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The critical current of a multi-stage high-temperature superconducting (HTS) twisted cable using cable-in-conduit conductor (CICC) is vital for its performance, since it determines the maximum current that the superconductor can carry in a superconducting state. This cable has a composite conductor structure with high current-carrying capacity, cooling efficiency, and stability, and can be used in high-field magnets. In this paper, based on a structure of a first-stage cable with HTS stacked-squared wires, a three-dimensional (3D) finite element model is established by the homogenization method to make analytical calculations of the current density distribution and critical current values of the multi-stage twisted cable. The simulation results show that the critical current at 77 K of the multi-stage high-temperature superconducting twisted cable is 5.9 kA. Besides, the skin effect causes a higher current density near the outer side in comparison to the inner side. This work could be as a reference for designing a high field magnet using HTS square wires, and substantially reduces the computational complexity of simulating cables with complex structure.

The complexity of the Cable-in-Conduit Conductor (CICC) structure made with second-generation high-temperature superconducting materials presents challenges for quench detection, which is different from low-temperature superconductors due to their relatively low propagation velocity. This study builds upon simulation results from a quench detection method that focuses on current redistribution effects. The objective is to further investigate the relationship between the level of current redistribution, hot spot power, operating current, and the size of the detection signal. Parameters under examination include the height of the Hall probe, the distance between the Hall probe and the hot spot, and the square wire identification where the Hall probe is positioned. The findings of this study demonstrate that the quench detection method, based on current redistribution effects, is effective in detecting hot spots in twisted HTS cables. Furthermore, a comprehensive analysis is conducted to evaluate the impact of the operating current on the level of current redistribution and the influence of the Hall probe height on the detection signal.

• A novel high entropy perovskite oxygen reduction reaction electrocatalyst, La(Cr 0.2 Mn 0.2 Fe 0.2 Co 0.2 Ni 0.2)O 3 , was prepared by the efficient spray pyrolysis method. • The balance between moderate e g occupancy and high TM-O bond covalency was achieved by b site entropy driven strategy, which resulted in a remarkable enhancement in both ORR activity and durability of perovskite Lanthanide-transition metal oxides LaTMO 3. • Based on crystal field theory and P-V-L valence bond theory, e g occupancy, TM-O bond covalence and TM-O bond energy were determined quantitatively, which were regarded as the descriptors of ORR activity and durability. Forming high entropy oxide provides a feasible approach to finding a balance among moderate e g occupancy, high transition metal-oxygen (TM-O) covalency, and lattice energy, which is essential to ensure efficient and durable oxygen reduction reaction (ORR) process for perovskite lanthanide-transition metal oxides (LaTMO 3). However, due to the compositional complexity, clarifying the relevance among the high entropy components, e g occupancy, TM-O properties, and ORR performance still remains a challenge. Herein, adopting the B site entropy-driven strategy, a series of LaTMO 3 (TM = Cr, Mn, Fe, Co, Ni) with tunable e g occupancy and TM-O bond properties are synthesized, and the correlations between high entropy elements, e g occupancy, TM-O properties, and ORR performances are revealed quantitively based on the crystal field theory and the Phillips–Van Vechten–Levine (P–V–L) valence bond theory. High entropy La(Cr 0.2 Mn 0.2 Fe 0.2 Co 0.2 Ni 0.2)O 3 delivers a low overpotential of 493 mV (vs. 503 mV for LaMnO 3) and a minuscule decline by only 1.7% (vs. 4.4% for LaMnO 3) in half wave potential after 10,000 cycles, which can be associated with the tailored e g occupancy (1.06) and the significant enhancement in both TM-O covalency (4%) and lattice energy (691.75 kJ mol–1). This work not only demonstrates the prospects of high entropy LaTMO 3 in the ORR field but also provides a new perspective for the quantitative analysis of the structure-activity relationship for high entropy oxide ORR catalysts. [Display omitted] [ABSTRACT FROM AUTHOR]

The application of innovative adsorbents with high adsorption capacity and easy recovery in wastewater treatment has always been of great concern. This study employed κ-carrageenan to enhance the dispersion of magnetic nanoparticles and improve their stability through Ca2+and Na+crosslinkinelg. XRD, FTIR, SEM and EDS revealed that the magnetic nanoparticles were coated with κ-carrageenan. The synthesized MΚC@Fe3O4MNPs exhibited a stable structure and multiple adsorption sites, which was beneficial for the treatment of cationic dyes in wastewater. The absorption results indicated that abundant active sites on the surface of the adsorbent efficiently adsorbed the three cationic dyes. Through optimization experiments, the MΚC@Fe3O4MNPs demonstrated maximum adsorption capacities of 729.9 mg/g, 184.1 mg/g, and 311.0 mg/g for methylene blue, malachite green, and safranin T, respectively. The adsorbent could maintain excellent adsorption efficiency even after 5 cycles of use. The adsorption mechanisms for the three cationic dyes included electrostatic interactions, n-π interactions, and hydrogen bonding. Therefore, the MΚC@Fe3O4MNPs showed highly efficient adsorption and separation of cationic dyes and are suitable candidates for dye wastewater treatment.

