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This paper presents a modified super-twisting control algorithm that drives the state of a scalar system at the origin for a predefined-time with a low control cost. The designed control law is used for stabilizing the state of a scalar permanent-magnet synchronous motor system in three different cases: disturbance-free, with rate-bounded disturbances, and with both rate-bounded deterministic disturbances and stochastic noises. The performance of the proposed algorithm is validated by numerical simulations, and comparisons to other predefined-time convergent control laws are provided.

This paper presents a flexible and scalable battery system for maritime transportation, integrating modular converters and hybrid battery technologies that are effectively implemented in real-world scenarios. The proposed system is realized with modular DC-DC converters, which do not require complex design and control or a high number of components and combine high-power (HP) and high-energy (HE) battery cells to optimize the energy and power requirements of vessel operations without oversizing the energy storage system. Moreover, the modular design ensures flexibility and scalability, allowing for easy adaptation to varying operational demands. In particular, the system topology, control mechanisms, and communication protocols are explained in this paper. The concept has been validated through simulations and real-scale laboratory tests, demonstrating its effectiveness. Key results highlight the system’s ability to maintain the DC bus voltage while operating at high efficiency (ranging from 97% to 98%) under different load conditions, supported by reliable and demanding real-time communication using the EtherCAT standard. This real-time capability has been validated, and related results are presented in this paper, showing a synchronization accuracy below 200 ns between two modules and a stable control at a cycle time of 400 µs. This approach offers a promising solution for reducing greenhouse gas emissions in the maritime industry, aligning with global sustainability goals.

Numerous numerical studies have been carried out in recent years that simulate different aspects of exoplanets’ magnetosphere and stellar winds. These studies have focused primarily on hot Jupiters with sun-like stars. This study addresses the challenges inherent in utilizing existing MHD codes to model hot Jupiter-star systems. Due to the scaling of the system and the assumption of a uniformly flowing stellar wind at the outer boundary of the simulation, MHD codes necessitate a minimum distance of greater than 0.4 au for a Jupiter-like planet orbiting a sun-like star to avoid substantial violations of the code’s assumptions. Additionally, employing the GAMERA (Grid Agnostic MHD for Extended Research Applications) MHD code, we simulate star-planet interactions considering various stellar types (Sun-like and M Dwarf stars) with both Jupiter-like and rocky planets positioned at varying orbital distances. Furthermore, we explore the impact of tidal locking on the total power within the magnetosphere-ionosphere systems.

We examine the dynamics of a liquid bridge between a sphere and a flat plate being separated from each other. Unlike previous research, this paper focuses on the case where the viscosity of the bridge is lower than that of the external fluid within which the particle, the plate, and the liquid bridge are immersed. For the general case of a viscosity mismatch between the bridge fluid and the external fluid, we develop a lubrication theory-based model for the viscous force during separation. The model predicts that a low viscosity bridge reduces the force as compared to both - separation without a liquid bridge, or separation with a bridge of matched viscosity. The magnitude of force reduction is expected to be more severe at small sphere-plate separations and at large bridge volumes. Experiments confirm all these predictions qualitatively, but unexpectedly the magnitude of the reduction is even larger than predicted. Experiments also find that the bridge length at rupture for specified velocity exceeds that for quasistatic rupture by an amount that increases with the squareroot of the velocity. Although we only examine bridges between a plate and a spherical particle, all results are expected to apply for bridges between a pair of particles as well.

