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Low molecular weight polycyclic aromatic hydrocarbons (LPAHs) are widely present in the environment which poses a serious threat to human health. However, current preprocessing methods in detection are complicated. In this study, a method for rapid sampling and determination of LPAHs in the air was established using a needle trap device coupled with gas chromatography–mass spectrometry. The experimental parameters for NTD-GC-MS were optimized. This method has a linear calibration range from 10 to 1000 ng/L with correlation coefficients (R2) ≥ 0.990. The limits of detection and limits of quantification were from 0.40 to 0.55 ng/L and 1.33 to 1.82 ng/L, respectively. The recoveries were between 85.63% and 106.6%, and the relative standard deviations were below 12.34%. The method was applied to the determination of LPAHs in a smoking room and an auto-shop paint booth. In the former, the only detected LPAH was naphthalene, for which the highest concentration in a day was 471.4 ± 102.1 ng/L. In the paint booth, the highest concentrations of acenaphthene and fluorene were 203.5 ± 32.15 and 184.0 ± 29.64 ng/L, respectively. The results are meaningful for the occupationally exposed population and those suffering from secondhand smoke. The results show that NTD provides a fast and accurate sampling technology for volatile organic compounds from gases.

ObjectiveThe aim of this study was to assess the diagnostic performance of radiomics-based MRI in predicting microvascular invasion (MVI) in hepatocellular carcinoma (HCC).MethodThe databases of PubMed, Cochrane library, Embase, Web of Science, Ovid MEDLINE, Springer, and Science Direct were searched for original studies from their inception to 20 August 2022. The quality of each study included was assessed according to the Quality Assessment of Diagnostic Accuracy Studies 2 and the radiomics quality score. The pooled sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), and diagnostic odds ratio (DOR) were calculated. The summary receiver operating characteristic (SROC) curve was plotted and the area under the curve (AUC) was calculated to evaluate the diagnostic accuracy. Sensitivity analysis and subgroup analysis were performed to explore the source of the heterogeneity. Deeks’ test was used to assess publication bias. ResultsA total of 15 studies involving 981 patients were included. The pooled sensitivity, specificity, PLR, NLR, DOR, and AUC were 0.79 (95%CI: 0.72–0.85), 0.81 (95%CI: 0.73–0.87), 4.1 (95%CI:2.9–5.9), 0.26 (95%CI: 0.19–0.35), 16 (95%CI: 9–28), and 0.87 (95%CI: 0.84–0.89), respectively. The results showed great heterogeneity among the included studies. Sensitivity analysis indicated that the results of this study were statistically reliable. The results of subgroup analysis showed that hepatocyte-specific contrast media (HSCM) had equivalent sensitivity and equivalent specificity compared to the other set. The least absolute shrinkage and selection operator method had high sensitivity and specificity than other methods, respectively. The investigated area of the region of interest had high specificity compared to the volume of interest. The imaging-to-surgery interval of 15 days had higher sensitivity and slightly low specificity than the others. Deeks’ test indicates that there was no publication bias (P=0.71).ConclusionRadiomics-based MRI has high accuracy in predicting MVI in HCC, and it can be considered as a non-invasive method for assessing MVI in HCC.

Additional file 2. CONSORT 2010 checklist of information to include when reporting a randomised trial.

Additional file 1: Table 1. Individual plasmaconcentration-time data of Voriconazole test formulation in the 4 mg/kg group(ng/ml). Table 2. Individual plasma concentration-time data of Voriconazole reference formulation in the 4 mg/kg group (ng/ml). Table 3. Individual plasma concentration-time data of Voriconazole test formulation in the 6 mg/kg group (ng/ml). Table 4. Individual plasma concentration-time data of Voriconazole reference formulation in the 6 mg/kg group (ng/ml).

The current acupuncture's treatment efficacy for FD rely exclusively on subjective patient reports and not on objective biomarkers.Therefore, multimodal assessment of the brain’s structure, function and biochemical and receptor properties has the potential to provide more objective information about pathophysiology, treatment efficacy and biologically based patient subgroups in these conditions by elucidating the contribution of multiple brain networks to the subjective symptom reports. Indeed, numerous studies examining brain processing of visceral sensations have been published in an attempt to identify biomarkers of FD.

