WorldWideScience

Sample records for cell cost minimization

  1. Cost minimization and asset pricing

    OpenAIRE

    Chambers, Robert G.; John Quiggin

    2005-01-01

    A cost-based approach to asset-pricing equilibrium relationships is developed. A cost function induces a stochastic discount factor (pricing kernel) that is a function of random output, prices, and capital stockt. By eliminating opportunities for arbitrage between financial markets and the production technology, firms minimize the current cost of future consumption. The first-order conditions for this cost minimization problem generate the stochastic discount factor. The cost-based approach i...

  2. PEM fuel cell cost minimization using ``Design For Manufacture and Assembly`` techniques

    Energy Technology Data Exchange (ETDEWEB)

    Lomax, F.D. Jr.; James, B.D. [Directed Technologies, Inc., Arlington, VA (United States); Mooradian, R.P. [Ford Motor Co., Dearborn, MI (United States)

    1997-12-31

    Polymer Electrolyte Membrane (PEM) fuel cells fueled with direct hydrogen have demonstrated substantial technical potential to replace Internal Combustion Engines (ICE`s) in light duty vehicles. Such a transition to a hydrogen economy offers the potential of substantial benefits from reduced criteria and greenhouse emissions as well as reduced foreign fuel dependence. Research conducted for the Ford Motor Co. under a US Department of Energy contract suggests that hydrogen fuel, when used in a fuel cell vehicle (FCV), can achieve a cost per vehicle mile less than or equal to the gasoline cost per mile when used in an ICE vehicle. However, fuel cost parity is not sufficient to ensure overall economic success: the PEM fuel cell power system itself must be of comparable cost to the ICE. To ascertain if low cost production of PEM fuel cells is feasible, a powerful set of mechanical engineering tools collectively referred to as Design for Manufacture and Assembly (DFMA) has been applied to several representative PEM fuel cell designs. The preliminary results of this work are encouraging, as presented.

  3. On Time with Minimal Expected Cost!

    DEFF Research Database (Denmark)

    David, Alexandre; Jensen, Peter Gjøl; Larsen, Kim Guldstrand;

    2014-01-01

    ) timed game essentially defines an infinite-state Markov (reward) decision proces. In this setting the objective is classically to find a strategy that will minimize the expected reachability cost, but with no guarantees on worst-case behaviour. In this paper, we provide efficient methods for computing...

  4. HEAVY OIL UPGRADING WITH MINIMAL INVESTMENT COST

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    By making best use of the low value by-products and maximum utilization of the existed processing units to minimize the investment cost,several heavy oil upgrading processes have been developed and put into practice in China.For domestic sweet crudes,RFCC combined with decanted oil coking or deasphalting has been selected.By RFCC-coking or deasphalting synergy,inferior quality feedstock can be accepted and needle coke and paving asphalt are produced.For imported sulfur crudes,high vacuum distillation combined with asphalt production and combined coking with the use of coke in cement industry and Fluidized Bed Combustion are recommend.

  5. Operational cost minimization in cooling water systems

    Directory of Open Access Journals (Sweden)

    Castro M.M.

    2000-01-01

    Full Text Available In this work, an optimization model that considers thermal and hydraulic interactions is developed for a cooling water system. It is a closed loop consisting of a cooling tower unit, circulation pump, blower and heat exchanger-pipe network. Aside from process disturbances, climatic fluctuations are considered. Model constraints include relations concerning tower performance, air flowrate requirement, make-up flowrate, circulating pump performance, heat load in each cooler, pressure drop constraints and climatic conditions. The objective function is operating cost minimization. Optimization variables are air flowrate, forced water withdrawal upstream the tower, and valve adjustment in each branch. It is found that the most significant operating cost is related to electricity. However, for cooled water temperatures lower than a specific target, there must be a forced withdrawal of circulating water and further makeup to enhance the cooling tower capacity. Additionally, the system is optimized along the months. The results corroborate the fact that the most important variable on cooling tower performance is not the air temperature itself, but its humidity.

  6. Parametric study of minimal cost SPS systems

    Energy Technology Data Exchange (ETDEWEB)

    Love, A.W.

    1982-01-01

    In this study, a cost function for a single solar power satellite (SPS) system is developed using the recently defined magnetron-powered reference system as a model. By assuming a one-parameter Hansen distribution of microwave energy over the spacetenna, it is shown that the cost of delivered power is a function of only two variables. One is the Hansen parameter, h, while the other is the power density level at which the rectenna intercepts the power beam of the spacetenna. This simplification makes it possible to compute a family of curves of cost per kilowatt versus rectenna intercept level with h as a parameter. These curves all have minima and it is apparent that the current reference system, at $2110/kW, is not a minimum power cost system. For this particular system h is approximately 2.4 and the minimum in the cost function is actually $1990/kW. This 6% decrease in cost of power can be realized by making only one simple change in the design; the rectenna diameter must be decreased in order to intercept the power beam at the -8.3 dB level instead of the -13.6 dB level. Although the absolute minimum cost of power, about $1930/kW, occurs for uniform illumination of the spacetenna (h = 0), it turns out that the system with the least overall total cost occurs for h = 3.2, corresponding to a -27 dB sidelobe level.

  7. Implementation of laboratory practice with minimal cost

    Directory of Open Access Journals (Sweden)

    Idalberto Tamayo Ávila

    2015-06-01

    Full Text Available (Received: 2015/05/04 - Accepted: 2015/06/15In this work is reported an initiative to implement 24 assembly laboratories for General Physics, Applied Physics and Heat and Electromagnetism, in the premises of the Universidad Tecnológica Equinoccial (Santo Domingo, Ecuador. For this purpose three student memoires where designed and performed with unused, stored equipment, plus some additional material coming from students contribution. Each practice was set up and validated for teaching purposes with the methods of calculation errors and linear regression. This work saved the institution $16,369.57 compared with the cost of buying a commercial set for the laboratory.

  8. Restoration ecology: two-sex dynamics and cost minimization.

    Directory of Open Access Journals (Sweden)

    Ferenc Molnár

    Full Text Available We model a spatially detailed, two-sex population dynamics, to study the cost of ecological restoration. We assume that cost is proportional to the number of individuals introduced into a large habitat. We treat dispersal as homogeneous diffusion in a one-dimensional reaction-diffusion system. The local population dynamics depends on sex ratio at birth, and allows mortality rates to differ between sexes. Furthermore, local density dependence induces a strong Allee effect, implying that the initial population must be sufficiently large to avert rapid extinction. We address three different initial spatial distributions for the introduced individuals; for each we minimize the associated cost, constrained by the requirement that the species must be restored throughout the habitat. First, we consider spatially inhomogeneous, unstable stationary solutions of the model's equations as plausible candidates for small restoration cost. Second, we use numerical simulations to find the smallest rectangular cluster, enclosing a spatially homogeneous population density, that minimizes the cost of assured restoration. Finally, by employing simulated annealing, we minimize restoration cost among all possible initial spatial distributions of females and males. For biased sex ratios, or for a significant between-sex difference in mortality, we find that sex-specific spatial distributions minimize the cost. But as long as the sex ratio maximizes the local equilibrium density for given mortality rates, a common homogeneous distribution for both sexes that spans a critical distance yields a similarly low cost.

  9. Minimizing communication cost among distributed controllers in software defined networks

    Science.gov (United States)

    Arlimatti, Shivaleela; Elbreiki, Walid; Hassan, Suhaidi; Habbal, Adib; Elshaikh, Mohamed

    2016-08-01

    Software Defined Networking (SDN) is a new paradigm to increase the flexibility of today's network by promising for a programmable network. The fundamental idea behind this new architecture is to simplify network complexity by decoupling control plane and data plane of the network devices, and by making the control plane centralized. Recently controllers have distributed to solve the problem of single point of failure, and to increase scalability and flexibility during workload distribution. Even though, controllers are flexible and scalable to accommodate more number of network switches, yet the problem of intercommunication cost between distributed controllers is still challenging issue in the Software Defined Network environment. This paper, aims to fill the gap by proposing a new mechanism, which minimizes intercommunication cost with graph partitioning algorithm, an NP hard problem. The methodology proposed in this paper is, swapping of network elements between controller domains to minimize communication cost by calculating communication gain. The swapping of elements minimizes inter and intra communication cost among network domains. We validate our work with the OMNeT++ simulation environment tool. Simulation results show that the proposed mechanism minimizes the inter domain communication cost among controllers compared to traditional distributed controllers.

  10. The environmental cost of subsistence: Optimizing diets to minimize footprints.

    Science.gov (United States)

    Gephart, Jessica A; Davis, Kyle F; Emery, Kyle A; Leach, Allison M; Galloway, James N; Pace, Michael L

    2016-05-15

    The question of how to minimize monetary cost while meeting basic nutrient requirements (a subsistence diet) was posed by George Stigler in 1945. The problem, known as Stigler's diet problem, was famously solved using the simplex algorithm. Today, we are not only concerned with the monetary cost of food, but also the environmental cost. Efforts to quantify environmental impacts led to the development of footprint (FP) indicators. The environmental footprints of food production span multiple dimensions, including greenhouse gas emissions (carbon footprint), nitrogen release (nitrogen footprint), water use (blue and green water footprint) and land use (land footprint), and a diet minimizing one of these impacts could result in higher impacts in another dimension. In this study based on nutritional and population data for the United States, we identify diets that minimize each of these four footprints subject to nutrient constraints. We then calculate tradeoffs by taking the composition of each footprint's minimum diet and calculating the other three footprints. We find that diets for the minimized footprints tend to be similar for the four footprints, suggesting there are generally synergies, rather than tradeoffs, among low footprint diets. Plant-based food and seafood (fish and other aquatic foods) commonly appear in minimized diets and tend to most efficiently supply macronutrients and micronutrients, respectively. Livestock products rarely appear in minimized diets, suggesting these foods tend to be less efficient from an environmental perspective, even when nutrient content is considered. The results' emphasis on seafood is complicated by the environmental impacts of aquaculture versus capture fisheries, increasing in aquaculture, and shifting compositions of aquaculture feeds. While this analysis does not make specific diet recommendations, our approach demonstrates potential environmental synergies of plant- and seafood-based diets. As a result, this study

  11. Cost-effectiveness of minimally invasive sacroiliac joint fusion

    Directory of Open Access Journals (Sweden)

    Cher DJ

    2015-12-01

    Full Text Available Daniel J Cher,1 Melissa A Frasco,2 Renée JG Arnold,2,3 David W Polly4,5 1Clinical Affairs, SI-BONE, Inc., San Jose, CA, USA; 2Division of Health Economics and Outcomes Research, Quorum Consulting, Inc., San Francisco, CA, USA; 3Department of Preventive Medicine, Icahn School of Medicine at Mount Sinai, New York, NY, USA; 4Department of Orthopaedic Surgery, University of Minnesota, Minneapolis, MN, USA; 5Department of Neurosurgery, University of Minnesota, Minneapolis, MN, USA Background: Sacroiliac joint (SIJ disorders are common in patients with chronic lower back pain. Minimally invasive surgical options have been shown to be effective for the treatment of chronic SIJ dysfunction. Objective: To determine the cost-effectiveness of minimally invasive SIJ fusion. Methods: Data from two prospective, multicenter, clinical trials were used to inform a Markov process cost-utility model to evaluate cumulative 5-year health quality and costs after minimally invasive SIJ fusion using triangular titanium implants or non-surgical treatment. The analysis was performed from a third-party perspective. The model specifically incorporated variation in resource utilization observed in the randomized trial. Multiple one-way and probabilistic sensitivity analyses were performed. Results: SIJ fusion was associated with a gain of approximately 0.74 quality-adjusted life years (QALYs at a cost of US$13,313 per QALY gained. In multiple one-way sensitivity analyses all scenarios resulted in an incremental cost-effectiveness ratio (ICER <$26,000/QALY. Probabilistic analyses showed a high degree of certainty that the maximum ICER for SIJ fusion was less than commonly selected thresholds for acceptability (mean ICER =$13,687, 95% confidence interval $5,162–$28,085. SIJ fusion provided potential cost savings per QALY gained compared to non-surgical treatment after a treatment horizon of greater than 13 years. Conclusion: Compared to traditional non-surgical treatments

  12. Minimization of electricity consumption cost of a typical factory

    International Nuclear Information System (INIS)

    The difference between the price of one Kilowatt-hour (KWh) during peak and normal hours was significantly high. The reduction in electricity consumption cost has drawn the attention towards optimal schedule. In this paper we developed a physical based optimization model that utilizes linear programming technique for minimizing electricity cost by rescheduling the specific load in such a way that all the requirements of the industry are fulfilled. The proposed model was implemented on load management problem of typical factory as a case study. The results showed that the significant reduction in peak electricity load was possible. As a result of rescheduling the load factor was improved that caused the reduction in the electricity consumption cost. Optimization, Mathematical Modeling, Load Management, Electricity Cost, Load Curve. (author)

  13. Minimal Cost of a Brownian Risk without Ruin

    CERN Document Server

    Luo, Shangzhen

    2011-01-01

    In this paper, we study a risk process modeled by a Brownian motion with drift (the diffusion approximation model). The insurance entity can purchase reinsurance to lower its risk and receive cash injections at discrete times to avoid ruin. Proportional reinsurance and excess-of-loss reinsurance are considered. The objective is to find the optimal reinsurance and cash injection strategy that minimizes the total cost to keep the company's surplus process non-negative, i.e. without ruin, where the cost function is defined as the total discounted value of the injections. The optimal solution is found explicitly by solving the according quasi-variational inequalities (QVIs).

  14. Application of trajectory optimization principles to minimize aircraft operating costs

    Science.gov (United States)

    Sorensen, J. A.; Morello, S. A.; Erzberger, H.

    1979-01-01

    This paper summarizes various applications of trajectory optimization principles that have been or are being devised by both government and industrial researchers to minimize aircraft direct operating costs (DOC). These costs (time and fuel) are computed for aircraft constrained to fly over a fixed range. Optimization theory is briefly outlined, and specific algorithms which have resulted from application of this theory are described. Typical results which demonstrate use of these algorithms and the potential savings which they can produce are given. Finally, need for further trajectory optimization research is presented.

  15. Minimization of the Transport Costs in Forestry by Linear Programing

    OpenAIRE

    Acar, H. Hulusi; GÜL, A. Uğur; Gümüş, Selçuk

    2000-01-01

    In forest management, transportation is a rather difficult, expensive and time-consuming activity. Transportation of logs from the forest to the landings has been achieved in various ways. Log transportation with minimum losses of quality and quantity and with minimum damage to the environment is a crucial matter in Turkey. The operation research methods for log operations have not been used in Turkey. The aim of this study was to minimize the total cost during logging operations by linea...

  16. Optimal footfall patterns for cost minimization in running.

    Science.gov (United States)

    Miller, Ross H; Hamill, Joseph

    2015-08-20

    Optimality in footfall pattern use is often studied in relation to running performance and injury risk. The typical variables assessed (metabolic cost, impact force) represent only two of many potential variables runners might want to minimize situationally. Here we used optimal control theory to predict optimal model-based running mechanics with 44 different cost functions. We tallied the frequency of different footfall patterns, then examined which patterns minimized which types of cost functions. When the model wore shoes, rearfoot striking (RFS) was predicted by 57% of the cost functions and was consistently optimal for functions related to whole-body energy expenditure and peak joint contact forces. No other footfall pattern was predicted by more than 25% of the functions. Non-RFS patterns tended to be optimal for functions that gave equal weight to all muscles, avoiding localized muscle fatigue. Non-RFS patterns were also predicted when minimizing average joint contact forces. Similar predictions were seen when the model ran barefoot, where RFS was optimal for 55% of the functions. The results suggest that RFS is the most versatile footfall pattern (optimal for the greatest number of goals), and may explain why RFS is the most common pattern in recreational shod runners. We argue that natural non-RFS runners are not necessarily behaving "sub-optimally", but rather may be optimizing their gaits on factors not tested here (e.g. comfort, which is difficult to quantify). In addition, switching from RFS to non-RFS may reduce the joint load accumulated during a run if speed and step length are maintained. PMID:25952545

  17. LEAN HEALTHCARE SUPPLY CHAIN MANAGEMENT: MINIMIZING WASTE AND COSTS

    Directory of Open Access Journals (Sweden)

    Catia M L Machado

    2014-12-01

    Full Text Available The purpose of this research is to investigate the management models applied in the supply chain providing services in healthcare organizations, considering the lenses of lean. The aim of this is to develop a model of supply chain management focusing on the identification and minimization of waste, assisting in decision making and contributing to the quality of services and as a consequence the reduction of the costs involved in healthcare supply chain. The philosophies of continuous improvement and lean techniques have a role to play in helping healthcare to provide quality service and support to reduce costs in the current budget constraints. In the supply chain of hospitals the financial costs can be around 40% of its budget (MASOUMI et al. 2012; SOUZA et al., 2013. This article sheds light on the improvement in decision making and the effect of reducing costs in the healthcare supply chain. In this sense, the research intend to expand knowledge related to supply chain management in the area of ​​provision of healthcare services through the use of the philosophy of continuous improvement and lean principles, helping healthcare to provide quality service within their current budget constraints.

  18. Transmission cost minimization strategies for wind-electric generating facilities

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez, R. [Northern States Power Company, Minneapolis, MN (United States)

    1997-12-31

    Integrating wind-electric generation facilities into existing power systems presents opportunities not encountered in conventional energy projects. Minimizing outlet cost requires probabilistic value-based analyses appropriately reflecting the wind facility`s operational characteristics. The wind resource`s intermittent nature permits relaxation of deterministic criteria addressing outlet configuration and capacity required relative to facility rating. Equivalent capacity ratings of wind generation facilities being a fraction of installed nameplate rating, outlet design studies contingency analyses can concentrate on this fractional value. Further, given its non-dispatchable, low capacity factor nature, a lower level of redundancy in outlet facilities is appropriate considering the trifling contribution to output unreliability. Further cost reduction opportunities arise from {open_quotes}wind speed/generator power output{close_quotes} and {open_quotes}wind speed/overhead conductor rating{close_quotes} functions` correlation. Proper analysis permits the correlation`s exploitation to safely increase line ratings. Lastly, poor correlation between output and utility load may permit use of smaller conductors, whose higher (mostly off-peak) losses are economically justifiable.

  19. Control at stability's edge minimizes energetic costs: expert stick balancing.

    Science.gov (United States)

    Milton, John; Meyer, Ryan; Zhvanetsky, Max; Ridge, Sarah; Insperger, Tamás

    2016-06-01

    Stick balancing on the fingertip is a complex voluntary motor task that requires the stabilization of an unstable system. For seated expert stick balancers, the time delay is 0.23 s, the shortest stick that can be balanced for 240 s is 0.32 m and there is a [Formula: see text]° dead zone for the estimation of the vertical displacement angle in the saggital plane. These observations motivate a switching-type, pendulum-cart model for balance control which uses an internal model to compensate for the time delay by predicting the sensory consequences of the stick's movements. Numerical simulations using the semi-discretization method suggest that the feedback gains are tuned near the edge of stability. For these choices of the feedback gains, the cost function which takes into account the position of the fingertip and the corrective forces is minimized. Thus, expert stick balancers optimize control with a combination of quick manoeuvrability and minimum energy expenditures. PMID:27278361

  20. A cost-minimization analysis of tissue-engineered constructs for corneal endothelial transplantation.

    Directory of Open Access Journals (Sweden)

    Tien-En Tan

    Full Text Available Corneal endothelial transplantation or endothelial keratoplasty has become the preferred choice of transplantation for patients with corneal blindness due to endothelial dysfunction. Currently, there is a worldwide shortage of transplantable tissue, and demand is expected to increase further with aging populations. Tissue-engineered alternatives are being developed, and are likely to be available soon. However, the cost of these constructs may impair their widespread use. A cost-minimization analysis comparing tissue-engineered constructs to donor tissue procured from eye banks for endothelial keratoplasty was performed. Both initial investment costs and recurring costs were considered in the analysis to arrive at a final tissue cost per transplant. The clinical outcomes of endothelial keratoplasty with tissue-engineered constructs and with donor tissue procured from eye banks were assumed to be equivalent. One-way and probabilistic sensitivity analyses were performed to simulate various possible scenarios, and to determine the robustness of the results. A tissue engineering strategy was cheaper in both investment cost and recurring cost. Tissue-engineered constructs for endothelial keratoplasty could be produced at a cost of US$880 per transplant. In contrast, utilizing donor tissue procured from eye banks for endothelial keratoplasty required US$3,710 per transplant. Sensitivity analyses performed further support the results of this cost-minimization analysis across a wide range of possible scenarios. The use of tissue-engineered constructs for endothelial keratoplasty could potentially increase the supply of transplantable tissue and bring the costs of corneal endothelial transplantation down, making this intervention accessible to a larger group of patients. Tissue-engineering strategies for corneal epithelial constructs or other tissue types, such as pancreatic islet cells, should also be subject to similar pharmacoeconomic analyses.

  1. Recent Theoretical Approaches to Minimal Artificial Cells

    Directory of Open Access Journals (Sweden)

    Fabio Mavelli

    2014-05-01

    Full Text Available Minimal artificial cells (MACs are self-assembled chemical systems able to mimic the behavior of living cells at a minimal level, i.e. to exhibit self-maintenance, self-reproduction and the capability of evolution. The bottom-up approach to the construction of MACs is mainly based on the encapsulation of chemical reacting systems inside lipid vesicles, i.e. chemical systems enclosed (compartmentalized by a double-layered lipid membrane. Several researchers are currently interested in synthesizing such simple cellular models for biotechnological purposes or for investigating origin of life scenarios. Within this context, the properties of lipid vesicles (e.g., their stability, permeability, growth dynamics, potential to host reactions or undergo division processes… play a central role, in combination with the dynamics of the encapsulated chemical or biochemical networks. Thus, from a theoretical standpoint, it is very important to develop kinetic equations in order to explore first—and specify later—the conditions that allow the robust implementation of these complex chemically reacting systems, as well as their controlled reproduction. Due to being compartmentalized in small volumes, the population of reacting molecules can be very low in terms of the number of molecules and therefore their behavior becomes highly affected by stochastic effects both in the time course of reactions and in occupancy distribution among the vesicle population. In this short review we report our mathematical approaches to model artificial cell systems in this complex scenario by giving a summary of three recent simulations studies on the topic of primitive cell (protocell systems.

  2. Cost-minimization of mabthera intravenous versus subcutaneous administration

    NARCIS (Netherlands)

    Bax, P.; Postma, M.J.

    2013-01-01

    Objectives: To identify and compare all costs related to preparing and administrating MabThera for the intravenous and subcutaneous formulations in Dutch hematological patients. The a priori notion is that the costs of subcutaneous MabThera injections are lower compared to intravenous infusion due t

  3. Simple steps help minimize costs, risks in project contracts

    International Nuclear Information System (INIS)

    Contrary to prevailing opinion, risks and project financing costs can be higher for lump sum (LS) project contracts than under reimbursable-type contracts. An element-by-element analysis of the risks and costs associated with a project enables investors to develop variations of reimbursable contracts. Project managers can use this three-step procedure, along with other recommendations, to measure the hidden project costs and risks associated with LS contracts. The author bases his conclusions on case studies of recent projects in the petroleum refining and petrochemical industries. The findings, however, are general enough to be applicable in other industrial sectors

  4. A Nonparametric Analysis of Cost Minimization and Profit Maximization Behavior for a Sample of Kansas Farms

    OpenAIRE

    Moghnieh, Ghassan A.; Featherstone, Allen M.; Goodwin, Barry K.

    1991-01-01

    This study investigates nonparametrically the optimizing behavior of a sample of 289 Kansas farms under profit-maximizing and cost-minimizing hypotheses. The results do not support strict adherence to either optimization hypothesis. However, evidence against cost-minimizing behavior seems to be far less substantial than that against profit-maximizing behavior.

  5. Minimizing the cost of subsea developments through technological innovation

    International Nuclear Information System (INIS)

    The paper summarizes the results of an extensive study carried out for the UK Government. This assessed the cost and economic impact of technological innovation on subsea and floating developments in the UKCS. The study covered, innovations that could be applied to subsea developments to significantly reduce cost, including multiwell completions, composite pipelines, compartmented pipelines, pipeline specification breaking and autonomous control systems. Cost and economic models were used to assess the economic impact of technological innovation on marginal field developments. The results of these assessments were drawn up as a series of ranking lists designed to assist manufacturers and suppliers in establishing priorities for research and development funding. The study also explored the potential UKCS and World market for innovative subsea technologies and quantified the research and development required to bring key innovations into commercial use

  6. Minimization of transmission cost in decentralized control systems

    Science.gov (United States)

    Wang, S.-H.; Davison, E. J.

    1978-01-01

    This paper considers the problem of stabilizing a linear time-invariant multivariable system by using local feedback controllers and some limited information exchange among local stations. The problem of achieving a given degree of stability with minimum transmission cost is solved.

  7. Minimalism

    CERN Document Server

    Obendorf, Hartmut

    2009-01-01

    The notion of Minimalism is proposed as a theoretical tool supporting a more differentiated understanding of reduction and thus forms a standpoint that allows definition of aspects of simplicity. This book traces the development of minimalism, defines the four types of minimalism in interaction design, and looks at how to apply it.

  8. Cost-effectiveness of minimally invasive sacroiliac joint fusion [Corrigendum

    OpenAIRE

    Cher, Daniel

    2016-01-01

    Cher DJ, Frasco MA, Arnold RJ, Polly DW. Clinicoecon Outcomes Res. 2016;8:1–14.Daniel J Cher is an SI-BONE employee. Renee JG Arnold and Melissa A Frasco are employees of Quorum Consulting, hired by SI-BONE to help prepare and evaluate the cost-utility model. David Polly is an investigator in clinical research studies sponsored by SI-BONE but has no financial interest in the company. The authors report no other conflicts of interest in this work.View original article by Cher et al.

  9. Cost-effectiveness of minimally invasive sacroiliac joint fusion [Corrigendum

    Directory of Open Access Journals (Sweden)

    Cher DJ

    2016-06-01

    Full Text Available Cher DJ, Frasco MA, Arnold RJ, Polly DW. Clinicoecon Outcomes Res. 2016;8:1–14.Daniel J Cher is an SI-BONE employee. Renee JG Arnold and Melissa A Frasco are employees of Quorum Consulting, hired by SI-BONE to help prepare and evaluate the cost-utility model. David Polly is an investigator in clinical research studies sponsored by SI-BONE but has no financial interest in the company. The authors report no other conflicts of interest in this work.View original article by Cher et al.

  10. Minimization of the energy costs for operating magnetic tunnel junctions

    Science.gov (United States)

    Farhat, Ilyas A. H.; Gale, E.; Isakovic, A. F.

    2015-03-01

    Increasing prospects of utilizing the STT-MRAM calls for the re-assessment of the overall energy (power) cost of operating magnetic tunnel junctions and related elements. This motivates our design, nanofabrication and characterization of simple tri-layer magnetic tunnel junctions which show measurable decrease in the operating energy cost. The MTJs we report about rely on nanoengineering interfaces between the insulating and magnetic layers in such a way that the area of the hysteresis loops can be controlled in one or both magnetic layers. Our TMR coefficient ranges from 45% to 130%, depending on the MTJ layer materials, and can be anticipated to be further increased. We also report the study of the TMR dependence on the RA product, as an important interface parameter. Lastly, we present an analysis of MTJ parameters affected by our approach and a perspective on further improvements, focusing on the device design parameters relevant for the integration of this type of MTJs. This work is supported by the SRC-ATIC Grant 2012-VJ-2335. A part of this work is being performed at Cornell University CNF, a member of NNIN. We thank CNF staff for the support.

  11. Algorithm for Delay-Constrained Minimal Cost Group Multicasting

    Institute of Scientific and Technical Information of China (English)

    SUN Yugeng; WANG Yanlin; YAN Xinfang

    2005-01-01

    Group multicast routing algorithms satisfying quality of service requirements of real-time applications are essential for high-speed networks. A heuristic algorithm was presented for group multicast routing with bandwidth and delay constrained. A new metric was designed as a function of available bandwidth and delay of link. And source-specific routing trees for each member were generated in the algorithm by using the metric, which satisfy member′s bandwidth and end-to-end delay requirements. Simulations over random network were carried out to compare the performance of the proposed algorithm with that from literature.Experimental results show that the algorithm performs better in terms of network cost and ability in constructing feasible multicast trees for group members. Moreover,the algorithm can avoid link blocking and enhance the network behavior efficiently.

  12. MINIMIZING WASTE AND COST IN DISPOSITION OF LEGACY RESIDUES

    International Nuclear Information System (INIS)

    Research is being conducted at the Los Alamos National Laboratory (LANL) which is directed toward development of a quantitative basis for disposition of actinide-bearing process residues (both legacy residues and residues generated from ongoing programmatic operations). This research is focused in two directions: (1) identifying minimum negative consequence (waste, dose, cost) dispositions working within regulatory safeguards termination criteria, and (2) evaluating logistics/consequences of across-the-board residue discards such as authorized at Rocky Flats under a safeguards termination variance. The first approach emphasizes Laboratory commitments to environmental stewardship, worker safety, and fiscal responsibility. This approach has been described as the Plutonium Disposition Methodology (PDM) in deference to direction provided by DOE Albuquerque. The second approach is born of the need to expedite removal of residues from storage for programmatic and reasons and residue storage safety concerns. Any disposition path selected must preserve the legal distinction between residues as Special Nuclear Material (SNM) and discardable materials as waste in order to insure the continuing viability of Laboratory plutonium processing facilities for national security operations

  13. Minimal model for stem-cell differentiation

    Science.gov (United States)

    Goto, Yusuke; Kaneko, Kunihiko

    2013-09-01

    To explain the differentiation of stem cells in terms of dynamical systems theory, models of interacting cells with intracellular protein expression dynamics are analyzed and simulated. Simulations were carried out for all possible protein expression networks consisting of two genes under cell-cell interactions mediated by the diffusion of a protein. Networks that show cell differentiation are extracted and two forms of symmetric differentiation based on Turing's mechanism and asymmetric differentiation are identified. In the latter network, the intracellular protein levels show oscillatory dynamics at a single-cell level, while cell-to-cell synchronicity of the oscillation is lost with an increase in the number of cells. Differentiation to a fixed-point-type behavior follows with a further increase in the number of cells. The cell type with oscillatory dynamics corresponds to a stem cell that can both proliferate and differentiate, while the latter fixed-point type only proliferates. This differentiation is analyzed as a saddle-node bifurcation on an invariant circle, while the number ratio of each cell type is shown to be robust against perturbations due to self-consistent determination of the effective bifurcation parameter as a result of the cell-cell interaction. Complex cell differentiation is designed by combing these simple two-gene networks. The generality of the present differentiation mechanism, as well as its biological relevance, is discussed.

  14. Minimal model for stem-cell differentiation.

    Science.gov (United States)

    Goto, Yusuke; Kaneko, Kunihiko

    2013-09-01

    To explain the differentiation of stem cells in terms of dynamical systems theory, models of interacting cells with intracellular protein expression dynamics are analyzed and simulated. Simulations were carried out for all possible protein expression networks consisting of two genes under cell-cell interactions mediated by the diffusion of a protein. Networks that show cell differentiation are extracted and two forms of symmetric differentiation based on Turing's mechanism and asymmetric differentiation are identified. In the latter network, the intracellular protein levels show oscillatory dynamics at a single-cell level, while cell-to-cell synchronicity of the oscillation is lost with an increase in the number of cells. Differentiation to a fixed-point-type behavior follows with a further increase in the number of cells. The cell type with oscillatory dynamics corresponds to a stem cell that can both proliferate and differentiate, while the latter fixed-point type only proliferates. This differentiation is analyzed as a saddle-node bifurcation on an invariant circle, while the number ratio of each cell type is shown to be robust against perturbations due to self-consistent determination of the effective bifurcation parameter as a result of the cell-cell interaction. Complex cell differentiation is designed by combing these simple two-gene networks. The generality of the present differentiation mechanism, as well as its biological relevance, is discussed. PMID:24125305

  15. A preventive maintenance and minimal repair costs model with interest rate

    Science.gov (United States)

    Lewaherilla, Norisca; Pasaribu, Udjianna S.; Husniah, Hennie; Supriantna, Asep K.

    2016-02-01

    This paper deals with minimal repair and sequential imperfect preventive maintenance (imperfect PM) for a fishing vessel. Failure that occur at random times rectified by minimal repair, result minimal repair cost. We add the downtime cost to modify the cost model previously discussed by Jiang and Murthy (2008). That cost is intended as a cost of losses when the vessel is being repaired. Because of the time value of money, each cost should be subject to interest rate. The performance measure is the minimization of the expected total maintenance cost during a certain period. The decision variables are the number of imperfect PM and the level of preventive actions. We assume the distribution of first failure rate is Weibull and follows a nonhomogeneous Poisson process (NHPP). We give the comparison of maintenance costs between the cost resulting from our model and that from the previous model. The previous model is nested in our model and the result shows that in our model a higher interest rate will increase the maintenance cost.

  16. Farm-level nonparametric analysis of cost-minimization and profit-maximization behavior

    OpenAIRE

    Allen M. Featherstone; Moghnieh, Ghassan A.; Goodwin, Barry K.

    1995-01-01

    This study investigates non-parametrically the optimizing behavior of a sample of 289 Kansas farms under profit-maximization and cost-minimization hypotheses. The study uses both deterministic and stochastic non-parametric tests. The deterministic results do not support strict adherence to either optimization hypothesis. The stochastic tests suggest that all 289 farms fail the profit-maximization hypothesis, whereas 171 farms failed the cost-minimization hypothesis. Allowing for non-regressiv...

  17. Geometric theory predicts bifurcations in minimal wiring cost trees in biology are flat

    OpenAIRE

    Yihwa Kim; Robert Sinclair; Nol Chindapol; Jaap A Kaandorp; Erik De Schutter

    2012-01-01

    The complex three-dimensional shapes of tree-like structures in biology are constrained by optimization principles, but the actual costs being minimized can be difficult to discern. We show that despite quite variable morphologies and functions, bifurcations in the scleractinian coral Madracis and in many different mammalian neuron types tend to be planar. We prove that in fact bifurcations embedded in a spatial tree that minimizes wiring cost should lie on planes. This biologically motivated...

  18. A Comparison of Mixed-Integer Programming Models for Nonconvex Piecewise Linear Cost Minimization Problems

    OpenAIRE

    Keely L. Croxton; Bernard Gendron; Thomas L. Magnanti

    2003-01-01

    We study a generic minimization problem with separable nonconvex piecewise linear costs, showing that the linear programming (LP) relaxation of three textbook mixed-integer programming formulations each approximates the cost function by its lower convex envelope. We also show a relationship between this result and classical Lagrangian duality theory.

  19. Multiagent-based Distributed Control for Operation Cost Minimization of Droop Controlled DC Microgrid Using Incremental Cost Consensus

    DEFF Research Database (Denmark)

    Li, Chendan; Quintero, Juan Carlos Vasquez; Guerrero, Josep M.

    In this paper, a multiagent based distributed control is proposed for DC microgrid to minimize the operation cost. The power of each distributed generator (DG) is dispatched in a distributed manner in a multiagent system by means of voltage scheduling. Every DG unit is taken as an agent, and they...... share the load corresponding to the operation cost of all the units in the system with only communication with direct neighbors through incremental cost consensus. The power regulation according to the power reference generated by consensus is implemented through voltage scheduling in local primary...... controllers. Simulation verification shows that total operation cost of the DC microgrid is successfully reduced though the proposed method....

  20. Minimization of Storage Cost in Distributed Storage Systems with Repair Consideration

    OpenAIRE

    Yu, Quan; Shum, Kenneth W.; Sung, Chi Wan

    2011-01-01

    In a distributed storage system, the storage costs of different storage nodes, in general, can be different. How to store a file in a given set of storage nodes so as to minimize the total storage cost is investigated. By analyzing the min-cut constraints of the information flow graph, the feasible region of the storage capacities of the nodes can be determined. The storage cost minimization can then be reduced to a linear programming problem, which can be readily solved. Moreover, the tradeo...

  1. Eliminating Hairy Cell Leukemia Minimal Residual Disease

    Science.gov (United States)

    In this trial, patients with hairy cell leukemia who have disease-related symptoms that require treatment will be randomly assigned to receive cladribine with either concurrent rituximab or rituximab at least 6 months after completing cladribine therapy.

  2. Multiagent-based Distributed Control for Operation Cost Minimization of Droop Controlled DC Microgrid Using Incremental Cost Consensus

    OpenAIRE

    Li, Chendan; Quintero, Juan Carlos Vasquez; Guerrero, Josep M.

    2015-01-01

    In this paper, a multiagent based distributedcontrol is proposed for DC microgrid to minimize the operationcost. The power of each distributed generator (DG) is dispatchedin a distributed manner in a multiagent system by means ofvoltage scheduling. Every DG unit is taken as an agent, and theyshare the load corresponding to the operation cost of all the unitsin the system with only communication with direct neighborsthrough incremental cost consensus. The power regulationaccording to the power...

  3. Systems Biology Perspectives on Minimal and Simpler Cells

    Science.gov (United States)

    Xavier, Joana C.; Patil, Kiran Raosaheb

    2014-01-01

    SUMMARY The concept of the minimal cell has fascinated scientists for a long time, from both fundamental and applied points of view. This broad concept encompasses extreme reductions of genomes, the last universal common ancestor (LUCA), the creation of semiartificial cells, and the design of protocells and chassis cells. Here we review these different areas of research and identify common and complementary aspects of each one. We focus on systems biology, a discipline that is greatly facilitating the classical top-down and bottom-up approaches toward minimal cells. In addition, we also review the so-called middle-out approach and its contributions to the field with mathematical and computational models. Owing to the advances in genomics technologies, much of the work in this area has been centered on minimal genomes, or rather minimal gene sets, required to sustain life. Nevertheless, a fundamental expansion has been taking place in the last few years wherein the minimal gene set is viewed as a backbone of a more complex system. Complementing genomics, progress is being made in understanding the system-wide properties at the levels of the transcriptome, proteome, and metabolome. Network modeling approaches are enabling the integration of these different omics data sets toward an understanding of the complex molecular pathways connecting genotype to phenotype. We review key concepts central to the mapping and modeling of this complexity, which is at the heart of research on minimal cells. Finally, we discuss the distinction between minimizing the number of cellular components and minimizing cellular complexity, toward an improved understanding and utilization of minimal and simpler cells. PMID:25184563

  4. Membrane electrolytic cell for minimizing hypochlorite and chlorate formation

    International Nuclear Information System (INIS)

    An electrolytic cell for the electrolysis of an alkali metal chloride brine is comprised of an anode compartment and a cathode compartment separated by a cation exchange membrane. The anode is comprised of an unflattened expanded structure of a valve metal selected from the group consisting of titanium, tantalum, niobium, and alloys thereof. At least one side of the anode has as the electrochemically active surface an electrodeposited layer of a valve metal oxide. A plurality of cracks traverse the electrodeposited layer and a coating of a platinum metal group oxide covers the electrodeposited layer and substantially fills the cracks. The cationic exchange membrane is comprised of a laminated structure having a first surface adapted to contact an anolyte in which the ion exchange groups are predominately sulfonic acid groups. The first surface is also in contact with the electrochemically active surface of the anode. A second surface of the cation exchange membrane, adapted to contact a catholyte, has ion exchange groups which are predominately carboxylic acid groups. The cathode positioned in the cathode compartment is spaced apart from the cation exchange membrane. The cell operates with both a low chlorine overvoltage and a low oxygen overvoltage. During electrolysis of alkali metal chloride brines, the formation of hypochlorite and chlorate ions is minimized and the alkali metal hydroxides produced have low chlorate concentrations and are suitable for use without further treatment in chlorate-sensitive applications. Spent brine treatment is simplified and at reduced costs

  5. Two-Agent Scheduling to Minimize the Maximum Cost with Position-Dependent Jobs

    Directory of Open Access Journals (Sweden)

    Long Wan

    2015-01-01

    Full Text Available This paper investigates a single-machine two-agent scheduling problem to minimize the maximum costs with position-dependent jobs. There are two agents, each with a set of independent jobs, competing to perform their jobs on a common machine. In our scheduling setting, the actual position-dependent processing time of one job is characterized by variable function dependent on the position of the job in the sequence. Each agent wants to fulfil the objective of minimizing the maximum cost of its own jobs. We develop a feasible method to achieve all the Pareto optimal points in polynomial time.

  6. Cloud Computing-An Ultimate Technique to Minimize Computing cost for Developing Countries

    OpenAIRE

    Narendra Kumar; Shikha Jain

    2012-01-01

    The presented paper deals with how remotely managed computing and IT resources can be beneficial in the developing countries like India and Asian sub-continent countries. This paper not only defines the architectures and functionalities of cloud computing but also indicates strongly about the current demand of Cloud computing to achieve organizational and personal level of IT supports in very minimal cost with high class flexibility. The power of cloud can be used to reduce the cost of IT - r...

  7. A cost-minimization analysis of combination therapy in hypertension: fixed-dose vs extemporary combinations

    OpenAIRE

    Marco Bellone; Pierluigi Sbarra

    2013-01-01

    BACKGROUND: Cardiovascular disease management and prevention represent the leading cost driver in Italian healthcare expenditure. In order to reach the target blood pressure, a large majority of patients require simultaneous administration of multiple antihypertensive agents.OBJECTIVE: To assess the economic impact of the use of fixed dose combinations of antihypertensive agents, compared to the extemporary combination of the same principles.METHODS: A cost minimization analysis was conducted...

  8. Geometric theory predicts bifurcations in minimal wiring cost trees in biology are flat

    NARCIS (Netherlands)

    Y. Kim; R. Sinclair; N. Chindapol; J.A. Kaandorp; E. De Schutter

    2012-01-01

    The complex three-dimensional shapes of tree-like structures in biology are constrained by optimization principles, but the actual costs being minimized can be difficult to discern. We show that despite quite variable morphologies and functions, bifurcations in the scleractinian coral Madracis and i

  9. Technological Minimalism: A Cost-Effective Alternative for Course Design and Development.

    Science.gov (United States)

    Lorenzo, George

    2001-01-01

    Discusses the use of minimum levels of technology, or technological minimalism, for Web-based multimedia course content. Highlights include cost effectiveness; problems with video streaming, the use of XML for Web pages, and Flash and Java applets; listservs instead of proprietary software; and proper faculty training. (LRW)

  10. Multiagent based Distributed Control for Operation Cost Minimization of Droop Controlled AC Microgrid Using Incremental Cost Consensus

    DEFF Research Database (Denmark)

    Li, Chendan; Firoozabadi, Mehdi Savaghebi; Quintero, Juan Carlos Vasquez;

    2015-01-01

    sharing based on the power rating. With various types of distributed generator (DG) units in the system, factors that closely related to the operation cost, such as fuel cost and efficiencies of the generator should be taken into account in order to improve the efficiency of the whole system....... In this paper, a multiagent based distributed method is proposed to minimize operation cost of the AC microgrid. Each DG is acting as an agent which regulates the power individually using proposed frequency scheduling method. Optimal power command is obtained through carefully designed consensus algorithm...... with only light communication between neighboring agents. Case studies verified that the proposed control strategy can effectively reduce the operation cost....

  11. A Systematic Procedure for the Generation of Cost-Minimized Designs

    DEFF Research Database (Denmark)

    Becker, Peter W.; Jarkler, Bjorn

    1972-01-01

    faces the following problem: How should he proceed to find the combination of grades that will give him the desired manufacturing yield at minimum product cost? We discuss the problem and suggest a policy by which the designer, with a reasonable computational effort, can find a set of ``good......We present a procedure for the generation of cost-minimized designs of circuits and systems. Suppose a designer has decided upon the topology of his product. Also suppose he knows the cost and quality of the different grades of the N components required to implement the product. The designer then...

  12. Current trends in treatment of obesity in Karachi and possibilities of cost minimization.

    Science.gov (United States)

    Hussain, Mirza Izhar; Naqvi, Baqir Shyum

    2015-03-01

    Our study finds out drug usage trends in over weight and obese patients without any compelling indications in Karachi, looks for deviations of current practices from evidence based antihypertensive therapeutic guidelines and identifies not only cost minimization opportunities but also communication strategies to improve patients' awareness and compliance to achieve therapeutic goal. In present study two sets were used. Randomized stratified independent surveys were conducted in hospital doctors and family physicians (general practitioners), using pretested questionnaires. Sample size was 100. Statistical analysis was conducted on Statistical Package for Social Science (SPSS). Opportunities of cost minimization were also analyzed. One the basis of doctors' feedback, preference is given to non-pharmacologic management of obesity. Mass media campaign and media usage were recommended to increase patients awareness and patients' education along with strengthening family support systems was recommended for better compliance of the patients to doctor's advice. Local therapeutic guidelines for weight reduction were not found. Feedbacks showed that global therapeutic guidelines were followed by the doctors practicing in the community and hospitals in Karachi. However, high price branded drugs were used instead of low priced generic therapeutic equivalents. Patient's education is required for better awareness and improving patients' compliance. The doctors found preferring brand leaders instead of low cost options. This trend increases cost of therapy by 0.59 to 4.17 times. Therefore, there are great opportunities for cost minimization by using evidence-based clinically effective and safe medicines. PMID:25796152

  13. Cost Minimization Model of Gas Transmission Line for Indonesian SIJ Pipeline Network

    Directory of Open Access Journals (Sweden)

    Septoratno Siregar

    2003-05-01

    Full Text Available Optimization of Indonesian SIJ gas pipeline network is being discussed here. Optimum pipe diameters together with the corresponding pressure distribution are obtained from minimization of total cost function consisting of investment and operating costs and subjects to some physical (Panhandle A and Panhandle B equations constraints. Iteration technique based on Generalized Steepest-Descent and fourth order Runge-Kutta method are used here. The resulting diameters from this continuous optimization are then rounded to the closest available discrete sizes. We have also calculated toll fee along each segment and safety factor of the network by determining the pipe wall thickness, using ANSI B31.8 standard. Sensitivity analysis of toll fee for variation of flow rates is shown here. The result will gives the diameter and compressor size and compressor location that feasible to use for the SIJ pipeline project. The Result also indicates that the east route cost relatively less expensive than the west cost.

  14. Minimization of Inventory & Transportation Cost Of an Industry”-A Supply Chain Optimization

    Directory of Open Access Journals (Sweden)

    Nonihal Singh Dhakry

    2013-09-01

    Full Text Available In this paper a study on three in-stock strategies – flow-through, regional and single DC central stock and developed a simple transportation-inventory model in order to compare their total costs is done. We have also described a distribution model proposed by in which the model is formulated as a non-linear integer optimization problem. Due to the non-linearity of the inventory cost in the objective function, two heuristics and an exact algorithm is proposed in order to solve the problem. The results obtained from the transportation-inventory models show that the single DC and regional central stock strategies are more cost-efficient respectively compared to the flow-through approach. It is recommended to take the single DC and the regional central stock strategies for slow moving and emanding products respectively: Minimizing inventory & transportation cost of an industry: a supply chain optimization

  15. Single-machine batch scheduling minimizing weighted flow times and delivery costs with job release times

    Directory of Open Access Journals (Sweden)

    Amir Ebrahimzadeh Pilerood

    2012-04-01

    Full Text Available This paper addresses scheduling a set of weighted jobs on a single machine in presence of release date for delivery in batches to customers or to other machines for further processing. The problem is a natural extension of minimizing the sum of weighted flow times by considering the possibility of delivering jobs in batches and introducing batch delivery costs. The classical problem is NP-hard and then the extended version of the problem is NP-hard. The objective function is that of minimizing the sum of weighted flow times and delivery costs. The extended problem arises in a real supply chain network by cooperation between two layers of chain. Structural properties of the problem are investigated and used to devise a branch-and-bound solution scheme. Computational experiments show the efficiency of suggested algorithm for solving instances up to 40 jobs.

  16. Shuffled Frog Leaping Algorithm for minimizing total holding cost with tardy jobs in Job shop scheduling

    Directory of Open Access Journals (Sweden)

    G. Ramya

    2013-08-01

    Full Text Available In job shop scheduling problems, n jobs have to be processed on m different machines. Each job consists of a sequence of tasks that have to be processed during an uninterrupted time period of a fixed length on a given machine. This paper deals with the job shop scheduling problem (JSP of minimizing the total holding cost with consideration of tardy jobs using Shuffled Frog Leaping Algorithm. Research results from several benchmark problems with different sizes, which are commonly used for optimizing the scheduling objectives, solved by the proposed algorithms are reported. Shuffled Frog Leaping Algorithm gives better results compared with literature results in terms of total holding cost.

  17. Integrated Mobility and Service Management for Network Cost Minimization in Wireless Mesh Networks

    OpenAIRE

    Li, Yinan

    2012-01-01

    In this dissertation research, we design and analyze integrated mobility and service manage- ment for network cost minimization in Wireless Mesh Networks (WMNs). We first investigate the problem of mobility management in WMNs for which we propose two efficient per-user mobility management schemes based on pointer forwarding, and then a third one that integrates routing- based location update and pointer forwarding for further performance improvement. We further study integrate...

  18. A Cost-Minimization Analysis of the Angioseal Vascular Closure Device following Percutaneous Coronary Intervention

    OpenAIRE

    Resnic, Frederic S.; Arora, Nipun; Matheny, Michael; Reynolds, Matthew R.

    2007-01-01

    The Angioseal vascular closure device has been shown to be safe and effective in reducing the time to hemostasis following percutaneous coronary intervention (PCI). The health economic implications of routinely using Angioseal after PCI have not been explored. We performed a cost-minimization analysis comparing routine Angioseal use after PCI to mechanical compression using a decision analytic model. The relative probabilities of 7 vascular access complications were derived from pooled analys...

  19. A cost-minimization analysis of combination therapy in hypertension: fixed-dose vs extemporary combinations

    Directory of Open Access Journals (Sweden)

    Marco Bellone

    2013-12-01

    Full Text Available BACKGROUND: Cardiovascular disease management and prevention represent the leading cost driver in Italian healthcare expenditure. In order to reach the target blood pressure, a large majority of patients require simultaneous administration of multiple antihypertensive agents.OBJECTIVE: To assess the economic impact of the use of fixed dose combinations of antihypertensive agents, compared to the extemporary combination of the same principles.METHODS: A cost minimization analysis was conducted to determine the pharmaceutical daily cost of five fixed dose combinations (olmesartan 20 mg + amlodipine 5 mg, perindopril 5 mg + amlodipine 5 mg, enalapril 20 mg + lercanidipine 10 mg, felodipine 5 mg + ramipril 5 mg, and delapril 30 mg + manidipine 10 mg compared with extemporary combination of the same principles in the perspective of the Italian NHS. Daily acquisition costs are estimated based on current Italian prices and tariffs.RESULTS: In three cases the use of fixed‑dose combination instead of extemporary combination induces a lower daily cost. Fixed combination treatment with delapril 30 mg + manidipine 10 mg induces greater cost savings for the National Health System (95,47 €/pts/year, as compared to free drugs combination therapy.CONCLUSIONS: Compared with free drug combinations, fixed‑dose combinations of antihypertensive agents are associated with lower daily National Health Service acquisition costs.http://dx.doi.org/10.7175/fe.v14i4.886

  20. Cost minimization analysis of different growth hormone pen devices based on time-and-motion simulations

    Directory of Open Access Journals (Sweden)

    Kim Jaewhan

    2010-04-01

    Full Text Available Abstract Background Numerous pen devices are available to administer recombinant Human Growth Hormone (rhGH, and both patients and health plans have varying issues to consider when selecting a particular product and device for daily use. Therefore, the present study utilized multi-dimensional product analysis to assess potential time involvement, required weekly administration steps, and utilization costs relative to daily rhGH administration. Methods Study objectives were to conduct 1 Time-and-Motion (TM simulations in a randomized block design that allowed time and steps comparisons related to rhGH preparation, administration and storage, and 2 a Cost Minimization Analysis (CMA relative to opportunity and supply costs. Nurses naïve to rhGH administration and devices were recruited to evaluate four rhGH pen devices (2 in liquid form, 2 requiring reconstitution via TM simulations. Five videotaped and timed trials for each product were evaluated based on: 1 Learning (initial use instructions, 2 Preparation (arrange device for use, 3 Administration (actual simulation manikin injection, and 4 Storage (maintain product viability between doses, in addition to assessment of steps required for weekly use. The CMA applied micro-costing techniques related to opportunity costs for caregivers (categorized as wages, non-drug medical supplies, and drug product costs. Results Norditropin® NordiFlex and Norditropin® NordiPen (NNF and NNP, Novo Nordisk, Inc., Bagsværd, Denmark took less weekly Total Time (p ® Pen (GTP, Pfizer, Inc, New York, New York or HumatroPen® (HTP, Eli Lilly and Company, Indianapolis, Indiana. Time savings were directly related to differences in new package Preparation times (NNF (1.35 minutes, NNP (2.48 minutes GTP (4.11 minutes, HTP (8.64 minutes, p Conclusions Time-and-motion simulation data used to support a micro-cost analysis demonstrated that the pen device with the greater time demand has highest net costs.

  1. Efficiency and concordance of alternative methods for minimizing opportunity costs in conservation planning.

    Science.gov (United States)

    Cameron, Susan E; Williams, Kristen J; Mitchell, David K

    2008-08-01

    Scarce resources and competing land-use goals necessitate efficient biodiversity conservation. Combining multicriteria analysis with conservation decision-support tools improves efficiency of conservation planning by maximizing outcomes for biodiversity while minimizing opportunity costs to society. An opportunity cost is the benefit that could have been received by taking an alternative course of action (i.e., costs to society of protecting an area for biodiversity rather than developing it for some other use). Although different ways of integrating multiple opportunity costs into conservation planning have been suggested, there have been no tests as to which method is most efficient. We compared the relative efficiency of 3 such procedures(Faith & Walker [1996], Sarkar et al. [2004], and a procedure of our own design) in a systematic conservation-planning framework for the Milne Bay Province of Papua New Guinea. We devised 14 opportunity costs and assigned these to 3 scenarios representing different conservation planning concerns: food security, macro-economic development, and biodiversity persistence. For each scenario, we compared the efficiency of the 3 methods in terms of amount of biodiversity protected relative to total expenditure for each opportunity cost. All 3 methods captured similar amounts of biodiversity, but differed in total cost. Our method had the least overall cost and was therefore most efficient. Nevertheless, there was a high correlation and geographical concordance among all 3 methods, indicating a high degree of spatial overlap. This suggests that choosing an appropriate approach may often depend on contextual factors related to the design of the planning question, rather than efficiency alone. PMID:18637906

  2. SEQUENCING DELIVERIES TO MINIMIZE INVENTORY HOLDING COST WITH DOMINANT UPSTREAM SUPPLY CHAIN PARTNER

    Institute of Scientific and Technical Information of China (English)

    Sushil GUPTA; Manoj VANAJAKUMARI; Chelliah SRISKANDARAJAH

    2009-01-01

    This paper studies a two stage supply chain with a dominant upstream partner. Manufacturer is the dominant partner and operates in a Just-in-Time environment. Production is done in a single manufacturing line capable of producing two products without stopping the production for switching from one product to the other. The manufacturer imposes constraints on the distributor by adhering to his favorable production schedule which minimizes his manufacturing cost. Distributor on the other hand caters to retailers' orders without incurring any shortages and is responsible for managing the inventory of finished goods. Adhering to manufacturer's schedule may lead to high inventory carrying costs for the distributor. Distributor's problem, which is to find an optimal distribution sequence which minimizes the distributor's inventory cost under the constraint imposed by the manufacturer is proved NP-Hard by Manoj et al. (2008). Therefore, solving large size problems require efficient heuristics. We develop algorithms for the distribution problem by exploiting its structural properties. We propose two heuristics and use their solutions in the initial population of a genetic algorithm to arrive at solutions with an average deviation of less than 3.5% from the optimal solution for practical size problems.

  3. An Efficiency Improved Active Power Decoupling Circuit with Minimized Implementation Cost

    DEFF Research Database (Denmark)

    Tang, Yi; Blaabjerg, Frede

    2014-01-01

    Active power decoupling techniques are promising solutions for capacitance reduction in single-phase AC/DC or DC/AC systems. This paper proposes a novel circuit topology which can realize the power decoupling function without adding additional active switches into the circuit. Also, the proposed...... topology does not require additional passive component, e.g. inductors or film capacitors for ripple energy storage because this task can be accomplished by the dc-link capacitors themselves, and therefore its implementation cost can be minimized. Another unique feature of the proposed topology...

  4. Systematic process synthesis and design methods for cost effective waste minimization

    Energy Technology Data Exchange (ETDEWEB)

    Biegler, L.T.; Grossman, I.E.; Westerberg, A.W. [Carnegie Mellon Univ., Pittsburgh, PA (United States)

    1995-12-31

    We present progress on our work to develop synthesis methods to aid in the design of cost effective approaches to waste minimization. Work continues to combine the approaches of Douglas and coworkers and of Grossmann and coworkers on a hierarchical approach where bounding information allows it to fit within a mixed integer programming approach. We continue work on the synthesis of reactors and of flexible separation processes. In the first instance, we strive for methods we can use to reduce the production of potential pollutants, while in the second we look for ways to recover and recycle solvents.

  5. Minim typing--a rapid and low cost MLST based typing tool for Klebsiella pneumoniae.

    Directory of Open Access Journals (Sweden)

    Patiyan Andersson

    Full Text Available Here we report a single nucleotide polymorphism (SNP based genotyping method for Klebsiella pneumoniae utilising high-resolution melting (HRM analysis of fragments within the multilocus sequence typing (MLST loci. The approach is termed mini-MLST or Minim typing and it has previously been applied to Streptococcus pyogenes, Staphylococcus aureus and Enterococcus faecium. Six SNPs were derived from concatenated MLST sequences on the basis of maximisation of the Simpsons Index of Diversity (D. DNA fragments incorporating these SNPs and predicted to be suitable for HRM analysis were designed. Using the assumption that HRM alleles are defined by G+C content, Minim typing using six fragments was predicted to provide a D = 0.979 against known STs. The method was tested against 202 K. pneumoniae using a blinded approach in which the MLST analyses were performed after the HRM analyses. The HRM-based alleles were indeed in accordance with G+C content, and the Minim typing identified known STs and flagged new STs. The tonB MLST locus was determined to be very diverse, and the two Minim fragments located herein contribute greatly to the resolving power. However these fragments are refractory to amplification in a minority of isolates. Therefore, we assessed the performance of two additional formats: one using only the four fragments located outside the tonB gene (D = 0.929, and the other using HRM data from these four fragments in conjunction with sequencing of the tonB MLST fragment (D = 0.995. The HRM assays were developed on the Rotorgene 6000, and the method was shown to also be robust on the LightCycler 480, allowing a 384-well high through-put format. The assay provides rapid, robust and low-cost typing with fully portable results that can directly be related to current MLST data. Minim typing in combination with molecular screening for antibiotic resistance markers can be a powerful surveillance tool kit.

  6. Heuristic algorithm for RCPSP with the objective of minimizing activities' cost

    Institute of Scientific and Technical Information of China (English)

    Liu Zhenyuan; Wang Hongwei

    2006-01-01

    Resource-constrained project scheduling problem(RCPSP) is an important problem in research on project management. But there has been little attention paid to the objective of minimizing activities' cost with the resource constraints that is a critical sub-problem in partner selection of construction supply chain management because the capacities of the renewable resources supplied by the partners will effect on the project scheduling. Its mathematic model is presented firstly, and analysis on the characteristic of the problem shows that the objective function is non-regular and the problem is NP-complete following which the basic idea for solution is clarified. Based on a definition of preposing activity cost matrix, a heuristic algorithm is brought forward. Analyses on the complexity of the heuristics and the result of numerical studies show that the heuristic algorithm is feasible and relatively effective.

  7. Learning control for minimizing a quadratic cost during repetitions of a task

    Science.gov (United States)

    Longman, Richard W.; Chang, Chi-Kuang

    1990-01-01

    In many applications, control systems are asked to perform the same task repeatedly. Learning control laws have been developed over the last few years that allow the controller to improve its performance each repetition, and to converge to zero error in tracking a desired trajectory. This paper generates a new type of learning control law that learns to minimize a quadratic cost function for tracking. Besides being of interest in its own right, this objective alleviates the need to specify a desired trajectory that can actually be performed by the system. The approach used here is to adapt appropriate methods from numerical optimization theory in order to produce learning control algorithms that adjust the system command from repetition to repetition in order to converge to the quadratic cost optimal trajectory.

  8. Minimizing shell-and-tube heat exchanger cost with genetic algorithms and considering maintenance

    Energy Technology Data Exchange (ETDEWEB)

    Wildi-Tremblay, P.; Gosselin, L. [Universite Laval, Quebec (Canada). Dept. de genie mecanique

    2007-07-15

    This paper presents a procedure for minimizing the cost of a shell-and-tube heat exchanger based on genetic algorithms (GA). The global cost includes the operating cost (pumping power) and the initial cost expressed in terms of annuities. Eleven design variables associated with shell-and-tube heat exchanger geometries are considered: tube pitch, tube layout patterns, number of tube passes, baffle spacing at the centre, baffle spacing at the inlet and outlet, baffle cut, tube-to-baffle diametrical clearance, shell-to-baffle diametrical clearance, tube bundle outer diameter, shell diameter, and tube outer diameter. Evaluations of the heat exchangers performances are based on an adapted version of the Bell-Delaware method. Pressure drops constraints are included in the procedure. Reliability and maintenance due to fouling are taken into account by restraining the coefficient of increase of surface into a given interval. Two case studies are presented. Results show that the procedure can properly and rapidly identify the optimal design for a specified heat transfer process. (author)

  9. Study on a multi-brand auto distribution network serving multiple cities to minimize the total distribution cost

    OpenAIRE

    Balaña Pedrol, Elena

    2013-01-01

    The current research project consists of minimizing the total cost of an auto dealership supply chain management system that provides two auto brands for five major industrial cities in the Great Lake Area of the United States. The two auto brands are Ford and Chrysler. The five major cities are Chicago, Detroit, Indianapolis, St. Louis, and Cincinnati. The total cost includes transportation cost from auto assembly plants to individual cities, along with warehouse cost and/or transshipment co...

  10. AUTOMATIC WEB SERVICE SELECTION BY OPTIMIZING COST OF COMPOSITION IN SLAKY COMPOSER USING ASSIGNMENT MINIMIZATION APPROACH

    Directory of Open Access Journals (Sweden)

    P. Sandhya

    2012-12-01

    Full Text Available Web service composition is a means of building enterprises virtually by knitting relevant web services on the fly. Automatic web service composition is done dynamically at runtime. Extensive research has been done in the field of automatic web service composition. However all the works focus on providing client oriented results and hence there is less industry adoption of composition technology. In this paper we have proposed a new service collaboration stack that composes with realistic business metrics of a provider in addition to client metrics. Some of the service provider metrics include time planning, profit management, native intelligence, user adoption, environment, market scenario, vision and industry adoption. In this paper we focus on enhancing industry adoption through optimizing cost of service composition. We propose the SLAKY composer that solves assignment of appropriate service during composition as an assignment minimization problem to reduce the cost of composition. We also extend OWL-S profile sub ontology to augment cost as a service parameter.

  11. New method to minimize the preventive maintenance cost of series-parallel systems

    International Nuclear Information System (INIS)

    General preventive maintenance model for input components of a system, which improves the reliability to 'as good as new,' was used to optimize the maintenance cost. The cost function of a maintenance policy was minimized under given availability constraint. An algorithm for first inspection vector of times was described and used on selected system example. A special ratio-criterion, based on the time dependent Birnbaum importance factor, was used to generate the ordered sequence of first inspection times. Basic system availability calculations of the paper were done by using simulation approach with parallel simulation algorithm for availability analysis. These calculations, based on direct Monte Carlo technique, were applied within the programming tool Matlab. A genetic algorithm optimization technique was used and briefly described to create the Matlab's algorithm to solve the problem of finding the best maintenance policy with a given restriction. Adjacent problem, which we called 'reliability assurance,' was also theoretically solved, concerning the increase of the cost when asymptotic availability value conforms to a given availability constraint

  12. Minimization of Illness Absenteeism in Primary School Students Using Low-Cost Hygiene Interventions

    Directory of Open Access Journals (Sweden)

    Tambekar DH

    2012-07-01

    Full Text Available Objective: Safe water and hygiene intervention was evaluated to assess its impact on students’ health, hygiene practices and reduction in illness absenteeism in primary school students. Method: After evaluatingprimary schools of Amravati district; 50 students with high enteric illness absenteeism were selected for study. Families with problem of in-house water contamination were provided earthen pot with tap for water storage and soap for hand washing at school and home. Household drinking waters (before and after intervention were analyzed for potability. Results: By adopting correct water storage (water container with tap, handling and hand washing practices found to improve health and reduction in 20% illness absenteeism in school. Promoting these interventions and improvement in water-behavioral practices prevented in-house-water contamination. Conclusion: These low cost intervention (water storage container with tap promises to reducing school absenteeism by minimizing risk of transmission of enteric infections by promoting water and student hygiene.

  13. The analytic solution of the firm's cost-minimization problem with box constraints and the Cobb-Douglas model

    Science.gov (United States)

    Bayón, L.; Grau, J. M.; Ruiz, M. M.; Suárez, P. M.

    2012-12-01

    One of the most well-known problems in the field of Microeconomics is the Firm's Cost-Minimization Problem. In this paper we establish the analytical expression for the cost function using the Cobb-Douglas model and considering maximum constraints for the inputs. Moreover we prove that it belongs to the class C1.

  14. Current Status of Minimally Invasive Surgery for Renal Cell Carcinoma.

    Science.gov (United States)

    Smith, Zachary L

    2016-06-01

    Over the last three decades, the incidence of renal cell carcinoma (RCC) has continuously risen, generally attributed to the increased use of cross-sectional imaging across all medical disciplines. Fortunately, despite this rising incidence, the estimated 5-year relative survival rate has improved. This survival improvement likely parallels the stage migration of the last two decades toward an increased incidence of small renal masses (SRMs). However, this survival improvement may be secondary to improved surgical techniques and medical therapies for these malignancies. The increased incidence of SRMs has led to an expected evolution in the treatment of RCC. Minimally invasive surgical applications for the treatment of RCC have gained widespread popularity, and now these approaches to renal malignancies have surpassed open techniques in frequency of utilization. Laparoscopic and robotic-assisted techniques have now been applied to both radical and partial nephrectomy procedures of varying complexity. Additionally, percutaneous ablative procedures have been applied to the treatment of some SRMs, increasing the urologist's armamentarium further. Below, we provide a review of these minimally invasive surgical (MIS) procedures for the treatment of RCC. PMID:27021911

  15. Measures for minimizing residual operating costs and simultaneous optimization of the dismantling strategy

    International Nuclear Information System (INIS)

    The end of power operation of a nuclear power plant is followed either by safe enclosure and later demolition, or immediate dismantling and demolition. In the latter case, measures should be taken at the onset of the decommissioning phase to minimize the costs of operation of the infrastructure required during the disassembly phase (residual operation), thus allowing speedy disassembly over large areas of systems and components no longer required. Once a nuclear power plant has been decommissioned, the main systems determining costs of residual operation are those auxiliary systems whose economic performance had been of secondary importance during power operation, such as auxiliary cooling water, auxiliary steam, demineralized water supply, waste water treatment, ventilation, heating, air conditioning, etc. They are vastly overdimensioned for the requirements of residual operation, and even when the often highly diversified systems have been trimmed down, many pipe systems are bound to remain in operation in many parts of the building which upset the dismantling process. The case of the decommissioned Muelheim-Kaerlich nuclear power station now being dismantled is used to show that often it is not conversion and downsizing of former plant operation systems which constitute the best solution in terms of overall economics, but rather the installation, at an early point in time, of new systems and components adapted to the requirements of demolition and representing the current state of the art. (orig.)

