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Power system stabilizer (PSS) is widely used to improve power system stability. The current parameter coordination optimization method is easy to fall into the local optimization, to solve the problem and find the optimal parameter combination of PSS, the sample screening method based on the similarity index of power system state (SIPSS) and BP neural network is proposed for global optimization parameters of PSS. The SIPSS screening method uses a similar metric index of the grid state variable as the criterion to screen out the required samples. The BP neural network fits the predicted and expected values of the minimum damping ratio of the system after random fluctuations of PSS parameters under various operating modes to minimize the mean square deviation by fitting the streamlined training samples. Firstly, the SIPSS-BP neural network model is obtained by analyzing the mapping relationship between generator power, node power, branch power, and minimum damping ratio. Then, the sensitivity of the PSS parameters damping ratio is calculated, and the PSS parameter optimization model is established. The optimal adjustment of the PSS parameter is obtained, and the minimum damping ratio is modified to improve the system’s stability. Finally, the minimum damping ratio after correction is obtained. The test results of the SIPSS-BP network with the IEEE 3-machines and 9-nodes show that the method can achieve good prediction accuracy, the parameter optimization effect of PSS can be remarkable, and the stability of the power system has been greatly improved.

The influence of small-signal stability on the safety and stability of the power system is becoming more prominent. A mapping model based on steady-state operation information is established using the sample learning method, which provides a new technical path for the rapid assessment and correction of significant power grid oscillation characteristics. This paper establishes a small signal stability assessment and correction control model based on the Extreme Gradient Boosting (XGBoost) algorithm. Firstly, the XGBoost model is obtained by analyzing the mapping relationship between generator power, node power, branch power, and minimum damping ratio. Then, the sensitivity of the generator damping ratio is calculated, and the objective is to minimize the active power adjustment amount of the generator. The stability constraint and power balance are the constraint conditions to establish the optimization correction model, obtain the optimal adjustment amount, correct the minimum damping ratio, and improve the system’s stability. Finally, the minimum damping ratio after correction is obtained, and the modified damping ratio is estimated by XGBoost algorithm. The performance of the proposed model is verified in IEEE 3-machine 9-node and 10-machine 39-node systems.

The Unit Commitment problem (UC) is a complex mixed-integer nonlinear programming problem, so the main challenge faced by many researchers is obtaining the optimal solution. Therefore, this dissertation proposes a new methodology combining the multi-dimensional firefly algorithm with local search called LS-MFA and utilizes it to solve the UC problem. In addition, adaptive adjustment, tolerance mechanism, and pit-jumping random strategy help to improve the optimal path and simplify the redundant solutions. The experimental work of unit commitment with the output of 10–100 machines in the 24-hour period is carried out in this paper. And it shows that compared with the previous UC artificial intelligence algorithms, the total cost obtained by LS-MFA is less and the results are excellent.

The fusions of receptor tyrosine kinase (RTK) involving anaplastic lymphoma kinase (ALK), c-ros oncogene 1 (ROS1), and neurotrophic receptor tyrosine kinase (NTRK) represent the potential targets of therapeutic intervention for various types of solid tumors. Here, the genomic features of 180 Chinese solid tumor patients with ALK, ROS1, and NTRK fusions by next generation sequencing (NGS) were comprehensively characterized, and the data from 121 patients in Memorial Sloan Kettering Cancer Center (MSKCC) database were used to compare. We found that ALK, ROS1, and NTRK fusions were more common in younger female patients (p

OBJECTIVES: The objective of the study is to describe the association of high-sensitivity C-reactive protein (hsCRP) in patients with severe coronavirus disease-19 (COVID-19) pneumonia and determine the relationship between hsCRP, prognosis, and other factors. METHODS: The hsCRP level and other clinical data of patients with severe COVID-19 pneumonia in Tongji Hospital were retrospectively reviewed. Unpaired t-test and Mann–Whitney test were used to compare difference in data between groups. Spearman analysis was used to analyze the correlation. RESULTS: Fifty-seven patients (25 male [43.9%] and 32 female [56.1%]) were included, and their condition was monitored for 28 days. The baseline hsCRP level was 35.5 ± 81.9 mg/L, and the hsCRP level of 49 patients increased (86.0%). Moreover, 45 (78.9%) patients recovered to ordinary/mild COVID-19 pneumonia and 12 (21.1%) progressed to critical COVID-19 pneumonia or continued having severe pneumonia. In the recovered group, the hsCRP level decreased significantly (P = 0.0023). The hsCRP level in the deteriorated group was significantly higher than that of the recovered group (P = 0.0019 and P = 0.0004). ΔhsCRP was significantly correlated with time from onset (P = 0.0151), prognosis (P = 0.0151), ΔD-dimer level (P = 0.0320), Δwhite blood cell count (P = 0.0018), and Δneutrophil count (P = 0.0061). CONCLUSIONS: Severe COVID-19 pneumonia is crucial to patient prognosis and manifests high hsCRP levels; decreased hsCRP level is associated with improved patient prognosis, but hsCRP level may not increase in patients with deteriorating conditions. Simultaneous increase in hsCRP and D-dimer levels may indicate risk for venous thromboembolism in COVID-19 patients.

