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BACKGROUND: Adrenomedullin (ADM) is a regulatory peptide with many biological actions, but little is known about its role in patients with COPD exacerbation. The purpose of this study was to evaluate the diagnostic and prognostic value of plasma ADM levels on hospital admission in patients with COPD exacerbation. METHODS: Consecutive subjects admitted to the hospital for COPD exacerbation were included and were followed up for 1 y; in addition, subjects with stable COPD from an out-patient clinic and healthy volunteers were recruited as controls. RESULTS: Compared with healthy subjects (145 pg/mL [interquartile range {IQR} 103-290 pg/mL]), plasma ADM levels were significantly higher in subjects with COPD exacerbation (270 pg/mL [IQR 170-510 pg/mL], P = .001) and in subjects with stable COPD (400 pg/mL [IQR 210-525 pg/mL], P < .001). In subjects with COPD exacerbation, ADM levels were significantly elevated during exacerbation (560 pg/mL [IQR 495-630 pg/mL]) compared with the recovery phase (470 pg/mL [IQR 393-553 pg/mL], P = .01) and the stable phase (200 pg/mL [IQR 143-308 pg/mL], P < .001). In receiver operating characteristic analysis, in subjects with COPD exacerbation, ADM had high diagnostic accuracy in differentiating between exacerbation and the stable phase (area under the curve 0.97, 95% Cl 0.93-1.02, P < .001). In Cox regression analysis, plasma ADM was not independently associated with 1-y survival (P = .97), but it could accurately predicted the need for ICU care (hazard ratio 1.37, 95% Cl 1.09-1.72, P = .008). CONCLUSIONS: Plasma ADM is a valuable biomarker to confirm COPD exacerbation; furthermore, plasma ADM independently predicts the need of ICU care, although it is not associated with long-term mortality in patients with COPD exacerbation. [ABSTRACT FROM AUTHOR]

Abstract Background Optimum early postnatal growth is critical for early and later health of preterm infants. Postnatal length and weight growth velocities and their associated perinatal factors in healthy late preterm infants without restriction of neonatal complications and nutritional problems have not been widely studied. Methods As part of ongoing longitudinal follow-up study of growth and development of preterm infants in Shandong Qianfoshan Hospital in China, 599 healthy late preterm infants without neonatal complications and nutritional problems were sampled from 795 preterm infants born in January 2014 to April 2017. Perinatal factors, growth parameters, growth velocities(ΔLengthZ and ΔWeightZ: Z-score changes of length and weight) during birth and term-corrected age were documented. Associated variables of growth velocities were analyzed by bivariate and multivariate regression analyses. Adjusted ΔLengthZ and ΔWeightZ were compared between/among subgroups of associated variables using analysis of covariance. Catch-up growth were defined as ΔLengthZ or ΔWeightZ > 0.67. Results The mean ΔLengthZ and ΔWeightZ were 0.28, 0.65, respectively. Catch-up growth of length and weight was ubiquitous(30.7, 46.2%, respectively). Faster length growth velocity was associated with male, larger postmenstrual age(PMA) at birth, younger mother and larger PMA at visit; Faster weight growth velocity was associated with male, unfavorable intrauterine growth status defined by birth weight percentile(Small-for-Gestational-Age(P90)), twin and larger PMA at visit. When adjusted for associated co-variables, weight catch-up growth existed in subgroups of 36 weeks PMA at birth, male, twin and SGA, while AGA almost reached this standard with mean adjusted ΔWeightZ as 0.66. Although none of these subgroups got length catch-up growth standard, infants of 36 weeks PMA at birth had statistically rapider length growth velocity than 34 and 35 weeks PMA at birth subgroups(mean adjusted ΔLengthZs of 34, 35 and 36 weeks subgroups: 0.10, 0.22, 0.38, respectively). Conclusions Postnatal length and weight growth velocities of healthy late preterm infants from birth to term-corrected age were much superior than that of Fenton reference, especially for weight, with ubiquitous catch-up growth. Different associated factors for length and weight growth signified the necessity of constructing more detailed growth standards by specific stratification for associated factors.

