bluuebunny/crossref_metadata_2025 huggingface dataset:
Orthomolekularmedizin – Melatonin & Co. für erholsamen Schlaf
Authors: Wiater Alfred
Published: February 2023

Erholsamer Schlaf beeinflusst nachhaltig unsere Lebensqualität. Schlafstörungen im Sinne von definierten Erkrankungen führen zu erheblicher Krankheitsbelastung. Deshalb liegt die Frage nahe, ob durch Nahrungsergänzungsmittel das Schlafverhalten optimiert werden kann und ob sie supportiv bei Schlafstörungen eingesetzt werden können. Unter Berücksichtigung der biochemischen Abläufe, die dem Schlaf-Wach-Verhalten zugrunde liegen, sind Tryptophan, Serotonin und Melatonin Schlüsselsubstanzen. Zu berücksichtigen sind auch die verstärkenden Kofaktoren bei Stoffwechselprozessen wie Eisen, Vitamin B6 und Magnesium. Diese kommen in der Orthomolekularmedizin zur Förderung des Schlaf-Wach-Verhaltens zum Einsatz. Bei Hinweisen auf Mangelernährung oder zusätzlichen Nahrungsergänzungsbedarf sind die seitens des Bundesinstituts für Risikobewertung (BfR) für Nahrungsergänzungsmittel zusammengestellten Höchstmengen zu beachten. Beim Vorliegen von Schlafstörungen im Sinne definierter Erkrankungen (wie dem Restless-Legs-Syndrom) sind therapeutische Dosen erforderlich.
Wirksamkeit von Safran beim
Aufmerksamkeitsdefizit-/Hyperaktivitätssyndrom
(ADHS)
Authors: Chrubasik-Hausmann Sigrun
Published: February 2023

Das Aufmerksamkeitsdefizit-/Hyperaktivitätssyndrom (ADHS) mit
einer Prävalenz von 5% ist charakterisiert durch
Aufmerksamkeitsstörungen, Hyperaktivität und
Impulsivität sowie Desorganisation und emotionale Symptome wie schnellen
Stimmungswechsel und verminderte Belastbarkeit bei Stress. Die meisten
ADHS-Betroffenen werden mit Methylphenidat (Ritalin®)
behandelt, obwohl etwa 30% nicht auf das Amphetaminderivat ansprechen
und unerwünschte Wirkungen oft zum Absetzen der Therapie führen.
Die zentrale Breitspektrumwirkung von Safran weist auf einen rationalen Einsatz
von Zubereitungen daraus als Behandlungsoption bei ADHS. Zur Evidenz der
Wirksamkeit liegen derzeit 4 Pilotstudien vor, die zeigen, dass Safran dem
Methylphenidat nicht unterlegen ist und dass eine zusätzliche Gabe von
Safran zum Methylphenidat die Wirksamkeit verstärkt. Weitere Studien
sind erforderlich, um die Wirkgröße von Safran bei ADHS zu
definieren.
Arbutus unedo L., Der (Westliche) Erdbeerbaum
Authors: Latté KlausPeter
Published: February 2023

Arbutus unedo L., der (Westliche) Erdbeerbaum, ist im Mittelmeerraum
weit verbreitet. Die Blätter werden seit der Antike arzneilich
aufgrund ihrer adstringierenden Wirkungen zur Behandlung von Diarrhoe und
als Gurgelmittel verwendet. Zudem ist die traditionelle Verwendung der
Blattdroge als Harnwegsdesinfizienz und als antientzündliches,
antidiabetisches und antihypertensives Agens bekannt. Phytochemische
Untersuchungen führten zur Isolierung von Arbutin und seinen
Derivaten, zu einem breiten Spektrum an phenolischen Substanzen,
u. a. an Gerbstoffen und Flavonoiden, sowie zu Iridoiden und einer
wasserdampfflüchtigen Fraktion. Moderne In-vitro-Untersuchungen
belegen antimikrobielle, antioxidative, antiinflammatorische und
kardiovaskuläre Wirkungen für die Blattdroge. Bisher liegen
noch keine klinischen Studien zur Wirksamkeit der Blattdroge
und/oder zu Zubereitungen daraus vor.
Low von Willebrand Disease: A Bleeding Disorder of Unknown Cause?
Authors: O'Donnell James S. , Baker Ross I.
Published: February 2023

von Willebrand disease (VWD) represents the most common inherited bleeding disorder. The majority of VWD cases are characterized by partial quantitative reductions in plasma von Willebrand factor (VWF) levels. Management of patients with mild to moderate VWF reductions in the range of 30 to 50 IU/dL poses a common clinical challenge. Some of these low VWF patients present with significant bleeding problems. In particular, heavy menstrual bleeding and postpartum hemorrhage can cause significant morbidity. Conversely, however, many individuals with mild plasma VWF:Ag reductions do not have any bleeding sequelae. In contrast to type 1 VWD, most patients with low VWF do not have detectable pathogenic VWF sequence variants, and bleeding phenotype correlates poorly with residual VWF levels. These observations suggest that low VWF is a complex disorder caused by variants in other genes beyond VWF. With respect to low VWF pathobiology, recent studies have shown that reduced VWF biosynthesis within endothelial cells likely plays a key role. However, pathological enhanced VWF clearance from plasma has also been described in approximately 20% of low VWF cases. For low VWF patients who require hemostatic treatment prior to elective procedures, tranexamic acid and desmopressin have both been shown to be efficacious. In this article, we review the current state of the art regarding low VWF. In addition, we consider how low VWF represents an entity that appears to fall between type 1 VWD on the one hand and bleeding disorders of unknown cause on the other.
Immune Plasma for the Treatment of COVID-19: Lessons Learned so far
Authors: Schrezenmeier Hubert , Hoffmann Simone , Hofmann Henrike , Appl Thomas , Jahrsdörfer Bernd , Seifried Erhard , Körper Sixten
Published: February 2023

