570 research outputs found

    A programmable-load CMOS ring oscillator/inverter chain for propagation-delay measurements

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    A description is given of a test structure consisting of a combination of a ring oscillator and an inverter chain. The circuit can be used to carry out propagation delay measurements on two circuit types and under a number of load conditions. Full characterization only takes one test circuit. The elements of this structure are connected to a programmable load varying from a fan-in of 1 up to a fan-in of 15. In this way, the operating environment of the circuit can be simulated in hardware. The measurements can be carried out by means of a conventional automated digital measurement system providing AC and DC parametric measurement capabilities

    A test chip for automatic reliability measurements of interconnect vias

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    A test circuit for electromigration reliability measurements was designed and tested. The device under test (DUT) is a via-hole chain. The test circuit permits simultaneous measurements of a number of DUTs, and a fatal error of one DUT does not influence the measurement results of the other DUTs. Measurements require only a few measurement instruments. Comparing the measurement results of a single DUT io the measurement results of the test circuit shows that the test circuit may be used for reliability measurements

    Being safe from what and safe for whom? A critical discussion of the conceptual metaphor of ‘safe space’

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    Safe space, used in educational settings as a metaphor, stresses the importance of the classroom being a learning environment characterised by respect and safety. Based on examples from Swedish and Norwegian classroom research, this article problematises and discusses the complexity in the discourse on safe space by asking the critical questions: Being safe from what? – and safe for whom? Related to the concept of safe space are questions about what possibly can make the classroom an unsafe place. In addition to various types of intimidation, harassment and attacks, discussions about certain issues and topics can, for various reasons, be perceived as threatening. The school is part of society, and in an increasingly polarised climate, controversial issues in contemporary society will often be perceived as controversial in classroom practice. In this sense, instead of giving students false promises of being safe in the Religious Education (RE) classroom, the concept ‘classroom of disagreement’ may be a useful metaphor, since it makes it explicitly clear that disagreements exist and are part of life.publishedVersio

    The Biological Standard of Living in the two Germanies.

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    Physical stature is used as a proxy for the biological standard of living in the two Germanies before and after unification in an analysis of a cross-sectional sample (1998) of adult heights, as well as among military recruits of the 1990s. West Germans tended to be taller than East Germans throughout the period under consideration. Contrary to official proclamations of a classless society, there were substantial social differences in physical stature in East-Germany. Social differences in height were greater in the East among females, and less among males than in the West. The difficulties experienced by the East-German population after 1961 is evident in the increase in social inequality of physical stature thereafter, as well as in the increasing gap relative to the height of the West-German population. After unification, however, there is a tendency for East-German males, but not of females, to catch up with their West-German counterparts

    New Particle Formation from the Vapor Phase : From Barrier-Controlled Nucleation to the Collisional Limit

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    Studies of vapor phase nucleation have largely been restricted to one of two limiting cases—nucleation controlled by a substantial free energy barrier or the collisional limit where the barrier is negligible. For weakly bound systems, exploring the transition between these regimes has been an experimental challenge, and how nucleation evolves in this transition remains an open question. We overcome these limitations by combining complementary Laval expansion experiments, providing new particle formation data for carbon dioxide over a uniquely broad range of conditions. Our experimental data together with a kinetic model using rate constants from high-level quantum chemical calculations provide a comprehensive picture of new particle formation as nucleation transitions from a barrier-dominated process to the collisional limit.Peer reviewe

    ESR, raman and conductivity studies on fractionated poly(2-methoxyaniline-5-sulfonic acid)

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    Synthesis methods used to produce poly(2-methoxyaniline-5-sulfonic acid) (PMAS), a water soluble, self-doped conducting polymer, have been shown to form two distinctly different polymer fractions with molecular weights of approximately 2 kDa and 8 -10 kDa. The low molecular weight (LMWT) PMAS fraction is redox inactive and non-conducting while the high molecular weight (HMWT) PMAS is electro-active with electrical conductivities of 0.94 0.05 S cm-1. Previous investigations have illustrated the different photochemical and electrochemical properties of these fractions, but have not correlated these properties with the structural and electronic interactions that drive them. Incomplete purification of the PMAS mixture, typically via bag dialysis, has been shown to result in a mixture of approximately 50:50 HMWT:LMWT PMAS with electrical conductivity significantly lower at approximately 0.10 to 0.26 S cm-1. The difference between the electrical conductivities of these fractions has been investigated by the controlled addition of the non-conducting LMWT PMAS fraction into the HMWT PMAS composite film with the subsequent electronic properties investigated by solid-state ESR and Raman spectroscopies. These studies illustrate strong electronic intereactions of the insulating LMWT PMAS with the emeraldine salt HMWT PMAS to substantially alter the population of the electronic charge carriers in the conducting polymer. ESR studies on these mixtures, when compared to HMWT PMAS, exhibited a lower level of electron spin in the presence of LMWT PMAS indicative of the the formation of low spin bipolarons without a change the oxidation state of the conducting HMWT fraction

