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目的 探讨颞浅动脉-大脑中动脉端侧吻合术中不同临时阻断技术的效果及可靠性。 方法 回顾性分析2015年1月—2023年4月南方医科大学南方医院神经外科收治的接受直接搭桥术治疗的烟雾病患者资料，根据临时阻断策略的不同将患者分为3组：①有垫片、多阻断夹阻断组（multi-clips+rubber pad group，M+R组）；②无垫片、多阻断夹阻断组（multi-clips group，M组）；③无垫片、单阻断夹阻断组（single-clip group，S组）。比较组间临时阻断时间、受体动脉切开后有无渗血、术中穿支血管损伤以及术后新发脑梗死情况。 结果 共355例患者、360个大脑半球纳入分析，按大脑半球统计患者360例，其中男性188例，女性172例，平均年龄为（43.8±0.7）岁。其中M+R组45例，M组191例，S组124例。3组平均阻断时间：M+R组为（37.9±9.8）min，M组为（20.9±9.0）min，S组为（11.0±3.5）min，组间差异有统计学意义（P＜0.001）。阻断后受体动脉管腔内渗血以及术中穿支血管损伤发生率：M+R组为8.89%（阻断后受体动脉渗血4例），M组为14.66%（阻断后受体动脉渗血19例，术中穿支血管损伤8例，临时阻断部位有血栓形成1例），S组为5.65%（阻断后受体动脉渗血7例），组间差异无统计学意义（P>0.05）。术后新发脑梗死发生率差异无统计学意义（P>0.05）。 结论 单阻断夹阻断策略安全、有效，能显著缩短临时阻断时间，可以优先考虑作为颞浅动脉-大脑中动脉端侧吻合过程中的临时阻断策略。 Abstract: Objective To investigate the effects and reliability of different temporary occlusion techniques in end-to-side anastomosis of the superficial temporal artery-middle cerebral artery. Methods A retrospective analysis was conducted on the data of patients with Moyamoya disease who underwent direct bypass surgery in the Department of Neurosurgery, Nanfang Hospital, Southern Medical University, from January 2015 to April 2023. The patients were divided into three groups according to the different temporary occlusion strategies: ①multi-clips+rubber pad group (M+R group); ②multi-clips group (M group); and ③single-clip group (S group). Temporary occlusion time, presence of errhysis after recipient artery incision, intraoperative perforator vessel injury, and postoperative novel cerebral infarction were compared among the three groups. Results A total of 355 patients and 360 cerebral hemispheres were included in the analysis, and 360 patients were counted according to the number of cerebral hemispheres, including 188 males and 172 females, with an average age of (43.8±0.7) years. There were 45 cases in the M+R group, 191 cases in the M group, and 124 cases in the S group. The average occlusion time were (37.9±9.8) minutes in the M+R group, (20.9±9.0) minutes in the M group, and (11.0±3.5) minutes in the S group, with significant differences between the groups (P0.05). There was no significant difference in the incidence of novel cerebral infarctions postoperatively (P>0.05). Conclusions The single-clip occlusion strategy is safe and effective, which significantly shortens the temporary occlusion time, and should be prioritized as the temporary occlusion technique in end-to-side anastomosis of the superficial temporal artery-middle cerebral artery.

Beam profile measurement via wire scanner is a semi-invasive method, which has advantage of less beam influence compared with a profile target, and is widely used in particle accelerator all over the world. Wire scanner is adopted to be applied to Shanghai High Repetition Rate X-ray Free Electron Laser aNd Extreme Light Facility (SHINE). For this purpose, a prototype of wire scanner composed of a wire target, a set of mechanical mechanism, a beam loss monitor and a set of electronics was designed and developed. A tungsten wire with an outer diameter of 20 μm was used as the wire target, and the safety of this tungsten wire was proved by thermal simulation. The beam loss monitor in the wire scanner prototype consists of a quartz fiber that generates Cherenkov light, and a photomultiplier tube. The data acquisition module was developed based on the ADQ14AC-4C data acquisition platform from Teledyne SP Devices, which is equipped with ADC chip with nominal bit of 14 bit, effective bit of about 9 bit, and analog 3 dB bandwidth of 1.2 GHz. The principle and specific design of the prototype were introduced in this paper. The optimization scheme of installing a cavity beam position monitor (CBPM) upstream of the wire target to accurately compensate the beam center position and the beam charge was also mentioned. In order to accurately evaluate performance of the prototype, we measured the beam profile simultaneously by arranging wire scanner system and a YAG target adjacent to each other in Shanghai Soft X-ray Free Electron Laser (SXFEL). The comparison of the experimental results show that the wire scanner can be used for the online semi-invasive beam profile measurement of the 0.84 GeV electron beam with a bunch charge of 500 pC. The resolustion of the prototype wire scanner is better than 30 μm, and especially less than 10 μm in the direction of low beam jitter. When the beam position changes greatly, the measurement accuracy of the prototype wire scanner is sharply improved by the CBPM system. Furthermore, the relative charge quantity calculated by the CBPM reference cavity signal is used to compensate the beam loss signal, and the measurement result of the prototype wire scanner is slightly improved. The results of the profile target agree with those of the prototype wire scanner well which verify the function of the device applied to SXFEL. The prototype of wire scanner system has laid a good technical foundation for SHINE construction, and at the same time, wire scanner system with CBPM can be used as a supplement for beam profile measurement in SXFEL.

