Y. Zhao’s research while affiliated with First Affiliated Hospital of China Medical University and other places

Background Starting biologic treatment early in the course of inflammatory bowel disease (IBD) may associate with higher efficacy, especially in Crohn’s disease (CD). Methods A systematic review and individual-patient-data meta-analysis of all placebo-controlled trials of biologics approved for IBD at study inception (Oct 2015), using Vivli data-sharing platform. The primary outcome was the proportional biologic/placebo treatment effect on induction-of-remission in patients with short-duration (≤18months) versus long-duration disease (>18months) analyzed separately for CD and ulcerative colitis (UC). We used meta-regression to examine the impact of patients’ characteristics on the primary outcome. Study PROSPERO registration: CRD42018041961. Results We obtained data from five biologics drug manufacturers and included 25 trials, testing infliximab, adalimumab, certolizumab, golimumab, natalizumab or vedolizumab (6,168 CD, 3,227 UC patients). In CD, induction-of-remission rates were higher in pooled placebo and active arms’ patients with short-disease duration≤18 months (41.4%, 244/589) compared with disease-duration>18months (29.8%, 852/2857, meta-analytically estimated OR=1.33, 95%CI:1.09–1.64). The primary outcome, proportional biologic/placebo treatment effect on induction-of-remission, was not different in short-duration disease ≤18 months (n= 589, OR 1.47, 95%CI:1.01–2.15) compared with longer disease-duration (n=2857, OR 1.43, 95%CI:1.19–1.72). In UC trials, both the proportional biologic/placebo remission-induction effect and the pooled biologic-placebo effect were stable regardless of disease duration. Primary outcome results remained unchanged when tested using alternative temporal cut-offs and when modelled for individual-patients’ co-variates, including prior anti-TNFs exposure. In exploratory post-hoc analysis comparing patients with colonic-CD (L2) versus small-bowel L1 CD (and excluding ileo-colonic L3 disease) the OR for induction-of-remission in long-duration disease>18months compared with short-duration disease was 0.62 for small-bowel CD (95%CI: 0.42; 0.91) but was not significant in pooled colonic CD population (OR=0.94, 95%CI: 0.66; 1.34) Conclusion This Individual patient level meta-analysis of clinical trials of multiple biologics found there are higher rates of induction-of-remission in early CD for both biologics and placebo, resulting in a treatment-to-placebo effect ratio which is similar across different disease durations. No such relationships between disease-duration and outcomes is found in UC

Room-temperature brittleness and strain-softening during deformation of bulk metallic glasses, and limited processability of shape memory alloys have been stumbling blocks for their advanced functional structural applications. To solve the key scientific problems, a new shape memory bulk metallic glass based composite, through the approach using transformation-induced plasticity (TRIP) effect of shape memory alloys to enhance both ductility and work-hardening capability of metallic glasses, and superplasticity of bulk metallic glass in supercooled liquid region to realize near net forming, was developed in this work. And the Ti-Ni base bulk metallic glass composites (BMGCs) rods were prepared by the levitation suspend melting-water cooled Cu mold process. Microstructure, thermal behavior, mechanical properties and high temperature deformation behavior of the alloy were investigated. The results show that the as-cast alloy microstructure consists of amorphous matrix, undercooled austenite and thermally-induced martensite. Besides, the size of the crystal phase precipitated on the amorphous matrix in-creases from the surface to the inside. The alloy exhibits excellent comprehensive mechanical properties at room temperature. The yield strength, fracture strength and the plastic strain of alloy are up to 1286 MPa, 2256 MPa and 12.2%, respectively. Under compressive loading in the supercooled liquid region, the composite exhibits approximate Newtonian behavior at lower strain rate in higher deformation temperature, and the optimum deformation temperature is T>480℃ and the intersection part with supercooled liquid region (SLR). When the temperature is 560℃ and the strain rate is 5×10⁻⁴ s⁻¹, the stress sensitivity index m and the energy dissipation rate ψ are 0.81 and 0.895, respectively. Furthermore, the volume of activation is quantified to characterize the rheological behavior.