  16. Cloud Computing-An Ultimate Technique to Minimize Computing cost for Developing Countries

    Directory of Open Access Journals (Sweden)

    Narendra Kumar

    2012-03-01

    Full Text Available The presented paper deals with how remotely managed computing and IT resources can be beneficial in the developing countries like India and Asian sub-continent countries. This paper not only defines the architectures and functionalities of cloud computing but also indicates strongly about the current demand of Cloud computing to achieve organizational and personal level of IT supports in very minimal cost with high class flexibility. The power of cloud can be used to reduce the cost of IT - resources and infrastructure with minimum risk and great efficiency.Cloud computing can be used to host a variety of applications such as vast and complicated business applications, enterprise database, e-commerce applications, payment gateway, software development and testing tools, on-demand applications and many more. Cloud computing enables organizations to increase hardware utilization rates tremendously, and to scale up the business needs instantly, without having to invest in new infrastructure, train new personnel, or license new software products. It also creates several new classes of opportunities to develop a cost effective generation of network services, in a very less amount of time and for less money. Minimization of cost is the prime need of any developing country and the cloud computing provides a full proof way to run on the cheapest technology ever developed. The cloud computing brings a new level of efficiency and economy to deliver Information Technology Resources (ITR on demand, and in the process it opens new business models, creates new icons to work, creates new business opportunities and open up entire new face of Information Technology in a secure and cost effective environment.There are several ranges of cloud computing implementations. Cloud computing may be implemented by service providers, that is, Public clouds or in enterprise datacenters, that is, private cloud that allocate a large number of resources and capabilities so

  17. Cost targets for domestic fuel cell CHP

    Science.gov (United States)

    Staffell, I.; Green, R.; Kendall, K.

    Fuel cells have the potential to reduce domestic energy bills by providing both heat and power at the point of use, generating high value electricity from a low cost fuel. However, the cost of installing the fuel cell must be sufficiently low to be recovered by the savings made over its lifetime. A computer simulation is used to estimate the savings and cost targets for fuel cell CHP systems. Two pitfalls of this kind of simulation are addressed: the selection of representative performance figures for fuel cells, and the range of houses from which energy demand data was taken. A meta-study of the current state of the art is presented, and used with 102 house-years of demand to simulate the range of economic performance expected from four fuel cell technologies within the UK domestic CHP market. Annual savings relative to a condensing boiler are estimated at €170-300 for a 1 kWe fuel cell, giving a target cost of €350-625 kW -1 for any fuel cell technology that can demonstrate a 2.5-year lifetime. Increasing lifetime and reducing fuel cell capacity are identified as routes to accelerated market entry. The importance of energy demand is seen to outweigh both economic and technical performance assumptions, while manufacture cost and system lifetime are highlighted as the only significant differences between the technologies considered. SOFC are considered to have the greatest potential, but uncertainty in the assumptions used precludes any clear-cut judgement.

  18. Operation cost minimization of droop-controlled DC microgrids based on real-time pricing and optimal power flow

    OpenAIRE

    Li, Chendan; de Bosio, Federico; Chaudhary, Sanjay Kumar; Graells, Moises; Quintero, Juan Carlos Vasquez; Guerrero, Josep M.

    2015-01-01

    In this paper, an optimal power flow problem is formulated in order to minimize the total operation cost by considering real-time pricing in DC microgrids. Each generation resource in the system, including the utility grid, is modeled in terms of operation cost, which combines the cost-efficiency of the system with the demand response requirements of the utility. By considering the primary (local) control of the grid-forming converters of a microgrid, optimal parameters can be directly applie...

  19. Minimal doses of hydroxyurea for sickle cell disease

    Directory of Open Access Journals (Sweden)

    C.S.P. Lima

    1997-08-01

    Full Text Available The use of hydroxyurea (HU can improve the clinical course of sickle cell disease. However, several features of HU treatment remain unclear, including the predictability of drug response and determination of adequate doses, considering positive responses and minimal side effects. In order to identify adequate doses of HU for treatment of sickle cell disease, 10 patients, 8 with sickle cell anemia and 2 with Sß thalassemia (8SS, 2Sß, were studied for a period of 6 to 19 months in an open label dose escalation trial (10 to 20 mg kg-1 day-1. Hemoglobin (Hb, fetal hemoglobin (Hb F and mean corpuscular volume (MCV values and reticulocyte, neutrophil and platelet counts were performed every two weeks during the increase of the HU dose and every 4 weeks when the maximum HU dose was established. Reduction in the number of vasoocclusive episodes was also considered in order to evaluate the efficiency of the treatment. The final Hb and Hb F concentrations, and MCV values were significantly higher than the initial values, while the final reticulocyte and neutrophil counts were significantly lower. There was an improvement in the concentration of Hb (range: 0.7-2.0 g/dl at 15 mg HU kg-1 day-1, but this concentration did not increase significantly when the HU dose was raised to 20 mg kg-1 day-1. The concentration of Hb F increased significantly (range: 1.0-18.1% when 15 mg HU was used, and continued to increase when the dose was raised to 20 mg kg-1 day-1. The final MCV values increased 11-28 fl (femtoliters. However, reticulocyte (range: 51-205 x 109/l and neutrophil counts (range: 9.5-1.3 x 109/l obtained at this dose were significantly lower than those obtained with 15 mg kg-1 day-1. All patients reported a decrease in frequency or severity of vasoocclusive episodes. These results suggest that a hydroxyurea dose of 15 mg kg-1 day-1 seems to be adequate for treatment of sickle cell disease in view of the minimal side effects observed and the improvement

  20. Cost-minimized combinations of wind power, solar power and electrochemical storage, powering the grid up to 99.9% of the time

    OpenAIRE

    Budischak, Cory; Sewell, DeAnna; Thomson, Heather; Mach, Leon; Veron, Dana E.; Kempton, Willett

    2013-01-01

    We model many combinations of renewable electricity sources (inland wind, offshore wind, and photovoltaics) with electrochemical storage (batteries and fuel cells), incorporated into a large grid system (72 GW). The purpose is twofold: 1) although a single renewable generator at one site produces intermittent power, we seek combinations of diverse renewables at diverse sites, with storage, that are not intermittent and satisfy need a given fraction of hours. And 2) we seek minimal cost, calcu...

  1. Targeting therapy to minimize antimicrobial use in preweaned calves: effects on health, growth, and treatment costs.

    Science.gov (United States)

    Berge, A C B; Moore, D A; Besser, T E; Sischo, W M

    2009-09-01

    Prophylactic and therapeutic antimicrobial use in food animals is questioned because of the potential for development of resistant bacteria and future inability to use some antimicrobials for human or animal disease. The objectives of this study were to determine the effect of raising preweaned dairy calves without antimicrobials in the milk and minimizing therapeutic antimicrobial treatment on morbidity, mortality, weight gain, and treatment costs. Newborn calves (n = 358) were allocated to 1 of 4 groups, housed outdoors in individual hutches, and monitored for 28 d. Calves in the conventional therapy (CT) group were treated as per dairy protocol with sulfamethoxazole/trimethoprim, spectinomycin, penicillin, and bismuth-pectin for diarrhea. The targeted therapy (TT) group included bismuth-pectin for diarrhea and antimicrobial treatment only in cases of fever or depressed attitude. Within CT and TT groups, calves were equally assigned to receive neomycin and tetracycline in their milk for the first 2 wk of life (AB-milk) or no antimicrobials (NoAB-milk). Daily health evaluations included fecal consistency, respiratory disease, attitude, and hydration status as well as milk and grain consumption. A negative binomial model evaluated the total number of days with diarrhea days in each group. General linear models were used to assess average daily weight gain and grain consumption. Conventionally treated calves had 70% more days with diarrhea than TT calves, and AB-milk calves had 31% more days with diarrhea compared with NoAB-milk calves. The TT calves tended to have a higher average daily gain by 28 d and consumed more grain compared with CT calves. If antimicrobials were used only for diarrhea cases with fever, inappetence, or depression and no in-milk antimicrobials were used, a $10 per calf savings could be realized. Targeting antimicrobial therapy of calf diarrhea cases is prudent not only to save the drugs for future use but also to prevent the potential for

  2. Active Hedging Greeks of an Options Portfolio integrating churning and minimization of cost of hedging using Quadratic & Linear Programing

    OpenAIRE

    Sinha, Pankaj; Gupta, Akshay; Mudgal, Hemant

    2010-01-01

    This paper proposes a methodology for active hedging Greeks of an option portfolio integrating churning and minimization of cost of hedging. In the first section, hedging strategy is implemented by taking positions in other available options, while simultaneously minimizing the net premium paid for the hedging and then churning the portfolio to take into account the changed value of Greeks in the new portfolio. In the second section, the paper extends the model to incorporate the transaction ...

  3. Cost minimizing of cutting process for CNC thermal and water-jet machines

    Science.gov (United States)

    Tavaeva, Anastasia; Kurennov, Dmitry

    2015-11-01

    This paper deals with optimization problem of cutting process for CNC thermal and water-jet machines. The accuracy of objective function parameters calculation for optimization problem is investigated. This paper shows that working tool path speed is not constant value. One depends on some parameters that are described in this paper. The relations of working tool path speed depending on the numbers of NC programs frames, length of straight cut, configuration part are presented. Based on received results the correction coefficients for working tool speed are defined. Additionally the optimization problem may be solved by using mathematical model. Model takes into account the additional restrictions of thermal cutting (choice of piercing and output tool point, precedence condition, thermal deformations). At the second part of paper the non-standard cutting techniques are considered. Ones may lead to minimizing of cutting cost and time compared with standard cutting techniques. This paper considers the effectiveness of non-standard cutting techniques application. At the end of the paper the future research works are indicated.

  4. Optimization of PHEV Power Split Gear Ratio to Minimize Fuel Consumption and Operation Cost

    Science.gov (United States)

    Li, Yanhe

    A Plug-in Hybrid Electric Vehicle (PHEV) is a vehicle powered by a combination of an internal combustion engine and an electric motor with a battery pack. The battery pack can be charged by plugging the vehicle to the electric grid and from using excess engine power. The research activity performed in this thesis focused on the development of an innovative optimization approach of PHEV Power Split Device (PSD) gear ratio with the aim to minimize the vehicle operation costs. Three research activity lines have been followed: • Activity 1: The PHEV control strategy optimization by using the Dynamic Programming (DP) and the development of PHEV rule-based control strategy based on the DP results. • Activity 2: The PHEV rule-based control strategy parameter optimization by using the Non-dominated Sorting Genetic Algorithm (NSGA-II). • Activity 3: The comprehensive analysis of the single mode PHEV architecture to offer the innovative approach to optimize the PHEV PSD gear ratio.

  5. Operation Cost Minimization of Droop-Controlled DC Microgrids Based on Real-Time Pricing and Optimal Power Flow

    DEFF Research Database (Denmark)

    Li, Chendan; de Bosio, Federico; Chaudhary, Sanjay Kumar;

    2015-01-01

    In this paper, an optimal power flow problem is formulated in order to minimize the total operation cost by considering real-time pricing in DC microgrids. Each generation resource in the system, including the utility grid, is modeled in terms of operation cost, which combines the cost...... optimization problem is solved in a heuristic way by using genetic algorithms. In order to test the proposed algorithm, a six-bus droop-controlled DC microgrid is used as a case-study. The obtained simulation results show that under variable renewable generation, load, and electricity prices, the proposed...... method can successfully dispatch the resources in the microgrid with lower total operation costs....

  6. A Model of Emission Trading for Minimizing the Cost of Air Pollution Control from Belgian Power Plants

    OpenAIRE

    Hecq, Walter; Kestemont, Bruno

    1991-01-01

    In Belgium recent national and community legislation regulates emission levels of "acid pollutants" (SO2, NOx) and apply to large combustion facilities whose pollutants are transported over large distances. Complying with these legislations requires costly emission control equipment. In order to minimize the costs of clean-up operations, this paper analyses the potentialities of an emission trading programme by means of a linear programming model. Six retrofit power plants have been chosen to...

  7. Cost-effectiveness of opportunistic screening and minimal contact psychotherapy to prevent depression in primary care patients

    OpenAIRE

    Berg, Merlijn; Smit, Filip; Vos, Theo; van Baal, Pieter

    2011-01-01

    textabstractBackground: Depression causes a large burden of disease worldwide. Effective prevention has the potential to reduce that burden considerably. This study aimed to investigate the cost-effectiveness of minimal contact psychotherapy, based on Lewinsohn's 'Coping with depression' course, targeted at opportunistically screened individuals with sub-threshold depression. Methods and Results: Using a Markov model, future health effects and costs of an intervention scenario and a current p...

  8. Minimizing the energy requirement of dewatering scenedesmus sp. by microfiltration: performance, costs, and feasibility.

    Science.gov (United States)

    Gerardo, Michael L; Oatley-Radcliffe, Darren L; Lovitt, Robert W

    2014-01-01

    The harvesting of the microalgae Scenedesmus species using a 200 L pilot-scale microfiltration system was investigated and critically assessed. The energy requirement was determined and correlated to the different operating parameters, such as transmembrane pressure (ΔP), membrane area, temperature, and initial biomass concentration. A filtration model was developed and showed a strong correlation with experimental data up to 20.0 g of dry cell weight (DCW)/L. The non-optimized filtration system had an energy requirement of 2.23 kWh/m(3) with an associated cost of $0.282/kg of microalgae. The investigation into the influence of the operating parameters and scale-up effects showed that the energy requirement could be substantially reduced to 0.90 kWh/m(3) and $0.058/kg of microalgae harvested. Maintenance costs associated with cleaning were estimated to be 0.23 kWh or $0.029/batch of microalgae processed. Dependent upon the operating conditions, harvesting may represent 6-45% of the energy embedded in the microalgae with a carbon footprint of 0.74-1.67 kg of CO2/kg of microalgae. Microfiltration was demonstrated to be a feasible microalgae harvesting technology allowing for more than 99% volume reduction. The energy requirement and associated carbon footprint of microalgae harvesting reported here do not forfeit the need for an industrial-scale study; however, the information provided presents a more realistic approximation than the literature reported to date. PMID:24341825

  9. Precision Feeding in Dairy Ration Cost Minimization Under Producer's Risk Management

    OpenAIRE

    Salim, Juma K.; Dillon, Carl R.

    2007-01-01

    The biophysical simulation data from Cornell Net Carbohydrate and Protein System were used in non-linear programming model for least cost ration incorporating ingredient nutrient and price variations. Precision feeding practice indicated to have lower mean cost ration than whole herd feeding in terms of ration cost.

  10. Multiagent based Distributed Control for Operation Cost Minimization of Droop Controlled AC Microgrid Using Incremental Cost Consensus

    OpenAIRE

    Li, Chendan; Firoozabadi, Mehdi Savaghebi; Quintero, Juan Carlos Vasquez; Guerrero, Josep M.

    2015-01-01

    Microgrid, as a promising technology to integrate renewable energy resources in the distribution system, is gaining increasing research interests recently. Although many previous works have been done based on the droop control in a microgrid, they mainly focus on achieving proportional power sharing based on the power rating. With various types of distributed generator (DG) units in the system, factors that closely related to the operation cost, such as fuel cost and efficiencies of the gener...

  11. The Right Choice for Production Patterns to Minimize Cost of Incremental

    Directory of Open Access Journals (Sweden)

    Erick Wijaya

    2011-04-01

    of 3,330,267,500 IDR. For Constant production patterns can lead to costs amounting to 3,696,317,500 IDR whereas if the company uses pattern Moderate production costs to be incurred amounted to 3,289,417,500 IDR. From the results of this study showed that moderate production patterns have the smallest Incremental costs compared to the wavy or constant patterns of production.

  12. A minimal cost micropropagation protocol for Dianthus caryophyllus L.-- a commercially significant venture.

    Science.gov (United States)

    Pant, Manu

    2016-03-01

    In tissue culture, high production cost of the products restricts their reach. Though tissue culture is a major strength in floriculture it is marred by pricing issues. Hence, we developed a complete regeneration low cost micropropagation protocol for an economically important floriculture crop, carnation (Dianthus caryophyllus L.). Successful regeneration of carnation from nodal explants on cost-efficient medium indicates that psyllium husk, sugar and RO water can effectively replace the conventional medium comprising agar, sucrose and distilled water. The protocol can contribute to increased carnation production at comparatively reduced cost, and there by encourage wide scale adoption by the common growers. PMID:27145634

  13. A variation reduction allocation model for quality improvement to minimize investment and quality costs by considering suppliers’ learning curve

    Science.gov (United States)

    Rosyidi, C. N.; Jauhari, WA; Suhardi, B.; Hamada, K.

    2016-02-01

    Quality improvement must be performed in a company to maintain its product competitiveness in the market. The goal of such improvement is to increase the customer satisfaction and the profitability of the company. In current practice, a company needs several suppliers to provide the components in assembly process of a final product. Hence quality improvement of the final product must involve the suppliers. In this paper, an optimization model to allocate the variance reduction is developed. Variation reduction is an important term in quality improvement for both manufacturer and suppliers. To improve suppliers’ components quality, the manufacturer must invest an amount of their financial resources in learning process of the suppliers. The objective function of the model is to minimize the total cost consists of investment cost, and quality costs for both internal and external quality costs. The Learning curve will determine how the employee of the suppliers will respond to the learning processes in reducing the variance of the component.

  14. Optimizing diagnostic workup in the DRG environment: Dynamic algorithms and minimizing radiologic costs may cost your hospital money

    International Nuclear Information System (INIS)

    In certain diagnosis-related group (DRG) categories, the availability of sufficient CT scanners or of new equipment, such as MR equipment, can expedite the definitive workup. This will reduce the average length of stay and hospital cost. We analyzed the total hospital and radiologic charges by DRG category for all patients admitted to our hospital in 1985 and 1986. Although the cost per procedure is relatively high, the radiologic component is a small percentage of total hospital costs (median, 3%; maximum, <10%). The authors developed alternative diagnostic algorithms for radiologic-intensive DRG categories. Different diagnostic algorithms proposed for the same clinical problems were compared analytically in terms of impact on the hospital (cost, equipment availability, and length of stay). An example is the workup for FUO. Traditional approach uses plain x-rays and gallium scans and only uses CT when localizing symptoms are present. An alternative approach is to perform CT only. Although more CT examinations would be required, there is considerable reduction in the length of hospital stay and in overall charges. Neurologic and thoracic workups will be given as examples of classes or problems that can be addressed analytically: sequencing of the workup; prevalence; patient population; resource of allocation; and introduction of new imaging modality

  15. WESF hot cells waste minimization criteria hot cells window seals evaluation

    International Nuclear Information System (INIS)

    WESF will decouple from B Plant in the near future. WESF is attempting to minimize the contaminated solid waste in their hot cells and utilize B Plant to receive the waste before decoupling. WESF wishes to determine the minimum amount of contaminated waste that must be removed in order to allow minimum maintenance of the hot cells when they are placed in ''laid-up'' configuration. The remaining waste should not cause unacceptable window seal deterioration for the remaining life of the hot cells. This report investigates and analyzes the seal conditions and hot cell history and concludes that WESF should remove existing point sources, replace cerium window seals in F-Cell and refurbish all leaded windows (except for A-Cell). Work should be accomplished as soon as possible and at least within the next three years

  16. Waste Minimization Improvements Achieved Through Six Sigma Analysis Result In Significant Cost Savings

    International Nuclear Information System (INIS)

    Improved waste minimization practices at the Department of Energy's (DOE) Idaho National Engineering and Environmental Laboratory (INEEL) are leading to a 15% reduction in the generation of hazardous and radioactive waste. Bechtel, BWXT Idaho, LLC (BBWI), the prime management and operations contractor at the INEEL, applied the Six Sigma improvement process to the INEEL Waste Minimization Program to review existing processes and define opportunities for improvement. Our Six Sigma analysis team: composed of an executive champion, process owner, a black belt and yellow belt, and technical and business team members used this statistical based process approach to analyze work processes and produced ten recommendations for improvement. Recommendations ranged from waste generator financial accountability for newly generated waste to enhanced employee recognition programs for waste minimization efforts. These improvements have now been implemented to reduce waste generation rates and are producing positive results

  17. A Stochastic Integer Programming Model for Minimizing Cost in the Use of Rain Water Collectors for Firefighting

    Directory of Open Access Journals (Sweden)

    Luis A. Rivera-Morales

    2014-01-01

    Full Text Available In this paper we propose a stochastic integer programming optimization model to determine the optimal location and number of rain water collectors (RWCs for forest firefighting. The objective is to minimize expected total cost to control forest fires. The model is tested using a real case and several additional realistic scenarios. The impact on the solution of varying the limit on the number of RWCs, the RWC water capacity, the aircraft capacity, the water demands, and the aircraft operating cost is explored. Some observations are that the objective value improves with larger RWCs and with the use of aircraft with greater capacity.

  18. New methods to minimize the preventive maintenance cost of series-parallel systems using ant colony optimization

    International Nuclear Information System (INIS)

    This article is based on a previous study made by Bris, Chatelet and Yalaoui [Bris R, Chatelet E, Yalaoui F. New method to minimise the preventive maintenance cost of series-parallel systems. Reliab Eng Syst Saf 2003;82:247-55]. They use genetic algorithm to minimize preventive maintenance cost problem for the series-parallel systems. We propose to improve their results developing a new method based on another technique, the Ant Colony Optimization (ACO). The resolution consists in determining the solution vector of system component inspection periods, T P. Those calculations were applied within the programming tool Matlab. Thus, highly interesting results and improvements of previous studies were obtained

  19. Green Energy in New Construction: Maximize Energy Savings and Minimize Cost

    Science.gov (United States)

    Ventresca, Joseph

    2010-01-01

    People often use the term "green energy" to refer to alternative energy technologies. But green energy doesn't guarantee maximum energy savings at a minimum cost--a common misconception. For school business officials, green energy means getting the lowest energy bills for the lowest construction cost, which translates into maximizing green energy…

  20. Implementation of Rapid Prototyping Tools for Power Loss and Cost Minimization of DC-DC Converters

    Directory of Open Access Journals (Sweden)

    Amruta V. Kulkarni

    2016-07-01

    Full Text Available In this paper, power loss and cost models of power electronic converters based on converter ratings and datasheet information are presented. These models aid in creating rapid prototypes which facilitate the component selection process. Through rapid prototyping, users can estimate power loss and cost which are essential in design decisions. The proposed approach treats main power electronic components of a converter as building blocks that can be arranged to obtain multiple topologies to facilitate rapid prototyping. In order to get system-level power loss and cost models, two processes are implemented. The first process automatically provides minimum power loss or cost estimates and identifies components for specific applications and ratings; the second process estimates power losses and costs of each component of interest as well as the whole system. Two examples are used to illustrate the proposed approaches—boost and buck converters in continuous conduction mode. Achieved cost and loss estimates are over 93% accurate when compared to measured losses and real cost data. This research presents derivations of the proposed models, experimental validation of the models and demonstration of a user friendly interface that integrates all the models. Tools presented in this paper are expected to be very useful for practicing engineers, designers, and researchers, and are flexible and adaptable with changing or new technologies and varying component prices.

  1. Cost-minimization analysis favours intravenous ferric carboxymaltose over ferric sucrose for the ambulatory treatment of severe iron deficiency.

    Directory of Open Access Journals (Sweden)

    Xavier Calvet

    Full Text Available OBJECTIVE: Intravenous iron is widely used to treat iron deficiency in day-care units. Ferric carboxymaltose (FCM allows administration of larger iron doses than iron sucrose (IS in each infusion (1000 mg vs. 200 mg. As FCM reduces the number of infusions required but is more expensive, we performed a cost-minimization analysis to compare the cost impact of the two drugs. MATERIALS AND METHODS: The number of infusions and the iron dose of 111 consecutive patients who received intravenous iron at a gastrointestinal diseases day-care unit from 8/2007 to 7/2008 were retrospectively obtained. Costs of intravenous iron drugs were obtained from the Spanish regulatory agencies. The accounting department of the Hospital determined hospital direct and indirect costs for outpatient iron infusion. Non-hospital direct costs were calculated on the basis of patient interviews. In the pharmacoeconomic model, base case mean costs per patient were calculated for administering 1000 mg of iron per infusion using FCM or 200 mg using IS. Sensitivity analysis and Monte Carlo simulation were performed. RESULTS: Under baseline assumptions, the estimated cost of iron infusion per patient and year was €304 for IS and €274 for FCM, a difference of €30 in favour of FCM. Adding non-hospital direct costs to the model increased the difference to €67 (€354 for IS vs. €287 for FCM. A Monte Carlo simulation taking into account non-hospital direct costs favoured the use of FCM in 97% of simulations. CONCLUSION: In this pharmacoeconomic analysis, FCM infusion reduced the costs of iron infusion at a gastrointestinal day-care unit.

  2. Minimally Machined HoneySiC Mirrors for Low Areal Cost and Density Project

    Data.gov (United States)

    National Aeronautics and Space Administration — A problem perceived for Trex Enterprises chemical vapor composite silicon carbide CVC SiCTM mirrors is the cost associated with machining and lightweighting the...

  3. Minimally Machined HoneySiC Mirrors for Low Areal Cost and Density Project

    Data.gov (United States)

    National Aeronautics and Space Administration — One of the major problems perceived for Trex Enterprises chemical vapor composite silicon carbide mirrors is the cost of machining, lightweighting and polishing the...

  4. A cost-minimization analysis of the angio-seal vascular closure device following percutaneous coronary intervention.

    Science.gov (United States)

    Resnic, Frederic S; Arora, Nipun; Matheny, Michael; Reynolds, Matthew R

    2007-03-15

    The Angio-Seal vascular closure device has been shown to be safe and effective in decreasing the time to hemostasis after percutaneous coronary intervention (PCI). The health economic implications of routinely using Angio-Seal after PCI have not been explored. We performed a cost-minimization analysis comparing routine Angio-Seal use after PCI with mechanical compression using a decision analytic model. The relative probabilities of 7 vascular access complications were derived from pooled analysis of published randomized trials. The incremental hospital cost of each vascular complication was estimated by a matched case-control analysis of 3,943 patients who underwent PCI at our center from January 2002 and December 2004. Appropriate sensitivity and uncertainty analyses were performed. After accounting for differences in expected rates of specific complications between the 2 strategies and the incremental costs of each vascular event, the routine use of Angio-Seal was associated with a lower cost per PCI procedure of 44 dollars. Probabilistic sensitivity analysis of all model assumptions using second-order Monte Carlo simulation confirmed the economic advantage of Angio-Seal in 74% of model replications. In conclusion, after PCI, the routine use of Angio-Seal for femoral vascular access management was associated with net cost savings compared with mechanical compression. This cost savings was in addition to the previously demonstrated advantages of Angio-Seal in terms of patient comfort and preference. PMID:17350361

  5. Wind turbine reliability : understanding and minimizing wind turbine operation and maintenance costs.

    Energy Technology Data Exchange (ETDEWEB)

    2004-11-01

    Wind turbine system reliability is a critical factor in the success of a wind energy project. Poor reliability directly affects both the project's revenue stream through increased operation and maintenance (O&M) costs and reduced availability to generate power due to turbine downtime. Indirectly, the acceptance of wind-generated power by the financial and developer communities as a viable enterprise is influenced by the risk associated with the capital equipment reliability; increased risk, or at least the perception of increased risk, is generally accompanied by increased financing fees or interest rates. Cost of energy (COE) is a key project evaluation metric, both in commercial applications and in the U.S. federal wind energy program. To reflect this commercial reality, the wind energy research community has adopted COE as a decision-making and technology evaluation metric. The COE metric accounts for the effects of reliability through levelized replacement cost and unscheduled maintenance cost parameters. However, unlike the other cost contributors, such as initial capital investment and scheduled maintenance and operating expenses, costs associated with component failures are necessarily speculative. They are based on assumptions about the reliability of components that in many cases have not been operated for a complete life cycle. Due to the logistical and practical difficulty of replacing major components in a wind turbine, unanticipated failures (especially serial failures) can have a large impact on the economics of a project. The uncertainty associated with long-term component reliability has direct bearing on the confidence level associated with COE projections. In addition, wind turbine technology is evolving. New materials and designs are being incorporated in contemporary wind turbines with the ultimate goal of reducing weight, controlling loads, and improving energy capture. While the goal of these innovations is reduction in the COE, there is

  6. Cost Minimization Analysis of Precut Cornea Grafts in Descemet Stripping Automated Endothelial Keratoplasty.

    Science.gov (United States)

    Yong, Kai-Ling; Nguyen, Hai V; Cajucom-Uy, Howard Y; Foo, Valencia; Tan, Donald; Finkelstein, Eric A; Mehta, Jodhbir S

    2016-02-01

    Descemet stripping automated endothelial keratoplasty (DSAEK) is the most common corneal transplant procedure. A key step in the procedure is preparing the donor cornea for transplantation. This can be accomplished via 1 of 3 alternatives: surgeon cuts the cornea on the day of surgery, the cornea is precut ahead of time in an offsite facility by a trained technician, or a precut cornea is purchased from an eye bank. Currently, there is little evidence on the costs and effectiveness of these 3 strategies to allow healthcare providers decide upon the preferred method to prepare grafts.The aim of this study was to compare the costs and relative effectiveness of each strategy.The Singapore National Eye Centre and Singapore Eye Bank performed both precut cornea and surgeon-cut cornea transplant services between 2009 and 2013.This study included 110 subjects who received precut cornea and 140 who received surgeon-cut cornea. Clinical outcomes and surgical duration were compared across the strategies using the propensity score matching. The cost of each strategy was estimated using the microcosting and consisted of facility costs and procedural costs including surgical duration. One-way sensitivity analysis and threshold analysis were performed.The cost for DSAEK was highest for the surgeon-cut approach ($13,965 per procedure), followed by purchasing precut corneas ($12,659) and then setting up precutting ($12,421). The higher procedural cost of the surgeon-cut approach was largely due to the longer duration of the procedure (surgeon-cut = 72.54 minutes, precut = 59.45 minutes, P cut. Threshold analysis demonstrated that if the number of cases was below 31 a year, the strategy that yielded the lowest cost was purchasing precut cornea from eye bank. If there were more than 290 cases annually, the cheapest option would be to setup precutting facility.Our findings suggest that it is more efficient for centers that are performing a large number of cornea

  7. Guidelines to Minimize the Cost of Software Quality in Agile Scrum Process

    OpenAIRE

    Deepa Vijay; Gopinath Ganapathy

    2014-01-01

    This paper presents a case study of Agile Scrum process followed in Retail Domain project. This paper also reveals the impacts of Cost of Software Quality, when agile scrum process is not followed efficiently. While analyzing the case study, the gaps were found and guidelines for process improvements were also suggested in this paper.

  8. Guidelines to minimize cost of software quality in agile scrum process

    OpenAIRE

    Vijay, Deepa; Ganapathy, Gopinath

    2014-01-01

    This paper presents a case study of Agile Scrum process followed in Retail Domain project. This paper also reveals the impacts of Cost of Software Quality, when agile scrum process is not followed efficiently. While analyzing the case study, the gaps were found and guidelines for process improvements were also suggested in this paper.

  9. Guidelines to Minimize the Cost of Software Quality in Agile Scrum Process

    Directory of Open Access Journals (Sweden)

    Deepa Vijay

    2014-06-01

    Full Text Available This paper presents a case study of Agile Scrum process followed in Retail Domain project. This paper also reveals the impacts of Cost of Software Quality, when agile scrum process is not followed efficiently. While analyzing the case study, the gaps were found and guidelines for process improvements were also suggested in this paper.

  10. Wind turbine reliability :understanding and minimizing wind turbine operation and maintenance costs.

    Energy Technology Data Exchange (ETDEWEB)

    Walford, Christopher A. (Global Energy Concepts. Kirkland, WA)

    2006-03-01

    Wind turbine system reliability is a critical factor in the success of a wind energy project. Poor reliability directly affects both the project's revenue stream through increased operation and maintenance (O&M) costs and reduced availability to generate power due to turbine downtime. Indirectly, the acceptance of wind-generated power by the financial and developer communities as a viable enterprise is influenced by the risk associated with the capital equipment reliability; increased risk, or at least the perception of increased risk, is generally accompanied by increased financing fees or interest rates. This paper outlines the issues relevant to wind turbine reliability for wind turbine power generation projects. The first sections describe the current state of the industry, identify the cost elements associated with wind farm O&M and availability and discuss the causes of uncertainty in estimating wind turbine component reliability. The latter sections discuss the means for reducing O&M costs and propose O&M related research and development efforts that could be pursued by the wind energy research community to reduce cost of energy.

  11. Cost-minimization analysis: radiation treatment with and without a multi-leaf collimator

    International Nuclear Information System (INIS)

    Purpose: To compare the costs of radiation treatment on a linear accelerator with a multileaf collimator (MLC) versus treatment on a linear accelerator without an MLC. The study was designed to determine whether the increased throughput of fields and decreased block cutting made the MLC cost effective from an institutional perspective. Methods and Materials: The number of fields, basic treatment equivalent, equivalent simple treatment visits, and blocks were prospectively collected for the four linear accelerators. Building, equipment, staffing, and service costs were all obtained in 1999 Australian dollars from the manufacturers and hospital department heads. The Joint Radiation Oncology Centre at Westmead and Nepean Hospitals, which are Australian public hospitals, runs as one unit, with the same staff, and currently operates five linear accelerators. Currently, four of the linear accelerators are used for general radiotherapy, operating for exactly the same hours; the final machine operates more limited hours and is used for specialized radiotherapy techniques and emergency cases. Results: The two machines with MLCs, on average, treated 5,169 fields each, while the two machines without MLCs treated 4,543 fields in a 3-month period, a 12% increase in throughput. The two non-MLC machines required 155 premounted trays (PMTs) in total, while the MLC machines required 17 PMTs. Linear accelerators with MLCs were demonstrably more efficient, and while their capital costs were higher, the reduction in labor costs associated with block cutting and, particularly the increased throughput, more than offset these initial costs. The total cost of a radiation field with an MLC was found to be $A101.69 compared to $A106.98 without an MLC. A multiway sensitivity analysis showed the results to be robust. The worst-case scenario was a departmental savings of $A168,000 per year; the best-case scenario was a savings of $A680,000 per year. Conclusion: Under the conditions pertaining

  12. Implementation and complexity of the watershed-from-markers algorithm computed as a minimal cost forest

    CERN Document Server

    Felkel, P; Wegenkittl, R; Felkel, Petr; Bruckwschwaiger, Mario; Wegenkittl, Rainer

    2001-01-01

    The watershed algorithm belongs to classical algorithms in mathematical morphology. Lotufo et al. published a principle of the watershed computation by means of an iterative forest transform (IFT), which computes a shortest path forest from given markers. The algorithm itself was described for a 2D case (image) without a detailed discussion of its computation and memory demands for real datasets. As IFT cleverly solves the problem of plateaus and as it gives precise results when thin objects have to be segmented, it is obvious to use this algorithm for 3D datasets taking in mind the minimizing of a higher memory consumption for the 3D case without loosing low asymptotical time complexity of O(m+C) (and also the real computation speed). The main goal of this paper is an implementation of the IFT algorithm with a priority queue with buckets and careful tuning of this implementation to reach as minimal memory consumption as possible. The paper presents five possible modifications and methods of implementation of...

  13. Production and delivery batch scheduling with a common due date and multiple vehicles to minimize total cost

    Science.gov (United States)

    Prasetyaningsih, E.; Suprayogi; Samadhi, TMAA; Halim, AH

    2016-02-01

    This paper studies production and delivery batch scheduling problems for a single- supplier-to-a-single-manufacturer case, with multiple capacitated vehicles wherein different holding costs between in-process and completed parts are allowed. In the problem, the parts of a single item are first batched,then the resulting batches are processed on a single machine. All completed batches are transported in a number of deliveries in order to be received at a common due date. The objective is to find the integrated schedule of production and delivery batches so as to satisfy its due date and to minimize the total cost of associated in-process parts inventory, completed parts inventory and delivery. It should be noted that both holding costs constitute a derivation of the so-called actual flow time, and the delivery cost is proportional to the required number of deliveries. The problem can be formulated as an integer non-linier programming and it is solved optimally by Lingo 11.0 software. Numerical experiences show that there are two patterns of batch sizes affected by the ratio of holding costs of in-process and completed parts. It can be used by practitioners to solve the realistic integrated production and delivery batch scheduling problem.

  14. Minimizing the cost of splitting in Monte Carlo radiation transport simulation

    Energy Technology Data Exchange (ETDEWEB)

    Juzaitis, R.J.

    1980-10-01

    A deterministic analysis of the computational cost associated with geometric splitting/Russian roulette in Monte Carlo radiation transport calculations is presented. Appropriate integro-differential equations are developed for the first and second moments of the Monte Carlo tally as well as time per particle history, given that splitting with Russian roulette takes place at one (or several) internal surfaces of the geometry. The equations are solved using a standard S/sub n/ (discrete ordinates) solution technique, allowing for the prediction of computer cost (formulated as the product of sample variance and time per particle history, sigma/sup 2//sub s/tau p) associated with a given set of splitting parameters. Optimum splitting surface locations and splitting ratios are determined. Benefits of such an analysis are particularly noteworthy for transport problems in which splitting is apt to be extensively employed (e.g., deep penetration calculations).

  15. Ranking periodic ordering models on the basis of minimizing total inventory cost

    Directory of Open Access Journals (Sweden)

    Mohammadali Keramati

    2015-06-01

    Full Text Available This paper aims to provide proper policies for inventory under uncertain conditions by comparing different inventory policies. To review the efficiency of these algorithms it is necessary to specify the area in which each of them is applied. Therefore, each of the models has been reviewed under different forms of retailing and they are ranked in terms of their expenses. According to the high values of inventories and their impacts on the costs of the companies, the ranking of various models using the simulation annealing algorithm are presented, which indicates that the proposed model of this paper could perform better than other alternative ones. The results also indicate that the suggested algorithm could save from 4 to 29 percent on costs of inventories.

  16. Cost Minimization Analysis of the Use of Meropenem and Ceftazidime in Febrile Neutropenia Therapy

    Directory of Open Access Journals (Sweden)

    Rizky Abdulah

    2016-06-01

    Full Text Available Use of antibiotics is required in febrile neutropenia therapy. The variety choice on the use of antibiotics has increased the role of pharmacoeconomics study to determine the most effective and efficient antibiotic in a specific area. The purpose of this study was to investigate the lowest cost antibiotic between meropenem and ceftazidime that were used as one of febrile neutropenia treatments at one of referral hospitals in West Java province during 2011–2013. This study was a retrospective, observational and analytical study that was performed on February 2014 by collecting medical record data related to febrile neutropenia inpatient who received meropenem or ceftazidime therapy. The result showed that although it was not statistically significant, the total cost for ceftazidime therapy was IDR7,082,523, which was lower than meropenem therapy (IDR11,094,147. Hopefully, this result can assist the health professionals in the management of febrile neutropenia therapy.

  17. Minimizing Wind Power Producer's Balancing Costs Using Electrochemical Energy Storage: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Miettinen, J.; Tikka, V.; Lassila, J.; Partanen, J.; Hodge, B. M.

    2014-08-01

    This paper examines how electrochemical energy storage can be used to decrease the balancing costs of a wind power producer in the Nordic market. Because electrochemical energy storage is developing in both technological and financial terms, a sensitivity analysis was carried out for the most important variables in the wind-storage hybrid system. The system was studied from a wind power producer's point of view. The main result is that there are no technical limitations to using storage for reducing the balancing costs. However, in terms of economic feasibility, installing hybrid wind-storage systems such as the one studied in this paper faces challenges in both the short and long terms.

  18. Minimizing the cost of splitting in Monte Carlo radiation transport simulation

    International Nuclear Information System (INIS)

    A deterministic analysis of the computational cost associated with geometric splitting/Russian roulette in Monte Carlo radiation transport calculations is presented. Appropriate integro-differential equations are developed for the first and second moments of the Monte Carlo tally as well as time per particle history, given that splitting with Russian roulette takes place at one (or several) internal surfaces of the geometry. The equations are solved using a standard S/sub n/ (discrete ordinates) solution technique, allowing for the prediction of computer cost (formulated as the product of sample variance and time per particle history, sigma2/sub s/tau p) associated with a given set of splitting parameters. Optimum splitting surface locations and splitting ratios are determined. Benefits of such an analysis are particularly noteworthy for transport problems in which splitting is apt to be extensively employed

  19. Cost Minimization Analysis of the Use of Meropenem and Ceftazidime in Febrile Neutropenia Therapy

    OpenAIRE

    Rizky Abdulah; Raine D. Kumamba; Rano K. Sinuraya; Cherry Rahayu; Melisa I. Barliana

    2016-01-01

    Use of antibiotics is required in febrile neutropenia therapy. The variety choice on the use of antibiotics has increased the role of pharmacoeconomics study to determine the most effective and efficient antibiotic in a specific area. The purpose of this study was to investigate the lowest cost antibiotic between meropenem and ceftazidime that were used as one of febrile neutropenia treatments at one of referral hospitals in West Java province during 2011–2013. This study was a retrospective,...

  20. Performing flexible control on low-cost microcontrollers using a minimal real-time kernel

    OpenAIRE

    Marau R.; Leite P.; Velasco M.; Marti P.; Almeida L.; Pedreiras P.; Fuertes J.M.

    2008-01-01

    In recent years, approaches to control performance and resource optimization for embedded control systems have been receiving increased attention. Most of them focus on theory, whereas practical aspects are omitted. Theoretical advances demand flexible real-time kernel support for multitasking and preemption, thus requiring more sophisticated and expensive software/ hardware solutions. On the other hand, embedded control systems often have cost constraints related with ma...

  1. Modeling Optimal Scheduling for Pumping System to Minimize Operation Cost and Enhance Operation Reliability

    Directory of Open Access Journals (Sweden)

    Yin Luo

    2012-01-01

    Full Text Available Traditional pump scheduling models neglect the operation reliability which directly relates with the unscheduled maintenance cost and the wear cost during the operation. Just for this, based on the assumption that the vibration directly relates with the operation reliability and the degree of wear, it could express the operation reliability as the normalization of the vibration level. The characteristic of the vibration with the operation point was studied, it could be concluded that idealized flow versus vibration plot should be a distinct bathtub shape. There is a narrow sweet spot (80 to 100 percent BEP to obtain low vibration levels in this shape, and the vibration also follows similar law with the square of the rotation speed without resonance phenomena. Then, the operation reliability could be modeled as the function of the capacity and rotation speed of the pump and add this function to the traditional model to form the new. And contrast with the tradition method, the result shown that the new model could fix the result produced by the traditional, make the pump operate in low vibration, then the operation reliability could increase and the maintenance cost could decrease.

  2. Comprehensive Cost Minimization in Distribution Networks Using Segmented-time Feeder Reconfiguration and Reactive Power Control of Distributed Generators

    DEFF Research Database (Denmark)

    Chen, Shuheng; Hu, Weihao; Chen, Zhe

    2016-01-01

    and distributed generators’ reactive powers in order to minimize comprehensive cost. Corresponding constraints, including voltage profile, maximum allowable daily switching operation numbers (MADSON), reactive power limits, and so on, are considered. The strategy of grouping branches is used to simplify...... (FAHPSO) is implemented in VC++ 6.0 program language. A modified version of the typical 70-node distribution network and several real distribution networks are used to test the performance of the proposed method. Numerical results show that the proposed methodology is an efficient method for comprehensive...

  3. A Minimally Invasive Method for Retrieving Single Adherent Cells of Different Types from Cultures

    OpenAIRE

    Jia Zeng; Aida Mohammadreza; Weimin Gao; Saeed Merza; Dean Smith; Laimonas Kelbauskas; Deirdre R. Meldrum

    2014-01-01

    The field of single-cell analysis has gained a significant momentum over the last decade. Separation and isolation of individual cells is an indispensable step in almost all currently available single-cell analysis technologies. However, stress levels introduced by such manipulations remain largely unstudied. We present a method for minimally invasive retrieval of selected individual adherent cells of different types from cell cultures. The method is based on a combination of mechanical (shea...

  4. Identifying cost-minimizing strategies for guaranteeing target dairy income over feed cost via use of the Livestock Gross Margin dairy insurance program.

    Science.gov (United States)

    Valvekar, M; Cabrera, V E; Gould, B W

    2010-07-01

    Milk and feed price volatility are the major source of dairy farm risk. Since August 2008 a new federally reinsured insurance program has been available to many US dairy farmers to help minimize the negative effects of adverse price movements. This insurance program is referred to as Livestock Gross Margin Insurance for Dairy Cattle. Given the flexibility in contract design, the dairy farmer has to make 3 critical decisions when purchasing this insurance: 1) the percentage of monthly milk production to be covered, 3) declared feed equivalents used to produce this milk, and 3) the level of gross margin not covered by insurance (i.e., deductible). The objective of this analysis was to provide an optimal strategy of how a dairy farmer could incorporate this insurance program to help manage the variability in net farm income. In this analysis we assumed that a risk-neutral dairy farmer wants to design an insurance contract such that a target guaranteed income over feed cost is obtained at least cost. We undertook this analysis for a representative Wisconsin dairy farm (herd size: 120 cows) producing 8,873 kg (19,545 lb) of milk/cow per year. Wisconsin statistical data indicates that dairy farms of similar size must require an income over feed cost of at least $110/Mg ($5/cwt) of milk to be profitable during the coverage period. Therefore, using data for the July 2009 insurance contract to insure $110/Mg of milk, the least cost contract was found to have a premium of $1.22/Mg ($0.055/cwt) of milk produced insuring approximately 52% of the production with variable monthly production covered during the period of September 2009 to June 2010. This premium represented 1.10% of the desired IOFC. We compared the above optimal strategy with an alternative nonoptimal strategy, defined as a contract insuring the same proportion of milk as the optimal (52%) but with a constant amount insured across all contract months. The premium was found to be almost twice the level obtained

  5. Minimizing the Levelized Cost of Energy in Single-Phase Photovoltaic Systems with an Absolute Active Power Control

    DEFF Research Database (Denmark)

    Yang, Yongheng; Koutroulis, Eftichios; Sangwongwanich, Ariya;

    2016-01-01

    Countries with considerable PhotoVoltaic (PV) installations are facing a challenge of overloading their power grid during peak-power production hours if the power infrastructure remains the same. To address this, regulations have been imposed on PV systems, where more active power control should...... be flexibly performed. As an advanced control strategy, the Absolute Active Power Control (AAPC) can effectively solve the overloading issues by limiting the maximum possible PV power to a certain level (i.e., the power limitation), and also benefit the inverter reliability due to the reduction in the thermal...... loading of the power devices. However, its feasibility is challenged by the associated energy losses. An increase of the inverter lifetime and a reduction of the energy yield can alter the cost of energy, demanding an optimization of the power limitation. Therefore, aiming at minimizing the Levelized Cost...

  6. Minimizing the Levelized Cost of Energy in Single-Phase Photovoltaic Systems with an Absolute Active Power Control

    DEFF Research Database (Denmark)

    Yang, Yongheng; Koutroulis, Eftichios; Sangwongwanich, Ariya;

    2015-01-01

    Several countries with considerable PhotoVoltaic (PV) installations are facing a challenge of overloading the power infrastructure during peak-power production hours. Regulations have been imposed on the PV systems, where more active power control should be flexibly performed. As an advanced...... control strategy, the Absolute Active Power Control (AAPC) can effectively solve the overloading issues by limiting the maximum possible PV power to a certain level (i.e., the power limitation), and also benefit the inverter reliability. However, its feasibility is challenged by the energy loss....... An increase of the inverter lifetime and a reduction of the energy yield can alter the cost of energy, demanding an optimization of the power limitation. Therefore, aiming at minimizing the Levelized Cost of Energy (LCOE), the power limit is optimized for the AAPC strategy in this paper. The optimization...

  7. SLA-constrained service selection for minimizing costs of providing composite cloud services under stochastic runtime performance.

    Science.gov (United States)

    Huang, Kuo-Chan; Tsai, Mu-Jung; Lu, Sin-Ji; Hung, Chun-Hao

    2016-01-01

    Composite cloud services based on the methodologies of Software as a Service and Service-Oriented Architecture are transforming how people develop and use software. Cloud service providers are confronting the service selection problem when composing composite cloud services. This paper deals with an important type of service selection problem, minimizing the total cost of providing a composite cloud service with respect to the constraints of service level agreement (SLA). Two types of SLA are considered in the study: per-request-based SLA and ratio-based SLA. We present three service selection approaches for dynamic cloud environments where services' performance might vary with time. The first two are iterative compound approaches for per-request-based SLA and the third approach is a one-step method for ratio-based SLA based on the Chebyshev's theorem and nonlinear programming. Experimental results show that our approaches outperform the previous method significantly in terms of total cost reduction. PMID:27066331

  8. A Comprehensive Mathematical Programming Model for Minimizing Costs in A Multiple-Item Reverse Supply Chain with Sensitivity Analysis

    Directory of Open Access Journals (Sweden)

    Mahmoudi Hoda

    2014-09-01

    Full Text Available These instructions give you guidelines for preparing papers for IFAC conferences. A reverse supply chain is configured by a sequence of elements forming a continuous process to treat return-products until they are properly recovered or disposed. The activities in a reverse supply chain include collection, cleaning, disassembly, test and sorting, storage, transport, and recovery operations. This paper presents a mathematical programming model with the objective of minimizing the total costs of reverse supply chain including transportation, fixed opening, operation, maintenance and remanufacturing costs of centers. The proposed model considers the design of a multi-layer, multi-product reverse supply chain that consists of returning, disassembly, processing, recycling, remanufacturing, materials and distribution centers. This integer linear programming model is solved by using Lingo 9 software and the results are reported. Finally, a sensitivity analysis of the proposed model is also presented.

  9. Smart control for minimizing distribution network reinforcement cost due to electrification

    International Nuclear Information System (INIS)

    Electrification of transport fleets and heating sectors is seen as one of the key strategies to further reduce the use of fossil fuels and the resulting greenhouse gas emissions. However, it will potentially cause a significant increase of electricity peak demand and have adverse consequences on the electricity system, in particular on distribution networks. This paper will address the benefits of various applications of smart network control and demand response technologies for enhancing the integration of these future load categories, and for improvements in operation management and efficient use of distribution network assets. A range of numerical simulations have been carried out on different distribution network topologies (rural and urban networks) to identify the need and the cost of network reinforcement required to accommodate future load under various operating strategies such as Business as Usual (passive demand and passive network) against the smart grid approach. Applications of smart Plug-in vehicle (PiV) charging, smart heat pumps, and optimised control of network voltage regulators to reduce network investment have been studied, and selected key results of our studies on evaluating the benefits of implementing these technologies for Great Britain's distribution networks are presented and discussed in this paper. - Highlights: ► Growth of electricity loads driven by electrification of transport and heat will be significant. ► It will increase the electricity peak demand up to 2–3 times and cost tens of billion pounds if we maintain Business as Usual approach. ► A coordinated application of smart demand technologies can significantly reduce this cost. ► It requires sets of policies and regulations to facilitate timely deployment of such technologies.

  10. PSO for Multiobjective Economic Load Dispatch (MELD) for Minimizing Generation Cost and Transmission Losses

    Science.gov (United States)

    Jain, Narender Kumar; Nangia, Uma; Jain, Aishwary

    2016-06-01

    In this paper, multiobjective economic load dispatch (MELD) problem considering generation cost and transmission losses has been formulated using priority goal programming (PGP) technique. In this formulation, equality constraint has been considered by inclusion of penalty parameter K. It has been observed that fixing its value to 1,000 keeps the equality constraint within limits. The non-inferior set for IEEE 5, 14 and 30-bus systems has been generated by Particle Swarm Optimization (PSO) technique. The best compromise solution has been chosen as the one which gives equal percentage saving for both the objectives.

  11. Minimal Resources with Maximum Impact: Low-Cost and Sustainable Means for Library Promotions

    OpenAIRE

    Sagun, Karryl Kim A.

    2014-01-01

    While it is a generally shared fact around the globe that funding for library promotion (and in most cases, libraries in general) be rendered as a pressing concern, the fact remains that this challenge is truer in developing countries such as the Philippines. Librarians in charge of promoting the library can either choose to fight--defend their “rights” for a slice of the budget pie, or take flight--just do away with library promotion altogether. However, results of a low-cost and sustainable...

  12. Cost-minimization analysis of sublingual immunotherapy versus subcutaneous immunotherapy for house dust mite respiratory allergic disease in Denmark.

    Science.gov (United States)

    Rønborg, Steen; Johnsen, Claus R; Theilgaard, Sune; Winther, Anders; Hahn-Pedersen, Julie; Andreasen, Jakob Nørgaard; Olsen, Jens

    2016-08-01

    Objectives Currently, patients with persistent moderate-to-severe house dust mite (HDM) allergic rhinitis despite use of symptom-relieving medication can be offered subcutaneously administered allergy immunotherapy (SQ SCIT; Alutard SQ) as standard care of treatment in Denmark. Recently, a HDM sublingually administered allergy immunotherapy tablet (SQ SLIT-tablet; ACARIZAX) has been developed for at-home treatment. The purpose of this analysis is to compare the costs related to treatment and administration of SQ SLIT-tablet and SQ SCIT. Methods Assuming equal efficacy between ther SQ SLIT-tablet and SQ SCIT, the cost-minimization analysis was the most appropriate for the comparison. According to guidelines and Summary of Product Characteristics, the treatment duration of SQ SLIT-tablet is 3 years and 3-5 years for SQ SCIT. The courses of treatment vary among patients and, therefore, the costs of treatment have been calculated for an average patient with HDM respiratory allergic disease (RAD) receiving either SQ SLIT-tablet or SQ SCIT. All costs associated with allergy immunotherapy were collected, i.e., cost of medication, administration and treatment setting, and discounted according to Danish guidelines. Comprehensive univariate sensitivity analyses were carried out. Results The treatment costs for an average patient with HDM RAD are €3094 for SQ SLIT-tablet and €3799 for SQ SCIT; however, when adding indirect costs to the calculations the total costs of the treatments are €3697 and €6717 for SQ SLIT-tablet and SQ SCIT, respectively. Therefore, if 2500 patients with HDM RAD were treated with SQ SLIT-tablet instead of SQ SCIT, it would elicit a saving to the healthcare system of ∼€1.8 million. The conclusion was robust to any changes in the sensitivity analysis. Conclusion With regards to the cost of treating Danish patients with HDM RAD, it is clearly cost-saving to treat patients with SQ SLIT-tablet compared to SQ SCIT. PMID:26909663

  13. Towards Minimizing Computational Cost of Range Aggregates against Uncertain Location-Based Queries

    Directory of Open Access Journals (Sweden)

    Y.Rajasekhar

    2013-11-01

    Full Text Available Queries which are location based are unsure in nature. Such queries are become common in many real time applications where location based services are cause to be. Multi-dimensional search space is effective use of such applications. Processing unsure location based queries accurately is a tough task. This paper handles a new algorithm to handle such queries. It makes utilize of range aggregates like count, avg, sum etc. for query processing. The algorithm calculates range aggregates proficiently so as to support correct result making. We built a model application for testing the future algorithm. The investigational results showed that the application is proficient of processing uncertain location based queries efficiently consuming less processing power and computation cost.

  14. Health costs of reproduction are minimal despite high fertility, mortality and subsistence lifestyle.

    Science.gov (United States)

    Gurven, Michael; Costa, Megan; Ben Trumble; Stieglitz, Jonathan; Beheim, Bret; Eid Rodriguez, Daniel; Hooper, Paul L; Kaplan, Hillard

    2016-01-01

    Women exhibit greater morbidity than men despite higher life expectancy. An evolutionary life history framework predicts that energy invested in reproduction trades-off against investments in maintenance and survival. Direct costs of reproduction may therefore contribute to higher morbidity, especially for women given their greater direct energetic contributions to reproduction. We explore multiple indicators of somatic condition among Tsimane forager-horticulturalist women (Total Fertility Rate = 9.1; n =  592 aged 15-44 years, n = 277 aged 45+). We test whether cumulative live births and the pace of reproduction are associated with nutritional status and immune function using longitudinal data spanning 10 years. Higher parity and faster reproductive pace are associated with lower nutritional status (indicated by weight, body mass index, body fat) in a cross-section, but longitudinal analyses show improvements in women's nutritional status with age. Biomarkers of immune function and anemia vary little with parity or pace of reproduction. Our findings demonstrate that even under energy-limited and infectious conditions, women are buffered from the potential depleting effects of rapid reproduction and compound offspring dependency characteristic of human life histories. PMID:27436412

  15. Minimizing total costs of forest roads with computer-aided design model

    Indian Academy of Sciences (India)

    Abdullah E Akay

    2006-10-01

    Advances in personal computers (PCs) have increased interest in computer-based road-design systems to provide rapid evaluation of alternative alignments. Optimization techniques can provide road managers with a powerful tool that searches for large numbers of alternative alignments in short spans of time. A forest road optimization model, integrated with two optimization techniques, was developed to help a forest road engineer in evaluating alternative alignments in a faster and more systematic manner. The model aims at designing a path with minimum total road costs, while conforming to design specifications, environmental requirements, and driver safety. To monitor the sediment production of the alternative alignments, the average sediment delivered to a stream from a road section was estimated by using a road erosion/delivery model. The results indicated that this model has the potential to initiate a new procedure that will improve the forest road-design process by employing the advanced hardware and software capabilities of PCs and modern optimization techniques.

  16. Truthful Incentive Mechanisms for Social Cost Minimization in Mobile Crowdsourcing Systems

    Directory of Open Access Journals (Sweden)

    Zhuojun Duan

    2016-04-01

    Full Text Available With the emergence of new technologies, mobile devices are capable of undertaking computational and sensing tasks. A large number of users with these mobile devices promote the formation of the Mobile Crowdsourcing Systems (MCSs. Within a MCS, each mobile device can contribute to the crowdsourcing platform and get rewards from it. In order to achieve better performance, it is important to design a mechanism that can attract enough participants with mobile devices and then allocate the tasks among participants efficiently. In this paper, we are interested in the investigation of tasks allocation and price determination in MCSs. Two truthful auction mechanisms are proposed for different working patterns. A Vickrey–Clarke–Groves (VCG-based auction mechanism is proposed to the continuous working pattern, and a suboptimal auction mechanism is introduced for the discontinuous working pattern. Further analysis shows that the proposed mechanisms have the properties of individual rationality and computational efficiencies. Experimental results suggest that both mechanisms guarantee all the mobile users bidding with their truthful values and the optimal maximal social cost can be achieved in the VCG-based auction mechanism.

  17. Oxygen-consuming chlor alkali cell configured to minimize peroxide formation

    Science.gov (United States)

    Chlistunoff, Jerzy B.; Lipp, Ludwig; Gottesfeld, Shimshon

    2006-08-01

    Oxygen-consuming zero gap chlor-alkali cell was configured to minimize peroxide formation. The cell included an ion-exchange membrane that divided the cell into an anode chamber including an anode and a cathode chamber including an oxygen gas diffusion cathode. The cathode included a single-piece of electrically conducting graphitized carbon cloth. Catalyst and polytetrafluoroethylene were attached to only one side of the cloth. When the cathode was positioned against the cation exchange membrane with the catalyst side away from the membrane, electrolysis of sodium chloride to chlorine and caustic (sodium hydroxide) proceeded with minimal peroxide formation.

  18. Make or buy analysis model based on tolerance allocation to minimize manufacturing cost and fuzzy quality loss

    Science.gov (United States)

    Rosyidi, C. N.; Puspitoingrum, W.; Jauhari, W. A.; Suhardi, B.; Hamada, K.

    2016-02-01

    The specification of tolerances has a significant impact on the quality of product and final production cost. The company should carefully pay attention to the component or product tolerance so they can produce a good quality product at the lowest cost. Tolerance allocation has been widely used to solve problem in selecting particular process or supplier. But before merely getting into the selection process, the company must first make a plan to analyse whether the component must be made in house (make), to be purchased from a supplier (buy), or used the combination of both. This paper discusses an optimization model of process and supplier selection in order to minimize the manufacturing costs and the fuzzy quality loss. This model can also be used to determine the allocation of components to the selected processes or suppliers. Tolerance, process capability and production capacity are three important constraints that affect the decision. Fuzzy quality loss function is used in this paper to describe the semantic of the quality, in which the product quality level is divided into several grades. The implementation of the proposed model has been demonstrated by solving a numerical example problem that used a simple assembly product which consists of three components. The metaheuristic approach were implemented to OptQuest software from Oracle Crystal Ball in order to obtain the optimal solution of the numerical example.

  19. Cost-minimized combinations of wind power, solar power and electrochemical storage, powering the grid up to 99.9% of the time

    DEFF Research Database (Denmark)

    Budischak, Cory; Sewell, DeAnna; Thomson, Heather;

    2013-01-01

    intermittent power, we seek combinations of diverse renewables at diverse sites, with storage, that are not intermittent and satisfy need a given fraction of hours. And 2) we seek minimal cost, calculating true cost of electricity without subsidies and with inclusion of external costs. Our model evaluated over...... renewable generation and the excess capacity together meet electric load with less storage, lowering total system cost. At 2030 technology costs and with excess electricity displacing natural gas, we find that the electric system can be powered 90%–99.9% of hours entirely on renewable electricity, at costs...

  20. Update of a comparative analysis of cost minimization following the introduction of newly available intravenous iron therapies in hospital practice

    Directory of Open Access Journals (Sweden)

    Bhandari S

    2011-12-01

    carboxymaltose are more economical than low molecular weight iron dextran. Iron isomaltoside 1000 is less expensive than ferric carboxymaltose at all dose levels. Newly available iron preparations appear to be clinically promising, cost effective, and practical alternatives to current standards of iron repletion.Keywords: iron isomaltoside 1000, ferric carboxymaltose, iron deficiency anemia, single high dose, IV iron, cost minimization

  1. Minimizing investment cost for multi-period heat exchanger network retrofit by matching heat transfer areas with different strategies

    Institute of Scientific and Technical Information of China (English)

    Lixia Kang; Yongzhong Liu

    2015-01-01

    Multi-period heat exchanger network (HEN) retrofit is usually performed by targeting and matching heat trans-fer areas. In this paper, based on the reverse order matching method we proposed previously, three strategies of matching heat transfer areas are proposed to minimize the investment cost for the retrofit of HEN in multi-period, in which replacement of heat exchangers, addition of heat exchangers and addition of heat transfer areas are performed. We demonstrate the procedures through three scenarios, including maximum number of substituted heat exchangers after retrofit, minimum additional heat transfer areas in the retrofitted HEN, and minimum investment cost for retrofit. The strategies are extended to a single period HEN retrofit problem. The results of multi-period and single period HEN retrofit problems indicate the effectiveness of the strategies. More-over, these results are better than those reported in literature. The strategies are simple and easy to implement, which are of great benefit to large-scale HEN retrofit in practice.

  2. Minimal RED Cell Pairs Markedly Improve Electrode Kinetics and Power Production in Microbial Reverse Electrodialysis Cells

    KAUST Repository

    Cusick, Roland D.

    2013-12-17

    Power production from microbial reverse electrodialysis cell (MRC) electrodes is substantially improved compared to microbial fuel cells (MFCs) by using ammonium bicarbonate (AmB) solutions in multiple RED cell pair stacks and the cathode chamber. Reducing the number of RED membranes pairs while maintaining enhanced electrode performance could help to reduce capital costs. We show here that using only a single RED cell pair (CP), created by operating the cathode in concentrated AmB, dramatically increased power production normalized to cathode area from both acetate (Acetate: from 0.9 to 3.1 W/m 2-cat) and wastewater (WW: 0.3 to 1.7 W/m2), by reducing solution and charge transfer resistances at the cathode. A second RED cell pair increased RED stack potential and reduced anode charge transfer resistance, further increasing power production (Acetate: 4.2 W/m2; WW: 1.9 W/m2). By maintaining near optimal electrode power production with fewer membranes, power densities normalized to total membrane area for the 1-CP (Acetate: 3.1 W/m2-mem; WW: 1.7 W/m2) and 2-CP (Acetate: 1.3 W/m2-mem; WW: 0.6 W/m2) reactors were much higher than previous MRCs (0.3-0.5 W/m2-mem with acetate). While operating at peak power, the rate of wastewater COD removal, normalized to reactor volume, was 30-50 times higher in 1-CP and 2-CP MRCs than that in a single chamber MFC. These findings show that even a single cell pair AmB RED stack can significantly enhance electrical power production and wastewater treatment. © 2013 American Chemical Society.

  3. Computed tomography for preoperative planning in minimal-invasive total hip arthroplasty: Radiation exposure and cost analysis

    International Nuclear Information System (INIS)

    Computed tomography (CT) was used for preoperative planning of minimal-invasive total hip arthroplasty (THA). 92 patients (50 males, 42 females, mean age 59.5 years) with a mean body-mass-index (BMI) of 26.5 kg/m2 underwent 64-slice CT to depict the pelvis, the knee and the ankle in three independent acquisitions using combined x-, y-, and z-axis tube current modulation. Arthroplasty planning was performed using 3D-Hip Plan (Symbios, Switzerland) and patient radiation dose exposure was determined. The effects of BMI, gender, and contralateral THA on the effective dose were evaluated by an analysis-of-variance. A process-cost-analysis from the hospital perspective was done. All CT examinations were of sufficient image quality for 3D-THA planning. A mean effective dose of 4.0 mSv (SD 0.9 mSv) modeled by the BMI (p < 0.0001) was calculated. The presence of a contralateral THA (9/92 patients; p = 0.15) and the difference between males and females were not significant (p = 0.08). Personnel involved were the radiologist (4 min), the surgeon (16 min), the radiographer (12 min), and administrative personnel (4 min). A CT operation time of 11 min and direct per-patient costs of 52.80 Euro were recorded. Preoperative CT for THA was associated with a slight and justifiable increase of radiation exposure in comparison to conventional radiographs and low per-patient costs.

  4. Computed tomography for preoperative planning in minimal-invasive total hip arthroplasty: radiation exposure and cost analysis.

