ELECTRONIC PROPERTIES OF THIN FILMS SUBLIMED FROM La@C82 AND Li@C60

V.N. POPOK,A.V. GROMOV,M. JÖNSSON,A. TANINAKA,H. SHINOHARA,E.E.B. CAMPBELL 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2008 NANO Vol.3 No.3

La@C82 and Li@C60 thin films obtained by sublimation in vacuum are studied using four-probe current–voltage measurements and atomic force microscopy. In situ electrical measurements show semiconducting behavior of both films with room-temperature resistivity of 21±8 and 1230±50Ω· cm for the La@C82 and Li@C60, respectively. A variable range hopping mechanism of conductance is suggested from the temperature dependences of resistance. The activation energies for electron transport are calculated for both metallofullerenes. Irreversible changes to the Li@C60 film structure increasing the film resistivity to values typical for C60 are found at elevated temperatures. The effect of exposure to ambient atmosphere on the conductance of the films is discussed.

Isostructural metal-insulator transition in VO₂

Lee, D.,Chung, B.,Shi, Y.,Kim, G.-Y.,Campbell, N.,Xue, F.,Song, K.,Choi, S.-Y.,Podkaminer, J. P.,Kim, T. H.,Ryan, P. J.,Kim, J.-W.,Paudel, T. R.,Kang, J.-H.,Spinuzzi, J. W.,Tenne, D. A.,Tsymbal, E. Y. American Association for the Advancement of Scienc 2018 Science Vol.362 No.6418

<P><B>Separating structure and electrons in VO<SUB>2</SUB></B></P><P>Above 341 kelvin—not far from room temperature—bulk vanadium dioxide (VO<SUB>2</SUB>) is a metal. But as soon as the material is cooled below 341 kelvin, VO<SUB>2</SUB> turns into an insulator and, at the same time, changes its crystal structure from rutile to monoclinic. Lee <I>et al.</I> studied the peculiar behavior of a heterostructure consisting of a layer of VO<SUB>2</SUB> placed underneath a layer of the same material that has a bit less oxygen. In the VO<SUB>2</SUB> layer, the structural transition occurred at a higher temperature than the metal-insulator transition. In between those two temperatures, VO<SUB>2</SUB> was a metal with a monoclinic structure—a combination that does not occur in the absence of the adjoining oxygen-poor layer.</P><P><I>Science</I>, this issue p. 1037</P><P>The metal-insulator transition in correlated materials is usually coupled to a symmetry-lowering structural phase transition. This coupling not only complicates the understanding of the basic mechanism of this phenomenon but also limits the speed and endurance of prospective electronic devices. We demonstrate an isostructural, purely electronically driven metal-insulator transition in epitaxial heterostructures of an archetypal correlated material, vanadium dioxide. A combination of thin-film synthesis, structural and electrical characterizations, and theoretical modeling reveals that an interface interaction suppresses the electronic correlations without changing the crystal structure in this otherwise correlated insulator. This interaction stabilizes a nonequilibrium metallic phase and leads to an isostructural metal-insulator transition. This discovery will provide insights into phase transitions of correlated materials and may aid the design of device functionalities.</P>

AUTOMATED ALIGNMENT IN MULTILINGUAL CORPORA

( J. A. Campbell ),( Alex Chengyu Fang ) 한국언어정보학회 1995 국제 워크샵 Vol.1995 No.-

Experiences in computing alignments at the paragraph and sentence level within a project TRANSLEARN in the European Union``s "LRE" programme of research and development in language engineering are reported. About 98% of the sentences in pairs of corpora in different languages have been aligned correctly by a method that uses dynamic programming on numbers of characters per sentence. This paral-lels the experience of previous researchers for English-French alignment We have used Portuguese and Greek material in addition to these languages. from a set of 49 European Union official documents. It is argued that the key issue of automated alignment is now the automated improvement of the quality of alignment achieved by methods that rely only on character counts. Cues that are helpful to support such an improvement are identified: special words. cognates, syntactic fragments. and a simple measure of seman-tic weight. A short account of their use in experiments is given.

