Adrenal imaging agents

International Nuclear Information System (INIS)

Davis, M.A.; Hanson, R.N.; Holman, B.L.

1980-01-01

The goals of this proposal are the development of selenium-containing analogs of the aromatic amino acids as imaging agents for the pancreas and of the adrenal cortex enzyme inhibitors as imaging agents for adrenal pathology. The objects for this year include (a) the synthesis of methylseleno derivatives of phenylalanine and tryptophan, and (b) the preparation and evaluation of radiolabeled iodobenzoyl derivatives of the selenazole and thiazole analogs of metyrapone and SU-9055

Synthetic Curcumin Analogs as Inhibitors of β -Amyloid Peptide Aggregation: Potential Therapeutic and Diagnostic Agents for Alzheimer's Disease.

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Bukhari, Syed Nasir Abbas; Jantan, Ibrahim

2015-01-01

There is a crucial need to develop new effective drugs for Alzheimer's disease (AD) as the currently available AD treatments provide only momentary and incomplete symptomatic relief. Amongst natural products, curcumin, a major constituent of turmeric, has been intensively investigated for its neuroprotective effect against β-amyloid (Aβ)-induced toxicity in cultured neuronal cells. The ability of curcumin to attach to Aβ peptide and prevent its accumulation is attributed to its three structural characteristics such as the presence of two aromatic end groups and their co-planarity, the length and rigidity of the linker region and the substitution conformation of these aromatics. However, curcumin failed to reach adequate brain levels after oral absorption in AD clinical trials due to its low water solubility and poor oral bioavailability. A number of new curcumin analogs that mimic the active site of the compound along with analogs that mimic the curcumin anti-amyloid effect combined with anticholinesterase effect have been developed to enhance the bioavailability, pharmacokinetics, water solubility, stability at physiological conditions and delivery of curcumin. In this article, we have summarized all reported synthetic analogs of curcumin showing effects on β-amyloid and discussed their potential as therapeutic and diagnostic agents for AD.

Are gadolinium contrast agents suitable for gadolinium neutron capture therapy?

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De Stasio, Gelsomina; Rajesh, Deepika; Casalbore, Patrizia; Daniels, Matthew J; Erhardt, Robert J; Frazer, Bradley H; Wiese, Lisa M; Richter, Katherine L; Sonderegger, Brandon R; Gilbert, Benjamin; Schaub, Sebastien; Cannara, Rachel J; Crawford, John F; Gilles, Mary K; Tyliszczak, Tolek; Fowler, John F; Larocca, Luigi M; Howard, Steven P; Mercanti, Delio; Mehta, Minesh P; Pallini, Roberto

2005-06-01

Gadolinium neutron capture therapy (GdNCT) is a potential treatment for malignant tumors based on two steps: (1) injection of a tumor-specific (157)Gd compound; (2) tumor irradiation with thermal neutrons. The GdNC reaction can induce cell death provided that Gd is proximate to DNA. Here, we studied the nuclear uptake of Gd by glioblastoma (GBM) tumor cells after treatment with two Gd compounds commonly used for magnetic resonance imaging, to evaluate their potential as GdNCT agents. Using synchrotron X-ray spectromicroscopy, we analyzed the Gd distribution at the subcellular level in: (1) human cultured GBM cells exposed to Gd-DTPA or Gd-DOTA for 0-72 hours; (2) intracerebrally implanted C6 glioma tumors in rats injected with one or two doses of Gd-DOTA, and (3) tumor samples from GBM patients injected with Gd-DTPA. In cell cultures, Gd-DTPA and Gd-DOTA were found in 84% and 56% of the cell nuclei, respectively. In rat tumors, Gd penetrated the nuclei of 47% and 85% of the tumor cells, after single and double injection of Gd-DOTA, respectively. In contrast, in human GBM tumors 6.1% of the cell nuclei contained Gd-DTPA. Efficacy of Gd-DTPA and Gd-DOTA as GdNCT agents is predicted to be low, due to the insufficient number of tumor cell nuclei incorporating Gd. Although multiple administration schedules in vivo might induce Gd penetration into more tumor cell nuclei, a search for new Gd compounds with higher nuclear affinity is warranted before planning GdNCT in animal models or clinical trials.

Molecular Medicine: Synthesis and In Vivo Detection of Agents for use in Boron Neutron Capture Therapy. Final Report

International Nuclear Information System (INIS)

Kabalka, G. W.

2005-01-01

The primary objective of the project was the development of in vivo methods for the detection and evaluation of tumors in humans. The project was focused on utilizing positron emission tomography (PET) to monitor the distribution and pharmacokinetics of a current boron neutron capture therapy (BNCT) agent, p-boronophenylalanine (BPA) by labeling it with a fluorine-18, a positron emitting isotope. The PET data was then used to develop enhanced treatment planning protocols. The study also involved the synthesis of new tumor selective BNCT agents that could be labeled with radioactive nuclides for the in vivo detection of boron

Capturing multi-stage fuzzy uncertainties in hybrid system dynamics and agent-based models for enhancing policy implementation in health systems research.

Science.gov (United States)

Liu, Shiyong; Triantis, Konstantinos P; Zhao, Li; Wang, Youfa

2018-01-01

In practical research, it was found that most people made health-related decisions not based on numerical data but on perceptions. Examples include the perceptions and their corresponding linguistic values of health risks such as, smoking, syringe sharing, eating energy-dense food, drinking sugar-sweetened beverages etc. For the sake of understanding the mechanisms that affect the implementations of health-related interventions, we employ fuzzy variables to quantify linguistic variable in healthcare modeling where we employ an integrated system dynamics and agent-based model. In a nonlinear causal-driven simulation environment driven by feedback loops, we mathematically demonstrate how interventions at an aggregate level affect the dynamics of linguistic variables that are captured by fuzzy agents and how interactions among fuzzy agents, at the same time, affect the formation of different clusters(groups) that are targeted by specific interventions. In this paper, we provide an innovative framework to capture multi-stage fuzzy uncertainties manifested among interacting heterogeneous agents (individuals) and intervention decisions that affect homogeneous agents (groups of individuals) in a hybrid model that combines an agent-based simulation model (ABM) and a system dynamics models (SDM). Having built the platform to incorporate high-dimension data in a hybrid ABM/SDM model, this paper demonstrates how one can obtain the state variable behaviors in the SDM and the corresponding values of linguistic variables in the ABM. This research provides a way to incorporate high-dimension data in a hybrid ABM/SDM model. This research not only enriches the application of fuzzy set theory by capturing the dynamics of variables associated with interacting fuzzy agents that lead to aggregate behaviors but also informs implementation research by enabling the incorporation of linguistic variables at both individual and institutional levels, which makes unstructured linguistic data

Development and evaluation of a novel radioiodinated vesamicol analog as a sigma receptor imaging agent.

Science.gov (United States)

Ogawa, Kazuma; Kanbara, Hiroya; Shiba, Kazuhiro; Kitamura, Yoji; Kozaka, Takashi; Kiwada, Tatsuto; Odani, Akira

2012-09-28

Sigma receptors are highly expressed in human tumors and should be appropriate targets for developing tumor imaging agents. Previously, we synthesized a vesamicol analog, (+)-2-[4-(4-iodophenyl)piperidino]cyclohexanol ((+)-pIV), with a high affinity for sigma receptors and prepared radioiodinated (+)-pIV. As a result, (+)-[125I]pIV showed high tumor uptake in biodistribution experiments. However, the accumulation of radioactivity in normal tissues, such as the liver, was high. We supposed that some parts of the accumulation of (+)-pIV in the liver should be because of its high lipophilicity, and prepared and evaluated a more hydrophilic radiolabeled vesamicol analog, (+)-4-[1-(2-hydroxycyclohexyl)piperidine-4-yl]-2-iodophenol ((+)-IV-OH). (+)-[125I]IV-OH was prepared by the chloramine T method from the precursor. The partition coefficient of (+)-[125I]IV-OH was measured. Biodistribution experiments were performed by intravenous administration of a mixed solution of (+)-[125I]IV-OH and (+)-[131I]pIV into DU-145 tumor-bearing mice. Blocking studies were performed by intravenous injection of (+)-[125I]IV-OH mixed with an excess amount of ligand into DU-145 tumor-bearing mice. The hydrophilicity of (+)-[125I]IV-OH was much higher than that of (+)-[125I]pIV. In biodistribution experiments, (+)-[125I]IV-OH and (+)-[131I]pIV showed high uptake in tumor tissues at 10-min post-injection. Although (+)-[131I]pIV tended to be retained in most tissues, (+)-[125I]IV-OH was cleared from most tissues. In the liver, the radioactivity level of (+)-[125I]IV-OH was significantly lower at all time points compared to those of (+)-[131I]pIV. In the blocking studies, co-injection of an excess amount of sigma ligands resulted in significant decreases of tumor/blood uptake ratios after injection of (+)-[125I]IV-OH. The results indicate that radioiodinated (+)-IV-OH holds a potential as a sigma receptor imaging agent.

Synthesis and structure-distribution study of radioiodinated norepinephrine storage analogs

Energy Technology Data Exchange (ETDEWEB)

Wieland, D.M.; Inbasekaran, M.; Brown, L.E.; Marsh, D.D.; Beierwaltes, W.H. (Michigan Univ., Ann Arbor (USA). Medical Center)

Unlabelled analogs of norepinephrine have been synthesised and then labelled with /sup 125/I in an attempt to find an agent with heart uptake and neuronal specificity greater than metaiodobenzylguanidine (MIBG). The analogs of norepinephrine were injected intravenously into dogs and showed a heart concentration similar to MIBG. Neuronal specificity of some analogs is being evaluated in rat heart.

Synthesis and structure-distribution study of radioiodinated norepinephrine storage analogs

International Nuclear Information System (INIS)

Wieland, D.M.; Inbasekaran, M.; Brown, L.E.; Marsh, D.D.; Beierwaltes, W.H.

1982-01-01

Unlabelled analogs of norepinephrine have been synthesised and then labelled with 125 I in an attempt to find an agent with heart uptake and neuronal specificity greater than metaiodobenzylguanidine (MIBG). The analogs of norepinephrine were injected intravenously into dogs and showed a heart concentration similar to MIBG. Neuronal specificity of some analogs is being evaluated in rat heart. (U.K.)

Context, cortex, and associations: a connectionist developmental approach to verbal analogies

Science.gov (United States)

Kollias, Pavlos; McClelland, James L.

2013-01-01

We present a PDP model of binary choice verbal analogy problems (A:B as C:[D1|D2], where D1 and D2 represent choice alternatives). We train a recurrent neural network in item-relation-item triples and use this network to test performance on analogy questions. Without training on analogy problems per se, the model explains the developmental shift from associative to relational responding as an emergent consequence of learning upon the environment's statistics. Such learning allows gradual, item-specific acquisition of relational knowledge to overcome the influence of unbalanced association frequency, accounting for association effects of analogical reasoning seen in cognitive development. The network also captures the overall degradation in performance after anterior temporal damage by deleting a fraction of learned connections, while capturing the return of associative dominance after frontal damage by treating frontal structures as necessary for maintaining activation of A and B while seeking a relation between C and D. While our theory is still far from being complete it provides a unified explanation of findings that need to be considered together in any integrated account of analogical reasoning. PMID:24312068

Context, cortex, and associations: a connectionist developmental approach to verbal analogies

Directory of Open Access Journals (Sweden)

Pavlos eKollias

2013-11-01

Full Text Available We present a PDP model of binary choice verbal analogy problems (A:B as C:[D1|D2], where D1 and D2 represent choice alternatives. We train a recurrent neural network in item-relation- item triples and use this network to test performance on analogy questions. Without training on analogy problems per se, the model explains the developmental shift from associative to relational responding as an emergent consequence of learning upon the environment’s statistics. Such learning allows gradual, item-specific acquisition of relational knowledge to overcome the influence of unbalanced association frequency, accounting for association effects of analogical reasoning seen in cognitive development. The network also captures the overall degradation in performance after anterior temporal damage by deleting a fraction of learned connections, while capturing the return of associative dominance after frontal damage by treating frontal structures as necessary for maintaining activation of A and B while seeking a relation between C and D. While our theory is still far from being complete it provides a unified explanation of findings that need to be considered together in any integrated account of analogical reasoning.

Context, cortex, and associations: a connectionist developmental approach to verbal analogies.

Science.gov (United States)

Kollias, Pavlos; McClelland, James L

2013-01-01

We present a PDP model of binary choice verbal analogy problems (A:B as C:[D1|D2], where D1 and D2 represent choice alternatives). We train a recurrent neural network in item-relation-item triples and use this network to test performance on analogy questions. Without training on analogy problems per se, the model explains the developmental shift from associative to relational responding as an emergent consequence of learning upon the environment's statistics. Such learning allows gradual, item-specific acquisition of relational knowledge to overcome the influence of unbalanced association frequency, accounting for association effects of analogical reasoning seen in cognitive development. The network also captures the overall degradation in performance after anterior temporal damage by deleting a fraction of learned connections, while capturing the return of associative dominance after frontal damage by treating frontal structures as necessary for maintaining activation of A and B while seeking a relation between C and D. While our theory is still far from being complete it provides a unified explanation of findings that need to be considered together in any integrated account of analogical reasoning.

Multi-targeting Andrographolide and its Natural Analogs as Potential Therapeutic Agents.

Science.gov (United States)

Kishore, V; Yarla, Nagendra Sastry; Bishayee, Anupam; Putta, Swathi; Malla, Ramarao; Neelapu, Nageswara Rao Reddy; Challa, Surekha; Das, Subhasish; Shiralgi, Yallappa; Hegde, Gurumurthy; Dhananjaya, Bhadrapura Lakkappa

2017-01-01

Andrographis paniculata (A. paniculata) is a medicinal plant used in the Indian and Chinese traditional medicinal systems for its various beneficial properties of therapeutics. This is due to the presence of a diterpene lactone called 'andrographolide'. Several biological activities like antiinflammatory, antitumour, anti-hyperglycaemic, anti-fertility, antiviral, cardio protective and hepatoprotective properties are attributed to andrographolide and its natural analogs. The studies have shown that not only this diterpene lactone (andrographolide), but also other related terpenoid analogs from A. paniculata could be exploited for disease prevention due to their structural similarity with diverse pharmacological activities. Several scientific groups are trying to unveil the underlying mechanisms involved in these biological actions brough aout by andrographolide and its analogs. This review aims at giving an overview on the therapeutical and/or pharmacological activities of andrographolide and its derivatives and also exemplify the underlying mechanisms involved. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Constant-parameter capture-recapture models

Science.gov (United States)

Brownie, C.; Hines, J.E.; Nichols, J.D.

1986-01-01

Jolly (1982, Biometrics 38, 301-321) presented modifications of the Jolly-Seber model for capture-recapture data, which assume constant survival and/or capture rates. Where appropriate, because of the reduced number of parameters, these models lead to more efficient estimators than the Jolly-Seber model. The tests to compare models given by Jolly do not make complete use of the data, and we present here the appropriate modifications, and also indicate how to carry out goodness-of-fit tests which utilize individual capture history information. We also describe analogous models for the case where young and adult animals are tagged. The availability of computer programs to perform the analysis is noted, and examples are given using output from these programs.

Fast event recorder utilizing a CCD analog shift register

International Nuclear Information System (INIS)

Ducar, R.J.; McIntyre, P.M.

1978-01-01

A system of electronics has been developed to allow the capture and recording of relatively fast, low-amplitude analog events. The heart of the system is a dual 455-cell analog shift register charge-coupled device, Fairchild CCD321ADC-3. The CCD is operated in a dual clock mode. The input is sampled at a selectable clock rate of .25-20 MHz. The stored analog data is then clocked out at a slower rate, typically about .25 MHz. The time base expansion of the analog data allows for analog-to-digital conversion and memory storage using conventional medium-speed devices. The digital data is sequentially loaded into a static RAM and may then be block transferred to a computer. The analog electronics are housed in a single-width NIM module, and the RAM memory in a single-width CAMAC module. Each pair of modules provides six parallel channels. Cost is about $200.00 per channel. Applications are described for ionization imaging (TPC, IRC) and long-drift calorimetry in liquid argon

Synthesis of 4-thiazolidinone analogs as potent in vitro anti-urease agents.

Science.gov (United States)

Rahim, Fazal; Zaman, Khalid; Ullah, Hayat; Taha, Muhammad; Wadood, Abdul; Javed, Muhammad Tariq; Rehman, Wajid; Ashraf, Muhammad; Uddin, Reaz; Uddin, Imad; Asghar, Humna; Khan, Aftab Ahmad; Khan, Khalid M

2015-12-01

4-Thiazolidinone analogs 1-20 were synthesized, characterized by (1)H NMR and EI-MS and investigated for urease inhibitory activity. All twenty (20) analogs exhibited varied degree of urease inhibitory potential with IC50 values 1.73-69.65μM, if compared with standard thiourea having IC50 value of 21.25±0.15μM. Among the series, eight derivatives 3, 6, 8, 10, 15, 17, 19, and 20 showed outstanding urease inhibitory potential with IC50 values of 9.34±0.02, 14.62±0.03, 8.43±0.01, 7.3±0.04, 2.31±0.002, 5.75±0.003, 8.81±0.005, and 1.73±0.001μM, respectively, which is better than the standard thiourea. The remaining analogs showed good to excellent urease inhibition. The binding interactions of these compounds were confirmed through molecular docking studies. Copyright © 2015 Elsevier Inc. All rights reserved.

Event-Based Computation of Motion Flow on a Neuromorphic Analog Neural Platform.

Science.gov (United States)

Giulioni, Massimiliano; Lagorce, Xavier; Galluppi, Francesco; Benosman, Ryad B

2016-01-01

Estimating the speed and direction of moving objects is a crucial component of agents behaving in a dynamic world. Biological organisms perform this task by means of the neural connections originating from their retinal ganglion cells. In artificial systems the optic flow is usually extracted by comparing activity of two or more frames captured with a vision sensor. Designing artificial motion flow detectors which are as fast, robust, and efficient as the ones found in biological systems is however a challenging task. Inspired by the architecture proposed by Barlow and Levick in 1965 to explain the spiking activity of the direction-selective ganglion cells in the rabbit's retina, we introduce an architecture for robust optical flow extraction with an analog neuromorphic multi-chip system. The task is performed by a feed-forward network of analog integrate-and-fire neurons whose inputs are provided by contrast-sensitive photoreceptors. Computation is supported by the precise time of spike emission, and the extraction of the optical flow is based on time lag in the activation of nearby retinal neurons. Mimicking ganglion cells our neuromorphic detectors encode the amplitude and the direction of the apparent visual motion in their output spiking pattern. Hereby we describe the architectural aspects, discuss its latency, scalability, and robustness properties and demonstrate that a network of mismatched delicate analog elements can reliably extract the optical flow from a simple visual scene. This work shows how precise time of spike emission used as a computational basis, biological inspiration, and neuromorphic systems can be used together for solving specific tasks.

Crows spontaneously exhibit analogical reasoning.

Science.gov (United States)

Smirnova, Anna; Zorina, Zoya; Obozova, Tanya; Wasserman, Edward

2015-01-19

Analogical reasoning is vital to advanced cognition and behavioral adaptation. Many theorists deem analogical thinking to be uniquely human and to be foundational to categorization, creative problem solving, and scientific discovery. Comparative psychologists have long been interested in the species generality of analogical reasoning, but they initially found it difficult to obtain empirical support for such thinking in nonhuman animals (for pioneering efforts, see [2, 3]). Researchers have since mustered considerable evidence and argument that relational matching-to-sample (RMTS) effectively captures the essence of analogy, in which the relevant logical arguments are presented visually. In RMTS, choice of test pair BB would be correct if the sample pair were AA, whereas choice of test pair EF would be correct if the sample pair were CD. Critically, no items in the correct test pair physically match items in the sample pair, thus demanding that only relational sameness or differentness is available to support accurate choice responding. Initial evidence suggested that only humans and apes can successfully learn RMTS with pairs of sample and test items; however, monkeys have subsequently done so. Here, we report that crows too exhibit relational matching behavior. Even more importantly, crows spontaneously display relational responding without ever having been trained on RMTS; they had only been trained on identity matching-to-sample (IMTS). Such robust and uninstructed relational matching behavior represents the most convincing evidence yet of analogical reasoning in a nonprimate species, as apes alone have spontaneously exhibited RMTS behavior after only IMTS training. Copyright © 2015 Elsevier Ltd. All rights reserved.

Eye Movements Reveal Optimal Strategies for Analogical Reasoning.

Science.gov (United States)

Vendetti, Michael S; Starr, Ariel; Johnson, Elizabeth L; Modavi, Kiana; Bunge, Silvia A

2017-01-01

Analogical reasoning refers to the process of drawing inferences on the basis of the relational similarity between two domains. Although this complex cognitive ability has been the focus of inquiry for many years, most models rely on measures that cannot capture individuals' thought processes moment by moment. In the present study, we used participants' eye movements to investigate reasoning strategies in real time while solving visual propositional analogy problems (A:B::C:D). We included both a semantic and a perceptual lure on every trial to determine how these types of distracting information influence reasoning strategies. Participants spent more time fixating the analogy terms and the target relative to the other response choices, and made more saccades between the A and B items than between any other items. Participants' eyes were initially drawn to perceptual lures when looking at response choices, but they nonetheless performed the task accurately. We used participants' gaze sequences to classify each trial as representing one of three classic analogy problem solving strategies and related strategy usage to analogical reasoning performance. A project-first strategy, in which participants first extrapolate the relation between the AB pair and then generalize that relation for the C item, was both the most commonly used strategy as well as the optimal strategy for solving visual analogy problems. These findings provide new insight into the role of strategic processing in analogical problem solving.

Eye Movements Reveal Optimal Strategies for Analogical Reasoning

Directory of Open Access Journals (Sweden)

Michael S. Vendetti

2017-06-01

Full Text Available Analogical reasoning refers to the process of drawing inferences on the basis of the relational similarity between two domains. Although this complex cognitive ability has been the focus of inquiry for many years, most models rely on measures that cannot capture individuals' thought processes moment by moment. In the present study, we used participants' eye movements to investigate reasoning strategies in real time while solving visual propositional analogy problems (A:B::C:D. We included both a semantic and a perceptual lure on every trial to determine how these types of distracting information influence reasoning strategies. Participants spent more time fixating the analogy terms and the target relative to the other response choices, and made more saccades between the A and B items than between any other items. Participants' eyes were initially drawn to perceptual lures when looking at response choices, but they nonetheless performed the task accurately. We used participants' gaze sequences to classify each trial as representing one of three classic analogy problem solving strategies and related strategy usage to analogical reasoning performance. A project-first strategy, in which participants first extrapolate the relation between the AB pair and then generalize that relation for the C item, was both the most commonly used strategy as well as the optimal strategy for solving visual analogy problems. These findings provide new insight into the role of strategic processing in analogical problem solving.

Neurotoxic Alkaloids: Saxitoxin and Its Analogs

Directory of Open Access Journals (Sweden)

Troco K. Mihali

2010-07-01

Full Text Available Saxitoxin (STX and its 57 analogs are a broad group of natural neurotoxic alkaloids, commonly known as the paralytic shellfish toxins (PSTs. PSTs are the causative agents of paralytic shellfish poisoning (PSP and are mostly associated with marine dinoflagellates (eukaryotes and freshwater cyanobacteria (prokaryotes, which form extensive blooms around the world. PST producing dinoflagellates belong to the genera Alexandrium, Gymnodinium and Pyrodinium whilst production has been identified in several cyanobacterial genera including Anabaena, Cylindrospermopsis, Aphanizomenon Planktothrix and Lyngbya. STX and its analogs can be structurally classified into several classes such as non-sulfated, mono-sulfated, di-sulfated, decarbamoylated and the recently discovered hydrophobic analogs—each with varying levels of toxicity. Biotransformation of the PSTs into other PST analogs has been identified within marine invertebrates, humans and bacteria. An improved understanding of PST transformation into less toxic analogs and degradation, both chemically or enzymatically, will be important for the development of methods for the detoxification of contaminated water supplies and of shellfish destined for consumption. Some PSTs also have demonstrated pharmaceutical potential as a long-term anesthetic in the treatment of anal fissures and for chronic tension-type headache. The recent elucidation of the saxitoxin biosynthetic gene cluster in cyanobacteria and the identification of new PST analogs will present opportunities to further explore the pharmaceutical potential of these intriguing alkaloids.

The human story of Crew 173- capturing a Mars analog mission

Science.gov (United States)

Shaw, Niamh; Musilova, Michaela; Pons Lorente, Arnau; Sisaid, Idriss; Naor, Roy; Blake, Richard

2017-04-01

An international crew of six scientists, engineers, artists and entrepreneurs with different space specialisations were selected by the Mars Society to take part in a Martian simulation in January 2017. An ambitious outreach and media strategy was developed, aimed at communicating the benefits of missions to Mars to the public and to capture the public's interest by telling the human story of the crew's mission. Entitled Crew 173 Team PRIMA, they entered the Mars Desert Research Station in the Utah Desert and conducted research in 3D printing, hydroponics, geology and astronomy. Both the scientific and community experience of this mission was documented through still image, video, audio, diary and daily journalling by the resident artist of the mission, Niamh Shaw. The full experience of the crew was documented (before, during and after the expedition), to capture each individual experience of the crew and the human experience of isolation of future human space missions.

Molecular Medicine: Synthesis and In Vivo Detection of Agents for use in Boron Neutron Capture Therapy. Final Report

Energy Technology Data Exchange (ETDEWEB)

Kabalka, G. W.

2005-06-28

The primary objective of the project was the development of in vivo methods for the detection and evaluation of tumors in humans. The project was focused on utilizing positron emission tomography (PET) to monitor the distribution and pharamacokinetics of a current boron neutron capture therapy (BNCT) agent, p-boronophenylalanine (BPA) by labeling it with a fluorine-18, a positron emitting isotope. The PET data was then used to develop enhanced treatment planning protocols. The study also involved the synthesis of new tumor selective BNCTagents that could be labeled with radioactive nuclides for the in vivo detection of boron.

Beware of being captured by an analogy: dreams are like many things.

Science.gov (United States)

Erdelyi, Matthew Hugh

2013-12-01

Classic traditions have linked dreams to memory (e.g., "dreaming is another kind of remembering" [Freud 1918/1955]) and modern notions like implicit memory subsume dreaming by definition. Llewellyn develops the more specific thesis that rapid eye movement (REM) dreams, because of their similarities to mnemonic techniques, have the function of elaboratively encoding episodic memories. This proposal is premature, requiring exigent testing. Other analogs of dreams, for example, jokes, do not invoke function but do contribute to dream science.

System and process for capture of H.sub.2S from gaseous process streams and process for regeneration of the capture agent

Science.gov (United States)

Heldenbrant, David J; Koech, Phillip K; Rainbolt, James E; Bearden, Mark D; Zheng, Feng

2014-02-18

A system and process are disclosed for selective removal and recovery of H.sub.2S from a gaseous volume, e.g., from natural gas. Anhydrous organic, sorbents chemically capture H.sub.2S gas to form hydrosulfide salts. Regeneration of the capture solvent involves addition of an anti-solvent that releases the captured H.sub.2S gas from the capture sorbent. The capture sorbent and anti-solvent are reactivated for reuse, e.g., by simple distillation.

D-piece modifications of the hemiasterlin analog HTI-286 produce potent tubulin inhibitors.

Science.gov (United States)

Zask, Arie; Birnberg, Gary; Cheung, Katherine; Kaplan, Joshua; Niu, Chuan; Norton, Emily; Yamashita, Ayako; Beyer, Carl; Krishnamurthy, Girija; Greenberger, Lee M; Loganzo, Frank; Ayral-Kaloustian, Semiramis

2004-08-16

Modifications of the D-piece carboxylic acid group of the hemiasterlin analog HTI-286 gave tubulin inhibitors which were potent cytotoxic agents in taxol resistant cell lines expressing P-glycoprotein. Amides derived from proline had potency comparable to HTI-286. Reduction of the carboxylic acid to ketones and alcohols or its conversion to acidic heterocycles also gave potent analogs. Synthetic modifications of the carboxylic acid could be carried out selectively using a wide range of synthetic reagents. Proline analog 3 was found to be effective in a human xenograft model in athymic mice.

Simultaneous electron capture and excitation in ion-atom collisions

International Nuclear Information System (INIS)

Tanis, J.A.; Bernstein, E.M.; Graham, W.G.; Clark, M.; Shafroth, S.M.; Johnson, B.M.; Jones, K.; Meron, M.

1982-01-01

A review of recent efforts to observe simultaneous electron capture-and-K-shell excitation in ion-atom collisions is presented. This process which has been referred to as resonant-transfer-and-excitation (RTE), is qualitatively analogous to dielectronic recombination (inverse Auger transition) in free-electron-ion collisions, and, hence, is expected to be resonant. Experimentally, events having the correct signature for simultaneous capture-and-excitation are isolated by detecting projectile K x rays in coincidence with ions which capture a single electron. In a recent experiment involving 70-160 MeV S 13+ ions incident on Ar, a maximum was observed in the yield of projectile K x rays associated with electron capture. This maximum is attributed to simultaneous capture - and excitation. The position (120 MeV) and width (60 MeV) of the observed maximum are in good agreement with theoretical calculations. The data indicate that RTE is an important mechanism for inner-shell vacancy production in the energy range studied

Effect of curcumin analogs onα-synuclein aggregation and cytotoxicity

Science.gov (United States)

Jha, Narendra Nath; Ghosh, Dhiman; Das, Subhadeep; Anoop, Arunagiri; Jacob, Reeba S.; Singh, Pradeep K.; Ayyagari, Narasimham; Namboothiri, Irishi N. N.; Maji, Samir K.

2016-01-01

Alpha-synuclein (α-Syn) aggregation into oligomers and fibrils is associated with dopaminergic neuron loss occurring in Parkinson’s disease (PD) pathogenesis. Compounds that modulate α-Syn aggregation and interact with preformed fibrils/oligomers and convert them to less toxic species could have promising applications in the drug development efforts against PD. Curcumin is one of the Asian food ingredient which showed promising role as therapeutic agent against many neurological disorders including PD. However, the instability and low solubility makes it less attractive for the drug development. In this work, we selected various curcumin analogs and studied their toxicity, stability and efficacy to interact with different α-Syn species and modulation of their toxicity. We found a subset of curcumin analogs with higher stability and showed that curcumin and its various analogs interact with preformed fibrils and oligomers and accelerate α-Syn aggregation to produce morphologically different amyloid fibrils in vitro. Furthermore, these curcumin analogs showed differential binding with the preformed α-Syn aggregates. The present data suggest the potential role of curcumin analogs in modulating α-Syn aggregation. PMID:27338805

Update on taxane development: new analogs and new formulations

Directory of Open Access Journals (Sweden)

Yared JA

2012-12-01

Full Text Available Jean A Yared, Katherine HR TkaczukUniversity of Maryland School of Medicine, Marlene and Stewart Greenebaum Cancer Center, Baltimore, MD, USAAbstract: The taxanes (paclitaxel and docetaxel represent an important class of antineoplastic agents that interfere with microtubule function leading to altered mitosis and cellular death. Paclitaxel (Taxol® was originally extracted from a yew tree (Taxus spp., Taxaceae a small slow-growing evergreen, coniferous tree. Due to the initial scarcity of paclitaxel, docetaxel (Taxotere® a semisynthetic analog of paclitaxel produced from the needles of European yew tree, Taxus baccata was developed. Docetaxel differs from paclitaxel in two positions in its chemical structure and this small alteration makes it more water soluble. Today, paclitaxel and docetaxel are widely prescribed antineoplastic agents for a broad range of malignancies including lung cancer, breast cancer, prostate cancer, Kaposi’s sarcoma, squamous cell carcinoma of the head and neck, gastric cancer, esophageal cancer, bladder cancer, and other carcinomas. Although very active clinically, paclitaxel and docetaxel have several clinical problems including poor drug solubility, serious dose-limiting toxicities such as myelosuppression, peripheral sensory neuropathy, allergic reactions, and eventual development of drug resistance. A number of these side effects have been associated with the solvents used for dilution of these antineoplastic agents: Cremophor EL for paclitaxel and polysorbate 80 for docetaxel. In addition, reports have linked these solvents to the alterations in paclitaxel and docetaxel pharmacokinetic profiles. In this review, we provide preclinical and clinical data on several novel taxanes formulations and analogs which are currently US Food and Drug Administration (FDA-approved or in clinical development in various solid tumor malignancies. Of the new taxanes nab-paclitaxel and cabazitaxel have enjoyed clinical success and

Comparison of Nootropic and Neuroprotective Features of Aryl-Substituted Analogs of Gamma-Aminobutyric Acid.

Science.gov (United States)

Tyurenkov, I N; Borodkina, L E; Bagmetova, V V; Berestovitskaya, V M; Vasil'eva, O S

2016-02-01

GABA analogs containing phenyl (phenibut) or para-chlorophenyl (baclofen) substituents demonstrated nootropic activity in a dose of 20 mg/kg: they improved passive avoidance conditioning, decelerated its natural extinction, and exerted antiamnestic effect on the models of amnesia provoked by scopolamine or electroshock. Tolyl-containing GABA analog (tolibut, 20 mg/kg) exhibited antiamnestic activity only on the model of electroshock-induced amnesia. Baclofen and, to a lesser extent, tolibut alleviated seizures provoked by electroshock, i.e. both agents exerted anticonvulsant effect. All examined GABA aryl derivatives demonstrated neuroprotective properties on the maximum electroshock model: they shortened the duration of coma and shortened the period of spontaneous motor activity recovery. In addition, these agents decreased the severity of passive avoidance amnesia and behavioral deficit in the open field test in rats exposed to electroshock. The greatest neuroprotective properties were exhibited by phenyl-containing GABA analog phenibut.

Data Provenance for Agent-Based Models in a Distributed Memory

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Delmar B. Davis

2018-04-01

Full Text Available Agent-Based Models (ABMs assist with studying emergent collective behavior of individual entities in social, biological, economic, network, and physical systems. Data provenance can support ABM by explaining individual agent behavior. However, there is no provenance support for ABMs in a distributed setting. The Multi-Agent Spatial Simulation (MASS library provides a framework for simulating ABMs at fine granularity, where agents and spatial data are shared application resources in a distributed memory. We introduce a novel approach to capture ABM provenance in a distributed memory, called ProvMASS. We evaluate our technique with traditional data provenance queries and performance measures. Our results indicate that a configurable approach can capture provenance that explains coordination of distributed shared resources, simulation logic, and agent behavior while limiting performance overhead. We also show the ability to support practical analyses (e.g., agent tracking and storage requirements for different capture configurations.

The roles of the analogy with natural selection in B.F. Skinner's philosophy.

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Smith, Terry L

2018-02-17

Beginning in the 1950s, B.F. Skinner made increasing reference to an analogy between operant conditioning and natural selection. This analogy is the basis of an argument that, in contrast to Skinner's other critiques of cognitive science, is neither epistemological nor pragmatic. Instead, it is based on the claim that ontogenetic adaptation is due to a special mode of causation he called "selection by consequences." He argued that this mode of causation conflicts with explanations that attribute action to an autonomous agent with reasons for acting. This argument dismisses ordinary explanations of action, and has implications not only for cognitive science but also for morals. Skinner cited the latter implications to counter objections to the application of behavior analysis to the reform of society and its institutions. Skinner's critique, however, rests upon empirical assumptions that have been criticized by other behavior analysts. Although for Skinner the major role of the analogy was to propose an empirical thesis, it also can play a metaphysical role-namely, to demonstrate the possibility of ontogenetic adaptation without reference to agents who have reasons for acting. These two roles, empirical and metaphysical, are the mirror image of the empirical and metaphysical roles of the computer analogy for cognitive science. That analogy also can be (and has been) interpreted as an empirical thesis. Its empirical implications, however, have been difficult to confirm. It also, however, has played a metaphysical role-namely, to demonstrate the possibility that a physical process could perform logical operations on states having propositional content. Neither analogy provides a well-confirmed, general answer to the question of how to explain the process of ontogenetic adaptation. But together they show there are two metaphysically coherent, but conflicting, answers to this question. Depending upon one's epistemology, the analogy with natural selection may provide a

Detecting analogical resemblance without retrieving the source analogy.

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Kostic, Bogdan; Cleary, Anne M; Severin, Kaye; Miller, Samuel W

2010-06-01

We examined whether people can detect analogical resemblance to an earlier experimental episode without being able to recall the experimental source of the analogical resemblance. We used four-word analogies (e.g., robin-nest/beaver-dam), in a variation of the recognition-without-cued-recall method (Cleary, 2004). Participants studied word pairs (e.g., robin-nest) and were shown new word pairs at test, half of which analogically related to studied word pairs (e.g., beaver-dam) and half of which did not. For each test pair, participants first attempted to recall an analogically similar pair from the study list. Then, regardless of whether successful recall occurred, participants were prompted to rate the familiarity of the test pair, which was said to indicate the likelihood that a pair that was analogically similar to the test pair had been studied. Across three experiments, participants demonstrated an ability to detect analogical resemblance without recalling the source analogy. Findings are discussed in terms of their potential relevance to the study of analogical reasoning and insight, as well as to the study of familiarity and recognition memory.

Security Infrastructure and Applicationsfor Mobile Agents

OpenAIRE

Shibli, Awais

2010-01-01

Research areas of this dissertation are security for mobile agents, for applications based on mobile agents, and for distributed network environments in which mobile agents execute. Mobile agents paradigm has captured researchers’ and industry’s interests long time ago because of its innovative capabilities and attractive applications. The ability of mobile agents to autonomously migrate from host to host, transferring their code and internal state, enables them to accomplish tasks in network...

Inhibitory Effects of Resveratrol Analogs on Mushroom Tyrosinase Activity

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Nádia Rezende Barbosa Raposo

2012-10-01

Full Text Available Skin pigmentation disorders typically involve an overproduction or uneven distribution of melanin, which results in skin spots. Resveratrol can inhibit tyrosinase, the active enzyme in the synthesis of melanin, but it does not inhibit the synthesis of melanin to an extent that enables its use alone as a skin whitening agent in pharmaceutical formulations, so its use as a coadjuvant in treatment of hyperpigmentation is suggested. Six resveratrol analogs were tested for tyrosinase inhibitory activity in vitro. Among the analogs tested, compound D was the most powerful tyrosinase inhibitor (IC50 = 28.66 µg/mL, two times more active than resveratrol (IC50 = 57.05 µg/mL, followed by the analogs A, E, B, F and C, respectively. This demonstrated that the hydroxylation at C4' on the phenolic ring was the molecular modification with most importance for the observed activity.

Boron neutron capture therapy. Synthesis of boronated amines- and DNA intercalating agents for potential use in cancer therapy

International Nuclear Information System (INIS)

Ghaneolhosseini, H.

1998-01-01

Boron Neutron Capture Therapy is a binary cancer treatment modality, involving the delivery of a suitable boron compound to tumour cells followed by irradiation of the tumour by thermal neutrons. Boronated agents can selectively be delivered to tumour cells either directly with tumour-specific boron compounds, or by use of targeting strategies. However, the efficacy of this method would increase if the boron agents are localised in the cell nucleus rather than in the cell cytoplasm when neutron irradiation takes place. With these considerations in mind, some boronated DNA intercalating/interacting agents such as phenanthridine- acridine- spermidine- and naphthalimide derivatives were synthesised. Aminoalkyl-o-carboranes were synthesised in order to be used both for coupling to macromolecules and also for halogenation of their corresponding nido-derivatives. The amino groups were introduced using the Gabriel reagent N, N-dibenzyl iminodicarboxylate to provide 1-(aminomethyl)- and 1-(2-aminoethyl)-o-carboranes. The first attempt to achieve the possibility to accumulate a higher concentration of boron atoms in the cell nucleus was to synthesize carboranyl phenanthridinium analogues by reacting a p- or o-carboranyl moiety with phenanthridine, a chromophore with a planar aromatic ring system as DNA intercalator. Boronated acridine-spermidine, boronated diacridine, and boronated dispermidine were obtained in order to increase water solubility to avoid the interaction of these agents with non-DNA sides of the cell, especially membranes; and to enhance the feasibility of a higher DNA-binding constant and also decrease the DNA-drug dissociation rate. Finally, the synthesis of a boronated naphthalimide derivative was carried out by nucleophilic reaction of a primary aminoalkyl-p-carborane with naphthalic anhydride. Biological evaluations on DNA-binding, toxicity, and cellular binding with carboranyl phenanthridinium analogues, boronated acridine- and spermidine are described

New insights into the synergism of nucleoside analogs with radiotherapy

International Nuclear Information System (INIS)

Lee, Michael W; Parker, William B; Xu, Bo

2013-01-01

Nucleoside analogs have been frequently used in combination with radiotherapy in the clinical setting, as it has long been understood that inhibition of DNA repair pathways is an important means by which many nucleoside analogs synergize. Recent advances in our understanding of the structure and function of deoxycytidine kinase (dCK), a critical enzyme required for the anti-tumor activity for many nucleoside analogs, have clarified the mechanistic role this kinase plays in chemo- and radio-sensitization. A heretofore unrecognized role of dCK in the DNA damage response and cell cycle machinery has helped explain the synergistic effect of these agents with radiotherapy. Since most currently employed nucleoside analogs are primarily activated by dCK, these findings lend fresh impetus to efforts focused on profiling and modulating dCK expression and activity in tumors. In this review we will briefly review the pharmacology and biochemistry of the major nucleoside analogs in clinical use that are activated by dCK. This will be followed by discussions of recent advances in our understanding of dCK activation via post-translational modifications in response to radiation and current strategies aimed at enhancing this activity in cancer cells

Identification of Novel 5,6-Dimethoxyindan-1-one Derivatives as Antiviral Agents.

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Patil, Siddappa A; Patil, Vikrant; Patil, Renukadevi; Beaman, Kenneth; Patil, Shivaputra A

2017-01-01

Discovery of novel antiviral agents is essential because viral infection continues to threaten human life globally. Various heterocyclic small molecules have been developed as antiviral agents. The 5,6-dimethoxyindan-1-on nucleus is of considerable interest as this ring is the key constituent in a range of bioactive compounds, both naturally occurring and synthetic, and often of considerable complexity. The main purpose of this research was to discover and develop small molecule heterocycles as broad-spectrum of antiviral agents. A focused small set of 5,6-dimethoxyindan-1-one analogs (6-8) along with a thiopene derivative (9) was screened for selected viruses (Vaccinia virus - VACA, Human papillomavirus - HPV, Zika virus - ZIKV, Dengue virus - DENV, Measles virus - MV, Poliovirus 3 - PV, Rift Valley fever virus - RVFV, Tacaribe virus - TCRV, Venezuelan equine encephalitis virus - VEEV, Herpes simplex virus 1 -HSV-1 and Human cytomegalovirus - HCMV) using the National Institute of Allergy and Infectious Diseases (NIAID)'s Division of Microbiology and Infectious Diseases (DMID) antiviral screening program. These molecules demonstrated moderate to excellent antiviral activity towards variety of viruses. The 5,6-dimethoxyindan-1-one analog (7) demonstrated high efficacy towards vaccinia virus (EC50: 30.00 µM) in secondary plaque reduction assay. The thiophene analog (9) has shown very good viral inhibition towards several viruses such as Human papillomavirus, Measles virus, Rift Valley fever virus, Tacaribe virus and Herpes simplex virus 1. Our research identified a novel 5,6-dimethoxyindan-1-one analog (compound 7), as a potent antiviral agent for vaccinia virus, and heterocyclic chalcone analog (compound 9) as a broad spectrum antiviral agent. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

9 CFR 121.3 - VS select agents and toxins.

Science.gov (United States)

2010-01-01

... genetically modified. (d) VS select agents or toxins that meet any of the following criteria are excluded from... AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS; ORGANISMS AND VECTORS POSSESSION, USE, AND... recombinant organisms: (1) Nucleic acids that can produce infectious forms of any of the select agent viruses...

Pharmacokinetics and pharmacodynamics of insulin analogs in special populations with type 2 diabetes mellitus

Directory of Open Access Journals (Sweden)

Morello CM

2011-12-01

Full Text Available Candis M Morello1,21Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, 2School of Pharmacy, University of California San Francisco, Veterans Affairs San Diego Healthcare System, San Diego, CA, USAIntroduction: The goal of insulin therapy in patients with either type 1 diabetes mellitus (T1DM or type 2 diabetes mellitus (T2DM is to match as closely as possible normal physiologic insulin secretion to control fasting and postprandial plasma glucose. Modifications of the insulin molecule have resulted in two long-acting insulin analogs (glargine and detemir and three rapid-acting insulins (aspart, lispro, and glulisine with improved pharmacokinetic/pharmacodynamic (PK/PD profiles. These agents can be used together in basal-bolus therapy to more closely mimic physiologic insulin secretion patterns.Methods: This study reviews effects of the multiple demographic and clinical parameters in the insulin analogs glargine, detemir, lispro, aspart, and glulisine in patients with T2DM. A search was conducted on PubMed for each major topic considered (effects of injection site, age, race/ethnicity, obesity, renal or hepatic dysfunction, pregnancy, exercise, drug interactions using the topic words and name of each type of insulin analog. Information was also obtained from the prescribing information for each insulin analog.Results: The PK/PD profiles for insulin analogs may be influenced by many variables including age, weight, and hepatic and renal function. However, these variables do not have equivalent effects on all long-acting or rapid-acting insulin analogs.Conclusion: Rapid-acting and long-acting insulin analogs represent major advances in treatment for patients with T2DM who require insulin therapy. However, there are potentially important PK and PD differences between the two long-acting agents and among the three rapid-acting insulin analogs, which should be considered when designing treatment regimens for

[History of the development of new vitamin D analogs for the treatment of renal failure, and future aspects].

Science.gov (United States)

Nishii, Yasuho

2002-06-01

In 1981, Suda and colleagues reported the new activity of calcitriol namely its ability to differentiate the myeloid leukemia cells into monocyte-macrophages. Several companies and organic chemists initiated the synthesis of vitamin D analogs with the aim to separate the calcemic actions of calcitriol from its actions on regulating the cell growth and differentiation. The group of Chugai company succeeded in marketing OCT, Oxarol, as a therapeutic agent for secondary hyperparathyroidism and psoriasis, and Leo company, MC903, Dovonex, as a drug for psoriasis. The work on OCT and MC903 vigorously stimulated research world-wide in the development of vitamin D analogs into pharmaceutical products. More new impressive vitamin D analogs are being developed. I am convinced that various vitamin D analogs will become highly effective therapeutic agents at the clinical level in the new century, and also that a new theory on the mechanism of vitamin D action will be generated.

Neutron capture therapy of epidermal growth factor (+) gliomas using boronated cetuximab (IMC-C225) as a delivery agent

Energy Technology Data Exchange (ETDEWEB)

Barth, Rolf F. E-mail: barth.1@osu.edu; Wu Gong; Yang Weilian; Binns, Peter J.; Riley, Kent J.; Patel, Hemant; Coderre, Jeffrey A.; Tjarks, Werner; Bandyopadhyaya, A.K.; Thirumamagal, B.T.S.; Ciesielski, Michael J.; Fenstermaker, Robert A

2004-11-01

Cetuximab (IMC-C225) is a monoclonal antibody directed against both the wild-type and mutant vIII isoform of the epidermal growth factor receptor (EGFR). The purpose of the present study was to evaluate the monoclonal antibody (MoAb), cetuximab, as a boron delivery agent for neutron capture therapy (NCT) of brain tumors. Twenty-four hours following intratumoral (i.t.) administration of boronated cetuximab (C225-G5-B{sub 1100}), the mean boron concentration in rats bearing either F98{sub EGFR} or F98{sub WT} gliomas were 92.3{+-}23.3 {mu}g/g and 36.5{+-}18.8 {mu}g/g, respectively. In contrast, the uptake of boronated dendrimer (G5-B{sub 1000}) was 6.7{+-}3.6 {mu}g/g. Based on its favorable in vivo uptake, C225-G5-B{sub 1100} was evaluated as a delivery agent for BNCT in F98{sub EGFR} glioma bearing rats. The mean survival time (MST) of rats that received C225-G5-B{sub 1100}, administered by convection enhanced delivery (CED), was 45{+-}3 d compared to 25{+-}3 d for untreated control animals. A further enhancement in MST to >59 d was obtained by administering C225-G5-B{sub 1100} in combination with i.v. boronophenylalanine (BPA). These data are the first to demonstrate the efficacy of a boronated MoAb for BNCT of an intracerebral (i.c.) glioma and are paradigmatic for future studies using a combination of boronated MoAbs and low molecular weight delivery agents.

Evaluation of a curcumin analog as an anti-cancer agent inducing ER stress-mediated apoptosis in non-small cell lung cancer cells

International Nuclear Information System (INIS)

Liu, Zhiguo; Wang, Yi; Sun, Yusheng; Ren, Luqing; Huang, Yi; Cai, Yuepiao; Weng, Qiaoyou; Shen, Xueqian; Li, Xiaokun; Liang, Guang

2013-01-01

Recent advances have highlighted the importance of the endoplasmic reticulum (ER) in cell death processes. Pharmacological interventions that effectively enhance tumor cell death through activating ER stress have attracted a great deal of attention for anti-cancer therapy. A bio-evaluation on 113 curcumin analogs against four cancer cell lines was performed through MTT assay. Furthermore, real time cell assay and flow cytometer were used to evaluate the apoptotic induction of (1E,4E)-1,5-bis(5-bromo-2-ethoxyphenyl)penta-1,4-dien-3-one (B82). Western blot, RT-qPCR, and siRNA were then utilized to confirm whether B82-induced apoptosis is mediated through activating ER stress pathway. Finally, the in vivo anti-tumor effect of B82 was evaluated. B82 exhibited strong anti-tumor activity in non-small cell lung cancer (NSCLC) H460 cells. Treatment with B82 significantly induced apoptosis in H460 cells in vitro and inhibited H460 tumor growth in vivo. Further studies demonstrated that the B82-induced apoptosis is mediated by activating ER stress both in vitro and in vivo. A new monocarbonyl analog of curcumin, B82, exhibited anti-tumor effects on H460 cells via an ER stress-mediated mechanism. B82 could be further explored as a potential anticancer agent for the treatment of NSCLC

Control of analog ferroelectric states by small dc-bias in conjunction with fluctuating waveforms

International Nuclear Information System (INIS)

Ricinschi, Dan; Okuyama, Masanori

2009-01-01

In this paper we demonstrate several possibilities to create and control partially switched analog states of ferroelectric materials, from measurements on PZT capacitors. By employing various types of fluctuating waveforms and controlling the domain dynamics with dc bias of small intensities, we have shown that it is possible to generate sequences of analog ferroelectric states that may appear identical from macroscopic measurements, yet they are unique at the local level. The experimental results have been analyzed theoretically by a simple microscopic model of switching. According to the model simulations, each analog state can be associated with a domain structure that captures subtle variations of the previously applied electric field as well as structural information about the inhomogeneities at the local level. The generation and control of such partially switched analog states may be important for new applications of ferroelectric materials to multi-value memories or in the field of artificial intelligence.

Synthesis and SAR studies of potent imidazopyridine anticoccidial agents.

Science.gov (United States)

Liang, Gui-Bai; Qian, Xiaoxia; Feng, Dennis; Fisher, Michael; Brown, Christine M; Gurnett, Anne; Leavitt, Penny Sue; Liberator, Paul A; Misura, Andrew S; Tamas, Tamas; Schmatz, Dennis M; Wyvratt, Matthew; Biftu, Tesfaye

2007-07-01

Diaryl imidazo[1,2-a]pyridine derivatives, such as 6a and 7i, have been synthesized and found to be potent inhibitors of parasite PKG activity. The most potent compounds are the 7-isopropylaminomethyl analog 6a and 2-isopropylamino analog 7i. These compounds are also fully active in in vivo assay as anticoccidial agents at 25 ppm in feed.

Analogical scaffolding: Making meaning in physics through representation and analogy

Science.gov (United States)

Podolefsky, Noah Solomon

This work reviews the literature on analogy, introduces a new model of analogy, and presents a series of experiments that test and confirm the utility of this model to describe and predict student learning in physics with analogy. Pilot studies demonstrate that representations (e.g., diagrams) can play a key role in students' use of analogy. A new model of analogy, Analogical Scaffolding, is developed to explain these initial empirical results. This model will be described in detail, and then applied to describe and predict the outcomes of further experiments. Two large-scale (N>100) studies will demonstrate that: (1) students taught with analogies, according to the Analogical Scaffolding model, outperform students taught without analogies on pre-post assessments focused on electromagnetic waves; (2) the representational forms used to teach with analogy can play a significant role in student learning, with students in one treatment group outperforming students in other treatment groups by factors of two or three. It will be demonstrated that Analogical Scaffolding can be used to predict these results, as well as finer-grained results such as the types of distracters students choose in different treatment groups, and to describe and analyze student reasoning in interviews. Abstraction in physics is reconsidered using Analogical Scaffolding. An operational definition of abstraction is developed within the Analogical Scaffolding framework and employed to explain (a) why physicists consider some ideas more abstract than others in physics, and (b) how students conceptions of these ideas can be modeled. This new approach to abstraction suggests novel approaches to curriculum design in physics using Analogical Scaffolding.

Preliminary studies of 99mTc labeled fatty acid analogs for myocardial imaging

International Nuclear Information System (INIS)

Guo Yuzhi; Kung, H.F.; Mack, R.H.

1988-01-01

Radio iodine labelled fatty acid analogs are potential myocardial imaging agents for SPECT. In this paper are reported three new 99m Tc labbeled fatty acid analogs: 9 '9 m Tc-BAT-TDA, 99m Tc-BAT-PDA and 99m Tc-BAT-H x DA. Ligand exchange reaction with 99m Tc stannous glucoheptonate in 50% aqueous ethanol is used for labelling. The yield of reactions is 87%, 70%, 49% respectively. 99m Tc-fatty acid is purified by extraction into chloroform and the purity as determined by reverse phase HPLC is 98%. In order to determine the structure of Tc-BAT-fatty acid, 99 Tc-BAT-PDA is synthesized with 99 Tc ammonium pertechnetate in 50% citric acid buffer (pH=6)/ethanol using stannous chloride as the reducing agent. 99 Tc-BAT-PDA displays the expected Tc=O UV absorption at 420nm and strong peak at 900cm -1 in the FTIR spectrum. Biodistribution studies of three 99m Tc-fatty acid analogs are conducted in rats using 125 I-ω- (p-iodophenyl) -penta-decanoic acid (IPPDA) as internal standard. The initial heart uptake of them is significantly lower than that of 125 I-IPPDA

Detecting analogies unconsciously

Directory of Open Access Journals (Sweden)

Thomas Peter Reber

2014-01-01

Full Text Available Analogies may arise from the conscious detection of similarities between a present and a past situation. In this functional magnetic resonance imaging study, we tested whether young volunteers would detect analogies unconsciously between a current supraliminal (visible and a past subliminal (invisible situation. The subliminal encoding of the past situation precludes awareness of analogy detection in the current situation. First, participants encoded subliminal pairs of unrelated words in either one or nine encoding trials. Later, they judged the semantic fit of supraliminally presented new words that either retained a previously encoded semantic relation (‘analog’ or not (‘broken analog’. Words in analogs versus broken analogs were judged closer semantically, which reflects unconscious analogy detection. Hippocampal activity associated with subliminal encoding correlated with the behavioral measure of unconscious analogy detection. Analogs versus broken analogs were processed with reduced prefrontal but enhanced medial temporal activity. We conclude that analogous episodes can be detected even unconsciously drawing on the episodic memory network.

Analogy in causal inference: rethinking Austin Bradford Hill's neglected consideration.

