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Sample records for adder vipera berus

  1. Cold hardiness in the boreal adder, Vipera berus.

    PubMed

    Andersson, S; Johansson, L

    2001-01-01

    In three freezing experiments we examined the freeze tolerance in newborn adders, Vipera berus, from East-central Sweden. After a two to three hours exposure to freezing, ten out of eleven fast frozen snakes survived and recovered completely after being exposed to -3.1 degrees C on average. In the other two experiments with fast and slow freezing followed by long exposures lasting for 22-30 hours, none of the snakes survived average exposures at -4.8 degrees C or -3.8 degrees C, respectively. The glucose content of blood from frozen snakes was significantly higher than in unfrozen ones. The increase was small and its contribution to freeze tolerance doubtful. Compared to other freeze tolerant reptiles, the adder was categorised as virtually non freeze tolerant capable of surviving only a short exposure not colder than approximately -4 degrees C. Supercooling could play a role in winter survival but their precise choice of hibernation site is probably the most important.

  2. Incidence, pathology, and treatment of adder (Vipera berus L.) bites in man.

    PubMed Central

    Reading, C J

    1996-01-01

    A review of published reports on the incidence, pathology, and treatment of adder (Vipera berus) bites in man in the United Kingdom and Europe produced numerous case studies but little information about the impact od adders as a threat to public health. Adder bites in man are not uncommon (at least 44/year and probably more than 90/year in the United Kingdom) and, although they have been recorded for every month of the year between February and October, envenoming is most likely to occur during June, July, and August. Most adder bites are on the hand (51.6%) or foot (38.2%). The effects of adder bite envenoming are now know. Effective treatment protocols can reduce both the length of time victims spend in hospital and the morbidity in the affected areas: they have resulted in a decline in the death rate over the last 30 years, so that deaths are now rare. PMID:8894864

  3. The adder (Vipera berus) in Southern Altay Mountains: population characteristics, distribution, morphology and phylogenetic position.

    PubMed

    Cui, Shaopeng; Luo, Xiao; Chen, Daiqiang; Sun, Jizhou; Chu, Hongjun; Li, Chunwang; Jiang, Zhigang

    2016-01-01

    As the most widely distributed snake in Eurasia, the adder (Vipera berus) has been extensively investigated in Europe but poorly understood in Asia. The Southern Altay Mountains represent the adder's southern distribution limit in Central Asia, whereas its population status has never been assessed. We conducted, for the first time, field surveys for the adder at two areas of Southern Altay Mountains using a combination of line transects and random searches. We also described the morphological characteristics of the collected specimens and conducted analyses of external morphology and molecular phylogeny. The results showed that the adder distributed in both survey sites and we recorded a total of 34 sightings. In Kanas river valley, the estimated encounter rate over a total of 137 km transects was 0.15 ± 0.05 sightings/km. The occurrence of melanism was only 17%. The small size was typical for the adders in Southern Altay Mountains in contrast to other geographic populations of the nominate subspecies. A phylogenetic tree obtained by Bayesian Inference based on DNA sequences of the mitochondrial cytochrome b (1,023 bp) grouped them within the Northern clade of the species but failed to separate them from the subspecies V. b. sachalinensis. Our discovery extends the distribution range of V. berus and provides a basis for further researches. We discuss the hypothesis that the adder expands its distribution border to the southwest along the mountains' elevation gradient, but the population abundance declines gradually due to a drying climate.

  4. The adder (Vipera berus) in Southern Altay Mountains: population characteristics, distribution, morphology and phylogenetic position.

    PubMed

    Cui, Shaopeng; Luo, Xiao; Chen, Daiqiang; Sun, Jizhou; Chu, Hongjun; Li, Chunwang; Jiang, Zhigang

    2016-01-01

    As the most widely distributed snake in Eurasia, the adder (Vipera berus) has been extensively investigated in Europe but poorly understood in Asia. The Southern Altay Mountains represent the adder's southern distribution limit in Central Asia, whereas its population status has never been assessed. We conducted, for the first time, field surveys for the adder at two areas of Southern Altay Mountains using a combination of line transects and random searches. We also described the morphological characteristics of the collected specimens and conducted analyses of external morphology and molecular phylogeny. The results showed that the adder distributed in both survey sites and we recorded a total of 34 sightings. In Kanas river valley, the estimated encounter rate over a total of 137 km transects was 0.15 ± 0.05 sightings/km. The occurrence of melanism was only 17%. The small size was typical for the adders in Southern Altay Mountains in contrast to other geographic populations of the nominate subspecies. A phylogenetic tree obtained by Bayesian Inference based on DNA sequences of the mitochondrial cytochrome b (1,023 bp) grouped them within the Northern clade of the species but failed to separate them from the subspecies V. b. sachalinensis. Our discovery extends the distribution range of V. berus and provides a basis for further researches. We discuss the hypothesis that the adder expands its distribution border to the southwest along the mountains' elevation gradient, but the population abundance declines gradually due to a drying climate. PMID:27602300

  5. The adder (Vipera berus) in Southern Altay Mountains: population characteristics, distribution, morphology and phylogenetic position

    PubMed Central

    Cui, Shaopeng; Luo, Xiao; Chen, Daiqiang; Sun, Jizhou; Chu, Hongjun

    2016-01-01

    As the most widely distributed snake in Eurasia, the adder (Vipera berus) has been extensively investigated in Europe but poorly understood in Asia. The Southern Altay Mountains represent the adder’s southern distribution limit in Central Asia, whereas its population status has never been assessed. We conducted, for the first time, field surveys for the adder at two areas of Southern Altay Mountains using a combination of line transects and random searches. We also described the morphological characteristics of the collected specimens and conducted analyses of external morphology and molecular phylogeny. The results showed that the adder distributed in both survey sites and we recorded a total of 34 sightings. In Kanas river valley, the estimated encounter rate over a total of 137 km transects was 0.15 ± 0.05 sightings/km. The occurrence of melanism was only 17%. The small size was typical for the adders in Southern Altay Mountains in contrast to other geographic populations of the nominate subspecies. A phylogenetic tree obtained by Bayesian Inference based on DNA sequences of the mitochondrial cytochrome b (1,023 bp) grouped them within the Northern clade of the species but failed to separate them from the subspecies V. b. sachalinensis. Our discovery extends the distribution range of V. berus and provides a basis for further researches. We discuss the hypothesis that the adder expands its distribution border to the southwest along the mountains’ elevation gradient, but the population abundance declines gradually due to a drying climate. PMID:27602300

  6. The adder (Vipera berus) in Southern Altay Mountains: population characteristics, distribution, morphology and phylogenetic position

    PubMed Central

    Cui, Shaopeng; Luo, Xiao; Chen, Daiqiang; Sun, Jizhou; Chu, Hongjun

    2016-01-01

    As the most widely distributed snake in Eurasia, the adder (Vipera berus) has been extensively investigated in Europe but poorly understood in Asia. The Southern Altay Mountains represent the adder’s southern distribution limit in Central Asia, whereas its population status has never been assessed. We conducted, for the first time, field surveys for the adder at two areas of Southern Altay Mountains using a combination of line transects and random searches. We also described the morphological characteristics of the collected specimens and conducted analyses of external morphology and molecular phylogeny. The results showed that the adder distributed in both survey sites and we recorded a total of 34 sightings. In Kanas river valley, the estimated encounter rate over a total of 137 km transects was 0.15 ± 0.05 sightings/km. The occurrence of melanism was only 17%. The small size was typical for the adders in Southern Altay Mountains in contrast to other geographic populations of the nominate subspecies. A phylogenetic tree obtained by Bayesian Inference based on DNA sequences of the mitochondrial cytochrome b (1,023 bp) grouped them within the Northern clade of the species but failed to separate them from the subspecies V. b. sachalinensis. Our discovery extends the distribution range of V. berus and provides a basis for further researches. We discuss the hypothesis that the adder expands its distribution border to the southwest along the mountains’ elevation gradient, but the population abundance declines gradually due to a drying climate.

  7. Cloacal aerobic bacterial flora and absence of viruses in free-living slow worms (Anguis fragilis), grass snakes (Natrix natrix) and European Adders (Vipera berus) from Germany.

    PubMed

    Schmidt, Volker; Mock, Ronja; Burgkhardt, Eileen; Junghanns, Anja; Ortlieb, Falk; Szabo, Istvan; Marschang, Rachel; Blindow, Irmgard; Krautwald-Junghanns, Maria-Elisabeth

    2014-12-01

    Disease problems caused by viral or bacterial pathogens are common in reptiles kept in captivity. There is no information available on the incidence of viral pathogens or the physiological cloacal bacterial flora of common free-living reptiles in Germany. Therefore, 56 free-living reptiles including 23 European adders (Vipera berus), 12 grass snakes (Natrix natrix) and 21 slow worms (Anguis fragilis) were investigated on the island Hiddensee in northeastern Germany. Pharyngeal and cloacal swabs were taken immediately after capture. Bacteriological examination was performed from the cloacal swabs to study the aerobic cloacal flora. Molecular biological examination included amplification of DNA or RNA from adeno-, rana- and ferlaviruses as well as culturing on Russell's viper heart cells for virus isolation. Salmonella spp. were isolated from European adders but not from the other reptiles examined. The minimal inhibitory concentration was determined from the isolated Salmonella spp. However, some potentially human pathogenic bacteria, such as Proteus vulgaris, Aeromonas hydrophila, Klebsiella pneumoniae and Escherichia coli were isolated. Viruses were not detected in any of the examined reptiles. To the authors' best knowledge, the present study is the first survey of viral pathogens in free-living snakes and slow worms in Germany and the first survey of cloacal aerobic bacterial flora of slow worms.

  8. Bile acids of snakes of the subfamily Viperinae and the biosynthesis of C-23-hydroxylated bile acids in liver homogenate fractions from the adder, Vipera berus (Linn.).

    PubMed Central

    Ikawa, S; Tammar, A R

    1976-01-01

    1. Analysis of bile salts of four snakes of the subfamily Viperinae showed that their bile acids consisted mainly of C-23-hydroxylated bile acids. 2. Incubations of 14C-labelled sodium cholate (3 alpha, 7 alpha, 12 alpha-trihydroxy-5 beta-cholan-24-oate) and deoxycholate (3 alpha, 12 alpha-dihydroxy-5 beta-cholan-24-oate) with whole and fractionated adder liver homogenates were carried out in the presence of molecular oxygen and NADPH or an NADPH-generating system. The formation of C-23-hydroxylated bile acids, namely bitocholic acid (3 alpha, 12 alpha, 23xi-trihydroxy-5 beta-cholan-24-oic acid) and 3 alpha, 7 alpha, 12 alpha, 23 xi-tetrahydroxy-cholanic acid (3 alpha, 7 alpha, 12 alpha, 23 xi-tetrahydroxy-5 beta-cholan-24-oic acid), was observed mainly in the microsomal fraction and partly in the mitochondrial fraction. 3. Biosynthetic pathways of C-23-hydroxylated bile acids are discussed. PMID:6007

  9. Immunological Cross-Reactivity and Neutralisation of European Viper Venoms with the Monospecific Vipera berus Antivenom ViperaTAb

    PubMed Central

    Casewell, Nicholas R.; Al-Abdulla, Ibrahim; Smith, David; Coxon, Ruth; Landon, John

    2014-01-01

    Medically important cases of snakebite in Europe are predominately caused by European vipers of the genus Vipera. The mainstay of snakebite therapy is polyclonal antibody therapy, referred to as antivenom. Here we investigate the capability of the monospecific V. berus antivenom, ViperaTAb®, to cross-react with, and neutralise lethality induced by, a variety of European vipers. Using ELISA and immunoblotting, we find that ViperaTAb® antibodies recognise and bind to the majority of toxic components found in the venoms of the Vipera species tested at comparably high levels to those observed with V. berus. Using in vivo pre-clinical efficacy studies, we demonstrate that ViperaTAb® effectively neutralises lethality induced by V. berus, V. aspis, V. ammodytes and V. latastei venoms and at much higher levels than those outlined by regulatory pharmacopoeial guidelines. Notably, venom neutralisation was found to be superior to (V. berus, V. aspis and V. latastei), or as equally effective as (V. ammodytes), the monospecific V. ammodytes “Zagreb antivenom”, which has long been successfully used for treating European snake envenomings. This study suggests that ViperaTAb® may be a valuable therapeutic product for treating snakebite by a variety of European vipers found throughout the continent. PMID:25153254

  10. Myocardial cell damage in 24 dogs bitten by the common European viper (Vipera berus).

    PubMed

    Pelander, L; Ljungvall, I; Häggström, J

    2010-05-29

    This study investigated whether myocardial damage, as reflected by increased serum concentrations of cardiac-specific troponin I (cTnI), develops in dogs as a result of a bite from a common European viper (Vipera berus), and whether this damage occurs in the absence of clinically relevant ECG abnormalities. Twenty-four dogs presented following a snake bite were tested. On admission, and after 12, 24 and 36 hours, an ECG was recorded and serum was collected for analysis of cTnI from all the dogs. Thirteen dogs (54 per cent) had an undetectable serum cTnI concentration (<0.2 microg/l) and no abnormalities on ECG, five dogs (21 per cent) had increased serum concentrations of cTnI and no ECG abnormalities, six dogs (12.5 per cent) had increased cTnI concentrations and ECG abnormalities, and six dogs (12.5 per cent) had ECG abnormalities and undetectable cTnI concentrations. Only three dogs (12.5 per cent) had serum cTnI concentrations exceeding 1.0 microg/l at any time during the study. Evidence of myocardial cell damage was found in eight (32 per cent) of the 24 dogs. Cardiac arrhythmia was detected in three of these eight dogs. PMID:20511652

  11. Lethal case of Vipera bersus bite.

    PubMed

    Tranca, Sebastian; Cocis, Mihaela; Antal, Oana

    2016-01-01

    Adder bites are rare events, but they can be fatal. Three adder types live in Romania - Vipera ammodytes, Vipera ursini and Vipera berus. Most adder bites happen during the summer with a peak incidence between July and August. Here we present the case of a 56 years old male patient who was bitten by an adder. The clinical presentation was severe from the beginning with a GCS of 3 points, respiratory and cardiovascular failure; despite of adequate treatment the patient developed multiorgan dysfunction and died 36 hours after the ICU admission. The aim of this report is to raise awareness that snake bites can have a life-threatening course and need immediate attention and medical care. PMID:27547066

  12. Lethal case of Vipera bersus bite

    PubMed Central

    TRANCA, SEBASTIAN; COCIS, MIHAELA; ANTAL, OANA

    2016-01-01

    Adder bites are rare events, but they can be fatal. Three adder types live in Romania - Vipera ammodytes, Vipera ursini and Vipera berus. Most adder bites happen during the summer with a peak incidence between July and August. Here we present the case of a 56 years old male patient who was bitten by an adder. The clinical presentation was severe from the beginning with a GCS of 3 points, respiratory and cardiovascular failure; despite of adequate treatment the patient developed multiorgan dysfunction and died 36 hours after the ICU admission. The aim of this report is to raise awareness that snake bites can have a life-threatening course and need immediate attention and medical care. PMID:27547066

  13. Neutralization of Vipera and Macrovipera venoms by two experimental polyvalent antisera: a study of paraspecificity.

    PubMed

    Archundia, Irving G; de Roodt, Adolfo R; Ramos-Cerrillo, Blanca; Chippaux, Jean-Philippe; Olguín-Pérez, Laura; Alagón, Alejandro; Stock, Roberto P

    2011-06-01

    We conducted an extensive study of neutralization of lethality of 11 species and one subspecies of snakes of the genus Vipera, and of five species of Macrovipera, by two experimental equine antisera. One antiserum was a trivalent preparation raised against the venoms of Vipera aspis aspis, Vipera berus berus and Vipera ammodytes ammodytes; the other was a pentavalent preparation that also included venoms of Vipera (now Montivipera) xanthina and Macrovipera lebetina obtusa. We measured specific neutralization of lethality against all venoms included in the immunization schemes, and paraspecific neutralization against the venoms of Vipera ammodytes montandoni, Vipera (Montivipera) bornmuelleri, Vipera latastei, Vipera (Mo.) latifii, Vipera (Mo.) lotievi, Vipera (Daboia) palaestinae, Vipera (Mo.) raddei and Vipera seoanei, as well as against Macrovipera (D.) deserti, Macrovipera lebetina cernovi, Macrovipera lebetina turanica and Macrovipera schweitzeri. We found an important degree of paraspecific protection within each genera (omitting recent reclassification) that was quite independent of both the lethal potency of the venoms and their geographic origin. This information may be of use to clinicians charged with the treatment of Vipera or Macrovipera envenomations with non-specific antivenoms.

  14. ADDER CIRCUIT

    DOEpatents

    Jacobsohn, D.H.; Merrill, L.C.

    1959-01-20

    An improved parallel addition unit is described which is especially adapted for use in electronic digital computers and characterized by propagation of the carry signal through each of a plurality of denominationally ordered stages within a minimum time interval. In its broadest aspects, the invention incorporates a fast multistage parallel digital adder including a plurality of adder circuits, carry-propagation circuit means in all but the most significant digit stage, means for conditioning each carry-propagation circuit during the time period in which information is placed into the adder circuits, and means coupling carry-generation portions of thc adder circuit to the carry propagating means.

  15. A Single Dose of ViperfavTM May Be Inadequate for Vipera ammodytes Snake Bite: A Case Report and Pharmacokinetic Evaluation

    PubMed Central

    Kurtović, Tihana; Brvar, Miran; Grenc, Damjan; Lang Balija, Maja; Križaj, Igor; Halassy, Beata

    2016-01-01

    ViperfavTM is a commercial F(ab’)2 antivenom prepared against European vipers venom. It is safe and effective for treating envenomation caused by Vipera aspis and Vipera berus. Therapeutic efficacy for treating Vipera ammodytes ammodytes (V. a. ammodytes) envenoming has not been yet described, although protective efficacy has been demonstrated in preclinical studies. We report on a 32-year-old man bitten by V. a. ammodytes who was treated with Viperfav™. Viperfav™ promptly reduced local extension and improved systemic pathological signs, but 24 h after the incident a recurrence of thrombocytopenia occurred despite a favorable pharmacokinetic profile with systemic clearance (1.64 (mL·h−1)·kg−1) and elimination half-life (97 h) among the highest ever reported. The recommended dose of Viperfav™ for V. aspis and V. berus bites may be inadequate for serious V. a. ammodytes envenomations. Following V. a. ammodytes bite, serial blood counts and coagulation profiles should be performed to help guide Viperfav™ treatment, along with supplemental administration as indicated. PMID:27548220

  16. A Single Dose of Viperfav(TM) May Be Inadequate for Vipera ammodytes Snake Bite: A Case Report and Pharmacokinetic Evaluation.

    PubMed

    Kurtović, Tihana; Brvar, Miran; Grenc, Damjan; Lang Balija, Maja; Križaj, Igor; Halassy, Beata

    2016-01-01

    Viperfav(TM) is a commercial F(ab')₂ antivenom prepared against European vipers venom. It is safe and effective for treating envenomation caused by Vipera aspis and Vipera berus. Therapeutic efficacy for treating Vipera ammodytes ammodytes (V. a. ammodytes) envenoming has not been yet described, although protective efficacy has been demonstrated in preclinical studies. We report on a 32-year-old man bitten by V. a. ammodytes who was treated with Viperfav™. Viperfav™ promptly reduced local extension and improved systemic pathological signs, but 24 h after the incident a recurrence of thrombocytopenia occurred despite a favorable pharmacokinetic profile with systemic clearance (1.64 (mL·h(-1))·kg(-1)) and elimination half-life (97 h) among the highest ever reported. The recommended dose of Viperfav™ for V. aspis and V. berus bites may be inadequate for serious V. a. ammodytes envenomations. Following V. a. ammodytes bite, serial blood counts and coagulation profiles should be performed to help guide Viperfav™ treatment, along with supplemental administration as indicated. PMID:27548220

  17. On fast carry select adders

    NASA Technical Reports Server (NTRS)

    Shamanna, M.; Whitaker, S.

    1992-01-01

    This paper presents an architecture for a high-speed carry select adder with very long bit lengths utilizing a conflict-free bypass scheme. The proposed scheme has almost half the number of transistors and is faster than a conventional carry select adder. A comparative study is also made between the proposed adder and a Manchester carry chain adder which shows that the proposed scheme has the same transistor count, without suffering any performance degradation, compared to the Manchester carry chain adder.

  18. Inductive Adder development

    SciTech Connect

    Miller, R.B.; Davis, B.B.; Bayless, J.

    1989-05-01

    TITAN has successfully developed an Inductive Adder for use with a Hewlett-Packard Model 43734A Marx pulser. The unit provides an 800 kV peak output pulse to a modified HP 5081-9551 1 MV x-ray tube. The tube fits into the adder unit, and can thus be remotely operated. It delivers a peak on-axis dose of 35 mR at a one meter distance. Supporting radiography analyses, a description of the inductive adder approach and construction, and detailed test data are presented.

  19. The Forbidden Quantum Adder

    NASA Astrophysics Data System (ADS)

    Alvarez-Rodriguez, U.; Sanz, M.; Lamata, L.; Solano, E.

    2015-07-01

    Quantum information provides fundamentally different computational resources than classical information. We prove that there is no unitary protocol able to add unknown quantum states belonging to different Hilbert spaces. This is an inherent restriction of quantum physics that is related to the impossibility of copying an arbitrary quantum state, i.e., the no-cloning theorem. Moreover, we demonstrate that a quantum adder, in absence of an ancillary system, is also forbidden for a known orthonormal basis. This allows us to propose an approximate quantum adder that could be implemented in the lab. Finally, we discuss the distinct character of the forbidden quantum adder for quantum states and the allowed quantum adder for density matrices.

  20. Reappraisal of Vipera aspis Venom Neurotoxicity

    PubMed Central

    Ferquel, Elisabeth; de Haro, Luc; Jan, Virginie; Guillemin, Isabelle; Jourdain, Sabine; Teynié, Alexandre; d'Alayer, Jacques; Choumet, Valérie

    2007-01-01

    Background The variation of venom composition with geography is an important aspect of intraspecific variability in the Vipera genus, although causes of this variability remain unclear. The diversity of snake venom is important both for our understanding of venomous snake evolution and for the preparation of relevant antivenoms to treat envenomations. A geographic intraspecific variation in snake venom composition was recently reported for Vipera aspis aspis venom in France. Since 1992, cases of human envenomation after Vipera aspis aspis bites in south-east France involving unexpected neurological signs were regularly reported. The presence of genes encoding PLA2 neurotoxins in the Vaa snake genome led us to investigate any neurological symptom associated with snake bites in other regions of France and in neighboring countries. In parallel, we used several approaches to characterize the venom PLA2 composition of the snakes captured in the same areas. Methodology/Principal Findings We conducted an epidemiological survey of snake bites in various regions of France. In parallel, we carried out the analysis of the genes and the transcripts encoding venom PLA2s. We used SELDI technology to study the diversity of PLA2 in various venom samples. Neurological signs (mainly cranial nerve disturbances) were reported after snake bites in three regions of France: Languedoc-Roussillon, Midi-Pyrénées and Provence-Alpes-Côte d'Azur. Genomes of Vipera aspis snakes from south-east France were shown to contain ammodytoxin isoforms never described in the genome of Vipera aspis from other French regions. Surprisingly, transcripts encoding venom neurotoxic PLA2s were found in snakes of Massif Central region. Accordingly, SELDI analysis of PLA2 venom composition confirmed the existence of population of neurotoxic Vipera aspis snakes in the west part of the Massif Central mountains. Conclusions/Significance The association of epidemiological studies to genetic, biochemical and

  1. Quantum Adder of Classical Numbers

    NASA Astrophysics Data System (ADS)

    Cherkas, A. V.; Chivilikhin, S. A.

    2016-08-01

    In this article we show the precise algorithm of functioning of quantum adder on the example of addition of two 2-bit numbers. It consists of the quantum Fourier transformer and conditional rotation gates that let us use the minimum number of qubits to get the addition realization of the sum. Despite the fact that the algorithm uses the minimum amount of operations this accelerates the process of the adder.

  2. EUV mask particle adders during scanner exposure

    NASA Astrophysics Data System (ADS)

    Hyun, Yoonsuk; Kim, Jinsoo; Kim, Kyuyoung; Koo, Sunyoung; Kim, SeoMin; Kim, Youngsik; Lim, Changmoon; Kwak, Nohjung

    2015-03-01

    As EUV reaches high volume manufacturing, scanner source power and reticle defectivity attract a lot of attention. Keeping a EUV mask clean after mask production is as essential as producing a clean EUV mask. Even though EUV pellicle is actively investigated, we might expose EUV masks without EUV pellicle for some time. To keep clean EUV mask under pellicle-less lithography, EUV scanner cleanliness needs to meet the requirement of high volume manufacturing. In this paper, we will show the cleanliness of EUV scanners in view of mask particle adders during scanner exposure. From this we will find several tendencies of mask particle adders depending on mask environment in scanner. Further we can categorize mask particle adders, which could show the possible causes of particle adders during exposure in scanners.

  3. [Snake bite in a 53-year-old female tourist].

    PubMed

    Bertheau, S; Aghdassi, A; Otto, M; Hegenscheid, K; Runge, S; Lerch, M M; Simon, P

    2015-02-01

    Snake bites are rare events in Germany and are not life-threatening with usually only mild clinical symptoms. The most widespread venomous snake is the common European adder (Vipera berus). Here we present the case of a 53-year-old woman who was bitten by a common adder. Although the patient was initially in stable condition she developed edematous swelling of the complete lower limb, subcutaneous bleeding, and rhabdomyolysis. The aim of this report is to raise awareness that even in a central European country like Germany snake bites with a life-threatening course can occur and need immediate attention and medical care. PMID:25617003

  4. The LMF triaxial MITL voltage adder system

    SciTech Connect

    Mazarakis, M.G.; Smith, D.L.; Bennett, L.F.; Lockner, T.R.; Olson, R.E.; Poukey, J.W.

    1992-12-31

    The light-ion microfusion driver design consists of multiple accelerating modules fired in coincidence and sequentially in order to provide the desired ion energy, power pulse shape and energy deposition uniformity on an Inertial Confinement Fusion (ICF) target. The basic energy source is a number of Marx generators which, through the appropriate pulse power conditioning, provide the necessary voltage pulse wave form to the accelerating gaps or feeds of each module. The cavity gaps are inductively isolated, and the voltage addition occurs in the center conductor of the voltage adder which is the positive electrode while the electrons of the sheath flow closer to the outer cylinder which is the magnetically insulated cathode electrode. Each module powers a separate two-stage extraction diode which provides a low divergence ion beam. In order to provide the two separate voltage pulses required by the diode, a triaxial adder system is designed for each module. The voltage addition occurs in two separate MITLs. The center hollow cylinder (anode) of the second MITL also serves as the outer cathode electrode for the extension of the first voltage adder MITL. The voltage of the second stage is about twice that of the first stage. The cavities are connected in series to form the outer cylinder of each module. The accelerating modules are positioned radially in a symmetrical way around the fusion chamber. A preliminary conceptual design of the LMF modules with emphasis on the voltage adders and extension MITLs will be presented and discussed.

  5. Fast and area-efficient VLSI adders

    SciTech Connect

    Han, T.D.

    1987-01-01

    Area-time tradeoffs have been an important topic in VLSI research. This is because the cost of fabricating a circuit is an exponential function of its area. As a result, optimizing the area of a VLSI design is much more important than optimizing the speed of an algorithm. This dissertation examines area-time tradeoffs in VLSI for prefix computation using graph representations of the problem. Since the problem is intimately related to binary addition, results obtained lead to design of area-time efficient VLSI adders. This is a major goal of the work: to design very low latency-addition circuitry that is also area-efficient. To this end, a new graph representation is presented for prefix computation that leads to the design of a fast, area-efficient binary adder. The new graph is a combination of previously known graph representations for prefix computation, and its area is close to known lower bounds on the VLSI area of parallel prefix graphs. Using it, the author designed VLSI adders having area A = O(n log n) whose delay time is the lowest possible value, i.e., the fastest possible area-efficient VLSI adder. For the large number of inputs, the pipelined model of prefix circuit is presented. Also presented is a fault-tolerant model for the developed prefix circuit, based on the partitioning of the network.

  6. A comparison of two fast binary adder configurations

    NASA Technical Reports Server (NTRS)

    Canaris, J.; Cameron, K.

    1990-01-01

    Conditional sum and binary lookahead carry are two methods for performing fast binary addition. These methods are quite different, but the adders have a common feature that makes them interesting to compare. Both adders have the carry generating logic implemented as a binary tree, which grows in depth as log(sub 2) n,n equals the number of bits in the adder. The delay in the carry paths also grows in proportion to log(sub 2) n. This paper shows that the Transmission-Gate Conditional-Sum adder and the binary lookahead carry adder have the same speed of addition, but that the conditional sum adder requires only 46 percent of the area.

  7. A decimal carry-free adder

    NASA Astrophysics Data System (ADS)

    Nikmehr, Hooman; Phillips, Braden; Lim, Cheng-Chew

    2005-02-01

    Recently, decimal arithmetic has become attractive in the financial and commercial world including banking, tax calculation, currency conversion, insurance and accounting. Although computers are still carrying out decimal calculation using software libraries and binary floating-point numbers, it is likely that in the near future, all processors will be equipped with units performing decimal operations directly on decimal operands. One critical building block for some complex decimal operations is the decimal carry-free adder. This paper discusses the mathematical framework of the addition, introduces a new signed-digit format for representing decimal numbers and presents an efficient architectural implementation. Delay estimation analysis shows that the adder offers improved performance over earlier designs.

  8. Efficient radix-r adders for nanoelectronics

    NASA Astrophysics Data System (ADS)

    Moaiyeri, Mohammad Hossein; Chavoshisani, Reza; Jalali, Ali; Navi, Keivan; Hashemipour, Omid

    2016-02-01

    In this study, a new design method and efficient designs for radix-r adders are proposed for carbon nanotube field effect transistor (CNFET) FET nanotechnology. This application also investigates the capability of the nanoscale device for designing high-performance analogue circuits. The proposed designs benefit from the unique electrical properties of CNFET, such as near-ideal current voltage characteristics, very high transconductance, high-performance switches and very high-performance and high-gain binary inverters, at nanoscale. Moreover, adjustable threshold voltage and the same mobility of electrons and holes in a CNFET facilitate the design and modification procedures. The proposed design can be considered as an instance of a general adder, capable of adding radix-r digits with high precision. It is noteworthy that a very limited number of carbon nanotube diameters for designing the proposed adder are needed, which enhance the manufacturability. The proposed circuits are designed based on arithmetic relations and are also verified at 32 nm feature size using HSPICE and the Stanford standard SPICE model.

  9. A novel reversible carry-selected adder with low latency

    NASA Astrophysics Data System (ADS)

    Li, Ming-Cui; Zhou, Ri-Gui

    2016-07-01

    Reversible logic is getting more and more attention in quantum computing, optical computing, nanotechnology and low-power complementary metal oxide semiconductor designs since reversible circuits do not loose information during computation and have only small energy dissipation. In this paper, a novel carry-selected reversible adder is proposed primarily optimised for low latency. A 4-bit reversible full adder with two kinds of outputs, minimum delay and optimal quantum cost is presented as the building block for ?-bit reversible adder. Three new reversible gates NPG (new Peres gate), TEPG (triple extension of Peres gate) and RMUX21 (reversible 2-to-1 multiplexer) are proposed and utilised to design efficient adder units. The secondary carry propagation chain is carefully designed to reduce the time consumption. The novelty of the proposed design is the consideration of low latency. The comparative study shows that the proposed adder achieves the improvement from 61.46% to 95.29% in delay over the existing designs.

  10. Protein C activity in dogs envenomed by Vipera palaestinae.

    PubMed

    Hadar, Gil; Kelmer, Efrat; Segev, Gilad; Bruchim, Yaron; Aroch, Itamar

    2014-09-01

    Vipera palaestinae is responsible for most envenomations in humans and domestic animal in Israel. Its venom has pro- and anticoagulant properties. Protein C is a major natural anticoagulant, preventing excess clotting and thrombosis. This study investigated protein C activity and its prognostic value, as well as several other hemostatic analytes in dogs (Canis familiaris) accidently envenomed by V. palaestinae. Protein C activity was compared between envenomed dogs and 33 healthy control dogs. Mean protein C was lower in dogs envenomed by V. palaestinae compared to controls (12.9% vs. 22.9%, respectively; P < 0.01). It was positively correlated with antithrombin activity (r = 0.3, P = 0.04), but not with other hemostatic analytes. The overall mortality rate was 13%, and at presentation no significant protein C activity difference was noted between survivors and non-survivors. A receiver operator characteristics analysis of protein C activity as a predictor of mortality had an area under the curve of 0.7 (95% confidence interval 0.52-0.87). A protein C cutoff point of 8% corresponded to sensitivity and specificity of 70% and 57%, respectively. Dogs diagnosed with consumptive coagulopathy (14%) tended to have lower protein C activity compared to others; however, their mortality did differ from that of other dogs. This is the first study assessing protein C activity in V. palaestinae victims. Decreased protein C activity in such dogs may play a role in formation of thrombosis and hemostatic derangement as well as inflammation in V. palaestinae envenomations.

  11. Reproducible and controllable induction voltage adder for scaled beam experiments

    NASA Astrophysics Data System (ADS)

    Sakai, Yasuo; Nakajima, Mitsuo; Horioka, Kazuhiko

    2016-08-01

    A reproducible and controllable induction adder was developed using solid-state switching devices and Finemet cores for scaled beam compression experiments. A gate controlled MOSFET circuit was developed for the controllable voltage driver. The MOSFET circuit drove the induction adder at low magnetization levels of the cores which enabled us to form reproducible modulation voltages with jitter less than 0.3 ns. Preliminary beam compression experiments indicated that the induction adder can improve the reproducibility of modulation voltages and advance the beam physics experiments.

  12. High Speed Capacitor-Inverter Based Carbon Nanotube Full Adder

    PubMed Central

    2010-01-01

    Carbon Nanotube filed-effect transistor (CNFET) is one of the promising alternatives to the MOS transistors. The geometry-dependent threshold voltage is one of the CNFET characteristics, which is used in the proposed Full Adder cell. In this paper, we present a high speed Full Adder cell using CNFETs based on majority-not (Minority) function. Presented design uses eight transistors and eight capacitors. Simulation results show significant improvement in terms of delay and power-delay product in comparison to contemporary CNFET Adder Cells. Simulations were carried out using HSPICE based on CNFET model with 0.6 V VDD. PMID:20671796

  13. High speed capacitor-inverter based carbon nanotube full adder.

    PubMed

    Navi, K; Rashtian, M; Khatir, A; Keshavarzian, P; Hashemipour, O

    2010-01-01

    Carbon Nanotube filed-effect transistor (CNFET) is one of the promising alternatives to the MOS transistors. The geometry-dependent threshold voltage is one of the CNFET characteristics, which is used in the proposed Full Adder cell. In this paper, we present a high speed Full Adder cell using CNFETs based on majority-not (Minority) function. Presented design uses eight transistors and eight capacitors. Simulation results show significant improvement in terms of delay and power-delay product in comparison to contemporary CNFET Adder Cells. Simulations were carried out using HSPICE based on CNFET model with 0.6 V VDD. PMID:20671796

  14. Reproducible and controllable induction voltage adder for scaled beam experiments.

    PubMed

    Sakai, Yasuo; Nakajima, Mitsuo; Horioka, Kazuhiko

    2016-08-01

    A reproducible and controllable induction adder was developed using solid-state switching devices and Finemet cores for scaled beam compression experiments. A gate controlled MOSFET circuit was developed for the controllable voltage driver. The MOSFET circuit drove the induction adder at low magnetization levels of the cores which enabled us to form reproducible modulation voltages with jitter less than 0.3 ns. Preliminary beam compression experiments indicated that the induction adder can improve the reproducibility of modulation voltages and advance the beam physics experiments. PMID:27587112

  15. Half adder capabilities of a coupled quantum dot device.

    PubMed

    Pfeffer, P; Hartmann, F; Neri, I; Schade, A; Emmerling, M; Kamp, M; Gammaitoni, L; Höfling, S; Worschech, L

    2016-05-27

    In this paper we demonstrate two realizations of a half adder based on a voltage-rectifying mechanism involving two Coulomb-coupled quantum dots. First, we examine the ranges of operation of the half adder's individual elements, the AND and XOR gates, for a single rectifying device. It allows a switching between the two gates by a control voltage and thus enables a clocked half adder operation. The logic gates are shown to be reliably operative in a broad noise amplitude range with negligible error probabilities. Subsequently, we study the implementation of the half adder in a combined double-device consisting of two individually tunable rectifiers. We show that this double device allows a simultaneous operation of both relevant gates at once. The presented devices draw their power solely from electronic fluctuations and are therefore an advancement in the field of energy efficient and autonomous electronics. PMID:27079182

  16. Low Power Adder Based Auditory Filter Architecture

    PubMed Central

    Jayanthi, V. S.

    2014-01-01

    Cochlea devices are powered up with the help of batteries and they should possess long working life to avoid replacing of devices at regular interval of years. Hence the devices with low power consumptions are required. In cochlea devices there are numerous filters, each responsible for frequency variant signals, which helps in identifying speech signals of different audible range. In this paper, multiplierless lookup table (LUT) based auditory filter is implemented. Power aware adder architectures are utilized to add the output samples of the LUT, available at every clock cycle. The design is developed and modeled using Verilog HDL, simulated using Mentor Graphics Model-Sim Simulator, and synthesized using Synopsys Design Compiler tool. The design was mapped to TSMC 65 nm technological node. The standard ASIC design methodology has been adapted to carry out the power analysis. The proposed FIR filter architecture has reduced the leakage power by 15% and increased its performance by 2.76%. PMID:25506073

  17. SMILE transmission line adder for RADLAC II

    SciTech Connect

    Mazarakis, M.G.; Poukey, J.W.; Shope, S.L.; Frost, C.A.; Turman, B.N.; Ramirez, J.J.; Prestwich, K.R.; Pankuch, P.J.

    1991-12-31

    SMILE is a coaxial Self Magnetically Insulated Transmission Line voltage adder. It replaces the original beam line of the RADLAC II accelerator by a 12.5 m long cathode electrode. The anode electrode remains practically the same, consisting of the original eight insulating stacks or feeds which are connected with equal diameter stainless steel cylinders. The beam is produced at the end of the accelerator and is free of all the possible instabilities associated with accelerating gaps and magnetic vacuum transport. Annular beams with {beta}{perpendicular} {le} 0.1 and radius r{sub b} {le} 1 cm were routinely obtained and extracted from a small magnetically-immersed foilless electron diode. Results of the experimental evaluation are presented and compared with design parameters and numerical simulation predictions. 4 refs.

  18. SMILE transmission line adder for RADLAC II

    SciTech Connect

    Mazarakis, M.G.; Poukey, J.W.; Shope, S.L.; Frost, C.A.; Turman, B.N.; Ramirez, J.J.; Prestwich, K.R. ); Pankuch, P.J. . Special Projects)

    1991-01-01

    SMILE is a coaxial Self Magnetically Insulated Transmission Line voltage adder. It replaces the original beam line of the RADLAC II accelerator by a 12.5 m long cathode electrode. The anode electrode remains practically the same, consisting of the original eight insulating stacks or feeds which are connected with equal diameter stainless steel cylinders. The beam is produced at the end of the accelerator and is free of all the possible instabilities associated with accelerating gaps and magnetic vacuum transport. Annular beams with {beta}{perpendicular} {le} 0.1 and radius r{sub b} {le} 1 cm were routinely obtained and extracted from a small magnetically-immersed foilless electron diode. Results of the experimental evaluation are presented and compared with design parameters and numerical simulation predictions. 4 refs.

  19. Low power adder based auditory filter architecture.

    PubMed

    Rahiman, P F Khaleelur; Jayanthi, V S

    2014-01-01

    Cochlea devices are powered up with the help of batteries and they should possess long working life to avoid replacing of devices at regular interval of years. Hence the devices with low power consumptions are required. In cochlea devices there are numerous filters, each responsible for frequency variant signals, which helps in identifying speech signals of different audible range. In this paper, multiplierless lookup table (LUT) based auditory filter is implemented. Power aware adder architectures are utilized to add the output samples of the LUT, available at every clock cycle. The design is developed and modeled using Verilog HDL, simulated using Mentor Graphics Model-Sim Simulator, and synthesized using Synopsys Design Compiler tool. The design was mapped to TSMC 65 nm technological node. The standard ASIC design methodology has been adapted to carry out the power analysis. The proposed FIR filter architecture has reduced the leakage power by 15% and increased its performance by 2.76%.

  20. On Design of Parity Preserving Reversible Adder Circuits

    NASA Astrophysics Data System (ADS)

    Haghparast, Majid; Bolhassani, Ali

    2016-08-01

    In this paper novel parity preserving reversible logic blocks are presented and verified. Then, we present cost-effective parity preserving reversible implementations of Full Adder, 4:2 Compressor, Binary to BCD converter, and BCD adder using these blocks. The proposed parity preserving reversible BCD adder is designed by cascading the presented 4-digit parity preserving reversible Full Adder and a parity preserving reversible Binary to BCD Converter. In this design, instead of realizing the detection and correction unit, we design a Binary to BCD converter that its inputs are the output of parity preserving binary adder, and its output is a parity preserving BCD digit. In addition, several theorems on the numbers of garbage outputs, constant inputs, quantum cost and delay of the designs have been presented to show its optimality. In the presented circuits, the delay and the quantum cost are reduced by deriving designs based on the proposed parity preserving reversible blocks. The advantages of the proposed designs over the existing ones are quantitatively described and analysed. All the scales are in the Nano-metric area.

  1. Performance of CMOS ternary full adder at liquid nitrogen temperature

    NASA Astrophysics Data System (ADS)

    Srivastava, A.; Venkatapathy, K.

    We have designed, implemented and studied the performance at liquid nitrogen temperature (77 K) of a CMOS ternary full adder and its building blocks, the simple ternary inverter (STI), positive ternary inverter (PTI) and negative ternary inverter (NTI), and compared the corresponding performance at room temperature (300 K). The ternary full adder has been fabricated in 2 μm, n-well CMOS through MOSIS. In a ternary full adder, the basic building blocks, the PTI and NTI, have been developed using combinations of a CMOS inverter and transmission gate(s). There is close agreement between the simulated and measured voltage transfer characteristics and noise margins of ternary-valued devices. The measured transient times for the NTI, PTI and ternary full adder at 77 K show an improvement by a factor of ≈1.5-2.5 over the corresponding values at 300 K. The present design does not use linear resistors and depletion-mode MOSFETs to implement the ternary full adder and its building blocks, and is fully compatible with current CMOS technology.

  2. Inductive voltage adder (IVA) for submillimeter radius electron beam

    SciTech Connect

    Mazarakis, M.G.; Poukey, J.W.; Maenchen, J.E.

    1996-12-31

    The authors have already demonstrated the utility of inductive voltage adder accelerators for production of small-size electron beams. In this approach, the inductive voltage adder drives a magnetically immersed foilless diode to produce high-energy (10--20 MeV), high-brightness pencil electron beams. This concept was first demonstrated with the successful experiments which converted the linear induction accelerator RADLAC II into an IVA fitted with a small 1-cm radius cathode magnetically immersed foilless diode (RADLAC II/SMILE). They present here first validations of extending this idea to mm-scale electron beams using the SABRE and HERMES-III inductive voltage adders as test beds. The SABRE experiments are already completed and have produced 30-kA, 9-MeV electron beams with envelope diameter of 1.5-mm FWHM. The HERMES-III experiments are currently underway.

  3. Half adder capabilities of a coupled quantum dot device

    NASA Astrophysics Data System (ADS)

    Pfeffer, P.; Hartmann, F.; Neri, I.; Schade, A.; Emmerling, M.; Kamp, M.; Gammaitoni, L.; Höfling, S.; Worschech, L.

    2016-05-01

    In this paper we demonstrate two realizations of a half adder based on a voltage-rectifying mechanism involving two Coulomb-coupled quantum dots. First, we examine the ranges of operation of the half adder’s individual elements, the AND and XOR gates, for a single rectifying device. It allows a switching between the two gates by a control voltage and thus enables a clocked half adder operation. The logic gates are shown to be reliably operative in a broad noise amplitude range with negligible error probabilities. Subsequently, we study the implementation of the half adder in a combined double-device consisting of two individually tunable rectifiers. We show that this double device allows a simultaneous operation of both relevant gates at once. The presented devices draw their power solely from electronic fluctuations and are therefore an advancement in the field of energy efficient and autonomous electronics.

  4. [Bites of venomous snakes in Switzerland].

    PubMed

    Plate, Andreas; Kupferschmidt, Hugo; Schneemann, Markus

    2016-06-01

    Although snake bites are rare in Europe, there are a constant number of snake bites in Switzerland. There are two domestic venomous snakes in Switzerland: the aspic viper (Vipera aspis) and the common European adder (Vipera berus). Bites from venomous snakes are caused either by one of the two domestic venomous snakes or by an exotic venomous snake kept in a terrarium. Snake- bites can cause both a local and/or a systemic envenoming. Potentially fatal systemic complications are related to disturbances of the hemostatic- and cardiovascular system as well as the central or peripheral nervous system. Beside a symptomatic therapy the administration of antivenom is the only causal therapy to neutralize the venomous toxins.

  5. [Bites of venomous snakes in Switzerland].

    PubMed

    Plate, Andreas; Kupferschmidt, Hugo; Schneemann, Markus

    2016-06-01

    Although snake bites are rare in Europe, there are a constant number of snake bites in Switzerland. There are two domestic venomous snakes in Switzerland: the aspic viper (Vipera aspis) and the common European adder (Vipera berus). Bites from venomous snakes are caused either by one of the two domestic venomous snakes or by an exotic venomous snake kept in a terrarium. Snake- bites can cause both a local and/or a systemic envenoming. Potentially fatal systemic complications are related to disturbances of the hemostatic- and cardiovascular system as well as the central or peripheral nervous system. Beside a symptomatic therapy the administration of antivenom is the only causal therapy to neutralize the venomous toxins. PMID:27269771

  6. Excitation of voltage oscillations in an induction voltage adder

    NASA Astrophysics Data System (ADS)

    Bruner, Nichelle; Genoni, Thomas; Madrid, Elizabeth; Welch, Dale; Hahn, Kelly; Oliver, Bryan

    2009-07-01

    The induction voltage adder is an accelerator architecture used in recent designs of pulsed-power driven x-ray radiographic systems such as Sandia National Laboratories’ Radiographic Integrated Test Stand (RITS), the Atomic Weapons Establishment’s planned Hydrus Facility, and the Naval Research Laboratory’s Mercury. Each of these designs relies on magnetic insulation to prevent electron loss across the anode-cathode gap in the vicinity of the adder as well as in the coaxial transmission line. Particle-in-cell simulations of the RITS adder and transmission line show that, as magnetic insulation is being established during a pulse, some electron loss occurs across the gap. Sufficient delay in the cavity pulse timings provides an opportunity for high-momentum electrons to deeply penetrate the cavities of the adder cells where they can excite radio-frequency resonances. These oscillations may be amplified in subsequent gaps, resulting in oscillations in the output power. The specific modes supported by the RITS-6 accelerator and details of the mechanism by which they are excited are presented in this paper.

  7. Decreased serum cholesterol level after snake bite (Vipera palaestinae) as a marker of severity of envenomation.

    PubMed

    Winkler, E; Chovers, M; Almog, S; Pri-Chen, S; Rotenberg, M; Tirosh, M; Ezra, D; Halkin, H

    1993-06-01

    In 44 patients bitten by snakes (Vipera palaestinae), admission serum cholesterol levels were negatively correlated with severity of envenomation (mean +/- SD, 175 +/- 49, 137 +/- 36, and 96 +/- 40 mg/dl, respectively, in cases with mild, moderate, and severe clinical manifestations [p < 0.0001]). Concomitant decreases in serum albumin were not significant. These findings were supported by experimental results in rabbits, in which low, medium, and high doses of purified V. palaestinae venom (all in the non-lethal range), led to dose-dependent decreases in serum cholesterol, at 180 minutes, of 9.5% +/- 8.9%, 18.6% +/- 10.1%, and 32.7% +/- 11.8%, respectively (p < 0.01). This rapid decrease in serum cholesterol level is only partially explained by transcapillary lipoprotein leakage and probably indicates changes in lipoprotein transport and metabolism caused by the phospholipase A2 component of V. palaestinae venom. Admission total serum cholesterol level may serve as an indicator of severity of envenomation in patients bitten by snakes of the Vipera genus before full development of the clinical syndrome. PMID:8505588

  8. INDUCTIVE VOLTAGE ADDER NETWORK ANALYSIS AND MODEL SIMPLIFICATION.

    SciTech Connect

    ZHANG,W.; NG, W.; PAI, C.; SANDBERG, J.; TAN, Y.; TIAN, Y.

    2007-06-17

    Inductive voltage adder topology has attracted great attentions in pulse power community for near two decades. However, there has been lack of literatures on inductive voltage adder network analysis and circuit design model. We have recently developed a simplified model and a set of simple formulas. An expanded model and more detailed analysis are presented in this paper. Our model reveals the relationship of output waveform parameters and hardware designs. Computer simulations have demonstrated that parameter estimation based on this approach is accurate. This approach can be used in early stages of project development to assist feasibility study, geometry selection in engineering design, and parameter selection of critical components. A set of fundamental estimation formulas including system impedance, rise time, and number of stages are presented. This approach is also applicable to induction LINAC design. In addition, the model presented in this paper shows a new topology of high voltage waveform generator.

  9. Optimized parity preserving quantum reversible full adder/subtractor

    NASA Astrophysics Data System (ADS)

    Haghparast, Majid; Bolhassani, Ali

    2016-07-01

    Reversible logic is one of the indispensable aspects of emerging technologies for reducing physical entropy gain, since reversible circuits do not lose information in the form of internal heat during computation. This paper aimed to initiate constructing parity preserving reversible circuits. A novel parity preserving reversible block, HB is presented. Then a new design of a cost-effective parity preserving reversible full adder/subtractor (PPFA/S) is proposed. Next, we suggested a new parity preserving binary to BCD converter. Finally, we proposed new realization of parity preserving reversible BCD adder. The proposed designs are cost-effective in terms of quantum cost and delay. All the scales are in the NANO-metric area.

  10. [Atom-absorption spectrometry in studying of Vipera lebetina obtusa venom].

    PubMed

    Babaev, E T; Abiev, G A; Topchieva, Sh A; Chumburidze, T B; Nemsitsveridze, N G

    2009-09-01

    The aim of the investigation was to work out the atom-absorption spectrometry method for definition of elementary structure of snake venom. The investigation was conducted on venom vipers, caught in the Gobustan district. Determination of heavy metals in venom vipers, was conducted by means of atom-absorption spectrometry (Perkin-Elmer AAS-300). The concentration of the following metals in samples of Vipera Lebetina obtusa venom was defined: Cd (0,012%), (1,234%), Fe (0,487%), Cr (0,171%), Zn (0,78%). The obtained data by means of proposed method of definition of heavy metals in samples of snake venom can be applied to standardize the snake venom, to establish the authenticity in a forensic medical examination, in analyses of medication on the basis of snake venom.

  11. [Influence of electromagnetic radiation on toxicity of Vipera lebetina obtusa venom].

    PubMed

    Abiev, G A; Babaev, E I; Topchieva, Sh A; Chumburidze, T B; Nemsitsveridze, N G

    2009-11-01

    The aim of the article was to study the effect of electromagnetic radiation on toxicity of Vipera lebetina obtusa venom. It was found that mice intoxicated with snake venom, with moderate to high exposure to electromagnetic radiation and mice intoxicated with venom, which had not been exposed to the radiation showed the same symptoms of intoxication and death. At the same time, the longevity of mice intoxicated with venom exposed to electromagnetic radiation was higher. The longevity of mice in control group was 25+/-5 min. The longevity of mice intoxicated with exposed to electromagnetic radiation snake venom was from 29 to 60 min. The research showed that the longevity of mice intoxicated with snake venom rose with the level of electromagnetic radiation intensity the snake was exposed to. Accordingly, snake venom, with exposure to high intensity electromagnetic radiation is less toxic.

  12. Purification and characterization of an organ specific haemorrhagic toxin from Vipera russelli russelli (Russell's viper) venom.

    PubMed

    Kole, L; Chakrabarty, D; Datta, K; Bhattacharyya, D

    2000-04-01

    A haemorrhagic toxin (VRR-12) from Vipera russelli russelli (Russell's viper) venom has been purified by ion-exchange chromatography on CM-Sephadex C-50 followed by size-exclusion HPLC to electrophoretically homogeneous state. It is a 12 kDa single polypeptide having 1 mole of Zn+2 ion. This toxin induces intense intestinal haemorrhage and to a lesser extent skeletal muscle haemorrhage in mice. It does not show detectable proteolytic and esterolytic activity with selected substrates under specified conditions, haemolytic and phospholipase activity. When VRR-12, preincubated with bivalent antiserum against Saw-scaled and Russell's viper venom or EDTA was injected, haemorrhagic activity was not reduced, on the other hand preincubation with phenylmethyl sulphonyl fluoride reduced the activity markedly. Biodistribution studies with 125I VRR-12 show that haemorrhagic manifestation by this toxin is not a direct function of the fraction of the totally administered toxin distributed to that tissue. PMID:10983422

  13. Molecular beacon-based half-adder and half-subtractor.

    PubMed

    Yang, Chia-Ning; Hsu, Chun-Yu; Chuang, Yu-Chung

    2012-01-01

    This work demonstrates two DNA-based logic circuits that behave as a half-adder and a half-subtractor. A half-adder is composed of an AND gate and an XOR gate, whereas a half-subtractor consists of an INH gate and an XOR gate. The proposed designs are inspired by molecular beacons.

  14. Venomics and antivenomics profiles of North African Cerastes cerastes and C. vipera populations reveals a potentially important therapeutic weakness.

    PubMed

    Fahmi, Laila; Makran, Bouchra; Pla, Davinia; Sanz, Libia; Oukkache, Naoual; Lkhider, Mustapha; Harrison, Robert A; Ghalim, Noreddine; Calvete, Juan J

    2012-04-18

    We report the proteomic analysis of the venom of the medically relevant snake, Cerastes cerastes, from Morocco, and the immunoreactivity profile of an experimental monospecific (CcMo_AV against Moroccan C. cerastes venom) and a commercial (Gamma-VIP against Tunisian C. cerastes and M. lebetina venoms) F(ab')(2) antivenoms towards geographic variants of C. cerastes and C. vipera venoms. The venom of C. cerastes is a low-complexity proteome composed of 25-30 toxins belonging to 6 protein families, mainly targetting the hemostatic system. This toxin arsenal explains the clinical picture observed in C. cerastes envenomings. Despite geographic compositional variation, the monospecific CcMo_AV and the Gamma-VIP divalent antivenom produced at Institut Pasteur de Tunis, showed similar immunocapturing capability towards Moroccan, Tunisian, and Egyptian C. cerastes venom proteins. Proteins partially escaping immunorecognition were all identified as PLA(2) molecules. Antivenomic analysis showed low degree of cross-reactivity of Moroccan CcMo_AV and Tunisian Gamma-VIP antivenoms towards C. vipera venom toxins. This study indicates that a more complete therapeutic cover could be achieved by including C. vipera venom in the formulation of venom immunization mixtures, thereby generating a pan-Cerastes antivenom. PMID:22387316

  15. Quantitative transformation for implementation of adder circuits in physical systems.

    PubMed

    Jones, Jeff; Whiting, James G H; Adamatzky, Andrew

    2015-08-01

    Computing devices are composed of spatial arrangements of simple fundamental logic gates. These gates may be combined to form more complex adding circuits and, ultimately, complete computer systems. Implementing classical adding circuits using unconventional, or even living substrates such as slime mould Physarum polycephalum, is made difficult and often impractical by the challenges of branching fan-out of inputs and regions where circuit lines must cross without interference. In this report we explore whether it is possible to avoid spatial propagation, branching and crossing completely in the design of adding circuits. We analyse the input and output patterns of a single-bit full adder circuit. A simple quantitative transformation of the input patterns which considers the total number of bits in the input string allows us to map the respective input combinations to the correct outputs patterns of the full adder circuit, reducing the circuit combinations from a 2:1 mapping to a 1:1 mapping. The mapping of inputs to outputs also shows an incremental linear progression, suggesting its implementation in a range of physical systems. We demonstrate an example implementation, first in simulation, inspired by self-oscillatory dynamics of the acellular slime mould P. polycephalum. We then assess the potential implementation using plasmodium of slime mould itself. This simple transformation may enrich the potential for using unconventional computing substrates to implement digital circuits.

  16. Low Power Adder Based Digital Filter for QRS Detector

    PubMed Central

    Murali, L.; Chitra, D.; Manigandan, T.

    2014-01-01

    Most of the Biomedical applications use dedicated processors for the implementation of complex signal processing. Among them, sensor network is also a type, which has the constraint of low power consumption. Since the processing elements are the most copiously used operations in the signal processors, the power consumption of this has the major impact on the system level application. In this paper, we introduce low power concept of transistor stacking to reduce leakage power; and new architectures based on stacking to implement the full adder and its significance at the digital filter level for QRS detector are implemented. The proposed concept has lesser leakage power at the adder as well as filter level with trade-off in other quality metrics of the design. This enabled the design to be dealt with as the low-power corner and can be made adaptable to any level of hierarchical abstractions as per the requirement of the application. The proposed architectures are designed, modeled at RTL level using the Verilog-HDL, and synthesized in Synopsys Design Compiler by mapping the design to 65 nm technology library standard cells. PMID:24895649

  17. Low power adder based digital filter for QRS detector.

    PubMed

    Murali, L; Chitra, D; Manigandan, T

    2014-01-01

    Most of the Biomedical applications use dedicated processors for the implementation of complex signal processing. Among them, sensor network is also a type, which has the constraint of low power consumption. Since the processing elements are the most copiously used operations in the signal processors, the power consumption of this has the major impact on the system level application. In this paper, we introduce low power concept of transistor stacking to reduce leakage power; and new architectures based on stacking to implement the full adder and its significance at the digital filter level for QRS detector are implemented. The proposed concept has lesser leakage power at the adder as well as filter level with trade-off in other quality metrics of the design. This enabled the design to be dealt with as the low-power corner and can be made adaptable to any level of hierarchical abstractions as per the requirement of the application. The proposed architectures are designed, modeled at RTL level using the Verilog-HDL, and synthesized in Synopsys Design Compiler by mapping the design to 65 nm technology library standard cells.

  18. Quantitative transformation for implementation of adder circuits in physical systems.

    PubMed

    Jones, Jeff; Whiting, James G H; Adamatzky, Andrew

    2015-08-01

    Computing devices are composed of spatial arrangements of simple fundamental logic gates. These gates may be combined to form more complex adding circuits and, ultimately, complete computer systems. Implementing classical adding circuits using unconventional, or even living substrates such as slime mould Physarum polycephalum, is made difficult and often impractical by the challenges of branching fan-out of inputs and regions where circuit lines must cross without interference. In this report we explore whether it is possible to avoid spatial propagation, branching and crossing completely in the design of adding circuits. We analyse the input and output patterns of a single-bit full adder circuit. A simple quantitative transformation of the input patterns which considers the total number of bits in the input string allows us to map the respective input combinations to the correct outputs patterns of the full adder circuit, reducing the circuit combinations from a 2:1 mapping to a 1:1 mapping. The mapping of inputs to outputs also shows an incremental linear progression, suggesting its implementation in a range of physical systems. We demonstrate an example implementation, first in simulation, inspired by self-oscillatory dynamics of the acellular slime mould P. polycephalum. We then assess the potential implementation using plasmodium of slime mould itself. This simple transformation may enrich the potential for using unconventional computing substrates to implement digital circuits. PMID:26007225

  19. Mixed logic style adder circuit designed and fabricated using SOI substrate for irradiation-hardened experiment

    NASA Astrophysics Data System (ADS)

    Yuan, Shoucai; Liu, Yamei

    2016-08-01

    This paper proposed a rail to rail swing, mixed logic style 28-transistor 1-bit full adder circuit which is designed and fabricated using silicon-on-insulator (SOI) substrate with 90 nm gate length technology. The main goal of our design is space application where circuits may be damaged by outer space radiation; so the irradiation-hardened technique such as SOI structure should be used. The circuit's delay, power and power-delay product (PDP) of our proposed gate diffusion input (GDI)-based adder are HSPICE simulated and compared with other reported high-performance 1-bit adder. The GDI-based 1-bit adder has 21.61% improvement in delay and 18.85% improvement in PDP, over the reported 1-bit adder. However, its power dissipation is larger than that reported with 3.56% increased but is still comparable. The worst case performance of proposed 1-bit adder circuit is also seen to be less sensitive to variations in power supply voltage (VDD) and capacitance load (CL), over a wide range from 0.6 to 1.8 V and 0 to 200 fF, respectively. The proposed and reported 1-bit full adders are all layout designed and wafer fabricated with other circuits/systems together on one chip. The chip measurement and analysis has been done at VDD = 1.2 V, CL = 20 fF, and 200 MHz maximum input signal frequency with temperature of 300 K.

  20. Death Adder Envenoming Causes Neurotoxicity Not Reversed by Antivenom - Australian Snakebite Project (ASP-16)

    PubMed Central

    Johnston, Christopher I.; O'Leary, Margaret A.; Brown, Simon G. A.; Currie, Bart J.; Halkidis, Lambros; Whitaker, Richard; Close, Benjamin; Isbister, Geoffrey K.

    2012-01-01

    Background Death adders (Acanthophis spp) are found in Australia, Papua New Guinea and parts of eastern Indonesia. This study aimed to investigate the clinical syndrome of death adder envenoming and response to antivenom treatment. Methodology/Principal Findings Definite death adder bites were recruited from the Australian Snakebite Project (ASP) as defined by expert identification or detection of death adder venom in blood. Clinical effects and laboratory results were collected prospectively, including the time course of neurotoxicity and response to treatment. Enzyme immunoassay was used to measure venom concentrations. Twenty nine patients had definite death adder bites; median age 45 yr (5–74 yr); 25 were male. Envenoming occurred in 14 patients. Two further patients had allergic reactions without envenoming, both snake handlers with previous death adder bites. Of 14 envenomed patients, 12 developed neurotoxicity characterised by ptosis (12), diplopia (9), bulbar weakness (7), intercostal muscle weakness (2) and limb weakness (2). Intubation and mechanical ventilation were required for two patients for 17 and 83 hours. The median time to onset of neurotoxicity was 4 hours (0.5–15.5 hr). One patient bitten by a northern death adder developed myotoxicity and one patient only developed systemic symptoms without neurotoxicity. No patient developed venom induced consumption coagulopathy. Antivenom was administered to 13 patients, all receiving one vial initially. The median time for resolution of neurotoxicity post-antivenom was 21 hours (5–168). The median peak venom concentration in 13 envenomed patients with blood samples was 22 ng/mL (4.4–245 ng/mL). In eight patients where post-antivenom bloods were available, no venom was detected after one vial of antivenom. Conclusions/Significance Death adder envenoming is characterised by neurotoxicity, which is mild in most cases. One vial of death adder antivenom was sufficient to bind all circulating venom. The

  1. [A Rare Case in Hand Surgery: Adder Bite in an Index Finger].

    PubMed

    Jaehn, T; Zunker, C; Mägdefrau, H; Reichert, B

    2016-08-01

    The common European adder is an endangered animal species in Europe. Despite its endangerment, snake bite injuries do occur from time to time, even in Germany. This is a poisoning emergency. Detailed numbers concerning the incidence or lethality of adder bites in Germany do not exist. Only 13% of all cases have a severe course of disease, with children and elderly people prevailing in this patient group. We report the benign course of an adder bite injury of the index finger of a 60-year-old zoologist, which healed completely under symptomatic treatment and surveillance without any operative intervention. PMID:27442002

  2. Impact of cool versus warm temperatures on gestation in the aspic viper (Vipera aspis).

    PubMed

    Michel, Catherine Louise; Pastore, Jean-Henri; Bonnet, Xavier

    2013-07-01

    Previous experimental data suggested that digestion and growth rates are not impaired under cool constant temperature (23°C) in a viviparous snake (Vipera aspis). These results challenged the widespread notion that both elevated temperatures (e.g. 30°C) and temperature fluctuations are required for digestion and growth in temperate climate reptiles. Here, we investigated the impact of constant cool temperatures on another physiological performance that is crucial to population persistence: gestation. At the time when reproductive females were midway through vitellogenesis, we placed ten reproductive and two non-reproductive female aspic vipers at each of two contrasted constant temperature conditions: cool (23°C) versus warm (28°C). Sixty percent of the females placed at 28°C gave birth to healthy offspring, suggesting that constant warm body temperatures were compatible with normal offspring production. Conversely, none of the cool females gave birth to healthy offspring. A blister disease affected exclusively cool pregnant females. Apparently, the combination of cool temperatures plus gestation was too challenging for such females. Our results suggest that reproduction is more thermally sensitive than digestion or growth, indeed gestation faltered under moderately cool thermal constraints. This sensitivity could be a crucial factor determining the capacity of this species to colonize different habitats.

  3. Isolation and preliminary crystallographic studies of two new phospholipases A2 from Vipera nikolskii venom

    PubMed Central

    Gao, Wei; Starkov, Vladislav G.; Tsetlin, Victor I.; Utkin, Yuri N.; Lin, Zheng-jiong; Bi, Ru-chang

    2005-01-01

    Snake-venom phospholipases A2 (PLA2s) represent a good model for studies of structure–function relationships, mainly because of their small size and diverse pharmacological and toxicological activities. To obtain new members of the abundant PLA2 family, the venom of the viper Vipera nikolskii was fractionated for the first time and two new proteins, VN5-3 and VN4-3, were isolated. Both proteins show phospholipase A2 activity and may possess neurotoxic activity. Based on the determined partial amino-acid sequences, the new proteins can be classified as basic Asp49 phospholipases A2. They were crystallized using the hanging-drop vapour-diffusion method and crystals of both proteins belong to space group R32, with similar unit-cell parameters: a = b = 76.29, c = 303.35 Å for protein VN5-3 and a = b = 76.28, c = 304.39 Å for protein VN4-3. Diffraction data sets to 3.0 and 2.2 Å resolution were collected and processed for the VN5-3 and VN4-3 crystals, respectively. Preliminary analysis indicates that there are two molecules in the asymmetric unit for both crystals. Further crystallographic studies will help in understanding the structural basis for the multiple functions of snake-venom PLA2s. PMID:16510990

  4. Design of Efficient Full Adder in Quantum-Dot Cellular Automata

    PubMed Central

    Sen, Bibhash; Sikdar, Biplab K.

    2013-01-01

    Further downscaling of CMOS technology becomes challenging as it faces limitation of feature size reduction. Quantum-dot cellular automata (QCA), a potential alternative to CMOS, promises efficient digital design at nanoscale. Investigations on the reduction of QCA primitives (majority gates and inverters) for various adders are limited, and very few designs exist for reference. As a result, design of adders under QCA framework is gaining its importance in recent research. This work targets developing multi-layered full adder architecture in QCA framework based on five-input majority gate proposed here. A minimum clock zone (2 clock) with high compaction (0.01 μm2) for a full adder around QCA is achieved. Further, the usefulness of such design is established with the synthesis of high-level logic. Experimental results illustrate the significant improvements in design level in terms of circuit area, cell count, and clock compared to that of conventional design approaches. PMID:23844385

  5. A new species of death adder (Acanthophis: Serpentes: Elapidae) from north-western Australia.

    PubMed

    Maddock, Simon T; Ellis, Ryan J; Doughty, Paul; Smith, Lawrence A; Wüster, Wolfgang

    2015-01-01

    Australian death adders (genus Acanthophis) are highly venomous snakes with conservative morphology and sit-and-wait predatory habits, with only moderate taxonomic diversity that nevertheless remains incompletely understood. Analyses of mitochondrial and nuclear gene sequences and morphological characteristics of death adders in northern Australia reveal the existence of a new species from the Kimberley region of Western Australia and the Northern Territory, which we describe as Acanthophis cryptamydros sp. nov. Although populations from the Kimberley were previously considered conspecific with Northern Territory death adders of the A. rugosus complex, our mtDNA analysis indicates that its closest relatives are desert death adders, A. pyrrhus. We found that A. cryptamydros sp. nov. is distinct in both mtDNA and nDNA analysis, and possesses multiple morphological characteristics that allow it to be distinguished from all other Acanthophis species. This study further supports the Kimberley region as an area with high endemic biodiversity.

