Synthetic Array Research Articles

Imaging upper mantle anisotropy with teleseismicP-wave delays: insights from tomographic reconstructions of subduction simulations

SUMMARYDespite the well-established anisotropic nature of Earth’s upper mantle, the influence of elastic anisotropy on teleseismic P-wave imaging remains largely ignored. Unmodelled anisotropic heterogeneity can lead to substantial isotropic velocity artefacts that may be misinterpreted as compositional heterogeneities. Recent studies have demonstrated the possibility of inverting P-wave delay times for the strength and orientation of seismic anisotropy. However, the ability of P-wave delay times to constrain complex anisotropic patterns, such as those expected in subduction settings, remains unclear as synthetic testing has been restricted to the recovery of simplified block-like structures using ideal self-consistent data (i.e. data produced using the assumptions built into the tomography algorithm). Here, we present a modified parametrization for imaging arbitrarily oriented hexagonal anisotropy and test the method by reconstructing geodynamic simulations of subduction. Our inversion approach allows for isotropic starting models and includes approximate analytic finite-frequency sensitivity kernels for the simplified anisotropic parameters. Synthetic seismic data are created by propagating teleseismic waves through an elastically anisotropic subduction zone model created via petrologic-thermomechanical modelling. Delay times across a synthetic seismic array are measured using conventional cross-correlation techniques. We find that our imaging algorithm is capable of resolving large-scale features in subduction zone anisotropic structure (e.g. toroidal flow pattern and dipping fabrics associated with the descending slab). Allowing for arbitrarily oriented anisotropy also results in a more accurate reconstruction of isotropic slab structure. In comparison, models created assuming isotropy or only azimuthal anisotropy contain significant isotropic and anisotropic imaging artefacts that may lead to spurious interpretations. We conclude that teleseismic P-wave traveltimes are a useful observable for probing the 3-D distribution of upper mantle anisotropy and that anisotropic inversions should be explored to better understand the nature of isotropic velocity anomalies particularly in subduction settings.

3D Synthetic Microstructures Fabricated by Two‐Photon Polymerization Promote Homogeneous Expression of NANOG and ESRRB in Mouse Embryonic Stem Cells

AbstractThe development of in vitro models, which accurately recapitulate early embryonic development, is one of the fundamental challenges in stem cell research. Most of the currently employed approaches involve the culture of embryonic stem cells (ESCs) on 2D surfaces. However, the monolayer nature of these cultures does not permit cells to grow and proliferate in realistic 3D microenvironments, as in an early embryo. In this paper, novel 3D synthetic microstructure arrays, fabricated by two‐photon polymerization photolithography, are utilized to mimic tissue‐specific architecture, enabling cell‐to‐matrix interaction and cell‐to‐cell communication in vitro. Mouse ESCs (mESCs) are able to grow and proliferate on these structures and maintain their pluripotent state. Furthermore, the 3D microstructure arrays are integrated into a microscopy slide allowing the evaluation of the expression of key pluripotency factors at the single cell level. Comparing 2D and 3D surfaces, mESCs grown in serum + leukemia inhibitory factor on 3D microstructures exhibit a stronger signal intensity of three pluripotency markers—homeobox protein NANOG, octamer‐binding transcription factor 4, and estrogen‐related receptor beta (ESRRB)—and more homogenous expression of NANOG and ESRRB, than cells cultivated in 2i medium, demonstrating that 3D microstructures capture naïve pluripotency in vitro. Thus, the slide affords a novel and unique tool to model and study early development.

τ-SGA: synthetic genetic array analysis for systematically screening and quantifying trigenic interactions in yeast.

Systematic complex genetic interaction studies have provided insight into high-order functional redundancies and genetic network wiring of the cell. Here, we describe a method for screening and quantifying trigenic interactions from ordered arrays of yeast strains grown on agar plates as individual colonies. The protocol instructs users on the trigenic synthetic genetic array analysis technique, τ-SGA, for high-throughput screens. The steps describe construction of the double-mutant query strains and the corresponding single-mutant control query strains, which are screened in parallel in two replicates. The screening experimental set-up consists of sequential replica-pinning steps that enable automated mating, meiotic recombination and successive haploid selection steps for the generation of triple mutants, which are scored for colony size as a proxy for fitness, which enables the calculation of trigenic interactions. The procedure described here was used to conduct 422 trigenic interaction screens, which generated ~460,000 yeast triple mutants for trigenic interaction analysis. Users should be familiar with robotic equipment required for high-throughput genetic interaction screens and be proficient at the command line to execute the scoring pipeline. Large-scale screen computational analysis is achieved by using MATLAB pipelines that score raw colony size data to produce τ-SGA interaction scores. Additional recommendations are included for optimizing experimental design and analysis of smaller-scale trigenic interaction screens by using a web-based analysis system, SGAtools. This protocol provides a resource for those who would like to gain a deeper, more practical understanding of trigenic interaction screening and quantification methodology.