Science.gov (United States)

Weed, Douglas L

2018-05-01

The purpose of this article was to rethink and resurrect Austin Bradford Hill's "criterion" of analogy as an important consideration in causal inference. In epidemiology today, analogy is either completely ignored (e.g., in many textbooks), or equated with biologic plausibility or coherence, or aligned with the scientist's imagination. None of these examples, however, captures Hill's description of analogy. His words suggest that there may be something gained by contrasting two bodies of evidence, one from an established causal relationship, the other not. Coupled with developments in the methods of systematic assessments of evidence-including but not limited to meta-analysis-analogy can be restructured as a key component in causal inference. This new approach will require that a collection-a library-of known cases of causal inference (i.e., bodies of evidence involving established causal relationships) be developed. This library would likely include causal assessments by organizations such as the International Agency for Research on Cancer, the National Toxicology Program, and the United States Environmental Protection Agency. In addition, a process for describing key features of a causal relationship would need to be developed along with what will be considered paradigm cases of causation. Finally, it will be important to develop ways to objectively compare a "new" body of evidence with the relevant paradigm case of causation. Analogy, along with all other existing methods and causal considerations, may improve our ability to identify causal relationships. Copyright © 2018 Elsevier Inc. All rights reserved.

Accumulation of MRI contrast agents in malignant fibrous histiocytoma for gadolinium neutron capture therapy

International Nuclear Information System (INIS)

Fujimoto, T.; Ichikawa, H.; Akisue, T.; Fujita, I.; Kishimoto, K.; Hara, H.; Imabori, M.; Kawamitsu, H.; Sharma, P.; Brown, S.C.; Moudgil, B.M.; Fujii, M.; Yamamoto, T.; Kurosaka, M.; Fukumori, Y.

2009-01-01

Neutron-capture therapy with gadolinium (Gd-NCT) has therapeutic potential, especially that gadolinium is generally used as a contrast medium in magnetic resonance imaging (MRI). The accumulation of gadolinium in a human sarcoma cell line, malignant fibrosis histiocytoma (MFH) Nara-H, was visualized by the MRI system. The commercially available MRI contrast medium Gd-DTPA (Magnevist, dimeglumine gadopentetate aqueous solution) and the biodegradable and highly gadopentetic acid (Gd-DTPA)-loaded chitosan nanoparticles (Gd-nanoCPs) were prepared as MRI contrast agents. The MFH cells were cultured and collected into three falcon tubes that were set into the 3-tesra MRI system to acquire signal intensities from each pellet by the spin echo method, and the longitudinal relaxation time (T1) was calculated. The amount of Gd in the sample was measured by inductively coupled plasma atomic emission spectrography (ICP-AES). The accumulation of gadolinium in cells treated with Gd-nanoCPs was larger than that in cells treated with Gd-DTPA. In contrast, and compared with the control, Gd-DTPA was more effective than Gd-nanoCPs in reducing T1, suggesting that the larger accumulation exerted the adverse effect of lowering the enhancement of MRI. Further studies are warranted to gain insight into the therapeutic potential of Gd-NCT.

Automatic activation of categorical and abstract analogical relations in analogical reasoning.

Science.gov (United States)

Green, Adam E; Fugelsang, Jonathan A; Dunbar, Kevin N

2006-10-01

We examined activation of concepts during analogical reasoning. Subjects made either analogical judgments or categorical judgments about four-word sets. After each four-word set, they named the ink color of a single word in a modified Stroop task. Words that referred to category relations were primed (as indicated by longer response times on Stroop color naming) subsequent to analogical judgments and categorical judgments. This finding suggests that activation of category concepts plays a fundamental role in analogical thinking. When colored words referred to analogical relations, priming occurred subsequent to analogical judgments, but not to categorical judgments, even though identical four-word stimuli were used for both types of judgments. This finding lends empirical support to the hypothesis that, when people comprehend the analogy between two items, they activate an abstract analogical relation that is distinct from the specific content items that compose the analogy.

Synthesis and antimicrobial properties of 1,3,4-oxadiazole analogs containing dibenzosuberone moiety

Energy Technology Data Exchange (ETDEWEB)

Moger, Manjunath [Mangalore University, Karnataka (India). Department of Chemistry; Satam, Vijay; Paniraj, A.S.; Gopinath, Vadiraj S.; Hindupur, Rama Mohan; Pati, Hari N., E-mail: hari.pati@advinus.com [Advinus Therapeutics Ltd., 21 and 22, Phase II, Peenya Industrial Area, Karnataka (India); Govindaraju, Darshan Raj C. [Department of Bio-Medicinal Research, Vidya Herbs Pvt. Ltd., Karnataka (India)

2014-01-15

A series of ten novel 1,3,4-oxadiazole analogs containing dibenzosuberone moiety were synthesized using linear as well as convergent synthesis approach. All the compounds were characterized by mass spectrometry, infrared (IR), {sup 1}H and {sup 13}C nuclear magnetic resonance ({sup 1}H NMR and {sup 13}C NMR) spectroscopies and elemental analysis. These compounds were evaluated for antibacterial and antifungal activities. Among ten analogs, four compounds, namely, 8a, 8d, 8e and 8j were found to be highly active antibacterial and antifungal agents (author)

Analog computing

CERN Document Server

Ulmann, Bernd

2013-01-01

This book is a comprehensive introduction to analog computing. As most textbooks about this powerful computing paradigm date back to the 1960s and 1970s, it fills a void and forges a bridge from the early days of analog computing to future applications. The idea of analog computing is not new. In fact, this computing paradigm is nearly forgotten, although it offers a path to both high-speed and low-power computing, which are in even more demand now than they were back in the heyday of electronic analog computers.

The First Synthesis and Anti-retroviral Activity of 5',5'-Difluoro-3'-Hydroxy-Apiosyl Nucleoside Cyclomonophosphonic Acid Analogs

Energy Technology Data Exchange (ETDEWEB)

Kim, Seyeon; Hong, Joon Hee [Chosun University, Gwangju (Korea, Republic of)

2016-04-15

The first synthesis of novel 5',5'-difluoro-30-hydroxy apiose nucleoside cyclomonophosphonic acid analogs was performed as potent anti-retroviral agents. Phosphonation was performed by direct displacement of a triflate intermediate with diethyl(lithiodifluoromethyl) phosphonate to give the corresponding(α, α-difluoroalkyl) phosphonate. Condensation successfully proceeded from a glycosyl donor with persilylated bases to yield the nucleoside phosphonate analogs. Deprotection of diethyl phosphonates provided the target nucleoside cyclomonophosphonic acid analogs. The synthesized nucleoside analogs were subjected to anti-viral screening against the human immunodeficiency virus-1 (HIV-1). Cytosine analogs show significant anti-HIV activity.

General Video Game AI: Learning from Screen Capture

OpenAIRE

Kunanusont, Kamolwan; Lucas, Simon M.; Perez-Liebana, Diego

2017-01-01

General Video Game Artificial Intelligence is a general game playing framework for Artificial General Intelligence research in the video-games domain. In this paper, we propose for the first time a screen capture learning agent for General Video Game AI framework. A Deep Q-Network algorithm was applied and improved to develop an agent capable of learning to play different games in the framework. After testing this algorithm using various games of different categories and difficulty levels, th...

Science Teachers' Analogical Reasoning

Science.gov (United States)

Mozzer, Nilmara Braga; Justi, Rosária

2013-08-01

Analogies can play a relevant role in students' learning. However, for the effective use of analogies, teachers should not only have a well-prepared repertoire of validated analogies, which could serve as bridges between the students' prior knowledge and the scientific knowledge they desire them to understand, but also know how to introduce analogies in their lessons. Both aspects have been discussed in the literature in the last few decades. However, almost nothing is known about how teachers draw their own analogies for instructional purposes or, in other words, about how they reason analogically when planning and conducting teaching. This is the focus of this paper. Six secondary teachers were individually interviewed; the aim was to characterize how they perform each of the analogical reasoning subprocesses, as well as to identify their views on analogies and their use in science teaching. The results were analyzed by considering elements of both theories about analogical reasoning: the structural mapping proposed by Gentner and the analogical mechanism described by Vosniadou. A comprehensive discussion of our results makes it evident that teachers' content knowledge on scientific topics and on analogies as well as their pedagogical content knowledge on the use of analogies influence all their analogical reasoning subprocesses. Our results also point to the need for improving teachers' knowledge about analogies and their ability to perform analogical reasoning.

Coherent time-stretch transformation for real-time capture of wideband signals.

Science.gov (United States)

Buckley, Brandon W; Madni, Asad M; Jalali, Bahram

2013-09-09

Time stretch transformation of wideband waveforms boosts the performance of analog-to-digital converters and digital signal processors by slowing down analog electrical signals before digitization. The transform is based on dispersive Fourier transformation implemented in the optical domain. A coherent receiver would be ideal for capturing the time-stretched optical signal. Coherent receivers offer improved sensitivity, allow for digital cancellation of dispersion-induced impairments and optical nonlinearities, and enable decoding of phase-modulated optical data formats. Because time-stretch uses a chirped broadband (>1 THz) optical carrier, a new coherent detection technique is required. In this paper, we introduce and demonstrate coherent time stretch transformation; a technique that combines dispersive Fourier transform with optically broadband coherent detection.

Analog synthetic biology.

Science.gov (United States)

Sarpeshkar, R

2014-03-28

We analyse the pros and cons of analog versus digital computation in living cells. Our analysis is based on fundamental laws of noise in gene and protein expression, which set limits on the energy, time, space, molecular count and part-count resources needed to compute at a given level of precision. We conclude that analog computation is significantly more efficient in its use of resources than deterministic digital computation even at relatively high levels of precision in the cell. Based on this analysis, we conclude that synthetic biology must use analog, collective analog, probabilistic and hybrid analog-digital computational approaches; otherwise, even relatively simple synthetic computations in cells such as addition will exceed energy and molecular-count budgets. We present schematics for efficiently representing analog DNA-protein computation in cells. Analog electronic flow in subthreshold transistors and analog molecular flux in chemical reactions obey Boltzmann exponential laws of thermodynamics and are described by astoundingly similar logarithmic electrochemical potentials. Therefore, cytomorphic circuits can help to map circuit designs between electronic and biochemical domains. We review recent work that uses positive-feedback linearization circuits to architect wide-dynamic-range logarithmic analog computation in Escherichia coli using three transcription factors, nearly two orders of magnitude more efficient in parts than prior digital implementations.

Neutron capture therapy for melanoma

Energy Technology Data Exchange (ETDEWEB)

Coderre, J.A.; Glass, J.D.; Micca, P.; Fairchild, R.G.

1988-01-01

The development of boron-containing compounds which localize selectively in tumor may require a tumor-by-tumor type of approach that exploits any metabolic pathways unique to the particular type of tumor. Melanin-producing melanomas actively transport and metabolize aromatic amino acids for use as precursors in the synthesis of the pigment melanin. It has been shown that the boron-containing amino acid analog p-borono-phenylalanine (BPA) is selectively accumulated in melanoma tissue, producing boron concentrations in tumor that are within the range estimated to be necessary for successful boron neutron capture therapy (BNCT). We report here the results of therapy experiments carried out at the Brookhaven Medical Research Reactor (BMRR). 21 refs., 5 figs., 3 tabs.

Neutron capture therapy for melanoma

International Nuclear Information System (INIS)

Coderre, J.A.; Glass, J.D.; Micca, P.; Fairchild, R.G.

1988-01-01

The development of boron-containing compounds which localize selectively in tumor may require a tumor-by-tumor type of approach that exploits any metabolic pathways unique to the particular type of tumor. Melanin-producing melanomas actively transport and metabolize aromatic amino acids for use as precursors in the synthesis of the pigment melanin. It has been shown that the boron-containing amino acid analog p-borono-phenylalanine (BPA) is selectively accumulated in melanoma tissue, producing boron concentrations in tumor that are within the range estimated to be necessary for successful boron neutron capture therapy (BNCT). We report here the results of therapy experiments carried out at the Brookhaven Medical Research Reactor (BMRR). 21 refs., 5 figs., 3 tabs

Near-term deployment of carbon capture and sequestration from biorefineries in the United States.

Science.gov (United States)

Sanchez, Daniel L; Johnson, Nils; McCoy, Sean T; Turner, Peter A; Mach, Katharine J

2018-05-08

Capture and permanent geologic sequestration of biogenic CO 2 emissions may provide critical flexibility in ambitious climate change mitigation. However, most bioenergy with carbon capture and sequestration (BECCS) technologies are technically immature or commercially unavailable. Here, we evaluate low-cost, commercially ready CO 2 capture opportunities for existing ethanol biorefineries in the United States. The analysis combines process engineering, spatial optimization, and lifecycle assessment to consider the technical, economic, and institutional feasibility of near-term carbon capture and sequestration (CCS). Our modeling framework evaluates least cost source-sink relationships and aggregation opportunities for pipeline transport, which can cost-effectively transport small CO 2 volumes to suitable sequestration sites; 216 existing US biorefineries emit 45 Mt CO 2 annually from fermentation, of which 60% could be captured and compressed for pipeline transport for under $25/tCO 2 A sequestration credit, analogous to existing CCS tax credits, of $60/tCO 2 could incent 30 Mt of sequestration and 6,900 km of pipeline infrastructure across the United States. Similarly, a carbon abatement credit, analogous to existing tradeable CO 2 credits, of $90/tCO 2 can incent 38 Mt of abatement. Aggregation of CO 2 sources enables cost-effective long-distance pipeline transport to distant sequestration sites. Financial incentives under the low-carbon fuel standard in California and recent revisions to existing federal tax credits suggest a substantial near-term opportunity to permanently sequester biogenic CO 2 This financial opportunity could catalyze the growth of carbon capture, transport, and sequestration; improve the lifecycle impacts of conventional biofuels; support development of carbon-negative fuels; and help fulfill the mandates of low-carbon fuel policies across the United States. Copyright © 2018 the Author(s). Published by PNAS.

Removal of Hg(II) from aqueous solution using sodium humate as heavy metal capturing agent.

Science.gov (United States)

Wang, Shixiang; Liu, Yong; Fan, Qin; Zhou, Anlan; Fan, Lu; Mu, Yulan

2016-12-01

An environmental friendly and economic natural biopolymer-sodium humate (HA-Na) was used to capture Hg(II) from aqueous solutions, and the trapped Hg(II) (HA-Na-Hg) was then removed by aluminium coagulation. The best Hg(II) capturing performance (90.60%) was observed under the following conditions: initial pH of 7.0, coagulation pH of 6.0, HA-Na dosage of 5.0 g L -1 , Al 2 (SO 4 ) 3 .18H 2 O dosage of 4.0 g L -1 , initial Hg(II) concentration of 50 mg L -1 and capturing time of 30 min. The HA-Na compositions with the molecular weight beyond 70 kDa showed the most intense affinity toward Hg(II). The results showed that the reaction equilibrium was achieved within 10 min (pH 7.0), and could be well fitted by the pseudo-second-order kinetics model. The capturing process could be well described by the Langmuir isotherm model and the maximum capturing capacity of Hg(II) was high up to 9.80 mg g -1 at 298 K (pH 7.0). The Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) analysis showed that the redox reaction between Hg(II) and HA-Na and the coordination reaction of carboxyl and hydroxy groups of HA-Na with Hg(II) were responsible for Hg(II) removal. The successive regeneration experiment showed that the capturing efficiency of humates for Hg(II) was maintained at about 51% after five capture-regeneration recycles.

Controlled dual release study of curcumin and a 4-aminoquinoline analog from gum acacia containing hydrogels

CSIR Research Space (South Africa)

Aderibigbe, BA

2014-10-01

Full Text Available The potential of gum acacia containing hydrogels as controlled dual-drug delivery systems for antiprotozoal agents was investigated. 4-Aminoquinoline analog and curcumin were selected as model drugs because they exhibit antiprotozoal activity...

Rhetoric and analogies

OpenAIRE

Aragonès, Enriqueta; Gilboa, Itzhak; Postlewaite, Andrew; Schmeidler, David; Universitat Autònoma de Barcelona. Unitat de Fonaments de l'Anàlisi Econòmica; Universitat Autònoma de Barcelona. Institut d'Anàlisi Econòmica

2013-01-01

The art of rhetoric may be defined as changing other people's minds (opinions, beliefs) without providing them new information. One tech- nique heavily used by rhetoric employs analogies. Using analogies, one may draw the listener's attention to similarities between cases and to re-organize existing information in a way that highlights certain reg- ularities. In this paper we offer two models of analogies, discuss their theoretical equivalence, and show that finding good analogies is a com- p...

Assessment of the role of micropore size and N-doping in CO2 capture by porous carbons.

Science.gov (United States)

Sevilla, Marta; Parra, Jose B; Fuertes, Antonio B

2013-07-10

The role of micropore size and N-doping in CO2 capture by microporous carbons has been investigated by analyzing the CO2 adsorption properties of two types of activated carbons with analogous textural properties: (a) N-free carbon microspheres and (b) N-doped carbon microspheres. Both materials exhibit a porosity made up exclusively of micropores ranging in size between micropores with a size below 0.8 nm. It was also observed that the CO2 capture capacities of undoped and N-doped carbons are analogous which shows that the nitrogen functionalities present in these N-doped samples do not influence CO2 adsorption. Taking into account the temperature invariance of the characteristic curve postulated by the Dubinin theory, we show that CO2 uptakes can be accurately predicted by using the adsorption data measured at just one temperature.

Multi-Agent Framework in Visual Sensor Networks

Directory of Open Access Journals (Sweden)

J. M. Molina

2007-01-01

Full Text Available The recent interest in the surveillance of public, military, and commercial scenarios is increasing the need to develop and deploy intelligent and/or automated distributed visual surveillance systems. Many applications based on distributed resources use the so-called software agent technology. In this paper, a multi-agent framework is applied to coordinate videocamera-based surveillance. The ability to coordinate agents improves the global image and task distribution efficiency. In our proposal, a software agent is embedded in each camera and controls the capture parameters. Then coordination is based on the exchange of high-level messages among agents. Agents use an internal symbolic model to interpret the current situation from the messages from all other agents to improve global coordination.

Intuitive analog circuit design

CERN Document Server

Thompson, Marc

2013-01-01

Intuitive Analog Circuit Design outlines ways of thinking about analog circuits and systems that let you develop a feel for what a good, working analog circuit design should be. This book reflects author Marc Thompson's 30 years of experience designing analog and power electronics circuits and teaching graduate-level analog circuit design, and is the ideal reference for anyone who needs a straightforward introduction to the subject. In this book, Dr. Thompson describes intuitive and ""back-of-the-envelope"" techniques for designing and analyzing analog circuits, including transistor amplifi

Design, synthesis and biological evaluation of novel desmuramyldipeptide analogs.

Science.gov (United States)

Jakopin, Žiga; Corsini, Emanuela; Gobec, Martina; Mlinarič-Raščan, Irena; Dolenc, Marija Sollner

2011-09-01

A series of novel desmuramyldipeptides have been designed and synthesized as part of our search for therapeutically useful muramyldipeptide (MDP) analogs. Their immunomodulatory properties were initially assessed in vitro, evaluating their effect on lipopolysaccharide (LPS)-induced cytokine release in THP-1 cells. Following the initial screening, selected compounds were further investigated for immunomodulatory properties using LPS and phorbol 12-myristate 13-acetate (PMA)/ionomycin-stimulated human peripheral blood mononuclear cells. The results confirmed the immunomodulatory properties of some of the synthesized desmuramyldipeptide analogs. Taken together, presented data confirmed the immunostimulatory effect of compound 44, MDP derivative incorporating a pyrido-fused [1,2]-benzisothiazole moiety, while for compounds 32 and 39, indole scaffold-based derivatives of MDP, an immunosuppressive effect was observed. Further studies will be necessary to address their potential therapeutic use as immunomodulatory drugs, both as immunostimulants or anti-inflammatory agents. Copyright © 2011 Elsevier Masson SAS. All rights reserved.

Computational design of new molecular scaffolds for medicinal chemistry, part II: generalization of analog series-based scaffolds

Science.gov (United States)

Dimova, Dilyana; Stumpfe, Dagmar; Bajorath, Jürgen

2018-01-01

Aim: Extending and generalizing the computational concept of analog series-based (ASB) scaffolds. Materials & methods: Methodological modifications were introduced to further increase the coverage of analog series (ASs) and compounds by ASB scaffolds. From bioactive compounds, ASs were systematically extracted and second-generation ASB scaffolds isolated. Results: More than 20,000 second-generation ASB scaffolds with single or multiple substitution sites were extracted from active compounds, achieving more than 90% coverage of ASs. Conclusion: Generalization of the ASB scaffold approach has yielded a large knowledge base of scaffold-capturing compound series and target information. PMID:29379641

In Defense of Agent-Based Virtue Ethics | Van Zyl | Philosophical ...

African Journals Online (AJOL)

In 'Against agent-based virtue ethics' (2004) Michael Brady rejects agent-based virtue ethics on the grounds that it fails to capture the commonsense distinction between an agent's doing the right thing, and her doing it for the right reason. In his view, the failure to account for this distinction has paradoxical results, making it ...

New carbon-carbon linked amphiphilic carboranyl-porphyrins as boron neutron capture agents

International Nuclear Information System (INIS)

Vicente, M.G.H.; Wickramasinghe, A.; Shetty, S.J.; Smith, K.M.

2000-01-01

Novel amphiphilic carboranyl-porphyrins have been synthesized for Boron Neutron Capture Therapy (BNCT). These compounds have carbon-carbon bonds between the carborane residues and the porphyrin meso-phenyl groups, and contain 28-31% boron by weight . (author)

High-speed and high-resolution analog-to-digital and digital-to-analog converters

NARCIS (Netherlands)

van de Plassche, R.J.

1989-01-01

Analog-to-digital and digital-to-analog converters are important building blocks connecting the analog world of transducers with the digital world of computing, signal processing and data acquisition systems. In chapter two the converter as part of a system is described. Requirements of analog

Preclinical evaluation of neurotensin(8-13) analog radiolabeled with 99mTc: in vitro and in vivo characterization

International Nuclear Information System (INIS)

Teodoro, Rodrigo

2010-01-01

The radiolabeling of receptor specific biomolecules with 99m Tc using bifunctional chelator agents represents a growing field in Nuclear Medicine, specially, regarding regulatory peptides, such as Neurotensin, which are important in several essential physiological functions, particularly in tumor growth. The aim of the study was the comparative radiolabeling evaluation of the double-stabilized NT(8-13) analog with 99m Tc, via the bifunctional chelating agents 6- hydrazinonicotinamide (HYNIC) and S-acetyl-mercaptoacetyltriglycine (MAG3) in MDA-MB-231 breast cancer cell line. High radiochemical yields (> 97%) and stability toward transchelant agents was observed for both radiolabeled analogs. Also, comparable in vitro behaviour regarding the percentage of plasma protein binding (nearby 22%), metabolic stability, receptor binding affinity (nM range), and internalization/externalization rates were obtained. The greater lipophilicity found for the analog radiolabeled via MAG 3 , reflected in the major differences in biodistribution studies. The in vivo metabolic stability studies suggested that the degradation observed in the later time point (90 min) for the conjugate radiolabeled via HYNIC, leads not only to lower tumor uptake accumulation (0,44±0,02% ID/g), but also to lower tumor-to-non-tumor ratios ( 3 had been confirmed in the present study, a structural re-design aiming the reduction of the high gastrointestinal uptake must be done in order to guarantee the potential applicability of MAG 3 -radio complex. (author)

9 CFR 121.4 - Overlap select agents and toxins.

Science.gov (United States)

2010-01-01

... in paragraph (b) of this section that have been genetically modified. (d) Overlap select agents or... OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS; ORGANISMS AND VECTORS POSSESSION, USE... elements, recombinant nucleic acids, and recombinant organisms: (1) Nucleic acids that can produce...

Lab scale testing of novel natural analog in situ stabilization agents

International Nuclear Information System (INIS)

Shaw, P.

1997-01-01

This report summarizes the laboratory-scale test results on several novel in situ treatment and stabilization agents for buried hazardous and radioactive waste. Paraffin, hematite and phosphate materials were examined when combined with soil and other wastes representative of what might be present at buried waste DOE sites. Hematite was made from the reaction of agricultural iron and lime slurries to form gypsum and iron oxide/hydroxide. Common household paraffin was melted, both with and without a zeolitic additive, waste added and then cooled. Magnesium phosphate was made from the reaction of magnesium oxide and phosphoric acid or potassium biphosphate to form, magnesium phosphate. All were tested with soil and some with additional waste sumulants such as ash, machine oil and nitrate salts. The following laboratory-generated data indicate that all waste encapsulation materials tested are appropriate materials, for field in situ testing. Compressive strengths of treated Idaho National Engineering and Environment Laboratory (INEEL) soil and the waste encapsulation material were sufficient to prevent collapse of the void space in waste, i.e., greater than the NRC 60 psi minimum. The mineralogy and microstructure of hematite was amorphous but should progress to an interlocking crystalline solid. Phosphate was crystalline with characteristics of higher temperature ceramics. Paraffin is non crystalline but encapsulates even very fine grained INEEL soils. Each agent appears to be chemically and physically inert to possible waste materials such as, nitrates and machine cutting oil. Two of the agents hematite and phosphate react favorably with ash increasing the metals retention at higher waste loadings than Portland cement. Hematite, phosphate and zeolite decrease leaching of most hazardous metals from waste when compared to untreated waste and soil. Solution pH, time for reaction initiation, and viscosity values are conducive to jet-grouting application

Agent Communications using Distributed Metaobjects

Energy Technology Data Exchange (ETDEWEB)

Goldsmith, Steven Y.; Spires, Shannon V.

1999-06-10

There are currently two proposed standards for agent communication languages, namely, KQML (Finin, Lobrou, and Mayfield 1994) and the FIPA ACL. Neither standard has yet achieved primacy, and neither has been evaluated extensively in an open environment such as the Internet. It seems prudent therefore to design a general-purpose agent communications facility for new agent architectures that is flexible yet provides an architecture that accepts many different specializations. In this paper we exhibit the salient features of an agent communications architecture based on distributed metaobjects. This architecture captures design commitments at a metaobject level, leaving the base-level design and implementation up to the agent developer. The scope of the metamodel is broad enough to accommodate many different communication protocols, interaction protocols, and knowledge sharing regimes through extensions to the metaobject framework. We conclude that with a powerful distributed object substrate that supports metaobject communications, a general framework can be developed that will effectively enable different approaches to agent communications in the same agent system. We have implemented a KQML-based communications protocol and have several special-purpose interaction protocols under development.

An analog memory integrated circuit for waveform sampling up to 900 MHz

International Nuclear Information System (INIS)

Haller, G.M.; Wooley, B.A.

1994-01-01

The potential of switched-capacitor technology for acquiring analog signals in high-energy physics (HEP) applications has been demonstrated in a number of analog memory designs. The design and implementation of a switched-capacitor memory suitable for capturing high-speed analog waveforms is described. Highlights of the presented circuit are a 900 MHz sampling frequency (generated on chip), input signal independent cell pedestal and sampling instances, and cell gains that are insensitive to component sizes. A two-channel version of the memory with 32 cells for each channel has been integrate in a 2-μm complementary metal oxide semiconductor (CMOS) process with polysilicon-to-polysilicon capacitors. The measured rms cell response variation in a channel after cell pedestal subtraction is less than 0.3 mV across the full input signal range. The cell-to-cell gain matching is better than 0.01% rms, and the nonlinearity is less than 0.03% for a 2.5-V input range. The dynamic range of the memory exceeds 13 bits, and the peak signal-to-(noise + distortion) ratio for a 21.4 MHz sine wave sampled at 900 MHz is 59 dB

Structured Analog CMOS Design

CERN Document Server

Stefanovic, Danica

2008-01-01

Structured Analog CMOS Design describes a structured analog design approach that makes it possible to simplify complex analog design problems and develop a design strategy that can be used for the design of large number of analog cells. It intentionally avoids treating the analog design as a mathematical problem, developing a design procedure based on the understanding of device physics and approximations that give insight into parameter interdependences. The proposed transistor-level design procedure is based on the EKV modeling approach and relies on the device inversion level as a fundament

Analog and hybrid computing

CERN Document Server

Hyndman, D E

2013-01-01

Analog and Hybrid Computing focuses on the operations of analog and hybrid computers. The book first outlines the history of computing devices that influenced the creation of analog and digital computers. The types of problems to be solved on computers, computing systems, and digital computers are discussed. The text looks at the theory and operation of electronic analog computers, including linear and non-linear computing units and use of analog computers as operational amplifiers. The monograph examines the preparation of problems to be deciphered on computers. Flow diagrams, methods of ampl

Effects of inlet/outlet configurations on the electrostatic capture of airborne nanoparticles and viruses

International Nuclear Information System (INIS)

Jang, Jaesung; Akin, Demir; Bashir, Rashid

2008-01-01

Motivated by capture and detection of airborne biological agents in real time with a cantilever biosensor without introducing the agents into liquids, we present the effects of inlet/outlet configurations of a homemade particle collector on the electrostatic capture of airborne 100 nm diameter nanoparticles under swirling gas flows. This particle collector has three different inlet/outlet configurations: forward inlet/outlet (FO), backward inlet/outlet (BO) and straight inlet/outlet (SO) configurations. We also present the electrostatic capture of Vaccinia viruses using the same particle collector and compare these virus measurements with the nanoparticle cases. The most particles were collected in the FO configuration. The numbers of particles captured in the BO and SO configurations were close within their standard deviations. For all the three configurations tested, the number of particles captured in the center electrode C was much smaller than those captured in the other electrodes at a flow rate of 1.1 l min −1 and an applied potential of 2 kV. Using a commercial CFD code FLUENT, we also simulated the effects of the three inlet/outlet configurations on the particle capture in terms of particle trajectories, velocities and travel times. This simulation was in a good agreement with measurements that the FO configuration is the most favorable to particle capture among the tested configurations at a flow rate of 1.1 l min −1 . The effects of particle diameters on the capture will also be discussed. This collector can be used for real-time monitoring of bioaerosols along with cantilever biosensors

Analog-to-digital conversion

CERN Document Server

Pelgrom, Marcel J M

2010-01-01

The design of an analog-to-digital converter or digital-to-analog converter is one of the most fascinating tasks in micro-electronics. In a converter the analog world with all its intricacies meets the realm of the formal digital abstraction. Both disciplines must be understood for an optimum conversion solution. In a converter also system challenges meet technology opportunities. Modern systems rely on analog-to-digital converters as an essential part of the complex chain to access the physical world. And processors need the ultimate performance of digital-to-analog converters to present the results of their complex algorithms. The same progress in CMOS technology that enables these VLSI digital systems creates new challenges for analog-to-digital converters: lower signal swings, less power and variability issues. Last but not least, the analog-to-digital converter must follow the cost reduction trend. These changing boundary conditions require micro-electronics engineers to consider their design choices for...

Results of Study of Sulfur Oxide Reduction During Combustion of Coal-Water Slurry Fuel Through use of Sulfur Capturing Agents

Directory of Open Access Journals (Sweden)

Murko Vasiliy I.

2016-01-01

Full Text Available It is shown that an effective way of burning high sulfur coal is to burn coal-water slurry fuel (CWF prepared on its basis containing a sulfur capture agent (SCA entered in the slurry at the stage of preparation. The technique of thermodynamic analysis of chemical reactions during CWF burning has been developed including burning in the presence of SCA. Using the developed calculation program, the optimal temperature conditions have been determined as required for the effective reduction of sulfur oxides in flue gases when using different types of SCA. According to the results of calculating the composition of CWF combustion products when entering various substances in the burner space as SCA it has been determined that magnesite, calcite, and dolomite are the most effective natural minerals. The analysis of calculated and experimental data proves the efficiency of SCA addition as well as validity of the obtained results.

Virtual Gamma Ray Radiation Sources through Neutron Radiative Capture

Energy Technology Data Exchange (ETDEWEB)

Scott Wilde, Raymond Keegan

2008-07-01

The countrate response of a gamma spectrometry system from a neutron radiation source behind a plane of moderating material doped with a nuclide of a large radiative neutron capture cross-section exhibits a countrate response analogous to a gamma radiation source at the same position from the detector. Using a planar, surface area of the neutron moderating material exposed to the neutron radiation produces a larger area under the prompt gamma ray peak in the detector than a smaller area of dimensions relative to the active volume of the gamma detection system.

Synthesis and Antitumor Activity of Triazole-Containing Sorafenib Analogs

Directory of Open Access Journals (Sweden)

Wenjing Ye

2017-10-01

Full Text Available Using a highly effective binuclear Cu complex as the catalyst, the 1,3-dipolar cycloaddition reactions between 16 alkynes and two azides were successfully performed and resulted in the production of 25 new triazole-containing sorafenib analogs. Several compounds were evaluated as potent antitumor agents. Among them, 4-(4-(4-(3-fluorophenyl-1H-1,2,3-triazol-1-ylphenoxy-N-methylpicolinamide (8f potently suppressed the proliferation of HT-29 cancer cells by inducing apoptosis and almost completely inhibited colony formation at a low micromolar concentration.

Analog earthquakes

International Nuclear Information System (INIS)

Hofmann, R.B.

1995-01-01

Analogs are used to understand complex or poorly understood phenomena for which little data may be available at the actual repository site. Earthquakes are complex phenomena, and they can have a large number of effects on the natural system, as well as on engineered structures. Instrumental data close to the source of large earthquakes are rarely obtained. The rare events for which measurements are available may be used, with modfications, as analogs for potential large earthquakes at sites where no earthquake data are available. In the following, several examples of nuclear reactor and liquified natural gas facility siting are discussed. A potential use of analog earthquakes is proposed for a high-level nuclear waste (HLW) repository

The environmental impact and risk assessment of CO2 capture, transport and storage - an evaluation of the knowledge base

NARCIS (Netherlands)

Koornneef, J.M.; Ramirez, C.A.; Turkenburg, W.C.; Faaij, A.P.C.

2012-01-01

In this study, we identify and characterize known and new environmental consequences associated with CO2 capture from power plants, transport by pipeline and storage in geological formations. We have reviewed (analogous) environmental impact assessment procedures and scientific literature on

Distribution of exogenous porphyrins in vivo; implications for neutron capture therapy

International Nuclear Information System (INIS)

Fairchild, R.G.; Gabel, D.; Hillman, M.; Watts, K.

1982-01-01

Endogenous porphyrins (HpD) are already in clinical use for phototherapy, in which red light is used to stimulate a cytotoxic response in tumors. The evident success, at least with superficial cancers, gives biological evidence of selective concentrations of porphyrins in tumors adequate for therapy. The authors have investigated, in addition, the biodistribution of a synthetic porphyrin (tetraphenylporphinesulfonate, or TPPS) in seven different animal tumor models. Their data, as well as those of others, indicate abundant accumulations of TPPS in tumor. If boronated analogs behave in the same way, boron concentrations would be up to 10 times that needed for therapy. Utilization of such porphyrin analogs in the neutron capture therapy (NCT) procedure is similar in concept to phototherapy currently being used clinically, with the distinct advantage of deeper tissue penetration produced by the activating neutrons

Cardiotonic agent milrinone stimulates resorption in rodent bone organ culture.

OpenAIRE

Krieger, N S; Stappenbeck, T S; Stern, P H

1987-01-01

The cardiotonic agent amrinone inhibits bone resorption in vitro. Milrinone, an amrinone analog, is a more potent cardiotonic agent with lower toxicity. In contrast to amrinone, milrinone stimulated resorption in cultures of neonatal mouse calvaria and fetal rat limb bones. Threshold doses were 0.1 microM in calvaria and 0.1 mM in limb bones; maximal stimulation occurred in calvaria at 0.1 mM. Maximal responses to milrinone and parathyroid hormone were comparable. Milrinone concentrations bel...

Analog circuit design

CERN Document Server

Dobkin, Bob

2012-01-01

Analog circuit and system design today is more essential than ever before. With the growth of digital systems, wireless communications, complex industrial and automotive systems, designers are being challenged to develop sophisticated analog solutions. This comprehensive source book of circuit design solutions aids engineers with elegant and practical design techniques that focus on common analog challenges. The book's in-depth application examples provide insight into circuit design and application solutions that you can apply in today's demanding designs. <

Optical analogy. Synthesis report

International Nuclear Information System (INIS)

1965-01-01

The authors report the study of conditions under which light attenuation (reflection, diffusion, absorption) and the attenuation of some radiations (notably thermal neutrons) can be described with analogical calculations. The analogy between light physical properties and neutron properties is not searched for, but the analogy between their attenuation characteristics. After having discussed this possible analogy, they propose a mathematical formulation of neutron and optical phenomena which could theoretically justify the optical analogy. The second part reports a more practical study of optics problems such as the study of simple optics materials and illumination measurements, or more precisely the study of angular distributions of optical reflections, a determination of such angular distributions, and an experimental determination of the albedo

Evaluation of video capture equipment for secondary image acquisition in the PACS.

Science.gov (United States)

Sukenobu, Yoshiharu; Sasagaki, Michihiro; Hirabuki, Norio; Naito, Hiroaki; Narumi, Yoshifumi; Inamura, Kiyonari

2002-01-01

There are many cases in which picture archiving and communication systems (PACS) are built with old-type existing modalities with no DICOM output. One of the methods for interfacing them to the PACS is to implement video capture (/ frame grabber) equipment. This equipment takes analog video signal output from medical imaging modalities, and amplitude of the video signal is A/D converted and supplied to the PACS. In this report, we measured and evaluated the accuracy at which this video capture equipment could capture the image. From the physical evaluation, we found the pixel values of an original image and its captured image were almost equal in gray level from 20%-90%. The change in the pixel values of a captured image was +/-3 on average. The change of gray level concentration was acceptable and had an average standard deviation of around 0.63. As for resolution, the degradation was observed at the highest physical level. In a subjective evaluation, the evaluation value of the CT image had a grade of 2.81 on the average (the same quality for a reference image was set to a grade of 3.0). Abnormalities in heads, chests, and abdomens were judged not to influence diagnostic accuracy. Some small differences were seen when comparing captured and reference images, but they are recognized as having no influence on the diagnoses.

Are all analogies created equal? Prefrontal cortical functioning may predict types of analogical reasoning.

Science.gov (United States)

Chrysikou, Evangelia G; Thompson-Schill, Sharon L

2010-06-01

Abstract The proposed theory can account for analogies based on learned relationships between elements in the source and target domains. However, its explanatory power regarding the discovery of new relationships during analogical reasoning is limited. We offer an alternative perspective for the role of PFC in analogical thought that may better address different types of analogical mappings.

ETUDE FONCTIONNELLE DES SYSTEMES DE CAPTURE SYNAPTOSOMALE ET VESICULAIRE DE DOPAMINE

Directory of Open Access Journals (Sweden)

M SLIMANI

2001-06-01

Full Text Available L‘injection stéréotaxique unilatérale dans la substance noire de la 6 hydroxy-dopamine ( 6OH-DA se traduit par une chute  parallèle  de  la   capture de dopamine tritiée au  niveau  synaptosomale de  l'ordre  de -70 % et dans les préparations vésiculaires de l'ordre de -69 %, comparées aux préparations issues de Rats non lésés. Ces résultats montrent que ces deux préparations synaptosomales et vésiculaires sont bien d'origine dopaminergique. D'autre part, une étude comparative de l'effet de quelques agents pharmacologiques (β carbolines, imipraminiques, amphétamine et les inhibiteurs purs de la capture synaptosomale sur la capture synaptosomale et vésiculaire de la dopamine tritiée in-vitro, montre qu'ils agissent comme de puissants inhibiteurs. Nous montrons également que le transporteur vésiculaire diffère du transporteur synaptosomal par sa stéréospécificité et sa sensibilité aux agents pharmacologiques.

Bead Capture and Release on a Magnetic Sensor in a Microfluidic System

DEFF Research Database (Denmark)

Dalslet, Bjarke Thomas; Damsgaard, Christian Danvad; Freitas, S.C.

Planar Hall effect magnetic sensors for detection of biological agents using surface treated magnetic beads are integrated with a fluid injection system. The response of the sensors is used to evaluate bead capture rates for different bead concentrations c and fluid flow rates Q, and to monitor...... subsequent removal of the beads. It is found that the capture rate scales directly with c and that it depends linearly on Q. At low Q the capture rate is only partially due to gravitational sedimentation of beads. At higher Q an additional term proportional to Q becomes important, which is attributed...... to capture of beads by the magnetic fields near the sensor. It is shown that beads can be washed off the sensor surface....

Troubleshooting analog circuits

CERN Document Server

Pease, Robert A

1991-01-01

Troubleshooting Analog Circuits is a guidebook for solving product or process related problems in analog circuits. The book also provides advice in selecting equipment, preventing problems, and general tips. The coverage of the book includes the philosophy of troubleshooting; the modes of failure of various components; and preventive measures. The text also deals with the active components of analog circuits, including diodes and rectifiers, optically coupled devices, solar cells, and batteries. The book will be of great use to both students and practitioners of electronics engineering. Other

Dynamics of bloggers’ communities: Bipartite networks from empirical data and agent-based modeling

Science.gov (United States)

Mitrović, Marija; Tadić, Bosiljka

2012-11-01

We present an analysis of the empirical data and the agent-based modeling of the emotional behavior of users on the Web portals where the user interaction is mediated by posted comments, like Blogs and Diggs. We consider the dataset of discussion-driven popular Diggs, in which all comments are screened by machine-learning emotion detection in the text, to determine positive and negative valence (attractiveness and aversiveness) of each comment. By mapping the data onto a suitable bipartite network, we perform an analysis of the network topology and the related time-series of the emotional comments. The agent-based model is then introduced to simulate the dynamics and to capture the emergence of the emotional behaviors and communities. The agents are linked to posts on a bipartite network, whose structure evolves through their actions on the posts. The emotional states (arousal and valence) of each agent fluctuate in time, subject to the current contents of the posts to which the agent is exposed. By an agent’s action on a post its current emotions are transferred to the post. The model rules and the key parameters are inferred from the considered empirical data to ensure their realistic values and mutual consistency. The model assumes that the emotional arousal over posts drives the agent’s action. The simulations are preformed for the case of constant flux of agents and the results are analyzed in full analogy with the empirical data. The main conclusions are that the emotion-driven dynamics leads to long-range temporal correlations and emergent networks with community structure, that are comparable with the ones in the empirical system of popular posts. In view of pure emotion-driven agents actions, this type of comparisons provide a quantitative measure for the role of emotions in the dynamics on real blogs. Furthermore, the model reveals the underlying mechanisms which relate the post popularity with the emotion dynamics and the prevalence of negative

Analogical Reasoning in Geometry Education

Science.gov (United States)

Magdas, Ioana

2015-01-01

The analogical reasoning isn't used only in mathematics but also in everyday life. In this article we approach the analogical reasoning in Geometry Education. The novelty of this article is a classification of geometrical analogies by reasoning type and their exemplification. Our classification includes: analogies for understanding and setting a…

Cystatin capture elisa immunodiagnosis of human fasciolosis at Chupaca-Junin Province

International Nuclear Information System (INIS)

Cornejo, W.; Alva, P.; Sevilla, C.; Huiza, A.; Universidad Nacional Mayor de San Marcos, Lima

2003-01-01

To determine the prevalence of human fasciolosis in an endemic area by means of an Enzyme-Linked Immunosorbent Assay (ELISA) using cystatin as a capture agent for the detection of specific antibodies to fasciola hepatica cysteine proteinases. An ELISA plate was sensitized with cystatin, incubated with excretory-secretory products of adult flukes, and followed by standard ELISA procedures. Clinical applicability of the cystatin capture ELISA for the immunodiagnosis of fasciolosis was tested with 200 serum samples of children and adults from an endemic area in Chupaca province, Junin department. Serum samples from the endemic area tested by cystatin capture ELISA showed 27/200 (13,5%) of positive cases. Fasciolosis remains a major health problem at Chupaca province, Junin department

Decision theory with resource-bounded agents.

Science.gov (United States)

Halpern, Joseph Y; Pass, Rafael; Seeman, Lior

2014-04-01

There have been two major lines of research aimed at capturing resource-bounded players in game theory. The first, initiated by Rubinstein (), charges an agent for doing costly computation; the second, initiated by Neyman (), does not charge for computation, but limits the computation that agents can do, typically by modeling agents as finite automata. We review recent work on applying both approaches in the context of decision theory. For the first approach, we take the objects of choice in a decision problem to be Turing machines, and charge players for the "complexity" of the Turing machine chosen (e.g., its running time). This approach can be used to explain well-known phenomena like first-impression-matters biases (i.e., people tend to put more weight on evidence they hear early on) and belief polarization (two people with different prior beliefs, hearing the same evidence, can end up with diametrically opposed conclusions) as the outcomes of quite rational decisions. For the second approach, we model people as finite automata, and provide a simple algorithm that, on a problem that captures a number of settings of interest, provably performs optimally as the number of states in the automaton increases. Copyright © 2014 Cognitive Science Society, Inc.

CO2 Capture and Reuse

International Nuclear Information System (INIS)

Thambimuthu, K.; Gupta, M.; Davison, J.

2003-01-01

CO2 capture and storage including its utilization or reuse presents an opportunity to achieve deep reductions in greenhouse gas emissions from fossil energy use. The development and deployment of this option could significantly assist in meeting a future goal of achieving stabilization of the presently rising atmospheric concentration of greenhouse gases. CO2 capture from process streams is an established concept that has achieved industrial practice. Examples of current applications include the use of primarily, solvent based capture technologies for the recovery of pure CO2 streams for chemical synthesis, for utilization as a food additive, for use as a miscible agent in enhanced oil recovery operations and removal of CO2 as an undesired contaminant from gaseous process streams for the production of fuel gases such as hydrogen and methane. In these applications, the technologies deployed for CO2 capture have focused on gas separation from high purity, high pressure streams and in reducing (or oxygen deficient) environments, where the energy penalties and cost for capture are moderately low. However, application of the same capture technologies for large scale abatement of greenhouse gas emissions from fossil fuel use poses significant challenges in achieving (at comparably low energy penalty and cost) gas separation in large volume, dilute concentration and/or low pressure flue gas streams. This paper will focus on a review of existing commercial methods of CO2 capture and the technology stretch, process integration and energy system pathways needed for their large scale deployment in fossil fueled processes. The assessment of potential capture technologies for the latter purpose will also be based on published literature data that are both 'transparent' and 'systematic' in their evaluation of the overall cost and energy penalties of CO2 capture. In view of the of the fact that many of the existing commercial processes for CO2 capture have seen applications in

Analog and mixed-signal electronics

CERN Document Server

Stephan, Karl

2015-01-01

A practical guide to analog and mixed-signal electronics, with an emphasis on design problems and applications This book provides an in-depth coverage of essential analog and mixed-signal topics such as power amplifiers, active filters, noise and dynamic range, analog-to-digital and digital-to-analog conversion techniques, phase-locked loops, and switching power supplies. Readers will learn the basics of linear systems, types of nonlinearities and their effects, op-amp circuits, the high-gain analog filter-amplifier, and signal generation. The author uses system design examples to motivate

Meat analog: a review.

Science.gov (United States)

Malav, O P; Talukder, S; Gokulakrishnan, P; Chand, S

2015-01-01

The health-conscious consumers are in search of nutritious and convenient food item which can be best suited in their busy life. The vegetarianism is the key for the search of such food which resembles the meat in respect of nutrition and sensory characters, but not of animal origin and contains vegetable or its modified form, this is the point when meat analog evolved out and gets shape. The consumers gets full satisfaction by consumption of meat analog due to its typical meaty texture, appearance and the flavor which are being imparted during the skilled production of meat analog. The supplement of protein in vegetarian diet through meat alike food can be fulfilled by incorporating protein-rich vegetative food grade materials in meat analog and by adopting proper technological process which can promote the proper fabrication of meat analog with acceptable meat like texture, appearance, flavor, etc. The easily available vegetables, cereals, and pulses in India have great advantages and prospects to be used in food products and it can improve the nutritional and functional characters of the food items. The various form and functional characters of food items are available world over and attracts the meat technologists and the food processors to bring some innovativeness in meat analog and its presentation and marketability so that the acceptability of meat analog can be overgrown by the consumers.

Digital and analog communication systems

Science.gov (United States)

Shanmugam, K. S.

1979-01-01

The book presents an introductory treatment of digital and analog communication systems with emphasis on digital systems. Attention is given to the following topics: systems and signal analysis, random signal theory, information and channel capacity, baseband data transmission, analog signal transmission, noise in analog communication systems, digital carrier modulation schemes, error control coding, and the digital transmission of analog signals.

Children's Development of Analogical Reasoning: Insights from Scene Analogy Problems

Science.gov (United States)

Richland, Lindsey E.; Morrison, Robert G.; Holyoak, Keith J.

2006-01-01

We explored how relational complexity and featural distraction, as varied in scene analogy problems, affect children's analogical reasoning performance. Results with 3- and 4-year-olds, 6- and 7-year-olds, 9- to 11-year-olds, and 13- and 14-year-olds indicate that when children can identify the critical structural relations in a scene analogy…

ESD analog circuits and design

CERN Document Server

Voldman, Steven H

2014-01-01

A comprehensive and in-depth review of analog circuit layout, schematic architecture, device, power network and ESD design This book will provide a balanced overview of analog circuit design layout, analog circuit schematic development, architecture of chips, and ESD design.  It will start at an introductory level and will bring the reader right up to the state-of-the-art. Two critical design aspects for analog and power integrated circuits are combined. The first design aspect covers analog circuit design techniques to achieve the desired circuit performance. The second and main aspect pres

Short-chain analogs of luteinizing hormone-releasing hormone containing cytotoxic moieties.

Science.gov (United States)

Janáky, T; Juhász, A; Rékási, Z; Serfözö, P; Pinski, J; Bokser, L; Srkalovic, G; Milovanovic, S; Redding, T W; Halmos, G

1992-11-01

Five hexapeptide and heptapeptide analogs of luteinizing hormone-releasing hormone (LH-RH) were synthesized for use as carriers for cytotoxic compounds. These short analogs were expected to enhance target selectivity of the antineoplastic agents linked to them. Native LH-RH-(3-9) and LH-RH-(4-9) containing D-lysine and D-ornithine at position 6 were amidated with ethylamine and acylated on the N terminus. The receptor-binding affinity of one hexapeptide carrier AJ-41 (Ac-Ser-Tyr-D-Lys-Leu-Arg-Pro-NH-Et) to human breast cancer cell membranes was similar to that of [D-Trp6]LH-RH. Alkylating nitrogen mustards (melphalan, Ac-melphalan), anthraquinone derivatives including anticancer antibiotic doxorubicin, antimetabolite (methotrexate), and cisplatin-like platinum complex were linked to these peptides through their omega-amino group at position 6. The hybrid molecules showed no LH-RH agonistic activity in vitro and in vivo but had nontypical antagonistic effects on pituitary cells in vitro at the doses tested. These analogs showed a wide range of receptor-binding affinities to rat pituitaries and cell membranes of human breast cancer and rat Dunning prostate cancer. Several of these conjugates exerted some cytotoxic effects on MCF-7 breast cancer cell line.

Hydraulic Capacitor Analogy

Science.gov (United States)

Baser, Mustafa

2007-01-01

Students have difficulties in physics because of the abstract nature of concepts and principles. One of the effective methods for overcoming students' difficulties is the use of analogies to visualize abstract concepts to promote conceptual understanding. According to Iding, analogies are consistent with the tenets of constructivist learning…

Analog fourier transform channelizer and OFDM receiver

OpenAIRE

2007-01-01

An OFDM receiver having an analog multiplier based I-Q channelizing filter, samples and holds consecutive analog I-Q samples of an I-Q baseband, the I-Q basebands having OFDM sub-channels. A lattice of analog I-Q multipliers and analog I-Q summers concurrently receives the held analog I-Q samples, performs analog I-Q multiplications and analog I-Q additions to concurrently generate a plurality of analog I-Q output signals, representing an N-point discrete Fourier transform of the held analog ...

Vitamin E analogs, a novel group of "mitocans," as anticancer agents: The importance of being redox-silent

Czech Academy of Sciences Publication Activity Database

Neužil, Jiří; Tomasetti, M.; Zhao, Y.; Dong, L.F.; Birringer, M.; Wang, X. F.; Low, P.; Wu, K.; Salvatore, B.A.; Ralph, S.J.

2007-01-01

Roč. 71, č. 5 (2007), s. 1185-1199 ISSN 0026-895X Institutional research plan: CEZ:AV0Z50520514; CEZ:AV0Z50520701 Keywords : vitamin E analogs * redox- silence * anticancer drugs Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.622, year: 2007

The use of anthracycline at first-line compared to alkylating agents or nucleoside analogs improves the outcome of salvage treatments after relapse in follicular lymphoma The REFOLL study by the Fondazione Italiana Linfomi.

Science.gov (United States)

Rossi, Giuseppe; Marcheselli, Luigi; Dondi, Alessandra; Bottelli, Chiara; Tucci, Alessandra; Luminari, Stefano; Arcaini, Luca; Merli, Michele; Pulsoni, Alessandro; Boccomini, Carola; Puccini, Benedetta; Micheletti, Moira; Martinelli, Giovanni; Rossi, Andrea; Zilioli, Vittorio Ruggero; Bozzoli, Valentina; Balzarotti, Monica; Bolis, Silvia; Cabras, Maria Giuseppina; Federico, Massimo

2015-01-01

Follicular lymphoma (FL) patients experience multiple remissions and relapses and commonly receive multiple treatment lines. A crucial question is whether anthracyclines should be used at first-line or whether they would be better "reserved" for relapse and whether FL outcome can be optimized by definite sequences of treatments. Randomized trials can be hardly designed to address this question. In this retrospective multi-institutional study, time-to-next-treatment after first relapse was analyzed in 510 patients who had received either alkylating agents- or anthracycline- or nucleoside analogs-based chemotherapy with/without rituximab at first-line and different second-line therapies. After a median of 42 months, median time-to-next-treatment after relapse was 41 months (CI95%:34-47 months). After adjustment for covariates, first-line anthracycline-based chemotherapy with/without rituximab was associated with better time-to-next-treatment after any salvage than alkylating agents-based chemotherapy with/without rituximab or nucleoside analogs-based chemotherapy with/without rituximab (HR:0.74, P = 0.027). The addition of rituximab to first-line chemotherapy had no significant impact (HR:1.22, P = 0.140). Autologs stem cell transplantation performed better than any other salvage treatment (HR:0.53, P < 0.001). First-line anthracycline-based chemotherapy significantly improved time-to-next-treatment even in patients receiving salvage autologs stem cell transplantation (P = 0.041). This study supports the concept that in FL previous treatments significantly impact on the outcome of subsequent therapies. The outcome of second-line treatments, either with salvage chemoimmunotherapy or with autologs stem cell transplantation, was better when an anthracycline-containing regimen was used at first-line. © 2014 Wiley Periodicals, Inc.

Synthesis and optimization of novel allylated mono-carbonyl analogs of curcumin (MACs) act as potent anti-inflammatory agents against LPS-induced acute lung injury (ALI) in rats.

Science.gov (United States)

Zhu, Heping; Xu, Tingting; Qiu, Chenyu; Wu, Beibei; Zhang, Yali; Chen, Lingfeng; Xia, Qinqin; Li, Chenglong; Zhou, Bin; Liu, Zhiguo; Liang, Guang

2016-10-04

A series of novel symmetric and asymmetric allylated mono-carbonyl analogs of curcumin (MACs) were synthesized using an appropriate synthetic route and evaluated experimentally thru the LPS-induced expression of TNF-α and IL-6. Most of the obtained compounds exhibited improved water solubility as a hydrochloride salt compared to lead molecule 8f. The most active compound 7a was effective in reducing the Wet/Dry ratio in the lungs and protein concentration in bronchoalveolar lavage fluid. Meanwhile, 7a also inhibited mRNA expression of several inflammatory cytokines, including TNF-α, IL-6, IL-1β, and VCAM-1, in Beas-2B cells after Lipopolysaccharide (LPS) challenge. These results suggest that 7a could be therapeutically beneficial for use as an anti-inflammatory agent in the clinical treatment of acute lung injury (ALI). Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Inductive, Analogical, and Communicative Generalization

Directory of Open Access Journals (Sweden)

Adri Smaling

2003-03-01

Full Text Available Three forms of inductive generalization - statistical generalization, variation-based generalization and theory-carried generalization - are insufficient concerning case-to-case generalization, which is a form of analogical generalization. The quality of case-to-case generalization needs to be reinforced by setting up explicit analogical argumentation. To evaluate analogical argumentation six criteria are discussed. Good analogical reasoning is an indispensable support to forms of communicative generalization - receptive and responsive (participative generalization — as well as exemplary generalization.

