bluuebunny/crossref_metadata_2025 huggingface dataset:
Applicability of the Blue Wave to the Canal from Villiers to Beaulieu
Authors: Deplaix J. M.
Published: February 2023

The Blue Wave is a locking structure that allows simultaneous navigation in both directions of navigation, without stopping in most cases, and at a speed depending on the local topography.

Its principle has been described in an issue of PIANC Bulletin, N°108, september 2001.

It could be used, in lieu of a set of locks, on a Canal which is presently being improved to CEMT Class Va, far upstream from Paris, the Canal from Villiers to Beaulieu (Petite Seine, France).

It is possible to form 10 reaches of 1,000 m each, separated by doors (mitre or valve). The depth available in the existing borrow pits is sufficient for the navigation of the project boats, which have 31.9 m2 of wetted section.

By using the existing pits, which were dug in advance for improvement of this waterway, the structure very faithfully respects the current levels of these bodies of water, which avoids costly measures to restore the water table. In addition, the 2 upstream gates being non-overtopping, the non-overtopping dykes only total 2 km, instead of 16 km in the lock option.

These two points confirm that the proposed solution is more respectful of the environment and landscapes than the lock option. Thus, since the set speed of the concept is practically the optimum speed permitted by the cross-section of the canal, it can be said that the site of the Canal from Villiers to Beaulieu is optimal for the application of the Blue Wave principle.
Comparative Study of the Hydraulic Characteristics of Stratified Energy Dissipators in In-Chamber Longitudinal Culvert Systems
Authors: Ma Xin , Hu Yaan , Li Zhonghua
Published: February 2023

The study of energy dissipation characteristics of stratified energy dissipators in the lock chamber is carried out by numerical simulation. Discussed the hydraulic characteristics of different energy dissipators in the lock chamber and open channel area (e.g., flow field in the lock chamber, flow distribution in the branch holes and energy dissipation mechanism). The results show that the stratified energy dissipation makes the water flow in the open ditch area more fully mixed; the flow distribution in the branch holes is more balanced; the maximum flow velocity into the bottom of the lock chamber is reduced. The in-chamber longitudinal culvert system with open channel + cover has the best flow conditions, followed by open channel + grating, both of the above are better than the traditional open ditch energy dissipator.
Inland Navigation, a Priority for PIANC/InCom
Authors: Rigo Philippe
Published: February 2023

This keynote paper presents the PIANC Inland Navigation Commission (INCOM; http://incomnews.org/). INCOM is one of the 4 technical commissions of PIANC, which is targeting to Inland Navigation, and particularly to the waterway infrastructure and management.
Corridor Scale Planning of Bunker Infrastructure for Zero-Emission Energy Sources in Inland Waterway Transport
Authors: Jiang Man , Baart Fedor , Visser Klaas , Hekkenberg Robert , Van Koningsveld Mark
Published: February 2023

The availability of supporting bunker infrastructure for zero-emission energy sources will be key to accommodate zero-emission inland waterway transport (IWT). However, it remains unclear which (mix of) zero-emission energy sources to prepare for, and how to plan the bunker infrastructure in relative positions and required capacity at corridor scale. To provide insight into the positioning and dimensions of bunkering infrastructure we propose a bottom-up energy consumption method combined with agent based network simulation. In the method, we first produce a two-way traffic energy consumption map, aggregated from the energy footprint of individual vessels on the transport network. Next we investigate the potential sailing range of the vessels on the network if they would sail the same routes, but with alternative energy carriers. Based on the sailing range of the vessels for different energy carriers, the maximum inter-distance between refuelling points can be estimated. By aggregating the energy consumptions of all the vessels on the network, we can estimate the required capacity of a given refuelling point. To demonstrate the basic functionality we implement the method to four representative corridor scale inland shipping examples using zero-emission energy sources including hydrogen, batteries, e-NH3, e-methanol and e-LNG. The application in this paper is limited to four abstract cases. A recommended next step is to apply this approach to a more realistic network.
Design of Longitudinal Air Bubbler System Inside Ship Lock
Authors: Biln Iqbal Singh , Engel Chandler
Published: February 2023

This study investigated the expected behavior of installing a longitudinal air bubbler system in the St Lambert Lock, Quebec, Canada to bring “warm” water from the depths of the lock chamber and reduce ice buildup on the lock walls during the winter navigation. The bubbler manifold would be installed near the bottom of the lock chamber and extend along the entire wall of the lock chamber. Compressed air would be provided to the manifold and the air would be released through a series of holes (orifices) installed along the length of the manifold. A vertical water current would be induced in the lock chamber by the rising air bubbles. The continuous supply of water to the surface should reduce ice formation along the wall of the chamber. This use of a longitudinal air bubbler system to reduce ice buildup along lock walls during the winter season is a novel use of an air bubbler system in North America in a navigation lock.
Evolution of Undular Surges in a Navigation Channel
Authors: Zheng Feidong , Li Xueyi , Zhang Fan , Mu Ping
Published: February 2023

