July 2011 - Allocations-admins - mailman3.cels.anl.gov

[LCRC Accounts] Project Request: UQCLM
by accounts＠lcrc.anl.gov 29 Jul '11

29 Jul '11

Hello, A new project on the LCRC cluster has been requested. Please forward the information on to the LCRC Allocation sub-committee. Applicant's name: Mihai Anitescu Applicant's institution: ANL Applicant's division: MCS Project Name: UQCLM Project title: Uncertainty Quantification for Land Model in Climate Science Associated funding: Climate Science for a Sustainable Energy Future; PI: Mihai Anitescu; site PI: Ian Foster Other Systems: Science: In this project we study uncertainty quantification (UQ) methods applied to Community Land Model (CLM). CLM is the land model for the Community Earth System Model (CESM) and the Community Atmosphere Model (CAM). It consists of several sets of large and nonlinear complex systems. We aim to develop intrusive uncertainty quantification methods and to demonstrate their computational advantage over a differentiated version of CLM with automatic differentiation (OpenAD) which will open the way for gradient-based optimization for calibration in land testbed. Project description: The overall UQ approach comprises three parts: sensitivity characterization, uncertainty model calibration, and uncertainty propagation, each of which is computationally intensive. The first two tasks require the creation and use of derivative information. Our scientific goal is to applied the developed UQ tools to the land model. First, we will characterize the sensitivity of the outputs to model parameters, for example, the physiology inputs for vegetation and atmosphere forcing. By using OpenAD, we can use derivative information for obtaining the sensitivity and guide the choice of statistical models. Subsequently, we will use a parallel gradient-based optimization tool built around the stochastic programming code PIPS to do calibration of uncertain parameters with local data sets. After that we can use those tuned parameters to quantify prediction and finally, make overall estimate of prediction uncertainty. This approach is implemented as an iterative process, repeated as new observational data set become available. By doing so, land UQ results will be useful in guiding subsequent observational campaigns, leading to improved estimates of parameters with maximal impact on reducing the prediction uncertainty. We plan first to do comparisons between finite difference intrusive approaches versus a Monte Carlo approach for single point models and initial assessment of AD application to CLM. We will also make comparison between finite difference intrusive sensitivity analysis approaches versus a Monte Carlo sensitivity analysis approach for single point models. After validations for single points, we will proceed at the global gridded scale and coupled clm models. This project requires intensive computations due to the ensemble nature of the calculation and to the need to make assessments on steady-state quantities, which requires runs to stabilization. We need to prototype and test the interface with the OpenAD tool and test our numerical codes for runs on a global scale of more than 1,000 years with hundreds of perturbed parameters. Project URL: Requested allocation: 90000 Justification: The requester has used 0 hours of their initial startup project. In addition to approving an initial amount, please specify a Category and Subcategory for this project. For a list of the current selection of approved categories, please see: https://wiki.lcrc.anl.gov/wiki/Processes/Categories Once the Allocation committee has approved the project, please go to the Project Management page to create it: https://accounts.lcrc.anl.gov/projects.php Thank You, The LCRC Accounts System

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[LCRC Accounts] Project Request: DVI_Materials
by accounts＠lcrc.anl.gov 29 Jul '11

29 Jul '11

Hello, A new project on the LCRC cluster has been requested. Please forward the information on to the LCRC Allocation sub-committee. Applicant's name: Barry Smith Applicant's institution: ANL Applicant's division: MCS Project Name: DVI_Materials Project title: DVI Solvers for Material Science Associated funding: DOE ASCR ARPA-E, FASTMath SciDAC Other Systems: Science: This project uses differential variational inequalities (DVIs) for heterogeneous materials problems, which describe the mesoscale behavior of irradiate damaged materials, for example in a nuclear reactor. The phase field approach is used for modeling microstructure in the mesoscale. Since the diffuse boundary between phases must be localized, one needs to use double obstacle potentials for generating the free energy functional. This results in a differential variational inequality. Our aim is to develop algorithms and software for large-scale DVIs in collaboration with material scientists. Project description: IWe employ coupled Cahn-Hilliard and Allen-Cahn systems with a double obstacle free energy potential to simulate the physics. The model is discretized in time with mixed implicit-explicit integration and in space by finite elements. However, a naive finite element approximation does not guarantee that the discrete solution satifises appropriate constraints. Therefore, we formulate a DVI, which is equivalent to a complementarity problem and provides bounds on the constrained variables This approach in turn allows us to use parallel solvers for complementarity problems in PETSc. We have validated the DVI approach agains the baseline results of the Center for Materials Science of Nuclear Fuel^M(CMSNF). We employed much larger time steps than the conventional finite difference and finite element methods, which is one of the projected benets of the DVI formulation.We have completed preliminary numerical experiments and mathematical analysis for both the Allen-Cahn and Cahn-Hilliard systems that demonstrate mesh-independent convergence rates for this preconditioner. That is, the work required to solve a single timestep grows linearly with the number of unknowns. For now we are making 2 dimensional runs and hope to use at least a 1000 by 1000 grids, with 5 degrees of freedom per grid point and hence at least 5 million unknowns. At each time step one must solve a sequence of linear problems of varying sizes with around 5 million degrees of freedom. We are using the geometric multigrid in PETSc for the linear solves. On a workstation for 100 by 100 grids it takes about 30 seconds per grid point. We plan to use the Intel compilers and MPI, later we may use hybrid programming within a node but for initial work it is all MPI. Project members: Barry Smith, Lois McInnes, Satish Balay, Mihai Amotesci, Todd Munson, Jungho Lee, Lei Wang. Project URL: Requested allocation: 50000 Justification: The requester has used 0 hours of their initial startup project. In addition to approving an initial amount, please specify a Category and Subcategory for this project. For a list of the current selection of approved categories, please see: https://wiki.lcrc.anl.gov/wiki/Processes/Categories Once the Allocation committee has approved the project, please go to the Project Management page to create it: https://accounts.lcrc.anl.gov/projects.php Thank You, The LCRC Accounts System

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Re: [allocations-admins] [lcrc-core] Fwd: [LCRC Accounts] Project Request: MD_solvent_mixtures
by John J. Low 28 Jul '11

