Pure hydrogen low-temperature plasma exposure of HOPG and graphene: Graphane formation?

Single- and multilayer graphene and highly ordered pyrolytic graphite (HOPG) were exposed to a pure hydrogen low-temperature plasma (LTP). Characterizations include various experimental techniques such as photoelectron spectroscopy, Raman spectroscopy and scanning probe microscopy. Our photoemission measurement shows that hydrogen LTP exposed HOPG has a diamond-like valence-band structure, which suggests double-sided hydrogenation. With the scanning tunneling microscopy technique, various atomic-scale charge-density patterns were observed, which may be associated with different C-H conformers. Hydrogen-LTP-exposed graphene on SiO₂ has a Raman spectrum in which the D peak to G peak ratio is over 4, associated with hydrogenation on both sides. A very low defect density was observed in the scanning probe microscopy measurements, which enables a reverse transformation to graphene. Hydrogen-LTP-exposed HOPG possesses a high thermal stability, and therefore, this transformation requires annealing at over 1000 °C

Interstory drift based scaling of earthquake ground motions

A novel amplitude scaling procedure is proposed in this study where the ground motion scaling factors are defined as the ratio of interstory drift distributions under target spectrum versus under the associated ground motion spectrum. The advantage of employing interstory drift ratio in ground motion scaling, compared to employing spectral intensity directly, is that it provides a strong theoretical link between the target spectrum intensity and the fundamental dynamic characteristics of the structure. Hence, scaling is conditioned on structural response, which is in turn a function of seismic intensity. The interstory drift-based scaling procedure (IDS) is presented herein for planar frames for brevity. Accuracy and efficiency of the IDS procedure is assessed under a set of near fault strong motions from large magnitude events. The results revealed that the proposed procedure is accurate since the resulting bias in estimating linear elastic interstory drifts is negligibly small. Further, it is noticeably more effective as compared to the conventional procedures suggested in recent seismic codes, yet it is simpler

Mass distributions for nuclear disintegration from fission to evaporation

By a proper choice of the excitation energy per nucleon we analyze the mass distributions of the nuclear fragmentation at various excitation energies. Starting from low energies (between 0.1 and 1 MeV/nucleon) up to higher energies about 12 MeV/n, we classified the mass yield characteristics for heavy nuclei (A>200) on the basis of Statistical Multifragmentation Model. The evaluation of fragment distribution with the excitation energy show that the present results exhibit the same trend as the experimental ones.Comment: 5 pages, 3 figure

Robust Syndrome Extraction via BCH Encoding

Quantum data-syndrome (QDS) codes are a class of quantum error-correcting codes that protect against errors both on the data qubits and on the syndrome itself via redundant measurement of stabilizer group elements. One way to define a QDS code is to choose a syndrome measurement code, a classical block code that encodes the syndrome of the underlying quantum code by defining additional stabilizer measurements. We propose the use of primitive narrow-sense BCH codes as syndrome measurement codes. We show that these codes asymptotically require $O(t\log\ell)$ extra measurements, where $\ell$ is the number of stabilizer generators of the quantum code and $t$ is the number of errors corrected by the BCH code. Previously, the best known general method of constructing QDS codes out of quantum codes requires $O(t^3\log\ell)$ extra measurements. As the number of additional syndrome measurements is a reasonable metric for the amount of additional time a general QDS code requires, we conclude that our construction protects against the same number of syndrome errors with significantly less time overhead

Challenges of measuring residual stresses in large girth welded pipe spools by neutron diffraction

In this paper, welding induced residual stresses in a welded API 5L X65 girth pipe spools are discussed in as-welded and in local post weld heat treated conditions. Stress measurements were carried out non-destructively using the neutron diffraction technique. For such large-scale components residual stress measurements require significant preparation and planning. First of all, a choice of stress free lattice spacing value, discussed extensively, is of great importance for the evaluation of residual strains and stresses correctly. Besides, the use of a virtual instrument (SSCANSS software) can optimize measurements for distorted or undistorted large components with or without complex details. Moreover, the well-planned “window” cut through the thickness greatly reduced measurement time. A number of points were measured across the weld, HAZ and the parent material. Measurement results showed that residual stresses in the as-welded condition was lower than the yield strength of the material, and significant relaxation was also observed in the post weld heat treated samples