An undular surge is a secondary wave characterized by free-surface undulations over the body of a positive wave. The formation of undular surges is strongly linked to the departure of pressure distribution from hydrostatic due to the combined effects of wave nonlinearity and dispersion. In navigation channels, undular surges may be generated by the filling or emptying operation of lock chambers. The propagation of undular surges is associated with the periodic flow variations, and therewith they can cause impulse motion responses of navigation ships and even navigation accidents in some instances. In the present study, the free-surface and hydrodynamic properties of undular surges induced by the emptying operation of lock chambers were experimentally investigated. Detailed free-surface and velocity measurements were performed with a series of capacitance wave gauges and an acoustic Doppler velocimeter in a horizontal rectangular water wave channel. Both nonbreaking and breaking surges were recognized and analyzed. The results demonstrated that the wave face of a nonbreaking undular surge could be accurately described by solitary wave theory. However, the velocity distributions beneath the surge deviated significantly from the solitary wave solution. Based on the experimental results, a formula relating the longitudinal velocity component to free-surface elevation was established. Overall, this study provided new insights into the analogy of an undular surge and a solitary wave.
Experimental Investigation of Hydrodynamics on Abrupt-Expansion Pipe Behind Control Valve of Hydro-Driven Shiplift
Authors: Wang Jiao , Hu Yaan
Published: February 2023

Control valve is the special core equipment of hydro-driven ship lift, it is similar to the electric motor of the electric driven ship lift, which is the key to the safe and efficient operation of ship lift. Hydro-driven ship lift requires very high performance of control valve. It not only needs to control the flow accurately, but also to meet the needs of large flow. It is difficult to avoid cavitation for control valve to work under high pressure difference. How to control the erosion and destruction of valves and pipelines caused by cavitation is related to the operation safety and efficiency of hydro-driven ship lift. Sudden expansion of pipe behind the valve is a simple and efficient valve cavitation suppression technology. Aiming at typical control valve (plunger valve), this paper uses physical model tests and theoretical analysis to study the effect of sudden expansion of pipe behind the valve on the flow resistance characteristics of valves, and comprehensively consider the effects of valve type, flow pattern, and flow pulsation. According to the analysis, the relationship between sudden expansion ratio of the pipe and valve flow coefficient is obtained, and the test results are in good agreement with the theoretical analysis. Based on the theoretical analysis and considered the effect of cavitation defense, the expansion ratio for this type of abrupt expansion pipe is suggested to be 3.00. This study has guiding significance for the anti-cavitation technology of industrial valves, and can be used as a reference for the design of pipelines for water delivery and pressure regulation projects.
Improvement Measures of Navigable Flow Conditions in the Baihutan Hydro-Junction in Changshanjiang River, China
Authors: Wang Rongrong , Sun Aiping , Zhang Shouyuan , Cheng Hongyu , Zhao Gensheng
Published: February 2023

The Baihutan hydro-junction of Changshanjiang River is located in the straight section of S-shaped channel, and the upstream approach channel is located in the concave bank of the bendy section of river. Navigable flow conditions in the entrance area of upstream and the bend connection area are complicated and disordered under the influence of circumfluence. Ships are prone to drift due to the high-speed transverse flow, which makes it difficult to meet the requirements of safe navigation. In the present study, the navigable flow conditions were evaluated by building a 1:80 hydraulic model and the remote-control ship model test were carried out. Besides, flow conditions in the entrance area, the approach channel and the bend connection area were investigated, and optimization and improvement measures were also proposed. Researches indicated that, affected by the water flow at the top of the bend and the narrowed river channel, the transverse and longitudinal flow velocity in the entrance area and the bend connection area were faster. Adjusting the layout of channel to reduce the angle between the mainstream and the axis of the channel, and expanding the cross-sectional area of the approach channel could effectively improve the navigable flow conditions and ensure the navigation safety. The results of this study can provide references for similar rivers.
Live Digital Twin for Hydraulic Structures Fatigue Estimation
Authors: Condemine Cyril , Grau Loic , Masson Yves , Aubry Sebastien
Published: February 2023

Maintaining hydraulic structures such as dams, penstocks, or water lock gates in operating conditions and optimizing their maintenance costs are key issues for energy production or river navigation. The ultimate objective is to know the real state of fatigue and damage of the structure and identify any related anomalies. In this paper, we introduce a digital twin, for fatigue evaluation merging measured data obtained with an embedded sensor network and a 3D numerical model that converts in real time measured data into fatigue. After 3 years of R&D collaboration between CNR and Morphosense in the maintenance of navigation lock gates or dam gates, this presentation exposes how the proposed Live Digital Twin solution contributes to fatigue evaluation and more generally to global structural monitoring in dealing with fundamental issues of hydraulic structures: risk assessment, maintenance in operating conditions and maintenance costs optimization. After a context and state of the art introduction, the second part will detail the system overview. In the third part, the monitoring system will be addressed.
Optimizing Upstream Approach Wall to Navigation Lock in Narrow Rivers
Authors: Bousmar Didier , Swartenbroekx Catherine , Pierard Geoffrey , Van Hees Emmanuel
Published: February 2023

