18 research outputs found
From Beginner to Expert: Modeling Medical Knowledge into General LLMs
Recently, large language model (LLM) based artificial intelligence (AI)
systems have demonstrated remarkable capabilities in natural language
understanding and generation. However, these models face a significant
challenge when it comes to sensitive applications, such as reasoning over
medical knowledge and answering medical questions in a physician-like manner.
Prior studies attempted to overcome this challenge by increasing the model size
(>100B) to learn more general medical knowledge, while there is still room for
improvement in LLMs with smaller-scale model sizes (<100B). In this work, we
start from a pre-trained general LLM model (AntGLM-10B) and fine-tune it from a
medical beginner towards a medical expert (called AntGLM-Med-10B), which
leverages a 3-stage optimization procedure, i.e., general medical knowledge
injection, medical domain instruction tuning, and specific medical task
adaptation. Our contributions are threefold: (1) We specifically investigate
how to adapt a pre-trained general LLM in medical domain, especially for a
specific medical task. (2) We collect and construct large-scale medical
datasets for each stage of the optimization process. These datasets encompass
various data types and tasks, such as question-answering, medical reasoning,
multi-choice questions, and medical conversations. (3) Specifically for
multi-choice questions in the medical domain, we propose a novel
Verification-of-Choice approach for prompting engineering, which significantly
enhances the reasoning ability of LLMs. Remarkably, by combining the above
approaches, our AntGLM-Med-10B model can outperform the most of LLMs on
PubMedQA, including both general and medical LLMs, even when these LLMs have
larger model size.Comment: Developed by Ant Group for PubMedQA leaderboar
Plastic deformation regularity of tailor-welded tube hydroforming
13-19To reveal the deformation characteristics
and influence of dissimilar thickness on hydro-bugling of tailor-welded tube
(TWT), FEA, experiments and mechanics analysis are conducted. The effects of
length ratio, weld-seam movement and work-hardening on deformation
compatibility are analyzed. It indicates that the plastic deformation occurs
first at the middle zone of the thinner tube, and then extends to the thicker
tube crossing the weld-seam. The expansion occurring on the two parts with
dissimilar thickness is non-uniform, higher the length ratio and higher the
deformation compatibility. Stress-strain analysis reveals that though the whole
TWT suffers biaxial tensile stresses and the biaxial elongation occurs in the
thinner tube, axial compressive strain occurs in the thicker tube. It is
concluded that the mechanism for improving the deformation compatibility is to
induce the deformation in the thicker tube by enhancing the bulging pressure
needed for the thinner tube through changing the stress state of the thinner
tube and flowing stress. Weld-seam movement happens during tailor-welded tube
hydroforming, which induces uneven distribution of axial strain and thinning
ratio in the TWT
A comparative study on phosphate removal from water using <italic toggle="yes">Phragmites australis</italic> biochars loaded with different metal oxides
Metal oxide-loaded biochars are a promising material to remove phosphate from polluted water to ultra-low concentrations. To facilitate preparing the metal oxide-loaded biochar with the best phosphate adsorption performance, five biochars loaded with Al, Ca, Fe, La and Mg oxides, respectively (Al-BC, Ca-BC, Fe-BC, La-BC and Mg-BC) were produced using Phragmites australis pretreated with 0.1 mol AlCl3, CaCl2, FeCl3, LaCl3 and MgCl2, respectively, characterized, and phosphate adsorption kinetics and isotherms of the biochars were determined. The maximum phosphate adsorption capacities (Qm) of the biochars ranked as Al-BC (219.87 mg gā1) > Mg-BC (112.45 mg gā1) > Ca-BC (81.46 mg gā1) > Fe-BC (46.61 mg gā1) > La-BC (38.93 mg gā1). The time to reach the adsorption equilibrium ranked as La-BC (1 h) < Ca-BC (12 h) < Mg-BC (24 h) = Fe-BC (24 h) <Al-BC (greater than 72 h). Qm of Ca-BC, Fe-BC, La-BC and Mg-BC depend on the molar content of metals in the biochars. The small phosphate adsorption rate of Al-BC is due to the slow intra-particle diffusion of phosphate attributed to the undeveloped porosity and dispersed distribution of AlOOH crystals on the Al-BC surface. Mg-BC is suggested for phosphate removal from water considering adsorption rate and capacity. Al-BC is applicable when a long contact time is allowed, e.g. as a capping material to immobilize phosphate in lake sediments