The SHINE based on the superconducting linear accelerator is the first quasi-continuous wave hard X-ray free electron laser user facility under construction in China. It has the characteristics of high repetition rate of 1 MHz max, low bunch charge about 100 pC and large scale about 31 km. In order to reduce the decay of the output power of FEL radiation, it requires a beam position monitor (BPM) system with resolution of two hundred nanometers to realize the close interaction and energy exchange between the electron beam and the photon beam in the undulator. The BPM system that has been developed for SXFEL cannot fully meet the requirements. Therefore, based on the quantitative relationship between the relative amplitude extraction uncertainty of the cavity BPM signal and the main parameters of each subsystem, as well as the reasonable allocation of key technical indicators, a prototype of cavity BPM system was designed and developed, which consists of a Cband cavity BPM pickup, a radio frequency (RF) front-end with the character of signal-channel down converted RF signal to low intermediate frequency (IF) signal and low noise figure, and a dedicated digital BPM signal processor. As a bridge between the cavity pickup and the digital BPM signal processor, the structure and performance of the RF frontend also determine the performance of the CBPM system directly. In this paper, based on the SHINE’s demand for cavity BPM system, the key technical indicators of the RF frontend were analyzed, the scheme of amplifier switching type RF frontend was proposed, and the advantages of the RF frontend schemes with amplifier switching type and the adjustable attenuation type were compared and analyzed by the method of parametric simulation. And an offline full phaselocked sampling test bench which can simulate beam conditions is also successfully built for the first time. In addition, the beam test bench was built in SXFEL facility and the performance evaluation of the RF frontend was completed. Based on the evaluation method of power divided, the experiment results show that the position resolution can reach 71 nm under the condition of bunch charge of 100 pC and the system dynamic range of ±100 μm, which is consistent with the theoretical value and better than the design requirement of the SHINE.

BackgroundThe Shanghai high repetition rate XFEL and extreme light facility (SHINE) accelerates electrons up to 8 GeV using cryogenic-superconducting high-frequency cavity. Wire scanner system is applied to the beam profile measurement of SHINE due to its advantages such as fewer secondary particles generation compared with that of complete beam block, hence reduce the risk of superconducting cavity.PurposeThis study aims to design data acquisition system for wire scanner system and realize synchronous acquisition of beam loss signal and relative position between the wire and beam.MethodsThe data acquisition system for wire scanner was designed to include radio frequency (RF) daughter board with analog signal digitizer, digital motherboard, firmware, data processing software. A Zynq-UltraScale+ based system on chip (SoC) was employed as system central component, and a field programmable gate array (FPGA) was used for system control and data transmission whilst the advanced RISC machine (ARM) integrating Linux was implemented for data acquisition and communication. Finally, experimental test of this data acquisition system was performed on the testbed to verify its feasibility and functionalities.ResultsThe data acquisition system can correctly read back position of grating ruler, and achieve synchronous acquisition of sample beam loss signal and signal of cavity beam position monitor.ConclusionsThe data acquisition system meets the requirements of SHINE wire scanner system. It will be applied to the prototype of SHINE wire scanner system.

Ophiocordyceps sinensis , an entomopathogenic fungus, infects larvae from the Lepidoptera: Hepialidae family, forming the valuable Chinese cordyceps. Mycoviruses are widespread across major lineages of filamentous fungi, oomycetes, and yeasts and have the potential to influence fungal biology and ecology. This study aimed to detect mycovirus within O. sinensis by isolating double-stranded RNA from six stains for transcriptomic sequencing and analyzing publicly available transcriptome data from 13 O. sinensis representative samples. Our analysis revealed 13 mycoviruses, with nine reported for the first time in O. sinensis. These mycoviruses are distributed across five families— Partitiviridae , Mitoviridae , Narnaviridae , Botourmiaviridae , Deltaflexiviridae —and two unclassified lineages, Ormycovirus and Vivivirus. This study also revealed frequent coinfections within individual O. sinensis strains and dynamic shifts in viral composition during fungal development. These findings enhance our knowledge of mycovirus diversity within O. sinensis and provide new insights into their taxonomy. [ABSTRACT FROM AUTHOR]

