Permanence of a Discrete Periodic Volterra Model with Mutual Interference and Beddington-DeAngelis Functional Response

This paper discuss a discrete periodic Volterra model with mutual interference and Beddington-DeAngelis functional response. By using the comparison theorem of difference equation, sufficient conditions are obtained for the permanence of the system. After that,we give an example to show the feasibility of our main result

Using Polygraph to Detect Passengers Carrying Illegal Items

The present study examined the effectiveness of a Modified-Comparison Questions Technique, used in conjunction with the polygraph, to differentiate between common travelers, drug traffickers, and terrorists at transportation hubs. Two experiments were conducted using a mock crime paradigm. In Experiment 1, we randomly assigned 78 participants to either a drug condition, where they packed and lied about illicit drugs in their luggage, or a control condition, where they did not pack or lie about any illegal items. In Experiment 2, we randomly assigned 164 participants to one of the two conditions in Experiment 1 or an additional bomb condition, where they packed and lied about a bomb in their luggage. For both experiments, we assessed participants’ RR interval, heart rate, peak-to-peak amplitude of Galvanic Skin Response (GSR) and all three combined, using Discriminant Analyses to determine the classification accuracy of participants in each condition. In both experiments, we found decelerated heart rates and increased peak-to-peak amplitude of GSR in guilty participants when lying in response to questions regarding their crime. We also found accurate classifications of participants, in both Experiment 1 (drug vs. control: 84.2% vs. 82.5%) and Experiment 2 (drug vs. control: 82:1% vs. 95.1%; bomb vs. control: 93.2% vs. 95.1%; drug vs. bomb: 92.3% vs. 90.9%), above chance level. These findings indicate that Modified-CQT, combined with a polygraph test, is a viable method for investigating suspects of drug trafficking and terrorism at transportation hubs such as train stations and airports

DeepSeek-V2: A Strong, Economical, and Efficient Mixture-of-Experts Language Model

We present DeepSeek-V2, a strong Mixture-of-Experts (MoE) language model characterized by economical training and efficient inference. It comprises 236B total parameters, of which 21B are activated for each token, and supports a context length of 128K tokens. DeepSeek-V2 adopts innovative architectures including Multi-head Latent Attention (MLA) and DeepSeekMoE. MLA guarantees efficient inference through significantly compressing the Key-Value (KV) cache into a latent vector, while DeepSeekMoE enables training strong models at an economical cost through sparse computation. Compared with DeepSeek 67B, DeepSeek-V2 achieves significantly stronger performance, and meanwhile saves 42.5% of training costs, reduces the KV cache by 93.3%, and boosts the maximum generation throughput to 5.76 times. We pretrain DeepSeek-V2 on a high-quality and multi-source corpus consisting of 8.1T tokens, and further perform Supervised Fine-Tuning (SFT) and Reinforcement Learning (RL) to fully unlock its potential. Evaluation results show that, even with only 21B activated parameters, DeepSeek-V2 and its chat versions still achieve top-tier performance among open-source models

Identification and molecular cloning of novel antimicrobial peptides from skin secretions of Odorrana versabilis and Rana palustris

Objective: Amphibian skin secretions are an abundant source of bioactive peptides, some of which could be developed as candidate drugs. Among these natural peptides, cytolytic peptides have attracted the most attention given that they might replace conventional antibiotics and help deal with the problem of microbial resistance. This study discovered two bioactive peptides, Brevinin-1-PLr and Nigrocin-2-OV, from two species frogs, the Chinese bamboo leaf odorous frog (Odorrana versabilis) and the North American pickerel frog (Rana palustris), respectively. Their antimicrobial, anticancer and hemolytic activities were also investigated. Methods: cDNA sequences encoding peptides were cloned from cDNA libraries constructed from the lyophilized secretions of the Chinese bamboo leaf odorous frog and the North American pickerel frog. By reversed-phase HPLC and MS/MS fragmentation sequencing, the encoded novel peptides, named Nigrocin-2-OV and Brevinin-1-PLr, were identified in skin secretions and their structures were confirmed. Replicates of both peptides were produced through solid phase peptide synthesis. Their antimicrobial and anticancer activity was studied against three types of microorganisms (Staphylococcus aureus, Candida albicans, and Escherichia coli) and five cancer cell lines (NCI-H157, PC-3, MDA-MB-435s, MCF-7, and U251MG). Their hemolytic activity was investigated using whole horse blood. Results: In this research, cDNA sequences encoding two novel 24-mer peptides were cloned from cDNA libraries constructed from the lyophilized skin secretions of the Chinese bamboo leaf odorous frog and the North American pickerel frog. Both of the peptides had the strongest inhibitory effect against C. albicans, and IC50 values against five cancer cell lines were all under 6 μM. Conclusions: Nigrocin-2-OV and Brevinin-1-PLr had the strong ability to inhibit the proliferation of studied microorganisms and tumor cell lines, with slight hemolytic activity. Compared with Brevinin-1-PLr, Nigrocin-2-OV exhibited higher antimicrobial and anticancer activity but slightly higher hemolytic activity

Dynamic behaviors of a nonlinear amensalism model

Abstract A nonlinear amensalism model of the form dN1dt=r1N1(1−(N1P1)α1−u(N2P1)α2),dN2dt=r2N2(1−(N2P2)α3), $$\begin{aligned} &\frac{dN_{1}}{dt}= r_{1}N_{1} \biggl(1- \biggl( \frac{N_{1}}{P_{1}} \biggr)^{\alpha _{1}}-u \biggl(\frac{N_{2}}{P_{1}} \biggr)^{\alpha_{2}} \biggr), \\ &\frac{dN_{2}}{dt}= r_{2}N_{2} \biggl(1- \biggl( \frac{N_{2}}{P_{2}} \biggr)^{\alpha_{3}} \biggr), \end{aligned}$$ where ri,Pi,u,i=1,2,α1,α2,α3 $r_{i}, P_{i}, u, i=1, 2, \alpha_{1}, \alpha_{2}, \alpha_{3}$ are all positive constants, is proposed and studied in this paper. The dynamic behaviors of the system are determined by the sign of the term 1−u(P2P1)α2 $1-u (\frac{P_{2}}{P_{1}} )^{\alpha_{2}}$. If 1−u(P2P1)α2>0 $1-u (\frac {P_{2}}{P_{1}} )^{\alpha_{2}}>0$, then the unique positive equilibrium D(N1∗,N2∗) $D(N_{1}^{*},N_{2}^{*})$ is globally attractive, if 1−u(P2P1)α2<0 $1-u (\frac{P_{2}}{P_{1}} )^{\alpha_{2}}<0$, then the boundary equilibrium C(0,P2) $C(0, P_{2})$ is globally attractive. Our results supplement and complement the main results of Xiong, Wang, and Zhang (Advances in Applied Mathematics 5(2):255–261, 2016)

Permanence and Global Attractivity of the Discrete Predator-Prey System with Hassell-Varley-Holling III Type Functional Response

By constructing a suitable Lyapunov function and using the comparison theorem of difference equation, sufficient conditions which ensure the permanence and global attractivity of the discrete predator-prey system with Hassell-Varley-Holling III type functional response are obtained. An example together with its numerical simulation shows that the main results are verifiable