Engineering Commons^™

Metal-Free Synthesis Of N-Heterocycles Via Intramolecular Electrochemical C-H Aminations, Huiqiao Wang, Yongjun Zheng, Hucheng Xu, Jiaru Zou, Congrui Grace Jin

Department of Civil and Environmental Engineering: Faculty Publications

N-heterocycles are key structural units in many drugs, biologically interesting molecules and functional materials. To avoid the residues of metal catalysts, the construction of N-heterocycles under metal-free conditions has attracted much research attention in academia and industry. Among them, the intramolecular electrochemical C-H aminations arguably constitute environmentally friendly methodologies for the metal-free construction of N-heterocycles, mainly due to the direct use of clean electricity as the redox agents. With the recent renaissance of organic electrosynthesis, the intramolecular electrochemical C-H aminations have undergone much progress in recent years. In this article, we would like to summarize the advances in this research …

Functional Requirements For A Samd14-Capping Protein Complex In Stress Erythropoiesis, Suhita Ray, Linda Chee, Yichao Zhou, Meg A. Schaefer, Michael J. Naldrett, Sophie Alvarez, Nicholas T. Woods, Kyle J. Hewitt

Nebraska Center for Biotechnology: Faculty and Staff Publications

Acute anemia induces rapid expansion of erythroid precursors and accelerated differentiation to replenish erythrocytes. Paracrine signals—involving cooperation between stem cell factor (SCF)/Kit signaling and other signaling inputs—are required for the increased erythroid precursor activity in anemia. Our prior work revealed that the sterile alpha motif (SAM) domain 14 (Samd14) gene increases the regenerative capacity of the erythroid system in a mouse genetic model and promotes stress-dependent Kit signaling. However, the mechanism underlying Samd14’s role in stress erythropoiesis is unknown. We identified a protein-protein interaction between Samd14 and the α- and β-heterodimers of the F-actin capping protein (CP) complex. Knockdown of …

Exploring The Metabolic Landscape Of Pancreatic Ductal Adenocarcinoma Cells Using Genome-Scale Metabolic Modeling, Mohammad Mazharul Islam, Andrea Goertzen, Pankaj K. Singh, Rajib Saha

Department of Chemical and Biomolecular Engineering: Faculty Publications

Pancreatic ductal adenocarcinoma (PDAC) is a major research focus because of its poor therapy response and dismal prognosis. PDAC cells adapt their metabolism to the surrounding environment, often relying on diverse nutrient sources. Because traditional experimental techniques appear exhaustive to find a viable therapeutic strategy, a highly curated and omics-informed PDAC genome-scale metabolic model was reconstructed using patient-specific transcriptomics data. From the model-predictions, several new metabolic functions were explored as potential therapeutic targets in addition to the known metabolic hallmarks of PDAC. Significant downregulation in the peroxisomal beta oxidation pathway, flux modulation in the carnitine shuttle system, and upregulation in …

Gross Positioning Device And Related Systems And Methods, Mark A. Reichenbach, Shane M. Farritor

Department of Mechanical and Materials Engineering: Faculty Publications

Disclosed herein are gross positioning systems for use with robotic surgical devices to provide gross positioning of the robotic surgical devices. The gross positioning systems have a base, a first arm link operably coupled to the base, a second arm link operably coupled to the first arm link, a third arm link operably coupled to the second arm link, and a slidable coupling component slidably coupled to the third arm link.

Halide Perovskites Enable Polaritonic Xy Spin Hamiltonian At Room Temperature, Renjie Tao, Kai Peng, Louis Haeberlé, Quanwei Li, Dafei Jin, Graham R. Fleming, Stéphane Kéna-Cohen, Xiang Zhang, Wei Bao

Department of Electrical and Computer Engineering: Faculty Publications

Exciton polaritons, the part-light and part-matter quasiparticles in semiconductor optical cavities, are promising for exploring Bose–Einstein condensation, non-equilibrium many-body physics and analogue simulation at elevated temperatures. However, a room-temperature polaritonic platform on par with the GaAs quantum wells grown by molecular beam epitaxy at low temperatures remains elusive. The operation of such a platform calls for long-lifetime, strongly interacting excitons in a stringent material system with large yet nanoscale-thin geometry and homogeneous properties. Here, we address this challenge by adopting a method based on the solution synthesis of excitonic halide perovskites grown under nanoconfinement. Such nanoconfinement growth facilitates the synthesis …