28 Jul '11

Could we allocate 100K to this project now and then review the full request and the next allocation meeting? ----- Original Message ----- From: "Sanket Avinash Deshmukh" <sanket(a)anl.gov> To: "John J. Low" <jlow(a)zimbra.mcs.anl.gov> Sent: Thursday, July 28, 2011 10:17:02 AM Subject: Re: [lcrc-core] Fwd: [allocations-admins] [LCRC Accounts] Project Request: MD_solvent_mixtures Hi John, Yes, I will be glad to have any additional time you can give to me for this year. 100K or if possible more than 100K is also okay for this year. As per your suggestion I will apply for additional time next year. I am using LAMMPS molecular dynamics simulation package. So far I have used it on Carbon (CNM cluster) and on Fusion. It scales very well on Fusion for the polymer systems that I am studying. Thank you. Regards, Sanket On Jul 27, 2011, at 4:32 PM, John J. Low wrote: > Sanket, > > It would be difficult to allocate 800K core-hours this fiscal year which ends this quarter. This is a large fraction of the core-hours available on Fusion until the end of the September (approximately 5M core-hours). It would be much easier to allocate 100K core-hours to this project for this quarter (until the end of September). You could request an additional 700K core-hours for next year. Would that be acceptable? > > Please tell us what software you will be using in this project. > > John J. Low > Computational Scientist-STA > Mathematics and Computer Science > Building 240, 1.G.10 > 9700 South Cass Avenue > Argonne National Laboratory > Argonne, IL 60439. > 630-252-0045 > > > > ----- Forwarded Message ----- > From: "John Valdes" <valdes(a)mcs.anl.gov> > To: lcrc-core(a)lcrc.anl.gov > Sent: Wednesday, July 27, 2011 2:41:24 PM > Subject: [lcrc-core] Fwd: [allocations-admins] [LCRC Accounts] Project Request: MD_solvent_mixtures > > ----- Forwarded message from accounts(a)lcrc.anl.gov ----- > > Date: Thu, 21 Jul 2011 13:32:47 -0500 (CDT) > From: accounts(a)lcrc.anl.gov > To: allocations-admins(a)lcrc.anl.gov > Subject: [allocations-admins] [LCRC Accounts] Project Request: > MD_solvent_mixtures > Reply-To: accounts(a)lcrc.anl.gov > > Hello, > > A new project on the LCRC cluster has been requested. Please forward > the information on to the LCRC Allocation sub-committee. > > Applicant's name: Sanket Deshmukh > Applicant's institution: ANL > Applicant's division: CNM > Project Name: MD_solvent_mixtures > Project title: Atomistic simulations to understand the effect of Water/Methanol Solvent Mixtures on the Lower Critical Solution Temperature of poly(N-isopropylacrylamide) > Associated funding: > Other Systems: Carbon (CNM) > Science: PNIPAM is a thermo-sensitive polymer that has a lower critical solution temperature (LCST) around 305K in aqueous solution.1 As the LCST of PNIPAM is close to human body temperature, it is a serious contender for a controlled drug delivery system.2,3 Coil-to-globule transition occurs in PNIPAM when temperature is raised above the LCST. It is believed that this occurs due to the change in hydrophilic interaction to the hydrophobic interaction.1 Concentration and molecular weight of PNIPAM affects the LCST by less than 1K (304???306K). Lower molecular weight samples appear to have slightly higher LCST. On the other hand, the presence of salts ions in the solution lowers the LCST significantly.1,4 > It is believed that, when PNIPAM is dissolved in solvent such as water, PNIPAM has to arrange itself in a specific orientation to form hydrogen bond with the already somewhat arranged water molecules.1 In the case of water molecules, which are near to hydrophobic group of polymer, -CH3 of the PNIPAM side chains, these water molecules must reorient being unable to form hydrogen bond with the non-polar groups in PNIPAM. This reorientation leads to formation of clathrate-like structures, this phenomenon is known as hydrophobic effect, results in decreased entropy upon mixing (negative ??S).1 When temperature is raised, the entropy term dominates the otherwise exothermic enthalpy of the hydrogen bonds formed between the polymer polar groups and water molecules that is the initial driving force for dissolution. Once the free energy change (??G) becomes positive upon mixing, the consequence is phase separation above a LCST as seen in the case of PNIPAM.1 If the concentration of th > e PNIPAM is high enough, this replacement of PNIPAM-water contacts with PNIPAM-PNIPAM and water-water contacts is manifested by precipitation.1 > In addition to the temperature???s inducing the collapse of the polymer chain, PNIPAM is insoluble in a proper mixture of water and methanol, despite both water and methanol being good solvents for PNIPAM at low temperature.1 The reentrant coil-to-globule-to-coil transition of PNIPAM takes place in a water/methanol mixture with an increase in the methanol content at room temperature. However, the mechanism of this transition is still not well established. It is believed that the transition is implicative to the solvation effect. Two potential mechanisms have been proposed. One suggested that the transition should be induced by the preferential adsorption of methanol molecules on PNIPAM. However, Theoretical calculations done by Pang et. al. demonstrate that water is as stable as methanol for staying in the vicinity of PNIPAM.5 The others ascribed it to the formation of water/methanol clusters. In addition to water/methanol clusters, pure water/water and methanol/methanol clu > sters can also be formed in their mixtures and may affect the conformational change of polymer chain. MD simulation techniques can be used to evaluate the various