    Science.gov (United States)

    Huppertz, Alexander; Radmer, Sebastian; Asbach, Patrick; Juran, Ralf; Schwenke, Carsten; Diederichs, Gerd; Hamm, Bernd; Sparmann, Martin

    2011-06-01

    Computed tomography (CT) was used for preoperative planning of minimal-invasive total hip arthroplasty (THA). 92 patients (50 males, 42 females, mean age 59.5 years) with a mean body-mass-index (BMI) of 26.5 kg/m(2) underwent 64-slice CT to depict the pelvis, the knee and the ankle in three independent acquisitions using combined x-, y-, and z-axis tube current modulation. Arthroplasty planning was performed using 3D-Hip Plan(®) (Symbios, Switzerland) and patient radiation dose exposure was determined. The effects of BMI, gender, and contralateral THA on the effective dose were evaluated by an analysis-of-variance. A process-cost-analysis from the hospital perspective was done. All CT examinations were of sufficient image quality for 3D-THA planning. A mean effective dose of 4.0 mSv (SD 0.9 mSv) modeled by the BMI (p<0.0001) was calculated. The presence of a contralateral THA (9/92 patients; p=0.15) and the difference between males and females were not significant (p=0.08). Personnel involved were the radiologist (4 min), the surgeon (16 min), the radiographer (12 min), and administrative personnel (4 min). A CT operation time of 11 min and direct per-patient costs of 52.80 € were recorded. Preoperative CT for THA was associated with a slight and justifiable increase of radiation exposure in comparison to conventional radiographs and low per-patient costs. PMID:20022723

  5. Computed tomography for preoperative planning in minimal-invasive total hip arthroplasty: Radiation exposure and cost analysis

    Energy Technology Data Exchange (ETDEWEB)

    Huppertz, Alexander, E-mail: Alexander.Huppertz@charite.de [Imaging Science Institute Charite Berlin, Robert-Koch-Platz 7, D-10115 Berlin (Germany); Department of Radiology, Medical Physics, Charite-University Hospitals of Berlin, Chariteplatz 1, D-10117 Berlin (Germany); Radmer, Sebastian, E-mail: s.radmer@immanuel.de [Department of Orthopedic Surgery and Rheumatology, Immanuel-Krankenhaus, Koenigstr. 63, D-14109, Berlin (Germany); Asbach, Patrick, E-mail: Patrick.Asbach@charite.de [Department of Radiology, Medical Physics, Charite-University Hospitals of Berlin, Chariteplatz 1, D-10117 Berlin (Germany); Juran, Ralf, E-mail: ralf.juran@charite.de [Department of Radiology, Medical Physics, Charite-University Hospitals of Berlin, Chariteplatz 1, D-10117 Berlin (Germany); Schwenke, Carsten, E-mail: carsten.schwenke@scossis.de [Biostatistician, Scossis Statistical Consulting, Zeltinger Str. 58G, D-13465 Berlin (Germany); Diederichs, Gerd, E-mail: gerd.diederichs@charite.de [Department of Radiology, Medical Physics, Charite-University Hospitals of Berlin, Chariteplatz 1, D-10117 Berlin (Germany); Hamm, Bernd, E-mail: Bernd.Hamm@charite.de [Department of Radiology, Medical Physics, Charite-University Hospitals of Berlin, Chariteplatz 1, D-10117 Berlin (Germany); Sparmann, Martin, E-mail: m.sparmann@immanuel.de [Department of Orthopedic Surgery and Rheumatology, Immanuel-Krankenhaus, Koenigstr. 63, D-14109, Berlin (Germany)

    2011-06-15

    Computed tomography (CT) was used for preoperative planning of minimal-invasive total hip arthroplasty (THA). 92 patients (50 males, 42 females, mean age 59.5 years) with a mean body-mass-index (BMI) of 26.5 kg/m{sup 2} underwent 64-slice CT to depict the pelvis, the knee and the ankle in three independent acquisitions using combined x-, y-, and z-axis tube current modulation. Arthroplasty planning was performed using 3D-Hip Plan (Symbios, Switzerland) and patient radiation dose exposure was determined. The effects of BMI, gender, and contralateral THA on the effective dose were evaluated by an analysis-of-variance. A process-cost-analysis from the hospital perspective was done. All CT examinations were of sufficient image quality for 3D-THA planning. A mean effective dose of 4.0 mSv (SD 0.9 mSv) modeled by the BMI (p < 0.0001) was calculated. The presence of a contralateral THA (9/92 patients; p = 0.15) and the difference between males and females were not significant (p = 0.08). Personnel involved were the radiologist (4 min), the surgeon (16 min), the radiographer (12 min), and administrative personnel (4 min). A CT operation time of 11 min and direct per-patient costs of 52.80 Euro were recorded. Preoperative CT for THA was associated with a slight and justifiable increase of radiation exposure in comparison to conventional radiographs and low per-patient costs.

  6. Cost and Performance Tradeoff Analysis of Cell Planning Levels

    OpenAIRE

    Gao, Jun

    2013-01-01

    In wireless communication systems, optimal placement of base station locations, i.e.,cell planning, has been considered one of major tools for performance improvement.However, the cell planning requires signicant eort for acquiring suitable sites aswell as expensive computer software for nding out optimal locations. While theprice of equipment has dropped rapidly, the cost of cell planing remains similar orbecomes even more costly with increasing complexity of wireless systems.Therefore,the c...

  7. An interval-based possibilistic programming method for waste management with cost minimization and environmental-impact abatement under uncertainty

    International Nuclear Information System (INIS)

    Considerable public concerns have been raised in the past decades since a large amount of pollutant emissions from municipal solid waste (MSW) disposal of processes pose risks on surrounding environment and human health. Moreover, in MSW management, various uncertainties exist in the related costs, impact factors and objectives, which can affect the optimization processes and the decision schemes generated. In this study, an interval-based possibilistic programming (IBPP) method is developed for planning the MSW management with minimized system cost and environmental impact under uncertainty. The developed method can deal with uncertainties expressed as interval values and fuzzy sets in the left- and right-hand sides of constraints and objective function. An interactive algorithm is provided for solving the IBPP problem, which does not lead to more complicated intermediate submodels and has a relatively low computational requirement. The developed model is applied to a case study of planning a MSW management system, where mixed integer linear programming (MILP) technique is introduced into the IBPP framework to facilitate dynamic analysis for decisions of timing, sizing and siting in terms of capacity expansion for waste-management facilities. Three cases based on different waste-management policies are examined. The results obtained indicate that inclusion of environmental impacts in the optimization model can change the traditional waste-allocation pattern merely based on the economic-oriented planning approach. The results obtained can help identify desired alternatives for managing MSW, which has advantages in providing compromised schemes under an integrated consideration of economic efficiency and environmental impact under uncertainty.

  8. On the road to synthetic life: the minimal cell and genome-scale engineering.

    Science.gov (United States)

    Juhas, Mario

    2016-06-01

    Synthetic biology employs rational engineering principles to build biological systems from the libraries of standard, well characterized biological parts. Biological systems designed and built by synthetic biologists fulfill a plethora of useful purposes, ranging from better healthcare and energy production to biomanufacturing. Recent advancements in the synthesis, assembly and "booting-up" of synthetic genomes and in low and high-throughput genome engineering have paved the way for engineering on the genome-wide scale. One of the key goals of genome engineering is the construction of minimal genomes consisting solely of essential genes (genes indispensable for survival of living organisms). Besides serving as a toolbox to understand the universal principles of life, the cell encoded by minimal genome could be used to build a stringently controlled "cell factory" with a desired phenotype. This review provides an update on recent advances in the genome-scale engineering with particular emphasis on the engineering of minimal genomes. Furthermore, it presents an ongoing discussion to the scientific community for better suitability of minimal or robust cells for industrial applications. PMID:25578717

  9. Secant generalized method minimizing the fuel and emissions costs in a power station of small cogeneration multi-machines

    International Nuclear Information System (INIS)

    The objective of this paper consists in optimizing the fuel consumption of a power station of small cogeneration multi-machines while minimizing generated pollution (CO and NOx). Firstly, a study carried out on the strategies of Economic Dispatch was used to solve the unit commitment problem, whose main goals is to determine the optimal schedule of online generating units so as to meet the power demand at minimum fuel and emission costs under various system and operating constraints. This work was carried out by Secant method combined with Improved Pre-prepared Power Demand (IPPD) table which determines the unit status information; the optimal solution is then achieved by Secant method at each power demand for 24 hours. The proposed algorithm was generalized to 10-100 units in a 24 hours unit commitment schedule. Finally, by comparing the results obtained by our suggested method with the results of the classical method, we find that the method suggested (Secant) provides at any hour the better solution. (authors)

  10. MADM Technique Integrated with Grey- based Taguchi method for Selection of Alluminium alloys to minimize deburring cost during Drilling

    Directory of Open Access Journals (Sweden)

    Reddy Sreenivasulu

    2015-06-01

    Full Text Available Traditionally, burr problems had been considered unavoidable so that most efforts had been made on removal of the burr as a post process. Nowadays, a trend of manufacturing is an integration of the whole production flow from design to end product. Manufacturing problem issues are handled in various stages even from design stage. Therefore, the methods of describing the burr are getting much attention in recent years for the systematic approach to resolve the burr problem at various manufacturing stages. The main objective of this paper is to explore the basic concepts of MADM methods. In this study, five parameters namely speed, feed, drill size, drill geometry such as point angle and clearance angle were identified to influence more on burr formation during drilling. L 18 orthogonal array was selected and experiments were conducted as per Taguchi experimental plan for Aluminium alloy of 2014, 6061, 5035 and 7075 series. The experiment performed on a CNC Machining center with HSS twist drills. The burr size such as height and thickness were measured on exit of each hole. An optimal combination of process parameters was obtained to minimize the burr size via grey relational analysis. The output from grey based- taguchi method fed as input to the MADM. Apart from burr size strength and temperature are also considered as attributes. Finally, the results generated in MADM suggests the suitable alternative of  aluminium alloy, which results in less deburring cost, high strength and high resistance at elevated temperatures.

  11. Variational method for the minimization of entropy generation in solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Smit, Sjoerd; Kessels, W. M. M., E-mail: w.m.m.kessels@tue.nl [Department of Applied Physics, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven (Netherlands)

    2015-04-07

    In this work, a method is presented to extend traditional solar cell simulation tools to make it possible to calculate the most efficient design of practical solar cells. The method is based on the theory of nonequilibrium thermodynamics, which is used to derive an expression for the local entropy generation rate in the solar cell, making it possible to quantify all free energy losses on the same scale. The framework of non-equilibrium thermodynamics can therefore be combined with the calculus of variations and existing solar cell models to minimize the total entropy generation rate in the cell to find the most optimal design. The variational method is illustrated by applying it to a homojunction solar cell. The optimization results in a set of differential algebraic equations, which determine the optimal shape of the doping profile for given recombination and transport models.

  12. A Cost Roadmap for Silicon Heterojunction Solar Cells

    NARCIS (Netherlands)

    Louwen, A.; van Sark, W.G.J.H.M.; Schropp, Ruud; Faaij, A.

    2016-01-01

    Research and development of silicon heterojunction (SHJ) solar cells has seen a marked increase since the recent expiry of core patents describing SHJ technology. SHJ solar cells are expected to offer various cost benefits compared to conventional crystalline silicon solar cells. This paper analyses

  13. Comparison of the costs of nonoperative care to minimally invasive surgery for sacroiliac joint disruption and degenerative sacroiliitis in a United States commercial payer population: potential economic implications of a new minimally invasive technology

    Directory of Open Access Journals (Sweden)

    Ackerman SJ

    2014-05-01

    Full Text Available Stacey J Ackerman,1 David W Polly Jr,2 Tyler Knight,3 Karen Schneider,4 Tim Holt,5 John Cummings Jr6 1Covance Market Access Services Inc., San Diego, CA, USA; 2University of Minnesota, Orthopaedic Surgery, Minneapolis, MN, USA; 3Covance Market Access Services Inc., Gaithersburg, MD, USA; 4Covance Market Access Services Inc., Sydney, Australia; 5Montgomery Spine Center, Orthopedic Surgery, Montgomery, AL, USA; 6Community Health Network, Neurosurgery, Indianapolis, IN, USA Introduction: Low back pain is common and treatment costly with substantial lost productivity and lost wages in the working-age population. Chronic low back pain originating in the sacroiliac (SI joint (15%–30% of cases is commonly treated with nonoperative care, but new minimally invasive surgery (MIS options are also effective in treating SI joint disruption. We assessed whether the higher initial MIS SI joint fusion procedure costs were offset by decreased nonoperative care costs from a US commercial payer perspective. Methods: An economic model compared the costs of treating SI joint disruption with either MIS SI joint fusion or continued nonoperative care. Nonoperative care costs (diagnostic testing, treatment, follow-up, and retail pharmacy pain medication were from a retrospective study of Truven Health MarketScan® data. MIS fusion costs were based on the Premier's Perspective™ Comparative Database and professional fees on 2012 Medicare payment for Current Procedural Terminology code 27280. Results: The cumulative 3-year (base-case analysis and 5-year (sensitivity analysis differentials in commercial insurance payments (cost of nonoperative care minus cost of MIS were $14,545 and $6,137 per patient, respectively (2012 US dollars. Cost neutrality was achieved at 6 years; MIS costs accrued largely in year 1 whereas nonoperative care costs accrued over time with 92% of up front MIS procedure costs offset by year 5. For patients with lumbar spinal fusion, cost neutrality

  14. Low-Cost Multi-Junction Photovoltaic Cells Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The proposed SBIR project will provide a pathway to dramatically reduce the cost of multi-junction solar cells. The project leverages a TRL6 micropackaging process...

  15. Crawling and turning in a minimal reaction-diffusion cell motility model: coupling cell shape and biochemistry

    CERN Document Server

    Camley, Brian A; Li, Bo; Levine, Herbert; Rappel, Wouter-Jan

    2016-01-01

    We study a minimal model of a crawling eukaryotic cell with a chemical polarity controlled by a reaction-diffusion mechanism describing Rho GTPase dynamics. The size, shape, and speed of the cell emerge from the combination of the chemical polarity, which controls the locations where actin polymerization occurs, and the physical properties of the cell, including its membrane tension. We find in our model both highly persistent trajectories, in which the cell crawls in a straight line, and turning trajectories, where the cell transitions from crawling in a line to crawling in a circle. We discuss the controlling variables for this turning instability, and argue that turning arises from a coupling between the reaction-diffusion mechanism and the shape of the cell. This emphasizes the surprising features that can arise from simple links between cell mechanics and biochemistry. Our results suggest that similar instabilities may be present in a broad class of biochemical descriptions of cell polarity.

  16. Angiomyolipoma with minimal fat: Differentiation from papillary renal cell carcinoma by helical CT

    International Nuclear Information System (INIS)

    Aim: To evaluate whether helical computed tomography (CT) images can be used to differentiate angiomyolipomas (AMLs) with minimal fat from papillary renal cell carcinomas (PRCCs) based on their morphological characteristics and enhancement features. Materials and methods: This retrospective study was approved by the institutional review board. Informed consent was waived. Forty-four patients (21 with AMLs with minimal fat and 23 with PRCCs) who underwent enhanced helical CT before total or partial nephrectomy were included. Two radiologists, who were blinded to the histopathology results, read the CT images and recorded the attenuation value, morphological characteristics, and enhancement features of the tumours, which were subsequently evaluated. An independent samples t-test, χ2 test, and rank sum test were performed between the tumours. The predictive value of a CT finding was determined by multivariate logistic regression analysis. Results: AML with minimal fat had an apparent female prevalence (p < 0.01). Intra-tumoural vessels were noted in 11 cases of AML with minimal fat and three PRCC cases (p < 0.01). The unenhanced attenuation characteristic was significantly different between the two diseases (p < 0.001). The absolute attenuation values (AAVs) and the corrected attenuation values (CAVs) of the AML with minimal fat group of unenhanced and two phases of enhanced images were greater compared with that of the PRCC group (p < 0.05). After contrast medium injection, the tumour enhancement value (TEV) of the AML with minimal fat group in the corticomedullary phase was greater than that of the PRCC group (p < 0.01). Most cases of both tumour types demonstrated early enhancement characteristics; the enhancement value of the AML with minimal fat group was greater compared with that of the PRCC group (p < 0.01). The unenhanced attenuation characteristic, intra-tumoural vessels, and CAVs of unenhanced and early excretory phase scans were valuable parameters to

  17. Optimal Control of a PEM Fuel Cell for the Inputs Minimization

    Directory of Open Access Journals (Sweden)

    José de Jesús Rubio

    2014-01-01

    Full Text Available The trajectory tracking problem of a proton exchange membrane (PEM fuel cell is considered. To solve this problem, an optimal controller is proposed. The optimal technique has the objective that the system states should reach the desired trajectories while the inputs are minimized. The proposed controller uses the Hamilton-Jacobi-Bellman method where its Riccati equation is considered as an adaptive function. The effectiveness of the proposed technique is verified by two simulations.

  18. HPV16-associated tumours: Therapy of surgical minimal residual disease with dendritic cell-based vaccines

    Czech Academy of Sciences Publication Activity Database

    Reiniš, Milan; Indrová, Marie; Mendoza, Luis; Mikyšková, Romana; Bieblová, Jana; Bubeník, Jan; Šímová, Jana

    2004-01-01

    Roč. 25, č. 4 (2004), s. 1165-1170. ISSN 1019-6439 R&D Projects: GA MZd NC7148; GA ČR GA301/04/0492; GA ČR GA301/01/0985; GA AV ČR IAA5052203 Institutional research plan: CEZ:AV0Z5052915 Keywords : HPV16 * minimal residual tumour disease * dendritic cells Subject RIV: EC - Immunology Impact factor: 3.056, year: 2004

  19. Fuel cells in shipping : higher capital costs and reduced flexibility

    OpenAIRE

    Sødal, Sigbjørn

    2003-01-01

    This paper discusses some main economic characteristics of fuel cell power production technology applied to shipping. Whenever competitive fuel cell systems enter the market, they are likely to have higher capital costs and lower operating costs than systems based on traditional combustion technology. Implications of the difference are investigated with respect to investment flexibility by the use of a real options model of ship investment, lay-up and scrapping decisions under freight rate un...

  20. Modulation of Neural Network Activity through Single Cell Ablation: An in Vitro Model of Minimally Invasive Neurosurgery.

    Science.gov (United States)

    Soloperto, Alessandro; Bisio, Marta; Palazzolo, Gemma; Chiappalone, Michela; Bonifazi, Paolo; Difato, Francesco

    2016-01-01

    The technological advancement of optical approaches, and the growth of their applications in neuroscience, has allowed investigations of the physio-pathology of neural networks at a single cell level. Therefore, better understanding the role of single neurons in the onset and progression of neurodegenerative conditions has resulted in a strong demand for surgical tools operating with single cell resolution. Optical systems already provide subcellular resolution to monitor and manipulate living tissues, and thus allow understanding the potentiality of surgery actuated at single cell level. In the present work, we report an in vitro experimental model of minimally invasive surgery applied on neuronal cultures expressing a genetically encoded calcium sensor. The experimental protocol entails the continuous monitoring of the network activity before and after the ablation of a single neuron, to provide a robust evaluation of the induced changes in the network activity. We report that in subpopulations of about 1000 neurons, even the ablation of a single unit produces a reduction of the overall network activity. The reported protocol represents a simple and cost effective model to study the efficacy of single-cell surgery, and it could represent a test-bed to study surgical procedures circumventing the abrupt and complete tissue removal in pathological conditions. PMID:27527143

  1. MR monitoring of minimally invasive delivery of mesenchymal stem cells into the porcine intervertebral disc.

    Directory of Open Access Journals (Sweden)

    Monika Barczewska

    Full Text Available PURPOSE: Bone marrow stem cell therapy is a new, attractive therapeutic approach for treatment of intervertebral disc (IVD degeneration; however, leakage and backflow of transplanted cells into the structures surrounding the disc may lead to the formation of undesirable osteophytes. The purpose of this study was to develop a technique for minimally invasive and accurate delivery of stem cells. METHODS: Porcine mesenchymal stem cells (MSCs were labeled with superparamagnetic iron oxide nanoparticles (SPIO, Molday ION rhodamine and first injected into the explanted swine lumbar IVD, followed by ex vivo 3T MRI. After having determined sufficient sensitivity, IVD degeneration was then induced in swine (n=3 by laser-evaporation. 3 x 10(6 SPIO-labeled cells embedded within hydrogel were injected in 2 doses using a transcutaneous cannula and an epidural anesthesia catheter. T2-weighted MR images were obtained at 3T before and immediately after cell infusion. Two weeks after injection, histological examination was performed for detection of transplanted cells. RESULTS: MSCs were efficiently labeled with Molday ION rhodamine. Cells could be readily detected in the injected vertebral tissue explants as distinct hypointensities with sufficient sensitivity. MR monitoring indicated that the MSCs were successfully delivered into the IVD in vivo, which was confirmed by iron-positive Prussian Blue staining of the tissue within the IVD. CONCLUSION: We have developed a technique for non-invasive monitoring of minimally invasive stem delivery into the IVD at 3T. By using a large animal model mimicking the anatomy of IVD in humans, the present results indicate that this procedure may be clinically feasible.

  2. COST OF HEMATOPOIETIC STEM CELL TRANSPLANTATION IN INDIA

    Directory of Open Access Journals (Sweden)

    Sanjeev Kumar Sharma

    2014-06-01

    Full Text Available Hematopoietic stem cell transplantation (HSCT is the definite cure for many hematological diseases. With the increasing indications for HSCT and its relatively low cost in Indian subcontinent, an increasing number of patients are opting for this procedure. We retrospectively analyzed the cost of one hundred sixty two HSCTs done at our center in the last three years. The median cost of autologous transplant was INR 7,52,294 (USD, $ 12,500 (range INR 6,19,850-14,17,212 and the median cost of allogenic transplant was INR 10,74,881 ($18,000 (range INR 6,49,944-23,82,227. The cost of HSCT is cheaper here compared to that in developed countries and success rates are nearly equivalent. The major factors contributing to the cost are related to the complications post-transplant mainly infections and graft versus host disease, which are also the reasons for the increased stay in the hospital.

  3. Silver nanoparticles do not influence stem cell differentiation but cause minimal toxicity

    Science.gov (United States)

    Samberg, Meghan E; Loboa, Elizabeth G; Oldenburg, Steven J; Monteiro-Riviere, Nancy A

    2012-01-01

    Aims To evaluate the toxicity and cellular uptake of both undifferentiated and differentiated human adipose-derived stem cells (hASCs) exposed to silver nanoparticles (Ag-NPs), and to assess their effect on hASC differentiation. Materials & methods hASC were exposed to 10- or 20-nm Ag-NPs at concentrations of 0.1, 1.0, 10.0, 50.0 and 100.0 μg/ml either before or after differentiation down the adipogenic or osteogenic pathways. Results Exposure of hASC to either 10- or 20-nm Ag-NPs resulted in no significant cytotoxicity to hASC, and minimal dose-dependent toxicity to adipogenic and osteogenic cells at 10 μg/ml. Each of the hASC, adipogenic and osteogenic cells showed cellular uptake of both 10- and 20-nm Ag-NPs, without causing significant ultrastructural alterations. Exposure to 10- or 20-nm Ag-NPs did not influence the differentiation of the cells, and at antimicrobial concentrations of Ag-NPs resulted in a minimal decrease in viability. Conclusion The biocompatibility of Ag-NPs with both undifferentiated and differentiated hASC establishes their suitability for incorporation into tissue-engineered graft scaffolds, for the prevention of bacterial contamination upon implantation. PMID:22583572

  4. Periocular basal cell carcinoma: cost of topical immunotherapy versus estimated cost of surgical treatment

    OpenAIRE

    Erick Marcet Santiago de Macedo; Rachel Camargo Carneiro; Pedro Carlos Carricondo; Suzana Matayoshi

    2012-01-01

    PURPOSE: The objective of this study was to compare the estimated cost of clinical and surgical treatment for basl cell carcinoma of the eyelid. METHODS: This was a pilot study of 12 patients with basal cell carcinoma receiving treatment with 5% imiquimod cream at the ocular plastic surgery center, medical school University of São Paulo (HC-FMUSP, Brazil). The cost of clinical treatment was estimated based on the time of treatment and amount of medication consumed by patients in the home sett...

  5. SOLID OXIDE FUEL CELL MANUFACTURING COST MODEL: SIMULATING RELATIONSHIPS BETWEEN PERFORMANCE, MANUFACTURING, AND COST OF PRODUCTION

    Energy Technology Data Exchange (ETDEWEB)

    Eric J. Carlson; Yong Yang; Chandler Fulton

    2004-04-20

    The successful commercialization of fuel cells will depend on the achievement of competitive system costs and efficiencies. System cost directly impacts the capital equipment component of cost of electricity (COE) and is a major contributor to the O and M component. The replacement costs for equipment (also heavily influenced by stack life) is generally a major contributor to O and M costs. In this project, they worked with the SECA industrial teams to estimate the impact of general manufacturing issues of interest on stack cost using an activities-based cost model for anode-supported planar SOFC stacks with metallic interconnects. An earlier model developed for NETL for anode supported planar SOFCs was enhanced by a linkage to a performance/thermal/mechanical model, by addition of Quality Control steps to the process flow with specific characterization methods, and by assessment of economies of scale. The 3-dimensional adiabatic performance model was used to calculate the average power density for the assumed geometry and operating conditions (i.e., inlet and exhaust temperatures, utilization, and fuel composition) based on publicly available polarizations curves. The SECA team provided guidance on what manufacturing and design issues should be assessed in this Phase I demonstration of cost modeling capabilities. They considered the impact of the following parameters on yield and cost: layer thickness (i.e., anode, electrolyte, and cathode) on cost and stress levels, statistical nature of ceramic material failure on yield, and Quality Control steps and strategies. In this demonstration of the capabilities of the linked model, only the active stack (i.e., anode, electrolyte, and cathode) and interconnect materials were included in the analysis. Factory costs are presented on an area and kilowatt basis to allow developers to extrapolate to their level of performance, stack design, materials, seal and system configurations, and internal corporate overheads and margin

  6. Low Cost PEM Fuel Cell Metal Bipolar Plates

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Conghua [TreadStone Technologies, Inc.

    2013-05-30

    Bipolar plate is an important component in fuel cell stacks and accounts for more than 75% of stack weight and volume. The technology development of metal bipolar plates can effectively reduce the fuel cells stack weight and volume over 50%. The challenge is the metal plate corrosion protection at low cost for the broad commercial applications. This project is aimed to develop innovative technological solutions to overcome the corrosion barrier of low cost metal plates. The feasibility of has been demonstrated and patented (US Patent 7,309,540). The plan is to further reduce the cost, and scale up the technology. The project is built on three pillars: 1) robust experimental evidence demonstrating the feasibility of our technology, 2) a team that consists of industrial leaders in fuel cell stack application, design, and manufactures; 3) a low-risk, significant-milestone driven program that proves the feasibility of meeting program objectives The implementation of this project will reduce the fuel cell stack metal bipolar separator plate cost which accounts 15-21% of the overall stack cost. It will contribute to the market adoption of fuel cell technologies. In addition, this corrosion protection technology can be used similar energy devices, such as batteries and electrolyzers. Therefore, the success of the project will be benefit in broad markets.

  7. Minimal model for spontaneous cell polarization and edge activity in oscillating, rotating and migrating cells

    Science.gov (United States)

    Raynaud, Franck; Ambühl, Mark E.; Gabella, Chiara; Bornert, Alicia; Sbalzarini, Ivo F.; Meister, Jean-Jacques; Verkhovsky, Alexander B.

    2016-04-01

    How cells break symmetry and organize activity at their edges to move directionally is a fundamental question in cell biology. Physical models of cell motility commonly incorporate gradients of regulatory proteins and/or feedback from the motion itself to describe the polarization of this edge activity. These approaches, however, fail to explain cell behaviour before the onset of polarization. We use polarizing and moving fish epidermal cells as a model system to bridge the gap between cell behaviours before and after polarization. Our analysis suggests a novel and simple principle of self-organizing cell activity, in which local cell-edge dynamics depends on the distance from the cell centre, but not on the orientation with respect to the front-back axis. We validate this principle with a stochastic model that faithfully reproduces a range of cell-migration behaviours. Our findings indicate that spontaneous polarization, persistent motion and cell shape are emergent properties of the local cell-edge dynamics controlled by the distance from the cell centre.

  8. Cost-effectiveness of minimal interventional procedures for chronic mechanical low back pain: design of four randomised controlled trials with an economic evaluation

    Directory of Open Access Journals (Sweden)

    Maas Esther T

    2012-12-01

    Full Text Available Abstract Background Minimal interventional procedures are frequently applied in patients with mechanical low back pain which is defined as pain presumably resulting from single sources: facet, disc, sacroiliac joint or a combination of these. Usually, these minimal interventional procedures are an integral part of a multidisciplinary pain programme. A recent systematic review issued by the Dutch Health Insurance Council showed that the effectiveness of these procedures for the total group of patients with chronic low back pain is yet unclear and cost-effectiveness unknown. The aim of the study is to evaluate whether a multidisciplinary pain programme with minimal interventional procedures is cost-effective compared to the multidisciplinary pain programme alone for patients with chronic mechanical low back pain who did not respond to conservative primary care and were referred to a pain clinic. Methods All patients with chronic low back pain who are referred to one of the 13 participating pain clinics will be asked to participate in an observational study. Patients with a suspected diagnosis of facet, disc or sacroiliac joint problems will receive a diagnostic block to confirm this diagnosis. If confirmed, they will be asked to participate in a Randomized Controlled Trial (RCT. For each single source a separate RCT will be conducted. Patients with a combination of facet, disc or sacroiliac joint problems will be invited for participation in a RCT as well. An economic evaluation from a societal perspective will be performed alongside these four RCTs. Patients will complete questionnaires at baseline, 3 and 6 weeks, 3, 6, 9 and 12 months after start of the treatment. Costs will be collected using self-completed cost questionnaires. Discussion No trials are yet available which have evaluated the cost-effectiveness of minimal interventional procedures in patients with chronic mechanical low back pain, which emphasizes the importance of this study

  9. Comparison of the costs of nonoperative care to minimally invasive surgery for sacroiliac joint disruption and degenerative sacroiliitis in a United States Medicare population: potential economic implications of a new minimally-invasive technology

    Directory of Open Access Journals (Sweden)

    Ackerman SJ

    2013-11-01

    Full Text Available Stacey J Ackerman1, David W Polly Jr2, Tyler Knight3, Karen Schneider4, Tim Holt5, John Cummings61Covance Market Access Services Inc, San Diego, CA, USA; 2University of Minnesota, Orthopaedic Surgery, Minneapolis, MN, USA; 3Covance Market Access Services Inc, Gaithersburg, MD, USA; 4Covance Market Access Services Inc, Sydney, NSW, Australia; 5Montgomery Spine Center, Orthopaedic Surgery, Montgomery, AL, USA; 6Community Health Network, Neurosurgery, Indianapolis, IN, USAIntroduction: The economic burden associated with the treatment of low back pain (LBP in the United States is significant. LBP caused by sacroiliac (SI joint disruption/degenerative sacroiliitis is most commonly treated with nonoperative care and/or open SI joint surgery. New and effective minimally invasive surgery (MIS options may offer potential cost savings to Medicare.Methods: An economic model was developed to compare the costs of MIS treatment to nonoperative care for the treatment of SI joint disruption in the hospital inpatient setting in the US Medicare population. Lifetime cost savings (2012 US dollars were estimated from the published literature and claims data. Costs included treatment, follow-up, diagnostic testing, and retail pharmacy pain medication. Costs of SI joint disruption patients managed with nonoperative care were estimated from the 2005–2010 Medicare 5% Standard Analytic Files using primary International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM diagnosis codes 720.2, 724.6, 739.4, 846.9, or 847.3. MIS fusion hospitalization cost was based on Diagnosis Related Group (DRG payments of $46,700 (with major complications - DRG 459 and $27,800 (without major complications - DRG 460, weighted assuming 3.8% of patients have complications. MIS fusion professional fee was determined from the 2012 Medicare payment for Current Procedural Terminology code 27280, with an 82% fusion success rate and 1.8% revision rate. Outcomes were

  10. Quantum processes in 8-Oxo-Guanine-Ru(bipyridine)32+ photosynthetic systems of artificial minimal cells

    Science.gov (United States)

    Tamulis, Arvydas; Grigalavicius, Mantas; Krisciukaitis, Sarunas; Medzevicius, Giedrius

    2011-06-01

    Density functional theory methods were used to investigate various self-assembled photoactive bioorganic systems of interest for artificial minimal cells. The cell systems studied are based on nucleotides or their compounds and consisted of up to 123 atoms (not including the associated water or methanol solvent shells) and are up to 2.5 nm in diameter. The electron correlation interactions responsible for the weak hydrogen and Van derWaals chemical bonds increase due to the addition of a polar solvent (water or methanol). The precursor fatty acid molecules of the system also play a critical role in the quantum mechanical interaction based self-assembly of the photosynthetic center and the functioning of the photosynthetic processes of the artificial minimal cells. The distances between the separated sensitizer, fatty acid precursor, and methanol molecules are comparable to Van derWaals and hydrogen bonding radii. As a result the associated electron correlation interactions compress the overall system, resulting in an even smaller gap between the highest occupied molecular orbital (HOMO), and lowest unoccupied molecular orbital (LUMO) electron energy levels and photoexcited electron tunnelling occurs from the sensitizer (either Ru(bpy)32+ or [Ru(bpy)2(4-Bu-4'-Me-2,2'-bpy)]2++ derivatives) to the precursor fatty acid molecules (notation used: Me = methyl; Bu = butyl; bpy = bipyridine). The shift of the absorption spectrum to the red for the artificial protocell photosynthetic centers might be considered as the measure of the complexity of these systems.

  11. Selective apoptosis induction in MCF-7 cell line by truncated minimal functional region of Apoptin

    International Nuclear Information System (INIS)

    Chicken Anemia Virus (CAV) VP3 protein (also known as Apoptin), a basic and proline-rich protein has a unique capability in inducing apoptosis in cancer cells but not in normal cells. Five truncated Apoptin proteins were analyzed to determine their selective ability to migrate into the nucleus of human breast adenocarcinoma MCF-7 cells for inducing apoptosis. For identification of the minimal selective domain for apoptosis, the wild-type Apoptin gene had been reconstructed by PCR to generate segmental deletions at the N’ terminal and linked with nuclear localization sites (NLS1 and NLS2). All the constructs were fused with maltose-binding protein gene and individually expressed by in vitro Rapid Translation System. Standardized dose of proteins were delivered into human breast adenocarcinoma MCF-7 cells and control human liver Chang cells by cytoplasmic microinjection, and subsequently observed for selective apoptosis effect. Three of the truncated Apoptin proteins with N-terminal deletions spanning amino acid 32–83 retained the cancer selective nature of wild-type Apoptin. The proteins were successfully translocated to the nucleus of MCF-7 cells initiating apoptosis, whereas non-toxic cytoplasmic retention was observed in normal Chang cells. Whilst these truncated proteins retained the tumour-specific death effector ability, the specificity for MCF-7 cells was lost in two other truncated proteins that harbor deletions at amino acid 1–31. The detection of apoptosing normal Chang cells and MCF-7 cells upon cytoplasmic microinjection of these proteins implicated a loss in Apoptin’s signature targeting activity. Therefore, the critical stretch spanning amino acid 1–31 at the upstream of a known hydrophobic leucine-rich stretch (LRS) was strongly suggested as one of the prerequisite region in Apoptin for cancer targeting. Identification of this selective domain provides a platform for developing small targets to facilitating carrier-mediated-transport across

  12. Minimal residual disease in breast cancer: an overview of circulating and disseminated tumour cells.

    Science.gov (United States)

    Tachtsidis, A; McInnes, L M; Jacobsen, N; Thompson, E W; Saunders, C M

    2016-08-01

    Within the field of cancer research, focus on the study of minimal residual disease (MRD) in the context of carcinoma has grown exponentially over the past several years. MRD encompasses circulating tumour cells (CTCs)-cancer cells on the move via the circulatory or lymphatic system, disseminated tumour cells (DTCs)-cancer cells which have escaped into a distant site (most studies have focused on bone marrow), and resistant cancer cells surviving therapy-be they local or distant, all of which may ultimately give rise to local relapse or overt metastasis. Initial studies simply recorded the presence and number of CTCs and DTCs; however recent advances are allowing assessment of the relationship between their persistence, patient prognosis and the biological properties of MRD, leading to a better understanding of the metastatic process. Technological developments for the isolation and analysis of circulating and disseminated tumour cells continue to emerge, creating new opportunities to monitor disease progression and perhaps alter disease outcome. This review outlines our knowledge to date on both measurement and categorisation of MRD in the form of CTCs and DTCs with respect to how this relates to cancer outcomes, and the hurdles and future of research into both CTCs and DTCs. PMID:27189371

  13. β-Catenin transcriptional activity is minimal in canine osteosarcoma and its targeted inhibition results in minimal changes to cell line behaviour.

    Science.gov (United States)

    Piskun, Caroline M; Stein, Timothy J

    2016-06-01

    Canine osteosarcoma (OS) is an aggressive malignancy associated with poor outcomes. Therapeutic improvements are likely to develop from an improved understanding of signalling pathways contributing to OS development and progression. The Wnt signalling pathway is of interest for its role in osteoblast differentiation, its dysregulation in numerous cancer types, and the relative frequency of cytoplasmic accumulation of β-catenin in canine OS. This study aimed to determine the biological impact of inhibiting canonical Wnt signalling in canine OS, by utilizing either β-catenin siRNA or a dominant-negative T-cell factor (TCF) construct. There were no consistent, significant changes in cell line behaviour with either method compared to parental cell lines. Interestingly, β-catenin transcriptional activity was three-fold higher in normal canine primary osteoblasts compared to canine OS cell lines. These results suggest canonical Wnt signalling is minimally active in canine OS and its targeted inhibition is not a relevant therapeutic strategy. PMID:24256430

  14. Periocular basal cell carcinoma: cost of topical immunotherapy versus estimated cost of surgical treatment

    Directory of Open Access Journals (Sweden)

    Erick Marcet Santiago de Macedo

    2012-06-01

    Full Text Available PURPOSE: The objective of this study was to compare the estimated cost of clinical and surgical treatment for basl cell carcinoma of the eyelid. METHODS: This was a pilot study of 12 patients with basal cell carcinoma receiving treatment with 5% imiquimod cream at the ocular plastic surgery center, medical school University of São Paulo (HC-FMUSP, Brazil. The cost of clinical treatment was estimated based on the time of treatment and amount of medication consumed by patients in the home setting. The cost of surgical treatment was estimated by ophthalmologists with experience in reconstructive plastic surgery based on analysis of images of the same patients. Surgeons responded to a questionnaire with four questions about surgical technique, surgical materials required, estimated duration of surgery and type of anesthesia. RESULTS: Immunotherapy lasted from 8 to 12 weeks.All patients reported each coldstored sachet with 5% imiquimod cream lasted 3 days.According to the institution, a box with 12 sachets costs BRL 480.00. Patients required 1.58-3.11 boxes for complete treatment, corresponding to a total cost of BRL 758.401,492.80. Based on image analysis, surgeons evaluated surgery would require 1-3 hours. The estimated cost of surgery room and staff was BRL 263.00, to which the cost of supplies was added. Thus, the total cost of surgical treatment was BRL 272.61-864.82. On the average, immunotherapy was 57,64% more costly than surgical treatment. CONCLUSIONS: Malignant eyelid tumors are a common finding in clinical ophthalmology. Surgery is still the treatment of choice at our institution, but immunotherapy with 5% imiquimod cream may be indicated for patients with multiple lesions or high surgical risk and for patients declining surgery for reasons of fear or esthetic concerns.The ability to estimate costs related to the treatment of malignant eyelid tumors is an important aid in the financial planning of health care institutions. Further

  15. Inkjet-bioprinted acrylated peptides and PEG hydrogel with human mesenchymal stem cells promote robust bone and cartilage formation with minimal printhead clogging.

    Science.gov (United States)

    Gao, Guifang; Yonezawa, Tomo; Hubbell, Karen; Dai, Guohao; Cui, Xiaofeng

    2015-10-01

    Inkjet bioprinting is one of the most promising additive manufacturing approaches for tissue fabrication with the advantages of high speed, high resolution, and low cost. The limitation of this technology is the potential damage to the printed cells and frequent clogging of the printhead. Here we developed acrylated peptides and co-printed with acrylated poly(ethylene glycol) (PEG) hydrogel with simultaneous photopolymerization. At the same time, the bone marrow-derived human mesenchymal stem cells (hMSCs) were precisely printed during the scaffold fabrication process so the cells were delivered simultaneously with minimal UV exposure. The multiple steps of scaffold synthesis and cell encapsulation were successfully combined into one single step using bioprinting. The resulted peptide-conjugated PEG scaffold demonstrated excellent biocompatibility, with a cell viability of 87.9 ± 5.3%. Nozzle clogging was minimized due to the low viscosity of the PEG polymer. With osteogenic and chondrogenic differentiation, the bioprinted bone and cartilage tissue demonstrated excellent mineral and cartilage matrix deposition, as well as significantly increased mechanical properties. Strikingly, the bioprinted PEG-peptide scaffold dramatically inhibited hMSC hypertrophy during chondrogenic differentiation. Collectively, bioprinted PEG-peptide scaffold and hMSCs significantly enhanced osteogenic and chondrogenic differentiation for robust bone and cartilage formation with minimal printhead clogging. PMID:25641582

  16. Cost-minimization analysis of the direct costs of TPE and IVIg in the treatment of Guillain-Barré syndrome

    Directory of Open Access Journals (Sweden)

    Chainani Ashok

    2011-05-01

    Full Text Available Abstract Background Controlled trials have found therapeutic plasma exchange (TPE and intravenous immunoglobulin (IVIg infusion therapy to be equally efficacious in treating Guillain-Barré syndrome (GBS. Due to increases in the price of IVIg compared to human serum albumin (HSA, used as a replacement fluid in TPE, we examined direct hospital-level expenditures for TPE and IVIg for meaningful cost-differences between these treatments. Methods Using financial data from our two institutions, hospital cost profiles for IVIg and 5% albumin were established. Reimbursement amounts were obtained from publicly available Medicare data resources to determine payment rates for TPE, non-tunneled central catheter line placement, and drug infusion therapy. A model was developed which allows hospitals to input cost and reimbursement amounts for both IVIg and TPE with HSA that results in real-time valuations of these interventions. Results The direct cost of five IVIg infusion sessions totaling 2.0 grams per kilogram (g/kg body weight was $10,329.85 compared to a series of five TPE procedures, which had direct costs of $4,638.16. Conclusions In GBS patients, direct costs of IVIg therapy are more than twice that of TPE. Given equivalent efficacy and similar severity and frequencies of adverse events, TPE appears to be a less expensive first-line therapy option for treatment of patients with GBS.

  17. Accessible bioprinting: adaptation of a low-cost 3D-printer for precise cell placement and stem cell differentiation.

    Science.gov (United States)

    Reid, John A; Mollica, Peter A; Johnson, Garett D; Ogle, Roy C; Bruno, Robert D; Sachs, Patrick C

    2016-01-01

    The precision and repeatability offered by computer-aided design and computer-numerically controlled techniques in biofabrication processes is quickly becoming an industry standard. However, many hurdles still exist before these techniques can be used in research laboratories for cellular and molecular biology applications. Extrusion-based bioprinting systems have been characterized by high development costs, injector clogging, difficulty achieving small cell number deposits, decreased cell viability, and altered cell function post-printing. To circumvent the high-price barrier to entry of conventional bioprinters, we designed and 3D printed components for the adaptation of an inexpensive 'off-the-shelf' commercially available 3D printer. We also demonstrate via goal based computer simulations that the needle geometries of conventional commercially standardized, 'luer-lock' syringe-needle systems cause many of the issues plaguing conventional bioprinters. To address these performance limitations we optimized flow within several microneedle geometries, which revealed a short tapered injector design with minimal cylindrical needle length was ideal to minimize cell strain and accretion. We then experimentally quantified these geometries using pulled glass microcapillary pipettes and our modified, low-cost 3D printer. This systems performance validated our models exhibiting: reduced clogging, single cell print resolution, and maintenance of cell viability without the use of a sacrificial vehicle. Using this system we show the successful printing of human induced pluripotent stem cells (hiPSCs) into Geltrex and note their retention of a pluripotent state 7 d post printing. We also show embryoid body differentiation of hiPSC by injection into differentiation conducive environments, wherein we observed continuous growth, emergence of various evaginations, and post-printing gene expression indicative of the presence of all three germ layers. These data demonstrate an

  18. Metal-air cells comprising collapsible foam members and means for minimizing internal pressure buildup

    Science.gov (United States)

    Woodruff, Glenn (Inventor); Putt, Ronald A. (Inventor)

    1994-01-01

    This invention provides a prismatic zinc-air cell including, in general, a prismatic container having therein an air cathode, a separator and a zinc anode. The container has one or more oxygen access openings, and the air cathode is disposed in the container in gaseous communication with the oxygen access openings so as to allow access of oxygen to the cathode. The separator has a first side in electrolytic communication with the air cathode and a second side in electrolytic communication with the zinc anode. The separator isolates the cathode and the zinc anode from direct electrical contact and allows passage of electrolyte therebetween. An expansion chamber adjacent to the zinc anode is provided which accommodates expansion of the zinc anode during discharge of the cell. A suitable collapsible foam member generally occupies the expansion space, providing sufficient resistance tending to oppose movement of the zinc anode away from the separator while collapsing upon expansion of the zinc anode during discharge of the cell. One or more vent openings disposed in the container are in gaseous communication with the expansion space, functioning to satisfactorily minimize the pressure buildup within the container by venting gasses expelled as the foam collapses during cell discharge.

  19. Multiple travelling-wave solutions in a minimal model for cell motility

    KAUST Repository

    Kimpton, L. S.

    2012-07-11

    Two-phase flow models have been used previously to model cell motility. In order to reduce the complexity inherent with describing the many physical processes, we formulate a minimal model. Here we demonstrate that even the simplest 1D, two-phase, poroviscous, reactive flow model displays various types of behaviour relevant to cell crawling. We present stability analyses that show that an asymmetric perturbation is required to cause a spatially uniform, stationary strip of cytoplasm to move, which is relevant to cell polarization. Our numerical simulations identify qualitatively distinct families of travellingwave solutions that coexist at certain parameter values. Within each family, the crawling speed of the strip has a bell-shaped dependence on the adhesion strength. The model captures the experimentally observed behaviour that cells crawl quickest at intermediate adhesion strengths, when the substrate is neither too sticky nor too slippy. © The Author 2012. Published by Oxford University Press on behalf of the Institute of Mathematics and its Applications. All rights reserved.

  20. Minimization of Handoff Failure by Introducing a New Cell Coverage Area in the Handoff Region

    Directory of Open Access Journals (Sweden)

    Debabrata Sarddar

    2011-05-01

    Full Text Available Presently, IEEE 802.11 based wireless local area networks (WLAN have been widely deployed for business and personal applications. The main issue regarding wireless network technology is handoff or hand over management, especially in urban areas, due to the limited coverage of access points (APs or base stations (BS. When a mobile station (MS moves outside the range of its current access point (AP it needs to perform a link layer handover. This causes data loss and interruption in communication. Many people have applied efficient location management techniques in the literature of next generation wireless system (NGWS. However, seamless handover management still remains an open matter of research. Here we propose a method to minimize the handoff failure probability by effectively placing a wireless local area network (WLAN AP in the handoff region between two neighboring cells. The WLAN coverage, on one hand, provides an additional coverage in the low signal strength region, and on the other hand, relieves the congestion in the cellular network. Moreover, we perform the channel scanning (required for horizontal handover between the two base stations within the WLAN coverage area, thus minimizing the handoff failure due to scanning delay.

  1. A New Optimization Model for Distribution Siting and Sizing in Unbalanced Three-phase Networks for Loss and Cost Minimization

    Directory of Open Access Journals (Sweden)

    Farzaneh Yazdani

    2014-06-01

    Full Text Available Since distribution substations connect transmission lines and distribution system, planning these substations is a very important step in scheduling process of power system and optimal placement of distribution transformers for reducing the involved loss is of concern. In this paper a new model is [proposed for solving optimal substation planning of distribution networks. In the objective function, we have included both capital and operation (loss costs. The optimization problem is solved by genetic algorithm (GA. In order to evaluate the effects of load imbalance in low-voltage system, a group of balanced one-phase and three-phase and imbalanced three-phase in 4-wire system are used. As a case study, the optimization model is tested on the 33-bus system. Simulation results show that the total cost is reduced by balancing the load of different phases. Also, the results confirm a 48 % reduction in loss and an 11 % reduction in costs of the network planning. Moreover influence of energy cost change and load change on distribution network planning is evaluated by investigating on 33-bus system.

  2. Convergence Analysis of Distributed Control for Operation Cost Minimization of Droop Controlled DC Microgrid Based on Multiagent

    DEFF Research Database (Denmark)

    Li, Chendan; Quintero, Juan Carlos Vasquez; Guerrero, Josep M.

    2016-01-01

    collective decision for the whole system is made by proposed incremental cost consensus, and only nearest-neighbor communication is needed. The convergence characteristics of the consensus algorithm are analyzed considering different communication topologies and control parameters. Case studies verified the...... proposed method by comparing it without traditional methods. The robustness of system is tested under different communication latency and plug and play operation....

  3. NLP model of a LiBr–H2O absorption refrigeration system for the minimization of the annual operating cost

    International Nuclear Information System (INIS)

    In this paper the optimization of a LiBr–H2O absorption refrigeration system with the annual operating cost as the objective function to be minimized is presented. The optimization problem is established as a Non-Linear Programming (NLP) model allowing a formulation of the problem in a simple and structured way, and reducing the typical complexity of the thermal systems. The model is composed of three main parts: the thermodynamic model based on the exergy concept including also the proper formulation for the thermodynamic properties of the LiBr–H2O mixture, the second is the economic model and the third part composed by inequality constraints. The solution of the model is obtained using the CONOPT solver suitable for NLP problems (code is available on request). The results show the values of the decision variables that minimize the annual cost under the set of assumptions considered in the model and agree well with those reported in other works using different optimization approaches. - Highlights: ► The optimization of an ARS is presented using the annual operating cost as the objective function. ► The problem is established as an NLP model allowing a formulation in a simple and structured way. ► Several formulations for the thermodynamic properties were tested to implement the simpler ones. ► The results obtained agree well with those reported in the work being in comparison.

  4. A New Optimization Model for Distribution Siting and Sizing in Unbalanced Three-phase Networks for Loss and Cost Minimization

    OpenAIRE

    Farzaneh Yazdani; Seyyed Mehdy Hosseini; Taghi Barforuoshi

    2014-01-01

    Since distribution substations connect transmission lines and distribution system, planning these substations is a very important step in scheduling process of power system and optimal placement of distribution transformers for reducing the involved loss is of concern. In this paper a new model is [proposed for solving optimal substation planning of distribution networks. In the objective function, we have included both capital and operation (loss) costs. The optimization problem is solved by...

  5. Simplified Model for the Activated Sludge System: WWTP Cost Minimization via an Augmented Lagrangian Pattern Search Method

    Science.gov (United States)

    Espírito Santo, Isabel A. C. P.; Fernandes, Edite M. G. P.

    2010-09-01

    This paper aims to validate a proposed simplified model of the activated sludge system. A comparison between the classical and simplified models is made. The optimization of the operational and investment costs in order to achieve the best design is conducted using an augmented Lagrangian pattern search based algorithm. The results are similar in both models and reinforced that the simplified model is a good approach.

  6. Local cost minimization in ant transport networks: from small-scale data to large-scale trade-offs.

    Science.gov (United States)

    Bottinelli, A; van Wilgenburg, E; Sumpter, D J T; Latty, T

    2015-11-01

    Transport networks distribute resources and information in many human and biological systems. Their construction requires optimization and balance of conflicting criteria such as robustness against disruptions, transport efficiency and building cost. The colonies of the polydomous Australian meat ant Iridomyrmex purpureus are a striking example of such a decentralized network, consisting of trails that connect spatially separated nests. Here we study the rules that underlie network construction in these ants. We find that a simple model of network growth, which we call the minimum linking model (MLM), is sufficient to explain the growth of real ant colonies. For larger networks, the MLM shows a qualitative similarity with a Euclidean minimum spanning tree, prioritizing cost and efficiency over robustness. We introduce a variant of our model to show that a balance between cost, efficiency and robustness can be also reproduced at larger scales than ant colonies. Remarkably, such a balance is influenced by a parameter reflecting the specific features of the modelled transport system. The extended MLM could thus be a suitable source of inspiration for the construction of cheap and efficient transport networks with non-zero robustness, suggesting possible applications in the design of human-made networks. PMID:26490633

  7. Seam-line determination for image mosaicking: A technique minimizing the maximum local mismatch and the global cost

    Science.gov (United States)

    Chon, Jaechoon; Kim, Hyongsuk; Lin, Chun-Shin

    2010-01-01

    This paper presents a novel algorithm that selects seam-lines for mosaicking image patches. This technique uses Dijkstra's algorithm to find a seam-line with the minimal objective function. Since a segment of seam-line with significant mismatch, even if it is short, is more visible than a lengthy one with small differences, a direct summation of the mismatch scores is inadequate. Limiting the level of the maximum difference along a seam-line should be part of the objective in the seam-line selection process. Our technique first determines this desired level of maximum difference, then applies Dijkstra's algorithm to find the best seam-line. A quantitative measure to evaluate a seam-line is proposed. The measure is defined as the sum of a fixed number of top mismatch scores. The proposed algorithm is compared with other techniques quantitatively and visually about various types of images.

  8. A Low Cost Weather Balloon Borne Solar Cell Calibration Payload

    Science.gov (United States)

    Snyder, David B.; Wolford, David S.

    2012-01-01

    Calibration of standard sets of solar cell sub-cells is an important step to laboratory verification of on-orbit performance of new solar cell technologies. This paper, looks at the potential capabilities of a lightweight weather balloon payload for solar cell calibration. A 1500 gr latex weather balloon can lift a 2.7 kg payload to over 100,000 ft altitude, above 99% of the atmosphere. Data taken between atmospheric pressures of about 30 to 15 mbar may be extrapolated via the Langley Plot method to 0 mbar, i.e. AMO. This extrapolation, in principle, can have better than 0.1 % error. The launch costs of such a payload arc significantly less than the much larger, higher altitude balloons, or the manned flight facility. The low cost enables a risk tolerant approach to payload development. Demonstration of 1% standard deviation flight-to-flight variation is the goal of this project. This paper describes the initial concept of solar cell calibration payload, and reports initial test flight results. .

  9. Irreversibility of T-Cell Specification: Insights from Computational Modelling of a Minimal Network Architecture

    Science.gov (United States)

    Manesso, Erica; Kueh, Hao Yuan; Freedman, George; Rothenberg, Ellen V.

    2016-01-01

    Background/Objectives A cascade of gene activations under the control of Notch signalling is required during T-cell specification, when T-cell precursors gradually lose the potential to undertake other fates and become fully committed to the T-cell lineage. We elucidate how the gene/protein dynamics for a core transcriptional module governs this important process by computational means. Methods We first assembled existing knowledge about transcription factors known to be important for T-cell specification to form a minimal core module consisting of TCF-1, GATA-3, BCL11B, and PU.1 aiming at dynamical modeling. Model architecture was based on published experimental measurements of the effects on each factor when each of the others is perturbed. While several studies provided gene expression measurements at different stages of T-cell development, pure time series are not available, thus precluding a straightforward study of the dynamical interactions among these genes. We therefore translate stage dependent data into time series. A feed-forward motif with multiple positive feed-backs can account for the observed delay between BCL11B versus TCF-1 and GATA-3 activation by Notch signalling. With a novel computational approach, all 32 possible interactions among Notch signalling, TCF-1, and GATA-3 are explored by translating combinatorial logic expressions into differential equations for BCL11B production rate. Results Our analysis reveals that only 3 of 32 possible configurations, where GATA-3 works as a dimer, are able to explain not only the time delay, but very importantly, also give rise to irreversibility. The winning models explain the data within the 95% confidence region and are consistent with regard to decay rates. Conclusions This first generation model for early T-cell specification has relatively few players. Yet it explains the gradual transition into a committed state with no return. Encoding logics in a rate equation setting allows determination of

  10. Minimally invasive cell-seeded biomaterial systems for injectable/epicardial implantation in ischemic heart disease

    Directory of Open Access Journals (Sweden)

    Ravichandran R

    2012-12-01

    Full Text Available Rajeswari Ravichandran,1,2 Jayarama Reddy Venugopal,1 Subramanian Sundarrajan,1,2 Shayanti Mukherjee,1 Seeram Ramakrishna1,21Healthcare and Energy Materials Laboratory, 2Department of Mechanical Engineering, National University of Singapore, SingaporeAbstract: Myocardial infarction (MI is characterized by heart-wall thinning, myocyte slippage, and ventricular dilation. The injury to the heart-wall muscle after MI is permanent, as after an abundant cell loss the myocardial tissue lacks the intrinsic capability to regenerate. New therapeutics are required for functional improvement and regeneration of the infarcted myocardium, to overcome harmful diagnosis of patients with heart failure, and to overcome the shortage of heart donors. In the past few years, myocardial tissue engineering has emerged as a new and ambitious approach for treating MI. Several left ventricular assist devices and epicardial patches have been developed for MI. These devices and acellular/cellular cardiac patches are employed surgically and sutured to the epicardial surface of the heart, limiting the region of therapeutic benefit. An injectable system offers the potential benefit of minimally invasive release into the myocardium either to restore the injured extracellular matrix or to act as a scaffold for cell delivery. Furthermore, intramyocardial injection of biomaterials and cells has opened new opportunities to explore and also to augment the potentials of this technique to ease morbidity and mortality rates owing to heart failure. This review summarizes the growing body of literature in the field of myocardial tissue engineering, where biomaterial injection, with or without simultaneous cellular delivery, has been pursued to enhance functional and structural outcomes following MI. Additionally, this review also provides a complete outlook on the tissue-engineering therapies presently being used for myocardial regeneration, as well as some perceptivity into the possible

  11. Minimal residual disease monitoring by 8-color flow cytometry in mantle cell lymphoma: an EU-MCL and LYSA study

    Science.gov (United States)

    Cheminant, Morgane; Derrieux, Coralie; Touzart, Aurore; Schmit, Stéphanie; Grenier, Adrien; Trinquand, Amélie; Delfau-Larue, Marie-Hélène; Lhermitte, Ludovic; Thieblemont, Catherine; Ribrag, Vincent; Cheze, Stéphane; Sanhes, Laurence; Jardin, Fabrice; Lefrère, François; Delarue, Richard; Hoster, Eva; Dreyling, Martin; Asnafi, Vahid; Hermine, Olivier; Macintyre, Elizabeth

    2016-01-01

    Quantification of minimal residual disease may guide therapeutic strategies in mantle cell lymphoma. While multiparameter flow cytometry is used for diagnosis, the gold standard method for minimal residual disease analysis is real-time quantitative polymerase chain reaction (RQ-PCR). In this European Mantle Cell Lymphoma network (EU-MCL) pilot study, we compared flow cytometry with RQ-PCR for minimal residual disease detection. Of 113 patients with at least one minimal residual disease sample, RQ-PCR was applicable in 97 (86%). A total of 284 minimal residual disease samples from 61 patients were analyzed in parallel by flow cytometry and RQ-PCR. A single, 8-color, 10-antibody flow cytometry tube allowed specific minimal residual disease assessment in all patients, with a robust sensitivity of 0.01%. Using this cut-off level, the true-positive-rate of flow cytometry with respect to RQ-PCR was 80%, whereas the true-negative-rate was 92%. As expected, RQ-PCR frequently detected positivity below this 0.01% threshold, which is insufficiently sensitive for prognostic evaluation and would ideally be replaced with robust quantification down to a 0.001% (10-5) threshold. In 10 relapsing patients, the transition from negative to positive by RQ-PCR (median 22.5 months before relapse) nearly always preceded transition by flow cytometry (4.5 months), but transition to RQ-PCR positivity above 0.01% (5 months) was simultaneous. Pre-emptive rituximab treatment of 2 patients at minimal residual disease relapse allowed re-establishment of molecular and phenotypic complete remission. Flow cytometry minimal residual disease is a complementary approach to RQ-PCR and a promising tool in individual mantle cell lymphoma therapeutic management. PMID:26703963

  12. Minimal residual disease monitoring by 8-color flow cytometry in mantle cell lymphoma: an EU-MCL and LYSA study.

    Science.gov (United States)

    Cheminant, Morgane; Derrieux, Coralie; Touzart, Aurore; Schmit, Stéphanie; Grenier, Adrien; Trinquand, Amélie; Delfau-Larue, Marie-Hélène; Lhermitte, Ludovic; Thieblemont, Catherine; Ribrag, Vincent; Cheze, Stéphane; Sanhes, Laurence; Jardin, Fabrice; Lefrère, François; Delarue, Richard; Hoster, Eva; Dreyling, Martin; Asnafi, Vahid; Hermine, Olivier; Macintyre, Elizabeth

    2016-03-01

    Quantification of minimal residual disease may guide therapeutic strategies in mantle cell lymphoma. While multiparameter flow cytometry is used for diagnosis, the gold standard method for minimal residual disease analysis is real-time quantitative polymerase chain reaction (RQ-PCR). In this European Mantle Cell Lymphoma network (EU-MCL) pilot study, we compared flow cytometry with RQ-PCR for minimal residual disease detection. Of 113 patients with at least one minimal residual disease sample, RQ-PCR was applicable in 97 (86%). A total of 284 minimal residual disease samples from 61 patients were analyzed in parallel by flow cytometry and RQ-PCR. A single, 8-color, 10-antibody flow cytometry tube allowed specific minimal residual disease assessment in all patients, with a robust sensitivity of 0.01%. Using this cut-off level, the true-positive-rate of flow cytometry with respect to RQ-PCR was 80%, whereas the true-negative-rate was 92%. As expected, RQ-PCR frequently detected positivity below this 0.01% threshold, which is insufficiently sensitive for prognostic evaluation and would ideally be replaced with robust quantification down to a 0.001% (10-5) threshold. In 10 relapsing patients, the transition from negative to positive by RQ-PCR (median 22.5 months before relapse) nearly always preceded transition by flow cytometry (4.5 months), but transition to RQ-PCR positivity above 0.01% (5 months) was simultaneous. Pre-emptive rituximab treatment of 2 patients at minimal residual disease relapse allowed re-establishment of molecular and phenotypic complete remission. Flow cytometry minimal residual disease is a complementary approach to RQ-PCR and a promising tool in individual mantle cell lymphoma therapeutic management. PMID:26703963

  13. Cost minimization analysis at the Hospital Mexico in the Caja Costarricense de Seguro Social for the accommodation of patients with radiotherapy with linear accelerator: shelter vs transfers

    International Nuclear Information System (INIS)

    Patients with oncological pathology have attended daily in sessions for several weeks in the linear accelerator radiation therapy. Persons subject to this intervention have moved to the Hospital Mexico of the social security of Costa Rica, place that centralizes this treatment. The Caja Costarricense de Seguro Social (CCSS) has considered two options depending on the place of origin of users: bear the costs of commuting from the area of habitual residence, or place them temporarily in a shelter provided by the institution; the CCSS has chosen the first alternative. This research has consisted of a cost-minimization analysis between these two alternatives. The study population are patients with oncological pathology attending sessions of radiotherapy with linear accelerator at the Hospital Mexico in the first half of 2009 using ambulances of Cruz Roja Costarricense. The size of the study population is 107 persons, the total number of transferred recorded in the Fondo Rotatorio de Operaciones of Hospital Mexico is 998. Patients came from five regions and twenty areas of health according to the geographical division of the CCSS. The variables included have been: cost per day by way of transfer, which involves the distance to the radiotherapy center of Hospital Mexico and the cost of the rate at Cruz Roja ambulance per Km (326.86 colons, according to the agreement CCSS-Cruz Roja in June 2009) estimated daily cost of lodging in a shelter, and the reason daily cost of relocation / daily cost of shelter. The cost of shelter includes food and were used data from the company International Medical Suppliers S. A. as a basis for estimating the daily cost, the price fixed by the company was 65 dollars a day, and the conversion into colons exchange rate as established by the Banco Central de Costa Rica; dated April 30, 2010, the amount has been 33.542.60 colons. The reason for each area of health was given by the ratio of the average daily cost in colons by way of ambulance of

  14. Optimal Control Method for Wind Farm to Support Temporary Primary Frequency Control with Minimized Wind Energy Cost

    DEFF Research Database (Denmark)

    Wang, Haijiao; Chen, Zhe; Jiang, Quanyuan

    2015-01-01

    dispatch (TSPOD) of the WF. With TFSC, the VSWT could temporarily provide extra power to support system frequency under varying and wide-range wind speed. In the WF control centre, TSPOD optimally dispatches the frequency support power orders to the VSWTs that operate under different wind speeds, minimises...... the wind energy cost of frequency support, and satisfies the support capabilities of the VSWTs. The effectiveness of the whole control method is verified in the IEEE-RTS built in MATLABSimulink, and compared with a published de-loading method.......This study proposes an optimal control method for variable speed wind turbines (VSWTs) based wind farm (WF) to support temporary primary frequency control. This control method consists of two layers: temporary frequency support control (TFSC) of the VSWT, and temporary support power optimal...

  15. Using cathode spacers to minimize reactor size in air cathode microbial fuel cells

    KAUST Repository

    Yang, Qiao

    2012-04-01

    Scaling up microbial fuel cells (MFCs) will require more compact reactor designs. Spacers can be used to minimize the reactor size without adversely affecting performance. A single 1.5mm expanded plastic spacer (S1.5) produced a maximum power density (973±26mWm -2) that was similar to that of an MFC with the cathode exposed directly to air (no spacer). However, a very thin spacer (1.3mm) reduced power by 33%. Completely covering the air cathode with a solid plate did not eliminate power generation, indicating oxygen leakage into the reactor. The S1.5 spacer slightly increased columbic efficiencies (from 20% to 24%) as a result of reduced oxygen transfer into the system. Based on operating conditions (1000ς, CE=20%), it was estimated that 0.9Lh -1 of air would be needed for 1m 2 of cathode area suggesting active air flow may be needed for larger scale MFCs. © 2012 Elsevier Ltd.