Fluorescence intensity ratio (FIR) technology is compulsorily needed in non-contact rare-earth luminescent temperature sensors. Here, we present Er/Yb:Y3Al5O12 phosphors synthesized via a high-temperature solid-state reaction method. The crystal structure, microstructure, up-conversion luminescence, and energy transfer between the two ions have been comprehensively analyzed. Under 980-nm excitation, the samples exhibited four distinct transition bands at 475 nm, 525 nm, 546 nm, and 664 nm. The quantum efficiency reached 12.14%. Utilizing the thermally coupled level of I525/I546 as a basis for analysis yields a maximum relative sensitivity of 1.05% K−1. We observed that the spectral color coordinates varied linearly with temperature within a specific range, suggesting its potential application as a means of temperature measurement. Furthermore, employing the non-thermally coupled levels of I546/I475 for temperature measurement results in an impressive maximum absolute sensitivity of 8.05% K−1, nearly 24 times higher than that achieved through thermally coupled levels alone. The temperature resolution of the synthetic material is basically less than 0.3 K with high thermal stability. Therefore, Er/Yb:Y3Al5O12 phosphors hold promise as viable candidates for components in temperature-sensor applications. [ABSTRACT FROM AUTHOR]

Blockchain technology holds the potential to revolutionise the logistics industry by sharing tamper-proof information in a decentralised manner, building trust among parties. However, adoption in the Australian logistics industry lags behind other sectors. This study uses fuzzy DEMATEL to investigate barriers to blockchain adoption, identifying thirteen key barriers within the technology-organisation-environment (TOE) framework. Cost of investment and integration difficulties among partners are the most prominent barriers, particularly within organisational contexts. The findings offer a theoretical foundation and practical insights for overcoming barriers and successfully implementing blockchain in logistics. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the genetic diversity of IncG plasmids, we have proposed a typing scheme based on replicon repA and performed comparative genomic analysis of five IncG plasmids from China. Methods: p30860-KPC, p116965-KPC, pA1705-KPC, pA1706-KPC and pNY5520-KPC total in five IncG plasmids from clinical isolates of Pseudomonas and Enterobacteriaceae, respectively, were fully sequenced and were compared with the previously collected reference plasmid p10265-KPC. Results: Based on phylogeny, IncG-type plasmids are divided into IncG-I to IncG-VIII, the five plasmids belong to IncG-VIII. A detailed sequence comparison was then presented that the IncG plasmid involved accessory region I (Tn 5563a/b/c/d/e), accessory region II (ISpa19), and accessory region III (blaKPC-2-region). Expect for the pNY5520-KPC, the rest of the plasmids had the same backbone structure as the reference one. Within the plasmids, insertion sequences Tn 5563d and Tn 5563e were identified, a novel unknown insertion region was found in Tn 5563b/c/d/e. In addition, Tn 6376b and Tn 6376c were newly designated in the study. Conclusion: The data presented here including a typing scheme and detailed genetic comparison which provide an insight into the diversification and evolution history of IncG plasmids. [ABSTRACT FROM AUTHOR]

In order to study the transmission error of the cylindrical gear with arcuate tooth trace，a torsional vibration model of the cylindrical gear with arcuate tooth trace transmission system is proposed，and a dynamics model is established based on 3D model.The influence of tooth width，tooth line radius，load and rotation speed on the transmission error is analyzed.The results show that，the transmission error fluctuates periodically around 0 when the structure parameters and working conditions are different； the transmission error amplitude decreases first and then increases with the increase of the tooth width； the transmission error amplitude changes in shape of “W” with the increase of the tooth line radius，that is，it first decreases and then increases with the increase of the tooth line radius，and then first decreases and then increases with the increase of the tooth line radius； the transmission error amplitude increases with the increase of load and rotating speed.The results provide the theoretical basis for the noise reduction and lubrication，fault diagnosis and gear tooth geometric modification of the cylindrical gear with arcuate tooth trace.

