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APG Method for Energy-Efficient Power Control in Cell-Free Massive MIMO with Zero-Forcing

2020 IEEE Eighth International Conference on Communications and Electronics (ICCE), 2021

In this work, we consider a cell-free massive multiple-input multiple-output (MIMO) downlink with... more In this work, we consider a cell-free massive multiple-input multiple-output (MIMO) downlink with zero-forcing processing. We propose to design a power allocation algorithm that maximizes the system energy efficiency (EE) taking into account imperfect channel state information, backhaul and hardware power consumption. The total EE problem is non-convex and is normally solved by successive approximation technique in the related literature. Such methods approximate a nonconvex problem by a sequence of standard convex programs, and thus require prohibitively long run time, especially when the system has thousands of access points (APs), and hundreds of users. To derive a computationally efficient algorithm, in this paper, we apply an accelerated proximal gradient (APG) method to solve the considered problem. Numerical results show that with a cell-free massive MIMO system using hundreds of APs and tens of users, compared to the conventional second order cone programs (SOCPs) successive approximation technique, our proposed method achieves the same performance with around 100 times faster.

VXI implementation of a millimeter wave measurement system

1993 IEEE Instrumentation and Measurement Technology Conference

A measurement system was developed to provide integrated signal generation and noise measurement ... more A measurement system was developed to provide integrated signal generation and noise measurement capability for the W-band frequency range, 75-110 GHz. An architecture conforming to established VXI technology was chosen for the implementation. The implementation consisted of integrating commercially available message-based VXI instruments, developing a unique module to provide W-band signal generation and downconversion capability that conformed to VXI specification,

Advanced technologies in molecular and wireless communication networks : analysis, design, and optimisation

Communication networks have vital roles in our daily lives, both in small-scale and large-scale p... more Communication networks have vital roles in our daily lives, both in small-scale and large-scale perspective. First, in small-scale networks, nanonetworks consisting of nano-scale devices have been proposed to solve problems in environmental monitoring, healthcare (in the form of nanomedicine), industrial, and military fields. An emerging means of supporting communication between nano-scale devices is molecular communication (MC), where information is encoded in the type, quantity or timing of molecules released by a transmitter. These molecules are then either carried, drift, or diffuse from the transmitter to a receiver, where decoding can take place. In the large-scale networks, with the exponential growth of the data traffic and the massive increase in the number of connected devices in the age of Internet-ofThings (IoT), future wireless communication networks have to satisfy some main requirements, such as a capability of serving many devices simultaneously, providing high per-u...

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Affinity Orientation in Employment and Labor Law

This research project was to create a Weblog to serve as a resource for students in the Business ... more This research project was to create a Weblog to serve as a resource for students in the Business Law 452 class and was designed in conjunction with MSU\u27s LGBTQQA (lesbian, gay, bisexual, transgender, queer, questioning, and allied individuals) center during the Spring 2006 semester. After conclusion of the class, the blog will be maintained and updated by the LGBTQQA center for their use in communicating with the LGBTQQA and MSU communities. This blog has served as a forum for discussion and resolution of issues in our campus community. We have created the foundation for a service learning project with the LGBTQQA center on campus, focusing on affinity orientation in the workplace, government institutions, and educational facilities. Our resources, with the assistance of the LGBT center, have included documentaries, legal websites, personal interviews, and other resources. This blog was styled to be an open communication forum. Any person could write to the blog editor in the question box, and all inquiries have been answered within 48 hours. We welcomed any other resources or contributions. In the long term, we hope this blog will become an asset to Minnesota State University. Our priority in creating and developing this blog was not only for one class, but as an outreach to the entire MSU population

Cedar County Comprehensive Plan for 2038

Priorities in implementing this Plan were developed from community engagement, steering committee... more Priorities in implementing this Plan were developed from community engagement, steering committee input, American Planners Association best practices, and Iowa Smart Planning guidance. The components with the highest priority feature critical goals that supports the Comprehensive Plan's mission. Chapter 1-Introduction 2035 Comprehensive Plan: A Vision for Cedar County The 2018 Cedar County Comprehensive Plan was developed to help guide the future growth and development of Cedar County for the next 10 to 20 years. The plan addresses land use, housing, economic development, transportation and infrastructure, natural resources, recreation and quality of life. 10. Transportation diversity in the expansion or maintenance of transportation systems.

