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激光诱发化学气相淀积

微电子学与计算机 1988年第2期 30-36页

作者： Raj Solanki Cameron A.Moore george j.collins 孙建诚

本文回顾了薄膜的激光诱发淀积的进展.原则上,膜的光激活化学气相淀积依据于三大机理.施主分子光分解及随后的反应和凝聚;衬底局部被加热后,随之在这些位置上的热分解;以及在紧靠衬底附近所需物质的激光蒸发.这三种方法都已经用于淀积... 详细信息

本文回顾了薄膜的激光诱发淀积的进展.原则上,膜的光激活化学气相淀积依据于三大机理.施主分子光分解及随后的反应和凝聚;衬底局部被加热后,随之在这些位置上的热分解;以及在紧靠衬底附近所需物质的激光蒸发.这三种方法都已经用于淀积绝缘的、导电的和半导体的材料.讨论了大面积的和局部的淀积,重点在前者.激光诱发淀积的独特之处在于:工艺温度低、分解产物一定以及空间上有选择地淀积.介绍了在微电子器件制造中以前和将来的应用,考察了激光化学气相淀积在集成电路工艺中应用存在的问题和前景.

关键词：淀积 LCVD 光分解衬底施主分子分解反应基片激光诱发淀积速率激光

地球演化历史中氧逸度变化对壳幔循环启动、风化和超大陆循环的指示（英文）

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Science Bulletin 2024年第1期 97-102页

作者：王瑞邬绍宸 Roberto F.Weinberg William j.collins Peter A.Cawood State Key Laboratory of Geological Processes and Mineral Resources Institute of Earth Sciences China University of Geosciences Frontiers Science Center for Deep-time Digital Earth China University of Geosciences (Beijing) School of Earth Atmosphere and Environment Monash University The Institute for Geoscience Research Curtin University

We apply a zircon redox index to a global compilation of detrital zircons to track the variation of oxidation state, expressed as ΔFMQ, through Earth’s history. Those from I-type rocks, which comprise mantle and crustal igneous protoliths, including tonalite–trondhjemite–granodiorites(TTGs), generally have a high oxidation state(ΔFMQ > 0). In contrast, zircons from igneous rocks derived from supracrustal source rocks(S-type) are commonly reduced(ΔFMQ 0 over the last 3 Ga. Given that the redox state of magmas is independent of crustal thickness and silica variation, and elevated values are likely more closely related to tectonic setting, we suggest that the consistent average ΔFMQ > 0 from ca.3.5 Ga onwards relates to recycling of oceanic lithosphere back into the mantle in what eventually became established as subduction zones. The more reduced magmas associated with sedimentary sources, became established at 2.6 Ga, presumably in response to continental rocks rising above sealevel, and follow peaks of productivity associated with the supercontinent cycle.

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Development and characterization of 3D-printed electroconductive pHEMA-co-MAA NP-laden hydrogels for tissue engineering

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Bio-Design and Manufacturing 2024年第3期7卷 262-276页

作者： Sara De Nitto Aleksandra Serafin Alexandra Karadimou Achim Schmalenberger john j.EMulvihill Maurice N.collins DIBRIS Polytechnic Inter-School Section University of Genoa16126 GenoaItaly School of Engineering Bernal InstituteUniversity of LimerickLimerick V94 T9PXIreland School of Natural Sciences Department of Biological SciencesUniversity of LimerickLimerick V94 T9PXIreland Health Research Institute University of LimerickLimerick V94 T9PXIreland AMBER University of LimerickLimerick V94 T9PXIreland

Tissue engineering(TE)continues to be widely explored as a potential solution to meet critical clinical needs for diseased tissue replacement and tissue *** this study,we developed a poly(2-hydroxyethyl methacrylate-co-methacrylic acid)(pHEMA-co-MAA)based hydrogel loaded with newly synthesized conductive poly(3,4-ethylene-dioxythiophene)(PEDOT)and polypyrrole(PPy)nanoparticles(NPs),and subsequently processed these hydrogels into tissue engineered constructs via three-dimensional(3D)*** presence of the NPs was critical as they altered the rheological properties during ***,all samples exhibited suitable shear thinning properties,allowing for the development of an optimized processing window for 3D *** were 3D printed into pre-determined disk-shaped configurations of 2 and 10 mm in height and diameter,*** observed that the NPs disrupted the gel crosslinking efficiencies,leading to shorter degradation times and compressive mechanical properties ranging between 450 and 550 *** conductivity of the printed hydrogels increased along with the NP concentration to(5.10±0.37)×10^(−7)S/*** vitro studies with cortical astrocyte cell cultures demonstrated that exposure to the pHEMA-co-MAA NP hydrogels yielded high cellular viability and proliferation ***,hydrogel antimicrobial studies with staphylococcus epidermidis bacteria revealed that the developed hydrogels affected bacterial *** together,these materials show promise for various TE strategies.

