Staphylococcus aureus and biofilms:transmission, threats, and promising strategies in animal husbandry

Staphylococcus aureus(S. aureus) is a common pathogenic bacterium in animal husbandry that can cause diseases such as mastitis, skin infections, arthritis, and other ailments. The formation of biofilms threatens and exacerbates S. aureus infection by allowing the bacteria to adhere to pathological areas and livestock product surfaces, thus triggering animal health crises and safety issues with livestock products. To solve this problem, in this review, we provide a brief overview of the harm caused by S. aureus and its biofilms on livestock and animal byproducts(meat and dairy products). We also describe the ways in which S. aureus spreads in animals and the threats it poses to the livestock industry. The processes and molecular mechanisms involved in biofilm formation are then explained. Finally, we discuss strategies for the removal and eradication of S. aureus and biofilms in animal husbandry, including the use of antimicrobial peptides, plant extracts, nanoparticles, phages, and antibodies. These strategies to reduce the spread of S. aureus in animal husbandry help maintain livestock health and improve productivity to ensure the ecologically sustainable development of animal husbandry and the safety of livestock products.

Distributed Dynamic Load in Structural Dynamics by the Impulse-Based Force Estimation Algorithm

This paper proposes a novel approach for identifying distributed dynamic loads in the time domain.Using polynomial andmodal analysis,the load is transformed intomodal space for coefficient identification.This allows the distributed dynamic load with a two-dimensional form in terms of time and space to be simultaneously identified in the form of modal force,thereby achieving dimensionality reduction.The Impulse-based Force Estimation Algorithm is proposed to identify dynamic loads in the time domain.Firstly,the algorithm establishes a recursion scheme based on convolution integral,enabling it to identify loads with a long history and rapidly changing forms over time.Secondly,the algorithm introduces moving mean and polynomial fitting to detrend,enhancing its applicability in load estimation.The aforementioned methodology successfully accomplishes the reconstruction of distributed,instead of centralized,dynamic loads on the continuum in the time domain by utilizing acceleration response.To validate the effectiveness of the method,computational and experimental verification were conducted.

Multi-Source Underwater DOA Estimation Using PSO-BP Neural Network Based on High-Order Cumulant Optimization

Due to the complex and changeable environment under water,the performance of traditional DOA estimation algorithms based on mathematical model,such as MUSIC,ESPRIT,etc.,degrades greatly or even some mistakes can be made because of the mismatch between algorithm model and actual environment model.In addition,the neural network has the ability of generalization and mapping,it can consider the noise,transmission channel inconsistency and other factors of the objective environment.Therefore,this paper utilizes Back Propagation(BP)neural network as the basic framework of underwater DOA estimation.Furthermore,in order to improve the performance of DOA estimation of BP neural network,the following three improvements are proposed.(1)Aiming at the problem that the weight and threshold of traditional BP neural network converge slowly and easily fall into the local optimal value in the iterative process,PSO-BP-NN based on optimized particle swarm optimization(PSO)algorithm is proposed.(2)The Higher-order cumulant of the received signal is utilized to establish the training model.(3)A BP neural network training method for arbitrary number of sources is proposed.Finally,the effectiveness of the proposed algorithm is proved by comparing with the state-of-the-art algorithms and MUSIC algorithm.

Optimal design of anchor cables for slope reinforcement based on stress and displacement fields

How to determine reasonable position and length of anchor cable is a frequently encountered but not well addressed problem in slope reinforcement projects. In this paper, the variable-modulus elastoplastic strength reduction method （SRM） is used to obtain the stress field, displacement field, and factor of safety of slope. Slope reinforcement using anchor cables is modeled by surface loading, i.e. different distributions of surface loading represent various reinforcement schemes. Optimal reinforcement scheme of anchor cables can be determined based on slope stress and displacement fields. By comparing the factor of safety and stress field before and after slope reinforcement, it is found that better rein-forcement results can be achieved if strong reinforcement is applied upon the regions with high stress and large displacement. This method can well optimize the arrangement of anchor cables. In addition, several cases are employed to verify the proposed method.

