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We discuss some of our work on averages along polynomial sequences in nilpotent groups of step 2. Our main results include boundedness of associated maximal functions and singular integrals operators, an almost everywhere pointwise convergence theorem for ergodic averages along polynomial sequences, and a nilpotent Waring theorem. Our proofs are based on analytical tools, such as a nilpotent Weyl inequality, and on complex almost-orthogonality arguments that are designed to replace Fourier transform tools, which are not available in the noncommutative nilpotent setting. In particular, we present what we call a nilpotent circle method that allows us to adapt some of the ideas of the classical circle method to the setting of nilpotent groups.

Attila Magyar,1,2 Martin Wagner,2–4 Phillip Thomas,1,2 Carolin Malsch,2 Reinhard Schneider,3 Stefan Störk,4,5 Peter U Heuschmann,2,4,6 Rainer G Leyh,1 Mehmet Oezkur1,21Department of Cardiovascular Surgery, University Hospital Würzburg, Würzburg, Germany; 2Institute of Clinical Epidemiology and Biometry, University of Würzburg, Würzburg, Germany; 3Division of Nephrology, Department of Medicine I, University Hospital Würzburg, Würzburg, Germany; 4Comprehensive Heart Failure Center, University of Würzburg, Würzburg, Germany; 5Division of Cardiology, Department of Medicine I, University Hospital Würzburg, Würzburg, Germany; 6Clinical Trial Center Würzburg, University Hospital Würzburg, Würzburg, Germany Background: Acute kidney injury (AKI) is a serious complication after cardiac surgery that is associated with increased mortality and morbidity. Heme oxygenase-1 (HO-1) is an enzyme synthesized in renal tubular cells as one of the most intense responses to oxidant stress linked with protective, anti-inflammatory properties. Yet, it is unknown if serum HO-1 induction following cardiac surgical procedure involving cardiopulmonary bypass (CPB) is associated with incidence and severity of AKI. Patients and methods: In the present study, we used data from a prospective cohort study of 150 adult cardiac surgical patients. HO-1 measurements were performed before, immediately after and 24 hours post-CPB. In univariate and multivariate analyses, the association between HO-1 and AKI was investigated. Results: AKI with an incidence of 23.3% (35 patients) was not associated with an early elevation of HO-1 after CPB in all patients (P=0.88), whereas patients suffering from AKI developed a second burst of HO-1 24 hours after CBP. In patients without AKI, the HO-1 concentrations dropped to baseline values (P=0.031). Furthermore, early HO-1 induction was associated with CPB time (P=0.046), while the ones 24 hours later lost this association (P=0.219). Conclusion: The association of the second HO-1 burst 24 hours after CBP might help to distinguish between the causality of AKI in patients undergoing CBP, thus helping to adapt patient stratification and management. Keywords: acute kidney injury, cardiac surgery, heme oxygenase-1, cardiopulmonary bypass

ContextAdipose steroid metabolism modifies body fat development in polycystic ovary syndrome (PCOS).ObjectiveTo determine whether subcutaneous (SC) abdominal adipose aldo-keto reductase 1C3 (AKR1C3; a marker of testosterone generation) is increased in normal-weight women with PCOS vs age- and body mass index (BMI)-matched normoandrogenic ovulatory women (controls) and is related to SC abdominal adipose activator protein-1 (AP-1; a marker of adipocyte differentiation) and/or androgen receptor (AR) protein expression in predicting fat accretion.DesignProspective cohort study.SettingAcademic center.PatientsEighteen normal-weight PCOS women; 17 age- and BMI-matched controls.InterventionsCirculating hormone/metabolic determinations, intravenous glucose tolerance testing, total body dual-energy x-ray absorptiometry, SC abdominal fat biopsy, immunohistochemistry.Main outcome measuresClinical characteristics, hormonal concentrations, body fat distribution, SC adipose AKR1C3, AR, and AP-1 protein expression.ResultsWomen with PCOS had significantly higher serum androgen levels and greater android/gynoid fat mass ratios than controls. SC adipose AKR1C3, AR, and AP-1 protein expressions were comparable between the study groups, but groups differed in correlations. In PCOS women vs controls, SC adipose AKR1C3 protein expression correlated positively with android and gynoid fat masses and negatively with SC adipose AP-1 protein expression. SC adipose AR protein expression correlated negatively with fasting serum free fatty acid and high-density lipoprotein levels. In both study groups, SC adipose AKR1C3 protein expression negatively correlated with serum cortisol levels.ConclusionIn normal-weight PCOS women, SC abdominal adipose AKR1C3 protein expression, in combination with intra-adipose AP-1 and AR-dependent events, predicts fat accretion in the presence of physiological cortisol levels.

