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This technical report investigates the integration of generative AI (GenAI), specifically ChatGPT, into the practice of ethical hacking through a comprehensive experimental study and conceptual analysis. Conducted in a controlled virtual environment, the study evaluates GenAI's effectiveness across the key stages of penetration testing on Linux-based target machines operating within a virtual local area network (LAN), including reconnaissance, scanning and enumeration, gaining access, maintaining access, and covering tracks. The findings confirm that GenAI can significantly enhance and streamline the ethical hacking process while underscoring the importance of balanced human-AI collaboration rather than the complete replacement of human input. The report also critically examines potential risks such as misuse, data biases, hallucination, and over-reliance on AI. This research contributes to the ongoing discussion on the ethical use of AI in cybersecurity and highlights the need for continued innovation to strengthen security defences.

Analogously to de Bruijn sequences, orientable sequences have application in automatic position-location applications and, until recently, studies of these sequences focused on the binary case. In recent work by Alhakim et al., a range of methods of construction were described for orientable sequences over arbitrary finite alphabets; some of these methods involve using negative orientable sequences as a building block. In this paper we describe three techniques for generating such negative orientable sequences, as well as upper bounds on their period. We then go on to show how these negative orientable sequences can be used to generate orientable sequences with period close to the maximum possible for every non-binary alphabet size and for every tuple length. In doing so we use two closely related approaches described by Alhakim et al., Comment: Minor bugs fixed

In the field of detection and ranging, multiple complementary sensing modalities may be used to enrich the information obtained from a dynamic scene. One application of this sensor fusion is in public security and surveillance, whose efficacy and privacy protection measures must be continually evaluated. We present a novel deployment of sensor fusion for the discrete detection of concealed metal objects on persons whilst preserving their privacy. This is achieved by coupling off-the-shelf mmWave radar and depth camera technology with a novel neural network architecture that processes the radar signals using convolutional Long Short-term Memory (LSTM) blocks and the depth signal, using convolutional operations. The combined latent features are then magnified using a deep feature magnification to learn cross-modality dependencies in the data. We further propose a decoder, based on the feature extraction and embedding block, to learn an efficient upsampling of the latent space to learn the location of the concealed object in the spatial domain through radar feature guidance. We demonstrate the detection of presence and inference of 3D location of concealed metal objects with an accuracy of up to 95%, using a technique that is robust to multiple persons. This work provides a demonstration of the potential for cost effective and portable sensor fusion, with strong opportunities for further development.

How does the genome encode the form of the organism? What is the nature of this genomic code? Common metaphors, such as a blueprint or program, fail to capture the complex, indirect, and evolutionarily dynamic relationship between the genome and organismal form, or the constructive, interactive processes that produce it. Such metaphors are also not readily formalised, either to treat empirical data or to simulate genomic encoding of form in silico. Here, we propose a new analogy, inspired by recent work in machine learning and neuroscience: that the genome encodes a generative model of the organism. In this scheme, by analogy with variational autoencoders, the genome does not encode either organismal form or developmental processes directly, but comprises a compressed space of latent variables. These latent variables are the DNA sequences that specify the biochemical properties of encoded proteins and the relative affinities between trans-acting regulatory factors and their target sequence elements. Collectively, these comprise a connectionist network, with weights that get encoded by the learning algorithm of evolution and decoded through the processes of development. The latent variables collectively shape an energy landscape that constrains the self-organising processes of development so as to reliably produce a new individual of a certain type, providing a direct analogy to Waddingtons famous epigenetic landscape. The generative model analogy accounts for the complex, distributed genetic architecture of most traits and the emergent robustness and evolvability of developmental processes. It also provides a new way to explain the independent selectability of specific traits, drawing on the idea of multiplexed disentangled representations observed in artificial and neural systems and lends itself to formalisation., Comment: 31 pages, 4 figures

We describe new, simple, recursive methods of construction for orientable sequences over an arbitrary finite alphabet, i.e. periodic sequences in which any sub-sequence of n consecutive elements occurs at most once in a period in either direction. In particular we establish how two variants of a generalised Lempel homomorphism can be used to recursively construct such sequences, generalising previous work on the binary case. We also derive an upper bound on the period of an orientable sequence., Comment: Minor bugs fixed

