Search

This study aimed to explore the prognostic and predictive value of autophagy-related lncRNAs in papillary thyroid carcinoma (PTC). The expression data of autophagy-related genes and lncRNAs of the PTC patients were obtained from TCGA database. Autophagy-related-differentially expressed lncRNAs (DElncs) were identified and used to establish the lncRNAs signature predicting patients’ progression-free interval (PFI) in the training cohort. Its performance was assessed in the training cohort, validation cohort, and entire cohort. Effects of the signature on I-131 therapy were also explored. We identified 199 autophagy-related-DElncs and constructed a novel six-lncRNAs signature was constructed based on these lncRNAs. This signature had a good predictive performance and was superior to TNM stages and previous clinical risk scores. I-131 therapy was found to be associated with favorable prognosis in patients with high-risk scores but not those with low-risk scores. Gene set enrichment analysis suggested that a series of hallmark gene sets were enriched in the high-risk subgroup. Single-cell RNA sequencing analysis suggested that the lncRNAs were mainly expressed in thyroid cells but not stromal cells. In conclusion, our study constructed a well-performed six-lncRNAs signature to predict PFI and I-131 therapy benefits in PTC.

To improve the dry friction behavior of traditional hard coatings, MoS2/PTFE lubricating coatings were prepared on the PVD TiN-coated cemented carbide using spray method. The influences of MoS2/PTFE lubricating coatings on the primary characteristics of TiN coatings were investigated. Reciprocating sliding tests were carried out with the TiN–MoS2/PTFE coated specimen (T-M-P) under dry sliding conditions, and the tribological behaviors were compared to those of the TiN-coated one (T-N). The test results indicated that the adhesion force of coatings with substrate for T-M-P specimen increased, the surface micro-hardness, roughness and friction coefficient significantly decreased. Meanwhile, the surface adhesions and abrasion grooves of T-M-P specimen were reduced, and the main wear forms of T-M-P were abrasion wear and coating delamination. The MoS2/PTFE lubricating coatings can be considered effective to improve the friction properties of traditional hard coatings.

The transient impact load during the launch of a rocket at sea threatens the safety of the launcher and the deck structure of the launch platform. In view of the impact resistance of the offshore rocket launcher system, this paper takes the real-scale rocket launcher system as the research object and establishes the analysis model of the fiber-reinforced composite rocket launcher based on the finite element method. Then, we explore the factors of the thickness by finite element simulation method and the angle and the position of IM7 fiber-reinforced composite, which influence the impact resistance property of the rocket launcher. The results show that the fiber-reinforced composite rocket launcher can effectively reduce the impact response of the structure and improve the impact resistance of the structure. The best laying scheme is to lay four layers of IM7 fiber material on both sides of the panels of the fixed bracket and the webs of the erector, respectively, with a single layer thickness of 0.75 mm and a laying angle of [90°/∓45°/90°].

Background and Aim: We aimed to explore risk factors and construct a model of MAFLD with fibrosis fibrosis and compare the performance of the panels of APRI, FIB-4 and BARD.Methods: We retrieved clinical information and enrolled 3671 patients. Subjects were assigned to four groups: MAFLD, MAFLD with fibrosis, and MAFLD with advanced fibrosis. Multivariate regression analysis and randomforest model were to construct the model of MAFLD with fibrosis, the receiver operating characteristics (ROC) were used to compare the diagnostic efficacy of predictive model, APRI, BARD, FIB-4. Results: ①The proportion of fibrosis in MAFLD was higher than that of non-MAFLD group; Compared with the control group, advanced fibrosis (≥F3) has no statistical significance. ②Four variables were selected to build the model of MAFLD. The diagnostic accuracy (AUROC=0.730) was superior to that of APRI and random forest model. ③Multivariate logistic analysis showed that increased BMI and AST was risk factors for advanced fibrosis and elevated PLT was a protective factor for advanced fibrosis; The diagnostic power of the model (AUROC=0.714) was superior to that of the FIB-4 and BARD.Conclusion: The model of fibrosis stage with MAFLD is superior to other non-invasive markers of fibrosis of MAFLD, which can assist clinicians in screening and warning for potential risks of MAFLD with fibrosis.

