Bronchoalveolar lavage fluid assessment facilitates precision medicine for lung cancer

Lung cancer is the most common and fatal malignant disease worldwide and has the highest mortality rate among tumor-related causes of death.Early diagnosis and precision medicine can significantly improve the survival rate and prognosis of lung cancer patients.At present,the clinical diagnosis of lung cancer is challenging due to a lack of effective non-invasive detection methods and biomarkers,and treatment is primarily hindered by drug resistance and high tumor heterogeneity.Liquid biopsy is a method for detecting circulating biomarkers in the blood and other body fluids containing genetic information from primary tumor tissues.Bronchoalveolar lavage fluid(BALF)is a potential liquid biopsy medium that is rich in a variety of bioactive substances and cell components.BALF contains information on the key characteristics of tumors,including the tumor subtype,gene mutation type,and tumor environment,thus BALF may be used as a diagnostic supplement to lung biopsy.In this review,the current research on BALF in the diagnosis,treatment,and prognosis of lung cancer is summarized.The advantages and disadvantages of different components of BALF,including cells,cell-free DNA,extracellular vesicles,and micro RNA are introduced.In particular,the great potential of extracellular vesicles in precision diagnosis and detection of drug-resistant for lung cancer is highlighted.In addition,the performance of liquid biopsies with different body fluid sources in lung cancer detection are compared to facilitate more selective studies involving BALF,thereby promoting the application of BALF for precision medicine in lung cancer patients in the future.

Impacts of high temperature,relative air humidity,and vapor pressure deficit on the seed set of contrasting maize genotypes during flowering

Heat stress is a major constraint to current and future maize production at the global scale.Male and female reproductive organs both play major roles in increasing seed set under heat stress at flowering,but their relative contributions to seed set are unclear.In this study,a 2-year field experiment including three sowing dates in each year and 20 inbred lines was conducted.Seed set,kernel number per ear,and grain yield were all reduced by more than 80%in the third sowing dates compared to the first sowing dates.Pollen viability,silk emergence ratio,and anthesis-silking interval were the key determinants of seed set under heat stress;and their correlation coefficients were 0.89^(***),0.65^(***),and-0.72^(***),respectively.Vapor pressure deficit(VPD)and relative air humidity(RH)both had significant correlations with pollen viability and the silk emergence ratio.High RH can alleviate the impacts of heat on maize seed set by maintaining high pollen viability and a high silk emergence ratio.Under a warming climate from 2020 to 2050,VPD will decrease due to the increased RH.Based on their pollen viability and silk emergence ratios,the 20 genotypes fell into four different groups.The group with high pollen viability and a high silk emergence ratio performed better under heat stress,and their performance can be further improved by combining the improved flowering pattern traits.

互联网+新形态下“化工原理”创新教学模式的构筑与实践

信息时代的到来,为教育开辟了更加丰富的资源和途径,同时也为教与学带来了机遇和挑战。本文基于成果导向(OBE)的教学理念,针对化工原理课程中存在的教学痛点问题,从工程认证背景下持续改进的要求出发,充分利用互联网信息技术,结合生活与国家低碳环保发展需求,构筑案例分析、理论教学、项目驱动、思政引领、网络辅助“五位一体”的教学模式,充分体现“知识目标、能力目标和素养目标”的相互融合,满足新工科背景下应用型人才培养的需求。

Fibroblast Adhesion and Proliferation on a New β Type Ti-39Nb-13Ta-4.6Zr Alloy for Biomedical Application

Cell attachment and spreading on Ti-based alloy surfaces is a major parameter in implant technology. Ti-39Nb-13Ta-4.6Zr alloy is a new β type Ti alloy developed for biomedical application. This alloy has low modulus and high strength, which indicates that it can be used for medical purposes such as surgical implants. To evaluate the biocompatibility and effects of the surface morphology of Ti-39Nb-13Ta-4.6Zr on the cellular behaviour, the adhesion and proliferation of rat gingival fibroblasts were studied with substrates having different surface roughness and the results were also compared with commercial pure titanium and Ti-6Al-4V. The results indicate that fibroblast shows similar adhesion and proliferation on the smooth surfaces of commercial pure titanium （Cp Ti）, Ti-39Nb-13Ta-4.6Zr, and Ti-6Al-4V, suggesting that Ti-39Nb-13Ta-4.6Zr has similar biocompatibility to Cp Ti and Ti-6Al-4V. The fibroblast adhesion and spreading was lower on rough surfaces of Cp Ti, Ti-39Nb-13Ta-4.6Zr and Ti-6Al-4V than on smooth ones. Surface roughness appeared to be a dominant factor that determines the fibroblast adhesion and proliferation.