hydrogen bonding interactions between methanol-water and methanol-polymer and methanol-methanol and understand the lowering of LCST at atomistic level. > We plan to use MD simulation techniques to understand the role of methanol in influencing the LCST of PNIPAM at atomistic level. To carry out these MD simulations, a simulation cell with ~30-mer of PNIPAM will be solvated with a mixture of water and methanol with different molar ratios. Simulations will be carried out at 260, 278, and 310K for 40ns. The simulated MD trajectories will be used to evaluate the various structural (e.g. radius of gyration (Rg), radial distribution functions (rdf)), and transport properties of water molecules. > > Project description: Accuracy of the model and MD simulation results mainly depends upon the method of structure generation and force-field used for MD simulations.6 In this work we propose to use the Polymer consistent force field (PCFF) to understand the atomic scale role of methanol on the LCST of PNIPAM.7 The preliminary studies we carried out with PCFF on the PNIPAM-pure water systems predicted the LCST close to 305K, which is in good agreement with the experimentally observed value. A fully atomistic level polymer chain of PNIPMA with ~30 monomer units will be placed in a simulation cell with water/methanol mixtures. Solvated polymer chains will then be equilibrated using MD simulations technique. Methanol concentration will be varied from 1M to 80M. In the case of PNIPAM, our preliminary studies and results from the literature show that to observe any phase transition in these systems, simulation time length must be in the range of 30-50ns. Simulations will be con > ducted at 260, 278, and 310K for 40ns. Structural and dynamical properties will be studied for both polymer and water/methanol mixtures by analyzing trajectories of MD simulations. Transport properties of water and methanol will be studied using Einstein relation.6 The structural evolution in all the polymer and water/methanol systems will be studied and compared with each other to study the structure of water, methanol and PNIPAM 30-mer at different temperatures. > The computational requirements for the proposed study will be substantial. For the proposed calculations, to study the phase transition across the LCST simulations should be run for ~40ns. From preliminary results of the simulations, we carried out on the CNM???s cluster Carbon and observed a clear phase transition across the LCST, for polymer chains with 30 monomer units (572 atoms) in presence of 9,000 water molecules. This system with ~30,000 atoms required ~145 hrs of simulation time for 10ns on 96 cores. > In the proposed work we plan to study, PNIPAM 30-mer polymer chains in presence of different molar ratios of water/methanol mixtures. Total number of atoms in the systems we plan to study can vary from ~66,000 to ~42,000. Table 1 lists the systems we plan to study in detail. > > Table 1: System details that are planned to study > > # of PNIPAM #of water #of methanol methanol mole > monomer units molecules molecules fractions > 30 200 11000 0.018 > 30 1000 10000 0.09 > 30 2000 9000 0.18 > 30 3000 8000 0.27 > 30 5500 5500 0.5 > 30 8000 3000 0.73 > > We plan to study 6 different concentrations of water/methanol system as listed in Table 1. All the systems will be studied at 260, 278 and 310K (Total number of simulations = 6 x 3 = 18). Each simulation will be run for ~40ns (total simulation time = 18 x 40 = 720ns). > > The estimated time for this particular work to carry out the mentioned calculations would be ~800,000 core hours. > > References: > 1.H. G. Schild, Prog. Polym. Sci. 1992, 17,163-249. > 2. D. Schmaljohann, Adv. Drug Del. Rev. 2006, 58(15), 1655-1670. > 3. A.S. Hoffman, J. of Cont. Rel. 1987, 6(1), 297-305. > 4. H. Du, R. Wickramasinghe, and X. Qian, J. Phys. Chem. B 2010, 114, 16594-16604. > 5. H. Y. J. Pang and R. Cheng, Journal of Physical Chemistry B, 2010, 114, 7429 - 7438. > 6. M.P. Allen, D. J. Tildesley, Computer Simulations of Liquid, Clarendon Press, Oxford, 1987. > 7. Accelrys, Inc. Cerius2 and Discover (programs) and Discover User Guide, version 96.0/4.0.0; Molecular Simulations, Inc.: San Diego, CA, 1996. > > Project URL: > Requested allocation: 800,000 > Justification: To study the phase transition across the LCST in the case of single PNIPAM chain, simulations should be carried out for ~50ns. From preliminary results of the simulations we carried out on the CNM???s cluster Carbon, we observed a clear phase transition across the LCST, for polymer chains with 30 monomer units (572 atoms) in presence of 9,000 water molecules. This system with ~30,000 atoms required ~145 hrs of simulation time for 10ns on 96 cores. > > > The requester has used 0 hours of their initial startup project. > > In addition to approving an initial amount, please specify a Category > and Subcategory for this project. For a list of the current selection > of approved categories, please see: > > https://wiki.lcrc.anl.gov/wiki/Processes/Categories > > Once the Allocation committee has approved the project, please go to > the Project Management page to create it: > > https://accounts.lcrc.anl.gov/projects.php > > Thank You, > The LCRC Accounts System > > _______________________________________________ > allocations-admins mailing list > allocations-admins(a)lists.lcrc.anl.gov > https://lists.lcrc.anl.gov/mailman/listinfo/allocations-admins > > > ----- End forwarded message ----- > _______________________________________________ > lcrc-core mailing list > lcrc-core(a)lists.lcrc.anl.gov > https://lists.lcrc.anl.gov/mailman/listinfo/lcrc-core