Quantifying spatial and temporal patterns of the actual evapotranspiration (ET) using Earth observation data can significantly contribute to the accurate and transparent monitoring of sustainable development goals (SDGs) target 6.4, which focuses on the increase of the water-use efficiency and sustainable freshwater withdrawals. Irrigated agriculture is by far the largest consumer of freshwater worldwide, and ET can serve as a direct proxy of crop water use. Various ongoing initiatives encourage the use of remote sensing data for the monitoring of SDG 6.4, including the WaPOR portal run by the Food and Agriculture Organization of the United Nations. However, none of these initiatives use Copernicus satellite and modeled data to the fullest extent. Copernicus provides operational high-quality data freely and openly, contains all the inputs required for ET modeling, and has long-term continuity and evolution plans, thus allowing for the establishment of baseline for SDG 6.4 and continuous monitoring in mid- and long term. In this study, we evaluate the utility of Copernicus data for this task with WaPOR products serving as a comparison benchmark. Thus, the modeled ET has to be able to accurately capture the field-scale activity at 10-day timesteps while also scaling to national coverage and providing consistent estimates at different spatial resolutions, ranging from tens to hundreds of meters. Results indicate that Copernicus-based ET can reach a correlation of 0.9, mean bias of 0.3 mm/day, and root-mean-square error of less than 1 mm/day when compared against the field lysimeter and eddy covariance measurements, and with proper approach, can achieve a better spatial-scale consistency than WaPOR data. This sets a path toward the Copernicus-based ET product and its use within the SDG monitoring and reporting.

HIV infection is associated with multisystemic manifestations due both to secondary infections caused by a decrease in the CD4+ T-cell count and to the pathogenicity of the HIV virus itself. A common renal manifestation is HIV-associated nephropathy, which is frequently seen in the African population with the APOL1 gene mutation; however, other forms of glomerulopathy such as IgA nephropathy, commonly noted in other ethnicities, are also seen. Vasculitis has rarely been associated with HIV infection and mainly involves small blood vessels, although any size of blood vessel may be involved. The association of Henoch-Schonlein purpura (HSP) with HIV is rare and not well understood. We describe a 53-year-old African American woman with a newly diagnosed HIV infection who presented with a purpuric rash over the bilateral lower extremities with haematuria. Initial work-up revealed renal dysfunction with elevated ESR. Urinalysis was positive for glomerular haematuria and sub-nephrotic range proteinuria. Serum complement level, c-antineutrophil cytoplasmic antibody (ANCA), p-ANCA and anti-nuclear antibody (ANA) were negative. Renal biopsy revealed mesangial IgA deposits with crescent glomerulopathy and fibrinoid necrosis, while skin biopsy revealed leucocytoclastic vasculitis. A diagnosis of HSP was made based on American College of Rheumatology (ACR) criteria. The patient’s renal function and purpura improved with a 5-day course of steroid pulse therapy. This case of HSP in a newly diagnosed HIV patient is unusual for the presence of crescentic glomerulopathy.

Abstract In this study, the Global Ionosphere Thermosphere Model is utilized to investigate the inter‐hemispheric asymmetry in the ionosphere‐thermosphere (I‐T) system at mid‐ and high‐latitudes (|geographic latitude| > 45°) associated with inter‐hemispheric differences in (a) the solar irradiance, (b) geomagnetic field, and (c) magnetospheric forcing under moderate geomagnetic conditions. Specifically, we have quantified the relative significance of the above three causes to the inter‐hemispheric asymmetries in the spatially weighted averaged E‐region electron density, F‐region neutral mass density, and horizontal neutral wind along with the hemispheric‐integrated Joule heating. Further, an asymmetry index defined as the percentage differences of these four quantities between the northern and southern hemispheres (|geographic latitude| > 45°) was calculated. It is found that: (a) The difference of the solar extreme ulutraviolet (EUV) irradiance plays a dominant role in causing inter‐hemispheric asymmetries in the four examined I‐T quantities. Typically, the asymmetry index for the E‐region electron density and integrated Joule heating at solstices with F10.7 = 150 sfu can reach 92.97% and 38.25%, respectively. (b) The asymmetric geomagnetic field can result in a strong daily variation of inter‐hemispheric asymmetries in the F‐region neutral wind and hemispheric‐integrated Joule heating over geographic coordinates. Their amplitude of asymmetry indices can be as large as 20.81% and 42.52%, which can be comparable to the solar EUV irradiance effect. (c) The contributions of the asymmetric magnetospheric forcing, including particle precipitation and ion convection pattern, can cause the asymmetry of integrated Joule heating as significant as 28.43% and 34.72%, respectively, which can be even stronger than other causes when the geomagnetic activity is intense.