Adsorption Materials and Processes for Carbon Capture from Gas-Fired Power Plants: AMPGas

Gibson, J. A. Arran,Mangano, Enzo,Shiko, Elenica,Greenaway, Alex G.,Gromov, Andrei V.,Lozinska, Magdalena M.,Friedrich, Daniel,Campbell, Eleanor E. B.,Wright, Paul A.,Brandani, Stefano American Chemical Society 2016 INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH - Vol.55 No.13

<P>The key challenge in postcombustion capture from gas-fired power plants is related to the low CO2 concentration in the flue gas (4-8% by volume). This means that conventional amine processes will result in a relatively high energy penalty, whereas novel adsorbents and adsorption processes have the potential to improve the efficiency of separation. High-selectivity adsorbents are required to achieve relatively high CO2 uptake at low partial pressures, which means that the separation process should be based on either very strong physisorption or chemisorption with thermal regeneration. From the process point of view, the main challenge is to develop efficient separation processes with rapid thermal cycles. In this report we present a detailed overview of the methodology behind the development of novel materials and processes as part of the 'Adsorption Materials and Processes for Gas-fired power plants' (AMPGas) project. Examples from a wide variety of materials tested are presented, and the design of an innovative bench-scale 12-column rotary wheel adsorber system is discussed. The strategy to design, characterize, and test novel materials (zeolites, amine-containing MOFs, amine-based silicas, amine-based activated carbons, and carbon nanotubes), specifically designed for CO2 capture from dilute streams is presented.</P>

High temperature superconductor films and devices for the microwave communication industry

N. J. Long,J. Joubert,T. Kemmitt,L. J. Campbell,A. J. Bubendorfer 한국물리학회 2004 Current Applied Physics Vol.4 No.2-4

High temperature superconductor (HTS) thin lms can be used to construct microwave devices such as lters and antennas withsuperior performance. We show how the lms can be manufactured using a solgel method which has the advantage of being able toproduce large area lms quickly, at low cost on simple equipment. We have developed a solgel precursor which has the additionalbenets of using commonly available non-toxic reagents, and which can be prepared quickly. HighTc and high Jc lms have beenmade with this precursor. These lms can be patterned to make microwave lters with better sensitivity and selectivity than con-ventional lters. Adesignfora microstriplayout ofaquasi-elliptic bandpass filter which can be implemented ona10 m×10mm film is described. Simulated results comparing lter implementations with metal and superconductor films operating at 77 K are given.

Wireless operational modal analysis of a multi-span prestressed concrete bridge for structural identification

Matthew J. Whelan,Michael V. Gangone,Kerop D. Janoyan,Neil A. Hoult,Campbell R. Middleton,Kenichi Soga 국제구조공학회 2010 Smart Structures and Systems, An International Jou Vol.6 No.5

Low-power radio frequency (RF) chip transceiver technology and the associated structural health monitoring platforms have matured recently to enable high-rate, lossless transmission of measurement data across large-scale sensor networks. The intrinsic value of these advanced capabilities is the allowance for high-quality, rapid operational modal analysis of in-service structures using distributed accelerometers to experimentally characterize the dynamic response. From the analysis afforded through these dynamic data sets, structural identification techniques can then be utilized to develop a well calibrated finite element (FE) model of the structure for baseline development, extended analytical structural evaluation, and load response assessment. This paper presents a case study in which operational modal analysis is performed on a three-span prestressed reinforced concrete bridge using a wireless sensor network. The low-power wireless platform deployed supported a high-rate, lossless transmission protocol enabling real-time remote acquisition of the vibration response as recorded by twenty-nine accelerometers at a 256 Sps sampling rate. Several instrumentation layouts were utilized to assess the global multi-span response using a stationary sensor array as well as the spatially refined response of a single span using roving sensors and reference-based techniques. Subsequent structural identification using FE modeling and iterative updating through comparison with the experimental analysis is then documented to demonstrate the inherent value in dynamic response measurement across structural systems using high-rate wireless sensor networks.