The solvent extraction, complexing ability, and basicity of tetradentate N-donor 2,9-bis(5,5,8,8-tetramethyl-5,6,7,8-tetrahydro-1,2,4-benzotriazin-3-yl)-1,10-phenanthroline (CyMe4-BT- Phen) and its derivatives functionalized by Br, hydroxyphenyl, nitryl were discussed and compared. It was demonstrated that four BTPhen ligands are able to selectively extract Am(lll) over Eu(lll). It was notable that the distribution ratio of 5-nitryl-CyMe4-BTPhen for Eu(lll) was suppressed under 0.02, which was much lower compared to DEu(lll) = 1 by CyMe4-BTPhen. The analysis of the effect of the substituent on the affinity to lanthanides was conducted by UV/vis and fluorescence spectroscopic titration. The stability constants of various ligands with Eu(lll) were obtained by fitting titration curve. Additionally, the basicity of various ligands was determined to be 3.1 ± 0.1, 2.3 ± 0.2, 0.9 ± 0.2, 0.5 ± 0.1 by NMR in the media of CD3OD with the addition of DClO4. The basicity of ligands follows the order of L1 > L2 > L3 > L4, indicating the tendency of protonation decreases with the electron-withdrawing ability increase.

FeCrNi/CBN cored wire is prepared by use of the pull-type flux cored wire machine (FCWM50 type), FeCrNi/CBN composite coating is made by high velocity arc spraying. The special properties of the composite coating can be improved by adding Cr, Ni and small amounts of rare earth elements to adjust the coating composition. The Tribological properties of FeCrNi/CBN composite coating with high velocity arc spraying is studied. Images and components and cross-section microstructure of coatings are analyzed by means of SEM, and EDS, etc. This research indicated that FeCrNi/CBN composite coatings have typical layered structure feature and high bond strength and hardness. Friction of coatings at near room temperature or higher has “Run-up” period. With the increase of temperature, friction coefficient of coatings becomes low and wearing capacity of coatings high. The adding of CBN powder highly improved the wearing capacity of coatings. Keywords: FeCrNi/CBN, Tribological properties, Structure feature, Wearing capacity

An efficient asymmetric organocatalyst was developed for the direct aldol reaction between ketones and aldehydes to afford ?-hydroxy ketones in high stereoselectivity ( ANTI/ SYN up to 92:8, ee up to >99%). The key of the success was the use of activated molecular sieves (4 ? MS), which acted as a water scavenger. The influence of additives such as water or different types of molecular sieves on the reactivity and stereoselectivity of the reaction was also studied. [ABSTRACT FROM AUTHOR]

Abstract  In this letter, MnO2-doped (Bi0.5Na0.5)0.94Ba0.06TiO3 (BNBT-6) lead-free piezoelectric ceramics were synthesized by solid state reaction, and the microstructure and electrical properties of the ceramics were investigated. X-ray diffraction (XRD) reveals that all specimens take on single perovskite type structure, and the diffraction peaks shift to a large angle as the MnO2 addition increases. Scanning electron microscopy shows that the grain sizes increases, and then decreases with increasing the MnO2 content. The experiment results indicate that the electrical properties of ceramics are significantly influenced by the MnO2 content, and the ceramics with homogeneous microstructure and excellent electrical properties are obtained with addition of 0.3 wt% MnO2 and sintered at 1160°C. The piezoelectric constant (d33), the electromechanical coupling factor (k p ), the dissipation factor (tan δ) and the dielectric constant (ɛ r ) reach 160 pC/N, 0.29, 0.026 and 879, respectively. These excellent properties indicate that the MnO2-doped BNBT-6 ceramics can be used for actuators. [ABSTRACT FROM AUTHOR]

Liangyoupeijiu is a super high-yield hybrid rice. Despite its advantages with respect to yield and grain quality, it is sensitive to cold, which keeps it from being widely cultivated. We subjected Liangyoupeijiu seedlings to 4°C cold treatment, then extracted the leaf proteins. After 2-D gel electrophoresis separation and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry analysis, a series of differentially displayed proteins were identified. Some metabolism-associated proteins were found among the downregulated proteins, such as carbamoyl phosphate synthetase, transketolase 1, dihydrolipoamide dehydrogenase and glyceraldehyde 3-phosphate dehydrogenase. The upregulated proteins included both stress-resistance proteins such as nucleoside diphosphate kinase I and proteins that are negative for rice growth, such as FtsH-like protein, plastid fusion and/or translocation factor (Pftf) and actin. Our results indicate that cold may inhibit Liangyoupeijiu growth through decreasing metabolic activity and damaging cell structure. (Managing editor: Li-Hui Zhao) [ABSTRACT FROM AUTHOR]