In order to improve the tribological behavior of Si3N4/TiC ceramics, DLC coating was fabricated on the ceramic surface through magnetron sputtering technology. The surface and cross-section micrographs, the adhesion between coating and substrate, the surface roughness and microhardness of the DLC-coated ceramics were investigated. Reciprocating friction tests sliding against cemented carbide ball were conducted under dry sliding conditions. The test results indicated that the DLC coating possessed superior tribological performance, which was conductive to decreasing the friction coefficient and enhancing the wear resistance of ceramics. The primary mechanisms responsible for performance improvement of the DLC-coated ceramics were attributed to the combined effects of low shear stress, excellent adhesion with substrate, high microhardness and good surface roughness. It was believed that the DLC coating was efficient in improving the load-carrying capacity and expanding the application area of ceramic materials.

To enhance the tribological performance of Si3N4/TiC ceramics, MoS2/PTFE composite coatings were deposited on the ceramic substrate through spraying method. The micrographs and basic properties of the MoS2/PTFE coated samples were investigated. Dry sliding friction experiments against WC/Co ball were performed with the coated ceramics and traditional ones. These results showed that the composite coatings could significantly reduce the friction coefficient of ceramics, and protect the substrate from adhesion wear. The primary tribological mechanisms of the coated ceramics were abrasive wear, coating spalling and delamination, and the tribological property was transited from slight wear to serious wear with the increase of load because of the lower surface hardness and shear strength. The possible mechanisms for the effects of MoS2/PTFE composite coatings on the friction performance of ceramics were discussed.

Stripping heavy atoms in solid matter of most of their electrons requires the extreme conditions that exist in astrophysical plasmas, but are difficult to create in the laboratory1–3. Here we demonstrate solid-density gold plasmas with atoms stripped of up to 72 electrons (N-like Au72+) over large target depths. This record ionization is achieved by irradiating solid foils and near-solid-density nanowire arrays with highly relativistic (3 × 1021 W cm−2) second-harmonic femtosecond laser pulses of '10 J energy focused into a 1.6 µm spot. The short wavelength and high intensity enable the interaction to occur at a relativistic critical density4,5 of 1023 cm−3. Solid targets reach a higher average charge in 1- to 2-µm-thick layers, while the less dense nanowire plasmas are heated to much larger depths ('8 µm) by energetic electrons generated near the nanowire tips. Larger laser spots could result in solid Au plasmas ionized up to He-like. Fil: Hollinger, R.. State University of Colorado - Fort Collins; Estados Unidos Fil: Wang, S.. State University of Colorado - Fort Collins; Estados Unidos Fil: Wang, Y.. State University of Colorado - Fort Collins; Estados Unidos Fil: Moreau, A.. State University of Colorado - Fort Collins; Estados Unidos Fil: Capeluto, Maria Gabriela. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Física de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Física de Buenos Aires; Argentina Fil: Song, H.. State University of Colorado - Fort Collins; Estados Unidos Fil: Rockwood, A.. State University of Colorado - Fort Collins; Estados Unidos Fil: Bayarsaikhan, E.. State University of Colorado - Fort Collins; Estados Unidos Fil: Kaymak, V.. Universitat Dusseldorf; Alemania Fil: Pukhov, A.. Universitat Dusseldorf; Alemania Fil: Shlyaptsev, V.N.. State University of Colorado - Fort Collins; Estados Unidos Fil: Rocca, J.J.. State University of Colorado - Fort Collins; Estados Unidos

