Academic literature on the topic 'Compound follow-on tool'
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Journal articles on the topic "Compound follow-on tool"
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Nakaminami, Masamitsu, Tsutomu Tokuma, Kazuhiko Matsumoto, Sachinori Sakashita, Toshimichi Moriwaki, and Keiichi Nakamoto. "Optimal Structure Design Methodology for Compound Multiaxis Machine Tools - II - Investigation of Basic Structure -." International Journal of Automation Technology 1, no. 2 (November 5, 2007): 87–93. http://dx.doi.org/10.20965/ijat.2007.p0087.
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Compound multiaxis machine tools are used to machine high-value-added parts through integrating milling and turning. Compound machine tools are generally structured based on a conventional NC lathe by incorporating Y axis and automatic tool changer (ATC) components for milling. Due to complexity of the structure and functional versatility required for a compound machine tool, accuracy, productivity, and return on investment (ROI) must be improved over conventional NC lathes and machining centers. In the sections that follow, we discuss design methodology for compound multiaxis machine tools, focusing on the design of an optimal basic structure for high accuracy and high productivity. We propose a box in box structure, a movable column-Y axis, and a boring machine structure. We analyzed static rigidity, dynamic features, and movement accuracy of machine structures theoretically using FEM for three proposed structures. We found that the box in box structure is suitable for compound multiaxis machine tools to achieve high accuracy and high productivity.
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Sun, Xing Wei, Wan Tao Liu, You Jun Zhang, and Ke Wang. "The Influence of Following Error of Servo System on Machining Precision for NC Machine Tool." Advanced Materials Research 118-120 (June 2010): 841–45. http://dx.doi.org/10.4028/www.scientific.net/amr.118-120.841.
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The characteristic of servo system is an important data to influence the mechanical working properties of NC machine tool. In this paper, based on servo system characteristic, the cause of following error has been studied. It discussed the effect on machining precision of following error on part contour when machining circular contour. Then some calculation equations have been worked out. In order to reduce the following error, the method of compound control has been advanced in the last, and it has been proved to be a feasible way to reduce the influence of follow error on machining contour of NC machine tool.
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Scholle, Michael D., Doug McLaughlin, and Zachary A. Gurard-Levin. "High-Throughput Affinity Selection Mass Spectrometry Using SAMDI-MS to Identify Small-Molecule Binders of the Human Rhinovirus 3C Protease." SLAS DISCOVERY: Advancing the Science of Drug Discovery 26, no. 8 (June 19, 2021): 974–83. http://dx.doi.org/10.1177/24725552211023211.
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Affinity selection mass spectrometry (ASMS) has emerged as a powerful high-throughput screening tool used in drug discovery to identify novel ligands against therapeutic targets. This report describes the first high-throughput screen using a novel self-assembled monolayer desorption ionization (SAMDI)–ASMS methodology to reveal ligands for the human rhinovirus 3C (HRV3C) protease. The approach combines self-assembled monolayers of alkanethiolates on gold with matrix-assisted laser desorption ionization time-of-flight (MALDI TOF) mass spectrometry (MS), a technique termed SAMDI-ASMS. The primary screen of more than 100,000 compounds in pools of 8 compounds per well was completed in less than 8 h, and informs on the binding potential and selectivity of each compound. Initial hits were confirmed in follow-up SAMDI-ASMS experiments in single-concentration and dose–response curves. The ligands identified by SAMDI-ASMS were further validated using differential scanning fluorimetry (DSF) and in functional protease assays against HRV3C and the related SARS-CoV-2 3CLpro enzyme. SAMDI-ASMS offers key benefits for drug discovery over traditional ASMS approaches, including the high-throughput workflow and readout, minimizing compound misbehavior by using smaller compound pools, and up to a 50-fold reduction in reagent consumption. The flexibility of this novel technology opens avenues for high-throughput ASMS assays of any target, thereby accelerating drug discovery for diverse diseases.