Dilated Arrays: A Family of Sparse Arrays With Increased Uniform Degrees of Freedom and Reduced Mutual Coupling on a Moving Platform

Recently, dilated nested arrays have been proposed on a moving platform to increase the uniform degrees of freedom (uDOF) by a factor of three by exploiting array motion. However, no literature addresses the issue whether the same dilation method still performs well for other array geometries such as coprime arrays, augmented nested arrays and minimum redundancy arrays. Compared with nested arrays, these arrays either achieve higher uDOF or exhibit more robustness to mutual coupling among sensors. In this paper, we propose a novel sparse array geometry named dilated arrays (DAs) on a moving platform by applying the dilation method to other array geometries. First, by exploiting the relationship between the element positions in the difference coarrays of the original linear array and the synthetic array after motion, we prove that, for a DA on a moving platform, the maximum uDOF can be tripled compared to that of its original array regardless of the array geometry. Therefore, the number of sources that can be resolved for direction-of-arrival (DOA) estimation is increased threefold. Second, we prove that a DA reduces mutual coupling compared with its original array. As a result, the DA is more robust to mutual coupling than its original array. Third, we extend one-dimensional DAs to the two-dimensional (2-D) case, yielding a new 2-D sparse array geometry named two-parallel DAs. We show that by exploiting array motion, two-parallel DAs can increase the number of detectable sources threefold. Numerical simulations demonstrate the superior performance of the proposed array geometries.

A Novel Nested Array for Real-Valued Sources Exploiting Array Motion

In this letter, a novel nested array is proposed which not only increases the degrees of freedom (DOF) but also reduces the mutual coupling that occurs in the general nested array structure by moving the original array only half wavelength. Here we deal with real-valued sources like AM or BPSK whereby we can explore the property of the sum coarray along with the difference coarray of the synthetic array (SA). It is assumed that the sensing environment does not change over the array motion of half wavelength. First, we develop the novel nested array and prove that the sum difference coarray (SDCA) of SA is hole-free up to a certain number. Then we provide closed-form expressions for the number of unique and consecutive lags of the SDCA of SA. We also optimize the array for a given number of sensors. Simulation results show the superiority of the proposed array over other existing arrays.

Mapping Synthetic Dosage Lethal Genetic Interactions in Saccharomyces cerevisiae.

Synthetic dosage lethality (SDL) is a type of genetic interaction that occurs when increasing the expression of a gene causes a fitness defect, such as lethality, in a specific mutant background but has little effect on fitness in a wild-type background. SDL genetic interactions discovered in model organisms such as the budding yeast, Saccharomyces cerevisiae , represent candidate genetic interactions that may be conserved in human cells. In some cases, SDL genetic interactions can be applied to study the biological implications of genes overexpressed in cancer and to discover potential anticancer therapeutic drug targets. Here, we provide a protocol for screening a query overexpression gene against ordered arrays of yeast mutant strains to identify mutations that sensitize yeast to increased dosage of a specific gene product. We outline applications and procedures for screening with an inducibly overexpressed wild-type gene, a common feature of cancer cells, or with an inducibly overexpressed gene carrying a dominant-negative missense mutation as a model of protein-inhibitor interactions. This high-throughput screening platform is adapted from synthetic genetic array (SGA) technology and enables the generation of large-scale SDL genetic interaction networks that can be applied to study gene/pathway function and to identify cross-species cancer-relevant processes.

Quantitative Genetic Screens for Mapping Bacterial Pathways and Functional Networks.

Escherichia coli synthetic genetic array (eSGA) screening procedure enables high-throughput systematic mapping of pairwise genetic interactions in E. coli. The eSGA method exploits E. coli's rapid growth, its ease of genetic manipulation, and efficient genetic exchange via conjugation. Replica pinning is used to grow and mate arrayed sets of single gene mutant strains as well as to select double mutants en masse. Strain fitness, which is the eSGA readout, is determined by the digital imaging of the plates and subsequent colony size measurements. Comparing single and double mutant colony sizes then allows for identifying interacting genes. Using eSGA on a global or a smaller process-centric scale can help reveal gene functions and reconstruct genetic interaction networks with known and novel connections between genes and pathways.

