122 results on '"Brown, GJ"'
Search Results
2. COMPUTATIONAL AUDITORY SCENE ANALYSIS: GROUPING SOUND SOURCES USING COMMON PITCH CONTOURS
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BROWN, GJ, primary and COOKE, MP, additional
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- 2024
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3. THE PERCEPTION OF PROSODY: A MULTI-SCALE AUDITORY MODEL
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MCANGUS TODD, NP, primary and BROWN, GJ, additional
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- 2024
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4. DESIGN COLLECTION AND ANALYSIS OF A MULTI-SIMULTANEOUS-SPEAKER CORPUS
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CRAWFORD, M, primary, BROWN, GJ, additional, COOKE, M, additional, and GREEN, P, additional
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- 2024
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5. COMPUTATIONAL AUDITORY SCENE ANALYSIS: MODELLING THE COMPETITION BETWEEN ALTERNATIVE PERCEPTUAL ORGANISATIONS
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GODSMARK, DJ, primary and BROWN, GJ, additional
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- 2024
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6. PATTERNS OF CONFUSION MADE BY A MODEL OF DOUBLE-VOWEL IDENTIFICATION: A COMPARISON WITH HUMAN DATA
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MAKIN, SJ, primary and BROWN, GJ, additional
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- 2024
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7. TLR7 gain-of-function genetic variation causes human lupus
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Brown, GJ, Canete, PF, Wang, H, Medhavy, A, Bones, J, Roco, JA, He, Y, Qin, Y, Cappello, J, Ellyard, JI, Bassett, K, Shen, Q, Burgio, G, Zhang, Y, Turnbull, C, Meng, X, Wu, P, Cho, E, Miosge, LA, Andrews, TD, Field, MA, Tvorogov, D, Lopez, AF, Babon, JJ, Lopez, CA, Gonzalez-Murillo, A, Garulo, DC, Pascual, V, Levy, T, Mallack, EJ, Calame, DG, Lotze, T, Lupski, JR, Ding, H, Ullah, TR, Walters, GD, Koina, ME, Cook, MC, Shen, N, de Lucas Collantes, C, Corry, B, Gantier, MP, Athanasopoulos, V, Vinuesa, CG, Brown, GJ, Canete, PF, Wang, H, Medhavy, A, Bones, J, Roco, JA, He, Y, Qin, Y, Cappello, J, Ellyard, JI, Bassett, K, Shen, Q, Burgio, G, Zhang, Y, Turnbull, C, Meng, X, Wu, P, Cho, E, Miosge, LA, Andrews, TD, Field, MA, Tvorogov, D, Lopez, AF, Babon, JJ, Lopez, CA, Gonzalez-Murillo, A, Garulo, DC, Pascual, V, Levy, T, Mallack, EJ, Calame, DG, Lotze, T, Lupski, JR, Ding, H, Ullah, TR, Walters, GD, Koina, ME, Cook, MC, Shen, N, de Lucas Collantes, C, Corry, B, Gantier, MP, Athanasopoulos, V, and Vinuesa, CG
- Abstract
Although circumstantial evidence supports enhanced Toll-like receptor 7 (TLR7) signalling as a mechanism of human systemic autoimmune disease1-7, evidence of lupus-causing TLR7 gene variants is lacking. Here we describe human systemic lupus erythematosus caused by a TLR7 gain-of-function variant. TLR7 is a sensor of viral RNA8,9 and binds to guanosine10-12. We identified a de novo, previously undescribed missense TLR7Y264H variant in a child with severe lupus and additional variants in other patients with lupus. The TLR7Y264H variant selectively increased sensing of guanosine and 2',3'-cGMP10-12, and was sufficient to cause lupus when introduced into mice. We show that enhanced TLR7 signalling drives aberrant survival of B cell receptor (BCR)-activated B cells, and in a cell-intrinsic manner, accumulation of CD11c+ age-associated B cells and germinal centre B cells. Follicular and extrafollicular helper T cells were also increased but these phenotypes were cell-extrinsic. Deficiency of MyD88 (an adaptor protein downstream of TLR7) rescued autoimmunity, aberrant B cell survival, and all cellular and serological phenotypes. Despite prominent spontaneous germinal-centre formation in Tlr7Y264H mice, autoimmunity was not ameliorated by germinal-centre deficiency, suggesting an extrafollicular origin of pathogenic B cells. We establish the importance of TLR7 and guanosine-containing self-ligands for human lupus pathogenesis, which paves the way for therapeutic TLR7 or MyD88 inhibition.
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- 2022
8. A comparison of calcium and phosphorus in components of fertile and size-matched unbanded Nile crocodile eggs
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Brown, GJ, primary, Forbes, PBC, additional, Myburgh, JG, additional, and Nöthling, JO, additional
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- 2021
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9. COLD SNARE POLYPECTOMY OF COLORECTAL POLYPS ≤10MM ON CLOPIDOGREL: AN AUSTRALIAN AND NEW ZEALAND RANDOMISED CONTROLLED TRIAL
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Ket, SN, Hewett, DG, Kheir, AO, Metz, AJ, Moss, A, Ogra, R, Tjandra, DP, Tam, W, Secomb, R, Raftopoulos, S, Cavalieri, L, Urquhart, P, Brown, GJ, Ket, SN, Hewett, DG, Kheir, AO, Metz, AJ, Moss, A, Ogra, R, Tjandra, DP, Tam, W, Secomb, R, Raftopoulos, S, Cavalieri, L, Urquhart, P, and Brown, GJ
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Background and study aims Optimal peri-colonoscopic management of clopidogrel remains unclear. Cold snare polypectomy is safe and effective for removing polyps ≤ 10 mm and clips can control intraprocedural bleeding. We conducted a randomized controlled trial to compare continuation of clopidogrel versus temporary replacement of clopidogrel with aspirin for routine colonoscopy using cold snare polypectomy for polyps ≤ 10 mm. Patients and methods Between August 2016 and August 2019, consenting participants at 12 centers were randomized to continuation of clopidogrel as a single or dual antiplatelet agent, or to temporarily take aspirin alone from 7 days prior to 2 days after routine colonoscopy. Endoscopists were blinded to group allocation. Cold snare polypectomy was used to remove polyps ≤ 10 mm, with endoscopic clips applied if intraprocedural bleeding continued for > 2 minutes. Follow-up was performed on Day 30. The trial was stopped early due to delayed patient enrollment. Results Two hundred seventy-six consecutive polyps ≤ 10 mm were removed from 107 patients. Of the patients, 61.7 % were male with a median age of 69 years (interquartile range [IQR] 63 to 76.75). Fifty-nine patients continued on clopidogrel and 48 temporarily took aspirin instead. One hundred thirty-four polyps were removed from 49 patients who continued on clopidogrel vs 142 from 43 patients temporarily took aspirin instead (P = 0.33). Intraprocedural bleeding requiring clips occurred in 11 of 49 patients who continued on clopidogrel and in two of 43 patients who temporarily took replacing with aspirin instead (P = 0.02). More post-procedural minor bleeding was seen in the aspirin arm (six of 43 vs one of 49; P = 0.03). One patient in each arm had acute coronary syndrome, which was medically managed. None of the patients had clinically significant post-procedural bleeding. Conclusions Continuation of clopidogrel in patients undergoing cold snare polypectomy for colorectal polyps ≤
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- 2020
10. Clinical coding data algorithm to categorize type of gastrointestinal bleeding as a primary reason for massive transfusion: results from the Australian and New Zealand Massive Transfusion Registry
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Ket, SN, Sparrow, RL, McQuilten, ZK, Tacey, M, Gibson, PR, Brown, GJ, Wood, EM, Ket, SN, Sparrow, RL, McQuilten, ZK, Tacey, M, Gibson, PR, Brown, GJ, and Wood, EM
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BACKGROUND: Management of major gastrointestinal bleeding (GIB) may require massive transfusion (MT), but limited data are available. Upper and lower GIB have different aetiologies, prognosis, bleeding patterns and outcomes. Better understanding of current transfusion management and outcomes in these patients is important. We sought to define and validate an algorithm based on clinical coding data to distinguish critical upper and lower GIB using data from the Australian and New Zealand Massive Transfusion Registry (ANZ-MTR). STUDY DESIGN AND METHODS: Australian and New Zealand Massive Transfusion Registry hospital-source data on adult patients receiving a MT (defined as ≥5 red cell units within 4 h) for any bleeding context were used. An algorithm allocating ICD-10-AM codes into 'probable' or 'possible' causes of GIB was developed and applied to the ANZ-MTR. Source medical records of 69 randomly selected cases were independently reviewed to validate the algorithm. RESULTS: Of 5482 MT cases available from 25 hospitals, 716 (13%) were identified as GIB with 538/716 (75%) categorized 'probable' and 178/716 'possible' GIB. Upper and lower GIB causes of MT were identified for 455/538 (85%) and 76/538 (14%) 'probable' cases, respectively; 7/538 (1·3%) cases had both upper and lower GIB. Allocation by the algorithm into a 'probable' GIB category had a 95·7% (CI: 90-100%) positive predictive value when validated against source medical records. CONCLUSION: An algorithm based on ICD-10-AM codes can be used to accurately categorize patients with luminal GIB as the primary reason for MT, enabling further study of this critically unwell and resource-intensive cohort of patients.