Mild‐heat photothermal antibacterial therapy avoids heat‐induced damage to normal tissues but causes bacterial tolerance. The use of photothermal therapy in synergy with chemodynamic therapy is expected to address this issue. Herein, two pseudo‐conjugated polymers PM123 with photothermal units and PFc with ferrocene (Fc) units are designed to co‐assemble with DSPE‐mPEG2000 into nanoparticle NPM123/Fc. NPM123/Fc under 1064 nm laser irradiation (NPM123/Fc+NIR‐II) generates mild heat and additionally more toxic ∙OH from endogenous H2O2, displaying a strong synergistic photothermal and chemodynamic effect. NPM123/Fc+NIR‐II gives >90% inhibition rates against MDR ESKAPE pathogens in vitro. Metabolomics analysis unveils that NPM123/Fc+NIR‐II induces bacterial metabolic dysregulation including inhibited nucleic acid synthesis, disordered energy metabolism, enhanced oxidative stress, and elevated DNA damage. Further, NPM123/Fc+NIR‐II possesses >90% bacteriostatic rates at infected wounds in mice, resulting in almost full recovery of infected wounds. Immunodetection and transcriptomics assays disclose that the therapeutic effect is mainly dependent on the inhibition of inflammatory reactions and the promotion of wound healing. What is more, thioketal bonds in NPM123/Fc are susceptible to ROS, making it degradable with highly favorable biosafety in vitro and in vivo. NPM123/Fc+NIR‐II with a unique synergistic antibacterial strategy would be much less prone to select bacterial resistance and represent a promising antibiotics‐alternative anti‐infective measure. [ABSTRACT FROM AUTHOR]

Purpose: Pseudomonas aeruginosa is a common causative bacteria in nosocomial infections. This study aims to describe the structure and evolutionary characteristics of mobile genetic elements (MGEs) carrying antibiotic resistance genes (ARGs) from P. aeruginosa and to conduct bioinformatics and comparative genomic analysis to provide a deeper understanding of the genetic characteristics and diversity of MGEs in P. aeruginosa. Methods: Fifteen clinical isolates of P. aeruginosa from China were collected and sequenced in this study, and 15 novel MGEs were identified. Together with four MGEs from GenBank, a total of 19 MGEs were used to perform detailed modular structure dissection and sequence comparison. Then, the biological experiments were carried out to verify the biological characteristics of these isolates and MEGs. Results: The novel MGEs identified in this study displayed diversification in modular structures, which showed complex mosaic natures. The seven types of 19 MGEs included in this study were divided into three groups: i) novel MGEs (firstly identified in this study): four IncpSE5381-aadB plasmids and three Tn 7495-related integrative and mobilizable elements (IMEs); ii) newly defined MGEs (firstly designated in this study, but with previously determined sequences): four Tn 7665-related IMEs; iii) novel transposons with reference prototypes identified in this study: two Tn 6417-related integrative and conjugative elements (ICEs), two IS-based transposition units, two Tn 501-related unit transposons, two Tn 1403-related unit transposons. At least 36 ARGs involved in resistance to 11 different classes of antimicrobials and heavy metals were identified. Additionally, three novel blaOXA variants were identified. Antimicrobial susceptibility testing showed that these variants were resistant to some β-lactamase antibiotics and blaOXA-1204 was additionally resistant to cephalosporins. Conclusion: The continuous evolution of ARG-carrying MGEs during transmission, leading to the emergence of novel MGEs or ARGs, which facilitates the spread of antibiotic resistance in P. aeruginosa and enhances the diversity of transmission modes of bacterial resistance. [ABSTRACT FROM AUTHOR]

The Genre Fiction Workshop is one of the latest teaching approach and exploratory initiative within Fudan University's Creative Writing program, evolving from the Fiction Workshop established by Wang Anyi. The Genre Fiction Workshop adopts "practice + discussion" as its teaching model, and the utilization of a predefined writing topic as its teaching characteristic. On this basis, the workshop introduces narrative techniques specific to genre fiction and an anonymous review mechanism, prompting students to accumulate narrative skills, break writing conventions, and discern the quality of their exercises, in order to foster their professional literary proficiency ultimately. Meanwhile, the workshop represents a valuable reference for the innovative advancement of creative writing programs. The workshop boasts a clear classroom process, a rich evaluation system, and notable teaching effects, providing a useful reference for the innovative development of the Creative Writing major. [ABSTRACT FROM AUTHOR]