This paper presents a review of advanced architectures based on the partial power processing concept, whose main objective is to achieve a reduction of the power processed by the converter. If the power processed by the converter is decreased, the power losses generated by the power converter are reduced, obtaining lower sized converters and higher system efficiencies. Through the review 3 different partial power processing strategies are distinguished: Differential Power Converters, Partial Power Converters and Mixed strategies. Each strategy is subdivided into smaller groups that entail different architectures with their own advantages and disadvantages. Also, due to the lack of agreement that exists in the sources around the naming of the different architectures, this paper seeks to stablish a nomenclature that avoids confusion when indexing this type of architectures. Regarding Partial Power Converters an extensive application oriented description is also developed. Finally, the main conclusions obtained through the review are presented.

Abstract Background Radiation therapy is a mainstay in the treatment of esophageal cancer (EC) patients, and photon radiotherapy has proved beneficial both in the neoadjuvant and the definitive setting. However, regarding the still poor prognosis of many EC patients, particle radiation employing a higher biological effectiveness may help to further improve patient outcomes. However, the influence of clinically available particle radiation on EC cells remains largely unknown. Methods Patient-derived esophageal adenocarcinoma and squamous cell cancer lines were treated with photon and particle irradiation using clinically available proton (1H), carbon (12C) or oxygen (16O) beams at the Heidelberg Ion Therapy Center. Histology-dependent clonogenic survival was calculated for increasing physical radiation doses, and resulting relative biological effectiveness (RBE) was calculated for each radiation modality. Cell cycle effects caused by photon and particle radiation were assessed, and radiation-induced apoptosis was measured in adenocarcinoma and squamous cell EC samples by activated caspase-3 and sub-G1 populations. Repair kinetics of DNA double strand breaks induced by photon and particle radiation were investigated. Results While both adenocarcinoma EC cell lines demonstrated increasing sensitivities for 1H, 12C and 16O radiation, the two squamous cell carcinoma lines exhibited a more heterogeneous response to photon and particle treatment; average RBE values were calculated as 1.15 for 1H, 2.3 for 12C and 2.5 for 16O irradiation. After particle irradiation, squamous cell EC samples reacted with an increased and prolonged block in G2 phase of the cell cycle compared to adenocarcinoma cells. Particle radiation resulted in an incomplete repair of radiation-induced DNA double strand breaks in both adenocarcinoma and squamous cell carcinoma samples, with the levels of initial strand break induction correlating well with the individual cellular survival after photon and particle radiation. Similarly, EC samples demonstrated heterogeneous levels of radiation-induced apoptosis that also corresponded to the observed cellular survival of individual cell lines. Conclusions Esophageal cancer cells exhibit differential responses to irradiation with photons and 1H, 12C and 16O particles that were independent of tumor histology. Therefore, yet unknown molecular markers beyond histology may help to establish which esophageal cancer patients benefit from the biological effects of particle treatment.

Abstract Background Fibrosis is a delayed side effect of radiation therapy (RT). Connective tissue growth factor (CTGF) promotes the development of fibrosis in multiple settings, including pulmonary radiation injury. Methods To better understand the cellular interactions involved in RT-induced lung injury and the role of CTGF in these responses, microarray expression profiling was performed on lungs of irradiated and non-irradiated mice, including mice treated with the anti-CTGF antibody pamrevlumab (FG-3019). Between group comparisons (Welch’s t-tests) and principal components analyses were performed in Genespring. Results At the mRNA level, the ability of pamrevlumab to prolong survival and ameliorate RT-induced radiologic, histologic and functional lung deficits was correlated with the reversal of a clear enrichment in mast cell, macrophage, dendritic cell and mesenchymal gene signatures. Cytokine, growth factor and matrix remodeling genes that are likely to contribute to RT pneumonitis and fibrosis were elevated by RT and attenuated by pamrevlumab, and likely contribute to the cross-talk between enriched cell-types in injured lung. Conclusions CTGF inhibition had a normalizing effect on select cell-types, including immune cells not typically regarded as being regulated by CTGF. These results suggest that interactions between RT-recruited cell-types are critical to maintaining the injured state; that CTGF plays a key role in this process; and that pamrevlumab can ameliorate RT-induced lung injury in mice and may provide therapeutic benefit in other immune and fibrotic disorders.