In smart cities and factories, robotic applications require high accuracy and security, which depends on precise inverse dynamics modeling. However, the physical modeling methods cannot include the nondeterministic factors of the manipulator, such as flexibility, joint clearance, and friction. In this paper, the Semiparametric Deep Learning (SDL) method is proposed to model robot inverse dynamics. SDL is a type of deep learning framework, designed for optimal inference, combining the Rigid Body Dynamics (RBD) model and Nonparametric Deep Learning (NDL) model. The SDL model takes advantage of the global characteristics of classic RBD and the powerful fitting capabilities of the deep learning approach. Moreover, the parametric and nonparametric parts of the SDL model can be optimized at the same time instead of being optimized separately. The proposed method is validated using experiments, performed on a UR5 robotic platform. The results show that the performance of SDL model is better than that of RBD model and NDL model. SDL can always provide relatively accurate joint torque prediction, even when the RBD or NDL model is not accurate.

Generally, structural uncertainty of the robot dynamics system refers to model error caused by parameter identification, unstructured uncertainty is the unmodeled dynamic characteristic. No matter how elaborate modeling methods are used, there always be uncertainty. Therefore, this article applies deep learning for the first time to aid robot dynamic parameter identification of 6 degrees of freedom robot manipulator for compensation of uncertain factors. Firstly, the relatively accurate prediction of torque is obtained by the physical dynamic model using the parameters identification method (errors are less than 10% of the maximum torques). Secondly, we propose a novel deep neural network based approach called Uncertainty Compensation Model (UCM) to compensate the torque error introduced by the uncertainty. The UCM mainly composed by proposed Input Control Module (ICM) and Error Learning Models (ELMs) based on Long-Short-Term Memory and attention mechanism. The proposed ICM, which effectively avoids the unnecessary interference, is used to control valid input for ELMs. The ELMs, consisted by ELM units, concern extracting salient features from sequence data to predict the joint error. Also, this article summarizes the effects of valid input, timestep and attention mechanism on the performance of the UCM. Finally, the verification of parameter identification and torques compensation is carried out by a Universal Robot 5 manipulator. Compared with the prediction torques of physical dynamic model, the proposed UCM has a good ability to capture the friction characteristics and compensate for the error of local maximum torques, which effectively solves the deficiency of the physical dynamics model and improves prediction accuracy (errors are less than 6% of the maximum torques).

We present results from a pitcher-catcher experiment utilizing a proton beam generated with nanostructured targets at a petawatt-class, short-pulse laser facility to induce proton-boron fusion reactions in a secondary target. A 45-fs laser pulse with either 400 nm wavelength and 7 J energy, or 800 nm and 14 J, and an intensity of up to 5 × 1021 W/cm2 was used to irradiate either thin foil targets or near-solid density, nanostructured targets made of boron nitride (BN) nanotubes. In particular, for 800 nm wavelength irradiation, a BN nanotube target created a proton beam with about five times higher maximum energy and about ten times more protons than a foil target. This proton beam was used to irradiate a thick plate made of boron nitride placed in close proximity to trigger 11B (p, α) 2α fusion reactions. A suite of diagnostics consisting of Thomson parabola ion spectrometers, postshot nuclear activation measurements, neutron time-of-flight detectors, and differentially filtered solid-state nuclear track detectors were used to measure both the primary proton spectrum and the fusion products. From the primary proton spectrum, we calculated (p, n) and (α,n) reactions in the catcher and compare with our measurements. The nuclear activation results agree quantitatively and neutron signals agree qualitatively with the calculations, giving confidence that primary particle distributions can be obtained from such measurements. These results provide new insights for measuring the ion distributions inside of proton-boron fusion targets.