Rotaviruses are rising as zoonotic viruses worldwide, causing the lethal dehydrating diarrhea in children, piglets, and other livestock of economic importance. A simple, swift, cost-effective, highly specific, and sensitive antigen-capture enzyme–linked immunosorbent assay (AC-ELISA) was developed for detection of porcine rotavirus-A (PoRVA) by employing rabbit (capture antibody) and murine polyclonal antibodies (detector antibody) produced against VP6 of PoRVA (RVA/Pig-tc/CHN/TM-a/2009/G9P23). Reactivity of the both polyclonal antibodies was confirmed by using an indirect ELISA, western-blot analysis and indirect fluorescence assay against rVP6 protein and PoRVA. The detection limit of AC-ELISA was found 50 ng/ml of PoRVA protein. The relative sensitivity and specificity of this in-house AC-ELISA were evaluated for detection of PoRVA from 295 porcine diarrhea samples, and results were compared with that of RT-PCR and TaqMan RT-qPCR. The relative sensitivity and specificity of AC-ELISA compared with those of TaqMan RT-qPCR were found as 94.4 and 99.2%, respectively, with the strong agreement (κ −0.58) between these two techniques. Furthermore, AC-ELISA could not detect any cross-reactivity with porcine epidemic diarrhea virus, transmissible gastro-enteritis virus, pseudo rabies virus and porcine circovirus-2. This in-house AC-ELISA efficiently detected PoRVA from clinical samples, which suggests that this technique can be used for large-scale surveillance and timely detection of rotavirus infection in the porcine farms. In this study, we used a Chinese porcine rotavirus-A (PoRVA) strain containing the I5, a dominant VP6-genotype in pigs, for production of VP6 (most conserved) protein based polyclonal antibodies (pAb) in rabbits (as capture Ab) and mouse (as detector Ab) for development of simple, cost effective, highly specific and sensitive AC-ELISA for detection of PoRVA. Furthermore, there is no any previous published report on application of rabbit and mouse pAb against VP6 for developing an AC-ELISA against PoRVA. [ABSTRACT FROM AUTHOR]

Nickel base superalloys are widely used to manufacture turbine blades, and overheating poses a serious threat to the safe service of turbine blades. In this study, a second-generation nickel base single crystal superalloy was taken as the research object, and we carried out the overheating treatment at 1100 °C and 1300 °C, and then tested the creep properties at 1000 °C/300 MPa and 1100 °C/130 MPa. Through systematic analysis of creep properties, γ/γ' phases, and creep voids, the effects of overheating on the microstructures and creep properties of the experimental superalloy were revealed. The results demonstrate that the effect of overheating at 1100 °C on the microstructure of the experimental superalloy can be ignored, and the effect on the creep property is limited. The degree of γ' dissolution is gradually increased and the creep property is reduced with overheating time extending at the overheating temperature of 1300 °C. [ABSTRACT FROM AUTHOR]

In this paper, the residual stresses with a nanoscale depth resolution at TSV-Cu/TiW/SiO2/Si interfaces under different thermal loadings are characterized using the ion-beam layer removal (ILR) method. Moreover, the correlations of residual stress, microstructure, and the failure modes of the interfaces are discussed. The residual stresses at the interfaces of TSV-Cu/TiW, TiW/SiO2, and SiO2/Si are in the form of small compressive stress at room temperature, then turn into high-tensile stress after thermal cycling or annealing. In addition, the maximum residual stress inside the TSV-Cu is 478.54 MPa at room temperature, then decreases to 216.75 MPa and 90.45 MPa, respectively, after thermal cycling and annealing. The microstructural analysis indicates that thermal cycling causes an increase in the dislocation density and a decrease in the grain diameter of TSV-Cu. Thus, residual stress accumulates constantly in the TSV-Cu/TiW interface, resulting in the cracking of the interface. Furthermore, annealing leads to the cracking of more interfaces, relieving the residual stress as well as increasing the grain diameter of TSV-Cu. Besides this, the applicability of the ILR method is verified by finite element modeling (FEM). The influence of the geometric errors of the micro-cantilever beam and the damage to the materials introduced by the focused ion beam (FIB) in the experimental results are discussed. [ABSTRACT FROM AUTHOR]

Clinical therapy of multidrug resistant (MDR) bacteria‐induced deep‐tissue infections such as pneumonia is highly challenging. Ultrasound (US)‐induced sonodynamic therapy (SDT) is a promising strategy for treatment of deep‐tissue diseases given the strong tissue penetration of US. Here, ZIF‐8‐derived carbon@TiO2 nanoparticles (ZTNs) are developed as inhalable sonosensitizers for bacterial pneumonia. ZTNs upon US irradiation exhibit an excellent efficacy to produce reactive oxygen species (ROS) and thereby to kill Gram‐negative MDR bacteria in vitro. Taking advantage of aerosolized intratracheal inoculation, ZTNs can be precisely delivered to lung infection sites, and display an effective SDT‐based elimination of Gram‐negative MDR bacteria in the lung infection models of immunocompetent or immunodeficient mice. Particularly, ZTNs upon US irradiation give a 100% survival rate in the severely immunodeficient NOD/SCID mice with a lethal bacterial pneumonia. In addition, ZTNs have no obvious toxicity at both cellular and animal levels. Metal–organic‐framework‐derived nanoparticles as safe and efficient inhalable sonosensitizer have a great potential to be used for the clinical antibiotics‐alternative treatment of MDR bacterial pneumonia. This study presents a new paradigm for SDT‐based treatment of deep‐tissue bacterial infections, and will expand the nanomedicine application of inorganic sonosensitizers. [ABSTRACT FROM AUTHOR]

