Journals
2025 EN
Duggar William N. · Wang Dongxu · Vergalasova Irina
+2 more
Abstract This work of fiction depicts a scenario in which a faculty member felt they were criticized unfairly and inappropriately for honesty on a faculty survey, which reflected poorly on administration. The faculty member was left struggling with how to respond to conflicting feelings and perception of misaligned goals and mission. Simultaneously, the department chair felt they were blindsided by issues that could have been addressed without the embarrassment of a poor survey. The intended use of this case, through group discussion, self‐study, or role‐play, is to encourage readers to discuss the situation at hand, inspire professionalism and leadership thinking, and allow the practice of conflict management. Facilitator's notes are available upon request to the MPLA Cases Subcommittee. This case study falls under the scope of and is supported by the Medical Physics Leadership Academy (MPLA), a committee in the American Association of Physicists in Medicine (AAPM).
Journals
2025 EN
Lim Seng Boh · Busse Nathan · Clements Jessica
+6 more
Abstract The American Association of Physicists in Medicine (AAPM) is a nonprofit professional society whose mission is “Advancing medicine through excellence in the science, education and professional practice of medical physics.” The AAPM has roughly 10,000 members and is the principal organization of medical physicists in the United States. The AAPM will periodically define new practice guidelines for medical physics practice to help advance the science of medical physics and to improve the quality of service to patients throughout the United States. Existing medical physics practice guidelines will be reviewed for the purpose of revision or renewal, as appropriate, on their fifth anniversary or sooner. Each medical physics practice guideline (MPPG) represents a policy statement by the AAPM, has undergone a thorough consensus process in which it has been subjected to extensive review, and requires the approval of the Professional Council. The medical physics practice guidelines recognize that the safe and effective use of diagnostic and therapeutic radiology requires specific training, skills, and techniques, as described in each document. Reproduction or modification of the published practice guidelines and technical standards by those entities not providing these services is not authorized. This report is an update of MPPG10.a, published in 2018, and provides the current minimum guidelines for the scope of practice for clinical medical physics as it has evolved to meet emerging needs and changes in practice. The following terms are used in the AAPM practice guidelines: Must and Must Not: Used to indicate that adherence to the recommendation is considered necessary to conform to this practice guideline. While must is the term to be used in the guidelines, if an entity that adopts the guideline has shall as the preferred term, the AAPM considers that must and shall have the same meaning. Should and Should Not: Used to indicate a prudent practice to which exceptions may occasionally be made in appropriate circumstances.
Journals
2025 EN
Georgantzinos Stelios K. · Papadopoulou Eleni · Kostopoulos Grigorios
+6 more
Additive manufacturing (AM) is revolutionizing space exploration and manufacturing by addressing unique challenges in weight reduction, material optimization, and on‐demand production. This review examines the current advances and future directions of AM for on‐Earth and in‐space applications. The study highlights the role of AM in producing lightweight, high‐performance components for satellites, rockets, and space habitats, leveraging technologies such as powder bed fusion, directed energy deposition, binder jetting, sheet lamination, and material extrusion. Key applications include the development of propulsion systems, structural components, and thermal management devices optimized for the harsh conditions of space. In‐space manufacturing is explored as a pivotal innovation, enabling the on‐demand production of tools, components, and infrastructure in microgravity environments, reducing launch costs and enhancing mission scalability. Challenges such as material defects, anisotropic properties, and residual stresses are discussed alongside strategies for mitigation, including real‐time monitoring and advanced post‐processing techniques. The review also emphasizes the ethical, regulatory, and sustainability considerations of AM for space exploration, addressing issues of resource utilization and environmental impact. Furthermore, it uniquely integrates advancements in artificial intelligence‐driven process control, in situ resource utilization, and sustainability aspects of AM for space missions.
Journals
2025 EN
Wang Gaopeng · Ni Haochen · Li Yifan
+7 more
Abstract Zwitterionic hydrogels have attracted intensive attentions for their exceptional hydration and anti‐fouling properties, while the exploration for rational structural designs to achieve multi‐function and superior anti‐freezing capability remains an ongoing mission. Herein, a new multi‐functional zwitterionic monomer (ACHPES) is designed and developed from which novel zwitterionic hydrogels are fabricated. The pyridinium‐sulfonate zwitterionic motif endows the hydrogel with discoloration in both visible light and fluorescence in response to pH stimulus, enabling unique multi‐channel information encryption and highly sensitive Cu 2+ detection with a detection threshold of 0.64 ppm. The design of carbamate group fulfils hydrogel high bonding capacity with water, leading to superior anti‐freezing capability. As such, the hydrogels exhibit an extremely low water freezing point of −47.3 °C and a high breaking elongation of ≈500% at −20 °C. The outstanding anti‐freezing capability enables hydrogel sensors and electrolytes an excellent operational performance at freezing temperatures. This innovative design strategy offers a new avenue for functionalization and application of zwitterionic hydrogels at icy temperature.
Journals
2025 EN
Chen Yujie · Fang Yan · Fu Xiaoqian
+15 more
Abstract Studying crystal defects is essential for understanding a material's origin, evolution, and behavior. Lunar materials can exhibit defects from space weathering including high‐energy ion implantations, which rarely happens on Earth. Investigating the variation in defects’ structure along the direction of implantation and its impact on lunar materials’ transformation is vital, but unfortunately, this remains unclear. Using multi‐scale, 3D characterization of lunar olivine from Chang'e‐5 mission, it is found that solar flare tracks, common lunar defects induced by implantation, have a “near‐linear” structure. These tracks show varied shuffling of oxygen and silicon atoms and vacancies along the traces. Intriguingly, the in situ electron microscopy heating experiments, detected for the first time that the evolution of solar flare tracks leads to the generation of iron nanoparticles and the release of oxygen upon heating. This reaction is rarely observed on Earth and unreported on the Moon before, which produces resources that can be harnessed for future human exploration and the establishment of lunar habitats.