COVID-19 convalescent plasma (CCP) has been explored as one of the treatment options for COVID-19. Results of many cohort studies and clinical trials have been recently published. At first glance, the results of the CCP studies appear to be inconsistent. However, it became clear that CCP is not beneficial if CCP with low anti-SARS-CoV-2 antibody concentrations is used, if it is administered late in advanced disease stages, and to patients who already mounted an antibody response against SARS-CoV-2 at the time of CCP transfusion. On the other hand, CCP may prevent progression to severe COVID-19 when very high-titer CCP is given early in vulnerable patients. Immune escape of new variants is a challenge for passive immunotherapy. While new variants of concern developed resistance to most clinically used monoclonal antibodies very rapidly, immune plasma from individuals immunized by both a natural SARS-CoV-2 infection and SARS-CoV-2 vaccination retained neutralizing activity against variants. This review briefly summarizes the evidence on CCP treatment to date and identifies further research needs. Ongoing research on passive immunotherapy is not only relevant for improving care for vulnerable patients in the ongoing SARS-CoV-2 pandemic, but even more as a model for passive immunotherapy in case of future pandemics with a newly evolving pathogen. Compared to other drugs, which must be newly developed in a pandemic (e.g., monoclonal antibodies, antiviral drugs), convalescent plasma is rapidly available, inexpensive to produce, and can be adaptive to viral evolution by selection of contemporary convalescent donors.
„Ein voller Bauch schläft nicht gut“ – Salutogener Therapieansatz durch Integration der Mayr-Medizin bei Schlafstörungen
Authors: Fegerl Sepp
Published: February 2023

Der gesunde Schlaf ist vielfältigen Störeinflüssen ausgesetzt. Der Verdauungstrakt spielt dabei eine große Rolle. Werden Patientinnen und Patienten mit dem ganzen Spektrum an Schlafstörungen nach den Diagnosekriterien nach Mayr zur Darmgesundheit untersucht, liegt in den meisten Fällen ein überforderter Darm bzw. Verdauungstrakt vor, die den ganzen Organismus belasten. Noch bevor ein medizinischer Krankheitswert erkennbar wird, kann eine Mayr-Therapie präventiv oder kurativ eingesetzt und dadurch können Stoffwechselvorgänge günstig beeinflusst werden: Gewicht, ektopes und viszerales Fett, zirkadianer Rhythmus, Darmgesundheit, Entzündungs-, Hormon- und Immunmodulation, besonders aber auch die Lebensstilfaktoren Ernährung, Bewegung und vegetative Balance.
Pathophysiologie der Schlafapnoe
Authors: Hohmann Claas
Published: February 2023

Obstruktiven Schlafapnoen liegen meist mechanische Ursachen zugrunde. Zumeist handelt es sich um Fettablagerungen in den oberen Atemwegen sowie um eine Verringerung des Lungenvolumens, was zu einem Verlust der kaudalen Traktion der oberen Atemwege führt. Aufgrund des Umstands, dass 60–80% der Betroffenen eine Ernährungsstörung im Sinne einer Adipositas aufweisen, rücken adipöse und darmgestörte Patienten in den Vordergrund. Auch wenn die gesamten Zusammenhänge noch nicht vollständig erforscht sind, zeigt sich, dass der bei Adipösen stark vergrößerte Anteil an viszeralem Fett als endokrines Organ zur Pathogenese der obstruktiven Schlafapnoe beiträgt. Weitere Ursachen der obstruktiven Schlafapnoe können ein meist unbemerkter nächtlicher laryngopharyngealer Reflux sowie intestinale Intoxikationen sein. Der Beitrag beleuchtet die Pathophysiologie der Schlafapnoen unter ernährungs- und darmspezifischen Aspekten und beschreibt davon ausgehende Therapieansätze außerhalb der bekannten konventionellen Verfahren.
Update Motorisches Lernen (3) Instruktionen
Authors: Huber Martin
Published: February 2023

Mit der verbalen Instruktion der Patient*innen lässt sich Aufmerksamkeit und Lernen fördern. Sie ist ein wesentlicher Teil des Therapie- und Lernprozesses, hat ihren Platz im Lernrad und kann reflektiert und zielgerichtet eingesetzt werden.
47.1.4.11 Synthesis of Alkenes by α,β-Dehydrogenation
Authors: Jie X. , Su W.
Published: February 2023

