4,492 first-start cases were included; 2,181 were pre-Lean and 2,311 were post-Lean. The post-Lean group had significantly higher on-time starts than the pre-Lean group (69.0% vs 57.0%, P < .01). The most common delay etiology was surgeon-related for both groups. Delayed post-Lean cases were significantly less likely to be due to preoperative assessment (14.9% vs 9.9%, P < .01) and more likely due to patient-related (16.5% vs 22.3%, P < .01) or chaplain (1.8% vs 4.0%, P < .01) factors. Delayed starts occurred more often on snowy and cold days, and less often on didactic days (P < .01). Modifying preoperative tasks using Lean methods can improve operating room efficiency and increase on-time starts. Copyright © 2016 Elsevier Inc. All rights reserved.

Sire carcass breeding values affect body composition in lambs - 1. Effects on lean weight and its distribution within the carcass as measured by computed tomography.

PubMed

Anderson, F; Williams, A; Pannier, L; Pethick, D W; Gardner, G E

2015-10-01

Data are obtained from computed tomography scanning of 1665 lambs at locations around Australia. Lambs were progeny of Terminal, Maternal and Merino sires with known Australian Sheep Breeding Values for post weaning c-site eye muscle depth (mm; PEMD) and fat depth (mm; PFAT), and post weaning weight (kg; PWWT). Across the 7.8 unit range of sire PEMD, carcass lean weight increased by 7.7%. This lean was distributed to the saddle section (mid-section) where lean became 3.8% heavier, with fore section lean becoming 3.5% lighter. Reducing sire PFAT across its 5.1 unit range increased carcass lean weight by 9.5%, and distributed lean to the saddle section which was 3.7% heavier. Increasing sire PWWT increased lean at some sites in some years, and on average increased saddle lean by 4% across the 24.7 unit PWWT range. Changes in lean weight and distribution due to selection for carcass breeding values will increase carcass value, particularly through increased weight of high value loin cuts. Copyright © 2015. Published by Elsevier Ltd.

Prevalence of Suspected Nonalcoholic Fatty Liver Disease In Lean Adolescents In The United States.

PubMed

Selvakumar, Praveen Kumar Conjeevaram; Kabbany, Mohammad Nasser; Lopez, Rocio; Rayas, Maria S; Lynch, Jane L; Alkhouri, Naim

2018-03-21

Nonalcoholic fatty liver disease (NAFLD) can develop in lean subjects referred to as lean NAFLD. We aim to evaluate the prevalence and risk factors of NAFLD in lean adolescents in the United States (US). Cross sectional data from 1482 lean subjects (body mass index < 85 percentile) aged between 12 and 18 years, who were enrolled in the National Health and Examination Survey during the 2005-2014 cycles were included. We defined suspected NAFLD as alanine aminotransferase > 25.8 U/L for boys and > 22.1 U/L for girls; hypertriglyceridemia as triglycerides ≥ 150 mg/dL; low HDL as HDL < 40 mg/dL and insulin resistance (IR) as homeostatic model assessment of IR ≥ 3. The mean weighted prevalence of suspected NAFLD among lean adolescents during 2005-2014 cycles was 8% (95% CI: 6.2, 9.9). Lean subjects with suspected NAFLD were significantly older compared to lean non-NAFLD subjects (15.5 vs. 15 years, p-value < 0.05). Low HDL (15.5% vs. 6.8%; p-value 0.016) and hypertriglyceridemia (10% vs. 3.9%; p-value 0.028) were also found to be more common among lean NAFLD subjects compared to their non-NAFLD counterparts. Presence of IR increased the risk of having suspected NAFLD by 4-fold among lean adolescents. Non-Hispanic black lean adolescents were less likely to have suspected NAFLD compared to non-Hispanic white lean adolescents. The estimated prevalence of suspected NAFLD among lean adolescents in the US was found to be 8% with evidence of metabolic derangements such as low HDL, hypertriglyceridemia and IR.

Gene expression microarray profiles of cumulus cells in lean and overweight-obese polycystic ovary syndrome patients.

PubMed

Kenigsberg, Shlomit; Bentov, Yaakov; Chalifa-Caspi, Vered; Potashnik, Gad; Ofir, Rivka; Birk, Ohad S

2009-02-01

The aim of this work was to study gene expression patterns of cultured cumulus cells from lean and overweight-obese polycystic ovary syndrome (PCOS) patients using genome-wide oligonucleotide microarray. The study included 25 patients undergoing in vitro fertilization and intra-cytoplasmic sperm injection: 12 diagnosed with PCOS and 13 matching controls. Each of the groups was subdivided into lean (body mass index (BMI) < 24) and overweight (BMI > 27) subgroups. The following comparisons of gene expression data were made: lean PCOS versus lean controls, lean PCOS versus overweight PCOS, all PCOS versus all controls, overweight PCOS versus overweight controls, overweight controls versus lean controls and all overweight versus all lean. The largest number of differentially expressed genes (DEGs), with fold change (FC) |FC| >or= 1.5 and P-value < 0.01, was found in the lean PCOS versus lean controls comparison (487) with most of these genes being down-regulated in PCOS. The second largest group of DEGs originated from the comparison of lean PCOS versus overweight PCOS (305). The other comparisons resulted in a much smaller number of DEGs (174, 109, 125 and 12, respectively). In the comparison of lean PCOS with lean controls, most DEGs were transcription factors and components of the extracellular matrix and two pathways, Wnt/beta-catenin and mitogen-activated protein kinase. When comparing overweight PCOS with overweight controls, most DEGs were of pathways related to insulin signaling, metabolism and energy production. The finding of unique gene expression patterns in cumulus cells from the two PCOS subtypes is in agreement with other studies that have found the two to be separate entities with potentially different pathophysiologies.

Effects of organizational context on Lean implementation in five hospital systems.

PubMed

Harrison, Michael I; Paez, Kathryn; Carman, Kristin L; Stephens, Jennifer; Smeeding, Lauren; Devers, Kelly J; Garfinkel, Steven

2016-01-01

Despite broad agreement among researchers about the value of examining how context shapes implementation of improvement programs and projects, limited attention has been paid to contextual effects on implementation of Lean. To help reduce gaps in knowledge of effects of intraorganizational context, we researched Lean implementation initiatives in five organizations and examined 12 of their Lean rapid improvement projects. All projects aimed at improving clinical care delivery. On the basis of the literature on Lean, innovation, and quality improvement, we developed a framework of factors likely to affect Lean implementation and outcomes. Drawing on the framework, we conducted semistructured interviews and applied qualitative codes to the transcribed interviews. Available documents, data, and observations supplemented the interviews. We constructed case studies of Lean implementation in each organization, compared implementation across organizations, and compared the 12 projects. Intraorganizational characteristics affecting organization-wide Lean initiatives and often also shaping project outcomes included CEO commitment to Lean and active support for it, prior organizational capacity for quality improvement-based performance improvement, alignment of the Lean initiative with the organizational mission, dedication of resources and experts to Lean, staff training before and during projects, establishment of measurable and relevant project targets, planning of project sequences that enhance staff capabilities and commitment without overburdening them, and ensuring communication between project members and other affected staff. Dependence of projects on inputs of new information technology was a barrier to project success. Incremental implementation of Lean produced reported improvements in operational efficiency and occasionally in care quality. However, even under the relatively favorable circumstances prevailing in our study sites, incremental implementation did not readily change organizational culture. This study should alert researchers, managers, and teachers of management to ways that contexts shape Lean implementation and may affect other types of process redesign and quality improvement.

Application of lean manufacturing techniques in the Emergency Department.

PubMed

Dickson, Eric W; Singh, Sabi; Cheung, Dickson S; Wyatt, Christopher C; Nugent, Andrew S

2009-08-01

"Lean" is a set of principles and techniques that drive organizations to continually add value to the product they deliver by enhancing process steps that are necessary, relevant, and valuable while eliminating those that fail to add value. Lean has been used in manufacturing for decades and has been associated with enhanced product quality and overall corporate success. To evaluate whether the adoption of Lean principles by an Emergency Department (ED) improves the value of emergency care delivered. Beginning in December 2005, we implemented a variety of Lean techniques in an effort to enhance patient and staff satisfaction. The implementation followed a six-step process of Lean education, ED observation, patient flow analysis, process redesign, new process testing, and full implementation. Process redesign focused on generating improvement ideas from frontline workers across all departmental units. Value-based and operational outcome measures, including patient satisfaction, expense per patient, ED length of stay (LOS), and patient volume were compared for calendar year 2005 (pre-Lean) and periodically after 2006 (post-Lean). Patient visits increased by 9.23% in 2006. Despite this increase, LOS decreased slightly and patient satisfaction increased significantly without raising the inflation adjusted cost per patient. Lean improved the value of the care we delivered to our patients. Generating and instituting ideas from our frontline providers have been the key to the success of our Lean program. Although Lean represents a fundamental change in the way we think of delivering care, the specific process changes we employed tended to be simple, small procedure modifications specific to our unique people, process, and place. We, therefore, believe that institutions or departments aspiring to adopt Lean should focus on the core principles of Lean rather than on emulating specific process changes made at other institutions.

Non-alcoholic Fatty Liver Disease in Lean Subjects: Characteristics and Implications.

PubMed

Kumar, Ramesh; Mohan, Shantam

2017-09-28

Non-alcoholic fatty liver disease (NAFLD) is commonly diagnosed in obese subjects; however, it is not rare among lean individuals. Given the absence of traditional risk factors, it tends to remain under-recognised. The metabolic profiles of lean NAFLD patients are frequently comparable to those of obese NAFLD patients. Though results from several studies have been mixed, it has been generally revealed that lean subjects with NAFLD have minor insulin resistance compared to that in obese NAFLD. Several genetic variants are associated with NAFLD without insulin resistance. Some data suggest that the prevalence of steatohepatitis and advanced fibrosis do not differ significantly between lean and obese NAFLD; however, the former tend to have less severe disease at presentation. The underlying pathophysiology of lean NAFLD may be quite different. Genetic predispositions, fructose- and cholesterol-rich diet, visceral adiposity and dyslipidaemia have potential roles in the pathogenic underpinnings. Lean NAFLD may pose a risk for metabolic disturbances, cardiovascular morbidity or overall mortality. Secondary causes of hepatic steatosis are also needed to be ruled out in lean subjects with NAFLD. The effectiveness of various treatment modalities, such as exercise and pharmacotherapy, on lean NAFLD is not known. Weight loss is expected to help lean NAFLD patients who have visceral obesity. Further investigation is needed for many aspects of lean NAFLD, including mechanistic pathogenesis, risk assessment, natural history and therapeutic approach.

Non-alcoholic Fatty Liver Disease in Lean Subjects: Characteristics and Implications

PubMed Central

Kumar, Ramesh; Mohan, Shantam

2017-01-01

Abstract Non-alcoholic fatty liver disease (NAFLD) is commonly diagnosed in obese subjects; however, it is not rare among lean individuals. Given the absence of traditional risk factors, it tends to remain under-recognised. The metabolic profiles of lean NAFLD patients are frequently comparable to those of obese NAFLD patients. Though results from several studies have been mixed, it has been generally revealed that lean subjects with NAFLD have minor insulin resistance compared to that in obese NAFLD. Several genetic variants are associated with NAFLD without insulin resistance. Some data suggest that the prevalence of steatohepatitis and advanced fibrosis do not differ significantly between lean and obese NAFLD; however, the former tend to have less severe disease at presentation. The underlying pathophysiology of lean NAFLD may be quite different. Genetic predispositions, fructose- and cholesterol-rich diet, visceral adiposity and dyslipidaemia have potential roles in the pathogenic underpinnings. Lean NAFLD may pose a risk for metabolic disturbances, cardiovascular morbidity or overall mortality. Secondary causes of hepatic steatosis are also needed to be ruled out in lean subjects with NAFLD. The effectiveness of various treatment modalities, such as exercise and pharmacotherapy, on lean NAFLD is not known. Weight loss is expected to help lean NAFLD patients who have visceral obesity. Further investigation is needed for many aspects of lean NAFLD, including mechanistic pathogenesis, risk assessment, natural history and therapeutic approach. PMID:28936403

Method for rubblizing an oil shale deposit for in situ retorting

DOEpatents

Lewis, Arthur E.

1977-01-01

A method for rubblizing an oil shale deposit that has been formed in alternate horizontal layers of rich and lean shale, including the steps of driving a horizontal tunnel along the lower edge of a rich shale layer of the deposit, sublevel caving by fan drilling and blasting of both rich and lean overlying shale layers at the distal end of the tunnel to rubblize the layers, removing a substantial amount of the accessible rubblized rich shale to permit the overlying rubblized lean shale to drop to tunnel floor level to form a column of lean shale, performing additional sublevel caving of rich and lean shale towards the proximate end of the tunnel, removal of a substantial amount of the additionally rubblized rich shale to allow the overlying rubblized lean shale to drop to tunnel floor level to form another column of rubblized lean shale, similarly performing additional steps of sublevel caving and removal of rich rubble to form additional columns of lean shale rubble in the rich shale rubble in the tunnel, and driving additional horizontal tunnels in the deposit and similarly rubblizing the overlying layers of rich and lean shale and forming columns of rubblized lean shale in the rich, thereby forming an in situ oil shale retort having zones of lean shale that remain permeable to hot retorting fluids in the presence of high rubble pile pressures and high retorting temperatures.

Relationship Between Lean Production and Operational Performance in the Manufacturing Industry

NASA Astrophysics Data System (ADS)

Rasi, Raja Zuraidah R. M.; Syamsyul Rakiman, Umol; Ahmad, Md Fauzi Bin

2015-05-01

Nowadays, more and more manufacturing firms have started to implement lean production system in their operations. Lean production viewed as one of the mechanism to maintain the organisation's position and to compete globally. However, many fail to apply the lean concepts successfully in their operations. Based on previous studies, implementation of lean production in the manufacturing industry is more focused on the relationship between Lean and Operational Performance of one dimension only. Therefore, this study attempted to examine the relationship between Lean Production (LP) and Operational Performance in 4 dimensions which are quality, delivery, cost and flexibility. This study employed quantitative study using questionnaires. Data was collected from 50 manufacturing industries. The data was analysed using Statistical Package for Social Science (SPSS) 22.0. This study is hoped to shed new understanding on the concept of Lean Production (LP) in regards of Operational Performance covering the 4 dimensions.

Influence of Geometry and Flow Variation on Jet Mixing and NO Formation in a Model Staged Combustor Mixer with Eight Orifices

NASA Technical Reports Server (NTRS)

Samuelsen, G. S.; Sowa, W. A.; Hatch, M. S.

1996-01-01

A series of non-reacting parametric experiments was conducted to investigate the effect of geometric and flow variations on mixing of cold jets in an axis-symmetric, heated cross flow. The confined, cylindrical geometries tested represent the quick mix region of a Rich-Burn/Quick-Mix/Lean-Burn (RQL) combustor. The experiments show that orifice geometry and jet to mainstream momentum-flux ratio significantly impact the mixing characteristic of jets in a cylindrical cross stream. A computational code was used to extrapolate the results of the non-reacting experiments to reacting conditions in order to examine the nitric oxide (NO) formation potential of the configurations examined. The results show that the rate of NO formation is highest immediately downstream of the injection plane. For a given momentum-flux ratio, the orifice geometry that mixes effectively in both the immediate vicinity of the injection plane, and in the wall regions at downstream locations, has the potential to produce the lowest NO emissions. The results suggest that further study may not necessarily lead to a universal guideline for designing a low NO mixer. Instead, an assessment of each application may be required to determine the optimum combination of momentum-flux ratio and orifice geometry to minimize NO formation. Experiments at reacting conditions are needed to verify the present results.

High intake of fatty fish, but not of lean fish, affects serum concentrations of TAG and HDL-cholesterol in healthy, normal-weight adults: a randomised trial.

PubMed

Hagen, Ingrid V; Helland, Anita; Bratlie, Marianne; Brokstad, Karl A; Rosenlund, Grethe; Sveier, Harald; Mellgren, Gunnar; Gudbrandsen, Oddrun A

2016-08-01

The aim of the present study was to examine whether high intake of lean or fatty fish (cod and farmed salmon, respectively) by healthy, normal-weight adults would affect risk factors of type 2 diabetes and CVD when compared with lean meat (chicken). More knowledge is needed concerning the potential health effects of high fish intake (>300 g/week) in normal-weight adults. In this randomised clinical trial, thirty-eight young, healthy, normal-weight participants consumed 750 g/week of lean or fatty fish or lean meat (as control) for 4 weeks at dinner according to provided recipes to ensure similar ways of preparations and choices of side dishes between the groups. Energy and macronutrient intakes at baseline and end point were similar in all groups, and there were no changes in energy and macronutrient intakes within any of the groups during the course of the study. High intake of fatty fish, but not lean fish, significantly reduced TAG and increased HDL-cholesterol concentrations in fasting serum when compared with lean meat intake. When compared with lean fish intake, fatty fish intake increased serum HDL-cholesterol. No differences were observed between lean fish, fatty fish and lean meat groups regarding fasting and postprandial glucose regulation. These findings suggest that high intake of fatty fish, but not of lean fish, could beneficially affect serum concentrations of TAG and HDL-cholesterol, which are CVD risk factors, in healthy, normal-weight adults, when compared with high intake of lean meat.

Stochastic approach to plasticity and yield in amorphous solids.

PubMed

Hentschel, H G E; Jaiswal, Prabhat K; Procaccia, Itamar; Sastry, Srikanth

2015-12-01

We focus on the probability distribution function (PDF) P(Δγ;γ) where Δγ are the measured strain intervals between plastic events in a athermal strained amorphous solids, and γ measures the accumulated strain. The tail of this distribution as Δγ→0 (in the thermodynamic limit) scales like Δγ(η). The exponent η is related via scaling relations to the tail of the PDF of the eigenvalues of the plastic modes of the Hessian matrix P(λ) which scales like λ(θ), η=(θ-1)/2. The numerical values of η or θ can be determined easily in the unstrained material and in the yielded state of plastic flow. Special care is called for in the determination of these exponents between these states as γ increases. Determining the γ dependence of the PDF P(Δγ;γ) can shed important light on plasticity and yield. We conclude that the PDF's of both Δγ and λ are not continuous functions of γ. In slowly quenched amorphous solids they undergo two discontinuous transitions, first at γ=0(+) and then at the yield point γ=γ(Y) to plastic flow. In quickly quenched amorphous solids the second transition is smeared out due to the nonexisting stress peak before yield. The nature of these transitions and scaling relations with the system size dependence of 〈Δγ〉 are discussed.

Debates Regarding Lean Patients with Polycystic Ovary Syndrome: A Narrative Review.

PubMed

Goyal, Manu; Dawood, Ayman S

2017-01-01

Polycystic ovary syndrome (PCOS) is a complex syndrome showing the clinical features of an endocrine/metabolic disorder, including hyperinsulinemia and hyperandrogenism. Two phenotypes are present, either lean or obese, with different biochemical, hormonal, and metabolic profiles. Evidence suggests many treatment modalities that can be applied. However, many of these modalities were found to be not suitable for the lean phenotype of PCOS. Much contradictory research was found regarding lean patients with PCOS. The aim of this narrative review is to shed light on the debate prevailing regarding characteristics, as well as metabolic, hematological, and potential management modalities. Literature review was performed from January 1, 2000 to March 31, 2017 with specific word search such as lean PCOS, hormonal abnormalities in lean PCOS, and the management of lean PCOS. All retrieved articles were carefully assessed, and data were obtained. We could conclude that the debate is still prevailing regarding this specific lean population with PCOS, especially with regard to their characteristics and management modalities. Further studies are still required to resolve this debate on the presence of PCOS in lean women.

Debates Regarding Lean Patients with Polycystic Ovary Syndrome: A Narrative Review

PubMed Central

Goyal, Manu; Dawood, Ayman S.

2017-01-01

Polycystic ovary syndrome (PCOS) is a complex syndrome showing the clinical features of an endocrine/metabolic disorder, including hyperinsulinemia and hyperandrogenism. Two phenotypes are present, either lean or obese, with different biochemical, hormonal, and metabolic profiles. Evidence suggests many treatment modalities that can be applied. However, many of these modalities were found to be not suitable for the lean phenotype of PCOS. Much contradictory research was found regarding lean patients with PCOS. The aim of this narrative review is to shed light on the debate prevailing regarding characteristics, as well as metabolic, hematological, and potential management modalities. Literature review was performed from January 1, 2000 to March 31, 2017 with specific word search such as lean PCOS, hormonal abnormalities in lean PCOS, and the management of lean PCOS. All retrieved articles were carefully assessed, and data were obtained. We could conclude that the debate is still prevailing regarding this specific lean population with PCOS, especially with regard to their characteristics and management modalities. Further studies are still required to resolve this debate on the presence of PCOS in lean women. PMID:29142442

Alcohol produces distinct hepatic lipidome and eicosanoid signature in lean and obese.

PubMed

Puri, Puneet; Xu, Jun; Vihervaara, Terhi; Katainen, Riikka; Ekroos, Kim; Daita, Kalyani; Min, Hae-Ki; Joyce, Andrew; Mirshahi, Faridoddin; Tsukamoto, Hidekazu; Sanyal, Arun J

2016-06-01

Alcohol- and obesity-related liver diseases often coexist. The hepatic lipidomics due to alcohol and obesity interaction is unknown. We characterized the hepatic lipidome due to 1) alcohol consumption in lean and obese mice and 2) obesity and alcohol interactions. In the French-Tsukamoto mouse model, intragastric alcohol or isocaloric dextrose were fed with either chow (lean) or high-fat, high-cholesterol diet (obese). Four groups (lean, lean alcohol, obese, and obese alcohol) were studied. MS was performed for hepatic lipidomics, and data were analyzed. Alcohol significantly increased hepatic cholesteryl esters and diacyl-glycerol in lean and obese but was more pronounced in obese. Alcohol produced contrasting changes in hepatic phospholipids with significant enrichment in lean mice versus significant decrease in obese mice, except phosphatidylglycerol, which was increased in both lean and obese alcohol groups. Most lysophospholipids were increased in lean alcohol and obese mice without alcohol use only. Prostaglandin E2; 5-, 8-, and 11-hydroxyeicosatetraenoic acids; and 9- and 13-hydroxyoctadecadienoic acids were considerably increased in obese mice with alcohol use. Alcohol consumption produced distinct changes in lean and obese with profound effects of obesity and alcohol interaction on proinflammatory and oxidative stress-related eicosanoids. Copyright © 2016 by the American Society for Biochemistry and Molecular Biology, Inc.

Loss of lean body mass affects low bone mineral density in patients with rheumatoid arthritis - results from the TOMORROW study.

PubMed

Okano, Tadashi; Inui, Kentaro; Tada, Masahiro; Sugioka, Yuko; Mamoto, Kenji; Wakitani, Shigeyuki; Koike, Tatsuya; Nakamura, Hiroaki

2017-11-01

Osteoporosis is one of the complications for patients with rheumatoid arthritis (RA). Rheumatoid cachexia, the loss of lean body mass, is another. However, the relationship between decreased lean body mass and reduced bone mineral density (BMD) in patients with RA has not been well studied. This study included 413 participants, comprising 208 patients with RA and 205 age- and sex-matched healthy volunteers. Clinical data, BMD, bone metabolic markers (BMM) and body composition, such as lean body mass and percent fat, were collected. Risk factors for osteoporosis in patients with RA including the relationship BMD and body composition were analyzed. Patients with RA showed low BMD and high BMM compared with controls. Moreover, lean body mass was lower and percent fat was higher in patients with RA. Lean body mass correlated positively and percent fat negatively with BMD. Lean body mass was a positive and disease duration was a negative independent factor for BMD in multivariate statistical analysis. BMD and lean body mass were significantly lower in patients with RA compared to healthy controls. Lean body mass correlated positively with BMD and decreased lean body mass and disease duration affected low BMD in patients with RA. [UMIN Clinical Trials Registry, http://www.umin.ac.jp/ctr/ , UMIN000003876].

Life history differences between fat and lean morphs of lake charr (Salvelinus namaycush) in Great Slave Lake, Northwest Territories, Canada

USGS Publications Warehouse

Hansen, Michael J.; Nate, Nancy A.; Chavarie, Louise; Muir, Andrew M.; Zimmerman, Mara S.; Krueger, Charles C.

2016-01-01

Life history characteristics (size, age, plumpness, buoyancy, survival, growth, and maturity) were compared between fat and lean morphs of lake charr Salvelinus namaycush in Great Slave Lake, Canada, to determine if differences may reflect effects of resource polymorphism. Lake charr were sampled using graded-mesh gill nets set in three depth strata. Of 236 lake charr captured, 122 were a fat morph and 114 were a lean morph. Males and females did not differ from each other in any attributes for either fat or lean morphs. The fat morph averaged 15 mm longer, 481 g heavier, and 4.7 years older than the lean morph. The fat morph averaged 26% heavier and 48% more buoyant at length than the lean morph. Survival of the fat morph was 1.7% higher than that of the lean morph. The fat morph grew at a slower annual rate to a shorter asymptotic length than the lean morph. Fat and lean morphs matured at similar lengths and ages. We concluded that the connection between resource polymorphism and life histories in lean versus fat lake charr suggests that morph-specific restoration objectives may be needed in lakes where lake charr diversity is considered to be a restoration goal.

Model Development and Process Analysis for Lean Cellular Design Planning in Aerospace Assembly and Manufacturing

NASA Astrophysics Data System (ADS)

Hilburn, Monty D.

Successful lean manufacturing and cellular manufacturing execution relies upon a foundation of leadership commitment and strategic planning built upon solid data and robust analysis. The problem for this study was to create and employ a simple lean transformation planning model and review process that could be used to identify functional support staff resources required to plan and execute lean manufacturing cells within aerospace assembly and manufacturing sites. The lean planning model was developed using available literature for lean manufacturing kaizen best practices and validated through a Delphi panel of lean experts. The resulting model and a standardized review process were used to assess the state of lean transformation planning at five sites of an international aerospace manufacturing and assembly company. The results of the three day, on-site review were compared with baseline plans collected from each of the five sites to determine if there analyzed, with focus on three critical areas of lean planning: the number and type of manufacturing cells identified, the number, type, and duration of planned lean and continuous kaizen events, and the quantity and type of functional staffing resources planned to support the kaizen schedule. Summarized data of the baseline and on-site reviews was analyzed with descriptive statistics. ANOVAs and paired-t tests at 95% significance level were conducted on the means of data sets to determine if null hypotheses related to cell, kaizen event, and support resources could be rejected. The results of the research found significant differences between lean transformation plans developed by site leadership and plans developed utilizing the structured, on-site review process and lean transformation planning model. The null hypothesis that there was no difference between the means of pre-review and on-site cell counts was rejected, as was the null hypothesis that there was no significant difference in kaizen event plans. These factors are critical inputs into the support staffing resources calculation used by the lean planning model. Null hypothesis related to functional support staff resources was rejected for most functional groups, indicating that the baseline site plan inadequately provided for cross-functional staff involvement to support the lean transformation plan. Null hypotheses related to total lean transformation staffing could not be rejected, indicating that while total staffing plans were not significantly different than plans developed during the on-site review and through the use of the lean planning model, the allocation of staffing among various functional groups such as engineering, production, and materials planning was an issue. The on-site review process and simple lean transformation plan developed was determined to be useful in identifying short-comings in lean transformation planning within aerospace manufacturing and assembly sites. It was concluded that the differences uncovered were likely contributing factors affecting the effectiveness of aerospace manufacturing sites' implementation of lean cellular manufacturing.

Large meta-analysis of genome-wide association studies identifies five loci for lean body mass.

PubMed

Zillikens, M Carola; Demissie, Serkalem; Hsu, Yi-Hsiang; Yerges-Armstrong, Laura M; Chou, Wen-Chi; Stolk, Lisette; Livshits, Gregory; Broer, Linda; Johnson, Toby; Koller, Daniel L; Kutalik, Zoltán; Luan, Jian'an; Malkin, Ida; Ried, Janina S; Smith, Albert V; Thorleifsson, Gudmar; Vandenput, Liesbeth; Hua Zhao, Jing; Zhang, Weihua; Aghdassi, Ali; Åkesson, Kristina; Amin, Najaf; Baier, Leslie J; Barroso, Inês; Bennett, David A; Bertram, Lars; Biffar, Rainer; Bochud, Murielle; Boehnke, Michael; Borecki, Ingrid B; Buchman, Aron S; Byberg, Liisa; Campbell, Harry; Campos Obanda, Natalia; Cauley, Jane A; Cawthon, Peggy M; Cederberg, Henna; Chen, Zhao; Cho, Nam H; Jin Choi, Hyung; Claussnitzer, Melina; Collins, Francis; Cummings, Steven R; De Jager, Philip L; Demuth, Ilja; Dhonukshe-Rutten, Rosalie A M; Diatchenko, Luda; Eiriksdottir, Gudny; Enneman, Anke W; Erdos, Mike; Eriksson, Johan G; Eriksson, Joel; Estrada, Karol; Evans, Daniel S; Feitosa, Mary F; Fu, Mao; Garcia, Melissa; Gieger, Christian; Girke, Thomas; Glazer, Nicole L; Grallert, Harald; Grewal, Jagvir; Han, Bok-Ghee; Hanson, Robert L; Hayward, Caroline; Hofman, Albert; Hoffman, Eric P; Homuth, Georg; Hsueh, Wen-Chi; Hubal, Monica J; Hubbard, Alan; Huffman, Kim M; Husted, Lise B; Illig, Thomas; Ingelsson, Erik; Ittermann, Till; Jansson, John-Olov; Jordan, Joanne M; Jula, Antti; Karlsson, Magnus; Khaw, Kay-Tee; Kilpeläinen, Tuomas O; Klopp, Norman; Kloth, Jacqueline S L; Koistinen, Heikki A; Kraus, William E; Kritchevsky, Stephen; Kuulasmaa, Teemu; Kuusisto, Johanna; Laakso, Markku; Lahti, Jari; Lang, Thomas; Langdahl, Bente L; Launer, Lenore J; Lee, Jong-Young; Lerch, Markus M; Lewis, Joshua R; Lind, Lars; Lindgren, Cecilia; Liu, Yongmei; Liu, Tian; Liu, Youfang; Ljunggren, Östen; Lorentzon, Mattias; Luben, Robert N; Maixner, William; McGuigan, Fiona E; Medina-Gomez, Carolina; Meitinger, Thomas; Melhus, Håkan; Mellström, Dan; Melov, Simon; Michaëlsson, Karl; Mitchell, Braxton D; Morris, Andrew P; Mosekilde, Leif; Newman, Anne; Nielson, Carrie M; O'Connell, Jeffrey R; Oostra, Ben A; Orwoll, Eric S; Palotie, Aarno; Parker, Stephen C J; Peacock, Munro; Perola, Markus; Peters, Annette; Polasek, Ozren; Prince, Richard L; Räikkönen, Katri; Ralston, Stuart H; Ripatti, Samuli; Robbins, John A; Rotter, Jerome I; Rudan, Igor; Salomaa, Veikko; Satterfield, Suzanne; Schadt, Eric E; Schipf, Sabine; Scott, Laura; Sehmi, Joban; Shen, Jian; Soo Shin, Chan; Sigurdsson, Gunnar; Smith, Shad; Soranzo, Nicole; Stančáková, Alena; Steinhagen-Thiessen, Elisabeth; Streeten, Elizabeth A; Styrkarsdottir, Unnur; Swart, Karin M A; Tan, Sian-Tsung; Tarnopolsky, Mark A; Thompson, Patricia; Thomson, Cynthia A; Thorsteinsdottir, Unnur; Tikkanen, Emmi; Tranah, Gregory J; Tuomilehto, Jaakko; van Schoor, Natasja M; Verma, Arjun; Vollenweider, Peter; Völzke, Henry; Wactawski-Wende, Jean; Walker, Mark; Weedon, Michael N; Welch, Ryan; Wichmann, H-Erich; Widen, Elisabeth; Williams, Frances M K; Wilson, James F; Wright, Nicole C; Xie, Weijia; Yu, Lei; Zhou, Yanhua; Chambers, John C; Döring, Angela; van Duijn, Cornelia M; Econs, Michael J; Gudnason, Vilmundur; Kooner, Jaspal S; Psaty, Bruce M; Spector, Timothy D; Stefansson, Kari; Rivadeneira, Fernando; Uitterlinden, André G; Wareham, Nicholas J; Ossowski, Vicky; Waterworth, Dawn; Loos, Ruth J F; Karasik, David; Harris, Tamara B; Ohlsson, Claes; Kiel, Douglas P

2017-07-19

Lean body mass, consisting mostly of skeletal muscle, is important for healthy aging. We performed a genome-wide association study for whole body (20 cohorts of European ancestry with n = 38,292) and appendicular (arms and legs) lean body mass (n = 28,330) measured using dual energy X-ray absorptiometry or bioelectrical impedance analysis, adjusted for sex, age, height, and fat mass. Twenty-one single-nucleotide polymorphisms were significantly associated with lean body mass either genome wide (p < 5 × 10 -8 ) or suggestively genome wide (p < 2.3 × 10 -6 ). Replication in 63,475 (47,227 of European ancestry) individuals from 33 cohorts for whole body lean body mass and in 45,090 (42,360 of European ancestry) subjects from 25 cohorts for appendicular lean body mass was successful for five single-nucleotide polymorphisms in/near HSD17B11, VCAN, ADAMTSL3, IRS1, and FTO for total lean body mass and for three single-nucleotide polymorphisms in/near VCAN, ADAMTSL3, and IRS1 for appendicular lean body mass. Our findings provide new insight into the genetics of lean body mass.Lean body mass is a highly heritable trait and is associated with various health conditions. Here, Kiel and colleagues perform a meta-analysis of genome-wide association studies for whole body lean body mass and find five novel genetic loci to be significantly associated.

Serum Predictors of Percent Lean Mass in Young Adults.

PubMed

Lustgarten, Michael S; Price, Lori L; Phillips, Edward M; Kirn, Dylan R; Mills, John; Fielding, Roger A

2016-08-01

Lustgarten, MS, Price, LL, Phillips, EM, Kirn, DR, Mills, J, and Fielding, RA. Serum predictors of percent lean mass in young adults. J Strength Cond Res 30(8): 2194-2201, 2016-Elevated lean (skeletal muscle) mass is associated with increased muscle strength and anaerobic exercise performance, whereas low levels of lean mass are associated with insulin resistance and sarcopenia. Therefore, studies aimed at obtaining an improved understanding of mechanisms related to the quantity of lean mass are of interest. Percent lean mass (total lean mass/body weight × 100) in 77 young subjects (18-35 years) was measured with dual-energy x-ray absorptiometry. Twenty analytes and 296 metabolites were evaluated with the use of the standard chemistry screen and mass spectrometry-based metabolomic profiling, respectively. Sex-adjusted multivariable linear regression was used to determine serum analytes and metabolites significantly (p ≤ 0.05 and q ≤ 0.30) associated with the percent lean mass. Two enzymes (alkaline phosphatase and serum glutamate oxaloacetate aminotransferase) and 29 metabolites were found to be significantly associated with the percent lean mass, including metabolites related to microbial metabolism, uremia, inflammation, oxidative stress, branched-chain amino acid metabolism, insulin sensitivity, glycerolipid metabolism, and xenobiotics. Use of sex-adjusted stepwise regression to obtain a final covariate predictor model identified the combination of 5 analytes and metabolites as overall predictors of the percent lean mass (model R = 82.5%). Collectively, these data suggest that a complex interplay of various metabolic processes underlies the maintenance of lean mass in young healthy adults.

Healthcare Lean.

PubMed

Long, John C

2003-01-01

Lean Thinking is an integrated approach to designing, doing and improving the work of people that have come together to produce and deliver goods, services and information. Healthcare Lean is based on the Toyota production system and applies concepts and techniques of Lean Thinking to hospitals and physician practices.

Case study of lean manufacturing application in a die casting manufacturing company

NASA Astrophysics Data System (ADS)

Ching, Ng Tan; Hoe, Clarence Chan Kok; Hong, Tang Sai; Ghobakhloo, Morteza; Pin, Chen Kah

2015-05-01

The case study of lean manufacturing aims to study the application of lean manufacturing in a die casting manufacturing company located in Pulau Penang, Malaysia. This case study describes mainly about the important concepts and applications of lean manufacturing which could gradually help the company in increasing the profit by studying and analyzing their current manufacturing process and company culture. Many approaches of lean manufacturing are studied in this project which includes: 5S housekeeping, Kaizen, and Takt Time. Besides, the lean tools mentioned, quality tool such as the House of Quality is being used as an analysis tool to continuously improve the product quality. In short, the existing lean culture in the company is studied and analyzed, with recommendations written at the end of this paper.

Does Lean healthcare improve patient satisfaction? A mixed-method investigation into primary care.

PubMed

Poksinska, Bozena Bonnie; Fialkowska-Filipek, Malgorzata; Engström, Jon

2017-02-01

Lean healthcare is claimed to contribute to improved patient satisfaction, but there is limited evidence to support this notion. This study investigates how primary-care centres working with Lean define and improve value from the patient's perspective, and how the application of Lean healthcare influences patient satisfaction. This paper contains two qualitative case studies and a quantitative study based on results from the Swedish National Patient Survey. Through the case studies, we investigated how primary-care organisations realised the principle of defining and improving value from the patient's perspective. In the quantitative study, we compared results from the patient satisfaction survey for 23 primary-care centres working with Lean with a control group of 23 care centres not working with Lean. We also analysed changes in patient satisfaction over time. Our case studies reveal that Lean healthcare implementations primarily target efficiency and little attention is paid to the patient's perspective. The quantitative study shows no significantly better results in patient satisfaction for primary-care centres working with Lean healthcare compared with those not working with Lean. Further, care centres working with Lean show no significant improvements in patient satisfaction over time. Lean healthcare implementations seem to have a limited impact on improving patient satisfaction. Care providers need to pay more attention to integrating the patient's perspective in the application of Lean healthcare. Value needs to be defined and value streams need to be improved based on both the knowledge and clinical expertise of care providers, and the preferences and needs of patients. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Implementing Lean Manufacturing in Malaysian Small and Medium Startup Pharmaceutical Company

NASA Astrophysics Data System (ADS)

Ibrahim, Wan Mohd Khairi bin Wan; Rahman, Mohamed Abdul; Abu Bakar, Mohd Rushdi bin

2017-03-01

Domestic pharmaceutical industry has been identified by the Malaysian government as an industry to be developed under its 11th economic development plan. Most homegrown pharmaceutical companies fall under the category of small and medium enterprises (SME) and therefore need to be highly efficient in their operations to compete with the multinationals. Though lean manufacturing is a well-known methodology to achieve an efficient operation, only a small percentage of the local SMEs implement it. The study aims to determine the real success factors in lean implementation through systematic review of relevant literature on lean manufacturing implementation in local companies, onsite observation of a selected SME company, Global Factor Sdn. Bhd. (GFSB), that successfully implemented lean manufacturing followed by actual implementation of lean project at IKOP Sdn. Bhd., a small startup pharmaceutical company. Lean tools like Gemba, value stream map (VSM) and spaghetti diagram were used to analyze and improve a process at IKOP Sdn. Bhd. The literature review showed that the implementation of lean manufacturing at Malaysian SMEs involved in pharmaceutical industry is at its infancy. Study at GFSB indicated that successful implementation of lean manufacturing stems from management support, employee’s commitment, government support and knowledge on lean among employees. Application of lean tools in IKOP Sdn. Bhd. to improve the process cycle efficiency of hand sanitizer, i-Hand 4.0, has shown that the GMP guidelines are not jeopardized. The Kaizen improvement project resulted in 46.3% reduction in lead time. It may be concluded that implementing lean manufacturing in any small local startup pharmaceutical company is beneficial in reducing operational costs and increasing the efficiency and effectiveness and does not conflict with the existing GMP guidelines.

Implementing lean in Malaysian universities: Lean awareness level in an engineering faculty of a local university

NASA Astrophysics Data System (ADS)

Azim Khairi, M.; Rahman, Mohamed Abd

2018-01-01

Many academic articles were published in Malaysia promoting the goodness of lean in manufacturing and industrial sectors but less attention was apparently given to the possibility of obtaining the same universal benefits when applying lean in non-manufacturing sectors especially higher education. This study aims to determine the level of lean awareness among a local university’s community taking its Faculty of Engineering (FoE) as the case study. It also seeks to identify typical FoE’s staff perception on lean regarding its benefits and the obstacles in implementing it. A web-based survey using questionnaires was carried out for 215 respondents consisting of academic and administrative staff of the faculty. Statistical Package for the Social Science (SPSS) was used to analyze the survey data collected. A total of 13.95% of respondents returned the forms. Slightly more than half of those responded (56.7%) have encountered some of the lean terms with mean 1.43 and standard deviation 0.504. However, the large amount of standard deviation somewhat indicates that the real level of lean awareness of FoE as a group was low. In terms of lean benefits, reduction of waste was favored (93.3%) by the respondents with mean 0.93 and standard deviation 0.254. For obstacles in implementing lean, lack of knowledge was selected by most respondents (86.7%) to be the major factor with mean 0.87 and standard deviation 0.346. Through the analysis done, the study may conclude that level of lean awareness among the university‘s community was low thus may hinder implementation of lean concept.

Four-way-leaning test shows larger limits of stability than a circular-leaning test.

PubMed

Thomsen, Mikkel Højgaard; Støttrup, Nicolai; Larsen, Frederik Greve; Pedersen, Ann-Marie Sydow Krogh; Poulsen, Anne Grove; Hirata, Rogerio Pessoto

2017-01-01

Limits of stability (LOS) have extensive clinical and rehabilitational value yet no standard consensus on measuring LOS exists. LOS measured using a leaning or a circling protocol is commonly used in research and clinical settings, however differences in protocols and reliability problems exist. This study measured LOS using a four-way-leaning test and a circular-leaning test to test which showed larger LOS measurements. Furthermore, number of adaptation trials needed for consistent results was assessed. Limits of stability were measured using a force plate (Metitur Good Balance System ® ) sampling at 50Hz. Thirty healthy subjects completed 30 trials assessing LOS alternating between four-way-leaning test and circular-leaning test. A main effect of methods (ANOVA:F(1,28)=45.86, P<0.01) with the four-way-leaning test showing larger values than the circular-leaning test (NK, P<0.01). An interaction between method×directions was found (ANOVA:F(3, 84)=24.87, P<0.01). The four-way-leaning test showed larger LOS in anterior (NK, P<0.05), right (NK, P<0.01) and left direction (NK, P<0.01). Analysis of LOS for the four-way-leaning test showed a difference between trials (ANOVA:F(14,392)=7.81, P<0.01). Differences were found between trial 1 and 7 (NK, P<0.03), trial 6 and 8 (NK, P<0.02) and trial 7 and 15 (NK, P<0.02). Four-way-leaning test showed high correlation (ICC>0.87) between first and second trial for all directions. Four-way-leaning test yields larger LOS in anterior, right and left direction making it more reliable when measuring LOS. A learning effect was found up to the 8th trial, which suggests using 8 adaptation trials before reliable LOS is measured. Copyright © 2016 Elsevier B.V. All rights reserved.

Correlates of increased lean muscle mass in women with polycystic ovary syndrome.

PubMed

Carmina, E; Guastella, E; Longo, R A; Rini, G B; Lobo, R A

2009-10-01

Muscle mass plays an important role in determining cardiovascular and metabolic risks in polycystic ovary syndrome (PCOS). In addition, whether lean mass influences carotid intima-media thickness (IMT) in PCOS has not been assessed. Prospective investigation. Ninety-five women with PCOS were age- and weight-matched to 90 ovulatory controls. All women had dual X-ray absorptiometry for lean, fat and bone mass, and bone mass density (BMD). Serum testosterone, sex hormone-binding globulin, insulin, and glucose and carotid IMT were determined. Free androgen index (FAI) and insulin resistance (by QUICKI) were calculated. In PCOS, waist circumference and insulin were higher and QUICKI lower than in controls (P<0.01). Trunk fat mass, % trunk fat, and lean mass were higher in PCOS compared to controls (P<0.01), while total bone mass and BMD were similar. IMT was increased in PCOS (P<0.01) but only 15% of PCOS patients had abnormal (> or = 0.9 mm) values. Lean mass correlated with fat parameters, insulin, QUICKI, and FAI, but not with total testosterone; and after adjustments for insulin and QUICKI, lean mass still correlated with fat mass (P<0.01) but not FAI. Lean mass correlated with IMT (P<0.01), but this was dependent on insulin. However, excluding those patients with abnormal IMT values, IMT correlated with lean mass independently of insulin. Bone mass correlated with lean and fat mass, but not with insulin or androgen. PCOS patients with 'pathological' IMT values had higher % trunk fat, lean mass, and insulin, lower QUICKI, and higher testosterone and FAI compared with those with normal IMT. Lean mass is increased in PCOS, while bone mass is similar to that of matched controls. The major correlates of lean mass are fat mass and insulin but not androgen. Lean mass also correlated with IMT, and although influenced by insulin, small changes in IMT may partially reflect changes in muscle mass, while clearly abnormal values relate to more severe abnormalities of PCOS.

7 CFR 59.200 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-01-01

... these same swine. Average lean percentage. The term “average lean percentage” means the value equal to the average percentage of the carcass weight comprised of lean meat for the swine slaughtered during the applicable reporting period. Whenever the packer changes the manner in which the average lean...

7 CFR 59.200 - Definitions.

Code of Federal Regulations, 2012 CFR

2012-01-01

... these same swine. Average lean percentage. The term “average lean percentage” means the value equal to the average percentage of the carcass weight comprised of lean meat for the swine slaughtered during the applicable reporting period. Whenever the packer changes the manner in which the average lean...

The human side of lean teams.

PubMed

Wackerbarth, Sarah B; Strawser-Srinath, Jamie R; Conigliaro, Joseph C

2015-05-01

Organizations use lean principles to increase quality and decrease costs. Lean projects require an understanding of systems-wide processes and utilize interdisciplinary teams. Most lean tools are straightforward, and the biggest barrier to successful implementation is often development of the team aspect of the lean approach. The purpose of this article is to share challenges experienced by a lean team charged with improving a hospital discharge process. Reflection on the experience provides an opportunity to highlight lessons from The Team Handbook by Peter Scholtes and colleagues. To improve the likelihood that process improvement initiatives, including lean projects, will be successful, organizations should consider providing training in organizational change principles and team building. The authors' lean team learned these lessons the hard way. Despite the challenges, the team successfully implemented changes throughout the organization that have had a positive impact. Training to understand the psychology of change might have decreased the resistance faced in implementing these changes. © 2014 by the American College of Medical Quality.

Lean practices for quality results: a case illustration.

PubMed

Hwang, Pauline; Hwang, David; Hong, Paul

2014-01-01

Increasingly, healthcare providers are implementing lean practices to achieve quality results. Implementing lean healthcare practices is unique compared to manufacturing and other service industries. The purpose of this paper is to present a model that identifies and defines the lean implementation key success factors in healthcare organisations. The model is based on an extant literature review and a case illustration that explores actual lean implementation in a major USA hospital located in a Midwestern city (approximately 300,000 people). An exploratory/descriptive study using observation and follow-up interviews was conducted to identify lean practices in the hospital. Lean practice key drivers include growing elderly populations, rising medical expenses, decreasing insurance coverage and decreasing management support. Effectively implementing lean practices to increase bottom-line results and improve organisational integrity requires sharing goals and processes among healthcare managers and professionals. An illustration explains the model and the study provides a sound foundation for empirical work. Practical implications are included. Lean practices minimise waste and unnecessary hospital stays while simultaneously enhancing customer values and deploying resources in supply systems. Leadership requires clear project targets based on sound front-end planning because initial implementation steps involve uncertainty and ambiguity (i.e. fuzzy front-end planning). Since top management support is crucial for implementing lean practices successfully, a heavyweight manager, who communicates well both with top managers and project team members, is an important success factor when implementing lean practices. Increasingly, green orientation and sustainability initiatives are phrases that replaced lean practices. Effective results; e.g. waste reduction, employee satisfaction and customer values are applicable to bigger competitive challenges arising both in specific organisations and inter-organisational networks. Healthcare managers are adopting business practices that improve efficiency and productivity while ensuring their healthcare mission and guaranteeing that customer values are achieved. Shared understanding about complex goals (e.g. reducing waste and enhancing customer value) at the front-end is crucial for implementing successful lean practices. In particular, this study shows that nursing practices, which are both labour intensive and technology enabled, are good candidates for lean practice.

Applying lean management principles to the creation of a postpartum hemorrhage care bundle.

PubMed

Faulkner, Beth

2013-10-01

A lean management process is a set of interventions, each of which creates value for the customer. Lean management is not a new concept, but is relatively new to health care. Postpartum hemorrhage (PPH) is the most common cause of maternal death worldwide in both developing and developed countries. We applied lean management principles as an innovative approach to improving outcomes in patients with PPH. Initial results using principles of lean management indicated significant improvements in response time and family-centered care. When applied rigorously and throughout the organization, lean principles can have a dramatic effect on productivity, cost and quality. © 2013 AWHONN.

Escape from rich-to-lean transitions: Stimulus change and timeout.

PubMed

Retzlaff, Billie J; Parthum, Elizabeth T P; Pitts, Raymond C; Hughes, Christine E

2017-01-01

Extended pausing during discriminable transitions from rich-to-lean conditions can be viewed as escape (i.e., rich-to-lean transitions function aversively). In the current experiments, pigeons' key pecking was maintained by a multiple fixed-ratio fixed-ratio schedule of rich or lean reinforcers. Pigeons then were provided with another, explicit, mechanism of escape by changing the stimulus from the transition-specific stimulus used in the multiple schedule to a mixed-schedule stimulus (Experiment 1) or by producing a period of timeout in which the stimulus was turned off and the schedule was suspended (Experiment 2). Overall, escape was under joint control of past and upcoming reinforcer magnitudes, such that responses on the escape key were most likely during rich-to-lean transitions, and second-most likely during lean-to-lean transitions. Even though pigeons pecked the escape key, they paused before doing so, and the latency to begin the fixed ratio (i.e., the pause) remained extended during rich-to-lean transitions. These findings suggest that although the stimulus associated with rich-to-lean transitions functioned aversively, pausing is more than simply escape responding from the stimulus. © 2017 Society for the Experimental Analysis of Behavior.

LEAN thinking in Finnish healthcare.

PubMed

Jorma, Tapani; Tiirinki, Hanna; Bloigu, Risto; Turkki, Leena

2016-01-01

Purpose - The purpose of this study is to evaluate how LEAN thinking is used as a management and development tool in the Finnish public healthcare system and what kind of outcomes have been achieved or expected by using it. The main focus is in managing and developing patient and treatment processes. Design/methodology/approach - A mixed-method approach incorporating the Webropol survey was used. Findings - LEAN is quite a new concept in Finnish public healthcare. It is mainly used as a development tool to seek financial savings and to improve the efficiency of patient processes, but has not yet been deeply implemented. However, the experiences from LEAN initiatives have been positive, and the methodology is already quite well-known. It can be concluded that, because of positive experiences from LEAN, the environment in Finnish healthcare is ready for the deeper implementation of LEAN. Originality/value - This paper evaluates the usage of LEAN thinking for the first time in the public healthcare system of Finland as a development tool and a management system. It highlights the implementation and achieved results of LEAN thinking when used in the healthcare environment. It also highlights the expectations for LEAN thinking in Finnish public healthcare.

The Role of the Clinical Laboratory in the Future of Health Care: Lean Microbiology

PubMed Central

Samuel, Linoj

2014-01-01

This commentary will introduce lean concepts into the clinical microbiology laboratory. The practice of lean in the clinical microbiology laboratory can remove waste, increase efficiency, and reduce costs. Lean, Six Sigma, and other such management initiatives are useful tools and can provide dividends but must be accompanied by organizational leadership commitment to sustaining the lean culture in the laboratory setting and providing resources and time to work through the process. PMID:24574289

Apparatus and method for burning a lean, premixed fuel/air mixture with low NOx emission

DOEpatents

Kostiuk, Larry W.; Cheng, Robert K.

1996-01-01

An apparatus for enabling a burner to stably burn a lean fuel/air mixture. The burner directs the lean fuel/air mixture in a stream. The apparatus comprises an annular flame stabilizer; and a device for mounting the flame stabilizer in the fuel/air mixture stream. The burner may include a body having an internal bore, in which case, the annular flame stabilizer is shaped to conform to the cross-sectional shape of the bore, is spaced from the bore by a distance greater than about 0.5 mm, and the mounting device mounts the flame stabilizer in the bore. An apparatus for burning a gaseous fuel with low NOx emissions comprises a device for premixing air with the fuel to provide a lean fuel/air mixture; a nozzle having an internal bore through which the lean fuel/air mixture passes in a stream; and a flame stabilizer mounted in the stream of the lean fuel/air mixture. The flame stabilizer may be mounted in the internal bore, in which case, it is shaped and is spaced from the bore as just described. In a method of burning a lean fuel/air mixture, a lean fuel/air mixture is provided, and is directed in a stream; an annular eddy is created in the stream of the lean fuel/air mixture; and the lean fuel/air mixture is ignited at the eddy.

The current state of Lean implementation in health care: literature review.

PubMed

Poksinska, Bozena

2010-01-01

The purpose of this article is to discuss the current state of implementation of Lean production in health care. The study focuses on the definition of Lean in health care and implementation process, barriers, challenges, enablers, and outcomes of implementing Lean production methods in health care. A comprehensive search of the literature concerning the implementation of Lean production in health care was used to generate a synthesis of the literature around the chosen research questions. Lean production in health care is mostly used as a process improvement approach and focuses on 3 main areas: (1) defining value from the patient point of view, (2) mapping value streams, and (3) eliminating waste in an attempt to create continuous flow. Value stream mapping is the most frequently applied Lean tool in health care. The usual implementation steps include conducting Lean training, initiating pilot projects, and implementing improvements using interdisciplinary teams. One of the barriers is lack of educators and consultants who have their roots in the health care sector and can provide support by sharing experience and giving examples from real-life applications of Lean in health care. The enablers of Lean in health care seem not to be different from the enablers of any other change initiative. The outcomes can be divided into 2 broad areas: the performance of the health care system and the development of employees and work environment.

