Search

Continuity, real-time, and accuracy are the key technical indexes of evaluating comprehensive performance of a strapdown inertial navigation system (SINS). However, Schuler, Foucault, and Earth periodic oscillation errors significantly cut down the real-time accuracy of SINS. A method for oscillation error restriction of SINS based on forecasted time series is proposed by analyzing the characteristics of periodic oscillation errors. The innovative method gains multiple sets of navigation solutions with different phase delays in virtue of the forecasted time series acquired through the measurement data of the inertial measurement unit (IMU). With the help of curve-fitting based on least square method, the forecasted time series is obtained while distinguishing and removing small angular motion interference in the process of initial alignment. Finally, the periodic oscillation errors are restricted on account of the principle of eliminating the periodic oscillation signal with a half-wave delay by mean value. Simulation and test results show that the method has good performance in restricting the Schuler, Foucault, and Earth oscillation errors of SINS. [ABSTRACT FROM AUTHOR]

Parthenogenetic embryonic stem cells ( Pg ES) might advance cell replacement therapies and provide a valuable in vitro model system to study the genomic imprinting. However, the differential potential of Pg ES cells was limited. It could result from relative low heterology of Pg ES cells compared with ES cells from fertilization (f ES), which produce different expression of most imprinted genes. Here, we described the establishment of Pg ES cells by aggregating parthenogenetic embryos at the 8-cell stage (a Pg ES cells), which may increase heterozygy. We found that derivation of a Pg ES cells in association with an increased number of inner cell mass cells by aggregating was more efficient than that of Pg ES cells from a single parthenogenetic blastocyst. The a Pg ES cells have normal karyotype, stain positive for alkaline phosphatase, express high levels of ES cell markers and can differentiate into teratomas composed of the three germ layers. Moreover, compared with Pg ES cells, the more highly upregulated paternally expressed imprinted genes were observed in a Pg ES cells, the same change was not shown in a Pg blastocysts. This suggested that the aggregation induced effect could modify the expression of paternally expressed imprinted genes. Our studies showed that a Pg ES cells, the expression of imprinted genes in which more closely resemble f ES cells than Pg ES cells, would contribute to all organs and avoiding immuno-rejection, which may provide invaluable material for regeneration medicine. [ABSTRACT FROM AUTHOR]

• U-Pb dating of garnets constrain Early Cretaceous Au-Cu skarn mineralization at Yinan. • The pervasive Fe-Au-Cu skarn mineralization and associated magmatism in Luxi District, are products of destruction of lithospheric mantle beneath the North China Craton. • Garnet U-Pb dating may have much wider application in hydrothermal mineralization than currently applied. Several recent studies have shown that garnet U-Pb dating may potentially provide robust constraints on the ages of carbonatite, alkaline magmatism and skarn ore formation. Here we present textural, trace element, and laser ablation inductively coupled plasma mass spectrometry U-Pb isotope data of garnet from the Yinan Au-Cu skarn deposit in Luxi District, eastern North China Craton, to place tight constraints on the timing of mineralization. Three hydrothermal andradite-rich garnet samples (JL-8, THZ-38 and TJ-13) collected respectively from Jinlong, Tonghanzhuang and Gongquan ore segments of the Yinan Au-Cu skarn deposit, contain 2.31–10.36 ppm U and are characterized by flat time-resolved depth profiles for U, indicating that this element is hosted in crystallographic lattice in the garnets. The positive correlation between U and LREEs concentration suggests that the incorporation of U into the garnet is largely controlled by substitution mechanisms. The three garnet samples yield weighted mean 206Pb/238U dates of 127 ± 3 Ma, 127 ± 5 Ma and 126 ± 7 Ma (2σ), respectively. These ages are reproducible within analytical uncertainties and are consistent with a zircon U-Pb age of 129 ± 2 Ma of the ore-related diorite intrusion, and thus, are interpreted as the age of Au-Cu mineralization at Yinan. The results presented here, when combined with existing isotopic age data, demonstrate that Au-Cu skarn mineralization throughout the southeastern Luxi District occurred, coevally, in the Early Cretaceous and is genetically associated with the Tongjing and Jingchang granitic-dioritic complexes. The Au-Cu mineralization and associated magmatism coincide in time with the iron skarn mineralization and associated magmatism (134–126 Ma) across the Luxi District, strongly suggesting a causal link between the district-wide skarn mineralization and pervasive intermediate to felsic magmatism; both are products of destruction of lithospheric mantle beneath the North China Craton. This study confirms that garnet U-Pb dating can be a robust geochronometer for garnet-bearing hydrothermal deposits and can elucidate associated geological processes. [ABSTRACT FROM AUTHOR]