Analog insulin detemir for patients with type 1 and type 2 diabetes: a review

Directory of Open Access Journals (Sweden)

Gregory E Peterson

2009-05-01

Full Text Available Gregory E PetersonDepartment of Internal Medicine, Des Moines University, USAObjective: To review insulin detemir for clinical use to better manage patients with type 1 and type 2 diabetes.Methods: A MEDLINE search, in English, from June 30, 2006 to December 1, 2008, using the terms “insulin analogs,” “insulin detemir” and “long-acting insulin analog.”Results: Insulin detemir improves glycemic control, based on HbA1C reduction and fasting glucose levels, without increasing the risk of hypoglycemia and weight gain. Insulin detemir has lower glycemic variability, with less intra-subject variability in blood glucose levels in patients with type 1 and type 2 diabetes, without increasing the risk of hypoglycemia. When added to oral anti-diabetes agents (OADs in type 2 diabetes, insulin detemir demonstrates superiority to other basal insulin options.Conclusion: Insulin detemir appears to provide better glycemic control with a lower risk of hypoglycemia and less weight gain in the treatment of patients with type 1 and type 2 diabetes.Keywords: type 1 diabetes, type 2 diabetes, insulin analogs, insulin detemir

Natural analogs of the long-term performance of engineered covers

International Nuclear Information System (INIS)

Waugh, W.J.; Petersen, K.L.; Link, S.O.; Bjornstad, B.N.; Gee, G.W.

1994-01-01

The unprecedented legislative demand that in-situ waste-disposal facilities effectively persist indefinitely requires a performance assessment approach that exceeds standard engineering practices and incorporates possible long-term changes in site hydrology, geology, and ecology. Even in relatively arid regions, over time, buried waste will be vulnerable to transport via rainwater percolation, gas diffusion, erosion, and intrusion by plant roots, burrowing animals, and humans. Standard models and field tests of engineered covers designed to impede these pathways implicitly and erroneously assume that initial conditions of many key determinants will persist indefinitely. Evidence from natural, archaeological, and engineered analogs is needed (1) to identify and understand emergent system attributes that cannot be captured with computer models or short-term experiments, and (2) to develop modeling and field tests that reasonably bound possible future changes in waste-site environments. Analogs of local responses to future global climate change exist as proxy ecological and archaeological records of similar paleoclimates. Future pedogenic influences can be inferred form measurements of key soil properties in natural and archaeological soil profiles analogous to engineered covers. Many cover designs depend on water extraction by plants. Influences of vegetation change can be inferred by measuring water extraction parameters in plant communities representing successional chronosequences. Habitats similar to those created on waste sites provide evidence of the potential for biological intrusion. Recent and ancient man-made structures provide evidence of the future stability of waste-site covers and of features that may discourage human intrusion. 108 refs., 4 figs

Sensing and capture of toxic and hazardous gases and vapors by metal-organic frameworks.

Science.gov (United States)

Wang, Hao; Lustig, William P; Li, Jing

2018-03-13

Toxic and hazardous chemical species are ubiquitous, predominantly emitted by anthropogenic activities, and pose serious risks to human health and the environment. Thus, the sensing and subsequent capture of these chemicals, especially in the gas or vapor phase, are of extreme importance. To this end, metal-organic frameworks have attracted significant interest, as their high porosity and wide tunability make them ideal for both applications. These tailorable framework materials are particularly promising for the specific sensing and capture of targeted chemicals, as they can be designed to fit a diverse range of required conditions. This review will discuss the advantages of metal-organic frameworks in the sensing and capture of harmful gases and vapors, as well as principles and strategies guiding the design of these materials. Recent progress in the luminescent detection of aromatic and aliphatic volatile organic compounds, toxic gases, and chemical warfare agents will be summarized, and the adsorptive removal of fluorocarbons/chlorofluorocarbons, volatile radioactive species, toxic industrial gases and chemical warfare agents will be discussed.

Metal-organic frameworks for the removal of toxic industrial chemicals and chemical warfare agents.

Science.gov (United States)

Bobbitt, N Scott; Mendonca, Matthew L; Howarth, Ashlee J; Islamoglu, Timur; Hupp, Joseph T; Farha, Omar K; Snurr, Randall Q

2017-06-06

Owing to the vast diversity of linkers, nodes, and topologies, metal-organic frameworks can be tailored for specific tasks, such as chemical separations or catalysis. Accordingly, these materials have attracted significant interest for capture and/or detoxification of toxic industrial chemicals and chemical warfare agents. In this paper, we review recent experimental and computational work pertaining to the capture of several industrially-relevant toxic chemicals, including NH 3 , SO 2 , NO 2 , H 2 S, and some volatile organic compounds, with particular emphasis on the challenging issue of designing materials that selectively adsorb these chemicals in the presence of water. We also examine recent research on the capture and catalytic degradation of chemical warfare agents such as sarin and sulfur mustard using metal-organic frameworks.

Developing Inhibitors of Translesion DNA Synthesis as Therapeutic Agents Against Lung Cancer

Science.gov (United States)

2014-10-01

pol eta when replicating damaged DNA. 1S. SUBJECT TERMS: Mutagenesis, DNA polymerases, nucleoside analogs, chemotherapeutic agents 16. SECURITY ...such as polymerase eta, iota , and kappa that are involved in replicating damaged DNA. Our kinetic data obtained under Task 1B indicates that pol eta

9 CFR 113.55 - Detection of extraneous agents in Master Seed Virus.

Science.gov (United States)

2010-01-01

... Master Seed Virus. 113.55 Section 113.55 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS; ORGANISMS AND VECTORS STANDARD REQUIREMENTS Ingredient Requirements § 113.55 Detection of extraneous agents in Master Seed Virus...

Analogical Reasoning and Computer Programming.

Science.gov (United States)

Clement, Catherine A.; And Others

1986-01-01

A study of correlations between analogical reasoning and Logo programming mastery among female high school students related the results of pretests of analogical reasoning to posttests of programming mastery. A significant correlation was found between analogical reasoning and the ability to write subprocedures for use in several different…

Magnetizable stent-grafts enable endothelial cell capture

Energy Technology Data Exchange (ETDEWEB)

Tefft, Brandon J. [Department of Cardiovascular Diseases, Mayo Clinic, Rochester, MN (United States); Uthamaraj, Susheil [Division of Engineering, Mayo Clinic, Rochester, MN (United States); Harburn, J. Jonathan [School of Medicine, Pharmacy and Health, Durham University, Stockton-on-Tees (United Kingdom); Hlinomaz, Ota [Department of Cardioangiology, St. Anne' s University Hospital, Brno (Czech Republic); Lerman, Amir [Department of Cardiovascular Diseases, Mayo Clinic, Rochester, MN (United States); Dragomir-Daescu, Dan [Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, MN (United States); Sandhu, Gurpreet S., E-mail: sandhu.gurpreet@mayo.edu [Department of Cardiovascular Diseases, Mayo Clinic, Rochester, MN (United States)

2017-04-01

Emerging nanotechnologies have enabled the use of magnetic forces to guide the movement of magnetically-labeled cells, drugs, and other therapeutic agents. Endothelial cells labeled with superparamagnetic iron oxide nanoparticles (SPION) have previously been captured on the surface of magnetizable 2205 duplex stainless steel stents in a porcine coronary implantation model. Recently, we have coated these stents with electrospun polyurethane nanofibers to fabricate prototype stent-grafts. Facilitated endothelialization may help improve the healing of arteries treated with stent-grafts, reduce the risk of thrombosis and restenosis, and enable small-caliber applications. When placed in a SPION-labeled endothelial cell suspension in the presence of an external magnetic field, magnetized stent-grafts successfully captured cells to the surface regions adjacent to the stent struts. Implantation within the coronary circulation of pigs (n=13) followed immediately by SPION-labeled autologous endothelial cell delivery resulted in widely patent devices with a thin, uniform neointima and no signs of thrombosis or inflammation at 7 days. Furthermore, the magnetized stent-grafts successfully captured and retained SPION-labeled endothelial cells to select regions adjacent to stent struts and between stent struts, whereas the non-magnetized control stent-grafts did not. Early results with these prototype devices are encouraging and further refinements will be necessary in order to achieve more uniform cell capture and complete endothelialization. Once optimized, this approach may lead to more rapid and complete healing of vascular stent-grafts with a concomitant improvement in long-term device performance. - Highlights: • Magnetic stent-grafts were made from 2205 steel stents and polyurethane nanofibers. • Stent-grafts remained patent and formed a thin and uniform neointima when implanted. • Stent-grafts captured endothelial cells labeled with magnetic nanoparticles. �

Automating analog design: Taming the shrew

Science.gov (United States)

Barlow, A.

1990-01-01

The pace of progress in the design of integrated circuits continues to amaze observers inside and outside of the industry. Three decades ago, a 50 transistor chip was a technological wonder. Fifteen year later, a 5000 transistor device would 'wow' the crowds. Today, 50,000 transistor chips will earn a 'not too bad' assessment, but it takes 500,000 to really leave an impression. In 1975 a typical ASIC device had 1000 transistors, took one year to first samples (and two years to production) and sold for about 5 cents per transistor. Today's 50,000 transistor gate array takes about 4 months from spec to silicon, works the first time, and sells for about 0.02 cents per transistor. Fifteen years ago, the single most laborious and error prone step in IC design was the physical layout. Today, most IC's never see the hand of a layout designer: and automatic place and route tool converts the engineer's computer captured schematic to a complete physical design using a gate array or a library of standard cells also created by software rather than by designers. CAD has also been a generous benefactor to the digital design process. The architect of today's digital systems creates the design using an RTL or other high level simulator. Then the designer pushes a button to invoke the logic synthesizer-optimizer tool. A fault analyzer checks the result for testability and suggests where scan based cells will improve test coverage. One obstinate holdout amidst this parade of progress is the automation of analog design and its reduction to semi-custom techniques. This paper investigates the application of CAD techniques to analog design.

Analogical reasoning in children with specific language impairment: Evidence from a scene analogy task.

Science.gov (United States)

Krzemien, Magali; Jemel, Boutheina; Maillart, Christelle

2017-01-01

Analogical reasoning is a human ability that maps systems of relations. It develops along with relational knowledge, working memory and executive functions such as inhibition. It also maintains a mutual influence on language development. Some authors have taken a greater interest in the analogical reasoning ability of children with language disorders, specifically those with specific language impairment (SLI). These children apparently have weaker analogical reasoning abilities than their aged-matched peers without language disorders. Following cognitive theories of language acquisition, this deficit could be one of the causes of language disorders in SLI, especially those concerning productivity. To confirm this deficit and its link to language disorders, we use a scene analogy task to evaluate the analogical performance of SLI children and compare them to controls of the same age and linguistic abilities. Results show that children with SLI perform worse than age-matched peers, but similar to language-matched peers. They are more influenced by increased task difficulty. The association between language disorders and analogical reasoning in SLI can be confirmed. The hypothesis of limited processing capacity in SLI is also being considered.

Synthesis of a Fluorescently Labeled 68Ga-DOTA-TOC Analog for Somatostatin Receptor Targeting.

Science.gov (United States)

Ghosh, Sukhen C; Hernandez Vargas, Servando; Rodriguez, Melissa; Kossatz, Susanne; Voss, Julie; Carmon, Kendra S; Reiner, Thomas; Schonbrunn, Agnes; Azhdarinia, Ali

2017-07-13

Fluorescently labeled imaging agents can identify surgical margins in real-time to help achieve complete resections and minimize the likelihood of local recurrence. However, photon attenuation limits fluorescence-based imaging to superficial lesions or lesions that are a few millimeters beneath the tissue surface. Contrast agents that are dual-labeled with a radionuclide and fluorescent dye can overcome this limitation and combine quantitative, whole-body nuclear imaging with intraoperative fluorescence imaging. Using a multimodality chelation (MMC) scaffold, IRDye 800CW was conjugated to the clinically used somatostatin analog, 68 Ga-DOTA-TOC, to produce the dual-labeled analog, 68 Ga-MMC(IRDye 800CW)-TOC, with high yield and specific activity. In vitro pharmacological assays demonstrated retention of receptor-targeting properties for the dual-labeled compound with robust internalization that was somatostatin receptor (SSTR) 2-mediated. Biodistribution studies in mice identified the kidneys as the primary excretion route for 68 Ga-MMC(IRDye 800CW)-TOC, along with clearance via the reticuloendothelial system. Higher uptake was observed in most tissues compared to 68 Ga-DOTA-TOC but decreased as a function of time. The combination of excellent specificity for SSTR2-expressing cells and suitable biodistribution indicate potential application of 68 Ga-MMC(IRDye 800CW)-TOC for intraoperative detection of SSTR2-expressing tumors.

Intensive fibrosarcoma-binding capability of the reconstituted analog and its antitumor activity.

Science.gov (United States)

Xu, Jian; Du, Yue; Liu, Wen-Juan; Li, Liang; Li, Yi; Wang, Xiao-Fei; Yi, Hong-Fei; Shan, Chuan-Kun; Xia, Gui-Min; Liu, Xiu-Jun; Zhen, Yong-Su

2018-11-01

Fibrosarcomas are highly aggressive malignant tumors. It is urgently needed to explore targeted drugs and modalities for more effective therapy. Matrix metalloproteinases (MMPs) play important roles in tumor progression and metastasis, while several MMPs are highly expressed in fibrosarcomas. In addition, tissue inhibitor of metalloproteinase 2 (TIMP2) displays specific interaction with MMPs. Therefore, TIMP2 may play an active role in the development of fibrosarcoma-targeting agents. In the current study, a TIMP2-based recombinant protein LT and its enediyne-integrated analog LTE were prepared; furthermore, the fibrosarcoma-binding intensity and antitumor activity were investigated. As shown, intense and selective binding capability of the protein LT to human fibrosarcoma specimens was confirmed by tissue microarray. Moreover, LTE, the enediyne-integrated analog of LT, exerted highly potent cytotoxicity to fibrosarcoma HT1080 cells, induced apoptosis, and caused G2/M arrest. LTE at 0.1 nM markedly suppressed the migration and invasion of HT1080 cells. LTE at tolerated dose of 0.6 mg/kg inhibited the tumor growth of fibrosarcoma xenograft in athymic mice. The study provides evidence that the TIMP2-based reconstituted analog LTE may be useful as a targeted drug for fibrosarcome therapy.

PEMETAAN ANALOGI PADA KONSEP ABSTRAK FISIKA

Directory of Open Access Journals (Sweden)

Nyoto Suseno

2014-11-01

Full Text Available The research of any where founded majority students have common difficulties in abstract physics concept. The result of observation, lecturers have problem  in teaching implementation of abstract concepts on physics learning. The objective of this research is to find out the ways how to overcome this problem. The research place of  physics education programs and senior high school. The data are colected by quetionere, observation and interview. The lecturer behavior to making out this case is use of analogy to make concrete a abstract concept. This action is true, because the analogies are dynamic tools that facilitate understanding, rather than representations of the correct and static explanations. Using analogies not only promoted profound understanding of abstract concept, but also helped students overcome their misconceptions. However used analogy in teaching not yet planed with seriousness, analogy used spontanously with the result that less optimal. By planing and selecting right analogy, the role of analogy can be achieved the optimal result. Therefore, it is important to maping analogies of abstract consepts on physics learning.

Science Teachers' Analogical Reasoning

Science.gov (United States)

Mozzer, Nilmara Braga; Justi, Rosária

2013-01-01

Analogies can play a relevant role in students' learning. However, for the effective use of analogies, teachers should not only have a well-prepared repertoire of validated analogies, which could serve as bridges between the students' prior knowledge and the scientific knowledge they desire them to understand, but also know how to…

Analog circuits cookbook

CERN Document Server

Hickman, Ian

2013-01-01

Analog Circuits Cookbook presents articles about advanced circuit techniques, components and concepts, useful IC for analog signal processing in the audio range, direct digital synthesis, and ingenious video op-amp. The book also includes articles about amplitude measurements on RF signals, linear optical imager, power supplies and devices, and RF circuits and techniques. Professionals and students of electrical engineering will find the book informative and useful.

Dendrimer-based Macromolecular MRI Contrast Agents: Characteristics and Application

Directory of Open Access Journals (Sweden)

Hisataka Kobayashi

2003-01-01

Full Text Available Numerous macromolecular MRI contrast agents prepared employing relatively simple chemistry may be readily available that can provide sufficient enhancement for multiple applications. These agents operate using a ~100-fold lower concentration of gadolinium ions in comparison to the necessary concentration of iodine employed in CT imaging. Herein, we describe some of the general potential directions of macromolecular MRI contrast agents using our recently reported families of dendrimer-based agents as examples. Changes in molecular size altered the route of excretion. Smaller-sized contrast agents less than 60 kDa molecular weight were excreted through the kidney resulting in these agents being potentially suitable as functional renal contrast agents. Hydrophilic and larger-sized contrast agents were found better suited for use as blood pool contrast agents. Hydrophobic variants formed with polypropylenimine diaminobutane dendrimer cores created liver contrast agents. Larger hydrophilic agents are useful for lymphatic imaging. Finally, contrast agents conjugated with either monoclonal antibodies or with avidin are able to function as tumor-specific contrast agents, which also might be employed as therapeutic drugs for either gadolinium neutron capture therapy or in conjunction with radioimmunotherapy.

Dynamic Synchronous Capture Algorithm for an Electromagnetic Flowmeter.

Science.gov (United States)

Fanjiang, Yong-Yi; Lu, Shih-Wei

2017-04-10

This paper proposes a dynamic synchronous capture (DSC) algorithm to calculate the flow rate for an electromagnetic flowmeter. The characteristics of the DSC algorithm can accurately calculate the flow rate signal and efficiently convert an analog signal to upgrade the execution performance of a microcontroller unit (MCU). Furthermore, it can reduce interference from abnormal noise. It is extremely steady and independent of fluctuations in the flow measurement. Moreover, it can calculate the current flow rate signal immediately (m/s). The DSC algorithm can be applied to the current general MCU firmware platform without using DSP (Digital Signal Processing) or a high-speed and high-end MCU platform, and signal amplification by hardware reduces the demand for ADC accuracy, which reduces the cost.

Inorganic membranes for carbon capture and power generation

Science.gov (United States)

Snider, Matthew T.

Inorganic membranes are under consideration for cost-effective reductions of carbon emissions from coal-fired power plants, both in the capture of pollutants post-firing and in the direct electrochemical conversion of coal-derived fuels for improved plant efficiency. The suitability of inorganic membrane materials for these purposes stems as much from thermal and chemical stability in coal plant operating conditions as from high performance in gas separations and power generation. Hydrophilic, micro-porous zeolite membrane structures are attractive for separating CO2 from N2 in gaseous waste streams due to the attraction of CO2 to the membrane surface and micropore walls that gives the advantage to CO2 transport. Recent studies have indicated that retention of the templating agent used in zeolite synthesis can further block N2 from the micropore interior and significantly improve CO2/N2 selectivity. However, the role of the templating agent in micro-porous transport has not been well investigated. In this work, gas sorption studies were conducted by high-pressure thermo-gravimetric analysis on Zeolite Y membrane materials to quantify the effect of the templating agent on CO2, N2, and H2O adsorption/desorption, as well as to examine the effect of humidification on overall membrane performance. In equilibrium conditions, the N2 sorption enthalpy was nearly unchanged by the presence of the templating agent, but the N2 pore occupation was reduced ˜1000x. Thus, the steric nature of the blocking of N2 from the micropores by the templating agent was confirmed. CO2 and H2O sorption enthalpies were similarly unaffected by the templating agent, and the micropore occupations were only reduced as much as the void volume taken up by the templating agent. Thus, the steric blocking effect did not occur for molecules more strongly attracted to the micropore walls. Additionally, in time-transient measurements the CO 2 and H2O mobilities were significantly enhanced by the presence

Tangential channel for nuclear gamma-resonance spectroscopy in thermal neutron capture

International Nuclear Information System (INIS)

Belogurov, V.N.; Bondars, H.Ya.; Lapenas, A.A.; Reznikov, R.S.; Senkov, P.E.

1979-01-01

Design of a tangential reactor channel which has been made to replace the radial one in the pulsed research reactor IRT-2000 is described. It allows to use the same hole in biological reactor schielding. Characteristics of neutron and gamma-background spectra at the excit of the channel are given and compared with analogous characteristics of the radial one. The gamma background in the tangential channel is lower than in the radial channel. The gamma spectra in the Gd 155 (n, γ)Gd 156 , Gd 157 (n, γ)Gd 158 , Er 167 (n, γ)Er 168 and Hf 177 (n, γ)Hf 178 reactions show that the application of X-ray detection units BDR with the tangential channel allows to carry out the gamma spectrometry of gamma quanta emitted in the thermal neutron capture by both high and low neutron capture cross section nuclei (e.g., Gdsup(157, 155) and Er 167 , Hf 177 , respectively)

Advances in Analog Circuit Design 2015

CERN Document Server

Baschirotto, Andrea; Harpe, Pieter

2016-01-01

This book is based on the 18 tutorials presented during the 24th workshop on Advances in Analog Circuit Design. Expert designers present readers with information about a variety of topics at the frontier of analog circuit design, including low-power and energy-efficient analog electronics, with specific contributions focusing on the design of efficient sensor interfaces and low-power RF systems. This book serves as a valuable reference to the state-of-the-art, for anyone involved in analog circuit research and development. ·         Provides a state-of-the-art reference in analog circuit design, written by experts from industry and academia; ·         Presents material in a tutorial-based format; ·         Includes coverage of high-performance analog-to-digital and digital to analog converters, integrated circuit design in scaled technologies, and time-domain signal processing.

Magnetizable stent-grafts enable endothelial cell capture

Science.gov (United States)

Tefft, Brandon J.; Uthamaraj, Susheil; Harburn, J. Jonathan; Hlinomaz, Ota; Lerman, Amir; Dragomir-Daescu, Dan; Sandhu, Gurpreet S.

2017-04-01

Emerging nanotechnologies have enabled the use of magnetic forces to guide the movement of magnetically-labeled cells, drugs, and other therapeutic agents. Endothelial cells labeled with superparamagnetic iron oxide nanoparticles (SPION) have previously been captured on the surface of magnetizable 2205 duplex stainless steel stents in a porcine coronary implantation model. Recently, we have coated these stents with electrospun polyurethane nanofibers to fabricate prototype stent-grafts. Facilitated endothelialization may help improve the healing of arteries treated with stent-grafts, reduce the risk of thrombosis and restenosis, and enable small-caliber applications. When placed in a SPION-labeled endothelial cell suspension in the presence of an external magnetic field, magnetized stent-grafts successfully captured cells to the surface regions adjacent to the stent struts. Implantation within the coronary circulation of pigs (n=13) followed immediately by SPION-labeled autologous endothelial cell delivery resulted in widely patent devices with a thin, uniform neointima and no signs of thrombosis or inflammation at 7 days. Furthermore, the magnetized stent-grafts successfully captured and retained SPION-labeled endothelial cells to select regions adjacent to stent struts and between stent struts, whereas the non-magnetized control stent-grafts did not. Early results with these prototype devices are encouraging and further refinements will be necessary in order to achieve more uniform cell capture and complete endothelialization. Once optimized, this approach may lead to more rapid and complete healing of vascular stent-grafts with a concomitant improvement in long-term device performance.

Building an Educational Program together health community agents

Directory of Open Access Journals (Sweden)

Lúcia Rondelo Duarte

2007-01-01

Full Text Available Aiming at contributing inputs to the learning process of community health agents from Family Health Strategy, this study has sought to devise an Educational Program to qualify seven community agents from the Family Health Unit on Habiteto, a neighborhood in the Brazilian city of Sorocaba. Speeches on the perception these agents have of their work, their difficulties and proposals were captured and analyzed within the framework of the "Collective Subject Speech". Results showed the group's learning needs, and guided the devising and implementation of the Educational Program, which adopted the "Problem-Based Education" model. This knowledge was built by the agents through a problem-focused reality, debating, searching for solutions, and implementing intervention projects. They noticed that being a community health agent means, above all, to struggle and harness community forces for purposes of defending health & education public services and for improving social health determinants.

Analysis of epoxyeicosatrienoic acids by chiral liquid chromatography/electron capture atmospheric pressure chemical ionization mass spectrometry using [13C]-analog internal standards

Science.gov (United States)

Mesaros, Clementina; Lee, Seon Hwa; Blair, Ian A.

2012-01-01

The metabolism of arachidonic acid (AA) to epoxyeicosatrienoic acids (EETs) is thought to be mediated primarily by the cytochromes P450 (P450s) from the 2 family (2C9, 2C19, 2D6, and 2J2). In contrast, P450s of the 4 family are primarily involved in omega oxidation of AA (4A11 and 4A22). The ability to determine enantioselective formation of the regioisomeric EETs is important in order to establish their potential biological activities and to asses which P450 isoforms are involved in their formation. It has been extremely difficult to analyze individual EET enantiomers in biological fluids because they are present in only trace amounts and they are extremely difficult to separate from each other. In addition, the deuterium-labeled internal standards that are commonly used for stable isotope dilution liquid chromatography/mass spectrometry (LC/MS) analyses have different LC retention times when compared with the corresponding protium forms. Therefore, quantification by LC/MS-based methodology can be compromised by differential suppression of ionization of the closely eluting isomers. We report the preparation of [13C20]-EET analog internal standards and the use of a validated high-sensitivity chiral LC/electron capture atmospheric pressure chemical ionization (ECAPCI)-MS method for the trace analysis of endogenous EETs as their pentafluorobenzyl (PFB) ester derivatives. The assay was then used to show the exquisite enantioselectivity of P4502C19-, P4502D6-, P4501A1-, and P4501B1-mediated conversion of AA into EETs and to quantify the enantioselective formation of EETs produced by AA metabolism in a mouse epithelial hepatoma (Hepa) cell line. PMID:20972997

Learning in engineered multi-agent systems

Science.gov (United States)

Menon, Anup

Consider the problem of maximizing the total power produced by a wind farm. Due to aerodynamic interactions between wind turbines, each turbine maximizing its individual power---as is the case in present-day wind farms---does not lead to optimal farm-level power capture. Further, there are no good models to capture the said aerodynamic interactions, rendering model based optimization techniques ineffective. Thus, model-free distributed algorithms are needed that help turbines adapt their power production on-line so as to maximize farm-level power capture. Motivated by such problems, the main focus of this dissertation is a distributed model-free optimization problem in the context of multi-agent systems. The set-up comprises of a fixed number of agents, each of which can pick an action and observe the value of its individual utility function. An individual's utility function may depend on the collective action taken by all agents. The exact functional form (or model) of the agent utility functions, however, are unknown; an agent can only measure the numeric value of its utility. The objective of the multi-agent system is to optimize the welfare function (i.e. sum of the individual utility functions). Such a collaborative task requires communications between agents and we allow for the possibility of such inter-agent communications. We also pay attention to the role played by the pattern of such information exchange on certain aspects of performance. We develop two algorithms to solve this problem. The first one, engineered Interactive Trial and Error Learning (eITEL) algorithm, is based on a line of work in the Learning in Games literature and applies when agent actions are drawn from finite sets. While in a model-free setting, we introduce a novel qualitative graph-theoretic framework to encode known directed interactions of the form "which agents' action affect which others' payoff" (interaction graph). We encode explicit inter-agent communications in a directed

Capture of negative muons in magnesium oxides and crystalline modifications of phosphorus

International Nuclear Information System (INIS)

Zinov, V.G.; Kachalkin, A.K.; Nikityuk, L.N.; Pokrovskij, V.N.; Rybakov, V.N.; Yutlandov, I.A.

1977-01-01

The paper is aimed at comparing the structure of mesic K X-ray patterns of phosphorus in its crystalline modifications, comparing the structure of mesic X-ray patterns of magnesium and oxygen in compounds of MgO, MgO 2 , H 2 O and metallic magnesium, as well as comparison of propabilities of μ - atomic capture in magnesium oxides. By analyzing the mesic K X-ray patterns of red and white phosphorus it is concluded that the phosphorus crystalline modification produces the effect on the line structure, the higher series number being somewhat larger for the allotrope of phosphorus with polymeric structure. A comparison is made of the mesic X-ray series of the magnesium in oxide and metal, of the oxygen in oxide and water with the analogous data for aluminium and silicon. The data confirm the supposition that chemical bond (valence electrons) plays a substantial role in meson capture

Students' Pre- and Post-Teaching Analogical Reasoning when They Draw Their Analogies

Science.gov (United States)

Mozzer, Nilmara Braga; Justi, Rosaria

2012-01-01

Analogies are parts of human thought. From them, we can acquire new knowledge or change that which already exists in our cognitive structure. In this sense, understanding the analogical reasoning process becomes an essential condition to understand how we learn. Despite the importance of such an understanding, there is no general agreement in…

Analogical proportions: another logical view

Science.gov (United States)

Prade, Henri; Richard, Gilles

This paper investigates the logical formalization of a restricted form of analogical reasoning based on analogical proportions, i.e. statements of the form a is to b as c is to d. Starting from a naive set theoretic interpretation, we highlight the existence of two noticeable companion proportions: one states that a is to b the converse of what c is to d (reverse analogy), while the other called paralogical proportion expresses that what a and b have in common, c and d have it also. We identify the characteristic postulates of the three types of proportions and examine their consequences from an abstract viewpoint. We further study the properties of the set theoretic interpretation and of the Boolean logic interpretation, and we provide another light on the understanding of the role of permutations in the modeling of the three types of proportions. Finally, we address the use of these proportions as a basis for inference in a propositional setting, and relate it to more general schemes of analogical reasoning. The differences between analogy, reverse-analogy, and paralogy is still emphasized in a three-valued setting, which is also briefly presented.

Interactive Embodied Agents for Cultural Heritage and Archaeological presentations

Directory of Open Access Journals (Sweden)

F. Seron

2010-04-01

Full Text Available In this paper, Maxine, a powerful engine to develop applications with embodied animated agents is presented. The engine, based on the use of open source libraries, enables multimodal real-time interaction with the user: via text, voice, images and gestures. Maxine virtual agents can establish emotional communication with the user through their facial expressions, the modulation of the voice and expressing the answers of the agents according to the information gathered by the system: noise level in the room, observer’s position, emotional state of the observer, etc. Moreover, the user’s emotions are considered and captured through images. For the moment, Maxine virtual agents have been used as virtual presenters for Cultural Heritage and Archaeological shows.

Ultrasound-induced Gas Release from Contrast Agent Microbubbles

NARCIS (Netherlands)

Postema, M.A.B.; Postema, Michiel; Bouakaz, Ayache; Versluis, Michel; de Jong, N.

2005-01-01

We investigated gas release from two hard-shelled ultrasound contrast agents by subjecting them to high-mechanical index (MI) ultrasound and simultaneously capturing high-speed photographs. At an insonifying frequency of 1.7 MHz, a larger percentage of contrast bubbles is seen to crack than at 0.5

The need for and development of behaviourally realistic agents

NARCIS (Netherlands)

Jager, W; Janssen, M; Sichman, JS; Bousquet, F; Davidsson, P

2003-01-01

In this paper we argue that simulating complex systems involving human behaviour requires agent rules based on a theoretically rooted structure that captures basic behavioural processes. Essential components of such a structure involve needs, decision-making processes and learning. Such a structure

Analog circuit design art, science and personalities

CERN Document Server

Williams, Jim

1991-01-01

This book is far more than just another tutorial or reference guide - it's a tour through the world of analog design, combining theory and applications with the philosophies behind the design process. Readers will learn how leading analog circuit designers approach problems and how they think about solutions to those problems. They'll also learn about the `analog way' - a broad, flexible method of thinking about analog design tasks.A comprehensive and useful guide to analog theory and applications. Covers visualizing the operation of analog circuits. Looks at how to rap

Resistive RAMs as analog trimming elements

Science.gov (United States)

Aziza, H.; Perez, A.; Portal, J. M.

2018-04-01

This work investigates the use of Resistive Random Access Memory (RRAM) as an analog trimming device. The analog storage feature of the RRAM cell is evaluated and the ability of the RRAM to hold several resistance states is exploited to propose analog trim elements. To modulate the memory cell resistance, a series of short programming pulses are applied across the RRAM cell allowing a fine calibration of the RRAM resistance. The RRAM non volatility feature makes the analog device powers up already calibrated for the system in which the analog trimmed structure is embedded. To validate the concept, a test structure consisting of a voltage reference is evaluated.

Fast multichannel analog storage system

International Nuclear Information System (INIS)

Freytag, D.R.

1982-11-01

A Multichannel Analog Storage System based on a commercial 32-channel parallel in/serial out (PISO) analog shift register is described. The basic unit is a single width CAMAC module containing 512 analog cells and the associated logic for data storage and subsequent readout. At sampling rates of up to 30 MHz the signals are strobed directly into the PISO. At higher rates signals are strobed into a fast presampling stage and subsequently transferred in block form into an array of PISO's. Sampling rates of 300 MHz have been achieved with the present device and 1000 MHz are possible with improved signal drivers. The system is well suited for simultaneous handling of many signal channels with moderate numbers of samples in each channel. RMS noise over full scale signal has been measured as 1:3000 (approx. = 11 bit). However, nonlinearities in the response and differences in sensitivity of the analog cells require an elaborate calibration system in order to realize 11 bit accuracy for the analog information

Elite Capture and Corruption in two Villages in Bengkulu Province, Sumatra.

Science.gov (United States)

Lucas, Anton

This paper examines leadership, elite capture and corruption in two villages in Sumatra. It compares implementation and outcomes of several conservation and development projects in the context of democratization and decentralization reforms introduced in Indonesia since 1998. In examining aspects of elite control and elite capture, this paper focuses on the activities of local elites, particularly village officials, who use their positions to monopolize planning and management of projects that were explicitly intended to incorporate participatory and accountability features. While elites' use of authority and influence to benefit personally from their roles clearly reflects elite capture, there are nonetheless members of elite groups in these case studies who use their control of projects to broad community benefit. In both villages there is considerable friction between villagers and elites as well as among members of the local elite themselves over control of local resources. Differences in the structure of these cross-cutting internal relationships and of ties between local authorities and outside government and non-government agents largely explain the differences in degree of elite capture and its outcomes in the two cases.

Web Archives for the Analog Archivist: Using Webpages Archived by the Internet Archive to Improve Processing and Description

OpenAIRE

Gelfand, Aleksandr

2018-01-01

Twenty years ago the Internet Archive was founded with the wide-ranging mission of providing universal access to all knowledge. In the two decades since, that organization has captured and made accessible over 150 billion websites. By incorporating the use of Internet Archive's Wayback Machine into their workflows, archivists working primarily with analog records may enhance their ability in such tasks as the construction of a processing plan, the creation of more accurate historical descript...

Electrical Circuits and Water Analogies

Science.gov (United States)

Smith, Frederick A.; Wilson, Jerry D.

1974-01-01

Briefly describes water analogies for electrical circuits and presents plans for the construction of apparatus to demonstrate these analogies. Demonstrations include series circuits, parallel circuits, and capacitors. (GS)

Producing and Recognizing Analogical Relations

Science.gov (United States)

Lipkens, Regina; Hayes, Steven C

2009-01-01

Analogical reasoning is an important component of intelligent behavior, and a key test of any approach to human language and cognition. Only a limited amount of empirical work has been conducted from a behavior analytic point of view, most of that within Relational Frame Theory (RFT), which views analogy as a matter of deriving relations among relations. The present series of four studies expands previous work by exploring the applicability of this model of analogy to topography-based rather than merely selection-based responses and by extending the work into additional relations, including nonsymmetrical ones. In each of the four studies participants pretrained in contextual control over nonarbitrary stimulus relations of sameness and opposition, or of sameness, smaller than, and larger than, learned arbitrary stimulus relations in the presence of these relational cues and derived analogies involving directly trained relations and derived relations of mutual and combinatorial entailment, measured using a variety of productive and selection-based measures. In Experiment 1 participants successfully recognized analogies among stimulus networks containing same and opposite relations; in Experiment 2 analogy was successfully used to extend derived relations to pairs of novel stimuli; in Experiment 3 the procedure used in Experiment 1 was extended to nonsymmetrical comparative relations; in Experiment 4 the procedure used in Experiment 2 was extended to nonsymmetrical comparative relations. Although not every participant showed the effects predicted, overall the procedures occasioned relational responses consistent with an RFT account that have not yet been demonstrated in a behavior-analytic laboratory setting, including productive responding on the basis of analogies. PMID:19230515

Capture of lipopolysaccharide (endotoxin) by the blood clot: a comparative study.

Science.gov (United States)

Armstrong, Margaret T; Rickles, Frederick R; Armstrong, Peter B

2013-01-01

In vertebrates and arthropods, blood clotting involves the establishment of a plug of aggregated thrombocytes (the cellular clot) and an extracellular fibrillar clot formed by the polymerization of the structural protein of the clot, which is fibrin in mammals, plasma lipoprotein in crustaceans, and coagulin in the horseshoe crab, Limulus polyphemus. Both elements of the clot function to staunch bleeding. Additionally, the extracellular clot functions as an agent of the innate immune system by providing a passive anti-microbial barrier and microbial entrapment device, which functions directly at the site of wounds to the integument. Here we show that, in addition to these passive functions in immunity, the plasma lipoprotein clot of lobster, the coagulin clot of Limulus, and both the platelet thrombus and the fibrin clot of mammals (human, mouse) operate to capture lipopolysaccharide (LPS, endotoxin). The lipid A core of LPS is the principal agent of gram-negative septicemia, which is responsible for more than 100,000 human deaths annually in the United States and is similarly toxic to arthropods. Quantification using the Limulus Amebocyte Lysate (LAL) test shows that clots capture significant quantities of LPS and fluorescent-labeled LPS can be seen by microscopy to decorate the clot fibrils. Thrombi generated in the living mouse accumulate LPS in vivo. It is suggested that capture of LPS released from gram-negative bacteria entrapped by the blood clot operates to protect against the disease that might be caused by its systemic dispersal.

Capture of lipopolysaccharide (endotoxin by the blood clot: a comparative study.

Directory of Open Access Journals (Sweden)

Margaret T Armstrong

Full Text Available In vertebrates and arthropods, blood clotting involves the establishment of a plug of aggregated thrombocytes (the cellular clot and an extracellular fibrillar clot formed by the polymerization of the structural protein of the clot, which is fibrin in mammals, plasma lipoprotein in crustaceans, and coagulin in the horseshoe crab, Limulus polyphemus. Both elements of the clot function to staunch bleeding. Additionally, the extracellular clot functions as an agent of the innate immune system by providing a passive anti-microbial barrier and microbial entrapment device, which functions directly at the site of wounds to the integument. Here we show that, in addition to these passive functions in immunity, the plasma lipoprotein clot of lobster, the coagulin clot of Limulus, and both the platelet thrombus and the fibrin clot of mammals (human, mouse operate to capture lipopolysaccharide (LPS, endotoxin. The lipid A core of LPS is the principal agent of gram-negative septicemia, which is responsible for more than 100,000 human deaths annually in the United States and is similarly toxic to arthropods. Quantification using the Limulus Amebocyte Lysate (LAL test shows that clots capture significant quantities of LPS and fluorescent-labeled LPS can be seen by microscopy to decorate the clot fibrils. Thrombi generated in the living mouse accumulate LPS in vivo. It is suggested that capture of LPS released from gram-negative bacteria entrapped by the blood clot operates to protect against the disease that might be caused by its systemic dispersal.

Challenges in Using Analogies

Science.gov (United States)

Lin, Shih-Yin; Singh, Chandralekha

2011-01-01

Learning physics requires understanding the applicability of fundamental principles in a variety of contexts that share deep features. One way to help students learn physics is via analogical reasoning. Students can be taught to make an analogy between situations that are more familiar or easier to understand and another situation where the same…

The Micro-Category Account of Analogy

Science.gov (United States)

Green, Adam E.; Fugelsang, Jonathan A.; Kraemer, David J. M.; Dunbar, Kevin N.

2008-01-01

Here, we investigate how activation of mental representations of categories during analogical reasoning influences subsequent cognitive processing. Specifically, we present and test the central predictions of the "Micro-Category" account of analogy. This account emphasizes the role of categories in aligning terms for analogical mapping. In a…

Priming analogical reasoning with false memories.

Science.gov (United States)

Howe, Mark L; Garner, Sarah R; Threadgold, Emma; Ball, Linden J

2015-08-01

Like true memories, false memories are capable of priming answers to insight-based problems. Recent research has attempted to extend this paradigm to more advanced problem-solving tasks, including those involving verbal analogical reasoning. However, these experiments are constrained inasmuch as problem solutions could be generated via spreading activation mechanisms (much like false memories themselves) rather than using complex reasoning processes. In three experiments we examined false memory priming of complex analogical reasoning tasks in the absence of simple semantic associations. In Experiment 1, we demonstrated the robustness of false memory priming in analogical reasoning when backward associative strength among the problem terms was eliminated. In Experiments 2a and 2b, we extended these findings by demonstrating priming on newly created homonym analogies that can only be solved by inhibiting semantic associations within the analogy. Overall, the findings of the present experiments provide evidence that the efficacy of false memory priming extends to complex analogical reasoning problems.

An emergent approach to analogical inference

Science.gov (United States)

Thibodeau, Paul H.; Flusberg, Stephen J.; Glick, Jeremy J.; Sternberg, Daniel A.

2013-03-01

In recent years, a growing number of researchers have proposed that analogy is a core component of human cognition. According to the dominant theoretical viewpoint, analogical reasoning requires a specific suite of cognitive machinery, including explicitly coded symbolic representations and a mapping or binding mechanism that operates over these representations. Here we offer an alternative approach: we find that analogical inference can emerge naturally and spontaneously from a relatively simple, error-driven learning mechanism without the need to posit any additional analogy-specific machinery. The results also parallel findings from the developmental literature on analogy, demonstrating a shift from an initial reliance on surface feature similarity to the use of relational similarity later in training. Variants of the model allow us to consider and rule out alternative accounts of its performance. We conclude by discussing how these findings can potentially refine our understanding of the processes that are required to perform analogical inference.

Children's analogical reasoning about natural phenomena.

Science.gov (United States)

Pauen, S; Wilkening, F

1997-10-01

This report investigates children's analogical reasoning in a physics task, using an analogy generated by the children rather than by the experimenter. A total of 127 elementary school children took part in three related studies. Children learned to predict the behavior of a balance scale. Later, they were asked to solve a force interaction problem. Two versions of the balance scale training were devised: version A suggested an incorrect solution to the target problem (negative analogy), and version B suggested a correct solution to the target problem (positive analogy). In Study 1, 9- to 10-year-olds showed spontaneous transfer in both training conditions. In Study 2, 7-year-olds did not show any transfer in the positive analogy condition. Study 3 revealed that the lack of transfer in younger children was not due to a failure either to notice the analogy or to perform the mapping. Instead, 7-year-olds transferred only selected aspects of the correct solution. Copyright 1997 Academic Press.

Working memory predicts children's analogical reasoning.

Science.gov (United States)

Simms, Nina K; Frausel, Rebecca R; Richland, Lindsey E

2018-02-01

Analogical reasoning is the cognitive skill of drawing relationships between representations, often between prior knowledge and new representations, that allows for bootstrapping cognitive and language development. Analogical reasoning proficiency develops substantially during childhood, although the mechanisms underlying this development have been debated, with developing cognitive resources as one proposed mechanism. We explored the role of executive function (EF) in supporting children's analogical reasoning development, with the goal of determining whether predicted aspects of EF were related to analogical development at the level of individual differences. We assessed 5- to 11-year-old children's working memory, inhibitory control, and cognitive flexibility using measures from the National Institutes of Health Toolbox Cognition battery. Individual differences in children's working memory best predicted performance on an analogical mapping task, even when controlling for age, suggesting a fundamental interrelationship between analogical reasoning and working memory development. These findings underscore the need to consider cognitive capacities in comprehensive theories of children's reasoning development. Copyright © 2017 Elsevier Inc. All rights reserved.

Process and circuiting arrangement for the conversion of analog signals to digital signals and digital signals to analog signals

International Nuclear Information System (INIS)

Wintzer, K.

1977-01-01

Process for analog-to-digital and digital-to-analog conversion in telecommunication systems whose outstations each have an analog transmitter and an analog receiver. The invention illustrates a method of reducing the power demand of the converters at times when no conversion processes take place. (RW) [de

Analogies and the 5E Model

Science.gov (United States)

Orgill, Mary Kay; Thomas, Megan

2007-01-01

Science classes are full of abstract or challenging concepts that are easier to understand if an analogy is used to illustrate the points. Effective analogies motivate students, clarify students' thinking, help students overcome misconceptions, and give students ways to visualize abstract concepts. When they are used appropriately, analogies can…

How Analogy Drives Physics

International Nuclear Information System (INIS)

Hofstadter, Doug

2004-01-01

Many new ideas in theoretical physics come from analogies to older ideas in physics. For instance, the abstract notion of 'isospin' (or isotopic spin) originated in the prior concept of 'spin' (quantized angular momentum); likewise, the concept of 'phonon' (quantum of sound, or quantized collective excitation of a crystal) was based on the prior concept of 'photon' (quantum of light, or quantized element of the electromagnetic field). But these two examples, far from being exceptions, in fact represent the bread and butter of inventive thinking in physics. In a nutshell, intraphysics analogy-making -- borrowing by analogy with something already known in another area of physics -- is central to the progress of physics. The aim of this talk is to reveal the pervasiveness -- indeed, the indispensability -- of this kind of semi-irrational, wholly intuitive type of thinking (as opposed to more deductive mathematical inference) in the mental activity known as 'doing physics'. Speculations as to why wild analogical leaps are so crucial to the act of discovery in physics (as opposed to other disciplines) will be offered.

CCR 20th Anniversary Commentary: Immune-Related Response Criteria--Capturing Clinical Activity in Immuno-Oncology.

Science.gov (United States)

Hoos, Axel; Wolchok, Jedd D; Humphrey, Rachel W; Hodi, F Stephen

2015-11-15

To evaluate antitumor responses to chemotherapeutic agents, investigators would typically rely upon Response Evaluation Criteria in Solid Tumors (RECIST) or modified WHO criteria, which do not comprehensively capture responses with immunotherapeutic agents. In the December 1, 2009, issue of Clinical Cancer Research, Wolchok and colleagues reported their development of novel criteria, designated "Immune-related Response Criteria" (irRC), designed to better capture the response patterns observed with immunotherapies. Broad use of the irRC since then has allowed for a more comprehensive evaluation of immunotherapies in clinical trials, indicating that their concepts can be used in conjunction with either RECIST or WHO, and has shown irRC to be a powerful tool for improved clinical investigation. See related article by Wolchok et al., Clin Cancer Res 2009;15(23) December 1, 2009;7412-20. ©2015 American Association for Cancer Research.

Component Processes in Analogical Reasoning

Science.gov (United States)

Sternberg, Robert J.

1977-01-01

Describes alternative theoretical positions regarding (a) the component information processes used in analogical reasoning and (b) strategies for combining these processes. Also presents results from three experiments on analogical reasoning. (Author/RK)

Is the link from working memory to analogy causal? No analogy improvements following working memory training gains.

Directory of Open Access Journals (Sweden)

J Elizabeth Richey

Full Text Available Analogical reasoning has been hypothesized to critically depend upon working memory through correlational data, but less work has tested this relationship through experimental manipulation. An opportunity for examining the connection between working memory and analogical reasoning has emerged from the growing, although somewhat controversial, body of literature suggests complex working memory training can sometimes lead to working memory improvements that transfer to novel working memory tasks. This study investigated whether working memory improvements, if replicated, would increase analogical reasoning ability. We assessed participants' performance on verbal and visual analogy tasks after a complex working memory training program incorporating verbal and spatial tasks. Participants' improvements on the working memory training tasks transferred to other short-term and working memory tasks, supporting the possibility of broad effects of working memory training. However, we found no effects on analogical reasoning. We propose several possible explanations for the lack of an impact of working memory improvements on analogical reasoning.

Is the link from working memory to analogy causal? No analogy improvements following working memory training gains.

Science.gov (United States)

Richey, J Elizabeth; Phillips, Jeffrey S; Schunn, Christian D; Schneider, Walter

2014-01-01

Analogical reasoning has been hypothesized to critically depend upon working memory through correlational data, but less work has tested this relationship through experimental manipulation. An opportunity for examining the connection between working memory and analogical reasoning has emerged from the growing, although somewhat controversial, body of literature suggests complex working memory training can sometimes lead to working memory improvements that transfer to novel working memory tasks. This study investigated whether working memory improvements, if replicated, would increase analogical reasoning ability. We assessed participants' performance on verbal and visual analogy tasks after a complex working memory training program incorporating verbal and spatial tasks. Participants' improvements on the working memory training tasks transferred to other short-term and working memory tasks, supporting the possibility of broad effects of working memory training. However, we found no effects on analogical reasoning. We propose several possible explanations for the lack of an impact of working memory improvements on analogical reasoning.

Is the Link from Working Memory to Analogy Causal? No Analogy Improvements following Working Memory Training Gains

Science.gov (United States)

Richey, J. Elizabeth; Phillips, Jeffrey S.; Schunn, Christian D.; Schneider, Walter

2014-01-01

Analogical reasoning has been hypothesized to critically depend upon working memory through correlational data [1], but less work has tested this relationship through experimental manipulation [2]. An opportunity for examining the connection between working memory and analogical reasoning has emerged from the growing, although somewhat controversial, body of literature suggests complex working memory training can sometimes lead to working memory improvements that transfer to novel working memory tasks. This study investigated whether working memory improvements, if replicated, would increase analogical reasoning ability. We assessed participants’ performance on verbal and visual analogy tasks after a complex working memory training program incorporating verbal and spatial tasks [3], [4]. Participants’ improvements on the working memory training tasks transferred to other short-term and working memory tasks, supporting the possibility of broad effects of working memory training. However, we found no effects on analogical reasoning. We propose several possible explanations for the lack of an impact of working memory improvements on analogical reasoning. PMID:25188356

Beginning analog electronics through projects

CERN Document Server

Singmin, Andrew

2001-01-01

Analog electronics is the simplest way to start a fun, informative, learning program. Beginning Analog Electronics Through Projects, Second Edition was written with the needs of beginning hobbyists and students in mind. This revision of Andrew Singmin's popular Beginning Electronics Through Projects provides practical exercises, building techniques, and ideas for useful electronics projects. Additionally, it features new material on analog and digital electronics, and new projects for troubleshooting test equipment.Published in the tradition of Beginning Electronics Through Projects an

Evaluating Water Demand Using Agent-Based Modeling

Science.gov (United States)

Lowry, T. S.

2004-12-01

The supply and demand of water resources are functions of complex, inter-related systems including hydrology, climate, demographics, economics, and policy. To assess the safety and sustainability of water resources, planners often rely on complex numerical models that relate some or all of these systems using mathematical abstractions. The accuracy of these models relies on how well the abstractions capture the true nature of the systems interactions. Typically, these abstractions are based on analyses of observations and/or experiments that account only for the statistical mean behavior of each system. This limits the approach in two important ways: 1) It cannot capture cross-system disruptive events, such as major drought, significant policy change, or terrorist attack, and 2) it cannot resolve sub-system level responses. To overcome these limitations, we are developing an agent-based water resources model that includes the systems of hydrology, climate, demographics, economics, and policy, to examine water demand during normal and extraordinary conditions. Agent-based modeling (ABM) develops functional relationships between systems by modeling the interaction between individuals (agents), who behave according to a probabilistic set of rules. ABM is a "bottom-up" modeling approach in that it defines macro-system behavior by modeling the micro-behavior of individual agents. While each agent's behavior is often simple and predictable, the aggregate behavior of all agents in each system can be complex, unpredictable, and different than behaviors observed in mean-behavior models. Furthermore, the ABM approach creates a virtual laboratory where the effects of policy changes and/or extraordinary events can be simulated. Our model, which is based on the demographics and hydrology of the Middle Rio Grande Basin in the state of New Mexico, includes agent groups of residential, agricultural, and industrial users. Each agent within each group determines its water usage

Demonstrations of analog-to-digital conversion using a frequency domain stretched processor.

Science.gov (United States)

Reibel, Randy Ray; Harrington, Calvin; Dahl, Jason; Ostrander, Charles; Roos, Peter Aaron; Berg, Trenton; Mohan, R Krishna; Neifeld, Mark A; Babbitt, Wm R

2009-07-06

The first proof-of-concept demonstrations are presented for a broadband photonic-assisted analog-to-digital converter (ADC) based on spatial spectral holography (SSH). The SSH-ADC acts as a frequency-domain stretch processor converting high bandwidth input signals to low bandwidth output signals, allowing the system to take advantage of high performance, low bandwidth electronic ADCs. Demonstrations with 50 MHz effective bandwidth are shown to highlight basic performance with approximately 5 effective bits of vertical resolution. Signal capture with 1600 MHz effective bandwidth is also shown. Because some SSH materials span over 100 GHz and have large time apertures (approximately 10 micros), this technique holds promise as a candidate for the next generation of ADCs.

Analog circuit design art, science, and personalities

CERN Document Server

Williams, Jim

1991-01-01

Analog Circuit Design: Art, Science, and Personalities discusses the many approaches and styles in the practice of analog circuit design. The book is written in an informal yet informative manner, making it easily understandable to those new in the field. The selection covers the definition, history, current practice, and future direction of analog design; the practice proper; and the styles in analog circuit design. The book also includes the problems usually encountered in analog circuit design; approach to feedback loop design; and other different techniques and applications. The text is

Multivalent contrast agents based on Gd-DTPA-terminated poly (propylene imine) dendrimers for Magnetic Resonance Imaging

NARCIS (Netherlands)

Langereis, S.; Lussanet, de Q.G; Genderen, van M.H.P.; Backes, W.H.; Meijer, E.W.

2004-01-01

A convenient methodol. has been developed for the synthesis of gadolinium-diethylenetriaminepentaacetic acid (Gd-DTPA)-terminated poly(propylene imine) dendrimers as contrast agents for magnetic resonance imaging (MRI). In our strategy, isocyanate-activated, tert-butyl-protected DTPA analogs were

Evaluation of tricine and EDDA as Co-ligands for 99mTc-labeled HYNIC-MSH analogs for melanoma imaging.

Science.gov (United States)

Garcia, Maria Fernanda; Zhang, Xiuli; Gallazzi, Fabio; Fernandez, Marcelo; Moreno, Maria; Gambini, Juan Pablo; Porcal, Williams; Cabral, Pablo; Quinn, Thomas P

2015-01-01

Several radiolabeled alpha-melanocyte stimulating hormone (α-MSH) analogs have been studied for their abilities to target melanoma tumor cells through specific recognition and binding to the melanocortin receptor 1 (MCR1). In this work, a lactam bridgecyclized α-MSH analog was labeled with (99m) via the hydrazinonicotinamide (HYNIC) chelator and characterized for its melanoma tumor targeting properties. The bifunctional chelating agent HYNIC-Boc was attached to the N-terminus of the MSH peptide followed by the lactam cyclization, resulting in the HYNIC-cyc-MSH analog. The lactam cyclized peptide displayed high affinity and specificity for MC1-receptors present on B16/F1 melanoma tumor cells, exhibiting an IC50 of 6.48 nM. HYNIC-cyc-MSH was radiolabeled with (99m)Tc using two common co-ligands, tricine and EDDA. In vitro, the radiochemical stability, cell binding and efflux properties were similar between the peptides radiolabeled with tricine and EDDA as co-ligands. In vivo, biodistribution studies (n=4) demonstrated that (99m)Tc- HYNIC-cyc-MSH/tricine had superior tumor to muscle and tumor to blood ratios than (99m)Tc-HYNIC-cyc-MSH/EDDA at early time points. Planar gamma imaging of melanoma bearing mice showed that 99mTc-HYNIC-cyc-MSH/tricine was able to clearly visualize tumors, underscoring the potential utility of (99m)Tc labeled lactam cyclized MSH molecules as melanoma imaging agents.