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Coexistence in molecular communications

Nano Communication Networks, 2018

Molecular communications is emerging as a technique to support coordination in nanonetworking, pa... more Molecular communications is emerging as a technique to support coordination in nanonetworking, particularly in biochemical systems. In complex biochemical systems such as in the human body, it is not always possible to view the molecular communication link in isolation as chemicals in the system may react with chemicals used for the purpose of communication. There are two consequences: either the performance of the molecular communication link is reduced; or the molecular link disrupts the function of the biochemical system. As such, it is important to establish conditions when the molecular communication link can coexist with a biochemical system. In this paper, we develop a framework to establish coexistence conditions based on the theory of chemical reaction networks. We then specialize our framework in two settings: an enzyme-aided molecular communication system; and a low-rate molecular communication system near a biochemical system. In each case, we prove sufficient conditions to ensure coexistence.

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A treatment strategy for KRAS-driven tumors

Nature medicine, 2018

by α-syn aggregates. Unraveling this interplay will have great clinical relevance. Second, the re... more by α-syn aggregates. Unraveling this interplay will have great clinical relevance. Second, the results provide tentative insight into the mechanisms underlying the positive results in the two clinical trials using GLP-1R agonists to treat patients with PD. Perhaps future studies using measures of neuroinflammation (such as by in vivo brain imaging or biomarkers in cerebrospinal fluid) can determine whether GLP-1R agonists reduce neuroinflammation in PD. Such studies need only last a few weeks or months, potentially using a crossover design assessing clinical outcome measures and inflammatory mediators in the same patients. Third, the results showing that a GLP-1R agonist reduces activation of microglia and astrocytes might explain the recently reported improvements in nonmotor symptoms in patients with PD treated with exenatide. Proinflammatory cytokines can induce depressive symptoms through direct actions on neuronal cytokine receptors and downstream effects on monoamine metabolism, as well as via formation of inflammatory metabolites affecting glutamate neurotransmission 13. Thus, activated microglia might contribute to nonmotor symptoms of PD, and therefore, GLP-1R agonists may mitigate mood disorders in PD independently of any effects on neurodegeneration by reducing formation of proinflammatory cytokines from microglia. The study by Yun et. al. 3 is an exciting development that should trigger more research into how GLP-1R agonists might alleviate inflammation in the brains of patients with PD and other neurodegenerative diseases in which neuroinflammation is prominent. Their results will facilitate the development of much needed disease-modifying therapies.

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Salinomycin kills cancer stem cells by sequestering iron in lysosomes

Nature chemistry, 2017

Cancer stem cells (CSCs) represent a subset of cells within tumours that exhibit self-renewal pro... more Cancer stem cells (CSCs) represent a subset of cells within tumours that exhibit self-renewal properties and the capacity to seed tumours. CSCs are typically refractory to conventional treatments and have been associated to metastasis and relapse. Salinomycin operates as a selective agent against CSCs through mechanisms that remain elusive. Here, we provide evidence that a synthetic derivative of salinomycin, which we named ironomycin (AM5), exhibits a more potent and selective activity against breast CSCs in vitro and in vivo, by accumulating and sequestering iron in lysosomes. In response to the ensuing cytoplasmic depletion of iron, cells triggered the degradation of ferritin in lysosomes, leading to further iron loading in this organelle. Iron-mediated production of reactive oxygen species promoted lysosomal membrane permeabilization, activating a cell death pathway consistent with ferroptosis. These findings reveal the prevalence of iron homeostasis in breast CSCs, pointing tow...

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An approach to suppress the evolution of resistance in BRAF(V600E)-mutant cancer

Nature medicine, 2017

The principles that govern the evolution of tumors exposed to targeted therapy are poorly underst... more The principles that govern the evolution of tumors exposed to targeted therapy are poorly understood. Here we modeled the selection and propagation of an amplification in the BRAF oncogene (BRAF(amp)) in patient-derived tumor xenografts (PDXs) that were treated with a direct inhibitor of the kinase ERK, either alone or in combination with other ERK signaling inhibitors. Single-cell sequencing and multiplex fluorescence in situ hybridization analyses mapped the emergence of extra-chromosomal amplification in parallel evolutionary trajectories that arose in the same tumor shortly after treatment. The evolutionary selection of BRAF(amp) was determined by the fitness threshold, the barrier that subclonal populations need to overcome to regain fitness in the presence of therapy. This differed for inhibitors of ERK signaling, suggesting that sequential monotherapy is ineffective and selects for a progressively higher BRAF copy number. Concurrent targeting of the RAF, MEK and ERK kinases, ...