This review describes methods for the synthesis of alkenes by elimination, with a specific focus on α,β-dehydrogenation reactions. It covers the literature published in the period 2011 to early 2020, providing an overview of recently developed transition-metal-catalyzed methods for α,β-desaturation of carbonyl compounds (e.g., ketones, aldehydes, esters, amides, etc.) as well as other functional groups. Key methods covered include palladium-catalyzed dehydrogenation via β-hydride elimination and copper-catalyzed desaturation via a radical pathway, as well as other miscellaneous methods. These approaches provide efficient access to α,β-unsaturated carbonyl compounds, which are important intermediates in the synthesis of diverse valuable organic molecules.
Enhanced terahertz nonlinear response of GaAs by the tight field confinement in a nanogap
Authors: Kim Dasom , Kim Dai-Sik , Choi Geunchang
Published: February 2023

We demonstrated that an incident terahertz peak field amplitude below 0.01 MV/cm can trigger Zener tunneling in a semi-insulating GaAs. Moreover, a transmission decrease with an extinction ratio of 60% was observed in the semi-insulating GaAs with an electric field strength of up to 46 MV/cm (maximum incident peak field of ∼0.29 MV/cm). These experimental results were realized by taking advantage of the nonlinear effects, such as Zener tunneling, impact ionization, and metal–insulator–metal tunneling in 5 nm metallic nanogaps on the GaAs; a strong field was locally confined in the vicinity of these gaps. The 5 nm gap enabled us to lower the voltage across the gap to suppress impact ionization while allowing Zener tunneling. Simulation results indicated that the effective thickness of the semiconductor increased as a function of the gap size. The approach used in this study decreases the threshold incident electric field for nonlinear responses as well as paves the way toward ultrathin high-speed electronic devices and ultrafast light pumps.
Australian climate warming: observed change from 1850 and global temperature targets
Authors: Grose Michael R. , Boschat Ghyslaine , Trewin Blair , Round Vanessa , Ashcroft Linden , King Andrew D. , Narsey Sugata , Hawkins Edward
Published: February 2023

Mean annual temperature is often used as a benchmark for monitoring climate change and as an indicator of its potential impacts. The Paris Agreement of 2015 aims to keep the global average temperature well below 2°C above pre-industrial levels, with a preferred limit of 1.5°C. Therefore, there is interest in understanding and examining regional temperature change using this framework of ‘global warming levels’, as well as through emissions pathways and time horizons. To apply the global warming level framework regionally, we need to quantify regional warming from the late 19th century to today, and to future periods where the warming levels are reached. Here we supplement reliable observations from 1910 with early historical datasets currently available back to 1860 and the latest set of global climate model simulations from CMIP5/CMIP6 to examine the past and future warming of Australia from the 1850–1900 baseline commonly used as a proxy for pre-industrial conditions. We find that Australia warmed by ~1.6°C between 1850–1900 and 2011–2020 (with uncertainty unlikely to substantially exceed ±0.3°C). This warming is a ratio of ~1.4 times the ~1.1°C global warming over that time, and in line with observed global land average warming. Projections for global warming levels are also quantified and suggest future warming of slightly less than the observed ratio to date, at ~1.0–1.3 for all future global warming levels. We also find that to reliably examine regional warming under the emissions pathway framework using the latest climate models from CMIP6, appropriate weights to the ensemble members are required. Once these weights are applied, results are similar to CMIP5.
Quantum speed limit of a single atom in a squeezed optical cavity mode
Authors: Ma Ya-Jie , Gao Xue-Chen , Wu Shao-Xiong , Yu Chang-Shui
Published: February 2023

We theoretically study the quantum speed limit of a single atom trapped in a Fabry–Perot microresonator. The cavity mode will be squeezed when a driving laser is applied to the second-order nonlinear medium, and the effective Hamiltonian can be obtained under the Bogoliubov squeezing transformation. The analytical expression of the evolved atom state can be obtained by using the non-Hermitian Schrödinger equation for the initial excited state, and the quantum speed limit time coincides very well for both the analytical expression and the master equation method. From the perspective of quantum speed limit, it is more conducive to accelerate the evolution of the quantum state for the large detuning, strong driving, and coupling strength. For the case of the initial superposition state, the form of the initial state has more influence on the evolution speed. The quantum speed limit time is not only dependent on the system parameters but also determined by the initial state.
Prediction of battery capacity based on improved model of support vector regression
Authors: Liu Lizhao , Huang Yankai , Huang Shaobing
Published: February 2023

The state of Health (SOH) of new energy lithium batteries is an important indicator to describe the energy decline of new energy, especially the battery decline. It is very important for the service life of new energy equipment, especially equipment based on a lithium battery. Its internal is a high-dimensional nonlinear complex chemical reaction. In this paper, the state of Health (SOH) of a lithium battery is defined according to the capacity to turn the problem of new energy battery capacity into a new problem. At the same time, the multi-dimensional complex nonlinear regression problem is mapped into the physical space, which is described by the phenomenon of the combined action of the quantum radiation field and the quantum gravitational repulsion force in the physical space, and the corresponding quantum radiation equation and abstract equation are used. Finally, the NASA Ames Research Center battery data set is used to verify the results. The verification shows that the algorithm can accurately predict the capacity of the battery to know the SOH of the battery. The model has good learning accuracy, operation speed, and generalization ability.
Research on the construction of new energy microgrids for wind power generation based on green and low carbon
Authors: Yu Changle , Zhang Shuo , Ji Yanchen , Xu Peng
Published: February 2023