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- 2019
11. Quantum cascade laser stabilization at sub-Hz-level by use of a frequency comb and an optical link
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Argence, Bérengère, Chanteau, Bruno, Lopez, Olivier, Nicolodi, Daniele, Abgrall, Michel, Chardonnet, Christian, Daussy, Christophe, Darquié, Benoît, Le Coq, Yann, Amy-Klein, Anne, Tournie, E., Brown, Gj, Systèmes de Référence Temps Espace (SYRTE), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), Métrologie des fréquences optiques, Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), and Références micro-ondes et échelles de temps
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Optical fiber ,Materials science ,business.industry ,Optical link ,Laser ,Spectral line ,law.invention ,Metrology ,Frequency comb ,Optics ,law ,Cascade ,Optoelectronics ,[PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph] ,business ,Quantum cascade laser - Abstract
With their large mid-infrared spectral coverage, Quantum Cascade Lasers (QCL) are very promising for probing the molecular fingerprint region. Current applications to high-resolution spectroscopy are mainly limited by their large freerunning frequency instability. A lot of efforts have thus been made recently to characterize and improve their spectral properties, especially the emission line width and the traceability to frequency standards. Here we demonstrate the frequency stabilization of a QCL emitting at 10 μm onto an optical frequency comb (OFC), itself controlled with a remote near-infrared ultra-stable laser. The latter frequency is transferred with an optical fiber link of 43 km from a metrological institute, where its frequency is monitored against frequency standards. From the reference ultra-stable laser stability, one can infer a QCL line width below 1 Hz and a relative frequency stability of 2x10 -15 for an averaging time of 1 s. Moreover the QCL frequency is known with an uncertainty of at most 10 -14 after 100 s averaging time, thanks to the traceability to primary standards. This performance overcome by at least two orders of magnitude what has been demonstrated up to now with a QCL. We further demonstrate the continuous tuning of this stabilized QCL and recorded a few OsO4 molecular absorption lines, some of them being unreported so far to our knowledge. The saturated absorption line width is 25 kHz, well below what has ever been recorded with a QCL. These results open the way to ultra-high precision measurements with molecules with the same performance than currently achieved with atoms.
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- 2015
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12. Cost Analysis of Endoscopic Mucosal Resection vs Surgery for Large Laterally Spreading Colorectal Lesions
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Jayanna, M, Burgess, NG, Singh, R, Hourigan, LF, Brown, GJ, Zanati, SA, Moss, A, Lim, J, Sonson, R, Williams, SJ, Bourke, MJ, Jayanna, M, Burgess, NG, Singh, R, Hourigan, LF, Brown, GJ, Zanati, SA, Moss, A, Lim, J, Sonson, R, Williams, SJ, and Bourke, MJ
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BACKGROUND & AIMS: Large laterally spreading lesions (LSL) in the colon and rectum can be safely and effectively removed by endoscopic mucosal resection (EMR). However, many patients still undergo surgery. Endoscopic treatment may be more cost effective. We compared the costs of endoscopic versus surgical management of large LSL. METHODS: We performed a prospective, observational, multicenter study of consecutive patients referred to 1 of 7 academic hospitals in Australia for the management of large LSL (≥ 20 mm) from January 2010 to December 2013. We collected data on numbers of patients undergoing EMR, actual endoscopic management costs (index colonoscopy, hospital stay, adverse events, and first surveillance colonoscopy), characteristics of patients and lesions, outcomes, and adverse events, and findings from follow-up examinations 14 days, 4-6 months, and 16-18 months after treatment. We compared data from patients who underwent EMR with those from a model in which all patients underwent surgery without any complications. Event-specific costs, based on Australian refined diagnosis-related group codes, were used to estimate average cost per patient. RESULTS: EMR was performed on 1489 lesions (mean size, 36 mm) in 1353 patients (mean age, 67 years; 52.1% male). Total costs involved in the endoscopic management of large LSL were US $6,316,593 and total inpatient hospitalization length of stay was 1180 days. The total cost predicted for the surgical management group was US $16,601,502, with a total inpatient hospitalization length of stay of 4986 days. Endoscopic management produced a potential total cost saving of US $10,284,909; the mean cost difference per patient was US $7602 (95% confidence interval, $8458-$9220; P < .001). Inpatient hospitalization length of stay was reduced by 2.81 nights per patient (95% confidence interval, 2.69-2.94; P < .001). CONCLUSIONS: In a large multicenter study, endoscopic management of large LSL by EMR was significantly more cost
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- 2016
13. Capsule endoscopy versus magnetic resonance enterography for the detection of small bowel polyps in Peutz-Jeghers syndrome
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Urquhart, P, Grimpen, F, Lim, GJ, Pizzey, C, Stella, DL, Tesar, PA, Macrae, FA, Appleyard, MA, Brown, GJ, Urquhart, P, Grimpen, F, Lim, GJ, Pizzey, C, Stella, DL, Tesar, PA, Macrae, FA, Appleyard, MA, and Brown, GJ
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Our study aimed to assess the diagnostic utility of magnetic resonance enterography (MRE) compared to capsule endoscopy (CE) for the detection of small bowel polyps in patients with Peutz-Jeghers syndrome (PJS); with findings verified by balloon enteroscopy (BE). Adult patients were prospectively recruited across two tertiary centres and underwent MRE followed by CE, with a subsequent BE performed in patients with significant (≥10 mm) polyps. The primary endpoint was the total number of significant (≥10 mm) small bowel polyps detected. The number of patients with at least one significant polyp, correlation with BE findings, and patients' preferences were secondary endpoints. A total of 20 patients (7 male; mean age 34.9 years) underwent both investigations. The number of polyps ≥10 mm detected by CE was greater than by MRE (47 vs 14 polyps, P = 0.02). The number of patients with at least one significant polyp identified by CE was 11 (55 %) compared with 7 (35 %) identified by MRE (P = 0.25). Subsequent BE in 12 patients identified a total of 26 significant polyps in 8 patients. The positive predictive value of finding a polyp at BE was higher for MRE (100 %) compared to CE (60 %). Overall patient preferences identified CE as the preferred modality. This prospective study demonstrated that CE identifies significantly more small bowel polyps compared with MRE in patients with PJS. Correlation between the two techniques and subsequent BE however was relatively poor.
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- 2014
14. Pentenary GaInAsPSb for mid-infrared light-emitting diodes and lasers grown by liquid phase epitaxy - art. no. 647918
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Razeghi, M, Brown, GJ, Smirnov, V. M., Batty, P. J., Krier, A., Jones, Robert, Razeghi, M, Brown, GJ, Smirnov, V. M., Batty, P. J., Krier, A., and Jones, Robert
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GaInAsPSb is a new narrow gap semiconductor material, which is suitable for the fabrication of semiconductor light sources for the mid-infrared spectral range. Unique physical properties of the alloy are discussed and its advantages for mid-infrared optoelectronic devices are considered. Liquid phase epitaxy (LPE) growth conditions for GaInAsPSb homogeneous high crystal quality layers lattice-matched onto GaSb substrates were determined. Spectra of photoluminescence (PL) emission were investigated. Homejunction p-i-n light-emitting diodes (LEDs) based on this pentenary alloy were fabricated and electroluminescence (EL) peaking near 4.0 mu m at room temperature was observed.
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- 2007
15. U.W.O.A.S. Symposium Abstracts 2005
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Hamilton, Anne, primary, Blainey, Marc, additional, Little, Christopher, additional, Eramian, Laura, additional, Parker, Elias, additional, Pineda, Carolina, additional, and Brown, GJ, additional
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- 2011
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16. Quantitative Chemical Mapping of Engineered Interfaces in Quaternary III-V Semiconductor Heterostructures Using Phase Retrieval High Resolution Transmission Electron Microscopy
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Mahalingam, K, primary, Haugan, HJ, additional, Brown, GJ, additional, and Eyink, KG, additional
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- 2008
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17. Single-dose intravenous salbutamol bolus for managing children with acute severe asthma in the emergency department: reanalysis of data.
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Brown GJ and Lam LT
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- 2002
18. Light scattering by inclusions in crystals
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Brown Gj and Hopkins Fk
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Optics ,Materials science ,business.industry ,Scattering ,Materials Science (miscellaneous) ,Attenuation coefficient ,Dispersion (optics) ,Business and International Management ,Inclusion (mineral) ,business ,Refractive index ,Industrial and Manufacturing Engineering ,Light scattering - Abstract
Optical transmission data can aid in the analysis of nonabsorbing inclusions in crystals. For illustration, the inclusions in a AgGaSe(2) sample are analyzed.
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- 1991
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19. The development of permanent unidirectional anterograde block in the accessory pathway of a patient with Wolff-Parkinson-White syndrome and observations on the mechanism of the ensuing incessant circus tachycardia
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Miller Hc, K G Lowe, and Brown Gj
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Tachycardia ,medicine.medical_specialty ,business.industry ,General Medicine ,Accessory pathway ,Middle Aged ,Heart Conduction System ,Anesthesia ,Internal medicine ,Cardiology ,Medicine ,Humans ,Wolff-Parkinson-White Syndrome ,cardiovascular diseases ,medicine.symptom ,business - Abstract
A case is reported, the sixth in the literature, in which permanent anterograde block occurred in the accessory pathway of a patient with Wolff-Parkinson-White syndrome, so that pre-excitation no longer occurred. Retrograde conduction remained intact and the patient developed incessant tachycardia with ventriculo-atrial conduction occurring over the accessory pathway. Retrogradely conducting pathways are a common cause of supraventricular tachycardia and this case raises the possibility that many of them may previously have had overt pre-excitation.