The Ross-Amundsen sector is experiencing an accelerating warming trend and a more intensive advective influx of marine air streams. As a result, massive surface melting events of the ice shelf are occurring more frequently, which puts the West Antarctica Ice Sheet at greater risk of degradation. This study shows the connection between surface melting and the prominent intrusion of warm and humid air flows from lower latitudes. By applying the Climate Feedback-Response Analysis Method (CFRAM), the temporal surge of the downward longwave (LW) fluxes over the surface of the Ross Ice Shelf (RIS) and adjacent regions are identified for four historically massive RIS surface melting events. The melting events are decomposed to identify which physical mechanisms are the main contributors. We found that intrusions of warm and humid airflow from lower latitudes are conducive to warm air temperature and water vapor anomalies, as well as cloud development. These changes exert a combined impact on the abnormal enhancement of the downward LW surface radiative fluxes, significantly contributing to surface warming and the resultant massive melting of ice.

Despite the surging research in the literature on major natural hazards globally, most research to date has been cross-sectional in nature. Also, few studies have addressed human strengths. In response to the call for longitudinal studies, this secondary analysis of a two-wave survey examined the effects of character strengths and coping on Hurricanes Katrina and Rita (H-KR) volunteers, alongside hazard-related factors and peritraumatic emotional responses. Wave-1 and Wave-2 surveys were conducted at three-months and six-months at five public universities in the Gulf Coast affected by the disaster. A total of 542 participants completed Wave-1 and 201 completed Wave 2 questionnaires, because only two universities were able to conduct the follow-up. Multivariate analyses revealed that the finding was partly consistent with a cross-sectional study on Hurricanes Maria and Michael (H-MM); both events are the deadliest storms in the United States (U.S.). This prospective study supported the last damage of peritraumatic negative emotions and hurricane stressors on traumatization. However, the desirable effect of trait optimism was not evident overtime, perhaps partly due to the significantly smaller number in Wave-2 survey. Also, the link between negative coping and trauma symptom was not replicated. Still, the finding may imply that early intervention for emotional responses will be important in future disaster relief.

Alzheimer’s disease (AD) is the leading cause of dementia in older individuals and is an escalating challenge to global public health. Pharmacy therapy of AD is one of the well-funded areas; however, little progress has been made due to the complex pathogenesis. Recent evidence has demonstrated that modifying risk factors and lifestyle may prevent or delay the incidence of AD by 40%, which suggests that the management should pivot from single pharmacotherapy toward a multipronged approach because AD is a complex and multifaceted disease. Recently, the gut-microbiota-brain axis has gained tremendous traction in the pathogenesis of AD through bidirectional communication with multiple neural, immune, and metabolic pathways, providing new insights into novel therapeutic strategies. Dietary nutrition is an important and profound environmental factor that influences the composition and function of the microbiota. The Nutrition for Dementia Prevention Working Group recently found that dietary nutrition can affect cognition in AD-related dementia directly or indirectly through complex interactions of behavioral, genetic, systemic, and brain factors. Thus, considering the multiple etiologies of AD, nutrition represents a multidimensional factor that has a profound effect on AD onset and development. However, mechanistically, the effect of nutrition on AD is uncertain; therefore, optimal strategies or the timing of nutritional intervention to prevent or treat AD has not been established.Thus, this review summarizes the current state of knowledge concerning nutritional disorders, AD patient and caregiver burden, and the roles of nutrition in the pathophysiology of AD. We aim to emphasize knowledge gaps to provide direction for future research and to establish optimal nutrition-based intervention strategies for AD.

The effect of Tremella fuciformispolysaccharide (TFP) on the retrogradation property and aroma profile changes of tteok during storage was investigated. Results indicated that addition of TFP significantly increased the stability to thermal and mechanical shearing of starch, decreased short-term retrogradation, the hardness and the retrogradation enthalpy (ΔH) of tteok during storage, but had no significant effect on the amylopectin chain length of tteok. The possible mechanism for the retarding staling effect of TFP is related to the interaction between TFP and starch chains that interferes with the alignment of starch chains. Electronic nose and gas chromatography-mass spectrum (GC-MS) analysis results showed that the difference in the concentrations of volatile compounds and fatty acids of tteoks at different storage time gradually increased with the advancement of storage period. The addition of TFP to tteok inhibited the development of unpleasant volatile compounds, probably by delaying the oxidation and decomposition of lipids and preserving the antioxidant phenolic compounds in tteok, thus slowing down the flavor deterioration of tteok and contributing to flavor maintainace. Overall, this study could help food manufacturers to choose a high-effective and natural polysaccharide to control the retrogradation rate and flavor loss of tteok.