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Wazir, Sarah, Mirko M. Maksimainen, Heli I. Alanen, Albert Galera-Prat, and Lari Lehtiö. "Activity-Based Screening Assay for Mono-ADP-Ribosylhydrolases." SLAS DISCOVERY: Advancing the Science of Drug Discovery 26, no. 1 (June 12, 2020): 67–76. http://dx.doi.org/10.1177/2472555220928911.
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ADP-ribosylation is a post-translational modification involved in the regulation of many vital cellular processes. This posttranslational modification is carried out by ADP-ribosyltransferases converting β-NAD+ into nicotinamide and a protein-linked ADP-ribosyl group or a chain of PAR. The reverse reaction, release of ADP-ribose from the acceptor molecule, is catalyzed by ADP-ribosylhydrolases. Several hydrolases contain a macrodomain fold, and activities of human macrodomain protein modules vary from reading or erasing mono- and poly-ADP-ribosylation. Macrodomains have been linked to diseases such as cancer, making them potential drug targets. Discovery of inhibitors requires robust biochemical tools mostly lacking for hydrolases, and here we describe an inhibitor screening assay against mono-ADP-ribosylhydrolyzing enzymes. The activity-based assay uses an α-NAD+, anomer of β-NAD+, which is accepted as a substrate by MacroD1, MacroD2, and ARH3 due to its resemblance to the protein-linked ADP-ribose. The amount of α-NAD+ present after hydrolysis is measured by chemically converting it on a microtiter plate to a fluorescent compound. We optimized the assay for MacroD2 and performed a proof-of-concept compound screening. Three compounds were identified as screening hits with micromolar potency. However, further characterization of the compounds identified them as protein destabilizers, excluding further follow-up studies. Validation and screening demonstrated the usability of the in vitro assay for MacroD2, and we also demonstrate the applicability of the assay as a tool for other human ADP-ribosylhydrolases.
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Pa, Pai Shan. "Design of Surface Finish Using Compound Processes of Grinding and Electrochemical Finishing Following Turning." Key Engineering Materials 373-374 (March 2008): 782–85. http://dx.doi.org/10.4028/www.scientific.net/kem.373-374.782.
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A new finish method uses an effective electrode connecting with a nonconductive grinding tool to execute the design of compound processes of electrochemical finishing and grinding following turning is investigated. The submitted processes can be used for various turning operations. Through simple equipment attachment, electrochemical finishing and grinding can follow to execute the finishing process on the same machine. Among the factors affecting electrochemical finishing the performance of grinding combined with electrochemical finishing is primarily discussed. In the experiment, the electrode is used with continuous and pulsed direct current. The grinding tool moves following the electrode and grinds the workpiece surface. The experimental parameters are electrical current rating, feed rate of electrode and grinding tool, rotational speed of workpiecel, pulsed period, and geometry of finish-tool. The results show that pulsed direct current with longer off-time can slightly improve the finish effect for its dregs discharge mobility. Using an adequate rotational speed of workpiece with high rotational speed is advantageous to the finish effect. A thinner plate-form electrode with a smaller end radius is associated with larger discharge space and produces higher current density and provides faster feed rate and a better finish effect. The grinding can effectively increase the finish effect. An effective and a low-cost finish process through the design electrode and using the grinding assistance in the electrochemical finishing after turning process make the surface of workpiece smooth and bright.
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Iqbal, Zarina, and Saima Sadaf. "Sitagliptin (Januvia) patent litigation: Another link in the judicial train of ‘Proactive Infringement’ of patented rights in developing countries." Journal of Generic Medicines: The Business Journal for the Generic Medicines Sector 16, no. 2 (March 29, 2020): 64–71. http://dx.doi.org/10.1177/1741134320912776.