关键词： Conductive nanoparticles Hydroxyethyl methacrylate(HEMA) Ultraviolet(UV)polymerization 3D printing

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Examining the“revisability”benefit of hip resurfacing arthroplasty

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World journal of Orthopedics 2024年第6期15卷 554-559页

作者： jose george Adam j Taylor Thomas P Schmalzried Department of Orthopedics Harbor UCLA Medical CenterTorranceCA 90509United States

BACKGROUND Hip resurfacing arthroplasty(HRA)is an alternative to total hip arthroplasty(THA)that is typically reserved for young active patients because it preserves ***,the benefits of HRA only hold true if conversion THA after failed HRA provides acceptable *** To compare patient reported outcomes for conversion THA after HRA failure to primary *** A retrospective review of 36 patients(37 hips)that underwent conversion THA for failed HRA between October 2006 and May 2019 by a single surgeon was *** reported outcomes[modified Harris Hip Score(mHHS),University of California Los Angeles(UCLA)activity score]were obtained via an email-based responder-anonymous *** were compared to normative data of a primary THA cohort with similar *** analysis was performed comparing outcomes of conversion THA for adverse local tissue reaction(ALTR)vs all other causes for *** The study group had a lower mHHS than the control group(81.7±13.8 vs 90.2±11.6,P<0.01);however,both groups had similar UCLA activity levels(7.5±2.3 vs 7.2±1.6,P=0.51).Patients that underwent conversion for non-ATLR causes had similar mHHS(85.2±11.5 vs 90.2±11.6,P=0.11)and higher UCLA activity levels(8.5±1.8 vs 7.2±1.6,P<0.01)compared to the control *** that underwent conversion for ATLR had worse mHHS(77.1±14.5 vs 90.2±11.6,P<0.01)and UCLA activity levels(6.1±2.3 vs 7.2±1.6,P=0.05)when compared to the control *** Patient outcomes equivalent to primary THA can be achieved following HRA conversion to ***,inferior outcomes were demonstrated for ALTR-related HRA *** selection and perhaps further studies examining alternative HRA bearing surfaces should be considered.

关键词： Total hip arthroplasty Hip resurfacing arthroplasty Conversion total hip arthroplasty Adverse local tissue reaction Patient reported outcome measures

Genetics of Gallstone Disease and Their Clinical Significance: A Narrative Review

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journal of Clinical and Translational Hepatology 2024年第3期12卷 316-326页

作者： Christopher j.Costa Minh Thu T.Nguyen Haleh Vaziri george Y.Wu Department of Medicine University of Connecticut Health CenterFarmingtonCTUSA Division of Gastroenterology and Hepatology University of Connecticut Health CenterFarmingtonCTUSA

Gallstone(GS)disease is common and arises from a combination of genetic and environmental *** genetic abnormalities specifically leading to cholesterol GSs are rare,there are clinically significant gene variants associated with cholesterol *** contrast,most bilirubin GSs can be attributed to genetic *** pathogenesis of cholesterol and bilirubin GSs differs *** GSs are notably influenced by genetic variants within the ABC protein superfamily,including ABCG8,ABCG5,ABCB4,and ABCB11,as well as genes from the apolipoprotein family such as ApoB100 and ApoE(especially the E3/E3 and E3/E4 variants),and members of the MUC ***,bilirubin GSs are associated with genetic variants in highly expressed hepatic genes,notably UGT1A1,ABCC2(MRP2),ABCC3(MRP3),CFTR,and MUC,alongside genetic defects linked to hemolytic anemias and conditions impacting *** genetic cases constitute a small portion of GS disease,recognizing genetic predisposition is essential for proper diagnosis,treatment,and genetic counseling.

关键词： Gallstones Cholelithiasis ATP-binding cassette transporters ABCG8 protein Human UDP-glucuronosyltransferase A1

Adaptive Random Effects/Coefficients Modeling

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Open journal of Statistics 2024年第2期14卷 179-206页

作者： george j. Knafl School of Nursing University of North Carolina at Chapel Hill Chapel Hill USA