As world energy consumption intensifies, the oil and gas exploitation technology in the polar region are drawing more and more attention. However, due to the harsh environment, the oil and gas exploitation operation in the polar region are faced with enormous challenges, such as low temperature and sea ice collision, etc. This paper mainly focuses on the structural strength and integrity study of the arctic drilling riser suffering from the floe collision loading. First, the discrete element software IceDEM is employed to develop a local drilling riser - sea ice interaction model subjected to the floe collision loading in the splash zone, and the corresponding dynamic collision response between the drilling riser and the floe ice could be calculated and acquired. Then, a global drilling riser model is built within the framework of general finite element analysis software ABAQUS to investigate the dynamic behavior of the arctic drilling riser in the polar environment, and the dynamic collision loading derived from IceDEM simulation is also introduced in this global model. Finally, the dynamic responses of the arctic drilling riser based on the finite element simulation are investigated to research the riser’s security and integrity, which can provide reference for the design and application of the drilling riser in the polar region.

The properties of the MoS2/Zr coatings can be significantly affected by the deposition temperature. In this study, the MoS2/Zr composite coatings were fabricated on the cemented carbide surface, utilizing the duplex deposition technology at various deposition temperatures. The effects of deposition temperature on the mechanical and friction properties of the MoS2/Zr coatings were systematically studied. Results exhibited that as the deposition temperature increased, the adhesion force increased first and then decreased, and the coating thickness and micro-hardness gradually increased. Dry sliding tests against a hardened steel ring showed that the tribological behaviors and wear mechanisms of the MoS2/Zr coatings varied with deposition temperature, which were due to the changing mechanical properties of coatings caused by the temperature. The coatings deposited at a temperature of 180 °C and 200 °C possessed preferable comprehensive mechanical and tribological properties.

The properties of the MoS2/Zr coatings can be significantly affected by the deposition temperature. In this study, the MoS2/Zr composite coatings were fabricated on the cemented carbide surface, utilizing the duplex deposition technology at various deposition temperatures. The effects of deposition temperature on the mechanical and friction properties of the MoS2/Zr coatings were systematically studied. Results exhibited that as the deposition temperature increased, the adhesion force increased first and then decreased, and the coating thickness and micro-hardness gradually increased. Dry sliding tests against a hardened steel ring showed that the tribological behaviors and wear mechanisms of the MoS2/Zr coatings varied with deposition temperature, which were due to the changing mechanical properties of coatings caused by the temperature. The coatings deposited at a temperature of 180 °C and 200 °C possessed preferable comprehensive mechanical and tribological properties.

Metabolic syndrome (MetS) is a wide-ranging disorder, which includes insulin resistance, altered glucose and lipid metabolism, and increased blood pressure and visceral obesity. MetS symptoms combine to result in a significant increase in cardiovascular risk. It is therefore critical to treat MetS in the early stages of the disorder. In this study, 123 MetS patients and 304 controls were recruited to determine whether the gut microbiome plays a role in MetS development and progression. By using whole-genome shotgun sequencing, we found that the gut microbiomes of MetS patients were different from those of controls, with MetS patients possessing significantly lower gut microbiome diversity. In addition, 28 bacterial species were negatively correlated with waist circumstance, with Alistipes onderdonkii showing the strongest correlation, followed by Bacteroides thetaiotaomicron, Clostridium asparagiforme, Clostridium citroniae, Clostridium scindens, and Roseburia intestinalis. These species were also enriched in controls relative to MetS patients. In addition, pathways involved in the biosynthesis of carbohydrates, fatty acids, and lipids were enriched in the MetS group, indicating that microbial functions related to fermentation may play a role in MetS. We also found that microbiome changes in MetS patients may aggravate inflammation and contribute to MetS diseases by inhibiting the production of short-chain fatty acids (SCFAs). Taken together, these results indicate the potential utility of beneficial gut microbiota as a potential therapeutic to alleviate MetS.

