1,813 results on '"D. Ziegler"'
Search Results
52. Substrate Roughness and Tilt Angle Dependence of Sum-Frequency Generation Odd–Even Effects in Self-Assembled Monolayers
- Author
-
Chuanshen Du, Richard S. Andino, Matthew C. Rotondaro, Shane W. Devlin, Shyamsunder Erramilli, Lawrence D. Ziegler, and Martin M. Thuo
- Subjects
General Energy ,Physical and Theoretical Chemistry ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials - Published
- 2022
- Full Text
- View/download PDF
53. Healthcare utilization and clinical outcomes after ablation of atrial fibrillation in patients with and without insertable cardiac monitoring
- Author
-
Moussa C, Mansour, Emily M, Gillen, Audrey, Garman, Sarah C, Rosemas, Noreli, Franco, Paul D, Ziegler, and Jesse M, Pines
- Abstract
Compared with short-term electrocardiogram (ECG) monitors, insertable cardiac monitors (ICMs) have been shown to increase atrial fibrillation (AF) detection rates and the opportunity to treat recurrent AF in patients postablation.To examine healthcare utilization and clinical outcomes following AF ablation, in patients with vs without ICM.Retrospective analysis pooling Optum Clinformatics and Medicare Fee-for-service 5% Sample claims databases. Patients with an AF ablation between January 1, 2011, and March 31, 2018 who received an ICM implant within 1 year pre-/postablation were propensity score matched 1:3 to patients without ICM. Outcomes included AF-related healthcare utilization, medication use, and occurrence of composite severe cardiovascular events (stroke / transient ischemic attack, major bleeds, systemic embolism, AF- or heart failure-related hospitalization, or death).A total of 1000 ICM patients and 2998 non-ICM patients were included. During mean follow-up of 33 ± 16 months postablation, ICM patients experienced significantly fewer severe cardiovascular events (1.09 ± 2.22 vs 1.37 ± 4.19,A shift from acute, reactive care to routine outpatient management was observed in patients with long-term ECG monitoring. Results suggest closer patient management in patients with long-term monitoring after an AF ablation and an improvement in outcomes, at similar overall cost.
- Published
- 2022
- Full Text
- View/download PDF
54. Mobile Trions in Electrically Tunable 2D Hybrid Perovskites
- Author
-
Jonas D. Ziegler, Yeongsu Cho, Sophia Terres, Matan Menahem, Takashi Taniguchi, Kenji Watanabe, Omer Yaffe, Timothy C. Berkelbach, and Alexey Chernikov
- Subjects
Mechanics of Materials ,Mechanical Engineering ,General Materials Science - Published
- 2023
- Full Text
- View/download PDF
55. Energy production and water savings from floating solar photovoltaics on global reservoirs
- Author
-
Yubin Jin, Shijie Hu, Alan D. Ziegler, Luke Gibson, J. Elliott Campbell, Rongrong Xu, Deliang Chen, Kai Zhu, Yan Zheng, Bin Ye, Fan Ye, and Zhenzhong Zeng
- Subjects
Urban Studies ,Global and Planetary Change ,Ecology ,Renewable Energy, Sustainability and the Environment ,Geography, Planning and Development ,Management, Monitoring, Policy and Law ,Nature and Landscape Conservation ,Food Science - Published
- 2023
- Full Text
- View/download PDF
56. Learning to Prognostically Forage in a Neural Network Model of the Interactions between Neuromodulators and Prefrontal Cortex.
- Author
-
Suhas E. Chelian, Matthias D. Ziegler, Peter Pirolli, and Rajan Bhattacharyya
- Published
- 2014
- Full Text
- View/download PDF
57. Postablation Atrial Fibrillation Burden and Patient Activity Level: Insights From the DISCERN AF Study
- Author
-
Riccardo Proietti, David Birnie, Paul D. Ziegler, George A. Wells, and Atul Verma
- Subjects
ablation ,Atrial Fibrillation Burden ,atrial fibrillation ,exercise ,physical exercise ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Background Recent evidence shows an association between the level of physical activity and cardiovascular mortality and morbidity in patients with atrial fibrillation (AF). We sought to assess the impact of AF daily burden on the activity level of the patient who underwent pulmonary vein isolation. Methods and Results Patients enrolled in the DISCERN AF (Discerning Symptomatic and Asymptomatic Episodes Pre and Post Radiofrequency Ablation of Atrial Fibrillation) study all had insertable cardiac monitors, which provided the daily burden of atrial tachycardia and atrial fibrillation (AT/AF) and a corresponding activity level. A total of 44 341 daily AT/AF burden points were collected from 50 patients with an average of 887 observations for every patient, with
- Published
- 2018
- Full Text
- View/download PDF
58. Sulforaphane Inhibits Inflammatory Responses of Primary Human T-Cells by Increasing ROS and Depleting Glutathione
- Author
-
Jie Liang, Beate Jahraus, Emre Balta, Jacqueline D. Ziegler, Katrin Hübner, Norbert Blank, Beate Niesler, Guido H. Wabnitz, and Yvonne Samstag
- Subjects
sulforaphane ,primary human T-cells ,reactive oxygen species ,glutathione ,TH17 ,rheumatoid arthritis ,Immunologic diseases. Allergy ,RC581-607 - Abstract
The activity and function of T-cells are influenced by the intra- and extracellular redox milieu. Oxidative stress induces hypo responsiveness of untransformed T-cells. Vice versa increased glutathione (GSH) levels or decreased levels of reactive oxygen species (ROS) prime T-cell metabolism for inflammation, e.g., in rheumatoid arthritis. Therefore, balancing the T-cell redox milieu may represent a promising new option for therapeutic immune modulation. Here we show that sulforaphane (SFN), a compound derived from plants of the Brassicaceae family, e.g., broccoli, induces a pro-oxidative state in untransformed human T-cells of healthy donors or RA patients. This manifested as an increase of intracellular ROS and a marked decrease of GSH. Consistently, increased global cysteine sulfenylation was detected. Importantly, a major target for SFN-mediated protein oxidation was STAT3, a transcription factor involved in the regulation of TH17-related genes. Accordingly, SFN significantly inhibited the activation of untransformed human T-cells derived from healthy donors or RA patients, and downregulated the expression of the transcription factor RORγt, and the TH17-related cytokines IL-17A, IL-17F, and IL-22, which play a major role within the pathophysiology of many chronic inflammatory/autoimmune diseases. The inhibitory effects of SFN could be abolished by exogenously supplied GSH and by the GSH replenishing antioxidant N-acetylcysteine (NAC). Together, our study provides mechanistic insights into the mode of action of the natural substance SFN. It specifically exerts TH17 prone immunosuppressive effects on untransformed human T-cells by decreasing GSH and accumulation of ROS. Thus, SFN may offer novel clinical options for the treatment of TH17 related chronic inflammatory/autoimmune diseases such as rheumatoid arthritis.
- Published
- 2018
- Full Text
- View/download PDF
59. Interlayer excitons in MoSe2/2D perovskite hybrid heterostructures – the interplay between charge and energy transfer
- Author
-
M. Karpińska, J. Jasiński, R. Kempt, J. D. Ziegler, H. Sansom, T. Taniguchi, K. Watanabe, H. J. Snaith, A. Surrente, M. Dyksik, D. K. Maude, Ł. Kłopotowski, A. Chernikov, A. Kuc, M. Baranowski, P. Plochocka, Laboratoire national des champs magnétiques intenses - Grenoble (LNCMI-G ), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA), Laboratoire national des champs magnétiques intenses - Toulouse (LNCMI-T), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA), Polish Academy of Sciences (PAN), Wroclaw University of Science and Technology, Technische Universität Dresden = Dresden University of Technology (TU Dresden), Fakultät für Physik [Regensburg], Universität Regensburg (UR), Clarendon Laboratory [Oxford], University of Oxford, Université de Tsukuba = University of Tsukuba, University of Regensburg, Universität Leipzig, and ANR-17-EURE-0009,NanoX,Science et Ingénierie à l'Echelle Nano(2017)
- Subjects
Condensed Matter::Materials Science ,transition metal dichalcogenides ,General Materials Science ,[PHYS.PHYS.PHYS-CHEM-PH]Physics [physics]/Physics [physics]/Chemical Physics [physics.chem-ph] ,[CHIM.MATE]Chemical Sciences/Material chemistry ,Metal halide perovskites ,Metal halide perovskites, transition metal dichalcogenides, 2D perovskites/transition metal dichalcogenide heterostructures ,Condensed Matter::Mesoscopic Systems and Quantum Hall Effect ,Computer Science::Distributed, Parallel, and Cluster Computing ,2D perovskites/transition metal dichalcogenide heterostructures - Abstract
Van der Waals crystals have opened a new and exciting chapter in heterostructure research, removing lattice matching constraints characteristic of epitaxial semiconductors. They provide unprecedented flexibility for heterostructure design. Combining 2D perovskites with other 2D materials, in particular transition metal dichalcogenides (TMDs) has recently emerged as an intriguing way to design hybrid opto- electronic devices. However, the excitation transfer mechanism between the layers (charge or energy transfer) remains to be elucidated. Here we investigate PEA2PbI4/MoSe2 and (BA)2PbI4/MoSe2 heterostructures by combining optical spectroscopy and density functional theory (DFT) calculations. We show that the band alignment facilitates charge transfer. Namely, holes are transferred from the TMD to the 2D perovskite, while the electron transfer is blocked, resulting in the formation of inter-layer excitons. Moreover, we show that the energy transfer mechanism can be turned on by an appropriate alignment of the excitonic states, providing a rule of thumb for the deterministic control of the excitation transfer mechanism in TMD/2D-perovskite heterostructures.
- Published
- 2022
- Full Text
- View/download PDF
60. Stronger winds increase the sand-dust storm risk in northern China
- Author
-
Yi Liu, Rongrong Xu, Alan D. Ziegler, and Zhenzhong Zeng
- Subjects
Chemistry (miscellaneous) ,Environmental Chemistry ,Pollution ,Analytical Chemistry - Abstract
Annual average wind speed and sand-dust storm frequency trends in China changed synchronously.