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Driven by increasing instances of successful ‘at-risk’ launch of patented drugs in America and Europe, the strategy of using ‘proactive infringement’ as a legal tool is now getting-in, in developing countries. The rationale behind launch-at-risk is to counterbalance the innovator companies’ strategies of getting the patented product life extended through protecting improvement innovations and maintain market exclusivity even after the expiration of the compound patent. The battle for market and drive for higher profits between generics and innovator drug companies has extended the application of at-risk launch of the generic drugs even when compound patent is still running. Sitagliptin (Januvia) may be ranked at top of the drugs that have been fiercely litigated in the developing countries during their patent term. This article reviews the outcome of sitagliptin patent litigation and impact on the market exclusivity in some developing countries. This takes the position that the existing conflict between the innovators and generics can be resolved by diluting the misconception that patents on improvement innovations are misuse of patent system or inappropriate extension of patented product life on the part of innovator companies. Whether trivial, simplified or complex, if novel and non-obvious, further improvements in the precursor drugs are patentable within the legal framework of the patent system. The real issue is the scope of monopoly granted to the secondary or follow-on patents. Once the compound patent has expired, follow-on patents on improvements relating to the same compound should not be allowed to use as legal-barrier for the generic medicines entry to the market.
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Metz, Alexander, Jan Wollenhaupt, Steffen Glöckner, Niki Messini, Simon Huber, Tatjana Barthel, Ahmed Merabet, et al. "Frag4Lead: growing crystallographic fragment hits by catalog using fragment-guided template docking." Acta Crystallographica Section D Structural Biology 77, no. 9 (August 23, 2021): 1168–82. http://dx.doi.org/10.1107/s2059798321008196.
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In recent years, crystallographic fragment screening has matured into an almost routine experiment at several modern synchrotron sites. The hits of the screening experiment, i.e. small molecules or fragments binding to the target protein, are revealed along with their 3D structural information. Therefore, they can serve as useful starting points for further structure-based hit-to-lead development. However, the progression of fragment hits to tool compounds or even leads is often hampered by a lack of chemical feasibility. As an attractive alternative, compound analogs that embed the fragment hit structurally may be obtained from commercial catalogs. Here, a workflow is reported based on filtering and assessing such potential follow-up compounds by template docking. This means that the crystallographic binding pose was integrated into the docking calculations as a central starting parameter. Subsequently, the candidates are scored on their interactions within the binding pocket. In an initial proof-of-concept study using five starting fragments known to bind to the aspartic protease endothiapepsin, 28 follow-up compounds were selected using the designed workflow and their binding was assessed by crystallography. Ten of these compounds bound to the active site and five of them showed significantly increased affinity in isothermal titration calorimetry of up to single-digit micromolar affinity. Taken together, this strategy is capable of efficiently evolving the initial fragment hits without major synthesis efforts and with full control by X-ray crystallography.
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Rietz, Anne, Kevin J. Hodgetts, Hrvoje Lusic, Kevin M. Quist, Erkan Y. Osman, Christian L. Lorson, and Elliot J. Androphy. "Short-duration splice promoting compound enables a tunable mouse model of spinal muscular atrophy." Life Science Alliance 4, no. 1 (November 24, 2020): e202000889. http://dx.doi.org/10.26508/lsa.202000889.
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Spinal muscular atrophy (SMA) is a motor neuron disease and the leading genetic cause of infant mortality. SMA results from insufficient survival motor neuron (SMN) protein due to alternative splicing. Antisense oligonucleotides, gene therapy and splicing modifiers recently received FDA approval. Although severe SMA transgenic mouse models have been beneficial for testing therapeutic efficacy, models mimicking milder cases that manifest post-infancy have proven challenging to develop. We established a titratable model of mild and moderate SMA using the splicing compound NVS-SM2. Administration for 30 d prevented development of the SMA phenotype in severe SMA mice, which typically show rapid weakness and succumb by postnatal day 11. Furthermore, administration at day eight resulted in phenotypic recovery. Remarkably, acute dosing limited to the first 3 d of life significantly enhanced survival in two severe SMA mice models, easing the burden on neonates and demonstrating the compound as suitable for evaluation of follow-on therapies without potential drug–drug interactions. This pharmacologically tunable SMA model represents a useful tool to investigate cellular and molecular pathogenesis at different stages of disease.
