Antiferromagnets offer a unique combination of properties including the radiation and magnetic field hardness, the absence of stray magnetic fields, and the spin-dynamics frequency scale in terahertz. Recent experiments have demonstrated that relativistic spin-orbit torques can provide the means for an efficient electric control of antiferromagnetic moments. Here we show that elementary-shape memory cells fabricated from a single-layer antiferromagnet CuMnAs deposited on a III-V or Si substrate have deterministic multi-level switching characteristics. They allow for counting and recording thousands of input pulses and responding to pulses of lengths downscaled to hundreds of picoseconds. To demonstrate the compatibility with common microelectronic circuitry, we implemented the antiferromagnetic bit cell in a standard printed circuit board managed and powered at ambient conditions by a computer via a USB interface. Our results open a path towards specialized embedded memory-logic applications and ultra-fast components based on antiferromagnets.
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
Microgrids (MGs) and energy communities have been widely implemented, leading to the participation of multiple stakeholders in distribution networks. Insufficient information infrastructure, particularly in rural distribution networks, is leading to a growing number of operational blind areas in distribution networks. An optimization challenge is addressed in multi-feeder microgrid systems to handle load sharing and voltage management by implementing a backward neural network (BNN) as a robust control approach. The control technique consists of a neural network that optimizes the control strategy to calculate the operating directions for each distributed generating point. Neural networks improve control during communication connectivity issues to ensure the computation of operational directions. Traditional control of DC microgrids is susceptible to communication link delays. The proposed BNN technique can be expanded to encompass the entire multi-feeder network for precise load distribution and voltage management. The BNN results are achieved through mathematical analysis of different load conditions and uncertain line characteristics in a radial network of a multi-feeder microgrid, demonstrating the effectiveness of the proposed approach. The proposed BNN technique is more effective than conventional control in accurately distributing the load and regulating the feeder voltage, especially during communication failure.
- Keywords
- Backward NN, Communication latencies, Distributed control, Multi-level control, NN microgrid control, Renewable energy sources,
- Publication type
- Journal Article MeSH
Wastewater effluents and global warming affect freshwater ecosystems and impact their crucial biodiversity. Our study aimed at characterizing individual and combined impacts of wastewater effluent and increased water temperature (as one aspect of climate change) on model freshwater communities. We tested the effect of experimental treatments on genetic diversity, survival, body weight, total lipid content, lipidome and metabolome of individual species as well as community composition and phylogenetic diversity. In a 21-day mesocosm experiment we assessed the responses of a simplified freshwater food web comprising of moss and seven species of benthic macroinvertebrate shredders and grazers (mayflies, stoneflies, caddisflies and amphipods) to four treatments in a full factorial design: control, increased water temperature, wastewater and a multiple stressor treatment combining increased temperature and wastewater. Physiological responses varied among taxa, with species-specific sensitivities observed in survival and lipid content. The lowest total lipid content was observed in caddisflies and a mayfly subjected to multiple stressor treatment. The effects of stressors were reflected in the altered metabolic pathways and lipid metabolism of the individual taxa, with differential treatment effects also observed between taxa. A notable decrease in phylogenetic diversity was observed across all experimental communities. Gammarus fossarum demonstrated a high susceptibility to environmental stressors at the genetic level. Hence, while commonly used indicators of ecosystem health (e.g. community composition) remained stable, molecular indicators (e.g. phylogenetic diversity, metabolome and lipidome) responded readily to experimental treatments. These findings underscore the vulnerability of macroinvertebrates to environmental stressors, even over relatively short exposure periods. They highlight the importance of molecular indicators in detecting immediate ecological impacts, offering valuable information for conservation strategies and understanding the ecological consequences in freshwater ecosystems.