Oxidative stress is a frequently occurring pathophysiological feature of spinal cord injury (SCI) and can result in secondary injury to the spinal cord and skeletal muscle atrophy. Studies have reported that glycine and N-acetylcysteine (GlyNAC) have anti-aging and anti-oxidative stress properties; however, to date, no study has assessed the effect of GlyNAC in the treatment of SCI. In the present work, we established a rat model of SCI and then administered GlyNAC to the animals by gavage at a dose of 200 mg/kg for four consecutive weeks. The BBB scores of the rats were significantly elevated from the first to the eighth week after GlyNAC intervention, suggesting that GlyNAC promoted the recovery of motor function; it also promoted the significant recovery of body weight of the rats. Meanwhile, the 4-week heat pain results also suggested that GlyNAC intervention could promote the recovery of sensory function in rats to some extent. Additionally, after 4 weeks, the levels of glutathione and superoxide dismutase in spinal cord tissues were significantly elevated, whereas that of malondialdehyde was significantly decreased in GlyNAC-treated animals. The gastrocnemius wet weight ratio and total antioxidant capacity were also significantly increased. After 8 weeks, the malondialdehyde level had decreased significantly in spinal cord tissue, while reactive oxygen species accumulation in skeletal muscle had decreased. These findings suggested that GlyNAC can protect spinal cord tissue, delay skeletal muscle atrophy, and promote functional recovery in rats after SCI., (© 2023. The Author(s).)

Skeletal muscle atrophy is a frequent complication after spinal cord injury (SCI) and can influence the recovery of motor function and metabolism in affected patients. Delaying skeletal muscle atrophy can promote functional recovery in SCI rats. In the present study, we investigated whether a combination of body weight support treadmill training (BWSTT) and glycine and N-acetylcysteine (GlyNAC) could exert neuroprotective effects, promote motor function recovery, and delay skeletal muscle atrophy in rats with SCI, and we assessed the therapeutic effects of the double intervention from both a structural and functional viewpoint. We found that, after SCI, rats given GlyNAC alone showed an improvement in Basso-Beattie-Bresnahan (BBB) scores, gait symmetry, and results in the open field test, indicative of improved motor function, while GlyNAC combined with BWSTT was more effective than either treatment alone at ameliorating voluntary motor function in injured rats. Meanwhile, the results of the skeletal muscle myofiber cross-sectional area (CSA), hindlimb grip strength, and acetylcholinesterase (AChE) immunostaining analysis demonstrated that GlyNAC improved the structure and function of the skeletal muscle in rats with SCI and delayed the atrophication of skeletal muscle.

Phosphorus is a key nutrient for all plant species and a limiting factor for grassland ecosystem function. In recent years, in response to the rapid increase of global nitrogen deposition, soil phosphorus contents and phosphatase activities changed to varying degrees in grassland ecosystems. We conducted a meta-analysis to examine the responses of soil pH, total phosphorus (TP), available phosphorus (AP), as well as activities of alkaline phosphatase (AlP) and acid phosphatase (AcP) in soils to nitrogen addition amount, nitrogen type, experimental duration, and sampling depth. The correlation between soil pH and phosphatase response ratio was investigated. The results showed that nitrogen addition significantly reduced soil pH, TP and AlP activity, while significantly increased AcP activity, but had no significant effect on AP. Soil pH and AlP activity significantly decreased under nitrogen addition >5 g·m -2 ·a -1 , and AcP activity significantly increased under high nitrogen addition (>10 g·m -2 ·a -1 ). The contents of TP and AP significantly decreased when nitrogen addition was 5-10 g·m -2 ·a -1 . NH 4 NO 3 treatment significantly reduced soil TP and increased AcP activity, while urea treatment significantly reduced soil pH and AlP activity. Across all nitrogen addition amounts, when the experiment duration was 3 to 10 years, soil TP content and AlP activity were significantly reduced. Soil pH was significantly reduced after three years nitrogen addition, and AcP activitiy was significantly increased after 10 years nitrogen addition. In the 0-10 cm soil layer, the TP content and AlP activity significantly decreased, while the AP content significantly increased. In >10 cm soil layer, the AP content was significantly decreased. The significant negative correlation between soil pH and AcP activity indicated that change in soil pH caused by nitrogen addition may be an important factor for the variation of soil phosphatase activity.