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- 1981
20. Towards p-type doping of ZnO by ion implantation
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Coleman, Va, Tan, Hh, Jagadish, C., Kucheyev, So, Phillips, MR, Jin Zou, Brown, Gj, Biefeld, Rm, Gmachl, C., Manasreh, Mo, and Unterrainer, K.
21. Improved performance of GaSb-based MIR photodetectors through electrochemical passivation in sulphur containing solutions
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Piotrowska, A., Papis, E., Golaszewska, K., Lukasiewicz, R., Kaminska, E., Piotrowski, Tt, Kruszka, R., Kudla, A., Rutkowski, J., Szade, J., Winiarski, A., Wawro, A., Aleszkiewicz, M., Brown, Gj, Biefeld, Rm, Gmachl, C., Manasreh, Mo, and Karl Unterrainer
22. Optically-pumped continuous-wave terahertz sources
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Xavier Wallart, Jean-Francois Lampin, Emilien Peytavit, Guillaume Ducournau, Mohammed Zaknoune, P. Latzel, Fabio Pavanello, Institut d’Électronique, de Microélectronique et de Nanotechnologie - UMR 8520 (IEMN), Centrale Lille-Institut supérieur de l'électronique et du numérique (ISEN)-Université de Valenciennes et du Hainaut-Cambrésis (UVHC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Université Polytechnique Hauts-de-France (UPHF), Photonique THz - IEMN (PHOTONIQUE THz - IEMN), Centrale Lille-Institut supérieur de l'électronique et du numérique (ISEN)-Université de Valenciennes et du Hainaut-Cambrésis (UVHC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Université Polytechnique Hauts-de-France (UPHF)-Centrale Lille-Institut supérieur de l'électronique et du numérique (ISEN)-Université de Valenciennes et du Hainaut-Cambrésis (UVHC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Université Polytechnique Hauts-de-France (UPHF), Advanced NanOmeter DEvices - IEMN (ANODE - IEMN), EPItaxie et PHYsique des hétérostructures - IEMN (EPIPHY - IEMN), SPIE, Razeghi, M, Tournie, E, Brown, GJ, and Photonique THz - IEMN (PHOTONIQ THz - IEMN)
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photoconductor ,Materials science ,business.industry ,Terahertz radiation ,uni-travelling carrier photodiode ,Impedance matching ,Photodetector ,low-temperature-grown GaAs ,Laser ,Terahertz sources ,7. Clean energy ,photomixing ,thermocompression bonding ,Photodiode ,law.invention ,Photomixing ,Optical pumping ,High impedance ,Optics ,law ,[SPI.OPTI]Engineering Sciences [physics]/Optics / Photonic ,Optoelectronics ,photomixer ,business - Abstract
International audience; Recently we have improved the efficiency and the output power of our optically pumped continuous-wave THz sources. These sources are based on the beating of two laser lines in a wide bandwidth photodetector. Its intrinsic nonlinear behaviour is used to produce a beatnote at the frequency difference between the two laser lines (photomixing). These photomixers are continuously tunable THz sources working at room temperature. We have developed two kinds of photomixers: GaAs-based for 0.8 mu m pumping and InP-based for 1.5 mu m pumping. On GaAs the best results has been obtained thanks to low-temperature-grown GaAs (LTG-GaAs) photoconductors (PC). Efficiency and power were optimized by designing a new type of thin PC placed in a Fabry-Perot resonator. The high impedance of the PC is a well-known limitation of this device but with our approach it was possible to reduce its impedance by a factor 100. Moreover by designing an impedance matching network it was possible to obtain 1.8 mW at 252 GHz with a total efficiency of 0.5 %. On InP the best results are obtained with uni-travelling-carrier photodiodes (UTC-PD). The device was improved by designing a new heterostructure and new semi-transparent contacts with sub-wavelength apertures. The active layer was also bonded to a silicon substrate thanks to metal thermocompression. It is demonstrated that with this approach it is possible to obtain a power of 0.7 mW at 300 GHz with a total efficiency of 0.7 %. More generally the efficiency of optically pumped terahertz sources will be discussed.
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- 2015
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23. Design and applications of flexible photonic membranes
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Andrea Di Falco, Peter Reader-Harris, Blair C. Kirkpatrick, Razeghi, M, Tournie, E, Brown, GJ, EPSRC, and University of St Andrews. School of Physics and Astronomy
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Fabrication ,Light ,Computer science ,business.industry ,Filter ,Spectral filtering ,Physics::Optics ,Nanotechnology ,Potential method ,Flexible plasmonics ,Optical tweezers ,Lab-on-fibre ,Self-assembled monolayers ,Membrane ,QC Physics ,Filter (video) ,Display ,Photonics ,Optical filter ,business ,Angular tolerant ,QC - Abstract
ADF acknowledges support from EPSRC (EP/I004602/1 and EP/J004200/1). In this paper we present the design and applications of flexible photonic membranes. We discuss their use as versatile photonic layers in the framework of lab-on-fibre applications, specifically focusing on the design of angular robust spectral filters. We also show alternative routes to their fabrication, highlighting the opportunities and limitations associated to each approach. Finally we present our preliminary results on the all-optical control over flexible membranes, as a potential method to fine-tune their opto-mechanical properties to the required application. Publisher PDF
- Published
- 2014
24. Mid-IR heterogeneous silicon photonics
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Noel Healy, Richard M. Osgood, Aditya Malik, Alban Gassenq, Goran Z. Mashanovich, Eva Ryckeboer, Gunther Roelkens, Roel Baets, Li Shen, Utsav D. Dave, Nannicha Hattasan, Chen Hu, Sarah Uvin, Laurent Cerutti, Jean-Baptiste Rodriguez, Bart Kuyken, Zeger Hens, Xia Chen, Yosuke Shimura, Milos Nedeljkovic, Xiaoping Liu, Anna C. Peacock, Federica Gencarelli, Joris Van Campenhout, Muhammad Muneeb, Eric Tournié, William M. J. Green, Roger Loo, François Leo, Benjamin Vincent, Razeghi, M, Tournie, E, and Brown, GJ
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Materials science ,Technology and Engineering ,Silicon ,Hybrid silicon laser ,SPECTROMETERS ,mid-infrared spectroscopy ,Photodetector ,chemistry.chemical_element ,Physics::Optics ,02 engineering and technology ,ON-INSULATOR ,01 natural sciences ,GAINASSB PHOTODIODES ,law.invention ,010309 optics ,Condensed Matter::Materials Science ,WAVE-GUIDES ,law ,0103 physical sciences ,Astrophysics::Galaxy Astrophysics ,Silicon photonics ,business.industry ,CHIP ,Photonic integrated circuit ,Nonlinear optics ,021001 nanoscience & nanotechnology ,Semiconductor ,chemistry ,photonic integration ,Optoelectronics ,0210 nano-technology ,business ,Waveguide - Abstract
In this paper we present our recent work on mid-infrared photonic integrated circuits for spectroscopic sensing applications. We discuss the use of silicon-based photonic integrated circuits (either based on silicon-on-insulator or germanium-on-silicon waveguide circuits) for this purpose and detail how a variety of optical functions in the mid-infrared besides passive waveguiding and filtering can be realized, either relying on nonlinear optics or on the integration of other materials such as GaSb-based compound semiconductors, GeSn epitaxy and PbS colloidal nanoparticles. The integration of photodetectors resulting in fully integrated mid-IR spectrometers, semiconductor laser sources and nonlinear optics based spectral translators between the telecommunication wavelength range and the mid-infrared are discussed.
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- 2013
25. Short-wave infrared colloidal quantum dot photodetectors on silicon
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Yolanda Justo, Wolfgang Heiss, Gunther Roelkens, Zeger Hens, Chen Hu, Alban Gassenq, Sergii Yakunin, Razeghi, Manijeh, Tournie, E, and Brown, GJ
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Materials science ,Silicon ,chemistry.chemical_element ,Photodetector ,Nanotechnology ,02 engineering and technology ,Substrate (electronics) ,010402 general chemistry ,colloidal quantum dots ,01 natural sciences ,Responsivity ,photoconductor ,business.industry ,Photoconductivity ,021001 nanoscience & nanotechnology ,0104 chemical sciences ,solid-state ligand exchange ,NANOCRYSTALS ,chemistry ,Nanocrystal ,Physics and Astronomy ,Quantum dot ,Optoelectronics ,Charge carrier ,0210 nano-technology ,business - Abstract
In this paper, two kinds of colloidal quantum dots, PbS and HgTe, are explored for SWIR photodetectors application. The colloidal dots are prepared by hot injection chemical synthesis, with organic ligands around the dots keeping them stable in solution. For the purpose of achieving efficient carrier transport between the dots in a film, these long organic ligands are replaced by shorter, inorganic ligands. We report uniform, ultra-smooth colloidal QD films without cracks realized by dip-coating and corresponding ligand exchange on a silicon substrate. Metal-free inorganic ligands, such as OH- and S2-, are investigated to facilitate the charge carrier transport in the film. Both PbS and HgTe-based quantum dot photoconductors were fabricated on interdigitated gold electrodes. For PbS-based detectors a responsivity of 200A/W is measured at 1.5μm, due to the large internal photoconductive gain. A 2.2μm cut-off wavelength for PbS photodetectors and 2.8μm for HgTe quantum dot photodetectors are obtained.