  16. Geometric analysis of the Goldbeter minimal model for the embryonic cell cycle.

    Science.gov (United States)

    Kosiuk, Ilona; Szmolyan, Peter

    2016-04-01

    A minimal model describing the embryonic cell division cycle at the molecular level in eukaryotes is analyzed mathematically. It is known from numerical simulations that the corresponding three-dimensional system of ODEs has periodic solutions in certain parameter regimes. We prove the existence of a stable limit cycle and provide a detailed description on how the limit cycle is generated. The limit cycle corresponds to a relaxation oscillation of an auxiliary system, which is singularly perturbed and has the same orbits as the original model. The singular perturbation character of the auxiliary problem is caused by the occurrence of small Michaelis constants in the model. Essential pieces of the limit cycle of the auxiliary problem consist of segments of slow motion close to several branches of a two dimensional critical manifold which are connected by fast jumps. In addition, a new phenomenon of exchange of stability occurs at lines, where the branches of the two-dimensional critical manifold intersect. This novel type of relaxation oscillations is studied by combining standard results from geometric singular perturbation with several suitable blow-up transformations. PMID:26100376

  17. Cost Analysis of Fuel Cell Systems for Transportation Compressed Hydrogen and PEM Fuel Cell System

    Energy Technology Data Exchange (ETDEWEB)

    Eric J. Carlson

    2004-10-20

    PEMFC technology for transportation must be competitive with internal combustion engine powertrains in a number of key metrics, including performance, life, reliability, and cost. Demonstration of PEMFC cost competitiveness has its own challenges because the technology has not been applied to high volume automotive markets. The key stack materials including membranes, electrodes, bipolar plates, and gas diffusion layers have not been produced in automotive volumes to the exacting quality requirements that will be needed for high stack yields and to the evolving property specifications of high performance automotive stacks. Additionally, balance-of-plant components for air, water, and thermal management are being developed to meet the unique requirements of fuel cell systems. To address the question of whether fuel cells will be cost competitive in automotive markets, the DOE has funded this project to assess the high volume production cost of PEM fuel cell systems. In this report a historical perspective of our efforts in assessment of PEMFC cost for DOE is provided along with a more in-depth assessment of the cost of compressed hydrogen storage is provided. Additionally, the hydrogen storage costs were incorporated into a system cost update for 2004. Assessment of cost involves understanding not only material and production costs, but also critical performance metrics, i.e., stack power density and associated catalyst loadings that scale the system components. We will discuss the factors influencing the selection of the system specification (i.e., efficiency, reformate versus direct hydrogen, and power output) and how these have evolved over time. The reported costs reflect internal estimates and feedback from component developers and the car companies. Uncertainty in the cost projection was addressed through sensitivity analyses.

  18. Cell biology and genetics of minimal change disease [version 1; referees: 2 approved

    Directory of Open Access Journals (Sweden)

    Moin A. Saleem

    2016-03-01

    Full Text Available Minimal change disease (MCD is an important cause of nephrotic syndrome and is characterized by massive proteinuria and hypoalbuminemia, resulting in edema and hypercholesterolemia. The podocyte plays a key role in filtration and its disruption results in a dramatic loss of function leading to proteinuria. Immunologic disturbance has been suggested in the pathogenesis of MCD. Because of its clinical features, such as recurrent relapse/remission course, steroid response in most patients, and rare familial cases, a genetic defect has been thought to be less likely in MCD. Recent progress in whole-exome sequencing reveals pathogenic mutations in familial cases in steroid-sensitive nephrotic syndrome (SSNS and sheds light on possible mechanisms and key molecules in podocytes in MCD. On the other hand, in the majority of cases, the existence of circulating permeability factors has been implicated along with T lymphocyte dysfunction. Observations of benefit with rituximab added B cell involvement to the disease. Animal models are unsatisfactory, and the humanized mouse may be a good model that well reflects MCD pathophysiology to investigate suggested “T cell dysfunction” directly related to podocytes in vivo. Several candidate circulating factors and their effects on podocytes have been proposed but are still not sufficient to explain whole mechanisms and clinical features in MCD. Another circulating factor disease is focal segmental glomerulosclerosis (FSGS, and it is not clear if this is a distinct entity, or on the same spectrum, implicating the same circulating factor(s. These patients are mostly steroid resistant and often have a rapid relapse after transplantation. In clinical practice, predicting relapse or disease activity and response to steroids is important and is an area where novel biomarkers can be developed based on our growing knowledge of podocyte signaling pathways. In this review, we discuss recent findings in genetics and

  19. Blueprint for a minimal photoautotrophic cell: conserved and variable genes in Synechococcus elongatus PCC 7942

    Directory of Open Access Journals (Sweden)

    Peretó Juli

    2011-01-01

    Full Text Available Abstract Background Simpler biological systems should be easier to understand and to engineer towards pre-defined goals. One way to achieve biological simplicity is through genome minimization. Here we looked for genomic islands in the fresh water cyanobacteria Synechococcus elongatus PCC 7942 (genome size 2.7 Mb that could be used as targets for deletion. We also looked for conserved genes that might be essential for cell survival. Results By using a combination of methods we identified 170 xenologs, 136 ORFans and 1401 core genes in the genome of S. elongatus PCC 7942. These represent 6.5%, 5.2% and 53.6% of the annotated genes respectively. We considered that genes in genomic islands could be found if they showed a combination of: a unusual G+C content; b unusual phylogenetic similarity; and/or c a small number of the highly iterated palindrome 1 (HIP1 motif plus an unusual codon usage. The origin of the largest genomic island by horizontal gene transfer (HGT could be corroborated by lack of coverage among metagenomic sequences from a fresh water microbialite. Evidence is also presented that xenologous genes tend to cluster in operons. Interestingly, most genes coding for proteins with a diguanylate cyclase domain are predicted to be xenologs, suggesting a role for horizontal gene transfer in the evolution of Synechococcus sensory systems. Conclusions Our estimates of genomic islands in PCC 7942 are larger than those predicted by other published methods like SIGI-HMM. Our results set a guide to non-essential genes in S. elongatus PCC 7942 indicating a path towards the engineering of a model photoautotrophic bacterial cell.

  20. Advanced Passivation Technology and Loss Factor Minimization for High Efficiency Solar Cells.

    Science.gov (United States)

    Park, Cheolmin; Balaji, Nagarajan; Jung, Sungwook; Choi, Jaewoo; Ju, Minkyu; Lee, Seunghwan; Kim, Jungmo; Bong, Sungjae; Chung, Sungyoun; Lee, Youn-Jung; Yi, Junsin

    2015-10-01

    High-efficiency Si solar cells have attracted great attention from researchers, scientists, photovoltaic (PV) industry engineers for the past few decades. With thin wafers, surface passivation becomes necessary to increase the solar cells efficiency by overcoming several induced effects due to associated crystal defects and impurities of c-Si. This paper discusses suitable passivation schemes and optimization techniques to achieve high efficiency at low cost. SiNx film was optimized with higher transmittance and reduced recombination for using as an effective antireflection and passivation layer to attain higher solar cell efficiencies. The higher band gap increased the transmittance with reduced defect states that persisted at 1.68 and 1.80 eV in SiNx films. The thermal stability of SiN (Si-rich)/SiN (N-rich) stacks was also studied. Si-rich SiN with a refractive index of 2.7 was used as a passivation layer and N-rich SiN with a refractive index of 2.1 was used for thermal stability. An implied Voc of 720 mV with a stable lifetime of 1.5 ms was obtained for the stack layer after firing. Si-N and Si-H bonding concentration was analyzed by FTIR for the correlation of thermally stable passivation mechanism. The passivation property of spin coated Al2O3 films was also investigated. An effective surface recombination velocity of 55 cm/s with a high density of negative fixed charges (Qf) on the order of 9 x 10(11) cm(-2) was detected in Al2O3 films. PMID:26726397

  1. Minimal Surfaces for Stereo

    OpenAIRE

    Cohen, Michael F.; Buehler, Chris; Gortler, Steven; Mcmillan, Leonard

    2002-01-01

    Determining shape from stereo has often been posed as a global minimization problem. Once formulated, the minimization problems are then solved with a variety of algorithmic approaches. These approaches include techniques such as dynamic programming min-cut and alpha-expansion. In this paper we show how an algorithmic technique that constructs a discrete spatial minimal cost surface can be brought to bear on stereo global minimization problems. This problem can then be reduced to a single min...

  2. Diffusion-weighted magnetic resonance imaging in the differentiation of angiomyolipoma with minimal fat from clear cell renal cell carcinoma

    International Nuclear Information System (INIS)

    The aim of the present study was to evaluate diffusion-weighted (DW) magnetic resonance imaging (MRI) in differentiating between minimal fat angiomyolipoma (MFAML) and clear cell renal cell carcinoma (CCRCC). Forty-one solid renal tumors without visible macroscopic fat on unenhanced computed tomography images were evaluated by MRI, including DW-MRI, and were diagnosed pathologically as CCRCC (n=36) or MFAML (n=5). To evaluate the heterogeneity of diffusion in each tumor, the signals of the tumors on DW-MRI were analyzed subjectively and the apparent diffusion coefficient (ADC) values and histograms assessed objectively. Thirty-three of 36 CCRCC (92%) exhibited a heterogeneous signal on DW-MRI and several peaks in the ADC value histogram, whereas four of five MFAML exhibited a homogeneous signal on DW-MRI and a single prominent peak in the histogram. The standard deviations of the ADC values were significantly smaller for MFAML than for CCRCC (P=0.0015). In conclusion, DW-MRI can be considered a useful and noninvasive addition to the preoperative differentiation of CCRCC and MFAML. (author)

  3. A hospital-based cost minimization study of the potential financial impact on the UK health care system of introduction of iron isomaltoside 1000

    Directory of Open Access Journals (Sweden)

    Sunil Bhandari

    2011-03-01

    deficiency anemia, high dose, single dose, parenteral iron, cost minimization

  4. High-efficiency cell concepts on low-cost silicon sheets

    Science.gov (United States)

    Bell, R. O.; Ravi, K. V.

    1985-01-01

    The limitations on sheet growth material in terms of the defect structure and minority carrier lifetime are discussed. The effect of various defects on performance are estimated. Given these limitations designs for a sheet growth cell that will make the best of the material characteristics are proposed. Achievement of optimum synergy between base material quality and device processing variables is proposed. A strong coupling exists between material quality and the variables during crystal growth, and device processing variables. Two objectives are outlined: (1) optimization of the coupling for maximum performance at minimal cost; and (2) decoupling of materials from processing by improvement in base material quality to make it less sensitive to processing variables.

  5. Durable, Low-cost, Improved Fuel Cell Membranes

    Energy Technology Data Exchange (ETDEWEB)

    Chris Roger; David Mountz; Wensheng He; Tao Zhang

    2011-03-17

    The development of low cost, durable membranes and membranes electrode assemblies (MEAs) that operate under reduced relative humidity (RH) conditions remain a critical challenge for the successful introduction of fuel cells into mass markets. It was the goal of the team lead by Arkema, Inc. to address these shortages. Thus, this project addresses the following technical barriers from the fuel cells section of the Hydrogen Fuel Cells and Infrastructure Technologies Program Multi-Year Research, Development and Demonstration Plan: (A) Durability (B) Cost Arkema’s approach consisted of using blends of polyvinylidenefluoride (PVDF) and proprietary sulfonated polyelectrolytes. In the traditional approach to polyelectrolytes for proton exchange membranes (PEM), all the required properties are “packaged” in one macromolecule. The properties of interest include proton conductivity, mechanical properties, durability, and water/gas transport. This is the case, for example, for perfluorosulfonic acid-containing (PFSA) membranes. However, the cost of these materials is high, largely due to the complexity and the number of steps involved in their synthesis. In addition, they suffer other shortcomings such as mediocre mechanical properties and insufficient durability for some applications. The strength and originality of Arkema’s approach lies in the decoupling of ion conductivity from the other requirements. Kynar® PVDF provides an exceptional combination of properties that make it ideally suited for a membrane matrix (Kynar® is a registered trademark of Arkema Inc.). It exhibits outstanding chemical resistance in highly oxidative and acidic environments. In work with a prior grant, a membrane known as M41 was developed by Arkema. M41 had many of the properties needed for a high performance PEM, but had a significant deficiency in conductivity at low RH. In the first phase of this work, the processing parameters of M41 were explored as a means to increase its proton

  6. Life-cycle cost comparisons of advanced storage batteries and fuel cells for utility, stand-alone, and electric vehicle applications

    Energy Technology Data Exchange (ETDEWEB)

    Humphreys, K.K.; Brown, D.R.

    1990-01-01

    This report presents a comparison of battery and fuel cell economics for ten different technologies. To develop an equitable economic comparison, the technologies were evaluated on a life-cycle cost (LCC) basis. The LCC comparison involved normalizing source estimates to a standard set of assumptions and preparing a lifetime cost scenario for each technology, including the initial capital cost, replacement costs, operating and maintenance (O M) costs, auxiliary energy costs, costs due to system inefficiencies, the cost of energy stored, and salvage costs or credits. By considering all the costs associated with each technology over its respective lifetime, the technology that is most economical to operate over any given period of time can be determined. An analysis of this type indicates whether paying a high initial capital cost for a technology with low O M costs is more or less economical on a lifetime basis than purchasing a technology with a low initial capital cost and high O M costs. It is important to realize that while minimizing cost is important, the customer will not always purchase the least expensive technology. The customer may identify benefits associated with a more expensive option that make it the more attractive over all (e.g., reduced construction lead times, modularity, environmental benefits, spinning reserve, etc.). The LCC estimates presented in this report represent three end-use applications: utility load-leveling, stand-alone power systems, and electric vehicles.

  7. Synthesis of CZTS Nanoparticles for Low-Cost Solar Cells.

    Science.gov (United States)

    Kim, Donguk; Kim, Minha; Shim, Joongpyo; Kim, Doyoung; Choi, Wonseok; Park, Yong Seob; Choi, Youngkwan; Lee, Jaehyeong

    2016-05-01

    In this work, uniformly sized Cu2ZnSnS4 (CZTS) nanoparticles with easy control of chemical composition were synthesized and printable ink containing CZTS nanoparticles was prepared for low-cost-solar cell applications. In addition, we studied the effects of synthesis conditions, such as reaction temperature and time, on properties of the CZTS nanoparticles. For CZTS nanoparticles synthesis process, the reactants were mixed as the 2:1:1:4 molar ratios. The reaction temperature and time was varied from 220 degrees C to 320 degrees C and from 3 hours to 5 hours, respectively. The crystal structure and morphology of CZTS nanoparticles prepared under the various conditions were investigated by X-ray diffraction (XRD) and field-emission scanning electron microscopy (FE-SEM), and energy dispersive X-ray spectroscopy (EDS) was used for compositional analysis of the CZTS nanoparticles. PMID:27483876

  8. Minimal resolution

    OpenAIRE

    Weidenbach, C.

    1994-01-01

    Minimal resolution restricts the applicability of resolution and factorization to minimal literals. Minimality is an abstract criterion. It is shown that if the minimality criterion satisfies certain properties minimal resolution is sound and complete. Hyper resolution, ordered resolution and lock resolution are known instances of minimal resolution. We also introduce new instances of the general completeness result, correct some mistakes in existing literature and give some general redundanc...

  9. Validation of a Low-Cost Paper-Based Screening Test for Sickle Cell Anemia.

    Directory of Open Access Journals (Sweden)

    Nathaniel Z Piety

    Full Text Available The high childhood mortality and life-long complications associated with sickle cell anemia (SCA in developing countries could be significantly reduced with effective prophylaxis and education if SCA is diagnosed early in life. However, conventional laboratory methods used for diagnosing SCA remain prohibitively expensive and impractical in this setting. This study describes the clinical validation of a low-cost paper-based test for SCA that can accurately identify sickle trait carriers (HbAS and individuals with SCA (HbSS among adults and children over 1 year of age.In a population of healthy volunteers and SCA patients in the United States (n = 55 the test identified individuals whose blood contained any HbS (HbAS and HbSS with 100% sensitivity and 100% specificity for both visual evaluation and automated analysis, and detected SCA (HbSS with 93% sensitivity and 94% specificity for visual evaluation and 100% sensitivity and 97% specificity for automated analysis. In a population of post-partum women (with a previously unknown SCA status at a primary obstetric hospital in Cabinda, Angola (n = 226 the test identified sickle cell trait carriers with 94% sensitivity and 97% specificity using visual evaluation (none of the women had SCA. Notably, our test permits instrument- and electricity-free visual diagnostics, requires minimal training to be performed, can be completed within 30 minutes, and costs about $0.07 in test-specific consumable materials.Our results validate the paper-based SCA test as a useful low-cost tool for screening adults and children for sickle trait and disease and demonstrate its practicality in resource-limited clinical settings.

  10. Comparative costs of flexible package cells and rigid cells for lithium-ionhybrid electric vehicle batteries.

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, P. A.; Jansen, A. N.

    2006-11-28

    We conducted a design study to compare the manufacturing costs at a level of 100,000 hybrid vehicle batteries per year for flexible package (Flex) cells and for rigid aluminum container (Rigid) cells. Initially, the Rigid cells were considered to have welded closures and to be deep-drawn containers of about the same shape as the Flex cells. As the study progressed, the method of fabricating and sealing the Rigid cells was expanded to include lower cost options including double seaming and other mechanically fastened closures with polymer sealants. Both types of batteries were designed with positive electrodes containing Li(Ni{sub 1/3}Co{sub 1/3}Mn{sub 1/3})O{sub 2} and graphite negative electrodes. The use of a different combination of lithium-ion electrodes would have little effect on the difference in costs for the two types of cells. We found that 20-Ah cells could be designed with excellent performance and heat rejection capabilities for either type of cell. Many parts in the design of the Flex cells are identical or nearly identical to those of the Rigid Cell, so for these features there would be no difference in the cost of manufacturing the two types of batteries. We judged the performance, size and weight of the batteries to be sufficiently similar that the batteries would have the same value for their application. Some of the design features of the Flex cells were markedly different than those of the deep-drawn and welded Rigid cells and would result in significant cost savings. Fabrication and processing steps for which the Flex cells appear to have a cost advantage over these Rigid cells are (1) container fabrication and sealing, (2) terminal fabrication and sealing, and (3) intercell connections. The costs of providing cooling channels adjacent to the cells and for module and battery hardware appear to favor Rigid cell batteries slightly. Overall, Flex cell batteries appear to have an advantage of about $1.20-$3.70 per cell for a 25-kW Battery of 20

  11. Efficient Cells Cut the Cost of Solar Power

    Science.gov (United States)

    2013-01-01

    If you visit Glenn Research Center, you might encounter a photovoltaic (PV) array that looks unlike anything you've ever seen. In fact, what one would normally identify as the panel is actually a series of curved mirrors called solar concentrators, engineered to reflect sunlight rather than absorb it. These concentrators gather, intensify, and focus sun beams upward, aiming at a fixture containing specialized silicon concentrated PV chips the actual solar cells. If you stay by the array for a while, you'll notice that the solar concentrators follow the path of the sun throughout the day, changing position to best capture and utilize the sunlight. The specialized chips that make the technology possible are the brainchild of Bernard Sater, an engineer who had worked at Glenn since the early 1960s before retiring to pursue his unique ideas for harnessing solar power. Sater contributed to multiple PV projects in the latter part of his career at the Center, including research and development on the International Space Station s solar arrays. In his spare time, he enjoyed tinkering with new approaches to solar power, experiments that resulted in the system installed at Glenn today. Sater s basic idea had two components. First, he wanted to create a silicon cell that was smaller, more efficient, and much lower cost than those available at the time. To ensure that the potential of such a chip could be realized, he also planned on pairing it with a system that could concentrate sunlight and focus it directly on the cell. When he retired from Glenn in 1994 to focus on researching and developing the technology full time, Sater found that NASA was interested in the concept and ready to provide funding, facilities, and expertise in order to assist in its development.

  12. Low cost and efficient photovoltaic conversion by nanocrystalline solar cells

    International Nuclear Information System (INIS)

    The quality of human life depends to a large degree on the availability of energy sources. The present worldwide energy consumption already exceeds the level of 6000 gigawatt and is expected to further increase sharply. This implies enhanced depletion of fossil fuel reserves, leading to further aggravation of the environmental pollution. Adding to this the dangers arising from the accumulation of plutonium fission products from nuclear reactors, the quality of life on earth is threatened unless renewable energy resources can be quickly developed. Photovoltaic solar energy converters are expected to make important contributions to the identification of environmentally friendly solutions to the energy problem. One attractive strategy discussed in this paper is the development of systems that mimic natural photosynthesis in the conversion of solar energy for the fixation of carbon dioxide. A molecular photovoltaic device has been developed whose overall efficiency for solar energy conversion to electricity has already attained 10%. The system is based on the sensitization of nanocrystalline films by transition metal charge transfer sensitizers. In analogy to photosynthesis, the new chemical solar cell achieves the separation of the light absorption and charge carrier transport processes. Extraordinary yields exceeding 90% for the conversion of incident photons into electric current are obtained, in contrast to conventional photovoltaic cells which are not economical for base load utility electricity production. The low cost and ease of production of the new cell should benefit large-scale applications, in particular in underdeveloped or developing countries, which benefit from generous sunshine. Aside from its intrinsic merits as a photovoltaic device, nanocrystalline film development opens up a large number of additional avenues for energy storage ranging from intercalation batteries to the formation of chemical fuels. These systems will undoubtedly promote the

  13. Clinical presentation of minimally invasive and in situ squamous cell carcinoma of the anus in homosexual men.

    Science.gov (United States)

    Forti, R L; Medwell, S J; Aboulafia, D M; Surawicz, C M; Spach, D H

    1995-09-01

    From January 1988 to December 1993, we identified six men with minimally invasive (stage I) squamous cell carcinoma of the anus and 10 men with anal carcinoma in situ (CIS). Of the six patients with invasive carcinoma, four were infected with human immunodeficiency virus (HIV), including one with AIDS. Of the 10 patients with CIS, eight were infected with HIV, including four with AIDS. Anal pain and bleeding were the most common symptoms of minimally invasive anal cancer and anal CIS. Anal irritation, burning, or pruritus occurred more frequently in patients with CIS, whereas anal ulcers, masses, or abscesses were more frequent in patients with minimally invasive cancer. Several patients with CIS had a discrete area of leukoplakia in the anal canal or a pigmented plaque of the anus and anal canal. These lesions were not observed in patients with minimally invasive anal cancer. The symptoms and signs of early-stage anal cancer in men at risk for developing HIV infection or men infected with HIV often resemble those of other common anorectal diseases in homosexual men. Anal cancer in HIV-infected men is not limited to those individuals with AIDS. PMID:8527551

  14. Pancratistatin induces apoptosis in clinical leukemia samples with minimal effect on non-cancerous peripheral blood mononuclear cells

    Directory of Open Access Journals (Sweden)

    McNulty James

    2010-03-01

    Full Text Available Abstract Background Pancratistatin, a natural compound extracted from Hymenocallis littoralis, can selectively induce apoptosis in several cancer cell lines. In this ex vivo study, we evaluated the effect of pancratistatin on peripheral blood mononuclear cells obtained from 15 leukemia patients prior to clinical intervention of newly diagnosed patients, as well as others of different ages in relapse and at various disease progression states. Results Mononuclear cells from healthy volunteers and leukemia patients were exposed to 1 μM pancratistatin for up to 48 h. Irrespective of leukemia type, pancratistatin induced apoptosis in the leukemic samples, with minimal effects on non-cancerous peripheral blood mononuclear control cells. Conclusion Our results show that pancratistatin is an effective and selective anti-cancer agent with potential for advancement to clinical trials.

  15. 基于病人成本最小化的医院预约挂号研究%Hospital Appointment and Registration Management Based on Minimization Patients Cost

    Institute of Scientific and Technical Information of China (English)

    郑忠伟; 范丽繁; 王婧

    2009-01-01

    为了减少病人排队挂号的等待时间及优化医院自身资源的合理配置,近几年我国各大医院都先后开展预约挂号服务.然而,医院在开展预约挂号时面临的问题是:预约挂号为病人带来了多少好处和便捷,预约数量和病人总挂号成本存在什么样的关系,到底开放多少预约号最为合适?本文从病人的角度对上述问题进行了定量研究.论文将病人的挂号成本分为时间成本和费用成本两类,运用了排队论建立了预约量与病人总挂号成本的模型,得出了预约挂号的个体选择依据和系统选择依据,并从总挂号成本与预约量的关系中得到使所有病人总挂号成本最小的最优预约量.然后,进一步分析了最优预约量中各个参数的敏感性,以期为医院的预约挂号管理工作提供指导.%In order to decrease patient's waiting time and optimize the collocation of hospital's resource, many large hospitals have recently developed the appointment and registration system. However, there are some issues when hospitals are developing the system--how much benefit and convenience the system brings to patients,what relationship is between the appointment amount and the total registration cost, and how many appointment is optimal. All these problems are considered in this paper by quantitative analysis from patients' point. The patients' total registration cost is divided into time cost and fee cost. Using the results of the queuing theory, we build the model about the appointment amount and the total registration cost,and gain the individual selection principle and system selection principle of the appointment and registration , respectively. And we have a conclusion that there exists an optimal appointment amount which minimizes the total registration cost.Then,when all parameters are given,we can compute out the optimal appointment amount. Finally,the sensitivity of all parameters is analyzed, in order to provide

  16. Evaluation of the Total Cost of Ownership of Fuel Cell-Powered Material Handling Equipment

    Energy Technology Data Exchange (ETDEWEB)

    Ramsden, T.

    2013-04-01

    This report discusses an analysis of the total cost of ownership of fuel cell-powered and traditional battery-powered material handling equipment (MHE, or more typically 'forklifts'). A number of fuel cell MHE deployments have received funding support from the federal government. Using data from these government co-funded deployments, DOE's National Renewable Energy Laboratory (NREL) has been evaluating the performance of fuel cells in material handling applications. NREL has assessed the total cost of ownership of fuel cell MHE and compared it to the cost of ownership of traditional battery-powered MHE. As part of its cost of ownership assessment, NREL looked at a range of costs associated with MHE operation, including the capital costs of battery and fuel cell systems, the cost of supporting infrastructure, maintenance costs, warehouse space costs, and labor costs. Considering all these costs, NREL found that fuel cell MHE can have a lower overall cost of ownership than comparable battery-powered MHE.

  17. Bacillus subtilis and Escherichia coli essential genes and minimal cell factories after one decade of genome engineering.

    Science.gov (United States)

    Juhas, Mario; Reuß, Daniel R; Zhu, Bingyao; Commichau, Fabian M

    2014-11-01

    Investigation of essential genes, besides contributing to understanding the fundamental principles of life, has numerous practical applications. Essential genes can be exploited as building blocks of a tightly controlled cell 'chassis'. Bacillus subtilis and Escherichia coli K-12 are both well-characterized model bacteria used as hosts for a plethora of biotechnological applications. Determination of the essential genes that constitute the B. subtilis and E. coli minimal genomes is therefore of the highest importance. Recent advances have led to the modification of the original B. subtilis and E. coli essential gene sets identified 10 years ago. Furthermore, significant progress has been made in the area of genome minimization of both model bacteria. This review provides an update, with particular emphasis on the current essential gene sets and their comparison with the original gene sets identified 10 years ago. Special attention is focused on the genome reduction analyses in B. subtilis and E. coli and the construction of minimal cell factories for industrial applications. PMID:25092907

  18. Cryoprotective Effect of Disaccharides on Cord Blood Stem Cells with Minimal Use of DMSO

    OpenAIRE

    Mantri, Santwana; Kanungo, Shyama; Mohapatra, P. C.

    2014-01-01

    Umbilical cord blood (UCB) is an extremely attractive source of stem cells for the treatment of various benign and malignant hematological and non-hematological disorders. To facilitate the preservation of these stem cells, 10 % dimethylsulfoxide (DMSO) is widely used as cryoprotectant in cord blood banks. But it is found to be toxic at this concentration with the result of serious side effects in recipients after infusion of DMSO-cryopreserved cells. Evaluation of viability and functionality...

  19. Single cells spreading on a protein lattice adopt an energy minimizing shape.

    OpenAIRE

    Vianay, Benoit; Käfer, Jos; Planus, Emmanuelle; Block, Marc,; Graner, François; Guillou, Hervé

    2010-01-01

    When spreading onto a protein microlattice living cells spontaneously acquire simple shapes determined by the lattice geometry. This suggests that, on a lattice, living cells' shapes are in thermodynamic metastable states. Using a model at thermodynamic equilibrium we are able to reproduce the observed shapes. We build a phase diagram based on two adimensional parameters characterizing essential cellular properties involved in spreading: the cell's compressibility and fluctuations.

  20. Quantum processes in 8-Oxo-Guanine-Ru(bipyridine){3/2+} photosynthetic systems of artificial minimal cells

    Science.gov (United States)

    Tamulis, Arvydas; Grigalavicius, Mantas; Krisciukaitis, Sarunas; Medzevicius, Giedrius

    2011-06-01

    Density functional theory methods were used to investigate various self-assembled photoactive bioorganic systems of interest for artificial minimal cells. The cell systems studied are based on nucleotides or their compounds and consisted of up to 123 atoms (not including the associated water or methanol solvent shells) and are up to 2.5 nm in diameter. The electron correlation interactions responsible for the weak hydrogen and Van derWaals chemical bonds increase due to the addition of a polar solvent (water or methanol). The precursor fatty acid molecules of the system also play a critical role in the quantum mechanical interaction based self-assembly of the photosynthetic center and the functioning of the photosynthetic processes of the artificial minimal cells. The distances between the separated sensitizer, fatty acid precursor, and methanol molecules are comparable to Van derWaals and hydrogen bonding radii. As a result the associated electron correlation interactions compress the overall system, resulting in an even smaller gap between the highest occupied molecular orbital (HOMO), and lowest unoccupied molecular orbital (LUMO) electron energy levels and photoexcited electron tunnelling occurs from the sensitizer (either Ru(bpy){3/2+} or [Ru(bpy)2(4-Bu-4'-Me-2,2'-bpy)]2++ derivatives) to the precursor fatty acid molecules (notation used: Me = methyl; Bu = butyl; bpy = bipyridine). The shift of the absorption spectrum to the red for the artificial protocell photosynthetic centers might be considered as the measure of the complexity of these systems.

  1. Minimal surfaces

    CERN Document Server

    Dierkes, Ulrich; Sauvigny, Friedrich; Jakob, Ruben; Kuster, Albrecht

    2010-01-01

    Minimal Surfaces is the first volume of a three volume treatise on minimal surfaces (Grundlehren Nr. 339-341). Each volume can be read and studied independently of the others. The central theme is boundary value problems for minimal surfaces. The treatise is a substantially revised and extended version of the monograph Minimal Surfaces I, II (Grundlehren Nr. 295 & 296). The first volume begins with an exposition of basic ideas of the theory of surfaces in three-dimensional Euclidean space, followed by an introduction of minimal surfaces as stationary points of area, or equivalently

  2. A standardized procedure to obtain mesenchymal stem/stromal cells from minimally manipulated dental pulp and Wharton's jelly samples.

    Science.gov (United States)

    Ducret, M; Fabre, H; Degoult, O; Atzeni, G; McGuckin, C; Forraz, N; Mallein-Gerrin, F; Perrier-Groult, E; Fargues, J C

    2016-01-01

    Transplantation of mesenchymal stem/stromalcells (MSCs) has emerged as an effectivemethod to treat diseased or damagedorgans and tissues, and hundreds of clinicaltrials using MSCs are currently under way todemonstrate the validity of such a therapeuticapproach. However, most MSCs used for clinicaltrials are prepared in research laboratorieswith insufficient manufacturing quality control.In particular, laboratories lack standardizedprocedures for in vitro isolation of MSCs fromtissue samples, resulting in heterogeneouspopulations of cells and variable experimentaland clinical results.MSCs are now referred to as Human CellularTissue-based Products or Advanced TherapyMedicinal Products, and guidelines fromthe American Code of Federal Regulation ofthe Food and Drug Administration (21 CFRPart 1271) and from the European MedicinesAgency (European Directive 1394/2007) definerequirements for appropriate production ofthese cells. These guidelines, commonly called"Good Manufacturing Practices" (GMP),include recommendations about laboratorycell culture procedures to ensure optimal reproducibility,efficacy and safety of the finalmedicinal product. In particular, the Food andDrug Administration divides ex vivo culturedcells into "minimally" and "more than minimally"manipulated samples, in function of theuse or not of procedures "that might alter thebiological features of the cells". Today, minimalmanipulation conditions have not beendefined for the collection and isolation ofMSCs (Torre et al. 2015)(Ducret et al. 2015).Most if not all culture protocols that have beenreported so far are unsatisfactory, becauseof the use of xeno- or allogeneic cell culturemedia, enzymatic treatment and long-termcell amplification that are known to alter thequality of MSCs.The aim of this study was to describe a standardizedprocedure for recovering MSCs withminimal handling from two promising sources,the dental pulp (DP) and the Wharton's jelly(WJ) of the umbilical cord. The quality and

  3. Environmental protection by cost minimization: Least Cost Planning for traffic. Includes a guide for the application in local communities; Umweltentlastung durch Kostenminimierung: Least Cost Planning im Verkehr. Mit Leitfaden fuer die Anwendung in Kommunen

    Energy Technology Data Exchange (ETDEWEB)

    Bracher, T.; Diegmann, V.; Eckart, C.F.; Liwicki, M.; Lobenberg, G.; Wetzel, C. [Gesellschaft fuer Informatik, Verkehrs- und Umweltplanung mbH (IVU), Berlin (Germany); Bergmann, M.; Uricher, A.; Lueers, A. [Oeko-Institut, Inst. fuer Angewandte Oekologie e.V., Freiburg im Breisgau (Germany); Becker, U.; Karl, G.; Karl, B.; Voellings, A. [Technische Univ. Dresden (Germany). Lehrstuhl fuer Verkehrsoekologie

    1999-08-01

    An intermodal approach for the evaluation of transportation services on the municipal level was developed. Both non-motorised and motorised transportation were included. The approach aims at helping communities to provide an economically and ecologically viable transport policy. Least Cost Transportation Planning (LCTP) was developed to transfer the successful concept of Least Cost Planning from the energy sector to transportation. The conclusion from an analysis of LCTP literature and present evaluation methods was that an improved approach should be intermodal and integrate users, public bodies and transport companies as well as all planning sectors. An approach was developed firstly to identify and clarify transportation expenditures and incomes of a city within a year, and secondly for the evaluation of planning alternatives. This was illustrated for the access system of an industrial area with adjacent railway services in the town of Freiburg. Three alternatives were compared: the extension of a tramway line, the upgrading of the present bus system, and the development of a service and bicycle provision concept for rail stations and companies. Besides income and expenditure for each alternative, the effects on transport demand, the impact on air pollution and noise and on space consumption were presented. As a result, the bicycle concept is in most items better than its alternatives. The final report has three volumes and there is an extra guideline for implementing the method within municipalities. It includes a set of excel sheet tables for an easy application (all in German). (orig.) [German] Fuer die Verkehrsplanung wurde ein verkehrstraegeruebergreifendes Bewertungsverfahren fuer Kommunen entwickelt, das motorisierte und nicht motorisierte Verkehrstraeger einbezieht. Das Verfahren soll Gemeinden unterstuetzen, eine oekonomische und oekologisch vertraegliche Verkehrspolitik zu verfolgen. Least Cost Transportation Planning (LCTP) zielt darauf ab, das fuer

  4. Minimal volume regulation after shrinkage of red blood cells from five species of reptiles

    DEFF Research Database (Denmark)

    Kristensen, Karina; Berenbrink, Michael; Koldkjær, Pia;

    2008-01-01

    Red blood cells (RBCs) from most vertebrates restore volume upon hypertonic shrinkage and the mechanisms underlying this regulatory volume increase (RVI) have been studied extensively in these cells. Despite the phylogenetically interesting position of reptiles, very little is known about their red...... cell function. The present study demonstrates that oxygenated RBCs in all major groups of reptiles exhibit no or a very reduced RVI upon ~ 25% calculated hyperosmotic shrinkage. Thus, RBCs from the snakes Crotalus durissus and Python regius, the turtle Trachemys scripta and the alligator Alligator...... mississippiensis showed no statistically significant RVI within 120 min after shrinkage, while the lizard Tupinambis merianae showed 22% volume recovery after 120 min. Amiloride (10- 4 M) and bumetanide (10- 5 M) had no effect on the RVI in T. merianae, indicating no involvement of the Na+/H+ exchanger (NHE) or...

  5. Radiotherapeutic Management of Non-Small Cell Lung Cancer in the Minimal Resource Setting.

    Science.gov (United States)

    Rodin, Danielle; Grover, Surbhi; Xu, Melody J; Hanna, Timothy P; Olson, Robert; Schreiner, L John; Munshi, Anusheel; Mornex, Francoise; Palma, David; Gaspar, Laurie E

    2016-01-01

    Lung cancer is the most common cancer worldwide and the fifth most common cause of death globally. Its incidence continues to increase, especially within low- and middle-income countries (LMICs), which have limited capacity to address the growing need for treatment. The standard of care for lung cancer treatment often involves radiation therapy (RT), which plays an important therapeutic role in curative-intent treatment of early-stage to locally advanced disease, as well as in palliation. The infrastructure, equipment, and human resources required for RT may be limited in LMICs. However, this narrative review discusses the scope of the problem of lung cancer in LMICs, the role of RT technologies in lung cancer treatment, and RT capacity in developing countries. Strategies are presented for maximizing the availability and impact of RT in settings with minimal resource availability, and areas for potential future innovation are identified. Priorities for LMICs involve increasing access to RT equipment and trained health care professionals, ensuring quality of care, providing guidance on priority setting with limited resources, and encouraging innovation to increase the economic efficiency of RT delivery. Several international initiatives are currently under way and represent important first steps toward scaling up RT in LMICs to treat lung cancer. PMID:26762736

  6. Screening ethnically diverse human embryonic stem cells identifies a chromosome 20 minimal amplicon conferring growth advantage

    Czech Academy of Sciences Publication Activity Database

    Amps, K.; Andrews, P.W.; Anyfantis, G.; Armstrong, L.; Avery, S.; Baharvand, H.; Baker, J.; Baker, D.; Munoz, M. N.; Beil, S.; Benvenisty, N.; Ben-Yosef, D.; Biancotti, J. C.; Bosman, A.; Brena, R. M.; Brison, D.; Caisander, G.; Camarasa, M. V.; Chen, J. M.; Chiao, E.; Choi, Y. M.; Choo, E.; Collins, D.; Colman, A.; Crook, J. M.; Daley, G. Q.; Dalton, A.; De Sousa, P. A.; Denning, C.; Downie, J.; Dvořák, P.; Hampl, Aleš

    2011-01-01

    Roč. 29, č. 12 (2011), s. 1132-1144. ISSN 1087-0156 Institutional research plan: CEZ:AV0Z50390703 Keywords : comparative genomic hybridization * copy number variation * human es cells Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 23.268, year: 2011

  7. RF Cell Modeling and Experiments for Wakefield Minimization in DARHT-II

    CERN Document Server

    Nelson, S D; Nelson, Scott D.; Vella, Michael

    2000-01-01

    Electron beams of linear induction accelerators experience deflective forces caused by RF fields building up as a result of accelerating cavities of finite size. These forces can significantly effect the beam when a long linac composed of identical cells is assembled. Recent techniques in computational modeling, simulation, and experiments for 20 MeV DARHT-II (Dual Axis Radiographic Hydrodynamic Test) accelerator cells were found to reduce the wakefield impedance of the cells from 800 ohms/meter to 350 ohms/meter and experimental results confirm the results of the modeling efforts. Increased performance of the cell was obtained through a parametric study of the accelerator structure, materials, material tuning, and geometry. As a result of this effort, it was found that thickness-tuned ferrite produced a 50% deduction in the wakefield impedance in the low frequency band and was easily tunable based on the material thickness. It was also found that shaped metal sections allow for high-Q resonances to be de-tun...

  8. Fully crystalline perovskite-perylene hybrid photovoltaic cell capable of 1.2 V output with a minimized voltage loss

    Directory of Open Access Journals (Sweden)

    Ayumi Ishii

    2014-09-01

    Full Text Available A fully crystalline heterojunction of organo-metal-halide perovskite, CH3NH3PbI3−xClx (X < 0.24, and perylene constitutes a planar photovoltaic cell that yields a photovoltage exceeding 1.2 V with a single junction cell absorbing up to 800 nm. Here, perylene not only works as a hole conductor but also contributes to photovoltage as a photoconductor. The crystalline plane orientation of perovskite prepared on TiO2 was controlled by thermal annealing such that the lead halide (110 plane that participates in carrier conduction is highly oriented to enhance the photovoltaic performance. The crystal orientation improves the heterojunction structure with perylene. For the best cell with high crystalline orientation, a total voltage loss is significantly minimized to 0.32 V with respect to the absorption band gap of 1.55 eV. The planar crystal cells generate high open-circuit voltages of 1.15–1.22 V, which is close to a theoretical maximal voltage (1.25–1.3 V described by the Shockley-Queisser efficiency limit. The cell yielded energy conversion efficiency up to 4.96%.

  9. Intermittent hypoxia hypobaric exposure minimized oxidative stress and antioxidants in brain cells of Sprague Dawleymice

    Directory of Open Access Journals (Sweden)

    Wardaya Wardaya

    2013-05-01

    Full Text Available AbstrakLatar belakang: Hipoksia hypobaric meningkatkan produksi radikal bebas, terutama spesies oksigen reaktif (ROS. Peningkatan ROS akan menyebabkan stres oksidatif bila tidak disertai dengan peningkatan enzim antioksidan. Kondisi ini dapat dikurangi dengan hipoksia hipobarik intermiten (HHI. Tujuan penelitian ini mengidentifikasi frekuensi IHH yang dapat meminimalkan efek hipoksia hipobarik terhadap stres oksidatif dan aktivitas antioksidan spesifik pada tikus Sprague Dawley.Metode: Penelitian eksperimental pada bulan Februari-April 2010, Subjek terdiri dari satu kelompok kontrol dan empat kelompok paparan pada mencit jantan Sprague Dawley. Setiap kelompok terdiri dari 5 tikus. Kelompok kontrol tidak terpapar IHH. Kelompok terpapar (dengan selang waktu satu minggu terpapar sekali, dua kali, tiga kali, atau empat kali IHH. Semua kelompok paparan dipaparkan hipobarik setara dengan ketinggian: 35.000 ft (1 menit, 25.000 ft (5 menit, dan 18.000 ft (25 menit. Jaringan otak diperiksa untuk 8-OHdG dan SOD.Hasil:Setelah tiga paparan IHH tingkat 8-OHdG sudah kembali ke nilai kontrol (P = 0,843. Tingkat SOD meningkat secara progresif pada dua, tiga, dan empat kali paparan IHH. Bahkan setelah paparan kedua, tingkat SOD sudah sama dengan nilai kontrol, 0,231 ± 0,042 (P = 0,191.Kesimpulan: Tiga kali IHH sudah dapat meminimalkan pengaruh hipoksia hipobarik terhadap stres oksidatif dan aktivitas spesifik antioksidan pada tikus Sprague Dawley.Kata kunci: hipoksia hipobarik intermiten, stres oksidatif, antioksidanAbstractBackground: Hypoxia hypobaric increase the production of free radicals, especially reactive oxygen species (ROS. The increase in ROS would cause oxidative stress when not accompanied by an increase in antioxidant enzymes. This condition may minimize by intermittent hypobaric hypoxia (IHH. This study aimed to identify the number of IHH which may minimize the effect of hypoxia hypobaric on oxidative stress and the specific activity of

  10. Thrombocytopenia model with minimal manipulation of blood cells allowing whole blood assessment of platelet function.

    Science.gov (United States)

    Tiedemann Skipper, Mette; Rubak, Peter; Halfdan Larsen, Ole; Hvas, Anne-Mette

    2016-06-01

    In vitro models of thrombocytopenia are useful research tools. Previously published models have shortcomings altering properties of platelets and other blood components. The aim of the present study was to develop a whole blood method to induce thrombocytopenia with minimal manipulation, and to describe platelet function in induced thrombocytopenia in individuals with healthy platelets. Hirudin anticoagulated blood was obtained from 20 healthy volunteers. One part of the blood was gently centrifuged at 130g for 15 minutes. The platelet-rich plasma was replaced with phosphate-buffered saline to establish thrombocytopenia. Various levels of thrombocytopenia were achieved by combining different volumes of baseline whole blood and thrombocytopenic blood. Platelet counts were measured by flow cytometry (Navios, Beckman Coulter) and routine haematological analyser (Sysmex XE-5000). Platelet function was analysed by impedance aggregometry (Multiplate® Analyzer, Roche) and by flow cytometry (Navios, Beckman Coulter) using collagen, adenosine diphosphate, thrombin receptor activating peptide-6 and ristocetin as agonists. Median baseline platelet count was 227×10(9)/l. The in vitro model yielded median platelet counts at 51×10(9)/l (range 26-93×10(9)/l). We observed minor, yet significant, changes in platelet size and maturity from baseline to modelled thrombocytopenia. In the thrombocytopenic samples, significant and positive linear associations were found between platelet count and platelet aggregation across all agonists (all p-valuesblood-based model of thrombocytopenia was established and validated. This new model serves as a useful future tool, particularly to explore platelet function in patients with thrombocytopenia. PMID:26555800

  11. A Novel and Cost Effective Approach to the Decommissioning and Decontamination of Legacy Glove Boxes - Minimizing TRU Waste and Maximizing LLW Waste - 13634

    Energy Technology Data Exchange (ETDEWEB)

    Pancake, Daniel; Rock, Cynthia M.; Creed, Richard [Argonne National Laboratory, 9700 South Cass Avenue, Lemont, IL 60439 (United States); Donohoue, Tom; Martin, E. Ray; Mason, John A. [ANTECH Corporation 9050 Marshall Court, Westminster, CO, 80031 (United States); Norton, Christopher J.; Crosby, Daniel [Environmental Alternatives, Inc., 149 Emerald Street, Suite R, Keene, NH 03431 (United States); Nachtman, Thomas J. [InstaCote, Inc., 160 C. Lavoy Road, Erie, MI, 48133 (United States)

    2013-07-01

    determine the TRU content of the boxes by assessing the activity of Am-241 (59 keV) and Pu-241 (414 keV). Using the data generated it was possible for qualified subject matter experts (SME) to assess that the gloveboxes could be consigned for disposition as LLW and not as TRU. Once this determination was assessed and accepted the gloveboxes were prepared for final disposition to the Nevada National Security Site (NNSS) - formerly the Nevada Test Site (NTS). This preparation involved fixing any remaining radioactive contamination within the gloveboxes by filling them with a foam compound, prior to transportation. Once the remaining contamination was fixed the gloveboxes were removed from the laboratory and prepared for transported by road to NNSS. This successful glovebox decontamination and decommissioning process illustrates the means by which TRU waste generation has been minimized, LLW generation has been maximized, and risk has been effectively managed. The process minimizes the volume of TRU waste and reduced the decommissioning time with significant cost savings as the result. (authors)

  12. A Novel and Cost Effective Approach to the Decommissioning and Decontamination of Legacy Glove Boxes - Minimizing TRU Waste and Maximizing LLW Waste - 13634

    International Nuclear Information System (INIS)

    determine the TRU content of the boxes by assessing the activity of Am-241 (59 keV) and Pu-241 (414 keV). Using the data generated it was possible for qualified subject matter experts (SME) to assess that the gloveboxes could be consigned for disposition as LLW and not as TRU. Once this determination was assessed and accepted the gloveboxes were prepared for final disposition to the Nevada National Security Site (NNSS) - formerly the Nevada Test Site (NTS). This preparation involved fixing any remaining radioactive contamination within the gloveboxes by filling them with a foam compound, prior to transportation. Once the remaining contamination was fixed the gloveboxes were removed from the laboratory and prepared for transported by road to NNSS. This successful glovebox decontamination and decommissioning process illustrates the means by which TRU waste generation has been minimized, LLW generation has been maximized, and risk has been effectively managed. The process minimizes the volume of TRU waste and reduced the decommissioning time with significant cost savings as the result. (authors)

  13. Single Cells Spreading on a Protein Lattice Adopt an Energy Minimizing Shape

    Science.gov (United States)

    Vianay, Benoit; Käfer, Jos; Planus, Emmanuelle; Block, Marc; Graner, François; Guillou, Hervé

    2010-09-01

    When spreading onto a protein microlattice living cells spontaneously acquire simple shapes determined by the lattice geometry. This suggests that, on a lattice, living cells’ shapes are in thermodynamic metastable states. Using a model at thermodynamic equilibrium we are able to reproduce the observed shapes. We build a phase diagram based on two adimensional parameters characterizing essential cellular properties involved in spreading: the cell’s compressibility and fluctuations.

  14. Low-cost photovoltaics: Luminescent solar concentrators and colloidal quantum dot solar cells

    Science.gov (United States)

    Leow, Shin Woei

    /emission spectra of an organic luminescent dye (LR305), the transmission coefficient and refractive index of acrylic as parameters that describe the system. Simulations suggest that for LR305, 8-10cm of luminescent material surrounding the PV cell yields the highest increase in power gain per unit area of LSC added, thereby determining the ideal spacing between PV cells in the panel. The model also predicts that for different PV cell dimensions, there exists an optimum waveguide thickness which efficiently transports photon collected by the waveguide to the PV cell with minimal loss, and maintains an even distribution of photons across the cell surface. For the case of the 12.5 by 1cm rectangular cells used in this work, the calculated waveguide thickness is 3mm. For larger cells, every 1cm increment in PV cell width should be accompanied by a 0.75mm increase in waveguide thickness to preserve peak performance. In line with the goal of pushing for cost competitive photovoltaics, the last part of this work shifts to the study of colloidal quantum dot solar cells. A combination of low temperature, highly scalable fabrication process and reduced material usage for thin films offers us a means to produce flexible and cheap solar cells. Tagging on to existing work already performed on germanium quantum dot solar cells, additional work was carried out to further characterize the material. The effect of film thickness, nano-particle surface conditions and thermal anneal were investigated. There is evidence to suggest that the quantum dot devices contain high levels of parasitic resistances. Short circuit current densities increase by up to two times with two spin-cast layers compared to four, leading to the conjecture that charge carrier life time is low with high levels of recombination. Annealing to improve carrier mobility produces devices with current densities up to 301microA, a fourfold increase, but output voltages saw a sharp decrease from 0.12V to 0.015V. In tandem with the work

  15. Low-cost photovoltaics: Luminescent solar concentrators and colloidal quantum dot solar cells

    Science.gov (United States)

    Leow, Shin Woei

    /emission spectra of an organic luminescent dye (LR305), the transmission coefficient and refractive index of acrylic as parameters that describe the system. Simulations suggest that for LR305, 8-10cm of luminescent material surrounding the PV cell yields the highest increase in power gain per unit area of LSC added, thereby determining the ideal spacing between PV cells in the panel. The model also predicts that for different PV cell dimensions, there exists an optimum waveguide thickness which efficiently transports photon collected by the waveguide to the PV cell with minimal loss, and maintains an even distribution of photons across the cell surface. For the case of the 12.5 by 1cm rectangular cells used in this work, the calculated waveguide thickness is 3mm. For larger cells, every 1cm increment in PV cell width should be accompanied by a 0.75mm increase in waveguide thickness to preserve peak performance. In line with the goal of pushing for cost competitive photovoltaics, the last part of this work shifts to the study of colloidal quantum dot solar cells. A combination of low temperature, highly scalable fabrication process and reduced material usage for thin films offers us a means to produce flexible and cheap solar cells. Tagging on to existing work already performed on germanium quantum dot solar cells, additional work was carried out to further characterize the material. The effect of film thickness, nano-particle surface conditions and thermal anneal were investigated. There is evidence to suggest that the quantum dot devices contain high levels of parasitic resistances. Short circuit current densities increase by up to two times with two spin-cast layers compared to four, leading to the conjecture that charge carrier life time is low with high levels of recombination. Annealing to improve carrier mobility produces devices with current densities up to 301microA, a fourfold increase, but output voltages saw a sharp decrease from 0.12V to 0.015V. In tandem with the work

  16. Sliver Solar Cells: High-Efficiency, Low-Cost PV Technology

    Directory of Open Access Journals (Sweden)

    Evan Franklin

    2007-01-01

    Full Text Available Sliver cells are thin, single-crystal silicon solar cells fabricated using standard fabrication technology. Sliver modules, composed of several thousand individual Sliver cells, can be efficient, low-cost, bifacial, transparent, flexible, shadow tolerant, and lightweight. Compared with current PV technology, mature Sliver technology will need 10% of the pure silicon and fewer than 5% of the wafer starts per MW of factory output. This paper deals with two distinct challenges related to Sliver cell and Sliver module production: providing a mature and robust Sliver cell fabrication method which produces a high yield of highly efficient Sliver cells, and which is suitable for transfer to industry; and, handling, electrically interconnecting, and encapsulating billions of sliver cells at low cost. Sliver cells with efficiencies of 20% have been fabricated at ANU using a reliable, optimised processing sequence, while low-cost encapsulation methods have been demonstrated using a submodule technique.

  17. Low-cost separators for enhanced power production and field application of microbial fuel cells (MFCs)

    International Nuclear Information System (INIS)

    Highlights: • Several new separators were investigated for enhanced performance of MFC. • Polypropylen80 exhibited higher power and proton/ion diffusion compared to Nafion. • Low cost separators could be used for field application of MFC. - Abstract: New and different separators were investigated as alternatives to well-known ion exchange separators such as Nafion and Cation Exchange membrane (CMI). In polarization tests, the maximum power densities of new separators without functional groups were comparatively higher than those of Nafion and CMI. The non-woven fabric Polypropylene (PP80) exhibited maximum voltage of 0.477 V (with 1000 Ω), which was similar to that of Nafion (0.481 V), and resulted in the highest power density of 121 mW/m2 (Nafion; 118 mW/m2). Polypropylene 80 and 100 exhibited relatively smaller ohmic resistances of 11 Ω and 2 Ω, respectively, compared to others with resistances ranging from 13 to 41 Ω. Concerning oxygen diffusion, all types of size selective separators exhibited high oxygen mass transfer compared to Nafion and CMI. This high oxygen diffusion was likely the reason for the lower columbic efficiencies (CE) of PP80 (44%) and PP100 (42%) compared to Nafion (50%). PP80 exhibited a high proton mass transfer coefficient (KH = 11 × 10−5cm/s) compared to all ion exchange and size selective separators included in this study. These results suggest that low-cost separators could be used for field applications of MFCs for higher cell voltage while minimizing oxygen diffusion

  18. Pathway to low-cost metallization of silicon solar cell through understanding of the silicon metal interface and plating chemistry

    International Nuclear Information System (INIS)

    Metallization is crucial to silicon solar cell performance. It is the second most expensive process step in the fabrication of a solar cell. In order to reduce the cost of solar cell, the metallization cost has to be cut down by using less metal without compromising the efficiency. Screen-printing has been used in metallizing the commercial solar cell because of the high throughput and low cost at the expense of performance. However, because of the variability in the screen-printed gridlines, the amount of Ag metal used cannot be controlled. More so, the dependence of the contact resistance on doping necessitates the use of low sheet resistance emitters, which exacerbates losses in the blue response and hence the efficiency. To balance the contact resistance and improve blue response, several approaches have been undertaken including, use of Ag pastes incorporating nanoparticle glass frits that will not diffuse excessively into a lightly doped emitter, Ni plating on lightly doped emitter through SiNx dielectric plus NiSi formation followed by Cu and/or Ag plating, light induced plating (LIP) of Ag or Cu on fired through dielectric metal seed layers formed by aerosol or inkjet or screen-printing. All these approaches require excellent adhesion and gridline conductivity to minimize the total series resistance, which impedes the collection of electrons. This paper presents the issues and the pathway to achieving high efficiency using low cost metallization technology involving inkjet-printed Ag fine gridline having 38 μm width and 3 μm height fired through the SiNx followed by Ni and Cu plating. A comprehensive analysis of silicon/metal interface, using high precision microscopy, has shown that the investigated metallization technology is appropriate for the longevity of the device

  19. Mesenchymal stem cell isolation from human umbilical cord tissue: understanding and minimizing variability in cell yield for process optimization.

    Science.gov (United States)

    Iftimia-Mander, Andreea; Hourd, Paul; Dainty, Roger; Thomas, Robert J

    2013-10-01

    Human tissue banks are a potential source of cellular material for the nascent cell-based therapy industry; umbilical cord (UC) tissue is increasingly privately banked in such facilities as a source of mesenchymal stem cells for future therapeutic use. However, early handling of UC tissue is relatively uncontrolled due to the clinical demands of the birth environment and subsequent transport logistics. It is therefore necessary to develop extraction methods that are robust to real-world operating conditions, rather than idealized operation. Cell yield, growth, and differentiation potential of UC tissue extracted cells was analyzed from tissue processed by explant and enzymatic digestion. Variability of cell yield extracted with the digestion method was significantly greater than with the explant method. This was primarily due to location within the cord tissue (higher yield from placental end) and time delay before tissue processing (substantially reduced yield with time). In contrast, extraction of cells by explant culture was more robust to these processing variables. All cells isolated showed comparable proliferative and differentiation functionality. In conclusion, given the challenge of tightly controlled operating conditions associated with isolation and shipping of UC tissue to banking facilities, explant extraction of cells offers a more robust and lower-variability extraction method than enzymatic digestion. PMID:24835260

  20. Low cost thin film poly-silicon solar cells

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-07-01

    This report presents the results of a project to design and develop a high density plasma based thin-film poly-silicon (TFPS) deposition system based on PQL proprietary advanced plasma technology to produce semiconductor quality TFPS for fabricating a TFPS solar cell. Details are given of the TFPS deposition system, the material development programme, solar cell structure, and cell efficiencies. The reproducibility of the deposition process and prospects for commercial exploitation are discussed.

  1. Development of Low Cost Contacts to Silicon Solar Cells

    Science.gov (United States)

    Iles, P. A.; Tanner, D. P.

    1979-01-01

    Different electroless plating systems were evaluated in conjunction with copper electroplating. All tests involved simultaneous deposition of front and back contacts using a standard cell materials. Cells with good adhesion and good curve fill factors were obtained using a palladium-chromium-copper metallization system. The final copper contact system was evaluated to determine if the copper would migrate at elevated temperatures. The copper migrated at elevated temperatures causing cell output degradation.

  2. [Use of minimally invasive approaches for stage I non-small cell lung cancer: A surgeon's point of view].

    Science.gov (United States)

    Thomas, P-A

    2015-10-01

    Lobectomy with lymphadenectomy is the standard of care of patients with early stage non-small cell lung cancer, and the use of minimally invasive approaches is associated with reduced morbidity when compared with thoracotomy. Segmentectomy with lymphadenectomy seems to provide a curative effect equivalent to that of lobectomy for stage IA tumours of 2 cm or smaller, and for pure or predominant ground glass opacities. The combination of lung-sparing resections with minimally invasive approaches results in preserved pulmonary function, improved quality of life and very low morbidity. This benefit persists in so-called high-risk patients. Among patients with clinical stage IA managed with sublobar resections, more than 25% are proved to have a more advanced pathologic stage at surgery, suggesting that alternative ablative therapies would result in an incomplete resection in a similar proportion. Moreover, resection samples tumour tissue that is adequate in quantity and quality, and provides material for "research biopsies" to consolidate tissue availability for clinical trials, translational research, and in biobanks. PMID:26344441

  3. Cost related sensitivity analysis for optimal operation of a grid-parallel PEM fuel cell power plant

    Science.gov (United States)

    El-Sharkh, M. Y.; Tanrioven, M.; Rahman, A.; Alam, M. S.

    Fuel cell power plants (FCPP) as a combined source of heat, power and hydrogen (CHP&H) can be considered as a potential option to supply both thermal and electrical loads. Hydrogen produced from the FCPP can be stored for future use of the FCPP or can be sold for profit. In such a system, tariff rates for purchasing or selling electricity, the fuel cost for the FCPP/thermal load, and hydrogen selling price are the main factors that affect the operational strategy. This paper presents a hybrid evolutionary programming and Hill-Climbing based approach to evaluate the impact of change of the above mentioned cost parameters on the optimal operational strategy of the FCPP. The optimal operational strategy of the FCPP for different tariffs is achieved through the estimation of the following: hourly generated power, the amount of thermal power recovered, power trade with the local grid, and the quantity of hydrogen that can be produced. Results show the importance of optimizing system cost parameters in order to minimize overall operating cost.

  4. Low cost bipolar current collector-separator for electrochemical cells

    International Nuclear Information System (INIS)

    A bipolar current collecting, cell separating element for electrochemical cells for conducting current from the anode electrode of one cell unit to cathode electrode of the adjacent cell unit comprises: (A) a pressure mold aggregate of electrically conductive carbon/graphite particles and thermoplastic fluorocarbon polymer resin particles in a weight ratio of 2.5:1 to 16:1 whereby said molded aggregated has a bulk resistivity which is less than 4x10-3 ohm/inch, (B) said molded aggregate having a fluid imprevious main body, at least one recessed chamber on one side of said main body and a plurality of spaced, conductive projections extending from the base of said chamber for contacting and permitting current flow between the electrode of adjacent cell unit, and (C) means communicating with said recessed chambers to permit introduction and removal of fluids

  5. Cost Reduction of IMM Solar Cells by Recycling Substrates Using Wet Chemical Etching Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The goal of the program is to reduce the cost of substrate reclaim for high-efficiency solar cells fabricated by an epitaxial lift-off (ELO) process, and to...

  6. Cost Reduction of IMM Solar Cells by Recycling Substrates using Wet Chemical Etching Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This program focuses on reducing the cost of substrate reclaim for high-efficiency solar cells fabricated via an epitaxial lift-off (ELO) process, while increasing...

  7. Design of cascaded low cost solar cell with CuO substrate

    Science.gov (United States)

    Samson, Mil'shtein; Anup, Pillai; Shiv, Sharma; Garo, Yessayan

    2013-12-01

    For many years the main focus of R&D in solar cells was the development of high-efficiency solar convertors. However with solar technology beginning to be a part of national grids and stand-alone power supplies for variety of individual customers, the emphasis has changed, namely, the cost per kilowatt- hour (kW-hr) started to be an important figure of merit. Although Si does dominate the market of solar convertors, this material has total cost of kilowatt-hour much higher than what the power grid is providing presently to customers. It is well known that the cost of raw semiconductor material is a major factor in formulation of the final cost of a solar cell. That motivated us to search and design a novel solar cell using cheap materials. The new p-i-n solar cell consists of hetero-structure cascade of materials with step by step decreasing energy gap. Since the lattice constant of these three materials do differ not more than 2%, the more expensive epitaxial fabrication methods can be used as well. It should be emphasized that designed solar cell is not a cascade of three solar cells connected in series. Our market study shows that Si solar panel which costs 250-400 / m2 leads to a cost of 0.12-0.30 / kW-hr. To the contrary, CuO based solar cells with Cadmium compounds on top, would cost 100 / m2. This will allow the novel solar cell to produce electricity at a cost of 0.06-0.08 / kW-hr.

  8. Design of cascaded low cost solar cell with CuO substrate

    Energy Technology Data Exchange (ETDEWEB)

    Samson, Mil' shtein; Anup, Pillai; Shiv, Sharma; Garo, Yessayan [Advanced Electronic Technology Center, ECE Dept., University of Massachusetts, Lowell, MA-01851 (United States)

    2013-12-04

    For many years the main focus of R and D in solar cells was the development of high-efficiency solar convertors. However with solar technology beginning to be a part of national grids and stand-alone power supplies for variety of individual customers, the emphasis has changed, namely, the cost per kilowatt- hour (kW-hr) started to be an important figure of merit. Although Si does dominate the market of solar convertors, this material has total cost of kilowatt-hour much higher than what the power grid is providing presently to customers. It is well known that the cost of raw semiconductor material is a major factor in formulation of the final cost of a solar cell. That motivated us to search and design a novel solar cell using cheap materials. The new p-i-n solar cell consists of hetero-structure cascade of materials with step by step decreasing energy gap. Since the lattice constant of these three materials do differ not more than 2%, the more expensive epitaxial fabrication methods can be used as well. It should be emphasized that designed solar cell is not a cascade of three solar cells connected in series. Our market study shows that Si solar panel which costs $250–400 / m{sup 2} leads to a cost of $0.12–0.30 / kW-hr. To the contrary, CuO based solar cells with Cadmium compounds on top, would cost $100 / m{sup 2}. This will allow the novel solar cell to produce electricity at a cost of $0.06–0.08 / kW-hr.

  9. Design of cascaded low cost solar cell with CuO substrate

    International Nuclear Information System (INIS)

    For many years the main focus of R and D in solar cells was the development of high-efficiency solar convertors. However with solar technology beginning to be a part of national grids and stand-alone power supplies for variety of individual customers, the emphasis has changed, namely, the cost per kilowatt- hour (kW-hr) started to be an important figure of merit. Although Si does dominate the market of solar convertors, this material has total cost of kilowatt-hour much higher than what the power grid is providing presently to customers. It is well known that the cost of raw semiconductor material is a major factor in formulation of the final cost of a solar cell. That motivated us to search and design a novel solar cell using cheap materials. The new p-i-n solar cell consists of hetero-structure cascade of materials with step by step decreasing energy gap. Since the lattice constant of these three materials do differ not more than 2%, the more expensive epitaxial fabrication methods can be used as well. It should be emphasized that designed solar cell is not a cascade of three solar cells connected in series. Our market study shows that Si solar panel which costs $250–400 / m2 leads to a cost of $0.12–0.30 / kW-hr. To the contrary, CuO based solar cells with Cadmium compounds on top, would cost $100 / m2. This will allow the novel solar cell to produce electricity at a cost of $0.06–0.08 / kW-hr

  10. Low cost and efficient photovoltaic conversion by nanocrystalline solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Graetzel, M. [Institut de Chimie Physique, Ecole Polytechnique Federal de Lausanne (Switzerland)

    1996-09-01

    Solar cells are expected to provide environmentally friendly solutions to the world`s energy supply problem. Learning from the concepts used by green plants we have developed a molecular photovoltaic device whose overall efficiency for AM 1.5 solar light to electricity has already attained 8-11%. The system is based on the sensitization of nanocrystalline oxide films by transition metal charge transfer sensitizers. In analogy to photosynthesis, the new chemical solar cell achieves the separation of the light absorption and charge carrier transport processes. Extraordinary yields for the conversion of incident photons into electric current are obtained, exceeding 90% for transition metal complexes within the wavelength range of their absorption band. The use of molten salt electrolytes together with coordination complexes of ruthenium as sensitizers and adequate sealing technology has endowed these cells with a remarkable stability making practical applications feasible. Seven industrial cooperations are presently involved in the development to bring these cells to the market. The first cells will be applied to supply electric power for consumer electronic devices. The launching of production of several products of this type is imminent and they should be on the market within the next two years. Quite aside from their intrinsic merits as photovoltaic device, the mesoscopic oxide semiconductor films developed in our laboratory offer attractive possibilities for a number of other applications. Thus, the first example of a nanocrystalline rocking chair battery will be demonstrated and its principle briefly discussed.

