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Flexible capacitive sensors have attracted the attention of researchers owing to their simple structure, ease of realization, and wearability. Currently, flexible capacitive sensors mainly have three-dimensional and two-dimensional structures, which are subject to several limitations in their applications. A low-cost, high-efficiency, and continuously processable process was used to wrap nylon DTY (PA) filaments on the surface of silver-coated nylon (SCN) core yarns and impregnate them with waterborne polyurethane (WPU) to obtain SCN/PA/WPU composite yarns, which were then utilized in the design of SCN/PA/WPU for the preparation of one-dimensionally structured flexible capacitive sensors. The morphology and mechanical properties of the SCN core yarn, SCN/PA wrapped yarn, and SCN/PA/WPU composite yarn were characterized. The strain-sensing performance of the sensor was analyzed, and the sensor was used to monitor human physiological activities. The sensor exhibited excellent strain capacitance sensing performance with a strain range of up to 140%. With a gauge factor of 0.66 at 10% tensile strain, it can detect strains as low as 1% and has good repeatability, withstanding more than 3200 tensile-unload cycles at 80% strain. The one-dimensional structure sensor can be used to monitor the large-scale movements of joints and muscles in various parts of the human body and the physiological signals of tiny human movements, such as breathing, coughing, and facial expressions, which have potential applications in the fields of sports monitoring and smart wearable.

Voltage-controlled oscillators, serving as fundamental components in semiconductor chips, find extensive applications in diverse modules such as phase-locked loops, clock generators, and frequency synthesizers within high-frequency integrated circuits. This study marks the first implementation of superconducting Josephson probe microscopy for near-field microwave detection on multiple voltage-controlled oscillators. Focusing on spectrum tracking, various phenomena, such as stray spectra and frequency drifts, were found under nonsteady operating states. Parasitic electromagnetic fields, originating from power supply lines and frequency divider circuits, were identified as sources of interference between units. The investigation further determined optimal working states by analyzing features of the microwave distributions. Our research not only provides insights into the optimization of circuit design and performance enhancement in oscillators but also emphasizes the significance of nondestructive near-field microwave microscopy as a pivotal tool in characterizing integrated millimeter-wave chips.

BackgroundAlthough trigeminal nerve involvement is a characteristic of multiple sclerosis (MS), its prevalence across studies varies greatly due to MRI resolution and cohort selection bias. The mechanism behind the site specificity of trigeminal nerve injury is still unclear. We aim to determine the prevalence of trigeminal nerve involvement in patients with MS in a consecutive 7T brain MRI cohort.MethodsThis observational cohort originates from an ongoing China National Registry of Neuro-Inflammatory Diseases. Inclusion criteria were the following: age 18 years or older, diagnosis of MS according to the 2017 McDonald criteria and no clinical relapse within the preceding 3 months. Each participant underwent 7T MAGNETOM Terra scanner (Siemens, Erlangen, Germany), using a 32-channel phased array coil at Beijing Tiantan Hospital. T1-weighted magnetisation-prepared rapid acquisition gradient echoes, fluid-attenuated inversion recovery (FLAIR) and fluid and white matter suppression images were used to identify lesions. FLAIR* and T2* weighted images were used to identify central vein sign (CVS) within the trigeminal lesions.Results120 patients underwent 7T MRI scans between December 2021 and May 2023. 19/120 (15.8%) patients had a total of 45 trigeminal lesions, of which 11/19 (57.9%) were bilateral. The linear lesions extended along the trigeminal nerve, from the root entry zone (REZ) (57.8%, 26/45) to the pontine-medullary nucleus (42.2%, 19/45). 26.9% (7/26) of the lesions in REZ showed a typical central venous sign.ConclusionIn this 7T MRI cohort, the prevalence of trigeminal nerve involvement was 15.8%. Characteristic CVS was detected in 26.9% of lesions in REZ. This suggests an inflammatory demyelination mechanism of trigeminal nerve involvement in MS.

