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In this paper, SiCp/TC11 titanium matrix composites were prepared by selective laser melting. The influence of laser process parameters on the forming quality of composites was studied by control variable method. The results show that the process parameters have a significant effect on the forming quality of the composite material. The laser power has the greatest influence on the density, followed by the scanning spacing, and the scanning speed has a relatively small influence. When the laser power is 160 ~ 180 W, the scanning speed is 1 000 ~ 1 200 mm/s, and the scanning spacing is 0,1 mm, the forming quality of the sample is better.

Rare earth electrolysis robot is an automatic equipment that can realize the process of crucible extraction and dumping of casting mold in electrolytic tank under high temperature and dusty environment. Based on ANSYS software and APDL language, the thermal-structural coupling simulation analysis of the rare earth electrolysis robot is carried out to construct the temperature distribution and thermal deformation model of the robot, and the thermal deformation error and connecting rod machining error are considered comprehensively to obtain the linkage length dimension error model, which provides some theoretical basis for the robot error compensation to improve the accuracy.

In order to improve the comprehensive performance of titanium alloy, the mechanical ball milling method was used to optimize the preparation of composite powder by different ball milling time, rotation speed and SiCp content. SiCp/TC11 composites were prepared by selective laser melting (SLM) technology. The results show that the milling speed, time and SiC content have an effect on the morphology, size and distribution of the composite powder. Compared with TC11, the hardness of the composite prepared by SLM process is 426,723 HV, which is increased by 15,10 %, and the enhancement effect of SiCp is successfully realized.The research results provide a theoretical basis for obtaining high-quality aerospace titanium alloy parts.

This paper mainly studies the influence of process parameters on the forming quality during the spinning process of 6061 aluminum alloy wheel forging blanks. The four parameters of spinning temperature, spindle speed, wheel feed and wall thickness reduction rate are selected for research, and the quality of the surface of the hub and the influence on the size of the hub are judged. Simufact software is used to simulate the influence of various process parameters on the forming quality of the hub. The results provide a certain reference for the reasonable selection of process parameters during the spinning forming process of 6061 aluminum alloy hub.

The influence of electron cyclotron wave (ECW) injection with different deposition positions and injection powers on the evolution of peeling–ballooning (P–B) modes is studied with the BOUT++ code, in which the energy deposition and current drive of the ECW are calculated using a ray tracing code. It is shown that the changes in the profiles of plasma pressure, current density, and resistivity induced by ECW injection can significantly influence the linear property and the nonlinear evolution of P–B modes. For the linear simulation, the ECW deposited at the top of the pedestal makes the high toroidal mode number (n) P–B modes more unstable; however, it stabilizes the medium-n to high-n P–B modes when the ECW is deposited at the middle of the pedestal, and the ECW deposited at the bottom of the pedestal decreases the growth rate of P–B modes with medium-n. Further investigation shows that the injected ECW influences the characteristic of linear P–B modes by changing the diamagnetic effect, magnetic shear, pressure gradient, current density, resistivity, and so on. It is known from the nonlinear simulation that the energy loss caused by the edge localized mode (ELM) with ECW injection deposited at the top of the pedestal is nearly the same as that in the case without ECW injection, while the ECW deposited at the middle and bottom of the pedestal is helpful to decrease ELM energy loss. According to the analyses of the time evolution of the P–B mode toroidal spectrum, the physical mechanism of the decrease in ELM energy loss in the simulation is that ECW injection suppresses the most unstable toroidal harmonic of the P–B mode. On the other hand, the influence of ECW injection on P–B modes becomes more obvious when the power of the injected ECW increases. Moreover, the influence of current driven by the ECW on P–B modes is studied separately in this paper, which plays a different role from the bootstrap current.