Background: Mesenchymal stem cells (MSCs) participate in the regeneration of tissue lesions induced by antimetabolite chemotherapy; however, the influence of this class of anti-cancer compounds on the stem cells remains largely unknown. Methods: The survival of MSCs after exposure to 5-fluorouracil (5-FU) and gemcitabine was measured by viability and clonogenic assays. MSC morphology, surface marker expression, adhesion potential, cellular velocity and differentiation potential were determined after antimetabolite treatment. Cell cycle distribution and apoptosis were assessed using flow cytometry, and senescence induction was evaluated by beta-galactosidase staining. Gene expression arrays were used to analyze the expression of enzymes involved in DNA metabolism and multidrug resistance. Results: Here, we show that human primary bone marrow MSCs are relatively resistant to treatment with the widely used antimetabolite drugs 5-FU and gemcitabine. The stem cells were able to largely retain their functional abilities and defining stem cell traits after antimetabolite exposure. MSCs surface markers were found stably expressed, and the characteristic multi-lineage differentiation potential was maintained irrespective of 5-FU or gemcitabine treatment. High expression levels of enzymes involved in DNA metabolism and multidrug resistance transporters may contribute to the resistance to antimetabolite chemotherapy. Discussion: The observed resistance and functional integrity may form the basis for further investigations of MSCs as a potential therapy for antimetabolite-induced tissue damage. Keywords: Mesenchymal stromal cells (MSCs), Mesenchymal stem cells (MSCs), Antineoplastic agents, Fluorouracil, Gemcitabine, Neoplasms, Stem cells

The polar cap boundary (PCB) is a fundamental indicator of magnetospheric activities especially during a substorm cycle. Taking a period on 8 March 2008 as an example, we investigate the location of PCB and its dynamics during a substorm event. The PCB location is determined from the Piecewise Parabolic Method with a Lagrangian Remap (PPMLR) -Magnetohydrodynamic (MHD) simulation data and Defense Meteorological Satellite Program (DMSP) observations, respectively. Model-observation comparison indicates that the PPMLR-MHD model gives a reliable estimate of PCB location during a complex substorm sequence. We further analyze the evolution of PCB in that period. The polar cap expands under southward interplanetary magnetic field (IMF), since the low-latitude dayside reconnection produces new open magnetic flux. Meanwhile, more solar wind energy enters and stores in the magnetosphere with the decreasing SML (SuperMAG Auroral Lower) index. After the substorm expansion onset, the polar cap contracts for a while due to the explosive increase of nightside reconnection. When the IMF direction turns northward, the polar cap contracts continuously, since the dayside reconnection ceases and no more open magnetic flux are supplied, and the storage energy in the magnetosphere releases with the increasing SML index. The model results are in good accord with the features from observations.

En el yacimiento solutrense de La Cueva de Ambrosio se han encontrado durante las campañas de 1992 y 1994 un conjunto de representaciones artísticas parietales pintadas y grabadas del Paleolítico Superior. Entre los grabados del panel I, se ha descifrado una excelente silueta de caballo, una representación de ave, unos protomos de bóvido y de caballo, así como otros trazos todavía no interpretados. En la parte inferior del panel existen pinturas, poco visibles a causa de una colada calcítica y de momento no es posible interpretar ninguna representación figurativa. En el panel II se han identificado un espléndido caballo pintado en ocre rojo, otros dos caballos grabados, un protomos de caballo pintado en negro y gran cantidad de líneas incisas en trazo múltiple, así como otros restos pictóricos todavía por identificar. La excepcionalidad del hallazgo reside en el hecho de poder interrelacionar perfectamente estas muestras de arte con los niveles arqueológicos claramente definidos desde el punto de vista cultural y cronoestratigráfico (ca. 16000 B.P. Solutrense Superior y Solutrense Superior Evolucionado) del mismo yacimiento.