238 research outputs found
Chern insulator with a nearly flat band in the metal-organic- framework-based Kagome lattice
No full textBased on first-principles density-functional theory (DFT) calculations, we report that the transitionmetal bis-dithiolene, M3C12S12 (M= Mn and Fe), complexes can be a two-dimensional (2D) ferromagnetic insulator with nontrivial Chern number. Among various synthetic pathways leading to metal bis-dithiolenes, the simplest choice of ligand, Benzene-hexathiol, connecting metal cations to form a Kagome lattice is studied following the experimental report of time-reversal symmetric isostructural compound Ni3C12S12. We show sulfur and carbon-based ligands play the key role in making the complexes topologically nontrivial. An unusual topological quantum phase transition induced by the on-site Coulomb interaction brings a nearly flat band with a nonzero Chern number as the highest occupied band. With this analysis we explain the electronic structure of the class M3C12S12 and predict the existence of nearly flat band with nonzero Chern number and it can be a fractional Chern insulator candidate with carrier doping. © The Author(s) 201911sciescopu
Secure multi-gigabit optical link design for high energy physics experiment with acceleration of more secure RC4 variant in reconfigurable platform
No full textMany cryptographic attacks are capable to break RC4. Still RC4 becomes alive in crypto community with several variants. Insufficient key schedule is the most important weakness of RC4 where the first bytes of output reveals information about the key. The loop-holes can be corrected by discarding initial portion of the output stream [1] which is known as RC4-dropN (N is a multiple of 256, such as 768 or 1024). Here we shows RC4 can be made more secured if an additional RC4-like Post-KSA Random Shuffling (PKRS) process is introduced between KSA and PRGA. The PKRS process is tuned to form as many S-boxes as required by particular design architectures involving multiple coprocessors, each one undertaking byte-by-byte processing. Following a recent idea [2, 3] the speed of execution of each processor is also enhanced by another fold if the byte-bybyte processing is replaced by a scheme of processing two consecutive bytes together. Adopting some new innovative concepts, three hardware design architectures are proposed in a suitable FPGA embedded system involving 1, 2 and 4 coprocessors functioning in parallel and a study is made on accelerating RC4 by processing bytes in byte-by-byte mode achieving throughputs from l.-byte-in-1 -clock to 4-bytes-in- 1-clock. The hardware designs are appropriately upgraded to accelerate RC4 further by processing 2 consecutive RC4 bytes together and it has been possible to achieve a maximum throughput of 8-bytes per clock in Xilinx Virtex-5 LX110t FPGA [4] architecture followed by secured communication High Energy Physics (HEP) application that preserves the DC-balancing of the link and permits forward error correction (FEC) along with encryption
Spatial averaging effects on the streamwise and wall-normal velocity measurements in a wall-bounded turbulence using a cross-wire probe
No full textThe spatial averaging effects due to a cross-wire probe on the measured turbulence statistics in a wall-bounded flow are investigated using a combined approach of direct numerical simulation data, theoretical methods and experiments. In particular, the wire length (l), spacing ( ) and angle ( ) of a cross-wire probe configured to measure the streamwise and wall-normal velocities are systematically varied to isolate effects of each parameter. The measured streamwise velocity from a cross-wire probe is found to be an average of the filtered velocities sensed by the two wires. Thus, in general, an increase in the sensor dimensions when normalised by viscous units leads to an attenuated variance for the streamwise velocity ( ), resulting from a larger contribution to the spatial averaging process from poorly correlated velocities. In contrast, the variance for the wall-normal velocity ( ) can be amplified, and this is shown to be the result of an additional contributing term (compared to ) due to differences in the filtered wire-normal velocity between the two wires. This additional term leads to a spurious wall-normal velocity signal, resulting in an amplified variance recorded by the cross-wire probe. Compared to the streamwise and wall-normal velocity variances, the Reynolds shear stress ( ) perhaps surprisingly shows less variation when l, and are varied. The robustness of Reynolds shear stress to the finite sensor size is due to two effects: (i) Reynolds shear stress is devoid of energetic contributions from the near-isotropic fine scales unlike the and statistics, hence cross-wire probe dimensions are typically sufficiently small in terms of viscous unit to adequately capture the statistics for a range of l and investigated; (ii) the dependency arises due to cross terms between the filtered velocities from two wires, however, it turns out that these terms cancel one another in the case of Reynolds shear stress, but not for the and statistics. We note that this does not, however, suggest that is easier to measure accurately than the normal stresses; on the contrary, in a companion paper (Baidya et al 2019 Meas. Sci. Technol. 30 085301) we show that measurements are more prone to errors due to uncertainty in probe geometry and calibration procedure
