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We present a unified framework for deriving PAC-Bayesian generalization bounds. Unlike most previous literature on this topic, our bounds are anytime-valid (i.e., time-uniform), meaning that they hold at all stopping times, not only for a fixed sample size. Our approach combines four tools in the following order: (a) nonnegative supermartingales or reverse submartingales, (b) the method of mixtures, (c) the Donsker-Varadhan formula (or other convex duality principles), and (d) Ville's inequality. Our main result is a PAC-Bayes theorem which holds for a wide class of discrete stochastic processes. We show how this result implies time-uniform versions of well-known classical PAC-Bayes bounds, such as those of Seeger, McAllester, Maurer, and Catoni, in addition to many recent bounds. We also present several novel bounds. Our framework also enables us to relax traditional assumptions; in particular, we consider nonstationary loss functions and non-i.i.d. data. In sum, we unify the derivation of past bounds and ease the search for future bounds: one may simply check if our supermartingale or submartingale conditions are met and, if so, be guaranteed a (time-uniform) PAC-Bayes bound. [ABSTRACT FROM AUTHOR]

A groove gap waveguide (GGW) leaky wave antenna with a wide scan angle in the terahertz (THz) band (430–560 GHz) is presented in this study. The unnecessary tight contact between the top plate and pins of the GGW makes it easy for the fine fabrication and assembly of this THz antenna. Scanning of pointing directions with frequency, together with the low side‐lobe level (SLL), is designed for the pins' heights and intervals as well as the groove cavity width. Measurement results of S11 parameters remain about −20 dB, besides, the antenna scan angle range is 15o within 430–560 GHz, and the gains are also above 15 dB within that working frequency bands. [ABSTRACT FROM AUTHOR]

In his interpretation of Nietzsche, Heidegger on the one hand acknowledges the anti‑metaphysical orientation of Nietzsche’s nihilism, but on the other hand considers Nietzsche to be the ultimate metaphysician. This asses‑ sement is based firstly on Heidegger’s reflections on the relationship between metaphysics and nihilism. By revealing the origin and end of metaphysics, it is to be shown that nihilism and metaphysics are two aspects of the same thing. Moreover, Heidegger expands the meaning of metaphysics by ascribing to it the distinction between the sensuous and supersensuous worlds, between beings and beingness. Based on the critique of Nietzsche, he is able to develop a post‑metaphysical philosophical conception. Nietzsche himself, however, has not fallen into metaphysics, and in his overcoming of metaphysics and his vision of post‑metaphysical thinking he is rather a precursor of Heid [ABSTRACT FROM AUTHOR]

A novel serrated ground plane (NSGP) for na low-loss reflectarray antenna is presented in this paper. Compared with a conventional smooth ground plane (CGP), the NSGP consists of a series of serrated elements, which can reflect the incident waves in the main beam direction, so the losses of the reflectarray can be effectively reduced. The principle and losses of reflectarray antennas are studied and analyzed. Then, a low-loss NSGP is proposed, and two design methods for the NSGP are given in this paper. Finally, a reflectarray antenna with elements arranged in a 15×15 grid is designed, simulated and measured with the NSGP and CGP respectively within the frequency from 12.88 to 13.88GHz. The results show that the reflectarray antenna with the NSGP can effectively utilize the reflected waves and has a maximum higher gain of 0.681 dB compared with the gain of the reflectarray with the CGP. This NSGP has a potential to be used in the high accurate design of the reflectarray which requires to realize beam forming, low-loss, high-efficiency, etc. [ABSTRACT FROM AUTHOR]

From the hermeneutics of facticity to phenomenological destruction, Heidegger's constant effort has been to achieve a non-metaphysical, pre-theoretical methodology of philosophy. His ideas finally lead to the development of the method of formal indication. In this essay, I will consider first the methodological function of historical things, in order to illustrate the method of destruction. Then, I will explain the definition of philosophy from the point of view of formal indication, thereby showing how different this method is from traditional philosophical methods. Finally, I will analyse the importance of this transformation of methodology, in order to reveal in which sense a concrete universality is possible and how it contributes to the foundation of the ontology of life. [ABSTRACT FROM AUTHOR]