In canalized rivers, navigation locks are often located aside a weir. River currents are concentrated towards the weir. As a result, vessels face transverse currents and significant outdraft forces when approaching the lock. An approach wall can be designed to isolate the final lock approach from the weir flow. This wall can be a plain wall, or a perforated wall. Depending on the design of the wall openings, the flow velocity gradient and the outdraft forces are translated upstream at the entrance of the port. At this location, the vessel keeps a larger velocity and can manoeuvre more easily. An optimal design of the opening should minimize the transverse forces acting on the vessel. Guidelines for the design of such approach walls may be found in the literature but cover only large and very large rivers. The present contribution focuses on narrower rivers, with a low ratio between port entrance width and river width.
Construction of Cai Mep International Container Terminal
Authors: Suzuki Koji , Sumita Yoshinori
Published: February 2023

Cai Mep International Container Terminal was constructed 80 km southeast of Ho Chi Minh city, Vietnam, where a thick and soft clay deposit was widely found from the top of the ground. To minimize consolidation settlement after construction, soil improvement by PVD was extensively applied. Sand filling including preload up to +11.8 mCD was required on the existing ground of +3.5 mCD. Stability of this sand filling on river side was the first concern in the construction work. According to soil investigation to study shear strength profile of the soft clay, original design of sand filling was revised to maintain stability of the filling on river side. This report presents the original and the revised design, as well as the results of soil investigation.
Research on Influence from Ship Navigating in the Intermediate Channel Between Ship Lifts on Hydraulic Characteristics
Authors: Chen Yingying , Hu Yaan , Li Zhonghua
Published: February 2023

Through the method of physical model test, tests of ship navigating in the intermediate channel of the navigation structure of Longtan Hydropower Station were carried out to study the hydraulic characteristics, such as the water surface fluctuation in the ship chamber and the intermediate channel, the heave of ship bow and stern, and the mooring force of the berthing ship under different navigational conditions. The results indicate that from the perspective of ship lift operational efficiency, docking safety, ship navigating safety and berthing safety, the design navigable water depth of 3.6 m in the intermediate channel is reasonable and the navigational speed of the ship in the intermediate channel should not exceed 1.5 m/s. The research results can provide scientific basis and technical reference for the design and operation of the navigation structure of Longtan Hydropower Station.
Ship Impact for Suederelbe Bridge Crossing in Hamburg
Authors: Kunz Claus , Schülke Jan
Published: February 2023

In the harbour of Hamburg a new bridge crossing the Suederelbe at Elbe km 620 has been planned. The bridge is part of the BAB26 motorway. Contracted by DEGES, a German company for highway planning and design, BAW determined the ship impact loads on the basis and methodology of EN 1991-1-7 (2006) on a site - specific basis, BAW (2016). The Suederelbe Bridge crossing will have a length of 695,60 m with main span bridging the fairway over 350 m. The pylon height of the main piers is planned to be 150 m. The clearance height of the Suederelbe crossing should be 53 m above sea level. The two pylons and main piers of the Suederelbe bridge crossing, which are to be positioned close to the bank, are at risk of ship impact. About 6,000 seagoing vessels up to 33,000 dwt are passing the future bridge. Fleet structure, ship passages, speeds, accident rates and nautical conditions were analysed and ship impact loads for the piers and protective structures were determined using a load model on one hand and a collision model on the other hand. Load and collision model are probabilistic and based on corresponding distributions of the decisive influencing parameters, whereby this approach represents state-of-the-art technology. Based on the collision model, the average time that the eastern pylon is being impacted is expected to be 470 years, while the average time for the western pylon is expected to be 1,240 years.

The impact loads for the east pylon are dynamic loads with FFdyn  =  17.5 MN for frontal impact and FLdyn  =  4.0 MN for lateral impact. Out of the models the impact load can be determined as dependent on the distance of the piers (pylons) to the fairway center line. The variation of the span distance of the pylons show the plausibility of the developed and used modelling.
Continuous Management of the Channel Design to Optimize Navigability in the Middle Paraná River Waterway: “Santa Fe – Confluence”. Argentina
Authors: Marpegan M. L. , Temer L. A.
Published: February 2023