Ferrotoroidicity—the fourth form of primary ferroic order—breaks both space and time-inversion symmetry. So far, direct observation of ferrotoroidicity in natural materials remains elusive, which impedes the exploration of ferrotoroidic phase transitions. Here we overcome the limitations of natural materials using an artificial nanomagnet system that can be characterized at the constituent level and at different effective temperatures. We design a nanomagnet array as to realize a direct-kagome spin ice. This artificial spin ice exhibits robust toroidal moments and a quasi-degenerate ground state with two distinct low-temperature toroidal phases: ferrotoroidicity and paratoroidicity. Using magnetic force microscopy and Monte Carlo simulation, we demonstrate a phase transition between ferrotoroidicity and paratoroidicity, along with a cross-over to a non-toroidal paramagnetic phase. Our quasi-degenerate artificial spin ice in a direct-kagome structure provides a model system for the investigation of magnetic states and phase transitions that are inaccessible in natural materials.

•CSF IL-6 levels are higher in CIS patients who converted to NMOSD during follow-up.•High CSF IL-6 levels are a predictor of conversion to NMOSD for CIS patients.•High CSF IL-6 levels are associated with a shorter time to conversion to NMOSD.•The CSF IL-6 levels in CIS patients correlated with the CSF WBC count, protein level, IgG index and clinical severity.

Advanced microwave technologies constitute the foundation of a wide range of modern sciences, including microwave integrated circuits, quantum computing, microwave photonics, spintronics, etc. To facilitate the design of chip-based microwave devices, there is an increasing demand for state-of-the-art microscopic techniques that are capable of characterizing near-field microwave distribution and performance. In this work, we integrate Josephson junctions onto a nanosized quartz tip, forming a highly sensitive microwave mixer on-tip. This allows us to conduct spectroscopic imaging of near-field microwave distributions with high spatial resolution. By leveraging its microwave-sensitive characteristics, our Josephson microscopy achieves a broad detecting bandwidth of ≤200 GHz, as well as remarkable frequency and intensity resolutions. Near-field characterizations of microwave circuits are also conducted to demonstrate the capabilities of Josephson microscopy. Our work emphasizes the benefits of utilizing Josephson microscopy as a real-time, non-destructive technique to advance integrated microwave devices.Josephson microwave microscopy integrating Josephson junctions onto a nanoprobe enables spectroscopic imaging of near-field microwave with a broad bandwidth, presenting a non-destructive technique to characterize microwave devices.

We propose a scientific machine learning (SciML) algorithm toward 3-D dynamic digital twins, which represent multiphysics coupling effects in large-scale electronic chips. The SciML is a burgeoning topic, and here we refer to an organic fusion of scientific computing, model order reduction, and machine learning (ML) method. The proposed model order reduction compresses multiphysics information by a data-driven non-intrusive technique, thus getting rid of the access to backend source code; the proposed ML intrinsically infers the partial differential equation operators encoding the physical process. Numerical experiments showcase that the proposed digital twins have superior properties in real-time intelligent computing and generalization capability in predictive modeling. Nevertheless, it should be mentioned that the presented work is still in an early stage of intelligent digital twins.

In this study, the interaction patterns between whey protein and lactose were investigated after different ratios of whey protein and lactose (1:2.5; 1:3.0; 1:3.5; 1:4.0; 1:4.5) were treated with two typical sterilization process parameters in powdered products (68 °C, 20 min; 72 °C, 15 min) and two typical sterilization process parameters in liquid products (121 °C, 10 min and 121 °C, 15 min). It was found that the degree of the Maillard reaction of whey protein-lactose solution increased with increasing lactose content, increasing sterilization temperature, or extending sterilization time, which was accompanied by changes in the protein structure of whey protein. In addition, glycosylation accelerates the decrease in free sulfhydryl content, decreasing surface hydrophobicity and decreasing fluorescence intensity. These findings highlight the advantages of designing protein-carbohydrate formulations with a high ratio of whey protein-lactose (1:2.5) to meet the requirements of the product standards for preterm/low-birth-weight infant formulas. When comparing only the sterilization processes of powder and liquid products, the pasteurization process of powder products significantly reduced the degree of the Maillard reaction caused by heat treatment and reduced protein denaturation.