- Keywords
- Aquatic macroinvertebrates, Aquatic-terrestrial subsidies, Climate change, Model community, Multiple stressors, Pollution,
- MeSH
- Invertebrates * physiology MeSH
- Biodiversity * MeSH
- Phylogeny MeSH
- Climate Change MeSH
- Wastewater * MeSH
- Food Chain MeSH
- Fresh Water MeSH
- Aquatic Organisms MeSH
- Animals MeSH
- Check Tag
- Animals MeSH
- Publication type
- Journal Article MeSH
- Names of Substances
- Wastewater * MeSH
We report on the design and performance of a fiber-based, multi-channel laser amplifier seed pulse distribution system. The device is designed to condition and distribute low energy laser pulses from a mode-locked oscillator to multiple, highly synchronized, high energy amplifiers integrated into a laser beamline. Critical functions such as temporal pulse stretching well beyond 100 ps/nm, pulse picking, and fine control over the pulse delay up to 300 ps are all performed in fiber eliminating the need for bulky and expensive grating stretchers, Pockels cells, and delay lines. These functions are characterized and the system as a whole is demonstrated by seeding two high energy amplifiers in the laser beamline. The design of this system allows for complete computer control of all functions, including tuning of dispersion, and is entirely hands-free. The performance of this device and its subsystems will be relevant to those developing lasers where reliability, size, and cost are key concerns in addition to performance; this includes those developing large-scale laser systems similar to ours and also those developing table-top experiments and commercial systems.
- Publication type
- Journal Article MeSH
In this work, a laboratory scaled industrial interconnected nonlinear Multi-Input|Multi-Output (MIMO) three-tank system, was modelled to control the liquid levels. Ensuing the tradition in the process industry to apply linear controller to most control processes, a linear control scheme was developed for this system. However, since linear schemes are proximate to actual process models, they may not be adequate, especially for highly nonlinear systems. Therefore, a nonlinear control scheme was also developed and compared with the linear scheme. Specifically, optimal linear and nonlinear controllers were designed. In summary, the results of the two control schemes showed adequate performance. However, the linear controller had more robust control and required lesser computational demand compared to the nonlinear scheme. To enhance the computational demand of the nonlinear scheme, a third-party MATLAB toolbox, Automatic Control and Dynamic Optimization (ACADO) toolbox, that interfaces MATLAB with C++ to speed up computations was also utilised, and its results compared, and tentatively validate the earlier solved nonlinear control scheme.
- Keywords
- ACADO, Hamilton-Jacobi equation, Linear optimal control, Nonlinear optimal control, Three-tank-system,
- Publication type
- Journal Article MeSH
Cyanobacteria Synechococcus sp. PCC 7942 and Synechocystis sp. PCC 6803 show similar changes in the metabolic response to changed CO2 conditions but exhibit significant differences at the transcriptomic level. This study employs a systems biology approach to investigate the difference in metabolic regulation of Synechococcus sp. PCC 7942 and Synechocystis sp. PCC 6803. Presented multi-level kinetic model for Synechocystis sp. PCC 6803 is a new approach integrating and analysing metabolomic, transcriptomic and fluxomics data obtained under high and ambient CO2 levels. Modelling analysis revealed that higher number of different isozymes in Synechocystis 6803 improves homeostatic stability of several metabolites, especially 3PGA by 275%, against changes in gene expression, compared to Synechococcus sp. PCC 7942. Furthermore, both cyanobacteria have the same amount of phosphoglycerate mutases but Synechocystis 6803 exhibits only ~20% differences in their mRNA levels after shifts from high to ambient CO2 level, in comparison to ~500% differences in the case of Synechococcus sp. PCC 7942. These and other data imply that the biochemical control dominates over transcriptional regulation in Synechocystis 6803 to acclimate central carbon metabolism in the environment of variable inorganic carbon availability without extra cost carried by large changes in the proteome.