At present, the supply mode of fossil fuel as energy in China has caused more and more damage to the environment. In order to meet the demand for sustainable development, research on the construction of new energy microgrids for wind power generation based on green and low-carbon is proposed. Firstly, the equivalent model of the wind power generation system is established, and then the wind power generation new energy microgrid with a wind turbine as the core is built based on the specific value calculated by the model. Finally, the conventional new energy microgrid construction scheme is selected as the comparative object, and the comparative experiment is carried out to prove the practicability of the method. The comparative experimental results show that the microgrid constructed by the proposed green and low-carbon wind power generation new energy microgrid construction method is superior to the traditional construction scheme in operating power, can meet the green and low-carbon energy development needs, and can provide a reference value for similar research schemes.
Research and Analysis of One-button Sequential Control for GIS
Authors: Ding Pengxiang , Yang Chunyue , Lv Xunhao , Wang Yanyi , Li Huaiyu
Published: February 2023

One-button sequential control is one of the advanced applications of the intelligent substation, which is the key technology to promote the deep integration of modern information technology and power grid technology and to construct intelligent operation and inspection systems. Traditional switching depends on manual operation and has a great risk of misoperation. The application of one-button sequential control can effectively reduce misoperation and improve the safety level of power grid switching operations. Through the analysis and research on the key technology of one-button sequential control and combined with the action characteristics and position requirements of the moving contact of disconnector in the opening or closing process, the test analysis method and test control technical requirements of the one-button sequential control are put forward, which provides a certain technical basis for the control and design of the one-button sequential control in the future.
A Triboelectric Transduction Mechanism from Flow-Induced Low-frequency Structural Resonance
Authors: Li Xiaowei , Zhou Yuan , Li Zhongjie , Zhang Dan , Wu Hao , Gong Ying , Zhang Di , Peng Xuzhang
Published: February 2023

A triboelectric nanogenerator (TENG) based on the vortex-induced vibrational resonance is proposed to collect the kinetic flow energy of rivers and oceans. A prototype was fabricated to study the performance of the harvester. Experiments were conducted at flow velocities below 1 m/s. The results show that when flow velocity reaches a low level, the mechanism starts to vibrate; thus, the voltage can be generated, and the voltage increases with the growth of flow velocity. When flow velocity reaches a medium level, the structural resonance take place, resulting in the maximum amplitude of the device and voltage outputs which does not increase further with the growth of flow velocity. When flow velocity reaches a high level, the vortex-induced resonance phenomenon disappears so that amplitude and voltage decrease. The experimental results demonstrate the feasibility of using TENG to harvest vortex-induced vibration energy.
Research on modulation recognition of underwater acoustic communication signal based on deep learning
Authors: Li Yuanyuan , Liang Shucheng
Published: February 2023

Marine information technology plays a important role in the development of marine resources development, marine climate early warning, and other industries. Underwater acoustic communication technology can help us better access marine information. The performance of the underwater acoustic signal modulation recognition algorithm depends on the accuracy of feature extraction. however, due to excessive underwater noise, many traditional algorithms can not recognize features well. For this reason, this paper proposes a modulation recognition network for aquatic communication signals based on deep learning. ResNet can capture the characteristics of deep features and combines ResNet with a modulation recognition network. Finally, the experiment proves the effectiveness of this method.
Continuous-cooling-transformation Diagrams for Boron-low Carbon Micro Alloy Hot Rolled Enamel Steel
Authors: Fu Xuejing , Xu Chun
Published: February 2023

The addition of Element B to micro-alloyed low-carbon steels helps to improve the scale burst resistance of the enameled steel while being able to improve the strength properties of the base steel. It is known that the differences in alloy content change the phase transition temperature and CCT diagram. To test the phase transformation temperature and CCT diagram of B-micro-alloys low carbon steel, this paper uses the thermal expansion method to determine the transformation temperatures Ac1, Ac3, Ar1, and Ar3 with a Gleeble-1500 thermal simulator, and conducts hot compression experiments at 950 °C with a true strain of 0.3 and strain rate of 10 s−1, followed by cooling to room temperature at 0.1, 0.5, 1, 5, 10, and 25 °C/s rates of cooling to room temperature. Based on the expansion diagrams, metallography and hardness are combined to determine the microstructure composition at the corresponding cooling rates. Therefore, the CCT diagrams are plotted. The results show that when the cooling rate is less than 5 °C/s, the phase transformation consists of ferrite and a very small amount of pearlite; when the cooling rate is greater than 5 °C/s, it consists of ferrite, a small amount of pearlite, and bainite, and when the cooling rate is from 5 °C/s to 25 °C/s, it consists of ferrite and bainite.
Analysis of basic performance parameters and temperature effect of SiC-MOSFET
Authors: Li Yaoye
Published: February 2023

