Abstract
From the 16th to the 19th centuries, Western medicine emerged in China and was considered dangerous by Chinese residents. Relatedly, Chinese medical practitioners have attempted to use ...knowledge based on traditional Chinese medicine to explain the principles of Western medicine. From the 19th to 20th centuries, traditional Chinese medicine (TCM) was introduced to the United States, and American residents also described it as dangerous; they believed that TCM could only be accepted after scientific verification and explanation. This article uses the method of historical anthropology to explain these phenomena using boundaries as an analytical concept. This article finds that when foreign medicine crosses borders, it causes the disorganization of local classification systems. When a local classification system cannot provide a suitable location for foreign medicine, such medicine is easily regarded as dangerous by residents. The key to solving this problem is to use local classification systems to reinterpret foreign medicine. Reinterpreted by these local classification systems, foreign medicine can gain legitimacy within local societies. Based on this, the current article attempts to illustrate not only that science is a classification method but also that the boundary between science and nonscience is cultural in a sense, thereby undertaking corresponding cultural functions in daily life.
Regenerative medicine holds much promise in assisting patients to recover from injured or lost tissues and organs through organism reconstruction. Three-dimensional (3D) biomimetic models via various ...approaches can be used by pharmaceutical industry for controlled drug delivery. With proper biomaterials and engineering technologies, drugs can be released in a rate-manipulated manner towards targeted regions with spatial and temporal effects. Much of the success is a result of a combination of growth factors, stem cells, biomaterials, nanotechnologies, electrospinning and 3D printing techniques mimicking in vivo angiogenesis, histogenesis and tumorigenesis processes. This interdisciplinary field on biomimetic drug delivery and regenerative medicine has already opened up a new avenue for medical progress and reformation. This article presents a comprehensive review of the 3D biomimetic models in the pertinent fields of tissue and organ manufacturing, cell-material mutual interactions, bioactive agent carrier systems and anti-cancer drug delivery methods. Particularly, the potential trends and challenges of tissue and organ manufacturing are discussed from different perspectives.
The weakening effect of water in rocks has been extensively investigated over the past few decades. The degradation of the strength and stiffness of rocks can vary greatly with rock type. To ...investigate the water-weakening effect on the mechanical properties and failure modes of a Hydropower station's bedrock, static and cyclic triaxial compressive tests were carried out on dry, natural, and saturated tuffs (from the Badantoru Hydropower Station in Indonesia) under different confining pressures. Analysis of the failure modes, stress-strain curves, and brittleness index revealed that all of the samples exhibited typical brittle fracture behavior, i.e., a stress drop, volumetric dilation, and no compaction bands. The decreases in the peak stress, residual stress, and elastic modulus with increasing water content verify the water-weakening effect. The correlations between the water content and the confining pressure and other characteristic parameters calculated using the Pearson correlation coefficient indicate that the peak stress and elastic modulus are negatively correlated with the water content, and the peak stress, peak strain, and elastic modulus are positively correlated with the confining pressure. Compared with the Mohr-Coulomb criterion, the Hoek-Brown criterion can better describe the failure behavior of tuffs. Two damage variables, DE and Dε, were defined based on the hysteretic energy and residual strain. Both can characterize the damage evolution and failure mechanism, and DE can describe the stages of the damage evolution in more detail.
•All tuff samples present typical brittle fracture behavior and water-weakening effect.•Compared with saturated tuffs, dry ones can withstand more cyclic loads.•High confining pressure can inhibit the water-weakening effect on tuffs.•Damage variable based on hysteretic energy can better characterize the damage evolution of tuffs.
Nitrogen metabolism is an important physiological process that affects the survival and virulence of
.
's utilization of nitrogen in the environment and its adaptation to the harsh environment of ...acid and low oxygen in macrophages are closely related to nitrogen metabolism. In addition, the dormancy state and drug resistance of
are closely related to nitrogen metabolism. Although nitrogen metabolism is so important, limited research was performed on nitrogen metabolism as compared with carbon metabolism.
can use a variety of inorganic or organic nitrogen sources, including ammonium salts, nitrate, glutamine, asparagine, etc. In these metabolic pathways, some enzymes encoded by key genes, such as GlnA1, AnsP2, etc, play important regulatory roles in the pathogenesis of TB. Although various small molecule inhibitors and drugs have been developed for different nitrogen metabolism processes, however, long-term validation is needed before their practical application. Most importantly, with the emergence of multidrug-resistant strains, eradication, and control of
will still be very challenging.
As the proportion of renewable energy generation continues to increase, the participation of new energy stations with high-proportion energy storage in power system frequency regulation is of ...significant importance for stable and secure operation of the new power system. To address this issue, an energy storage control method based on quantum walks and model predictive control (MPC) has been proposed. First, historical frequency deviation signals and energy storage charge–discharge state signals are collected. Simulation data are generated through amplitude encoding and quantum walks, followed by quantum decoding. Subsequently, the decoded data are inputted into the MPC framework for real-time control, with parameters of the predictive model continuously adjusted through a feedback loop. Finally, a novel power system frequency regulation model with high-proportion new energy storage stations is constructed on the MATLAB/Simulink platform. Simulation verification is conducted with the proportional–integral–derivative (PID) and MPC methods as comparative approaches. Simulation results under step disturbances and random disturbances demonstrate that the proposed method exhibits stronger robustness and better control accuracy.