Do patients with knee osteoarthritis perform sit-to-stand motion efficiently?

PubMed

Anan, Masaya; Shinkoda, Koichi; Suzuki, Kentaro; Yagi, Masahide; Ibara, Takuya; Kito, Nobuhiro

2015-02-01

The sit-to-stand motion (STS) is a frequently executed activity that is affected by weakness in the quadriceps femoris muscle and knee joint pain in patients with knee osteoarthritis (OA). We investigated whether patients with knee OA can efficiently perform STS through mechanical energy transfer assessments. Participants were 20 women with knee OA and 17 age-matched asymptomatic controls. The center of mass (COM), segment angles, joint moments, and powers during STS were measured. The negative mechanical work in the proximal portion of the shank, negative mean powers in the distal portion of the pelvis and proximal portion of the shank, and the positive mean power in the proximal and distal portions of the thigh were significantly lower in the knee OA group than in the control group. Patients with knee OA primarily performed thoracic forward lean movement, shifting their COM closer to the base of support provided by the feet alone, in an attempt to achieve stability at and after buttocks-off. However, control ability, which generates and absorbs kinetic energy quickly, was not enhanced in these patients, and their motion was unable to increase absorption of the mechanical energy in hip extensors and reduce the load on knee extensors. Furthermore, STS in patients with knee OA had reduced energy absorption in the knee extensors from the shank forward lean movement after buttocks-off, had reduced knee extensor efficiency, and made greater use of physiological energy. These findings suggest that, from the standpoint of mechanical energy transfer, patients with knee OA do not perform STS efficiently. Copyright © 2014 Elsevier B.V. All rights reserved.

Odel of Dynamic Integration of Lean Shop Floor Management Within the Organizational Management System

NASA Astrophysics Data System (ADS)

Iuga, Virginia; Kifor, Claudiu

2014-12-01

The key to achieve a sustainable development lies in the customer satisfaction through improved quality, reduced cost, reduced delivery lead times and proper communication. The objective of the lean manufacturing system (LMS) is to identify and eliminate the processes and resources which do not add value to a product. The following paper aims to present a proposal of further development of integrated management systems in organizations through the implementation of lean shop floor management. In the first part of the paper, a dynamic model of the implementation steps will be presented. Furthermore, the paper underlines the importance of implementing a lean culture parallel with each step of integrating the lean methods and tools. The paper also describes the Toyota philosophy, tools, and the supporting lean culture necessary to implementing an efficient lean system in productive organizations

Packages of participation: Swedish employees’ experience of Lean depends on how they are involved

PubMed Central

Brännmark, Mikael; Holden, Richard J.

2013-01-01

Background Lean Production is a dominant approach in Swedish and global manufacturing and service industries. Studies of Lean’s employee effects are few and contradictory. Purpose Employee effects from Lean are likely not uniform. This paper investigates the effect of employees' participation on their experiences of Lean. Method This study investigated how different packages of employee participation in Lean affected manufacturing workers’ experiences of Lean. During 2008–2011, qualitative and quantitative data were collected from Swedish manufacturing companies participating in the national Swedish Lean Production program Produktionslyftet. Data from 129 surveys (28 companies), 39 semi-structured interviews, and 30 reports were analyzed. In the main analysis, comparisons were made of the survey-reported Lean experiences of employees in three groups: temporary group employees (N = 36), who participated in Lean mostly through intermittent projects; continuous group employees (N = 69), who participated through standing improvement groups; and combined group employees (N = 24), who participated in both ways. Results Continuous group employees had the most positive experience of Lean, followed by the combined group. Temporary group employees had the least positive experiences, being less likely than their counterparts to report that Lean improved teamwork, occupational safety, and change-related learning, decision making, and authority. Conclusions These findings support the importance of continuous, structured opportunities for participation but raise the possibility that more participation may result in greater workload and role overload, mitigating some benefits of employee involvement. Consequently, companies should consider involving employees in change efforts but should attend to the specific design of participation activities. PMID:24665370

Roadmap for Lean implementation in Indian automotive component manufacturing industry: comparative study of UNIDO Model and ISM Model

NASA Astrophysics Data System (ADS)

Jadhav, J. R.; Mantha, S. S.; Rane, S. B.

2015-06-01

The demands for automobiles increased drastically in last two and half decades in India. Many global automobile manufacturers and Tier-1 suppliers have already set up research, development and manufacturing facilities in India. The Indian automotive component industry started implementing Lean practices to fulfill the demand of these customers. United Nations Industrial Development Organization (UNIDO) has taken proactive approach in association with Automotive Component Manufacturers Association of India (ACMA) and the Government of India to assist Indian SMEs in various clusters since 1999 to make them globally competitive. The primary objectives of this research are to study the UNIDO-ACMA Model as well as ISM Model of Lean implementation and validate the ISM Model by comparing with UNIDO-ACMA Model. It also aims at presenting a roadmap for Lean implementation in Indian automotive component industry. This paper is based on secondary data which include the research articles, web articles, doctoral thesis, survey reports and books on automotive industry in the field of Lean, JIT and ISM. ISM Model for Lean practice bundles was developed by authors in consultation with Lean practitioners. The UNIDO-ACMA Model has six stages whereas ISM Model has eight phases for Lean implementation. The ISM-based Lean implementation model is validated through high degree of similarity with UNIDO-ACMA Model. The major contribution of this paper is the proposed ISM Model for sustainable Lean implementation. The ISM-based Lean implementation framework presents greater insight of implementation process at more microlevel as compared to UNIDO-ACMA Model.

Plasma spraying method for forming diamond and diamond-like coatings

DOEpatents

Holcombe, C.E.; Seals, R.D.; Price, R.E.

1997-06-03

A method and composition is disclosed for the deposition of a thick layer of diamond or diamond-like material. The method includes high temperature processing wherein a selected composition including at least glassy carbon is heated in a direct current plasma arc device to a selected temperature above the softening point, in an inert atmosphere, and is propelled to quickly quenched on a selected substrate. The softened or molten composition crystallizes on the substrate to form a thick deposition layer comprising at least a diamond or diamond-like material. The selected composition includes at least glassy carbon as a primary constituent and may include at least one secondary constituent. Preferably, the secondary constituents are selected from the group consisting of at least diamond powder, boron carbide (B{sub 4}C) powder and mixtures thereof. 9 figs.

An authentic imaging probe to track cell fate from beginning to end.

PubMed

Lee, Seung Koo; Mortensen, Luke J; Lin, Charles P; Tung, Ching-Hsuan

2014-10-17

Accurate tracing of cell viability is critical for optimizing delivery methods and evaluating the efficacy and safety of cell therapeutics. A nanoparticle-based cell tracker is developed to image cell fate from live to dead. The particle is fabricated from two types of optically quenched polyelectrolytes, a life indicator and a death indicator, through electrostatic interactions. On incubation with cells, the fabricated bifunctional nanoprobes are taken up efficiently and the first colour is produced by normal intracellular proteolysis, reflecting the healthy status of the cells. Depending on the number of coated layers, the signal can persist for several replication cycles. However, as the cells begin dying, the second colour appears quickly to reflect the new cell status. Using this chameleon-like cell tracker, live cells can be distinguished from apoptotic and necrotic cells instantly and definitively.

Lean blowoff detection sensor

DOEpatents

Thornton, Jimmy [Morgantown, WV; Straub, Douglas L [Morgantown, WV; Chorpening, Benjamin T [Morgantown, WV; Huckaby, David [Morgantown, WV

2007-04-03

Apparatus and method for detecting incipient lean blowoff conditions in a lean premixed combustion nozzle of a gas turbine. A sensor near the flame detects the concentration of hydrocarbon ions and/or electrons produced by combustion and the concentration monitored as a function of time are used to indicate incipient lean blowoff conditions.

What Do Organizational Leaders Need from Lean Graduate Programming

ERIC Educational Resources Information Center

Flumerfelt, Shannon; Alves, Anabela Carvalho; Leão, Celina Pinto; Wade, Dennis L.

2016-01-01

Purpose: This paper aims to assess the needs for a lean continuous improvement professional certificate and/or lean leadership cognate for a Doctorate of Education in leadership focused in three main research questions: "What do organizational leaders need from a Lean graduate programming?"; "What are the preferable methods of…

Getting 'Lean': hardwiring process excellence into Northeast Health.

PubMed

Brown, Tricia; Duthe, Robert

2009-01-01

Many healthcare organizations are turning to the "Lean" Toyota Production System as a means to hardwire process excellence into their organizations. Northeast Health, an integrated delivery system in New York's capital region, introduced the Lean concept into its culture in 2004. After four years, the organization is beginning to see its staff hardwire Lean thinking into day-to-day behaviors. This paper focuses on the approach used by Northeast Health to introduce Lean concepts into its culture, challenges faced, lessons learned and the factors critical to success.

Application of a mathematical model for ergonomics in lean manufacturing.

PubMed

Botti, Lucia; Mora, Cristina; Regattieri, Alberto

2017-10-01

The data presented in this article are related to the research article "Integrating ergonomics and lean manufacturing principles in a hybrid assembly line" (Botti et al., 2017) [1]. The results refer to the application of the mathematical model for the design of lean processes in hybrid assembly lines, meeting both the lean principles and the ergonomic requirements for safe assembly work. Data show that the success of a lean strategy is possible when ergonomics of workers is a parameter of the assembly process design.

Advanced engine management of individual cylinders for control of exhaust species

DOEpatents

Graves, Ronald L [Knoxville, TN; West, Brian H [Knoxville, TN; Huff, Shean P [Knoxville, TN; Parks, II, James E

2008-12-30

A method and system controls engine-out exhaust species of a combustion engine having a plurality of cylinders. The method typically includes various combinations of steps such as controlling combustion parameters in individual cylinders, grouping the individual cylinders into a lean set and a rich set of one or more cylinders, combusting the lean set in a lean combustion parameter condition having a lean air:fuel equivalence ratio, combusting the rich set in a rich combustion parameter condition having a rich air:fuel equivalence ratio, and adjusting the lean set and the rich set of one or more cylinders to generate net-lean combustion. The exhaust species may have elevated concentrations of hydrogen and oxygen.

Leadership requirements for Lean versus servant leadership in health care: a systematic review of the literature.

PubMed

Aij, Kjeld Harald; Rapsaniotis, Sofia

2017-01-01

As health care organizations face pressures to improve quality and efficiency while reducing costs, leaders are adopting management techniques and tools used in manufacturing and other industries, especially Lean. Successful Lean leaders appear to use a coaching leadership style that shares underlying principles with servant leadership. There is little information about specific similarities and differences between Lean and servant leaderships. We systematically reviewed the literature on Lean leadership, servant leadership, and health care and performed a comparative analysis of attributes using Russell and Stone's leadership framework. We found significant overlap between the two leadership styles, although there were notable differences in origins, philosophy, characteristics and behaviors, and tools. We conclude that both Lean and servant leaderships are promising models that can contribute to the delivery of patient-centered, high-value care. Servant leadership may provide the means to engage and develop employees to become successful Lean leaders in health care organizations.

Quality improvement in basic histotechnology: the lean approach.

PubMed

Clark, David

2016-01-01

Lean is a comprehensive system of management based on the Toyota production system (TPS), encompassing all the activities of an organization. It focuses management activity on creating value for the end-user by continuously improving operational effectiveness and removing waste. Lean management creates a culture of continuous quality improvement with a strong emphasis on developing the problem-solving capability of staff using the scientific method (Deming's Plan, Do, Check, Act cycle). Lean management systems have been adopted by a number of histopathology departments throughout the world to simultaneously improve quality (reducing errors and shortening turnround times) and lower costs (by increasing efficiency). This article describes the key concepts that make up a lean management system, and how these concepts have been adapted from manufacturing industry and applied to histopathology using a case study of lean implementation and evidence from the literature. It discusses the benefits, limitations, and pitfalls encountered when implementing lean management systems.

Using Simulation to Explore Lean Manufacturing Implementation Strategies

ERIC Educational Resources Information Center

Shannon, Patrick W.; Krumwiede, Kip R.; Street, Jeffrey N.

2010-01-01

Lean manufacturing, an outgrowth of the Toyota Production System, has spread far beyond the automobile industry and is seen by many leaders as a key management philosophy in the battle to compete on an international scale. Successful implementation of lean requires that managers and employees be educated in the proper application of lean tools and…

Teaching Special Decisions in a Lean Accounting Environment

ERIC Educational Resources Information Center

Haskin, Daniel

2010-01-01

Lean accounting has become increasingly important as more and more companies adopt the lean enterprise model or some variation of it. Cost and managerial accounting textbooks continue to use, almost exclusively, models based on standard overhead absorption, which if used in a lean environment will not accurately reflect the benefits from the…

Healthcare workers' perceptions of lean: a context-sensitive, mixed methods study in three Swedish hospitals.

PubMed

Holden, Richard J; Eriksson, Andrea; Andreasson, Jörgen; Williamsson, Anna; Dellve, Lotta

2015-03-01

As the application of lean in healthcare expands, further research is needed in at least two areas: first, on the role of context in shaping lean and its consequences and second, on how healthcare workers perceive lean. Accordingly, this context-sensitive, mixed methods study addressed how hospital workers' perceptions of lean varied across contexts in three Swedish hospitals. Registered nurses and physicians at the hospitals and across units differing in acuity completed standardized surveys (N = 236, 57% response rate) about their perceptions of hospital-wide lean implementation. Perceptions varied by: hospital context, with one hospital's employees reporting the least favorable perceptions; unit acuity, with higher-acuity units reporting more favorable perceptions; and professional role, with nurses reporting more favorable perceptions than physicians. Individual interviews, group interviews, and observations provided insight about these dissimilar contexts and possible explanations for context-specific variability. Findings are discussed with respect to strategies for implementing lean in healthcare; the importance of attending to levels, context, and worker consequences of lean; and directions for future research. Copyright © 2014 Elsevier Ltd and The Ergonomics Society. All rights reserved.

Healthcare workers' perceptions of lean: A context-sensitive, mixed methods study in three Swedish hospitals

PubMed Central

Holden, Richard J.; Eriksson, Andrea; Andreasson, Jörgen; Williamsson, Anna; Dellve, Lotta

2014-01-01

As the application of lean in healthcare expands, further research is needed in at least two areas: first, on the role of context in shaping lean and its consequences and second, on how healthcare workers perceive lean. Accordingly, this context-sensitive, mixed methods study addressed how hospital workers' perceptions of lean varied across contexts in three Swedish hospitals. Registered nurses and physicians at the hospitals and across units differing in acuity completed standardized surveys (N=236, 57% response rate) about their perceptions of hospital-wide lean implementation. Perceptions varied by: hospital context, with one hospital's employees reporting the least favorable perceptions; unit acuity, with higher-acuity units reporting more favorable perceptions; and professional role, with nurses reporting more favorable perceptions than physicians. Individual interviews, group interviews, and observations provided insight about these dissimilar contexts and possible explanations for context-specific variability. Findings are discussed with respect to strategies for implementing lean in healthcare; the importance of attending to levels, context, and worker consequences of lean; and directions for future research. PMID:25479987

Waste in health information systems: a systematic review.

PubMed

Awang Kalong, Nadia; Yusof, Maryati

2017-05-08

Purpose The purpose of this paper is to discuss a systematic review on waste identification related to health information systems (HIS) in Lean transformation. Design/methodology/approach A systematic review was conducted on 19 studies to evaluate Lean transformation and tools used to remove waste related to HIS in clinical settings. Findings Ten waste categories were identified, along with their relationships and applications of Lean tool types related to HIS. Different Lean tools were used at the early and final stages of Lean transformation; the tool selection depended on the waste characteristic. Nine studies reported a positive impact from Lean transformation in improving daily work processes. The selection of Lean tools should be made based on the timing, purpose and characteristics of waste to be removed. Research limitations/implications Overview of waste and its category within HIS and its analysis from socio-technical perspectives enabled the identification of its root cause in a holistic and rigorous manner. Practical implications Understanding waste types, their root cause and review of Lean tools could subsequently lead to the identification of mitigation approach to prevent future error occurrence. Originality/value Specific waste models for HIS settings are yet to be developed. Hence, the identification of the waste categories could guide future implementation of Lean transformations in HIS settings.

Readiness factors for lean implementation in healthcare settings--a literature review.

PubMed

Al-Balushi, S; Sohal, A S; Singh, P J; Al Hajri, A; Al Farsi, Y M; Al Abri, R

2014-01-01

The purpose of this paper is to determine the readiness factors that are critical to the application and success of lean operating principles in healthcare organizations through a review of relevant literature. A comprehensive review of literature focussing on lean and lean healthcare was conducted. Leadership, organizational culture, communication, training, measurement, and reward systems are all commonly attributed readiness factors throughout general change management and lean literature. However, directly related to the successful implementation of lean in healthcare is that a setting is able to authorize a decentralized management style and undertake an end-to-end process view. These can be particularly difficult initiatives for complex organizations such as healthcare settings. The readiness factors identified are based on a review of the published literature. The external validity of the findings could be enhanced if tested using an empirical study. The readiness factors identified will enable healthcare practitioners to be better prepared as they begin their lean journeys. Sustainability of the lean initiative will be at stake if these readiness factors are not addressed. To the best of the knowledge, this is the first paper that provides a consolidated list of key lean readiness factors that can guide practice, as well as future theory and empirical research.

Does lean muddy the quality improvement waters? A qualitative study of how a hospital management team understands lean in the context of quality improvement.

PubMed

Savage, Carl; Parke, Louise; von Knorring, Mia; Mazzocato, Pamela

2016-10-19

Health care has experimented with many different quality improvement (QI) approaches with greater variation in name than content. This has been dubbed pseudoinnovation. However, it could also be that the subtleties and differences are not clearly understood. To explore this further, the purpose of this study was to explore how hospital managers perceive lean in the context of QI. We used a qualitative study design with semi-structured interviews to explore twelve top managers' perceptions of the relationship between lean and quality improvement (QI) at a university-affiliated hospital. Managers described that QI and lean shared the same overall purpose: focus on patient needs and improve efficiency and effectiveness. Employee involvement was emphasized in both strategies, as well as the support offered by managers of staff initiatives. QI was perceived as a strategy that could support structural changes at the organizational level whereas lean was seen as applicable at the operational level. Moreover, lean carried a negative connotation, lacked the credibility of QI, and was perceived as a management fad. Aspects of QI and lean were misunderstood. In a context where lean remains an abstract term, and staff associate lean with automotive applications and cost reduction, it may be fruitful for managers to invest time and resources to develop a strategy for continual improvement and utilize vocabulary that resonates with health care staff. This could reduce the risk that improvement efforts are rejected out of hand.

Incorporation of lean methodology into pharmacy residency programs.

PubMed

John, Natalie; Snider, Holly; Edgerton, Lisa; Whalin, Laurie

2017-03-15

The implementation of lean methodology into pharmacy residency programs at a community teaching hospital is described. New Hanover Regional Medical Center, a community teaching hospital in southeastern North Carolina, fully adopted a lean culture in 2010. Given the success of lean strategies organizationally, this methodology was used to assist with the evaluation and development of its pharmacy residency programs in 2014. Lean tools and activities have also been incorporated into residency requirements and rotation learning activities. The majority of lean events correspond to the required competency areas evaluating leadership and management, teaching, and education. These events have included participation in and facilitation of various lean problem-solving and communication tools. The application of the 4 rules of lean has resulted in enhanced management of the programs and provides a set of tools by which continual quality improvement can be ensured. Regular communication and direct involvement of all invested parties have been critical in developing and sustaining new improvements. In addition to program enhancements, lean methodology offers novel methods by which residents may be incorporated into leadership activities. The incorporation of lean methodology into pharmacy residency programs has translated into a variety of realized and potential benefits for the programs, the preceptors and residents, and the health system. Specific areas of growth have included quality-improvement processes, the expansion of leadership opportunities for residents, and improved communication among program directors, preceptors, and residents. Copyright © 2017 by the American Society of Health-System Pharmacists, Inc. All rights reserved.

Estimation of lean and fat composition of pork ham using image processing measurements

NASA Astrophysics Data System (ADS)

Jia, Jiancheng; Schinckel, Allan P.; Forrest, John C.

1995-01-01

This paper presents a method of estimating the lean and fat composition in pork ham from cross-sectional area measurements using image processing technology. The relationship between the quantity of ham lean and fat mass with the ham lean and fat areas was studied. The prediction equations for pork ham composition based on the ham cross-sectional area measurements were developed. The results show that ham lean weight was related to the ham lean area (r equals .75, P < .0001) while ham fat weight was related tot the ham fat area (r equals .79, P equals .0001). Ham lean weight was highly related to the product of ham total weight times percentage ham lean area (r equals .96, P < .0001). Ham fat weight was highly related to the product of ham total weight times percentage ham fat area (r equals .88, P < .0001). The best combination of independent variables for estimating ham lean weight was trimmed wholesale ham weight and percentage ham fat area with a coefficient of determination of 92%. The best combination of independent variables for estimating ham fat weight was trimmed wholesale ham weight and percentage ham fat area with a coefficient of determination of 78%. Prediction equations with either two or three independent variables did not significantly increase the accuracy of prediction. The results of this study indicate that the weight of ham lean and fat could be predicted from ham cross-sectional area measurements using image analysis in combination with wholesale ham weight.

Increased Coagulation and Decreased Fibrinolysis as Measured with Overall Hemostatic Potential Are Dependent on BMI and Not Associated with PCOS.

PubMed

Rakusa, Matej; Jensterle, Mojca; Božič-Mijovski, Mojca; Janez, Andrej

2017-05-01

Overall hemostatic potential (OHP) captures all factors that affect coagulation and fibrinolysis cascade. It has not yet been assessed in polycystic ovary syndrome (PCOS). The aim of the study was to identify the relationship of OHP with a syndrome per se and body mass index (BMI). In 90 women with PCOS aged 30.9 ± 8.1 years (50 obese, 13 overweight, and 27 lean) and 21 healthy age-matched controls (11 obese and 10 lean), OHP with overall coagulation potential (OCP) and overall fibrinolytic potential (OFP) was determined spectrophotometrically. OFP was calculated. OHP increased with BMI in PCOS (9.6 ± 2.3 in lean, 12.5 ± 5.1 in overweight, and 15.5 ± 3.8 Abs-sum in obese) and in controls (9.1 ± 1.0 in lean and 17.3 ± 4.6 Abs-sum in obese). There was significant difference between lean and obese PCOS (P < 0.001) and between lean and obese controls (P < 0.001). OCP also increased with BMI in PCOS (P < 0.001 for lean vs. obese) and in controls (P < 0.001 for lean vs. obese). OFP decreased with BMI in PCOS (P < 0.001 for obese vs. overweight vs. lean) and in controls (P < 0.001 for obese vs. lean). OHP in healthy obese and obese PCOS did not differ significantly, while OHP for healthy obese was increased in comparison to overweight and lean PCOS (P < 0.001). PCOS was not associated with increased OHP compared with BMI and age-matched controls. However, increase in OHP was positively associated with BMI in PCOS and healthy women.

Validation of a skinfold based index for tracking proportional changes in lean mass

PubMed Central

Slater, G J; Duthie, G M; Pyne, D B; Hopkins, W G

2006-01-01

Background The lean mass index (LMI) is a new empirical measure that tracks within‐subject proportional changes in body mass adjusted for changes in skinfold thickness. Objective To compare the ability of the LMI and other skinfold derived measures of lean mass to monitor changes in lean mass. Methods 20 elite rugby union players undertook full anthropometric profiles on two occasions 10 weeks apart to calculate the LMI and five skinfold based measures of lean mass. Hydrodensitometry, deuterium dilution, and dual energy x ray absorptiometry provided a criterion choice, four compartment (4C) measure of lean mass for validation purposes. Regression based measures of validity, derived for within‐subject proportional changes through log transformation, included correlation coefficients and standard errors of the estimate. Results The correlation between change scores for the LMI and 4C lean mass was moderate (0.37, 90% confidence interval −0.01 to 0.66) and similar to the correlations for the other practical measures of lean mass (range 0.26 to 0.42). Standard errors of the estimate for the practical measures were in the range of 2.8–2.9%. The LMI correctly identified the direction of change in 4C lean mass for 14 of the 20 athletes, compared with 11 to 13 for the other practical measures of lean mass. Conclusions The LMI is probably as good as other skinfold based measures for tracking lean mass and is theoretically more appropriate. Given the impracticality of the 4C criterion measure for routine field use, the LMI may offer a convenient alternative for monitoring physique changes, provided its utility is established under various conditions. PMID:16505075

Guiding inpatient quality improvement: a systematic review of Lean and Six Sigma.

PubMed

Glasgow, Justin M; Scott-Caziewell, Jill R; Kaboli, Peter J

2010-12-01

Two popular quality improvement (QI) approaches in health care are Lean and Six Sigma. Hospitals continue to adopt these QI approaches-or the hybrid Lean Sigma approach-with little knowledge on how well they produce sustainable improvements. A systematic literature review was conducted to determine whether Lean, Six Sigma, or Lean Sigma have been effectively used to create and sustain improvements in the acute care setting. Databases were searched for articles published in the health care, business, and engineering literatures. Study inclusion criteria required identification of a Six Sigma, Lean, or Lean Sigma project; QI efforts focused on hospitalized patients; descriptions of project improvements; and reported results. Depending on the quality of data reported, articles were classified as summary reports, pre-post observational studies, or time-series reports. Database searches identified 539 potential articles. After review of titles, abstracts, and full text, 47 articles met inclusion criteria--10 articles summarized multiple projects, 12 reported Lean projects, 20 reported Six Sigma projects, and 5 reported Lean Sigma projects. Generally, the studies provided limited data, with only 15 articles providing any sort of follow-up data; of the 15, only 3 report a follow-up period greater than two years. Lean, Six Sigma, and Lean Sigma as QI approaches can aid institutions in tackling a wide variety of problems encountered in acute care. However, the true impact of these approaches is difficult to judge, given that the lack of rigorous evaluation or clearly sustained improvements provides little evidence supporting broad adoption. There is still a need for future work that will improve the evidence base for understanding more about QI approaches and how to achieve sustainable improvement.

Lean thinking in hospitals: is there a cure for the absence of evidence? A systematic review of reviews

PubMed Central

Andersen, Hege; Røvik, Kjell Arne; Ingebrigtsen, Tor

2014-01-01

Objective Lean interventions aim to improve quality of healthcare by reducing waste and facilitate flow in work processes. There is conflicting evidence on the outcomes of lean thinking, with quantitative and qualitative studies often contradicting each other. We suggest that reviewing the literature within the approach of a new contextual framework can deepen our understanding of lean as a quality-improvement method. This article theorises the concept of context by establishing a two-dimensional conceptual framework acknowledging lean as complex social interventions, deployed in different organisational dimensions and domains. The specific aim of the study was to identify factors facilitating intended outcomes from lean interventions, and to understand when and how different facilitators contribute. Design A two-dimensional conceptual framework was developed by combining Shortell's Dimensions of capability with Walshes’ Domains of an intervention. We then conducted a systematic review of lean review articles concerning hospitals, published in the period 2000–2012. The identified lean facilitators were categorised according to the intervention domains and dimensions of capability provided by the framework. Results We provide a framework emphasising context by relating facilitators to domains and dimensions of capability. 23 factors enabling a successful lean intervention in hospitals were identified in the systematic review, where management and a supportive culture, training, accurate data, physicians and team involvement were most frequent. Conclusions In the absence of evidence, the two-dimensional framework, incorporating the context, may prove useful for future research on variation in outcomes from lean interventions. Findings from the review suggest that characteristics and local application of lean, in addition to strategic and cultural capability, should be given further attention in healthcare quality improvement. PMID:24435890

Physical activity modifies the association between dietary protein and lean mass of postmenopausal women

PubMed Central

Martinez, Jessica A.; Wertheim, Betsy C.; Thomson, Cynthia A.; Bea, Jennifer W.; Wallace, Robert; Allison, Matthew; Snetselaa, Linda; Chen, Zhao; Nassir, Rami; Thompson, Patricia A.

2016-01-01

Background Maintenance of lean muscle mass and related strength is associated with lower risk for numerous chronic diseases of aging in women. Objective To evaluate whether the association between dietary protein and lean mass differs by physical activity level, amino acid composition, and body mass index categories. Design Cross-sectional analysis of a prospective cohort. Participants/setting Postmenopausal women from the Women’s Health Initiative with body composition measurements by dual-energy X-ray absorptiometry (n=8,298). Main outcome measures Percent lean mass, percent fat mass and lean body mass index. Statistical analyses performed Linear regression models adjusted for scanner serial number, age, calibrated energy intake, race/ethnicity, neighborhood socioeconomic status, and recreational physical activity were used to determine the relationship between protein intake and body composition measures. Likelihood ratio tests and stratified analysis were used to investigate physical activity and body mass index as potential effect modifiers. Results Biomarker-calibrated protein intake was positively associated with percent lean mass; women in the highest protein quintile had 6.3 percentage points higher lean mass than the lowest quintile (P < 0.001). This difference rose to 8.5 percentage points for physically active women in the highest protein quintile (Pinteraction = 0.023). Percent fat mass and lean body mass index were both inversely related to protein intake (both P < 0.001). Physical activity further reduced percent fat mass (Pinteraction = 0.022) and lean body mass index (Pinteraction = 0.011). Leucine intake was associated with lean mass, as were branched chain amino acids combined (both P < 0.001), but not independent of total protein. All associations were observed for normal-weight, overweight, and obese women. Conclusions Protein consumption up to 2.02 g/kg body weight daily is positively associated with lean mass in postmenopausal women. Importantly, those that also engage in physical activity have the highest lean mass across body mass index categories. PMID:27914915

Cardiovascular and metabolic responses to fasting and thermoneutrality are conserved in obese Zucker rats.

PubMed

Overton, J M; Williams, T D; Chambers, J B; Rashotte, M E

2001-04-01

The primary purpose of the study was to test the hypothesis that reduced leptin signaling is necessary to elicit the cardiovascular and metabolic responses to fasting. Lean (Fa/?; normal leptin receptor; n = 7) and obese (fa/fa; mutated leptin receptor; n = 8) Zucker rats were instrumented with telemetry transmitters and housed in metabolic chambers at 23 degrees C (12:12-h light-dark cycle) for continuous (24 h) measurement of metabolic and cardiovascular variables. Before fasting, mean arterial pressure (MAP) was higher (MAP: obese = 103 +/- 3; lean = 94 +/- 1 mmHg), whereas oxygen consumption (VO(2): obese = 16.5 +/- 0.3; lean = 18.6 +/- 0.2 ml. min(-1). kg(-0.75)) was lower in obese Zucker rats compared with their lean controls. Two days of fasting had no effect on MAP in either lean or obese Zucker rats, whereas VO(2) (obese = -3.1 +/- 0.3; lean = -2.9 +/- 0.1 ml. min(-1). kg(-0.75)) and heart rate (HR: obese = -56 +/- 4; lean = -42 +/- 4 beats/min) were decreased markedly in both groups. Fasting increased HR variability both in lean (+1.8 +/- 0.4 ms) and obese (+2.6 +/- 0.3 ms) Zucker rats. After a 6-day period of ad libitum refeeding, when all parameters had returned to near baseline levels, the cardiovascular and metabolic responses to 2 days of thermoneutrality (ambient temperature 29 degrees C) were determined. Thermoneutrality reduced VO(2) (obese = -2.4 +/- 0.2; lean = -3.3 +/- 0.2 ml. min(-1). kg(-0.75)), HR (obese = -46 +/- 5; lean = -55 +/- 4 beats/min), and MAP (obese = -13 +/- 6; lean = -10 +/- 1 mmHg) similarly in lean and obese Zucker rats. The results indicate that the cardiovascular and metabolic responses to fasting and thermoneutrality are conserved in Zucker rats and suggest that intact leptin signaling may not be requisite for the metabolic and cardiovascular responses to reduced energy intake.

Filter-based control of particulate matter from a lean gasoline direct injection engine

DOE Office of Scientific and Technical Information (OSTI.GOV)

Parks, II, James E; Lewis Sr, Samuel Arthur; DeBusk, Melanie Moses

New regulations requiring increases in vehicle fuel economy are challenging automotive manufacturers to identify fuel-efficient engines for future vehicles. Lean gasoline direct injection (GDI) engines offer significant increases in fuel efficiency over the more common stoichiometric GDI engines already in the marketplace. However, particulate matter (PM) emissions from lean GDI engines, particularly during stratified combustion modes, are problematic for lean GDI technology to meet U.S. Environmental Protection Agency Tier 3 and other future emission regulations. As such, the control of lean GDI PM with wall-flow filters, referred to as gasoline particulate filter (GPF) technology, is of interest. Since lean GDImore » PM chemistry and morphology differ from diesel PM (where more filtration experience exists), the functionality of GPFs needs to be studied to determine the operating conditions suitable for efficient PM removal. In addition, lean GDI engine exhaust temperatures are generally higher than diesel engines which results in more continuous regeneration of the GPF and less presence of the soot cake layer common to diesel particulate filters. Since the soot layer improves filtration efficiency, this distinction is important to consider. Research on the emission control of PM from a lean GDI engine with a GPF was conducted on an engine dynamometer. PM, after dilution, was characterized with membrane filters, organic vs. elemental carbon characterization, and size distribution techniques at various steady state engine speed and load points. The engine was operated in three primary combustion modes: stoichiometric, lean homogeneous, and lean stratified. In addition, rich combustion was utilized to simulate PM from engine operation during active regeneration of lean NOx control technologies. High (>95%) PM filtration efficiencies were observed over a wide range of conditions; however, some PM was observed to slip through the GPF at high speed and load conditions. The PM characterization at various engine speeds and loads will help enable optimized GPF design and control to achieve more fuel efficient lean GDI vehicles with low PM emissions.« less

The Finnish healthcare services lean management.

PubMed

Hihnala, Susanna; Kettunen, Lilja; Suhonen, Marjo; Tiirinki, Hanna

2018-02-05

Purpose The purpose of this paper is to discuss health services managers' experiences of management in a special health-care unit and development efforts from the point of view of the Lean method. Additionally, the aim is to deepen the knowledge of the managers' work and nature of the Lean method development processes in the workplace. The research focuses on those aspects and results of Lean method that are currently being used in health-care environments. Design/methodology/approach These data were collected through a number of thematic interviews. The participants were nurse managers ( n = 7) and medical managers ( n = 7) who applied Lean management in their work at the University Hospital in the Northern Ostrobothnia Health Care District. The data were analysed with a qualitative content analysis. Findings A common set of values in specialized health-care services, development of activities and challenges for management in the use of the Lean manager development model to improve personal management skills. Practical implications Managers in specialized health-care services can develop and systematically manage with the help of the Lean method. This emphasizes assumptions, from the point of view of management, about systems development when the organization uses the Lean method. The research outcomes originate from specialized health-care settings in Finland in which the Lean method and its associated management principles have been implemented and applied to the delivery of health care. Originality/value The study shows that the research results and in-depth knowledge on Lean method principles can be applied to health-care management and development processes. The research also describes health services managers' experiences of using the Lean method. In the future, these results can be used to improve Lean management skills, identify personal professional competencies and develop skills required in development processes. Also, the research findings can be used in the training of health services managers in the health-care industry worldwide and to help them survive the pressure to change repeatedly.

Physical Activity Modifies the Association between Dietary Protein and Lean Mass of Postmenopausal Women.

PubMed

Martinez, Jessica A; Wertheim, Betsy C; Thomson, Cynthia A; Bea, Jennifer W; Wallace, Robert; Allison, Matthew; Snetselaar, Linda; Chen, Zhao; Nassir, Rami; Thompson, Patricia A

2017-02-01

Maintenance of lean muscle mass and related strength is associated with lower risk for numerous chronic diseases of aging in women. Our aim was to evaluate whether the association between dietary protein and lean mass differs by physical activity level, amino acid composition, and body mass index categories. We performed a cross-sectional analysis of a prospective cohort. Participants were postmenopausal women from the Women's Health Initiative with body composition measurements by dual-energy x-ray absorptiometry (n=8,298). Our study measured percent lean mass, percent fat mass, and lean body mass index. Linear regression models adjusted for scanner serial number, age, calibrated energy intake, race/ethnicity, neighborhood socioeconomic status, and recreational physical activity were used to determine the relationship between protein intake and body composition measures. Likelihood ratio tests and stratified analysis were used to investigate physical activity and body mass index as potential effect modifiers. Biomarker-calibrated protein intake was positively associated with percent lean mass; women in the highest protein quintile had 6.3 percentage points higher lean mass than the lowest quintile (P<0.001). This difference rose to 8.5 percentage points for physically active women in the highest protein quintile (P interaction =0.023). Percent fat mass and lean body mass index were both inversely related to protein intake (both P<0.001). Physical activity further reduced percent fat mass (P interaction =0.022) and lean body mass index (P interaction =0.011). Leucine intake was associated with lean mass, as were branched chain amino acids combined (both P<0.001), but not independent of total protein. All associations were observed for normal-weight, overweight, and obese women. Protein consumption up to 2.02 g/kg body weight daily is positively associated with lean mass in postmenopausal women. Importantly, those that also engage in physical activity have the highest lean mass across body mass index categories. Copyright © 2017 Academy of Nutrition and Dietetics. Published by Elsevier Inc. All rights reserved.

How does lean work in emergency care? A case study of a lean-inspired intervention at the Astrid Lindgren Children's hospital, Stockholm, Sweden

PubMed Central

2012-01-01

Background There is growing interest in applying lean thinking in healthcare, yet, there is still limited knowledge of how and why lean interventions succeed (or fail). To address this gap, this in-depth case study examines a lean-inspired intervention in a Swedish pediatric Accident and Emergency department. Methods We used a mixed methods explanatory single case study design. Hospital performance data were analyzed using analysis of variance (ANOVA) and statistical process control techniques to assess changes in performance one year before and two years after the intervention. We collected qualitative data through non-participant observations, semi-structured interviews, and internal documents to describe the process and content of the lean intervention. We then analyzed empirical findings using four theoretical lean principles (Spear and Bowen 1999) to understand how and why the intervention worked in its local context as well as to identify its strengths and weaknesses. Results Improvements in waiting and lead times (19-24%) were achieved and sustained in the two years following lean-inspired changes to employee roles, staffing and scheduling, communication and coordination, expertise, workspace layout, and problem solving. These changes resulted in improvement because they: (a) standardized work and reduced ambiguity, (b) connected people who were dependent on one another, (c) enhanced seamless, uninterrupted flow through the process, and (d) empowered staff to investigate problems and to develop countermeasures using a "scientific method". Contextual factors that may explain why not even greater improvement was achieved included: a mismatch between job tasks, licensing constraints, and competence; a perception of being monitored, and discomfort with inter-professional collaboration. Conclusions Drawing on Spear and Bowen's theoretical propositions, this study explains how a package of lean-like changes translated into better care process management. It adds new knowledge regarding how lean principles can be beneficially applied in healthcare and identifies changes to professional roles as a potential challenge when introducing lean thinking there. This knowledge may enable health care organizations and managers in other settings to configure their own lean program and to better understand the reasons behind lean's success (or failure). PMID:22296919

How does lean work in emergency care? A case study of a lean-inspired intervention at the Astrid Lindgren Children's hospital, Stockholm, Sweden.

PubMed

Mazzocato, Pamela; Holden, Richard J; Brommels, Mats; Aronsson, Håkan; Bäckman, Ulrika; Elg, Mattias; Thor, Johan

2012-02-01

There is growing interest in applying lean thinking in healthcare, yet, there is still limited knowledge of how and why lean interventions succeed (or fail). To address this gap, this in-depth case study examines a lean-inspired intervention in a Swedish pediatric Accident and Emergency department. We used a mixed methods explanatory single case study design. Hospital performance data were analyzed using analysis of variance (ANOVA) and statistical process control techniques to assess changes in performance one year before and two years after the intervention. We collected qualitative data through non-participant observations, semi-structured interviews, and internal documents to describe the process and content of the lean intervention. We then analyzed empirical findings using four theoretical lean principles (Spear and Bowen 1999) to understand how and why the intervention worked in its local context as well as to identify its strengths and weaknesses. Improvements in waiting and lead times (19-24%) were achieved and sustained in the two years following lean-inspired changes to employee roles, staffing and scheduling, communication and coordination, expertise, workspace layout, and problem solving. These changes resulted in improvement because they: (a) standardized work and reduced ambiguity, (b) connected people who were dependent on one another, (c) enhanced seamless, uninterrupted flow through the process, and (d) empowered staff to investigate problems and to develop countermeasures using a "scientific method". Contextual factors that may explain why not even greater improvement was achieved included: a mismatch between job tasks, licensing constraints, and competence; a perception of being monitored, and discomfort with inter-professional collaboration. Drawing on Spear and Bowen's theoretical propositions, this study explains how a package of lean-like changes translated into better care process management. It adds new knowledge regarding how lean principles can be beneficially applied in healthcare and identifies changes to professional roles as a potential challenge when introducing lean thinking there. This knowledge may enable health care organizations and managers in other settings to configure their own lean program and to better understand the reasons behind lean's success (or failure).

Birth weight and growth from infancy to late adolescence in relation to fat and lean mass in early old age: findings from the MRC National Survey of Health and Development.

PubMed

Bann, D; Wills, A; Cooper, R; Hardy, R; Aihie Sayer, A; Adams, J; Kuh, D

2014-01-01

High birth weight and greater weight gain in infancy have been associated with increased risk of obesity as assessed using body mass index, but few studies have examined associations with direct measures of fat and lean mass. This study examined associations of birth weight and weight and height gain in infancy, childhood and adolescence with fat and lean mass in early old age. A total of 746 men and 812 women in England, Scotland and Wales from the MRC National Survey of Health and Development whose heights and weights had been prospectively ascertained across childhood and adolescence and who had dual energy X-ray absorptiometry measures at age 60-64 years. Associations of birth weight and standardised weight and height (0-2 (weight only), 2-4, 4-7, 7-11, 11-15, 15-20 years) gain velocities with outcome measures were examined. Higher birth weight was associated with higher lean mass and lower android/gynoid ratio at age 60-64 years. For example, the mean difference in lean mass per 1 standard deviation increase in birth weight was 1.54 kg in males (95% confidence interval=1.04, 2.03) and 0.78 kg in females (0.41, 1.14). Greater weight gain in infancy was associated with higher lean mass, whereas greater gains in weight in later childhood and adolescence were associated with higher fat and lean mass, and fat/lean and android/gynoid ratios. Across growth intervals greater height gain was associated with higher lean but not fat mass, and with lower fat/lean and android/gynoid ratios. Findings suggest that growth in early life may have lasting effects on fat and lean mass. Greater weight gain before birth and in infancy may be beneficial by leading to higher lean mass, whereas greater weight gain in later childhood and adolescence may be detrimental by leading to higher fat/lean and android/gynoid ratios.

Optimizing clinical operations as part of a global emergency medicine initiative in Kumasi, Ghana: application of Lean manufacturing principals to low-resource health systems.

PubMed

Carter, Patrick M; Desmond, Jeffery S; Akanbobnaab, Christopher; Oteng, Rockefeller A; Rominski, Sarah D; Barsan, William G; Cunningham, Rebecca M

2012-03-01

Although many global health programs focus on providing clinical care or medical education, improving clinical operations can have a significant effect on patient care delivery, especially in developing health systems without high-level operations management. Lean manufacturing techniques have been effective in decreasing emergency department (ED) length of stay, patient waiting times, numbers of patients leaving without being seen, and door-to-balloon times for ST-elevation myocardial infarction in developed health systems, but use of Lean in low to middle income countries with developing emergency medicine (EM) systems has not been well characterized. To describe the application of Lean manufacturing techniques to improve clinical operations at Komfo Anokye Teaching Hospital (KATH) in Ghana and to identify key lessons learned to aid future global EM initiatives. A 3-week Lean improvement program focused on the hospital admissions process at KATH was completed by a 14-person team in six stages: problem definition, scope of project planning, value stream mapping, root cause analysis, future state planning, and implementation planning. The authors identified eight lessons learned during our use of Lean to optimize the operations of an ED in a global health setting: 1) the Lean process aided in building a partnership with Ghanaian colleagues; 2) obtaining and maintaining senior institutional support is necessary and challenging; 3) addressing power differences among the team to obtain feedback from all team members is critical to successful Lean analysis; 4) choosing a manageable initial project is critical to influence long-term Lean use in a new environment; 5) data intensive Lean tools can be adapted and are effective in a less resourced health system; 6) several Lean tools focused on team problem-solving techniques worked well in a low-resource system without modification; 7) using Lean highlighted that important changes do not require an influx of resources; and 8) despite different levels of resources, root causes of system inefficiencies are often similar across health care systems, but require unique solutions appropriate to the clinical setting. Lean manufacturing techniques can be successfully adapted for use in developing health systems. Lessons learned from this Lean project will aid future introduction of advanced operations management techniques in low- to middle-income countries. © 2012 by the Society for Academic Emergency Medicine.

Interactions between lean management and the psychosocial work environment in a hospital setting - a multi-method study.

PubMed

Ulhassan, Waqar; von Thiele Schwarz, Ulrica; Thor, Johan; Westerlund, Hugo

2014-10-22

As health care struggles to meet increasing demands with limited resources, Lean has become a popular management approach. It has mainly been studied in relation to health care performance. The empirical evidence as to how Lean affects the psychosocial work environment has been contradictory. This study aims to study the interaction between Lean and the psychosocial work environment using a comprehensive model that takes Lean implementation information, as well as Lean theory and the particular context into consideration. The psychosocial work environment was measured twice with the Copenhagen Psychosocial Questionnaire (COPSOQ) employee survey during Lean implementations on May-June 2010 (T1) (n = 129) and November-December 2011 (T2) (n = 131) at three units (an Emergency Department (ED), Ward-I and Ward-II). Information based on qualitative data analysis of the Lean implementations and context from a previous paper was used to predict expected change patterns in the psychosocial work environment from T1 to T2 and subsequently compared with COPSOQ-data through linear regression analysis. Between T1 and T2, qualitative information showed a well-organized and steady Lean implementation on Ward-I with active employee participation, a partial Lean implementation on Ward-II with employees not seeing a clear need for such an intervention, and deterioration in already implemented Lean activities at ED, due to the declining interest of top management. Quantitative data analysis showed a significant relation between the expected and actual results regarding changes in the psychosocial work environment. Ward-I showed major improvements especially related to job control and social support, ED showed a major decline with some exceptions while Ward-II also showed improvements similar to Ward-I. The results suggest that Lean may have a positive impact on the psychosocial work environment given that it is properly implemented. Also, the psychosocial work environment may even deteriorate if Lean work deteriorates after implementation. Employee managers and researchers should note the importance of employee involvement in the change process. Employee involvement may minimize the intervention's harmful effects on psychosocial work factors. We also found that a multi-method may be suitable for investigating relations between Lean and the psychosocial work environment.

Optimizing Clinical Operations as part of a Global Emergency Medicine Initiative in Kumasi, Ghana: Application of Lean Manufacturing Principals to Low Resource Health Systems

PubMed Central

Carter, Patrick M.; Desmond, Jeffery S.; Akanbobnaab, Christopher; Oteng, Rockefeller A.; Rominski, Sarah; Barsan, William G.; Cunningham, Rebecca

2012-01-01

Background Although many global health programs focus on providing clinical care or medical education, improving clinical operations can have a significant effect on patient care delivery, especially in developing health systems without high-level operations management. Lean manufacturing techniques have been effective in decreasing emergency department (ED) length of stay, patient waiting times, numbers of patients leaving without being seen, and door-to-balloon times for ST-elevation myocardial infarction in developed health systems; but use of Lean in low to middle income countries with developing emergency medicine systems has not been well characterized. Objectives To describe the application of Lean manufacturing techniques to improve clinical operations at Komfo Anokye Teaching Hospital in Ghana and to identify key lessons learned to aid future global EM initiatives. Methods A three-week Lean improvement program focused on the hospital admissions process at Komfo Anokye Teaching Hospital was completed by a 14-person team in six stages: problem definition, scope of project planning, value stream mapping, root cause analysis, future state planning, and implementation planning. Results The authors identified eight lessons learned during our use of Lean to optimize the operations of an ED in a global health setting: 1) the Lean process aided in building a partnership with Ghanaian colleagues; 2) obtaining and maintaining senior institutional support is necessary and challenging; 3) addressing power differences among the team to obtain feedback from all team members is critical to successful Lean analysis; 4) choosing a manageable initial project is critical to influence long-term Lean use in a new environment; 5) data intensive Lean tools can be adapted and are effective in a less resourced health system; 6) several Lean tools focused on team problem solving techniques worked well in a low resource system without modification; 7) using Lean highlighted that important changes do not require an influx of resources; 8) despite different levels of resources, root causes of system inefficiencies are often similar across health care systems, but require unique solutions appropriate to the clinical setting. Conclusions Lean manufacturing techniques can be successfully adapted for use in developing health systems. Lessons learned from this Lean project will aid future introduction of advanced operations management techniques in low to middle income countries. PMID:22435868

Obesity resistant mechanisms in the Lean polygenic mouse model as indicated by liver transcriptome and expression of selected genes in skeletal muscle

PubMed Central

2011-01-01

Background Divergently selected Lean and Fat mouse lines represent unique models for a polygenic form of resistance and susceptibility to obesity development. Previous research on these lines focused mainly on obesity-susceptible factors in the Fat line. This study aimed to examine the molecular basis of obesity-resistant mechanisms in the Lean line by analyzing various fat depots and organs, the liver transcriptome of selected metabolic pathways, plasma and lipid homeostasis and expression of selected skeletal muscle genes. Results Expression profiling using our custom Steroltalk v2 microarray demonstrated that Lean mice exhibit a higher hepatic expression of cholesterol biosynthesis genes compared to the Fat line, although this was not reflected in elevation of total plasma or liver cholesterol. However, FPLC analysis showed that protective HDL cholesterol was elevated in Lean mice. A significant difference between the strains was also found in bile acid metabolism. Lean mice had a higher expression of Cyp8b1, a regulatory enzyme of bile acid synthesis, and the Abcb11 bile acid transporter gene responsible for export of acids to the bile. Additionally, a higher content of blood circulating bile acids was observed in Lean mice. Elevated HDL and upregulation of some bile acids synthesis and transport genes suggests enhanced reverse cholesterol transport in the Lean line - the flux of cholesterol out of the body is higher which is compensated by upregulation of endogenous cholesterol biosynthesis. Increased skeletal muscle Il6 and Dio2 mRNA levels as well as increased activity of muscle succinic acid dehydrogenase (SDH) in the Lean mice demonstrates for the first time that changes in muscle energy metabolism play important role in the Lean line phenotype determination and corroborate our previous findings of increased physical activity and thermogenesis in this line. Finally, differential expression of Abcb11 and Dio2 identifies novel strong positional candidate genes as they map within the quantitative trait loci (QTL) regions detected previously in crosses between the Lean and Fat mice. Conclusion We identified novel candidate molecular targets and metabolic changes which can at least in part explain resistance to obesity development in the Lean line. The major difference between the Lean and Fat mice was in increased liver cholesterol biosynthesis gene mRNA expression, bile acid metabolism and changes in selected muscle genes' expression in the Lean line. The liver Abcb11 and muscle Dio2 were identified as novel positional candidate genes to explain part of the phenotypic difference between the Lean and Fat lines. PMID:21291556

Using Dynamic Value Stream Mapping and Lean Accounting Box Scores to Support Lean Implementation

ERIC Educational Resources Information Center

Woehrle, Stephen L.; Abou-Shady, Louay

2010-01-01

Lean has proven to be an effective management philosophy for improving businesses in a competitive market by eliminating waste and improving operations. An impact of implementing lean projects is the rapid reduction in inventory levels, which gives management the false impression that profits are decreasing while workers on the shop floor observe…

Building Lean Supply Chain and Manufacturing Skills through an Interactive Case Study

ERIC Educational Resources Information Center

Ozelkan, Ertunga C.; Teng, S. Gary; Johnson, Thomas; Benson, Tom; Nestvogel, Dean

2007-01-01

With the ongoing global pressure to cut costs and focus on quality, many companies have been implementing "lean manufacturing" concepts to survive in the competitive marketplace. Thus it is imperative that engineering and business graduates are equipped with the lean principles, and are ready to take ownership of lean initiatives as they enter the…

Comparison of the gut microbial community between obese and lean peoples using 16S gene sequencing in a Japanese population.

PubMed

Andoh, Akira; Nishida, Atsushi; Takahashi, Kenichiro; Inatomi, Osamu; Imaeda, Hirotsugu; Bamba, Shigeki; Kito, Katsuyuki; Sugimoto, Mitsushige; Kobayashi, Toshio

2016-07-01

Altered gut microbial ecology contributes to the development of metabolic diseases including obesity. In this study, we performed 16S rRNA sequence analysis of the gut microbiota profiles of obese and lean Japanese populations. The V3-V4 hypervariable regions of 16S rRNA of fecal samples from 10 obese and 10 lean volunteers were sequenced using the Illumina MiSeq(TM)II system. The average body mass index of the obese and lean group were 38.1 and 16.6 kg/m(2), respectively (p<0.01). The Shannon diversity index was significantly higher in the lean group than in the obese group (p<0.01). The phyla Firmicutes and Fusobacteria were significantly more abundant in obese people than in lean people. The abundance of the phylum Bacteroidetes and the Bacteroidetes/Firmicutes ratio were not different between the obese and lean groups. The genera Alistipes, Anaerococcus, Corpococcus, Fusobacterium and Parvimonas increased significantly in obese people, and the genera Bacteroides, Desulfovibrio, Faecalibacterium, Lachnoanaerobaculum and Olsenella increased significantly in lean people. Bacteria species possessing anti-inflammatory properties, such as Faecalibacterium prausnitzii, increased significantly in lean people, but bacteria species possessing pro-inflammatory properties increased in obese people. Obesity-associated gut microbiota in the Japanese population was different from that in Western people.

Lean Six Sigma implementation and organizational culture.