Due to the amorphous structure of amorphous alloys, amorphous alloys exhibit high strength, high hardness and poor processability at room temperature. However, amorphous alloys exhibit superplastic characteristics of low viscosity and high fluidity in the supercooled liquid region(SCLR), which provides a new way for plastic processing of amorphous alloys. In this paper, the characteristics of the thermoplastic micro-forming technology in SCLR of the amorphous alloy were reviewed. Compared with the traditional crystalline materials, the advantages of amorphous alloys as ideal micro-forming materials were summarized. In addition, the attractive application prospect of amorphous alloys in the field of micro-electromechanical systems (MEMS) was introduced and the research results of domestic and overseas in the field of thermoplastic micro-forming of amorphous alloys were listed. The applications of amorphous alloys in microelectronic systems, precision gratings, super-hydrophobic surfaces, bio-chips and micro fuel cells were summarized. At the same time, the problems in the development of micro-forming technology for amorphous alloys were pointed out and the importance of developing micro-forming technology for amorphous alloys was reaffirmed. © 2018, Chongqing Functional Materials Periodical Press Co. Ltd. All right reserved.

How to enhance room-temperature plasticity and toughness have been obstacles for advanced functional structural applications of bulk amorphous alloy. Understanding of the plastic deformation mechanism under loading at room temperature is a precondition for plasticity and toughness improvements. Formation and propagation of highly localized shear bands produce the plastic deformation of bulk amorphous alloy. And to increase the room temperature plasticity depends on how to make the uniform distribution of the shear band. A thorough and detailed research in the field have been done and obtained different methods for plasticity and toughness improvements, such as shot peening, high Poisson's ratio of amorphous alloy system design, as cast phase-separated amorphous alloy system with microstructural fluctuation, introduction of crystalline phase, and so on. In this paper, the research hot spot, the plastic toughness criterion, the method of finding the formation and expansion of the block amorphous alloys are reviewed from six aspects, that is, the second phase toughened amorphous matrix composites, Poisson's ratio criterion, size effect, surface modifications, preforming multiple shear bands improves preform plasticity, and thermal cycling induced rejuvenation, etc. The paper also points out that to obtain excellent tensile ductility and fracture toughness, is the research object and important development direction of different amorphous alloy systems, and promotes the application and industrialization of bulk amorphous alloy as a new type of functional structural material.

Microstructure and mechanical properties of Zr64+xCu26-xAl10 bulk amorphous alloys and composites were studied. Effect of overheated level on mechanical properties of bulk amorphous composites was also investigated. The relationship between microstructure and mechanical properties was discussed. The results showed that Zr60Cu30Al10 had good thermal stability and the best glass forming ability in the alloy system, of which ΔTx, Trg and γ were 69 K, 0.573 and 0.402, respectively. With the decrease of Cu content, the glass forming ability decreased. Nanocrystalline with different sizes precipitated on the amorphous matrix of Zr64Cu26Al10 alloy. And the presence of nanocrystals could effectively toughen the glass matrix, and hinder the atomic motion in the shear zone to narrow the shear band, thus strengthening the matrix. The fracture strength and plastic strain of Zr64Cu26Al10 alloy were 1610 MPa and 6.34%, respectively. When x=4, 8, 12, crystal phase CuZr2, ZrCu and Cu10Zr7 gradually precipitated in the alloys. And the mechanical properties of the composites depended on the combination of the brittle phases and the toughening phases. The increase of overheated level would promote the formation of amorphous and enhance the strength, thus improving the mechanical properties. © Editorial Office of Chinese Journal of Rare Metals. All right reserved.

Ti-Ni-based amorphous composite samples (Ti0.5Ni0.5)100-xCux with different Cu contents but the same diameter which has been prepared by the copper mold suction casting. The effect of the Cu contents (x=0, 10, 15, 20, 25, 30, 35, 40, at%) on the microstructures and mechanical properties of the amorphous composites was studied. Results show that both fracture strength and plastic strain of the alloy are very high when the copper content is x=20. Meanwhile the alloy exhibits the best comprehensive properties. As the x value increases, the glass forming ability of (Ti0.5Ni0.5)100-xCux alloy shows a waveform change from increasing to decreasing and then to increasing, but following an overall trend towards decreasing. The plasticity of Ti-Ni-based amorphous materials can be improved by adding Cu element in modest quantities (x≈25) to the Ti-Ni-based composites; however, adding more Cu (i.e., x>30) neither can improve the amorphous forming ability nor can enhance its strength. When x=15, the alloy has the highest breaking strength of 2440 MPa while gets the higher yield strength of 1471 MPa causing 17.15% plastic strain. The data are pretty high with respect to other amorphous systems or other alloy systems with memory of their shapes. When x=25, there is a certain increase in the alloy plastic strain with 21.35% plastic deformation. Copyright © 2017, Northwest Institute for Nonferrous Metal Research. Published by Elsevier BV. All rights reserved.

