203 research outputs found
Statistical modeling of leakage currents through SiO2/high- κ dielectrics stacks for non-volatile memory applications
No full textWe present here a statistical Monte Carlo (MC) simulator modeling leakage currents across SiO2/high-kappa dielectric stacks. We show that simulations accurately reproduce experimental currents measured at various temperatures on capacitors with different high-k dielectric stacks. We exploit statistical simulations to investigate the impact of high-kappapsilas traps on leakage current distribution for flash memory applications. We demonstrate that the high defectiveness typical of high-k materials strongly reduces the potential improvement due to the introduction of band-gap engineered high-kappa tunnel dielectric stacks. In this regard, the simulator is a useful tool to optimize high-kappa tunnel stacks and to improve technology reliability issues related to flash memory applications.We present here a statistical Monte Carlo (MC) simulator modeling leakage currents across SiO2/high-κ dielectric stacks. We show that simulations accurately reproduce experimental currents measured at various temperatures on capacitors with different high-k dielectric stacks. We exploit statistical simulations to investigate the impact of high-κ's traps on leakage current distribution for Flash memory applications. We demonstrate that the high defectiveness typical of high-k materials strongly reduces the potential improvement due to the introduction of band-gap engineered high-κ tunnel dielectric stacks. In this regard, the simulator is a useful tool to optimize high-κ tunnel stacks and to improve technology- reliability issues related to Flash memory applications. © 2008 IEEE
Unmet therapeutic, educational and scientific needs in parathyroid disorders : consensus statement from the first European Society of Endocrinology Workshop (PARAT)
No full textAbstract: PARAT, a new European Society of Endocrinology program, aims to identify unmet scientific and educational needs of parathyroid disorders, such as primary hyperparathyroidism (PHPT), including parathyroid cancer (PC), and hypoparathyroidism (HypoPT). The discussions and consensus statements from the first PARAT workshop (September 2018) are reviewed. PHPT has a high prevalence in Western communities, yet evidence is sparse concerning the natural history and whether morbidity and long-term outcomes are related to hypercalcemia or plasma PTH concentrations or both. Cardiovascular mortality and prevalence of low energy fractures are increased, whereas quality of life is decreased, although their reversibility by treatment of PHPT has not been convincingly demonstrated. PC is a rare cause of PHPT, with increasing incidence, and international collaborative studies are required to advance knowledge of the genetic mechanisms, biomarkers for disease activity and optimal treatments. For example, similar to 20% of PCs demonstrate high mutational burden, and identifying targetable DNA variations, gene amplifications and gene fusions may facilitate personalized care, such as different forms of immunotherapy or targeted therapy. HypoPT, a designated orphan disease, is associated with a high risk of symptoms and complications. Most cases are secondary to neck surgery. However, there is a need to better understand the relation between disease biomarkers and intellectual function and to establish the role of PTH in target tissues, as these may facilitate the appropriate use of PTH substitution therapy. Management of parathyroid disorders is challenging, and PARAT has highlighted the need for international transdisciplinary scientific and educational studies in advancing in this field
Feasibility of SIO2/Al2O3 tunnel dielectric for future Flash memories generations