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Cohen, Y. C., S. Hassin-Baer, L. Olmer, R. Barishev, Y. Goldhammer, L. Freedman, and B. Mozes. "MS-CANE: a computer-aided instrument for neurological evaluation of patients with multiple sclerosis: enhanced reliability of expanded disability status scale (EDSS) assessment." Multiple Sclerosis Journal 6, no. 5 (October 2000): 355–61. http://dx.doi.org/10.1177/135245850000600511.
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Kurtzke's EDSS remains the most widely-used measure for clinical evaluation of MS patients. However, several studies have demonstrated the limited reliability of this tool. We introduce a computerized instrument, MS-CANE (Multiple Sclerosis Computer-Aided Neurological Examination), for clinical evaluation and follow up of patients with multiple sclerosis (MS) and to compare its reliability to that of conventional Expanded Disability Status Scale (EDSS) assessment. We developed a computerized interactive instrument, based on the following principles: structured gathering of neurological findings, reduction of compound notions to their basic components, use of precise definitions, priority setting and automated calculations of EDSS and functional systems scores. An expert panel examined the consistency of MS-CANE with Kurtzke's specifications. To determine the effect of MS-CANE on the reliability of EDSS assessment, 56 MS patients underwent paired conventional EDSS and MS-CANE-based evaluations. The inter-observer agreement in both methods was determined and compared using the kappa statistic. The expert panel judged the tool to be compatible with the basic concepts of Kurtzke's EDSS. The use of MS-CANE increased the reliability of EDSS assessment: Kappa statistic was found to be 0.42 (i.e. moderate agreement) for conventional EDSS assessment versus 0.69 (i.e. substantial agreement) for MS-CANE (P=0.002). We conclude that the use of this tool may contribute towards a standardized and reliable assessment of EDSS. Within clinical trials, this could increase the power to detect effects, thus reducing trial duration and the cohort size required.
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Kashyap, Surender, and Anjali Solanki. "Challenges in Endobronchial Tuberculosis: From Diagnosis to Management." Pulmonary Medicine 2014 (2014): 1–8. http://dx.doi.org/10.1155/2014/594806.
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Despite the rapid advancement in diagnostic and therapeutic modalities, endobronchial tuberculosis (EBTB), defined as tuberculous infection of the tracheobronchial tree, continues to remain challenging for clinicians. Nonspecific respiratory symptoms along with normal chest radiograph in 10–20% of cases may be alleged for the diagnostic delay. Variable diagnostic yield with sputum microscopy might further compound the problem. In such cases, high resolution computed tomography (HRCT) works as a more sensitive tool and demonstrates involvement of tracheobronchial tree described classically as “tree-in-bud” appearance. Bronchoscopic biopsy is considered the most reliable method for confirmation of the diagnosis with 30% to 84% positivity in different series. Evolution of the disease is also unpredictable with frequent progression to bronchostenosis, therefore requiring regular follow-up and early intervention to halt the natural course. This review article elaborates various aspects of the disease with specific focus on diagnostic dilemma and recent advances in interventional bronchoscopy. In addition, this discussion evokes optimism for further research and introduction of innovative therapeutic modalities.
Dissertations / Theses on the topic "Compound follow-on tool"
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Kučera, Jiří. "Výroba krytu brzdového kotouče sdruženým nástrojem." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2015. http://www.nusl.cz/ntk/nusl-231759.
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This project is conceived within the master's degree in engineering technology and industry management (M2I-K Engineering) technology by design of the brake disc cover in compound tool, with year production 500 000 pcs. The material is deep-drawn sheet metal 11 305.21, 1 mm thickness. It is based on the literature studies about forming and calculation was suggested several variants of the present components. The proposed tool is clamped in the crank press LDC 400 firm Šmeral with a nominal force of 4000 kN. The functional parts are made from steel 19 573. The proposed technology of the deep drawing was verified by using simulation program AutoForm.
Book chapters on the topic "Compound follow-on tool"
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Martinho Simões, José A., and Manuel Minas da Piedade. "Photoacoustic Calorimetry." In Molecular Energetics. Oxford University Press, 2008. http://dx.doi.org/10.1093/oso/9780195133196.003.0017.