As an embodied and spatial medium, virtual reality is proving an attractive proposition for robot teleoperation in hazardous environments. This paper examines a nuclear decommissioning scenario in which a simulated team of semi-autonomous robots are used to characterise a chamber within a virtual nuclear facility. This study examines the potential utility and impact of sonification as a means of communicating salient operator data in such an environment. However, the question of what sound should be used and how it can be applied in different applications is far from resolved. This paper explores and compares two sonification design approaches. The first is inspired by the theory of cognitive metaphor to create sonifications that align with socially acquired contextual and ecological understanding of the application domain. The second adopts a computationalist approach using auditory mappings that are commonplace in the literature. The results suggest that the computationalist approach outperforms the cognitive metaphor approach in terms of predictability and mental workload. However, qualitative data analysis demonstrates that the cognitive metaphor approach resulted in sounds that were more intuitive, and were better implemented for spatialisation of data sources and data legibility when there was more than one sound source., Comment: Accepted for publication in Frontiers in Virtual Reality->Technologies for VR under the research topic 'Interactive Audio Systems and Artefacts within Extended Reality: Innovation, Creativity and Accessibility'

We study the partitioning of motile bacteria into different thermodynamic states of a phase-separated dextran (DEX)/polyethylene glycol (PEG) aqueous mixture. While non-motile bacteria partition exclusively into the DEX-rich phase in all conditions tested, we observed that motile bacteria transverse the soft DEX/PEG interface and partition variably among the two phases. For our model organism \textit{Bacillus subtilis}, the fraction of motile bacteria in the DEX-rich phase increased from 0.58 to 1 as we increased DEX composition within the two-phase region. We hypothesized that the chemical affinity between dextran and the bacteria cell wall acts to weakly confine the bacteria within the DEX-rich phase; however, motility can generate sufficient mechanical forces to overcome the soft confinement and propel the bacteria into the PEG-rich phase. Using optical tweezers to drag a bacterium across the DEX/PEG interface, we developed a model to predict the overall phase partitioning based on a competition between the interfacial forces and bacterial propulsive forces. Our measurements are supported by a theoretical model of dilute active rods embedded within a periodic soft confinement potential., Comment: 4 pages, 3 figures, See Supporting Information in ancillary files (1 appendix, 3 movies)

The spin-orbit splitting between neutron 1$p$ orbitals at $^{33}$Si has been deduced using the single-neutron-adding ($d$,$p$) reaction in inverse kinematics with a beam of $^{32}$Si, a long-lived radioisotope. Reaction products were analyzed by the newly implemented SOLARIS spectrometer at the reaccelerated-beam facility at the National Superconducting Cyclotron Laboratory. The measurements show reasonable agreement with shell-model calculations that incorporate modern cross-shell interactions, but they contradict the prediction of proton density depletion based on relativistic mean-field theory. The evolution of the neutron 1$p$-shell orbitals is systematically studied using the present and existing data in the isotonic chains of $N=17$, 19, and 21. In each case, a smooth decrease in the separation of the $1p_{3/2}$-$1p_{1/2}$ orbitals is seen as the respective $p$-orbitals approach zero binding, suggesting that the finite nuclear potential strongly influences the evolution of nuclear structure in this region., Comment: 10 pages, 5 figures

This paper re-examines the security of three related block cipher modes of operation designed to provide authenticated encryption. These modes, known as PES-PCBC, IOBC and EPBC, were all proposed in the mid-1990s. However, analyses of security of the latter two modes were published more recently. In each case one or more papers describing security issues with the schemes were eventually published, although a flaw in one of these analyses (of EPBC) was subsequently discovered - this means that until now EPBC had no known major issues. This paper establishes that, despite this, all three schemes possess defects which should prevent their use - especially as there are a number of efficient alternative schemes possessing proofs of security., Comment: Minor typos fixed

Real-life bacteria often swim in complex fluids, but our understanding of the interactions between bacteria and complex surroundings is still evolving. In this work, rod-like \textit{Bacillus subtilis} swims in a quasi-2D environment with aqueous liquid-liquid interfaces, i.e., the isotropic-nematic coexistence phase of an aqueous chromonic liquid crystal. Focusing on the bacteria motion near and at the liquid-liquid interfaces, we collect and quantify bacterial trajectories ranging across the isotropic to the nematic phase. Despite its small magnitude, the interfacial tension of the order of 10 $\mathrm{\mu N/m}$ at the isotropic-nematic interface justifies our observations that bacteria swimming more perpendicular to the interface have a higher probability of crossing the interface. Our force-balance model, considering the interfacial tension, further predicts how the length and speed of the bacteria affect their crossing behaviors. We also find, as soon as the bacteria cross the interface and enter the nematic phase, they wiggle less, but faster, and that this occurs as the flagellar bundles aggregate within the nematic phase.

