The capsular polysaccharides (CPS) of Group B Streptococcus play a crucial role as virulence determinants and are potential candidates for antigenic components in vaccine formulations. Alkaline ...treatments are commonly used to extract polysaccharides owing to their efficiency and cost-effectiveness; however, they may induce the removal of N-acetyl groups from CPS. This study involved re-N-acetylation of CPS Ia to improve its biological functionality. The structural modifications and enhanced antigenicity of CPS Ia were observed after re-N-acetylation. The tetanus toxoid (TT) was conjugated with either partially de-N-acetylated or fully re-N-acetylated CPS. As a result, the conjugate containing re-N-acetylated CPS (IaReN-TT) enhanced the induction of IgG antibody levels and functional antibodies in mice. Both passive and active protection assays substantiated the superior protective efficacy of IaReN-TT, suggesting that the re-N-acetylation of CPS Ia could be a critical step in refining the immunogenic profile of glycoconjugate vaccines.
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•Migmatized rocks are widely distributed within the Jiaobei Terrane.•U–Pb age data reveal a Paleoproterozoic (1860.9–1833.3Ma) partial melting event.•The partial melting event was genetically related ...to MP granulite facies ‘hot’ exhumation of the Jiaobei Terrane.
In the Jiaobei Terrane of the Jiao–Liao–Ji Belt, eastern China, layers and irregular lenses of granitic leucosomes are widely distributed within high-pressure (HP) mafic granulites, medium-pressure (MP) granulites, amphibolites, TTG gneisses, and HP and MP pelitic granulites. The layers and lenses may be parallel to or cross-cut the foliation in the host rocks on different scales, and they show evidence of coalescence and migration in the formation of centimeter- to decimeter-scale segregations. The migmatized rocks extend over an area of at least 120km×75km from Laixi, through Laiyang and Qixia, to SW Yantai. A combined study of mineral inclusions, cathodoluminescence (CL) images, and zircon U–Pb LA–ICP–MS dates provides clear evidence on the nature and timing of the partial melting in these granulite facies metamorphic rocks. Most zircons from the granitic leucosomes are either inherited crystals (igneous or detrital) with distinct overgrowths, or are simply new euhedral crystals. Both the overgrowths and the new crystals commonly exhibit perfect euhedral shapes, pronounced oscillatory zoning, and contain mineral inclusions of Qtz+Kfs+Pl+Ap. In contrast, the inherited cores are rounded or irregular in shape, and exhibit signs of dissolution. These observations suggest that the new zircons are anatectic in origin, and that they crystallized from melts derived from dehydration melting reactions and partial melting of the host granulite-facies rocks. Numerous U–Pb spot analyses of anatectic zircons reveal that the Jiaobei Terrane experienced a major episode of partial melting in the Paleoproterozoic, with crystallization of the melt occurring in two distinct periods from 1860.9±2.2 to 1852.1±2.8Ma, and 1839.9±2.9 to 1833.3±5.3Ma, as represented, respectively, by the magmatic cores and rims of the anatectic zircons. The first age group probably represents the initial crystallization of melts derived from partial melting within the Jiaobei Terrane, while the second age group may represent the completion of migmatization and crystallization of granitic leucosomes. This significant partial melting event was genetically associated with the Paleoproterozoic MP granulite-facies ‘hot’ stage of exhumation of the southwestern part of the Jiao–Liao–Ji Belt, and it induced extensive retrogression of the TTG gneisses and mafic and pelitic granulites, as well as the formation of regional migmatites.
► Hot working behavior of Ti60 alloy was characterized by isothermal compression tests. ► Flow stress of Ti60 decreased with increasing temperature and decreasing strain rate. ► Greater flow ...softening was observed in the α
+
β field compared with that of β field. ► The activation energy was 653 and 183
kJ/mol for α
+
β and β field, respectively. ► Two instable fields should be avoided during the deformation of Ti60 alloy.
Isothermal compressions of near-alpha Ti60 alloy were carried out on a Gleeble-3800 simulator in the temperature range of 960–1110
°C and strain rate range of 0.001–10.0
s
−1. The high-temperature deformation behavior was characterized based on an analysis of the stress–strain behavior, kinetics and processing map. The flow stress behavior revealed greater flow softening in the two-phase field compared with that of single-phase field. In two-phase field, flow softening was caused by break-up and globularization of lamellar α as well as deformation heating during deformation. While in the single-phase field, flow softening was caused by dynamic recovery and recrystallization. Using hyperbolic–sine relationships for the flow stress data, the apparent activation energy was determined to be 653
kJ/mol and 183
kJ/mol for two-phase field and single-phase field, respectively. The processing map exhibited two instability fields: 960–980
°C at 0.3–10
s
−1 and 990–1110
°C at 0.58–10
s
−1. These fields should be avoided due to the flow localization during the deformation of Ti60 alloy.