Objective: To explore the clinical manifestation, diagnosis, therapy, and mechanism of hemichorea associated with non-ketotic hyperglycemia (HC-NH) so as to enhance awareness and avoid misdiagnosis or missed diagnosis of the disease.Methods: A case of HC-NH was reported and reviewed in terms of the clinical features, diagnosis and treatment.Results: Hemichorea associated with non-ketotic hyperglycemia is a rare complication of diabetes mellitus, which is commonly seen in elderly women with poorly-controlled diabetes. The condition is characterized by non-ketotic hyperglycemia, unilateral involuntary choreiform movements, and contralateral basal ganglia hyper-intensity by T1-weighted MR imaging or high density on CT scans. Blood glucose control is the basal treatment, in combination with dopamine receptor antagonists and benzodiazepine sedative, in controlling hemichorea.Conclusion: In clinical practice, the possibility of unilateral chorea should be considered for diabetic patients with poor blood glucose control.

AIM: To study the clinical value of non-steroidal anti-inflammatory drug in adjuvant treatment of intravitreal triamcinolone acetonide(IVTA)for macular edema caused by retinal vein occlusion(RVO). METHODS: Forty-eight eyes in 48 patients were randomly divided into trial and control group(24 eyes each)in this prospective study. In the trial group, additional pranoprofen drops was administered from 1d before IVTA to 30d after injection. Central foveal thickness(CFT)was measured with optical coherence tomography(OCT). Available documents of best corrected visual acuity(BCVA), CFT, intraocular pressure and complications pre- and post-injection at 3d, 1,2wk, 1 and 3mo were evaluated. RESULTS: After IVTA, BCVA was improved in both groups at different levels; but there was no statistically significant between two groups at each time point(P>0.05). The CFT values were 629±43μm vs 605±57μm before IVTA in the trail vs control groups(P>0.05). The values were 432±74μm vs 511±32μm(t=7.533, Pvs 379±29μm(t=13.212, Pvs control groups at 1 and 3mo after IVTA, respectively. Ocular hypertension occurred in 5 eyes after injection in trail group, and was controlled with anti-glaucoma medication and one eye with filtration surgery. Progression of cataract was noted in 3 of 35 phakic eyes and cataract surgery was performed in 2 eyes at 4-12mo after injection in trail group. Progression of cataract was noted in 4 eyes and cataract surgery was performed in 2 eyes at 4-12mo after injection in control group. No retinal detachment and endophthalmitis happened during the whole period of follow-up.CONCLUSION: Application of non-steroidal anti-inflammatory eye drops in perioperative period can be useful to improve the outcome of IVTA for macular edema, which needs further evaluation.

Objective: Pelvic abscess during pregnancy is an uncommon complication, but can lead to adverse perinatal outcomes during pregnancy. Case report: We present a patient who developed rupture of a tubo-ovarian abscess during pregnancy following in vitro fertilization and embryo transfer. Thirty-eight reported cases are reviewed, and transvaginal oocyte retrieval, genital tract infections, endometrioma, and previous pelvic surgery are considered as risk factors for pelvic abscess during pregnancy. Conclusion: Prolonging gestational duration when an infection situation is allowed is the principle of treatment.

By means of the full quantum theory,the conditions of generating a periodical quantum echo in the two-photon channel of a atom bit with arbitrary (pure or mixed) initial states was investigated,in coherent light field.Having studied the effects both the atom bit initial state and the surroundings parameter on its fidelity evolution,respectively,the parameter for control the periodical quantum echo of the atom bit was got and discuss its physical characters was discussed,that may be as a possible theoretical basis to the realization of a high fidelity output of quantum information.

The structure evolution and origin of ultrahigh dielectric properties have been investigated in the low temperature range from 300 K to 5 K for [001]-oriented 0.68Pb(Mg1/3Nb2/3)O3–0.33PbTiO3 (PMN–33PT) crystal. The experimental results reveal that a short-range ordered monoclinic MA is the dominant phase at ambient temperature. As the temperature drops below 270 K, the MA transforms into monoclinic MC, and the MC remains stable until 5 K. Although no phase transition occurs from 5 K to 245 K, polar nanoregions (PNRs) display visible changes. The instability of PNRs is suggested as responsible for the low temperature relaxation. The ultrahigh dielectric constant at room temperature is associated with the instability of local structure and phase transition. Our research provides an insight into the design of high-performance ferroelectric materials. [ABSTRACT FROM AUTHOR]

Coupled slow waves, slow acoustic waves, and electromagnetic waves are simultaneously achieved based on a piezoelectric material, in which a line defect is created within a honeycomb lattice array of cylindrical holes etched in a LiNbO slab. Finite element simulations in frequency domain and time domain demonstrate that a highly localized slow mode is obtained in the defect. Owing to the piezoelectricity of LiNbO, acoustic and electromagnetic waves are coupled with each other and transmit along the line defect. Therefore, in addition to a slow acoustic wave, an electromagnetic wave with a group velocity even lower than conventional acoustic waves is achieved. [ABSTRACT FROM AUTHOR]