  11. Impact of Minimal Residual Disease, Detected by Flow Cytometry, on Outcome of Myeloablative Hematopoietic Cell Transplantation for Acute Lymphoblastic Leukemia

    Directory of Open Access Journals (Sweden)

    Merav Bar

    2014-01-01

    Full Text Available In this retrospective study, we evaluated the impact of pre- and posttransplant minimal residual disease (MRD detected by multiparametric flow cytometry (MFC on outcome in 160 patients with ALL who underwent myeloablative allogeneic hematopoietic cell transplantation (HCT. MRD was defined as detection of abnormal B or T cells by MFC with no evidence of leukemia by morphology (<5% blasts in marrow and no evidence of extramedullary disease. Among 153 patients who had pre-HCT flow data within 50 days before transplant, MRD pre-HCT increased the risk of relapse (hazard ratio (HR = 3.64; 95% confidence interval (CI, 1.87–7.09; P=.0001 and mortality (HR = 2.39; 95% CI, 1.46–3.90, P=.0005. Three-year estimates of relapse were 17% and 38% and estimated 3-year OS was 68% and 40% for patients without and with MRD pre-HCT, respectively. 144 patients had at least one flow value post-HCT, and the risk of relapse among those with MRD was higher than that among those without MRD (HR = 7.47; 95% CI, 3.30–16.92, P<.0001. The risk of mortality was also increased (HR = 3.00; 95% CI, 1.44–6.28, P=.004. These data suggest that pre- or post-HCT MRD, as detected by MFC, is associated with an increased risk of relapse and death after myeloablative HCT for ALL.

  12. Cost-effective and Rapid Blood Analysis on a Cell-phone

    OpenAIRE

    Zhu, Hongying; Sencan, Ikbal; Wong, Justin; Dimitrov, Stoyan; Tseng, Derek; Nagashima, Keita; Ozcan, Aydogan

    2013-01-01

    We demonstrate a compact and cost-effective imaging cytometry platform installed on a cell-phone for the measurement of the density of red and white blood cells as well as hemoglobin concentration in human blood samples. Fluorescent and bright-field images of blood samples are captured using separate optical attachments to the cell-phone and are rapidly processed through a custom-developed smart application running on the phone for counting of blood cells and determining hemoglobin density. W...

  13. Small-Scale Low Cost Solid Oxide Fuel Cell Power Systems

    Energy Technology Data Exchange (ETDEWEB)

    S. D. Vora

    2008-02-01

    Progress in tasks seeking greater cell power density and lower cost through new cell designs, new cell materials and lower operating temperature is summarized. The design of the program required Proof-of-Concept unit of residential capacity scale is reviewed along with a summary of results from its successful test. Attachment 1 summarizes the status of cell development. Attachment 2 summarizes the status of generator design, and Attachment 3 of BOP design.

  14. Optimal sizing of plug-in fuel cell electric vehicles using models of vehicle performance and system cost

    International Nuclear Information System (INIS)

    Highlights: ► An analytical model for vehicle performance and power-train parameters. ► Quantitative relationships between vehicle performance and power-train parameters. ► Optimal sizing rules that help designing an optimal PEM fuel cell power-train. ► An on-road testing showing the performance of the proposed vehicle. -- Abstract: This paper presents an optimal sizing method for plug-in proton exchange membrane (PEM) fuel cell and lithium-ion battery (LIB) powered city buses. We propose a theoretical model describing the relationship between components’ parameters and vehicle performance. Analysis results show that within the working range of the electric motor, the maximal velocity and driving distance are influenced linearly by the parameters of the components, e.g. fuel cell efficiency, fuel cell output power, stored hydrogen mass, vehicle auxiliary power, battery capacity, and battery average resistance. Moreover, accelerating time is also linearly dependant on the abovementioned parameters, except of those of the battery. Next, we attempt to minimize fixed and operating costs by introducing an optimal sizing problem that uses as constraints the requirements on vehicle performance. By solving this problem, we attain several optimal sizing rules. Finally, we use these rules to design a plug-in PEM fuel cell city bus and present performance results obtained by on-road testing.

  15. Minimally invasive liver resection to obtain tumor-infiltrating lymphocytes for adoptive cell therapy in patients with metastatic melanoma

    Directory of Open Access Journals (Sweden)

    Alvarez-Downing Melissa M

    2012-06-01

    Full Text Available Abstract Background Adoptive cell therapy (ACT with tumor-infiltrating lymphocytes (TIL in patients with metastatic melanoma has been reported to have a 56% overall response rate with 20% complete responders. To increase the availability of this promising therapy in patients with advanced melanoma, a minimally invasive approach to procure tumor for TIL generation is warranted. Methods A feasibility study was performed to determine the safety and efficacy of laparoscopic liver resection to generate TIL for ACT. Retrospective review of a prospectively maintained database identified 22 patients with advanced melanoma and visceral metastasis (AJCC Stage M1c who underwent laparoscopic liver resection between 1 October 2005 and 31 July 2011. The indication for resection in all patients was to receive postoperative ACT with TIL. Results Twenty patients (91% underwent resection utilizing a closed laparoscopic technique, one required hand-assistance and another required conversion to open resection. Median intraoperative blood loss was 100 mL with most cases performed without a Pringle maneuver. Median hospital stay was 3 days. Three (14% patients experienced a complication from resection with no mortality. TIL were generated from 18 of 22 (82% patients. Twelve of 15 (80% TIL tested were found to have in vitro tumor reactivity. Eleven patients (50% received the intended ACT. Two patients were rendered no evidence of disease after surgical resection, with one undergoing delayed ACT with generated TIL after relapse. Objective tumor response was seen in 5 of 11 patients (45% who received TIL, with one patient experiencing an ongoing complete response (32+ months. Conclusions Laparoscopic liver resection can be performed with minimal morbidity and serve as an effective means to procure tumor to generate therapeutic TIL for ACT to patients with metastatic melanoma.

  16. Cost-benefit analysis for waste compaction alternatives at Lawrence Livermore National Laboratory: Addendum A to the Waste Minimization and Pollution Prevention Awareness Plan of May 31, 1991

    International Nuclear Information System (INIS)

    This report presents a cost-benefit analysis of the potential procurement and operation of various solid waste compactors or of the use of commercial compaction services, for compaction of solid transuranic (TRU), low-level radioactive, hazardous, and mixed wastes at Lawrence Livermore National Laboratory (LLNL) Hazardous Waste Management (HWM) facilities. The cost-benefit analysis was conducted to determine if increased compaction capacity at HWM might afford the potential for significant waste volume reduction and annual savings in material, shipping, labor, and disposal costs

  17. Cost Analysis of Monitoring Asthma Treatment using Sputum Cell Counts

    Directory of Open Access Journals (Sweden)

    Liesel D’silva

    2008-01-01

    Full Text Available BACKGROUND: In a four-centre trial, the use of sputum cell counts (sputum strategy [SS] to guide treatment had resulted in fewer and less severe exacerbations without the need for a higher corticosteroid dose, compared with the use of symptoms and spirometry (clinical strategy [CS].

  18. Industrial cost effective n-pasha solar cells with >20% efficiency

    Energy Technology Data Exchange (ETDEWEB)

    Romijn, I.G.; Van Aken, B.; Anker, J.; Barton, P.; Gutjahr, A.; Komatsu, Y.; Koppes, M.; Kossen, E.J.; Lamers, M.; Saynova, D.S.; Tool, C.J.J.; Zhang, Y. [ECN Solar Energy, P.O. Box 1, NL-1755 ZG Petten (Netherlands); Venema, P.R.; Vlooswijk, A.H.G. [Tempress Systems BV, Radeweg 31, 8171 MD Vaassen (Netherlands); Schmitt, C.; Kuehnlein, H.; Bay, N. [RENA GmbH, Hans-Bunte-Strasse 19, D-79108, Freiburg im Breisgau (Germany); Koenig, M.; Stassen, A.F. [Heraeus Precious Metals GmbH and Co. KG, Heraeusstrasse 12-14, D-63450, Hanau (Germany)

    2013-10-15

    The n-Pasha cell is a bifacial solar cell concept with average efficiencies between 19.8% and 20% and is optimized to enable high efficiencies with narrow distribution on wafers from the complete n-type ingots (2 to 10 {omega}-cm). This reduces the yield losses from a wafer point of view, which is important since the wafer costs make up the largest part ({approx}40%) of the total module costs for n-Pasha modules. The module fabrication itself adds up to {approx}35% of the module costs/Wp costs, which leaves {approx}25% of the costs/Wp for the cell production. We found that the costs/Wp for the 20% n-Pasha cell and module process are very similar to those of a 19% p-type cell, assuming similar wafer and module manufacturing costs. In the paper the successful implementation of a reduction of >60% in BBr{sub 3} consumption, and a reduction of >50% in Ag consumption are described, while keeping the n-Pasha cell efficiency at the same level. According to our calculations, the achieved reduction of the Ag and BBr{sub 3} consumption will lower the costs/Wp for n-Pasha modules below that of p-type. The majority of the efficiency losses in the n-Pasha cell are due to recombination in the diffused layers and below the contact regions. By tuning both the emitter and BSF profile, an efficiency gain of 0.4% absolute has been obtained. Based on the simulations and experimental results, the path towards further optimization and efficiencies approaching 21% is shown.

  19. Self Aligned Cell: Scaling Up Manufacture of a Cost Effective Cell Architecture for Multicrystalline Silicon Photovoltaics

    Energy Technology Data Exchange (ETDEWEB)

    Gabor, A.; van Mierlo, F.

    2010-12-01

    Two areas of technology for fabrication of higher efficiency Si-wafer solar cells were addressed: (1) the formation of structured texturing that is an improvement over the industry-standard isotexture process for multicrystalline wafers. (2) the formation of fine line (<50 micron) metallization seed layers in a self-aligned manner where the fingers can be automatically and perfectly lined up to a selective emitter and where expensive silver screen printing paste can be mostly replaced by plating up the seed layers with silver or copper. The benefits are: a) Lower reflectivity , b) Decoupling the performance of the texture from the saw damage, thus allowing for better advances in sawing and a more robust wet process. 1366 Technologies developed 2 pilot machines for 1) deposition and patterning of low-cost resist layers to enable simultaneous Honeycomb front texturing and groove formation for multicrystalline Si wafers, and 2) fine-line dispensing of materials that are self aligned to the grooves.

  20. LOW COST MULTI-LAYER FABRICATION METHOD FOR SOLID OXIDE FUEL CELLS

    Energy Technology Data Exchange (ETDEWEB)

    Christopher Milliken; Robert Ruhl; Jennifer Hillman

    2002-06-01

    Technology Management, Inc has evaluated the practical fabrication advantages and potential economic impact of a multi-pass screen printing process on the costs of fabricating planar solid oxide fuel cell stacks. During this program, multiple catalyzed binder systems were considered. Preliminary screening experiments resulted in four systems being selected for further evaluation. Inks were formulated using these binders in combination with at least three fuel cell materials (anode, cathode, and seal material). Reactivity of the binder with catalyst and fuel cell materials was evaluated. Cell tests indicated that the catalyzed binders did not negatively impact cell performance. Tests were conducted demonstrating single cell performance comparable with standard cell fabrication technology. Tailored patterns were also demonstrated. Economic evaluation indicated that a significant reduction in cost could be achieved, primarily through reduced capital equipment needs.

  1. Minimal Orderings Revisited

    Energy Technology Data Exchange (ETDEWEB)

    Peyton, B.W.

    1999-07-01

    When minimum orderings proved too difficult to deal with, Rose, Tarjan, and Leuker instead studied minimal orderings and how to compute them (Algorithmic aspects of vertex elimination on graphs, SIAM J. Comput., 5:266-283, 1976). This paper introduces an algorithm that is capable of computing much better minimal orderings much more efficiently than the algorithm in Rose et al. The new insight is a way to use certain structures and concepts from modern sparse Cholesky solvers to re-express one of the basic results in Rose et al. The new algorithm begins with any initial ordering and then refines it until a minimal ordering is obtained. it is simple to obtain high-quality low-cost minimal orderings by using fill-reducing heuristic orderings as initial orderings for the algorithm. We examine several such initial orderings in some detail.

  2. A Low Cost Rad-Tolerant Standard Cell Library

    Science.gov (United States)

    Gambles, Jody W.; Maki, Gary K.

    1997-01-01

    This paper describes circuit design techniques developed at the NASA Institute of Advanced Microelectronics that have been shown to protect CMOS circuits from the deleterious effects of the natural space radiation environment. The IAuE is leading a program to incorporate these radiation-tolerance providing design techniques into a commercial standard cell library that will be used in conjunction with available Electronic Design Automation tools to produce space flight qualified microelectronics fabricated at modern commercial CMOS foundries.

  3. Review of Back Contact Silicon Solar Cells for Low-Cost Application

    Energy Technology Data Exchange (ETDEWEB)

    Smith, David D.

    1999-08-04

    Back contact solar cells hold significant promise for increased performance in photovoltaics for the near future. Two major advantages which these cells possess are a lack of grid shading loss and coplanar interconnection. Front contacted cells can have up to 10% shading loss when using screen printed metal grids. A front contact cell must also use solder connections which run from the front of one cell to the back of the next for series interconnection. This procedure is more difficult to automate than the case of co-planar contacts. The back contact cell design is not a recent concept. The earliest silicon solar cell developed by Bell Labs was a back contact device. There have been many design modifications to the basic concept over the years. To name a few, there is the Interdigitated Back Contact (IBC) cell, the Stanford Point contact solar cell, the Emitter Wrap Through (EWT), and its many variations. A number of these design concepts have demonstrated high efficiency. The SunPower back contact solar cell holds the efficiency record for silicon concentrator cells. The challenge is to produce a high efficiency cell at low cost using high throughput techniques. This has yet to be achieved with a back contact cell design. The focus of this paper will be to review the relevant features of back contact cells and progress made toward the goal of a low cost version of this device.

  4. Sliver Solar Cells: High-Efficiency, Low-Cost PV Technology

    OpenAIRE

    2007-01-01

    Sliver cells are thin, single-crystal silicon solar cells fabricated using standard fabrication technology. Sliver modules, composed of several thousand individual Sliver cells, can be efficient, low-cost, bifacial, transparent, flexible, shadow tolerant, and lightweight. Compared with current PV technology, mature Sliver technology will need 10% of the pure silicon and fewer than 5% of the wafer starts per MW of factory output. This paper deals with two distinct challenges related to Sliver ...

  5. A New Model for Designing Cost Effective Zero Carbon Homes: Minimizing Commercial Viability Issues and Improving the Economics for Both the Developer and Purchaser

    Directory of Open Access Journals (Sweden)

    Rehan Khodabuccus

    2016-02-01

    Full Text Available There is a limited penetration of housing which offsets all operational carbon emissions within UK housing developer portfolios. This paper develops a balanced approach to zero carbon housing design from both architectural and national house builder perspectives. The paper discusses the techniques which can be used to reduce build costs, simplify designs and simplify renewable energy systems, resulting in more cost effective homes. The paper develops a technical and economic linked model to optimise a zero carbon design and then develops a home using this technique. It acknowledges that extra costs are inevitable but minimises them and details a lifecycle costing approach to provide economic justification. The paper then focuses on how the building designed can function more efficiently and economically than a Part L 2013 Building Regulation compliant building. Improved functionality is demonstrated both with and without the use of feed in tariffs. A key finding from this research is that zero carbon homes can benefit the consumer without impacting the developer. The results also demonstrate that homes could be better marketed on economic rather than environmental or technical attributes.

  6. Low cost delivery of proteins bioencapsulated in plant cells to human non-immune or immune modulatory cells.

    Science.gov (United States)

    Xiao, Yuhong; Kwon, Kwang-Chul; Hoffman, Brad E; Kamesh, Aditya; Jones, Noah T; Herzog, Roland W; Daniell, Henry

    2016-02-01

    Targeted oral delivery of GFP fused with a GM1 receptor binding protein (CTB) or human cell penetrating peptide (PTD) or dendritic cell peptide (DCpep) was investigated. Presence of GFP(+) intact plant cells between villi of ileum confirm their protection in the digestive system from acids/enzymes. Efficient delivery of GFP to gut-epithelial cells by PTD or CTB and to M cells by all these fusion tags confirm uptake of GFP in the small intestine. PTD fusion delivered GFP more efficiently to most tissues or organs than the other two tags. GFP was efficiently delivered to the liver by all fusion tags, likely through the gut-liver axis. In confocal imaging studies of human cell lines using purified GFP fused with different tags, GFP signal of DCpep-GFP was only detected within dendritic cells. PTD-GFP was only detected within kidney or pancreatic cells but not in immune modulatory cells (macrophages, dendritic, T, B, or mast cells). In contrast, CTB-GFP was detected in all tested cell types, confirming ubiquitous presence of GM1 receptors. Such low-cost oral delivery of protein drugs to sera, immune system or non-immune cells should dramatically lower their cost by elimination of prohibitively expensive fermentation, protein purification cold storage/transportation and increase patient compliance. PMID:26706477

  7. Cost and performance prospects for composite bipolar plates in fuel cells and redox flow batteries

    Science.gov (United States)

    Minke, Christine; Hickmann, Thorsten; dos Santos, Antonio R.; Kunz, Ulrich; Turek, Thomas

    2016-02-01

    Carbon-polymer-composite bipolar plates (BPP) are suitable for fuel cell and flow battery applications. The advantages of both components are combined in a product with high electrical conductivity and good processability in convenient polymer forming processes. In a comprehensive techno-economic analysis of materials and production processes cost factors are quantified. For the first time a technical cost model for BPP is set up with tight integration of material characterization measurements.

  8. Costs and Benefits of Stem Cell Research and Treatment: Media Presentation and Audience Understanding in Hungary

    OpenAIRE

    Vicsek, Lilla

    2011-01-01

    This study examined the press coverage and audience understanding of the costs and benefits of stem cell research/treatment in Hungary. A content analysis of five newspapers and a focus group study was conducted. The way participants talked about the costs and benefits in many aspects echoed the dominant framing of the issue in the press (medical benefits = main benefit, high expense of treatment = dominant negative aspect). Even though participants applied analogical reasoning to formulate s...

  9. Recommendations for the development of cost minimized combinations of renewable energies - elaborated for four types of model communities in North-Rhine Westphalia. 10. technical report

    International Nuclear Information System (INIS)

    The Tenth Technical Report of the study 'Analysis of Possibilities of Solar Power Supply and its Development in Nordrhein-Westfalen' contains a catalogue of recommended steps for the introduction of renewable energy systems into the existing energy supply structure in NRW. First, strategies for least cost renewable energy supply systems are developed and applied to modelled municipalities in such a way, that a cost optimized mix of renewable energies, depending on the desired degree of 'renewable coverage', can be given for each model community. Analogous to that, a low cost CO2-reduction strategy by an aimed extension of renewable energy systems is calculated and represented. The legal skeleton conditions of the power supply, information and training deficits as well as transmitted behavior patterns, which counteract an integration of renewable energy systems, are discussed in view of 'non economical' obstacles also. A catalogue of measures is presented, which contains informational, organizational and especially administrative aspects, including possibilities for governmental support. These recommendations may be used by those responsible for political decisions, i.e. by municipal planners, local or regional power suppliers and - last but not least - private consumers. (orig.)

  10. Low-cost multicrystalline silicon solar modules with 16% encapsulated cell efficiency

    Energy Technology Data Exchange (ETDEWEB)

    Verhoef, L.A.; Michiels, P.P.; Van Zolingen, R.J.C. [R and S Renewable Energy Systems, Helmond (Netherlands); De Moor, H.H.C.; Burgers, A.R.; Steeman, R.A.; Sinke, W.C. [ECN Renewable Energy, Petten (Netherlands)

    1994-12-01

    A production process for multicrystalline silicon solar cells has been developed. The technology, involving screen printing and large volume batch processing, is simple and contains cost-effective processing steps. A module consisting of 36 cells, each 100 cm{sup 2} area, generates a peak power of 56.5 W under standard test conditions (global AM 1.5, 25C, 1000 W/m{sup 2}). This corresponds to an encapsulated cell efficiency of 15.7%. The cell to cell standard deviation is less than 0.3%. Key factors in reaching these high efficiencies are embedded in cell processing and module fabrication. The cell processing employs bulk passivation, gettering, selective emitter surface passivation, reduced metal coverage and improved optical matching of cell and module. The module is fabricated with improved module lay-up and interconnection geometry. 2 tabs., 14 refs.

  11. Low-cost multicrystalline silicon solar modules with 16% encapsulated cell efficiency

    Energy Technology Data Exchange (ETDEWEB)

    Verhoef, L.A.; Michiels, P.P.; Zolingen, R.J.C. van [R and S Renewable Energy Systems B.V., Helmond (Netherlands); Moor, H.H.C. de; Burgers, A.R.; Steeman, R.A.; Sinke, W.C. [Netherlands Energy Research Foundation ECN, Petten (Netherlands)

    1994-12-31

    A production process for multicrystalline silicon solar cells has been developed. The technology, involving screen printing and large volume batch processing, is simple and contains cost-effective processing steps. A module consisting of 36 cells, each 100 cm{sup 2} area, generates a peak power of 56.5 W under standard test conditions global AM 1.5, 25 C, 1,000 W/m{sup 2}. This corresponds to an encapsulated cell efficiency of 15.7%. The cell to cell standard deviation is less than 0.3%. Key factors in reaching these high efficiencies are embedded in cell processing and module fabrication. The cell processing employs bulk passivation, gettering, selective emitter surface passivation, reduced metal coverage and improved optical matching of cell and module. The module is fabricated with improved module lay-up and interconnection geometry.

  12. Photovoltaic solar cell from low-cost thin-film technology

    International Nuclear Information System (INIS)

    Full text : One of the main hindrances of using solar energy for electrical power supply is the high initial cost. Thin-film technologies hold considerable promise for substantial cost reduction for photovoltaic solar cells. The paper reviews the present state of the most advanced thin-film technologies. Amorphous silicon solar cells have surmounted the barrier to mass production. Pilot manufacturing lines are under construcion for CdTe thin-film module. Cu(In, Ga)Se2 has reached a record efficiency of 18.8 percent in the laboratory and pilot productions have benn announced by various companies

  13. Photovoltaic solar cell from low-cost thin-film technology

    International Nuclear Information System (INIS)

    One of the main hindrances of using solar energy for electrical power supply is the high initial cost. Thin-film technologies hold considerable promise for substantial cost reduction for photovoltaic solar cells. The paper reviews the present state of the most advanced thin-film technologies. Amorphous silicon (a-Si:H) solar cells have surmounted the barrier to mass production. Pilot manufacturing lines are under construction for CdTe thin-film module. Cu(In, Ga)Se2 has reached a record efficiency of 18.8 percent in the laboratory and pilot productions have been announced by various companies

  14. Low-cost multicrystalline back-contact silicon solar cells with screen printed metallization

    International Nuclear Information System (INIS)

    Adaptation to market requirements is a permanent challenge in industrial solar-cell production. Both increase of cell efficiency as well as lowering costs is demanded. Back-contacted solar cells offer multiple advantages in terms of reducing module assembling costs and enhanced cell efficiency. The investigated emitter-wrap-through (EWT) design [1] has a collecting emitter on front and rear side. These emitter areas are electrically connected by small holes. Due to the double-sided collecting junction, this cell design is favourable for materials with a low-minority charge carrier diffusion length leading to a higher short circuit current density. Until now most investigations on EWT solar cells were performed on Cz or even FZ silicon. This was justified as long as different processing techniques had to be developed and compared. But as an industrially applicable process sequence has recently been developed [2], the advantages of the EWT concept compared to conventionally processed cells have to be shown on multicrystalline material. In the following, a manufacturing process of EWT solar cells is presented which is especially adapted to the requirements of multicrystalline silicon. Effective surface texturization was reached by mechanical V-texturization and bulk passivation by a hydrogen plasma treatment. The efficiency of the best solar cells within this process reached 14.2% which is the highest efficiency reported so far for mc-Si 10x10 cm2 EWT solar cells [3]. (author)

  15. Motivation for a near term gun launch to space demonstration and a variable induction power supply concept to minimize initial demonstration costs

    International Nuclear Information System (INIS)

    The history of the Gun Launch to Space (GLTS) concept is briefly reviewed along with recent progress and motivations for a near term launch demonstration. A current multiplying reconfigurable inductor design is developed which could couple to an existing battery system to power a GLTS railgun demonstration at the 300 megajoule muzzle energy level. The design is developed using proven approaches and performance levels and appears capable of reducing the power supply cost for an initial GLTS demonstration below that of a simple battery charged inductor system. Possible uses are (1) launching of space weapons; (2) launching of communication satellites; (3) and launching of satellites for space disposal of radioactive wastes

  16. Large area, low cost space solar cells with optional wraparound contacts

    Science.gov (United States)

    Michaels, D.; Mendoza, N.; Williams, R.

    1981-01-01

    Design parameters for two large area, low cost solar cells are presented, and electron irradiation testing, thermal alpha testing, and cell processing are discussed. The devices are a 2 ohm-cm base resistivity silicon cell with an evaporated aluminum reflector produced in a dielectric wraparound cell, and a 10 ohm-cm silicon cell with the BSF/BSR combination and a conventional contact system. Both cells are 5.9 x 5.9 cm and require 200 micron thick silicon material due to mission weight constraints. Normalized values for open circuit voltage, short circuit current, and maximum power calculations derived from electron radiation testing are given. In addition, thermal alpha testing values of absorptivity and emittance are included. A pilot cell processing run produced cells averaging 14.4% efficiencies at AMO 28 C. Manufacturing for such cells will be on a mechanized process line, and the area of coverslide application technology must be considered in order to achieve cost effective production.

  17. A cost-effective system for differentiation of intestinal epithelium from human induced pluripotent stem cells

    OpenAIRE

    Soichiro Ogaki; Mayu Morooka; Kaito Otera; Shoen Kume

    2015-01-01

    The human intestinal epithelium is a useful model for pharmacological studies of absorption, metabolism, drug interactions, and toxicology, as well as for studies of developmental biology. We established a rapid and cost effective system for differentiation of human induced pluripotent stem (iPS) cells into definitive endoderm (DE) cells. In the presence of dimethyl sulfoxide (DMSO), a low concentration of Activin at 6.25 ng/ml is sufficient to give a similar differentiation efficiency with t...

  18. Assembly of a Cost-Effective Anode Using Palladium Nanoparticles for Alkaline Fuel Cell Applications

    OpenAIRE

    Feliciano-Ramos, Ileana; Casañas-Montes, Barbara; García-Maldonado, María M.; Menéndez, Christian L.; Mayol, Ana R.; Díaz-Vázquez, Liz M.; Cabrera, Carlos R.

    2014-01-01

    Nanotechnology allows the synthesis of nanoscale catalysts, which offer an efficient alternative for fuel cell applications. In this laboratory experiment, the student selects a cost-effective anode for fuel cells by comparing three different working electrodes. These are commercially available palladium (Pd) and glassy carbon (GC) electrodes, and a carbon paste (CP) electrode that is prepared by the students in the laboratory. The GC and CP were modified with palladium nanoparticles (PdNP) s...

  19. Optimization of the front contact to minimize short-circuit current losses in CdTe thin-film solar cells

    Science.gov (United States)

    Kephart, Jason Michael

    With a growing population and rising standard of living, the world is in need of clean sources of energy at low cost in order to meet both economic and environmental needs. Solar energy is an abundant resource which is fundamentally adequate to meet all human energy needs. Photovoltaics are an attractive way to safely convert this energy to electricity with little to no noise, moving parts, water, or arable land. Currently, thin-film photovoltaic modules based on cadmium telluride are a low-cost solution with multiple GW/year commercial production, but have lower conversion efficiency than the dominant technology, crystalline silicon. Increasing the conversion efficiency of these panels through optimization of the electronic and optical structure of the cell can further lower the cost of these modules. The front contact of the CdTe thin-film solar cell is critical to device efficiency for three important reasons: it must transmit light to the CdTe absorber to be collected, it must form a reasonably passive interface and serve as a growth template for the CdTe, and it must allow electrons to be extracted from the CdTe. The current standard window layer material, cadmium sulfide, has a low bandgap of 2.4 eV which can block over 20% of available light from being converted to mobile charge carriers. Reducing the thickness of this layer or replacing it with a higher-bandgap material can provide a commensurate increase in device efficiency. When the CdS window is made thinner, a degradation in electronic quality of the device is observed with a reduction in open-circuit voltage and fill factor. One commonly used method to enable a thinner optimum CdS thickness is a high-resistance transparent (HRT) layer between the transparent conducting oxide electrode and window layer. The function of this layer has not been fully explained in the literature, and existing hypotheses center on the existence of pinholes in the window layer which are not consistent with observed results

  20. U.S. DOE Progress Towards Developing Low-Cost, High Performance, Durable Polymer Electrolyte Membranes for Fuel Cell Applications

    OpenAIRE

    Dimitrios C. Papageorgopoulos; Reginald Tyler; Jason Marcinkoski; Kathi Epping Martin; Donna Lee Ho; Garland, Nancy L.; David Peterson; John Kopasz; Spendelow, Jacob S.; Greg J. Kleen; Cassidy Houchins

    2012-01-01

    Low cost, durable, and selective membranes with high ionic conductivity are a priority need for wide-spread adoption of polymer electrolyte membrane fuel cells (PEMFCs) and direct methanol fuel cells (DMFCs). Electrolyte membranes are a major cost component of PEMFC stacks at low production volumes. PEMFC membranes also impose limitations on fuel cell system operating conditions that add system complexity and cost. Reactant gas and fuel permeation through the membrane leads to decreased fuel ...

  1. Papers of the Canadian Institute conference on buying power in Ontario : critical starting-gate information evolving strategies to reduce costs and minimize risk

    International Nuclear Information System (INIS)

    Industry executives and senior government officials attended this conference to learn what to expect when the electricity market opens in Ontario. Topics of discussion included the new risks as well as hedging strategies to manage volatile electricity prices. Papers presented a status update regarding what services to expect from utilities and marketers in a deregulated market. Several presentations described Alberta's experience with deregulation and presented lessons that Ontario can learn to save time, money and how to best deal with electricity contracts. Methods to control and monitor energy consumption and energy costs internally were also described. A total of 14 papers were presented, of which 4 were indexed separately for inclusion in the database. tabs., figs

  2. Minimizing the time and cost of production of transgenic alfalfa libraries using the highly efficient completely sequenced vector pPZP200BAR.

    Science.gov (United States)

    Jozefkowicz, Cintia; Bottero, Emilia; Pascuan, Cecilia; Pagano, Elba; Ayub, Nicolás Daniel; Soto, Gabriela

    2016-09-01

    Alfalfa is the most important forage legume worldwide. However, similar to other minor forage crops, it is usually harvested along with weeds, which decrease its nutrient quality and thus reduce its high value in the market. In addition, weeds reduce alfalfa yield by about 50 %. Although weeds are the limiting factor for alfalfa production, little progress has been made in the incorporation of herbicide-tolerant traits into commercial alfalfa. This is partially due to the high times and costs needed for the production of vast numbers of transgenic alfalfa events as an empirical approach to bypass the random transgenic silencing and for the identification of an event with optimal transgene expression. In this focus article, we report the complete sequence of pPZP200BAR and the extremely high efficiency of this binary vector in alfalfa transformation, opening the way for rapid and inexpensive production of transgenic events for alfalfa improvement public programs. PMID:27447893

  3. Cost effective n-Pasha solar cells with efficiency above 20%

    Energy Technology Data Exchange (ETDEWEB)

    Romijn, I.G.; Gutjahr, A.; Saynova-Oosterling, D.S.; Anker, J.; Kossen, E.J.; Tool, C.J.J. [ECN Solar Energy, Petten (Netherlands)

    2013-05-15

    This paper presents recent developments of ECN's n-Pasha (passivated on all sides H-pattern) solar cell technology. The n-Pasha cell, currently being produced on an industrial scale by Yingli Solar, is a solar cell fabricated on n-type Cz material with homogeneous diffusions, dielectric passivation and printed metallization on both sides. The metallization is applied in an open H-pattern to both sides, which makes it suitable for bifacial applications. In order to improve both cell performance and the cost of ownership of n-Pasha solar cells, the ECN R and D team has focused on several aspects of the device design and processing. By reducing metal coverage and improving the quality of the front-side metallization, tuning the back-surface field (BSF) doping and improving the front- and rear-surface passivation, it has been possible to obtain an average efficiency of 20%, with top efficiencies of 20.2%. At the same time, the amount of silver used for metallization has been decreased by over 50% and is now similar to that used for p-type solar cells. Furthermore, it is shown that with the ECN n-Pasha cell concept, wafers from the full resistivity range of n-Cz ingots can be used to make cells without losses in efficiency. Combining the improved efficiency and the reduction in cost makes the n-Pasha cell concept a very cost-effective solution for manufacturing highly efficient solar cells and modules.

  4. Recombinant versus highly-purified, urinary follicle-stimulating hormone (r-FSH vs. HP-uFSH in ovulation induction: a prospective, randomized study with cost-minimization analysis

    Directory of Open Access Journals (Sweden)

    Grassi Giuseppina

    2006-07-01

    Full Text Available Abstract Background Both recombinant FSH (r-FSH and highly-purified, urinary FSH (HP-uFSH are frequently used in ovulation induction associated with timed sexual intercourse. Their effectiveness is reported to be similar, and therefore the costs of treatment represent a major issue to be considered. Although several studies about costs in IVF have been published, data obtained in low-technology infertility treatments are still scarce. Methods Two hundred and sixty infertile women (184 with unexplained infertility, 76 with CC-resistant polycystic ovary syndrome at their first treatment cycle were randomized and included in the study. Ovulation induction was accomplished by daily administration of rFSH or HP-uFSH according to a low-dose, step-up regimen aimed to obtain a monofollicular ovulation. A bi- or tri-follicular ovulation was anyway accepted, whereas hCG was withdrawn and the cycle cancelled when more than three follicles greater than or equal to 18 mm diameter were seen at ultrasound. The primary outcome measure was the cost of therapy per delivered baby, estimated according to a cost-minimization analysis. Secondary outcomes were the following: monofollicular ovulation rate, total FSH dose, cycle cancellation rate, length of the follicular phase, number of developing follicles (>12 mm diameter, endometrial thickness at hCG, incidence of twinning and ovarian hyperstimulation syndrome, delivery rate. Results The overall FSH dose needed to achieve ovulation was significantly lower with r-FSH, whereas all the other studied variables did not significantly differ with either treatments. However, a trend toward a higher delivery rate with r-FSH was observed in the whole group and also when results were considered subgrouping patients according to the indication to treatment. Conclusion Considering the significantly lower number of vials/patient and the slight (although non-significant increase in the delivery rate with r-FSH, the cost-minimization

  5. Re: Fibrin Glue Injections: A Minimally Invasive and Cost-Effective Treatment for Post-Renal Transplant Lymphoceles and Lymph Fistulas

    Directory of Open Access Journals (Sweden)

    Presser N

    2016-03-01

    Full Text Available In this retrospective study, 46 (2.7% patients out of 1662 kidney transplant recipients had developed symptomatic lymphocele/lymph fistula requiring intervention over an 11-year period. Open surgical drainage (22, laparoscopic surgical drainage (11 and percutaneous fibrin glue injections into the drained lymphocele cavity (13 were used to treat this complication. Besides being effective both on the early and late developed lymphoceles, significantly lower recurrence rates by fibrin glue injections and lower median treatment costs were observed when compared with the other two surgical modalities. It has also the advantage of an outpatient procedure that can be performed using fluoroscopic guidance, under local anesthesia. However, due to era effect, most of the open and laparoscopic surgical recipients were treated with sirolimus, a well-known antiproliferative immunosuppressive agent, which can promote development of lymphoceles and surgical failure. However, the majority of fibrin glue-treated cases were with tacrolimus-based regimens, but this study, in its nature, is far from giving the answer for decreased number of recurrences with fibrin glue

  6. A New, Scalable and Low Cost Multi-Channel Monitoring System for Polymer Electrolyte Fuel Cells.

    Science.gov (United States)

    Calderón, Antonio José; González, Isaías; Calderón, Manuel; Segura, Francisca; Andújar, José Manuel

    2016-01-01

    In this work a new, scalable and low cost multi-channel monitoring system for Polymer Electrolyte Fuel Cells (PEFCs) has been designed, constructed and experimentally validated. This developed monitoring system performs non-intrusive voltage measurement of each individual cell of a PEFC stack and it is scalable, in the sense that it is capable to carry out measurements in stacks from 1 to 120 cells (from watts to kilowatts). The developed system comprises two main subsystems: hardware devoted to data acquisition (DAQ) and software devoted to real-time monitoring. The DAQ subsystem is based on the low-cost open-source platform Arduino and the real-time monitoring subsystem has been developed using the high-level graphical language NI LabVIEW. Such integration can be considered a novelty in scientific literature for PEFC monitoring systems. An original amplifying and multiplexing board has been designed to increase the Arduino input port availability. Data storage and real-time monitoring have been performed with an easy-to-use interface. Graphical and numerical visualization allows a continuous tracking of cell voltage. Scalability, flexibility, easy-to-use, versatility and low cost are the main features of the proposed approach. The system is described and experimental results are presented. These results demonstrate its suitability to monitor the voltage in a PEFC at cell level. PMID:27005630

  7. A New, Scalable and Low Cost Multi-Channel Monitoring System for Polymer Electrolyte Fuel Cells

    Directory of Open Access Journals (Sweden)

    Antonio José Calderón

    2016-03-01

    Full Text Available In this work a new, scalable and low cost multi-channel monitoring system for Polymer Electrolyte Fuel Cells (PEFCs has been designed, constructed and experimentally validated. This developed monitoring system performs non-intrusive voltage measurement of each individual cell of a PEFC stack and it is scalable, in the sense that it is capable to carry out measurements in stacks from 1 to 120 cells (from watts to kilowatts. The developed system comprises two main subsystems: hardware devoted to data acquisition (DAQ and software devoted to real-time monitoring. The DAQ subsystem is based on the low-cost open-source platform Arduino and the real-time monitoring subsystem has been developed using the high-level graphical language NI LabVIEW. Such integration can be considered a novelty in scientific literature for PEFC monitoring systems. An original amplifying and multiplexing board has been designed to increase the Arduino input port availability. Data storage and real-time monitoring have been performed with an easy-to-use interface. Graphical and numerical visualization allows a continuous tracking of cell voltage. Scalability, flexibility, easy-to-use, versatility and low cost are the main features of the proposed approach. The system is described and experimental results are presented. These results demonstrate its suitability to monitor the voltage in a PEFC at cell level.

  8. Minimal leptogenesis

    CERN Document Server

    Hamada, Yuta

    2015-01-01

    We propose a novel leptogenesis scenario at the reheating era. Our setup is minimal in the sense that, in addition to the standard model Lagrangian, we only consider an inflaton and higher dimensional operators. The lepton number asymmetry is produced not by the decay of a heavy particle, but by the scattering between the standard model particles. After the decay of an inflaton, the model is described within the standard model with higher dimensional operators. The Sakharov's three conditions are satisfied by the following way. The violation of the lepton number is realized by the dimension-5 operator. The complex phase comes from the dimension-6 four lepton operator. The universe is out of equilibrium before the reheating is completed. It is found that the successful baryogenesis is realized for the wide range of parameters, the inflaton mass and reheating temperature, depending on the cutoff scale. Since we only rely on the effective Lagrangian, our scenario can be applicable to all mechanisms to generate n...

  9. Minimal cosmography

    CERN Document Server

    Piazza, Federico

    2015-01-01

    The minimal requirement for cosmography - a nondynamical description of the universe - is a prescription for calculating null geodesics, and timelike geodesics as a function of their proper time. In this paper, we consider the most general linear connection compatible with homogeneity and isotropy, but not necessarily with a metric. A light-cone structure is assigned by choosing a set of geodesics representing light rays. This defines a "scale factor" and a local notion of distance, as that travelled by light in a given proper time interval. We find that the velocities and relativistic energies of free-falling bodies decrease in time as a consequence of cosmic expansion, but at a rate that can be different than that dictated by the usual metric framework. By extrapolating this behavior to photons redshift, we find that the latter is in principle independent of the "scale factor". Interestingly, redshift-distance relations and other standard geometric observables are modified in this extended framework, in a w...

  10. Minimal cosmography

    Science.gov (United States)

    Piazza, Federico; Schücker, Thomas

    2016-04-01

    The minimal requirement for cosmography—a non-dynamical description of the universe—is a prescription for calculating null geodesics, and time-like geodesics as a function of their proper time. In this paper, we consider the most general linear connection compatible with homogeneity and isotropy, but not necessarily with a metric. A light-cone structure is assigned by choosing a set of geodesics representing light rays. This defines a "scale factor" and a local notion of distance, as that travelled by light in a given proper time interval. We find that the velocities and relativistic energies of free-falling bodies decrease in time as a consequence of cosmic expansion, but at a rate that can be different than that dictated by the usual metric framework. By extrapolating this behavior to photons' redshift, we find that the latter is in principle independent of the "scale factor". Interestingly, redshift-distance relations and other standard geometric observables are modified in this extended framework, in a way that could be experimentally tested. An extremely tight constraint on the model, however, is represented by the blackbody-ness of the cosmic microwave background. Finally, as a check, we also consider the effects of a non-metric connection in a different set-up, namely, that of a static, spherically symmetric spacetime.

  11. Cost and effectiveness studies in non-small cell lung cancer

    Directory of Open Access Journals (Sweden)

    Pinar Yalcin-Balcik

    2015-02-01

    Full Text Available Lung cancer disease diagnosis and treatment is costly. As the numbers of inflicted rise so does the economic burden assumed for this cancer type. When the treatment expenditures are considered for all types of cancer, the lung cancer is thought to occupy a 20% share. The disease examined in two basic groups as small-cell lung cancer and non-small cell lung cancer (NSCLC is the most frequently encountered type of its kind nationally and in the World. This study considers the cost, effectiveness and cost effectiveness of platinum based chemotherapy medications with active ingredients pemetrexed and gemcitabine used for NSCLC. A review of studies relevant to the advanced stage NSCLC where majority of patients are positioned is foreseen to be useful to the decision makers since policy makers, regulating authorities and physicians require more information due to increased overall finance and costs, as well as treatment cost effectiveness. Furthermore, due to the entry attempt of pemetrexed active ingredient to the list of reimbursed medications for the first stage lung cancer treatment, it is assumed that a review of studies containing pemetrexed and gemcitabine will draw the attention of decision makers at the Social Security Instutition. [TAF Prev Med Bull 2015; 14(1.000: 55-64

  12. Cost comparison of second-line treatment options for late stage non-small-cell lung cancer: cost analysis for Italy

    Directory of Open Access Journals (Sweden)

    Schwander B

    2012-09-01

    Full Text Available Bjoern Schwander,1 Simona Ravera,2 Giovanni Giuliani,2 Mark Nuijten,3 Stefan Walzer11Assessment-in-Medicine (AiM GmbH, Loerrach, Germany; 2Roche SpA, Monza, Italy; 3Ars Accessus Medica, Amsterdam (Jisp, NetherlandsBackground: Lung cancer is the leading cause of cancer deaths worldwide (1.38 million cancer deaths, 18.2% of the total and of cancer morbidity (1.61 million new cases, 12.7% of all new cancers. Currently only three second-line non-small-cell lung cancer (NSCLC pharmacotherapies are licensed in the European Union: the chemotherapies pemetrexed and docetaxel and the epidermal growth factor receptor tyrosine kinase inhibitor erlotinib. These therapy alternatives have shown a comparable efficacy (survival benefit. In the past, cost comparisons showed that erlotinib was less costly compared to docetaxel, which in turn is cheaper than pemetrexed. Nowadays erlotinib (and docetaxel are still less expensive than pemetrexed; but docetaxel lost patent protection (basic compound patent at the end of 2010, so docetaxel drug costs have decreased rapidly and the question remains whether erlotinib is still the least costly therapy alternative in second-line NSCLC.Material and methods: Italy was selected for base case analysis to compare the total therapy costs, estimated by combining country-specific drug costs, administration costs, and adverse event costs of erlotinib and generic docetaxel in second-line NSCLC therapy. Sensitivity analyses on central input parameters have been performed.Results: The total costs of treating one patient with erlotinib therapy of €5121 are lower than the docetaxel costs of €6699 for the Italian health care setting. Although the drug costs of erlotinib are higher than generic docetaxel (incremental €3770: the costs of intravenous chemotherapy administration (incremental -€4510, and the costs of adverse event therapy (incremental -€837 lead to higher total therapy costs for docetaxel compared to the epidermal

  13. Automotive Lithium-ion Cell Manufacturing: Regional Cost Structures and Supply Chain Considerations

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Donald [Clean Energy Manufacturing Analysis Center, Godlen, CO (United States); Elgqvist, Emma [Clean Energy Manufacturing Analysis Center, Godlen, CO (United States); Santhanagopalan, Shriram [Clean Energy Manufacturing Analysis Center, Godlen, CO (United States)

    2016-04-08

    Manufacturing capacity for lithium-ion batteries (LIBs)--which power many consumer electronics and are increasingly used to power electric vehicles--is heavily concentrated in east Asia. Currently, China, Japan, and Korea collectively host 88% of all LIB cell and 79% of automotive LIB cell manufacturing capacity. Mature supply chains and strong cumulative production experience suggest that most LIB cell production will remain concentrated in Asia. However, other regions--including North America--could be competitive in the growing automotive LIB cell market under certain conditions. To illuminate the factors that drive regional competitiveness in automotive LIB cell production, this study models cell manufacturing cost and minimum sustainable price, and examines development of LIB supply chains and current LIB market conditions. Modeled costs are for large format, 20-Ah stacked pouch cells with lithium-nickel-manganese-cobalt-oxide (NMC) cathodes and graphite anodes suitable for automotive application. Production volume is assumed to be at commercial scale, 600 MWh per year.

  14. Manufacturing Cost Analysis for YSZ-Based FlexCells at Pilot and Full Scale Production Scales

    Energy Technology Data Exchange (ETDEWEB)

    Scott Swartz; Lora Thrun; Robin Kimbrell; Kellie Chenault

    2011-05-01

    Significant reductions in cell costs must be achieved in order to realize the full commercial potential of megawatt-scale SOFC power systems. The FlexCell designed by NexTech Materials is a scalable SOFC technology that offers particular advantages over competitive technologies. In this updated topical report, NexTech analyzes its FlexCell design and fabrication process to establish manufacturing costs at both pilot scale (10 MW/year) and full-scale (250 MW/year) production levels and benchmarks this against estimated anode supported cell costs at the 250 MW scale. This analysis will show that even with conservative assumptions for yield, materials usage, and cell power density, a cost of $35 per kilowatt can be achieved at high volume. Through advancements in cell size and membrane thickness, NexTech has identified paths for achieving cell manufacturing costs as low as $27 per kilowatt for its FlexCell technology. Also in this report, NexTech analyzes the impact of raw material costs on cell cost, showing the significant increases that result if target raw material costs cannot be achieved at this volume.

  15. Off-pump or minimized on-pump coronary surgery - initial experience with Circulating Endothelial Cells (CEC) as a supersensitive marker of tissue damage

    OpenAIRE

    Wittwer Thorsten; Choi Yeong-Hoon; Neef Klaus; Schink Mareike; Sabashnikov Anton; Wahlers Thorsten

    2011-01-01

    Abstract Background Off-pump-coronary-artery-bypass-grafting (OPCAB) and minimized-extracorporeal-circulation (Mini-HLM) have been proposed to avoid harmful effects of cardiopulmonary-bypass (CPB). Controversies exist whether OPCAB is still superior in perioperative outcome. Circulating endothelial cells (CEC) are sensitive markers of endothelial damage and are significantly elevated in conventional-CPB-procedures as compared to Mini-HLM-revascularisation. Therefore, CEC might be of specific ...

  16. To Minimize the Waiting Time and Waiting Time Cost of Dumpers, Waiting in a Queue for Loader at Stone Crusher Plant Mine by Using the Single and Multi-Channel Queuing Theory.

    Directory of Open Access Journals (Sweden)

    Vaibhav Singh

    2014-09-01

    Full Text Available Waiting line problems arise because there is too much demand on the facilities so that we can say that there is an excess of waiting time or inadequate number of service facilities. At the stone crusher plant mine the dumpers come to load from the loader. The crusher plant has 11 dumpers and these 11 dumpers make 88 trips during 8-hour day. The company has one loader to load all the dumpers, which results in a formation of long waiting line or queue. Due to this queue there is a long waiting time in queue of dumpers and cost associated with waiting time of dumpers. Queuing theory can quite effectively analyze such queuing phenomenon. In this research paper I have applied the queuing theory to the stone crusher plant mine, where the queue of dumpers formed at the loading station. By applying the single channel queuing theory I analyzed the current situation of the stone crusher plant mine and find the problems of the current system. To overcome the above problems I have applied the multi-channel queuing theory to minimize the waiting time in queue of dumpers and very high cost associated with waiting time of dumpers. In the new system not only waiting time in queue of dumpers and very high cost associated with waiting time of dumpers is reduced but also there is an efficient utilization of dumpers and loaders along with provide the profitable situation to the crusher plant.

  17. Minimally Invasive Dentistry

    Science.gov (United States)

    ... to your desktop! more... What Is Minimally Invasive Dentistry? Article Chapters What Is Minimally Invasive Dentistry? Minimally ... techniques. Reviewed: January 2012 Related Articles: Minimally Invasive Dentistry Minimally Invasive Veneers Dramatically Change Smiles What Patients ...

  18. Optical cell tracking analysis using a straight-forward approach to minimize processing time for high frame rate data

    Science.gov (United States)

    Seeto, Wen Jun; Lipke, Elizabeth Ann

    2016-03-01

    Tracking of rolling cells via in vitro experiment is now commonly performed using customized computer programs. In most cases, two critical challenges continue to limit analysis of cell rolling data: long computation times due to the complexity of tracking algorithms and difficulty in accurately correlating a given cell with itself from one frame to the next, which is typically due to errors caused by cells that either come close in proximity to each other or come in contact with each other. In this paper, we have developed a sophisticated, yet simple and highly effective, rolling cell tracking system to address these two critical problems. This optical cell tracking analysis (OCTA) system first employs ImageJ for cell identification in each frame of a cell rolling video. A custom MATLAB code was written to use the geometric and positional information of all cells as the primary parameters for matching each individual cell with itself between consecutive frames and to avoid errors when tracking cells that come within close proximity to one another. Once the cells are matched, rolling velocity can be obtained for further analysis. The use of ImageJ for cell identification eliminates the need for high level MATLAB image processing knowledge. As a result, only fundamental MATLAB syntax is necessary for cell matching. OCTA has been implemented in the tracking of endothelial colony forming cell (ECFC) rolling under shear. The processing time needed to obtain tracked cell data from a 2 min ECFC rolling video recorded at 70 frames per second with a total of over 8000 frames is less than 6 min using a computer with an Intel® Core™ i7 CPU 2.80 GHz (8 CPUs). This cell tracking system benefits cell rolling analysis by substantially reducing the time required for post-acquisition data processing of high frame rate video recordings and preventing tracking errors when individual cells come in close proximity to one another.

  19. Mass Production Cost Estimation For Direct H2 PEM Fuel Cell Systesm for Automotive Applications. 2010 Update

    Energy Technology Data Exchange (ETDEWEB)

    James, Brian D. [Directed Technologies, Arlington, VA (United States); Kalinoski, Jeffrey A. [Directed Technologies, Arlington, VA (United States); Baum, Kevin N. [Directed Technologies, Arlington, VA (United States)

    2010-09-30

    This report is the fourth annual update of a comprehensive automotive fuel cell cost analysis. It contains estimates for material and manufacturing costs of complete 80 kWnet direct-hydrogen proton exchange membrane fuel cell systems suitable for powering light-duty automobiles.

  20. Mass Production Cost Estimation for Direct H2 PEM Fuel Cell Systems for Automotive Applications. 2009 Update

    Energy Technology Data Exchange (ETDEWEB)

    James, Brian D. [Directed Technologies, Arlington, VA (United States); Kalinoski, Jeffrey A. [Directed Technologies, Arlington, VA (United States); Baum, Kevin N. [Directed Technologies, Arlington, VA (United States)

    2010-01-01

    This report is the third annual update of a comprehensive automotive fuel cell cost analysis. It contains estimates for material and manufacturing cost of complete 80 kWnet direct hydrogen proton exchange membrane fuel cell systems suitable for powering light duty automobiles.

  1. The cost of hematopoietic stem cell transplantation in the real world.

    Science.gov (United States)

    Seber, Adriana

    2012-04-01

    In Brazil, the majority of the population does not have private health insurance and the government provides universal health care. Our 'Unique Healthcare System' pays for 95% of the 1500 hematopoietic stem cell transplants (HSCT) performed in the country every year. Hospitals are reimbursed a flat rate, ranging from US$ 13,000 for autologous to US$ 40,500 for unrelated donor transplants, excluding expenses with donor search and acquisition of the graft. The actual cost of the procedure is not captured routinely. Because unrelated donor recipients may have many clinical complications, most HSCT centers offer few or no beds to perform such transplants. The Pediatric Oncology Institute - GRAACC - is a non-profit organization that provides comprehensive care at no cost to the families, including unrelated donor HSCT. We are evaluating retrospectively the unrelated donor transplant costs to have data to present to the health authorities, looking for an appropriate funding formula for HSCT. PMID:22507822

  2. Cost Study for Manufacturing of Solid Oxide Fuel Cell Power Systems

    Energy Technology Data Exchange (ETDEWEB)

    Weimar, Mark R.; Chick, Lawrence A.; Gotthold, David W.; Whyatt, Greg A.

    2013-09-30

    Solid oxide fuel cell (SOFC) power systems can be designed to produce electricity from fossil fuels at extremely high net efficiencies, approaching 70%. However, in order to penetrate commercial markets to an extent that significantly impacts world fuel consumption, their cost will need to be competitive with alternative generating systems, such as gas turbines. This report discusses a cost model developed at PNNL to estimate the manufacturing cost of SOFC power systems sized for ground-based distributed generation. The power system design was developed at PNNL in a study on the feasibility of using SOFC power systems on more electric aircraft to replace the main engine-mounted electrical generators [Whyatt and Chick, 2012]. We chose to study that design because the projected efficiency was high (70%) and the generating capacity was suitable for ground-based distributed generation (270 kW).

  3. The Costs and Cost-Effectiveness of Allogeneic Peripheral Blood Stem Cell Transplantation versus Bone Marrow Transplantation in Pediatric Patients with Acute Leukemia

    OpenAIRE

    LIN Yu-feng; Lairson, David R.; Chan, Wenyaw; Du, Xianglin L.; Leung, Kathryn S.; Kennedy-Nasser, Alana A.; Martinez, Caridad A; Gottschalk, Stephen M; Bollard, Catherine M.; Heslop, Helen E.; Brenner, Malcolm K; Krance, Robert A.

    2010-01-01

    In a retrospective study, we evaluated the cost and cost-effectiveness of allogeneic peripheral blood stem cell transplantation (PBSCT) (n=30) compared with bone marrow transplantation (BMT) (n=110) in children with acute leukemia at 1 year of follow up. Treatment success was defined as disease free survival at one year post transplant. For standard risk disease patients the treatment success rate was 57.1% for PBSCT patients and 80.3% for recipients of BMT (P=NS). The average total cost per ...

  4. Targeting the expression of glutathione- and sulfate-dependent detoxification enzymes in HepG2 cells by oxygen in minimal and amino acid enriched medium.

    Science.gov (United States)

    Usarek, Ewa; Graboń, Wojciech; Kaźmierczak, Beata; Barańczyk-Kuźma, Anna

    2016-02-01

    Cancer cells exhibit specific metabolism allowing them to survive and proliferate in various oxygen conditions and nutrients' availability. Hepatocytes are highly active metabolically and thus very sensitive to hypoxia. The purpose of the study was to investigate the effect of oxygen on the expression of phase II detoxification enzymes in hepatocellular carcinoma cells (HepG2) cultured in minimal and rich media (with nonessential amino acids and GSH). The cells were cultured at 1% hypoxia, 10% tissue normoxia, and 21% atmospheric normoxia. The total cell count was determined by trypan blue exclusion dye and the expression on mRNA level by RT-PCR. The result indicated that the expression of glutathione-dependent enzymes (GSTA, M, P, and GPX2) was sensitive to oxygen and medium type. At 1% hypoxia the enzyme expression (with the exception of GSTA) was higher in minimal compared to rich medium, whereas at 10% normoxia it was higher in the rich medium. The expression was oxygen-dependent in both types of medium. Among phenol sulfotransferase SULT1A1 was not sensitive to studied factors, whereas the expression of SULT1A3 was depended on oxygen only in minimal medium. It can be concluded that in HepG2 cells, the detoxification by conjugation with glutathione and, to a lower extent with sulfate, may be affected by hypoxia and/or limited nutrients' availability. Besides, because the data obtained at 10% oxygen significantly differ from those at 21%, the comparative studies on hypoxia should be performed in relation to 10% but not 21% oxygen. PMID:26599691

  5. A quantum-well superlattice solar cell for enhanced current output and minimized drop in open-circuit voltage under sunlight concentration

    International Nuclear Information System (INIS)

    Insertion of quantum wells (QWs) extends the absorption edge to a longer wavelength than the value of a p-i-n cell without the QWs, which is preferable for the improved current matching of a InGaP/GaAs/Ge multijunction cell. The QWs, however, reduce the open-circuit voltage (Voc) and degrade the fill factor; the latter is significant for a large number of QWs that are mandatory for sufficient light absorption. As a structure to minimize these drawbacks, a QW superlattice, a strain-balanced In0.13Ga0.86As (4.7 nm)/GaAs0.57P0.43 (3.1 nm) stack, was implemented by metalorganic vapour-phase epitaxy. It brought about an enhancement in short-circuit current density (3.0 mA cm-2) with a minimal drop in Voc(0.03 V) compared with a p-i-n cell without the superlattice. The collection efficiency of photocarriers from the wells to an external circuit was evaluated: the efficiency was above 0.95 for the superlattice, while it was below 0.8 at a large forward bias for a conventional QW cell with thicker barriers. With the fast electron-hole separation in the superlattice owing to tunnelling transport, the superlattice cell exhibited a steeper increase in Voc as a function of the sunlight concentration ratio than the conventional QW cell: at the concentration ratio of 50, the value of Voc for the superlattice cell was almost equivalent to the value of the GaAs p-i-n cell without QWs. As a possible mechanism behind such an enhancement in Voc, photocurrent generation by two-step photon absorption was observed, using the electron ground state of the superlattice as an intermediate state.

  6. Cost-effective differentiation of hepatocyte-like cells from human pluripotent stem cells using small molecules.

    Science.gov (United States)

    Tasnim, Farah; Phan, Derek; Toh, Yi-Chin; Yu, Hanry

    2015-11-01

    Significant efforts have been invested into the differentiation of stem cells into functional hepatocyte-like cells that can be used for cell therapy, disease modeling and drug screening. Most of these efforts have been concentrated on the use of growth factors to recapitulate developmental signals under in vitro conditions. Using small molecules instead of growth factors would provide an attractive alternative since small molecules are cell-permeable and cheaper than growth factors. We have developed a protocol for the differentiation of human embryonic stem cells into hepatocyte-like cells using a predominantly small molecule-based approach (SM-Hep). This 3 step differentiation strategy involves the use of optimized concentrations of LY294002 and bromo-indirubin-3'-oxime (BIO) for the generation of definitive endoderm; sodium butyrate and dimethyl sulfoxide (DMSO) for the generation of hepatoblasts and SB431542 for differentiation into hepatocyte-like cells. Activin A is the only growth factor required in this protocol. Our results showed that SM-Hep were morphologically and functionally similar or better compared to the hepatocytes derived from the growth-factor induced differentiation (GF-Hep) in terms of expression of hepatic markers, urea and albumin production and cytochrome P450 (CYP1A2 and CYP3A4) activities. Cell viability assays following treatment with paradigm hepatotoxicants Acetaminophen, Chlorpromazine, Diclofenac, Digoxin, Quinidine and Troglitazone showed that their sensitivity to these drugs was similar to human primary hepatocytes (PHHs). Using SM-Hep would result in 67% and 81% cost reduction compared to GF-Hep and PHHs respectively. Therefore, SM-Hep can serve as a robust and cost effective replacement for PHHs for drug screening and development. PMID:26310107

  7. Costly Cell Phones: The Impact of Cell Phone Rings on Academic Performance

    Science.gov (United States)

    End, Christian M.; Worthman, Shaye; Mathews, Mary Bridget; Wetterau, Katharina

    2010-01-01

    College students participated in a study on the "psychology of note taking" during which they took notes on video content and later completed a multiple-choice test on the material. Researchers assigned 71 participants to either the ringing condition (the video was disrupted by a ringing cell phone) or the control condition (no cell phone rings…

  8. Pancratistatin induces apoptosis in clinical leukemia samples with minimal effect on non-cancerous peripheral blood mononuclear cells

    OpenAIRE

    McNulty James; Hamm Caroline; Griffin Carly; Pandey Siyaram

    2010-01-01

    Abstract Background Pancratistatin, a natural compound extracted from Hymenocallis littoralis, can selectively induce apoptosis in several cancer cell lines. In this ex vivo study, we evaluated the effect of pancratistatin on peripheral blood mononuclear cells obtained from 15 leukemia patients prior to clinical intervention of newly diagnosed patients, as well as others of different ages in relapse and at various disease progression states. Results Mononuclear cells from healthy volunteers a...

  9. Mesenchymal stem cell transplantation for the infarcted heart: a role in minimizing abnormalities in cardiac-specific energy metabolism

    OpenAIRE

    Hughey, Curtis C.; Johnsen, Virginia L.; Ma, Lianli; James, Freyja D.; Young, Pampee P.; Wasserman, David H.; Rottman, Jeffrey N.; Hittel, Dustin S.; Shearer, Jane

    2011-01-01

    Intense interest has been focused on cell-based therapy for the infarcted heart given that stem cells have exhibited the ability to reduce infarct size and mitigate cardiac dysfunction. Despite this, it is unknown whether mesenchymal stem cell (MSC) therapy can prevent metabolic remodeling following a myocardial infarction (MI). This study examines the ability of MSCs to rescue the infarcted heart from perturbed substrate uptake in vivo. C57BL/6 mice underwent chronic ligation of the left ant...

  10. Does primary neoadjuvant systemic therapy eradicate minimal residual disease? Analysis of disseminated and circulating tumor cells before and after therapy

    OpenAIRE

    Kasimir-Bauer, Sabine; BITTNER, ANN-KATHRIN; König, Lisa; Reiter, Katharina; Keller, Thomas; Kimmig, Rainer; HOFFMANN, OLIVER

    2016-01-01

    Background Patients with breast cancer (BC) undergoing neoadjuvant chemotherapy (NACT) may experience metastatic relapse despite achieving a pathologic complete response. We analyzed patients with BC before and after NACT for disseminated tumor cells (DTCs) in the bone marrow(BM); comprehensively characterized circulating tumor cells (CTCs), including stem cell–like CTCs (slCTCs), in blood to prove the effectiveness of treatment on these cells; and correlated these findings with response to t...

  11. Cost effectiveness of cord blood versus bone marrow and peripheral blood stem cells

    Directory of Open Access Journals (Sweden)

    Thomas Bart

    2010-10-01

    Full Text Available Thomas BartSwiss Blood Stem Cells, Bern, SwitzerlandAbstract: Umbilical cord blood (CB has become, since its first successful use more than two decades ago, an increasingly important source of blood stem cells. In this light, an overview of current usage of CB in the field of unrelated hematopoietic blood stem cell transplantation (HSCT is given. The three main sources of hematopoietic stem cells: bone marrow (BM, peripheral blood stem cells (PBSC, and cord blood (CB are compared as regards their current quantitative usage in HSCT. A cost analysis of the named three hematopoietic blood stem cell (HSC sources, taking into account various factors, is undertaken. The health economical comparison shows significant differences between CB on the one side, and BM and PBSC on the other. The consequences for the public health side and propositions for a possible health care policy, especially regarding future resource allocation towards the different choices for HSCT products, are discussed. An outlook on the possible future usage of BM, PBSC, and CB and its implications on health systems, donor registries, and CB banks is given.Keywords: health economy, cord blood, hematopoietic stem cell transplantation

  12. Waste minimization handbook, Volume 1

    International Nuclear Information System (INIS)

    This technical guide presents various methods used by industry to minimize low-level radioactive waste (LLW) generated during decommissioning and decontamination (D and D) activities. Such activities generate significant amounts of LLW during their operations. Waste minimization refers to any measure, procedure, or technique that reduces the amount of waste generated during a specific operation or project. Preventive waste minimization techniques implemented when a project is initiated can significantly reduce waste. Techniques implemented during decontamination activities reduce the cost of decommissioning. The application of waste minimization techniques is not limited to D and D activities; it is also useful during any phase of a facility's life cycle. This compendium will be supplemented with a second volume of abstracts of hundreds of papers related to minimizing low-level nuclear waste. This second volume is expected to be released in late 1996

  13. Waste minimization handbook, Volume 1

    Energy Technology Data Exchange (ETDEWEB)

    Boing, L.E.; Coffey, M.J.

    1995-12-01

    This technical guide presents various methods used by industry to minimize low-level radioactive waste (LLW) generated during decommissioning and decontamination (D and D) activities. Such activities generate significant amounts of LLW during their operations. Waste minimization refers to any measure, procedure, or technique that reduces the amount of waste generated during a specific operation or project. Preventive waste minimization techniques implemented when a project is initiated can significantly reduce waste. Techniques implemented during decontamination activities reduce the cost of decommissioning. The application of waste minimization techniques is not limited to D and D activities; it is also useful during any phase of a facility`s life cycle. This compendium will be supplemented with a second volume of abstracts of hundreds of papers related to minimizing low-level nuclear waste. This second volume is expected to be released in late 1996.

  14. Inducible nitric-oxide synthase plays a minimal role in lymphocytic choriomeningitis virus-induced, T cell-mediated protective immunity and immunopathology

    DEFF Research Database (Denmark)

    Bartholdy, C; Nansen, A; Christensen, Jeanette Erbo; Marker, O; Thomsen, Allan Randrup

    . This might suggest a role of NO in regulating vascular reactivity in the context of T cell-mediated inflammation. In conclusion, these findings indicate a minimal role for iNOS/NO in the host response to LCMV. Except for a reduced local oedema in the knockout mice, iNOS/NO seems to be redundant in......By using mice with a targetted disruption in the gene encoding inducible nitric-oxide synthase (iNOS), we have studied the role of nitric oxide (NO) in lymphocytic choriomeningitis virus (LCMV)-induced, T cell-mediated protective immunity and immunopathology. The afferent phase of the T cell...... the up-regulation of proinflammatory cytokine/chemokine genes significantly, nor did it influence the development of fatal meningitis. However, a reduced virus-specific delayed-type hypersensitivity reaction was observed in iNOS-deficient mice compared with both IFN-gamma-deficient and wild-type mice...

