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In this paper, the relationships between Lie symmetry groups and fundamental solutions for a class of conformable time fractional partial differential equations (PDEs) with variable coefficients are investigated. Specifically, the group-invariant solutions to the considered equations are constructed applying symmetry group method and the corresponding fundamental solutions for these systems are established with the help of the above obtained group-invariant solutions and inverting Laplace transformation. In addition, the connections between fundamental solutions for two conformable time fractional systems are given by equivalence transformation. Furthermore, the conservation laws of these fractional systems are provided using new Noether theorem and obtained Lie algebras.

Background Previous reports have described hypogonadism associated with virus infection such as hantavirus, human immunodeficiency virus (HIV) or severe acute respiratory syndrome coronavirus 2 (SARS-COV-2). However, to our best knowledge there has been no case report of secondary hypogonadism following hand, foot, and mouth disease (HFMD). Case presentation A previously healthy 28-year-old man with no history of major physical and psychological trauma, presented with bilateral gynecomastia and erectile dysfunction 2 weeks after HFMD. Laboratory testament showed the level of gonadotropin hormones declined. Imaging examination demonstrated no major abnormal change in pituitary or reproductive system. The diagnosis of hypogonadism was established. Then the patient was ordered to maintain mental health outward of hospital without drug intervention. One month after presentation, his gonadotropin hormone level and sexual desire had recovered, while bilateral gynecomastia and erectile dysfunction symptoms disappeared. Conclusions Physicians should notice the possibility for hypogonadism in adult patients with a recent history of HFMD.

Following preventive behaviors is a key measure to protect people from infectious diseases. Protection motivation theory (PMT) suggests that perceived risk motivates individuals to take protective measures. The COVID-19 pandemic has posed unprecedented stress to the public, and changes in perceived risk may be more pronounced among college students than among other groups due to the related campus lockdown. With 1,119 college students recruited as research subjects, a quantitative research was conducted in Wuhan, China, to deduce the relationship between the perceived risk and preventive behavior of college students, as well as between the mediation effect of individual affect and the moderating effect of physical exercise. The results showed that the preventive behavior of college students was significantly affected by perceived risk, and both positive affect and negative affect played a mediating role between perceived risk and preventive behavior. Specifically, positive affect aided the relationship between perceived risk and preventive behavior, negative affect was detrimental to their relationship, and the mediation effect of positive affect is significantly higher than that of negative affect. Furthermore, physical exercise played a moderating role in the mediation effects of positive affect and negative affect. Therefore, appropriate measures should be taken to strengthen Chinese college students' perceived risk and provide them with corresponding guidance. The importance of physical exercise should also be emphasized to help college students with low perceived risk reduce negative affect, increase positive affect, and promote their preventive behavior.

Karst ecosystems are widely distributed around the world, accounting for 15–20% of the global land area. However, knowledge on microbial ecology of these systems does not match with their global importance. To close this knowledge gap, we sampled three niches including weathered rock, sediment, and drip water inside the Heshang Cave and three types of soils overlying the cave (forest soil, farmland soil, and pristine karst soil). All these samples were subjected to high-throughput sequencing of V4-V5 region of 16S rRNA gene and analyzed with multivariate statistical analysis. Overall, archaeal communities were dominated by Thaumarchaeota, whereas Actinobacteria dominated bacterial communities. Thermoplasmata, Nitrosopumilaceae, Aenigmarchaeales, Crossiella, Acidothermus, and Solirubrobacter were the important predictor groups inside the Heshang Cave, which were correlated to NH4+ availability. In contrast, Candidatus Nitrososphaera, Candidatus Nitrocosmicus, Thaumarchaeota Group 1.1c, and Pseudonocardiaceae were the predictors outside the cave, whose distribution was correlated with pH, Ca2+, and NO2−. Tighter network structures were found in archaeal communities than those of bacteria, whereas the topological properties of bacterial networks were more similar to those of total prokaryotic networks. Both chemolithoautotrophic archaea (Candidatus Methanoperedens and Nitrosopumilaceae) and bacteria (subgroup 7 of Acidobacteria and Rokubacteriales) were the dominant keystone taxa within the co-occurrence networks, potentially playing fundamental roles in obtaining energy under oligotrophic conditions and thus maintaining the stability of the cave ecosystem. To be noted, all the keystone taxa of karst ecosystems were related to nitrogen cycling, which needs further investigation, particularly the role of archaea. The predicted ecological functions in karst soils mainly related to carbohydrate metabolism, biotin metabolism, and synthesis of fatty acid. Our results offer new insights into archaeal ecology, their potential functions, and archaeal interactions with bacteria, which enhance our understanding about the microbial dark matter in the subsurface karst ecosystems.