- Published
- 2022
- Full Text
- View/download PDF
61. Environmental change since the Last Glacial Maximum: palaeo‐evidence from the Nee Soon Freshwater Swamp Forest, Singapore
- Author
-
Canh Tien Trinh Nguyen, Patrick Moss, Robert J. Wasson, Philip Stewart, and Alan D. Ziegler
- Subjects
Arts and Humanities (miscellaneous) ,Earth and Planetary Sciences (miscellaneous) ,Paleontology - Published
- 2021
- Full Text
- View/download PDF
62. Boundary exchange completes the marine Pb cycle jigsaw
- Author
-
Mengli Chen, Gonzalo Carrasco, Ning Zhao, Xianfeng Wang, Jen Nie Lee, Jani T. I. Tanzil, Kogila Vani Annammala, Seng Chee Poh, Federico M. Lauro, Alan D. Ziegler, Decha Duangnamon, and Edward A. Boyle
- Subjects
Multidisciplinary - Abstract
Material fluxes at the land–ocean interface impact seawater composition and global cycling of elements. However, most attention has been focused on the fluvial dissolved fluxes. For elements like lead (Pb), whose fluvial particulate flux into the ocean is two orders of magnitude higher than the dissolved counterpart, the role of particulates in elemental cycling is potentially important but currently less appreciated. Using both chemical analyses on samples collected from around equatorial Southeast Asia and model simulations, we show that particulate-dissolved exchange is an important mechanism controlling the concentration and isotopic composition of dissolved Pb in the ocean. Our model indicates that Pb contributed from particulate-dissolved exchange at ocean boundaries is larger than, or at least comparable to, other major Pb sources to the seawater before the Anthropocene, when the anthropogenic Pb was absent. Our work highlights the importance of boundary exchange in understanding marine element cycling and weathering-climate feedback.
- Published
- 2023
- Full Text
- View/download PDF
63. Cost-effectiveness of an insertable cardiac monitor in a high-risk population in the US
- Author
-
K K Witte, David Lanctin, Stelios I Tsintzos, L. Sawyer, Claudia Rinciog, Scott E. Kasner, Matthew R. Reynolds, Sarah C Rosemas, Mitchell Elkind, Paul D. Ziegler, and Frank Jones
- Subjects
medicine.medical_specialty ,education.field_of_study ,Cost–benefit analysis ,business.industry ,Cost effectiveness ,Population ,Atrial fibrillation ,Hemorrhagic strokes ,medicine.disease ,Health outcomes ,Emergency medicine ,medicine ,In patient ,education ,business ,Cardiology and Cardiovascular Medicine ,Stroke ,health care economics and organizations - Abstract
Background Insertable cardiac monitors (ICMs) are a clinically effective means of detecting atrial fibrillation (AF) in high-risk patients, and guiding the initiation of non-vitamin K oral anticoagulants (NOACs). Their cost-effectiveness from a US clinical payer perspective is not yet known. The objective of this study was to evaluate the cost-effectiveness of ICMs compared to standard of care (SoC) for detecting AF in patients at high risk of stroke (CHADS2 ≥ 2), in the US. Methods Using patient data from the REVEAL AF trial (n = 393, average CHADS2 score = 2.9), a Markov model estimated the lifetime costs and benefits of detecting AF with an ICM or with SoC (specifically intermittent use of electrocardiograms and 24-h Holter monitors). Ischemic and hemorrhagic strokes, intra- and extra-cranial hemorrhages, and minor bleeds were modelled. Diagnostic and device costs, costs of treating stroke and bleeding events and medical therapy—specifically costs of NOACs were included. Costs and health outcomes, measured as quality-adjusted life years (QALYs), were discounted at 3% per annum, in line with standard practice in the US setting. One-way deterministic and probabilistic sensitivity analyses (PSA) were undertaken. Results Lifetime per-patient cost for ICM was $31,116 versus $25,330 for SoC. ICMs generated a total of 7.75 QALYs versus 7.59 for SoC, with 34 fewer strokes projected per 1000 patients. The model estimates a number needed to treat of 29 per stroke avoided. The incremental cost-effectiveness ratio was $35,528 per QALY gained. ICMs were cost-effective in 75% of PSA simulations, using a $50,000 per QALY threshold, and a 100% probability of being cost-effective at a WTP threshold of $150,000 per QALY. Conclusions The use of ICMs to identify AF in a high-risk population is likely to be cost-effective in the US healthcare setting.
- Published
- 2023
- Full Text
- View/download PDF
64. Root zone soil moisture estimation by Terra/MODIS imagery over the tropical catchment in northern Thailand.
- Author
-
Tzu-Yin Chang, Yuei-An Liou, Yi-Chen Wang, and Alan D. Ziegler
- Published
- 2011
- Full Text
- View/download PDF
65. Predictors of Atrial Fibrillation in Patients With Stroke Attributed to Large- or Small-Vessel Disease: A Prespecified Secondary Analysis of the STROKE AF Randomized Clinical Trial
- Author
-
Lee H, Schwamm, Hooman, Kamel, Christopher B, Granger, Jonathan P, Piccini, Jeffrey M, Katz, Pramod P, Sethi, Evgeny V, Sidorov, Scott E, Kasner, Scott B, Silverman, Theodore T, Merriam, Noreli, Franco, Paul D, Ziegler, Richard A, Bernstein, and Richard, Zweifler
- Abstract
The Stroke of Known Cause and Underlying Atrial Fibrillation (STROKE AF) trial found that approximately 1 in 8 patients with recent ischemic stroke attributed to large- or small-vessel disease had poststroke atrial fibrillation (AF) detected by an insertable cardiac monitor (ICM) at 12 months. Identifying predictors of AF could be useful when considering an ICM in routine poststroke clinical care.To determine the association between commonly assessed risk factors and poststroke detection of new AF in the STROKE AF cohort monitored by ICM.This was a prespecified analysis of a randomized (1:1) clinical trial that enrolled patients between April 1, 2016, and July 12, 2019, with primary follow-up through 2020 and mean (SD) duration of 11.0 (3.0) months. Eligible patients were selected from 33 clinical research sites in the US. Patients had an index stroke attributed to large- or small-vessel disease and were 60 years or older or aged 50 to 59 years with at least 1 additional stroke risk factor. A total of 496 patients were enrolled, and 492 were randomly assigned to study groups (3 did not meet inclusion criteria, and 1 withdrew consent). Patients in the ICM group had the index stroke within 10 days before insertion. Data were analyzed from October 8, 2021, to January 28, 2022.ICM monitoring vs site-specific usual care (short-duration external cardiac monitoring).The ICM device automatically detects AF episodes 2 or more minutes in length; episodes were adjudicated by an expert committee. Cox regression multivariable modeling included all parameters identified in the univariate analysis having P values.10. AF detection rates were calculated using Kaplan-Meier survival estimates.The analysis included the 242 participants randomly assigned to the ICM group in the STROKE AF study. Among 242 patients monitored with ICM, 27 developed AF (mean [SD] age, 66.6 [9.3] years; 144 men [60.0%]; 96 [40.0%] women). Two patients had missing baseline data and exited the study early. Univariate predictors of AF detection included age (per 1-year increments: hazard ratio [HR], 1.05; 95% CI, 1.01-1.09; P = .02), CHA2DS2-VASc score (per point: HR, 1.54; 95% CI, 1.15-2.06; P = .004), chronic obstructive pulmonary disease (HR, 2.49; 95% CI, 0.86-7.20; P = .09), congestive heart failure (CHF; with preserved or reduced ejection fraction: HR, 6.64; 95% CI, 2.29-19.24; P .001), left atrial enlargement (LAE; HR, 3.63; 95% CI, 1.55-8.47; P = .003), QRS duration (HR, 1.02; 95% CI, 1.00-1.04; P = .04), and kidney dysfunction (HR, 3.58; 95% CI, 1.35-9.46; P = .01). In multivariable modeling (n = 197), only CHF (HR, 5.06; 95% CI, 1.45-17.64; P = .05) and LAE (HR, 3.32; 1.34-8.19; P = .009) remained significant predictors of AF. At 12 months, patients with CHF and/or LAE (40 of 142 patients) had an AF detection rate of 23.4% vs 5.0% for patients with neither (HR, 5.1; 95% CI, 2.0-12.8; P .001).Among patients with ischemic stroke attributed to large- or small-vessel disease, CHF and LAE were associated with a significantly increased risk of poststroke AF detection. These patients may benefit most from the use of ICMs as part of a secondary stroke prevention strategy. However, the study was not powered for clinical predictors of AF, and therefore, other clinical characteristics may not have reached statistical significance.ClinicalTrials.gov Identifier: NCT02700945.
- Published
- 2022
66. Ultrafast 2DIR comparison of rotational energy transfer, isolated binary collision breakdown, and near critical fluctuations in Xe and SF
- Author
-
Matthew C, Rotondaro, Arkash, Jain, Shyamsunder, Erramilli, and Lawrence D, Ziegler
- Abstract
The density dependence of rotational and vibrational energy relaxation (RER and VER) of the N
- Published
- 2022
67. A call for reducing tourism risk to environmental hazards in the Himalaya
- Author
-
G. Sasges, C. E. Ong, M. Apollo, Pradeep Srivastava, Robert J. Wasson, Brian G. McAdoo, S. K. Nepal, D. Bishwokarma, Alan D. Ziegler, Sorain J. Ramchunder, Alok Bhardwaj, Y. P. Sundriyal, and Jamie Gillen
- Subjects
Global and Planetary Change ,Safeguard ,Sociology and Political Science ,business.industry ,Geography, Planning and Development ,Climate change ,Business ,Overcrowding ,Development ,Environmental planning ,Risk management ,Tourism ,General Environmental Science - Abstract
As mountain tourism rapidly expands in remote landscapes, there is a critical need for improved disaster risk management to ensure the safety of tourists and industry workers, safeguard infrastruct...
