38,486 research outputs found
Joint Channel, Carrier-Frequency-Offset and Noise-Variance Estimation for OFDM Systems Based on Expectation Maximization
No full textIn this paper, a joint channel, carrier-frequency-offset (CFO) and noise-variance estimation scheme is proposed for OFDM systems which is based on Expectation and Maximization (EM) algorithm. The channel parameters are estimated using training sequences incorporated at the beginning of each transmission frame. Based on the assumption that the amplitude and CFO of different paths are independent, the received multipath components may be decomposed into independent data sets of the resolvable propagation paths. Hence the associated multi-dimensional minimization problem may be decomposed into separate single-dimensional minimization processes, the maximum likelihood and yet, remains capable of approaching performance at a significantly reduced complexity
FIRST-PRINCIPLES CALCULATIONS OF THE COULOMB PSEUDOPOTENTIAL MU-ASTERISK - APPLICATION TO AL
No full textWe present first-principles pseudopotential calculations for the Coulomb pseudopotential mu* using a dielectric matrix approach. An application to Al is made and mu* is estimated to be 0.091. A comparison of the crystal potential, local field, and exchange-correlation effects on the dielectric screening demonstrates that the exchange-correlation effect contributes the largest reduction in mu* compared to that obtained for a free electron gas
Metadata Representations for Queryable ML Model Zoos
No full textMachine learning (ML) practitioners and organizations are building model zoos of pre-trained models, containing metadata describing properties of the ML models and datasets that are useful for reporting, auditing, reproducibility, and interpretability purposes. The metatada is currently not standardised; its expressivity is limited; and there is no interoperable way to store and query it. Consequently, model search, reuse, comparison, and composition are hindered. In this paper, we advocate for standardized ML model metadata representation and management, proposing a toolkit supported to help practitioners manage and query that metadata.Web Information SystemsHuman-Centred Artificial Intelligenc
A Manifesto of Nodalism
No full textThis paper proposes the notion of Nodalism as a means describing contemporary culture and of understanding my own creative practice in electronic music composition. It draws on theories and ideas from Kirby, Bauman, Bourriaud, Deleuze, Guatarri, and Gochenour, to demonstrate how networks of ideas or connectionist neural models of cognitive behaviour can be used to contextualize, understand and become a creative tool for the creation of contemporary electronic music
Effect of tunicamycin on the activity and immunoreactivity of ascorbate oxidase (Cucurbita pepo medullosa) expressed in cultured green zucchini cells
No full textAscorbate oxidase activity and immunoreactivity were evaluated in crude tissue extracts obtained from callus cell cultures induced by green zucchini sarcocarp and grown in the presence of tunicamycin, a powerful N-glycosylation inhibitor. Tunicamycin at 2 or 4 mu g ml(-1) blocked cell growth within a couple of weeks, although a sustained cell viability was observed in the same period. A significant inhibition of total protein synthesis was observed at 10 and 15 days of culture time, with a decrease of 30% and 43% respectively when cells were grown in the presence of 2 mu g ml(-1) tunicamycin, and of 48% and 57% respectively when the tunicamycin concentration was 4 mu g ml(-1). After the same culture times ascorbate oxidase specific activity assayed in crude tissue extracts showed increases of about 1.9-fold and 3.5-fold (10 days) and 1.7-fold and 3.1-fold (15 days) at 2 and 4 mu g ml(-1) tunicamycin, respectively. Ascorbate oxidase mRNA levels, however, did not appreciably differ between control and treated samples, measured at the same growing times. Lectin-blot, based on the use of concanavalin A, indicated a marked decrease of glycosylated proteins in tunicamycin-treated cultures. As judged by immunoblot, anti-native ascorbate oxidase antibodies scarcely recognized the enzyme expressed in tunicamycin-treated cells; on the contrary, anti-deglycosylated ascorbate oxidase antibodies were more reactive to the enzyme expressed in tunicamycin-treated cultures
Francoism and the republican Eexiles: the case of the composer Julián Bautista (1901–61)
No full textExile studies in musicology have generally focused on Central European exiles fleeing from Nazism; at the same
time studies of the Republican exile following the Spanish Civil War have tended to deal primarily with writers
rather than musicians. This article intends to address both these areas of neglect by focusing on the composer
Julia´n Bautista, who settled in Buenos Aires in 1940. In the late 1950s, after more than a decade of oblivion in
his home country, Bautista, like other anti-Francoist exiles, started to become the object of interest again in