In this paper, we present port-Hamiltonian formulations of the incompressible Euler equations with a free surface governed by surface tension and gravity forces, modelling e.g. capillary and gravity waves and the evolution of droplets in air. Three sets of variables are considered, namely $(v,\Sigma)$, $(\eta,\phi_{\partial},\Sigma)$ and $(\omega,\phi_{\partial},\Sigma)$, with $v$ the velocity, $\eta$ the solenoidal velocity, $\phi_{\partial}$ a potential, $\omega$ the vorticity, and $\Sigma$ the free surface, resulting in the incompressible Euler equations in primitive variables and the vorticity equation. First, the Hamiltonian formulation for the incompressible Euler equations in a domain with a free surface combined with a fixed boundary surface with a homogeneous boundary condition will be derived in the proper Sobolev spaces of differential forms. Next, these results will be extended to port-Hamiltonian formulations allowing inhomogeneous boundary conditions and a non-zero energy flow through the boundaries. Our main results are the construction and proof of Dirac structures in suitable Sobolev spaces of differential forms for each variable set, which provides the core of any port-Hamiltonian formulation. Finally, it is proven that the state dependent Dirac structures are related to Poisson brackets that are linear, skew-symmetric and satisfy the Jacobi identity.

It is still unclear about the effects of context and working memory capacity on different types of irony reading, and three experiments were conducted to explore the effects of context and working memory capacity on ironic criticism and ironic praise.

Sub-3 nm aluminum (Al) nanocrystal is an emerging class of nanomaterial with properties distinct to noble metal nanoclusters. The complete solution synthesis of aluminum nanoclusters was recently reported, and their photoluminescence (PL) observed for the first time. At the moment, there exists no method to tune the size of ultrasmall aluminum nanocrystals in solution thus no knowledge on the boundary state between aluminum nanoclusters to plasmonic nanoparticles. In this work, it is demonstrated a study of size-controlled solution synthesis of ultrasmall aluminum nanocrystals with size controlled between ∼ 2.2 to ∼ 3.8 nm. Increasing the size results in three sets of spectral responses: (1) absorption due to nascent plasmons generated at ∼ 340 nm for larger particles, confirmed by Mie theory calculations; (2) significant decreased quantum yield of PL from ∼ 7.8% to ∼ 2.4%, indicating reduced quantum confinement effects and increased metallicity; (3) drop of fluorescence lifetime was observed, especially when the diameter of aluminum nanoparticles was changed from ∼ 3.0 to ∼ 3.8 nm. This study provides experimental evidence and insights to the transitional state between aluminum nanoclusters to plasmonic nanoparticles, which seems to occur at size larger than gold nanoclusters.