This paper exposes how HIDROVIA S.A. (Inland Waterway Concession company) worked in the Middle Paraná River inland waterway “Santa Fe – Confluence” to maintain the navigation channel without dredging works by means of four steps: frequent bathymetric surveys, study of AIS vessels tracks, a special coordination of logistic works in the river with the technical team and buoy tenders crew and effective communication plans with involved stakeholders. This is a stretch of the well-known Paraguay – Paraná Inland Waterway in South America that reaches deep waters in the Río de la Plata. Physical characteristics and depths along this section of Paraná River determine what kind of vessels can sail according to its draught up to 10 ft. With 2 ft. For under keel clearance. From October 2010 to September 2021, dredging works and installation and maintenance of modern aids to navigation system were granted by the concession company. Given the intense morphological dynamics and thalweg migration of the river in this section, the contract stated that it was no suitable to keep a fixed channel design by means of permanent dredging works. It established that dredging works should only be done when and where it is not possible to maintain the channel design by readjustment of its profile with partial changes in the trace and direction of the waterway axis. The Aids to Navigation Department of HIDROVIA S:A. succeeded in doing that by implementing the continuous management of the channel design to optimize sustainable navigation in the Santa Fe – Confluence waterway.
Application and Prospect of Spatial Information Technology in Inland Waterway Resources Census
Authors: Jia Pengpeng , Jin Zhefei , Feng Honglin , Yang Qiong , Yang Wenwu
Published: February 2023

In recent years, the rapid development of GIS, remote sensing, big data and other spatial information technologies have provided a huge driving force for the information construction and development of many industries. As an important branch of transportation field, inland water transportation also has great development opportunities in information construction. Since the second National Inland Waterway Census, great changes have taken place in the current situation of China’s inland waterway. It is urgent to carry out a new round of National Inland Waterway Census and comprehensively find out the current situation of China’s inland waterway. This paper comprehensively discusses the current situation of the application of spatial information technology in the general census of resources in typical industries. This paper also summarizes the basic situation of Inland Waterway Census in China, and analyzes the key and difficult points of the application of spatial information technology in Waterway Census data acquisition, working base map compilation, application achievement display and so on. It initially puts forward the technical scheme of channel resources census based on information means and online system. Compared with the traditional offline census, the technical scheme proposed in this study has achieved a breakthrough in improving the efficiency of census and ensuring the quality of census results. The research can provide technical reserves and experience for the general survey of channel resources for the whole country and all the provinces.
Field Measurements of Flow Velocities in Propeller Jets
Authors: Cantoni Irene , Van Der Hout Arne , Houwing Erik Jan , Roubos Alfred , Ruijter Michel
Published: February 2023

Propellers of ships generate high velocities adjacent to quay walls, jetties and locks. Generally, a bottom protection is installed in order to prevent instability due to scour. Although design guidance exist, propeller-induced loads are far from fully understood and have predominantly been derived on the basis of model tests. The validation of the existing design methods is lacking, especially for specific types of bow thrusters. In this research, field measurements of flow velocities induced by a 4-channel bow thruster system against a vertical quay wall have been performed. Test results showed a flow characterized by low mean velocities and large fluctuations, with the extent of reflected flow limited to few meters from the quay wall and inflow beneath the suction points playing a role.
Smart Shipping on Inland Waterways
Authors: Pauwelyn Ann-Sofie , Turf Sim
Published: February 2023

Inland shipping has been struggling with a shortage of skippers for several years. This means, among other things, that smaller vessels disappear and the smaller waterways are no longer used. In addition, it is also difficult for inland shipping to compete with road transport. In time, this will cause a reverse modal shift: cargo will be brought back from the waterway to the road. However, the road is already dealing with a lot of congestion while the potential of the waterway is being used less and less. This will lead to major mobility problems.

Over the years, an international consensus has grown that the automation of vessels can be a mean to solve a large part of the above problems and to revive transport via the waterways. In this way, the great pressure on our roads will also be reduced.

In order to gain a better insight in the possibilities of Smart Shipping, the PIANC WG 210 was established in 2019. The PIANC INCOM WG 210 Report on Smart Shipping on Inland Waterways has been published in March 2022. This report researches the impact of Smart Shipping developments on the physical and digital infrastructure and on traffic management, with focus on inland waterways. Smart shipping developments were viewed from the perspective of infrastructure providers and traffic managers of inland waterways to stimulate and maximize the deployment of Smart Shipping.

The report includes an analysis of the current (until 2019) Smart Shipping developments, what is currently lacking to stimulate Smart Shipping developments, as well as recommendations for the future that can be picked up in other PIANC working groups or research groups. This paper will highlight the findings of the WG and will zoom in on some more concrete examples of Smart Shipping in Belgium, where de Vlaamse Waterweg nv is monitoring a test area in which several 100s of test have taken place since 2019. Recent international legal initiatives will also be described.
Analysis of Erosion and Deposition Characteristics in Hukou-Jiangyin Reach of the Lower Yangtze River After the Operation of the Three Gorges Project
Authors: Cao Shuang , Cheng Long , Wang Nairu , Li Qiang , Luo Hongyu
Published: February 2023

