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We present two novel matter-wave Sagnac interferometers based on ring-shaped time-averaged adiabatic potentials, where the atoms are put into a superposition of two different spin states and manipulated independently using elliptically polarized rf-fields. In the first interferometer the atoms are accelerated by spin-state-dependent forces and then travel around the ring in a matter-wave guide. In the second one the atoms are fully trapped during the entire interferometric sequence and are moved around the ring in two spin-state-dependent ‘buckets’. Corrections to the ideal Sagnac phase are investigated for both cases. We experimentally demonstrate the key atom-optical elements of the interferometer such as the independent manipulation of two different spin states in the ring-shaped potentials under identical experimental conditions.

This paper presents a simple yet versatile approach to simulate skin incisions and suturing using nonlinear finite element analysis on a fixed structured grid with a spring-based suture model. Incisions and wounds are introduced by element removal and the sutures are discretely modeled by applying linear constraint relations pairwise to groups of nodes. Two numerical examples utilize the closing of an elliptical wound to study the influence of the number of sutures and their location, and two test cases use the Z-plasty transposition flap technique to investigate the versatility of the proposed method and for comparison with state-of-the-art results. The results indicate that the presented method is able to recreate literature results to an acceptable level of accuracy. Further, the method proves versatile due to the ability to freely introduce incisions and wounds onto the fixed grid modeling domain without remeshing. Lastly, the two main advantages of the discrete suture representation are the ability to capture local stress concentrations near the sutures and the full freedom in placing the sutures., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

The aim of the paper is to propose the construction of an index that captures the economic complexity of cities over the globe, as well as to explore whether it is a good predictor for a range of city-level economic outcomes. This index aspires to mitigate data scarcity for cities and to provide policy makers with the tools for monitoring the evolving role of cities in the global economy. Analytically, we implement the economic complexity methodology on data for the ownership, location and economic activities of the world's 3,000 largest firms and their subsidiaries to propose a new indicator that quantifies the network of the largest cities worldwide and the economic activities of their globalized firms. We first show that complex cities are the highly diversified cities that host non-ubiquitous economic activities of firms with global presence. Then, in a sample of EU cities, we show that complex cities tend to be more prosperous, have higher population, and are associated with more jobs, human capital, innovation, technology and transport infrastructure. Last, using OLS methodology and accounting for several other confounders, we show that a higher ECI, at the city level, enhances the resilience of cities to negative economic shocks, i.e., their ability to bounce back after a shock. Specifically, we find that the expected increase of the ratio of employment in 2012 over 2006 is 0.01 (mean: 0.992; standard deviation: 0.081) when the ECI increases by 1 unit (mean: 0.371; standard deviation: 1.094), i.e., a satisfactory pace of recovery, in terms of employment. The ability to diversify in the presence of a shock, the reallocation of factors of production to other sectors and the ability to extract rents associated with those diversified activities, uncovers the mechanics of the ECI index., Competing Interests: The authors have declared that no competing interests exist.

Some of the most sensitive and precise measurements-for example, of inertia 1 , gravity 2 and rotation 3 -are based on matter-wave interferometry with free-falling atomic clouds. To achieve very high sensitivities, the interrogation time has to be very long, and consequently the experimental apparatus needs to be very tall (in some cases reaching ten or even one hundred metres) or the experiments must be performed in microgravity in space 4-7 . Cancelling gravitational acceleration (for example, in atomtronic circuits 8,9 and matter-wave guides 10 ) is expected to result in compact devices with extended interrogation times and therefore increased sensitivity. Here we demonstrate smooth and controllable matter-wave guides by transporting Bose-Einstein condensates (BECs) over macroscopic distances. We use a neutral-atom accelerator ring to bring BECs to very high speeds (16 times their sound velocity) and transport them in a magnetic matter-wave guide for 15 centimetres while fully preserving their internal coherence. The resulting high angular momentum of more than 40,000ħ per atom (where ħ is the reduced Planck constant) gives access to the higher Landau levels of quantum Hall states, and the hypersonic velocities achieved, combined with our ability to control potentials with picokelvin precision, will facilitate the study of superfluidity and give rise to tunnelling and a large range of transport regimes of ultracold atoms 11-13 . Coherent matter-wave guides are expected to enable interaction times of several seconds in highly compact devices and lead to portable guided-atom interferometers for applications such as inertial navigation and gravity mapping.

We demonstrate quantum walks of correlated photons in a two-dimensional network of directly laser written waveguides coupled in a "swiss cross" arrangement. The correlated detection events show high-visibility quantum interference and unique composite behavior: strong correlation and independence of the quantum walkers, between and within the planes of the cross. Violations of a classically defined inequality, for photons injected in the same plane and in orthogonal planes, reveal nonclassical behavior in a nonplanar structure.

