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A graph $G$ is called $C_{2k+1}$-free if it does not contain any cycle of length $2k+1$. In 1981, Haggkvist, Faudree and Schelp showed that every $n$-vertex triangle-free graph with more than $\frac{(n-1)^2}{4}+1$ edges is bipartite. In this paper, we extend their result and show that for $1\leq t\leq 2k-2$ and $n\geq 318t^2k$, every $n$-vertex $C_{2k+1}$-free graph with more than $\frac{(n-t-1)^2}{4}+\binom{t+2}{2}$ edges can be made bipartite by either deleting at most $t-1$ vertices or deleting at most $\binom{\lfloor\frac{t+2}{2}\rfloor}{2}+\binom{\lceil\frac{t+2}{2}\rceil}{2}-1$ edges. The construction shows that this is best possible.

Natural language is expected to be a key medium for various human-machine interactions in the era of large language models. When it comes to the biochemistry field, a series of tasks around molecules (e.g., property prediction, molecule mining, etc.) are of great significance while having a high technical threshold. Bridging the molecule expressions in natural language and chemical language can not only hugely improve the interpretability and reduce the operation difficulty of these tasks, but also fuse the chemical knowledge scattered in complementary materials for a deeper comprehension of molecules. Based on these benefits, we propose the conversational molecular design, a novel task adopting natural language for describing and editing target molecules. To better accomplish this task, we design ChatMol, a knowledgeable and versatile generative pre-trained model, enhanced by injecting experimental property information, molecular spatial knowledge, and the associations between natural and chemical languages into it. Several typical solutions including large language models (e.g., ChatGPT) are evaluated, proving the challenge of conversational molecular design and the effectiveness of our knowledge enhancement method. Case observations and analysis are conducted to provide directions for further exploration of natural-language interaction in molecular discovery.

The theory of magnetic-source electromagnetic anomalous diffusion is developed in this article. As the geological medium is spatially rough, the late-time tail phenomenon can be explained as a multiscale electromagnetic anomalous diffusion, which is a union of fractional subdiffusion and regular diffusion. The roughness parameter $\beta $ and weighting parameter $W$ are introduced into the generalized electrical conductivity to indicate the roughness level and ratio. The characteristics and superiority of the improved generalized electrical conductivity are analyzed in the time domain. A 3-D modeling method is proposed based on the fractional finite-difference time-domain method. The introduced Caputo fractional derivative in the time domain is calculated by the Alikhanov superconvergent approximation method, so that the stability of the solution is improved. Several half-space models are designed to verify the 3-D modeling efficiency. It turns out that the improved generalized electrical conductivity can model the electromagnetic late-time tail efficiently, which is characterized by responses that coincide with the classical attenuation law at earlier times and the departure at later times. Moreover, this approach is also applied to anomalous models with 3-D bodies; the results indicate that the proposed method can recognize 3-D anomalous bodies efficiently. The improved method can model the complex electromagnetic propagation in the rough geologic medium more accurately, providing a theoretical basis for multiscale and refined detection.

Fowl adenovirus serotype-4 (FAdV-4) is highly lethal to poultry, making it one of the leading causes of economic losses in the poultry industry. However, a small proportion of poultry can survive after FAdV-4 infection. It is unclear whether there are genetic factors that protect chickens from FAdV-4 infection. Therefore, the livers from chickens uninfected with FAdV-4 (Normal), dead after FAdV-4 infection (Dead) or surviving after FAdV-4 infection (Survivor) were collected for RNA-seq, and 2,649 differentially expressed genes (DEGs) were identified. Among these, many immune-related cytokines and chemokines were significantly upregulated in the Dead group compared with the Survivor group, which might indicate that death is related to an excessive inflammatory immune response (cytokine storm). Subsequently, the KEGG results for DEGs specifically expressed in each comparison group indicated that cell cycle and apoptosis-related DEGs were upregulated and metabolism-related DEGs were downregulated in the Dead group, which also validated the reliability of the samples. Furthermore, GO and KEGG results showed DEGs expressed in all three groups were mainly associated with cell cycle. Among them, BRCA1, CDK1, ODC1, and MCM3 were screened as factors that might influence FAdV-4 infection. The qPCR results demonstrated that these 4 factors were not only upregulated in the Dead group but also significantly upregulated in the LMH cells after 24 h infection by FAdV-4. Moreover, interfering with BRCA1, CDK1, ODC1, and MCM3 significantly attenuated viral replication of FAdV-4. And interfering of BRCA1, CDK1, and MCM3 had more substantial hindering effects. These results provided novel insights into the molecular changes following FAdV-4 infection but also shed light on potential factors driving the survival of FAdV-4 infection in chickens.

