Fig. 1. Two sources, one surface. Where crests meet, the waves add; where a crest meets a trough, the surface stays quiet. Move a source and the quiet lines redraw themselves. An illustrative model, not a result from a paper.
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This master's thesis asks how CERN's 'scientists-as-guides' at the Science Gateway exhibitions differ from typical science museum educators, what challenges they face in unstructured, walk-up conversations with visitors, and whether a targeted training can help. It builds a new theoretical lens, Science Museum Didactic Transposition (SMDT), adapting Chevallard's and Brousseau's classroom theory to museum exhibits, and uses it with field notes, observations and interviews of four guides, SEEZ software tracking of three guides and a survey of 56 guides (measured, Aug–Nov 2025) to identify three
The study asks whether a flexible poly(vinylidene fluoride) (PVDF) film filled with 4 wt% three-dimensional zinc oxide tetrapods (ZnO-Ts) can kill bacteria on demand when it is bent, shaken or exposed to ultrasound, so that skin-contact wearables resist bacterial build-up without leaching antimicrobial agents. In measured laboratory tests against E. coli, the composite reached >98% bactericidal efficiency under mechanical stimulation and >90% under ultrasonic stimulation, produced a stronger hydroxyl-radical (TPA fluorescence) signal than unstimulated films, plain PVDF or ZnO-nanoparticle film
The paper asks what a coding-agent 'harness' is — the runtime that couples a large language model to the world through a loop, tools, context management, safety controls, orchestration and extension surfaces — and how production harnesses are actually built. It is a descriptive source-code study (not a benchmark) of eleven systems pinned to July 2026 releases (Claude Code, Codex CLI, Gemini CLI, Mistral Vibe, OpenHands, Aider, Mini-SWE-Agent, Hermes, Pi, OpenCode, OpenClaw), plus the Omnigent meta-harness as a contrast point. Contributions: a seven-subsystem reference anatomy with minimal and
The paper asks how a base station can obtain the benefits of a large near-field antenna array while activating only a small fraction of its antennas, without the mechanical complexity of movable antennas. The authors propose reconfigurable array thinning: a full half-wavelength array stays fixed while RF switches activate a subset (32 of 320 in the simulations). Analytically and numerically they show that uniform sparse arrays produce grating lobes in the angle domain but not along range, then design two particle-swarm-optimized thinned arrays: GTA, pre-optimized to suppress angular grating lo
A Science Perspective (commentary) by Radlinski and Bäumler on the study by Spragge et al. (Science 382, eadj3502, 2023), which asked what makes a gut microbiota protective against infection. Through in silico and in vitro analysis of the carbon sources used by members of defined bacterial communities, together with mouse experiments, Spragge et al. reported that complex communities provide colonization resistance by depleting all the nutrients an opportunistic pathogen such as Klebsiella pneumoniae, or a pathogen such as Salmonella Typhimurium, needs to grow. A single closely related 'keyston
The paper asks how a touch-based (tactile) sensor could capture high-resolution 3D surface geometry continuously over large industrial parts, instead of the slow press-and-lift measurements of conventional vision-based tactile sensors, whose frame cameras also blur at speed. The authors built a roller sensor: a soft, reflective-coated elastomer on a transparent acrylic cylinder, viewed from inside by a stationary neuromorphic (event) camera, and mounted it on a UR10 robot arm. They reconstruct 3D depth with an event-based multi-view stereo (EMVS) method adapted to the roller and extended with
The paper asks how many radio-frequency (RF) chains a wideband hybrid antenna array needs to cancel beam split, the frequency-dependent drift of a beam's focal point in angle and, in the radiative near field, in distance. It analytically separates near-field beam split into an angular part (identical to far-field beam squint) and a radial part that vanishes beyond a derived boundary; derives near-field instantaneous-bandwidth expressions and proposes an algorithm for the RF chain count of sub-connected arrays; and shows, via the eigenspectrum of the space-frequency correlation matrix, that a f
The authors ask whether Bessel beams — light beams that keep a narrow central spot (or, for high orders, a dark-centred ring) over long distances — can be generated directly at the tip of a standard single-mode optical fiber with designable properties. They propose and fabricate, by two-photon-lithography 3D printing in a single step on the fiber facet (and, for characterization, on cover glass), a stacked micro-structure: a tapered photonic-crystal-fiber-like aligner, a fractal-PCF inverse taper that turns the fiber mode into an annular beam of chosen radius, an optional spiral phase plate, a
The paper asks whether an optical microcomb can directly produce a broadband, coherent millimetre-wave (sub-terahertz) frequency comb rather than a single microwave tone. In experiments, the authors feed the ~50 GHz (48.9 GHz) pulse train of a laser cavity-soliton microcomb into commercial photoconductive antennas and measure, by time-domain spectroscopy, single-cycle millimetre-wave pulses whose spectrum is a comb with ~50 GHz spacing, more than 600 GHz of bandwidth, ten resolvable harmonics and zero carrier-envelope offset. A free-running single soliton (~5 mW optical, <1.5 W electrical) dro
A laser fusion rocket would make thrust by letting fusion-heated plasma push against a magnetic nozzle, so its performance must be extrapolated from laboratory-scale experiments. This experimental study fired a Nd:YAG laser (15–480 mJ) at a carbon target 15 mm in front of a pulsed solenoid coil mounted on a torsional thrust stand, measuring the impulse delivered to the coil and imaging the plasma emission with a gated ICCD camera over magnetic-to-laser energy ratios of 0.040–3.4. Measured results: at 480 mJ, the changes in impulse bit and early-phase expansion radius are correlated (a stronger
The paper asks whether an architected (mechanical) metamaterial can be designed so that, under a single steady load direction, its sideways deformation abruptly reverses in a user-specified, time-ordered sequence — i.e., a Poisson’s ratio that alternates between positive and negative values over time and, in graded lattices, across space. The authors combine the outward-facing beams of a regular honeycomb with the inward-facing beams of a re-entrant (negative-Poisson’s-ratio) honeycomb, give the two beam families different stiffnesses, and add six self-contacting hard stops; as the cell is loa
A tutorial from the LIGO Project on Pound-Drever-Hall (PDH) laser frequency stabilization: how to hold a laser's frequency steady by comparing it with a Fabry-Perot cavity. The research question is pedagogical: how and why the PDH error signal works, and what fundamentally limits it. The laser is phase-modulated to create sidebands; the light reflected from the cavity is detected and demodulated with a mixer, giving an error signal that is zero on resonance and whose sign shows which side of resonance the laser is on, and this is fed back to the laser. The paper builds a conceptual (slow-dithe
