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Background: Determining the source of infection is significant for the treatment of bloodstream infections (BSI). The gold standard of blood infection detection, blood cultures, have low positive rates to meet clinical needs. In this study, we investigated the ability of hybrid capture-based next generation sequencing technology to detect pathogens in peripheral blood samples collected from patients with suspected BSI. Blood cultures and capture sequencing assays were also analyzed against the final clinical diagnoses. Methods: In this study, peripheral blood samples were collected from patients with fever, chills, and suspected BSI at Jinshazhou Hospital of Guangzhou University of Chinese Medicine from March 2023 to January 2024. All samples were tested by three different technologies: plasma capture sequencing technology, white blood cell capture sequencing technology, and blood culture. Relevant clinical diagnostic information was also collected. The performances of the blood cultures were then compared to those of both plasma capture sequencing technology and white blood cell capture sequencing technology. Results: A total of 98 patients were included in this study. The positive rates of probe capture next generation sequencing (NGS technology) in plasma and white blood cells were 81.63% and 65.31%, respectively, which were both significantly higher than that of the blood culture, which was 21.43% (p < 0.001). Taking blood culture as the standard control, the sensitivity and specificity of plasma capture sequencing were 85.71% and 71.43%, respectively, while the sensitivity and specificity of white blood cell sequencing were 76.19% and 81.82%, respectively. Upon final clinical diagnosis, the clinical agreement rates of the blood cultures, plasma capture sequencing, and white blood cell capture sequencing were 39.80%, 83.67%, and 73.47%, respectively. Conclusion: Our study demonstrates the high accuracy of probe capture sequencing technology compared to blood cultures in the identification of pathogenic microorganisms in BSI upon final clinical diagnosis. Among the different sample types, white blood cell samples had a lower clinical compliance rate compared to plasma samples, possibly due to the higher host rate in cell samples, which impairs the sensitivity of pathogen detection. [ABSTRACT FROM AUTHOR]

With the gradual depletion of natural sand due to over-exploitation, alternative building materials, such as manufactured sand aggregate (MSA), have attracted much attention. In order to interpret the evolution of pore structure and fractal characteristics in MSA mortar over long-term water saturation, the 1H low-field nuclear magnetic resonance (LF-NMR) relaxation method was used to investigate the temporal evolution of the pore structure in five single-graded MSA mortars and synthetic-graded mortars with small amplitudes in particle size. MSA presents a fresh rock interface characterized by a scarcity of pores, which significantly reduces the porosity of the mortar. The surface-to-volume ratio (SVR) is employed for characterizing the MSA gradation. Through an analysis of parameters, such as total porosity, pore gradation, pore connectivity, and pore fractal dimension of mortar, a correlation model between pore structure parameters and aggregate SVR is constructed. The fractal characteristics of pores and their variations are discussed under three kinds of pore gradations, and the correlation model between fractal dimension and porosity is established. These results demonstrate the high impermeability and outstanding corrosion resistance of synthetic-graded mortar. The fractal model of the pore structure evolution of MSA mortar has a guiding effect on the pore distribution evolution and engineering permeability evaluation of MSA mortar in engineering. [ABSTRACT FROM AUTHOR]

Greenhouse gas emissions induced by climate change have garnered global attention. Minimizing climate change can be achieved through the reduction of carbon emissions in transportation infrastructure construction and in the production of construction materials. This study aims to calculate carbon emissions in three hypothetical construction scenarios based on the life cycle assessment (LCA) method when a roadway passes across polluted soil at contaminated sites. Three methods are employed to remediate contaminated soil: off-site cement kiln co-processing, on-site ex-situ thermal desorption, and on-site ex-situ solidification/stabilization. Carbon emissions are calculated using the LCA method for each scenario. The baseline carbon emission is estimated for the scenario in which contaminated soil is remediated using the off-site cement kiln co-processing method, and the roadway subgrade is constructed using transported clean soil. In the other two scenarios, contaminated soils are remediated using the on-site ex-situ thermal desorption and solidification/stabilization methods, respectively, and then they are reused as roadway subgrade materials. The LCA analyses demonstrate that the total carbon emission reductions range from 1168.48 to 2379.62 tons per basic unit, corresponding to decreased of 19.31% to 39.33%, respectively, compared to baseline. The reuse of solid waste to replace sand and ordinary Portland cement (OPC) as raw materials in roadway construction reduces carbon emissions by 498.98 tons. Finally, a comparison of carbon emissions between the three scenarios indicates that reducing carbon emissions in the remediation of contaminated soil and reusing solid waste as construction materials are two important methods for achieving overall carbon emission reductions in roadway construction projects. [ABSTRACT FROM AUTHOR]

Due to the damage they have caused to the ozone layer, first-generation refrigerants known as chlorofluorocarbons have been phased out, and second-generation refrigerants known as hydrochlorofluorocarbons are being phased out. Third-generation refrigerants known as hydrofluorocarbons are also being phased out due to their high global warming potential. As successors to the above three generations of refrigerants, hydrofluoroolefins and hydrochlorofluoroolefins were designed and created in laboratories. They have been attracting increasing research interest because they are safe and environmentally friendly. In this paper, various aspects of the recent research on hydrofluoroolefin and hydrochlorofluoroolefin refrigerants, including applications in refrigeration systems and heat pump systems, applications in organic Rankine cycles, flow patterns and heat transfer characteristics, thermophysical properties, persistent degradation product, toxicity, flammability and ignitability, thermal stability and decomposition mechanisms, are reviewed and discussed. The most commonly studied hydrofluoroolefins are still HFO-1234yf and HFO-1234ze(E). HFO-1336mzz(Z) is also worthy of further attention because it may be a suitable replacement for HFC-123. Attempts can be made to establish a dedicated equation of state for commonly used hydrofluoroolefins to better predict the thermodynamic properties. Further studies on the persistent degradation product, toxicity, flammability and ignitability, thermal stability and decomposition mechanism are needed. • Applications of HFOs/HCFOs in refrigeration and heat pump systems are described. • Applications in organic Rankine cycle are introduced. • Flow pattern and heat transfer characteristics are analyzed. • Thermophysical properties are discussed. • Some concerns about HFOs are presented. [ABSTRACT FROM AUTHOR]