Objective:
Because infections caused by nontuberculous mycobacteria (NTM) are rapidly increasing globally, a need exists for developing novel antibiotics and discovering the mechanism of resistance. ...This research was aimed at understanding the mechanism of bedaquiline resistance in the model NTM species
Mycobacterium marinum
(
M. marinum
).
Methods:
The
Mycobacterium marinum
M strain was subjected to mutant selection with different concentrations of BDQ. After three rounds of evolution, 58 BDQ-resistant mutants were isolated and subjected to WGS. The results were confirmed through PCR and Sanger sequencing.
Results:
We identified seven genetic mutations among these mutants. The highest drug resistance (6–10× MIC) was associated with a mutation in AtpB, the primary biochemical target of BDQ in Mtb. Numerous mutations and insertions mapped to the gene
MMAR_1007
(46/58), which encodes the homolog of Rv0678 (MmpR) in Mtb. More than 93% of mutants (54/58) contained a single mutation (G563A) in
MMAR_4049
, which encodes the integral membrane protein YrbE3A-1.
Conclusion:
Both target-based and efflux-based actions contribute to BDQ resistance in
M. marinum.
Our findings may aid in developing novel potent anti-NTM (BDQ-based) drug regimens and diagnostic assays for the detection of BDQ-resistant
M. marinum
.
Drip irrigation can reduce water and fertilizer use; however, the frequency of topdressing required for drip irrigation for wheat in the Huang-Huai-Hai region is still unclear. Through two continuous ...wheat season field experiments, yield related traits under traditional surface irrigation (border irrigation) and three drip fertilization frequencies (DF2, DF3, DF4, that was, topdressing water and fertilizer twice, three or four times in the same way during the growth period) of three wheat cultivars (Jimai 22, Jimai 20, Shiluan 02-1) were studied. Increasing the frequency of drip irrigation fertilization could prolong the time of high-level photosynthesis, increase the dry matter distribution amount (DMDA) of stems and leaves, and add the weight of 1000 grains; it could increase the DMDA and nitrogen distribution amount (NDA) of the stems, leaves, and grains of Jimai 22, forming higher harvest index (HI) and nitrogen harvest index (NHI), but could reduce the DMDA of the grains of Jimai 20 and Shiluan 02-1, increasing NDA, reducing the harvest index but forming a higher nitrogen harvest index. The increase in drip irrigation fertilization frequency can improve protein content, increase grain number per spike, decrease spike number, improve the yield of medium gluten wheat, and improve nitrogen partial productivity and water use efficiency, while strong gluten wheat has a decrease in yield, nitrogen partial productivity, and water use efficiency. In summary, medium gluten wheat is more suitable for higher fertilization frequency in the Huang-Huai-Hai wheat region, while strong gluten wheat is the opposite.
How to release growth factors (GFs) scientifically to promote stem cell proliferation and differentiation is one of the most significant research focuses in the field of regenerative medicine. In a ...controlled release system, growth factors, extracellular matrices or biomaterial carriers, and sometimes stem cells together form a geometric entirety. Biomaterial carriers provide GFs with a support structure to be adhered, immobilized, encapsulated or/and protected. As a unity, the release rate and rhythm of GFs on cells are normally very delicate and precise. Up to now, the best strategy for clinical applications is the combination systems that encapsulate GFs in microspheres, particularly the nano- or micro-encapsulation techniques integrated GFs with biomaterial carriers. In this mini review, we summarize the current progress in GF delivery systems for regenerative medicine and provide an outlook on two main aspects: one is the classes of stem cells and GFs that have been used frequently in regenerative medicine, including their respective application conditions and functions; the other is the controlled GF release systems, in which various GFs are released orderly and continuously without diffusing simply and rapidly, including their respective opportunities and challenges.
Epoxy resin insulating materials are prone to charge accumulation under the high voltage and high temperature stress, which can distort the electric field distribution and eventually lead to ...insulation failure. Appropriately increasing the electrical conductivity of epoxy resin materials could effectively accelerate the dissipation of accumulated charges, may thus provide a potential method to improve the insulation strength. The conductivity of epoxy resin materials is closely related to their cross-linked molecular structure. In this work, based on the structural changes of cross-linked molecules, we explore the mechanisms by which terminal chlorine affects the energy level distribution and trap properties of cross-linked molecules. These influence mechanisms could be explained in terms of electron cloud offset and electron energies. According to quantum chemical calculation results, the changes in the charge transport process in cross-linked molecules are compared, and the volume resistivity and DC breakdown strength data of the epoxy resin materials are analyzed at different terminal chlorine contents. The results suggest that terminal chlorine alters the charge hopping barrier in the cross-linked molecules, potentially affecting the intramolecular charge transport process.