Can surface shape alone make a water-loving resin repel water? The authors used two-photon polymerisation to print arrays of mushroom-shaped (MS), inverted-crown (ICM) and multi-crown (MCM) micro-pillars on hydrophilic OrmoComp, whose flat surface has a measured water contact angle of 61.5°. Measured: the MCM design, which adds 1 µm secondary pillars on each cap, reached a 151° contact angle and a 9° sliding angle at 20 µm spacing without any low-surface-energy coating; contact angles fell for all designs as spacing grew to 50 µm. Mainly 2D two-phase flow simulations, with one 3D check, indica
The paper asks how to put a single, trustworthy number on how 'localized' (concentrated in a small region) a function such as a wave's intensity is. The authors show that popular measures built only from Lebesgue norms, such as the participation ratio alpha_{2,4} and mass-concentration comparisons, cannot tell apart functions made of the same values in different places (e.g. two narrow steps moved further apart). They propose a new localization coefficient beta, the Wasserstein-2 (optimal transport) distance between the normalised function and the uniform distribution on the domain, and prove
The study asks how two-photon polymerization can print open, fully 3D fibrous cage scaffolds for cell culture without the unintended directionality caused by the laser's vertically elongated voxel and by proximity effects between neighbouring writing lines. Using OrmoComp resist, the authors experimentally characterized single-line and five-line beams, then fabricated beams as evenly spaced (0.3 µm) hollow elliptical shells flattened to offset voxel elongation, with a centre-out writing order and laser power calibrated to increase from the bottom to the top of ~150 µm cages. SEM measurements s
The paper asks how to make the modified Born series (an iterative sum of repeated scattering terms with a complex relaxation parameter) converge for high-frequency, strongly scattering Helmholtz problems in one, two and three dimensions, where the classical Born series diverges because the scattering operator's spectral radius exceeds one. The authors propose selecting a single complex relaxation parameter from an estimated spectrum: eigenvalues precomputed for a constant reference medium are propagated along a homotopy to the radial medium profile using a leading-order WKB approximation, whic
This perspective, building on the SusML workshop in Dresden, asks how machine learning can explore molecules and materials while limiting the energy and carbon cost of the whole AI-driven discovery pipeline, from quantum-mechanical (QM) data generation and model training to self-driving laboratories. Using the Green Algorithms calculator on compute resources reported in each study, the authors estimate carbon footprints for benchmark QM datasets and AI models (Table 1, Fig. 1): generating large QM datasets is estimated to emit up to tens of thousands of tonnes CO2e, whereas training general-pu
The authors asked whether the Zeeman splitting of visible spectral lines can serve as a non-intrusive way to measure the magnetic field inside a laser-produced plasma. At the LULI2000 laser facility they drove blast waves in 8 mbar air inside a pulsed Helmholtz coil (5–20 T, oriented parallel or perpendicular to the spectrometer line of sight) and recorded time-resolved emission from singly ionized nitrogen (563–574 nm) with a 0.195 nm resolution spectrometer. They measured splitting that depends on field orientation: viewed along the field only the σ components appear and the 567.96 nm line v
The study asks how the thickness, and therefore the thermal mass, of screen-printed Bi–Sb–Te thermoelectric films affects their performance as self-powered photo-thermoelectric infrared sensors. The authors tuned film thickness through ink solvent content (35, 25 and 20 wt% solvent gave measured thicknesses of about 12, 23 and 30 µm). They printed single-legged p-type, single-legged n-type and double-legged (p + n) sensors on 50 µm Kapton and characterised their optics, microstructure, bending stability and thermoelectric properties. Under a 10.6 µm CO2 laser, the measured output rose with las
The authors ask whether poly(2-oxazoline) (POx) cross-linkers can serve as resins for two-photon polymerization (2PP) printing of micro-scale hydrogel scaffolds whose surface chemistry is set after printing. They synthesized two cross-linkers with piperazine acrylamide end groups, one with ethyl side chains (B-Et-PipA) and one with amine side chains (B-Am-PipA), and printed them with a ~780 nm femtosecond laser (20 mW, 10 mm/s) into cuboids and 125 µm grids with 10 or 25 µm openings and 1-3 layers. Measured characterization showed uniform printed structures, swelling ratios of 1.6 and 2.2, and
The paper asks whether a compact, fully three-dimensional metasurface can act as a broadband quarter-wave plate for terahertz (THz) light in reflection, replacing millimetre-thick birefringent crystals. The authors print a 60 × 60 array of L-shaped polymer meta-atoms (period 218 μm, height 75 μm) on silicon by two-photon polymerization direct laser writing (Nanoscribe Photonic Professional GT+, IP-Q resin, 780 nm femtosecond laser, 10× objective), then coat them with 200 nm of gold by normal- and oblique-incidence magnetron sputtering. Reflection-mode THz time-domain spectroscopy measurements,
The study asks how two-photon lithography can print microscale kinematic pairs (joints whose parts move relative to each other) already assembled, without sacrificial support pillars. The authors formulate a two-photon epoxy photoresist (TPEO) that becomes solid-like after prebaking, with measured yield stresses of 1048–9084 Pa versus 4.68 Pa for a commercial resist, so unsupported printed voxels stay where they are written; an in situ development step then grafts a fluorosilane (FDTS) self-assembled monolayer that lowers the measured surface free energy from 43.4 to 14.9 mN/m and the ball-on-
This review asks how complex 3D microstructures made of glass, ceramics, metals and carbon can be fabricated with sub-micron resolution. It consolidates published work on "thermal-treatment-assisted" two-photon lithography: a femtosecond laser first writes a polymeric or hybrid "green body" scaffold voxel by voxel through nonlinear two-photon absorption, and pyrolysis, annealing or sintering then removes the organic part and converts the scaffold into an inorganic part. The authors compare precursor families (silica-hybrid, PDMS/POSS/PSQ, HSQ and liquid-silica resins for glass; polymer-derived
Two-photon lithography (TPL) prints submicron 3D structures but cannot easily make overhanging or suspended features, because microscale supports are hard to remove afterwards. The authors formulate a water-soluble (W-S) photoresist from hydrophilic monomers (DAC, NVP, NIPAAm, PAAc with the photoinitiator BEBP) and use it to print sacrificial supports. Measured results: blocks print well between about 16 and 52 mW at 80 mm/s; 100 x 100 x 30 um blocks dissolved within 7 min and most complex microstructures within 10 min in static room-temperature water, and within 4 min in 45 C or flowing water
Experimental study asking how a sustainable triboelectric nanogenerator (TENG) can be made both stronger and practically usable. The authors grow bacterial cellulose from food-waste media, load it with neem-extract-synthesized silver nanoparticles, and pair it with PTFE in a 4 cm x 4 cm contact-separation TENG. Measured: the 5 wt% Ag film gives the best output (1264 V open-circuit, 60 uA short-circuit, 13.53 W/m2 peak at 60 MOhm) versus 450 V and 17.6 uA for pristine cellulose; lower and higher loadings perform worse, attributed to dielectric gains versus particle aggregation and leakage. A pa