Anaplastic lymphoma kinase (ALK) fusion events account for ~3–7% genetic alterations in patients with non-small cell lung cancer (NSCLC). In this study, we identified the ALK fusion patterns and a novel ALK fusion partner in 44 ALK positive NSCLC patients using a customized HapOncoCDx panel, and identified ALK fusion partners. The most common partner is EML4, forming the variant 1 (v1, E13:A20, 18/44), variant 2 (v2, E20:A20, 5/44), and variant 3 (v3, E6:A20, 13/44). Moreover, we detected a new ALK fusion partner HMBOX1. At the mutation level, TP53 is the most frequently mutated gene (24%), followed by ALK (12%) and STED2 (12%). The median tumor mutation burden (TMB) of these samples is 2.29 mutations/Mb, ranging from 0.76 mut/Mb to 16.79 muts/Mb. We further elaborately portrayed the TP53 mutation sites on the peptide sequence of the encoded protein by lollipop. The mutational signature and copy number alterations (CNAs) of the samples were also analyzed. The CNA events were found in 13 (13/44) patients, and the most commonly amplified genes were MDM2 (n = 4/13) and TERT (n = 4/13). Together, these results may guide personalized clinical management of patients with ALK fusion in the era of precision medicine.

In this paper, we report a nitrogen (N) doped zinc oxide (N:ZnO) film grown by the reactive high power impulse magnetron sputtering (HiPIMS) technique on glass substrates, where nitrogen gas (N2) is used as the N source. The proposal is to investigate the influence of process parameters on the alteration of the N:ZnO film from n- to p-type conductivity and the stability of the p-type behavior. It is obtained that the n- or p-type behavior of the as-deposited N:ZnO film is affected by the N2 flow rate, deposition temperature, and inductively coupled plasma (ICP) assistance, of which the ICP assistance had a great impact. It is noticed that, owing to the improved ionization rate of the N2 dopant by ICP, the N:ZnO film almost totally prefers to exhibit p-type behavior. Based on the measurement by temporal resolution optical emission spectroscopy, the components in plasma are obtained and the ion reaction in film growth is confirmed: a high concentration of active N+ in the ICP-assisted plasma reacts with sputtered Zn+ in vapor to form No defect in the p-type N:ZnO film. We then forecast that a stable p-type N:ZnO film can be grown using the HiPIMS technique.

Background. Metagenomic next-generation sequencing (mNGS) has made a revolution in the mode of pathogen identification. We decided to explore the diagnostic value of blood and bronchoalveolar lavage fluid (BALF) as mNGS samples in pneumonia. Methods. We retrospectively reviewed 467 mNGS results and assessed the diagnostic performance of paired blood and BALF mNGS in 39 patients with pneumonia. Results. For bacteria and fungi, 16 patients had culture-confirmed pathogen diagnosis, while 13 patients were culture-negative. BALF mNGS was more sensitive than blood mNGS (81.3% vs. 25.0%, p=0.003), and the specificity in BALF and blood mNGS was not statistically significant different (76.9% vs. 84.6%, p=0.317). For 10 patients without culture test, treatments were changed in 2 patients. For viruses, Epstein-Barr virus was positive in blood mNGS in 9 patients. Human adenovirus was detected in both BALF and blood mNGS in 3 patients. Conclusion. Our study suggests that BALF mNGS is more sensitive than blood mNGS in detecting bacteria and fungi, but blood also has advantages to identify the pathogens of pneumonia, especially for some viruses.

In this paper, we investigate the properties of chromium nitride (CrN) coating prepared using a high power magnetron sputtering (HiPIMS) technique. As a comparison, CrN coating prepared using a direct current magnetron sputtering (DCMS) technique is also studied. The crystal structure, surface and cross-sectional morphologies, and composite properties of the as-deposited CrN coatings are compared by x-ray diffraction, a scanning electron microscope, and a microhardness tester, respectively. It is found that the as-deposited CrN film by HiPIMS grew preferentially on (200) facet when compared with that by DCMS on (111) facet. As a result, the coatings deposited by HiPIMS have a very compact microstructure with high hardness: the microhardness reached 855.9 Hv replacing 501.5 Hv by DCMS. Besides, the inner-stress of CrN films prepared by HiPIMS is also relatively small. After measuring the corrosion resistance, the corrosion current of films prepared by HiPIMS was an order of magnitude smaller than that of CrN films deposited by DCMS. Based on the plasma diagnostics by time resolved optical emission spectroscopy, it is believed that the superior quality of CrN coatings prepared by HiPIMS is because of the ionic reaction between Cr+ and N+, rather than the neutral Cr and N reaction in DCMS during the CrN film growth.