Ladder (Zr63.36/100Cu14.25/100Ni10.12/100Al12/100)100-xErx(x=0.5, 1, 1.5, 2, 2.5, 3) rods with diameters of 2, 4 and 6 mm were prepared by copper mold casting method. The effects of size on mechanical properties of Zr-based BMGs were studied by X-ray diffraction (XRD), universal testing machine and scanning electron microscope (SEM). The results show that when x=2 and 2.5, the specimens of 2 mm in diameter experienced a large compressive plastic deformation, which reached 24.59% and 24.93%, respectively, but the alloy specimen of 4 and 6 mm in diameter remained substantially unchanged in compressive plastic deformation. It can be concluded that the compressive plasticity of this amorphous alloy decreases as its size increases. In other words, the plasticity of amorphous alloy has size effect. Its elastic modulus, yield strength and fracture strength also decreases as its size increases, indicating that with the increase of the size of this amorphous alloy, its mechanical performance gradually decreases. © 2017, Chongqing Functional Materials Periodical Press Co. Ltd. All right reserved.

Background: Crohn's disease (CD) mainly affects young adults of reproductive age. Few studies have been conducted on their ovarian reserve status, and factors associated with impaired ovarian reserve remains unknown. This study aimed to investigate potential risk factors associated with low ovarian reserve as reflected by serum anti-Mullerian hormone (AMH) in young women of reproductive age with CD. Methods: This individual matched, case-control study was conducted in the First Affiliated Hospital of Sun Yat-sen University. Cases were 87 patients diagnosed with CD and controls were paired with no history of IBD, recruited in a 1:1 ratio, for age, height, weight and BMI index. Serum AMH levels were measured by ELISA. Results: The serum AMH level was significantly lower in CD patients than health control group (2.47±2.08ng/ml vs 4.12±2.31ng/ml, p<0.001), which remained comparable with the age younger than 25 years (4.41±1.52ng/ml vs 3.49±2.10ng/ml, p=0.06), but decreased in CD patients after 25 years at any age stage (p<0.05). Patients with active disease (p<0.05), stricturing type (B2) (p<0.05), perianal disease (p<0.05), ileocolonic (L3) involved disease (p<0.05) and receiving thalidomide therapy (p<0.05) showed a significantly lower serum AMH level. Multivariable logistic regression analysis showed that age more than 25 years old (OR: 9.33, 95% CI 1.85–47.05, p<0.05), active disease (OR: 24.2, 95% CI 5.56–104.75, p<0.05) and thalidomide use (OR: 19.6, 95% CI 2.99–118.6, p<0.05) were independent risk factors were associated with low ovarian reserve in CD patients. Conclusions: Age more than 25 years old, active disease and thalidomide use were independently associated with low ovarian reserve in young women of reproductive age with CD.

Tapered Cu50Zr42Al8 alloy with good glass-forming ability was fabricated by copper mould suction casting. Cubic AlCu2Zr and B2-ZrCu, thermal-induced martensitic B19'-ZrCu phases form on the glass matrix along the radial direction structure. Size effects on micro-mechanical properties and a unique crack healing behavior were studied. Micro-hardness of monolithic bulk metallic glass (BMG) displays "smaller is softer" trend, that is, the softer surface and the harder center. Whereas the lager size composites possess a softer center and a harder surface, due to the integrative action of the secondary phases. Amorphous matrix is toughened by TRIP (transition induced plasticity) effect of shape-memory phase as well as weakened and embrittled by AlCu2Zr crystal. After annealing, self-healing of Vickers indentation crack occurs as the thermoelastic transformation of shape-memory crystals. As loading, stress-induced martensites transform from B2 to B19', along with volume expansion. Annealed upon the reverse transformation temperature, B19' to B2 transform accompanied by a volume shrinkage, and a restoring force from the structure stress is set up to drive the crack closure. Copyright © 2017, Northwest Institute for Nonferrous Metal Research. Published by Elsevier BV. All rights reserved.

The influences of strain rates on mechanical properties and serrated flow behaviors of Zr67.76Cu11.94Ni8.30Al12 metallic glass composite have been investigated with statistical methods. The results demonstrate that both the plastic strain and the compressive strength decrease with the increasing of strain rates. Meanwhile, the serrated distribution of stress drop (Δσ) changes from monotonically decreasing into a peak-like shape, and the absolute frequency transits from a small interval to a large one. The serrated number of unit plastic strain (M) continuously declines. Moreover, the number of the shear bands decreases and the interaction among them significantly weakens. In the meantime, the extension transforms from multiple shear bands to a single shear band, resulting in the rapid decline in mechanical properties of the composite.