HighlightsAutomatic navigation technology in autonomous tractors is one of the key technologies in precision agriculture.A path-tracking control algorithm based on lateral deviation and yaw rate feedback is proposed.The modified steering angle was obtained by comparing the ideal yaw rate with the actual yaw rate.The results demonstrate the efficiency and superior accuracy of the proposed algorithm for tractor path-tracking control.Abstract. The performance of path-tracking control systems for autonomous tractors affects the quality and efficiency of farmland operations. The objective of this study was to develop a path-tracking control algorithm based on lateral deviation and yaw rate feedback. The autonomous tractor path lateral dynamics model was developed based on preview theory and a two-degree-of-freedom tractor model. According to the established dynamic model, a path-tracking control algorithm using yaw angular velocity correction was designed, and the ideal steering angle was obtained by lateral deviation and sliding mode control. The modified steering angle was obtained by a proportional-integral-derivative feedback controller after comparing the ideal yaw rate with the actual yaw rate, which was then combined with the ideal steering angle to obtain the desired steering angle. The simulation and experimental results demonstrate the efficiency and superior accuracy of the proposed tractor path-tracking control algorithm, enabling its application in automatic navigation control systems for autonomous tractors. Keywords: Autonomous tractor, Path-tracking control, Sliding mode control, Yaw rate feedback.

When sample data are governed by an unknown sequence of independent but possibly non-identical distributions, the data-generating process (DGP) in general cannot be perfectly identified from the data. For making decisions facing such uncertainty, this paper presents a novel approach by studying how the data can best be used to robustly improve decisions. That is, no matter which DGP governs the uncertainty, one can make a better decision than without using the data. I show that common inference methods, e.g., maximum likelihood and Bayesian updating cannot achieve this goal. To address, I develop new updating rules that lead to robustly better decisions either asymptotically almost surely or in finite sample with a pre-specified probability. Especially, they are easy to implement as are given by simple extensions of the standard statistical procedures in the case where the possible DGPs are all independent and identically distributed. Finally, I show that the new updating rules also lead to more intuitive conclusions in existing economic models such as asset pricing under ambiguity., Accepted version at EC'22, 48 pages

Additional file 1: Table S1. Laboratory Examination Data on Admission. Table S2. Data of GnRH agonist stimulating test. Table S3. Endocrinological Examination Data after HFMD.

Cheng(2021) proposes and characterizes Relative Maximum Likelihood (RML) updating rule when the ambiguous beliefs are represented by a set of priors. Relatedly, this note proposes and characterizes Extended RML updating rule when the ambiguous beliefs are represented by a convex capacity. Two classical updating rules for convex capacities, Dempster-Shafer (Shafer, 1976) and Fagin-Halpern rules (Fagin and Halpern, 1990) are included as special cases of Extended RML., 10 pages. arXiv admin note: substantial text overlap with arXiv:1911.02678

This note shows that the value of ambiguous persuasion characterized in Beauchene, Li and Li(2019) can be given by a concavification program as in Bayesian persuasion (Kamenica and Gentzkow, 2011). In addition, it implies that an ambiguous persuasion game can be equivalently formalized as a Bayesian persuasion game by distorting the utility functions. This result is obtained under a novel construction of ambiguous persuasion., 11 pages, fixing typos

In a persuasion game, if both the sender and receiver are ambiguity averse, can the sender benefit from sending ambiguous messages? This paper shows that the sender cannot benefit from introducing ambiguity if the receiver is dynamically consistent. This result is obtained when both players' preferences are represented by the Maxmin Expected Utility (MEU) criterion. However, if the sender is strictly less ambiguity averse than the receiver (in the sense of alpha-MEU), then she may benefit even when facing a dynamically consistent receiver. This gain comes from extracting an \textit{ambiguity premium} by exploiting the differences in the ambiguity attitudes., 17 pages

Although there are many types of trip planning systems, and many of them have already been put into commercial use, most of the known trip planning systems have some defects, such as the inability to integrate multiple modes of transportation when planning the itinerary. Without considering the special needs of different groups of people, etc., if users want to achieve combined travel, they still need to manually search and match, thus reducing the user experience. The system is based on the A-star algorithm [1], considering the transportation modes commonly used by people, such as subways, high-speed rails, and airplanes, to construct an intelligent planning system for travel between cities. The system can realize the city A subway station as the starting point, the city B subway station as the destination, integrate various urban and inter-city transportation modes, intelligently plan the complete travel route, and provide the “most time-saving” and “most Save money and “most comfortable” three planning options.