High-energy ultrashort pulse optical lasers operating at high repetition rate are required to drive intense compact coherent soft X-ray sources, including soft X-ray lasers, for applications in nanoscience and nanotechnology, material studies, and high field science. This paper reviews two types of high-power solid-state laser systems developed at Colorado State University to pump compact, high repetition rate, and plasma-based soft X-ray lasers. One is a flashlamp-pumped, petawatt-class Ti:sapphire chirped-pulse amplification laser that generates 0.85 PW pulses of 30 fs duration at 3.3 Hz repetition rate. Using a fraction of the output energy from this laser, we have demonstrated gain-saturated, compact, repetitive lasers down to 6.85 nm in Ni-like Gd and have observed gain in shorter wavelength transitions, down to 5.85 nm in Ni-like Dy. The second type of pump laser is an all diode-pumped chirped-pulse amplification system based on cryogenically cooled Yb:YAG active mirror amplifiers that produces 1 J pulses of picosecond duration at 500 Hz repetition rate. These compact diode-pumped laser systems have enabled new advances in high-average-power tabletop soft X-ray lasers that include 100 Hz demonstrations at wavelengths ranging from 10.9 to 18.9 nm, as well long duration operation at these high repetition rates for periods up to one hour. These and other recent results that include the operation of an 18.9 nm laser Ni-like Mo laser at 400 Hz repetition rate open a path to compact kilohertz repetition rate soft X-ray lasers.

OBJECTIVE: In this study we investigated the effect of dorsomedial hypothalamus (DMH) neuropeptide Y (NPY) knock-down on hepatic insulin sensitivity in high-fat (HF) diet-fed rats. METHODS: Forty-eight Sprague-Dawley rats were randomly assigned to receive bilateral DMH injections of adeno-associated virus AAVshNPY or AAVshCTL and then accessed to regular chow. Five weeks after viral injection, half rats in each group were given access to the HF diet. At 16 weeks, rat livers were collected. Insulin receptor substrate-1 (IRS-1) and phosphoinositide 3-kinase (PI3K) mRNA expression was measured by qRT-PCR. Blood glucose levels were measured by the oxidase method, serum insulin, triglyceride, and TC levels were measured by Elisa. Pathological changes in the liver were assessed by hematoxylin-eosin (HE) staining. AKT, p-AKT, and GSK-3 levels were measured by western blotting. RESULTS: Compared with AAVshCTL-injected rats, AAVshNPY-injected rats showed a significant decrease in blood glucose concentrations; serum insulin, triglyceride, and TC; HOMA-IR; and IRS-1 and PI3K mRNA levels (P

In smart cities and factories, robotic applications require high dexterity and security, which requires precise inverse dynamics model. However, the physical modeling methods cannot model the uncertain factors of the manipulator such as flexibility, joint clearance and friction, etc. As an alternative, artificial intelligence (AI) techniques have become increasingly popular in robotics for smart cities and factories. In this paper, deep learning neural network based on LSTM (Long Short-Term Memory) is adopted to predict the manipulator inverse dynamics. This study aims to summarize the influence of the hyper-parameter settings on model performance and to explore the applicability of the LSTM model to joint torque prediction of multiple degrees of freedom series manipulator. Furthermore, the feasibility of using only joint position as input data for torque prediction is verified. Simulation result has shown that, for the proposed deep learning architecture, the effects of the number of maximum epochs on model performance should be prioritized. The effects of the number of hidden nodes on model performance are limited, while prediction accuracy will deteriorate as the number of hidden layers increases. It is proved that it is feasible to predict inverse dynamics when input data is joint position only. The experimental results show that the training time increases with the increase of hidden layers, neurons and epochs.