With the operation of the Three Gorges Project (TGP) and the reservoirs in the upper reaches of the Yangtze River, the sediment transport reduced significantly in the lower reaches of the Yangtze River since 2003, leading to great changes in the relationship between flow and sediment. In order to study the variation characteristics of the river channel under new conditions, the variation characteristics of flow and sediment at the main hydrological stations, the amount and intensity of erosion/deposition in the Hukou-Jiangyin reach, and the distribution of erosion/deposition in the channel were analyzed. The results showed that the Hukou-Jiangyin reach experienced both erosion and deposition from 1998 to 2006, while unidirectional erosion in both benchland and channel after 2006. From 2006 to 2020, the average annual erosion intensities per kilometer below bankfull channel in Hukou-Datong reach and Datong-Jiangyin reach were 12.56 × 104 m3/km and 17.17 × 104 m3/km, increasing by 79.94% and 67.35%, respectively, compared with those during the period from 1998 to 2001, i.e., the times before the impoundment of TGP. The riverbed erosion intensity of Datong-Jiangyin reach was 37% higher than that of the upper Hukou-Datong reach. The erosion mainly occurred below bankfull channel, while the erosion between low water channel and bankfull channel only accounted for 10% – 20%. Specifically, the ratios of the erosion below low water channel and bankfull channel to those below flood channel accounted for 86.67% and 91.14% in Hukou-Datong reach, respectively. And those ratios in Datong-Jiangyin reach were 80.34% and 86.69%, respectively.
Best Practice Approach for Layouting Technical-Biological Bank Protections for Inland Waterways – PIANC WG 128
Authors: Benhard Söhngen , Ma Dianguang ,   Other Members of PIANC INCOM WG 128
Published: February 2023

The worldwide increasing number of national guidelines and growing experience with realized green bank protections (constructions using insofar possible living or at least wooden construction material) in navigable waters, led to install a PIANC INCOM Working Group (WG) to collect and condense expert knowledge in this field of work and prepare it for practitioners for design purposes. The corresponding PIANC report, called “Technical-Biological Bank Protections for Inland Waterways”, is foreseen to be released this year.

The report, whose structure, content, key findings and approach will be highlighted briefly in this contribution to the Smart Rivers Conference, tries to overcome the usual problems in design cases, which need knowledge and experience of civil engineers, eco-engineers and ecologists altogether and the way how the success of bank stabilization measures will be noticed and rated. The WG members had to notice that functionality assessment is not that simple, whereby partly huge differences between those who designed, realized and maintained measures and external parties as well as cultural differences occurred.

To overcome these problems and thus to objectivize the choice and layout of alternative solutions, which may help to convince people responsible for waterway development and maintenance to use green measures instead of traditional bank protections as riprap, a Best Practice Approach was developed, based on a catalogue of numerous realized measures, which are described e.g. in so-called Fact Files. The content of these descriptions, especially the local boundary conditions (BCs shortly in the following) and the balance between aims and achieved functionality issues, was used to assess the possible suitability of a chosen measure under generally different design conditions than those in the described realizations.

This was achieved inter alia by a scoring system, assessing differences between Design- (DC) and Analysis Cases (shortly ACs from the catalogue of measures), which is called Feasibility Check (it answers the question, whether experiences made with the AC-cases can be transferred to the DC) and differences between user-specified aims in the DC and expected performance issues from the ACs, called “Suitability Check” (answers the question, how far expected functionality issues may probably be achievable). This was done both for technical and ecological issues, whereby the scores were chosen and reviewed interdisciplinary and internationally to overcome the aforementioned assessment differences.
The ice cone family and iterated integrals for Calabi-Yau varieties
Authors: Duhr Claude , Klemm Albrecht , Nega Christoph , Tancredi Lorenzo
Published: February 2023

Abstract

We present for the first time fully analytic results for multi-loop equal-mass ice cone graphs in two dimensions. By analysing the leading singularities of these integrals, we find that the maximal cuts in two dimensions can be organised into two copies of the same periods that describe the Calabi-Yau varieties for the equal-mass banana integrals. We obtain a conjectural basis of master integrals at an arbitrary number of loops, and we solve the system of differential equations satisfied by the master integrals in terms of the same class of iterated integrals that have appeared earlier in the context of equal-mass banana integrals. We then go on and show that, when expressed in terms of the canonical coordinate on the moduli space, our results can naturally be written as iterated integrals involving the geometrical invariants of the Calabi-Yau varieties. Our results indicate how the concept of pure functions and transcendental weight can be extended to the case of Calabi-Yau varieties. Finally, we also obtain a novel representation of the periods of the Calabi-Yau varieties in terms of the same class of iterated integrals, and we show that the well-known quadratic relations among the periods reduce to simple shuffle relations among these iterated integrals.
Model selection and signal extraction using Gaussian Process regression
Authors: Gandrakota Abhijith , Lath Amit , Morozov Alexandre V. , Murthy Sindhu
Published: February 2023