The paper asks whether amorphous silicon can supply both intrinsic near-infrared light emission and a compact optical cavity for integrated photonics. Solution-synthesized amorphous silicon microspheres (about 500-1400 nm across) show measured room-temperature whispering-gallery-mode photoluminescence with sharp resonances spanning 800-1100 nm and a maximum measured quality factor of 522, whereas fractured spheres give only broad, weak emission. Finite-element simulations assign the peaks to TE and TM modes. The measured emission red-shifts with temperature (0.05 nm/K), with the surrounding re
The study asks why filling-phase simulations of micro-injection moulding disagree with real parts, using a screwless two-plunger machine moulding miniature POM dog-bone specimens. Experimentally, the authors characterised piston speed, estimated piston pressure, switch-over behaviour and decompression across a full-factorial set of melt temperature, mould temperature and injection speed, and measured short shots. They found that the plunger overtravels its nominal switch-over position (about 0.8 mm at 100 mm/s up to about 3.3 mm at 200 mm/s), whereas decompression length mattered much less. Si
The paper asks whether momentum-space (back focal plane) spectroscopy can be done without a bulky microscope objective and at many sample positions at once. The authors print ellipsoidal IP-Dip microlenses directly onto optical microcavities by two-photon polymerization lithography (Nanoscribe Photonic Professional) and show experimentally that each lens acts as an independent optic with a numerical aperture of about 0.95: measured reflectivity and photoluminescence dispersions are collected from SiO2/TiO2, GaAs and CdTe cavities, including at 4.5 K in a cryostat with simple low-NA relay optic
The study asks how light-based vat-photopolymerisation can make high-resolution hydrogel structures whose composition and stiffness are controlled both during and after printing. Experimentally, the authors formulate GelMA and 4-arm-PEG-acrylate resins, print them by projection micro-stereolithography (features down to about 20 µm, with cavity size set by light power) and show the same GelMA formulations print as sharp honeycombs on a two-photon polymerisation printer. Swapping the resin vat mid-print gives multimaterial parts with bonded interfaces; the tartrazine photoabsorber washes out whi
This review asks how resin chemistry, two-photon lithography (2PL) printing parameters, environment and post-processing set the mechanical behavior of laser-printed microstructures, with emphasis on Young's modulus. It compiles published measurements showing that 2PL photoresists span roughly eight orders of magnitude in stiffness, from kPa hydrogels to silica-like GPa materials, and that laser power, scan speed, slicing/hatching, water immersion, UV post-curing and pyrolysis can shift a given material's modulus by up to about an order of magnitude. It then compares surface methods (nanoindent
This experimental study asks how conformal thin films can be lithographically patterned on the exterior surfaces of complex 3D micro- and nanostructures. The authors introduce Scaffold-Architected Lift-Off (SALO): sacrificial scaffold masks are printed directly onto the 3D surface by two-photon polymerization (Nanoscribe Photonic Professional GT2, IP-Dip resist), the whole sample is coated by sputtering, evaporation or atomic layer deposition, and the scaffolds are then removed mechanically by sonication in isopropanol, where cavitation microjets lever them off at their weakly adhering base. T
The study asks how the shape and spacing of artificial dendritic spines steer neurons during their first days of growth. Using two-photon polymerization (Nanoscribe Photonic Professional GT, IP-Dip resin, dip-in laser lithography), the authors printed arrays of thin, stubby and mushroom-shaped micropillars at high, medium and low density (pitches of 4, 10 and 30 µm) on fused silica, coated them with poly-L-lysine and cultured primary chicken-embryo cortical neurons on them. Measured outcomes include 24-h brightfield time-lapse tracking of neurite direction and speed, growth-cone morphology at
This qualitative case study asks how software professionals experience a coordinated, management-mandated roll-out of AI development tools at a large Swedish telecommunications company, and how they expect their profession to change. Semi-structured interviews with 12 professionals at three sites, conducted about six months into the roll-out and analyzed with process coding and thematic analysis (six themes, 663 theme assignments), describe the tools as helpful but fallible: useful for writing code, tests, search and documentation, but limited on large, specialized code bases and always requir
This experimental study asks how tilting a three-dimensional scaffold changes exchange bias in a magnetic bilayer coated onto it. Two-photon lithography prints 20 µm-long, 1 µm-wide polymer microwire scaffolds inclined at 0°, 30° and 45°; magnetron sputtering then coats them with CoFe (ferromagnet) / IrMn (antiferromagnet) stacks, and dark-field magneto-optical Kerr effect magnetometry measures single wires alongside the surrounding planar film. On smooth scaffolds the measured exchange-bias field rises from about 25 mT (0°) to about 39 mT (45°), and coercivity also increases. Plotted against
The study asks how permanent micro-magnets can be built into polymer microrobots during two-photon polymerization (TPP) instead of being inserted or aligned afterwards. The authors glue magnets into printed fixtures that hold their poles in a set orientation, calibrate the printer origin to a magnet corner, and print each robot body directly around its magnet in either Dip-in Laser Lithography (taller single-magnet robots) or oil-immersion mode (multi-magnet robots needing precise alignment). A 0.5 µm DC-sputtered tantalum coating lets initially uncoated 100 µm NdFeB magnets be encapsulated: m
This experimental study asks how chemical fixation changes what label-free stimulated Raman scattering (SRS) microscopy measures in cells. The authors acquired hyperspectral SRS images in the C–H stretching region (2820–3012 cm⁻¹) of 2,325 cultured HeLa cells, either live or fixed with 1.5% glutaraldehyde, 4% paraformaldehyde, 10% neutral buffered formalin, 70% ethanol or methanol, and compared spectral shape, lipid (2850 cm⁻¹) and protein (2920 cm⁻¹) band intensity, cell area and lipid spatial distribution. They measured that formaldehyde-based fixatives best preserve spectral shape and lipid
The study asks how to rapidly identify which fuel-tank microorganisms drive or inhibit microbiologically influenced corrosion of carbon steel, and through which metabolites. It presents DURABLE, a laboratory workflow combining 16S rRNA/ITS amplicon sequencing of six biofilm samples from two mock diesel tanks (hydro-processed renewable diesel and petroleum F76), agarose gel-droplet single-cell isolation, a 96-well carbon steel bead colorimetric screen, coupon weight-loss tests, whole-genome sequencing, untargeted metabolomics and electrochemical validation. In measured experiments, 84 isolates
Hall and colleagues 3D-printed two hollow cylindrical bellows microsprings (~100 µm diameter) from the same print file using two-photon polymerization in IP-Dip resin, then compressed them with a flat-punch nanoindenter. The measurements show that the springs are roughly ten times stiffer than earlier two-photon-printed microsprings (~1500–4000 µN/µm) but not Hookean: each has distinct linear and nonlinear stiffness regions that differ between the two nominally identical samples; they keep sinking (creep) under constant load, with drift rates that rise with load and fall with hold time; under