Journals
2025 EN
Kim YoungKyeong · Lim Ik Jae · Lim Hongjin
+15 more
Abstract Despite significant technological advancements in space exploration, human space travel and colonization remain limited by the health risks associated with space radiation. Boron nitride nanotubes (BNNTs) have been proposed as an advanced material for space applications due to their high specific strength and efficient radiation shielding capabilities. However, the practical implementation of BNNTs has been slow, primarily due to technological challenges in fabricating structural materials incorporating BNNTs. In this study, a method is presented for fabricating high‐density BNNT films that are mechanically robust, exhibit high thermal conductivity, and effectively attenuate space radiation. The key advancement enabling high‐density BNNT films is the successful preparation of BNNT liquid crystals (LCs), achieved through the strategic use of a commercial dodecylbenzenesulfonic acid surfactant. This surfactant ensures exceptional BNNT stability in aqueous dispersion, even at concentrations exceeding the LC phase transition threshold. Simulations, estimating the equivalent radiation dose to the human body in space, indicate that a high‐density BNNT film with a surface density of 50 g cm − 2 reduces the total dose equivalent rate by 56% compared to zero shielding. This enhancement would allow astronauts to extend their mission duration on the lunar surface by a factor of two.
Journals
2025 EN
Ringel Benjamin M. · Semeraro Federico · Ferguson Joseph C.
+12 more
Abstract The oxidation of carbon fibers at high temperatures is the primary degradation process in the thermal protection system of many hypersonic flight vehicles. Predicting the rate and the extent of oxidation is critical to ensure a safe and effective design. An oversized thermal protection system adds unnecessary mass, while an under‐designed one risks system failure and mission loss. Resolving high‐temperature material degradation due to oxidation has been a long‐standing challenge in designing for re‐entry flight environments. Using time‐resolved in situ X‐ray microtomography, the oxidation of carbon fibers at high temperatures is directly imaged, resolving the two limiting degradation regimes: diffusion‐ and reaction‐limited. The ability to resolve material degradation in time at the sub‐micron scale sheds light on the ablation phenomenon and enables predictions of material constitutive properties evolving in time, with profound implications on the ability to model the aerothermal response of heat shield materials in hostile environments.
Journals
2025 EN
Fan Yurong · Chen Hao · Liu Xiaochuan
+4 more
Abstract Effective thermal control is critical for the safe operation of spacecraft in the harsh environment of outer space. Radiative cooling (RC), an advanced passive thermal management technology, enables spontaneous heat dissipation via infrared radiation into the ultracold cosmic background. It offers an energy‐efficient solution for maintaining temperature stability without power input. While RC materials have demonstrated promising potential in space applications, a systematic review focusing specifically on their performance and adaptability in space environments remains lacking. To fill this gap, this review first clarifies the fundamental and material‐requirement differences between terrestrial and space‐based RC. Next, it focuses on the space environmental effects on RC materials and their protection strategies, including extreme temperature fluctuations, space dust deposition, vacuum ultraviolet (VUV) radiation, and atomic oxygen (AO) erosion. Finally, key challenges and future research directions are discussed to guide the development of next‐generation RC materials for integrated spacecraft thermal control. This work provides valuable insights into advancing RC technologies, with implications for improving energy efficiency, extending mission lifespans, and enhancing system reliability in future space exploration.
Journals
2025 EN
Mao Chuanbin
60th Anniversary of The Chinese University of Hong Kong The Chinese University of Hong Kong (CUHK), one of Hong Kong's premier institutions of higher learning, was founded in 1963 with the mission of bridging Chinese and Western academic traditions. CUHK emerged from the combination of three colleges: Chung Chi College, United College, and New Asia College. Over the six decades, it has become a picturesque comprehensive research university with an international reputation for its excellence in teaching, research, and community engagement.
Journals
2025 EN
Houriet Caroline · Claassen Evelien · Mascolo Chiara
+10 more
Abstract Fused Filament Fabrication is a promising manufacturing technology for the circularity of space missions. Potential scenarios include in‐orbit applications to maximize mission life and to support long‐term exploration missions with in situ manufacturing and recycling. However, its adoption is restricted by the availability of engineering polymers displaying mechanical performance combined with resistance to space conditions. Here, a thermotropic Liquid Crystal Polymer (LCP) is reported as a candidate material with extrusion 3D printing. To expand its scope of applicability to structural parts for space applications, four different exposure conditions are studied: thermal cycling under vacuum, atomic oxygen, UV, and electron irradiations. While 1 MeV‐electron irradiation leads to a green coloration due to annealable color centers, the mechanical performance is only slightly decreased in dynamic mode. It is also found that increased printing temperature improves transverse strength and resistance to thermal cycling with the trade‐off of tensile stiffness and strength. Samples exposed to thermal cycling and the highest irradiation dose at lower printing temperatures still display a Young's modulus of 30 GPa and 503 MPa of tensile strength which is exceptionally high for a 3D‐printed polymer. For the types of exposure studied, overall, the results indicate that LCP 3D‐printed parts are well suited for space applications.