The class imbalance problem has a huge impact on the performance of diagnostic models. When it occurs, the minority samples are easily ignored by classification models. Besides, the distribution of ...class imbalanced data differs from the actual data distribution, which makes it difficult for classifiers to learn an accurate decision boundary. To tackle the above issues, this article proposes a novel imbalanced data classification method based on weakly supervised learning. First, Bagging algorithm is employed to sample majority data randomly to generate several relatively balanced subsets, which are then used to train several support vector machine (SVM) classifiers. Next, these trained SVM classifiers are adopted to predict the labels of those unlabeled data, and samples that are predicted as minority class are added to the original dataset to reduce the imbalance ratio. The critical idea of this article is to introduce real-world samples into the imbalanced dataset by virtue of weakly supervised learning. In addition, bidirectional gated recurrent units are used to construct a diagnostic model for fault diagnosis, and a new weighted cross-entropy function is proposed as the loss function to reduce the impact of noise. Besides, it also increases the model's attention to the original minority samples. Furthermore, experimental evaluations of the proposed method are conducted on two datasets, i.e., Prognostics and Health Management challenge 2008 and 2010 datasets, and the experimental results demonstrate the effectiveness and superiority of the proposed method.
To enhance the growth performance of
under osmotic stress, mutant XCG001, which tolerates up to 1.5 M NaCl, was isolated through adaptive laboratory evolution (ALE). Comparisons of the transcriptome ...data of mutant XCG001 and the wild-type strain identified
as being associated with osmotic tolerance. In the
overexpression strain (XCG010), the contents of inositol phosphorylceramide (IPC; t18:0/26:0), mannosylinositol phosphorylceramide MIPC; t18:0/22:0(2OH), MIPC (d18:0/22:0), MIPC (d20:0/24:0), mannosyldiinositol phosphorylceramide M(IP)
C; d20:0/26:0, M(IP)
C t18:0/26:0(2OH), and M(IP)
C d20:0/26:0(2OH) increased by 88.3 times, 167 times, 63.3 times, 23.9 times, 27.9 times, 114 times, and 208 times at 1.0 M NaCl, respectively, compared with the corresponding values of the control strain XCG002. As a result, the membrane integrity, cell growth, and cell survival rate of strain XCG010 increased by 24.4% ± 1.0%, 21.9% ± 1.5%, and 22.1% ± 1.1% at 1.0 M NaCl, respectively, compared with the corresponding values of the control strain XCG002 (wild-type strain with a control plasmid). These findings provided a novel strategy for engineering complex sphingolipids to enhance osmotic tolerance.
This study demonstrated a novel strategy for the manipulation of membrane complex sphingolipids to enhance
tolerance to osmotic stress. Elo2, a sphingolipid acyl chain elongase, was related to osmotic tolerance through transcriptome analysis of the wild-type strain and an osmosis-tolerant strain generated from ALE. Overexpression of
increased the content of complex sphingolipid with longer acyl chain; thus, membrane integrity and osmotic tolerance improved.
•Zircons from the Daqingshan–Wulashan mafic rocks record four mafic magmatic events and two high-grade metamorphic events.•Middle- and low-pressure granulite facies mineral inclusions have been ...identified in ca. 2.45Ga and ca. 1.9Ga metamorphic zircons.•The Daqingshan–Wulashan meta-mafic rocks were most likely generated by an orogenic process in an active continental margin arc.