Trigenic Synthetic Genetic Array (τ-SGA) Technique for Complex Interaction Analysis.

Complex genetic interactions occur when mutant alleles of multiple genes combine to elicit an unexpected phenotype, which could not be predicted given the expectation based on the combination of phenotypes associated with individual mutant alleles. Trigenic Synthetic Genetic Array (τ-SGA) methodology was developed for the systematic analysis of complex interactions involving combinations of three gene perturbations. With a series of replica pinning steps of the τ-SGA procedure, haploid triple mutants are constructed through automated mating and meiotic recombination. For example, a double-mutant query strain carrying two mutant alleles of interest, such as a deletion allele of a nonessential gene and a conditional temperature-sensitive allele of an essential gene, is crossed to an input array of yeast mutants, such as the diagnostic array set of ~1200 mutants, to generate an output array of triple mutants. The colony-size measurements of the resulting triple mutants are used to estimate cellular fitness and quantify trigenic interactions by incorporating corresponding single- and double-mutant fitness estimates. Trigenic interaction networks can be further analyzed for functional modules using various clustering and enrichment analysis tools. Complex genetic interactions are rich in functional information and provide insight into the genotype-to-phenotype relationship, genome size, and speciation.

Underdetermined Direction-of-Arrival Estimation Using Sparse Circular Arrays on a Rotating Platform

In this letter, we propose to exploit the array motion of sparse circular arrays (SCA) on a rotating platform to increase the degrees of freedom (DOF) (i.e. the number of unique spatial lags) associated with the rotating array when compared to the array on a fixed platform. This increases the total number of sources that can be resolved by the rotating SCA with the same amount of physical sensors. The signal model for the combined synthetic array before and after a unit rotation motion is derived together with the closed-form expression for the increase in the DOF of a rotating nested sparse circular array (NSCA). A new modified NSCA is proposed and it is shown that the DOF of the proposed sparse array is higher than the conventional NSCA under motion with the same number of sensors. A simulation study is carried out to estimate the direction of arrival (DOA) of signals in a sensing environment that is assumed to be stationary over array motion of unit rotation and it verifies the effectiveness of array motion to increase the DOF of an SCA. The simulations also show the improved performance of the proposed NSCA.

2D DOA Estimation Exploiting Vertical Synthetic Planar Arrays

In this paper, vertical motions of sparse linear arrays (SLAs) are utilized to generate equivalent synthetic planar arrays for two-dimensional (2D) direction-of-arrival (DOA) estimation. The proposed array geometry named vertical synthetic planar array (VSPA) consists of an arbitrary SLA on the x-axis and a series of its time-shifted arrays in the vertical orientation. With the original linear array and the moving trail known, the difference coarray of VSPA can be easily obtained. By utilizing both the synthetic aperture processing and the coarray technique, VSPA has the ability to construct a synthetic planar array with only an SLA used. Compared with the traditional sparse planar arrays (SPAs), such as 2D nested array and 2D coprime array, VSPA can achieve higher degree-of-freedom and improved 2D DOA estimation performance with the same number of sensors. Moreover, as different original linear arrays and moving trails can be chosen for different applications, the construction of VSPA is of high flexibility. Numerical simulations are presented to verify the superiority of the proposed VSPA geometry over other typical SPAs.

Comprehensive Synthetic Genetic Array Analysis of Alleles That Interact with Mutation of the Saccharomyces cerevisiae RecQ Helicases Hrq1 and Sgs1.