  6. A SIMPLIFIED APPROACH TO ANALYZE AND MODEL INDUCTIVE VOLTAGE ADDER

    SciTech Connect

    ZHANG,W.; ENG, W.; PAI, C.; SANDBERG, J.; TAN, Y.; TIAN, Y.

    2007-06-25

    We have recently developed a simplified model and a set of simple formulas for inductive voltage adder design. This model reveals the relationship of output waveform parameters and hardware designs. A computer simulation has demonstrated that parameter estimation based on this approach is accurate as compared to an actual circuit. This approach can be used in early stages of project development to assist feasibility study, geometry selection in engineering design, and parameter selection of critical components. In this paper, we give the deduction of a simplified model. Among the estimation formulas we present are those for pulse rise time, system impedance, and number of stages. Examples are used to illustrate the advantage of this approach. This approach is also applicable to induction LINAC design.

  7. Bit-Serial Adder Based on Quantum Dots

    NASA Technical Reports Server (NTRS)

    Fijany, Amir; Toomarian, Nikzad; Modarress, Katayoon; Spotnitz, Mathew

    2003-01-01

    A proposed integrated circuit based on quantum-dot cellular automata (QCA) would function as a bit-serial adder. This circuit would serve as a prototype building block for demonstrating the feasibility of quantum-dots computing and for the further development of increasingly complex and increasingly capable quantum-dots computing circuits. QCA-based bit-serial adders would be especially useful in that they would enable the development of highly parallel and systolic processors for implementing fast Fourier, cosine, Hartley, and wavelet transforms. The proposed circuit would complement the QCA-based circuits described in "Implementing Permutation Matrices by Use of Quantum Dots" (NPO-20801), NASA Tech Briefs, Vol. 25, No. 10 (October 2001), page 42 and "Compact Interconnection Networks Based on Quantum Dots" (NPO-20855), which appears elsewhere in this issue. Those articles described the limitations of very-large-scale-integrated (VLSI) circuitry and the major potential advantage afforded by QCA. To recapitulate: In a VLSI circuit, signal paths that are required not to interact with each other must not cross in the same plane. In contrast, for reasons too complex to describe in the limited space available for this article, suitably designed and operated QCA-based signal paths that are required not to interact with each other can nevertheless be allowed to cross each other in the same plane without adverse effect. In principle, this characteristic could be exploited to design compact, coplanar, simple (relative to VLSI) QCA-based networks to implement complex, advanced interconnection schemes. To enable a meaningful description of the proposed bit-serial adder, it is necessary to further recapitulate the description of a quantum-dot cellular automation from the first-mentioned prior article: A quantum-dot cellular automaton contains four quantum dots positioned at the corners of a square cell. The cell contains two extra mobile electrons that can tunnel (in the

  8. Simple novel all-optical half-adder

    NASA Astrophysics Data System (ADS)

    Chen, Zhixin

    2010-04-01

    On the basis of Sagnac interferometric structure, a simple novel ultrafast scheme of all-optical half-adder is proposed. The structure comprises two of the same balanced terahertz optical asymmetric demultiplexers (TOADs). One TOAD is utilized to achieve an all-optical XOR gate, which is logic SUM. The other is utilized to obtain an all-optical AND gate, which is logic CARRY. Logical SUM and CARRY are simultaneously realized at 80 Gbit/s. Through numerical analysis, the operating characteristics of the scheme are illustrated at 80 Gbit/s. Furthermore, the carrier recovery time of the semiconductor optical amplifier is no longer a crucial parameter to restrict the operation speed of this scheme.

  9. Towards constructing multi-bit binary adder based on Belousov-Zhabotinsky reaction

    NASA Astrophysics Data System (ADS)

    Zhang, Guo-Mao; Wong, Ieong; Chou, Meng-Ta; Zhao, Xin

    2012-04-01

    It has been proposed that the spatial excitable media can perform a wide range of computational operations, from image processing, to path planning, to logical and arithmetic computations. The realizations in the field of chemical logical and arithmetic computations are mainly concerned with single simple logical functions in experiments. In this study, based on Belousov-Zhabotinsky reaction, we performed simulations toward the realization of a more complex operation, the binary adder. Combining with some of the existing functional structures that have been verified experimentally, we designed a planar geometrical binary adder chemical device. Through numerical simulations, we first demonstrated that the device can implement the function of a single-bit full binary adder. Then we show that the binary adder units can be further extended in plane, and coupled together to realize a two-bit, or even multi-bit binary adder. The realization of chemical adders can guide the constructions of other sophisticated arithmetic functions, ultimately leading to the implementation of chemical computer and other intelligent systems.

  10. In vitro screening and evaluation of antivenom phytochemicals from Azima tetracantha Lam. leaves against Bungarus caeruleus and Vipera russelli

    PubMed Central

    2014-01-01

    Background Snakebites are considered a neglected tropical disease that affects thousands of people worldwide. Although antivenom is the only treatment available, it is associated with several side effects. As an alternative, plants have been extensively studied in order to obtain an alternative treatment. In folk medicine, Azima tetracantha Lam. is usually used to treat snakebites. The present study aims to provide a scientific explanation for the use of this plant against snakebite. The extracts of shade dried leaves of A. tetracantha were tested for in vitro inhibitory activity on toxic venom enzymes like phosphomonoesterase, phosphodiesterase, acetylcholinesterase, hyaluronidase etc. from Bungarus caeruleus and Vipera russelli venoms. Results The ethylacetate extract rendered a significant inhibitory effect on the phosphomonoesterase, phosphodiesterase, phospholipase A2 and acetylcholinesterase enzymes. Conclusions The present study suggests that ethylacetate extract of A. tetracantha leaves possesses compounds that inhibit the activity of toxic enzymes from Bungarus caeruleus and Vipera russelli venom. Further pharmacological and in vivo studies would provide evidence that this substance may lead to a potential treatment against these venoms. PMID:24690426

  11. Preliminary evaluation of Vipera palaestinae snake bite treatment in accordance to the severity of the clinical syndrome.

    PubMed

    Shemesh, I Y; Kristal, C; Langerman, L; Bourvin, A

    1998-06-01

    The intravenous administration of a 60 ml dose of Vipera palaestinae antivenin was the suggested standard treatment of every bitten patient. In this study 85 Vipera palaestinae bitten patients where selectively treated with antivenin depending on the severity of the clinical picture. Patients who developed systemic or severe local signs received 20 ml of antivenin over 30 min. If symptoms were still present, an additional 10 ml of antivenin was given until systemic signs subsided. Repeated doses of 10 ml of antivenin was administered in each case of systemic symptom relapse. 49% of patients did not exhibit any systemic symptoms and did not receive antivenin treatment. In 63% of antivenin treated cases symptoms were aborted by a single dose of 20 ml of antivenin. 23% of the antivenin treated patients needed 30-40 ml, 19 needed 50-60 ml and only 1 patient (2%) received 80 ml of drug. Serum sickness complications were found in 44% of antivenin treated patients. The results of this study show that antivenin treatment based on systemic symptoms is effective, required less antivenin than the treatment with fixed dose for each patient and reduces the incidence of serum sickness. PMID:9663693

  12. Do aposematism and Batesian mimicry require bright colours? A test, using European viper markings.

    PubMed Central

    Wüster, Wolfgang; Allum, Christopher S. E.; Bjargardóttir, I. Birta; Bailey, Kimberley L.; Dawson, Karen J.; Guenioui, Jamel; Lewis, John; McGurk, Joe; Moore, Alix G.; Niskanen, Martti; Pollard, Christopher P.

    2004-01-01

    Predator avoidance of noxious prey, aposematism and defensive mimicry are normally associated with bright, contrasting patterns and colours. However, noxious prey may be unable to evolve conspicuous coloration because of other selective constraints, such as the need to be inconspicuous to their own prey or to specialist predators. Many venomous snakes, particularly most vipers, display patterns that are apparently cryptic, but nevertheless highly characteristic, and appear to be mimicked by other, non-venomous snakes. However, predator avoidance of viper patterns has never been demonstrated experimentally. Here, the analysis of 813 avian attacks on 12,636 Plasticine snake models in the field shows that models bearing the characteristic zigzag band of the adder (Vipera berus) are attacked significantly less frequently than plain models. This suggests that predator avoidance of inconspicuously but characteristically patterned noxious prey is possible. Our findings emphasize the importance of mimicry in the ecological and morphological diversification of advanced snakes. PMID:15590601

  13. Do aposematism and Batesian mimicry require bright colours? A test, using European viper markings.

    PubMed

    Wüster, Wolfgang; Allum, Christopher S E; Bjargardóttir, I Birta; Bailey, Kimberley L; Dawson, Karen J; Guenioui, Jamel; Lewis, John; McGurk, Joe; Moore, Alix G; Niskanen, Martti; Pollard, Christopher P

    2004-12-01

    Predator avoidance of noxious prey, aposematism and defensive mimicry are normally associated with bright, contrasting patterns and colours. However, noxious prey may be unable to evolve conspicuous coloration because of other selective constraints, such as the need to be inconspicuous to their own prey or to specialist predators. Many venomous snakes, particularly most vipers, display patterns that are apparently cryptic, but nevertheless highly characteristic, and appear to be mimicked by other, non-venomous snakes. However, predator avoidance of viper patterns has never been demonstrated experimentally. Here, the analysis of 813 avian attacks on 12,636 Plasticine snake models in the field shows that models bearing the characteristic zigzag band of the adder (Vipera berus) are attacked significantly less frequently than plain models. This suggests that predator avoidance of inconspicuously but characteristically patterned noxious prey is possible. Our findings emphasize the importance of mimicry in the ecological and morphological diversification of advanced snakes. PMID:15590601

  14. Design of RSFQ wave pipelined Kogge-Stone Adder and developing custom compound gates

    NASA Astrophysics Data System (ADS)

    Ozer, M.; Eren Çelik, M.; Tukel, Y.; Bozbey, A.

    2014-09-01

    Since the invention of computers, the calculation of arithmetic and logic operations using digital circuits has been one of the leading problems in processor designs. The challenge has been to compute more operations with less clock cycles by using additional specific logic circuits. One of the most fundamental processes is addition; in which the carry bit should be transferred from the least significant bit to the most significant one. A wide range of digital circuit designs have been sustained for specialized faster addition operation. One of these adder algorithms is Kogge Stone Adder which does faster calculation with fewer levels and minimum fan-out compared to today’s adders despite the only disadvantage of having an excessive amount of wiring. In this study, a custom Rapid Single Flux Quantum (RSFQ) based, wave pipelined, Kogge Stone Adder is proposed to be used later in an Arithmetic Logic Unit (ALU). Two different design methodologies have been considered. In the first approach, we used standard logic gates for the whole adder design. In the second approach, utilization to compound gate design with adjustments over component parameters is done by using Particle Swarm Optimization and Statistical Timing Analysis Tools, to increase both efficiency and bias margin.

  15. The symmetric MSD encoder for one-step adder of ternary optical computer

    NASA Astrophysics Data System (ADS)

    Kai, Song; LiPing, Yan

    2016-08-01

    The symmetric Modified Signed-Digit (MSD) encoding is important for achieving the one-step MSD adder of Ternary Optical Computer (TOC). The paper described the symmetric MSD encoding algorithm in detail, and developed its truth table which has nine rows and nine columns. According to the truth table, the state table was developed, and the optical-path structure and circuit-implementation scheme of the symmetric MSD encoder (SME) for one-step adder of TOC were proposed. Finally, a series of experiments were designed and performed. The observed results of the experiments showed that the scheme to implement SME was correct, feasible and efficient.

  16. Development of an Adder-Topology ILC Damping Ring Kicker Modulator

    SciTech Connect

    Tang, Tao; Burkhart, Craig; /SLAC

    2009-05-08

    The ILC damping ring injection and extraction kickers will require high availability modulators that can deliver {+-}5 kV pulses into 50 {Omega} with a 2 ns flattop ({approx}1 ns rise and fall time) at up to 6 MHz. An effort is underway at SLAC National Accelerator Laboratory to meet these requirements using a transmission line adder topology to combine the output of an array of {approx}1 kV modules. The modules employ an ultra-fast hybrid MOSFET/driver that can switch 33 A in 1.2 ns. Experimental results for a scale adder structure are presented.

  17. Modeling of an Inductive Adder Kicker Pulser for a Proton Radiography System

    SciTech Connect

    Wang, L; Caporaso, G J; Cook, E G

    2001-06-12

    An all solid-state kicker pulser for a proton radiography system has been designed. Multiple solid-state modulators stacked in an inductive-adder configuration are utilized in this kicker pulser design. Each modulator is comprised of multiple metal-oxide-semiconductor field-effect transistors (MOSFETs) which quickly switch the energy storage capacitors across a magnetic induction core. Metglas is used as the core material to minimize loss. Voltage from each modulator is inductively added by a voltage summing stalk. A circuit model of a prototype inductive adder kicker pulser modulator has been developed to predict the performance of the pulser modulator. The modeling results are compared with experimental data.

  18. Inductive voltage adder advanced hydrodynamic radiographic technology demonstration

    SciTech Connect

    Mazarakis, M.G.; Poukey, J.W.; Maenchen; Rovang, D.C.

    1997-04-01

    This paper presents the design, results, and analysis of a high-brightness electron beam technology demonstration experiment completed at Sandia National Laboratories, performed in collaboration with Los Alamos National Laboratory. The anticipated electron beam parameters were: 12 MeV, 35-40 kA, 0.5-mm rms radius, and 40-ns full width half maximum (FWHM) pulse duration. This beam, on an optimum thickness tantalum converter, should produce a very intense x-ray source of {approximately} 1.5-mm spot size and 1 kR dose @ 1 m. The accelerator utilized was SABRE, a pulsed inductive voltage adder, and the electron source was a magnetically immersed foilless electron diode. For these experiments, SABRE was modified to high-impedance negative-polarity operation. A new 100-ohm magnetically insulated transmission line cathode electrode was designed and constructed; the cavities were rotated 180{degrees} poloidally to invert the central electrode polarity to negative; and only one of the two pulse forming lines per cavity was energized. A twenty- to thirty-Tesla solenoidal magnet insulated the diode and contained the beam at its extremely small size. These experiments were designed to demonstrate high electron currents in submillimeter radius beams resulting in a high-brightness high-intensity flash x-ray source for high-resolution thick-object hydrodynamic radiography. The SABRE facility high-impedance performance was less than what was hoped. The modifications resulted in a lower amplitude (9 MV), narrower-than-anticipated triangular voltage pulse, which limited the dose to {approximately} 20% of the expected value. In addition, halo and ion-hose instabilities increased the electron beam spot size to > 1.5 mm. Subsequent, more detailed calculations explain these reduced output parameters. An accelerator designed (versus retrofit) for this purpose would provide the desired voltage and pulse shape.

  19. Power efficient, clock gated multiplexer based full adder cell using 28 nm technology

    NASA Astrophysics Data System (ADS)

    Gupta, Ashutosh; Murgai, Shruti; Gulati, Anmol; Kumar, Pradeep

    2016-03-01

    Clock gating is a leading technique used for power saving. Full adders is one of the basic circuit that can be found in maximum VLSI circuits. In this paper clock gated multiplexer based full adder cell is implemented on 28 nm technology. We have designed a full adder cell using a multiplexer with a gated clock without degrading its performance of the cell. We have negative latch circuit for generating gated clock. This gated clock is used to control the multiplexer based full adder cell. The circuit has been synthesized on kintex FPGA through Xilinx ISE Design Suite 14.7 using 28 nm technology in Verilog HDL. The circuit has been simulated on Modelsim 10.3c. The design is verified using System Verilog on QuestaSim in UVM environment. The total power of the circuit has been reduced by 7.41% without degrading the performance of original circuit. The power has been calculated using XPower Analyzer tool of XILINX ISE DESIGN SUITE 14.3.

  20. Power and area-optimised Carry-Select Adder architecture for standard cell-based design

    NASA Astrophysics Data System (ADS)

    Shanmugam, Muthukumar; Choi, GoangSeog

    2015-08-01

    A Carry-Select Adder (CSA) is one of the most suitable adders for high-speed applications, but the power and area penalties are greater, because it requires a double Ripple-Carry Adder (RCA) structure corresponding to carry inputs 0 and 1. Current low-power and low-area techniques are not suitable for a standard cell-based design which is one of the widely adopted design methodologies. Our work proposes two simple optimised architectures suitable for standard cell-based designs. A simple decision logic that replaces the RCA for Carry input 1 in a conventional CSA is proposed. One of the proposed architectures reduces power and area significantly with a small delay penalty compared to the existing techniques. Another proposed architecture improves the speed of operation and reduces the power and area considerably. The first one is more suitable for high-speed arithmetic in battery-operated applications where there is a trade-off between speed and power, while the other one is suitable for high-performance applications which also require area and power optimisation. The proposed architectures were implemented in TSMC 0.18um CMOS technology, and compared with conventional Square Root Carry-Select Adders and an existing standard cell-based design.

  1. A modified prefix operator well suited for area-efficient brick-based adder implementations

    NASA Astrophysics Data System (ADS)

    Rust, I.; Noll, T. G.

    2011-08-01

    The implementation of integrated circuits becomes more and more difficult in the Ultra-Deep-Submicron regime due to sub-wavelength lithography issues. An approach called Brick-Based Design was recently proposed to eliminate the disadvantages of staying with the classical approach to layout design. Prefix adders are a core component in a wide variety of applications due to their high speed and regular topology. In this paper, a modified prefix operator for prefix adders is proposed which is well suited for brick-style layout implementation and, in addition, offers an increase in efficiency. The proposed operator makes it possible to use a mirror gate for the generation of both generate and propagate signals, which exhibits a forbidden input signal combination. This "forbidden state" causes an increase in power dissipation due to transient short circuit currents. The effect of the forbidden state was quantified as part of a comparison against the classical prefix operator, based on 64-bit Sklansky adders implemented in a 40-nm CMOS technology. The effects of the forbidden state were found to be well acceptable. The implementation of the adder based on the proposed prefix operator reduces the area by 29% while increasing the power by 13% compared to one based on the classical operator.

  2. Morphology, Reproduction and Diet in Australian and Papuan Death Adders (Acanthophis, Elapidae)

    PubMed Central

    Shine, Richard; Spencer, Carol L.; Keogh, J. Scott

    2014-01-01

    Death adders (genus Acanthophis) differ from most other elapid snakes, and resemble many viperid snakes, in their thickset morphology and ambush foraging mode. Although these snakes are widely distributed through Australia and Papua New Guinea, their basic biology remains poorly known. We report morphological and ecological data based upon dissection of >750 museum specimens drawn from most of the range of the genus. Female death adders grow larger than conspecific males, to about the same extent in all taxa (20% in mean adult snout-vent length,  =  SVL). Most museum specimens were adult rather than juvenile animals, and adult males outnumbered females in all taxa except A. pyrrhus. Females have shorter tails (relative to SVL) than males, and longer narrower heads (relative to head length) in some but not all species. The southern A. antarcticus is wider-bodied (relative to SVL) than the other Australian species. Fecundity of these viviparous snakes was similar among taxa (mean litter sizes 8 to 14). Death adders encompass a broad range of ecological attributes, taking a wide variety of vertebrate prey, mostly lizards (55%), frogs and mammals (each 21%; based on 217 records). Dietary composition differed among species (e.g. frogs were more common in tropical than temperate-zone species), and shifted with snake body size (endotherms were taken by larger snakes) and sex (male death adders took more lizards than did females). Overall, death adders take a broader array of prey types, including active fast-moving taxa such as endotherms and large diurnal skinks, than do most other Australian elapids of similar body sizes. Ambush foraging is the key to capturing such elusive prey. PMID:24718608

  3. Morphology, reproduction and diet in Australian and Papuan death adders (Acanthophis, Elapidae).

    PubMed

    Shine, Richard; Spencer, Carol L; Keogh, J Scott

    2014-01-01

    Death adders (genus Acanthophis) differ from most other elapid snakes, and resemble many viperid snakes, in their thickset morphology and ambush foraging mode. Although these snakes are widely distributed through Australia and Papua New Guinea, their basic biology remains poorly known. We report morphological and ecological data based upon dissection of >750 museum specimens drawn from most of the range of the genus. Female death adders grow larger than conspecific males, to about the same extent in all taxa (20% in mean adult snout-vent length,  =  SVL). Most museum specimens were adult rather than juvenile animals, and adult males outnumbered females in all taxa except A. pyrrhus. Females have shorter tails (relative to SVL) than males, and longer narrower heads (relative to head length) in some but not all species. The southern A. antarcticus is wider-bodied (relative to SVL) than the other Australian species. Fecundity of these viviparous snakes was similar among taxa (mean litter sizes 8 to 14). Death adders encompass a broad range of ecological attributes, taking a wide variety of vertebrate prey, mostly lizards (55%), frogs and mammals (each 21%; based on 217 records). Dietary composition differed among species (e.g. frogs were more common in tropical than temperate-zone species), and shifted with snake body size (endotherms were taken by larger snakes) and sex (male death adders took more lizards than did females). Overall, death adders take a broader array of prey types, including active fast-moving taxa such as endotherms and large diurnal skinks, than do most other Australian elapids of similar body sizes. Ambush foraging is the key to capturing such elusive prey.

  4. Effects of mild wintering conditions on body mass and corticosterone levels in a temperate reptile, the aspic viper (Vipera aspis).

    PubMed

    Brischoux, François; Dupoué, Andréaz; Lourdais, Olivier; Angelier, Frédéric

    2016-02-01

    Temperate ectotherms are expected to benefit from climate change (e.g., increased activity time), but the impacts of climate warming during the winter have mostly been overlooked. Milder winters are expected to decrease body condition upon emergence, and thus to affect crucial life-history traits, such as survival and reproduction. Mild winter temperature could also trigger a state of chronic physiological stress due to inadequate thermal conditions that preclude both dormancy and activity. We tested these hypotheses on a typical temperate ectothermic vertebrate, the aspic viper (Vipera aspis). We simulated different wintering conditions for three groups of aspic vipers (cold: ~6 °C, mild: ~14 °C and no wintering: ~24 °C) during a one month long period. We found that mild wintering conditions induced a marked decrease in body condition, and provoked an alteration of some hormonal mechanisms involved in emergence. Such effects are likely to bear ultimate consequences on reproduction, and thus population persistence. We emphasize that future studies should incorporate the critical, albeit neglected, winter season when assessing the potential impacts of global changes on ectotherms.

  5. Study on development of Vipera lebetina snake anti-venom in chicken egg yolk for passive immunization

    PubMed Central

    Zolfagharian, Hossein; Dounighi, Naser Mohammadpour

    2015-01-01

    Chicken egg yolk antibodies against Vipera lebetina venom were evaluated for their antivenom potential. White leghorn hens were immunized with detoxified V. lebetina venom (γ-irradiated venom). The detoxified venom (200 μg) was mixed with an equal volume of complete Freund's adjuvant and was injected intramuscularly into the hens. The antibodies showed high activity (1.6 LD50/mL) in egg yolks after 12 d of venom injection. The eggs were collected after 12 days, and the egg yolks were removed and washed with purified water to remove any contamination with egg whites. The purification was performed using a method described by Maya Devi et al., followed by gel filtration (Sephadex G-50). The purity and molecular weight of antivenom antibodies (IgY) were determined using electrophoresis, and the molecular weight was found to be approximately 185 kDa. The potency of IgY was 6 LD50/mL (mice), i.e., 1 mL of IgY could neutralize 43.8 μg of standard V. lebetina venom). Our results showed that chicken egg yolk antibodies were effective in neutralizing the lethality and several pharmacological effects of V. lebetina venom and could be used for developing effective antivenom. PMID:25700656

  6. Fat is sexy for females but not males: the influence of body reserves on reproduction in snakes (Vipera aspis).

    PubMed

    Aubret, Fabien; Bonnet, Xavier; Shine, Richard; Lourdais, Olivier

    2002-09-01

    Reproduction is energetically expensive for both sexes, but the magnitude of expenditure and its relationship to reproductive success differ fundamentally between males and females. Males allocate relatively little to gamete production and, thus, can reproduce successfully with only minor energy investment. In contrast, females of many species experience high fecundity-independent costs of reproduction (such as migration to nesting sites), so they need to amass substantial energy reserves before initiating reproductive activity. Thus, we expect that the relationship between energy reserves and the intensity of reproductive behavior involves a threshold effect in females, but a gradual (or no) effect in males. We tested this prediction using captive vipers (Vipera aspis), dividing both males and females into groups of high versus low body condition. Snakes from each group were placed together and observed for reproductive behavior; sex-steroid levels were also measured. As predicted, females in below-average body condition had very low estradiol levels and did not show sexual receptivity, whereas males of all body condition indices had significant testosterone levels and displayed active courtship. Testosterone levels and courtship intensity increased gradually (i.e., no step function) with body condition in males, but high estradiol levels and sexual receptivity were seen only in females with body reserves above a critical threshold.

  7. Pathophysiological effects of Cerastes cerastes and Vipera lebetina venoms: Immunoneutralization using anti-native and anti-(60)Co irradiated venoms.

    PubMed

    Boumaiza, Sabrina; Oussedik-Oumehdi, Habiba; Laraba-Djebari, Fatima

    2016-01-01

    Cerastes cerastes and Vipera lebetina are the most medically important vipers in Algeria. Their bite induces several pathological effects on victims of accidental envenomation. In this study we analyzed the pathogenesis induced after an experimental envenomation. Indeed, we determined, in vitro, venom enzymatic activities and we analyzed, in vivo, pathological effects induced on liver, heart, lung and skin. In addition we investigated the neutralizing potency of four experimental antivenoms elicited against native and irradiated venoms. Results revealed that V. lebetina and Cerastes cerastes venoms presented strong hemorrhagic, oedematic and necrotic activities. Histopathological study showed that both venoms induced deep damage in tissue structures leading to organ dysfunction. They also increased cellular peroxidases activities, indicating an inflammatory process that is known to amplify tissue damage. Western-blot analysis evidenced that anti-irradiated venoms recognized most components of native venoms. Antivenoms were effective in neutralizing all tested activities, with an increased protective effect obtained with anti-irradiated venoms. Anti-irradiated venoms reduced cellular peroxidases activities indicating a reduction of the inflammatory response. These results may improve our understanding of Algerian Viperidae bite pathogenesis and would encourage further studies planning to provide more proofs on the effectiveness of anti-irradiated venoms administration in the treatment of envenomation. PMID:26678662

  8. Modeling of an inductive adder kicker pulser for DARHT-II

    SciTech Connect

    Wang, L; Caporaso, G J; Cook, E G

    2000-09-25

    An all solid-state kicker pulser for a high current induction accelerator (the Dual-Axis Radiographic Hydrodynamic Test facility DARHT-2) has been designed and fabricated. This kicker pulser uses multiple solid state modulators stacked in an inductive-adder configuration. Each modulator is comprised of multiple metal-oxide-semiconductor field-effect transistors (MOSFETs) which quickly switch the energy storage capacitors across a magnetic induction core. Metglas is used as the core material to minimize loss. Voltage from each modulator is inductively added by a voltage summing stalk and delivered to a 50 ohm output cable. A lumped element circuit model of the inductive adder has been developed to optimize the performance of the pulser. Results for several stalk geometries will be compared with experimental data.

  9. DNA based arithmetic function: a half adder based on DNA strand displacement

    NASA Astrophysics Data System (ADS)

    Li, Wei; Zhang, Fei; Yan, Hao; Liu, Yan

    2016-02-01

    Biomolecular programming utilizes the reactions and information stored in biological molecules, such as proteins and nucleic acids, for computational purposes. DNA has proven itself an excellent candidate for building logic operating systems due to its highly predictable molecular behavior. In this work we designed and realized an XOR logic gate and an AND logic gate based on DNA strand displacement reactions. These logic gates utilize ssDNA as input and output signals. The XOR gate and the AND gate were used as building blocks for constructing a half adder logic circuit, which is a primary step in constructing a full adder, a basic arithmetic unit in computing. This work provides the field of DNA molecular programming with a potential universal arithmetic tool.Biomolecular programming utilizes the reactions and information stored in biological molecules, such as proteins and nucleic acids, for computational purposes. DNA has proven itself an excellent candidate for building logic operating systems due to its highly predictable molecular behavior. In this work we designed and realized an XOR logic gate and an AND logic gate based on DNA strand displacement reactions. These logic gates utilize ssDNA as input and output signals. The XOR gate and the AND gate were used as building blocks for constructing a half adder logic circuit, which is a primary step in constructing a full adder, a basic arithmetic unit in computing. This work provides the field of DNA molecular programming with a potential universal arithmetic tool. Electronic supplementary information (ESI) available: Detailed descriptions of DNA logic gate design, materials and methods, and additional data analysis. See DOI: 10.1039/c5nr08497k

  10. Numerical Simulation of Azimuthal Uniformity of Injection Currents in Single-Point-Feed Induction Voltage Adders

    NASA Astrophysics Data System (ADS)

    WEI, Hao; SUN, Fengju; YIN, Jiahui; HU, Yixiang; LIANG, Tianxue; Peitian, CONG; Aici, QIU

    2015-03-01

    In order to investigate the injection current uniformity around the induction cell bores, two fully electromagnetic (EM) models are respectively established for a single-stage induction cell and an induction voltage adder (IVA) with three cells stacked in series, without considering electron emission. By means of these two models, some factors affecting the injection current uniformity are simulated and analyzed, such as the impedances of adders and loads, cell locations, and feed timing of parallel driving pulses. Simulation results indicate that higher impedances of adder and loads are slightly beneficial to improve injection current uniformity. As the impedances of adder and loads increase from 5 Ω to 30 Ω, the asymmetric coefficient of feed currents decreases from 10.3% to 6.6%. The current non-uniformity within the first cell is a little worse than that in other downstream cells. Simulation results also show that the feed timing would greatly affect current waveforms, and consequently cause some distortion in pulse fronts of cell output voltages. For a given driving pulse with duration time of 70-80 ns, the feed timing with a time deviation of less than 20 ns is acceptable for the three-cell IVAs, just causing the rise time of output voltages to increase about 5 ns at most and making the peak voltage decrease by 3.5%. supported by National Natural Science Foundation of China (No. 51307141), and partly by the State Key Laboratory of Intense Pulsed Radiation Simulation (Northwest Institute of Nuclear Technology) under Contract SKLIPR 1206

  11. Proposed inductive voltage adder based accelerator concepts for the second axis of DARHT

    SciTech Connect

    Smith, D.L.; Johnson, D.L.; Boyes, J.D.

    1997-06-01

    As participants in the Technology Options Study for the second axis of the Dual Axis Radiographic HydroTest (DARHT) facility located at Los Alamos National Laboratories, the authors have considered several accelerator concepts based on the Inductive Voltage Adder (IVA) technology that is being used successfully at Sandia on the SABRE and HERMES-III facilities. The challenging accelerator design requirements for the IVA approach include: {ge}12-MeV beam energy; {approximately}60-ns electrical pulse width; {le}40-kA electron beam current; {approximately}1-mm diameter e-beam; four pulses on the same axis or as close as possible to that axis; and an architecture that fits within the existing building envelope. To satisfy these requirements the IVA concepts take a modular approach. The basic idea is built upon a conservative design for eight ferromagnetically isolated 2-MV cavities that are driven by two 3 to 4-{Omega} water dielectric pulse forming lines (PFLs) synchronized with laser triggered gas switches. The 100-{Omega} vacuum magnetically insulated transmission line (MITL) would taper to a needle cathode that produces the electron beam(s). After considering many concepts the authors narrowed their study to the following options: (A) Four independent single pulse drivers powering four single pulse diodes; (B) Four series adders with interleaved cavities feeding a common MITL and diode; (C) Four stages of series PFLs, isolated from each other by triggered spark gap switches, with single-point feeds to a common adder, MITL, and diode; and (D) Isolated PFLs with multiple-feeds to a common adder using spark gap switches in combination with saturable magnetic cores to isolate the non-energized lines. The authors will discuss these options in greater detail identifying the challenges and risks associated with each.

  12. The need of DNA computing: reversible designs of adders and multipliers using Fredkin gate

    NASA Astrophysics Data System (ADS)

    Thapliyal, Himanshu; Srinivas, M. B.

    2005-12-01

    In recent years, reversible logic has emerged as a promising computing paradigm having its applications in low power computing, quantum computing, nanotechnology, optical computing and DNA computing. The classical set of gates such as AND, OR, and EXOR are not reversible. Recently, it was shown how to encode information in DNA and use DNA amplification to implement Fredkin gates. Furthermore, in the past Fredkin gates have been constructed using DNA, whose outputs are used as inputs for other Fredkin gates. Thus, it can be concluded that arbitrary circuits of Fredkin gates can be constructed using DNA. This has been the driving force leading to the design of reversible adder and multipliers using Fredkin gate. The ripple carry and carry skip adders designed from Fredkin gates already exist in literature; the present work provides an comprehensive extension and novelty to the existing work by introducing the reversible carry look-ahead adder and reversible multipliers using Fredkin gate. The reversible multipliers designed using Fredkin gates are array multiplier, Baugh Wooley multiplier and Wallace tree multiplier. Since, reversible 4:2 compressors are required for the design of reversible Wallace tree multiplier; hence 4:2 compressor is also designed with Fredkin gates. The reversible circuits designed and proposed in this paper form the basis of the ALU of a primitive DNA CPU.

  13. Low impedance z-pinch drivers without post-hole convolute current adders.

    SciTech Connect

    Savage, Mark Edward; Seidel, David Bruce; Mendel, Clifford Will, Jr.

    2009-09-01

    Present-day pulsed-power systems operating in the terawatt regime typically use post-hole convolute current adders to operate at sufficiently low impedance. These adders necessarily involve magnetic nulls that connect the positive and negative electrodes. The resultant loss of magnetic insulation results in electron losses in the vicinity of the nulls that can severely limit the efficiency of the delivery of the system's energy to a load. In this report, we describe an alternate transformer-based approach to obtaining low impedance. The transformer consists of coils whose windings are in parallel rather than in series, and does not suffer from the presence of magnetic nulls. By varying the pitch of the coils windings, the current multiplication ratio can be varied, leading to a more versatile driver. The coupling efficiency of the transformer, its behavior in the presence of electron flow, and its mechanical strength are issues that need to be addressed to evaluate the potential of transformer-based current multiplication as a viable alternative to conventional current adder technology.

  14. An optimal adder-based hardware architecture for the DCT/SA-DCT

    NASA Astrophysics Data System (ADS)

    Kinane, Andrew; Muresan, Valentin; O'Connor, Noel

    2005-07-01

    The explosive growth of the mobile multimedia industry has accentuated the need for ecient VLSI implemen- tations of the associated computationally demanding signal processing algorithms. This need becomes greater as end-users demand increasingly enhanced features and more advanced underpinning video analysis. One such feature is object-based video processing as supported by MPEG-4 core profile, which allows content-based in- teractivity. MPEG-4 has many computationally demanding underlying algorithms, an example of which is the Shape Adaptive Discrete Cosine Transform (SA-DCT). The dynamic nature of the SA-DCT processing steps pose significant VLSI implementation challenges and many of the previously proposed approaches use area and power consumptive multipliers. Most also ignore the subtleties of the packing steps and manipulation of the shape information. We propose a new multiplier-less serial datapath based solely on adders and multiplexers to improve area and power. The adder cost is minimised by employing resource re-use methods. The number of (physical) adders used has been derived using a common sub-expression elimination algorithm. Additional energy eciency is factored into the design by employing guarded evaluation and local clock gating. Our design implements the SA-DCT packing with minimal switching using ecient addressing logic with a transpose mem- ory RAM. The entire design has been synthesized using TSMC 0.09µm TCBN90LP technology yielding a gate count of 12028 for the datapath and its control logic.

  15. Memstor, memstance simulations via a versatile 4-port built with new adder and subtractor circuits

    NASA Astrophysics Data System (ADS)

    Minaei, Shahram; Cem Göknar, Izzet; Yıldız, Merih; Yuce, Erkan

    2015-06-01

    In this paper, novel voltage-mode (VM) n-channel metal-oxide semiconductor (NMOS) transistor-based analogue adder and subtractor circuits, which, respectively, perform V1+V2 and V1-V2 operations, are presented. The most important feature of the proposed circuits is their extremely simple structures containing only six NMOS transistors. Further, the presented adder and subtractor circuits have high input and low output impedances, resulting in easy cascadability. The post-layout simulations of the proposed circuits have been executed using TSMC 0.25 µm process parameters with ±1.25 V. The area of the suggested circuits is approximately 30 × 13 µm2. Moreover, the topology of a generalised mutator, a versatile 4-port built with an adder and a subtractor, which acts as an ordinary mutator when properly reduced to a 2-port, is offered. A table for simulating lossless inductance, memristor, meminductor, memcapacitor and other elements under suitable termination of the 4-port is given, and three of these elements' simulations with SPICE are also presented.

  16. Binary full adder, made of fusion gates, in a subexcitable Belousov-Zhabotinsky system

    NASA Astrophysics Data System (ADS)

    Adamatzky, Andrew

    2015-09-01

    In an excitable thin-layer Belousov-Zhabotinsky (BZ) medium a localized perturbation leads to the formation of omnidirectional target or spiral waves of excitation. A subexcitable BZ medium responds to asymmetric local perturbation by producing traveling localized excitation wave-fragments, distant relatives of dissipative solitons. The size and life span of an excitation wave-fragment depend on the illumination level of the medium. Under the right conditions the wave-fragments conserve their shape and velocity vectors for extended time periods. I interpret the wave-fragments as values of Boolean variables. When two or more wave-fragments collide they annihilate or merge into a new wave-fragment. States of the logic variables, represented by the wave-fragments, are changed in the result of the collision between the wave-fragments. Thus, a logical gate is implemented. Several theoretical designs and experimental laboratory implementations of Boolean logic gates have been proposed in the past but little has been done cascading the gates into binary arithmetical circuits. I propose a unique design of a binary one-bit full adder based on a fusion gate. A fusion gate is a two-input three-output logical device which calculates the conjunction of the input variables and the conjunction of one input variable with the negation of another input variable. The gate is made of three channels: two channels cross each other at an angle, a third channel starts at the junction. The channels contain a BZ medium. When two excitation wave-fragments, traveling towards each other along input channels, collide at the junction they merge into a single wave-front traveling along the third channel. If there is just one wave-front in the input channel, the front continues its propagation undisturbed. I make a one-bit full adder by cascading two fusion gates. I show how to cascade the adder blocks into a many-bit full adder. I evaluate the feasibility of my designs by simulating the evolution

  17. Binary full adder, made of fusion gates, in a subexcitable Belousov-Zhabotinsky system.

    PubMed

    Adamatzky, Andrew

    2015-09-01

    In an excitable thin-layer Belousov-Zhabotinsky (BZ) medium a localized perturbation leads to the formation of omnidirectional target or spiral waves of excitation. A subexcitable BZ medium responds to asymmetric local perturbation by producing traveling localized excitation wave-fragments, distant relatives of dissipative solitons. The size and life span of an excitation wave-fragment depend on the illumination level of the medium. Under the right conditions the wave-fragments conserve their shape and velocity vectors for extended time periods. I interpret the wave-fragments as values of Boolean variables. When two or more wave-fragments collide they annihilate or merge into a new wave-fragment. States of the logic variables, represented by the wave-fragments, are changed in the result of the collision between the wave-fragments. Thus, a logical gate is implemented. Several theoretical designs and experimental laboratory implementations of Boolean logic gates have been proposed in the past but little has been done cascading the gates into binary arithmetical circuits. I propose a unique design of a binary one-bit full adder based on a fusion gate. A fusion gate is a two-input three-output logical device which calculates the conjunction of the input variables and the conjunction of one input variable with the negation of another input variable. The gate is made of three channels: two channels cross each other at an angle, a third channel starts at the junction. The channels contain a BZ medium. When two excitation wave-fragments, traveling towards each other along input channels, collide at the junction they merge into a single wave-front traveling along the third channel. If there is just one wave-front in the input channel, the front continues its propagation undisturbed. I make a one-bit full adder by cascading two fusion gates. I show how to cascade the adder blocks into a many-bit full adder. I evaluate the feasibility of my designs by simulating the evolution

  18. VaSP1, catalytically active serine proteinase from Vipera ammodytes ammodytes venom with unconventional active site triad.

    PubMed

    Kurtović, Tihana; Brgles, Marija; Leonardi, Adrijana; Lang Balija, Maja; Sajevic, Tamara; Križaj, Igor; Allmaier, Günter; Marchetti-Deschmann, Martina; Halassy, Beata

    2014-01-01

    VaSP1, a serine proteinase from Vipera ammodytes ammodytes venom, is a glycosylated monomer of 31.5 kDa, as determined by MALDI mass spectrometry, showing multiple isoelectric points between pH 6.5 and pH 8.5. Partial amino acid sequencing of VaSP1 by Edman degradation and MS/MS analysis identified sequences which allowed its classification among the so-called snake venom serine proteinase homologues, members of the peptidase S1 family, however being devoid of the canonical catalytic triad. Only few representatives of this group have been identified so far with just two of them characterised in detail at the protein level. Despite substitution of His57 with Arg, VaSP1 possesses proteolytic activity which can be inhibited by Pefabloc, benzamidine, Zn²⁺ ions, DTT and trypsin inhibitor II, a Kunitz/BPTI group member. It hydrolyses N(α)-benzoyl-Phe-Val-Arg-p-NA, exhibiting Michaelis-Menten behaviour with K(m) = 48.2 μM and V(m) = 0.019 nM s⁻¹. The pH for optimal activity on tested substrate is around 9.0. VaSP1 also cleaves insulin B-chain, digesting it at positions His¹⁰-Leu¹¹, Ala¹⁴-Leu¹⁵ and Tyr¹⁶-Leu¹⁷. Furthermore, the novel serine proteinase is active towards wide array of proteins involved in haemostasis where its degradation of fibrinogen, fibrin, prothrombin, factor X and plasminogen in vivo probably results in depletion of coagulation factors in blood circulation. The possibility that VaSP1 possesses anticoagulant properties has been further indicated by its ability to prolong prothrombin time and activated partial thromboplastin time.

  19. SMILE'': A Self Magnetically Insulated Transmission LinE adder for the 8-stage RADLAC II accelerator

    SciTech Connect

    Mazarakis, M.G.; Poukey, J.W.; Shope, S.L.; Frost, C.A.; Turman, B.N.; Ramirez, J.J.; Prestwich, K.R. ); Pankuch, P.J. . Special Projects)

    1991-01-01

    The RADLAC II Self Magnetically Insulated Transmission LinE SMILE'' is a coaxial wave guide structure that is composed of two regions: (a) a 9.5-m voltage adder and (b) a 3-m long extension section. The adder section provides for the addition of the input voltages from the individual water-dielectric pulse forming line feeds. The extension section isolates the adder from the magnetically immersed foilless diode electron source load and efficiently transports the pulsed power out from the deionized water tank of the device. The SMILE modification of the RADLAC II accelerator enabled us to produce high quality beams of up to 14 MV, 100 kA. The design and the experimental evaluation of SMILE will be presented and compared with numerical simulation predictions. 12 refs., 9 figs., 1 tab.

  20. Design and code validation of the Jupiter inductive voltage adder (IVA) PRS driver

    SciTech Connect

    Mazarakis, M.G.; Poukey, J.W.; Mendel, C.W.

    1995-07-01

    The proposed Jupiter accelerator is a {approximately} 10-MV, 500-TW system capable of delivering 15-MJ kinetic energy to an imploding plasma radiation source (PRS). The accelerator is based on Hermes-III technology and contains 30 identical inductive voltage adder modules connected in parallel. The modules drive a common circular convolute electrode system in the center of which is located an imploding foil. The relatively high voltage of 8--10 MV is required to compensate for the voltage differential generated across the load due primarily to the fast increase in current (L di/dt) and to lesser extent to the increasing inductance(I dL/dt) and resistive component of the imploding foil. Here we examine the power flow through the device and, in particular, through the voltage adder and long MITL. Analytical models, such as pressure balance and parapotential flow, as well as circuit and PIC codes, were utilized. A new version of the TWOQUICK PIC code, which includes an imploding, cylindrical foil as load, was utilized to compare the power flow calculations done with SCREAMER and TRIFL. The agreement is very satisfactory and adds confidence to the Jupiter design. In addition, an experimental validation of the design is under way this year (FY95) with Hermes III. Long extension MITLs are connected at the end of the voltage adder with inductive and diode loads to benchmark the above design codes. In this paper we outline the accelerator`s conceptual design with emphasis on the power flow and coupling to the inductive load and include preliminary results of Hermes-III experimental design validation.

  1. The mathematics of a quantum Hamiltonian computing half adder Boolean logic gate.

    PubMed

    Dridi, G; Julien, R; Hliwa, M; Joachim, C

    2015-08-28

    The mathematics behind the quantum Hamiltonian computing (QHC) approach of designing Boolean logic gates with a quantum system are given. Using the quantum eigenvalue repulsion effect, the QHC AND, NAND, OR, NOR, XOR, and NXOR Hamiltonian Boolean matrices are constructed. This is applied to the construction of a QHC half adder Hamiltonian matrix requiring only six quantum states to fullfil a half Boolean logical truth table. The QHC design rules open a nano-architectronic way of constructing Boolean logic gates inside a single molecule or atom by atom at the surface of a passivated semi-conductor. PMID:26234709

  2. Optical half-adder and half-subtracter employing the Pockels effect.

    PubMed

    Jiang, Haowei; Chen, Yuping; Li, Guangzhen; Zhu, Chuanyi; Chen, Xianfeng

    2015-04-20

    The Pockels effect in periodically poled lithium niobate made it possible to switch optical signals between two orthogonal optical linear polarizations of the vertical and horizontal polarization states. Based on this effect, we demonstrated polarization-based binary optical logic gates: AND, and OR gates. By combining these basic gates with other polarization-based optical logic gates such as XOR gate accomplished in our previous researches, half-adder and half-subtracter of digital signals with a high extinction ratio of about 10dB have been demonstrated in our experiment, which made it possible to run more complex logical calculus. PMID:25969018

  3. The mathematics of a quantum Hamiltonian computing half adder Boolean logic gate.

    PubMed

    Dridi, G; Julien, R; Hliwa, M; Joachim, C

    2015-08-28

    The mathematics behind the quantum Hamiltonian computing (QHC) approach of designing Boolean logic gates with a quantum system are given. Using the quantum eigenvalue repulsion effect, the QHC AND, NAND, OR, NOR, XOR, and NXOR Hamiltonian Boolean matrices are constructed. This is applied to the construction of a QHC half adder Hamiltonian matrix requiring only six quantum states to fullfil a half Boolean logical truth table. The QHC design rules open a nano-architectronic way of constructing Boolean logic gates inside a single molecule or atom by atom at the surface of a passivated semi-conductor.

  4. The mathematics of a quantum Hamiltonian computing half adder Boolean logic gate

    NASA Astrophysics Data System (ADS)

    Dridi, G.; Julien, R.; Hliwa, M.; Joachim, C.

    2015-08-01

    The mathematics behind the quantum Hamiltonian computing (QHC) approach of designing Boolean logic gates with a quantum system are given. Using the quantum eigenvalue repulsion effect, the QHC AND, NAND, OR, NOR, XOR, and NXOR Hamiltonian Boolean matrices are constructed. This is applied to the construction of a QHC half adder Hamiltonian matrix requiring only six quantum states to fullfil a half Boolean logical truth table. The QHC design rules open a nano-architectronic way of constructing Boolean logic gates inside a single molecule or atom by atom at the surface of a passivated semi-conductor.

  5. An ambusher's arsenal: chemical crypsis in the puff adder (Bitis arietans).

    PubMed

    Miller, Ashadee Kay; Maritz, Bryan; McKay, Shannon; Glaudas, Xavier; Alexander, Graham J

    2015-12-22

    Ambush foragers use a hunting strategy that places them at risk of predation by both visual and olfaction-oriented predators. Resulting selective pressures have driven the evolution of impressive visual crypsis in many ambushing species, and may have led to the development of chemical crypsis. However, unlike for visual crypsis, few studies have attempted to demonstrate chemical crypsis. Field observations of puff adders (Bitis arietans) going undetected by several scent-orientated predator and prey species led us to investigate chemical crypsis in this ambushing species. We trained dogs (Canis familiaris) and meerkats (Suricata suricatta) to test whether a canid and a herpestid predator could detect B. arietans using olfaction. We also tested for chemical crypsis in five species of active foraging snakes, predicted to be easily detectable. Dogs and meerkats unambiguously indicated active foraging species, but failed to correctly indicate puff adder, confirming that B. arietans employs chemical crypsis. This is the first demonstration of chemical crypsis anti-predatory behaviour, though the phenomenon may be widespread among ambushers, especially those that experience high mortality rates owing to predation. Our study provides additional evidence for the existence of an ongoing chemically mediated arms race between predator and prey species. PMID:26674950

  6. An ambusher's arsenal: chemical crypsis in the puff adder (Bitis arietans).

    PubMed

    Miller, Ashadee Kay; Maritz, Bryan; McKay, Shannon; Glaudas, Xavier; Alexander, Graham J

    2015-12-22

    Ambush foragers use a hunting strategy that places them at risk of predation by both visual and olfaction-oriented predators. Resulting selective pressures have driven the evolution of impressive visual crypsis in many ambushing species, and may have led to the development of chemical crypsis. However, unlike for visual crypsis, few studies have attempted to demonstrate chemical crypsis. Field observations of puff adders (Bitis arietans) going undetected by several scent-orientated predator and prey species led us to investigate chemical crypsis in this ambushing species. We trained dogs (Canis familiaris) and meerkats (Suricata suricatta) to test whether a canid and a herpestid predator could detect B. arietans using olfaction. We also tested for chemical crypsis in five species of active foraging snakes, predicted to be easily detectable. Dogs and meerkats unambiguously indicated active foraging species, but failed to correctly indicate puff adder, confirming that B. arietans employs chemical crypsis. This is the first demonstration of chemical crypsis anti-predatory behaviour, though the phenomenon may be widespread among ambushers, especially those that experience high mortality rates owing to predation. Our study provides additional evidence for the existence of an ongoing chemically mediated arms race between predator and prey species.

  7. a High-Level Technique for Estimation and Optimization of Leakage Power for Full Adder

    NASA Astrophysics Data System (ADS)

    Shrivas, Jayram; Akashe, Shyam; Tiwari, Nitesh

    2013-04-01

    Optimization of power is a very important issue in low-voltage and low-power application. In this paper, we have proposed power gating technique to reduce leakage current and leakage power of one-bit full adder. In this power gating technique, we use two sleep transistors i.e., PMOS and NMOS. PMOS sleep transistor is inserted between power supply and pull up network. And NMOS sleep transistor is inserted between pull down network and ground terminal. These sleep transistors (PMOS and NMOS) are turned on when the circuit is working in active mode. And sleep transistors (PMOS and NMOS) are turned off when circuit is working in standby mode. We have simulated one-bit full adder and compared with the power gating technique using cadence virtuoso tool in 45 nm technology at 0.7 V at 27°C. By applying this technique, we have reduced leakage current from 2.935 pA to 1.905 pA and leakage power from 25.04μw to 9.233μw. By using this technique, we have reduced leakage power up to 63.12%.

  8. 18 CFR 35.22 - Limits for percentage adders in rates for transmission services; revision of rate schedules...

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... that performs a transmission or purchase and resale function for electric power generated by another... 18 Conservation of Power and Water Resources 1 2010-04-01 2010-04-01 false Limits for percentage adders in rates for transmission services; revision of rate schedules, tariffs or service agreements....

  9. 18 CFR 35.22 - Limits for percentage adders in rates for transmission services; revision of rate schedules...

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... that performs a transmission or purchase and resale function for electric power generated by another... 18 Conservation of Power and Water Resources 1 2011-04-01 2011-04-01 false Limits for percentage adders in rates for transmission services; revision of rate schedules, tariffs or service agreements....

  10. Butterfly interconnection implementation for an n-bit parallel full adder/subtractor

    NASA Astrophysics Data System (ADS)

    Sun, De-Gui; Xiang, Qian; Wang, Na-Xin; Weng, Zhao-Heng

    1992-07-01

    Free-space optical interconnections are important in both massive digital optical computing and communication systems. The architectural features of three interconnection networks are analyzed and compared, and the optical butterfly interconnection is shown to have many advantages over other interconnections in implementing various basic logic functions such as addition, subtraction, multiplication, and fast Fourier transforms. Starting with conventional Karnaugh maps and Boolean algebra, the characteristics of full addition and full subtraction are analyzed and compared. An n-bit parallel calculator that can implement both ripple carry full additions and ripple borrow full subtractions using multilayer butterfly interconnection networks is designed. Then the schematic and architecture of the full adder/subtractor, interconnection networks, and the patterns of key devices such as masks to implement AND and OR operations in this calculation are described in detail. The correct simulation results of several groups of multibit digits are provided. Finally, the development of the interconnections in implementing logic operations is discussed.

  11. Toward defect guard-banding of EUV exposures by full chip optical wafer inspection of EUV mask defect adders

    NASA Astrophysics Data System (ADS)

    Halle, Scott D.; Meli, Luciana; Delancey, Robert; Vemareddy, Kaushik; Crispo, Gary; Bonam, Ravi; Burkhardt, Martin; Corliss, Daniel

    2015-03-01

    The detection of EUV mask adder defects has been investigated with an optical wafer defect inspection system employing a methodology termed Die-to-"golden" Virtual Reference Die (D2VRD). Both opaque and clear type mask absorber programmed defects were inspected and characterized over a range of defect sizes, down to (4x mask) 40 nm. The D2VRD inspection system was capable of identifying the corresponding wafer print defects down to the limit of the defect printability threshold at approximately 30 nm (1x wafer). The efficacy of the D2VRD scheme on full chip wafer inspection to suppress random process defects and identify real mask defects is demonstrated. Using defect repeater analysis and patch image classification of both the reference die and the scanned die enables the unambiguous identification of mask adder defects.

  12. Development of an optical parallel logic device and a half-adder circuit for digital optical processing

    NASA Technical Reports Server (NTRS)

    Athale, R. A.; Lee, S. H.

    1978-01-01

    The paper describes the fabrication and operation of an optical parallel logic (OPAL) device which performs Boolean algebraic operations on binary images. Several logic operations on two input binary images were demonstrated using an 8 x 8 device with a CdS photoconductor and a twisted nematic liquid crystal. Two such OPAL devices can be interconnected to form a half-adder circuit which is one of the essential components of a CPU in a digital signal processor.

  13. Resembling a viper: implications of mimicry for conservation of the endangered smooth snake.

    PubMed

    Valkonen, Janne K; Mappes, Johanna

    2014-12-01

    The phenomenon of Batesian mimicry, where a palatable animal gains protection against predation by resembling an unpalatable model, has been a core interest of evolutionary biologists for 150 years. An extensive range of studies has focused on revealing mechanistic aspects of mimicry (shared education and generalization of predators) and the evolutionary dynamics of mimicry systems (co-operation vs. conflict) and revealed that protective mimicry is widespread and is important for individual fitness. However, according to our knowledge, there are no case studies where mimicry theories have been applied to conservation of mimetic species. Theoretically, mimicry affects, for example, frequency dependency of predator avoidance learning and human induced mortality. We examined the case of the protected, endangered, nonvenomous smooth snake (Coronella austriaca) that mimics the nonprotected venomous adder (Vipera berus), both of which occur in the Åland archipelago, Finland. To quantify the added predation risk on smooth snakes caused by the rarity of vipers, we calculated risk estimates from experimental data. Resemblance of vipers enhances survival of smooth snakes against bird predation because many predators avoid touching venomous vipers. Mimetic resemblance is however disadvantageous against human predators, who kill venomous vipers and accidentally kill endangered, protected smooth snakes. We found that the effective population size of the adders in Åland is very low relative to its smooth snake mimic (28.93 and 41.35, respectively).Because Batesian mimicry is advantageous for the mimic only if model species exist in sufficiently high numbers, it is likely that the conservation program for smooth snakes will fail if adders continue to be destroyed. Understanding the population consequences of mimetic species may be crucial to the success of endangered species conservation. We suggest that when a Batesian mimic requires protection, conservation planners should

  14. A new linear inductive voltage adder driver for the Saturn Accelerator

    SciTech Connect

    Mazarakis, M.G.; Spielman, R.B.; Struve, K.W.; Long, F.W.

    2000-08-09

    Saturn is a dual-purpose accelerator. It can be operated as a large-area flash x-ray source for simulation testing or as a Z-pinch driver especially for K-line x-ray production. In the first mode, the accelerator is fitted with three concentric-ring 2-MV electron diodes, while in the Z-pinch mode the current of all the modules is combined via a post-hole convolute arrangement and driven through a cylindrical array of very fine wires. We present here a point design for a new Saturn class driver based on a number of linear inductive voltage adders connected in parallel. A technology recently implemented at the Institute of High Current Electronics in Tomsk (Russia) is being utilized. In the present design we eliminate Marx generators and pulse-forming networks. Each inductive voltage adder cavity is directly fed by a number of fast 100-kV small-size capacitors arranged in a circular array around each accelerating gap. The number of capacitors connected in parallel to each cavity defines the total maximum current. By selecting low inductance switches, voltage pulses as short as 30-50-ns FWHM can be directly achieved. The voltage of each stage is low (100-200 kv). Many stages are required to achieve multi-megavolt accelerator output. However, since the length of each stage is very short (4-10 cm), accelerating gradients of higher than 1 MV/m can easily be obtained. The proposed new driver will be capable of delivering pulses of 15-MA, 36-TW, 1.2-MJ to the diode load, with a peak voltage of {minus}2.2 MV and FWHM of 40-ns. And although its performance will exceed the presently utilized driver, its size and cost could be much smaller ({approximately}1/3). In addition, no liquid dielectrics like oil or deionized water will be required. Even elimination of ferromagnetic material (by using air-core cavities) is a possibility.

  15. Inductive Voltage Adder Driven X-Ray Sources for Hydrodynamic Radiography

    SciTech Connect

    Bailey, V.; Cordova, S.; Droemer, D.; Gustwiller, J.; Hunt, E.; Johnson, D.L.; MacLeod, G.; Maenchen, John; Menge, P.; Molina, I.; Oliver, B; Olson, C.; Rosenthal, S; Rovang, D.; Smith, I.; Welch, D.; Woo, L.

    1999-06-17

    Inductive Voltage Adder (IVA) accelerators were developed to provide high-current (100s of kA) power pulses at high voltage (up to 20 MV) using robust modular components. This architecture simultaneously resolves problems found in conventional pulsed and linear induction accelerators. A variety of high-brightness pulsed x-ray radiographic sources are needed from sub-megavolt to 16-MeV endpoints with greater source brightness (dose/spot) than presently available. We are applying IVA systems to produce very intense (up to 75 TW/cm{sup 2}) electron beams for these flash radiographic applications. The accelerator electromagnetic pulse is converted to a directed electron beam at the end of a self-magnetically insulated vacuum transmission line. The cantilevered cathode threading the accelerator cavities terminates in a small (1-mm diameter) needle, producing the electron beam which is transported to a grounded bremsstrahlung converter within a strong ({approximately}50-T) axial magnetic field. These systems produce mm-sized stable electron beams, yielding very intense x-ray sources. Detailed simulations of the electron beam generation, transport, and target interaction are presented along with scaling laws for the radiation production and x-ray spot size. Experimental studies confirm these simulations and show this reliable, compact, and inexpensive technology scales to 1000-R doses a meter from a mm-diameter source in 50 ns.

  16. SplAdder: identification, quantification and testing of alternative splicing events from RNA-Seq data

    PubMed Central

    Kahles, André; Ong, Cheng Soon; Zhong, Yi; Rätsch, Gunnar

    2016-01-01

    Motivation: Understanding the occurrence and regulation of alternative splicing (AS) is a key task towards explaining the regulatory processes that shape the complex transcriptomes of higher eukaryotes. With the advent of high-throughput sequencing of RNA (RNA-Seq), the diversity of AS transcripts could be measured at an unprecedented depth. Although the catalog of known AS events has grown ever since, novel transcripts are commonly observed when working with less well annotated organisms, in the context of disease, or within large populations. Whereas an identification of complete transcripts is technically challenging and computationally expensive, focusing on single splicing events as a proxy for transcriptome characteristics is fruitful and sufficient for a wide range of analyses. Results: We present SplAdder, an alternative splicing toolbox, that takes RNA-Seq alignments and an annotation file as input to (i) augment the annotation based on RNA-Seq evidence, (ii) identify alternative splicing events present in the augmented annotation graph, (iii) quantify and confirm these events based on the RNA-Seq data and (iv) test for significant quantitative differences between samples. Thereby, our main focus lies on performance, accuracy and usability. Availability: Source code and documentation are available for download at http://github.com/ratschlab/spladder. Example data, introductory information and a small tutorial are accessible via http://bioweb.me/spladder. Contacts: andre.kahles@ratschlab.org or gunnar.ratsch@ratschlab.org Supplementary information: Supplementary data are available at Bioinformatics online. PMID:26873928

  17. Towards constructing one-bit binary adder in excitable chemical medium

    NASA Astrophysics Data System (ADS)

    Lacy Costello, Ben De; Adamatzky, Andy; Jahan, Ishrat; Zhang, Liang

    2011-03-01

    The light-sensitive modification (ruthenium catalysed) of the Belousov-Zhabotinsky reaction exhibits various excitability regimes depending on the level of illumination. Within a narrow range of applied illumination levels the medium is in a sub-excitable state. When in this state an asymmetric perturbation of the medium leads to formation of a travelling localized excitation (wave-fragment) which moves along a predetermined trajectory, ideally preserving its shape and velocity over an extended time period. Collision-based computing can be implemented with these wave-fragments whereby values of Boolean variables are represented as the presence/absence of a wave-fragment at specific sites. When two wave-fragments collide they either annihilate, or form new wave-fragments. The trajectories of the wave-fragments after the collision represent the result of a computation, e.g. construction of a simple logical gate. However, wave-fragments in sub-excitable chemical media are difficult to control. Therefore, we adopted a hybrid procedure in order to construct collision-based logical gates. We used channels of low light intensity projected onto the excitable media in order to subtly tune and stabilise the propagating wave-fragments allowing them to collide at the junctions between channels. Using this methodology we were able to implement both in theoretical models (using the Oregonator) and in experiment two interaction-based logical gates and assemble the gates into a basic one-bit binary adder. We present the first ever experimental approach towards constructing arithmetic circuits in spatially-extended excitable chemical systems where light is used to impart functionality.

  18. Characterization of Salmonella isolated from captive and free-living snakes in Germany.

    PubMed

    Krautwald-Junghanns, Maria-Elisabeth; Stenkat, Julia; Szabo, Istvan; Ortlieb, Falk; Blindow, Irmgard; Neul, Ann-Kathrin; Pees, Michael; Schmidt, Volker

    2013-01-01

    Reptiles are well-known reservoirs of Salmonella spp. and cases of reptile-associated salmonellosis (RAS) are increasing since reptiles are becoming more popular as pets. In the present study, the presence, distribution and prevalence of serovars of Salmonella was investigated in captive snakes (n = 87) and in free-living snakes (n = 87) in Germany. A total of 43 S. enterica-isolates were recovered from organ samples and cloacal swabs, predominantly belonging to the subspecies diarizonae (IIIb) (n = 27), enterica (I) (n = 7) and houtenae (IV) (n = 6). S. enterica subsp. enterica (I) serovar Paratyphi B (n = 4) and S. enterica subsp. diarizonae (IIIb) serovar 47:l,v:z (n = 3) were the most frequently isolated serotypes. Nevertheless, the fact that most serotypes were only represented by a single isolate points out the high diversity of Salmonella present among snakes. Salmonella enterica subsp. diarizonae (IIIb) serotype 40:i:z53, which was isolated twice from two free-living Eurasian adders (Vipera berus) captured at different locations, has not been previously described. Our results confirm the role of both free-living and captive snakes as reservoirs of S. enterica in Germany.

  19. Recognition of Vipera ammodytes meridionalis neurotoxin vipoxin and its components using phage-displayed scFv and polyclonal antivenom sera.

    PubMed

    Stoyanova, Vishnya; Aleksandrov, Radoslav; Lukarska, Maria; Duhalov, Deyan; Atanasov, Vasil; Petrova, Svetla

    2012-10-01

    Vipoxin is a potent postsynaptic heterodimeric neurotoxin isolated from the venom of the Bulgarian snake Vipera ammodytes meridionalis, whose snakebites cause different and strongly manifested pathophysiological effects (neurotoxic, hemolytic, anticoagulant, convulsant, hypotensive, hyperglycemic etc.). The neutralization of snake toxins calls for extensive research through the application of different approaches: antibodies, non-immunologic inhibitors, natural products derived from plants and animals, as well as synthetic drugs. In this study, we applied naive Tomlinson I + J (Cambridge, UK) libraries to obtain recombinant human scFv antibodies against the vipoxin's two subunits--basic and toxic phospholipase A₂ (PLA₂) and acidic, non-toxic component. We found that 33 of more than hundred tested clones were positive and recognized vipoxin and its subunits. Enriched scFv-phage samples (1.2 × 10⁹ pfu/ml) were analyzed for their binding (ELISA) and enzyme-inhibiting abilities. Single chain Fv-phage clones--D₁₂, E₃, F₆, D₁₀ and G₅ exhihest binding affinity for the toxic component. Clones A₁, D₁₂ and C₁₂ recognized preferentially vipoxin's acidic component. Clones E₃, G₅ and H₄ inhibited the enzymatic activity of both vipoxin and its purified and separated toxic subunit to the highest extent. Six of the selected clones (E₃, G₅, H₄, C₁₂, D₁₀ and A₁₁) inhibited direct hemolytic activity of vipoxin and its pure PLA₂ subunit. The obtained specific scFv antibodies will be used for epitope mapping studies required to shed light on the role of the phospholipase A₂ activity for the vipoxin toxicity and its effective neutralization.

  20. Complete structure of an increasing capillary permeability protein (ICPP) purified from Vipera lebetina venom. ICPP is angiogenic via vascular endothelial growth factor receptor signalling.

    PubMed

    Gasmi, Ammar; Bourcier, Christine; Aloui, Zohra; Srairi, Najet; Marchetti, Sandrine; Gimond, Clotilde; Wedge, Stephen R; Hennequin, Laurent; Pouysségur, Jacques

    2002-08-16

    The partial sequence of the increasing capillary permeability protein (ICPP) purified from Vipera lebetina venom revealed a strong homology to vascular endothelial growth factor (VEGF)-A. We now report its complete amino acid sequence determined by Edman degradation and its biological effects on mouse and human vascular endothelial cells. ICPP is a homodimeric protein linked by cysteine disulfide bonds of 25115 Da revealed by mass spectrometry. Each monomer is composed of 110 amino acids including eight cysteine residues and a pyroglutamic acid at the N-terminal extremity. ICPP shares 52% sequence identity with human VEGF but lacks the heparin binding domain and Asn glycosylation site. Besides its strong capillary permeability activity, ICPP was found to be a potent in vitro angiogenic factor when added to mouse embryonic stem cells or human umbilical vein endothelial cells. ICPP was found to be as potent as human VEGF165 in activating p42/p44 MAPK, in reinitiation of DNA synthesis in human umbilical vein endothelial cells, and in promoting in vitro angiogenesis of mouse embryonic stem cells. All these biological actions, including capillary permeability in mice, were fully inhibited by 1 microm of a new specific VEGF receptor tyrosine kinase inhibitor (ZM317450) from AstraZeneca that belongs to the anilinocinnoline family of compounds. Indeed, up to a 30 times higher concentration of inhibitor did not affect platelet-derived growth factor, epidermal growth factor, FGF-2, insulin, alpha-thrombin, or fetal calf serum-induced p42/p44 MAPK and reinitiation of DNA synthesis. Therefore, we conclude that this venom-derived ICPP exerts its biological action (permeability and angiogenesis) through activation of VEGF receptor signaling (VEGF-R2 and possibly VEGF-R1).