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An iron hand over cancer stem cells

Autophagy, Jan 14, 2017

The paradigm of cancer stem cells (CSCs) defines the existence of cells exhibiting self-renewal a... more The paradigm of cancer stem cells (CSCs) defines the existence of cells exhibiting self-renewal and tumor-seeding capacity. These cells have been associated with tumor relapse and are typically resistant to conventional chemotherapeutic agents. Over the past decade, chemical biology studies have revealed a significant number of small molecules able to alter the proliferation of these cells in various settings. The natural product salinomycin has emerged as the most promising anti-CSC agent. However, an explicit mechanism of action has not yet been characterized, in particular due to the pleiotropic responses salinomycin is known for. In this punctum, we describe our recent discovery that salinomycin and the more potent synthetic derivative we named ironomycin sequester lysosomal iron. We found that these compounds, by blocking iron translocation, induce an iron-depletion response leading to a lysosomal degradation of ferritin followed by an iron-mediated lysosomal production of reac...

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Event Detection in Molecular Communication Networks With Anomalous Diffusion

IEEE Communications Letters, 2017

A key problem in nanomachine networks is how information from sensors is to be transmitted to a f... more A key problem in nanomachine networks is how information from sensors is to be transmitted to a fusion center. In this paper, we propose a molecular communicationbased event detection network. In particular, we develop a detection framework that can cope with scenarios where the molecules propagate according to anomalous diffusion instead of the conventional Brownian motion. We propose an algorithm for optimizing the network throughput by exploiting tools from reinforcement learning. Our algorithms are evaluated with the aid of numerical simulations, which demonstrate the tradeoffs between performance and complexity.

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Outage probability of full-duplex cognitive relay networks with partial relay selection

2017 International Conference on Recent Advances in Signal Processing, Telecommunications & Computing (SigTelCom), 2017

This paper investigates the outage performance of full duplex cognitive radio networks. We consid... more This paper investigates the outage performance of full duplex cognitive radio networks. We consider that a dual-hop system with multiple decode-and-forward (DF) relays. We assume that there is no direct link between secondary source terminal (S) and destination (D), and self-interference exists at the relays. All the links are independent identically distributed (IID) Rayleigh distributed. In order to analysis the outage performance, the exact closed-form expression of the outage probability is derived. Then we do simulations in different conditions to corroborate our theoretical analyses. Our results show that the system outperforms when the relay (R) is close to D and P is far away S.

Real and virtual wireless radio network emulator

MILCOM 2016 - 2016 IEEE Military Communications Conference, 2016

In this paper, we discuss the use of the RF Wireless Network Environment emulator. Its architectu... more In this paper, we discuss the use of the RF Wireless Network Environment emulator. Its architecture and capabilities are investigated. Four case studies of the RF network emulator are presented in this paper. The first case study simulates the slow-hopping anti-jamming waveform. The second case study is the application of spectrum masking, the third is the use of power difference of arrival localization algorithm to triangulate the location of a local unknown emitter and the fourth utilizes the emulator for testing and verification of a Multiple Link Common Data Link System. The network architecture and setup of the environment emulator for each case is discussed in detail.

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A Synthetic Study towards the Marmycins and Analogues

Synthesis, 2016

A methodological study towards the total synthesis of marmycin A/B is described exploiting a comm... more A methodological study towards the total synthesis of marmycin A/B is described exploiting a commercial anthraquinone molecule as model compound. The challenging synthetic pathway uncovers a copper-catalysed Ullmann cross-coupling to attach the sugar backbone by means of C–N bond formation and, finally, an intramolecular Friedel–Crafts C–C glycosylation to successfully afford the core structure of marmycin A. This methodology has been successfully applied to the genuine anthraquinone moiety leading to the natural product and simpler structural analogues.

Matlab and COTS instrumentations to reduce time and risk factors in design to the stand-alone QAM test system

Proceedings AUTOTESTCON 2003. IEEE Systems Readiness Technology Conference.

In this paper, we discuss how Matlab and standalone COTS instruments can be used to cut down the ... more In this paper, we discuss how Matlab and standalone COTS instruments can be used to cut down the time to study the feasibility of a high speed digital communication test system. The result is a rack-and-stack QAM transceiver with the capability to characterize a device under test (DUT) in terms of bit error rate (BER) and error vector magnitude (EVM).