- Published
- 2021
- Full Text
- View/download PDF
68. Narrow-band high-lying excitons with negative-mass electrons in monolayer WSe2
- Author
-
Steven G. Louie, John M. Lupton, Jaroslav Fabian, Alexey Chernikov, Nicola Paradiso, Bartomeu Monserrat, Bo Peng, Sebastian Bange, Jonas Zipfel, Jonas D. Ziegler, Kenji Watanabe, Kai-Qiang Lin, Christian Bäuml, Paulo E. Faria Junior, Christoph Strunk, Takashi Taniguchi, Diana Y. Qiu, Chin Shen Ong, Lin, Kai-Qiang [0000-0001-9609-749X], Ong, Chin Shen [0000-0001-8747-1849], Bange, Sebastian [0000-0002-5850-264X], Peng, Bo [0000-0001-6406-663X], Watanabe, Kenji [0000-0003-3701-8119], Taniguchi, Takashi [0000-0002-1467-3105], Monserrat, Bartomeu [0000-0002-4233-4071], Fabian, Jaroslav [0000-0002-3009-4525], Chernikov, Alexey [0000-0002-9213-2777], Louie, Steven G [0000-0003-0622-0170], Lupton, John M [0000-0002-7899-7598], and Apollo - University of Cambridge Repository
- Subjects
Physics ,Multidisciplinary ,Annihilation ,Photoluminescence ,Phonon ,Exciton ,Science ,ddc:530 ,Ab initio ,General Physics and Astronomy ,General Chemistry ,Electron ,5104 Condensed Matter Physics ,530 Physik ,Condensed Matter::Mesoscopic Systems and Quantum Hall Effect ,Molecular physics ,General Biochemistry, Genetics and Molecular Biology ,Condensed Matter::Materials Science ,Monolayer ,51 Physical Sciences ,Excitation - Abstract
Monolayer transition-metal dichalcogenides (TMDCs) show a wealth of exciton physics. Here, we report the existence of a new excitonic species, the high-lying exciton (HX), in single-layer WSe2 with an energy of ~3.4 eV, almost twice the band-edge A-exciton energy, with a linewidth as narrow as 5.8 meV. The HX is populated through momentum-selective optical excitation in the K-valleys and is identified in upconverted photoluminescence (UPL) in the UV spectral region. Strong electron-phonon coupling results in a cascaded phonon progression with equidistant peaks in the luminescence spectrum, resolvable to ninth order. Ab initio GW-BSE calculations with full electron-hole correlations explain HX formation and unmask the admixture of upper conduction-band states to this complex many-body excitation. These calculations suggest that the HX is comprised of electrons of negative mass. The coincidence of such high-lying excitonic species at around twice the energy of band-edge excitons rationalizes the excitonic quantum-interference phenomenon recently discovered in optical second-harmonic generation (SHG) and explains the efficient Auger-like annihilation of band-edge excitons.
- Published
- 2021
69. Rapid and large-scale mapping of flood inundation via integrating spaceborne synthetic aperture radar imagery with unsupervised deep learning
- Author
-
Lian Feng, Jie Yin, Ganquan Mao, Zhenzhong Zeng, Dalei Hao, Eric F. Wood, Chiyuan Miao, Peirong Lin, Alan D. Ziegler, Junyu Zou, Xin Jiang, Ming Pan, Shijing Liang, Dashan Wang, Xinyue He, and Yelu Zeng
- Subjects
Synthetic aperture radar ,010504 meteorology & atmospheric sciences ,Flood myth ,Computer science ,business.industry ,Deep learning ,0211 other engineering and technologies ,02 engineering and technology ,Land cover ,01 natural sciences ,Atomic and Molecular Physics, and Optics ,Computer Science Applications ,Statistical classification ,Unsupervised learning ,Satellite imagery ,Artificial intelligence ,Computers in Earth Sciences ,business ,Scale (map) ,Engineering (miscellaneous) ,021101 geological & geomatics engineering ,0105 earth and related environmental sciences ,Remote sensing - Abstract
Synthetic aperture radar (SAR) has great potential for timely monitoring of flood information as it penetrates the clouds during flood events. Moreover, the proliferation of SAR satellites with high spatial and temporal resolution provides a tremendous opportunity to understand the flood risk and its quick response. However, traditional algorithms to extract flood inundation using SAR often require manual parameter tuning or data annotation, which presents a challenge for the rapid automated mapping of large and complex flooded scenarios. To address this issue, we proposed a segmentation algorithm for automatic flood mapping in near-real-time over vast areas and for all-weather conditions by integrating Sentinel-1 SAR imagery with an unsupervised machine learning approach named Felz-CNN. The algorithm consists of three phases: (i) super-pixel generation; (ii) convolutional neural network-based featurization; (iii) super-pixel aggregation. We evaluated the Felz-CNN algorithm by mapping flood inundation during the Yangtze River flood in 2020, covering a total study area of 1,140,300 km2. When validated on fine-resolution Planet satellite imagery, the algorithm accurately identified flood extent with producer and user accuracy of 93% and 94%, respectively. The results are indicative of the usefulness of our unsupervised approach for the application of flood mapping. Meanwhile, we overlapped the post-disaster inundation map with a 10-m resolution global land cover map (FROM-GLC10) to assess the damages to different land cover types. Of these types, cropland and residential settlements were most severely affected, with inundation areas of 9,430.36 km2 and 1,397.50 km2, respectively, results that are in agreement with statistics from relevant agencies. Compared with traditional supervised classification algorithms that require time-consuming data annotation, our unsupervised algorithm can be deployed directly to high-performance computing platforms such as Google Earth Engine and PIE-Engine to generate a large-spatial map of flood-affected areas within minutes, without time-consuming data downloading and processing. Importantly, this efficiency enables the fast and effective monitoring of flood conditions to aid in disaster governance and mitigation globally.
- Published
- 2021
- Full Text
- View/download PDF
70. Opportunities for Protecting and Restoring Tropical Coastal Ecosystems by Utilizing a Physical Connectivity Approach
- Author
-
Lucy G. Gillis, Clive G. Jones, Alan D. Ziegler, Daphne van der Wal, Annette Breckwoldt, and Tjeerd J. Bouma
- Subjects
facilitation ,ecosystem engineers ,mangrove forests ,seagrass beds ,coral reefs ,monitoring ,Science ,General. Including nature conservation, geographical distribution ,QH1-199.5 - Abstract
Effectively managing human pressures on tropical seascapes (mangrove forests, seagrass beds, and coral reefs) requires innovative approaches that go beyond the ecosystem as the focal unit. Recent advances in scientific understanding of long-distance connectivity via extended ecosystem engineering effects and on-going rapid developments in monitoring and data-sharing technologies provide viable tools for novel management approaches that use positive across-ecosystem interactions (for example, hydrodynamics). Scientists and managers can now use this collective knowledge to develop monitoring and restoration protocols that are specialized for cross ecosystem fluxes (waves, sediments, nutrients) on a site-specific basis for connected tropical seascape (mangrove forests, seagrass beds, and coral reefs).
- Published
- 2017
- Full Text
- View/download PDF
71. Nonlinear optics in germanium mid-infrared fiber material: Detuning oscillations in femtosecond mid-infrared spectroscopy
- Author
-
M. Ordu, J. Guo, G. Ng Pack, P. Shah, S. Ramachandran, M. K. Hong, L. D. Ziegler, S. N. Basu, and S. Erramilli
- Subjects
Physics ,QC1-999 - Abstract
Germanium optical fibers hold great promise in extending semiconductor photonics into the fundamentally important mid-infrared region of the electromagnetic spectrum. The demonstration of nonlinear response in fabricated Ge fiber samples is a key step in the development of mid-infrared fiber materials. Here we report the observation of detuning oscillations in a germanium fiber in the mid-infrared region using femtosecond dispersed pump-probe spectroscopy. Detuning oscillations are observed in the frequency-resolved response when mid-infrared pump and probe pulses are overlapped in a fiber segment. The oscillations arise from the nonlinear frequency resolved nonlinear (χ(3)) response in the germanium semiconductor. Our work represents the first observation of coherent oscillations in the emerging field of germanium mid-infrared fiber optics.
- Published
- 2017
- Full Text
- View/download PDF
72. Copper chelation inhibits TGF-β pathways and suppresses epithelial-mesenchymal transition in cancer
- Author
-
E. M. Poursani, D. Mercatelli, P. Raninga, J. L. Bell, F. Saletta, F. V. Kohane, Y. Zheng, J. Rouaen, T. R. Jue, F. T. Michniewicz, E. Kasiou, M. Tsoli, G. Cirillo, S. Waters, T. Shai-Hee, E. Valli, M. Brettle, R. Whan, L. Vahadat, D. Ziegler, J. G. Lock, F. M. Giorgi, K. K. Khanna, and O. Vittorio
- Abstract
Copper is a trace element essential to cellular function with elevated levels implicated in cancer progression. Clinical trials using copper chelators are associated with improved patient survival, however, the molecular mechanisms by which copper depletion inhibits tumor progression are poorly understood. This remains a major hurdle to the clinical translation of copper chelators. Epithelial-mesenchymal transition (EMT) is often exploited by malignant cells to promote growth and metastasis. Transforming growth factor (TGF)-β is a master regulator of EMT and facilitates cancer progression through changes in the tumor and its microenvironment. Herein, we report that a reduction of copper with the chelating agent tetraethylenepentamine (TEPA) inhibited EMT in vitro in three diverse cancer cell types; human triple-negative breast cancer (TNBC), neuroblastoma (NB), and diffuse intrinsic pontine glioma (DIPG) cell lines. Single-molecule imaging demonstrated EMT markers including Vimentin, β-catenin, ZEB1, and p-SMAD2 had increased expression with copper treatment and this pro-mesenchymal shift was rescued by the addition of TEPA. Moreover, SNAI1, ZEB1, and p-SMAD2 demonstrated increased accumulation in the cytoplasm after treating with TEPA. Transcriptomic analyses revealed a significant downregulation of the EMT pathway, including canonical (TGF-β/SMAD2&3) and non-canonical (TGF-β/PI3K/AKT and TGF-β/RAS/RAF/MEK/ERK) TGF signaling pathways. Matrix metalloproteinases MMP-9 and MMP-14 proteins which activate latent TGF-β complexes were also downregulated by TEPA treatment. These molecular changes are consistent with reduced plasma levels of TGF-β we observed in cancer models treated with TEPA. Importantly, copper chelation reduced metastasis to the lung in a TNBC orthotopic syngeneic mouse model. Our studies suggest copper chelation therapy can be used to inhibit EMT-induced metastasis by targeting TGF-β signalling. Because on-target anti-TGF-β therapies are failing in the clinic, copper chelation presents itself as a potential therapy for targeting TGF-β in cancer.