PubMed

Knapp, Susan

2015-01-01

The purpose of this paper is to examine the relationship between four organizational cultural types defined by the Competing Values Framework and three Lean Six Sigma implementation components - management involvement, use of Lean Six Sigma methods and Lean Six Sigma infrastructure. The study involved surveying 446 human resource and quality managers from 223 hospitals located in Maine, New Hampshire, Vermont, Massachusetts and Rhode Island using the Organizational Culture Assessment Instrument. Findings - In total, 104 completed responses were received and analyzed using multivariate analysis of variance. Follow-up analysis of variances showed management support was significant, F(3, 100)=4.89, p < 0.01, η2=1.28; infrastructure was not significant, F(3, 100)=1.55, p=0.21, η2=0.05; and using Lean Six Sigma methods was also not significant, F(3, 100)=1.34, p=0.26, η2=0.04. Post hoc analysis identified group and development cultures having significant interactions with management support. The relationship between organizational culture and Lean Six Sigma in hospitals provides information on how specific cultural characteristics impact the Lean Six Sigma initiative key components. This information assists hospital staff who are considering implementing quality initiatives by providing an understanding of what cultural values correspond to effective Lean Six Sigma implementation. Managers understanding the quality initiative cultural underpinnings, are attentive to the culture-shared values and norm's influence can utilize strategies to better implement Lean Six Sigma.

Lean in healthcare from employees' perspectives.

PubMed

Drotz, Erik; Poksinska, Bozena

2014-01-01

The purpose of this paper is to contribute toward a deeper understanding of the new roles, responsibilities, and job characteristics of employees in Lean healthcare organizations. The paper is based on three cases studies of healthcare organizations that are regarded as successful examples of Lean applications in the healthcare context. Data were collected by methods including interviews, observations, and document studies. The implementation of Lean in healthcare settings has had a great influence on the roles, responsibilities, and job characteristics of the employees. The focus has shifted from healthcare professionals, where clinical autonomy and professional skills have been the guarding principles of patient care, to process improvement and teamwork. Different job characteristics may make it difficult to implement certain Lean practices in healthcare. Teamwork and decentralization of authority are examples of Lean practices that could be considered countercultural because of the strong professional culture and uneven power distribution, with doctors as the dominant decision makers. Teamwork, value flow orientation, and company-wide involvement in CI were associated with positive effects on the organizations' working environment, staff development, and organizational performance. In order to succeed with Lean healthcare, it is important to understand and recognize the differences in job characteristics between Lean manufacturing and healthcare. This paper provides insights into how Lean implementation changes the roles, responsibilities, and job characteristics of healthcare staff and the challenges and implications that may follow from this.

Trunk lean gait decreases multi-segmental coordination in the vertical direction.

PubMed

Tokuda, Kazuki; Anan, Masaya; Sawada, Tomonori; Tanimoto, Kenji; Takeda, Takuya; Ogata, Yuta; Takahashi, Makoto; Kito, Nobuhiro; Shinkoda, Koichi

2017-11-01

[Purpose] The strategy of trunk lean gait to reduce external knee adduction moment (KAM) may affect multi-segmental synergy control of center of mass (COM) displacement. Uncontrolled manifold (UCM) analysis is an evaluation index to understand motor variability. The purpose of this study was to investigate how motor variability is affected by using UCM analysis on adjustment of the trunk lean angle. [Subjects and Methods] Fifteen healthy young adults walked at their preferred speed under two conditions: normal and trunk lean gait. UCM analysis was performed with respect to the COM displacement during the stance phase. The KAM data were analyzed at the points of the first KAM peak during the stance phase. [Results] The KAM during trunk lean gait was smaller than during normal gait. Despite a greater segmental configuration variance with respect to mediolateral COM displacement during trunk lean gait, the synergy index was not significantly different between the two conditions. The synergy index with respect to vertical COM displacement during trunk lean gait was smaller than that during normal gait. [Conclusion] These results suggest that trunk lean gait is effective in reducing KAM; however, it may decrease multi-segmental movement coordination of COM control in the vertical direction.

The challenges of lean manufacturing implementation in kitting assembly

NASA Astrophysics Data System (ADS)

Fansuri, A. F. H.; Rose, A. N. M.; Nik Mohamed, N. M. Z.; Ahmad, H.

2017-10-01

Literature studies shows that lean manufacturing goes way back with the original founder Eli Whitney in year 1799. The main purpose of lean manufacturing is to identify and eliminate waste in production. The application of lean manufacturing can be carried out in any industrial processes with regards to the understanding of lean principles, theories and practices. Kitting is one of the important aspects in a successful production. The continuous supply of materials from store to production has to be systematic and able to achieve lean standard for it to be successful. The objective of this paper is to review the implementation of lean manufacturing in kitting assembly. Previous papers show that, the implementation of lean manufacturing in kitting assembly may be beneficial to the organization such as reduce in space occupancy, part shortages, lead time and manpower. Based on previous research, some industries may tend to change between kitting and line stocking which are due to lack of understanding when implementing kitting and causes longer lead time and materials overflow in store. With a proper understanding on what to kit, where to kit, how to kit, why to kit and who kits the material with a standardised process flow may ensure the success of kitting.

A Basic Behavior of CNG DI Combustion in a Spark-Ignited Rapid Compression Machine

NASA Astrophysics Data System (ADS)

Huang, Zuohua; Shiga, Seiichi; Ueda, Takamasa; Jingu, Nobuhisa; Nakamura, Hisao; Ishima, Tsuneaki; Obokata, Tomio; Tsue, Mitsuhiro; Kono, Michikata

A basic characteristics of compressed natural gas direct-injection (CNG DI) combustion was studied by using a rapid compression machine. Results show that comparing with homogeneous mixture, CNG DI has short combustion duration, high pressure rise due to combustion, and high rate of heat release, which are considered to come from the charge stratification and the gas flow generated by the fuel injection. CNG DI can realize extremely lean combustion which reaches 0.03 equivalence ratio, φ. Combustion duration, maximum pressure rise due to combustion and combustion efficiency are found to be insensitive to the injection modes. Unburned methane showed almost the same level as that of homogeneous mixture combustion. CO increased steeply with the increase in φ when φ was greater than 0.8 due to the excessive stratification, and NOx peak value shifted to the region of lower φ. Combustion inefficiency maintains less than 0.08 in the range of φ from 0.1 to 0.9 and increases at very low φ due to bulk quenching and at higher φ due to excessive stratification. The combustion efficiency estimated from combustion products shows good agreement with that of heat release analysis.

Leadership requirements for Lean versus servant leadership in health care: a systematic review of the literature

PubMed Central

Aij, Kjeld Harald; Rapsaniotis, Sofia

2017-01-01

As health care organizations face pressures to improve quality and efficiency while reducing costs, leaders are adopting management techniques and tools used in manufacturing and other industries, especially Lean. Successful Lean leaders appear to use a coaching leadership style that shares underlying principles with servant leadership. There is little information about specific similarities and differences between Lean and servant leaderships. We systematically reviewed the literature on Lean leadership, servant leadership, and health care and performed a comparative analysis of attributes using Russell and Stone’s leadership framework. We found significant overlap between the two leadership styles, although there were notable differences in origins, philosophy, characteristics and behaviors, and tools. We conclude that both Lean and servant leaderships are promising models that can contribute to the delivery of patient-centered, high-value care. Servant leadership may provide the means to engage and develop employees to become successful Lean leaders in health care organizations. PMID:29355240

The impact of genetics on retail meat value in Australian lamb.

PubMed

Anderson, F; Pethick, D W; Gardner, G E

2016-07-01

Lean (muscle), fat, and bone composition of 1554 lamb carcasses from Maternal, Merino and Terminal sired lambs was measured using computed tomography scanning. Lamb sires were diverse in their range of Australian Sheep Breeding Values for post weaning c-site eye muscle depth (PEMD) and fat depth (PFAT), and post weaning weight (PWWT). Lean value, representing predicted lean weight multiplied by retail value, was determined for lambs at the same carcass weight or the same age. At the same carcass weight, lean value was increased the most by reducing sire PFAT, followed by increasing PEMD and PWWT. However for lambs of the same age, increasing sire PWWT increased lean value the most. Terminal sired lambs, on average, had greater lean value irrespective of whether comparisons were made at the same age or weight. Lean value was greater in Merino compared to Maternal sired lambs at equal carcass weight, however the reverse was true when comparisons were made at the same age. Copyright © 2016 Elsevier Ltd. All rights reserved.

Method for automatically evaluating a transition from a batch manufacturing technique to a lean manufacturing technique

DOEpatents

Ivezic, Nenad; Potok, Thomas E.

2003-09-30

A method for automatically evaluating a manufacturing technique comprises the steps of: receiving from a user manufacturing process step parameters characterizing a manufacturing process; accepting from the user a selection for an analysis of a particular lean manufacturing technique; automatically compiling process step data for each process step in the manufacturing process; automatically calculating process metrics from a summation of the compiled process step data for each process step; and, presenting the automatically calculated process metrics to the user. A method for evaluating a transition from a batch manufacturing technique to a lean manufacturing technique can comprise the steps of: collecting manufacturing process step characterization parameters; selecting a lean manufacturing technique for analysis; communicating the selected lean manufacturing technique and the manufacturing process step characterization parameters to an automatic manufacturing technique evaluation engine having a mathematical model for generating manufacturing technique evaluation data; and, using the lean manufacturing technique evaluation data to determine whether to transition from an existing manufacturing technique to the selected lean manufacturing technique.

The promise of Lean in health care.

PubMed

Toussaint, John S; Berry, Leonard L

2013-01-01

An urgent need in American health care is improving quality and efficiency while controlling costs. One promising management approach implemented by some leading health care institutions is Lean, a quality improvement philosophy and set of principles originated by the Toyota Motor Company. Health care cases reveal that Lean is as applicable in complex knowledge work as it is in assembly-line manufacturing. When well executed, Lean transforms how an organization works and creates an insatiable quest for improvement. In this article, we define Lean and present 6 principles that constitute the essential dynamic of Lean management: attitude of continuous improvement, value creation, unity of purpose, respect for front-line workers, visual tracking, and flexible regimentation. Health care case studies illustrate each principle. The goal of this article is to provide a template for health care leaders to use in considering the implementation of the Lean management system or in assessing the current state of implementation in their organizations. Copyright © 2013 Mayo Foundation for Medical Education and Research. Published by Elsevier Inc. All rights reserved.

Lean sigma--will it work for healthcare?

PubMed

Bahensky, James A; Roe, Janet; Bolton, Romy

2005-01-01

The manufacturing industry has been using Lean Sigma for years in pursuit of continuous improvement to obtain a competitive advantage. The objectives of these efforts are to use the Lean techniques for reducing cycle times and the Six Sigma concepts for reducing product defects. The Iowa Business Council with several advocates worked with the University of Iowa Hospital and Clinics (UIHC) and two other Iowa hospitals to determine whether Lean Sigma is adaptable in healthcare. A team of 15 people at UIHC used the Kaizen Breakthrough Methodology over a five-day period in an aggressive identification and elimination of non-value added activities in Radiology CT scanning. The results exceeded the initial project objectives and indicated that Lean Sigma is applicable in healthcare. Overall, the Lean Sigma project increased revenue by approximately $750,000 per year. The Kaizen process proved to be successful and interesting. Within three days, the team installed new work flow processes. This implementation-oriented approach is what differentiates Lean Sigma from other quality improvement processes.

Leaning to the left makes the Eiffel Tower seem smaller: posture-modulated estimation.

PubMed

Eerland, Anita; Guadalupe, Tulio M; Zwaan, Rolf A

2011-12-01

In two experiments, we investigated whether body posture influences people's estimation of quantities. According to the mental-number-line theory, people mentally represent numbers along a line with smaller numbers on the left and larger numbers on the right. We hypothesized that surreptitiously making people lean to the right or to the left would affect their quantitative estimates. Participants answered estimation questions while standing on a Wii Balance Board. Posture was manipulated within subjects so that participants answered some questions while they leaned slightly to the left, some questions while they leaned slightly to the right, and some questions while they stood upright. Crucially, participants were not aware of this manipulation. Estimates were significantly smaller when participants leaned to the left than when they leaned to the right.

Effects of enhanced atmospheric ammonia on physiological characteristics of maize(Zea mays L.).

PubMed

Chen, Xiaoli; Li, Shiqing

2013-09-01

Elevated atmospheric NH₃ may affect photosynthesis rates and biomass production of crops and the effect may be responsible for the soil nitrogen (N) levels. Plants were exposed to 0 and 1000 nL L⁻¹ with and without N (+N and - N) in open-top chambers (OTCs) to investigate effects of atmospheric NH₃ on photosynthetic and chlorophyll fluorescence parameters of maize plants. At two N levels, NH₃ exposure at 1000 nL L⁻¹ led to an increase in plant height, biomass production, net photosynthetic rates (P(n)) and stomatal conductance (g(s)) compared to ambient NH₃. Exposure to 1000 nL L⁻¹ NH₃ resulted in a significantly higher photochemical quenching (q(p)) and non-photochemical quenching (q(np)), while minimal fluorescence (F(o)), maximum fluorescence (F(m)) and maximum photochemical efficiency (F(v)/F(m)) were not affected. For shoots, N concentrations for - N-1000 and + N-1000 treatments were 49-50% and 26-30% higher, respectively, than those of - N-0 and + N-0 treatments. No visible damage was observed and plants growing on low soil N took up more leaf-derived N than those fertilised at higher N level. Therefore, atmospheric NH₃ can be considered as a quick fertiliser for crops and should be estimated in a further study with soil N fertilisers in order to reduce the dosage. © 2013 Society of Chemical Industry.

Quench protection diode irradiation tests by the Texas Accelerator Center

DOE Office of Scientific and Technical Information (OSTI.GOV)

Carcagno, R.; Weichold, M.; Welch, G.

1986-07-14

To date considerable progress has been made in the first stage of the TAC program to assess the use of Quench protection diodes (QPD) within the cold region of the SSC superconducting magnets. Our principle goal in this period was to experimentally obtain information that will assist us in designing apparatus for future tests. More specifically, we wished to address the following areas of uncertainty: operational difficulties associated with installing and operating an experiment at a nuclear reactor; diode behavior when subjected to neutron radiation while held close to the temperature of liquid nitrogen; and the extent to which diodesmore » can be annealed by heating them up to 593/degree/K. To gain information in these areas, we performed an irradiation of sixteen Westinghouse diodes at the Texas A and M Nuclear Science Center reactor. In the interest of avoiding the expense and long lead times associated with obtaining new equipment, we used apparatus that was on hand or which could be quickly obtained or constructed. Further tests of the irradiated diodes and analysis of the data already acquired will be continuing for some time, but the results already available will allow us to proceed with designing apparatus for accurate and reliable irradiation testing of diodes. The following is a summary of what we have learned in the three areas mentioned above, some cautions about interpreting the data, and the implications of this new information for our future activities. 14 figs., 1 tab.« less

Evaluation de l'effet des concepts de la production allegee dans une entreprise aeronautique

NASA Astrophysics Data System (ADS)

Moknine, Myriam

This research focuses on a project to implement a Lean approach in Quebec's aerospace business, that of Bombardier Aerospace. Developed for the automobile industry since the 1950s, the Lean has expanded its practices to various industry sectors, including the international aircraft industry, and more specifically the Quebec aircraft industry. Today, numerous companies turn more and more to the Lean Manufacturing approach to improve their competitiveness and their performance levels. The review of the literature on the Lean has allowed us to further understand the topic and more specifically its application in the aerospace sector. The Lean approach allows the improvement of operational performance indicators such as the reduction of production costs, cycle times, travel and inventories, as well as the improvement of the versatility of employees. The Lean has succeeded where many other organisational models have failed. Several success factors such as employee involvement, leadership commitment, proper integration of all tools and many others must be used in the implementation of such production practice. However, this approach is sometimes criticized by some authors who suggest that the improvements made by the Lean result in an increase in the workload of employees and a deterioration of their stress levels. Our research on the Lean has revealed gaps in available and existing research and data on the subject, particularly in the aerospace sector. This research has helped to fill this important gap, by documenting the context and highlighting the impact of the Lean on a production system in the Quebec aerospace components. A machining center having deployed a Lean approach was chosen to conduct a case study in post-implantation. Tools for data collection such as observations on the production floor, semi-structured interviews, as well as the Lean checklist, were used to perform this case study. The case study has confirmed the positive impact of Lean on operational performance indicators of the company. The results of this case study showed a reduction of cycle time of 49%, a reduction of unnecessary employee travels of 50% and a reduction of production costs by about 50%. In addition to these positive discoveries, our study has highlighted an important human benefit in the business such as an improvement in the versatility of employees by 25%. In addition, the study also demonstrated that the integration and assimilation of the Lean concepts is made with a proven success. Indeed, analysis on results from the checklist showed that the level of Lean concepts maturity progressed favorably in the period from pre-project until that in post-project. This research brings an added value to the scientific literature. It thus helps to disseminate data in a Lean implementation in a production area of Quebec aerospace products.

The Lean and Environment Toolkit

EPA Pesticide Factsheets

This Lean and Environment Toolkit assembles practical experience collected by the U.S. Environmental Protection Agency (EPA) and partner companies and organizations that have experience with coordinating Lean implementation and environmental management.

Exploring the Development of Competence in Lean Management through Action Learning Groups: A Study of the Introduction of Lean to a Facilities Management Function

ERIC Educational Resources Information Center

Wyton, Paul; Payne, Robin

2014-01-01

The introduction of a Lean approach to management requires the development of understanding and capability. This in turn requires a structured training intervention and other supporting activities. This paper explores, through a case study, the way in which action learning groups (ALGs) supported the development of Lean capabilities in the…

Lean and leadership practices: development of an initial realist program theory.

PubMed

Goodridge, Donna; Westhorp, Gill; Rotter, Thomas; Dobson, Roy; Bath, Brenna

2015-09-07

Lean as a management system has been increasingly adopted in health care settings in an effort to enhance quality, capacity and safety, while simultaneously containing or reducing costs. The Ministry of Health in the province of Saskatchewan, Canada has made a multi-million dollar investment in Lean initiatives to create "better health, better value, better care, and better teams", affording a unique opportunity to advance our understanding of the way in which Lean philosophy, principles and tools work in health care. In order to address the questions, "What changes in leadership practices are associated with the implementation of Lean?" and "When leadership practices change, how do the changed practices contribute to subsequent outcomes?", we used a qualitative, multi-stage approach to work towards developing an initial realist program theory. We describe the implications of realist assumptions for evaluation of this Lean initiative. Formal theories including Normalization Process Theory, Theories of Double Loop and Organization Leaning and the Theory of Cognitive Dissonance help understand this initial rough program theory. Data collection included: key informant consultation; a stakeholder workshop; documentary review; 26 audiotaped and transcribed interviews with health region personnel; and team discussions. A set of seven initial hypotheses regarding the manner in which Lean changes leadership practices were developed from our data. We hypothesized that Lean, as implemented in this particular setting, changes leadership practices in the following ways. Lean: a) aligns the aims and objectives of health regions; b) authorizes attention and resources to quality improvement and change management c) provides an integrated set of tools for particular tasks; d) changes leaders' attitudes or beliefs about appropriate leadership and management styles and behaviors; e) demands increased levels of expertise, accountability and commitment from leaders; f) measures and uses data effectively to identify actual and relevant local problems and the root causes of those problems; and g) creates or supports a 'learning organization' culture. This study has generated initial hypotheses and realist program theory that can form the basis for future evaluation of Lean initiatives. Developing leadership capacity and culture is theorized to be a necessary precursor to other systemic and observable changes arising from Lean initiatives.

Modelling Lean and Green Supply Chain

NASA Astrophysics Data System (ADS)

Duarte, Susana Carla Vieira Lino Medina

The success of an organization depends on the effective control of its supply chain. It is important to recognize new opportunities for organization and its supply chain. In the last few years the approach to lean, agile, resilient and green supply chain paradigms has been addressed in the scientific literature. Research in this field shows that the integration of these concepts revealed some contradictions among so many paradigms. This thesis is mainly focused on the lean and green approaches. Thirteen different management frameworks, embodied in awards, standards and tools were studied to understand if they could contribute for the modelling process of a lean and green approach. The study reveals a number of categories that are common in most management frameworks, providing adequate conditions for a lean and green supply chain transformation. A conceptual framework for the evaluation of a lean and green organization`s supply chain was proposed. The framework considers six key criteria, namely, leadership, people, strategic planning, stakeholders, processes and results. It was proposed an assessment method considering a criteria score for each criterion. The purpose is to understand how lean and green supply chain can be compatible, using principles, practices, techniques or tools (i.e. elements) that support both, a lean and a green approach, in all key criteria. A case study in the automotive upstream supply chain was performed to understand more deeply if the elements proposed for the conceptual framework could be implemented in a real-scenario. Based on the conceptual framework and the case study, a roadmap to achieve a lean-green transformation is presented. The proposed roadmap revealed its contribution to the understanding on how and when an organization`s supply chain should apply the lean and green elements. This study is relevant to practice, as it may assist managers in the adoption of a lean and green supply chain approach, giving insights for the implementation of a hybrid supply chain.

Experiences of leaders in the implementation of Lean in a teaching hospital—barriers and facilitators in clinical practices: a qualitative study

PubMed Central

Aij, Kjeld Harald; Simons, Frederique Elisabeth; Widdershoven, Guy A M; Visse, Merel

2013-01-01

Objectives To date, experiences of leaders in the implementation of Lean after a Lean Training Programme have not been systematically investigated within teaching hospitals. Existing studies have identified barriers and facilitators only from an improvement programme perspective and have not considered the experiences of leaders themselves. This study aims to bridge this gap. Design Semistructured, indepth interviews. Setting One of largest teaching hospitals in the Netherlands. Participants 31 medical, surgical and nursing professionals with an average of 19.2 years of supervisory experience. All professionals were appointed to a Lean Training Programme and were directly involved in the implementation of Lean. Results The evidence obtained in this study shows that, from the perspectives of participants, leadership management support, a continuous learning environment and cross-departmental cooperation play a significant role in successful Lean implementation. The results suggest that a Lean Training Programme contributed to positive outcomes in personal and professional skills that were evident during the first 4 months after programme completion. Conclusions Implementing Lean in a teaching hospital setting is a challenge because of the ambiguous and complex environment of a highly professionalised organisation. The study found that leadership management support and a continuous learning environment are important facilitators of Lean implementation. To increase the successful outcomes of leadership actions, training should be supplemented with actions to remove perceived barriers. This requires the involvement of all professionals, the crossing of departmental boundaries and a focus on meaning-making processes rather than simply ‘implementing’ facts. Therefore, this research suggests that programme participants, such as staff members and leaders, can mutually explore the meanings of Lean thinking and working for their own contexts. By entering this shared learning process (eg, learning on the job) the ownership of Lean implementation could also increase. PMID:24171938

A questionnaire measuring staff perceptions of Lean adoption in healthcare: development and psychometric testing.

PubMed

Kaltenbrunner, Monica; Bengtsson, Lars; Mathiassen, Svend Erik; Engström, Maria

2017-03-24

During the past decade, the concept of Lean has spread rapidly within the healthcare sector, but there is a lack of instruments that can measure staff's perceptions of Lean adoption. Thus, the aim of the present study was to develop a questionnaire measuring Lean in healthcare, based on Liker's description of Lean, by adapting an existing instrument developed for the service sector. A mixed-method design was used. Initially, items from the service sector instrument were categorized according to Liker's 14 principles describing Lean within four domains: philosophy, processes, people and partners and problem-solving. Items were lacking for three of Liker's principles and were therefore developed de novo. Think-aloud interviews were conducted with 12 healthcare staff from different professions to contextualize and examine the face validity of the questionnaire prototype. Thereafter, the adjusted questionnaire's psychometric properties were assessed on the basis of a cross-sectional survey among 386 staff working in primary care. The think-aloud interviews led to adjustments in the questionnaire to better suit a healthcare context, and the number of items was reduced. Confirmatory factor analysis of the adjusted questionnaire showed a generally acceptable correspondence with Liker's description of Lean. Internal consistency, measured using Cronbach's alpha, for the factors in Liker's description of Lean was 0.60 for the factor people and partners, and over 0.70 for the three other factors. Test-retest reliability measured by the intra-class correlation coefficient ranged from 0.77 to 0.88 for the four factors. We designed a questionnaire capturing staff's perceptions of Lean adoption in healthcare on the basis of Liker's description. This Lean in Healthcare Questionnaire (LiHcQ) showed generally acceptable psychometric properties, which supports its usability for measuring Lean adoption in healthcare. We suggest that further research focus on verifying the usability of LiHcQ in other healthcare settings, and on adjusting the instrument if needed.

Relationship Between Changes in Fat and Lean Depots Following Weight Loss and Changes in Cardiovascular Disease Risk Markers.

PubMed

Clifton, Peter M

2018-04-04

Gluteofemoral fat mass has been associated with improved cardiovascular disease risk factors. It is not clear if loss of this protective fat during weight loss partially negates the effect of loss of visceral fat. The aim of this study was to examine regional fat loss in a large weight-loss cohort from one center and to determine if fat loss in the leg and total lean tissue loss is harmful. We combined the data from 7 of our previously published 3-month weight-loss studies and examined the relationship between regional fat and lean tissue loss and changes in cardiovascular disease risk factors in 399 participants. At baseline, leg fat was positively associated with high-density lipoprotein cholesterol in women and inversely with fasting triglyceride level in both sexes. Abdominal lean tissue was also related to systolic blood pressure in men. Changes in regional fat and lean tissue were positively associated with changes in glucose, insulin, total cholesterol, triglycerides, low-density lipoprotein cholesterol and systolic and diastolic blood pressure ( r =0.11-0.22, P <0.05) with leg fat and arm lean tissue dominating in multivariate regression. After adjustment for total weight or total fat change, these relationships disappeared except for a positive relationship between arm and lean leg mass loss and changes in triglycerides and systolic blood pressure. Loss of leg fat and leg lean tissue was directly associated with beneficial changes in cardiovascular disease risk markers. Loss of lean tissue may not have an adverse effect on cardiovascular disease risk, and measures to retain lean tissue during weight loss may not be necessary. © 2018 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.

The effect of high-fat diet on the composition of the gut microbiota in cloned and non-cloned pigs of lean and obese phenotype

PubMed Central

Pedersen, Rebecca; Andersen, Anders Daniel; Hermann-Bank, Marie Louise; Stagsted, Jan; Boye, Mette

2013-01-01

The aim of this study was to investigate the effect of high-far-high-energy diet on cloned and non-cloned domestic pigs of both lean and obese phenotype and to evaluate if the lean cloned pigs had a lower inter-individual variation as compared with non-cloned pigs. The microbiota of colon and terminal ileum was investigated in cloned and non-cloned pigs that received a high-far-high-energy diet with either restricted or ad libitum access to feed, resulting in lean and obese phenotypes, respectively. The fecal microbiota of lean pigs was investigated by terminal restriction fragment length polymorphism (T-RFLP). The intestinal microbiota of lean and obese cloned and non-cloned pigs was analyzed by quantitative real time PCR and a novel high-throughput qPCR platform (Fluidigm). Principal component analysis (PCA) of the T-RFLP profiles revealed that lean cloned and non-cloned pigs had a different overall composition of their gut microbiota. The colon of lean cloned pigs contained relatively more bacteria belonging to the phylum Firmicutes and less from the phylum Bacteroidetes than obese cloned pigs as estimated by qPCR. Fluidigm qPCR results revealed differences in specific bacterial groups in the gut microbiota of both lean and obese pigs. Our results suggest that high-far-high-energy diet is associated with changes in the gut microbiota even in the absence of obesity. Overall, the cloned pigs had a different gut microbiota from that of non-cloned pigs. To our knowledge this is the first study to investigate the gut microbiota of cloned domestic pigs of lean and obese phenotype. PMID:23974297

Clinical and Metabolic Characterization of Lean Caucasian Subjects With Non-alcoholic Fatty Liver.

PubMed

Feldman, Alexandra; Eder, Sebastian K; Felder, Thomas K; Kedenko, Lyudmyla; Paulweber, Bernhard; Stadlmayr, Andreas; Huber-Schönauer, Ursula; Niederseer, David; Stickel, Felix; Auer, Simon; Haschke-Becher, Elisabeth; Patsch, Wolfgang; Datz, Christian; Aigner, Elmar

2017-01-01

Non-alcoholic fatty liver disease (NAFLD) is closely linked to obesity; however, 5-8% of lean subjects also have evidence of NAFLD. We aimed to investigate clinical, genetic, metabolic and lifestyle characteristics in lean Caucasian subjects with NAFLD. Data from 187 subjects allocated to one of the three groups according to body mass index (BMI) and hepatic steatosis on ultrasound were obtained: lean healthy (BMI≤25 kg/m 2 , no steatosis, N=71), lean NAFLD (BMI≤25 kg/m 2 , steatosis, N=55), obese NAFLD (BMI≥30 kg/m 2 , steatosis; N=61). All subjects received a detailed clinical and laboratory examination including oral glucose tolerance test. The serum metabolome was assessed using the Metabolomics AbsoluteIDQ p180 kit (BIOCRATES Life Sciences). Genotyping for single-nucleotide polymorphisms (SNPs) associated with NAFLD was performed. Lean NAFLD subjects had fasting insulin concentrations similar to lean healthy subjects but had markedly impaired glucose tolerance. Lean NAFLD subjects had a higher rate of the mutant PNPLA3 CG/GG variant compared to lean controls (P=0.007). Serum adiponectin concentrations were decreased in both NAFLD groups compared to controls (P<0.001 for both groups) The metabolomics study revealed a potential role for various lysophosphatidylcholines (lyso-PC C18:0, lyso-PC C17:0) and phosphatidylcholines (PCaa C36:3; false discovery rate (FDR)-corrected P-value<0.001) as well as lysine, tyrosine, and valine (FDR<0.001). Lean subjects with evidence of NAFLD have clinically relevant impaired glucose tolerance, low adiponectin concentrations and a distinct metabolite profile with an increased rate of PNPLA3 risk allele carriage.

Weight-adjusted lean body mass and calf circumference are protective against obesity-associated insulin resistance and metabolic abnormalities.

PubMed

Takamura, Toshinari; Kita, Yuki; Nakagen, Masatoshi; Sakurai, Masaru; Isobe, Yuki; Takeshita, Yumie; Kawai, Kohzo; Urabe, Takeshi; Kaneko, Shuichi

2017-07-01

To test the hypothesis that preserved muscle mass is protective against obesity-associated insulin resistance and metabolic abnormalities, we analyzed the relationship of lean body mass and computed tomography-assessed sectional areas of specific skeletal muscles with insulin resistance and metabolic abnormalities in a healthy cohort. A total of 195 subjects without diabetes who had completed a medical examination were included in this study. Various anthropometric indices such as circumferences of the arm, waist, hip, thigh, and calf were measured. Body composition (fat and lean body mass) was determined by bioelectrical impedance analysis. Sectional areas of specific skeletal muscles (iliopsoas, erector spinae, gluteus, femoris, and rectus abdominis muscles) were measured using computed tomography. Fat and lean body mass were significantly correlated with metabolic abnormalities and insulin resistance indices. When adjusted by weight, relationships of fat and lean body mass with metabolic parameters were mirror images of each other. The weight-adjusted lean body mass negatively correlated with systolic and diastolic blood pressures; fasting plasma glucose, HbA1c, alanine aminotransferase, and triglyceride, and insulin levels; and hepatic insulin resistance indices, and positively correlated with HDL-cholesterol levels and muscle insulin sensitivity indices. Compared with weight-adjusted lean body mass, weight-adjusted sectional areas of specific skeletal muscles showed similar, but not as strong, correlations with metabolic parameters. Among anthropometric measures, the calf circumference best reflected lean body mass, and weight-adjusted calf circumference negatively correlated with metabolic abnormalities and insulin resistance indices. Weight-adjusted lean body mass and skeletal muscle area are protective against weight-associated insulin resistance and metabolic abnormalities. The calf circumference reflects lean body mass and may be useful as a protective marker against obesity-associated metabolic abnormalities.

The effect of high-fat diet on the composition of the gut microbiota in cloned and non-cloned pigs of lean and obese phenotype.

PubMed

Pedersen, Rebecca; Andersen, Anders Daniel; Hermann-Bank, Marie Louise; Stagsted, Jan; Boye, Mette

2013-01-01

The aim of this study was to investigate the effect of high-far-high-energy diet on cloned and non-cloned domestic pigs of both lean and obese phenotype and to evaluate if the lean cloned pigs had a lower inter-individual variation as compared with non-cloned pigs. The microbiota of colon and terminal ileum was investigated in cloned and non-cloned pigs that received a high-far-high-energy diet with either restricted or ad libitum access to feed, resulting in lean and obese phenotypes, respectively. The fecal microbiota of lean pigs was investigated by terminal restriction fragment length polymorphism (T-RFLP). The intestinal microbiota of lean and obese cloned and non-cloned pigs was analyzed by quantitative real time PCR and a novel high-throughput qPCR platform (Fluidigm). Principal component analysis (PCA) of the T-RFLP profiles revealed that lean cloned and non-cloned pigs had a different overall composition of their gut microbiota. The colon of lean cloned pigs contained relatively more bacteria belonging to the phylum Firmicutes and less from the phylum Bacteroidetes than obese cloned pigs as estimated by qPCR. Fluidigm qPCR results revealed differences in specific bacterial groups in the gut microbiota of both lean and obese pigs. Our results suggest that high-far-high-energy diet is associated with changes in the gut microbiota even in the absence of obesity. Overall, the cloned pigs had a different gut microbiota from that of non-cloned pigs. To our knowledge this is the first study to investigate the gut microbiota of cloned domestic pigs of lean and obese phenotype.

Effects of age and lean direction on the threshold of single-step balance recovery in younger, middle-aged and older adults.

PubMed

Carbonneau, Evelyne; Smeesters, Cécile

2014-01-01

Several studies have quantified and compared balance recovery between healthy younger and older adults, using a variety of large postural perturbations and loss of balance directions. However, to the best of our knowledge, no studies at the threshold of balance recovery, where avoiding a fall is not always possible, have included middle-aged adults. We thus determined the maximum lean angle from which 20 younger, 16 middle-aged and 16 older healthy adults could be suddenly released and still recover balance using a single step for forward, sideways and backward leans. Results showed that the maximum lean angles of younger adults were 23% greater than middle-aged adults and 48% greater than older adults. The maximum lean angles for forward leans were 23% greater than sideways leans and 22% greater than backward leans. These declines with age and lean direction were associated with declines in response initiation, execution and geometry. Finally exponential regressions showed that the critical ages at which the ability to recover balance and avoid a fall significantly decreases were 51.0, 60.6 and 69.9 yrs for forward, sideways and backward leans, respectively. Therefore, we have demonstrated that age affects the ability to recover balance nearly a decade earlier than the rate of falls. Future studies should thus not only include older adults over 65 yrs, but also middle-aged adults under 65 yrs, or recruit all ages from 18 to 85 yrs. Finally, the critical ages identified in this study may justify an earlier screening of aging adults to prevent future falls, especially the first fall. Copyright © 2013 Elsevier B.V. All rights reserved.

Adipokines, oxidized low-density lipoprotein, and C-reactive protein levels in lean, overweight, and obese portuguese patients with type 2 diabetes.

PubMed

Neuparth, Maria João; Proença, Jorge Brandão; Santos-Silva, Alice; Coimbra, Susana

2013-01-01

Aim. Our aim was to study how different BMI scores may influence the levels of inflammation, oxidative stress, adipogenesis, glucose, and lipid metabolism, in lean, overweight, and obese Portuguese patients with type 2 diabetes mellitus (T2DM). Methods. We studied 28 lean, 38 overweight, and 17 obese patients with T2DM and 20 controls (gender and age matched). The circulating levels of oxLDL, CRP, and some adipokines-adiponectin, leptin, and chemerin-and the lipid profile were evaluated. Results. Obese patients presented significantly lower levels of adiponectin and higher leptin, oxLDL, and chemerin levels, as compared to the overweight, lean, and control groups. Overweight, compared to lean and control, subjects showed significantly lower adiponectin and higher leptin and chemerin levels; oxLDL values were significantly higher in overweight than in lean patients. Lean patients presented significantly higher chemerin values than the control. Obese patients presented significantly higher CRP values, as compared to lean patients and the control group. Obese and overweight patients presented significantly higher triglycerides values than lean patients. Except for CRP, all the observed significant changes between control and patients remained significant after statistical adjustment for the body mass index (BMI). Conclusion. The levels of leptin, adiponectin, oxLDL, CRP, and triglycerides in patients with T2DM seem to be more associated with obesity and less with diabetes. Chemerin levels were raised in lean, overweight, and obese patients, suggesting that, independently of BMI, an adipocyte dysfunction occurs. Moreover, chemerin may provide an important early biomarker of adipocyte dysfunction and a link between obesity and type 2 diabetes mellitus.

Adipokines, Oxidized Low-Density Lipoprotein, and C-Reactive Protein Levels in Lean, Overweight, and Obese Portuguese Patients with Type 2 Diabetes

PubMed Central

Neuparth, Maria João; Proença, Jorge Brandão; Santos-Silva, Alice; Coimbra, Susana

2013-01-01

Aim. Our aim was to study how different BMI scores may influence the levels of inflammation, oxidative stress, adipogenesis, glucose, and lipid metabolism, in lean, overweight, and obese Portuguese patients with type 2 diabetes mellitus (T2DM). Methods. We studied 28 lean, 38 overweight, and 17 obese patients with T2DM and 20 controls (gender and age matched). The circulating levels of oxLDL, CRP, and some adipokines—adiponectin, leptin, and chemerin—and the lipid profile were evaluated. Results. Obese patients presented significantly lower levels of adiponectin and higher leptin, oxLDL, and chemerin levels, as compared to the overweight, lean, and control groups. Overweight, compared to lean and control, subjects showed significantly lower adiponectin and higher leptin and chemerin levels; oxLDL values were significantly higher in overweight than in lean patients. Lean patients presented significantly higher chemerin values than the control. Obese patients presented significantly higher CRP values, as compared to lean patients and the control group. Obese and overweight patients presented significantly higher triglycerides values than lean patients. Except for CRP, all the observed significant changes between control and patients remained significant after statistical adjustment for the body mass index (BMI). Conclusion. The levels of leptin, adiponectin, oxLDL, CRP, and triglycerides in patients with T2DM seem to be more associated with obesity and less with diabetes. Chemerin levels were raised in lean, overweight, and obese patients, suggesting that, independently of BMI, an adipocyte dysfunction occurs. Moreover, chemerin may provide an important early biomarker of adipocyte dysfunction and a link between obesity and type 2 diabetes mellitus. PMID:24634792

Lean health care: what can hospitals learn from a world-class automaker?

PubMed

Kim, Christopher S; Spahlinger, David A; Kin, Jeanne M; Billi, John E

2006-05-01

With health care costs continuing to rise, a variety of process improvement methodologies have been proposed to address the reported inefficiencies in health care delivery. Lean production is one such method. The management philosophy and tools of lean production come from the manufacturing industry, where they were pioneered by Toyota Motor Corporation, which is viewed as the leader in utilizing these performance improvement methods. Lean has already enjoyed tremendous success in improving quality and efficiency in both the manufacturing and the service sector industries. Health care systems have just begun to utilize lean methods, with reports of improvements just beginning to appear in the literature. We describe some of the basic philosophy and principles of lean production methods and how these concepts can be applied in the health care environment. We describe some of the early success stories and ongoing endeavors of lean production in various health care organizations. We believe the hospital is an ideal setting for use of the lean production method, which could significantly affect how health care is delivered to patients. We conclude by discussing some of the potential challenges in introducing and implementing lean production methods in the health care environment. Lean production is a novel approach to delivering high-quality and efficient care to patients, and we believe that the health care sector can anticipate the same high level of success that the manufacturing and service industries have achieved using this approach. Hospitalists are primed to take action in delivering care of greater quality with more efficiency by applying these new principles in the hospital setting. (c) 2006 Society of Hospital Medicine.

Lean muscle mass in classic or ovulatory PCOS: association with central obesity and insulin resistance.

PubMed

Mario, F M; do Amarante, F; Toscani, M K; Spritzer, P M

2012-10-01

This age-matched case-control study assessed total and segmental lean muscle mass in classic or ovulatory polycystic ovary syndrome (PCOS) patients and investigated whether lean mass is associated with hormone and metabolic features. Participants underwent anthropometric and clinical evaluation. Habitual physical activity was assessed with a digital pedometer, and body composition by dual-energy X-ray absorptiometry. Laboratory measurements included total cholesterol, cholesterol fractions, triglycerides, glucose, total serum testosterone, serum insulin, estradiol, luteinizing hormone, and SHBG. Energy intake was calculated using a food frequency questionnaire. Classic PCOS patients had higher body mass index (BMI), waist circumference, testosterone and lipid accumulation product values than ovulatory PCOS and controls. Energy consumption, homeostasis model assessment index, SHBG, free androgen index and triglycerides, total and trunk lean mass were higher only in classic PCOS women vs. controls. Arm, leg, trunk, total or limb lean masses were not correlated with hormone levels in any of the groups. However, in PCOS women lipid accumulation product was positively correlated with total (r=0.56, p=0.001), trunk (r=0.59, p=0.001), arm (r=0.54, p=0.001), leg (r=0.44, p=0.03) and limb (r=0.48, p=0.001) lean masses. BMI was positively correlated with all lean mass segments and independently associated with total lean mass. Lipid accumulation product and BMI were independently associated with trunk lean mass variation. The increase in lean mass in classic PCOS appears to be associated with insulin resistance and central obesity rather than with energy intake, physical activity or androgens. © J. A. Barth Verlag in Georg Thieme Verlag KG Stuttgart · New York.

Ordering kinetics in the long-period superlattice alloy Cu0.79 Pd0.21

NASA Astrophysics Data System (ADS)

Wang, X.; Mainville, J.; Ludwig, K.; Flament, X.; Finel, A.; Caudron, R.

2005-07-01

The kinetics of long-period superlattice (LPS) formation from the disordered state has been examined in a Cu0.79Pd0.21 alloy that exhibits a one-dimensional LPS ordered state. Time-resolved x-ray scattering shows that, following a rapid temperature quench from the disordered state into the LPS region of the phase diagram, the satellite peaks initially grow more quickly than do the central integer-order superlattice peaks. During this process, the satellite peak position, which is inversely related to the average modulation wavelength 2M , initially decreases rapidly, then reaches a minimum and relaxes slowly back toward its new equilibrium position. In the later stages of the LPS formation process, the satellite and central integer-order superlattice peaks narrow in a manner consistent with t1/2 domain coarsening. A simple stochastic model of the partially ordered structure was developed to better understand the relationships between peak widths.

Plasma spraying method for forming diamond and diamond-like coatings

DOEpatents

Holcombe, Cressie E.; Seals, Roland D.; Price, R. Eugene

1997-01-01

A method and composition for the deposition of a thick layer (10) of diamond or diamond-like material. The method includes high temperature processing wherein a selected composition (12) including at least glassy carbon is heated in a direct current plasma arc device to a selected temperature above the softening point, in an inert atmosphere, and is propelled to quickly quenched on a selected substrate (20). The softened or molten composition (18) crystallizes on the substrate (20) to form a thick deposition layer (10) comprising at least a diamond or diamond-like material. The selected composition (12) includes at least glassy carbon as a primary constituent (14) and may include at least one secondary constituent (16). Preferably, the secondary constituents (16) are selected from the group consisting of at least diamond powder, boron carbide (B.sub.4 C) powder and mixtures thereof.

Lean in Air Permitting Guide

EPA Pesticide Factsheets

The Lean in Air Permitting Guide is designed to help air program managers at public agencies better understand the potential value and results that can be achieved by applying Lean improvement methods to air permitting processes.

Drive for leanness and health-related behavior within a social/cultural perspective.

PubMed

Tod, David; Edwards, Christian; Hall, Gareth

2013-09-01

We examined relationships between drive for leanness and perceived media pressure to change appearance, internalization of an ideal physique, exercise frequency, and dieting. Men and women (N=353) completed the Drive for Leanness Scale, the Sociocultural Attitudes Toward Appearance Questionnaire-3, the Eating Attitudes Test-26, and a demographic inventory. Drive for leanness was significantly correlated with athletic internalization (.52), pressure to attain an ideal physique (.25), exercise frequency (.36), and dieting (.25). Structural equation modeling revealed a good fitting model (χ(2)=2.85, p<.241; CFI=.99; NNFI=.98; RMSEA=.04; SRMR=.02) with internalization predicting drive for leanness, which in turn predicted dieting and exercise. Results reveal social/cultural theory helps enhance the understanding of the drive for leanness and its relationship with health-related behavior. Copyright © 2013 Elsevier Ltd. All rights reserved.

Effect of hormone therapy on lean body mass, falls, and fractures: Six-year results from the Women’s Health Initiative Hormone Trials

PubMed Central

Bea, Jennifer W.; Zhao, Qiuhong; Cauley, Jane A.; LaCroix, Andrea Z.; Bassford, Tamsen; Lewis, Cora E.; Jackson, Rebecca D.; Tylavsky, Frances A.; Chen, Zhao

2010-01-01

Objective Loss of lean body mass with aging may contribute to falls and fractures. The objective of this analysis was to determine if taking postmenopausal hormone therapy (HT: estrogen plus progestogen therapy, EPT or estrogen therapy alone, ET) favorably affects age-related changes in lean body mass and if these changes partially account for decreased falls or fractures with HT. Methods Participants randomly assigned to either EPT (n=543) or control (n=471) and ET (n= 453) or control (n= 474) and receiving dual-energy X-ray absorptiometry (DXA) scans to estimate body composition during the Women’s Health Initiative (WHI) were evaluated. Falls and fracture occurrence were obtained by annual self-report. Fractures were confirmed by clinical chart review. Results At 6yrs post-randomization, lean body mass was not different between HT and control groups. Although lean body mass positively influenced BMD, independent of HT status, the preserved lean body mass observed in the HT arms in the first 3 years did not significantly contribute to models evaluating HT influence on falls and fractures between years 3 and 6. Women taking at least 80% of their medication in the HT arms demonstrated fewer falls compared to placebo; this difference was not attributable to change in lean body mass. Conclusions Despite early preservation of lean body mass with HT (3years), HT did not ameliorate long-term (6 years) loss in lean body mass with aging. PMID:20689466

Effect of hormone therapy on lean body mass, falls, and fractures: 6-year results from the Women's Health Initiative hormone trials.

PubMed

Bea, Jennifer W; Zhao, Qiuhong; Cauley, Jane A; LaCroix, Andrea Z; Bassford, Tamsen; Lewis, Cora E; Jackson, Rebecca D; Tylavsky, Frances A; Chen, Zhao

2011-01-01

Loss of lean body mass with aging may contribute to falls and fractures. The objective of this analysis was to determine if taking postmenopausal hormone therapy (or HT: estrogen plus progestogen therapy or estrogen therapy alone) favorably affects age-related changes in lean body mass and if these changes partially account for decreased falls or fractures with HT. Participants randomly assigned to either estrogen plus progestogen therapy (n = 543) or control (n = 471) and estrogen therapy alone (n = 453) or control (n = 474) and receiving dual-energy x-ray absorptiometry scans to estimate body composition during the Women's Health Initiative were evaluated. Falls and fracture occurrence were obtained by annual self-report. Fractures were confirmed by a clinical chart review. At 6 years postrandomization, lean body mass was not different between HT and control groups. Although lean body mass positively influenced bone mineral density, independent of HT status, the preserved lean body mass observed in the HT arms in the first 3 years did not significantly contribute to models evaluating HT influence on falls and fractures between years 3 and 6. Women taking at least 80% of their medication in the HT arms demonstrated fewer falls compared with placebo; this difference was not attributable to change in lean body mass. Despite early preservation of lean body mass with HT (3 y), HT did not ameliorate long-term (6 y) loss in lean body mass with aging.

An exploratory analysis for Lean and Six Sigma implementation in hospitals: Together is better?

PubMed

Lee, Jung Young; McFadden, Kathleen L; Gowen, Charles R

Despite the increasing interest for Lean and Six Sigma implementations in hospitals, there has been little empirical evidence that goes beyond descriptive case studies to address the current status and the effectiveness of the implementations. The aim of this study was to explore existing patterns of Lean and Six Sigma implementation in U.S. hospitals and compare the performance of the different patterns. We collected data from 215 U.S. hospitals via a survey that includes measurement items developed from related literature. Using the cross-sectional data, we conducted a cluster analysis, followed by t tests, chi-square tests, and regression analyses for cluster verification. The cluster analysis identifies two clusters, a Moderate Six Sigma group and a Lean Six Sigma group. Results show that the Lean Six Sigma group outperforms the Moderate Six Sigma group across many performance dimensions: responsiveness capability, patient safety, and possibly cost saving. In addition, the Lean Six Sigma group tends to be composed of larger, private teaching hospitals located in more urban areas, and they employ more resources for quality improvement. Our research contributes to the quality management literature by supporting the possible complementary relationship between Lean and Six Sigma in hospitals. Our study encourages practitioners and managers to pay more attention to Lean implementation. Although Lean seems to be conducted in a limited fashion in many hospitals, it should be expanded and combined with Six Sigma for better results.

Serum visfatin in relation to insulin resistance and markers of hyperandrogenism in lean and obese women with polycystic ovary syndrome.

PubMed

Kowalska, Irina; Straczkowski, Marek; Nikolajuk, Agnieszka; Adamska, Agnieszka; Karczewska-Kupczewska, Monika; Otziomek, Elzbieta; Wolczynski, Slawomir; Gorska, Maria

2007-07-01

Visfatin, a protein secreted by adipose tissue, is suggested to play a role in pathogenesis of insulin resistance. In polycystic ovary syndrome (PCOS), insulin resistance might be involved in the development of endocrine and metabolic abnormalities. The aim of the study was to asses the relation between serum visfatin concentration and insulin sensitivity and markers of hyperandrogenism in lean and obese PCOS patients. The study group consisted of 70 women with PCOS (23 lean and 47 obese) and 45 healthy women (25 lean and 20 obese). Euglycemic hyperinsulinemic clamp and the measurements of serum visfatin, sex hormones were performed. The PCOS group had lower insulin sensitivity (P=0.00049) and higher serum visfatin (P=0.047) in comparison to the control group. The decrease in insulin sensitivity was present in both the lean (P=0.019) and obese (P=0.0077) PCOS subjects, whereas increase in serum visfatin was observed only in lean PCOS subjects (P=0.012). In the whole group, serum visfatin was negatively correlated with insulin sensitivity (r=-0.27, P=0.004). This relationship was also observed in the subgroup of lean (r=-0.30, P=0.038), but not obese women. Additionally, in lean women, visfatin was associated with serum testosterone (r=0.47, P=0.002) and free androgen index (r=0.48, P=0.002), independently of other potential confounding factors. Visfatin is associated with insulin resistance and markers of hyperandrogenism in lean PCOS patients.

Experimental investigations on effect of different materials and varying depths of one turn exhaust channel swiss roll combustor on its thermal performance

NASA Astrophysics Data System (ADS)

Mane Deshmukh, Sagar B.; Krishnamoorthy, A.; Bhojwani, V. K.; Pawane, Ashwini

2017-05-01

More energy density of hydrocarbon fuels compared to advanced batteries available in the market demands for development of systems which will use hydrocarbon fuels at small scale to generate power in small quantity (i.e. in few watts) and device efficiency should be reasonably good, but the basic requirement is to generate heat from the fuels like methane, propane, hydrogen, LPG and converting into power. Swiss roll combustor has proved to be best combustor at small scale. Present work is carried out on one turn exhaust channel and half turn of inlet mixture channel Swiss roll combustor. Purpose of keeping exhaust channel length more than the inlet mixture channel to ensure sufficient time for heat exchange between burned and unburned gases, which is not reported in earlier studies. Experimental study mentions effects of different design parameters like materials of combustor, various depths, equivalence ratio, mass flow rates of liquefied petroleum gas (LPG), volume of combustion space and environmental conditions (with insulation and without insulation to combustors) on fuel lean limit and fuel rich limit, temperature profile obtained on all external surfaces, in the main combustion chamber, in the channel carrying unburned gas mixture and burned gas mixture, heat loss to atmosphere from all the walls of combustor, flame location. Different combustor materials tested were stainless steel, Aluminum, copper, brass, bronze, Granite. Depths considered were 22mm, 15mm, 10mm and 5mm. It was observed that flame stability inside the combustion chamber is affected by materials, depths and flow rates. Unburned mixture carrying channel was kept below quenching distance of flame to avoid flash back. Burned gas carrying channel dimension was more than the quenching distance. Considerable temperature rise was observed with insulation to combustors. But combustors with more thermal conductivity showed more heat loss to atmosphere which led to instability of flame.