Programa de Doctorado en Investigación en Medios de Comunicación por la Universidad Carlos III de Madrid Presidente: Rafael Gómez Alonso.- Secretario: Alejandro Barranquero Carretero.- Vocal: Carlota Coronado Ruiz

Xiaoyu Cheng,1 Ming Li,1 Xi Rao,1 Wenfeng Zhang,1 Xiaopeng Li,1 Liang Wang,1 Guanjun Huang2 1Department of Infectious Disease, The First Affiliated Hospital of Nanchang University, Nanchang, JiangXi, China; 2Department of Endocrinology, Shangrao People’s Hospital, Shangrao, JiangXi, China Purpose: N6-methyladenosine (m6A), the most abundant mRNA modification in mammals, is involved in various biological processes. KIAA1429 is an important methyltransferase participating in m6A modification. However, the role of KIAA1429 in hepatocellular carcinoma (HCC) is still not well understood. Here, we aimed to investigate the function of KIAA1429 and its corresponding regulation mechanisms in HCC.Patients and methods: HCC-related genes were analyzed by clinical and expression data of HCC patients in The Cancer Genome Atlas (TCGA) database. Expression of KIAA1429 was verified by quantitative reverse-transcription PCR, and interference efficiency was obtained using small interfering RNA (siRNA). Cell proliferation, migration, and invasion were assessed by cell counting kit-8and transwell assays, and the m6A modification was detected by methylated RNA immunoprecipitation-PCR (MeRIP-PCR).Results: We found a difference in the expression of KIAA1429 between HCC and normal hepatic tissues by analyzing data from the TCGA database. Comparing HCC cell lines (HepG2, Huh-7, HepG2.2.15) with normal hepatic cells (HL-7702), we observed an identically significant difference in KIAA1429 expression. KIAA1429 significantly enhanced proliferation, migration, and invasion of HepG2 cells. Moreover, Kyoto Encyclopedia of Genes and Genomes functional enrichment analysis and correlation analysis revealed a significant negative correlation between KIAA1429 and ID2. In the subsequent MeRIP-PCR assay, downregulation of KIAA1429 inhibited m6A modification of ID2 mRNA.Conclusion: KIAA1429 facilitated migration and invasion of HCC by inhibiting ID2 via upregulating m6A modification of ID2 mRNA. Keywords: N6-methyladenosine, methyltransferases, tumor metastasis, invasion &nbsp

Herein, a series of novel iron nitride (Fe2N)/cubic-ordered mesoporous carbon (OMC) composites (Fe2N@OMC) were synthesized via a facile nanocasting route and ammonia calcination. Physical characterization results indicate that small non-aggregated Fe2N nanoparticles were evenly distributed on the external surface and in the pores of the carbon material with a linear array of mesopores in a regular interval arrangement. An electrochemical test was carried out using Fe2N@OMC as a negative electrode of a supercapacitor in 6 mol L−1 KOH aqueous electrolytes. The results indicated that the obtained Fe2N@OMC-2 exhibited a superior specific capacitance of 547 F g−1 at 1 mV s−1 and 520 F g−1 at 0.5 A g−1, an excellent rate capability (398 F g−1 at 20 A g−1 with capacitance retention of 76%), and an outstanding cycling stability. After 1000 cycles, the specific capacitance retention of Fe2N@OMC-2 remained 85%, which was much higher than 28% of the bare Fe2N.