The ultrafast modulation of terahertz (THz) waves is essential for numerous applications, such as high-rate wireless communication, nonreciprocal transmission, and linear frequency conversion. However, high-speed THz devices are rare due to the lack of materials that rapidly respond to external stimuli. Here, we demonstrate a dynamic THz metasurface by introducing an ultrathin superconducting microbridge into metallic resonators to form a superconductor-metal hybrid structure. Exploiting the susceptibility of superconducting films to external optical and THz pumps, we realized resonance mode switching within a few picoseconds. The maximum on/off ratio achieved is 11 dB. The observed periodic oscillation of transmission spectra both in the time and frequency domain under intense THz pump pulse excitation reveals the excitation of Higgs amplitude mode, which is used to realize picosecond scale THz modulation. This study opens the door to ultrafast manipulation of THz waves using collective modes of condensates, and highlights an avenue for developing agile THz modulation devices.

Horizontal gene transfer (HGT) plays an important role in evolutionary processes as organisms adapt to their environments, and now cases of gene duplication after HGT in eukaryotes are emerging at an increasing rate. However, the fate and roles of the duplicated genes over time in eukaryotes remain unclear. Here we conducted a comprehensive analysis of the evolution of cysteine synthase (CYS) in lepidopteran insects. Our results indicate that HGT-derived CYSgenes are widespread and have undergone duplication following horizontal transfer in many lepidopteran insects. Moreover, lepidopteran CYS proteins not only have β-cyanoalanine synthase activity but also possess cysteine synthase activity that is involved in sulfur amino acid biosynthesis. Duplicated CYSgenes show marked divergence in gene expression patterns and enzymatic properties, suggesting that they probably have undergone subfunctionalization and/or neofunctionalization in Lepidoptera. The gene transfer of CYSgenes and subsequent duplication appears to have facilitated the adaptation of lepidopteran insects to different diets and promoted their ecological diversification. Overall, this study provides valuable insights into the ecological and evolutionary contributions of CYSin lepidopteran insects.

The ability to control the potential landscape in a medium of interacting particles could lead to intriguing collective behavior and innovative functionalities. Here, we utilize spatially reconfigurable magnetic potentials of a pinwheel artificial-spin-ice (ASI) structure to tailor the motion of superconducting vortices. The reconstituted chain structures of the magnetic charges in the pinwheel ASI and the strong interaction between magnetic charges and superconducting vortices allow significant modification of the transport properties of the underlying superconducting thin film, resulting in a reprogrammable resistance state that enables a reversible and switchable vortex Hall effect. Our results highlight an effective and simple method of using ASI as an in situ reconfigurable nanoscale energy landscape to design reprogrammable superconducting electronics, which could also be applied to the in situ control of properties and functionalities in other magnetic particle systems, such as magnetic skyrmions.

The actual light absorption photovoltaic responses realized in three-dimensional (3D) radial junction (RJ) units can be rather different from their planar counterparts and remain largely unexplored. We here adopt a laser excitation photoelectric microscope (LEPM) technology to probe the local light harvesting and photoelectric signals of 3D hydrogenated amorphous silicon (a-Si:H) RJ thin film solar cells constructed over a Si nanowire (SiNW) matrix, with a high spatial resolution of 600 nm thanks to the use of a high numerical aperture objective. The LEPM scan can help to resolve clearly the impacts of local structural damages, which are invisible to optical and SEM observations. More importantly, the high-resolution photoelectric mapping establishes a straightforward link between the local 3D geometry of RJ units and their light conversion performance. Surprisingly, it is found that the maximal photoelectric signals are usually recorded in the void locations among the standing SiNW RJs, instead of the overhead positions above the RJs. This phenomenon can be well explained and reproduced by finite element simulation analysis, which highlights unambiguously the dominant contribution of inter-RJ-unit scattering against direct mode incoupling in the 3D solar cell architecture. This LEPM mapping technology and the results help to achieve a straightforward and high-resolution evaluation of the local photovoltaic responses among the 3D RJ units, providing a solid basis for further structural optimization and performance improvement.