Herein we report an electrochemical strategy for the construction of polysubstituted oxazoles from easily available ketones and acetonitrile under room temperature. The method shows high efficiency, a broad substrate scope, and requires no external chemical oxidant. Mechanistic investigations suggest that the reaction proceeds through a Ritter-type reaction/oxidative cyclization using acetonitrile as the reactant and solvent. X-ray crystallographic analysis reveals that the reaction involves the attack of acetonitrile on the carbonyl carbon instead of the α-carbon.

ABSTRACTThe in-situ measurements for r-tables have attracted special attention owing to their advantages, including increased speed, simplicity of use, and nondestructive road effects. This study presents a database retrieval method proposed for the construction of a full-scale r-table from an r-table database with 25 rcoefficients used as input parameters. The proposed method was used in an in-situ, r-table measurement device as a data processing algorithm. To evaluate the accuracy of the proposed method, we performed a) a table-to-table comparison of Q0, S1, and r-tables constructed by different methods and b) comparisons of calculated luminance values (Lave, U0, Ul) for a typical road-lighting scenario based on the use of different r-tables. The table-to-table comparison results indicate that following the application of the proposed method, its calculated Q0, S1, and r-table values were very close to their actual values (EQ0 = 2.1%, ES1 = 5.0%, Error = 2.3%). Moreover, the proposed method also exhibits an improved luminance response and achieves a 2.1% difference in Lave, a 3% difference in U0, and a 1.8% difference in Ul. This study proves that the proposed database retrieval method improves the model prediction accuracy.

The growing epidemic of diabetes means that there is a need for therapies that are more efficacious, safe, and convenient. Here, we report the efficient synthesis of a novel disulfide dimer of human insulin tethered at the N-terminus of its B-chain through placement of a cysteine residue. The resulting peptide was shown to bind to both the insulin receptor isoform B and insulin-like growth factor-1 receptor with comparable affinity to native insulin. In in vivoinsulin tolerance tests, the dimer was equipotent to Actrapid insulin and possessed a sustained duration of action greater than that of Actrapid and Glargine. While the secondary structure of our dimeric insulin was similar to that of insulin, it was more resistant to proteolysis. More importantly, our analogue was produced in quantitative yield from a monomeric thiol insulin scaffold. Our results suggest that this dimer has significant potential to address the clinical needs in the treatment of diabetes.

The current commercially available glucagon formulations for the treatment of severe hypoglycemia must be reconstituted immediately prior to use, owing to the susceptibility of glucagon to fibrillation and aggregation in an aqueous solution. This results in the inconvenience of handling, misuse, and wastage of this drug. To address these issues, we synthesized a glycosylated glucagon analogue in which the 25th residue (Trp) was replaced with a cysteine (Cys) and a Br-disialyloligosaccharide was conjugated at the Cys thiol moiety. The resulting analogue, glycoglucagon, is a highly potent full agonist at the glucagon receptor. Importantly, glycoglucagon exhibits markedly reduced propensity for fibrillation and enhanced thermal and metabolic stability. This novel analogue is thus a valuable lead for producing stable liquid glucagon formulations that will improve patient compliance and minimize wastage.

The applications of bioconjugation chemistry are rapidly expanding, and the addition of new strategies to the bioconjugation and ligation toolbox will further advance progress in this field. Herein, we present a detailed study of the Diels–Alder cycloaddition (DAC) reaction between pentafulvenes and maleimides in aqueous solutions and investigate the reaction as an emerging bioconjugation strategy. The DAC reactions were found to proceed efficiently, quantitatively yielding cycloadducts with reaction rates ranging up to ∼0.7 M–1s–1for a series of maleimides, including maleimide-derivatized peptides and proteins. The absence of cross-reactivity of the pentafulvene with a large panel of functional (bio)molecules and biological media further demonstrated the bioorthogonality of this approach. The utility of the DAC reaction for bioorthogonal bioconjugation applications was further demonstrated in the presence of biological media and proteins, as well as through protein derivatization and labeling, which was comparable to the widely employed sulfhydryl–maleimide coupling chemistry.

Freeform illumination design for extended sources is a very challenging but rewarding issue that can benefit a wide range of illumination systems. Here, we propose a method that can achieve compact and highly efficient illumination lenses by deconvolving the blur caused by the extent from light sources. We combine the illumination calculation with the mathematical model of spatially variant convolution and develop a direct computational scheme to calculate the blur kernel without approximations. Two design examples with high optical performances are presented to demonstrate the effectiveness of the proposed method.