Multi-mode interference (MMI) devices fabricated in silicon oxynitride (SiON) with a refractive index contrast of 2.4% provide a highly compact and stable platform for multi-photon non-classical interference. MMI devices can introduce which-path information for photons propagating in the multi-mode section which can result in degradation of this non-classical interference. We theoretically derive the visibility of quantum interference of two photons injected in a MMI device and predict near unity visibility for compact SiON devices. We complement the theoretical results by experimentally demonstrating visibilities of up to 97.7% in 2×2 MMI devices without the requirement of narrow-band photons.

Background and Purpose: Human prostate growth and function are tightly controlled by androgens that are generally thought to exert their effects by regulating gene transcription. However, a rapid, non-genomic steroid action, often involving an elevation of intracellular calcium ([Ca(2+) ]i ), has also been described in a number of cell types. In this study we investigate whether androgens acutely regulate [Ca(2+) ]i in stromal cells derived from the human prostate., Experimental Approach: Human-cultured prostatic stromal cells (HCPSCs) were loaded with the calcium-sensitive fluorophore, fura-2-acetoxymethyl ester (FURA-2AM) (10 μM). Changes in [Ca(2+) ]i in response to the androgens, dihydrotestosterone (DHT) and testosterone, as well as EGF were measured by fluorescence microscopy., Key Results: DHT, but not testosterone (0.03-300 nM), elicited concentration-dependent elevations of [Ca(2+) ]i within 1 min of addition. These responses were blocked by the androgen receptor antagonist, flutamide (10 μM); the sarcoplasmic reticulum ATPase pump inhibitor, thapsigargin (1 μM); the inositol trisphosphate receptor inhibitor, 2-aminoethyldiphenyl borate (50 μM) and the PLC inhibitor, U-73122 (1 μM). Responses were also blocked by the L-type calcium channel blocker, nifedipine (1 μM), and by removal of extracellular calcium. A similar transient elevation of [Ca(2+) ]i was elicited by EGF (100 ng·mL(-1) ). The EGF receptor inhibitor, AG 1478 (30 nM), and the MMP inhibitor, marimastat (100 nM), blocked the DHT-induced elevation of [Ca(2+) ]i ., Conclusions and Implications: These studies show that DHT elicits an androgen receptor-dependent acute elevation of [Ca(2+) ]i in HCPSC, most likely by activating EGF receptor signalling., (© 2013 The British Pharmacological Society.)

Quantum mechanics defines two classes of particles-bosons and fermions-whose exchange statistics fundamentally dictate quantum dynamics. Here we develop a scheme that uses entanglement to directly observe the correlated detection statistics of any number of fermions in any physical process. This approach relies on sending each of the entangled particles through identical copies of the process and by controlling a single phase parameter in the entangled state, the correlated detection statistics can be continuously tuned between bosonic and fermionic statistics. We implement this scheme via two entangled photons shared across the polarisation modes of a single photonic chip to directly mimic the fermion, boson and intermediate behaviour of two-particles undergoing a continuous time quantum walk. The ability to simulate fermions with photons is likely to have applications for verifying boson scattering and for observing particle correlations in analogue simulation using any physical platform that can prepare the entangled state prescribed here.

Quantum walks of correlated particles offer the possibility of studying large-scale quantum interference; simulating biological, chemical, and physical systems; and providing a route to universal quantum computation. We have demonstrated quantum walks of two identical photons in an array of 21 continuously evanescently coupled waveguides in a SiO(x)N(y) chip. We observed quantum correlations, violating a classical limit by 76 standard deviations, and found that the correlations depended critically on the input state of the quantum walk. These results present a powerful approach to achieving quantum walks with correlated particles to encode information in an exponentially larger state space.

Local authorities need updated and reliable data on the quantity and the quality of the waste generated in their area, in order to establish an integrated solid waste management system capable of fulfilling regional and national waste management targets. This paper presents information about the quantity and the characteristics of the municipal solid waste generated in Thessaloniki, which is the second largest city in Greece. It is based on the results of three research programs investigating the evolution of municipal solid waste. The investigations were carried out over the last 20 years at the landfill of Thessaloniki by the same research group using statistically acceptable practices for sampling and hand sorting. The results show a great increase in the incoming quantities during the last years and a significant increase of the per capita generation. There is also a significant change in the composition, demonstrated mainly by a decrease in the organic fraction followed by an increase of packaging materials (paper and plastic).