The changes of hardening depth and surface hardness of C45 steel after laser surface quenching were studied. Firstly, the Nd: YAG laser and CO2 laser were used to realize the surface quenching. High power CO2 laser quenching C45 steel, variable process parameters include power, scanning speed and defocusing distance. Then, the Nd:YAG laser was used to quench the samples through orthogonal experiments, and the optimized process parameters were obtained, and the surface hardness was obviously improved. Finally, by comparing the quenching C45 steel of CO2 laser, the influence curve of process parameters on surface hardness was found, and the optimal process parameters were obtained.

The temperature effect on the mechanical behavior of the HfNbTaTiZr high entropy alloy (HEA) was investigated at 77–673 K. The decrease of the yield strength with increasing the temperature was mechanistically analyzed by considering contributions from various strengthening mechanisms. An anomalous dependence of strain hardening on temperature was observed and was justified to be caused by dynamic strain aging (DSA) as an extra strengthening mechanism at elevated temperatures. A model was constructed to split the overall strain hardening into forest hardening and DSA hardening, both of which were theoretically quantified at all temperatures considered.

Based on the magnetic field configuration of the Chinese First Quasi-axisymmetric Stellarator (CFQS) device, three types of orbits such as the passing orbit, blocked trapped orbit, and localized trapped orbit are simulated using the Boris algorithm. Also, the orbital topology, orbit transition, and loss characteristics of these particles under different initial conditions are studied in this paper. It is found that there exists a transition from blocked trapped orbits to localized trapped orbits due to small continuous helical ripples. This phenomenon is analyzed as follows: we define the angle between the particle drift velocity (v→D) and the radial direction (ρ^) as β. If the blocked-localized transition appears in the region where β>90○, the localized particles will return to the blocked particles and be constrained. However, if the blocked-localized transition happens in the region where β

Interfacial properties between metal back contacts and solar cell absorbers play important roles in determining efficiencies, but studies of such properties in CZTS and CZTSe based solar cells are quite lacking from theoretical aspects. To fill such a blank and explore insights for improving energy conversion efficiencies, we have studied interfacial properties in CZTS and CZTSe solar cells. The natural band offsets between CZTX and the spontaneously formed MoX2 layer (X = S, Se) are obtained using our recently developed intermediate-phase method. We find that the band alignment between CZTS and MoS2 is actually harmful while the band alignment between CZTSe and MoSe2 is beneficial for carrier extractions. We further propose to engineer the back contact interface to improve CZTS solar cell efficiency by depositing a thin layer of Se on the Mo back contact prior to the CZTS deposition, thus avoiding the formation of the undesirable MoS2 layer.

A novel approach for positron injection and acceleration in the laser driven plasma wakefield is proposed. One ring-shaped beam and one coaxially propagating Gaussian beam drive wakefields in a preformed plasma volume filled with both electrons and positrons. The laser’s ponderomotive force as well as the charge separation force in the front bucket of the first bubble are utilized to provide the transverse momenta of injected positrons and those positrons can be trapped by the focusing field and then accelerated by the wakefield. Theoretical analysis of the process is presented and verified by particle-in-cell simulations. The simulations show that relatively high-charge, quasimonoenergetic positron beams can be obtained.

Cellular retinol-binding protein II (CRBP II) belongs to the family of cellular retinol-binding proteins and plays a major role in absorption, transport, and metabolism of vitamin A. In addition, because vitamin A is correlated with reproductive performance, we measured CRBP II mRNA abundance in erlang mountainous chickens by real-time PCR using the relative quantification method. The expression of CRBP II showed a tissue-specific pattern and egg production rate-dependent changes. The expression was very high (p

Native chickens hold a significant share of the market in China. In response to the huge demand from the market, the productivity of Chinese native chickens needs to be improved. Cross breeding is an effective method to increase productivity, although it might affect meat quality. In this study, two pure lines (SD02 and SD03) of Erlang mountainous chickens were hybridized with a yellow feather and faster growing line (SD01). The effect of hybridization on carcass and meat quality (physiochemical and textural traits) was measured in the F1 population at d 91 of age. The hybrids exhibited higher body weight and dressed weight, and amount of semi-eviscerated, eviscerated, breast muscle and abdominal fat (p