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- 2013
26. Integrated thin-film GaSb-based Fabry-Perot lasers: towards a fully integrated spectrometer on a SOI waveguide circuit
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Jean-Baptiste Rodriguez, Eric Tournié, Laurent Cerutti, Alban Gassenq, Gunther Roelkens, Nannicha Hattasan, Razeghi, M, Tournie, E, Brown, GJ, Institut d’Electronique et des Systèmes (IES), Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Composants à Nanostructure pour le moyen infrarouge (NANOMIR), and Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)
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Materials science ,Technology and Engineering ,NEAR-INFRARED SPECTROSCOPY ,MU-M ,Physics::Optics ,Silicon on insulator ,02 engineering and technology ,GaSb lasers ,01 natural sciences ,7. Clean energy ,integrated laser ,law.invention ,010309 optics ,020210 optoelectronics & photonics ,law ,0103 physical sciences ,0202 electrical engineering, electronic engineering, information engineering ,Absorption (electromagnetic radiation) ,business.industry ,CHIP ,Photonic integrated circuit ,Detector ,PHOTODIODES ,short-wave infrared ,SOI photonic integrated circuit ,Laser ,[SPI.TRON]Engineering Sciences [physics]/Electronics ,Photodiode ,BCB bonding ,ROOM-TEMPERATURE ,Optoelectronics ,business ,Waveguide ,Fabry–Pérot interferometer - Abstract
International audience; Several molecules of interest have their absorption signature in the mid-infrared. Spectroscopy is commonly used for the detection of these molecules, especially in the short-wave infrared (SWIR) region due to the low water absorption. Conventional spectroscopic systems consist of a broadband source, detector and dispersive components, making them bulky and difficult to handle. Such systems cannot be used in applications where small footprint and low power consumption is critical, such as portable gas sensors and implantable blood glucose monitors. Silicon-On-Insulator (SOI) offers a compact, low-cost photonic integrated circuit platform realized using CMOS fabrication technology. On the other hand, the GaSb material system allows the realization of high performance SWIR lasers and detectors. Integration of GaSb active components on SOI could therefore result in a compact and low power consumption integrated spectroscopic system. In this paper, we report the study on thin-film GaSb Fabry-Perot lasers integrated on a carrier substrate. The integration is achieved by using an adhesive polymer (DVS-BCB) as the bonding agent. The lasers operate at room temperature at 2.02μm. We obtain a minimum threshold current of 48.9mA in the continuous wave regime and 27.7mA in pulsed regime. This yields a threshold current density of 680A/cm2 and 385A/cm2, respectively. The thermal behaviour of the device is also studied. The lasers operate up to 35 °C, due to a 323 K/W thermal resistance
- Published
- 2013
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27. Thermal Decomposition of 2-Cyclopentenone.
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Narkin K, Legg HR, Brown GJ, El-Shazly K, Martin TD, Jarrell M, McCunn LR, Chen Z, and Parish CA
- Abstract
The thermal decomposition of 2-cyclopentenone, a cyclic oxygenated hydrocarbon that occurs in the pyrolysis of biomass, has been studied in a combined experimental and theoretical approach. Gas-phase pyrolysis was performed at temperatures ranging from 1000 to 1400 K in a pulsed, microtubular reactor. Products were identified by FTIR spectroscopy following their isolation in a low-temperature argon matrix. The following products were identified: carbon monoxide, ketene, propenylketene, vinylacetylene, ethylene, propene, acrolein, acetylene, propyne, and propargyl radical. Computational results identify three different decomposition channels involving a H atom migration, and producing prop-2-enylketene (Pathway 1), prop-1-enylketene (Pathway 2), and a second conformation of prop-2-enylketene (Pathway 3). A fourth decomposition pathway involves simultaneous rupture of two C-C bonds forming a high energy cyclopropenone intermediate that further reacts to form ethylene, acetylene, and carbon monoxide. Finally, a fifth pathway to the formation of acrolein and acetylene was identified that proceeds via a multistep mechanism, and an interconversion from 2-cyclopentenone to 3-cyclopentenone was identified computationally, but not observed experimentally.
- Published
- 2024
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28. A TNIP1-driven systemic autoimmune disorder with elevated IgG4.
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Medhavy A, Athanasopoulos V, Bassett K, He Y, Stanley M, Enosi Tuipulotu D, Cappello J, Brown GJ, Gonzalez-Figueroa P, Turnbull C, Shanmuganandam S, Tummala P, Hart G, Lea-Henry T, Wang H, Nambadan S, Shen Q, Roco JA, Burgio G, Wu P, Cho E, Andrews TD, Field MA, Wu X, Ding H, Guo Q, Shen N, Man SM, Jiang SH, Cook MC, and Vinuesa CG
- Subjects
- Animals, Humans, Mice, Female, Male, Signal Transduction, Mitochondria metabolism, Exome Sequencing, Antibodies, Antinuclear immunology, B-Lymphocytes immunology, Mice, Knockout, Mice, Inbred C57BL, Germinal Center immunology, Pedigree, Salivary Glands immunology, Salivary Glands metabolism, Salivary Glands pathology, Membrane Glycoproteins, Immunoglobulin G immunology, Immunoglobulin G metabolism, Toll-Like Receptor 7 metabolism, Toll-Like Receptor 7 genetics, Toll-Like Receptor 7 immunology, Myeloid Differentiation Factor 88 metabolism, Myeloid Differentiation Factor 88 genetics, Autoimmune Diseases immunology, Autoimmune Diseases genetics, DNA-Binding Proteins metabolism, DNA-Binding Proteins genetics
- Abstract
Whole-exome sequencing of two unrelated kindreds with systemic autoimmune disease featuring antinuclear antibodies with IgG4 elevation uncovered an identical ultrarare heterozygous TNIP1
Q333P variant segregating with disease. Mice with the orthologous Q346P variant developed antinuclear autoantibodies, salivary gland inflammation, elevated IgG2c, spontaneous germinal centers and expansion of age-associated B cells, plasma cells and follicular and extrafollicular helper T cells. B cell phenotypes were cell-autonomous and rescued by ablation of Toll-like receptor 7 (TLR7) or MyD88. The variant increased interferon-β without altering nuclear factor kappa-light-chain-enhancer of activated B cells signaling, and impaired MyD88 and IRAK1 recruitment to autophagosomes. Additionally, the Q333P variant impaired TNIP1 localization to damaged mitochondria and mitophagosome formation. Damaged mitochondria were abundant in the salivary epithelial cells of Tnip1Q346P mice. These findings suggest that TNIP1-mediated autoimmunity may be a consequence of increased TLR7 signaling due to impaired recruitment of downstream signaling molecules and damaged mitochondria to autophagosomes and may thus respond to TLR7-targeted therapeutics., (© 2024. The Author(s).)- Published
- 2024
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29. Rare SH2B3 coding variants in lupus patients impair B cell tolerance and predispose to autoimmunity.
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Zhang Y, Morris R, Brown GJ, Lorenzo AMD, Meng X, Kershaw NJ, Kiridena P, Burgio G, Gross S, Cappello JY, Shen Q, Wang H, Turnbull C, Lea-Henry T, Stanley M, Yu Z, Ballard FD, Chuah A, Lee JC, Hatch AM, Enders A, Masters SL, Headley AP, Trnka P, Mallon D, Fletcher JT, Walters GD, Šestan M, Jelušić M, Cook MC, Athanasopoulos V, Fulcher DA, Babon JJ, Vinuesa CG, and Ellyard JI
- Subjects
- Animals, Humans, Mice, B-Cell Activating Factor metabolism, B-Lymphocytes, Precursor Cells, B-Lymphoid, Autoimmunity genetics, Lupus Erythematosus, Systemic genetics
- Abstract
Systemic lupus erythematosus (SLE) is a heterogeneous autoimmune disease with a clear genetic component. While most SLE patients carry rare gene variants in lupus risk genes, little is known about their contribution to disease pathogenesis. Amongst them, SH2B3-a negative regulator of cytokine and growth factor receptor signaling-harbors rare coding variants in over 5% of SLE patients. Here, we show that unlike the variant found exclusively in healthy controls, SH2B3 rare variants found in lupus patients are predominantly hypomorphic alleles, failing to suppress IFNGR signaling via JAK2-STAT1. The generation of two mouse lines carrying patients' variants revealed that SH2B3 is important in limiting the number of immature and transitional B cells. Furthermore, hypomorphic SH2B3 was shown to impair the negative selection of immature/transitional self-reactive B cells and accelerate autoimmunity in sensitized mice, at least in part due to increased IL-4R signaling and BAFF-R expression. This work identifies a previously unappreciated role for SH2B3 in human B cell tolerance and lupus risk., (© 2024 Zhang et al.)
- Published
- 2024
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30. Screening and confirmation of psilocin, mitragynine, phencyclidine, ketamine and ketamine metabolites by liquid chromatography-tandem mass spectrometry.
