The Relationship Between Negotiable Fate and Life Satisfaction: The Serial Mediation by Self-Esteem and Positive Psychological Capital.

Purpose: Negotiable fate as a belief in coping with the difficulties and uncertainties of life has an impact on people's mental health. This study aims to understand the influence of negotiate fate on college students' life satisfaction and its underlying mechanism. Methods: A cross-sectional study was conducted with the participation of 1523 students from six universities across China. The study aimed to measure the variables of negotiable fate, self-esteem, positive psychological capital, and life satisfaction of all participants. To investigate the effect of negotiable fate on college students' life satisfaction and the mediating roles of self-esteem and positive psychological capital in this relationship, a serial mediation effects model using Hayes' PROCESS was employed. Results: The results suggest that negotiable fate has a positive predictive effect on college students' life satisfaction. The impact of negotiable fate on college students' life satisfaction was mediated by self-esteem and positive psychological capital, and the chained mediation of self-esteem and positive psychological capital. Conclusion: To summarize, the belief of negotiable fate has practical significance for the enhancement of college student's mental health and quality of life, and the cultivation of college students' belief of negotiable fate can be actively promoted in the future to help them better cope with the uncertainties and challenges in their lives to improve their life satisfaction.

Synthesis of C-Oligosaccharides via Ni-Catalyzed Reductive Hydroglycosylation.

C-Oligosaccharides are metabolically stable surrogates of native glycans containing O/N/S-glycosidic linkages and thus have therapeutic potential. Here we report a straightforward approach to the synthesis of vinyl C-linked oligosaccharides via the Ni-catalyzed reductive hydroglycosylation of alkynyl glycosides with glycosyl bromides.

Convergent Synthesis of the Nonreducing Hexasaccharide Fragment and the Dodecasaccharide Scaffold of Marine Lipopolysaccharide Axinelloside A.

A convergent synthesis of the dodecasaccharide scaffold of axinelloside A was achieved through Au(I)-catalyzed [6+6] glycosylation. The initially devised [3+1+2] assembly of the nonreducing hexasaccharide fragment was low-yielding, whereas a convergent [3+3] glycosylation under Au(I) catalysis was proven feasible, allowing for a semi-gram scale preparation of the wanted hexasaccharide. The requisite 1,2-cis glycosidic bonds were forged in a highly stereoselective fashion by virtue of remote acetyl group participation, and judicious manipulation of protecting groups. The synthetic dodecasaccharide has been properly protected for the downstream elaboration toward its natural form.

Synthesis of the Reducing-end Hexasaccharide Fragment of Marine Lipopolysaccharide Axinelloside A.

Chemical synthesis of an orthogonally protected hexasaccharide relevant to the reducing-end half of axinelloside A, a highly sulfated marine lipopolysaccharide, is disclosed. The synthesis features preparation of the scyllo-inositol unit via a Ferrier-type-II rearrangement, construction of the 1,2-cis-glycosidic bonds via remote participation, and concise [2+2+2] assembly via Au(I)-catalyzed glycosylation.

Synthesis of 2-Indolyl C-Glycoside Neopetrosins A and C and Congeners via Ni-Catalyzed Photoreductive Cross-Coupling.

The synthesis of neopetrosins A and C, two 2-indolyl C-α-d-mannopyranosides, and their congeners has been realized via a direct Ni/photoredox-catalyzed reductive coupling of 3-methoxycarbonyl-2-iodo-1H-indoles with pyranosyl bromides.

Stereoselective Synthesis of ß-glycosyl Esters via 1-Hydroxybenzotriazole Mediated Acylation of Glycosyl Hemiacetals.

Highly stereoselective access to ß-glycosyl esters was disclosed, employing 1-hydroxybenzotriazole (HOBt) mediated esterification of glycosyl hemiacetals in the presence of EDCI and 1,4-diazabicyclo[2.2.2]octane (DABCO). Mechanistic studies indicated a dynamic kinetic acylation pathway. In addition, a stereoretentive esterification of glycosyl hemiacetals with tert-butyloxycarbonyl ortho-hexynylbenzoate and DMAP was also reported.