With the development of science and technology, traditional silicon-based semiconductor devices can no longer support the development of science and technology. As a new material, silicon carbide has many advantages. In this paper, the working principle of MOSFET is studied, and the characteristics of silicon carbide are sorted and analyzed, based on which the influence of temperature on the basic parameters of the MOSFET device is further studied. It is concluded that temperature affects the leakage current through the influence of threshold voltage drop and carrier: when the device operating voltage is high, the mobility determines the leakage current; at low operating voltage, the threshold voltage determines the leakage current. The research on temperature characteristics of SiC MOSFET is improved in this paper, which promotes the development of microelectronics technology.
The application of coffee husk ash to improve compaction characteristics of clay soil
Authors: Munirwan R P , Mohd Taib A , Taha M R , Abd Rahman N , Munirwansyah M
Published: February 2023

Soil stabilization is the modification process of one or more soil properties mechanically or chemically to generate an improved soil material with the appropriate engineering properties. Recently, stabilization methods utilizing commonly used stabilizing agents are becoming more costly. On the other hand, there is an increasing interest in identifying new green technologies that may be used to improve construction practices. As a result, the search for new materials and improved processes for processing local materials has moved to a priority. Thus, this study was conducted to validate the effectiveness of coffee husk ash (CHA) as a stabilizing agent on the compaction characteristics of clayey soil. To characterize the properties of clayey soil admixed with varying concentrations of CHA, Atterberg limits, grain size distribution, and standard proctor compaction tests were conducted. The soil was mixed with CHA in concentrations ranging from 5% to 25% by dry weight of the soil. Observation indicates CHA progressively enhances soil compaction performance. The pozzolanic and hydration reactions between CHA and the soil may have made the soil more likely to be compacted.
Treatment of Wastewater by Moringa Oleifera and Maize Seeds as Plant-Based Coagulant
Authors: Kasmuri N , Shokree N S A , Zaini N , Ismail N , Miskon M F , Ramli N H , Nayono S E
Published: February 2023

Coagulants are essential in purifying raw water for drinking water safety for consumers. Commonly, aluminium sulphate, a chemical coagulant, is used for water treatment. However, for long-term usage, chemical coagulants can be considered toxic and harmful to the environment due to the accumulation of this substance in the pipeline system, which can create severe health issues if consumed. The natural plant-based coagulant can be a substitute for a sustainable solution in the water treatment coagulation process. This research aimed to determine the efficiency of plant-based materials as coagulants in surface water treatment. Moringa oleifera and maize seeds were chosen as natural coagulants in this investigation since they are both locally available plant-based materials. Here, this research aims to study the ability of moringa oleifera seed and maize seed as plant-based coagulants in enhancing the effluent quality of the wastewater treatment plant of UiTM Dengkil Selangor. A jar test experiment was used to assess the capacity of moringa oleifera and maize as natural coagulants. The results comprise turbidity removal by 92% (mixed of moringa oleifera seed and maize seed), the chemical oxygen demand (COD) of 95% reduction rate using moringa oleifera seed. The biochemical oxygen demand (BOD) for 88% removal by moringa oleifera seed, ammonia-nitrogen removal of 12% (moringa oleifera seed) and total suspended solids (TSS) of 100% reduction rate using mixed moringa oleifera seed and maize seed for the effluent sample. Thus, it can be recognized that moringa oleifera and maize seeds can be an alternative solution to replace the chemical coagulants in the treatment systems.
Thermal analysis under static and fatigue conditions on HDPE
Authors: Santonocito D , Cucinotta F , Guglielmino E , Risitano G
Published: February 2023

High Density Polyethylene (HDPE) represents one of the best choices for water and gas distribution pipeline thanks to its light weight and good mechanical performance. One of the strengths of this plastic material is the possibility to join it via welding adopting a procedure according to the standard. However, the welding procedure can severally alter the mechanical performance of the material under service loads. In the present work comparison between virgin and welded HDPE specimens is carried out adopting rapid approaches, such as the Risitano’s Thermographic Method and the Static Thermographic Method, monitoring the evolution of the specimen’s superficial temperature under static tensile and fatigue tests. Mechanical performance has been compared, as well as the fatigue limit obtained with traditional fatigue tests, showing good agreement. Reliable fatigue data have been obtained in a very short amount of time and with few specimens by adopting Energy Methods.
Influence of the wear rings on the buckling behaviour of hydraulic actuators
Authors: Arcieri E V , Baragetti S
Published: February 2023

During their use, hydraulic actuators are generally subjected to compressive loads which can induce buckling. In this work the critical load of a hydraulic actuator was determined for various boundary conditions and types of wear rings by theoretical and numerical models. In the theoretical model, the actuator was modelled as two connected beams, with different sections. The contribution of the wear rings on the critical load of the actuator was determined through numerical simulation based on the finite element method. The results of the mathematical model are similar to the results provided by the finite element analyses. The contribution of the investigated wear rings stiffness is very low for the materials considered for these components in this paper.
Shape optimization of 2D beam-structures to obtain the uniform strength
Authors: Iandiorio C , Milani D , Salvini P
Published: February 2023

