51 research outputs found
DATASET: Results from Cyclic Tests of Earthquake-Resistant Rectangular Walls with Mechanically-Spliced High-Strength Reinforcement
No full textThis dataset contains results of the tests reported in the following:
Neupane, U., Lequesne, R. D., Lepage, A., and Darwin, D., 2025, Mechanically-Spliced High-Strength Steel Bars in Earthquake-Resistant Walls, SM Report No. 165, The University of Kansas Center for Research, Inc., Lawrence, KS. https://hdl.handle.net/1808/35869This dataset includes results from tests of three reinforced-concrete walls with mechanical splices at the base under reversed cyclic lateral displacements. Details of the specimens are reported in Neupane et al. (2025). The reported data include drift ratio, lateral force (of each actuator), lateral wall displacement at the elevation of the actuator (called “P6_HL_WS10”), reinforcement strain, 3D coordinates of optical (Optotrak) markers on the bottom 100 in. of the wall, and the total lateral force. The data are provided in separate text files for each of the three specimens. An “Instrumentation Details” file is also provided that shows the location and naming scheme for each of the instruments
DATASET: Results from Cyclic Tests of Reinforced Concrete Column-Foundation Connections
No full textThis dataset contains results of the tests reported in the following:
Niyonyungu, F., Lequesne, R. D., Lepage, A., and Darwin, D., 2024, Deformation Capacity of Reinforced Concrete Column-to-Foundation Connections with Anchorage/Breakout Failures, SM Report No. 161, The University of Kansas Center for Research, Inc., Lawrence, KS, 182 pp., https://hdl.handle.net/1808/35517
Neupane, U., Lequesne, R. D., Lepage, A., and Darwin, D., 2024, Behavior of Earthquake-Resistant Reinforced Concrete Column-Foundation Connections, SM Report No. 162, The University of Kansas Center for Research, Inc., Lawrence, KS, 250 pp., https://hdl.handle.net/1808/35578This dataset includes results from tests of six reinforced-concrete column-foundation connections under fully-reversed cyclic lateral displacements. Details of the specimens are reported in Niyonyungu et al. (2024) and Neupane et al. (2024). The reported data include drift ratio, lateral force, lateral column displacement at the elevation of the actuator (called “LVDT”), reinforcement strain, and the 3D coordinates of optical (Optotrak) markers on the surface of the specimens. The data are provided in separate text files for each of the six specimens. An “Instrumentation Details” file is also provided that shows the location and naming scheme for each of the instruments
Probing surface protein patterning in biological systems using fluorescence nanoscopy
No full textA complete understanding of biological substructures is often obscured by the diffraction limit of visible light in conventional fluorescence microscopy. Recently developed fluorescence nanoscopy techniques such as stochastic optical reconstruction microscopy (STORM) effectively break the diffraction limit (~250 nm) to enable imaging with an order of magnitude smaller than the spatial resolution. In this work, we applied fluorescence nanoscopy to study the patterning of proteins in biological surfaces at a high spatial resolution of 25 nm. We also developed new analytical methods to extract quantitative information on protein arrangement within biological substrates to elucidate key phenomenon such as signal amplification in bacteria during chemotaxis. In B. subtilis, we observed reorganization in arrays of McpB receptor proteins, key chemotactic receptors for asparagine sensing, upon exposure to saturating stimulant concentrations. More specifically, receptors formed large polar clusters in the absence of stimulant but shifted towards smaller and more dispersed lattices throughout the cell when stimulant was added. In a first-of-its-kind fluorescence nanoscopic study on B. subtilis, we measured cluster sizes and intra cluster density of these receptors. Our results support the existing theories on the role of cooperativity via receptor clustering in signal amplification to respond to wide range of external stimuli in bacteria. In second project, we studied the role of viral proteins on HIV-1 infectivity. In HIV-1, envelope proteins gp120 and gp41 are known to play a significant role in infectivity and their arrangement is indicative of internal viral structure at different stages of its life cycle. We ascertained the distribution of both the envelope proteins on surface of virions at a high resolution of ~25 nm using three-color fluorescence nanoscopy. Our work effectively paves the way for revealing new levels of organization of surface proteins at nanometer scale spatial resolution for a molecular view understanding of dynamics in biological systems.Submission published under a 24 month embargo labeled 'Closed Access', the embargo will last until 2017-08-01The student, Utsav Agrawal, accepted the attached license on 2015-07-09 at 15:02.The student, Utsav Agrawal, submitted this Dissertation for approval on 2015-07-09 at 15:03.This Dissertation was approved for publication on 2015-07-10 at 08:51.DSpace SAF Submission Ingestion Package generated from Vireo submission #8391 on 2015-09-29 at 15:05:53Made available in DSpace on 2015-09-29T21:03:10Z (GMT). No. of bitstreams: 2