- Published
- 2022
- Full Text
- View/download PDF
73. Exciton fine structure splitting and linearly polarized emission in strained transition-metal dichalcogenide monolayers
- Author
-
M. M. Glazov, Florian Dirnberger, Vinod M. Menon, Takashi Taniguchi, Kenji Watanabe, Dominique Bougeard, Jonas D. Ziegler, and Alexey Chernikov
- Subjects
Condensed Matter - Materials Science ,Condensed Matter::Materials Science ,Condensed Matter - Mesoscale and Nanoscale Physics ,Mesoscale and Nanoscale Physics (cond-mat.mes-hall) ,Materials Science (cond-mat.mtrl-sci) ,FOS: Physical sciences - Abstract
We study theoretically effects of an anisotropic elastic strain on the exciton energy spectrum fine structure and optical selection rules in atom-thin crystals based on transition-metal dichalcogenides. The presence of strain breaks the chiral selection rules at the $\bm K$-points of the Brillouin zone and makes optical transitions linearly polarized. The orientation of the induced linear polarization is related to the main axes of the strain tensor. Elastic strain provides an additive contribution to the exciton fine structure splitting in agreement with experimental evidence obtained from uniaxially strained WSe$_2$ monolayer. The applied strain also induces momentum-dependent Zeeman splitting. Depending on the strain orientation and magnitude, Dirac points with a linear dispersion can be formed in the exciton energy spectrum. We provide a symmetry analysis of the strain effects and develop a microscopic theory for all relevant strain-induced contributions to the exciton fine structure Hamiltonian., Comment: 12 pages, 5 figures
- Published
- 2022
- Full Text
- View/download PDF
74. NIR surface enhanced Raman spectra of biological hemes: Solvation and plasmonic metal effects
- Author
-
Lawrence D. Ziegler, W. Ranjith Premasiri, and Harrison M. Ingraham
- Subjects
biology ,Chemistry ,Cytochrome c ,Solvation ,Photochemistry ,Metal ,symbols.namesake ,chemistry.chemical_compound ,Myoglobin ,visual_art ,visual_art.visual_art_medium ,symbols ,biology.protein ,General Materials Science ,Raman spectroscopy ,Spectroscopy ,Plasmon - Published
- 2021
- Full Text
- View/download PDF
75. Conjugate Acid–Base Interaction Driven Phase Transition at a 2D Air–Water Interface
- Author
-
Lawrence D. Ziegler, Shyamsunder Erramilli, Ramprasath Rajagopal, Onuttom Narayan, and M. K. Hong
- Subjects
Anions ,Phase transition ,Materials science ,ved/biology.organism_classification_rank.species ,010402 general chemistry ,01 natural sciences ,Phase Transition ,Ion ,Phase (matter) ,0103 physical sciences ,Materials Chemistry ,Physical and Theoretical Chemistry ,chemistry.chemical_classification ,010304 chemical physics ,ved/biology ,Air ,Water ,0104 chemical sciences ,Surfaces, Coatings and Films ,Lattice (module) ,chemistry ,Chemical physics ,Adsorption ,Lattice model (physics) ,Conjugate acid ,Organic acid ,Conjugate - Abstract
A lattice model is described to explain a recent striking Sum Frequency Generation (SFG) observation of a cooperative surface adsorption effect for an organic acid system at an air-water interface. The reported anomalous pH-dependent enhancement in p-methylbenzoic acid (pmBA) arises from an interaction between the acid (HA) and its conjugate base anion (A-), which competes with strong Coulombic repulsion between the conjugate bases (A--A -). Using a statistical mechanical approach, this lattice gas model reveals an analogy to well-studied magnetic systems in which the attraction between the two different molecular species leads to a phase transition to a two-dimensional checkerboard phase consisting of a network of anion-acid complexes formed at the low-dielectric air-water interface. Cooperative acid-anion interactions that control partitioning at solution and aerosol interfaces are of interest to fields ranging from oceanic and atmospheric chemistry, pharmacology, and chemical engineering.
- Published
- 2021
- Full Text
- View/download PDF
76. Late Pleistocene–Holocene flood history, flood-sediment provenance and human imprints from the upper Indus River catchment, Ladakh Himalaya
- Author
-
Anil Kumar, Robert J. Wasson, Rajesh Agnihotri, Poonam Chahal, Y. P. Sundriyal, Pradeep Srivastava, Alan D. Ziegler, Choudhurimayum Pankaj Sharma, Saurabh Singhal, and Uma Kant Shukla
- Subjects
geography ,Provenance ,geography.geographical_feature_category ,Pleistocene ,Flood myth ,Indus ,Drainage basin ,Geology ,Physical geography ,Rain shadow ,Monsoon ,Holocene - Abstract
The Indus River, originating from Manasarovar Lake in Tibet, runs along the Indus Tsangpo suture zone in Ladakh which separates the Tethyan Himalaya in the south from the Karakoram zone to the north. Due to the barriers created by the Pir-Panjal ranges and the High Himalaya, Ladakh is located in a rain shadow zone of the Indian summer monsoon (ISM) making it a high-altitude desert. Occasional catastrophic hydrological events are known to endanger lives and properties of people residing there. Evidence of such events in the recent geologic past that are larger in magnitude than modern occurrences is preserved along the channels. Detailed investigation of these archives is imperative to expand our knowledge of extreme floods that rarely occur on the human timescale. Understanding the frequency, distribution, and forcing mechanisms of past extreme floods of this region is crucial to examine whether the causal agents are regional, global, or both on long timescales. We studied the Holocene extreme flood history of the Upper Indus catchment in Ladakh using slackwater deposits (SWDs) preserved along the Indus and Zanskar Rivers. SWDs here are composed of stacks of sand-silt couplets deposited rapidly during large flooding events in areas where a sharp reduction of flow velocity is caused by local geomorphic conditions. Each couplet represents a flood, the age of which is constrained using optically stimulated luminescence for sand and accelerator mass spectrometry and liquid scintillation counter 14C for charcoal specks from hearths. The study suggests occurrence of large floods during phases of strengthened ISM when the monsoon penetrated into arid Ladakh. Comparison with flood records of rivers draining other regions of the Himalaya and those influenced by the East Asian summer monsoon (EASM) indicates asynchronicity with the Western Himalaya that confirms the existing anti-phase relationship of the ISM-EASM that occurred in the Holocene. Detrital zircon provenance analysis indicates that sediment transportation along the Zanskar River is more efficient than the main Indus channel during extreme floods. Post–Last Glacial Maximum human migration, during warm and wet climatic conditions, into the arid upper Indus catchment is revealed from hearths found within the SWDs.
- Published
- 2021
- Full Text
- View/download PDF
77. Fuzzy clustering and distributed model for streamflow estimation in ungauged watersheds
- Author
-
Bahram Choubin, Amirhosein Mosavi, Adrienn Dineva, Fan Zhang, Shahram Khalighi Sigaroodi, Alan D. Ziegler, and Mohammad Golshan
- Subjects
Hydrology ,Hydrometry ,Multidisciplinary ,Watershed ,Fuzzy clustering ,010504 meteorology & atmospheric sciences ,Soil and Water Assessment Tool ,Distributed element model ,Science ,0208 environmental biotechnology ,02 engineering and technology ,01 natural sciences ,Fuzzy logic ,Article ,020801 environmental engineering ,Environmental sciences ,Streamflow ,Environmental science ,Medicine ,Cluster analysis ,0105 earth and related environmental sciences - Abstract
This paper proposes a regionalization method for streamflow prediction in ungauged watersheds in the 7461 km2 area above the Gharehsoo Hydrometry Station in the Ardabil Province, in the north of Iran. First, the Fuzzy c-means clustering method (FCM) was used to divide 46 gauged (19) and ungauged (27) watersheds into homogenous groups based on a variety of topographical and climatic factors. After identifying the homogenous watersheds, the Soil and Water Assessment Tool (SWAT) was calibrated and validated using data from the gauged watersheds in each group. The calibrated parameters were then tested in another gauged watershed that we considered as a pseudo ungauged watershed in each group. Values of R-Squared and Nash–Sutcliffe efficiency (NSE) were both ≥ 0.70 during the calibration and validation phases; and ≥ 0.80 and ≥ 0.74, respectively, during the testing in the pseudo ungauged watersheds. Based on these metrics, the validated regional models demonstrated a satisfactory result for predicting streamflow in the ungauged watersheds within each group. These models are important for managing stream quantity and quality in the intensive agriculture study area.