Synthetic Analogs of Phospholipid Metabolites as Antimalarials.

Science.gov (United States)

1979-07-01

phosphatidic acid analogs containing ether and phosphonate groups; completely non- hydrolyzable lecithin analogs containing phosphinate and ether groups...substance is a completely non- hydrolyzable analog of lecithin containing ether and phosphonate moieties instead of the normally labile carboxylic and...and also ant-i-phospholipase C (clostridial enzyme) activity. This substance Is a completely non- hydrolyzable analog of lecithin containing ether

FGF growth factor analogs

Science.gov (United States)

Zamora, Paul O [Gaithersburg, MD; Pena, Louis A [Poquott, NY; Lin, Xinhua [Plainview, NY; Takahashi, Kazuyuki [Germantown, MD

2012-07-24

The present invention provides a fibroblast growth factor heparin-binding analog of the formula: ##STR00001## where R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5, X, Y and Z are as defined, pharmaceutical compositions, coating compositions and medical devices including the fibroblast growth factor heparin-binding analog of the foregoing formula, and methods and uses thereof.

Progress of study on the dopamine D4 receptor imaging agent

International Nuclear Information System (INIS)

Tian Haibin; Zhang Lan; Zhang Chunfu; Li Junling; Yin Duanzhi

2001-01-01

Dopamine receptors were originally classified into five receptors subtypes, the dopamine D 4 receptor was included. Schizophrenic pathophysiology may be associated with expression and function of the dopamine D 4 receptor; it is of great importance to study the imaging agent of dopamine D 4 receptor. The study on radioactivity distribution and metabolize of radioligand remains hampered by the lack radioligand for the D 4 receptor which can be labeled using suitable nuclei. This paper reviews the progress of study on the dopamine D 4 receptor imaging agent, with particular emphasis vary nuclei, for example 11 C, 18 F, 123 I, labeled D 4 receptor ligands, antagonists and analogs as PET or SPECT imaging agents. Authors estimated affinity and selectivity of radioligands for the dopamine D 4 receptor in laboratory animal tests

Synthesis and biological evaluation of boronated polyglycerol dendrimers as potential agent for neutron capture therapy

International Nuclear Information System (INIS)

Silva, Gerald S.; Camillo, Maria A.P.; Higa, Olga Z.; Pugliesi, Reynaldo; Fermamdes, Edson G.R.; Queiroz, Alvaro A.A. de

2005-01-01

In this work, the polyglycerol dendrimer (PGLD) generation 5 was used to obtain a boronated macromolecule for boron neutron capture therapy. The PGLD dendrimer was synthesized by the ring opening polymerization of deprotonated glycidol using polyglycerol as core functionality in a step-growth processes denominated divergent synthesis. The PGLD dendritic structure was confirmed by gel permeation chromatography, nuclear magnetic resonance ( 1 H-NMR, 13 C-NMR) and matrix assisted laser desorption/ionization techniques. The synthesized dendrimer presented low dispersion in molecular weights (M w /M n = 1.05) and a degree of branching of 0.82, which characterize the polymer dendritic structure. Quantitative neutron capture radiography was used to investigate the boron-10 enrichment of the polyglycerol dendrimer. The in vitro cytotoxicity to Chinese hamster ovary cells of 10 B-PGLD dendrimer indicate lower cytotoxicity, suggesting that the macromolecule is a biocompatible material. (author)

Towards Automated Bargaining in Electronic Markets: A Partially Two-Sided Competition Model

Science.gov (United States)

Gatti, Nicola; Lazaric, Alessandro; Restelli, Marcello

This paper focuses on the prominent issue of automating bargaining agents within electronic markets. Models of bargaining in literature deal with settings wherein there are only two agents and no model satisfactorily captures settings in which there is competition among buyers, being they more than one, and analogously among sellers. In this paper, we extend the principal bargaining protocol, i.e. the alternating-offers protocol, to capture bargaining in markets. The model we propose is such that, in presence of a unique buyer and a unique seller, agents' equilibrium strategies are those in the original protocol. Moreover, we game theoretically study the considered game providing the following results: in presence of one-sided competition (more buyers and one seller or vice versa) we provide agents' equilibrium strategies for all the values of the parameters, in presence of two-sided competition (more buyers and more sellers) we provide an algorithm that produce agents' equilibrium strategies for a large set of the parameters and we experimentally evaluate its effectiveness.

Structure problems in the analog computation

International Nuclear Information System (INIS)

Braffort, P.L.

1957-01-01

The recent mathematical development showed the importance of elementary structures (algebraic, topological, etc.) in abeyance under the great domains of classical analysis. Such structures in analog computation are put in evidence and possible development of applied mathematics are discussed. It also studied the topological structures of the standard representation of analog schemes such as additional triangles, integrators, phase inverters and functions generators. The analog method gives only the function of the variable: time, as results of its computations. But the course of computation, for systems including reactive circuits, introduces order structures which are called 'chronological'. Finally, it showed that the approximation methods of ordinary numerical and digital computation present the same structure as these analog computation. The structure analysis permits fruitful comparisons between the several domains of applied mathematics and suggests new important domains of application for analog method. (M.P.)

Molecular modeling of fentanyl analogs

Directory of Open Access Journals (Sweden)

LJILJANA DOSEN-MICOVIC

2004-11-01

Full Text Available Fentanyl is a highly potent and clinically widely used narcotic analgesic. A large number of its analogs have been synthesized, some of which (sufentanil and alfentanyl are also in clinical use. Theoretical studies, in recent years, afforded a better understanding of the structure-activity relationships of this class of opiates and allowed insight into the molecular mechanism of the interactions of fentanyl analogs with their receptors. An overview of the current computational techniques for modeling fentanyl analogs, their receptors and ligand-receptor interactions is presented in this paper.

Terrestrial Analogs to Mars

Science.gov (United States)

Farr, T. G.; Arcone, S.; Arvidson, R. W.; Baker, V.; Barlow, N. G.; Beaty, D.; Bell, M. S.; Blankenship, D. D.; Bridges, N.; Briggs, G.; Bulmer, M.; Carsey, F.; Clifford, S. M.; Craddock, R. A.; Dickerson, P. W.; Duxbury, N.; Galford, G. L.; Garvin, J.; Grant, J.; Green, J. R.; Gregg, T. K. P.; Guinness, E.; Hansen, V. L.; Hecht, M. H.; Holt, J.; Howard, A.; Keszthelyi, L. P.; Lee, P.; Lanagan, P. D.; Lentz, R. C. F.; Leverington, D. W.; Marinangeli, L.; Moersch, J. E.; Morris-Smith, P. A.; Mouginis-Mark, P.; Olhoeft, G. R.; Ori, G. G.; Paillou, P.; Reilly, J. F., II; Rice, J. W., Jr.; Robinson, C. A.; Sheridan, M.; Snook, K.; Thomson, B. J.; Watson, K.; Williams, K.; Yoshikawa, K.

2002-08-01

It is well recognized that interpretations of Mars must begin with the Earth as a reference. The most successful comparisons have focused on understanding geologic processes on the Earth well enough to extrapolate to Mars' environment. Several facets of terrestrial analog studies have been pursued and are continuing. These studies include field workshops, characterization of terrestrial analog sites, instrument tests, laboratory measurements (including analysis of Martian meteorites), and computer and laboratory modeling. The combination of all these activities allows scientists to constrain the processes operating in specific terrestrial environments and extrapolate how similar processes could affect Mars. The Terrestrial Analogs for Mars Community Panel has considered the following two key questions: (1) How do terrestrial analog studies tie in to the Mars Exploration Payload Assessment Group science questions about life, past climate, and geologic evolution of Mars, and (2) How can future instrumentation be used to address these questions. The panel has considered the issues of data collection, value of field workshops, data archiving, laboratory measurements and modeling, human exploration issues, association with other areas of solar system exploration, and education and public outreach activities.

Expert analogy use in a naturalistic setting

Science.gov (United States)

Kretz, Donald R.; Krawczyk, Daniel C.

2014-01-01

The use of analogy is an important component of human cognition. The type of analogy we produce and communicate depends heavily on a number of factors, such as the setting, the level of domain expertise present, and the speaker's goal or intent. In this observational study, we recorded economics experts during scientific discussion and examined the categorical distance and structural depth of the analogies they produced. We also sought to characterize the purpose of the analogies that were generated. Our results supported previous conclusions about the infrequency of superficial similarity in subject-generated analogs, but also showed that distance and depth characteristics were more evenly balanced than in previous observational studies. This finding was likely due to the nature of the goals of the participants, as well as the broader nature of their expertise. An analysis of analogical purpose indicated that the generation of concrete source examples of more general target concepts was most prevalent. We also noted frequent instances of analogies intended to form visual images of source concepts. Other common purposes for analogies were the addition of colorful speech, inclusion (i.e., subsumption) of a target into a source concept, or differentiation between source and target concepts. We found no association between depth and either of the other two characteristics, but our findings suggest a relationship between purpose and distance; i.e., that visual imagery typically entailed an outside-domain source whereas exemplification was most frequently accomplished using within-domain analogies. Overall, we observed a rich and diverse set of spontaneously produced analogical comparisons. The high degree of expertise within the observed group along with the richly comparative nature of the economics discipline likely contributed to this analogical abundance. PMID:25505437

Expert Analogy Use in a Naturalistic Setting

Directory of Open Access Journals (Sweden)

Donald R Kretz

2014-11-01

Full Text Available The use of analogy is an important component of human cognition. The type of analogy we produce and communicate depends heavily on a number of factors, such as the setting, the level of domain expertise present, and the speaker’s goal or intent. In this observational study, we recorded economics experts during scientific discussion and examined the categorical distance and structural depth of the analogies they produced. We also sought to characterize the purpose of the analogies that were generated. Our results supported previous conclusions about the infrequency of superficial similarity in subject-generated analogs, but also showed that distance and depth characteristics were more evenly balanced than in previous observational studies. This finding was likely due to the nature of the goals of the participants, as well as the broader nature of their expertise. An analysis of analogical purpose indicated that the generation of concrete source examples of more general target concepts was most prevalent. We also noted frequent instances of analogies intended to form visual images of source concepts. Other common purposes for analogies were the addition of colorful speech, inclusion (i.e., subsumption of a target into a source concept, or differentiation between source and target concepts. We found no association between depth and either of the other two characteristics, but our findings suggest a relationship between purpose and distance; i.e., that visual imagery typically entailed an outside-domain source whereas exemplification was most frequently accomplished using within-domain analogies. Overall, we observed a rich and diverse set of spontaneously produced analogical comparisons. The high degree of expertise within the observed group along with the richly comparative nature of the economics discipline likely contributed to this analogical abundance.

A bilateral frontoparietal network underlies visuospatial analogical reasoning.

Science.gov (United States)

Watson, Christine E; Chatterjee, Anjan

2012-02-01

Our ability to reason by analogy facilitates problem solving and allows us to communicate ideas efficiently. In this study, we examined the neural correlates of analogical reasoning and, more specifically, the contribution of rostrolateral prefrontal cortex (RLPFC) to reasoning. This area of the brain has been hypothesized to integrate relational information, as in analogy, or the outcomes of subgoals, as in multi-tasking and complex problem solving. Using fMRI, we compared visuospatial analogical reasoning to a control task that was as complex and difficult as the analogies and required the coordination of subgoals but not the integration of relations. We found that analogical reasoning more strongly activated bilateral RLPFC, suggesting that anterior prefrontal cortex is preferentially recruited by the integration of relational knowledge. Consistent with the need for inhibition during analogy, bilateral, and particularly right, inferior frontal gyri were also more active during analogy. Finally, greater activity in bilateral inferior parietal cortex during the analogy task is consistent with recent evidence for the neural basis of spatial relation knowledge. Together, these findings indicate that a network of frontoparietal areas underlies analogical reasoning; we also suggest that hemispheric differences may emerge depending on the visuospatial or verbal/semantic nature of the analogies. Copyright © 2011 Elsevier Inc. All rights reserved.

Neural correlates of creativity in analogical reasoning.

Science.gov (United States)

Green, Adam E; Kraemer, David J M; Fugelsang, Jonathan A; Gray, Jeremy R; Dunbar, Kevin N

2012-03-01

Brain-based evidence has implicated the frontal pole of the brain as important for analogical mapping. Separately, cognitive research has identified semantic distance as a key determinant of the creativity of analogical mapping (i.e., more distant analogies are generally more creative). Here, we used functional magnetic resonance imaging to assess brain activity during an analogy generation task in which we varied the semantic distance of analogical mapping (as derived quantitatively from a latent semantic analysis). Data indicated that activity within an a priori region of interest in left frontopolar cortex covaried parametrically with increasing semantic distance, even after removing effects of task difficulty. Results implicate increased recruitment of frontopolar cortex as a mechanism for integrating semantically distant information to generate solutions in creative analogical reasoning. 2012 APA, all rights reserved

Using Visual Analogies To Teach Introductory Statistical Concepts

Directory of Open Access Journals (Sweden)

Jessica S. Ancker

2017-07-01

Full Text Available Introductory statistical concepts are some of the most challenging to convey in quantitative literacy courses. Analogies supplemented by visual illustrations can be highly effective teaching tools. This literature review shows that to exploit the power of analogies, teachers must select analogies familiar to the audience, explicitly link the analog with the target concept, and avert misconceptions by explaining where the analogy fails. We provide guidance for instructors and a series of visual analogies for use in teaching medical and health statistics.

CMOS analog circuit design

CERN Document Server

Allen, Phillip E

1987-01-01

This text presents the principles and techniques for designing analog circuits to be implemented in a CMOS technology. The level is appropriate for seniors and graduate students familiar with basic electronics, including biasing, modeling, circuit analysis, and some familiarity with frequency response. Students learn the methodology of analog integrated circuit design through a hierarchically-oriented approach to the subject that provides thorough background and practical guidance for designing CMOS analog circuits, including modeling, simulation, and testing. The authors' vast industrial experience and knowledge is reflected in the circuits, techniques, and principles presented. They even identify the many common pitfalls that lie in the path of the beginning designer--expert advice from veteran designers. The text mixes the academic and practical viewpoints in a treatment that is neither superficial nor overly detailed, providing the perfect balance.

Triple pulse shape discrimination and capture-gated spectroscopy in a composite heterogeneous scintillator

Energy Technology Data Exchange (ETDEWEB)

Sharma, M., E-mail: mksharma@umich.edu [University of Michigan, Ann Arbor, MI 48109 (United States); Nattress, J. [University of Michigan, Ann Arbor, MI 48109 (United States); Wilhelm, K. [Pennsylvania State University, University Park, PA 16802 (United States); Jovanovic, I. [University of Michigan, Ann Arbor, MI 48109 (United States)

2017-06-11

We demonstrate an all-solid-state design for a composite heterogeneous scintillation detector sensitive to interactions with high-energy photons (gammas), fast neutrons, and thermal neutrons. The scintillator exhibits triple pulse shape discrimination, effectively separating electron recoils, fast neutron recoils, and neutron captures. This is accomplished by combining the properties of two distinct scintillators, whereby a 51-mm diameter, 51-mm tall cylinder of pulse shape discriminating plastic is wrapped by a 320-µm thick sheet of {sup 6}LiF:ZnS(Ag), optically coupling the scintillators to each other and to the photomultiplier tube. In this way, the sensitivity to neutron captures is achieved without the need to load the plastic scintillator with a capture agent. We demonstrate a figure of merit of up to 1.2 for fast neutrons/gammas and 5.7 for thermal neutrons/gammas. Intrinsic capture efficiency is found to be 0.46±0.05% and is in good agreement with simulation, while gamma rejection was 10{sup −6} with respect to the capture region and 10{sup −4} with respect to the recoil region using a 300 keVee threshold. Finally, we show an improvement in capture-gated neutron spectroscopy by rejecting accidental gamma coincidences using pulse shape discrimination in the plastic scintillator.

Frontopolar cortex mediates abstract integration in analogy.

Science.gov (United States)

Green, Adam E; Fugelsang, Jonathan A; Kraemer, David J M; Shamosh, Noah A; Dunbar, Kevin N

2006-06-22

Integration of abstractly similar relations during analogical reasoning was investigated using functional magnetic resonance imaging. Activation elicited by an analogical reasoning task that required both complex working memory and integration of abstractly similar relations was compared to activation elicited by a non-analogical task that required complex working memory in the absence of abstract relational integration. A left-sided region of the frontal pole of the brain (BA 9/10) was selectively active for the abstract relational integration component of analogical reasoning. Analogical reasoning also engaged a left-sided network of parieto-frontal regions. Activity in this network during analogical reasoning is hypothesized to reflect categorical alignment of individual component terms that make up analogies. This parieto-frontal network was also engaged by the complex control task, which involved explicit categorization, but not by a simpler control task, which did not involve categorization. We hypothesize that frontopolar cortex mediates abstract relational integration in complex reasoning while parieto-frontal regions mediate working memory processes, including manipulation of terms for the purpose of categorical alignment, that facilitate this integration.

The force of dissimilar analogies in bioethics.

Science.gov (United States)

Mertes, Heidi; Pennings, Guido

2011-04-01

Although analogical reasoning has long been a popular method of reasoning in bioethics, current literature does not sufficiently grasp its variety. We assert that the main shortcoming is the fact that an analogy's value is often judged on the extent of similarity between the source situation and the target situation, while in (bio)ethics, analogies are often used because of certain dissimilarities rather than in spite of them. We make a clear distinction between dissimilarities that aim to reinforce a similar approach in the source situation and the target situation and dissimilarities that aim to undermine or denounce a similar approach. The former kind of dissimilarity offers the analogy more normative force than if there were no dissimilarities present; this is often overlooked by authors who regard all relevant dissimilarities as detrimental to the analogy's strength. Another observation is that an evaluation of the normative force of an analogy cannot be made independently of moral principles or theories. Without these, one cannot select which elements in an analogy are morally relevant nor determine how they should be interpreted.

Anti-Plasmodium activity of ceramide analogs

Directory of Open Access Journals (Sweden)

Gatt Shimon

2004-12-01

Full Text Available Abstract Background Sphingolipids are key molecules regulating many essential functions in eukaryotic cells and ceramide plays a central role in sphingolipid metabolism. A sphingolipid metabolism occurs in the intraerythrocytic stages of Plasmodium falciparum and is associated with essential biological processes. It constitutes an attractive and potential target for the development of new antimalarial drugs. Methods The anti-Plasmodium activity of a series of ceramide analogs containing different linkages (amide, methylene or thiourea linkages between the fatty acid part of ceramide and the sphingoid core was investigated in culture and compared to the sphingolipid analog PPMP (d,1-threo-1-phenyl-2-palmitoylamino-3-morpholino-1-propanol. This analog is known to inhibit the parasite sphingomyelin synthase activity and block parasite development by preventing the formation of the tubovesicular network that extends from the parasitophorous vacuole to the red cell membrane and delivers essential extracellular nutrients to the parasite. Results Analogs containing methylene linkage showed a considerably higher anti-Plasmodium activity (IC50 in the low nanomolar range than PPMP and their counterparts with a natural amide linkage (IC50 in the micromolar range. The methylene analogs blocked irreversibly P. falciparum development leading to parasite eradication in contrast to PPMP whose effect is cytostatic. A high sensitivity of action towards the parasite was observed when compared to their effect on the human MRC-5 cell growth. The toxicity towards parasites did not correlate with the inhibition by methylene analogs of the parasite sphingomyelin synthase activity and the tubovesicular network formation, indicating that this enzyme is not their primary target. Conclusions It has been shown that ceramide analogs were potent inhibitors of P. falciparum growth in culture. Interestingly, the nature of the linkage between the fatty acid part and the

The future of vitamin D analogs

Directory of Open Access Journals (Sweden)

Carlien eLeyssens

2014-04-01

Full Text Available The active form of vitamin D3, 1,25-dihydroxyvitamin D3, is a major regulator of bone and calcium homeostasis. In addition, this hormone also inhibits the proliferation and stimulates the differentiation of normal as well as malignant cells. Supraphysiological doses of 1,25-dihydroxyvitamin D3 are required to reduce cancer cell proliferation. However, these doses will lead in vivo to calcemic side effects such as hypercalcemia and hypercalciuria. During the last 25 years, many structural analogs of 1,25-dihydroxyvitamin D3 have been synthesized by the introduction of chemical modifications in the A-ring, central CD-ring region or side chain of 1,25-dihydroxyvitamin D3 in the hope to find molecules with a clear dissociation between the beneficial antiproliferative effects and adverse calcemic side effects. One example of such an analog with a good dissociation ratio is calcipotriol (DaivonexR, which is clinically used to treat the hyperproliferative skin disease psoriasis. Other vitamin D analogs were clinically approved for the treatment of osteoporosis or secondary hyperparathyroidism. No vitamin D analog is currently used in the clinic for the treatment of cancer although several analogs have been shown to be potent drugs in animal models of cancer. Omics studies as well as in vitro cell biological experiments unraveled basic mechanisms involved in the antineoplastic effects of vitamin D and its analogs. 1,25-dihydroxyvitamin D3 and analogs act in a cell type- and tissue-specific manner. Moreover, a blockade in the transition of the G0/1 towards S phase of the cell cycle, induction of apoptosis, inhibition of migration and invasion of tumor cells together with effects on angiogenesis and inflammation have been implicated in the pleiotropic effects of 1,25-dihydroxyvitamin D3 and its analogs. In this review we will give an overview of the action of vitamin D analogs in tumor cells and look forward how these compounds could be introduced in the

Boron neutron capture therapy for malignant melanoma: An experimental approach

Energy Technology Data Exchange (ETDEWEB)

Larsson, B.S.; Larsson, B.; Roberto, A. (Uppsala Univ. (Sweden))

1989-07-01

Previous studies have shown that some thioamides, e.g., thiouracil, are incorporated as false precursors into melanin during its synthesis. If boronated analogs of the thioamides share this property, the melanin of melanotic melanomas offers a possibility for specific tumoural uptake and retention of boron as a basis for neutron capture therapy. We report on the synthesis of boronated 1H-1,2,4-triazole-3-thiol (B-TZT), boronated 5-carboxy-2-thiouracil (B-CTU), and boronated 5-diethylaminomethyl-2-thiouracil (B-DEAMTU) and the localization of these substances in melanotic melanomas transplanted to mice. The distribution in the mice was studied by boron neutron capture radiography. B-TZT and B-CTU showed the highest tumour:normal tissue concentration ratios, with tumour:liver ratios of about 4 and tumour:muscle ratios of about 14; B-DEAMTU showed corresponding ratios of 1.4 and 5, respectively. The absolute concentration of boron in the tumours, however, was more than three times higher in the mice injected with B-TZT, compared with B-CTU. The results suggest that B-TZT may be the most promising compound of the three tested with regard to possible therapy of melanotic melanomas.

Enhancing programming logic thinking using analogy mapping

Science.gov (United States)

Sukamto, R. A.; Megasari, R.

2018-05-01

Programming logic thinking is the most important competence for computer science students. However, programming is one of the difficult subject in computer science program. This paper reports our work about enhancing students' programming logic thinking using Analogy Mapping for basic programming subject. Analogy Mapping is a computer application which converts source code into analogies images. This research used time series evaluation and the result showed that Analogy Mapping can enhance students' programming logic thinking.

A case of malignant hyperthermia captured by an anesthesia information management system.

Science.gov (United States)

Maile, Michael D; Patel, Rajesh A; Blum, James M; Tremper, Kevin K

2011-04-01

Many cases of malignant hyperthermia triggered by volatile anesthetic agents have been described. However, to our knowledge, there has not been a report describing the precise changes in physiologic data of a human suffering from this process. Here we describe a case of malignant hyperthermia in which monitoring information was frequently and accurately captured by an anesthesia information management system.

Gemini analogs of vitamin D.

Science.gov (United States)

Pazos, Gonzalo; Rivadulla, Marcos L; Pérez-García, Xenxo; Gandara, Zoila; Pérez, Manuel

2014-01-01

The Gemini analogs are the last significant contribution to the family of vitamin D derivatives in medicine, for the treatment of cancer. The first Gemini analog was characterized by two symmetric side chains at C-20. Following numerous modifications, the most active analog bears a C-23-triple bond, C-26, 27- hexafluoro substituents on one side chain and a terminal trideuteromethylhydroxy group on the other side chain. This progression was possible due to improvements in the synthetic methods for the preparation of these derivatives, which allowed for increasing molecular complexity and complete diastereoselective control at C-20 and the substituted sidechains.

A fast multichannel analog storage system

International Nuclear Information System (INIS)

Freytag, D.R.

1983-01-01

A Multichannel Analog Storage System based on a commercial 32-channel parallel in/serial out (PISO) analog shift register is described. The basic unit is a single width CAMAC module containing 512 analog cells and the associated logic for data storage and subsequent readout. At sampling rates of up to 30 MHz the signals are strobed directly into the PISO. At higher rates signals are strobed into a fast presampling stage and subsequently transferred in block form into an array of PISO's. Sampling rates of 300 MHz have been achieved with the present device and 1000 MHz are possible with improved signal drivers. The system is well suited for simultaneous handling of many signal channels with moderate numbers of samples in each channel. RMS noise over full scale signal has been measured as 1:3000 (approx. =11 bit). However, nonlinearities in the response and differences in sensitivity of the analog cells require an elaborate calibration system in order to realize 11 bit accuracy for the analog information

Rapid discovery of peptide capture candidates with demonstrated specificity for structurally similar toxins

Science.gov (United States)

Sarkes, Deborah A.; Hurley, Margaret M.; Coppock, Matthew B.; Farrell, Mikella E.; Pellegrino, Paul M.; Stratis-Cullum, Dimitra N.

2016-05-01

Peptides have emerged as viable alternatives to antibodies for molecular-based sensing due to their similarity in recognition ability despite their relative structural simplicity. Various methods for peptide capture reagent discovery exist, including phage display, yeast display, and bacterial display. One of the primary advantages of peptide discovery by bacterial display technology is the speed to candidate peptide capture agent, due to both rapid growth of bacteria and direct utilization of the sorted cells displaying each individual peptide for the subsequent round of biopanning. We have previously isolated peptide affinity reagents towards protective antigen of Bacillus anthracis using a commercially available automated magnetic sorting platform with improved enrichment as compared to manual magnetic sorting. In this work, we focus on adapting our automated biopanning method to a more challenging sort, to demonstrate the specificity possible with peptide capture agents. This was achieved using non-toxic, recombinant variants of ricin and abrin, RiVax and abrax, respectively, which are structurally similar Type II ribosomal inactivating proteins with significant sequence homology. After only two rounds of biopanning, enrichment of peptide capture candidates binding abrax but not RiVax was achieved as demonstrated by Fluorescence Activated Cell Sorting (FACS) studies. Further sorting optimization included negative sorting against RiVax, proper selection of autoMACS programs for specific sorting rounds, and using freshly made buffer and freshly thawed protein target for each round of biopanning for continued enrichment over all four rounds. Most of the resulting candidates from biopanning for abrax binding peptides were able to bind abrax but not RiVax, demonstrating that short peptide sequences can be highly specific even at this early discovery stage.

Atheism and Analogy: Aquinas Against the Atheists

OpenAIRE

Linford, Daniel J.

2014-01-01

In the 13th century, Thomas Aquinas developed two models for how humans may speak of God - either by the analogy of proportion or by the analogy of proportionality. Aquinas's doctrines initiated a theological debate concerning analogy that spanned several centuries. In the 18th century, there appeared two closely related arguments for atheism which both utilized analogy for their own purposes. In this thesis, I show that one argument, articulated by the French materialist Paul-Henri Thiry Bar...

Analog filters in nanometer CMOS

CERN Document Server

Uhrmann, Heimo; Zimmermann, Horst

2014-01-01

Starting from the basics of analog filters and the poor transistor characteristics in nanometer CMOS 10 high-performance analog filters developed by the authors in 120 nm and 65 nm CMOS are described extensively. Among them are gm-C filters, current-mode filters, and active filters for system-on-chip realization for Bluetooth, WCDMA, UWB, DVB-H, and LTE applications. For the active filters several operational amplifier designs are described. The book, furthermore, contains a review of the newest state of research on low-voltage low-power analog filters. To cover the topic of the book comprehensively, linearization issues and measurement methods for the characterization of advanced analog filters are introduced in addition. Numerous elaborate illustrations promote an easy comprehension. This book will be of value to engineers and researchers in industry as well as scientists and Ph.D students at universities. The book is also recommendable to graduate students specializing on nanoelectronics, microelectronics ...

CO 2 Capture from Dilute Gases as a Component of Modern Global Carbon Management

KAUST Repository

Jones, Christopher W.

2011-01-01

The growing atmospheric CO2 concentration and its impact on climate have motivated widespread research and development aimed at slowing or stemming anthropogenic carbon emissions. Technologies for carbon capture and sequestration (CCS) employing mass separating agents that extract and purify CO2 from flue gas emanating from large point sources such as fossil fuel-fired electricity-generating power plants are under development. Recent advances in solvents, adsorbents, and membranes for postcombust- ion CO 2 capture are described here. Specifically, room-temperature ionic liquids, supported amine materials, mixed matrix and facilitated transport membranes, and metal-organic framework materials are highlighted. In addition, the concept of extracting CO2 directly from ambient air (air capture) as a means of reducing the global atmospheric CO2 concentration is reviewed. For both conventional CCS from large point sources and air capture, critical research needs are identified and discussed. © Copyright 2011 by Annual Reviews. All rights reserved.

CO 2 Capture from Dilute Gases as a Component of Modern Global Carbon Management

KAUST Repository

Jones, Christopher W.

2011-07-15

The growing atmospheric CO2 concentration and its impact on climate have motivated widespread research and development aimed at slowing or stemming anthropogenic carbon emissions. Technologies for carbon capture and sequestration (CCS) employing mass separating agents that extract and purify CO2 from flue gas emanating from large point sources such as fossil fuel-fired electricity-generating power plants are under development. Recent advances in solvents, adsorbents, and membranes for postcombust- ion CO 2 capture are described here. Specifically, room-temperature ionic liquids, supported amine materials, mixed matrix and facilitated transport membranes, and metal-organic framework materials are highlighted. In addition, the concept of extracting CO2 directly from ambient air (air capture) as a means of reducing the global atmospheric CO2 concentration is reviewed. For both conventional CCS from large point sources and air capture, critical research needs are identified and discussed. © Copyright 2011 by Annual Reviews. All rights reserved.

Scientific Analogies and Their Use in Teaching Science

Science.gov (United States)

Kipnis, Nahum

Analogy in science knew its successes and failures, as illustrated by examples from the eighteenth-century physics. At times, some scientists abstained from using a certain analogy on the ground that it had not yet been demonstrated. Several false discoveries in the 18th and early 19th centuries appeared to support their caution. It is now clear that such a position reflected a methodological confusion that resulted from a failure to distinguish between particular and general analogies. Considering analogy as a hierarchical structure provides a new insight into "testing an analogy". While warning science teachers of dangers associated with use of analogy, historical cases and their analysis provided here may encourage them to use analogy more extensively while avoiding misconceptions. An argument is made that the history of science may be a better guide than philosophy of science and cognitive psychology when it concerns the role of analogy in science and in teaching science for understanding.

99m Tc- la bed somatostatin analogs for imaging somatostatin-receptor-positive tumors

International Nuclear Information System (INIS)

Gandomkar, M.; Najafi, R.; Shafiei, A.; Sadat Ebrahimi, E.; Babaie, M.H.; Rabani, M.

2002-01-01

Over the least few years, 111 In-DTPA- Octreotide has found widespread clinical applicability, especially in oncology. However limitation, especially concerning availability, imaging properties, and costs, remain and have stimulated research on radiolabeling with many alternative radionuclides. The purpose of this investigation was to labeling somatostatin analogs with 99 m Tc and evaluate their suitability as an agents for in vivo use. Octreotide and Tyr-3-Octreotide were labeled by 99 mTc with direct and indirect methods. Sodium ascorbate and sodium dithionite were used for reduction of cystine bridge and HYNIC was used as bifunctional agents and different co ligands used for labeling by 99 mTc. Yield of labeling, purity, stability, internalisation, binding affinity and biodistribution of peptide conjugates were studied. Direct labeling of octreotide was simple, rapid, efficient and yield was good (%60). K d for binding affinity as high (10 -9 ) but stability was low. Labeling for HYNIC-Tyr-Octreotide had a high yield (>%90), good stability, internalisation and biodistribution. with more experimental work and some improve this peptide-based radiopharmaceuticals can be employed in all nuclear medicine centers as a useful agent for imaging of tumors

Drawing Analogies in Environmental Education

Science.gov (United States)

Affifi, Ramsey

2014-01-01

Reconsidering the origin, process, and outcomes of analogy-making suggests practices for environmental educators who strive to disengage humans from the isolating illusions of dichotomizing frameworks. We can view analogies as outcomes of developmental processes within which human subjectivity is but an element, threading our sense of self back…

Cardiotonic agent milrinone stimulates resorption in rodent bone organ culture.

Science.gov (United States)

Krieger, N S; Stappenbeck, T S; Stern, P H

1987-01-01

The cardiotonic agent amrinone inhibits bone resorption in vitro. Milrinone, an amrinone analog, is a more potent cardiotonic agent with lower toxicity. In contrast to amrinone, milrinone stimulated resorption in cultures of neonatal mouse calvaria and fetal rat limb bones. Threshold doses were 0.1 microM in calvaria and 0.1 mM in limb bones; maximal stimulation occurred in calvaria at 0.1 mM. Maximal responses to milrinone and parathyroid hormone were comparable. Milrinone concentrations below 0.1 mM did not affect calvarial cyclic AMP. 0.5 microM indomethacin inhibited milrinone effects in calvaria but usually not in limb bones. 3 nM calcitonin inhibited milrinone-stimulated resorption and there was no escape from this inhibition. Structural homology between milrinone and thyroxine has been reported. We find similarities between milrinone and thyroxine actions on bone, because prostaglandin production was crucial for the effects of both agents in calvaria but not in limb bones, and neither agent exhibited escape from calcitonin inhibition. PMID:3027124

Introducing a logic for real-world agents with degrees of belief

CSIR Research Space (South Africa)

Rens, GB

2009-12-01

Full Text Available stream_source_info Gens_2009.pdf.txt stream_content_type text/plain stream_size 3189 Content-Encoding UTF-8 stream_name Gens_2009.pdf.txt Content-Type text/plain; charset=UTF-8 Introducing a Logic for Real-world Agents... the world could be. A further step to capture uncertain knowledge is to assign a likelihood to each state considered possible so that degrees of belief can be captured. Now as the robot acts and observes while completing its tasks, it will change its...

Conjecturing via Reconceived Classical Analogy

Science.gov (United States)

Lee, Kyeong-Hwa; Sriraman, Bharath

2011-01-01

Analogical reasoning is believed to be an efficient means of problem solving and construction of knowledge during the search for and the analysis of new mathematical objects. However, there is growing concern that despite everyday usage, learners are unable to transfer analogical reasoning to learning situations. This study aims at facilitating…

Agent-Based Modeling for Testing and Designing Novel Decentralized Command and Control System Paradigms

National Research Council Canada - National Science Library

Bonabeau, Eric; Hunt, Carl W; Gaudiano, Paolo

2003-01-01

Agent-based modeling (ABM) is a recent simulation modeling technique that consists of modeling a system from the bottom up, capturing the interactions taking place between the system's constituent units...

Spectrometric analog-to-digital converter

International Nuclear Information System (INIS)

Ormandzhiev, S.I.; Jordanov, V.T.

1988-01-01

Converter of digit-by-digit counterbalancing with slipping dial with number of channels equal to total number of states of the main digital-to-analog converter of digit-by-digit counterbalancing systems is presented. Algorithm for selection of digital-to-analog converters, which must be used by means of computer is suggested

Integrated Sedimentological Approach to Assess Reservoir Quality and Architecture of Khuff Carbonates: Outcrop Analog, Central Saudi Arabia

Science.gov (United States)

Osman, Mutsim; Abdullatif, Osman

2017-04-01

The Permian to Triassic Khuff carbonate reservoirs (and equivalents) in the Middle East are estimated to contain about 38.4% of the world's natural gas reserves. Excellent exposed outcrops in central Saudi Arabia provide good outcrop equivalents to subsurface Khuff reservoirs. This study conduct high resolution outcrop scale investigations on an analog reservoir for upper Khartam of Khuff Formation. The main objective is to reconstruct litho- and chemo- stratigraphic outcrop analog model that may serve to characterize reservoir high resolution (interwell) heterogeneity, continuity and architecture. Given the fact of the limitation of subsurface data and toolsin capturing interwell reservoir heterogeneity, which in turn increases the value of this study.The methods applied integrate sedimentological, stratigraphic petrographic, petrophysical data and chemical analyses for major, trace and rare earth elements. In addition, laser scanning survey (LIDAR) was also utilized in this study. The results of the stratigraphic investigations revealed that the lithofacies range from mudstone, wackestone, packestone and grainstone. These lithofacies represent environments ranging from supratidal, intertidal, subtidal and shoal complex. Several meter-scale and less high resolution sequences and composite sequences within 4th and 5th order cycles were also recognized in the outcrop analog. The lithofacies and architectural analysis revealed several vertically and laterally stacked sequences at the outcrop as revealed from the stratigraphic sections and the lidar scan. Chemostratigraphy is effective in identifying lithofacies and sequences within the outcrop analog. Moreover, different chemical signatures were also recognized and allowed establishing and correlating high resolution lithofacies, reservoir zones, layers and surfaces bounding reservoirs and non-reservoir zones at scale of meters or less. The results of this high resolution outcrop analog study might help to understand

Hydrogen fluoride capture by imidazolium acetate ionic liquid

Science.gov (United States)

Chaban, Vitaly

2015-04-01

Extraction of hydrofluoric acid (HF) from oils is a drastically important problem in petroleum industry, since HF causes quick corrosion of pipe lines and brings severe health problems to humanity. Some ionic liquids (ILs) constitute promising scavenger agents thanks to strong binding to polar compounds and tunability. PM7-MD simulations and hybrid density functional theory are employed here to consider HF capture ability of ILs. Discussing the effects and impacts of the cation and the anion separately and together, we evaluate performance of imidazolium acetate and outline systematic search guidelines for efficient adsorption and extraction of HF.

Relations as transformations: implications for analogical reasoning.

Science.gov (United States)

Leech, Robert; Mareschal, Denis; Cooper, Richard P

2007-07-01

We present two experiments assessing whether the size of a transformation instantiating a relation between two states of the world (e.g., shrinks) is a performance factor affecting analogical reasoning. The first experiment finds evidence of transformation size as a significant factor in adolescent analogical problem solving while the second experiment finds a similar effect on adult analogical reasoning using a markedly different analogical completion paradigm. The results are interpreted as providing evidence for the more general framework that cognitive representations of relations are best understood as mental transformations.

Fermilab accelerator control system: Analog monitoring facilities

International Nuclear Information System (INIS)

Seino, K.; Anderson, L.; Smedinghoff, J.

1987-10-01

Thousands of analog signals are monitored in different areas of the Fermilab accelerator complex. For general purposes, analog signals are sent over coaxial or twinaxial cables with varying lengths, collected at fan-in boxes and digitized with 12 bit multiplexed ADCs. For higher resolution requirements, analog signals are digitized at sources and are serially sent to the control system. This paper surveys ADC subsystems that are used with the accelerator control systems and discusses practical problems and solutions, and it describes how analog data are presented on the console system

Amino acid salt solutions as solvents in CO2 capture from flue gas

DEFF Research Database (Denmark)

Lerche, Benedicte Mai; Thomsen, Kaj; Stenby, Erling Halfdan

New solvents based on the salts of amino acids have emerged as an alternative to the alkanolamine solutions, for the chemical absorption of CO2 from flue gas. But only few studies on amino acids as CO2 capturing agents have been performed so far. One of the interesting features of amino acid salt...... solutions is their ability to form solid precipitates upon the absorption of CO2. The occurrence of crystallization offers the possibility of increasing the CO2 loading capacity of the solvent. However, precipitation can also have negative effect on the CO2 capture process. The chemical nature of the solid...... of glycine, taurine, and lysine, while in the case of proline, and glutamic acid, the precipitate was found to be bicarbonate. These results give an important contribution to further understanding the potential of amino acid salt solutions in CO2 capture from flue gas....

Ultrastructural changes in tumor cells following boron neutron capture therapy

International Nuclear Information System (INIS)

Barkla, D.H.; Brown, J.K.; Meriaty, H.; Allen, B.J.

1992-01-01

In a previous study the authors reported on morphological changes in two human melanoma cell lines treated with 10 B-phenylalanine(BPA) and Boron Neutron Capture Therapy(BNCT). The present study describes morphological changes in melanoma and glioma cell lines treated with boron-tetraphenyl porphyrin(BTPP) and BNCT. Porphyrin compounds are selectively taken up by tumor cells and have been used clinically in phototherapy treatment of cancer patients. Boronated porphyrins show good potential as therapeutic agents in BNCT treatment of human cancer patients

Musik som analogi og metafor

DEFF Research Database (Denmark)

Bonde, Lars Ole

2014-01-01

Indeholder underkapitlerne: 2.5.1 Musik som analogi 2.5.2 Musik som metafor 2.5.3 Musikkens psykologiske funktioner - en taxonomi og metaforisk lytning til fire baroksatser......Indeholder underkapitlerne: 2.5.1 Musik som analogi 2.5.2 Musik som metafor 2.5.3 Musikkens psykologiske funktioner - en taxonomi og metaforisk lytning til fire baroksatser...

Percolation and cooperation with mobile agents: geometric and strategy clusters.

Science.gov (United States)

Vainstein, Mendeli H; Brito, Carolina; Arenzon, Jeferson J

2014-08-01

We study the conditions for persistent cooperation in an off-lattice model of mobile agents playing the Prisoner's Dilemma game with pure, unconditional strategies. Each agent has an exclusion radius r(P), which accounts for the population viscosity, and an interaction radius r(int), which defines the instantaneous contact network for the game dynamics. We show that, differently from the r(P)=0 case, the model with finite-sized agents presents a coexistence phase with both cooperators and defectors, besides the two absorbing phases, in which either cooperators or defectors dominate. We provide, in addition, a geometric interpretation of the transitions between phases. In analogy with lattice models, the geometric percolation of the contact network (i.e., irrespective of the strategy) enhances cooperation. More importantly, we show that the percolation of defectors is an essential condition for their survival. Differently from compact clusters of cooperators, isolated groups of defectors will eventually become extinct if not percolating, independently of their size.

Military Importance of Natural Toxins and Their Analogs

Directory of Open Access Journals (Sweden)

Vladimír Pitschmann

2016-04-01

Full Text Available Toxin weapon research, development, production and the ban on its uses is an integral part of international law, with particular attention paid to the protection against these weapons. In spite of this, hazards associated with toxins cannot be completely excluded. Some of these hazards are also pointed out in the present review. The article deals with the characteristics and properties of natural toxins and synthetic analogs potentially constituting the basis of toxin weapons. It briefly describes the history of military research and the use of toxins from distant history up to the present age. With respect to effective disarmament conventions, it mentions certain contemporary concepts of possible toxin applications for military purposes and the protection of public order (suppression of riots; it also briefly refers to the question of terrorism. In addition, it deals with certain traditional as well as modern technologies of the research, synthesis, and use of toxins, which can affect the continuing development of toxin weapons. These are, for example, cases of new toxins from natural sources, their chemical synthesis, production of synthetic analogs, the possibility of using methods of genetic engineering and modern biotechnologies or the possible applications of nanotechnology and certain pharmaceutical methods for the effective transfer of toxins into the organism. The authors evaluate the military importance of toxins based on their comparison with traditional chemical warfare agents. They appeal to the ethics of the scientific work as a principal condition for the prevention of toxin abuse in wars, military conflicts, as well as in non-military attacks.

Military Importance of Natural Toxins and Their Analogs.

Science.gov (United States)

Pitschmann, Vladimír; Hon, Zdeněk

2016-04-28

Toxin weapon research, development, production and the ban on its uses is an integral part of international law, with particular attention paid to the protection against these weapons. In spite of this, hazards associated with toxins cannot be completely excluded. Some of these hazards are also pointed out in the present review. The article deals with the characteristics and properties of natural toxins and synthetic analogs potentially constituting the basis of toxin weapons. It briefly describes the history of military research and the use of toxins from distant history up to the present age. With respect to effective disarmament conventions, it mentions certain contemporary concepts of possible toxin applications for military purposes and the protection of public order (suppression of riots); it also briefly refers to the question of terrorism. In addition, it deals with certain traditional as well as modern technologies of the research, synthesis, and use of toxins, which can affect the continuing development of toxin weapons. These are, for example, cases of new toxins from natural sources, their chemical synthesis, production of synthetic analogs, the possibility of using methods of genetic engineering and modern biotechnologies or the possible applications of nanotechnology and certain pharmaceutical methods for the effective transfer of toxins into the organism. The authors evaluate the military importance of toxins based on their comparison with traditional chemical warfare agents. They appeal to the ethics of the scientific work as a principal condition for the prevention of toxin abuse in wars, military conflicts, as well as in non-military attacks.

Non-analog Monte Carlo estimators for radiation momentum deposition

International Nuclear Information System (INIS)

Hykes, Joshua M.; Densmore, Jeffery D.

2009-01-01

The standard method for calculating radiation momentum deposition in Monte Carlo simulations is the analog estimator, which tallies the change in a particle's momentum at each interaction with the matter. Unfortunately, the analog estimator can suffer from large amounts of statistical error. In this paper, we present three new non-analog techniques for estimating momentum deposition. Specifically, we use absorption, collision, and track-length estimators to evaluate a simple integral expression for momentum deposition that does not contain terms that can cause large amounts of statistical error in the analog scheme. We compare our new non-analog estimators to the analog estimator with a set of test problems that encompass a wide range of material properties and both isotropic and anisotropic scattering. In nearly all cases, the new non-analog estimators outperform the analog estimator. The track-length estimator consistently yields the highest performance gains, improving upon the analog-estimator figure of merit by factors of up to two orders of magnitude.

Intelligent judgements over health risks in a spatial agent-based model.

Science.gov (United States)

Abdulkareem, Shaheen A; Augustijn, Ellen-Wien; Mustafa, Yaseen T; Filatova, Tatiana

2018-03-20

Millions of people worldwide are exposed to deadly infectious diseases on a regular basis. Breaking news of the Zika outbreak for instance, made it to the main media titles internationally. Perceiving disease risks motivate people to adapt their behavior toward a safer and more protective lifestyle. Computational science is instrumental in exploring patterns of disease spread emerging from many individual decisions and interactions among agents and their environment by means of agent-based models. Yet, current disease models rarely consider simulating dynamics in risk perception and its impact on the adaptive protective behavior. Social sciences offer insights into individual risk perception and corresponding protective actions, while machine learning provides algorithms and methods to capture these learning processes. This article presents an innovative approach to extend agent-based disease models by capturing behavioral aspects of decision-making in a risky context using machine learning techniques. We illustrate it with a case of cholera in Kumasi, Ghana, accounting for spatial and social risk factors that affect intelligent behavior and corresponding disease incidents. The results of computational experiments comparing intelligent with zero-intelligent representations of agents in a spatial disease agent-based model are discussed. We present a spatial disease agent-based model (ABM) with agents' behavior grounded in Protection Motivation Theory. Spatial and temporal patterns of disease diffusion among zero-intelligent agents are compared to those produced by a population of intelligent agents. Two Bayesian Networks (BNs) designed and coded using R and are further integrated with the NetLogo-based Cholera ABM. The first is a one-tier BN1 (only risk perception), the second is a two-tier BN2 (risk and coping behavior). We run three experiments (zero-intelligent agents, BN1 intelligence and BN2 intelligence) and report the results per experiment in terms of

Evaluation of carboranylporphyrins as boron delivery agents for neutron capture therapy

International Nuclear Information System (INIS)

Kawabata, Shinji; Barth, Rolf F.; Yang, Weilian; Wu, Gong; Binns, Peter J.; Riley, Kent J.; Ongayi, Owendi; Gottumukkala, Vijay; Vicente, Graca H.

2006-01-01

The goals of the present study were two-fold. First, to determine the biodistribution of three carboranyl-porphyrins, designated H 2 DCP, H 2 TCP and H 2 TBP following intracerebral (i.c.) administration by means of convection enhanced delivery (CED) to F98 glioma bearing rats. Tumor boron concentrations immediately after CED were 36 and 88 μg/g for H 2 DCP and H 2 TCP, respectively, and were 103 and 62 μg/g for H 2 TCP and H 2 TBP, respectively, 24h after termination of CED. The corresponding normal brain concentrations were 5.2, 3.3 and 0.8 μg/g, and blood and liver concentrations all were 2 TCP and H 2 TBP as boron delivery agents in F98 glioma bearing rats. BNCT was carried out at the Massachusetts Institute of Technology (MIT) Research Reactor (MITRR) 24 h after CED of 200 μl of either 0.5 mg of H 2 TCP or H 2 TBP. Untreated control rats all died within 29 days after tumor implantation and had a mean survival time (MST) of 23±3 days and irradiated controls had a MST of 27±3 days. Animals that received H 2 TCP by CED, followed by BNCT, had a MST of 35±4 days and animals received H 2 TBP had a MST of 44±10 days. Further studies were carried out using H 2 TBP at a dose of 0.2 mg administered by a Harvard pump, either alone or in combination with i.v. BPA, and the corresponding MSTs were 34±3 d and 43±9 d, respectively. Histopathologic examination of the brains of animals that died revealed large numbers of porphyrin laden macrophages and extracellular accumulations of free porphyrin indicating that tumor cell uptake was suboptimal. Further studies are planned to synthesize and evaluate new compounds that will have enhanced cellular uptake and efficacy as boron delivery agents for NCT. (author)

The Role of Implicit Motives in Strategic Decision-Making: Computational Models of Motivated Learning and the Evolution of Motivated Agents

Directory of Open Access Journals (Sweden)

Kathryn Merrick

2015-11-01

Full Text Available Individual behavioral differences in humans have been linked to measurable differences in their mental activities, including differences in their implicit motives. In humans, individual differences in the strength of motives such as power, achievement and affiliation have been shown to have a significant impact on behavior in social dilemma games and during other kinds of strategic interactions. This paper presents agent-based computational models of power-, achievement- and affiliation-motivated individuals engaged in game-play. The first model captures learning by motivated agents during strategic interactions. The second model captures the evolution of a society of motivated agents. It is demonstrated that misperception, when it is a result of motivation, causes agents with different motives to play a given game differently. When motivated agents who misperceive a game are present in a population, higher explicit payoff can result for the population as a whole. The implications of these results are discussed, both for modeling human behavior and for designing artificial agents with certain salient behavioral characteristics.

Analog-to-digital conversion using custom CMOS analog memory for the EOS time projection chamber

International Nuclear Information System (INIS)

Lee, K.L.; Arthur, A.A.; Jones, R.W.; Matis, H.S.; Nakamura, M.; Kleinfelder, S.A.; Ritter, H.G.; Wienman, H.H.

1990-01-01

This paper describes the multiplexing scheme of custom CMOS analog memory integrated circuits, 16 channels x 256 cells, into analog to digital converters (ADC's) to handle 15,360 signal channels of a time projection, chamber detector system. Primary requirements of this system are high density, low power and large dynamic range. The analog memory device multiplexing scheme was designed to digitize the information stored in the memory cells. The digitization time of the ADC's and the settling times for the memory unit were carefully interleaved to optimize the performance and timing during the multiplexing operation. This kept the total number of ADC's, a costly and power dissipative component, to an acceptable minimum

A Distributed Framework for Real Time Path Planning in Practical Multi-agent Systems

KAUST Repository

Abdelkader, Mohamed; Jaleel, Hassan; Shamma, Jeff S.

2017-01-01

We present a framework for distributed, energy efficient, and real time implementable algorithms for path planning in multi-agent systems. The proposed framework is presented in the context of a motivating example of capture the flag which

CASCADE: An Agent Based Framework For Modeling The Dynamics Of Smart Electricity Systems

OpenAIRE

Rylatt, R. M.; Gammon, Rupert; Boait, Peter John; Varga, L.; Allen, P.; Savill, M.; Snape, J. Richard; Lemon, Mark; Ardestani, B. M.; Pakka, V. H.; Fletcher, G.; Smith, S.; Fan, D.; Strathern, M.

2013-01-01

Collaborative project with Cranfield University The Complex Adaptive Systems, Cognitive Agents and Distributed Energy (CASCADE) project is developing a framework based on Agent Based Modelling (ABM). The CASCADE Framework can be used both to gain policy and industry relevant insights into the smart grid concept itself and as a platform to design and test distributed ICT solutions for smart grid based business entities. ABM is used to capture the behaviors of diff erent socia...

Phase I/II Trial of Epothilone Analog BMS-247550, Mitoxantrone, and Prednisone in HRPC Patients Previously Treated with Chemotherapy

Science.gov (United States)

2006-07-01

Tomasz Beer , M.D. Kathleen Beekman, M.D. Associate Professor of Medicine Lecturer, Internal Medicine and Urology OHSU Cancer Institute University of... fermentation of the myxobacteria Sorangium cellulosum.(10) The chief components of the fermentation process are epothilones A and B. In 1994, the National...ixabepilone) is a semi-synthetic analog of the natural product epothilone B, a non-taxane tubulin polymerization agent obtained by fermentation of the

Myocardial imaging with a radioiodinated norepinephrine storage analog

International Nuclear Information System (INIS)

Wieland, D.M.; Brown, L.E.; Rogers, W.L.; Worthington, K.C.; Wu, J.L.; Clinthorne, N.H.; Otto, C.A.; Swanson, D.P.; Beierwaltes, W.H.

1981-01-01

Meta-iodobenzylguanidine (M-IBG), an iodinated aromatic analog of the hypotensive drug guanethidine, localizes in the heart of the rat, dog, and rhesus monkey. A comparative study of tissue distribution in the dog has been performed with five myocardiophilic agents: thallium-201, I-125 16-iodohexadecanoic acid, H-3 norepinephrine, C-14 guanethidine and I-125 M-IBG. The last two compounds give heart concentrations and heart-to-blood concentration ratios similar to those of thallium-201. Planar and tomographic images of the hearts of the dog and rhesus monkey were obtained using I-131 or I-123 labeled M-IBG. Blocking studies with reserpine suggest that a major component of myocardial retention of M-IBG is sequestration within the norepinephrine storage vesicles of the adrenergic nerves. The localization of M-IBG in other organs with rich sympathetic innervation and the relative insensitivity of myocardial uptake to a wide range of loading doses lend additional support for a neuronal mode of retention

NASA HRP Immunology Discipline - Use of Terrestrial Analogs

Science.gov (United States)

Crucian, Brian

2014-01-01

Due to the cost and operational constraints, as well as technical implementation limitations, it is desirous to perform relevant space physiology investigations first in terrestrial 'space analogs'. This is particularly true for initial investigations, which may then provide appropriate focus for subsequent flight investigations, or for mechanistic investigations that simply cannot be performed during spaceflight. Appropriate analog choice is extremely important. There are a wide variety of terrestrial space analogs, each relevant to a particular physiological discipline (or disciplines) and each with a particular fidelity (or lack thereof) to spaceflight, and each with unique operational constraints. The HRP Immunology Discipline is tasked with managing the HRP Risk concerning clinical risk for Astronaut crews related to spaceflight-associated immune dysregulation. Such dysregulation has been documented to occur during spaceflight, and found to persist for the duration of a 6-month ISS mission. Studies continue to characterize the onorbit phenomenon, but it generally consists of diminished immunocyte function, dysregulated cytokine profiles, and persistent herpesvirus reactivation. Causes are thought to synergistically include microgravity, psychological or physiological stress, radiation, and/or circadian misalignment. An appropriate terrestrial analog for immune dysregulation would replicate as many of these influences as possible. Such analogs may include clinostat or bioreactor cell culture (microgravity), hindlimb suspension (stress, fluid shifts, hypokinesis), or human deployment to remote or extreme environments (isolation, stress, circadian). Also, the laboratory setting may be used as an analog, or to augment analogs, such as sleep deprivation/misalignment or human centrifugation to replicate gravitational stress. As an appropriate example of a NASA Disciplines use of Terrestrial space analogs, this talk will discuss spaceflight associated immune

The Development of Analogical Reasoning Processes.