The guiding and transport of energy, for example of electromagnetic waves underpins many technologies that have shaped modern society, ranging from long distance optical fibre telecommunications to on-chip optical processors. Traditionally, a mechanism is required that exponentially localises the waves or particles in the confinement region, e.g. total internal reflection at a boundary. We introduce a waveguiding mechanism that relies on a different origin for the exponential confinement and that arises due to the physics of diffusion. We demonstrate this concept using light and show that photon density waves can propagate as a guided mode along a core-structure embedded in a scattering, opaque material, enhancing light transmission by orders of magnitude and along non-trivial, e.g. curved trajectories. This waveguiding mechanism can also occur naturally, for example in the cerebral spinal fluid surrounding the brain, along tendons in the human body and is to be expected in other systems that follow the same physics e.g. neutron diffusion.

The $g$ factors of $11/2^-$ isomers in semimagic $^{109}$Sn and $^{111}$Sn (isomeric lifetimes $\tau = 2.9(3)$ ns and $\tau = 14.4(7)$ ns, respectively) were measured by an extension of the Time Differential Perturbed Angular Distribution technique, which uses \LaBr detectors and the hyperfine fields of a gadolinium host to achieve precise measurements in a new regime of short-lived isomers. The results, $g(11/2^-; {^{109}\textrm{Sn}}) = -0.186(8)$ and $g(11/2^-; {^{111}\textrm{Sn}}) = -0.214(4)$, are significantly lower in magnitude than those of the $11/2^-$ isomers in the heavier isotopes and depart from the value expected for a near pure neutron $h_{11/2}$ configuration. Broken-symmetry density functional theory calculations applied to the sequence of $11/2^-$ states reproduce the magnitude and location of this deviation. The $g(11/2^-)$ values are affected by shape core polarization; the odd $0h_{11/2}$ neutron couples to $J^{\pi}=2^+,4^+,6^+...$ configurations in the weakly-deformed effective core, causing a decrease in the $g$-factor magnitudes., Comment: 8 pages, 7 figures. Accepted in Physics Letters B

Flare frequency distributions represent a key approach to addressing one of the largest problems in solar and stellar physics: determining the mechanism that counter-intuitively heats coronae to temperatures that are orders of magnitude hotter than the corresponding photospheres. It is widely accepted that the magnetic field is responsible for the heating, but there are two competing mechanisms that could explain it: nanoflares or Alfv\'en waves. To date, neither can be directly observed. Nanoflares are, by definition, extremely small, but their aggregate energy release could represent a substantial heating mechanism, presuming they are sufficiently abundant. One way to test this presumption is via the flare frequency distribution, which describes how often flares of various energies occur. If the slope of the power law fitting the flare frequency distribution is above a critical threshold, $\alpha=2$ as established in prior literature, then there should be a sufficient abundance of nanoflares to explain coronal heating. We performed $>$600 case studies of solar flares, made possible by an unprecedented number of data analysts via three semesters of an undergraduate physics laboratory course. This allowed us to include two crucial, but nontrivial, analysis methods: pre-flare baseline subtraction and computation of the flare energy, which requires determining flare start and stop times. We aggregated the results of these analyses into a statistical study to determine that $\alpha = 1.63 \pm 0.03$. This is below the critical threshold, suggesting that Alfv\'en waves are an important driver of coronal heating., Comment: 1,002 authors, 14 pages, 4 figures, 3 tables, published by The Astrophysical Journal on 2023-05-09, volume 948, page 71

Superconductor-semiconductor nanowire hybrid structures are useful in fabricating devices for quantum information processing. While selective area growth (SAG) offers the flexibility to grow semiconductor nanowires in arbitrary geometries, in-situ evaporation of superconductors ensures pristine superconductor-semiconductor interfaces, resulting in strong induced superconductivity in the semiconducting nanowire. In this work, we evaporated islands of superconductor tin on InAs SAG nanowires, by using in-situ shadowing with high aspect-ratio pre-fabricated SiOx dielectric walls. Our technique allows complete customization of each physical parameter of such hybrid nanostructures, while performing the nanowire and superconductor growths without breaking vacuum. Using this technique, we grew super(S)-normal(N)-super(S) (SNS), NS and SNSNS junctions. We performed cryogenic electron transport measurements revealing the presence of gate and field tunable supercurrents in shadow junctions fabricated on in-plane SAG nanowires. We further measured the superconducting gap and critical fields in the hybrid nanostructures and the crossover from 2e to 1e periodicity in the SNSNS junctions, as a proof of the usability of these hybrid nanostructures.