Urease in soil, as the most important enzyme catalyzing urea hydrolysis, plays an important role in nitrogen supply of grassland ecosystems. While the effects of different carbon additions on extracellular urease in grassland soil are well understood, their effects on soil intracellular urease remain unknow. Moreover, whether the responses of intracellular and extracellular urease to carbon additions are consistent need to be clarified. With a field experiment in Hulun Buir grassland of Inner Mongolia, we investigated soil intracellular and extracellular urease activities in chernozem under four treatments, including carbon-free (C 0 ), 250 (C 250 ), and 500 (C 500 ) kg C·hm -2 ·a -1 , using glucose as carbon source. Further, we analyzed their relationships with soil properties. Carbon additions significantly increased soil intracellular urease activity and its ratio to total urease activities and total urease activity, but did not affect soil extracellular urease activities. There was significant positive correlation between soil intracellular urease activity and microbial biomass, suggesting that the increases of soil intracellular urease activities were mainly caused by the increases of microbial biomass. Results of structural equation modeling (SEM) analysis showed that carbon additions indirectly increased soil intracellular urease activities by affecting microbial biomass.

Hepatocellular carcinoma (HCC) is one of the most common cancers worldwide. miR-34 induces changes of its downstream genes, and plays a key role in altering the apoptotic cycle and pathways of downstream cells, and finally influences the development of cancer. We assessed the relationship of the pri-miR-34b/c rs4938723 polymorphism with hepatocellular carcinoma risk in a Chinese population. During the period of January 2014 and December 2015, a total of 164 HCC patients and 305 healthy controls were recruited from the Inner Mongolia People's Hospital. Genotyping of the pri-miR-34b/c rs4938723 was determined using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Using χ 2 test, we observed that HCC patients were likely to have a habit of alcohol consumption (χ 2 = 10.24, P = 0.001) and infect with HBV or HCV (χ 2 = 128.17, P < 0.001). In co-dominant model, the CC genotype of pri-miR-34b/c rs4938723 had a significant higher risk of HCC as compared with the TT genotype, and the corresponding adjusted OR (95% CI) was 4.14 (1.91-9.75). In dominant model, we observed that the TC+CC genotype were associated with an increased risk of HCC in comparison to the TT genotype (OR = 1.67, 95% CI = 1.17-2.55). In recessive model, the CC genotype was correlated with an elevated risk of HCC when compared with the TT+TC genotype (OR = 3.46, 95% CI = 1.62-8.54). The pri-miR-34b/c rs4938723 polymorphism was associated with a higher risk of HCC in the Chinese population examined. Further large-scale and multi-center studies are required to confirm these results.

Pig pluripotent cells may represent an advantageous experimental tool for developing therapeutic application in the human biomedical field. However, it has previously been proven to be difficult to establish from the early embryo and its pluripotency has not been distinctly documented. In recent years, induced pluripotent stem (iPS) cell technology provides a new method of reprogramming somatic cells to pluripotent state. The generation of iPS cells together with or without certain small molecules has become a routine technique. However, the generation of iPS cells from pig embryonic tissues using viral infections together with small molecules has not been reported. Here, we reported the generation of induced pig pluripotent cells (iPPCs) using the iPS technology in combination with valproic acid (VPA). VPA treatment significantly increased the expression of pluripotent genes and played an important role in early reprogramming. We showed that iPPCs resembled pig epiblast cells in their morphology and pluripotent markers, such as OCT4, NANOG, and SSEA1. It had a normal karyotype and could form embryoid bodies, which express three germ layer markers in vitro. In addition, the iPPCs might directly differentiate into neural progenitors after being induced with the retinoic acid and extracellular matrix. Our study established a reasonable method to generate pig pluripotent cells, which might be a new donor cell source for human neural disease therapy.