This paper provides a new method to design the optimal shape of 2D frame structures even (or especially) if not statically determined. The optimization here addressed involves obtaining the uniform strength of the whole structure, but the proposed procedure can be followed for other optimization goals. Two types of beam cross-sections are studied, in which the solution in terms of balance, kinematic and beam-shape is found analytically and involves six unknowns for every beam element. For frame structures, some internal and external constraint conditions must be satisfied; using the analytical solution within the boundary conditions, the optimization problem boils down to finding the roots of a non-linear system. This way allows to work inside the optimization workspace, avoiding the use for each iteration of other solvers (e.g. F.E. software) and obtaining the solution with a high-computation speed. Two tests are shown, which result in a uniform-strength behaviour of the maximal stress at every cross section, and a lightness gain higher than 70% by respect to the reference initial structure. This technique can be extended to other types of cross-sections or 3D frame structures.
Design and simulation of a wireline core drilling device for near-shore applications
Authors: Cocci M , Barletta S , Berzi L , Capitani R , Delogu M , Mariottoni E , Sacchetto M , Pugi L
Published: February 2023

The PROTEUS project involves the construction of a self-propelled and floating amphibious machine for near shore geological surveys. In this context, the development of a wireline core drilling device was tackled, evolving with respect to existing models and responding to the specificities of the new application. In the preliminary phase, comparative research was carried out both through market research and through reverse engineering activities on core drill models deemed suitable for the purpose, thus identifying the functional priorities and criticalities of the existing material through the ex-post analysis of the subject elements to wear and tear. Once the requirements of the new core drilling device were formalized, the constructive layout was defined, giving priority to functions such as sample management, interlocking and rapid disengagement from the drilling actuation system. The construction details of the mechanical coupling profiles were then optimized by simulation in a multibody software environment, in order to ensure full functionality even in harsh environments, typical of the application, making an advancement with respect to the previously identified reference solutions. Finally, the executive design of the component was carried out by introducing the corrections deriving from the simulation results and considering different solutions in relation to the material adopted and its production needs through machining processes.
Residual stress measurements on a deep rolled aluminum specimen through X-Ray Diffraction and Hole-Drilling, validated on a calibration bench
Authors: Beghini M , Grossi T , Santus C , Seralessandri L , Gulisano S
Published: February 2023

Residual stress measurements are notably affected by a high sensitivity to errors in input data. Measurements should then be presented together with an estimation of their accuracy. A common strategy is to carry out more measurements and/or to compare the results of different techniques. However, error contributions due to biases could be dangerously left unseen. In a previous work, the authors presented a calibration bench which can impose a known bending stress distribution on a specimen while simultaneously performing X-Ray Diffraction (XRD) or Hole-Drilling Method (HDM) residual stress measurements. Since the external load can freely be applied and removed, the superposition principle can be exploited to simultaneously identify either the reference bending stress distribution or the actual residual stress distribution, with the same experimental setup. A deep rolling treatment was measured and analyzed on the calibration bench with both XRD and HDM. First, residual stresses on the surface were evaluated with XRD measurements, then electrochemical material removal was performed to investigate stresses at higher depths. After that, HDM measurements were carried out and compared with the results of XRD. Both methods were also used to identify the known bending stresses, providing an additional validation of the residual stress results.
Simulated and real world tests to compare drivers performance in dynamic wireless technology perspective
Authors: Berzi L , Barbieri R , Uggiosi D , Delogu M
Published: February 2023

The ongoing electrification of road vehicles needs to be supported by proper growth of charging infrastructure. In this context, dynamic wireless charging can provide a number of advantages, main being the possibility to extend vehicle range without increasing on board battery capacity, potentially reducing cost, mass, and tank-to-wheel energy consumption. The development of such solutions however poses various questions, including the acceptance and the capability of users in driving according to infrastructure characteristics; in particular, the misalignment reduction while a driver follows a straight path positively influence the charging efficiency in dynamic wireless technology. In this paper, authors describe a tests campaign to determine driving performances using both a simulator and a real world equipped vehicle. The research question of this paper is to assess and quantify differences between the two approaches. To reach this objective, in a first phase, data have been collected through a driving simulator (i.e. a full car body mounted on a parallel linked kinematics with a large screen, proposing a virtual city scenario), and in a second phase through a car equipped with a camera. As a post processing phase, statistical tools have been used to describe driving performance indexes and related impacts on wireless charging infrastructure by determining the secondary voltage on the vehicle. Data coming from the activity will be functional to be used by scenario analyst to develop characterization tests only with a simulative approach to decrease costs.
Time-of-Flight measurement on a rail by laser-ultrasound
Authors: Vangi D , Gulino M S
Published: February 2023

Stress states of thermal origin on the Continuously Welded Rail (CWR) are a source of possible inconvenience due to winter breakage or dangerous summer buckling. To date, alongside procedures based on the measurement of rail displacements or rail cutting, several methods for measuring the stress state in the rail have been proposed, based on X-ray diffraction, Barkhausen noise, and the acoustoelastic effect; all these approaches have some critical issues for extensive use in the field. The acoustoelastic method is based on the dependence of the ultrasonic wave speed on the stress state of the material and involves the measurement of the Time of Flight (ToF). Because of the modest acoustoelastic effect, the speed variations caused by the stress states are very limited, which is reflected in the need for ToF measurements with an accuracy of the order of a few nanoseconds.