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Wood ME, Brown GJ, Karschner EL, Seither JZ, Brown JT, Knittel JL, and Walterscheid JP
- Subjects
- Humans, Phencyclidine, Tandem Mass Spectrometry methods, Chromatography, Liquid methods, Ketamine, Psilocybin analogs & derivatives, Secologanin Tryptamine Alkaloids
- Abstract
A safe and productive workplace requires a sober workforce, free from substances that impair judgment and concentration. Although drug monitoring programs already exist, the scope and loopholes of standard workplace testing panels are well known, allowing other substances to remain a source of risk. Therefore, a high-throughput urine screening method for psilocin, mitragynine, phencyclidine, ketamine, norketamine and dehydronorketamine was developed and validated in conjunction with a urine and blood confirmation method. There are analytical challenges to overcome with psilocin and mitragynine, particularly when it comes to drug stability and unambiguous identification in authentic specimens. Screening and confirmation methods were validated according to the American National Standards Institute/Academy Standards Board (ANSI/ASB) Standard 036, Standard Practices for Method Validation in Forensic Toxicology. An automated liquid handling system equipped with dispersive pipette extraction tips was utilized for preparing screening samples, whereas an offline solid-phase extraction method was used for confirmation sample preparation. Both methods utilized liquid chromatography-tandem mass spectrometry to achieve limits of detection between 1-5 ng/mL for the screening method and 1 ng/mL for the confirmation method. Automation allows for faster throughput and enhanced quality assurance, which improves turnaround time. Compared to previous in-house methods, specimen volumes were substantially decreased for both blood and urine, which is an advantage when volume is limited. This screening technique is well suited for evaluating large numbers of specimens from those employed in safety-sensitive workforce positions. This method can be utilized by workplace drug testing, human performance and postmortem laboratories seeking robust qualitative screening and confirmation methods for analytes that have traditionally been challenging to routinely analyze., (Published by Oxford University Press 2024. This work is written by (a) US Government employee(s) and is in the public domain in the US.)
- Published
- 2024
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31. DECTIN-1: A modifier protein in CTLA-4 haploinsufficiency.
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Turnbull C, Bones J, Stanley M, Medhavy A, Wang H, Lorenzo AMD, Cappello J, Shanmuganandam S, Pandey A, Seneviratne S, Brown GJ, Meng X, Fulcher D, Burgio G, Man SM, de Lucas Collantes C, Gasior M, López Granados E, Martin P, Jiang SH, Cook MC, Ellyard JI, Athanasopoulos V, Corry B, Canete PF, and Vinuesa CG
- Subjects
- Animals, Humans, Mice, Autoimmunity, CTLA-4 Antigen genetics, Haploinsufficiency, Lectins, C-Type genetics
- Abstract
Autosomal dominant loss-of-function (LoF) variants in cytotoxic T-lymphocyte associated protein 4 ( CTLA4 ) cause immune dysregulation with autoimmunity, immunodeficiency and lymphoproliferation (IDAIL). Incomplete penetrance and variable expressivity are characteristic of IDAIL caused by CTLA-4 haploinsufficiency (CTLA-4h), pointing to a role for genetic modifiers. Here, we describe an IDAIL proband carrying a maternally inherited pathogenic CTLA4 variant and a paternally inherited rare LoF missense variant in CLEC7A, which encodes for the β-glucan pattern recognition receptor DECTIN-1. The CLEC7A variant led to a loss of DECTIN-1 dimerization and surface expression. Notably, DECTIN-1 stimulation promoted human and mouse regulatory T cell (T
reg ) differentiation from naïve αβ and γδ T cells, even in the absence of transforming growth factor-β. Consistent with DECTIN-1's Treg -boosting ability, partial DECTIN-1 deficiency exacerbated the Treg defect conferred by CTL4-4h. DECTIN-1/ CLEC7A emerges as a modifier gene in CTLA-4h, increasing expressivity of CTLA4 variants and acting in functional epistasis with CTLA-4 to maintain immune homeostasis and tolerance.- Published
- 2023
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32. Acoustic Screening for Obstructive Sleep Apnea in Home Environments Based on Deep Neural Networks.
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Romero HE, Ma N, Brown GJ, and Hill EA
- Subjects
- Acoustics, Home Environment, Humans, Neural Networks, Computer, Respiratory Sounds, Sleep Apnea, Obstructive diagnosis
- Abstract
Obstructive sleep apnea (OSA) is a chronic and prevalent condition with well-established comorbidities. However, many severe cases remain undiagnosed due to poor access to polysomnography (PSG), the gold standard for Obstructive sleep apnea (OSA) diagnosis. Accurate home-based methods to screen for OSA are needed, which can be applied inexpensively to high-risk subjects to identify those that require PSG to fully assess their condition. A number of methods that analyse speech or breathing sounds to screen for OSA have been previously investigated. However, these methods have constraints that limit their use in home environments (e.g., they require specialised equipment, are not robust to background noise, are obtrusive or depend on tightly controlled conditions). This paper proposes a novel method to screen for OSA, which analyses sleep breathing sounds recorded with a smartphone at home. Audio recordings made over a whole night are divided into segments, each of which is classified for the presence or absence of OSA by a deep neural network. The apnea-hypopnea index estimated from the segments predicted as containing evidence of OSA is then used to screen for the condition. Audio recordings made during home sleep apnea testing from 103 participants for 1 or 2 nights were used to develop and evaluate the proposed system. When screening for moderate OSA the acoustics based system achieved a sensitivity of 0.79 and a specificity of 0.80. The sensitivity and specificity when screening for severe OSA were 0.78 and 0.93, respectively. The system is suitable for implementation on consumer smartphones.
- Published
- 2022
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33. TLR7 gain-of-function genetic variation causes human lupus.
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Brown GJ, Cañete PF, Wang H, Medhavy A, Bones J, Roco JA, He Y, Qin Y, Cappello J, Ellyard JI, Bassett K, Shen Q, Burgio G, Zhang Y, Turnbull C, Meng X, Wu P, Cho E, Miosge LA, Andrews TD, Field MA, Tvorogov D, Lopez AF, Babon JJ, López CA, Gónzalez-Murillo Á, Garulo DC, Pascual V, Levy T, Mallack EJ, Calame DG, Lotze T, Lupski JR, Ding H, Ullah TR, Walters GD, Koina ME, Cook MC, Shen N, de Lucas Collantes C, Corry B, Gantier MP, Athanasopoulos V, and Vinuesa CG
- Subjects
- Animals, Autoimmunity genetics, B-Lymphocytes, Cyclic GMP analogs & derivatives, Guanosine, Humans, Mice, Myeloid Differentiation Factor 88 genetics, Myeloid Differentiation Factor 88 metabolism, Gain of Function Mutation, Lupus Erythematosus, Systemic genetics, Toll-Like Receptor 7 genetics, Toll-Like Receptor 7 metabolism
- Abstract
Although circumstantial evidence supports enhanced Toll-like receptor 7 (TLR7) signalling as a mechanism of human systemic autoimmune disease
1-7 , evidence of lupus-causing TLR7 gene variants is lacking. Here we describe human systemic lupus erythematosus caused by a TLR7 gain-of-function variant. TLR7 is a sensor of viral RNA8 ,9 and binds to guanosine10 -12 . We identified a de novo, previously undescribed missense TLR7Y264H variant in a child with severe lupus and additional variants in other patients with lupus. The TLR7Y264H variant selectively increased sensing of guanosine and 2',3'-cGMP10-12 , and was sufficient to cause lupus when introduced into mice. We show that enhanced TLR7 signalling drives aberrant survival of B cell receptor (BCR)-activated B cells, and in a cell-intrinsic manner, accumulation of CD11c+ age-associated B cells and germinal centre B cells. Follicular and extrafollicular helper T cells were also increased but these phenotypes were cell-extrinsic. Deficiency of MyD88 (an adaptor protein downstream of TLR7) rescued autoimmunity, aberrant B cell survival, and all cellular and serological phenotypes. Despite prominent spontaneous germinal-centre formation in Tlr7Y264H mice, autoimmunity was not ameliorated by germinal-centre deficiency, suggesting an extrafollicular origin of pathogenic B cells. We establish the importance of TLR7 and guanosine-containing self-ligands for human lupus pathogenesis, which paves the way for therapeutic TLR7 or MyD88 inhibition., (© 2022. The Author(s).)- Published
- 2022
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34. The Dewey Monitor: Pulse Oximetry can Warn of Hypoxia in an Immersed Rebreather Diver in Multiple Scenarios.
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Lance RM, Natoli MJ, Di Pumpo F, Beck TP, Gatrell A, Brown GJ, Schocken D, and Moon RE
- Subjects
- Adult, Equipment Failure, Humans, Hypoxia etiology, Male, Respiration, Diving adverse effects, Hyperbaric Oxygenation adverse effects, Hypoxia prevention & control, Monitoring, Physiologic instrumentation, Oximetry instrumentation
- Abstract
Divers who wish to prolong their time underwater while carrying less equipment often use devices called rebreathers, which recycle the gas expired after each breath instead of discarding it as bubbles. However, rebreathers' need to replace oxygen used by breathing creates a failure mechanism that can and frequently does lead to hypoxia, loss of consciousness, and death. The purpose of this study was to determine whether a pulse oximeter could provide a useful amount of warning time to a diver with a rebreather after failure of the oxygen addition mechanism. Twenty-eight volunteer human subjects breathed on a mixed-gas rebreather in which the oxygen addition system had been disabled. The subjects were immersed in water in four separate environmental scenarios, including cold and warm water, and monitored using pulse oximeters placed at multiple locations. Pulse oximeters placed on the forehead and clipped on the nasal ala provided a mean of 32 s (±10 s SD) of warning time to divers with falling oxygen levels, prior to risk of loss of consciousness. These devices, if configured for underwater use, could provide a practical and inexpensive alarm system to warn of impending loss of consciousness in a manner that is redundant to the rebreather., (© 2022. The Author(s) under exclusive licence to Biomedical Engineering Society.)
- Published
- 2022
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35. Testing of full face snorkel masks to examine recreational snorkeler deaths.