Let $F$ be an $(r+1)$-color critical graph with $r\geq 2$, that is, $\chi(F)=r+1$ and there is an edge $e$ in $F$ such that $\chi(F-e)=r$. Gerbner recently conjectured that every $n$-vertex maximal $F$-free graph with at least $(1-\frac{1}{r})\frac{n^2}{2}- o(n^{\frac{r+1}{r}})$ edges contains an induced complete $r$-partite graph on $n-o(n)$ vertices. Let $F_{s,k}$ be a graph obtained from $s$ copies of $C_{2k+1}$ by sharing a common edge. In this paper, we show that for all $k\geq 2$ if $G$ is an $n$-vertex maximal $F_{s,k}$-free graph with at least $n^{2}/4 - o(n^{\frac{s+2}{s+1}})$ edges, then $G$ contains an induced complete bipartite graph on $n-o(n)$ vertices. We also show that it is best possible. This disproves Gerbner's conjecture for $r=2$., Comment: 20pages,1 figures

The OFDM technology is widely used in wireless communication systems, but it is highly sensitive to narrowband interference (NBI). The existing NBI suppression algorithms are mainly for single NBI or multiple NBIs with an assumption that the frequency distance of the multiple NBIs is large enough. However, in reality, there are more and more multiple interacting NBIs with small frequency distance, such as NB-IoT. Unfortunately, due to the interaction of multiple NBIs, the performance of existing NBI suppression algorithms is degraded. Aiming at this problem, we propose a multiple interacting NBIs suppression algorithm jointed time-frequency domain for OFDM systems. First, in order to achieve a high-precision and low-complexity frequency estimate for a single NBI, an interference frequency estimation method based on chirp-z transform (CZT-IFE) is studied. Then, for multiple interacting NBIs, based on the analysis of NBI frequency distance and spectral aliasing, a highly robust interference frequency estimation method combining IIR notch filter and CZT-IFE (NF-CZT-IFE) is given. It eliminates the interaction of multiple NBIs and obtains the accurate frequency estimates of the NBIs. Finally, based on NF-CZT-IFE, the multiple interacting NBIs are suppressed by using IIR notch filters. Simulation results demonstrate that the proposed multiple interacting NBIs suppression algorithm has better interference suppression performance on the NBIs with different frequency distances and different interference numbers. The proposed algorithm improves the robustness of OFDM systems in complex NBI environments.

Crowdsourcing, in which human intelligence and productivity is dynamically mobilized to tackle tasks too complex for automation alone to handle, has grown to be an important research topic and inspired new businesses (e.g., Uber, Airbnb). Over the years, crowdsourcing has morphed from providing a platform where workers and tasks can be matched up manually into one which leverages data-driven algorithmic management approaches powered by artificial intelligence (AI) to achieve increasingly sophisticated optimization objectives. In this paper, we provide a survey presenting a unique systematic overview on how AI can empower crowdsourcing - which we refer to as AI-Empowered Crowdsourcing(AIEC). We propose a taxonomy which divides algorithmic crowdsourcing into three major areas: 1) task delegation, 2) motivating workers, and 3) quality control, focusing on the major objectives which need to be accomplished. We discuss the limitations and insights, and curate the challenges of doing research in each of these areas to highlight promising future research directions.