In gastric carcinoma, the nuclear factor-B (NF-B) signaling pathway is highly active, and the constitutive activation of NF-B prompts malignant cell proliferation. MicroRNAs are considered to be important mediators in the regulation of the NF-B signaling pathway. The present study predominantly focussed on the effects of microRNA (miR)-19a on NF-B activation. Reverse transcription-quantitative polymerase chain reaction was used to quantify the relative levels of miR-19a in gastric carcinoma cells. MTT assays were used to determine the effect of miR-19a on cellular proliferation. To detect the activation of NF-B, western blotting was performed to measure the protein levels of NF-B and the products of its downstream target genes. To define the target genes, luciferase reporter assays were used. miR-19a was found to be markedly upregulated in gastric carcinoma cells. The overexpression of miR-19a resulted in proliferation and enhanced migratory capabilities of the MGC-803 gastric carcinoma cell line. The results of the western blot analysis demonstrated that the protein levels of p65 increased when the MGC-803 cells were transfected with miR-19a mimics. In addition, the downstream target genes of miR-19a, including intercellular adhesion molecule, vascular cell adhesion molecule and monocyte chemoattractant protein-1, were upregulated. The results of the luciferase assay indicated that IB-a was the target gene of miR-19a. Therefore, the results of the present study suggested that miR-19a enhances malignant gastric cell proliferation by constitutively activating the NF-B signaling pathway. [ABSTRACT FROM AUTHOR]

Considering the case of ASV (autonomous surface vehicle) navigating with low speed near water surface, a new method for design of roll motion controller is proposed in order to restrainwave disturbance effectively and improve roll stabilizing performance. Control system design is based on GPC (general predictive control) theory and working principle of zero-speed fin stabilizer. Coupling horizontal motion model of ASV is decoupled, and an equivalent transfer function of roll motion is obtained and transformed into a discrete difference equation through inverse Laplace transformation and Euler approximation. Finally, predictive model of GPC, namely, the difference equation of roll motion, is given. GPC algorithm of ASV roll motion is derived from performance index based on roll stabilizing performance and energy consumption used for driving fin stabilizer. In allusion to time-variant parameters in roll motion model, recursive least square method is adopted for parameter estimation. Simulation results of ASV roll motion control show better stabilizing performance and minimized energy consumption improved by self-adaptive GPC. [ABSTRACT FROM AUTHOR]

This work proposes an improved unscented Kalman filter (UKF)-based simultaneous localization andmapping (SLAM) algorithm based on an adaptive unscented Kalman filter (AUKF) with a noise statistic estimator. The algorithm solves the issue that conventional UKF-SLAMalgorithms have declining accuracy, with divergence occurring when the prior noise statistic is unknown and time-varying. The new SLAM algorithm performs an online estimation of the statistical parameters of unknown system noise by introducing a modified Sage-Husa noise statistic estimator. The algorithm also judges whether the filter is divergent and restrains potential filtering divergence using a covariance matchingmethod. This approach reduces state estimation error, effectively improving navigation accuracy of the SLAM system. A line feature extraction is implemented through a Hough transform based on the ranging sonar model. Test results based on unmanned underwater vehicle (UUV) sea trial data indicate that the proposed AUKF-SLAM algorithm is valid and feasible and provides better accuracy than the standard UKF-SLAM system. [ABSTRACT FROM AUTHOR]

Two layers of buried optical waveguides are manufactured in silicate glass substrate. Using ion-exchange process, this procedure is composed of two successive cycles of buried waveguide fabrication. Characterizations of these waveguides show that the two layers have similar dimensions for both waveguide core and for mode field, and thus similar optical properties. Loss analysis indicates that coupling loss of top and bottom layer waveguide with single-mode-fiber being 0.80 dB/facet and 0.75 dB/facet, respectively. [ABSTRACT FROM AUTHOR]

A Potter horn and a compact orthomode transducer operating at 150 GHz are designed using full wave analysis. The Potter horn patterns have good symmetry within the main beam, the sidelobe level is less than -35 dB, and the cross-polarization level reaches 21 dB. The transmission test results of the orthomode transducer and feed horn show that the bandwidth (S11<-20\ dB) is 16 GHz. The whole dimension is only (25\ mm\times 20\ mm\times 70\ mm), whereas the orthomode transducer dimension is (25\ mm\times 20\ mm\times 30\ mm). [ABSTRACT FROM PUBLISHER]