FORMOSAT-7/COSMIC-2 radio occultation (RO) measurements show promise for observing the deep troposphere and for providing critical information on the Earth's planetary boundary layer (PBL). However, refractivity retrieved in the low troposphere can have severe biases under certain thermodynamic conditions. This research examines the characteristics of the deep tropospheric biases and presents methods for estimating the region-dependent refractivity bias using statistical regression models. The results show that the biases have characteristics that vary over land and oceans. With substantial correlation between local spectral width (LSW) and bias, the LSW-based bias estimation model can explain the general pattern of the refractivity bias but with deficiencies in measuring the bias in the ducting regions and in certain areas over land. The estimation model involving the relationship with temperature and specific humidity (TQ) can capture the large biases associated with ducting. Finally, a minimum variance estimation that combines the LSW and TQ provides the most accurate estimation of the refractivity bias.

A 52-year-old man visited our hospital complaining of anorexia and fatigue two months after receiving orthotopic liver transplantation for hepatocellular carcinoma. A laboratory investigation demonstrated a clinical picture of obstructive jaundice. T-tube cholangiography showed biliary stricture over the anastomotic site. Percutaneous transluminal balloon dilatation and stenting was attempted but failed. Magnetic resonance cholangiography showed possible tumor recurrence over the site of the anastomotic biliary stricture. A biopsy sample was obtained via ultrasound-guided aspiration and histopathological study revealed inflammatory and fibrotic changes. With high suspicion of recurrence of the hepatocellular carcinoma, surgical exploration was performed and an intraoperative frozen section proved the recurrence. We thus diagnosed this case as a recurrence of hepatocellular carcinoma after liver transplantation. To our knowledge, there have been no previous reports of early tumor recurrence after liver transplantation being the cause of an anastomotic biliary stricture.Un varón de 52 años visitó nuestro hospital quejándose de anorexia y fatiga a los dos meses de haber recibido un trasplante hepático ortotópico a causa de un carcinoma hepatocelular. La analítica mostró un cuadro clínico de ictericia obstructiva. La colangiografía con tubo en T mostró una estenosis biliar sobre la anastomosis. Se intentó una dilatación transluminal percutánea con globo y colocación de endoprótesis, que fracasó. La colangiografía por resonancia magnética mostró una posible recurrencia tumoral sobre el lugar de la estenosis biliar anastomótica. Se extrajo una muestra de biopsia mediante aspiración bajo guía ecográfica y el estudio histopatológico mostró alteraciones inflamatorias y fibróticas. Al sospecharse la recurrencia del carcinoma hepatocelular, se realizó una exploración quirúrgica; un corte intraoperatorio congelado demostró dicha recurrencia. Así, diagnosticamos este caso como la recurrencia de un carcinoma hepatocelular después de un trasplante de hígado. Que sepamos, no se ha publicado anteriormente ninguna recurrencia tumoral precoz posterior a un trasplante hepático que fuera causa de estenosis biliar anastomótica.

Non-speaking autistic individuals grapple with the profound impact of the ‘double empathy problem’ in their daily interactions with speaking others. This study rethinks the communication challenges faced by non-speaking autistic individuals, challenging traditional approaches that predominantly focus on speech and complex communication devices (AAC). By spotlighting the natural phenomenon of “interactive stimming,” a powerful mode of communication among autistic individuals, this study advocates for a shift from a conventional emphasis on speech towards the foundational role of the body in autistic communication. Central to this exploration is the introduction of the Magical Musical Mat (MMM), an innovative interactive environment mapping interpersonal touch to musical sounds. Through a robust mixed-methods approach integrating video-based fieldwork and design-based research, this paper engages three non-speaking autistic children and their mothers in a 5-day empirical intervention. Results reveal significant transformations in parent–child interactions as both parents and children are acquainted with touch in a new environment. Children assert their autonomy, exploring at their own pace, and discovering sensory features of the environment. Notably, the introduction of sound prompts heightened awareness of the stims, leading to diversified and expressive stim movements. Foregrounding interpersonal touch eventually guides parents into their children’s sensory activities where parents attune to the stims of their children by joining in and facilitating their expressiveness, co-creating extended, evolving patterns of repetitive cycles. The collaborative stim cycles can be likened to free improvisation, where dynamical coherence between individuals occurs through a blend of stability and active flexibility. By shifting the focus from speech to co-created sensory experiences, this paper sheds light on the value of transformative multisensory environments, envisioning a world where varied modes of communication are valued and embraced.