In the past, the research group successfully used the acoustoelastic method to monitor a 3 km portion of a rail between Florence and Pontassieve, with fixed measurement stations, where the ultrasonic probes were permanently positioned on the neutral axis of the rail. Today, the need is to have a mobile measuring system, which can measure in several points or even continuously as the system moves along the rail. This appears to be possible through the use of, for example, non-contact systems such as those based on laser and air-coupled probes or lasers alone. In the first case, however, the acoustic wave partly propagates in the air before reaching the piezoelectric probe, and this path is subjected to variations in temperature and thus ToF. In the second case, the ultrasonic waves are generated and detected by optical methods with lasers. For the generation of acoustic waves, the use of pulsed lasers has become a widespread, reliable practice, which allows researchers to obtain signals of high amplitude and wide bandwidth. For the reception of the acoustic signal, the precision required in the measurement involves careful analysis and experimentation to identify the most appropriate laser technique, depending on the quality of the surface on which the measurement is performed, the sensitivity of the method, and the possibility of taking measurements while moving.

In the present work, a technique for laser detection of ultrasonic waves, Optical Beam Deflection (OBD), is analysed. The technique is based on the deflection of an optical beam: the beam irradiates the surface of the rail and is reflected at angles that depend on the orientation of the surface at the point of measurement, which is perturbed by the passage of the acoustic wave. The technique, developed in the 1990s, has limited applications in non-destructive testing, where interferometer-based techniques are more widespread; still, they require more sophisticated and expensive equipment. Different experimental arrangements and initial experimental results are analysed and presented, to optimise their sensitivity and verify their suitability for the purpose.
A “Wild and Ambiguous Medium”: Democracy, Interiority, and the Early American Epistolary Novel
Authors: Koenigs Thomas
Published: February 2023

This essay argues that early American novelists’ sustained commitment to epistolary fiction reflects their recognition that the mediated access it offered to inner life made it a potent vehicle for highlighting the limits of our ability to decipher the concealed interiorities of other people. Faced with the question of how novels might best prepare readers for republican social and political life, novelists such as Charles Brockden Brown and Susanna Rowson turned to this increasingly outmoded form because it foregrounded the uncertainties inherent in reading inner life. Eschewing third-person fiction’s fantasy of direct access to another mind, these novels foster an epistemological humility regarding other interiorities that would be valuable in negotiating civic life in the early republic. While early American novels have long been regarded as encouraging sympathetic identification as a means of establishing political union, novels such as Brown’s Clara Howard and Rowson’s Sincerity instead harness the epistolary novel’s partial, uncertain revelations of interiority to highlight our inability to access fully someone else’s thoughts or feelings. These novels warn readers that successfully navigating the epistemological challenges of this new democratic social order requires resisting the fantasy that another person’s true feelings can ever be fully known.Rowson and Brown saw epistolary novels as a means of not just teaching Americans how to read inner life, but also of cautioning them that they could never do so with certainty.
“The Mound of His Back”: The Profession of Literature and the Fear of the Mob
Authors: McCann Sean
Published: February 2023

Recent novels respond to the current crisis of democracy by invoking literary fiction as a means to cultivate empathy and as a model for more inclusive forms of community. But such novels also often defend the mission of literature by casting service workers and popular voters as foils and by defining those figures as ignorant and irrational. Reflecting the educational cleavage that shapes both literary culture and the current political environment, such defenses of literature point toward the class limitations of contemporary liberalism and, in this respect, are not good models of democracy.This is a sentence that expresses a judgment about the characters it depicts, and the judgment is clear: they are poor, ugly, and stupid.
Narrative Disorders: Surveillance, Truth, and Democracy in Malka Older’s Centenal Cycle
Authors: McAlister Melani
Published: February 2023

Malka Older’s Centenal Cycle comprises three novels that, taken together, reimagine democracy after the end of the nation-state. The series tells an eerily timely story of a late twenty-first-century global election being undermined by an attack on the election apparatus, run by a ubiquitous surveillance system called Information. When Information is attacked, the global election goes haywire, and our protagonists, most of whom work for Information, are forced to dash around the world trying to save the system. Whether the system is worth saving and what democracy needs to survive are two of the questions that occupy the multi-racial and cosmopolitan women at the center of this sprawling science fiction world, richly conceptualized by Older, a Latinx writer and “Senior Global Futures Scientist” at Arizona State University.The novels postulate that we cannot radicalize and reinvigorate democracy without reducing its scale. The price for that will be expansions of technological reach and the real peril of global conspiracy across small states. In that world, narrative is currency, and overreading a practice of freedom.
Indigenous Cosmopolitanism and Its Discontents: Decolonization and Democracy in Leslie Marmon Silko’sGardens in the Dunes
Authors: Young Alex Trimble
Published: February 2023