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Farrell J, Natoli MJ, Brown GJ, Yook A, and Lance RM
- Subjects
- Carbon Dioxide, Exercise physiology, Humans, Pulmonary Gas Exchange, Respiration, Diving adverse effects
- Abstract
A recent rise in snorkeling-related deaths in Hawaii has inspired several bans on full face snorkel masks (FFSMs). However, while there are theories to explain the deaths, little physiological data exists about the way the FFSMs provide gas to an exercising subject. To evaluate the safety of the FFSM concept, this study was designed to test how use of a full face snorkel mask (FFSM) may be physiologically different than use of a conventional snorkel, and to assess if any of those differences could lead to increased risk for the snorkeler. Ten (10) volunteer human subjects were tested using a variety of commercially available FFSMs, with real-time monitoring of blood oxygen saturation (SpO2), inspired airway pressure, and inspired and expired levels of carbon dioxide and oxygen. Two of the three FFSM design types were shown not to function as advertised, but none of the masks provided physiologically problematic gas supplies to the snorkelers. While this testing yielded no conclusive "smoking gun" to explain the snorkeler deaths, some of the mask models showed patterns of increasing breathing resistance with water intrusion because of a shared design characteristic, and this increased resistance could potentially create elevated levels of respiratory distress to snorkelers during real-world use., Competing Interests: The authors of this paper declare no conflicts of interest exist with this submission., (Copyright© Undersea and Hyperbaric Medical Society.)
- Published
- 2022
36. Critical peptic ulcer bleeding requiring massive blood transfusion: outcomes of 270 cases.
- Author
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Ket SN, Sparrow RL, McQuilten ZK, Gibson PR, Brown GJ, and Wood EM
- Subjects
- Adult, Aged, Australia epidemiology, Blood Transfusion, Humans, Male, Registries, Peptic Ulcer complications, Peptic Ulcer epidemiology, Peptic Ulcer therapy, Peptic Ulcer Hemorrhage diagnosis, Peptic Ulcer Hemorrhage therapy
- Abstract
Background: Critical peptic ulcer bleeding requiring massive transfusion is a gastroenterological emergency. Few data exist on management and outcomes. The Australian and New Zealand Massive Transfusion Registry collects comprehensive data on adult patients receiving massive transfusion across all bleeding contexts., Aim: To evaluate clinical factors, management (procedural interventions, transfusions) and outcomes after massive transfusion for critical peptic ulcer bleeding., Method: Demographics, diagnosis, procedures and mortality data were available for 5482 massive transfusion cases from 23 hospitals. International Classification of Diseases 10th Edition, Australian Modification codes were used to determine peptic ulcer bleeding and the Australian Classification of Health Intervention for interventions (i.e. endoscopic, radiological, surgical)., Results: Peptic ulcer bleeding accounted for 270 (4.9%) of all in-hospital massive transfusion cases; 70% were male. Median number of red blood cell (RBC) units transfused was 7 (interquartile range, 6-10). Thirty-day mortality was 19.6%. Age (75 vs 67 years; P = 0.009) and Charlson Comorbidity Index (3 vs 1; P < 0.001) were higher in those who died. Highest 24-h international normalised ratio (1.5 vs 1.4; P < 0.001) and creatinine (118 μmol/L vs 96 μmol/L; P = 0.03) and nadir platelet count (86 × 10
9 /L vs 118 × 109 /L; P = 0.01) were also associated with 30-day mortality. There were no differences in mortality according to number of RBC, platelets or plasma units transfused, gastroscopy (with or without intervention), interventional radiology or surgery., Conclusion: One in five patients with critical peptic ulcer bleeding requiring massive transfusion died by 30 days. Mortality was associated with patient characteristics rather than clinical interventions (e.g. procedures, blood product transfusion)., (© 2020 Royal Australasian College of Physicians.)- Published
- 2021
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37. Canine-specific tail-in, head-out sperm agglutination.
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Brown GJ, Nöthling JO, and De Cramer KGM
- Subjects
- Animals, Dogs, Horses, Infertility, Male veterinary, Male, Semen immunology, Sheep, Sperm Motility, Spermatozoa immunology, Dog Diseases immunology, Sperm Agglutination, Sperm Tail immunology
- Abstract
An interesting pattern of tail-in, head-out sperm agglutination was identified in a Brucella canis seronegative subfertile dog. Centrifuged seminal plasma from this dog could induce a similar pattern of agglutination in six other dogs, but not in ejaculates from a single stallion and two rams. The agglutination pattern was short-lived and appeared to depend on motility of spermatozoa, although intensity of agglutination may have been affected by concentration of agglutinating factor., (© 2021 Wiley-VCH GmbH.)
- Published
- 2021
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38. Vibrational Bands of the 2-Butyn-1-yl Radical.
- Author
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Brown GJ, Ellis MJ, Martin TD, and McCunn LR
- Abstract
The 2-butyn-1-yl radical is an isomer of C
4 H5 and is structurally similar to the propargyl radical, which is the simplest resonance-stabilized hydrocarbon radical. The C4 H5 radical is likely to be important to astrochemistry and combustion, similar to propargyl, yet little research has been done on its spectroscopic properties. In this work, seven vibrational bands of the 2-butyn-1-yl radical are reported. The radical was formed by pyrolysis of 1-bromo-2-butyne at 800 K and isolated in a low-temperature argon matrix. The experimentally observed frequencies and intensities of the seven vibrational bands were found to be consistent with QCISD predictions from the literature and with new B3LYP calculations in this work.- Published
- 2020
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39. Clinical coding data algorithm to categorize type of gastrointestinal bleeding as a primary reason for massive transfusion: results from the Australian and New Zealand Massive Transfusion Registry.
- Author
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Ket SN, Sparrow RL, McQuilten ZK, Tacey M, Gibson PR, Brown GJ, and Wood EM
- Subjects
- Adult, Aged, Algorithms, Australia, Clinical Coding standards, Cohort Studies, Female, Gastrointestinal Hemorrhage therapy, Humans, Male, Middle Aged, New Zealand, Retrospective Studies, Blood Transfusion standards, Clinical Coding methods, Gastrointestinal Hemorrhage classification, Registries
- Abstract
Background: Management of major gastrointestinal bleeding (GIB) may require massive transfusion (MT), but limited data are available. Upper and lower GIB have different aetiologies, prognosis, bleeding patterns and outcomes. Better understanding of current transfusion management and outcomes in these patients is important. We sought to define and validate an algorithm based on clinical coding data to distinguish critical upper and lower GIB using data from the Australian and New Zealand Massive Transfusion Registry (ANZ-MTR)., Study Design and Methods: Australian and New Zealand Massive Transfusion Registry hospital-source data on adult patients receiving a MT (defined as ≥5 red cell units within 4 h) for any bleeding context were used. An algorithm allocating ICD-10-AM codes into 'probable' or 'possible' causes of GIB was developed and applied to the ANZ-MTR. Source medical records of 69 randomly selected cases were independently reviewed to validate the algorithm., Results: Of 5482 MT cases available from 25 hospitals, 716 (13%) were identified as GIB with 538/716 (75%) categorized 'probable' and 178/716 'possible' GIB. Upper and lower GIB causes of MT were identified for 455/538 (85%) and 76/538 (14%) 'probable' cases, respectively; 7/538 (1·3%) cases had both upper and lower GIB. Allocation by the algorithm into a 'probable' GIB category had a 95·7% (CI: 90-100%) positive predictive value when validated against source medical records., Conclusion: An algorithm based on ICD-10-AM codes can be used to accurately categorize patients with luminal GIB as the primary reason for MT, enabling further study of this critically unwell and resource-intensive cohort of patients., (© 2019 International Society of Blood Transfusion.)
- Published
- 2019
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40. Talking in Time : The development of a self-administered conversation analysis based training programme for cochlear implant users.
- Author
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Wells B, Beeston AV, Bradley E, Brown GJ, Crook H, and Kurtić E
- Subjects
- Communication, Deafness psychology, Humans, Language, Program Evaluation, Software, Cochlear Implantation rehabilitation, Cochlear Implants, Correction of Hearing Impairment methods, Deafness rehabilitation, Speech Therapy methods
- Abstract
Objectives: Training software to facilitate participation in conversations where overlapping talk is common was to be developed with the involvement of Cochlear implant (CI) users. Methods: Examples of common types of overlap were extracted from a recorded corpus of 3.5 hours of British English conversation. In eight meetings, an expert panel of five CI users tried out ideas for a computer-based training programme addressing difficulties in turn-taking. Results: Based on feedback from the panel, a training programme was devised. The first module consists of introductory videos. The three remaining modules, implemented in interactive software, focus on non-overlapped turn-taking, competitive overlaps and accidental overlaps. Discussion: The development process is considered in light of feedback from panel members and from an end of project dissemination event. Benefits, limitations and challenges of the present approach to user involvement and to the design of self-administered communication training programmes are discussed. Conclusion: The project was characterized by two innovative features: the involvement of service users not only at its outset and conclusion but throughout its course; and the exclusive use of naturally occurring conversational speech in the training programme. While both present practical challenges, the project has demonstrated the potential for ecologically valid speech rehabilitation training.
- Published
- 2019
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41. The three A's of colonoscopy referral.
- Author
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Bampton P, Sammour T, Brown GJ, Hewett DG, and Worthley DL
- Subjects
- Australia, Colorectal Neoplasms diagnosis, Hospitals, Private economics, Hospitals, Public economics, Humans, Time Factors, Colonoscopy economics, Referral and Consultation
- Published
- 2018
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42. A corpus of audio-visual Lombard speech with frontal and profile views.