- Published
- 2021
78. Dynamic risk assessment to improve quality of care in patients with atrial fibrillation
- Author
-
Ursula Ravens, Bushra S. Ilyas, Ulrich Schotten, Isabelle C. Van Gelder, Christian G Meyer, Burcu Vardar, Elena Andreassi Marinelli, Moritz F. Sinner, Stephan Willems, Christophe Leclercq, Renate B. Schnabel, Doreen Haase, Larissa Fabritz, Dierk Thomas, Dobromir Dobrev, Mattias Wieloch, Jeff S. Healey, Emma Svennberg, Paul D. Ziegler, Christina Easter, Stefan H. Hohnloser, Gregory Y.H. Lip, Gerhard Hindricks, A. John Camm, Andreas Goette, Monika Stoll, Irina Savelieva, Tatjana S. Potpara, Guenter Breithardt, Stéphane N. Hatem, Karl Georg Häusler, Rüdiger Smolnik, Alice J Sitch, Reza Wakili, Jan Steffel, Helmut Pürerfellner, Winnie Chua, José L. Merino, Anthony W.S. Chan, Harry J.G.M. Crijns, Thomas Huebner, Paulus Kirchhof, Christina Dimopoulou, Thorsten Lewalter, Stef Zeemering, Kenneth M. Stein, Mirko De Melis, Eduard Guasch, Jordi Heijman, Dipak Kotecha, Lluís Mont, Jonas Oldgren, Michael Nabauer, Michiel Rienstra, Ingo Kutschka, Aaron Isaacs, Lars Eckardt, Hein Heidbuchel, Cardiovascular Centre (CVC), University of Birmingham [Birmingham], University Hospitals Birmingham [Birmingham, Royaume-Uni], Maastricht University Medical Centre (MUMC), Maastricht University [Maastricht], University of Barcelona, University Hospital of Würzburg, University Hospital Hamburg-Eppendorf, Universitaetsklinikum Hamburg-Eppendorf = University Medical Center Hamburg-Eppendorf [Hamburg] (UKE), University of Belgrade [Belgrade], University Medical Center Groningen [Groningen] (UMCG), Asklepios Klinik St. Georg, University Hospital Münster - Universitaetsklinikum Muenster [Germany] (UKM), University of London [London], Pfizer, Medtronic Inc [Minneapolis, MI, USA], European Society of Cardiology (ESC), University Hospital [Essen, Germany], CHU Pitié-Salpêtrière [AP-HP], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU), Sorbonne Université (SU), Université Pierre et Marie Curie - Paris 6 (UPMC), Population Health Research Institute [Hamilton, ON, Canada], Goethe-Universität Frankfurt am Main, University Hospital Göttingen, CHU Pontchaillou [Rennes], Laboratoire Traitement du Signal et de l'Image (LTSI), Université de Rennes (UR)-Institut National de la Santé et de la Recherche Médicale (INSERM), University of Liverpool, La Paz University Hospital, Universitat de Barcelona (UB), University-Hospital Munich-Großhadern [München], Uppsala University, Ordensklinikum Linz Elisabethinen, St George's, University of London, Universität Zürich [Zürich] = University of Zurich (UZH), Boston Scientific, Karolinska Institutet [Stockholm], Heidelberg University Hospital [Heidelberg], University of Groningen [Groningen], University Hospital Essen, SANOFI Recherche, University of Antwerp (UA), Leipzig University, EHRA, 633196, EU Horizon 2020, AFNet, AFNET, MUMC+: MA Cardiologie (9), Cardiologie, RS: Carim - H01 Clinical atrial fibrillation, Fysiologie, RS: FHML MaCSBio, RS: Carim - B01 Blood proteins & engineering, Biochemie, RS: Carim - H08 Experimental atrial fibrillation, Sorbonne Université (SU)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP), Institut National de la Santé et de la Recherche Médicale (INSERM)-Université de Rennes 1 (UR1), and Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)
- Subjects
Technology ,Quality management ,Rate control ,[SDV]Life Sciences [q-bio] ,medicine.medical_treatment ,Medizin ,030204 cardiovascular system & hematology ,0302 clinical medicine ,Risk Factors ,030212 general & internal medicine ,Stroke ,Research priorities ,CATHETER ABLATION ,ROADMAP ,Integrated care ,Atrial fibrillation ,3. Good health ,OPPORTUNITIES ,Treatment Outcome ,Consensus statement ,Screening ,[SDV.IB]Life Sciences [q-bio]/Bioengineering ,Rhythm control ,Cognitive function ,Cardiology and Cardiovascular Medicine ,Risk assessment ,medicine.medical_specialty ,Consensus ,Catheter ablation ,Heart failure ,Outcomes ,DIAGNOSIS ,Risk Assessment ,CLASSIFICATION ,03 medical and health sciences ,Big data ,Anticoagulation ,FUTURE ,Physiology (medical) ,medicine ,MANAGEMENT ,Humans ,Intensive care medicine ,Atrial cardiomyopathy ,business.industry ,Research ,Bleeding ,Quality of care ,Anticoagulants ,EHRA ,medicine.disease ,Lifestyle ,AFNET ,Comorbidity ,PREVENTION ,REDUCTION ,Human medicine ,business - Abstract
Aims The risk of developing atrial fibrillation (AF) and its complications continues to increase, despite good progress in preventing AF-related strokes. Methods and results This article summarizes the outcomes of the 7th Consensus Conference of the Atrial Fibrillation NETwork (AFNET) and the European Heart Rhythm Association (EHRA) held in Lisbon in March 2019. Sixty-five international AF specialists met to present new data and find consensus on pressing issues in AF prevention, management and future research to improve care for patients with AF and prevent AF-related complications. This article is the main outcome of an interactive, iterative discussion between breakout specialist groups and the meeting plenary. AF patients have dynamic risk profiles requiring repeated assessment and risk-based therapy stratification to optimize quality of care. Interrogation of deeply phenotyped datasets with outcomes will lead to a better understanding of the cardiac and systemic effects of AF, interacting with comorbidities and predisposing factors, enabling stratified therapy. New proposals include an algorithm for the acute management of patients with AF and heart failure, a call for a refined, data-driven assessment of stroke risk, suggestions for anticoagulation use in special populations, and a call for rhythm control therapy selection based on risk of AF recurrence. Conclusion The remaining morbidity and mortality in patients with AF needs better characterization. Likely drivers of the remaining AF-related problems are AF burden, potentially treatable by rhythm control therapy, and concomitant conditions, potentially treatable by treating these conditions. Identifying the drivers of AF-related complications holds promise for stratified therapy.
- Published
- 2021
- Full Text
- View/download PDF
79. Cost–effectiveness of an insertable cardiac monitor to detect atrial fibrillation in patients with cryptogenic stroke
- Author
-
Suneet Mittal, Rachelle E Kaplon, Matthew R. Reynolds, Frank W Grimsey Jones, Klaus K. Witte, Sarah C Rosemas, Paul D. Ziegler, L. Sawyer, and Shadi Yaghi
- Subjects
medicine.medical_specialty ,Cost effectiveness ,Cost-Benefit Analysis ,Population ,030204 cardiovascular system & hematology ,03 medical and health sciences ,0302 clinical medicine ,Recurrent stroke ,Internal medicine ,Atrial Fibrillation ,Humans ,Medicine ,In patient ,cardiovascular diseases ,education ,Stroke ,reproductive and urinary physiology ,Ischemic Stroke ,education.field_of_study ,business.industry ,Health Policy ,Atrial fibrillation ,Bleed ,equipment and supplies ,medicine.disease ,Cryptogenic stroke ,embryonic structures ,Electrocardiography, Ambulatory ,Cardiology ,business ,030217 neurology & neurosurgery ,circulatory and respiratory physiology - Abstract
Background: We assessed cost–effectiveness of insertable cardiac monitors (ICMs) in a US cryptogenic stroke population. Materials & methods: We modelled lifetime costs and quality-adjusted life years for three monitoring strategies post cryptogenic stroke: ICM starting immediately, ICM starting after Holter monitoring (delayed ICM) and standard of care involving intermittent ECG and Holter monitoring. Patient characteristics and detection efficacy were based on the CRYSTAL-AF trial. AF detection altered the modelled anticoagulation therapy and subsequent stroke and bleed risks. Results & conclusion: Immediate ICM was found to be cost-effective versus standard of care and cost-saving versus delayed ICM. Results were robust to sensitivity analyses. ICMs are a cost-effective diagnostic tool for the prevention of recurrent stroke in a US cryptogenic stroke population.
- Published
- 2021
- Full Text
- View/download PDF
80. Estimation of Root Zone Soil Moisture Using Apparent Thermal Inertia With MODIS Imagery Over a Tropical Catchment in Northern Thailand.
- Author
-
Tzu-Yin Chang, Yi-Chen Wang, Chen-Chieh Feng, Alan D. Ziegler, Thomas W. Giambelluca, and Yuei-An Liou
- Published
- 2012
- Full Text
- View/download PDF
81. Pathogenic waterborne free-living amoebae: An update from selected Southeast Asian countries.
- Author
-
Mohamad Azlan Abdul Majid, Tooba Mahboob, Brandon G J Mong, Narong Jaturas, Reena Leeba Richard, Tan Tian-Chye, Anusorn Phimphila, Panomphanh Mahaphonh, Kyaw Nyein Aye, Wai Lynn Aung, Joon Chuah, Alan D Ziegler, Atipat Yasiri, Nongyao Sawangjaroen, Yvonne A L Lim, and Veeranoot Nissapatorn
- Subjects
Medicine ,Science - Abstract
Data on the distribution of free-living amoebae is still lacking especially in Southeast Asian region. The aquatic environment revealed a high occurrence of free-living amoebae (FLA) due to its suitable condition and availability of food source, which subsequently causes infection to humans. A total of 94 water samples consisted of both treated and untreated from Laos (31), Myanmar (42), and Singapore (21) were investigated for the presence of pathogenic FLA. Each water sample was filtered and cultured onto non-nutrient agar seeded with live suspension of Escherichia coli and incubated at room temperature. Morphological identification was conducted for both trophozoites and cysts via microscopic stains (Giemsa and immunofluorescence). The presence of Naegleria-like structures was the most frequently encountered in both treated and untreated water samples, followed by Acanthamoeba-like and Vermamoeba-like features. To identify the pathogenic isolates, species-specific primer sets were applied for molecular identification of Acanthamoeba, Naegleria, and Vermamoeba. The pathogenic species of Acanthamoeba lenticulata and A. triangularis were detected from untreated water samples, while Vermamoeba vermiformis was found in both treated and untreated water samples. Our results suggested that poor water quality as well as inadequate maintenance and treatment might be the cause of this alarming problem since chlorine disinfection is ineffective in eradicating these amoebas in treated water samples. Regular monitoring and examination of water qualities are necessary in order to control the growth, hence, further preventing the widespread of FLA infections among the public.