A Cu(OTf)2-Catalyzed Glycosylation with Glycosyl ortho-N-Phthalimidoylpropynyl Benzoates as Donors.

A Cu(OTf)2-catalyzed glycosylation protocol using glycosyl ortho-N-phthalimidoylpropynyl benzoates (NPPBs) as donors was disclosed, which features an inexpensive copper catalyst, operationally convenient conditions, high to excellent yields, and a broad substrate scope. Mechanistic studies indicated an isochromen-4-yl copper(II) intermediate arising from the departure of the leaving group.

Dzyaloshinskii-Moriya-Interaction-Like Behavior in Confined Permalloy Nanostructures via Coupled Magnetic Vortices.

Dzyaloshinskii-Moriya interaction (DMI), one of antisymmetric exchanges, originates from the combination of low structural symmetry and large spin-orbit coupling and favors magnetization rotations with fixed chirality. Herein, this work reports a DMI-like behavior in permalloy via coupled vortices in confined structures. Under the in-plane magnetic fields, continuous reversals of different coupled vortices are directly observed by in situ Lorentz transmission electron microscopy, and reproduced by complementary micromagnetic simulations. The statistical results show that coupled vortices with opposite chirality appear more frequently with the frequency up to about 60%. Such an asymmetric phenomenon mainly arises from a DMI-like behavior, associated with the increased total energy difference between different ground-state coupled vortices. Moreover, in the reversal process, the junction between disks accelerates the annihilation of vortices moving toward it and is also the starting point of vortex nucleation. These results provide an effective method to generate a DMI-like behavior in magnetic systems with symmetry breaking surface and benefit the future development of vortex-based spintronic devices.

Significant Role of Interfacial Spin-Orbit Coupling in the Spin-to-Charge Conversion in Pt/NiFe Heterostructure.

For the spin-to-charge conversion (SCC) in heavy metal/ferromagnet (HM/FM) heterostructure, the contribution of interfacial spin-orbit coupling (SOC) remains controversial. Here, we investigate the SCC process of the Pt/NiFe heterostructure by the spin pumping in YIG/Pt/NiFe/IrMn multilayers. Due to the exchange bias of NiFe/IrMn structure, the NiFe magnetization can be switched between magnetically unsaturated and saturated states by opposite resonance fields of YIG layer. The spin-pumping signal is found to decrease significantly when the NiFe magnetization is changed from the saturated state to the unsaturated state. Theoretical analysis indicates that the interfacial spin absorption is enhanced for the above-mentioned NiFe magnetic state change, which results in the increased and decreased spin flow in the Pt layer and across the Pt/NiFe interface, respectively. These results demonstrate that in our case the interfacial SOC effect at the Pt/NiFe interface is dominant over the bulk inverse spin Hall effect in the Pt layer. Our work reveals a significant role of interfacial SOC in the SCC in HM/FM heterostructure, which can promote the development of high-efficiency spintronic devices through interfacial engineering.

Characterizing the Gut Microbiota of Eurasian Otter (Lutra lutra chinensis) and Snub-Nosed Monkey (Rhinopithecus roxellana) to Enhance Conservation Practices in the Foping National Nature Reserve of China.