Science.gov (United States)

Sternberg, Robert J.; Rifkin, Bathsheva

1979-01-01

Two experiments were conducted to test the generalizability to children of a theory of analogical reasoning processes, originally proposed for adults, and to examine the development of analogical reasoning processes in terms of five proposed sources of cognitive development. (MP)

Computational approaches to analogical reasoning current trends

CERN Document Server

Richard, Gilles

2014-01-01

Analogical reasoning is known as a powerful mode for drawing plausible conclusions and solving problems. It has been the topic of a huge number of works by philosophers, anthropologists, linguists, psychologists, and computer scientists. As such, it has been early studied in artificial intelligence, with a particular renewal of interest in the last decade. The present volume provides a structured view of current research trends on computational approaches to analogical reasoning. It starts with an overview of the field, with an extensive bibliography. The 14 collected contributions cover a large scope of issues. First, the use of analogical proportions and analogies is explained and discussed in various natural language processing problems, as well as in automated deduction. Then, different formal frameworks for handling analogies are presented, dealing with case-based reasoning, heuristic-driven theory projection, commonsense reasoning about incomplete rule bases, logical proportions induced by similarity an...

Neutron dosimetry in boron neutron capture therapy

International Nuclear Information System (INIS)

Fairchild, R.G.; Miola, U.J.; Ettinger, K.V.

1981-01-01

The recent development of various borated compounds and the utilization of one of these (Na 2 B 12 H 11 SH) to treat brain tumors in clinical studies in Japan has renewed interest in neutron capture therapy. In these procedures thermal neutrons interact with 10 B in boron containing cells through the 10 B(n,α) 7 Li reaction producing charged particles with a maximum range of approx. 10μm in tissue. Borated analogs of chlorpromazine, porphyrin, thiouracil and deoxyuridine promise improved tumor uptake and blood clearance. The therapy beam from the Medical Research Reactor in Brookhaven contains neutrons from a modified and filtered fission spectrum and dosimetric consequences of the use of the above mentioned compounds in conjunction with thermal and epithermal fluxes are discussed in the paper. One of the important problems of radiation dosimetry in capture therapy is determination of the flux profile and, hence, the dose profile in the brain. This has been achieved by constructing a brain phantom made of TE plastic. The lyoluminescence technique provides a convenient way of monitoring the neutron flux distributions; the detectors for this purpose utilize 6 Li and 10 B compounds. Such compounds have been synthesized specially for the purpose of dosimetry of thermal and epithermal beams. In addition, standard lyoluminescent phosphors, like glutamine, could be used to determine the collisional component of the dose as well as the contribution of the 14 N(n,p) 14 C reaction. Measurements of thermal flux were compared with calculations and with measurements done with activation foils

Design and Analysis of Reconfigurable Analog System

Science.gov (United States)

2011-02-01

34010010" �" �" �" �" �" �" �±" N3 N2 N± P1 P2 P3 * Current sources $RR = 1; *Ramp Rate (slope of the...2008/12/12/31e83bac-500f-4182- acca -4d360295fd9c.pdf, Analog Devices, Analog Dialogue 39-06, June 2005. [15] D. A. Johns, K. Martin "Analog Integrated

Inhibition of the Escherichia coli 6-oxopurine phosphoribosyltransferases by nucleoside phosphonates: potential for new antibacterial agents

Czech Academy of Sciences Publication Activity Database

Keough, D. T.; Hocková, Dana; Rejman, Dominik; Špaček, Petr; Vrbková, Silvie; Krečmerová, Marcela; Eng, W. S.; Jans, H.; West, N. P.; Naesens, L. M. J.; de Jersey, J.; Guddat, L. W.

2013-01-01

Roč. 56, č. 17 (2013), s. 6967-6984 ISSN 0022-2623 R&D Projects: GA ČR GAP207/11/0108 Institutional support: RVO:61388963 Keywords : nucleoside phosphonates * antibacterial agents * hypoxanthine-guanine phosphoribosyltransferase * state analog inhibitor * antimalarial chemotherapy Subject RIV: CC - Organic Chemistry Impact factor: 5.480, year: 2013

Perceptions of Rebuttal Analogy: Politeness and Implications for Persuasion.

Science.gov (United States)

Whaley, Bryan B.

1997-01-01

States that recent theorizing about the role of analogy in persuasion suggests that "rebuttal" analogy addresses two communicative functions by serving as argument and a method of social attack. Examines message receivers' perceptions of rebuttal analogy and rebuttal analogy users. Finds that participants perceived the communicator using…

Elucidating the neurotoxic effects of MDMA and its analogs.

Science.gov (United States)

Karuppagounder, Senthilkumar S; Bhattacharya, Dwipayan; Ahuja, Manuj; Suppiramaniam, Vishnu; Deruiter, Jack; Clark, Randall; Dhanasekaran, Muralikrishnan

2014-04-17

There is a rapid increase in the use of methylenedioxymethamphetamine (MDMA) and its structural congeners/analogs globally. MDMA and MDMA-analogs have been synthesized illegally in furtive dwellings and are abused due to its addictive potential. Furthermore, MDMA and MDMA-analogs have shown to have induced several adverse effects. Hence, understanding the mechanisms mediating this neurotoxic insult of MDMA-analogs is of immense importance for the public health in the world. We synthesized and investigated the neurotoxic effects of MDMA and its analogs [4-methylenedioxyamphetamine (MDA), 2, 6-methylenedioxyamphetamine (MDMA), and N-ethyl-3, 4-methylenedioxyamphetamine (MDEA)]. The stimulatory or the dopaminergic agonist effects of MDMA and MDMA-analogs were elucidated using the established 6-hydroxydopamine lesioned animal model. Additionally, we also investigated the neurotoxic mechanisms of MDMA and MDMA-analogs on mitochondrial complex-I activity and reactive oxygen species generation. MDMA and MDMA-analogs exhibited stimulatory activity as compared to amphetamines and also induced several behavioral changes in the rodents. MDMA and MDMA-analogs enhanced the reactive oxygen generation and inhibited mitochondrial complex-I activity which can lead to neurodegeneration. Hence the mechanism of neurotoxicity, MDMA and MDMA-analogs can enhance the release of monoamines, alter the monoaminergic neurotransmission, and augment oxidative stress and mitochondrial abnormalities leading to neurotoxicity. Thus, our study will help in developing effective pharmacological and therapeutic approaches for the treatment of MDMA and MDMA-analog abuse. Copyright © 2014 Elsevier Inc. All rights reserved.

A stochastic multi-agent optimization model for energy infrastructure planning under uncertainty and competition.

Science.gov (United States)

2017-07-04

This paper presents a stochastic multi-agent optimization model that supports energy infrastruc- : ture planning under uncertainty. The interdependence between dierent decision entities in the : system is captured in an energy supply chain network, w...

Optional carbon capture

Energy Technology Data Exchange (ETDEWEB)

Alderson, T.; Scott, S.; Griffiths, J. [Jacobs Engineering, London (United Kingdom)

2007-07-01

In the case of IGCC power plants, carbon capture can be carried out before combustion. The carbon monoxide in the syngas is catalytically shifted to carbon dioxide and then captured in a standard gas absorption system. However, the insertion of a shift converter into an existing IGCC plant with no shift would mean a near total rebuild of the gasification waste heat recovery, gas treatment system and HRSG, with only the gasifier and gas turbine retaining most of their original features. To reduce the extent, cost and time taken for the revamping, the original plant could incorporate the shift, and the plant would then be operated without capture to advantage, and converted to capture mode of operation when commercially appropriate. This paper examines this concept of placing a shift converter into an IGCC plant before capture is required, and operating the same plant first without and then later with CO{sub 2} capture in a European context. The advantages and disadvantages of this 'capture ready' option are discussed. 6 refs., 2 figs., 4 tabs.

Using an agent-based model to analyze the dynamic communication network of the immune response

Directory of Open Access Journals (Sweden)

Doolittle John

2011-01-01

Full Text Available Abstract Background The immune system behaves like a complex, dynamic network with interacting elements including leukocytes, cytokines, and chemokines. While the immune system is broadly distributed, leukocytes must communicate effectively to respond to a pathological challenge. The Basic Immune Simulator 2010 contains agents representing leukocytes and tissue cells, signals representing cytokines, chemokines, and pathogens, and virtual spaces representing organ tissue, lymphoid tissue, and blood. Agents interact dynamically in the compartments in response to infection of the virtual tissue. Agent behavior is imposed by logical rules derived from the scientific literature. The model captured the agent-to-agent contact history, and from this the network topology and the interactions resulting in successful versus failed viral clearance were identified. This model served to integrate existing knowledge and allowed us to examine the immune response from a novel perspective directed at exploiting complex dynamics, ultimately for the design of therapeutic interventions. Results Analyzing the evolution of agent-agent interactions at incremental time points from identical initial conditions revealed novel features of immune communication associated with successful and failed outcomes. There were fewer contacts between agents for simulations ending in viral elimination (win versus persistent infection (loss, due to the removal of infected agents. However, early cellular interactions preceded successful clearance of infection. Specifically, more Dendritic Agent interactions with TCell and BCell Agents, and more BCell Agent interactions with TCell Agents early in the simulation were associated with the immune win outcome. The Dendritic Agents greatly influenced the outcome, confirming them as hub agents of the immune network. In addition, unexpectedly high frequencies of Dendritic Agent-self interactions occurred in the lymphoid compartment late in the

Learning Plate Tectonics Using a Pre-Analogy Step

Science.gov (United States)

Glesener, G. B.; Sandoval, W. A.

2011-12-01

Previous research has shown that children tend to demonstrate lower performance on analogical reasoning tasks at a causal relations level compared to most adults (Gentner & Toupin, 1986). This tendency is an obstacle that geoscience educators must overcome because of the high frequency of analogies used in geoscience pedagogy. In particular, analog models are used to convey complex systems of non-everyday/non-observable events found in nature, such as plate tectonics. Key factors in successful analogical reasoning that have been suggested by researchers include knowledge of the causal relations in the base analog (Brown & Kane, 1988; Gentner, 1988; Gentner & Toupin, 1986), and development of learning strategies and metaconceptual competence(Brown & Kane, 1988). External factors, such as guiding cues and hints have been useful cognitive supports that help students reason through analogical problems (Gick & Holyoak, 1980). Cognitive supports have been seen by researchers to decrease processing demands on retrieval and working memory (Richland, Zur, & Holyoak, 2007). We observed third and fourth graders learning about plate tectonics beginning with a pre-analogy step-a cognitive support activity a student can do before working with an analogy to understand the target. This activity was designed to aid students in developing their understanding of object attributes and relations within an analog model so that more focus can be placed on mapping the corresponding higher-order relations between the base and target. Students learned targeted concepts of plate tectonics, as measured by pre to post gains on items adapted from the Geosciences Concept Inventory. Analyses of classroom interaction showed that students used the object attributes and higher-order relations highlighted in the pre-analogy activity as resources to reason about plate boundaries and plate movement during earthquakes.

Natural analogs for Yucca Mountain

International Nuclear Information System (INIS)

Murphy, W.M.

1995-01-01

High-level radioactive waste in the US, spent fuels from commercial reactors and nuclear materials generated by defense activities, will remain potentially hazardous for thousands of years. Demonstrable long-term stability of certain geologic and geochemical systems motivates and sustains the concept that high-level waste can be safely isolated in geologic repositories for requisite periods of time. Each geologic repository is unique in its properties and performance with reguard to isolation of nuclear wastes. Studies of processes analogous to waste-form alteration and radioelement transport in environments analogous to Yucca Mountain are being conducted at two sites, described in this article to illustrate uses of natural analog data: the Nopal I uranium deposit in the Sierra Pena Blanca, Mexico, and the Akrotiri archaeological site on the island of Santorini, Greece

LL-37-derived short antimicrobial peptide KR-12-a5 and its d-amino acid substituted analogs with cell selectivity, anti-biofilm activity, synergistic effect with conventional antibiotics, and anti-inflammatory activity.

Science.gov (United States)

Kim, Eun Young; Rajasekaran, Ganesan; Shin, Song Yub

2017-08-18

KR-12-a5 is a 12-meric α-helical antimicrobial peptide (AMP) with dual antimicrobial and anti-inflammatory activities designed from human cathelicidin LL-37. We designed and synthesized a series of d-amino acid-substituted analogs of KR-12-a5 with the aim of developing novel α-helical AMPs that possess higher cell selectivity than KR-12-a5, while maintaining the anti-inflammatory activity. d-amino acid incorporation into KR-12-a5 induced a significant improvement in the cell selectivity by 2.6- to 13.6-fold as compared to KR-12-a5, while maintaining the anti-inflammatory activity. Among the three analogs, KR-12-a5 (6- D L) with d-amino acid in the polar-nonpolar interface (Leu 6 ) showed the highest cell selectivity (therapeutic index: 61.2). Similar to LL-37, KR-12-a5 and its analogs significantly inhibited the expression and secretion of NO, TNF-α, IL-6 and MCP-1 from LPS-stimulated RAW264.7 cells. KR-12-a5 and its analogs showed a more potent antimicrobial activity against antibiotic-resistant bacteria, including clinically isolated MRSA, MDRPA, and VREF than LL-37 and melittin. Furthermore, compared to LL-37, KR-12-a5 and its analogs showed greater synergistic effects with conventional antibiotics, such as chloramphenicol, ciprofloxacin, and oxacillin against MDRPA; KR-12-a5 and its analogs had a FICI range between 0.25 and 0.5, and LL-37 had a range between 0.75 and 1.5. KR-12-a5 and its analogs were found to be more effective anti-biofilm agents against MDRPA than LL-37. In addition, KR-12-a5 and its analogs maintained antimicrobial activity in physiological salts and human serum. SYTOX Green uptake and membrane depolarization studies revealed that KR-12-a5 and its analogs kills microbial cells by permeabilizing the cell membrane and damaging membrane integrity. Taken together, our results suggest that KR-12-a5 and its analogs can be developed further as novel antimicrobial/anti-inflammatory agents to treat antibiotic-resistant infections. Copyright �

Simulating classroom lessons : an agent-based attempt

OpenAIRE

Ingram, Fred; Brooks, Roger John

2018-01-01

This is an interim report on a project to construct an agent-based simulation that reproduces some of the interactions between students and their teacher in classroom lessons. In a pilot study, the activities of 67 students and 7 teachers during 40 lessons were recorded using a data collection instrument that currently captures 17 student states and 15 teacher states. These data enabled various conceptual models to be explored, providing empirical values and distributions for the model parame...

Adaptive capture of expert knowledge

Energy Technology Data Exchange (ETDEWEB)

Barrett, C.L.; Jones, R.D. [Los Alamos National Lab., NM (United States); Hand, Un Kyong [Los Alamos National Lab., NM (United States)]|[US Navy (United States)

1995-05-01

A method is introduced that can directly acquire knowledge-engineered, rule-based logic in an adaptive network. This adaptive representation of the rule system can then replace the rule system in simulated intelligent agents and thereby permit further performance-based adaptation of the rule system. The approach described provides both weight-fitting network adaptation and potentially powerful rule mutation and selection mechanisms. Nonlinear terms are generated implicitly in the mutation process through the emergent interaction of multiple linear terms. By this method it is possible to acquire nonlinear relations that exist in the training data without addition of hidden layers or imposition of explicit nonlinear terms in the network. We smoothed and captured a set of expert rules with an adaptive network. The motivation for this was to (1) realize a speed advantage over traditional rule-based simulations; (2) have variability in the intelligent objects not possible by rule-based systems but provided by adaptive systems: and (3) maintain the understandability of rule-based simulations. A set of binary rules was smoothed and converted into a simple set of arithmetic statements, where continuous, non-binary rules are permitted. A neural network, called the expert network, was developed to capture this rule set, which it was able to do with zero error. The expert network is also capable of learning a nonmonotonic term without a hidden layer. The trained network in feedforward operation is fast running, compact, and traceable to the rule base.

Analogy-Enhanced Instruction: Effects on Reasoning Skills in Science

Science.gov (United States)

Remigio, Krisette B.; Yangco, Rosanelia T.; Espinosa, Allen A.

2014-01-01

The study examined the reasoning skills of first year high school students after learning general science concepts through analogies. Two intact heterogeneous sections were randomly assigned to Analogy-Enhanced Instruction (AEI) group and Non Analogy-Enhanced (NAEI) group. Various analogies were incorporated in the lessons of the AEI group for…

Gravitational capture

International Nuclear Information System (INIS)

Bondi, H.

1979-01-01

In spite of the strength of gravitational focres between celestial bodies, gravitational capture is not a simple concept. The principles of conservation of linear momentum and of conservation of angular momentum, always impose severe constraints, while conservation of energy and the vital distinction between dissipative and non-dissipative systems allows one to rule out capture in a wide variety of cases. In complex systems especially those without dissipation, long dwell time is a more significant concept than permanent capture. (author)

Novel Exenatide Analogs with Peptidic Albumin Binding Domains: Potent Anti-Diabetic Agents with Extended Duration of Action

Science.gov (United States)

Levy, Odile E.; Jodka, Carolyn M.; Ren, Shijun Steven; Mamedova, Lala; Sharma, Abhinandini; Samant, Manoj; D’Souza, Lawrence J.; Soares, Christopher J.; Yuskin, Diane R.; Jin, Li Jenny; Parkes, David G.; Tatarkiewicz, Krystyna; Ghosh, Soumitra S.

2014-01-01

The design, synthesis and pharmacology of novel long-acting exenatide analogs for the treatment of metabolic diseases are described. These molecules display enhanced pharmacokinetic profile and potent glucoregulatory and weight lowering actions compared to native exenatide. [Leu14]exenatide-ABD is an 88 residue peptide amide incorporating an Albumin Binding Domain (ABD) scaffold. [Leu14]exenatide-ABP is a 53 residue peptide incorporating a short Albumin Binding Peptide (ABP). [Leu14]exenatide-ABD and [Leu14]exenatide-ABP exhibited nanomolar functional GLP-1 receptor potency and were metabolically stable in vitro in human plasma and in a pancreatic digestive enzyme mixture. Both molecules displayed picomolar and nanomolar binding association with albumin across multiple species and circulating half lives of 16 and 11 hours, respectively, post a single IV dose in rats. Unlike exenatide, both molecules elicited robust glucose lowering when injected 1 day prior to an oral glucose tolerance test, indicative of their extended duration of action. [Leu14]exenatide-ABD was compared to exenatide in a Lep ob/ob mouse model of diabetes. Twice-weekly subcutaneously dosed [Leu14]exenatide-ABD displayed superior glucose lowering and weight loss in diabetic mice when compared to continuously infused exenatide at the same total weekly dose. A single oral administration of each molecule via an enteric coated capsule to cynomolgus monkeys showed superior pharmacokinetics for [Leu14]exenatide-ABD as compared to [Leu14]exenatide-ABP with detectable exposure longer than 14 days. These studies support the potential use of these novel long acting exenatide analogs with different routes of administration for the treatment of type 2 diabetes. PMID:24503632

Epistemology of analogy: Knowledge, society and expression

Directory of Open Access Journals (Sweden)

Mauricio Beuchot

2017-06-01

Full Text Available In this article we expose the bases of analog epistemology. This theory of knowledge is between an extreme subjectivism and an extreme objectivism. Analog hermeneutics is a realistic hermeneutics. She seeks the truth, but incorporates the meaning and emotion. We have separated the reason from the experience, the praxis theory, the mind or the soul of the body. We have to get them back together, if we do not get lost in the rational (which says little of the human being, or we lose ourselves in the emotional (without logical consistency. The analogical hermeneutic realism is able, thanks to the analogy itself, to mediate in this way of union.

Capture ready study

Energy Technology Data Exchange (ETDEWEB)

Minchener, A.

2007-07-15

There are a large number of ways in which the capture of carbon as carbon dioxide (CO{sub 2}) can be integrated into fossil fuel power stations, most being applicable for both gas and coal feedstocks. To add to the choice of technology is the question of whether an existing plant should be retrofitted for capture, or whether it is more attractive to build totally new. This miscellany of choices adds considerably to the commercial risk of investing in a large power station. An intermediate stage between the non-capture and full capture state would be advantageous in helping to determine the best way forward and hence reduce those risks. In recent years the term 'carbon capture ready' or 'capture ready' has been coined to describe such an intermediate stage plant and is now widely used. However a detailed and all-encompassing definition of this term has never been published. All fossil fuel consuming plant produce a carbon dioxide gas byproduct. There is a possibility of scrubbing it with an appropriate CO{sub 2} solvent. Hence it could be said that all fossil fuel plant is in a condition for removal of its CO{sub 2} effluent and therefore already in a 'capture ready' state. Evidently, the practical reality of solvent scrubbing could cost more than the rewards offered by such as the ETS (European Trading Scheme). In which case, it can be said that although the possibility exists of capturing CO{sub 2}, it is not a commercially viable option and therefore the plant could not be described as ready for CO{sub 2} capture. The boundary between a capture ready and a non-capture ready condition using this definition cannot be determined in an objective and therefore universally acceptable way and criteria must be found which are less onerous and less potentially contentious to assess. 16 refs., 2 annexes.

Analog elements for transuranic chemistries

International Nuclear Information System (INIS)

Weimer, W.C.

1982-01-01

The analytical technique for measuring trace concentrations of the analog rare earth elements has been refined for optimal detection. The technique has been used to determine the rare earth concentrations in a series of geological and biological materials, including samples harvested from controlled lysimeter investigations. These studies have demonstrated that any of the trivalent rare earth elements may be used as analog elements for the trivalent transuranics, americium and curium

Analogy, explanation, and proof

Science.gov (United States)

Hummel, John E.; Licato, John; Bringsjord, Selmer

2014-01-01

People are habitual explanation generators. At its most mundane, our propensity to explain allows us to infer that we should not drink milk that smells sour; at the other extreme, it allows us to establish facts (e.g., theorems in mathematical logic) whose truth was not even known prior to the existence of the explanation (proof). What do the cognitive operations underlying the inference that the milk is sour have in common with the proof that, say, the square root of two is irrational? Our ability to generate explanations bears striking similarities to our ability to make analogies. Both reflect a capacity to generate inferences and generalizations that go beyond the featural similarities between a novel problem and familiar problems in terms of which the novel problem may be understood. However, a notable difference between analogy-making and explanation-generation is that the former is a process in which a single source situation is used to reason about a single target, whereas the latter often requires the reasoner to integrate multiple sources of knowledge. This seemingly small difference poses a challenge to the task of marshaling our understanding of analogical reasoning to understanding explanation. We describe a model of explanation, derived from a model of analogy, adapted to permit systematic violations of this one-to-one mapping constraint. Simulation results demonstrate that the resulting model can generate explanations for novel explananda and that, like the explanations generated by human reasoners, these explanations vary in their coherence. PMID:25414655

Analogy, Explanation, and Proof

Directory of Open Access Journals (Sweden)

John eHummel

2014-11-01

Full Text Available People are habitual explanation generators. At its most mundane, our propensity to explain allows us to infer that we should not drink milk that smells sour; at the other extreme, it allows us to establish facts (e.g., theorems in mathematical logic whose truth was not even known prior to the existence of the explanation (proof. What do the cognitive operations underlying the (inductive inference that the milk is sour have in common with the (deductive proof that, say, the square root of two is irrational? Our ability to generate explanations bears striking similarities to our ability to make analogies. Both reflect a capacity to generate inferences and generalizations that go beyond the featural similarities between a novel problem and familiar problems in terms of which the novel problem may be understood. However, a notable difference between analogy-making and explanation-generation is that the former is a process in which a single source situation is used to reason about a single target, whereas the latter often requires the reasoner to integrate multiple sources of knowledge. This small-seeming difference poses a challenge to the task of marshaling our understanding of analogical reasoning in the service of understanding explanation. We describe a model of explanation, derived from a model of analogy, adapted to permit systematic violations of this one-to-one mapping constraint. Simulation results demonstrate that the resulting model can generate explanations for novel explananda and that, like the explanations generated by human reasoners, these explanations vary in their coherence.

Insulin analogs with improved pharmacokinetic profiles.

Science.gov (United States)

Brange; Vølund

1999-02-01

The aim of insulin replacement therapy is to normalize blood glucose in order to reduce the complications of diabetes. The pharmacokinetics of the traditional insulin preparations, however, do not match the profiles of physiological insulin secretion. The introduction of the rDNA technology 20 years ago opened new ways to create insulin analogs with altered properties. Fast-acting analogs are based on the idea that an insulin with less tendency to self-association than human insulin would be more readily absorbed into the systemic circulation. Protracted-acting analogs have been created to mimic the slow, steady rate of insulin secretion in the fasting state. The present paper provides a historical review of the efforts to change the physicochemical and pharmacological properties of insulin in order to improve insulin therapy. The available clinical studies of the new insulins are surveyed and show, together with modeling results, that new strategies for optimal basal-bolus treatment are required for utilization of the new fast-acting analogs.

Los pasiegos. La analogía salvaje y lo salvaje de la analogía

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JAIME DE LA CALLE VALVERDE

2007-01-01

-entendiendo salvaje como un pensamiento humano prístino-: por un lado en sus relaciones con el racionalismo (¿emerge la analogía desde el racionalismo?, ¿qué relación guarda con éste?, ¿su nacimiento es resultado de una función «natural»? y por otro sobre la naturaleza social de lo salvaje a partir de las bases sociales que lo producen. Es decir, se rastrea lo que de salvaje tiene la analogía, si la analogía es o no una función ahistórica y asocial del intelecto humano. No se examina todo el complejo analógico de los pasiegos, únicamente aquél que establece relaciones homólogas entre las vacas y el entorno.

How the creative use of analogies can shape medical practice.

Science.gov (United States)

Prasad, G V Ramesh

2015-06-01

Analogical reasoning is central to medical progress, and is either creative or conservative. According to Hofmann et al., conservative analogy relates concepts from old technology to new technologies with emphasis on preservation of comprehension and conduct. Creative analogy however brings new understanding to new technology, brings similarities existing in the source domain to a target domain where they previously had no bearing, and imports something entirely different from the content of the analogy itself. I defend the claim that while conservative analogies are useful by virtue of being comfortable to use from familiarity and experience, and are more easily accepted by society, they only lead to incremental advances in medicine. However, creative analogies are more exciting and productive because they generate previously unexpected associations across widely separated domains, emphasize relations over physical similarities, and structure over superficiality. I use kidney transplantation and anti-rejection medication development as an exemplar of analogical reasoning used to improve medical practice. Anti-rejection medication has not helped highly sensitized patients because of their propensity to rejecting most organs. I outline how conservative analogical reasoning led to anti-rejection medication development, but creative analogical reasoning helped highly sensitized and blood type incompatible patients through domino transplants, by which they obtain a kidney to which they are not sensitized. Creative analogical reasoning is more likely than conservative analogical reasoning to lead to revolutionary progress. While these analogies overlap and creative analogies eventually become conservative, progress is best facilitated by combining conservative and creative analogical reasoning. © 2015 John Wiley & Sons, Ltd.

Analogs for transuranic elements

International Nuclear Information System (INIS)

Weimer, W.C.; Laul, J.C.; Kutt, J.C.

1981-01-01

A combined theoretical and experimental approach is being used to estimate the long-term environmental and biogeochemical behaviors of selected transuranic elements. The objective of this research is to estimate the effect that long-term (hundreds of years) environmental weathering has on the behavior of the transuranic elements americium and curium. This is achieved by investigating the actual behavior of naturally occurring rare earth elements, especially neodymium, that serve as transuranic analogs. Determination of the analog element behavior provides data that can be used to estimate the ultimate availability to man of transuranic materials released into the environment

23rd workshop on Advances in Analog Circuit Design

CERN Document Server

Baschirotto, Andrea; Makinwa, Kofi

2015-01-01

This book is based on the 18 tutorials presented during the 23rd workshop on Advances in Analog Circuit Design.  Expert designers present readers with information about a variety of topics at the frontier of analog circuit design, serving as a valuable reference to the state-of-the-art, for anyone involved in analog circuit research and development.    • Includes coverage of high-performance analog-to-digital and digital to analog converters, integrated circuit design in scaled technologies, and time-domain signal processing; • Provides a state-of-the-art reference in analog circuit design, written by experts from industry and academia; • Presents material in a tutorial-based format.

Bayesian analogy with relational transformations.

Science.gov (United States)

Lu, Hongjing; Chen, Dawn; Holyoak, Keith J

2012-07-01

How can humans acquire relational representations that enable analogical inference and other forms of high-level reasoning? Using comparative relations as a model domain, we explore the possibility that bottom-up learning mechanisms applied to objects coded as feature vectors can yield representations of relations sufficient to solve analogy problems. We introduce Bayesian analogy with relational transformations (BART) and apply the model to the task of learning first-order comparative relations (e.g., larger, smaller, fiercer, meeker) from a set of animal pairs. Inputs are coded by vectors of continuous-valued features, based either on human magnitude ratings, normed feature ratings (De Deyne et al., 2008), or outputs of the topics model (Griffiths, Steyvers, & Tenenbaum, 2007). Bootstrapping from empirical priors, the model is able to induce first-order relations represented as probabilistic weight distributions, even when given positive examples only. These learned representations allow classification of novel instantiations of the relations and yield a symbolic distance effect of the sort obtained with both humans and other primates. BART then transforms its learned weight distributions by importance-guided mapping, thereby placing distinct dimensions into correspondence. These transformed representations allow BART to reliably solve 4-term analogies (e.g., larger:smaller::fiercer:meeker), a type of reasoning that is arguably specific to humans. Our results provide a proof-of-concept that structured analogies can be solved with representations induced from unstructured feature vectors by mechanisms that operate in a largely bottom-up fashion. We discuss potential implications for algorithmic and neural models of relational thinking, as well as for the evolution of abstract thought. Copyright 2012 APA, all rights reserved.

Non-antibiotic selection systems for soybean somatic embryos: the lysine analog aminoethyl-cysteine as a selection agent

Directory of Open Access Journals (Sweden)

Kwanyuen Prachuab

2009-11-01

Full Text Available Abstract Background In soybean somatic embryo transformation, the standard selection agent currently used is hygromycin. It may be preferable to avoid use of antibiotic resistance genes in foods. The objective of these experiments was to develop a selection system for producing transgenic soybean somatic embryos without the use of antibiotics such as hygromycin. Results When tested against different alternate selection agents our studies show that 0.16 μg/mL glufosinate, 40 mg/L isopropylamine-glyphosate, 0.5 mg/mL (S-(2 aminoethyl-L-cysteine (AEC and the acetolactate synthase (ALS inhibitors Exceed® and Synchrony® both at 150 μg/mL inhibited soybean somatic embryo growth. Even at the concentration of 2 mg/mL, lysine+threonine (LT were poor selection agents. The use of AEC may be preferable since it is a natural compound. Unlike the plant enzyme, dihydrodipicolinate synthase (DHPS from E. coli is not feed-back inhibited by physiological concentrations of lysine. The dapA gene which codes for E. coli DHPS was expressed in soybean somatic embryos under the control of the CaMV 35S promoter. Following introduction of the construct into embryogenic tissue of soybean, transgenic events were recovered by incubating the tissue in liquid medium containing AEC at a concentration of 5 mM. Only transgenic soybeans were able to grow at this concentration of AEC; no escapes were observed. Conclusion Genetically engineered soybeans expressing a lysine insensitive DHPS gene can be selected with the non-antibiotic selection agent AEC. We also report here the inhibitory effects of glufosinate, (isopropylamine-glyphosate (Roundup®, AEC and the ALS inhibitors Exceed® and Synchrony® against different tissues of soybean

Analogical reasoning for reliability analysis based on generic data

Energy Technology Data Exchange (ETDEWEB)

Kozin, Igor O

1996-10-01

The paper suggests using the systemic concept 'analogy' for the foundation of an approach to analyze system reliability on the basis of generic data, describing the method of structuring the set that defines analogical models, an approach of transition from the analogical model to a reliability model and a way of obtaining reliability intervals of analogous objects.

Analogical reasoning for reliability analysis based on generic data

International Nuclear Information System (INIS)

Kozin, Igor O.

1996-01-01

The paper suggests using the systemic concept 'analogy' for the foundation of an approach to analyze system reliability on the basis of generic data, describing the method of structuring the set that defines analogical models, an approach of transition from the analogical model to a reliability model and a way of obtaining reliability intervals of analogous objects

Analog electronics for radiation detection

CERN Document Server

2016-01-01

Analog Electronics for Radiation Detection showcases the latest advances in readout electronics for particle, or radiation, detectors. Featuring chapters written by international experts in their respective fields, this authoritative text: Defines the main design parameters of front-end circuitry developed in microelectronics technologies Explains the basis for the use of complementary metal oxide semiconductor (CMOS) image sensors for the detection of charged particles and other non-consumer applications Delivers an in-depth review of analog-to-digital converters (ADCs), evaluating the pros and cons of ADCs integrated at the pixel, column, and per-chip levels Describes incremental sigma delta ADCs, time-to-digital converter (TDC) architectures, and digital pulse-processing techniques complementary to analog processing Examines the fundamental parameters and front-end types associated with silicon photomultipliers used for single visible-light photon detection Discusses pixel sensors ...

Q-sort assessment vs visual analog scale in the evaluation of smile esthetics.

Science.gov (United States)

Schabel, Brian J; McNamara, James A; Franchi, Lorenzo; Baccetti, Tiziano

2009-04-01

This study was designed to compare the reliability of the Q-sort and visual analog scale (VAS) methods for the assessment of smile esthetics. Furthermore, agreement between orthodontists and parents of orthodontic patients, and between male and female raters, was assessed in terms of subjective evaluation of the smile. Clinical photographs and digital video captures of 48 orthodontically treated patients were rated by 2 panels: 25 experienced orthodontists (15 men, 10 women) and 20 parents of the patients (8 men, 12 women). Interrater reliability of the Q-sort and VAS methods was evaluated by using single-measure and average-measure intraclass correlation (ICC). Kappa agreement and the McNemar test were used to evaluate agreement between orthodontists and parents, and between men and women, for "attractive" and "unattractive" images of smiles captured with clinical photography. The single-measure ICC coefficients showed fair to good reliability of the Q-sort and poor reliability of the VAS for measuring esthetic preferences of an individual orthodontist or parent. Both rating groups agreed significantly (P >0.05) on the total percentage of "attractive" images of smiles captured with clinical photography. Men and women, however, significantly disagreed on the total percentages of "attractive" and "unattractive" smiles. Women rated higher percentages of both image groups as "attractive" than did their male counterparts. The Q-sort was more reliable than the VAS for measuring smile esthetics. Orthodontists and parents of orthodontic patients agreed with respect to "attractive" and "unattractive" smiles. Men and women agreed poorly with respect to "attractive" and "unattractive" smiles.

DYN1: a 66 MHz front end analog memory chip with first level trigger capture for use in future high luminosity particle physics experiments

International Nuclear Information System (INIS)

Anghinolfi, F.; Aspell, P.; Bonino, R.; Campbell, D.; Campbell, M.; Clark, A.G.; Heijne, E.H.M.; Jarron, P.; Santiard, J.C.; Verweij, H.

1994-01-01

DYN1 is a 32 channel, 128 cell analog memory with continuous write and read access. The chip amplifies the detector signals and integrates the signal currents onto capacitors within the memory during each bunch crossing interval. Dense dynamic logic circuitry accepts multiple first level triggers, freezes the corresponding analog data and stores their addresses in an external FIFO. The triggered data can then be read out at leisure whilst simultaneously sampling and storing new triggered events. A first level trigger latency of up to 2 μs is accepted at the maximum LHC clock frequency of 66 MHz. The chip shows an overall gain of 48.2 mV/25 000 e - . The mean channel noise is 4.5 mV and the pedestal variation from cell to cell within one channel is 1.9 mV. The total dynamic range has been measured at 4.6 V giving a resolution of 11 bits (0.05%) for the memory itself. (orig.)

Co-creating value through agents interaction within service network

International Nuclear Information System (INIS)

Okdinawati, L.; Simatupang, T.M.; Sunitiyoso, Y.

2017-01-01

The purpose of this paper is to gives further understanding on value co-creation mechanisms in B-to-B service network by reinforcing the processes, the relationships, and influences of other agents where Collaborative Transportation Management (CTM) forms might be best employed. Design/methodology/approach: In order to model the interactions among agents in the collaboration processes and the value co-creation processes, this research used three collaboration cases in Indonesia. Then, the agent-based simulation was used to capture both the collaboration process and the value co-creation process of the three collaboration cases. Findings: The interactions among the agents both inside and outside their collaboration environment determined agent’s role as a value co-creator. The willingness of an agent to accept the opinion of another agent determined the degree of their willingness to co-operate and to change their strategies, and perceptions. Therefore, influenced the size of the value obtained by them in each collaboration process. Research limitations/implications: The findings of the simulations subject to assumptions based on the collaboration cases. Further research is related to how to encourage agents to co-operate and adjust their perceptions. Practical implications: It is crucial for the practitioners to interact with another agent both inside and outside their collaboration environment. The opinions of another agent inside the collaboration environment also need to be considered. Originality/value: This research is derived from its emphasis on how a value is co-created by reinforcing both the collaborative processes and the interactions among agents as well as on how CTM might be best employed.

Co-creating value through agents interaction within service network

Energy Technology Data Exchange (ETDEWEB)

Okdinawati, L.; Simatupang, T.M.; Sunitiyoso, Y.

2017-07-01

The purpose of this paper is to gives further understanding on value co-creation mechanisms in B-to-B service network by reinforcing the processes, the relationships, and influences of other agents where Collaborative Transportation Management (CTM) forms might be best employed. Design/methodology/approach: In order to model the interactions among agents in the collaboration processes and the value co-creation processes, this research used three collaboration cases in Indonesia. Then, the agent-based simulation was used to capture both the collaboration process and the value co-creation process of the three collaboration cases. Findings: The interactions among the agents both inside and outside their collaboration environment determined agent’s role as a value co-creator. The willingness of an agent to accept the opinion of another agent determined the degree of their willingness to co-operate and to change their strategies, and perceptions. Therefore, influenced the size of the value obtained by them in each collaboration process. Research limitations/implications: The findings of the simulations subject to assumptions based on the collaboration cases. Further research is related to how to encourage agents to co-operate and adjust their perceptions. Practical implications: It is crucial for the practitioners to interact with another agent both inside and outside their collaboration environment. The opinions of another agent inside the collaboration environment also need to be considered. Originality/value: This research is derived from its emphasis on how a value is co-created by reinforcing both the collaborative processes and the interactions among agents as well as on how CTM might be best employed.

Anthropomorphism--Matters or Not? On Agent Modality and Its Implications for Teaching English Idioms and Design Decisions

Science.gov (United States)

Ahmadi, Alireza; Sahragard, Rahman; Babaie Shalmani, Hamed

2017-01-01

The present study aimed to examine whether agent-based instruction would privilege English as a Foreign Language (EFL) learners any better than mainstream approaches (e.g. analogical reasoning, guessing from context, image formation, semantic analysis, etc.) when it comes to the teaching of English idioms. It also sought to explore whether…

Analogical Matrices in Young Children and Students with Intellectual Disability: Reasoning by Analogy or Reasoning by Association?

Science.gov (United States)

Denaes, Caroline

2012-01-01

Background: Analogical reasoning (AR) is renowned for being a complex activity. Young children tend to reason by association, rather by analogy, and people with intellectual disability present problems of memorization. Both these populations usually show low performances in AR. The present author investigated whether familiar material and external…

A hierarchical spatiotemporal analog forecasting model for count data.

Science.gov (United States)

McDermott, Patrick L; Wikle, Christopher K; Millspaugh, Joshua

2018-01-01

Analog forecasting is a mechanism-free nonlinear method that forecasts a system forward in time by examining how past states deemed similar to the current state moved forward. Previous applications of analog forecasting has been successful at producing robust forecasts for a variety of ecological and physical processes, but it has typically been presented in an empirical or heuristic procedure, rather than as a formal statistical model. The methodology presented here extends the model-based analog method of McDermott and Wikle (Environmetrics, 27, 2016, 70) by placing analog forecasting within a fully hierarchical statistical framework that can accommodate count observations. Using a Bayesian approach, the hierarchical analog model is able to quantify rigorously the uncertainty associated with forecasts. Forecasting waterfowl settling patterns in the northwestern United States and Canada is conducted by applying the hierarchical analog model to a breeding population survey dataset. Sea surface temperature (SST) in the Pacific Ocean is used to help identify potential analogs for the waterfowl settling patterns.

Selective cytotoxicity of the antibacterial peptide ABP-dHC-Cecropin A and its analog towards leukemia cells.

Science.gov (United States)

Sang, Ming; Zhang, Jiaxin; Zhuge, Qiang

2017-05-15

Some cationic antibacterial peptides, with typical amphiphilic α-helical conformations in a membrane-mimicking environment, exhibit anticancer properties as a result of a similar mechanism of action towards both bacteria and cancer cells. We previously reported the cDNA sequence of the antimicrobial peptide ABP-dHC-Cecropin A precursor cloned from drury (Hyphantria cunea) (dHC). In the present study, we synthesized and structurally characterized ABP-dHC-Cecropin A and its analog, ABP-dHC-Cecropin A-K(24). Circular dichroism spectroscopy showed that ABP-dHC-Cecropin A and its analog adopt a well-defined α-helical structure in a 50% trifluorethanol solution. The cytotoxicity and cell selectivity of these peptides were further examined in three leukemia cell lines and two non-cancerous cell lines. The MTT assay indicated both of these peptides have a concentration-dependent cytotoxic effect in leukemia cells, although the observed cytotoxicity was greater with ABP-dHC-Cecropin A-K(24) treatment, whereas they were not cytotoxic towards the non-cancerous cell lines. Moreover, ABP-dHC-Cecropin A and its analog had a lower hemolytic effect in human red blood cells. Together, these results suggest the peptides are selectively cytotoxic towards leukemia cells. Confocal laser scanning microscopy determined that the peptides were concentrated at the surface of the leukemia cells, and changes in the cell membrane were determined with a permeability assay, which suggested that the anticancer activity of ABP-dHC-Cecropin A and its analog is a result of its presence at the leukemia cell membrane. ABP-dHC-Cecropin A and its analog may represent a novel anticancer agent for leukemia therapy, considering its cancer cell selectivity and relatively low cytotoxicity in normal cells. Copyright © 2017 Elsevier B.V. All rights reserved.

Molecular interactions between (--epigallocatechin gallate analogs and pancreatic lipase.

Directory of Open Access Journals (Sweden)

Shihui Wang

Full Text Available The molecular interactions between pancreatic lipase (PL and four tea polyphenols (EGCG analogs, like (--epigallocatechin gallate (EGCG, (--gallocatechin gallate (GCG, (--epicatechin gallate (ECG, and (--epigallocatechin (EC, were studied from PL activity, conformation, kinetics and thermodynamics. It was observed that EGCG analogs inhibited PL activity, and their inhibitory rates decreased by the order of EGCG>GCG>ECG>EC. PL activity at first decreased rapidly and then slowly with the increase of EGCG analogs concentrations. α-Helix content of PL secondary structure decreased dependent on EGCG analogs concentration by the order of EGCG>GCG>ECG>EC. EGCG, ECG, and EC could quench PL fluorescence both dynamically and statically, while GCG only quenched statically. EGCG analogs would induce PL self-assembly into complexes and the hydrodynamic radii of the complexes possessed a close relationship with the inhibitory rates. Kinetics analysis showed that EGCG analogs non-competitively inhibited PL activity and did not bind to PL catalytic site. DSC measurement revealed that EGCG analogs decreased the transition midpoint temperature of PL enzyme, suggesting that these compounds reduced PL enzyme thermostability. In vitro renaturation through urea solution indicated that interactions between PL and EGCG analogs were weak and non-covalent.

Functional DNA: Teaching Infinite Series through Genetic Analogy

Science.gov (United States)

Kowalski, R. Travis

2011-01-01

This article presents an extended analogy that connects infinite sequences and series to the science of genetics, by identifying power series as "DNA for a function." This analogy allows standard topics such as convergence tests or Taylor approximations to be recast in a "forensic" light as mathematical analogs of genetic concepts such as DNA…

Radiative electron capture

International Nuclear Information System (INIS)

Biggerstaff, J.A.; Appleton, B.R.; Datz, S.; Moak, C.D.; Neelavathi, V.N.; Noggle, T.S.; Ritchie, R.H.; VerBeek, H.

1975-01-01

Some data are presented for radiative electron capture by fast moving ions. The radiative electron capture spectrum is shown for O 8+ in Ag, along with the energy dependence of the capture cross-section. A discrepancy between earlier data, theoretical prediction, and the present data is pointed out. (3 figs) (U.S.)

Analog techniques in CEBAF's RF control system

International Nuclear Information System (INIS)

Hovater, C.; Fugitt, J.

1989-01-01

Recent developments in high-speed analog technology have progressed into the areas of traditional RF technology. Diode related devices are being replaced by analog IC's in the CEBAF RF control system. Complex phase modulators and attenuators have been successfully tested at 70 MHz. They have three advantages over existing technology: lower cost, less temperature sensitivity, and more linearity. RF signal conditioning components and how to implement the new analog IC's will be covered in this paper. 4 refs., 5 figs

Analog techniques in CEBAF'S RF control system

International Nuclear Information System (INIS)

Hovater, C.; Fugitt, J.

1989-01-01

Recent developments in high-speed analog technology have progressed into the areas of traditional rf technology. Diode-related devices are being replaced by analog IC's in the CEBAF rf control system. Complex phase modulators and attenuators have been successfully tested at 70 MHz. They have three advantages over existing technology: lower cost, less temperature sensitivity, and more linearity. Rf signal conditioning components and how to implement the new analog IC's will be covered in this paper. 4 refs., 5 figs

Benefit of Analog, Programmable and Digital Hearing Aids

Directory of Open Access Journals (Sweden)

Jamileh Fatahi

2006-12-01

Full Text Available Background and Aims: As the hearing aid technology progressively promotes toward replacing analog hearing aids with digital and programmable ones, comparison of the patient satisfaction of those kinds of hearing aids by means of a valuable tool seems so necessary. So, the aim of this study was to compare self-reported benefit of analog, digitally controlled programmable and digital hearing aids for reducing disability caused by hearing impairment in mild to severe sensorineural hearing impaired persons. Materials and Methods: This cross-sectional study was performed on 90 persons with mild to severe sensorineural hearing loss dividing into three groups: 43 subjects were fitted with digital, 15 with programmable, 32 with analog hearing aids. After pure tone audiometry, Abbreviated profile of hearing aid benefit (APHAB was completed before and one month after using hearing aids to determine the benefit of them. Results: Global APHAB mean scores for digital, programmable and analog hearing aids were 49.05, 33.19 and 39.53, respectively. Ease of Communication subscale mean scores were 53.46 for digitals, 37.66 for programmables and 39.09 for analogs. Background noise subscale mean scores for digital programmable and analog hearing aids were 46.36, 25.53 and 35.31, respectively. Global and also both subscale mean scores showed significant difference between digital hearing aids and programmable and analog ones. There was no significant difference between reverberation subscale mean scores of three groups. Conclusion: It seems digital hearing aids may be more beneficial to reduce disability caused by hearing loss than analog and programmable hearing aids are.

ANALOGICAL REASONING USING TRANSFORMATIONS OF RULES

OpenAIRE

Haraguchi, Makoto; 原口, 誠

1986-01-01

A formalism of analogical reasoning is presented. The analogical reasoning can be considered as a deduction with a function of transforming logical rules. From this viewpoint, the reasoning is defined in terms of deduction, and is therefore realized in a logic programming system. The reasoning system is described as an extension of Prolog interpreter.

Determination of the Electron Neutrino Mass from Experiments on Electron-Capture Beta-Decay (EC)

CERN Multimedia

2002-01-01

The aim of the programme is to measure the electron-neutrino mass, for which at present an upper limit of 500~eV is known. \\\\ \\\\ The experiment studies the shape of the internal bremsstrahlung spectrum in electron-capture near its upper end-point and deduces a mass from small shape changes completely analogous to those in the well-known determination of the electron antineutrino mass in the tritium beta-minus decay. \\\\ \\\\ In a low-energy bremsstrahlung process, the capture takes place from a virtual S state associated with a radiative P~@A~S electromagnetic transition, and the resonant nature of the process leads to important enhancements of the photon intensities at low energy, in particular near the resonance energies co (X-rays). This effect gives this type of experiment a chance to compete with experiments on continuous beta spectra. \\\\ \\\\ The programme concentrates on two long-lived isotopes: \\\\ \\\\ 1)~~|1|6|3Ho. The Q value for this isotope has been found to be 2.6-2.7 keV. A detector specially construct...

Proceedings of workshop on 'boron chemistry and boron neutron capture therapy'

International Nuclear Information System (INIS)

Kitaoka, Yoshinori

1993-09-01

This volume contains the proceedings of the 5th Workshop on 'the Boron Chemistry and Boron Neutron Capture Therapy' held on February 22 in 1993. The solubility of the boron carrier play an important role in the BNCT. New water-soluble p-boronophenylalanine derivatives are synthesized and their biological activities are investigated (Chap. 2 and 3). Some chemical problems on the BNCT were discussed, and the complex formation reaction of hydroxylboryl compounds were studied by the paper electrophoresis (Chap. 4). The results of the medical investigation on the BNCT using BSH compounds are shown in Chap. 5. Syntheses of o- and m-boronophenylalanine were done and their optical resolution was tried (Chap. 6). The complex formation reaction of p-boronophenylalanine (BPA) with L-DOPA and the oxidation reaction of the analogs are found in Chap. 7. The pka of BPA were determined by the isotachophoresis (Chap. 8). The chemical nature of dihydroxyboryl compounds were investigated by an infrared spectroscopy and electrophoresis (Chap. 9). New synthetic methods of BPA and p-boronophenylserine using ester of isocyanoacetic acid are described in Chap. 10. The induction of chromosomal aberations by neutron capture reaction are discussed from a point of the biological view. The a of the presented papers are indexed individually. (J.P.N.)

NOx reduction using amine reclaimer wastes (ARW) generated in post combustion CO2 capture

DEFF Research Database (Denmark)

Botheju, Deshai; Glarborg, Peter; Tokheim, Lars-Andre

2012-01-01

Amine reclaimer wastes (ARW) generated in CO2 capture processes demand suitable disposal means. Such wastes contain remaining amine, NH3 and other degradation compounds. This study investigated the potential of using ARW as a NOx reducing agent, under laboratory conditions in a flow reactor....../NO ratios (waste product, together with its demonstrated NOx reduction capability and its calorific value contribution, makes it attractive as an additive...

Polyunsaturated fatty acids synergize with lipid droplet binding thalidomide analogs to induce oxidative stress in cancer cells

Directory of Open Access Journals (Sweden)

Madácsi Ramóna

2010-06-01

Full Text Available Abstract Background Cytoplasmic lipid-droplets are common inclusions of eukaryotic cells. Lipid-droplet binding thalidomide analogs (2,6-dialkylphenyl-4/5-amino-substituted-5,6,7-trifluorophthalimides with potent anticancer activities were synthesized. Results Cytotoxicity was detected in different cell lines including melanoma, leukemia, hepatocellular carcinoma, glioblastoma at micromolar concentrations. The synthesized analogs are non-toxic to adult animals up to 1 g/kg but are teratogenic to zebrafish embryos at micromolar concentrations with defects in the developing muscle. Treatment of tumor cells resulted in calcium release from the endoplasmic reticulum (ER, induction of reactive oxygen species (ROS, ER stress and cell death. Antioxidants could partially, while an intracellular calcium chelator almost completely diminish ROS production. Exogenous docosahexaenoic acid or eicosapentaenoic acid induced calcium release and ROS generation, and synergized with the analogs in vitro, while oleic acid had no such an effect. Gene expression analysis confirmed the induction of ER stress-mediated apoptosis pathway components, such as GADD153, ATF3, Luman/CREB3 and the ER-associated degradation-related HERPUD1 genes. Tumor suppressors, P53, LATS2 and ING3 were also up-regulated in various cell lines after drug treatment. Amino-phthalimides down-regulated the expression of CCL2, which is implicated in tumor metastasis and angiogenesis. Conclusions Because of the anticancer, anti-angiogenic action and the wide range of applicability of the immunomodulatory drugs, including thalidomide analogs, lipid droplet-binding members of this family could represent a new class of agents by affecting ER-membrane integrity and perturbations of ER homeostasis.

Antiproliferative effects of an analog of curcumin in Hep-2 cells: a comparative study with curcumin.

Science.gov (United States)

Kumaravel, Mohankumar; Sankar, Pajaniradje; Latha, Periyasamy; Benson, Chellakan S; Rukkumani, Rajagopalan

2013-02-01

Curcumin, the major active principle of Curcuma longa, is one of the promising, plant-derived, chemopreventive agents being studied for its anticarcinogenic and antioxidant properties. Hence, in our study, we aimed at testing the antiproliferative efficacy of an o-hydroxyl substituted analog of curcumin, bis demethoxy curcumin analog (BDMC-A), and comparing its efficacy with that of curcumin. BDMC-A was synthesised with a yield of 78% and 98% purity. Hep-2 cells and the MTT cell viability assay were used to examine cell proliferation. LDH assay and cell counts were performed to assess the cytotoxicity and anti-proliferative effects of the compound, respectively. Flow cytometry followed by Western blot were performed to investigate the cell cycle distribution. BDMC-A inhibited cell proliferation at a much lower concentration (IC50 20 microM) than curcumin (IC50 50 microM). Similar effects were observed in the LDH release and cell count assays. Flow cytometric studies using propidium iodide showed accumulation of cells in the G0/G1 phase and the arrest was further confirmed by immunoblotting of protein cyclin D1. BDMC-A was more potent in inhibiting the cells at a lower dose when compared with curcumin. Our results showed that the analog of curcumin is likely to possess more efficacy compared with curcumin in inhibiting cancer.

Josephson junction analog and quasiparticle-pair current

DEFF Research Database (Denmark)

Bak, Christen Kjeldahl; Pedersen, Niels Falsig

1973-01-01

A close analogy exists between a Josephson junction and a phase-locked loop. A new type of electrical analog based on this principle is presented. It is shown that the inclusion in this analog of a low-pass filter gives rise to a current of the same form as the Josephson quasiparticle-pair current....... A simple picture of the quasiparticle-pair current, which gives the right dependences, is obtained by assuming a junction cutoff frequency to be at the energy gap. ©1973 American Institute of Physics...

Fast parallel-series analog-to-digital converter

International Nuclear Information System (INIS)

Pogosov, A.Yu.

1987-01-01

Fast analog-to-digital converters are used in systems for detection of rapid processes, nuclear spectroscopy. A 12-digit analog-to-digital converter with conversion time of 160 ns and conversion frequency of 8.3 MHz is described; a segmented digital-to-analog converter with differential non-linearity of < 0.01% and a differential amplifier-limiter with setting time of 80 ns at the error of 0.2% are utilized in the converter; a control device is based on the chain of flip-flop circuit

Heterocyclic cyclohexanone monocarbonyl analogs of curcumin can inhibit the activity of ATP-binding cassette transporters in cancer multidrug resistance.