This paper primarily concerns the effective coordination of the procedures and methods employed in open pit mining operations under the background of river management. The central objective of this study is to identify a viable approach for ensuring rational and efficient development of open pit mineral resources while simultaneously protecting and restoring the ecological environment of the river. This approach should facilitate the realization of a harmonious symbiosis between mining and river management. The intricate mutual influence relationship between river management and open pit mining is first analyzed in depth, which provides a solid foundation for the subsequent coordination strategy development. In light of the aforementioned considerations, a set of coordination procedures for open pit mining based on river management conditions is proposed. These procedures emphasize the integration of river protection into the overall layout of mining at the planning stage. The implementation of scientific mining schemes, accompanied by rigorous control of the scope and depth of mining operations has proven to be an effective means of reducing the impact of mining activities on river environments. This approach has also facilitated the achievement of a balance and coordination between mining and river management. [ABSTRACT FROM AUTHOR]

Antiaromaticity is extended from aromaticity as a complement to describe the unsaturated cyclic molecules with antiaromatic destabilization. To prepare antiaromatic species is a particularly challenging goal in synthetic chemistry because of the thermodynamic instability of such molecules. Among that, both Hückel and Möbius antiaromatic species have been reported, whereas the Craig one has not been realized to date. Here, we report the first example of planar Craig antiaromatic species. Eight Craig antiaromatic compounds were synthesized by deprotonation-induced reduction process and were fully characterized as follows. Single-crystal X-ray crystallography showed that these complexes have planar structures composed of fused five-membered rings with clearly alternating carbon--carbon bond lengths. In addition, spectroscopy in these structures showed distinctive upfield shifts of the proton peaks to the range of antiaromatic peripheral hydrogens. Experimental spectroscopy observations, along with density-functional theory (DFT) calculations, provided evidence for the Craig antiaromaticity of these complexes. Further study experimentally and theoretically revealed that the strong exothermicity of the acid-base neutralization process was the driving force for this challenging transformation forming Craig antiaromatic species. Our findings complete a full cycle of aromatic chemistry, opening an avenue for the development of new class of antiaromatic systems. [ABSTRACT FROM AUTHOR]

Due to the Joule heating effect induced by the use of an assisting electric field, glass wafer temperature is experimentally found to increase synchronically with the flow of current during the process of field-assisted ion diffusion. A theoretical analysis demonstrates that the amplitude of the glass wafer temperature increase is dictated by competition between two factors, heat generation and heat dissipation. Heat generation and heat dissipation both become stronger as the glass wafer temperature increases. Studies have shown that the Joule heating effect can influence the waveguide manufacturing process profoundly, including aspects such as the stability of ion diffusion, theoretical modeling of the ion-diffusion process, and waveguide depth uniformity over the glass wafer. [ABSTRACT FROM AUTHOR]

Cerebral venous sinus thrombosis (CVST) is a rare and devastating complication of inflammatory bowel disease (IBD). Early diagnosis and prompt treatment could improve prognosis. The aim of our study was to investigate the clinical data and predictive factors of inflammatory bowel disease in patients with a diagnosis of CVST. All IBD patient data were collected from July 2013 and September 2020. Clinical data, predictive factors and prognosis were compared between IBD patients with CVST and the IBD control group. The incidence of CVST in our study was 0.48%. The mean age of IBD patients with CVST was 34.9 years. The average duration of IBD was 4 years when cerebrovascular events occurred. The clinical presentation of CVST included headache (73.1%), vomiting (30.8%), limb dysmetria (26.9%), speech impairment (11.5%), blurred vision (7.7%), epileptic seizures (7.7%) and drowsiness (3.8%). The most common location for CVST was the transverse sinus (61.5%) followed by the superior sagittal sinus (30.8%). Anaemia, low albumin and elevated d-dimer were independent predictors of CVST in patients with IBD. Anticoagulation therapy was effective. The prognosis of IBD patients with CVST was worse than that of IBD patients without CVST. Early identification of the risk and clinical features of CVST in IBD patients is important. Prompt antithrombotic therapy is a safe and effective treatment. [ABSTRACT FROM AUTHOR]