“三因一选”模式--新时代大学化学实验教学改革探索

人才发展是强国利器。对综合型人才培养而言,本科化学实验教学意义重大。本文针对大学化学实验课程提出"三因一选"的教学模式,即因"材"施教、因地制宜、因势利导和自选课题实验。"三因一选"模式旨在将本科各专业的特色与具体实验内容结合起来,增强学生的主观能动性,强化学生的创造性思维和实践创新能力。

金色梦想,一触即发——化学专业校外实践教学基地建设与思考

高等教育要适应世界潮流和时代变化,本科教育须进一步提高实践教学的比重,加强理论教学与实践教学相结合,完善协同育人机制。结合学科发展和企业发展需求,中山大学化学学院与金发科技股份有限公司(简称金发科技)共同建设大学生实践教学基地。本文以中山大学-金发科技本科实践教学基地为例,探讨大学生校外实践基地建设过程中遇到的问题以及实践基地的建设内容与成果体会。

Preparation of Flax Residue Activated Carbon by KOH Method and Its Electrode Performance

In this study, activated carbon was prepared by the potassium hydroxide activation method with flax residues as raw materials. High-quality activated carbon was prepared by single factor and orthogonal experiments. Iodine adsorption and methylene blue adsorption were used as performance indicators. As prepared activated carbon was characterized by XRD, XPS and SEM. The results showed that the optimized electrode material was prepared under an impregnation ratio of 1:2, activation temperature of 800°C and activation time of 100 min. The yield of activated carbon was 49.48%, the iodine value was 1667.13 mg/g and the methylene blue value was 429 mg/g. The specific surface area measured by the automatic porosity analyzer is 1221 m2/g, and the mass-specific capacitance is 215.7 F/g under current density of 0.1 A/g.

聚碳酸酯型形状记忆聚氨酯的合成与表征

以碳化二亚胺改性MDI(MM103)、1,4-丁二醇(BDO)和聚碳酸1,6-己二醇酯二醇(PCDL)为原料,采用一步熔融法合成了系列聚碳酸酯型形状记忆聚氨酯弹性体(PCPU)。通过红外测试、差示扫描量热测试、硬度测试、拉伸强度测试、吸水率测试和形状记忆性能测试研究了硬段含量对材料性能的影响。结果表明,随着硬段含量的增加,PCPU的硬度逐渐增大,吸水率、拉伸强度和断裂伸长率均是先增加后减小;硬段含量为15%～20%时,PCPU的形状固定率和形状恢复率最高。

Practical Structural Design Approach of Multiconfiguration Planar Single‑Loop Metamorphic Mechanism with a Single Actuator

As a type of multiconfiguration mechanism that can operate in an under-actuated state,metamorphic mechanisms were proposed more than two decades ago and attracted significant interest.Studies on structural synthesis of metamorphic mechanisms tend to focus more on metamorphic techniques and the structural synthesis of source mechanisms for metamorphic mechanisms.By designing different constraint architectures of metamorphic joints,multistructures can be obtained from the same source metamorphic mechanism.To determine the constraint architectures of metamorphic joints and their different assembly combinations,a kinematic status matrix and a corresponding constraint status matrix are constructed based on the metamorphic cyclogram of a source mechanism.According to the equivalent resistance gradient model and the constraint status matrix,an equivalent resistance matrix for the metamorphic joints is proposed.A structural synthesis matrix of the metamorphic mechanism is then obtained from the equivalent resistance matrix by deducing the constraint form vectors of the metamorphic joints.Furthermore,a kinematic diagram synthesis of the source metamorphic mechanism of a planar single-loop metamorphic mechanism is proposed,which is based on only the 14 one-or zero-degrees-of-freedom linkage groups.The entire structural design method of a metamorphic mechanism is based on the structural synthesis matrix and is presented as a systematic process.Finally,the proposed structural design approach is illustrated by two examples to verify its feasibility and practicality.This study provides an effective method for designing a practical multi-mobility and multiconfiguration planar single-loop metamorphic mechanism with a single actuator.