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Fwd: [lcrc-core] Fwd: [LCRC Accounts] Project Request: MD_solvent_mixtures
by John J. Low 27 Jul '11

27 Jul '11

Sanket, It would be difficult to allocate 800K core-hours this fiscal year which ends this quarter. This is a large fraction of the core-hours available on Fusion until the end of the September (approximately 5M core-hours). It would be much easier to allocate 100K core-hours to this project for this quarter (until the end of September). You could request an additional 700K core-hours for next year. Would that be acceptable? Please tell us what software you will be using in this project. John J. Low Computational Scientist-STA Mathematics and Computer Science Building 240, 1.G.10 9700 South Cass Avenue Argonne National Laboratory Argonne, IL 60439. 630-252-0045 ----- Forwarded Message ----- From: "John Valdes" <valdes(a)mcs.anl.gov> To: lcrc-core(a)lcrc.anl.gov Sent: Wednesday, July 27, 2011 2:41:24 PM Subject: [lcrc-core] Fwd: [allocations-admins] [LCRC Accounts] Project Request: MD_solvent_mixtures ----- Forwarded message from accounts(a)lcrc.anl.gov ----- Date: Thu, 21 Jul 2011 13:32:47 -0500 (CDT) From: accounts(a)lcrc.anl.gov To: allocations-admins(a)lcrc.anl.gov Subject: [allocations-admins] [LCRC Accounts] Project Request: MD_solvent_mixtures Reply-To: accounts(a)lcrc.anl.gov Hello, A new project on the LCRC cluster has been requested. Please forward the information on to the LCRC Allocation sub-committee. Applicant's name: Sanket Deshmukh Applicant's institution: ANL Applicant's division: CNM Project Name: MD_solvent_mixtures Project title: Atomistic simulations to understand the effect of Water/Methanol Solvent Mixtures on the Lower Critical Solution Temperature of poly(N-isopropylacrylamide) Associated funding: Other Systems: Carbon (CNM) Science: PNIPAM is a thermo-sensitive polymer that has a lower critical solution temperature (LCST) around 305K in aqueous solution.1 As the LCST of PNIPAM is close to human body temperature, it is a serious contender for a controlled drug delivery system.2,3 Coil-to-globule transition occurs in PNIPAM when temperature is raised above the LCST. It is believed that this occurs due to the change in hydrophilic interaction to the hydrophobic interaction.1 Concentration and molecular weight of PNIPAM affects the LCST by less than 1K (304???306K). Lower molecular weight samples appear to have slightly higher LCST. On the other hand, the presence of salts ions in the solution lowers the LCST significantly.1,4 It is believed that, when PNIPAM is dissolved in solvent such as water, PNIPAM has to arrange itself in a specific orientation to form hydrogen bond with the already somewhat arranged water molecules.1 In the case of water molecules, which are near to hydrophobic group of polymer, -CH3 of the PNIPAM side chains, these water molecules must reorient being unable to form hydrogen bond with the non-polar groups in PNIPAM. This reorientation leads to formation of clathrate-like structures, this phenomenon is known as hydrophobic effect, results in decreased entropy upon mixing (negative ??S).1 When temperature is raised, the entropy term dominates the otherwise exothermic enthalpy of the hydrogen bonds formed between the polymer polar groups and water molecules that is the initial driving force for dissolution. Once the free energy change (??G) becomes positive upon mixing, the consequence is phase separation above a LCST as seen in the case of PNIPAM.1 If the concentration of th e PNIPAM is high enough, this replacement of PNIPAM-water contacts with PNIPAM-PNIPAM and water-water contacts is manifested by precipitation.1 In addition to the temperature???s inducing the collapse of the polymer chain, PNIPAM is insoluble in a proper mixture of water and methanol, despite both water and methanol being good solvents for PNIPAM at low temperature.1 The reentrant coil-to-globule-to-coil transition of PNIPAM takes place in a water/methanol mixture with an increase in the methanol content at room temperature. However, the mechanism of this transition is still not well established. It is believed that the transition is implicative to the solvation effect. Two potential mechanisms have been proposed. One suggested that the transition should be induced by the preferential adsorption of methanol molecules on PNIPAM. However, Theoretical calculations done by Pang et. al. demonstrate that water is as stable as methanol for staying in the vicinity of PNIPAM.5 The others ascribed it to the formation of water/methanol clusters. In addition to water/methanol clusters, pure water/water and methanol/methanol clu sters can also be formed in their mixtures and may affect the conformational change of polymer chain. MD simulation techniques can be used to evaluate the various hydrogen bonding interactions between methanol-water and methanol-polymer and methanol-methanol and understand the lowering of LCST at atomistic level. We plan to use MD simulation techniques to understand the role of methanol in influencing the LCST of PNIPAM at atomistic level. To carry out these MD simulations, a simulation cell with ~30-mer of PNIPAM will be solvated with a mixture of water and methanol with different molar ratios. Simulations will be carried out at 260, 278, and 310K for 40ns. The simulated MD trajectories will be used to evaluate the various structural (e.g. radius of gyration (Rg), radial distribution functions (rdf)), and transport properties of water molecules. Project description: Accuracy of the model and MD simulation results mainly depends upon the method of structure generation and force-field used for MD simulations.6 In this work we propose to use the Polymer consistent force field (PCFF) to understand the atomic scale role of methanol on the LCST of PNIPAM.7 The preliminary studies we carried out with PCFF on the PNIPAM-pure water systems predicted the LCST close to 305K, which is in good agreement with the experimentally observed value. A fully atomistic level polymer chain of PNIPMA with ~30 monomer units will be placed in a simulation cell with water/methanol mixtures. Solvated polymer chains will then be equilibrated using MD simulations technique. Methanol concentration will be varied from 1M to 80M. In the case of PNIPAM, our preliminary studies and results from the literature show that to observe any phase transition in these systems, simulation time length must be in the range of 30-50ns. Simulations will be con ducted at 260, 278, and 310K for 40ns. Structural and dynamical properties will be studied for both polymer and water/methanol mixtures by analyzing trajectories of MD simulations. Transport properties of water and methanol will be studied using Einstein relation.6 The structural evolution in all the polymer and water/methanol systems will be studied and compared with each other to study the structure of water, methanol and PNIPAM 30-mer at different temperatures. The computational requirements for the proposed study will be substantial. For the proposed calculations, to study the phase transition across the LCST simulations should be run for ~40ns. From preliminary results of the simulations, we carried out on the CNM???s cluster Carbon and observed a clear phase transition across the LCST, for polymer chains with 30 monomer units (572 atoms) in presence of 9,000 water molecules. This system with ~30,000 atoms required ~145 hrs of simulation time for 10ns on 96 cores. In the proposed work we plan to study, PNIPAM 30-mer polymer chains in presence of different molar ratios of water/methanol mixtures. Total number of atoms in the systems we plan to study can vary from ~66,000 to ~42,000. Table 1 lists the systems we plan to study in detail. Table 1: System details that are planned to study # of PNIPAM #of water #of methanol methanol mole monomer units molecules molecules fractions 30 200 11000 0.018 30 1000 10000 0.09 30 2000 9000 0.18 30 3000 8000 0.27 30 5500 5500 0.5 30 8000 3000 0.73 We plan to study 6 different concentrations of water/methanol system as listed in Table 1. All the systems will be studied at 260, 278 and 310K (Total number of simulations = 6 x 3 = 18). Each simulation will be run for ~40ns (total simulation time = 18 x 40 = 720ns). The estimated time for this particular work to carry out the mentioned calculations would be ~800,000 core hours. References: 1.H. G. Schild, Prog. Polym. Sci. 1992, 17,163-249. 2. D. Schmaljohann, Adv. Drug Del. Rev. 2006, 58(15), 1655-1670. 3. A.S. Hoffman, J. of Cont. Rel. 1987, 6(1), 297-305. 4. H. Du, R. Wickramasinghe, and X. Qian, J. Phys. Chem. B 2010, 114, 16594-16604. 5. H. Y. J. Pang and R. Cheng, Journal of Physical Chemistry B, 2010, 114, 7429 - 7438. 6. M.P. Allen, D. J. Tildesley, Computer Simulations of Liquid, Clarendon Press, Oxford, 1987. 7. Accelrys, Inc. Cerius2 and Discover (programs) and Discover User Guide, version 96.0/4.0.0; Molecular Simulations, Inc.: San Diego, CA, 1996. Project URL: Requested allocation: 800,000 Justification: To study the phase transition across the LCST in the case of single PNIPAM chain, simulations should be carried out for ~50ns. From preliminary results of the simulations we carried out on the CNM???s cluster Carbon, we observed a clear phase transition across the LCST, for polymer chains with 30 monomer units (572 atoms) in presence of 9,000 water molecules. This system with ~30,000 atoms required ~145 hrs of simulation time for 10ns on 96 cores. The requester has used 0 hours of their initial startup project. In addition to approving an initial amount, please specify a Category and Subcategory for this project. For a list of the current selection of approved categories, please see: https://wiki.lcrc.anl.gov/wiki/Processes/Categories Once the Allocation committee has approved the project, please go to the Project Management page to create it: https://accounts.lcrc.anl.gov/projects.php Thank You, The LCRC Accounts System _______________________________________________ allocations-admins mailing list allocations-admins(a)lists.lcrc.anl.gov https://lists.lcrc.anl.gov/mailman/listinfo/allocations-admins ----- End forwarded message ----- _______________________________________________ lcrc-core mailing list lcrc-core(a)lists.lcrc.anl.gov https://lists.lcrc.anl.gov/mailman/listinfo/lcrc-core