  15. Planetary protection: Elements for cost minimization

    Science.gov (United States)

    Debus, Andre

    2006-10-01

    In line with the UN Outer Space Treaty (article IX of the Outer Space Treaty—London/Washington January 27, 1967) [United Nations Treaty on Principles Governing the Activities of States in the Exploration and Use of Outer Space, including the Moon and Other Celestial Bodies (the “Outer Space Treaty”) referenced 610 UNTS 205—resolution 2222(XXI) of December 1966 [1

  16. Low-cost zinc-plated photoanode for fabric-type dye-sensitized solar cells

    Science.gov (United States)

    Kong, Lingfeng; Bao, Yunna; Guo, Wanwan; Cheng, Li; Du, Jun; Liu, Renlong; Wang, Yundong; Fan, Xing; Tao, Changyuan

    2016-02-01

    Fabric-type flexible solar cells have been recently proposed as a very promising power source for wearable electronics. To increase the photocurrent of fabric-type flexible solar cells, low-cost zinc-plated wire and mesh photoanodes are assembled for the first time through a mild wet process. Given the protection of the compact protection layer, the DSSC device could benefit from the low work function of Zn and self-repairing behavior on the Zn/ZnO interface. An evident current increase by ∼6 mA/cm2 could be observed after coating a layer of metal Zn on various metal substrates, such as traditional stainless steel wire. Given the self-repairing behavior on Zn/ZnO interface, the Zn layer can help to improve the interfacial carrier transfer, leading to better photovoltaic performance, for both liquid-type and solid-type cells.

  17. High cell-density processes in batch mode of a genetically engineered Escherichia coli strain with minimized overflow metabolism using a pressurized bioreactor.

    Science.gov (United States)

    Knabben, Ingo; Regestein, Lars; Marquering, Frank; Steinbusch, Sven; Lara, Alvaro R; Büchs, Jochen

    2010-10-01

    A common method to minimize overflow metabolism and to enable high cell-density is to operate microbial processes in fed-batch mode under carbon-limiting conditions. This requires sophisticated process control schemes with expensive hardware equipment and software and well-characterized processes parameters. To generate high-cell density, a more simplified strategy would be beneficial. Therefore, a genetically engineered Escherichia coli strain with a modified glucose uptake system was cultivated in batch mode. In the applied strain, the usual phosphotransferase system of a K12-derived strain was inactivated, while the galactose permease system was amplified. Upon cultivating this E. coli strain in pure minimal media, the acetate concentration did not exceed values of 0.35 g L(-1), even when the batch fermentation was started with a glucose concentration of 130 g L(-1). Finally, maximum biomass concentrations of 48 g L(-1) dry cell weight and maximum space-time yields of 2.10 g L(-1) h(-1) were reached. To provide an unlimited growth under fully aerobic conditions (DOT>30%) at comparatively low values for specific power input (3-4 kW m(-3)), a pressurized bioreactor was used. Consequentially, to our knowledge, this study using a bioreactor with elevated headspace pressure generate the highest oxygen transfer rate (451 mmol L(-1) h(-1)) ever reached in batch cultivations. PMID:20630485

  18. DEVELOPMENT OF LOW-COST MANUFACTURING PROCESSES FOR PLANAR, MULTILAYER SOLID OXIDE FUEL CELL ELEMENTS

    Energy Technology Data Exchange (ETDEWEB)

    Scott Swartz; Matthew Seabaugh; William Dawson; Harlan Anderson; Tim Armstrong; Michael Cobb; Kirby Meacham; James Stephan; Russell Bennett; Bob Remick; Chuck Sishtla; Scott Barnett; John Lannutti

    2004-06-12

    This report summarizes the results of a four-year project, entitled, ''Low-Cost Manufacturing Of Multilayer Ceramic Fuel Cells'', jointly funded by the U.S. Department of Energy, the State of Ohio, and by project participants. The project was led by NexTech Materials, Ltd., with subcontracting support provided by University of Missouri-Rolla, Michael A. Cobb & Co., Advanced Materials Technologies, Inc., Edison Materials Technology Center, Gas Technology Institute, Northwestern University, and The Ohio State University. Oak Ridge National Laboratory, though not formally a subcontractor on the program, supported the effort with separate DOE funding. The objective of the program was to develop advanced manufacturing technologies for making solid oxide fuel cell components that are more economical and reliable for a variety of applications. The program was carried out in three phases. In the Phase I effort, several manufacturing approaches were considered and subjected to detailed assessments of manufacturability and development risk. Estimated manufacturing costs for 5-kW stacks were in the range of $139/kW to $179/kW. The risk assessment identified a number of technical issues that would need to be considered during development. Phase II development work focused on development of planar solid oxide fuel cell elements, using a number of ceramic manufacturing methods, including tape casting, colloidal-spray deposition, screen printing, spin-coating, and sintering. Several processes were successfully established for fabrication of anode-supported, thin-film electrolyte cells, with performance levels at or near the state-of-the-art. The work in Phase III involved scale-up of cell manufacturing methods, development of non-destructive evaluation methods, and comprehensive electrical and electrochemical testing of solid oxide fuel cell materials and components.

  19. A cost-benefit model comparing the California Milk Cell Test and Milk Electrical Resistance Test

    Directory of Open Access Journals (Sweden)

    Inge-Marie Petzer

    2013-03-01

    Full Text Available The indirect effects of mastitis treatment are often overlooked in cost-benefit analyses, but it may be beneficial for the dairy industry to consider them. The cost of mastitis treatment may increase when the duration of intra-mammary infections are prolonged due to misdiagnosis of host-adapted mastitis. Laboratory diagnosis of mastitis can be costly and time consuming, therefore cow-side tests such as the California Milk Cell Test (CMCT and Milk Electrical Resistance (MER need to be utilised to their full potential. The aim of this study was to determine the relative benefit of using these two tests separately and in parallel. This was done using a partial-budget analysis and a cost-benefit model to estimate the benefits and costs of each respective test and the parallel combination thereof. Quarter milk samples (n= 1860 were taken from eight different dairy herds in South Africa. Milk samples were evaluated by means of the CMCT, hand-held MER meter and cyto-microbiological laboratory analysis. After determining the most appropriate cut-off points for the two cow-side tests, the sensitivity and specificity of the CMCT (Se= 1.00, Sp= 0.66, MER (Se= 0.92, Sp= 0.62 and the tests done in parallel (Se= 1.00, Sp= 0.87 were calculated. The input data that were used for partial-budget analysis and in the cost-benefit model were based on South African figures at the time of the study, and on literature. The total estimated financial benefit of correct diagnosis of host-adapted mastitis per cow for the CMCT, MER and the tests done in parallel was R898.73, R518.70 and R1064.67 respectively. This involved taking the expected benefit of a correct test result per cow, the expected cost of an error per cow and the cost of the test into account. The CMCT was shown to be 11%more beneficial than the MER test, whilst using the tests in parallel was shown to be the most beneficial method for evaluating the mastitis-control programme. Therefore

  20. A cost-effective system for differentiation of intestinal epithelium from human induced pluripotent stem cells.

    Science.gov (United States)

    Ogaki, Soichiro; Morooka, Mayu; Otera, Kaito; Kume, Shoen

    2015-01-01

    The human intestinal epithelium is a useful model for pharmacological studies of absorption, metabolism, drug interactions, and toxicology, as well as for studies of developmental biology. We established a rapid and cost effective system for differentiation of human induced pluripotent stem (iPS) cells into definitive endoderm (DE) cells. In the presence of dimethyl sulfoxide (DMSO), a low concentration of Activin at 6.25 ng/ml is sufficient to give a similar differentiation efficiency with that using Activin at 100 ng/ml at the presence of Wnt activator. In the presence of DMSO, Activin at low concentration triggered hiPS cells to undergo differentiation through G1 arrest, reduce apoptosis, and potentiate activation of downstream targets, such as SMAD2 phosphorylation and SOX17 expression. This increased differentiation into CDX2 + SOX17 + DE cells. The present differentiation procedure therefore permits rapid and efficient derivation of DE cells, capable of differentiating into intestinal epithelium upon BIO and DAPT treatment and of giving rise to functional cells, such as enterocytes. PMID:26616277

  1. Cost-effective platinum alloy counter electrodes for liquid-junction dye-sensitized solar cells

    Science.gov (United States)

    Li, Yanjuan; Tang, Qunwei; Yu, Liangmin; Yan, Xuefeng; Dong, Lei

    2016-02-01

    One of the challenges in developing advanced dye-sensitized solar cells (DSSCs) is the pursuit of cost-effective and robust counter electrodes (CEs). We present here the successful synthesis of binary PtxM100-x (M = Ni, Co, Fe) alloy nanostructures on Ti foil by a facile and environmental-friendly strategy for utilization as CEs in liquid-junction DSSCs. Due to the reasonable charge-transfer ability and excellent electrocatalytic activity, the resultant DSSC yields a promising power conversion efficiency (PCE) of 6.42% with binary Pt0.28Ni99.72 CE in comparison with 6.18% for pristine Pt CE based device. The easy synthesis, cost-effectiveness, and good electrocatalytic property may help the Pt0.28Ni99.72 nanostructure stand out as an alternative CE electrocatalyst in a DSSC.

  2. Fractal heterogeneity in minimal matrix models of scars modulates stiff-niche stem-cell responses via nuclear exit of a mechanorepressor

    Science.gov (United States)

    Dingal, P. C. Dave P.; Bradshaw, Andrew M.; Cho, Sangkyun; Raab, Matthew; Buxboim, Amnon; Swift, Joe; Discher, Dennis E.

    2015-09-01

    Scarring is a long-lasting problem in higher animals, and reductionist approaches could aid in developing treatments. Here, we show that copolymerization of collagen I with polyacrylamide produces minimal matrix models of scars (MMMS), in which fractal-fibre bundles segregate heterogeneously to the hydrogel subsurface. Matrix stiffens locally--as in scars--while allowing separate control over adhesive-ligand density. The MMMS elicits scar-like phenotypes from mesenchymal stem cells (MSCs): cells spread and polarize quickly, increasing nucleoskeletal lamin-A yet expressing the `scar marker' smooth muscle actin (SMA) more slowly. Surprisingly, expression responses to MMMS exhibit less cell-to-cell noise than homogeneously stiff gels. Such differences from bulk-average responses arise because a strong SMA repressor, NKX2.5, slowly exits the nucleus on rigid matrices. NKX2.5 overexpression overrides rigid phenotypes, inhibiting SMA and cell spreading, whereas cytoplasm-localized NKX2.5 mutants degrade in well-spread cells. MSCs thus form a `mechanical memory' of rigidity by progressively suppressing NKX2.5, thereby elevating SMA in a scar-like state.

  3. Effectiveness and cost-effectiveness of a minimal psychological intervention to reduce non-severe depression in chronically ill elderly patients: the design of a randomised controlled trial [ISRCTN92331982

    Directory of Open Access Journals (Sweden)

    Diederiks JPM

    2006-06-01

    Full Text Available Abstract Background Depression is a prevalent disorder in chronically ill elderly persons. It may decrease quality of life, and increase functional disability, medical costs, and healthcare utilisation. Because patients may slip into a downward spiral, early recognition and treatment of depression is important. Depression can be treated with antidepressants or psychological interventions; the latter can also be applied by trained paraprofessionals. In this paper, we describe the design of the DELTA study (Depression in Elderly with Long-Term Afflictions. The first objective of the DELTA study is to evaluate the effectiveness and cost-effectiveness of a minimal psychological intervention (MPI to reduce depression in chronically ill elderly patients. The second objective is to evaluate whether a potential effect of the MPI may differ between types of chronic illnesses. The tailor-made intervention is administered by nurses, who are trained in the principles of cognitive behavioural therapy and self-management. Methods/Design DELTA is a two-armed randomised controlled trial, comparing MPI to usual care. A total number of 180 patients with diabetes mellitus type II (DM and 180 patients with chronic obstructive pulmonary disease (COPD, who in addition suffer from non-severe depression, will be included in the study. In our study, non-severe depression is defined as having minor depression, mild major depression or moderate major depression. The primary outcome measure is depression using the Beck Depression Inventory. Secondary outcome measures include quality of life, daily functioning, self-efficacy, autonomy, and participation. In the economic evaluation, cost-effectiveness and cost-utility ratios will be calculated. Furthermore, a process evaluation will be carried out. Analyses will include both univariate and multivariate techniques and according to the intention to treat principle. The economic evaluation will be done from a societal

  4. Development of micromorph tandem solar cells on flexible low-cost plastic substrates

    Energy Technology Data Exchange (ETDEWEB)

    Haug, F.-J.; Soederstroem, T.; Python, M.; Terrazzoni-Daudrix, V.; Niquille, X.; Ballif, C. [Institute of Microtechnology, University of Neuchatel, Rue A.-L. Breguet 2, CH 2000 Neuchatel (Switzerland)

    2009-06-15

    We report on the development of fully flexible microcrystalline and micromorph tandem solar cells directly on low-cost substrates like poly-ethylen-terephtalate (PET) and poly-ethylen-naphtalate (PEN). The cells are deposited in nip or nip/nip configuration on the plastic substrate coated with a highly reflecting Ag-ZnO back contact. Light trapping is achieved by combining a periodically textured substrate and a diffusing ZnO front contact. Single-junction microcrystalline cells with a stable efficiency of 8.7% are achieved with an i-layer thickness of 1.2 {mu}m. In tandem devices we obtain an efficiency of 10.9% (initial) with an open circuit voltage of 1.35 V and a fill factor (FF) of 71.5%. These cells are slightly top limited with 11.26 and 11.46 mA/cm{sup 2} in the amorphous (270 nm thick) and the microcrystalline (1.2 {mu}m thick) sub-cells, respectively. We introduce an intermediate reflector (IR) between the bottom and the top cell because it allows increasing the top cell current without compromising the stability by a thicker absorber. The IRs consist of either an ex-situ ZnO or a low refractive index P-doped silicon-oxygen compound deposited in-situ with a plasma process that is fully compatible with solar cell processing. We demonstrate significant current improvement (up to 8% relative) using both kinds of IRs. (author)

  5. Low cost fuel cell diffusion layer configured for optimized anode water management

    Science.gov (United States)

    Owejan, Jon P; Nicotera, Paul D; Mench, Matthew M; Evans, Robert E

    2013-08-27

    A fuel cell comprises a cathode gas diffusion layer, a cathode catalyst layer, an anode gas diffusion layer, an anode catalyst layer and an electrolyte. The diffusion resistance of the anode gas diffusion layer when operated with anode fuel is higher than the diffusion resistance of the cathode gas diffusion layer. The anode gas diffusion layer may comprise filler particles having in-plane platelet geometries and be made of lower cost materials and manufacturing processes than currently available commercial carbon fiber substrates. The diffusion resistance difference between the anode gas diffusion layer and the cathode gas diffusion layer may allow for passive water balance control.

  6. Adjustment of Cell-Type Composition Minimizes Systematic Bias in Blood DNA Methylation Profiles Derived by DNA Collection Protocols.

    Directory of Open Access Journals (Sweden)

    Yuh Shiwa

    Full Text Available Differences in DNA collection protocols may be a potential confounder in epigenome-wide association studies (EWAS using a large number of blood specimens from multiple biobanks and/or cohorts. Here we show that pre-analytical procedures involved in DNA collection can induce systematic bias in the DNA methylation profiles of blood cells that can be adjusted by cell-type composition variables. In Experiment 1, whole blood from 16 volunteers was collected to examine the effect of a 24 h storage period at 4°C on DNA methylation profiles as measured using the Infinium HumanMethylation450 BeadChip array. Our statistical analysis showed that the P-value distribution of more than 450,000 CpG sites was similar to the theoretical distribution (in quantile-quantile plot, λ = 1.03 when comparing two control replicates, which was remarkably deviated from the theoretical distribution (λ = 1.50 when comparing control and storage conditions. We then considered cell-type composition as a possible cause of the observed bias in DNA methylation profiles and found that the bias associated with the cold storage condition was largely decreased (λ adjusted = 1.14 by taking into account a cell-type composition variable. As such, we compared four respective sample collection protocols used in large-scale Japanese biobanks or cohorts as well as two control replicates. Systematic biases in DNA methylation profiles were observed between control and three of four protocols without adjustment of cell-type composition (λ = 1.12-1.45 and no remarkable biases were seen after adjusting for cell-type composition in all four protocols (λ adjusted = 1.00-1.17. These results revealed important implications for comparing DNA methylation profiles between blood specimens from different sources and may lead to discovery of disease-associated DNA methylation markers and the development of DNA methylation profile-based predictive risk models.

  7. Fully crystalline perovskite-perylene hybrid photovoltaic cell capable of 1.2 V output with a minimized voltage loss

    OpenAIRE

    Ayumi Ishii; Ajay Kumar Jena; Tsutomu Miyasaka

    2014-01-01

    A fully crystalline heterojunction of organo-metal-halide perovskite, CH3NH3PbI3−xClx (X < 0.24), and perylene constitutes a planar photovoltaic cell that yields a photovoltage exceeding 1.2 V with a single junction cell absorbing up to 800 nm. Here, perylene not only works as a hole conductor but also contributes to photovoltage as a photoconductor. The crystalline plane orientation of perovskite prepared on TiO2 was controlled by thermal annealing such that the lead halide (110) plane that ...

  8. Defect Engineering, Cell Processing, and Modeling for High-Performance, Low-Cost Crystalline Silicon Photovoltaics

    Energy Technology Data Exchange (ETDEWEB)

    Buonassisi, Tonio

    2013-02-26

    The objective of this project is to close the efficiency gap between industrial multicrystalline silicon (mc-Si) and monocrystalline silicon solar cells, while preserving the economic advantage of low-cost, high-volume substrates inherent to mc-Si. Over the course of this project, we made significant progress toward this goal, as evidenced by the evolution in solar-cell efficiencies. While most of the benefits of university projects are diffuse in nature, several unique contributions can be traced to this project, including the development of novel characterization methods, defect-simulation tools, and novel solar-cell processing approaches mitigate the effects of iron impurities ("Impurities to Efficiency" simulator) and dislocations. In collaboration with our industrial partners, this project contributed to the development of cell processing recipes, specialty materials, and equipment that increased cell efficiencies overall (not just multicrystalline silicon). Additionally, several students and postdocs who were either partially or fully engaged in this project (as evidenced by the publication record) are currently in the PV industry, with others to follow.

  9. End of induction minimal residual disease alone is not a useful determinant for risk stratified therapy in pediatric T-cell acute lymphoblastic leukemia.

    Science.gov (United States)

    Parekh, Chintan; Gaynon, Paul S; Abdel-Azim, Hisham

    2015-11-01

    The role of end of induction minimal residual disease (MRD) as determined by flow cytometry for treatment assignment in pediatric T-cell acute lymphoblastic leukemia (T-ALL) is not well defined. We studied 33 children with newly diagnosed T-ALL. Thirty-two of 33 patients remain in continuous complete remission at a median of 4 years. Nineteen patients were MRD positive at the end of induction and all remain in remission with augmented Berlin Frankfurt Münster-based therapy. One patient underwent hematopoietic stem cell transplant for rising MRD. Persistent end of induction MRD alone is not an indication to alter therapy in pediatric T-ALL. PMID:25976383

  10. Optical Metrology for CIGS Solar Cell Manufacturing and its Cost Implications

    Science.gov (United States)

    Sunkoju, Sravan Kumar

    Solar energy is a promising source of renewable energy which can meet the demand for clean energy in near future with advances in research in the field of photovoltaics and cost reduction by commercialization. Availability of a non-contact, in-line, real time robust process control strategies can greatly aid in reducing the gap between cell and module efficiencies, thereby leading to cost-effective large-scale manufacturing of high efficiency CIGS solar cells. In order to achieve proper process monitoring and control for the deposition of the functional layers of CuIn1-xGaxSe 2 (CIGS) based thin film solar cell, optical techniques such as spectroscopic reflectometry and polarimetry are advantageous because they can be set up in an unobtrusive manner in the manufacturing line, and collect data in-line and in-situ. The use of these techniques requires accurate optical models that correctly represent the properties of the layers being deposited. In this study, Spectroscopic ellipsometry (SE) has been applied for the characterization of each individual stage of CIGS layers deposited using the 3-stage co-evaporation process along with the other functional layers. Dielectric functions have been determined for the energy range from 0.7 eV to 5.1 eV. Critical-point line-shape analysis was used in this study to determine the critical point energies of the CIGS based layers. To control the compositional and thickness uniformity of all the functional layers during the fabrication of CIGS solar cells over large areas, multilayer photovoltaics (PV) stack optical models were developed with the help of extracted dielectric functions. In this study, mapping capability of RC2 spectroscopic ellipsometer was used to map all the functional layer thicknesses of a CIGS solar cell in order to probe the spatial non-uniformities that can affect the performance of a cell. The optical functions for each of the stages of CIGS 3-stage deposition process along with buffer layer and transparent

  11. Osteosarcoma tissues and cell lines from patients with differing serum alkaline phosphatase concentrations display minimal differences in gene expression patterns.

    Science.gov (United States)

    Rodrigues, L C de Sá; Holmes, K E; Thompson, V; Piskun, C M; Lana, S E; Newton, M A; Stein, T J

    2016-06-01

    Serum alkaline phosphatase (ALP) concentration is a prognostic factor for osteosarcoma in multiple studies, although its biological significance remains incompletely understood. To determine whether gene expression patterns differed in osteosarcoma from patients with differing serum ALP concentrations, microarray analysis was performed on 18 primary osteosarcoma samples and six osteosarcoma cell lines from dogs with normal and increased serum ALP concentration. No differences in gene expression patterns were noted between tumours or cell lines with differing serum ALP concentration using a gene-specific two-sample t-test. Using a more sensitive empirical Bayes procedure, defective in cullin neddylation 1 domain containing 1 (DCUN1D1) was increased in both the tissue and cell lines of the normal ALP group. Using quantitative PCR (qPCR), differences in DCUN1D1 expression between the two groups failed to reach significance. The homogeneity of gene expression patterns of osteosarcoma associated differing serum ALP concentrations are consistent with previous studies suggesting serum ALP concentration is not associated with intrinsic differences of osteosarcoma cells. PMID:25643733

  12. Novel cost-effective bifacial silicon solar cells with 19.4% front and 18.1% rear efficiency

    Science.gov (United States)

    Hübner, Andreas; Aberle, Armin G.; Hezel, Rudolf

    1997-02-01

    Bifacial solar cells are a promising possibility to lower the costs of solar electricity compared to conventional monofacial solar cells. These devices utilize the sunlight more efficiently since they are able to convert light incident on both sides of the cell. In this letter, a novel, cost-effective bifacial silicon solar cell structure is presented. On float-zone silicon, the cells exhibit conversion efficiencies of 19.4% and 16.5% under 1-sun front and rear illumination, respectively. Furthermore, a "symmetrical" version of the cells is presented demonstrating front and rear efficiencies of 18.4% and 18.1%. In spite of the simplicity of the cell fabrication process, these are the highest independently confirmed efficiencies ever reported for bifacial silicon solar cells.

  13. Intermittent use of a low-cost alkaline fuel cell-hybrid system for electric vehicles

    Science.gov (United States)

    Kordesch, Karl; Gsellmann, Josef; Cifrain, Martin; Voss, Susanne; Hacker, Victor; Aronson, Robert R.; Fabjan, Christoph; Hejze, Thomas; Daniel-Ivad, Josef

    Alkaline fuel cell (AFC) hybrids with the capability to shut down completely between uses (by draining the circulating KOH electrolyte) can expect an operating life of about 4000 h, which is equivalent to 200,000 km of driving, They should be able to compete on cost with heat engines (US50 to US100 per kW). An early model is the hydrogen/air fuel cell lead-acid hybrid car, built by K. Kordesch in the 1970s. Improved air electrodes plus new variations of the bipolar stack assembly developed in Graz, make success probable. In cooperation with Electric Auto (EAC), an ammonia cracker is also in development. A RAM™ battery-AFC hybrid combination has been optimized.

  14. Low Cost Amorphous Silicon Intrinsic Layer for Thin-Film Tandem Solar Cells

    Directory of Open Access Journals (Sweden)

    Ching-In Wu

    2013-01-01

    Full Text Available The authors propose a methodology to improve both the deposition rate and SiH4 consumption during the deposition of the amorphous silicon intrinsic layer of the a-Si/μc-Si tandem solar cells prepared on Gen 5 glass substrate. It was found that the most important issue is to find out the saturation point of deposition rate which guarantees saturated utilization of the sourcing gas. It was also found that amorphous silicon intrinsic layers with the same k value will result in the same degradation of the fabricated modules. Furthermore, it was found that we could significantly reduce the production cost of the a-Si/μc-Si tandem solar cells prepared on Gen 5 glass substrate by fine-tuning the process parameters.

  15. Contributions of phosphorylation to regulation of OCTN2 uptake of carnitine are minimal in BeWo cells.

    Science.gov (United States)

    Rytting, Erik; Audus, Kenneth L

    2008-02-01

    Physiological functions of organic cation transporters (OCTs) in the placenta include transporting essential nutrients from the maternal to fetal circulations. OCTN2 transports carnitine with high affinity, and the transport of several drugs has also been shown to be mediated by this transporter. In this work, the role of phosphorylation and dephosphorylation mechanisms in regulating OCTN2 was investigated by observing the effects of various activators and inhibitors of kinases and phosphatases on the uptake of carnitine in BeWo cells, a human choriocarcinoma trophoblast cell line frequently used as an in vitro model of the rate-limiting barrier for maternal-fetal exchange. Preincubation with genistein resulted in significant increases in both alkaline phosphatase (ALP) activity and carnitine uptake. Levamisole, an ALP inhibitor, caused a more substantial decrease in carnitine uptake than expected from its corresponding decrease in ALP activity. It was determined that levamisole competitively inhibits carnitine uptake, with a K(i) value of 1.01+/-0.05mM, and this effect has a greater role in decreasing carnitine uptake than any indirect effects of ALP inhibition upon OCTN2 function. Progesterone also competitively inhibited carnitine uptake (K(i)=48.6+/-5.0muM), but had no effect on ALP activity in BeWo cells. PMID:17977516

  16. Stem cell Transplantation for Eradication of Minimal PAncreatic Cancer persisting after surgical Excision (STEM PACE Trial, ISRCTN47877138): study protocol for a phase II study

    International Nuclear Information System (INIS)

    Pancreatic cancer is the third most common cancer related cause of death. Even in the 15% of patients who are eligible for surgical resection the outlook is dismal with less than 10% of patients surviving after 5 years. Allogeneic hematopoietic (allo-HSCT) stem cell transplantation is an established treatment capable of to providing cure in a variety of hematopoietic malignancies. Best results are achieved when the underlying neoplasm has been turned into a stage of minimal disease by chemotherapy. Allo-HSCT in advanced solid tumors including pancreatic cancer have been of limited success, however studies of allo-HSCT in solid tumors in minimal disease situations have never been performed. The aim of this trial is to provide evidence for the clinical value of allo-HSCT in pancreatic cancer put into a minimal disease status by effective surgical resection and standard adjuvant chemotherapy. The STEM PACE trial is a single center, phase II study to evaluate adjuvant allogeneic hematopoietic stem cell transplantation in pancreatic cancer after surgical resection. The study will evaluate as primary endpoint 2 year progression free survival and will generate first time state-of-the-art scientific clinical evidence if allo-HSCT is feasible and if it can provide long term disease control in patients with effectively resected pancreatic cancer. Screened eligible patients after surgical resection and standard adjuvant chemotherapy with HLA matched related stem cell donor can participate. Patients without a matched donor will be used as a historical control. Study patients will undergo standard conditioning for allo-HSCT followed by transplantation of allogeneic unmanipulated peripheral blood stem cells. The follow up of the patients will continue for 2 years. Secondary endpoints will be evaluated on 7 postintervention visits. The principal question addressed in this trial is whether allo-HSCT can change the unfavourable natural course of this disease. The underlying

  17. Performance and cost of automotive fuel cell systems with ultra-low platinum loadings

    Science.gov (United States)

    Ahluwalia, R. K.; Wang, X.; Kwon, J.; Rousseau, A.; Kalinoski, J.; James, B.; Marcinkoski, J.

    2011-05-01

    An automotive polymer-electrolyte fuel cell (PEFC) system with ultra-low platinum loading (0.15 mg-Pt cm-2) has been analyzed to determine the relationship between its design-point efficiency and the system efficiency at part loads, efficiency over drive cycles, stack and system costs, and heat rejection. The membrane electrode assemblies in the reference PEFC stack use nanostructured, thin-film ternary catalysts supported on organic whiskers and a modified perfluorosulfonic acid membrane. The analyses show that the stack Pt content can be reduced by 50% and the projected high-volume manufacturing cost by >45% for the stack and by 25% for the system, if the design-point system efficiency is lowered from 50% to 40%. The resulting penalties in performance are a system peak efficiency; a 2-4% decrease in the system efficiency on the urban, highway, and LA92 drive cycles; and a 6.3% decrease in the fuel economy of the modeled hybrid fuel-cell vehicle on the combined cycle used by EPA for emission and fuel economy certification. The stack heat load, however, increases by 50% at full power (80 kWe) but by only 23% at the continuous power (61.5 kWe) needed to propel the vehicle on a 6.5% grade at 55 mph. The reduced platinum and system cost advantages of further lowering the design-point efficiency from 40% to 35% are marginal. The analyses indicate that thermal management in the lower efficiency systems is very challenging and that the radiator becomes bulky if the stack temperature cannot be allowed to increase to 90-95 °C under driving conditions where heat rejection is difficult.

  18. Human pluripotent stem cell-derived products: Advances towards robust, scalable and cost-effective manufacturing strategies

    OpenAIRE

    Jenkins, M. J.; Farid, S. S.

    2015-01-01

    The ability to develop cost-effective, scalable and robust bioprocesses for human pluripotent stem cells (hPSCs) will be key to their commercial success as cell therapies and tools for use in drug screening and disease modelling studies. This review outlines key process economic drivers for hPSCs and progress made on improving the economic and operational feasibility of hPSC bioprocesses. Factors influencing key cost metrics, namely capital investment and cost of goods, for hPSCs are discusse...

  19. Low cost and high performance light trapping structure for thin-film solar cells

    CERN Document Server

    Wang, DongLin; Su, Gang

    2015-01-01

    Nano-scaled dielectric and metallic structures are popular light tapping structures in thin-film solar cells. However, a large parasitic absorption in those structures is unavoidable. Most schemes based on such structures also involve the textured active layers that may bring undesirable degradation of the material quality. Here we propose a novel and cheap light trapping structure based on the prism structured SiO2 for thin-film solar cells, and a flat active layer is introduced purposefully. Such a light trapping structure is imposed by the geometrical shape optimization to gain the best optical benefit. By examining our scheme, it is disclosed that the conversion efficiency of the flat a-Si:H thin-film solar cell can be promoted to exceed the currently certified highest value. As the cost of SiO2-based light trapping structure is much cheaper and easier to fabricate than other materials, this proposal would have essential impact and wide applications in thin-film solar cells.

  20. Investigation of Low-Cost Surface Processing Techniques for Large-Size Multicrystalline Silicon Solar Cells

    Directory of Open Access Journals (Sweden)

    Shun-Hsyung Chang

    2010-01-01

    Full Text Available The subject of the present work is to develop a simple and effective method of enhancing conversion efficiency in large-size solar cells using multicrystalline silicon (mc-Si wafer. In this work, industrial-type mc-Si solar cells with area of 125×125 mm2 were acid etched to produce simultaneously POCl3 emitters and silicon nitride deposition by plasma-enhanced chemical vapor deposited (PECVD. The study of surface morphology and reflectivity of different mc-Si etched surfaces has also been discussed in this research. Using our optimal acid etching solution ratio, we are able to fabricate mc-Si solar cells of 16.34% conversion efficiency with double layers silicon nitride (Si3N4 coating. From our experiment, we find that depositing double layers silicon nitride coating on mc-Si solar cells can get the optimal performance parameters. Open circuit (Voc is 616 mV, short circuit current (Jsc is 34.1 mA/cm2, and minority carrier diffusion length is 474.16 μm. The isotropic texturing and silicon nitride layers coating approach contribute to lowering cost and achieving high efficiency in mass production.

  1. Design, fabrication and testing of an electrolytic membrane cell to minimize the active waste generated during decontamination

    Energy Technology Data Exchange (ETDEWEB)

    Rangarajan, S.; Sumathi, S.; Balaji, V.; Puspalata, R. [BARC Facilities, Water and Steam Chemistry Div., Kalpakkam, Tamilnadu (India)

    2010-07-01

    Decontamination of the Primary Heat Transport system of the Nuclear Power Plants has become a regular exercise, carried out once in three or four years, to reduce the background radioactivity levels around the circuit and hence to control the associated man-rem budgeting. In a typical dilute chemical decontamination campaign, either a reducing or an oxidizing formulation (which depends on the nature of the oxide) containing a mixture of complexing acids are used to dissolve the surface oxides and the impregnated radioactive metal ions which are subsequently removed using ion-exchanger columns. However, this procedure not only requires many ion-exchanger columns, but also generates a large volume of active waste. By coupling suitably the ion exchange resins and electrolytic membrane cell one can effectively remove metal ions from the decontaminant formulation. This will also reduce the waste liquid volume. Apart from this, by optimizing the current-potential characteristics of the cell, one can selectively deposit / remove a particular metal ion from the other metal ions. In this paper, the design, fabrication and testing of an Electrolytic Membrane Cell containing three compartments viz., cathodic, anodic and a central feed compartment, each separated from the other by a cation-permeable nafion membrane (Na form) with Titanium cathode and a Platinum-coated Titanium anode are described in detail. Experiments were carried out with simulated decontamination solutions containing either magnetite (Fe{sub 3}O{sub 4}) or cobalt oxide (Co{sub 3}O{sub 4}) or both as a mixture in ethylene diamine tetra-acetic acid/ Nitrilo triacetic acid, ascorbic acid and citric acid (EAC / NAC) formulations, for effective removal of Co from a large quantity of Fe. The percentage of metal ion transport, pH and conductivity in the feed, catholyte and anolyte solutions were monitored as a function of electrical charge passed through the electrochemical cell. The results showed that the

  2. Design, fabrication and testing of an electrolytic membrane cell to minimize the active waste generated during decontamination

    International Nuclear Information System (INIS)

    Decontamination of the Primary Heat Transport system of the Nuclear Power Plants has become a regular exercise, carried out once in three or four years, to reduce the background radioactivity levels around the circuit and hence to control the associated man-rem budgeting. In a typical dilute chemical decontamination campaign, either a reducing or an oxidizing formulation (which depends on the nature of the oxide) containing a mixture of complexing acids are used to dissolve the surface oxides and the impregnated radioactive metal ions which are subsequently removed using ion-exchanger columns. However, this procedure not only requires many ion-exchanger columns, but also generates a large volume of active waste. By coupling suitably the ion exchange resins and electrolytic membrane cell one can effectively remove metal ions from the decontaminant formulation. This will also reduce the waste liquid volume. Apart from this, by optimizing the current-potential characteristics of the cell, one can selectively deposit / remove a particular metal ion from the other metal ions. In this paper, the design, fabrication and testing of an Electrolytic Membrane Cell containing three compartments viz., cathodic, anodic and a central feed compartment, each separated from the other by a cation-permeable nafion membrane (Na form) with Titanium cathode and a Platinum-coated Titanium anode are described in detail. Experiments were carried out with simulated decontamination solutions containing either magnetite (Fe3O4) or cobalt oxide (Co3O4) or both as a mixture in ethylene diamine tetra-acetic acid/ Nitrilo triacetic acid, ascorbic acid and citric acid (EAC / NAC) formulations, for effective removal of Co from a large quantity of Fe. The percentage of metal ion transport, pH and conductivity in the feed, catholyte and anolyte solutions were monitored as a function of electrical charge passed through the electrochemical cell. The results showed that the current obtained at an applied

  3. The cost-effectiveness and cost-utility of high-dose palliative radiotherapy for advanced non-small-cell lung cancer

    International Nuclear Information System (INIS)

    Purpose: To compute cost-effectiveness/cost-utility (CE/CU) ratios, from the treatment clinic and societal perspectives, for high-dose palliative radiotherapy treatment (RT) for advanced non-small-cell lung cancer (NSCLC) against best supportive care (BSC) as comparator, and thereby demonstrate a method for computing CE/CU ratios when randomized clinical trial (RCT) data cannot be generated. Methods and Materials: Unit cost estimates based on an earlier reported 1989-90 analysis of treatment costs at the Vancouver Island Cancer Centre, Victoria, British Columbia, Canada, are updated to 1997-1998 and then used to compute the incremental cost of an average dose of high-dose palliative RT. The incremental number of life days and quality-adjusted life days (QALDs) attributable to treatment are from earlier reported regression analyses of the survival and quality-of-life data from patients who enrolled prospectively in a lung cancer management cost-effectiveness study at the clinic over a 2-year period from 1990 to 1992. Results: The baseline CE and CU ratios are $9245 Cdn per life year (LY) and $12,836 per quality-adjusted life year (QALY), respectively, from the clinic perspective; and $12,253/LY and $17,012/QALY, respectively, from the societal perspective. Multivariate sensitivity analysis for the CE ratio produces a range of $5513-28,270/LY from the clinic perspective, and $7307-37,465/LY from the societal perspective. Similar calculations for the CU ratio produce a range of $7205-37,134/QALY from the clinic perspective, and $9550-49,213/QALY from the societal perspective. Conclusion: The cost effectiveness and cost utility of high-dose palliative RT for advanced NSCLC compares favorably with the cost effectiveness of other forms of treatment for NSCLC, of treatments of other forms of cancer, and of many other commonly used medical interventions; and lies within the US $50,000/QALY benchmark often cited for cost-effective care

  4. One step lithography-less silicon nanomanufacturing for low cost high-efficiency solar cell production

    Science.gov (United States)

    Chen, Yi; Liu, Logan

    2014-03-01

    To improve light absorption, previously various antireflection material layers were created on solar wafer surface including multilayer dielectric film, nanoparticle sludges, microtextures, noble metal plasmonic nanoparticles and 3D silicon nanostructure arrays. All of these approaches involve nanoscale prepatterning, surface-area-sensitive assembly processes or extreme fabrication conditions; therefore, they are often limited by the associated high cost and low yield as well as the consequent industry incompatibility. In comparison, our nanomanufacturing, an unique synchronized and simultaneous top-down and bottom-up nanofabrication approach called simultaneous plasma enhanced reactive ion synthesis and etching (SPERISE), offers a better antireflection solution along with the potential to increase p-n junction surface area. High density and high aspect ratio anechoic nanocone arrays are repeatedly and reliably created on the entire surface of single and poly crystalline silicon wafers as well as amorphous silicon thin films within 5 minutes under room temperature. The nanocone surface had lower than 5% reflection over the entire solar spectrum and a desirable omnidirectional absorption property. Using the nanotextured solar wafer, a 156mm × 156mm 18.1%-efficient black silicon solar cell was fabricated, which was an 18.3% enhancement over the cell fabricated by standard industrial processes. This process also reduces silicon loss during the texturing step and enables tighter process control by creating more uniform surface structures. Considering all the above advantages, the demonstrated nanomanufacturing process can be readily translated into current industrial silicon solar cell fabrication lines to replace the costly and ineffective wet chemical texturing and antireflective coatings.

  5. Off-pump or minimized on-pump coronary surgery - initial experience with Circulating Endothelial Cells (CEC as a supersensitive marker of tissue damage

    Directory of Open Access Journals (Sweden)

    Wittwer Thorsten

    2011-10-01

    Full Text Available Abstract Background Off-pump-coronary-artery-bypass-grafting (OPCAB and minimized-extracorporeal-circulation (Mini-HLM have been proposed to avoid harmful effects of cardiopulmonary-bypass (CPB. Controversies exist whether OPCAB is still superior in perioperative outcome. Circulating endothelial cells (CEC are sensitive markers of endothelial damage and are significantly elevated in conventional-CPB-procedures as compared to Mini-HLM-revascularisation. Therefore, CEC might be of specific value in evaluating effectiveness of Mini-HLM and OPCAB as currently applied less-invasive coronary procedures. Methods 76 coronary patients were randomly assigned either to OPCAB (n = 34 or to Mini-HLM (ROCsafe™, Terumo Inc., n = 42 procedures. Perioperative data, clinical and serological outcome and measurements of CEC-release and parameters of endothelial function (v.Willebrand-Factor, soluble-thrombomodulin perioperatively (pre-operative-baseline, post-Mini-HLM/release of OPCAB-stabilizer, 6 h, 12 h, 24 h and 5 days postoperatively were obtained and compared by ANOVA models including repeated-measures-analysis. Results Mean graft-number was 3.06 ± 0.72 in Mini-HLM-patients and 1.89 ± 0.74 in OPCAB-patients (p 0.05. CEC-release did not differ between groups (p = 0.274 and was generally within normal limits, Troponin-T levels where not significanty different (p = 0.108. No myocardial infarctions, strokes or deaths occurred, neuron specific enolase (NSE did not show any differences between groups (p = 0.194. Conclusion Conceptional advantages of minimized CPB systems (ROCsafe™ result in morbidity and mortality comparable with OPCAB procedures. Mini-HLM therefore minimizes CPB-related systemic and organ injury as demonstrated by low CEC-values which indicates intact endothelial integrity. Furthermore, Mini-HLM combines OPCAB-benefits with low morbidity in high-risk patients while facilitating more complete revascularization in complex patients.

  6. Montanide, Poly I:C and nanoparticle based vaccines promote differential suppressor and effector cell expansion: a study of induction of CD8 T cells to a minimal Plasmodium berghei epitope

    Directory of Open Access Journals (Sweden)

    Kirsty Lee Wilson

    2015-02-01

    Full Text Available The development of practical and flexible vaccines to target liver stage malaria parasites would benefit from an ability to induce high levels of CD8 T cells to minimal peptide epitopes. Herein we compare different adjuvant and carrier systems in a murine model for induction of interferon gamma (IFN-γ producing CD8 T cells to the minimal immuno-dominant peptide epitope from the circumsporozoite protein (CSP of Plasmodium berghei, pb9 (SYIPSAEKI, referred to as KI. Two pro-inflammatory adjuvants, Montanide and Poly I:C, and a non-classical, non-inflammatory nanoparticle based carrier (polystyrene nanoparticles, PSNPs, were compared side-by-side for their ability to induce potentially protective CD8 T cell responses after two immunisations. KI in Montanide (Montanide + KI or covalently conjugated to PSNPs (PSNPs-KI induced such high responses, whereas adjuvanting with Poly I:C or PSNPs without conjugation was ineffective. This result was consistent with an observed induction of an immunosuppressed environment by Poly I:C in the draining lymph node (dLN 48 hours post injection, which was reflected by increased frequencies of myeloid derived suppressor cells (MDSC and a proportion of inflammation reactive regulatory T cells (Treg expressing the tumour necrosis factor receptor 2 (TNFR2, as well as decreased dendritic cell (DC maturation. The other inflammatory adjuvant, Montanide, also promoted proportional increases in the TNFR2+ Treg subpopulation, but not MDSCs, in the dLN. By contrast, injection with non-inflammatory PSNPs did not cause these changes. Induction of high CD8 T cell responses, using minimal peptide epitopes, can be achieved by non-inflammatory carrier nanoparticles, which in contrast to some conventional inflammatory adjuvants, do not expand either MDSCs or inflammation reactive Tregs at the site of priming.

  7. Esophagectomy - minimally invasive

    Science.gov (United States)

    Minimally invasive esophagectomy; Robotic esophagectomy; Removal of the esophagus - minimally invasive; Achalasia - esophagectomy; Barrett esophagus - esophagectomy; Esophageal cancer - esophagectomy - laparoscopic; Cancer of the ...

  8. Exclusion of elective nodal irradiation is associated with minimal elective nodal failure in non-small cell lung cancer

    Directory of Open Access Journals (Sweden)

    Cox James D

    2009-01-01

    Full Text Available Abstract Background Controversy still exists regarding the long-term outcome of patients whose uninvolved lymph node stations are not prophylactically irradiated for non-small cell lung cancer (NSCLC treated with definitive radiotherapy. To determine the frequency of elective nodal failure (ENF and in-field failure (IFF, we examined a large cohort of patients with NSCLC staged with positron emission tomography (PET/computed tomography (CT and treated with 3-dimensional conformal radiotherapy (3D-CRT that excluded uninvolved lymph node stations. Methods We retrospectively reviewed the records of 115 patients with non-small cell lung cancer treated at our institution with definitive radiation therapy with or without concurrent chemotherapy (CHT. All patients were treated with 3D-CRT, including nodal regions determined by CT or PET to be disease involved. Concurrent platinum-based CHT was administered for locally advanced disease. Patients were analyzed in follow-up for survival, local regional recurrence, and distant metastases (DM. Results The median follow-up time was 18 months (3 to 44 months among all patients and 27 months (6 to 44 months among survivors. The median overall survival, 2-year actuarial overall survival and disease-free survival were 19 months, 38%, and 28%, respectively. The majority of patients died from DM, the overall rate of which was 36%. Of the 31 patients with local regional failure, 26 (22.6% had IFF, 5 (4.3% had ENF and 2 (1.7% had isolated ENF. For 88 patients with stage IIIA/B, the frequencies of IFF, any ENF, isolated ENF, and DM were 23 (26%, 3 (9%, 1 (1.1% and 36 (40.9%, respectively. The comparable rates for the 22 patients with early stage node-negative disease (stage IA/IB were 3 (13.6%, 1(4.5%, 0 (0%, and 5 (22.7%, respectively. Conclusion We observed only a 4.3% recurrence of any ENF and a 1.7% recurrence of isolated ENF in patients with NSCLC treated with definitive 3D-CRT without prophylactic irradiation of

  9. Vanadium oxide (VO) based low cost counter electrode in dye sensitized solar cell (DSSC) applications

    International Nuclear Information System (INIS)

    Vanadium oxide nanostars were synthesized by chemical method. The prepared Vanadium oxide nanostars are introduced into dye sensitized solar cell (DSSC) as counter electrode (CE) catalyst to replace the expensive platinum (Pt). The products were characterized by X-ray diffractometry (XRD), scanning electron microscopy (SEM), and Brunauer–Emmett–Teller (BET) method. The photovoltaic performance of the VO as counter electrode based DSSC was evaluated under simulated standard global AM 1.5G sunlight (100 mW/cm2). The solar to electrical energy conversion efficiency (η) of the DSSC was found to be 0.38%.This work expands the Counter electrode catalyst, which can help to reduce the cost of DSSC and thereby encourage their fundamental research and commercial application

  10. Treatment of Non-Small Cell Lung Cancer (NSCLC) Using CT in Combination with a PET Examination to Minimize the Clinical Target Volume of the Mediastinum

    Institute of Scientific and Technical Information of China (English)

    Yusheng Shi; Xiaogang Deng; Longhua Chen

    2007-01-01

    OBJECTIVE To decrease radiation injury of the esophagus and lungs by utilizing a CT scan in combination with PET tumor imaging in order to minimize the clinical target area of locally advanced non-small cell lung cancer, without preventive radiation on the lymphatic drainage area. METHODS Of 76 patients with locally advanced non-small cell lung cancer (NSCLC), 32 received a PET examination before radiotherapy. Preventive radiation was not conducted in the mediastinum area without lymphatic metastasis, which was confirmed by CT and PET. For the other 44 patients, preventive radiation was performed in the lymphatic drainage area. PET examinations showed that the clinical target volume of the patients was decreased on average to about one third. The radiation therapy for patients of the two groups was the same, I.e. The dose for accelerated fractionated irradiation was 3 Gy/time and 5 time/week. The preventive dose was 42 to 45 Gy/time, 14 to 15 time/week, with 3-week treatment, and the therapeutic dose was 60 to 63 Gy/time, 20 to 21 time/week, with a period of 4 to 5 weeks.RESULTS The rate of missed lymph nodes beyond the irradiation field was 6.3% and 4.5% respectively in the group with and without PET examination (P = 0.831). The incidence of acute radioactive esophagitis was 15.6 % and 45.5% in the two groups respectively (P = 0.006). The incidence of acute radiation pneumonia and long-term pulmonary fibrosis in the two groups was 6.3% and 9.1%, and 68.8% and 75.0%, respectively (P = 0.982 and P = 0.547).CONCLUSION The recurrence rate in the lymph nodes beyond the target area was not increased after minimizing the clinical target volume (CTV), whereas radioactive injury to the lungs and esophageal injury was reduced, and especially with a significant decrease in the rate of acute radioactive esophagitis. The method of CT in combination with PET for minimizing the mediastinal CTV is superior to the conventional preventive radiation of the mediastinum.

  11. Differences in practice patterns and costs between small cell and non-small cell lung cancer patients in Japan

    International Nuclear Information System (INIS)

    Many reports exist regarding the economic evaluation of evolving chemotherapeutic regimens or diagnostic images for lung cancer (LC) patients. However, it is not clear whether clinical information, such as pathological diagnosis or cancer stage, should be considered as a risk adjustment in lung cancer. This study compared the cost and practice patterns between small cell lung carcinoma (SCLC) and non-small cell lung carcinoma (NSCLC) patients. 6,060 LC patients treated at 58 academic hospitals and 14,507 at 257 community hospitals were analyzed. Study variables included demographic variables, comorbid status, cancer stage, use of imaging and surgical procedures, type of adjuvant therapy (chemotherapy, radiation or chemoradiation), use of ten chemotherapeutic agents, length of stay (LOS), and total charges (TC; US$1=100 yen) in SCLC and NSCLC patients. The impact of pathological diagnosis on LOS and TC was investigated using multivariate analysis. We identified 3,571 SCLC and 16,996 NSCLC patients. The proportion of demographic and practice-process variables differed significantly between SCLC and NSCLC patients, including diagnostic imaging, adjuvant therapy and surgical procedures. Median LOS and TC were 20 days and US$6,015 for SCLC and 18 days and US$6,993 for NSCLC patients, respectively (p<0.001 for each variable). Regression analysis revealed that pathological diagnosis was not correlated with TC. Physicians should acknowledge that pathological diagnosis dose not accounts for any variation in cost of LC patients but that should remain as an indicator of appropriate care like selection of chemotherapeutic agents. (author)

  12. Primary clear cell renal carcinoma cells display minimal mitochondrial respiratory capacity resulting in pronounced sensitivity to glycolytic inhibition by 3-Bromopyruvate.

    OpenAIRE

    Nilsson, Helén; Lindgren, David; Mandahl Forsberg, A; Mulder, Hindrik; Axelson, Håkan; Johansson, Martin

    2015-01-01

    Changes of cellular metabolism are an integral property of the malignant potential of most cancer cells. Already in the 1930s, Otto Warburg observed that tumor cells preferably utilize glycolysis and lactate fermentation for energy production, rather than the mitochondrial oxidative phosphorylation dominating in normal cells, a phenomenon today known as the Warburg effect. Even though many tumor types display a high degree of aerobic glycolysis, they still retain the activity of other energy-...

  13. Patient-individualized CD8⁺ cytolytic T-cell therapy effectively combats minimal residual leukemia in immunodeficient mice.

    Science.gov (United States)

    Distler, Eva; Albrecht, Jana; Brunk, Ariane; Khan, Shamsul; Schnürer, Elke; Frey, Michaela; Mottok, Anja; Jordán-Garrote, Ana-Laura; Brede, Christian; Beilhack, Andreas; Mades, Andreas; Tomsitz, Dirk; Theobald, Matthias; Herr, Wolfgang; Hartwig, Udo F

    2016-03-01

    Adoptive transfer of donor-derived cytolytic T-lymphocytes (CTL) has evolved as a promising strategy to improve graft-versus-leukemia (GvL) effects in allogeneic hematopoietic stem-cell transplantation. However, durable clinical responses are often hampered by limited capability of transferred T cells to establish effective and sustained antitumor immunity in vivo. We therefore analyzed GvL responses of acute myeloid leukemia (AML)-reactive CD8(+) CTL with central and effector memory phenotype in a new allogeneic donor-patient specific humanized mouse model. CTL lines and clones obtained upon stimulation of naive CD45RA(+) donor CD8(+) T cells with either single HLA antigen-mismatched or HLA-matched primary AML blasts, respectively, elicited strong leukemia reactivity during cytokine-optimized short to intermediate (i.e., 2-8 weeks) culture periods. Single doses of CTL were intravenously infused into NOD/scidIL2Rcg(null) mice when engraftment with patient AML reached bone marrow infiltration of 1-5%, clinically defining minimal residual disease status. This treatment resulted in complete regression of HLA-mismatched and strong reduction of HLA-matched AML infiltration, respectively. Most importantly, mice receiving AML-reactive CTL showed significantly prolonged survival. Transferred CTL were detectable in murine bone marrow and spleen and demonstrated sustained AML-reactivity ex vivo. Moreover, injections with human IL-15 clearly promoted CTL persistence. In summary, we show that naive donor-derived CD8(+) CTL effectively combat patient AML blasts in immunodeficient mice. The donor-patient specific humanized mouse model appears suitable to evaluate therapeutic efficacy of AML-reactive CTL before adoptive transfer into patients. It may further help to identify powerful leukemia rejection antigens and T-cell receptors for redirecting immunity to leukemias even in a patient-individualized manner. PMID:26376181

  14. Stationary fuel cells. State of the art, costs and marketing; Stationaere Brennstoffzellen. Stand der Entwicklung, Kostensituation, Marktaussichten

    Energy Technology Data Exchange (ETDEWEB)

    Wendt, H.

    2006-07-01

    Membrane fuel cells (PEMFCs), which are the cells of choice for automobiles, have too low life times, not exceeding 15.000 hours, which do not allow their application in stationary electricity generation. In contrast the high temperature cells of the molten carbonate type (MCFC) and solid oxide fuel cells (SOFC) have already been demonstrated to possess life times in excess of 30.000 hours. Most difficult to solve is the cost problem, which today seriously hampers their commercialisation in stationary systems as at least 5.500 Euro per kW must today be paid. The cost target for commercialisation, however is lower than 2.000 Euro/kW. Today phosphoric acid fuel cells (PAFC) are being further developed with the aim to reach that target. (orig.)

  15. Strategies for "minimal growth maintenance" of cell cultures: a perspective on management for extended duration experimentation in the microgravity environment of a Space station

    Science.gov (United States)

    Krikorian, A. D.

    1996-01-01

    How cells manage without gravity and how they change in the absence of gravity are basic questions that only prolonged life on a Space station will enable us to answer. We know from investigations carried out on various kinds of Space vehicles and stations that profound physiological effects can and often to occur. We need to know more of the basic biochemistry and biophysics both of cells and of whole organisms in conditions of reduced gravity. The unique environment of Space affords plant scientists an unusual opportunity to carry out experiments in microgravity, but some major challenges must be faced before this can be done with confidence. Various laboratory activities that are routine on Earth take on special significance and offer problems that need imaginative resolution before even a relatively simple experiment can be reliably executed on a Space station. For example, scientists might wish to investigate whether adaptive or other changes that have occurred in the environment of Space are retained after return to Earth-normal conditions. Investigators seeking to carry out experiments in the low-gravity environment of Space using cultured cells will need to solve the problem of keeping cultures quiescent for protracted periods before an experiment is initiated, after periodic sampling is carried out, and after the experiment is completed. This review gives an evaluation of a range of strategies that can enable one to manipulate cell physiology and curtail growth dramatically toward this end. These strategies include cryopreservation, chilling, reduced oxygen, gel entrapment strategies, osmotic adjustment, nutrient starvation, pH manipulation, and the use of mitotic inhibitors and growth-retarding chemicals. Cells not only need to be rendered quiescent for protracted periods but they also must be recoverable and further grown if it is so desired. Elaboration of satisfactory procedures for management of cells and tissues at "near zero or minimal growth" will

  16. Primary clear cell renal carcinoma cells display minimal mitochondrial respiratory capacity resulting in pronounced sensitivity to glycolytic inhibition by 3-Bromopyruvate.

    Science.gov (United States)

    Nilsson, H; Lindgren, D; Mandahl Forsberg, A; Mulder, H; Axelson, H; Johansson, M E

    2015-01-01

    Changes of cellular metabolism are an integral property of the malignant potential of most cancer cells. Already in the 1930s, Otto Warburg observed that tumor cells preferably utilize glycolysis and lactate fermentation for energy production, rather than the mitochondrial oxidative phosphorylation dominating in normal cells, a phenomenon today known as the Warburg effect. Even though many tumor types display a high degree of aerobic glycolysis, they still retain the activity of other energy-producing metabolic pathways. One exception seems to be the clear cell variant of renal cell carcinoma, ccRCC, where the activity of most other pathways than that of glycolysis has been shown to be reduced. This makes ccRCC a promising candidate for the use of glycolytic inhibitors in treatment of the disease. However, few studies have so far addressed this issue. In this report, we show a strikingly reduced mitochondrial respiratory capacity of primary human ccRCC cells, resulting in enhanced sensitivity to glycolytic inhibition by 3-Bromopyruvate (3BrPA). This effect was largely absent in established ccRCC cell lines, a finding that highlights the importance of using biologically relevant models in the search for new candidate cancer therapies. 3BrPA markedly reduced ATP production in primary ccRCC cells, followed by cell death. Our data suggest that glycolytic inhibitors such as 3BrPA, that has been shown to be well tolerated in vivo, should be further analyzed for the possible development of selective treatment strategies for patients with ccRCC. PMID:25569102

  17. Thunbergia laurifolia extract minimizes the adverse effects of toxicants by regulating P-glycoprotein activity, CYP450, and lipid metabolism gene expression in HepG2 cells.

    Science.gov (United States)

    Rocejanasaroj, A; Tencomnao, T; Sangkitikomol, W

    2014-01-01

    Thunbergia laurifolia (TL) is widely used as an antidote in Thai traditional medicine against toxic substances such as alcohol, pesticides, arsenic, and strychnine. We found that the lyophilized form of TL in 80% ethanol possessed the antioxidant levels within the range 23,163.9 ± 1457.4 Trolox equivalents mM/kg dry mass and 899.8 ± 14.5 gallic acid equivalents mM/kg dry mass using the oxygen radical absorbance capacity assay and the Folin Ciocalteu phenol assay, respectively. TL extract (TLE) at a high dose (3000 mg/L) induced cytotoxicity according to the neutral red assay and the MTT assay. However, TLE doses of 800-3000 mg/L could reduce intracellular oxidative stress in a dose-dependent manner (P CYP3A4, and PPARg, but it significantly inhibited the mRNA expression of CYP3A7, CYP2D6, and CYP2E1 (P < 0.05) by reverse transcription-polymerase chain reaction. Moreover, TLE could increase the activity of a multidrug transporter, P-glycoprotein, which accelerated the excretion of toxic substances from HepG2 cells. It is suggested that TLE may be beneficial for detoxification by reducing oxidative stress, minimizing toxicity by regulating the expression CYP450 mRNAs for suitable production of CYP450 isoenzymes, and increasing PPARγ mRNA expression and P-glycoprotein activity in HepG2 cells, thereby maintaining xenobiotic biotransformation balance. PMID:24446304

  18. Low-Cost Copper Nanostructures Impart High Efficiencies to Quantum Dot Solar Cells.

    Science.gov (United States)

    Kumar, P Naresh; Deepa, Melepurath; Ghosal, Partha

    2015-06-24

    Quantum dot solar cells (QDSCs) were fabricated using low-cost Cu nanostructures and a carbon fabric as a counter electrode for the first time. Cu nanoparticles (NPs) and nanoneedles (NNs) with a face-centered cubic structure were synthesized by a hydrothermal method and electrophoretically deposited over a CdS QD sensitized titania (TiO2) electrode. Compared to Cu NPs, which increase the light absorption of a TiO2/CdS photoanode via scattering effects only in the visible region, Cu NNs are more effective for efficient far-field light scattering; they enhance the light absorption of the TiO2/CdS assembly beyond the visible to near-infrared (NIR) regions as well. The highest fluorescence quenching, lowest excited electron lifetime, and a large surface potential (deduced from Kelvin probe force microscopy (KPFM)) observed for the TiO2/CdS/Cu NN electrode compared to TiO2/CdS and TiO2/CdS/Cu NP electrodes confirm that Cu NNs also facilitate charge transport. KPFM studies also revealed a larger shift of the apparent Fermi level to more negative potentials in the TiO2/CdS/Cu NN electrode, compared to the other two electrodes (versus NHE), which results in a higher open-circuit voltage for the Cu NN based electrode. The best performing QDSC based on the TiO2/CdS/Cu NN electrode delivers a stellar power conversion efficiency (PCE) of 4.36%, greater by 56.8% and 32.1% than the PCEs produced by the cells based on TiO2/CdS and TiO2/CdS/Cu NPs, respectively. A maximum external quantum efficiency (EQE) of 58% obtained for the cell with the TiO2/CdS/Cu NN electrode and a finite EQE in the NIR region which the other two cells do not deliver are clear indicators of the enormous promise this cheap, earth-abundant Cu nanostructure holds for amplifying the solar cell response in both the visible and near-infrared regions through scattering enhancements. PMID:26000891

  19. Prenatal screening for fetal aneuploidies with cell-free DNA in the general pregnancy population: a cost-effectiveness analysis

    Science.gov (United States)

    Fairbrother, Genevieve; Burigo, John; Sharon, Thomas; Song, Ken

    2016-01-01

    Abstract Objective: To estimate the cost-effectiveness of fetal aneuploidy screening in the general pregnancy population using non-invasive prenatal testing (NIPT) as compared to first trimester combined screening (FTS) with serum markers and NT ultrasound. Methods: Using a decision-analytic model, we estimated the number of fetal T21, T18, and T13 cases identified prenatally, the number of invasive procedures performed, corresponding normal fetus losses, and costs of screening using FTS or NIPT with cell-free DNA (cfDNA). Modeling was based on a 4 million pregnant women cohort, which represents annual births in the U.S. Results: For the general pregnancy population, NIPT identified 15% more trisomy cases, reduced invasive procedures by 88%, and reduced iatrogenic fetal loss by 94% as compared to FTS. The cost per trisomy case identified with FTS was $497 909. At a NIPT unit, cost of $453 and below, there were cost savings as compared to FTS. Accounting for additional trisomy cases identified by NIPT, a NIPT unit cost of $665 provided the same per trisomy cost as that of FTS. Conclusions: NIPT in the general pregnancy population leads to more prenatal identification of fetal trisomy cases as compared to FTS and is more economical at a NIPT unit cost of $453. PMID:26000626

  20. Efficiency in Deregulated Electricity Markets: Offer Cost Minimization vs. Payment Cost Minimization Auction

    OpenAIRE

    Rimvydas Baltaduonis

    2006-01-01

    This study of the wholesale electricity market compares the efficiency performance of the auction mechanism currently in place in U.S. markets with the performance of a proposed mechanism. The analysis highlights the importance of considering strategic behavior when comparing different institutional systems. We find that in concentrated markets, neither auction mechanism can guarantee an efficient allocation. The advantage of the current mechanism increases with increased price competition if...

  1. Forecasting the Costs of Automotive PEM Fuel Cell Systems: Using Bounded Manufacturing Progress Functions

    OpenAIRE

    Lipman, Timonthy E.; Sperling, Daniel

    2001-01-01

    The future manufacturing costs of emerging technologies are difficult to assess because of the complex dynamics of both product and process innovation, and because cost data often are proprietary and difficult to obtain. One method of forecasting potential future technology costs uses the concept of manufacturing progress functions, which are closely related to manufacturing experience curves. Manufacturing cost is related to cumulative production volume for a specific firm in an industry, us...

  2. Hybrid Organic-Inorganic Perovskites Open a New Era for Low-Cost, High Efficiency Solar Cells

    OpenAIRE

    Guiming Peng; Xueqing Xu; Gang Xu

    2015-01-01

    The ramping solar energy to electricity conversion efficiencies of hybrid organic-inorganic perovskite solar cells during the last five years have opened new doors to low-cost solar energy. The record power conversion efficiency has climbed to 19.3% in August 2014 and then jumped to 20.1% in November. In this review, the main achievements for perovskite solar cells categorized from a viewpoint of device structure are overviewed. The challenges and prospects for future development of this fiel...

  3. Very low cost thin film CdS-Cu2S solar cell development using chemical spraying

    Science.gov (United States)

    Samara, G. A.; Jordan, J. F.

    1975-01-01

    A chemical spray process for the production of thin film CdS-Cu2S solar cells is discussed that is projected to cost less than $60/kW in very large scale production. The average efficiency of these cells has been improved from less than 0.3% in 1971 about 4.5% at present. Further developments for the process are considered to raise the efficiency, and to attain long life stability.

  4. Minimally Invasive Lumbar Discectomy

    Medline Plus

    Full Text Available ... minimally invasive approach in terms of, you know, effectiveness of treating lumbar herniations? 2 Well, the minimally ... think it’s important to stress here that the effectiveness of this procedure is about the same as ...

  5. U.S. DOE Progress Towards Developing Low-Cost, High Performance, Durable Polymer Electrolyte Membranes for Fuel Cell Applications

    Directory of Open Access Journals (Sweden)

    Dimitrios C. Papageorgopoulos

    2012-12-01

    Full Text Available Low cost, durable, and selective membranes with high ionic conductivity are a priority need for wide-spread adoption of polymer electrolyte membrane fuel cells (PEMFCs and direct methanol fuel cells (DMFCs. Electrolyte membranes are a major cost component of PEMFC stacks at low production volumes. PEMFC membranes also impose limitations on fuel cell system operating conditions that add system complexity and cost. Reactant gas and fuel permeation through the membrane leads to decreased fuel cell performance, loss of efficiency, and reduced durability in both PEMFCs and DMFCs. To address these challenges, the U.S. Department of Energy (DOE Fuel Cell Technologies Program, in the Office of Energy Efficiency and Renewable Energy, supports research and development aimed at improving ion exchange membranes for fuel cells. For PEMFCs, efforts are primarily focused on developing materials for higher temperature operation (up to 120 °C in automotive applications. For DMFCs, efforts are focused on developing membranes with reduced methanol permeability. In this paper, the recently revised DOE membrane targets, strategies, and highlights of DOE-funded projects to develop new, inexpensive membranes that have good performance in hot and dry conditions (PEMFC and that reduce methanol crossover (DMFC will be discussed.

  6. U.S. DOE Progress Towards Developing Low-Cost, High Performance, Durable Polymer Electrolyte Membranes for Fuel Cell Applications.