Over the course of the 1990s, the reception of Almanac of The Dead’s (1991) strident decolonial allegory propelled Leslie Marmon Silko to the center of debates about the future of both liberal democracy and Indigenous sovereignty struggles. This article revisits how and why Silko was cast as a representative of liberal multiculturalism by scholars who championed and critiqued US liberalism in the wake of the Cold War, and reads her 1999 Gardens in the Dunes, a novel she describes as forming, with Almanac, a diptych “about capitalism and the effects of capitalism” (“Conversations” 118), in relation to these critical debates. It argues that the conclusion of Gardens in The Dunes engages with the Western genre as an allegorical means toward situating Silko’s commitment to Indigenous sovereignty in relation to the questions about the relation among law, violence, and democracy that animate so many Cold War westerns. The political orientation that emerges from this unlikely engagement with settler colonialism’s most recognizable genre is an allegorical vision of an Indigenous cosmopolitanism committed to both decolonial struggle and the universal liberatory ideals that liberalism espouses yet inevitably betrays.Through an oblique but unmistakable engagement with the Western genre . . . Gardens in the Dunes reaffirms Silko’s commitment to a broad vision of decolonization celebrating the universal liberatory ideals that US liberalism has betrayed.
The Limits of Latinx Representation
Authors: Nugent Carlos Alonso
Published: February 2023

This essay considers a crisis in the literary form we call “the novel” and the political form we call “democracy.” As many scholars have argued, these forms had a crucial convergence in the late eighteenth century: while novels made it easier for subjects to identify as rational decision-makers in secular social worlds, democracy became these subjects’ preferred way of institutionalizing political power. To be sure, most early novels helped consolidate the upper classes, but with each passing decade, an increasing number have sought to open democracy to the disenfranchised. However, when contemporary novels take up the cause of unauthorized migration, they often struggle to raise cultural awareness—and overwhelmingly fail to produce political change. In this context, Valeria Luiselli’s Lost Children Archive (2019) tries to see—and see beyond—three limits of Latinx representation. Against a literary lineage that prizes complete portrayals of exemplary people, it demonstrates that completion and comprehension are often impossible. Similarly, amidst a culture industry in which “representation matters,” it explains why the category “Latinx” is usually inadequate to the diversity of migrant life. Finally, in a nation said to be a “representative democracy,” it shows how divisions between citizens and migrants are untenable.Lost Children Archive reenergizes the novel in/of democracy by reckoning with its limits. . . . whereas many novels have enabled their readers to feel like they lived in democracies, Lost Children Archive confronts us with other ways of imagining and institutionalizing political life—and political death.
Sovereign Flows and the Obligation of Repayment
Authors: Pexa Christopher
Published: February 2023

Stephen Graham Jones’s 2020 novel, The Only Good Indians, depicts the haunting and killing of four Blackfeet friends—Ricky, Lewis, Cassidy, and Gabriel—by the spirit of an elk cow called “Elk Head Woman,” who stalks the men after they have killed her and her unborn calf. Their punishment, and the unpayability of their debt to the ghost, entail asking what lies beyond a regime of rights when those rights have been judged to be always already ignorable by settler-colonial society. But Elk Head Woman’s haunting also positions violence against the land (via fracking) and its more-than-human inhabitants as a metonym for settler-colonial violence against Indigenous women and girls. This essay asks what justice may look like beyond a framework of individual rights that create a temporal enclosure, tying people and harm to moments in time and specific places, arguing that the mobility of intergenerational debt and its unpayable reparations across times and places constitute a sovereign flow—the enduring movement of an ethical–political object (here, the elk-Blackfeet law) created between sovereign peoples (human and more-than-human) that persists apart from the settler-colonial state across whose legal and geographic spaces and time the flow moves.

[The Only Good Indians’] fictional dramatizing of settler-Indigenous-nonhuman relations shows a world apart from settler-colonial social justice and forms of democratic inclusion: a haunting that . . . [refuses] violence against Indigenous women and ongoing forms of capitalistic extraction on tribal lands.
The Critical Electorate: On Democracy and Disenchantment
Authors: Fleissner Jennifer L
Published: February 2023

This essay uses Chantal Mouffe's work in The Democratic Paradox (2000) to think through the paradoxical status of democracy in this special issue. At a moment when democracy is under authoritarian threat worldwide, contributors often treat it not as an imperiled good but as a misty future horizon. Moreover, it is seen as held back most by a commitment to “liberal” values, though little consensus prevails here about this term’s meaning. This stance then dovetails with a predilection for speculative rather than realist fictional forms. And yet the essays in fact display an ongoing unacknowledged allegiance to various actual liberal ideals. Together with the markedly strong disagreements evident across the issue as a whole, this fact speaks to Mouffe's affirmation of an “agonistic”—but, crucially, not “antagonistic”—politics, in which “liberalism” and “democracy” need to remain ideas in necessary and essential tension with one another. Their clash demonstrates the way that modernity's lack of transcendent grounding generates a situation of ongoing and irresolvable value conflict. This essay then suggests that a version of this conflict plays out in the novel in formal terms as well, as an unresolved dual allegiance both to realism and to what exceeds its bounds.[The essays'] very embrace and even hyperbolization of liberal idioms of individual choice, freedom, and so on . . . suggests that we may have a more complicated situation on our hands than the by-now programmatic affirmations of “democracy” and repudiations of “liberal” can effectively address.