- Author
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Alghamdi N, Maddock S, Marxer R, Barker J, and Brown GJ
- Subjects
- Acoustics, Adolescent, Adult, Female, Humans, Male, Phonetics, Sex Factors, Speech Production Measurement, Video Recording, Young Adult, Adaptation, Psychological, Noise adverse effects, Speech Acoustics, Speech Perception, Visual Perception, Voice Quality
- Abstract
This paper presents a bi-view (front and side) audiovisual Lombard speech corpus, which is freely available for download. It contains 5400 utterances (2700 Lombard and 2700 plain reference utterances), produced by 54 talkers, with each utterance in the dataset following the same sentence format as the audiovisual "Grid" corpus [Cooke, Barker, Cunningham, and Shao (2006). J. Acoust. Soc. Am. 120(5), 2421-2424]. Analysis of this dataset confirms previous research, showing prominent acoustic, phonetic, and articulatory speech modifications in Lombard speech. In addition, gender differences are observed in the size of Lombard effect. Specifically, female talkers exhibit a greater increase in estimated vowel duration and a greater reduction in F2 frequency.
- Published
- 2018
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43. Strain-induced high-temperature perovskite ferromagnetic insulator.
- Author
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Meng D, Guo H, Cui Z, Ma C, Zhao J, Lu J, Xu H, Wang Z, Hu X, Fu Z, Peng R, Guo J, Zhai X, Brown GJ, Knize R, and Lu Y
- Abstract
Ferromagnetic insulators are required for many new magnetic devices, such as dissipationless quantum-spintronic devices, magnetic tunneling junctions, etc. Ferromagnetic insulators with a high Curie temperature and a high-symmetry structure are critical integration with common single-crystalline oxide films or substrates. So far, the commonly used ferromagnetic insulators mostly possess low-symmetry structures associated with a poor growth quality and widespread properties. The few known high-symmetry materials either have extremely low Curie temperatures (≤16 K), or require chemical doping of an otherwise antiferromagnetic matrix. Here we present compelling evidence that the LaCoO
3 single-crystalline thin film under tensile strain is a rare undoped perovskite ferromagnetic insulator with a remarkably high TC of up to 90 K. Both experiments and first-principles calculations demonstrate tensile-strain-induced ferromagnetism which does not exist in bulk LaCoO3 The ferromagnetism is strongest within a nearly stoichiometric structure, disappearing when the Co2+ defect concentration reaches about 10%. Significant impact of the research includes demonstration of a strain-induced high-temperature ferromagnetic insulator, successful elevation of the transition over the liquid-nitrogen temperature, and high potential for integration into large-area device fabrication processes., Competing Interests: The authors declare no conflict of interest., (Copyright © 2018 the Author(s). Published by PNAS.)- Published
- 2018
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44. Risk Stratification for Covert Invasive Cancer Among Patients Referred for Colonic Endoscopic Mucosal Resection: A Large Multicenter Cohort.
- Author
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Burgess NG, Hourigan LF, Zanati SA, Brown GJ, Singh R, Williams SJ, Raftopoulos SC, Ormonde D, Moss A, Byth K, Mahajan H, McLeod D, and Bourke MJ
- Subjects
- Adolescent, Adult, Aged, Aged, 80 and over, Colon, Sigmoid pathology, Colonic Polyps surgery, Colonoscopy, Female, Humans, Male, Middle Aged, Neoplasm Invasiveness, Prospective Studies, Rectum pathology, Risk Assessment, Risk Factors, Young Adult, Colonic Neoplasms pathology, Colonic Polyps classification, Colonic Polyps pathology, Endoscopic Mucosal Resection, Tumor Burden
- Abstract
Background & Aims: Among patients with large colorectal sessile polyps or laterally spreading lesions, it is important to identify those at risk for submucosal invasive cancer (SMIC). Lesions with overt endoscopic evidence of SMIC are referred for surgery, although those without these features might still contain SMIC that is not visible on endoscopic inspection (covert SMIC). Lesions with a high covert SMIC risk might be better suited for endoscopic submucosal dissection than for endoscopic mucosal resection (EMR). We analyzed a group of patients with large colon lesions to identify factors associated with SMIC, and examined lesions without overt endoscopic high-risk signs to determine factors associated with covert SMIC., Methods: We performed a prospective cohort study of consecutive patients referred for EMR of large sessile or flat colorectal polyps or laterally spreading lesions (≥20 mm) at academic hospitals in Australia from September 2008 through September 2016. We collected data on patient and lesion characteristics, outcomes of procedures, and histology findings. We excluded serrated lesions from the analysis of covert SMIC due to their distinct phenotype and biologic features., Results: We analyzed 2277 lesions (mean size, 36.9 mm) from 2106 patients (mean age, 67.7 years; 53.2% male). SMIC was evident in 171 lesions (7.6%). Factors associated with SMIC included Kudo pit pattern V, a depressed component (0-IIc), rectosigmoid location, 0-Is or 0-IIa+Is Paris classification, non-granular surface morphology, and increasing size. After exclusion of lesions that were obviously SMIC or serrated, factors associated with covert SMIC were rectosigmoid location (odds ratio, 1.87; P = .01), combined Paris classification, surface morphology (odds ratios, 3.96-22.5), and increasing size (odds ratio, 1.16/10 mm; P = .012)., Conclusions: In a prospective study of 2106 patients who underwent EMR for large sessile or flat colorectal polyps or laterally spreading lesions, we associated rectosigmoid location, combined Paris classification and surface morphology, and increasing size with increased risk for covert malignancy. Rectosigmoid 0-Is and 0-IIa+Is non-granular lesions have a high risk for malignancy, whereas proximally located 0-Is or 0-IIa granular lesions have a low risk. These findings can be used to inform decisions on which patients should undergo endoscopic submucosal dissection, EMR, or surgery. ClinicalTrials.gov, Number: NCT02000141., (Copyright © 2017 AGA Institute. Published by Elsevier Inc. All rights reserved.)
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- 2017
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45. Acoustically actuated ultra-compact NEMS magnetoelectric antennas.
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Nan T, Lin H, Gao Y, Matyushov A, Yu G, Chen H, Sun N, Wei S, Wang Z, Li M, Wang X, Belkessam A, Guo R, Chen B, Zhou J, Qian Z, Hui Y, Rinaldi M, McConney ME, Howe BM, Hu Z, Jones JG, Brown GJ, and Sun NX
- Abstract
State-of-the-art compact antennas rely on electromagnetic wave resonance, which leads to antenna sizes that are comparable to the electromagnetic wavelength. As a result, antennas typically have a size greater than one-tenth of the wavelength, and further miniaturization of antennas has been an open challenge for decades. Here we report on acoustically actuated nanomechanical magnetoelectric (ME) antennas with a suspended ferromagnetic/piezoelectric thin-film heterostructure. These ME antennas receive and transmit electromagnetic waves through the ME effect at their acoustic resonance frequencies. The bulk acoustic waves in ME antennas stimulate magnetization oscillations of the ferromagnetic thin film, which results in the radiation of electromagnetic waves. Vice versa, these antennas sense the magnetic fields of electromagnetic waves, giving a piezoelectric voltage output. The ME antennas (with sizes as small as one-thousandth of a wavelength) demonstrates 1-2 orders of magnitude miniaturization over state-of-the-art compact antennas without performance degradation. These ME antennas have potential implications for portable wireless communication systems.The miniaturization of antennas beyond a wavelength is limited by designs which rely on electromagnetic resonances. Here, Nan et al. have developed acoustically actuated antennas that couple the acoustic resonance of the antenna with the electromagnetic wave, reducing the antenna footprint by up to 100.
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- 2017
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46. Endoscopic mucosal resection for large serrated lesions in comparison with adenomas: a prospective multicentre study of 2000 lesions.
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Pellise M, Burgess NG, Tutticci N, Hourigan LF, Zanati SA, Brown GJ, Singh R, Williams SJ, Raftopoulos SC, Ormonde D, Moss A, Byth K, P'Ng H, Mahajan H, McLeod D, and Bourke MJ
- Subjects
- Adenoma pathology, Aftercare, Age Factors, Aged, Colonic Polyps pathology, Colonoscopy, Colorectal Neoplasms pathology, Female, Humans, Male, Middle Aged, Neoplasm, Residual, Prospective Studies, Treatment Failure, Tumor Burden, Adenoma surgery, Blood Loss, Surgical, Colonic Polyps surgery, Colorectal Neoplasms surgery, Endoscopic Mucosal Resection adverse effects, Intestinal Perforation etiology, Neoplasm Recurrence, Local pathology, Postoperative Hemorrhage etiology
- Abstract
Objective: Endoscopic mucosal resection (EMR) is effective for large laterally spreading flat and sessile lesions (LSLs). Sessile serrated adenomas/polyps (SSA/Ps) are linked to the relative failure of colonoscopy to prevent proximal colorectal cancer. We aimed to examine the technical success, adverse events and recurrence following EMR for large SSA/Ps in comparison with large conventional adenomas., Design: Over 74 months till August 2014, prospective multicentre data of LSLs ≥20 mm were analysed. A standardised dye-based conventional EMR technique followed by scheduled surveillance colonoscopy was used., Results: From a total of 2000 lesions, 323 SSA/Ps in 246 patients and 1527 adenomas in 1425 patients were included for analysis. Technical success for EMR was superior in SSA/Ps compared with adenomas (99.1% vs 94.5%, p<0.001). Significant bleeding and perforation were similar in both cohorts. The cumulative recurrence rates for adenomas after 6, 12, 18 and 24 months were 16.1%, 20.4%, 23.4% and 28.4%, respectively. For SSA/Ps, they were 6.3% at 6 months and 7.0% from 12 months onwards (p<0.001). Following multivariable adjustment, the HR of recurrence for adenomas versus SSA/Ps was 1.7 (95% CI 0.9 to 3.0, p=0.097). Subgroup analysis by lesion size revealed an eightfold increased risk of recurrence for 20-25 mm adenomas versus SSA/Ps, but no significantly different risk between lesion types in larger lesion groups., Conclusion: Recurrence after EMR of 20-25 mm LSLs is significantly less frequent in SSA/Ps compared with adenomatous lesions. SSA/Ps can be more effectively removed than adenomatous LSLs with equivalent safety. Ensuring complete initial resection is imperative for avoiding recurrence., Trial Registration Number: ClinicalTrials.gov NCT01368289., (Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.)