Arctium lappa and A. tomentosum are known medicinal plants in China. The complete chloroplast genomes from A. lappa and A. tomentosum were sequenced using Illumina sequencing technology. The total genome sizes of the complete chloroplast genomes of A. lappa and A. tomentosum were 152 767 bp and 152 688 bp, respectively, and contained a pair of inverted repeats of the same length (15,181 bp). The small single-copies were 18 584 bp and 18 582 bp, and the large single-copies were 83 821 bp and 83 744 bp, respectively. We identified and annotated 134 and 126 genes from A. lappa and A. tomentosum including, respectively, 90 and 89 protein-coding genes, 36 and 29 tRNAs, and eight rRNAs. A. lappa was found to have 10 tRNAs different from those in A. tomentosum, and A. tomentosum had three tRNAs different from those in A. lappa. There were only two types of simple sequence repeats of two species, mononucleotide and dinucleotide, and the sequences were A and T rich. In addition, the two ways of phylogenetic analysis show that the position of A. lappa and A. tomentosum is consistent within Asteraceae.

To investigate whether exogenous sucrose can protect cucumber from water stress, cucumber (Cucumis sativus L.) seedlings were pretreated with 90 mM sucrose or 90 mM mannitol for 1 d and then were dehydrated with 10 % (m/v) polyethylene glycol (PEG) 6000 for further 1 d. Dehydration inhibited plant growth and decreased osmotic potential and relative water content (RWC) in leaves. The pretreatment with 90 mM sucrose further reduced the osmotic potential but increased the RWC and alleviated the growth inhibition. Compared with the PEG treatment alone, the combination of sucrose + PEG increased the activities of superoxide dismutase, guaiacol peroxidase, glutathione reductase, dehydroascorbate reductase, monodehydroascorbate reductase, ascorbate peroxidase, and glutathione peroxidase, and elevated the content of endogenous sucrose, glucose, and fructose together with the activities of soluble acid invertase and neutral invertase. This was in accordance with the enhanced transcription of genes encoding copper/zinc superoxide dismutase, guaiacol peroxidase, and glutathione reductase. Furthermore, the sucrose pretreatment decreased the content of malondialdehyde and hydrogen peroxide and increased the content of ascorbate, reduced glutathione, and proline under the dehydration. Taken together, the pretreatment with 90 mM sucrose, but much less with mannitol, induced antioxidants, proline, and soluble sugars and thus reduced dehydration-caused damage to the cucumber seedlings.

Cellular behaviour is controlled by numerous processes, including intracellular signalling pathways that are triggered by the binding of ligands with cell surface receptors. Multivalent ligands have multiple copies of a recognition element that binds to receptors and influences downstream signals. Nanoparticle-ligand complexes may form multivalent structures to crosslink receptors with high avidity and specificity. After conjugation onto gold nanoparticles, galectin-1 (Au-Gal1) bound with higher affinity to Jurkat cells to promote CD45 clustering and inhibition of its phosphatase activity, resulting in enhancement of apoptosis via caspase-dependent pathways. Au-Gal1 injected intra-articularly into rats with collagen-induced arthritis (CIA) promoted apoptosis of CD4+ T cells and reduced pro-inflammatory cytokine levels in the ankle joints as well as ameliorated clinical symptoms of arthritis. These observed therapeutic effects indicate that the multivalent structure of nanoparticle-ligands can regulate the distribution of cell surface receptors and subsequent intracellular signalling, and this may provide new insights into nanoparticle applications.