Term energies, oscillator strengths, transition probabilities, and transition wavelengths among the low-lying states of (1s2)2s22p2, 2s22p3p, 2s2p3, 2s22p3s, and 2s22p3d 1,3,5L L= S, P, D, F in N+, F3+, and Ne4+ions were calculated by using the multiconfiguration Rayleigh-Ritz variation method and restricted variation method. The transition oscillator strengths and transition probabilities for the electric dipole transitions are both given in length and velocity gauges. Deviations between these two gauge values are discussed. The calculated atomic parameters are in good agreement with the observed experimental results and other theoretical data. Furthermore, the uncertainty of each electric dipole transition is estimated. Several uncertainties of transition parameters are improved when comparing with values from national institute of standards and technology NIST database. Atomic parameters presented in this paper should be useful for identifying the levels as well as for precise spectral modeling in astrophysical and laboratory plasmas in the future work.

Multiblock copolymer brushes have broad application in thermoplastic elastomers, drug delivery, porous materials, and nanolithography due to their unique structure and properties. In this research, a novel multiblock copolymer brush (PHEA‐g‐PEG)x‐co‐ (PEG23)ywas synthesized by combining the efficient double strain‐promoted azide‐alkyne cycloaddition (DSPAAC) and copper‐catalyzed azide‐alkyne cycloaddition (CuAAC) click reactions. The gel permeation chromatography (GPC), proton nuclear magnetic resonance spectrometer (1H NMR), Fourier transform infrared spectroscopy (FT‐IR), and atomic force microscopy (AFM) were used to characterize the prepared polymers. The results demonstrated that the novel multiblock copolymer brush was successfully prepared. The mole ratio was 1/0.84 between block PHEA‐g‐PEG and block PEG23, and the grafting density was 100%. The AFM image showed the morphologies of cylinder, sphere, and beads on a string owning to the random distribution of PHEA‐g‐PEG and PEG. A novel multiblock copolymer brush was synthesized by combining efficient DSPAAC and CuAAC click reactions. Firstly, polymer N3‐P(HEA‐alkyne)20‐N3was synthesized by SET‐LRP and subsequent deprotection, azidation and post‐modification reactions. Then the prepared polymer was reacted with N3‐PEG‐N3and DBA through DSPAAC click reaction to obtain the multiblock copolymer backbone (P(HEA‐alkyne)20)x‐co‐(PEG23)y. Finally, the multiblock copolymer brush (PHEA‐g‐PEG)x‐co‐(PEG23)ywas prepared by grafting the side chain onto the PHEA part of backbone through CuAAC click reaction.

Amine elimination of Ln[N(SiMe3)2]3(μ-Cl)Li(THF)3with aminophenol H[ON] {H[ON] = 2-(CH2NC5H10)-4,6-tBu2-C6H3OH} in 1:2 molar ratio in THF gave the monometallic rare-earth metal amide complexes [ON]2LnN(SiMe3)2(Ln = Yb (1), Y (2), Gd (3), Sm (4), Nd (5)) in 57%—73% isolated yields. All these complexes were characterized by elemental analysis. The molecular structures of complexes 1–4were determined by single crystal X-ray diffraction. These complexes are highly active for l-lactide polymerization to give high molecular weight polymers with unimodal molecular weight distributions. In addition, these complexes can also initiate rac-lactide polymerization with high activity to afford heterotactic-rich polylactides.

A modified PAA-Lix(0.25≤x≤1) binder with prominent mechanical properties and adhesion strength is specifically synthesized for durable SiO anodes by quantitatively substituting the carboxylic hydrogen with lithium.

This work reports the synthesis of core–shell structured Au@C composite through a simple one-step laser ablation technique. The results demonstrate that the Au@C with a mean nanosphere size of ∼8.0 nm is composed of a spherical shaped Au core and 1–2 layered graphitic carbon shell with abundant defects. As a nitrogen reduction reaction (NRR) electrocatalyst, the Au@C gives a large NH3yield rate of 241.9 μg h–1mgcat.–1with a high faradaic efficiency of 40.5% at −0.45 V versus reversible hydrogen electrode in a 0.1 M Na2SO4electrolyte (pH = 6.3) under ambient conditions, surpassing the performances of most aqueous-based NRR electrocatalysts recently reported. The 15N labeling experimental results demonstrate that the produced NH3is undoubtedly originated from the NRR process catalyzed by Au@C. The superior NRR performance of Au@C can be ascribed to the ultrathin carbon layer, effectively inhibiting the aggregation of Au nanospheres during the NRR, and the abundant defects such as carbon vacancies existed in the ultrathin carbon layer, providing additional NRR catalytic active sites. Our theoretical calculation results further confirm the role of carbon vacancies in the electrocatalytic NRR.