Shipeng Wang,1,2,* Hui Gao,3,* Zewen Ru,1 Yanan Zou,1 Yilan Li,1 Wei Cao,4 Wei Meng,1 Jihe Li,5 Yuan Yao,1 Yanxiu Zhang,1 Xueyan Lang,1 Yao Zhang1,2 1Department of Cardiology, The Second Affiliated Hospital of Harbin Medical University, Harbin 150086, People’s Republic of China; 2Key Laboratory of Myocardial Ischemia, Ministry of Education, Harbin Medical University, Harbin 150086, People’s Republic of China; 3Department of Cardiology, People’ Hospital of Xinzheng, Xinzheng, Henan Province 451150, People’s Republic of China; 4Department of Cardiology, Heilongjiang Provincial Hospital Affiliated to Harbin Institute of Technology, Harbin 150036, People’s Republic of China; 5Department of Cardiology, The First Affiliated Hospital of Harbin Medical University, Harbin 150001, People’s Republic of China*These authors contributed equally to this workCorrespondence: Shipeng WangDepartment of Cardiology, The Second Affiliated Hospital of Harbin Medical University, Xuefu Road 246#, Nangang District, Harbin 150086, People’s Republic of ChinaTel +86 13654504286Fax +86 86296225Email guoyunqaz@126.comBackground: Sleep disorders (SDs) are usually associated with an increase in frequency of ventricular tachycardia (VT). However, the relationship between SDs and the prevalence of VT within the first week of acute myocardial infarction (AMI) remains unclear. This study aimed to evaluate their associations and potential mechanisms.Methods: This structured questionnaire-based cross-sectional study enrolled 303 patients with AMI from a hospital in northern China. Pittsburgh Sleep Quality Index (PSQI) was used to determine sleep quality of subjects. Heart rate variability (HRV) of patients was investigated by ambulatory electrocardiography recorders. Enzyme-linked immunosorbent assay was used to measure the plasma levels of catecholamine in a subgroup including 80 patients with AMI.Results: After adjusting to basic cardiovascular characteristics, results of multivariate logistic regression demonstrated that the global PSQI score and its main components were positively associated with VT prevalence in inpatients with AMI. There were significantly different HRV parameters interpreted as autonomic nerve activity in two groups of AMI patients with different sleep quality. In addition, we found the influence of sleep quality on plasma concentrations of adrenaline and norepinephrine in AMI patients.Conclusion: Sleep status was significantly associated with the initiation of VT within the first week of AMI, probably due to the effect of SDs on sympathetic nerve activity. Amelioration of sleep quality and sympathetic hyperactivity may be prospective strategy to curb arrhythmias after AMI.Keywords: ventricular tachycardia, acute myocardial infarction, sleep disorders, heart rate variability, catecholamine

Objective To summarize the incidence, clinical manifestations, diagnosis and treatment of basal cell ne⁃ vus syndrome and to provide reference for clinical diagnosis and treatment. Methods Retrospective analysis of 4 cas⁃ es of basal cell nevus syndrome admitted to the General Hospital of PLA during January 2017 to January 2018 and re⁃ cent cases reported in the literature. Results In this study, 1 males and 3 females were included. The patients includ⁃ ed a mother and her child. All 4 cases were surgically resected. Pathological reports included all keratocysts of the jaws. There has been no recurrence since follow⁃up. Through literature summarization and analysis, the clinical manifesta⁃ tions of this syndrome were found to be diverse. Typical clinical manifestations include multiple keratocysts of the jaws, multiple blepharospasms or cancers, deformities of the spine or ribs, increased brachial distance, eye diseases or special face intracranial calcification. Conclusion Basal cell nevus syndrome is an autosomal dominant genetic disorder. The clinical manifestations are diverse and the diagnosis is often overlooked. The incidence of cysts in the jaws is one of the important clinical manifestations of this syndrome. Early diagnosis and proper treatment improve patient survival and quality of life.