Assembly system with MCM-41 doped with Yb3+ as a host, and Tb(aspirin) 3phen, which had been heat treated, as an active optical guest, was synthesized at room temperature. The structure and physical properties of the composites were characterized by a combination of different techniques such as XRD, N2 adsorption-desorption and IR, while the photoluminescence properties of the composites were analyzed by PL. Excitation and emission spectra were examined to explore the PL properties of the prepared samples and the relationship between the optical guest and the inorganic host. The present paper reports a new synthesis method called "Direct-Calcination" to avoid the loss of rare earth ions in the process of synthesis. Strong reflections at 2theta = 2.6 attributed to (100) reflection were presented in XRD patterns of both Yb/MCM-41 and Tb(aspirin) 3phen-Yb/MCM-41, which always can be observed for regular, spherical structure of MCM-41 materials, and the inorganic framework order increased after Tb(aspirin) 3phen being incorporated into the channels of Yb/MCM-41. The intensity of the band at 963 cm(-1) decreased in IR spectrum of Yb/MCM-41, relative to that in IR spectrum of MCM-41, implying that Yb3+ had been banded with the framwork. And a sharp band at 1 384 cm(-1) in IR spectrum of Tb(aspirin) 3phen-Yb/MCM-41 also gives the characteristic information about the bands in Tb(aspirin) 3phen-MCM-41. The results from the characterization of PL show that the wide excitation band over 240-375 nm of Tb(aspirin) 3phen is assigned to the carbonyl group n --> pi* transition absorption, benzene ring pi --> pi* transition absorption of aspirin, and phenanthrene absorption of phen. The luminescence intensity of Tb(aspirin) 3phen incorporated into the channels of MCM-41 can be enhanced by heat treating in the synthesis process of Tb(aspirin) 3phen, while the intensity also can further increases by doping Yb3+ in the silicon framework of MCM-41. The luminescence intensity of the assembly system gets to maximum when Yb/Si ratio is 7.579 x 10(-3).

Highly ordered mesoporous material MCM-41A(after calcination) and MCM-41B (before calcination) were synthesized in ethylenediamine (EDA) medium at room temperature, and the rare earth complexes Tb(aspirin)3phen which had been heat treated as an active optical guest was incorporated into the one-dimensional channels of MCM-41A(B). The photoluminescence properties of the organic/inorganic composites Tb(aspirin)3phen-MCM-41A(B) were investigated based on the analyses of excitation and emission spectra to provide information about the relationship between the organic host and the inorganic optical guest. The results from the characterization of PL show that the wide excitation band in the range of 240-375 nm of Tb(aspirin)3 phen is assigned to the carbonyl group n --> pi* transition absorption, benzene ring pi --> pi* transition absorption of aspirin, and phenanthrene absorption of phen. As no excitation band appears in ultraviolet ranges, the characteristic emission peaks of Tb3+ in the emission spectra are related to antenna effect Relative to the excitation band of Tb(aspirin)3phen, the excitation band of Tb(aspirin)3phen-MCM-41B and Tb(aspirin)3phen/MCM-41A splits obviously, and only one narrow excitation peak at 353 nm appears in the excitation spectrum of Tb(aspirin)3 phen-MCM-41A. The excitation bands of Tb(aspirin)3 phen-MCM-41B and Tb (aspirin)3 phen/MCM-41A at short wavelength weakens and disappears gradually, while excitation peaks at long wavelengths is enhanced gradually, and the IL/ILn ratio I, where IL is the emission intensity at 405 nm under 335 nm excitation, and I(Ln) is the emission intensity at 544 nm under 335 nm excitation, also decreases correspondingly. It is suggested that the triplet states and single states of aspirin and phen reduce with different degree after Tb(aspirin)3phen is banded with MCM-41 framework, and the effect of silicon framework on the states of phen is more than that of aspirin. The degree of the effect on the states of organic ligands is in the order of: MCM-41B external surface > MCM-41A external surface > MCM-41A inside surface. In addition, the ratio I also could indicates the degree of the effect of MCM-41 surface lattice field on the ligand energy level and the content of Tb (aspirin)3phen on the MCM-41 surface.

Objective: To establish a method for the determination of gossypol in cotton root bark., Method: Samples were extracted with acetone, and determined on a C18 column with the mobile phase (Acetonitrile-0.2% phosphoric acid, 85:15) and UV-235 nm detector., Result: The recovery rate was 97.6%, RSD 1.59% (n = 5)., Conclusion: This method can be used for the determination of gossypol in cotton root bark and the content of gossypol in three different species has been determined.