  1. Ion diode performance on a positive polarity inductive voltage adder with layered magnetically insulated transmission line flow

    SciTech Connect

    Hinshelwood, D. D.; Schumer, J. W.; Allen, R. J.; Commisso, R. J.; Jackson, S. L.; Murphy, D. P.; Phipps, D.; Swanekamp, S. B.; Weber, B. V.; Ottinger, P. F.; Apruzese, J. P.; Cooperstein, G.; Young, F. C.

    2011-05-15

    A pinch-reflex ion diode is fielded on the pulsed-power machine Mercury (R. J. Allen, et al., 15th IEEE Intl. Pulsed Power Conf., Monterey, CA, 2005, p. 339), which has an inductive voltage adder (IVA) architecture and a magnetically insulated transmission line (MITL). Mercury is operated in positive polarity resulting in layered MITL flow as emitted electrons are born at a different potential in each of the adder cavities. The usual method for estimating the voltage by measuring the bound current in the cathode and anode of the MITL is not accurate with layered flow, and the interaction of the MITL flow with a pinched-beam ion diode load has not been studied previously. Other methods for determining the diode voltage are applied, ion diode performance is experimentally characterized and evaluated, and circuit and particle-in-cell (PIC) simulations are performed. Results indicate that the ion diode couples efficiently to the machine operating at a diode voltage of about 3.5 MV and a total current of about 325 kA, with an ion current of about 70 kA of which about 60 kA is proton current. It is also found that the layered flow impedance of the MITL is about half the vacuum impedance.

  2. A pulsed-power generator merging inductive voltage and current adders and its switch trigger application example.

    PubMed

    Li, Lee; Yafeng, Ge; Heqin, Zhong; Bin, Yu; Longjun, Xie

    2013-07-01

    A pulsed-power generator using inductive adder technology is proposed for the case of a discharge gap. The merit of this generator is to merge the pulsed-voltage and pulsed-current adders via the dual secondary windings with special circuit. For the nonlinear impedance in any discharge gap, the standalone voltage-pulse and current-pulse can be outputted successively by this generator. The proposed generator is especially useful for the common resolution of implementing pulse discharge at less cost. As an application example, a compact trigger prototype was developed to compatibly use in the gas-insulated and vacuum switches. Experiments achieved good results that the triggered switches showed stable performance and long life. If the basic circuit of this proposed generator is regarded as a pulsed-generating unit, a certain number of such units connected in parallel can be expected to form a general device with generating greater breakdown-voltage and sustained-current pulses for discharge gaps.

  3. Quantum dot ternary-valued full-adder: Logic synthesis by a multiobjective design optimization based on a genetic algorithm

    SciTech Connect

    Klymenko, M. V.; Remacle, F.

    2014-10-28

    A methodology is proposed for designing a low-energy consuming ternary-valued full adder based on a quantum dot (QD) electrostatically coupled with a single electron transistor operating as a charge sensor. The methodology is based on design optimization: the values of the physical parameters of the system required for implementing the logic operations are optimized using a multiobjective genetic algorithm. The searching space is determined by elements of the capacitance matrix describing the electrostatic couplings in the entire device. The objective functions are defined as the maximal absolute error over actual device logic outputs relative to the ideal truth tables for the sum and the carry-out in base 3. The logic units are implemented on the same device: a single dual-gate quantum dot and a charge sensor. Their physical parameters are optimized to compute either the sum or the carry out outputs and are compatible with current experimental capabilities. The outputs are encoded in the value of the electric current passing through the charge sensor, while the logic inputs are supplied by the voltage levels on the two gate electrodes attached to the QD. The complex logic ternary operations are directly implemented on an extremely simple device, characterized by small sizes and low-energy consumption compared to devices based on switching single-electron transistors. The design methodology is general and provides a rational approach for realizing non-switching logic operations on QD devices.

  4. Cold climate specialization: adaptive covariation between metabolic rate and thermoregulation in pregnant vipers.

    PubMed

    Lourdais, Olivier; Guillon, Michaël; Denardo, Dale; Blouin-Demers, Gabriel

    2013-07-01

    We compared thermoregulatory strategies during pregnancy in two congeneric viperid snakes (Vipera berus and Vipera aspis) with parapatric geographic ranges. V. berus is a boreal specialist with the largest known distribution among terrestrial snakes while V. aspis is a south-European species. Despite contrasted climatic affinities, the two species displayed identical thermal preferences (Tset) in a laboratory thermal gradient. Under identical natural conditions, however, V. berus was capable of maintaining Tset for longer periods, especially when the weather was constraining. Consistent with the metabolic cold adaptation hypothesis, V. berus displayed higher standard metabolic rate at all temperatures considered. We used the thermal dependence of metabolic rate to calculate daily metabolic profiles from body temperature under natural conditions. The boreal specialist experienced higher daily metabolic rate and minimized gestation duration chiefly because of differences in the metabolic reaction norms, but also superior thermoregulatory efficiency. Under cold climates, thermal constraints should make precise thermoregulation costly. However, a shift in the metabolic reaction norm may compensate for thermal constraints and modify the cost-benefit balance of thermoregulation. Covariation between metabolic rate and thermoregulation efficiency is likely an important adaptation to cold climates.

  5. Fast Differential Adder

    NASA Technical Reports Server (NTRS)

    Arditti, Mort A.; Silva, Rosemary

    1993-01-01

    Differential adding circuit (or, equivalently, subtracting circuit) faster and consumes less power because it contains only one differential amplifier. Suitable for use in high-frequency-switching, high power-regulating circuit.

  6. Experiments investigating the generation and transport of 10--12 MeV, 30-kA, mm-size electron beams with linear inductive voltage adders

    SciTech Connect

    Mazarakis, M.G.; Poukey, J.W.; Maenchen, J.E.

    1997-06-01

    The authors present the design, analysis, and results of the high-brightness electron beam experiments currently under investigation at Sandia National Laboratories. The anticipated beam parameters are the following: 8--12 MeV, 35--50 kA, 30--60 ns FWHM, and 0.5-mm rms beam radius. The accelerators utilized are SABRE and HERMES III. Both are linear inductive voltage adders modified to higher impedance and fitted with magnetically immersed foil less electron diodes. In the strong 20--50 Tesla solenoidal magnetic field of the diode, mm-size electron beams are generated and propagated to a beam stop. The electron beam is field emitted from mm-diameter needle-shaped cathode electrode and is contained in a similar size envelop by the strong magnetic field. These extremely space charge dominated beams provide the opportunity to study beam dynamics and possible instabilities in a unique parameter space. The SABRE experiments are already completed and have produced 30-kA, 1.5-mm FWHM electron beams, while the HERMES-III experiments are on-going.

  7. The effect of physiological levels of South African puff adder (Bitis arietans) snake venom on blood cells: an in vitro model

    PubMed Central

    Strydom, Morné A.; Bester, Janette; Mbotwe, Sthembile; Pretorius, Etheresia

    2016-01-01

    A significant burden of illness is caused globally by snakebites particularly by the puff adder, Bitis arietans. Presently there is no reliable and rapid method to confirm envenomation on blood chemistry; although coagulation parameters like prothrombin time, partial thromboplastin time, international normalized ratio and also serum electrolytes are tested. Here, we found that direct in vitro exposure of physiological relevant whole venom levels to human healthy blood (N = 32), caused significant physiological changes to platelet activity using a hematology analyzer, and measuring occlusion time, as well as lyses time, with the global thrombosis test (GTT). Disintegrated platelets were confirmed by scanning electron microscopy (SEM). We also confirmed the pathologic effects on erythrocytes (RBCs) (visible as eryptotic RBCs), by looking at both light microscopy and SEM. Thromboelastography showed that no clot formation in whole blood could be induced after addition of whole venom. We propose further clinical studies to investigate the use of light microscopy smears and hematology analyzer results immediately after envenomation, as a possible first-stage of clinical confirmation of envenomation. PMID:27775063

  8. Isolation and characterisation of P-EPTX-Ap1a and P-EPTX-Ar1a: pre-synaptic neurotoxins from the venom of the northern (Acanthophis praelongus) and Irian Jayan (Acanthophis rugosus) death adders.

    PubMed

    Chaisakul, Janeyuth; Konstantakopoulos, Nicki; Smith, A Ian; Hodgson, Wayne C

    2010-09-15

    The neurotoxicity observed following death adder envenoming has been thought to be solely due to the presence of potent post-synaptic neurotoxins. Clinically, these effects are often poorly reversed by death adder antivenom or anticholinesterase, particularly when patients present with established paralysis. This suggests that either the post-synaptic neurotoxins are irreversible/'pseudo' irreversible, or the venom contains pre-synaptic neurotoxins that do not respond to antivenom. To support the later hypothesis, a pre-synaptic neurotoxin (P-EPTX-Aa1a) has recently been isolated from the venom of Acanthophis antarcticus. We examined Acanthophis praelongus and Acanthophis rugosus venoms for the presence of pre-synaptic neurotoxins. P-EPTX-Ap1a (40,719Da) and P-EPTX-Ar1a (40,879Da) were isolated from A. praelongus and A. rugosus venoms, respectively. P-EPTX-Ap1a and P-EPTX-Ar1a are comprised of three different subunits, alpha, beta1 and beta2. The two toxins displayed similar levels of PLA(2) activity which was almost solely attributed to the alpha subunit in both toxins. P-EPTX-Ap1a (20-100nM) and P-EPTX-Ar1a (20-100nM) caused inhibition of indirect twitches of the skeletal muscle preparation without affecting contractile responses to nicotinic receptor agonists. Interestingly, only the alpha subunit of both toxins (300nM) displayed neurotoxic activity. Inhibition of PLA(2) activity markedly reduced the effect of the toxins on muscle twitch height. These results confirm that P-EPTX-Ap1a and P-EPTX-Ar1a are pre-synaptic neurotoxins and represent the second and third such toxins to be isolated from death adder venom. The presence of pre-synaptic neurotoxins in Acanthophis sp. venoms indicates that treatment strategies for envenoming by these snakes needs to be reassessed given the likelihood of irreversible neurotoxicity. PMID:20488165

  9. Isolation and characterisation of P-EPTX-Ap1a and P-EPTX-Ar1a: pre-synaptic neurotoxins from the venom of the northern (Acanthophis praelongus) and Irian Jayan (Acanthophis rugosus) death adders.

    PubMed

    Chaisakul, Janeyuth; Konstantakopoulos, Nicki; Smith, A Ian; Hodgson, Wayne C

    2010-09-15

    The neurotoxicity observed following death adder envenoming has been thought to be solely due to the presence of potent post-synaptic neurotoxins. Clinically, these effects are often poorly reversed by death adder antivenom or anticholinesterase, particularly when patients present with established paralysis. This suggests that either the post-synaptic neurotoxins are irreversible/'pseudo' irreversible, or the venom contains pre-synaptic neurotoxins that do not respond to antivenom. To support the later hypothesis, a pre-synaptic neurotoxin (P-EPTX-Aa1a) has recently been isolated from the venom of Acanthophis antarcticus. We examined Acanthophis praelongus and Acanthophis rugosus venoms for the presence of pre-synaptic neurotoxins. P-EPTX-Ap1a (40,719Da) and P-EPTX-Ar1a (40,879Da) were isolated from A. praelongus and A. rugosus venoms, respectively. P-EPTX-Ap1a and P-EPTX-Ar1a are comprised of three different subunits, alpha, beta1 and beta2. The two toxins displayed similar levels of PLA(2) activity which was almost solely attributed to the alpha subunit in both toxins. P-EPTX-Ap1a (20-100nM) and P-EPTX-Ar1a (20-100nM) caused inhibition of indirect twitches of the skeletal muscle preparation without affecting contractile responses to nicotinic receptor agonists. Interestingly, only the alpha subunit of both toxins (300nM) displayed neurotoxic activity. Inhibition of PLA(2) activity markedly reduced the effect of the toxins on muscle twitch height. These results confirm that P-EPTX-Ap1a and P-EPTX-Ar1a are pre-synaptic neurotoxins and represent the second and third such toxins to be isolated from death adder venom. The presence of pre-synaptic neurotoxins in Acanthophis sp. venoms indicates that treatment strategies for envenoming by these snakes needs to be reassessed given the likelihood of irreversible neurotoxicity.

  10. Differential myotoxic and cytotoxic activities of pre-synaptic neurotoxins from Papuan taipan (Oxyuranus scutellatus) and Irian Jayan death adder (Acanthophis rugosus) venoms.

    PubMed

    Chaisakul, Janeyuth; Parkington, Helena C; Isbister, Geoffrey K; Konstantakopoulos, Nicki; Hodgson, Wayne C

    2013-05-01

    Pre-synaptic PLA(2) neurotoxins are important components of many Australasian elapid snake venoms. These toxins disrupt neurotransmitter release. Taipoxin, a pre-synaptic neurotoxin isolated from the venom of the coastal taipan (Oxyuranus scutellatus), causes necrosis and muscle degeneration. The present study examined the myotoxic and cytotoxic activities of venoms from the Papuan taipan (O. scutellatus) and Irian Jayan death adder (Acanthophis rugosus), and also tested their pre-synaptic neurotoxins: cannitoxin and P-EPTX-Ar1a. Based on size-exclusion chromatography analysis, cannitoxin represents 16% of O. scutellatus venom, while P-EPTX-Ar1a represents 6% of A. rugosus venom. In the chick biventer cervicis nerve-muscle preparation, A. rugosus venom displayed significantly higher myotoxic activity than O. scutellatus venom as indicated by inhibition of direct twitches, and an increase in baseline tension. Both cannitoxin and P-EPTX-Ar1a displayed marked myotoxic activity. A. rugosus venom (50-300 μg/ml) produced concentration-dependent inhibition of cell proliferation in a rat skeletal muscle cell line (L6), while 300 μg/ml of O. scutellatus venom was required to inhibit cell proliferation, following 24-hr incubation. P-EPTX-Ar1a had greater cytotoxicity than cannitoxin, inhibiting cell proliferation after 24-hr incubation in L6 cells. Lactate dehydrogenase levels were increased after 1-hr incubation with A. rugosus venom (100-250 μg/ml), O. scutellatus venom (200-250 μg/ml) and P-EPTX-Ar1a (1-2 μM), but not cannitoxin (1-2 μM), suggesting venoms/toxin generated cell necrosis. Thus, A. rugosus and O. scutellatus venoms possess different myotoxic and cytotoxic activities. The proportion of pre-synaptic neurotoxin in the venoms and PLA(2) activity of the whole venoms are unlikely to be responsible for these activities.

  11. Nowhere to Go but Up: Impacts of Climate Change on Demographics of a Short-Range Endemic (Crotalus willardi obscurus) in the Sky-Islands of Southwestern North America.

    PubMed

    Davis, Mark A; Douglas, Marlis R; Webb, Colleen T; Collyer, Michael L; Holycross, Andrew T; Painter, Charles W; Kamees, Larry K; Douglas, Michael E

    2015-01-01

    Biodiversity elements with narrow niches and restricted distributions (i.e., 'short range endemics,' SREs) are particularly vulnerable to climate change. The New Mexico Ridge-nosed Rattlesnake (Crotalus willardi obscurus, CWO), an SRE listed under the U.S. Endangered Species Act within three sky islands of southwestern North America, is constrained at low elevation by drought and at high elevation by wildfire. We combined long-term recapture and molecular data with demographic and niche modeling to gauge its climate-driven status, distribution, and projected longevity. The largest population (Animas) is numerically constricted (N = 151), with few breeding adults (Nb = 24) and an elevated inbreeding coefficient (ΔF = 0.77; 100 years). Mean home range (0.07 km2) is significantly smaller compared to other North American rattlesnakes, and movements are within, not among sky islands. Demographic values, when gauged against those displayed by other endangered/Red-Listed reptiles [e.g., Loggerhead Sea Turtle (Caretta caretta)], are either comparable or markedly lower. Survival rate differs significantly between genders (femaleAdder (Vipera berus), a conservation icon in southern Sweden. Genetic rescue, a management approach successfully employed in similar situations, is ill advised in this situation due to climate-driven habitat change in the sky islands. CWO is a rare organism in a unique environment, with a conserved niche and a predisposition towards extinction. It is a bellwether for the

  12. Nowhere to Go but Up: Impacts of Climate Change on Demographics of a Short-Range Endemic (Crotalus willardi obscurus) in the Sky-Islands of Southwestern North America.

    PubMed

    Davis, Mark A; Douglas, Marlis R; Webb, Colleen T; Collyer, Michael L; Holycross, Andrew T; Painter, Charles W; Kamees, Larry K; Douglas, Michael E

    2015-01-01

    Biodiversity elements with narrow niches and restricted distributions (i.e., 'short range endemics,' SREs) are particularly vulnerable to climate change. The New Mexico Ridge-nosed Rattlesnake (Crotalus willardi obscurus, CWO), an SRE listed under the U.S. Endangered Species Act within three sky islands of southwestern North America, is constrained at low elevation by drought and at high elevation by wildfire. We combined long-term recapture and molecular data with demographic and niche modeling to gauge its climate-driven status, distribution, and projected longevity. The largest population (Animas) is numerically constricted (N = 151), with few breeding adults (Nb = 24) and an elevated inbreeding coefficient (ΔF = 0.77; 100 years). Mean home range (0.07 km2) is significantly smaller compared to other North American rattlesnakes, and movements are within, not among sky islands. Demographic values, when gauged against those displayed by other endangered/Red-Listed reptiles [e.g., Loggerhead Sea Turtle (Caretta caretta)], are either comparable or markedly lower. Survival rate differs significantly between genders (femaleAdder (Vipera berus), a conservation icon in southern Sweden. Genetic rescue, a management approach successfully employed in similar situations, is ill advised in this situation due to climate-driven habitat change in the sky islands. CWO is a rare organism in a unique environment, with a conserved niche and a predisposition towards extinction. It is a bellwether for the

  13. Nowhere to Go but Up: Impacts of Climate Change on Demographics of a Short-Range Endemic (Crotalus willardi obscurus) in the Sky-Islands of Southwestern North America

    PubMed Central

    Davis, Mark A.; Douglas, Marlis R.; Webb, Colleen T.; Collyer, Michael L.; Holycross, Andrew T.; Painter, Charles W.; Kamees, Larry K.; Douglas, Michael E.

    2015-01-01

    Biodiversity elements with narrow niches and restricted distributions (i.e., ‘short range endemics,’ SREs) are particularly vulnerable to climate change. The New Mexico Ridge-nosed Rattlesnake (Crotalus willardi obscurus, CWO), an SRE listed under the U.S. Endangered Species Act within three sky islands of southwestern North America, is constrained at low elevation by drought and at high elevation by wildfire. We combined long-term recapture and molecular data with demographic and niche modeling to gauge its climate-driven status, distribution, and projected longevity. The largest population (Animas) is numerically constricted (N = 151), with few breeding adults (Nb = 24) and an elevated inbreeding coefficient (ΔF = 0.77; 100 years). Mean home range (0.07km2) is significantly smaller compared to other North American rattlesnakes, and movements are within, not among sky islands. Demographic values, when gauged against those displayed by other endangered/Red-Listed reptiles [e.g., Loggerhead Sea Turtle (Caretta caretta)], are either comparable or markedly lower. Survival rate differs significantly between genders (femaleAdder (Vipera berus), a conservation icon in southern Sweden. Genetic rescue, a management approach successfully employed in similar situations, is ill advised in this situation due to climate-driven habitat change in the sky islands. CWO is a rare organism in a unique environment, with a conserved niche and a predisposition towards extinction. It is a bellwether for the

  14. Venomous snakebites.

    PubMed

    Adukauskienė, Dalia; Varanauskienė, Eglė; Adukauskaitė, Agnė

    2011-01-01

    More than 5 million people are bitten by venomous snakes annually and more than 100,000 of them die. In Europe, one person dies due to envenomation every 3 years. There is only one venomous snake species in Lithuania--the common adder (Vipera berus)--which belongs to the Viperidae family; however, there are some exotic poisonous snakes in the zoos and private collections, such as those belonging to the Elapidae family (cobras, mambas, coral snakes, etc.) and the Crotalidae subfamily of the Viperidae family (pit vipers, such as rattlesnakes). Snake venom can be classified into hemotoxic, neurotoxic, necrotoxic, cardiotoxic, and nephrotoxic according to the different predominant effects depending on the family (i.e., venom of Crotalidae and Viperidae snakes is more hemotoxic and necrotoxic, whereas venom of Elapidae family is mainly neurotoxic). The intoxication degree is estimated according to the appearance of these symptoms: 1) no intoxication ("dry" bite); 2) mild intoxication (local edema and pain); 3) moderate intoxication (pain, edema spreading out of the bite zone, and systemic signs); 4) severe intoxication (shock, severe coagulopathy, and massive edemas). This topic is relevant because people tend to make major mistakes providing first aid (e.g., mouth suction, wound incision, and application of ice or heat). Therefore, this article presents the essential tips on how first aid should be performed properly according to the "Guidelines for the Management of Snake-Bites" by the World Health Organization (2010). Firstly, the victim should be reassured. Rings or other things must be removed preventing constriction of the swelling limb. Airway/breathing must be maintained. The bitten limb should be immobilized and kept below heart level to prevent venom absorption and systemic spread. Usage of pressure bandage is controversial since people usually apply it improperly. Incision, mouth suction, or excision should not be performed; neither a tourniquet nor ice or

  15. [The viper--Finland's only poisonous snake].

    PubMed

    Vuori, Arno

    2011-01-01

    The viper (Vipera berus) is the most common poisonous snake in Europe, and the only one in Finland. In viper bites, highly varying amounts of venom end up into the victim, whereby prediction of the progression of symptoms of poisoning is very difficult. A severe clinical picture must always be anticipated. The size of the victim has also an effect on the outcome. Adequate monitoring and when necessary, massive fluid therapy are essential in the treatment. Due to possible kidney damage, anti-inflammatory drugs are not recommended. Severe or rapidly progressing symptoms require the use of an antidote.

  16. AWAIC: A WISE Astronomical Image Co-adder

    NASA Astrophysics Data System (ADS)

    Masci, Frank J.; Fowler, J. W.; Cutri, R. M.

    2009-05-01

    The Wide-field Infrared Survey Explorer (WISE) is a NASA Midex mission launching in late 2009 that will survey the entire sky at 3.3, 4.7, 12, and 23 microns with sensitivities up to three orders of magnitude beyond those achieved with IRAS. One of its products is a digital Image Atlas that will combine survey exposures within predefined tiles on the sky. To support this, we have developed a generic frame co-addition tool, AWAIC, for execution in the automated pipeline. We review AWAIC's algorithms, functions and products. The software includes preparatory steps such as frame background matching and outlier detection. Frame co-addition is based on using the detector's Point Response Function (PRF) as an interpolation kernel. This kernel reduces the impact of prior-masked pixels; enables the creation of an optimal matched filtered product for point source detection; and most important, it allows for optional resolution enhancement (HiRes) to yield a "model" of the sky that is consistent with the measurements within their uncertainties. This is accomplished through a Richardson-Lucy like procedure, extended to include non-isoplanatic PRFs, prior noise weighting, variance estimation, and ringing suppression. HiRes is not in the WISE automated processing plan. Ancillary products include images of uncertainties, depth-of-coverage, and outlier locations. AWAIC supports the FITS standard with all common projections and coordinate systems. It will be made portable in the near future.

  17. AWAIC: A WISE Astronomical Image Co-adder

    NASA Astrophysics Data System (ADS)

    Masci, Franck J.; Fowler, J.; Cutri, R.; Science Data Center, WISE

    2009-01-01

    The Wide-field Infrared Survey Explorer (WISE) is a NASA Midex mission launching in late 2009 that will survey the entire sky at 3.3, 4.7, 12, and 23 microns with sensitivities up to three orders of magnitude beyond those achieved with IRAS. One of its products is a digital Image Atlas that will combine survey exposures within predefined tiles on the sky. To support this, we have developed a generic frame co-addition tool, AWAIC, for execution in the automated pipeline. Here we describe AWAIC's algorithms, functionality, and products. The software includes preparatory steps such as frame background matching and outlier detection. Frame co-addition is based on using the detector's Point Response Function (PRF) as an interpolation kernel. This kernel reduces the impact of prior-masked pixels; enables the creation of an optimal matched filtered product for point source detection; and most important, it allows for resolution enhancement (HiRes) to yield a "model" of the sky that is consistent with the observations within their uncertainties. This is accomplished through a Richardson-Lucy like procedure, extended to include non-isoplanatic PRFs, prior noise weighting, variance estimation, and ringing-artifact suppression. HiRes is not in the WISE automated processing plan. Ancillary products include images of uncertainties, depth-of-coverage, and outlier locations. AWAIC supports the FITS standard with all common projections and coordinate systems, and will be made portable in the near future.

  18. Vibrational computing: simulation of a full adder by optimal control.

    PubMed

    Bomble, L; Lauvergnat, D; Remacle, F; Desouter-Lecomte, M

    2008-02-14

    Within the context of vibrational molecular quantum computing, we investigate the implementation of a full addition of two binary digits and a carry that provides the sum and the carry out. Four qubits are necessary and they are encoded into four different normal vibrational modes of a molecule. We choose the bromoacetyl chloride molecule because it possesses four bright infrared active modes. The ground and first excited states of each mode form the one-qubit computational basis set. Two approaches are proposed for the realization of the full addition. In the first one, we optimize a pulse that implements directly the entire addition by a single unitary transformation. In the second one, we decompose the full addition in elementary quantum gates, following a scheme proposed by Vedral et al. [Phys. Rev. A 54, 147 (1996)]. Four elementary quantum gates are necessary, two two-qubit CNOT gates (controlled NOT) and two three-qubit TOFFOLI gates (controlled-controlled NOT). All the logic operations consist in one-qubit flip. The logic implementation is therefore quasiclassical and the readout is based on a population analysis of the vibrational modes that does not take the phases into account. The fields are optimized by the multitarget extension of the optimal control theory involving all the transformations among the 2(4) qubit states. A single cycle of addition without considering the preparation or the measure or copy of the result can be carried out in a very competitive time, on a picosecond time scale. PMID:18282031

  19. MULTIPLE INPUT BINARY ADDER EMPLOYING MAGNETIC DRUM DIGITAL COMPUTING APPARATUS

    DOEpatents

    Cooke-Yarborough, E.H.

    1960-12-01

    A digital computing apparatus is described for adding a plurality of multi-digit binary numbers. The apparatus comprises a rotating magnetic drum, a recording head, first and second reading heads disposed adjacent to the first and second recording tracks, and a series of timing signals recorded on the first track. A series of N groups of digit-representing signals is delivered to the recording head at time intervals corresponding to the timing signals, each group consisting of digits of the same significance in the numbers, and the signal series is recorded on the second track of the drum in synchronism with the timing signals on the first track. The multistage registers are stepped cyclically through all positions, and each of the multistage registers is coupled to the control lead of a separate gate circuit to open the corresponding gate at only one selected position in each cycle. One of the gates has its input coupled to the bistable element to receive the sum digit, and the output lead of this gate is coupled to the recording device. The inputs of the other gates receive the digits to be added from the second reading head, and the outputs of these gates are coupled to the adding register. A phase-setting pulse source is connected to each of the multistage registers individually to step the multistage registers to different initial positions in the cycle, and the phase-setting pulse source is actuated each N time interval to shift a sum digit to the bistable element, where the multistage register coupled to bistable element is operated by the phase- setting pulse source to that position in its cycle N steps before opening the first gate, so that this gate opens in synchronism with each of the shifts to pass the sum digits to the recording head.

  20. Cytotoxic Effect of Iranian Vipera lebetina Snake Venom on HUVEC Cells

    PubMed Central

    Kakanj, Maryam; Ghazi-Khansari, Mahmoud; Zare Mirakabadi, Abbas; Daraei, Bahram; Vatanpour, Hossein

    2015-01-01

    Objective: Envenomation by heamotoxic snakes constituted a critical health occurrence in the world. Bleeding is the most sever consequence following snake bite with viperid and crothalid snakes. It is believed that the degradation of vascular membrane caused hemorrhage; in contrast, some suggested that direct cytotoxicity has role in endothelial cell disturbances. This study was carried out to evaluate the direct toxicity effect of V. lebetina crude venom on Human Umbilical Vein Endothelial Cells (HUVECs). Methods: The effect of V. lebetina snake venom on HUVECs growth inhibition was determined by MTT assay and neutral red uptake assay. The integrity of cell membrane through LDH release was measured with the Cytotoxicity Detection Kit. Morphological changes of endothelial cells were also evaluated using a phase contrast microscope. Result: In MTT assay, crude venom showed a cytotoxic effect on endothelial cells which was confirmed by the effect observed with neutral red assay. Also, crude venom caused changes in the integrity of cell membrane by LDH release. The morphological alterations enhanced in high concentration results in total cells number reduced. Conclusion: V. lebetina venom showed potential direct cytotoxic effects on human endothelial cells in a manner of concentration- dependent inhibition. PMID:26185512

  1. Varespladib (LY315920) Appears to Be a Potent, Broad-Spectrum, Inhibitor of Snake Venom Phospholipase A2 and a Possible Pre-Referral Treatment for Envenomation

    PubMed Central

    Lewin, Matthew; Samuel, Stephen; Merkel, Janie; Bickler, Philip

    2016-01-01

    Snakebite remains a neglected medical problem of the developing world with up to 125,000 deaths each year despite more than a century of calls to improve snakebite prevention and care. An estimated 75% of fatalities from snakebite occur outside the hospital setting. Because phospholipase A2 (PLA2) activity is an important component of venom toxicity, we sought candidate PLA2 inhibitors by directly testing drugs. Surprisingly, varespladib and its orally bioavailable prodrug, methyl-varespladib showed high-level secretory PLA2 (sPLA2) inhibition at nanomolar and picomolar concentrations against 28 medically important snake venoms from six continents. In vivo proof-of-concept studies with varespladib had striking survival benefit against lethal doses of Micrurus fulvius and Vipera berus venom, and suppressed venom-induced sPLA2 activity in rats challenged with 100% lethal doses of M. fulvius venom. Rapid development and deployment of a broad-spectrum PLA2 inhibitor alone or in combination with other small molecule inhibitors of snake toxins (e.g., metalloproteases) could fill the critical therapeutic gap spanning pre-referral and hospital setting. Lower barriers for clinical testing of safety tested, repurposed small molecule therapeutics are a potentially economical and effective path forward to fill the pre-referral gap in the setting of snakebite. PMID:27571102

  2. Varespladib (LY315920) Appears to Be a Potent, Broad-Spectrum, Inhibitor of Snake Venom Phospholipase A2 and a Possible Pre-Referral Treatment for Envenomation.

    PubMed

    Lewin, Matthew; Samuel, Stephen; Merkel, Janie; Bickler, Philip

    2016-01-01

    Snakebite remains a neglected medical problem of the developing world with up to 125,000 deaths each year despite more than a century of calls to improve snakebite prevention and care. An estimated 75% of fatalities from snakebite occur outside the hospital setting. Because phospholipase A2 (PLA2) activity is an important component of venom toxicity, we sought candidate PLA2 inhibitors by directly testing drugs. Surprisingly, varespladib and its orally bioavailable prodrug, methyl-varespladib showed high-level secretory PLA2 (sPLA2) inhibition at nanomolar and picomolar concentrations against 28 medically important snake venoms from six continents. In vivo proof-of-concept studies with varespladib had striking survival benefit against lethal doses of Micrurus fulvius and Vipera berus venom, and suppressed venom-induced sPLA2 activity in rats challenged with 100% lethal doses of M. fulvius venom. Rapid development and deployment of a broad-spectrum PLA2 inhibitor alone or in combination with other small molecule inhibitors of snake toxins (e.g., metalloproteases) could fill the critical therapeutic gap spanning pre-referral and hospital setting. Lower barriers for clinical testing of safety tested, repurposed small molecule therapeutics are a potentially economical and effective path forward to fill the pre-referral gap in the setting of snakebite. PMID:27571102

  3. RADLAC II/SMILE performance with a magnetically insulated voltage adder

    SciTech Connect

    Shope, S.L.; Mazarakis, M.G.; Frost, C.A.; Crist, C.E.; Poukey, J.W.; Prestwich, K.R.; Turman, B.N. ); Struve, K.; Welch, D. )

    1991-01-01

    A 12.5-m long Self Magnetically Insulated Transmission LinE (SMILE) that sums the voltages of 8, 2-MV pulse forming lines was installed in the RADLAC-II linear induction accelerator. The magnetic insulation criteria was calculated using parapotential flow theory and found to agree with MAGIC simulations. High quality annular beams with {beta}{perpendicular} {le} 0.1 and a radius r{sub b} < 2 cm were measured for currents of 50--100-kA extracted from a magnetic immersed foilless diode. These parameters were achieved with 11 to 15-MV accelerating voltages and 6 to 16-kG diode magnetic field. The experimental results exceeded our design expectations and are in good agreement with code simulations. 6 refs., 6 figs., 1 tab.

  4. A novel nonhemorragic protease from the African puff adder (Bitis arietans) venom.

    PubMed

    Nok, A J

    2001-01-01

    A nonhemorrhagic proteinase B-20 from the venom of Bitis arietans has been purified to apparent electrophoretic homogeneity by chromatography on Sephadex G-100, Q-Sepharose, and CM-cellulose. It has a molecular weight of 20 k Da as determined by size exclusion chromatography on Sephadex G-100 and migrated as a single 20-k Da band on SDS polyacrylamide. It has an optimum pH of 6-8 and is inactive at pH 4.0. EDTA and 1,10-phenanthroline strongly inhibited the enzyme suggesting it is a metalloenzyme. Also it is inhibited by antipain but is unaffected by trasylol, antitrypsin, and pepsptatin. Colombin, an identified active component of Aristolochia albida used in the treatment of snake poisoning, did not inhibit the protease activity. It lost over 90% of its activity in the presence of 0.5 microM Hg(2+) but the inhibition was completely blocked in the presence of 10 microM mercaptoethanol implicating sulfhydryl groups in the catalytic entity of the protein. The activity was also inhibited competitively by glutathione and cysteine with inhibition binding constants K(i) of 240 and 40 microM, respectively. The enzyme is unaffected by several divalent cations but activated by 1 mM Fe(3+). It had a prolyl endopeptidase and thermolysin-like activity. The enzyme displayed a fast acting alpha-fibrinolytic and delayed gamma-fibrinolytic activity when tested on human fibrinogen. The relevance of these findings is discussed. PMID:11673850

  5. Pencil-like mm-size electron beams produced with linear inductive voltage adders (LIVA)

    SciTech Connect

    Mazarakis, M.G.; Poukey, J.W.; Rovang, D.C.

    1996-09-01

    This paper presents design, analysis, and first results of the high brightness electron beam experiments currently under investigation at Sandia. Anticipated beam parameters are: energy 12 MeV, current 35-40 kA, rms radius 0.5 mm, pulse duration 40 ns FWHM. The accelerator is SABRE, a pulsed LIVA modified to higher impedance, and the electron source is a magnetically immersed foilless electron diode. 20 to 30 Tesla solenoidal magnets are required to insulate the diode and contain the beam to its extremely small sized (1 mm) envelope. These experiments are designed to push the technology to produce the highest possible electron current in a submillimeter radius beam. Design, numercial simulations, and first experimental results are presented.

  6. Costs of venom production in the common death adder (Acanthophis antarcticus).

    PubMed

    Pintor, Anna F V; Krockenberger, Andrew K; Seymour, Jamie E

    2010-11-01

    The utilization of venom in predatory and defensive contexts is associated with benefits regarding minimization of energetic expenditure on hunting, maximization of success in prey acquisition and avoidance of injury from dangerous prey and aggressors. Multiple characteristics suggest that venom is quite expensive to produce, thereby creating a tradeoff between advantages and disadvantages associated with its possession. The metabolic costs of venom production have rarely been studied and no information on the detailed metabolic processes during venom replenishment exists. Where costs of venom production have been studied they are often not in context with other components of the energy budget of the study organism. Using flow-through respirometry, we examined changes in metabolic rate in the Australian elapid Acanthophis antarcticus after venom expenditure and feeding as well as during preparation for shedding to establish a comparison of the magnitude of energetic expenditure during venom replenishment and other common physiological processes. We also defined the temporal pattern of metabolic processes during venom replenishment at a higher resolution than has previously been attempted in snakes. Our results suggest that total costs of venom replenishment are relatively small when compared to costs of digestion and shedding. We conclude that, in spite of the manifold factors suggesting a high cost of venom in snakes, its production is less energetically costly than often assumed. Until further research can clarify the reasons for this more caution should therefore be applied when assuming that costs of venom production exert strong selection pressures on the ecology, behavior and evolution of venomous taxa. PMID:20659494

  7. Multi-input and binary reproducible, high bandwidth floating point adder in a collective network

    DOEpatents

    Chen, Dong; Eisley, Noel A; Heidelberger, Philip; Steinmacher-Burow, Burkhard

    2015-03-10

    To add floating point numbers in a parallel computing system, a collective logic device receives the floating point numbers from computing nodes. The collective logic devices converts the floating point numbers to integer numbers. The collective logic device adds the integer numbers and generating a summation of the integer numbers. The collective logic device converts the summation to a floating point number. The collective logic device performs the receiving, the converting the floating point numbers, the adding, the generating and the converting the summation in one pass. One pass indicates that the computing nodes send inputs only once to the collective logic device and receive outputs only once from the collective logic device.

  8. Inhibition of Nicotinic Acetylcholine Receptors, a Novel Facet in the Pleiotropic Activities of Snake Venom Phospholipases A2

    PubMed Central

    Vulfius, Catherine A.; Kasheverov, Igor E.; Starkov, Vladislav G.; Osipov, Alexey V.; Andreeva, Tatyana V.; Filkin, Sergey Yu.; Gorbacheva, Elena V.; Astashev, Maxim E.; Tsetlin, Victor I.; Utkin, Yuri N.

    2014-01-01

    Phospholipases A2 represent the most abundant family of snake venom proteins. They manifest an array of biological activities, which is constantly expanding. We have recently shown that a protein bitanarin, isolated from the venom of the puff adder Bitis arietans and possessing high phospholipolytic activity, interacts with different types of nicotinic acetylcholine receptors and with the acetylcholine-binding protein. To check if this property is characteristic to all venom phospholipases A2, we have studied the capability of these enzymes from other snakes to block the responses of Lymnaea stagnalis neurons to acetylcholine or cytisine and to inhibit α-bungarotoxin binding to nicotinic acetylcholine receptors and acetylcholine-binding proteins. Here we present the evidence that phospholipases A2 from venoms of vipers Vipera ursinii and V. nikolskii, cobra Naja kaouthia, and krait Bungarus fasciatus from different snake families suppress the acetylcholine- or cytisine-elicited currents in L. stagnalis neurons and compete with α-bungarotoxin for binding to muscle- and neuronal α7-types of nicotinic acetylcholine receptor, as well as to acetylcholine-binding proteins. As the phospholipase A2 content in venoms is quite high, under some conditions the activity found may contribute to the deleterious venom effects. The results obtained suggest that the ability to interact with nicotinic acetylcholine receptors may be a general property of snake venom phospholipases A2, which add a new target to the numerous activities of these enzymes. PMID:25522251

  9. Twentieth century toxinology and antivenom development in Australia.

    PubMed

    Winkel, Kenneth D; Mirtschin, Peter; Pearn, John

    2006-12-01

    It was not until the last decade of the 19th century that an experimental approach (led by Bancroft in Queensland and Martin in Sydney and Melbourne) brought a higher plane of scientific objectivity to usher in the modern era of Australian toxinology. This Australia era, 1895-1905, coincided with and in some respects was the result of the new knowledge emerging from Europe and the Americas of the therapeutic effects of antitoxins. The subsequent systematic study of Australian venoms and toxins through to the 1930s and beyond, by Tidswell, Fairley, Ross, Kellaway and Cleland, set the foundation for Australia's leading reputation in venom research. As elsewhere, this development was to revolutionise the medical management of those victims who in the past had died in Australia from our venomous and toxic fauna. Morgan, Graydon, Weiner, Lane and Baxter at the Commonwealth Serum Laboratories emphasised the importance of cooperation between those expert at catching and milking the venomous creatures and those developing the antivenoms. Commercial antivenom manufacture began in Australia in 1930 with the tiger snake antivenom. This was followed by other antivenoms for the other important species (1955: taipan; 1956: brown snake; 1958: death adder; 1959: Papuan black snake; 1961: sea snake; 1962: polyvalent) including the first marine antivenoms in the world (1956: stonefish antivenom; 1970: box jellyfish) culminating, in 1980, with the release of the funnel web spider antivenom. More recent activity has focused on veterinary antivenoms and production of new generation human antivenoms for export (CroFab and ViperaTAB). This paper reviews some of the milestones of Australian toxinology, and antivenom development in particular, during the 20th century.

  10. Simultaneous all-optical half-adder, half-subtracter, comparator, and decoder based on nonlinear effects harnessing in highly nonlinear fibers

    NASA Astrophysics Data System (ADS)

    Singh, Karamdeep; Kaur, Gurmeet; Singh, Maninder Lal

    2016-07-01

    A multifunctional combinational logic module capable of performing several signal manipulation tasks all-optically, such as half-addition/subtraction, single-bit comparison, and 2-to-4 decoding simultaneously is proposed. Several logic functions (A+B¯, A.B, A¯.B, A.B¯, A⊕B, and A⊙B) between two input signals A and B are implemented by harnessing a number of nonlinear effects, such as cross-phase modulation (XPM), cross-gain modulation (XGM), and four-wave mixing (FWM) inside only two highly nonlinear fibers (HNLF) arranged in a parallel structure. The NOR gate (A+B¯) is realized by the means of XPM effect in the first HNLF, whereas, A‾.B, A.B¯, and A.B logics have relied on utilization of XGM and FWM processes, respectively, in parametric medium made up of the second HNLF of parallel arrangement. The remaining A⊕B and A⊙B logics required for successful implementation of the proposed simultaneous scheme are attained by temporally combining previously achieved (A‾.B and A.B‾) and (A.B and A+B‾) logics. Quality-factor ≥7.4 and extinction ratio ≥12.30 dB have been achieved at repetition rates of 100 Gbps for all logic functions (A+B‾, A.B, A¯.B, A.B¯, A⊕B, and A⊙B), suggesting successful simultaneous implementation.

  11. Linear induction accelerator and pulse forming networks therefor

    DOEpatents

    Buttram, Malcolm T.; Ginn, Jerry W.

    1989-01-01

    A linear induction accelerator includes a plurality of adder cavities arranged in a series and provided in a structure which is evacuated so that a vacuum inductance is provided between each adder cavity and the structure. An energy storage system for the adder cavities includes a pulsed current source and a respective plurality of bipolar converting networks connected thereto. The bipolar high-voltage, high-repetition-rate square pulse train sets and resets the cavities.

  12. Linear induction accelerator

    DOEpatents

    Buttram, M.T.; Ginn, J.W.

    1988-06-21

    A linear induction accelerator includes a plurality of adder cavities arranged in a series and provided in a structure which is evacuated so that a vacuum inductance is provided between each adder cavity and the structure. An energy storage system for the adder cavities includes a pulsed current source and a respective plurality of bipolar converting networks connected thereto. The bipolar high-voltage, high-repetition-rate square pulse train sets and resets the cavities. 4 figs.

  13. Pipeline active filter utilizing a booth type multiplier

    NASA Technical Reports Server (NTRS)

    Nathan, Robert (Inventor)

    1987-01-01

    Multiplier units of the modified Booth decoder and carry-save adder/full adder combination are used to implement a pipeline active filter wherein pixel data is processed sequentially, and each pixel need only be accessed once and multiplied by a predetermined number of weights simultaneously, one multiplier unit for each weight. Each multiplier unit uses only one row of carry-save adders, and the results are shifted to less significant multiplier positions and one row of full adders to add the carry to the sum in order to provide the correct binary number for the product Wp. The full adder is also used to add this product Wp to the sum of products .SIGMA.Wp from preceding multiply units. If m.times.m multiplier units are pipelined, the system would be capable of processing a kernel array of m.times.m weighting factors.

  14. Exploiting Symmetry for Quantum Error Suppression

    NASA Astrophysics Data System (ADS)

    Nam, Yunseong; Blümel, Reinhold

    2016-05-01

    In light of recent experimental progress in quantum computing, the time is ripe to discuss quantum computer hardware optimization. Taking the digital/analog hybrid nature of quantum computers into account, choosing a proper processor architecture for a given quantum algorithm becomes crucial in making quantum computing a practical reality. As a first step in this direction, we investigate the robustness of quantum adders with respect to naturally occurring hardware defects and errors. In particular, we compare the robustness of the ripple-carry adder to that of the quantum Fourier adder. We show that, surprisingly, when used in Shor's algorithm, the quantum Fourier adder may well be more robust than the ripple-carry adder. We present a noise suppression scheme, called symmetric noise, applicable to the quantum Fourier architecture, that, measured in terms of fidelity, results in an order-of-magnitude performance boost.

  15. MULTI-CHANNEL ELECTRIC PULSE HEIGHT ANALYZER

    DOEpatents

    Gallagher, J.D. et al.

    1960-11-22

    An apparatus is given for converting binary information into coded decimal form comprising means, in combination with a binary adder, a live memory and a source of bigit pulses, for synchronizing the bigit pulses and the adder output pulses; a source of digit pulses synchronized with every fourth bigit pulse; means for generating a conversion pulse in response to the time coincidence of the adder output pulse and a digit pulse: means having a delay equal to two bigit pulse periods coupling the adder output with the memory; means for promptly impressing said conversion pulse on the input of said memory: and means having a delay equal to one bigit pulse period for again impressing the conversion pulse on the input of the memory whereby a fourth bigit adder pulse results in the insertion into the memory of second, third and fourth bigits.

  16. The effects of environment and physiological cyclicity on the immune system of Viperinae.

    PubMed

    Kobolkuti, Lorand; Cadar, Daniel; Czirjak, Gabor; Niculae, Mihaela; Kiss, Timea; Sandru, Carmen; Spinu, Marina

    2012-01-01

    One of the important aspects of species' survival is connected with global climate changes, which also conditions the epidemiology of infectious diseases. Poikilotherms are exposed, as other species, to climatic influence, especially due to their physiological peculiarities such as important stages of their life cycle: hibernation, shedding, and active phase. The immune system serves as an accurate indicator of the health status and stress levels in these species. This study aimed to monitor the changes of innate (leukocyte subpopulations and total immune globulins) and adaptive immunity (in vitro leukocyte blast transformation) of two viper species, V. berus berus and V. ammodytes ammodytes, endemic in Europe and spread in different regions of Romania during their three major life cycles, hibernation, shedding, and active phase. The results indicated that seasonal variance and cycle rather than species and regional distribution influence the functionality of the immune system.

  17. The effects of environment and physiological cyclicity on the immune system of Viperinae.

    PubMed

    Kobolkuti, Lorand; Cadar, Daniel; Czirjak, Gabor; Niculae, Mihaela; Kiss, Timea; Sandru, Carmen; Spinu, Marina

    2012-01-01

    One of the important aspects of species' survival is connected with global climate changes, which also conditions the epidemiology of infectious diseases. Poikilotherms are exposed, as other species, to climatic influence, especially due to their physiological peculiarities such as important stages of their life cycle: hibernation, shedding, and active phase. The immune system serves as an accurate indicator of the health status and stress levels in these species. This study aimed to monitor the changes of innate (leukocyte subpopulations and total immune globulins) and adaptive immunity (in vitro leukocyte blast transformation) of two viper species, V. berus berus and V. ammodytes ammodytes, endemic in Europe and spread in different regions of Romania during their three major life cycles, hibernation, shedding, and active phase. The results indicated that seasonal variance and cycle rather than species and regional distribution influence the functionality of the immune system. PMID:22547989

  18. Increase in the Array Television Camera Sensitivity

    NASA Astrophysics Data System (ADS)

    Shakhrukhanov, O. S.

    A simple adder circuit for successive television frames that enables to considerably increase the sensitivity of such radiation detectors is suggested by the example of array television camera QN902K.

  19. A Path to Discovery

    ERIC Educational Resources Information Center

    Stegemoller, William; Stegemoller, Rebecca

    2004-01-01

    The path taken and the turns made as a turtle traces a polygon are examined to discover an important theorem in geometry. A unique tool, the Angle Adder, is implemented in the investigation. (Contains 9 figures.)

  20. Raman spectroscopic studies of the skins of the Sahara sand viper, the carpet python and the American black rat snake

    NASA Astrophysics Data System (ADS)

    Edwards, H. G. M.; Farwell, D. W.; Williams, A. C.; Barry, B. W.

    1993-07-01

    Vibrational Raman spectra of the skins of the snakes Cerastes vipera (Sahara sand viper) and Morelia argus (carpet python) have been recorded for the first time using visible and IR laser excitation. Full vibrational assignments are proposed and comparisons made with vibrational Raman spectra of the snake Elaphe obsoleta (American black rat snake); such studies may be important in correlating the permeabilities of human and snake skins to drugs and contaminants.

  1. Approach to the epidemiology of venomous bites in Spain.

    PubMed

    Saz-Parkinson, Zuleika; del Pino Luengo, Miguel; López-Cuadrado, Teresa; Andújar, Dionisio; Carmona-Alférez, Rocío; Flores, Ricardo Martín; Amate, José María

    2012-09-15

    This review presents a geographic distribution of the three autochthonous venomous snake species, which are the only viperids present in Spain, among the Iberian fauna: Vipera aspid; Vipera seoianei and Vipera latasti. This is followed by a detailed descriptive analysis of hospital care provided to patients admitted into hospital due to venomous bites, in the period from 1997 to 2009, using the data from the Spanish hospital discharge registry database. This analysis reveals that in Spain, during this period, 1649 cases were recorded, which means that hospital care was required for more than one hundred cases per year, of which nearly 1% of the cases resulted in death. Cases were recorded in all the Autonomous communities, but more than half (54, 14%) were concentrated in the following four regions: Cataluña, Castilla and León, Galicia and Andalucía. It is notable that this concentration of cases is not associated only with the population demographics of the community, but is also the result of the concurrence of very diverse factors of exposure including: habitat of venomous fauna, volume of rural population, farming activities, and practice of outdoor leisure activities. We also carried out a gross economic calculation for the use of hospital resources by each snakebite case requiring hospital care in Spain, which provided us with an approximate figure of 2000€ per case. PMID:22484223

  2. Approach to the epidemiology of venomous bites in Spain.

    PubMed

    Saz-Parkinson, Zuleika; del Pino Luengo, Miguel; López-Cuadrado, Teresa; Andújar, Dionisio; Carmona-Alférez, Rocío; Flores, Ricardo Martín; Amate, José María

    2012-09-15

    This review presents a geographic distribution of the three autochthonous venomous snake species, which are the only viperids present in Spain, among the Iberian fauna: Vipera aspid; Vipera seoianei and Vipera latasti. This is followed by a detailed descriptive analysis of hospital care provided to patients admitted into hospital due to venomous bites, in the period from 1997 to 2009, using the data from the Spanish hospital discharge registry database. This analysis reveals that in Spain, during this period, 1649 cases were recorded, which means that hospital care was required for more than one hundred cases per year, of which nearly 1% of the cases resulted in death. Cases were recorded in all the Autonomous communities, but more than half (54, 14%) were concentrated in the following four regions: Cataluña, Castilla and León, Galicia and Andalucía. It is notable that this concentration of cases is not associated only with the population demographics of the community, but is also the result of the concurrence of very diverse factors of exposure including: habitat of venomous fauna, volume of rural population, farming activities, and practice of outdoor leisure activities. We also carried out a gross economic calculation for the use of hospital resources by each snakebite case requiring hospital care in Spain, which provided us with an approximate figure of 2000€ per case.

  3. Effects of seasonal variation in prey abundance on field metabolism, water flux, and activity of a tropical ambush foraging snake.

    PubMed

    Christian, Keith; Webb, Jonathan K; Schultz, Timothy; Green, Brian

    2007-01-01

    The responses of animals to seasonal food shortages can have important consequences for population dynamics and the structure and function of food webs. We investigated how an ambush foraging snake, the northern death adder Acanthophis praelongus, responds to seasonal fluctuations in prey availability in its tropical environment. In the dry season, field metabolic rates and water flux, as measured by doubly labeled water, were significantly lower than in the wet season. Unlike some other reptiles of the wet-dry tropics, death adders showed no seasonal difference in their resting metabolism. About 94% of the decrease in energy expended in the dry season was due to a decrease in activity and digestion, with lower body temperatures accounting for the remainder. In the dry season, death adders were less active and moved shorter distances between foraging sites than in the wet season. Analysis of energy expenditure suggested that adders fed no more than every 2-3 wk in the dry season but fed more frequently during the wet season. Unlike many lizards that cease feeding during the dry season, death adders remain active and attempt to maximize their energy intake year-round.

  4. FPGA-specific decimal sign-magnitude addition and subtraction

    NASA Astrophysics Data System (ADS)

    Vázquez, Martín; Todorovich, Elías

    2016-07-01

    The interest in sign-magnitude (SM) representation in decimal numbers lies in the IEEE 754-2008 standard, where the significand in floating-point numbers is coded as SM. However, software implementations do not meet performance constraints in some applications and more development is required in programmable logic, a key technology for hardware acceleration. Thus, in this work, two strategies for SM decimal adder/subtractors are studied and six new Field Programmable Gate Array (FPGA)-specific circuits are derived from these strategies. The first strategy is based on ten's complement (C10) adder/subtractors and the second one is based on parallel computation of an unsigned adder and an unsigned subtractor. Four of these alternative circuits are useful for at least one area-time-trade-off and specific operand size. For example, the fastest SM adder/subtractor for operand sizes of 7 and 16 decimal digits is based on the second proposed strategy with delays of 3.43 and 4.33 ns, respectively, but the fastest circuit for 34-digit operands is one of the three specific implementations based on C10 adder/subtractors with a delay of 4.65 ns.

  5. ARC length control for plasma welding

    NASA Technical Reports Server (NTRS)

    Iceland, William F. (Inventor)

    1988-01-01

    A control system to be used with a plasma arc welding apparatus is disclosed. The plasma arc welding apparatus includes a plasma arc power supply, a contactor, and an electrode assembly for moving the electrode relative to a work piece. The electrode assembly is raised or lowered by a drive motor. The present apparatus includes a plasma arc adapter connected across the power supply to measure the voltage across the plasma arc. The plasma arc adapter forms a dc output signal input to a differential amplifier. A second input is defined by an adjustable resistor connected to a dc voltage supply to permit operator control. The differential amplifier forms an output difference signal provided to an adder circuit. The adder circuit then connects with a power amplifier which forms the driving signal for the motor. In addition, the motor connects to a tachometor which forms a feedback signal delivered to the adder to provide damping, therby avoiding servo loop overshoot.

  6. DOIND: a technique for leakage reduction in nanoscale domino logic circuits

    NASA Astrophysics Data System (ADS)

    Prasad Shah, Ambika; Neema, Vaibhav; Daulatabad, Shreeniwas

    2016-05-01

    A novel DOIND logic approach is proposed for domino logic, which reduces the leakage current with a minimum delay penalty. Simulation is performed at 70 nm technology node with supply voltage 1V for domino logic and DOIND logic based AND, OR, XOR and Half Adder circuits using the tanner EDA tool. Simulation results show that the proposed DOIND approach decreases the average leakage current by 68.83%, 66.6%, 77.86% and 74.34% for 2 input AND, OR, XOR and Half Adder respectively. The proposed approach also has 47.76% improvement in PDAP for the buffer circuit as compared to domino logic.

  7. Area-efficient nonvolatile carry chain based on pass-transistor/atom-switch hybrid logic

    NASA Astrophysics Data System (ADS)

    Bai, Xu; Tsuji, Yukihide; Sakamoto, Toshitsugu; Morioka, Ayuka; Miyamura, Makoto; Tada, Munehiro; Banno, Naoki; Okamoto, Koichiro; Iguchi, Noriyuki; Hada, Hiromitsu

    2016-04-01

    For the first time, an area-efficient nonvolatile carry chain combining look-up tables and a pass-transistor-logic-based adder is newly developed using complementary atom switches without additional CMOS circuits. A proposed tristate switch composed of three pairs of complementary atom switches selects one of “0”, “1”, and the “carry_in” signal as the input of a common multiplexer for both a look-up table and an adder. The developed nonvolatile carry chain achieves the reductions of 20% area, 17% delay, and 17% power consumption, respectively, in comparison with a conventional nonvolatile carry chain using dedicated CMOS gates.

  8. Integrated-Circuit Active Digital Filter

    NASA Technical Reports Server (NTRS)

    Nathan, R.

    1986-01-01

    Pipeline architecture with parallel multipliers and adders speeds calculation of weighted sums. Picture-element values and partial sums flow through delay-adder modules. After each cycle or time unit of calculation, each value in filter moves one position right. Digital integrated-circuit chips with pipeline architecture rapidly move 35 X 35 two-dimensional convolutions. Need for such circuits in image enhancement, data filtering, correlation, pattern extraction, and synthetic-aperture-radar image processing: all require repeated calculations of weighted sums of values from images or two-dimensional arrays of data.

  9. Chemical implementation of finite-state machines.

    PubMed

    Hjelmfelt, A; Weinberger, E D; Ross, J

    1992-01-01

    With methods developed in a prior article on the chemical kinetic implementation of a McCulloch-Pitts neuron, connections among neurons, logic gates, and a clocking mechanism, we construct examples of clocked finite-state machines. These machines include a binary decoder, a binary adder, and a stack memory. An example of the operation of the binary adder is given, and the chemical concentrations corresponding to the state of each chemical neuron are followed in time. Using these methods, we can, in principle, construct a universal Turing machine, and these chemical networks inherit the halting problem

  10. Sugar-based molecular computing by material implication.

    PubMed

    Elstner, Martin; Axthelm, Jörg; Schiller, Alexander

    2014-07-01

    A method to integrate an (in principle) unlimited number of molecular logic gates to construct complex circuits is presented. Logic circuits, such as half- or full-adders, can be reinterpreted by using the functional completeness of the implication function (IMP) and the trivial FALSE operation. The molecular gate IMP is represented by a fluorescent boronic acid sugar probe. An external wiring algorithm translates the fluorescent output from one gate into a chemical input for the next gate on microtiter plates. This process is demonstrated on a four-bit full adder. PMID:24924187

  11. Chemical Implementation of Finite-State Machines

    NASA Astrophysics Data System (ADS)

    Hjelmfelt, Allen; Weinberger, Edward D.; Ross, John

    1992-01-01

    With methods developed in a prior article on the chemical kinetic implementation of a McCulloch-Pitts neuron, connections among neurons, logic gates, and a clocking mechanism, we construct examples of clocked finite-state machines. These machines include a binary decoder, a binary adder, and a stack memory. An example of the operation of the binary adder is given, and the chemical concentrations corresponding to the state of each chemical neuron are followed in time. Using these methods, we can, in principle, construct a universal Turing machine, and these chemical networks inherit the halting problem

  12. Snake venom neutralization by Indian medicinal plants (Vitex negundo and Emblica officinalis) root extracts.

    PubMed

    Alam, M I; Gomes, A

    2003-05-01

    The methanolic root extracts of Vitex negundo Linn. and Emblica officinalis Gaertn. were explored for the first time for antisnake venom activity. The plant (V. negundo and E. officinalis) extracts significantly antagonized the Vipera russellii and Naja kaouthia venom induced lethal activity both in in vitro and in vivo studies. V. russellii venom-induced haemorrhage, coagulant, defibrinogenating and inflammatory activity was significantly neutralized by both plant extracts. No precipitating bands were observed between the plant extract and snake venom. The above observations confirmed that the plant extracts possess potent snake venom neutralizing capacity and need further investigation.

  13. Biochemical and biological activities of the venom of a new species of pitviper from Vietnam, Triceratolepidophis sieversorum.

    PubMed

    Mebs, Dietrich; Kuch, Ulrich; Herrmann, Hans Werner; Ziegler, Thomas

    2003-02-01

    Biochemical and biological activities of a venom sample from a recently discovered new genus and species of pitviper from Vietnam, Triceratolepidophis sieversorum, were assayed and compared with those of five other viperid snakes (Bothrops asper, Crotalus atrox, Protobothrops flavoviridis, Trimeresurus insularis, and Vipera ammodytes). The venom had high casein hydrolysis, arginine ester hydrolysis and haemorrhagic activities, lacked measurable phosphodiesterase and L-amino acid oxidase activities, and had no procoagulant activity on either bovine fibrinogen or human plasma. Other enzymatic activities (phospholipase A(2), kallikrein) were moderate. The approximate i.p. LD(50) (mice) of the venom is about 5-6 mg/kg. PMID:12565732

  14. Fast Arithmetic Using Signed Digit Numbers and Ternary Logic

    NASA Astrophysics Data System (ADS)

    Saxena, Rakesh Kumar; Sharma, Neelam; Wadhwani, A. K.

    2009-07-01

    Redundant Binary Signed Digit Number System may not be convenient for manual computations but may be useful in designing high-speed arithmetic machines. This number system is gaining popularity in computationally intensive environments particularly due to possessing of the carry-free addition/subtraction properties. This property has enabled arithmetic operations such as addition, multiplication, division, square root, etc., to be performed much faster than with conventional binary number systems. In RBSD number system carry propagation chains are eliminated which reduces the computational time substantially, thus enhancing the speed of the machine. The credit of RBSD number system goes to Robertson, who proposed it in 1959 and Avizienis in 1961. In this paper, some of the recent contributions in the area of design of redundant arithmetic based addition and multiplication algorithms and architectures are briefly discussed. Also use of parallel implementation for architectures is discussed so that the enhancement in speed through the use of redundant arithmetic is possible. Also, in this paper, RBSD adder is designed. After calculation and comparison it is concluded that efficiency of RBSD adder is much better than the other adders. An addition of two's complement circuit will make an RBSD subtractor. These Adders/Subtractors can further be used as building blocks for fast multiplication, division and square root operation.

  15. A Digitally Addressable Random-Access Image Selector and Random-Access Audio System.

    ERIC Educational Resources Information Center

    Bitzer, Donald L.; And Others

    The requirements of PLATO IV, a computer based education system at the University of Illinois, have led to the development of an improved, digitally addressable, random access image selector and a digitally addressable, random access audio device. Both devices utilize pneumatically controlled mechanical binary adders to position the mecahnical…

  16. 75 FR 35786 - White River Minimum Flows-Addendum to Final Determination of Federal and Non-Federal Hydropower...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-23

    ... prices it is using to value the Ozark Beach hydroelectric facility lost energy. This would be calculated... price of energy is approximately $10 per MWh factored up to $12.50 per MWh for the loss of an in-state.... Comment. ``SWPA should include a $12.50 per MWH adder escalating at 2.1% per year to Platt's energy...

  17. Labor costing for HANDI 2000 business management system

    SciTech Connect

    Wilson, D.

    1998-08-24

    Costing labor in the Financial Data System has traditionally been done using standard rates based on type of employee by organization. This methodology will change with the implementation of the PeopleSoft financial system. Labor in the new environment will be cost against actual dollars and marked up with an employee adder, to cover absences and fringe benefits.

  18. Integration of graphene oxide and DNA as a universal platform for multiple arithmetic logic units.

    PubMed

    Wang, Kun; Ren, Jiangtao; Fan, Daoqing; Liu, Yaqing; Wang, Erkang

    2014-11-28

    By a combination of graphene oxide and DNA, a universal platform was developed for integration of multiple logic gates to implement both half adder and half subtractor functions. A constant undefined threshold range between high and low fluorescence output signals was set for all the developed logic gates.

  19. Quantitative Proteomic Analysis of Venoms from Russian Vipers of Pelias Group: Phospholipases A2 are the Main Venom Components

    PubMed Central

    Kovalchuk, Sergey I.; Ziganshin, Rustam H.; Starkov, Vladislav G.; Tsetlin, Victor I.; Utkin, Yuri N.

    2016-01-01

    Venoms of most Russian viper species are poorly characterized. Here, by quantitative chromato-mass-spectrometry, we analyzed protein and peptide compositions of venoms from four Vipera species (V. kaznakovi, V. renardi, V. orlovi and V. nikolskii) inhabiting different regions of Russia. In all these species, the main components were phospholipases A2, their content ranging from 24% in V. orlovi to 65% in V. nikolskii. Altogether, enzyme content in venom of V. nikolskii reached ~85%. Among the non-enzymatic proteins, the most abundant were disintegrins (14%) in the V. renardi venom, C-type lectin like (12.5%) in V. kaznakovi, cysteine-rich venom proteins (12%) in V. orlovi and venom endothelial growth factors (8%) in V. nikolskii. In total, 210 proteins and 512 endogenous peptides were identified in the four viper venoms. They represented 14 snake venom protein families, most of which were found in the venoms of Vipera snakes previously. However, phospholipase B and nucleotide degrading enzymes were reported here for the first time. Compositions of V. kaznakovi and V. orlovi venoms were described for the first time and showed the greatest similarity among the four venoms studied, which probably reflected close relationship between these species within the “kaznakovi” complex. PMID:27077884

  20. Factor V activation and inactivation by venom proteases.

    PubMed

    Rosing, J; Govers-Riemslag, J W; Yukelson, L; Tans, G

    2001-01-01

    Blood coagulation factor V is a single-chain glycoprotein with M(r) = 330,000 which plays an important role in the procoagulant and anticoagulant pathways. Thrombin activates factor V into factor Va, a two-chain molecule which is composed of a heavy (M(r) = 105,000) and a light chain (M(r) = 71,000/74,000). Factor Va accelerates factor Xa-catalysed prothrombin activation more than 1,000-fold and under physiological conditions the cofactor activity of factor Va in prothrombin activation is down-regulated by activated protein C. Factor V can also be activated by a wide variety of snake venoms (e.g. from Vipera species, Naja naja oxiana, Bothrops atrox) and by proteases present in the bristles of a South American caterpillar (Lonomia achelous). Some venoms, notably of Vipera lebetina turanica and Lonomia achelous, contain proteases that are able to inactivate factor V or factor Va. Venom factor V activators are excellent tools in studying the structure-function relationship of factor V(a) and they are also used in diagnostic tests for quantification of plasma factor V levels and for the screening of defects in the protein C pathway. In this review, the structural and functional properties of animal venom factor V activators and inactivators is described. PMID:11910191

  1. Ten years of snakebites in Iran.

    PubMed

    Dehghani, Rouhullah; Fathi, Behrooz; Shahi, Morteza Panjeh; Jazayeri, Mehrdad

    2014-11-01

    Many species of venomous snakes are found in Iran. The most medically important species which are responsible for the most snakebite incidents in Iran belong to the Viperidae family, including Vipera lebetina, Echis carinatus, Pseudocerastes persicus, Vipera albicornuta and the Elapidae family, especially Naja naja oxiana. At least one kind of venomous snake is found in each of the 31 provinces, and many provinces have more than one venomous species. As a result, snakebite is a considerable health hazard in Iran, especially in the rural area of south and south-west of Iran. A retrospective, descriptive study of snakebite in Iran during 2002-2011 was carried out in order based on data collected from medical records of bite victims admitted to hospitals and health centers. From 2002 to 2011, 53,787 cases of snake bites were reported by medical centers in Iran. The annual incidence of snake bites in 100,000 of population varied from 4.5 to 9.1 during this decade and the number of recorded deaths were about 67 cases. The highest rate of snakebite was found in provinces of south and southwest of Iran. We suggest that people, especially in the rural areas, need to be trained and educated about venomous snakes, their hazards, prevention of bite and the importance of early hospital referral and treatment of victims. Also adequate antivenins as the main life saving medicine should be made available based on the recorded numbers of victims in each area of the country.

  2. Use of Pavo cristatus feather extract for the better management of snakebites: neutralization of inflammatory reactions.