Polyoxymethylene dimethyl ethers synthesis from methanol and formaldehyde solution over one-pot synthesized spherical mesoporous sulfated zirconia

The synthesis of polyoxymethylene dimethyl ethers as an ideal diesel fuel additive is the current hot topic of modern petrochemical industry for their expedient properties in mitigating air pollutants emission during combustion.In this work,a series of spherical sulfated zirconia catalysts were prepared by a one-pot hydrothermal method assisted with surfactant cetyltrimethylammonium bromide(CTAB).The prepared sulfated zirconia catalysts were used to catalyze PODEn synthesis from methanol and formaldehyde solution.Various characterization(XRD,BET,SEM,TGA,NH_(3)-TPD,FTIR,and Py-IR)were employed to elaborate the structure–activity relationship of the studied catalytic system.The results demonstrated that S/Zr molar ratio in precursor solution played an effective role on catalyst morphology and acidic properties,where the weak Brønsted acid sites and strong Lewis acid sites were favorable to the conversion of methanol and formation of long-chain PODEn,respectively.The reaction parameters such as catalyst amount,molar ratio of FA/MeOH,reaction time,temperature and pressure were optimized.The speculated reaction pathway for PODEn synthesis was proposed based on the synergy of Brønsted and Lewis acid sites,which suggested that Brønsted and Lewis acid sites might be advantageous to the activation of polyoxymethylene hemiformals[CH_(3)(OCH_(2))_(n)OH]and methylene glycol(HOCH_(2)OH),respectively.

Contrasting vertical distribution between prokaryotes and fungi in different water masses on the Ninety-East Ridge, Southern Indian Ocean

Although the microbial diversity of the Indian Ocean has been extensively investigated,little is known about the community composition of microbes in the Southern Indian Ocean.In the present study,we divided 60 water column samples on the Ninety-East Ridge(NER)into fi ve water masses according to the temperature-salinity curves.We presented,for the fi rst time,a full description of the microbial biodiversity on NER through high-throughput amplicon sequencing approach,including bacteria,archaea,and fungi.We found that bacteria exhibited higher richness and diversity than archaea and fungi across the water masses on NER.More importantly,each water mass on NER featured distinct prokaryotic microbial communities,as indicated by the results of non-metric multidimensional scaling.In contrast,fungi were eurybathic across the water masses.Redundancy analysis results demonstrated that environmental factors might play a pivotal role in the formation and stability of prokaryotic communities in each water mass,especially that of archaea.In addition,indicator species might be used as fi ngerprints to identify corresponding water masses on NER.These results provide new insights into the vertical distribution,structure,and diversity of microorganisms on NER from the perspective of water mass.

Effect of Elastic Modulus on Biomechanical Properties of Lumbar Interbody Fusion Cage

This work focuses on the influence of elastic modulus on biomechanical properties of lumbar interbody fusion cages by selecting two titanium alloys with different elastic modulus. They were made by a new β type alloy with chemical composition of Ti-24Nb-4Zr-7.6Sn having low Young＇s modulus -50 GPa and by a conventional biomedical alloy Ti-6Al-4V having Young＇s modulus -110 GPa. The results showed that the designed cages with low modulus （LMC） and high modulus （HMC） can keep identical compression load -9.8 kN and endure fatigue cycles higher than 5× 10^6 without functional or mechanical failure under 2.0 kN axial compression. The anti-subsidence ability of both group cages were examined by axial compression of thoracic spine specimens （T9-T10） dissected freshly from the calf with averaged age of 6 months. The results showed that the LMC has better anti-subsidence ability than the HMC （p〈0.05）. The above results suggest that the cage with low elastic modulus has great potential for clinical applications.

Genetic Analysis of Segregation Distortion of Molecular Markers in Maize RIL Population

A RIL population was used in this study, which was derived from a cross between a temperate maize germplasm inbred line B31-1 and a tropical maize germplasm inbred lines Huangzao 4. A genetic linkage map was constructed comprising of 153 polymorphic markers. Among the 153 polymorphic markers, 82 markers showed the significantly segregation distortion（P〈0.05）, favoring either the marker alleles of female parent 1331-1（62.50%） or male parent Huangzao 4（37.50%）. Segregation distortion marker distribution along the present molecular maps of maize was far from uniform, with clusters of tightly linked loci and single marker. Nine segregation distortion regions were detected on 10 chromosomes, indicating that possible causes for segregation deviation of molecular markers are genetic selection.