Photothermal therapy based on conjugated polymers represents a promising antibacterial strategy but still possesses notable limitations. Herein, degradable pseudo conjugated polymers (PCPs) containing photothermal molecular backbones and reactive oxygen species (ROS)‐sensitive thioketal bonds are designed. Triphenylphosphine (PPh3) is introduced into PCPs to generate phosphonium‐based PCPs (pPCPs), which further assembled with hyaluronic acid into pPCP nanoparticles (pPCP‐NPs). pPCP‐NPs with quaternary phosphonium cations selectively anchor on and destroy bacterial cell membranes through electrostatic action. Under 1064 nm laser irradiation, pPCP‐NPs (pPCP‐NPs/+L) produce near‐infrared‐II (NIR‐II) photothermal antibacterial effect, thereby killing bacteria in a sustained manner. pPCP‐NPs are readily degraded upon ROS abundant at infection sites, therefore exhibiting enough biosafety. pPCP‐NPs/+L display an almost 100% bacterial inhibition rate in vitro and resultin a nearly complete recovery of bacteria‐induced mouse wounds. A further metabolomics analysis denotes that pPCP‐NPs/+L work in a concerted way to induce bacterial DNA damage, inhibit bacterial carbon/nitrogen utilization and amino acid/nucleotide synthesis. Taken together, degradable pPCP‐NPs with both NIR‐II photothermal effect and cationic phosphonium structural bacteriostasis provide a new avenue for antibiotics‐alternative anti‐infection therapy. [ABSTRACT FROM AUTHOR]

Background: The carbapenem-resistance genes blaVIM are widely disseminated in Pseudomonas, and frequently harbored within class 1 integrons that reside within various mobile genetic elements (MGEs). However, there are few reports on detailed genetic dissection of blaVIM-carrying MGEs in Pseudomonas. Methods: This study presented the complete sequences of five blaVIM-2/-4-carrying MGEs, including two plasmids, two chromosomal integrative and mobilizable elements (IMEs), and one chromosomal integrative and conjugative element (ICE) from five different Pseudomonas isolates. Results: The two plasmids were assigned to a novel incompatibility (Inc) group IncpSTY, which included only seven available plasmids with determined complete sequences and could be further divided into three subgroups IncpSTY-1/2/3. A detailed sequence comparison was then applied to a collection of 15 MGEs belonging to four different groups: three representative IncpSTY plasmids, two Tn6916-related IMEs, two Tn6918-related IMEs, and eight Tn6417-related ICEs and ten of these 15 MGEs were first time identified. At least 22 genes involving resistance to seven different categories of antibiotics and heavy metals were identified within these 15 MGEs, and most of these resistance genes were located within the accessory modules integrated as exogenous DNA regions into these MGEs. Especially, eleven of these 15 MGEs carried the blaVIM genes, which were located within 11 different concise class 1 integrons. Conclusion: These blaVIM-carrying integrons were further integrated into the above plasmids, IMEs/ICEs with intercellular mobility. These MGEs could transfer between Pseudomonas isolates, which resulted in the accumulation and spread of blaVIM among Pseudomonas and thus was helpful for the bacteria to survival from the stress of antibiotics. Data presented here provided a deeper insight into the genetic diversification and evolution of VIM-encoding MGEs in Pseudomonas. [ABSTRACT FROM AUTHOR]

In this study, a detailed genetic dissection of the huge and complex bla NDM-carrying genetic elements and their related mobile genetic elements was performed in Enterobacteriaceae. An extensive comparison was applied to 12 chromosomal genetic elements, including six sequenced in this study and the other six from GenBank. These 12 genetic elements were divided into five groups: a novel IME Tn 6588 ; two related IMEs Tn 6523 (SGI1) and Tn 6589 ; four related ICEs Tn 6512 (R391), Tn 6575 (ICE Pvu ChnBC22), Tn 6576 , and Tn 6577 ; Tn 7 and its derivatives Tn 6726 and 40.7-kb Tn 7 -related element; and two related IMEs Tn 6591 (GI sul2) and Tn 6590. At least 51 resistance genes, involved in resistance to 18 different categories of antibiotics and heavy metals, were found in these 12 genetic elements. Notably, Tn 6576 carried another ICE Tn 6582. In particular, the six bla NDM-carrying genetic elements Tn 6588 , Tn 6589 , Tn 6575 , Tn 6576 , Tn 6726 , and 40.7-kb Tn 7 -related element contained large accessory multidrug resistance (MDR) regions, each of which had a very complex mosaic structure that comprised intact or residual mobile genetic elements including insertion sequences, unit or composite transposons, integrons, and putative resistance units. Core bla NDM genetic environments manifested as four different Tn 125 derivatives and, notably, two or more copies of relevant Tn 125 derivatives were found in each of Tn 6576 , Tn 6588 , Tn 6589 , and 40.7-kb Tn 7 -related element. The huge and complex bla NDM-carrying genetic elements were assembled from complex transposition and homolog recombination. Firstly identified were eight novel mobile elements, including three ICEs Tn 6576 , Tn 6577 , and Tn 6582 , two IMEs, Tn 6588 and Tn 6589 , two composite transposons Tn 6580a and Tn 6580b , and one integron In1718. [ABSTRACT FROM AUTHOR]