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[LCRC Accounts] Project Allocation Request
by accounts＠lcrc.anl.gov 26 Jul '11

26 Jul '11

Hello, A change in allocation has been requested: Requester: sdeshmuk (Sanket Deshmukh) Project: MD_of_pnipam_brush Title: Structural and dynamic properties of thermo-sensitive polymer brushes: Molecular Dynamics study. Description: In this work we propose to use the Consistent Valence force field (CVFF) to understand the structural changes in the polymer brush at global as well as local level using an atomistic level model. The preliminary studies we carried out with CVFF on a single chain made up of 30 monomer units of PNIPAM in presence of pure water predicted the LCST close to 305K, which is in good agreement with experimentally observed value. To carry out MD simulations we will be using LAMMPS MD simulation package. Fully atomistic polymer chains with ~25 monomer units will be generated. Each chain will be end-grafted to form a 5 x 5 grid on flat surface, which will define the x-y plane of the system. Grafting density will be varied from 0.05 to 0.5 to study the structural changes with respect to grafting density. Depending upon the number of polymer chains TIP4P water molecules (~20,000 to ~100,000) will be added to simulation cell. To study the structural changes across the LCST o f PNIPAM, simulation system will then be equilibrated up to 40-50ns using LAMMPS at 278, 310 and 360K. To study the change in the LCST of PNIPAM in presence of another thermo-sensitive polymer, if any, we propose to use PNIPAM and PEO grafted and equilibrated in similar manner as mentioned above. The computational requirements for the proposed study will be substantial. To study the phase transition across the LCST in the case of single PNIPAM chain, simulations should be carried out for ~50ns. From preliminary results of the simulations we carried out on the CNM’s cluster Carbon, we observed a clear phase transition across the LCST, for polymer chains with 30 monomer units (572 atoms) in presence of 9,000 water molecules. This system with ~30,000 atoms required ~145 hrs of simulation time for 10ns on 96 cores. In the proposed work we plan to study, PNIPAM ~25 mer (475 atoms) brush made up of ~20 polymer chains (~9000 atoms) in presence of ~30,000 water molecules. Simulations will be carried out at 278, 310 and 360K for ~50ns (total simulation time = 150ns). We also propose to study PNIPAM ~25 mer (475 atoms) and PEO ~25 mer (150 atoms) polymer chains. In the initial stages of this project we plan to use 5 and 10 chains of both PNIPAM (2375 and 4750 atoms) and PEO (1500 and 3000 atoms) in presence of 30,000 water molecules. Total system will be consisted of ~100,000 atoms and simulations will be carried out at 278, 310 and 360K for ~50ns (total simulation time = 300ns). The estimated time to carry out the mentioned calculations in this particular work would be ~500,000 core hours. Current: undetermined amount Justification: To study the phase transition across the LCST in the case of single PNIPAM chain, simulations should be carried out for ~50ns. From preliminary results of the simulations we carried out on the CNM’s cluster Carbon, we observed a clear phase transition across the LCST, for polymer chains with 30 monomer units (572 atoms) in presence of 9,000 water molecules. This system with ~30,000 atoms required ~145 hrs of simulation time for 10ns on 96 cores. Requested: 500000 A specific reason has been given: I have already used the allocated time (450000 + 225000) for my calculations. I have finished the first step proposed in this proposal. Currently, I am conducting the simulations of polymer brush structures of PNIPAM and PEG. To carry out these simulations with different molecular weights of PNIPAM and PEG and with different grafting density I need more computational time. Based on the calculations I already carried out on Fusion, estimated time for these calculations would be around 500000 core-hours. This needs to be approved and the final allocation amount decided upon. Thank You, The LCRC Accounts System

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[LCRC Accounts] Project Allocation Request
by accounts＠lcrc.anl.gov 26 Jul '11

26 Jul '11

Hello, A change in allocation has been requested: Requester: tmunson (Todd Munson) Project: TAO Title: Toolkit for Advanced Optimization Description: The Toolkit for Advanced optimization (TAO) focuses on the development of algorithms and software for the solution of large-scale optimization problems on high-performance architectures. Areas of interest include nonlineare least squares, unconstrained and bound constrained optimization, and optimization problems with partial differential equation constraints. One reason that the TAO group uses the LCRC is to benchmark parallel optimization solvers in TAO. Many of the results generated will be published in journal and reports, so we like to use machines with fast processors and fast connections between them. Since portability of software is also a priority of TAO, Fusion provides us with another architecture to test our solvers. The developers of TAO and their collaborators also wish to use the LCRC for their applications. These applications involve several computational toolkits developed within DOE and require extensive computational resources. Current: undetermined amount Justification: Requested: 50000 A specific reason has been given: This allocation is to perform scalability studies with a summer student on our new PDE-constrained optimization solver. This needs to be approved and the final allocation amount decided upon. Thank You, The LCRC Accounts System

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[LCRC Accounts] Project Request: MD_solvent_mixtures
by accounts＠lcrc.anl.gov 21 Jul '11