Spain, an interest which continued after the composer’s death in 1961. By exploring Bautista’s presence in the
Francoist musical press and in high-profile, state-sponsored events such as the Festivales de Música de América
y España, I shall explore the reasons for his rehabilitation – reasons that, far from amounting to straightforward
liberalization, seem to have been closely aligned with the strategies of the régime, and the cultural values and
historical narratives that underpinned them
Optimizing ML Inference Queries Under Constraints
No full textThe proliferation of pre-trained ML models in public Web-based model zoos facilitates the engineering of ML pipelines to address complex inference queries over datasets and streams of unstructured content. Constructing optimal plan for a query is hard, especially when constraints (e.g. accuracy or execution time) must be taken into consideration, and the complexity of the inference query increases. To address this issue, we propose a method for optimizing ML inference queries that selects the most suitable ML models to use, as well as the order in which those models are executed. We formally define the constraint-based ML inference query optimization problem, formulate it as a Mixed Integer Programming (MIP) problem, and develop an optimizer that maximizes accuracy given constraints. This optimizer is capable of navigating a large search space to identify optimal query plans on various model zoos.Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Web Information SystemsHuman-Centred Artificial Intelligenc
The impact of increasing the incinerator ash content on landfill site biostabilisation
No full textThe results of ash characterisation showed that the total carbon (TC) and total nitrogen (TN) in different sieved particle sizes increased as the particle size decreased. The average total content of the heavy metals Cu, Cd, Pb, Zn, Ni and Cr was 7786, 29, 994, 4006, 224 and 226 μgg-1 respectively. The leaching results of 10 g bottom ash mixed with 500 ml distilled water using tumbling and reciprocating shaking showed that the leaching concentration was in the range of 0~11 μgg-1. Leaching from the ash was greater at the extremes of pH and temperatures these having the greatest effect on leachate concentrations of Zn, Pb, and Cu. An inhibitory effect of heavy metals was shown at a 50% levels for Zn, Cu and Ni of 650mg Znl-1 dry solid sludge, 360 mg Cul-1 and 40 mg Cug-1 dry solid sludge and 380 mg Nil-1 and 39 mg Nig-1 dry solid sludge respectively. Bottom ash showed potential adsorption capacity for organic matter which was influenced by ash concentration, pH, temperature and particle size. the adsorption capacity increased as the ash concentration, pH, temperature, and particle size decreased. The anaerobic co-digestion of bottom ash and a simulated domestic refuse showed the beneficial effect of bottom ash addition. These studies were conducted in laboratory scale anaerobic digesters with a retention time of 20 days. Four reactors were used, two of these (controls) had no ash addition whilst the other two had ash added with the batch fed refuse simulant in a ration of 25/100 and 50/100 respectively.</p
Spinal anesthesia: comparison of isobaric ropivacaine (5 mg/ml) with isobaric bupivacaine (5 mg/ml)
No full textАдрес за кореспонденция: Д-р Дочка Цонева, дм, Клиника по анестезиология и ИЛ,
УМБАЛ „Александровска”, бул. „Св. Г. Софийски” № 1, 1431 София, e-mail: [email protected] ***** Address for correspondence: Dochka Tzoneva, M. D., Department of Anesthesiology and Intensive Care, University Hospital "Aleksandrovska", Medical University, 1, Sv. G. Sofyiski St., Bg - 1431 Sofia, e-mail: [email protected]Резюме: През последните години нарасна относителният дял на локорегионалните
методи на интраоперативно обезболяване и лечение на болката. Спиналната анестезия (СА) е популярна техника за обезболяване с висока успеваемост, добър профил на безопасност и е широко използвана в клиничната практика. Ропивакаин е нов амиден локален анестетик, синтезиран като чист S-енантиомер. Несъмнени негови достойнства са продължителното действие и възможността да се постигне диференциран сензомоторен блок при по-ниска системна токсичност. Целда се сравнят ефектите на еквипотентни дози изобарен ропивакаин (5 mg/ml) и изобарен бупивакаин (5 mg/ml), приложени интратекално за интраоперативно обезболяване
при възрастни пациенти. 34 възрастни пациенти, планирани за оперативно
лечение под СА по повод ингвинална херния и заболявания в аноректалната област, рандомизирано са разпределени в две групи в зависимост от прилагания локален анестетик: група R (ропивакаин; N = 17) и група B (бупивакаин; N = 17). Оценяваме начало и продължителност на сензорен и моторен блок; сегментно ниво на сензорен блок (дерматом); хемодинамични показатели; нежелани ефекти; време до първо уриниране. Ропивакаин