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“Any chemical species, which under ambient conditions (i.e., a temperature around 25°C, and a pressure close to 1 atm) will, for a combination of kinetic and thermodynamic reasons, decay on a timescale ranging from microseconds, or even nanoseconds, to a few minutes” can be classified as a short-lived compound. According to this definition, suggested by Almond, it is clear that the experimental methods described in previous chapters can only be used to study the thermochemistry of long-lived substances. The technique that we address here, known as photoacoustic calorimetry (PAC) or laser-induced optoacoustic calorimetry (LIOAC), is suitable for investigating the energetics of molecules with lifetimes smaller than about 1μs. It relies on the photoacoustic effect, which was discovered by Bell more than 100 years ago. With the assistance of Tainter, he was able to “devise a method of producing sounds by the action of an intermittent beam of light” and conclude that the method “can be adapted to solids, liquids, and gases”. Figure 13.1 shows a photophone, “an apparatus for the production of sound by light,” used by Bell to investigate the photoacoustic effect. The controversy around the origin of this phenomenon was settled by Bell himself and by Lord Rayleigh; their views were rather close to our present understanding: When a light pulse is absorbed by a substance, a given amount of heat is deposited, producing a local thermal expansion; this thermal expansion propagates through the medium, generating sound waves. The basic theory of the photoacoustic effect was described by Tam and Patel and some of its applications were presented in a review by Braslavsky and Heibel. The first use of PAC to determine enthalpies of chemical reactions was reported by the groups of Peters and Braslavsky. The same groups have also played an important role in developing the methodologies to extract those thermodynamic data from the experimentally measured quantities. In the ensuing discussion, we closely follow a publication where the use of the photoacoustic calorimety technique as a thermochemical tool was examined. Consider the elementary design of a photoacoustic calorimeter, shown in figure 13.3. The cell contains the sample, which is, for instance, a dilute solution of a photoreactive species.
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Diaz-Caceres, Nelson, and Carlos Salcedo-Perez. "Corporate Sustainability in Bogotanian Small and Medium Enterprises." In Handbook of Research on Intrapreneurship and Organizational Sustainability in SMEs, 121–39. IGI Global, 2018. http://dx.doi.org/10.4018/978-1-5225-3543-0.ch006.
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Nowadays, sustainability is a key issue for companies, governments and societies. However, for many small and medium entrepreneurs, the concept is still unknown, difficult to understand and/or considered irrelevant. Sustainability is composed by three dimensions: economic, social and environmental. This chapter will concentrate on the economic dimension, and in order to find out the real state of sustainability in Bogotanian small and medium enterprises, the authors applied the sustainability matrix, a research tool designed to determine the state of planning, implementation and impact of sustainability in enterprises. Results show small and medium Bogotanian enterprises perform fine as long as they follow their own planning, however they do not perform as well when implementing what they plan, attempting to achieve economic sustainability.
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Berg, Benjamin, and Mor Harchol-Balter. "Optimal Scheduling of Parallel Jobs With Unknown Service Requirements." In Advances in Systems Analysis, Software Engineering, and High Performance Computing, 18–40. IGI Global, 2021. http://dx.doi.org/10.4018/978-1-7998-7156-9.ch003.
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Large data centers composed of many servers provide the opportunity to improve performance by parallelizing jobs. However, effectively exploiting parallelism is non-trivial. For each arriving job, one must decide the number of servers on which the job is run. The goal is to determine the optimal allocation of servers to jobs that minimizes the mean response time across jobs – the average time from when a job arrives until it completes. Parallelizing a job across multiple servers reduces the response time of that individual job. However, jobs receive diminishing returns from being allocated additional servers, so allocating too many servers to a single job leads to low system efficiency. The authors consider the case where the remaining sizes of jobs are unknown to the system at every moment in time. They prove that, if all jobs follow the same speedup function, the optimal policy is EQUI, which divides servers equally among jobs. When jobs follow different speedup functions, EQUI is no longer optimal and they provide an alternate policy, GREEDY*, which performs within 1% of optimal in simulation.