Currently, the pathogenesis of acute myelocytic leukemia(AML) is still unclear. We found the core genome M5C plays a vital role in methylation modification and immune infiltration of AML. At the same time, we created a new M5C score model to define the high and low-risk groups of AML.Our research showed the expression levels of the three molecular subtypes of M5C (C1, C2 and C3);as well as different clinical features ,the results showed significant differences in age\RUNX1-RUNX1T1 fusion, but not in RUNX1 mutation group.We constructed a prognostic risk model based on m5C phenotype from 417 samples in the GSE37642 data set and found 5 differential genes using lasso regression method. And the prognostic KM curve of the 5-gene signature was obtained, from which it can be seen that: all the five genes could significantly reduce the high and low risk of GSE37642 training set samples (P

Obesity, especially abdominal obesity, is correlated to increased risk of cardiovascular morbidity and mortality. It is urgent to search a simply method to predict visceral fat area (VFA). Herein, we evaluated the correlation of waist circumference (WC) measured by anthropometry and bioelectrical impedance analysis (BIA), and VFA estimated by BIA or measured by quantitative computed tomography (QCT) in China. The mean body mass index (BMI) was 25.09 ± 3.31 kg/m2 and the mean age was 49.16 ± 9.19 years in 2754 subjects. VFA-BIA were significantly smaller than VFA-QCT in both BMI and age subgroups between male and female (p r = 0.874 for all, r = 0.865 for male and r = 0.806 for female) and for VFA between BIA and QCT (r = 0.512 for all). The intraclass correlation coefficient (ICC) showed the perfect agreement between BIA and manually to measure WC (ICC = 0.832 for all, 0.845 for male and 0.697 for female) and implied a good reliability for VFA between BIA and QCT with women among subgroups (ICC = 0.623 for all, ICC = 0.634 for age 24 kg/m2), whereas the good reliability was lost in men (ICC = 0.174). The kappa analysis showed a moderate consistency for VFA measured by BIA and QCT (Kappa = 0.522 with age r = 0.758 in male, r = 0.727 in female, P 2, 119.96 cm2 and 118.83 cm2 and the Youden’s index was 0.577, 0.577 and 0.651, respectively and the Kappa value was 0.532, 0.536 and 0.611 in unadjusted model, model 1 and model 2. In conclusion, being non-invasive and free of radiation, BIA can be used as a safe and convenient tool to estimate VFA in female; especially for monitoring the VFA of the same person, the BIA has superiority to a certain extent. However, the consistency is not most ideal between BIA and QCT. When using BIA to assess whether a person is visceral obesity, we must take into consideration age, BMI and WC. Therefore, we established a regression formula to reflect VFA-QCT by VFA-BIA, age, BMI, and WC. In addition, a more accurate formula is needed to match the CT data in China.

It is challenging to obtain nanoscale resolution images in a single ultrafast shot because a large number of photons, greater than 1011, are required in a single pulse of the illuminating source. We demonstrate single-shot high resolution Fourier transform holography over a broad 7 µm diameter field of view with ∼ 5 ps temporal resolution. The experiment used a plasma-based soft X-ray laser operating at 18.9 nm wavelength with nearly full spatial coherence and close to diffraction-limited divergence implemented utilizing a dual-plasma amplifier scheme. A Fresnel zone plate with a central aperture is used to efficiently generate the object and reference beams. Rapid numerical reconstruction by a 2D Fourier transform allows for real-time imaging. A half-pitch spatial resolution of 62 nm was obtained. This single-shot nanoscale-resolution imaging technique will allow for real-time ultrafast imaging of dynamic phenomena in compact setups.

Background: Since December 2019, a new strain of coronavirus named 2019 novel coronavirus (2019-nCoV) has been discovered in Wuhan. The prevalence of diabetes mellitus, which is a great public health issue leading to immunity inhibition and an increased incidence of infections, has been increasing over the past ten years. The aim of this research was to systematically assess the prevalence of diabetes mellitus among 2019-nCoV. Methods: We searched PubMed, Embase, Web of Science and Medline for observational studies up to February 25, 2020. A random effects model or fixed-effects model was applied to evaluate the pooled prevalence of diabetes mellitus and odds ratio (OR) with 95% confidence interval (CI). Findings: In total, nine papers met the eligibility criteria. The pooled prevalence of DM was 9% (95% CI 6%–12%). There was obvious heterogeneity (I 2 65%, p=0.004) in the prevalence of DM in these studies. The prevalence of DM in moderate patients with 2019-nCoV was 7% (95% CI 4%–10%). The prevalence of DM in severe patients with 2019-nCoV was 17% (95% CI 13%–21%). The prevalence of DM in severe patients with 2019-nCoV was significantly higher than that in moderate patients with 2019-nCoV (OR 2.49, 95% CI 1.70 to 3.64). Interpretation: To our knowledge, this work is the first report showing the prevalence of diabetes mellitus in patients with 2019-nCoV, which is beneficial to prevent the spread of 2019-nCoV in the future. Funding Statement: Natural Science Foundation of Henan Province of China (Grant number: 162300410306). Declaration of Interests: None.