Wireless operational modal analysis of a multi-span prestressed concrete bridge for structural identification

Whelan, Matthew J.,Gangone, Michael V.,Janoyan, Kerop D.,Hoult, Neil A.,Middleton, Campbell R.,Soga, Kenichi Techno-Press 2010 Smart Structures and Systems, An International Jou Vol.6 No.5

Low-power radio frequency (RF) chip transceiver technology and the associated structural health monitoring platforms have matured recently to enable high-rate, lossless transmission of measurement data across large-scale sensor networks. The intrinsic value of these advanced capabilities is the allowance for high-quality, rapid operational modal analysis of in-service structures using distributed accelerometers to experimentally characterize the dynamic response. From the analysis afforded through these dynamic data sets, structural identification techniques can then be utilized to develop a well calibrated finite element (FE) model of the structure for baseline development, extended analytical structural evaluation, and load response assessment. This paper presents a case study in which operational modal analysis is performed on a three-span prestressed reinforced concrete bridge using a wireless sensor network. The low-power wireless platform deployed supported a high-rate, lossless transmission protocol enabling real-time remote acquisition of the vibration response as recorded by twenty-nine accelerometers at a 256 Sps sampling rate. Several instrumentation layouts were utilized to assess the global multi-span response using a stationary sensor array as well as the spatially refined response of a single span using roving sensors and reference-based techniques. Subsequent structural identification using FE modeling and iterative updating through comparison with the experimental analysis is then documented to demonstrate the inherent value in dynamic response measurement across structural systems using high-rate wireless sensor networks.

Spray-dried plasma attenuates inflammation and improves pregnancy rate of mated female mice

Song, M.,Liu, Y.,Lee, J. J.,Che, T. M.,Soares-Almeida, J. A.,Chun, J. L.,Campbell, J. M.,Polo, J.,Crenshaw, J. D.,Seo, S. W.,Pettigrew, J. E. American Society of Animal Science 2015 Journal of Animal Science Vol. No.

<P>Three studies were conducted to test the hypothesis that dietary spray-dried plasma (SDP) might improve pregnancy rate by ameliorating inflammation, using mice in an experimental model that produces a low pregnancy rate. Mated female mice (C57BL/6 strain) were purchased and shipped from a vendor (Bar Harbor, ME) to the university facility (Urbana, IL) on the day the vaginal plug was found (gestation day [GD] 1), arriving at the laboratory on GD 3 after 2 d transport by air and ground. Mice (Exp. 1: <I>n</I> = 250, 16.0 ± 1.2 g BW; Exp. 2: <I>n</I> = 202, 16.2 ± 1.2 g BW; Exp. 3: <I>n</I> = 156, 16.4 ± 1.1 g BW) were housed in individual cages and randomly assigned to dietary treatments (Exp. 1: 0 [CON] and 8% SDP in the diet, ≥ 90 mice/diet; Exp. 2: 0, 1, 2, 4, and 8% SDP in the diet, ≥ 40 mice/diet; Exp. 3: 0, 1, and 8% SDP in the diet, 48 mice/diet) fed from arrival. In Exp. 1 and 2, pregnancy of each mouse was determined on GD 17 based on BW, shape of abdomen, and inspection postmortem, and maternal growth performance from GD 3 to 17 was measured. On GD 19, pregnant mice in Exp. 2 were euthanized to measure number of fetuses and fetal and placental weights. Pregnancy rates in CON were low in both Exp. 1 (11%) and Exp. 2 (7%). The SDP consistently and markedly increased (<I>P</I> < 0.05) pregnancy rates in both Exp. 1 (49%) and Exp. 2 (35–43%) compared with the CON. In Exp. 3, 12 randomly selected mice were euthanized immediately after they arrived as an initial group. From GD 4 to 7, randomly selected mice were also euthanized each day (12 mice/diet). After euthanasia, the abdominal cavity was opened to check pregnancy by uterine inspection and to collect blood and uterus samples for immune measurements. The SDP increased (<I>P</I> < 0.05; 40 vs. 15%) pregnancy rate compared with the CON. Concentrations of indicators of inflammation and stress (uterine TNF-α and IFN-γ, and serum TNF-α, C-reactive protein, and cortisol) were greatest (<I>P</I> < 0.05) and an anti-inflammatory cytokine (TGF-β1) was lowest (<I>P</I> < 0.05) soon after arrival, on GD 3 or 4. The SDP decreased (<I>P</I> < 0.05) the uterine concentrations of TNF-α and IFN-γ, and serum TNF-α, C-reactive protein, and cortisol, compared with the CON, but increased (<I>P</I> < 0.05) the uterine concentration of TGF-β1. In conclusion, dietary SDP improves the low pregnancy rates in this model, apparently by attenuating inflammation.</P>