The numerical technique—finite difference method (FDM) is one well‐known computational method requiring a delicate meshing algorithm used to optimize the simulation accuracy of complicated electromagnetic (EM) structures. The widely used Yee's staggered lattices discretize the EM field components and require the structured cubic meshing data. The structured mesh has intrinsic limitations on simulating irregular formations and objects. By applying a reliable numerical material‐mixing method to calculate the effective properties of mesh cells, the 2.5D FDM solver, with this numerical method implemented, can observe the inclined layers and the thin fracture in the formation without extra grids on interfaces. The tool responses from the practical complex formation with and without fracture showing up a distinguished difference in tool responses can be observed, verifying the validity of the proposed analysis strategies. [ABSTRACT FROM AUTHOR]

Pseudomonas aeruginosa is noted for its intrinsic antibiotic resistance and capacity of acquiring additional resistance genes. In this study, the genomes of nine clinical P. aeruginosa isolates were fully sequenced. An extensive genetic comparison was applied to 18 P. aeruginosa accessory genetic elements (AGEs; 13 of them were sequenced in this study and located within P. aeruginosa chromosomes) that were divided into four groups: five related integrative and conjugative elements (ICEs), four related integrative and mobilizable elements (IMEs), five related unit transposons, and two related IMEs and their two derivatives. At least 45 resistance genes, involved in resistance to 10 different categories of antibiotics and heavy metals, were identified from these 18 AGEs. A total of 10 β -lactamase genes were identified from 10 AGEs sequenced herein, and nine of them were captured within class 1 integrons, which were further integrated into ICEs and IMEs with intercellular mobility, and also unit transposons with intracellular mobility. Through this study, we identified for the first time 20 novel MGEs, including four ICEs Tn 6584 , Tn 6585 , Tn 6586 , and Tn 6587 ; three IMEs Tn 6853 , Tn 6854 , and Tn 6878 ; five unit transposons Tn 6846 , Tn 6847 , Tn 6848 , Tn 6849 , and Tn 6883 ; and eight integrons In1795, In1778, In1820, In1784, In1775, In1774, In1789, and In1799. This was also the first report of two resistance gene variants bla CARB-53 and catB3s , and a novel ST3405 isolate of P. aeruginosa. The data presented here denoted that complex transposition and homologous recombination promoted the assembly and integration of AGEs with mosaic structures into P. aeruginosa chromosomes. [ABSTRACT FROM AUTHOR]

This study investigated the improvement and safety of intrathecal meropenem and vancomycin in the treatment of postoperative intracranial infection in patients with severe traumatic brain injury (STBI). A retrospective analysis was performed on 86 patients with intracranial infections after cranial trauma operation in Tai'an Traditional Chinese Medicine Hospital and Affiliated Hospital of Taishan Medical University from May 2004 to June 2017. The patients were divided into the control group (43 patients) and the experimental group (43 patients) according to the treatment. Patients in the control group were intravenously infused with vancomycin hydrochloride (1.0 g, Q12H) and meropenem (2.0 g, Q8H). After lumbar cistern drainage was performed for the release of cerebrospinal fluid (CSF), patients in the experimental group were slowly given vancomycin 20 mg. After the tube was flushed with 2 ml of 0.9% sodium chloride injection, the patients were slowly given meropenem 20 mg, bid. The clinical efficacy, cure time and treatment cost of patients in the two groups were observed. The adverse reactions and sequelae after 6 months of treatment were recorded. The response rate (RR) of patients in the experimental group was significantly higher than that in the control group (P<0.05). The cure time of patients in the experimental group was significantly lower than that in the control group (P<0.05). The treatment cost of patients in the experimental group was significantly lower than that in the control group (P<0.05). The incidence of adverse reactions of patients, incidence of sequelae of patients in the experimental group was significantly lower than that in the control group (P<0.05). Intrathecal meropenem and vancomycin is more effective than intravenous administration in the treatment of intracranial infection after craniotomy. It can significantly shorten the treatment time and reduce the treatment cost, with better safety. [ABSTRACT FROM AUTHOR]