Most eukaryotic genomes encode multiple RecQ family helicases, including five such enzymes in humans. For many years, the yeast Saccharomyces cerevisiae was considered unusual in that it only contained a single RecQ helicase, named Sgs1. However, it has recently been discovered that a second RecQ helicase, called Hrq1, resides in yeast. Both Hrq1 and Sgs1 are involved in genome integrity, functioning in processes such as DNA inter-strand crosslink repair, double-strand break repair, and telomere maintenance. However, it is unknown if these enzymes interact at a genetic, physical, or functional level as demonstrated for their human homologs. Thus, we performed synthetic genetic array (SGA) analyses of hrq1Δ and sgs1Δ mutants. As inactive alleles of helicases can demonstrate dominant phenotypes, we also performed SGA analyses on the hrq1-K318A and sgs1-K706A ATPase/helicase-null mutants, as well as all combinations of deletion and inactive double mutants. We crossed these eight query strains (hrq1Δ, sgs1Δ, hrq1-K318A, sgs1-K706A, hrq1Δ sgs1Δ, hrq1Δ sgs1-K706A, hrq1-K318A sgs1Δ, and hrq1-K318A sgs1-K706A) to the S. cerevisiae single gene deletion and temperature-sensitive allele collections to generate double and triple mutants and scored them for synthetic positive and negative genetic effects based on colony growth. These screens identified hundreds of synthetic interactions, supporting the known roles of Hrq1 and Sgs1 in DNA repair, as well as suggesting novel connections to rRNA processing, mitochondrial DNA maintenance, transcription, and lagging strand synthesis during DNA replication.

The Genetic and Physical Interactomes of the Saccharomyces cerevisiae Hrq1 Helicase.

The human genome encodes five RecQ helicases (RECQL1, BLM, WRN, RECQL4, and RECQL5) that participate in various processes underpinning genomic stability. Of these enzymes, the disease-associated RECQL4 is comparatively understudied due to a variety of technical challenges. However, Saccharomyces cerevisiae encodes a functional homolog of RECQL4 called Hrq1, which is more amenable to experimentation and has recently been shown to be involved in DNA inter-strand crosslink (ICL) repair and telomere maintenance. To expand our understanding of Hrq1 and the RecQ4 subfamily of helicases in general, we took a multi-omics approach to define the Hrq1 interactome in yeast. Using synthetic genetic array analysis, we found that mutations of genes involved in processes such as DNA repair, chromosome segregation, and transcription synthetically interact with deletion of HRQ1 and the catalytically inactive hrq1-K318A allele. Pull-down of tagged Hrq1 and mass spectrometry identification of interacting partners similarly underscored links to these processes and others. Focusing on transcription, we found that hrq1 mutant cells are sensitive to caffeine and that mutation of HRQ1 alters the expression levels of hundreds of genes. In the case of hrq1-K318A, several of the most highly upregulated genes encode proteins of unknown function whose expression levels are also increased by DNA ICL damage. Together, our results suggest a heretofore unrecognized role for Hrq1 in transcription, as well as novel members of the Hrq1 ICL repair pathway. These data expand our understanding of RecQ4 subfamily helicase biology and help to explain why mutations in human RECQL4 cause diseases of genomic instability.

Structured sparse array design exploiting two uniform subarrays for DOA estimation on moving platform

Array motion can efficiently enhance the achievable number of degrees-of-freedom (DOFs) by the virtue of filling the neighboring holes of each lag in the difference co-array of a linear sparse array. In this paper, a new structured sparse array design exploiting two uniform subarrays on a moving platform is proposed for direction-of arrival (DOA) estimation problems. The proposed array design yields a fully filled co-array. It compresses sensor spacing of one subarray to three times the unit sensor spacing while dilating that of the other subarray. The numbers of sensors in the two subarrays are chosen as arbitrary integers without the limitation of coprimality. The conditions on the array parameters to achieve full augmentability under array motion are provided. Closed-form expressions of maximum DOFs in the difference co-array of the synthetic array, which comprises the sensor positions before and after motion, are delineated. The non-coprimality of the sensor numbers is analyzed when the two subarrays are aligned at the reference sensor, and shown to offer higher DOFs than the coprimality. Numerical results of DOA estimation using the proposed array design are provided for performance comparison and validations of analysis.

Characteristics of array of distributed synthetic jets and effect on turbulent boundary layer

An array of distributed round synthetic jets was used to control a fully developed turbulent boundary layer. The study focused on the related skin friction drag reduction and mechanisms involved. The control effects were analyzed by measuring the streamwise velocities using a hot-wire anemometer downstream of the array. A reduction in the skin friction was observed both in the regions downstream of the orifices and in the regions between two adjacent orifices. A statistical analysis with the variable-interval time-averaging (VITA) technique demonstrated a weakened bursting intensity with synthetic jet in the near-wall region. The streamwise vortices were lifted by the upwash effect caused by synthetic jet and induced less low-speed streaks. The control mechanism acted in a way to suppress the dynamic interaction between the streamwise vortices and low-speed streaks and to attenuate the turbulence production in the near-wall region. The forcing frequency was found to be a more relevant parameter when synthetic jet was applied in turbulent boundary layer flow control. A higher forcing frequency induced a higher reduction in the skin friction. The power spectral density and autocorrelation of the fluctuating velocities showed that the synthetic jets gradually decayed in the streamwise direction, having an effect as far as 34.5 times the displacement thickness that was on the trailing edge of the distributed synthetic jets array.