- MeSH
- Metabolism MeSH
- Metabolomics MeSH
- Carbon Dioxide metabolism MeSH
- Gene Expression Regulation, Enzymologic * MeSH
- Gene Expression Regulation, Bacterial * MeSH
- Gene Expression Profiling MeSH
- Synechococcus genetics metabolism MeSH
- Synechocystis genetics metabolism MeSH
- Systems Biology MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Names of Substances
- Carbon Dioxide MeSH
Anterior cervical plate fixation is an approved surgical technique for cervical spine stabilization in the presence of anterior cervical instability. Rigid plate design with screws rigidly locked to the plate is widely used and is thought to provide a better fixation for the treated spinal segment than a dynamic design in which the screws may slide when the graft is settling. Recent biomechanical studies showed that dynamic anterior plates provide a better graft loading possibly leading to accelerated spinal fusion with a lower incidence of implant complications. This, however, was investigated in vitro and does not necessarily mean to be the case in vivo, as well. Thus, the two major aspects of this study were to compare the speed of bone fusion and the rate of implant complications using either rigid- or dynamic plates. The study design is prospective, randomized, controlled, and multi-centric, having been approved by respective ethic committees of all participating sites. One hundred and thirty-two patients were included in this study and randomly assigned to one of the two groups, both undergoing routine level-1- or level-2 anterior cervical discectomy with autograft fusion receiving either a dynamic plate with screws being locked in ap - position (ABC, Aesculap, Germany), or a rigid plate (CSLP, Synthes, Switzerland). Segmental mobility and implant complications were compared after 3- and 6 months, respectively. All measurements were performed by an independent radiologist. Mobility results after 6 months were available for 77 patients (43 ABC/34 CSLP). Mean segmental mobility for the ABC group was 1.7 mm at the time of discharge, 1.4 mm after 3 months, and 0.8 mm after 6 months. For the CSLP- group the measurements were 1.0, 1.8, and 1.7 mm, respectively. The differences of mean segmental mobility were statistically significant between both groups after 6 months (P = 0.02). Four patients of the CSLP-group demonstrated surgical hardware complications, whereas no implant complications were observed within the ABC-group (P = 0.0375). Dynamic plate designs provided a faster fusion of the cervical spine compared with rigid plate designs after prior spinal surgery. Moreover, the rate of implant complications was lower within the group of patients receiving a dynamic plate. These interim results refer to a follow-up period of 6 months after prior spinal surgery. Further investigations will be performed 2 years postoperatively.
- MeSH
- Spinal Fusion methods MeSH
- Bone Plates * MeSH
- Cervical Vertebrae diagnostic imaging pathology MeSH
- Middle Aged MeSH
- Humans MeSH
- Treatment Failure MeSH
- Prospective Studies MeSH
- Radiography MeSH
- Case-Control Studies MeSH
- Check Tag
- Middle Aged MeSH
- Humans MeSH
- Male MeSH
- Female MeSH
- Publication type
- Journal Article MeSH
- Multicenter Study MeSH
- Randomized Controlled Trial MeSH
The aim of this study was to describe the clinical and sonographic features of ovarian metastases originating from colorectal cancer (mCRC), and to discriminate mCRC from primary ovarian cancer (OC). We conducted a multi-institutional, retrospective study of consecutive patients with ovarian mCRC who had undergone ultrasound examination using the International Ovarian Tumor Analysis (IOTA) terminology, with the addition of evaluating signs of necrosis and abdominal staging. A control group included patients with primary OC. Clinical and ultrasound data, subjective assessment (SA), and an assessment of different neoplasias in the adnexa (ADNEX) model were evaluated. Fisher's exact and Student's t-tests, the area under the receiver-operating characteristic curve (AUC), and classification and regression trees (CART) were used to conduct statistical analyses. In total, 162 patients (81 with OC and 81 with ovarian mCRC) were included. None of the patients with OC had undergone chemotherapy for CRC in the past, compared with 40% of patients with ovarian mCRC (p < 0.001). The ovarian mCRC tumors were significantly larger, a necrosis sign was more frequently present, and tumors had an irregular wall or were fixed less frequently; ascites, omental cake, and carcinomatosis were less common in mCRC than in primary OC. In a subgroup of patients with ovarian mCRC who had not undergone treatment for CRC in anamnesis, tumors were larger, and had fewer papillations and more locules compared with primary OC. The highest AUC for the discrimination of ovarian mCRC from primary OC was for CART (0.768), followed by SA (0.735) and ADNEX calculated with CA-125 (0.680). Ovarian mCRC and primary OC can be distinguished based on patient anamnesis, ultrasound pattern recognition, a proposed decision tree model, and an ADNEX model with CA-125 levels.