No full textIn this paper, we investigate the feasibility of SiO2/Al2O3 stack tunnel dielectric for future Flash memory generations using statistical leakage current simulations. We show that the statistical Monte Carlo (MC) simulator we employed reproduces accurately leakage currents measured on SiO2/Al2O3 dielectric capacitors. Exploiting its statistical capabilities, we calculate leakage current distributions in Flash memory retention conditions. We show that the high defectiveness of AI2O3 stacks strongly reduces the potential improvement of Flash retention due to the introduction of AI2O3 tunnel dielectric
Morphine alters the circulating proteolytic profile in mice: functional consequences on cellular migration and invasion
No full textOpioids modulate the tumor microenvironment with potential functional consequences for tumor growth and metastasis. We evaluated the effects of morphine administration on the circulating proteolytic profile of tumor-free mice. Serum from morphine-treated (1 or 10 mg/kg, i.p. every 12 h) or saline-treated mice was collected at different time points and tested ex vivo in endothelial, lymphatic endothelial, and breast cancer cell migration assays. Serum from mice that were treated with 10 mg/kg morphine for 3 d displayed reduced chemotactic potential for endothelial and breast cancer cells, and elicited reduced cancer cell invasion through reconstituted basement membrane compared with serum from saline controls. This was associated with decreased circulating matrix metalloproteinase 9 (MMP-9) and increased circulating tissue inhibitor of metalloproteinase 1 (TIMP-1) and TIMP-3/4 as assessed by zymography and reverse zymography. By using quantitative RT-PCR, we confirmed morphine-induced alterations in MMP-9 and TIMP expression and identified organs, including the liver and spleen, in which these changes originated. Pharmacologic inhibition of MMP-9 abrogated the difference in chemotactic attraction between serum from saline-treated and morphine-treated mice, which indicated that reduced proteolytic ability mediated the decreased migration toward serum from morphine-treated mice. This novel mechanism may enable morphine administration to promote an environment that is less conducive to tumor growth, invasion, and metastasis.-Xie, N., Khabbazi, S., Nassar, Z. D., Gregory, K., Vithanage, T., Anand-Apte, B., Cabot, P. J., Sturgess, D., Shaw, P. N., Parat, M.-O. Morphine alters the circulating proteolytic profile in mice: functional consequences on cellular migration and invasion
European Expert Consensus on Practical Management of Specific Aspects of Parathyroid Disorders in Adults and in Pregnancy:Recommendations of the ESE Educational Program of Parathyroid Disorders
No full textThis European expert consensus statement provides recommendations for the diagnosis and management of primary hyperparathyroidism (PHPT), chronic hypoparathyroidism in adults (HypoPT), and parathyroid disorders in relation to pregnancy and lactation. Specified areas of interest and unmet needs identified by experts at the second ESE Educational Program of Parathyroid Disorders (PARAT) in 2019, were discussed during two virtual workshops in 2021, and subsequently developed by working groups with interest in the specified areas. PHPT is a common endocrine disease. However, its differential diagnosing to familial hypocalciuric hypercalcemia (FHH), the definition and clinical course of normocalcemic PHPT, and the optimal management of its recurrence after surgery represent areas of uncertainty requiring clarifications. HypoPT is an orphan disease characterized by low calcium concentrations due to insufficient PTH secretion, most often secondary to neck surgery. Prevention and prediction of surgical injury to the parathyroid glands are essential to limit the disease-related burden. Long-term treatment modalities including the place for PTH replacement therapy and the optimal biochemical monitoring and imaging surveillance for complications to treatment in chronic HypoPT, need to be refined. The physiological changes in calcium metabolism occurring during pregnancy and lactation modify the clinical presentation and management of parathyroid disorders in these periods of life. Modern interdisciplinary approaches to PHPT and HypoPT in pregnant and lactating women and their newborns children are proposed. The recommendations on clinical management presented here will serve as background for further educational material aimed for a broader clinical audience, and were developed with focus on endocrinologists in training