Functional Characterization of a Novel Oxidative Stress Protection Protein in the Pathogenic Yeast Candida glabrata.

Candida species are important pathogens of humans and the fourth most commonly isolated pathogen from nosocomial blood stream infections. Although Candida albicans is the principle causative agent of invasive candidosis, the incidence of Candida glabrata infections has rapidly grown. The reason for this increase is not fully understood, but it is clear that the species has a higher innate tolerance to commonly administered azole antifungals, in addition to being highly tolerant to stresses especially oxidative stress. Taking the approach that using the model organism, Saccharomyces cerevisiae, with its intrinsic sensitivity to oxidative stress, we hypothesized that by expressing mediators of stress resistance from C. glabrata in S. cerevisiae, it would result in induced resistance. To test this we transformed, en-masse, the C. glabrata ORFeome library into S. cerevisiae. This resulted in 1,500 stress resistant colonies and the recovered plasmids of 118 ORFs. Sequencing of these plasmids revealed a total of 16 different C. glabrata ORFs. The recovery of genes encoding known stress protectant proteins such as GPD1, GPD2 and TRX3 was predicted and validated the integrity of the screen. Through this screen we identified a C. glabrata unique ORF that confers oxidative stress resistance. We set to characterise this gene herein, examining expression in oxidative stress sensitive strains, comet assays to measure DNA damage and synthetic genetic array analysis to identify genetic interaction maps in the presence and absence of oxidative stress.

Influence of Antenna Pattern on Synthetic Aperture Radar Resolution for NDE Applications

The effect of antenna gain pattern on synthetic aperture radar (SAR) imaging is analyzed in this article. In prior investigations, only the effect of antenna half-power beamwidth (HPBW) on the resultant image spatial resolutions were described using approximations that are valid only at very large distances or at small distances with relatively wide HPBW. This article illustrates that this approximation is not valid in the near-field of the synthetic array when the antenna used is highly directive. In this article, the effect of the entire antenna (gain) pattern, instead of just assuming a constant pattern within the HPBW, on SAR image spatial resolutions (both range and cross-range) is demonstrated. Additionally, the effect of approximations which are necessary for implementing fast Fourier transform (FFT)-based algorithms (e.g., $\omega $ - $k$ SAR algorithm) on the image resolutions are also studied. The concept of effective synthetic aperture length is introduced and corresponding empirical formulas are derived. Subsequently, this effective aperture length is used to calculate the image spatial resolutions. Finally, representative measurements were performed to verify the simulation results.

57–64 GHz Imaging/Detection Sensor—Part II: Experiments on Concealed Weapons and Threatening Materials Detection

In this paper, experimental evaluations over the frequency range of a 57–64 GHz for an improved millimeter wave (MMW) imaging/detection system have been conducted. The main objective behind this work is to examine the performance of a high gain and low profile multi sine corrugated AFTSA antenna sensor in the detection of metallic, non-metallic weapons and suspected liquids hidden by clothing, plywood, and plastics. A microwave holography technique based on time domain reflectometry (TDR), which utilizes amplitude information recorded over a 2D aperture, reconstructs a focused image of the target. 60 GHz ISM band imaging detection experiments elaborate the ability for the detection of concealed weapons or other threatening items placed on a body phantom, easily penetrating clothing material of different thicknesses, as well as able to detect through plywood and plastics. The MMW image is detected using a 2D linear scanning platform which generates XY movement, with a $30\times30$ cm2 mechanical range for the object field of view and oriented perpendicular with respect to a lens focal plane. This work is performed with a cross range resolution of $\delta {x}=\delta {y}= 3$ mm achieving a $100\times100$ pixels MMW image. The mechanical setup scanning method is similar to synthetic aperture array with a single AFTSA antenna element measurement, ideal for investigating the probe for 60 GHz band imaging and in detecting concealed threatening items at security surveillance checkpoints.