Lean NOx Trap Catalysis for Lean Natural Gas Engine Applications

DOE Office of Scientific and Technical Information (OSTI.GOV)

Parks, II, James E; Storey, John Morse; Theiss, Timothy J

Distributed energy is an approach for meeting energy needs that has several advantages. Distributed energy improves energy security during natural disasters or terrorist actions, improves transmission grid reliability by reducing grid load, and enhances power quality through voltage support and reactive power. In addition, distributed energy can be efficient since transmission losses are minimized. One prime mover for distributed energy is the natural gas reciprocating engine generator set. Natural gas reciprocating engines are flexible and scalable solutions for many distributed energy needs. The engines can be run continuously or occasionally as peak demand requires, and their operation and maintenance ismore » straightforward. Furthermore, system efficiencies can be maximized when natural gas reciprocating engines are combined with thermal energy recovery for cooling, heating, and power applications. Expansion of natural gas reciprocating engines for distributed energy is dependent on several factors, but two prominent factors are efficiency and emissions. Efficiencies must be high enough to enable low operating costs, and emissions must be low enough to permit significant operation hours, especially in non-attainment areas where emissions are stringently regulated. To address these issues the U.S. Department of Energy and the California Energy Commission launched research and development programs called Advanced Reciprocating Engine Systems (ARES) and Advanced Reciprocating Internal Combustion Engines (ARICE), respectively. Fuel efficiency and low emissions are two primary goals of these programs. The work presented here was funded by the ARES program and, thus, addresses the ARES 2010 goals of 50% thermal efficiency (fuel efficiency) and <0.1 g/bhp-hr emissions of oxides of nitrogen (NOx). A summary of the goals for the ARES program is given in Table 1-1. ARICE 2007 goals are 45% thermal efficiency and <0.015 g/bhp-hr NOx. Several approaches for improving the efficiency and emissions of natural gas reciprocating engines are being pursued. Approaches include: stoichiometric engine operation with exhaust gas recirculation and three-way catalysis, advanced combustion modes such as homogeneous charge compression ignition, and extension of the lean combustion limit with advanced ignition concepts and/or hydrogen mixing. The research presented here addresses the technical approach of combining efficient lean spark-ignited natural gas combustion with low emissions obtained from a lean NOx trap catalyst aftertreatment system. This approach can be applied to current lean engine technology or advanced lean engines that may result from related efforts in lean limit extension. Furthermore, the lean NOx trap technology has synergy with hydrogen-assisted lean limit extension since hydrogen is produced from natural gas during the lean NOx trap catalyst system process. The approach is also applicable to other lean engines such as diesel engines, natural gas turbines, and lean gasoline engines; other research activities have focused on those applications. Some commercialization of the technology has occurred for automotive applications (both diesel and lean gasoline engine vehicles) and natural gas turbines for stationary power. The research here specifically addresses barriers to commercialization of the technology for large lean natural gas reciprocating engines for stationary power. The report presented here is a comprehensive collection of research conducted by Oak Ridge National Laboratory (ORNL) on lean NOx trap catalysis for lean natural gas reciprocating engines. The research was performed in the Department of Energy's ARES program from 2003 to 2007 and covers several aspects of the technology. All studies were conducted at ORNL on a Cummins C8.3G+ natural gas engine chosen based on industry input to simulate large lean natural gas engines. Specific technical areas addressed by the research include: NOx reduction efficiency, partial oxidation and reforming chemistry, and the effects of sulfur poisons on the partial oxidation, reformer, and lean NOx trap catalysts. The initial work on NOx reduction efficiency demonstrated that NOx emissions <0.1 g/bhp-hr (the ARES goal) can be achieved with the lean NOx trap catalyst technology. Subsequent work focused on cost and size optimization and durability issues which addressed two specific ARES areas of interest to industry ('Cost of Power' and 'Availability, Reliability, and Maintainability', respectively). Thus, the research addressed the approach of the lean NOx trap catalyst technology toward the ARES goals as shown in Table 1-1.« less

Upper arm anthropometrics versus DXA scan in survivors of acute respiratory distress syndrome.

PubMed

Chan, Kitty S; Mourtzakis, Marina; Aronson Friedman, Lisa; Dinglas, Victor D; Hough, Catherine L; Ely, E Wesley; Morris, Peter E; Hopkins, Ramona O; Needham, Dale M

2018-04-01

Survivors of acute respiratory distress syndrome (ARDS) experience severe muscle wasting. Upper arm anthropometrics can provide a quick, non-invasive estimate of muscle status, but its accuracy is unknown. This study examines the accuracy of upper arm percent muscle area (UAMA) with reference measures of lean mass from dual energy X-ray absorptiometry (DXA). Data are from 120 ARDS survivors participating in a multicenter national study. Receiver operating characteristic (ROC) curves, by patient sex, demonstrated that UAMA did no better than chance in discriminating low appendicular skeletal muscle mass identified using DXA findings (c-statistics, 6 months: 0.50-0.59, 12 months: 0.54-0.57). Modest correlations of UAMA with DXA measures (whole-body: r = 0.46-0.49, arm-specific: r = 0.50-0.51, p < 0.001) and Bland-Altman plots indicate poor precision. UAMA is not an appropriate screening measure for estimating muscle mass when compared to a DXA reference standard. Alternate screening measures should be evaluated in ARDS survivors.

Integrated Solvent Design for CO 2 Capture and Viscosity Tuning

DOE PAGES

Cantu, David C.; Malhotra, Deepika; Koech, Phillip K.; ...

2017-08-18

We present novel design strategies for reduced viscosity single-component, water-lean CO 2 capture organic solvent systems. Through molecular simulation, we identify the main molecular-level descriptor that influences bulk solvent viscosity. Upon loading, a zwitterionic structure forms with a small activation energy of ca 16 kJ/mol and a small stabilization of ca 6 kJ/mol. Viscosity increases exponentially with CO 2 loading due to hydrogen-bonding between neighboring Zwitterions. We find that molecular structures that promote internal hydrogen bonding (within the same molecule) and suppress interactions with neighboring molecules have low viscosities. In addition, tuning the acid/base properties leads to a shift ofmore » the equilibrium toward a non-charged (acid) form that further reduces the viscosity. Here, based on the above structural criteria, a reduced order model is also presented that allows for the quick screening of large compound libraries and down selection of promising candidates for synthesis and testing.« less

A CFD Study of Jet Mixing in Reduced Flow Areas for Lower Combustor Emissions

NASA Technical Reports Server (NTRS)

Smith, C. E.; Talpallikar, M. V.; Holdeman, J. D.

1991-01-01

The Rich-burn/Quick-mix/Lean-burn (RQL) combustor has the potential of significantly reducing NO(x) emissions in combustion chambers of High Speed Civil Transport aircraft. Previous work on RQL combustors for industrial applications suggested the benefit of necking down the mixing section. A 3-D numerical investigation was performed to study the effects of neckdown on NO(x) emissions and to develop a correlation for optimum mixing designs in terms of neckdown area ratio. The results of the study showed that jet mixing in reduced flow areas does not enhance mixing, but does decrease residence time at high flame temperatures, thus reducing NO(x) formation. By necking down the mixing flow area by 4, a potential NO(x) reduction of 16:1 is possible for annual combustors. However, there is a penalty that accompanies the mixing neckdown: reduced pressure drop across the combustor swirler. At conventional combustor loading parameters, the pressure drop penalty does not appear to be excessive.

Comparison of Mixing Calculations for Reacting and Non-Reacting Flows in a Cylindrical Duct

NASA Technical Reports Server (NTRS)

Oechsle, V. L.; Mongia, H. C.; Holdeman, J. D.

1994-01-01

A production 3-D elliptic flow code has been used to calculate non-reacting and reacting flow fields in an experimental mixing section relevant to a rich burn/quick mix/lean burn (RQL) combustion system. A number of test cases have been run to assess the effects of the variation in the number of orifices, mass flow ratio, and rich-zone equivalence ratio on the flow field and mixing rates. The calculated normalized temperature profiles for the non-reacting flow field agree qualitatively well with the normalized conserved variable isopleths for the reacting flow field indicating that non-reacting mixing experiments are appropriate for screening and ranking potential rapid mixing concepts. For a given set of jet momentum-flux ratio, mass flow ratio, and density ratio (J, MR, and DR), the reacting flow calculations show a reduced level of mixing compared to the non-reacting cases. In addition, the rich-zone equivalence ratio has noticeable effect on the mixing flow characteristics for reacting flows.

Accuracy of Body Mass Index Versus Lean Mass Index for Prediction of Sarcopenia in Older Women.

PubMed

Benton, M J; Silva-Smith, A L

2018-01-01

We compared accuracy of body mass index (BMI) versus lean mass index (LMI) to predict sarcopenia in 58 community-dwelling women (74.1±0.9 years). Lean mass was measured with multi-frequency bioelectrical impedance analysis, and strength was measured with Arm Curl test, Chair Stand test, and handgrip dynamometry. Sarcopenia was defined as low LMI. When categorized by BMI, normal women had less absolute lean mass (37.6±1.0 vs. 42.6±0.9 kg; P<0.001) and less relative lean mass (14.1±0.2 vs. 16.1±0.2 kg/m2; P<0.001) compared to overweight/obese women, but no differences in strength. When categorized by LMI, normal women had more absolute lean mass (44.0±0.7 vs. 35.7±0.7 kg; P<0.001), more relative lean mass (16.2±0.2 vs. 13.8±0.2 kg/m2; P<0.001), and greater upper body strength (16.7±0.9 vs. 14.2±0.6 arm curls; P<0.05) compared to women with low LMI. BMI failed to accurately predict low values of lean mass and strength. For clinical assessment, calculation of LMI rather than BMI is appropriate.

Stability of leaning column at Devils Tower National Monument, Wyoming

USGS Publications Warehouse

Harp, Edwin L.; Lindsay, Charles R.

2006-01-01

In response to reports from climbers that an 8-meter section (referred to as the leaning column) of the most popular climbing route on Devils Tower in northeastern Wyoming is now moving when being climbed, scientists from the U.S. Geological Survey inspected the site to determine the stability of the column and the underlying column that serves as a support pedestal. Evidence of a recent tensile spalling failure was observed on the pedestal surface immediately beneath the contact with the overlying leaning column. The spalling of a flake-shaped piece of the pedestal, probably due to the high stress concentration exerted by the weight of the leaning column along a linear contact with the pedestal, is likely causing the present movement of the leaning column. Although it is unlikely that climbers will dislodge the leaning column by their weight alone, the possibility exists that additional spalling failures may occur from the pedestal surface and further reduce the stability of the leaning column and result in its toppling. To facilitate detection of further spalling failures from the pedestal, its surface has been coated with a layer of paint. Any new failures from the pedestal could result in the leaning column toppling onto the climbing route or onto the section of the Tower trail below.

Critical Success Factors for Lean Thinking in the Application of Industrialised Building System (IBS)

NASA Astrophysics Data System (ADS)

Yunus, Riduan; Noor, Siti Rahimah Mohd; Halid Abdullah, Abd; Nagapan, Sasitharan; Hamid, Abdul Rahim Abdul; Tajudin, Saiful Azhar Ahmad; Rohani Mat Jusof, Siti

2017-08-01

Productivity in the manufacturing process of building components can be increased by optimising each advantage that is available in each activity. Identification of critical success factors (CSFs) for lean thinking in the Industrialised Building System (IBS) will be able to minimise cost and reduce time needed to complete a project. The focus of lean thinking in construction is on the production process and the client’s requirement. In developing countries such as Malaysia, the integration of lean thinking in IBS applications is still low and there is a shortage of comprehensive strategies to integrate lean thinking. As key stakeholders, feedback from contractors, manufacturers, developers and the local authority will be able to help the identification of CSFs in integrating lean thinking in IBS applications. The data was collected through a questionnaire survey and analysed quantitatively. There are 31 CSFs for lean thinking in IBS which have been identified in this study. A conceptual model was developed to assist researchers in investigating the influences of CSFs for lean thinking in IBS applications. This study will assist construction players to improvise their manufacturing process in the implementation of IBS to eliminate unnecessary activities and focus instead on significant processes without generating physical and non-physical waste.

Why Lean doesn't work for everyone.

PubMed

Kaplan, Gary S; Patterson, Sarah H; Ching, Joan M; Blackmore, C Craig

2014-12-01

Popularisation of Lean in healthcare has led to emphasis on Lean quality improvement tools in isolation, with inconsistent results. We argue that delivery of safer, more efficient, and higher quality-patient focused care requires organisational transformation of which the Lean toolkit is only one component. To successfully facilitate system transformation toward higher quality care at lower cost, Lean tools must be part of a comprehensive management system, within a supportive institutional culture, and with committed leadership. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

The Role of Lean Process Improvement in Implementation of Evidence-Based Practices in Behavioral Health Care.

PubMed

Steinfeld, Bradley; Scott, Jennifer; Vilander, Gavin; Marx, Larry; Quirk, Michael; Lindberg, Julie; Koerner, Kelly

2015-10-01

To effectively implement evidence-based practices (EBP) in behavioral health care, an organization needs to have operating structures and processes that can address core EBP implementation factors and stages. Lean, a widely used quality improvement process, can potentially address the factors crucial to successful implementation of EBP. This article provides an overview of Lean and the relationship between Lean process improvement steps, and EBP implementation models. Examples of how Lean process improvement methodologies can be used to help plan and carry out implementation of EBP in mental health delivery systems are presented along with limitations and recommendations for future research and clinical application.

Study on stabilization and quench protection of coils wound of HTS coated conductors considering quench origins - Proposal of criteria for stabilization and quench protection

NASA Astrophysics Data System (ADS)

Tsukamoto, Osami; Fujimoto, Yasutaka; Takao, Tomoaki

2014-09-01

It has been considered that HTS coils are hard to be quenched because of high quench energy due to high critical temperature and high specific heat of HTS wires. Therefore, attention to quench protection was not much paid. However, HTS coils still have possibility to be quenched during operation by mainly the following two origins, (a) presence of non-recoverable local defects in the conductors and (b) temperature rise of long part of the conductor. Actually, severe quench accidents, such as burning coils, are occurring in various places as scales of HTS increased. Purposes of this paper are to study on behaviors of normal zone and hot spot temperature of wires during quench detect/energy dump sequence and to find criteria for the stability and quench protection. In the paper, criteria are proposed for stability and quench protection of HTS coils. A criterion for the stability is that a coil can be operated stably without a quench against defects in coil windings and that for quench protection is that a coil can be safely protected from damages caused by a quench due to temperature rise of long part of coil wires. The criteria are used as design rules for HTS coils.

Effect of strength and speed of torque development on balance recovery with the ankle strategy.

PubMed

Robinovitch, Stephen N; Heller, Britta; Lui, Andrew; Cortez, Jeffrey

2002-08-01

In the event of an unexpected disturbance to balance, the ability to recover a stable upright stance should depend not only on the magnitude of torque that can be generated by contraction of muscles spanning the lower extremity joints but also on how quickly these torques can be developed. In the present study, we used a combination of experimental and mathematical models of balance recovery by sway (feet in place responses) to test this hypothesis. Twenty-three young subjects participated in experiments in which they were supported in an inclined standing position by a horizontal tether and instructed to recover balance by contracting only their ankle muscles. The maximum lean angle where they could recover balance without release of the tether (static recovery limit) averaged 14.9 +/- 1.4 degrees (mean +/- SD). The maximum initial lean angle where they could recover balance after the tether was unexpectedly released and the ankles were initially relaxed (dynamic recovery limit) averaged 5.9 +/- 1.1 degrees, or 60 +/- 11% smaller than the static recovery limit. Peak ankle torque did not differ significantly between the two conditions (and averaged 116 +/- 32 Nm), indicating the strong effect on recovery ability of latencies in the onset and subsequent rates of torque generation (which averaged 99 +/- 13 ms and 372 +/- 267 N. m/s, respectively). Additional experiments indicated that dynamic recovery limits increased 11 +/- 14% with increases in the baseline ankle torques prior to release (from an average value of 31 +/- 18 to 54 +/- 24 N. m). These trends are in agreement with predictions from a computer simulation based on an inverted pendulum model, which illustrate the specific combinations of baseline ankle torque, rate of torque generation, and peak ankle torque that are required to attain target recovery limits.

Does media coverage influence public attitudes towards welfare recipients? The impact of the 2011 English riots.

PubMed

Reeves, Aaron; de Vries, Robert

2016-06-01

Following the shooting of Mark Duggan by police on 4 August 2011, there were riots in many large cities in the UK. As the rioting was widely perceived to be perpetrated by the urban poor, links were quickly made with Britain's welfare policies. In this paper, we examine whether the riots, and the subsequent media coverage, influenced attitudes toward welfare recipients. Using the British Social Attitudes survey, we use multivariate difference-in-differences regression models to compare attitudes toward welfare recipients among those interviewed before (pre-intervention: i.e. prior to 6 August) and after (post-intervention: 10 August-10 September) the riots occurred (N = 3,311). We use variation in exposure to the media coverage to test theories of media persuasion in the context of attitudes toward welfare recipients. Before the riots, there were no significant differences between newspaper readers and non-readers in their attitudes towards welfare recipients. However, after the riots, attitudes diverged. Newspaper readers became more likely than non-readers to believe that those on welfare did not really deserve help, that the unemployed could find a job if they wanted to and that those on the dole were being dishonest in claiming benefits. Although the divergence was clearest between right-leaning newspaper and non-newspaper readers, we do not a find statistically significant difference between right- and left-leaning newspapers. These results suggest that media coverage of the riots influenced attitudes towards welfare recipients; specifically, newspaper coverage of the riots increased the likelihood that readers of the print media expressed negative attitudes towards welfare recipients when compared with the rest of the population. © London School of Economics and Political Science 2016.

lean-ISD.

ERIC Educational Resources Information Center

Wallace, Guy W.

2001-01-01

Explains lean instructional systems design/development (ISD) as it relates to curriculum architecture design, based on Japan's lean production system. Discusses performance-based systems; ISD models; processes for organizational training and development; curriculum architecture to support job performance; and modular curriculum development. (LRW)

A Cultural Resources Inventory of Eastern Portions of Lake Sakakawea, North Dakota (Mercer and McLean Counties).

DTIC Science & Technology

1982-09-15

34esources Inventory of Eastern Portions of Lake Sakakawee, North Dakota (Mercer and McLean August - September 1982 Counties ) 6. PERFORMING ORG. REPORT...of Lake Sakakawea (Mercer and McLean Counties ), North Dakota, Identif ied 56 sites. The site types include: stone circles (36), stone cairn (1), linear...9 A CULTURAL RESOURCES INVENTORY OF EASTERN PORTIONS OF LAUE SAKAKAWRA, NORTH DAKOTA (MERCER AND XcLEAN COUNTIES

A healthcare Lean Six Sigma System for postanesthesia care unit workflow improvement.

PubMed

Kuo, Alex Mu-Hsing; Borycki, Elizabeth; Kushniruk, Andre; Lee, Te-Shu

2011-01-01

The aim of this article is to propose a new model called Healthcare Lean Six Sigma System that integrates Lean and Six Sigma methodologies to improve workflow in a postanesthesia care unit. The methodology of the proposed model is fully described. A postanesthesia care unit case study is also used to demonstrate the benefits of using the Healthcare Lean Six Sigma System model by combining Lean and Six Sigma methodologies together. The new model bridges the service gaps between health care providers and patients, balances the requirements of health care managers, and delivers health care services to patients by taking the benefits of the Lean speed and Six Sigma high-quality principles. The full benefits of the new model will be realized when applied at both strategic and operational levels. For further research, we will examine how the proposed model is used in different real-world case studies.

Lean manufacturing: A better way for enhancement in productivity

NASA Astrophysics Data System (ADS)

Kumar Ahir, Pankaj; Kumar Yadav, Lalit; Singh Chandrawat, Saurabh

2012-03-01

Productivity is the impact of peoples working together. Machines are merely an extended way of collective imagination and energy. Lean Manufacturing is the most used method for continues improvement of business. Organization management philosophy focusing on the reduction of wastage to improve overall customer value. "Lean" operating principles began in manufacturing environments and are known by a variety of synonyms; Lean Manufacturing, Lean Production, Toyota Production System, etc. It is commonly believed that Lean started in Japan "The notable activities in keeping the price of Ford products low is the steady restriction of the production cycle. The longer an article is in the process of manufacture and the more it is moved about, the greater is its ultimate cost." "A systematic approach to identifying and eliminating waste through continuous improvement, flowing the product at the pull of the customer in pursuit of perfection."

Individualisation of Lean Concept in Companies Dealing with Mass Production

NASA Astrophysics Data System (ADS)

Bednár, Roman

2012-12-01

The methods of lean manufacturing primarily designed for businesses dealing with serial production, are also used in other types of production. However the concept of lean production was not designed for these types of businesses, they are utilized only partially. Paper focuses on applying methods of lean concept in companies which are dealing with mass production and their options of exchange for other methods in the event of disagreement. Basis of the article is a list of lean methods with its description and its utilization in practice. The questionnaire was utilized to identify information from the practice. Based on this survey were identified the critical methods that are no longer appropriate for companies dealing with mass production. However, there are alternative methods of describing the problem. It is possible to say that companies are trying to get closer to their goal by modification of the basic concepts. And the concept of Lean Enterprise serves as a standard.

Readiness for change and job satisfaction in a case of lean management application - a comparative study.

PubMed

Lipińska-Grobelny, Agnieszka; Papieska, Ewelina

2012-09-01

This current study investigates the effect of lean management system on work attitudes of workers of two manufacturing companies. "Lean management" is a concept of work processes and human relations that determines company's productivity and profitability. Workers of two enterprises, the first one with lean production and the second one with old mass production, were compared for their readiness for change and job satisfaction (both emotional and cognitive aspect). The sample of 102 employees completed a battery of instruments such as: the Job Description Inventory by Neuberger and Allerbeck, the Job Affect Scale by Burke et al. and the Change-Readiness Scale by Kriegel and Brandt. Individuals from the lean manufacturing company were characterized by higher level of readiness for change, positive affect at work, and cognitive job satisfaction. In this approach the introduction of lean production positively affected company's human resource attitudes.

Dietary Variety and Decline in Lean Mass and Physical Performance in Community-Dwelling Older Japanese: A 4-year Follow-Up Study.

PubMed

Yokoyama, Y; Nishi, M; Murayama, H; Amano, H; Taniguchi, Y; Nofuji, Y; Narita, M; Matsuo, E; Seino, S; Kawano, Y; Shinkai, S

2017-01-01

To examine associations of dietary variety with changes in lean mass and physical performance during a 4-year period in an elderly Japanese population. Four-year prospective study. The Hatoyama Cohort Study and Kusatsu Longitudinal Study, Japan. 935 community-dwelling Japanese aged 65 years or older. Dietary variety was assessed using a 10-item food frequency questionnaire. Body composition was determined by multifrequency bioelectrical impedance analysis, and physical performance (grip strength and usual gait speed) was measured in surveys at baseline and 4 years later. Longitudinal analysis included only participants who were originally in the upper three quartiles of lean body mass, appendicular lean mass, grip strength, and usual gait speed. The outcome measures were decline in lean body mass, appendicular lean mass, grip strength, and usual gait speed, defined as a decrease to the lowest baseline quartile level at the 4-year follow-up survey. Associations of dietary variety with the outcome measures were examined by logistic regression analysis adjusted for potential confounders. In the fully adjusted model, the odds ratios for decline in grip strength and usual gait speed were 0.43 (95% confidence interval, 0.19-0.99) and 0.43 (confidence interval, 0.19-0.99), respectively, for participants in the highest category of dietary variety score as compared with those in the lowest category. Dietary variety was not significantly associated with changes in lean body mass or appendicular lean mass. Among older adults, greater dietary variety may help maintain physical performance, such as grip strength and usual gait speed, but not lean mass.

Dudrick Research Symposium 2015-Lean Tissue and Protein in Health and Disease.

PubMed

Earthman, Carrie P; Wolfe, Robert R; Heymsfield, Steven B

2017-02-01

The 2015 Dudrick Research Symposium "Lean Tissue and Protein in Health and Disease: Key Targets and Assessment Strategies" was held on February 16, 2015, at Clinical Nutrition Week in Long Beach, California. The Dudrick Symposium honors the many pivotal and innovative contributions to the development and advancement of parenteral nutrition made by Dr Stanley J. Dudrick, physician scientist, academic leader, and a founding member of the American Society for Parenteral and Enteral Nutrition. As the 2014 recipient of the Dudrick award, Dr Carrie Earthman chaired the symposium and was the first of 3 speakers, followed by Dr Robert Wolfe and Dr Steven Heymsfield. The symposium addressed the importance of lean tissue to health and response to disease and injury, as well as the many opportunities and challenges in its assessment at the bedside. Lean tissue assessment is beneficial to clinical care in chronic and acute care clinical settings, given the strong relationship between lean tissue and outcomes, including functional status. Currently available bioimpedance techniques, including the use of bioimpedance parameters, for lean tissue and nutrition status assessment were presented. The connection between protein requirements and lean tissue was discussed, highlighting the maintenance of lean tissue as one of the most important primary end points by which protein requirements can be estimated. The various tracer techniques to establish protein requirements were presented, emphasizing the importance of practical considerations in research protocols aimed to establish protein requirements. Ultrasound and other new and emerging technologies that may be used for lean tissue assessment were discussed, and areas for future research were highlighted.

The impact of lean production on musculoskeletal and psychosocial risks: an examination of sociotechnical trends over 20 years.

PubMed

Koukoulaki, Theoni

2014-03-01

This paper provides an extensive review of studies carried out in lean production environments in the last 20 years. It aims to identify the effects of lean production (negative or positive) on occupational health and related risk factors. Thirty-six studies of lean effects were accepted from the literature search and sorted by sector and type of outcome. Lean production was found to have a negative effect on health and risk factors; the most negative outcomes being found in the earliest studies in the automotive industry. However, examples of mixed and positive effects were also found in the literature. The strongest correlations of lean production with stress were found for characteristics found in Just-In-Time production that related to reduced cycle time and reduction of resources. Increased musculoskeletal risk symptoms were related to increases of work pace and lack of recovery time also found in Just-In-Time systems. An interaction model is developed to propose a pathway from lean production characteristics to musculoskeletal and psychosocial risk factors and also positive outcomes. An examination is also made of the changing focus of studies investigating the consequences of lean production over a 20-year period. Theories about the effects of lean production have evolved from a conceptualization that it is an inherently harmful management system, to a view that it can have mixed effects depending on the management style of the organization and the specific way it is implemented. Copyright © 2013 Elsevier Ltd and The Ergonomics Society. All rights reserved.

Implementation of lean thinking: one health system's journey.

PubMed

Kim, Christopher S; Spahlinger, David A; Kin, Jeanne M; Coffey, Richard J; Billi, John E

2009-08-01

Lean Thinking is a management philosophy derived from the manufacturing industry, where Toyota has long been the gold standard. Health care organizations have started to apply this approach to patient care. After initial experimentation, the University of Michigan Health System (UMHS) has adopted Lean Thinking as its uniform approach to quality improvement and is striving to become a complete Lean organization. In 2005, the senior leadership selected an initial set of projects in areas that traced the patient's journey across different care settings within our health system. Four of the projects were as follows: orthopedic surgery clinic scheduling, radiation oncology therapy, peripherally inserted central catheter (PICC) services, and coordination of care to the outpatient setting. Lean Thinking encourages service providers to focus on value as defined by the customer and the relentless elimination of waste that impedes the flow of value. A series of learning projects were conducted to test whether Lean methods would work at UMHS. The following factors were found to be key to LEAN PROJECT SUCCESS: expert guidance for initial efforts, leadership in the form of clinical champions and senior management support of the improvement work, frontline worker engagement in mapping out "current state" processes, identifying waste and designing an improved "future state," using metrics to develop and track interventions, and defining realistic project scope. As UMHS's experience applying Lean Thinking to our patient care processes has grown, so have support, enthusiasm, and expertise within the organization. UMHS's Lean Thinking system, now known as the Michigan Quality System, has emerged as the core improvement strategy.

Lean healthcare in developing countries: evidence from Brazilian hospitals.

PubMed

Costa, Luana Bonome Message; Filho, Moacir Godinho; Rentes, Antonio Freitas; Bertani, Thiago Moreno; Mardegan, Ronaldo

2017-01-01

The present study evaluates how five sectors of two Brazilian hospitals have implemented lean healthcare concepts in their operations. The main characteristics of the implementation process are analyzed in the present study: the motivational factor for implementation, implementation time, form (consultancy or internal), team (hospital and consultants), lean implementation continuity/sustainability, lean healthcare tools and methods implemented, problems/improvement opportunities, lean healthcare barriers faced during the implementation process, and critical factors that affected the implementation and the results obtained in each case. The case studies indicate that reducing patient lead times and costs and making financial improvements were the primary factors that motivated lean healthcare implementation in the hospitals studied. Several tools and methods were used in the cases studied, especially value stream mapping and DMAIC. The barriers found in both hospitals are primarily associated with the human factor. Additionally, the results obtained after implementation were analyzed and improvements in financial aspects, productivity and capacity, and lead time reduction of the analyzed sectors were observed. Further, this study also exhibited four propositions elaborated from the results obtained from the cases that highlighted barriers and challenges to lean healthcare implementation in developing countries. Two of these barriers are hospital organizational structure (and, consequently, how the senior management works with medical staff), and outsourcing hospital activities. This study also concluded that the initialization and maintenance of lean healthcare implementation rely heavily on external support because lean healthcare subject knowledge is not yet available in the healthcare organization, which represents a challenge. Copyright © 2015 John Wiley & Sons, Ltd. Copyright © 2015 John Wiley & Sons, Ltd.

Role of insulin in the hyperandrogenemia of lean women with polycystic ovary syndrome and normal insulin sensitivity.

PubMed

Baillargeon, Jean-Patrice; Carpentier, André

2007-10-01

To determine the effect of reducing insulin secretion on hyperandrogenemia in lean normoinsulinemic women with polycystic ovary syndrome (PCOS) and normal metabolic insulin sensitivity. Transversal assessment at baseline and prospective follow-up of lean PCOS group after 8 days of diazoxide, which reduces insulin secretion, and 1 month of leuprolide, which suppresses LH. Clinical research center of an academic hospital. Nine lean women (body mass index

Lean Mixture Engines Testing and Evaluation Program : Volume 3. Appendices.

DOT National Transportation Integrated Search

1975-01-01

This report is aimed at defining analytically and demonstrating experimentally the potential of the 'lean-burn concept.' Fuel consumption and emissions data are obtained on the engine dynamometer for the baseline engine, and two lean-burn configurati...

Kit para aplicar la metodología de Lean en el gobierno

EPA Pesticide Factsheets

Este Kit para comenzar a aplicar la metodología Lean (Gobierno optimizado) ofrece información para ayudar a las agencias de protección ambiental a planificar e implementar iniciativas Lean exitosas.

Lean in service industries: A literature review

NASA Astrophysics Data System (ADS)

V, Vignesh; Suresh, M.; Aramvalarthan, S.

2016-09-01

Lean service is an amalgamation of tools and practices which, if applied appropriately, would definitely improve the existing quality of operations and ensure the generation of a large amount of favourable financial and economic outcomes and improve the behaviour of the workforce. As a result, it assumes of great significance in the fiercely competitive modern world. This article presents a comprehensive bibliographic study about the various lean service practices through a variety of approaches like service improvement, manufacturing, supply chain, market and retailing approaches, etc. Thus it gives a clear view on how the lean services are implemented in various sectors and the contribution of lean service towards improving the quality in the services provided while reducing the costs.

ED becomes 'lean' and cuts LBTC, LOS times.

PubMed

2008-04-01

Lean manufacturing techniques, first developed by Toyota, can be successfully adapted to help improve processes in your ED. St. Luke's Episcopal Hospital in Houston, has used Lean to reduce median length of stay, frequency of diversions, and the percentage of patients who left before treatment was complete (LBTC). Here's why "Lean" can help improve the performance of your ED: It enables you and your staff to see things from the patient's point of view. Lean tools enable you to view the status of your department in real-time and to compare that status with your performance goals. Exercises help identify areas where your processes break down and determine the most likely solutions.

Influence of quenching agent on microstructure, properties and thermal stress of SiC{sub p}/2009 composites

DOE Office of Scientific and Technical Information (OSTI.GOV)

He, Tianbing, E-mail: tianbing_1988@sina.com

15% vol. SiC{sub p}/2009 composites prepared by powder metallurgy were quenched in room temperature water and 20% polyethylene glycol (PEG) solution respectively, then aged naturally. The influence of quenching agent on microstructure, properties and thermal stress of SiC{sub p}/2009 composites were investigated by means of scanning/transmission electron microscope, hardness and tensile test. The results showed that the number of precipitated phase in water quenched composites increased, with much finer in size and more homogeneous in distribution compared with 20% PEG quenched one. Meanwhile, the density of dislocation in composites by water quenching was also much higher. Intergranular corrosion did notmore » occur with the two quenching agents. The 20% PEG quenched composites exhibited slight lower hardness and higher electrical conductivity than that of water quenched one. The two quenched composites showed same level in tensile strength, but the yield strength of water-quenched composites was higher (8 MPa, 3%). The usage of 20% PEG reduced thermal stress and minimized warping deformation of the parts, it is a more suitable quenching agent for SiC{sub p}/2009 composites in engineering application fields. - Highlights: •SiC{sub p}/2009 composites quenched by water and 20% PEG solution were investigated. •Aging precipitation behavior of SiC{sub p}/2009 composites is sensitive to quenchant. •Influence of quenching agent on properties of SiC{sub p}/2009 composites are minimal. •Quenching with 20% PEG reduces thermal stress of SiC{sub p}/2009 composites remarkably. •20% PEG is a more suitable quenching agent for SiC{sub p}/2009 composites than water.« less

[Four awareness of clinical lean management].

PubMed

Xiong, L Z; Zhang, C F

2017-01-20

Along with changes of medical model, hospitals need to provide best outcome with lowest cost and best patient's experience rather than merely medical treatments. It is the cultivation of lean awareness to the doctors that could acquire such outcome. The healthcare lean awareness can be summarized as responsibility awareness, digitalized awareness, detail awareness, and outstanding awareness. Through the cultivation of lean awareness, humanism can immerse into the doctors'practice, which is conducive to train for the great masters of the medicine.

Organizational change through Lean Thinking.

PubMed

Tsasis, Peter; Bruce-Barrett, Cindy

2008-08-01

In production and manufacturing plants, Lean Thinking has been used to improve processes by eliminating waste and thus enhancing efficiency. In health care, Lean Thinking has emerged as a comprehensive approach towards improving processes embedded in the diagnostic, treatment and care activities of health-care organizations with cost containment results. This paper provides a case study example where Lean Thinking is not only used to improve efficiency and cost containment, but also as an approach to effective organizational change.

Medical and scientific writing: Time to go lean and mean.

PubMed

Bhardwaj, Payal; Sinha, Sudip; Yadav, Raj Kumar

2017-01-01

The Lean Six Sigma methodology for process improvements and driving efficiency is old, but lean writing was adopted late by the pharmaceutical world in terms of size of the documents. The documents were lean earlier, and then became voluminous, and now we are about to complete a full circle in this regard, i.e., coming back to the lean documents again using e-formats and hyperlinking. Furthermore, writing has become more and more precise over time. The need for this lean and mean medical and scientific writing arose from voluminous research globally, both industry and academia which are abuzz with skyrocketing regulatory and scientific submission volumes. The quantum of literature is so much that reviewers or information seekers firmly believe that going through even selected and relevant literature has become highly challenging. Considering this, there has been much insistence on downsizing the medical writing documents, which could be tempting enough to be leveraged for scientific publications as well. Here, we present the need for lean and mean medical writing, discuss this concept in relation to the pharmaceutical industry, and how to apply this to key documents. Furthermore, presented is the proposed algorithm for lean and mean clinical study reports and manuscripts. These thoughts are aligned to the recently established concept of data transparency, and can be easily achieved by web links between the protocols and clinical trial results disclosed publicly, and the corresponding manuscripts.

Lean in healthcare: the unfilled promise?

PubMed

Radnor, Zoe J; Holweg, Matthias; Waring, Justin

2012-02-01

In an effort to improve operational efficiency, healthcare services around the world have adopted process improvement methodologies from the manufacturing sector, such as Lean Production. In this paper we report on four multi-level case studies of the implementation of Lean in the English NHS. Our results show that this generally involves the application of specific Lean 'tools', such as 'kaizen blitz' and 'rapid improvement events', which tend to produce small-scale and localised productivity gains. Although this suggests that Lean might not currently deliver the efficiency improvements desired in policy, the evolution of Lean in the manufacturing sector also reveals this initial focus on the 'tool level'. In moving to a more system-wide approach, however, we identify significant contextual differences between healthcare and manufacturing that result in two critical breaches of the assumptions behind Lean. First, the customer and commissioner in the private sector are the one and the same, which is essential in determining 'customer value' that drives process improvement activities. Second, healthcare is predominantly designed to be capacity-led, and hence there is limited ability to influence demand or make full use of freed-up resources. What is different about this research is that these breaches can be regarded as not being primarily 'professional' in origin but actually more 'organisational' and 'managerial' and, if not addressed could severely constrain Lean's impact on healthcare productivity at the systems level. Copyright © 2011 Elsevier Ltd. All rights reserved.

Comparative study of lean practices between Japanese and Malaysia automotive service centres

NASA Astrophysics Data System (ADS)

Ahmad, Md Fauzi; Ting, Neo Yeong; Nor, Nik Hisyamudin Muhd; Wei, Chan Shiau; Hassan, Mohd Fahrul; Hamid, Nor Aziati Abdul

2017-10-01

Nowadays, lean practices are implemented in many manufacturing and services companies. Lean practices are implemented in order to minimize wastes while maximise the overall performances in an organisation. In service sector, lean practices are importance to ensure value added services can be delivered to customers. However, Malaysia automotive companies cannot compete with Japanese automotive companies in terms of their customer satisfaction. The purpose of this study is to compare the lean practice between Japanese and Malaysia automotive service centres. A total of 80 questionnaires out of 100 distributed questionnaires were responded and this represented as 80% of response rate. The Mann-Whitney test result shows that there were four out of five factors of lean practices have significant differences between Japanese and Malaysia automotive service centres, which are TPM, JIT, Kanban, and 5S. VSM has not significant difference between ownerships. In addition, TPM, JIT, Kanban, VSM and 5S were higher practices in Japanese companies against Malaysia companies. Many Malaysia companies are still in the journey of lean practices and they need recommendation guidance to compete with other long-term established companies. Based on the survey result, the significant differences are identified as weak points of Malaysia companies as an opportunity to improve. Moreover, the significance of this study can help researchers and industry players to improve lean practices in automotive service industry.

Medical and scientific writing: Time to go lean and mean

PubMed Central

Bhardwaj, Payal; Sinha, Sudip; Yadav, Raj Kumar

2017-01-01

The Lean Six Sigma methodology for process improvements and driving efficiency is old, but lean writing was adopted late by the pharmaceutical world in terms of size of the documents. The documents were lean earlier, and then became voluminous, and now we are about to complete a full circle in this regard, i.e., coming back to the lean documents again using e-formats and hyperlinking. Furthermore, writing has become more and more precise over time. The need for this lean and mean medical and scientific writing arose from voluminous research globally, both industry and academia which are abuzz with skyrocketing regulatory and scientific submission volumes. The quantum of literature is so much that reviewers or information seekers firmly believe that going through even selected and relevant literature has become highly challenging. Considering this, there has been much insistence on downsizing the medical writing documents, which could be tempting enough to be leveraged for scientific publications as well. Here, we present the need for lean and mean medical writing, discuss this concept in relation to the pharmaceutical industry, and how to apply this to key documents. Furthermore, presented is the proposed algorithm for lean and mean clinical study reports and manuscripts. These thoughts are aligned to the recently established concept of data transparency, and can be easily achieved by web links between the protocols and clinical trial results disclosed publicly, and the corresponding manuscripts. PMID:28828305

Comparison of effects of Wasabia japonica and allyl isothiocyanate on the growth of four strains of Vibrio parahaemolyticus in lean and fatty tuna meat suspensions.

PubMed

Hasegawa, N; Matsumoto, Y; Hoshino, A; Iwashita, K

1999-08-01

Lean tuna meat suspensions (LEAN), with a fat content of 0.006%, and fatty tuna meat suspension (FATTY), with a fat content of 3.0% were inoculated with four strains of Vibrio parahaemolyticus and wasabi (Wasabia japonica Matsumura) or allyl isothiocyanate (AIT) was added before incubation at 37 degrees C. During the incubation, viable Vibrio counts were determined on TCBS agar plates. Both LEAN and FATTY suspensions were inoculated with V. parahaemolyticus AOTO-81, (1.28+/-0.20) x 10(2) CFU/ml, followed by addition of 20 mg wasabi/ml, and incubation for 8 h. The viable Vibrio counts were (7.76+/-5.93) x 10(5) CFU/ml in LEAN and (3.50+/-2.65) x 10(1) CFU/ml in FATTY. When the same strain, at (1.18+/-0.22) x 10(2) CFU/ml, was incubated for 8 h with 50.9 microg AIT/ml, viable Vibrio counts were (4.79+/-1.78) x 10(4) CFU/ml in LEAN and (1.80+/-1.30) x 10(1) CFU/ml in FATTY. Growth of the other three strains with wasabi or AIT was shown to be less in FATTY than in LEAN. These results indicate that growth of V. parahaemolyticus is inhibited more in FATTY than in LEAN by wasabi and allyl isothiocyanate.

Blunted Suppression of Acyl-Ghrelin in Response to Fructose Ingestion in Obese Adolescents: the Role of Insulin Resistance

PubMed Central

Van Name, Michelle; Giannini, Cosimo; Santoro, Nicola; Jastreboff, Ania; Kubat, Jessica; Li, Fangyong; Kursawe, Romy; Savoye, Mary; Duran, Elvira; Dziura, James; Sinha, Rajita; Sherwin, Robert; Cline, Gary; Caprio, Sonia

2015-01-01

Objective Fructose consumption has risen alongside obesity and diabetes. Gut hormones involved in hunger and satiety (ghrelin and PYY) may respond differently to fructose compared to glucose ingestion. We evaluated the effects of glucose and fructose ingestion on ghrelin and PYY in lean and obese adolescents with differing insulin sensitivity. Methods Adolescents were divided into lean (n=14), obese insulin sensitive (n=12) (OIS), and obese insulin resistant (n=15) (OIR). In a double-blind, cross-over design, subjects drank 75g of glucose or fructose in random order, serum was obtained every 10 minutes for 60 minutes. Results Baseline acyl-ghrelin was highest in lean and lowest in OIR (p=0.02). After glucose ingestion acyl-ghrelin decreased similarly in lean and OIS, but appeared lower in OIR (vs lean p=0.03). Suppression differences were more pronounced after fructose (lean vs. OIS p=0.008, lean vs. OIR p<0.001). OIS became significantly hungrier after fructose (p=0.015). PYY was not significantly different at baseline, varied minimally after glucose, and rose after fructose. Conclusion Compared to lean, OIS adolescents have impaired acyl-ghrelin responses to fructose but not glucose, whereas OIR adolescents have blunted responses to both. Diminished suppression of acyl-ghrelin in childhood obesity, particularly if accompanied by insulin resistance, may promote hunger and overeating. PMID:25645909

Calculation of Glucose Dose for Intraperitoneal Glucose Tolerance Tests in Lean and Obese Mice.

PubMed

Jørgensen, Mikkel S; Tornqvist, Kristina S; Hvid, Henning

2017-01-01

Glucose tolerance tests are used frequently in nonclinical research with laboratory animals, for example during characterization of obese phenotypes. Despite published standard operating procedures for glucose tolerance tests in rodents, how glucose doses should be calculated when obese and lean animals are compared is not well documented. Typically the glucose dose is calculated as 2 g/kg body weight, regardless of body composition. With this approach, obese mice receive larger glucose doses than do lean animals, potentially leading to overestimation of glucose intolerance in obese animals. In this study, we performed intraperitoneal glucose tolerance tests in mice with diet-induced obesity and their lean controls, with glucose doses based on either the total body weight or the lean body mass of the animals. To determine glucose tolerance, we determined the blood glucose AUC during the glucose tolerance test. We found that the blood glucose AUC was increased significantly in obese mice compared with lean mice by 75% on average when glucose was dosed according to the lean body mass and by 87% when the glucose dose was calculated according to total body weight. Therefore, mice with diet-induced obesity were approximately equally glucose intolerant between the 2 dose-calculation protocols. However, we recommend calculating the glucose dose according to the lean body mass of the mice, because doing so eliminates the concern regarding overdosing of obese animals.

Quench anaylsis of MICE spectrometer superconducting solenoid

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kashikhin, Vladimir; Bross, Alan; /Fermilab

MICE superconducting spectrometer solenoids fabrication and tests are in progress now. First tests of the Spectrometer Solenoid discovered some issues which could be related to the chosen passive quench protection system. Both solenoids do not have heaters and quench propagation relied on the 'quench back' effect, cold diodes, and shunt resistors. The solenoids have very large inductances and stored energy which is 100% dissipated in the cold mass during a quench. This makes their protection a challenging task. The paper presents the quench analysis of these solenoids based on 3D FEA solution of coupled transient electromagnetic and thermal problems. Themore » simulations used the Vector Fields QUENCH code. It is shown that in some quench scenarios, the quench propagation is relatively slow and some areas can be overheated. They describe ways of improving the solenoids quench protection in order to reduce the risk of possible failure.« less

SUCCESSFUL IMPLEMENTATION OF LEAN AS A MANAGERIAL PRINCIPLE IN HEALTH CARE: A CONCEPTUAL ANALYSIS FROM SYSTEMATIC LITERATURE REVIEW.

PubMed

Maijala, Riikka; Eloranta, Sini; Reunanen, Tero; Ikonen, Tuija S

2018-01-01

The aim of this study was to identify and analyze the characteristics of leadership and management associated with a successful Lean thinking adaptation in healthcare. A systematic literature review was undertaken using electronic databases: PubMed, PubMed Systematic Review, ABI/INFORM, Business Source Complete, Emerald, JBI, and Cinahl. Inclusion criteria were: (i) a description of Lean management or leadership in health care, (ii) a reference to Lean thinking, (iii) a peer-reviewed original research article or a literature review, and (iv) a full text article available in English. Among the 1,754 peer-reviewed articles identified, nine original articles and three systematic reviews met the inclusion criteria. Data on informants, methods, and settings were extracted and collated. Content analysis was used to conduct a review of the nine original studies describing and analyzing the success factors of Lean adaptation. The characteristics of leadership and management were analyzed by using the concept of a managerial windshield that divides leadership and management into four ontological dimensions: activities, style, focus, and purpose, each with typical developmental stages of skills and capabilities. The current study has some limitations: some papers from the journals not indexed in the searched databases may have been overlooked and the literature searches were carried out only for a 5-year period. Considering the results using the windshield concept emphasizes the philosophy, principles, and tools of Lean thinking. Lean leadership and management factors in health care were mainly conceptualized as skills and capabilities such as problem solving, making changes occur, empowering, communicating, coaching, supporting, facilitating, being democratic, organizational learning, and organizational success, all of which represented middle-stage or advanced managerial skills and capabilities. A conceptual analysis of systematically reviewed studies of Lean leadership and management point to certain traits as being typical when adapting Lean thinking to health care. The concept of a managerial windshield is useful when categorizing and analyzing essential managerial skills and capabilities for Lean implementation. Findings are beneficial when learning and educating the skills required for Lean transformation in healthcare organizations.

Dietary Protein Intake and Lean Muscle Mass in Survivors of Childhood Acute Lymphoblastic Leukemia: Report From the St. Jude Lifetime Cohort Study.

PubMed

Boland, Alexandra M; Gibson, Todd M; Lu, Lu; Kaste, Sue C; DeLany, James P; Partin, Robyn E; Lanctot, Jennifer Q; Howell, Carrie R; Nelson, Heather H; Chemaitilly, Wassim; Pui, Ching-Hon; Robison, Leslie L; Mulrooney, Daniel A; Hudson, Melissa M; Ness, Kirsten K

2016-07-01

Survivors of childhood acute lymphoblastic leukemia (ALL) are at risk for low lean muscle mass and muscle weakness, which may contribute to inactivity and early development of chronic diseases typically seen in older adults. Although increasing protein intake, in combination with resistance training, improves lean muscle mass in other populations, it is not known whether muscular tissue among survivors of ALL, whose impairments are treatment-related, will respond similarly. The aim of this study was to evaluate associations among dietary protein intake, resistance training, and lean muscle mass in survivors of ALL and age-, sex-, and race-matched controls. This was a cross-sectional study. Lean muscle mass was determined with dual-energy x-ray absorptiometry, dietary information with 24-hour recalls, and participation in resistance training with a questionnaire. Participants were 365 survivors of ALL (52% male; 87% white; median age=28.5 years, range=23.6-31.7) and 365 controls with no previous cancer. Compared with controls, survivors of ALL had lower lean muscle mass (55.0 versus 57.2 kg, respectively) and lower percentage of lean muscle mass (68.6% versus 71.4%, respectively) than controls. Similar proportions of survivors (71.1%) and controls (69.7%) met recommended dietary protein intake (0.8 g/kg/d). Survivors (45.4%) were less likely to report resistance training than controls (53.8%). In adjusted models, 1-g higher protein intake per kilogram of body mass per day was associated with a 7.9% increase and resistance training ≥1×wk, with a 2.8% increase in lean muscle mass. The cross-sectional study design limits temporal evaluation of the association between protein intake and lean muscle mass. The findings suggest that survivors of childhood ALL with low lean muscle mass may benefit from optimizing dietary protein intake in combination with resistance training. Research is needed to determine whether resistance training with protein supplementation improves lean muscle mass in survivors of childhood ALL. © 2016 American Physical Therapy Association.

Elimination of waste: creation of a successful Lean colonoscopy program at an academic medical center.

PubMed

Damle, Aneel; Andrew, Nathan; Kaur, Shubjeet; Orquiola, Alan; Alavi, Karim; Steele, Scott R; Maykel, Justin

2016-07-01

Lean processes involve streamlining methods and maximizing efficiency. Well established in the manufacturing industry, they are increasingly being applied to health care. The objective of this study was to determine feasibility and effectiveness of applying Lean principles to an academic medical center colonoscopy unit. Lean process improvement involved training endoscopy personnel, observing patients, mapping the value stream, analyzing patient flow, designing and implementing new processes, and finally re-observing the process. Our primary endpoint was total colonoscopy time (minutes from check-in to discharge) with secondary endpoints of individual segment times and unit colonoscopy capacity. A total of 217 patients were included (November 2013-May 2014), with 107 pre-Lean and 110 post-Lean intervention. Pre-Lean total colonoscopy time was 134 min. After implementation of the Lean process, mean colonoscopy time decreased by 10 % to 121 min (p = 0.01). The three steps of the process affected by the Lean intervention (time to achieve adequate sedation, time to recovery, and time to discharge) decreased from 3.7 to 2.4 min (p < 0.01), 4.0 to 3.4 min (p = 0.09), and 41.2 to 35.4 min (p = 0.05), respectively. Overall, unit capacity of colonoscopies increased from 39.6 per day to 43.6. Post-Lean patient satisfaction surveys demonstrated an average score of 4.5/5.0 (n = 73) regarding waiting time, 4.9/5.0 (n = 60) regarding how favorably this experienced compared to prior colonoscopy experiences, and 4.9/5.0 (n = 74) regarding professionalism of staff. One hundred percentage of respondents (n = 69) stated they would recommend our institution to a friend for colonoscopy. With no additional utilization of resources, a single Lean process improvement cycle increased productivity and capacity of our colonoscopy unit. We expect this to result in increased patient access and revenue while maintaining patient satisfaction. We believe these results are widely generalizable to other colonoscopy units as well as other process-based interventions in health care.

Dietary Protein Intake and Lean Muscle Mass in Survivors of Childhood Acute Lymphoblastic Leukemia: Report From the St. Jude Lifetime Cohort Study

PubMed Central

Boland, Alexandra M.; Gibson, Todd M.; Lu, Lu; Kaste, Sue C.; DeLany, James P.; Partin, Robyn E.; Lanctot, Jennifer Q.; Howell, Carrie R.; Nelson, Heather H.; Chemaitilly, Wassim; Pui, Ching-Hon; Robison, Leslie L.; Mulrooney, Daniel A.; Hudson, Melissa M.

2016-01-01

Background Survivors of childhood acute lymphoblastic leukemia (ALL) are at risk for low lean muscle mass and muscle weakness, which may contribute to inactivity and early development of chronic diseases typically seen in older adults. Although increasing protein intake, in combination with resistance training, improves lean muscle mass in other populations, it is not known whether muscular tissue among survivors of ALL, whose impairments are treatment-related, will respond similarly. Objective The aim of this study was to evaluate associations among dietary protein intake, resistance training, and lean muscle mass in survivors of ALL and age-, sex-, and race-matched controls. Design This was a cross-sectional study. Methods Lean muscle mass was determined with dual-energy x-ray absorptiometry, dietary information with 24-hour recalls, and participation in resistance training with a questionnaire. Participants were 365 survivors of ALL (52% male; 87% white; median age=28.5 years, range=23.6–31.7) and 365 controls with no previous cancer. Results Compared with controls, survivors of ALL had lower lean muscle mass (55.0 versus 57.2 kg, respectively) and lower percentage of lean muscle mass (68.6% versus 71.4%, respectively) than controls. Similar proportions of survivors (71.1%) and controls (69.7%) met recommended dietary protein intake (0.8 g/kg/d). Survivors (45.4%) were less likely to report resistance training than controls (53.8%). In adjusted models, 1-g higher protein intake per kilogram of body mass per day was associated with a 7.9% increase and resistance training ≥1×wk, with a 2.8% increase in lean muscle mass. Limitations The cross-sectional study design limits temporal evaluation of the association between protein intake and lean muscle mass. Conclusions The findings suggest that survivors of childhood ALL with low lean muscle mass may benefit from optimizing dietary protein intake in combination with resistance training. Research is needed to determine whether resistance training with protein supplementation improves lean muscle mass in survivors of childhood ALL. PMID:26893509

Changes in Body Composition According to Age and Sex among Young Non-Diabetic Korean Adults: The Kangbuk Samsung Health Study.

PubMed

Kim, Seul Ki; Kwon, Yu Hyun; Cho, Jung Hwan; Lee, Da Young; Park, Se Eun; Oh, Hyung Geun; Park, Cheol Young; Lee, Won Young; Oh, Ki Won; Park, Sung Woo; Rhee, Eun Jung

2017-12-01

Age-related decreases in lean mass represent a serious health problem. We aimed to analyze the risks of rapid decreases in lean mass by age and sex in relatively young Korean adults during a 4-year follow-up study. A total of 65,856 non-diabetic participants (59.5% men, mean age 39.1 years) in a health screening program were subjected to bioimpedance body composition analyses and metabolic parameter analyses at baseline and after 4 years. The participants were sub-divided according to age, and additionally to six groups by age and the degree of body weight change over the 4-year period. The actual changes in body weight, lean mass, and fat mass and the percent changes over the 4-year period were assessed. The percent change in lean mass decreased and the percent change of fat mass increased with increasing age in every age and sex group. However, the annual percent decrease in lean mass and percent increase in fat mass were significantly higher among women than among men (-0.26% vs. -0.15% and 0.34% vs. 0.42%, respectively; P<0.01). Participants who were older than 50 years and had a weight loss <-5% during the 4 years had significantly greater decreases in lean mass and smaller decreases in fat mass, compared to those who were younger than 50 years. An odds ratio analysis to determine the lowest quartile of the percent change in lean mass according to age group revealed that participants older than 60 years had a significantly increased risk of a rapid decrease in the lean mass percentage (2.081; 95% confidence interval, 1.678 to 2.581). Even in this relatively young study population, the lean mass decreased significantly with age, and the risk of a rapid decrease in lean mass was higher among women than among men. Furthermore, the elderly exhibited a significantly more rapid decrease in lean mass, compared with younger participants. Copyright © 2017 Korean Endocrine Society

Lean Mixture Engines Testing and Evaluation Program : Volume 2. Comprehensive Discussion.