This experimental study asks how the composition (Ba4Co2Fe36−xAlxO60 with x = 0.0 or the Al3+-substituted x = 1.0) and loading (20 or 200 mg per 10 mL ink) of U-type hexaferrite particles change extrusion-printed gelatin–alginate scaffolds, compared with a particle-free control. Measured results: all inks were shear-thinning and printed square grids with acceptable printability (Pr 0.91–1.07, no significant differences); the 200 mg loadings reinforced the network (significantly higher consistency index, G′ above G″ up to 35.5 °C); the low-loading Al-substituted ink gave the highest swelling (1
The paper asks whether adding horizontal scaffold arms between vertical pillars can concentrate light strongly enough to make nitrogen-vacancy (NV−) centres in nanodiamonds emit faster, as a route to brighter 3-D quantum sensors. In finite-element (COMSOL) simulations of a 3.1 µm unit cell at the NV− zero-phonon line (637 nm), pillars alone give a flat Purcell response near 1, while an emitter at a scaffold joint reaches simulated peak Purcell factors of about 2 (polymer, SiC) to about 4 (silicon), rising to roughly 17–20 with a 50 nm silver coating; enhancement is largest for dipoles aligned
The paper asks whether the phase structure of the driving laser can steer electrons inside a laser wakefield accelerator. At the ZEUS laser facility, the authors measured electron beams driven by a Gaussian pulse and by a Laguerre-Gaussian (m = 1) pulse carrying orbital angular momentum, made with a removable spiral phase mirror. Both drivers produced 300-550 MeV electrons; the twisted driver gave two separated beamlets (20-40 mrad apart), about half the charge and much weaker betatron X-rays. Fourier-Bessel particle-in-cell simulations reproduce the split and attribute it to two rotating azim
Can a flat liquid-crystal (LC) diffractive lens have a smooth, continuous phase profile and still be switched electrically? The authors used two-photon polymerization direct laser writing inside a 20 µm cell of polymerizable nematic LC (78 wt% E7, 20 wt% RM257, 1 wt% IR819), held homeotropic at 100 Vpp during writing, to lock polymer regions of designed height and thereby sculpt wrapped Fresnel zone plate (FZP) phase profiles. Polarized optical and digital holographic microscopy confirmed the intended profiles. In measurements, a 2π-wrapped plate focused at 0 Vpp, switched off at 10 Vpp, and g
The study asks whether an on-chip hollow-core waveguide can keep guiding light when most of its membrane cladding is removed, so that diffusing molecules can reach the core from the side. Using two-photon-polymerization 3D nanoprinting (Nanoscribe GT2, IP-Dip2 resist), the authors fabricate two 'Photonic Scaffold' geometries with cladding-openness fractions up to 80%. A resonator-based model (simulated) attributes guidance to anti-resonant confinement combined with Bloch-mode formation and predicts losses at or below about 1 dB/mm even at 80% openness. Measured cut-back losses for 68% openness
Conventional Bayer colour-filter mosaics absorb out-of-band light and typically pass only about 30% of incident white light, which limits low-light colour imaging. The authors ask whether a low-refractive-index polymer (IP-L resin, n ≈ 1.52), long considered too weak for compact spectral routing, can instead redirect colours to their RGGB subpixels. They inverse-design (particle swarm optimisation with a max–min objective, full-wave FDTD) a 2.5D unit cell of four cylindrical nanopillars of different heights and diameters and print 1 × 1 mm² arrays (500 × 500 unit cells) in a single step by two
The study asks how a simple, manufacturable polymer metalens can bring the blue, green and red light of a compact near-eye display to a single focus. The authors print cylindrical IP-Dip2 nanopillars at a 450 nm period by two-photon lithography, setting diameter with laser power and height with stacked voxels, and build a library of printable pillars. A differentiable library-based inverse design (ring-wise top-K phase preselection, hard Gumbel-Softmax selection with straight-through gradients, and a minimax objective on the worst-color focusing efficiency) chooses one pillar per radial ring.
The study asks whether the screw-like coxa-trochanteral leg joints of weevils are isolated mechanical extremes, discrete adaptive types, or part of a broader continuum. Using synchrotron X-ray micro-CT of the middle-leg joint in 68 species from seven family-level groups, landmark-free atlas-based morphometrics, robust 3D helix fits and phylogenetic comparative analyses, the authors measured that trochanter shape varies continuously with broad family overlap, while only 7 of 16 possible combinations of four joint characters occur (a coxal thread never occurs without a trochanteral helix). True
The paper asks whether 3D-printed, gold-coated nanocones that resonate at about 1 THz can outperform conventional non-resonant metal nanotips as out-of-plane, field-driven electron emitters. Using two-photon 3D printing, the authors fabricate a single resonant nanocone, a dense cone array, a 'cooperative' array whose 200 µm spacing couples each cone's resonance to the lattice resonance, and a single cone among resonant cylinders, plus a 1-mm non-resonant reference tip. COMSOL simulations predict peak field enhancements of about 900, 1850 and 6800 for the single cone, array and cooperative arra
Can a microscope restore sharp images of objects whose distance from the focal plane is unknown? The authors design a circularly symmetric phase mask for the Fourier plane of a 4f microscope so that the point spread function becomes a nearly defocus-invariant, Bessel-like beam, and they jointly optimize the mask profile (a 20-term polynomial) with a Richardson-Lucy deconvolution accelerated by a Wiener-Butterworth back projector, using simulated blur and shot noise on ImageNet-Sketch training images in TensorFlow. The mask is fabricated by two-photon grayscale lithography (Nanoscribe Quantum X
Can two-photon polymerization (2PP) build miniaturized liquid-chromatography columns whose flow channels and interaction surfaces are set independently? The authors developed a photoresin of pentaerythritol tetra-acrylate with 5% dodecyl methacrylate (a nonpolar functional monomer) and 30% butyl benzoate as porogen, and used 2PP to print cylindrical monoliths (3 mm long, 350 um wide) from a CAD lattice of Schoen gyroid cells (20 um cell, 7.5 um channels, 6.2 um struts, 70% designed macroporosity). Polymerization-induced phase separation produced 10-100 nm mesopores (SEM), while nano-CT measure
The study asks how to program liquid-crystal molecular alignment throughout fully three-dimensional microstructures made by two-photon polymerization (direct laser writing), where earlier alignment methods were limited to films, surface layers or isolated filaments. The authors show experimentally that, after each laser-written line or layer, unpolymerized liquid-crystal monomers diffuse toward the fresh polymer interface and reorient perpendicular to it; if the laser returns only after this has happened, the new orientation is locked in. Choosing the stacking direction and the inter-line or i
Can a 3D lattice scaffold be designed so that one property changes while the others stay nearly fixed? The authors parameterize a symmetric strut-based unit cell by strut angle, strut length and strut diameter, compute mechanical properties (Poisson's ratio, elastic and shear moduli, Zener anisotropy) and morphometric properties (relative mass density, pore sizes, surface-to-volume ratio, tortuosity) for 44,837 designs by voxel-based numerical homogenization, and search all ~1.0 billion design pairs for pairs that contrast one property while the others stay within a tolerance. In simulation, P