Science.gov (United States)

Revalde, Jezrael L; Li, Yan; Hawkins, Bill C; Rosengren, Rhonda J; Paxton, James W

2015-02-01

Curcumin (CUR) is a phytochemical that inhibits the xenobiotic ABC efflux transporters implicated in cancer multidrug resistance (MDR), such as P-glycoprotein (P-gp), breast cancer resistance protein (BCRP) and multidrug resistance-associated proteins 1 and 5 (MRP1 and MRP5). The use of CUR in the clinic however, is complicated by its instability and poor pharmacokinetic profile. Monocarbonyl analogs of CUR (MACs) are compounds without CUR's unstable β-diketone moiety and were reported to have improved stability and in vivo disposition. Whether the MACs can be used as MDR reversal agents is less clear, as the absence of a β-diketone may negatively impact transporter inhibition. In this study, we investigated 23 heterocyclic cyclohexanone MACs for inhibitory effects against P-gp, BCRP, MRP1 and MRP5. Using flow cytometry and resistance reversal assays, we found that many of these compounds inhibited the transport activity of the ABC transporters investigated, often with much greater potency than CUR. Overall the analogs were most effective at inhibiting BCRP and we identified three compounds, A12 (2,6-bis((E)-2,5-dimethoxy-benzylidene)cyclohexanone), A13 (2,6-bis((E)-4-hydroxyl-3-methoxybenzylidene)-cyclohexanone) and B11 (3,5-bis((E)-2-fluoro-4,5-dimethoxybenzylidene)-1-methylpiperidin-4-one), as the most promising BCRP inhibitors. These compounds inhibited BCRP activity in a non-cell line, non-substrate-specific manner. Their inhibition occurred by direct transporter interaction rather than modulating protein or cell surface expression. From these results, we concluded that MACs, such as the heterocyclic cyclohexanone analogs in this study, also have potential as MDR reversal agents and may be superior alternatives to the unstable parent compound, CUR. Copyright © 2014 Elsevier Inc. All rights reserved.

CMOS Analog IC Design: Fundamentals

OpenAIRE

Bruun, Erik

2018-01-01

This book is intended for use as the main textbook for an introductory course in CMOS analog integrated circuit design. It is aimed at electronics engineering students who have followed basic courses in mathematics, physics, circuit theory, electronics and signal processing. It takes the students directly from a basic level to a level where they can start working on simple analog IC design projects or continue their studies using more advanced textbooks in the field. A distinct feature of thi...

Cyclopentanoid analogs of phosphatidylcholine: susceptibility to phospholipase A2.

Science.gov (United States)

Lister, M D; Hancock, A J

1988-10-01

Six isomers of dipalmitoylcyclopentanetriol phosphocholine (cyclopentano-lecithin) were tested as potential substrates for phospholipase A2. Since each of these analogs possesses a configuration that mimics a narrow range of conformations of a glycerophospholipid molecule, the analogs were used to assess the enzyme's conformational requirements. Studies showed that all of the analogs containing the phosphocholine at the C-1 (or C-3) position could be hydrolyzed, while only one of the three analogs that contains the polar head group at the C-2 position was susceptible. Kinetic studies, however, revealed that only the all-trans-(1,3/2-1P)-cyclopentano-lecithin gave initial rates of hydrolysis that were measurable by pH-stat. Acyl group specificity of the enzyme towards the all-trans isomer was determined with an analog was acyl groups were distinguishable. The synthesis of this mixed-acid-cyclopentano-PC is described herein. When this analog was enzymatically assayed, results unequivocally showed the enzyme to be specific for C-2 acyl hydrolysis. This specificity, and data showing that the all-trans analog is stereospecifically hydrolyzed, indicate that it is acted on in an analogous manner to dipalmitoylphosphatidylcholine. These studies indicate that although the configuration of the analog is not necessarily a prerequisite for hydrolysis, there does appear to be an optimal spatial orientation for enzymatic activity. The analogy between the susceptibilities of all-trans-(1,3/2-1P)-cyclopentano-lecithin and glycero-lecithin suggests that the conformation of the glycero-lecithin during phospholipase A2-mediated hydrolysis may be best simulated by the all-trans orientation of C-O bonds in the artificial substrate.

NaturAnalogs for the Unsaturated Zone

Energy Technology Data Exchange (ETDEWEB)

A. Simmons; A. Unger; M. Murrell

2000-03-08

The purpose of this Analysis/Model Report (AMR) is to document natural and anthropogenic (human-induced) analog sites and processes that are applicable to flow and transport processes expected to occur at the potential Yucca Mountain repository in order to build increased confidence in modeling processes of Unsaturated Zone (UZ) flow and transport. This AMR was prepared in accordance with ''AMR Development Plan for U0135, Natural Analogs for the UZ'' (CRWMS 1999a). Knowledge from analog sites and processes is used as corroborating information to test and build confidence in flow and transport models of Yucca Mountain, Nevada. This AMR supports the Unsaturated Zone (UZ) Flow and Transport Process Model Report (PMR) and the Yucca Mountain Site Description. The objectives of this AMR are to test and build confidence in the representation of UZ processes in numerical models utilized in the UZ Flow and Transport Model. This is accomplished by: (1) applying data from Boxy Canyon, Idaho in simulations of UZ flow using the same methodologies incorporated in the Yucca Mountain UZ Flow and Transport Model to assess the fracture-matrix interaction conceptual model; (2) Providing a preliminary basis for analysis of radionuclide transport at Pena Blanca, Mexico as an analog of radionuclide transport at Yucca Mountain; and (3) Synthesizing existing information from natural analog studies to provide corroborating evidence for representation of ambient and thermally coupled UZ flow and transport processes in the UZ Model.

Analogy, higher order thinking, and education.

Science.gov (United States)

Richland, Lindsey Engle; Simms, Nina

2015-01-01

Analogical reasoning, the ability to understand phenomena as systems of structured relationships that can be aligned, compared, and mapped together, plays a fundamental role in the technology rich, increasingly globalized educational climate of the 21st century. Flexible, conceptual thinking is prioritized in this view of education, and schools are emphasizing 'higher order thinking', rather than memorization of a cannon of key topics. The lack of a cognitively grounded definition for higher order thinking, however, has led to a field of research and practice with little coherence across domains or connection to the large body of cognitive science research on thinking. We review literature on analogy and disciplinary higher order thinking to propose that relational reasoning can be productively considered the cognitive underpinning of higher order thinking. We highlight the utility of this framework for developing insights into practice through a review of mathematics, science, and history educational contexts. In these disciplines, analogy is essential to developing expert-like disciplinary knowledge in which concepts are understood to be systems of relationships that can be connected and flexibly manipulated. At the same time, analogies in education require explicit support to ensure that learners notice the relevance of relational thinking, have adequate processing resources available to mentally hold and manipulate relations, and are able to recognize both the similarities and differences when drawing analogies between systems of relationships. © 2015 John Wiley & Sons, Ltd.

Analog forecasting with dynamics-adapted kernels

Science.gov (United States)

Zhao, Zhizhen; Giannakis, Dimitrios

2016-09-01

Analog forecasting is a nonparametric technique introduced by Lorenz in 1969 which predicts the evolution of states of a dynamical system (or observables defined on the states) by following the evolution of the sample in a historical record of observations which most closely resembles the current initial data. Here, we introduce a suite of forecasting methods which improve traditional analog forecasting by combining ideas from kernel methods developed in harmonic analysis and machine learning and state-space reconstruction for dynamical systems. A key ingredient of our approach is to replace single-analog forecasting with weighted ensembles of analogs constructed using local similarity kernels. The kernels used here employ a number of dynamics-dependent features designed to improve forecast skill, including Takens’ delay-coordinate maps (to recover information in the initial data lost through partial observations) and a directional dependence on the dynamical vector field generating the data. Mathematically, our approach is closely related to kernel methods for out-of-sample extension of functions, and we discuss alternative strategies based on the Nyström method and the multiscale Laplacian pyramids technique. We illustrate these techniques in applications to forecasting in a low-order deterministic model for atmospheric dynamics with chaotic metastability, and interannual-scale forecasting in the North Pacific sector of a comprehensive climate model. We find that forecasts based on kernel-weighted ensembles have significantly higher skill than the conventional approach following a single analog.

Natural Analogs for the Unsaturated Zone

International Nuclear Information System (INIS)

Simmons, A.; Unger, A.; Murrell, M.

2000-01-01

The purpose of this Analysis/Model Report (AMR) is to document natural and anthropogenic (human-induced) analog sites and processes that are applicable to flow and transport processes expected to occur at the potential Yucca Mountain repository in order to build increased confidence in modeling processes of Unsaturated Zone (UZ) flow and transport. This AMR was prepared in accordance with ''AMR Development Plan for U0135, Natural Analogs for the UZ'' (CRWMS 1999a). Knowledge from analog sites and processes is used as corroborating information to test and build confidence in flow and transport models of Yucca Mountain, Nevada. This AMR supports the Unsaturated Zone (UZ) Flow and Transport Process Model Report (PMR) and the Yucca Mountain Site Description. The objectives of this AMR are to test and build confidence in the representation of UZ processes in numerical models utilized in the UZ Flow and Transport Model. This is accomplished by: (1) applying data from Boxy Canyon, Idaho in simulations of UZ flow using the same methodologies incorporated in the Yucca Mountain UZ Flow and Transport Model to assess the fracture-matrix interaction conceptual model; (2) Providing a preliminary basis for analysis of radionuclide transport at Pena Blanca, Mexico as an analog of radionuclide transport at Yucca Mountain; and (3) Synthesizing existing information from natural analog studies to provide corroborating evidence for representation of ambient and thermally coupled UZ flow and transport processes in the UZ Model

A feeding protocol for delivery of agents to assess development in Varroa mites.

Directory of Open Access Journals (Sweden)

Ana R Cabrera

Full Text Available A novel feeding protocol for delivery of bio-active agents to Varroa mites was developed by providing mites with honey bee larva hemolymph supplemented with cultured insect cells and selected materials delivered on a fibrous cotton substrate. Mites were starved, fed on treated hemolymph to deliver selected agents and then returned to bee larvae. Transcript levels of two reference genes, actin and glyceraldehyde 3-phosphate dehydrogenase (GAPDH, as well as for nine selected genes involved in reproductive processes showed that the starvation and feeding protocol periods did not pose a high level of stress to the mites as transcript levels remained comparable between phoretic mites and those completing the protocol. The feeding protocol was used to deliver molecules such as hormone analogs or plasmids. Mites fed with Tebufenozide, an ecdysone analog, had higher transcript levels of shade than untreated or solvent treated mites. In order to extend this feeding protocol, cultured insect cells were incorporated to a final ratio of 1 part cells and 2 parts hemolymph. Although supplementation with Bombyx mori Bm5 cells increased the amount of hemolymph consumed per mite, there was a significant decrease in the percentage of mites that fed and survived. On the other hand, Drosophila melanogaster S2 cells reduced significantly the percentage of mites that fed and survived as well as the amount of hemolymph consumed. The feeding protocol provides a dynamic platform with which to challenge the Varroa mite to establish efficacy of control agents for this devastating honey bee pest.

Method and apparatus for selective capture of gas phase analytes using metal .beta.-diketonate polymers

Science.gov (United States)

Harvey, Scott D [Kennewick, WA

2011-06-21

A process and sensor device are disclosed that employ metal .beta.-diketonate polymers to selectively capture gas-phase explosives and weaponized chemical agents in a sampling area or volume. The metal .beta.-diketonate polymers can be applied to surfaces in various analytical formats for detection of: improvised explosive devices, unexploded ordinance, munitions hidden in cargo holds, explosives, and chemical weapons in public areas.

Semiotics and agents for integrating and navigating through multimedia representations of concepts

Science.gov (United States)

Joyce, Dan W.; Lewis, Paul H.; Tansley, Robert H.; Dobie, Mark R.; Hall, Wendy

1999-12-01

The purpose of this paper is two-fold. We begin by exploring the emerging trend to view multimedia information in terms of low-level and high-level components; the former being feature-based and the latter the 'semantics' intrinsic to what is portrayed by the media object. Traditionally, this has been viewed by employing analogies with generative linguistics. Recently, a new perceptive based on the semiotic tradition has been alluded to in several papers. We believe this to be a more appropriate approach. From this, we propose an approach for tackling this problem which uses an associative data structure expressing authored information together with intelligent agents acting autonomously over this structure. We then show how neural networks can be used to implement such agents. The agents act as 'vehicles' for bridging the gap between multimedia semantics and concrete expressions of high-level knowledge, but we suggest that traditional neural network techniques for classification are not architecturally adequate.

Circuit with a successive approximation analog to digital converter

NARCIS (Netherlands)

Louwsma, S.M.; Vertregt, Maarten

2011-01-01

During successive approximation analog to digital conversion a series of successive digital reference values is selected that converges towards a digital representation of an analog input signal. An analog reference signal is generated dependent on the successive digital reference values and

Circuit with a successive approximation analog to digital converter

NARCIS (Netherlands)

Louwsma, S.M.; Vertregt, Maarten

2010-01-01

During successive approximation analog to digital conversion a series of successive digital reference values is selected that converges towards a digital representation of an analog input signal. An analog reference signal is generated dependent on the successive digital reference values and

16-channel analog store and multiplexer unit

Energy Technology Data Exchange (ETDEWEB)

Brossard, M; Kulka, Z [Clermont-Ferrand-2 Univ., 63 - Aubiere (France). Lab. de Physique Corpusculaire

1979-03-15

A 16-channel analog store and multiplexer unit is described. The unit enables storing and selection of analog information which is then digitally encoded by single ADC. This solution becomes economically attractive particularly in multidetector pulse height analysis systems.

Multi-rate control over AWGN channels via analog joint source-channel coding

KAUST Repository

Khina, Anatoly; Pettersson, Gustav M.; Kostina, Victoria; Hassibi, Babak

2017-01-01

We consider the problem of controlling an unstable plant over an additive white Gaussian noise (AWGN) channel with a transmit power constraint, where the signaling rate of communication is larger than the sampling rate (for generating observations and applying control inputs) of the underlying plant. Such a situation is quite common since sampling is done at a rate that captures the dynamics of the plant and which is often much lower than the rate that can be communicated. This setting offers the opportunity of improving the system performance by employing multiple channel uses to convey a single message (output plant observation or control input). Common ways of doing so are through either repeating the message, or by quantizing it to a number of bits and then transmitting a channel coded version of the bits whose length is commensurate with the number of channel uses per sampled message. We argue that such “separated source and channel coding” can be suboptimal and propose to perform joint source-channel coding. Since the block length is short we obviate the need to go to the digital domain altogether and instead consider analog joint source-channel coding. For the case where the communication signaling rate is twice the sampling rate, we employ the Archimedean bi-spiral-based Shannon-Kotel'nikov analog maps to show significant improvement in stability margins and linear-quadratic Gaussian (LQG) costs over simple schemes that employ repetition.

Multi-rate control over AWGN channels via analog joint source-channel coding

KAUST Repository

Khina, Anatoly

2017-01-05

We consider the problem of controlling an unstable plant over an additive white Gaussian noise (AWGN) channel with a transmit power constraint, where the signaling rate of communication is larger than the sampling rate (for generating observations and applying control inputs) of the underlying plant. Such a situation is quite common since sampling is done at a rate that captures the dynamics of the plant and which is often much lower than the rate that can be communicated. This setting offers the opportunity of improving the system performance by employing multiple channel uses to convey a single message (output plant observation or control input). Common ways of doing so are through either repeating the message, or by quantizing it to a number of bits and then transmitting a channel coded version of the bits whose length is commensurate with the number of channel uses per sampled message. We argue that such “separated source and channel coding” can be suboptimal and propose to perform joint source-channel coding. Since the block length is short we obviate the need to go to the digital domain altogether and instead consider analog joint source-channel coding. For the case where the communication signaling rate is twice the sampling rate, we employ the Archimedean bi-spiral-based Shannon-Kotel\\'nikov analog maps to show significant improvement in stability margins and linear-quadratic Gaussian (LQG) costs over simple schemes that employ repetition.

Contrast agent enhanced pQCT of articular cartilage

Energy Technology Data Exchange (ETDEWEB)

Kallioniemi, A S [Department of Physics, University of Kuopio, POB 1627, 70211 Kuopio (Finland); Jurvelin, J S [Department of Physics, University of Kuopio, POB 1627, 70211 Kuopio (Finland); Nieminen, M T [Department of Diagnostic Radiology, POB 50, 90029 OYS, Oulu University Hospital, Oulu (Finland); Lammi, M J [Department of Anatomy, Institute of Biomedicine, University of Kuopio, POB 1627, 70211 Kuopio (Finland); Toeyraes, J [Department of Physics, University of Kuopio, POB 1627, 70211 Kuopio (Finland)

2007-02-21

The delayed gadolinium enhanced MRI of cartilage (dGEMRIC) technique is the only non-invasive means to estimate proteoglycan (PG) content in articular cartilage. In dGEMRIC, the anionic paramagnetic contrast agent gadopentetate distributes in inverse relation to negatively charged PGs, leading to a linear relation between T{sub 1,Gd} and spatial PG content in tissue. In the present study, for the first time, contrast agent enhanced peripheral quantitative computed tomography (pQCT) was applied, analogously to dGEMRIC, for the quantitative detection of spatial PG content in cartilage. The suitability of two anionic radiographic contrast agents, gadopentetate and ioxaglate, to detect enzymatically induced PG depletion in articular cartilage was investigated. First, the interrelationships of x-ray absorption, as measured with pQCT, and the contrast agent solution concentration were investigated. Optimal contrast agent concentrations for the following experiments were selected. Second, diffusion rates for both contrast agents were investigated in intact (n = 3) and trypsin-degraded (n 3) bovine patellar cartilage. The contrast agent concentration of the cartilaginous layer was measured prior to and 2-27 h after immersion. Optimal immersion time for the further experiments was selected. Third, the suitability of gadopentetate and ioxaglate enhanced pQCT to detect the enzymatically induced specific PG depletion was investigated by determining the contrast agent concentrations and uronic acid and water contents in digested and intact osteochondral samples (n = 16). After trypsin-induced PG loss (-70%, p < 0.05) the penetration of gadopentetate and ioxaglate increased (p < 0.05) by 34% and 48%, respectively. Gadopentetate and ioxaglate concentrations both showed strong correlation (r = -0.95, r -0.94, p < 0.01, respectively) with the uronic acid content. To conclude, contrast agent enhanced pQCT provides a technique to quantify PG content in normal and experimentally

Contrast agent enhanced pQCT of articular cartilage

Science.gov (United States)

Kallioniemi, A. S.; Jurvelin, J. S.; Nieminen, M. T.; Lammi, M. J.; Töyräs, J.

2007-02-01

The delayed gadolinium enhanced MRI of cartilage (dGEMRIC) technique is the only non-invasive means to estimate proteoglycan (PG) content in articular cartilage. In dGEMRIC, the anionic paramagnetic contrast agent gadopentetate distributes in inverse relation to negatively charged PGs, leading to a linear relation between T1,Gd and spatial PG content in tissue. In the present study, for the first time, contrast agent enhanced peripheral quantitative computed tomography (pQCT) was applied, analogously to dGEMRIC, for the quantitative detection of spatial PG content in cartilage. The suitability of two anionic radiographic contrast agents, gadopentetate and ioxaglate, to detect enzymatically induced PG depletion in articular cartilage was investigated. First, the interrelationships of x-ray absorption, as measured with pQCT, and the contrast agent solution concentration were investigated. Optimal contrast agent concentrations for the following experiments were selected. Second, diffusion rates for both contrast agents were investigated in intact (n = 3) and trypsin-degraded (n = 3) bovine patellar cartilage. The contrast agent concentration of the cartilaginous layer was measured prior to and 2-27 h after immersion. Optimal immersion time for the further experiments was selected. Third, the suitability of gadopentetate and ioxaglate enhanced pQCT to detect the enzymatically induced specific PG depletion was investigated by determining the contrast agent concentrations and uronic acid and water contents in digested and intact osteochondral samples (n = 16). After trypsin-induced PG loss (-70%, p < 0.05) the penetration of gadopentetate and ioxaglate increased (p < 0.05) by 34% and 48%, respectively. Gadopentetate and ioxaglate concentrations both showed strong correlation (r = -0.95, r = -0.94, p < 0.01, respectively) with the uronic acid content. To conclude, contrast agent enhanced pQCT provides a technique to quantify PG content in normal and experimentally

Contrast agent enhanced pQCT of articular cartilage

International Nuclear Information System (INIS)

Kallioniemi, A S; Jurvelin, J S; Nieminen, M T; Lammi, M J; Toeyraes, J

2007-01-01

The delayed gadolinium enhanced MRI of cartilage (dGEMRIC) technique is the only non-invasive means to estimate proteoglycan (PG) content in articular cartilage. In dGEMRIC, the anionic paramagnetic contrast agent gadopentetate distributes in inverse relation to negatively charged PGs, leading to a linear relation between T 1,Gd and spatial PG content in tissue. In the present study, for the first time, contrast agent enhanced peripheral quantitative computed tomography (pQCT) was applied, analogously to dGEMRIC, for the quantitative detection of spatial PG content in cartilage. The suitability of two anionic radiographic contrast agents, gadopentetate and ioxaglate, to detect enzymatically induced PG depletion in articular cartilage was investigated. First, the interrelationships of x-ray absorption, as measured with pQCT, and the contrast agent solution concentration were investigated. Optimal contrast agent concentrations for the following experiments were selected. Second, diffusion rates for both contrast agents were investigated in intact (n = 3) and trypsin-degraded (n 3) bovine patellar cartilage. The contrast agent concentration of the cartilaginous layer was measured prior to and 2-27 h after immersion. Optimal immersion time for the further experiments was selected. Third, the suitability of gadopentetate and ioxaglate enhanced pQCT to detect the enzymatically induced specific PG depletion was investigated by determining the contrast agent concentrations and uronic acid and water contents in digested and intact osteochondral samples (n = 16). After trypsin-induced PG loss (-70%, p < 0.05) the penetration of gadopentetate and ioxaglate increased (p < 0.05) by 34% and 48%, respectively. Gadopentetate and ioxaglate concentrations both showed strong correlation (r = -0.95, r -0.94, p < 0.01, respectively) with the uronic acid content. To conclude, contrast agent enhanced pQCT provides a technique to quantify PG content in normal and experimentally degraded

Research on e-commerce transaction networks using multi-agent modelling and open application programming interface

Science.gov (United States)

Piao, Chunhui; Han, Xufang; Wu, Harris

2010-08-01

We provide a formal definition of an e-commerce transaction network. Agent-based modelling is used to simulate e-commerce transaction networks. For real-world analysis, we studied the open application programming interfaces (APIs) from eBay and Taobao e-commerce websites and captured real transaction data. Pajek is used to visualise the agent relationships in the transaction network. We derived one-mode networks from the transaction network and analysed them using degree and betweenness centrality. Integrating multi-agent modelling, open APIs and social network analysis, we propose a new way to study large-scale e-commerce systems.

Inhibitory effect of indole analogs against Paenibacillus larvae, the causal agent of American foulbrood disease.

Science.gov (United States)

Alvarado, Israel; Margotta, Joseph W; Aoki, Mai M; Flores, Fernando; Agudelo, Fresia; Michel, Guillermo; Elekonich, Michelle M; Abel-Santos, Ernesto

2017-09-01

Paenibacillus larvae, a Gram-positive bacterium, causes American foulbrood (AFB) in honey bee larvae (Apis mellifera Linnaeus [Hymenoptera: Apidae]). P. larvae spores exit dormancy in the gut of bee larvae, the germinated cells proliferate, and ultimately bacteremia kills the host. Hence, spore germination is a required step for establishing AFB disease. We previously found that P. larvae spores germinate in response to l-tyrosine plus uric acid in vitro. Additionally, we determined that indole and phenol blocked spore germination. In this work, we evaluated the antagonistic effect of 35 indole and phenol analogs and identified strong inhibitors of P. larvae spore germination in vitro. We further tested the most promising candidate, 5-chloroindole, and found that it significantly reduced bacterial proliferation. Finally, feeding artificial worker jelly containing anti-germination compounds to AFB-exposed larvae significantly decreased AFB infection in laboratory-reared honey bee larvae. Together, these results suggest that inhibitors of P. larvae spore germination could provide another method to control AFB. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America.

Analogical Reasoning in the Engineering Design Process and Technology Education Applications

OpenAIRE

2008-01-01

This synthesis paper discusses the research exploring analogical reasoning, the role of analogies in the engineering design process, and educational applications for analogical reasoning. Researchers have discovered that analogical reasoning is often a fundamental cognitive tool in design problem solving. Regarding the possible role of analogical reasoning in the context of technology education; analogies may be a useful tool to develop student’s design skills, teach abstract or complex conce...

Capturing Thoughts, Capturing Minds?

DEFF Research Database (Denmark)

Nielsen, Janni

2004-01-01

Think Aloud is cost effective, promises access to the user's mind and is the applied usability technique. But 'keep talking' is difficult, besides, the multimodal interface is visual not verbal. Eye-tracking seems to get around the verbalisation problem. It captures the visual focus of attention...

An Analog Computer for Electronic Engineering Education

Science.gov (United States)

Fitch, A. L.; Iu, H. H. C.; Lu, D. D. C.

2011-01-01

This paper describes a compact analog computer and proposes its use in electronic engineering teaching laboratories to develop student understanding of applications in analog electronics, electronic components, engineering mathematics, control engineering, safe laboratory and workshop practices, circuit construction, testing, and maintenance. The…

The interplay of conflict and analogy in multidisciplinary teams.

Science.gov (United States)

Paletz, Susannah B F; Schunn, Christian D; Kim, Kevin H

2013-01-01

Creative teamwork in multidisciplinary teams is a topic of interest to cognitive psychologists on the one hand, and to both social and organizational psychologists on the other. However, the interconnections between cognitive and social layers have been rarely explored. Drawing on mental models and dissonance theories, the current study takes a central variable studied by cognitive psychologists-analogy-and examines its relationship to a central variable examined by social psychologists-conflict. In an observational, field study, over 11h of audio-video data from conversations of the Mars Exploration Rover scientists were coded for different types of analogy and micro-conflicts that reveal the character of underlying psychological mechanisms. Two different types of time-lagged logistic models applied to these data revealed asymmetric patterns of associations between analogy and conflict. Within-domain analogies, but not within-discipline or outside-discipline analogies, preceded science and work process conflicts, suggesting that in multidisciplinary teams, representational gaps in very close domains will be more likely to spark conflict. But analogies also occurred in reaction to conflict: Process and negative conflicts, but not task conflicts, preceded within-discipline analogies, but not to within-domain or outside-discipline analogies. This study demonstrates ways in which cognition can be bidirectionally tied to social processes and discourse. Copyright © 2012 Elsevier B.V. All rights reserved.

Monoketone analogs of curcumin, a new class of Fanconi anemia pathway inhibitors

Directory of Open Access Journals (Sweden)

Turker Mitchell S

2009-12-01

Full Text Available Abstract Background The Fanconi anemia (FA pathway is a multigene DNA damage response network implicated in the repair of DNA lesions that arise during replication or after exogenous DNA damage. The FA pathway displays synthetic lethal relationship with certain DNA repair genes such as ATM (Ataxia Telangectasia Mutated that are frequently mutated in tumors. Thus, inhibition of FANCD2 monoubiquitylation (FANCD2-Ub, a key step in the FA pathway, might target tumor cells defective in ATM through synthetic lethal interaction. Curcumin was previously identified as a weak inhibitor of FANCD2-Ub. The aim of this study is to identify derivatives of curcumin with better activity and specificity. Results Using a replication-free assay in Xenopus extracts, we screened monoketone analogs of curcumin for inhibition of FANCD2-Ub and identified analog EF24 as a strong inhibitor. Mechanistic studies suggest that EF24 targets the FA pathway through inhibition of the NF-kB pathway kinase IKK. In HeLa cells, nanomolar concentrations of EF24 inhibited hydroxyurea (HU-induced FANCD2-Ub and foci in a cell-cycle independent manner. Survival assays revealed that EF24 specifically sensitizes FA-competent cells to the DNA crosslinking agent mitomycin C (MMC. In addition, in contrast with curcumin, ATM-deficient cells are twofold more sensitive to EF24 than matched wild-type cells, consistent with a synthetic lethal effect between FA pathway inhibition and ATM deficiency. An independent screen identified 4H-TTD, a compound structurally related to EF24 that displays similar activity in egg extracts and in cells. Conclusions These results suggest that monoketone analogs of curcumin are potent inhibitors of the FA pathway and constitute a promising new class of targeted anticancer compounds.

Fluorinated analogs of malachite green: synthesis and toxicity.

Science.gov (United States)

Kraus, George A; Jeon, Insik; Nilsen-Hamilton, Marit; Awad, Ahmed M; Banerjee, Jayeeta; Parvin, Bahram

2008-04-27

A series of fluorinated analogs of malachite green (MG) have been synthesized and their toxicity to Saccharomyces cerevisiae and a human ovarian epithelial cell line examined. The toxicity profiles were found to be different for these two species. Two analogs, one with 2,4-difluoro substitution and the other with 2-fluoro substitution seem to be the most promising analogs because they showed the lowest toxicity to the human cells.

Analogies between classical statistical mechanics and quantum mechanics

International Nuclear Information System (INIS)

Uehara, M.

1986-01-01

Some analogies between nonequilibrium classical statistical mechanics and quantum mechanics, at the level of the Liouville equation and at the kinetic level, are commented on. A theorem, related to the Vlasov equation applied to a plasma, is proved. The theorem presents an analogy with Ehrenfest's theorem of quantum mechanics. An analogy between the plasma kinetic theory and Bohm's quantum theory with 'hidden variables' is also shown. (Author) [pt

Tracking cognitive phases in analogical reasoning with event-related potentials.

Science.gov (United States)

Maguire, Mandy J; McClelland, M Michelle; Donovan, Colin M; Tillman, Gail D; Krawczyk, Daniel C

2012-03-01

Analogical reasoning consists of multiple phases. Four-term analogies (A:B::C:D) have an encoding period in which the A:B pair is evaluated prior to a mapping phase. The electrophysiological timing associated with analogical reasoning has remained unclear. We used event-related potentials to identify neural timing related to analogical reasoning relative to perceptual and semantic control conditions. Spatiotemporal principal-components analyses revealed differences primarily in left frontal electrodes during encoding and mapping phases of analogies relative to the other conditions. The timing of the activity differed depending upon the phase of the problem. During the encoding of A:B terms, analogies elicited a positive deflection compared to the control conditions between 400 and 1,200 ms, but for the mapping phase analogical processing elicited a negative deflection that occurred earlier and for a shorter time period, between 350 and 625 ms. These results provide neural and behavioral evidence that 4-term analogy problems involve a highly active evaluation phase of the A:B pair. 2012 APA, all rights reserved

High-frequency analog integrated circuit design

CERN Document Server

1995-01-01

To learn more about designing analog integrated circuits (ICs) at microwave frequencies using GaAs materials, turn to this text and reference. It addresses GaAs MESFET-based IC processing. Describes the newfound ability to apply silicon analog design techniques to reliable GaAs materials and devices which, until now, was only available through technical papers scattered throughout hundred of articles in dozens of professional journals.

HAPS, a Handy Analog Programming System

DEFF Research Database (Denmark)

Højberg, Kristian Søe

1975-01-01

HAPS (Hybrid Analog Programming System) is an analog compiler that can be run on a minicomputer in an interactive mode. Essentially HAPS is written in FORTRAN. The equations to be programmed for an ana log computer are read in by using a FORTRAN-like notation. The input must contain maximum...... and emphasizes the limitations HAPS puts on equation structure, types of computing circuit, scaling, and static testing....

Testing of selected pharmacological agents for capturing waterfowl [Annual Progress Report

Science.gov (United States)

Cline, D.R.

1970-01-01

The response of game-farm mallards (Frost strain) to seven pharmacological immobilizing agents was evaluated in Phase I of a planned four-phase study. A limited amount of testing was also done with wild mallards. Single dosages were administered to determine the mean effective dose (ED50) and mean lethal dose (LD50), The therapeutic index, or safety factor (LD50/ED50), and palatability were also established. Optimum dosage rates of compounds administered orally on baits were not considered in this phase of the study. Compounds were-administered by intubation and calculated in terms of mg/kg. All except one compound produced narcosis within 5 minutes at the effective dose rate.Immobilization periods for the seven compounds ranged from 7-24 minutes, and recovery periods from 1.0-6.5 hours. Such wide variations in actions of the compounds can be attributed to a compound's rate of absorption, the ease with which it passes the blood-brain barrier, its solubility in tissues, and its rate of metabolism in the liver and kidneys. Length of both the immobilization and recovery periods were extended when dosages were increased. There was no delayed mortality among survivors with any of the seven compounds at either the ED50 or LD50. Females were generally more sensitive to the anesthetizing agents than males. The ED50 for wild mallards was substantially higher than that for the experimental game-farm birds for the two compounds on which this was tested.Tribromoethanol (Avertin of Winthrop Laboratories) satisfied all test criteria an Phase I and will be subjected to more intensive investigation in ensuing tests. Thiopental sodium (Pentothal of Amdal Company) and pentobarbital sodium (Nembutal of Abbott Laboratories) were judged to be marginal. Although their therapeutic indexes were good (5.00), recovery periods were prolonged and toxic convulsions occurred at medium to high dose rates as the LD50 was approached.Alpha-chloralose (Fisher Scientific) proved least promising of

The use of analogy in pro-life argumentation

Directory of Open Access Journals (Sweden)

Simona Mazilu

2012-11-01

Full Text Available The paper is concerned with how analogy is strategically used in pro-life argumentation on abortion. Pragma-dialectics (van Eemeren and Grootendorst 1992 offers a set of critical questions by means of which I will evaluate the use of the argumentation based on a relation of analogy in terms of dialectical soundness. Examining various pro-life texts, I have noticed that the analogies employed remain unexplained. Therefore, despite the apparent similarities between abortion and the German holocaust or slavery, for instance, there are essential differences which are not mentioned. I claim that these analogies mainly have a rhetorical function, to operate what has been called by Micheli (2007: 960 “a transfer of emotional consensus”.

Patterns of Analogical Reasoning among Beginning Readers

Science.gov (United States)

Farrington-Flint, Lee; Wood, Clare; Canobi, Katherine H.; Faulkner, Dorothy

2004-01-01

Despite compelling evidence that analogy skills are available to beginning readers, few studies have actually explored the possibility of identifying individual differences in young children's analogy skills in early reading. The present study examined individual differences in children's use of orthographic and phonological relations between…

Single-event transients (SET) in analog circuits

International Nuclear Information System (INIS)

Chen Panxun; Zhou Kaiming

2006-01-01

A new phenomenon of single- event upset is introduced. The transient signal is produced in the output of analog circuits after a heavy ion strikes. The transient upset can influence the circuit connected with the output of analog circuits. For example, the output of operational amplifier can be connected with the input of a digital counter, and the pulse of sufficiently high transient output induced by an ion can increase counts of the counter. On the other hand, the transient voltage signal at the output of analog circuits can change the stage of other circuits. (authors)

From actors to agents in socio-ecological systems models.

Science.gov (United States)

Rounsevell, M D A; Robinson, D T; Murray-Rust, D

2012-01-19

The ecosystem service concept has emphasized the role of people within socio-ecological systems (SESs). In this paper, we review and discuss alternative ways of representing people, their behaviour and decision-making processes in SES models using an agent-based modelling (ABM) approach. We also explore how ABM can be empirically grounded using information from social survey. The capacity for ABM to be generalized beyond case studies represents a crucial next step in modelling SESs, although this comes with considerable intellectual challenges. We propose the notion of human functional types, as an analogy of plant functional types, to support the expansion (scaling) of ABM to larger areas. The expansion of scope also implies the need to represent institutional agents in SES models in order to account for alternative governance structures and policy feedbacks. Further development in the coupling of human-environment systems would contribute considerably to better application and use of the ecosystem service concept.

An analog silicon retina with multichip configuration.

Science.gov (United States)

Kameda, Seiji; Yagi, Tetsuya

2006-01-01

The neuromorphic silicon retina is a novel analog very large scale integrated circuit that emulates the structure and the function of the retinal neuronal circuit. We fabricated a neuromorphic silicon retina, in which sample/hold circuits were embedded to generate fluctuation-suppressed outputs in the previous study [1]. The applications of this silicon retina, however, are limited because of a low spatial resolution and computational variability. In this paper, we have fabricated a multichip silicon retina in which the functional network circuits are divided into two chips: the photoreceptor network chip (P chip) and the horizontal cell network chip (H chip). The output images of the P chip are transferred to the H chip with analog voltages through the line-parallel transfer bus. The sample/hold circuits embedded in the P and H chips compensate for the pattern noise generated on the circuits, including the analog communication pathway. Using the multichip silicon retina together with an off-chip differential amplifier, spatial filtering of the image with an odd- and an even-symmetric orientation selective receptive fields was carried out in real time. The analog data transfer method in the present multichip silicon retina is useful to design analog neuromorphic multichip systems that mimic the hierarchical structure of neuronal networks in the visual system.

Reynolds analogy for the Rayleigh problem at various flow modes.

Science.gov (United States)

Abramov, A A; Butkovskii, A V

2016-07-01

The Reynolds analogy and the extended Reynolds analogy for the Rayleigh problem are considered. For a viscous incompressible fluid we derive the Reynolds analogy as a function of the Prandtl number and the Eckert number. We show that for any positive Eckert number, the Reynolds analogy as a function of the Prandtl number has a maximum. For a monatomic gas in the transitional flow regime, using the direct simulation Monte Carlo method, we investigate the extended Reynolds analogy, i.e., the relation between the shear stress and the energy flux transferred to the boundary surface, at different velocities and temperatures. We find that the extended Reynolds analogy for a rarefied monatomic gas flow with the temperature of the undisturbed gas equal to the surface temperature depends weakly on time and is close to 0.5. We show that at any fixed dimensionless time the extended Reynolds analogy depends on the plate velocity and temperature and undisturbed gas temperature mainly via the Eckert number. For Eckert numbers of the order of unity or less we generalize an extended Reynolds analogy. The generalized Reynolds analogy depends mainly only on dimensionless time for all considered Eckert numbers of the order of unity or less.

Two analogy strategies: the cases of mind metaphors and introspection

Science.gov (United States)

Fischer, Eugen

2018-04-01

Analogical reasoning is often employed in problem-solving and metaphor interpretation. This paper submits that, as a default, analogical reasoning addressing these different tasks employs different mapping strategies. In problem-solving, it employs analogy-maximising strategies (like structure mapping, Gentner, D., & Markman, A. B. (1997). Structure mapping in analogy and similarity. American Psychologist, 52, 45-56); in metaphor interpretation, analogy-minimising strategies (like ATT-Meta, Barnden, J. A. (2015). Open-ended elaborations in creative metaphor. In T. R. Besold, M. Schorlemmer, & A. Smaill (Eds.), Computational creativity research: Towards creative machines (pp. 217-242). Berlin: Springer). The two strategies interact in analogical reasoning with conceptual metaphors. This interaction leads to predictable fallacies. The paper supports these hypotheses through case-studies on "mind" metaphors from ordinary discourse, and abstract problem-solving in the philosophy of mind, respectively. It shows that (1) default metaphorical interpretations for vision- and space-cognition metaphors can be derived with a variant of the analogy-minimising ATT-Meta approach, (2) philosophically influential introspective conceptions of the mind can be derived with conceptual metaphors only through an analogy-maximising strategy, and (3) the interaction of these strategies leads to hitherto unrecognised fallacies in analogical reasoning with metaphors. This yields a debunking explanation of introspective conceptions.

25th workshop on Advances in Analog Circuit Design

CERN Document Server

Harpe, Pieter; Makinwa, Kofi

2017-01-01

This book is based on the 18 tutorials presented during the 25th workshop on Advances in Analog Circuit Design. Expert designers present readers with information about a variety of topics at the frontier of analog circuit design, including low-power and energy-efficient analog electronics, with specific contributions focusing on the design of continuous-time sigma-delta modulators, automotive electronics, and power management. This book serves as a valuable reference to the state-of-the-art, for anyone involved in analog circuit research and development.

Is the Link from Working Memory to Analogy Causal? No Analogy Improvements following Working Memory Training Gains

OpenAIRE

Richey, J. Elizabeth; Phillips, Jeffrey S.; Schunn, Christian D.; Schneider, Walter

2014-01-01

Analogical reasoning has been hypothesized to critically depend upon working memory through correlational data [1], but less work has tested this relationship through experimental manipulation [2]. An opportunity for examining the connection between working memory and analogical reasoning has emerged from the growing, although somewhat controversial, body of literature suggests complex working memory training can sometimes lead to working memory improvements that transfer to novel working mem...

Selective termination, fetal reduction and analogical reasoning.

Science.gov (United States)

Pennings, G

2013-06-01

Analogical reasoning is a basic method in bioethics. Its main purpose is to transfer the rule from an existing or known situation to a new and problematic situation. This commentary applies the lifeboat analogy to the context of selective termination and fetal reduction. It turns out that the analogy is only partially helpful as the main principle in the case of selective termination is the procreative beneficence principle. However, the wide person-affecting form of this principle doubly justifies selective termination: i.e. one prevents the harm caused by the birth of an affected child and one increases the life chances of the remaining fetuses. I conclude, however, that all analogies are basically flawed since they assume that fetuses as such have interests. I argue that fetuses only have interests to the extent that they are potential future persons. Copyright © 2013 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.

The design analogy : a model for moral problem solving

NARCIS (Netherlands)

Dorst, C.H.; Royakkers, L.M.M.

2006-01-01

In this paper we explore an analogy between design and ethics, first drawn by Whitbeck. We investigate her claim that such an analogy can help to understand moral problems and aid us in dealing with them by suggesting strategies for addressing moral problems. We explore the nature of analogies, and

Wafer-level chip-scale packaging analog and power semiconductor applications

CERN Document Server

Qu, Shichun

2015-01-01

This book presents a state-of-art and in-depth overview in analog and power WLCSP design, material characterization, reliability, and modeling. Recent advances in analog and power electronic WLCSP packaging are presented based on the development of analog technology and power device integration. The book covers in detail how advances in semiconductor content, analog and power advanced WLCSP design, assembly, materials, and reliability have co-enabled significant advances in fan-in and fan-out with redistributed layer (RDL) of analog and power device capability during recent years. Along with new analog and power WLCSP development, the role of modeling is a key to assure successful package design. An overview of the analog and power WLCSP modeling and typical thermal, electrical, and stress modeling methodologies is also provided. This book also: ·         Covers the development of wafer-level power discrete packaging with regular wafer-level design concepts and directly bumping technology ·    �...

Modern Communication: Exploring Physiological Transmission through Tech-Savvy Analogies

Science.gov (United States)

Hollabaugh, Christopher R.; Milanick, Mark A.

2014-01-01

Analogies are often helpful for students to grasp key physiological concepts; sometimes the technical jargon makes the concept seem more complex than it actually is. In this article the authors provide several analogies for information transfer processes that sometimes confuse students. For an analogy to be useful, of course, it needs to be…

AnalogRF and mixed-signal circuit systematic design

CERN Document Server

Tlelo-Cuautle, Esteban; Castro-Lopez, Rafael

2013-01-01

Despite the fact that in the digital domain, designers can take full benefits of IPs and design automation tools to synthesize and design very complex systems, the analog designers’ task is still considered as a ‘handcraft’, cumbersome and very time consuming process. Thus, tremendous efforts are being deployed  to develop new design methodologies in the analog/RF and mixed-signal domains. This book collects 16 state-of-the-art contributions devoted to the topic of systematic design of analog, RF and mixed signal circuits. Divided in the two parts Methodologies and Techniques recent theories, synthesis techniques and design methodologies, as well as new sizing approaches in the field of robust analog and mixed signal design automation are presented for researchers and R/D engineers.  

Agentes farmacológicos actuales en el tratamiento de la diabetes mellitus no insulinodependiente

Directory of Open Access Journals (Sweden)

Arturo Hernández-Yero

1997-12-01

thiazolidinediones, whose used at the beginning of the disease or in insulin-resistant patients may delay or prevent the development of the disease, and may interfere in the progressive reduction of the pancreatic function. An important group of pharmacological agents, as well as their possible mechanisms of action, which have been investigated, are shown to widen and increase the therapeutics of diabetes. The insuline analogs, the insulinomimetic agents, and the oral insuline preparations, the non-sulphonylurea insulinotropic agents, the amylene analogs, the peptides similar to glucagon, the adrenergic alpha-2 antagonist, the modulators of glucose metabolism, and some substances of vegetal origin with possible hypoglycaemic effects, are among these agents

Proportional and functional analogical reasoning in normal and language-impaired children.

Science.gov (United States)

Nippold, M A; Erskine, B J; Freed, D B

1988-11-01

Teachers often use analogies in classroom settings to clarify new concepts for their students. However, analogies may inadvertently confuse the youngster who has difficulty identifying the one-to-one comparisons underlying them. Although analogical reasoning has been studied extensively in normal children, no information was available concerning this construct in children having a specific language impairment. Thus, it was unknown to what extent they might be deficient in analogical reasoning. Therefore, in the present study, 20 children ages 6-8 years (mean age = 7:6) having normal nonverbal intelligence but deficits in language comprehension were administered tasks of verbal and perceptual proportional analogical reasoning and a problem-solving task of functional analogical reasoning. Compared to a normal-language control group matched on the basis of chronological age and sex, the language-impaired group was deficient in all three tasks of analogical reasoning. However, when the factor of nonverbal intelligence was controlled statistically, the differences between the groups on each of the tasks were removed. Additional findings were that verbal proportional analogical reasoning was significantly correlated to perceptual proportional analogical reasoning and to functional analogical reasoning. Implications for assessment and intervention with young school-age language-impaired children are discussed.

Perspectives on New Synthetic Curcumin Analogs and their Potential Anticancer Properties

Science.gov (United States)

Vyas, Alok; Dandawate, Prasad; Padhye, Subhash; Ahmad, Aamir; Sarkar, Fazlul

2013-01-01

Curcumin is the active component of dried rhizome of Curcuma longa, a perennial herb belonging to ginger family, cultivated extensively in south and southeastern tropical Asia. It is widely consumed in the Indian subcontinent, south Asia and Japan in traditional food recipes. Extensive research over last few decades has shown that curcumin is a potent anti-inflammatory agent with powerful therapeutic potential against a variety of cancers. It suppresses proliferation and metastasis of human tumors through regulation of various transcription factors, growth factors, inflammatory cytokines, protein kinases and other enzymes. It induces apoptotic cell death and also inhibits proliferation of cancer cells by cell cycle arrest. Pharmacokinetic data has shown that curcumin undergoes rapid metabolism leading to glucuronidation and sulfation in the liver and excretion in the feces, which accounts for its poor systemic bioavailability. The compound has, therefore, been formulated and administered using different drug delivery systems such as liposomes, micelles, polysaccharides, phospholipid complexes and nanoparticles that can overcome the limitation of bioavailability to some extent. Attempts to avoid rapid metabolism of curcumin until now have been met with limited success. This has prompted researchers to look for new synthetic curcumin analogs in order to overcome the drawbacks of limited bioavailability and rapid metabolism, and gain efficacy with reduced toxicity. In this review we provide a summarized account of novel synthetic curcumin formulations and analogs, and the recent progress in the field of cancer prevention and treatment. PMID:23116312

Analogical reasoning and aging: the processing speed and inhibition hypothesis.

Science.gov (United States)

Bugaiska, Aurélia; Thibaut, Jean-Pierre

2015-01-01

This study was designed to investigate the effect of aging on analogical reasoning by manipulating the strength of semantic association (LowAssoc or HighAssoc) and the number of distracters' semantic analogies of the A:B::C:D type and to determine which factors might be responsible for the age-related differences on analogical reasoning by testing two different theoretical frameworks: the inhibition hypothesis and the speed mediation hypothesis. We compared young adults and two groups of aging people (old and old-old) with word analogies of the A:B::C:D format. Results indicate an age-related effect on analogical reasoning, this effect being greatest with LowAssoc analogies. It was not associated with the presence of semantic distractors. Moreover, the results show that the variance part of the analogy task due to age was mainly explained by processing speed (rather than by inhibition) in the case of old participants and by both processing speed and inhibition in the old-old group. These results are discussed in relation to current models of aging and their interaction with the processes involved in analogical reasoning.

Analogy as a means of theoretical adoption of pedagogical disciplines

Directory of Open Access Journals (Sweden)

Solovcova Irina A.

2006-01-01

Full Text Available The paper considers an application of analogy in the initial-teacher training as a tool of approaching pedagogical disciplines. The author proposes a classification of pedagogical analogies which provides choices of the most efficient model for a specific didactic situation. The article clarifies the model of the theoretical approach to pedagogical disciplines through active use of analogy, which contributes to a higher efficiency in a teacher and student interaction. The model consists of three stages: training (the stage of acquiring analogy model, the analytical stage (acquisition of pedagogical concepts, phenomena and systems through the application of analogy, and the stage of self-realization (the application of analogy method in students’ scientific-research activities considering external and internal didactic conditions which transform analogy from a teaching method into a tool for the acquisition of pedagogical disciplines. The author demonstrates that the application of analogy has a positive effect not only on the acquisition of pedagogical knowledge (especially methodic and the development of heuristic skills in students, but also on motivation for the study of pedagogical disciplines (cognitive aspect and professional pedagogical activity (formation of an individual-pedagogical attitude. .

Carbon captured from the air

International Nuclear Information System (INIS)

Keith, D.

2008-01-01

This article presented an innovative way to achieve the efficient capture of atmospheric carbon. A team of scientists from the University of Calgary's Institute for Sustainable Energy, Environment and Economy have shown that it is possible to reduce carbon dioxide (CO 2 ) using a simple machine that can capture the trace amount of CO 2 present in ambient air at any place on the planet. The thermodynamics of capturing the small concentrations of CO 2 from the air is only slightly more difficult than capturing much larger concentrations of CO 2 from power plants. The research is significant because it offers a way to capture CO 2 emissions from transportation sources such as vehicles and airplanes, which represent more than half of the greenhouse gases emitted on Earth. The energy efficient and cost effective air capture technology could complement other approaches for reducing emissions from the transportation sector, such as biofuels and electric vehicles. Air capture differs from carbon capture and storage (CCS) technology used at coal-fired power plants where CO 2 is captured and pipelined for permanent storage underground. Air capture can capture the CO 2 that is present in ambient air and store it wherever it is cheapest. The team at the University of Calgary showed that CO 2 could be captured directly from the air with less than 100 kWhrs of electricity per tonne of CO 2 . A custom-built tower was able to capture the equivalent of 20 tonnes per year of CO 2 on a single square meter of scrubbing material. The team devised a way to use a chemical process from the pulp and paper industry to cut the energy cost of air capture in half. Although the technology is only in its early stage, it appears that CO 2 could be captured from the air with an energy demand comparable to that needed for CO 2 capture from conventional power plants, but costs will be higher. The simple, reliable and scalable technology offers an opportunity to build a commercial-scale plant. 1 fig

Capture by colour: evidence for dimension-specific singleton capture.

Science.gov (United States)

Harris, Anthony M; Becker, Stefanie I; Remington, Roger W

2015-10-01

Previous work on attentional capture has shown the attentional system to be quite flexible in the stimulus properties it can be set to respond to. Several different attentional "modes" have been identified. Feature search mode allows attention to be set for specific features of a target (e.g., red). Singleton detection mode sets attention to respond to any discrepant item ("singleton") in the display. Relational search sets attention for the relative properties of the target in relation to the distractors (e.g., redder, larger). Recently, a new attentional mode was proposed that sets attention to respond to any singleton within a particular feature dimension (e.g., colour; Folk & Anderson, 2010). We tested this proposal against the predictions of previously established attentional modes. In a spatial cueing paradigm, participants searched for a colour target that was randomly either red or green. The nature of the attentional control setting was probed by presenting an irrelevant singleton cue prior to the target display and assessing whether it attracted attention. In all experiments, the cues were red, green, blue, or a white stimulus rapidly rotated (motion cue). The results of three experiments support the existence of a "colour singleton set," finding that all colour cues captured attention strongly, while motion cues captured attention only weakly or not at all. Notably, we also found that capture by motion cues in search for colour targets was moderated by their frequency; rare motion cues captured attention (weakly), while frequent motion cues did not.

Materials For Gas Capture, Methods Of Making Materials For Gas Capture, And Methods Of Capturing Gas

KAUST Repository

Polshettiwar, Vivek

2013-06-20

In accordance with the purpose(s) of the present disclosure, as embodied and broadly described herein, embodiments of the present disclosure, in one aspect, relate to materials that can be used for gas (e.g., CO.sub.2) capture, methods of making materials, methods of capturing gas (e.g., CO.sub.2), and the like, and the like.

Synthetic Biology: A Unifying View and Review Using Analog Circuits.

Science.gov (United States)

Teo, Jonathan J Y; Woo, Sung Sik; Sarpeshkar, Rahul

2015-08-01

We review the field of synthetic biology from an analog circuits and analog computation perspective, focusing on circuits that have been built in living cells. This perspective is well suited to pictorially, symbolically, and quantitatively representing the nonlinear, dynamic, and stochastic (noisy) ordinary and partial differential equations that rigorously describe the molecular circuits of synthetic biology. This perspective enables us to construct a canonical analog circuit schematic that helps unify and review the operation of many fundamental circuits that have been built in synthetic biology at the DNA, RNA, protein, and small-molecule levels over nearly two decades. We review 17 circuits in the literature as particular examples of feedforward and feedback analog circuits that arise from special topological cases of the canonical analog circuit schematic. Digital circuit operation of these circuits represents a special case of saturated analog circuit behavior and is automatically incorporated as well. Many issues that have prevented synthetic biology from scaling are naturally represented in analog circuit schematics. Furthermore, the deep similarity between the Boltzmann thermodynamic equations that describe noisy electronic current flow in subthreshold transistors and noisy molecular flux in biochemical reactions has helped map analog circuit motifs in electronics to analog circuit motifs in cells and vice versa via a `cytomorphic' approach. Thus, a body of knowledge in analog electronic circuit design, analysis, simulation, and implementation may also be useful in the robust and efficient design of molecular circuits in synthetic biology, helping it to scale to more complex circuits in the future.

Abstract analogical reasoning in high-functioning children with autism spectrum disorders.

Science.gov (United States)

Green, Adam E; Kenworthy, Lauren; Mosner, Maya G; Gallagher, Natalie M; Fearon, Edward W; Balhana, Carlos D; Yerys, Benjamin E

2014-12-01

Children with autism spectrum disorders (ASD) exhibit a deficit in spontaneously recognizing abstract similarities that are crucial for generalizing learning to new situations. This may contribute to deficits in the development of appropriate schemas for navigating novel situations, including social interactions. Analogical reasoning is the central cognitive mechanism that enables typically developing children to understand abstract similarities between different situations. Intriguingly, studies of high-functioning children with ASD point to a relative cognitive strength in basic, nonabstract forms of analogical reasoning. If this analogical reasoning ability extends to abstract analogical reasoning (i.e., between superficially dissimilar situations), it may provide a bridge between a cognitive capability and core ASD deficits in areas such as generalization and categorization. This study tested whether preserved analogical reasoning abilities in ASD can be extended to abstract analogical reasoning, using photographs of real-world items and situations. Abstractness of the analogies was determined via a quantitative measure of semantic distance derived from latent semantic analysis. Children with ASD performed as well as typically developing children at identifying abstract analogical similarities when explicitly instructed to apply analogical reasoning. Individual differences in abstract analogical reasoning ability predicted individual differences in a measure of social function in the ASD group. Preliminary analyses indicated that children with ASD, but not typically developing children, showed an effect of age on abstract analogical reasoning. These results provide new evidence that children with ASD are capable of identifying abstract similarities through analogical reasoning, pointing to abstract analogical reasoning as a potential lever for improving generalization skills and social function in ASD. © 2014 International Society for Autism Research, Wiley

Quantum Analog Computing

Science.gov (United States)

Zak, M.

1998-01-01

Quantum analog computing is based upon similarity between mathematical formalism of quantum mechanics and phenomena to be computed. It exploits a dynamical convergence of several competing phenomena to an attractor which can represent an externum of a function, an image, a solution to a system of ODE, or a stochastic process.

Changes in analogical reasoning in adulthood.