- Published
- 2017
- Full Text
- View/download PDF
82. Correction: Pathogenic waterborne free-living amoebae: An update from selected Southeast Asian countries.
- Author
-
Mohamad Azlan Abdul Majid, Tooba Mahboob, Brandon G J Mong, Narong Jaturas, Reena Leeba Richard, Tan Tian-Chye, Anusorn Phimphila, Panomphanh Mahaphonh, Kyaw Nyein Aye, Wai Lynn Aung, Joon Chuah, Alan D Ziegler, Atipat Yasiri, Nongyao Sawangjaroen, Yvonne A L Lim, and Veeranoot Nissapatorn
- Subjects
Medicine ,Science - Abstract
[This corrects the article DOI: 10.1371/journal.pone.0169448.].
- Published
- 2017
- Full Text
- View/download PDF
83. High-intensity monsoon rainfall variability and its attributes: a case study for Upper Ganges Catchment in the Indian Himalaya during 1901–2013
- Author
-
Alan D. Ziegler, Winston T. L. Chow, Robert J. Wasson, and Alok Bhardwaj
- Subjects
021110 strategic, defence & security studies ,Atmospheric Science ,geography ,geography.geographical_feature_category ,010504 meteorology & atmospheric sciences ,0211 other engineering and technologies ,Drainage basin ,Magnitude (mathematics) ,Climate change ,02 engineering and technology ,Monsoon ,01 natural sciences ,Latitude ,Trend analysis ,Arctic oscillation ,Natural hazard ,Earth and Planetary Sciences (miscellaneous) ,Environmental science ,Physical geography ,0105 earth and related environmental sciences ,Water Science and Technology - Abstract
High-intensity monsoon rainfall in the Indian Himalaya generates multiple environmental hazards. This study examines the variability in long-term trends (1901–2013) in the intensity and frequency of high-intensity monsoon rainfall events of varying depths (high, very high and extreme) in the Upper Ganges Catchment in the Indian Himalaya. Using trend analysis on the Indian Meteorological Department (IMD) rainfall dataset, we find statistically significant positive trends in all categories of monsoon rainfall intensity and frequency over the 113-year period. The majority of the trends for both intensity and frequency are spatially located in the Higher Himalayan region encompassing upstream sections of the Mandakini, Alaknanda and Bhagirathi River systems. The extreme rainfall trends for both intensity and frequency are found to be only located in the vicinity of the upstream section of the Mandakini Catchment. Further, we explored the relationship between the Arctic Oscillation (AO) climate system and the frequency of occurrence of high-intensity rainfall events. Results indicate that AO is more likely to influence the occurrence of extreme monsoon events when it has a higher magnitude of negative AO phase. This study will help in better understanding of the influence of climate change at higher latitudes on mid-latitude rainfall extremes, particularly in the Himalayas. The implications of the findings are that statistically significant increasing rainfall depths and frequency in the Higher Himalayan region support the notion of higher frequency of rainfall-induced hazards in the future.
- Published
- 2021
- Full Text
- View/download PDF
84. Promoting sustainability education through hands-on approaches: a tree carbon sequestration exercise in a Singapore green space
- Author
-
Sorain J. Ramchunder and Alan D. Ziegler
- Subjects
Health (social science) ,Knowledge management ,010504 meteorology & atmospheric sciences ,Sociology and Political Science ,media_common.quotation_subject ,Geography, Planning and Development ,Student engagement ,Case Report ,010501 environmental sciences ,Management, Monitoring, Policy and Law ,01 natural sciences ,Environmental science ,Living lab ,Transferable skills analysis ,Tree carbon biomass assessment ,0105 earth and related environmental sciences ,Nature and Landscape Conservation ,media_common ,Sustainable development ,Global and Planetary Change ,Teamwork ,Allometry ,Singapore carbon footprint ,Ecology ,business.industry ,Collaborative learning ,Sustainability education ,Climate change mitigation ,Sustainability ,business - Abstract
During a university class project related to climate change mitigation strategies, we utilized a university green space as a “living laboratory” for collaborative learning exercise to estimate landscape-level carbon biomass storage. The key objective of the exercise was to foster sustainability awareness with regard to the effectiveness of tree-planting initiatives to offset carbon emissions. Collaborative learning is a process by which students work together in small groups to accomplish a common goal. As experiences are active, social and student-owned, the process leads to the development of a variety of cognitive and transferable skills that are beneficial in academia and the workplace. Through data collection/analysis, the carbon biomass exercise not only allowed students to assess critically the efficacy of a tree-planting initiative as a means to sequester carbon, but they became aware of the difficulties in performing research on complex environmental issues. The intention of the research was to give students an opportunity to practice data collection, data analysis, problem solving, teamwork, communication and scientific literacy skills, meanwhile utilizing the campus open green space to enhance the knowledge discovery process. Informal assessment and discussions with students demonstrated that the activity was successful in reaching a wide range of students with varying backgrounds and initial attitudes about climate change mitigating strategies, which was our objective. Our case study demonstrates how learning objectives can be integrated with university sustainability initiatives to improve learning and student engagement. Finally, we see green spaces as dynamic settings for learning about physical processes and issues related to environmental management and sustainability.
- Published
- 2021
85. Water quality impacts of young green roofs in a tropical city: a case study from Singapore
- Author
-
Elvagris Segovia, ALAN D ZIEGLER, and Han She Lim
- Subjects
green roof water quality ,eutrophication ,Urbanization. City and country ,nutrients ,carbon ,trace metals ,Environmental engineering ,TA170-171 ,HT361-384 ,General Economics, Econometrics and Finance - Abstract
This study examined the effects of two substrates (SOIL and COMMERCIAL) and grass on the green roof runoff quality in Singapore. Ten events were sampled over a 9-month period. Rainfall and green roof runoff from grass and bare experimental configurations were tested for total organic carbon (TOC), nitrogen and phosphorus nutrients (NO3−-N and PO43−-P), cations/anions and trace metals (Fe, Cu, Zn, Cd and Pb). All configuration units neutralised acid rainfall and removed metals except Fe despite their proximity to an industrial area. Concentrations decrease over the monitoring period for most water quality variables. The COMMERCIAL (COM) configurations elevated Cl− (3.8–10.8 ppm), SO42− (1.5–32.4 ppm), NO3−-N (7.8–75.6 ppm) and NH4+-N (22.0–53.1 ppm) concentrations in the runoff. Concentrations of NO3−-N (4.5–67.7 ppm) and NH4+-N (14.7–53.0 ppm) remained high at the end of the monitoring period for the COMgrass configuration, even with dilution from monsoon rainfall, making it suitable as an irrigation water source and a fertiliser substitute. The SOIL substrate retained N-nutrients, TOC and trace metals with concentrations comparable or below rainfall inputs. This substrate is suitable for widespread green roof applications in Singapore and other tropical cities. We recommend substrate testing before their approval for use on green roofs and encourage the long-term monitoring of these systems. HIGHLIGHTS All configurations removed trace metals and neutralised acid rainfall despite close proximity to an industrial area.; Substrates low in organic matter content were found to be suitable for widespread implementation in Singapore.; High nutrient concentrations in green roof runoff make them suitable for irrigating urban greenery.
- Published
- 2021
- Full Text
- View/download PDF
86. Aerosol presence reduces the diurnal temperature range: an interval when the COVID-19 pandemic reduced aerosols revealing the effect on climate
- Author
-
Alan D. Ziegler, Tzung-May Fu, Xu Feng, Zhenzhong Zeng, Xin Yang, Dashan Wang, Jie Wu, Lihong Zhou, and Shijie Hu
- Subjects
010504 meteorology & atmospheric sciences ,Anomaly (natural sciences) ,Global warming ,Diurnal temperature variation ,Climate change ,010501 environmental sciences ,01 natural sciences ,Pollution ,Analytical Chemistry ,Aerosol ,Weather station ,Atmosphere ,Chemistry (miscellaneous) ,Climatology ,Atmospheric chemistry ,Environmental Chemistry ,Environmental science ,0105 earth and related environmental sciences - Abstract
The immense reduction in aerosol levels during the COVID-19 pandemic provides an opportunity to reveal how atmospheric chemistry is regulating our climate, among which the effect of aerosols on climate is a phenomenon of great interest but still in hot debate. The Intergovernmental Panel on Climate Change (IPCC) has continually identified the effect of aerosols on climate to have the largest uncertainty among the factors contributing to global climate change. Several studies indicate an inverse relationship between aerosol presence in the atmosphere and the diurnal surface air temperature range (DTR). Herein, we test this relationship by analyzing the DTR values from in situ weather station records for periods before and during the COVID-19 epidemic in China where aerosol levels have substantially reduced, compared with the climatological mean levels for a 19 year period. Our analyses find that DTRs from February to June during the COVID-19 pandemic are greater than 3 standard deviations above the climatological mean DTR. This anomaly has never occurred before in the 21st century and is at least in part associated with the observed reduction in aerosols.
