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Abstract Image‐based cytometry faces challenges due to technical variations arising from different experimental batches and conditions, such as differences in instrument configurations or image acquisition protocols, impeding genuine biological interpretation of cell morphology. Existing solutions, often necessitating extensive pre‐existing data knowledge or control samples across batches, have proved limited, especially with complex cell image data. To overcome this, “Cyto‐Morphology Adversarial Distillation” (CytoMAD), a self‐supervised multi‐task learning strategy that distills biologically relevant cellular morphological information from batch variations, is introduced to enable integrated analysis across multiple data batches without complex data assumptions or extensive manual annotation. Unique to CytoMAD is its “morphology distillation”, symbiotically paired with deep‐learning image‐contrast translation—offering additional interpretable insights into label‐free cell morphology. The versatile efficacy of CytoMAD is demonstrated in augmenting the power of biophysical imaging cytometry. It allows integrated label‐free classification of human lung cancer cell types and accurately recapitulates their progressive drug responses, even when trained without the drug concentration information. CytoMAD also allows joint analysis of tumor biophysical cellular heterogeneity, linked to epithelial‐mesenchymal plasticity, that standard fluorescence markers overlook. CytoMAD can substantiate the wide adoption of biophysical cytometry for cost‐effective diagnosis and screening.

We report a solid-state traveling-wave amplifier (TWA) realized through monolithic integration of transistors with a SiC substrate-integrated waveguide (SIW). The TWA uses a stepped-impedance microstrip line as the input divider, but a low-loss, high-power-capacity SIW as the output combiner. The input signal is distributed to four GaN high-electron mobility transistors (HEMTs) evenly in magnitude but with 90° successive phase delays at the fundamental frequency. The HEMTs are distributed in the SIW in a period of a half wavelength at the second harmonic frequency, so that their outputs are combined coherently at the SIW output. To overcome the limited speed of the HEMTs, they are driven nonlinearly to generate second harmonics, and their fundamental outputs are suppressed with the SIW acting as a high-pass filter. The measured characteristics of the TWA agree with that simulated at the small-signal level, but exceeds that simulated at the large-signal level. For example, under an input of 15 dBm at 70 GHz, the output at 140 GHz is 38-dB above that at 70 GHz. Under an input around 70 GHz and 20 dBm, the output around 140 GHz is 14 dBm with a 3-dB bandwidth of 6%. This is not only the first D-band frequency multiplier based on the GaN HEMT technology, but also one with the highest output power and the lowest fundamental leakage among all D-band multipliers of different transistor technologies. This proof-of-principle demonstration opens the path to improve the power, gain and efficiency of sub-terahertz TWAs with higher-performance transistors and drive circuits. Although the demonstration is through monolithic integration, the approach is applicable to heterogeneous integration with the SIW and transistors fabricated on separate chips.

Hexagonal semiconductors such as 4H SiC have important high-frequency, high-power, and high-temperature applications. The applications require accurate knowledge of both ordinary and extraordinary relative permittivities, ϵ⊥ and ϵ||, perpendicular and parallel, respectively, to the c axis of these semiconductors. However, due to challenges for suitable test setups and precision high-frequency measurements, little reliable data exists for these semiconductors especially at millimeter-wave frequencies. Recently, we reported ϵ|| of 4H SiC from 110 to 170 GHz. This paper expands on the previous report to include both ϵ⊥ and ϵ|| of the same material from 55 to 330 GHz, as well as their temperature and humidity dependence enabled by improving the measurement precision to two decimal points. For example, at room temperature, real ϵ⊥ and ϵ|| are constant at 9.77 ± 0.01 and 10.20 ± 0.05, respectively. By contrast, the ordinary loss tangent increases linearly with the frequency f in the form of (4.9 ± 0.1) × 10−16 f. The loss tangent, less than 1 × 10−4 over most millimeter-wave frequencies, is significantly lower than that of sapphire, our previous low-loss standard. Finally, both ϵ⊥ and ϵ|| have weak temperature coefficients on the order of 10−4 /°C. The knowledge reported here is especially critical to millimeter-wave applications of 4H SiC, not only for solid-state devices and circuits, but also as windows for high-power vacuum electronics.

Advances and updates in medical applications utilizing microwave techniques and technologies are reviewed in this paper. The article aims to provide an overview of enablers for microwave medical applications and their recent progress. The emphasis focuses on the applications of microwaves, in the following order, for 1) signal and data communication for implants and wearables through the human body, 2) electromagnetic energy transfer through tissues, 3) noninvasive, remote or in situ physical and biochemical sensing, and 4) therapeutic purposes by changing tissue properties with controlled thermal effects. For signal and data communication and wireless power transfer, implant and wearable applications are discussed in the categories of pacemakers, endoscopic capsules, brain interfaces, intraocular, cardiac and intracranial pressure sensors, neurostimulators, endoluminal implants, artificial retina, smart lenses, and cochlear implants. For noninvasive sensing, remote vital sign radar, biological cell probing, magnetic resonance and microwave imaging, biochemical, blood glucose, hydration and biomarker sensing applications are introduced. For therapeutic uses, the developments of microwave ablation, balloon angioplasty, and hyperthermia applications are reviewed. The scopes of this article mainly concentrate on the research and development efforts in the past 20 years. Recent review articles on specific topics are cited with accomplishment highlights and trends deliberated. At the end of this article, a brief history of the IEEE Microwave Theory and Techniques Society (MTT-S) Biological Effects and Medical Applications committee and the contributions by its members to the promotion and advancement of microwave technologies in medical fields are chronicled.