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Quality of life among people living with acquired immune deficiency syndrome receiving anti-retroviral therapy: a study from Nepal
No full textSmith Giri, Maniraj Neupane, Sushil Pant, Utsav Timalsina, Sagar Koirala, Santosh Timalsina, Sashi Sharma Department of Medicine, Tribhuvan University Teaching Hospital, Kathmandu, Nepal Purpose: The present study was undertaken to determine the impact of acquired immune deficiency syndrome (AIDS) on the quality of life of affected individuals in Nepal. Patients and methods: A cross sectional study was done among 70 individuals attending the Anti-Retroviral Therapy clinic of the University Hospital in Nepal. Quality of life (QOL) was evaluated using World Health Organization Quality of life questionnaire (WHO QOL-BREF) instrument. Statistical analysis was done using SPSS Version 17.0. Results: The median scores with interquartile range (IQR) in four domains of QOL in descending order were physical (61; IQR 22), social (58; IQR 33), environmental (56; IQR 13), and psychological (54; IQR 8). Older age was associated with lower perceived overall QOL. Females were more likely to have lower QOL scores in the social and psychological domains. Higher CD4 counts and a married status were significant predictors of higher QOL scores in the environmental domain. Conclusion: Being older, female, single, and having advanced clinical stage is associated with lower QOL scores in people living with AIDS. Lowest QOL scores were seen in the psychological domain suggesting the need of psychological interventions. Keywords: quality of life, AIDS, Nepal, WHO QOL-BRE
Energy-efficient protocols and hardware architectures for transport layer security
No full textThesis: S.M., Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science, 2017.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.Cataloged from student-submitted PDF version of thesis.Includes bibliographical references (pages 99-104).The Internet of Things (IoT) has introduced a vision of an Internet where computing and sensing devices are interconnected. Digitally connected devices are encroaching on every aspect of our lives, including our homes, cars, offices, and even our bodies. Researchers estimate that there will be over 50 billion wireless connected devices by 2020 [1]. On one hand, the IoT enables fundamentally new applications, but on the other, these devices are attractive targets for cyber attackers, thus making IoT security a major concern. Datagram Transport Layer Security (DTLS) is considered to be one of the most suited protocols for securing the IoT. However, computation and communication overheads make it very expensive to implement DTLS on resource-constrained IoT sensor nodes. In this work, we profile the energy costs of DTLS version 1.3, using experimental models for cryptographic computations and radio-frequency (RF) communications. Based on this analysis, we propose protocol optimizations that can reduce the overall energy consumption of DTLS up to 45%, while still maintaining the same security strength of the standard DTLS. We discuss energy-efficient architectures for implementing the standard cryptographic primitives AES (Advanced Encryption Standard), SHA (Secure Hash Algorithm) and ECC (Elliptic Curve Cryptography) in hardware. Our hardware can provide more than 2,500 times reduction in energy consumption compared to traditional software implementations. These hardware primitives are integrated with dedicated control and memory to design a DTLS co-processor that can accelerate the complete DTLS state machine in hardware, thus minimizing the energy consumption due to DTLS computations. The proposed DTLS core is integrated with a RISC-V micro-processor to accurately profile these functions, as well as design custom protocols using standalone cryptographic instructions.by Utsav Banerjee.S.M
Behavior of Earthquake-Resistant Reinforced Concrete Column-Foundation Connections
No full textResults from these tests can be found at this reference:
Neupane, U., Niyonyungu, F., Lequesne, R. D., Lepage, A., and Darwin, D., DATASET: Results from Cyclic Tests of Reinforced Concrete Column-Foundation Connections, KU Scholarworks, Lawrence, KS, January 2025. https://hdl.handle.net/1808/35803Reversed-cyclic tests of large-scale reinforced concrete column-foundation connections with hooked column longitudinal bars were performed to investigate the mechanisms of moment-transfer and breakout failure. Two tests were conducted and then analyzed in combination with results from four tests reported in Niyonyungu (2024) and one test reported in Chen (2021). The columns were 2-ft (605 mm) square and longitudinally-reinforced with 12 or 16 No. 8 (25 mm) bars. Other variables included column hooked-bar embedment length (15 or 19 times the column bar diameter), foundation thickness (18 or 30 in. (460 or 760 mm)), the presence or absence of foundation shear reinforcement, and foundation flexural reinforcement (No. 6 (19 mm) bars spaced at 5.5, 9, or 12 in. (140, 225, or 300 mm) in two directions). The nominal concrete compressive strength was 6000 psi (42 MPa) and reinforcement was Grade 60 (420).