Computer-generierte Parallel-Tests für die Fähigkeitsmessung in der Eignungsauswahl von operationellem Luftfahrtpersonal
No full textIn den Personalauswahlprogrammen großer Luftfahrtunternehmen wird die psychologische Eignungsmessung zunehmend durch externe Testvorbereitung oder Wiederholungsuntersuchungen erschwert. Um trotzdem standardisierte Leistungsmessungen zu ermöglichen, wurde das Programm PARAT 2000 konzipiert. Die in diesem Programm entwickelten Tests sollten folgenden Bedingungen genügen: 1. Systematische Vorinformation mit Übungsaufgaben, damit die Vorkenntnisse nivelliert werden; 2. Möglichkeit zur Computer-Generierung beliebig vieler Paralleltests, damit immer wieder neue Itemsets eingesetzt werden können; 3. Kultur-Fairneß, damit internationale Bewerbergruppen untersucht werden können. Dieser Bericht beschreibt die bisher erprobten PARAT-Tests für die Merkmale Logisches Denken, Gedächtnis (kurzzeitig und assoziativ), Aufmerksamkeit und Raumvorstellung (Orientierung und Visualisierung). Dazu werden Aufgabenbeispiele und psychometrische Eigenschaften mitgeteilt
Seditio & στάσις: Tacitus and Cassius Dio on the revolt of the Pannonian legions in AD 14
No full textMeđu grčko-rimskim autorima koji su ostavili pisani trag o pobuni panonskih legija g. 14. najpodrobniji su Tacit i Kasije Dion. Umnogome različita, dva vrela upućuju na slična pitanja što proizlaze iz ove epizode. Relevantni ulomci stavljaju se u kontekst dviju monografija kojima pripadaju. Traže se moguće podudarnosti i razlike. Ispituje se što se iz njih može doznati o vojno-političkim pogledima dvojice pisaca. Pokušava se razaznati utjecaj ranije historiografije i je li mlađi autor preuzimao građu od starijegSeveral ancient writers mentioned the revolt of the Pannonian legions that broke out almost immediately upon Augustus' death in AD 14. The evidence is best attested in Tacitus' Annals and, to some extant, in Dio's Roman History. Placed whithin the broader context of Tiberius' ascension to the imperial throne, the two narratives vividly depict army's mutinous acts. This paper relies on Tacitus' and Dio's data and discusses the similarities or differences between the two sources. More precisely, it examines the way in which their own thoughts influenced the accounts on the Pannoninan revolt. The purpose is to sketch out a coherent picture of what shaped the data attested in Tacitus' and Dio's writings.
Unusually extended and elaborated, Tacitus' account implies that both earlier authors and his previous works left a strong mark on his views on the military disobedience. Despite the pessimistic tone, there is no reason to assume that Tacitus questioned the very foundations of the Principate nor that he accused troops for such deeds. On the other hand, Dio's condensed chapter seemingly fails to offer additional informaton. However, the Greek author provides a number of comparative examples elsewhere in the Roman history. If carefully scritinized, they show that Dio's views were shaped by his personal experience and by contemporary Greek culture. Even in this short paragraph one can discern following features: Dio avoids details, but preferes accuracy; he is ironic, but well-aware of the threat of military unrest; he offers no comment, but infers conclusions. The similarities between the two narratives are insufficient to assess that Dio relied mainly on Tacitus' data. It seems that the two authors drew from a variety of sources, and that at least some of them were known exclusively to Dio
Can inter-firm networks alleviate supply chain risks within global food supply chains?