The only proposed observation of a discrete, hexacontatetrapole ($E6$) transition in nature occurs from the T$_{1/2}$ = 2.54(2)-minute decay of $^{53m}$Fe. However, there are conflicting claims concerning its $\gamma$-decay branching ratio, and a rigorous interrogation of $\gamma$-ray sum contributions is lacking. Experiments performed at the Australian Heavy Ion Accelerator Facility were used to study the decay of $^{53m}$Fe. For the first time, sum-coincidence contributions to the weak $E6$ and $M5$ decay branches have been firmly quantified using complementary experimental and computational methods. Agreement across the different approaches confirms the existence of the real $E6$ transition; the $M5$ branching ratio and transition rate have also been revised. Shell model calculations performed in the full $pf$ model space suggest that the effective proton charge for high-multipole, $E4$ and $E6$, transitions is quenched to approximately two-thirds of the collective $E2$ value. Correlations between nucleons may offer an explanation of this unexpected phenomenon, which is in stark contrast to the collective nature of lower-multipole, electric transitions observed in atomic nuclei., Comment: 9 pages, 4 figures, to be published in Physical Review Letters

The design and performance of a new Compton-suppressed HPGe and charged-particle array, CLARION2-TRINITY, are described. The TRINITY charged-particle array is comprised of 64 Cerium-doped Gadolinium Aluminium Gallium Garnet (GAGG:Ce) crystals configured into five rings spanning 7-54 degrees, and two annular silicon detectors that can shadow or extend the angular coverage to backward angles with minimal $\gamma$-ray attenuation. GAGG:Ce is a non-hygroscopic, bright, and relatively fast scintillator with a light distribution well matched to SiPMs. Count rates up to 40 kHz per crystal are sustainable. Fundamental characteristics of GAGG:Ce are measured and presented, including light- and heavy-ion particle identification (PID) capability, pulse-height defects, radiation hardness, and emission spectra. The CLARION2 array consists of up to 16 Compton-suppressed HPGe Clover detectors ($\approx4\%$ efficiency at 1 MeV) configured into four rings (eight HPGe crystal rings) using a non-Archimedean geometry that suppresses back-to-back coincident 511-keV gamma rays. The entire array is instrumented with 100- and 500-MHz (14 bit) waveform digitizers which enable triggerless operation, pulse-shape discrimination, fast timing, and pileup correction. Finally, two examples of experimental data taken during the commissioning of the CLARION2-TRINITY system are given: a PID spectrum from $^{16}$O + $^{18}$O fusion-evaporation, and PID and Doppler-corrected $\gamma$-ray spectra from $^{48}$Ti + $^{12}$C Coulomb excitation., Comment: 14 pages, 21 figures

Absolute cross sections for the addition of $s$- and $d$-wave neutrons to $^{14}$C and $^{14}$N have been determined simultaneously via the ($d$,$p$) reaction at 10 MeV/u. The difference between the neutron and proton separation energies, $\Delta S$, is around $-20$ MeV for the $^{14}$C$+$$n$ system and $+8$ MeV for $^{14}$N$+$$n$. The population of the $1s_{1/2}$ and $0d_{5/2}$ orbitals for both systems is reduced by a factor of approximately 0.5 compared to the independent single-particle model, or about 0.6 when compared to the shell model. This finding strongly contrasts with results deduced from intermediate-energy knockout reactions between similar nuclei on targets of $^{9}$Be and $^{12}$C. The simultaneous technique used removes many systematic uncertainties., Comment: 6 pages, 4 figures

In this paper we study rational functions of the form $ R_{n,a,c}(z) = z^n + \dfrac{a}{z^n} + c, $ with $n$ fixed and at least $3$, and hold either $a$ or $c$ fixed while the other varies. We locate some homeomorphic copies of the Mandelbrot set in the $c$-parameter plane for certain ranges of $a$, as well as in the $a$-plane for some $c$-ranges. We use techniques first introduced by Douady and Hubbard, that were applied for the subfamily $R_{n,a,0}$ by Robert Devaney. These techniques involve polynomial-like maps of degree two., Comment: 36 pages, 22 figures; in this version made minor editorial changes and improved some figures