DOT National Transportation Integrated Search

1975-11-01

This report is aimed at defining analytically and demonstrating experimentally the potential of the 'lean-burn concept.' Fuel consumption and emissions data are obtained on the engine dynamometer for the baseline engine, and two lean-burn configurati...

Lean Mixture Engines Testing and Evaluation Program : Volume 1. Executive Summary.

DOT National Transportation Integrated Search

1975-01-01

This report is aimed at defining analytically and demonstrating experimentally the potential of the 'lean-burn concept'. Fuel consumption and emissions data are obtained on the engine dynamometer for the baseline engine, and two lean-burn configurati...

Environmental Professional’s Guide to Lean and Six Sigma: Executive Summary

EPA Pesticide Factsheets

Introduction to the guide that describes how Lean and Six Sigma relate to the environment and provides guidance on how environmental professionals can connect with Lean and Six Sigma activities to generate better environmental and operational results.

High-pressure gas quenching in cold chambers for increased cooling capacity

DOE Office of Scientific and Technical Information (OSTI.GOV)

Segerberg, S.; Troell, E.

1996-12-31

Gas quenching for the hardening of steel parts is a lower-pollution alternative to quenching in quenchants such as oil or salt. As the surfaces of the cooled parts remain clean after gas quenching, there is no need to wash them after heat treatment, which reduces the consumption of oils and detergents. The fire risk and ventilation requirements of oil quenching are eliminated. In addition, some trials have shown that gas quenching has a positive effect on distortion, representing a saving in finishing work and thus a reduction in costs. Today, gas quenching is used almost solely in vacuum furnaces. Quenchingmore » is normally performed in the same chamber as heating, which means that besides quenching the batch, the quenching system must also remove heat from the heating elements and insulation of the furnace. Previous trials performed by IVF have shown that gas quenching with helium of ball bearing and carburizing steels (and other steels) in sizes up to 25 mm at pressures up to 20 bar in a vacuum furnace can achieve quenching rates and hardnesses similar to those achieved by hot quenching oils. This quenching performance is not, however, capable of dealing with larger sizes or lower-alloy steels. At IVF`s request, ALD Vacuum Technologies GmbH has developed a cold high-pressure gas quenching chamber that is independent of the furnace. As a result, there is no need to cool insulation or heating elements. Quenching can be carried out in the chamber at pressures of up to 40 bar for helium or up to 10 bar for nitrogen. The quenching chamber has been supplied to IVF, and has been used for experimental quenching of steel test pieces and components. Temperatures have been recorded by using some Inconel 600 test probes, {phi} 12,5 x 60 mm, with thermocouples in their centers.« less

Ambulatory Blood Pressure Monitoring in Lean, Obese and Diabetic Children and Adolescents

PubMed Central

Shikha, Deep; Singla, Montish; Walia, Rachna; Potter, Natia; Umpaichitra, Vatcharapan; Mercado, Arlene; Winer, Nathaniel

2015-01-01

Aim To determine if children and adolescents who have obesity (Ob) or type 2 diabetes (T2DM) of relatively short duration have impaired cardiovascular function compared with lean subjects using 24-hour ambulatory blood pressure as a surrogate measure of evaluation. Methods We enrolled 100 African-Caribbean subjects (45 males/55 females), mean ages 14.4-15.2 years (range 11.8-18.5 years) and Tanner stage 4.2-4.8. Mean BMI for the Ob (n = 40), T2DM (n = 39) and lean (n = 21) groups were 40.3, 34.2 and 20.8, respectively (p < 0.01, Ob and T2DM vs. lean). Mean hemoglobin A1c in lean and Ob was 5.4 and 5.5% compared to 8.8% in T2DM (p < 0.001, T2DM vs. lean and Ob). Ambulatory blood pressure was recorded every 20 min over 24 h using Spacelabs 70207. Results Mean 24-hour, daytime and nighttime systolic blood pressure was significantly higher in Ob and T2DM compared with lean subjects (mean 24-hour 117 and 120 vs. 109 mm Hg; daytime 121 and 123 vs. 113 mm Hg; and nighttime 109 and 115 vs. 101 mm Hg; p < 0.01 for all time periods). The nocturnal systolic dip in Ob and T2DM did not differ from that of lean, whereas nocturnal diastolic dip decreased significantly in Ob and T2DM compared to lean (11.5 and 10.4 vs. 20.6 mm Hg; p < 0.01). Mean pulse pressure was significantly increased in the Ob and T2DM groups compared to lean subjects (51 and 54 vs. 45 mm Hg; p < 0.01). Conclusion Adolescent Ob and T2DM groups share adverse risk factors, which may be harbingers of adult cardiovascular events. PMID:26195970

Postural Stability When Leaning from Perceived Upright

NASA Technical Reports Server (NTRS)

Vanya, Robert D.; Grounds, John F.; Wood, Scott J.

2011-01-01

The transition between quiet stance and gait requires the volitional movement of one?s center of mass (COM) toward a limit of stability (LOS). The goal of this study was to measure the effect of leaning from perceived upright on postural stability when voluntarily maintaining fixed stance positions and during perturbations of the support surface. The COM was derived from force plate data in 12 healthy subjects while standing with feet positioned so that lateral base of support was equal to foot length. For all conditions, arms were folded and subjects were instructed to lean without bending at the hips or lifting their feet. The LOS was determined during maximal voluntary leans with eyes open and closed. The COM was then displayed on a monitor located in front of the subject. Subjects were visually guided to lean toward a target position, maintain this position for 10s, return to upright, and then repeat the same targeted lean maneuver with eyes closed. Targets were randomly presented at 2? in 8 directions and between 2-6? in these same directions according to the asymmetric LOS. Subjects were then verbally guided to lean between 2? back and 4? forward prior to a perturbation of the support surface in either a forward or backward direction. The average LOS was 5.8? forward, 2.9? back, and 4.8? in left/right directions, with no significant difference between eyes open and closed. Center of pressure (COP) velocity increased as subjects maintained fixed stance positions farther from upright, with increased variability during eyes closed conditions. The time to stability and COP path length increased as subjects leaned opposite to the direction of the support surface perturbations. We conclude that postural stability is compromised as subjects lean away from perceived upright, except for perturbations that induce sway in the direction opposite the lean. The asymmetric LOS relative to perceived upright favors postural stability for COM movements in the forward direction.

Acceptance of lean redesigns in primary care: A contextual analysis.

PubMed

Hung, Dorothy; Gray, Caroline; Martinez, Meghan; Schmittdiel, Julie; Harrison, Michael I

Lean is a leading change strategy used in health care to achieve short-term efficiency and quality improvement while promising longer-term system transformation. Most research examines Lean intervention to address isolated problems, rather than to achieve broader systemic changes to care delivery. Moreover, no studies examine contextual influences on system-wide Lean implementation efforts in primary care. The aim of this study was to identify contextual factors most critical to implementing and scaling Lean redesigns across all primary care clinics in a large, ambulatory care delivery system. Over 100 interviews and focus groups were conducted with frontline physicians, clinical staff, and operational leaders. Data analysis was guided by a modified Consolidated Framework for Implementation Research (CFIR), a popular implementation science framework. On the basis of expert recommendations, the modified framework targets factors influencing the implementation of process redesigns. This modified framework, the CFIR-PR, informed our identification of contextual factors that most impacted Lean acceptance among frontline physicians and staff. Several domains identified by the CFIR-PR were critical to acceptance of Lean redesigns. Regarding the implementation process acceptance was influenced by time and intensity of exposure to changes, "top-down" versus "bottom-up" implementation styles, and degrees of employee engagement in developing new workflows. Important factors in the inner setting were the clinic's culture and style of leadership, along with availability of information about Lean's effectiveness. Last, implementation efforts were impacted by individual and team characteristics regarding changed work roles and related issues of professional identity, authority, and autonomy. This study underscores the need for change leaders to consider the contextual factors that surround efforts to implement Lean in primary care. As Lean redesigns are scaled across a system, special attention is warranted with respect to the implementation approach, internal clinic setting, and implications for professional roles and identities of physicians and staff.

Systematic review with meta-analysis: the significance of histological disease severity in lean patients with nonalcoholic fatty liver disease.

PubMed

Sookoian, S; Pirola, C J

2018-01-01

Current evidence suggests that lean and obese patients with nonalcoholic fatty liver disease (NAFLD) share an altered metabolic and cardiovascular profile. However, there is an incomplete understanding of the natural history of "lean-NAFLD." Indeed, an unanswered question is whether lean (BMI ≤ 25 Kg/m 2 ) NAFLD-patients are protected from severe histological outcomes. To perform a meta-analysis with the goal of providing a quantitative estimation of the magnitude of fibrosis, as well as histological features associated with the disease severity, in lean versus overweight/obese-NAFLD patients. Through a systematic search up to July 2017, we identified eight studies that compared histological outcomes in lean (n = 493) versus overweight/obese (n = 2209) patients. Relative to lean-NAFLD, overweight/obese-NAFLD patients showed significantly (P = .032) higher fibrosis scores; the observed difference in means between the two groups, which is the absolute difference between the mean value of fibrosis score [0-4] ± standard error, was 0.28 ± 0.13. The risk of having nonalcoholic steatohepatitis-NASH (OR 0.58 95% CI 0.34-0.97) was significantly lower in lean-NAFLD (n = 322) than in overweight/obese-NAFLD (n = 1357), P = .04. Relative to lean-NAFLD, overweight/obese-NAFLD patients also have significantly greater NAFLD activity (difference in means ± SE: 0.58 ± 0.16, P = .0004) and steatosis (difference in means ± SE: 0.23 ± 0.07, P = .002) scores. Lean-NAFLD patients tend to show less severe histological features as compared to overweight/obese-NAFLD patients. Subsequent longitudinal assessment is needed to understand the clinical impact of these findings; however, the significant ~ 25% increment of mean fibrosis score in overweight/obese patients suggests that obesity could predict a worse long-term prognosis. © 2017 John Wiley & Sons Ltd.

Insulin-induced capillary recruitment is impaired in both lean and obese women with PCOS.

PubMed

Ketel, I J G; Serné, E H; Ijzerman, R G; Korsen, T J M; Twisk, J W; Hompes, P G A; Smulders, Y M; Homburg, R; Vorstermans, L; Stehouwer, C D A; Lambalk, C B

2011-11-01

Insulin resistance, i.e. impaired insulin-mediated glucose uptake (IMGU), is a major risk factor for type 2 diabetes in women with polycystic ovary syndrome (PCOS). Insulin-induced capillary recruitment (IICR) is considered a significant determinant of IMGU. We investigated whether IICR is a determinant IMGU in obese and lean women with and without PCOS. The study included 36 women with PCOS (20 lean, BMI 21.9 ± 2.3 kg/m(2) and 16 obese, BMI 35.9 ± 6.0 kg/m(2)) and 27 age-matched healthy controls (14 lean, BMI 22.2 ± 1.8 kg/m(2) and 13 obese, BMI 40.5 ± 7.0 kg/m(2)). IICR was evaluated by capillary microscopy during an isoglycemic-hyperinsulinemic clamp. IMGU was expressed as M/I value. The M/I value was significantly lower in obese PCOS women compared with obese controls [0.5 (0.2-1.1) versus 0.8 (0.3-1.4) (mg kg(-1) min(-1) pmol l(-1)) × 100, P < 0.01], whereas the small difference between lean PCOS and lean control women was non-significant [1.5 (0.5-2.6) versus 1.7 (1.0-3.7) (mg kg(-1) min(-1) pmol l(-1)) × 100, P = 0.17]. Hyperinsulinemia increased capillary recruitment in lean controls (53.5 ± 20.3 versus 64.9 ± 27.4 n/mm(2), P < 0.05), but not in either PCOS group nor in obese controls. IICR and androgens were a determinant of M/I value only in lean women with or without PCOS. PCOS per se is associated with impaired IICR. Obese women with PCOS, in part independent of obesity, demonstrated a profound insulin resistance, whereas the difference between lean PCOS women and healthy controls was small and statistically non-significant. IICR was a determinant of IMGU in lean, but not in obese, women regardless of the presence of PCOS.

Implementing a Lean Management System in Primary Care: Facilitators and Barriers From the Front Lines.

PubMed

Hung, Dorothy; Martinez, Meghan; Yakir, Maayan; Gray, Caroline

2015-01-01

Although Lean management techniques are increasingly used in health care to improve quality and reduce costs, lessons about how to successfully implement this approach on the front lines of care delivery are not well documented. In this study, we highlight key facilitators and barriers to implementing Lean among frontline primary care providers. This case study took place at a large, ambulatory care delivery system serving nearly 1 million patients. In-depth interviews were conducted with primary care physicians, staff, and administrators to identify key factors impacting Lean redesigns in primary care. Overall, staff engagement and performance management, sensitivity to the professional values and culture of medicine, and perceived adequacy of organizational resources were critical when introducing Lean changes. Specific drivers of change included empowerment of staff at all levels, visual display of performance metrics, and a culture of innovation and collaboration. Barriers included physician resistance to standardized work, difficulty transferring management responsibilities to non-physician staff, and time and staffing required for participating in improvement efforts. Although Lean offers a new approach to delivering care, the implementation process itself is both complex and crucial to success. Understanding early facilitators and barriers can maximize Lean's, potential to improve health care delivery.

β cell function and insulin resistance in lean cases with polycystic ovary syndrome.

PubMed

Pande, Arunkumar R; Guleria, Ashwani Kumar; Singh, Sudhanshu Dev; Shukla, Manoj; Dabadghao, Preeti

2017-11-01

Obesity is a major factor in development of insulin resistance (IR) and metabolic features in polycystic ovary syndrome (PCOS) patients. Nearly two-thirds patients with PCOS (30 of 37 confirmed cases of PCOS) in our previous community based study were lean, in contrast to Caucasians. Metabolic parameters including IR and β cell function have not been characterized well in this group of lean PCOS. To study the metabolic features including IR and β cell function in lean PCOS patients, 53 patients with BMI, <23 kg/m 2 were compared with 71 obese PCOS and 45 age and body mass index matched controls. Lean patients had similar β cell function and IR as compared to controls and obese patients, though the latter group had more metabolic abnormality. Fasting c-peptide and its ratio to glucose were significantly higher in lean patients compared to controls. In subset of subjects with five point OGTT, disposition index and Matsuda index (MI) showed significant negative correlation with BMI and blood pressure. MI also negatively correlated with waist, WHR, and HOMAB. High fasting C-peptide is probably a class effect as is seen in both lean and obese PCOS.

A fuzzy model for achieving lean attributes for competitive advantages development using AHP-QFD-PROMETHEE

NASA Astrophysics Data System (ADS)

Roghanian, E.; Alipour, Mohammad

2014-06-01

Lean production has become an integral part of the manufacturing landscape as its link with superior performance and its ability to provide competitive advantage is well accepted among academics and practitioners. Lean production helps producers in overcoming the challenges organizations face through using powerful tools and enablers. However, most companies are faced with restricted resources such as financial and human resources, time, etc., in using these enablers, and are not capable of implementing all these techniques. Therefore, identifying and selecting the most appropriate and efficient tool can be a significant challenge for many companies. Hence, this literature seeks to combine competitive advantages, lean attributes, and lean enablers to determine the most appropriate enablers for improvement of lean attributes. Quality function deployment in fuzzy environment and house of quality matrix are implemented. Throughout the methodology, fuzzy logic is the basis for translating linguistic judgments required for the relationships and correlation matrix to numerical values. Moreover, for final ranking of lean enablers, a multi-criteria decision-making method (PROMETHEE) is adopted. Finally, a case study in automotive industry is presented to illustrate the implementation of the proposed methodology.

Mechanisms of lower maintenance dose of tacrolimus in obese patients.

PubMed

Sawamoto, Kazuki; Huong, Tran T; Sugimoto, Natsumi; Mizutani, Yuka; Sai, Yoshimichi; Miyamoto, Ken-ichi

2014-01-01

A retrospective analysis suggested that blood tacrolimus concentrations were consistent among patients with a body mass index (BMI) that was lean (<18.5), normal (≥ 18.5 and <25) or overweight/obese (≥ 25). The average maintenance dose of tacrolimus in patients with BMI ≥ 25 was significantly lower compared with that in patients with a BMI of less than 25. Lean and obese Zucker rats fed a normal diet were given tacrolimus intravenously or orally. The blood concentrations of tacrolimus in obese rats were significantly higher than those in lean rats after administration via both routes. The moment analysis has suggested that CLtot and Vdss of tacrolimus were not significantly different between lean and obese rats. The bioavailability was higher in obese rats, compared with that in lean rats. The protein expression of Cyp3a2 in the liver was significantly decreased in obese rats, compared with lean rats, while P-gp in the small intestine was also significantly decreased in obese rats. These results suggested that the steady-state trough concentration of tacrolimus in obese patients was well maintained by a relatively low dose compared with that in normal and lean patients, presumably due to increased bioavailability.

Lean methodology: supporting battlefield medical fitness by cutting process waste.

PubMed

Huggins, Elaine J

2010-01-01

Healthcare has long looked at decreasing risk in communication and patient care processes. Increasing the simplicity in communication and patient care process is a newer concept contained in Lean methodology. Lean is a strategy for achieving improvement in performance through the elimination of steps that use resources without contributing to customer value. This is known as cutting waste or nonvalue added steps. This article outlines how the use of Lean improved a key process that supports battlefield medical fitness.

The Effect of Special Operations Training on Testosterone, Lean Body Mass, and Strength and the Potential for Therapeutic Testosterone Replacement: A Review of the Literature

DTIC Science & Technology

2016-07-01

Effects of Testosterone or Anabolic Androgenic Steroid on Body Mass, Lean Body Mass, and Strength in Patients with Disease or Muscle Wasting...of Ranger training reportedly decreased body mass, fat mass, and lean body mass (LBM), with reductions in field measures of strength and power of...Table 3. Effects of Testosterone or Anabolic Androgenic Steroid with Resistance Training on Lean Body Mass and Strength Source Subjects Treatment

Use of leaning vanes in a two stage fan

NASA Technical Reports Server (NTRS)

Rao, G. V. R.; Digumarthi, R. V.

1975-01-01

The use of leaning vanes for tone noise reduction was examined in terms of their application in a typical two-stage high pressure ratio fan. In particular for stages designed with outlet guide vanes and zero swirl between stages, leaning the vanes of the first stage stator was studied, since increasing the number of vanes and the gap between stages do not provide the desired advantage. It was shown that noise reduction at higher harmonics of blade passing frequency can be obtained by leaning the vanes.

Influence of diet, exercise and serum vitamin D on sarcopenia in post-menopausal women

PubMed Central

Mason, Caitlin; Xiao, Liren; Imayama, Ikuyo; Duggan, Catherine R.; Foster-Schubert, Karen E.; Kong, Angela; Campbell, Kristin L.; Wang, Ching-Yun; Villasenor, Adriana; Neuhouser, Marian L.; Alfano, Catherine M.; Blackburn, George L.; McTiernan, Anne

2012-01-01

Purpose To investigate the effects of 12 months of dietary weight loss and/or aerobic exercise on lean mass and the measurements defining sarcopenia in postmenopausal women, and to examine the potential moderating effect of serum 25-hydroxyvitamin D (25(OH)D) and age. Methods 439 overweight and obese postmenopausal women were randomized to: diet modification (N=118); exercise (N=117), diet+exercise (N=117), or control (N=87). The diet intervention was a group-based program with a 10% weight loss goal. The exercise intervention was 45 mins/day, 5 days/week of moderate-to-vigorous intensity aerobic activity. Total and appendicular lean mass were quantified by dual Xray absorptiometry (DXA) at baseline and 12 months. A skeletal muscle index (SMI=appendicular lean mass (kg)/m2) and the prevalence of sarcopenia (SMI<5.67 kg/m2) were calculated. Serum 25(OH)D was assayed using a competitive chemiluminescent immunoassay. Results Dietary weight loss resulted in a significant decrease in lean mass, and a borderline significant decrease in appendicular lean mass and SMI compared to controls. In contrast, aerobic exercise significantly preserved appendicular lean mass and SMI. Diet + exercise attenuated the loss of appendicular lean mass and SMI compared to diet alone, and did not result in significant loss of total- or appendicular lean mass compared to controls. Neither serum 25(OH)D nor age were significant moderators of the intervention effects. Conclusions Aerobic exercise added to dietary weight loss can attenuate the loss of appendicular lean mass during weight loss, and may be effective for the prevention and treatment of sarcopenia among overweight and obese postmenopausal women. PMID:23190588

Nutritional Status of Maintenance Dialysis Patients: Low Lean Body Mass Index and Obesity Are Common, Protein-Energy Wasting Is Uncommon.

PubMed

Koefoed, Mette; Kromann, Charles Boy; Juliussen, Sophie Ryberg; Hvidtfeldt, Danni; Ekelund, Bo; Frandsen, Niels Erik; Marckmann, Peter

2016-01-01

Maintenance dialysis patients are at increased risk of abnormal nutritional status due to numerous causative factors, both nutritional and non-nutritional. The present study assessed the current prevalence of protein-energy wasting, low lean body mass index and obesity in maintenance dialysis patients, and compared different methods of nutritional assessment. In a cross-sectional study conducted in 2014 at Roskilde Hospital, Denmark, we performed anthropometry (body weight, skinfolds, mid-arm, waist, and hip circumferences), and determined plasma albumin and normalized protein catabolic rate in order to assess the prevalence of protein-energy wasting, low lean body mass index and obesity in these patients. Seventy-nine eligible maintenance dialysis patients participated. The prevalence of protein-energy wasted patients was 4% (95% CI: 2-12) as assessed by the coexistence of low lean body mass index and low fat mass index. Low lean body mass index was seen in 32% (95% CI: 22-44). Obesity prevalence as assessed from fat mass index was 43% (95% CI: 32-55). Coexistence of low lean body mass index and obesity was seen in 10% (95% CI: 5-19). The prevalence of protein-energy wasting and obesity varied considerably, depending on nutritional assessment methodology. Our data indicate that protein-energy wasting is uncommon, whereas low lean body mass index and obesity are frequent conditions among patients in maintenance dialysis. A focus on how to increase and preserve lean body mass in dialysis patients is suggested in the future. In order to clearly distinguish between shortage, sufficiency and abundance of protein and/or fat deposits in maintenance dialysis patients, we suggest the simple measurements of lean body mass index and fat mass index.

Effective management of patients with acute ischemic stroke based on lean production on thrombolytic flow optimization.

PubMed

Liang, Zhuoyuan; Ren, Lijie; Wang, Ting; Hu, Huoyou; Li, Weiping; Wang, Yaping; Liu, Dehong; Lie, Yi

2016-12-01

The efficacy of thrombolytic therapy for acute ischemic stroke (AIS) decreases when the administration of tissue plasminogen activator (tPA) is delayed. Derived from Toyota Production System, lean production aims to create top-quality products with high-efficiency procedures, a concept that easily applies to emergency medicine. In this study, we aimed to determine whether applying lean principles to flow optimization could hasten the initiation of thrombolysis. A multidisciplinary team (Stroke Team) was organized to implement an ongoing, continuous loop of lean production that contained the following steps: decomposition, recognition, intervention, reengineering and assessment. The door-to-needle time (DNT) and the percentage of patients with DNT ≤ 60 min before and after the adoption of lean principles were used to evaluate the efficiency of our flow optimization. Thirteen patients with AIS in the pre-lean period and 43 patients with AIS in the lean period (23 in lean period I and 20 patients in lean period II) were consecutively enrolled in our study. After flow optimization, we reduced DNT from 90 to 47 min (p < 0.001 ¤ ). In addition, the percentage of patients treated ≤60 min after hospital arrival increased from 38.46 to 75.0 % (p = 0.015 ¤ ). Adjusted analysis of covariance confirmed a significant influence of optimization on delay of tPA administration (p < 0.001). The patients were more likely to have a good prognosis (mRS ≤ 2 at 90 days) after the flow optimization (30.77-75.00 %, p = 0.012 ¤ ). Our study may offer an effective approach for optimizing the thrombolytic flow in the management of AIS.

Relative Importance of Lean and Fat Mass on Bone Mineral Density in Iranian Children and Adolescents.

PubMed

Jeddi, Marjan; Dabbaghmanesh, Mohammad Hossein; Ranjbar Omrani, Gholamhossein; Ayatollahi, Sayed Mohammad Taghi; Bagheri, Zahra; Bakhshayeshkaram, Marzieh

2015-07-01

Body weight is made up of lean and fat mass and both are involved in growth and development. Impression of these two components in bone density accrual has been controversial. The aim of this study was to evaluate the relationship between fat and lean mass and bone density in Iranian children and adolescents. A cross-sectional study was performed on 472 subjects (235 girls, 237 boys) aged 9-18 years old in Fars Province. The participants' weight, height, waist circumference, stage of puberty, and level of physical activity were recorded. Bone Mineral Content (BMC), Bone Mineral Density (BMD), total body fat and lean mass were measured using dual-energy X-ray absorptiometry. Results showed that 12.2% of boys and 12.3% of girls were overweight and 5.5% of boys and 4.7% of girls were obese. Obese individuals had greater total body BMD (0.96 ± 0.11) than normal-weight ones (0.86 ± 0.11) (P < 0.001). We found the greatest correlation between total body BMD and total body lean mass (R = 0.78. P < 0.001) and the least correlation with total body fat percentage (R = 0.03, P = 0.44). Total lean mass in more active boys was 38.1 ± 10.9 and in less active boys was 32.3 ± 11.0 (P < 0.001). The results of multiple regression analysis showed that age and total body lean mass were independent factors of BMD in growing children and adolescents. These findings suggest that lean mass was the most important predictor of BMD in both genders. Physical activity appears to positively impact on lean mass and needs to be considered in physical education and health-enhancing programs in Iranian school children.

Lean in healthcare: A comprehensive review.

PubMed

D'Andreamatteo, Antonio; Ianni, Luca; Lega, Federico; Sargiacomo, Massimo

2015-09-01

Lean seems to be the next revolution for a better, improved, value-based healhcare. In the last 15 years Lean has been increasingly adapted and adopted in healthcare. Accordingly, Lean healthcare has been developing into a major strand of research since the early 2000s. The aim of this work is to present a comprehensive overview of the main issues highlighted by research on implementation of Lean in a complex contest such as the healthcare one. Comprehensive literature review was conducted in order to identify empirical and theoretical articles published up to September 2013. Thematic analysis was performed in order to extract and synthesis data. 243 articles were selected for analysis. Lean is best understood as a means to increase productivity. Hospital is the more explored setting, with emergency and surgery as the pioneer departments. USA appears to be the leading country for number of applications. The theoretical works have been focused mainly on barriers, challenges and success factors. Sustainability, framework for measurement and critical appraisal remain underestimated themes. Evaluations of "system wide approach" are still low in number. Even though Lean results appear to be promising, findings so far do not allow to draw a final word on its positive impacts or challenges when introduced in the healthcare sector. Scholars are called to explore further the potentiality and the weaknesses of Lean, above all as for the magnitude of investments required and for the engagement of the whole organization it represents increasingly strategic choice, whilst health professionals, managers and policy makers could and should learn from research how to play a pivotal role for a more effective implementation of lean in different health contexts. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Lower Lean Mass Measured by Dual-Energy X-ray Absorptiometry (DXA) is Not Associated with Increased Risk of Hip Fracture in Women: The Framingham Osteoporosis Study.

PubMed

McLean, Robert R; Kiel, Douglas P; Berry, Sarah D; Broe, Kerry E; Zhang, Xiaochun; Cupples, L Adrienne; Hannan, Marian T

2018-01-05

Although muscle mass influences strength in older adults, it is unclear whether low lean mass measured by dual-energy X-ray absorptiometry (DXA) is an independent risk factor for hip fracture. Our objective was to determine the association between DXA lean mass and incident hip fracture risk among 1978 women aged 50 years and older participating in the Framingham Study Original and Offspring cohorts. Leg and total body lean mass (kg) were assessed from whole-body DXA scans collected in 1992-2001. Hip fracture follow-up extended from DXA assessment to the occurrence of fracture, death, drop-out, or end of follow-up in 2007. Cox proportional hazards regression was used to calculate hazard ratios (HR) and 95% confidence intervals (CI) estimating the relative risk of hip fracture associated with a 1-kg increase in baseline lean mass. Mean age was 66 years (range 50-93). Over a median of 8 years of follow-up, 99 hip fractures occurred. In models adjusted for age, height, study cohort, and percent total body fat, neither leg (HR 1.11; 95% CI 0.94, 1.31) nor total body (HR 1.06; 95% CI 0.99, 1.13) lean mass were associated with hip fracture. After further adjustment for femoral neck bone mineral density, leg lean mass results were similar (HR 1.10; 95% CI 0.93, 1.30). In contrast, 1 kg greater total body lean mass was associated with 9% higher hip fracture risk (HR 1.09; 95% CI 1.02, 1.18). Our findings suggest that in women, lower lean mass measured by DXA is not associated with increased risk of hip fracture.

Risk for development of severe liver disease in lean patients with nonalcoholic fatty liver disease: A long-term follow-up study.

PubMed

Hagström, Hannes; Nasr, Patrik; Ekstedt, Mattias; Hammar, Ulf; Stål, Per; Hultcrantz, Rolf; Kechagias, Stergios

2018-01-01

Most patients with nonalcoholic fatty liver disease (NAFLD) are overweight or obese. However, a significant proportion of patients have a normal body mass index (BMI), denoted as lean NAFLD. The long-term prognosis of lean NAFLD is unclear. We conducted a cohort study of 646 patients with biopsy-proven NAFLD. Patients were defined as lean (BMI < 25.0), overweight (BMI 25.0-29.9), or obese (BMI ≥ 30.0) at the time of biopsy. Each case was matched for age, sex, and municipality to 10 controls. Overall mortality and development of severe liver disease were evaluated using population-based registers. Cox regression models adjusted for age, sex, type 2 diabetes, and fibrosis stage were used to examine the long-term risk of mortality and liver-related events in lean and nonlean NAFLD. Lean NAFLD was seen in 19% of patients, while 52% were overweight and 29% were obese. Patients with lean NAFLD were older, had lower transaminases, lower stages of fibrosis, and lower prevalence of nonalcoholic steatohepatitis at baseline compared to patients with a higher BMI. During a mean follow-up of 19.9 years (range 0.4-40 years) representing 12,631 person years and compared to patients who were overweight, patients with lean NAFLD had no increased risk for overall mortality (hazard ratio 1.06; P =  0.73) while an increased risk for development of severe liver disease was found (hazard ratio 2.69; P =  0.007). Conclusion : Although patients with lean NAFLD have lower stages of fibrosis, they are at higher risk for development of severe liver disease compared to patients with NAFLD and a higher BMI, independent of available confounders. ( Hepatology Communications 2018;2:48-57).

Cutpoints for Low Appendicular Lean Mass That Identify Older Adults With Clinically Significant Weakness

PubMed Central

Peters, Katherine W.; Shardell, Michelle D.; McLean, Robert R.; Dam, Thuy-Tien L.; Kenny, Anne M.; Fragala, Maren S.; Harris, Tamara B.; Kiel, Douglas P.; Guralnik, Jack M.; Ferrucci, Luigi; Kritchevsky, Stephen B.; Vassileva, Maria T.; Studenski, Stephanie A.; Alley, Dawn E.

2014-01-01

Background. Low lean mass is potentially clinically important in older persons, but criteria have not been empirically validated. As part of the FNIH (Foundation for the National Institutes of Health) Sarcopenia Project, this analysis sought to identify cutpoints in lean mass by dual-energy x-ray absorptiometry that discriminate the presence or absence of weakness (defined in a previous report in the series as grip strength <26kg in men and <16kg in women). Methods. In pooled cross-sectional data stratified by sex (7,582 men and 3,688 women), classification and regression tree (CART) analysis was used to derive cutpoints for appendicular lean body mass (ALM) that best discriminated the presence or absence of weakness. Mixed-effects logistic regression was used to quantify the strength of the association between lean mass category and weakness. Results. In primary analyses, CART models identified cutpoints for low lean mass (ALM <19.75kg in men and <15.02kg in women). Sensitivity analyses using ALM divided by body mass index (BMI: ALMBMI) identified a secondary definition (ALMBMI <0.789 in men and ALMBMI <0.512 in women). As expected, after accounting for study and age, low lean mass (compared with higher lean mass) was associated with weakness by both the primary (men, odds ratio [OR]: 6.9 [95% CI: 5.4, 8.9]; women, OR: 3.6 [95% CI: 2.9, 4.3]) and secondary definitions (men, OR: 4.3 [95% CI: 3.4, 5.5]; women, OR: 2.2 [95% CI: 1.8, 2.8]). Conclusions. ALM cutpoints derived from a large, diverse sample of older adults identified lean mass thresholds below which older adults had a higher likelihood of weakness. PMID:24737559

Nutritional Status of Maintenance Dialysis Patients: Low Lean Body Mass Index and Obesity Are Common, Protein-Energy Wasting Is Uncommon

PubMed Central

Koefoed, Mette; Kromann, Charles Boy; Juliussen, Sophie Ryberg; Hvidtfeldt, Danni; Ekelund, Bo; Frandsen, Niels Erik; Marckmann, Peter

2016-01-01

Background and Aims Maintenance dialysis patients are at increased risk of abnormal nutritional status due to numerous causative factors, both nutritional and non-nutritional. The present study assessed the current prevalence of protein-energy wasting, low lean body mass index and obesity in maintenance dialysis patients, and compared different methods of nutritional assessment. Methods In a cross-sectional study conducted in 2014 at Roskilde Hospital, Denmark, we performed anthropometry (body weight, skinfolds, mid-arm, waist, and hip circumferences), and determined plasma albumin and normalized protein catabolic rate in order to assess the prevalence of protein-energy wasting, low lean body mass index and obesity in these patients. Results Seventy-nine eligible maintenance dialysis patients participated. The prevalence of protein-energy wasted patients was 4% (95% CI: 2–12) as assessed by the coexistence of low lean body mass index and low fat mass index. Low lean body mass index was seen in 32% (95% CI: 22–44). Obesity prevalence as assessed from fat mass index was 43% (95% CI: 32–55). Coexistence of low lean body mass index and obesity was seen in 10% (95% CI: 5–19). The prevalence of protein-energy wasting and obesity varied considerably, depending on nutritional assessment methodology. Conclusions Our data indicate that protein-energy wasting is uncommon, whereas low lean body mass index and obesity are frequent conditions among patients in maintenance dialysis. A focus on how to increase and preserve lean body mass in dialysis patients is suggested in the future. In order to clearly distinguish between shortage, sufficiency and abundance of protein and/or fat deposits in maintenance dialysis patients, we suggest the simple measurements of lean body mass index and fat mass index. PMID:26919440

Effects of fasting on insulin action and glucose kinetics in lean and obese men and women.

PubMed

Bergman, Bryan C; Cornier, Marc-Andre; Horton, Tracy J; Bessesen, Daniel H

2007-10-01

The development of insulin resistance in the obese individual could impair the ability to appropriately adjust metabolism to perturbations in energy balance. We investigated a 12- vs. 48-h fast on hepatic glucose production (R(a)), peripheral glucose uptake (R(d)), and skeletal muscle insulin signaling in lean and obese subjects. Healthy lean [n = 14; age = 28.0 +/- 1.4 yr; body mass index (BMI) = 22.8 +/- 0.42] and nondiabetic obese (n = 11; age = 34.6 +/- 2.3 yr; BMI = 36.1 +/- 1.5) subjects were studied following a 12- and 48-h fast during 2 h of rest and a 3-h 40 mUxm(-2)xmin(-1) hyperinsulinemic-euglycemic clamp (HEC). Basal glucose R(a) decreased significantly from the 12- to 48-h fast (lean 1.96 +/- 0.23 to 1.63 +/- 0.15; obese 1.23 +/- 0.07 to 1.07 +/- 0.07 mgxkg(-1)xmin(-1); P = 0.004) and was equally suppressed during the HEC after both fasts. The increase in glucose R(d) during the HEC after the 12-h fast was significantly decreased in lean and obese subjects after the 48-h fast (lean 9.03 +/- 1.17 to 4.16 +/- 0.34, obese 6.10 +/- 0.77 to 3.56 +/- 0.30 mgxkg FFM(-1)xmin(-1); P < 0.001). After the 12- but not the 48-h fast, insulin-stimulated AKT Ser(473) phosphorylation was greater in lean than obese subjects. We conclude that 1) 48 h of fasting produces a marked decline in peripheral insulin action, while suppression of hepatic glucose production is maintained in lean and obese men and women; and 2) the magnitude of this decline is greater in lean vs. obese subjects.

Lean Mass Asymmetry Influences Force and Power Asymmetry During Jumping in Collegiate Athletes

PubMed Central

Bell, David R.; Sanfilippo, Jennifer L.; Binkley, Neil; Heiderscheit, Bryan C.

2015-01-01

The purpose of this investigation was to: (1) examine how asymmetry in lower extremity lean mass influenced force and power asymmetry during jumping, (2) determine how power and force asymmetry affected jump height, and (3) report normative values in collegiate athletes. Force and power were assessed from each limb using bilateral force plates during a countermovement jump in 167 Division 1 athletes (mass=85.7±20.3kg, age=20.0±1.2years, 103M/64F). Lean mass of the pelvis, thigh, and shank was assessed via dual-energy X-ray absorptiometry. Percent asymmetry was calculated for lean mass at each region (pelvis, thigh, and shank) as well as force and power. Forward stepwise regressions were performed to determine the influence of lean mass asymmetry on force and power asymmetry. Thigh and shank lean mass asymmetry explained 20% of the variance in force asymmetry (R2=0.20, P<0.001), while lean mass asymmetry of the pelvis, thigh and shank explained 25% of the variance in power asymmetry (R2=0.25, P<0.001). Jump height was compared across level of force and power asymmetry (P>0.05) and greater than 10% asymmetry in power tended to decrease performance (effect size>1.0). Ninety-five percent of this population (2.5th to 97.5th percentile) displayed force asymmetry between −11.8 to 16.8% and a power asymmetry between −9.9 to 11.5%. A small percentage (<4%) of these athletes displayed more than 15% asymmetry between limbs. These results demonstrate that lean mass asymmetry in the lower extremity is at least partially responsible for asymmetries in force and power. However, a large percentage remains unexplained by lean mass asymmetry. PMID:24402449

Lean mass asymmetry influences force and power asymmetry during jumping in collegiate athletes.

PubMed

Bell, David R; Sanfilippo, Jennifer L; Binkley, Neil; Heiderscheit, Bryan C

2014-04-01

The purpose of this investigation was to (a) examine how asymmetry in lower extremity lean mass influenced force and power asymmetry during jumping, (b) determine how power and force asymmetry affected jump height, and (c) report normative values in collegiate athletes. Force and power were assessed from each limb using bilateral force plates during a countermovement jump in 167 division 1 athletes (mass = 85.7 ± 20.3 kg, age = 20.0 ± 1.2 years; 103 men and 64 women). Lean mass of the pelvis, thigh, and shank was assessed using dual-energy x-ray absorptiometry. Percent asymmetry was calculated for lean mass at each region (pelvis, thigh, and shank) as well as force and power. Forward stepwise regressions were performed to determine the influence of lean mass asymmetry on force and power asymmetry. Thigh and shank lean mass asymmetry explained 20% of the variance in force asymmetry (R = 0.20, p < 0.001), whereas lean mass asymmetry of the pelvis, thigh, and shank explained 25% of the variance in power asymmetry (R = 0.25, p < 0.001). Jump height was compared across level of force and power asymmetry (p > 0.05) and greater than 10% asymmetry in power tended to decrease the performance (effect size >1.0). Ninety-five percent of this population (2.5th to 97.5th percentile) displayed force asymmetry between -11.8 and 16.8% and a power asymmetry between -9.9 and 11.5%. A small percentage (<4%) of these athletes displayed more than 15% asymmetry between limbs. These results demonstrate that lean mass asymmetry in the lower extremity is at least partially responsible for asymmetries in force and power. However, a large percentage remains unexplained by lean mass asymmetry.

Steroid hormone profiling in obese and nonobese women with polycystic ovary syndrome.

PubMed

Deng, Yuying; Zhang, Yifei; Li, Shengxian; Zhou, Wenzhong; Ye, Lei; Wang, Lihua; Tao, Tao; Gu, Junjie; Yang, Zuwei; Zhao, Dandan; Gu, Weiqiong; Hong, Jie; Ning, Guang; Liu, Wei; Wang, Weiqing

2017-10-26

The study explored differences in the steroidogenic pathway between obese and nonobese women with polycystic ovary syndrome (PCOS) using liquid chromatography-tandem mass spectrometry (LC-MS/MS). 1044 women with PCOS (including 350 lean, 312 overweight and 382 obese) and 366 control women without PCOS (including 203 lean, 32 overweight and 131 obese) were enrolled. The differences in steroid hormones were amplified in lean PCOS versus lean controls compared with obese PCOS versus obese controls. Compared with obese PCOS, lean PCOS demonstrated increased dehydroepiandrosterone sulfate (P = 0.015), 17-hydropregnenolone (P = 0.003), 17-hydroprogesterone (17-OHP) (P < 0.001), progesterone (P < 0.001) and estrone (P < 0.001) levels. Enzyme activity evaluation showed that lean PCOS had increased activity of P450c17 (17-hydropregnenolone/pregnenolone, P < 0.001), P450aro (P < 0.001), 3βHSD2 (progesterone/ pregnenolone and 17-OHP/17-hydropregnenolone, both P < 0.001) and decreased activity of P450c21(11-deoxycorticorsterone/progesterone and 11-deoxycortisol/17-OHP, P < 0.001). Moreover, we found higher frequencies of CYP21A2- (encoding P450c21) c.552 C > G (p. D184E) in lean PCOS compared with obese PCOS patients (P = 0.006). In conclusion, this study demonstrated for the first time that the adrenal-specific enzyme P450c21 showed decreased activity in lean PCOS patients, and that the adrenal androgen excess may play different roles in lean and obese PCOS patients, which represents as different enzyme activity in the steroidogenic pathway.

Role of protein and amino acids in promoting lean mass accretion with resistance exercise and attenuating lean mass loss during energy deficit in humans.

PubMed

Churchward-Venne, Tyler A; Murphy, Caoileann H; Longland, Thomas M; Phillips, Stuart M

2013-08-01

Amino acids are major nutrient regulators of muscle protein turnover. After protein ingestion, hyperaminoacidemia stimulates increased rates of skeletal muscle protein synthesis, suppresses muscle protein breakdown, and promotes net muscle protein accretion for several hours. These acute observations form the basis for strategized protein intake to promote lean mass accretion, or prevent lean mass loss over the long term. However, factors such as protein dose, protein source, and timing of intake are important in mediating the anabolic effects of amino acids on skeletal muscle and must be considered within the context of evaluating the reported efficacy of long-term studies investigating protein supplementation as part of a dietary strategy to promote lean mass accretion and/or prevent lean mass loss. Current research suggests that dietary protein supplementation can augment resistance exercise-mediated gains in skeletal muscle mass and strength and can preserve skeletal muscle mass during periods of diet-induced energy restriction. Perhaps less appreciated, protein supplementation can augment resistance training-mediated gains in skeletal muscle mass even in individuals habitually consuming 'adequate' (i.e., >0.8 g kg⁻¹ day⁻¹) protein. Additionally, overfeeding energy with moderate to high-protein intake (15-25 % protein or 1.8-3.0 g kg⁻¹ day⁻¹) is associated with lean, but not fat mass accretion, when compared to overfeeding energy with low protein intake (5 % protein or ~0.68 g kg⁻¹ day⁻¹). Amino acids represent primary nutrient regulators of skeletal muscle anabolism, capable of enhancing lean mass accretion with resistance exercise and attenuating the loss of lean mass during periods of energy deficit, although factors such as protein dose, protein source, and timing of intake are likely important in mediating these effects.

Computer simulation of phase separation under a double temperature quench.

PubMed

Podariu, Iulia; Chakrabarti, Amitabha

2007-04-21

The authors numerically study a two-step quench process in an asymmetric binary mixture. The mixture is first quenched to an unstable state in the two-phase region. After a large phase-separated structure is formed, the authors again quench the system deeper. The second quench induces the formation of small secondary droplets inside the large domains created by the first quench. The authors characterize this secondary droplet growth in terms of the temperature of the first quench as well as the depth of the second one.

Comparison of rankings for lean meat based on results from a CT scanner and a video image analysis system.

PubMed

Jay, N P; van de Ven, R J; Hopkins, D L

2014-10-01

Coopworth cross lambs born over three years were examined in this study. Differences between two machines; a computer tomography (CT) scanner and a VIAScan® system for the estimation of carcase lean weight in lamb carcases was examined. The CT scanner provided a significantly higher estimate of carcase lean. The rank correlation (0.84) between the CT scanner and the VIAScan® system for the prediction of carcase lean was significant, but there was a different ranking for carcase lean depending on which machine was used. This has important ramifications for the use of VIAScan® data in the New Zealand Sheep Improvement Ltd genetic programme. Copyright © 2014 Elsevier Ltd. All rights reserved.

Disturbing Practices: Training Workers to Be Lean

ERIC Educational Resources Information Center

Yasukawa, Keiko; Brown, Tony; Black, Stephen

2014-01-01

Purpose: The purpose of this paper is to explore the possibilities for expansive learning during organisational change. It considers the introduction of "lean production" as a disturbance to the existing work practices. Design/methodology/approach: The paper considers two case studies of "lean production" training with…

Lean and the Learning Organization in Higher Education

ERIC Educational Resources Information Center

Francis, David E.

2014-01-01

Canadian post-secondary institutions are seeking enhanced efficiencies due to ongoing funding shortfalls and expanding teaching, research, and service mandates. These institutions have considered or enacted Lean methodology based on results reported by public service and healthcare organizations worldwide. Lean requires a high level of…

A prescription for Lean healthcare.

PubMed

Wood, David

2014-01-01

The adoption of Lean in the healthcare industry has been an important advancement, and not just for healthcare management. Evidence suggests that Lean can improve labour and capital efficiencies, reduce the throughput time for patients and enhance the quality of care. However, the adoption of Lean has generated large variations in results and even wider-ranging suggestions on how to implement Lean in a healthcare setting. In this article, the author examines three very similar hospitals that implemented Lean in the emergency department during the same time. Through an examination of longitudinal data and a collection of unstructured interviews, the author found that implementation does make a substantial difference to long-term results. Although the presence of strong and persistent leadership can have favourable results on performance in the short term, these performance improvements are not sustainable. To have a long-term impact, healthcare providers need to engage all of the stakeholders in the healthcare system and create a culture that is continuously focused on the improvement of the patient healthcare experience. Copyright © 2014 Longwoods Publishing.

Lean management-the journey from toyota to healthcare.

PubMed

Teich, Sorin T; Faddoul, Fady F

2013-04-01

The evolution of production systems is tightly linked to the story of Toyota Motor Company (TMC) that has its roots around 1918. The term "lean" was coined in 1990 following the exploration of the Toyota model that led to the "transference" thesis sustaining the concept that manufacturing problems and technologies are universal problems faced by management and that these concepts can be emulated in non-Japanese enterprises. Lean is a multi-faceted concept and requires organizations to exert effort along several dimensions simultaneously; some consider a successful implementation either achieving major strategic components of lean, implementing practices to support operational aspects, or providing evidence that the improvements are sustainable in the long term. The article explores challenges and opportunities faced by organizations that intend incorporating lean management principles and presents the specific context of the healthcare industry. Finally, the concepts of "essential few" and customer value are illustrated through a simple example of process change following lean principles, which was implemented in a dental school in the United States.

Investigating emergency room service quality using lean manufacturing.

PubMed

Abdelhadi, Abdelhakim

2015-01-01

The purpose of this paper is to investigate a lean manufacturing metric called Takt time as a benchmark evaluation measure to evaluate a public hospital's service quality. Lean manufacturing is an established managerial philosophy with a proven track record in industry. A lean metric called Takt time is applied as a measure to compare the relative efficiency between two emergency departments (EDs) belonging to the same public hospital. Outcomes guide managers to improve patient services and increase hospital performances. The patient treatment lead time within the hospital's two EDs (one department serves male and the other female patients) are the study's focus. A lean metric called Takt time is used to find the service's relative efficiency. Findings show that the lean manufacturing metric called Takt time can be used as an effective way to measure service efficiency by analyzing relative efficiency and identifies bottlenecks in different departments providing the same services. The paper presents a new procedure to compare relative efficiency between two EDs. It can be applied to any healthcare facility.

Lean Mass Loss Is Associated with Low Protein Intake during Dietary-Induced Weight Loss in Postmenopausal Women

PubMed Central

BOPP, MELANIE J.; HOUSTON, DENISE K.; LENCHIK, LEON; EASTER, LINDA; KRITCHEVSKY, STEPHEN B.; NICKLAS, BARBARA J.

2013-01-01

The health and quality-of-life implications of overweight and obesity span all ages in the United States. We investigated the association between dietary protein intake and loss of lean mass during weight loss in postmenopausal women through a retrospective analysis of a 20-week randomized, controlled diet and exercise intervention in women aged 50 to 70 years. Weight loss was achieved by differing levels of caloric restriction and exercise. The diet-only group reduced caloric intake by 2,800 kcal/week, and the exercise groups reduced caloric intake by 2,400 kcal/week and expended ~400 kcal/week through aerobic exercise. Total and appendicular lean mass was measured using dual energy x-ray absorptiometry. Linear regression analysis was used to examine the association between changes in lean mass and appendicular lean mass and dietary protein intake. Average weight loss was 10.8±4.0 kg, with an average of 32% of total weight lost as lean mass. Protein intake averaged 0.62 g/kg body weight/day (range=0.47 to 0.8 g/kg body weight/day). Participants who consumed higher amounts of dietary protein lost less lean mass and appendicular lean mass r(=0.3, P=0.01 and r=0.41, P<0.001, respectively). These associations remained significant after adjusting for intervention group and body size. Therefore, inadequate protein intake during caloric restriction may be associated with adverse body-composition changes in postmenopausal women. PMID:18589032

An economic analysis of a system wide Lean approach: cost estimations for the implementation of Lean in the Saskatchewan healthcare system for 2012-2014.

PubMed

Sari, Nazmi; Rotter, Thomas; Goodridge, Donna; Harrison, Liz; Kinsman, Leigh

2017-08-03

The costs of investing in health care reform initiatives to improve quality and safety have been underreported and are often underestimated. This paper reports direct and indirect cost estimates for the initial phase of the province-wide implementation of Lean activities in Saskatchewan, Canada. In order to obtain detailed information about each type of Lean event, as well as the total number of corresponding Lean events, we used the Provincial Kaizen Promotion Office (PKPO) Kaizen database. While the indirect cost of Lean implementation has been estimated using the corresponding wage rate for the event participants, the direct cost has been estimated using the fees paid to the consultant and other relevant expenses. The total cost for implementation of Lean over two years (2012-2014), including consultants and new hires, ranged from $44 million CAD to $49.6 million CAD, depending upon the assumptions used. Consultant costs accounted for close to 50% of the total. The estimated cost of Lean events alone ranged from $16 million CAD to $19.5 million CAD, with Rapid Process Improvement Workshops requiring the highest input of resources. Recognizing the substantial financial and human investments required to undertake reforms designed to improve quality and contain cost, policy makers must carefully consider whether and how these efforts result in the desired transformations. Evaluation of the outcomes of these investments must be part of the accountability framework, even prior to implementation.

Has Lean improved organizational decision making?

PubMed

Simons, Pascale; Benders, Jos; Bergs, Jochen; Marneffe, Wim; Vandijck, Dominique

2016-06-13

Purpose - Sustainable improvement is likely to be hampered by ambiguous objectives and uncertain cause-effect relations in care processes (the organization's decision-making context). Lean management can improve implementation results because it decreases ambiguity and uncertainties. But does it succeed? Many quality improvement (QI) initiatives are appropriate improvement strategies in organizational contexts characterized by low ambiguity and uncertainty. However, most care settings do not fit this context. The purpose of this paper is to investigate whether a Lean-inspired change program changed the organization's decision-making context, making it more amenable for QI initiatives. Design/methodology/approach - In 2014, 12 professionals from a Dutch radiotherapy institute were interviewed regarding their perceptions of a Lean program in their organization and the perceived ambiguous objectives and uncertain cause-effect relations in their clinical processes. A survey (25 questions), addressing the same concepts, was conducted among the interviewees in 2011 and 2014. The structured interviews were analyzed using a deductive approach. Quantitative data were analyzed using appropriate statistics. Findings - Interviewees experienced improved shared visions and the number of uncertain cause-effect relations decreased. Overall, more positive (99) than negative Lean effects (18) were expressed. The surveys revealed enhanced process predictability and standardization, and improved shared visions. Practical implications - Lean implementation has shown to lead to greater transparency and increased shared visions. Originality/value - Lean management decreased ambiguous objectives and reduced uncertainties in clinical process cause-effect relations. Therefore, decision making benefitted from Lean increasing QI's sustainability.

Blunted suppression of acyl-ghrelin in response to fructose ingestion in obese adolescents: the role of insulin resistance.