Understanding the interaction between the microbial composition in the habitat and the gut of wildlife will contribute to conservation efforts since changes in the gut microbiome have been proven to influence the healthy and nutritional status of the host. This study analyzed the relationship between soil microbes and the microbial diversity and structure of the distal gut of the terrestrial golden snub-nosed monkey and Eurasian otter in the Foping National Nature Reserve (FNNR). A total of 15 otter fecal samples and 18 monkey fecal samples were collected from which 5 and 6 samples, respectively, were randomly selected for microbiome analysis. The remaining samples were used for fecal short-chain fatty acids (SCFAs) analysis. Soil samples from the otter and monkey habitats at each sampling point (eight in total) were also collected for microbiome analysis. The microbial phyla with the greatest relative abundance in soil or animal samples were Proteobacteria (41.2, 32.7, and 73.3% for soil, otters, and monkeys, respectively), Firmicutes (0.4% soil, 30.1% otters, and 14.4% monkeys), Bacteroidota (5.6% soil, 17.0% otters, and 8.3% monkeys), and Acidobacteriota (24.6% soil, 1.7% otters, and 0.1% monkeys). The estimation of alpha diversity indices revealed that the feature, Chao1, and Shannon indices of the soil microbiome were the greatest (p < 0.01) among the three groups, followed by those of the otter microbiome and those of the monkey microbiome (p < 0.01). Beta diversity analyses confirmed differences in the microbiota of the three types of samples. The determination of SCFA concentration in feces revealed that total volatile fatty acids, acetic acid, and isovaleric acid were greater (p < 0.05) in otters than in monkeys, while propionic acid followed the opposite pattern (p < 0.05). Correlation analysis of the microbiome and SCFA contents showed that propionic acid was positively correlated with significantly different bacterial groups, while acetic and butyric acid and total volatile acids were negatively correlated. This study confirmed that the fecal microbes of Eurasian otters and golden snub-nosed monkeys in the reserve are related to the soil microbial communities of their habitats, but they have different bacterial community structures and compositions, and there are different SCFA metabolic patterns in the gut of the two animals. The present study will help to improve wildlife protection in the FNNR.

Sign Change of Spin-Orbit Torque in Pt/NiO/CoFeB Structures.

Antiferromagnetic insulators have recently been proved to support spin current efficiently. Here, we report the dampinglike spin-orbit torque (SOT) in Pt/NiO/CoFeB has a strong temperature dependence and reverses the sign below certain temperatures, which is different from the slight variation with temperature in the Pt/CoFeB bilayer. The negative dampinglike SOT at low temperatures is proposed to be mediated by the magnetic interactions that tie with the "exchange bias" in Pt/NiO/CoFeB, in contrast to the thermal-magnon-mediated scenario at high temperatures. Our results highlight the promise to control the SOT through tuning the magnetic structure in multilayers.

Reversal of the Pinning Direction in the Synthetic Spin Valve with a NiFeCr Seed Layer.

The effect of the seed layers on the magnetic properties of the giant magnetoresistance thin films has received a lot of attention. Here, a synthetic spin valve film stack with a wedge-shaped NiFeCr seed layer is deposited and annealed following a zero-field cooling procedure. The film crystallinity and magnetic properties are studied as a function of the NiFeCr seed layer thickness. It is found that the exchange coupling field from the IrMn/CoFe interface and the antiferromagnetic coupling field in the synthetic antiferromagnet both increase as the seed layer thickness increases, indicating the perfection of film texture. In this film, the critical thickness of the NiFeCr seed layer for the formation of the ordered IrMn3 texture is about 9.3 nm. Meanwhile, a reversal of the pinning direction in the film is observed at this critical thickness of NiFeCr. This phenomenon can be explained in a free energy model by the competition effect between the exchange coupling and the interlayer coupling during the annealing process.

Total Synthesis of Starfish Cyclic Steroid Glycosides.

Starfishes have evolved with a special type of secondary metabolites, namely starfish saponins, to ward off various predators and parasites; among them, the starfish cyclic steroid glycosides stand out structurally, featuring a unique 16-membered ring formed by bridging the steroidal C3 and C6 with a trisaccharide. The rigid cyclic scaffold and the congested and vulnerable steroid-sugar etherate linkage present an unprecedented synthetic challenge. Here we report a collective total synthesis of the major starfish cyclic steroid glycosides, namely luzonicosides A (1) and D (2) and sepositoside A (3), with an innovative approach, which entails a de novo construction of the ether-linked hexopyranosyl units, use of olefinic pyranoses as sugar precursors, and a decisive ring-closing glycosylation under the mild gold(I)-catalyzed conditions.

Nonreciprocal Transport in a Bilayer of MnBi2Te4 and Pt.