BACKGROUND: Patients with non-ST-segment elevation myocardial infarction (NSTEMI) have a generally poor prognosis and antithrombotic management patterns (AMPs) used post-acute coronary syndrome (ACS) remain unclear. Duration of dual antiplatelet therapy (DAPT) and patient characteristics was evaluated in NSTEMI patients enrolled in EPICOR Asia. HYPOTHESIS: Patients stopping DAPT early may benefit from more intensive monitoring. METHODS: EPICOR Asia was a prospective, real-world, primary data collection, cohort study in adults with an ACS, conducted in eight countries/regions in Asia, with 2 year follow-up. Eligible patients were hospitalized within 48 hours of symptom onset and survived to discharge. We describe AMPs and baseline characteristics in NSTEMI patients surviving ≥12 months with DAPT duration ≤12 and > 12 months post-discharge. Clinical outcomes (composite of death, myocardial infarction, and stroke; and bleeding) were also explored. RESULTS: At discharge, 90.8% of patients were on DAPT (including clopidogrel, 99%). At 1- and 2-year follow-up, this was 79.2% and 60.0%. Patients who stopped DAPT ≤12 months post-discharge tended to be older, female, less obese, have prior cardiovascular disease, and have renal dysfunction. While causality cannot be inferred, the incidence of the composite endpoint over the subsequent 12 months was 10.6% and 3.1% with shorter vs longer use of DAPT, and mortality risk over the same period was 8.4% and 1.6%. CONCLUSIONS: Over 90% of NSTEMI patients were discharged on DAPT, with 60% on DAPT at 2 years. Patients stopping DAPT early were more likely to have higher baseline risk and may therefore benefit from more intensive monitoring during long-term follow-up.

For any positive integer $k$, we show that every maximal $C_{2k+1}$-free graph with at least $n^2/4-o(n^{3/2})$ edges contains an induced complete bipartite subgraph on $(1-o(1))n$ vertices. We also show that this is best possible., Comment: 12 pages

Magnetic titanium dioxide core-shell nanoparticles(Fe3O4@TiO2 NPs) were synthesized as particles with appropriate size for intravenous injection. They subsequently were functionalized with p-aminothiophenol(PATP) to facilitate the covalent attachment of target drugs through azo coupling reaction, which can be universally observed in a variety of drugs containing phenols, anilines, and imidazoles. The proposed drug nanocarrier was designed to possess the ability to release drugs upon UV irradiation because of the photocatalytic property of the TiO2 shells. All the results indicate the potential application of the Fe3O4@TiO2 NPs in targeted drug delivery with greater chemical sta-bility and universality.

Energy consumption of the data center is one of the main constraints for the development of data centers in developed regions. Shanghai has clearly defined the conditions and requirements for the construction of the data center. Through the scheme demonstration and economic analysis of gas distributed energy stations for the data center in Shanghai, the energy economy is the main factor restricting the gas distribution energy supply for the data center. Under the current background, the gas distributed energy station for the data center in Shanghai is more suitable for the construction of third-party investment operation and maintenance entities, which can significantly reduce the power usage effectiveness of the data center, although the annual energy cost of the data center increase significantly. At the same time, gas distributed energy stations need to pay attention to expand winter heat users and improve the equivalent utilization hours of energy stations to achieve greater economic benefits.

The equivalent sample theory and its application in analysis of networked control system (NCS) are presented. After analyzing NCS's scheduling in master-slave mode, the characteristics of time delay and sample are summarized. Looking on master station visiting the slave station as a special sample process, the theory of equivalent sample is presented. And based on it, the stability of a kind of NCS is analyzed. The criterion to determine the upper bound of transmission delay is introduced, which guarantees the stability. Finally, an example with simulation shows the availability and usability of this analysis method.