The chemical oxygen demand (COD) of waste water from bamboo heat treatment is mainly organic macromolecule compound which degraded from hemicellulos, lignin and extractives. COD is toxic to aquatic organism and human body and very difficult to degrade. The paper studied the possibility of pre-treating the bamboo heat treated waste water (BHTWW) by combination of iron-carbon micro electrolysis and Fenton method. Orthogonal experiment was designed with 3 factors: the initial pH value, retention time and H2O2dosage, and carried out with a dynamic sampling device with 2:1 iron carbon ratio. Results showed that the iron-carbon micro electrolysis and Fenton were proved to be a potential method in pre-treating BHTWW, and the optimum parameter should be pH 3.0, 40 min residence time and 0.5 % H2O2. After pre-treating, the removal rate of COD was 60.29 %, and B/C (biochemical oxygen demand after 5 days (BOD5)/COD increased from 0.037 to 0.32, the biodegradability was significantly improved. During the pretreatment, the nutrients in BHTWW had been oxidized, the double bound, conjugated double bond in guaiac lignin were opened or broken and degraded into more small molecular, nutrients such as TOC (total organic carbon) content, total nitrogen and total sugar content all decreased which all contributed for the increase of B/C. The microstructure of activated carbon appeared broken and collapses after pretreatment which indicated that they were eroded or involved during the micro electrolysis reaction.

Nanoscale field-effect transistors (FETs) represent a unique platform for real time, label-free transduction of biochemical signals with unprecedented sensitivity and spatiotemporal resolution, yet their translation toward practical biomedical applications remains challenging. Herein, we demonstrate the potential to overcome several key limitations of traditional FET sensors by exploiting bioactive hydrogels as the gate material. Spatially defined photopolymerization is utilized to achieve selective patterning of polyethylene glycol on top of individual graphene FET devices, through which multiple biospecific receptors can be independently encapsulated into the hydrogel gate. The hydrogel-mediated integration of penicillinase was demonstrated to effectively catalyze enzymatic reaction in the confined microenvironment, enabling real time, label-free detection of penicillin down to 0.2 mM. Multiplexed functionalization with penicillinase and acetylcholinesterase has been demonstrated to achieve highly specific sensing. In addition, the microenvironment created by the hydrogel gate has been shown to significantly reduce the nonspecific binding of nontarget molecules to graphene channels as well as preserve the encapsulated enzyme activity for at least one week, in comparison to free enzymes showing significant signal loss within one day. This general approach presents a new biointegration strategy and facilitates multiplex detection of bioanalytes on the same platform, which could underwrite new advances in healthcare research.

With the completion of the experimental and regional phases, China's BeiDou Navigation Satellite System (BDS) is being speedily expanded to a global and multifunctional satellite navigation system, BDS III. Confronted with challenges such as limited frequency resources and diversified user requirements, new signals with novel modulation techniques are adopted in BDS III. In addition to the legacy B1I and B3I signals, new open service signals, B1C and B2a/B2b, as well as some new authorized service signals, will be broadcast by BDS III satellites. Among them, B1C and B2a are compatible and interoperable with GPS and Galileo. The modulation techniques and the detailed signal structures of B1C and B2a are introduced in this paper, along with analysis of the initial in‐orbit test results of the new signals.

To develop and validate 3 radiomics nomograms for preoperative prediction of pathological and progression diagnosis in non-small cell lung cancer (NSCLC) as well as circulating tumor cells (CTCs). A total of 224 and 134 patients diagnosed with NSCLC were respectively gathered in 2018 and 2019 in this study. There were totally 1197 radiomics features that were extracted and quantified from the images produced by computed tomography. Then we selected the radiomics features with predictive value by least absolute shrinkage and selection operator and combined them into radiomics signature. Logistic regression models were built using radiomics signature as the only predictor, which were then converted to nomograms for individualized predictions. Finally, the performance of the nomograms was assessed on both cohorts. Additionally, immunohistochemical correlation analysis was also performed. As for discrimination, the area under the curve of pathological diagnosis nomogram and progression diagnosis nomogram in NSCLC were both higher than 90% in the training cohort and higher than 80% in the validation cohort. The performance of the CTC-diagnosis nomogram was somehow unexpected where the area under the curve were range from 60% to 70% in both cohorts. As for calibration, nonsignificant statistics (P > .05) yielded by Hosmer–Lemeshow tests suggested no departure between model prediction and perfect fit. Additionally, decision curve analyses demonstrated the clinically usefulness of the nomograms. We developed radiomics-based nomograms for pathological, progression and CTC diagnosis prediction in NSCLC respectively. Nomograms for pathological and progression diagnosis were demonstrated well-performed to facilitate the individualized preoperative prediction, while the nomogram for CTC-diagnosis prediction needed improvement.