21 Jul '11

Hello, A new project on the LCRC cluster has been requested. Please forward the information on to the LCRC Allocation sub-committee. Applicant's name: Sanket Deshmukh Applicant's institution: ANL Applicant's division: CNM Project Name: MD_solvent_mixtures Project title: Atomistic simulations to understand the effect of Water/Methanol Solvent Mixtures on the Lower Critical Solution Temperature of poly(N-isopropylacrylamide) Associated funding: Other Systems: Carbon (CNM) Science: PNIPAM is a thermo-sensitive polymer that has a lower critical solution temperature (LCST) around 305K in aqueous solution.1 As the LCST of PNIPAM is close to human body temperature, it is a serious contender for a controlled drug delivery system.2,3 Coil-to-globule transition occurs in PNIPAM when temperature is raised above the LCST. It is believed that this occurs due to the change in hydrophilic interaction to the hydrophobic interaction.1 Concentration and molecular weight of PNIPAM affects the LCST by less than 1K (304–306K). Lower molecular weight samples appear to have slightly higher LCST. On the other hand, the presence of salts ions in the solution lowers the LCST significantly.1,4 It is believed that, when PNIPAM is dissolved in solvent such as water, PNIPAM has to arrange itself in a specific orientation to form hydrogen bond with the already somewhat arranged water molecules.1 In the case of water molecules, which are near to hydrophobic group of polymer, -CH3 of the PNIPAM side chains, these water molecules must reorient being unable to form hydrogen bond with the non-polar groups in PNIPAM. This reorientation leads to formation of clathrate-like structures, this phenomenon is known as hydrophobic effect, results in decreased entropy upon mixing (negative ΔS).1 When temperature is raised, the entropy term dominates the otherwise exothermic enthalpy of the hydrogen bonds formed between the polymer polar groups and water molecules that is the initial driving force for dissolution. Once the free energy change (ΔG) becomes positive upon mixing, the consequence is phase separation above a LCST as seen in the case of PNIPAM.1 If the concentration of th e PNIPAM is high enough, this replacement of PNIPAM-water contacts with PNIPAM-PNIPAM and water-water contacts is manifested by precipitation.1 In addition to the temperature’s inducing the collapse of the polymer chain, PNIPAM is insoluble in a proper mixture of water and methanol, despite both water and methanol being good solvents for PNIPAM at low temperature.1 The reentrant coil-to-globule-to-coil transition of PNIPAM takes place in a water/methanol mixture with an increase in the methanol content at room temperature. However, the mechanism of this transition is still not well established. It is believed that the transition is implicative to the solvation effect. Two potential mechanisms have been proposed. One suggested that the transition should be induced by the preferential adsorption of methanol molecules on PNIPAM. However, Theoretical calculations done by Pang et. al. demonstrate that water is as stable as methanol for staying in the vicinity of PNIPAM.5 The others ascribed it to the formation of water/methanol clusters. In addition to water/methanol clusters, pure water/water and methanol/methanol clu sters can also be formed in their mixtures and may affect the conformational change of polymer chain. MD simulation techniques can be used to evaluate the various hydrogen bonding interactions between methanol-water and methanol-polymer and methanol-methanol and understand the lowering of LCST at atomistic level. We plan to use MD simulation techniques to understand the role of methanol in influencing the LCST of PNIPAM at atomistic level. To carry out these MD simulations, a simulation cell with ~30-mer of PNIPAM will be solvated with a mixture of water and methanol with different molar ratios. Simulations will be carried out at 260, 278, and 310K for 40ns. The simulated MD trajectories will be used to evaluate the various structural (e.g. radius of gyration (Rg), radial distribution functions (rdf)), and transport properties of water molecules. Project description: Accuracy of the model and MD simulation results mainly depends upon the method of structure generation and force-field used for MD simulations.6 In this work we propose to use the Polymer consistent force field (PCFF) to understand the atomic scale role of methanol on the LCST of PNIPAM.7 The preliminary studies we carried out with PCFF on the PNIPAM-pure water systems predicted the LCST close to 305K, which is in good agreement with the experimentally observed value. A fully atomistic level polymer chain of PNIPMA with ~30 monomer units will be placed in a simulation cell with water/methanol mixtures. Solvated polymer chains will then be equilibrated using MD simulations technique. Methanol concentration will be varied from 1M to 80M. In the case of PNIPAM, our preliminary studies and results from the literature show that to observe any phase transition in these systems, simulation time length must be in the range of 30-50ns. Simulations will be con ducted at 260, 278, and 310K for 40ns. Structural and dynamical properties will be studied for both polymer and water/methanol mixtures by analyzing trajectories of MD simulations. Transport properties of water and methanol will be studied using Einstein relation.6 The structural evolution in all the polymer and water/methanol systems will be studied and compared with each other to study the structure of water, methanol and PNIPAM 30-mer at different temperatures. The computational requirements for the proposed study will be substantial. For the proposed calculations, to study the phase transition across the LCST simulations should be run for ~40ns. From preliminary results of the simulations, we carried out on the CNM’s cluster Carbon and observed a clear phase transition across the LCST, for polymer chains with 30 monomer units (572 atoms) in presence of 9,000 water molecules. This system with ~30,000 atoms required ~145 hrs of simulation time for 10ns on 96 cores. In the proposed work we plan to study, PNIPAM 30-mer polymer chains in presence of different molar ratios of water/methanol mixtures. Total number of atoms in the systems we plan to study can vary from ~66,000 to ~42,000. Table 1 lists the systems we plan to study in detail. Table 1: System details that are planned to study # of PNIPAM #of water #of methanol methanol mole monomer units molecules molecules fractions 30 200 11000 0.018 30 1000 10000 0.09 30 2000 9000 0.18 30 3000 8000 0.27 30 5500 5500 0.5 30 8000 3000 0.73 We plan to study 6 different concentrations of water/methanol system as listed in Table 1. All the systems will be studied at 260, 278 and 310K (Total number of simulations = 6 x 3 = 18). Each simulation will be run for ~40ns (total simulation time = 18 x 40 = 720ns). The estimated time for this particular work to carry out the mentioned calculations would be ~800,000 core hours. References: 1.H. G. Schild, Prog. Polym. Sci. 1992, 17,163-249. 2. D. Schmaljohann, Adv. Drug Del. Rev. 2006, 58(15), 1655-1670. 3. A.S. Hoffman, J. of Cont. Rel. 1987, 6(1), 297-305. 4. H. Du, R. Wickramasinghe, and X. Qian, J. Phys. Chem. B 2010, 114, 16594-16604. 5. H. Y. J. Pang and R. Cheng, Journal of Physical Chemistry B, 2010, 114, 7429 - 7438. 6. M.P. Allen, D. J. Tildesley, Computer Simulations of Liquid, Clarendon Press, Oxford, 1987. 7. Accelrys, Inc. Cerius2 and Discover (programs) and Discover User Guide, version 96.0/4.0.0; Molecular Simulations, Inc.: San Diego, CA, 1996. Project URL: Requested allocation: 800,000 Justification: To study the phase transition across the LCST in the case of single PNIPAM chain, simulations should be carried out for ~50ns. From preliminary results of the simulations we carried out on the CNM’s cluster Carbon, we observed a clear phase transition across the LCST, for polymer chains with 30 monomer units (572 atoms) in presence of 9,000 water molecules. This system with ~30,000 atoms required ~145 hrs of simulation time for 10ns on 96 cores. The requester has used 0 hours of their initial startup project. In addition to approving an initial amount, please specify a Category and Subcategory for this project. For a list of the current selection of approved categories, please see: https://wiki.lcrc.anl.gov/wiki/Processes/Categories Once the Allocation committee has approved the project, please go to the Project Management page to create it: https://accounts.lcrc.anl.gov/projects.php Thank You, The LCRC Accounts System