In order to obtain high-quality superconducting qubits, we employed a cold-development technique, using temperatures down to −20°C, to fabricate Al/AlOx/Al Josephson junctions. Cold development greatly reduced the sensitivity of the electron-beam resist to the developer, eliminated molecules of the electron-beam resist at trench edges, and improved the repeatability and reliability of the nanopatterning process. The fabricated samples have well-defined geometries and increased dose margins, with lateral sizes of 100 nm×100 nm on both silicon and sapphire substrates. Together with the bridge-free fabrication method we used in these experiments, we believe that the cold-development technique can play an important role in quantum information technology that employs superconducting qubits.

Salmonellais one of the most dangerous and contagious foodborne pathogens, posing a significant threat to public health and food safety. In this study, we developed a click chemistry-based fluorescence biosensing platform for highly sensitive detection of Salmonella enterica(S. enterica) by integrating the trans-cleavage activity of CRISPR/Cas12a with the CLICK17-mediated copper(II)-dependent azide–alkyne cycloaddition (Cu(II)AAC) click reaction. Herein, CLICK-17 can provide binding sites for Cu ions and high redox stability for one or much catalytically vital Cu+within its active sites, which facilitate the click reaction. With the existence of only Cu2+, CLICK17 still can catalyze the click reaction between 3-butyn-1-ol and 3-azido-7-hydroxycoumarin to produce a fluorescence signal. By integrating the recombinase polymerase amplification (RPA), specific recognition, and trans-cleavage ability of the CRISPR/Cas12a system and the CLICK17-catalyzed Cu(II)AAC click reaction, the established biosensor obtained high detection sensitivity. This CLICK17-assisted CRISPR/Cas12a fluorescence biosensor was used for the detection of S. entericawith a limit of detection (LOD) as low as 1 cfu/mL in a wide linear detection range of 6 × 101–6 × 107cfu/mL. Moreover, the developed biosensor exhibited high specificity and anti-interference capability and had a recovery of 93%–104% in detection of S. entericain spiked milk, infant formula, orange juice, and meat samples. This study provides a promising CRISPR/Cas12a-based fluorescence biosensor for the detection of foodborne pathogens.

Personal thermal management technology, which adjusts the heat exchange between the human body and the environment, can passively heat or cool the body to maintain a comfortable core temperature, thereby enhancing comfort and reducing energy consumption. However, most existing personal thermal management materials have static properties, such as fixed solar reflectance and infrared emissivity, which do not support real-time dynamic temperature regulation. Moreover, sweat accumulation on the skin surface, while contributing to temperature regulation, can significantly reduce comfort. This study constructs a unidirectional moisture-permeable intelligent thermal management fabric system to achieve superior thermal and moisture comfort in complex environments. The fabric incorporates thermochromic microcapsules into PAN nanofibers by using electrospinning technology for intelligent thermal management. Subsequent hydrophobic treatment of the fiber film surface imparts the fabric with unidirectional wetting properties. The nanofibrous structure provides intrinsic elasticity and breathability. In heating mode, the fabric’s average sunlight reflectance is 42.1%, which increases to 82.2% in cooling mode, resulting in a reflectance difference of approximately 40%. The hydrophobic treatment endows the fabric with excellent moisture absorption and perspiration properties, demonstrated by a unidirectional moisture transport index of 696.63 and a perspiration evaporation rate of 5.88 mg/min. When the fabric temperature matches the ambient temperature, the photothermal conversion power difference of the Janus metafabric in two modes reaches 248.37 W m–2. Additionally, Janus metafabrics show the potential for temperature-responsive design and repeated writing applications. The outstanding wearability and dynamic spectral properties of these metafabrics open new pathways for sustainable energy, smart textiles, and thermal-moisture comfort applications.

Symmetry breaking plays a pivotal role in unlocking intriguing properties and functionalities in material systems. For example, the breaking of spatial and temporal symmetries leads to a fascinating phenomenon: the superconducting diode effect. However, generating and precisely controlling the superconducting diode effect pose significant challenges. Here, we take a novel route with the deliberate manipulation of magnetic charge potentials to realize unconventional superconducting flux-quantum diode effects. We achieve this through suitably tailored nanoengineered arrays of nanobar magnets on top of a superconducting thin film. We demonstrate the vital roles of inversion antisymmetry and its breaking in evoking unconventional superconducting effects, namely a magnetically symmetric diode effect and an odd-parity magnetotransport effect. These effects are nonvolatilely controllable through in situ magnetization switching of the nanobar magnets. Our findings promote the use of antisymmetry (breaking) for initiating unconventional superconducting properties, paving the way for exciting prospects and innovative functionalities in superconducting electronics.