High-speed experiments in 50/50 wt DMSO/water mixtures examine bubble bursting at the critical conditions (Bond number near 0, Laplace number near La* ≈ 1110) that produce the smallest and fastest first jet droplet, and measure how trace surfactant changes it: Tween 80, and the weaker SDS as a stand-in for natural impurities. In the measurements, concentrations that barely change the equilibrium surface tension still increase the first-droplet radius and reduce its velocity. For Tween 80 at c/ccmc = 0.0233 (σ/σc = 0.98) the radius rises by a factor of 2.8 (volume about 20-fold), the number of
The study asks whether 3D-printed surface topography can control how human cortical organoids are positioned on a substrate, how tightly they attach, and which way their neurites grow. Using two-photon polymerization (Nanoscribe GT2, IP-Q resin) the authors printed millimetre-scale cultivation platforms on 12 mm coverslips or silicon, anchored by printed cones plus capillary-wicked PDMS to stop shrinkage-induced detachment. In experiments after 14 days of culture, funnels and slopes positioned organoids (median shift 167 µm from the intended spot, n = 9), rods were embedded or wrapped by the o
The study asks how to metallize and selectively insulate complex 3D-printed neural probes without lithographic masks. Two-photon polymerization prints a 7.26-mm device with a 2-mm penetrating shank and four mushroom-shaped electrodes. Undercut trenches restrict line-of-sight Ti/Pt evaporation to the trench floors, and capillary-driven SU-8 fills the trenches but stops at the electrodes' convex edges. Measured trace resistances of a few ohms, open circuits between adjacent pads, SEM imaging, cyclic voltammetry and impedance spectra before and after insertion, and a measured insertion force of a
Research question: how can newcomers reproducibly build, align and mode-lock a compact bow-tie (ring) Ti:sapphire femtosecond laser, a task the authors say is well covered in theory but poorly documented in practice? Contribution: an experimental guide that compiles the design calculations (ray-transfer-matrix stability, Kerr-lens sensitivity near the stability limit, astigmatism-compensation angle, dispersion compensation with dispersion-compensating mirrors, Peltier thermal control) and a step-by-step alignment and scanning procedure that moves mirror M2 and the crystal toward mirror M1 unti
The paper revisits the Elitzur-Vaidman bomb-testing thought experiment, in which a single photon in a Mach-Zehnder interferometer can reveal that a photon-triggered bomb sits in one arm without being absorbed by it. It derives the theoretical outcome probabilities for 50/50 beam splitters (bomb triggered 1/2, each detector 1/4) and reviews proposed and previously reported quantum-Zeno variants in which N repeated looks raise the success probability to [cos^2(pi/2N)]^N. The authors' own work is a qualitative HeNe-laser Mach-Zehnder demonstration and quantum-circuit simulations run through Qiski
The study asks whether multicomponent (high-entropy) ceramics can be 3D-printed at the nanoscale and whether their chemical disorder makes ceramic nanolattices both strong and damage tolerant. The authors developed transparent, solvent-free metal-acrylate photoresins (more than 15 metals, up to 70 wt% metal acrylates) for two-photon polymerization, then used a two-step sintering schedule (1300 °C then 1200 °C) and sacrificial spring supports to obtain fully dense, high-fidelity (Ba0.2Sr0.2Ca0.2La0.2Mg0.2)TiO3 perovskite architectures with features down to about 150 nm. Measured TEM analysis sh
The paper asks whether ferroelectric barium titanate (BTO) phase shifters can remove the static-power and thermal-crosstalk barrier that limits scaling of heater-based programmable photonic circuits. The authors fabricated a hybrid silicon–BTO hexagonal waveguide mesh with 58 programmable unit cells, 116 actuators and 34 optical ports on 2×10 mm². Measurements on individual unit cells show ~82 ns rise/fall times, 560 nW per π static consumption in volatile (Pockels) mode, and non-volatile operation in which 300 ns pulse trains set ferroelectric domain configurations that persist with the bias
This UCLA PhD dissertation asks how two-photon lithography (TPL), a laser 3D-printing method with sub-micron resolution, can overcome three limits: printing one material at a time with low throughput, being unable to deform parts while printing them, and being unable to assemble and join micro-parts. It builds and experimentally demonstrates three hybrid systems. (1) Scanning two-photon continuous flow lithography steers the femtosecond laser to follow particles in a flowing resin; it printed ~50 um bi-material cell-carrier particles at 10 particles per second, with a bead-labelled shelter reg
Stimulated Raman scattering (SRS) microscopy can suffer from a spurious, non-chemical background caused by cross-phase modulation (XPM), normally suppressed by collecting the transmitted beam with high-NA objectives or condensers whose millimetre-scale working distance is incompatible with stage-top incubators used for live-cell time-lapse imaging. The authors designed by ray tracing and fabricated by two-photon lithography a 1.2 NA catadioptric thin lens (about 6 mm wide, 270 um thick) combining a refractive Fresnel centre with total-internal-reflection prisms at the edge. Measured SRS spectr
The paper asks whether the radio emission at twice the plasma frequency (2ωp) seen in solar type-III bursts can be reproduced and diagnosed in the laboratory. In space this emission is thought to arise when a Langmuir wave driven by a flare electron beam decays into a nearly counter-propagating Langmuir wave plus an ion acoustic wave, and the two Langmuir waves then coalesce. At the LULI2000 facility the authors replace the electron beam with a laser (500 J, 2 ns, 526 nm) crossing a plasma made by exploding a 4 µm plastic foil. Backward stimulated Raman scattering drives the primary Langmuir w
The researchers asked whether light scattered by stimulated Raman scattering (SRS) in a laser-produced plasma can be bright enough to undergo Raman scattering a second time. Theorists had long predicted this 'rescattering' in simulations for inertial confinement fusion, but nobody had observed it. Firing a 500 J, 2 ns, 526 nm laser beam (average intensity about 1e14 W/cm2, speckles near 1e15 W/cm2) into a hydrogen gas jet at the LULI2000 facility, they measured time-resolved spectra at five angles. Near the laser axis they found an extra signal at frequency close to omega0 - 2 omega_p, the sig
The paper asks how well large language models (LLMs) and people can combine familiar ideas in unfamiliar ways. It introduces KOMBINE, an open-ended benchmark that hands random pairs of unrelated, recognizable entities (283 entries across 21 domains, drawn from Wikidata) to solvers and asks for three kinds of combination: an association (a factual chain of triples linking the pair), an analogy (two paths with an identical relation sequence, used to invent a concept by projecting structure across the mapping) and a blend (a shared abstract 'generic space' plus a fused concept with structure from
Ultrathin lensless endoscopes built from multicore fibers form a focus by co-phasing the beams from many widely spaced single-mode cores, but because the cores fill only a small part of the fiber face, even perfect co-phasing leaves most light in a speckle halo (a focal-spot power ratio of about 0.01 reported for earlier bare-fiber systems). The authors design and 3D print, by two-photon lithography directly on a 180 µm, 120-core Fermat-spiral multicore fiber, a miniature 'hyper-telescope': one microlens per core expands and collimates each beamlet to fill the pupil, and a single top lens refo