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Re: [allocations-admins] Project Allocation Request - Lattice-QCD
by Bair, Raymond A. 20 Jul '11

20 Jul '11

Dear Don, At the June 28th Allocations Committee meeting, the committee considered your previous request (and other people's requests) in light of available resources in the fourth quarter and they added 125,000 hours. Regards, Ray On 6/30/11 11:48 AM, "accounts(a)lcrc.anl.gov" <accounts(a)lcrc.anl.gov> wrote: > Hello, > > A change in allocation has been requested: > > Requester: sinclair (Donald Sinclair) > Project: Lattice-QCD > Title: Lattice simulations of Conformal and Walking > Technicolor. > Description: We perform simulations to evaluate the functional integrals of > QCD-like theories formulated on a discrete space-time lattice to enable > determination of the non-perturbative aspects these theories. These include > the properties of these theories at non-zero temperature including the scales > of confinement and chiral symmetry breaking, and such zero temperature > properties as spectra, decay constants and the running of the gauge coupling > constant. We are particularly interested in those theories where the coupling > constant evolves particularly slowly, since these are candidate 'Walking > Technicolor' theories. Related to these are theories with an infrared fixed > point. Of special interest is to differentiate these two different types of > behaviour. > > We are performing simulations of QCD-like theories which are models for > Walking or Conformal Technicolor. We have been studying theories which are > essentially QCD but with colour-sextet rather than colour-triplet quarks. We > hope to measure the running of the QCD coupling constant. For 2 or 3 flavours, > 2-loop perturbation theory predicts an infrared fixed point. For 2 flavours, > it is possible that a chiral condensate forms before this fixed point is > reached. If so the fixed point is avoided, the theory is confining and chiral > symmetry breaks spontaneously. However, there is a region where the coupling > constant evolves very slowly. These are the properties required for a walking > technicolor theory. Simulations we have performed so far at finite temperature > suggest that this theory does indeed walk. This is an ongoing program at > NERSC. We wish to run small-lattice simulations of the 3-flavour theory, which > we expect to have conformal, rather than walking behaviour on Fusion, for > comparison. If we are correct, the properties of the 2 and 3 flavour > theories should look rather different. > > Our sextet quark codes are based on our earlier triplet quark codes and use > the RHMC simulation method. The Rational Hybrid Monte Carlo (RHMC) is a > stochastic molecular dynamics algorithm. The functional integral of QCD is > written as a partition function of a classical field theory evolving in a > fictitious time. The determinant of the Dirac operator raised to a fractional > power is calculated by introducing bosonic fields (pseudofermions), and > sandwiching this Dirac operator raised to minus said fractional power between > them. This fractional power of the Dirac operator is approximated to machine > accuracy by a rational approximation. After defining this this theory on a > discrete space-time lattice, the inversions required by the partial-fraction > expansion of the rational approximation are performed using Krylov space > methods, in particular a multi-shift extension of the conjugate gradient > algorithm. A global Metropolis Monte-Carlo accept/reject step applied at the > end of each t > rajectory removes discretization errors introduced by the numerical > integration of these stochastic equations of motion. We parallelize the code > by assigning a fixed number of adjacent lattice sites to each MPI task. > Network bandwidth ultimately limits how small a chunk of the lattice can be > assigned to each task. > > Benchmarks of this code on Fusion for the 24^3*12 lattice planned for > some of our FY2011 runs give: > 24 cores = 46 Gflops > 48 cores = 95 Gflops > 72 cores = 148 Gflops > 96 cores = 220 Gflops > 144 cores = 369 Gflops > 288 cores = 784 Gflops > We plan to run the 24^3*12 lattice jobs on 288 cores (36 nodes). Our smaller > lattice 16^3*8 runs would be run on 128 cores (16 nodes). > > Current: undetermined amount > Justification: This allocation request is based on having one 288 core job or > two 128 core jobs running at all times. Our project is expected to use time at > NERSC and NICS as well. LCRC has the advantage that it provides facilities for > jobs which have medium levels of parallelism such as the 128 and 288 core jobs > indicated here, which are discriminated against on larger machines such as > Franklin and Hopper(stage 2) at NERSC, and Kraken at NICS. Carver at NERSC > provides a similar platform to Fusion, but the large number of users and > potential users mean that we cannot rely on it to provide the bulk of our > computing at NERSC. Numbers given in the description section indicate that > scaling is excellent. We have plans to increase the level of parallelism for > this code, but this is probably irrelevant to our Fusion use. > For codes which have smaller portions of the lattice on each core, such as our > 16^3*8 code, performances of around 3 Gflop/core are sustained. > > Requested: 500000 > > A specific reason has been given: > To complete 24^3*8 lattice runs at m=0.0025, beta=6.7, needed to determine if > runs on 16^3*8 lattice suffer from finite volume effects. Current allocation > is exhausted. > > This needs to be approved and the final allocation amount decided upon. > > Thank You, > The LCRC Accounts System > _______________________________________________ > allocations-admins mailing list > allocations-admins(a)lists.lcrc.anl.gov > https://lists.lcrc.anl.gov/mailman/listinfo/allocations-admins ----------------------------------------- Ray Bair Computing, Environment, and Life Sciences Argonne National Laboratory and the University of Chicago TCS Building 240, Room 4126 9700 South Cass Avenue Argonne, IL 60439 email: rbair(at)anl.gov Phone: (630)252-5751

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FW: [LCRC Accounts] Project Allocation Request
by Bair, Raymond A. 20 Jul '11