    Science.gov (United States)

    Houchins, Cassidy; Kleen, Greg J; Spendelow, Jacob S; Kopasz, John; Peterson, David; Garland, Nancy L; Ho, Donna Lee; Marcinkoski, Jason; Martin, Kathi Epping; Tyler, Reginald; Papageorgopoulos, Dimitrios C

    2012-01-01

    Low cost, durable, and selective membranes with high ionic conductivity are a priority need for wide-spread adoption of polymer electrolyte membrane fuel cells (PEMFCs) and direct methanol fuel cells (DMFCs). Electrolyte membranes are a major cost component of PEMFC stacks at low production volumes. PEMFC membranes also impose limitations on fuel cell system operating conditions that add system complexity and cost. Reactant gas and fuel permeation through the membrane leads to decreased fuel cell performance, loss of efficiency, and reduced durability in both PEMFCs and DMFCs. To address these challenges, the U.S. Department of Energy (DOE) Fuel Cell Technologies Program, in the Office of Energy Efficiency and Renewable Energy, supports research and development aimed at improving ion exchange membranes for fuel cells. For PEMFCs, efforts are primarily focused on developing materials for higher temperature operation (up to 120 °C) in automotive applications. For DMFCs, efforts are focused on developing membranes with reduced methanol permeability. In this paper, the recently revised DOE membrane targets, strategies, and highlights of DOE-funded projects to develop new, inexpensive membranes that have good performance in hot and dry conditions (PEMFC) and that reduce methanol crossover (DMFC) will be discussed. PMID:24958432

  7. Surfactant-free CZTS nanoparticles as building blocks for low-cost solar cell absorbers

    Science.gov (United States)

    Zaberca, O.; Oftinger, F.; Chane-Ching, J. Y.; Datas, L.; Lafond, A.; Puech, P.; Balocchi, A.; Lagarde, D.; Marie, X.

    2012-05-01

    A process route for the fabrication of solvent-redispersible, surfactant-free Cu2ZnSnS4 (CZTS) nanoparticles has been designed with the objective to have the benefit of a simple sulfide source which advantageously acts as (i) a complexing agent inhibiting crystallite growth, (ii) a surface additive providing redispersion in low ionic strength polar solvents and (iii) a transient ligand easily replaced by an carbon-free surface additive. This multifunctional use of the sulfide source has been achieved through a fine tuning of ((Cu2+)a(Zn2+)b(Sn4+)c(Tu)d(OH-)e)t+, Tu = thiourea) oligomers, leading after temperature polycondensation and S2- exchange to highly concentrated (c > 100 g l-1), stable, ethanolic CZTS dispersions. The good electronic properties and low-defect concentration of the sintered, crack-free CZTSe films resulting from these building blocks was shown by photoluminescence investigation, making these building blocks interesting for low-cost, high-performance CZTSe solar cells.

  8. Surfactant-free CZTS nanoparticles as building blocks for low-cost solar cell absorbers.

    Science.gov (United States)

    Zaberca, O; Oftinger, F; Chane-Ching, J Y; Datas, L; Lafond, A; Puech, P; Balocchi, A; Lagarde, D; Marie, X

    2012-05-11

    A process route for the fabrication of solvent-redispersible, surfactant-free Cu₂ZnSnS₄ (CZTS) nanoparticles has been designed with the objective to have the benefit of a simple sulfide source which advantageously acts as (i) a complexing agent inhibiting crystallite growth, (ii) a surface additive providing redispersion in low ionic strength polar solvents and (iii) a transient ligand easily replaced by an carbon-free surface additive. This multifunctional use of the sulfide source has been achieved through a fine tuning of ((Cu²⁺)(a)(Zn²⁺)(b)(Sn⁴⁺)(c)(Tu)(d)(OH⁻)(e))(t⁺), Tu = thiourea) oligomers, leading after temperature polycondensation and S²⁻ exchange to highly concentrated (c > 100 g l⁻¹), stable, ethanolic CZTS dispersions. The good electronic properties and low-defect concentration of the sintered, crack-free CZTSe films resulting from these building blocks was shown by photoluminescence investigation, making these building blocks interesting for low-cost, high-performance CZTSe solar cells. PMID:22513652

  9. Thermally exfoliated graphene based counter electrode for low cost dye sensitized solar cells

    International Nuclear Information System (INIS)

    Graphene obtained from thermal exfoliation of graphite oxide are highly wrinkled and have large surface area. Their wrinkled nature is expected to give them excellent catalytic activity. Herein, we demonstrate the use of thermally exfoliated graphene (TEG) as cost effective electrocatalyst for the tri-iodide reduction in dye sensitized solar cells (DSSCs). X-ray diffraction, Raman and Infra red spectroscopy and electron microscopy studies confirm the defective and wrinkled nature of TEG. BET surface area measurement show a large surface area of ∼ 470 m2/g. The counter electrode was fabricated by drop casting a slurry of TEG dispersed in a Nafion:Ethanol solution on fluorine doped tin oxide (FTO) substrates. The use of Nafion prevented film ''peel off,'' thus ensuring a good substrate adhesion. Electrochemical impedance spectroscopy reveals that TEG had a catalytic performance comparable to that of Pt, suggesting its use as counter electrode material. As expected, the DSSC fabricated with Nafion solubilized TEG/FTO as counter electrode shows an efficiency of about 2.8%, comparable to Pt counter electrode based DSSC which has an efficiency of about 3.4%.

  10. Production of low cost single crystal silicon solar cells using local material and recycled Si saw-dust

    International Nuclear Information System (INIS)

    Silicon material due to its abundance in nature and maximum conversion efficiency, has a vide range of application in opto-electronic and photovoltaic devices, such as ICs, thin film transistors and solar cells. The cost of the solar cells is the main hindrance in competing solar energy with other form of energy resources. The production of Si material using locally available indigenous silicon ores will reduce the cost silicon solar cells and will help to promote solar energy applications in the country. Silicon ores, Quartz and Sand, were collected from various parts of the country and analyzed. The purification processes of Silicon to produce high purity silicon are discussed. The cost comparison of locally produced and imported silicon material shows that 15% to 20% cheaper material can be produced locally. In order to reduce the cost further, the silicon saw dust wasted during wafering process are analyzed. The undesirable impurities from silicon saw dust can be removed. The reusing of sawdust will produce 10% cheaper silicon solar cells. (author)

  11. Low-cost CdZnTe devices for cascade cell application

    Energy Technology Data Exchange (ETDEWEB)

    Basol, B.M.; Kapur, V.K. (International Solar Electric Technology, Inglewood, CA (USA))

    1990-11-01

    This report describes a research program to develop a low-cost technique for producing Cd{sub 1-x}Zn{sub x}Te devices for cascade solar cell applications. The technique involves a two-stage process for fabricating such devices with a band gap of about 1.7 eV and a transparent contact layer of low-resistivity ZnTe. In the first stage, thin films of Cd, Zn, and Te are deposited in stacked layers as Cd{sub 1-x}An{sub x}Te. The second stage involves hearing and reacting the layers to form the compound. At first, electrodeposition was used for depositing the layers to successfully fabricate Dc{sub 1-x}Zn{sub x}Te thin-film devices. These films were also intrinsically doped with copper. For the first time, transparent ZnTe films of low resistivity were obtained in a two-stage process; preliminary solar cells using films with low Zn content were demonstrated. A second phase of the project involved growing films with higher Zn content (>15%). Such films were grown on CdS-coated substrates for fabricating devices. The effects of the solar-cell processing steps on the Cd{sub 1-x}Zn{sub x}Te and CdS/Cd{sub 1-x}Zn{sub x}Te interfaces were studied; results showed that the nature of the interface depended on the stoichiometry of the Cd{sub 1-x}Zn{sub x}Te thin film. A sharp interface was observed for the CdS/CdTe structures, but the interface became highly diffused as the Zn content in the absorber layer increased above 15%. The interaction between the CdS window layer and the Cd{sub 1-x}Zn{sub x}Te absorber layer was found to result from an exchange reaction between Zn in the absorber layer and the thin CdS film. 14 refs., 10 figs.

  12. Tuberose sclerosis complex: analysis of growth rates aids differentiation of renal cell carcinoma from atypical or minimal-fat-containing angiomyolipoma

    Energy Technology Data Exchange (ETDEWEB)

    Patel, U. [Department of Radiology, St George' s Hospital, London (United Kingdom)]. E-mail: uday.patel@stgeorges.nhs.uk; Simpson, E. [Department of Radiology, St George' s Hospital, London (United Kingdom); Kingswood, J.C. [Department of Clinical Genetics, St George' s Hospital, London (United Kingdom); Saggar-Malik, A.K. [Department of Clinical Genetics, St George' s Hospital, London (United Kingdom)

    2005-06-01

    AIM: To study the radiological characteristics of renal masses in individuals with tuberous sclerosis complex (TSC) using serial CT, and to examine how renal cell carcinoma (RCC) may be differentiated from indeterminate cysts or masses. METHODS: This was a retrospective study of 12 cases of TSC in which dedicated renal CT followed after US had demonstrated cystic or sonographically unusual renal masses. The CT density of all masses was measured and the masses categorized as simple cysts, complex cysts, angiomyolipomas or indeterminate solid masses. Subjects were maintained on regular follow-up with repeat CT or MRI and interval renal US. Indeterminate masses that showed rapid growth were considered suspicious for renal cell carcinoma and biopsy or nephrectomy followed. RESULTS: Comparative data were available for a median of 4 years. In each case the renal masses were multiple and bilateral; mean mass diameter was 3.6 cm. Among a total of 206 masses, 18 were simple cysts and 3 were complex cysts. Of the complex cysts, 1 proved to be an angiomyolipoma on histology and the other 2 showed no growth. Of the solid masses, 133 were typical angiomyolipomas (AMLs) and 52 were indeterminate. On follow-up, only 3 indeterminate masses showed rapid growth (>0.5 cm/year), of which only 1 proved to be an RCC on biopsy. The other 2 were minimal-fat AMLs, and the remainder of the masses showed no or slow growth. CONCLUSION: Many renal masses associated with TSC are radiologically indeterminate. A growth threshold of >0.5 cm/year identified the only RCC in this study (0.5% of all masses). Yearly radiological follow-up of indeterminate renal masses is recommended for individuals with TSC.

  13. Tuberose sclerosis complex: analysis of growth rates aids differentiation of renal cell carcinoma from atypical or minimal-fat-containing angiomyolipoma

    International Nuclear Information System (INIS)

    AIM: To study the radiological characteristics of renal masses in individuals with tuberous sclerosis complex (TSC) using serial CT, and to examine how renal cell carcinoma (RCC) may be differentiated from indeterminate cysts or masses. METHODS: This was a retrospective study of 12 cases of TSC in which dedicated renal CT followed after US had demonstrated cystic or sonographically unusual renal masses. The CT density of all masses was measured and the masses categorized as simple cysts, complex cysts, angiomyolipomas or indeterminate solid masses. Subjects were maintained on regular follow-up with repeat CT or MRI and interval renal US. Indeterminate masses that showed rapid growth were considered suspicious for renal cell carcinoma and biopsy or nephrectomy followed. RESULTS: Comparative data were available for a median of 4 years. In each case the renal masses were multiple and bilateral; mean mass diameter was 3.6 cm. Among a total of 206 masses, 18 were simple cysts and 3 were complex cysts. Of the complex cysts, 1 proved to be an angiomyolipoma on histology and the other 2 showed no growth. Of the solid masses, 133 were typical angiomyolipomas (AMLs) and 52 were indeterminate. On follow-up, only 3 indeterminate masses showed rapid growth (>0.5 cm/year), of which only 1 proved to be an RCC on biopsy. The other 2 were minimal-fat AMLs, and the remainder of the masses showed no or slow growth. CONCLUSION: Many renal masses associated with TSC are radiologically indeterminate. A growth threshold of >0.5 cm/year identified the only RCC in this study (0.5% of all masses). Yearly radiological follow-up of indeterminate renal masses is recommended for individuals with TSC

  14. Regularity of Minimal Surfaces

    CERN Document Server

    Dierkes, Ulrich; Tromba, Anthony J; Kuster, Albrecht

    2010-01-01

    "Regularity of Minimal Surfaces" begins with a survey of minimal surfaces with free boundaries. Following this, the basic results concerning the boundary behaviour of minimal surfaces and H-surfaces with fixed or free boundaries are studied. In particular, the asymptotic expansions at interior and boundary branch points are derived, leading to general Gauss-Bonnet formulas. Furthermore, gradient estimates and asymptotic expansions for minimal surfaces with only piecewise smooth boundaries are obtained. One of the main features of free boundary value problems for minimal surfaces is t

  15. Radically altered T cell receptor signaling in glycopeptide-specific T cell hybridoma induced by antigen with minimal differences in the glycan group

    DEFF Research Database (Denmark)

    Jensen, T; Nielsen, M; Gad, Monika;

    2001-01-01

    A T cell hybridoma raised against the synthetic glycopeptide T(72)(Tn) was used to study whether the initial TCR signaling events are markedly different when the hybridoma is stimulated with glycopeptides closely related to the cognate glycopeptide antigen. T(72)(Tn) has an alpha-D-GalNAc group O......-linked to the central threonine in the decapeptide VITAFTEGLK, and the hybridoma is known to be highly specific for this carbohydrate group. T(72)(Tn)-pulsed APC induced tyrosine phosphorylation of the TCR-zeta 21- and 23-kDa proteins and the downstream p42/44 MAP kinase and strong IL-2 secretion. APC...

  16. Outcomes and costs of autologous stem cell mobilization with chemotherapy plus G-CSF versus G-CSF alone

    OpenAIRE

    Sung, Anthony D.; Grima, Daniel T; Bernard, Lisa M.; Brown, Stephen; Carrum, George; Holmberg, Leona; Horwitz, Mitchell E.; Liesveld, Jane L.; Kanda, Junya; McClune, Brian; Shaughnessy, Paul; Tricot, Guido J.; Nelson J Chao

    2013-01-01

    Chemotherapy plus granulocyte colony stimulating factor (G-CSF) (C+G) and G-CSF alone are two of the most common methods of mobilizing CD34+ cells for autologous hematopoietic stem cell transplantation (AHSCT). In order to compare and determine real-world outcomes and costs of these strategies, we performed a retrospective study of 226 consecutive patients at 11 medical centers (64 lymphoma, 162 multiple myeloma), of whom 55% and 66% received C+G. Patients with C+G collected more CD34+ cells/...

  17. The Investigation and Development of Low Cost Hardware Components for Proton-Exchange Membrane Fuel Cells - Final Report

    Energy Technology Data Exchange (ETDEWEB)

    George A. Marchetti

    1999-12-15

    Proton exchange membrane (PEM) fuel cell components, which would have a low-cost structure in mass production, were fabricated and tested. A fuel cell electrode structure, comprising a thin layer of graphite (50 microns) and a front-loaded platinum catalyst layer (600 angstroms), was shown to produce significant power densities. In addition, a PEM bipolar plate, comprising flexible graphite, carbon cloth flow-fields and an integrated polymer gasket, was fabricated. Power densities of a two-cell unit using this inexpensive bipolar plate architecture were shown to be comparable to state-of-the-art bipolar plates.

  18. Cost-effectiveness analysis of paclitaxel + carboplatin vs. alternative combinations in the treatment of non-small cell lung cancer

    Directory of Open Access Journals (Sweden)

    Mario Eandi

    2006-06-01

    Full Text Available Non-small cell lung cancer (NSCLC is the most common type of lung cancer and its medical and economical burden represents a serious matter in Europe and Usa, due to its high mortality rates and drug costs. Lung cancer is responsible for about 30% of cancer death in men and women; in Europe only about 8 per cent of people with lung cancer survive for 5 years. At present combination chemotherapy based on cisplatin or carboplatin associated with paclitaxel, vinorelbine or gemcitabine is the state of the art for the treatment in patients with stage IIIb or IV NSCLC. Aim of this study was to compare the cost-effectiveness of paclitaxel/carboplatin (PCb, gemcitabine/cisplatin (GC and vinorelbine/cisplatin (VC in the perspective of the Italian National Health Service. Therefore we perfomed a semi-Markov decision model mainly based on clinical results from the Italian Lung Cancer Project. The model included differential direct medical costs registered for two years from starting chemotherapy, using tariffs valid for 2005. Benefits was measured by years of life saved (YOLs. The model also allowed to estimate only costs accrued over the period of time, performing a cost-minimisation analysis. According to cost-effectiveness analysis, VC is dominated because it’s more costly and less effective than GC. On the contrary, combination chemotherapy with GC is more inexpensive but less effective than paclitaxel/carboplatin (PCb: in this case we compared the incremental cost-effectiveness ratio (ICER with a maximum acceptable willingness-to-pay (WTP value. In the base scenario the ICER of PCb over GC treatment is 52,326 euro/ YOLs, which is definitely lower than the maximum acceptable WTP value. Sensitivity analyses confirmed the robustness of the results from cost-effectiveness analysis in the base scenario.

  19. Retrospective claims analysis of best supportive care costs and survival in a US metastatic renal cell population

    Directory of Open Access Journals (Sweden)

    Henk HJ

    2013-07-01

    Full Text Available Henry J Henk,1 Connie Chen,2 Agnes Benedict,3 Jane Sullivan,1 April Teitelbaum1 1Optum, Eden Prairie, MN, USA; 2Pfizer Inc, New York, NY, USA; 3United BioSource Corporation, London, UK Introduction: Survival and best supportive care (BSC costs for patients with metastatic renal cell carcinoma (mRCC, after stopping therapy, are poorly characterized yet an important aspect of patient care. This study examined survival and costs associated with BSC after one or two lines of therapy (LOTs for mRCC. Methods: A retrospective cohort analysis used claims data from commercially insured or Medicare Advantage Prescription Drug (MAPD plan enrollees of a large United States health plan with an index RCC diagnosis (ICD-9-CM 189.0 between January 1, 2007 and June 30, 2010; initiating any of the following therapies 30 days pre-index date through disenrollment from plan: sunitinib, temsirolimus, sorafenib, bevacizumab, everolimus, pazopanib, cytokines. LOT was identified using prescription fill and administration dates. Health care costs represent health plan- plus patient-paid amounts. Results: The cohort (n = 274 was 73% male, with a mean age of 63.3 years (SD 11.1, with 80% commercially insured (20% MAPD, and 68% starting BSC following one LOT. Mean BSC duration was longer following one than two LOTs (223 [SD 260], 176 [SD 163] days. Median survival from the start of BSC was similar following one and two LOTs (126 and 118 days. Total BSC costs following one and two LOTs averaged US$50,188 (SD $96,984 and $37,295 (SD $51,102. Monthly costs for BSC following one and two LOTs ($10,151 and $10,566 were not substantially lower than costs while on treatment ($14,621 and $16,957. Inpatient hospital costs represented 47% and 49% following one and two LOTs, with ambulatory costs of approximately 36% following each LOT. Conclusion: Our study found similar survival and monthly costs for BSC following either one or two LOTs, with almost half of the cost reflecting

  20. Minimização do custo H∞ de sistemas incertos discretos no tempo com atraso nos estados H∞ cost minimization of uncertain discrete time systems with delay in the state

    Directory of Open Access Journals (Sweden)

    André F. Caldeira

    2011-06-01

    Full Text Available Neste trabalho são investigados sistemas lineares incertos e discretos no tempo com atraso variante no tempo afetando o vetor de estados. É considerado que as incertezas são representadas em um domínio politópico e que elas podem estar presentes em todas as matrizes do modelo do sistema. Condições expressas como Desigualdades Matriciais Lineares (LMIs, do inglês Linear Matrix Inequalities são propostas para o cômputo do custo garantido H∞ e para a síntese de ganhos robustos de realimentação de estados que minimizam a norma H∞ entre a entrada de pertubação e a saída do sistema. Essas condições são estabelecidas com a utilização de funções de Lyapunov-Krasovskii (L-K dependentes de parâmetro. Variáveis matriciais de folga - via Lema de Finsler - são empregadas para desacoplar as matrizes do sistema das matrizes da função de L-K. A "desigualdade de Jensen" é usada para manipular os termos cruzados que aparecem no desenvolvimento das condições, fornecendo uma majoração menos conservadora que outras encontradas na literatura. As condições propostas são dependentes do atraso. Exemplos numéricos são apresentados para ilustrar a eficácia da proposta e para estabelecer comparações com outras encontradas na literatura.This paper deals with uncertain discrete-time systems with time varying delay affecting the state vector. It is considered that the uncertainties are represented in a polytopic domain and they may be present in all matrices of the model of the system. Conditions expressed as Linear Matrix Inequalities (LMIs are proposed for the H∞ guaranteed cost computation and for the design of robust state feedback control gains that minimize the H∞ norm from the perturbation input to the system output. These conditions are established by using parameter dependent Lyapunov-Krasovskii (L-K functions. Slack matrix variables - via Finsler's Lemma - are employed to decouple the matrices of the system from the L

  1. Minimum cost connection networks

    DEFF Research Database (Denmark)

    Hougaard, Jens Leth; Tvede, Mich

    In the present paper we consider the allocation of cost in connection networks. Agents have connection demands in form of pairs of locations they want to be connected. Connections between locations are costly to build. The problem is to allocate costs of networks satisfying all connection demands....... We use three axioms to characterize allocation rules that truthfully implement cost minimizing networks satisfying all connection demands in a game where: (1) a central planner announces an allocation rule and a cost estimation rule; (2) every agent reports her own connection demand as well as all...... connection costs; and, (3) the central planner selects a cost minimizing network satisfying reported connection demands based on estimated connection costs and allocates true connection costs of the selected network....

  2. Minimum cost connection networks

    DEFF Research Database (Denmark)

    Hougaard, Jens Leth; Tvede, Mich

    2015-01-01

    In the present paper we consider the allocation of costs in connection networks. Agents have connection demands in form of pairs of locations they want to have connected. Connections between locations are costly to build. The problem is to allocate costs of networks satisfying all connection...... demands. We use a few axioms to characterize allocation rules that truthfully implement cost minimizing networks satisfying all connection demands in a game where: (1) a central planner announces an allocation rule and a cost estimation rule; (2) every agent reports her own connection demand as well...... as all connection costs; (3) the central planner selects a cost minimizing network satisfying reported connection demands based on the estimated costs; and, (4) the planner allocates the true costs of the selected network. It turns out that an allocation rule satisfies the axioms if and only if relative...

  3. Tandem Microwire Solar Cells for Flexible High Efficiency Low Cost Photovoltaics

    Energy Technology Data Exchange (ETDEWEB)

    Atwater, Harry A. [California Institute of Technology, Pasadena, CA (United States)

    2015-03-10

    This project has developed components of a waferless, flexible, low-cost tandem multijunction III-V/Si microwire array solar cell technology which combines the efficiency of wafered III-V photovoltaic technologies with the process designed to meet the Sunshot object. The project focused on design of lattice-matched GaAsP/SiGe two junction cell design and lattice-mismatched GaInP/Si tandem cell design. Combined electromagnetic simulation/device physics models using realistic microwire tandem structures were developed that predict >22% conversion efficiency for known material parameters, such as tunnel junction structure, window layer structure, absorber lifetimes and optical absorption and these model indicate a clear path to 30% efficiency for high quality III-V heterostructures. SiGe microwire arrays were synthesized via Cu-catalyzed vapor-liquid-solid (VLS) growth with inexpensive chlorosilane and chlorogermance precursors in an atmospheric pressure reactor. SiGe alloy composition in microwires was found to be limited to a maximum of 12% Ge incorporation during chlorogermane growth, due to the melting of the alloy near the solidus composition. Lattice mismatched InGaP double heterostructures were grown by selective epitaxy with a thermal oxide mask on Si microwire substrates using metallorganic vapor phase epitaxy. Transmission electron microscopy (TEM) analysis confirms the growth of individual step graded layers and a high density of defects near the wire/III-V interface. Selective epitaxy was initiated with a low temperature nucleation scheme under “atomic layer epitaxy” or “flow mediated epitaxy” conditions whereby the Ga and P containing precursors are alternately introduced into the reactor to promote layer-bylayer growth. In parallel to our efforts on conformal GaInP heteroepitaxy on selectively masked Si microwires, we explored direct, axial growth of GaAs on Si wire arrays as another route to a tandem junction architecture. We proposed axial

  4. Low-cost, heated, and/or cooled flow-through cell for transmission x-ray absorption spectroscopy

    Science.gov (United States)

    Jentoft, R. E.; Deutsch, S. E.; Gates, B. C.

    1996-06-01

    A transmission x-ray absorption spectroscopy cell that can be used for air-sensitive samples with in situ treatment is described. The cell is designed with a relatively small size for use with air-sensitive powdered catalyst samples that must be loaded in a glove box. Samples can be treated in situ with gas flow or vacuum and temperature control up to 500 °C. The cell is constructed of stainless steel and designed for durability as well as ease of repair. The cells are vacuum tight and equipped with beryllium windows sealed with vacuum O-ring flanges for easy loading. Each cell, with all parts excluding the windows, costs about 2700.

  5. TCO-free, flexible, and bifacial dye-sensitized solar cell based on low-cost metal wires

    Energy Technology Data Exchange (ETDEWEB)

    Fu, Yongping; Lv, Zhibin; Hou, Saocong; Wu, Hongwei; Wang, Dan; Zhang, Chao; Zou, Dechun [Beijing National Laboratory for Molecular Sciences (China). Key Laboratory of Polymer Chemistry and Physics of Ministry of Education, College of Chemistry and Molecular Engineering; Peking University, Beijing (China)

    2012-01-15

    A flexible, dye-sensitized solar cell based on low-cost metal fibers as the substrates is designed. This cell provides a breakthrough on the traditional sandwich-type flat-cell structure. It has good flexibility even without a transparent conductive oxide. Moreover, the new solar cell can generate electric power with illumination on in either side, and mass production is possible using weaving technology. At present, the efficiency of 1.50 cm{sup 2} of the solar-cell module under AM 1.5 G (100 mW cm{sup -2}) reaches 2.41%. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  6. Synthetic fuel production costs by means of solid oxide electrolysis cells

    DEFF Research Database (Denmark)

    Ridjan, Iva; Mathiesen, Brian Vad; Connolly, David

    2014-01-01

    results confirm that synthetic fuel pathways reduce the demand for biomass, while simultaneously increasing the flexibility of the energy system by enabling a high share of wind energy. The most interesting finding is that the production costs of synthetic fuels are comparable with petrol production costs...

  7. Minimal Identifiable Disease and the Role of Conditioning Intensity in Hematopoietic Cell Transplantation for Myelodysplastic Syndrome and Acute Myelogenous Leukemia Evolving from Myelodysplastic Syndrome.

    Science.gov (United States)

    Festuccia, Moreno; Deeg, H Joachim; Gooley, Theodore A; Baker, Kelsey; Wood, Brent L; Fang, Min; Sandmaier, Brenda M; Scott, Bart L

    2016-07-01

    Allogeneic hematopoietic cell transplantation (HCT) is the only known treatment with curative potential for myelodysplastic syndrome, but relapse is a major cause of failure. We studied results in 289 patients transplanted between June 2004 and December 2013. Minimal identifiable disease (MID) markers pre-HCT were determined by multiparameter flow cytometry (MFC) and cytogenetics on marrow aspirates. The impact of MID on outcome after low- and high-intensity conditioning HCT was determined. Among 287 assessable patients, 68 (23.7%) had more than 5% marrow blasts at HCT; 219 patients were in morphologic remission but 154 (53.7%) were MID positive, whereas 65 (22.6%) were MID negative. The impact of MID on outcome was significantly different between patients who received low-intensity conditioning and patients who received a high-intensity regimen. The impact of conditioning intensity differed across the various MID categories. In particular, the risk of overall mortality was higher with low-intensity than with high-intensity regimens for patients who were positive for MID by cytogenetics regardless of positivity by MFC (HR, 1.67 if MFC positive/cytogenetics positive, HR, 7.23 if MFC negative/cytogenetics positive). On the other hand, patients who were MID negative by both MFC and cytogenetics had similar risks of mortality with low- and high-intensity regimens (HR, .99). The main factor responsible for mortality after low-intensity conditioning in MID-positive patients was relapse. The presence of MID should be considered when deciding on conditioning intensity because it identifies subgroups of patients who may benefit from high- or low-intensity conditioning. PMID:27064057

  8. Waste minimization in analytical methods

    International Nuclear Information System (INIS)

    The US Department of Energy (DOE) will require a large number of waste characterizations over a multi-year period to accomplish the Department's goals in environmental restoration and waste management. Estimates vary, but two million analyses annually are expected. The waste generated by the analytical procedures used for characterizations is a significant source of new DOE waste. Success in reducing the volume of secondary waste and the costs of handling this waste would significantly decrease the overall cost of this DOE program. Selection of appropriate analytical methods depends on the intended use of the resultant data. It is not always necessary to use a high-powered analytical method, typically at higher cost, to obtain data needed to make decisions about waste management. Indeed, for samples taken from some heterogeneous systems, the meaning of high accuracy becomes clouded if the data generated are intended to measure a property of this system. Among the factors to be considered in selecting the analytical method are the lower limit of detection, accuracy, turnaround time, cost, reproducibility (precision), interferences, and simplicity. Occasionally, there must be tradeoffs among these factors to achieve the multiple goals of a characterization program. The purpose of the work described here is to add waste minimization to the list of characteristics to be considered. In this paper the authors present results of modifying analytical methods for waste characterization to reduce both the cost of analysis and volume of secondary wastes. Although tradeoffs may be required to minimize waste while still generating data of acceptable quality for the decision-making process, they have data demonstrating that wastes can be reduced in some cases without sacrificing accuracy or precision

  9. Esophagectomy - minimally invasive

    Science.gov (United States)

    ... Robotic esophagectomy; Removal of the esophagus - minimally invasive; Achalasia - esophagectomy; Barrett esophagus - esophagectomy; Esophageal cancer - esophagectomy - laparoscopic; Cancer of the esophagus -esophagectomy - ...

  10. On EOQ cost models with arbitrary purchase and transportation costs

    OpenAIRE

    Birbil, Ş. İlker; Birbil, S. Ilker; Bülbül, Kerem; Bulbul, Kerem; Frenk, Hans; Mulder, H.M.

    2015-01-01

    We analyze an economic order quantity cost model with unit out-of-pocket holding costs, unit opportunity costs of holding, fixed ordering costs, and general purchase-transportation costs. We identify the set of purchase-transportation cost functions for which this model is easy to solve and related to solving a one-dimensional convex minimization problem. For the remaining purchase-transportation cost functions, when this problem becomes a global optimization problem, we propose a Lipschitz o...

  11. The CellFlux storage concept for cost reduction in parabolic trough solar thermal power plants

    OpenAIRE

    Odenthal, Christian; Steinmann, Wolf-Dieter; Eck, Markus; Laing, Doerte

    2013-01-01

    Although facility scale thermal energy storage of sensible heat in the range of 200-600°C has achieved a high maturity, state-of-the-art approaches are still not very cost effective. An innovative storage concept is thus proposed here that avoids the two major cost-driving factors of the concrete storage and 2-tank molten salt systems. First, the storage volume is comprised of low-cost sensible storage material such as concrete, natural stone or clinker bricks. These materials are several tim...

  12. Development of an energy consumption and cost data base for fuel cell total energy systems and conventional building energy systems

    Science.gov (United States)

    Pine, G. D.; Christian, J. E.; Mixon, W. R.; Jackson, W. L.

    1980-07-01

    The procedures and data sources used to develop an energy consumption and system cost data base for use in predicting the market penetration of phosphoric acid fuel cell total energy systems in the nonindustrial building market are described. A computer program was used to simulate the hourly energy requirements of six types of buildings; office buildings; retail stores; hotels and motels; schools; hospitals; and multifamily residences. The simulations were done by using hourly weather tapes for one city in each of the ten Department of Energy administrative regions. Two types of building construction were considered, one for existing buildings and one for new buildings. A fuel cell system combined with electrically driven heat pumps and one combined with a gas boiler and an electrically driven chiller were compared with similar conventional systems. The methods of system simulation, component sizing, and system cost estimation are described for each system.

  13. Cost Effectiveness of Positron Emission Tomography for the Management of Potentially Operable Non-Small Cell Lung Cancer in Quebec

    OpenAIRE

    Van Hung Nguyen; Serge Péloquin; Yves Lacasse

    2005-01-01

    BACKGROUND: The potential benefits of positron emission tomography (PET) scanning stem from the fact that it can reduce the number of diagnostic examinations; particularly, the number of unnecessary thoracic surgeries.OBJECTIVE: To evaluate the economic impact and cost-effectiveness of PET scanning in the management of potentially operable non-small cell lung cancer in Quebec.METHODS: A decision tree was developed. Two strategies were compared: chest computed tomography (CT) alone or CT and w...

  14. Hybrid Organic-Inorganic Perovskites Open a New Era for Low-Cost, High Efficiency Solar Cells

    Directory of Open Access Journals (Sweden)

    Guiming Peng

    2015-01-01

    Full Text Available The ramping solar energy to electricity conversion efficiencies of hybrid organic-inorganic perovskite solar cells during the last five years have opened new doors to low-cost solar energy. The record power conversion efficiency has climbed to 19.3% in August 2014 and then jumped to 20.1% in November. In this review, the main achievements for perovskite solar cells categorized from a viewpoint of device structure are overviewed. The challenges and prospects for future development of this field are also briefly presented.

  15. Cost-Efficient Thermophotovoltaic Cells based on Germanium (Kostefficiënte thermofotovoltaïsche cellen gebaseerd op germanium)

    OpenAIRE

    van der Heide, Johan

    2009-01-01

    This thesis describes the realisation of cost-efficient thermophotovolta ic cells based on germanium substrates. Because the majority of the incoming phot ons will have a long wavelength it is important to apply optical confinement on the TPV cell. In this thesis this has been done by using a highly reflective rear contact. Electrical contact has been created at the rear with a laser (LFC) such that the metal is locally heated and contact is formed at the rear of the cel l. This applicat...

  16. Minimizing Mutual Couping

    DEFF Research Database (Denmark)

    2010-01-01

    Disclosed herein are techniques, systems, and methods relating to minimizing mutual coupling between a first antenna and a second antenna.......Disclosed herein are techniques, systems, and methods relating to minimizing mutual coupling between a first antenna and a second antenna....

  17. Aluminium alloyed iron-silicide/silicon solar cells: A simple approach for low cost environmental-friendly photovoltaic technology

    Science.gov (United States)

    Kumar Dalapati, Goutam; Masudy-Panah, Saeid; Kumar, Avishek; Cheh Tan, Cheng; Ru Tan, Hui; Chi, Dongzhi

    2015-12-01

    This work demonstrates the fabrication of silicide/silicon based solar cell towards the development of low cost and environmental friendly photovoltaic technology. A heterostructure solar cells using metallic alpha phase (α-phase) aluminum alloyed iron silicide (FeSi(Al)) on n-type silicon is fabricated with an efficiency of 0.8%. The fabricated device has an open circuit voltage and fill-factor of 240 mV and 60%, respectively. Performance of the device was improved by about 7 fold to 5.1% through the interface engineering. The α-phase FeSi(Al)/silicon solar cell devices have promising photovoltaic characteristic with an open circuit voltage, short-circuit current and a fill factor (FF) of 425 mV, 18.5 mA/cm2, and 64%, respectively. The significant improvement of α-phase FeSi(Al)/n-Si solar cells is due to the formation p+-n homojunction through the formation of re-grown crystalline silicon layer (~5-10 nm) at the silicide/silicon interface. Thickness of the regrown silicon layer is crucial for the silicide/silicon based photovoltaic devices. Performance of the α-FeSi(Al)/n-Si solar cells significantly depends on the thickness of α-FeSi(Al) layer and process temperature during the device fabrication. This study will open up new opportunities for the Si based photovoltaic technology using a simple, sustainable, and los cost method.

  18. Minimally Invasive Treatment for Lung Cancer

    Medline Plus

    Full Text Available ... in between the ribs. We divide just the soft tissue of the thorax, the chest wall. And, ... therapy is is the use of high-energy X-rays that preferentially kill cancer cells with minimal damage ...

  19. Minimally Invasive Treatment for Lung Cancer

    Medline Plus

    Full Text Available ... rigid instruments that are applicable in an earlier generation of thoracic and thoracoscopic devices and definitely better ... therapy is is the use of high-energy X-rays that preferentially kill cancer cells with minimal ...

  20. Minimally Invasive Treatment for Lung Cancer

    Medline Plus

    Full Text Available ... glucose into the patient’s body and the cancer cells, you know, take up glucose more than the regular cells in the body, and it will give us ... high-energy X-rays that preferentially kill cancer cells with minimal damage overall to the normal surrounding ...

  1. Cost of fuel cell systems on a mass basis as a function of production volume; Kosten von Brennstoffzellensystemen auf Massenbasis in Abhaengigkeit von der Absatzmenge

    Energy Technology Data Exchange (ETDEWEB)

    Werhahn, Johannes

    2009-07-01

    The currently high cost of fuel cells is determined by expensive materials and low production volume. A detailed understanding of the cost structures reveals unexploited potential that can reduce costs in future. However, this requires a method of predicting costs that can be applied with little effort and which offers both a sufficient degree of detail and also good accuracy. Existing forecasting methods do not, however, fulfil these requirements. The major objective of the present work was to apply mass-specific cost forecasting to fuel cell systems for the first time and to modify the approach for this application. In this method, the cost of an object is estimated solely by means of the object mass with the aid of empirical values (Euro/kg). The advantages of the method are its simple application and the accuracy of the forecast. Due to the considerable complexity of the fuel cell and the heterogeneity of the materials used, the application of mass-specific cost forecasting does not provide the desired benefits on the level of the aggregated system. The mass-specific cost forecast approach was therefore expanded and optimized. Instead of determining costs on the level of the aggregated system, the cost forecast was applied directly to the individual components. Cost parameters were also embedded in the method in order to include component-internal cost-relevant differences. Due to the great influence of the production rate on the manufacturing costs, an additional dependence on number of units was also integrated. Expanding the empirical values from discrete values to distribution functions enabled a detailed error analysis to be performed and also a statistical localization of the predicted production costs. Empirical values are necessary in order to implement the modified method and therefore an extensive data search was performed. To this end, a methodology was developed which comprehensively described the data acquisition and the required data evaluation on

  2. Understanding and development of cost-effective industrial aluminum back surface field (Al-BSF) silicon solar cells

    Science.gov (United States)

    Chen, Nian

    For the long-term strategy of gradual decarbonization of the world's energy supply, high penetration of PV electricity is critical in the future world energy landscape. In order to achieve this, solar electricity with competitive cost to fossil fuel energy is necessary. To be able to obtain high efficiency solar cells, many advanced cell architectures have been developed commercially by PV industry. However, the fabrication of these cells necessitates complex processing steps and high requirements on semiconductor materials, which make it not as cost-effective as the state-of-the-art conventional Al-BSF structure. In order to keep the cost of PV cell low and improve on the efficiency with fewer processing steps, this thesis work focuses on the understanding of the conventional Al-BSF solar cell structure. The research work therefore, focuses on the (i) design, and modeling of front metal electrodes including the use of multi-bus-bar capable of decreasing the gridline resistance, (ii) fine-line printing and (iii) metal contact co-firing using high belt speed that is not common to the solar industry to achieve ~20% efficient industrial Al-BSF silicon solar cells. In order to achieve the objectives of this thesis work, firstly, the appropriate Al paste was investigated for lowest back surface recombination velocity (BSRV), which gives high open circuit voltage (Voc). Secondly, the impact of emitter sheet resistance on solar cell performance was modeled to determine the optimal sheet resistance, and the uniformity of emitter was also investigated. Thirdly, modeling on the front metal electrodes was carried out to investigate the optimal number of busbars, and determine the optimum number of gridlines and gridline geometries that would result in low series resistance (Rs), high fill factor (FF) and hence high efficiency. Fourthly, the modeled results were experimentally validated through fine-line printing and optimized contact co-firing. By combining each layer to make

  3. Progress in low-cost n-type silicon solar cell technology

    Energy Technology Data Exchange (ETDEWEB)

    Geerligs, L.J.; Romijn, G.; Burgers, A.R.; Guillevin, N.; Weeber, A.W.; Bultman, J.H. [ECN Solar Energy, Petten (Netherlands); Wang, Hongfang; Lang, Fang; Zhao, Wenchao; Li, Gaofei; Hu, Zhiyan; Xiong, Jingfeng [Yingli Green Energy Holding Co., LTD, Baoding (China); Vlooswijk, A. [Tempress Systems, Vaassen (Netherlands)

    2012-06-15

    This article will review our recent progress in development of high-efficiency cells on n-type monocrystalline Si wafers. With boron-doped front emitter, phosphorous BSF, and screen-printed metallisation, at this moment such cells reach an efficiency of over 19%. We describe recent results of processing with reduced front contact area, and improved BSF and improved rear surface passivation, which are key parameters that limit the cell efficiency. The improved processing leads to an efficiency of 20%. The cell process has also been adopted for fabrication of metal-wrap-through back-contact cells. Without the improved contact recombination and BSF, an MWT cell efficiency of 19.7% is reached, 0.3% higher than the corresponding 'standard' (non-back-contact) cells.

  4. Cost-effectiveness of FDG-PET in staging non-small cell lung cancer: the PLUS study

    Energy Technology Data Exchange (ETDEWEB)

    Verboom, Paul; Grijseels, E.W.M; Uyl-de Groot, Carin A. [Institute for Medical Technology Assessment, Erasmus Medical Centre/Erasmus University Rotterdam, P.O. Box 1738, 3000 DR, Rotterdam (Netherlands); Tinteren, Harm van; Diepenhorst, Fred W. [Comprehensive Cancer Centre Amsterdam (Netherlands); Hoekstra, Otto S. [Department of Nuclear Medicine, Vrije Universiteit Medical Centre, Amsterdam (Netherlands); Department of Clinical Epidemiology and Biostatistics, Vrije Universiteit Medical Centre, Amsterdam (Netherlands); Smit, Egbert F.; Postmus, Pieter E. [Department of Pulmonology, Vrije Universiteit Medical Centre, Amsterdam (Netherlands); Bergh, Jan H.A.M. van den; Velthoven, Piet C.M. van [Department of Pulmonology, Medical Centre Alkmaar (Netherlands); Schreurs, Ad J.M. [Department of Pulmonology, Onze Lieve Vrouwe Gasthuis, Amsterdam (Netherlands); Stallaert, Roland A.L.M. [Department of Pulmonology, Westfries Gasthuis (Netherlands); Comans, Emile F.I.; Teule, Gerrit J.J. [Department of Nuclear Medicine, Vrije Universiteit Medical Centre, Amsterdam (Netherlands); Mourik, Johan C. van [Department of Surgery, Vrije Universiteit Medical Centre, Amsterdam (Netherlands); Boers, Maarten [Department of Clinical Epidemiology and Biostatistics, Vrije Universiteit Medical Centre, Amsterdam (Netherlands)

    2003-11-01

    Currently, up to 50% of the operations in early-stage non-small cell lung cancer (NSCLC) are futile owing to the presence of locally advanced tumour or distant metastases. More accurate pre-operative staging is required in order to reduce the number of futile operations. The cost-effectiveness of fluorine-18 fluorodeoxyglucose positron emission tomography ({sup 18}FDG-PET) added to the conventional diagnostic work-up was studied in the PLUS study. Prior to invasive staging and/or thoracotomy, 188 patients with (suspected) NSCLC were randomly assigned to conventional work-up (CWU) and whole-body PET or to CWU alone. CWU was based on prevailing guidelines. Pre-operative staging was followed by 1 year of follow-up. Outcomes are expressed in the percentage of correctly staged patients and the associated costs. The cost price of PET varied between and euro;736 and and euro;1,588 depending on the (hospital) setting and the procurement of {sup 18}FDG commercially or from on-site production. In the CWU group, 41% of the patients underwent a futile thoracotomy, whereas in the PET group 21% of the thoracotomies were considered futile (P=0.003). The average costs per patient in the CWU group were and euro;9,573 and in the PET group, and euro;8,284. The major cost driver was the number of hospital days related to recovery from surgery. Sensitivity analysis on the cost and accuracy of PET showed that the results were robust, i.e. in favour of the PET group. The addition of PET to CWU prevented futile surgery in one out of five patients with suspected NSCLC. Despite the additional PET costs, the total costs were lower in the PET group, mainly due to a reduction in the number of futile operations. The additional use of PET in the staging of patients with NSCLC is feasible, safe and cost saving from a clinical and from an economic perspective. (orig.)

  5. Cost-effectiveness of FDG-PET in staging non-small cell lung cancer: the PLUS study

    International Nuclear Information System (INIS)

    Currently, up to 50% of the operations in early-stage non-small cell lung cancer (NSCLC) are futile owing to the presence of locally advanced tumour or distant metastases. More accurate pre-operative staging is required in order to reduce the number of futile operations. The cost-effectiveness of fluorine-18 fluorodeoxyglucose positron emission tomography (18FDG-PET) added to the conventional diagnostic work-up was studied in the PLUS study. Prior to invasive staging and/or thoracotomy, 188 patients with (suspected) NSCLC were randomly assigned to conventional work-up (CWU) and whole-body PET or to CWU alone. CWU was based on prevailing guidelines. Pre-operative staging was followed by 1 year of follow-up. Outcomes are expressed in the percentage of correctly staged patients and the associated costs. The cost price of PET varied between and euro;736 and and euro;1,588 depending on the (hospital) setting and the procurement of 18FDG commercially or from on-site production. In the CWU group, 41% of the patients underwent a futile thoracotomy, whereas in the PET group 21% of the thoracotomies were considered futile (P=0.003). The average costs per patient in the CWU group were and euro;9,573 and in the PET group, and euro;8,284. The major cost driver was the number of hospital days related to recovery from surgery. Sensitivity analysis on the cost and accuracy of PET showed that the results were robust, i.e. in favour of the PET group. The addition of PET to CWU prevented futile surgery in one out of five patients with suspected NSCLC. Despite the additional PET costs, the total costs were lower in the PET group, mainly due to a reduction in the number of futile operations. The additional use of PET in the staging of patients with NSCLC is feasible, safe and cost saving from a clinical and from an economic perspective. (orig.)

  6. Cell-on-hydrogel platform made of agar and alginate for rapid, low-cost, multidimensional test of antimicrobial susceptibility.

    Science.gov (United States)

    Sun, Han; Liu, Zhengzhi; Hu, Chong; Ren, Kangning

    2016-08-01

    Antimicrobial resistance (AMR) is a rapidly increasing threat to the effective treatment of infectious diseases worldwide. The two major remedies include: (1) using narrow-spectrum antibiotics based on rapid diagnosis; and (2) developing new antibiotics. A key part of both remedies is the antimicrobial susceptibility test (AST). However, the current standard ASTs that monitor colony formation are costly and time-consuming and the new strategies proposed are not yet practical to be implemented. Herein, we report a strategy to fabricate whole-hydrogel microfluidic chips using alginate-doped agar. This agar-based microfabrication makes it possible to prepare inexpensive hydrogel devices, and allows a seamless link between microfluidics and conventional agar-based cell culture. Different from common microfluidic systems, in our system the cells are cultured on top of the device, similar to normal agar plate culture; on the other hand, the microfluidic channels inside the hydrogel allow precise generation of linear gradient of drugs, thus giving a better performance than the conventional disk diffusion method. Cells in this system are not exposed to any shear flow, which allows the reliable tracking of individual cells and AST results to be obtained within 2-3 hours. Furthermore, our system could test the synergistic effect of drugs through two-dimensional gradient generation. Finally, the platform could be directly implemented to new drug discovery and other applications wherein a fast, cost-efficient method for studying the response of microorganisms upon drug administration is desirable. PMID:27452345

  7. Conformational B-Cell Epitopes Prediction from Sequences Using Cost-Sensitive Ensemble Classifiers and Spatial Clustering

    Directory of Open Access Journals (Sweden)

    Jian Zhang

    2014-01-01

    Full Text Available B-cell epitopes are regions of the antigen surface which can be recognized by certain antibodies and elicit the immune response. Identification of epitopes for a given antigen chain finds vital applications in vaccine and drug research. Experimental prediction of B-cell epitopes is time-consuming and resource intensive, which may benefit from the computational approaches to identify B-cell epitopes. In this paper, a novel cost-sensitive ensemble algorithm is proposed for predicting the antigenic determinant residues and then a spatial clustering algorithm is adopted to identify the potential epitopes. Firstly, we explore various discriminative features from primary sequences. Secondly, cost-sensitive ensemble scheme is introduced to deal with imbalanced learning problem. Thirdly, we adopt spatial algorithm to tell which residues may potentially form the epitopes. Based on the strategies mentioned above, a new predictor, called CBEP (conformational B-cell epitopes prediction, is proposed in this study. CBEP achieves good prediction performance with the mean AUC scores (AUCs of 0.721 and 0.703 on two benchmark datasets (bound and unbound using the leave-one-out cross-validation (LOOCV. When compared with previous prediction tools, CBEP produces higher sensitivity and comparable specificity values. A web server named CBEP which implements the proposed method is available for academic use.

  8. Conformational B-cell epitopes prediction from sequences using cost-sensitive ensemble classifiers and spatial clustering.

    Science.gov (United States)

    Zhang, Jian; Zhao, Xiaowei; Sun, Pingping; Gao, Bo; Ma, Zhiqiang

    2014-01-01

    B-cell epitopes are regions of the antigen surface which can be recognized by certain antibodies and elicit the immune response. Identification of epitopes for a given antigen chain finds vital applications in vaccine and drug research. Experimental prediction of B-cell epitopes is time-consuming and resource intensive, which may benefit from the computational approaches to identify B-cell epitopes. In this paper, a novel cost-sensitive ensemble algorithm is proposed for predicting the antigenic determinant residues and then a spatial clustering algorithm is adopted to identify the potential epitopes. Firstly, we explore various discriminative features from primary sequences. Secondly, cost-sensitive ensemble scheme is introduced to deal with imbalanced learning problem. Thirdly, we adopt spatial algorithm to tell which residues may potentially form the epitopes. Based on the strategies mentioned above, a new predictor, called CBEP (conformational B-cell epitopes prediction), is proposed in this study. CBEP achieves good prediction performance with the mean AUC scores (AUCs) of 0.721 and 0.703 on two benchmark datasets (bound and unbound) using the leave-one-out cross-validation (LOOCV). When compared with previous prediction tools, CBEP produces higher sensitivity and comparable specificity values. A web server named CBEP which implements the proposed method is available for academic use. PMID:25045691

  9. Minimal residual disease in acute lymphoblastic leukemia.

    Science.gov (United States)

    Campana, Dario

    2009-01-01

    In patients with acute lymphoblastic leukemia (ALL), monitoring of minimal residual disease (MRD) offers a way to precisely assess early treatment response and detect relapse. Established methods to study MRD are flow cytometric detection of abnormal immunophenotypes, polymerase chain reaction (PCR) amplification of antigen-receptor genes, and PCR amplification of fusion transcripts. The strong correlation between MRD levels and risk of relapse in childhood ALL is well demonstrated; studies in adult patients also support its prognostic value. Hence, results of MRD studies can be used to select treatment intensity and duration, and to estimate the optimal timing for hematopoietic stem cell transplantation. Practical issues in the implementation of MRD assays in clinical studies include determining the most informative time point to study MRD and the levels of MRD that will trigger changes in treatment intensity, as well as the relative cost and informative power of different methodologies. The identification of new markers of leukemia and the use of increasingly refined assays should further facilitate routine monitoring of MRD and help to clarify the cellular and biologic features of leukemic cells that resist chemotherapy in vivo. PMID:19100372

  10. Practical approaches toward waste minimization

    International Nuclear Information System (INIS)

    In the last decade, hazardous waste management has become a national concern. As more and more contamination is attributed to past hazardous waste handling and disposal practices, government and industry are fuming toward alternative methods of dealing with hazardous waste. Clearly, traditional disposal methods will not solve the problem. For hazardous waste managers, proper management of their company's or client's waste has become increasingly complex, expensive and demanding. Companies are struggling to keep up and comply with emerging regulations. Land disposal costs are increasing, as are the restrictions for the types of acceptable waste for disposal. Alternative treatment technologies are difficult to permit and are often too expensive for small-quantity generators. Liability for hazardous waste practices has become a frightening issue, with cleanup costs ranging into the millions of dollars. Public image has become a growing concern for many companies, with public input and risk communication playing increasingly important roles in the hazardous waste arena. These problems of waste management are not easily solved. Many strategies are available for dealing with hazardous wastes, including waste minimization. To put waste minimization into perspective, the following section compares the advantages and disadvantages of different waste management strategies

  11. Cost-effectiveness of treating vascular leg ulcers with UrgoStart(®) and UrgoCell(®) Contact.

    Science.gov (United States)

    Augustin, Matthias; Herberger, Katharina; Kroeger, Knut; Muenter, Karl C; Goepel, Lisa; Rychlik, Reinhard

    2016-02-01

    Although chronic wounds have a high socio-economic impact, data on comparative effectiveness of treatments are rare. UrgoStart(®) is a hydroactive dressing containing a nano-oligosaccharide factor (NOSF). This study aimed at evaluating the cost-effectiveness of this NOSF-containing wound dressing in vascular leg ulcers compared with a similar neutral foam dressing (UrgoCell(®) Contact) without NOSF. Cost-effectiveness analysis from the perspective of the German statutory health care system was performed using a decision tree model for a period of 8 weeks. Cost and outcome data were derived from the clinical study 'Challenge' suggesting a response rate (≥40% wound size reduction) of UrgoStart(®) of 65·6% versus 39·4% for the comparator. In the treatment model, effect-adjusted costs of €849·86 were generated after 8 weeks for treatment with UrgoStart(®) versus €1335·51 for the comparator resulting in an effect-adjusted cost advantage of €485·64 for UrgoStart(®) . In linear sensitivity analyses, the outcomes were stable for varying assumptions on prices and response rates. In an 8-week period of treatment for vascular leg ulcers, UrgoStart(®) shows superior cost-effectiveness when compared with the similar neutral foam dressing without any active component (NOSF). As demonstrated within a randomised, double-blind clinical trial, UrgoStart(®) is also more effective in wound area reduction than the neutral foam dressing. Wound healing was not addressed in this clinical trial. Follow-up data of 12 months to allow for reulceration assessment were not generated. PMID:24618370

  12. Minimally Invasive Lumbar Discectomy

    Medline Plus

    Full Text Available ... possible incision to minimize the injury to the tissues, particularly the muscles, the skin, and the ligaments, ... easier, and it limits the damage to the tissues around. So it’s a much safer procedure for ...

  13. Minimally Invasive Lumbar Discectomy

    Medline Plus

    Full Text Available ... neurosurgeon going with that, or should patients be seeking out versed in the minimally invasive procedures? The ... right. 16 Okay. And the studies, do they support that, do they show that quicker recovery times, ...

  14. Ruled Laguerre minimal surfaces

    KAUST Repository

    Skopenkov, Mikhail

    2011-10-30

    A Laguerre minimal surface is an immersed surface in ℝ 3 being an extremal of the functional ∫ (H 2/K-1)dA. In the present paper, we prove that the only ruled Laguerre minimal surfaces are up to isometry the surfaces ℝ (φλ) = (Aφ, Bφ, Cφ + D cos 2φ) + λ(sin φ, cos φ, 0), where A,B,C,D ε ℝ are fixed. To achieve invariance under Laguerre transformations, we also derive all Laguerre minimal surfaces that are enveloped by a family of cones. The methodology is based on the isotropic model of Laguerre geometry. In this model a Laguerre minimal surface enveloped by a family of cones corresponds to a graph of a biharmonic function carrying a family of isotropic circles. We classify such functions by showing that the top view of the family of circles is a pencil. © 2011 Springer-Verlag.

  15. Minimally Invasive Lumbar Discectomy

    Medline Plus

    Full Text Available ... because obviously the surgeon is sort of the person that everybody focuses on. But minimally invasive surgery ... on a regular basis, you should sort of act like a baseball player in spring training. You ...

  16. Minimalism. Clip and Save.

    Science.gov (United States)

    Hubbard, Guy

    2002-01-01

    Provides background information on the art movement called "Minimalism" discussing why it started and its characteristics. Includes learning activities and information on the artist, Donald Judd. Includes a reproduction of one of his art works and discusses its content. (CMK)

  17. Minimally Invasive Lumbar Discectomy

    Medline Plus

    Full Text Available ... with the smallest possible incision to minimize the injury to the tissues, particularly the muscles, the skin, ... the world. It’s one of the most common injuries and one of the most common causes of ...

  18. Minimally Invasive Lumbar Discectomy

    Medline Plus

    Full Text Available ... minimize the injury to the tissues, particularly the muscles, the skin, and the ligaments, to get to ... But rather using their backs regularly so the muscles heal with normal movement. Now the traditional discectomy ...

  19. Minimally Invasive Lumbar Discectomy

    Medline Plus

    Full Text Available ... because obviously the surgeon is sort of the person that everybody focuses on. But minimally invasive surgery ... can do to safeguard. Probably the biggest risk factor, although we see plenty of these problems in ...

  20. Minimally Invasive Lumbar Discectomy

    Medline Plus

    Full Text Available ... approach. The word that we put in the operative record is minimal. We’re talking about maybe ... we’re looking at 20-times magnification. The operative area, the field that they’re working is ...

  1. The cost of virulence : retarded growth of Salmonella Typhimurium cells expressing type III secretion system 1

    NARCIS (Netherlands)

    Sturm, Alexander; Heinemann, Matthias; Arnoldini, Markus; Benecke, Arndt; Ackermann, Martin; Benz, Matthias; Dormann, Jasmine; Hardt, Wolf-Dietrich

    2011-01-01

    Virulence factors generally enhance a pathogen's fitness and thereby foster transmission. However, most studies of pathogen fitness have been performed by averaging the phenotypes over large populations. Here, we have analyzed the fitness costs of virulence factor expression by Salmonella enterica s

  2. Low Cost Ferritic Stainless Steel in Dye Sensitized Solar Cells with Cobalt Complex Electrolyte

    OpenAIRE

    Miettunen, Kati; Jouttijärvi, Sami; Jiang, Roger; Saukkonen, Tapio; Romu, Jyrki; Halme, Janne; Lund, Peter

    2014-01-01

    Cheap ferritic stainless steel is applied here as the counter electrode substrate in dye sensitized solar cells with cobalt complex electrolyte. A 5.0% efficiency was reached with these type of cells which is more than 2.5 times higher compared to previously reported devices with metal counter electrode and cobalt complex electrolyte. The electrochemical impedance spectra analysis showed that the best cells with the ferritic steel counter electrode had as low charge transfer resistance (3.6 Ω...

  3. Development towards 20% efficient n-type Si MWT solar cells for low-cost industrial production

    Energy Technology Data Exchange (ETDEWEB)

    Guillevin, N.; Heurtault, B.J.B.; Bennett, I.J.; Guichoux, M.G.; Geerligs, L.J.; Weeber, A.W. [ECN Solar Energy, P.O. Box 1, NL-1755 ZG Petten (Netherlands); Jingfeng, X.; Zhiyan, H.; Gaofei, L.; Wenchao, Z.; Yingle, C.; Jianming, W.; Ziqian, W.; Jianhui, C. [Yingli Solar, 3399 Chaoyang North Street, Boading (China)

    2011-09-15

    Low 'Euros per Watt-peak' and ease of industrialization are the main drivers towards successful introduction on the market. In this regard, back-contact solar cells on n-type silicon offer significant benefits. The efficiency of back-contact cells, such as Metal Wrap Through (MWT) cells, compared to the traditional H-pattern cells is higher at cell level, thanks to the reduced shading losses, and is higher at module level, thanks to the reduced interconnection resistance losses. N-type silicon benefits from improved electrical properties of n-type silicon compared to p-type (higher minority carrier diffusion lengths, lower sensitivity to many impurities). Furthermore, the availability of an industrial cell process designed by ECN, resulting in bifacial cells (good rear surface passivation and light trapping), makes n-type silicon a perfect candidate for high efficiency solar cells and requires only modest changes to the current wafer and cell production processes. In order to reduce processing costs and increase module efficiencies, we have started two years ago the development of the Metal-Wrap-Through (MWT) solar cell technology on n-type mono-crystalline silicon wafers. Within the last year, efficiency of our MWT silicon solar cells manufactured from n-type Cz silicon wafers has been improved by 1% absolute. Based on common industrial cell processing steps such as diffusion, screen-printing metallization and firing through, we have obtained efficiencies up to 19.7% (in-house measurements) on large area wafers (239 cm{sup 2}, 5 {omega}cm), with clear potential for further improvement. In this article, we present a first direct comparison experiment between n-type bifacial MWT and non back-contact n-type bifacial H-pattern technologies, in which an efficiency gain of 0.30% absolute for MWT cells is demonstrated. At the moment, series resistance and, as a result, fill factor are still sub-optimal. Nevertheless, with current density (Jsc) values

  4. Out of Minimalism

    OpenAIRE

    Hedlin Hayden, Malin

    2003-01-01

    The dissertation involves a threefold investigation of sculpture. Firstly, the interpretations are focused on particular artworks by three British sculptors: Antony Gormley (b. 1950), Anish Kapoor (b. 1954), and Rachel Whiteread (b. 1963), respectively. The notion of applied minimalism is tentatively applied to their sculptures. A primary argument is that these works are idiomatically, thematically, and theoretically founded on the heritage of American Minimalism from the 1960s. The sculpture...

  5. Minimalism at War

    OpenAIRE

    Sunstein, Cass Robert

    2004-01-01

    When national security conflicts with individual liberty, reviewing courts might adopt one of three general orientations: National Security Maximalism, Liberty Maximalism, and minimalism. National Security Maximalism calls for a great deal of deference to the President, above all because of his authority as Commander-in-Chief of the Armed Forces. Liberty Maximalism asks courts to assume the same liberty-protecting posture in times of war as in times of peace. Minimalism asks courts to follow ...

  6. Progress in N-type Si Solar Cell and Module Technology for High Efficiency and Low Cost

    Energy Technology Data Exchange (ETDEWEB)

    Song, Dengyuan; Xiong, Jingfeng; Hu, Zhiyan; Li, Gaofei; Wang, Hongfang; An, Haijiao; Yu, Bo; Grenko, Brian; Borden, Kevin; Sauer, Kenneth; Cui, Jianhua; Wang, Haitao [Yingli Green Energy Holding Co., LTD, 071051 Boading (China); Roessler, T. [Yingli Green Energy Europe GmbH, Heimeranstr. 37, 80339 Munich (Germany); Bultman, J. [ECN Solar Energy, P.O. Box 1, NL-1755 ZG Petten (Netherlands); Vlooswijk, A.H.G.; Venema, P.R. [Tempress Systems BV, Radeweg 31, 8171 Vaassen (Netherlands)

    2012-06-15

    A novel high efficiency solar cell and module technology, named PANDA, using crystalline n-type CZ Si wafers has moved into large-scale production at Yingli. The first commercial sales of the PANDA modules commenced in mid 2010. Up to 600MW of mass production capacity from crystal-Si growth, wafer slicing, cell processing and module assembly have been implemented by the end of 2011. The PANDA technology was developed specifically for high efficiency and low cost. In contrast to the existing n-type Si solar cell manufacturing methods in mass production, this new technology is largely compatible with a traditional p-type Si solar cell production line by conventional diffusion, SiNx coating and screen-printing technology. With optimizing all technologies, Yingli's PANDA solar cells on semi-square 6-inch n-type CZ wafers (cell size 239cm{sup 2}) have been improved to currently have an average efficiency on commercial production lines exceeding 19.0% and up to 20.0% in pilot production. The PANDA modules have been produced and were certified according to UL1703, IEC 61215 and IEC 61730 standards. Nearly two years of full production on scale-up lines show that the PANDA modules have a high efficiency and power density, superior high temperature performance, near zero initial light induced degradation, and excellent efficiency at low irradiance.

  7. Low-Cost Upscaling Compatibility of Five Different ITO-Free Architectures for Polymer Solar Cells

    DEFF Research Database (Denmark)

    Angmo, Dechan; Gonzalez-Valls, Irene; Veenstra, Sjoerd;

    2013-01-01

    Five different indium-tin-oxide free (ITO-free) polymer solar cell architectures provided by four participating research institutions that all presented a laboratory cell performance sufficient for use in mobile and information and communication technology (ICT) were evaluated based on photovolta...

  8. Cost-effective, transparent iron selenide nanoporous alloy counter electrode for bifacial dye-sensitized solar cell

    Science.gov (United States)

    Liu, Juan; Tang, Qunwei; He, Benlin; Yu, Liangmin

    2015-05-01

    Pursuit of cost-effective and efficient counter electrodes (CEs) is a persistent objective for dye-sensitized solar cells (DSSCs). We present here the design of transparent Fe-Se nanoporous alloy CEs for bifacial DSSC applications. Due to the superior charge-transfer ability for I-/I3- redox couples, electrocatalytic reduction toward I3- species, and optical transparency in visible-light region, the bifacial DSSC with FeSe alloy electrode yields maximum front and rear efficiencies of 9.16% and 5.38%, respectively. A fast start-up, high multiple start capability, and good stability of the FeSe alloy CE demonstrate the potential applications in driving solar panels. The impressive efficiency along with simple preparation of the cost-effective Fe-Se nanoporous alloy CEs highlights their potential application in robust bifacial DSSCs.

  9. Maintenance erlotinib in advanced nonsmall cell lung cancer: cost-effectiveness in EGFR wild-type across Europe

    Directory of Open Access Journals (Sweden)

    Walleser S

    2012-09-01

    Full Text Available Silke Walleser,1 Joshua Ray,2 Helge Bischoff,3 Alain Vergnenègre,4 Hubertus Rosery,5 Christos Chouaid,6 David Heigener,7 Javier de Castro Carpeño,8 Marcello Tiseo,9 Stefan Walzer21Health Economic Consultancy, Renens, Switzerland; 2F Hoffmann-La Roche Pharmaceuticals AG, Basel, Switzerland; 3Thoracic Hospital of Heidelberg, Heidelberg, Germany; 4Limoges University Hospital, Limoges, France; 5Assessment-in-Medicine GmbH, Loerrach, Germany; 6Hospital Saint Antoine, Paris, France; 7Hospital Grosshansdorf, Grosshansdorf, Germany; 8University Hospital La Paz, Madrid, Spain; 9University Hospital of Parma, Parma, ItalyBackground: First-line maintenance erlotinib in patients with locally advanced or metastatic nonsmall cell lung cancer (NSCLC has demonstrated significant overall survival and progression-free survival benefits compared with best supportive care plus placebo, irrespective of epidermal growth factor receptor (EGFR status (SATURN trial. The cost-effectiveness of first-line maintenance erlotinib in the overall SATURN population has been assessed and published recently, but analyses according to EGFR mutation status have not been performed yet, which was the rationale for assessing the cost-effectiveness of first-line maintenance erlotinib specifically in EGFR wild-type metastatic NSCLC.Methods: The incremental cost per life-year gained of first-line maintenance erlotinib compared with best supportive care in patients with EGFR wild-type stable metastatic NSCLC was assessed for five European countries (the United Kingdom, Germany, France, Spain, and Italy with an area-under-the-curve model consisting of three health states (progression-free survival, progressive disease, death. Log-logistic survival functions were fitted to Phase III patient-level data (SATURN to model progression-free survival and overall survival. The first-line maintenance erlotinib therapy cost (modeled for time to treatment cessation, medication cost in later lines, and

  10. The Super-Spinner: a low cost animal cell culture bioreactor for the CO 2 incubator

    OpenAIRE

    Heidemann, R; Riese, U.; Lütkemeyer, Dirk; Büntemeyer, Heino; Lehmann, Jürgen

    1994-01-01

    The production of small quantities of monoclonal antibodies and recombinant proteins was carried out using a new low cost production system, the Super Spinner. Into a 1 1 standard Duran(R) flask a membrane stirrer equipped with a polypropylene hollow fiber membrane was installed to improve the oxygen supply by bubble-free aeration. The aeration was facilitated by using the CO2 conditioned incubator gas, which was pumped through the membrane stirrer via a small membrane pump. The maximal oxyge...