- Published
- 2021
- Full Text
- View/download PDF
87. Chemical enhancement effects on protoporphyrin IX surface‐enhanced Raman spectra: Metal substrate dependence and a vibronic theory analysis
- Author
-
James McNeely, Lawrence D. Ziegler, W. Ranjith Premasiri, and Harrison M. Ingraham
- Subjects
Theory analysis ,chemistry.chemical_compound ,symbols.namesake ,Materials science ,Protoporphyrin IX ,chemistry ,symbols ,Metal substrate ,General Materials Science ,Raman spectroscopy ,Photochemistry ,Spectroscopy - Published
- 2020
- Full Text
- View/download PDF
88. Estimating carbon biomass in forests using incomplete data
- Author
-
Theodore A. Evans, Alan D. Ziegler, Tak Fung, Anuj Jain, and Lahiru S. Wijedasa
- Subjects
chemistry ,Environmental science ,Biomass ,Climate change ,chemistry.chemical_element ,Forestry ,Carbon ,Ecology, Evolution, Behavior and Systematics ,Biomass carbon ,Tropical deforestation ,Basal area - Published
- 2020
- Full Text
- View/download PDF
89. Dairy calf growth performance when fed a modified accelerated milk replacer program
- Author
-
D. Schimek, Brittney M. Jaeger, D. Ziegler, David P. Casper, B. Ziegler, and Hugh Chester-Jones
- Subjects
Starter ,Animal science ,Dairy heifer ,Chemistry ,Dairy calf ,Weaning ,Animal Science and Zoology ,Food Science - Abstract
Objective Our previous studies demonstrated that a modified accelerated milk replacer (MR) having a 24:20 CP:fat concentration fed at higher feeding rates (FR) resulted in improved growth performance and G:F, but the result was not linear. The objective of the current study was to evaluate preweaning (d 1 to 42) and postweaning (d 43 to 56) calf performance when a modified accelerated MR was fed at greater FR compared with a MR having similar or greater CP and lower fat concentrations. Materials and Methods A total of 126 (2 to 5 d old) Holstein heifer calves (40.1 ± 0.76 kg) were blocked by birthdate and randomly assigned to 1 of 5 treatments. Treatments of MR fed at 14.7% solids were (1) control (C−): all milk 24:20 MR fed at 0.26 kg at 2×/d from d 1 to 35; (2) C+: C− MR fed at 0.32 kg 2×/d from d 1 to 35; (3) LF: CP and low fat (24:16) MR fed at 0.32 kg 2×/d from d 1 to 35; (4) LF+: LF MR fed at 0.32 kg 2×/d from d 1 to 7 and at 0.39 kg from d 8 to 35; and (5) HP+: high CP:LF MR (26:16) using the same FR as LF+. All MR were fed 1×/d from d 36 to weaning at d 42 with water and 18% CP texturized calf starter offered free choice at all times. Results and Discussion Calves fed C+ had greater (P Implications and Applications This study demonstrates that feeding a modified accelerated MR (24:20) at a moderate FR improves ADG and frame measurements for calves fed MR having similar or different CP and fat concentrations. The development of a modified accelerated feeding program optimized the protein-to-energy ratio for producing a dairy heifer with a frame that is taller and wider, without having a postweaning BW gain slump.
- Published
- 2020
- Full Text
- View/download PDF
90. Growth performance of newborn dairy calves fed a milk replacer containing 24% crude protein and 20% fat fed at different feeding rates
- Author
-
D. Schimek, David P. Casper, D. Ziegler, Brittney M. Jaeger, B. Ziegler, and Hugh Chester-Jones
- Subjects
Animal science ,Starter ,Weaning ,Animal Science and Zoology ,Biology ,Protein concentration ,Feed conversion ratio ,Food Science - Abstract
Objective The objective was to evaluate the preweaning (d 1 to 42) and postweaning (d 43 to 56) performance and health of calves fed a 24% CP:20% fat milk replacer (MR) at different feeding rates based on our previous work that calves fed greater feeding rates of MR demonstrated improved growth. Materials and Methods A total of 108 (2- to 5-d-old) Holstein heifer calves (40 ± 0.69 kg) were randomly assigned to 1 of 4 treatments. The same all-milk-protein MR was fed at 14.7% solids, with treatments of (1) control (MR57): MR fed at 0.57 kg daily from d 1 to 35; (2) MR71: MR fed at 0.71 kg daily from d 1 to 35; (3) MR85: MR fed at 0.68 kg daily from d 1 to 7 and at 0.85 kg daily from d 8 to 35; and (4) MR99: MR fed at 0.68 kg daily from d 1 to 7 and at 0.99 kg daily from d 8 to 35. All treatments were fed MR one time per day from d 36 to weaning, after d 42 with water, and an 18% CP texturized calf starter offered free choice. Results and Discussion Preweaning and overall ADG (0.78, 0.82, 0.83, and 0.85 kg/d for MR57, MR71, MR85, and MR99, respectively) were greater (P 0.10) and intermediate. Overall d 1 to 56 calf starter intakes were greater (P 0.10). Preweaning G:F was lowest for calves fed MR57, whereas d 1 to 56 G:F (0.49, 0.52, 0.52, and 0.54 kg/kg of DM) was greater (P Implications and Applications This study demonstrated that higher feeding rate of a 24:20 MR resulted in increased ADG and feed conversion (G:F).
- Published
- 2020
- Full Text
- View/download PDF
91. Anomalous pH-Dependent Enhancement of p-Methyl Benzoic Acid Sum-Frequency Intensities: Cooperative Surface Adsorption Effects
- Author
-
Mi K. Hong, Lawrence D. Ziegler, Christina M. Miller, Xin Chen, Shane W. Devlin, Richard S. Andino, Ramprasath Rajagopal, Shyamsunder Erramilli, and Jian Liu
- Subjects
010304 chemical physics ,Chemistry ,Ph dependent ,010402 general chemistry ,01 natural sciences ,0104 chemical sciences ,chemistry.chemical_compound ,Adsorption ,0103 physical sciences ,Physical chemistry ,Carboxylate ,Physical and Theoretical Chemistry ,Spectroscopy ,Benzoic acid - Abstract
Vibrational sum-frequency generation (SFG) spectroscopy is used to determine the surface pKa of p-methyl benzoic acid (pMBA) at the air-water interface, by monitoring the carbonyl and carboxylate s...
- Published
- 2020
- Full Text
- View/download PDF
92. Growth performance of newborn dairy calves fed a milk replacer with 2 protein concentrations at 2 feeding rates
- Author
-
Hugh Chester-Jones, David P. Casper, B. Ziegler, D. Schimek, Mary Raeth, Brittney M. Jaeger, and D. Ziegler
- Subjects
Animal science ,Starter ,Chemistry ,High protein ,Animal Science and Zoology ,Feed conversion ratio ,Protein concentration ,Food Science - Abstract
Objective The objective was to evaluate the growth performance by calves fed a conventional milk replacer (MR) or modified accelerated MR (24% CP) to prevent the slump in postweaning calf starter intake and feed efficiency. Materials and Methods A total of 104 (1 to 5 d old) Holstein heifer calves (39.3 ± 0.66 kg) were assigned randomly to 1 of 4 MR treatments to evaluate preweaning (1 to 42 d) and postweaning (43 to 56 d) performance in a 2 × 2 factorial arrangement of CP concentrations [20% CP or 24% CP high protein (HP) with feeding rates (FR) of 0.57 or 0.68 kg/d]. Treatments were MR fed at 15% solids (as fed): (1) control (CP1): a 20% CP:20% fat MR fed at 0.284 kg 2×/d for 35 d; (2) CP2: the 20:20 MR fed at 0.34 kg 2×/d for 35 d; (3) HP1: a 24:20 MR fed at CP1 rate; and (4) HP2: the 24:20 MR fed at CP2 rate. Results and Discussion No interactions of CP by FR were detected for growth parameters. During 1 to 14 d, calves fed higher MR FR (CP2 and HP2) had greater (P 0.10). Intakes of calf starter from 1 to 56 d were similar (P > 0.10) for calves fed MR with different CP concentrations (0.77 and 0.78 kg/d), whereas calf starter intake (0.81 and 0.74 kg/d) was reduced (P 0.01) for calves fed different CP concentrations (0.54 and 0.55 kg/kg) but were improved when fed higher MR FR (0.53 and 0.56 kg/kg). However, a trend (P Implications and Applications Feeding calves a conventional MR (20%CP:20% fat) at different FR with different CP concentrations resulted in similar performance. Feeding a higher CP MR (24% CP:20% fat) at higher FR did not affect preweaning gain of dairy calves.
- Published
- 2020
- Full Text
- View/download PDF
93. Doubling of annual forest carbon loss over the tropics during the early twenty-first century
- Author
-
Yu Feng, Zhenzhong Zeng, Timothy D. Searchinger, Alan D. Ziegler, Jie Wu, Dashan Wang, Xinyue He, Paul R. Elsen, Philippe Ciais, Rongrong Xu, Zhilin Guo, Liqing Peng, Yiheng Tao, Dominick V. Spracklen, Joseph Holden, Xiaoping Liu, Yi Zheng, Peng Xu, Ji Chen, Xin Jiang, Xiao-Peng Song, Venkataraman Lakshmi, Eric F. Wood, Chunmiao Zheng, Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), ICOS-ATC (ICOS-ATC), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), and This study was supported by the National Natural Science Foundation of China (grants no. 42071022, 41861124003 and 41890852) and the start-up fund provided by Southern University of Science and Technology (no. 29/Y01296122)
- Subjects
tropical forest ,[SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere ,Global and Planetary Change ,Ecology ,LAND-USE ,Renewable Energy, Sustainability and the Environment ,IMPACT ,Geography, Planning and Development ,EXPANSION ,carbon loss ,Management, Monitoring, Policy and Law ,PROTECTED AREAS ,CULTIVATION ,Global Forest Change (GFC) ,Urban Studies ,carbon cycle ,DRIVERS ,MAP ,STOCKS ,DEFORESTATION ,[SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces, environment ,DIOXIDE EMISSIONS ,Nature and Landscape Conservation ,Food Science - Abstract
Previous estimates of tropical forest carbon loss in the twenty-first century using satellite data typically focus on its magnitude, whereas regional loss trajectories and associated drivers are rarely reported. Here we used different high-resolution satellite datasets to show a doubling of gross tropical forest carbon loss worldwide from 0.97 ± 0.16 PgC yr−1 in 2001–2005 to 1.99 ± 0.13 PgC yr−1 in 2015–2019. This increase in carbon loss from forest conversion is higher than in bookkeeping models forced by land-use statistical data, which show no trend or a slight decline in land-use emissions in the early twenty-first century. Most (82%) of the forest carbon loss is at some stages associated with large-scale commodity or small-scale agriculture activities, particularly in Africa and Southeast Asia. We find that ~70% of former forest lands converted to agriculture in 2001–2019 remained so in 2020, confirming a dominant role of agriculture in long-term pan-tropical carbon reductions on formerly forested landscapes. The acceleration and high rate of forest carbon loss in the twenty-first century suggest that existing strategies to reduce forest loss are not successful; and this failure underscores the importance of monitoring deforestation trends following the new pledges made in Glasgow.