•Mucins family, miR-93 and wnt pathway play an important role in the pathogenesis of intrahepatic stone.•Mucin3/4/5ac/B levels were found increased in patients with intrahepatic bile duct stones, and miR-93 levels were decreased.•Beta-catenin and wnt4 levels were higher also in subjects with intrahepatic bile duct stones.•Activition of wnt pathway up-regulated the expression of MUC4 and MUC5B, not MUC3 and MUC5ac.•miR-93 directly targeted TCF7 and repressed the activation of non-canonical, not canonical Wnt pathway.•miR-93 decreases the expression of MUC4/5ac/5B induced by wnt4.

A series of amine-bridged tris(phenolato) aluminum complexes L1Al-L7Al (1–7) were synthesized through alkane elimination reactions of amino-bridged tris(phenol)s (L1Al-L7Al) with AlMe3. Complexes 1–7were characterized through NMR, X-ray diffraction analysis, and elemental analysis. Their catalytic activities in the cycloaddition reaction of CO2and epoxides were studied. The chloro-substituted o-phenylenediamine-bridged tris(phenolato) aluminum complex 7exhibited the highest catalytic activity. Under the conditions of 1 bar CO2and 85 °C, complex 7/TBAB catalyzed the reaction of 15 monosubstituted epoxides with CO2, generating cyclic carbonates in 52–99% yields. Disubstituted epoxides were also transformed into cyclic carbonates in 60–99% yields in the presence of 10 bar CO2. Kinetic study of the cycloaddition of epichlorohydrin (ECH) and CO2revealed a zero-order dependence on CO2pressure and first-order dependence on the concentrations of ECH, complex 7, and TBAB.

Dinuclear aluminum methyl complexes stabilized by piperidyl–phenolato ligands were prepared and characterized. The ring-opening polymerizations of cyclohexene oxide (CHO) and propylene oxide (PO) initiated by dinuclear complexes and mononuclear analogues were investigated and compared. Enhanced activity of dinuclear complexes compared to that of mononuclear analogues in both the ring-opening polymerization of CHO and PO proves the synergistic interaction of two Al centers in the former. End-group analysis of oligomers by MALDI-TOF mass spectrometry confirms the role of methyl groups as initiating groups. A bimetallic mechanism is proposed, in which the cooperation of two Al centers are involved in polymerization processes.

Beta cell replication is the major component for maintenance of beta cell mass in adult rodents; however, little is known about what is the earliest signals that initiate rodent beta cell proliferation. The mTORC1 pathway integrates signals from growth factors and nutrients and regulates cell growth and survival. Here, we used normoglycemic 60 % partial-pancreatectomy (60 % Px) mouse model to determine whether mTORC1 pathway was required for compensatory beta cell proliferation. C57BL/6 J male mice were subjected to 60 % Px or sham operation, and subsequently treated with either rapamycin or vehicle for 7 days. Metabolic profile, pancreatic beta cell mass, and proliferation were examined, and expression levels of cell cycle regulators were determined. Beta cell proliferation was increased by 2.5-fold, and mTORC1 signaling was activated in islets post-Px. Rapamycin treatment impaired glucose tolerance and glucose stimulating insulin secretion in 60 % Px mice, but did not affect their insulin sensitivity in peripheral tissue. Rapamycin inhibited mTORC1 activity in beta cells, suppressed compensatory beta cell proliferation and growth, and reduced beta cell mass and insulin content in 60 % Px mice. Px caused an increase of the cyclin D2 at protein level and promoted cyclin D2 nuclear localization in an mTOR-dependent manner. Disrupting mTORC1 signaling suppressed cell proliferation and simultaneously diminished cyclin D2 protein abundance in RINm5F cells. Our data demonstrated that mTORC1 plays an essential role in beta cell adaption to significant beta cell mass loss in 60 % Px model and in early compensatory beta cell proliferation via cyclin D2 pathway.

The performance of flash memory is limited by its “erase-before-write,” and erase operations can only be performed in a much larger unit than write operations. To address these problems, we propose an efficient flash translation layer scheme called BLF: Block List Flash Translation Layer. BLF unites log blocks and physical blocks for servicing update requests. It can avoid uneven erasing and low block utilization. The address translation table of BLF can avoid storing an extra internal mapping table. BLF’s garbage collection method divides the storage zone into three levels: the active zone where hot data are stored, the inactive zone where cold data are stored, and the transitional zone where reclamation block is stored. If invalid blocks can be reclaimed properly and intensively, merging log blocks with physical blocks can be avoided and the amount of operations can be reduced. Finally, we implement an accurate flash simulator to evaluate the efficacy of BLF and compare it with other flash schemes, demonstrating that the improved performance resulting from BLF substantially outperforms other flash schemes.