A conspicuous feature of the amyotrophic lateral sclerosis (ALS)-associated protein SOD1 is that its maturation into a functional enzyme relies on local folding of two disordered loops into a catalytic subdomain. To drive the disorder-to-order transition, the protein employs a single Zn2+ion. The question is then if the entropic penalty of maintaining such disordered loops in the immature apoSOD1 monomer is large enough to explain its unusually low stability, slow folding, and pathological aggregation in ALS. To find out, we determined the effects of systematically altering the SOD1-loop lengths by protein redesign. The results show that the loops destabilize the apoSOD1 monomer by ∼3 kcal/mol, rendering the protein marginally stable and accounting for its aggregation behavior. Yet the effect on the global folding kinetics remains much smaller with a transition-state destabilization of <1 kcal/mol. Notably, this 1/3 transition-state to folded-state stability ratio provides a clear-cut example of the enigmatic disagreement between the Leffler α value from loop-length alterations (typically 1/3) and the “standard” reaction coordinates based on solvent perturbations (typically >2/3). Reconciling the issue, we demonstrate that the disagreement disappears when accounting for the progressive loop shortening that occurs along the folding pathway. The approach assumes a consistent Flory loop entropy scaling factor of c= 1.48 for both equilibrium and kinetic data and has the added benefit of verifying the tertiary interactions of the folding nucleus as determined by phi-value analysis. Thus, SOD1 not only represents a case where evolution of key catalytic function has come with the drawback of a destabilized apo state but also stands out as a well-suited model system for exploring the physicochemical details of protein self-organization.

We investigated the superconducting properties of Fe1+yTe0.6Se0.4single-crystalline microbridges with a width of 4 μm and thicknesses ranging from 20.8 to 136.2 nm. The temperature-dependent in-plane resistance of the bridges exhibited a type of metal-insulator transition in the normal state. The critical current density (Jc) of the microbridge with a thickness of 136.2 nm was 82.3 kA/cm2at 3K and reached 105 kA/cm2after extrapolation to T= 0 K. The current versus voltage characteristics of the microbridges showed a Josephson-like behavior with an obvious hysteresis. These results demonstrate the potential application of ultra-thin Fe-based microbridges in superconducting electronic devices such as bolometric detectors.

PEGylation is the most widely used method to chemically modify protein biopharmaceuticals, but surprisingly limited public data is available on the biophysical effects of protein PEGylation. Here we report the first large-scale study, with site-specific mono-PEGylation of 15 different proteins and characterization of 61 entities in total using a common set of analytical methods. Predictions of molecular size were typically accurate in comparison with actual size determined by size-exclusion chromatography (SEC) or dynamic light scattering (DLS). In contrast, there was no universal trend regarding the effect of PEGylation on the thermal stability of a protein based on data generated by circular dichroism (CD), differential scanning calorimetry (DSC), or differential scanning fluorimetry (DSF). In addition, DSF was validated as a fast and inexpensive screening method for thermal unfolding studies of PEGylated proteins. Multivariate data analysis revealed clear trends in biophysical properties upon PEGylation for a subset of proteins, although no universal trends were found. Taken together, these findings are important in the consideration of biophysical methods and evaluation of second-generation biopharmaceutical drug candidates.

The dependence of terahertz (THz) emission power on the thickness of series Bi2Sr2CaCu2O8 (BSCCO) mesas is studied in this letter. An intrinsic Josephson junction (IJJ) array with two BSCCO mesas in series is proposed. The current-voltage characteristics of the IJJs, the powers, and Fourier spectra of the THz emission are measured for different thicknesses of the mesas, which is gradually mounted by the argon ion beam milling. Experiment results indicate that the THz emission power grows as the thickness of the mesas is increasing. The power reaches a maximum value of about 0.502 μW at a frequency of 0.708 THz when the thickness is 1200 nm. However, the THz emission power decreases while the thickness of the mesas keeps increasing. This nonlinearity between the THz emission power and the thickness of the mesas is due to the cavity resonance of the mesas and the self-heating generated by the IJJs in the mesas. The structure of connecting two mesas in series can be extended to form an IJJ array of multiple series mesas, which could further improve the THz emission power.

