Physical organ models are the objects that replicate the patient-specific anatomy and have played important roles in modern medical diagnosis and disease treatment. 3D printing, as a powerful multi-function manufacturing technology, breaks the limitations of traditional methods and provides a great potential for manufacturing organ models. However, the clinical application of organ model is still in small scale, facing the challenges including high cost, poor mimicking performance and insufficient accuracy. In this review, the mainstream 3D printing technologies are introduced, and the existing manufacturing methods are divided into "directly printing" and "indirectly printing", with an emphasis on choosing suitable techniques and materials. This review also summarizes the ideas to address these challenges and focuses on three points: 1) what are the characteristics and requirements of organ models in different application scenarios, 2) how to choose the suitable 3D printing methods and materials according to different application categories, and 3) how to reduce the cost of organ models and make the process simple and convenient. Moreover, the state-of-the-art in organ models are summarized and the contribution of 3D printed organ models to various surgical procedures is highlighted. Finally, current limitations, evaluation criteria and future perspectives for this emerging area are discussed.

Highlights d Wild Prunus germplasm is collected from the high altitudes of the Himalayas d SINE retrotransposons expand in the genomes of three Tibetan Prunus species d UV response and phenylpropanoid metabolism associate with high-altitude adaptation d Specific SINE insertions change the expression of altituderelated genes

A series of Ni-based catalysts supported on different MgO supports were investigated for hydrogen production via steam reforming (SR) of acetic acid (HAc). Three types of NiO and MgO solid solutions were prepared by co-precipitation of Ni(NO 3 ) 2 and Mg(NO 3 ) 2 , impregnation of Ni(NO 3 ) 2 on MgO, and impregnation of Ni(NO 3 ) 2 on mesoporous MgO (denoted as MgO-m), respectively. The Ni-based catalysts were prepared by reducing these solid solutions at 650 °C in 10% H 2 /Ar. N 2 adsorption results showed that the Brunauer−Emmett−Teller (BET) surface area of NiO/MgO-m solid solution was 3.0 and 2.3 times that of NiO−MgO and NiO/MgO solid solutions, respectively. The Ni/MgO-m catalyst showed the best catalytic performance, and the H 2 yield can be enhanced by ∼160% by using the Ni/MgO-m catalyst. Ni/MgO-m kept its high activity up to 20 h of reaction. Thermogravimetry (TG) results indicated that no significant change was observed for the amount of carbon deposits on used Ni/MgO-m after 3 h on stream. Two kind of carbon species were observed on used Ni/MgO-m in the temperature-programmed oxidation (TPO) test.

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