A synthetic macroscopic magnetic unipole

We demonstrate experimentally with a prototype for the first time, that an artificial emergent magnetic unipole hedgehog field in a simply connected three-dimensional domain is possible, emulating effectively the Dirac model by simply using a novel permanent magnets’ topology and geometrical arrangement in a ring array. Although similar effects were demonstrated by others over the last decade, with these effects usually observed and lasting for a small fraction in time and applied at the quantum or microscopic scale using primary BECs, Skyrmions, Spin Ice and recently Chiral Magnets this was never shown until now and performed at the macro scale and by using normal magnets. The synthetic magnetic unipole ring array prototype progressively twists and steers the magnetic flux into vanishing curl field (i.e. vortex) geometry towards the centre of the ring and its air cap. This mere act alone proves enough to create the desired effect and an apparent isolated magnetic unipole region is observed at the centre of this magnetic ring array, as we have mapped with a 3-axis magnetometer and show with the quantum magnetic-optic device flux viewer, the ferrolens. This apparent unipolar magnetic array exhibits anomalous behavior at its centre, air cap and registers with a magnetometer or a normal compass needle as having the same magnetic polarity on both opposite faces of the ring on the same axis passing through the centre of the ring. Also the other opposite polarity pole is dispersed and confined along the periphery of the ring array with a 90° angle to the unipole axis and none existing in the far field and nowhere to be found. Even in the near field, counting the total number of discrete poles of the magnets of the array including its emergent unipole at the centre, counts to an odd number. The results were analyzed and software simulated and some interesting conclusions are drawn about the ultimate quantum vortex nature of ferromagnetism.

The deubiquitinase USP7 uses a distinct ubiquitin-like domain to deubiquitinate NF-ĸB subunits

The transcription factor NF-ĸB is a master regulator of the innate immune response and plays a central role in inflammatory diseases by mediating the expression of pro-inflammatory cytokines. Ubiquitination-triggered proteasomal degradation of DNA-bound NF-ĸB strongly limits the expression of its target genes. Conversely, USP7 (deubiquitinase ubiquitin-specific peptidase 7) opposes the activities of E3 ligases, stabilizes DNA-bound NF-ĸB, and thereby promotes NF-ĸB–mediated transcription. Using gene expression and synthetic peptide arrays on membrane support and overlay analyses, we found here that inhibiting USP7 increases NF-ĸB ubiquitination and degradation, prevents Toll-like receptor–induced pro-inflammatory cytokine expression, and represents an effective strategy for controlling inflammation. However, the broad regulatory roles of USP7 in cell death pathways, chromatin, and DNA damage responses limit the use of catalytic inhibitors of USP7 as anti-inflammatory agents. To this end, we identified an NF-ĸB–binding site in USP7, ubiquitin-like domain 2, that selectively mediates interactions of USP7 with NF-ĸB subunits but is dispensable for interactions with other proteins. Moreover, we found that the amino acids 757LDEL760 in USP7 critically contribute to the interaction with the p65 subunit of NF-ĸB. Our findings support the notion that USP7 activity could be potentially targeted in a substrate-selective manner through the development of noncatalytic inhibitors of this deubiquitinase to abrogate NF-ĸB activity.

Combining Millimeter-Wave Imaging, Ultrasound and Elastography in a New Multimodal Approach for Breast Cancer Detection: Initial Experimental Results.

In this paper, for the first time, a triple-mode scan using electromagnetic waves, in the shape of millimeter waves, and ultrasound waves, to obtain B-mode and quasistatic elastography images of a phantom of human breast tissues is shown. A homogeneous phantom composed of nontoxic, low-cost and easy-to-handle materials (i.e. water, oil, gelatin and dishwashing liquid) was produced, with an inclusion made of water and agar. These are intended to mimic, in terms of dielectric properties, healthy adipose tissues and neoplastic tissues, respectively. A millimeter-wave imaging prototype was used to scan the phantom, by implementing a linear synthetic array of 24 antennas with a central working frequency of 30 GHz. The phantom was then scanned using an ultrasound research system and a linear-array probe at 7 MHz, acquiring both B-mode and quasi-static elastography images. The millimeter-wave system showed an excellent ability to detect the target placed at about 1.4 cm depth. Also in the ultrasound case the inclusion was correctly detected as a hypoechoic, stiff mass. This first experimental findings show that millimeter-wave, ultrasound and elasticity imaging can be used jointly to detect tumor-like targets into phantoms mimicking healthy breast tissues. Thus, they provide promising preliminary results to further study the application of this multimodal approach in all those critical cases in which such complementary imaging techniques could be exploited for an enhanced tumor detection, based on tissues dielectric, acoustic and elastic properties.