No full textThe food supply chain is truly a global supply chain wherein finished products and raw materials are transported across continents to fulfil requirements of consumers. The networks of supply encompass different languages, cultural systems, regulations etc. The entire farmer to end user cycle spans multiple risks and uncertainties which can manifest themselves in form of financial losses to human fatalities. In the past there have been instances of product recalls and food contamination which have had serious consequences as witnessed by the China milk scare, the Sudan1 dye in Worcester sauce and the Tomato salsa recall amongst others. This paper presents a literature study of the issues surrounding these complex and multi-tiered supply chain structures. It also presents a secondary analysis of the literature pertaining to supply chain risks in the food sector. Inter-firm aspects specifically in terms of relationships, trust and governance are analysed and a conceptual model for mitigating risk is derived
Characterization and origin of alcaline magmas and fluids beneath the Jbel Saghro volcanic field, Anti Atlas, Morocco
No full textLes laves alcalines sous-saturées riches en éléments volatils sont les marqueurs du rôle important des fluides dans le manteau et des interactions fluide-roche et magma-roche, processus clés pour comprendre la dynamique du manteau convectif et les interactions asthénosphère-lithosphère en domaine intracontinental. L’objectif de cette thèse est d’apporter de nouvelles contraintes sur la genèse des magmas alcalins en caractérisant les conditions de cristallisation, la source et les processus de fusion partielle à l’origine des néphélinites à olivine, des néphélinites à pyroxène et des basanites du champ volcanique du Jbel Saghro dans l’Anti-Atlas marocain. L’étude pétrologique et géochimique des roches et des minéraux, couplée à l’analyse des inclusions fluides a permis de contraindre les conditions pré-éruptives des néphélinites de Saghro à 1.7–2.2 GPa et ~1350 °C. Les minéraux montrent que les magmas néphélinitiques sont riches en éléments volatils (Cl, F, S), et les inclusions fluides indiquent que les magmas étaient saturés en fluide riche en CO2 à des pressions > 590 MPa. Les différents assemblages minéralogiques des néphélinites et la présence de xénolites péridotitiques suggèrent une ascension rapide des néphélinites à olivine et des processus plus complexes en profondeur pour les néphélinites à pyroxène. La modélisation des processus de cristallisation fractionnée et de fusion partielle des laves mafiques de Saghro a permis de déterminer qu’elles sont issues de faibles taux de fusion partielle (0.6–2.5 %) d’une péridotite carbonatée enrichie en éléments incompatibles, au niveau de la transition grenat–spinelle (~80–85 km) et en présence d’amphibole. Les néphélinites de Saghro montrent une évolution temporelle avec une légère augmentation du taux de fusion et une diminution de la quantité d’amphibole au résidu des plus anciennes (néphélinites à olivine, 9.6 Ma) aux plus récentes (néphélinites à pyroxène, 2.9 Ma). Les basanites forment un système indépendant des néphélinites et sont issues de taux de fusion plus élevés. Les fortes variations dans leur composition chimique suggèrent qu’elles ont subi de la cristallisation fractionnée lors de leur ascension. Les caractéristiques particulières des néphélinites et basanites de Saghro (enrichissement en éléments incompatibles, anomalies négatives en K, Zr, Hf et Ti, rapports Ca/Al et Zr/Hf élevés) indiquent que leur source a subi un métasomatisme principalement carbonatitique. L’influence de ce métasomatisme est plus forte pour les néphélinites à pyroxène que pour les néphélinites à olivine, impliquant une évolution temporelle de l’intensité du métasomatisme. Ces résultats suggèrent des interactions fluide-roche sous le craton Nord-Ouest Africain, entraînant la formation d'un manteau métasomatisé par des composants carbonatitiques riches en CO2 au niveau de la transition lithosphère-asthénosphère. L’origine du métasomatisme provoquant l’enrichissement de la source et la formation de veines d’amphibole pourrait être liée à la fusion de reliquats de croûte océanique subductée. Les températures de fusion relativement faibles ( 590 MPa. The various mineralogical assemblages and the presence of peridotite xenoliths suggest a rapid ascent for olivine nephelinites and more complex processes at depth for pyroxene nephelinites. Fractional crystallization and partial melting modelling of Saghro mafic lavas indicate that they are low-degree melts (0.6–2.5 %) of an amphibole-bearing