Microstructure Characterization of Reversed Transformation in Cryogenically Rolled 22MnB5
Hot stamping is a well-known process to produce structural automotive parts with an excellent strength-to-weight ratio. However, this process is more expensive due to the lower energy efficiency and operating cost of the traditional roller-hearth furnace. Additionally, lower ductility and toughness are commonly recognized as the main disadvantages of the current hot stamped ultra-high-strength parts. Refinement of austenite grains could be a profitable way to improve the strength of hot stamped parts. In this work, the evolution of reversed transformation in asymmetrically cryogenically rolled samples was studied in order to control the austenite. Thermomechanical simulation and heat treatment in the salt bath were used to investigate the reversed transformation process, and the typical microstructures were characterized by transmission electron microscopy (TEM) and scanning electron microscopy (SEM). Compared with symmetric prerolling, ferrite recrystallization could be remarkably inhibited by asymmetric rolling at the liquid nitrogen temperature (LNT) during the reheating process. Additionally, the nucleation of the austenite inner grains can also be promoted and the dynamics of the reversed transformation accelerated by asymmetric prerolling. Such phenomena might be very useful to refine the parent austenite grains before press hardening and enhance the new hot stamping strategy by partial fast reheating
Synergistic antibacterial activity of physical-chemical multi-mechanism by TiO2 nanorod arrays for safe biofilm eradication on implant
Treatment of implant-associated infection is becoming more challenging, especially when bacterial biofilms form on the surface of the implants. Developing multi-mechanism antibacterial methods to combat bacterial biofilm infections by the synergistic effects are superior to those based on single modality due to avoiding the adverse effects arising from the latter. In this work, TiO2 nanorod arrays in combination with irradiation with 808 near-infrared (NIR) light are proven to eradicate single specie biofilms by combining photothermal therapy, photodynamic therapy, and physical killing of bacteria. The TiO2 nanorod arrays possess efficient photothermal conversion ability and produce a small amount of reactive oxygen species (ROS). Physiologically, the combined actions of hyperthermia, ROS, and puncturing by nanorods give rise to excellent antibacterial properties on titanium requiring irradiation for only 15Ā min as demonstrated by our experiments conducted in vitro and in vivo. More importantly, bone biofilm infection is successfully treated efficiently by the synergistic antibacterial effects and at the same time, the TiO2 nanorod arrays improve the new bone formation around implants. In this protocol, besides the biocompatible TiO2 nanorod arrays, an extra photosensitizer is not needed and no other ions would be released. Our findings reveal a rapid bacteria-killing method based on the multiple synergetic antibacterial modalities with high biosafety that can be implemented in vivo and obviate the need for a second operation. The concept and antibacterial system described here have large clinical potential in orthopedic and dental applications
Hot Deformation Behavior, Processing Maps and Microstructural Evolution of the Mg-2.5Nd-0.5Zn-0.5Zr Alloy
Isothermal hot compression experiments were conducted on Mg-2.5Nd-0.5Zn-0.5Zr alloy to investigate hot deformation behavior at the temperature range of 573ā773 K and the strain rate range of 0.001 sā1ā10 sā1 using a Gleeble-3500D thermomechanical simulator. The results showed that the rheological curve showed a typical work hardening stage, and there were three different stages: work hardening, transition and steady state. A strain compensation constitutive model was established to predict the flow stress of the Mg-2.5Nd-0.5Zn-0.5Zr alloy, and the results proved that it had high predictability. The main deformation mechanism of the Mg-2.5Nd-0.5Zn-0.5Zr alloy was dislocation climbing. The processing maps were established to distinguish the unstable region from the working region. The maps showed that the instability generally occurred at high strain rates and low temperatures, and the common forms of instability were cracking and flow localization. The optimum machining range of the alloy was determined to be 592ā773 K and 0.001ā0.217 sā1. With the increase in deformation temperature, the grain size of the alloy grew slowly at the 573ā673 K temperature range and rapidly at the 673ā773 K temperature range