Test results show that specimen strength was limited by column bar yielding and drift ratio capacity was governed by breakout. Results show that, for connections like those tested, drift ratio increases when either: a) column longitudinal bar yield strain penetration from the top of the foundation to the onset of the bends is delayed, or b) breakout resistance is increased. Increased foundation longitudinal reinforcement ratio and longer column bar embedment both delayed yielding at the onset of the column-bar bend and correlated with greater drift ratio capacity. Providing foundation shear reinforcement with shear strength exceeding 40% of the transfer moment based on the eccentric shear stress model, ignoring the concrete contribution, was shown to delay breakout and increase drift ratio capacity. The top mat of foundation reinforcement participated more in resisting transfer moment than implied by a strength model based on equal participation of top and bottom mats, indicating the top mat of reinforcement should be designed for the full transfer moment instead of splitting the reinforcement between top and bottom mats. Top mat strains, which were much more sensitive to column bar embedment length than to foundation depth, were largest within the column width and decreased as the distance from the column face increased up to approximately 1.5 times the column hooked-bar embedment length, suggesting that the concept of a transfer width is useful for designing foundations for column moment transfer. Taken together with the observation that top mat strains were more affected by column hooked-bar embedment length than foundation thickness, the definition of transfer width for moment transfer calculations should based on column bar embedment length.The Electric Power Research Institut
Mechanically-Spliced High-Strength Steel Bars in Earthquake-Resistant Walls
No full textResults from these tests can be found at this reference:
Neupane, U., Lequesne, R. D., Lepage, A., and Darwin, D., DATASET: Results from Cyclic Tests of Earthquake-Resistant Rectangular Walls Mechanically-Spliced High-Strength Reinforcement, KU Scholarworks, Lawrence, KS, January 2025. https://hdl.handle.net/1808/35804Three large-scale reinforced concrete rectangular slender structural walls were subjected to reversed-cyclic displacement demands to investigate the use of mechanical splices with Grade 100 (690) longitudinal bars in regions where yielding is expected. These tests were undertaken because ACI 318-19 prohibits both lap and mechanical splices for Grade 100 (690) bars in special structural walls where longitudinal reinforcement yielding is likely. The reinforcement detailing of the walls satisfied ACI 318-19 requirements for special structural walls, except that all longitudinal bars of the walls each had one of three types of mechanical splices located 2 in. (50 mm) from the top of foundation. The mechanical splice types considered were: taper-threaded, swaged-threaded, and shear screwed. The impact of the mechanical splice on wall cracking, surface strains, bar strain demands, drift ratio capacity, and failure mode are examined.
All three walls reached the same deformation capacity (at least one cycle to 3% drift ratio) irrespective of the splice connection type or length but differed in the failure mode, with Wall 1 losing strength due to bar fractures. Mechanical splices with a strength not less than the actual bar tensile strength, such that bars systematically fail in direct tension tests away from the splice, performed well. Such bar failure in direct tension tests should be required of mechanical splices used where yielding is expected. Mechanical splices satisfying ACI 318-19 Type 2 criteria resulted in better wall behavior than reported for lap splices, but bar fractures still occurred at the splice, so Type 2 splice requirements alone are insufficient to allow mechanical splices where yielding is expected.
Splice length influenced crack distribution near the splices and wall failure mode. The taper-threaded splices (length 0.1*l_w) led to more concentrated cracks above the splices. The concentrated cracking led to larger longitudinal and shear strains (> 0.01 radians) measured on the concrete surface at larger drifts, resulting in shear-induced compression failures of those walls. Although the maximum shear force remained relatively constant after 1% drift ratio, average shear surface strain in a row-layer near the base of all three specimens continued to increase nearly proportionally to the average longitudinal surface strains in the same row-layer. Further study is necessary to examine whether average longitudinal and shear strains remain proportional as wall configuration and loading conditions change.