осигурява спинален блок с подобен клиничен профил както бупивакаин. Началото на сензорния блок е по-бързо, а продължителността 1,2 пъти по-дълга при пациентите в група B. При пациентите в група R по-рядко е наблюдаван пълен моторен блок; възстановяването от СА е 1,2 пъти по-
бързо, а времето до първо уриниране е 1,3 пъти по-кратко, в сравнение с пациентите в група В. Хемодинамичните промени са сходни в двете групи. В ранния постоперативен период нито един пациент не съобщава някакви
оплаквания. Изобарен ропивакаин (5 mg/ml) осигурява еквивалентна СА за операции по повод ингвинална херния и заболявания в аноректалната област с по-бързо възстановяване в сравнение с бупивакаин. Ропивакаин е локален анестетик с добра поносимост, ефективен за интраоперативно
обезболяване с минимално потискане на моторната функция и редуциран потенциал за кардио- и ЦНС токсичност. ***** Summary: Recently, the proportion of loco-regional methods of intraoperative analgesia
and pain management has increased. Spinal anesthesia (SA) is a popular,
widely used in clinical practice technique for analgesia with a high success rate
and good safety profile. Ropivacaine is a new amide local anesthetic, synthesized
as a pure S-enantiomer. Its unquestionable advantages are prolonged action
and the ability to achieve differential sensorimotor blockade with lower systemic toxicity. The aim of the study was to compare the effects of equipotent
doses of isobaric ropivacaine (5 mg/ml) to isobaric bupivacaine (5 mg/ml), administered
intrathecally for intraoperative analgesia in adult patients. Thirty-four adult patients scheduled for inguinal hernia repair and anorectal surgery under
intrathecal anesthesia were randomized in two groups according to the administrated
local anesthetic: group R (ropivacaine; N = 17) and group B (bupivacaine; N = 17). The onset, duration and segmental level of sensory and motor blockade
were examined, as well as hemodynamic variables, side effects, and time
to first void. The results showed that ropivacaine produced spinal anesthesia
with similar clinical profile to bupivacaine. In group R the onset of the sensory blockade was slower with a 1.2 times shorter duration and complete motor block
developed rarer than in the group with bupivacaine. The recovery from spinal block was 1.2 times faster, and the time to void was 1.3 times shorter in patients
who had received ropivacaine, compared with patients in group B. The hemodynamic
changes were similar in both groups. In the early postoperative period no patients reported any complaints. In conclusion, isobaric ropivacaine (5 mg/ml) produces equivalent intrathecal anesthesia for inguinal hernia repair and
anorectal surgery with faster recovery compared to bupivacaine. Ropivacaine is
a local anesthetic with good tolerability; provides effective intraoperative analgesia
with minimal motor function suppression and reduced potential for cardioand
CNS-toxicity
Sponge-associated fungi and their bioactive compounds - the Suberites case
No full textSpecimens of Suberites domuncula that had been cultured in aquaria for 4 weeks were analyzed for their associated fungi. A total of 81 fungal strains belonging to 20 different genera was isolated and identified by morphological and molecular methods. The most frequently isolated taxa were Cladosporium spp., Penicillium spp., Petriella sp., Phialophora spp. and Engyodontium album. Based on chromatographic and mass spectrometric analysis of fungal extracts, as well as on bioassay results, Aspergillus ustus, Penicillium sp., Petriella sp. and Scopulariopsis sp. were selected for in-depth analysis of their natural products. A total of 19 different fungal metabolites, including three new natural products, was isolated and structurally identified. A. ustus yielded two sesquiterpenes, a drimane derivative and deoxyuvidin, as well as a sesterterpene ophiobolin H. The drimane derivative had an ED50 value against L5178Y cells of 1.9 mu g ml(-1) in vitro. The crude extract of Petriella sp. was also strongly cytotoxic against the L5178Y cell line. The cyclic tetrapeptide WF-3161 was primarily responsible for the activity; the ED50 value was <0.1 mu g ml(-1). It was identical to the known compound WF-3161 and had been previously isolated from Petriella guttulata. In addition to WF-3161, three further natural products were obtained and unequivocally identified as new derivatives of infectopyrone by one-and two-dimensional NMR spectroscopy and by mass spectroscopy. Of the new compounds, only dihydroinfectopyrone was active against L5178Y cells; the ED50 value was 0.2 mu g ml(-1). Penicillium sp. yielded the largest number of metabolites. Viridicatin, viridicatol, cyclopenin and cyclopenol suppressed larval growth of the polyphagous pest insect Spodoptera littoralis when incorporated into an artificial diet at an arbitrarily chosen concentration of 237 ppm. Viridicatol was the most active compound and had an ED50 value of ca. 50 ppm. Scopulariopsis sp. yielded three metabolites, including the known acetylcholinesterase inhibitors quinolactacin A1 and A2
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