The AlN/GaN/AlN heterostructure is attractive for microwave and millimeter-wave power devices due to its thin top barrier, tight carrier confinement, and improved breakdown voltage. This work explores the large-signal RF performance of high-electron-mobility transistors on this heterostructure. Results are highlighted by record high on-current of 3.6 A/mm, and record maximum oscillation frequency ( $f_{max}$ ) of 233 GHz. The load-pull power sweep at 10 GHz demonstrate a peak power added efficiency (PAE) of 22.7% with an associated gain ( $G_{T}$ ) of 8.7 dB and output power ( $P_{out}$ ) of 3 W/mm. When optimized for power, the peak $P_{out}$ of 3.3 W/mm has an associated PAE of 14.7% and $G_{T}$ of 3.2 dB. This first demonstration is encouraging for the mm-wave power potential of the AlN/GaN/AlN HEMT.

Abstract In limestone caves, environmental processes often cause alterations of human or animal skeletal remains, complicating classical analytical methods. Exemplary, a proximal femoral skeletal fragment, enclosed by a thick layer of speleothemic calcite deposits, was discovered during the exploration of the Bedara cave in Žumberak, Croatia. An examination without removal of the surrounding mineral deposits, possibly leading to damage of the specimen, was, therefore, desirable. We describe and discuss the applied techniques, including clinical computed tomography, virtual cleaning by a specially developed segmentation protocol using an open-source DICOM viewer, and virtual visualisation and dimensioning using computer-aided design software, so that this “hidden” specimen could be non-invasively examined in great detail. We also report on the circumstances and origin of the find, the results of radiocarbon dating, and its anatomical and taxonomic identification, according to which, the bone fragment belonged to a wild boar (Sus scrofa) from the timeframe of the Middle Eneolithic Retz-Gajary culture in the region (4,781 ± 35 years before present). This study provides a reference for future paleontological and anthropological analyses, seeking to unlock the enormous potential of anatomical studies of comparable skeletal remains that are either petrified or enclosed in speleothemic deposits.

The metabolic signaling pathways that drive pathologic tissue inflammation and damage in humans with pulmonary tuberculosis (TB) are not well understood. Using combined methods in plasma high-resolution metabolomics, lipidomics and cytokine profiling from a multicohort study of humans with pulmonary TB disease, we discovered that IL-1β-mediated inflammatory signaling was closely associated with TCA cycle remodeling, characterized by accumulation of the proinflammatory metabolite succinate and decreased concentrations of the anti-inflammatory metabolite itaconate. This inflammatory metabolic response was particularly active in persons with multidrug-resistant (MDR)-TB that received at least 2 months of ineffective treatment and was only reversed after 1 year of appropriate anti-TB chemotherapy. Both succinate and IL-1β were significantly associated with proinflammatory lipid signaling, including increases in the products of phospholipase A2, increased arachidonic acid formation, and metabolism of arachidonic acid to proinflammatory eicosanoids. Together, these results indicate that decreased itaconate and accumulation of succinate and other TCA cycle intermediates is associated with IL-1β-mediated proinflammatory eicosanoid signaling in pulmonary TB disease. These findings support host metabolic remodeling as a key driver of pathologic inflammation in human TB disease.

Using epitaxial aluminum nitride (AlN) developed for ultraviolet photonics and high-speed electronics, we demonstrate suspended AlN thin-film bulk acoustic resonators (FBARs) at 9.2 GHz in the X-band (8–12 GHz) of the microwave spectrum. The resonators show a Q m a x ≈ 614 and a figure of merit f ⋅ Q ≈ 5.6 THz. The material stack of these epi-AlN FBARs allows monolithic integration with AlN/GaN/AlN quantum well high-electron-mobility-transistors to a unique RF front end and also enable integration with epitaxial nitride superconductors for microwave filters for quantum computing. [ABSTRACT FROM AUTHOR]

Background Emerging resistance to bedaquiline (BDQ) threatens to undermine advances in the treatment of drug-resistant tuberculosis (DRTB). Characterizing serial Mycobacterium tuberculosis (Mtb) isolates collected during BDQ-based treatment can provide insights into the etiologies of BDQ resistance in this important group of DRTB patients. Methods We measured mycobacteria growth indicator tube (MGIT)–based BDQ minimum inhibitory concentrations (MICs) of Mtb isolates collected from 195 individuals with no prior BDQ exposure who were receiving BDQ-based treatment for DRTB. We conducted whole-genome sequencing on serial Mtb isolates from all participants who had any isolate with a BDQ MIC >1 collected before or after starting treatment (95 total Mtb isolates from 24 participants). Results Sixteen of 24 participants had BDQ-resistant TB (MGIT MIC ≥4 µg/mL) and 8 had BDQ-intermediate infections (MGIT MIC = 2 µg/mL). Participants with pre-existing resistance outnumbered those with resistance acquired during treatment, and 8 of 24 participants had polyclonal infections. BDQ resistance was observed across multiple Mtb strain types and involved a diverse catalog of mmpR5 (Rv0678) mutations, but no mutations in atpE or pepQ. Nine pairs of participants shared genetically similar isolates separated by <5 single nucleotide polymorphisms, concerning for potential transmitted BDQ resistance. Conclusions BDQ-resistant TB can arise via multiple, overlapping processes, including transmission of strains with pre-existing resistance. Capturing the within-host diversity of these infections could potentially improve clinical diagnosis, population-level surveillance, and molecular diagnostic test development. [ABSTRACT FROM AUTHOR]