MnBi2Te4 (MBT) is the first intrinsic magnetic topological insulator with the interaction of spin-momentum locked surface electrons and intrinsic magnetism, and it exhibits novel magnetic and topological phenomena. Recent studies suggested that the interaction of electrons and magnetism can be affected by the Mn-doped Bi2Te3 phase at the surface due to inevitable structural defects. Here, we report an observation of nonreciprocal transport, that is, current-direction-dependent resistance, in a bilayer composed of antiferromagnetic MBT and nonmagnetic Pt. The emergence of the nonreciprocal response below the Néel temperature confirms a correlation between nonreciprocity and intrinsic magnetism in the surface state of MBT. The angular dependence of the nonreciprocal transport indicates that nonreciprocal response originates from the asymmetry scattering of electrons at the surface of MBT mediated by magnon. Our work provides an insight into nonreciprocity arising from the correlation between magnetism and Dirac surface electrons in intrinsic magnetic topological insulators.

A Stereoselective Glycosylation Approach to the Construction of 1,2-trans-ß-d-Glycosidic Linkages and Convergent Synthesis of Saponins.

Conventional syntheses of 1,2-trans-ß-d- or α-l-glycosidic linkages rely mainly on neighboring group participation in the glycosylation reactions. The requirement for a neighboring participation group (NPG) excludes direct glycosylation with (1→2)-linked glycan donors, thus only allowing stepwise assembly of glycans and glycoconjugates containing this type of common motif. Here, a robust glycosylation protocol for the synthesis of 1,2-trans-ß-d- or α-l-glycosidic linkages without resorting to NPG is disclosed; it employs an optimal combination of glycosyl N-phenyltrifluroacetimidates as donors, FeCl3 as promoter, and CH2 Cl2 /nitrile as solvent. A broad substrate scope has been demonstrated by glycosylations with 12 (1→2)-linked di- and trisaccharide donors and 13 alcoholic acceptors including eight complex triterpene derivatives. Most of the glycosylation reactions are high yielding and exclusively 1,2-trans selective. Ten representative, naturally occurring triterpene saponins were thus synthesized in a convergent manner after deprotection of the coupled glycosides. Intensive mechanistic studies indicated that this glycosylation proceeds by SN 2-type substitution of the glycosyl α-nitrilium intermediates. Importantly, FeCl3 dissociates and coordinates with nitrile into [Fe(RCN)n Cl2 ]+ and [FeCl4 ]- , and the ferric cationic species coordinates with the alcoholic acceptor to provide a protic species that activates the imidate, meanwhile the poor nucleophilicity of [FeCl4 ]- ensures an uninterruptive role for the glycosidation.

Activation of PI3K/AKT Pathway Is a Potential Mechanism of Treatment Resistance in Small Cell Lung Cancer.

PURPOSE: Here, we have investigated treatment resistance mechanisms in small cell lung cancer (SCLC) by focusing on comparing the genotype and phenotype in tumor samples of treatment-resistant and treatment-sensitive SCLC. EXPERIMENTAL DESIGN: We conducted whole-exome sequencing on paired tumor samples at diagnosis and relapse from 11 patients with limited-stage (LS)-SCLC and targeted sequencing of 1,021 cancer-related genes on cell-free DNA at baseline and paired relapsed samples from 9 additional patients with LS-SCLC. Furthermore, we performed label-free mass spectrometry-based proteomics on tumor samples from 28 chemo-resistant and 23 chemo-sensitive patients with extensive-stage (ES)-SCLC. The main findings were validated in vitro in chemo-sensitive versus chemo-resistant SCLC cell lines and analyses of transcriptomic data of SCLC cell lines from a public database. RESULTS: Genomic analyses demonstrated that at relapse of LS-SCLC, genes in the PI3K/AKT signaling pathway were enriched for acquired somatic mutations or high-frequency acquired copy-number variants. Pathway analysis on differentially upregulated proteins from ES-SCLC cohort revealed enrichment in the HIF-1 signaling pathway. Importantly, 7 of 62 PI3K/AKT pathway genes containing acquired somatic copy-number amplifications were enriched in HIF-1 pathway. Analyses of transcriptomic data of SCLC cell lines from public databases confirmed upregulation of PI3K/AKT and HIF-1 pathways in chemo-resistant SCLC cell lines. Furthermore, chemotherapy-resistant cell lines could be sensitive to PI3K inhibitors in vitro. CONCLUSIONS: PI3K/AKT pathway activation may be one potential mechanism underlying therapeutic resistance of SCLC. This finding warrants further investigation and provides a possible approach to reverse resistance to chemo/radiotherapy.