The paper asks whether a hyperdimensional classifier whose learned parameters are low-bit angles (a 'phase memory') can be trained while storing nothing but the model, instead of also keeping an optimizer's records of past gradients. It proposes Phase-HDC, which turns each stored angle by at most one notch per update, against the sign of the current minibatch gradient and only when the gradient magnitude exceeds a threshold, and proves this rule is the exact minimizer of a first-order loss model with a fixed cost per changed parameter. In a controlled experiment on scikit-learn handwritten dig
The paper asks whether a practical single-axis acoustic levitator can be built without the high-voltage, hand-matched and temperature-sensitive Langevin horns used by previous designs. The authors design, build and evaluate TinyLev, a non-resonant levitator made of 72 low-cost, low-voltage (ca. 20 V) 40 kHz ultrasonic transducers arranged in two 3D-printed curved bowls and driven by an Arduino and a motor-driver board. Simulations (piston-source field and Gor'kov force) guided the transducer arrangement and bowl radius; experiments measured the minimum excitation voltage needed to hold samples
The paper asks whether artificial cilia can approach natural cilia in size, speed, 3D non-reciprocal motion, individual control, durability and compatibility with salty water. The authors report (measured) that acrylic acid-co-acrylamide hydrogel microcilia (2–10 µm wide, 18–90 µm tall), 3D-printed by two-photon polymerization with nanometre-scale pores, bend in response to 1.5 V without electrolysis because cations migrate inside the gel: H+ accumulation shrinks the cathode-facing side in deionized water (bending toward the cathode), whereas Na+ drags water and swells it in physiological sali
Two-photon lithography (TPL) writes 3D micro-structures with ~100 nm resolution but is normally run open-loop, so part dimensions drift during long sessions. The authors built a TPL platform around a single-cavity dual-comb laser: one comb, frequency-converted to 800 nm, writes, while the dual-comb pair performs spectrally encoded in-situ phase measurements of the curing photoresist at ~360 Hz. Because cured resin has a higher refractive index, the measured phase gives part height (about 0.207 rad per µm; 4.8 nm height sensitivity at 2 s averaging). A dynamic dose model fed by these measuremen
The paper asks whether structuring a solid target on the nanoscale can give in-situ, sub-femtosecond and nanometre-scale control over the relativistic electrons produced when an intense femtosecond laser hits it. In measurements with p-polarized 25 fs, 800 nm pulses at 3 × 10^18 W cm^-2 on arrays of silicon nanopillars (period 720 nm, height 700 nm), rear-side electrons above 100 keV formed a guided beam whose direction changed with the laser's angle of incidence (15°, 25°, 40°), with a 20–35° angular width versus about 60° from a flat target, about twice the rear flux, and a measured cutoff e
The study asks why atomically precise gold nanoclusters print inconsistently by two-photon lithography and whether a physical descriptor can predict printability. Measured milligram-scale rheology of six Au25/Au38 thiolate clusters shows a transition from solid to viscoelastic solid to viscoelastic liquid as the ligand-length-to-core-diameter ratio (L/D) rises from 0.45 to 1.32; molecular-dynamics simulations of four model systems link this to free volume and diffusion. Using a bis(fluorophenyl azide) crosslinker and a 515 nm femtosecond laser, photogenerated nitrenes covalently staple ligand
The study asks which molecular features make renewable, terpene-derived acrylate monomers printable by two-photon polymerisation (2PP). Using oxidative chemistry (ozonolysis, osmium-catalysed dihydroxylation, diol cleavage) followed by T3P-mediated acrylation, the authors synthesised four new multi-acrylates from alpha-pinene diol, nopol and verbenol (alpha-PDA, NTA, VDA, VTA). They then printed micro-topographies (Topo 990, Topo 27) and a university logo, and examined them by scanning electron microscopy. Measured outcomes: alpha-PDA, a runny diacrylate, could not be printed at any tested con
Kim and Saha ask how projection two-photon lithography, which prints whole layers at once through a binary (on/off) digital micromirror device, can set the light dose of each focal spot independently without slowing down. They introduce grayscale projection two-photon lithography on a custom-built printer: each focal spot is written by a 7×7-pixel binary motif about the size of the diffraction-limited spot (785 nm), so switching pixels off dims the spot without shrinking it. Fourier-optics simulations of 8,192 four-fold-symmetric motifs selected 32 intensity levels (100% to 10%); measured spot
The study asks how maskless digital projection lithography, which normally cannot separate dense lines once their pitch falls below roughly the diffraction limit, can print dense subwavelength line patterns. The authors cascade an amplitude-type and a phase-type liquid-crystal spatial light modulator (8 µm pixels, aligned pixel-to-pixel through a 1:1 4F relay) to form a programmable alternating phase-shift mask, and project it with 517 nm femtosecond pulses through a 100x, NA 1.40 oil objective onto AR-N 7520 resist exposed by two-photon absorption. A π phase difference between neighbouring li
The study asks how to pattern temperature-sensitive biopolymer hydrogels with two-photon, sub-micrometer precision at a throughput useful for tissue engineering. In a femtosecond projection two-photon lithography setup (a micromirror device projects whole cross-sections), the authors replace cleavage-type photoinitiators, which they report char the hydrogel before it polymerizes, with a Type II Eosin Y/triethanolamine system. Measured spectroscopy (fluorescence lifetimes, nanosecond flash photolysis, absorption changes) indicates triethanolamine quenches Eosin Y's singlet and triplet states to
Organ-on-chip experiments usually depend on incompatible, closed peripheral equipment, which makes models hard to combine or move between labs. The authors build and test STARTER, a stand-alone platform in which pumps, reservoirs, in-line sensors and three organ-on-chips mount as ISO 22916-compliant building blocks (following the openly published TOP Design Rules) on a microplate-sized fluidic circuit board; every channel runs to a single swappable routing block, so replacing that one part reconfigures the fluidic circuit without tubing. They demonstrate, with measurements, parallel and combin
In two-photon polymerization (TPP), the laser dose sets the resin's degree of conversion and with it properties such as refractive index (RI), but standard design files carry only geometry and dose-to-property calibration is hard. The authors present an open-source MATLAB slicer that converts a voxelized 3D RI map into a list of x, y, z and laser-power instructions for a Nanoscribe printer, and a calibration method using two-immersion digital holographic microscopy on a shell-protected step structure, which removes the need to measure sample height. Measured results for IP-Dip2 cover RI from a
The authors ask how the electron-donating branches of three branched, quasi-centrosymmetric quadrupolar diquinoxalines (DQ-IMD, DQ-DDA, DQ-DPA) control their two- and three-photon absorption, and whether the molecules work as two-photon polymerization photoinitiators. Measured linear spectroscopy, solvatochromism and absolute multiphoton-excited fluorescence (2PA 550–1000 nm, 3PA 1000–1180 nm in dichloromethane), interpreted with (TD-)DFT calculations and a sum-over-states model, show that 2PA bands sit apart from 1PA bands as expected for near-centrosymmetric molecules, and that the excited s