Abstract In this paper, we report the combination of atomic layer deposition (ALD) with hydrothermal techniques to deposit ZnO on electrospun polyamide 6 (PA 6) nanofiber (NF) surface in the purpose of antibacterial application. The micro- and nanostructures of the hierarchical fibers are characterized by field emission scanning electron microscopy (FE-SEM), high-resolution transmission electron microscopy (HRTEM), and scanning transmission electron microscopy (STEM). We find that NFs can grow into “water lily”- and “caterpillar”-like shapes, which depend on the number of ALD cycles and the hydrothermal reaction period. It is believed that the thickness of ZnO seed layer by ALD process and the period in hydrothermal reaction have the same importance in crystalline growth and hierarchical fiber formation. The tests of antibacterial activity demonstrate that the ZnO/PA 6 core-shell composite fabricated by the combination of ALD with hydrothermal are markedly efficient in suppressing bacteria survivorship.

This paper presents the strategy of selective-area growing of a positively-charged layer of Al2O3 and the negatively-charged layer of HfO2 on ion beam track-etched polyethylene terephthalate (PET) nanotubes through the thermal atomic layer deposition (T-ALD) technique. We used the self-assembled monolayer of octadecyl trichlorosilane (OTS-SAMs) on the surface to serve as a passivation layer and then selectively deposited the Al2O3 and HfO2 in the nanotubes. The influence of the dipping time of the substrates in the OTS solution and the experimental conditions on the roughness and the thickness of the OTS monolayer have been investigated. X-ray photoelectron spectroscopy (XPS) was used to analyze the composition of the ALD Al2O3 and HfO2 films. Atomic force microscope (AFM) and scanning electron microscope (SEM) were employed to study the morphologies before and after the ALD of Al2O3 and HfO2. The I-V characteristics of the film confirmed the surface charge polarities in the nanotubes, i.e. the positively-charged Al2O3 and negatively-charged HfO2, in the electrically-neutral solution. The results will aid surface modification and functionalization of PET by nanotubes.

In this paper, we report on polyethylene (PE) film modified by atmospheric dielectric barrier discharge (DBD) plasma prior to the deposition of SiOx coating to improve its barrier properties. Three kinds of monomers: allylamine, acrylic acid, and ethanol, are used to modify the PE surface. For comparison, Ar and O2 plasma pre-treatments are also performed. It is found that with the addition of a monomer in the Ar DBD plasma, the grafted active groups on PE surfaces lead to dense, pinhole-free growth of the SiOx film. The oxygen transmission rate (OTR) decreases from 700 cc/m2·day·atm. for the pristine to ca. 70 cc/m2·day·atm. for the pretreatment-coated PE, which is more than a 10-fold reduction. The relationship between the grafted monomer and the great decrease of OTR is then explored via chemical composition by attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR) and via morphology observation by atomic force microscopy (AFM) and scanning electron microscopy (SEM). The results show that the grafted functional groups of -NH2, -COOH and -OH increase the surface energy and promote the nucleation of Si⁻O radicals on polymeric surfaces, and the formation of network and cage structures in SiOx film contributes to the significant improvement of OTR.

Background: Understanding epidemiological characteristics of diabetes in a specific population will potentially benefit prevention and control of diabetes and policy-making. This study aimed to investigate the prevalence and awareness of diabetes, as well as its pharmacological, non-pharmacological and primary care management in Shenzhen, China.Methods: A cross-sectional study was conducted. We employed multistage cluster random sampling methods to select the participants. Face-to-face interview surveys were conducted to collect data. A total of 1676 participants completed the survey.Results: We found that the prevalence of diabetes was 4.8%. The prevalence of impaired fasting blood glucose was 6.0%. The prevalence rates of both diabetes and impaired fasting blood glucose increased with age (P < 0.001), whereas hypertension was strongly associated with diabetes only (odds ratio (OR) = 1.93, 95% confidence interval (CI) 1.15-3.22). The awareness of diabetes was poor (51.9%) and 54.3% of diabetic patients were not being treated pharmacologically. Less than one-third of diabetic patients were undergoing non-pharmacological treatments. Primary care management of diabetes was recorded for only 11.1% of the patients.Conclusions: Although diabetes prevalence in Shenzhen is about a half that of the Chinese average, high prevalence of impaired fasting blood glucose imposes a public health threat and burden to the health care system. Approximately half of the subjects with diabetes are undiagnosed. Our findings highlight the need of public health efforts for primary and secondary prevention, as well as early detection of diabetes. Primary care may be crucial an improved access to medical services and better management of diabetes. [ABSTRACT FROM AUTHOR]