    PubMed

    Murari, Satish K; Frey, Felix J; Frey, Brigitte M; Gowda, There V; Vishwanath, Bannikuppe S

    2005-06-01

    In Indian traditional medicine, peacock feather in the form of ash (Bhasma) or water extract are used against snakebite and to treat various problems associated with lungs. This study was aimed to evaluate the water extract of peacock feather (PCF) against the local tissue damage caused due to snakebite. PCF water extract showed inhibition towards phospholipase A2 enzyme activity from snake venom (Naja naja and Vipera russelii), inflammatory fluids (synovial, pleural, ascites) and normal serum in a dose-dependent manner. Hyaluronidase and proteases are other major enzymes in snake venoms responsible for local tissue damage. PCF water extract inhibited hyaluronidase and proteolytic enzyme activities from Vipera russelii, Naja naja and Trimeresurus malabaricus venom. The active principle is a hydrophilic molecule easily extractable in water or polar solvents. PCF water extract gave positive results for the presence of protein and secondary metabolites like carotenoids and steroids. Analysis of metal ions revealed that iron is the major ion (> 20-fold). Other metal ions detected in smaller amount are copper, chromium, zinc and nickel. The least amount of ion detected is gold. Co-injection of PCF water extract with snake venom and inflammatory PLA2 enzymes neutralize the edema inducing activity of all the PLA2 enzymes studied. Since it inhibits hyaluronidase and proteases enzyme activity from snake venom PCF water extract is a powerful neutralizing agent, which has therapeutic application against venom toxicity.

  3. Design and implementation of photon correlator based on C8051F

    NASA Astrophysics Data System (ADS)

    Shen, Jin; Li, Yuming; Liu, Wei; Yang, Yan; Cheng, Yanting

    2008-02-01

    Correlation techniques are widely used to extract spectral information from light scattering and other stochastic processes. Within the photon correlation system, the correlating operation must work at a high speed. In this paper, a photon correlator based on microcontroller C8051F was developed. In the photon correlator, the work of counting and scratch is completed by the two 4-bits binary adder 74F161, which is connected to form an 8-bits adder., and the correlation operation of every channel is carried out by the software of C8051F. By probably choosing high speed devices counting of 10ns in width pulses can be counted. The correlation operations including multiplying and addition operation of 56 channels with the circulation program within 3μs were made in interrupt service routine of the C8051F. The work in this paper can be applied in the ultra-fine particle sizing with photon correlation spectroscopy.

  4. Neural network chips for trigger purposes in high energy physics

    SciTech Connect

    Gemmeke, H.; Eppler, W.; Fischer, T.

    1996-12-31

    Two novel neural chips SAND (Simple Applicable Neural Device) and SIOP (Serial Input - Operating Parallel) are described. Both are highly usable for hardware triggers in particle physics. The chips are optimized for a high input data rate at a very low cost basis. The performance of a single SAND chip is 200 MOPS due to four parallel 16 bit multipliers and 40 bit adders working in one clock cycle. The chip is able to implement feedforward neural networks, Kohonen feature maps and radial basis function networks. Four chips will be implemented on a PCI-board for simulation and on a VUE board for trigger and on- and off-line analysis. For small sized feedforward neural networks the bit-serial neuro-chip SIOP may lead to even smaller latencies because each synaptic connection is implemented by its own bit serial multiplier and adder.

  5. ZX Pulsed-Power Design

    SciTech Connect

    Corley, J.P.; Johnson, D.L.; McDaniel, D.H.; Spielman, R.B.; Struve, K.W.; Stygar, W.A.

    1999-08-02

    ZX is a new z-pinch accelerator planned as the next generation z-pinch driver at SNL, and as an intermediate step towards X-1. It is planned to drive either a single 50 MA z-pinch load, or two 25 to 30 MA z pinches. Three designs for the ZX accelerator are presented. All require 7 to 8 MV at the insulator stack to drive the z-pinch load to implosion in 100 to 120 ns. Two of the designs are based on the Z accelerator, and use water-line technology; a transit-time-isolated water adder, and a water transformer. The third design uses inductive-voltage adders in water. They also describe a low-inductance insulator stack design that helps minimize voltage requirements. This design is evaluated for water and vacuum break-down using JCM, THM, and magnetic-flashover-inhibition criteria.

  6. System for adjusting frequency of electrical output pulses derived from an oscillator

    DOEpatents

    Bartholomew, David B.

    2006-11-14

    A system for setting and adjusting a frequency of electrical output pulses derived from an oscillator in a network is disclosed. The system comprises an accumulator module configured to receive pulses from an oscillator and to output an accumulated value. An adjustor module is configured to store an adjustor value used to correct local oscillator drift. A digital adder adds values from the accumulator module to values stored in the adjustor module and outputs their sums to the accumulator module, where they are stored. The digital adder also outputs an electrical pulse to a logic module. The logic module is in electrical communication with the adjustor module and the network. The logic module may change the value stored in the adjustor module to compensate for local oscillator drift or change the frequency of output pulses. The logic module may also keep time and calculate drift.

  7. Investigations on the vacuum current in the magnetic insulated Karlsruhe light ion facility high-energy linear induction accelerator (KALIF-HELIA)

    NASA Astrophysics Data System (ADS)

    Illy, S.; Kuntz, M.; Westermann, T.

    1994-08-01

    In order to increase the applied voltage in pulsed power ion diodes, the Karlsruhe light ion facility will be extended by a voltage adder. An important problem with such a device is how the electron loss current can be controlled in the vacuum feed. Based on a static, one-dimensional analytic model and two-dimensional particle-in-cell (PIC) simulations, a detailed knowledge of the electron flow in the voltage adder is obtained. Time-dependent simulations support qualitatively the observation of laminar electron flow. The electrons form a band corresponding to the section on which they originate. It is demonstrated that with the introduction of guard rings, appropriately positioned in the feed, the electron loss current can be reduced by more than 50%.

  8. Reconfigurable and resettable arithmetic logic units based on magnetic beads and DNA.

    PubMed

    Zhang, Siqi; Wang, Kun; Huang, Congcong; Sun, Ting

    2015-12-28

    Based on the characteristics of magnetic beads and DNA, a simple and universal platform was developed for the integration of multiple logic gates to achieve resettable half adder and half subtractor functions. The signal reporter was composed of a split G-quadruplex DNAzyme and AuNP-surface immobilized molecular beacon molecule. The novel feature of the designed system is that the inputs (split G-quadruplexes) can interact with hairpin-modified Au NPs linked to magnetic particles. Another novel feature is that the logic operations can be reset by heating the output system and by using the magnetic separation of the computing modules. Moreover, the developed half adder and half subtractor are realized on a simple DNA/magnetic bead platform in an enzyme-free system and share a constant threshold setpoint. Due to the diversity and design flexibility of DNA, these investigations may provide a new method for the development of resettable DNA-based arithmetic operations.

  9. PRINCIPLE DESIGN OF 300KHZ MECO RF KICKER BIPOLAR SOLID STATE MODULATOR.

    SciTech Connect

    ZHANG,W.; KOTLYAR,Y.

    2004-05-23

    A high speed, high repetition rate, bipolar solid-state high voltage modulator is under development at Brookhaven National Laboratory for Muon Electron Conversion (MECO) Experiment. The modulator will be used to drive a RF kicker consisting a pair of parallel deflecting plates. The principle design is based on the inductive-adder topology. This system requires a fast pulse rise and fall time about 20ns, a pulse width of 100ns, a pulse repetition rate of 300 kHz, and a 60 kHz sine-wave amplitude modulation. The fast high voltage MOSFETs are used as main switching devices.Different magnetic materials are being investigated for adder core magnets. The main circuit design, critical subsystems, and major technical issues will be discussed. The circuit simulation, components selection and evaluation, and preliminary test results will be presented.

  10. Amplitude Control of Solid-State Modulators for Precision Fast Kicker Applications

    SciTech Connect

    Watson, J A; Anaya, R M; Caporaso, G C; Chen, Y J; Cook, E G; Lee, B S; Hawkins, A

    2002-11-15

    A solid-state modulator with very fast rise and fall times, pulse width agility, and multi-pulse burst and intra-pulse amplitude adjustment capability for use with high speed electron beam kickers has been designed and tested at LLNL. The modulator uses multiple solid-state modules stacked in an inductive-adder configuration. Amplitude adjustment is provided by controlling individual modules in the adder, and is used to compensate for transverse e-beam motion as well as the dynamic response and beam-induced steering effects associated with the kicker structure. A control algorithm calculates a voltage based on measured e-beam displacement and adjusts the modulator to regulate beam centroid position. This paper presents design details of amplitude control along with measured performance data from kicker operation on the ETA-II accelerator at LLNL.

  11. Wavelet analysis and HHG in nanorings: their applications in logic gates and memory mass devices

    NASA Astrophysics Data System (ADS)

    Cricchio, Dario; Fiordilino, Emilio

    2016-01-01

    We study the application of one nanoring driven by a laser field in different states of polarization in logic circuits. In particular we show that assigning Boolean values to different states of the incident laser field and to the emitted signals, we can create logic gates such as OR, XOR and AND. We also show the possibility of making logic circuits such as half-adder and full-adder using one and two nanorings respectively. Using two nanorings we made the Toffoli gate. Finally we use the final angular momentum acquired by the electron to store information and hence show the possibility of using an array of nanorings as a mass memory device.

  12. Advances in post AFM repair cleaning of photomask with CO2 cryogenic aerosol technology

    NASA Astrophysics Data System (ADS)

    Bowers, Charles; Varghese, Ivin; Balooch, Mehdi; Brandt, Werner

    2009-04-01

    As the mask technology matures, critical printing features and sub-resolution assist features (SRAF) shrink below 100 nm, forcing critical cleaning processes to face significant challenges. These challenges include use of new materials, oxidation, chemical contamination sensitivity, proportionally decreasing printable defect size, and a requirement for a damage-free clean. CO2 cryogenic aerosol cleaning has the potential to offer a wide process window for meeting these new challenges, if residue adder issues and damage can be eliminated. Some key differentiations of CO2 cryogenic aerosol cleaning are the non-oxidizing and non-etching properties compared to conventional chemical wet clean processes with or without megasonics. In prior work, the feasibility of CO2 cryogenic aerosol in post AFM repair photomask cleaning was demonstrated. In this paper, recent advancements of CO2 cryogenic aerosol cleaning technology are presented, focusing on the traditional problem areas of particle adders, electrostatic discharge (ESD), and mask damage mitigation. Key aspects of successful CO2 cryogenic aerosol cleaning include the spray nozzle design, CO2 liquid purity, and system design. The design of the nozzle directly controls the size, density, and velocity of the CO2 snow particles. Methodology and measurements of the solid CO2 particle size and velocity distributions will be presented, and their responses to various control parameters will be discussed. Adder control can be achieved only through use of highly purified CO2 and careful materials selection. Recent advances in CO2 purity will be discussed and data shown. The mask cleaning efficiency by CO2 cryogenic aerosol and damage control is essentially an optimization of the momentum of the solid CO2 particles and elimination of adders. The previous damage threshold of 150 nm SRAF structures has been reduced to 70nm and data will be shown indicating 60 nm is possible in the near future. Data on CO2 tribocharge mitigation

  13. Logic operations in a doped solid driven by stimulated Raman adiabatic passage

    SciTech Connect

    Beil, F.; Halfmann, T.; Remacle, F.; Levine, R. D.

    2011-03-15

    We experimentally demonstrate classical-optical logic operations in a solid-state memory, coherently driven by variants of stimulated Raman adiabatic passage (STIRAP). Cyclic transfer of atomic populations permits the implementation of a flip-flop or xor gate, with up to eight optical input operations. Observation of stimulated emission as an additional output channel enables the setup of a STIRAP-driven full adder for three optical input bits (or two input bits and a memory bit).

  14. Quantum Realization of Arnold Scrambling for IFRQI

    NASA Astrophysics Data System (ADS)

    Sang, Jianzhi; Wang, Shen; Shi, Xue; Li, Qiong

    2016-08-01

    This paper is concerned with the feasibility of the Arnold scrambling based on Improved Flexible Representation of Quantum Images (IFRQI). Firstly, the flexible representation of quantum image is updated to the improved flexible representation of quantum image (IFRQI) to represent a quantum image with arbitrary size L × B. Then, by making use of Control-NOT gate and Adder-Modular operation, the concrete quantum circuit of Arnold scrambling for IFRQI is designed. Simulation results show the effectiveness of the proposed circuit.

  15. Terahertz-optical-asymmetric-demultiplexer (TOAD)-based arithmetic units for ultra-fast optical information processing

    NASA Astrophysics Data System (ADS)

    Cherri, Abdallah K.

    2010-04-01

    In this paper, designs of ultra-fast all-optical based Terahertz-optical-asymmetric-demultiplexer (TOAD)-based devices are reported. Using TOAD switches, adders/subtracters units are demonstrated. The high speed is achieved due to the use of the nonlinear optical materials and the nonbinary modified signed-digit (MSD) number representation. The proposed all-optical circuits are compared in terms of numbers TOAD switches, optical amplifiers and wavelength converters.

  16. DUMPING COOLED MOLDS FROM THE SHAKE OUT RAILS ONTO A ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    DUMPING COOLED MOLDS FROM THE SHAKE OUT RAILS ONTO A VIBRATING CONVEYOR WHICH TRANSPORTS CASTINGS AND SAND TO A SEPARATION SCREEN WHICH SIFTS SAND ONTO BELT CONVEYORS BELOW THAT CARRY IT PAST SWITCH-ACTIVATED WATER INJECTORS TO SIMILAR SWITCH-ACTIVATED FRESH SAND ADDERS BEFORE TRANSPORTING IT TO THE SAND STORAGE BIN WHILE CASTINGS ARE EITHER MANUALLY OR SMALL CRANE LIFTED TO DEGATING AREAS. - Southern Ductile Casting Company, Centerville Foundry, 101 Airport Road, Centreville, Bibb County, AL

  17. Extraction Kickers and Modulators for the advanced Hydrodynamic Facility

    SciTech Connect

    Walstrom, P L; Cook, E G

    2001-06-12

    In order to exploit the full potential of the Advanced Hydrodynamic Facility (AHF) facility to produce a time sequence of proton transmission radiographs throughout the dynamic event, a kicker/modulator for extraction from the 50 GeV ring that is capable of generating a string of 25 pulse pairs at arbitrary times within a total time duration of 100 microseconds or more is desired. The full range of desired pulse-train requirements cannot be met with the commonly used pulse-forming cables or networks (PFNs) switched with thyratrons. The preferred modulator design approach at present is a transformer voltage-adder concept with primary-side pulses formed with MOSFET-switched capacitors. This modulator will be a scale-up of an existing modulator that has been developed by Lawrence Livermore National Laboratory for use in DARHT, an electron induction accelerator facility at Los Alamos National Laboratory. Before the voltage-adder concept can be adopted for use in AHF, a working prototype that meets the AHF requirements for the pulse voltage, current, rise and fall time, and total pulse number must be built and tested. Additional requirements for pulse-to-pulse flattop height variation and baseline shift must also be met. A development and testing plan for the voltage-adder kicker modulator for AHF is described.

  18. A hardware implementation of the discrete Pascal transform for image processing

    NASA Astrophysics Data System (ADS)

    Goodman, Thomas J.; Aburdene, Maurice F.

    2006-02-01

    The discrete Pascal transform is a polynomial transform with applications in pattern recognition, digital filtering, and digital image processing. It already has been shown that the Pascal transform matrix can be decomposed into a product of binary matrices. Such a factorization leads to a fast and efficient hardware implementation without the use of multipliers, which consume large amounts of hardware. We recently developed a field-programmable gate array (FPGA) implementation to compute the Pascal transform. Our goal was to demonstrate the computational efficiency of the transform while keeping hardware requirements at a minimum. Images are uploaded into memory from a remote computer prior to processing, and the transform coefficients can be offloaded from the FPGA board for analysis. Design techniques like as-soon-as-possible scheduling and adder sharing allowed us to develop a fast and efficient system. An eight-point, one-dimensional transform completes in 13 clock cycles and requires only four adders. An 8x8 two-dimensional transform completes in 240 cycles and requires only a top-level controller in addition to the one-dimensional transform hardware. Finally, through minor modifications to the controller, the transform operations can be pipelined to achieve 100% utilization of the four adders, allowing one eight-point transform to complete every seven clock cycles.

  19. The Synchronization of Replication and Division Cycles in Individual E. coli Cells.

    PubMed

    Wallden, Mats; Fange, David; Lundius, Ebba Gregorsson; Baltekin, Özden; Elf, Johan

    2016-07-28

    Isogenic E. coli cells growing in a constant environment display significant variability in growth rates, division sizes, and generation times. The guiding principle appears to be that each cell, during one generation, adds a size increment that is uncorrelated to its birth size. Here, we investigate the mechanisms underlying this "adder" behavior by mapping the chromosome replication cycle to the division cycle of individual cells using fluorescence microscopy. We have found that initiation of chromosome replication is triggered at a fixed volume per chromosome independent of a cell's birth volume and growth rate. Each initiation event is coupled to a division event after a growth-rate-dependent time. We formalize our findings in a model showing that cell-to-cell variation in division timing and cell size is mainly driven by variations in growth rate. The model also explains why fast-growing cells display adder behavior and correctly predict deviations from the adder behavior at slow growth. PMID:27471967

  20. All-optical digital logic: Full addition or subtraction on a three-state system

    SciTech Connect

    Remacle, F.; Levine, R. D.

    2006-03-15

    Stimulated Raman adiabatic passage (STIRAP) is a well-studied pump-probe control scheme for manipulating the population of quantum states of atoms or molecules. By encoding the digits to be operated on as 'on' or 'off' laser input signals we show how STIRAP can be used to implement a finite-state logic machine. The physical conditions required for an effective STIRAP operation are related to the physical conditions expected for a logic machine. In particular, a condition is derived on the mean number of photons that represent an on pulse. A finite-state machine computes Boolean expressions that depend both on the input and on the present state of the machine. With two input signals we show how to implement a full adder where the carry-in digit is stored in the state of the machine. Furthermore, we show that it is possible to store the carry-out digit as the next state and thereby return the machine to a state ready for the next full addition. Such a machine operates as a cyclical full adder. We further show how this full adder can equally well be operated as a full subtractor. To the best of our knowledge this is the first example of a nanosized system that implements a full subtraction.

  1. Dynamic SVL and body bias for low leakage power and high performance in CMOS digital circuits

    NASA Astrophysics Data System (ADS)

    Deshmukh, Jyoti; Khare, Kavita

    2012-12-01

    In this article, a new complementary metal oxide semiconductor design scheme called dynamic self-controllable voltage level (DSVL) is proposed. In the proposed scheme, leakage power is controlled by dynamically disconnecting supply to inactive blocks and adjusting body bias to further limit leakage and to maintain performance. Leakage power measurements at 1.8 V, 75°C demonstrate power reduction by 59.4% in case of 1 bit full adder and by 43.0% in case of a chain of four inverters using SVL circuit as a power switch. Furthermore, we achieve leakage power reduction by 94.7% in case of 1 bit full adder and by 91.8% in case of a chain of four inverters using dynamic body bias. The forward body bias of 0.45 V applied in active mode improves the maximum operating frequency by 16% in case of 1 bit full adder and 5.55% in case of a chain of inverters. Analysis shows that additional benefits of using the DSVL and body bias include high performance, low leakage power consumption in sleep mode, single threshold implementation and state retention even in standby mode.

  2. Status of magnetically-insulated power transmission theory

    SciTech Connect

    Mendel, C.W. Jr.

    1995-12-31

    The theory of magnetically-insulated power flow has improved dramatically over the last two decades since the early works of Creedon, Lovelace and Ott, Ron, Mondelli, and Rostoker, and of Bergeron. During the intervening years theoretical improvements included a complete general kinetic theory that involved distributions of electrons based on quasi-conserved canonical variables and was used to study flow stability and to analyze simulations and pulsers with voltage adders. The status of theory at this time allowed them to understand many features of these flows, but did not allow detailed analysis for design and data interpretation. Recent theoretical advances have drastically changed this situation. Two recent static models based on layered flows have allowed them to understand and to improve power coupling in voltage adders, current adders, plasma opening switches and in systems where the vacuum impedance varies along the flow. A dynamic model based upon electrons flowing in one or more thin layers has permitted detailed self-consistent time-dependent calculations which include electron flow. This model accurately predicts experimental and simulational data.

  3. Adjuvant effects and antiserum action potentiation by a (herbal) compound 2-hydroxy-4-methoxy benzoic acid isolated from the root extract of the Indian medicinal plant 'sarsaparilla' (Hemidesmus indicus R. Br.).

    PubMed

    Alam, M I; Gomes, A

    1998-10-01

    The adjuvant effect and antiserum potentiation of a compound 2-hydroxy-4-methoxy benzoic acid were explored in the present investigation. This compound, isolated and purified from the Indian medicinal plant Hemidesmus indicus R. Br, possessed antisnake venom activity. Rabbits immunized with Vipera russellii venom in the presence and absence of the compound along with Freund's complete adjuvant, produced a precipitating band in immunogel diffusion and immunogel electrophoresis. The venom neutralizing capacity of this antiserum showed positive adjuvant effects as evident by the higher neutralization capacity (lethal and hemorrhage) when compared with the antiserum raised with venom alone. The pure compound potentiated the lethal action neutralization of venom by commercial equine polyvalent snake venom antiserum in experimental models. These observations raised the possibility of the use of chemical antagonists (from herbs) against snake bite, which may provide a better protection in presence of antiserum, especially in the rural parts of India.

  4. Neutralization of local and systemic toxicity of Daboia russelii venom by Morus alba plant leaf extract.

    PubMed

    Chandrashekara, K T; Nagaraju, S; Nandini, S Usha; Kemparaju, K

    2009-08-01

    Antivenom therapy is the current best therapy available for the treatment of fatal snake envenomation. However, the antivenom offers less or no protection against local effects such as extensive edema, hemorrhage, dermo-, myonecrosis and inflammation at the envenomed region. Viperidae snakes are highly known for their violent local effects and such effects have been commonly treated with plant extracts without any scientific validation in rural India. In this investigation Morus alba plant leaf extract has been studied against the Indian Vipera/Daboia russelii venom induced local and systemic effects. The extract completely abolished the in vitro proteolytic and hyaluronolytic activities of the venom. Edema, hemorrhage and myonecrotic activities were also neutralized efficiently. In addition, the extract partially inhibited the pro-coagulant activity and completely abolished the degradation of Aalpha chain of human fibrinogen. Thus, the extract processes potent antisnake venom property, especially against the local and systemic effects of Daboia russelii venom.

  5. Evolution of phospholipase A2 toxins in venomous animals.

    PubMed

    Kordiš, Dušan

    2011-12-01

    Franc Gubenšek devoted much of his research career to the phospholipases A2 (PLA2), which are the major pharmacologically active components of snake venoms. Our long collaboration started with an analysis of Vipera ammodytes ammodytoxin and ammodytin cDNAs and genes. These PLA2 genes provided us with an entry into the exciting area of molecular evolution. We studied the structures of the PLA2 genes, the evolution of multigene families encoding PLA2 toxins, and the horizontal transfer of unusual retroelements that we found in these genes. In the last decade a number of novel features have emerged concerning the evolution of PLA2s in venomous animals. The large amount of recently accumulated data has provided a timely opportunity to review current understanding of the evolution of PLA2 toxins in venomous animals.

  6. Direct nephrotoxicity of Russell's viper venom demonstrated in the isolated perfused rat kidney.

    PubMed

    Ratcliffe, P J; Pukrittayakamee, S; Ledingham, J G; Warrell, D A

    1989-03-01

    Envenoming by Russell's Viper (Vipera russelli) is an important cause of acute renal failure. The mechanism of renal damage is unresolved. It is difficult to obtain evidence of a direct nephrotoxic action because of the coincidental disturbance to the systemic circulation. We studied the action of Russell's Viper venom on the function of the isolated perfused rat kidney. Direct nephrotoxic action was indicated by a dose dependent decrease in inulin clearance and an increase in fractional excretion of sodium seen at venom concentrations down to 50 ng/ml, a concentration likely to be achieved in the human circulation after envenoming. The isolated perfused kidney was also used to assess the efficiency of antivenom and for a comparison with snake venoms from the Thai cobra (Naja kauothia) and the Nigerian Saw-Scaled Viper (Echis ocellatus). PMID:2929855

  7. Trimeresurus venom inhibition of anti-HPA-1a and anti-HPA-1b antibody binding to human platelets.

    PubMed

    Wlodar, S J; Stone, D L; Sinor, L T

    1995-01-01

    A solid-phase red cell adherence assay was used to demonstrate the specific inhibitory effect of seven species of Trimeresurus snake venom on the binding of HPA-1a- and HPA-1b-specific platelet antibodies. Trimeresurus venom did not inhibit the binding of HLA-, HPA-3a-, HPA-3b-, HPA-4a-, HPA-5a-, and HPA-5b-specific platelet antibodies. Venom from other genera of snakes, including representatives from Agkistrodon, Ancistrodon, Bitis, Bothrops, Bungarus, Causus, Crotalus, Dendroaspis, Ecis, Micrurus, Naja, Notechis, Ophiophagus, Pseudechis, Sepedon (Hemachatus), and Vipera, all failed to specifically inhibit anti-HPA-1a and HPA-1b binding. These results may indicate that the component in Trimeresurus snake venom previously reported to bind to the platelet GPIIb-IIIa complex, inhibiting fibrinogen binding, binds close to the HPA-1a and HPA-1b epitopes.

  8. Architecture Framework for Trapped-Ion Quantum Computer based on Performance Simulation Tool

    NASA Astrophysics Data System (ADS)

    Ahsan, Muhammad

    The challenge of building scalable quantum computer lies in striking appropriate balance between designing a reliable system architecture from large number of faulty computational resources and improving the physical quality of system components. The detailed investigation of performance variation with physics of the components and the system architecture requires adequate performance simulation tool. In this thesis we demonstrate a software tool capable of (1) mapping and scheduling the quantum circuit on a realistic quantum hardware architecture with physical resource constraints, (2) evaluating the performance metrics such as the execution time and the success probability of the algorithm execution, and (3) analyzing the constituents of these metrics and visualizing resource utilization to identify system components which crucially define the overall performance. Using this versatile tool, we explore vast design space for modular quantum computer architecture based on trapped ions. We find that while success probability is uniformly determined by the fidelity of physical quantum operation, the execution time is a function of system resources invested at various layers of design hierarchy. At physical level, the number of lasers performing quantum gates, impact the latency of the fault-tolerant circuit blocks execution. When these blocks are used to construct meaningful arithmetic circuit such as quantum adders, the number of ancilla qubits for complicated non-clifford gates and entanglement resources to establish long-distance communication channels, become major performance limiting factors. Next, in order to factorize large integers, these adders are assembled into modular exponentiation circuit comprising bulk of Shor's algorithm. At this stage, the overall scaling of resource-constraint performance with the size of problem, describes the effectiveness of chosen design. By matching the resource investment with the pace of advancement in hardware technology

  9. Champions of profitable growth.

    PubMed

    Stewart, G Bennett

    2004-01-01

    Many companies have posted impressive top-line growth over the past two decades in their respective economic regions--for instance, Wal-Mart in North America, BP in Europe, Toyota in Asia, and News Corporation in the Southern Hemisphere. But which were the best at converting all of that revenue growth into shareholder value? Harvard Business Review asked C. Bennett Stewart III, the senior partner of the consulting firm Stern Stewart & Company, and his colleagues to come up with the answer. For the period 1983 to 2003, they assembled a list of the top 20 high-growth value adders (and laggards) in each of the four regions cited above. Their calculations gave equal weight to companies' revenue growth and market-value-added scores, revealing the important effect of region on the performance of companies in the same industry. For instance, while automakers are positioned high on the Asian list of high-growth value adders, U.S. carmakers GM and Ford--each of which reported revenue growth in excess of 100 billion dollars between 1983 and 2003--are among the value laggards on the North American list, as are DaimlerChrysler and Volkswagen on the European list. The Japanese win through better efficiency, higher quality, and narrower product mixes, the author says. And while there are four telecom companies represented among the European high-growth value adders, there are none on the North American list. That's probably because the European telecoms enjoyed more protective regulation, made fewer high-priced acquisitions, and didn't bet as big on the overblown dot-com economy, the author says.

  10. Champions of profitable growth.

    PubMed

    Stewart, G Bennett

    2004-01-01

    Many companies have posted impressive top-line growth over the past two decades in their respective economic regions--for instance, Wal-Mart in North America, BP in Europe, Toyota in Asia, and News Corporation in the Southern Hemisphere. But which were the best at converting all of that revenue growth into shareholder value? Harvard Business Review asked C. Bennett Stewart III, the senior partner of the consulting firm Stern Stewart & Company, and his colleagues to come up with the answer. For the period 1983 to 2003, they assembled a list of the top 20 high-growth value adders (and laggards) in each of the four regions cited above. Their calculations gave equal weight to companies' revenue growth and market-value-added scores, revealing the important effect of region on the performance of companies in the same industry. For instance, while automakers are positioned high on the Asian list of high-growth value adders, U.S. carmakers GM and Ford--each of which reported revenue growth in excess of 100 billion dollars between 1983 and 2003--are among the value laggards on the North American list, as are DaimlerChrysler and Volkswagen on the European list. The Japanese win through better efficiency, higher quality, and narrower product mixes, the author says. And while there are four telecom companies represented among the European high-growth value adders, there are none on the North American list. That's probably because the European telecoms enjoyed more protective regulation, made fewer high-priced acquisitions, and didn't bet as big on the overblown dot-com economy, the author says. PMID:15241952

  11. Factors affecting the output pulse flatness of the linear transformer driver cavity systems with 5th harmonics

    NASA Astrophysics Data System (ADS)

    Alexeenko, V. M.; Mazarakis, M. G.; Kim, A. A.; Kondratiev, S. S.; Sinebryukhov, V. A.; Volkov, S. N.; Cuneo, M. E.; Kiefer, M. L.; Leckby, J. J.; Oliver, B. V.; Maloney, P. D.

    2016-09-01

    We describe the study we have undertaken to evaluate the effect of component tolerances in obtaining a voltage output flat top for a linear transformer driver (LTD) cavity containing 3rd and 5th harmonic bricks [A. A. Kim et al., in Proc. IEEE Pulsed Power and Plasma Science PPPS2013 (San Francisco, California, USA, 2013), pp. 1354-1356.] and for 30 cavity voltage adder. Our goal was to define the necessary component value precision in order to obtain a voltage output flat top with no more than ±0.5 % amplitude variation.

  12. Design of Wallace tree multiplier and other components of a quantum ALU using reversible TSG gate

    NASA Astrophysics Data System (ADS)

    Thapliyal, Himanshu; Srinivas, M. B.

    2006-05-01

    This paper presents the design of a novel modified Wallace tree multiplier, using the reversible TSG gate proposed by the authors earlier. The novelty of the TSG gate is that it can also work singly as a reversible full adder. The TSG gate is also used in this paper to design various other reversible arithmetic and logical components that can be assembled to realize a primitive reversible/quantum ALU. It is also shown that these components are optimal, in terms of number of reversible gates and garbage outputs, compared to other designs existing in literature.

  13. Serial multiplier arrays for parallel computation

    NASA Technical Reports Server (NTRS)

    Winters, Kel

    1990-01-01

    Arrays of systolic serial-parallel multiplier elements are proposed as an alternative to conventional SIMD mesh serial adder arrays for applications that are multiplication intensive and require few stored operands. The design and operation of a number of multiplier and array configurations featuring locality of connection, modularity, and regularity of structure are discussed. A design methodology combining top-down and bottom-up techniques is described to facilitate development of custom high-performance CMOS multiplier element arrays as well as rapid synthesis of simulation models and semicustom prototype CMOS components. Finally, a differential version of NORA dynamic circuits requiring a single-phase uncomplemented clock signal introduced for this application.

  14. Reconfigurable and resettable arithmetic logic units based on magnetic beads and DNA

    NASA Astrophysics Data System (ADS)

    Zhang, Siqi; Wang, Kun; Huang, Congcong; Sun, Ting

    2015-12-01

    Based on the characteristics of magnetic beads and DNA, a simple and universal platform was developed for the integration of multiple logic gates to achieve resettable half adder and half subtractor functions. The signal reporter was composed of a split G-quadruplex DNAzyme and AuNP-surface immobilized molecular beacon molecule. The novel feature of the designed system is that the inputs (split G-quadruplexes) can interact with hairpin-modified Au NPs linked to magnetic particles. Another novel feature is that the logic operations can be reset by heating the output system and by using the magnetic separation of the computing modules. Moreover, the developed half adder and half subtractor are realized on a simple DNA/magnetic bead platform in an enzyme-free system and share a constant threshold setpoint. Due to the diversity and design flexibility of DNA, these investigations may provide a new method for the development of resettable DNA-based arithmetic operations.Based on the characteristics of magnetic beads and DNA, a simple and universal platform was developed for the integration of multiple logic gates to achieve resettable half adder and half subtractor functions. The signal reporter was composed of a split G-quadruplex DNAzyme and AuNP-surface immobilized molecular beacon molecule. The novel feature of the designed system is that the inputs (split G-quadruplexes) can interact with hairpin-modified Au NPs linked to magnetic particles. Another novel feature is that the logic operations can be reset by heating the output system and by using the magnetic separation of the computing modules. Moreover, the developed half adder and half subtractor are realized on a simple DNA/magnetic bead platform in an enzyme-free system and share a constant threshold setpoint. Due to the diversity and design flexibility of DNA, these investigations may provide a new method for the development of resettable DNA-based arithmetic operations. Electronic supplementary information

  15. Computing with liquid crystal fingers: Models of geometric and logical computation

    NASA Astrophysics Data System (ADS)

    Adamatzky, Andrew; Kitson, Stephen; Costello, Ben De Lacy; Matranga, Mario Ariosto; Younger, Daniel

    2011-12-01

    When a voltage is applied across a thin layer of cholesteric liquid crystal, fingers of cholesteric alignment can form and propagate in the layer. In computer simulation, based on experimental laboratory results, we demonstrate that these cholesteric fingers can solve selected problems of computational geometry, logic, and arithmetics. We show that branching fingers approximate a planar Voronoi diagram, and nonbranching fingers produce a convex subdivision of concave polygons. We also provide a detailed blueprint and simulation of a one-bit half-adder functioning on the principles of collision-based computing, where the implementation is via collision of liquid crystal fingers with obstacles and other fingers.

  16. Implementation of Arithmetic and Nonarithmetic Functions on a Label-free and DNA-based Platform

    PubMed Central

    Wang, Kun; He, Mengqi; Wang, Jin; He, Ronghuan; Wang, Jianhua

    2016-01-01

    A series of complex logic gates were constructed based on graphene oxide and DNA-templated silver nanoclusters to perform both arithmetic and nonarithmetic functions. For the purpose of satisfying the requirements of progressive computational complexity and cost-effectiveness, a label-free and universal platform was developed by integration of various functions, including half adder, half subtractor, multiplexer and demultiplexer. The label-free system avoided laborious modification of biomolecules. The designed DNA-based logic gates can be implemented with readout of near-infrared fluorescence, and exhibit great potential applications in the field of bioimaging as well as disease diagnosis. PMID:27713517

  17. Energy-Efficient Wide Datapath Integer Arithmetic Logic Units Using Superconductor Logic

    NASA Astrophysics Data System (ADS)

    Ayala, Christopher Lawrence

    Complementary Metal-Oxide-Semiconductor (CMOS) technology is currently the most widely used integrated circuit technology today. As CMOS approaches the physical limitations of scaling, it is unclear whether or not it can provide long-term support for niche areas such as high-performance computing and telecommunication infrastructure, particularly with the emergence of cloud computing. Alternatively, superconductor technologies based on Josephson junction (JJ) switching elements such as Rapid Single Flux Quantum (RSFQ) logic and especially its new variant, Energy-Efficient Rapid Single Flux Quantum (ERSFQ) logic have the capability to provide an ultra-high-speed, low power platform for digital systems. The objective of this research is to design and evaluate energy-efficient, high-speed 32-bit integer Arithmetic Logic Units (ALUs) implemented using RSFQ and ERSFQ logic as the first steps towards achieving practical Very-Large-Scale-Integration (VLSI) complexity in digital superconductor electronics. First, a tunable VHDL superconductor cell library is created to provide a mechanism to conduct design exploration and evaluation of superconductor digital circuits from the perspectives of functionality, complexity, performance, and energy-efficiency. Second, hybrid wave-pipelining techniques developed earlier for wide datapath RSFQ designs have been used for efficient arithmetic and logic circuit implementations. To develop the core foundation of the ALU, the ripple-carry adder and the Kogge-Stone parallel prefix carry look-ahead adder are studied as representative candidates on opposite ends of the design spectrum. By combining the high-performance features of the Kogge-Stone structure and the low complexity of the ripple-carry adder, a 32-bit asynchronous wave-pipelined hybrid sparse-tree ALU has been designed and evaluated using the VHDL cell library tuned to HYPRES' gate-level characteristics. The designs and techniques from this research have been implemented using

  18. Universal programmable logic gate and routing method

    NASA Technical Reports Server (NTRS)

    Fijany, Amir (Inventor); Vatan, Farrokh (Inventor); Akarvardar, Kerem (Inventor); Blalock, Benjamin (Inventor); Chen, Suheng (Inventor); Cristoloveanu, Sorin (Inventor); Kolawa, Elzbieta (Inventor); Mojarradi, Mohammad M. (Inventor); Toomarian, Nikzad (Inventor)

    2009-01-01

    An universal and programmable logic gate based on G.sup.4-FET technology is disclosed, leading to the design of more efficient logic circuits. A new full adder design based on the G.sup.4-FET is also presented. The G.sup.4-FET can also function as a unique router device offering coplanar crossing of signal paths that are isolated and perpendicular to one another. This has the potential of overcoming major limitations in VLSI design where complex interconnection schemes have become increasingly problematic.

  19. Detector for flow abnormalities in gaseous diffusion plant compressors

    DOEpatents

    Smith, Stephen F.; Castleberry, Kim N.

    1998-01-01

    A detector detects a flow abnormality in a plant compressor which outputs a motor current signal. The detector includes a demodulator/lowpass filter demodulating and filtering the motor current signal producing a demodulated signal, and first, second, third and fourth bandpass filters connected to the demodulator/lowpass filter, and filtering the demodulated signal in accordance with first, second, third and fourth bandpass frequencies generating first, second, third and fourth filtered signals having first, second, third and fourth amplitudes. The detector also includes first, second, third and fourth amplitude detectors connected to the first, second, third and fourth bandpass filters respectively, and detecting the first, second, third and fourth amplitudes, and first and second adders connected to the first and fourth amplitude detectors and the second and third amplitude detectors respectively, and adding the first and fourth amplitudes and the second and third amplitudes respectively generating first and second added signals. Finally, the detector includes a comparator, connected to the first and second adders, and comparing the first and second added signals and detecting the abnormal condition in the plant compressor when the second added signal exceeds the first added signal by a predetermined value.

  20. Reliable circuit analysis and design using nanoscale devices

    NASA Astrophysics Data System (ADS)

    Kumawat, Renu; Sahula, Vineet; Gaur, M. S.

    2013-01-01

    The miniaturization of the devices into nanoscale has enabled ultra high density chips, but at the cost of increased defect density. In this manuscript, Markov Random Field (MRF) approach is used to evaluate the device reliability in the presence of high defect density. Both hard and soft errors have been considered. We have presented a NANOLAB based fault model of 8-bit full adder, basic building block being 2:1 multiplexer. At each level, a Triple Modular Redundancy (TMR) is employed to enhance reliability. The results are compared with another 8-bit full adder, designed using logic gates. Assuming defect rate up to 10%, the circuits are evaluated for stuck at faults. Further, we have augmented the NANOLAB tool to include a design library of various types of flip flops. A 4-bit SISO right shift register is used as vehicle for exemplifying our approach. The fault tolerant approach N-Modular Redundancy (NMR) is compared at different levels of granularity and for varying levels of N. It is observed that NMR fails to provide the device fault tolerance when defect rate is higher than a threshold value.

  1. Application of Magnetically Insulated Transmission Lines for high current, high voltage electron beam accelerators

    SciTech Connect

    Shope, S.L.; Mazarakis, M.G.; Frost, C.A.; Poukey, J.W.; Turman, B.N.

    1991-01-01

    Self Magnetically Insulated Transmission Lines (MITL) adders have been used successfully in a number of Sandia accelerators such as HELIA, HERMES III, and SABRE. Most recently we used at MITL adder in the RADLAC/SMILE electron beam accelerator to produce high quality, small radius (r{sub {rho}} < 2 cm), 11 to 15 MeV, 50 to 100-kA beams with a small transverse velocity v{perpendicular}/c = {beta}{perpendicular} {le} 0.1. In RADLAC/SMILE, a coaxial MITL passed through the eight, 2 MV vacuum envelopes. The MITL summed the voltages of all eight feeds to a single foilless diode. The experimental results are in good agreement with code simulations. Our success with the MITL technology led us to investigate the application to higher energy accelerator designs. We have a conceptual design for a cavity-fed MITL that sums the voltages from 100 identical, inductively-isolated cavities. Each cavity is a toroidal structure that is driven simultaneously by four 8-ohm pulse-forming lines, providing a 1-MV voltage pulse to each of the 100 cavities. The point design accelerator is 100 MV, 500 kA, with a 30--50 ns FWHM output pulse. 10 refs.

  2. Application of Magnetically Insulated Transmission Lines for high current, high voltage electron beam accelerators

    SciTech Connect

    Shope, S.L.; Mazarakis, M.G.; Frost, C.A.; Poukey, J.W.; Turman, B.N.

    1991-12-31

    Self Magnetically Insulated Transmission Lines (MITL) adders have been used successfully in a number of Sandia accelerators such as HELIA, HERMES III, and SABRE. Most recently we used at MITL adder in the RADLAC/SMILE electron beam accelerator to produce high quality, small radius (r{sub {rho}} < 2 cm), 11 to 15 MeV, 50 to 100-kA beams with a small transverse velocity v{perpendicular}/c = {beta}{perpendicular} {le} 0.1. In RADLAC/SMILE, a coaxial MITL passed through the eight, 2 MV vacuum envelopes. The MITL summed the voltages of all eight feeds to a single foilless diode. The experimental results are in good agreement with code simulations. Our success with the MITL technology led us to investigate the application to higher energy accelerator designs. We have a conceptual design for a cavity-fed MITL that sums the voltages from 100 identical, inductively-isolated cavities. Each cavity is a toroidal structure that is driven simultaneously by four 8-ohm pulse-forming lines, providing a 1-MV voltage pulse to each of the 100 cavities. The point design accelerator is 100 MV, 500 kA, with a 30--50 ns FWHM output pulse. 10 refs.

  3. A mechanistic stochastic framework for regulating bacterial cell division

    PubMed Central

    Ghusinga, Khem Raj; Vargas-Garcia, Cesar A.; Singh, Abhyudai

    2016-01-01

    How exponentially growing cells maintain size homeostasis is an important fundamental problem. Recent single-cell studies in prokaryotes have uncovered the adder principle, where cells add a fixed size (volume) from birth to division, irrespective of their size at birth. To mechanistically explain the adder principle, we consider a timekeeper protein that begins to get stochastically expressed after cell birth at a rate proportional to the volume. Cell-division time is formulated as the first-passage time for protein copy numbers to hit a fixed threshold. Consistent with data, the model predicts that the noise in division timing increases with size at birth. Intriguingly, our results show that the distribution of the volume added between successive cell-division events is independent of the newborn cell size. This was dramatically seen in experimental studies, where histograms of the added volume corresponding to different newborn sizes collapsed on top of each other. The model provides further insights consistent with experimental observations: the distribution of the added volume when scaled by its mean becomes invariant of the growth rate. In summary, our simple yet elegant model explains key experimental findings and suggests a mechanism for regulating both the mean and fluctuations in cell-division timing for controlling size. PMID:27456660

  4. Hardware Implementation of 32-Bit High-Speed Direct Digital Frequency Synthesizer

    PubMed Central

    Ibrahim, Salah Hasan; Ali, Sawal Hamid Md.; Islam, Md. Shabiul

    2014-01-01

    The design and implementation of a high-speed direct digital frequency synthesizer are presented. A modified Brent-Kung parallel adder is combined with pipelining technique to improve the speed of the system. A gated clock technique is proposed to reduce the number of registers in the phase accumulator design. The quarter wave symmetry technique is used to store only one quarter of the sine wave. The ROM lookup table (LUT) is partitioned into three 4-bit sub-ROMs based on angular decomposition technique and trigonometric identity. Exploiting the advantages of sine-cosine symmetrical attributes together with XOR logic gates, one sub-ROM block can be removed from the design. These techniques, compressed the ROM into 368 bits. The ROM compressed ratio is 534.2 : 1, with only two adders, two multipliers, and XOR-gates with high frequency resolution of 0.029 Hz. These techniques make the direct digital frequency synthesizer an attractive candidate for wireless communication applications. PMID:24991635

  5. The effect of CO2 regulations on the cost of corn ethanol production

    NASA Astrophysics Data System (ADS)

    Plevin, R. J.; Mueller, S.

    2008-04-01

    To explore the effect of CO2 price on the effective cost of ethanol production we have developed a model that integrates financial and emissions accounting for dry-mill corn ethanol plants. Three policy options are modeled: (1) a charge per unit of life cycle CO2 emissions, (2) a charge per unit of direct biorefinery emissions only, and (3) a low carbon fuel standard (LCFS). A CO2 charge on life cycle emissions increases production costs by between 0.005 and 0.008 l-1 per 10 Mg-1 CO2 price increment, across all modeled plant energy systems, with increases under direct emissions somewhat lower in all cases. In contrast, a LCFS increases the cost of production for selected plant energy systems only: a LCFS requiring reductions in average fuel global warming intensity (GWI) with a target of 10% below the 2005 baseline increases the production costs for coal-fired plants only. For all other plant types, the LCFS operates as a subsidy. The findings depend strongly on the magnitude of a land use change adder. Some land use change adders currently discussed in the literature will push the GWI of all modeled production systems above the LCFS target, flipping the CO2 price from a subsidy to a tax.

  6. Automatic oscillator frequency control system

    NASA Technical Reports Server (NTRS)

    Smith, S. F. (Inventor)

    1985-01-01

    A frequency control system makes an initial correction of the frequency of its own timing circuit after comparison against a frequency of known accuracy and then sequentially checks and corrects the frequencies of several voltage controlled local oscillator circuits. The timing circuit initiates the machine cycles of a central processing unit which applies a frequency index to an input register in a modulo-sum frequency divider stage and enables a multiplexer to clock an accumulator register in the divider stage with a cyclical signal derived from the oscillator circuit being checked. Upon expiration of the interval, the processing unit compares the remainder held as the contents of the accumulator against a stored zero error constant and applies an appropriate correction word to a correction stage to shift the frequency of the oscillator being checked. A signal from the accumulator register may be used to drive a phase plane ROM and, with periodic shifts in the applied frequency index, to provide frequency shift keying of the resultant output signal. Interposition of a phase adder between the accumulator register and phase plane ROM permits phase shift keying of the output signal by periodic variation in the value of a phase index applied to one input of the phase adder.

  7. The Probabilistic Convolution Tree: Efficient Exact Bayesian Inference for Faster LC-MS/MS Protein Inference

    PubMed Central

    Serang, Oliver

    2014-01-01

    Exact Bayesian inference can sometimes be performed efficiently for special cases where a function has commutative and associative symmetry of its inputs (called “causal independence”). For this reason, it is desirable to exploit such symmetry on big data sets. Here we present a method to exploit a general form of this symmetry on probabilistic adder nodes by transforming those probabilistic adder nodes into a probabilistic convolution tree with which dynamic programming computes exact probabilities. A substantial speedup is demonstrated using an illustration example that can arise when identifying splice forms with bottom-up mass spectrometry-based proteomics. On this example, even state-of-the-art exact inference algorithms require a runtime more than exponential in the number of splice forms considered. By using the probabilistic convolution tree, we reduce the runtime to and the space to where is the number of variables joined by an additive or cardinal operator. This approach, which can also be used with junction tree inference, is applicable to graphs with arbitrary dependency on counting variables or cardinalities and can be used on diverse problems and fields like forward error correcting codes, elemental decomposition, and spectral demixing. The approach also trivially generalizes to multiple dimensions. PMID:24626234

  8. Experimental validation of the nerve conduction velocity selective recording technique using a multi-contact cuff electrode.

    PubMed

    Yoshida, K; Kurstjens, G A M; Hennings, K

    2009-12-01

    The earthworm (Lumbricus terrestris) is presented as an in vitro model of a peripheral nerve containing only two fibers each with distinctly different conduction velocities, the median and lateral giant fibers (MGF and LGF). The worm model is used with a multi-contact cuff electrode to validate the spatial-temporal filtering effect of different electrode contact configurations and the effect of applying a delay adder and matched filter tuned to either the MGF or LGF action potential (AP) to extract conduction direction and velocity from the recording. The results confirmed the known effect of inter-electrode spacing and bipolar and tripolar recording configuration on the AP amplitude. It also demonstrates a crossover point where the amplitude of the tripolar recording is larger than the monopolar recording, an effect of the slower action potential conduction velocities in the worm. The delay adder was found to be an effective velocity sensitive filter, able to discriminate units based on conduction velocity. The matched filter to be an effective means to eliminate artifact and increase signal to noise ratios, however was not found to improve selectivity. PMID:19762269

  9. Detector for flow abnormalities in gaseous diffusion plant compressors

    DOEpatents

    Smith, S.F.; Castleberry, K.N.

    1998-06-16

    A detector detects a flow abnormality in a plant compressor which outputs a motor current signal. The detector includes a demodulator/lowpass filter demodulating and filtering the motor current signal producing a demodulated signal, and first, second, third and fourth bandpass filters connected to the demodulator/lowpass filter, and filtering the demodulated signal in accordance with first, second, third and fourth bandpass frequencies generating first, second, third and fourth filtered signals having first, second, third and fourth amplitudes. The detector also includes first, second, third and fourth amplitude detectors connected to the first, second, third and fourth bandpass filters respectively, and detecting the first, second, third and fourth amplitudes, and first and second adders connected to the first and fourth amplitude detectors and the second and third amplitude detectors respectively, and adding the first and fourth amplitudes and the second and third amplitudes respectively generating first and second added signals. Finally, the detector includes a comparator, connected to the first and second adders, and comparing the first and second added signals and detecting the abnormal condition in the plant compressor when the second added signal exceeds the first added signal by a predetermined value. 6 figs.

  10. Back-streaming ion beam measurements in a Self Magnetic Insulated (SMP) electron diode

    NASA Astrophysics Data System (ADS)

    Mazarakis, Michael; Johnston, Mark; Kiefer, Mark; Leckbee, Josh; Webb, Timothy; Bennett, Nichelle; Droemer, Darryl; Welch, Dale; Nielsen, Dan; Ziska, Derek; Wilkins, Frank; Advance radiography department Team

    2014-10-01

    A self-magnetic pinch diode (SMP) is presently the electron diode of choice for high energy flash x-ray radiography utilizing pulsed power drivers. The Sandia National Laboratories RITS accelerator is presently fit with an SMP diode that generates very small electron beam spots. RITS is a Self-Magnetically Insulated Transmission Line (MITL) voltage adder that adds the voltage pulse of six 1.3 MV inductively insulated cavities. The diode's anode is made of high Z metal in order to produce copious and energetic flash x-rays for radiographic imaging of high areal density objects. In any high voltage inductive voltage adder (IVA) utilizing MITLs to transmit the power to the diode load, the precise knowledge of the accelerating voltage applied on the anode-cathode (A-K) gap is problematic. This is even more difficult in an SMP diode where the A-K gap is very small (~1 cm) and the diode region very hostile. We are currently measuring the back-streaming ion currents emitted from the anode and propagating through a hollow cathode tip. We then are evaluating the A-K gap voltage by ion time of flight measurements supplemented with filtered Rogowski coils. Sandia is a multiprogram laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Company, for the United States Department of Energy's National Nuclear Security Administration under Contract No. DE- AC04-94AL850.

  11. Power flow in long MITLs with high-inductance loads

    SciTech Connect

    Poukey, J.W.; Mazarkis, M.G.

    1994-12-31

    The authors are using the 2-D TWOQUICK simulation code to study a system consisting of a voltage adder, a long magnetically-insulated transmission line (MITL), and a large-inductance load which includes a conducting foil (short circuit). The object of this work is to produce a voltage pulse of typically 10 MV and several hundred ns which travels down a MITL of about 10 meters length and 5--10 ohms vacuum impedance, and then couples efficiently to a load of a few hundred nH inductance. They discuss modeling issues such as the use of simple transmission lines for parts of the system, and methods for representing the load. Important physics issues include voltage-pulse erosion in long MITLs, effects of reflected waves from the highly overmatched load impedance, and energy fraction delivered to the load. They calculate electron losses in all parts of the system. Parameter variations of interest include input voltage waveform, adder geometry, MITL length and impedance, and loaded configuration and inductance. Comparisons with circuit models (SCREAMER) will be shown.

  12. A mechanistic stochastic framework for regulating bacterial cell division.

    PubMed

    Ghusinga, Khem Raj; Vargas-Garcia, Cesar A; Singh, Abhyudai

    2016-01-01

    How exponentially growing cells maintain size homeostasis is an important fundamental problem. Recent single-cell studies in prokaryotes have uncovered the adder principle, where cells add a fixed size (volume) from birth to division, irrespective of their size at birth. To mechanistically explain the adder principle, we consider a timekeeper protein that begins to get stochastically expressed after cell birth at a rate proportional to the volume. Cell-division time is formulated as the first-passage time for protein copy numbers to hit a fixed threshold. Consistent with data, the model predicts that the noise in division timing increases with size at birth. Intriguingly, our results show that the distribution of the volume added between successive cell-division events is independent of the newborn cell size. This was dramatically seen in experimental studies, where histograms of the added volume corresponding to different newborn sizes collapsed on top of each other. The model provides further insights consistent with experimental observations: the distribution of the added volume when scaled by its mean becomes invariant of the growth rate. In summary, our simple yet elegant model explains key experimental findings and suggests a mechanism for regulating both the mean and fluctuations in cell-division timing for controlling size. PMID:27456660

  13. Slime mould logic gates based on frequency changes of electrical potential oscillation.

    PubMed

    Whiting, James G H; de Lacy Costello, Ben P J; Adamatzky, Andrew

    2014-10-01

    Physarum polycephalum is a large single amoeba cell, which in its plasmodial phase, forages and connects nearby food sources with protoplasmic tubes. The organism forages for food by growing these tubes towards detected foodstuff, this foraging behaviour is governed by simple rules of photoavoidance and chemotaxis. The electrical activity of the tubes oscillates, creating a peristaltic like action within the tubes, forcing cytoplasm along the lumen; the frequency of this oscillation controls the speed and direction of growth. External stimuli such as light and food cause changes in the oscillation frequency. We demonstrate that using these stimuli as logical inputs we can approximate logic gates using these tubes and derive combinational logic circuits by cascading the gates, with software analysis providing the output of each gate and determining the input of the following gate. Basic gates OR, AND and NOT were correct 90%, 77.8% and 91.7% of the time respectively. Derived logic circuits XOR, half adder and full adder were 70.8%, 65% and 58.8% accurate respectively. Accuracy of the combinational logic decreases as the number of gates is increased, however they are at least as accurate as previous logic approximations using spatial growth of P. polycephalum and up to 30 times as fast at computing the logical output. The results shown here demonstrate a significant advancement in organism-based computing, providing a solid basis for hybrid computers of the future.

  14. Hardware implementation of 32-bit high-speed direct digital frequency synthesizer.

    PubMed

    Ibrahim, Salah Hasan; Ali, Sawal Hamid Md; Islam, Md Shabiul

    2014-01-01

    The design and implementation of a high-speed direct digital frequency synthesizer are presented. A modified Brent-Kung parallel adder is combined with pipelining technique to improve the speed of the system. A gated clock technique is proposed to reduce the number of registers in the phase accumulator design. The quarter wave symmetry technique is used to store only one quarter of the sine wave. The ROM lookup table (LUT) is partitioned into three 4-bit sub-ROMs based on angular decomposition technique and trigonometric identity. Exploiting the advantages of sine-cosine symmetrical attributes together with XOR logic gates, one sub-ROM block can be removed from the design. These techniques, compressed the ROM into 368 bits. The ROM compressed ratio is 534.2:1, with only two adders, two multipliers, and XOR-gates with high frequency resolution of 0.029 Hz. These techniques make the direct digital frequency synthesizer an attractive candidate for wireless communication applications.

  15. A mechanistic stochastic framework for regulating bacterial cell division.

    PubMed

    Ghusinga, Khem Raj; Vargas-Garcia, Cesar A; Singh, Abhyudai

    2016-07-26

    How exponentially growing cells maintain size homeostasis is an important fundamental problem. Recent single-cell studies in prokaryotes have uncovered the adder principle, where cells add a fixed size (volume) from birth to division, irrespective of their size at birth. To mechanistically explain the adder principle, we consider a timekeeper protein that begins to get stochastically expressed after cell birth at a rate proportional to the volume. Cell-division time is formulated as the first-passage time for protein copy numbers to hit a fixed threshold. Consistent with data, the model predicts that the noise in division timing increases with size at birth. Intriguingly, our results show that the distribution of the volume added between successive cell-division events is independent of the newborn cell size. This was dramatically seen in experimental studies, where histograms of the added volume corresponding to different newborn sizes collapsed on top of each other. The model provides further insights consistent with experimental observations: the distribution of the added volume when scaled by its mean becomes invariant of the growth rate. In summary, our simple yet elegant model explains key experimental findings and suggests a mechanism for regulating both the mean and fluctuations in cell-division timing for controlling size.

  16. Initial results from the unipolar operation of the RHEPP module

    SciTech Connect

    Harjes, H.C.; Penn, K.J.; Reed, K.W.; McClenahan, C.R.; Laderach, G.E.; Wavrik, R.W.; Adcock, J.L.; Butler, M.E.; Mann, G.A.; Pena, G.E.; Weber, G.J.; VanDeValde, D.; Martinez, L.E.; Muirhead, D.; Kiekel, P.D.; Johnson, D.L.; Neau, E.L.

    1992-01-01

    Several potential applications such as medical waste treatment, chemical waste treatment, food treatment, and flue gas cleanup have been identified for high average power electron beam systems. The technology for such a system is being developed in the RHEPP (Repetitive High Energy Pulsed Power) project. The RHEPP module consists of a multistage magnetic pulse compressor driving a linear induction voltage adder with an e-beam diode load. It has been designed to operate continuously, delivering 350 kW of average power to the diode in 60-ns FWHM, 2.5-MV, 2.9-kJ pulses. The module is presently under construction with the first phase scheduled for completion in the summer of 1992. In the first phase, four of ten adder stages are being built so that testing can begin with a I-MV, 160-kW diode with the balance of the power from the compressor diverted to a resistive load. A description of the system and test results from the initial stages of the compressor will be presented.

  17. Initial results from the unipolar operation of the RHEPP module

    SciTech Connect

    Harjes, H.C.; Penn, K.J.; Reed, K.W.; McClenahan, C.R.; Laderach, G.E.; Wavrik, R.W.; Adcock, J.L.; Butler, M.E.; Mann, G.A.; Pena, G.E.; Weber, G.J.; VanDeValde, D.; Martinez, L.E.; Muirhead, D.; Kiekel, P.D.; Johnson, D.L.; Neau, E.L.

    1992-08-01

    Several potential applications such as medical waste treatment, chemical waste treatment, food treatment, and flue gas cleanup have been identified for high average power electron beam systems. The technology for such a system is being developed in the RHEPP (Repetitive High Energy Pulsed Power) project. The RHEPP module consists of a multistage magnetic pulse compressor driving a linear induction voltage adder with an e-beam diode load. It has been designed to operate continuously, delivering 350 kW of average power to the diode in 60-ns FWHM, 2.5-MV, 2.9-kJ pulses. The module is presently under construction with the first phase scheduled for completion in the summer of 1992. In the first phase, four of ten adder stages are being built so that testing can begin with a I-MV, 160-kW diode with the balance of the power from the compressor diverted to a resistive load. A description of the system and test results from the initial stages of the compressor will be presented.

  18. Complementary code and digital filtering for detection of weak VHF radar signals from the mesoscale. [SOUSY-VHF radar, Harz Mountains, Germany

    NASA Technical Reports Server (NTRS)

    Schmidt, G.; Ruster, R.; Czechowsky, P.

    1983-01-01

    The SOUSY-VHF-Radar operates at a frequency of 53.5 MHz in a valley in the Harz mountains, Germany, 90 km from Hanover. The radar controller, which is programmed by a 16-bit computer holds 1024 program steps in core and controls, via 8 channels, the whole radar system: in particular the master oscillator, the transmitter, the transmit-receive-switch, the receiver, the analog to digital converter, and the hardware adder. The high-sensitivity receiver has a dynamic range of 70 dB and a video bandwidth of 1 MHz. Phase coding schemes are applied, in particular for investigations at mesospheric heights, in order to carry out measurements with the maximum duty cycle and the maximum height resolution. The computer takes the data from the adder to store it in magnetic tape or disc. The radar controller is programmed by the computer using simple FORTRAN IV statements. After the program has been loaded and the computer has started the radar controller, it runs automatically, stopping at the program end. In case of errors or failures occurring during the radar operation, the radar controller is shut off caused either by a safety circuit or by a power failure circuit or by a parity check system.

  19. Design and implementation of moment invariants for pattern recognition in VLSI

    NASA Astrophysics Data System (ADS)

    Armstrong, Gary A.; Simpson, Marc L.; Bouldin, Donald W.

    1990-09-01

    This paper describes the design of a very large scale integration (VLSI) application specific integrated circuit (ASIC) for use in pattern recognition. The pattern recognition scheme uses Hu1 and Mailra''s2 algorithms for moment invariants. A prototype design was generated that resolved the long delay time of the multiplier by custom designing adder cells based on the Manchester carry chain. Use of the Manchester carry chain effectively incorporated the lookahead carry function into the adder cells. The prototype ASIC is currently being fabricated in 2. 0-mm compiled simulator for metal oxide semiconductor (CMOS) technology (simulated at 20 MHz). The prototype consisted of a 4x8 multiplier and a 12-bit accumulator stage. The present ASIC design consists of a 9x26 multiplier (maximum propagation time of 50 ns) and a 48-bit accumulator stage. The final ASICs will be used in parallel at the board level to achieve the 56 MegaPixels/s [230 million operations per second (MOPs)] necessary to perform the moment invariant algorithms in real time on 512x512 pixel images with 256 grey scales. 2.

  20. Demonstration of optical computing logics based on binary decision diagram.

    PubMed

    Lin, Shiyun; Ishikawa, Yasuhiko; Wada, Kazumi

    2012-01-16

    Optical circuits are low power consumption and fast speed alternatives for the current information processing based on transistor circuits. However, because of no transistor function available in optics, the architecture for optical computing should be chosen that optics prefers. One of which is Binary Decision Diagram (BDD), where signal is processed by sending an optical signal from the root through a serial of switching nodes to the leaf (terminal). Speed of optical computing is limited by either transmission time of optical signals from the root to the leaf or switching time of a node. We have designed and experimentally demonstrated 1-bit and 2-bit adders based on the BDD architecture. The switching nodes are silicon ring resonators with a modulation depth of 10 dB and the states are changed by the plasma dispersion effect. The quality, Q of the rings designed is 1500, which allows fast transmission of signal, e.g., 1.3 ps calculated by a photon escaping time. A total processing time is thus analyzed to be ~9 ps for a 2-bit adder and would scales linearly with the number of bit. It is two orders of magnitude faster than the conventional CMOS circuitry, ~ns scale of delay. The presented results show the potential of fast speed optical computing circuits.

  1. Alleviation of viper venom induced platelet apoptosis by crocin (Crocus sativus): implications for thrombocytopenia in viper bites.

    PubMed

    Santhosh, M Sebastin; Thushara, R M; Hemshekhar, M; Sunitha, K; Devaraja, S; Kemparaju, K; Girish, K S

    2013-11-01

    Viper envenomations are characterized by prominent local and systemic manifestations including hematological alterations. Snake venom metalloproteinases (SVMPs) and phospholipase A2 (PLA2) plays crucial role in the pathophysiology of hemorrhage by targeting/altering the platelets function which may result in thrombocytopenia. Platelets undergo the classic events of mitochondria-mediated apoptotic pathway due to augmented endogenous reactive oxygen species (ROS) levels. The observed anticoagulant effects during viper envenomations could be due to exacerbated platelet apoptosis and thrombocytopenia. Moreover, antivenin treatments are ineffective against the venom-induced oxidative stress; therefore, it necessitates an auxiliary therapy involving antioxidants which can effectively scavenge the endothelium-generated/endogenous ROS and protect the platelets. The present study explored the effects of viper venom on platelet apoptosis and its amelioration by a phytochemical crocin. The study evaluated the Vipera russelli venom-induced apoptotic events including endogenous ROS generation, intracellular Ca(2+) mobilization, mitochondrial membrane depolarization, cyt-c translocation, caspase activation and phosphatidylserine externalization which were effectively mitigated when the venom was pre-treated with crocin. The study highlights one of the less studied features of venom-induced secondary complications i.e. platelet apoptosis and sheds light on the underlying basis for venom-induced thrombocytopenia, systemic hemorrhage and in vivo anticoagulant effect.

  2. Interactions of pharmacologically active snake venom sPLA2 with different cell lines

    PubMed Central

    Doumanov, Jordan; Mladenova, Kirilka; Aleksandrov, Radoslav; Danovski, Georgi; Petrova, Svetla

    2014-01-01

    Secreted Phospholipases A2 (sPLA2s) represent a large family of structurally related enzymes, which target different tissues and organs and induce numerous pharmacological effects based on their catalytic specificity – hydrolysis of the sn-2 ester bond of glycerophospholipids. The neurotoxin vipoxin, isolated from the venom of Vipera ammodytes meriodionalis, is a heterodimeric postsynaptic ionic complex composed of two protein subunits – a basic and toxic His48 sPLA2 enzyme and an acidic, enzymatically inactive and non-toxic component. In this paper, for the first time, we demonstrate that vipoxin sPLA2 enzyme affects cell integrity and viability of four cell types and causes different cell responses. The most dramatic local tissue effects were observed with RPE-1 (retinal pigment epithelial) cells followed by A549 (adenocarcinomic human alveolar epithelial) cells and MDCK (Madin-Darby Canine Kidney epithelial) cells. Products of the enzymatic reaction, lysophospholipids and unsaturated free fatty acids, act as lipid mediators that can induce membrane damaging or can stimulate cell proliferation. Our preliminary results on the cytotoxic effect of vipoxin sPLA2 on A549 cells are promising in searching of its eventual anticancer potential. PMID:26019578

  3. Sex-specific fitness returns are too weak to select for non-random patterns of sex allocation in a viviparous snake.

    PubMed

    Baron, Jean-Pierre; Tully, Thomas; Le Galliard, Jean-François

    2010-10-01

    When environmental conditions exert sex-specific selection on offspring, mothers should benefit from biasing their sex allocation towards the sex with the highest fitness in a given environment. Yet, studies show mixed support for such adaptive strategies in vertebrates, which may be due to mechanistic constraints and/or weak selection on facultative sex allocation. In an attempt to disentangle these alternatives, we quantified sex-specific fitness returns and sex allocation (sex ratio and sex-specific mass at birth) according to maternal factors (body size, age, birth date, and litter size), habitat, and year in a viviparous snake with genotypic sex determination. We used data on 106 litters from 19 years of field survey in two nearby habitats occupied by the meadow viper Vipera ursinii ursinii in south-eastern France. Maternal reproductive investment and habitat quality had no differential effects on the growth and survival of sons and daughters. Sex ratio at birth was balanced despite a slight female-biased mortality before birth. No sexual mass dimorphism between offspring was evident. Sex allocation was almost random apart for a trend towards more male-biased litters as females grew older, which could be explained by an inbreeding avoidance strategy. Thus, a weak selection for facultative sex allocation seems sufficient to explain the almost equal sex allocation in the meadow viper.

  4. Structural and Pharmacological Comparison of Daboiatoxin from Badoia russelli siamensis with Viperotoxing F and Vipoxin from Other Vipers

    SciTech Connect

    Gopolan,G.; Thwin, M.; Gopalakrishnakone, P.; Swaminathan, K.