The study asks whether five compact push–pull dyes, aryltricyanoethylenes (naphthalene, anthracene, phenanthrene, pyrene or perylene donors joined to a tricyanoethylene acceptor), can initiate radical photopolymerization of the acrylate monomer PETA. Measured absorption, electrochemistry, LED photobleaching, FTIR polymerization kinetics and EPR spin trapping show that the dyes work with the amine DMCHA and/or an iodonium salt. AntTCNE/DMCHA gave the fastest two-component one-photon polymerization, and three-component dye/amine/iodonium systems were faster still. The authors propose a mechanism
Experimental communication asking whether a spatial light modulator (SLM) used in image mode can raise the throughput of two-photon polymerization (2PP) by projecting a whole pattern into the resin in one exposure instead of writing with a single focal spot. With a 515 nm femtosecond laser (<200 fs, 1-5 MHz), a Holoeye 1920 x 1080 SLM, a x40 / NA 0.95 objective and OrmoComp resin made sensitive to 515 nm with 2% Irgacure OXE02, the authors printed square boxes, pillar arrays and rings at a fixed focal z, setting structure size only through pulse energy and exposure time. Measured results: box
Can a sub-millimetre robot copy the jet propulsion of squids and octopuses without copying their soft anatomy? The authors 3D-print, by direct laser writing, CeFlowBot: a ~420 × 500 µm two-lobed body with six tilted cylindrical cavities (L = 100 µm) that trap air bubbles and flank an open inner channel. Under sound the bubbles vibrate and drive acoustic streaming that pumps fluid from the wide inlet to the tapered outlet; a 2D simulation and tracer-particle experiments agree on this flow. Measured speeds peak near 1.9 mm/s at about 40.5 kHz (80 Vpp drive) and rise steeply with drive voltage. A
Imaging individual neurons deep in the brain requires implanting a gradient-index (GRIN) rod, but ultrathin (0.35–0.5 mm) rods have intrinsic optical aberrations that keep only the centre of the field of view sharp. The authors designed aspheric corrective lenses by optical simulation and fabricated them with two-photon lithography (3D micro-printing), then replicated them onto the coverslip above the rod, so the probe needs no change to a standard two-photon microscope. Simulations predicted a 2–9× larger diffraction-limited field of view; bead measurements showed a 3.2–9.4× larger effective
The study asks whether low-cost printed sensors, whose resistor is a biodegradable PHBV/carbon composite that soil microbes digest, can serve as an in-situ proxy for biological soil health. In the first multi-plot field deployment, 44 sensors were buried for 50 days (summer 2023) in a long-term grassland restoration experiment at Colt Park Meadows, UK, logging resistance every 30 minutes; 31 passed quality filtering. The rate of resistance rise, and in a separate analysis the number of detected changepoints, were compared with laboratory measurements from soil cores. All three statistical appr
The paper asks whether low-cost printed sensors can track soil microbial decomposition continuously and without digging the soil up. Each sensor is a printed resistor made from an ink of PHBV, a biodegradable polymer, mixed with carbon flake. As soil microbes degrade the PHBV it swells and pushes the carbon particles apart, so the resistance rises; the rate of that rise is used as a proxy for microbial activity. The sensors were tested in a polytunnel mesocosm experiment with 36 intact cores: species-rich grassland soil versus winter wheat soil, each under drought, flood or control watering, w
The researchers test whether a printed carbon–biopolymer trace can act as an electronic indicator of microbial decomposition activity. They print carbon flakes in a biodegradable PHBV binder on glass, record electrical resistance in compost tea and soil, and compare soil responses with independently measured carbon dioxide release. Active compost tea produces a strong resistance rise while sterile controls change little. Wet/dry electrical measurements and thickness profiles support binder degradation and increased swelling as a likely mechanism. After 14 days, soil sensors show mean resistanc
The paper asks how a purely mechanical circuit can pass a binary signal through connected logic and memory so that it travels only from input to output (non-reciprocal) yet can be undone by reversing the input (reversible). The authors design compliant cross-pivot flexure memory bits with equal, symmetric energy wells, chain them with a step-wise decrease in energy barrier along the signal path, and add a purpose-built AND gate whose rotation suppresses the output unless both inputs agree; a compression spring impedance-matches the gate to downstream bits. A generalized dynamics model (simulat
This theoretical study derives general cutting rules for quantum electrodynamics in a plane-wave background and checks their application to trident electron–positron pair production in a constant crossed field. The authors compare a direct tree-level calculation with cuts of a two-loop electron-scattering contribution, provide initial-spin-resolved direct and exchange rates, and numerically compare integrated one-step terms. The two-step terms coincide analytically; the one-step numerical results agree within the stated numerical accuracy. Recovering a correct differential distribution from an
The researchers measured three embalming-residue samples from two Egyptian crocodile skulls using infrared spectroscopy, ultrahigh-resolution FTICR mass spectrometry, and GC-MS. FTICR MS assigned 3,169–6,944 molecular formulae and revealed oxidized pine-resin fingerprints; GC-MS structurally identified 109 compounds overall and additionally detected bitumen biomarkers. Combining the methods supported pine resin, beeswax, fats/oils and bitumen in the residues. Formula matches alone are tentative identifications, and the resin changes reflect heating and/or ageing rather than a uniquely determin
How quickly can electron-seeded matter–antimatter avalanches grow in realistic intense laser fields? The authors derive a general analytical growth-rate model that includes electrons, positrons and photons escaping from the strongest-field region. Comparisons with Monte Carlo and particle-in-cell simulations support its predictions, including a focus-dependent onset threshold and a high-field regime where local production dominates escape. The model also estimates conditions for dense pair plasma and screening of the generating field. It assumes a cascade can reach a quasisteady state and seed
Photonic crystal fibers (PCFs) steer light with patterns of microscopic air channels, but they are normally drawn from a heated preform, which distorts hole patterns, rules out some geometries and makes µm-precise short segments very hard to make. The authors show that high-resolution two-photon 3D printing can build PCF-design waveguide segments directly, in one step, on the end of a standard single-mode fiber. They print five PCF classes (highly nonlinear, helically twisted coreless, photonic-bandgap hollow-core, anti-resonant hollow-core, fractal ring-core) and measure the expected guided m
The paper asks how strongly an applied magnetic field can suppress electron heat conduction in a laser-heated plasma, and whether the temperature gain keeps growing with field strength. In experiments on a hydrogen gas jet in fields up to 20 T, Thomson scattering measured a peak electron temperature about 1.4 times higher than without a field. The gain saturates from 10 T, a Hall parameter near 50, consistent with analytical estimates and Vlasov-Fokker-Planck simulations. Limitation: the saturated state lasts only about 0.5 ns before the density cavitates and heating falls.