Explore economic restructuring Institutional Analysis based on the urban-rural dual economic structure

China＇ s urban and rural economic and social structures are persisted, perfectly shaped, very typical. Since the new century, the Chinese government began to adjust serious distorted urban-rural relations. New rural construction, total abolition of agricultural tax, the construction of modern agriculture and other major strategic decisions have been introduced; free compulsory education in rural areas, the new rural cooperative medical care, rural public infrastructure, cultural services and other specific measures have been rolled out building. But these still can not slow down our growing urban-rural gap, China＇ s economic and social development is still running under the urban and rural pattern, and the trend has increased.

Tax system＇s effect on income regulating distribution

Problems caused by the income distribution gap arises widespread attention in current theorists, sector and folk. Requiring adjustment of income distribution gap is growing from various aspects and this article attempts to investigate theoretical level of influence in government regulating income distribution gap, mainly involving the government and the blur, efficiency loss in market boundaries, the deficit effects and other aspects of government failure. We strive to prevent the possible deviations of goverrmaent in the implementation of the regulation, expect to deepen understanding and promote the practice for some benefit.

THE DESIGN AND CLINICAL APPLICATION OF TOTALANKLE PROSTHESIS WITH PARTIAL TIBIA

The authors applied the first total ankle with partial tibial replacement forthe tumor of the tibia and fibula in 1987. We have followed this case for 10 years.Up to now, the outcome of this operation is very good, with no tumor recurrenceand good function. According to the experiences, the authors raised the technicalindexes of design, the indications, incision, surgical procedures, and warnings.

Phage-displayed heptapeptide sequence conjugation significantly improves the specific targeting ability of antimicrobial peptides against Staphylococcus aureus

Broad-spectrum antibacterial drugs often lack specificity,leading to indiscriminate bactericidal activity,which can disrupt the normal microbial balance of the host flora and cause unnecessary cytotoxicity during systemic administration.In this study,we constructed a specifically targeted antimicrobial peptide against Staphylococcus aureus by introducing a phage-displayed peptide onto a broad-spectrum antimicrobial peptide and explored its structure–function relationship through one-factor modification.SFK2 obtained by screening based on the selectivity index and the targeting index showed specific killing ability against S.aureus.Moreover,SFK2 showed excellent biocompatibility in mice and piglet,and demonstrated significant therapeutic efficacy against S.aureus infection.In conclusion,our screening of phage-derived heptapeptides effectively enhances the specific bactericidal ability of the antimicrobial peptides against S.aureus,providing a theoretical basis for developing targeted antimicrobial peptides.

新游戏,新规则:大数据在组织管理研究中的应用

随着互联网、云计算等信息技术的发展,海量的非结构化和半结构化数据得到整合,人类社会因此步入大数据时代。大数据为社会发展带来一场巨大的技术变革,被广泛应用于各个领域。尽管大数据的应用为组织管理研究提供了新的研究视角、研究方法和研究路径,但现有研究对于为什么应用以及如何应用大数据仍缺乏明确的指导。本文首先回顾了大数据的发展历程,并探讨了大数据对组织管理研究的重要意义。其次,提供了以归纳法为哲学方法论基础的研究范式,并阐明大数据背景下归纳研究法的优势,为传统基于演绎逻辑及假设检验的定量研究提供了一种结合大数据的研究形式。再次,进一步介绍了大数据研究的主要步骤及分析工具。最后,对大数据在组织管理领域的应用前景进行了展望。

An insight into aggregation kinetics of polystyrene nanoplastics interaction with metal cations