    2007-01-01

    Russell's viper (Vipera russelli, also known as Daboia russelli) is one of the major causes of fatal snakebites. To date, five Daboia russelli subspecies have been recognized. Daboiatoxin (DbTx) is the main lethal phospholipase A{sub 2} (PLA{sub 2}) toxin in the venom of D. russelli siamensis (Myanmar viper) and has strong neurotoxic, myotoxic and cytotoxic activities. DbTx and its homologous neurotoxins viperotoxin F from D. russelli formosensis (Taiwan viper) and vipoxin from the Bulgarian sand viper V. ammodytes meridionalis consist of complexes between a nontoxic acidic PLA2 protein and an enzymatically active basic PLA2. DbTx and viperotoxin F are presynaptic toxins, while vipoxin is postsynaptic. The two chains of DbTx have been separated and their PLA2 enzymatic activity has been measured using the secretory PLA2 assay kit. The enzymatic activity of DbTx chain B is reduced by 30% of its original activity by chain A in a unimolar ratio, thus indicating that DbTx chain A acts as an inhibitor. The lethal activity of the two chains has also been studied in male albino mice and chain A is less lethal than chain B. The crystal structure of DbTx has also been determined and its structural details are compared with those of the two homologues. Furthermore, an attempt is made to correlate the sequence and structural determinants of these toxins with their enzymatic activities and their pharmacological effects.

  5. Anti-cancer effect of snake venom toxin through down regulation of AP-1 mediated PRDX6 expression

    PubMed Central

    Son, Dong Ju; Song, Ho Sub; Kim, Jung Hyun; Ko, Seong Cheol; Song, Min Jong; Lee, Won Hyoung; Yoon, Joo Hee; Ham, Young Wan; Han, Sang Bae; Hong, Jin Tae

    2015-01-01

    Snake venom toxin (SVT) from Vipera lebetina turanica contains a mixture of different enzymes and proteins. Peroxiredoxin 6 (PRDX6) is known to be a stimulator of lung cancer cell growth. PRDX6 is a member of peroxidases, and has calcium-independent phospholipase A2 (iPLA2) activities. PRDX6 has an AP-1 binding site in its promoter region of the gene. Since AP-1 is implicated in tumor growth and PRDX6 expression, in the present study, we investigated whether SVT inhibits PRDX6, thereby preventing human lung cancer cell growth (A549 and NCI-H460) through inactivation of AP-1. A docking model study and pull down assay showed that SVT completely fits on the basic leucine zipper (bZIP) region of c-Fos of AP-1. SVT (0–10 μg/ml) inhibited lung cancer cell growth in a concentration dependent manner through induction of apoptotic cell death accompanied by induction of cleaved caspase-3, -8, -9, Bax, p21 and p53, but decreased cIAP and Bcl2 expression via inactivation of AP-1. In an xenograft in vivo model, SVT (0.5 mg/kg and 1 mg/kg) also inhibited tumor growth accompanied with the reduction of PRDX6 expression, but increased expression of proapoptotic proteins. These data indicate that SVT inhibits tumor growth via inhibition of PRDX6 activity through interaction with its transcription factor AP-1. PMID:26061816

  6. Correlations between benthic habitats and demersal fish assemblages — A case study on the Dogger Bank (North Sea)

    NASA Astrophysics Data System (ADS)

    Sell, Anne F.; Kröncke, Ingrid

    2013-07-01

    The interdependence between groundfish assemblages and habitat properties was investigated on the Dogger Bank in the North Sea. Abiotic habitat parameters considered included topography, hydrographic conditions, sediment composition, and the biotic habitat variable the prevailing benthic invertebrates. Distinct epi- and infauna communities occurred at different locations on the Dogger Bank. Fish assemblages were clearly linked to both the biotic and abiotic habitat characteristics. Overall, fish and benthic communities revealed similar spatial distribution, represented in the respective clusters of characteristic and abundant species. Distribution patterns corresponded with the prevailing abiotic conditions such as depth and sediment composition, which appear to relate to autecological preferences of individual species. The apparently most generalist species, grey gurnard (Eutrigla gurnardus) and dab (Limanda limanda) occurred at all stations and dominated in terms of biomass in most cases. The absolute numbers of grey gurnards were related to the abundance of suitable prey, invertebrate and fish species, which stomach analyses revealed as part of the diet in an independent study during the same research cruise. Haddock (Melanogrammus aeglefinus) and whiting (Merlangius merlangus) were only abundant at deep stations along the flanks of the bank. The occurrence of lemon sole (Microstomus kitt), American plaice (Hippoglossoides platessoides) and cod (Gadus morhua) was also positively correlated with depth, whereas especially lesser weever (Echiichthys vipera), sandeel species and solenette (Buglossidium luteum) occurred predominantly at the shallower sites. At the same time, individual fish species such as solenette and lesser weever were associated with high densities of selected epi- or infauna species.

  7. Parasite assemblages in the Western whip snake Hierophis viridiflavus carbonarius (Colubridae) from southern Italy.

    PubMed

    Santoro, M; Aznar, F J; Mattiucci, S; Kinsella, J M; Pellegrino, F; Cipriani, P; Nascetti, G

    2013-09-01

    Parasite assemblages of the Western whip snake Hierophis viridiflavus carbonarius were investigated from the Calabria region in southern Italy. A total of 14 parasite taxa including 6 nematodes, 3 acanthocephalans, 2 cestodes, 2 digeneans and a single pentastomid was identified. Within the study area, H. v. carbonarius serves as the final host for seven species of helminths, of which only four (Hexametra quadricornis, Kalicephalus viperae, Paracapillaria sonsinoi and Renifer aniarum) can be considered as snake specialists, while one (Oswaldocruzia filiformis) is shared with other reptiles and amphibians, and two (Paradistomum mutabile and Rhabdias fuscovenosa) with lizards. A large proportion of larval forms of six helminth taxa (about 95% of all helminths collected) was found, for which H. v. carbonarius serves as an intermediate and/or paratenic host; however, adult stages of helminths were prevalent in snakes with snout-to-vent length greater than 70 cm. Our results suggest that ontogenetic and ecological factors should exert a strong influence upon the helminth assemblage of Western whip snakes. We concluded that H. v. carbonarius plays an important role in southern Italy as an intermediate/paratenic host for species of helminths infecting vertebrate groups which may include this snake species within their feeding chain. Eleven taxa, including three potential agents of zoonosis, were added to the poorly known parasite fauna of this host. PMID:22691545

  8. Long term variations in small mammal composition of a snake diet do not mirror climate change trends

    NASA Astrophysics Data System (ADS)

    Rugiero, Lorenzo; Milana, Giuliano; Capula, Massimo; Amori, Giovanni; Luiselli, Luca

    2012-08-01

    The study of the dietary changes which have intervened over the years in generalist and opportunist predators may provide useful information on the temporal modifications of their prey communities, especially under a climate change scenario. In this study, we analysed the quantitative changes in the small mammal portion of the diet of a generalist and opportunist predator, the asp viper (Vipera aspis) at a forest zone in central Italy, for the period 1987-2010. In addition, small mammals were trapped in five of these years. Apodemus spp., Mus musculus, and Myodes glareolus were the main prey for vipers. Among the various taxa eaten by vipers, only two showed significantly consistent trends over the years, with M. glareolus increasing and Sorex spp. declining in the viper diet. There were no significant relationships between the number of years passed after the first year of sampling and the diversity and dominance indexes of prey composition. We also found a significantly positive relationship between small mammal abundance in the field and their relative frequency of occurrence in the viper's diet, thus demonstrating that vipers really sampled the small mammal species in relation to their local availability. Despite being temperate-zone forest-associated species, hence likely adversed by global warming, Sorex spp. and M. glareolus showed opposite trends over the years, thus suggesting that such trends may reflect more local scale perturbations (local forest overgrowth and diminution of logging).

  9. Energy and delay trade-offs in arithmetic circuits: Methodologies and optimizations

    NASA Astrophysics Data System (ADS)

    Baran, Dursun

    Technology scaling cannot provide sufficient amount of energy reduction to keep control of the energy consumption of the current VLSI systems. In order to solve the problem of the high power dissipation of current processors, a complete optimization framework is developed. The system architecture, circuit topology, gate sizes and the technology related parameters are optimized jointly. For this purpose, circuit design methodologies are developed for demanded applications. The developed circuit design techniques target two objectives namely critical path complexity reduction of the circuit and the equalization of the signal path complexities. The generated circuit topologies are candidates for the energy efficient design. The final determination of the best circuit topology is made after optimizing the gate sizes and the voltage supply of the design. For this purpose, a quick circuit sizing algorithm (Constant Stage Effort Ratio) is developed. The algorithm redistributes the effort delay through the circuit to reduce the energy consumption at the same performance. The run-time of the developed algorithm linearly depends on the number of the logic gates in the circuit. By using the developed algorithm, a considerable amount of the run-time improvement is obtained. The developed optimization framework is applied to the parallel prefix adders and parallel multipliers. Up to 4.5X energy saving is obtained by the use of the design methodologies in 64-bit parallel adders over existing designs. Energy-efficient parallel adder structures are developed for static, domino and compound domino logic families. The suitability of the developed design techniques are explored in future technology nodes as well. Similar analysis is performed to the parallel multipliers. 16x16-bit serial, single-cycle parallel and two-cycle parallel multiplier structures are optimized using the developed optimization flow. Up to 20% energy reduction is obtained in static single-cycle 16x16-bit

  10. Ka-Band Wide-Bandgap Solid-State Power Amplifier: Prototype Combiner Spurious Mode Suppression and Power Constraints

    NASA Technical Reports Server (NTRS)

    Khan, P.; Epp, L.

    2006-01-01

    Results of prototype hardware activities related to a 120-W, 32-GHz (Ka-band) solid-state power amplifier (SSPA) architecture study are presented. Spurious mode suppression and the power-handling capability of a prototype 24-way radial combiner and a prototype 2-way septum binary combiner were investigated. Experimental data indicate that a commercial absorptive filter, designed to pass the circular TE01 mode, effectively suppressed the higher-order modes generated by a narrowband, flower-petal-type mode transducer. However, the same filter was not effective in suppressing higher-order modes generated by the broadband Marie mode transducer that is used in the prototype waveguide radial combiner. Should greater filtering be required by a particular SSPA application, a broadband mode filter that can suppress specifically those higher-order modes that are generated by the Marie transducer will need to be developed. A back-to-back configuration of the prototype radial combiner was tested with drive power up to approximately 50 W. No anomalous behavior was observed. Power measurements of the septum combiner indicate that up to 10-W radio frequency (RF) can be dissipated in the integrated resistive element before a permanent performance shift is observed. Thus, a given adder (a single-stage, 2-way combiner) can safely combine two 20-W sources, and the adder will not be damaged in the event of a source failure. This result is used to calculate the maximum source power that can be safely combined as a function of the number of sources combined and the number of source failures allowed in a multi-stage combiner. The analysis shows that SSPA power >140 W can be generated by power combining 16 sources producing 10 W each. In this configuration, up to three sources could fail with the guarantee that the combiner would not be damaged. Finally, a modified prototype septum combiner design was verified. The improved design reduced the assembly time from over 2 hours to about 15

  11. An Approach for Self-Timed Synchronous CMOS Circuit Design

    NASA Technical Reports Server (NTRS)

    Walker, Alvernon; Lala, Parag K.

    2001-01-01

    In this letter we present a timing and control strategy that can be used to realize synchronous systems with a level of performance that approaches that of asynchronous circuits or systems. This approach is based upon a single-phase synchronous circuit/system architecture with a variable period clock. The handshaking signals required for asynchronous self-timed circuits are not needed. Dynamic power supply current monitoring is used to generate the timing information, that is comparable to the completion signal found in self-timed circuits; this timing information is used to modi@ the circuit clock period. This letter is concluded with an example of the proposed approach applied to a static CMOS ripple-carry adder.

  12. Analog to digital converter for two-dimensional radiant energy array computers

    NASA Technical Reports Server (NTRS)

    Shaefer, D. H.; Strong, J. P., III (Inventor)

    1977-01-01

    The analog to digital converter stage derives a bit array of digital radiant energy signals representative of the amplitudes of an input radiant energy analog signal array and derives an output radiant energy analog signal array to serve as an input to succeeding stages. The converter stage includes a digital radiant energy array device which contains radiant energy array positions so that the analog array is less than a predetermined threshold level. A scaling device amplifies the radiant signal levels of the input array and the digital array so that the radiant energy signal level carried by the digital array corresponds to the threshold level. An adder device adds the signals of the scaled input and digital arrays at corresponding array positions to form the output analog array.

  13. Investigating digital optical computing with spatial light rebroadcasters

    NASA Astrophysics Data System (ADS)

    McAulay, Alastair D.; Wang, Junqing; Xu, Xin

    1991-10-01

    Spatial light rebroadcasters (SLR's) consisting of thin films of luminescing electron trapping materials, are explored for digital optical computing. The status of optical computing is reviewed briefly. SLR's are characterized in detail; fabrication, sensitivity, linearity, speed, resolution, and modulation. A number of optical experiments are described that were conducted to determine the device effectiveness, applications for which the devices are best suited, and the direction for research to develop more useful devices. Optical experiments with basic SLR modules include a cascadable module, binary matrix-vector multiplier, and correlator. The basic modules were then used in memory, adder, interconnection, and learning experiments. These experiments show that the SLR has potential for digital optical computing, particularly where high density long term storage is required. However, the lack of gain, incoherent output, and lot output signal means that other collaborative devices are needed which limit the performance. Future directions are discussed.

  14. Note: All-digital pulse-shrinking time-to-digital converter with improved dynamic range.

    PubMed

    Chen, Chun-Chi; Hwang, Chorng-Sii; Lin, Yi; Chen, Guan-Hong

    2016-04-01

    This paper proposes an all-digital pulse-shrinking time-to-digital converter (TDC) using the offset error cancellation circuitry to widen its dynamic range and to improve its accuracy. Although the TDC based on a pulse-shrinking mechanism can achieve a sub-gate resolution without circuit complexity, it possesses an undesired offset error that results in a nonzero lower bound appeared in its dynamic range and then affects its accuracy. The proposed cancellation circuitry for eliminating the offset error consists of a time adder with a delay line and a time subtractor with an identical delay line. The experimental TDC is implemented on Xilinx field programmable gate arrays and it also functions successfully in improving its dynamic range.

  15. Evolutionary Based Techniques for Fault Tolerant Field Programmable Gate Arrays

    NASA Technical Reports Server (NTRS)

    Larchev, Gregory V.; Lohn, Jason D.

    2006-01-01

    The use of SRAM-based Field Programmable Gate Arrays (FPGAs) is becoming more and more prevalent in space applications. Commercial-grade FPGAs are potentially susceptible to permanently debilitating Single-Event Latchups (SELs). Repair methods based on Evolutionary Algorithms may be applied to FPGA circuits to enable successful fault recovery. This paper presents the experimental results of applying such methods to repair four commonly used circuits (quadrature decoder, 3-by-3-bit multiplier, 3-by-3-bit adder, 440-7 decoder) into which a number of simulated faults have been introduced. The results suggest that evolutionary repair techniques can improve the process of fault recovery when used instead of or as a supplement to Triple Modular Redundancy (TMR), which is currently the predominant method for mitigating FPGA faults.

  16. Recent Advances in Photonic Devices for Optical Computing and the Role of Nonlinear Optics-Part II

    NASA Technical Reports Server (NTRS)

    Abdeldayem, Hossin; Frazier, Donald O.; Witherow, William K.; Banks, Curtis E.; Paley, Mark S.

    2007-01-01

    The twentieth century has been the era of semiconductor materials and electronic technology while this millennium is expected to be the age of photonic materials and all-optical technology. Optical technology has led to countless optical devices that have become indispensable in our daily lives in storage area networks, parallel processing, optical switches, all-optical data networks, holographic storage devices, and biometric devices at airports. This chapters intends to bring some awareness to the state-of-the-art of optical technologies, which have potential for optical computing and demonstrate the role of nonlinear optics in many of these components. Our intent, in this Chapter, is to present an overview of the current status of optical computing, and a brief evaluation of the recent advances and performance of the following key components necessary to build an optical computing system: all-optical logic gates, adders, optical processors, optical storage, holographic storage, optical interconnects, spatial light modulators and optical materials.

  17. 1D linear-phase band-pass multiplierless FIR Hilbert transformers and filters

    NASA Astrophysics Data System (ADS)

    Pavlović, Vlastimir D.; Dončov, Nebojša S.; Ćirić, Dejan G.

    2016-06-01

    An original analytical method, based on modified Christoffel-Darboux formula, is used in the paper in order to synthesise a linear-phase band-pass finite impulse response (FIR) filter function that can have an effect of Hilbert transformer. New structure of the band-pass FIR filter in recursive realisation, together with the corresponding difference equation, is presented providing the efficient filter solution without multipliers. Several examples of filter types for different parity of two real free integer parameters, including a particular solution of Hilbert transformer, are considered in terms of required number of adders and values of cut-off frequencies of the pass and stop bands. A comparison of the proposed band-pass filter characteristics with those of a classical filter solution is provided in the paper.

  18. Power optimization in logic isomers

    NASA Technical Reports Server (NTRS)

    Panwar, Ramesh; Rennels, David; Alkalaj, Leon

    1993-01-01

    Logic isomers are labeled, 2-isomorphic graphs that implement the same logic function. Logic isomers may have significantly different power requirements even though they have the same number of transistors in the implementation. The power requirements of the isomers depend on the transition activity of the input signals. The power requirements of isomorphic graph isomers of n-input NAND and NOR gates are shown. Choosing the less power-consuming isomer instead of the others can yield significant power savings. Experimental results on a ripple-carry adder are presented to show that the implementation using the least power-consuming isomers requires approximately 10 percent less power than the implementation using the most power-consuming isomers. Simulations of other random logic designs also confirm that designs using less power-consuming isomers can reduce the logic power demand by approximately 10 percent as compared to designs using more power-consuming isomers.

  19. The COBRA accelerator pulsed-power driver for Cornell/Sandia ICF research

    SciTech Connect

    Smith, D.L.; Ingwersen, P.; Bennett, L.F.; Boyes, J.D.; Anderson, D.E.; Greenly, J.B.; Sudan, R.N.; Hammer, D.A.

    1995-07-01

    This paper introduces and describes the new Cornell Beam Research Accelerator, COBRA, the result of a three and one-half year collaboration. The flexible 4 to 5-MV, 100 to 250-kA, 46-ns pulse width accelerator is based on a four-cavity Inductive Voltage Adder (IVA) design. In addition to being a mix of new and existing components, COBRA is unique in the sense that each cavity is driven by a single pulse forming line, and the IVA output polarity may be reversed by rotating the cavities 1800 about their vertical axis. Our tests with negative high voltage on the inner MITL stalk indicate that the vacuum power flow has established reasonable azimuthal symmetry within about 2 ns (or 0.6 m) after the cavity output cap. Preliminary results with the accelerator, single cavity, and MITL are presented alone, with the design details and circuit model predictions.

  20. Active Detection of Shielded Special Nuclear Material in the Presence of Variable High Backgrounds Using a Mixed Photon-Neutron Source

    NASA Astrophysics Data System (ADS)

    Martin, Philip N.; Clemett, Ceri D.; Hill, Cassie; O'Malley, John; Campbell, Ben

    This paper describes and compares two approaches to the analysis of active interrogation data containing high photon backgrounds associated with mixed photon-neutron source flash active interrogation. Results from liquid scintillation detectors (EJ301/EJ309) fielded at the Naval Research Laboratory (NRL), in collaboration with the Atomic Weapons Establishment (AWE), using the NRL Mercury Inductive Voltage Adder (IVA) operating in both a photon and mixed photon-neutron mode at a Depleted Uranium (DU) target are presented. The standard approach applying a Figure of Merit (FOM) consisting of background sigma above background is compared with an approach looking to fit only the time-decaying photon signal with standard delayed photon emission from ∼10-MeV end-point-energy Bremsstrahlung photofission of DU. Examples where each approach does well and less well are presented together with a discussion of the relative limitations of both approaches to the type of mixed photon-neutron flash active interrogation being considered.

  1. Design and implementation in VHDL code of the two-dimensional fast Fourier transform for frequency filtering, convolution and correlation operations

    NASA Astrophysics Data System (ADS)

    Vilardy, Juan M.; Giacometto, F.; Torres, C. O.; Mattos, L.

    2011-01-01

    The two-dimensional Fast Fourier Transform (FFT 2D) is an essential tool in the two-dimensional discrete signals analysis and processing, which allows developing a large number of applications. This article shows the description and synthesis in VHDL code of the FFT 2D with fixed point binary representation using the programming tool Simulink HDL Coder of Matlab; showing a quick and easy way to handle overflow, underflow and the creation registers, adders and multipliers of complex data in VHDL and as well as the generation of test bench for verification of the codes generated in the ModelSim tool. The main objective of development of the hardware architecture of the FFT 2D focuses on the subsequent completion of the following operations applied to images: frequency filtering, convolution and correlation. The description and synthesis of the hardware architecture uses the XC3S1200E family Spartan 3E FPGA from Xilinx Manufacturer.

  2. Integrated logic circuits using single-atom transistors.

    PubMed

    Mol, J A; Verduijn, J; Levine, R D; Remacle, F; Rogge, S

    2011-08-23

    Scaling down the size of computing circuits is about to reach the limitations imposed by the discrete atomic structure of matter. Reducing the power requirements and thereby dissipation of integrated circuits is also essential. New paradigms are needed to sustain the rate of progress that society has become used to. Single-atom transistors, SATs, cascaded in a circuit are proposed as a promising route that is compatible with existing technology. We demonstrate the use of quantum degrees of freedom to perform logic operations in a complementary-metal-oxide-semiconductor device. Each SAT performs multilevel logic by electrically addressing the electronic states of a dopant atom. A single electron transistor decodes the physical multivalued output into the conventional binary output. A robust scalable circuit of two concatenated full adders is reported, where by utilizing charge and quantum degrees of freedom, the functionality of the transistor is pushed far beyond that of a simple switch. PMID:21808050

  3. Note: A pulsed laser ion source for linear induction accelerators

    NASA Astrophysics Data System (ADS)

    Zhang, H.; Zhang, K.; Shen, Y.; Jiang, X.; Dong, P.; Liu, Y.; Wang, Y.; Chen, D.; Pan, H.; Wang, W.; Jiang, W.; Long, J.; Xia, L.; Shi, J.; Zhang, L.; Deng, J.

    2015-01-01

    We have developed a high-current laser ion source for induction accelerators. A copper target was irradiated by a frequency-quadrupled Nd:YAG laser (266 nm) with relatively low intensities of 108 W/cm2. The laser-produced plasma supplied a large number of Cu+ ions (˜1012 ions/pulse) during several microseconds. Emission spectra of the plasma were observed and the calculated electron temperature was about 1 eV. An induction voltage adder extracted high-current ion beams over 0.5 A/cm2 from a plasma-prefilled gap. The normalized beam emittance measured by a pepper-pot method was smaller than 1 π mm mrad.

  4. Virtual gap dielectric wall accelerator

    DOEpatents

    Caporaso, George James; Chen, Yu-Jiuan; Nelson, Scott; Sullivan, Jim; Hawkins, Steven A

    2013-11-05

    A virtual, moving accelerating gap is formed along an insulating tube in a dielectric wall accelerator (DWA) by locally controlling the conductivity of the tube. Localized voltage concentration is thus achieved by sequential activation of a variable resistive tube or stalk down the axis of an inductive voltage adder, producing a "virtual" traveling wave along the tube. The tube conductivity can be controlled at a desired location, which can be moved at a desired rate, by light illumination, or by photoconductive switches, or by other means. As a result, an impressed voltage along the tube appears predominantly over a local region, the virtual gap. By making the length of the tube large in comparison to the virtual gap length, the effective gain of the accelerator can be made very large.

  5. Designing of Low-Power VLSI Circuits using Non-Clocked Logic Style

    NASA Astrophysics Data System (ADS)

    Sharma, Vishal; Srivastava, Jitendra Kaushal

    2012-08-01

    Due to the trade-off between power, area and performance, various efforts have been done. This work is also based to reduce the power dissipation of the vlsi circuits with the performance upto the acceptable level. The dominant term in a well designed vlsi circuit is the switching power and low-power design thus becomes the task of minimizing this switching power. So, to design a low-power vlsi circuit, it is preferable to use Nonclocked logic styles as they have less switching power. In this work various Non-clocked logic styles are compared by performing transistor level simulations for half adder circuit using TSMC 0.18 µm Technology and Eldo simulator of Mentor graphics.

  6. Large capacity, high-speed multiparameter multichannel analysis system

    SciTech Connect

    Hendricks, R.W.; Seeger, P.A.; Scheer, J.W.; Suehiro, S.

    1980-01-01

    A data acquisition system for recording multiparameter digital data into a large memory array at over 2.5 MHz is described. The system consists of a MOSTEK MK8600 2048K x 24-bit memory system, I/O ports to various external devices including the CAMAC dataway, a memory incrementer/adder and a daisy-chain of experiment-specific modules which calculate the memory address which is to be incremented. The design of the daisy-chain permits multiple modules and provides for easy modification as experimental needs change. The system has been designed for use in multiparameter, multichannel analysis of high-speed data gathered by position-sensitive detectors at conventional and synchrotron x-ray sources as well as for fixed energy and time-of-flight diffraction at continuous and pulsed neutron sources.

  7. Multi-Agent Methods for the Configuration of Random Nanocomputers

    NASA Technical Reports Server (NTRS)

    Lawson, John W.

    2004-01-01

    As computational devices continue to shrink, the cost of manufacturing such devices is expected to grow exponentially. One alternative to the costly, detailed design and assembly of conventional computers is to place the nano-electronic components randomly on a chip. The price for such a trivial assembly process is that the resulting chip would not be programmable by conventional means. In this work, we show that such random nanocomputers can be adaptively programmed using multi-agent methods. This is accomplished through the optimization of an associated high dimensional error function. By representing each of the independent variables as a reinforcement learning agent, we are able to achieve convergence must faster than with other methods, including simulated annealing. Standard combinational logic circuits such as adders and multipliers are implemented in a straightforward manner. In addition, we show that the intrinsic flexibility of these adaptive methods allows the random computers to be reconfigured easily, making them reusable. Recovery from faults is also demonstrated.

  8. Hardware-efficient low-power 2-bit ternary ALU design in CNTFET technology

    NASA Astrophysics Data System (ADS)

    Lata Murotiya, Sneh; Gupta, Anu

    2016-05-01

    This paper proposes a hardware-efficient low-power 2-bit ternary arithmetic logic unit (TALU) design in carbon nano tube field effect transistor technology. The proposed TALU architecture combines adder-subtractor and Ex-OR cell in one cell, thereby reducing the number of transistors by 71% in comparison with other TALU architecture. Further, the proposed TALU is optimised at transistor level with a new pass-transistor logic-based encoder circuit. Hspice simulation results show that the proposed design attains great advantages in power and power-delay product for addition and multiplication operations than reported designs. For instant, at power supply of 0.9 V, the proposed TALU consumes on average 91% and 95% less energy compared to their existing counterparts, for addition and multiplication operations, respectively.

  9. Note: All-digital pulse-shrinking time-to-digital converter with improved dynamic range

    NASA Astrophysics Data System (ADS)

    Chen, Chun-Chi; Hwang, Chorng-Sii; Lin, Yi; Chen, Guan-Hong

    2016-04-01

    This paper proposes an all-digital pulse-shrinking time-to-digital converter (TDC) using the offset error cancellation circuitry to widen its dynamic range and to improve its accuracy. Although the TDC based on a pulse-shrinking mechanism can achieve a sub-gate resolution without circuit complexity, it possesses an undesired offset error that results in a nonzero lower bound appeared in its dynamic range and then affects its accuracy. The proposed cancellation circuitry for eliminating the offset error consists of a time adder with a delay line and a time subtractor with an identical delay line. The experimental TDC is implemented on Xilinx field programmable gate arrays and it also functions successfully in improving its dynamic range.

  10. Adiabatic quantum-flux-parametron cell library adopting minimalist design

    SciTech Connect

    Takeuchi, Naoki; Yamanashi, Yuki; Yoshikawa, Nobuyuki

    2015-05-07

    We herein build an adiabatic quantum-flux-parametron (AQFP) cell library adopting minimalist design and a symmetric layout. In the proposed minimalist design, every logic cell is designed by arraying four types of building block cells: buffer, NOT, constant, and branch cells. Therefore, minimalist design enables us to effectively build and customize an AQFP cell library. The symmetric layout reduces unwanted parasitic magnetic coupling and ensures a large mutual inductance in an output transformer, which enables very long wiring between logic cells. We design and fabricate several logic circuits using the minimal AQFP cell library so as to test logic cells in the library. Moreover, we experimentally investigate the maximum wiring length between logic cells. Finally, we present an experimental demonstration of an 8-bit carry look-ahead adder designed using the minimal AQFP cell library and demonstrate that the proposed cell library is sufficiently robust to realize large-scale digital circuits.

  11. System Radiographic Characterization of 7MV Self-Magnetic Pinch Diode on RITS-6

    NASA Astrophysics Data System (ADS)

    Webb, Tim J.; Johnston, Mark D.; Oliver, Bryan V.

    2011-10-01

    The 7 MV, 160 kA induction voltage adder RITS-6 is used as a test bed for research and development of sub-100 ns flash x-ray radiography of which the self-magnetic pinch (SMP) diode is an example. The x-ray source properties such as dose, source spatial distribution, and energy spectrum couple with the imaging detector sensitivity and blur to form the radiologic system performance which is also highly dependent on the imaging geometry. The system performance of some SMP diode configurations will be presented. Sandia is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.

  12. ASIC design of a digital fuzzy system on chip for medical diagnostic applications.

    PubMed

    Roy Chowdhury, Shubhajit; Roy, Aniruddha; Saha, Hiranmay

    2011-04-01

    The paper presents the ASIC design of a digital fuzzy logic circuit for medical diagnostic applications. The system on chip under consideration uses fuzzifier, memory and defuzzifier for fuzzifying the patient data, storing the membership function values and defuzzifying the membership function values to get the output decision. The proposed circuit uses triangular trapezoidal membership functions for fuzzification patients' data. For minimizing the transistor count, the proposed circuit uses 3T XOR gates and 8T adders for its design. The entire work has been carried out using TSMC 0.35 µm CMOS process. Post layout TSPICE simulation of the whole circuit indicates a delay of 31.27 ns and the average power dissipation of the system on chip is 123.49 mW which indicates a less delay and less power dissipation than the comparable embedded systems reported earlier.

  13. All-optical arithmetic unit with the help of terahertz-optical-asymmetric-demultiplexer-based tree architecture

    NASA Astrophysics Data System (ADS)

    Gayen, Dilip Kumar; Nath Roy, Jitendra

    2008-03-01

    An all-optical arithmetic unit with the help of terahertz-optical-asymmetric-demultiplexer (TOAD)-based tree architecture is proposed. We describe the all-optical arithmetic unit by using a set of all-optical multiplexer, all-optical full-adder, and optical switch. The all-optical arithmetic unit can be used to perform a fast central processor unit using optical hardware components. We have tried to exploit the advantages of both optical tree architecture and TOAD-based switch to design an integrated all-optical circuit that can perform binary addition, addition with carry, subtract with borrow, subtract (2's complement), double, increment, decrement, and transfer operations.

  14. Treatment of Solar Generation in Electric Utility Resource Planning (Presentation)

    SciTech Connect

    Cory, K.; Sterling, J.; Taylor, M.; McLaren, J.

    2014-01-01

    Today's utility planners have a different market and economic context than their predecessors, including planning for the growth of renewable energy. Through interviews and a questionnaire, the authors gathered information on utility supply planning and how solar is represented. Utilities were asked to provide their resource planning process details, key assumptions (e.g. whether DG is represented as supply or negative load), modeling methodology (e.g. type of risk analytics and candidate portfolio development), capacity expansion and production simulation model software, and solar project representation (project size, capacity value and integration cost adder). This presentation aims to begin the exchange of information between utilities, regulators and other stakeholders by capturing utility-provided information about: 1) how various utilities approach long-range resource planning; 2) methods and tools utilities use to conduct resource planning; and, 3) how solar technologies are considered in the resource planning process.

  15. Retrofit costs for lime/limestone FGD and lime spray drying at coal-fired utility boilers

    SciTech Connect

    Emmel, T.E.; Jones, J.W.

    1990-01-01

    The paper gives results of a research program the objective of which was to significantly improve engineering cost estimates currently being used to evaluate the economic effects of applying SO2 controls to existing coal-fired utility boilers. The costs of retrofitting conventional lime/limestone wet flue gas desulfurization (L/LS FGD) and lime spray drying (LSD) FGD at 100-200 coal-fired power plants are being estimated under this program. The retrofit capital cost estimating procedures used for L/LS FGD and LSD FGD make two cost adjustments to current procedures used to estimate FGD costs: cost adders (for items not normally included in FGD system costs; e.g., demolition and relocation of existing facilities) and cost multipliers (to adjust capital costs for site access, congestion, and underground obstructions).

  16. Large-area formation of self-aligned crystalline domains of organic semiconductors on transistor channels using CONNECT.

    PubMed

    Park, Steve; Giri, Gaurav; Shaw, Leo; Pitner, Gregory; Ha, Jewook; Koo, Ja Hoon; Gu, Xiaodan; Park, Joonsuk; Lee, Tae Hoon; Nam, Ji Hyun; Hong, Yongtaek; Bao, Zhenan

    2015-05-01

    The electronic properties of solution-processable small-molecule organic semiconductors (OSCs) have rapidly improved in recent years, rendering them highly promising for various low-cost large-area electronic applications. However, practical applications of organic electronics require patterned and precisely registered OSC films within the transistor channel region with uniform electrical properties over a large area, a task that remains a significant challenge. Here, we present a technique termed "controlled OSC nucleation and extension for circuits" (CONNECT), which uses differential surface energy and solution shearing to simultaneously generate patterned and precisely registered OSC thin films within the channel region and with aligned crystalline domains, resulting in low device-to-device variability. We have fabricated transistor density as high as 840 dpi, with a yield of 99%. We have successfully built various logic gates and a 2-bit half-adder circuit, demonstrating the practical applicability of our technique for large-scale circuit fabrication.

  17. Preliminary results of Linear Induction Accelerator LIA-200

    NASA Astrophysics Data System (ADS)

    Sharma, Archana; Senthil, K.; Praveen Kumar, D. D.; Mitra, S.; Sharma, V.; Patel, A.; Sharma, D. K.; Rehim, R.; Kolge, T. S.; Saroj, P. C.; Acharya, S.; Amitava, Roy; Rakhee, M.; Nagesh, K. V.; Chakravarthy, D. P.

    2010-05-01

    Repetitive Pulsed Power Technology is being developed keeping in mind the potential applications of this technology in material modifications, disinfections of water, timber, and food pasteurization etc. BARC has indigenously developed a Linear Induction Accelerator (LIA-200) rated for 200 kV, 4 kA, 100 ns, 10 Hz. The satisfactory performance of all the sub-systems including solid state power modulator, amorphous core based pulsed transformers, magnetic switches, water capacitors, water pulse- forming line, induction adder and field-emission diode have been demonstrated. This paper presents some design details and operational results of this pulsed power system. It also highlights the need for further research and development to build reliable and economic high-average power systems for industrial applications.

  18. Recent advances in the development of high average power induction accelerators for industrial and environmental applications

    SciTech Connect

    Neau, F.L.

    1994-12-31

    Short-pulse accelerator technology developed during time period from the early 60`s through the late 80`s is now being extended to high average power systems capable of being used in industrial and environmental applications. Processes requiring high dose levels and/or high volume throughput may require systems with beam power levels from several hundreds of kilowatts to megawatts. Processes may include chemical waste mitigation, flue gas cleanup, food pasteurization, and new forms of materials preparation and treatment. This paper will address the present status of high average power systems now in operation that use combinations of semiconductor and saturable core magnetic switches with inductive voltage adders to achieve MeV beams of electrons or x-rays over areas of 10,000 cm{sup 2} or more. Similar high average power technology is also being used below 1 MeV to drive repetitive ion beam sources for treatment of material surfaces.

  19. An efficient FPGA architecture for integer ƞth root computation

    NASA Astrophysics Data System (ADS)

    Rangel-Valdez, Nelson; Barron-Zambrano, Jose Hugo; Torres-Huitzil, Cesar; Torres-Jimenez, Jose

    2015-10-01

    In embedded computing, it is common to find applications such as signal processing, image processing, computer graphics or data compression that might benefit from hardware implementation for the computation of integer roots of order ?. However, the scientific literature lacks architectural designs that implement such operations for different values of N, using a low amount of resources. This article presents a parameterisable field programmable gate array (FPGA) architecture for an efficient Nth root calculator that uses only adders/subtractors and ? location memory elements. The architecture was tested for different values of ?, using 64-bit number representation. The results show a consumption up to 10% of the logical resources of a Xilinx XC6SLX45-CSG324C device, depending on the value of N. The hardware implementation improved the performance of its corresponding software implementations in one order of magnitude. The architecture performance varies from several thousands to seven millions of root operations per second.

  20. Development of ferrite logic devices for an arithmetic processor

    NASA Technical Reports Server (NTRS)

    Heckler, C. H., Jr.

    1972-01-01

    A number of fundamentally ultra-reliable, all-magnetic logic circuits are developed using as a basis a single element ferrite structure wired as a logic delay element. By making minor additions or changes to the basic wiring pattern of the delay element other logic functions such as OR, AND, NEGATION, MAJORITY, EXCLUSIVE-OR, and FAN-OUT are developed. These logic functions are then used in the design of a full-adder, a set/reset flip-flop, and an edge detector. As a demonstration of the utility of all the developed devices, an 8-bit, all-magnetic, logic arithmetic unit capable of controlled addition, subtraction, and multiplication is designed. A new basic ferrite logic element and associated complementary logic scheme with the potential of improved performance is also described. Finally, an improved batch process for fabricating joint-free power drive and logic interconnect conductors for this basic class of all-magnetic logic is presented.

  1. Progress on EUV pellicle development

    NASA Astrophysics Data System (ADS)

    Zoldesi, Carmen; Bal, Kursat; Blum, Brian; Bock, Guus; Brouns, Derk; Dhalluin, Florian; Dziomkina, Nina; Espinoza, Juan Diego Arias; de Hoogh, Joost; Houweling, Silvester; Jansen, Maarten; Kamali, Mohammad; Kempa, Alain; Kox, Ronald; de Kruif, Robert; Lima, Jorge; Liu, Yang; Meijer, Henk; Meiling, Hans; van Mil, Ijen; Reijnen, Marco; Scaccabarozzi, Luigi; Smith, Daniel; Verbrugge, Beatrijs; de Winters, Laurens; Xiong, Xugang; Zimmerman, John

    2014-04-01

    As EUV approaches high volume manufacturing, reticle defectivity becomes an even more relevant topic for further investigation. Current baseline strategy for EUV defectivity management is to design, build and maintain a clean system without pellicle. In order to secure reticle front side particle adders to an acceptable level for high volume manufacturing, EUV pellicle is being actively investigated. Last year ASML reported on our initial EUV pellicle feasibility. In this paper, we will update on our progress since then. We will also provide an update to pellicle requirements published last year. Further, we present experimental results showing the viability and challenges of potential EUV pellicle materials, including, material properties, imaging capability, scalability and manufacturability.

  2. Development of venom toxin-specific antibodies by DNA immunisation: rationale and strategies to improve therapy of viper envenoming.

    PubMed

    Harrison, R A

    2004-04-16

    DNA vaccination induces potent cellular immune responses against infectious and parasitic intracellular pathogens. This paper illustrates that DNA immunisation protocols can be adapted to induce high titre antibody responses with potential to improve the treatment of systemic snake envenoming that kills 20000 people annually in Africa. Envenoming by the saw-scaled vipers and puff adders are responsible for the majority of these deaths. DNA sequences encoding haemorrhagic, pro- and anti-coagulant and other haemostasis-disruptive venom toxins from these vipers showed extensive cross-specific and cross-generic sequence and structural similarities. The predicted antigenic profiles of these toxin sequences are utilised to design DNA immunisation constructs to generate toxin-specific antibodies with potential to polyspecifically neutralise venoms from the most medically-important African vipers. PMID:15068847

  3. A HIGH CURRENT, HIGH VOLTAGE SOLID-STATE PULSE GENERATOR FOR THE NIF PLASMA ELECTRODE POCKELS CELL

    SciTech Connect

    Arnold, P A; Barbosa, F; Cook, E G; Hickman, B C; Akana, G L; Brooksby, C A

    2007-07-27

    A high current, high voltage, all solid-state pulse modulator has been developed for use in the Plasma Electrode Pockels Cell (PEPC) subsystem in the National Ignition Facility. The MOSFET-switched pulse generator, designed to be a more capable plug-in replacement for the thyratron-switched units currently deployed in NIF, offers unprecedented capabilities including burst-mode operation, pulse width agility and a steady-state pulse repetition frequency exceeding 1 Hz. Capable of delivering requisite fast risetime, 17 kV flattop pulses into a 6 {Omega} load, the pulser employs a modular architecture characteristic of the inductive adder technology, pioneered at LLNL for use in acceleration applications, which keeps primary voltages low (and well within the capabilities of existing FET technology), reduces fabrication costs and is amenable to rapid assembly and quick field repairs.

  4. Design and implementation of an efficient single layer five input majority voter gate in quantum-dot cellular automata.

    PubMed

    Bahar, Ali Newaz; Waheed, Sajjad

    2016-01-01

    The fundamental logical element of a quantum-dot cellular automata (QCA) circuit is majority voter gate (MV). The efficiency of a QCA circuit is depends on the efficiency of the MV. This paper presents an efficient single layer five-input majority voter gate (MV5). The structure of proposed MV5 is very simple and easy to implement in any logical circuit. This proposed MV5 reduce number of cells and use conventional QCA cells. However, using MV5 a multilayer 1-bit full-adder (FA) is designed. The functional accuracy of the proposed MV5 and FA are confirmed by QCADesigner a well-known QCA layout design and verification tools. Furthermore, the power dissipation of proposed circuits are estimated, which shows that those circuits dissipate extremely small amount of energy and suitable for reversible computing. The simulation outcomes demonstrate the superiority of the proposed circuit. PMID:27330902

  5. Conceptual design for a linear-transformer driver (LTD)-based refurbishment and upgrade of the Saturn accelerator pulse-power system.

    SciTech Connect

    Mazarakis, Michael Gerrassimos; Struve, Kenneth William

    2006-09-01

    The purpose of this work was to develop a conceptual design for the Saturn accelerator using the modular Liner-Transformer Driver (LTD) technology to identify risks and to focus development and research for this new technology. We present a reference design for a Saturn class driver based on a number of linear inductive voltage adders connected in parallel. This design is very similar to a design reported five years ago [1]. However, with the design reported here we use 1-MA, 100-kV LTD cavities as building blocks. These cavities have already been built and are currently in operation at the HCEI in Tomsk, Russia [2]. Therefore, this new design integrates already-proven individual components into a full system design.

  6. Multi-bit binary decoder based on Belousov-Zhabotinsky reaction.

    PubMed

    Sun, Ming-Zhu; Zhao, Xin

    2013-03-21

    It is known that Belousov-Zhabotinsky (BZ) reaction can be applied to chemical computation, e.g., image processing, computational geometry, logical computation, and so on. In the field of logical computation, some basic logic gates and basic combinational logic circuits, such as adder, counter, memory cell, have already been implemented in simulations or in chemical experiments. In this paper, we focus on another important combinational logic circuit, binary decoder. Integrating AND gate and NOT gate, we first design and implement a one-bit binary decoder through numerical simulation. Then we show that one-bit decoder can be extended to design two-bit, three-bit, or even higher bit binary decoders by a cascade method. The simulation results demonstrate the effectiveness of these devices. The chemical realization of decoders can guide the construction of more sophisticated functions based on BZ reaction; meanwhile, the cascade method can facilitate the design of other combinational logic circuits.

  7. VLSI processors for signal detection in SETI

    NASA Technical Reports Server (NTRS)

    Duluk, J. F.; Linscott, I. R.; Peterson, A. M.; Burr, J.; Ekroot, B.; Twicken, J.

    1989-01-01

    The objective of the Search for Extraterrestrial Intelligence (SETI) is to locate an artificially created signal coming from a distant star. This is done in two steps: (1) spectral analysis of an incoming radio frequency band, and (2) pattern detection for narrow-band signals. Both steps are computationally expensive and require the development of specially designed computer architectures. To reduce the size and cost of the SETI signal detection machine, two custom VLSI chips are under development. The first chip, the SETI DSP Engine, is used in the spectrum analyzer and is specially designed to compute Discrete Fourier Transforms (DFTs). It is a high-speed arithmetic processor that has two adders, one multiplier-accumulator, and three four-port memories. The second chip is a new type of Content-Addressable Memory. It is the heart of an associative processor that is used for pattern detection. Both chips incorporate many innovative circuits and architectural features.

  8. Immunodiagnosis of snake bite.

    PubMed

    Greenwood, B M; Warrell, D A; Davidson, N M; Ormerod, L D; Reid, H A

    1974-12-28

    Management of a patient with snake bite is influenced by the nature of the offending snake. Species diagnosis based on the patient's history and physical signs is often unreliable and the possibility of making a species diagnosis by immunological means has therefore been investigated. Wound aspirates, blister fluids, sera, and urine samples from patients with snake bite were examined for the presence of species-specific venoms using immunodiffusion. A positive species diagnosis was made in 40 out of 101 patients. Immunodiagnosis was especially successful in patients bitten by the puff adder, Bitis arietans, and the African spitting cobra, Naja nigricollis. A higher success rate could probably be achieved using more specific antisera and more sensitive assay techniques. PMID:4216390

  9. VLSI implementation of moment invariants for automated inspection

    NASA Astrophysics Data System (ADS)

    Armstrong, G. A.; Simpson, M. L.; Bouldin, D. W.

    This paper describes the design of a very large scale integration (VLSI) application specific integrated circuit (ASIC) for use in automated inspection. The inspection scheme uses Hu and Maitra's algorithms for moment invariants. A prototype design was generated that resolved the long delay time of the multiplier by custom designing adder cells based on the Manchester carry chain. The prototype ASIC is currently being fabricated in 2.0-micron CMOS technology and has been simulated at 20 MHz. The final ASICs will be used in parallel at the board level to achieve the 230 MOPs necessary to perform the moment invariant algorithms in real time on 512 by 512 pixel images with 256 grey scales.

  10. Note: A pulsed laser ion source for linear induction accelerators

    SciTech Connect

    Zhang, H.; Zhang, K.; Shen, Y.; Jiang, X.; Dong, P.; Liu, Y.; Wang, Y.; Chen, D.; Pan, H.; Wang, W.; Jiang, W.; Long, J.; Xia, L.; Shi, J.; Zhang, L.; Deng, J.

    2015-01-15

    We have developed a high-current laser ion source for induction accelerators. A copper target was irradiated by a frequency-quadrupled Nd:YAG laser (266 nm) with relatively low intensities of 10{sup 8} W/cm{sup 2}. The laser-produced plasma supplied a large number of Cu{sup +} ions (∼10{sup 12} ions/pulse) during several microseconds. Emission spectra of the plasma were observed and the calculated electron temperature was about 1 eV. An induction voltage adder extracted high-current ion beams over 0.5 A/cm{sup 2} from a plasma-prefilled gap. The normalized beam emittance measured by a pepper-pot method was smaller than 1 π mm mrad.

  11. A two-dimensional advanced systolic array and its arithmetic architecture and design

    SciTech Connect

    Jun, M.S.

    1989-01-01

    The rapid advances in the very large scale integrated (VLSI) technology has created a flurry of research in designing future computer architectures. Many methods have been developed for parallel processing of algorithms by directly mapping them onto parallel architectures. We present new methodologies for design of systolic arrays and asynchronous arrays that implement recursive algorithms efficiently. Using the new methods, we develop a systolic array with very simple local interconnection for matrix multiplication which achieves optimal performance without using any undesirable properties such as preloading input data or global broadcasting. We prove the correctness of the matrix multiplication algorithms on the systolic array with space-time parameters. The implementations of the algorithms can be easily proved and can be systolically expanded. We also develop a multi-purpose built-in logic for asynchronous self-test (BLAST) modules in processing elements. An asynchronous array for matrix multiplication which can speed up the total computation time significantly is also presented. To demonstrate the power of the proposed systolic array, the array will be applied to the shortest path problem by using the partitioned mapping approach which will be the key to extend the computational capacity of VLSI architectures with fixed size. The utilization of partitioning algorithms can overcome difficulties in the management of a large-size graph. To achieve the highest possible computation speed of the systolic array, we develop a prefix carry-lookahead adder/subtractor which achieves the maximal possible parallelism. The new carry-lookahead design leads to a high-speed adders/subtractors with regular layout. The time complexity is 2log{sub 2}n - 1 while the Brent-Kung's scheme has 4log{sub 2}n.

  12. On the Circuit Complexity of Sigmoid Feedforward Neural Networks.

    PubMed

    Taylor, John G.; Beiu, Valeriu

    1996-10-01

    This paper aims to examine the circuit complexity of sigmoid activation feedforward artificial neural networks by placing them amongst several classic Boolean and threshold gate circuit complexity classes. The starting point is the class NN(k) defined by [Shawe-Taylor et al. (1992)] Classes of feedforward neural nets and their circuit complexity. Neural Networks 5(6), 971-977. For a better characterisation, we introduce two additional classes NN(k)(Delta) and NN(k)(Delta,epsilon) having less restrictive conditions than NN(k) concerning fan-in and accuracy, and proceed to prove relations amongst these three classes and well established circuit complexity classes. For doing that, a particular class of Boolean functions F(Delta) is first introduced and we show how a threshold gate circuit can be recursively built for any f(Delta) belonging to F(Delta). As the G-functions (computing the carries) are f(Delta) functions, a class of solutions is obtained for threshold gate adders. We then constructively prove the inclusions amongst circuit complexity classes. This is done by converting the sigmoid feedforward artificial neural network into an equivalent threshold gate circuit [Shawe-Taylor et al. (1992)]. Each threshold gate is then replaced by a multiple input adder having a binary tree structure, relaxing the logarithmic fan-in condition from ([Shawe-Taylor et al. 1992]) to (almost) polynomial. This means that larger classes of sigmoid activation feedforward neural networks can be implemented in polynomial size Boolean circuits with a small constant fan-in at the expense of a logarithmic factor increase in the number of layers. Similar results are obtained for threshold circuits, and are liked with the previous ones. The main conclusion is that there are interesting fan-in dependent depth-size tradeoffs when trying to digitally implement sigmoid activation feedforward neural networks. Copyright 1996 Elsevier Science Ltd

  13. Defect reduction for semiconductor memory applications using jet and flash imprint lithography

    NASA Astrophysics Data System (ADS)

    Ye, Zhengmao; Luo, Kang; Irving, J. W.; Lu, Xiaoming; Zhang, Wei; Fletcher, Brian; Liu, Weijun; Xu, Frank; LaBrake, Dwayne; Resnick, Douglas; Sreenivasan, S. V.

    2013-03-01

    Imprint lithography has been shown to be an effective technique for replication of nano-scale features. Jet and Flash Imprint Lithography (J-FIL) involves the field-by-field deposition and exposure of a low viscosity resist deposited by jetting technology onto the substrate. The patterned mask is lowered into the fluid which then quickly flows into the relief patterns in the mask by capillary action. Following this filling step, the resist is crosslinked under UV radiation, and then the mask is removed leaving a patterned resist on the substrate. Acceptance of imprint lithography for manufacturing will require demonstration that it can attain defect levels commensurate with the defect specifications of high end memory devices. Typical defectivity targets are on the order of 0.10/cm2. In previous studies, we have focused on defects such as random non-fill defects occurring during the resist filling process and repeater defects caused by interactions with particles on the substrate. In this work, we attempted to identify the critical imprint defect types using a mask with NAND Flash-like patterns at dimensions as small as 26nm. The two key defect types identified were line break defects induced by small particulates and airborne contaminants which result in local adhesion failure. After identification, the root cause of the defect was determined, and corrective measures were taken to either eliminate or reduce the defect source. As a result, we have been able to reduce defectivity levels by more than three orders of magnitude in only 12 months and are now achieving defectivity adders as small as 2 adders per lot of wafers.

  14. Square pulse linear transformer driver

    NASA Astrophysics Data System (ADS)

    Kim, A. A.; Mazarakis, M. G.; Sinebryukhov, V. A.; Volkov, S. N.; Kondratiev, S. S.; Alexeenko, V. M.; Bayol, F.; Demol, G.; Stygar, W. A.

    2012-04-01

    The linear transformer driver (LTD) technological approach can result in relatively compact devices that can deliver fast, high current, and high-voltage pulses straight out of the LTD cavity without any complicated pulse forming and pulse compression network. Through multistage inductively insulated voltage adders, the output pulse, increased in voltage amplitude, can be applied directly to the load. The usual LTD architecture [A. A. Kim, M. G. Mazarakis, V. A. Sinebryukhov, B. M. Kovalchuk, V. A. Vizir, S. N Volkov, F. Bayol, A. N. Bastrikov, V. G. Durakov, S. V. Frolov, V. M. Alexeenko, D. H. McDaniel, W. E. Fowler, K. LeCheen, C. Olson, W. A. Stygar, K. W. Struve, J. Porter, and R. M. Gilgenbach, Phys. Rev. ST Accel. Beams 12, 050402 (2009)PRABFM1098-440210.1103/PhysRevSTAB.12.050402; M. G. Mazarakis, W. E. Fowler, A. A. Kim, V. A. Sinebryukhov, S. T. Rogowski, R. A. Sharpe, D. H. McDaniel, C. L. Olson, J. L. Porter, K. W. Struve, W. A. Stygar, and J. R. Woodworth, Phys. Rev. ST Accel. Beams 12, 050401 (2009)PRABFM1098-440210.1103/PhysRevSTAB.12.050401] provides sine shaped output pulses that may not be well suited for some applications like z-pinch drivers, flash radiography, high power microwaves, etc. A more suitable power pulse would have a flat or trapezoidal (rising or falling) top. In this paper, we present the design and first test results of an LTD cavity that generates such a type of output pulse by including within its circular array a number of third harmonic bricks in addition to the main bricks. A voltage adder made out of a square pulse cavity linear array will produce the same shape output pulses provided that the timing of each cavity is synchronized with the propagation of the electromagnetic pulse.

  15. Design of a 5-MA 100-ns linear-transformer-driver accelerator for wire array Z-pinch experiments

    NASA Astrophysics Data System (ADS)

    Zhou, Lin; Li, Zhenghong; Wang, Zhen; Liang, Chuan; Li, Mingjia; Qi, Jianmin; Chu, Yanyun

    2016-03-01

    The linear-transformer-driver (LTD) is a recently developed pulsed-power technology that shows great promise for a number of applications. These include a Z -pinch-driven fission-fusion-hybrid reactor that is being developed by the Chinese Academy of Engineering Physics. In support of the reactor development effort, we are planning to build an LTD-based accelerator that is optimized for driving wire-array Z -pinch loads. The accelerator comprises six modules in parallel, each of which has eight series 0.8-MA LTD cavities in a voltage-adder configuration. Vacuum transmission lines are used from the interior of the adder to the central vacuum chamber where the load is placed. Thus the traditional stack-flashover problem is eliminated. The machine is 3.2 m tall and 12 m in outer diameter including supports. A prototype cavity was built and tested for more than 6000 shots intermittently at a repetition rate of 0.1 Hz. A novel trigger, in which only one input trigger pulse is needed by utilizing an internal trigger brick, was developed and successfully verified in these shots. A full circuit modeling was conducted for the accelerator. The simulation result shows that a current pulse rising to 5.2 MA in 91 ns (10%-90%) can be delivered to the wire-array load, which is 1.5 cm in height, 1.2 cm in initial radius, and 1 mg in mass. The maximum implosion velocity of the load is 32 cm /μ s when compressed to 0.1 of the initial radius. The maximum kinetic energy is 78 kJ, which is 11.7% of the electric energy stored in the capacitors. This accelerator is supposed to enable a radiation energy efficiency of 20%-30%, providing a high efficient facility for research on the fast Z pinch and technologies for repetition-rate-operated accelerators.

  16. Issues and methods in incorporating environmental externalities into the integrated resource planning process

    SciTech Connect

    Fang, J.M.; Galen, P.S.

    1994-11-01

    This report is a review of current practices and policies in considering environmental externalities in the integrated resource planning and performance based regulation (IRP/PBR) process. The following issues are presented and examined: What are the pros and cons of treating environmental externalities in the IRP process? How are potential future environmental regulations being treated? Are externalities being qualitatively or quantitatively considered, or monetized? Are offsets being allowed? How are externality policies being coordinated among different levels and branches of governments? Should environmental externalities be considered in dispatching a utility`s existing resources? What are the procedures for addressing uncertainty in incorporating environmental externalities into IRP? How are externalities valued? What are other approaches to addressing environmental externalities. This report describes seven major approaches for addressing environmental externalities in the IRP process: qualitative treatment, weighting and ranking, cost of control, damage function, percentage adders, monetization by emission, and multiattribute trade-off analysis. The discussion includes a taxonomy of the full range of alternative methods for addressing environmental externalities, a summary of state PUC actions, the role of state laws, the debate on environmental adders, and the choice of methodologies. In addition, this report characterizes the interests of stakeholders such as the electric industry, fuel suppliers, energy consumers, governmental agencies, public interest groups, consultants, and others. It appears that the views, positions, and interests of these stakeholders are affected by their perceptions of the potential impacts on their economic interests or the viability of their position on environmental policy, by the societal perspective they take, and by the orientation of the analysts toward market competition and their respective accumulated expertise.

  17. Climate-change-related shifts in annual phenology of a temperate snake during the last 20 years

    NASA Astrophysics Data System (ADS)

    Rugiero, Lorenzo; Milana, Giuliano; Petrozzi, Fabio; Capula, Massimo; Luiselli, Luca

    2013-08-01

    Global warming is thought to be a far-reaching threat to biodiversity, and is supposed to influence several aspects of the ecology of animals. Global warming should influence especially the ectotherm vertebrates, which depend directly from the external thermal conditions for their activities and performances. Here, we analyze the changes in phenology which have occurred in the last 20 years in a marked population of vipers, Vipera aspis, and we try to relate these changes with the intervening climatic changes. We analyzed three metrics of viper's annual phenology: (i) annual onset of above-ground activity (hereby AOA); (ii) annual onset of feeding period (AOF); (iii) annual onset of the hibernation (AOH). The annual variations of these three phenological metrics were correlated to five variables of climatic data: (1) mean annual air temperature, (2) mean February air temperature, (3) mean July air temperature, (4) yearly number of rainy days, and (5) yearly number of days with rainstorm. We observed a statistically significant reduction of AOA values from >28 days between 1987 and 1997, to approximately 20 days from 1998 to 2011, with a similar statistical trend also found for AOF values. The number of days of delay in entering hibernation increased significantly since 1998. Three sets of relationships between climatic variables and metrics of viper phenology were statistically significant, i.e. the correlation (i) between annual mean temperature and AOA (negative), (ii) between annual mean temperature and AOF (negative), and (iii) between annual mean temperature and AOH (positive). The percent of field days (between 20th February and 20th March) with no viper observed also decreased significantly over the years. Our study showed that three different traits of the annual phenology of a Mediterranean snake are shifting in the 20+ years of monitoring, and that there is correlational evidence that these shifts are linked to intervening climate change.

  18. Effect of ambient temperature in neonate aspic vipers: growth, locomotor performance and defensive behaviors.

    PubMed

    Aïdam, Aurélie; Michel, Catherine Louise; Bonnet, Xavier

    2013-07-01

    The impact of temperature during incubation and gestation has been tested in various reptiles; the postnatal period has been rarely investigated however. Three groups of newborn aspic vipers (Vipera aspis) were placed under contrasted thermal regimes during 7 months: (1) a cool 23°C constant regime, (2) a warm 28°C constant regime, and (3) an optimal regime with free-access to a wide range of temperatures. Later, all the snakes were placed under hibernation conditions (6°C) during 3 months. Finally all the snakes were placed in the optimal thermal regime during 2 additional months. The total duration of the experiment was of 12 months. Body mass and feeding rates were recorded weekly, body size was measured monthly. We also assessed locomotor performance and recorded several behavioral traits (e.g., defensive and predatory behaviors). As expected, snakes raised under cool temperatures exhibited low feeding rate, growth rate, body condition, and they exhibited poor locomotor performance; they also displayed marked defensive behaviors (e.g., high number of defensive bites) whilst hesitating during longer periods to bite a prey. Such behavioral effects were detected at the end of the experiment (i.e., 5 months after exposure to contrasted thermal treatments [3 months of hibernation plus 2 months of optimal regime]), revealing long term effects. Surprisingly, growth rate and locomotor performance were not different between the two other groups, warm constant 28°C versus optimal regimes (albeit several behavioral traits differed), suggesting that the access to a wide range of ambient temperatures was not a crucial factor.

  19. Last Neanderthals and first Anatomically Modern Humans in the NW Iberian Peninsula: Climatic and environmental conditions inferred from the Cova Eirós small-vertebrate assemblage during MIS 3

    NASA Astrophysics Data System (ADS)

    Rey-Rodríguez, Iván; López-García, Juan-Manuel; Bennàsar, Maria; Bañuls-Cardona, Sandra; Blain, Hugues-Alexandre; Blanco-Lapaz, Ángel; Rodríguez-Álvarez, Xosé-Pedro; de Lombera-Hermida, Arturo; Díaz-Rodríguez, Mikel; Ameijenda-Iglesias, Alicia; Agustí, Jordi; Fábregas-Valcarce, Ramón

    2016-11-01

    Cova Eirós is emerging as a reference site in the northwestern Iberian Peninsula for the study of the development of the last Neanderthal populations and the first populations of Anatomically Modern Humans (AMH) in MIS 3. Cova Eirós is an archaeological site (with Middle and Upper Palaeolithic levels) located in Cancelo, Triacastela (Lugo, northwestern Iberian Peninsula), which has been systematically excavated from 2008 onwards. The small-vertebrate assemblage analysed came from the archaeo-palaeontological field seasons that took place from 2009 to 2014. At least 18 small-vertebrate taxa have been identified: 1 frog (Rana temporaria), 1 snake (Vipera sp.), 4 insectivores (Sorex minutus, Sorex sp., Talpa cf. occidentalis and Erinaceus europaeus), 4 chiropters (Myotis myotis/blythii, cf. Miniopterus sp., Myotis sp. and Rhinolophus ferrumequinum) and 8 rodents (Apodemus sylvaticus, Arvicola amphibius, Arvicola sapidus, Chionomys nivalis, Microtus (Terricola) lusitanicus, Microtus agrestis, Microtus arvalis and Microtus oeconomus). Using the Habitat Weighting method to reconstruct the palaeoenvironment, we reconstruct a landscape for MIS 3 characterized by open woodland formations. The Mutual Ecogeographic Range (MER) method and the Bioclimatic Model (BM) used for the palaeoclimatic reconstruction show lower temperatures and higher precipitation than at present in the region. Our results from Cova Eirós are compared with the data obtained from several other sites in the Iberian Peninsula; it can be said that Neanderthals and AMH were well adapted to the territory that they occupied, as well as to the surrounding environment and the climatic conditions prevalent in the unstable context of MIS 3 in the Iberian Peninsula.

  20. Hemostatic interference of Indian king cobra (Ophiophagus hannah) Venom. Comparison with three other snake venoms of the subcontinent.

    PubMed

    Gowtham, Yashonandana J; Kumar, M S; Girish, K S; Kemparaju, K

    2012-06-01

    Unlike Naja naja, Bungarus caeruleus, Echis carinatus, and Daboia/Vipera russellii venoms, Ophiophagus hannah venom is medically ignored in the Indian subcontinent. Being the biggest poisonous snake, O. hannah has been presumed to inject several lethal doses of venom in a single bite. Lack of therapeutic antivenom to O. hannah bite in India makes any attempt to save the victim a difficult exercise. This study was initiated to compare O. hannah venom with the above said venoms for possible interference in hemostasis. Ophiophagus hannah venom was found to actively interfere in hemostatic stages such as fibrin clot formation, platelet activation/aggregation, and fibrin clot dissolution. It decreased partial thromboplastin time (aPTT), prothrombin time (PT), and thrombin clotting time (TCT). These activities are similar to that shown by E. carinatus and D. russellii venoms, and thus O. hannah venom was found to exert procoagulant activity through the common pathway of blood coagulation, while N. naja venom increased aPTT and TCT but not PT, and hence it was found to exert anticoagulant activity through the intrinsic pathway. Venoms of O. hannah, E. carinatus, and D. russellii lack plasminogen activation property as they do not hydrolyze azocasein, while they all show plasmin-like activity by degrading the fibrin clot. Although N. naja venom did not degrade azocasein, unlike other venoms, it showed feeble plasmin-like activity on fibrin clot. Venom of E. carinatus induced clotting of human platelet rich plasma (PRP), while the other three venoms interfered in agonist-induced platelet aggregation in PRP. Venom of O. hannah least inhibited the ADP induced platelet aggregation as compared to D. russellii and N. naja venoms. All these three venoms showed complete inhibition of epinephrine-induced aggregation at varied doses. However, O. hannah venom was unique in inhibiting thrombin induced aggregation. PMID:22817464

  1. Hemostatic interference of Indian king cobra (Ophiophagus hannah) Venom. Comparison with three other snake venoms of the subcontinent.

    PubMed

    Gowtham, Yashonandana J; Kumar, M S; Girish, K S; Kemparaju, K

    2012-06-01

    Unlike Naja naja, Bungarus caeruleus, Echis carinatus, and Daboia/Vipera russellii venoms, Ophiophagus hannah venom is medically ignored in the Indian subcontinent. Being the biggest poisonous snake, O. hannah has been presumed to inject several lethal doses of venom in a single bite. Lack of therapeutic antivenom to O. hannah bite in India makes any attempt to save the victim a difficult exercise. This study was initiated to compare O. hannah venom with the above said venoms for possible interference in hemostasis. Ophiophagus hannah venom was found to actively interfere in hemostatic stages such as fibrin clot formation, platelet activation/aggregation, and fibrin clot dissolution. It decreased partial thromboplastin time (aPTT), prothrombin time (PT), and thrombin clotting time (TCT). These activities are similar to that shown by E. carinatus and D. russellii venoms, and thus O. hannah venom was found to exert procoagulant activity through the common pathway of blood coagulation, while N. naja venom increased aPTT and TCT but not PT, and hence it was found to exert anticoagulant activity through the intrinsic pathway. Venoms of O. hannah, E. carinatus, and D. russellii lack plasminogen activation property as they do not hydrolyze azocasein, while they all show plasmin-like activity by degrading the fibrin clot. Although N. naja venom did not degrade azocasein, unlike other venoms, it showed feeble plasmin-like activity on fibrin clot. Venom of E. carinatus induced clotting of human platelet rich plasma (PRP), while the other three venoms interfered in agonist-induced platelet aggregation in PRP. Venom of O. hannah least inhibited the ADP induced platelet aggregation as compared to D. russellii and N. naja venoms. All these three venoms showed complete inhibition of epinephrine-induced aggregation at varied doses. However, O. hannah venom was unique in inhibiting thrombin induced aggregation.