The axial and radial load capacity of axial hybrid magnetic bearing (HMB) is critical for the magnetic levitation system. In this paper, the effect of permanent magnet (PM) position on axial and radial magnetic force and stiffness in axial HMB is investigated. Six different configurations are considered and the equivalent magnetic circuits of HMBs for each configuration is built and studied based on the distribution of magnetic field and magnetic leakage. The dependence of axial and radial magnetic force and stiffness on the axial displacement, radial displacement and control current is calculated and investigated for different configurations. To validate the calculated results, the axial and radial magnetic forces for each configuration are simulated by finite element method. A good agreement between the calculated and simulated results validated the proposed magnetic circuit models.

Donkeys’ gut microbe is critical for their health and adaptation to the environment. Little research has been conducted on the donkey gut microbiome compared with other domestic animals. The Tibetan Plateau is an extreme environment. In this study, 6 Qinghai donkeys (QH) from the Tibetan Plateau and 6 Dezhou donkeys (DZ) were investigated, and the contents of 4 parts—stomach, small intestine, cecum, and rectum—were collected. 16S rRNA sequencing and metagenomic sequencing were used to analyze the composition and diversity of gut microbial communities in donkeys. The results showed that the flora diversity and richness of the hindgut were significantly higher than those of the foregut (p p Bacteroidales were the major contributors to these functions. Our study provides novel insights into the contribution of microbiomes to the adaptive evolution of donkeys.

Typhoon disasters may cause power outages in a large area of users. It is quite important to conduct power outage risk assessment in advance and make adequate preparations for emergency decision-making. Starting from the procedure of risk assessment under typhoon disasters: predicting wind speed, calculating wind-induced failure probability, generating fault set, and calculating failure consequences and risks, this paper summarized methods for wind field model, failure analysis methods, and the manifestations of failure consequences in risk assessment. Then we compared the pros and cons for these methods, respectively. The conclusion is that combining software to process higher-resolution wind speed data and considering random wind field, using data mining statistical models to compute and judge fault status and actively calculating pre-typhoon failure risk will become future trend.

The influence of pre-carbonization of petroleum cokes on the properties of the activated carbon precursors and final carbons activated with KOH was investigated by using TG–DTG, FTIR, XRD, and BET techniques. TG–DTG study revealed the decomposition of volatile species and FTIR analysis identified the presence of C–O, C–O–C, C–O–H and some alkyl species on the surface of the precursors. XRD results indicated that a disorder occurred after the carbonization at 500 °C and an order happened gradually with increasing the temperature. The decreases in the BET surface area and N 2 adsorption capacity coincided with the reduction of the functional species on the precursor surface with the increase of the pre-carbonization temperature. These surface functional species were proposed to play a key role in the porosity development during the KOH activation. First, they reacted with KOH to form the intermediate C–O–K species, then the resultants further reacted with the carbon of the precursor, and finally developed the porous structure. As a result, the surface area and the pore size distribution of the activated carbon can be controlled by optimizing the conditions of the pre-carbonization and activation processes.

A detailed study on a small scale of the effect of phosphatization on the chemistry of marine cobalt-rich ferromanganese crusts supplies useful information for the evaluation and comprehensive utilization of crust mineral resources. Sub-samples from top to bottom of a 10-cm thick sample from the NW Pacific Magellan seamount were taken at 5 mm intervals. The concentration profiles of ore-forming and rare earth elements show that obvious differences exist between young unphosphatized crusts and old phosphatized crusts. In the old crusts Fe, Mn, Si, Al, Zn, Mg, Co, Ni and Cu elements are depleted and Ca, P, Sr, Ba and Pb elements are enriched. The order of depletion is Co > Ni > Mg > Al > Mn > Si > Cu > Zn > Fe, while the order of enrichment is P > Ca > Ba > Pb > Sr. The phosphate mineral controls the concentration variation of the ore-forming elements in crusts and causes loss of the main ore-forming elements such as Co and Ni. The phosphatization also affects the abundance of REEs in the crusts. REEs are more abundant and the content of Ce in old crusts is higher than that in young crusts, however, the pattern of REEs and their fractionation characteristics in new and old crusts are not fundamentally changed. A Y-positive anomaly in old crusts has no relationship to the phosphatization.