PubMed

Van Name, Michelle; Giannini, Cosimo; Santoro, Nicola; Jastreboff, Ania M; Kubat, Jessica; Li, Fangyong; Kursawe, Romy; Savoye, Mary; Duran, Elvira; Dziura, James; Sinha, Rajita; Sherwin, Robert S; Cline, Gary; Caprio, Sonia

2015-03-01

Fructose consumption has risen alongside obesity and diabetes. Gut hormones involved in hunger and satiety (ghrelin and PYY) may respond differently to fructose compared with glucose ingestion. This study evaluated the effects of glucose and fructose ingestion on ghrelin and PYY in lean and obese adolescents with differing insulin sensitivity. Adolescents were divided into lean (n = 14), obese insulin sensitive (n = 12) (OIS), and obese insulin resistant (n = 15) (OIR). In a double-blind, cross-over design, subjects drank 75 g of glucose or fructose in random order, serum was obtained every 10 minutes for 60 minutes. Baseline acyl-ghrelin was highest in lean and lowest in OIR (P = 0.02). After glucose ingestion, acyl-ghrelin decreased similarly in lean and OIS but was lower in OIR (vs. lean, P = 0.03). Suppression differences were more pronounced after fructose (lean vs. OIS, P = 0.008, lean vs. OIR, P < 0.001). OIS became significantly hungrier after fructose (P = 0.015). PYY was not significantly different at baseline, varied minimally after glucose, and rose after fructose. Compared with lean, OIS adolescents have impaired acyl-ghrelin responses to fructose but not glucose, whereas OIR adolescents have blunted responses to both. Diminished suppression of acyl-ghrelin in childhood obesity, particularly if accompanied by insulin resistance, may promote hunger and overeating. © 2015 The Obesity Society.

Body composition and bone mineral density of national football league players.

PubMed

Dengel, Donald R; Bosch, Tyler A; Burruss, T Pepper; Fielding, Kurt A; Engel, Bryan E; Weir, Nate L; Weston, Todd D

2014-01-01

The purpose of the present study was to examine the body composition of National Football League (NFL) players before the start of the regular season. Four hundred eleven NFL players were measured for height, weight and lean, fat, and bone mass using dual-energy x-ray absorptiometry (DXA). Subjects were categorized by their offensive or defensive position for comparison. On average, positions that mirror each other (i.e., offensive lineman [OL] vs. defensive lineman [DL]) have very similar body composition. Although OL had more fat mass than DL, they were similar in total and upper and lower lean mass. Linebackers (LB) and running backs (RB) were similar for all measures of fat and lean mass. Tight ends were unique in that they were similar to RB and LB on measures of fat mass; however, they had greater lean mass than both RB and LB and upper-body lean mass that was similar to OL. Quarterbacks and punters/kickers were similar in fat and lean masses. All positions had normal levels of bone mineral density. The DXA allowed us to measure differences in lean mass between arms and legs for symmetry assessments. Although most individuals had similar totals of lean mass in each leg and or arms, there were outliers who may be at risk for injury. The data presented demonstrate not only differences in total body composition, but also show regional body composition differences that may provide positional templates.

Adipocyte resistin mRNA levels are down-regulated by laparoscopic ovarian electrocautery in both obese and lean women with polycystic ovary syndrome.

PubMed

Seow, Kok-Min; Juan, Chi-Chang; Ho, Low-Tone; Hsu, Yung-Pei; Lin, Yu-Hung; Huang, Lee-Wen; Hwang, Jiann-Loung

2007-04-01

The aim of this study was to investigate serum and adipocyte mRNA expression of resistin in lean and obese women with polycystic ovary syndrome (PCOS) before and 3 months after laparoscopic ovarian electrocauterization (LOE). Adipose tissue obtained from 12 women with PCOS (six obese and six lean, body mass index > 27 kg m(-1) as threshold point) before and after LOE was analysed. Gene expression of resistin was measured by semi-quantitative RT-PCR. Ten lean, age-matched healthy women served as controls. Both lean and obese women with PCOS had significantly higher fasting and 2 h insulin and homeostasis model insulin resistance index (HOMA(IR)) values and lower fasting glucose-to-insulin ratios (G(0)/I(0)) than did the controls. The serum levels of glucose and insulin and HOMA(IR) were significantly decreased, and the G(0)/I(0) ratio was significantly increased 3 months after LOE. No difference was found in serum resistin levels between controls and either obese or lean women with PCOS before LOE, nor between PCOS patients before and after LOE. However, resistin mRNA expression levels in both lean and obese women with PCOS before LOE were significantly higher than that in controls and were decreased significantly after LOE back to control levels. Local resistin activity may be actively involved in the pathogenesis of PCOS. LOE reduces insulin resistance and down-regulates resistin mRNA expression in lean and obese women with PCOS.

40 CFR 81.335 - North Dakota.

Code of Federal Regulations, 2010 CFR

2010-07-01

... McKenzie County McLean County Mercer County Morton County Mountrail County Nelson County Oliver County... County McIntosh County McKenzie County McLean County Mercer County Morton County Mountrail County Nelson... County McLean County Mercer County Morton County Mountrail County Nelson County Oliver County Pembina...

Galaxy Zoo: the interplay of quenching mechanisms in the group environment★

NASA Astrophysics Data System (ADS)

Smethurst, R. J.; Lintott, C. J.; Bamford, S. P.; Hart, R. E.; Kruk, S. J.; Masters, K. L.; Nichol, R. C.; Simmons, B. D.

2017-08-01

Does the environment of a galaxy directly influence the quenching history of a galaxy? Here, we investigate the detailed morphological structures and star formation histories of a sample of SDSS group galaxies with both classifications from Galaxy Zoo 2 and near ultra-violet (NUV) detections in GALEX. We use the optical and NUV colours to infer the quenching time and rate describing a simple exponentially declining star formation history for each galaxy, along with a control sample of field galaxies. We find that the time since quenching and the rate of quenching do not correlate with the relative velocity of a satellite but are correlated with the group potential. This quenching occurs within an average quenching time-scale of ˜ 2.5 Gyr from star forming to complete quiescence, during an average infall time (from ˜10R200 to 0.01R200) of ˜ 2.6 Gyr. Our results suggest that the environment does play a direct role in galaxy quenching through quenching mechanisms that are correlated with the group potential, such as harassment, interactions or starvation. Environmental quenching mechanisms that are correlated with satellite velocity, such as ram-pressure stripping, are not the main cause of quenching in the group environment. We find that no single mechanism dominates over another, except in the most extreme environments or masses. Instead, an interplay of mergers, mass and morphological quenching and environment-driven quenching mechanisms dependent on the group potential drive galaxy evolution in groups.

Study of deformation behavior, structure and mechanical properties of the AlSiMnFe alloy during ECAP-PBP.

PubMed

Naizabekov, A B; Andreyachshenko, V A; Kocich, Radim

2013-01-01

The presented article deals with the effects of equal channel angular pressing (ECAP) with a newly adjusted die geometry on the microstructure and mechanical properties of the Al-Si-Mn-Fe alloy. This alloy was subjected to two modes of heat treatment followed by the ECAP process, which led to partial back pressure (ECAP-PBP). Ultra-fine grained (UFG) structure formed through ECAP-PBP process has been studied by methods of optical as well as electron microscopy. The obtained results indicate that quenched alloys, in comparison to slowly cooled alloys, do not contain large brittle particles which subsequently initiate a premature creation of cracks. It was shown that the mechanical properties of these alloys after such processing depend first and foremost on the selected type of heat treatment and on the number of performed passes. The maximum of ultimate tensile strength (417 MPa) was obtained for quenched alloy after 3 passes. On the other hand, maximum ductility was found in slowly cooled alloy after second pass. Further passes reduced strength due to the brittle behavior of excluded particles. One of the partial findings is that there is only a small dependency of the resulting size of grains on previously applied thermal processing. The minimum grain sizes were obtained after 3 passages, where their size ranged between 0.4 and 0.8 μm. The application of quick cooling after heat processing due to the occurrence of finer precipitates in the matrix seems to produce better results. Copyright © 2012 Elsevier Ltd. All rights reserved.

Determination of Aflatoxin M1 and Chloramphenicol in Milk Based on Background Fluorescence Quenching Immunochromatographic Assay.

PubMed

Wu, Xiaoxia; Tian, Xiaofeng; Xu, Lihua; Li, Jiutong; Li, Xinxia; Wang, Yuwen

2017-01-01

Harsh demanding has been exposed on the concentration of aflatoxin M1 (AFM1) and chloramphenicol (CAP) in milk. In this study, we developed a new method based on background fluorescence quenching immunochromatographic assay (bFQICA) to detect AFM1 and CAP in milk. The detection limit for AFM1 was 0.0009 ng/mL, while that for the CAP was 0.0008 ng/mL. The assay variability was determined with 3 AFM1 standards (i.e., 0.25 ng/mL, 0.5 ng/mL, and 1.0 ng/mL), and the actual detection value was 0.2497, 0.5329, and 1.0941, respectively. For the assay variability of 3 CAP standards (i.e., 0.10 ng/mL, 0.30 ng/mL, and 0.50 ng/mL), the actual detection value was 0.0996, 0.3096, and 0.4905, respectively. The recovery rate of AFM1 was 99.7%-101.7%, while that for CAP was 95.3%-97.6%. For the test stability, AFM1 and CAP showed satisfactory test stability even at month 5. Compared with the sensitivity of liquid chromatography-mass spectrometry (LC-MS) method, no statistical difference was noticed in results of the bFQICA. Our method is convenient for the detection of AFM1 and CAP in milk with a test duration of about 8 minutes. Additionally, an internal WiFi facility is provided in the system allowing for quick connection and storage in the intelligent cell phone.

Learning Lean: A Survey of Industry Lean Needs

ERIC Educational Resources Information Center

Fliedner, Gene; Mathieson, Kieran

2009-01-01

The authors examined business practitioners' preferences for higher education curricula design in general and for what graduates should know about Lean, or waste-reduction efforts. The authors conducted a Web-based survey and found that practitioners are not as concerned about graduates' possessing specific technical skills as they are about them…

Characterization of complexities in combustion instability in a lean premixed gas-turbine model combustor.

PubMed

Gotoda, Hiroshi; Amano, Masahito; Miyano, Takaya; Ikawa, Takuya; Maki, Koshiro; Tachibana, Shigeru

2012-12-01

We characterize complexities in combustion instability in a lean premixed gas-turbine model combustor by nonlinear time series analysis to evaluate permutation entropy, fractal dimensions, and short-term predictability. The dynamic behavior in combustion instability near lean blowout exhibits a self-affine structure and is ascribed to fractional Brownian motion. It undergoes chaos by the onset of combustion oscillations with slow amplitude modulation. Our results indicate that nonlinear time series analysis is capable of characterizing complexities in combustion instability close to lean blowout.

The Statistical point of view of Quality: the Lean Six Sigma methodology

PubMed Central

Viti, Andrea; Terzi, Alberto

2015-01-01

Six Sigma and Lean are two quality improvement methodologies. The Lean Six Sigma methodology is applicable to repetitive procedures. Therefore, the use of this methodology in the health-care arena has focused mainly on areas of business operations, throughput, and case management and has focused on efficiency outcomes. After the revision of methodology, the paper presents a brief clinical example of the use of Lean Six Sigma as a quality improvement method in the reduction of the complications during and after lobectomies. Using Lean Six Sigma methodology, the multidisciplinary teams could identify multiple modifiable points across the surgical process. These process improvements could be applied to different surgical specialties and could result in a measurement, from statistical point of view, of the surgical quality. PMID:25973253

The Statistical point of view of Quality: the Lean Six Sigma methodology.

PubMed

Bertolaccini, Luca; Viti, Andrea; Terzi, Alberto

2015-04-01

Six Sigma and Lean are two quality improvement methodologies. The Lean Six Sigma methodology is applicable to repetitive procedures. Therefore, the use of this methodology in the health-care arena has focused mainly on areas of business operations, throughput, and case management and has focused on efficiency outcomes. After the revision of methodology, the paper presents a brief clinical example of the use of Lean Six Sigma as a quality improvement method in the reduction of the complications during and after lobectomies. Using Lean Six Sigma methodology, the multidisciplinary teams could identify multiple modifiable points across the surgical process. These process improvements could be applied to different surgical specialties and could result in a measurement, from statistical point of view, of the surgical quality.

Comparative study: TQ and Lean Production ownership models in health services

PubMed Central

Eiro, Natalia Yuri; Torres-Junior, Alvair Silveira

2015-01-01

Objective: compare the application of Total Quality (TQ) models used in processes of a health service, cases of lean healthcare and literature from another institution that has also applied this model. Method: this is a qualitative research that was conducted through a descriptive case study. Results: through critical analysis of the institutions studied it was possible to make a comparison between the traditional quality approach checked in one case and the theoretical and practice lean production approach used in another case and the specifications are described below. Conclusion: the research identified that the lean model was better suited for people that work systemically and generate the flow. It also pointed towards some potential challenges in the introduction and implementation of lean methods in health. PMID:26487134

Lean healthcare from a change management perspective.

PubMed

van Rossum, Lisa; Aij, Kjeld Harald; Simons, Frederique Elisabeth; van der Eng, Niels; Ten Have, Wouter Dirk

2016-05-16

Purpose - Lean healthcare is used in a growing number of hospitals to increase efficiency and quality of care. However, healthcare organizations encounter problems with the implementation of change initiatives due to an implementation gap: the gap between strategy and execution. From a change management perspective, the purpose of this paper is to increase scientific knowledge regarding factors that diminish the implementation gap and make the transition from the "toolbox lean" toward an actual transformation to lean healthcare. Design/methodology/approach - A cross-sectional study was executed in an operating theatre of a Dutch University Medical Centre. Transformational leadership was expected to ensure the required top-down commitment, whereas team leadership creates the required active, bottom-up behavior of employees. Furthermore, professional and functional silos and a hierarchical structure were expected to impede the workforce flexibility in adapting organizational elements and optimize the entire process flow. Findings - The correlation and regression analyses showed positive relations between the transformational leadership and team leadership styles and lean healthcare implementation. The results also indicated a strong relation between workforce flexibility and the implementation of lean healthcare. Originality/value - With the use of a recently developed change management model, the Change Competence Model, the authors suggest leadership and workforce flexibility to be part of an organization's change capacity as crucial success factor for a sustainable transformation to lean healthcare.

The relationship between IL-18 and atherosclerotic cardiovascular risk in Egyptian lean women with polycystic ovary syndrome.

PubMed

Dawood, Alaaeldin; Alkafrawy, Nabil; Saleh, Said; Noreldin, Rasha; Zewain, Shimaa

2018-04-01

Polycystic ovarian syndrome (PCOS) is the most common endocrine disorder among women of reproductive age. The evidence in support of low-grade inflammation in PCOS as an etiology is emerging. Inflammation is likely to be associated with other prominent aspects of PCOS including insulin resistance (IR) and cardiovascular disease (CVD) risk. Interleukin-18 (IL-18) is considered as a strong marker of inflammation. Evaluation of the relation between serum IL-18 and atherosclerotic CVD (ASCVD) risk in Egyptian lean females with PCO. This study included control group of healthy lean normally menstruating females, lean PCOS group (BMI < 25 kg/m 2 ), and obese PCOS group (BMI > 25 kg/m 2 ) presented with infertility and diagnosed according to Rotterdam criteria. Measurements of serum lipid profile, IR, and IL-18 were done. Lipid accumulation product (LAP), IR and ASCVD risk were significantly higher in PCOS patients (lean and obese) compared to controls and in obese compared to lean. Serum IL-18 was significantly higher in the PCOV groups compared to the controls and correlated directly with LAP, IR and ASCVD risk. IL-18 is elevated in PCOS patients even in lean ones and is correlated with IR and ASCVD risk.

The impact of Lean bundles on hospital performance: does size matter?

PubMed

Al-Hyari, Khalil; Abu Hammour, Sewar; Abu Zaid, Mohammad Khair Saleem; Haffar, Mohamed

2016-10-10

Purpose The purpose of this paper is to study the effect of the implementation of Lean bundles on hospital performance in private hospitals in Jordan and evaluate how much the size of organization can affect the relationship between Lean bundles implementation and hospital performance. Design/methodology/approach The research is considered as quantitative method (descriptive and hypothesis testing). Three statistical techniques were adopted to analyse the data. Structural equation modeling techniques and multi-group analysis were used to examine the research's hypothesis, and to perform the required statistical analysis of the data from the survey. Reliability analysis and confirmatory factor analysis were used to test the construct validity, reliability and measurement loadings that were performed. Findings Lean bundles have been identified as an effective approach that can dramatically improve the organizational performance of private hospitals in Jordan. Main Lean bundles - just in time, human resource management, and total quality management are applicable to large, small and medium hospitals without significant differences in advantages that depend on size. Originality/value According to the researchers' best knowledge, this is the first research that studies the impact of Lean bundles implementation in healthcare sector in Jordan. This research also makes a significant contribution for decision makers in healthcare to increase their awareness of Lean bundles.

Early deprivation increases high-leaning behavior, a novel anxiety-like behavior, in the open field test in rats.

PubMed

Kuniishi, Hiroshi; Ichisaka, Satoshi; Yamamoto, Miki; Ikubo, Natsuko; Matsuda, Sae; Futora, Eri; Harada, Riho; Ishihara, Kohei; Hata, Yoshio

2017-10-01

The open field test is one of the most popular ethological tests to assess anxiety-like behavior in rodents. In the present study, we examined the effect of early deprivation (ED), a model of early life stress, on anxiety-like behavior in rats. In ED animals, we failed to find significant changes in the time spent in the center or thigmotaxis area of the open field, the common indexes of anxiety-like behavior. However, we found a significant increase in high-leaning behavior in which animals lean against the wall standing on their hindlimbs while touching the wall with their forepaws at a high position. The high-leaning behavior was decreased by treatment with an anxiolytic, diazepam, and it was increased under intense illumination as observed in the center activity. In addition, we compared the high-leaning behavior and center activity under various illumination intensities and found that the high-leaning behavior is more sensitive to illumination intensity than the center activity in the particular illumination range. These results suggest that the high-leaning behavior is a novel anxiety-like behavior in the open field test that can complement the center activity to assess the anxiety state of rats. Copyright © 2017 Elsevier Ireland Ltd and Japan Neuroscience Society. All rights reserved.

True retention of nutrients on cooking of Australian retail lamb cuts of differing carcass classification characteristics.

PubMed

Kosulwat, Somkiat; Greenfield, Heather; Buckle, Kenneth A

2003-12-01

The true retention of nutrients (proximate principles and cholesterol) on cooking of three retail cuts from lambs classified by weight, sex and fatness score was investigated. Fat retentions of the total cut and of the lean portion of lamb legs and mid-loin chops were not affected by carcass fatness, weight and sex or their interactions, however, the fat retention of the total cut and of the lean portion of forequarter chops was affected by fat score, with forequarter chops from fat score 1 retaining more fat than did chops of carcasses of higher fat score. Overall, fat was lost by all cuts (total cut) on cooking, with only 70-80% of fat being retained, but fat content of lean only increased on cooking (retention >100%), indicating the passage of fat into the lean portion from the external fat cover during the cooking process. Carcass factors and their interactions had little or no effect on the protein, water and ash retentions of the total cut or the lean portions of the three cuts. Cholesterol retention by the lean portion of three cooked lamb cuts was not affected by any carcass factors or their interactions. Cholesterol retentions were ∼99% for total cuts and tended to be ∼102% for the lean portions.

Distinct effects of calorie restriction on adipose tissue cytokine and angiogenesis profiles in obese and lean mice

PubMed Central

2012-01-01

Background Obesity associates with low-grade inflammation and adipose tissue remodeling. Using sensitive high-throughput protein arrays we here investigated adipose tissue cytokine and angiogenesis-related protein profiles from obese and lean mice, and in particular, the influence of calorie restriction (CR). Methods Tissue samples from visceral fat were harvested from obese mice fed with a high-fat diet (60% of energy), lean controls receiving low-fat control diet as well as from obese and lean mice kept under CR (energy intake 70% of ad libitum intake) for 50 days. Protein profiles were analyzed using mouse cytokine and angiogenesis protein array kits. Results In obese and lean mice, CR was associated with 11.3% and 15.6% reductions in body weight, as well as with 4.0% and 4.6% reductions in body fat percentage, respectively. Obesity induced adipose tissue cytokine expressions, the most highly upregulated cytokines being IL-1ra, IL-2, IL-16, MCP-1, MIG, RANTES, C5a, sICAM-1 and TIMP-1. CR increased sICAM-1 and TIMP-1 expression both in obese and lean mice. Overall, CR showed distinct effects on cytokine expressions; in obese mice CR largely decreased but in lean mice increased adipose tissue cytokine expressions. Obesity was also associated with increased expressions of angiogenesis-related proteins, in particular, angiogenin, endoglin, endostatin, endothelin-1, IGFBP-3, leptin, MMP-3, PAI-1, TIMP-4, CXCL16, platelet factor 4, DPPIV and coagulation factor III. CR increased endoglin, endostatin and platelet factor 4 expressions, and decreased IGFBP-3, NOV, MMP-9, CXCL16 and osteopontin expressions both in obese and lean mice. Interestingly, in obese mice, CR decreased leptin and TIMP-4 expressions, whereas in lean mice their expressions were increased. CR decreased MMP-3 and PAI-1 only in obese mice, whereas CR decreased FGF acidic, FGF basic and coagulation factor III, and increased angiogenin and DPPIV expression only in lean mice. Conclusions CR exerts distinct effects on adipocyte cytokine and angiogenesis profiles in obese and lean mice. Our study also underscores the importance of angiogenesis-related proteins and cytokines in adipose tissue remodeling and development of obesity. PMID:22748184

Genetic variation in efficiency to deposit fat and lean meat in Norwegian Landrace and Duroc pigs.

PubMed

Martinsen, K H; Ødegård, J; Olsen, D; Meuwissen, T H E

2015-08-01

Feed costs amount to approximately 70% of the total costs in pork production, and feed efficiency is, therefore, an important trait for improving pork production efficiency. Production efficiency is generally improved by selection for high lean growth rate, reduced backfat, and low feed intake. These traits have given an effective slaughter pig but may cause problems in piglet production due to sows with limited body reserves. The aim of the present study was to develop a measure for feed efficiency that expressed the feed requirements per 1 kg deposited lean meat and fat, which is not improved by depositing less fat. Norwegian Landrace ( = 8,161) and Duroc ( = 7,202) boars from Topigs Norsvin's testing station were computed tomography scanned to determine their deposition of lean meat and fat. The trait was analyzed in a univariate animal model, where total feed intake in the test period was the dependent variable and fat and lean meat were included as random regression cofactors. These cofactors were measures for fat and lean meat efficiencies of individual boars. Estimation of fraction of total genetic variance due to lean meat or fat efficiency was calculated by the ratio between the genetic variance of the random regression cofactor and the total genetic variance in total feed intake during the test period. Genetic variance components suggested there was significant genetic variance among Norwegian Landrace and Duroc boars in efficiency for deposition of lean meat (0.23 ± 0.04 and 0.38 ± 0.06) and fat (0.26 ± 0.03 and 0.17 ± 0.03) during the test period. The fraction of the total genetic variance in feed intake explained by lean meat deposition was 12% for Norwegian Landrace and 15% for Duroc. Genetic fractions explained by fat deposition were 20% for Norwegian Landrace and 10% for Duroc. The results suggested a significant part of the total genetic variance in feed intake in the test period was explained by fat and lean meat efficiency. These new efficiency measures may give the breeders opportunities to select for animals with a genetic potential to deposit lean meat efficiently and at low feed costs in slaughter pigs rather than selecting for reduced the feed intake and backfat.

Galaxy Zoo: Major Galaxy Mergers Are Not a Significant Quenching Pathway

NASA Astrophysics Data System (ADS)

Weigel, Anna K.; Schawinski, Kevin; Caplar, Neven; Carpineti, Alfredo; Hart, Ross E.; Kaviraj, Sugata; Keel, William C.; Kruk, Sandor J.; Lintott, Chris J.; Nichol, Robert C.; Simmons, Brooke D.; Smethurst, Rebecca J.

2017-08-01

We use stellar mass functions to study the properties and the significance of quenching through major galaxy mergers. In addition to SDSS DR7 and Galaxy Zoo 1 data, we use samples of visually selected major galaxy mergers and post-merger galaxies. We determine the stellar mass functions of the stages that we would expect major-merger-quenched galaxies to pass through on their way from the blue cloud to the red sequence: (1) major merger, (2) post-merger, (3) blue early type, (4) green early type, and (5) red early type. Based on their similar mass function shapes, we conclude that major mergers are likely to form an evolutionary sequence from star formation to quiescence via quenching. Relative to all blue galaxies, the major-merger fraction increases as a function of stellar mass. Major-merger quenching is inconsistent with the mass and environment quenching model. At z˜ 0, major-merger-quenched galaxies are unlikely to constitute the majority of galaxies that transition through the green valley. Furthermore, between z˜ 0-0.5, major-merger-quenched galaxies account for 1%-5% of all quenched galaxies at a given stellar mass. Major galaxy mergers are therefore not a significant quenching pathway, neither at z˜ 0 nor within the last 5 Gyr. The majority of red galaxies must have been quenched through an alternative quenching mechanism that causes a slow blue to red evolution. .

40 CFR 63.7295 - What requirements must I meet for quenching?

Code of Federal Regulations, 2010 CFR

2010-07-01

... (CONTINUED) National Emission Standards for Hazardous Air Pollutants for Coke Ovens: Pushing, Quenching, and... each quench tower and backup quench station at a new or existing coke oven battery. (1) For the quenching of hot coke, you must meet the requirements in paragraph (a)(1)(i) or (ii) of this section. (i...

40 CFR 63.7295 - What requirements must I meet for quenching?

Code of Federal Regulations, 2011 CFR

2011-07-01

... (CONTINUED) National Emission Standards for Hazardous Air Pollutants for Coke Ovens: Pushing, Quenching, and... each quench tower and backup quench station at a new or existing coke oven battery. (1) For the quenching of hot coke, you must meet the requirements in paragraph (a)(1)(i) or (ii) of this section. (i...

40 CFR 63.7295 - What requirements must I meet for quenching?

Code of Federal Regulations, 2013 CFR

2013-07-01

... (CONTINUED) National Emission Standards for Hazardous Air Pollutants for Coke Ovens: Pushing, Quenching, and... each quench tower and backup quench station at a new or existing coke oven battery. (1) For the quenching of hot coke, you must meet the requirements in paragraph (a)(1)(i) or (ii) of this section. (i...

40 CFR 63.7295 - What requirements must I meet for quenching?

Code of Federal Regulations, 2014 CFR

2014-07-01

... (CONTINUED) National Emission Standards for Hazardous Air Pollutants for Coke Ovens: Pushing, Quenching, and... each quench tower and backup quench station at a new or existing coke oven battery. (1) For the quenching of hot coke, you must meet the requirements in paragraph (a)(1)(i) or (ii) of this section. (i...

40 CFR 63.7295 - What requirements must I meet for quenching?

Code of Federal Regulations, 2012 CFR

2012-07-01

... (CONTINUED) National Emission Standards for Hazardous Air Pollutants for Coke Ovens: Pushing, Quenching, and... each quench tower and backup quench station at a new or existing coke oven battery. (1) For the quenching of hot coke, you must meet the requirements in paragraph (a)(1)(i) or (ii) of this section. (i...

Computational quench model applicable to the SMES/CICC

NASA Astrophysics Data System (ADS)

Luongo, Cesar A.; Chang, Chih-Lien; Partain, Kenneth D.

1994-07-01

A computational quench model accounting for the hydraulic peculiarities of the 200 kA SMES cable-in-conduit conductor has been developed. The model is presented and used to simulate the quench on the SMES-ETM. Conclusions are drawn concerning quench detection and protection. A plan for quench model validation is presented.

Characterization of plasma current quench during disruptions at HL-2A

NASA Astrophysics Data System (ADS)

Zhu, Jinxia; Zhang, Yipo; Dong, Yunbo; HL-2A Team

2017-05-01

The most essential assumptions of physics for the evaluation of electromagnetic forces on the plasma-facing components due to a disruption-induced eddy current are characteristics of plasma current quenches including the current quench rate or its waveforms. The characteristics of plasma current quenches at HL-2A have been analyzed during spontaneous disruptions. Both linear decay and exponential decay are found in the disruptions with the fastest current quenches. However, there are two stages of current quench in the slow current quench case. The first stage with an exponential decay and the second stage followed by a rapid linear decay. The faster current quench rate corresponds to the faster movement of plasma displacement. The parameter regimes on the current quench time and the current quench rates have been obtained from disruption statistics at HL-2A. There exists no remarkable difference for distributions obtained between the limiter and the divertor configuration. This data from HL-2A provides basic data of the derivation of design criteria for a large-sized machine during the current decay phase of the disruptions.

Novel water-air circulation quenching process for AISI 4140 steel

NASA Astrophysics Data System (ADS)

Zheng, Liyun; Zheng, Dawei; Zhao, Lixin; Wang, Lihui; Zhang, Kai

2013-11-01

AISI 4140 steel is usually used after quenching and tempering. During the heat treatment process in industry production, there are some problems, such as quenching cracks, related to water-cooling and low hardness due to oil quenching. A water-air circulation quenching process can solve the problems of quenching cracks with water and the high cost quenching with oil, which is flammable, unsafe and not enough to obtain the required hardness. The control of the water-cooling and air-cooling time is a key factor in the process. This paper focuses on the quenching temperature, water-air cycle time and cycle index to prevent cracking for AISI 4140 steel. The optimum heat treatment parameters to achieve a good match of the strength and toughness of AISI 4140 steel were obtained by repeated adjustment of the water-air circulation quenching process parameters. The tensile strength, Charpy impact energy at -10 °C and hardness of the heat treated AISI 4140 steel after quenching and tempering were approximately 1098 MPa, 67.5 J and 316 HB, respectively.

Improvement of laboratory turnaround time using lean methodology.

PubMed

Gupta, Shradha; Kapil, Sahil; Sharma, Monica

2018-05-14

Purpose The purpose of this paper is to discuss the implementation of lean methodology to reduce the turnaround time (TAT) of a clinical laboratory in a super speciality hospital. Delays in report delivery lead to delayed diagnosis increased waiting time and decreased customer satisfaction. The reduction in TAT will lead to increased patient satisfaction, quality of care, employee satisfaction and ultimately the hospital's revenue. Design/methodology/approach The generic causes resulting in increasing TAT of clinical laboratories were identified using lean tools and techniques such as value stream mapping (VSM), Gemba, Pareto Analysis and Root Cause Analysis. VSM was used as a tool to analyze the current state of the process and further VSM was used to design the future state with suggestions for process improvements. Findings This study identified 12 major non-value added factors for the hematology laboratory and 5 major non-value added factors for the biochemistry lab which were acting as bottlenecks resulting in limiting throughput. A four-month research study by the authors together with hospital quality department and laboratory staff members led to reduction of the average TAT from 180 to 95minutes in the hematology lab and from 268 to 208 minutes in the biochemistry lab. Practical implications Very few improvement initiatives in Indian healthcare are based on industrial engineering tools and techniques, which might be due to a lack of interaction between healthcare and engineering. The study provides a positive outcome in terms of improving the efficiency of services in hospitals and identifies a scope for lean in the Indian healthcare sector. Social implications Applying lean in the Indian healthcare sector gives its own potential solution to the problem caused, due to a wide gap between lean accessibility and lean implementation. Lean helped in changing the mindset of an organization toward providing the highest quality of services with faster delivery at an optimal cost. Originality/value This paper is an effort to reduce the gap between healthcare and industrial engineering and enhancing the use of lean practices in Indian healthcare. The study is motivated toward implementing lean methodology successfully in services.

Criteria pollutant and greenhouse gas emissions from CNG transit buses equipped with three-way catalysts compared to lean-burn engines and oxidation catalyst technologies.

PubMed

Yoon, Seungju; Collins, John; Thiruvengadam, Arvind; Gautam, Mridul; Herner, Jorn; Ayala, Alberto

2013-08-01

Engine and exhaust control technologies applied to compressed natural gas (CNG) transit buses have advanced from lean-burn, to lean-burn with oxidation catalyst (OxC), to stoichiometric combustion with three-way catalyst (TWC). With this technology advancement, regulated gaseous and particulate matter emissions have been significantly reduced. Two CNG transit buses equipped with stoichiometric combustion engines and TWCs were tested on a chassis dynamometer, and their emissions were measured. Emissions from the stoichiometric engines with TWCs were then compared to the emissions from lean-burn CNG transit buses tested in previous studies. Stoichiometric combustion with TWC was effective in reducing emissions of oxides of nitrogen (NO(x)), particulate matter (PM), and nonmethane hydrocarbon (NMHC) by 87% to 98% depending on pollutants and test cycles, compared to lean combustion. The high removal efficiencies exceeded the emission reduction required from the certification standards, especially for NO(x) and PM. While the certification standards require 95% and 90% reductions for NO(x) and PM, respectively, from the engine model years 1998-2003 to the engine model year 2007, the measured NO(x) and PM emissions show 96% and 95% reductions, respectively, from the lean-burn engines to the stoichiometric engines with TWC over the transient Urban Dynamometer Driving Schedule (UDDS) cycle. One drawback of stoichiometric combustion with TWC is that this technology produces higher carbon monoxide (CO) emissions than lean combustion. In regard to controlling CO emissions, lean combustion with OxC is more effective than stoichiometric combustion. Stoichiometric combustion with TWC produced higher greenhouse gas (GHG) emissions including carbon dioxide (CO2) and methane (CH4) than lean combustion during the UDDS cycle, but lower GHG emissions during the steady-state cruise cycle. Stoichiometric combustion with three-way catalyst is currently the best emission control technology available for compressed natural gas (CNG) transit buses to meet the stringent U.S. Environmental Protection Agency (EPA) 2010 heavy-duty engine NO(x) emissions standard. For existing lean-burn CNG transit buses in the fleet, oxidation catalyst would be the most effective retrofit technology for the control of NMHC and CO emissions.

Virtual modelling of components of a production system as the tool of lean engineering

NASA Astrophysics Data System (ADS)

Monica, Z.

2015-11-01

Between the most effective techniques of manufacturing management is considered the Lean Engineering. The term “lean engineering” was created by Japanese manufacturers. The high efficiency of this method resulted in a meaningful growth in concern in the philosophy of Lean among European companies, and consequently the use of its European markets. Lean philosophy is an approach to manufacturing to minimize the use of all resources, including time. These are resources that are used in the company for a variety of activities. This implies, first identify and then eliminate activities which does not generate added value in the field of design, manufacturing, supply chain management, and customer relations. The producers of these principles not only employ teams multi-professional employees at all levels of the organization, but also use a more automated machines to produce large quantities of products with a high degree of diversity. Lean Engineering is to use a number of principles and practical guidelines that allow you to reduce costs by eliminating absolute extravagance, and also simplification of all manufacturing processes and maintenance. Nowadays it could be applied the powerful engineering programs to realize the concept of Lean Engineering. They could be described using the term CAD/CAM/CAE. They consist of completely different packages for both the design of elements, as well process design. Their common feature is generally considered with their application area. They are used for computer programs assisting the design, development and manufacturing phases of a manufacturing process. The idea of the presented work is to use the Siemens NX software for aiding the process of Lean Engineering system creating. The investigated system is a robotized workcell. In the NX system are created the components of the designed workcell such as machine tools, as industrial robot, as conveyors and buffers. The system let to functionally link these components to simulate the work process and to introduce the rules of Lean Engineering. The purpose is also to determine the rules of Lean designing in such advanced design and simulation environments.

Comparison of muscle/lean mass measurement methods: correlation with functional and biochemical testing.

PubMed

Buehring, B; Siglinsky, E; Krueger, D; Evans, W; Hellerstein, M; Yamada, Y; Binkley, N

2018-03-01

DXA-measured lean mass is often used to assess muscle mass but has limitations. Thus, we compared DXA lean mass with two novel methods-bioelectric impedance spectroscopy and creatine (methyl-d3) dilution. The examined methodologies did not measure lean mass similarly and the correlation with muscle biomarkers/function varied. Muscle function tests predict adverse health outcomes better than lean mass measurement. This may reflect limitations of current mass measurement methods. Newer approaches, e.g., bioelectric impedance spectroscopy (BIS) and creatine (methyl-d3) dilution (D3-C), may more accurately assess muscle mass. We hypothesized that BIS and D3-C measured muscle mass would better correlate with function and bone/muscle biomarkers than DXA measured lean mass. Evaluations of muscle/lean mass, function, and serum biomarkers were obtained in older community-dwelling adults. Mass was assessed by DXA, BIS, and orally administered D3-C. Grip strength, timed up and go, and jump power were examined. Potential muscle/bone serum biomarkers were measured. Mass measurements were compared with functional and serum data using regression analyses; differences between techniques were determined by paired t tests. Mean (SD) age of the 112 (89F/23M) participants was 80.6 (6.0) years. The lean/muscle mass assessments were correlated (.57-.88) but differed (p < 0.0001) from one another with DXA total body less head being highest at 37.8 (7.3) kg, D3-C muscle mass at 21.1 (4.6) kg, and BIS total body intracellular water at 17.4 (3.5) kg. All mass assessment methods correlated with grip strength and jump power (R = 0.35-0.63, p < 0.0002), but not with gait speed or repeat chair rise. Lean mass measures were unrelated to the serum biomarkers measured. These three methodologies do not similarly measure muscle/lean mass and should not be viewed as being equivalent. Functional tests assessing maximal muscle strength/power (grip strength and jump power) correlated with all mass measures whereas gait speed was not. None of the selected serum measures correlated with mass. Efforts to optimize muscle mass assessment and identify their relationships with health outcomes are needed.

Differences in fairness and trust between lean and corpulent men.

PubMed

Kubera, B; Klement, J; Wagner, C; Rädel, C; Eggeling, J; Füllbrunn, S; Kaczmarek, M C; Levinsky, R; Peters, A

2016-11-01

Employment disparities are known to exist between lean and corpulent people, for example, corpulent people are less likely to be hired and get lower wages. The reasons for these disparities between weight groups are not completely understood. We hypothesize (i) that economic decision making differs between lean and corpulent subjects, (ii) that these differences are influenced by peoples' blood glucose concentrations and (iii) by the body weight of their opponents. A total of 20 lean and 20 corpulent men were examined, who performed a large set of economic games (ultimatum game, trust game and risk game) under euglycemic and hypoglycemic conditions induced by the glucose clamp technique. In the ultimatum game, lean men made less fair decisions and offered 16% less money than corpulent men during euglycemia (P=0.042). During hypoglycemia, study participants of both weight groups accepted smaller amounts of money than during euglycemia (P=0.031), indicating that a lack of energy makes subjects to behave more like a Homo Economicus. In the trust game, lean men allocated twice as much money to lean than to corpulent trustees during hypoglycemia (P<0.001). Risk-seeking behavior did not differ between lean and corpulent men. Our data show that economic decision making is affected by both, the body weight of the participants and the body weight of their opponents, and that blood glucose concentrations should be taken into consideration when analyzing economic decision making. When relating these results to the working environment, the weight bias in economic decision making may be also relevant for employment disparities.

Improvement of emergency department patient flow using lean thinking.

PubMed

Sánchez, Miquel; Suárez, Montse; Asenjo, María; Bragulat, Ernest

2018-05-01

To apply lean thinking in triage acuity level-3 patients in order to improve emergency department (ED) throughtput and waiting time. A prospective interventional study. An ED of a tertiary care hospital. Triage acuity level-3 patients. To apply lean techniques such as value stream mapping, workplace organization, reduction of wastes and standardization by the frontline staff. Two periods were compared: (i) pre-lean: April-September, 2015; and (ii) post-lean: April-September, 2016. Variables included: median process time (time from beginning of nurse preparation to the end of nurse finalization after doctor disposition) of both discharged and transferred to observation patients; median length of stay; median waiting time; left without being seen, 72-h revisit and mortality rates, and daily number of visits. There was no additional staff or bed after lean implementation. Despite an increment in the daily number of visits (+8.3%, P < 0.001), significant reductions in process time of discharged (182 vs 160 min, P < 0.001) and transferred to observation (186 vs 176 min, P < 0.001) patients, in length of stay (389 vs 329 min, P < 0.001), and in waiting time (71 vs 48 min, P < 0.001) were achieved after lean implementation. No significant differences were registered in left without being seen rate (5.23% vs 4.95%), 72-h revisit rate (3.41% vs 3.93%), and mortality rate (0.23% vs 0.15%). Lean thinking is a methodology that can improve triage acuity level-3 patient flow in the ED, resulting in better throughput along with reduced waiting time.

Agreement between bioelectrical impedance and dual energy X-ray absorptiometry in assessing fat, lean and bone mass changes in adults after a lifestyle intervention.

PubMed

Macfarlane, Duncan J; Chan, Natalie T-Y; Tse, Michael A; Joe, Glen M

2016-01-01

We aimed to assess the agreement of a commercially available bioelectrical impedance analysis (BIA) device in measuring changes in fat, lean and bone mass over a 10-week lifestyle intervention, with dual energy X-ray absorptiometry (DXA) as reference. A sample of 136 volunteers (18-66 years) underwent a physical activity intervention to enhance lean mass and reduce fat mass. BIA (Tanita BC545) and DXA (Hologic Explorer) measures of whole-body composition were taken at baseline and at the end of the intervention. After an average of 74 ± 18 days intervention, DXA showed significant changes in 2 of 3 outcome variables: reduced fat mass of 0.802 ± 1.092 kg (P < 0.001), increased lean mass of 0.477 ± 0.966 kg (P < 0.001); minor non-significant increase of 0.007 ± 0.041 kg of bone mass (P = 0.052). The respective changes in BIA measures were a significant reduction of 0.486 ± 1.539 kg fat (P < 0.001), but non-significant increases of 0.084 ± 1.201 kg lean mass (P = 0.425), and 0.014 ± 0.091 kg bone (P = 0.074). Significant, but moderately weak, correlations were seen in absolute mass changes between DXA and BIA: 0.511 (fat), 0.362 (lean) and 0.172 (bone). Compared to DXA, BIA demonstrated mediocre agreement to changes in fat mass, but poor agreement to lean mass changes. BIA significantly underestimated the magnitude of changes in fat and lean mass compared to DXA.

Biomechanical mechanism of lateral trunk lean gait for knee osteoarthritis patients.

PubMed

Tokuda, Kazuki; Anan, Masaya; Takahashi, Makoto; Sawada, Tomonori; Tanimoto, Kenji; Kito, Nobuhiro; Shinkoda, Koichi

2018-01-03

The biomechanical mechanism of lateral trunk lean gait employed to reduce external knee adduction moment (KAM) for knee osteoarthritis (OA) patients is not well known. This mechanism may relate to the center of mass (COM) motion. Moreover, lateral trunk lean gait may affect motor control of the COM displacement. Uncontrolled manifold (UCM) analysis is an evaluation index used to understand motor control and variability of the motor task. Here we aimed to clarify the biomechanical mechanism to reduce KAM during lateral trunk lean gait and how motor variability controls the COM displacement. Twenty knee OA patients walked under two conditions: normal and lateral trunk lean gait conditions. UCM analysis was performed with respect to the COM displacement in the frontal plane. We also determined how the variability is structured with regards to the COM displacement as a performance variable. The peak KAM under lateral trunk lean gait was lower than that under normal gait. The reduced peak KAM observed was accompanied by medially shifted knee joint center, shortened distance of the center of pressure to knee joint center, and shortened distance of the knee-ground reaction force lever arm during the stance phase. Knee OA patients with lateral trunk lean gait could maintain kinematic synergy by utilizing greater segmental configuration variance to the performance variable. However, the COM displacement variability of lateral trunk lean gait was larger than that of normal gait. Our findings may provide clinical insights to effectively evaluate and prescribe gait modification training for knee OA patients. Copyright © 2017 Elsevier Ltd. All rights reserved.

Heat production and body temperature during cooling and rewarming in overweight and lean men.

PubMed

Claessens-van Ooijen, Anne M J; Westerterp, Klaas R; Wouters, Loek; Schoffelen, Paul F M; van Steenhoven, Anton A; van Marken Lichtenbelt, Wouter D

2006-11-01

To compare overweight and lean subjects with respect to thermogenesis and physiological insulation in response to mild cold and rewarming. Ten overweight men (mean BMI, 29.2 +/- 2.8 kg/m(2)) and 10 lean men (mean BMI, 21.1 +/- 2.0 kg/m(2)) were exposed to cold air for 1 hour, followed by 1 hour of rewarming. Body composition was determined by hydrodensitometry and deuterium dilution. Heat production and body temperatures were measured continuously by indirect calorimetry and thermistors, respectively. Muscle activity was recorded using electromyography. In both groups, heat production increased significantly during cooling (lean, p = 0.004; overweight, p = 0.006). The increase was larger in the lean group compared with the overweight group (p = 0.04). During rewarming, heat production returned to baseline in the overweight group and stayed higher compared with baseline in the lean group (p = 0.003). The difference in heat production between rewarming and baseline was larger in the lean (p = 0.01) than in the overweight subjects. Weighted body temperature of both groups decreased during cold exposure (lean, p = 0.002; overweight, p < 0.001) and did not return to baseline during rewarming. Overweight subjects showed a blunted mild cold-induced thermogenesis. The insulative cold response was not different among the groups. The energy-efficient response of the overweight subjects can have consequences for energy balance in the long term. The results support the concept of a dynamic heat regulation model instead of temperature regulation around a fixed set point.

The mass dependence of satellite quenching in Milky Way-like haloes

NASA Astrophysics Data System (ADS)

Phillips, John I.; Wheeler, Coral; Cooper, Michael C.; Boylan-Kolchin, Michael; Bullock, James S.; Tollerud, Erik

2015-02-01

Using the Sloan Digital Sky Survey, we examine the quenching of satellite galaxies around isolated Milky Way-like hosts in the local Universe. We find that the efficiency of satellite quenching around isolated galaxies is low and roughly constant over two orders of magnitude in satellite stellar mass (M⋆ = 108.5-1010.5 M⊙), with only ˜20 per cent of systems quenched as a result of environmental processes. While largely independent of satellite stellar mass, satellite quenching does exhibit clear dependence on the properties of the host. We show that satellites of passive hosts are substantially more likely to be quenched than those of star-forming hosts, and we present evidence that more massive haloes quench their satellites more efficiently. These results extend trends seen previously in more massive host haloes and for higher satellite masses. Taken together, it appears that galaxies with stellar masses larger than about 108 M⊙ are uniformly resistant to environmental quenching, with the relative harshness of the host environment likely serving as the primary driver of satellite quenching. At lower stellar masses (<108 M⊙), however, observations of the Local Group suggest that the vast majority of satellite galaxies are quenched, potentially pointing towards a characteristic satellite mass scale below which quenching efficiency increases dramatically.

Secondary Heating Under Quenching Cooling of Aluminum Alloys

NASA Astrophysics Data System (ADS)

Tsukrov, S. L.; Ber, L. B.

2017-07-01

Variants of secondary heating of aluminum alloys are considered, i.e., under quenching of plates in a water tank or on a horizontal quenching unit with water jet cooling, under continuous quenching of strips, and under quenching of tubes in vertical furnaces. Recommendation are given for removal or substantial reduction of the intensity of secondary heating under industrial conditions.

Integration of Lean Method in English Language Teaching and Learning: A New Perspective

ERIC Educational Resources Information Center

Tilfarlioglu, Filiz Yalçin; Anwer, Jivan Kamal

2017-01-01

Lean is regarded as a systematic approach to maximizing value by minimizing waste, and by flowing the product or service at the pull of the customer demand. These key concepts of "value," "flow," and "pull," align with the ultimate lean goal: "perfection," or a continuous striving for improvement in the…

The Influence of Lean on K-12 District Management: A Case Study

ERIC Educational Resources Information Center

Brown, Beverly

2011-01-01

For decades, policymakers and educators have focused on public school equity and adequacy, while paying little attention to efficiency. This qualitative single case study was designed to capture explicit information about Lean management, operations, and culture in a K-12 Michigan school district engaged in Lean training and implementation for a…

A Review and Perspective on Lean in Higher Education

ERIC Educational Resources Information Center

Balzer, William K.; Francis, David E.; Krehbiel, Timothy C.; Shea, Nicholas

2016-01-01

Purpose: The purpose of this paper is to synthesize the accumulated body of research on Lean in higher education, draw conclusions to help guide successful Lean implementations and propose future research directions to establish a rich base of knowledge that informs both practice and research. Design/methodology/approach This literature review…

Lean Principles and Defense Information Technology Acquisition: An Investigation of the Determinants of Successful Application

ERIC Educational Resources Information Center

Haley, M.

2013-01-01

The purpose of this study was to investigate whether or not there have been successful applications of lean manufacturing principles in highly variable defense IT environments. Specifically, the study assessed if implementation of the lean philosophies by a defense organization yielded repeatable, predictable results in software release schedules…

Recommendations on Coaching Strategies for Implementing Lean (Defense Acquisition Review Journal, August-November 2004)

DTIC Science & Technology

2004-01-01

Their answers are published in his book titled Lean Machines: Learning From the Leaders of The Next Industrial Revolution (Hermes, 2002; McCormack, 2002a...A. McCormack (Ed.), Lean machines—Learning from the leaders of the next industrial revolution (pp. 145–150). Annandale, VA: Publishers & Producers

Effect of Air Swirler Configuration on Lean Direct Injector Flow Structure and Combustion Performance with a 7-Point Lean Direct Injector Array

NASA Technical Reports Server (NTRS)

Hicks, Yolanda R.; Tacina, Kathleen M.; Anderson, Robert C.

2017-01-01

This paper examines the fundamentals of fuel-air mixing in a lean direct injection concept. Results are presented to investigate the effects of air swirler angle, element spacing, and center element offset on recirculation zone formation, flame stability and gaseous emissions.

The productive operating theatre and lean thinking systems.

PubMed

Kasivisvanathan, R; Chekairi, A

2014-11-01

The concept of 'lean thinking' first originated in the manufacturing industry as a means of improving productivity whilst maintaining quality through eliminating wasteful processes. The purpose of this article is to demonstrate how the principles of 'lean thinking' are relevant to healthcare and the operating theatre, with reference to our own institutional experience.

A Simulation of Lean Manufacturing: The Lean Lemonade Tycoon 2

ERIC Educational Resources Information Center

Ncube, Lisa B.

2010-01-01

This article discusses the functions and effectiveness of games and simulations in the learning processes, in particular as an experiential learning methodology. The application of the game Lemonade Tycoon in the development of lean manufacturing concepts is described. This article addresses the use of the game to teach the principles of lean…

Interlacing Mission, Strategic Planning, and Vision to Lean: Powerful DNA for Change

ERIC Educational Resources Information Center

Arnold, Alison; Flumerfelt, Shannon

2012-01-01

The authors' purpose for this article is to describe a K-12 public school district's journey to internalize and actualize its mission, strategic planning and vision as one coherent engagement using Lean principles and tools. Lean jointly comprises an organizational philosophy and management toolkit prominent in private, government, and nonprofit…

Nutritional contribution of lean beef in diets of adults: National Health and Nutrition Examination Survey, 1999-2004

USDA-ARS?s Scientific Manuscript database

The learning outcome was to understand the important contribution of lean beef to total nutrient intake in diets of American adults and to determine dietary intake differences between lean beef consumers and non-consumers. The National Health and Nutritional Examination Survey, 1999-2004, 24-hour di...

Benchmarking performance measurement and lean manufacturing in the rough mill

Treesearch

Dan Cumbo; D. Earl Kline; Matthew S. Bumgardner

2006-01-01

Lean manufacturing represents a set of tools and a stepwise strategy for achieving smooth, predictable product flow, maximum product flexibility, and minimum system waste. While lean manufacturing principles have been successfully applied to some components of the secondary wood products value stream (e.g., moulding, turning, assembly, and finishing), the rough mill is...

Human Behavior Based Exploratory Model for Successful Implementation of Lean Enterprise in Industry

ERIC Educational Resources Information Center

Sawhney, Rupy; Chason, Stewart

2005-01-01

Currently available Lean tools such as Lean Assessments, Value Stream Mapping, and Process Flow Charting focus on system requirements and overlook human behavior. A need is felt for a tool that allows one to baseline personnel, determine personnel requirements and align system requirements with personnel requirements. Our exploratory model--The…

Sport type and interpersonal and intrapersonal predictors of body dissatisfaction in high school female sport participants.

PubMed

Karr, Trisha M; Davidson, Denise; Bryant, Fred B; Balague, Gloria; Bohnert, Amy M

2013-03-01

Through multiple group structural equation modeling analyses, path models were used to test the predictive effects of sport type and both interpersonal (i.e., mothers' body dissatisfaction, family dynamics) and intrapersonal factors (i.e., athletic self-efficacy, body mass index [BMI]) on high school female sport participants' (N=627) body dissatisfaction. Sport types were classified as esthetic/lean (i.e., gymnastics), non-esthetic/lean (i.e., cross-country), or non-esthetic/non-lean (i.e., softball). Most participants reported low body dissatisfaction, and body dissatisfaction did not differ across sport types. Nevertheless, mothers' body dissatisfaction was positively associated with daughters' body dissatisfaction for non-esthetic/lean and non-esthetic/non-lean sport participants, and high family cohesion was predictive of body dissatisfaction among non-esthetic/lean sport participants. Across sport types, higher BMI was associated with greater body dissatisfaction, whereas greater athletic self-efficacy was associated with lower body dissatisfaction. These findings highlight the complex relationship between interpersonal and intrapersonal factors and body dissatisfaction in adolescent female sport participants. Copyright © 2012. Published by Elsevier Ltd.

Low NOx heavy fuel combustor concept program, phase 1

NASA Technical Reports Server (NTRS)

Cutrone, M. B.

1981-01-01

Combustion tests were completed with seven concepts, including three rich/lean concepts, three lean/lean concepts, and one catalytic combustor concept. Testing was conducted with ERBS petroleum distillate, petroleum residual, and SRC-II coal-derived liquid fuels over a range of operating conditions for the 12:1 pressure ratio General Electric MS7001E heavy-duty turbine. Blends of ERBS and SRC-II fuels were used to vary fuel properties over a wide range. In addition, pyridine was added to the ERBS and residual fuels to vary nitrogen level while holding other fuel properties constant. Test results indicate that low levels of NOx and fuel-bound nitrogen conversion can be achieved with the rich/lean combustor concepts for fuels with nitrogen contents up to 1.0% by weight. Multinozzle rich/lean Concept 2 demonstrated dry low Nox emissions within 10-15% of the EPA New Source Performance Standards goals for SRC-II fuel, with yields of approximately 15%, while meeting program goals for combustion efficiency, pressure drop, and exhaust gas temperature profile. Similar, if not superior, potential was demonstrated by Concept 3, which is a promising rich/lean combustor design.