A simple model was proposed for relating bar strains to wall drift ratio that estimated boundary element longitudinal bar strains that were nearly within 10% of the measured values at 2% and 2.5% drift ratio for the walls tested in this study. A parametric study conducted with the model suggests that for a given drift demand, bar strain demands increase as splice length increases and as splice relative elongation, wall aspect ratio, reinforcement grade, and longitudinal bar diameter decrease. The contribution of shear distortion to overall drift and concrete compressive strength have relatively small effects on calculated bar strain demands. Based on the test results and parametric study, it is recommended to limit mechanical splice length to 0.2*l_w at the base of slender walls with Grade 100 (690) longitudinal reinforcement.
Appendix E reports preliminary results from an investigation of squat wall strength. No conclusions are drawn based on the results presented.Electric Power Research Institut
Sedimentation and viscosity controls on forearc high growth
No full text23 pages, 12 figures, 2 tables, supplementary material https://doi.org/10.1111/bre.12518.-- The data that support the findings of this study are available from the corresponding author upon reasonable request..-- This is the pre-peer reviewed version of the following article: David Fernández‐Blanco, Utsav Mannu, Teodoro Cassola, Giovanni Bertotti, Sean D. Willett; Sedimentation and viscosity controls on forearc high growth; Basin Research 33(2): 1384-1406 (2021), which has been published in final form at https://doi.org/10.1111/bre.12518. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived VersionsCrustal rheology and surface processes strongly influence strain distribution and shape of orogenic wedges at their front but how they influence the wedge rear is still unclear. Here, we analyse the coupled control of viscosity and sedimentation on forearc high growth during advanced stages of subduction accretion. We use 2D thermo‐mechanical finite element models constrained with data of the south Anatolian margin. Our simulations show that forearc highs grow as a thermally‐activated viscosity drop in the lower crust induces ductile deformation and viscous flow. Initial viscosity and the amount of sediments in the forearc basin control non‐linearly the occurrence and timing of the thermally‐activated viscosity drop, and thus of the growth of the forearc high. High sedimentation rates result in thicker forearc basins that stabilise the subduction wedge and delay the onset of uplift in the forearc high. Low viscosities promote earlier onset of forearc high uplift and lead to larger morphological variability along the subduction margin. Increasing either the sedimentation rate or viscosity may prevent forearc high formation entirely. The thermo‐viscous forearc highs grow at an age set by wedge thermal state as a function of accretionary flux, wedge viscosity, and synorogenic sedimentation. Our models explain vertical motions in south Anatolia and potentially in other accretionary margins, like the Lesser Antilles or Cascadia, during the formation of their broad forearc highsWith the funding support of the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000928-S), of the Spanish Research Agency (AEI)Peer reviewe
Forearc high uplift by lower crustal flow during growth of the Cyprus-Anatolian margin
No full textWe present a model for the dynamic formation of the forearc high of southern Anatolia where sedimentation in the forearc basin leads to thermally-activated deformation in the lower crust. Our thermo-mechanical models demonstrate that forearc sedimentation increases the temperature of the underlying crust by “blanketing” the heat flux and increasing Moho depth. Deformation switches from frictional to viscous with a higher strain rate led by increased temperature. Viscous deformation changes large-wavelength subsidence into coeval, short-wavelength uplift and subsidence. Models show that forearc highs are intrinsic to accretionary wedges and can grow dynamically and non-linearly at rates dependent on sediment accretion, sedimentation and temperature. The mechanism explains the uplift of the southern margin of the Central Anatolian Plateau and the Neogene vertical motions and upper-plate strain in the Anatolian margin along Central Cyprus. This system is analogous to forearc highs in other mature accretionary margins, like Cascadia, Lesser Antilles or Makran.Accepted Author ManuscriptApplied Geolog
Waxol and Chitosan Coatings to Extend Tomato Shelf-Life
No full textThis Dissertation / Report is the outcome of investigation carried out by the creator(s) / author(s) at the department/division of Central Food Technological Research Institute (CFTRI), Mysore mentioned below in this page
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