A systematic literature review of the tension between the GDPR and public blockchain systems

Blockchain technology has been rapidly growing since Bitcoin was invented in 2008.The most common type of blockchain system,public(permissionless)blockchain system,has some unique features that lead to a tension with the European Union’s General Data Protection Regulation(GDPR)and other similar data protection laws.In this paper,we report the results of a systematic literature review(SLR)on 114 research papers discussing and/or addressing such a tension.To the best of our knowledge,our SLR is the most comprehensive review of this tension,leading to a more in-depth and broader analysis of related research work on this important topic.Our results revealed three main types of issues:(i)difficulties in exercising data subjects’rights such as the‘right to be forgotten’(RTBF)due to the immutable nature of public blockchains;(ii)difficulties in identifying roles and responsibilities in the public blockchain data processing ecosystem(particularly on the identification of data controllers and data processors);and(iii)ambiguities regarding the application of the relevant law(s)due to the distributed nature of blockchains.Our work also led to a better understanding of solutions for improving the GDPR compliance of public blockchain systems.It can help inform not only blockchain researchers and developers but also policymakers and law markers to consider how to reconcile the tension between public blockchain systems and data protection laws(the GDPR and beyond).

Influence of Component Size on the Corrosion Behavior of Ti6Al4V Alloy Fabricated by Electron Beam Powder Bed Fusion

The electrochemical behavior of Ti-6Al-4V with 1 mm and 16 mm thickness prepared by electron beam powder bed fusion(EB-PBF)was investigated in phosphate buffered saline.Electrochemical results showed that EB-PBF Ti-6Al-4V with a larger component size was more resistant to corrosion compared to the smaller component,because of less acicularαʹphase content and moreβphase content.As a non-equilibrium phase in the“high-energy state”,αʹphase has a greater susceptibility to corrode and reduces the corrosion resistance of the material,whileβphase improves corrosion resistance of titanium alloys.The results show that the phase composition has a more significant effect on the corrosion performance than the grain size.

Biofunctional magnesium coated Ti6Al4V scaffold enhances osteogenesis and angiogenesis in vitro and in vivo for orthopedic application

The insufficient osteogenesis and osseointegration of porous titanium based scaffold limit its further application.Early angiogenesis is important for scaffold survival.It is necessary to develop a multifunctional surface on titanium scaffold with both osteogenic and angiogenic properties.In this study,a biofunctional magnesium coating is deposited on porous Ti6Al4V scaffold.For osseointegration and osteogenesis analysis,in vitro studies reveal that magnesium-coated Ti6Al4V co-culture with MC3T3-E1 cells can improve cell proliferation,adhesion,extracellular matrix(ECM)mineralization and ALP activity compared with bare Ti6Al4V cocultivation.Additionally,MC3T3-E1 cells cultured with magnesium-coated Ti6Al4V show significantly higher osteogenesisrelated genes expression.In vivo studies including fluorochrome labeling,micro-computerized tomography and histological examination of magnesium-coated Ti6Al4V scaffold reveal that new bone regeneration is significantly increased in rabbits after implantation.For angiogenesis studies,magnesium-coated Ti6Al4V improve HUVECs proliferation,adhesion,tube formation,wound-healing and Transwell abilities.HUVECs cultured with magnesium-coated Ti6Al4V display significantly higher angiogenesis-related genes(HIF-1αand VEGF)expression.Microangiography analysis reveal that magnesium-coated Ti6Al4V scaffold can significantly enhance the blood vessel formation.This study enlarges the application scope of magnesium and provides an optional choice to the conventional porous Ti6Al4V scaffold with enhanced osteogenesis and angiogenesis for further orthopedic applications.

Fabrication of open-cellular(porous) titanium alloy implants: osseointegration, vascularization and preliminary human trials

In this study we describe the fabrication of a variety of open-cellular titanium alloy（Ti-6 Al-4 V） implants,both reticular mesh and foam structures, using electron beam melting（EBM）. These structures allow for the elimination of stress shielding by adjusting the porosity（or density） to produce an elastic modulus（or stiffness） to match that of both soft（trabecular） and hard（cortical） bone, as well as allowing for bone cell ingrowth, increased cell density, and all-matrix interactions; the latter involving the interplay between bone morphogenetic protein（BMP-2） and osteoblast functions. The early formation and characterization of elementary vascular structures in an aqueous hydrogel matrix are illustrated.Preliminary results for both animal（sheep） and human trials for a number of EBM-fabricated, and often patient-specific Tialloy implants are also presented and summarized. The results, while preliminary, support the concept and development of successful, porous, engineered ＂living＂ implants.