"The largest Lean transformation in the world": the implementation and evaluation of lean in Saskatchewan healthcare.

PubMed

Kinsman, Leigh; Rotter, Thomas; Stevenson, Katherine; Bath, Brenna; Goodridge, Donna; Harrison, Liz; Dobson, Roy; Sari, Nazmi; Jeffery, Cathy; Bourassa, Carrie; Westhorp, Gill

2014-01-01

The Saskatchewan Ministry of Health has committed to a multi-million dollar investment toward the implementation of Lean methodology across the province's healthcare system. Originating as a production line discipline (the Toyota Production System), Lean has evolved to encompass process improvements including inventory management, waste reduction and quality improvement techniques. With an initial focus on leadership, strategic alignment, training and the creation of a supportive infrastructure (Lean promotion offices), the goal in Saskatchewan is a whole health system transformation that produces "better health, better value, better care, and better teams." Given the scope and scale of the initiative and the commitment of resources, it is vital that a comprehensive, longitudinal evaluation plan be implemented to support ongoing decision-making and program design. The nature of the initiative also offers a unique opportunity to contribute to health quality improvement science by advancing our understanding of the implementation and evaluation of complex, large-scale healthcare interventions. The purpose of this article is to summarize the background to Lean in Saskatchewan and the proposed evaluation methods. Copyright © 2014 Longwoods Publishing.

Ejector-Enhanced, Pulsed, Pressure-Gain Combustor

NASA Technical Reports Server (NTRS)

Paxson, Daniel E.; Dougherty, Kevin T.

2009-01-01

An experimental combination of an off-the-shelf valved pulsejet combustor and an aerodynamically optimized ejector has shown promise as a prototype of improved combustors for gas turbine engines. Despite their name, the constant pressure combustors heretofore used in gas turbine engines exhibit typical pressure losses ranging from 4 to 8 percent of the total pressures delivered by upstream compressors. In contrast, the present ejector-enhanced pulsejet combustor exhibits a pressure rise of about 3.5 percent at overall enthalpy and temperature ratios compatible with those of modern turbomachines. The modest pressure rise translates to a comparable increase in overall engine efficiency and, consequently, a comparable decrease in specific fuel consumption. The ejector-enhanced pulsejet combustor may also offer potential for reducing the emission of harmful exhaust compounds by making it practical to employ a low-loss rich-burn/quench/lean-burn sequence. Like all prior concepts for pressure-gain combustion, the present concept involves an approximation of constant-volume combustion, which is inherently unsteady (in this case, more specifically, cyclic). The consequent unsteadiness in combustor exit flow is generally regarded as detrimental to the performance of downstream turbomachinery. Among other adverse effects, this unsteadiness tends to detract from the thermodynamic benefits of pressure gain. Therefore, it is desirable in any intermittent combustion process to minimize unsteadiness in the exhaust path.

Laser ignition of engines: a realistic option!

NASA Astrophysics Data System (ADS)

Weinrotter, M.; Srivastava, D. K.; Iskra, K.; Graf, J.; Kopecek, H.; Klausner, J.; Herdin, G.; Wintner, E.

2006-01-01

Due to the demands of the market to increase efficiencies and power densities of gas engines, existing ignition schemes are gradually reaching their limits. These limitations initially triggered the development of laser ignition as an effective alternative, first only for gas engines and now for a much wider range of internal combustion engines revealing a number of immediate advantages like no electrode erosion or flame kernel quenching. Furthermore and most noteworthy, already the very first engine tests about 5 years ago had resulted in a drastic reduction of NO x emissions. Within this broad range investigation, laser plasmas were generated by ns Nd-laser pulses and characterized by emission and Schlieren diagnostic methods. High-pressure chamber experiments with lean hydrogen-methane-air mixtures were successfully performed and allowed the determination of essential parameters like minimum pulse energies at different ignition pressures and temperatures as well as at variable fuel air compositions. Multipoint ignition was studied for different ignition point locations. In this way, relevant parameters were acquired allowing to estimate future laser ignition systems. Finally, a prototype diode-pumped passively Q-switched Nd:YAG laser was tested successfully at a gasoline engine allowing to monitor the essential operation characteristics. It is expected that laser ignition involving such novel solid-state lasers will allow much lower maintenance efforts.

MSFC Electrostatic Levitator (ESL) Rapid Quench System

NASA Technical Reports Server (NTRS)

SanSoucie, Michael P.; Craven, Paul D.; Rogers, Jan R.

2014-01-01

The NASA Marshall Space Flight Center (MSFC) Electrostatic Levitator (ESL) Laboratory is a unique facility for investigators studying high-temperature materials. The laboratory boasts two levitators in which samples can be levitated, heated, melted, undercooled, and resolidified, all without the interference of a container or data-gathering instrument. The ESL main chamber has been upgraded with the addition of a rapid quench system. This system allows samples to be dropped into a quench vessel that can be filled with a low melting point material, such as a gallium or indium alloy. Thereby allowing rapid quenching of undercooled liquid metals. Up to 8 quench vessels can be loaded into the quench wheel, which is indexed with LabVIEW control software. This allows up to 8 samples to be rapidly quenched before having to open the chamber. The system has been tested successfully on several zirconium samples. Future work will be done with other materials using different quench mediums. Microstructural analysis will also be done on successfully quench samples.

Succesful Lean Manufacturing Implementation: Internal Key Influencing Factors

NASA Astrophysics Data System (ADS)

Virginia, Iuga; Claudiu, Kifor

2015-09-01

Manufacturing sectors and companies all over the world are successfully implementing lean principles within their processes. Nowadays, lean has become an indispensable part of global players. Companies worldwide need to be aware of multiple factors which weigh heavily on the success or failure of lean implementation. This paper focuses on giving a brief and structured overview over the fundamental organizational factors which play a substantial role for the lean manufacturing (LM) implementation process. The study below focuses on internal factors which are indispensable for a successful LM implementation within organizations. It is imperative that these internal factors are known, recognized and taken into consideration during the whole LM implementation process. Ignoring their influence on the process's implementation may lead to endangering the expected results or to making the process more difficult which could result in much higher human resource consumption.

The effect of lean manufacturing (LM) on environmental performance: A review study

NASA Astrophysics Data System (ADS)

Alaa, A. S.; Shaiful, A. I. M.; Zuraidah, M. Z.; Khalaf, A. M.

2017-09-01

Nowadays, lean manufacturing strategy is very much used to eliminate waste on the manufacturing shop floor. Lean manufacturing has been formulated in response to the fluctuating and competitive business environment. Although it first started in the automotive industry, many organizations in different sectors are enthusiastic to adopt it in order to improve their performance in this competitive globalized market. The aim of this paper is to review the current level of implementation of lean manufacturing practices and the affects of these practices on organizational performances in a multitude of sectors in Malaysian industries. The study is carried out through a thorough review of the literature. It is observed that lean manufacturing is increasingly getting the appropriate attention in Malaysian industries. There are also many challenges in the way, of which numerous attempts are undertaken to overcome them.

Spectroscopic studies on the interaction of fluorescein and safranine T in PC liposomes

NASA Astrophysics Data System (ADS)

Bozkurt, Ebru; Bayraktutan, Tuğba; Acar, Murat; Toprak, Mahmut

2013-01-01

In this study, the fluorescence quenching of fluorescein by safranine T in liposome media had been investigated systematically by fluorescence spectroscopy, UV-vis absorption spectroscopy and fluorescence decay lifetime measurements. The spectroscopic data were analyzed using a Stern-Volmer equation to determine the quenching process. The experimental results showed that the intrinsic fluorescence of fluorescein was strongly quenched by safranine T, and that the quenching mechanism was considered as static quenching by forming a ground-complex. The Stern-Volmer quenching constant Ksv, and the bimolecular quenching constant Kq were estimated. The distances between the donor (fluorescein) and the acceptor (safranine T) were calculated according to the Förster non-radiation energy transfer theory. In addition, the partition coefficient of the safranine T (Kp) in the L-egg lecithin phosphatidylcholine liposomes was also calculated by utilizing the fluorescence quenching.

Prior caloric restriction increases survival of prepubertal obese- and PCOS-prone rats exposed to a challenge of time-limited feeding and physical activity.

PubMed

Diane, Abdoulaye; Vine, Donna F; Heth, C Donald; Russell, James C; Proctor, Spencer D; Pierce, W David

2013-05-01

We hypothesized that a polycystic ovary syndrome (PCOS) background associated with obese-prone genotype, coupled with preconditioning by caloric restriction, would confer a survival benefit in genetically prepubertal obese/PCOS (O/PCOS)-prone rats faced with an unpredictable challenge of food shortage. Female, juvenile JCR:LA-cp rats, O/PCOS- and lean-prone, were exposed to 1.5 h of daily meals and 22.5 h of voluntary wheel-running, a procedure that leads to activity anorexia (AA). One week before the AA challenge (AAC), O/PCOS-prone rats were freely fed (O/PCOS-FF) or pair fed (O/PCOS-FR) to lean-prone, free-feeding animals (Lean-FF). O/PCOS-FR and lean-prone, food-restricted (Lean-FR) groups were matched on relative average caloric intake. Animals were removed from protocol at 75% of initial body weight (starvation criterion) or after 14 days (survival criterion). The AAC induced weight loss in all rats, but there were significant effects of both genotype and feeding history on weight loss (lean-prone rats exhibited a higher rate of weight loss than O/PCOS-prone; P < 0.001), and rats with prior caloric restriction retained more weight than those free fed previously (90.68 ± 0.59% vs. 85.47 ± 0.46%; P < 0.001). The daily rate of running was higher in lean-prone rats compared with O/PCOS-prone. This difference in running rate correlated with differences in mean days of survival. All O/PCOS-FR rats survived at day 14. O/PCOS-FF rats survived longer (10.00 ± 0.97 days) than Lean-FR (6.17 ± 1.58 days) and Lean-FF (4.33 ± 0.42 days) rats (P < 0.05). Thus preconditioning by caloric restriction induces a substantial survival advantage, beyond genotype alone, in prepubertal O/PCOS-prone rats.

Assessment of adult body composition using bioelectrical impedance: comparison of researcher calculated to machine outputted values.

PubMed

Franco-Villoria, Maria; Wright, Charlotte M; McColl, John H; Sherriff, Andrea; Pearce, Mark S

2016-01-07

To explore the usefulness of Bioelectrical Impedance Analysis (BIA) for general use by identifying best-evidenced formulae to calculate lean and fat mass, comparing these to historical gold standard data and comparing these results with machine-generated output. In addition, we explored how to best to adjust lean and fat estimates for height and how these overlapped with body mass index (BMI). Cross-sectional observational study within population representative cohort study. Urban community, North East England Sample of 506 mothers of children aged 7-8 years, mean age 36.3 years. Participants were measured at a home visit using a portable height measure and leg-to-leg BIA machine (Tanita TBF-300MA). Height, weight, bioelectrical impedance (BIA). Lean and fat mass calculated using best-evidenced published formulae as well as machine-calculated lean and fat mass data. Estimates of lean mass were similar to historical results using gold standard methods. When compared with the machine-generated values, there were wide limits of agreement for fat mass and a large relative bias for lean that varied with size. Lean and fat residuals adjusted for height differed little from indices of lean (or fat)/height(2). Of 112 women with BMI >30 kg/m(2), 100 (91%) also had high fat, but of the 16 with low BMI (<19 kg/m(2)) only 5 (31%) also had low fat. Lean and fat mass calculated from BIA using published formulae produces plausible values and demonstrate good concordance between high BMI and high fat, but these differ substantially from the machine-generated values. Bioelectrical impedance can supply a robust and useful field measure of body composition, so long as the machine-generated output is not used. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Antihypertensive effect of alpha- and beta-adrenergic blockade in obese and lean hypertensive subjects.

PubMed

Wofford, M R; Anderson, D C; Brown, C A; Jones, D W; Miller, M E; Hall, J E

2001-07-01

The purpose of this study was to determine the contribution of the adrenergic system in mediating hypertension in obese and lean patients. Thirteen obese, hypertensive patients with a body mass index (BMI) > or =28 kg/m2 (obese) and nine lean patients with a BMI < or =25 kg/m2 (lean) were recruited. After a 1-week washout period, participants underwent daytime ambulatory blood pressure monitoring (ABPM). Participants were then treated with the alpha-adrenergic antagonist doxazosin, titrating to 4 mg QHS in 1 week. In the next week, the beta-adrenergic antagonist atenolol was added at an initial dose of 25 mg/day and titrated to 50 mg/day within 1 week. One month after the addition of atenolol, all patients underwent a second ABPM session. There were no differences between the obese and lean subjects in baseline systolic (SBP), diastolic (DBP), or mean arterial pressures (MAP) measured by office recording or ABPM. However, obese subjects had higher heart rates than lean subjects (87.5+/-2.4 v 76.8+/-4.9 beats/min). After 1 month of treatment with the adrenergic blockers, obese patients had a significantly lower SBP (130.0+/-2.5 v 138.9+/-2.1 mm Hg, P = .02) and MAP (99.6+/-2.3 v 107.0+/-1.5 mm Hg, P = .02) than lean patients. Obese patients also tended to have a lower DBP than lean patients (84.3+/-2.5 v 90.9+/-1.6 mm Hg, P = .057), but there was no significant difference in heart rate after 1 month of adrenergic blockade. These results indicate that blood pressure is more sensitive to adrenergic blockade in obese than in lean hypertensive patients and suggest that increased sympathetic activity may be an important factor in the maintenance of hypertension in obesity.

Assessment of adult body composition using bioelectrical impedance: comparison of researcher calculated to machine outputted values

PubMed Central

Franco-Villoria, Maria; Wright, Charlotte M; McColl, John H; Sherriff, Andrea; Pearce, Mark S

2016-01-01

Objectives To explore the usefulness of Bioelectrical Impedance Analysis (BIA) for general use by identifying best-evidenced formulae to calculate lean and fat mass, comparing these to historical gold standard data and comparing these results with machine-generated output. In addition, we explored how to best to adjust lean and fat estimates for height and how these overlapped with body mass index (BMI). Design Cross-sectional observational study within population representative cohort study. Setting Urban community, North East England Participants Sample of 506 mothers of children aged 7–8 years, mean age 36.3 years. Methods Participants were measured at a home visit using a portable height measure and leg-to-leg BIA machine (Tanita TBF-300MA). Measures Height, weight, bioelectrical impedance (BIA). Outcome measures Lean and fat mass calculated using best-evidenced published formulae as well as machine-calculated lean and fat mass data. Results Estimates of lean mass were similar to historical results using gold standard methods. When compared with the machine-generated values, there were wide limits of agreement for fat mass and a large relative bias for lean that varied with size. Lean and fat residuals adjusted for height differed little from indices of lean (or fat)/height2. Of 112 women with BMI >30 kg/m2, 100 (91%) also had high fat, but of the 16 with low BMI (<19 kg/m2) only 5 (31%) also had low fat. Conclusions Lean and fat mass calculated from BIA using published formulae produces plausible values and demonstrate good concordance between high BMI and high fat, but these differ substantially from the machine-generated values. Bioelectrical impedance can supply a robust and useful field measure of body composition, so long as the machine-generated output is not used. PMID:26743700

Assessment of Lean Patients with Non-alcoholic Fatty Liver Disease in a Middle Income Country; Prevalence and Its Association with Metabolic Disorders: A Cross-sectional Study.

PubMed

Naderian, Mohammadreza; Kolahdoozan, Shadi; Sharifi, Amir Sina; Garmaroudi, Gholamreza; Yaseri, Mehdi; Poustchi, Hossein; Sohrabpour, Amir Ali

2017-04-01

Recent data has proven that the WHO (world health organization) cut-off for obesity is not applicable to the Asian population. This study aims to estimate the prevalence of lean NAFLD (non-alcoholic fatty liver disease) in the capital of Iran and extract probable predictors for this growing health issue in this population. This is a population-based cross-sectional study on apparently healthy subjects over 18 years of age. The participants were interviewed for baseline demographic and clinical information. They were subsequently referred for physical examination and blood sampling. NAFLD was diagnosed using abdominal ultrasonography by a single expert radiologist. Of 927 eligible participants who entered the study, 314 were lean; BMI (body mass index) <25 kg/m2. The prevalence of NAFLD was 17.52% (95% Exact CI: 13.48%-22.18%). BMI, SBP (systolic blood pressure), DBP (diastolic blood pressure), total cholesterol, HDL (high-density lipoprotein), LDL (low-density lipoprotein) and triglyceride were significantly different in patients with NAFLD. In the final multiple analysis, higher levels of triglyceride, upper SBP and higher BMI even in the range of less than 25 kg/m2 were independent predictors of NAFLD in lean participants. In lean participants with more components of metabolic syndrome, the prevalence of NAFLD increased significantly (all P < 0.01). BMI cut-offs in men and women along with waist circumference cut-off in men could significantly predict the presence of NAFLD in lean patients. After comparing these values, McNemar test showed that BMI cut-offs are more robust than waist circumference cut-offs for predicting the presence of NAFLD in lean subjects (P < 0.01). The prevalence of NAFLD in lean subjects in a sample of Iranian population is 17.52%. Hypertriglyceridemia, higher SBP, and higher BMI especially over 23.2 are independent factors associated with the presence of NAFLD in lean subjects.

Overweight adult cats have significantly lower voluntary physical activity than adult lean cats.

PubMed

de Godoy, Maria Rc; Shoveller, Anna K

2017-12-01

Objectives The objectives of the current pilot study were to evaluate whether body condition score (BCS) and body weight are significantly related to physical activity counts, and to evaluate potential interaction between BCS and voluntary physical activity measured over a 14 day period. Methods Ten (five lean, five overweight), neutered, adult American Shorthair cats were selected for this study (median age 4 ± 0.5 years). Cats with a BCS of ⩽3.0 were considered lean, whereas cats with a BCS >3.0 were considered overweight, using a 5-point scale. Cats were housed in a free-living environment with indoor/outdoor access and were individually fed once daily a commercially available dry extruded diet and allowed 1 h to eat. Voluntary physical activity was measured consecutively for 14 days using the Actical Activity Monitors that were worn parallel to the ribs and attached via a harness. Results Lean cats had a greater mean total daily voluntary physical activity ( P = 0.0059), and a greater voluntary physical activity during light ( P = 0.0023) and dark ( P = 0.0446) periods, with overweight cats having 60% of the physical activity of lean cats. Lean cats were more active before feeding and during animal care procedures. These data suggest that lean cats have a greater anticipatory physical activity prior to feeding and are more eager to have social interaction with humans than overweight cats. A significant interaction was observed between day of physical activity measurement and BCS for total daily voluntary physical activity ( P = 0.0133) and activity during the light period ( P = 0.0016) where lean cats were consistently more active than overweight cats. In general, cats were more active during weekdays vs weekends. Conclusions and relevance The results of this study suggest that overweight cats are less active than lean cats and that voluntary physical activity level appears to be influenced by social interaction with humans.

Down-regulation of hypothalamic pro-opiomelanocortin (POMC) expression after weaning is associated with hyperphagia-induced obesity in JCR rats overexpressing neuropeptide Y.

PubMed

Diané, Abdoulaye; Pierce, W David; Russell, James C; Heth, C Donald; Vine, Donna F; Richard, Denis; Proctor, Spencer D

2014-03-14

We hypothesised that hypothalamic feeding-related neuropeptides are differentially expressed in obese-prone and lean-prone rats and trigger overeating-induced obesity. To test this hypothesis, in the present study, we measured energy balance and hypothalamic neuropeptide Y (NPY) and pro-opiomelanocortin (POMC) mRNA expressions in male JCR:LA-cp rats. We compared, in independent cohorts, free-feeding obese-prone (Obese-FF) and lean-prone (Lean-FF) rats at pre-weaning (10 d old), weaning (21-25 d old) and early adulthood (8-12 weeks). A group of Obese-pair-feeding (PF) rats pair-fed to the Lean-FF rats was included in the adult cohort. The body weights of 10-d-old Obese-FF and Lean-FF pups were not significantly different. However, when the pups were shifted from dams' milk to solid food (weaning), the obese-prone rats exhibited more energy intake over the days than the lean-prone rats and higher body and fat pad weights and fasting plasma glucose, leptin, insulin and lipid levels. These differences were consistent with higher energy consumption and lower energy expenditure. In the young adult cohort, the differences between the Obese-FF and Lean-FF rats became more pronounced, yielding significant age effects on most of the parameters of the metabolic syndrome, which were reduced in the Obese-PF rats. The obese-prone rats displayed higher NPY expression than the lean-prone rats at pre-weaning and weaning, and the expression levels did not differ by age. In contrast, POMC expression exhibited significant age-by-genotype differences. At pre-weaning, there was no genotype difference in POMC expression, but in the weanling cohort, obese-prone pups exhibited lower POMC expression than the lean-prone rats. This genotype difference became more pronounced at adulthood. Overall, the development of hyperphagia-induced obesity in obese-prone JCR rats is related to POMC expression down-regulation in the presence of established NPY overexpression.

Lean, premixed, prevaporized combustion for aircraft gas turbine engines

NASA Technical Reports Server (NTRS)

Mularz, E. J.

1979-01-01

The application of lean, premixed, prevaporized combustion to aircraft turbine engine systems can result in benefits in terms of superior combustion performance, improved combustor and turbine durability, and environmentally acceptable pollutant emissions. Lean, premixed prevaporized combustion is particularly attractive for reducing the oxides of nitrogen emissions during high altitude cruise. The NASA stratospheric cruise emission reduction program will evolve and demonstrate lean, premixed, prevaporized combustion technology for aircraft engines. This multiphased program is described. In addition, the various elements of the fundamental studies phase of the program are reviewed, and results to date of many of these studies are summarized.

Lean Management as an Instrument of Sustainable Development of Enterprises

NASA Astrophysics Data System (ADS)

Sikora, Marcin; Kwiatkowski, Maciej; Prosół, Hanna; Nowicka, Daria; Lorenc, Karolina; Pham, Laurena

2016-03-01

The aim of the paper is to present the philosophy of Lean Management as an instrument of improving sustainable management of enterprises. The article presents the origins, characteristics of the broadly understood concept of Lean Management and describes the idea of Sustainable Development (SD). At the same time implications for the application and development of the instruments which operationalize the assumptions of SD at the level of enterprises are discussed. The paper specifies those areas of functioning of contemporary companies in which Lean Management can be implemented and compares them with the features of traditional management in particular subjects.

Clinically lean; "cutting the crap".

PubMed

Caldwell, G

2012-01-01

Proponents of Lean Philosophy believe that successful businesses must reduce waste in working time and resources to a minimum, and maximise their use in productive work. The productive work of the Acute Medical Unit is to provide effective clinical management to a daily cohort of acutely ill patients. Many Clinicians are cynical about Lean. In this article, Dr Caldwell discusses how many clinicians complain of too much crap in the workplace, which gets in the way of swift, safe high quality clinical care. He argues that "Cutting the Crap" in the Acute Medical Unit is entirely consistent with Lean approaches to management of complex systems.

Improving healthcare using Lean processes.

PubMed

Baker, G Ross

2014-01-01

For more than a decade, healthcare organizations across Canada have been using Lean management tools to improve care processes, reduce preventable adverse events, increase patient satisfaction and create better work environments. The largest system-wide effort in Canada, and perhaps anywhere, is currently under way in Saskatchewan. The jury is still out on whether Lean efforts in that province, or elsewhere in Canada, are robust enough to transform current delivery systems and sustain new levels of performance. This issue of Healthcare Quarterly features several articles that provide a perspective on Lean methods in healthcare. Copyright © 2014 Longwoods Publishing.

STS-52 MS Veach and Payload Specialist MacLean during JSC bailout exercises

NASA Technical Reports Server (NTRS)

1992-01-01

STS-52 Columbia, Orbiter Vehicle (OV) 102, Mission Specialist (MS) Charles Lacy Veach (left) and Canadian Payload Specialist Steven G. MacLean listen to a briefing during emergency egress (bailout) training exercises in JSC's Weightless Environment Training Facility (WETF) Bldg 29. Veach and MacLean are fully outfitted in launch and entry suits (LESs), launch and entry helmets (LEHs), parachutes, and water survival equipment including a life jacket. The WETF's 25-ft deep pool will simulate the ocean as the crewmember's prepare for the event of a water landing. MacLean represents the Canadian Space Agency (CSA).

[Physical exercise is a help for lean women with polycystic ovary syndrome].

PubMed

Bisgaard, Helene; Dela, Flemming

2017-06-05

Polycystic ovary syndrome (PCOS) affects 12-21% of women in the childbearing age and is the most common cause of hyperandrogenaemia and anovulatory infertility. There is an increase in insulin resistance in both overweight and lean women with PCOS. Exercise treatment is mandatory among the overweight women due to sufficient evidence that it can improve the signs and symptoms of PCOS. This has not been fully investigated among the lean. However, new randomized controlled trials show that structured physical exercise can also improve insulin sensitivity, hyperandrogenaemia and menstrual frequency in lean women with PCOS.

Assessment of insulin resistance in lean women with polycystic ovary syndrome.

PubMed

Morciano, Andrea; Romani, Federica; Sagnella, Francesca; Scarinci, Elisa; Palla, Carola; Moro, Francesca; Tropea, Anna; Policola, Caterina; Della Casa, Silvia; Guido, Maurizio; Lanzone, Antonio; Apa, Rosanna

2014-07-01

To develop and validate a specific simple measure of insulin sensitivity using oral glucose tolerance test (OGTT) values for lean polycystic ovary syndrome (PCOS) women. Retrospective study. Gynecologic Outpatient Clinic of University Hospital, affiliated with Unit of Gynecologic Endocrinology. Totals of 201 lean and 198 overweight/obese (ov-ob) nondiabetic PCOS patients were retrospectively selected. None. All patients underwent OGTT, euglycemic-hyperinsulinemic clamp, and androgenic and biochemical assays. The predictive performance of each insulin resistance (IR) index was analyzed with the use of receiver operating characteristic (ROC) curves. Higher correlation coefficients with clamp studies were obtained with the Belfiore Area (RS=0.579) and the homeostasis-model assessment (HOMA)-M120 (RS=-0.576) in lean PCOS patients and with the Sib (RS=0.697) in ov-ob PCOS patients. The best predictive index of IR in lean PCOS was a HOMA-M120 value of ≥12.8 or more (area under the ROC curve [AUC] 92.4%). In the ov-ob PCOS population, the best predictive performance was obtained by a Sib of ≤10.2 or less (AUC 85.7%). IR should be assessed in all PCOS women, both lean and ov-ob subjects. The HOMA-M120 resulted as a very simple tool, validated specifically for the lean PCOS woman whose cardiometabolic impairment is more frequently misunderstood. Copyright © 2014 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

Effect of acute ozone exposure on the lung metabolomes of obese and lean mice.

PubMed

Mathews, Joel Andrew; Kasahara, David Itiro; Cho, Youngji; Bell, Lauren Nicole; Gunst, Philip Ross; Karoly, Edward D; Shore, Stephanie Ann

2017-01-01

Pulmonary responses to the air pollutant, ozone, are increased in obesity. Both obesity and ozone cause changes in systemic metabolism. Consequently, we examined the impact of ozone on the lung metabolomes of obese and lean mice. Lean wildtype and obese db/db mice were exposed to acute ozone (2 ppm for 3 h) or air. 24 hours later, the lungs were excised, flushed with PBS to remove blood and analyzed via liquid-chromatography or gas-chromatography coupled to mass spectrometry for metabolites. Both obesity and ozone caused changes in the lung metabolome. Of 321 compounds identified, 101 were significantly impacted by obesity in air-exposed mice. These included biochemicals related to carbohydrate and lipid metabolism, which were each increased in lungs of obese versus lean mice. These metabolite changes may be of functional importance given the signaling capacity of these moieties. Ozone differentially affected the lung metabolome in obese versus lean mice. For example, almost all phosphocholine-containing lysolipids were significantly reduced in lean mice, but this effect was attenuated in obese mice. Glutathione metabolism was also differentially affected by ozone in obese and lean mice. Finally, the lung metabolome indicated a role for the microbiome in the effects of both obesity and ozone: all measured bacterial/mammalian co-metabolites were significantly affected by obesity and/or ozone. Thus, metabolic derangements in obesity appear to impact the response to ozone.

Illusion or delusion--Lean management in the health sector.

PubMed

McIntosh, Bryan; Sheppy, Bruce; Cohen, Ivan

2014-01-01

There has been considerable interest in the implementation of practices imported from manufacturing into healthcare as a solution to rising healthcare spending and disappointing patient safety indicators. One approach that has attracted particular interest is Lean management and the purpose of this paper is to engage with this topic. Secondary research. Despite widespread enthusiasm about the potential of Lean management processes, evidence about its contribution to higher organisational performance remains inconsistent. This paper engages with the major Lean concepts of operations management and human resource management, including just-in-time, total quality management, total productive maintenance and does not engage in-depth with concepts related to employee empowerment, and training This paper contributes to the organisational management literature in healthcare by showing that although Lean management seems to have the potential to improve organisational performance it is far from a panacea against under performing hospitals. It informs policy making by suggesting that a progressive managerial philosophy has a stronger impact on healthcare performance than the adoption of practices from any particular managerial approach. This paper provides a critical evaluation of the impact of Lean practices in informing healthcare policy. The paper contributes to the organisational management literature in healthcare by showing that even though Lean management in healthcare appears to have the potential to improve organisational performance; there remain problems with its application.

Effect of Caloric Restriction and AMPK Activation on Hepatic Nuclear Receptor, Biotransformation Enzyme, and Transporter Expression in Lean and Obese Mice

PubMed Central

Kulkarni, Supriya R.; Xu, Jialin; Donepudi, Ajay C.; Wei, Wei

2014-01-01

Purpose Fatty liver alters liver transporter expression. Caloric restriction (CR), the recommended therapy to reverse fatty liver, increases Sirtuin1 deacetylase activity in liver. This study evaluated whether CR and CR mimetics reversed obesity-induced transporter expression in liver and hepatocytes. Methods mRNA and protein expression was determined in adult lean (lean) and leptin-deficient obese (OB) mice fed ad libitum or placed on 40% (kCal) reduced diet. Hepatocytes were isolated from lean and OB mice, treated with AMP Kinase activators, and gene expression was determined. Results CR decreased Oatp1a1, Oatp1b2, and Abcb11 mRNA expression in lean, but not OB mice. CR increased Abcc2 mRNA OB livers, whereas protein expression increased in both genotypes. CR increased Abcc3 protein expression increased in OB livers. CR did not alter Abcc1, 4 and 5 mRNA expression in lean mice but decreased expression in livers of OB mice. CR increased Abcc4 protein in lean, but not OB mice. Conclusions CR restriction reversed the expression of some, but not all transporters in livers of OB mice. Overall, these data indicate a potential for CR to restore some hepatic transporter changes in OB mice, but suggest a functional leptin axis is needed for reversal of expression for some transporters. PMID:23949303

Improving the medical records department processes by lean management.

PubMed

Ajami, Sima; Ketabi, Saeedeh; Sadeghian, Akram; Saghaeinnejad-Isfahani, Sakine

2015-01-01

Lean management is a process improvement technique to identify waste actions and processes to eliminate them. The benefits of Lean for healthcare organizations are that first, the quality of the outcomes in terms of mistakes and errors improves. The second is that the amount of time taken through the whole process significantly improves. The purpose of this paper is to improve the Medical Records Department (MRD) processes at Ayatolah-Kashani Hospital in Isfahan, Iran by utilizing Lean management. This research was applied and an interventional study. The data have been collected by brainstorming, observation, interview, and workflow review. The study population included MRD staff and other expert staff within the hospital who were stakeholders and users of the MRD. The MRD were initially taught the concepts of Lean management and then formed into the MRD Lean team. The team then identified and reviewed the current processes subsequently; they identified wastes and values, and proposed solutions. The findings showed that the MRD units (Archive, Coding, Statistics, and Admission) had 17 current processes, 28 wastes, and 11 values were identified. In addition, they offered 27 comments for eliminating the wastes. The MRD is the critical department for the hospital information system and, therefore, the continuous improvement of its services and processes, through scientific methods such as Lean management, are essential. The study represents one of the few attempts trying to eliminate wastes in the MRD.

Lean management systems: creating a culture of continuous quality improvement.

PubMed

Clark, David M; Silvester, Kate; Knowles, Simon

2013-08-01

This is the first in a series of articles describing the application of Lean management systems to Laboratory Medicine. Lean is the term used to describe a principle-based continuous quality improvement (CQI) management system based on the Toyota production system (TPS) that has been evolving for over 70 years. Its origins go back much further and are heavily influenced by the work of W Edwards Deming and the scientific method that forms the basis of most quality management systems. Lean has two fundamental elements--a systematic approach to process improvement by removing waste in order to maximise value for the end-user of the service and a commitment to respect, challenge and develop the people who work within the service to create a culture of continuous improvement. Lean principles have been applied to a growing number of Healthcare systems throughout the world to improve the quality and cost-effectiveness of services for patients and a number of laboratories from all the pathology disciplines have used Lean to shorten turnaround times, improve quality (reduce errors) and improve productivity. Increasingly, models used to plan and implement large scale change in healthcare systems, including the National Health Service (NHS) change model, have evidence-based improvement methodologies (such as Lean CQI) as a core component. Consequently, a working knowledge of improvement methodology will be a core skill for Pathologists involved in leadership and management.

Utilizing lean tools to improve value and reduce outpatient wait times in an Indian hospital.

PubMed

Miller, Richard; Chalapati, Nirisha

2015-01-01

This paper aims to demonstrate how lean tools were applied to some unique issues of providing healthcare in a developing country where many patients face challenges not found in developed countries. The challenges provide insight into how lean tools can be utilized to provide similar results across the world. This paper is based on a qualitative case study carried out by a master's student implementing lean at a hospital in India. This paper finds that lean tools such as value-stream mapping and root cause analysis can lead to dramatic reductions in waste and improvements in productivity. The problems of the majority of patients paying for their own healthcare and lacking transportation created scheduling problems that required patients to receive their diagnosis and pay for treatment within a single day. Many additional wastes were identified that were significantly impacting the hospital's ability to provide care. As a result of this project, average outpatient wait times were reduced from 1 hour to 15 minutes along with a significant increase in labor productivity. The results demonstrate how lean tools can increase value to the patients. It also provides are framework that can be utilized for healthcare providers in developed and developing countries to analyze their value streams to reduce waste. This paper is one of the first to address the unique issues of implementing lean to a healthcare setting in a developing country.

Effect of lean red meat from lamb v. lean white meat from chicken on the serum lipid profile: a randomised, cross-over study in women.

PubMed

Mateo-Gallego, Rocio; Perez-Calahorra, Sofia; Cenarro, Ana; Bea, Ana M; Andres, Eva; Horno, Jaime; Ros, Emilio; Civeira, Fernando

2012-05-01

The main dietary guidelines recommend restricting total and saturated fat intake in the management of high blood cholesterol levels for cardiovascular risk. These recommendations are usually oversimplified by considering that all red meats should be limited and replaced by white meats. However, lean red meat can be as low in fat as white meat. We examined the effects of red meat (lean breed lamb) and lean white meat (chicken) intake on the lipid profile of a group of women with stable life conditions (nuns living in convents). An open-label, randomised, cross-over study was carried out in thirty-six nuns who consumed either lamb or chicken three times per week for 5-week periods with their usual diet. Clinical, dietary and biochemical variables were evaluated at baseline and the end of each diet period. A validated FFQ was used to assess nutrient intake and monitor compliance. The results showed neither between-diet differences in lipid responses nor differences from baseline in total cholesterol, LDL-cholesterol or TAG for any diet period. In conclusion, consumption of lean red meat (lamb) or lean white meat (chicken) as part of the usual diet is associated with a similar lipid response. These two foods can be exchanged in a healthy diet to increase palatability.

High sensitivity C-reactive protein and its relationship with impaired glucose regulation in lean patients with polycystic ovary syndrome.

PubMed

Kim, Ji Won; Han, Ji Eun; Kim, You Shin; Won, Hyung Jae; Yoon, Tae Ki; Lee, Woo Sik

2012-04-01

The polycystic ovary syndrome (PCOS) is the most common endocrine-metabolic disorder, also associated with the metabolic syndrome. Serum high sensitivity C-reactive protein (hs-CRP), a marker of low-grade chronic inflammation is a potent predictor of cardiovascular events, closely linked to metabolic syndrome features and higher in patients with PCOS. However, hs-CRP in lean patients with PCOS has not been fully evaluated and few data are available. We aimed to investigate the relation between glucose intolerance and hs-CRP levels in lean patients with PCOS, and to evaluate the possible relationship between hs-CRP and PCOS by evaluating PCOS-related metabolic abnormalities in Korean women. We consecutively recruited 115 lean (BMI < 25kg/m(2)) patients diagnosed with PCOS and 103 lean healthy controls. The PCOS group was divided two groups: impaired glucose regulation (IGR) and normal glucose tolerance group (NGT). In lean patients with PCOS, hs-CRP level was higher in the IGR group than in the NGT group (0.60 ± 1.37 versus 0.18 ± 0.46, p(Bonf) = 0.023) and other metabolic risk factors were also higher in the IGR group than in the NGT group. And there were close relationships between hs-CRP level and metabolic risk factor, such as 2 h postprandial insulin level in the lean patients with PCOS.

A Value Analysis of Lean Processes in Target Value Design and Integrated Project Delivery.

PubMed

Nanda, Upali; K Rybkowski, Zofia; Pati, Sipra; Nejati, Adeleh

2017-04-01

To investigate what key stakeholders consider to be the advantages and the opportunities for improvement in using lean thinking and tools in the integrated project delivery (IPD) process. A detailed literature review was followed by case study of a Lean-IPD project. Interviews with members of the project leadership team, focus groups with the integrated team as well as the design team, and an online survey of all stakeholders were conducted. Statistical analysis and thematic content analysis were used to analyze the data, followed by a plus-delta analysis. (1) Learning is a large, implicit benefit of Lean-IPD that is not currently captured by any success metric; (2) the cardboard mock-up was the most successful lean strategy; (3) although a collaborative project, the level of influence of different stakeholder groups was perceived to be different by different stakeholders; (4) overall, Lean-IPD was rated as better than traditional design-bid-build methods; and (5) opportunities for improvement reported were increase in accurate cost estimating, more efficient use of time, perception of imbalance of control/influence, and need for facilitation (which represents different points of view). While lean tools and an IPD method are preferred to traditional design-bid-build methods, the perception of different stakeholders varies and more work needs to be done to allow a truly shared decision-making model. Learning was identified as one of the biggest advantages.

Qualitative Examination of Strategies to Overcome Resistance to Change in Lean Manufacturing

ERIC Educational Resources Information Center

Burmester, Elizabeth

2017-01-01

Approximately 80% of lean manufacturing program initiatives are abandoned in the first year of implementation. Only 2% of organizations that embark on the lean journey complete it with the results and the sustainability they expected. There is a gap in past research regarding, the leadership strategies organizations can use to overcome resistance…

Comparing Textbook Coverage of Lean Management to Academic Research and Industry Practitioner Perceptions

ERIC Educational Resources Information Center

Marley, Kathryn A.; Stodnick, T. Michael; Heyl, Jeff

2013-01-01

Within operations management courses, most instructors choose to devote classroom time to teaching the topic of lean management. However, because the amount of time available for instructors to devote to this topic varies considerably, there is a great deal of latitude on which specific lean tools and techniques should be discussed. The authors…

Fat and Lean Masses in Youths with Down Syndrome: Gender Differences

ERIC Educational Resources Information Center

Gonzalez-Aguero, Alejandro; Ara, Ignacio; Moreno, Luis A.; Vicente-Rodriguez, German; Casajus, Jose A.

2011-01-01

The present study aimed at comparing fat and lean masses between children and adolescents with and without Down syndrome (DS) and evaluating the presence of sexual dimorphism. Total and regional fat and lean masses were assessed by dual energy X-ray absorptiometry (DXA) and the percentage of body fat (%BF) by air-displacement plethysmography (ADP)…

Caloric Restriction in Lean and Obese Strains of Laboratory Rat: Effects on Body Composition, Metabolism, Growth, and Overall Health

EPA Science Inventory

NEW FINDINGS: What is the central question of this study? How do lean and obese rats respond physiologically to caloric restriction? What is the main finding and its importance? Obese rats show marked benefits compared with lean animals. Reduced body fat is associated with improv...

The Work of Glendon Lean on the Counting Systems of Papua New Guinea and Oceania.

ERIC Educational Resources Information Center

Owens, Kay

2001-01-01

Introduces data collated by Glendon Lean on nearly 900 counting systems in Papua New Guinea, Oceania, and Irian Jaya (West Papua) which came from a questionnaire completed by students and talks with village elders. Lean's thesis on the spontaneous developments of these ancient cultures challenged traditional theories describing the spread of…

Teaching Lean Six Sigma within a Supply Chain Context: The Airplane Supply Chain Simulation

ERIC Educational Resources Information Center

Ellis, Scott C.; Goldsby, Thomas J.; Bailey, Ana M.; Oh, Jae-Young

2014-01-01

Lean six sigma is a management methodology that firms can employ to achieve substantial improvement in supply chain performance. However, few pedagogical exercises facilitate students' use of a comprehensive set of lean six sigma principles within a supply chain context. We describe the Airplane Supply Chain Simulation that helps students…

Applying Lean Six Sigma for innovative change to the post-anesthesia care unit.

PubMed

Haenke, Roger; Stichler, Jaynelle F

2015-04-01

Many healthcare organizations are building or renovating patient care facilities. Using Lean Six Sigma methods, nurse leaders can eliminate unnecessary waste and improve work and patient care environments. Starting with a key department like the post-anesthesia care unit is a good way to expose staff and leaders to the potential of Lean.

Novel lean type 2 diabetic rat model using gestational low-protein programming

USDA-ARS?s Scientific Manuscript database

Type 2 diabetes (T2D) in lean individuals is not well studied and up to 26% of diabetes occurs in these individuals. Although the cause is not well understood, it has been primarily attributed to nutritional issues during early development. Our objective was to develop a lean T2D model using gestati...

Facilitating Teamwork with Lean Six Sigma and Web-Based Technology

ERIC Educational Resources Information Center

Krause, Tim

2009-01-01

In this article, the author outlines a variety of ways of defining, making explicit, and supporting effective team-based projects through the basic tenets of Lean Six Sigma and the use of Web-based technologies. A combination of Lean Six Sigma and a handful of project management technologies not only help in fostering the communication central to…

Review of thermo-physical properties, wetting and heat transfer characteristics of nanofluids and their applicability in industrial quench heat treatment

PubMed Central

2011-01-01

The success of quenching process during industrial heat treatment mainly depends on the heat transfer characteristics of the quenching medium. In the case of quenching, the scope for redesigning the system or operational parameters for enhancing the heat transfer is very much limited and the emphasis should be on designing quench media with enhanced heat transfer characteristics. Recent studies on nanofluids have shown that these fluids offer improved wetting and heat transfer characteristics. Further water-based nanofluids are environment friendly as compared to mineral oil quench media. These potential advantages have led to the development of nanofluid-based quench media for heat treatment practices. In this article, thermo-physical properties, wetting and boiling heat transfer characteristics of nanofluids are reviewed and discussed. The unique thermal and heat transfer characteristics of nanofluids would be extremely useful for exploiting them as quench media for industrial heat treatment. PMID:21711877

Review of thermo-physical properties, wetting and heat transfer characteristics of nanofluids and their applicability in industrial quench heat treatment.

PubMed

Ramesh, Gopalan; Prabhu, Narayan Kotekar

2011-04-14

The success of quenching process during industrial heat treatment mainly depends on the heat transfer characteristics of the quenching medium. In the case of quenching, the scope for redesigning the system or operational parameters for enhancing the heat transfer is very much limited and the emphasis should be on designing quench media with enhanced heat transfer characteristics. Recent studies on nanofluids have shown that these fluids offer improved wetting and heat transfer characteristics. Further water-based nanofluids are environment friendly as compared to mineral oil quench media. These potential advantages have led to the development of nanofluid-based quench media for heat treatment practices. In this article, thermo-physical properties, wetting and boiling heat transfer characteristics of nanofluids are reviewed and discussed. The unique thermal and heat transfer characteristics of nanofluids would be extremely useful for exploiting them as quench media for industrial heat treatment.

The effects of short-term overfeeding on insulin action in lean and reduced-obese individuals.

PubMed

Cornier, Marc-Andre; Bergman, Bryan C; Bessesen, Daniel H

2006-09-01

Insulin resistance is clearly associated with obesity. However, the role of excess energy intake per se as opposed to increased fat mass in the development of insulin resistance has not been clearly defined. It may be that the nutrient load provided by short-term overfeeding is sufficient to induce measurable changes in insulin action in skeletal muscle and the liver. We examined the effects of 3 days of overfeeding on insulin action and glucose kinetics in 13 lean (body mass index, 20.9 +/- 2.4 kg/m(2); 6 men, 7 women) and 9 reduced-obese (RO) (body mass index, 29.1 +/- 2.2 kg/m(2); 4 men, 5 women) individuals. A two-step euglycemic hyperinsulinemic clamp study (5 and 40 mU m(-2) min(-1)) with a primed, constant infusion of [6,6-(2)H(2)]glucose was performed after 3 days of a weight-maintenance diet and again after 3 days of overfeeding by 50% (50% carbohydrate, 30% fat, 20% protein). At baseline, lean individuals were more insulin sensitive, as measured by glucose infusion rate, than RO individuals (12.08 +/- 0.8 vs 7.62 +/- 1.0 mg x kg(-1) x min(-1), P < .01) with lean women being more insulin sensitive than lean men (P < .01). Overfeeding resulted in a reduction in glucose infusion rate in lean women (13.37 +/- 1.3 to 11.42 +/- 1.0 mg x kg(-1) x min(-1), P < .05), but no change was noted in lean men or RO individuals. Basal and insulin-stimulated glucose disposal remained unchanged with overfeeding in all groups. Low-dose insulin suppression of endogenous glucose production was impaired after overfeeding in lean women (euenergetic, 1.92 +/- 0.36 to 0.36 +/- 0.16 mg x kg(-1) x min(-1); overfeeding: 2.13 +/- 0.17 to 0.86 +/- 0.12 mg x kg(-1) x min(-1); P = .04) but remained unchanged in the other groups. These findings demonstrate that insulin action is reduced in lean, obese-resistant women after short-term overfeeding primarily because of an inhibition of insulin-mediated suppression of endogenous glucose production, whereas short-term overfeeding does not appear to effect insulin action in lean men and RO individuals. This response may be indirectly involved in the ability of lean women to maintain weight in the face of an obesigenic environment.

High-fat diet-induced obesity leads to increased NO sensitivity of rat coronary arterioles: role of soluble guanylate cyclase activation.

PubMed

Jebelovszki, Eva; Kiraly, Csaba; Erdei, Nora; Feher, Attila; Pasztor, Eniko T; Rutkai, Ibolya; Forster, Tamas; Edes, Istvan; Koller, Akos; Bagi, Zsolt

2008-06-01

The impact of obesity on nitric oxide (NO)-mediated coronary microvascular responses is poorly understood. Thus NO-mediated vasomotor responses were investigated in pressurized coronary arterioles ( approximately 100 microm) isolated from lean (on normal diet) and obese (fed with 60% of saturated fat) rats. We found that dilations to acetylcholine (ACh) were not significantly different in obese and lean rats (lean, 83 +/- 4%; and obese, 85 +/- 3% at 1 microM), yet the inhibition of NO synthesis with N(omega)-nitro-l-arginine methyl ester reduced ACh-induced dilations only in vessels of lean controls. The presence of the soluble guanylate cyclase (sGC) inhibitor oxadiazolo-quinoxaline (ODQ) elicited a similar reduction in ACh-induced dilations in the two groups of vessels (lean, 60 +/- 11%; and obese, 57 +/- 3%). Dilations to NO donors, sodium nitroprusside (SNP), and diethylenetriamine (DETA)-NONOate were enhanced in coronary arterioles of obese compared with lean control rats (lean, 63 +/- 6% and 51 +/- 5%; and obese, 78 +/- 5% and 70 +/- 5%, respectively, at 1 microM), whereas dilations to 8-bromo-cGMP were not different in the two groups. In the presence of ODQ, both SNP and DETA-NONOate-induced dilations were reduced to a similar level in lean and obese rats. Moreover, SNP-stimulated cGMP immunoreactivity in coronary arterioles and also cGMP levels in carotid arteries were enhanced in obese rats, whereas the protein expression of endothelial NOS and the sGC beta1-subunit were not different in the two groups. Collectively, these findings suggest that in coronary arterioles of obese rats, the increased activity of sGC leads to an enhanced sensitivity to NO, which may contribute to the maintenance of NO-mediated dilations and coronary perfusion in obesity.

The lean service machine.

PubMed

Swank, Cynthia Karen

2003-10-01

Jefferson Pilot Financial, a life insurance and annuities firm, like many U.S. service companies at the end of the 1990s was looking for new ways to grow. Its top managers recognized that JPF needed to differentiate itself in the eyes of its customers, the independent life-insurance advisers who sell and service policies. To establish itself as these advisers' preferred partner, it set out to reduce the turnaround time on policy applications, simplify the submission process, and reduce errors. JPF's managers looked to the "lean production" practices that U.S. manufacturers adopted in response to competition from Japanese companies. Lean production is built around the concept of continuous-flow processing--a departure from traditional production systems, in which large batches are processed at each step. JPF appointed a "lean team" to reengineer its New Business unit's operations, beginning with the creation of a "model cell"--a fully functioning microcosm of JPF's entire process. This approach allowed managers to experiment and smooth out the kinks while working toward an optimal design. The team applied lean-manufacturing practices, including placing linked processes near one another, balancing employees' workloads, posting performance results, and measuring performance and productivity from the customer's perspective. Customer-focused metrics helped erode the employees' "My work is all that matters" mind-set. The results were so impressive that JPF is rolling out similar systems across many of its operations. To convince employees of the value of lean production, the lean team introduced a simulation in which teams compete to build the best paper airplane based on invented customer specifications. This game drives home lean production's basic principles, establishing a foundation for deep and far-reaching changes in the production system.

Validation of a quantitative magnetic resonance method for measuring human body composition.

PubMed

Napolitano, Antonella; Miller, Sam R; Murgatroyd, Peter R; Coward, W Andrew; Wright, Antony; Finer, Nick; De Bruin, Tjerk W; Bullmore, Edward T; Nunez, Derek J

2008-01-01

To evaluate a novel quantitative magnetic resonance (QMR) methodology (EchoMRI-AH, Echo Medical Systems) for measurement of whole-body fat and lean mass in humans. We have studied (i) the in vitro accuracy and precision by measuring 18 kg Canola oil with and without 9 kg water (ii) the accuracy and precision of measures of simulated fat mass changes in human subjects (n = 10) and (iii) QMR fat and lean mass measurements compared to those obtained using the established 4-compartment (4-C) model method (n = 30). (i) QMR represented 18 kg of oil at 40 degrees C as 17.1 kg fat and 1 kg lean while at 30 degrees C 15.8 kg fat and 4.7 kg lean were reported. The s.d. of repeated estimates was 0.13 kg for fat and 0.23 kg for lean mass. Adding 9 kg of water reduced the fat estimates, increased misrepresentation of fat as lean, and degraded the precision. (ii) the simulated change in the fat mass of human volunteers was accurately represented, independently of added water. (iii) compared to the 4-C model, QMR underestimated fat and over-estimated lean mass. The extent of difference increased with body mass. The s.d. of repeated measurements increased with adiposity, from 0.25 kg (fat) and 0.51 kg (lean) with BMI <25 kg/m(2) to 0.43 kg and 0.81 kg respectively with BMI >30 kg/m(2). EchoMRI-AH prototype showed shortcomings in absolute accuracy and specificity of fat mass measures, but detected simulated body composition change accurately and with precision roughly three times better than current best measures. This methodology should reduce the study duration and cohort number needed to evaluate anti-obesity interventions.

Lean methodology for performance improvement in the trauma discharge process.

PubMed

O'Mara, Michael Shaymus; Ramaniuk, Aliaksandr; Graymire, Vickie; Rozzell, Monica; Martin, Stacey

2014-07-01

High-volume, complex services such as trauma and acute care surgery are at risk for inefficiency. Lean process improvement can reduce health care waste. Lean allows a structured look at processes not easily amenable to analysis. We applied lean methodology to the current state of communication and discharge planning on an urban trauma service, citing areas for improvement. A lean process mapping event was held. The process map was used to identify areas for immediate analysis and intervention-defining metrics for the stakeholders. After intervention, new performance was assessed by direct data evaluation. The process was completed with an analysis of effect and plans made for addressing future focus areas. The primary area of concern identified was interservice communication. Changes centering on a standardized morning report structure reduced the number of consult questions unanswered from 67% to 34% (p = 0.0021). Physical therapy rework was reduced from 35% to 19% (p = 0.016). Patients admitted to units not designated to the trauma service had 1.6 times longer stays (p < 0.0001). The lean process lasted 8 months, and three areas for new improvement were identified: (1) the off-unit patients; (2) patients with length of stay more than 15 days contribute disproportionately to length of stay; and (3) miscommunication exists around patient education at discharge. Lean process improvement is a viable means of health care analysis. When applied to a trauma service with 4,000 admissions annually, lean identifies areas ripe for improvement. Our inefficiencies surrounded communication and patient localization. Strategies arising from the input of all stakeholders led to real solutions for communication through a face-to-face morning report and identified areas for ongoing improvement. This focuses resource use and identifies areas for improvement of throughput in care delivery.

Anthropometric and demographic predictors of handgrip strength and lean mass quality in hospitalized individuals.