Increasing patient-reported allergies are not associated with pain, functional outcomes, or satisfaction following medial patellofemoral ligament reconstruction: a retrospective comparative cohort study

( Andrew S. Bi ),( Dhruv S. Shankar ),( Kinjal D. Vasavada ),( Nina D. Fisher ),( Eric J. Strauss ),( Michael J. Alaia ),( Kirk A. Campbell ) 대한슬관절학회 2022 대한슬관절학회지 Vol.34 No.-

Background: Patient-reported allergies (PRAs) are often stigmatized as a potential nonmodifiable risk factor for increased pain and worse functional outcomes following surgery. However, there is a dearth of literature directly assessing the impact of PRAs on outcomes in sport surgeries such as medial patellofemoral ligament reconstruction (MPFLR). The purpose of our study was to determine whether PRAs were associated with worse outcomes following MPFLR. Methods: We conducted a retrospective review of patients who underwent MPFLR at our institution from 2011 to 2019. Patients were included if they had at least 12 months of follow-up. PRAs were obtained from preoperative medical assessments and categorized by drug class. Demographic and perioperative data were obtained from electronic medical records. Postoperative outcomes were measured using a telephone survey and included recurrent instability, Visual analog scale (VAS) for pain, VAS for sports, Kujala score, MPFL-Return to Sport after Injury (MPFL-RSI) score, and overall satisfaction score. Multiple linear regression was used to determine association between PRAs and outcome measures, and p-values less than 0.05 were considered significant. Results: The cohort included 141 MPFLR. Most patients were female (98, 70%) with an average age of 25 years (range 12-56 years). Average follow-up time was 47 months. Forty-seven patients (33%) reported at least one PRA. There were no significant differences in postoperative pain, functional outcomes, satisfaction, or return to sport between patients with or without PRAs (all p > 0.05). Absence of antibiotic PRAs was predictive of higher VAS (p < 0.007), but there were no other differences. There were no significant differences in outcomes between patients without PRAs, PRAs without a concomitant psychiatric disorder, or PRAs with a concomitant psychiatric disorder (all p > 0.05). Conclusions: In conclusion, PRAs with or without concomitant psychiatric diagnoses are not associated with worse postoperative pain, functional outcomes, or satisfaction following MPFLR with allograft, dispelling common misconceptions that increased number of allergies or psychiatric diagnoses lead to inferior surgical outcomes. Presence of antibiotic allergies was associated with lower VAS postoperative pain score. Future research should investigate the relationship between PRAs and other surgeries in the field of sports medicine.

IMPROVING AUTOMATED ALIGNMENT IN MULTILINGUAL CORPORA

( J. A. Campbell ),( N. Chatterjee ),( Alex Chengyu Fang ),( M. Manela ) 한국언어정보학회 1996 국제 워크샵 Vol.1996 No.-

We report on methods of improving multilingual text alignments that have been produced in a simple dynamic-programming scheme, by automated detec-tion of possible misalignments. Details of methods involving cognates. specially-identified words, and propositional contents of sentences are given, together with notable features of their performance on parallel corpora in a number of different types of European languages.