To block sound, i.e., the vibration of air, most insulators are based on sealed structures and prevent the flow of the air. In this research, an acoustic metamaterial adopting side structures, loops, and labyrinths, arranged along a main tube, is presented. By combining the accurately designed side structures, an extremely wide forbidden band with a low cut-off frequency of 80 Hz is produced, which demonstrates a powerful low-frequency and wide-band sound insulation ability. Moreover, by virtue of the bypass arrangement, the metamaterial is based on an open structure, and thus air flow is allowed while acoustic waves can be insulated. [ABSTRACT FROM AUTHOR]

Adeno-associated virus (AAV) is a human parvovirus with defects and no disease.AAV vector, as an ideal carrier for the transduction of target genes, has certain advantages in long-term gene correction and gene therapy by transferring foreign bases into cells by using the virus's capacity to infect cells.Due to its advantages of extensive host, strong safety and continuous expression of foreign genes, AAV has been used in gene therapy for a variety of tumor.

Abnormal expression of GDNF (glial cell line-derived neurotrophic factor) and its receptor(RET) are associated with the emergence and development of tumors in the digestive system. GDNF and RET are associated with peripheral nerve invasion with a dose-dependent manner in pancreatic cancer, while RET(-) cancer cells lose the ability to invade and destroy nerves. RET mutations promote the proliferation, migration and survival of colon cancer cells, and are associated with poor prognosis of colon cancer patients. GDNF can promote the angiogenesis of liver cancer tissues independently of vasogenic growth factor, providing sufficient nutrition for the growth and invasion of tumor cells. Methylation of the GFR 3 promoter was found in gastric cancer, and the degree of methylation was negatively related to postoperative survival of patients.

Highly reliable embedded systems have been widely applied in the fields of aerospace, nuclear power, high-speed rail, etc., which are related to security and economic development. The reliability of the power supply directly influences the security of the embedded system, and has been the research focus of numerous electronic information and energy studies. The degradation of power modules occupies a dominant position among the key factors affecting the power supply reliability. How to dynamically determine the degradation state and forecast the remaining useful life of working power modules is critical. Therefore, an online non-intrusive method of obtaining the degradation state of MOSFETs based on the Volterra series is proposed. It uses the self-driving signal of MOSFETs as a non-intrusive incentive, and extracts the degradation characteristics of MOSFETs by the frequency-domain kernel of the Volterra series. Experimental results show that the identification achieved by the method agrees well with the theoretical analysis. [ABSTRACT FROM AUTHOR]

In this article, we explored systematically the spore morphology of Pteridaceae by observation of the species distributed in Shandong Province using scanning electron microscopy (SEM). The results showed that the spore morphology of all the species in the family is tetrahedral and trilete. The characters of spore ornamentation are intraspecies stable, but significantly different among species and genera. Spore morphology is significant in exploring the phylogenetic relationships of Pteridaceae as well as in generic and specific delimitations., (© 2021 Wiley Periodicals LLC.)

Aim: To investigate the existence and clinical significance of hepatitis C virus (HCV) RNA in the serum and peripheral blood mononuclear cells (PBMC) of patients with hepatitis C., Methods: HCV RNA was detected by nested polymerase chain reaction (Nested PCR) in serum and in PBMC of 46 patients with acute hepatitis C (AHC) and in 42 patients with chronic hepatitis C (CHC)., Results: The positive rate of HCV RNA in PBMC of patients with CHC was markedly higher than that of patients with AHC (P < 0.01). The positive rates of HCV RNA in serum of patients with AHC and CHC and in PBMC of patients with CHC were significantly higher than those of anti-HCV positive patients with normal alanine aminotransferase (ALT) levels (P < 0.01). HCV RNA was negative in the serum of two patients, but could be detected in PBMC. In 12 patients, anti HCV was negative while HCV RNA was positive in serum., Conclusion: (1) detection of serum HCV RNA by nested PCR might be helpful in the early diagnosis of anti-HCV negative hepatitis C; (2) liver damage in patients with hepatitis C might be correlated with HCV-viremia; (3) infection of PBMC by HCV might play an important role in chronic liver damage in patients with HCV and in the chronicity of its clinical course; and (4) PBMC might be considered as a "reservoir" for HCV.