Treatment of chronic migraine with transcutaneous stimulation of the auricular branch of the vagal nerve (auricular t-VNS):a randomized, monocentric clinical trial

Background Aim of the study was assessment of efficacy and safety of transcutaneous stimulation of the auricular branch of the vagal nerve (t-VNS) in the treatment of chronic migraine. Methods A monocentric, randomized, controlled, double-blind study was conducted. After one month of baseline, chronic migraine patients were randomized to receive 25 Hz or 1 Hz stimulation of the sensory vagal area at the left ear by a handhold battery driven stimulator for 4 h/day during 3 months. Headache days per 28 days were compared between baseline and the last month of treatment and the number of days with acute medication was recorded The Headache Impact Test (HIT-6) and the Migraine Disability Assessment (MIDAS) questionnaires were used to assess headache-related disability. Results Of 46 randomized patients, 40 finished the study (per protocol). In the per protocol analysis, patients in the 1 Hz group had a significantly larger reduction in headache days per 28 days than patients in the 25 Hz group (−7.0 ± 4.6 vs. −3.3 ± 5.4 days, p = 0.035). 29.4 % of the patients in the 1 Hz group had a ≥50 % reduction in headache days vs. 13.3 % in the 25 Hz group. HIT-6 and MIDAS scores were significantly improved in both groups, without group differences. There were no serious treatment-related adverse events. Conclusion Treatment of chronic migraine by t-VNS at 1 Hz was safe and effective. The mean reduction of headache days after 12 weeks of treatment exceeded that reported for other nerve stimulating procedures

Understanding the effects of peripheral vision and muscle memory on in-vehicle touchscreen interactions

It is important to gain a better understanding of how drivers interact with in-vehicle touchscreens to help design interfaces to minimise “eyes off road” time. The study aimed to investigate the relative effects of two interaction mechanisms (peripheral vision - PV and muscle memory - MM) shown to be relevant to visual behaviour when driving, on the time to press different sized buttons (small 6x6cm, medium 10x10cm, large 14x14cm) on an in-vehicle touchscreen. Twenty-five participants took part in a driving simulator study. They were presented with a single, white, square button on the touchscreen on 24 successive trials. For MM conditions, participants wore a pair of glasses that blocked their peripheral vision and for PV conditions they were asked to keep their focus on the vehicle in front throughout. Results showed that task time gradually decreased for the trials when participants could only use MM. However, overall task time for MM conditions were significantly higher than for those in which PV was utilised, and participants rated the use of MM to be more difficult than PV. In contrast, results suggest that for interfaces that utilise peripheral visual processing the learning effect is not evident and operation times are constant over time. These findings indicate that in-vehicle touch screens should be designed to utilise peripheral vision for making simple button selections with reduced visual demand

Understanding the effects of peripheral vision and muscle memory on in-vehicle touchscreen interactions

It is important to gain a better understanding of how drivers interact with in-vehicle touchscreens to help design interfaces to minimise “eyes off road” time. The study aimed to investigate the relative effects of two interaction mechanisms (peripheral vision - PV and muscle memory - MM) shown to be relevant to visual behaviour when driving, on the time to press different sized buttons (small 6x6cm, medium 10x10cm, large 14x14cm) on an in-vehicle touchscreen. Twenty-five participants took part in a driving simulator study. They were presented with a single, white, square button on the touchscreen on 24 successive trials. For MM conditions, participants wore a pair of glasses that blocked their peripheral vision and for PV conditions they were asked to keep their focus on the vehicle in front throughout. Results showed that task time gradually decreased for the trials when participants could only use MM. However, overall task time for MM conditions were significantly higher than for those in which PV was utilised, and participants rated the use of MM to be more difficult than PV. In contrast, results suggest that for interfaces that utilise peripheral visual processing the learning effect is not evident and operation times are constant over time. These findings indicate that in-vehicle touch screens should be designed to utilise peripheral vision for making simple button selections with reduced visual demand

A mutagenicity and cytotoxicity study on Limonium effusum aqueous extracts by Allıum, ames and MTT tests