Axial Hypersensitivity Is Associated With Aberrant Nerve Sprouting In A Novel Model Of Disc Degeneration In Female Sprague Dawley Rats, David J. Lillyman, Fei San Lee, Evie C. Barnett, Tyler J. Miller, Moreno Lozano Alvaro, Henry C. Drvol, Rebecca A. Wachs

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Chronic low back pain is a global socioeconomic crisis and treatments are lacking in part due to inadequate models. Etiological research suggests that the predominant pathology associated with chronic low back pain is intervertebral disc degeneration. Various research teams have created rat models of disc degeneration, but the clinical translatability of these models has been limited by an absence of robust chronic painlike behavior. To address this deficit, disc degeneration was induced via an artificial annular tear in female Sprague Dawley rats. The subsequent degeneration, which was allowed to progress for 18-weeks, caused a drastic reduction in disc volume. Furthermore, …

Tracing Geochemical Sources And Health Risk Assessment Of Uranium In Groundwater Of Arid Zone Of India, P. Pandit, Atul Saini, Sabarathinam Chidambaram, Vinod Kumar, Banjarani Panda, A. L. Ramanathan, Netrananda Sahu, A. K. Singh, Rohit Mehra

Nebraska Water Center: Faculty Publications

Water quality degradation and metal contamination in groundwater are serious concerns in an arid region with scanty water resources. This study aimed at evaluating the source of uranium (U) and potential health risk assessment in groundwater of the arid region of western Rajasthan and northern Gujarat. The probable source of vanadium (V) and fluorine (F) was also identified. U and trace metal concentration, along with physicochemical characteristics were determined for 265 groundwater samples collected from groundwater of duricrusts and palaeochannels of western Rajasthan and northern Gujarat. The U concentration ranged between 0.6 and 260 μg L⁻¹ with a mean …

Evaluation Of An Equivalent Mean Grain Size Diameter To Rationally Predict The Erodibility Of Fine Riverbed Soils In Nebraska, Basil Abualshar

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

The erosion of riverbed soils under the bridges is one of the major reasons that cause bridge closure or failure leading to a significant effect on the local economy. One of the commonly used methods to predict the erosion rate of soils is the excess shear stress method, which is based on two parameters describing the erodibility behavior; the erodibility coefficient and the critical shear stress. On the other hand, studies showed that the mean grain size diameter D₅₀ could be correlated to the erosion resistance of soils, usually for cohesionless soils but not for cohesive soils. It is …

Outdoor Laboratory And Testbed For Bridge Health, Richard L. Wood, Mitra Nasimi, Bowen Yang, Christine E. Wittich, Joshua Steelman, Jay Puckett, Daniel Linzell, Jinying Zhu, Mohammad Ebrahim Mohammadi

Nebraska Department of Transportation: Research Reports

Due to the aging problem of bridges and the limited financial resources in the United States, it is necessary to form a deeper understanding of existing, aging bridges in an effort to extend their in-service life. To address this problem, researchers from the University of Nebraska-Lincoln (UNL) and engineers from the Nebraska Department of Transportation (NDOT) identified three, out-of-service bridges (two steel and one concrete) to establish the Nebraska Outdoor Bridge Lab (NOBL). As the first step in NOBL’s development, geometric surveys of the current condition of each bridge were produced using lidar and Structure-from-Motion (SfM). This data contributed to …

Data-Driven Prioritization And Empirical Predictions For Bridge Scour In Nebraska, Richard L. Wood, Awgku Ahmad Hashim B. Awg Bolhasan, Basil Abualshar, Christine E. Wittich, Chung R. Song, Junke Guo, Mohammad Ebrahim Mohammadi, Mitra Nasimi, Yijun Liao

Nebraska Department of Transportation: Research Reports

The effect of scour at the bridge substructure results in an increase in the vulnerability of the overall bridge stability. Previous studies have found that current guidelines are often overly-conservative with respect to scour. This project aims to provide guidance on hydraulic modeling parameters and reasonable scour estimates specific to Nebraska conditions. This will enable engineers to assess bridge sites for scour more precisely for efficient and effective design and countermeasures. Four sites were surveyed for scour changes between the period of December 9, 2020, to April 20, 2021. At these four sites, overland and bathymetry survey data were collected. …