This study reveals the findings of an online questionnaire survey, carried out in Jászság micro region in Hungary, to gain insights into the motivation patterns and attitudes of teachers of the region (N=70) with regard to the creation and development of a virtual professional social forum. We highlighted the participant teachers’ beliefs and opinions on an online course to be developed within the framework of higher education. One of major results is that the respondents welcome a virtual forum for Jászság teachers both in online and offline format. Jászság region, beliefs on online courses, digital competency

A series of pentasubstituted 4H-pyrans and tetrahydrobenzo[b]pyrans are synthesized with excellent yields via a one-pot condensation of aromatic aldehydes, malononitrile, and a dicarbonyl compound, ethyl acetoacetate, acetyl-acetone or dimedone, in the presence of 4 Å molecular sieve modified with zinc(II) as heterogeneous catalyst, in ethanol. The process offers numerous advantages, such as better yield, short reaction time, and mild reaction conditions. The catalyst’s preparation is simple and it could be reused while still maintaining its activity.

The low bioavailability of most phytochemicals limits their anticancer effects in humans. The present study was designed to test whether combining arctigenin (Arc), a lignan mainly from the seed of Arctium lappa, with green tea (GT) and quercetin (Q) enhances the chemopreventive effect on prostate cancer. We performed in vitro proliferation studies on different cell lines. We observed a strong synergistic anti-proliferative effect of GT+Q+Arc in exposing androgen-sensitive human prostate cancer LNCaP cells. The pre-malignant WPE1-NA22 cell line was more sensitive to this combination. No cytotoxicity was observed in normal prostate epithelial PrEC cells. For an in vivo study, 3-week-old, prostate-specific PTEN (phosphatase and tensin homolog) knockout mice were treated with GT+Q, Arc, GT+Q+Arc, or the control daily until 16 weeks of age. In vivo imaging using prostate-specific membrane antigen (PSMA) probes demonstrated that the prostate tumorigenesis was significantly inhibited by 40% (GT+Q), 60% (Arc at 30 mg/kg bw), and 90% (GT+Q+Arc) compared to the control. A pathological examination showed that all control mice developed invasive prostate adenocarcinoma. In contrast, the primary lesion in the GT+Q and Arc alone groups was high-grade prostatic intraepithelial neoplasia (PIN), with low-grade PIN in the GT+Q+Arc group. The combined effect of GT+Q+Arc was associated with an increased inhibition of the androgen receptor, the PI3K/Akt pathway, Ki67 expression, and angiogenesis. This study demonstrates that combining Arc with GT and Q was highly effective in prostate cancer chemoprevention. These results warrant clinical trials to confirm the efficacy of this combination in humans.

The cost optimal scheduling of a household refrigerator is presented in this work. The fundamental approach is the model predictive control methodology applied to the piecewise affine model of the refrigerator.

A current source inverter model has been developed in the given paper that is constructed from six LTI models for the different switching modes. The overall model is in a piecewise affine form that supports the use of model predictive control. The model has been verified against engineering expectations and its open-loop performance shows that it is a promising basis of model predictive control structures.

We present Golden Gate, an FPGA-based simulation tool that decouples the timing of an FPGA host platform from that of the target RTL design. In contrast to previous work in static time-multiplexing of FPGA resources, Golden Gate employs the Latency-Insensitive Bounded Dataflow Network (LI-BDN) formalism to decompose the simulator into subcomponents, each of which may be independently and automatically optimized. This structure allows Golden Gate to support a broad class of optimizations that improve resource utilization by implementing FPGA-hostile structures over multiple cycles, while the LI-BDN formalism ensures that the simulator still produces bit- and cycle-exact results. To verify that these optimizations are implemented correctly, we also present LIME, a model-checking tool that provides a push-button flow for checking whether optimized subcomponents adhere to an associated correctness specification, while also guaranteeing forward progress. Finally, we use Golden Gate to generate a cycle-exact simulator of a multi-core SoC, where we reduce LUT utilization by up to 26% by coercing multi-ported, combinationally read memories into simulation models backed by time-multiplexed block RAMs, enabling us to simulate 50% more cores on a single FPGA.