Nowadays plants or plant extracts have become very important for alternative medicine. Plants and their extracts have many therapeutical advantages but some of them are potentially toxic, mutagenic, carcinogenic and teratogenic. Root, stem and leaf parts of Limonium effusum were used in this study and this species is an endemic species for Turkey. Mutagenic and cytotoxic effects of root, stem and leaf aqueous extracts were observed with Allium, Ames and MTT tests. Allium root growth inhibition test and mitotic index studies showed that aqueous extracts have dose-dependent toxic effects. Chromosome aberration studies indicated that especially sticky chromosome, anaphase-telophase disorder and laggard chromosome anomalies were highly observed. Ames test performed with Limonium effusum root aqueous extracts, showed weak mutagenic effects in Salmonella typhimurium TA98 strain with S9. MTT test based on mitochondrial activity indicated that most of the aqueous extracts have cytotoxic effects. This study aimed to determine the possible mutagenic and cytotoxic effects of L. effusum aqueous extracts by using bacterial, plant and mammalian cells. This research showed that some low concentrations of the L. effusum extracts have inhibited cytotoxic effects but high concentrations have induced cytotoxicity. On the other hand only a weak mutagenic activity was identified by Ames test with TA98 S9(+).В настоящее время растения или экстракты растений стали очень важными для альтернативной медицины. Растения и их экстракты имеют много терапевтических преимуществ, однако некоторые из них являются потенциально токсичными, мутагенными, канцерогенными и тератогенными. Корни, стебли и листья Limonium effusum, эндемичного вида Турции, были изучены в этой работе. Мутагенные и цитотоксические эффекты водных экс-трактов корней, стеблей и листьев Limonium effusum были изучены с помощью Allium-теста, теста Эймса и МТТ-теста. Тест на ингибирование роста корней лука и определение митотического индекса показали, что водные экстракты имеют дозозависимый токсичный эффект. При изучении хромосомных аберраций обнаружено большое количество таких аномалий, как слипшиеся хромосомы, нарушения анафазы-телофазы и отставшие хромосомы. Тест Эймса, проведенный на водных экстрактах корней Limonium effusum, показал слабо выраженный мутагенный эффект по отношению к Salmonella typhimurium, штамм TA98 с S9. МТТ-тест, основанный на митохондриальной активности, показал, что большинство экстрактов имели цитотоксические эффекты. Цель этого исследования изучить возможные мутагенные и цитотоксические эффекты водных экстрактов L. effusum с использованием бактериальных, растительных клеток и клеток млекопитающих. Определенные низкие концентрации экстрактов L. effusum ингибировали цитотоксические эффекты, а высокие концентрации индуцировали цитотоксичность. Слабая мутагенная активность была определена только при помощи теста Эймса с TA98 S9(+)

Assessing the impact of COVID-19 measures on COPD management and patients: A simulation-based decision support tool for COPD services in the UK

© 2022 The Author(s) or their employer(s). Published by BMJ. This is an open access article under the CC BY-NC-ND licence, https://creativecommons.org/licenses/by-nc-nd/4.0/Objectives To develop a computer-based decision support tool (DST) for key decision makers to safely explore the impact on chronic obstructive pulmonary disease (COPD) care of service changes driven by restrictions to prevent the spread of COVID-19.  Design The DST is powered by discrete event simulation which captures the entire patient pathway. To estimate the number of COPD admissions under different scenario settings, a regression model was developed and embedded into the tool. The tool can generate a wide range of patient-related and service-related outputs. Thus, the likely impact of possible changes (eg, COVID-19 restrictions and pandemic scenarios) on patients with COPD and care can be estimated.  Setting COPD services (including outpatient and inpatient departments) at a major provider in central London.  Results Four different scenarios (reflecting the UK government's Plan A, Plan B and Plan C in addition to a benchmark scenario) were run for 1 year. 856, 616 and 484 face-to-face appointments (among 1226 clinic visits) are expected in Plans A, B and C, respectively. Clinic visit quality in Plan A is found to be marginally better than in Plans B and C. Under coronavirus restrictions, lung function tests decreased more than 80% in Plan C as compared with Plan A. Fewer COPD exacerbation-related admissions were seen (284.1 Plan C vs 395.1 in the benchmark) associated with stricter restrictions. Although the results indicate that fewer quality-adjusted life years (in terms of COPD management) would be lost during more severe restrictions, the wider impact on physical and mental health must also be established.  Conclusions This DST will enable COPD services to examine how the latest developments in care delivery and management might impact their service during and beyond the COVID-19 pandemic, and in the event of future pandemics.Peer reviewe