  11. Status of n-type solar cells for low-cost industrial production

    Energy Technology Data Exchange (ETDEWEB)

    Weeber, A.W.; Naber, R.C.G.; Guillevin, N.; Barton, P.C.; Carr, A.J.; Oosterling - Saynova, D.S.; Burgers, A.R.; Geerligs, L.J. [ECN Solar Energy, Petten (Netherlands)

    2009-09-15

    We have reached 18.6% efficiency on large area (243 cm{sup 2}) n-type crystalline silicon solar cells using conventional industrial processes like tube furnace diffusion and screen-printing. The 18.6% cell is a bifacial one with a boron emitter at the front side and a phosphorous back-surface-field (BSF). We have applied an industrially feasible boron/phosphorous co-diffusion process, and a simple wet-chemical oxidation process to passivate the highly-doped boron emitter. In this paper we will compare our results to those obtained by others. Another cell type discussed in the paper is an n-type cell with the junction at the rear. This cell has a screen-printed aluminium alloyed emitter, and the processing is comparable to conventional p-type cells. We have obtained an efficiency of 17.4% with this n-type cell. Possible improvements discussed in literature are presented as well.

  12. Sacrificing power for more cost-effective treatment: A techno-economic approach for engineering microbial fuel cells.

    Science.gov (United States)

    Stoll, Zachary A; Ma, Zhaokun; Trivedi, Christopher B; Spear, John R; Xu, Pei

    2016-10-01

    Microbial fuel cells (MFCs) are a promising energy-positive wastewater treatment technology, however, the system's cost-effectiveness has been overlooked. In this study, two new anode materials - hard felt (HF) and carbon foam (CF) - were evaluated against the standard graphite brush (GB) to determine if using inexpensive materials with less than ideal properties can achieve more cost-effective treatment than high-cost, high-performing materials. Using domestic wastewater as the substrate, power densities for the GB, HF and CF-MFCs were 393, 339 and 291 mW m(-2) normalized by cathodic surface area, respectively. Higher power densities correlated with larger anodic surface areas and anodic current densities but not with electrical conductivity. Cyclic voltammetry revealed that redox systems used for extracellular electron transport in the GB, HF and CF-MFCs were similar (-0.143 ± 0.046, -0.158 ± 0.004 and -0.100 ± 0.014 V vs. Ag/AgCl) and that the electrochemical kinetics of the MFCs showed no correlation with their respective electrical conductivity. 16S rRNA sequencing showed the GB, HF and CF microbial community compositions were not statistically different while organic removal rates were nearly identical for all MFCs. The HF-MFC generated a power output to electrode cost (W $(-1)) 1.9 times greater than the GB-MFC, despite producing 14% less power and 15% less anodic current, while having 2.6 times less anodic surface area, 2.1 times larger charge transfer resistance and an electrical conductivity three orders of magnitude lower. The results demonstrate that inexpensive materials are capable of achieving more cost-effective treatment than high-performing materials despite generating lower power when treating real wastewater. PMID:27395791

  13. High Efficiency Solar Cell on Low Cost Metal Foil Substrate Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Future space missions will require Solar cell arrays having specific power ratings in excess of 1000 W/kg. Conventional crystalline photovoltaic technology...

  14. Small-Scale Low Cost Solid Oxide Fuel Cell Power Systems

    Energy Technology Data Exchange (ETDEWEB)

    S.D. Vora

    2005-09-30

    Tasks carried out during the reporting period March 2005-August 2005 are summarized. During this reporting period, the primary focus was on tasks leading to the fabrication of a proof-of-concept (POC) unit with HPD5R1 cells. Assembly of the POC unit was completed and the initial operation was started. Optimization of HPD cell design, investigation of scandia doped zirconia and low temperature operation of YSZ electrolyte based cells continued. Development of seal to be used in a ''once-thru'' design or an ''up-down'' design was started. Attachment 1 describes the progress in cell development and Attachments 2 and 3 deal with status of generator and BOP design. Operation of POC is summarized in Attachment 4. Plans for future work are summarized in Attachment 5.

  15. Recent developments on low-cost industrial processing of n-type silicon solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Weeber, A.W.; Burgers, A.R.; Guillevin, N.; Carr, A.J.; Barton, P.C.; Geerligs, L.J. [ECN Solar Energy, P.O. Box 1, NL-1755 ZG Petten (Netherlands); Jingfeng, Xiong; Gaofei, Li; Weipeng, Song; Haijiao, An; Zhiyan, Hu [Yingli Solar, 3399 Chaoyang North Street, Boading (China); Venema, P.R.; Vlooswijk, A.H.G. [Tempress Systems BV, Radeweg 31, 8171 Vaassen (Netherlands)

    2010-11-15

    We present the status of our process development of n-type silicon solar cells, and progress towards its industrial implementation. For cells with a so-called H-pattern front side metallization independently confirmed efficiencies for Cz wafers of 18.65% (239 cm{sup 2}) have been obtained, and since then, cells have already shown further improvement to more than 19%. To our knowledge these are the highest stable efficiencies obtained with industrial processing on 6 inch n-type wafers. We present an update of our process development, including efficiency improvements, transfer to 6 inch size, and key features of the current bifacial cells with H-pattern metallization. Results are illustrated with data from Yingli PANDA pilot production.

  16. Waste minimization assessment procedure

    International Nuclear Information System (INIS)

    Perry Nuclear Power Plant began developing a waste minimization plan early in 1991. In March of 1991 the plan was documented following a similar format to that described in the EPA Waste Minimization Opportunity Assessment Manual. Initial implementation involved obtaining management's commitment to support a waste minimization effort. The primary assessment goal was to identify all hazardous waste streams and to evaluate those streams for minimization opportunities. As implementation of the plan proceeded, non-hazardous waste streams routinely generated in large volumes were also evaluated for minimization opportunities. The next step included collection of process and facility data which would be useful in helping the facility accomplish its assessment goals. This paper describes the resources that were used and which were most valuable in identifying both the hazardous and non-hazardous waste streams that existed on site. For each material identified as a waste stream, additional information regarding the materials use, manufacturer, EPA hazardous waste number and DOT hazard class was also gathered. Once waste streams were evaluated for potential source reduction, recycling, re-use, re-sale, or burning for heat recovery, with disposal as the last viable alternative

  17. Rapid and Cost-Effective Gene Targeting in Rat Embryonic Stem Cells by TALENs

    OpenAIRE

    Tong, Chang; Huang, Guanyi; Ashton, Charles; WU, HONGPING; Yan, Hexin; Ying, Qi-Long

    2012-01-01

    The rat is the preferred animal model in many areas of biomedical research and drug development. Genetic manipulation in rats has lagged behind that in mice due to the lack of efficient gene targeting tools. Previously, we generated a knockout rat via conventional homologous recombination in rat embryonic stem (ES) cells. Here, we show that efficient gene targeting in rat ES cells can be achieved quickly through transcription activator-like effector nuclease (TALEN)-mediated DNA double-strand...

  18. Minimal gaugino mediation

    International Nuclear Information System (INIS)

    We propose minimal gaugino mediation as the simplest known solution to the supersymmetric flavor and CP problems. The framework predicts a very minimal structure for the soft parameters at ultrahigh energies: gaugino masses are unified and non-vanishing whereas all other soft supersymmetry breaking parameters vanish. We show that this boundary condition naturally arises from a small extra dimension and present a complete model which includes a new extra-dimensional solution to the μ problem. We briefly discuss the predicted superpartner spectrum as a function of the two parameters of the model. The commonly ignored renormalization group evolution above the GUT scale is crucial to the viability of minimal gaugino mediation but does not introduce new model dependence

  19. Minimal Gaugino Mediation

    International Nuclear Information System (INIS)

    The authors propose Minimal Gaugino Mediation as the simplest known solution to the supersymmetric flavor and CP problems. The framework predicts a very minimal structure for the soft parameters at ultra-high energies: gaugino masses are unified and non-vanishing whereas all other soft supersymmetry breaking parameters vanish. The authors show that this boundary condition naturally arises from a small extra dimension and present a complete model which includes a new extra-dimensional solution to the mu problem. The authors briefly discuss the predicted superpartner spectrum as a function of the two parameters of the model. The commonly ignored renormalization group evolution above the GUT scale is crucial to the viability of Minimal Gaugino Mediation but does not introduce new model dependence

  20. Wet-process Fabrication of Low-cost All-solid Wire-shaped Solar Cells on Manganese-plated Electrodes

    International Nuclear Information System (INIS)

    Highlights: • All-solid wire-shaped flexible solar cells are firstly assembled on low-cost Mn-plated fibers. • Energy efficiency improved by >27% after coating a layer of Mn on various substrates. • The cell is fabricated via wet process under low temperature and mild pH conditions. • Stable flexible solar cells are realized on lightweight and low-cost polymer fiber. - Abstract: All-solid wire-shaped flexible solar cells are assembled for the first time on low-cost Mn-plated wires through wet-process fabrication under low temperature and mild pH conditions. With a price cheap as the steel, metal Mn can be easily plated on almost any substrates, and evidently promote the photovoltaic efficiency of wire-shaped solar cells on various traditional metal wire substrates, such as Fe and Ti, by 27% and 65%, respectively. Flexible solar cell with much lower cost and weight is assembled on Mn-plated polymer substrate, and is still capable of giving better performance than that on Fe or Ti substrate. Both its mechanical and chemical stability are good for future weaving applications. Owing to the wire-type structure, such low-cost metals as Mn, which are traditionally regarded as unsuitable for solar cells, may provide new opportunities for highly efficient solar cells

  1. Minimal Genus One Curves

    OpenAIRE

    Sadek, Mohammad

    2010-01-01

    In this paper we consider genus one equations of degree $n$, namely a (generalised) binary quartic when $n=2$, a ternary cubic when $n=3$, and a pair of quaternary quadrics when $n=4$. A new definition for the minimality of genus one equations of degree $n$ over local fields is introduced. The advantage of this definition is that it does not depend on invariant theory of genus one curves. We prove that this definition coincides with the classical definition of minimality for all $n\\le4$. As a...

  2. Minimalism and Speakers’ Intuitions

    Directory of Open Access Journals (Sweden)

    Matías Gariazzo

    2011-08-01

    Full Text Available Minimalism proposes a semantics that does not account for speakers’ intuitions about the truth conditions of a range of sentences or utterances. Thus, a challenge for this view is to offer an explanation of how its assignment of semantic contents to these sentences is grounded in their use. Such an account was mainly offered by Soames, but also suggested by Cappelen and Lepore. The article criticizes this explanation by presenting four kinds of counterexamples to it, and arrives at the conclusion that minimalism has not successfully answered the above-mentioned challenge.

  3. A 3D paper-based enzymatic fuel cell for self-powered, low-cost glucose monitoring.

    Science.gov (United States)

    Fischer, Christopher; Fraiwan, Arwa; Choi, Seokheun

    2016-05-15

    In this work, we demonstrate a novel low-cost, self-powered paper-based biosensor for glucose monitoring. The device operating mechanism is based on a glucose/oxygen enzymatic fuel cell using an electrochemical energy conversion as a transducing element for glucose monitoring. The self-powered glucose biosensor features (i) a 3D origami paper-based structure for easy system integration onto paper, (ii) an air-cathode on paper for low-cost production and easy operation, and (iii) a screen printed chitosan/glucose oxidase anode for stable current generation as an analytical signal for glucose monitoring. The sensor showed a linear range of output current at 1-5mM glucose (R(2)=0.996) with a sensitivity of 0.02 µA mM(-1). The advantages offered by such a device, including a low cost, lack of external power sources/sophisticated external transducers, and the capacity to rapidly generate reliable results, are well suited for the clinical and social settings of the developing world. PMID:26706941

  4. The Cost of Privacy: Riley v. California's Impact on Cell Phone Searches

    Directory of Open Access Journals (Sweden)

    Jennifer Moore

    2014-09-01

    Full Text Available Riley v. California is the United States Supreme Court’s first attempt to regulate the searches of cell phones by law enforcement.  The 2014 unanimous decision requires a warrant for all cell phone searches incident to arrest absent an emergency.  This work summarizes the legal precedent and analyzes the limitations and practical implications of the ruling.  General guidelines for members of the criminal justice system at all levels consistent with the Supreme Court’s decision are provided.  

  5. Peanut shaped ZnO microstructures: controlled synthesis and nucleation growth toward low-cost dye sensitized solar cells

    Science.gov (United States)

    Prabhu, M.; Mayandi, J.; Mariammal, R. N.; Vishnukanthan, V.; Pearce, J. M.; Soundararajan, N.; Ramachandran, K.

    2015-06-01

    This paper describes a simple, low-temperature and cost effective chemical precipitation method in aqueous media to synthesis uniformly distributed zinc oxide (ZnO) microstructures for the fabrication of dye-sensitized solar cells (DSSCs). The size and morphology of the ZnO microstructures are systematically controlled by adjusting the concentration of the precursors, zinc acetate dihydrate and ammonium hydroxide. X-ray diffraction (XRD) and scanning electron microscopy are used for the structural characterizations and photoluminescence and Fourier transform infrared spectroscopy are used to characterize the optical properties of the ZnO, respectively. The results reveal that ZnO crystallites exhibit hexagonal wurtzite structure with preferential orientation along c-axis. The effect of ammonia concentration on the crystallinity, morphology and optical properties of ZnO microstructures and the concomitant effect on the efficiency of DSSCs is also quantified. The peanut-shaped ZnO microstructure, which was found to increase DSSCs performance over other microstructure, is studied in detail in order to develop a formation mechanism. A sandwich type eosin yellow sensitized solar cell is prepared using peanut-shaped ZnO microstructures, which showed an efficiency of 0.37%. Ammonia was found to play a crucial role in the evolution of ZnO morphologies. These results are promising and provide a path towards low-cost high-performance DSSCs based on peanut-shaped ZnO microstructures and produced with only relatively simple wet chemistry synthesis.

  6. Minimally Invasive Lumbar Discectomy

    Medline Plus

    Full Text Available ... called a “minimally invasive microscopic lumbar discectomy.” Now this is a patient who a 46-year-old ... L-5, S-1. So that’s why she’s having this procedure. The man who is doing the procedure ...

  7. Minimally Invasive Lumbar Discectomy

    Medline Plus

    Full Text Available ... part of the sciatic nerve. You know one good important thing to talk about is the concept of “I ... in the minimally invasive procedures? The most important thing is to have a good trusting relationship between your surgeon and yourself, and ...

  8. Minimally Invasive Stomas

    OpenAIRE

    Hellinger, Michael D.; Al Haddad, Abdullah

    2008-01-01

    Traditionally, stoma creation and end stoma reversal have been performed via a laparotomy incision. However, in many situations, stoma construction may be safely performed in a minimally invasive nature. This may include a trephine, laparoscopic, or combined approach. Furthermore, Hartmann's colostomy reversal, a procedure traditionally associated with substantial morbidity, may also be performed laparoscopically. The authors briefly review patient selection, preparation, and indications, and...

  9. Hazardous waste minimization

    International Nuclear Information System (INIS)

    This book presents an overview of waste minimization. Covers applications of technology to waste reduction, techniques for implementing programs, incorporation of programs into R and D, strategies for private industry and the public sector, and case studies of programs already in effect

  10. Minimal DBM Substraction

    DEFF Research Database (Denmark)

    David, Alexandre; Håkansson, John; G. Larsen, Kim; Pettersson, Paul

    In this paper we present an algorithm to compute DBM substractions with a guaranteed minimal number of splits and disjoint DBMs to avoid any redundance. The substraction is one of the few operations that result in a non-convex zone, and thus, requires splitting. It is of prime importance to reduce...

  11. Minimal Walking Technicolor

    DEFF Research Database (Denmark)

    Frandsen, Mads Toudal

    2007-01-01

    I report on our construction and analysis of the effective low energy Lagrangian for the Minimal Walking Technicolor (MWT) model. The parameters of the effective Lagrangian are constrained by imposing modified Weinberg sum rules and by imposing a value for the S parameter estimated from the...

  12. Minimally Invasive Lumbar Discectomy

    Medline Plus

    Full Text Available ... Miami’s Baptist Hospital. You’re going to be a seeing a procedure called a “minimally invasive microscopic lumbar discectomy.” Now this is a patient who a 46-year-old woman who ...

  13. Logarithmic Superconformal Minimal Models

    CERN Document Server

    Pearce, Paul A; Tartaglia, Elena

    2013-01-01

    The higher fusion level logarithmic minimal models LM(P,P';n) have recently been constructed as the diagonal GKO cosets (A_1^{(1)})_k oplus (A_1^{(1)})_n / (A_1^{(1)})_{k+n} where n>0 is an integer fusion level and k=nP/(P'-P)-2 is a fractional level. For n=1, these are the logarithmic minimal models LM(P,P'). For n>1, we argue that these critical theories are realized on the lattice by n x n fusion of the n=1 models. For n=2, we call them logarithmic superconformal minimal models LSM(p,p') where P=|2p-p'|, P'=p' and p,p' are coprime, and they share the central charges of the rational superconformal minimal models SM(P,P'). Their mathematical description entails the fused planar Temperley-Lieb algebra which is a spin-1 BMW tangle algebra with loop fugacity beta_2=x^2+1+x^{-2} and twist omega=x^4 where x=e^{i(p'-p)pi/p'}. Examples are superconformal dense polymers LSM(2,3) with c=-5/2, beta_2=0 and superconformal percolation LSM(3,4) with c=0, beta_2=1. We calculate the free energies analytically. By numerical...

  14. Mechanical properties of mammalian single smooth muscle cells. I. A low cost large range microforce transducer.

    NARCIS (Netherlands)

    J.J. Glerum (Jacobus); R. van Mastrigt (Ron)

    1990-01-01

    textabstractA transducer has been developed for measuring the minute forces generated during isometric contractions (1.0-10.0 microN) of single smooth muscle cells from the pig urinary bladder and the human uterus. In addition to its high sensitivity, resolution and stability (100 mV microN-1, and l

  15. Low-cost piezoresistive silicon load cell independent of force distribution

    NARCIS (Netherlands)

    Zwijze, Robert A.F.; Wiegerink, Remco J.; Krijnen, Gijs J.M.; Lammerink, Theo S.J.; Elwenspoek, Miko

    1999-01-01

    A silicon load cell (force sensor) is presented which is based on a new operating principle. The force is measured by compressing a meander like strain gage. A second strain gage which is not loaded, is used for temperature compensation and for compensation of bending and stretching stresses in the

  16. Low-cost piezoresistive silicon load cell independent of force ditribution

    NARCIS (Netherlands)

    Zwijze, Robert A.F.; Wiegerink, Remco J.; Krijnen, Gijs J.M.; Lammerink, Theo S.J.; Elwenspoek, Miko

    2000-01-01

    A silicon load cell (force sensor) that is based on a new operating principle is presented. The force is measured by compressing a meander-like strain gage. A second strain gage, which is not loaded, is used for temperature compensation and for compensation of bending and stretching stresses in the

  17. Low-cost plasmonic solar cells prepared by chemical spray pyrolysis

    Directory of Open Access Journals (Sweden)

    Erki Kärber

    2014-12-01

    Full Text Available Solar cells consisting of an extremely thin In2S3/CuInS2 buffer/absorber layer uniformly covering planar ZnO were prepared entirely by chemical spray pyrolysis. Au nanoparticles (Au-NPs were formed via thermal decomposition of a gold(III chloride trihydrate (HAuCl4·3H2O precursor by spraying 2 mmol/L of the aqueous precursor solution onto a substrate held at 260 °C. Current–voltage scans and external quantum efficiency spectra were used to evaluate the solar cell performance. This work investigates the effect of the location of the Au-NP layer deposition (front side vs rear side in the solar cell and the effect of varying the volume (2.5–10 mL of the sprayed Au precursor solution. A 63% increase (from 4.6 to 7.5 mA/cm2 of the short-circuit current density was observed when 2.5 mL of the precursor solution was deposited onto the rear side of the solar cell.

  18. A Total Cost of Ownership Model for Low Temperature PEM Fuel Cells in Combined Heat and Power and Backup Power Applications

    Energy Technology Data Exchange (ETDEWEB)

    University of California, Berkeley; Wei, Max; Lipman, Timothy; Mayyas, Ahmad; Chien, Joshua; Chan, Shuk Han; Gosselin, David; Breunig, Hanna; Stadler, Michael; McKone, Thomas; Beattie, Paul; Chong, Patricia; Colella, Whitney; James, Brian

    2014-06-23

    A total cost of ownership model is described for low temperature proton exchange membrane stationary fuel cell systems for combined heat and power (CHP) applications from 1-250kW and backup power applications from 1-50kW. System designs and functional specifications for these two applications were developed across the range of system power levels. Bottom-up cost estimates were made for balance of plant costs, and detailed direct cost estimates for key fuel cell stack components were derived using design-for-manufacturing-and-assembly techniques. The development of high throughput, automated processes achieving high yield are projected to reduce the cost for fuel cell stacks to the $300/kW level at an annual production volume of 100 MW. Several promising combinations of building types and geographical location in the U.S. were identified for installation of fuel cell CHP systems based on the LBNL modelling tool DER CAM. Life-cycle modelling and externality assessment were done for hotels and hospitals. Reduced electricity demand charges, heating credits and carbon credits can reduce the effective cost of electricity ($/kWhe) by 26-44percent in locations such as Minneapolis, where high carbon intensity electricity from the grid is displaces by a fuel cell system operating on reformate fuel. This project extends the scope of existing cost studies to include externalities and ancillary financial benefits and thus provides a more comprehensive picture of fuel cell system benefits, consistent with a policy and incentive environment that increasingly values these ancillary benefits. The project provides a critical, new modelling capacity and should aid a broad range of policy makers in assessing the integrated costs and benefits of fuel cell systems versus other distributed generation technologies.

  19. Spatial ALD Al2O3 film integrated in low-cost, high-performance bifacial solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Vermont, P.; Granneman, E.; Ernst, M.A. [Levitech BV, Versterkerstraat 10, 1322 AP, Almere (Netherlands); Cesar, I.; Mewe, A.A.; Weeber, A.W. [ECN Solar Energy, Petten (Netherlands)

    2012-09-15

    ALD (Atomic Layer Deposition) Al2O3 films have been integrated in an open rear-side p-PASHA (Passivated All Sides and H-pattern) type solar cell. The manufacturing of this cell is cost-effective as it uses a single dielectric Al2O3 layer (i.e. no SiNx capping layer), partial (30-50%) coverage of metal paste on the rear side, no laser opening or laser firing required, and co-firing of the Ag and Al pastes. The spatial ALD deposition is carried out in the Levitrack system which is characterized by a high throughput (up to 3600 wafers/hr) and strict separation of H2O and TMA compounds (tetramethacrylate) in the system. The Al2O3 film was thin enough to allow effective firing through, while avoiding the formation of defects (blisters) upon high-temperature firing. On p-type Cz and multi-crystalline material, the p-PASHA cell was superior to the reference full-BSF (back surface field) cell in J{sub sc} x V{sub oc} by 1% and 2.5% respectively. Local IQE (Iterative Query Expansion) mapping indicates that the Al2O3 passivation performance is maintained after firing.

  20. Production of "Green Natural Gas" Using Solid Oxide Electrolysis Cells (SOEC): Status of Technology and Costs

    DEFF Research Database (Denmark)

    Mogensen, Mogens Bjerg; Jensen, Søren Højgaard; Ebbesen, Sune Dalgaard; Hauch, Anne; Graves, Christopher R.; Høgh, Jens Valdemar Thorvald; Sun, Xiufu; Das, Shital; Hendriksen, Peter Vang; Nielsen, Jens U.; Pedersen, Aksel H.; Christiansen, Niels; Hansen, John B.

    2012-01-01

    This paper gives arguments in favour of using green natural gas (GNG) as storage media for the intermittent renewable energy sources. GNG is here defined as being CH4, i.e. methane, often called synthetic natural gas or substitute natural gas (SNG), produced using renewable or at least CO2 neutral...... energy sources only. Also dimethyl ether (DME = (CH3)2O), which might be called Liquefied Green Gas, LGG, in analogy to Liquefied Petroleum Gas, LPG, because DME has properties similar to LPG. It further gives a short review of the state of the art of electrolysis in general and SOEC in particular....... Production of synthesis gas (H2 + CO) from CO2 and H2O using SOEC technology is evaluated. GNG and LGG can be produced from synthesis gas (or short: syngas) by means of well established commercially available catalysis technology. Finally, estimations of costs and efficiencies are presented and the relative...

  1. Digital standard cells and operational amplifiers for operation up to 250 degrees C using low-cost CMOS technology

    Science.gov (United States)

    Stemmer, Jens; Ackermann, Joerg; Uffmann, Dirk; Aderhold, Jochen

    1996-09-01

    There is an increasing demand from automotive, aircraft and space industry for reliable high temperature resistant electronics. Circuits with reliable functionality up to temperatures of 250 degree(s)C would be sufficient for most of these applications. Digital standard cells and operational amplifiers are the basic building blocks of these circuits. Commercially available digital standard cell libraries and operational amplifiers are normally specified for operation up to a maximum temperature of 125 degree(s)C. Hence, the purpose of this work was the design and characterization of digital standard cells and operational amplifiers for operation up to 250 degree(s)C using a low-cost 1.0 micrometers epi-CMOS process. Several design measures were applied to the cells in order to further improve latch-up resistivity and to limit leakage currents, respectively. The transfer curves of all digital cells for all input signal combinations have been recorded in the temperature range from 30 to 250 degree(s)C. Significant results are very low temperature shifts of the noise margins and of the switching point, respectively. Furthermore, the low (0 V) and high (5 V) levels are reached exactly over the entire temperature range. Outstanding characteristics of the operational amplifier comprise low open-loop gain temperature drift as well as low offset and offset temperature drift, respectively. The open-loop gain was greater than 83 dB at room temperature with a drift of less than 0.02 dB/ degree(s)C. The offset voltage amounted to -1 mV at room temperature and 1 mV at 250 degree(s)C, respectively. The long-term behavior of these cells is currently under investigation.

  2. Solar cells with low cost substrates, process of making same and article of manufacture

    Science.gov (United States)

    Mitchell, K.W.

    A solar cell is disclosed having a substrate and an intermediate recrystallized film and a semiconductor material capable of absorbing light with the substrate being selected from one of a synthetic organic resin, graphite, glass and a crystalline material having a grain size less than about 1 micron/sup 2/. The intermediate recrystallized film has a grain size in the range of from about 10 microns/sup 2/ to about 10,000 microns/sup 2/ and a lattice mismatch with the semiconductor material not greater than about 4%. The semiconductor material has a grain size not less than about 10 microns/sup 2/. An anti-reflective layer and electrical contact means are provided. Also disclosed is a subcombination of substrate, intermediate recrystallized film and semiconductor material. Also, methods of formulating the solar cell and subcombination are disclosed.

  3. Graphene–sponges as high-performance low-cost anodes for microbial fuel cells

    KAUST Repository

    Xie, Xing

    2012-01-01

    A high-performance microbial fuel cell (MFC) anode was constructed from inexpensive materials. Key components were a graphene-sponge (G-S) composite and a stainless-steel (SS) current collector. Anode fabrication is simple, scalable, and environmentally friendly, with low energy inputs. The SS current collector improved electrode conductivity and decreased voltage drop and power loss. The resulting G-S-SS composite electrode appears promising for large-scale applications. © 2012 The Royal Society of Chemistry.

  4. Photostability of low cost dye-sensitized solar cells based on natural and synthetic dyes

    Science.gov (United States)

    Abdou, E. M.; Hafez, H. S.; Bakir, E.; Abdel-Mottaleb, M. S. A.

    2013-11-01

    This paper deals with the use of some natural pigments as well as synthetic dyes to act as sensitizers in dye-sensitized solar cells (DSSCs). Anthocyanin dye extracted from rosella (Hibiscus sabdariffa L.) flowers, the commercially available textile dye Remazole Red RB-133 (RR) and merocyanin-like dye based on 7-methyl coumarin are tested. The photostability of the three dyes is investigated under UV-Vis light exposure. The results show a relatively high stability of the three dyes. Moreover, the photostability of the solid dyes is studied over the TiO2 film electrodes. A very low decolorization rates are recorded as; rate constants k = 1.6, 2.1 and 1.9 × 10-3 min-1 for anthocyanin, RR and coumarin dyes, respectively. The stability results favor selecting anthocyanin as a promising sensitizer candidate in DSSCs based on natural products. Dyes-sensitized solar cells are fabricated and their conversion efficiency (η) is 0.27%, 0.14% and 0.001% for the anthocyanin, RR and coumarin dyes, respectively. Moreover, stability tests of the sealed cells based on anthocyanin and RR dyes are done under continuous light exposure of 100 mW cm-2, reveals highly stable DSSCs.

  5. Dye-sensitized solar cells based on low cost carbon-coated tungsten disulphide counter electrodes

    International Nuclear Information System (INIS)

    Highlights: •Carbon-coated WS2 films are used as the counter electrode in dye-sensitized solar cells. •The plastic carbon-coated WS2 counter electrodes are prepared at room temperature. •The device with carbon-coated WS2 electrode exhibits comparable performance to that of the cell with Pt electrode. -- Abstract: Carbon-coated tungsten disulphide (WS2) is synthesized using a simple method and characterized with X-ray diffraction, field emission scanning electron microscopy and laser Raman spectrum. The WS2-based counter electrodes for dye-sensitized solar cells (DSSCs) are prepared at low temperature. The electrochemical catalytic activity of the WS2 counter electrodes is investigated using cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The DSSCs assembled with carbon-coated WS2 counter electrodes show a photovoltaic conversion efficiency of 5.5%, which is comparable to that of the DSSCs based on Pt electrode (5.6%). Plastic WS2 counter electrodes are also prepared which give a photovoltaic conversion efficiency of 5.0%. Our study indicates that carbon-coated WS2 is a good candidate to replace the Pt counter electrodes in DSSCs

  6. Minimally Invasive Lumbar Discectomy

    Medline Plus

    Full Text Available ... on the type of job that the work environment, they can go to work right after I ... that, do they show that quicker recovery times, cost effectiveness, and is this covered by insurance? Oh, ...

  7. STRONGLY MINIMAL g* -CONTINUOUS MAPS AND STRONGLY MINIMAL g** -CONTINUOUS MAPS IN MINIMAL SPACES

    OpenAIRE

    E.Subha,; A.Pushpalatha

    2010-01-01

    In this paper, we introduce and study the concepts of a new class of maps, namely strongly minimal continuous maps, strongly minimal g*-continuous maps, strongly minimal g**-continuous maps which includes the class of continuous maps.

  8. The Minimal R$\

    CERN Document Server

    Cai, Yi

    2016-01-01

    Incorporating neutrino mass generation and a dark matter candidate in a unified model has always been intriguing. We present the minimal model to realize the dual-task procedure based on the one-loop ultraviolet completion of the Weinberg operator, in the framework of minimal dark matter and radiative neutrino mass generation. In addition to the Standard Model particles, the model consists of a real scalar quintuplet, a pair of vector-like quadruplet fermions and a fermionic quintuplet. The neutral component of the fermionic quintuplet serves as a good dark matter candidate which can be tested by the future direct and indirect detection experiments. The constraints from flavor physics and electroweak-scale naturalness are also discussed.

  9. Minimalism and speakers’ intuitions

    OpenAIRE

    Matías Gariazzo

    2012-01-01

    Minimalism proposes a semantics that does not account for speakers’ intuitions about the truth conditions of a range of sentences or utterances. Thus, a challenge for this view is to offer an explanation of how its assignment of semantic contents to these sentences is grounded in their use. Such an account was mainly offered by Soames, but also suggested by Cappelen and Lepore. The article criticizes this explanation by presenting four kinds of counterexamples to it, and arrives at the conclu...

  10. Minimally Invasive Thoracic Surgery

    OpenAIRE

    McFadden, P. Michael

    2000-01-01

    To reduce the risk, trauma, and expense of intrathoracic surgical treatments, minimally invasive procedures performed with the assistance of fiberoptic video technology have been developed for thoracic and bronchial surgeries. The surgical treatment of nearly every intrathoracic condition can benefit from a video-assisted approach performed through a few small incisions. Video-assisted thoracoscopic and rigid-bronchoscopic surgery have improved the results of thoracic procedures by decreasing...

  11. Minimal Composite Inflation

    DEFF Research Database (Denmark)

    Channuie, Phongpichit; Jark Joergensen, Jakob; Sannino, Francesco

    2011-01-01

    We investigate models in which the inflaton emerges as a composite field of a four dimensional, strongly interacting and nonsupersymmetric gauge theory featuring purely fermionic matter. We show that it is possible to obtain successful inflation via non-minimal coupling to gravity, and that the...... underlying dynamics is preferred to be near conformal. We discover that the compositeness scale of inflation is of the order of the grand unified energy scale....

  12. Improving Connectionist Energy Minimization

    OpenAIRE

    Pinkas, G.; Dechter, R

    1995-01-01

    Symmetric networks designed for energy minimization such as Boltzman machines and Hopfield nets are frequently investigated for use in optimization, constraint satisfaction and approximation of NP-hard problems. Nevertheless, finding a global solution (i.e., a global minimum for the energy function) is not guaranteed and even a local solution may take an exponential number of steps. We propose an improvement to the standard local activation function used for such networks. The improved algori...

  13. Low-cost piezoresistive silicon load cell independent of force distribution

    OpenAIRE

    Zwijze, Robert A.F.; Remco J. Wiegerink; Krijnen, Gijs J.M.; Lammerink, Theo S.J.; Elwenspoek, Miko

    1999-01-01

    A silicon load cell (force sensor) is presented which is based on a new operating principle. The force is measured by compressing a meander like strain gage. A second strain gage which is not loaded, is used for temperature compensation and for compensation of bending and stretching stresses in the chip. Also, same changes in zero load resistor values are eliminated. It is shown that the output of the bridge is a linear function of the total force and independent of the force distribution on ...

  14. Minimally entangled typical thermal state algorithms

    International Nuclear Information System (INIS)

    We discuss a method based on sampling minimally entangled typical thermal states (METTS) that can simulate finite temperature quantum systems with a computational cost comparable to the ground state density matrix renormalization group (DMRG). Detailed implementation of each step of the method is presented, along with efficient algorithms for working with matrix product states and matrix product operators. Furthermore, we explore how the properties of METTS can reveal characteristic order and excitations of systems and discuss why METTS form an efficient basis for sampling. Finally, we explore the extent to which the average entanglement of a METTS ensemble is minimal.

  15. Astaxanthinogenesis in the yeast Phaffia rhodozyma - optimization of low-cost culture media and yeast cell-wall lysis

    Energy Technology Data Exchange (ETDEWEB)

    Fontana, J.D.; Baron, M.; Guimaraes, M.F. [LQBB-Biomass Chemo Biotechnology Lab., Curitiba (Brazil)] [and others

    1997-12-31

    Astaxanthin is a diketo-dihydroxy-carotenoid produced by Phaffia rhodozyma, a basidiomicetous yeast. A low-cost fermentation medium consisting of raw sugarcane juice and urea was developed to exploit the active sucrolytic/urelolytic enzyme apparatus inherent to the yeast. As compared to the beneficial effect of 0.1 g% urea, a ready nitrogen source, mild phosphoric pre inversion of juice sucrose to glucose and fructose, promptly fermentable carbon sources, resulted in smaller benefits. Corn steep liquor (CSL) was found to be a valuable supplement for both yeast biomass yield (9.2 g dry cells/L) and astaxanthin production (1.3 mg/g cells). Distillery effluent (vinace), despite only a slightly positive effect on yeast growth, allowed for the highest pigment productivity (1.9 mg/g cells). Trace amounts of Ni{sup 2} (1 mg/L, as a cofactor for urease) resulted in controversial effects, namely, biomass decrease and astaxanthin increase, with no effect on the release (and uptake) of ammonium ion from urea. 13 refs., 6 figs.

  16. Minimal Disease Assessment in the Treatment of Children and Adolescents with Intermediate-Risk (Stage III/IV) B-Cell Non-Hodgkin Lymphoma: A Children’s Oncology Group Report

    OpenAIRE

    Shiramizu, Bruce; Goldman, Stanton; Kusao, Ian; Agsalda, Melissa; Lynch, James; Smith, Lynette; Harrison, Lauren; Morris, Erin; Gross, Thomas G.; Sanger, Warren; Perkins, Sherrie; Cairo, Mitchell S

    2011-01-01

    Children/adolescents with mature B-cell non-Hodgkin lymphoma (B-NHL) have an excellent prognosis but relapses still occur. While chromosomal aberrations and/or clonal immunoglobulin (Ig) gene rearrangements may indicate risk of failure, a more universal approach was developed to detect minimal disease (MD). Children/adolescents with intermediate-risk B-NHL were treated with French-British-American/Lymphome Malins de Burkitt 96 (FAB/LMB96) B4 modified chemotherapy and rituximab. Specimens from...

  17. Evaluation of a Minimally Invasive Cell Sampling Device Coupled with Assessment of Trefoil Factor 3 Expression for Diagnosing Barrett's Esophagus: A Multi-Center Case–Control Study

    OpenAIRE

    Ross-Innes, Caryn S.; Irene Debiram-Beecham; Maria O'Donovan; Elaine Walker; Sibu Varghese; Pierre Lao-Sirieix; Laurence Lovat; Michael Griffin; Krish Ragunath; Rehan Haidry; Sami, Sarmed S.; Philip Kaye; Marco Novelli; Babett Disep; Richard Ostler

    2015-01-01

    Editors' Summary Background Barrett's esophagus is a condition in which the cells lining the esophagus (the tube that transports food from the mouth to the stomach) change and begin to resemble the cells lining the intestines. Although some people with Barrett's esophagus complain of burning indigestion or acid reflux from the stomach into the esophagus, many people have no symptoms or do not seek medical advice, so the condition often remains undiagnosed. Long-term acid reflux (gastroesophag...

  18. Low cost sprayed CdTe solar cell research. First quarterly progress report, 15 August-14 November 1979

    Energy Technology Data Exchange (ETDEWEB)

    Sienkiewicz, P.; Lis, S.; Serreze, H.B.; Entine, G.

    1979-12-01

    During the first quarter of this contract, facilities for the spray pyrolysis deposition of CdTe thin films using a process anolagous to that used to spray deposit device-quality films of CdS were prepared. A Te salt, ..beta..-(CH/sub 3/)/sub 2/TeI/sub 2/, suitable for use in the spray process was synthesized. The facilities were shown to function properly by the successful spraying of good quality CdS thin films. A number of initial spray experiments were conducted utilizing the ..beta..-(CH/sub 3/)/sub 2/TeI/sub 2/ and other inorganic tellurium-bearing compounds which also show great promise in producing low-cost sprayed CdTe solar cells. Initial chemical tests of these films indicated the presence of both Cd and Te, and x-ray diffraction analysis is presently underway to determine the actual concentration of CdTe.

  19. Surface morphology and impurity distribution of electron beam recrystallized silicon films on low cost substrates for solar cell absorber

    Institute of Scientific and Technical Information of China (English)

    FU Li; GROMBALL F; MüLLER J

    2006-01-01

    A line shaped electron beam recrystallised polycrystalline silicon film on the low cost substrate was investigated for the use of the solar cell absorber. The applied EB energy density strongly influences the surface morphology of the film system. Lower EB energy density results in droplet morphology and the rougher SiO2 capping layer due to the low fluidity. With the energy increasing, thecapping layer becomes smooth and continuous and less and small pinholes form in the silicon film. Tungstendisilicide (WSi2) is formed at the interface tungsten/silicon but also at the grain boundaries of the silicon. Because of the fast melting and cooling of the silicon film, the eutectic of silicon and tungstendisilicide mainly forms at the grain boundary of the primary silicon dendrites. The SEM-EDX analysis shows that there are no chlorine and hydrogen in the area surrounding a pinhole after recrystallization because of outgassing during the solidification.

  20. Development of low cost ceramic separator using mineral cation exchanger to enhance performance of microbial fuel cells

    International Nuclear Information System (INIS)

    This study deals with the development of ceramic separator (CS) made from red soil blended with cation exchanger, Montmorillonite and Kaolinite, for its application in microbial fuel cells (MFCs). The separators were characterized in terms of conductivity, oxygen, acetate and proton diffusion, and ion transport ability. Performance of MFCs using different CS was evaluated under batch mode of operation. MFC M-20 (CS blended with 20% Montmorillonite) exhibited maximum power density of 7.5 W/m3 which was 48% higher than MFC without exchanger (Control) and 30%, 9%, 27% higher than MFC M-10 (10% Montmorillonite), MFC M-15 (15% Montmorillonite), MFC K-20 (20% Kaolinite), respectively. Coulombic efficiency of MFC M-20 (30%) and MFC K-20 (23%) was higher compared to control (18%). Use of cation exchangers improved properties of ceramic separators compared to control. Higher cation exchange capacity (CEC) of Montmorillonite (150 meq/100 g) resulted in 4 fold decrease in charge transfer resistance (3.4 Ω) and 1.8 fold increase in conductivity (5.56 × 10−4 S/cm) of CS as compared to Kaolinite. This study demonstrates that Montmorillonite incorporated CS proved to be suitable alternative to replace costly polymeric membrane to increase power output of MFC at reduced cost

  1. The Cost-Utility Analysis of PET-Scan in Diagnosis and Treatment of Non-Small Cell Lung Carcinoma in Iran

    International Nuclear Information System (INIS)

    PET scan is a non-invasive, complex and expensive medical imaging technology that is normally used for the diagnosis and treatment of various diseases including lung cancer. The purpose of this study is to assess the cost effectiveness of this technology in the diagnosis and treatment of non- small cell lung carcinoma (NSCLC) in Iran. The main electronic databases including The Cochrane Library and Medline were searched to identify available evidence about the performance and effectiveness of technology. A standard decision tree model with seven strategies was used to perform the economic evaluation. Retrieved studies and expert opinion were used to estimate the cost of each treatment strategy in Iran. The costs were divided into three categories including capital costs (depreciation costs of buildings and equipment), staff costs and other expenses (including cost of consumables, running and maintenance costs). The costs were estimated in both IR-Rials and US-Dollars with an exchange rate of 10.000 IR Rials per one US Dollar according to the exchange rate in 2008. The total annual running cost of a PET scan was about 8850 to 13000 million Rials, (0.9 to 1.3 million US$). The average cost of performing a PET scan varied between 3 and 4.5 million Rials (300 to 450US$). The strategies 3 (mediastinoscopy alone) and 7 (mediastinoscopy after PET scan) were more cost-effective than other strategies, especially when the result of the CT-scan performed before PET scan was negative. The technical performance of PET scan is significantly higher than similar technologies for staging and treatment of NSCLC. In addition, it might slightly improve the treatment process and lead to a small level of increase in the quality adjusted life year (QALY) gained by these patients making it cost-effective for the treatment of NSCLC

  2. Development of a Low-Cost, Durable Membrane and MEA for Stationary and Mobile Fuel Cell Applications

    Energy Technology Data Exchange (ETDEWEB)

    Michel Foure, Scott Gaboury, Jim Goldbach, David Mountz and Jung Yi (no longer with company)

    2008-01-31

    The development of low cost, durable membranes and membranes electrode assemblies (MEAs) remain a critical challenge for the successful introduction of fuel cells into mass markets. It was the goal of the team lead by Arkema, Inc. (formerly Atofina, Inc.) to address these shortages. Thus, this project addresses the following technical barriers from the Fuel Cells section of the Hydrogen Fuel Cells and Infrastructure Technologies Program Multi-Year Research, Development and Demonstration Plan: (A) Durability (B) Cost Arkema’s approach consisted in using blends of polyvinylidenefluoride (PVDF) and proprietary sulfonated polyelectrolytes. The strength and originality of Arkema’s approach lies in the decoupling of ion conductivity from the other requirements. Kynar® (Arkema trade name for PVDF) provides an exceptional combination of properties that make it ideally suited for a membrane matrix. In a first phase, Arkema demonstrated the feasibility of the concept with the M31 membrane generation. After MEA optimization, it was shown that the beginning-of-life (BOL) performance of M31 MEAs was essentially on a par with that of PFSA MEAs at 60ºC under fully humidified conditions. On the other hand, long-term durability studies showed a high decay rate of 45µV/h over a 2100 hr. test. Arkema then designed several families of polyelectrolyte candidates, which – in principle – could not undergo the same failure mechanisms. A new membrane candidate was developed: M41. It offered the same generally good mechanical, ex-situ conductivity and gas barrier properties as M31. In addition, ex-situ accelerated testing suggested a several orders of magnitude improvement in chemical stability. M41 based MEAs showed comparable BOL performance with that of PFSA (80ºC, 100% RH). M41 MEAs were further shown to be able to withstand several hours temperature excursions at 120ºC without apparent damage. Accelerated studies were carried out using the DOE and/or US Fuel Cell Council

  3. Development of a Low-Cost, Durable Membrane and Membrane Electrode Assemby for Stationary and Mobile Fuel Cell Applications

    Energy Technology Data Exchange (ETDEWEB)

    Foure, Michel; Gaboury, Scott; Goldbach, Jim; Mountz, David; Yi, Jung

    2008-01-31

    The development of low cost, durable membranes and membranes electrode assemblies (MEAs) remain a critical challenge for the successful introduction of fuel cells into mass markets. It was the goal of the team lead by Arkema, Inc. (formerly Atofina, Inc.) to address these shortages. Thus, this project addresses the following technical barriers from the Fuel Cells section of the Hydrogen Fuel Cells and Infrastructure Technologies Program Multi-Year Research, Development and Demonstration Plan: (A) Durability (B) Cost Arkema’s approach consisted in using blends of polyvinylidenefluoride (PVDF) and proprietary sulfonated polyelectrolytes. The strength and originality of Arkema’s approach lies in the decoupling of ion conductivity from the other requirements. Kynar® (Arkema trade name for PVDF) provides an exceptional combination of properties that make it ideally suited for a membrane matrix. In a first phase, Arkema demonstrated the feasibility of the concept with the M31 membrane generation. After MEA optimization, it was shown that the beginning-of-life (BOL) performance of M31 MEAs was essentially on a par with that of PFSA MEAs at 60ºC under fully humidified conditions. On the other hand, long-term durability studies showed a high decay rate of 45µV/h over a 2100 hr. test. Arkema then designed several families of polyelectrolyte candidates, which, in principle, could not undergo the same failure mechanisms. A new membrane candidate was developed: M41. It offered the same generally good mechanical, ex-situ conductivity and gas barrier properties as M31. In addition, ex-situ accelerated testing suggested a several orders of magnitude improvement in chemical stability. M41 based MEAs showed comparable BOL performance with that of PFSA (80ºC, 100% RH). M41 MEAs were further shown to be able to withstand several hours temperature excursions at 120ºC without apparent damage. Accelerated studies were carried out using the DOE and/or US Fuel Cell Council

  4. COST MEASUREMENT AND COST MANAGEMENT IN TARGET COSTING

    Directory of Open Access Journals (Sweden)

    Moisello Anna Maria

    2012-07-01

    Full Text Available Firms are coping with a competitive scenario characterized by quick changes produced by internationalization, concentration, restructuring, technological innovation processes and financial market crisis. On the one hand market enlargement have increased the number and the segmentation of customers and have raised the number of competitors, on the other hand technological innovation has reduced product life cycle. So firms have to adjust their management models to this scenario, pursuing customer satisfaction and respecting cost constraints. In a context where price is a variable fixed by the market, firms have to switch from the cost measurement logic to the cost management one, adopting target costing methodology. The target costing process is a price driven, customer oriented profit planning and cost management system. It works, in a cross functional way, from the design stage throughout all the product life cycle and it involves the entire value chain. The process implementation needs a costing methodology consistent with the cost management logic. The aim of the paper is to focus on Activity Based Costing (ABC application to target costing process. So: -it analyzes target costing logic and phases, basing on a literary review, in order to highlight the costing needs related to this process; -it shows, through a numerical example, how to structure a flexible ABC model – characterized by the separation between variable, fixed in the short and fixed costs - that effectively supports target costing process in the cost measurement phase (drifting cost determination and in the target cost alignment; -it points out the effectiveness of the Activity Based Costing as a model of cost measurement applicable to the supplier choice and as a support for supply cost management which have an important role in target costing process. The activity based information allows a firm to optimize the supplier choice by following the method of minimizing the

  5. Flow cytometric characterization of culture expanded multipotent mesenchymal stromal cells (MSCs) from horse adipose tissue: towards the definition of minimal stemness criteria.

    Science.gov (United States)

    Pascucci, L; Curina, G; Mercati, F; Marini, C; Dall'Aglio, C; Paternesi, B; Ceccarelli, P

    2011-12-15

    In the last decades, multipotent mesenchymal progenitor cells have been isolated from many adult tissues of different species. The International Society for Cellular Therapy (ISCT) has recently established that multipotent mesenchymal stromal cells (MSCs) is the currently recommended designation. In this study, we used flow cytometry to evaluate the expression of several molecules related to stemness (CD90, CD44, CD73 and STRO-1) in undifferentiated, early-passaged MSCs isolated from adipose tissue of four donor horses (AdMSCs). The four populations unanimously expressed high levels of CD90 and CD44. On the contrary, they were unexpectedly negative to CD73. A small percentage of the cells, finally, showed the expression of STRO-1. This last result might be due to the existence of a small subpopulation of STRO-1+ cells or to a poor cross-reactivity of the antibody. A remarkable donor-to-donor consistency and reproducibility of these findings was demonstrated. The data presented herein support the idea that equine AdMSCs may be easily isolated and selected by adherence to tissue culture plastic and exhibit a surface profile characterized by some peculiar differences in comparison to those described in other species. Continued characterization of these cells will help to clarify several aspects of their biology and may ultimately enable the isolation of specific, purified subpopulations. PMID:21839521

  6. Minimally invasive mediastinal surgery.

    Science.gov (United States)

    Melfi, Franca M A; Fanucchi, Olivia; Mussi, Alfredo

    2016-01-01

    In the past, mediastinal surgery was associated with the necessity of a maximum exposure, which was accomplished through various approaches. In the early 1990s, many surgical fields, including thoracic surgery, observed the development of minimally invasive techniques. These included video-assisted thoracic surgery (VATS), which confers clear advantages over an open approach, such as less trauma, short hospital stay, increased cosmetic results and preservation of lung function. However, VATS is associated with several disadvantages. For this reason, it is not routinely performed for resection of mediastinal mass lesions, especially those located in the anterior mediastinum, a tiny and remote space that contains vital structures at risk of injury. Robotic systems can overcome the limits of VATS, offering three-dimensional (3D) vision and wristed instrumentations, and are being increasingly used. With regards to thymectomy for myasthenia gravis (MG), unilateral and bilateral VATS approaches have demonstrated good long-term neurologic results with low complication rates. Nevertheless, some authors still advocate the necessity of maximum exposure, especially when considering the distribution of normal and ectopic thymic tissue. In recent studies, the robotic approach has shown to provide similar neurological outcomes when compared to transsternal and VATS approaches, and is associated with a low morbidity. Importantly, through a unilateral robotic technique, it is possible to dissect and remove at least the same amount of mediastinal fat tissue. Preliminary results on early-stage thymomatous disease indicated that minimally invasive approaches are safe and feasible, with a low rate of pleural recurrence, underlining the necessity of a "no-touch" technique. However, especially for thymomatous disease characterized by an indolent nature, further studies with long follow-up period are necessary in order to assess oncologic and neurologic results through minimally invasive

  7. Material research on amorphous silicon based alloys: Application to low-cost efficient solar cells

    International Nuclear Information System (INIS)

    Amorphous silicon solar cell technology has reached a high level of maturity, which is the result of several years of basic research and of an unprecedented industrial effort. It already occupies an unchallenged position for micro-power and indoor applications like light-powered calculators, watches, etc. With the presently available material, the technological improvements have practically reached their limits and little can be gained on the open voltage or the fill factor. The only substantial improvement to be expected is an increase in the short-circuit current by a better matching of the optical gap to the solar spectrum. In principle, one could almost double the short-circuit current by a moderate decrease of the optical gap from 1.8 eV to 1.4 eV. Unfortunately, the proper small-gap material, having good photovoltaic properties, still remains to be found and this is the subject of material research activities in many laboratories in the world. 17 refs, 4 figs

  8. [Development of a low-cost single chamber microbial fuel cell type BOD sensor].

    Science.gov (United States)

    Wu, Feng; Liu, Zhi; Zhou, Ben; Zhou, Shun-gui; Rao, Li-qun; Wang, Yue-qiang

    2010-07-01

    The principle of the detector is based on the effect of microbial toxicity of water sample on the electricity generation in microbial fuel cell (MFC). The performance of the MFC-type biotoxicity detector was evaluated with the synthetic water containing heavy metals of Cd2+ and Cu2+. The experimental results demonstrated that: (1) relative to the conventional methods, the MFC-type detector is easy to operate, and suitable for on-line measurements with high sensitivity; (2) it only requires 4 h to complete measurements, and can get ready for next measurement within 4 h; (3) there is a significant linear correlation between the concentration of toxic metal(s) and inhibition ratios in Coulombic yields of MFC. As the IC20 (concentration causing 20% inhibition) of Cd2+, Cu2+ and mixed metals (Cd2+ and Cu2+) were 0.6, 0.8 and 0.25 mg/L, the regression coefficients were shown to be 0.9960, 0.9744 and 0.9907. PMID:20825031

  9. Minimal noncanonical cosmologies

    International Nuclear Information System (INIS)

    We demonstrate how much it is possible to deviate from the standard cosmological paradigm of inflation-assisted ΛCDM, keeping within current observational constraints, and without adding to or modifying any theoretical assumptions. We show that within a minimal framework there are many new possibilities, some of them wildly different from the standard picture. We present three illustrative examples of new models, described phenomenologically by a noncanonical scalar field coupled to radiation and matter. These models have interesting implications for inflation, quintessence, reheating, electroweak baryogenesis, and the relic densities of WIMPs and other exotics

  10. Minimally Invasive Lumbar Discectomy

    Medline Plus

    Full Text Available ... they support that, do they show that quicker recovery times, cost effectiveness, and is this covered by insurance? Oh, it’s covered by insurance, and it’s great for the patients, and, indeed, it’s better recovery, and they do very well. Again, if you ...

  11. Multiple objectives application approach to waste minimization

    Institute of Scientific and Technical Information of China (English)

    张清宇

    2002-01-01

    Besides economics and controllability, waste minimization has now become an obje ctive in designing chemical processes, and usually leads to high costs of invest ment and operation. An attempt was made to minimize waste discharged from chemic al reaction processes during the design and modification process while the opera tion conditions were also optimized to meet the requirements of technology and e conomics. Multiobjectives decision nonlinear programming (NLP) was employed to o ptimize the operation conditions of a chemical reaction process and reduce waste . A modeling language package-SPEEDUP was used to simulate the process. This p aper presents a case study of the benzene production process. The flowsheet factors affecting the economics and waste generation were examined. Constraints were imposed to reduce the number of objectives and carry out optimal calculations e asily. After comparisons of all possible solutions, best-compromise approach wa s applied to meet technological requirements and minimize waste.

  12. Multiple objectives application approach to waste minimization

    Institute of Scientific and Technical Information of China (English)

    张清宇

    2002-01-01

    Besides econormics and controllability, waste minimization has now become an objective in designing chemical processes,and usually leads to high costs of investment and operation.An attempt was mede to minimize waste discharged from chemical reaction processes during the design and modification process while the operation conditions were also optimized to meet the requirements of technology and economics.Multiob-jectives decision nonlinear programming(NLP) was emplyed optimize the operation conditions of a chemical reaction process and reduce waste. A modeling package-SPEEDUP was used to simulate the process.This paper presents a case study of the benzenc production process.The flowsheer factors affecting the economics and waste generation were examined.Constraints were imposed to reduce the number of objectives and carry out optimal calculations easily.After comparisons of all possiblle solutions,best-compromise approach was applied to meet technological requirements and minimize waste.

  13. The minimal sequence essential for replication and movement of Cotton leaf curl Multan betasatellite DNA by a helper virus in plant cells.

    Science.gov (United States)

    Eini, Omid; Behjatnia, S A Akbar

    2016-10-01

    Betasatellites are single-stranded circular DNAs associated with a number of monopartite begomoviruses. Betasatellites rely on the helper begomoviruses for replication and movement in plant tissues and plant-to-plant transmission by vectors. Their genomes are approximately half the size of the helper viruses and consist of three main regions including the βC1 gene, an adenine-rich (A-rich) region, and the satellite conserved region (SCR). In this study, we investigated the minimal sequences required for Cotton leaf curl Multan betasatellite (CLCuMB) replication and movement. Mutational analysis of CLCuMB DNA genome indicated that βC1 gene and A-rich region were not required for trans-replication and movement of CLCuMB in host plants by a helper virus. Deletion of βC1 gene and a fragment (135 nt in length) upstream of this gene impaired CLCuMB replication. However, CLCuMB mutant with deletion of βC1 gene and a further 163 nucleotides replicated at a lower level as compared to the wild-type betasatellite. This suggests that there are essential elements in the fragment upstream of βC1 gene, which are required for the replication of CLCuMB rather than the size limitation of CLCuMB DNA. PMID:27193570

  14. Minimal Higgs inflation

    CERN Document Server

    Maity, Debaprasad

    2016-01-01

    In this paper we propose two simple minimal Higgs inflation scenarios through a simple modification of the Higgs potential, as opposed to the usual non-minimal Higgs-gravity coupling prescription. The modification is done in such a way that it creates a flat plateau for a huge range of field values at the inflationary energy scale $\\mu \\simeq (\\lambda)^{1/4} \\alpha$. Assuming the perturbative Higgs quartic coupling, $\\lambda \\simeq {\\cal O}(1)$, for both the models inflation energy scale turned out to be $\\mu \\simeq (10^{14}, 10^{15})$ GeV, and prediction of all the cosmologically relevant quantities, $(n_s,r,dn_s^k)$, fit extremely well with observations made by PLANCK. Considering observed central value of the scalar spectral index, $n_s= 0.968$, our two models predict efolding number, $N = (52,47)$. Within a wide range of viable parameter space, we found that the prediction of tensor to scalar ratio $r (\\leq 10^{-5})$ is far below the current experimental sensitivity to be observed in the near future. The ...

  15. Decision-tree sensitivity analysis for cost-effectiveness of whole-body FDG PET in the management of patients with non-small-cell lung carcinoma in Japan

    International Nuclear Information System (INIS)

    Whole-body 2-fluoro-2-D-[18F]deoxyglucose[FDG] positron emission tomography (WB-PET) may be more cost-effective than chest PET because WB-PET does not require conventional imaging (CI) for extrathoracic staging. The cost-effectiveness of WB-PET for the management of Japanese patients with non-small-cell lung carcinoma (NSCLC) was assessed. Decision-tree sensitivity analysis was designed, based on the two competing strategies of WB-PET vs. CI. WB-PET was assumed to have a sensitivity and specificity for detecting metastases, of 90% to 100% and CI of 80% to 90%. The prevalences of M1 disease were 34% and 20%. On thousand patients suspected of having NSCLC were simulated in each strategy. We surveyed the relevant literature for the choice of variables. Expected cost saving (CS) and expected life expectancy (LE) for NSCLC patients were calculated. The WB-PET strategy yielded an expected CS of $951 US to $1,493 US per patient and an expected LE of minus 0.0246 years to minus 0.0136 years per patient for the 71.4% NSCLC and 34% M1 disease prevalence at our hospital. PET avoided unnecessary bronchoscopies and thoracotomies for incurable and benign disease. Overall, the CS for each patient was $833 US to $2,010 US at NSCLC prevalences ranging from 10% to 90%. The LE of the WB-PET strategy was similar to that of the CI strategy. The CS and LE minimally varied in the two situations of 34% and 20% M1 disease prevalence. The introduction of a WB-PET strategy in place of CI for managing NSCLC patients is potentially cost-effective in Japan. (author)

  16. Linear Superposition of Minimal Surfaces: Generalized Helicoids and Minimal Cones

    OpenAIRE

    Hoppe, Jens

    2016-01-01

    Observing a linear superposition principle, a family of new minimal hypersurfaces in Euclidean space is found, as well as that linear combinations of generalized helicoids induce new algebraic minimal cones of arbitrarily high degree.

  17. IL-12 immunotherapy of minimal residual disease in murine models of HPV16-associated tumours: induction of immune responses, cytokine production and kinetics of immune cell subsets

    Czech Academy of Sciences Publication Activity Database

    Indrová, Marie; Bieblová, Jana; Bubeník, Jan; Reiniš, Milan

    2008-01-01

    Roč. 32, č. 2 (2008), s. 499-507. ISSN 1019-6439 R&D Projects: GA ČR GA301/06/0774 EU Projects: European Commission(XE) 18933 - CLINIGENE Institutional research plan: CEZ:AV0Z50520514 Keywords : HPV 16 * MHC class I-positive and -deficient tumours * immature myeloid cells Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.234, year: 2008

  18. Phase I study of temozolomide in combination with thiotepa and carboplatin with autologous hematopoietic cell rescue in patients with malignant brain tumors with minimal residual disease.

    Science.gov (United States)

    Egan, G; Cervone, K A; Philips, P C; Belasco, J B; Finlay, J L; Gardner, S L

    2016-04-01

    Recurrence of malignant brain tumors results in a poor prognosis with limited treatment options. High-dose chemotherapy with autologous hematopoietic cell rescue (AHCR) has been used in patients with recurrent malignant brain tumors and has shown improved outcomes compared with standard chemotherapy. Temozolomide is standard therapy for glioblastoma and has also shown activity in patients with medulloblastoma/primitive neuro-ectodermal tumor (PNET), particularly those with recurrent disease. Temozolomide was administered twice daily on days -10 to -6, followed by thiotepa 300 mg/m(2) per day and carboplatin dosed using the Calvert formula or body surface area on days -5 to -3, with AHCR day 0. Twenty-seven patients aged 3-46 years were enrolled. Diagnoses included high-grade glioma (n=12); medulloblastoma/PNET (n=9); central nervous system (CNS) germ cell tumor (n=4); ependymoma (n=1) and spinal cord PNET (n=1). Temozolomide doses ranged from 100 mg/m(2) per day to 400 mg/m(2) per day. There were no toxic deaths. Prolonged survival was noted in several patients including those with recurrent high-grade glioma, medulloblastoma and CNS germ cell tumor. Increased doses of temozolomide are feasible with AHCR. A phase II study using temozolomide, carboplatin and thiotepa with AHCR for children with recurrent malignant brain tumors is being conducted through the Pediatric Blood and Marrow Transplant Consortium. PMID:26726947

  19. Enhanced expression of full-length human cytomegalovirus fusion protein in non-swelling baculovirus-infected cells with a minimal fed-batch strategy.

    Directory of Open Access Journals (Sweden)

    Marco Patrone

    Full Text Available Human cytomegalovirus congenital infection represents an unmet medical issue and attempts are ongoing to develop an effective vaccine. The virion fusion players of this enveloped virus are the natural targets to achieve this goal and to develop novel anti-viral therapies. The secreted ectodomain of the viral fusion factor glycoprotein B (gB has been exploited so far as an alternative to the cumbersome expression of the wild type trans-membrane protein. In the soluble form, gB showed encouraging but limited potential as antigen candidate calling for further efforts. Here, the exhaustive evaluation of the Baculovirus/insect cell expression system has been coupled to an orthogonal screening for expression additives to produce full-length gB. In detail, rapamycin was found to prolong gB intracellular accumulation while inhibiting the infection-induced cell swelling. Not obvious to predict, this inhibition did not affect Baculovirus growth, revealing that the virus-induced cell size increase is a dispensable side phenotype. In parallel, a feeding strategy for the limiting nutrient cysteine has been set up which improved gB stability. This multi-modal scheme allowed the production of full-length, mutation-free gB in the milligram scale. The recombinant full-length gB obtained was embedded into a stable mono-dispersed particle substantially larger than the protein trimer itself, according to the reported association of this protein with detergent-resistant lipid domains.

  20. The Differential Diagnosis Of Minimal Fat Renal Angiomyolipoma with Subtypes Of Renal Cell Carcinoma%肾乏脂肪血管平滑肌脂肪瘤与肾癌亚型的CT鉴别诊断

    Institute of Scientific and Technical Information of China (English)

    刘凯; 曾自三

    2015-01-01

    目的:分析肾血管平滑肌脂肪瘤(Angiomyolipoma,AML)与肾癌亚型的CT表现,评价多层螺旋CT在肾乏脂肪AML与肾癌亚型的诊断与鉴别诊断价值。方法回顾性分析21例肾乏脂肪AML21例及93例肾癌(其中肾透明细胞癌73例,肾乳头状细胞癌11例,肾嫌色细胞癌9例)CT影像,比较肾乏脂肪AML与肾癌常见亚型MSCT多期扫描影像学表现,并用统计学软件(SPSS 18.0)进行统计学分析。结果薄层重建肾乏脂肪AML组发现微脂肪区域10例,占47.6%,肾癌组仅2例,均为透明细胞癌,两组比较有显著性差异(P<0.05)。肾透明细胞癌皮质期增强程度、排泄期衰减程度均大于肾乏脂肪AML(P<0.05),肾透明细胞癌大多呈不均匀强化而肾乏脂肪AML为均匀强化的居多(P<0.05)。肾乏脂肪AML在皮质期、实质期、排泄期的强化程度均大于肾乳头状细胞癌及嫌色细胞癌(P<0.05),而强化模式的比较无显著性差异(P>0.05)。结论薄层重建仔细寻找肿瘤内有无微脂肪成分是鉴别肾乏脂肪AML与肾癌的关键;对于无可见脂肪的肾AML,肿瘤的强化程度、强化模式是鉴别的重要手段,且需考虑到肾癌亚型的因素综合分析。少数不典型的良性肿瘤鉴别困难,应结合临床综合分析,必要时行活检,避免误诊导致过度治疗。%Objective To analyze the CT findings in renal angiomyolipoma with minimal fat and subtypes of renal cell carcinoma, and have a value evaluation of MSCT diagnosis and differential diagnosis of renal angiomyolipoma with minimal fat and subtypes of renal cell carcinoma.Methods A retrospective analysis was carried out on CT images of 21 cases of minimal fat renal angiomyolipomas and 98 cases of renal cell carcinoma (including 73 cases of clear cell renal carcinoma, 11 cases of papillary renal cell carcinoma, 9 cases of chromophobe renal cell carcinoma). The differences of CT imaging features were compared