20 Jul '11

------ Forwarded Message From: Benoit Roux <roux.uchicago(a)gmail.com> Date: Wed, 20 Jul 2011 13:58:06 -0500 To: Raymond Bair <rbair(a)anl.gov> Subject: Re: [allocations-admins] [LCRC Accounts] Project Allocation Request Sorry, I put 1,000,000 because I did not know how long is the period to cover. For the NachBAC sodium-selective channel computations, here is what we absolute need starting right now: Equilibration of the initial system NAMD benchmark: 5.2 hour/ns with 16 nodes (128 cores) TOTAL NEEDED: (128 cores) * (5.2 hours/ns) * (50 ns) = 33,280 SUs Umbrella sampling hamiltonian replica-exchange molecular dynamics (US/H-REMD) CHARMM/REPDSTR benchmark: 50 hours/ns with 1 node (8 cores) per replica TOTAL NEEDED: (60 replica) * (8 cores) * (50 hours/ns) * (10 ns) = 240,000 SUs Grand Total needed: 280,000 SUs On Jul 19, 2011, at 5:52 PM, Bair, Raymond A. wrote: > Hi Benoit, > > How many hours does this project need between now and Sept. 30, 2011? > 1,000,000? > > Ray > > ------ End of Forwarded Message

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[LCRC Accounts] Project Allocation Request
by accounts＠lcrc.anl.gov 19 Jul '11

19 Jul '11

Hello, A change in allocation has been requested: Requester: roux (Benoit Roux) Project: kcsa Title: Computational study of ion selectivity in the KcsA channel Description: Understanding quantitatively the microscopic factors controlling ion selectivity remains a great challenge. In simple terms, the concept of selectivity means that the "correct" ion, is able to binding more favorably than an "incorrect" ion. At a physical level, it is to be anticipated that energetics and solvation play a key role in this process, although different aspects of energetics may be highlighted by the various experimental methods used to probe the system. Some experimental measurements are more sensitive to the relative depth of free energy wells, while others are more sensitive to the relative height of free energy barriers. In the case of ion channels, the large hydration energy of the ions contrasts with the small free energy barriers necessary for the fast conduction observed experimentally. This implies that ion-protein association is ultimately controlled by a delicate balance of very strong interactions. Frequently, permeation involves th e partial dehydration of an ion, followed by the binding to a proteinaceous environment. This archetype is well illustrated by the crystal structure of the KcsA channel. The pore of the KcsA channel comprises a wide aqueous vestibular entryway, lined by non-polar residues on the intracellular side, leading up on the extracellular side to a narrow region lined by backbone carbonyl oxygens. This region of the pore, formed by the residues corresponding to the signature sequence TTVGYG common to all K+ channels, acts as a "selectivity filter" by allowing only the passage of nearly dehydrated K+ ions across the cell membrane. In such narrow molecular pores, a permeating ion must shed most of its surrounding water molecules and the large energetic loss due to dehydration must be compensated by coordination with the backbone carbonyl oxygens. The most informative strategy to address such issues is to compute the multi-ion PMF corresponding to the microscopic process in question (Berneche and Roux, Nature 2001). In particular, the calculation of the PMF enables us to pin-point the location of the largest barrier opposing the passage of a single Na+ ion while there are two K+ ions elsewhere in the pore. We carry those type of calculations using umbrella sampling MD simulations. Another strategy is free energy perturbation (FEP), which allows to compute the relative free energy of different ions at precise location in the pore. There are 2 sub-projects: 1) Compute the multi-ion PM for Na+ permeation through the KcsA channel using the open state structure that was recently determined by X-ray crystallography in the Perozo laboratory. We have already done a similar calculation for the KcsA in the closed state (Egwolf and Roux, JMB 2010). Umbrella sampling MD simulations are used to obtain W(z1,z2,z3) the 3-ion PMF function of the coordinate of the 3 ions in the selectivity filter. To understand the effect of selectivity, two systems must be considered: with 3 K+ ions, and with 1 Na+ and 2 K+ ions. Based on our experience with similar computations, we know that a grand total of 3931 MD window simulations is needed for two systems. Each window should be simulated for 0.6 ns, the first 0.1 ns being used for equilibration and the last 0.5 ns for sampling proper, for total aggregate MD simulation time of 2.4 microseconds for each of the two systems. The unbiased 3D PMFs are then calculated using the weighted histogram method ( WHAM). The simulations are generated with NAMD, which is the most efficient program for classical MD. 2) Use FEP to compute the relative free energy of Na+ and K+ in a KcsA pore with DFT/MM simulations. For this computation we are using CHARMM combined with the DFT program DEMON (developed by Denys Salahub in Calgary). This enables us to treat the ions and the nearby protein atoms with DFT and the remainder with the force field of molecular dynamics. Software requirements NAMD, CHARMM, DEMON Expected number of project members: Benoit Roux, David Medovoy (multi-ion PMF calculation) and Chris Rowley (selectivity with density function theory and MD force field) REFERENCES Noskov, SY; Berneche, S; Roux, B Control of ion selectivity in potassium channels by electrostatic and dynamic properties of carbonyl ligands. NATURE Volume: 431 Issue: 7010 Pages: 830-834 Published: OCT 14 2004 Egwolf, B; Roux, B Ion Selectivity of the KcsA Channel: A Perspective from Multi-Ion Free Energy Landscapes. JOURNAL OF MOLECULAR BIOLOGY Volume: 401 Issue: 5 Pages: 831-842 Published: 2010 Current: undetermined amount Justification: The umbrella sampling calculations described here constitute a major part of the PhD thesis of David Medovoy, a graduate student in Biophysics at the University of Chicago. The total requested allocation for this project is: 500,000 SU = (3931 windows) * (0.6 ns/window) * ((8*cores)*(12 hour)/ns). The planned FEP simulations for with DFT/MM will be carried out by Chris Rowley, a postdoc in the lab who has a fellowship from the Canadian NSERC. His work will be a new attack on the problem. Never before has someone computed relative free energies in those channels with DFT/MM. We anticipate this those FEP calculations will require about 500,000 SUs during the year. Demon scales up to about 64 processors, but we are investigating the dependencies on grid density (in DFT) to see how it affects the performance. Requested: 1000000 A specific reason has been given: For the first time, a new xray structure of a sodium selective channel just appeared. We knew this was coming. We urgently need some SUs to start this competitive project right away. This needs to be approved and the final allocation amount decided upon. Thank You, The LCRC Accounts System

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