Single-Pass Inline Pipeline 3d Reconstruction Using Depth Camera Array, Zhexiong Shang, Zhigang Shen

Department of Construction Engineering and Management: Faculty Publications

A novel inline inspection (ILI) approach using depth cameras array (DCA) is introduced to create high-fidelity, dense 3D pipeline models. A new camera calibration method is introduced to register the color and the depth information of the cameras into a unified pipe model. By incorporating the calibration outcomes into a robust camera motion estimation approach, dense and complete 3D pipe surface reconstruction is achieved by using only the inline image data collected by a self-powered ILI rover in a single pass through a straight pipeline. The outcomes of the laboratory experiments demonstrate one-millimeter geometrical accuracy and 0.1-pixel photometric accuracy. …

Rechargeable Multi-Cell Battery, Wei Qiao, Taesic Kim, Liyan Qu

Department of Electrical and Computer Engineering: Faculty Publications

A method for power management of a multi - cell battery includes identifying a desired power value and voltage value , determining a battery voltage value and a battery current value for a battery , determining a number of battery banks from a plurality of battery banks to use for the battery , where each battery bank includes one or more battery cells ( or battery modules ) , checking availability of each of the one or more battery cells ( or battery modules ) , selecting one or more battery banks from the plurality of battery banks , where …

Monolithic Integration Of Hybrid Perovskite Single Crystals With Silicon For Highly Sensitive X - Ray Detectors, Jinsong Huang, Wei Wei

Department of Mechanical and Materials Engineering: Faculty Publications

Perovskite single crystal X - ray radiation detector devices including an X - ray wavelength - responsive active layer including an organolead trihalide perovskite single crystal, a substrate layer comprising an oxide, and a binding layer disposed between the active layer and the substrate layer. The binding layer including a binding molecule having a first functional group that bonds to the organolead trihalide perovskite single crystal and a second functional bonds with the oxide. Inclusion of the binding layer advantageously reduces device noise while retaining signal intensity.

A High-Density Theta Burst Paradigm Enhances The Aftereffects Of Transcranial Magnetic Stimulation: Evidence From Focal Stimulation Of Rat Motor Cortex, Qinglei Meng, Hieu Nguyen, Antonia Vrana, Simone Baldwin, Charlotte Qiong Li, Antonia Giles, Jun Wang, Yihong Yang, Hanbing Lu

Department of Electrical and Computer Engineering: Faculty Publications

Background: Theta burst stimulation (TBS) is an efficient noninvasive neuromodulation paradigm that has been widely adopted, clinically. However, the efficacy of TBS treatment remains similarly modest as conventional 10 Hz repetitive transcranial magnetic stimulation (rTMS).

Objective/hypothesis: To develop a new TBS paradigm that enhances the effects of TMS administration while maintaining high time-efficiency.

Methods: We describe here a new TMS paradigm, named High-Density Theta Burst Stimulation (hdTBS). This paradigm delivers up to 6 pulses per burst, as opposed to only 3 in conventional TBS, while maintaining the inter-burst interval of 200 ms (or 5 Hz) - a …

Assessing The Effectiveness Of Problem-Based Learning Across Two Concrete Construction Courses, Anthony Torres, Jiong Hu, Vedaraman Sriraman, Araceli Martínez-Ortiz, Jorge Membrillo-Hernández

Department of Civil and Environmental Engineering: Faculty Publications

The goal of this study is to assess the effectiveness of a Problem-Based Learning (PBL) pedagogy that was implemented in two different concrete construction courses. Both courses are a part of an industry focused four-year undergraduate concrete degree program. One of the classes focused on concrete problems, diagnosis, and repair of existing concrete, while the other class focused on handling and management methods of various concrete mixtures. In both courses, a PBL pedagogy was implemented such that students were self-learning and discovering the knowledge through an action-research case study. The action-research case study was specific to the course outcomes relevant …

A Segmentation-Guided Deep Learning Framework For Leaf Counting, Xijian Fan, Rui Zhou, Tardi Tjahjadi, Sruti Das Choudhury, Qiaolin Ye

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Deep learning-based methods have recently provided a means to rapidly and effectively extract various plant traits due to their powerful ability to depict a plant image across a variety of species and growth conditions. In this study, we focus on dealing with two fundamental tasks in plant phenotyping, i.e., plant segmentation and leaf counting, and propose a two-steam deep learning framework for segmenting plants and counting leaves with various size and shape from two-dimensional plant images. In the first stream, a multi-scale segmentation model using spatial pyramid is developed to extract leaves with different size and shape, where the fine-grained …