This paper investigates the issue of laterally loaded X-section cast-in-place concrete (XCC) pile group in undrained soil and, in particular, evaluates limit lateral resistance (LLR) through finite element limit analysis. Four types of XCC pile groups that are commonly used in practice are selected for discussion here. Both the upper- and lower-bound numerical results for the LLR of the XCC pile groups are presented. The influence of loading direction, pile group shape, and XCC pile cross-sectional shape is evaluated with a series of parametric studies. Design equations are subsequently proposed for computing the LLR of four types of XCC pile groups in undrained soil. [ABSTRACT FROM AUTHOR]

The article discusses the problems with national strategies, driving regional economic development, and evaluating the effectiveness of the Free Trade Zone (FTZ) construction. Topics include expanding the opening up, improving the open economic system, drawing lessons from international experience, and carrying out free trade and production; and emphasizing the high-quality economic growth through optimization and upgrading economic structure.

Summary: In order to capture the influence of the cavity expansion velocity, this paper presents a semianalytical solution for dynamic spherical cavity expansion in modified Cam Clay (MCC) soil. The key problem is solving the six coupled partial differential equations (PDEs) of cavity expansion, in which the dynamic term is considered in the stress equilibrium equation. The similarity transformation technique is used to transform the PDEs into ordinary differential equations (ODEs). Subsequently, the numerical method using the function "ODE45" in MATLAB is selected to solve the ODEs, which allows the stress and excess pore pressure around the expanding spherical cavity wall to be obtained. The proposed semianalytical solution for dynamic spherical cavity expansion was validated by comparting the degenerate solution with the published quasistatic solution for the MCC model. Parametric study was then conducted to capture the influence of the cavity wall velocity on the cavity expansion response. The proposed solution has potential application to geotechnical problems such as dynamic pile driving, the dynamic cone penetration test, and so forth. [ABSTRACT FROM AUTHOR]

Background: The rapid determination of pathogenic agent is very important to clinician for guiding their clinical medication. However, current diagnostic methods are of limitation in many aspects, such as detecting range, time-consuming, specificity and sensitivity. In this report, we apply our new-developing pathogen detection method to clarify that Propionibacterium acnes is the causative agent of a two-year-old boy with juvenile myelomonocytic leukemia presenting clinical symptoms including serious rash and hyperpyrexia while traditional clinical methods of diagnosis fail to detect the pathogenic agent and multiple antimicrobial drugs are almost ineffective Propionibacterium acnes is confirmed to be the infectious agent by quantitative real-time polymerase chain reaction.Case Presentation: After haploidentical hematopoietic stem cell transplantation, a two-year-old boy with juvenile myelomonocytic leukemia presented to a pediatrist in a medical facility with hyperpyrexia and red skin rash which later changed to black skin rash all over his body. Traditional diagnostic assays were unrevealing, and several routine antimicrobial treatments were ineffective, including the vancomycin, meropenem, tobramycin, cefepime and rifampin. In this case, pediatrist resorted to the next-generation sequencing technology for uncovering potential pathogens so as to direct their use of specific drugs against pathogenic bacteria. Therefore, based on the BGISEQ100 (Ion Proton System) which performed sequencing-by-synthesis, with electrochemical detection of synthesis, and each such reaction coupled to its own sensor, which are in turn organized into a massively parallel sensor array on a complementary metal-oxidesemiconductor chip, we detect and identify the potential pathogens. As a result, we detected a significantly higher abundance of skin bacteria Propionibacterium acnes in patient's blood than controls. It had been reported that patients infected by Propionibacterium acnes almost always had history of immunodeficiency, trauma or surgery. Considering this possible cause, antimicrobial treatment was adjusted to target this rare opportunistic pathogen. Fever and black skin rashes were rapidly reduced after administrating specific drugs against Propionibacterium acnes.Conclusion: This case showed our new-developing pathogen detection method was a powerful tool in assisting clinical diagnosis and treatment. And it should be paid more attention to Propionibacterium acnes infection in clinical cases. [ABSTRACT FROM AUTHOR]

By considering the complex networks, the cooperative game based optimal consensus (CGOC) algorithm is proposed to solve the multi-UAV rendezvous problem in the mission area. Firstly, the mathematical description of the rendezvous problem is established, and the solving framework is provided based on the coordination variables and coordination function. It can decrease the transmission of the redundant information and reduce the influence of the limited network on the task. Secondly, the CGOC algorithm is presented for the UAVs in distributed cooperative manner, which can minimize the overall cost of the multi-UAV system. The CGOC control problem and the corresponding solving protocol are given by using the cooperative game theory and sensitivity parameter method. Then, the CGOC method of multi-UAV rendezvous problem is proposed, which focuses on the trajectory control of the platform rather than the path planning. Simulation results are given to demonstrate the effectiveness of the proposed CGOC method under complex network conditions and the benefit on the overall optimality and dynamic response. [ABSTRACT FROM AUTHOR]