  2. Biochemical and biological properties of phospholipases A(2) from Bothrops atrox snake venom.

    PubMed

    Kanashiro, Milton M; de Cássia M Escocard, Rita; Petretski, Jorge H; Prates, Maura V; Alves, Elias W; Machado, Olga L T; da Silva, Wilmar Dias; Kipnis, Thereza L

    2002-10-01

    Phospholipases A(2) (PLA(2)s), of molecular mass 13-15kDa, are commonly isolated from snake venom. Two myotoxins with PLA(2) activity, BaPLA(2)I and BaPLA(2)III, with estimated molecular masses of 15kDa were isolated from the venom of Bothrops atrox using Sephacryl S-100-HR and reverse-phase chromatography. BaPLA(2)I was basic, with a pI of 9.1, while BaPLA(2)III was neutral with a pI of 6.9. On a molecular basis, BaPLA(2)III exhibited higher catalytic activity on synthetic substrates than BaPLA(2)I. Comparison of the N-terminal residues of BaPLA(2)I with other PLA(2) proteins from snake venoms showed that it has the highest homology (94%) with B. asper myotoxin II and homology with a PLA(2) Lys(49) from B. atrox (89%). In contrast, BaPLA(2)III demonstrated 75, 72, and 71% homology with PLA(2) from Vipera ammodytes meridionalis, B. jararacussu, and B. jararaca, respectively. BaPLA(2)I and BaPLA(2)III were capable, in vitro, of inducing mast cell degranulation and, in vivo, of causing creatine kinase release, edema, and myonecrosis typical of PLA(2)s from snake venoms, characterized by rapid disruption of the plasma membrane as indicated by clumping of myofilaments and necrosis of affected skeletal muscle cells. BaPLA(2)I- and BaPLA(2)III-specific monoclonal and polyclonal antibodies, although incapable of neutralizing PLA(2) edematogenic activity, blocked myonecrosis efficiently in an in vivo neutralization assay. The results presented herein suggest that the biological active site responsible for edema induction by these two PLA(2) enzymes is distinct from the myonecrosis active site and is not dependent upon the catalytic activity of the PLA(2) enzyme. PMID:12234622

  3. Study of Sperm Reproductive Parameters in Mature Zanjani Viper

    PubMed Central

    Moshiri, Malihe; Todehdehghan, Fatemeh; Shiravi, Abdolhossein

    2014-01-01

    Objective Zanjani viper (Vipera albicornuta) is an endemic venomous snake in East Azerbai- jan Province, Iran which is medically important due to its application for antivenin production in the laboratory. We need to produce this snake in captivity. This study was conducted to charac- terize mature male Zanjani viper and to evaluate its sperm reproductive parameters. Materials and Methods This applied- descriptive study was conducted on twenty Zan- jani viper samples collected from Ag Dag Mountain in East Azarbaijan Province, Iran, between September and October 2010. After the snakes were anesthetized and sacrificed humanly, their morphometric specifications and sperm reproductive parameters, including concentration, motility, vitality, morphology, and survival time, were measured. Results Morphometric specifications and evaluation of sperms of the snake showed the following information: Zanjani male viper, body length of 73.65 ± 4.35 cm, tail length of 5.465 ± 0.48 cm, and mature snakes with testicular volumes of 0.61 ± 0.81 ml (right) and of 0.46 ± 0.17 ml (left). Our findings revealed average sperm concen- tration of 0.47 ± 0.1 ×106ml-1, motility of 49 -55 %, vitality of 46.11 ± 9.63 %, normal morphology of 61.71 ± 5.3%, and survival time of 6 ± 2 hours at the laboratory tem- perature. Statistical analyses were performed using Student’s t test for comparison of two values, and one-way ANOVA was applied where three values were compared. Conclusion Results suggest that mature Zanjani male viper with mature sperms in its vas deferens is present in late summer and early autumn seasons in Bostanabad County, Iran. PMID:24567940

  4. Spectroscopic investigation of calcium binding sites in the neurotoxin Vipoxin and its components-relation with the X-ray structure

    NASA Astrophysics Data System (ADS)

    Georgieva, Dessislava N.; Betzel, Christian; Aleksiev, Boris; Genov, Nicolay

    2000-12-01

    Vipoxin is a neurotoxin from the venom of Vipera ammodytes meridionalis, the most toxic snake in Europe. It is a unique complex of a toxic phospholipase A 2 (PLA 2) and a non-toxic PLA 2-like protein inhibitor (Inh) which probably evolved from the enzyme and reduces its activity and toxicity. The enzymatic activity of Vipoxin is Ca 2+-dependent and the interaction of this metal ion with the neurotoxic complex and its separated components was investigated using the fluorescent probe ANS. Vipoxin binds two calcium ions, one per each subunit. The X-ray model of the Ca 2+-free neurotoxin shows that the potential metal-binding sites require minor structural changes to bind calcium. The dissociation constants K Ca2+ of the calcium complexes of Vipoxin and its components, PLA 2 and Inh, were determined to be 16, 10 and 9 mM, respectively. The affinity for calcium of Vipoxin is reduced in comparison to those of PLA 2 and Inh. The X-ray model shows that the potential Ca 2+-binding sites in the two components are partially 'shielded' in the complex. The affinity of the neurotoxin to Sr 2+ and Ba 2+ is lower and the respective K Ca2+ are 20 and 30 mM. The saturation of Ca 2+-binding sites increased the melting point Tm of Vipoxin by 11°C and the activation energy for the thermal deactivation of the excited tryptophans Ea by 11 kJ mol -1. Ca 2+ is important not only for the enzymatic activity of Vipoxin but also for its thermostability.

  5. Estimating how inflated or obscured effects of climate affect forecasted species distribution.

    PubMed

    Real, Raimundo; Romero, David; Olivero, Jesús; Estrada, Alba; Márquez, Ana L

    2013-01-01

    Climate is one of the main drivers of species distribution. However, as different environmental factors tend to co-vary, the effect of climate cannot be taken at face value, as it may be either inflated or obscured by other correlated factors. We used the favourability models of four species (Alytes dickhilleni, Vipera latasti, Aquila fasciata and Capra pyrenaica) inhabiting Spanish mountains as case studies to evaluate the relative contribution of climate in their forecasted favourability by using variation partitioning and weighting the effect of climate in relation to non-climatic factors. By calculating the pure effect of the climatic factor, the pure effects of non-climatic factors, the shared climatic effect and the proportion of the pure effect of the climatic factor in relation to its apparent effect (ρ), we assessed the apparent effect and the pure independent effect of climate. We then projected both types of effects when modelling the future favourability for each species and combination of AOGCM-SRES (two Atmosphere-Ocean General Circulation Models: CGCM2 and ECHAM4, and two Special Reports on Emission Scenarios (SRES): A2 and B2). The results show that the apparent effect of climate can be either inflated (overrated) or obscured (underrated) by other correlated factors. These differences were species-specific; the sum of favourable areas forecasted according to the pure climatic effect differed from that forecasted according to the apparent climatic effect by about 61% on average for one of the species analyzed, and by about 20% on average for each of the other species. The pure effect of future climate on species distributions can only be estimated by combining climate with other factors. Transferring the pure climatic effect and the apparent climatic effect to the future delimits the maximum and minimum favourable areas forecasted for each species in each climate change scenario.

  6. Interactions of the Neurotoxin Vipoxin in Solution Studied by Dynamic Light Scattering

    PubMed Central

    Georgieva, Dessislava Nikolova; Genov, Nicolay; Hristov, Krassimir; Dierks, Karsten; Betzel, Christian

    2004-01-01

    The neurotoxin vipoxin is the lethal component of the venom of Vipera ammodytes meridionalis. It is a heterodimer of a basic toxic His-48 phospholipase A2 (PLA2) and an acidic nontoxic Gln-48 PLA2. The shape of the neurotoxin and its separated components in solution as well as their interactions with calcium, the brain phospholipid phosphatidylcholine, and two inhibitors, elaidoylamide and vitamin E, were investigated by dynamic light scattering. Calcium binding is connected with a conformational change in vipoxin observed as a change of the hydrodynamic shape from oblate ellipsoid to a shape closer to a sphere. The Ca2+-bound form of vipoxin, which is catalytically active, is more compact and symmetric than the calcium-free heterodimer. Similar changes were observed as a result of the Ca2+-binding to the two separated subunits. In the presence of aggregated phosphatidylcholine, the neurotoxic complex dissociates to subunits. It is supposed that only the toxic component binds to the substrate, and the other subunit, which plays a chaperone function, remains in solution. The inhibition of vipoxin with the synthetic inhibitor elaidoylamide and the natural compound vitamin E changes the shape of the toxin from oblate to prolate ellipsoid. The inhibited toxin is more asymmetric in comparison to the native one. Similar, but not so pronounced, effects were observed after the inhibition of the monomeric and homodimeric forms of the toxic His-48 PLA2. Circular dichroism measurements in the presence of urea, methylurea, and ethylurea indicate a strong hydrophobic stabilization of the neurotoxin. Hydrophobic interactions stabilize not only the folded regions but also the regions of intersubunit contacts. PMID:14695289

  7. Crystallographic characterization of functional sites of crotoxin and ammodytoxin, potent β-neurotoxins from Viperidae venom.

    PubMed

    Faure, Grazyna; Saul, Frederick

    2012-09-15

    This review will focus on a description of the three-dimensional structures of two β-neurotoxins, the monomeric PLA(2) ammodytoxin from Vipera ammodytes ammodytes, and heterodimeric crotoxin from Crotalus durissus terrificus, and a detailed structural analysis of their multiple functional sites. We have recently determined at high resolution the crystal structures of two natural isoforms of ammodytoxin (AtxA and AtxC) (Saul et al., 2010) which exhibit different toxicity profiles and different anticoagulant properties. Comparative structural analysis of these two PLA(2) isoforms, which differ only by two amino acid residues, allowed us to detect local conformational changes and delineate the role of critical residues in the anticoagulant and neurotoxic functions of these PLA(2) (Saul et al., 2010). We have also determined, at 1.35Å resolution, the crystal structure of heterodimeric crotoxin (Faure et al., 2011). The three-dimensional structure of crotoxin revealed details of the binding interface between its acidic (CA) and basic (CB) subunits and allowed us to identify key residues involved in the stability and toxicity of this potent heterodimeric β-neurotoxin (Faure et al., 2011). The precise spatial orientation of the three covalently linked polypeptide chains in the mature CA subunit complexed with CB helps us to understand the role played by critical residues of the CA subunit in the increased toxicity of the crotoxin complex. Since the CA subunit is a natural inhibitor of the catalytic and anticoagulant activities of CB, identification of the CA-CB binding interface describes residues involved in this inhibition. We propose future research directions based on knowledge of the recently reported 3D structures of crotoxin and ammodytoxin.

  8. Optical Computing Using Interference Filters as Nonlinear Optical Logic Gates and Holographic Optical Elements as Optical Interconnects.

    NASA Astrophysics Data System (ADS)

    Wang, Lon A.

    This dissertation experimentally explores digital optical computing and optical interconnects with theoretical supports, from the physics of materials and the optimization of devices to system realization. The trend of optical computing is highlighted with the emphasis on the current development of its basic constituent elements, and a couple of algorithms selected to pave the way for utilizing bistable devices for their optical implementations. Optical bistable devices function as "optical transistors" in optical computing. The physics of dispersive optical bistability is briefly described. Bistable ZnS interference filters are discussed in detail regarding their linear and nonlienar characteristics. The optimization of switching characteristics for a bistable ZnS interference filter is discussed, and experimental results are shown. Symbolic substitution which fully takes advantage of regular optical interconnects constitutes two steps: pattern recognition and symbol scription. Two experiments on two digital pattern recognitions and one on a simple but complete symbolic substitution have been demonstrated. The extension of these experiments is an implementation of a binary adder. A one-bit full adder which is a basic block for a computer has been explored experimentally and demonstrated in an all-optical way. The utilization of a bistable device as a nonlinear decision-making element is further demonstrated in an associative memory experiment by incorporating a Vander Lugt matched filter to discriminate two partial fingerprints. The thresholding function of a bistable device enhances the S/N ratio and helps discrimination in associative memory. As the clocking speed of a computer goes higher, e.g. greater than several GHz, the clock signal distribution and packaging become serious problems in VLSI technology. The use of optical interconnects introduces a possible solution. A unique element for holographic optical interconnects, which combines advantages of

  9. Fast and Scalable Computation of the Forward and Inverse Discrete Periodic Radon Transform.

    PubMed

    Carranza, Cesar; Llamocca, Daniel; Pattichis, Marios

    2016-01-01

    The discrete periodic radon transform (DPRT) has extensively been used in applications that involve image reconstructions from projections. Beyond classic applications, the DPRT can also be used to compute fast convolutions that avoids the use of floating-point arithmetic associated with the use of the fast Fourier transform. Unfortunately, the use of the DPRT has been limited by the need to compute a large number of additions and the need for a large number of memory accesses. This paper introduces a fast and scalable approach for computing the forward and inverse DPRT that is based on the use of: a parallel array of fixed-point adder trees; circular shift registers to remove the need for accessing external memory components when selecting the input data for the adder trees; an image block-based approach to DPRT computation that can fit the proposed architecture to available resources; and fast transpositions that are computed in one or a few clock cycles that do not depend on the size of the input image. As a result, for an N × N image (N prime), the proposed approach can compute up to N(2) additions per clock cycle. Compared with the previous approaches, the scalable approach provides the fastest known implementations for different amounts of computational resources. For example, for a 251×251 image, for approximately 25% fewer flip-flops than required for a systolic implementation, we have that the scalable DPRT is computed 36 times faster. For the fastest case, we introduce optimized just 2N + ⌈log(2) N⌉ + 1 and 2N + 3 ⌈log(2) N⌉ + B + 2 cycles, architectures that can compute the DPRT and its inverse in respectively, where B is the number of bits used to represent each input pixel. On the other hand, the scalable DPRT approach requires more 1-b additions than for the systolic implementation and provides a tradeoff between speed and additional 1-b additions. All of the proposed DPRT architectures were implemented in VHSIC Hardware Description Language

  10. Inferring the absence of a species -- a case study of snakes

    USGS Publications Warehouse

    Kery, M.

    2002-01-01

    Though the presence of a species can be unequivocally confirmed, its absence can only be inferred with a degree of probability. I used a model to calculate the minimum number of unsuccessful visits to a site that are necessary to assume that a species is absent. The model requires the probability of detection of the species per visit to be known. This probability, may vary depending on habitat, year, season, the area surveyed, the population size of the species, and the observer. I studied 3 European snake species---asp viper (Vipera aspis), smooth snake (Coronella austriaca), and grass snake (Natrix natrix)--over a 5-yr (1994--1998) interval, and made 645 visits to 87 sites during their activity periods. I used a generalized logistic regression approach with random effects for years and sites to (1) estimate the probability of detection of these species from sites known to be occupied, (2) test factors affecting it, and (3) compute the minimum number of times that a site must be visited to infer the absence of the particular species. Probability of detection for all species was heavily influenced by an index of population size. For V. aspis, probability, of detection increased from 0.23 to 0.50 and 0.70 in small, medium, and large populations, respectively. Similarly, probability of detection increased from 0.09 to 0.45 and 0.56 in small, medium, and large populations of C. austriaca, respectively, and from 0.11 in small to 0.25 in medium and large populations of N. natrix. Probability of detection also varied across months for all 3 species, among habitat types ( C. austriaca only), and from year to year (N. natrix only). Sites with unknown occupancy status conservatively may be assumed to be occupied by small populations. I calculated that such sites need to be surveyed 12, 34, and 26 times for V. aspis, C. austriaca, and N. natrix, respectively, before assuming with 95% probability that the site is unoccupied. These results suggest that some species may be more

  11. Acute toxicity of vipoxin and its components: is the acidic component an "inhibitor" of PLA2 toxicity?

    PubMed

    Atanasov, Vasil N; Stoykova, Silviya; Goranova, Yana; Mitewa, Mariana; Petrova, Svetla

    2012-12-01

    Vipoxin is a heterodimeric neurotoxin isolated from the venom of the Bulgarian long-nosed viper Vipera ammodytes meridionalis. Vipoxin represents a noncovalent association of two subunits - a basic and toxic phospholipase A2 enzyme, and an acidic non-enzymatic component (vipoxin's acidic component). It was postulated that the phospholipase A2 subunit was more toxic than the whole vipoxin complex and the function of the acidic component was to reduce the enzymatic and toxic activities of the basic phospholipase A2. In the present study, we report new data on the acute toxicity (LD50) of vipoxin and its individual separated components. Vipoxin LD50 (mice, i.p. and i.v.) values were found to be 0.7-1.2 mg/kg b.w. (i.p.) and 0.9-1.3 mg/kg b.w. (i.v.). The established LD50 values for the separated pure phospholipase A2 subunit are higher - 10.0-13.0 mg/kg b.w (i.p.) and 2.2-3.0 mg/kg b.w. (i.v.), i.e. the individual phospholipase A2 subunit displays less toxic activity than vipoxin, contrary to the data published in the literature. The reconstituted vipoxin complex (obtained after preliminary incubation of pure separated phospholipase A2 and acidic component showed enzyme activity and toxicity comparable to that of the native vipoxin complex. Addition of acidic component to the phospholipase A2 subunit showed a positive effect on the enzymatic activity, reaching maximal enzyme reaction rate of acidic component to phospholipase A2 molar ratio of 0.8:1 on using 4-nitro-3-octanoyloxy-benzoic acid as substrate. For the first time we showed that the acidic subunit was absolutely required for the toxic activity of vipoxin. Based on the obtained results, we assume that the function of the acidic component is to stabilize the neurotoxin's quaternary structure, required for its toxic and enzymatic activities, similarly to the role of the acidic component of crotoxin. PMID:23554559

  12. Design of easily testable systems

    SciTech Connect

    Rawat, S.S.

    1988-01-01

    This thesis presents structured testability techniques that can be applied to systolic arrays. Systolic arrays for signal processing have produced processing rates far in excess of general-purpose architecture. Fast testing is considered as one of the design criteria. The main goal is to derive test vectors for one- and two-dimensional systolic arrays. The author seeks to keep the number of test vectors independent of the size of the array under a generic fault model. The testable design is based on pseudo-exhaustive testing. Conventional testing uses Level Sensitive Scan Detection (LSSD) techniques which are very time consuming for an array of systolic processors. By making the testability analysis early the logic designer will be able to make early (and repeated) design trade-offs that make design for testability a simple extension of the design process. The author shows how one-dimensional sequential systolic arrays can be designed so that the faults can be easily detected and isolated. He also considers unilateral two-dimensional sequential arrays and suggests modifications to make them easily testable. Finally, he shows how a modified carry look ahead adder of arbitrary size can be tested with just 136 test vectors. Comparisons are made against the standard LSSD technique.

  13. Techniques for design and testing of iterative and systolic arrays. [C-testability concept

    SciTech Connect

    Elhuni, H.A.

    1986-01-01

    In this thesis, the author studies the issue of testing array-type structures such as iterative arrays of combinational cells and systolic arrays with a constant number of test vectors independent of the array size (C-Testability). The main contribution of this work is the extension of the C-testability concept in different directions. It is extended to orthogonally connected iterative arrays in chapter three. This is a contribution to the C-testability theory because of the undecidability property of general two-dimensional arrays. The C-testability is extended further to hexagonal iterative arrays in chapter four. The application of the C-testability concept was limited to few arrays such as ripple-carry adders, bit-sliced microprocessors and array multipliers. In chapter five, the author extended the concept to systolic arrays and apply it to some systolic designs. The application to hexagonal systolic arrays is made in chapter six. It is shown that several systolic arrays such as those used for matrix multiplication can be tested with a small number of test vectors; twice the number required to test a single cell. The testing time of such arrays is also introduced and discussed. In chapter seven, he introduces a new concept called STV-testability for testing bilateral systolic arrays. STV-testable arrays have simple test generation and verification procedures.

  14. Qualification of local advanced cryogenic cleaning technology for 14nm photomask fabrication

    NASA Astrophysics Data System (ADS)

    Taumer, Ralf; Krome, Thorsten; Bowers, Chuck; Varghese, Ivin; Hopkins, Tyler; White, Roy; Brunner, Martin; Yi, Daniel

    2014-10-01

    The march toward tighter design rules, and thus smaller defects, implies stronger surface adhesion between defects and the photomask surface compared to past generations, thereby resulting in increased difficulty in photomask cleaning. Current state-of-the-art wet clean technologies utilize functional water and various energies in an attempt to produce similar yield to the acid cleans of previous generations, but without some of the negative side effects. Still, wet cleans have continued to be plagued with issues such as persistent particles and contaminations, SRAF and feature damages, leaving contaminants behind that accelerate photo-induced defect growth, and others. This paper details work done through a design of experiments (DOE) utilized to qualify an improved cryogenic cleaning technology for production in the Advanced Mask Technology Center (AMTC) advanced production lines for 20 and 14 nm processing. All work was conducted at the AMTC facility in Dresden, Germany utilizing technology developed by Eco-Snow Systems and RAVE LLC for their cryogenic local cleaning VC1200F platform. This system uses a newly designed nozzle, improved gaseous CO2 delivery, extensive filtration to remove hydrocarbons and minimize particle adders, and other process improvements to overcome the limitations of the previous generation local cleaning tool. AMTC has successfully qualified this cryogenic cleaning technology and is currently using it regularly to enhance production yields even at the most challenging technology nodes.

  15. Circuit and method for producing a flexible reference voltage

    NASA Technical Reports Server (NTRS)

    Thornton, Roger D. (Inventor)

    1993-01-01

    A flexible reference voltage circuit includes a circuit for producing a first digital signal representative of a range of reference voltage levels; a circuit for producing a second digital signal representative of a selected reference voltage level within the range of reference voltage levels; an adder for adding the first and second digital signals to produce a third digital signal; and a digital to analog converter for providing an output voltage in response to the third digital signal. The method of producing a flexible reference voltage performed by the circuit is also claimed. The invention can be used with a differential protection circuit to provide a series of trip level ranges, with a series of selectable trip levels in each range. This is accomplished in a high accuracy circuit which is relatively simple to construct, thereby minimizing size and complexity of the current sensor module, in differential protection applications, or the circuitry, if used in a power system controller. Standard digital logic components can be used to perform the necessary range/level decoding.

  16. Fast Parallel Molecular Algorithms for DNA-Based Computation: Solving the Elliptic Curve Discrete Logarithm Problem over GF(2n)

    PubMed Central

    Li, Kenli; Zou, Shuting; Xv, Jin

    2008-01-01

    Elliptic curve cryptographic algorithms convert input data to unrecognizable encryption and the unrecognizable data back again into its original decrypted form. The security of this form of encryption hinges on the enormous difficulty that is required to solve the elliptic curve discrete logarithm problem (ECDLP), especially over GF(2n), n ∈ Z+. This paper describes an effective method to find solutions to the ECDLP by means of a molecular computer. We propose that this research accomplishment would represent a breakthrough for applied biological computation and this paper demonstrates that in principle this is possible. Three DNA-based algorithms: a parallel adder, a parallel multiplier, and a parallel inverse over GF(2n) are described. The biological operation time of all of these algorithms is polynomial with respect to n. Considering this analysis, cryptography using a public key might be less secure. In this respect, a principal contribution of this paper is to provide enhanced evidence of the potential of molecular computing to tackle such ambitious computations. PMID:18431451

  17. Reliability automation tool (RAT) for fault tolerance computation

    NASA Astrophysics Data System (ADS)

    Singh, N. S. S.; Hamid, N. H.; Asirvadam, V. S.

    2012-09-01

    As CMOS transistors reduced in size, the circuit built using these nano-scale transistors naturally becomes less reliable. The reliability reduction, which is the measure of circuit performance, has brought up so many challenges in designing modern logic integrated circuit. Therefore, reliability modeling is increasingly important subject to be considered in designing modern logic integrated circuit. This drives a need to compute reliability measures for nano-scale circuits. This paper looks into the development of reliability automation tool (RAT) for circuit's reliability computation. The tool is developed using Matlab programming language based on the reliability evaluation model called Probabilistic Transfer Matrix (PTM). RAT allows users to significantly speed-up the reliability assessments of nano-scale circuits. Users have to provide circuit's netlist as the input to RAT for its reliability computation. The netlist signifies the circuit's description in terms of Gate Profile Matrix (GPM), Adjacency Computation Matrix (ACM) and Grid Layout Matrix (GLM). GPM, ACM and GLM indicate the types of logic gates, the interconnection between these logic gates and the layout matrix of these logic gates respectively in a given circuit design. Here, the reliability assessment by RAT is carried out on Full Adder circuit as the benchmark test circuit.

  18. Public health aspects of snakebite care in West Africa: perspectives from Nigeria

    PubMed Central

    2013-01-01

    Snakebite envenoming is a major public health problem among rural communities of the Nigerian savanna. The saw-scaled or carpet viper (Echis ocellatus) and, to a lesser extent, the African cobras (Naja spp.) and puff adders (Bitis arietans) have proved to be the most important cause of mortality and morbidity. The main clinical features of E. ocellatus envenoming are systemic hemorrhage, incoagulable blood, shock, local swelling, bleeding and, occasionally, necrosis. Bites may be complicated by amputation, blindness, disability, disfigurement, mutilation, tissue destruction and psychological consequences. Antivenom remains the hallmark and mainstay of envenoming management while studies in Nigeria confirm its protection of over 80% against mortality from carpet-viper bites. However, the availability, distribution and utilization of antivenom remain challenging although two new antivenoms (monospecific EchiTab G and trispecific EchiTab ICP-Plus) derived from Nigerian snake venoms have proven very effective and safe in clinical trials. A hub-and-spoke strategy is suggested for broadening antivenom access to endemic rural areas together with instituting quality assurance, standardization and manpower training. With the advent of antivenomics, national health authorities must be aided in selecting and purchasing antivenoms appropriate to their national needs while manufacturers should be helped in practical ways to improve the safety, efficacy and potential coverage against snake venoms and pricing of their products. PMID:24134780

  19. An accelerator facility for WDM, HEDP, and HIF investigations in Nazarbayev University

    NASA Astrophysics Data System (ADS)

    Kaikanov, M.; Baigarin, K.; Tikhonov, A.; Urazbayev, A.; Kwan, J. W.; Henestroza, E.; Remnev, G.; Shubin, B.; Stepanov, A.; Shamanin, V.; Waldron, W. L.

    2016-05-01

    Nazarbayev University (NU) in Astana, Kazakhstan, is planning to build a new multi-MV, ∼10 to several hundred GW/cm2 ion accelerator facility which will be used in studies of material properties at extreme conditions relevant to ion-beam-driven inertial fusion energy, and other applications. Two design options have been considered. The first option is a 1.2 MV induction linac similar to the NDCX-II at LBNL, but with modifications, capable of heating a 1 mm spot size thin targets to a few eV temperature. The second option is a 2 - 3 MV, ∼200 kA, single-gap-diode proton accelerator powered by an inductive voltage adder. The high current proton beam can be focused to ∼1 cm spot size to obtain power densities of several hundred GW/cm2, capable of heating thick targets to temperatures of tens of eV. In both cases, a common requirement to achieving high beam intensity on target and pulse length compression is to utilize beam neutralization at the final stage of beam focusing. Initial experiments on pulsed ion beam neutralization have been carried out on a 0.3 MV, 1.5 GW single-gap ion accelerator at Tomsk Polytechnic University with the goal of creating a plasma region in front of a target at densities exceeding ∼1012 cm-3.

  20. Development of high frequency spice models for ferrite core inductors and transformers

    SciTech Connect

    Muyshondt, G.P.; Portnoy, W.M. . Dept. of Electrical Engineering)

    1989-01-01

    In this work high frequency SPICE models were developed to simulate the hysteresis and saturation effects of toroidal shaped ferrite core inductors and transformers. The models include the nonlinear, multi-valued B-H characteristic of the core material, leakage flux, stray capacitances, and core losses. The saturation effects were modeled using two diode clamping arrangements in conjunction with nonlinear dependent sources. Two possible controlling schemes were developed for the saturation switch. One of the arrangements used the current flowing through a series RC branch to control the switch, while the other used a NAND gate. The NAND gate implementation of the switch proved to be simpler and the parameters associated with it were easier to determine from the measurements and the B-H characteristics of the material. Lumped parameters were used to simulate the parasitic effects. Techniques for measuring these parasitic are described. The models were verified using manganese-zinc ferrite-type toroidal cores and they have general applicability to all circuit analysis codes equivalent function blocks such as multipliers, adders, and logic components. 7 refs., 22 figs.

  1. A precision analogue integrator system for heavy current measurement in MFDC resistance spot welding

    NASA Astrophysics Data System (ADS)

    Xia, Yu-Jun; Zhang, Zhong-Dian; Xia, Zhen-Xin; Zhu, Shi-Liang; Zhang, Rui

    2016-02-01

    In order to control and monitor the quality of middle frequency direct current (MFDC) resistance spot welding (RSW), precision measurement of the welding current up to 100 kA is required, for which Rogowski coils are the only viable current transducers at present. Thus, a highly accurate analogue integrator is the key to restoring the converted signals collected from the Rogowski coils. Previous studies emphasised that the integration drift is a major factor that influences the performance of analogue integrators, but capacitive leakage error also has a significant impact on the result, especially in long-time pulse integration. In this article, new methods of measuring and compensating capacitive leakage error are proposed to fabricate a precision analogue integrator system for MFDC RSW. A voltage holding test is carried out to measure the integration error caused by capacitive leakage, and an original integrator with a feedback adder is designed to compensate capacitive leakage error in real time. The experimental results and statistical analysis show that the new analogue integrator system could constrain both drift and capacitive leakage error, of which the effect is robust to different voltage levels of output signals. The total integration error is limited within  ±0.09 mV s-1 0.005% s-1 or full scale at a 95% confidence level, which makes it possible to achieve the precision measurement of the welding current of MFDC RSW with Rogowski coils of 0.1% accuracy class.

  2. A learnable parallel processing architecture towards unity of memory and computing

    NASA Astrophysics Data System (ADS)

    Li, H.; Gao, B.; Chen, Z.; Zhao, Y.; Huang, P.; Ye, H.; Liu, L.; Liu, X.; Kang, J.

    2015-08-01

    Developing energy-efficient parallel information processing systems beyond von Neumann architecture is a long-standing goal of modern information technologies. The widely used von Neumann computer architecture separates memory and computing units, which leads to energy-hungry data movement when computers work. In order to meet the need of efficient information processing for the data-driven applications such as big data and Internet of Things, an energy-efficient processing architecture beyond von Neumann is critical for the information society. Here we show a non-von Neumann architecture built of resistive switching (RS) devices named “iMemComp”, where memory and logic are unified with single-type devices. Leveraging nonvolatile nature and structural parallelism of crossbar RS arrays, we have equipped “iMemComp” with capabilities of computing in parallel and learning user-defined logic functions for large-scale information processing tasks. Such architecture eliminates the energy-hungry data movement in von Neumann computers. Compared with contemporary silicon technology, adder circuits based on “iMemComp” can improve the speed by 76.8% and the power dissipation by 60.3%, together with a 700 times aggressive reduction in the circuit area.

  3. An Enhanced Dual-Path ΔΣ A/D Converter

    NASA Astrophysics Data System (ADS)

    Nishida, Yoshio; Hamashita, Koichi; Temes, Gabor C.

    This paper presents an enhanced dual-path delta-sigma analog-to-digital converter. Compared with other architectures, the enhanced architecture increases the noise shaping order without any instability problems and displays analog complexity equivalent to the multi-stage noise shaping architecture. Our delta-sigma converter is based on this new architecture. It employs not only doubly-differential structure to reduce common-mode errors in the system-level but also delayed-feed-in structure to mitigate the timing constraint of the feedback signal. Regarding the circuit implementation, the first-order enhancement of the quantization noise shaping is achieved via the use of a switched capacitor circuit technique. The circuit is incorporated into the active adder in a low-distortion structure. The supporting clock generation circuit that provides additional phases of clocks with the enhancement block is also implemented in the CMOS logic gates. A digital dynamic element matching circuit (i.e., segmented data-weighted-average circuit) is designed to reduce mismatch errors caused by the feedback DAC of modulator. A test chip, fabricated in a 0.18-µm CMOS process, provides a signal-to-noise+distortion ratio (SNDR) of 75-dB for a 1.0-MHz signal bandwidth clocked at 40-MHz. The 2nd harmonic is -101dB and the 3rd harmonic is -94dB when a -4.5-dB 100-kHz input signal is applied.

  4. Investigation of a novel common subexpression elimination method for low power and area efficient DCT architecture.

    PubMed

    Siddiqui, M F; Reza, A W; Kanesan, J; Ramiah, H

    2014-01-01

    A wide interest has been observed to find a low power and area efficient hardware design of discrete cosine transform (DCT) algorithm. This research work proposed a novel Common Subexpression Elimination (CSE) based pipelined architecture for DCT, aimed at reproducing the cost metrics of power and area while maintaining high speed and accuracy in DCT applications. The proposed design combines the techniques of Canonical Signed Digit (CSD) representation and CSE to implement the multiplier-less method for fixed constant multiplication of DCT coefficients. Furthermore, symmetry in the DCT coefficient matrix is used with CSE to further decrease the number of arithmetic operations. This architecture needs a single-port memory to feed the inputs instead of multiport memory, which leads to reduction of the hardware cost and area. From the analysis of experimental results and performance comparisons, it is observed that the proposed scheme uses minimum logic utilizing mere 340 slices and 22 adders. Moreover, this design meets the real time constraints of different video/image coders and peak-signal-to-noise-ratio (PSNR) requirements. Furthermore, the proposed technique has significant advantages over recent well-known methods along with accuracy in terms of power reduction, silicon area usage, and maximum operating frequency by 41%, 15%, and 15%, respectively.

  5. An improved YEF-DCT based compression algorithm for video capsule endoscopy.

    PubMed

    Mostafa, Atahar; Khan, Tareq; Wahid, Khan

    2014-01-01

    Video capsule endoscopy is a non-invasive technique to receive images of intestine for medical diagnostics. The main design challenges of endoscopy capsule are accruing and transmitting acceptable quality images by utilizing as less hardware and battery power as possible. In order to save wireless transmission power and bandwidth, an efficient image compression algorithm needs to be implemented inside the endoscopy electronic capsule. In this paper, an integer discrete-cosine-transform (DCT) based algorithm is presented that works on a low-complexity color-space specially designed for wireless capsule endoscopy application. First of all, thousands of human endoscopic images and video frames have been analyzed to identify special intestinal features present in those frames. Then a color space, referred as YEF, is used. The YEF converter is lossless and takes only a few adders and shift operation to implement. A low-cost quantization scheme with variable chroma sub-sampling options is also implemented to achieve higher compression. Comparing with the existing works, the proposed transform coding based compressor performs strongly with an average compression ratio of 85% and a high image quality index, peak-signal-to-noise ratio (PSNR) of 52 dB.

  6. Area and power efficient DCT architecture for image compression

    NASA Astrophysics Data System (ADS)

    Dhandapani, Vaithiyanathan; Ramachandran, Seshasayanan

    2014-12-01

    The discrete cosine transform (DCT) is one of the major components in image and video compression systems. The final output of these systems is interpreted by the human visual system (HVS), which is not perfect. The limited perception of human visualization allows the algorithm to be numerically approximate rather than exact. In this paper, we propose a new matrix for discrete cosine transform. The proposed 8 × 8 transformation matrix contains only zeros and ones which requires only adders, thus avoiding the need for multiplication and shift operations. The new class of transform requires only 12 additions, which highly reduces the computational complexity and achieves a performance in image compression that is comparable to that of the existing approximated DCT. Another important aspect of the proposed transform is that it provides an efficient area and power optimization while implementing in hardware. To ensure the versatility of the proposal and to further evaluate the performance and correctness of the structure in terms of speed, area, and power consumption, the model is implemented on Xilinx Virtex 7 field programmable gate array (FPGA) device and synthesized with Cadence® RTL Compiler® using UMC 90 nm standard cell library. The analysis obtained from the implementation indicates that the proposed structure is superior to the existing approximation techniques with a 30% reduction in power and 12% reduction in area.

  7. Investigation of a Novel Common Subexpression Elimination Method for Low Power and Area Efficient DCT Architecture

    PubMed Central

    Siddiqui, M. F.; Reza, A. W.; Kanesan, J.; Ramiah, H.

    2014-01-01

    A wide interest has been observed to find a low power and area efficient hardware design of discrete cosine transform (DCT) algorithm. This research work proposed a novel Common Subexpression Elimination (CSE) based pipelined architecture for DCT, aimed at reproducing the cost metrics of power and area while maintaining high speed and accuracy in DCT applications. The proposed design combines the techniques of Canonical Signed Digit (CSD) representation and CSE to implement the multiplier-less method for fixed constant multiplication of DCT coefficients. Furthermore, symmetry in the DCT coefficient matrix is used with CSE to further decrease the number of arithmetic operations. This architecture needs a single-port memory to feed the inputs instead of multiport memory, which leads to reduction of the hardware cost and area. From the analysis of experimental results and performance comparisons, it is observed that the proposed scheme uses minimum logic utilizing mere 340 slices and 22 adders. Moreover, this design meets the real time constraints of different video/image coders and peak-signal-to-noise-ratio (PSNR) requirements. Furthermore, the proposed technique has significant advantages over recent well-known methods along with accuracy in terms of power reduction, silicon area usage, and maximum operating frequency by 41%, 15%, and 15%, respectively. PMID:25133249

  8. A physics-based compact model of ferroelectric tunnel junction for memory and logic design

    NASA Astrophysics Data System (ADS)

    Wang, Zhaohao; Zhao, Weisheng; Kang, Wang; Bouchenak-Khelladi, Anes; Zhang, Yue; Zhang, Youguang; Klein, Jacques-Olivier; Ravelosona, Dafiné; Chappert, Claude

    2014-01-01

    Ferroelectric tunnel junction (FTJ) is able to store non-volatile data in the spontaneous polarization direction of ferroelectric tunnel barrier. Recent progress has demonstrated its great potential to build up the next generation non-volatile memory and logic (NVM and NVL) thanks to the high OFF/ON resistance ratio, fast operation speed, low write power, non-destructive readout and so on. In this paper, we present the first physics-based compact model for Co/BTO/LSMO FTJ nanopillar, which was reported experimentally to exhibit excellent NVM performance. This model integrates related physical models of tunnel resistance, static switching voltage and dynamic switching delay. Its accuracy is shown by the good agreement between numerical model simulation and experimental measurements. This compact model has been developed in Verilog-A language and validated by single-cell simulation on Cadence Virtuoso Platform. Hybrid simulations based on 40 nm-technology node of FTJ memory arrays and non-volatile full adder were performed to demonstrate the efficiency of our compact model for the simulation and analysis of CMOS/FTJ integrated circuits.

  9. Design and implementation of low power clock gated 64-bit ALU on ultra scale FPGA

    NASA Astrophysics Data System (ADS)

    Gupta, Ashutosh; Murgai, Shruti; Gulati, Anmol; Kumar, Pradeep

    2016-03-01

    64-bit energy efficient Arithmetic and Logic Unit using negative latch based clock gating technique is designed in this paper. The 64-bit ALU is designed using multiplexer based full adder cell. We have designed a 64-bit ALU with a gated clock. We have used negative latch based circuit for generating gated clock. This gated clock is used to control the multiplexer based 64-bit ALU. The circuit has been synthesized on kintex FPGA through Xilinx ISE Design Suite 14.7 using 28 nm technology in Verilog HDL. The circuit has been simulated on Modelsim 10.3c. The design is verified using System Verilog on QuestaSim in UVM environment. We have achieved 74.07%, 92. 93% and 95.53% reduction in total clock power, 89.73%, 91.35% and 92.85% reduction in I/Os power, 67.14%, 62.84% and 74.34% reduction in dynamic power and 25.47%, 29.05% and 46.13% reduction in total supply power at 20 MHz, 200 MHz and 2 GHz frequency respectively. The power has been calculated using XPower Analyzer tool of Xilinx ISE Design Suite 14.3.

  10. A multi coding technique to reduce transition activity in VLSI circuits

    NASA Astrophysics Data System (ADS)

    Vithyalakshmi, N.; Rajaram, M.

    2014-02-01

    Advances in VLSI technology have enabled the implementation of complex digital circuits in a single chip, reducing system size and power consumption. In deep submicron low power CMOS VLSI design, the main cause of energy dissipation is charging and discharging of internal node capacitances due to transition activity. Transition activity is one of the major factors that also affect the dynamic power dissipation. This paper proposes power reduction analyzed through algorithm and logic circuit levels. In algorithm level the key aspect of reducing power dissipation is by minimizing transition activity and is achieved by introducing a data coding technique. So a novel multi coding technique is introduced to improve the efficiency of transition activity up to 52.3% on the bus lines, which will automatically reduce the dynamic power dissipation. In addition, 1 bit full adders are introduced in the Hamming distance estimator block, which reduces the device count. This coding method is implemented using Verilog HDL. The overall performance is analyzed by using Modelsim and Xilinx Tools. In total 38.2% power saving capability is achieved compared to other existing methods.

  11. A new approach in dry technology for non-degrading optical and EUV mask cleaning

    NASA Astrophysics Data System (ADS)

    Varghese, Ivin; Smith, Ben; Balooch, Mehdi; Bowers, Chuck

    2012-11-01

    The Eco-Snow Systems group of RAVE N.P., Inc. has developed a new cleaning technique to target several of the advanced and next generation mask clean challenges. This new technique, especially when combined with Eco-Snow Systems cryogenic CO2 cleaning technology, provides several advantages over existing methods because it: 1) is solely based on dry technique without requiring additional complementary aggressive wet chemistries that degrade the mask, 2) operates at atmospheric pressure and therefore avoids expensive and complicated equipment associated with vacuum systems, 3) generates ultra-clean reactants eliminating possible byproduct adders, 4) can be applied locally for site specific cleaning without exposing the rest of the mask or can be used to clean the entire mask, 5) removes organic as well as inorganic particulates and film contaminations, and 6) complements current techniques utilized for cleaning of advanced masks such as reduced chemistry wet cleans. In this paper, we shall present examples demonstrating the capability of this new technique for removal of pellicle glue residues and for critical removal of carbon contamination on EUV masks.

  12. The cometary biosphere and the origin of life

    NASA Astrophysics Data System (ADS)

    Sheldon, Robert B.

    2011-10-01

    The Origin-of-Life (OOL) is defined as an information threshold and compared to the Shannon information of the universe. It is shown that the information content of a minimally viable cell must be greater than the capabilities of the universe to calculate with a random search, and must therefore include coherence. Since No-Free-Lunch theorems argue that there are no better algorithms than random searches, we eliminate several alternate theories of OOL that rely on "smart" algorithms, including the anti-entropic "luck" solution. Then high negentropy states can only be achieved by coherent addition of pre-existing negentropy via some low-entropy mechanism. Since most cosmologists believe information is conserved, it is shown that the addition of information corresponds to a flow of information through Fourier space from large to small scales. The requirements on the information "adder" for low temporal entropy, high spatial coherence, rapid coherent addition, and dense Fourier space flow, are shown to be met by comets. We close with a speculation that the fractal dimension of the galactic matter distributed through the cosmos may reveal the details of a dark matter origin in comets.

  13. An Innovative Compiler For Programming And Designing Real-Time Signal Processors

    NASA Astrophysics Data System (ADS)

    Petruschka, Orni; Torng, H. C.

    1986-04-01

    Real time signal processing tasks impose stringent requirements on computing systems. One approach to satisfying these demands is to employ intelligently interconnected multiple arithmetic units, such as multipliers, adders, logic units and others, to implement concurrent computations. Two problems emerge: 1) Programming: Programs with wide instruction words have to be developed to exercise the multiple arithmetic units fully and efficiently to meet the real-time processing loads; 2) Design: With a given set of real-time signal processing tasks, design procedures are needed to specify multiple arithmetic units and their interconnection schemes for the processor. This paper presents a compiler which provides a solution to the programming and design problems. The compiler that has been developed translates blocks of RISC-like instructions into programs of wide microinstructions; each of these microinstructions initiates many concurrently executable operations. In so doing, we seek to achieve the maximum utilization of execution resources and to complete processing tasks in minimum time. The compiler is based on an innovative "Dispatch Stack" concept, and has been applied to program Floating Point System(FPS) processors; the resulting program for computing inner-product and other signal processing tasks are as good as those obtained by laborious hand-compilation. We will then show that the compiler developed for programming can be used advantageously to design real-time signal processing systems with multiple arithmetic units.

  14. A learnable parallel processing architecture towards unity of memory and computing.

    PubMed

    Li, H; Gao, B; Chen, Z; Zhao, Y; Huang, P; Ye, H; Liu, L; Liu, X; Kang, J

    2015-08-14

    Developing energy-efficient parallel information processing systems beyond von Neumann architecture is a long-standing goal of modern information technologies. The widely used von Neumann computer architecture separates memory and computing units, which leads to energy-hungry data movement when computers work. In order to meet the need of efficient information processing for the data-driven applications such as big data and Internet of Things, an energy-efficient processing architecture beyond von Neumann is critical for the information society. Here we show a non-von Neumann architecture built of resistive switching (RS) devices named "iMemComp", where memory and logic are unified with single-type devices. Leveraging nonvolatile nature and structural parallelism of crossbar RS arrays, we have equipped "iMemComp" with capabilities of computing in parallel and learning user-defined logic functions for large-scale information processing tasks. Such architecture eliminates the energy-hungry data movement in von Neumann computers. Compared with contemporary silicon technology, adder circuits based on "iMemComp" can improve the speed by 76.8% and the power dissipation by 60.3%, together with a 700 times aggressive reduction in the circuit area.

  15. Boolean gates on actin filaments

    NASA Astrophysics Data System (ADS)

    Siccardi, Stefano; Tuszynski, Jack A.; Adamatzky, Andrew

    2016-01-01

    Actin is a globular protein which forms long polar filaments in the eukaryotic cytoskeleton. Actin networks play a key role in cell mechanics and cell motility. They have also been implicated in information transmission and processing, memory and learning in neuronal cells. The actin filaments have been shown to support propagation of voltage pulses. Here we apply a coupled nonlinear transmission line model of actin filaments to study interactions between voltage pulses. To represent digital information we assign a logical TRUTH value to the presence of a voltage pulse in a given location of the actin filament, and FALSE to the pulse's absence, so that information flows along the filament with pulse transmission. When two pulses, representing Boolean values of input variables, interact, then they can facilitate or inhibit further propagation of each other. We explore this phenomenon to construct Boolean logical gates and a one-bit half-adder with interacting voltage pulses. We discuss implications of these findings on cellular process and technological applications.

  16. Recent advances in the development of high average power induction accelerators for industrial and environmental applications

    SciTech Connect

    Neau, E.L.

    1994-09-01

    Short-pulse accelerator technology developed during the early 1960`s through the late 1980`s is being extended to high average power systems capable of use in industrial and environmental applications. Processes requiring high dose levels and/or high volume throughput will require systems with beam power levels from several hundreds of kilowatts to megawatts. Beam accelerating potentials can range from less than 1 MeV to as much as 10 MeV depending on the type of beam, depth of penetration required, and the density of the product being treated. This paper addresses the present status of a family of high average power systems, with output beam power levels up to 200 kW, now in operation that use saturable core switches to achieve output pulse widths of 50 to 80 nanoseconds. Inductive adders and field emission cathodes are used to generate beams of electrons or x-rays at up to 2.5 MeV over areas of 1000 cm{sup 2}. Similar high average power technology is being used at {le} 1 MeV to drive repetitive ion beam sources for treatment of material surfaces over 100`s of cm{sup 2}.

  17. Challenges in constructing EUV metrology tools to qualify the EUV masks for HVM implementation

    NASA Astrophysics Data System (ADS)

    Houser, David C.; Dong, Feng; Perera, Chami N.; Perera, Rupert C. C.

    2015-09-01

    Extreme Ultraviolet (EUV) Lithography is still viewed as the most promising approach for maintaining the pace of Moore's Law. Recent real achievements in EUV Lithography (EUVL) have encouraged semiconductor manufacturers to reconsider their road maps. One of the principal challenges in the ongoing EUVL implementation for high volume manufacturing (HVM) is the availability of necessary clean at wavelength metrology tools. EUV Tech is the world's leading manufacturer of at-wavelength EUV metrology equipment. Founded in 1997, EUV Tech has pioneered the development of several stand-alone inspection, metrology, and calibration tools for EUV lithographic applications that can be operated in a clean room environment on the floor of a fab. In this paper, EUV Tech's R&D program to minimize particle adders in our EUV Reflectometer along with the ongoing effort to enhance the reflectivity and wavelength, precision and accuracy required to qualify the EUV masks for HVM. In addition to preliminary results from our stand alone EUV Scatterometer developed to characterize the phase roughness of a EUV mask and the introduction of EUV Tech's Pellicle test suite for testing EUV pellicles.

  18. Design of efficient circularly symmetric two-dimensional variable digital FIR filters.

    PubMed

    Bindima, Thayyil; Elias, Elizabeth

    2016-05-01

    Circularly symmetric two-dimensional (2D) finite impulse response (FIR) filters find extensive use in image and medical applications, especially for isotropic filtering. Moreover, the design and implementation of 2D digital filters with variable fractional delay and variable magnitude responses without redesigning the filter has become a crucial topic of interest due to its significance in low-cost applications. Recently the design using fixed word length coefficients has gained importance due to the replacement of multipliers by shifters and adders, which reduces the hardware complexity. Among the various approaches to 2D design, transforming a one-dimensional (1D) filter to 2D by transformation, is reported to be an efficient technique. In this paper, 1D variable digital filters (VDFs) with tunable cut-off frequencies are designed using Farrow structure based interpolation approach, and the sub-filter coefficients in the Farrow structure are made multiplier-less using canonic signed digit (CSD) representation. The resulting performance degradation in the filters is overcome by using artificial bee colony (ABC) optimization. Finally, the optimized 1D VDFs are mapped to 2D using generalized McClellan transformation resulting in low complexity, circularly symmetric 2D VDFs with real-time tunability.

  19. A new architecture of current-mode CMOS TDI Sensor

    NASA Astrophysics Data System (ADS)

    Ji, Cheng; Chen, Yongping

    2015-10-01

    Nowadays, CMOS sensors still suffer from the problem of low SNR, especially in the stage of low illumination and high relative scanning velocity. Lots of methods have been develop to overcome this problem. Among these researches, TDI (Time Delay Integration) architecture is a more natural choice, which is natively supported by CCD sensors. In this paper a new kind of proposed current-mode sensor is used to achieve TDI operation in analog domain. The circuit is composed of three main parts. At first, a current-type pixel is proposed, in which the active MOSFET is operated in the triode region to ensure the output current is linearly dependent on the gate voltage and avoid the reduction of threshold voltage in the traditional voltage mode pixels, such as 3T, 4T which use the source followers as its active part. Then a discrete double sampling (DDS) unit, which is operated in the form of currents is used to efficiently reduce the fixed pattern noise (FPN) and make the output is independent of reset voltage of pixels. For accumulation, an improved current mirror adder under controlled of timing circuits is proposed to overcome the problem of saturation suffered in voltage domain. Some main noise sources, especially come from analog sample and holds capacitors and switches is analyzed. Finally, simulation results with CSMC 0.5um technology and Cadence IC show that the proposed method is reasonable and efficient to improve the SNR.

  20. E-beam inspection of EUV mask defects: To etch or not to etch?

    NASA Astrophysics Data System (ADS)

    Bonam, Ravi; Tien, Hung-Yu; Park, Chanro; Halle, Scott; Wang, Fei; Corliss, Daniel; Fang, Wei; Jau, Jack

    2014-04-01

    EUV Lithography is aimed to be inserted into mainstream production for sub-20nm pattern fabrication. Unlike conventional optical lithography, frequent defectivity monitors (adders, repeaters etc.) are required in EUV lithography. Due to sub-20nm pattern and defect dimensions e-beam inspection of critical pattern areas is essential for yield monitor. In previous work we showed sub-10nm defect detection sensitivity1 on patterned resist wafers. In this work we report 8-10× improvement in scan rates of etched patterns compared to resist patterns without loss in defect detection sensitivity. We observed good etch transfer of sub-10nm resist features. A combination of smart scan strategies with improved etched pattern scan rates can further improve throughput of e-beam inspection. An EUV programmed defect mask with Line/Space, Contact patterns was used to evaluate printability of defects and defect detection (Die-Die and Die-Database) capability of the e-beam inspection tool. Defect inspection tool parameters such as averaging, threshold value were varied to assess its detection capability and were compared to previously obtained results on resist patterns.

  1. Evaluation of a gamma camera system for the RITS-6 accelerator using the self-magnetic pinch diode

    NASA Astrophysics Data System (ADS)

    Webb, Timothy J.; Kiefer, Mark L.; Gignac, Raymond; Baker, Stuart A.

    2015-08-01

    The self-magnetic pinch (SMP) diode is an intense radiographic source fielded on the Radiographic Integrated Test Stand (RITS-6) accelerator at Sandia National Laboratories in Albuquerque, NM. The accelerator is an inductive voltage adder (IVA) that can operate from 2-10 MV with currents up to 160 kA (at 7 MV). The SMP diode consists of an annular cathode separated from a flat anode, holding the bremsstrahlung conversion target, by a vacuum gap. Until recently the primary imaging diagnostic utilized image plates (storage phosphors) which has generally low DQE at these photon energies along with other problems. The benefits of using image plates include a high-dynamic range, good spatial resolution, and ease of use. A scintillator-based X-ray imaging system or "gamma camera" has been fielded in front of RITS and the SMP diode which has been able to provide vastly superior images in terms of signal-to-noise with similar resolution and acceptable dynamic range.

  2. In-Situ Anode Heating and Its Effects on Atomic Constituents in the A-K Gap in Self-Magnetic Pinch (SMP) Experiments

    NASA Astrophysics Data System (ADS)

    Simpson, Sean; Renk, Timothy; Johnston, Mark; Mazarakis, Mike; Patel, Sonal

    2015-11-01

    The RITS-6 inductive voltage adder (IVA) accelerator (3.5-8.5 MeV) at Sandia National Laboratories produces high-power (TW) focused electron beams (<3mm diameter) for flash x-ray radiography applications. The Self-Magnetic Pinch (SMP) diode utilizes a hollowed metal cathode to produce a pinched focus onto a high-Z metal anode converter. There is not a clear understanding as to the effects various contaminants such as C, CO, H, H2O, HmCn, O2, and N2, on the anode surface or in the bulk may have on impedance dynamics, beam stability, beam spot size, and reproducibility. Heating pure Ta anodes with and without a thin Al coating have been investigated using temperatures ranging from 400 °C to 1000 °C. Initial experiments indicate a significant reduction in H and C as seen in high-speed spectral analysis of plasmas at the converter and a reduction in the back-streaming proton current. Experiments are ongoing, and latest results will be reported. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.

  3. Impedance Dynamics in the Self-Magnetic Pinch (SMP) Diode on the RITS-6 Accelerator

    NASA Astrophysics Data System (ADS)

    Renk, Timothy; Johnston, Mark; Leckbee, Joshua; Webb, Timothy; Mazarakis, Michael; Kiefer, Mark; Bennett, Nichelle

    2014-10-01

    The RITS-6 inductive voltage adder (IVA) accelerator (3.5-8.5 MeV) at Sandia National Laboratories produces high-power (TW) focused electron beams (<3 mm diameter) for flash x-ray radiography applications. The Self-Magnetic Pinch (SMP) diode utilizes a hollowed metal cathode to produce a pinched focus onto a high Z metal converter. The electron flow from the IVA driver into the load region complicates understanding of diode evolution. There is growing evidence that reducing cathode size below some ``optimum'' value in order to achieve desired spot size reduction results in pinch instabilities leading to either reduced dose-rate, early radiation power termination, or both. We are studying evolving pinch dynamics with current and x-ray monitors, optical diagnostics, and spectroscopy, as well as with LSP [1] code simulations. We are also planning changes to anode-cathode materials as well as changes to the diode aspect ratio in an attempt to mitigate the above trends and improve pinch stability while achieving simultaneous spot size reduction. Experiments are ongoing, and latest results will be reported [1]. LSP is a software product of ATK Mission Research, Albuquerque, NM. Sandia National Laboratories is a multiprogram laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Adminis-tration under Contract DE-AC04-94AL85000.

  4. Mixed Source Interrogation of Steel Shielded Special Nuclear Material Using an Intense Pulsed Source

    NASA Astrophysics Data System (ADS)

    Hill, C.; Clemett, C. D.; Campbell, B.; Martin, P. N.; Threadgold, J.; O'Malley, J.

    This paper explores the benefits of using a mixed photon and neutron radiation source for active detection of special nuclear material. More than fifty irradiations were performed using an 8 MV electron accelerator employing and induction voltage adder (IVA). The experiments used a high atomic number converter to produce a Bremsstrahlung photon spectrum which was then used to create a neutron source via a nuclear interaction with heavy water (deuterium oxide, D2O). This mixed particle source was used to irradiate a depleted uranium (DU) sample, inducing fission in the sample. Several thicknesses of steel shielding were tested in order to compare the performance of the mixed photon and neutron source to a Bremsstrahlung-only source. An array of detectors were fielded to record both photons and neutrons emitted by the fission reactions. A correlation between steel shielding and a detection figure-of-merit can be seen in all cases where the Bremsstrahlung-only source was used. The same relationship for the mixed photon-neutron source is less consistent. The data collected from the fielded detectors is compared to MCNP6 calculations and good agreement is found.

  5. Performance analysis of a complete adiabatic logic system driven by the proposed power clock generator

    NASA Astrophysics Data System (ADS)

    Kanungo, Jitendra; Dasgupta, S.

    2014-09-01

    We analyze the energy performance of a complete adiabatic circuit/system including the Power Clock Generator (PCG) at the 90 nm CMOS technology node. The energy performance in terms of the conversion efficiency of the PCG is extensively carried out under the variations of supply voltage, process corner and the driver transistor's width. We propose an energy-efficient singe cycle control circuit based on the two-stage comparator for the synchronous charge recovery sinusoidal power clock generator (PCG). The proposed PCG is used to drive the 4-bit adiabatic Ripple Carry Adder (RCA) and their simulation results are compared with the adiabatic RCA driven by the reported PCG. We have also simulated the logically equivalent static CMOS RCA circuit to compare the energy saving of adiabatic and non-adiabatic logic circuits. In the clock frequency range from 25 MHz to 1GHz, the proposed PCG gives a maximum conversion efficiency of 56.48%. This research work shows how the design of an efficient PCG increases the energy saving of adiabatic logic.

  6. Integrated cleaning and handling automation of NXE3100 reticles

    NASA Astrophysics Data System (ADS)

    Jonckheere, Rik; Waehler, Tobias; Baudemprez, Bart; Dietze, Uwe; Dress, Peter; Brux, Oliver; Ronse, Kurt

    2012-02-01

    This paper focuses on imec's activities to minimize particle contamination on reticles (front- and backside) for the latest EUVL scanner, i.e. the NXE3100. Mask cleaning is performed on the HamaTech MaskTrack Pro® (MTP). Although also front-side particles and other contamination are being tackled by cleaning, the prime purpose is the avoidance of back-side particles which would lead to unacceptable overlay performance of the scanner and hence create yield loss, as well as cause unscheduled scanner down situations for cleaning of the reticle clamp. In the absence of a soft pellicle, the present approach to minimize particle adders during handling is to load EUV reticles into the scanner via so-called dual pods. The inner pod as such acts as a removable hard pellicle. Through the installation of the HamaTech MaskTrack Pro InSync® tool, interfaced to the MaskTrack Pro Cleaner, automated handling of EUV reticles in such pods is enabled. This integrated solution for handling and storage is additionally being equipped with an integrated reticle back-side inspection capability.

  7. High precision computing with charge domain devices and a pseudo-spectral method therefor

    NASA Technical Reports Server (NTRS)

    Barhen, Jacob (Inventor); Toomarian, Nikzad (Inventor); Fijany, Amir (Inventor); Zak, Michail (Inventor)

    1997-01-01

    The present invention enhances the bit resolution of a CCD/CID MVM processor by storing each bit of each matrix element as a separate CCD charge packet. The bits of each input vector are separately multiplied by each bit of each matrix element in massive parallelism and the resulting products are combined appropriately to synthesize the correct product. In another aspect of the invention, such arrays are employed in a pseudo-spectral method of the invention, in which partial differential equations are solved by expressing each derivative analytically as matrices, and the state function is updated at each computation cycle by multiplying it by the matrices. The matrices are treated as synaptic arrays of a neural network and the state function vector elements are treated as neurons. In a further aspect of the invention, moving target detection is performed by driving the soliton equation with a vector of detector outputs. The neural architecture consists of two synaptic arrays corresponding to the two differential terms of the soliton-equation and an adder connected to the output thereof and to the output of the detector array to drive the soliton equation.

  8. Plasmonic-multimode-interference-based logic circuit with simple phase adjustment

    PubMed Central

    Ota, Masashi; Sumimura, Asahi; Fukuhara, Masashi; Ishii, Yuya; Fukuda, Mitsuo

    2016-01-01

    All-optical logic circuits using surface plasmon polaritons have a potential for high-speed information processing with high-density integration beyond the diffraction limit of propagating light. However, a number of logic gates that can be cascaded is limited by complicated signal phase adjustment. In this study, we demonstrate a half-adder operation with simple phase adjustment using plasmonic multimode interference (MMI) devices, composed of dielectric stripes on a metal film, which can be fabricated by a complementary metal-oxide semiconductor (MOS)-compatible process. Also, simultaneous operations of XOR and AND gates are substantiated experimentally by combining 1 × 1 MMI based phase adjusters and 2 × 2 MMI based intensity modulators. An experimental on-off ratio of at least 4.3 dB is confirmed using scanning near-field optical microscopy. The proposed structure will contribute to high-density plasmonic circuits, fabricated by complementary MOS-compatible process or printing techniques. PMID:27086694

  9. Design of efficient circularly symmetric two-dimensional variable digital FIR filters

    PubMed Central

    Bindima, Thayyil; Elias, Elizabeth

    2016-01-01

    Circularly symmetric two-dimensional (2D) finite impulse response (FIR) filters find extensive use in image and medical applications, especially for isotropic filtering. Moreover, the design and implementation of 2D digital filters with variable fractional delay and variable magnitude responses without redesigning the filter has become a crucial topic of interest due to its significance in low-cost applications. Recently the design using fixed word length coefficients has gained importance due to the replacement of multipliers by shifters and adders, which reduces the hardware complexity. Among the various approaches to 2D design, transforming a one-dimensional (1D) filter to 2D by transformation, is reported to be an efficient technique. In this paper, 1D variable digital filters (VDFs) with tunable cut-off frequencies are designed using Farrow structure based interpolation approach, and the sub-filter coefficients in the Farrow structure are made multiplier-less using canonic signed digit (CSD) representation. The resulting performance degradation in the filters is overcome by using artificial bee colony (ABC) optimization. Finally, the optimized 1D VDFs are mapped to 2D using generalized McClellan transformation resulting in low complexity, circularly symmetric 2D VDFs with real-time tunability. PMID:27222739

  10. MHz repetition rate solid-state driver for high current induction accelerators

    SciTech Connect

    Brooksby, C; Caporaso, G; Goerz, D; Hanks, R; Hickman, B; Kirbie, H; Lee, B; Saethre, R

    1999-03-01

    A research team from the Lawrence Livermore National Laboratory and Bechtel Nevada Corporation is developing an all solid-state power source for high current induction accelerators. The original power system design, developed for heavy-ion fusion accelerators, is based on the simple idea of using an array of field effect transistors to switch energy from a pre-charged capacitor bank to an induction accelerator cell. Recently, that idea has been expanded to accommodate the greater power needs of a new class of high-current electron accelerators for advanced radiography. For this purpose, we developed a 3-stage induction adder that uses over 4,000 field effect transistors to switch peak voltages of 45 kV at currents up to 4.8 kA with pulse repetition rates of up to 2 MHz. This radically advanced power system can generate a burst of five or more pulses that vary from 200 ns to 2 µs at a duty cycle of up to 25%. Our new source is precise, robust, flexible, and exceeds all previous drivers for induction machines by a factor of 400 in repetition rate and a factor of 1000 in duty cycle.

  11. A learnable parallel processing architecture towards unity of memory and computing.

    PubMed

    Li, H; Gao, B; Chen, Z; Zhao, Y; Huang, P; Ye, H; Liu, L; Liu, X; Kang, J

    2015-01-01

    Developing energy-efficient parallel information processing systems beyond von Neumann architecture is a long-standing goal of modern information technologies. The widely used von Neumann computer architecture separates memory and computing units, which leads to energy-hungry data movement when computers work. In order to meet the need of efficient information processing for the data-driven applications such as big data and Internet of Things, an energy-efficient processing architecture beyond von Neumann is critical for the information society. Here we show a non-von Neumann architecture built of resistive switching (RS) devices named "iMemComp", where memory and logic are unified with single-type devices. Leveraging nonvolatile nature and structural parallelism of crossbar RS arrays, we have equipped "iMemComp" with capabilities of computing in parallel and learning user-defined logic functions for large-scale information processing tasks. Such architecture eliminates the energy-hungry data movement in von Neumann computers. Compared with contemporary silicon technology, adder circuits based on "iMemComp" can improve the speed by 76.8% and the power dissipation by 60.3%, together with a 700 times aggressive reduction in the circuit area. PMID:26271243

  12. Study on AC-DC Electrical Conductivities in Warm Dense Matter Generated by Pulsed-power Discharge with Isochoric Vessel

    NASA Astrophysics Data System (ADS)

    Sasaki, Toru; Ohuchi, Takumi; Takahashi, Takuya; Kawaguchi, Yoshinari; Saito, Hirotaka; Miki, Yasutoshi; Takahashi, Kazumasa; Kikuchi, Takashi; Aso, Tsukasa; Harada, Nob.

    2016-03-01

    To observe AC and DC electrical conductivity in warm dense matter (WDM), we have demonstrated to apply the spectroscopic ellipsometry for a pulsed-power discharge with isochoric vessel. At 10 μs from the beginning of discharge, the generated parameters by using pulsed-power discharge with isochoric vessel are 0.1 ρ s (ρ s: solid density) of density and 4000 K of temperature, respectively. The DC electrical conductivity for above parameters is estimated to be 104 S/m. In order to measure the AC electrical conductivity, we have developed a four-detector spectroscopic ellipsometer with a multichannel spectrometer. The multichannel spectrometer, in which consists of a 16-channel photodiode array, a two-stages voltage adder, and a flat diffraction grating, has 10 MHz of the frequency response with covered visible spectrum. For applying the four-detector spectroscopic ellipsometer, we observe the each observation signal evolves the polarized behavior compared to the ratio as I 1/I 2.

  13. Highly Uniform Carbon Nanotube Field-Effect Transistors and Medium Scale Integrated Circuits.

    PubMed

    Chen, Bingyan; Zhang, Panpan; Ding, Li; Han, Jie; Qiu, Song; Li, Qingwen; Zhang, Zhiyong; Peng, Lian-Mao

    2016-08-10

    Top-gated p-type field-effect transistors (FETs) have been fabricated in batch based on carbon nanotube (CNT) network thin films prepared from CNT solution and present high yield and highly uniform performance with small threshold voltage distribution with standard deviation of 34 mV. According to the property of FETs, various logical and arithmetical gates, shifters, and d-latch circuits were designed and demonstrated with rail-to-rail output. In particular, a 4-bit adder consisting of 140 p-type CNT FETs was demonstrated with higher packing density and lower supply voltage than other published integrated circuits based on CNT films, which indicates that CNT based integrated circuits can reach to medium scale. In addition, a 2-bit multiplier has been realized for the first time. Benefitted from the high uniformity and suitable threshold voltage of CNT FETs, all of the fabricated circuits based on CNT FETs can be driven by a single voltage as small as 2 V.

  14. A review of accelerator concepts for the Advanced Hydrotest Facility

    SciTech Connect

    Toepfer, A.J.

    1998-08-01

    The Advanced Hydrotest Facility (AHF) is a facility under consideration by the Department of Energy (DOE) for conducting explosively-driven hydrodynamic experiments. The major diagnostic tool at AHF will be a radiography accelerator having radiation output capable of penetrating very dense dynamic objects on multiple viewing axes with multiple pulses on each axis, each pulse having a time resolution capable of freezing object motion ({approx}50-ns) and achieving a spatial resolution {approx}1 mm at the object. Three accelerator technologies are being considered for AHF by the DOE national laboratories at Los Alamos (LANL), Livermore (LLNL), and Sandia (SNL). Two of these are electron accelerators that will produce intense x-ray pulses from a converter target yielding a dose {approx}1,000--2,000 Rads {at} 1 meter. LLNL has proposed a 16--20 MeV, 3--6 kA linear induction accelerator (LIA) driven by FET-switched modulators driving metglas loaded cavities. SNL has proposed a 12-MeV, 40-kA Inductive Voltage Adder (IVA) accelerator based on HERMES III pulsed power technology. The third option is a 25--50-GeV proton accelerator capable of {approx}10{sup 13} protons/pulse proposed by LANL. This paper will review the current status of the three accelerator concepts for AHF.