A numerical study of surface air temperature response to vertical mixing and momentum extraction by wind farms and the impacts of wind farms on mesoscale boundaries
No full textWind turbines have been shown to impact their local microclimate. With the increasing areal coverage of wind farms it has become increasingly important to answer scientific questions regarding these impacts. In this thesis, a high resolution numerical model is employed to explore the response of land surface and near surface air temperatures within and in the immediate vicinity of large wind farms in west central Texas to changes in the turbines’ thrust and TKE coefficients during meteorological summers. A control run with no wind turbines is compared to three experimental tests, each with differing thrust and TKE coefficients. The experimental tests are fist compared to observed data from the Moderate Resolution Imaging Spectroradiometer (MODIS) data on the Terra and Aqua Satellites. It is shown that the observed impact of wind farms is greater than the numerically modeled impact. Second, the control run is compared to the experimental tests. The non-linear interaction of hub height wind speeds, thrust coefficients, and TKE coefficients along with the wind turbine layer static stability determine the temperature change impact. During night, statically stable conditions result in strong warming signals while during the day near-neutral conditions result in insignificant impacts. The magnitude of the signal is determined by non-linear interactions between the wind turbines’ thrust coefficient and the vertical wind speed.
The high resolution numerical model is also used to analyze the propagation of mesoscale boundaries near and through the wind farm. When compared to the control run, the experimental simulation shows an acceleration of the propagation of the mesoscale boundaries when the boundaries approached the wind farms and a deceleration as the boundaries propagated away from the wind farms. Due to the reduction of winds by the wind farms, boundaries propagating away from the wind farms experience less winds behind the boundaries and propagation speeds are reduced. Boundaries propagating towards wind farms experience less winds ahead of the wind farms and propagation speeds increase.Item withdrawn by Laura Spradlin ([email protected]) on 2013-12-09T16:36:49Z
Item was in collections:
University of Illinois Theses & Dissertations (ID: 1)
No. of bitstreams: 2
Matthew_Cervarich.docx: 9346494 bytes, checksum: d172153c657ce89b462757a740bc60cd (MD5)
Matthew_Cervarich.pdf: 4038723 bytes, checksum: d290c2e9f0ad1bb2d8a51fa6524495bc (MD5)Made available in DSpace on 2014-01-16T18:17:20Z (GMT). No. of bitstreams: 3
Matthew_Cervarich.pdf: 4038324 bytes, checksum: 4c52a570f1a3c82f46b30be238ab3d36 (MD5)
Matthew_Cervarich.docx: 9346494 bytes, checksum: d172153c657ce89b462757a740bc60cd (MD5)
license.txt: 4067 bytes, checksum: 6ab2f3b702da8dc9ba2b75987ccd8f41 (MD5)Item marked as restricted to the 'UIUC Users [automated]' Group (id=2) by Seth Robbins ([email protected]) on 2014-01-16T18:19:41Z
Item is restricted until 2016-01-16T18:19:34ZRestriction data tranferred 2014-07-01T11:35:38-05:00
Original Data
Group with Access UIUC Users [automated]
Release Date: 2016-01-16 12:19:34 UTC
Reason: Author requested U of Illinois access only (OA after 2yrs) in Vireo ETD systemU of I Only Restriction Lifted for Item 46841 on 2016-01-16T11:02:18Z
The Lipiodol Uterine Bathing Effect to Improve Fertility May Include Uterine Natural Killer Cell Up-regulation in the Endometrium