A superconducting integrated receiver (SIR) comprises all of the elements needed for heterodyne detection on a single chip. Light weight and low power consumption combined with nearly quantum-limited sensitivity and a wide tuning range of the superconducting local oscillator make the SIR a perfect candidate for many practical applications. For the first time, we demonstrated the capabilities of the SIR technology for remote operation under harsh environmental conditions and for heterodyne spectroscopy at atmospheric limb sounding on board a high-altitude balloon. Recently, the SIR was successfully implemented for the first spectral measurements of THz radiation emitted from intrinsic Josephson junction stacks (BSCCO mesa) at frequencies up to 750 GHz; linewidth below 10 MHz has been recorded in the high bias regime. The phase-locked SIR has been used for the locking of the BSCCO oscillator under the test. To extend the operation range of the SIR well above 1 THz, a new technique for fabrication of high-quality SIS tunnel junctions with gap voltage Vg up to 5.3 mV has been developed. Integration of a superconducting high-harmonic phase detector with a cryogenic oscillator opens a possibility for efficient phase locking of the sources with free-running linewidth up to 30 MHz that is important both for BSCCO mesa and NbN/MgO/NbN oscillators.

This study addresses the stratigraphic architecture and connectivity of fluvial sandstones of the Williams Fork Formation through outcrop analysis, and static and dynamic modelling of equivalent reservoirs in the Piceance Basin, Colorado. The Williams Fork Formation is a succession of fluvial channel sandstones, crevasse splays, floodplain mudstones and paludal coals that were deposited by meandering- and braided-river systems within coastal- and alluvial-plain settings.Three-dimensional (3D) static and dynamic reservoir models that are constrained to both outcrop-derived and subsurface data show how static connectivity is sensitive to sandstone-body type and width, and varies with net to gross ratio. Connectivity analyses of 3D outcrop-based architectural-element models show how relatively wide sandstone bodies enhance connectivity. At Mamm Creek Field, connectivity of sandstones that are pay within the middle Williams Fork Formation is 12–18% higher than for the lower Williams Fork Formation. For highly constrained 3D object-based models of architectural elements, connectivity is only 4% higher when crevasse splays are included as reservoir-quality sandstones. Dynamic simulation results also suggest that the best history match is possible by considering only point bars and channel bars (reservoir-quality sandstones) as pay. Additional research is necessary to determine the impact of crevasse splays on reservoir connectivity.

To investigate the detailed junction properties of intrinsic Josephson junctions (IJJs) in YBa2Cu3O7?X(YBCO) without shunted grain boundaries and with good uniformity, we fabricated sub-micron sized IJJs in a YBCO whisker by using a focused-ion-beam etching. The sub-micron sized junctions showed clear multiple branches with a hysteresis structure in the current-voltage curve, like IJJs in Bi2Sr2CaCu2O8+X. The temperature dependence of the critical current demonstrates that the junction behaviour drastically changes from that of an SNS type to an SIS type when the critical temperature is decreased. The critical current density of the junctions, in the order of 10-100 kA cm?2, corresponds to Josephson plasma frequencies from a few hundred GHz to 1-2 THz.

This paper investigates the temperature dependence of microwave surface resistance (RS) of YBa2Cu3O7-x(YBCO) thin films with different microstructures at 10 GHz, using a coplanar resonator technique. YBCO thin films with different grain sizes were obtained as a result of changing the quenching procedure after film deposition by dc sputtering. The value of RSwas found to vary with varying surface morphology and can be explained by the coupled grain model (CGM) when a temperature-dependent grain boundary resistance (R) is used. The temperature (T) dependence of Ris given by R=R0+C(T/TC)2T, where TCis the superconducting critical temperature, and R0and Care the fitting parameters, depending on the properties of each sample.