Science.gov (United States)

Clark, E; Gardner, M K; Brown, G; Howell, R J

1990-01-01

This study sought to investigate adult intellectual development through an analysis of a particular type of cognitive ability, verbal analogical reasoning. The performance of 60 individuals between the ages of 20 and 79 was compared on 100 verbal analogies. The subjects consisted of six groups of ten individuals each (five males and five females), matched as a group for education and gender. Solution times and error rates served as the dependent measures. Results showed that there was a significant trend for the older subjects (60- and 70-year-olds) to be slower than the young subjects (20-, 30-, 40-, and 50-year-olds), but not necessarily more error prone. These data suggest that verbal analogical reasoning changes with age. Supplemental data demonstrated a change in other abilities as well (i.e., decline in perceptual-motor speed and spatial skill).

Electrical analog of a Josephson junction

International Nuclear Information System (INIS)

Goldman, A.M.

1979-01-01

It is noted that a mathematical description of the phase-coupling of two oscillators synchronized by a phase-lock-loop under the influence of thermal white noise is analogous to that of the phase coupling of two superconductors in a Josephson junction also under the influence of noise. This analogy may be useful in studying threshold instabilities of the Josephson junction in regimes not restricted to the case of large damping. This is of interest because the behavior of the mean voltage near the threshold current can be characterized by critical exponents which resemble those exhibited by an order parameter of a continuous phase transition. As it is possible to couple a collection of oscillators together in a chain, the oscillator analogy may also be useful in exploring the dynamics and statistical mechanics of coupled junctions

Design, synthesis and development of novel indolocarbazole derivatives as potential anti-cancer agents

OpenAIRE

Pierce, Laurence Thomas

2011-01-01

This thesis describes work carried out on the design of new routes to a range of bisindolylmaleimide and indolo[2,3-a]carbazole analogs, and investigation of their potential as successful anti-cancer agents. Following initial investigation of classical routes to indolo[2,3-a]pyrrolo[3,4-c]carbazole aglycons, a new strategy employing base-mediated condensation of thiourea and guanidine with a bisindolyl β-ketoester intermediate afforded novel 5,6-bisindolylpyrimidin-4(3H)-ones in moderat...

Research on neutron capture therapy in the USSR

International Nuclear Information System (INIS)

Ryabukhin, Y.

1988-01-01

Research on neutron capture therapy in the USSR began in 1964. Towards 1975 prime knowledge in physics, pharmacology and radiobiology had been accumulated. It was realized that inherent to NCT is a variety of modalities as to the type and location of the tumor, the energy and source of neutrons, the nature and transportation of the nuclide-carrying agent (NCA), etc. Thus, it became likely that some modalities would turn out to be clinically feasible. At the end of the 70s, studies of boron derivatives began at the All-Union Oncological Research Center, Moscow. These studies were stimulated by the clinical trials in Japan. Still, neutron capturing nuclides (NCN) other than 10 b are regarded as promising. Research was aimed at clinical trials that could ensure sufficient safety, convenience and conclusiveness. Hence, new requirements emerged, such as the pre-clinical modeling of NCT in big animals and the monitoring of tumor response to each fraction of NCT. Usual requirements are also to be met, that is: tailoring neutron beams with an adequate intensity and energy, choosing NCNs and finding suitable NCAs, physical and radiobiological planning including adoption of tentative RBEs and time-fractionation regimen, selecting tumors as candidates for NCT, and developing techniques for monitoring NCNs in vivo

Understanding the generative capacity of analogies as a tool for explanation

Science.gov (United States)

Wong, E. David

1993-12-01

Psychological studies have typically portrayed analogical reasoning as a process of schema transfer from a familiar domain of understanding to a problem situation. These studies have usually examined analogical reasoning in contexts where (a) individuals possess or have been provided with appropriate, problem-specific schema, (b) the nature of the problem and/or solution is fairly well defined, and (c) ideal analogies are provided or suggested by an outside source. This study examines analogical reasoning in contexts where understanding is generated from loosely organized, incomplete prior knowledge rather than transferred from a well-structured domain of understanding. In addition, participants were asked to create, apply, and modify their own analogies - as opposed to applying a given analogy - as a heuristic for constructing, evaluating, and modifying their explanations for a particular scientific phenomena. The results provide empirical support for the generative properties of analogies; that is, analogies can stimulate new inferences and insight. Furthermore, under specific conditions, individuals can productively harness the generative capacity of their own analogies to advance their conceptual understanding of scientific phenomena.

Interatomic Coulombic electron capture

International Nuclear Information System (INIS)

Gokhberg, K.; Cederbaum, L. S.

2010-01-01

In a previous publication [K. Gokhberg and L. S. Cederbaum, J. Phys. B 42, 231001 (2009)] we presented the interatomic Coulombic electron capture process--an efficient electron capture mechanism by atoms and ions in the presence of an environment. In the present work we derive and discuss the mechanism in detail. We demonstrate thereby that this mechanism belongs to a family of interatomic electron capture processes driven by electron correlation. In these processes the excess energy released in the capture event is transferred to the environment and used to ionize (or to excite) it. This family includes the processes where the capture is into the lowest or into an excited unoccupied orbital of an atom or ion and proceeds in step with the ionization (or excitation) of the environment, as well as the process where an intermediate autoionizing excited resonance state is formed in the capturing center which subsequently deexcites to a stable state transferring its excess energy to the environment. Detailed derivation of the asymptotic cross sections of these processes is presented. The derived expressions make clear that the environment assisted capture processes can be important for many systems. Illustrative examples are presented for a number of model systems for which the data needed to construct the various capture cross sections are available in the literature.

Transistor analogs of emergent iono-neuronal dynamics.

Science.gov (United States)

Rachmuth, Guy; Poon, Chi-Sang

2008-06-01

Neuromorphic analog metal-oxide-silicon (MOS) transistor circuits promise compact, low-power, and high-speed emulations of iono-neuronal dynamics orders-of-magnitude faster than digital simulation. However, their inherently limited input voltage dynamic range vs power consumption and silicon die area tradeoffs makes them highly sensitive to transistor mismatch due to fabrication inaccuracy, device noise, and other nonidealities. This limitation precludes robust analog very-large-scale-integration (aVLSI) circuits implementation of emergent iono-neuronal dynamics computations beyond simple spiking with limited ion channel dynamics. Here we present versatile neuromorphic analog building-block circuits that afford near-maximum voltage dynamic range operating within the low-power MOS transistor weak-inversion regime which is ideal for aVLSI implementation or implantable biomimetic device applications. The fabricated microchip allowed robust realization of dynamic iono-neuronal computations such as coincidence detection of presynaptic spikes or pre- and postsynaptic activities. As a critical performance benchmark, the high-speed and highly interactive iono-neuronal simulation capability on-chip enabled our prompt discovery of a minimal model of chaotic pacemaker bursting, an emergent iono-neuronal behavior of fundamental biological significance which has hitherto defied experimental testing or computational exploration via conventional digital or analog simulations. These compact and power-efficient transistor analogs of emergent iono-neuronal dynamics open new avenues for next-generation neuromorphic, neuroprosthetic, and brain-machine interface applications.

Emergent Explorations: Analog and Digital Scripting

OpenAIRE

Worden, Alexander

2011-01-01

This book documents an exploration of emergent and linear modes of defining space, form, and structure. The thesis highlights a dialog between analog and digital modeling techniques, in concept and project development. It identifies that analog modeling techniques, coupled with judgment, can be used to develop complex forms. The thesis project employs critical judgment and the textile techniques of crochet as a vehicle generate form. Crochet lends itself to this investigation because it ...

Enhanced Cell Capture on Functionalized Graphene Oxide Nanosheets through Oxygen Clustering.

Science.gov (United States)

Bardhan, Neelkanth M; Kumar, Priyank V; Li, Zeyang; Ploegh, Hidde L; Grossman, Jeffrey C; Belcher, Angela M; Chen, Guan-Yu

2017-02-28

With the global rise in incidence of cancer and infectious diseases, there is a need for the development of techniques to diagnose, treat, and monitor these conditions. The ability to efficiently capture and isolate cells and other biomolecules from peripheral whole blood for downstream analyses is a necessary requirement. Graphene oxide (GO) is an attractive template nanomaterial for such biosensing applications. Favorable properties include its two-dimensional architecture and wide range of functionalization chemistries, offering significant potential to tailor affinity toward aromatic functional groups expressed in biomolecules of interest. However, a limitation of current techniques is that as-synthesized GO nanosheets are used directly in sensing applications, and the benefits of their structural modification on the device performance have remained unexplored. Here, we report a microfluidic-free, sensitive, planar device on treated GO substrates to enable quick and efficient capture of Class-II MHC-positive cells from murine whole blood. We achieve this by using a mild thermal annealing treatment on the GO substrates, which drives a phase transformation through oxygen clustering. Using a combination of experimental observations and MD simulations, we demonstrate that this process leads to improved reactivity and density of functionalization of cell capture agents, resulting in an enhanced cell capture efficiency of 92 ± 7% at room temperature, almost double the efficiency afforded by devices made using as-synthesized GO (54 ± 3%). Our work highlights a scalable, cost-effective, general approach to improve the functionalization of GO, which creates diverse opportunities for various next-generation device applications.

Young Children's Analogical Reasoning in Science Domains

Science.gov (United States)

Haglund, Jesper; Jeppsson, Fredrik; Andersson, Johanna

2012-01-01

This exploratory study in a classroom setting investigates first graders' (age 7-8 years, N = 25) ability to perform analogical reasoning and create their own analogies for two irreversible natural phenomena: mixing and heat transfer. We found that the children who contributed actively to a full-class discussion were consistently successful at…

Children's Use of Analogy during Collaborative Reasoning

Science.gov (United States)

Lin, Tzu-Jung; Anderson, Richard C.; Hummel, John E.; Jadallah, May; Miller, Brian W.; Nguyen-Jahiel, Kim; Morris, Joshua A.; Kuo, Li-Jen; Kim, Il-Hee; Wu, Xiaoying; Dong, Ting

2012-01-01

This microgenetic study examined social influences on children's development of analogical reasoning during peer-led small-group discussions of stories about controversial issues. A total of 277 analogies were identified among 7,215 child turns for speaking during 54 discussions from 18 discussion groups in 6 fourth-grade classrooms (N = 120; age…

A physical data model for fields and agents

Science.gov (United States)

de Jong, Kor; de Bakker, Merijn; Karssenberg, Derek

2016-04-01

Two approaches exist in simulation modeling: agent-based and field-based modeling. In agent-based (or individual-based) simulation modeling, the entities representing the system's state are represented by objects, which are bounded in space and time. Individual objects, like an animal, a house, or a more abstract entity like a country's economy, have properties representing their state. In an agent-based model this state is manipulated. In field-based modeling, the entities representing the system's state are represented by fields. Fields capture the state of a continuous property within a spatial extent, examples of which are elevation, atmospheric pressure, and water flow velocity. With respect to the technology used to create these models, the domains of agent-based and field-based modeling have often been separate worlds. In environmental modeling, widely used logical data models include feature data models for point, line and polygon objects, and the raster data model for fields. Simulation models are often either agent-based or field-based, even though the modeled system might contain both entities that are better represented by individuals and entities that are better represented by fields. We think that the reason for this dichotomy in kinds of models might be that the traditional object and field data models underlying those models are relatively low level. We have developed a higher level conceptual data model for representing both non-spatial and spatial objects, and spatial fields (De Bakker et al. 2016). Based on this conceptual data model we designed a logical and physical data model for representing many kinds of data, including the kinds used in earth system modeling (e.g. hydrological and ecological models). The goal of this work is to be able to create high level code and tools for the creation of models in which entities are representable by both objects and fields. Our conceptual data model is capable of representing the traditional feature data

Carbon captured from the air

Energy Technology Data Exchange (ETDEWEB)

Keith, D. [Calgary Univ., AB (Canada)

2008-10-15

This article presented an innovative way to achieve the efficient capture of atmospheric carbon. A team of scientists from the University of Calgary's Institute for Sustainable Energy, Environment and Economy have shown that it is possible to reduce carbon dioxide (CO{sub 2}) using a simple machine that can capture the trace amount of CO{sub 2} present in ambient air at any place on the planet. The thermodynamics of capturing the small concentrations of CO{sub 2} from the air is only slightly more difficult than capturing much larger concentrations of CO{sub 2} from power plants. The research is significant because it offers a way to capture CO{sub 2} emissions from transportation sources such as vehicles and airplanes, which represent more than half of the greenhouse gases emitted on Earth. The energy efficient and cost effective air capture technology could complement other approaches for reducing emissions from the transportation sector, such as biofuels and electric vehicles. Air capture differs from carbon capture and storage (CCS) technology used at coal-fired power plants where CO{sub 2} is captured and pipelined for permanent storage underground. Air capture can capture the CO{sub 2} that is present in ambient air and store it wherever it is cheapest. The team at the University of Calgary showed that CO{sub 2} could be captured directly from the air with less than 100 kWhrs of electricity per tonne of CO{sub 2}. A custom-built tower was able to capture the equivalent of 20 tonnes per year of CO{sub 2} on a single square meter of scrubbing material. The team devised a way to use a chemical process from the pulp and paper industry to cut the energy cost of air capture in half. Although the technology is only in its early stage, it appears that CO{sub 2} could be captured from the air with an energy demand comparable to that needed for CO{sub 2} capture from conventional power plants, but costs will be higher. The simple, reliable and scalable technology

A protein chip membrane-capture assay for botulinum neurotoxin activity

International Nuclear Information System (INIS)

Marconi, Severine; Ferracci, Geraldine; Berthomieu, Maelys; Kozaki, Shunji; Miquelis, Raymond; Boucraut, Jose; Seagar, Michael

2008-01-01

Botulinum neurotoxins A and B (BoNT/A and B) are neuromuscular blocking agents which inhibit neurotransmission by cleaving the intra-cellular presynaptic SNARE proteins SNAP-25 and VAMP2, localized respectively in plasma membrane and synaptic vesicles. These neurotoxins are both dangerous pathogens and powerful therapeutic agents with numerous clinical and cosmetic applications. Consequently there is a need for in vitro assays of their biological activity to screen for potential inhibitors and to replace the widely used in vivo mouse assay. Surface plasmon resonance (SPR) was used to measure membrane vesicle capture by antibodies against SNAP-25 and VAMP2. Substrate cleavage by BoNTs modified capture providing a method to assay toxin activity. Firstly using synaptic vesicles as a substrate, a comparison of the EC 50 s for BoNT/B obtained by SPR, ELISA or flow cytometry indicated similar sensitivity although SPR assays were more rapid. Sonication of brain or neuronal cultures generated plasma membrane fragments with accessible intra-cellular epitopes adapted to measurement of BoNT/A activity. SPR responses were proportional to antigen concentration permitting detection of as little as 4 pM SNAP-25 in crude lysates. BoNT/A activity was assayed using monoclonal antibodies that specifically recognize a SNAP-25 epitope generated by the proteolytic action of the toxin. Incubation of intact primary cultured neurons with BoNT/A yielded an EC 50 of 0.5 pM. The SPR biosensor method was sensitive enough to monitor BoNT/A and B activity in cells cultured in a 96-well format providing an alternative to experimental animals for toxicological assays

Analogical Reasoning in the Engineering Design Process and Technology Education Applications

Science.gov (United States)

Daugherty, Jenny; Mentzer, Nathan

2008-01-01

This synthesis paper discusses the research exploring analogical reasoning, the role of analogies in the engineering design process, and educational applications for analogical reasoning. Researchers have discovered that analogical reasoning is often a fundamental cognitive tool in design problem solving. Regarding the possible role of analogical…

Design and evaluation of novel interferon lambda analogs with enhanced antiviral activity and improved drug attributes

Directory of Open Access Journals (Sweden)

Yu D

2016-01-01

Full Text Available Debin Yu,1 Mingzhi Zhao,2 Liwei Dong,1 Lu Zhao,1 Mingwei Zou,3 Hetong Sun,4 Mengying Zhang,4 Hongyu Liu,4 Zhihua Zou1 1National Engineering Laboratory for AIDS Vaccine, Key Laboratory for Molecular Enzymology and Engineering of the Ministry of Education, School of Life Sciences, Jilin University, Changchun, 2State Key Laboratory of Proteomics, National Engineering Research Center for Protein Drugs, Beijing Proteome Research Center, Beijing Institute of Radiation Medicine, Beijing, People’s Republic of China; 3Department of Psychology, College of Liberal Arts and Social Sciences, University of Houston, Houston, TX, USA; 4Prosit Sole Biotechnology, Co., Ltd., Beijing, People’s Republic of China Abstract: Type III interferons (IFNs (also called IFN-λ: IFN-λ1, IFN-λ2, IFN-λ3, and IFN-λ4 are critical players in the defense against viral infection of mucosal epithelial cells, where the activity of type I IFNs is weak, and unlike type I IFNs that are associated with severe and diverse side effects, type III IFNs cause minimal side effects due to the highly restricted expression of their receptors, and thus appear to be promising agents for the treatment and prevention of respiratory and gastrointestinal viral infection. However, the antiviral potency of natural type III IFNs is weak compared to type I and, although IFN-λ3 possesses the highest bioactivity among the type III IFNs, IFN-λ1, instead of IFN-λ3, is being developed as a therapeutic drug due to the difficulty to express IFN-λ3 in the prokaryotic expression system. Here, to develop optimal IFN-λ molecules with improved drug attributes, we designed a series of IFN-λ analogs by replacing critical amino acids of IFN-λ1 with the IFN-λ3 counterparts, and vice versa. Four of the designed analogs were successfully expressed in Escherichia coli with high yield and were easily purified from inclusion bodies. Interestingly, all four analogs showed potent activity in inducing the

Global orbit feedback utilizing analog and digital technologies

International Nuclear Information System (INIS)

Singh, O.; Tang, Y.; Ramamoorthy, S.; Krinsky, S.; Yu, L.H.

1997-01-01

At the NSLS, an analog global orbit feedback system is used in regular operations, and a digital global orbit feedback system is available in machine physics studies on the X-Ray Ring. Here, the authors discuss the relative merits of utilizing analog and digital technology in orbit feedback. Results of experiments are reported characterizing the performance of the analog and digital systems when operated individually or together. They give their thoughts on plans for future development of the orbit feedback systems at the NSLS

Effects of Multimedia and Schema Induced Analogical Reasoning on Science Learning

Science.gov (United States)

Zheng, R. Z.; Yang, W.; Garcia, D.; McCadden, E. P.

2008-01-01

The present study investigates the effects of multimedia and schema induced analogical reasoning on science learning. It involves 89 fourth grade elementary students in the north-east of the United States. Participants are randomly assigned into four conditions: (a) multimedia with analogy; (b) multimedia without analogy; (c) analogy without…

An analog integrated circuit design laboratory

OpenAIRE

Mondragon-Torres, A.F.; Mayhugh, Jr.; Pineda de Gyvez, J.; Silva-Martinez, J.; Sanchez-Sinencio, E.

2003-01-01

We present the structure of an analog integrated circuit design laboratory to instruct at both, senior undergraduate and entry graduate levels. The teaching material includes: a laboratory manual with analog circuit design theory, pre-laboratory exercises and circuit design specifications; a reference web page with step by step instructions and examples; the use of mathematical tools for automation and analysis; and state of the art CAD design tools in use by industry. Upon completion of the ...

On Lovelock analogs of the Riemann tensor

Science.gov (United States)

Camanho, Xián O.; Dadhich, Naresh

2016-03-01

It is possible to define an analog of the Riemann tensor for Nth order Lovelock gravity, its characterizing property being that the trace of its Bianchi derivative yields the corresponding analog of the Einstein tensor. Interestingly there exist two parallel but distinct such analogs and the main purpose of this note is to reconcile both formulations. In addition we will introduce a simple tensor identity and use it to show that any pure Lovelock vacuum in odd d=2N+1 dimensions is Lovelock flat, i.e. any vacuum solution of the theory has vanishing Lovelock-Riemann tensor. Further, in the presence of cosmological constant it is the Lovelock-Weyl tensor that vanishes.

Psychometric evaluation of a visual analog scale for the assessment of anxiety

Directory of Open Access Journals (Sweden)

Morlock Robert J

2010-06-01

Full Text Available Abstract Background Fast-acting medications for the management of anxiety are important to patients and society. Measuring early onset, however, requires a sensitive and clinically responsive tool. This study evaluates the psychometric properties of a patient-reported Global Anxiety - Visual Analog Scale (GA-VAS. Methods Data from a double-blind, randomized, placebo-controlled study of lorazepam and paroxetine in patients with Generalized Anxiety Disorder were analyzed to assess the reliability, validity, responsiveness, and utility of the GA-VAS. The GA-VAS was completed at clinic visits and at home during the first week of treatment. Targeted psychometric analyses—test-retest reliabilities, validity correlations, responsiveness statistics, and minimum important differences—were conducted. Results The GA-VAS correlates well with other anxiety measures, at Week 4, r = 0.60 (p r = 0.74 (p p p p Conclusions The GA-VAS is capable of validly and effectively capturing a reduction in anxiety as quickly as 24 hours post-dose.

Development and operation of a 6LiF:ZnS(Ag)-scintillating plastic capture-gated detector

Science.gov (United States)

Wilhelm, K.; Nattress, J.; Jovanovic, I.

2017-01-01

We report on the design, construction, and operation of a capture-gated neutron detector based on a heterogeneous scintillating structure comprising two scintillator types. A flat, 500 μm thick sheet composed of a mixture of lithium-6-fluoride capture agent, 6LiF, and zinc sulfide phosphor, ZnS(Ag), is wrapped around scintillating polyvinyl toluene (PVT) in a form of cylinder. The 6LiF: ZnS(Ag) sheet uses an aluminum foil backing as a support for the scintillating material and as an optical reflector, and its optical properties have been characterized independently. The composite scintillator was tested using 252Cf, DD fusion, 137Cs, and 60Co sources. The intrinsic detection efficiency for neutrons from an unmoderated 252Cf source and rejection of gammas from 137Cs were measured to be 3.6 % and 10-6, respectively. A figure of merit for pulse shape discrimination of 4.6 was achieved, and capture-gated spectroscopic analysis is demonstrated.

Analogies in high school Brazilian chemistry textbooks

Directory of Open Access Journals (Sweden)

Rosária Justi

2000-05-01

Full Text Available This paper presents and discusses an analysis of the analogies presented by Brazilian chemistry textbooks for the medium level. The main aim of the analysis is to discuss whether such analogies can be said good teaching models. From the results, some aspects concerning with teachers' role are discussed. Finally, some new research questions are emphasised.

Capture programs, analysis, data graphication for the study of the thermometry of the TRIGA Mark III reactor core

International Nuclear Information System (INIS)

Paredes G, L.C.

1991-05-01

This document covers the explanation of the capture programs, analysis and graphs of the data obtained during the measurement of the temperatures of the instrumented fuel element of the TRIGA Mark III reactor and of the coolant one near to this fuel, using the conversion card from Analogic to Digital of 'Data Translation', and using a signal conditioner for five temperature measurers with the help of thermo par type K, developed by the Simulation and Control of the nuclear systems management department, which gives a signal from 0 to 10 Vcd for an interval of temperature of 0 to 1000 C. (Author)

Analogy, an Alternative Model.
 Critics to the standard model of analogical problems solving and proposals for an alternative one

Directory of Open Access Journals (Sweden)

Ricardo A. Minervino

2016-02-01

Full Text Available The authors made an extension of Hofstadter‘s criticisms against the standard approach in analogical thinking represented by the structure-mapping theory of Gentner and the multiconstraint theory of Holyoak and Thagard. Based on this extension, they proposed a non-serial model of analogical problem solving. Against the standard approach, the model postulates that: (a people detect and evaluate differences between mapped elements before the subprocess of inference generation and consider them in order to control it, and (b properties of an element that explain why the element could fill a certain role in the base problem resolution (PERs play a crucial role in these detection and evaluation operations, and also in post-inferences subprocesses. An experiment showed that: (a people detect and evaluate the relevance of differences between mapped elements before inference generation, (b that they inhibit the generation of literal inferences when they face relevant differences, and (c that they stop the subprocess when they recognize insuperable ones. The results also showed that base PERs are reactivated at different moments of analogical transfer. The data obtained are incompatible with the standard theories of analogical thinking, which treat inference generation as a syntactic mechanism and exclude contextual semantic analysis from the study of analogy. 

The making of analog module for gamma camera interface

International Nuclear Information System (INIS)

Yulinarsari, Leli; Rl, Tjutju; Susila, Atang; Sukandar

2003-01-01

The making of an analog module for gamma camera has been conducted. For computerization of planar gamma camera 37 PMT it has been developed interface hardware technology and software between the planar gamma camera with PC. With this interface gamma camera image information (Originally analog signal) was changed to digital single, therefore processes of data acquisition, image quality increase and data analysis as well as data base processing can be conducted with the help of computers, there are three gamma camera main signals, i.e. X, Y and Z . This analog module makes digitation of analog signal X and Y from the gamma camera that conveys position information coming from the gamma camera crystal. Analog conversion to digital was conducted by 2 converters ADC 12 bit with conversion time 800 ns each, conversion procedure for each coordinate X and Y was synchronized using suitable strobe signal Z for information acceptance

Final Report: 8th International Symposium on Neutron Capture Therapy (NCT) for Cancer, May 15, 1998 - May 15, 1999

International Nuclear Information System (INIS)

Hawthorne, M.F.

1999-01-01

The 8th International Symposium on Neutron Capture Therapy for Cancer (8th ISNCTC) was held in La Jolla, CA on Sept. 13-18, 1998. This biennial meeting of the International Society for Neutron Capture Therapy (ISNCT) was hosted by Society President M.F. Hawthorne (UCLA Dept. of Chemistry and Biochemistry). The Symposium brought together scientists (300 registrants from 21 countries) from diverse fields to report the latest developments in NCT. Topics of the 275 papers presented (30 plenary lectures, 81 oral presentations, and 164 posters) included the physics of neutron sources, chemistry of tumor-targeting agents, dosimetry, radiobiological studies, and clinical applications

Children's analogical reasoning in a third-grade science discussion

Science.gov (United States)

May, David B.; Hammer, David; Roy, Patricia

2006-03-01

Expert scientific inquiry involves the generation and use of analogies. How and when students might develop this aspect of expertise has implications for understanding how and when instruction might facilitate that development. In a study of K-8 student inquiry in physical science, we are examining cases of spontaneous analogy generation. In the case we present here, a third-grader generates an analogy and modifies it to reconcile his classmates' counterarguments, allowing us to identify in these third-graders specific aspects of nascent expertise in analogy use. Promoting abilities and inclinations such as these children display requires that educators recognize and respond to them.

Leibniz y el concepto de analogía

Directory of Open Access Journals (Sweden)

Oscar Miguel Esquisabel

2008-11-01

Full Text Available In this paper an analysis of the leibnizian applications of conceptof analogy as well as the analogical reasoning is approached. Thus, the analysis tries to show that the leibnizian concept of analogy is based on the idea of structural similarity. As a consequence of such consideration,two basic ways in which Leibniz applies analogical reasoning are examined. The first way has a conjectural character and is rather heuristic, whereas the second constitutes, at least in intention, a kind of demonstrative analogicalreasoning, since it tries to prove its conclusions for a determined theoreticaldomain by applying a transfer principle, which is itself founded on the identity of structural properties.This procedure is exemplified by outlining the leibnizian view on contingent truths. In this way, the paper concludesby pointing out the theoretical relevance of the concept of similarity in theleibnizian thought.

Low concentration CO2 capture using physical adsorbents: Are Metal-Organic Frameworks becoming the new benchmark materials?

KAUST Repository

Belmabkhout, Youssef; Guillerm, Vincent; Eddaoudi, Mohamed

2016-01-01

The capture and separation of traces and concentrated CO2 from important commodities such as CH4, H2, O2 and N2, is becoming important in many areas related to energy security and environmental sustainability. While trace CO2 concentration removal applications have been modestly studied for decades, the spike in interest in the capture of concentrated CO2 was motivated by the need for new energy vectors to replace highly concentrated carbon fuels and the necessity to reduce emissions from fossil fuel-fired power plants. CO2 capture from various gas streams, at different concentrations, using physical adsorbents, such as activated carbon, zeolites, and metal-organic frameworks (MOFs), is attractive. However, the adsorbents must be designed with consideration of many parameters including CO2 affinity, kinetics, energetics, stability, capture mechanism, in addition to cost. Here, we perform a systematic analysis regarding the key technical parameters that are required for the best CO2 capture performance using physical adsorbents. We also experimentally demonstrate a suitable material model of Metal Organic Framework as advanced adsorbents with unprecedented properties for CO2 capture in a wide range of CO2 concentration. These recently developed class of MOF adsorbents represent a breakthrough finding in the removal of traces CO2 using physical adsorption. This platform shows colossal tuning potential for more efficient separation agents.

Low concentration CO2 capture using physical adsorbents: Are Metal-Organic Frameworks becoming the new benchmark materials?

KAUST Repository

Belmabkhout, Youssef

2016-03-30

The capture and separation of traces and concentrated CO2 from important commodities such as CH4, H2, O2 and N2, is becoming important in many areas related to energy security and environmental sustainability. While trace CO2 concentration removal applications have been modestly studied for decades, the spike in interest in the capture of concentrated CO2 was motivated by the need for new energy vectors to replace highly concentrated carbon fuels and the necessity to reduce emissions from fossil fuel-fired power plants. CO2 capture from various gas streams, at different concentrations, using physical adsorbents, such as activated carbon, zeolites, and metal-organic frameworks (MOFs), is attractive. However, the adsorbents must be designed with consideration of many parameters including CO2 affinity, kinetics, energetics, stability, capture mechanism, in addition to cost. Here, we perform a systematic analysis regarding the key technical parameters that are required for the best CO2 capture performance using physical adsorbents. We also experimentally demonstrate a suitable material model of Metal Organic Framework as advanced adsorbents with unprecedented properties for CO2 capture in a wide range of CO2 concentration. These recently developed class of MOF adsorbents represent a breakthrough finding in the removal of traces CO2 using physical adsorption. This platform shows colossal tuning potential for more efficient separation agents.

The Discourse on Printed and Electronic Books: Analogies, Oppositions, and Perspectives

Science.gov (United States)

Velagic, Zoran

2014-01-01

Introduction: The point of departure for this paper is the twofold analogy (analogy of content, analogy of medium) between printed and electronic books, the aim being to draw attention to the usual perception of their capacities and relationships, to provide a rather detailed analysis of the outcome and sustainability of such analogies and…

Source selection for analogical reasoning an empirical approach

Energy Technology Data Exchange (ETDEWEB)

Stubblefield, W.A. [Sandia National Labs., Albuquerque, NM (United States); Luger, G.F. [Univ. of New Mexico, Albuquerque, NM (United States)

1996-12-31

The effectiveness of an analogical reasoner depends upon its ability to select a relevant analogical source. In many problem domains, however, too little is known about target problems to support effective source selection. This paper describes the design and evaluation of SCAVENGER, an analogical reasoner that applies two techniques to this problem: (1) An assumption-based approach to matching that allows properties of candidate sources to match unknown target properties in the absence of evidence to the contrary. (2) The use of empirical learning to improve memory organization based on problem solving experience.

Creative Analogy Use in a Heterogeneous Design Team

DEFF Research Database (Denmark)

Christensen, Bo; Ball, Linden J.

2016-01-01

the design dialogue derived from team members with highly disparate educational backgrounds. Our analyses revealed that analogies that matched (versus mismatched) educational backgrounds were generated and revisited more frequently, presumably because they were more accessible. Matching analogies were also...

Detection of Pseudogymnoascus destructans on Free-flying Male Bats Captured During Summer in the Southeastern USA.

Science.gov (United States)

Carpenter, Grace M; Willcox, Emma V; Bernard, Riley F; H Stiver, William

2016-10-01

Pseudogymnoascus destructans, the causal agent of white-nose syndrome (WNS), is commonly found on bats captured both inside and outside caves during hibernation, a time when bats are most vulnerable to infection. It has not been documented in the southeast US on bats captured outside caves or on the landscape in summer. We collected 136 skin swabs from 10 species of bats captured at 20 sites on the Tennessee side of Great Smoky Mountains National Park, 12 May-16 August 2015. Three swabs were found positive for P. destructans, one from a male tricolored bat ( Perimyotis subflavus ) and two from male big brown bats ( Eptesicus fuscus ). This detection of P. destructans on free-flying male bats in the southeast US during summer has potential repercussions for the spread of the fungus to novel bat species and environments. Our finding emphasizes the need to maintain rigorous year-round decontamination of field clothing and equipment until more is understood about the viability of P. destructans found on bats captured outside hibernacula during summer, about the potential for males to act as reservoirs of the fungus, and the risk of fungal transmission and spread.

Electronic devices for analog signal processing

CERN Document Server

Rybin, Yu K

2012-01-01

Electronic Devices for Analog Signal Processing is intended for engineers and post graduates and considers electronic devices applied to process analog signals in instrument making, automation, measurements, and other branches of technology. They perform various transformations of electrical signals: scaling, integration, logarithming, etc. The need in their deeper study is caused, on the one hand, by the extension of the forms of the input signal and increasing accuracy and performance of such devices, and on the other hand, new devices constantly emerge and are already widely used in practice, but no information about them are written in books on electronics. The basic approach of presenting the material in Electronic Devices for Analog Signal Processing can be formulated as follows: the study with help from self-education. While divided into seven chapters, each chapter contains theoretical material, examples of practical problems, questions and tests. The most difficult questions are marked by a diamon...

Synthesis and anti-inflammatory activity of phenylbutenoid dimer analogs

International Nuclear Information System (INIS)

Kim, Sung Soo; Fang, Yuan Ying; Park, Hae Eil

2015-01-01

Several phenylbutenoid dimer (PBD) analogs were synthesized and evaluated for their inhibitory activities against nitric oxide (NO) production and TNF-α release. The PBD analogs were synthesized via Diels–Alder and subsequent Schlosser reactions as key steps. Among the tested compounds, two analogs (8c, 8f) exhibited much stronger inhibitory activity against LPS-stimulated NO production and TNF-α release in RAW 264.7 cells than that of wogonin

BERAS ANALOG SEBAGAI PANGAN FUNGSIONAL DENGAN INDEKS GLIKEMIK RENDAH

Directory of Open Access Journals (Sweden)

Santi Noviasari

2016-04-01

Full Text Available ABSTRACTThe objective of this research was to produce rice analogue as functional food with low glycemic index. The rice was made from white corn and sorghum with additional soybean flour. The physicochemical properties of rice analogue being analysed were resistant starch content, total phenolic content, dietary fiber, color (L*, +a, +b values and whiteness (oHue. Rice analogue was potentially used as functional food indicated by high level of resistant starch 2.59%-3.31%, total phenolic content 0.18-0.25 mg GAE/g sample and dietary fiber 5.35%-6.14%. Rice analogue from white corn with and without soybean flour was further tested for glycemic index. Rice analogue from white corn has 69 GI value, while rice analogue from white corn with 10% soybean flour addition has 50 GI value.Keywords: functional food, glycemic index, rice analogueABSTRAKTujuan penelitian ini adalah untuk mendapatkan beras analog yang berpotensi sebagai pangan fungsional dan bernilai indeks glikemik rendah. Beras analog dibuat dari bahan baku jagung putih dan sorgum dengan penambahan tepung kedelai. Sifat fisiko kimia beras analog yang dianalisis adalah pati resisten, total fenol, serat pangan, warna (nilai L*, +a, +b dan derajat putih (oHue. Beras analog berpotensi sebagai pangan fungsional, yang ditunjukkan dengan tingginya kadar pati resisten yaitu sebanyak 2,59%-3,31%, total fenol sekitar 0,18-0,25 mg GAE/g sampel dan serat pangan antara 5,35%-6,14%. Beras analog berbahan baku jagung putih dengan dan tanpa penambahan kedelai dipilih untuk uji indeks glikemik. Beras analog dari jagung putih memiliki nilai IG 69 sedangkan beras analog dari jagung putih dengan penambahan tepung kedelai 10% memiliki nilai IG 50.Kata kunci: beras analog, indeks glikemik, pangan fungsional

Nitrate analogs as attractants for soybean cyst nematode.

Science.gov (United States)

Hosoi, Akito; Katsuyama, Tsutomu; Sasaki, Yasuyuki; Kondo, Tatsuhiko; Yajima, Shunsuke; Ito, Shinsaku

2017-08-01

Soybean cyst nematode (SCN) Heterodera glycines Ichinohe, a plant parasite, is one of the most serious pests of soybean. In this paper, we report that SCN is attracted to nitrate and its analogs. We performed attraction assays to screen for novel attractants for SCN and found that nitrates were attractants for SCN and SCN recognized nitrate gradients. However, attraction of SCN to nitrates was not observed on agar containing nitrate. To further elucidate the attraction mechanism in SCN, we performed attraction assays using nitrate analogs ([Formula: see text], [Formula: see text], [Formula: see text]). SCN was attracted to all nitrate analogs; however, attraction of SCN to nitrate analogs was not observed on agar containing nitrate. In contrast, SCN was attracted to azuki root, irrespective of presence or absence of nitrate in agar media. Our results suggest that the attraction mechanisms differ between plant-derived attractant and nitrate.

Reference-Free CMOS Pipeline Analog-to-Digital Converters

CERN Document Server

Figueiredo, Michael; Evans, Guiomar

2013-01-01

This book shows that digitally assisted analog-to-digital converters are not the only way to cope with poor analog performance caused by technology scaling. It describes various analog design techniques that enhance the area and power efficiency without employing any type of digital calibration circuitry. These techniques consist of self-biasing for PVT enhancement, inverter-based design for improved speed/power ratio, gain-of-two obtained by voltage sum instead of charge redistribution, and current-mode reference shifting instead of voltage reference shifting. Together, these techniques allow enhancing the area and power efficiency of the main building blocks of a multiplying digital-to-analog converter (MDAC) based stage, namely, the flash quantizer, the amplifier, and the switched capacitor network of the MDAC. Complementing the theoretical analyses of the various techniques, a power efficient operational transconductance amplifier is implemented and experimentally characterized. Furthermore, a medium-low ...

Sequestering agents for the removal of actinides from waste streams

Energy Technology Data Exchange (ETDEWEB)

Raymond, K.N.; White, D.J.; Xu, Jide; Mohs, T.R. [Univ. of California, Berkeley, CA (United States)

1997-10-01

The goal of this project is to take a biomimetic approach toward developing new separation technologies for the removal of radioactive elements from contaminated DOE sites. To achieve this objective, the authors are investigating the fundamental chemistry of naturally occurring, highly specific metal ion sequestering agents and developing them into liquid/liquid and solid supported actinide extraction agents. Nature produces sideophores (e.g., Enterobactin and Desferrioxamine B) to selectivity sequester Lewis acidic metal ions, in particular Fe(III), from its surroundings. These chelating agents typically use multiple catechols or hydroxamic acids to form polydentate ligands that chelate the metal ion forming very stable complexes. The authors are investigating and developing analogous molecules into selective chelators targeting actinide(IV) ions, which display similar properties to Fe(III). By taking advantage of differences in charge, preferred coordination number, and pH stability range, the transition from nature to actinide sequestering agents has been applied to the development of new and highly selective actinide extraction technologies. Additionally, the authors have shown that these chelating ligands are versatile ligands for chelating U(VI). In particular, they have been studying their coordination chemistry and fundamental interactions with the uranyl ion [UO{sub 2}]{sup 2+}, the dominant form of uranium found in aqueous media. With an understanding of this chemistry, and results obtained from in vivo uranium sequestration studies, it should be possible to apply these actinide(IV) extraction technologies to the development of new extraction agents for the removal of uranium from waste streams.

When Reasoning Modifies Memory: Schematic Assimilation Triggered by Analogical Mapping

Science.gov (United States)

Vendetti, Michael S.; Wu, Aaron; Rowshanshad, Ebi; Knowlton, Barbara J.; Holyoak, Keith J.

2014-01-01

Analogical mapping highlights shared relations that link 2 situations, potentially at the expense of information that does not fit the dominant pattern of correspondences. To investigate whether analogical mapping can alter subsequent recognition memory for features of a source analog, we performed 2 experiments with 4-term proportional analogies…

Between Complexity and Parsimony: Can Agent-Based Modelling Resolve the Trade-off

DEFF Research Database (Denmark)

Nielsen, Helle Ørsted; Malawska, Anna Katarzyna

2013-01-01

to BR- based policy studies would be to couple research on bounded ra-tionality with agent-based modeling. Agent-based models (ABMs) are computational models for simulating the behavior and interactions of any number of decision makers in a dynamic system. Agent-based models are better suited than...... are general equilibrium models for capturing behavior patterns of complex systems. ABMs may have the potential to represent complex systems without oversimplifying them. At the same time, research in bounded rationality and behavioral economics has already yielded many insights that could inform the modeling......While Herbert Simon espoused development of general models of behavior, he also strongly advo-cated that these models be based on realistic assumptions about humans and therefore reflect the complexity of human cognition and social systems (Simon 1997). Hence, the model of bounded rationality...

A heat exchanger analogy of automotive paint ovens

International Nuclear Information System (INIS)

Rao, Preetham P.

2013-01-01

Computational prediction of vehicle temperatures in an automotive paint oven is essential to predict paint quality and manufacturability. The complex geometry of vehicles, varying scales in the flow, transient nature of the process, and the tightly coupled conjugate heat transfer render the numerical models computationally very expensive. Here, a novel, simplified model of the oven is developed using an analogy to a three-stream cross flow heat exchanger that transfers heat from air to a series of moving bodies and supporting carriers. The analogous heat exchanger equations are developed and solved numerically. Steady state Computational Fluid Dynamics (CFD) simulations are carried out to model the flow field and to extract the heat transfer coefficients around the body and carriers. The air temperature distribution from the CFD models is used as a boundary condition in the analogous model. Correction coefficients are used in the analogy to take care of various assumptions. These are determined from existing test data. The same corrections are used to predict air temperatures for a modified configuration of the oven and a different vehicle. The method can be used to conduct control volume analysis of ovens to determine energy efficiency, and to study new vehicle or oven designs. -- Highlights: • Analogy of an automotive paint oven as a three stream cross flow heat exchanger. • The three streams are vehicle bodies, carriers and hot air. • Convection coefficients and inlet air stream temperatures from steady CFD simulations. • Analogy useful for overall energy efficiency analysis of conveyor ovens in general

Analogical Reasoning in Children with Specific Language Impairment

Science.gov (United States)

Leroy, Sandrine; Parisse, Christophe; Maillart, Christelle

2012-01-01

Usage-based theory considers analogical reasoning as a cognitive process required in language development. We hypothesized that difficulties with analogical reasoning could hinder the abstraction of construction schemas, thus slowing down morphosyntactic development for children with specific language impairment (SLI). We also hypothesized, in…

Analogies in Medicine: Valuable for Learning, Reasoning, Remembering and Naming

Science.gov (United States)

Pena, Gil Patrus; Andrade-Filho, Jose de Souza

2010-01-01

Analogies are important tools in human reasoning and learning, for resolving problems and providing arguments, and are extensively used in medicine. Analogy and similarity involve a structural alignment or mapping between domains. This cognitive mechanism can be used to make inferences and learn new abstractions. Through analogies, we try to…

Spanish Velar-Insertion and Analogy: A Usage-Based Diachronic Analysis

Science.gov (United States)

Fondow, Steven Richard

2010-01-01

The theory of Analogical and Exemplar Modeling (AEM) suggests renewed discussion of the formalization of analogy and its possible incorporation in linguistic theory. AEM is a usage-based model founded upon Exemplar Modeling (Bybee 2007, Pierrehumbert 2001) that utilizes several principles of the Analogical Modeling of Language (Skousen 1992, 1995,…

Multilateral Research Opportunities in Ground Analogs

Science.gov (United States)

Corbin, Barbara J.

2015-01-01

The global economy forces many nations to consider their national investments and make difficult decisions regarding their investment in future exploration. International collaboration provides an opportunity to leverage other nations' investments to meet common goals. The Humans In Space Community shares a common goal to enable safe, reliable, and productive human space exploration within and beyond Low Earth Orbit. Meeting this goal requires efficient use of limited resources and International capabilities. The International Space Station (ISS) is our primary platform to conduct microgravity research targeted at reducing human health and performance risks for exploration missions. Access to ISS resources, however, is becoming more and more constrained and will only be available through 2020 or 2024. NASA's Human Research Program (HRP) is actively pursuing methods to effectively utilize the ISS and appropriate ground analogs to understand and mitigate human health and performance risks prior to embarking on human exploration of deep space destinations. HRP developed a plan to use ground analogs of increasing fidelity to address questions related to exploration missions and is inviting International participation in these planned campaigns. Using established working groups and multilateral panels, the HRP is working with multiple Space Agencies to invite International participation in a series of 30- day missions that HRP will conduct in the US owned and operated Human Exploration Research Analog (HERA) during 2016. In addition, the HRP is negotiating access to Antarctic stations (both US and non-US), the German :envihab and Russian NEK facilities. These facilities provide unique capabilities to address critical research questions requiring longer duration simulation or isolation. We are negotiating release of international research opportunities to ensure a multilateral approach to future analog research campaigns, hoping to begin multilateral campaigns in the

SSERVI Analog Regolith Simulant Testbed Facility

Science.gov (United States)

Minafra, J.; Schmidt, G. K.

2016-12-01

SSERVI's goals include supporting planetary researchers within NASA, other government agencies; private sector and hardware developers; competitors in focused prize design competitions; and academic sector researchers. The SSERVI Analog Regolith Simulant Testbed provides opportunities for research scientists and engineers to study the effects of regolith analog testbed research in the planetary exploration field. This capability is essential to help to understand the basic effects of continued long-term exposure to a simulated analog test environment. The current facility houses approximately eight tons of JSC-1A lunar regolith simulant in a test bin consisting of a 4 meter by 4 meter area. SSERVI provides a bridge between several groups, joining together researchers from: 1) scientific and exploration communities, 2) multiple disciplines across a wide range of planetary sciences, and 3) domestic and international communities and partnerships. This testbed provides a means of consolidating the tasks of acquisition, storage and safety mitigation in handling large quantities of regolith simulant Facility hardware and environment testing scenarios include, but are not limited to the following; Lunar surface mobility, Dust exposure and mitigation, Regolith handling and excavation, Solar-like illumination, Lunar surface compaction profile, Lofted dust, Mechanical properties of lunar regolith, and Surface features (i.e. grades and rocks) Numerous benefits vary from easy access to a controlled analog regolith simulant testbed, and planetary exploration activities at NASA Research Park, to academia and expanded commercial opportunities in California's Silicon Valley, as well as public outreach and education opportunities.

Neuroscientific Insights into the Development of Analogical Reasoning

Science.gov (United States)

Whitaker, Kirstie J.; Vendetti, Michael S.; Wendelken, Carter; Bunge, Silvia A.

2018-01-01

Analogical reasoning, or the ability to find correspondences between entities based on shared relationships, supports knowledge acquisition. As such, the development of this ability during childhood is thought to promote learning. Here, we sought to better understand the mechanisms by which analogical reasoning about semantic relations improves…

Cross-Domain Analogies as Relating Derived Relations among Two Separate Relational Networks

Science.gov (United States)

Ruiz, Francisco J; Luciano, Carmen

2011-01-01

Contemporary behavior analytic research is making headway in analyzing analogy as the establishment of a relation of coordination among common types of trained or derived relations. Previous studies have been focused on within-domain analogy. The current study expands previous research by analyzing cross-domain analogy as relating relations among separate relational networks and by correlating participants' performance with a standard measure of analogical reasoning. In two experiments, adult participants first completed general intelligence and analogical reasoning tests. Subsequently, they were exposed to a computerized conditional discrimination training procedure designed to create two relational networks, each consisting of two 3-member equivalence classes. The critical test was a two-part analogical test in which participants had to relate combinatorial relations of coordination and distinction between the two relational networks. In Experiment 1, combinatorial relations for each network were individually tested prior to analogical testing, but in Experiment 2 they were not. Across both experiments, 65% of participants passed the analogical test on the first attempt. Moreover, results from the training procedure were strongly correlated with the standard measure of analogical reasoning. PMID:21547072

MENUMBUHKAN DAYA NALAR ( POWER OF REASON SISWA MELALUI PEMBELAJARAN ANALOGI MATEMATIKA

Directory of Open Access Journals (Sweden)

Rahayu Kariadinata

2012-02-01

Full Text Available Learning mathematical analogy is one alternative learning that can be applied in order to cultivate the power of reason (power of reason students. Through mathematical analogy students are required to be able to look for similarities or relationship nature of the two concepts are the same or different by comparison, then draw a conclusion from the similitude. Thus the analogy can be used as an explanation or as the basis of reasoning. Before starting the analogy of learning mathematics, teachers should examine the ability of understanding mathematical concepts of students, because of the level of understanding of students will affect the power of reason. Tasks (problems mathematical analogy included non-routine matter, therefore the required readiness of teachers to make it. In each question contained mathematical analogy same or different concepts, so it takes quite a lot of material. Steps to make about the mathematical analogy, are: a assemble all the concepts in mathematics student has learned; b Similarly stacking properties / relationships contained in any concept, and c select materials that have a nature / relationship analogous. In this paper is given two forms of matter of mathematical analogy is the analogy of mathematical models and mathematical analogy 1 models 2. Learning mathematical analogy should be carried out after a number of concepts learned. It is better to be given in classes end for many of the concepts that have been learned by the students. Reasoning power (power of reason the student becomes an important part in the process of learning to drive them toward their future as citizens are intelligent, which will be led by the power of reason (the brain and not by the strength (muscle only. As noted by former US President Thomas Jefferson (in Copi, 1978: vii, which states: "In a republican nation, Whose citizens are to be led by reason and persuasion and not by force, the art of reasoning Becomes of first importance"

Software approach to automatic patching of analog computer

Science.gov (United States)

1973-01-01

The Automatic Patching Verification program (APV) is described which provides the hybrid computer programmer with a convenient method of performing a static check of the analog portion of his study. The static check insures that the program is patched as specified, and that the computing components being used are operating correctly. The APV language the programmer uses to specify his conditions and interconnections is similar to the FORTRAN language in syntax. The APV control program reads APV source program statements from an assigned input device. Each source program statement is processed immediately after it is read. A statement may select an analog console, set an analog mode, set a potentiometer or DAC, or read from the analog console and perform a test. Statements are read and processed sequentially. If an error condition is detected, an output occurs on an assigned output device. When an end statement is read, the test is terminated.

An Experimentation Platform for On-Chip Integration of Analog Neural Networks: A Pathway to Trusted and Robust Analog/RF ICs.

Science.gov (United States)

Maliuk, Dzmitry; Makris, Yiorgos

2015-08-01

We discuss the design of an experimentation platform intended for prototyping low-cost analog neural networks for on-chip integration with analog/RF circuits. The objective of such integration is to support various tasks, such as self-test, self-tuning, and trust/aging monitoring, which require classification of analog measurements obtained from on-chip sensors. Particular emphasis is given to cost-efficient implementation reflected in: 1) low energy and area budgets of circuits dedicated to neural networks; 2) robust learning in presence of analog inaccuracies; and 3) long-term retention of learned functionality. Our chip consists of a reconfigurable array of synapses and neurons operating below threshold and featuring sub-μW power consumption. The synapse circuits employ dual-mode weight storage: 1) a dynamic mode, for fast bidirectional weight updates during training and 2) a nonvolatile mode, for permanent storage of learned functionality. We discuss a robust learning strategy, and we evaluate the system performance on several benchmark problems, such as the XOR2-6 and two-spirals classification tasks.

Dosimetry and stability studies of the boron neutron capture therapy agent F-BPA-Fr using PET and MRI

Science.gov (United States)

Dyke, Jonathan Paul

The treatment of deep seated brain tumors such as glioblastoma Multiforme has been unsuccessful for many patients. Surgical debulking, chemotherapy and standard radiotherapy have met with limited success. Boron neutron capture therapy offers a binary mode brachytherapy based on the following capture reaction that may provide an innovative alternative to standard forms of treatment:10B + n /to/ 11B /to 7Li + 4He + 2.31 MeVBoron is chemically attached to a tumor binding compound creating a non-toxic neutron absorber. A dose of epithermal neutrons provides the catalyst to produce the lithium and alpha particles which destroy any tissue within a length of one cell diameter from the boron compound. This dissertation uses 19F-MRI and 18F-PET to provide answers to the localization and biodistribution questions that arise in such a treatment modality. Practical patient dosimetry and actual treatment planning using the PET data is also examined. Finally, theoretical work done in the areas of compartmental modelling dealing with pharmacokinetic uptake of the PET radiotracer and dose analysis in microdosimetry is also presented.

Small Particles Intact Capture Experiment (SPICE)

Science.gov (United States)

Nishioka, Ken-Ji; Carle, G. C.; Bunch, T. E.; Mendez, David J.; Ryder, J. T.

1994-01-01

The Small Particles Intact Capture Experiment (SPICE) will develop technologies and engineering techniques necessary to capture nearly intact, uncontaminated cosmic and interplanetary dust particles (IDP's). Successful capture of such particles will benefit the exobiology and planetary science communities by providing particulate samples that may have survived unaltered since the formation of the solar system. Characterization of these particles may contribute fundamental data to our knowledge of how these particles could have formed into our planet Earth and, perhaps, contributed to the beginnings of life. The term 'uncontaminated' means that captured cosmic and IDP particles are free of organic contamination from the capture process and the term 'nearly intact capture' means that their chemical and elemental components are not materially altered during capture. The key to capturing cosmic and IDP particles that are organic-contamination free and nearly intact is the capture medium. Initial screening of capture media included organic foams, multiple thin foil layers, and aerogel (a silica gel); but, with the exception of aerogel, the requirements of no contamination or nearly intact capture were not met. To ensure no contamination of particles in the capture process, high-purity aerogel was chosen. High-purity aerogel results in high clarity (visual clearness), a useful quality in detection and recovery of embedded captured particles from the aerogel. P. Tsou at the Jet Propulsion Laboratory (JPL) originally described the use of aerogel for this purpose and reported laboratory test results. He has flown aerogel as a 'GAS-can Lid' payload on STS-47 and is evaluating the results. The Timeband Capture Cell Experiment (TICCE), a Eureca 1 experiment, is also flying aerogel and is scheduled for recovery in late April.

Beuchot’s formal analogism within Peter Singer’s philosophy

Directory of Open Access Journals (Sweden)

José Barrientos-Rastrojo

2015-01-01

Full Text Available This paper analyses an analogic reading of singerian ethics. Firstly, it studies Mauricio Beuchot’s analogical hermeneutics grounds. Then, it takes them to each of the Peter Singer’s ethical universes. Finally, it reveals the scheme of his ethic that will be followed in his future works. Therefore, this article has a prospective mission related to Professor Singer and it has an practical mission related to Mauricio Beuchot because it determines a practical performance to his analogical hermeneutics.

Laser capture microdissection: Arcturus(XT) infrared capture and UV cutting methods.

Science.gov (United States)

Gallagher, Rosa I; Blakely, Steven R; Liotta, Lance A; Espina, Virginia

2012-01-01

Laser capture microdissection (LCM) is a technique that allows the precise procurement of enriched cell populations from a heterogeneous tissue under direct microscopic visualization. LCM can be used to harvest the cells of interest directly or can be used to isolate specific cells by ablating the unwanted cells, resulting in histologically enriched cell populations. The fundamental components of laser microdissection technology are (a) visualization of the cells of interest via microscopy, (b) transfer of laser energy to a thermolabile polymer with either the formation of a polymer-cell composite (capture method) or transfer of laser energy via an ultraviolet laser to photovolatize a region of tissue (cutting method), and (c) removal of cells of interest from the heterogeneous tissue section. Laser energy supplied by LCM instruments can be infrared (810 nm) or ultraviolet (355 nm). Infrared lasers melt thermolabile polymers for cell capture, whereas ultraviolet lasers ablate cells for either removal of unwanted cells or excision of a defined area of cells. LCM technology is applicable to an array of applications including mass spectrometry, DNA genotyping and loss-of-heterozygosity analysis, RNA transcript profiling, cDNA library generation, proteomics discovery, and signal kinase pathway profiling. This chapter describes the unique features of the Arcturus(XT) laser capture microdissection instrument, which incorporates both infrared capture and ultraviolet cutting technology in one instrument, using a proteomic downstream assay as a model.