Abstract

We present a novel computational approach for extracting localized signals from smooth background distributions. We focus on datasets that can be naturally presented as binned integer counts, demonstrating our procedure on the CERN open dataset with the Higgs boson signature, from the ATLAS collaboration at the Large Hadron Collider. Our approach is based on Gaussian Process (GP) regression — a powerful and flexible machine learning technique which has allowed us to model the background without specifying its functional form explicitly and separately measure the background and signal contributions in a robust and reproducible manner. Unlike functional fits, our GP-regression-based approach does not need to be constantly updated as more data becomes available. We discuss how to select the GP kernel type, considering trade-offs between kernel complexity and its ability to capture the features of the background distribution. We show that our GP framework can be used to detect the Higgs boson resonance in the data with more statistical significance than a polynomial fit specifically tailored to the dataset. Finally, we use Markov Chain Monte Carlo (MCMC) sampling to confirm the statistical significance of the extracted Higgs signature.
Gravitational Coleman-Weinberg mechanism
Authors: Álvarez-Luna Clara , de la Calle-Leal Sergio , Cembranos José A. R. , Sanz-Cillero Juan José
Published: February 2023

Abstract

The Coleman-Weinberg mechanism provides a procedure by which a scalar field, which initially has no mass parameters, acquires a mass due to the anomalous nature of scale symmetry. Loop corrections trigger a spontaneous symmetry breaking and the appearance of a non-trivial vacuum. We first review the basic example of the Coleman-Weinberg mechanism, scalar Quantum Electrodynamics, in a perturbative regime where the scalar particle becomes massive through photon loops. We then present the main results of this article, what we name the gravitational Coleman-Weinberg mechanism: we analyse the same effect in a gravitational theory without explicit energy scales at tree-level. Finally, we also study the mechanism for two scalar fields in the mentioned gravitational theory. We will derive the gravitational Coleman-Weinberg potentials, analyse the parameter space where we have a symmetry breaking, and obtain the value of the corresponding scalar masses.
Sturm–Liouville Differential Inclusions with Set-Valued Reaction Term Depending on a Parameter
Authors: Cardinali Tiziana , Continelli Elisa
Published: February 2023

In this paper we study the controllability for a Cauchy problem governed by a nonlinear differential inclusion driven by a Sturm–Liouville type operator. In particular, the considered second order differential inclusion involves a set-valued reaction term depending on a parameter. The key tool in the proof of the controllability result we provide is a multivalued version of the theorem recently proved by Haddad–Yarou, here established for an initial conditions problem monitored by a nonlinear second order differential inclusion presenting the sum of two multimaps on the right-hand side. We thereby deduce the existence of a local admissible pair for the considered control problem, that is the existence of a couple of functions consisting of a control, which is a measurable function, and the correspondent trajectory, which is an absolutely continuous function with absolutely continuous derivative. Secondly, under appropriate assumptions on the involved multimaps, we obtain an increased regularity for the solutions produced by our existence result. This regularity is the same of that recently tested by Bonanno, Iannizzotto and Marras for a different type of problem, which however involves the Sturm–Liouville operator.
A Non-aligning Variant of Generalized Turán Problems
Authors: Gerbner Dániel
Published: February 2023

In the so-called generalized Turán problems we study the largest number of copies of H in an n-vertex F-free graph G. Here we introduce a variant, where F is not forbidden, but we restrict how copies of H and F can be placed in G. More precisely, given an integer n and graphs H and F, what is the largest number of copies of H in an n-vertex graph such that the vertex set of that copy does not contain and is not contained in the vertex set of a copy of F? We solve this problem for some instances, give bounds in other instances, and we use our results to determine the generalized Turán number for some pairs of graphs.
Equivalence of weak and viscosity solutions for the nonhomogeneous double phase equation
Authors: Fang Yuzhou , Rădulescu Vicenţiu D. , Zhang Chao
Published: February 2023

We establish the equivalence between weak and viscosity solutions to the nonhomogeneous double phase equation with lower-order term $$\begin{aligned} -{\text {div}}(|Du|^{p-2}Du+a(x)|Du|^{q-2}Du)=f(x,u,Du),\quad 1<p\le q<\infty ,\ a(x)\ge 0. \end{aligned}$$

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Macroscopic Loops in the Bose Gas, Spin O(N) and Related Models
Authors: Quitmann Alexandra , Taggi Lorenzo
Published: February 2023

We consider a general system of interacting random loops which includes several models of interest, such as theSpin O(N) model,random lattice permutations, a version of theinteracting Bose gasin discrete space and of theloop O(N) model.We consider the system in$${\mathbb {Z}}^d$$Zd,$$d \ge 3$$d≥3, and prove the occurrence of macroscopic loops whose length is proportional to the volume of the system. More precisely, we approximate$${\mathbb {Z}}^d$$Zdby finite boxes and, given any two vertices whose distance is proportional to the diameter of the box, we prove that the probability of observing a loop visiting both is uniformly positive. Our results hold under general assumptions on the interaction potential, which may have bounded or unbounded support or introduce hard-core constraints.
Nearly Periodic Maps and Geometric Integration of Noncanonical Hamiltonian Systems
Authors: Burby J. W. , Hirvijoki E. , Leok M.
Published: February 2023