Objective and Methods: To analyze the association between global DNA methylation and single-nucleotide polymorphisms (SNPs) in methylenetetrahydrofolate reductase (MTHFR). MTHFR polymorphisms rs1801133 and rs1801131 were detected using the restriction fragment length polymorphism method, and cytokinesis-block micronucleus (MN) frequency and global DNA methylation was measured in workers from 410 shoe factories. Results: A multilinear regression analysis demonstrated that DNA methylation of the TT variant allele of rs1801133 was lower than that of the CC wild type allele (Exp(β) [95% CI], 0.76 [0.56, 1.02], P = 0.071), with a P-value approaching significance. A significantly increased MN frequency was observed for carriers of the TT genotype (frequency ratio = 1.27, 95% CI: 1.07-1.51, P < 0.01). Conclusion: The results imply that the TT genotype in rs1801133 is associated with global DNA hypomethylation, which may influence the induction of MN following exposure to benzene. [ABSTRACT FROM AUTHOR]

Magnetic nanofiber has been widely applied in biomedical fields due to its distinctive size, morphology, and properties. We proposed a novel needleless electrospinning method to prepare magnetic nanofibers from the self-assembling "Taylor cones" of poly(vinyl pyrrolidone) (PVP)/Fe3O4 ferrofluid (PFF) under the coincident magnetic and electric fields. The results demonstrated that a static PFF Rosensweig instability with a conical protrusion could be obtained under the magnetic field. The tip of the protrusion emitted an electrospinning jet under the coincident magnetic and electric fields. The needleless electrospinning showed a similar process phenomenon in comparison with conventional electrospinning. The prepared nanofibers were composed of Fe3O4 particles and PVP polymer. The Fe3O4 particles aggregated inside and on the surface of the nanofibers. The nanofibers prepared by needleless electrospinning exhibited similar morphology compared with the conventionally electrospun nanofibers. The nanofibers also exhibited good ferromagnetic and magnetic field responsive properties. [ABSTRACT FROM AUTHOR]

Background: The clinical phenotype of both hypertrophic cardiomyopathy (HCM) and left ventricular hypertrophy (LVH) induced by hypertension is heterogeneous. Genetic factors may contribute to this heterogeneity. Evidence is accumulating that the peroxisome proliferator-activated receptor-γ coactivator-1α ( PGC-1α) gene plays a role in cardiac hypertrophy. The aim of our study was to identify the association between PGC-1α gene polymorphisms and cardiac hypertrophy. Methods: A total of 270 consecutive HCM patients and 2486 hypertensive patients, comprising 1180 with LVH and 1306 without LVH, as well as 894 healthy controls, were successfully investigated. Polymorphisms of the PGC-1α gene were genotyped by PCR-restriction fragment length polymorphism and confirmed by sequencing. Results: The Ser482 allele (rs8192678 G>A and A>A) and CC genotype of Thr394Thr (rs2970847) conferred increased risk for HCM [odds ratio (OR) 1.52, 95% confidence interval (CI) 1.11–2.11; OR 1.49, 95% CI 1.15–1.98, respectively]. The maximum ventricular thickness was greater in HCM patients carrying the Ser482 risk allele than in carriers of the non-risk allele (20.7±4.1 vs. 19.1±4.3 mm, p<0.05) and for the CC Thr394Thr genotype (20.9±4.6 vs. 19.0±4.2 mm, p<0.05). No association was found between PGC-1α polymorphism and hypertension with or without LVH. Conclusions: Our data indicate that variants of the PGC-1α gene are correlated with increased risk for HCM. Clin Chem Lab Med 2007;45:962–7. [ABSTRACT FROM AUTHOR]

Nanostructured Ti/Al multilayers with individual layer thicknesses of 10 nm and 100 nm were fabricated using a direct current magnetron sputtering system. The results showed that the Ti/Al multilayer with λ  =  10 nm exhibited ultra-high specific strength of 658.9 kN · m kg−1, greater than that with λ  =  100 nm and other existing multilayers. Such high specific strength of the Ti/Al multilayers endows them with strong potential for aerospace application. Moreover, depending on the stress concentration and barrier strength of the interface, layers of multilayer with λ  =  10 nm buckled severely, accompanied by the occurrence of pop-in, while a localized shear band formed in the multilayer with λ  =  100 nm. We also found that the occurrence of layer buckling had an effect on the hardness trend. [ABSTRACT FROM AUTHOR]