A method for the determination of triazine herbicides in water samples was established by magnetic effervescence tablet-assisted switchable hydrophilicity solvent-based liquid phase microextraction procedure (META-SHS-LPME) coupled with high-performance liquid chromatography with diode array detection. The magnetic effervescence tablet, composed of citric acid, sodium hexanoate, sodium bicarbonate, and Fe3O4 nanoparticles, combined extractant generation, dispersion, and magnetic recovery into one step. Citric acid could react with sodium hexanoate and sodium bicarbonate to generate hexanoic acid and carbon dioxide in situ, respectively. Carbon dioxide bubbles assisted the eco-friendly extractant hexanoic acid to fully contact with target compounds. Fe3O4 nanoparticles containing extractant and triazine herbicides were isolated from the sample solution using an external magnet. Good linearity was achieved in the range of 50–5000 ng mL−1 with a correlation coefficient greater than 0.997. The limit of detection was within 0.10–0.13 ng mL−1. The extraction recovery of triazine herbicides were 81.4–96.7% in well, pond, and river waters. Overall, the proposed method was a simple, efficient, and eco-friendly analytical approach for determining triazine herbicide residues in water samples.

Quantum dots (QDs) are semiconductor nanocrystals with unique photophysical properties. Quantum dots have drawn broad research interests in the past three decades, because of their applications in optoelectronic devices, solar cells and fluorescent imaging agents in biomedicine. However, a major issue for the further development of this new class of materials is that many quantum dots are composed of heavy metal elements that are considered unsafe for biological purposes. Therefore, concerns over nanoparticle related toxicity have inspired the design of quantum dots made from materials with biological benign nature, such as crystalline silicon (Si). The first challenge of working with nanocrystalline silicon quantum dots (SiQDs) is the limited methods available to prepare high quality, surface functionalized nanoparticles. Among the various methods available, colloidal synthesis is of broad interests, for the simple procedures used and solution-based approaches as needed in many applications. In this thesis, chapter three and chapter four describe two new approaches of coping with this challenge, using a one-step method based on thiol-ene chemistry, and a two-step process based on copper catalyzed azide-alkyne cycloaddition (CuAAC) reaction respectively. The second challenge of applying solution synthesized SiQDs for bio-imaging is their blue photoluminescence that can be affected by biological background signals, as well as the low excitation wavelength that may induce damage to cellular structures. Most responses to this challenge have been focused on material preparation, but limited success has been achieved when solution syntheses are involved. In this thesis, chapter five presents a completely different strategy of resolving this issue by focusing on advanced microscopy. Specifically, fluorescence lifetime imaging microscopy (FLIM) is used to observe SiQDs in intracellular contexts, utilizing their long fluorescence lifetime in the context of one-photon FLIM, two-photon FLIM and energy transfer studies (FLIM-FRET). Lastly, since surface modified colloidal SiQDs is still in its infancy of development, there are still limited studies showing their applications as biosensors. In chapter six, efforts toward the preparation of the first SiQDs protease sensor is described. This is based on Förster Resonance Energy Transfer (FRET) process involving SiQDs-dye construct, where SiQDs were used as the donor, and conjugated to an organic dye acceptor via an enzyme responsive peptide linker.

Four groups of mice were dissected at various time intervals from 0.5 to 144 hours after their intravenous injection of uranium. The uranium distribution and deposition in the tissues of kidney, lung, marrow, liver, heart, muscle and blood have been studied using the fission track technique (FTT). Our experimental results show that trace uranium is more likely to be deposited in kidneys and lungs than in marrow and liver. The presence of uranium in the blood is so transient that blood-uranium level cannot be used to estimate the degree of the storage of uranium in the body. However, the mice injected with high dose uranium die soon because the uranium poisons the heart severely.

Silicon is the second most abundant element in Earth’s crust, and it is considered one of the most important materials for the world. Crystalline silicon has continued to serve as the foundational building block for the microelectronic industry, and new forms of silicon materials have promised an even brighter future with emerging applications from optoelectronic devices, energy and environment technologies and new therapeutics [1–3]. Many of these promises are often associated with reduction of the physical size of the material to the micro/nano scale which yields novel physical properties. For this reason,understanding and learning how to control these features is of high importance, and unsurprisingly, low dimension silicon structures have drawn broad research interests from physicists, chemists, materials engineers and medical scientists. Refereed/Peer-reviewed