M. Kruskal showed that each continuous-time nearly periodic dynamical system admits a formalU(1)-symmetry, generated by the so-called roto-rate. When the nearly periodic system is also Hamiltonian, Noether’s theorem implies the existence of a corresponding adiabatic invariant. We develop a discrete-time analog of Kruskal’s theory. Nearly periodic maps are defined as parameter-dependent diffeomorphisms that limit to rotations along aU(1)-action. When the limiting rotation is non-resonant, these maps admit formalU(1)-symmetries to all orders in perturbation theory. For Hamiltonian nearly periodic maps on exact presymplectic manifolds, we prove that the formalU(1)-symmetry gives rise to a discrete-time adiabatic invariant using a discrete-time extension of Noether’s theorem. When the unperturbedU(1)-orbits are contractible, we also find a discrete-time adiabatic invariant for mappings that are merely presymplectic, rather than Hamiltonian. As an application of the theory, we use it to develop a novel technique for geometric integration of non-canonical Hamiltonian systems on exact symplectic manifolds.
Evidence of earthquake seasonality in the Azores Triple Junction
Authors: Lordi Ana L. , Neves Maria C. , Custódio Susana , Dumont Stéphanie
Published: February 2023

This work presents evidence of seasonal and inter-annual variations of the earthquake occurrence rate in the Azores Triple Junction, on the Mid-Atlantic Ridge (MAR). Annual cycles in microearthquakes are relatively common in intraplate continental regions affected by large hydrological loads, but this is the first time that earthquake seasonality is recognized near mid-ocean ridges. First, we benchmark the methodology by matching the published results of earthquake seasonality in the intraplate New Madrid Seismic Zone (USA). Next, we analyze the Azores earthquake catalogue, from 2008 to 2018, separately for oceanic and island regions. The results demonstrate that the seasonal modulation of the seismicity rate is only observed in the ocean, especially in the vicinity of the triple junction, with more earthquakes occurring during the summer months from May to August. Monte Carlo simulations show that the probability of observing such seasonality by chance is less than 1% for the magnitude band from 3.3 to 4.5, well above the detection threshold and magnitude of completeness of the seismic catalogue. The methodology includes a Jack-Knife approach, which shows that the oceanic seasonality is not the consequence of abnormal or extreme events. Although we speculate about possible earthquake triggering processes, it remains a challenge to definitely establish the mechanism responsible for the observed earthquake seasonal modulation in the Azores.
Different choline supplement metabolism in adults using deuterium labelling
Authors: Böckmann Katrin A. , Franz Axel R. , Shunova Anna , Minarski Michaela , Wiechers Cornelia , Poets Christian F. , Bernhard Wolfgang
Published: February 2023

Background

Choline deficiency leads to pathologies particularly of the liver, brain and lung. Adequate supply is important for preterm infants and patients with cystic fibrosis. We analysed the assimilation of four different enterally administered deuterium-labelled (D9-) choline supplements in adults.

Methods

Prospective randomised cross-over study (11/2020–1/2022) in six healthy men, receiving four single doses of 2.7 mg/kg D9-choline equivalent each in the form of D9-choline chloride, D9-phosphorylcholine, D9-alpha-glycerophosphocholine (D9-GPC) or D9-1-palmitoyl-2-oleoyl-glycero-3-phosphoryl-choline (D9-POPC), in randomised order 6 weeks apart. Plasma was obtained at baseline (t = − 0.1 h) and at 0.5 h to 7d after intake. Concentrations of D9-choline and its D9-labelled metabolites were analysed by tandem mass spectrometry. Results are shown as median and interquartile range.

Results

Maximum D9-choline and D9-betaine concentrations were reached latest after D9-POPC administration versus other components. D9-POPC and D9-phosphorylcholine resulted in lower D9-trimethylamine (D9-TMAO) formation. The AUCs (0-7d) of plasma D9-PC concentration showed highest values after administration of D9-POPC. D9-POPC appeared in plasma after fatty acid remodelling, predominantly as D9-1-palmitoyl-2-linoleyl-PC (D9-PLPC), confirming cleavage to 1-palmitoyl-lyso-D9-PC and re-acylation with linoleic acid as the most prominent alimentary unsaturated fatty acid.

Conclusion

There was a delayed increase in plasma D9-choline and D9-betaine after D9-POPC administration, with no differences in AUC over time. D9-POPC resulted in a higher AUC of D9-PC and virtually absent D9-TMAO levels. D9-POPC is remodelled according to enterocytic fatty acid availability. D9-POPC seems best suited as choline supplement to increase plasma PC concentrations, with PC as a carrier of choline and targeted fatty acid supply as required by organs. This study was registered at Deutsches Register Klinischer Studien (DRKS) (German Register for Clinical Studies), DRKS00020498, 22.01.2020.