Synthesis of marmycin A and investigation into its cellular activity

Nature Chemistry, 2015

Anthracyclines such as doxorubicin are used extensively in the treatment of cancers. Anthraquinon... more Anthracyclines such as doxorubicin are used extensively in the treatment of cancers. Anthraquinone-related angucyclines also exhibit antiproliferative properties and have been proposed to operate via similar mechanisms, including direct genome targeting. Here, we report the chemical synthesis of marmycin A and the study of its cellular activity. The aromatic core was constructed by means of a one-pot multistep reaction comprising a regioselective Diels-Alder cycloaddition, and the complex sugar backbone was introduced through a copper-catalysed Ullmann cross-coupling, followed by a challenging Friedel-Crafts cyclization. Remarkably, fluorescence microscopy revealed that marmycin A does not target the nucleus but instead accumulates in lysosomes, thereby promoting cell death independently of genome targeting. Furthermore, a synthetic dimer of marmycin A and the lysosome-targeting agent artesunate exhibited a synergistic activity against the invasive MDA-MB-231 cancer cell line. These findings shed light on the elusive pathways through which anthraquinone derivatives act in cells, pointing towards unanticipated biological and therapeutic applications.

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Virtual Field Test for cognitive-dynamic spectrum access radios and spectrum usage inventory

2014 USNC-URSI Radio Science Meeting (Joint with AP-S Symposium), 2014

Summary form only given. A RF spectrum survey was conducted during a Navy exercise in the summer ... more Summary form only given. A RF spectrum survey was conducted during a Navy exercise in the summer of 2013 to characterize the electromagnetic environment of a military surface ship and the associated emissions of complementary ships present during the exercise. The spectrum survey system consists of receiver antennas, a real-time spectrum analyzer, computer and associated instrumentation. The spectrum range from 20 MHz-6000 MHz and from 9390 MHz-9430 MHz were surveyed and captured in 40 MHz bandwidth blocks. For each 40 MHz block, the I/Q data of the spectrum was saved in the .mat format compatible with MATLAB®; a screenshot of each collected spectrum band was also saved. The I/Q data represents the environment, however, it cannot be used in that format for a spectrum usage inventory. The I/Q data is post-processed to provide a spectrum utilization profile for a particular frequency band. MATLAB® scripts were created to generate a matrix of integer values to represent multiple granularity levels of the absolute power in the spectrum represented by the collected data. The dimensions of the matrix can be scaled to provide a time or frequency resolution and power granularity level supporting the analysis needs. A total of 138 GB of data were collected in three days on board the ship. During the exercise, other research groups performed collections at different shore and shipboard locations. Comparative analysis of the data sets with associated position information tagging provides a basis for understanding of the propagation characteristics in the marine environment. The resulting data sets are shared with the US Department of Defense community through incorporation into the DoD Wireless Networking Library, a resource sponsored by the Assistant Secretary of Defense for Research and Engineering. The collected data set can also be manipulated to create specific testing scenarios. The resulting scenarios have been used to regenerate the spectral environment with an arbitrary waveform generator that is a component of the Virtual Field Test Testbed. Regeneration of the synthesized spectral environment scenarios is used in the research and development of cognitive or dynamic spectrum access radios, as well as legacy radios to understand the performance of the radios under relevant spectral conditions. The collection, processing, regeneration and application of the spectrum environment in the Virtual Field Test Testbed are described.

Testing of policy-based dynamic spectrum access radios

2010 - MILCOM 2010 MILITARY COMMUNICATIONS CONFERENCE, 2010

Policy-driven Dynamic Spectrum Access (DSA) systems are emerging as one of the key technologies t... more Policy-driven Dynamic Spectrum Access (DSA) systems are emerging as one of the key technologies to enable the Department of Defense (DoD) to meet its increasing requirements for access to the electromagnetic spectrum. A key open issue surrounding deployment and continuing development of DSA systems concerns (1) the need to test and evaluate the performance of DSA in avoiding interference to itself and assigned incumbent users and (2) the performance of DSA network in the presence of various types of potential interference. In this paper we describe test framework and concepts to characterize performance of DSA-enabled policy-based radios. Our test framework includes tests to characterize the inherent interference-avoidance characteristics of DSA, such as the time to abandon a channel, as well as tests that address performance implications of a particular DSA policy. The test framework also provides for the ability to inject a relevant electromagnetic environment (EME). The proposed framework is flexible allowing for customization of the relevant test conditions, such as the EME, and facilitates simulation of typical communications events such as network formation and fragmentation.

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QAM Evaluation System Development: Concept Verification and Hardware/Software Development

2005 IEEE Instrumentationand Measurement Technology Conference Proceedings

Page 1. IMTC 2005 Instrumentation and Measurement Technology Conference Ontario, Canada 17-19 M... more

Design of optimized reference signal for Joint Time-Frequency Domain Reflectometry-based wiring diagnostics

2008 IEEE AUTOTESTCON, 2008

Abstract In order to maintain the integrity and safe operation of a power system, a state-of-the-... more

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