Isomers in $^{66}$Ga, $^{67}$Ge, and $^{69}$Ge were recoil-implanted into ferromagnetic hosts of iron and gadolinium at $\approx 6$~K, and the hyperfine magnetic fields were determined by Time Differential Perturbed Angular Distribution (TDPAD) measurements. The hyperfine field strengths at $\approx 6$~K are compared to the results of previous higher-temperature measurements and the amplitudes of the $R(t)$ functions are compared to empirical expectations. The results show that gadolinium can be a suitable host for high-precision in-beam $g$-factor measurements. The results of new $g$-factor measurements for isomers in $^{66}$Ga and $^{67}$Ge are $g(^{66}$Ga$,7^{-}) = +0.126(4)$, supporting a $[\pi_{f5/2} \otimes \nu g_{9/2}]_{7^-}$ configuration assignment, and $g(^{67}$Ge$,\frac{9}{2}^{+})=-0.1932(22)$, derived from a new measurement of the ratio $g(^{67}\mathrm{Ge})/g(^{69}\mathrm{Ge}) = 0.869(9)$. These values are in agreement with previous results. The $R(t)$ amplitudes indicate that the nuclear alignment produced in the isomeric states was significantly lower than the empirically expected $\sigma/I \approx 0.35$., Comment: 10 pages, 10 figures

The scintillation mechanism in NaI:Tl crystals produces different pulse shapes that are dependent on the incoming particle type. The time distribution of scintillation light from nuclear recoil events decays faster than for electron recoil events and this difference can be categorised using various Pulse Shape Discrimination (PSD) techniques. In this study, we measured nuclear and electron recoils in a NaI:Tl crystal, with electron equivalent energies between 2 and 40 keV. We report on a new PSD approach, based on an event-type likelihood; this outperforms the charge-weighted mean-time, which is the conventional metric for PSD in NaI:Tl. Furthermore, we show that a linear combination of the two methods improves the discrimination power at these energies., Comment: 12 pages, 12 figures, 1 table

The electric monopole ($E0$) transition strength $\rho^2$ for the transition connecting the third 0$^+$ level, a "superdeformed" band head, to the "spherical" 0$^+$ ground state in doubly magic $^{40}$Ca has been determined via $e^+e^-$ pair-conversion spectroscopy. The measured value, $\rho^2(E0; 0^+_3 \to 0^+_1)~=~2.3(5)\times10^{-3}$, is the smallest $\rho^2(E0; 0^+ \to 0^+)$ found in $A<50$ nuclei. In contrast, the $E0$ transition strength to the ground state observed from the second 0$^+$ state, a band head of "normal" deformation, is an order of magnitude larger, $\rho^2(E0; 0^+_2 \to 0^+_1)~=~25.9(16)\times~10^{-3}$, which shows significant mixing between these two states. Large-Scale Shell Model (LSSM) calculations were performed to understand the microscopic structure of the excited states, and the configuration mixing between them; experimental $\rho^2$ values in $^{40}$Ca and neighboring isotopes were well reproduced by the LSSM calculations. The unusually small $\rho^2(E0; 0^+_3 \to 0^+_1)$ value is due to destructive interference in the mixing of shape-coexisting structures, which are based on several different multiparticle-multihole excitations. This observation goes beyond the usual treatment of $E0$ strengths, where two-state shape mixing cannot result in destructive interference.

Non-yrast, excited states in neutron-rich $^{186}$W were populated via inelastic-scattering reactions using beams of $^{136}$Xe nuclei accelerated to 725 and 800 MeV. Levels populated in the reactions were investigated via particle-$ \gamma $ coincidence techniques using the Gammasphere array of High-Purity Germanium detectors and the compact heavy-ion counter, CHICO2. The $ K^{\pi} = 2 ^{+} $ ($\gamma$), $ K^{\pi} = 0^{+}$ and $ K^{\pi} = 2^{-} $ (octupole) rotational side bands were extended to spins $ 14\hbar $, $ 12\hbar $, and $ 13\hbar $, respectively. A staggering pattern observed in the energies of levels in the $ K^{\pi} = 2^{+} $ band was found to be consistent with a potential that gets softer to vibration in the $ \gamma $ degree of freedom with increasing spin. The odd-even staggering of states in the $ K^{\pi} = 2^{-}$ band was found to exhibit a phase opposite to that seen in the $ \gamma $ band; an effect most probably associated with Coriolis coupling to other, unobserved octupole vibrational bands in $^{186}$W., Comment: 14 pages, 16 figures

We demonstrate the first planar Airy light-sheet microscope. Fluorescence light-sheet microscopy has become the method of choice to study large biological samples with cellular or sub-cellular resolution. The propagation-invariant Airy beam enables a ten-fold increase in field-of-view with single-photon excitation; however, the characteristic asymmetry of the light-sheet limits its potential for multi-photon excitation. Here we show how a planar light-sheet can be formed from the curved propagation-invariant Airy beam. The resulting symmetric light sheet excites two-photon fluorescence uniformly across an extended field-of-view without the need for deconvolution. We demonstrate the method for rapid two-photon imaging of large volumes of neuronal tissue., Comment: 7 pages, 4 figures