- Published
- 2022
- Full Text
- View/download PDF
94. IDF2022-0829 Painful diabetic peripheral neuropathy: patients from four European countries report about its impact on their lives
- Author
-
M. Maderuelo Labrador, S. Brill, M. Eerdekens, G. Petersen, A. de Rooij-Peek, D. Ryan, A. Reta, N. Schaper, S. Tesfaye, A. Truini, T. Tölle, and D. Ziegler
- Subjects
Endocrinology ,Endocrinology, Diabetes and Metabolism ,Internal Medicine ,General Medicine - Published
- 2023
- Full Text
- View/download PDF
95. 57P Deciphering the role of E2F transcription factor-1 in glutamine metabolism
- Author
-
K. Huber, R. Dreos, S. Geller, V. Barquissau, D. Ziegler, D. Tavernari, A. Giralt, H. Gallart-Ayala, G. Ciriello, J. Ivanisevic, M. Pichler, and L. Fajas
- Subjects
Cancer Research ,Oncology - Published
- 2023
- Full Text
- View/download PDF
96. Rewetting global wetlands effectively reduces major greenhouse gas emissions
- Author
-
Junyu Zou, Alan D. Ziegler, Deliang Chen, Gavin McNicol, Philippe Ciais, Xin Jiang, Chunmiao Zheng, Jie Wu, Jin Wu, Ziyu Lin, Xinyue He, Lee E. Brown, Joseph Holden, Zuotai Zhang, Sorain J. Ramchunder, Anping Chen, Zhenzhong Zeng, Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), and Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)
- Subjects
[SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere ,General Earth and Planetary Sciences ,[SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces, environment - Abstract
International audience
- Published
- 2022
- Full Text
- View/download PDF
97. An artificial intelligence reconstruction of global gridded surface winds
- Author
-
Lihong, Zhou, Haofeng, Liu, Xin, Jiang, Alan D, Ziegler, Cesar, Azorin-Molina, Jiang, Liu, Zhenzhong, Zeng, National Natural Science Foundation of China, Southern University of Science and Technology (China), Ministerio de Ciencia, Innovación y Universidades (España), Agencia Estatal de Investigación (España), and Generalitat Valenciana
- Subjects
Multidisciplinary ,Artificial Intelligence ,Wind - Abstract
Gridded wind speed data products with global coverage and continuous long-term time series are widely used in many applications, such as evaluating wind energy potential [1] and drought processes [2]. However, some available products do not accurately reproduce observed wind speed trends on land [3], [4], leading to biased or inaccurate conclusions in studies on wind-related phenomena. In-situ weather stations involve direct measurements that accurately preserve wind speed trends. Still, the uneven distribution and incomplete time series have constrained their widespread applications in regional and global analyses. These limitations, which we have encountered firsthand in investigating the global wind stilling and reversal phenomena [4], have inspired us to create a new global gridded surface wind product that preserves observed wind patterns and trends., This work was supported by the National Natural Science Foundation of China (42071022), the start-up fund provided by Southern University of Science and Technology (29/Y01296122), and Highlight Project on Water Security and Global Change of Southern University of Science and Technology (G02296302). Cesar Azorin-Molina was supported by Evaluación y atribución de la variabilidad de la velocidad media y las rachas máximas de viento: causas del fenómeno stilling (RTI2018-095749-A-100), Cambios observados, proyecciones futuras e índices de la velocidad del viento y sus extremos en la Comunidad Valenciana (AICO/2021/023), and the Spanish National Research Centre Interdisciplinary Thematic Platform PTI-CLIMA. We thank Met Office (HadISD), ECMWF (ERA5), and CMIP6 for providing wind speed data used in this work.
- Published
- 2022
98. Floodplain sediment from a 100-year-recurrence flood in 2005 of the Ping River in northern Thailand
- Author
-
S. H. Wood and A. D. Ziegler
- Subjects
Technology ,Environmental technology. Sanitary engineering ,TD1-1066 ,Geography. Anthropology. Recreation ,Environmental sciences ,GE1-350 - Abstract
The tropical storm, floodwater, and the floodplain-sediment layer of a 100-year recurrence flood are examined to better understand characteristics of large monsoon floods on medium-sized rivers in northern Thailand. Storms producing large floods in northern Thailand occur early or late in the summer rainy season (May–October). These storms are associated with tropical depressions evolving from typhoons in the South China Sea that travel westward across the Indochina Peninsula. In late September, 2005, the tropical depression from Typhoon Damrey swept across northern Thailand delivering 100–200 mm/day at stations in mountainous areas. Peak flow from the 6355-km2 drainage area of the Ping River upstream of the city of Chiang Mai was 867 m3s−1 (river-gage of height 4.93 m) and flow greater than 600 m3s−1 lasted for 2.5 days. Parts of the city of Chiang Mai and some parts of the floodplain in the intermontane Chiang Mai basin were flooded up to 1-km distant from the main channel. Suspended-sediment concentrations in the floodwater were measured and estimated to be 1000–1300 mg l−1. The mass of dry sediment (32.4 kg m-2), measured over a 0.32-km2 area of the floodplain is relatively high compared to reports from European and North American river floods. Average wet sediment thickness over the area was 3.3 cm. Sediment thicker than 8 cm covered 16 per cent of the area, and sediment thicker than 4 cm covered 44 per cent of the area. High suspended-sediment concentration in the floodwater, flow to the floodplain through a gap in the levee afforded by the mouth of a tributary stream as well as flow over levees, and floodwater depths of 1.2 m explain the relatively large amount of sediment in the measured area. Grain-size analyses and examination of the flood layer showed about 15-cm thickness of massive fine-sandy silt on the levee within 15-m of the main channel, sediment thicker than 6 cm within 200 m of the main channel containing a basal coarse silt, and massive clayey silt beyond 200 m. The massive clayey silt would not be discernable as a separate layer in section of similar deposits. The fine-sand content of the levee sediment and the basal coarse silt of sediment within 200 m of the main channel are sedimentological features that may be useful in identifying flood layers in a stratigraphic section of floodplain deposits.
- Published
- 2008
99. Simulation of Daily Snapshot Rhythm Monitoring to Identify Atrial Fibrillation in Continuously Monitored Patients with Stroke Risk Factors.
- Author
-
Yuichiro Yano, Philip Greenland, Donald M Lloyd-Jones, Emile G Daoud, Jodi L Koehler, and Paul D Ziegler
- Subjects
Medicine ,Science - Abstract
BACKGROUND:New technologies are diffusing into medical practice swiftly. Hand-held devices such as smartphones can record short-duration (e.g., 1-minute) ECGs, but their effectiveness in identifying patients with paroxysmal atrial fibrillation (AF) is unknown. METHODS:We used data from the TRENDS study, which included 370 patients (mean age 71 years, 71% men, CHADS2 score≥1 point: mean 2.3 points) who had no documentation of atrial tachycardia (AT)/AF or antiarrhythmic or anticoagulant drug use at baseline. All were subsequently newly diagnosed with AT/AF by a cardiac implantable electronic device (CIED) over one year of follow-up. Using a computer simulation approach (5,000 repetitions), we estimated the detection rate for paroxysmal AT/AF via daily snapshot ECG monitoring over various periods, with the probability of detection equal to the percent AT/AF burden on each day. RESULTS:The estimated AT/AF detection rates with snapshot monitoring periods of 14, 28, 56, 112, and 365 days were 10%, 15%, 21%, 28%, and 50% respectively. The detection rate over 365 days of monitoring was higher in those with CHADS2 scores ≥2 than in those with CHADS2 scores of 1 (53% vs. 38%), and was higher in those with AT/AF burden ≥0.044 hours/day compared to those with AT/AF burden
- Published
- 2016
- Full Text
- View/download PDF
100. Dark exciton-exciton annihilation in monolayer WSe2
- Author
-
Daniel Erkensten, Samuel Brem, Koloman Wagner, Roland Gillen, Raül Perea-Causín, Jonas D. Ziegler, Takashi Taniguchi, Kenji Watanabe, Janina Maultzsch, Alexey Chernikov, and Ermin Malic
- Subjects
Other Physics Topics ,Condensed Matter - Mesoscale and Nanoscale Physics ,Condensed Matter::Other ,Atom and Molecular Physics and Optics ,FOS: Physical sciences ,02 engineering and technology ,Condensed Matter Physics ,Condensed Matter::Mesoscopic Systems and Quantum Hall Effect ,021001 nanoscience & nanotechnology ,01 natural sciences ,Condensed Matter::Materials Science ,Mesoscale and Nanoscale Physics (cond-mat.mes-hall) ,0103 physical sciences ,010306 general physics ,0210 nano-technology - Abstract
The exceptionally strong Coulomb interaction in semiconducting transition-metal dichalcogenides (TMDs) gives rise to a rich exciton landscape consisting of bright and dark exciton states. At elevated densities, excitons can interact through exciton-exciton annihilation (EEA), an Auger-like recombination process limiting the efficiency of optoelectronic applications. Although EEA is a well-known and particularly important process in atomically thin semiconductors determining exciton lifetimes and affecting transport at elevated densities, its microscopic origin has remained elusive. In this joint theory-experiment study combining microscopic and material-specific theory with time- and temperature-resolved photoluminescence measurements, we demonstrate the key role of dark intervalley states that are found to dominate the EEA rate in monolayer WSe$_2$. We reveal an intriguing, characteristic temperature dependence of Auger scattering in this class of materials with an excellent agreement between theory and experiment. Our study provides microscopic insights into the efficiency of technologically relevant Auger scattering channels within the remarkable exciton landscape of atomically thin semiconductors., 17 pages, 6 figures
- Published
- 2021
- Full Text
- View/download PDF
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.