A dark business, full of shadows: analogy and theology in William Harvey.

Science.gov (United States)

Goldberg, Benjamin

2013-09-01

In a short work called De conceptione appended to the end of his Exercitationes de generatione animalium (1651), William Harvey developed a rather strange analogy. To explain how such marvelous productions as living beings were generated from the rather inauspicious ingredients of animal reproduction, Harvey argued that conception in the womb was like conception in the brain. It was mostly rejected at the time; it now seems a ludicrous theory based upon homonymy. However, this analogy offers insight into the structure and function of analogies in early modern natural philosophy. In this essay I hope to not only describe the complex nature of Harvey's analogy, but also offer a novel interpretation of his use of analogical reasoning, substantially revising the account offered by Guido Giglioni (1993). I discuss two points of conceptual change and negotiation in connection with Harvey's analogy, understanding it as both a confrontation between the border of the natural and the supernatural, as well as a moment in the history of psychology. My interpretation touches upon a number of important aspects, including why the analogy was rejected, how Harvey systematically deployed analogies according to his notions of natural philosophical method, how the analogy fits into contemporary discussions of analogies in science, and finally, how the analogy must be seen in the context of changing Renaissance notions of the science of the soul, ultimately confronting the problem of how to understand final causality in Aristotelian science. In connection with the last, I conclude the essay by turning to how Harvey embeds the analogy within a natural theological cosmology. Copyright © 2013. Published by Elsevier Ltd.

Membrane Affinity of Platensimycin and Its Dialkylamine Analogs

Directory of Open Access Journals (Sweden)

Ian Rowe

2015-08-01

Full Text Available Membrane permeability is a desired property in drug design, but there have been difficulties in quantifying the direct drug partitioning into native membranes. Platensimycin (PL is a new promising antibiotic whose biosynthetic production is costly. Six dialkylamine analogs of PL were synthesized with identical pharmacophores but different side chains; five of them were found inactive. To address the possibility that their activity is limited by the permeation step, we calculated polarity, measured surface activity and the ability to insert into the phospholipid monolayers. The partitioning of PL and the analogs into the cytoplasmic membrane of E. coli was assessed by activation curve shifts of a re-engineered mechanosensitive channel, MscS, in patch-clamp experiments. Despite predicted differences in polarity, the affinities to lipid monolayers and native membranes were comparable for most of the analogs. For PL and the di-myrtenyl analog QD-11, both carrying bulky sidechains, the affinity for the native membrane was lower than for monolayers (half-membranes, signifying that intercalation must overcome the lateral pressure of the bilayer. We conclude that the biological activity among the studied PL analogs is unlikely to be limited by their membrane permeability. We also discuss the capacity of endogenous tension-activated channels to detect asymmetric partitioning of exogenous substances into the native bacterial membrane and the different contributions to the thermodynamic force which drives permeation.

Overview of the Human Exploration Research Analog (HERA)

Science.gov (United States)

Neigut, J.

2015-01-01

In 2013, the Human Research Program at NASA began developing a new confinement analog specifically for conducting research to investigate the effects of confinement on the human system. The HERA (Human Exploration Research Analog) habitat has been used for both 7 and 14 day missions to date to examine and mitigate exploration risks to enable safe, reliable and productive human space exploration. This presentation will describe how the Flight Analogs Project developed the HERA facility and the infrastructure to suit investigator requirements for confinement research and in the process developed a new approach to analog utilization and a new state of the art analog facility. Details regarding HERA operations will be discussed including specifics on the mission simulation utilized for the current 14-day campaign, the specifics of the facility (total volume, overall size, hardware), and the capabilities available to researchers. The overall operational philosophy, mission fidelity including timeline, schedule pressures and cadence, and development and implementation of mission stressors will be presented. Research conducted to date in the HERA has addressed risks associated with behavioral health and performance, human physiology, as well as human factors. This presentation will conclude with a discussion of future research plans for the HERA, including infrastructure improvements and additional research capabilities planned for the upcoming 30-day missions in 2016.

Reasoning through Instructional Analogies

Science.gov (United States)

Kapon, Shulamit; diSessa, Andrea A.

2012-01-01

This article aims to account for students' assessments of the plausibility and applicability of analogical explanations, and individual differences in these assessments, by analyzing properties of students' underlying knowledge systems. We developed a model of explanation and change in explanation focusing on knowledge elements that provide a…

Radioprotective agents to reduce BNCT (Boron Neutron Capture Therapy) induced mucositis in the hamster cheek pouch

International Nuclear Information System (INIS)

Monti Hughes, A.; Pozzi, E.C.C.; Thorp, S.

2013-01-01

Introduction: BNCT is based on the capture reaction between boron, selectively targeted to tumor tissue, and thermal neutrons which gives rise to lethal, short-range high linear energy transfer particles that selectively damage tumor tissue, sparing normal tissue. We previously evidenced a remarkable therapeutic success of BNCT mediated by boronophenylalanine (BPA) in the hamster cheek pouch oral cancer and pre cancer model. Despite therapeutic efficacy, mucositis induced in premalignant tissue was dose limiting and favored, in some cases, tumor development. In a clinical scenario, oral mucositis limits the dose administered to head and neck tumors. Aim: Our aim was to evaluate the effect of the administration of different radioprotective agents, seeking to reduce BNCT-induced mucositis to acceptable levels in dose-limiting premalignant tissue; without compromising therapeutic effect evaluated as inhibition on tumor development in premalignant tissue; without systemic or local side effects; and without negative effects on the biodistribution of the boron compound used for treatment. Materials and methods: Cancerized hamsters with DMBA (dimethylbenzanthracene) were treated with BPA-BNCT 5 Gy total absorbed dose to premalignant tissue, at the RA-3 Nuclear Reactor, divided into different groups: 1-treated with FLUNIXIN; 2- ATORVASTATIN; 3-THALIDOMIDE; 4-HISTAMINE (two concentrations: Low -1 mg/ml- and High -5 mg/ml-); 5-JNJ7777120; 6-JNJ10191584; 7-SALINE (vehicle). Cancerized animals without any treatment (neither BNCT nor radioprotective therapy) were also analyzed. We followed the animals during one month and evaluated the percentage of animals with unacceptable/severe mucositis, clinical status and percentage of animals with new tumors post treatment. We also performed a preliminary biodistribution study of BPA + Histamine “low” concentration to evaluate the potential effect of the radioprotector on BPA biodistribution. Results: Histamine �

The problem of latent attentional capture: Easy visual search conceals capture by task-irrelevant abrupt onsets.

Science.gov (United States)

Gaspelin, Nicholas; Ruthruff, Eric; Lien, Mei-Ching

2016-08-01

Researchers are sharply divided regarding whether irrelevant abrupt onsets capture spatial attention. Numerous studies report that they do and a roughly equal number report that they do not. This puzzle has inspired numerous attempts at reconciliation, none gaining general acceptance. The authors propose that abrupt onsets routinely capture attention, but the size of observed capture effects depends critically on how long attention dwells on distractor items which, in turn, depends critically on search difficulty. In a series of spatial cuing experiments, the authors show that irrelevant abrupt onsets produce robust capture effects when visual search is difficult, but not when search is easy. Critically, this effect occurs even when search difficulty varies randomly across trials, preventing any strategic adjustments of the attentional set that could modulate probability of capture by the onset cue. The authors argue that easy visual search provides an insensitive test for stimulus-driven capture by abrupt onsets: even though onsets truly capture attention, the effects of capture can be latent. This observation helps to explain previous failures to find capture by onsets, nearly all of which used an easy visual search. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

Pentafluorobenzyl bromide-A versatile derivatization agent in chromatography and mass spectrometry: I. Analysis of inorganic anions and organophosphates.

Science.gov (United States)

Tsikas, Dimitrios

2017-02-01

Pentafluorobenzyl bromide (PFB-Br) is a versatile derivatization agent. It is widely used in chromatography and mass spectrometry since several decades. The bromide atom is largely the single leaving group of PFB-Br. It is substituted by wide a spectrum of nucleophiles in aqueous and non-aqueous systems to form electrically neutral, in most organic solvents soluble, generally thermally stable, volatile, strongly electron-capturing and ultraviolet light-absorbing derivatives. Because of these greatly favoured physicochemical properties, PFB-Br emerged an ideal derivatization agent for highly sensitive analysis of endogenous and exogenous substances including various inorganic and organic anions by electron capture detection or after electron-capture negative-ion chemical ionization in GC-MS. The present article attempts an appraisal of the utility of PFB-Br in analytical chemistry. It reviews and discusses papers dealing with the use of PFB-Br as the derivatization reagent in the qualitative and quantitative analysis of endogenous and exogenous inorganic anions in various biological samples, notably plasma, urine and saliva. These analytes include nitrite, nitrate, cyanide and dialkyl organophosphates. Special emphasis is given to mass spectrometry-based approaches and stable-isotope dilution techniques. Copyright © 2016 Elsevier B.V. All rights reserved.

Study on keV-neutron capture cross sections and capture γ-ray spectra of 117,119Sn

International Nuclear Information System (INIS)

Nishiyama, J.; Igashira, M.; Ohsaki, T.; Kim, G.N.; Chung, W.C.; Ro, T.I.

2006-01-01

The capture cross sections and capture γ-ray spectra of 117,119 Sn were measured in an incident neutron energy region from 10 to 100 keV and at 570 keV, using a 1.5-ns pulsed neutron source by the 7 Li(p,n) 7 Be reaction and a large anti-Compton NaI(Tl) γ-ray spectrometer. A pulse-height weighting technique was applied to observed capture γ-ray pulse-height spectra to derive capture yields. The capture cross sections of 117,119 Sn were obtained with the error of about 5% by using the standard capture cross sections of 197 Au. The present cross sections were compared with previous experimental data and the evaluated values in JENDL-3.3 and ENDF/B-VI. The capture γ-ray spectra of 117,119 Sn were derived by unfolding the observed capture γ-ray pulse-height spectra. The calculations of capture cross sections and capture γ-ray spectra of 117,119 Sn were performed with the EMPIRE-II code. The calculated results were compared with the present experimental ones. (author)

Albert Einstein, Analogizer Extraordinaire

CERN Multimedia

CERN. Geneva

2007-01-01

Where does deep insight in physics come from? It is tempting to think that it comes from the purest and most precise of reasoning, following ironclad laws of thought that compel the clear mind completely rigidly. And yet the truth is quite otherwise. One finds, when one looks closely at any major discovery, that the greatest of physicists are, in some sense, the most crazily daring and irrational of all physicists. Albert Einstein exemplifies this thesis in spades. In this talk I will describe the key role, throughout Albert Einstein's fabulously creative life, played by wild guesses made by analogy lacking any basis whatsoever in pure reasoning. In particular, in this year of 2007, the centenary of 1907, I will describe how over the course of two years (1905 through 1907) of pondering, Einstein slowly came, via analogy, to understand the full, radical consequences of the equation that he had first discovered and published in 1905, arguably the most famous equation of all time: E = mc2.

Analog-to-digital conversion

CERN Document Server

Pelgrom, Marcel

2017-01-01

This textbook is appropriate for use in graduate-level curricula in analog-to-digital conversion, as well as for practicing engineers in need of a state-of-the-art reference on data converters. It discusses various analog-to-digital conversion principles, including sampling, quantization, reference generation, nyquist architectures and sigma-delta modulation. This book presents an overview of the state of the art in this field and focuses on issues of optimizing accuracy and speed, while reducing the power level. This new, third edition emphasizes novel calibration concepts, the specific requirements of new systems, the consequences of 22-nm technology and the need for a more statistical approach to accuracy. Pedagogical enhancements to this edition include additional, new exercises, solved examples to introduce all key, new concepts and warnings, remarks and hints, from a practitioner’s perspective, wherever appropriate. Considerable background information and practical tips, from designing a PCB, to lay-o...

Analog-to-digital conversion

CERN Document Server

Pelgrom, Marcel J. M

2013-01-01

This textbook is appropriate for use in graduate-level curricula in analog to digital conversion, as well as for practicing engineers in need of a state-of-the-art reference on data converters.  It discusses various analog-to-digital conversion principles, including sampling, quantization, reference generation, nyquist architectures and sigma-delta modulation.  This book presents an overview of the state-of-the-art in this field and focuses on issues of optimizing accuracy and speed, while reducing the power level. This new, second edition emphasizes novel calibration concepts, the specific requirements of new systems, the consequences of 45-nm technology and the need for a more statistical approach to accuracy.  Pedagogical enhancements to this edition include more than twice the exercises available in the first edition, solved examples to introduce all key, new concepts and warnings, remarks and hints, from a practitioner’s perspective, wherever appropriate.  Considerable background information and pr...

Terrestrial Spaceflight Analogs: Antarctica

Science.gov (United States)

Crucian, Brian

2013-01-01

Alterations in immune cell distribution and function, circadian misalignment, stress and latent viral reactivation appear to persist during Antarctic winterover at Concordia Station. Some of these changes are similar to those observed in Astronauts, either during or immediately following spaceflight. Others are unique to the Concordia analog. Based on some initial immune data and environmental conditions, Concordia winterover may be an appropriate analog for some flight-associated immune system changes and mission stress effects. An ongoing smaller control study at Neumayer III will address the influence of the hypoxic variable. Changes were observed in the peripheral blood leukocyte distribution consistent with immune mobilization, and similar to those observed during spaceflight. Alterations in cytokine production profiles were observed during winterover that are distinct from those observed during spaceflight, but potentially consistent with those observed during persistent hypobaric hypoxia. The reactivation of latent herpesviruses was observed during overwinter/isolation, that is consistently associated with dysregulation in immune function.

Phospholipid ether analogs for the detection of colorectal tumors.

Directory of Open Access Journals (Sweden)

Dustin A Deming

Full Text Available The treatment of localized colorectal cancer (CRC depends on resection of the primary tumor with adequate margins and sufficient lymph node sampling. A novel imaging agent that accumulates in CRCs and the associated lymph nodes is needed. Cellectar Biosciences has developed a phospholipid ether analog platform that is both diagnostic and therapeutic. CLR1502 is a near-infrared fluorescent molecule, whereas 124/131I-CLR1404 is under clinical investigation as a PET tracer/therapeutic agent imaged by SPECT. We investigated the use of CLR1502 for the detection of intestinal cancers in a murine model and 131I-CLR1404 in a patient with metastatic CRC. Mice that develop multiple intestinal tumors ranging from adenomas to locally advanced adenocarcinomas were utilized. After 96 hours post CLR1502 injection, the intestinal tumors were analyzed using a Spectrum IVIS (Perkin Elmer and a Fluobeam (Fluoptics. The intensity of the fluorescent signal was correlated with the histological characteristics for each tumor. Colon adenocarcinomas demonstrated increased accumulation of CLR1502 compared to non-invasive lesions (total radiant efficiency: 1.76×10(10 vs 3.27×10(9 respectively, p = 0.006. Metastatic mesenteric tumors and uninvolved lymph nodes were detected with CLR1502. In addition, SPECT imaging with 131I-CLR1404 was performed as part of a clinical trial in patients with advanced solid tumors. 131I-CLR1404 was shown to accumulate in metastatic tumors in a patient with colorectal adenocarcinoma. Together, these compounds might enhance our ability to properly resect CRCs through better localization of the primary tumor and improved lymph node identification as well as detect distant disease.

The Development of Verbal Relations in Analogical Reasonings.

Science.gov (United States)

Sternberg, Robert J.; Nigro, Georgia

A six-process theory of analogical reasoning was tested by administering verbal analogy items to students in grades 3 through college. The items were classified according to five verbal relations: synonyms, antonyms, functional, linear ordering, and class membership. A new method of componential analysis that does not require precueing was used to…

Using Analogies to Prevent Misconceptions about Chemical Equilibrium

Science.gov (United States)

Sahin Pekmez, Esin

2010-01-01

The main purpose of this study was to find the effectiveness of using analogies to prevent misconceptions about chemical equilibrium. Nineteen analogies, which were based on dynamic aspects of chemical equilibrium and application of Le Chatelier's principle, were developed. The participations of this study consisted of 11th grade students (n: 151)…

A Chemically Synthesized Capture Agent Enables the Selective, Sensitive, and Robust Electrochemical Detection of Anthrax Protective Antigen

Science.gov (United States)

2014-08-01

Electrochemical Oxidation of Catechol and Para - Aminophenol Esters in the Presence of Hydrolases. Bioelectrochem. Bioenerg. 1980, 7, 11–24. 26. Evans-Nguyen, K. M...platform. Analytical HPLC (a) and MALDI-TOF (b) traces of biligand capture agentwithno thermal treatment, and after 5 days of storage as a powder at...sample of biligand was stored for 5 days at 65 C under nitrogen atmosphere. Analy- tical HPLC traces (Figure 4a) andMALDI-TOF (Figure 4b) reveal

Analysis of Recurrent Analog Neural Networks

Directory of Open Access Journals (Sweden)

Z. Raida

1998-06-01

Full Text Available In this paper, an original rigorous analysis of recurrent analog neural networks, which are built from opamp neurons, is presented. The analysis, which comes from the approximate model of the operational amplifier, reveals causes of possible non-stable states and enables to determine convergence properties of the network. Results of the analysis are discussed in order to enable development of original robust and fast analog networks. In the analysis, the special attention is turned to the examination of the influence of real circuit elements and of the statistical parameters of processed signals to the parameters of the network.

Analogy Mapping Development for Learning Programming

Science.gov (United States)

Sukamto, R. A.; Prabawa, H. W.; Kurniawati, S.

2017-02-01

Programming skill is an important skill for computer science students, whereas nowadays, there many computer science students are lack of skills and information technology knowledges in Indonesia. This is contrary with the implementation of the ASEAN Economic Community (AEC) since the end of 2015 which is the qualified worker needed. This study provided an effort for nailing programming skills by mapping program code to visual analogies as learning media. The developed media was based on state machine and compiler principle and was implemented in C programming language. The state of every basic condition in programming were successful determined as analogy visualization.

99mTc labeled VIP analog: evaluation for imaging colorectal cancer

International Nuclear Information System (INIS)

Rao, P.S.; Thakur, M.L.; Pallela, V.; Patti, R.; Reddy, K.; Li, H.; Sharma, S.; Pham, H.L.; Diggles, L.; Minami, C.; Marcus, C.S.

2001-01-01

Early and reliable diagnosis of colorectal cancer continues to be demanding and challenging. Colorectal cancer cells express Vasoactive Intestinal Peptide (VIP) receptors in high density. We have prepared a VIP analog (TP3654), labeled it with 99m Tc, and evaluated it in experimental animals as an agent for imaging colorectal cancer. The tissue distribution of 99m Tc-TP3654 has been compared with that of 111 In-DTPA-Octreotide and 99m Tc-anti-CEA scan in nude mice bearing human colorectal cancer LS174T. Finally, pharmacokinetic and tissue distribution studies of 99m Tc-TP3654 have been performed in four normal human volunteers. Data suggest that 99m Tc-TP3654 can be prepared efficiently without loss of its receptor specificity and biological activity. Although the 24 hr tumor uptake of 99m Tc-TP3654 in the animal model used was modest (0.21 ± 0.07% I.D./g), the tissue distribution profile was more favorable than that of 111 In-DTPA-Octreotide or 99m Tc-anti-CEA scan. Human studies indicated that 99m Tc-TP3654 had no adverse effect in any subject. Within 24 hours, approximately 70% of the injected dose cleared through the kidneys, and approximately 20% through the hepatobiliary system. In these non-fasting volunteers hepatobiliary clearance was slow and in cancer patients tumor uptake was rapid. Data suggest that 99m Tc-TP3654 is a promising agent for imaging colorectal cancer

Analogical study of the servo-control of a reactivity modulator

International Nuclear Information System (INIS)

Le Bot, Michel

1969-03-01

In the context of the study of the transfer functions related to the Cabri reactor, this paper presents: the objective of the servo-control (reactivity modulator, reasons for the analogical study), the principles of the servo-control (description of the servo-controlled system, elaboration of the error signal, principles of the phase meter, critical analysis of different types of phase meters), the analogical formulation (transfer diagram of the process, analogical simulation of the process, analogical realization of the phase meter, simulation of the Low Frequency generator), study of the controlled system and results (system responses to echelon and ramp signals, responses of the controlled system with the phase meter in feedback)

VME Switch for CERN's PS Analog Video System

CERN Document Server

Acebes, I; Heinze, W; Lewis, J; Serrano, J

2003-01-01

Analog video signal switching is used in CERN's Proton Synchrotron (PS) complex to route the video signals coming from Beam Diagnostics systems to the Meyrin Control Room (MCR). Traditionally, this has been done with custom electromechanical relay-based cards controlled serially via CAMAC crates. In order to improve the robustness and maintainability of the system, while keeping it analog to preserve the low latency, a VME card based on Analog Devices' AD8116 analog matrix chip has been developed. Video signals go into the front panel and exit the switch through the P2 connector of the VME backplane. The module is a 16 input, 32 output matrix. Larger matrices can be built using more modules and bussing their outputs together, thanks to the high impedance feature of the AD8116. Another VME module takes the selected signals from the P2 connector and performs automatic gain to send them at nominal output level through its front panel. This paper discusses both designs and presents experimental test results.

Analogical reasoning in a capuchin monkey (Cebus apella).

Science.gov (United States)

Kennedy, Erica Hoy; Fragaszy, Dorothy M

2008-05-01

Previous evidence has suggested that analogical reasoning (recognizing similarities among object relations when the objects themselves are dissimilar) is limited to humans and apes. This study investigated whether capuchin monkeys (Cebus apella) can use analogical reasoning to solve a 3-dimensional search task. The task involved hiding a food item under 1 of 2 or 3 plastic cups of different sizes and then allowing subjects to search for food hidden under the cup of analogous size in their own set of cups. Four monkeys were exposed to a series of relational matching tasks. If subjects reached criterion on these tasks, they were exposed to relational transfer tasks involving novel stimuli. Three of the monkeys failed to reach criterion on the basic relational matching tasks and therefore were not tested further. One monkey, however, revealed above-chance performance on a series of transfer tasks with 3 novel stimuli. This evidence suggests that contrary to previous arguments, a member of a New World monkey species can solve an analogical problem. PsycINFO Database Record (c) 2008 APA, all rights reserved.

Community Decadal Panel for Terrestrial Analogs to Mars

Science.gov (United States)

Barlow, N. G.; Farr, T.; Baker, V. R.; Bridges, N.; Carsey, F.; Duxbury, N.; Gilmore, M. S.; Green, J. R.; Grin, E.; Hansen, V.; Keszthelyi, L.; Lanagan, P.; Lentz, R.; Marinangeli, L.; Morris, P. A.; Ori, G. G.; Paillou, P.; Robinson, C.; Thomson, B.

2001-11-01

It is well recognized that interpretations of Mars must begin with the Earth as a reference. The most successful comparisons have focused on understanding geologic processes on the Earth well enough to extrapolate to Mars' environment. Several facets of terrestrial analog studies have been pursued and are continuing. These studies include field workshops, characterization of terrestrial analog sites for Mars, instrument tests, laboratory measurements (including analysis of martian meteorites), and computer and laboratory modeling. The combination of all these activities allows scientists to constrain the processes operating in specific terrestrial environments and extrapolate how similar processes could affect Mars. The Terrestrial Analogs for Mars Community Panel is considering the following two key questions: (1) How do terrestrial analog studies tie in to the MEPAG science questions about life, past climate, and geologic evolution of Mars, and (2) How can future instrumentation be used to address these questions. The panel is considering the issues of data collection, value of field workshops, data archiving, laboratory measurements and modeling, human exploration issues, association with other areas of solar system exploration, and education and public outreach activities.

Antimicrobial and cell-penetrating properties of penetratin analogs

DEFF Research Database (Denmark)

Bahnsen, Jesper Søborg; Franzyk, Henrik; Sandberg-Schaal, Anne

2013-01-01

Cell-penetrating peptides (CPPs) and antimicrobial peptides (AMPs) show great potential as drug delivery vectors and new antibiotic drug entities, respectively. The current study deals with the properties of a variety of peptide analogs derived from the well-known CPP penetratin as well as octaar......Cell-penetrating peptides (CPPs) and antimicrobial peptides (AMPs) show great potential as drug delivery vectors and new antibiotic drug entities, respectively. The current study deals with the properties of a variety of peptide analogs derived from the well-known CPP penetratin as well...... as octaarginine and different Tat sequences. The effects of peptide length, guanidinium content, and sequence of non-cationic residues were assessed in mammalian and bacterial cells. The arginine (Arg) content in the penetratin analogs was found to influence eukaryotic cell uptake efficiency, antimicrobial...... was similar, the eukaryotic cellular uptake of the shuffled analogs was noticeably lower than for native penetratin. Moreover, a point substitution of Met to Leu in native penetratin had no influence on eukaryotic cellular uptake and antimicrobial effect, and only a minor effect on cytotoxicity, in contrast...

The use of analogies in forecasting ecological and societal responses to global warming

Energy Technology Data Exchange (ETDEWEB)

Glantz, M.H. (National Center for Atmospheric Research, Boulder CO (USA). Environmental Research and Societal Impacts Group)

1991-06-01

Due to the limitations of general circulation models, researchers use analogies to look at future climatic change and its effects. Analogies used include the greenhouse, the Altithermal period, regional climates and summertime. Analogical reasoning is a prominent part of general circulation modeling of the atmosphere. Analogies are useful for generating hypotheses and improving understanding, but not as forecasts. The use of an analogy to develop specific policies related to global warming is risky. Historical analogies can provide a first approach to ascertaining the level of societal preparedness for the impacts of a global warming. Each analogy provides additional information about the target problem. 63 refs., 3 figs., 1 tab.

The use of analogies in forecasting ecological and societal responses to global warming

International Nuclear Information System (INIS)

Glantz, M.H.

1991-01-01

Due to the limitations of general circulation models, researchers use analogies to look at future climatic change and its effects. Analogies used include the greenhouse, the Altithermal period, regional climates and summertime. Analogical reasoning is a prominent part of general circulation modeling of the atmosphere. Analogies are useful for generating hypotheses and improving understanding, but not as forecasts. The use of an analogy to develop specific policies related to global warming is risky. Historical analogies can provide a first approach to ascertaining the level of societal preparedness for the impacts of a global warming. Each analogy provides additional information about the target problem. 63 refs., 3 figs., 1 tab

Electrostatic analogy for symmetron gravity

Science.gov (United States)

Ogden, Lillie; Brown, Katherine; Mathur, Harsh; Rovelli, Kevin

2017-12-01

The symmetron model is a scalar-tensor theory of gravity with a screening mechanism that suppresses the effect of the symmetron field at high densities characteristic of the Solar System and laboratory scales but allows it to act with gravitational strength at low density on the cosmological scale. We elucidate the screening mechanism by showing that in the quasistatic Newtonian limit there are precise analogies between symmetron gravity and electrostatics for both strong and weak screening. For strong screening we find that large dense bodies behave in a manner analogous to perfect conductors in electrostatics. Based on this analogy we find that the symmetron field exhibits a lightning rod effect wherein the field gradients are enhanced near the ends of pointed or elongated objects. An ellipsoid placed in a uniform symmetron gradient is shown to experience a torque. By symmetry there is no gravitational torque in this case. Hence this effect unmasks the symmetron and might serve as the basis for future laboratory experiments. The symmetron force between a point mass and a large dense body includes a component corresponding to the interaction of the point mass with its image in the larger body. None of these effects have counterparts in the Newtonian limit of Einstein gravity. We discuss the similarities between symmetron gravity and the chameleon model as well as the differences between the two.

Introduction to engineering a starter's guide with hands-on analog multimedia explorations

CERN Document Server

Karam, Lina

2008-01-01

This lecture provides a hands-on glimpse of the field of electrical engineering. The introduced applications utilize the NI ELVIS hardware and software platform to explore concepts such as circuits, power, analog sensing, and introductory analog signal processing such as signal generation, analog filtering, and audio and music processing. These principals and technologies are introduced in a very practical way and are fundamental to many of the electronic devices we use today. Some examples include photodetection, analog signal (audio, light, temperature) level meter, and analog music equalize

The Description of Problems Relating to Analogies Used in Science and Technology Textbooks

Directory of Open Access Journals (Sweden)

Rahmi YAĞBASAN

2008-01-01

Full Text Available The aim of this study was to determine the problems concerning the use of analogies ingeneral and analogies used in primary school science and technology lessons inparticular. In this study, descriptive method was used. 4th, 5th, and 8th classes Scienceand Technology course books; 7 th, 8 th classes Science Books were used as a source.Analogies in the course books were classified according to the literature and theproblems found related to the analogies are pointed out in the study. In this study itwas seen that eighty-nine analogies were used in Science and Technology and inScience course books. These analogies were used in descending order as 8, 4, 6, 7, 5class groups. Also it was seen that these analogies were generally at simple andpictorial analogies.

Marker-Free Human Motion Capture

DEFF Research Database (Denmark)

Grest, Daniel

Human Motion Capture is a widely used technique to obtain motion data for animation of virtual characters. Commercial optical motion capture systems are marker-based. This book is about marker-free motion capture and its possibilities to acquire motion from a single viewing direction. The focus...

Associative memory in an analog iterated-map neural network

Science.gov (United States)

Marcus, C. M.; Waugh, F. R.; Westervelt, R. M.

1990-03-01

The behavior of an analog neural network with parallel dynamics is studied analytically and numerically for two associative-memory learning algorithms, the Hebb rule and the pseudoinverse rule. Phase diagrams in the parameter space of analog gain β and storage ratio α are presented. For both learning rules, the networks have large ``recall'' phases in which retrieval states exist and convergence to a fixed point is guaranteed by a global stability criterion. We also demonstrate numerically that using a reduced analog gain increases the probability of recall starting from a random initial state. This phenomenon is comparable to thermal annealing used to escape local minima but has the advantage of being deterministic, and therefore easily implemented in electronic hardware. Similarities and differences between analog neural networks and networks with two-state neurons at finite temperature are also discussed.

Advances in analog and RF IC design for wireless communication systems

CERN Document Server

Manganaro, Gabriele

2013-01-01

Advances in Analog and RF IC Design for Wireless Communication Systems gives technical introductions to the latest and most significant topics in the area of circuit design of analog/RF ICs for wireless communication systems, emphasizing wireless infrastructure rather than handsets. The book ranges from very high performance circuits for complex wireless infrastructure systems to selected highly integrated systems for handsets and mobile devices. Coverage includes power amplifiers, low-noise amplifiers, modulators, analog-to-digital converters (ADCs) and digital-to-analog converters

Some aspects of analogical reasoning in mathematical creativity

OpenAIRE

Pease, Alison; Guhe, Markus; Smaill, Alan

2010-01-01

Analogical reasoning can shed light on both of the two key processes of creativity– generation and evaluation. Hence, it is a powerful tool for creativity. We illustrate this with three historical case studies of creative mathematical conjectures which were either found or evaluated via analogies. We conclude by describing our ongoing efforts to build computational realisations of these ideas.

Analogies as Creative Inspiration Sources in the Design Studio : The Teamwork

NARCIS (Netherlands)

Casakin, H.; Van Timmeren, A.

2014-01-01

Analogical reasoning can be seen as an important aid in problem solving, and architectural design problem solving in particular. Analogical reasoning was found to be an important aid supporting architectural education. In this paper we explored the use of visual and verbal analogies in the early

C–H-Functionalization logic guides the synthesis of a carbacyclopamine analog

Directory of Open Access Journals (Sweden)

Sebastian Rabe

2014-07-01

Full Text Available The chemical synthesis of carbacyclopamine analog 2, a cyclopamine analog with an all-carbon E-ring, is reported. The use of C–H-functionalization logic and further metal-catalyzed transformations allows for a concise entry to this new class of acid-stable cyclopamine analogs.

Analogy as a strategy for supporting complex problem solving under uncertainty.

Science.gov (United States)

Chan, Joel; Paletz, Susannah B F; Schunn, Christian D

2012-11-01

Complex problem solving in naturalistic environments is fraught with uncertainty, which has significant impacts on problem-solving behavior. Thus, theories of human problem solving should include accounts of the cognitive strategies people bring to bear to deal with uncertainty during problem solving. In this article, we present evidence that analogy is one such strategy. Using statistical analyses of the temporal dynamics between analogy and expressed uncertainty in the naturalistic problem-solving conversations among scientists on the Mars Rover Mission, we show that spikes in expressed uncertainty reliably predict analogy use (Study 1) and that expressed uncertainty reduces to baseline levels following analogy use (Study 2). In addition, in Study 3, we show with qualitative analyses that this relationship between uncertainty and analogy is not due to miscommunication-related uncertainty but, rather, is primarily concentrated on substantive problem-solving issues. Finally, we discuss a hypothesis about how analogy might serve as an uncertainty reduction strategy in naturalistic complex problem solving.

Stimulus-driven capture and contingent capture

NARCIS (Netherlands)

Theeuwes, J.; Olivers, C.N.L.; Belopolsky, A.V.

2010-01-01

Whether or not certain physical events can capture attention has been one of the most debated issues in the study of attention. This discussion is concerned with how goal-directed and stimulus-driven processes interact in perception and cognition. On one extreme of the spectrum is the idea that

Analogical processes in children's understanding of spatial representations.

Science.gov (United States)

Yuan, Lei; Uttal, David; Gentner, Dedre

2017-06-01

We propose that map reading can be construed as a form of analogical mapping. We tested 2 predictions that follow from this claim: First, young children's patterns of performance in map reading tasks should parallel those found in analogical mapping tasks; and, second, children will benefit from guided alignment instructions that help them see the relational correspondences between the map and the space. In 4 experiments, 3-year-olds completed a map reading task in which they were asked to find hidden objects in a miniature room, using a corresponding map. We manipulated the availability of guided alignment (showing children the analogical mapping between maps and spaces; Experiments 1, 2, and 3a), the format of guided alignment (gesture or relational language; Experiment 2), and the iconicity of maps (Experiments 3a and 3b). We found that (a) young children's difficulties in map reading follow from known patterns of analogical development-for example, focusing on object similarity over relational similarity; and (b) guided alignment based on analogical reasoning led to substantially better performance. Results also indicated that children's map reading performance was affected by the format of guided alignment, the iconicity of the maps, and the order of tasks. The results bear on the developmental mechanisms underlying young children's learning of spatial representations and also suggest ways to support this learning. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Anti-inflammatory effects of α-galactosylceramide analogs in activated microglia: involvement of the p38 MAPK signaling pathway.

Directory of Open Access Journals (Sweden)

Yeon-Hui Jeong

Full Text Available Microglial activation plays a pivotal role in the development and progression of neurodegenerative diseases. Thus, anti-inflammatory agents that control microglial activation can serve as potential therapeutic agents for neurodegenerative diseases. Here, we designed and synthesized α-galactosylceramide (α-GalCer analogs to exert anti-inflammatory effects in activated microglia. We performed biological evaluations of 25 α-GalCer analogs and observed an interesting preliminary structure-activity relationship in their inhibitory influence on NO release and TNF-α production in LPS-stimulated BV2 microglial cells. After identification of 4d and 4e as hit compounds, we further investigated the underlying mechanism of their anti-inflammatory effects using RT-PCR analysis. We confirmed that 4d and 4e regulate the expression of iNOS, COX-2, IL-1β, and IL-6 at the mRNA level and the expression of TNF-α at the post-transcriptional level. In addition, both 4d and 4e inhibited LPS-induced DNA binding activities of NF-κB and AP-1 and phosphorylation of p38 MAPK without affecting other MAP kinases. When we examined the anti-inflammatory effect of a p38 MAPK-specific inhibitor, SB203580, on microglial activation, we observed an identical inhibitory pattern as that of 4d and 4e, not only on NO and TNF-α production but also on the DNA binding activities of NF-κB and AP-1. Taken together, these results suggest that p38 MAPK plays an important role in the anti-inflammatory effects of 4d and 4e via the modulation of NF-κB and AP-1 activities.

A model to capture and manage tacit knowledge using a multiagent system

Science.gov (United States)

Paolino, Lilyam; Paggi, Horacio; Alonso, Fernando; López, Genoveva

2014-10-01

This article presents a model to capture and register business tacit knowledge belonging to different sources, using an expert multiagent system which enables the entry of incidences and captures the tacit knowledge which could fix them. This knowledge and their sources are evaluated through the application of trustworthy algorithms that lead to the registration of the data base and the best of each of them. Through its intelligent software agents, this system interacts with the administrator, users, with the knowledge sources and with all the practice communities which might exist in the business world. The sources as well as the knowledge are constantly evaluated, before being registered and also after that, in order to decide the staying or modification of its original weighting. If there is the possibility of better, new knowledge are registered through the old ones. This is also part of an investigation being carried out which refers to knowledge management methodologies in order to manage tacit business knowledge so as to make the business competitiveness easier and leading to innovation learning.

IADE: a system for intelligent automatic design of bioisosteric analogs

Science.gov (United States)

Ertl, Peter; Lewis, Richard

2012-11-01

IADE, a software system supporting molecular modellers through the automatic design of non-classical bioisosteric analogs, scaffold hopping and fragment growing, is presented. The program combines sophisticated cheminformatics functionalities for constructing novel analogs and filtering them based on their drug-likeness and synthetic accessibility using automatic structure-based design capabilities: the best candidates are selected according to their similarity to the template ligand and to their interactions with the protein binding site. IADE works in an iterative manner, improving the fitness of designed molecules in every generation until structures with optimal properties are identified. The program frees molecular modellers from routine, repetitive tasks, allowing them to focus on analysis and evaluation of the automatically designed analogs, considerably enhancing their work efficiency as well as the area of chemical space that can be covered. The performance of IADE is illustrated through a case study of the design of a nonclassical bioisosteric analog of a farnesyltransferase inhibitor—an analog that has won a recent "Design a Molecule" competition.

Componential Analysis of Analogical-Reasoning Performance of High and Low Achievers.

Science.gov (United States)

Armour-Thomas, Eleanor; Allen, Brenda A.

1990-01-01

Assessed analogical reasoning in high- and low-achieving students at the high school level and determined whether analogical reasoning was related to academic achievement in ninth grade students (N=54). Results indicated that high achievers performed better than low achievers on all types of analogical-reasoning processes. (Author/ABL)

On Modeling Large-Scale Multi-Agent Systems with Parallel, Sequential and Genuinely Asynchronous Cellular Automata

International Nuclear Information System (INIS)

Tosic, P.T.

2011-01-01

We study certain types of Cellular Automata (CA) viewed as an abstraction of large-scale Multi-Agent Systems (MAS). We argue that the classical CA model needs to be modified in several important respects, in order to become a relevant and sufficiently general model for the large-scale MAS, and so that thus generalized model can capture many important MAS properties at the level of agent ensembles and their long-term collective behavior patterns. We specifically focus on the issue of inter-agent communication in CA, and propose sequential cellular automata (SCA) as the first step, and genuinely Asynchronous Cellular Automata (ACA) as the ultimate deterministic CA-based abstract models for large-scale MAS made of simple reactive agents. We first formulate deterministic and nondeterministic versions of sequential CA, and then summarize some interesting configuration space properties (i.e., possible behaviors) of a restricted class of sequential CA. In particular, we compare and contrast those properties of sequential CA with the corresponding properties of the classical (that is, parallel and perfectly synchronous) CA with the same restricted class of update rules. We analytically demonstrate failure of the studied sequential CA models to simulate all possible behaviors of perfectly synchronous parallel CA, even for a very restricted class of non-linear totalistic node update rules. The lesson learned is that the interleaving semantics of concurrency, when applied to sequential CA, is not refined enough to adequately capture the perfect synchrony of parallel CA updates. Last but not least, we outline what would be an appropriate CA-like abstraction for large-scale distributed computing insofar as the inter-agent communication model is concerned, and in that context we propose genuinely asynchronous CA. (author)

Safety comparison of additives in antiglaucoma prostaglandin (PG analog ophthalmic formulations

Directory of Open Access Journals (Sweden)

Fukuda M

2013-03-01

Full Text Available Masamichi Fukuda, Shinsuke Shibata, Naoko Shibata, Kenta Hagihara, Hiromoto Yaguchi, Hiromi Osada, Nobuo Takahashi, Eri Kubo, Hiroshi SasakiDepartment of Ophthalmology, Kanazawa Medical University, Uchinada, JapanPurpose: To investigate the safety of five types of antiglaucoma prostaglandin analog ophthalmic formulations, and to clarify their differences in accordance with contained additives (preservatives and surface-active agents.Methods: The following five types of ophthalmic solutions and three types of additives were investigated: latanoprost (Xalatan®; latanoprost, tafluprost (Tapros®; tafluprost, bimatoprost (Lumigan®; bimatoprost, travoprost (Travatan®; travoprost, travoprost (Travatan Z®; travoprost-Z, benzalkonium chloride (BAK, polyoxyethylene hardening castor oil 40 (HCO-40, and polysorbate 80 (P-80. These experimental solutions were exposed to the cultured cells of a rabbit-derived corneal cell line for a certain time, and the exposure time causing 50% cell damage (CD50, indicated by the ratio of viable cells to total cells was calculated (in vitro. In addition, corneal resistance (CR was measured and CR ratio (post-treatment CR/pretreatment CR × 100 was calculated (in vivo.Results: CD50 of each ophthalmic solution was the longest with tafluprost, followed by travoprost-Z, bimatoprost, travoprost, and latanoprost. CD50 of 0.005%, 0.01%, and 0.02% BAK was 14.5 minutes, 8.1 minutes, and 4.0 minutes, respectively. The number of viable cells decreased to 60%, 8 minutes after exposure with HCO-40, and 30 minutes after being exposed to P-80. The CR ratio was 81.0% with travoprost and 82.0% with latanoprost, indicating a significant posttreatment reduction of CR (P < 0.05. The CR ratio did not decrease after treatment with tafluprost, travoprost-Z, or bimatoprost. The CR ratio of 0.005%, 0.01%, and 0.02% BAK was 105.0%, 90.5%, and 68.7%, respectively, and that of HCO-40 and P-80 was 108.7% and 114.2%, respectively.Conclusion: BAK

An fMRI investigation of cognitive stages in reasoning by analogy.

Science.gov (United States)

Krawczyk, Daniel C; McClelland, M Michelle; Donovan, Colin M; Tillman, Gail D; Maguire, Mandy J

2010-06-25

We compared reasoning about four-term analogy problems in the format (A:B::C: D) to semantic and perceptual control conditions that required matching without analogical mapping. We investigated distinct phases of the problem solving process divided into encoding, mapping/inference, and response. Using fMRI, we assessed the brain activation relevant to each of these phases with an emphasis on achieving a better understanding of analogical reasoning relative to these other matching conditions. We predicted that the analogical condition would involve the most cognitive effort in the encoding and mapping/inference phases, while the control conditions were expected to engage greater prefrontal cortex (PFC) activation at the response period. Results showed greater activation for the analogical condition relative to the control conditions at the encoding phase in several predominantly left lateralized and medial areas of the PFC. Similar results were observed for the mapping/inference phase, though this difference was limited to the left PFC and rostral PFC. The response phase resulted in the fastest and most accurate responses in the analogy condition relative to the control conditions. This was accompanied by greater processing within the left lateral and the medial PFC for the control conditions relative to the analogy condition, consistent with most of the cognitive processing of the analogy condition having occurred in the prior task phases. Overall we demonstrate that the left ventral and dorsal lateral, medial, and rostral PFC are important in both the encoding of relational information, mapping and inference processes, and verification of semantic and perceptual responses in four term analogical reasoning. Copyright 2010 Elsevier B.V. All rights reserved.

Fecal bacterial communities of wild-captured and stranded green turtles (Chelonia mydas) on the Great Barrier Reef.

Science.gov (United States)

Ahasan, Md Shamim; Waltzek, Thomas B; Huerlimann, Roger; Ariel, Ellen

2017-12-01

Green turtles (Chelonia mydas) are endangered marine herbivores that break down food particles, primarily sea grasses, through microbial fermentation. However, the microbial community and its role in health and disease is still largely unexplored. In this study, we investigated and compared the fecal bacterial communities of eight wild-captured green turtles to four stranded turtles in the central Great Barrier Reef regions that include Bowen and Townsville. We used high-throughput sequencing analysis targeting the hypervariable V1-V3 regions of the bacterial 16S rRNA gene. At the phylum level, Firmicutes predominated among wild-captured green turtles, followed by Bacteroidetes and Proteobacteria. In contrast, Proteobacteria (Gammaproteobacteria) was the most significantly dominant phylum among all stranded turtles, followed by Bacteroidetes and Firmicutes. In addition, Fusobacteria was also significantly abundant in stranded turtles. No significant differences were found between the wild-captured turtles in Bowen and Townsville. At the family level, the core bacterial community consisted of 25 families that were identified in both the wild-captured and stranded green turtles, while two unique sets of 14 families each were only found in stranded or wild-captured turtles. The predominance of Bacteroides in all groups indicates the importance of these bacteria in turtle gut health. In terms of bacterial diversity and richness, wild-captured green turtles showed a higher bacterial diversity and richness compared with stranded turtles. The marked differences in the bacterial communities between wild-captured and stranded turtles suggest the possible dysbiosis in stranded turtles in addition to potential causal agents. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Analog and digital dividers for mass spectrometers

International Nuclear Information System (INIS)

Osipov, A.K.

1980-01-01

Errors of four different types of stress dividers used in statical mass-spectrometers for determination of mass number by accelerating stress are analyzed. The simplest flowsheet of the analog divider comprises operation amplifier, in the chain of the negative feedback of which a multiplication device on differential cascade is switched- in. This analog divider has high sensitivity to temperature and high error approximately 5%. Application of the multiplier on differential cascade with normalization permits to increase temperature stability and decrease the error up to 1%. Another type of the analog divider is a logarithmic divider the error of which is constant within the whole operation range and it constitutes 1-5%. The digital divider with a digital-analog transformer (DAT) has the error of +-0.015% which is determined by the error of detectors and resistance of keys in the locked state. Considered is the design of a divider based on transformation of the inlet stress into the time period. The error of the divider is determined in this case mainly by stress of the zero shift of the operation amplifier (it should be compensated) and relative threshold stability of the comparator triggering which equals (2-3)x10 -4 . It is noted that the divider with DAT application and the divider with the use of stress transformation within the time period are most perspective ones for statical mass-spectrometers [ru

The neural substrate of analogical reasoning: an fMRI study.

Science.gov (United States)

Luo, Qian; Perry, Conrad; Peng, Danling; Jin, Zhen; Xu, Duo; Ding, Guosheng; Xu, Shiyong

2003-10-01

This study investigated the anatomical substrate of analogical reasoning using functional magnetic resonance imaging. In the study, subjects performed a verbal analogy task (e.g., soldier is to army as drummer is to band) and, to control for activation caused by purely semantic access, a semantic judgment task. Significant activation differences between the verbal analogy and the semantic judgment task were found bilaterally in the prefrontal cortex (right BA 11/BA 47 and left BA45), the fusiform gyrus, and the basal ganglia; left lateralized in the postero-superior temporal gyrus (BA 22) and the (para) hippocampal region; and right lateralized in the anterior cingulate. The role of these areas in analogical reasoning is discussed.

Resource capture by single leaves

Energy Technology Data Exchange (ETDEWEB)

Long, S.P.

1992-05-01

Leaves show a variety of strategies for maximizing CO{sub 2} and light capture. These are more meaningfully explained if they are considered in the context of maximizing capture relative to the utilization of water, nutrients and carbohydrates reserves. There is considerable variation between crops in their efficiency of CO{sub 2} and light capture at the leaf level. Understanding of these mechanisms indicate some ways in which efficiency of resource capture could be level cannot be meaningfully considered without simultaneous understanding of implications at the canopy level. 36 refs., 5 figs., 1 tab.

Radiolabelled D2 agonists as prolactinoma imaging agents: Progress report for period February 1, 1988--January 31, 1989

International Nuclear Information System (INIS)

Otto, C.A.

1988-01-01

Targeted studies completed include the evaluation of tritiated N-0437, evaluation of 35 S-cysteamine, evaluation of 18 F-FDG and initiation of synthetic efforts towards the synthesis of iodinated N-0437 and pergolide analogs. The direction of the project has been changed due to several factors which include the decided lack of favorable experimental results, the excellence of results using muscarinic receptor ligands in pituitary, brain and heart and the contention of the DOE review panel that the original grant proposal was based on flawed assumptions together with their perceived lack of importance to pituitary imaging. In the final year of this grant, three studies will be completed. The first study is the continuation of synthetic efforts to prepare iodinated N-0437 and pergolide analogs for possible use as brain imaging agents. The second study is directed towards completion of biochemical evaluation of various muscarinic receptor analogs for heart, brain and (possible) pituitary imaging. The third study is to probe the use of quaternized D 2 receptor ligands for imaging peripheral dopaminergic receptors (including the pituitary). 14 refs., 1 fig., 7 tabs

SEAS: A simulated evolution approach for analog circuit synthesis

NARCIS (Netherlands)

Ning, Zhen-Qiu; Ning, Zhen-Qiu; Mouthaan, A.J.; Wallinga, Hans

1991-01-01

The authors present a simulated evolution approach for analog circuit synthesis based on an analogy with the natural selection process in biological environments and on the iterative improvements in solving engineering problems. A prototype framework based on this idea, called SEAS, has been

The effect of network topologies on the spreading of technological developments

International Nuclear Information System (INIS)

Kocsis, Gergely; Kun, Ferenc

2008-01-01

We study an agent-based model, as a special type of opinion dynamics, of the spreading of innovations in socio-economic systems varying the topology of agents' social contacts. The agents are organized on a square lattice where the connections are rewired with a certain probability. We show that the degree polydispersity and long range connections of agents can facilitate, but can also hinder the spreading of new technologies, depending on the amount of advantages provided by the innovation. We determine the critical fraction of innovative agents required to initiate spreading and to obtain a significant technological progress. As the fraction of innovative agents approaches the critical value, the spreading process slows down analogously to the critical slowing down observed at continuous phase transitions. The characteristic timescale at the critical point proved to have the same scaling as the average shortest path of the underlying social network. The model captures some relevant features of the spreading of innovations in telecommunication technologies

21 CFR 582.5477 - Methionine hydroxy analog and its calcium salts.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Methionine hydroxy analog and its calcium salts... Nutrients and/or Dietary Supplements 1 § 582.5477 Methionine hydroxy analog and its calcium salts. (a) Product. Methionine hydroxy analog and its calcium salts. (b) [Reserved] (c) Limitations, restrictions, or...

Chimpanzee (Pan troglodytes) relational matching: playing by their own (analogical) rules.

Science.gov (United States)

Flemming, Timothy M; Kennedy, Erica Hoy

2011-05-01

Chimpanzees (Pan troglodytes) have been known to exhibit rudimentary abilities in analogical reasoning (Flemming, Beran, Thompson, Kleider, & Washburn, 2008; Gillian, Premack, & Woodruff, 1981; Haun & Call, 2009; Thompson & Oden, 2000; Thompson, Oden, & Boysen, 1997). With a wide array of individual differences, little can be concluded about the species' capacity for analogies, much less their strategies employed for solving such problems. In this study, we examined analogical strategies in 3 chimpanzees using a 3-dimensional search task (e.g., Kennedy & Fragaszy, 2008). Food items were hidden under 1 of 2 or 3 plastic cups of varying sizes. Subsequently, chimpanzees searched for food under the cup of the same relative size in their own set of cups--reasoning by analogy. Two chimpanzees initially appeared to fail the first relational phase of the task. Meta-analyses revealed, however, that they were instead using a secondary strategy not rewarded by the contingencies of the task--choosing on the basis of the same relative position in the sample. Although this was not the intended strategy of the task, it was nonetheless analogical. In subsequent phases of the task, chimpanzees eventually learned to shift their analogical reasoning strategy to match the reward contingencies of the task and successfully choose on the basis of relative size. This evidence not only provides support for the analogical ape hypothesis (Thompson & Oden, 2000), but also exemplifies how foundational conceptually mediated analogical behavior may be for the chimpanzee. 2011 APA, all rights reserved

Analog and digital signal analysis from basics to applications

CERN Document Server

Cohen Tenoudji, Frédéric

2016-01-01

This book provides comprehensive, graduate-level treatment of analog and digital signal analysis suitable for course use and self-guided learning. This expert text guides the reader from the basics of signal theory through a range of application tools for use in acoustic analysis, geophysics, and data compression. Each concept is introduced and explained step by step, and the necessary mathematical formulae are integrated in an accessible and intuitive way. The first part of the book explores how analog systems and signals form the basics of signal analysis. This section covers Fourier series and integral transforms of analog signals, Laplace and Hilbert transforms, the main analog filter classes, and signal modulations. Part II covers digital signals, demonstrating their key advantages. It presents z and Fourier transforms, digital filtering, inverse filters, deconvolution, and parametric modeling for deterministic signals. Wavelet decomposition and reconstruction of non-stationary signals are also discussed...

22nd Workshop on Advances in Analog Circuit Design

CERN Document Server

Makinwa, Kofi; Harpe, Pieter

2014-01-01

This book is based on the 18 tutorials presented during the 22nd workshop on Advances in Analog Circuit Design.  Expert designers present readers with information about a variety of topics at the frontier of analog circuit design, including frequency reference, power management for systems-on-chip, and smart wireless interfaces.  This book serves as a valuable reference to the state-of-the-art, for anyone involved in analog circuit research and development.    ·         Provides a state-of-the-art reference in analog circuit design, written by experts from industry and academia; ·         Presents material in a tutorial-based format; ·         Includes coverage of frequency reference, power management for systems-on-chip, and smart wireless interfaces.

Analogy in systems management: a theoretical inquiry

Energy Technology Data Exchange (ETDEWEB)

Silverman, B.G.

1983-11-01

This theoretical analysis of the intuitive and diffuse characteristics of analogical reasoning processes is the first step in a research effort intended to lead to: understanding of common (and possibly costly) errors, pitfalls, travails, and problem-solving impediments; possible recommendations for improvements to organizational structures, control and coordination processes, and management information flows, and guidelines for a generalized analogical reasoning support framework (e.g., a handbook, a knowledge bank design, and/or even a software package/artificial intelligence program). 233 references.

Design of analog integrated circuits and systems

CERN Document Server

Laker, Kenneth R

1994-01-01

This text is designed for senior or graduate level courses in analog integrated circuits or design of analog integrated circuits. This book combines consideration of CMOS and bipolar circuits into a unified treatment. Also included are CMOS-bipolar circuits made possible by BiCMOS technology. The text progresses from MOS and bipolar device modelling to simple one and two transistor building block circuits. The final two chapters present a unified coverage of sample-data and continuous-time signal processing systems.

In vivo characterization of a smart MRI agent that displays an inverse response to calcium concentration.

Science.gov (United States)

Mamedov, Ilgar; Canals, Santiago; Henig, Jörg; Beyerlein, Michael; Murayama, Yusuke; Mayer, Hermann A; Logothetis, Nikos K; Angelovski, Goran

2010-12-15

Contrast agents for magnetic resonance imaging (MRI) that exhibit sensitivity toward specific ions or molecules represent a challenging but attractive direction of research. Here a Gd(3+) complex linked to an aminobis(methylenephosphonate) group for chelating Ca(2+) was synthesized and investigated. The longitudinal relaxivity (r(1)) of this complex decreases during the relaxometric titration with Ca(2+) from 5.76 to 3.57 mM(-1) s(-1) upon saturation. The r(1) is modulated by changes in the hydration number, which was confirmed by determination of the luminescence emission lifetimes of the analogous Eu(3+) complex. The initial in vivo characterization of this responsive contrast agent was performed by means of electrophysiology and MRI experiments. The investigated complex is fully biocompatible, having no observable effect on neuronal function after administration into the brain ventricles or parenchyma. Distribution studies demonstrated that the diffusivity of this agent is significantly lower compared with that of gadolinium-diethylenetriaminepentaacetic acid (Gd-DTPA).

Measurement of keV-neutron capture cross sections and capture gamma-ray spectra of Er isotopes