Summary: Porcine Pegivirus (PPgV) and Atypical Porcine Pestivirus (APPV) are two recently identified porcine viruses. In this study, the identification of two viruses by metagenomic sequencing, and a duplex semi‐quantitative RT‐PCR was developed to detect these pathogens simultaneously. The PPgV strain Minnesota‐1/2016 had a 95.5%–96.3% nucleotide identity and clustered with the recently identified US PPgV strains, which is a distant clade from the German PPgV strains. The APPV strain Minnesota‐1/2016 shared an 87.3%–92.0% nucleotide identity with the other global APPV strains identity but only shared an 82.8%–83.0% nucleotide identity with clade II consisting of strain identified in China. Detection of both PPgV and APPV was 9.0% of the diagnostic cases. Co‐infection of PPgV and APPV was identified in 7.5% of the diagnostic cases. The occurrence and genetic characterization of PPgV and APPV further enhance our knowledge regarding these new pathogens in the United States. [ABSTRACT FROM AUTHOR]

Haemophilus parasuis (H. parasuis) is a kind of opportunistic pathogen of the upper respiratory tract of piglets. Under certain circumstances, virulent strains can breach the mucosal barrier and enter the bloodstream, causing severe Glässer's disease. Many virulence factors are found to be related to the pathogenicity of H. parasuis strain, but the pathogenic mechanism remains unclear. LuxS/AI-2, as a kind of very important quorum sensing system, affects the growth characteristics, biofilm formation, antibiotic production, virulence, and metabolism of different strains. In order to investigate the effect of luxS/AI-2 quorum sensing system on the virulence of H. parasuis , a deletion mutant strain (ΔluxS) and complemented strain (C-luxS) were constructed and characterized. The results showed that the luxS gene participated in regulating and controlling stress resistance, biofilm formation and virulence. Compared with wild-type strain, ΔluxS strain decreased the production of AI-2 molecules and the tolerance toward oxidative stress and heat shock, and it reduced the abilities of autoagglutination, hemagglutination, and adherence, whereas it increased the abilities to form biofilm in vitro. In vivo experiments showed that ΔluxS strain attenuated its virulence about 10-folds and significantly decreased its tissue burden of bacteria in mice, compared with the wild-type strain. Taken together, the luxS/AI-2 quorum sensing system in H. parasuis not only plays an important role in growth and biofilm formation, but also affects the pathogenicity of H. parasuis. [ABSTRACT FROM AUTHOR]

The emergence of antibiotic-resistant Aeromonas strains in clinical settings has presented an escalating burden on human and public health. The dissemination of antibiotic resistance in Aeromonas is predominantly facilitated by chromosome-borne accessory genetic elements, although the existing literature on this subject remains limited. Hence, the primary objective of this study is to comprehensively investigate the genomic characteristics of chromosome-borne accessory genetic elements in Aeromonas. Moreover, the study aims to uncover novel genetic environments associated with antibiotic resistance on these elements. Aeromonas were screened from nonduplicated strains collected from two tertiary hospitals in China. Complete sequencing and population genetics analysis were performed. BLAST analysis was employed to identify related elements. All newly identified elements were subjected to detailed sequence annotation, dissection, and comparison. We identified and newly designated 19 chromosomal elements, including 18 integrative and mobilizable elements (IMEs) that could be classified into four categories: Tn6737-related, Tn6836-related, Tn6840-related, and Tn6844a-related IMEs. Each class exhibited a distinct pattern in the types of resistance genes carried by the IMEs. Several novel antibiotic resistance genetic environments were uncovered in these elements. Notably, we report the first identification of the bla OXA-10 gene and bla VEB-1 gene in clinical A. veronii genome, the first presence of a tetA(E)–tetR(E) resistance gene environment within the backbone region in IMEs, and a new mcr-3.15 resistance gene environment. The implications of these findings are substantial, as they provide new insights into the evolution, structure, and dissemination of chromosomal-borne accessory elements. [ABSTRACT FROM AUTHOR]

Rotavirus B (RVB) is an important swine pathogen, but control and prevention strategies are limited without an available vaccine. To develop a subunit RVB vaccine with maximal effect, we characterized the amino acid sequence variability and predicted antigenicity of RVB viral protein 7 (VP7), a major neutralizing antibody target, from clinically infected pigs in the United States and Canada. We identified genotype-specific antigenic sites that may be antibody neutralization targets. While some antigenic sites had high amino acid functional group diversity, nine antigenic sites were completely conserved. Analysis of nucleotide substitution rates at amino acid sites (dN/dS) suggested that negative selection appeared to be playing a larger role in the evolution of the identified antigenic sites when compared to positive selection, and was identified in six of the nine conserved antigenic sites. These results identified important characteristics of RVB VP7 variability and evolution and suggest antigenic residues on RVB VP7 that are negatively selected and highly conserved may be good candidate regions to include in a subunit vaccine design due to their tendency to remain stable. [ABSTRACT FROM AUTHOR]