Effect of fluoride on the corrosion behavior of nanostructured Ti-24Nb-4Zr-8Sn alloy in acidulated artificial saliva

The surface of titanium dental implants is highly susceptible to aggressive fluoride ions in the oral environment. Nanotechnology has proven an effective approach to improve the stability and corrosion resistance of titanium by applying a passive film. In this study, we investigated the effects of fluoride on the corrosion behavior of nanostructured（NS） Ti-24 Nb-4 Zr-8 Sn（Ti2448） alloy in acidulated artificial saliva（AAS）at 37 ℃, and then conducted comparisons with its coarse grained（CG） counterpart. Electrochemical techniques, such as potentiodynamic polarization and electrochemical impedance spectroscopy（EIS）, as well as surface analysis including X-ray photoelectron spectroscopy（XPS） with argon ion sputtering, and scanning electronic microscopy（SEM） were employed to evaluate the effects of fluoride on sensitivity to pitting and the tolerance of Ti2448 to fluoride in AAS solution. The results demonstrate that corrosion current density increased with F-concentration. In all respects, the NS Ti2448 alloy presented corrosion resistance superior to that of its coarse grained（CG） counterpart at low F-concentrations（0.1%）.Furthermore, a high content of F-（1%） was shown to promote the active dissolution of both alloys by increasing the rate of corrosion. Following immersion in the fluoridated AAS solution for 60 days, a tissuefriendly compound, Ca3（PO4）2, was detected on the surface of the NS when F-= 0.01% and Na2 TiF6 was identified as the main component in the corrosion products of the CG as well as NS Ti2448 alloys when F-= 1%. High concentrations of F-produced pitting corrosion on the CG alloy, whereas NS Ti2448 alloy presented general corrosion in the form of lamellar separation under the same conditions. These findings demonstrate the superior corrosion resistance of the NS Ti2448 alloy as well as lower pitting sensitivity and higher tolerance to fluoride due mainly to grain refinement.

Carbon dots confined in 3D polymer network: Producing robust room temperature phosphorescence with tunable lifetimes

Room temperature phosphorescence(RTP) is important in both organic electronics and encryption. Despite rapid advances, a universal approach to robust and tunable RTP materials based on amorphous polymers remains a formidable challenge. Here, we present a strategy that uses three-dimensional(3 D)confinement of carbon dots in a polymer network to achieve ultra-long lifetime phosphorescence. The RTP of the as-obtained materials was not quenched in different polar organic solvents and the lifetime of the RTP was easily tuned by adjusting the amount of crosslinking or varying the drying temperature of the 3 D molecular network. As a demonstration of potential application, as-obtained RTP materials were successfully used to prepare RTP fibres for flexible textiles. As well as bringing to light a fundamental principle for the construction of polymer materials with RTP, we have endowed traditional carbon dots and polymers with fresh features that will expand potential applications.

Weak fatigue notch sensitivity in a biomedical titanium alloy exhibiting nonlinear elasticity

It is well known that metallic materials exhibit worse fatigue damage tolerance as they behave stronger in strength and softer in modulus. This raises concern on the long term safety of the recently developed biomechanical compatible titanium alloys with high strength and low modulus. Here we demonstrate via a model alloy, Ti-24 Nb-4 Zr-8 Sn in weight percent, that this group of multifunctional titanium alloys possessing nonlinear elastic deformation behavior is tolerant in fatigue notch damage. The results reveal that the alloy has a high strength-to-modulus（σ/E） ratio reaching2% but its fatigue notch sensitivity（q） is low, which decreases linearly from 0.45 to 0.25 as stress concentration factor increases from 2 to 4. This exceeds significantly the typical relationship between σ/E and q of other metallic materials exhibiting linear elasticity. Furthermore, fatigue damage is characterized by an extremely deflected mountain-shape fracture surface, resulting in much longer and more tortuous crack growth path as compared to these linear elastic materials. The above phenomena can be explained by the nonlinear elasticity and its induced stress relief at the notch root in an adaptive manner of higher stress stronger relief. This finding provides a new strategy to balance high strength and good damage tolerance property of metallic materials.