- Keywords
- cancer, colon, metastasic, model, neoplasm, ovary, risk prediction, ultrasound,
- Publication type
- Journal Article MeSH
OBJECTIVES: Mulberry-like changes of the posterior inferior nasal turbinate (MPINT) can lead to nasal obstruction. Extraesophageal reflux (EER) characterized by lower pH causes mucosal inflammation and therefore can contribute to sinonasal pathologies. No prior studies have objectively examined the possible association between acidic pH and MPINT formation. Therefore, this study is aimed to investigate the 24-h pharyngeal pH value in patients with MPINT. STUDY DESIGN: Prospective case-control multi-center study. METHODS: Fifty-five patients with chronic EER symptoms were included in the study. They filled in questionnaires aimed at reflux and sinonasal symptoms (RSI®, SNOT-22) and underwent video endoscopy evaluating the laryngeal findings (RFS®) and the presence or absence of the MPINT. And, 24-h oropharyngeal pH monitoring was used to detect the acidic pH environment in the pharynx. RESULTS: Out of the 55 analyzed patients, 38 had the MPINT (group 1), and in 17 patients, the MPINT was absent (group 2). Based on the pathological RYAN Score, in 29 (52.7%) patients, severe acidic pH drops were detected. In group 1, the acidic pH drops were diagnosed significantly more often (68.4%) compared with those in group 2 (p = 0.001). Moreover, in group 1, a significantly higher median total percentage of time spent below pH 5.5 (p = 0.005), as well as a higher median number of events lasting more than 5 min (p = 0.006), and higher median total number of events with pH drops (p = 0.017) were observed. CONCLUSION: In this study, the MPINT was significantly more often present in patients with acidic pH events detected by 24-h oropharyngeal pH monitoring. Acidic pH in the pharynx might lead to MPINT formation. LEVEL OF EVIDENCE: 3 Laryngoscope, 134:62-68, 2024.
- Keywords
- 24-h oropharyngeal pH monitoring, acidic pharyngeal pH, mulberry posterior inferior nasal turbinate, nasal obstruction, nasal video endoscopy,
- MeSH
- Pharynx MeSH
- Gastroesophageal Reflux * diagnosis MeSH
- Hydrogen-Ion Concentration MeSH
- Humans MeSH
- Turbinates MeSH
- Prospective Studies MeSH
- Case-Control Studies MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
- Multicenter Study MeSH
- Research Support, Non-U.S. Gov't MeSH
BACKGROUND: Patients suffering from functional neurological disorder (FND) experience disabling neurological symptoms not caused by an underlying classical neurological disease (such as stroke or multiple sclerosis). The diagnosis is made based on reliable positive clinical signs, but clinicians often require additional time- and cost consuming medical tests and examinations. Resting-state functional connectivity (RS FC) showed its potential as an imaging-based adjunctive biomarker to help distinguish patients from healthy controls and could represent a "rule-in" procedure to assist in the diagnostic process. However, the use of RS FC depends on its applicability in a multi-centre setting, which is particularly susceptible to inter-scanner variability. The aim of this study was to test the robustness of a classification approach based on RS FC in a multi-centre setting. METHODS: This study aimed to distinguish 86 FND patients from 86 healthy controls acquired in four different centres using a multivariate machine learning approach based on whole-brain resting-state functional connectivity. First, previously published results were replicated in each centre individually (intra-centre cross-validation) and its robustness across inter-scanner variability was assessed by pooling all the data (pooled cross-validation). Second, we evaluated the generalizability of the method by using data from each centre once as a test set, and the data from the remaining centres as a training set (inter-centre cross-validation). RESULTS: FND patients were successfully distinguished from healthy controls in the replication step (accuracy of 74%) as well as in each individual additional centre (accuracies of 73%, 71% and 70%). The pooled cross validation confirmed that the classifier was robust with an accuracy of 72%. The results survived post-hoc adjustment for anxiety, depression, psychotropic medication intake, and symptom severity. The most discriminant features involved the angular- and supramarginal gyri, sensorimotor cortex, cingular- and insular cortex, and hippocampal regions. The inter-centre validation step did not exceed chance level (accuracy below 50%). CONCLUSIONS: The results demonstrate the applicability of RS FC to correctly distinguish FND patients from healthy controls in different centres and its robustness against inter-scanner variability. In order to generalize its use across different centres and aim for clinical application, future studies should work towards optimization of acquisition parameters and include neurological and psychiatric control groups presenting with similar symptoms.
- Keywords
- Biomarker, Conversion disorder, Functional connectivity, Inter-scanner variability, Multi-site,
- MeSH
- Conversion Disorder * diagnostic imaging physiopathology MeSH
- Humans MeSH
- Magnetic Resonance Imaging * methods MeSH
- Brain * diagnostic imaging physiopathology MeSH
- Reproducibility of Results MeSH
- Case-Control Studies MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
- Multicenter Study MeSH
- Research Support, Non-U.S. Gov't MeSH