  15. Hybrid VLSI/QCA Architecture for Computing FFTs

    NASA Technical Reports Server (NTRS)

    Fijany, Amir; Toomarian, Nikzad; Modarres, Katayoon; Spotnitz, Matthew

    2003-01-01

    A data-processor architecture that would incorporate elements of both conventional very-large-scale integrated (VLSI) circuitry and quantum-dot cellular automata (QCA) has been proposed to enable the highly parallel and systolic computation of fast Fourier transforms (FFTs). The proposed circuit would complement the QCA-based circuits described in several prior NASA Tech Briefs articles, namely Implementing Permutation Matrices by Use of Quantum Dots (NPO-20801), Vol. 25, No. 10 (October 2001), page 42; Compact Interconnection Networks Based on Quantum Dots (NPO-20855) Vol. 27, No. 1 (January 2003), page 32; and Bit-Serial Adder Based on Quantum Dots (NPO-20869), Vol. 27, No. 1 (January 2003), page 35. The cited prior articles described the limitations of very-large-scale integrated (VLSI) circuitry and the major potential advantage afforded by QCA. To recapitulate: In a VLSI circuit, signal paths that are required not to interact with each other must not cross in the same plane. In contrast, for reasons too complex to describe in the limited space available for this article, suitably designed and operated QCAbased signal paths that are required not to interact with each other can nevertheless be allowed to cross each other in the same plane without adverse effect. In principle, this characteristic could be exploited to design compact, coplanar, simple (relative to VLSI) QCA-based networks to implement complex, advanced interconnection schemes.

  16. A 6 kV arbitrary waveform generator for the Tevatron Electron Lens

    SciTech Connect

    Pfeffer, H.; Saewert, G.

    2011-11-09

    This paper reports on a 6 kV modulator built and installed at Fermilab to drive the electron gun anode for the Tevatron Electron Lens (TEL). The TEL was built with the intention of shifting the individual (anti)proton bunch tunes to even out the tune spread among all 36 bunches with the desire of improving Tevatron integrated luminosity. This modulator is essentially a 6 kV arbitrary waveform generator that enables the TEL to define the electron beam intensity on a bunch-by-bunch basis. A voltage waveform is constructed having a 7 μs duration that corresponds to the tune shift requirements of a 12-bunch (anti)proton beam pulse train. This waveform is played out for any one or all three bunch trains in the Tevatron. The programmed waveform voltages transition to different levels at time intervals corresponding to the 395 ns bunch spacing. In addition, complex voltage waveforms can be played out at a sustained rate of 143 kHz over the full 6 kV output range. This paper describes the novel design of the inductive adder topology employing five transformers. It describes the design aspects that minimize switching losses for this multi-kilovolt, high repetition rate and high duty factor application.

  17. Plasmonic-multimode-interference-based logic circuit with simple phase adjustment

    NASA Astrophysics Data System (ADS)

    Ota, Masashi; Sumimura, Asahi; Fukuhara, Masashi; Ishii, Yuya; Fukuda, Mitsuo

    2016-04-01

    All-optical logic circuits using surface plasmon polaritons have a potential for high-speed information processing with high-density integration beyond the diffraction limit of propagating light. However, a number of logic gates that can be cascaded is limited by complicated signal phase adjustment. In this study, we demonstrate a half-adder operation with simple phase adjustment using plasmonic multimode interference (MMI) devices, composed of dielectric stripes on a metal film, which can be fabricated by a complementary metal-oxide semiconductor (MOS)-compatible process. Also, simultaneous operations of XOR and AND gates are substantiated experimentally by combining 1 × 1 MMI based phase adjusters and 2 × 2 MMI based intensity modulators. An experimental on-off ratio of at least 4.3 dB is confirmed using scanning near-field optical microscopy. The proposed structure will contribute to high-density plasmonic circuits, fabricated by complementary MOS-compatible process or printing techniques.

  18. Defectivity and particle reduction for mask life extension, and imprint mask replication for high-volume semiconductor manufacturing

    NASA Astrophysics Data System (ADS)

    Emoto, Keiji; Sakai, Fumio; Sato, Chiaki; Takabayashi, Yukio; Nakano, Hitoshi; Takabayashi, Tsuneo; Yamamoto, Kiyohito; Hattori, Tadashi; Hiura, Mitsuru; Ando, Toshiaki; Kawanobe, Yoshio; Azuma, Hisanobu; Iwanaga, Takehiko; Choi, Jin; Aghili, Ali; Jones, Chris; Irving, J. W.; Fletcher, Brian; Ye, Zhengmao

    2016-03-01

    Imprint lithography has been shown to be an effective technique for replication of nano-scale features. Jet and Flash* Imprint Lithography (J-FIL*) involves the field-by-field deposition and exposure of a low viscosity resist deposited by jetting technology onto the substrate. The patterned mask is lowered into the fluid which then quickly flows into the relief patterns in the mask by capillary action. Following this filling step, the resist is crosslinked under UV radiation, and then the mask is removed, leaving a patterned resist on the substrate. Criteria specific to any lithographic process for the semiconductor industry include overlay, throughput and defectivity. The purpose of this paper is to describe the technology advancements made in the reduction of particle adders in an imprint tool and introduce the new mask replication tool that will enable the fabrication of replica masks with added residual image placement errors suitable for memory devices with half pitches smaller than 15nm. Hard particles on a wafer or mask create the possibility of creating a permanent defect on the mask that can impact device yield and mask life. By using material methods to reduce particle shedding and by introducing an air curtain system, test stand results demonstrate the potential for extending mask life to better than 1000 wafers. Additionally, a new replication tool, the FPA-1100 NR2 is introduced. Mask chuck flatness simulation results were also performed and demonstrate that residual image placement errors can be reduced to as little as 1nm.

  19. Research on pinching characteristics of electron beams emitted from different cathode surfaces of a rod-pinch diode

    SciTech Connect

    Gao Yi; Qiu Aici; Zhang Zhong; Zhang Pengfei; Wang Zhiguo; Yang Hailiang

    2010-07-15

    The particle-in-cell code UNIPIC is used to simulate the working process of a rod-pinch diode and investigate the pinching characteristics of electron beams emitted from different cathode surfaces. The simulation results indicate that the electron beam emitted from the upstream surface pinches better than from other surfaces when all the three surfaces emit electrons. The charge-density deposition on the anode surface peaks at the rod tip while the deposited charge density is approximately uniform over the first 15 mm of the rod before rapidly increasing over the last 3 mm, indicating a large axial extent of electron deposition. For the case of single-surface emission, the pinching quality of the electron beam emitted from the downstream surface is better than those from other surfaces. The charge-density deposition peaks at the rod tip and decreases rapidly off the tip. Based on the relationship of Larmor radius, beam's self-magnetic field, and the spatial current distribution, the above simulation results are analyzed theoretically. The experiments are performed on the inductive voltage adder to examine the simulations. By comparing the axial distribution of the radiation on the anode rod measured with the pinhole camera and the on-axis forward x-ray dose measured with the LiF thermoluminescent detectors, the simulation results are verified. The electron emission suppression method and the impedance change for each case are investigated or discussed in this paper.

  20. A Double Precision High Speed Convolution Processor

    NASA Astrophysics Data System (ADS)

    Larochelle, F.; Coté, J. F.; Malowany, A. S.

    1989-11-01

    There exist several convolution processors on the market that can process images at video rate. However, none of these processors operates in floating point arithmetic. Unfortunately, many image processing algorithms presently under development are inoperable in integer arithmetic, forcing the researchers to use regular computers. To solve this problem, we designed a specialized convolution processor that operates in double precision floating point arithmetic with a throughput several thousand times faster than the one obtained on regular computer. Its high performance is attributed to a VLSI double precision convolution systolic cell designed in our laboratories. A 9X9 systolic array carries out, in a pipeline manner, every arithmetic operation. The processor is designed to interface directly with the VME Bus. A DMA chip is responsible for bringing the original pixel intensities from the memory of the computer to the systolic array and to return the convolved pixels back to memory. A special use of 8K RAMs allows an inexpensive and efficient way of delaying the pixel intensities in order to supply the right sequence to the systolic array. On board circuitry converts pixel values into floating point representation when the image is originally represented with integer values. An additional systolic cell, used as a pipeline adder at the output of the systolic array, offers the possibility of combining images together which allows a variable convolution window size and color image processing.

  1. A new interpolation arithmetic based readout signals process method for infrared imaging system applications

    NASA Astrophysics Data System (ADS)

    Li, Xinyi; Yao, Suying; Zhao, Yiqiang

    2009-07-01

    A new readout signals process circuit for infrared focal plane array (IR FPA) applications is proposed. In the proposed structure the continuous-time current signals from the detector array are mirrored, amplified, integrated on the integration capacitors and changed to discrete analog voltage signals. Next, these voltage signals are amplified and modulated by a group of encoded signals from the column buses, then fed to a multiple-input analog adder to generate a single serial output data stream. The generated single serial data stream is transferred to the mitigate noise circuit and is converted to digital signals by the A/D converter. For very large format detector arrays applications the speed restriction of the time-multiplexing circuitry and the A/D converter will be released. Since no scan technique has been used, all the output signals from an entire row in the detector array have been readout simultaneously without loss of optical power, the scalability of the photon-signals, the readout efficiency and the accuracy of the imaging system will be improved. Theory analysis and experimental results show that the proposed idea is reasonable and efficient. The proposed readout method is a solid option for large format infrared detector arrays and highly integrated infrared imaging system applications. In addition, the proposed idea also can be used for other active and passive imaging readout integrated circuits.

  2. A learnable parallel processing architecture towards unity of memory and computing

    PubMed Central

    Li, H.; Gao, B.; Chen, Z.; Zhao, Y.; Huang, P.; Ye, H.; Liu, L.; Liu, X.; Kang, J.

    2015-01-01

    Developing energy-efficient parallel information processing systems beyond von Neumann architecture is a long-standing goal of modern information technologies. The widely used von Neumann computer architecture separates memory and computing units, which leads to energy-hungry data movement when computers work. In order to meet the need of efficient information processing for the data-driven applications such as big data and Internet of Things, an energy-efficient processing architecture beyond von Neumann is critical for the information society. Here we show a non-von Neumann architecture built of resistive switching (RS) devices named “iMemComp”, where memory and logic are unified with single-type devices. Leveraging nonvolatile nature and structural parallelism of crossbar RS arrays, we have equipped “iMemComp” with capabilities of computing in parallel and learning user-defined logic functions for large-scale information processing tasks. Such architecture eliminates the energy-hungry data movement in von Neumann computers. Compared with contemporary silicon technology, adder circuits based on “iMemComp” can improve the speed by 76.8% and the power dissipation by 60.3%, together with a 700 times aggressive reduction in the circuit area. PMID:26271243

  3. Development of high frequency spice models for ferrite core inductors and transformers

    NASA Astrophysics Data System (ADS)

    Muyshondt, G. Patrick; Portnoy, William M.

    In this work high frequency SPICE models were developed to simulate the hysteresis and saturation effects of toroidal shaped ferrite core inductors and transformers. The models include the nonlinear, multi-valued B-H characteristic of the core material, leakage flux, stray capacitances, and core losses. The saturation effects were modeled using two diode clamping arrangements in conjunction with nonlinear dependent sources. Two possible controlling schemes were developed for the saturation switch. One of the arrangements used the current flowing through a series RC branch to control the switch, while the other used a NAND gate. The NAND gate implementation of the switch proved to be simpler and the parameters associated with it were easier to determine from the measurements and the B-H characteristics of the material. Lumped parameters were used to simulate the parasitic effects. Techniques for measuring these effects are described. The models were verified using manganese-zinc ferrite-type toroidal cores and they have general applicability to all circuit analysis codes equivalent function blocks such as multipliers, adders, and logic components.

  4. Interaction of toxic venoms with the complement system

    PubMed Central

    Birdsey, Vanessa; Lindorfer, Jean; Gewurz, H.

    1971-01-01

    Thirty-nine venoms from various vertebrate and invertebrate species were tested for their ability to consume haemolytic complement (C) activity upon incubation in fresh guinea-pig serum. Nineteen had `anti-complementary' activity, and these were provisionally sorted into the following groups: Pattern I—exemplified by the Naja haje (Egyptian cobra) and six other Elapidae species (all cobras), which induced selective consumption of C3—C9, and led to formation of a stable C3—C9-consuming intermediate; Pattern II—exemplified by the Agkistrodon rhodostoma (Malayan pit viper), Bitis arietans (puff adder), Bothrops jararaca (South American pit viper), Bothrops atrox (Fer de Lance) and three other species, which induced marked consumption of C4 and C2, as well as C3—C9, but did not form a stable C3—C9-consuming intermediate; and individual animals, e.g. the Lachesis muta (bushmaster), which induced other patterns (III—VI) of complement component consumption. Active fractions of representative venoms were partially purified by ion exchange and gel filtration chromatography and their interactions with the complement system characterized further. It is anticipated that these enzymes, with a capacity to activate the complement system in unique ways, will prove to be of further experimental usefulness. PMID:4398349

  5. Thermal management in high average power pulsed compression systems

    SciTech Connect

    Wavrik, R.W.; Reed, K.W.; Harjes, H.C.; Weber, G.J.; Butler, M.; Penn, K.J.; Neau, E.L.

    1992-08-01

    High average power repetitively pulsed compression systems offer a potential source of electron beams which may be applied to sterilization of wastes, treatment of food products, and other environmental and consumer applications. At Sandia National Laboratory, the Repetitive High Energy Pulsed Power (RHEPP) program is developing a 7 stage magnetic pulse compressor driving a linear induction voltage adder with an electron beam diode load. The RHEPP machine is being design to deliver 350 kW of average power to the diode in 60 ns FWHM, 2.5 MV, 3 kJ pulses at a repetition rate of 120 Hz. In addition to the electrical design considerations, the repetition rate requires thermal management of the electrical losses. Steady state temperatures must be kept below the material degradation temperatures to maximize reliability and component life. The optimum design is a trade off between thermal management, maximizing overall electrical performance of the system, reliability, and cost effectiveness. Cooling requirements and configurations were developed for each of the subsystems of RHEPP. Finite element models that combine fluid flow and heat transfer were used to screen design concepts. The analysis includes one, two, and three dimensional heat transfer using surface heat transfer coefficients and boundary layer models. Experiments were conducted to verify the models as well as to evaluate cooling channel fabrication materials and techniques in Metglas wound cores. 10 refs.

  6. Thermal management in high average power pulsed compression systems

    SciTech Connect

    Wavrik, R.W.; Reed, K.W.; Harjes, H.C.; Weber, G.J.; Butler, M.; Penn, K.J.; Neau, E.L.

    1992-01-01

    High average power repetitively pulsed compression systems offer a potential source of electron beams which may be applied to sterilization of wastes, treatment of food products, and other environmental and consumer applications. At Sandia National Laboratory, the Repetitive High Energy Pulsed Power (RHEPP) program is developing a 7 stage magnetic pulse compressor driving a linear induction voltage adder with an electron beam diode load. The RHEPP machine is being design to deliver 350 kW of average power to the diode in 60 ns FWHM, 2.5 MV, 3 kJ pulses at a repetition rate of 120 Hz. In addition to the electrical design considerations, the repetition rate requires thermal management of the electrical losses. Steady state temperatures must be kept below the material degradation temperatures to maximize reliability and component life. The optimum design is a trade off between thermal management, maximizing overall electrical performance of the system, reliability, and cost effectiveness. Cooling requirements and configurations were developed for each of the subsystems of RHEPP. Finite element models that combine fluid flow and heat transfer were used to screen design concepts. The analysis includes one, two, and three dimensional heat transfer using surface heat transfer coefficients and boundary layer models. Experiments were conducted to verify the models as well as to evaluate cooling channel fabrication materials and techniques in Metglas wound cores. 10 refs.

  7. CF6 jet engine performance deterioration results

    NASA Technical Reports Server (NTRS)

    Lewis, R. J.; Humerickhouse, C. E.; Paas, J. E.

    1978-01-01

    The use of the performance baseline from the flight planning manual as a reference to measure changes in cruise fuel flow rates was discussed. For the CF6-6D engine, the introduction of design changes for performance and durability reasons was seen to introduce an average increment relative to this baseline of 3.2% WFM increase at Nl, 2.5% Fn increase at Nl, 0.8% specific fuel consumption (SFC) increase at Fn, and 7 C EGT increase at Nl, while maintaining sufficient SFC margin of the delivered airplane. The effect of revenue service deterioration and performance restoration relative to the reference was shown to be an adder on top of these design effects. A schematic of typical CF6-6D performance through revenue service and airline maintenance is presented in terms of percent cruise SFC relative to an airline datum point (average level upon entering revenue service). The typical changes in SFC margin are shown for airline revenue service through for installations and refurbishments.

  8. Healing with animals in the Levant from the 10th to the 18th century.

    PubMed

    Lev, Efraim

    2006-02-21

    Animals and products derived from different organs of their bodies have constituted part of the inventory of medicinal substances used in various cultures since ancient times. The article reviews the history of healing with animals in the Levant (The Land of Israel and parts of present-day Syria, Lebanon, and Jordan, defined by the Muslims in the Middle Ages as Bilad al-Sham) in the medieval and early Ottoman periods. Intensive research into the phenomenon of zootherapy in the medieval and early Ottoman Levant has yielded forty-eight substances of animal origin that were used medicinally. The vast majority of these substances were local and relatively easy to obtain. Most of the substances were domestic (honey, wax, silkworm, etc.), others were part of the local wildlife (adder, cuttle fish, flycatcher, firefly, frog, triton, scorpion, etc.), part of the usual medieval household (milk, egg, cheese, lamb, etc.), or parasites (louse, mouse, stinkbug, etc.). Fewer substances were not local but exotic, and therefore rare and expensive (beaver testicles, musk oil, coral, ambergris, etc.). The range of symptoms that the substances of animal origin were used to treat was extensive and included most of the known diseases and maladies of that era: mainly hemorrhoids, burns, impotence, wounds, and skin, eye, and stomach diseases. Changes in the moral outlook of modern societies caused the use of several substances of animal origin to cease in the course of history. These include mummy, silkworm, stinkbug, scarabees, snail, scorpion, and triton.

  9. The adaptive significance of reptilian viviparity in the tropics: testing the maternal manipulation hypothesis.

    PubMed

    Webb, Jonathan K; Shine, Richard; Christian, Keith A

    2006-01-01

    Phylogenetic transitions from oviparity to viviparity in reptiles generally have occurred in cold climates, apparently driven by selective advantages accruing from maternal regulation of incubation temperature. But why, then, are viviparous reptiles so successful in tropical climates? Viviparity might enhance fitness in the tropics via the same pathway as in the temperate zone, if pregnant female reptiles in the tropics maintain more stable temperatures than are available in nests (Shine's maternal manipulation hypothesis). Alternatively, viviparity might succeed in the tropics for entirely different reasons than apply in the temperate zone. Our data support the maternal manipulation hypothesis. In a laboratory thermal gradient, pregnant death adders (Acanthophis praelongus) from tropical Australia maintained less variable body temperatures (but similar mean temperatures) than did nonpregnant females. Females kept at a diel range of 25-31 degrees C (as selected by pregnant females) gave birth earlier and produced larger offspring (greater body length and head size) than did females kept at 23-33 degrees C (as selected by nonpregnant snakes). Larger body size enhanced offspring recapture rates (presumably reflecting survival rates) in the field. Thus, even in the tropics, reproducing female reptiles manipulate the thermal regimes experienced by their developing embryos in ways that enhance the fitness of their offspring. This similarity across climatic zones suggests that a single general hypothesis--maternal manipulation of thermal conditions for embryogenesis--may explain the selective advantage of viviparity in tropical as well as cold-climate reptiles.

  10. Public health aspects of snakebite care in West Africa: perspectives from Nigeria.

    PubMed

    Habib, Abdulrazaq G

    2013-01-01

    Snakebite envenoming is a major public health problem among rural communities of the Nigerian savanna. The saw-scaled or carpet viper (Echis ocellatus) and, to a lesser extent, the African cobras (Naja spp.) and puff adders (Bitis arietans) have proved to be the most important cause of mortality and morbidity. The main clinical features of E. ocellatus envenoming are systemic hemorrhage, incoagulable blood, shock, local swelling, bleeding and, occasionally, necrosis. Bites may be complicated by amputation, blindness, disability, disfigurement, mutilation, tissue destruction and psychological consequences. Antivenom remains the hallmark and mainstay of envenoming management while studies in Nigeria confirm its protection of over 80% against mortality from carpet-viper bites. However, the availability, distribution and utilization of antivenom remain challenging although two new antivenoms (monospecific EchiTab G and trispecific EchiTab ICP-Plus) derived from Nigerian snake venoms have proven very effective and safe in clinical trials. A hub-and-spoke strategy is suggested for broadening antivenom access to endemic rural areas together with instituting quality assurance, standardization and manpower training. With the advent of antivenomics, national health authorities must be aided in selecting and purchasing antivenoms appropriate to their national needs while manufacturers should be helped in practical ways to improve the safety, efficacy and potential coverage against snake venoms and pricing of their products. PMID:24134780

  11. Identification of cDNAs encoding viper venom hyaluronidases: cross-generic sequence conservation of full-length and unusually short variant transcripts.

    PubMed

    Harrison, Robert A; Ibison, Frances; Wilbraham, Davina; Wagstaff, Simon C

    2007-05-01

    The immobilisation of prey by snakes is most efficiently achieved by the rapid dissemination of venom from its site of injection into the blood stream. Hyaluronidase is a common component of snake venoms and has been termed the "venom spreading factor". In the absence of nucleotide or protein sequence data to confirm the functional identity of this venom component, we interrogated a venom gland EST database for the saw-scaled viper, Echis ocellatus (Nigeria), using the gene ontology (GO) term "carbohydrate metabolism". A single hyalurononglucosaminadase-activity matching sequence (EOC00242) was found and used to design PCR primers to acquire the full-length cDNA sequence. Although very different from the bee venom and mammalian hyaluronidase sequences, the E. ocellatus sequence retained all the catalytic, positional and structural residues that characterise this class of carbohydrate metabolising hydrolases. An extraordinarily high level of sequence identity (>95%) was observed in analogous venom gland cDNA sequences isolated (by PCR) from another saw-scaled viper species, E. pyramidum leakeyi (Kenya), and from the sahara horned viper, Cerastes cerastes cerastes (Egypt) and the puff adder, Bitis arietans (Nigeria). Smaller amplicons, lacking hyaluronidase catalytic residues because of 768 bp or 855 bp central deletions, appear to encode either truncated peptides without hyaluronidase activity, or are non-translated transcripts because they lack consensus translation initiating motifs. PMID:17210232

  12. An all solid state pulse power source for high PRF induction accelerators

    SciTech Connect

    Kirbie, H., LLNL

    1998-06-01

    Researchers at the Lawrence Livermore National Laboratory (LLNL) are developing a flexible, all solid-state pulsed power source that will enable an induction accelerator to produce mulitkiloampere electron beams at a maximum pulse repetition frequency (prf) of 2 MHz. The prototype source consists of three, 15-kV, 4.8-kA solid-state modulators stacked in an induction adder configuration. Each modulator contains over 1300 field-effect transistors (FETs) that quickly connect and disconnect four banks of energy storage capacitors to a magnetic induction core. The FETs are commanded on and off by an optical signal that determines the duration of the accelerating pulse. Further electronic circuitry is provided that resets the magnetic cores in each modulator immediately after the accelerating pulse. The system produces bursts of five or more pulses with an adjustable pulse width that ranges from 200 ns to 2 {micro}s The pulse duty factor within a burst can be as high as 25% while still allowing time for the induction core to reset. The solid-state modulator described above is called ARM-II and is named for the Advanced Radiographic Machine (ARM)-a powerful radiographic accelerator that will be the principal diagnostic device for the future Advanced Hydrotest Facility (AHF).

  13. Radiographic X-Ray Pulse Jitter

    SciTech Connect

    Mitton, C. V., Good, D. E., Henderson, D. J., Hogge, K. W.

    2011-01-15

    The Dual Beam Radiographic Facility consists of two identical radiographic sources. Major components of the machines are: Marx generator, water-filled pulse-forming line (PFL), water-filled coaxial transmission line, three-cell inductive voltage adder, and rod-pinch diode. The diode pulse has the following electrical specifications: 2.25-MV, 60-kA, 60-ns. Each source has the following x-ray parameters: 1-mm-diameter spot size, 4-rad at 1 m, 50-ns full width half max. The x-ray pulse is measured with PIN diode detectors. The sources were developed to produce high resolution images on single-shot, high-value experiments. For this application it is desirable to maintain a high level of reproducibility in source output. X-ray pulse jitter is a key metric for analysis of reproducibility. We will give measurements of x-ray jitter for each machine. It is expected that x-ray pulse jitter is predominantly due to PFL switch jitter, and therefore a correlation of the two will be discussed.

  14. A high-speed multiplexer-based fine-grain pipelined architecture for digital fuzzy logic controllers

    NASA Astrophysics Data System (ADS)

    Rashidi, Bahram; Masoud Sayedi, Sayed

    2015-12-01

    Design and implementation of a high-speed multiplexer-based fine-grain pipelined architecture for a general digital fuzzy logic controller has been presented. All the operators have been designed at gate level. For the multiplication, a multiplexer-based modified Wallace tree multiplier has been designed, and for the division and addition multiplexer-based non-restoring parallel divider and multiplexer-based Manchester adder have been used, respectively. To further increase the processing speed, fine-grain pipelining technique has been employed. By using this technique, the critical path of the circuit is broken into finer pieces. Based on the proposed architecture, and by using Quartus II 9.1, a sample two-input, one-output digital fuzzy logic controller with eight rules has been successfully synthesised and implemented on Stratix II field programmable gate array. Simulations were carried out using DSP Builder in the MATLAB/Simulink tool at a maximum clock rate of 301.84 MHz.

  15. A 6 kV arbitrary waveform generator for the Tevatron Electron Lens

    DOE PAGES

    Pfeffer, H.; Saewert, G.

    2011-11-09

    This paper reports on a 6 kV modulator built and installed at Fermilab to drive the electron gun anode for the Tevatron Electron Lens (TEL). The TEL was built with the intention of shifting the individual (anti)proton bunch tunes to even out the tune spread among all 36 bunches with the desire of improving Tevatron integrated luminosity. This modulator is essentially a 6 kV arbitrary waveform generator that enables the TEL to define the electron beam intensity on a bunch-by-bunch basis. A voltage waveform is constructed having a 7 μs duration that corresponds to the tune shift requirements of amore » 12-bunch (anti)proton beam pulse train. This waveform is played out for any one or all three bunch trains in the Tevatron. The programmed waveform voltages transition to different levels at time intervals corresponding to the 395 ns bunch spacing. In addition, complex voltage waveforms can be played out at a sustained rate of 143 kHz over the full 6 kV output range. This paper describes the novel design of the inductive adder topology employing five transformers. It describes the design aspects that minimize switching losses for this multi-kilovolt, high repetition rate and high duty factor application.« less

  16. Healing with animals in the Levant from the 10th to the 18th century

    PubMed Central

    Lev, Efraim

    2006-01-01

    Animals and products derived from different organs of their bodies have constituted part of the inventory of medicinal substances used in various cultures since ancient times. The article reviews the history of healing with animals in the Levant (The Land of Israel and parts of present-day Syria, Lebanon, and Jordan, defined by the Muslims in the Middle Ages as Bilad al-Sham) in the medieval and early Ottoman periods. Intensive research into the phenomenon of zootherapy in the medieval and early Ottoman Levant has yielded forty-eight substances of animal origin that were used medicinally. The vast majority of these substances were local and relatively easy to obtain. Most of the substances were domestic (honey, wax, silkworm, etc.), others were part of the local wildlife (adder, cuttle fish, flycatcher, firefly, frog, triton, scorpion, etc.), part of the usual medieval household (milk, egg, cheese, lamb, etc.), or parasites (louse, mouse, stinkbug, etc.). Fewer substances were not local but exotic, and therefore rare and expensive (beaver testicles, musk oil, coral, ambergris, etc.). The range of symptoms that the substances of animal origin were used to treat was extensive and included most of the known diseases and maladies of that era: mainly hemorrhoids, burns, impotence, wounds, and skin, eye, and stomach diseases. Changes in the moral outlook of modern societies caused the use of several substances of animal origin to cease in the course of history. These include mummy, silkworm, stinkbug, scarabees, snail, scorpion, and triton. PMID:16504024

  17. A Single Chip VLSI Implementation of a QPSK/SQPSK Demodulator for a VSAT Receiver Station

    NASA Technical Reports Server (NTRS)

    Kwatra, S. C.; King, Brent

    1995-01-01

    This thesis presents a VLSI implementation of a QPSK/SQPSK demodulator. It is designed to be employed in a VSAT earth station that utilizes the FDMA/TDM link. A single chip architecture is used to enable this chip to be easily employed in the VSAT system. This demodulator contains lowpass filters, integrate and dump units, unique word detectors, a timing recovery unit, a phase recovery unit and a down conversion unit. The design stages start with a functional representation of the system by using the C programming language. Then it progresses into a register based representation using the VHDL language. The layout components are designed based on these VHDL models and simulated. Component generators are developed for the adder, multiplier, read-only memory and serial access memory in order to shorten the design time. These sub-components are then block routed to form the main components of the system. The main components are block routed to form the final demodulator.

  18. Universal computing by DNA origami robots in a living animal

    PubMed Central

    Levner, Daniel; Ittah, Shmulik; Abu-Horowitz, Almogit; Bachelet, Ido

    2014-01-01

    Biological systems are collections of discrete molecular objects that move around and collide with each other. Cells carry out elaborate processes by precisely controlling these collisions, but developing artificial machines that can interface with and control such interactions remains a significant challenge. DNA is a natural substrate for computing and has been used to implement a diverse set of mathematical problems1-3, logic circuits4-6 and robotics7-9. The molecule also naturally interfaces with living systems, and different forms of DNA-based biocomputing have previously been demonstrated10-13. Here we show that DNA origami14-16 can be used to fabricate nanoscale robots that are capable of dynamically interacting with each other17-18 in a living animal. The interactions generate logical outputs, which are relayed to switch molecular payloads on or off. As a proof-of-principle, we use the system to create architectures that emulate various logic gates (AND, OR, XOR, NAND, NOT, CNOT, and a half adder). Following an ex vivo prototyping phase, we successfully employed the DNA origami robots in living cockroaches (Blaberus discoidalis) to control a molecule that targets the cells of the animal. PMID:24705510

  19. Nanoimprint system development and status for high-volume semiconductor manufacturing

    NASA Astrophysics Data System (ADS)

    Iwamoto, Kazunori; Iwanaga, Takehiko; Sreenivasan, S. V.; Iwasa, Junji

    2015-10-01

    Imprint lithography has been shown to be an effective technique for replication of nano-scale features. Jet and Flash Imprint Lithography* (J-FIL*) involves the field-by-field deposition and exposure of a low viscosity resist deposited by jetting technology onto the substrate. The patterned mask is lowered into the fluid which then quickly flows into the relief patterns in the mask by capillary action. Following this filling step, the resist is crosslinked under UV radiation, and then the mask is removed, leaving a patterned resist on the substrate. The purpose of this paper is to describe the technology advancements made to both wafer imprint and mask replication systems that will be applied for the fabrication of advanced devices such as NAND Flash memory and DRAM. Overlay of better than 5nm (mean + 3sigma) has been demonstrated, and throughputs of better than 10 wafers per imprint station are now routinely achieved. Defectivity has been reduced by more than two orders of magnitude and particle adders within the tool have come down by approximately four orders of magnitude. A pilot line tool, the FPA- 1100 NZ2, was used to generate most of the results in this work. Additionally, particle control in a mask replication tool is addressed, with the purpose of extending the

  20. Design of efficient circularly symmetric two-dimensional variable digital FIR filters.

    PubMed

    Bindima, Thayyil; Elias, Elizabeth

    2016-05-01

    Circularly symmetric two-dimensional (2D) finite impulse response (FIR) filters find extensive use in image and medical applications, especially for isotropic filtering. Moreover, the design and implementation of 2D digital filters with variable fractional delay and variable magnitude responses without redesigning the filter has become a crucial topic of interest due to its significance in low-cost applications. Recently the design using fixed word length coefficients has gained importance due to the replacement of multipliers by shifters and adders, which reduces the hardware complexity. Among the various approaches to 2D design, transforming a one-dimensional (1D) filter to 2D by transformation, is reported to be an efficient technique. In this paper, 1D variable digital filters (VDFs) with tunable cut-off frequencies are designed using Farrow structure based interpolation approach, and the sub-filter coefficients in the Farrow structure are made multiplier-less using canonic signed digit (CSD) representation. The resulting performance degradation in the filters is overcome by using artificial bee colony (ABC) optimization. Finally, the optimized 1D VDFs are mapped to 2D using generalized McClellan transformation resulting in low complexity, circularly symmetric 2D VDFs with real-time tunability. PMID:27222739

  1. Highly Uniform Carbon Nanotube Field-Effect Transistors and Medium Scale Integrated Circuits.

    PubMed

    Chen, Bingyan; Zhang, Panpan; Ding, Li; Han, Jie; Qiu, Song; Li, Qingwen; Zhang, Zhiyong; Peng, Lian-Mao

    2016-08-10

    Top-gated p-type field-effect transistors (FETs) have been fabricated in batch based on carbon nanotube (CNT) network thin films prepared from CNT solution and present high yield and highly uniform performance with small threshold voltage distribution with standard deviation of 34 mV. According to the property of FETs, various logical and arithmetical gates, shifters, and d-latch circuits were designed and demonstrated with rail-to-rail output. In particular, a 4-bit adder consisting of 140 p-type CNT FETs was demonstrated with higher packing density and lower supply voltage than other published integrated circuits based on CNT films, which indicates that CNT based integrated circuits can reach to medium scale. In addition, a 2-bit multiplier has been realized for the first time. Benefitted from the high uniformity and suitable threshold voltage of CNT FETs, all of the fabricated circuits based on CNT FETs can be driven by a single voltage as small as 2 V. PMID:27459084

  2. Large area formation of self-aligned crystalline domains of organic semiconductors on transistor channels using CONNECT (Presentation Recording)

    NASA Astrophysics Data System (ADS)

    Park, Steve

    2015-09-01

    The electronic properties of solution-processable small molecule organic semiconductors (OSCs) have rapidly improved in recent years, rendering them highly promising for various low-cost large area electronic applications such as active matrix displays, radio frequency identification tags, and integrated logic circuits. However, practical applications of organic electronics requires patterned and precisely registered OSC film within the transistor channel region with uniform electrical properties over a large area, a task that remains a significant challenge. Here we present a novel technique known as CONNECT (Controlled OSC NucleatioN and Extension for CircuiTs), which utilizes differential surface energy and solution shearing to simultaneously generate self-patterned and self-registered OSC film within the channel region and with aligned crystalline domains, resulting in low device-to-device variability. We have fabricated transistor density as high as 840 dpi, with a yield of 99%. We have successfully built various logic gates and a 2-bit half adder circuit, demonstrating the practical applicability of our technique for large-scale circuit fabrication. CONNECT was expanded to use with inkjet printed silver electrodes, showing the versatility of our method to accommodate various solution deposition and fabrication methods.

  3. Decreased snake venom metalloproteinase effects via inhibition of enzyme and modification of fibrinogen.

    PubMed

    Nielsen, Vance G; Cerruti, Marc A; Valencia, Olivia M; Amos, Quinlan

    2016-10-01

    Since the introduction of antivenom administration 120 years ago to treat venomous snake bit, it has been the gold standard for saving life and limb. However, this therapeutic approach is not always effective and not without potential life-threatening side effects. We tested a new paradigm to abrogate the plasmatic anticoagulant effects of fibrinogenolytic snake venom metalloproteinases by modification of fibrinogen with iron and carbon monoxide and by inhibiting these Zn(2+) dependent metalloproteinases directly with carbon monoxide exposure. Assessment of the fibrinogenolytic effects of venoms collected from Puff adder, Gaboon viper and Indian cobra snakes on plasmatic coagulation kinetics was performed with thrombelastography. Pretreatment of plasma with iron and carbon monoxide exposure markedly attenuated the effects of all three venoms, and direct pretreatment of each venom with carbon monoxide also significantly decreased the ability to compromise coagulation. These results demonstrated that the introduction of a transition metal (e.g., modulation of the α-chain of fibrinogen with iron), modulation of transition metal in heme (e.g., carbon monoxide modulation of fibrinogen-bound heme iron), and direct inhibition of transition metal containing venom enzymes (e.g., CO binding to Zn(2+) or displacing Zn(2+) from the catalytic site) significantly decreased fibrinogenolytic activity. This biometal modulation strategy to attenuate the anticoagulant effects of snake venom metalloproteinases could potentially diminish hemostatic injury in envenomed patients until antivenom can be administered. PMID:27492573

  4. Star sensing for an earth imaging sensor

    NASA Technical Reports Server (NTRS)

    Ellis, Kenneth K. (Inventor); Griffith, Paul C. (Inventor)

    2012-01-01

    A star sensor includes (a) a scan mirror for scanning at least one star; (b) a detector array, coupled to the scan mirror, for detecting the one star; and (c) a processor, coupled to the detector array. The processor includes a first filter configured to reduce noise spikes in the detected one star, and provide a detection mask of filtered data. Also included is a second filter configured to reduce non-contiguous samples in the detection mask. A centroid calculator is included to determine a location of the one star, after the first and second filtering. The first filter includes a median filter, followed by an averaging filter, both configured to filter the one star in an along-scan direction of the scan mirror. The first filter includes another median filter, which is configured to filter the detected one star in the cross-scan direction of the scan mirror. An adder is included to subtract (a) output data from the other median filter from (b) output data from the averaging filter and provide filtered star data to the second filter.

  5. Cygnus Diverter Switch Analysis

    SciTech Connect

    G. Corrow, M. Hansen, D. Henderson, C. Mitton et al.

    2008-02-01

    The Cygnus Dual Beam Radiographic Facility consists of two 2.25-MV, 60-kA, 50-ns x-ray sources fielded in an underground laboratory at the Nevada Test Site. The tests performed in this laboratory involve study of the dynamic properties of plutonium and are called subcritical experiments. From end-to-end, the Cygnus machines utilize the following components: Marx generator, water-filled pulse-forming line (PFL), waterfilled coaxial transmission line (WTL), 3-cell inductive voltage adder (IVA), and rod-pinch diode. The upstream WTL interface to the PFL is via a radial insulator with coaxial geometry. The downstream WTL terminates in a manifold where the center conductor splits into three lines which individually connect to each of the IVA cell inputs. There is an impedance mismatch at this juncture. It is a concern that a reflected pulse due to anomalous behavior in the IVA or diode might initiate breakdown upon arrival at the upstream PFL/WTL insulator. Therefore near the beginning of the WTL a radial diverter switch is installed to protect the insulator from over voltage and breakdown. The diverter has adjustable gap spacing, and an in-line aqueous-solution (sodium thiosulfate) resistor array for energy dissipation. There are capacitive voltage probes at both ends of the WTL and on the diverter switch. These voltage signals will be analyzed to determine diverter performance. Using this analysis the usefulness of the diverter switch will be evaluated.

  6. Ring Counter Based ATPG for Low Transition Test Pattern Generation

    PubMed Central

    Begam, V. M. Thoulath; Baulkani, S.

    2015-01-01

    In test mode test patterns are applied in random fashion to the circuit under circuit. This increases switching transition between the consecutive test patterns and thereby increases dynamic power dissipation. The proposed ring counter based ATPG reduces vertical switching transitions by inserting test vectors only between the less correlative test patterns. This paper presents the RC-ATPG with an external circuit. The external circuit consists of XOR gates, full adders, and multiplexers. First the total number of transitions between the consecutive test patterns is determined. If it is more, then the external circuit generates and inserts test vectors in between the two test patterns. Test vector insertion increases the correlation between the test patterns and reduces dynamic power dissipation. The results prove that the test patterns generated by the proposed ATPG have fewer transitions than the conventional ATPG. Experimental results based on ISCAS'85 and ISCAS'89 benchmark circuits show 38.5% reduction in the average power and 50% reduction in the peak power attained during testing with a small size decoding logic. PMID:26075295

  7. Research on pinching characteristics of electron beams emitted from different cathode surfaces of a rod-pinch diode

    NASA Astrophysics Data System (ADS)

    Gao, Yi; Qiu, Aici; Zhang, Zhong; Zhang, Pengfei; Wang, Zhiguo; Yang, Hailiang

    2010-07-01

    The particle-in-cell code UNIPIC is used to simulate the working process of a rod-pinch diode and investigate the pinching characteristics of electron beams emitted from different cathode surfaces. The simulation results indicate that the electron beam emitted from the upstream surface pinches better than from other surfaces when all the three surfaces emit electrons. The charge-density deposition on the anode surface peaks at the rod tip while the deposited charge density is approximately uniform over the first 15 mm of the rod before rapidly increasing over the last 3 mm, indicating a large axial extent of electron deposition. For the case of single-surface emission, the pinching quality of the electron beam emitted from the downstream surface is better than those from other surfaces. The charge-density deposition peaks at the rod tip and decreases rapidly off the tip. Based on the relationship of Larmor radius, beam's self-magnetic field, and the spatial current distribution, the above simulation results are analyzed theoretically. The experiments are performed on the inductive voltage adder to examine the simulations. By comparing the axial distribution of the radiation on the anode rod measured with the pinhole camera and the on-axis forward x-ray dose measured with the LiF thermoluminescent detectors, the simulation results are verified. The electron emission suppression method and the impedance change for each case are investigated or discussed in this paper.

  8. Genetic adaptive system for image understanding and learning research. Phase 1. Final technical report, 1 February-1 August 1989

    SciTech Connect

    Douthat, D.Z.; Ross, K.W.

    1989-08-01

    This report documents the efforts and results of initial phase research on machine learning directed at application for real-time machine vision and automatic target recognition. The particular paradigm pursued is based on genetic algorithms and classifiers modeled on the summation of Mendelian genetic recombination, Darwinian selection, and ecological notions of competition. This machine-learning approach is strongly supported by sound statistical theory. A second thread of research was the development of massively parallel computing hardware based on the Geometric/Arithmetic Parallel Processor (GAPP). This machine has a large number of processors, each one bit wide with a full Arithmetic/Logic Unit (full adder) and with local memory per processor. The basic research hypothesis of the subject effort has been that GAPP contained sufficient hardware capability to provide a substrate for a Classifier and Genetic Algorithm system. The goal has been demonstrated by constructing and running the necessary software on the GAPP, its controller and its host. The resulting fusion of software and hardware is called a Genetic Algorithm/Classifier Engine (GACE) in the same sense as a LISP engine or a data base engine. The resulting quantum jump in performance should open doors both to application and to more interesting and relevant research.

  9. FAST TRACK COMMUNICATION: Reversible arithmetic logic unit for quantum arithmetic

    NASA Astrophysics Data System (ADS)

    Kirkedal Thomsen, Michael; Glück, Robert; Axelsen, Holger Bock

    2010-09-01

    This communication presents the complete design of a reversible arithmetic logic unit (ALU) that can be part of a programmable reversible computing device such as a quantum computer. The presented ALU is garbage free and uses reversible updates to combine the standard reversible arithmetic and logical operations in one unit. Combined with a suitable control unit, the ALU permits the construction of an r-Turing complete computing device. The garbage-free ALU developed in this communication requires only 6n elementary reversible gates for five basic arithmetic-logical operations on two n-bit operands and does not use ancillae. This remarkable low resource consumption was achieved by generalizing the V-shape design first introduced for quantum ripple-carry adders and nesting multiple V-shapes in a novel integrated design. This communication shows that the realization of an efficient reversible ALU for a programmable computing device is possible and that the V-shape design is a very versatile approach to the design of quantum networks.

  10. Modeling magnetically insulated devices using flow impedance

    SciTech Connect

    Mendel, C.W. Jr.; Rosenthal, S.E. )

    1995-04-01

    In modern pulsed power systems the electric field stresses at metal surfaces in vacuum transmission lines are so high that negative surfaces are space-charge-limited electron emitters. These electrons do not cause unacceptable losses because magnetic fields due to system currents result in net motion parallel to the electrodes. It has been known for several years that a parameter known as flow impedance is useful for describing these flows. Flow impedance is a measure of the separation between the anode and the mean position of the electron cloud, and it will be shown in this paper that in many situations flow impedance depends upon the geometry of the transmission line upstream of the point of interest. It can be remarkably independent of other considerations such as line currents and voltage. For this reason flow impedance is a valuable design parameter. Models of impedance transitions and voltage adders using flow impedance will be developed. Results of these models will be compared to two-dimensional, time-dependent, particle-in-cell simulations.

  11. Hardware Implementation of a Bilateral Subtraction Filter

    NASA Technical Reports Server (NTRS)

    Huertas, Andres; Watson, Robert; Villalpando, Carlos; Goldberg, Steven

    2009-01-01

    A bilateral subtraction filter has been implemented as a hardware module in the form of a field-programmable gate array (FPGA). In general, a bilateral subtraction filter is a key subsystem of a high-quality stereoscopic machine vision system that utilizes images that are large and/or dense. Bilateral subtraction filters have been implemented in software on general-purpose computers, but the processing speeds attainable in this way even on computers containing the fastest processors are insufficient for real-time applications. The present FPGA bilateral subtraction filter is intended to accelerate processing to real-time speed and to be a prototype of a link in a stereoscopic-machine- vision processing chain, now under development, that would process large and/or dense images in real time and would be implemented in an FPGA. In terms that are necessarily oversimplified for the sake of brevity, a bilateral subtraction filter is a smoothing, edge-preserving filter for suppressing low-frequency noise. The filter operation amounts to replacing the value for each pixel with a weighted average of the values of that pixel and the neighboring pixels in a predefined neighborhood or window (e.g., a 9 9 window). The filter weights depend partly on pixel values and partly on the window size. The present FPGA implementation of a bilateral subtraction filter utilizes a 9 9 window. This implementation was designed to take advantage of the ability to do many of the component computations in parallel pipelines to enable processing of image data at the rate at which they are generated. The filter can be considered to be divided into the following parts (see figure): a) An image pixel pipeline with a 9 9- pixel window generator, b) An array of processing elements; c) An adder tree; d) A smoothing-and-delaying unit; and e) A subtraction unit. After each 9 9 window is created, the affected pixel data are fed to the processing elements. Each processing element is fed the pixel value for

  12. Fundamentals and applications of dry CO2 cryogenic aerosol for photomask cleaning

    NASA Astrophysics Data System (ADS)

    Varghese, Ivin; Balooch, Mehdi; Bowers, Charles W.

    2010-09-01

    There is a dire need for the removal of all printable defects on lithography masks. As the technology node advances, smaller particles need to be efficiently removed from smaller features without any damage or adders. CO2 cryogenic aerosol cleaning is a dry, residue-free and chemically inert technique that doesn't suffer from disadvantages of conventional wet cleaning methods such as transmission/reflectivity loss, phase change, CD change, haze/progressive defects, and/or limitation on number of cleaning cycles. Ultra-pure liquid CO2 when dispensed through an optimally designed nozzle results in CO2 clusters that impart the required momentum for defect removal. Historically nanomachining debris removal has been established with this technique. Several improvements have been incorporated for cleaning of advanced node masks, which has enabled Full Mask Final Clean, a new capability that has been successfully demonstrated. The properties of the CO2 clusters can be captured utilizing the Phase Doppler Anemometry (PDA) and effect of varying process and design parameters can be verified. New nozzles have been designed to widen the cleaning process window for advanced node optical masks, without any damage to the weak primary features and/or sub-resolution assist features (SRAFs). This capability has been experimentally proven for high aspect ratio SRAFs e.g. 2.79 (52nm wide by 145 nm tall) as well as SRAFs 45nm wide by 73 nm tall. In this paper, 100% removal of soft defects that would have printed on advanced node masks is demonstrated. No printed defects larger than 50nm is observed after the CO2 cleaning. Stability of the cleaning and handling mechanisms has been demonstrated over the last 4.5 months in a production environment. The CO2 cleaning technique is expected to be effective for more advanced masks and Extreme Ultra-Violet (EUV) lithography.

  13. Hybridizing triboelectrification and electromagnetic induction effects for high-efficient mechanical energy harvesting.

    PubMed

    Hu, Youfan; Yang, Jin; Niu, Simiao; Wu, Wenzhuo; Wang, Zhong Lin

    2014-07-22

    The recently introduced triboelectric nanogenerator (TENG) and the traditional electromagnetic induction generator (EMIG) are coherently integrated in one structure for energy harvesting and vibration sensing/isolation. The suspended structure is based on two oppositely oriented magnets that are enclosed by hollow cubes surrounded with coils, which oscillates in response to external disturbance and harvests mechanical energy simultaneously from triboelectrification and electromagnetic induction. It extends the previous definition of hybrid cell to harvest the same type of energy with multiple approaches. Both the sliding-mode TENG and contact-mode TENG can be achieved in the same structure. In order to make the TENG and EMIG work together, transformers are used to match the output impedance between these two power sources with very different characteristics. The maximum output power of 7.7 and 1.9 mW on the same load of 5 kΩ was obtained for the TENG and EMIG, respectively, after impedance matching. Benefiting from the rational design, the output signal from the TENG and the EMIG are in phase. They can be added up directly to get an output voltage of 4.6 V and an output current of 2.2 mA in parallel connection. A power management circuit was connected to the hybrid cell, and a regulated voltage of 3.3 V with constant current was achieved. For the first time, a logic operation was carried out on a half-adder circuit by using the hybrid cell working as both the power source and the input digit signals. We also demonstrated that the hybrid cell can serve as a vibration isolator. Further applications as vibration dampers, triggers, and sensors are all promising.

  14. MOSFET-like CNFET based logic gate library for low-power application: a comparative study

    NASA Astrophysics Data System (ADS)

    Gowri Sankar, P. A.; Udhayakumar, K.

    2014-07-01

    The next generation of logic gate devices are expected to depend upon radically new technologies mainly due to the increasing difficulties and limitations of existing CMOS technology. MOSFET like CNFETs should ideally be the best devices to work with for high-performance VLSI. This paper presents results of a comprehensive comparative study of MOSFET-like carbon nanotube field effect transistors (CNFETs) technology based logic gate library for high-speed, low-power operation than conventional bulk CMOS libraries. It focuses on comparing four promising logic families namely: complementary-CMOS (C-CMOS), transmission gate (TG), complementary pass logic (CPL) and Domino logic (DL) styles are presented. Based on these logic styles, the proposed library of static and dynamic NAND-NOR logic gates, XOR, multiplexer and full adder functions are implemented efficiently and carefully analyzed with a test bench to measure propagation delay and power dissipation as a function of supply voltage. This analysis provides the right choice of logic style for low-power, high-speed applications. Proposed logic gates libraries are simulated using Synopsys HSPICE based on the standard 32 nm CNFET model. The simulation results demonstrate that, it is best to use C-CMOS logic style gates that are implemented in CNFET technology which are superior in performance compared to other logic styles, because of their low average power-delay-product (PDP). The analysis also demonstrates how the optimum supply voltage varies with logic styles in ultra-low power systems. The robustness of the proposed logic gate library is also compared with conventional and state-art of CMOS logic gate libraries.

  15. Robustness of the quantum Fourier transform with respect to static gate defects

    NASA Astrophysics Data System (ADS)

    Nam, Y. S.; Blümel, R.

    2014-04-01

    The quantum Fourier transform (QFT) is one of the most widely used quantum algorithms, ranging from its primary role in finding the periodicity hidden in a quantum state to its use in constructing a quantum adder. Testing how the QFT performs under more realistic conditions, we find that the QFT, when used for period finding, shows extraordinary robustness with respect to static gate defects. For instance, replacing all rotation angles π /2j of the controlled rotation gates in the QFT circuit by π(1+r )/2j, where r is a uniformly distributed random variable taking values in the range [-1,1], effectively resulting in a QFT with random gates, the QFT performs well above the expected random result. However, it is important to keep the 2j terms in the denominators of the rotation angles, resulting in random, but hierarchically random, gates. Relaxing this hierarchical structure of the QFT circuit, we find that the performance of the QFT deteriorates significantly. This observation indicates that the hierarchical structure of the quantum circuit of the QFT is more important for the observed robustness in performance than the precise actions of individual gates. In addition to the specific example of the QFT circuit studied here, this observation also corroborates our experience with more general and more complex quantum circuits. Thus, backed by our detailed numerical and analytical results, we may condense the results of our research into the following general principle: The topology of a quantum circuit is more important than the precise actions of its gates.

  16. A methodology for the characterization of arithmetic circuits on CMOS deep submicron technologies

    NASA Astrophysics Data System (ADS)

    Estrada, Adrian; Jimenez, Carlos J.; Valencia, Manuel

    2005-06-01

    Integration technologies have favored the design and implementation of more complex circuits. Thanks to this increased complexity, these circuits are capable of implementing algorithms which a few years ago were too expensive in both area and computational resources. However, they now offer interesting choices which should be considered. This new generation of integrated circuits nevertheless presents other kinds of restrictions that the designer should bear in mind. Parameters such as frequency of operation or power consumption are new restrictions that the designer has to deal with in order to fulfill the conditions established by the circuit functionality. Finally, the shrinking integration scale of current technologies makes the timing behavior of the design differ from previous technologies. Thus, a review of the timing behavior of the digital circuit should be done. So far, arithmetic circuits have been used as a benchmark for the analysis and design procedures of digital circuits. Therefore, it is our goal now to analyze both conventional and modern arithmetic circuits structures for different deep-submicron technologies. To achieve this goal, a good solution is to characterize a set of algorithmic circuits for several deep submicron processes, so that the designer can select the most suitable one depending upon the intended application and existing restrictions. In this paper, the first steps to attain such selection are presented. In particular, we propose a design and VHDL characterization methodology based on an RTL description of each component, on the utilization of an automated synthesis tool, and on the generation of logic characteristics from the logic level. This methodology is applied to a set of adders structures, the results of which are also presented.

  17. Recovery of soil physical properties and microbiology in foresty drained peatlands from the impact of forest machinery

    NASA Astrophysics Data System (ADS)

    Lepilin, Dmitrii; Kimura, Bryn; Uusitalo, Jori; Laiho, Raija; Fritze, Hannu; Lauren, Ari; Tuittila, Eeva-Stiina

    2016-04-01

    Forestry-drained peatlands occupy approximately 5.7 million ha and represent almost one fourth of the total forest surface in Finland. They are subjected to the same silvicultural harvesting operations as upland forests. However, although the potential of timber harvesting to cause detrimental effects on soil is well documented in upland forests, the knowledge on environmental impact of harvesting machinery on peat soils is still lacking. To assess the impact of harvesting machines on peat physical properties and biology we collected soil samples from six peatland forests that were harvested by commonly employed Harvester and Forwarder. Samples were taken from trails formed by harvesting machinery (treatment plots) and outside of trails (control plots unaffected by machinery traffic) to a depth of 15 cm. To adders the recovery of soil properties after disturbance we sampled sites that form a chronosequence in respect to time since harvesting: 1 month (class I), 3-4 years (class II) and 14-15 years (class III). The physical and microbiological properties of soil samples were analyzed in laboratory. Harvesting operations with heavy machinery appeared to significantly increase the bulk density of peat in the machines' trails at recently harvested sites in comparison to control plots. Following change in bulk density there was change of pore size distribution with decreasing macrospores quantity. This led to slight decrease of total porosity and decrease of air filled porosity. Water retention capacity increased with increasing bulk density. CO2 evolution increased in the trails of class I site with where dissolved organic carbon concurrently decreased. While there was not impact of harvesting on microbial biomass or carbon, PLFA analysis indicated that machinery traffic caused a shift in microbial community structure. Results of class II and class III sites showed a recovery of physical properties within 16 years: treatment plots and control plots started to resemble

  18. Use of a radial self-field diode geometry for intense pulsed ion beam generation at 6 MeV on Hermes III

    SciTech Connect

    Renk, T. J. Harper-Slaboszewicz, V.; Mikkelson, K. A.; Ginn, W. C.; Ottinger, P. F.; Schumer, J. W.

    2014-12-15

    We investigate the generation of intense pulsed focused ion beams at the 6 MeV level using an inductive voltage adder (IVA) pulsed-power generator, which employs a magnetically insulated transmission line (MITL). Such IVA machines typical run at an impedance of few tens of Ohms. Previous successful intense ion beam generation experiments have often featured an “axial” pinch-reflex ion diode (i.e., with an axial anode-cathode gap) and operated on a conventional Marx generator/water line driver with an impedance of a few Ohms and no need for an MITL. The goals of these experiments are to develop a pinch-reflex ion diode geometry that has an impedance to efficiently match to an IVA, produces a reasonably high ion current fraction, captures the vacuum electron current flowing forward in the MITL, and focuses the resulting ion beam to small spot size. A new “radial” pinch-reflex ion diode (i.e., with a radial anode-cathode gap) is found to best demonstrate these properties. Operation in both positive and negative polarities was undertaken, although the negative polarity experiments are emphasized. Particle-in-cell (PIC) simulations are consistent with experimental results indicating that, for diode impedances less than the self-limited impedance of the MITL, almost all of the forward-going IVA vacuum electron flow current is incorporated into the diode current. PIC results also provide understanding of the diode-impedance and ion-focusing properties of the diode. In addition, a substantial high-energy ion population is also identified propagating in the “reverse” direction, i.e., from the back side of the anode foil in the electron beam dump.

  19. An example of a digital synthesis approach to DSP design: The AGS transverse damper

    SciTech Connect

    Brown, K.A.; Smith, G.; Wong, V.

    1997-07-01

    Using Verilog HDL and Synopsys, the digital signal processing of the AGS Transverse Damper was designed and fitted to an Altera Flex l0k FPGA. Using a control point specification style in the high level description greatly simplified the design by placing the burden of specifying the controller on the digital synthesizer. The basic design and low level simulation are presented as well as the design methodology. The purpose of the AGS Transverse Damper is to control instabilities and injection errors that may arise in high intensity proton beams being accelerated in the AGS. The system block diagram for the DSP is shown in Figure 1. The inputs to the system come from a normalization unit. This normalization unit takes two signals as input, a sum of beam position signal plates, and a difference from the plates. The output of the normalization unit is the difference divided by the sum. This Quotient is sent to the first ALU (as Qin[11..0]). Taking differences between position measurements the system acts as a notch filter. The Second ALU computes a running sum of the output of the first ALU. This then acts to remove any offsets in the Quotient (and thus this part acts as a high pass filter - removing any baseline components to the signal). The depth of the first FIFO (between adder and subtract units) basically determines the low pass behaviour. The multiplier serves the purpose of overall loop gain for the system (the complete system is a real-time feedback system). The FIFO on the output is used to provide the correct amount of delay for the system.

  20. Compact implementation of dynamic receive apodization in ultrasound scanners

    NASA Astrophysics Data System (ADS)

    Tomov, Borislav G.; Jensen, Jørgen A.

    2004-04-01

    The image quality in medical ultrasound scanners is determined by several factors, one of which is the ability of the receive beamformer to change the aperture weighting function with depth and beam angle. In digital beamformers, precise dynamic apodization can be achieved by representing that function by numeric sequences. For a 15 cm scan depth and 100 lines per image, a 64-channel, 40 MHz ultrasound beamformer may need almost 50 million coefficients. A more coarse representation of the aperture relieves the memory requirements but does not enable compact and precise beamforming. Previously, the authors have developed a compact beamformer architecture which utilizes sigma-delta A/D conversion, recursive delay generation and sparse sample reconstruction using FIR filters. The channel weights were here fixed. In this paper, a compact implementation of dynamic receive apodization is presented. It allows precise weighting coefficient generation and utilizes a recursive algorithm which shares its starting parameters with the recursive delay generation logic. Thus, only a separate calculation block, consisting of 5 adders and 5 registers, is necessary. A VHDL implementation in a Xilinx XCV2000E-7 FPGA has been made for the whole receive beamformer for assessing the necessary hardware resources and the achievable performance for that platform. The code implements dynamic apodization with an expanding aperture for either linear or phased array imaging. A complete 32-channel beamformer can operate at 129.82 MHz and occupies 1.28 million gates. Simulated in Matlab, a 64-channel beamformer provides gray scale image with around 55 dB dynamic range. The beamformed data can also be used for flow estimation.

  1. Nanowire nanocomputer as a finite-state machine.

    PubMed

    Yao, Jun; Yan, Hao; Das, Shamik; Klemic, James F; Ellenbogen, James C; Lieber, Charles M

    2014-02-18

    Implementation of complex computer circuits assembled from the bottom up and integrated on the nanometer scale has long been a goal of electronics research. It requires a design and fabrication strategy that can address individual nanometer-scale electronic devices, while enabling large-scale assembly of those devices into highly organized, integrated computational circuits. We describe how such a strategy has led to the design, construction, and demonstration of a nanoelectronic finite-state machine. The system was fabricated using a design-oriented approach enabled by a deterministic, bottom-up assembly process that does not require individual nanowire registration. This methodology allowed construction of the nanoelectronic finite-state machine through modular design using a multitile architecture. Each tile/module consists of two interconnected crossbar nanowire arrays, with each cross-point consisting of a programmable nanowire transistor node. The nanoelectronic finite-state machine integrates 180 programmable nanowire transistor nodes in three tiles or six total crossbar arrays, and incorporates both sequential and arithmetic logic, with extensive intertile and intratile communication that exhibits rigorous input/output matching. Our system realizes the complete 2-bit logic flow and clocked control over state registration that are required for a finite-state machine or computer. The programmable multitile circuit was also reprogrammed to a functionally distinct 2-bit full adder with 32-set matched and complete logic output. These steps forward and the ability of our unique design-oriented deterministic methodology to yield more extensive multitile systems suggest that proposed general-purpose nanocomputers can be realized in the near future.

  2. The portable autonomous device on the basis straw-chambers for studying secondary space radiation in a soft x-ray range on board ISS

    NASA Astrophysics Data System (ADS)

    Bondarenko, Valery; Shurshakov, Vyacheslav; Bondarenko, Valentina; Markina, Irina

    The portable autonomous device for detection of soft x-ray radiation is described. Source of x-ray radiation is transition and brake radiations high-energy particles at passage through a material of a wall of the ISS and internal covering of the ship. A detecting elements of the device are gas proportional chambers of type straw in diameter 10 mm, length 140 mm. The wall chambers (cathode) is made from capton by thickness 70 microns. The anode of the chamber represents the gold-plated tungsten wire in diameter 30 microns. The general sensitive area of the detector is equal 110 cm2. Straw of the chambers (8 pieces) are connected consistently and are continuously blown by a gas mixture with a speed of 0,1 cm3/minute. The gas balloon in capacity of 200 cm3 under pressure 8 atm is used for flow. The device is capable to work long time in radiating fields. High radiating stability of the detector is reached by application of a radiation-steady material for manufacturing of chambers, constant gas flow during an irradiation and use of a clearing mixture on the basis of CF4. The electronic part of the device consists of the preamplifiers connected to chambers, the adder -splitter of analog signals, the spectrometer amplifier and amplitude - digitizer converter (АDC). From a splitter the signal acts on the discriminator for management ADC. Use of the discriminator allows to cut out registration of high-energy particles. The information is written on silicon disk.

  3. Use of a radial self-field diode geometry for intense pulsed ion beam generation at 6 MeV on Hermes III

    NASA Astrophysics Data System (ADS)

    Renk, T. J.; Harper-Slaboszewicz, V.; Mikkelson, K. A.; Ginn, W. C.; Ottinger, P. F.; Schumer, J. W.

    2014-12-01

    We investigate the generation of intense pulsed focused ion beams at the 6 MeV level using an inductive voltage adder (IVA) pulsed-power generator, which employs a magnetically insulated transmission line (MITL). Such IVA machines typical run at an impedance of few tens of Ohms. Previous successful intense ion beam generation experiments have often featured an "axial" pinch-reflex ion diode (i.e., with an axial anode-cathode gap) and operated on a conventional Marx generator/water line driver with an impedance of a few Ohms and no need for an MITL. The goals of these experiments are to develop a pinch-reflex ion diode geometry that has an impedance to efficiently match to an IVA, produces a reasonably high ion current fraction, captures the vacuum electron current flowing forward in the MITL, and focuses the resulting ion beam to small spot size. A new "radial" pinch-reflex ion diode (i.e., with a radial anode-cathode gap) is found to best demonstrate these properties. Operation in both positive and negative polarities was undertaken, although the negative polarity experiments are emphasized. Particle-in-cell (PIC) simulations are consistent with experimental results indicating that, for diode impedances less than the self-limited impedance of the MITL, almost all of the forward-going IVA vacuum electron flow current is incorporated into the diode current. PIC results also provide understanding of the diode-impedance and ion-focusing properties of the diode. In addition, a substantial high-energy ion population is also identified propagating in the "reverse" direction, i.e., from the back side of the anode foil in the electron beam dump.

  4. COBRA accelerator for Sandia ICF diode research at Cornell University

    SciTech Connect

    Smith, D.L.; Ingwersen, P.; Bennett, L.F.; Boyes, J.D.; Anderson, D.E.; Greenly, J.B.; Sudan, R.N.

    1995-05-01

    The new COBRA accelerator is being built in stages at the Laboratory of Plasma Studies in Cornell University where its applications will include extraction diode and ion beam research in support of the light ion inertial confinement fusion (ICF) program at Sandia National Laboratories. The 4- to 5-MV, 125- to 250-kA accelerator is based on a four-cavity inductive voltage adder (IVA) design. It is a combination of new ferromagnetically-isolated cavities and self magnetically insulated transmission line (MITL) hardware and components from existing Sandia and Cornell facilities: Marx generator capacitors, hardware, and power supply from the DEMON facility; water pulse forming lines (PFL) and gas switch from the Subsystem Test Facility (STF); a HERMES-III intermediate store capacitor (ISC); and a modified ion diode from Cornell`s LION. The present accelerator consists of a single modified cavity similar to those of the Sandia SABRE accelerator and will be used to establish an operating system for the first stage initial lower voltage testing. Four new cavities will be fabricated and delivered in the first half of FY96 to complete the COBRA accelerator. COBRA is unique in the sense that each cavity is driven by a single pulse forming line, and the IVA output polarity may be reversed by rotating the cavities 180{degrees} about their vertical axis. The site preparations, tank construction, and diode design and development are taking place at Cornell with growing enthusiasm as this machine becomes a reality. Preliminary results with the single cavity and short positive inner cylinder MITL configuration will soon be available.

  5. Framework for Integrating Science Data Processing Algorithms Into Process Control Systems

    NASA Technical Reports Server (NTRS)

    Mattmann, Chris A.; Crichton, Daniel J.; Chang, Albert Y.; Foster, Brian M.; Freeborn, Dana J.; Woollard, David M.; Ramirez, Paul M.

    2011-01-01

    A software framework called PCS Task Wrapper is responsible for standardizing the setup, process initiation, execution, and file management tasks surrounding the execution of science data algorithms, which are referred to by NASA as Product Generation Executives (PGEs). PGEs codify a scientific algorithm, some step in the overall scientific process involved in a mission science workflow. The PCS Task Wrapper provides a stable operating environment to the underlying PGE during its execution lifecycle. If the PGE requires a file, or metadata regarding the file, the PCS Task Wrapper is responsible for delivering that information to the PGE in a manner that meets its requirements. If the PGE requires knowledge of upstream or downstream PGEs in a sequence of executions, that information is also made available. Finally, if information regarding disk space, or node information such as CPU availability, etc., is required, the PCS Task Wrapper provides this information to the underlying PGE. After this information is collected, the PGE is executed, and its output Product file and Metadata generation is managed via the PCS Task Wrapper framework. The innovation is responsible for marshalling output Products and Metadata back to a PCS File Management component for use in downstream data processing and pedigree. In support of this, the PCS Task Wrapper leverages the PCS Crawler Framework to ingest (during pipeline processing) the output Product files and Metadata produced by the PGE. The architectural components of the PCS Task Wrapper framework include PGE Task Instance, PGE Config File Builder, Config File Property Adder, Science PGE Config File Writer, and PCS Met file Writer. This innovative framework is really the unifying bridge between the execution of a step in the overall processing pipeline, and the available PCS component services as well as the information that they collectively manage.

  6. Ultrafast all-optical arithmetic logic based on hydrogenated amorphous silicon microring resonators

    NASA Astrophysics Data System (ADS)

    Gostimirovic, Dusan; Ye, Winnie N.