Once inevitably released into the aquatic environment,polystyrene nanoplastics(PS-NPs)will present complicated environmental behaviors,of which the aggregation is a key process determining their environmental fate and impact.In this study,the aggregation kinetics of different sizes(30 nm and 100 nm)of PS-NPs with metal cations(Na^(+),K^(+),Ca^(2+),Mg^(2+)and Pb^(2+))at different solution pH(3,6 and 8)were investigated.The results showed that the aggregation of PS-NPs increased with cation concentration.Taking Pb^(2+)as an example,the adsorption behavior of cations onto PS-NPs was determined by transmission electron microscopy(TEM)and energy dispersive X-ray(EDX)spectroscopy,which demonstrated Pb^(2+)could be adhered onto the surface of PS-NPs with the effect of charge neutralization.The critical coagulation concentrations(CCC)of smaller PS-NPs were higher than that of larger PS-NPs for monovalent cations,whereas a different pattern is observed for divalent cations.It was suggested that there were other factors that DLVO theory does not consider affect the stability of NPs with different particle sizes.In addition,it should be noted that PS-NPs had the capacity of adsorbing large amounts of heavy metal cations and carried them transport to a long distance,and the corresponding ecological risks need to further elucidate.

Full-scale evaluation of reversed A^(2)/O process for removal of multiple pollutants in sewage

This study evaluated the removal of multiple pollutants,i.e.,polybrominated diphenyl ethers(PBDEs),novel halogenated flame retardants(HFRs),sulfonamide antibiotics(SAs),and heavy metals(HMs),by a fullscale reversed A^(2)/O process in a sewage treatment plant(STP)in Guangzhou,China.The reversed A^(2)/O process demonstrated high removal efficiencies(REs)for total PBDEs(60.5%±4.3%),novel HFRs(98.4%±2.8%)and HMs(70.1%±1.2%),and a relatively low RE for SAs(25.0%±2.3%).BDE 209,the dominant PBDE congener,showed a high residual concentration(13.41±5.18 ng/L)in the suspended particulate matter(SPM)of treated effluents.So me novel HFRs,dechlorane plus(DP)and decabromodiphe nyl ethane(DBDPE),were detected in the SPM of the raw sewage(7.50±4.14 ng/L and 11.52±11.65 ng/L,respectively).The removal ofSAs was mainly through biodegradation in the activated sludge bioreactors(ASBs).Ofthe HMs,Mn and Ni exhibited the lowest REs(47.5%±2.2%and 35.0%±2.6%,respectively),while Cr and Cu showed the highest removal(REs>80%).In terms of treatment units in the reversed A^(2)/O process,ASBs showed the highest RE(27.8%)for the multiple pollutants.The information can aid in our understanding of removal properties of STPs on various pollutants and evaluating the ecological/health risks of STPs as point pollutant sources.

4×4 MIMO fiber-wireless transmission based on an integrated four-channel directly modulated optical transceiver

In this paper, an integrated compact four-channel directly modulated analog optical transceiver is proposed and fabricated. The 3 d B bandwidth of this optical transceiver exceeds 20 GHz, and the measured spurious-free dynamic range is up to 91.2 d B · Hz^2∕3. The optical coupling efficiency(CE) is improved by using a precise submicron alignment technique for lens coupling in a transmitter optical subassembly, and the highest CE is achieved when the oblique angle of the arrayed waveguide grating using a silica-based planar lightwave circuit(AWG-PLC) in receiver optical sub assembly is set to 42°. Based on the proposed optical transceiver, we have experimentally demonstrated a 6.624 Gbit/s 4 × 4 multi-input multioutput(MIMO) 16-quadrature amplitude modulation orthogonal frequency division multiplexing(16 QAM-OFDM) radio signal over 15.5 km standard single mode fiber, together with 1.2 m wireless transmission in both an uplink and a downlink. To cope with the channel interference and noise of the fiber-wireless transmission system, a low-complexity MIMO demodulation algorithm based on lattice reduction zero-forcing(LR-ZF) is designed. In our experiment, 1.6 d B power penalty is achieved by using the proposed LR-ZF algorithm, compared to the commonly used zero-forcing algorithm.Moreover, this LR-ZF algorithm has much less complexity than the optimal maximum-likelihood sequence estimation(MLSE) at a given transmission performance. These results not only demonstrate the feasibility of the integrated optical transceiver for MIMO fiber-wireless application but also validate that the proposed LR-ZF algorithm is effective to eliminate the interference for hybrid fiber-wireless transmission.