Study registration

This study was registered at Deutsches Register Klinischer Studien (DRKS) (German Register for Clinical Studies), DRKS00020498.
Psoas abscess in pregnancy: a review of the literature and suggestion of minimally invasive treatment options
Authors: Schröder Carolin , Calite Elina , Böckenhoff Paul , Büttner Thomas , Stein Johannes , Gembruch Ulrich , Strizek Brigitte
Published: February 2023

Aim

Less than a dozen cases of psoas abscesses in pregnancy have been described in the literature. We reviewed the literature when treating a patient with a psoas abscess after ipsilateral double J-ureteral stent placement (in the following: “double J-stent”) due to infected hydronephrosis.

Methods

In January 2022, this review was searched using the Pubmed/MEDLINE database and the mesh terms “Psoas Abscess” AND “Pregnancy”. Studies were included in any language and of all years, describing a psoas abscess during pregnancy. When patients did not have a psoas abscess, the abscess occurred after pregnancy, or when there was no full text available, the article was excluded.

Main results

Ten case reports about patients with psoas abscesses during pregnancy were included. The classical symptomatic triad of psoas muscle abscess included lower back pain, limping and persistent fever with daily spikes. However, in most cases, not all three symptoms can be found. Especially, fever is absent in more than half of the patients. Psoas abscesses are described between 13 and 39 weeks of gestation. Primary psoas abscesses with haematogenous spread are more common during pregnancy than secondary with spread per continuitatem. In the literature, the main reasons for psoas abscess are spinal tuberculosis, drug abuse or underlying diseases such as Crohn’s disease. It is not uncommon for the definite cause to be unclear. Regarding the patient's symptoms, pyelonephritis is often considered a possible aetiology. In general, the main treatment options include antibiotic treatment and abscess drainage. There is no higher caesarean section rate, and no negative outcome for the foetus has been described.

Case presentation

In our patient, a 38-year-old obese Caucasian woman, who had received a left double J-stent for infected hydronephrosis at 15 weeks of gestation, we successfully treated a psoas abscess of 20 × 10 cm with a sonographically assisted abscess drainage and antibiotics. The further course of pregnancy and the elective repeat caesarean section at 38 + 0 weeks of gestation were without any problems. Double J-stent placement and laser stone lithotripsy during puerperium were performed because of recurrent urolithiasis.

Conclusions

Although rare, psoas abscesses can occur during pregnancy, and it has often been treated surgically in the past. A psoas abscess as a complication after infected hydronephrosis and intervention during pregnancy has never been reported in the literature. Even for obese patients, minimally invasive therapy may be a treatment option that has rarely been reported in the literature.
Comparing structural models of linear elastic responses to bending in inosculated joints
Authors: Middleton Wilfrid , Erdal Halil Ibrahim , Detter Andreas , D’Acunto Pierluigi , Ludwig Ferdinand
Published: February 2023

Key message

Mechanical models of inosculations benefit from moderate geometric detail and characterisation of the structurally optimised area of interwoven tension-resistant fibres between the branches.

Living architecture is formed by shaping and merging trees, often in combination with non-living technical elements. These structures often employ the mechanical and physiological adaptations of living trees to support structural loads. Designed and vernacular buildings utilise inosculations to redistribute forces, redirect growth, and provide redundancy. Mechanical models of inosculations in living architecture must be built according to the adaptations available to the tree. Here, mass allocation and fibre orientation are examined. Under typical gravity loads, a zone at the top of the inosculation is subject to tension. This is of particular interest because a trade-off in fibre orientation between mechanical and physiological optimisation is necessary. In tree forks, this results in specifically adapted interwoven fibres. In this study, Finite Element Analysis (FEA) is used to develop different mechanical models to fit bending experiments of four Salix alba inosculations, comparing the models’ accuracy in replicating rotations in the joint. Nine models were developed. Three levels of detail of mass allocation are considered for global isotropic (3 models) and orthotropic (3 models) mechanical properties as well as a model including the interwoven tension zone, a model of local branch and trunk orthotropy, and a model combining these two localised features. Results show significant accuracy gains come from moderate geometric accuracy and consideration of the tension-zone optimisation. The construction of the tension zone in FEA is simple and applicable to natural and artificially induced inosculations.
Grenzsituationen als Potenzial
Authors: Karis Sonja
Published: February 2023

Der Sezierkurs stellt eine wesentliche Etappe in der medizinischen Ausbildung dar. Psychoemotionale Eindrücke der teilnehmenden Student:innen sowie protektive Faktoren wurden von Studierenden der Karl Landsteiner Universität in Kursprotokollen dokumentiert. Im Rahmen einer qualitativen Inhaltsanalyse wurden deren Inhalte ausgewertet. Über die klinische Anwendbarkeit der Ergebnisse wird anhand von exemplarischen Protokolleinträgen berichtet.
Introduction to the special issue for SPIN 2021
Authors: Laarman Alfons , Sokolova Ana
Published: February 2023

The 27th International Symposium on Model Checking Software, SPIN 2021, was held online, July 12, 2021. The current special issue contains extended versions of three selected works published at the symposium. This short introduction presents these selected papers and the selection process.