We report a significant enhancement in both the energy and the flux of relativistic electrons accelerated by ultra-intense laser pulse irradiation (>1 10 21 W cm-2) of near solid density aligned CD2 nanowire arrays in comparison to those from solid CD2 foils irradiated with the same laser pulses. Ultrahigh contrast femtosecond laser pulses penetrate deep into the nanowire array creating a large interaction volume. Detailed three dimensional relativistic particle-in-cell simulations show that electrons originating anywhere along the nanowire length are first driven towards the laser to reach a lower density plasma region near the tip of the nanowires, where they are accelerated to the highest energies. Electrons that reach the lower density plasma experience direct laser acceleration up to the dephasing length, where they outrun the laser pulse. This yields an electron beam characterized by a 3 higher electron temperature and an integrated flux 22.4 larger respect to foil targets. Additionally, the generation of >1 MeV photons were observed to increase up to 4.5. Fil: Moreau, A.. State University of Colorado - Fort Collins; Estados Unidos Fil: Hollinger, R.. State University of Colorado - Fort Collins; Estados Unidos Fil: Calvi, C.. State University of Colorado - Fort Collins; Estados Unidos Fil: Wang, S.. State University of Colorado - Fort Collins; Estados Unidos Fil: Wang, Y.. State University of Colorado - Fort Collins; Estados Unidos Fil: Capeluto, Maria Gabriela. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Física de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Física de Buenos Aires; Argentina Fil: Rockwood, A.. State University of Colorado - Fort Collins; Estados Unidos Fil: Curtis, A.. State University of Colorado - Fort Collins; Estados Unidos Fil: Kasdorf, S.. State University of Colorado - Fort Collins; Estados Unidos Fil: Shlyaptsev, V.N.. State University of Colorado - Fort Collins; Estados Unidos Fil: Kaymak, V.. Universitat Dusseldorf; Alemania Fil: Pukhov, A.. Universitat Dusseldorf; Alemania Fil: Rocca, J.J.. State University of Colorado - Fort Collins; Estados Unidos

Nuclear fusion is regularly created in spherical plasma compressions driven by multi-kilojoule pulses from the world’s largest lasers. Here we demonstrate a dense fusion environment created by irradiating arrays of deuterated nanostructures with joule-level pulses from a compact ultrafast laser. The irradiation of ordered deuterated polyethylene nanowires arrays with femtosecond pulses of relativistic intensity creates ultra-high energy density plasmas in which deuterons (D) are accelerated up to MeV energies, efficiently driving D–D fusion reactions and ultrafast neutron bursts. We measure up to 2 × 106 fusion neutrons per joule, an increase of about 500 times with respect to flat solid targets, a record yield for joule-level lasers. Moreover, in accordance with simulation predictions, we observe a rapid increase in neutron yield with laser pulse energy. The results will impact nuclear science and high energy density research and can lead to bright ultrafast quasi-monoenergetic neutron point sources for imaging and materials studies., Neutron beams are useful studying fundamental physics problems, fusion process and material properties. Here the authors use intense laser irradiation of deuterated nanowire array targets to create high energy density plasmas capable of efficient generation of ultrafast neutron pulses.