    Safety Profile of Upadacitinib up to 3 Years in Psoriatic Arthritis: An Integrated Analysis of Two Pivotal Phase 3 Trials

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    Introduction: This integrated analysis describes the safety profile of upadacitinib, an oral Janus kinase inhibitor, at 15 and 30 mg once daily for up to 3 years of exposure in patients with active psoriatic arthritis (PsA) who had a prior inadequate response or intolerance to ≄ 1 non-biologic or biologic disease-modifying antirheumatic drug. Methods: Safety data were pooled and analyzed from two randomized, placebo-controlled phase 3 trials. Both trials evaluated upadacitinib 15 mg and 30 mg once daily, and one trial also evaluated adalimumab 40 mg every other week. Treatment-emergent adverse events (TEAEs) and laboratory data were summarized for four groups: pooled placebo, pooled upadacitinib 15 mg, pooled upadacitinib 30 mg, and adalimumab. TEAEs were reported as exposure-adjusted event rates (events per 100 patient-years [E/100 PY]) up to a data cut-off of June 29, 2020. Results: A total of 2257 patients received ≄ 1 dose of upadacitinib 15 mg (N = 907) or 30 mg (N = 921) for 2504.6 PY of exposure or adalimumab (N = 429) for 549.7 PY of exposure. Upper respiratory tract infection, nasopharyngitis, and increased creatine phosphokinase (CPK) were the most common TEAEs with upadacitinib. Rates of malignancies, adjudicated major adverse cardiovascular events (MACEs) and venous thromboembolic events (VTEs), and deaths were similar across treatment groups. Rates of herpes zoster (HZ) and opportunistic infections (OI; excluding tuberculosis, HZ, and oral candidiasis) were higher with upadacitinib versus adalimumab. Serious infection, anemia, and CPK elevations were most frequent with upadacitinib 30 mg. Potentially clinically significant laboratory abnormalities were uncommon. Conclusions: Upadacitinib 15 mg and adalimumab had similar safety profiles with the exception of HZ and OIs, consistent with what was observed in rheumatoid arthritis. Rates of malignancies, MACEs, VTEs, and deaths were comparable among patients receiving upadacitinib and adalimumab. No new safety risks emerged with longer-term exposure to upadacitinib. Trial Registration Numbers: SELECT-PsA 1: NCT03104400; SELECT-PsA 2: NCT03104374

    Afferent signalling from the acid-challenged rat stomach is inhibited and gastric acid elimination is enhanced by lafutidine

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    <p>Abstract</p> <p>Background</p> <p>Lafutidine is a histamine H<sub>2 </sub>receptor antagonist, the gastroprotective effect of which is related to its antisecretory activity and its ability to activate a sensory neuron-dependent mechanism of defence. The present study investigated whether intragastric administration of lafutidine (10 and 30 mg/kg) modifies vagal afferent signalling, mucosal injury, intragastric acidity and gastric emptying after gastric acid challenge.</p> <p>Methods</p> <p>Adult rats were treated with vehicle, lafutidine (10 – 30 mg/kg) or cimetidine (10 mg/kg), and 30 min later their stomachs were exposed to exogenous HCl (0.25 M). During the period of 2 h post-HCl, intragastric pH, gastric volume, gastric acidity and extent of macroscopic gastric mucosal injury were determined and the activation of neurons in the brainstem was visualized by c-Fos immunocytochemistry.</p> <p>Results</p> <p>Gastric acid challenge enhanced the expression of c-Fos in the nucleus tractus solitarii but caused only minimal damage to the gastric mucosa. Lafutidine reduced the HCl-evoked expression of c-Fos in the NTS and elevated the intragastric pH following intragastric administration of excess HCl. Further analysis showed that the gastroprotective effect of lafutidine against excess acid was delayed and went in parallel with facilitation of gastric emptying, measured indirectly via gastric volume changes, and a reduction of gastric acidity. The H<sub>2 </sub>receptor antagonist cimetidine had similar but weaker effects.</p> <p>Conclusion</p> <p>These observations indicate that lafutidine inhibits the vagal afferent signalling of a gastric acid insult, which may reflect an inhibitory action on acid-induced gastric pain. The ability of lafutidine to decrease intragastric acidity following exposure to excess HCl cannot be explained by its antisecretory activity but appears to reflect dilution and/or emptying of the acid load into the duodenum. This profile of actions emphasizes the notion that H<sub>2 </sub>receptor antagonists can protect the gastric mucosa from acid injury independently of their ability to suppress gastric acid secretion.</p
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