    2016-03-01

    For decades, the semiconductor industry has been steadily shrinking transistor sizes to fit more performance into a single silicon-based integrated chip. This technology has become the driving force for advances in education, transportation, and health, among others. However, transistor sizes are quickly approaching their physical limits (channel lengths are now only a few silicon atoms in length), and Moore's law will likely soon be brought to a stand-still despite many unique attempts to keep it going (FinFETs, high-k dielectrics, etc.). This technology must then be pushed further by exploring (almost) entirely new methodologies. Given the explosive growth of optical-based long-haul telecommunications, we look to apply the use of high-speed optics as a substitute to the digital model; where slow, lossy, and noisy metal interconnections act as a major bottleneck to performance. We combine the (nonlinear) optical Kerr effect with a single add-drop microring resonator to perform the fundamental AND-XOR logical operations of a half adder, by all-optical means. This process is also applied to subtraction, higher-order addition, and the realization of an all-optical arithmetic logic unit (ALU). The rings use hydrogenated amorphous silicon as a material with superior nonlinear properties to crystalline silicon, while still maintaining CMOS-compatibility and the many benefits that come with it (low cost, ease of fabrication, etc.). Our method allows for multi-gigabit-per-second data rates while maintaining simplicity and spatial minimalism in design for high-capacity manufacturing potential.

  7. Use of a radial self-field diode geometry for intense pulsed ion beam generation at 6 MeV on Hermes III

    SciTech Connect

    Renk, Timothy Jerome; Harper-Slaboszewicz, Victor Jozef; Mikkelson, Kenneth A.; Ginn, W. C.; Ottinger, P. F.; Schumer, J. W.

    2014-12-15

    We investigate the generation of intense pulsed focused ion beams at the 6 MeV level using an inductive voltage adder (IVA) pulsed-power generator, which employs a magnetically insulated transmission line (MITL). Such IVA machines typical run at an impedance of few tens of Ohms. Previous successful intense ion beam generation experiments have often featured an “axial” pinch-reflex ion diode (i.e., with an axial anode-cathode gap) and operated on a conventional Marx generator/water line driver with an impedance of a few Ohms and no need for an MITL. The goals of these experiments are to develop a pinch-reflex ion diode geometry that has an impedance to efficiently match to an IVA, produces a reasonably high ion current fraction, captures the vacuum electron current flowing forward in the MITL, and focuses the resulting ion beam to small spot size. Furthermore, a new “radial” pinch-reflex ion diode (i.e., with a radial anode-cathode gap) is found to best demonstrate these properties. Operation in both positive and negative polarities was undertaken, although the negative polarity experiments are emphasized. Particle-in-cell (PIC) simulations are consistent with experimental results indicating that, for diode impedances less than the self-limited impedance of the MITL, almost all of the forward-going IVA vacuum electron flow current is incorporated into the diode current. PIC results also provide understanding of the diode-impedance and ion-focusing properties of the diode. Additionally, a substantial high-energy ion population is also identified propagating in the “reverse” direction, i.e., from the back side of the anode foil in the electron beam dump.

  8. NASA Tech Briefs, January 2003

    NASA Technical Reports Server (NTRS)

    2003-01-01

    Topics covered include: Optoelectronic Tool Adds Scale Marks to Photographic Images; Compact Interconnection Networks Based on Quantum Dots; Laterally Coupled Quantum-Dot Distributed-Feedback Lasers; Bit-Serial Adder Based on Quantum Dots; Stabilized Fiber-Optic Distribution of Reference Frequency; Delay/Doppler-Mapping GPS-Reflection Remote-Sensing System; Ladar System Identifies Obstacles Partly Hidden by Grass; Survivable Failure Data Recorders for Spacecraft; Fiber-Optic Ammonia Sensors; Silicon Membrane Mirrors with Electrostatic Shape Actuators; Nanoscale Hot-Wire Probes for Boundary-Layer Flows; Theodolite with CCD Camera for Safe Measurement of Laser-Beam Pointing; Efficient Coupling of Lasers to Telescopes with Obscuration; Aligning Three Off-Axis Mirrors with Help of a DOE; Calibrating Laser Gas Measurements by Use of Natural CO2; Laser Ranging Simulation Program; Micro-Ball-Lens Optical Switch Driven by SMA Actuator; Evaluation of Charge Storage and Decay in Spacecraft Insulators; Alkaline Capacitors Based on Nitride Nanoparticles; Low-EC-Content Electrolytes for Low-Temperature Li-Ion Cells; Software for a GPS-Reflection Remote-Sensing System; Software for Building Models of 3D Objects via the Internet; "Virtual Cockpit Window" for a Windowless Aerospacecraft; CLARAty Functional-Layer Software; Java Library for Input and Output of Image Data and Metadata; Software for Estimating Costs of Testing Rocket Engines; Energy-Absorbing, Lightweight Wheels; Viscoelastic Vibration Dampers for Turbomachine Blades; Soft Landing of Spacecraft on Energy-Absorbing Self-Deployable Cushions; Pneumatically Actuated Miniature Peristaltic Vacuum Pumps; Miniature Gas-Turbine Power Generator; Pressure-Sensor Assembly Technique; Wafer-Level Membrane-Transfer Process for Fabricating MEMS; A Reactive-Ion Etch for Patterning Piezoelectric Thin Film; Wavelet-Based Real-Time Diagnosis of Complex Systems; Quantum Search in Hilbert Space; Analytic Method for Computing Instrument

  9. Incorporating global warming risks in power sector planning: A case study of the New England region. Volume 1

    SciTech Connect

    Krause, F.; Busch, J.; Koomey, J.

    1992-11-01

    Growing international concern over the threat of global climate change has led to proposals to buy insurance against this threat by reducing emissions of carbon (short for carbon dioxide) and other greenhouse gases below current levels. Concern over these and other, non-climatic environmental effects of electricity generation has led a number of states to adopt or explore new mechanisms for incorporating environmental externalities in utility resource planning. For example, the New York and Massachusetts utility commissions have adopted monetized surcharges (or adders) to induce emission reductions of federally regulated air pollutants (notably, SO{sub 2}, NO{sub x}, and particulates) beyond federally mandated levels. These regulations also include preliminary estimates of the cost of reducing carbon emissions, for which no federal regulations exist at this time. Within New England, regulators and utilities have also held several workshops and meetings to discuss alternative methods of incorporating externalities as well as the feasibility of regional approaches. This study examines the potential for reduced carbon emissions in the New England power sector as well as the cost and rate impacts of two policy approaches: environmental externality surcharges and a target- based approach. We analyze the following questions: Does New England have sufficient low-carbon resources to achieve significant reductions (10% to 20% below current levels) in fossil carbon emissions in its utility sector? What reductions could be achieved at a maximum? What is the expected cost of carbon reductions as a function of the reduction goal? How would carbon reduction strategies affect electricity rates? How effective are environmental externality cost surcharges as an instrument in bringing about carbon reductions? To what extent could the minimization of total electricity costs alone result in carbon reductions relative to conventional resource plans?

  10. Allowance trading under the Clean Air Act: Who should regulate, and when?

    SciTech Connect

    Lock, R.

    1993-07-01

    The goal of this paper is to explore how compliance with the Clean Air Act Amendments of 1990 (CAAA), especially Title IV and emission trading under it, will affect the current relationship between state and federal regulation. It is difficult, with the limited experience we have had under Title IV, to be definitive about or to be a very strong advocate of too many policy positions. What may be most helpful at this point is to identify where the difficult issues in state/federal relations might arise; and then to explore ways in which tensions might be either avoided or resolved. One anticipated conclusion is that a traditional regulatory mindset could be very destructive if applied to this new area of oversight without due sensitivity to what Congress is trying to achieve in Title IV. That concern pervaded the early legislative debates; and it persists today. Title IV presents some unique challenges to state regulators and will require some creative solutions and fresh thinking if the goals of Congress are to be realized and the full benefits that allowance trading can offer are to be reaped by electricity consumers. In the ultimate analysis, Title IV amounts to a massive internalization of the external costs imposed on society by acid rain deposition. (This places in serious question the notion of additional externality {open_quotes}adders{close_quotes} for sulfur dioxide (SO{sub 2}) and nitrous oxide (NO{sub x}) at the state level for utility supply planning purposes.) The whole point of Title IV is to give those directly charged with compliance, namely power producers, the maximum flexibility to pursue least-cost compliance solutions. Perhaps the biggest single factor in how well they do this will be how state regulators respond to their compliance and allowance trading initiatives.

  11. EUV mask and wafer defectivity: strategy and evaluation for full die defect inspection

    NASA Astrophysics Data System (ADS)

    Bonam, Ravi; Tien, Hung-Yu; Chou, Acer; Meli, Luciana; Halle, Scott; Wu, Ivy; Huang, Xiaoxia; Lei, Chris; Kuan, Chiyan; Wang, Fei; Corliss, Daniel; Fang, Wei; Jau, Jack; Qi, Zhengqing John; Badger, Karen; Turley, Christina; Rankin, Jed

    2016-03-01

    Over the past few years numerous advancements in EUV Lithography have proven its feasibility of insertion into High Volume Manufacturing (HVM).1, 2 A lot of progress is made in the area of pellicle development but a commercially solution with related infrastructure is currently unavailable.3, 4 Due to current mask structure and unavailability of a pellicle, a comprehensive strategy to qualify (native defects) and monitor (adder defects) defectivity on mask and wafer is required for implementing EUV Lithography in High Volume Manufacturing. In this work, we assess multiple strategies for mask and wafer defect inspection including a two-fold solution to leverage resolution of e-beam inspection along with throughput of optical inspection are evaluated. Defect capture rates for inspections based on full-die, critical areas based on priority and hotspots based on design and prior inspection data are evaluated. Each strategy has merits and de-merits, particularly related to throughput, effective die coverage and computational overhead. A production ready EUV Exposure tool was utilized to perform exposures at the IBM EUV Center of Excellence in Albany, NY for EUV Lithography Development along with a fully automated line of EUV Mask Infrastructure tools. We will present strategies considered in this study and discuss respective results. The results from the study indicate very low transfer rate of defect detection events from optical mask inspection. They also suggest a hybrid strategy of utilizing both optical and e-beam inspection can provide a comprehensive defect detection which can be employed in High Volume Manufacturing.

  12. Nanoimprint system development and status for high-volume semiconductor manufacturing

    NASA Astrophysics Data System (ADS)

    Takashima, Tsuneo; Takabayashi, Yukio; Nishimura, Naosuke; Emoto, Keiji; Matsumoto, Takahiro; Hayashi, Tatsuya; Kimura, Atsushi; Choi, Jin; Schumaker, Philip

    2016-03-01

    Imprint lithography has been shown to be an effective technique for replication of nano-scale features. Jet and Flash* Imprint Lithography (J-FIL*) involves the field-by-field deposition and exposure of a low viscosity resist deposited by jetting technology onto the substrate. The patterned mask is lowered into the fluid which then quickly flows into the relief patterns in the mask by capillary action. Following this filling step, the resist is crosslinked under UV radiation, and then the mask is removed, leaving a patterned resist on the substrate. Criteria specific to any lithographic process for the semiconductor industry include overlay, throughput and defectivity. The purpose of this paper is to describe the technology advancements made overlay, throughput and defectivity and to introduce the FPA-1200NZ2C cluster system designed for high volume manufacturing of semiconductor devices. in the reduction of particle adders in an imprint tool and introduce the new mask replication tool that will enable the fabrication of replica masks with added residual image placement errors suitable for memory devices with half pitches smaller than 15nm. Overlay results better than 5nm 3sigma have been demonstrated. To further enhance overlay, wafer chucks with improved flatness have been implemented to reduce distortion at the wafer edge. To address higher order corrections, a two part solution is discussed. An array of piezo actuators can be applied to enable linear corrections. Additional reductions in distortion can then be addressed by the local heating of a wafer field. The NZ2C cluster platform for high volume manufacturing is also discussed. System development continues this year with a target for introduction later in 2016. The first application is likely to be NAND Flash memory, and eventual use for DRAM and logic devices as both overlay and defectivity improve.

  13. Reconfigurable Fault Tolerance for FPGAs

    NASA Technical Reports Server (NTRS)

    Shuler, Robert, Jr.

    2010-01-01

    The invention allows a field-programmable gate array (FPGA) or similar device to be efficiently reconfigured in whole or in part to provide higher capacity, non-redundant operation. The redundant device consists of functional units such as adders or multipliers, configuration memory for the functional units, a programmable routing method, configuration memory for the routing method, and various other features such as block RAM, I/O (random access memory, input/output) capability, dedicated carry logic, etc. The redundant device has three identical sets of functional units and routing resources and majority voters that correct errors. The configuration memory may or may not be redundant, depending on need. For example, SRAM-based FPGAs will need some type of radiation-tolerant configuration memory, or they will need triple-redundant configuration memory. Flash or anti-fuse devices will generally not need redundant configuration memory. Some means of loading and verifying the configuration memory is also required. These are all components of the pre-existing redundant FPGA. This innovation modifies the voter to accept a MODE input, which specifies whether ordinary voting is to occur, or if redundancy is to be split. Generally, additional routing resources will also be required to pass data between sections of the device created by splitting the redundancy. In redundancy mode, the voters produce an output corresponding to the two inputs that agree, in the usual fashion. In the split mode, the voters select just one input and convey this to the output, ignoring the other inputs. In a dual-redundant system (as opposed to triple-redundant), instead of a voter, there is some means to latch or gate a state update only when both inputs agree. In this case, the invention would require modification of the latch or gate so that it would operate normally in redundant mode, and would separately latch or gate the inputs in non-redundant mode.

  14. Surface confined assemblies and polymers for sensing and molecular logic

    NASA Astrophysics Data System (ADS)

    de Ruiter, Graham; Altman, Marc; Motiei, Leila; Lahav, Michal; van der Boom, Milko E.

    2013-05-01

    Since the development of molecule-based sensors and the introduction of molecules mimicking the behavior of the AND gate in solution by de Silva in 1993, molecular (Boolean) Logic and Computing (MBLC) has become increasingly popular. The molecular approach toward Boolean logic resulted in intriguing proofs of concepts in solution including logic gates, half-adders, multiplexers, and flip-flop logic circuits. Molecular assemblies can perform diverse logic tasks by reconfiguring their inputs. Our recent research activities focus on MBLC with electrochromic polymers and immobilized polypyridyl complexes on solid support. We have designed a series of coordination-based thin films that are formed linearly by stepwise wet-chemical deposition or by self-propagating molecular assembly. The electrochromic properties of these films can be used for (i) detecting various analytes in solution and in the air, (ii) MBLC, (iii) electron-transfer studies, and (iv) interlayers for efficient inverted bulk-heterojunction solar cells. Our concept toward MBLC with functionalized surfaces is applicable to electrochemical and chemical inputs coupled with optical readout. Using this approach, we demonstrated various logic architectures with redox-active functionalized surfaces. Electrochemically operated sequential logic systems (e.g., flip-flops), multi-valued logic, and multi-state memory have been designed, which can improve computational power without increasing spatial requirements. Applying multi-valued digits in data storage and information processing could exponentially increase memory capacity. Our approach is applicable to highly diverse electrochromic thin films that operate at practical voltages (< 1.5 V).

  15. Optimization of current waveform tailoring for magnetically driven isentropic compression experiments

    NASA Astrophysics Data System (ADS)

    Waisman, E. M.; Reisman, D. B.; Stoltzfus, B. S.; Stygar, W. A.; Cuneo, M. E.; Haill, T. A.; Davis, J.-P.; Brown, J. L.; Seagle, C. T.; Spielman, R. B.

    2016-06-01

    The Thor pulsed power generator is being developed at Sandia National Laboratories. The design consists of up to 288 decoupled and transit time isolated capacitor-switch units, called "bricks," that can be individually triggered to achieve a high degree of pulse tailoring for magnetically driven isentropic compression experiments (ICE) [D. B. Reisman et al., Phys. Rev. Spec. Top.-Accel. Beams 18, 090401 (2015)]. The connecting transmission lines are impedance matched to the bricks, allowing the capacitor energy to be efficiently delivered to an ICE strip-line load with peak pressures of over 100 GPa. Thor will drive experiments to explore equation of state, material strength, and phase transition properties of a wide variety of materials. We present an optimization process for producing tailored current pulses, a requirement for many material studies, on the Thor generator. This technique, which is unique to the novel "current-adder" architecture used by Thor, entirely avoids the iterative use of complex circuit models to converge to the desired electrical pulse. We begin with magnetohydrodynamic simulations for a given material to determine its time dependent pressure and thus the desired strip-line load current and voltage. Because the bricks are connected to a central power flow section through transit-time isolated coaxial cables of constant impedance, the brick forward-going pulses are independent of each other. We observe that the desired equivalent forward-going current driving the pulse must be equal to the sum of the individual brick forward-going currents. We find a set of optimal brick delay times by requiring that the L2 norm of the difference between the brick-sum current and the desired forward-going current be a minimum. We describe the optimization procedure for the Thor design and show results for various materials of interest.

  16. Treatment of snakebite in Australia: the current evidence base and questions requiring collaborative multicentre prospective studies.

    PubMed

    Currie, Bart J

    2006-12-01

    Despite the wealth of anecdotes and case reports there are fundamental questions of management of snakebite in Australia that remain unresolved or for which the current evidence is limited. The efficacy in the field, potential limitations and possibility of improvements in pressure immobilisation first aid need objective studies in humans. Optimal bandage sizes, stretch and pressure for different sized limbs need further evaluation, as does the use of pressure pads. Better definitions of specific clinical envenoming syndromes attributable to individual snake species are required, including elucidation of within-genus variations, similarities and differences. Venom studies suggest this is especially important for species within the brown snake (Pseudonaja) and death adder (Acanthophis) genera. Appropriate antivenom types, doses and dosing intervals for individual snake species should be more formally studied in patients. Especially important are confirmation of the need for higher doses of brown snake antivenom, while possibly limiting unnecessarily high doses, confirmation of the critical importance of early antivenom use to prevent pre-synaptic neurotoxicity in Taipan and tiger snake bites and ascertainment of whether larger doses of antivenom are unhelpful in Taipan bites after specified time delays. Confirmation of clinical efficacy and dosing recommendations for use of tiger snake (Notechis) antivenom in envenoming from Australian copperhead (Austrelaps spp.), broad headed (Hoplocephalus spp.) and rough-scaled snakes (Tropidechis carinatus) also require formal study in patients. Other examples of clinical relevance of cross-specificity of current and future monospecific antivenoms and whether there are geographical variations in antivenom responses within species will require elucidation. Prospective multicentre collaborative studies with predefined data collection and serial venom level assays are proposed as the way forward in Australia to help resolve

  17. Novel sequences encoding venom C-type lectins are conserved in phylogenetically and geographically distinct Echis and Bitis viper species.

    PubMed

    Harrison, R A; Oliver, J; Hasson, S S; Bharati, K; Theakston, R D G

    2003-10-01

    Envenoming by Echis saw scaled vipers and Bitis arietans puff adders is the leading cause of death and morbidity in Africa due to snake bite. Despite their medical importance, the composition and constituent functionality of venoms from these vipers remains poorly understood. Here, we report the cloning of cDNA sequences encoding seven clusters or isoforms of the haemostasis-disruptive C-type lectin (CTL) proteins from the venom glands of Echis ocellatus, E. pyramidum leakeyi, E. carinatus sochureki and B. arietans. All these CTL sequences encoded the cysteine scaffold that defines the carbohydrate-recognition domain of mammalian CTLs. All but one of the Echis and Bitis CTL sequences showed greater sequence similarity to the beta than alpha CTL subunits in venoms of related Asian and American vipers. Four of the new CTL clusters showed marked inter-cluster sequence conservation across all four viper species which were significantly different from that of previously published viper CTLs. The other three Echis and Bitis CTL clusters showed varying degrees of sequence similarity to published viper venom CTLs. Because viper venom CTLs exhibit a high degree of sequence similarity and yet exert profoundly different effects on the mammalian haemostatic system, no attempt was made to assign functionality to the new Echis and Bitis CTLs on the basis of sequence alone. The extraordinary level of inter-specific and inter-generic sequence conservation exhibited by the Echis and Bitis CTLs leads us to speculate that antibodies to representative molecules should neutralise the biological function of this important group of venom toxins in vipers that are distributed throughout Africa, the Middle East and the Indian subcontinent. PMID:14557069

  18. Cygnus Water Switch Jitter

    SciTech Connect

    Charles V. Mitton, George D. Corrow, Mark D. Hansen, David J. Henderson, et al.

    2008-03-01

    The Cygnus Dual Beam Radiographic Facility consists of two identical radiographic sources - Cygnus 1 and Cygnus 2. Each source has the following x-ray output: 1-mm diameter spot size, 4 rad at 1 m, 50-ns Full Width Half Max. The diode pulse has the following electrical specifications: 2.25 MV, 60 kA, 60 ns. This Radiographic Facility is located in an underground tunnel test area at the Nevada Test Site (NTS). The sources were developed to produce high-resolution images on subcritical tests which are performed at NTS. Subcritical tests are single-shot, high-value events. For this application, it is desirable to maintain a high level of reproducibility in source output. The major components of the Cygnus machines are: Marx generator, water-filled pulse–forming line (PFL), water-filled coaxial transmission line, three-cell inductive voltage adder, and rod-pinch diode. A primary source of fluctuation in Cygnus shot-to-shot performance is jitter in breakdown of the main PFL switch, which is a “self-break” switch. The PFL switch breakdown time determines the peak PFL charging voltage, which ultimately affects the diode pulse. Therefore, PFL switch jitter contributes to shot-to-shot variation in source endpoint energy and dose. In this paper we will present PFL switch jitter analysis for both Cygnus machines and give the correlation with diode performance. For this analysis the PFL switch on each machine was maintained at a single gap setting which has been used for the majority of shots at NTS. In addition to this analysis, PFL switch performance for different switch gap settings taken recently will be examined. Lastly, implications of source jitter for radiographic diagnosis of subcritical shots will be discussed.

  19. Use of a radial self-field diode geometry for intense pulsed ion beam generation at 6 MeV on Hermes III

    DOE PAGES

    Renk, Timothy Jerome; Harper-Slaboszewicz, Victor Jozef; Mikkelson, Kenneth A.; Ginn, W. C.; Ottinger, P. F.; Schumer, J. W.

    2014-12-15

    We investigate the generation of intense pulsed focused ion beams at the 6 MeV level using an inductive voltage adder (IVA) pulsed-power generator, which employs a magnetically insulated transmission line (MITL). Such IVA machines typical run at an impedance of few tens of Ohms. Previous successful intense ion beam generation experiments have often featured an “axial” pinch-reflex ion diode (i.e., with an axial anode-cathode gap) and operated on a conventional Marx generator/water line driver with an impedance of a few Ohms and no need for an MITL. The goals of these experiments are to develop a pinch-reflex ion diode geometrymore » that has an impedance to efficiently match to an IVA, produces a reasonably high ion current fraction, captures the vacuum electron current flowing forward in the MITL, and focuses the resulting ion beam to small spot size. Furthermore, a new “radial” pinch-reflex ion diode (i.e., with a radial anode-cathode gap) is found to best demonstrate these properties. Operation in both positive and negative polarities was undertaken, although the negative polarity experiments are emphasized. Particle-in-cell (PIC) simulations are consistent with experimental results indicating that, for diode impedances less than the self-limited impedance of the MITL, almost all of the forward-going IVA vacuum electron flow current is incorporated into the diode current. PIC results also provide understanding of the diode-impedance and ion-focusing properties of the diode. Additionally, a substantial high-energy ion population is also identified propagating in the “reverse” direction, i.e., from the back side of the anode foil in the electron beam dump.« less

  20. Concept study of high volume food irradiation with a pulsed power accelerator

    SciTech Connect

    Turman, B.N.; Prestwich, K.R.; Neau, E.L.; Johnson, D.L.; Kensek, R.P.

    1993-12-31

    A concept study was initiated to establish technical requirements and processing cost estimates for a high power, high volume x-radiation food processing facility using pulsed power technology. The design study was directed toward a central processing plant that would transport and process the food products in standard pallets of 1.1m {times} 1.2m {times} 1.2m dimensions. The 1.2m depth of penetration, and a dose uniformity requirement of a factor of 2 between the maximum and minimum dose, led to a decision to employ x-radiation, produced from a 5 MeV electron beam. The electron beam is produced from a large-area cathode and accelerated by a multi-module pulsed power accelerator. The beam power for this design is 500 kW. An example application is developed for illustration, based on produce disinfestation at maximum exposure level of l00 krad and minimum exposure of 50 krad. In order to achieve this ratio of maximum to minimum dose, the pallet is rotated through 3609 while being exposed. The estimated process rate is approximately 30 metric tons/hour. The accelerator design was developed by scaling from the present high average power beam experiments in the Repetitive High Energy Pulsed Power (RHEPP) program, which will deliver an output of 350 kW in a 2.5 MeV beam. The high voltage is achieved by using 250 kV pulses that are added together with inductively-isolated adder cavities. This technology will be described, and results from the RHEPP experiments will be compared with the design requirements for the high power food processor application. Processing issues, technology limits, dose calculations, and cost estimates will be discussed.

  1. Optimization of current waveform tailoring for magnetically driven isentropic compression experiments.

    PubMed

    Waisman, E M; Reisman, D B; Stoltzfus, B S; Stygar, W A; Cuneo, M E; Haill, T A; Davis, J-P; Brown, J L; Seagle, C T; Spielman, R B

    2016-06-01

    The Thor pulsed power generator is being developed at Sandia National Laboratories. The design consists of up to 288 decoupled and transit time isolated capacitor-switch units, called "bricks," that can be individually triggered to achieve a high degree of pulse tailoring for magnetically driven isentropic compression experiments (ICE) [D. B. Reisman et al., Phys. Rev. Spec. Top.-Accel. Beams 18, 090401 (2015)]. The connecting transmission lines are impedance matched to the bricks, allowing the capacitor energy to be efficiently delivered to an ICE strip-line load with peak pressures of over 100 GPa. Thor will drive experiments to explore equation of state, material strength, and phase transition properties of a wide variety of materials. We present an optimization process for producing tailored current pulses, a requirement for many material studies, on the Thor generator. This technique, which is unique to the novel "current-adder" architecture used by Thor, entirely avoids the iterative use of complex circuit models to converge to the desired electrical pulse. We begin with magnetohydrodynamic simulations for a given material to determine its time dependent pressure and thus the desired strip-line load current and voltage. Because the bricks are connected to a central power flow section through transit-time isolated coaxial cables of constant impedance, the brick forward-going pulses are independent of each other. We observe that the desired equivalent forward-going current driving the pulse must be equal to the sum of the individual brick forward-going currents. We find a set of optimal brick delay times by requiring that the L2 norm of the difference between the brick-sum current and the desired forward-going current be a minimum. We describe the optimization procedure for the Thor design and show results for various materials of interest. PMID:27370469

  2. Towards reduced impact of EUV mask defectivity on wafer

    NASA Astrophysics Data System (ADS)

    Jonckheere, R.; Van den Heuvel, D.; Pacco, A.; Pollentier, I.; Baudemprez, B.; Jehoul, C.; Hermans, J.; Hendrickx, E.

    2014-07-01

    The defectivity challenges of extreme ultraviolet (EUV) masks, that need to be addressed before production readiness of EUV lithography is assured from the mask perspective, are twofold. First, the EUV-specific defect type relating to the multi-layer (ML) mirror, the so-called ML-defects, require to become more detectable than they are printable. This not only requires proven capability of blank inspection, but also the existence of satisfactory printability mitigation strategies (comprising avoidance, pattern shift methodology, compensation repair). Both these assets need to become available within the mask supply chain, as there is little that can still be done about such residual defects at the wafer fab. In a production phase, finding unexpected printing ML-defects is unacceptable. It is shown how the specific way-of-working in use at imec, starting from the printed wafer, contributes to related learning and identification of remaining gaps, in getting this issue fully dealt with. The second challenge relates to particle contamination during use of the reticle at the wafer fab. Avoiding overlaycritical particles on the backside of NXE3100 reticles is facilitated by the established way-of-working. Minimizing the occurrence of particles "hopping" between reticles via the electrostatic clamp of the scanner (so-called clamp-traveling particles) is a major driver for appropriate mask cleaning. The latter may not have negative impact by frequent use, in view of the highly vulnerable EUV mask stack, and especially for the present "black-border" solution in which the ML is etched away at the image border on the reticle. A lot of effort is spent into monitoring of NXE3100 reticles for particle adders on the pattern side. This is realized by comparing past and present mask defect maps obtained by inspection of printed wafers with subsequent repeater analysis.

  3. Method and apparatus for enhancing microchannel plate data

    DOEpatents

    Thoe, R.S.

    1983-10-24

    A method and apparatus for determining centroid channel locations are disclosed for use in a system activated by one or more multichannel plates and including a linear diode array providing channels of information 1, 2, ...,n, ..., N containing signal amplitudes A/sub n/. A source of analog A/sub n/ signals, and a source of digital clock signals n, are provided. Non-zero A/sub n/ values are detected in a discriminator. A digital signal representing p, the value of n immediately preceding that whereat A/sub n/ takes its first non-zero value, is generated in a scaler. The analog A/sub n/ signals are converted to digital in an analog to digital converter. The digital A/sub n/ signals are added to produce a digital ..sigma..A/sub n/ signal in a full adder. Digital 1, 2, ..., m signals representing the number of non-zero A/sub n/ are produced by a discriminator pulse counter. Digital signals representing 1 A/sub p+1/, 2 A/sub p+2/, ..., m A/sub p+m/ are produced by pairwise multiplication in multiplier. These signal are added in multiplier summer to produce a digital ..sigma..nA/sub n/ - p..sigma..A/sub n/ signal. This signal is divided by the digital ..sigma..A/sub n/ signal in divider to provide a digital (..sigma..nA/sub n//..sigma..A/sub n/) -p signal. Finally, this last signal is added to the digital p signal in an offset summer to provide ..sigma..nA/sub n//..sigma..A/sub n/, the centroid channel locations.

  4. Method and apparatus for enhancing microchannel plate data

    DOEpatents

    Thoe, Robert S.

    1987-01-01

    A method and apparatus for determining centroid channel locations is disclosed for use in a system activated by one or more multichannel plates (16,18) and including a linear diode array (24) providing channels of information 1, 2, . . . , n, . . . , N containing signal amplitudes A.sub.n. A source of analog A.sub.n signals (40), and a source of digital clock signals n (48), are provided. Non-zero A.sub.n values are detected in a discriminator (42). A digital signal representing p, the value of n immediately preceding that whereat A.sub.n takes its first non-zero value, is generated in a scaler (50). The analog A.sub.n signals are converted to digital in an analog to digital converter (44). The digital A.sub.n signals are added to produce a digital .SIGMA.A.sub.n signal in a full adder (46). Digital 1, 2, . . . , m signals representing the number of non-zero A.sub.n are produced by a discriminator pulse counter (52). Digital signals representing 1 A.sub.p+ 1, 2 A.sub.p+2, . . . , m A.sub.p+m are produced by pairwise multiplication in multiplier (54). These signals are added in multiplier summer (56) to produce a digital .SIGMA.nA.sub.n -p.SIGMA.A.sub.n signal. This signal is divided by the digital .SIGMA.A.sub.n signal in divider (58) to provide a digital (.SIGMA.nA.sub.n /.SIGMA.A.sub.n) -p signal. Finally, this last signal is added to the digital p signal in an offset summer (60) to provide .SIGMA.nA.sub.n /.SIGMA.A.sub.n, the centroid channel locations.

  5. Some anomalous behaviour of vertebrates and insects preceding M5+ earthquakes in the North Western Apennines (Italy)

    NASA Astrophysics Data System (ADS)

    Straser, Valentino

    2013-04-01

    Earthquakes with a magnitude greater than M5+ are an unusual event in the seismic area of the Frignano District and the areas surrounding Parma in the North Western Apennines (Italy). Only two seismic events have occurred in the last four years: on 23 December 2008 (M5.1) and on 27 January 2012 (M5.4). The earthquake of 23 December 2008 allowed the verification of unusual behaviour in man and animals in the run-up to the main shock, in addition to anomalies of an electromagnetic type. An initial study showed that there are elements of coincidence between the seismic events and the number of admissions to hospitals around the epicentre: in the month of December 2008, the days with the greatest number of admissions coincided with seismic shocks. A half hour before the main event of 23 December, recorded at 16:24:21 local time (see: INGV), a slowworm (Anguis fragilis) left its hibernation site and died shortly afterwards from the cold on a road, as did a viper (Vipera aspis) found near some dwellings in an area around twenty kilometres from the epicentre. The investigation proceeded in 2009, but this time based on the number of daily admissions to the hospital A&E department, between June and December 2009. During the six months of the investigation, the maximum number of emergencies was 9 per day, while the earthquakes were in line with the usual number and magnitude for the Frignano seismic district. The earthquakes from June to December 2009 numbered 10, with a magnitude from M2.5 to M3.6. In 8 cases, in the 48 hours preceding the occurrence of the seism, there was a greater number of hospital emergencies. The subsequent occasion to check on a possible relationship between anomalous behaviour in animals and a seism occurred on 27 January 2012 (see: INGV), when an earthquake with a magnitude of M5.4 shook the North Western Apennines, thankfully without resulting in victims. Like 2008, in an area around fifteen kilometres from the epicentre, a grass snake (Zamenis

  6. Climate and environment of the earliest West European hominins inferred from amphibian and squamate reptile assemblages: Sima del Elefante Lower Red Unit, Atapuerca, Spain

    NASA Astrophysics Data System (ADS)

    Blain, Hugues-Alexandre; Bailon, Salvador; Cuenca-Bescós, Gloria; Bennàsar, Maria; Rofes, Juan; López-García, Juan Manuel; Huguet, Rosa; Arsuaga, Juan Luis; Bermúdez de Castro, José Maria; Carbonell, Eudald

    2010-11-01

    The Sima del Elefante cave, in the Sierra de Atapuerca (Burgos, Spain), is famous for the fact that level TE9 of its Lower Red Unit recently delivered the oldest hominin remains of Western Europe, identified as Homo antecessor and dated by biostratigraphy and radiometric methods to ca 1.2 Ma. Given the importance of this discovery, every effort is being made to reconstruct the landscapes where these hominins once thrived. The amphibian and squamate reptile assemblage of the Sima del Elefante Lower Red Unit is here studied for the first time. The faunal list comprises at least 17 species (roughly 12,000 bone fossil remains): Salamandra salamandra, Triturus cf. marmoratus, Alytes obstetricans, Pelobates cultripes, Pelodytes punctatus, Bufo bufo, Bufo calamita, Hyla arborea, Rana sp., cf. Pelophylax sp., Lacerta s.l., small-sized indeterminate lacertids, Anguis fragilis, Natrix cf. natrix, Natrix cf. maura, Coronella cf. girondica and Vipera sp. As the amphibians and squamate reptiles do not differ at species level from the extant herpetofauna of the Iberian Peninsula, they can contribute to the reconstruction of the landscape and climate. In this paper, the mutual climatic range and habitat weighting methods are applied to the amphibian and squamate reptile assemblages in order to estimate quantitative data. The results from the squamate and amphibian study indicate that during the hominin presence the mean annual temperature (MAT = 10-13 °C) was always slightly warmer than at present and the mean annual precipitation (MAP = 800-1000 mm) was greater than today in the Burgos area. The landscape had open habitats in the vicinity of the Atapuerca caves throughout the sequence, with wet points in the surrounding area, and a predominance of humid meadows and open woodlands. These results mainly agree with those for large mammals, small mammals and the pollen analysis. The climate and landscape of TE-LRU are very similar to those reconstructed for the TD6 "Aurora Stratum

  7. Advances in CO2 cryogenic aerosol technology for photomask post AFM repair

    NASA Astrophysics Data System (ADS)

    Bowers, Charles; Varghese, Ivin; Balooch, Mehdi; Rodriguez, Jaime

    2009-10-01

    As the mask technology moves towards production of 36 nm and 22 nm DRAM half pitch nodes, printing features and sub-resolution assist features (SRAF) shrink below 80 nm. These narrow features become more fragile and place new demands on cleaning processes for a physically non damaging solution. These challenges include compatibility with new materials, oxidation, chemical contamination sensitivity, proportionally decreasing printable defect size, and a requirement for a damage-free clean. CO2 cryogenic aerosol cleaning has, for many years, shown potential to offer a wide process window for meeting some of these new challenges. CO2 cryogenic aerosol cleaning for post AFM repair debris cleaning has been used for many years on masks greater than 90 nm DRAM half pitch nodes. Until recently, CO2 purity and delivery hardware issues resulted in foreign material adder (FMACO2) contamination and SRAF damage below 150 nm critical feature size. Some key desirable properties of CO2 cryogenic aerosol cleaning are the non-oxidizing and non-etching properties when compared to current chemical wet clean processes. In this paper, recent advancements of CO2 cryogenic aerosol cleaning technology are presented, highlighting improvements in the areas of FMACO2 reduction, lowering the critical feature size without damage, and electrostatic discharge (ESD) mitigation. Key aspects of successful CO2 cryogenic aerosol cleaning include the spray nozzle design, CO2 liquid purity, and integrated system design. The design of the nozzle directly controls the size, flux, and velocity of the CO2 snow particles. Methodology and measurements of the solid CO2 particle size and velocity distributions will be presented, and their responses to various control parameters will be discussed. FMACO2 mitigation can be achieved only through use of highly purified CO2 and careful materials selection of the delivery hardware. Recent advances in CO2 purity will be discussed and data shown. The mask cleaning

  8. Nanoscale Magnetic Materials for Energy-Efficient Spin Based Transistors

    NASA Astrophysics Data System (ADS)

    Incorvia, Jean Anne Currivan

    In this dissertation, I study the physical behavior of nanoscale magnetic materials and build spin-based transistors that encode information in magnetic domain walls. It can be argued that energy dissipation is the most serious problem in modern electronics, and one that has been resistant to a breakthrough. Wasted heat during computing both wastes energy and hinders further technology scaling. This is an opportunity for physicists and engineers to come up with creative solutions for more energy-efficient computing. I present the device we have designed, called domain wall logic (DW-Logic). Information is stored in the position of a magnetic domain wall in a ferromagnetic wire and read out using a magnetic tunnel junction. This hybrid design uses electrical current as the input and output, keeping the device compatible with charge- based transistors. I build an iterative model to predict both the micromagnetic and circuit behavior of DW- Logic, showing a single device can operate as a universal gate. The model shows we can build complex circuits including an 18-gate Full Adder, and allows us to predict the device switching energy compared to complementary metal-oxide semiconductor (CMOS) transistors. Comparing ?15 nm feature nodes, I find DW-Logic made with perpendicular magnetic anisotropy materials, and utilizing both spin torque transfer and the Spin Hall effect, could operate with 1000x reduced switching energy compared to CMOS. I fabricate DW-Logic device prototypes and show in experiment they can act as AND and NAND gates. I demonstrate that one device can drive two subsequent devices, showing gain, which is a necessary requirement for fanout. I also build a clocked ring oscillator circuit to demonstrate successful bit propagation in a DW-Logic circuit and show that properly scaled devices can have improved operation. Through building the devices, I develop a novel fabrication method for patterning sub-25 nm magnetic wires with very low (˜ 2 nm) average edge

  9. Cross-Neutralisation of In Vitro Neurotoxicity of Asian and Australian Snake Neurotoxins and Venoms by Different Antivenoms

    PubMed Central

    Silva, Anjana; Hodgson, Wayne C.; Isbister, Geoffrey K.

    2016-01-01

    There is limited information on the cross-neutralisation of neurotoxic venoms with antivenoms. Cross-neutralisation of the in vitro neurotoxicity of four Asian and four Australian snake venoms, four post-synaptic neurotoxins (α-bungarotoxin, α-elapitoxin-Nk2a, α-elapitoxin-Ppr1 and α-scutoxin; 100 nM) and one pre-synaptic neurotoxin (taipoxin; 100 nM) was studied with five antivenoms: Thai cobra antivenom (TCAV), death adder antivenom (DAAV), Thai neuro polyvalent antivenom (TNPAV), Indian Polyvalent antivenom (IPAV) and Australian polyvalent antivenom (APAV). The chick biventer cervicis nerve-muscle preparation was used for this study. Antivenom was added to the organ bath 20 min prior to venom. Pre- and post-synaptic neurotoxicity of Bungarus caeruleus and Bungarus fasciatus venoms was neutralised by all antivenoms except TCAV, which did not neutralise pre-synaptic activity. Post-synaptic neurotoxicity of Ophiophagus hannah was neutralised by all antivenoms, and Naja kaouthia by all antivenoms except IPAV. Pre- and post-synaptic neurotoxicity of Notechis scutatus was neutralised by all antivenoms, except TCAV, which only partially neutralised pre-synaptic activity. Pre- and post-synaptic neurotoxicity of Oxyuranus scutellatus was neutralised by TNPAV and APAV, but TCAV and IPAV only neutralised post-synaptic neurotoxicity. Post-synaptic neurotoxicity of Acanthophis antarcticus was neutralised by all antivenoms except IPAV. Pseudonaja textillis post-synaptic neurotoxicity was only neutralised by APAV. The α-neurotoxins were neutralised by TNPAV and APAV, and taipoxin by all antivenoms except IPAV. Antivenoms raised against venoms with post-synaptic neurotoxic activity (TCAV) cross-neutralised the post-synaptic activity of multiple snake venoms. Antivenoms raised against pre- and post-synaptic neurotoxic venoms (TNPAV, IPAV, APAV) cross-neutralised both activities of Asian and Australian venoms. While acknowledging the limitations of adding antivenom prior to

  10. Surface-confined assemblies and polymers for molecular logic.

    PubMed

    de Ruiter, Graham; van der Boom, Milko E

    2011-08-16

    Stimuli responsive materials are capable of mimicking the operation characteristics of logic gates such as AND, OR, NOR, and even flip-flops. Since the development of molecular sensors and the introduction of the first AND gate in solution by de Silva in 1993, Molecular (Boolean) Logic and Computing (MBLC) has become increasingly popular. In this Account, we present recent research activities that focus on MBLC with electrochromic polymers and metal polypyridyl complexes on a solid support. Metal polypyridyl complexes act as useful sensors to a variety of analytes in solution (i.e., H(2)O, Fe(2+/3+), Cr(6+), NO(+)) and in the gas phase (NO(x) in air). This information transfer, whether the analyte is present, is based on the reversible redox chemistry of the metal complexes, which are stable up to 200 °C in air. The concurrent changes in the optical properties are nondestructive and fast. In such a setup, the input is directly related to the output and, therefore, can be represented by one-input logic gates. These input-output relationships are extendable for mimicking the diverse functions of essential molecular logic gates and circuits within a set of Boolean algebraic operations. Such a molecular approach towards Boolean logic has yielded a series of proof-of-concept devices: logic gates, multiplexers, half-adders, and flip-flop logic circuits. MBLC is a versatile and, potentially, a parallel approach to silicon circuits: assemblies of these molecular gates can perform a wide variety of logic tasks through reconfiguration of their inputs. Although these developments do not require a semiconductor blueprint, similar guidelines such as signal propagation, gate-to-gate communication, propagation delay, and combinatorial and sequential logic will play a critical role in allowing this field to mature. For instance, gate-to-gate communication by chemical wiring of the gates with metal ions as electron carriers results in the integration of stand-alone systems: the

  11. Associative memory architecture for word-parallel smallest Euclidean distance search using distance mapping into clock-number domain

    NASA Astrophysics Data System (ADS)

    Akazawa, Toshinobu; Sasaki, Seiryu; Jürgen Mattausch, Hans

    2014-01-01

    A scalable word-parallel associative memory for smallest Euclidean distance (ED) search is presented. Due to the applied concept of distance to clock-number mapping, the reported architecture is digital in nature and scalable to advanced technology. Furthermore, the reference data of feature vectors can be scaled in principle to any vector dimension and number. Handling of the numerical complexity of the ED without large consumption of Silicon area is achieved by an area-efficient circuit, which uses the same adder for absolute-difference calculation of vector components and subsequent square calculation by sequential addition of partial products. Additionally, a clock-number minimization algorithm is proposed to significantly reduce the clock-number needed for the search when the smallest ED is a large value. The concept of the proposed architecture has been experimentally verified by measurement results from real chips fabricated in a 180 nm CMOS technology, in which the architecture is configured for parallel smallest ED search among 32 reference vectors with each vector having 16 8-bit elements. For the application example of codebook-based data compression, the fabricated test chip achieved 1.19 µs average search time, 5.77 µs worst-case search time and low power consumption of 8.75 mW at the maximum clock frequency of 47 MHz and nominal power supply voltage Vdd = 1.8 V. At reduced power supply voltage Vdd = 1.2 V, a smaller power consumption of 2.80 mW at an also smaller maximum clock frequency of 24 MHz is measured. In comparison to previous analog-digital architecture, a reduction of the normalized power-delay product per matching operation by about a factor 1.6 at Vdd = 1.8 V (about factor 2.5 at Vdd = 1.2 V) is obtained with best-case data for the analog-digital architecture and average-case data for the proposed fully-digital architecture.

  12. Block QCA Fault-Tolerant Logic Gates

    NASA Technical Reports Server (NTRS)

    Firjany, Amir; Toomarian, Nikzad; Modarres, Katayoon

    2003-01-01

    Suitably patterned arrays (blocks) of quantum-dot cellular automata (QCA) have been proposed as fault-tolerant universal logic gates. These block QCA gates could be used to realize the potential of QCA for further miniaturization, reduction of power consumption, increase in switching speed, and increased degree of integration of very-large-scale integrated (VLSI) electronic circuits. The limitations of conventional VLSI circuitry, the basic principle of operation of QCA, and the potential advantages of QCA-based VLSI circuitry were described in several NASA Tech Briefs articles, namely Implementing Permutation Matrices by Use of Quantum Dots (NPO-20801), Vol. 25, No. 10 (October 2001), page 42; Compact Interconnection Networks Based on Quantum Dots (NPO-20855) Vol. 27, No. 1 (January 2003), page 32; Bit-Serial Adder Based on Quantum Dots (NPO-20869), Vol. 27, No. 1 (January 2003), page 35; and Hybrid VLSI/QCA Architecture for Computing FFTs (NPO-20923), which follows this article. To recapitulate the principle of operation (greatly oversimplified because of the limitation on space available for this article): A quantum-dot cellular automata contains four quantum dots positioned at or between the corners of a square cell. The cell contains two extra mobile electrons that can tunnel (in the quantummechanical sense) between neighboring dots within the cell. The Coulomb repulsion between the two electrons tends to make them occupy antipodal dots in the cell. For an isolated cell, there are two energetically equivalent arrangements (denoted polarization states) of the extra electrons. The cell polarization is used to encode binary information. Because the polarization of a nonisolated cell depends on Coulomb-repulsion interactions with neighboring cells, universal logic gates and binary wires could be constructed, in principle, by arraying QCA of suitable design in suitable patterns. Heretofore, researchers have recognized two major obstacles to realization of QCA

  13. CD forecasting in resist by means of scatterometry

    NASA Astrophysics Data System (ADS)

    Richter, Jan

    2010-05-01

    Critical dimension (CD) targeting is one of the key process parameters for the disposition of photomasks. The specifications are tightened at a constant rate over the years and are currently in the range of 3 nm for the most critical layers. Many efforts have been put in prediction of the critical dimension that is targeting the actual product based on data of previous products and also using resist data for further analysis and correction cycles. So far the tool of choice was the CD SEM (scanning electron microscope) with significant shortcomings due to altering the resist and its defect criticality during resist measurement. Here we present data of long term resist CD monitoring on an n&k CDRT 5700 scatterometer system measuring standard mask patterns in the non-active field. Presented are results for one resist on two different photomask stack materials. The data is compared with the final CD measurement by CD SEM. The data is correlated accounting for tool variances in the manufacturing process and the mask clear field loading. The resulting model is still fairly simple with only 4 parameters for each process of record, one of them for the slope of CD values between CD SEM and n&k and three offsets for different process variables. The data shows stable model behavior over close to one year including several resist lot changes and significant drifts in the front end process. The maximum forecast error is slightly above 2 nm and the process has a 95% capability to predict mean to target values better than 2 nm. Furthermore, the defect level has shown to be constant during that time frame with not a single incidence of particles due to the usage of the scatterometer. The total cycle time impact is minimal because only 4 points are recorded thus loading and unloading the mask to the tool is the actual cycle time adder. The described method is capable to significantly improve the CD targeting performance due to better partitioning of processes.

  14. The repetitive high energy pulsed power module

    SciTech Connect

    Harjes, H.C.; Reed, K.W.; Buttram, M.T.; Turman, B.N.; Neau, E.L.; Martinez, L.; Adcock, J.; Weinbrecht, E.A.; Mann, G.A.; Morgan, F.A.; Laderach, G.E.; Pena, G.; Butler, M.; Schneider, L.X.; Wavrik, R.W.; Penn, K.J.; Weber, G.J.

    1990-01-01

    High average power magnetic pulse compression systems are being considered for use in several applications. One of the key issues in the design of a pulsed power driver for these applications is component reliability, efficiency, and lifetime. In the Repetitive High Energy Pulsed Power (RHEPP) module, pulse compression is done exclusively with magnetic switches (saturable reactors) because such switches have the potential of performing efficiently and reliably for >10{sup 10} shots. The objective of the RHEPP project is to explore the feasibility of using magnetic pulse compression technology in continuous high average power applications. The RHEPP system consists of a compressor which drives a linear induction voltage adder with a diode load. Prime power for the module is supplied by a 600 kW, 120 Hz, alternator (furnished by Westinghouse Electric Corporation). At present, construction and initial testing in a bipolar mode of the first two stages of the compressor has been completed. This system has operated for a total of 332 minutes (4.8 {times} 10{sup 6} pulses) at full power (600 kW) with an efficiency of 94+/{minus}3%. The first stage magnetic switch (MS1) has a pulse compression factor of 8.4 (4.2 ms to 500 {mu}s time to peak). It has two, parallel connected, 67 turn copper coils and a 760 kg core of 2 mil silicon steel with a magnetic cross sectional area of 0. 065 m{sup 2}. The second stage magnetic switch (MS2) has a pulse compression factor of 3 (500 {mu}s to 170 {mu}s). It has two, parallel connected, 36 turn copper coils and a 361 kg core of field annealed 2605CO Metglas with a magnetic area of 0.019 m{sup 2}. A discussion of RHEPP compressor design effort and its baseline design is given. In addition, initial results from the operation of the first two stages are presented. 11 refs., 8 figs., 4 tabs.

  15. Physical and timing verification of subwavelength-scale designs: I. Lithography impact on MOSFETs

    NASA Astrophysics Data System (ADS)

    Pack, Robert C.; Axelrad, Valery; Shibkov, Andrei; Boksha, Victor V.; Huckabay, Judy A.; Salik, Rachid; Staud, Wolfgang; Wang, Ruoping; Grobman, Warren D.

    2003-07-01

    Subwavelength lithography at low contrast, or low-k1 factor, leads to new requirements for design, design analysis, and design verification techniques. These techniques must account for inherent physical circuit feature distortions resulting from layout pattern-dependent design-to-silicon patterning processes in this era. These distortions are unavoidable, even in the presence of sophisticated Resolution Enhancement Technologies (RET), and are a 'fact-of-life" for the designer implementing nanometer-scale designs for the foreseeable low-k1 future. The consequence is that fabricated silicon feature shapes and dimensions are in general printed with far less fidelity in comparison to the designer"s desired layout than in past generations and that the designer must consider design within significantly different margins of geometry tolerance. Traditional (Mead-Conway originated) WYSIWYG (what you see is what you get) design methodologies, assume that the designer"s physical circuit element shapes are accurate in comparison to the corresponding shapes on the real fabricated IC, and uses design rules to verify satisfactory fabrication compliance, as the input for both interconnect parasitic loading calculations and to transistor models used for performance simulation. However, these assumptions are increasingly poor ones as k1 decreases to unprecidented levels -- with concomitant increase in patterned feature distortion and fabrication yield failure modes. This paper explores a new paradigm for nanometer-scale design, one in which more advanced models of critical low-k1 lithographic printing effects are incorporated into the design flow to improve upon yield and performance verification accuracy. We start with an analysis of a complex 32-bit adder block circuit design to determine systematic changes in gate length, width and shape variations for each MOSFET in the circuit due to optical proximity effects. The physical gate dimensions for all, as predicted by the

  16. Analysis of camelid antibodies for antivenom development: Neutralisation of venom-induced pathology.

    PubMed

    Cook, Darren A N; Owen, Timothy; Wagstaff, Simon C; Kinne, Joerg; Wernery, Ulrich; Harrison, Robert A

    2010-09-01

    Camelid IgG has been reported to be less immunogenic, less able to activate the complement cascade and more thermostable than IgG from other mammals, and has the ability to bind antigens that are unreactive with other mammalian IgGs. We are investigating whether these attributes of camelid IgG translate into antivenom with immunological and venom-neutralising efficacy advantages over conventional equine and ovine antivenoms. The objective of this study was to determine the preclinical venom-neutralising effectiveness of IgG from camels immunised with venoms, individually or in combination, of the saw-scaled viper, Echis ocellatus, the puff adder, Bitis arietans and the spitting cobra, Naja nigricollis - the most medically-important snake species in West Africa. Neutralisation of the pathological effects of venoms from E. ocellatus, B. arietans and N. nigricollis by IgG from the venom-immunised camels, or commercial antivenom, was compared using assays of venom lethality (ED(50)), haemorrhage (MHD) and coagulopathy (MCD). The E. ocellatus venom ED(50), MHD and MCD results of the E. ocellatus monospecific camel IgG antivenom were broadly equivalent to comparable ovine (EchiTAbG, MicroPharm Ltd, Wales) and equine (SAIMR Echis, South African Vaccine Producer, South Africa) antivenoms, although the equine antivenom required half the amount of IgG. The B. arietans monospecific camel IgG neutralised the lethal effects of B. arietans venom at one fourth the concentration of the SAIMR polyspecific antivenom (a monospecific B. arietans antivenom is not available). The N. nigricollis camel IgG antivenom was ineffective (at the maximum permitted dose, 100 mul) against the lethal effects of N. nigricollis venom. All the equine polyspecific antivenoms required more than 100 microl to be effective against this venom. The polyspecific camel IgG antivenom, prepared from five camels, was effective against the venom-induced effects of E. ocellatus but not against that of B. arietans

  17. Novel nanowire heterostructures for nanoelectronic applications

    NASA Astrophysics Data System (ADS)

    Yan, Hao

    Semiconductor nanowires are promising candidates for future nanoelectronic devices. Integration of functional materials into nanowires in the form of nanowire heterostructures can give them unique properties and novel device applications. This thesis deals with the synthesis, characterization and electronic application of core/shell nanowire heterostructures. First, a novel approach to the core/shell heterostructure, namely the atomic layer deposition (ALD) is introduced to deposit high-dielectric-constant (high-k) oxide, perovskite oxide and metal. The excellent conformality of ALD allows these materials to form uniform shells on semiconductor nanowire cores. The electrical and magnetic properties of Si/ZrO2/Ni core/shell/shell nanowires are further investigated, which shows metallic conductivity and axial alignment in a magnetic field. Next, we study the performance of semiconductor/high-k-oxide core/shell nanowires as nanowire field effect transistors (NW-FETs). The fabrication strategies are first evaluated. Then high-performance NW-FET devices with large ON/OFF ratio, sharp switching and low leakage current are demonstrated. These devices show significant gate enhancement compared to the back-gated devices and are promising to outperform state-of-the-art planar MOSFETs fabricated with top-down methods. Subsequently, a charge-trapping nanowire (CTNW) with semiconductor/multidielectric core/shell heterostructure is demonstrated. Charge-trapping in the nanowire heterostructure gives it memory function with large ON/OFF ratio and reliable switching. Charge-trapping also defines the gate response of the CTNW-FET, making it a programmable logic unit. Furthermore, the application of the CTNW heterostructure in neuromorphic circuit is investigated. CTNWs are then built into crossbar array architecture to carry out complex functions. Programming different active node patterns into the array allows it to carry out different logic operations such as XOR, adder

  18. P-23 Highlights 6/10/12: Cygnus Dual Beam Radiographic Facility Refurbishment completed at U1A tunnel in Nevada NNSS meeting Level 2 milestone

    SciTech Connect

    Deyoung, Anemarie; Smith, John R.

    2012-05-03

    A moratorium was placed on U.S. underground nuclear testing in 1992. In response, the Stockpile Stewardship Program was created to maintain readiness of the existing nuclear inventory through several efforts such as computer modeling, material analysis, and subcritical nuclear experiments (SCEs). As in the underground test era, the Nevada National Security Site (NNSS), formerly the Nevada Test Site, provides a safe and secure environment for SCEs by the nature of its isolated and secure facilities. A major tool for SCE diagnosis installed in the 05 drift laboratory is a high energy x-ray source used for time resolved imaging. This tool consists of two identical sources (Cygnus 1 and Cygnus 2) and is called the Cygnus Dual Beam Radiographic Facility (Figs. 2-6). Each Cygnus machine has 5 major elements: Marx Generator, Pulse Forming Line (PFL), Coaxial Transmission Line (CTL), 3-cell Inductive Voltage Adder (IVA), and Rod Pinch Diode. Each machine is independently triggered and may be fired in separate tests (staggered mode), or in a single test where there is submicrosecond separation between the pulses (dual mode). Cygnus must operate as a single shot machine since on each pulse the diode electrodes are destroyed. The diode is vented to atmosphere, cleaned, and new electrodes are inserted for each shot. There is normally two shots per day on each machine. Since its installation in 2003, Cygnus has participated in: 4 Subcritical Experiments (Armando, Bacchus, Barolo A, and Barolo B), a 12 shot plutonium physics series (Thermos), and 2 plutonium step wedge calibration series (2005, 2011), resulting in well over 1000 shots. Currently the Facility is in preparation for 2 SCEs scheduled for this calendar year - Castor and Pollux. Cygnus has performed well during 8 years of operations at NNSS. Many improvements in operations and performance have been implemented during this time. Throughout its service at U1a, major maintenance and replacement of many hardware items

  19. Extending CO2 cryogenic aerosol cleaning for advanced optical and EUV mask cleaning

    NASA Astrophysics Data System (ADS)

    Varghese, Ivin; Bowers, Charles W.; Balooch, Mehdi

    2011-11-01

    Cryogenic CO2 aerosol cleaning being a dry, chemically-inert and residue-free process is used in the production of optical lithography masks. It is an attractive cleaning option for the mask industry to achieve the requirement for removal of all printable soft defects and repair debris down to the 50nm printability specification. In the technique, CO2 clusters are formed by sudden expansion of liquid from high to almost atmospheric pressure through an optimally designed nozzle orifice. They are then directed on to the soft defects or debris for momentum transfer and subsequent damage free removal from the mask substrate. Unlike aggressive acid based wet cleaning, there is no degradation of the mask after processing with CO2, i.e., no critical dimension (CD) change, no transmission/phase losses, or chemical residue that leads to haze formation. Therefore no restriction on number of cleaning cycles is required to be imposed, unlike other cleaning methods. CO2 aerosol cleaning has been implemented for several years as full mask final clean in production environments at several state of the art mask shops. Over the last two years our group reported successful removal of all soft defects without damage to the fragile SRAF features, zero adders (from the cleaning and handling mechanisms) down to a 50nm printability specification. In addition, CO2 aerosol cleaning is being utilized to remove debris from Post-RAVE repair of hard defects in order to achieve the goal of no printable defects. It is expected that CO2 aerosol cleaning can be extended to extreme ultraviolet (EUV) masks. In this paper, we report advances being made in nozzle design qualification for optimum snow properties (size, velocity and flux) using Phase Doppler Anemometry (PDA) technique. In addition the two new areas of focus for CO2 aerosol cleaning i.e. pellicle glue residue removal on optical masks, and ruthenium (Ru) film on EUV masks are presented. Usually, the residue left over after the pellicle

  20. Recyclable transmission line (RTL) and linear transformer driver (LTD) development for Z-pinch inertial fusion energy (Z-IFE) and high yield.

    SciTech Connect

    Sharpe, Robin Arthur; Kingsep, Alexander S. (Kurchatov Institute, Moscow, Russia); Smith, David Lewis; Olson, Craig Lee; Ottinger, Paul F. (Naval Research Laboratory, Washington, DC); Schumer, Joseph Wade (Naval Research Laboratory, Washington, DC); Welch, Dale Robert (Voss Scientific, Albuquerque, NM); Kim, Alexander (High Currents Institute, Tomsk, Russia); Kulcinski, Gerald L. (University of Wisconsin, Madison, WI); Kammer, Daniel C. (University of Wisconsin, Madison, WI); Rose, David Vincent (Voss Scientific, Albuquerque, NM); Nedoseev, Sergei L. (Kurchatov Institute, Moscow, Russia); Pointon, Timothy David; Smirnov, Valentin P.; Turgeon, Matthew C.; Kalinin, Yuri G. (Kurchatov Institute, Moscow, Russia); Bruner, Nichelle "Nicki" (Voss Scientific, Albuquerque, NM); Barkey, Mark E. (University of Alabama, Tuscaloosa, AL); Guthrie, Michael (University of Wisconsin, Madison, WI); Thoma, Carsten (Voss Scientific, Albuquerque, NM); Genoni, Tom C. (Voss Scientific, Albuquerque, NM); Langston, William L.; Fowler, William E.; Mazarakis, Michael Gerrassimos

    2007-01-01

    demonstrated at the SNL Z-IFE LTD laboratory with rep-rates up to 10.3 seconds between shots (this is essentially at the goal of 10 seconds for Z-IFE). (7) A single LTD switch at Tomsk was fired repetitively every 12 seconds for 36,000 shots with no failures. (8) Five 1.0 MA, 100 kV, 100 ns, LTD cavities have been combined into a voltage adder configuration with a test load to successfully study the system operation. (9) The combination of multiple LTD coaxial lines into a tri-plate transmission line is examined. The 3D Quicksilver code is used to study the electron flow losses produced near the magnetic nulls that occur where coax LTD lines are added together. (10) Circuit model codes are used to model the complete power flow circuit with an inductive isolator cavity. (11) LTD architectures are presented for drivers for Z-IFE and high yield. A 60 MA LTD driver and a 90 MA LTD driver are proposed. Present results from all of these power flow studies validate the whole LTD/RTL concept for single-shot ICF high yield, and for repetitive-shot IFE.

  1. Nanoparticle removal using laser induced plasma (LIP) technique and study of detachment modes based on molecular dynamics simulations

    NASA Astrophysics Data System (ADS)

    Peri, M. D. Murthy

    Nanoparticle contamination is a major problem in many industries. In the semiconductor industry, as the device (integrated circuit) size shrinks with each technological node (DRAM half-pitch), the feature size that has to be fabricated shrinks. Consequently, the minimum tolerable particle defect size also reduces to sub-100 nm level. In order to attain the stringent small size features, Extreme Ultraviolet Lithography (EUVL) technique is being explored in the semiconductor industry. As the EUVL masks are reflective and pellicle free, the cleaning techniques employed to remove the native particle defects must be more effective for the removal of the sub-100 nm particles without any substrate damage. The effectiveness of Laser Induced Plasma (LIP) technique, considered as a next generation cleaning method, for removal of 30 nm PSL particles from silicon substrate was previously demonstrated by our group. In the current study, the removal of 100 nm PSL particles from photomask and 300 nm PSL particles from 500 nm patterns was investigated. It was observed that the patterns were damaged which could be attributed to the radiation heating of the plasma, and this necessitated pressure amplification techniques to amplify the transient pressure and minimize the risk of damage. As a potential solution, shocktubes were designed and transient pressure measurements were carried out in air medium. Also, plasma was generated in water, in order to take advantage of the density of the medium, to generate stronger shocks and consequently higher pressure. The performance of the shocktubes was characterized based on their pressure amplification factor. The shocktubes resulted in a pressure amplification factor of 11 in air. The particle removal experiments with shocktubes on 150 nm patterns were performed and no damage to the patterns was observed. However, there were particle adders due to the ablation of the shocktube material. Molecular Dynamics (MD) simulations were initiated and

  2. Wide Range SET Pulse Measurement

    NASA Technical Reports Server (NTRS)

    Shuler, Robert L.; Chen, Li

    2012-01-01

    A method for measuring a wide range of SET pulses is demonstrated. Use of dynamic logic, faster than ordinary CMOS, allows capture of short pulses. A weighted binning of SET lengths allows measurement of a wide range of pulse lengths with compact circuitry. A pulse-length-conservative pulse combiner tree routes SETs from combinational logic to the measurement circuit, allowing SET measurements in circuits that cannot easily be arranged in long chains. The method is applied to add-multiplex combinational logic, and to an array of NFET routing switches, at .35 micron. Pulses are captured in a chain of Domino Logic AND gates. Propagation through the chain is frozen on the trailing edge by dropping low the second "enable" input to the AND gates. Capacitive loading is increased in the latter stages to create an approximately logarithmic weighted binning, so that a broad range of pulse lengths can be captured with a 10 stage capture chain. Simulations show pulses can be captured which are 1/5th the length of those typically captured with leading edge triggered latch methods, and less than the length of those captured with a trailing edge latch method. After capture, the pulse pattern is transferred to an SEU protected shift register for readout. 64 instances of each of two types of logic are used as targets. One is a full adder with a 4 to 1 mux on its inputs. The other is a 4 x 4 NFET routing matrix. The outputs are passed through buffered XNOR comparators to identify pulses, which are merged in a buffered not-nand (OR) tree designed to avoid pulse absorption as much as possible. The output from each of the two test circuits are input into separate pulse measurement circuits. Test inputs were provided so that the circuit could be bench tested and calibrated. A third SET measurement circuit with no inputs was used to judge the contribution from direct hits on the measurement circuit. Heavy ions were used with an LET range from 12 to 176. At LET of 21 and below, the very

  3. Seasonal Fluxes and Cycling of Trace Metals in Semi-Arid Fluvial Systems: Leichhardt River, Queensland, Australia

    NASA Astrophysics Data System (ADS)

    Mackay, A. K.; Taylor, M. P.

    2007-12-01

    fluxes revealed two tributaries draining the MIM lease recorded the highest total (King Gully: Cd, 30, Cu, 3600, Pb, 3600, Zn, 4900 ug/L) and water soluble trace metal (Death Adder Creek: Cd, 17, Cu, 780, Pb, 61, Zn, 1500 ug/L) concentrations during the wet season flows. Concentrations were highest at the onset of the floods and although values decreased during the rising limb of the hydrograph, total and water soluble contaminants remained elevated with respect to Australian Government Guidelines and pose a potential environmental toxicology risk. Monitoring of the dry season pools commenced in February 2007 and showed highly variable water soluble trace metal concentrations ranging from below instrument detection to 140, 12, 12 and 7 ug/L for Zn, Pb, Cu and Cd, respectively. The highest concentrations were recorded towards the end of the dry season and within the pools adjacent to and downstream of the MIM lease. The results indicate that metal contaminants are predominately particulate bound during wet season flow and are removed from suspension upon capture and storage in Lake Moondarra and channel pools. The pool waters became more concentrated with soluble metal contaminants over the dry season and were controlled by evaporation and reduced pools size. Overall, sediment and water quality in the Leichhardt River and tributaries draining the MIM lease is seriously impaired with respect to Australian Government Guidelines. However, while it is clear that a potential environmental toxicology risk exists there remains an absence of ecotoxicological data examining the effects of metal contaminants on the biotic occupants of the system.

  4. An open-architecture approach to defect analysis software for mask inspection systems

    NASA Astrophysics Data System (ADS)

    Pereira, Mark; Pai, Ravi R.; Reddy, Murali Mohan; Krishna, Ravi M.

    2009-04-01

    possible for the end-users to make use of their collected knowledge through the years of experience in mask inspection process by encapsulating the knowledge into software utilities and plugging them into NxDAT. The plug-in interface is designed with the intent of enabling the pro-active mask defect analysis teams to build competitive differentiation into their defect analysis process while protecting their knowledge internally within their company. By providing interface with all major standard layout and mask data formats, NxDAT enables correlation of defect data on reticles with design and mask databases, further extending the effectiveness of defect analysis for D2DB inspection. NxDAT also includes many other advanced features for easy and fast navigation, visual display of defects, defect selection, multi-tier classification, defect clustering and gridding, sophisticated CD and contact measurement analysis, repeatability analysis such as adder analysis, defect trend, capture rate etc.