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- 2017
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47. Non-Volatile Ferroelectric Switching of Ferromagnetic Resonance in NiFe/PLZT Multiferroic Thin Film Heterostructures.
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Hu Z, Wang X, Nan T, Zhou Z, Ma B, Chen X, Jones JG, Howe BM, Brown GJ, Gao Y, Lin H, Wang Z, Guo R, Chen S, Shi X, Shi W, Sun H, Budil D, Liu M, and Sun NX
- Abstract
Magnetoelectric effect, arising from the interfacial coupling between magnetic and electrical order parameters, has recently emerged as a robust means to electrically manipulate the magnetic properties in multiferroic heterostructures. Challenge remains as finding an energy efficient way to modify the distinct magnetic states in a reliable, reversible, and non-volatile manner. Here we report ferroelectric switching of ferromagnetic resonance in multiferroic bilayers consisting of ultrathin ferromagnetic NiFe and ferroelectric Pb0.92La0.08Zr0.52Ti0.48O3 (PLZT) films, where the magnetic anisotropy of NiFe can be electrically modified by low voltages. Ferromagnetic resonance measurements confirm that the interfacial charge-mediated magnetoelectric effect is dominant in NiFe/PLZT heterostructures. Non-volatile modification of ferromagnetic resonance field is demonstrated by applying voltage pulses. The ferroelectric switching of magnetic anisotropy exhibits extensive applications in energy-efficient electronic devices such as magnetoelectric random access memories, magnetic field sensors, and tunable radio frequency (RF)/microwave devices.
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- 2016
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48. Prediction of Clinically Significant Bleeding Following Wide-Field Endoscopic Resection of Large Sessile and Laterally Spreading Colorectal Lesions: A Clinical Risk Score.
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Bahin FF, Rasouli KN, Byth K, Hourigan LF, Singh R, Brown GJ, Zanati SA, Moss A, Raftopoulos S, Williams SJ, and Bourke MJ
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- Adenoma pathology, Aged, Australia epidemiology, Embolization, Therapeutic, Female, Gastrointestinal Hemorrhage therapy, Hospitalization, Humans, Length of Stay, Logistic Models, Male, Middle Aged, Odds Ratio, Postoperative Hemorrhage therapy, Reoperation, Risk Assessment, Adenoma surgery, Colonoscopy, Colorectal Neoplasms surgery, Endoscopic Mucosal Resection, Gastrointestinal Hemorrhage epidemiology, Postoperative Hemorrhage epidemiology
- Abstract
Objectives: Clinically significant bleeding (CSPEB) is the most frequent adverse event following wide-field endoscopic mucosal resection (WF-EMR) of large sessile and laterally spreading colorectal lesions (LSL). There is limited knowledge regarding accurate prediction of CSPEB. We aimed to derive a score to predict the risk of CSPEB., Methods: Data on patient and lesion characteristics and outcomes from WF-EMRs of LSL ≥20 mm at 8 referral hospitals were analyzed. The cohort was divided at random into equal sized training and test groups. Independent predictors of CSPEB in the training cohort were identified by multiple logistic regression analysis and used to develop a risk score. The performance of this score was assessed in the independent test cohort., Results: Over 80 months to June 2015, 2,128 patients with 2,424 LSL were referred for WF-EMR. Two thousand and twelve patients were eligible for analysis. There were 135 cases of CSPEB (6.7%). In the training cohort of 1,006 patients, the independent predictors of CSPEB were lesion size >30 mm (odds ratio (OR) 2.5), proximal colonic location (OR 2.3), presence of a major comorbidity (OR 1.5), and epinephrine in injection solution (OR 0.57). The derived risk score comprised lesion size >30 mm (2 points), proximal colon (2 points), presence of major comorbidity (1 point), and absence of epinephrine use (1 point). The probabilities of CSPEB for scores of 0, 1, 2, 3, 4, and ≥5 in the training cohort were 1.5, 2.0, 5.6, 7.8, 9.1, and 17.5% and were 0.9, 6.7, 4.9, 6.2, 9.0, and 15.7% in the test cohort. The probabilities of CSPEB in those with low (score 0-1), medium (score 2-4), and elevated (score 5-6) risk levels were 1.7, 7.1, and 17.5% in the training cohort and 3.4, 6.2, and 15.7% in the test cohort., Conclusions: Patients at elevated risk of CSPEB can be identified using four readily available variables. This knowledge may improve the management of those undergoing WF-EMR and assist in designing studies evaluating CSPEB.
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- 2016
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49. Two-Dimensional Nanoparticle Cluster Formation in Supercritical Fluid CO2.
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Wang JS, Wai CM, Brown GJ, and Apt SD
- Abstract
Supercritical fluid carbon dioxide (sc-CO2) is capable of depositing nanoparticles in small structures of silicon substrates because of its gas-like penetration, liquid-like solvation abilities, and near-zero surface tension. In nanometer-sized shallow wells on silicon surface, formation of two-dimensional (2D) monolayer metal nanoparticle (NP) clusters can be achieved using the sc-CO2 deposition method. Nanoparticles tend to fill nanostructured holes first, and then, if sufficient nanoparticles are available, they will continue to cover the flat areas nearby, unless defects or other surface imperfections are available. In addition, SEM images of two-dimensional gold (Au) nanoparticle clusters formed on a flat silicon surface with two to a dozen or more of the nanoparticles are provided to illustrate the patterns of nanoparticle cluster formation in sc-CO2.
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- 2016
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50. Clinical and endoscopic predictors of cytological dysplasia or cancer in a prospective multicentre study of large sessile serrated adenomas/polyps.
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Burgess NG, Pellise M, Nanda KS, Hourigan LF, Zanati SA, Brown GJ, Singh R, Williams SJ, Raftopoulos SC, Ormonde D, Moss A, Byth K, P'Ng H, McLeod D, and Bourke MJ
- Subjects
- Adenoma diagnosis, Adult, Aged, Aged, 80 and over, Colonic Polyps diagnosis, Colorectal Neoplasms diagnosis, Decision Support Techniques, Female, Humans, Logistic Models, Male, Middle Aged, Prospective Studies, Adenoma pathology, Colonic Polyps pathology, Colonoscopy, Colorectal Neoplasms pathology
- Abstract
Objective: The serrated neoplasia pathway accounts for up to 30% of all sporadic colorectal cancers (CRCs). Sessile serrated adenomas/polyps (SSA/Ps) with cytological dysplasia (SSA/P-D) are a high-risk serrated CRC precursor with little existing data. We aimed to describe the clinical and endoscopic predictors of SSA/P-D and high grade dysplasia (HGD) or cancer., Design: Prospective multicentre data of SSA/Ps ≥20 mm referred for treatment by endoscopic mucosal resection (September 2008-July 2013) were analysed. Imaging and lesion assessment was standardised. Histological findings were correlated with clinical and endoscopic findings., Results: 268 SSA/Ps were found in 207/1546 patients (13.4%). SSA/P-D comprised 32.4% of SSA/Ps ≥20 mm. Cancer occurred in 3.9%. On multivariable analysis, SSA/P-D was associated with increasing age (OR=1.69 per decade; 95% CI (1.19 to 2.40), p0.004) and increasing lesion size (OR=1.90 per 10 mm; 95% CI (1.30 to 2.78), p0.001), an 'adenomatous' pit pattern (Kudo III, IV or V) (OR=3.98; 95% CI (1.94 to 8.15), p<0.001) and any 0-Is component within a SSA/P (OR=3.10; 95% CI (1.19 to 8.12) p0.021). Conventional type dysplasia was more likely to exhibit an adenomatous pit pattern than serrated dysplasia. HGD or cancer was present in 7.2% and on multivariable analysis, was associated with increasing age (OR=2.0 per decade; 95% CI 1.13 to 3.56) p0.017) and any Paris 0-Is component (OR=10.2; 95% CI 3.18 to 32.4, p<0.001)., Conclusions: Simple assessment tools allow endoscopists to predict SSA/P-D or HGD/cancer in SSA/Ps ≥20 mm. Correct prediction is limited by failure to recognise SSA/P-D which may mimic conventional adenoma. Understanding the concept of SSA/P-D and the pitfalls of SSA/P assessment may improve detection, recognition and resection and potentially reduce interval cancer., Trial Registration Number: NCT01368289., (Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/)
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- 2016
- Full Text
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