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Sawicki, Sandro, Rafael Z. Frantz, Vitor Manuel Basto Fernandes, Fabricia Roos-Frantz, Iryna Yevseyeva, and Rafael Corchuelo. "Characterising Enterprise Application Integration Solutions as Discrete-Event Systems." In Advances in Systems Analysis, Software Engineering, and High Performance Computing, 261–88. IGI Global, 2016. http://dx.doi.org/10.4018/978-1-4666-8823-0.ch009.
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It is not difficult to find an enterprise which has a software ecosystem composed of applications that were built using different technologies, data models, operating systems, and most often were not designed to exchange data and share functionalities. Enterprise Application Integration provides methodologies and tools to design and implement integration solutions. The state-of-the-art integration technologies provide a domain-specific language that enables the design of conceptual models for integration solutions. The analysis of integration solutions to predict their behaviour and find possible performance bottlenecks is an important activity that contributes to increase the quality of the delivered solutions, however, software engineers follow a costly, risky, and time-consuming approach. Integration solutions shall be understood as a discrete-event system. This chapter introduces a new approach based on simulation to take advantage of well-established techniques and tools for discrete-event simulation, cutting down cost, risk, and time to deliver better integration solutions.
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Breuer, Edward. "Naphtali Herz Wessely and the Cultural Dislocations of an Eighteenth-Century Maskil." In New Perspectives on the Haskalah, 27–47. Liverpool University Press, 2001. http://dx.doi.org/10.3828/liverpool/9781874774617.003.0003.
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This chapter focuses on Naphtali Herz Wessely, who was best known for his book Divrei shalom ve'emet (Words of Peace and Truth). Regarded as the formative text of the Haskalah, this book was a passionate response to Joseph II's Edict of Tolerance; in it, Wessely urged the Jews of the Habsburg Empire to enrol their children in state schools where they would follow a balanced curriculum, studying Jewish religious subjects as well as languages, science, and the humanities in an orderly fashion. The chapter then departs from the usual portrayal of Wessely and depicts him as alienated from both traditional and modernist Jews, as well as from the other maskilim, at least during the later years of his life. It describes Wessely's indecision and frustration, in particular his sense that no one properly understood his vision of cultural renewal, and it shows how Wessely's alienation was compounded by his anxiety about the growing dimensions of religious heresy and by his disaffection from traditional circles. The chapter also analyses Wessely's early writings, revealing that his major interests were twofold: the revival of biblical Hebrew as an essential tool for a more precise understanding of rabbinic literature, and an affirmation of the credibility of the Oral Torah that was being criticized by European scholars.
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Hammerson, Geoffrey A., and Larry E. Morse. "State of the States: Geographic Patterns of Diversity, Rarity, and Endemism." In Precious Heritage. Oxford University Press, 2000. http://dx.doi.org/10.1093/oso/9780195125191.003.0011.
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The natural geography of the 50 states varies tremendously, supporting an equally varied suite of wild species—from flocks of tropical birds in southern Florida to caribou migrations across the Alaskan tundra. The geography of risk, too, varies across the nation, reflecting the interaction between natural and human history. Similarly, present-day land and water uses will largely determine the future diversity and condition of the flora and fauna. We can learn much, though, from looking at the current condition of a state’s biota, since this both reflects the past and helps illuminate the future. A state’s ecological complexion and the evolutionary history of its biota are the primary determinants of its biological diversity. These environmental factors have encouraged spectacular diversification in many regions: for instance, the freshwater fish fauna in the Southeast, the magnificent conifers along the Pacific cordillera, and the small mammal assemblages of the arid Southwest. Conversely, geological events such as the expansion and contraction of the ice sheets have left other areas of the country with a more modest array of species. States, however, are artificial constructs laid out on the landscape’s natural ecological patterns. While some state lines follow natural boundaries, such as shorelines or major rivers, most cut across the land with no sensitivity to natural features or topography. Nonetheless, urban and rural dwellers alike identify with the major ecological regions within which they live, and this is often the source of considerable pride. Montana is “big sky country,” referring to the vast open plains that sweep up against the eastern phalanx of the Rocky Mountains. California’s moniker “the golden state” now refers more to its tawny hills of summer—unfortunately at present composed mostly of alien species—than to the nuggets first found at Sutter’s Creek. Maryland, home of the Chesapeake Bay, offers the tasty blue crab (Callinectes sapidus) as its unofficial invertebrate mascot. The list could go on, evidenced by the growing number of states that offer vanity license plates celebrating their natural environment. Natural features have always played a dominant role in determining patterns of settlement and land use.