PubMed

Rossato, Luana T; Barbosa, Cinthia D; Nahas, Paula C; Orsatti, Fábio L; de Oliveira, Erick P

2018-04-01

Low strength and/or lean mass quality are associated with higher hospitalization and mortality. The aim of this study was to evaluate the main demographic and anthropometric predictors of strength and lean mass quality in hospitalized patients. We evaluated 136 patients (18-86 years) of both sexes, admitted in a public hospital. Waist circumference (WC) was measured using an inelastic tape, lean mass (LM) was assessed by bioimpedance, and handgrip strength (HGS) was performed using a dynamometer. Lean mass quality (HGS/LM) was also calculated. We noted that LM predicted 33.1% of HGS, whereas WC was not associated with HGS. Evaluating LM and WC in the same statistical model, WC (β = -0.249, p = 0.001) increased the prediction of HGS by 4.7% when compared to LM alone. Accessing LM, WC, age, and sex in the same model an increase in the prediction of HGS by 7.3% was noted when compared to LM alone, but only LM and sex were significant. In addition, WC predicted the lean mass quality by 4% (β = -0.205, p = 0.016) and when WC, sex, and age were placed in the same model; WC (β = -0.172, p = 0.035) and sex (β = 0.332, p < 0.001) explained the variations in lean mass quality by 15%. The main predictor of lower HGS was lower LM, whereas sex showed a low association. Furthermore, although a low association was found, higher abdominal obesity and sex predicted lower lean mass quality. Copyright © 2018 European Society for Clinical Nutrition and Metabolism. Published by Elsevier Ltd. All rights reserved.

Diet-induced thermogenesis and substrate oxidation are not different between lean and obese women after two different isocaloric meals, one rich in protein and one rich in fat.

PubMed

Tentolouris, Nicholas; Pavlatos, Spyridon; Kokkinos, Alexander; Perrea, Despoina; Pagoni, Stamata; Katsilambros, Nicholas

2008-03-01

Reduction in diet-induced thermogenesis (DIT) may promote weight gain and maintenance. Data on differences in DIT and macronutrient oxidation between lean and obese subjects are conflicting. In this study, we sought for differences in DIT and macronutrient oxidation between lean and obese women after consumption of 2 different isocaloric meals, one rich in protein and one rich in fat. Fifteen lean and 15 obese women were studied on 2 occasions, 1 week apart. In one visit, they consumed a protein-rich meal; in the other visit, a fat-rich meal. The 2 meals were isocaloric ( approximately 2026 kJ each), of equal volume, and given in random order. Resting energy expenditure and macronutrient oxidation rates were measured and calculated in the fasting state and every 1 hour for 3 hours after meal consumption. Diet-induced thermogenesis was not significantly different between lean and obese subjects after consumption of either the protein-rich (P = .59) or the fat-rich meal (P = .68). Diet-induced thermogenesis was significantly higher (by almost 3-fold) after consumption of the protein-rich meal in comparison with the fat-rich meal in both study groups. In addition, no significant differences in macronutrient oxidation rates were found between lean and obese women after the test meals. The results indicate that DIT is higher after protein intake than after fat intake in both lean and obese participants; however, DIT and macronutrient oxidation rate are not different between lean and obese subjects after consumption of either a protein-rich or a fat-rich meal. Over the long term, a low DIT after regular or frequent fat intake may contribute to the development and maintenance of obesity.

Leptin production during early starvation in lean and obese women.

PubMed

Klein, S; Horowitz, J F; Landt, M; Goodrick, S J; Mohamed-Ali, V; Coppack, S W

2000-02-01

We evaluated abdominal adipose tissue leptin production during short-term fasting in nine lean [body mass index (BMI) 21 +/- 1 kg/m(2)] and nine upper body obese (BMI 36 +/- 1 kg/m(2)) women. Leptin kinetics were determined by arteriovenous balance across abdominal subcutaneous adipose tissue at 14 and 22 h of fasting. At 14 h of fasting, net leptin release from abdominal adipose tissue in obese subjects (10.9 +/- 1.9 ng x 100 g tissue x (-1) x min(-1)) was not significantly greater than the values observed in the lean group (7.6 +/- 2.1 ng x 100 g(-1) x min(-1)). Estimated whole body leptin production was approximately fivefold greater in obese (6.97 +/- 1.18 microg/min) than lean subjects (1.25 +/- 0.28 microg/min) (P < 0.005). At 22 h of fasting, leptin production rates decreased in both lean and obese groups (to 3.10 +/- 1.31 and 10.5 +/- 2.3 ng x 100 g adipose tissue(-1) x min(-1), respectively). However, the relative declines in both arterial leptin concentration and local leptin production in obese women (arterial concentration 13.8 +/- 4.4%, local production 10.0 +/- 12.3%) were less (P < 0.05 for both) than the relative decline in lean women (arterial concentration 39.0 +/- 5.5%, local production 56.9 +/- 13.0%). This study demonstrates that decreased leptin production accounts for the decline in plasma leptin concentration observed after fasting. However, compared with lean women, the fasting-induced decline in leptin production is blunted in women with upper body obesity. Differences in leptin production during fasting may be responsible for differences in the neuroendocrine response to fasting previously observed in lean and obese women.

Convergence in insulin resistance between very severely obese and lean women at the end of pregnancy.

PubMed

Forbes, Shareen; Barr, Sarah M; Reynolds, Rebecca M; Semple, Scott; Gray, Calum; Andrew, Ruth; Denison, Fiona C; Walker, Brian R; Norman, Jane E

2015-11-01

Disrupted intermediary metabolism may contribute to the adverse pregnancy outcomes in women with very severe obesity. Our aim was to study metabolism in such pregnancies. We recruited a longitudinal cohort of very severely obese (n = 190) and lean (n = 118) glucose-tolerant women for anthropometric and metabolic measurements at early, mid and late gestation and postpartum. In case-control studies of very severely obese and lean women we measured glucose and glycerol turnover during low- and high-dose hyperinsulinaemic-euglycaemic clamps (HEC) at early and late pregnancy and in non-pregnant women (each n = 6-9) and body fat distribution by MRI in late pregnancy (n = 10/group). Although greater glucose, insulin, NEFA and insulin resistance (HOMA-IR), and greater weight and % fat mass (FM) was observed in very severely obese vs lean participants, the degree of worsening was attenuated in the very severely obese individuals with advancing gestation, with no difference in triacylglycerol (TG) concentrations between very severely obese and lean women at term. Enhanced glycerol production was observed in early pregnancy only in very severely obese individuals, with similar intrahepatic FM in very severely obese vs lean women by late gestation. Offspring from obese mothers were heavier (p = 0.04). Pregnancies complicated by obesity demonstrate attenuation in weight gain and insulin resistance compared with pregnancies in lean women. Increased glycerol production is confined to obese women in early pregnancy and obese and lean individuals have similar intrahepatic FM by term. When targeting maternal metabolism to treat adverse pregnancy outcomes, therapeutic intervention may be most effective applied early in pregnancy.

Scaling Lean in primary care: impacts on system performance.

PubMed

Hung, Dorothy Y; Harrison, Michael I; Martinez, Meghan C; Luft, Harold S

2017-03-01

We examined a wide range of performance outcomes after Lean methodology-a leading strategy to enhance efficiency and patient value-was implemented and scaled across all primary care clinics in a nonprofit, ambulatory care delivery system. Using a stepped wedge approach, we assessed changes associated with the phased introduction of Lean-based redesigns across 46 primary care departments in 17 different clinic locations. Longitudinal analysis of operational metrics included: workflow efficiency, physician productivity, operating expenses, clinical quality, and satisfaction among patients, physicians, and staff. We used interrupted time series analysis with generalized linear mixed models to estimate Lean impacts over time. Projected outcomes in the absence of changes (ie, counterfactuals) were compared with observed outcomes after Lean redesigns were implemented, and mean differences were assessed using 95% bias-corrected bootstrap confidence intervals (CIs). We observed systemwide improvements in workflow efficiencies (eg, 95% CI, 5.8-10.4) and physician productivity (95% CI, 3.9-27.2), with no adverse effects on clinical quality. Patient satisfaction increased with respect to access to care (95% CI, 15.2-20.7), handling of personal issues (95% CI, 2.1-6.9), and overall experience of care (95% CI, 11.0-17.0), but decreased with respect to interactions with care providers (95% CI, -13.4 to -5.7). Departmental operating costs decreased, and annual staff and physician satisfaction scores increased particularly among early adopters, with key improvements in employee engagement, connection to purpose, relationships with staff, and physician time spent working. Lean redesigns can benefit primary care patients, physicians, and staff without negatively impacting the quality of clinical care. Study results may lead other delivery system leaders to innovate using Lean techniques and may further enhance support for Lean learning among public and private payers.

Is lost lean mass from intentional weight loss recovered during weight regain in postmenopausal women?

PubMed

Beavers, Kristen M; Lyles, Mary F; Davis, Cralen C; Wang, Xuewen; Beavers, Daniel P; Nicklas, Barbara J

2011-09-01

Despite the well-known recidivism of obesity, surprisingly little is known about the composition of body weight during weight regain. The objective of this study was to determine whether the composition of body weight regained after intentional weight loss is similar to the composition of body weight lost. The design was a follow-up to a randomized controlled trial of weight loss in which body composition was analyzed and compared in 78 postmenopausal women before the intervention, immediately after the intervention, and 6 and 12 mo after the intervention. All body mass and composition variables were lower immediately after weight loss than at baseline (all P < 0.05). More fat than lean mass was lost with weight loss, which resulted in body-composition changes favoring a lower percentage of body fat and a higher lean-to-fat mass ratio (P < 0.001). Considerable interindividual variability in weight regain was noted (CV = 1.07). In women who regained ≥2 kg body weight, a decreasing trend in the lean-to-fat mass ratio was observed, which indicated greater fat mass accretion than lean mass accretion (P < 0.001). Specifically, for every 1 kg fat lost during the weight-loss intervention, 0.26 kg lean tissue was lost; for every 1 kg fat regained over the following year, only 0.12 kg lean tissue was regained. Although not all postmenopausal women who intentionally lose weight will regain it within 1 y, the data suggest that fat mass is regained to a greater degree than is lean mass in those who do experience some weight regain. The health ramifications of our findings remain to be seen.

Zinc metabolism in genetically obese (ob/ob) mice

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kennedy, M.L.; Failla, M.L.

1987-05-01

Recent reports indicate that the concentrations and total amounts of several essential trace metals in various tissues of genetically obese rodents differ markedly from those in lean controls. In the present studies the absorption, retention and tissue distribution of zinc and constitutive levels of zinc-metallothionein (Zn-MT) in selected tissues were compared in obese (ob/ob) and lean (+/.) C57BL/6J mice. When 5-, 10- and 22-wk-old mice were administered 1.2 mumol /sup 65/Zn by stomach tube the apparent absorption of /sup 65/Zn by obese mice was 1.5, 2.2 and 3.9 times higher, respectively, than that in age-matched lean mice. Retention of orallymore » administered /sup 65/Zn after 96 h was also substantially higher in obese mice than in lean mice. To assess the possible influences of hyperphagia and intestinal hypertrophy on the enhanced apparent absorption of /sup 65/Zn by obese mice food intake by an additional group of obese mice was restricted to that of age-matched lean controls. When actual absorption of zinc was determined according to the method of Heth and Hoekstra, groups of ad libitum--fed obese, pair-fed obese and lean mice absorbed 38, 32 and 18% of administered /sup 65/Zn, respectively. In contrast, the rate of /sup 65/Zn excretion 2-6 d after oral or subcutaneous administration of the metal was similar for obese and lean mice. Unrestricted and pair-fed obese mice had significantly lower percentages of carcass /sup 65/Zn present in skin, muscle plus bone, spleen and testes and higher percentages present in liver, small intestine and adipose tissue than lean mice.« less

Lean muscle volume of the thigh has a stronger relationship with muscle power than muscle strength in women with knee osteoarthritis.

PubMed

Davison, Michael J; Maly, Monica R; Keir, Peter J; Hapuhennedige, Sandani M; Kron, Amie T; Adachi, Jonathan D; Beattie, Karen A

2017-01-01

Thigh lean muscle and intramuscular fat have been implicated in the impairment of physical function observed in people with knee osteoarthritis. We investigated the relationships of quadriceps and hamstrings intramuscular fat fraction and lean muscle volume with muscle power and strength, controlling for neuromuscular activation, and physical performance in women with knee OA. Women (n=20) 55years or older with symptomatic, radiographic knee osteoarthritis underwent a 3.0T magnetic resonance imaging scan of the thigh of their most symptomatic knee. Axial fat-separated images were analyzed using software to quantify intramuscular fat and lean muscle volumes of the quadriceps and hamstrings. To quantify strength and power of the knee extensors and flexors, participants performed maximum voluntary isometric contraction and isotonic knee extensions and flexions, respectively. Electromyography of the quadriceps and hamstrings was measured. Participants also completed five physical performance tests. Quadriceps and hamstrings lean muscle volumes were related to isotonic knee extensor (B=0.624; p=0.017) and flexor (B=1.518; p=0.032) power, but not knee extensor (B=0.001; p=0.615) or flexor (B=0.001; p=0.564) isometric strength. Intramuscular fat fractions were not related to isotonic knee extensor or flexor power, nor isometric strength. No relationships were found between intramuscular fat or lean muscle volume and physical performance. Muscle power may be more sensitive than strength to lean muscle mass in women with knee osteoarthritis. Thigh lean muscle mass, but neither intramuscular nor intermuscular fat, is related to knee extensor and flexor power in women with knee osteoarthritis. Copyright © 2016 Elsevier Ltd. All rights reserved.

Contributions of lean mass and fat mass to bone mineral density: a study in postmenopausal women.

PubMed

Ho-Pham, Lan T; Nguyen, Nguyen D; Lai, Thai Q; Nguyen, Tuan V

2010-03-26

The relative contribution of lean and fat to the determination of bone mineral density (BMD) in postmenopausal women is a contentious issue. The present study was undertaken to test the hypothesis that lean mass is a better determinant of BMD than fat mass. This cross-sectional study involved 210 postmenopausal women of Vietnamese background, aged between 50 and 85 years, who were randomly sampled from various districts in Ho Chi Minh City (Vietnam). Whole body scans, femoral neck, and lumbar spine BMD were measured by DXA (QDR 4500, Hologic Inc., Waltham, MA). Lean mass (LM) and fat mass (FM) were derived from the whole body scan. Furthermore, lean mass index (LMi) and fat mass index (FMi) were calculated as ratio of LM or FM to body height in metre squared (m2). In multiple linear regression analysis, both LM and FM were independent and significant predictors of BMD at the spine and femoral neck. Age, lean mass and fat mass collectively explained 33% variance of lumbar spine and 38% variance of femoral neck BMD. Replacing LM and FM by LMi and LMi did not alter the result. In both analyses, the influence of LM or LMi was greater than FM and FMi. Simulation analysis suggested that a study with 1000 individuals has a 78% chance of finding the significant effects of both LM and FM, and a 22% chance of finding LM alone significant, and zero chance of finding the effect of fat mass alone. These data suggest that both lean mass and fat mass are important determinants of BMD. For a given body size -- measured either by lean mass or height --women with greater fat mass have greater BMD.

Lean interventions in healthcare: do they actually work? A systematic literature review.

PubMed

Moraros, John; Lemstra, Mark; Nwankwo, Chijioke

2016-04-01

Lean is a widely used quality improvement methodology initially developed and used in the automotive and manufacturing industries but recently expanded to the healthcare sector. This systematic literature review seeks to independently assess the effect of Lean or Lean interventions on worker and patient satisfaction, health and process outcomes, and financial costs. We conducted a systematic literature review of Medline, PubMed, Cochrane Library, CINAHL, Web of Science, ABI/Inform, ERIC, EMBASE and SCOPUS. Peer reviewed articles were included if they examined a Lean intervention and included quantitative data. Methodological quality was assessed using validated critical appraisal checklists. Publically available data collected by the Saskatchewan Health Quality Council and the Saskatchewan Union of Nurses were also analysed and reported separately. Data on design, methods, interventions and key outcomes were extracted and collated. Our electronic search identified 22 articles that passed methodological quality review. Among the accepted studies, 4 were exclusively concerned with health outcomes, 3 included both health and process outcomes and 15 included process outcomes. Our study found that Lean interventions have: (i) no statistically significant association with patient satisfaction and health outcomes; (ii) a negative association with financial costs and worker satisfaction and (iii) potential, yet inconsistent, benefits on process outcomes like patient flow and safety. While some may strongly believe that Lean interventions lead to quality improvements in healthcare, the evidence to date simply does not support this claim. More rigorous, higher quality and better conducted scientific research is required to definitively ascertain the impact and effectiveness of Lean in healthcare settings. © The Author 2016. Published by Oxford University Press in association with the International Society for Quality in Health Care.

Lean interventions in healthcare: do they actually work? A systematic literature review

PubMed Central

Moraros, John; Lemstra, Mark; Nwankwo, Chijioke

2016-01-01

Purpose Lean is a widely used quality improvement methodology initially developed and used in the automotive and manufacturing industries but recently expanded to the healthcare sector. This systematic literature review seeks to independently assess the effect of Lean or Lean interventions on worker and patient satisfaction, health and process outcomes, and financial costs. Data sources We conducted a systematic literature review of Medline, PubMed, Cochrane Library, CINAHL, Web of Science, ABI/Inform, ERIC, EMBASE and SCOPUS. Study selection Peer reviewed articles were included if they examined a Lean intervention and included quantitative data. Methodological quality was assessed using validated critical appraisal checklists. Publically available data collected by the Saskatchewan Health Quality Council and the Saskatchewan Union of Nurses were also analysed and reported separately. Data extraction Data on design, methods, interventions and key outcomes were extracted and collated. Results of data synthesis Our electronic search identified 22 articles that passed methodological quality review. Among the accepted studies, 4 were exclusively concerned with health outcomes, 3 included both health and process outcomes and 15 included process outcomes. Our study found that Lean interventions have: (i) no statistically significant association with patient satisfaction and health outcomes; (ii) a negative association with financial costs and worker satisfaction and (iii) potential, yet inconsistent, benefits on process outcomes like patient flow and safety. Conclusion While some may strongly believe that Lean interventions lead to quality improvements in healthcare, the evidence to date simply does not support this claim. More rigorous, higher quality and better conducted scientific research is required to definitively ascertain the impact and effectiveness of Lean in healthcare settings. PMID:26811118

Theory for broadband Noise of Rotor and Stator Cascades with Inhomogeneous Inflow Turbulence Including Effects of Lean and Sweep

NASA Technical Reports Server (NTRS)

Hanson, Donald B.

2001-01-01

The problem of broadband noise generated by turbulence impinging on a downstream blade row is examined from a theoretical viewpoint. Equations are derived for sound power spectra in terms of 3 dimensional wavenumber spectra of the turbulence. Particular attention is given to issues of turbulence inhomogeneity associated with the near field of the rotor and variations through boundary layers. Lean and sweep of the rotor or stator cascade are also handled rigorously with a full derivation of the relevant geometry and definitions of lean and sweep angles. Use of the general theory is illustrated by 2 simple theoretical spectra for homogeneous turbulence. Limited comparisons are made with data from model fans designed by Pratt & Whitney, Allison, and Boeing. Parametric studies for stator noise are presented showing trends with Mach number, vane count, turbulence scale and intensity, lean, and sweep. Two conventions are presented to define lean and sweep. In the "cascade system" lean is a rotation out of its plane and sweep is a rotation of the airfoil in its plane. In the "duct system" lean is the leading edge angle viewing the fan from the front (along the fan axis) and sweep is the angle viewing the fan from the side (,perpendicular to the axis). It is shown that the governing parameter is sweep in the plane of the airfoil (which reduces the chordwise component of Mach number). Lean (out of the plane of the airfoil) has little effect. Rotor noise predictions are compared with duct turbulence/rotor interaction noise data from Boeing and variations, including blade tip sweep and turbulence axial and transverse scales are explored.

Lean mass and fat mass predict bone mineral density in middle-aged individuals with noninsulin-requiring type 2 diabetes mellitus.

PubMed

Moseley, Kendall F; Dobrosielski, Devon A; Stewart, Kerry J; De Beur, Suzanne M Jan; Sellmeyer, Deborah E

2011-05-01

Despite high bone mineral density (BMD), persons with type 2 diabetes are at greater risk of fracture. The relationship between body composition and BMD in noninsulin-requiring diabetes is unclear. The aim was to examine how fat and lean mass independently affect the skeleton in this population. Subjects for this cross-sectional analysis were men (n = 78) and women (n = 56) aged 40-65 years (56 ± 6 years) with uncomplicated, noninsulin-requiring type 2 diabetes. Total body fat and lean mass, total body, hip and lumbar spine BMD were measured with dual energy X-ray absorptiometry. Magnetic resonance imaging measured total abdominal, visceral and subcutaneous (SQ) fat. Subjects had normal all-site BMD and were obese to overweight (body mass index 29-41 kg/m(2)) with controlled diabetes (HbA1c women 6·6 ± 1·2%, men 6·7 ± 1·6%). Lean mass was positively associated with total body, hip, femoral neck and hip BMD in both sexes. Fat mass, abdominal total and SQ fat were associated with total body and hip BMD in women. In multivariate analyses adjusted for sex, lean mass significantly predicted total, hip and femoral neck BMD in men and women. In unadjusted models, lean mass continued to predict BMD at these sites in men; fat mass also predicted total body, femoral and hip BMD in women. In men and women with uncomplicated, noninsulin-requiring diabetes, lean mass significantly predicted BMD at the total body, hip and femoral neck. Further research is needed to determine whether acquisition or maintenance of lean mass in T2DM can prevent hip fracture in this at-risk population. © 2011 Blackwell Publishing Ltd.

Survey of the occurrence of desiccation-induced quenching of basal fluorescence in 28 species of green microalgae.

PubMed

Wieners, Paul Christian; Mudimu, Opayi; Bilger, Wolfgang

2018-05-30

Desiccation-induced chlorophyll fluorescence quenching seems to be an indispensable part of desiccation resistance in the surveyed 28 green microalgal species. Lichens are desiccation tolerant meta-organisms. In the desiccated state photosynthesis is inhibited rendering the photobionts potentially sensitive to photoinhibition. As a photoprotective mechanism, strong non-radiative dissipation of absorbed light leading to quenching of chlorophyll fluorescence has been proposed. Desiccation-induced quenching affects not only variable fluorescence, but also the so-called basal fluorescence, F 0 . This phenomenon is well-known for intact lichens and some free living aero-terrestrial algae, but it was often absent in isolated lichen algae. Therefore, a thorough screening for the appearance of desiccation-induced quenching was undertaken with 13 different aero-terrestrial microalgal species and lichen photobionts. They were compared with 15 aquatic green microalgal species, among them also three marine species. We asked the following questions: Do isolated lichen algae show desiccation-induced quenching? Are aero-terrestrial algae different in this respect to aquatic algae and is the potential for desiccation-induced quenching coupled to desiccation tolerance? How variable is desiccation-induced quenching among species? Most of the aero-terrestrial algae, including all lichen photobionts, showed desiccation-induced quenching, although highly variable in extent, whereas most of the aquatic algae did not. All algae displaying quenching were also desiccation tolerant, whereas all algae unable to perform desiccation-induced quenching were desiccation intolerant. Desiccation-induced fluorescence quenching seems to be an indispensable part of desiccation resistance in the investigated species.

From Toyota to the bedside: nurses can lead the lean way in health care reform.

PubMed

Johnson, Joyce E; Smith, Amy L; Mastro, Kari A

2012-01-01

The advent of health care reform means new pressures on American hospitals, which will be forced to do more with less. In the next decade, increased use of "Lean" principles and practices in hospitals can create real value by reducing waste and improving productivity, costs, quality, and the timely delivery of patient care services. In 2010, the Institute of Medicine recommended that nurses lead collaborative quality improvement efforts and assume a major role in redesigning health care in the United States. In this article, we provide an overview of the use of Lean techniques in health care and 2 case studies of successful, nurse-directed Lean initiatives at the Robert Wood Johnson University Hospital. The article concludes with some lessons we have learned and implications for nursing education in the future that must include the concepts, tools, and skills required for adapting Lean to the patient care environment.

Intelligent Engine Systems: Alternate Fuels Evaluation

NASA Technical Reports Server (NTRS)

Ballal, Dilip

2008-01-01

The performance and gaseous emissions were measured for a well-stirred reactor operating under lean conditions for two fuels: JP8 and a synthetic Fisher-Tropsch fuel over a range of equivalence ratios from 0.6 down to the lean blowout. The lean blowout characteristics were determined in LBO experiments at loading parameter values from 0.7 to 1.4. The lean blowout characteristics were then explored under higher loading conditions by simulating higher altitude operation with the use of nitrogen as a dilution gas for the air stream. The experiments showed that: (1) The lean blowout characteristics for the two fuels were close under both low loading and high loading conditions. (2) The combustion temperatures and observed combustion efficiencies were similar for the two fuels. (3) The gaseous emissions were similar for the two fuels and the differences in the H2O and CO2 emissions appear to be directly relatable to the C/H ratio for the fuels.

Lean mixture engine testing and evaluation program. [for automobile engine pollution and fuel performances

NASA Technical Reports Server (NTRS)

Dowdy, M. W.; Hoehn, F. W.; Griffin, D. C.

1975-01-01

Experimental results for fuel consumption and emissions are presented for a 350 CID (5.7 liter) Chevrolet V-8 engine modified for lean operation with gasoline. The lean burn engine achieved peak thermal efficiency at an equivalence ratio of 0.75 and a spark advance of 60 deg BTDC. At this condition the lean burn engine demonstrated a 10% reduction in brake specific fuel consumption compared with the stock engine; however, NOx and hydrocarbon emissions were higher. With the use of spark retard and/or slightly lower equivalence ratios, the NOx emissions performance of the stock engine was matched while showing a 6% reduction in brake specific fuel consumption. Hydrocarbon emissions exceeded the stock values in all cases. Diagnostic data indicate that lean performance in the engine configuration tested is limited by ignition delay, cycle-to-cycle pressure variations, and cylinder-to-cylinder distribution.

System and method for treatment of a flue gas

DOE Office of Scientific and Technical Information (OSTI.GOV)

Spiry, Irina Pavlovna; Wood, Benjamin Rue; Singh, Surinder Prabhjot

A method for treatment of a flue gas involves feeding the flue gas and a lean solvent to an absorber. The method further involves reacting the flue gas with the lean solvent within the absorber to generate a clean flue gas and a rich solvent. The method also involves feeding the clean flue gas from the absorber and water from a source, to a wash tower to separate a stripped portion of the lean solvent from the clean flue gas to generate a washed clean flue gas and a mixture of the water and the stripped portion of the leanmore » solvent. The method further involves treating at least a portion of the mixture of the water and the stripped portion of the lean solvent via a separation system to separate the water from the stripped portion of the lean solvent.« less

The effect of a Lean quality improvement implementation program on surgical pathology specimen accessioning and gross preparation error frequency.

PubMed

Smith, Maxwell L; Wilkerson, Trent; Grzybicki, Dana M; Raab, Stephen S

2012-09-01

Few reports have documented the effectiveness of Lean quality improvement in changing anatomic pathology patient safety. We used Lean methods of education; hoshin kanri goal setting and culture change; kaizen events; observation of work activities, hand-offs, and pathways; A3-problem solving, metric development, and measurement; and frontline work redesign in the accessioning and gross examination areas of an anatomic pathology laboratory. We compared the pre- and post-Lean implementation proportion of near-miss events and changes made in specific work processes. In the implementation phase, we documented 29 individual A3-root cause analyses. The pre- and postimplementation proportions of process- and operator-dependent near-miss events were 5.5 and 1.8 (P < .002) and 0.6 and 0.6, respectively. We conclude that through culture change and implementation of specific work process changes, Lean implementation may improve pathology patient safety.

Lean thinking across a hospital: redesigning care at the Flinders Medical Centre.

PubMed

Ben-Tovim, David I; Bassham, Jane E; Bolch, Denise; Martin, Margaret A; Dougherty, Melissa; Szwarcbord, Michael

2007-02-01

Lean thinking is a method for organising complex production processes so as to encourage flow and reduce waste. While the principles of lean thinking were developed in the manufacturing sector, there is increasing interest in its application in health care. This case history documents the introduction and development of Redesigning Care, a lean thinking-based program to redesign care processes across a teaching general hospital. Redesigning Care has produced substantial benefits over the first two-and-a-half years of its implementation, making care both safer and more accessible. Redesigning Care has not been aimed at changing the specifics of clinical practice. Rather, it has been concerned with improving the flow of patients through clinical and other systems. Concepts that emerged in the manufacturing sector have been readily translatable into health care. Lean thinking may play an important role in the reform of health care in Australia and elsewhere.

System and method for quench protection of a superconductor

DOEpatents

Huang, Xianrui; Sivasubramaniam, Kiruba Haran; Bray, James William; Ryan, David Thomas

2008-03-11

A system and method for protecting a superconductor from a quench condition. A quench protection system is provided to protect the superconductor from damage due to a quench condition. The quench protection system comprises a voltage detector operable to detect voltage across the superconductor. The system also comprises a frequency filter coupled to the voltage detector. The frequency filter is operable to couple voltage signals to a control circuit that are representative of a rise in superconductor voltage caused by a quench condition and to block voltage signals that are not. The system is operable to detect whether a quench condition exists in the superconductor based on the voltage signal received via the frequency filter and to initiate a protective action in response.

Quench dynamics in MgB2 Rutherford cables

NASA Astrophysics Data System (ADS)

Cubero, A.; Navarro, R.; Kováč, P.; Kopera, L.; Rindfleisch, M.; Martínez, E.

2018-04-01

The generation and propagation of quench induced by a local heat disturbance or by overcurrents in MgB2 Rutherford cables have been studied experimentally. The analysed cable is composed of 12 strands of monocore MgB2/Nb/Cu10Ni wire and has a transposition length of about 27 mm. Measurements of intra- and inter-strand voltages have been performed to analyse the superconducting-to-normal transition behaviour of these cables during quench. In case of external hot-spots, two different time-dynamic regimes have been observed, a slow stage for the formation of the minimum propagation zone (MPZ), and a fast dynamics once the quench is triggered and propagates to the rest of the cable. Significant local variations of the quench propagation velocity across the strands around the MPZ have been observed, but with average quench propagation velocities closely correlated with the predictions given by one-dimensional-geometry models. For quench induced by overcurrents (i.e. with applied currents higher than the critical current) the nucleation of many normal zones distributed within the cable, which overlap during quench propagation, gives a distinctive and faster quench dynamics.

Investigation of common fluorophores for the detection of nitrated explosives by fluorescence quenching.

PubMed

Meaney, Melissa S; McGuffin, Victoria L

2008-03-03

Previous studies have indicated that nitrated explosives may be detected by fluorescence quenching of pyrene and related compounds. The use of pyrene, however, invokes numerous health and waste disposal hazards. In the present study, ten safer fluorophores are identified for quenching detection of target nitrated compounds. Initially, Stern-Volmer constants are measured for each fluorophore with nitrobenzene and 4-nitrotoluene to determine the sensitivity of the quenching interaction. For quenching constants greater than 50 M(-1), sensitivity and selectivity are investigated further using an extended set of target quenchers. Nitromethane, nitrobenzene, 4-nitrotoluene, and 2,6-dinitrotoluene are chosen to represent nitrated explosives and their degradation products; aniline, benzoic acid, and phenol are chosen to represent potential interfering compounds. Among the fluorophores investigated, purpurin, malachite green, and phenol red demonstrate the greatest sensitivity and selectivity for nitrated compounds. Correlation of the quenching rate constants for these fluorophores to Rehm-Weller theory suggests an electron-transfer quenching mechanism. As a result of the large quenching constants, purpurin, malachite green, and phenol red are the most promising for future detection of nitrated explosives via fluorescence quenching.

Conversion of invisible metal-organic frameworks to luminescent perovskite nanocrystals for confidential information encryption and decryption.

PubMed

Zhang, Congyang; Wang, Bo; Li, Wanbin; Huang, Shouqiang; Kong, Long; Li, Zhichun; Li, Liang

2017-10-31

Traditional smart fluorescent materials, which have been attracting increasing interest for security protection, are usually visible under either ambient or UV light, making them adverse to the potential application of confidential information protection. Herein, we report an approach to realize confidential information protection and storage based on the conversion of lead-based metal-organic frameworks (MOFs) to luminescent perovskite nanocrystals (NCs). Owing to the invisible and controlled printable characteristics of lead-based MOFs, confidential information can be recorded and encrypted by MOF patterns, which cannot be read through common decryption methods. Through our conversion strategy, highly luminescent perovskite NCs can be formed quickly and simply by using a halide salt trigger that reacts with the MOF, thus promoting effective information decryption. Finally, through polar solvents impregnation and halide salt conversion, the luminescence of the perovskite NCs can be quenched and recovered, leading to reversible on/off switching of the luminescence signal for multiple information encryption and decryption processes.

Electrochemiluminescence sensors for scavengers of hydroxyl radical based on its annihilation in CdSe quantum dots film/peroxide system.

PubMed

Jiang, Hui; Ju, Huangxian

2007-09-01

This work elucidated the detailed electrochemiluminescence (ECL) process of the thioglycolic acid-capped CdSe quantum dots (QDs) film/peroxide aqueous system. The QDs were first electrochemically reduced to form electrons-injected QDs approximately -1.1 V, which then reduced hydrogen peroxide to produce OH* radical. The intermediate OH* radical was a key species for producing holes-injected QDs. The ECL emission with a peak at -1.114 V was demonstrated to come from the 1Se-1Sh transition emission. Using thiol compounds as the model molecules to annihilate the OH* radical, their quenching effects on ECL emission were studied. This effect led to a novel strategy for ECL sensing of the scavengers of hydroxyl radical. The detection results of thiol compounds showed high sensitivity, good precision, and acceptable accuracy, suggesting the promising application of the proposed method for quick detection of both scavengers and generators of hydroxyl radical in different fields.

A Multi-responsive Regenerable Europium-Organic Framework Luminescent Sensor for Fe3+ , CrVI Anions, and Picric Acid.

PubMed

Liu, Wei; Huang, Xin; Xu, Cong; Chen, Chunyang; Yang, Lizi; Dou, Wei; Chen, Wanmin; Yang, Huan; Liu, Weisheng

2016-12-23

A novel luminescent microporous lanthanide metal-organic framework (Ln-MOF) based on a urea-containing ligand has been successfully assembled. Structural analysis revealed that the framework features two types of 1D channels, with urea N-H bonds projecting into the pores. Luminescence studies have revealed that the Ln-MOF exhibits high sensitivity, good selectivity, and a fast luminescence quenching response towards Fe 3+ , Cr VI anions, and picric acid. In particular, in the detection of Cr 2 O 7 2- and picric acid, the Ln-MOF can be simply and quickly regenerated, thus exhibiting excellent recyclability. To the best of our knowledge, this is the first example of a multi-responsive luminescent Ln-MOF sensor for Fe 3+ , Cr VI anions, and picric acid based on a urea derivative. This Ln-MOF may potentially be used as a multi-responsive regenerable luminescent sensor for the quantitative detection of toxic and harmful substances. © 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Dissolved oxygen sensing using organometallic dyes deposited within a microfluidic environment

NASA Astrophysics Data System (ADS)

Chen, Q. L.; Ho, H. P.; Jin, L.; Chu, B. W.-K.; Li, M. J.; Yam, V. W.-W.

2008-02-01

This work primarily aims to integrate dissolved oxygen sensing capability with a microfluidic platform containing arrays of micro bio-reactors or bio-activity indicators. The measurement of oxygen concentration is of significance for a variety of bio-related applications such as cell culture and gene expression. Optical oxygen sensors based on luminescence quenching are gaining much interest in light of their low power consumption, quick response and high analyte sensitivity in comparison to similar oxygen sensing devices. In our microfluidic oxygen sensor device, a thin layer of oxygen-sensitive luminescent organometallic dye is covalently bonded to a glass slide. Micro flow channels are formed on the glass slide using patterned PDMS (Polydimethylsiloxane). Dissolved oxygen sensing is then performed by directing an optical excitation probe beam to the area of interest within the microfluidic channel. The covalent bonding approach for sensor layer formation offers many distinct advantages over the physical entrapment method including minimizing dye leaching, ensuring good stability and fabrication simplicity. Experimental results confirm the feasibility of the device.

Quench Protection Studies of 11T Nb$$_3$$Sn Dipole Models for LHC Upgrades

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zlobin, Alexander; Chlachidze, Guram; Nobrega, Alfred

CERN and FNAL are developing 11 T Nb3Sn dipole magnets for the LHC collimation system upgrade. Due to the large stored energy, protection of these magnets during a quench is a challenging problem. This paper reports the results of experimental studies of key quench protection parameters including longitudinal and radial quench propagation in the coil, coil heating due to a quench, and energy extraction and quench-back effect. The studies were performed using a 1 m long 11 T Nb3Sn dipole coil tested in a magnetic mirror configuration.

Quench simulations for superconducting elements in the LHC accelerator

NASA Astrophysics Data System (ADS)

Sonnemann, F.; Schmidt, R.

2000-08-01

The design of the protection system for the superconducting elements in an accelerator such as the large Hadron collider (LHC), now under construction at CERN, requires a detailed understanding of the thermo-hydraulic and electrodynamic processes during a quench. A numerical program (SPQR - simulation program for quench research) has been developed to evaluate temperature and voltage distributions during a quench as a function of space and time. The quench process is simulated by approximating the heat balance equation with the finite difference method in presence of variable cooling and powering conditions. The simulation predicts quench propagation along a superconducting cable, forced quenching with heaters, impact of eddy currents induced by a magnetic field change, and heat transfer through an insulation layer into helium, an adjacent conductor or other material. The simulation studies allowed a better understanding of experimental quench data and were used for determining the adequate dimensioning and protection of the highly stabilised superconducting cables for connecting magnets (busbars), optimising the quench heater strip layout for the main magnets, and studying quench back by induced eddy currents in the superconductor. After the introduction of the theoretical approach, some applications of the simulation model for the LHC dipole and corrector magnets are presented and the outcome of the studies is compared with experimental data.

Adipose energy stores, physical work, and the metabolic syndrome: lessons from hummingbirds

PubMed Central

Hargrove, James L

2005-01-01

Hummingbirds and other nectar-feeding, migratory birds possess unusual adaptive traits that offer important lessons concerning obesity, diabetes and the metabolic syndrome. Hummingbirds consume a high sugar diet and have fasting glucose levels that would be severely hyperglycemic in humans, yet these nectar-fed birds recover most glucose that is filtered into the urine. Hummingbirds accumulate over 40% body fat shortly before migrations in the spring and autumn. Despite hyperglycemia and seasonally elevated body fat, the birds are not known to become diabetic in the sense of developing polyuria (glucosuria), polydipsia and polyphagia. The tiny (3–4 g) Ruby-throated hummingbird has among the highest mass-specific metabolic rates known, and loses most of its stored fat in 20 h by flying up to 600 miles across the Gulf of Mexico. During the breeding season, it becomes lean and maintains an extremely accurate energy balance. In addition, hummingbirds can quickly enter torpor and reduce resting metabolic rates by 10-fold. Thus, hummingbirds are wonderful examples of the adaptive nature of fat tissue, and may offer lessons concerning prevention of metabolic syndrome in humans. PMID:16351726

Future Software Sizing Metrics and Estimation Challenges

DTIC Science & Technology

2011-07-01

systems 4. Ultrahigh software system assurance 5. Legacy maintenance and Brownfield development 6. Agile and Lean/ Kanban development. This paper...refined as the design of the maintenance modifications or Brownfield re-engineering is determined. VII. 6. AGILE AND LEAN/ KANBAN DEVELOPMENT The...difficulties of software maintenance estimation can often be mitigated by using lean workflow management techniques such as Kanban [25]. In Kanban

An Exploration of Healthcare Inventory and Lean Management in Minimizing Medical Supply Waste in Healthcare Organizations

ERIC Educational Resources Information Center

Hicks, Rodney

2013-01-01

The purpose of this study was to understand how lean thinking and inventory management technology minimize expired medical supply waste in healthcare organizations. This study was guided by Toyota's theory of lean and Mintzberg's theory of management development to explain why the problem of medical supply waste exists. Government…

Lean premixed/prevaporized combustion

NASA Technical Reports Server (NTRS)

Lefebvre, A. H. (Editor)

1977-01-01

Recommendations were formulated on the status and application of lean premixed/prevaporized combustion to the aircraft gas turbine for the reduction of pollutant emissions. The approach taken by the NASA Stratospheric Cruise Emission Reduction Program (SCERP) in pursuing the lean premixed/prevaporized combustion technique was also discussed. The proceedings contains an overview of the SCERP program, the discussions and recommendations of the participants, and an overall summary.

Leading Lean: a Canadian healthcare leader's guide.

PubMed

Fine, Benjamin A; Golden, Brian; Hannam, Rosemary; Morra, Dante

2009-01-01

Canadian healthcare organizations are increasingly asked to do more with less, and too often this has resulted in demands on staff to simply work harder and longer. Lean methodologies, originating from Japanese industrial organizations and most notably Toyota, offer an alternative - tried and tested approaches to working smarter. Lean, with its systematic approaches to reducing waste, has found its way to Canadian healthcare organizations with promising results. This article reports on a study of five Canadian healthcare providers that have recently implemented Lean. We offer stories of success but also identify potential obstacles and ways by which they may be surmounted to provide better value for our healthcare investments.

Developing weighted criteria to evaluate lean reverse logistics through analytical network process

NASA Astrophysics Data System (ADS)

Zagloel, Teuku Yuri M.; Hakim, Inaki Maulida; Krisnawardhani, Rike Adyartie

2017-11-01

Reverse logistics is a part of supply chain that bring materials from consumers back to manufacturer in order to gain added value or do a proper disposal. Nowadays, most companies are still facing several problems on reverse logistics implementation which leads to high waste along reverse logistics processes. In order to overcome this problem, Madsen [Framework for Reverse Lean Logistics to Enable Green Manufacturing, Eco Design 2009: 6th International Symposium on Environmentally Conscious Design and Inverse Manufacturing, Sapporo, 2009] has developed a lean reverse logistics framework as a step to eliminate waste by implementing lean on reverse logistics. However, the resulted framework sets aside criteria used to evaluate its performance. This research aims to determine weighted criteria that can be used as a base on reverse logistics evaluation by considering lean principles. The resulted criteria will ensure reverse logistics are kept off from waste, thus implemented efficiently. Analytical Network Process (ANP) is used in this research to determine the weighted criteria. The result shows that criteria used for evaluation lean reverse logistics are Innovation and Learning (35%), Economic (30%), Process Flow Management (14%), Customer Relationship Management (13%), Environment (6%), and Social (2%).

Development of an interprofessional lean facilitator assessment scale.

PubMed

Bravo-Sanchez, Cindy; Dorazio, Vincent; Denmark, Robert; Heuer, Albert J; Parrott, J Scott

2018-05-01

High reliability is important for optimising quality and safety in healthcare organisations. Reliability efforts include interprofessional collaborative practice (IPCP) and Lean quality/process improvement strategies, which require skilful facilitation. Currently, no validated Lean facilitator assessment tool for interprofessional collaboration exists. This article describes the development and pilot evaluation of such a tool; the Interprofessional Lean Facilitator Assessment Scale (ILFAS), which measures both technical and 'soft' skills, which have not been measured in other instruments. The ILFAS was developed using methodologies and principles from Lean/Shingo, IPCP, metacognition research and Bloom's Taxonomy of Learning Domains. A panel of experts confirmed the initial face validity of the instrument. Researchers independently assessed five facilitators, during six Lean sessions. Analysis included quantitative evaluation of rater agreement. Overall inter-rater agreement of the assessment of facilitator performance was high (92%), and discrepancies in the agreement statistics were analysed. Face and content validity were further established, and usability was evaluated, through primary stakeholder post-pilot feedback, uncovering minor concerns, leading to tool revision. The ILFAS appears comprehensive in the assessment of facilitator knowledge, skills, abilities, and may be useful in the discrimination between facilitators of different skill levels. Further study is needed to explore instrument performance and validity.

Effect of low appendicular lean mass, grip strength, and gait speed on the functional outcome after surgery for distal radius fractures.

PubMed

Roh, Young Hak; Noh, Jung Ho; Gong, Hyun Sik; Baek, Goo Hyun

2017-12-01

Patients with low appendicular lean mass plus slow gait speed or weak grip strength are at risk for poor functional recovery after surgery for distal radius fracture, even when they have similar radiologic outcomes. Loss of skeletal muscle mass and consequent loss in muscle function associate with aging, and this condition negatively impacts the activities of daily living and increases elderly individuals' frailty to falls. Thus, patients with low appendicular lean mass would show different functional recovery compared to those without this condition after surgery for distal radius fracture (DRF). This study compares the functional outcomes after surgery for DRF in patients with or without low appendicular lean mass plus slowness or weakness. A total of 157 patients older than 50 years of age with a DRF treated via volar plate fixation were enrolled in this prospective study. A definition of low appendicular lean mass with slowness or weakness was based on the consensus of the Asian Working Group for Sarcopenia. The researchers compared functional assessments (wrist range of motion and Michigan Hand Questionnaire [MHQ]) and radiographic assessments (radial inclination, volar tilt, ulnar variance, and articular congruity) 12 months after surgery between patients with and without low appendicular lean mass plus slowness or weakness. Multivariable regression analyses were performed to determine whether appendicular lean mass, grip strength, gait speed, patient demographic, or injury characteristics accounted for the functional outcomes. Patients with low appendicular lean mass plus slowness or weakness showed a significantly lower recovery of MHQ score than those in the control group throughout 12 months. There was no significant difference in the range of motion between the groups. The radiologic outcomes showed no significant difference between groups in terms of volar tilt, radial inclination, or ulnar variance. According to multivariable regression analysis, the poor recovery of MHQ score was associated with an increase in age, weak grip strength, and lower appendicular lean mass, and these three factors accounted for 37% of the variation in the MHQ scores. Patients with low appendicular lean mass plus slowness or weakness are at risk for poor functional recovery after surgery for DRF, even when they have similar radiologic outcomes.

Exaggerated haemodynamic and neural responses to involuntary contractions induced by whole-body vibration in normotensive obese versus lean women.

PubMed

Dipla, Konstantina; Kousoula, Dimitra; Zafeiridis, Andreas; Karatrantou, Konstantina; Nikolaidis, Michalis G; Kyparos, Antonios; Gerodimos, Vassilis; Vrabas, Ioannis S

2016-06-01

What is the central question of this study? In obesity, the exaggerated blood pressure response to voluntary exercise is linked to hypertension, yet the mechanisms are not fully elucidated. We examined whether involuntary contractions elicit greater haemodynamic responses and altered neural control of blood pressure in normotensive obese versus lean women. What is the main finding and its importance? During involuntary contractions induced by whole-body vibration, there were augmented blood pressure and spontaneous baroreflex responses in obese compared with lean women. This finding is suggestive of an overactive mechanoreflex in the exercise-induced hypertensive response in obesity. Passive contractions did not elicit differential heart rate responses in obese compared with lean women, implying other mechanisms for the blunted heart rate response reported during voluntary exercise in obesity. In obesity, the exaggerated blood pressure (BP) response to exercise is linked to hypertension, yet the mechanisms are not fully elucidated. In this study, we examined whether involuntary mechanical oscillations, induced by whole-body vibration (WBV), elicit greater haemodynamic responses and altered neural control of BP in obese versus lean women. Twenty-two normotensive, premenopausal women (12 lean and 10 obese) randomly underwent a passive WBV (25 Hz) and a control protocol (similar posture without WVB). Beat-by-beat BP, heart rate, stroke volume, systemic vascular resistance, cardiac output, parasympathetic output (evaluated by heart rate variability) and spontaneous baroreceptor sensitivity (sBRS) were assessed. We found that during WBV, obese women exhibited an augmented systolic BP response compared with lean women that was correlated with body fat percentage (r = 0.77; P < 0.05). The exaggerated BP rise was driven mainly by the greater increase in cardiac output index in obese versus lean women, associated with a greater stroke volume index in obese women. Involuntary contractions did not elicit a differential magnitude of responses in heart rate, heart rate variability indices and systemic vascular resistance in obese versus lean women; however, they did result in greater sBRS responses (P < 0.05) in obese women. In conclusion, involuntary contractions elicited an augmented BP and sBRS response in normotensive obese versus lean women. The greater elevations in circulatory haemodynamics in obese women are suggestive of an overactive mechanoreflex in the exercise-induced hypertensive response in obesity. © 2016 The Authors. Experimental Physiology © 2016 The Physiological Society.

Postprandial response of ghrelin and PYY and indices of low-grade chronic inflammation in lean young women with polycystic ovary syndrome.

PubMed

Zwirska-Korczala, K; Sodowski, K; Konturek, S J; Kuka, D; Kukla, M; Brzozowski, T; Cnota, W; Woźniak-Grygiel, E; Jaworek, J; Bułdak, R; Rybus-Kalinowska, B; Fryczowski, M

2008-08-01

The aim of the study were to answer the question 1.) Whether circulating pro-inflammatory markers of endothelial dysfunction and due to chronic low-grade inflammation of obesity, are altered in untreated lean, young relatively healthy polycystic ovary syndrome (PCOS) patients in comparison with healthy controls; 2.) Whether postprandial plasma concentration pattern of ghrelin and PYY can be predictable as risk factors for atherosclerosis and depend of obesity. Forty young women with PCOS were divided in two groups: 19 lean and 21 obese. The control group included 20 lean, healthy volunteers. Plasma total and active ghrelin, total PYY and PYY(3-36), serum adiponectin and insulin were measured using RIA technique, serum sCD40L, visfatin, sP-, sE-selectins, resistin by EIA. Composition of test meal was: 527 kcal total and consisted of 24.1% fat, 54.4% carbohydrate and 21.5% protein. Total and active ghrelin and total PYY were significantly lower in obese PCOS women, whereas active ghrelin was also significantly lower in lean PCOS women compared to controls. Postprandial plasma total ghrelin levels decrease were blunted in lean and obese compared to controls (12.8 % and 18.2% vs 28.2 %). Postprandial plasma active ghrelin decreased in lean and obese PCOS groups (49.9 % and 44.1 %) and controls (63.8 %). PCOS subjects exhibited smaller rises in postprandial levels of total PYY. Postprandial plasma PYY(3-36) levels increased in obese PCOS women (30.9 %) and controls (41%), whereas lean PCOS women exhibited blunted increase (11.5%). sCD40L levels increased, whereas adiponectin decreased in PCOS groups independently, whereas rise in visfatin, sE- and sP-selectin and the fall in adiponectin was associated with obesity. sP- and sE -selectins correlated positively with obesity. In summary, our study provides the first evidence that lean untreated young PCOS women contribute to the so called "pancreatic islet adaptation to insulin resistance" because of ghrelin and PYY profiles. We confirmed existing of low-grade chronic inflammation in early stage of visceral obesity in lean PCOS patients. The lost endogenous "islet adaptation to insulin resistance" may lead to endothelial dysfunction and promote acceleration of atherosclerosis.

[Interference for Various Quench Agents of Chemical Disinfectants on Detection of Endotoxin Activities in Water].

PubMed

Zhang, Can; Liu, Wen-jun; Shi, Yun; An, Dai-zhi; Bai, Miao; Xu, Wen

2015-05-01

The quenching agents such as histidine, glycine, ascorbic acid, Tween-80, sodium sulfite and sodium hyposulfite are commonly used for quenching the residual disinfectant in water. In this paper, in order to select the optimal type and concentration range of quenching agents prior to the Limulus assays, the interference effects of each quenching agent at different concentrations on endotoxin detection were investigated by the Limulus assays of kinetic-turbidity. Our results identified that, as for 0-1.0% concentration of histidine, ascorbic acid, Tween-80, sodium sulfite (pH unadjusted and pH neutral), interference on the Limulus assays was existed. Hence, these quenching agents could not be applied as neutralizers prior to Limulus assays. Although, there was no interference on endotoxin detection for the glycine, a yellow color, developed by the quenching products of glycine and glutaric dialdehyde, contributed to false positive results. Hence, glycine should not be used as quenching agents in Limulus assays for samples containing glutaric dialdehyde. Compared with other quenching agents as histidine, glycine, ascorbic acid, Tween-80, sodium sulfite, 0-1.0% concentration of sodium hyposulfite elicited no obvious interference, while 1.0%-5.0% concentration of sodium hyposulfite illustrated exhibition effect for endotoxin detection. All in all, compared with other quenching agents as histidine, glycine, ascorbic acid, Tween-80 and sodium sulfite, sodium hyposulfite is suitable for quenching chemicals prior to endotoxin detection and less than 0.5% of concentration is allowable.

QUENCH: A software package for the determination of quenching curves in Liquid Scintillation counting.

PubMed

Cassette, Philippe

2016-03-01

In Liquid Scintillation Counting (LSC), the scintillating source is part of the measurement system and its detection efficiency varies with the scintillator used, the vial and the volume and the chemistry of the sample. The detection efficiency is generally determined using a quenching curve, describing, for a specific radionuclide, the relationship between a quenching index given by the counter and the detection efficiency. A quenched set of LS standard sources are prepared by adding a quenching agent and the quenching index and detection efficiency are determined for each source. Then a simple formula is fitted to the experimental points to define the quenching curve function. The paper describes a software package specifically devoted to the determination of quenching curves with uncertainties. The experimental measurements are described by their quenching index and detection efficiency with uncertainties on both quantities. Random Gaussian fluctuations of these experimental measurements are sampled and a polynomial or logarithmic function is fitted on each fluctuation by χ(2) minimization. This Monte Carlo procedure is repeated many times and eventually the arithmetic mean and the experimental standard deviation of each parameter are calculated, together with the covariances between these parameters. Using these parameters, the detection efficiency, corresponding to an arbitrary quenching index within the measured range, can be calculated. The associated uncertainty is calculated with the law of propagation of variances, including the covariance terms. Copyright © 2015 Elsevier Ltd. All rights reserved.