Objectives An understanding of the awareness, treatment and control of hypertension is helpful to guide decision-making regarding interventions to reduce the risk for diseases with hypertension as a key risk factor. This study aimed to estimate the prevalence, awareness, treatment, and control of hypertension in Shenzhen, China. Methods A cross-sectional study was conducted. We employed multistage cluster random sampling methods to select participants. A survey involving face-to-face interviews was conducted to collect the data. A total of 1676 participants finished the survey and formed the final analysis. Results We found that the prevalence of hypertension was 17.6%. The rates of hypertension awareness, treatment and control were 48.8%, 51.4% and 43.2% respectively. Only 6.8% hypertensives were found to be managed by community health centres. Compared with the female participants, the males were found to have higher rates of prevalence (19.7% vs 15.7%; OR 1.47, 95% CI 1.10 to 1.97) and awareness (42.9% vs 38.1%; OR 2.35, 95% CI 1.28 to 4.33), but lower rates of medication treatments (20.5% vs 30.2%; OR 0.83, 95% CI 0.05 to 0.92) and control (12.8% vs 23.0%; OR 0.45, 95% CI 0.21 to 0.96). Migrants were more likely to be aware of hypertension (32.5% vs 44.3%; OR 0.57, 95% CI 0.30 to 0.90), reduce their salt intake (8.8% vs 18.1%; OR 0.40, 95% CI 0.15 to 0.94), and undertake regular monitoring of hypertension (1.3% vs 11.0%; OR 0.14, 95% CI 0.02 to 0.92) when compared with the locals. Conclusions Our study finds that hypertension is an important public health burden in Shenzhen. It implies that strategies need to be developed to improve effective primary care management of hypertension. It also suggests a need to develop gender and household register tailored strategies for the prevention, detection, treatment and control of hypertension. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, a new direct current (DC) plasma source for surface alloying using array-needle-cathode has been designed and manufactured. The array-needle-cathode is used to produce a stable abnormal glow discharge plasma in a rectangular chamber. During the surface alloying process, it is noticed that the discharge modes severely influenced the plasma parameters including electron density (Ne) and electron temperature (Te). The Te obtained by optical emission spectrometry (OES) through the comparison of the relative intensity of N in 3919Å and 3995Å is between 1.44eV and 5.40eV. The distribution and fluctuation of Te in the two-dimensional planar are revealed by analysis of digital camera images. It is concluded that the discharge by the array- needle-cathode is a kind of new plasma source which can generate stable plasma with a high electron temperature applicable for surface alloying. Lastly, with this array-needle-cathode plasma source (ANCPS), W-Mo-N alloyed layer on Ti alloy is explored in this paper. [Copyright &y& Elsevier]

A radio frequency (RF) pulsed plasma polymerized allylamine (PPPAA) film as an adhesion layer to adsorb DNA probe and then hybridize with a complementary or a mismatch DNA target is investigated in this paper. The possible application of plasma polymerization film as an adhesion layer for DNA hybridization assay is evaluated by DNA hybridization reactions. It was found, by surface plasmon enhanced fluorescence spectroscopy (SPFS), that the DNA hybridization reactions in phosphate buffered saline (PBS) solution can be remarkably revealed by fluorescence signals, but it heavily depends on the solution conditions. The influence of the solution pH value and the ionic strength on the PPPAA film thickness and adsorption is explored in detail. [ABSTRACT FROM AUTHOR]

The patterns in radio-frequency dielectric barrier discharge (RF DBD) are studied at atmospheric pressure of argon (Ar) or helium (He) mixed with nitrogen (N2) gas. When a small amount of N2 is mixed with He or Ar gas, discharge patterns are formed. In a N2/He gas mixture, besides the filament discharge that forms patterns, a glow background discharge is also observed, whereas only the filament discharge forms patterns in a N2/Ar gas mixture. The resolution of the hexagonal pattern as a function of applied power and gas flow rate is then explored. On the basis of spatial–temporal images taken using an intensified charge-coupled device (ICCD), we find that there is no interleaving of two transient hexagon sublattices in N2/Ar or N2/He plasma in RF DBD patterns, which are totally different from those in which surface charges dominated in the mid-frequency DBD plasma. This supports our hypothesis that the bulk charges dominate the pattern formation in RF DBD. [ABSTRACT FROM AUTHOR]

A simple cryptanalysis of the self-shrinking generator with very short keystream for the case of unknown connection polynomial is provided. The expected complexity of this cryptanalysis is 2[SUP1.5L] when the length of the LFSR of the generator is L. [ABSTRACT FROM AUTHOR]