Conference papers on the topic "Compound follow-on tool"
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Ghezzi, Diego, Andrea Menegon, Alessandra Pedrocchi, Sara Mantero, Flavia Valtorta, and Giancarlo Ferrigno. "PhotoMEA: A New Step Towards Total Optical Analysis of In Vitro Neuronal Networks." In ASME 8th Biennial Conference on Engineering Systems Design and Analysis. ASMEDC, 2006. http://dx.doi.org/10.1115/esda2006-95218.
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Light stimulation of neurons is a promising approach for investigating the molecular mechanisms at the basis of neuronal physiology and plasticity. In particular, flash photolysis of caged compounds offers the unique advantage of allowing to quickly change the concentration of either intracellular or extracellular bioactive molecules, such as neurotransmitters or second messengers, for the stimulation or modulation of neuronal activity. In this field of research, we describe a simple laser-based set-up for the local activation of caged compounds. The coupling of a UV laser diode to a small-core optical fibre allows to reduce the uncaging area and to quickly change the stimulation point. The actual localisation of the light stimulation is determined using a caged fluorescent compound (dextran, DMNB-caged fluorescein). The efficiency of our set up for neuronal stimulation is tested with a caged neurotransmitter (MNI-caged-L-glutamate). Activation of caged glutamate evokes neuronal responses that are recorded using a MicroElectrode Array system and/or following the variations in the concentrations of the Cai2+. This work shows that our laser-based set-up is a powerful tool for local activation of caged compound allowing a unique opportunity to follow the effects of local neuronal pathways on neuronal network activity, for instance during pharmacological and toxicological treatments.
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Diaz-Mendez, Sosimo E., Abel Hernandez-Guerrero, Jose M. Rodriguez-Lelis, and Cuauhte´moc Rubio-Arana. "Environmental Impact Index Using Exergy Destruction Within an Ecosystem: Methodology." In ASME 2009 International Mechanical Engineering Congress and Exposition. ASMEDC, 2009. http://dx.doi.org/10.1115/imece2009-12016.
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Theoretical bases of the use of the irreversibilities concept in an ecosystem as an environment impact index are presented in this paper. Because an ecosystem is composed by different biotics and abiotics parts, each part has a specific function in the processes to transport energy inside the ecosystem, all these processes having a large dependence between them. When anthropogenic emissions is produced part of the useful energy of the process are used to assimilate or to absorb those emissions, and irreversibilities are produced in the processes of the ecosystem when emissions are made by the human beings. Thus, the work that an ecosystem can carry out varies as a function of the irreversibilities produced by anthropogenic sources; the permanency or loss of the ecosystem depends on how many irreversibilities it can support. The second law of thermodynamics through a systematic use of the exergy concept o lost work concept are the basis of this methodology. The ecosystem can be divided in subsystems, each subsystem interrelated with the other ones, and then an ideal work variation can be obtained from each variation in the ecosystem (being the subsystems the water, the soil, the atmosphere, the organisms and the society). Thus, a global index could be determined by adding the partial irreversibility of each subsystem, and could be used to determine the trend that an ecosystem will follow due to alterations of its pristine, original or environmental line base state. Applying the methodology presented here an index of environmental impact could be developed, not in a subjective or ambiguous way, but based on energy calculations. An index of environmental impact and its methodology, based on quantitative terms that enable to evaluate in a very clear way the harmful effects of industrial operations, such as the phenomenon of contamination of the environment, could be used as a tool in the analysis of sustainability, resource depletion or health effects.