No full textBackground: Lipiodol has a dramatic short term fertility enhancing effect for women with endometriosis. Microarray studies have shown transcriptomic regulation of molecular markers of endometrial inflammation, most notably a consistent downregulation of endometrial osteopontin. We further explored the endometrial bathing effect of lipiodol on leukocyte expression in endometrium. Methods: A cohort of four women, nested within a randomised trial of twelve women assessing the lipiodol uterine bathing effect, was studied as an ‘own control’ group, with their mid-luteal endometrium assessed before and after endometrial lipiodol exposure. Pipelle endometrial sampling allowed endometrial assessment by immunochemistry. Endometrial tissue samples were assessed by immunochemistry for total CD45+ leukocytes, CD68+ macrophages, CD3+ T-cells and CD56+ uterine natural killer cells. Results: There was a statistically significant increase in the mean density of uterine natural killer cells in the endometrium of women post-lipiodol. No other significant differences were found in the mean densities of all leukocytes, macrophages or T cells in the endometrium of women post-lipiodol. Conclusions: These preliminary data further support the concept of a uterine bathing effect of lipiodol. Whether the increase in the mean density of uterine natural killer cells in the endometrium might contribute to an improvement in endometrial receptivity to embryo implantation merits further investigation.N. P. Johnson, S. Baidya, S. O. Jessup, A. Muthukaruppan, W. E. Hadden, M. L. Hull, S. Mehta, A. N. Shelling, C. G. Print, L. W. Chamle
N-glycosylation induced changes in tau protein dynamics reveal its role in tau misfolding and aggregation: A microsecond long molecular dynamics study
No full textVarious post translational modifications like hyper phosphorylation, O-GlycNAcylation, and acetylation have been attributed to induce the abnormal folding in tau protein. Recent in vitro studies revealed the possible involvement of N–glycosylation of tau protein in the abnormal folding and tau aggregation. Hence in this study, we performed microsecond long all atom molecular dynamics simulation to gain insights into the effects of N-glycosylation on Asn-359residue which forms part of the microtubule binding region. Trajectory analysis of the stimulations coupled with essential dynamics and free energy landscape analysis suggested that tau, in its N-glycosylated form tend to exist in a largely folded conformation having high beta sheet propensity as compared to unmodified tau which exists in a large extended form with very less beta sheet propensity. Residue interaction network analysis of the lowest energy conformations further revealed that Phe378 and Lys353 are the functionally important residues in the peptide which helped in initiating the folding process and Phe378, Lys347&Lys370 helped maintaining the stability of the protein in the folded state
A numerical study of cropland-atmosphere feedbacks by incorporating a crop growth module in the WRF model
No full textThis study investigates cropland-atmosphere feedbacks in the Midwestern United States. Growing crops impact local climate during the growing season by influencing heat, moisture and momentum exchange between the land and the atmosphere. These changes in turn affect the crop growth, thus completing a feedback loop. A computationally efficient modeling tool has been specifically developed to study these feedbacks. A vegetation module derived from a crop growth model SUCROS has been incorporated in the Weather Research Forecasting (WRF) model. This coupled model has the capability to explore cropland-atmosphere feedbacks at a high spatial resolution at mesoscale. Results from soybean fields in Nebraska and Illinois show that the crop growth depends directly on temperature, incoming shortwave radiation and precipitation. As the crops grow, they affect energy partitioning between sensible and latent heat leading to a change in the cloud cover and consequently changing incoming shortwave radiation, air temperature and precipitation. An increase in cloud cover reduces incoming shortwave radiation and hence photosynthesis, exerting a negative feedback. However, an increase in precipitation reduces water stress and promotes growth, resulting in a positive feedback. The net impact on crop growth is a nonlinear combination of these feedbacks.Item withdrawn by Mark Zulauf ([email protected]) on 2012-12-01T17:11:21Z
Item was in collections:
University of Illinois Theses & Dissertations (ID: 1)
No. of bitstreams: 2
Rastogi_Deeksha.docx: 7815489 bytes, checksum: d2785d15c37bf25b7aadf84904e5d7cf (MD5)
Rastogi_Deeksha.pdf: 7798911 bytes, checksum: 181440c8584a6a7d9c13a00121bf8b0a (MD5)Made available in DSpace on 2013-02-03T19:45:58Z (GMT). No. of bitstreams: 3
Deeksha_Rastogi.pdf: 7799436 bytes, checksum: abacff3b4ffed0bbbd192c7cf3e223e3 (MD5)
Rastogi_Deeksha.docx: 7815489 bytes, checksum: d2785d15c37bf25b7aadf84904e5d7cf (MD5)
license.txt: 4065 bytes, checksum: bb98bec824327f630b62a86729e0bb55 (MD5)Restriction data tranferred 2014-07-01T11:35:59-05:00
Original Data
Group with Access Administrator
Release Date: 2015-02-03 13:47:48 UTC
Reason: Author requested closed access (OA after 2yrs) in Vireo ETD systemItem marked as restricted to the 'Administrator' Group (id=1) by Seth Robbins ([email protected]) on 2013-02-03T19:47:54Z
Item is restricted until 2015-02-03T19:47:48ZLimited Restriction Lifted for Item 42396 on 2015-02-03T11:00:31Z
- …