Towards A Cybersecurity Testbed For Agricultural Vehicles And Environments, Mark Freyhof, George Grispos, Santosh Pitla, Cody Stolle

Department of Agricultural and Biological Systems Engineering: Faculty Publications

In today’s modern farm, an increasing number of agricultural systems and vehicles are connected to the Internet. While the benefits of networked agricultural machinery are attractive, this technological shift is also creating an environment that is conducive to cyberattacks. While previous research has focused on general cybersecurity concerns in the farming and agricultural industries, minimal research has focused on techniques for identifying security vulnerabilities within actual agricultural systems that could be exploited by cybercriminals. Hence, this paper presents STAVE – a Security Testbed for Agricultural Vehicles and Environments – as a potential solution to assist with the identification of cybersecurity …

Passivation Of Defects In Perovskite Materials For Improved Solar Cell Efficiency And Stability, Jinsong Huang, Xiaopeng Zheng

Department of Mechanical and Materials Engineering: Faculty Publications

Semiconductor devices , and methods of forming the same , include a cathode layer , an anode layer , and an active layer disposed between the cathode layer and the anode layer , wherein the active layer includes a perovskite layer . A passivation layer is disposed directly on a surface of the active layer between the cathode layer and the active layer , the passivation layer including a layer of material that passivates both cationic and anionic defects in the surface of the active layer .

Intelligent Work Zone Using Automatic Queue Detection Systems, Li Zhao, Laurence Rilett, Ernest Tufuor

Nebraska Department of Transportation: Research Reports

This report documents the the evaluation of the effectiveness of the Advanced Queue Detection (AQD) systems installed on Interstate work zones in Nebraska. Specifically, (1) the system performance was verified by examining whether the messages displayed on the portable dynamic message signs (PDMS) were consistent with the underlying AQD logic; (2) the system efficacy was measured by determining whether driver speeds were reduced when warning messages were provided on the PDMS; and (3) the system safety impact was modeled using statistical models. It was found that overall, the AQD systems had an error rate of 0.7% – 2.3%. Drivers reduced …

Sprouting Systems, Abaigeal Aydt, Cassidy Smith

Honors Program: Expanded Learning Clubs

After taking a class at UNL about environmental awareness, two honors students paired up to start a hydroponics club at a local Lincoln school. In reaching out to the LPS director of sustainability, they were paired up with Prescott Elementary School. Over the course of a semester, they developed a club that got a hydroponic grow tower functioning for the school and taught students about nutrition and sustainability. This club is only in its beginning stages, but the impacts that it is making around the school can already be seen.

Real Time Audio Processing Using A Low-Power Digital Signal Processor, Aaron Norlinger

Honors Program: Senior Projects (Public)

This project focused on the creation of a series of audio processing functions that could run in real time on the ezDSP5502 processor. The Digital Signal Processor (DSP) being used for this project is an industry standard for lowpower signal processing applications. The overall goal was to have a code base that could sample audio in real time from any source, filter it in a variety of ways, run a Fast Fourier Transform on the audio, display the resulting frequency data to an LCD screen, and then output the filtered audio to an external speaker. This general process is used …

Molecular-Level Control Over Ionic Conduction And Ionic Current Direction By Designing Macrocycle-Based Ionomers, Shyambo Chatterjee, Ehsan Zamani, Seefat Farzin, Iman Evazzade, Oghenetega Allen Obewhere, Tyler James Johnson, Vitaly Alexandrov, Shudipto Konika Dishari

Department of Chemical and Biomolecular Engineering: Faculty Publications

Poor ionic conductivity of the catalyst-binding, submicrometer- thick ionomer layers in energy conversion and storage devices is a huge challenge. However, ionomers are rarely designed keeping in mind the specific issues associated with nanoconfinement. Here, we designed nature-inspired ionomers (calix-2) having hollow, macrocyclic, calix[4]arene-based repeat units with precise, sub-nanometer diameter. In ≤100 nm-thick films, the in-plane proton conductivity of calix-2 was up to 8 times higher than the current benchmark ionomer Nafion at 85% relative humidity (RH), while it was 1−2 orders of magnitude higher than Nafion at 20−25% RH. Confocal laser scanning microscopy and other synthetic techniques allowed us …