We propose a simple but effective implicit-surface-based (ISB) method for constructing composite porous scaffolds (including gradient, hybrid, hierarchical, stochastic porous structures, or their combinations) based on a certain number of control elements (points, line segments, polylines, polygons, etc.) that are provided by users. Our method efficiently integrates spatial partitioning and substructure assignments in an easy manner. Users need not consider complex transitions between substructures during design, as these are naturally constructed. Also, our method can easily reconstruct native tissue structures based on micro-CT data. Here we successfully fabricated porous scaffolds with polymer as well as titanium using additive manufacturing (AM) techniques for ready use in tissue engineering.

The Chinese Nuclear Society (CNS) congratulates readers, reviewers, and editors of the ASME Journal of Nuclear Engineering and Radiation Science (ASME J. of NERS) and nuclear experts and specialists all around the world with significant achievements and new milestones in nuclear-power industry!

Polyethersulfone (PES) and polytetrafluoroethylene (PTFE) blend composites reinforced with sodium–montmorillonite (Na–MMT) nanoparticles were prepared by cold molding and vacuum sintering. The effects of the Na–MMT content on the thermal, nanomechanical, and tribological properties of the Na–MMT/PES/PTFE ternary composites were investigated in detail. The results indicate that at the optimal content, Na–MMT nanoparticles can be uniformly dispersed in the PES/PTFE binary blend composites and generate strong interfacial bonding with the polymeric matrix. Both the thermal stability and the nanomechanical properties of the PES/PTFE binary blend composites are clearly improved by the incorporation of Na–MMT nanoparticles. Among these PTFE-based composites, the Na–MMT/PES/PTFE ternary composite containing 10.0 wt^ of Na–MMT nanoparticles exhibits the optimal friction and wear performance. Compared with those of the PES/PTFE blend composite, the friction coefficient (μ = 0.16) and wear rate (k = 2.63 × 10−14 m3/(N·m)) of the 10.0 wt^ Na–MMT/PES/PTFE ternary composite are 19.1^ and 97.2^ lower, respectively. The significant enhancement of the wear resistance of the Na–MMT/PES/PTFE ternary composite is attributable to the formation of PTFE self-lubricating transfer films. The transfer films generated on the worn surfaces of GCr15 steel balls can prevent direct contact between the PTFE composites and their metal counterparts, thereby protecting the polymer composites from damage.

To improve the tribological properties of pure MoS2 coating, the MoS2&ndash, Zr composite lubricating coatings were prepared on the WC/TiC/Co carbide surface utilizing radio frequency magnetron sputtering method combining with multiple arc ion plating technology. The effects of different Zr target currents on the surface morphologies, roughness, Zr content, adhesive force, thickness, microhardness and tribological behaviors of the composite coatings were systematically investigated. Results showed that the properties of MoS2 coating can be remarkably enhanced through co-deposition of a certain amount of Zr. As the Zr target current increased, the Zr content, surface roughness, thickness, and micro-hardness gradually increased, while the adhesive force of coatings increased first and then decreased. The friction behaviors and wear modes of the composite coatings both varied obviously with the increase of Zr current. The mechanism was mainly attributed to the different components and mechanical properties of the coatings caused by various Zr current.

To enhance the friction and wear performance of cemented carbide, textured microholes were machined on micro Electron Discharge Machining (EDM) on the tool rake face, and Calcium Fluoride (CaF2) powders were burnished into the microholes. The friction and wear characteristics of the microhole-textured tool filled with CaF2 were investigated using sliding friction tests and dry cutting tests. Results exhibited that the working temperature could affect the tribological performance of the microhole-textured tool filled with CaF2 due to the temperature-sensitive nature of CaF2. There is no obvious lubrication effect for the textured tool filled with CaF2 at room temperature, while it was shown to be more effective in improving tribological property at a cutting speed of higher than 100 m/min with a corresponding to cutting temperature of 450 &deg, C. The possible mechanisms for the microhole-textured tool filled with CaF2 were discussed and established.