Objective: To study the protective and therapeutic antitumor immunity against hepatocellular carcinoma (HCC) with the fixed-tumor vaccine.Methods: A tumor vaccine consisting of fixed tumor cells or fixed tumor fragments combined with sustained-releasers of cytokines and a non-toxic adjuvant was developed. C57BL/6J mice were immunized intra-dermally with the vaccine on day 0 and 7, followed by intrahepatic challenge with live Hepa 1–6 cells.Results: All of 15 nonimmunized control mice developed the hepatoma. Protection of mice immunized with fixed Hepa 1–6 cells and both of IL-2/GM-CSF microspheres or further mixed with TiterMax Gold reached 80% and 87%, respectively. Mass growth of the established tumors, vaccinated twice at 5 mm in diameter, the tumor of control animals continued to grow. However, 7–10 days after the second injection of the tumor vaccine, the tumor growth was suppressed in 9 of 10 mice and then markedly reduced. Complete tumor regression was observed in 60% (6/10) of mice. Splenocytes from the control mice were not able to lyse target Hepa 1–6 cells and other tumor cells. In contrast splenocytes from the vaccinated mice exhibited a 41% lytic activity against the Hepa 1–6 cells tested at an effector/target (E/T) ratio of 5, whereas they did not exhibited such activity against the melanoma cells (B16-F1), Lewis lung carcinoma cells (LLC), renal carcinoma cells (Renca), and bladder carcinoma cells (MBT-2). The cytotoxic activity was inhibited by the treatment with anti-CD3, anti-CD8, and anti-MHC-class I monoclonal antibodies but not with anti-CD4 and anti-MHC-class II antibodies. In the Phase-I clinical trial, vaccination of HCC patients with the autologous vaccine is a well-tolerated treatment and induces fixed tumor fragment-specific immunity.Conclusion: Fixed HCC vaccination elicited protective and therapeutic antitumor immunity against HCC. The tumor vaccine elicited antigen specific CTL response lysis of the target HCC was mediated by the typical MHC-class I restricted CD8+ T cells.

Energy is important for the development of human civilization. As conventional energy exhausts, the development of clean and renewable energy, such as wind and solar becomes ever important to people’s live. The wind power has been harnessed by mankind for a long time and the associated technology is more advanced than other clean energies. Nowadays wind power increasingly attracts interests and its utilization has entered a rapid development stage. There are two types of wind turbines, namely horizontal-axis wind turbine (HAWT) and vertical-axis wind turbine (VAWT). The latter has many advantages, such as low cost, simple-structured blades, convenient installation and maintenance, and the ability to utilize wind from all directions without the need of a steering mechanism. A special VAWT implemented with magnetic suspension and self-pitch blade design will be introduced in this chapter. It not only has the advantages of traditional VAWT, but also the advantages of low threshold starting wind-speed, high wind power efficiency, etc. Discussion in this chapter includes the benefits of applying magnetic bearing technology to the wind turbine. Specifically, the entire wind turbine rotor weight can be supported by magnetic bearings. The friction of the bearings is essentially non-existence. There is no need for bearing lubrication, and the maintenance cost can be reduced. Furthermore, the magnetic suspension technology can eliminate mechanical vibration and reduce noise. Since low friction also reduces starting torque, the magnetic bearings enable producing power at lower wind speed than conventional bearings. The discussion also includes a blade-pitch adjusting technique. Conventional VAWT applies special blade adjusting mechanism which is complicated in structure, costly to fabricate and wastes power. Herein, the blades in a magnetic suspended VAWT are designed to adjust the pitch automatically and do not require any dedicated special devices. The blade pitch is adjusted naturally during rotation for the best windward angle. As a result the blades always produce the maximum thrust wind force improving the wind turbine efficiency. Thus, the magnetically suspended and self-pitched vertical-axis wind turbine will be designed with uncomplicated structure, high efficiency and low cost.

The initial work of a research program for developing an acoustic levitation reactor is described, involving experimental studies on acoustic levitation of particles at ambient temperature. The principal design concept is presented in detail, leading to the construction of a prototype acoustic levitator with multiaxial positioning of the levitated particles. Under control of a resonance tracking system, the levitation chamber could be maintained automatically at resonance while the composition of the gas medium surrounding the particles changed. Test particles ranging from chalk to aluminium, with diameters from 2 to 5 mm and shapes from spheres to disks, were stably levitated for more than 2 h. Factors influencing levitation stability are discussed.

At first, the system simulation was run in one degree of freedom based on the non-linear mathematic model of active magnetic bearing (AMB). That analyzes the effect of the controller parameters to the AMB performance and response waveforms of the axis in different parameters. Further, the motional waveform of the axis in two directions (vertical and horizontal) was simulated for the dynamic performance of the axis in the initial levitation.