The researchers fabricate a disconnected three-dimensional artificial spin ice inspired by the pyrochlore lattice, using two-photon lithography, pyrolysis and magnetic thin-film deposition to place tilted nanomagnets at four heights. Magnetic force microscopy identifies single-domain, s- and vortex states; micromagnetic calculations explain how dimensions influence these textures, and a point-dipole calculation shows how tilt changes vertex energy ordering. Synchrotron imaging improves structural visibility but does not reliably determine the magnetic configuration. Uniform single-domain array
A simulation study asking how the water cycle of a tidally-locked, Earth-like planet depends on its total, finite inventory of water. Using nine idealised general circulation model runs (Isca) with a 'bucket' land hydrology — initial global water depths of 1, 10 and 100 m and three evaporation thresholds — the authors find that every simulated world evolves toward an 'eyeball' state with a barren day side and water cold-trapped on the night side, but that a lake just east of the substellar point can form first and persist for 150–350 years (1 m), 1000–1300 years (10 m) or about 8000 years (100
Can a standard scanning electron microscope reveal very fast mechanical motion? The authors time-tag secondary electrons and sort repeated drive cycles into phase-resolved movies of quartz and an AFM cantilever assembly. The quartz benchmark demonstrates about 3 nm spatial and 3 ns temporal tracking jitter. Effective frame spacing is independent of raster speed; reconstruction requires reproducible motion and takes minutes to hours.
Microscopes trade resolution, field of view and frame rate against the sensor's limited pixel throughput. The authors build and experimentally demonstrate a microscope that treats a 6 × 8 array of 48 sensors as one large 'super sensor' (active pixels cover only ~22% of its area) and place a fabricated 64-level diffractive optical element in the pupil that turns each point into 15 spots, so every sample position sends light to at least one sensor. A sparsity- and total-variation-regularized reconstruction with a fully shift-variant convolutional forward model then recovers a gap-free image, ext
Using observed Trackinsight ETF holdings and primary-market flows from June 2020 onward, the authors examine how cumulative ETF pressure relates to next-month stock returns. For U.S. thematic and sectoral ETFs they identify negative short-horizon and positive nine-to-twelve-month associations, then combine standardized twelve-month and three-month pressures into a stock-ranking signal evaluated in hypothetical historical and January–August 2026 post-sample portfolios. The dataset does not cover all global ETF assets, and the simple portfolio construction has substantial turnover. European equi
The researchers experimentally reprogram one thin-film lithium-niobate slab waveguide to route spatial modes, sort beam shapes, multiply intensity vectors by matrices, and control wavelength response. Projected illumination changes the refractive-index landscape, while physics-aware training combines measured outputs with gradients from a calibrated beam-propagation model. Demonstrated functions include four- and eight-mode permutations, broadband operation at 1500–1600 nm, and separation of 1310 nm and 1550 nm. The present index contrast of about 1.7 × 10⁻³ limits device compactness and trans
Measurements of eight frog neural crest cell clusters migrating toward stiffer gel reveal asymmetric height profiles with rearward peaks. The authors extend active-wetting theory so basal cell motion drives internal flow, pressure differences and surface curvature, and fit the numerical model to the averaged measured profile. The fit gives a capillary number of 0.29 ± 0.03 and an estimated viscosity of about 8.2 kPa·s. The viscosity estimate depends on the assumed amplitude of basal velocity variations, which were not directly measured.
This literature review maps artificial intelligence and machine learning across the composite-material lifecycle. A bibliometric analysis counts 1,474 publications from 2010–2025 in seven journals, complemented by a technical review of over 200 studies in the supplied author-submitted manuscript. Mechanics and failure dominate research volume, and the review connects methods to design, manufacturing, performance, monitoring and sustainability tasks. Its synthesis emphasizes physics integration, uncertainty quantification and sensing to address limited generalization from simulations or small d
This review synthesizes artificial intelligence applications in additive manufacturing across lightweight design, in situ monitoring, energy optimization, and cost-effective manufacturing. It reports results from separate prior studies and proposes a four-stage closed-loop framework connecting design, process planning, production, and continuous model updating, with an infrastructure stack and implementation roadmap. The integrated framework is proposed; many reviewed models remain limited to particular machines, materials, or simulated datasets, and cross-machine closed-loop validation remain
This experimental study measures lateral shear adhesion of IP-S two-photon-polymerized microstructures on plasma-activated silicon, ITO-coated glass, MAPTMS-silanized silicon and SU8-coated silicon. SU8 interlayers give higher peak forces and retain more normalized adhesion after acetone exposure, while rounded structures improve adhesion on substrates showing interfacial failure. Finite-element simulations connect the geometry effect to residual stress. The measured conclusions concern the tested resin, geometries and processing protocols; SU8 geometry comparisons were excluded because partia
This experimental study asks whether custom solid microstructures can be fabricated directly inside living cells. The authors microinject photoresist into HeLa cells and use two-photon polymerization to print approximately 10-micrometer structures, including graphical barcodes and diffraction gratings. Separate whole-droplet single-photon curing produces intracellular microlasers. Confocal imaging and electron microscopy characterize the structures, and cellular observations show division and altered division times. The method is a proof of concept in individually handled cells; injection and
The paper introduces a pathway-first construction for freeform photonic interconnects in nearly hyperuniform dielectric slabs. Fixed, staggered offset points are embedded in a background relaxed under a periodic repulsive potential, then tessellated into dielectric networks. Finite-difference time-domain simulations predict low excess routing loss for specific designs within a confined-mode spectral window. Silicon near-infrared transmission and scaled ceramic microwave measurements support guided transport; microwave field mapping shows confinement along a curved route. Low-loss operation req
Can miniature optics printed directly on a single-mode fiber tailor both bright-centered and vortex Bessel beams? The authors fabricate a three-segment polymer photonic structure using two-photon lithography and experimentally demonstrate zeroth-order and high-order beams, including topological charges up to 20. Analytical relations connect printed geometry to beam width and diffraction-free distance. Many beam characterizations use structures printed on cover glass; the polymer may constrain operation in harsh environments.
This preprint asks which known mechanisms could increase deuterium fusion rates in solids at ambient conditions. It reviews atomic screening and proximity, nuclear resonances, and coherent quantum dynamics, and supplies model calculations and a research roadmap for combining enhancements. The large combined enhancements are conditional theoretical estimates, not a measured demonstration of ambient-temperature fusion or useful energy production; key low-energy resonances and collective coupling assumptions require experimental validation.
Can programmable optical nodes reduce the digital equalization burden in long-haul spatial division multiplexing? The authors develop a differentiable transmission model that optimizes photonic unitary transformations and implement them on a silica photonic processor. A three-mode recirculating-fibre experiment reaches 1,331.2 km and reduces the reported delay spread from approximately 25 ns to 10 ns compared with an identity transformation; simulations also examine ten modes.
Almost entirely empty space. Still full of possibility. Explore a foam made of palladium nanowires—and discover how it holds hydrogen inside the metal itself.
This preprint tests two PAMGuard location pipelines with simulated whale calls and reports large errors under several uncertainties. Explore the seven scenarios, two different error metrics, and how clock differences enter the geometry.
Imagine giving a clue that reveals the answer to you but leaves someone else guessing. Can a teacher learn to choose better clues while making room for students to ask? Balzan and colleagues tested this in a computer game where learners could use different identifying traits. Their simulations found that learning about group needs improved efficiency, while student questions enabled everyone to identify the target under the model’s rules. The work suggests a mechanism worth testing in education, but it has not been validated in classrooms.
When AI agents talk, agreement is only half the story. A group can average to zero because everyone is unsure—or because two camps are absolutely convinced.
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