carbonated peridotite enriched in incompatible elements, at the garnet-spinel transition (~80–85 km). Saghro nephelinites display a temporal evolution with a slight increase of the degree of melting and a decrease of the amount of residual amphibole from the oldest (olivine nephelinites, 9.6 Ma) to the most recent (pyroxene nephelinites, 2.9 Ma). Basanites form a system that is independent from nephelinites and are slightly higher-degree melts. Important variations in their chemical composition suggest variable amounts of fractional crystallization during ascent. The peculiar characteristics of Saghro nephelinites and basanites (enrichment in incompatible elements, negative anomalies in K, Zr, Hf and Ti, high Ca/Al and Zr/Hf ratios) indicate that their source was affected by carbonatitic metasomatism. The influence of this metasomatism is stronger for pyroxene nephelinites than for olivine nephelinites. These results suggest fluid-rock interactions beneath the Northwest African Craton, leading to the formation of a metasomatized mantle by CO2-rich carbonatitic components at the lithosphere-asthenosphere transition. The origin of the metasomatism inducing source enrichment and the formation of amphibole veins could be attributed to the melting of relict subducted oce anic lithosphere. The relatively low melting temperatures (< 1350 °C) suggest the absence of a thermal anomaly beneath the Jbel Saghro, and thus support a lithosphere delamination model as precursor of Saghro volca0,3nism. However, the increasing degree of partial melting over time, also observed in the Middle Atlas, together with the isotopic and geochemical similarities with Canary Islands alkaline lavas does not allow us to discard the influence of a deviation of the Canary mantle plume beneath northwest Africa
Role of volatiles (S, Cl, H2O) and silica activity on the crystallization of hauyne and nosean in phonolitic magmas (Eifel, Germany and Saghro, Morocco)
No full textInternational audienceTo constrain the crystallization of alkaline and volatile-rich lavas present in intraplate settings, we studied the petrological features and the geochemical composition of major, trace, and volatile elements of mineral and bulk-rock of two sodalite-bearing phonolites: (1) haüyne-plagioclase-bearing Si-K-rich phonolite from Laacher See (Germany) and (2) nosean-nepheline-bearing Si-poor phonolite from Saghro (Morocco). In haüyne-bearing phonolites (55–59 wt% SiO2, K > Na, Na+K/Al = 0.96–1.08), we found that the low silica and low sodium activity promoted the early crystallization of S-rich haüyne (13.7–13.9 wt% SO3, 0.4 wt% Cl) + S-rich apatite (0.7–0.9 wt% SO3), titanite, and rare pyrrhotite followed by clinopyroxene-plagioclase-sanidine at relatively low pressure and temperature (P = 250 MPa and T = 850 °C) and oxidized condition (ΔNNO-NNO+1, where NNO is nickel-nickel oxide buffer). The crystallization of haüyne occurred at fluid-undersaturated conditions from a silicate melt with 6 wt% H2O, 0.17–0.23 wt% Cl, 0.11–0.4 wt% S, and 0.07–0.14 wt% F. Nosean-bearing phonolites from Saghro are silica-poor and peralkaline (52–54 wt% SiO2, Na > K, Na+K/Al = 1.2) and crystallized at higher P and T (300 MPa and 950 °C) and more reduced conditions (NNO) compared to haüyne-bearing phonolites. The incongruent reaction to form nosean requires high silica and Na2O activity. The mineral assemblage and composition suggest early crystallization of nepheline followed by nosean (7.8–8.8 wt% SO3; 1–1.1 wt% Cl). The sequence of crystallization is: clinopyroxene + nepheline + S-poor apatite (<0.04 wt% SO3) + pyrrhotite followed by nosean and titanite. Nosean-bearing magmas are fluid-undersaturated with relatively low volatile content (4 wt% H2O, <0.25 wt% Cl, <0.056 wt% S, 0.08–0.1 wt% F), although Cl may have exsolved during ascent and formed a fluid phase (NaCl-bearing).Both haüyne- and nosean-bearing phonolites are last equilibrated at relatively low pressure and high temperature. Haüyne and nosean crystallized at oxidized and volatile-rich pre-eruptive conditions. They record the volatile concentrations at depth and may be used as oxybarometer. The incongruent reactions involved to form haüyne and nosean suggest that phonolitic magmas became more oxidized during crystallization. The initial volatile concentrations in basanite/nephelinite magmas, from partial melting of volatile-bearing K2O-rich mantle rock, should have been one important factor influencing the crystallization of haüyne-bearing Si-K-rich phonolite and nosean-bearing Si-poor phonolite in intracontinental setting
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