Meta-mafic rocks in the Daqingshan–Wulashan Complex, in the central segment of the Paleoproterozoic Khondalite Belt of the North China Craton, are composed predominantly of garnet-bearing mafic granulites, mafic granulites, and amphibolites. They occur mainly as irregular lenses and as a set of deformed dyke/sill swarms within dioritic–granitic orthogneisses and Al-rich paragneisses. An integrated study involving laser Raman and scanning electron microscope analyses of mineral inclusions from zircons, cathodoluminescence imaging, and LA–ICP–MS U–Pb dating of zircons, shows that magmatic zircons in these meta-mafic rocks record four age groups of 2500–2450, 2300–2100, 1970–1930, and ca. 1850Ma, indicating multiple mafic magmatic events occurred within the Daqingshan–Wulashan Complex. In addition, four groups of metamorphic zircons with ages of ca. 2450, ca. 1950, ca. 1900, and ca. 1850Ma are present within these meta-mafic rocks. Zircons of the first (oldest) group contain medium- to low-pressure (MLP) granulite facies mineral inclusions of orthopyroxene+clinopyoxene+amphibole+plagioclase+quartz, and yield ages of ca. 2450Ma, representing the timing of the early MLP granulite facies metamorphic event within the Daqingshan–Wulashan reworked basement complex. In contrast, zircons of the second group are free of mineral inclusions, and yield ages of ca. 1950Ma, which is considered to be the timing of the regional high-grade metamorphic and structural event probably caused by the collision of the Yinshan and Ordos Blocks. Zircons of the third group contain MLP granulite facies mineral inclusions of orthopyroxene+clinopyoxene+amphibole+plagioclase+quartz, similar to the zircons of the first group, but yield younger ages of ca. 1900Ma, interpreted as the timing of the regional MLP granulite facies metamorphism that most likely occurred during the early stage of post-orogenic exhumation of the Daqingshan–Wulashan Complex. Zircons of the fourth group contain MLP amphibolite facies mineral inclusions of clinopyoxene+amphibole+plagioclase+quartz, and yield the youngest ages of ca. 1850Ma, which probably represent the timing of the regional amphibolite facies metamorphism during the late stage of post-orogenic exhumation of the Daqingshan–Wulashan Complex. Combined with previous geological data of the Khondalite Belt, it is speculated that the multiple mafic magmatism and contemporaneous high-grade metamorphism of the Daqingshan–Wulashan Complex from the Khondalite Belt were most likely generated by an orogenic process involving early subduction–collision and late exhumation in an active continental margin arc.
Field effect relies on the nonlinear current–voltage relation in semiconductors; analogously, materials that respond nonlinearly to an optical field can be utilized for optical modulation. For ...instance, nonlinear optical (NLO) materials bearing a saturable absorption (SA) feature an on–off switching behavior at the critical pumping power, thus enabling ultrafast laser pulse generation with high peak power. SA has been observed in diverse materials preferably in its nanoscale form, including both gaped semiconductor nanostructures and gapless materials like graphene; while the presence of optical bandgap and small carrier density have limited the active spectral range and intensity. We show here that solution-processed plasmonic semiconductor nanocrystals exhibit superbroadband (over 400 THz) SA, meanwhile with large modulation depth (∼7 dB) and ultrafast recovery (∼315 fs). Optical modulators fabricated using these plasmonic nanocrystals enable mode-locking and Q-switching operation across the near-infrared and mid-infrared spectral region, as exemplified here by the pulsed lasers realized at 1.0, 1.5, and 2.8 μm bands with minimal pulse duration down to a few hundreds of femtoseconds. The facile accessibility and superbroadband optical nonlinearity offered by these nonconventional plasmonic nanocrystals may stimulate a growing interest in the exploiting of relevant NLO and photonic applications.
Quality prediction, as the basis of quality control, is dedicated to predicting quality indices of the manufacturing process. In recent years, data-driven deep learning methods have received a lot of ...attention due to their accuracy, robustness, and convenience for the prediction of quality indices. However, the existing studies mainly focus on the quality prediction of a single machine, while ignoring dependency relationships among multiple machines in multistage manufacturing process. To tackle the above issues, a novel path enhanced bidirectional graph attention network (PGAT) is proposed in this article. PGAT models the dependencies among machines into directed graphs and introduces graph attention network to encode the dependencies. Nonetheless, it is difficult for graph neural networks to encode long-distance dependencies. Hence, dependency path information is introduced into the features of machines. Moreover, in order to solve the label noise problem that often occurs in actual industrial dataset, a masked loss function is devised. With its help, batch training with noisy labels can be achieved, which improves the training efficiency. Furthermore, experiments are conducted on a public quality prediction dataset collected from an actual production line. PGAT achieves the state-of-the-art results on this dataset, which confirms the effectiveness of PGAT. Additionally, the experimental results demonstrate the critical role of modeling dependency relationships among machines.
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