Plasma cell-free DNA (cfDNA) is a noninvasive biomarker for cell death of all organs. Deciphering the tissue origin of cfDNA can reveal abnormal cell death because of diseases, which has great clinical potential in disease detection and monitoring. Despite the great promise, the sensitive and accurate quantification of tissue-derived cfDNA remains challenging to existing methods due to the limited characterization of tissue methylation and the reliance on unsupervised methods. To fully exploit the clinical potential of tissue-derived cfDNA, here we present one of the largest comprehensive and high-resolution methylation atlas based on 521 noncancer tissue samples spanning 29 major types of human tissues. We systematically identified fragment-level tissue-specific methylation patterns and extensively validated them in orthogonal datasets. Based on the rich tissue methylation atlas, we develop the first supervised tissue deconvolution approach, a deep-learning-powered model, cfSort, for sensitive and accurate tissue deconvolution in cfDNA. On the benchmarking data, cfSort showed superior sensitivity and accuracy compared to the existing methods. We further demonstrated the clinical utilities of cfSort with two potential applications: aiding disease diagnosis and monitoring treatment side effects. The tissue-derived cfDNA fraction estimated from cfSort reflected the clinical outcomes of the patients. In summary, the tissue methylation atlas and cfSort enhanced the performance of tissue deconvolution in cfDNA, thus facilitating cfDNA-based disease detection and longitudinal treatment monitoring.

This paper discusses the regimes of Jarosław Kaczyński in Poland (2015–) and Viktor Orbán in Hungary (2010–) from the perspective of a curious paradox: they are very different in functioning but adhere to right-wing ideological frames that are very similar. First, we argue for a dual-level approach to understanding the formal and informal nature of these regimes, and we identify Poland as a conservative autocratic attempt and Hungary as an established patronal autocracy. After a comparative analysis of the two systems, we analyze the regimes’ common ideological frames and explain how legitimacy panels fit the purposes of an ideology-driven regime (Poland) and an ideology-applying one (Hungary). Finally, the analysis is used to explain the divergent responses of the Polish and the Hungarian regimes to the 2022 Russian invasion of Ukraine, which also brought the mutual relations of the two de-democratizing countries in the European Union to a breaking point.

The aims of the study were (1) to develop a domain-general computer-based assessment tool for inductive reasoning and to empirically test the theoretical models of Klauer and Christou and Papageorgiou; and (2) to develop an online game to foster inductive reasoning through mathematical content and to investigate its effectiveness. The sample was drawn from fifth-grade students for the assessment (N = 267) along with the intervention study (N = 122). The online figurative test consisted of 54 items: nine items were developed for each of the six inductive reasoning processes. The digital game-based training program included 120 learning tasks embedded in mathematical content with differential feedback and instructional support. The test had good psychometric properties regarding reliabilities, means, and standard deviations. Confirmatory factor analyses revealed that the six processes of inductive reasoning and the three latent factors of Similarity, Dissimilarity, and Integration could be empirically confirmed. The training program was effective in general (corrected effect size = 0.38); however, the process of cross-classification was not developed significantly. Findings could contribute to a more detailed understanding of the structure and the modifiability of inductive reasoning processes and could reveal further insights into the nature of fluid intelligence.

Study region: Pannonian Basin, Hungary, Maros fluvial fan. Study focus: This paper presents a novel approach to characterise a distal lobe of a fluvial fan, demonstrating how a combined interpretation of high-resolution geophysical methods like electrical resistivity tomography and geophysical cone penetration tests together with log-correlation, hydrogeochemical, isotope and noble gas data provides a sound basis for aquifer characterisation. This multidisciplinary investigative approach is applicable to any fluvial fan to support water management. New hydrological insights for the region: (1) The studied fluvial fan forms a hydraulically interconnected aquifer system, with three channel belts and six hydrostratigraphic units. (2) Mean groundwater residence times are distinct in the aquifers studied. Holocene infiltration, with apparent residence time younger than 20–22 years is characteristic in the uppermost channel belt and forms part of local groundwater flow systems. The deeper aquifers host groundwater infiltrated during the Pleistocene, as part of the intermediate flow system. (3) Where the silty-clayey floodplain sediments have been replaced by sandy deposits, and groundwater abstraction is present, groundwater can communicate between the upper and lower channel belts, therefore fresh infiltration passes into the deeper channel belts, resulting mostly in mean residence times younger than 100 years. However, Pleistocene infiltration was detected at about 30 m below surface in the second channel belt, where the unconfined aquifer is missing and silty-clayey sediments are on the surface.