Comparison of Remimazolam-Flumazenil versus Propofol for Rigid Bronchoscopy: A Prospective Randomized Controlled Trial.

Background: Remimazolam is a novel ultrashort-acting intravenous benzodiazepine sedative−hypnotic that significantly reduces the times to sedation onset and recovery. This trial was conducted to confirm the recovery time from anesthesia of remimazolam-flumazenil versus propofol in patients undergoing endotracheal surgery under rigid bronchoscopy. Methods: Patients undergoing endotracheal tumor resection or stent implantation were randomly allocated into a remimazolam group (Group R) or a propofol group (Group P). The primary outcome was the recovery time from general anesthesia. The secondary outcomes were the time to loss of consciousness (LoC), hemodynamic fluctuations, and adverse events. Results: A total of 34 patients were screened, and 30 patients were enrolled in the study. The recovery time was significantly shorter for Group R (140 ± 52 s) than for Group P (374 ± 195 s) (p < 0.001). The times to LoC were 76 ± 40 s in Group R and 75 ± 25 s in Group P and were not significantly different. There were also no significant differences in hemodynamic fluctuations or adverse events between the two groups. Conclusions: The recovery time from general anesthesia in rigid bronchoscopy patients was shorter using remimazolam-flumazenil than with propofol, with no dramatic hemodynamic fluctuations and adverse events or differences between the agents. Remimazolam-flumazenil allows for faster recovery from anesthesia than propofol.

Antiferromagnetic spintronics: An overview and outlook.

Over the past few decades, the diversified development of antiferromagnetic spintronics has made antiferromagnets (AFMs) interesting and very useful. After tough challenges, the applications of AFMs in electronic devices have transitioned from focusing on the interface coupling features to achieving the manipulation and detection of AFMs. As AFMs are internally magnetic, taking full use of AFMs for information storage has been the main target of research. In this paper, we provide a comprehensive description of AFM spintronics applications from the interface coupling, read-out operations, and writing manipulations perspective. We examine the early use of AFMs in magnetic recordings and conventional magnetoresistive random-access memory (MRAM), and review the latest mechanisms of the manipulation and detection of AFMs. Finally, based on exchange bias (EB) manipulation, a high-performance EB-MRAM is introduced as the next generation of AFM-based memories, which provides an effective method for read-out and writing of AFMs and opens a new era for AFM spintronics.

Facile access to C-glycosyl amino acids and peptides via Ni-catalyzed reductive hydroglycosylation of alkynes.

C-Glycosyl peptides/proteins are metabolically stable mimics of the native glycopeptides/proteins bearing O/N-glycosidic linkages, and are thus of great therapeutical potential. Herein, we disclose a protocol for the syntheses of vinyl C-glycosyl amino acids and peptides, employing a nickel-catalyzed reductive hydroglycosylation reaction of alkyne derivatives of amino acids and peptides with common glycosyl bromides. It accommodates a wide scope of the coupling partners, including complex oligosaccharide and peptide substrates. The resultant vinyl C-glycosyl amino acids and peptides, which bear common O/N-protecting groups, are amenable to further transformations, including elongation of the peptide and saccharide chains.

Quantum frequency doubling in the topological insulator Bi2Se3.

The nonlinear Hall effect due to Berry curvature dipole (BCD) induces frequency doubling, which was recently observed in time-reversal-invariant materials. Here we report novel electric frequency doubling in the absence of BCD on a surface of the topological insulator Bi2Se3 under zero magnetic field. We observe that the frequency-doubling voltage transverse to the applied ac current shows a threefold rotational symmetry, whereas it forbids BCD. One of the mechanisms compatible with the symmetry is skew scattering, arising from the inherent chirality of the topological surface state. We introduce the Berry curvature triple, a high-order moment of the Berry curvature, to explain skew scattering under the threefold rotational symmetry. Our work paves the way to obtain a giant second-order nonlinear electric effect in high mobility quantum materials, as the skew scattering surpasses other mechanisms in the clean limit.