AbstractRecent years have seen remarkable advancements in storage systems designed to carry data. The data reliability issue has become increasingly important, as certain adverse factors can impact storage systems and cause data loss. In this study, we developed a disk failure prediction model using disk SMART technology for disk-based storage systems. The proposed model works in a twofold process: first, a parameter reliability model is established based on the actual threshold and attribute values of the SMART parameters, (which we determined through theoretical discussion, then experimentation and analysis) and second, a disk reliability model is built according to the parameter reliability model and parameter weights as determined. The disk reliability failure threshold is then determined by analyzing the SMART parameter data and parameter weights in tandem with the disk reliability model to fully determine the level of disk reliability. This approach eventually allows the user to migrate low-level reliability disks to backup disks, thereby improving the overall reliability of the storage system. Experimental results proved that the proposed approach is feasible and effective.

Antibiotic resistance in bacteria, especially Gram-positive bacteria like Staphylococcus aureus, is gaining considerable momentum worldwide and unless checked will pose a global health crisis. With few new antibiotics coming on the market, there is a need for novel antimicrobial materials that target and kill multi-drug-resistant (MDR) Gram-positive pathogens like methicillin-resistant Staphylococcus aureus(MRSA). In this study, using a novel mixed-bacteria antimicrobial assay, we show that the star-peptide polymers preferentially target and kill Gram-positive pathogens including MRSA. A major effect on the activity of the star-peptide polymer was structure, with an eight-armed structure inducing the greatest bactericidal activity. The different star-peptide polymer structures were found to induce different mechanisms of bacterial death both in vitroand in vivo. These results highlight the potential utility of peptide/polymers to fabricate materials for therapeutic development against MDR Gram-positive bacterial infections.

Background. Robot-assisted pedicle screw placement is usually performed under general anesthesia to keep the body still. The aim of this study was to compare the accuracy of the robot-assisted technique under regional anesthesia with that of conventional fluoroscopy-guided percutaneous pedicle screw placement under general anesthesia in minimally invasive lumbar fusion surgery. Methods. This study recruited patients who underwent robot-assisted percutaneous endoscopic lumbar interbody fusion (PELIF) or fluoroscopy-guided minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) between December 2017 and February 2020 at a single center. Based on the method of percutaneous pedicle screw placement used, patients were divided into the robot-assisted under regional anesthesia (group RE-RO) and fluoroscopy-guided under general anesthesia (group GE-FLU) groups. The primary outcome measures were screw accuracy and the incidence of facet joint violation (FJV). Secondary outcome measures included X-ray and visual analogue scale (VAS) scores which were used to evaluate the degree of the postoperative pain at 4 hours and on postoperative days 1, 2, and 3. Intraoperative adverse events were also recorded. Results. Eighteen patients were included in group RE-RO, and 23 patients were included in group GE-FLU. The percentages of clinically acceptable screws (Gertzbein and Robbins grades A and B) were 94.4% and 91.5%, respectively. There was no significant difference in the percentages of clinically acceptable screws (p=0.44) or overall Gertzbein and Robbins screw accuracy grades (p=0.35). Only the top screws were included in the analysis of FJVs. The percentages of FJV (Babu grades 1, 2, and 3) were 5.6% and 28.3%, respectively. This difference was statistically significant (p=0.01). Overall, the FJV grades in group RE-RO were significantly better than those in group GE-FLU (p=0.009). The mean fluoroscopy time for each screw in group RE-RO was significantly shorter than that in group GE-FLU (group RE-RO: 5.4 ± 1.9 seconds and group GE-FLU: 6.8 ± 2.0 seconds; p=0.03). The postoperative pain between the RE-RO and GE-FLU groups was not statistically significant. The intraoperative adverse events included 1 case of registration failure and 1 case of guide-wire dislodgment in group RE-RO, as well as 2 cases of screw misplacement in group GE-FLU. No complications related to anesthesia were observed. Conclusion. Robot-assisted pedicle screw placement under regional anesthesia can be performed effectively and safely. The accuracy is comparable to the conventional technique. Moreover, this technique has the advantage of fewer FJVs and a lower radiation time.

Diels–Alder chemistry is a well-explored avenue for the synthesis of bioactive materials; however, its potential applications have recently expanded following the development of reactions that can be performed in buffered aqueous environments at low temperatures, including fulvene–maleimide [4 + 2] cycloadditions. In this study, we synthesized two novel amine-reactive fulvene linkers to demonstrate the application of this chemistry for generating mass spectrometry-cleavable labels (“mass tags”), which can be used for the labeling and detection of proteins. Successful conjugation of these linkers to maleimide-labeled peptides was observed at low temperatures in phosphate-buffered saline, allowing the non-destructive modification of proteins with such mass tags. The labile nature of fulvene–maleimide adducts in the gas phase also makes them suitable for both matrix-assisted laser desorption/ionization (MALDI) and electrospray ionization (ESI) mass spectrometric analysis. Unlike previous examples of MALDI mass tags, we show that fulvene–maleimide cycloaddition adducts fragment predictably upon gas-phase activation without the need for bulky photocleavable groups. Further exploration of this chemistry could therefore lead to new approaches for mass spectrometry-based bioassays.

•DM-FGD visualizes the wind turbine health state with SCADA data in real time.•The extracted Features present the manifold and clustering characteristics.•Health indicator describes the performance degradation process and potential abnormalities.•Clustering results of embedding features present changes in the health state.•DM-FGD can be extended to other dimensionality reduction algorithms.

Background. Symptomatic thoracic disc herniation is a challenge in spinal surgery, especially for cases with calcification. Traditional open operation has a high complication rate. The authors introduced a modified full-endoscopic transforaminal ventral decompression technique in this study and evaluated its imaging and clinical outcomes. Materials and Methods. Eleven patients with symptomatic thoracic disc herniation who underwent full-endoscopic transforaminal ventral decompression in a single medical center were enrolled. The surgical technique was performed as described in detail. Dilator sliding punching, endoscope-monitored foraminoplasty, and base cutting through the “safe triangle zone” are the key points of the technique. Clinical outcomes were assessed by the modified Japanese Orthopedic Association (mJOA) score for neurological improvement and the visual analogy score (VAS) for thoracic and leg pain. The operation time, hospital stay, and complications were also analyzed. Results. Postoperative magnetic resonance imaging (MRI) revealed good decompression of the spinal cord. The mJOA improved from 7.4 (range: 5–10) to 10.2 (range: 9–11). Axial thoracic pain improved in 8 of 9 patients. Leg pain and thoracic radicular pain improved in all patients. No complications were observed. The average operation time was 136 minutes (range: 70–180 minutes). The average length of hospital stay was 5.3 days (range: 2–8 days). Conclusion. Minimally invasive full-endoscopic transforaminal ventral decompression for the treatment of symptomatic thoracic disc herniation with or without calcification is feasible and may be another option for this challenging spine disease.

To combat the serious issue of increasing global antibiotic resistance, new antimicrobial therapies are urgently required. As one alternative, previously used antibiotics are being investigated for use in combination with more modern antibiotics including antimicrobial peptides. Towards this goal, 7‐aminocephalosporanic acid, the precursor to the conventional β‐lactam antibiotic, cephalosporin, and the related compound, 7‐aminodesacetoxycephalosporanic acid, were each chemically modified to enable their use in solid phase peptide synthesis for covalent conjugation via their 7‐amino group and a glycolic linker to the N‐terminus of a series of cationic antimicrobial peptides, MSI‐78, CA(1‐7)M(2‐9)NH2and des‐Chex1‐Arg20. Chemically functionalized Cα‐Fm‐protected 7‐aminocephalosporanic acid and 7‐aminodesacetoxycephalosporanic acid building blocks were separately prepared and attached by their 7‐amino group to the N‐terminus of each peptide on the solid phase via a glutaric anhydride linker. The resulting conjugated AMPs were assessed for antibacterial activity against a panel of six Gram‐negative bacteria, including clinically isolated multi‐drug resistant (MDR) pathogens. Only the conjugated MSI‐78 analogues displayed significant activity against Acinetobacter baumanniiand MDR A. baumannii 156and enhanced activity against Klebsiella pneumoniae. Further work is required to optimize the conjugation of AMPs to 7‐cephalosporanic acid and/or 7‐aminodesacetoxycephalosporanic acid to universally induce an enhanced effect on killing of drug sensitive and MDR bacterial strains that are common causes of hospital‐acquired infections.

In order to assess the performance of multisensor image registration algorithms that are used in the multirobot information fusion, we propose a model based on structural similarity whose name is vision registration assessment model. First of all, this article introduces a new image concept named superimposed image for testing subjective and objective assessment methods. Therefore, we assess the superimposed image but not the registered image, which is different from previous image registration assessment methods that usually use reference and sensed images. Then, we calculate eight assessment indicators from different aspects for superimposed images. After that, vision registration assessment model fuses the eight indicators using canonical correlation analysis, which is used for evaluating the quality of an image registration results in different aspects. Finally, three kinds of images which include optical images, infrared images, and SAR images are used to test vision registration assessment model. After evaluating three state-of-the-art image registration methods, experiments indict that the proposed structural similarity-motivated model achieved almost same evaluation results with that of the human object with the consistency rate of 98.3%, which shows that vision registration assessment model is efficient and robust for evaluating multisensor image registration algorithms. Moreover, vision registration assessment model is independent of the emotional factors and outside environment, which is different from the human.

It is found that a combination of TFA with the diamine shown is optimal.