Adaptive fractional polynomial modeling of general correlated outcomes is formulated to address nonlinearity in means, variances/dispersions, and correlations. Means and variances/dispersions are modeled using generalized linear models in fixed effects/coefficients. Correlations are modeled using random effects/coefficients. Nonlinearity is addressed using power transforms of primary (untransformed) predictors. Parameter estimation is based on extended linear mixed modeling generalizing both generalized estimating equations and linear mixed modeling. Models are evaluated using likelihood cross-validation (LCV) scores and are generated adaptively using a heuristic search controlled by LCV scores. Cases covered include linear, Poisson, logistic, exponential, and discrete regression of correlated continuous, count/rate, dichotomous, positive continuous, and discrete numeric outcomes treated as normally, Poisson, Bernoulli, exponentially, and discrete numerically distributed, respectively. Example analyses are also generated for these five cases to compare adaptive random effects/coefficients modeling of correlated outcomes to previously developed adaptive modeling based on directly specified covariance structures. Adaptive random effects/coefficients modeling substantially outperforms direct covariance modeling in the linear, exponential, and discrete regression example analyses. It generates equivalent results in the logistic regression example analyses and it is substantially outperformed in the Poisson regression case. Random effects/coefficients modeling of correlated outcomes can provide substantial improvements in model selection compared to directly specified covariance modeling. However, directly specified covariance modeling can generate competitive or substantially better results in some cases while usually requiring less computation time.

关键词： Adaptive Regression Correlated Outcomes Extended Linear Mixed Modeling Fractional Polynomials Likelihood Cross-Validation Random Effects/Coefficients

An Analysis of Specific Categories of Birth Defects and Developmental Disabilities for Children of Participants of the Air Force Health Study

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Open journal of Epidemiology 2024年第2期14卷 312-330页

作者： george j. Knafl School of Nursing University of North Carolina at Chapel Hill Chapel Hill NC USA

Background: The Air Force Health Study collected reproductive outcomes for live-born children of male Air Force veterans of the Vietnam War. Methods: Dioxin values for participants were obtained from blood samples. Analyses were conducted of occurrence of 16 specific categories of birth defects and developmental disabilities. Children were categorized as conceived before and after the start of participants’ Vietnam War service. Children conceived before the start of Vietnam War service were treated as being conceived when their fathers had unquantifiable dioxin values. Children conceived after the start of Vietnam War service for participants with missing dioxin values were excluded from primary analyses, but were used to assess the impact of their exclusion on conclusions. Correlation between values for specific categories for multiple children fathered by the same participant was accounted for. The dose-response relationship was treated as a step function increasing for dioxin values larger than adaptively identified individual thresholds changing with the specific category. Results: For 15 of 16 specific categories, the probability of occurrence increased substantially for a sufficiently high dioxin level above identified thresholds. Exclusion of children due to missing dioxin likely did not affect these results. Conclusions: Results supported the conclusion of substantial adverse effects on a wide variety of specific categories of birth defects and developmental disabilities due to sufficiently high exposures to dioxin, a toxic contaminant of Agent Orange used for herbicide spraying in the Vietnam War. Results may hold more generally, but might also have been affected by a variety of limitations.

关键词： Agent Orange Air Force Health Study Birth Defects Developmental Disabilities Dioxin Dose-Response Relationship Vietnam War

Thermochemical co-conversion of biomass-plastic waste to biochar:a review

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Green Chemical Engineering 2024年第1期5卷 31-49页

作者： Adewale george Adeniyi Kingsley O.Iwuozor Ebuka Chizitere Emenike Oluwaseun j.Ajala Samuel Ogunniyi Kabir B.Muritala Department of Chemical Engineering Faculty of Engineering and TechnologyUniversity of IlorinIlorinP.M.B.1515Nigeria Department of Chemical Engineering Landmark UniversityOmu-AranKwara StateP.M.B.1001Nigeria Department of Pure and Industrial Chemistry Nnamdi Azikiwe UniversityAwkaP.M.B.5025Nigeria Department of Chemistry Federal University of TechnologyBosso CampusMinnaNiger StateP.M.B.65Nigeria

Biomass and plastics are two of the most common municipal solid wastes globally that have continuously placed a burden on the *** is therefore important that they are properly *** coconversion offers a valuable opportunity to recycle biomass and plastics simultaneously into biochar,which reduces the time and cost of recycling them individually while producing a material with a wide range of *** study is a review of published literature that discusses the thermochemical co-processing of biomass and plastic wastes into *** was observed that co-pyrolysis and co-hydrothermal carbonization are the most commonly utilized technologies for this *** characteristics of different biomass and plastics that have been thermochemically converted into biochar were *** properties of the resulting biochar are affected by the feedstock composition,pre-treatment and blending ratio,the reactor’s configuration,reaction temperature,and the presence of a *** studies found that treating the feedstocks separately resulted in a lower yield of biochar than processing them *** biochar created by this procedure has been used as a soil additive and as an adsorbent for water *** perspectives and suggestions,such as the necessity for some technical advancement,biochar’s economic benefits,improved government participation,and raised social awareness,were also *** factors have the potential to propel this field of study to great horizons.

关键词： Biomass Co-pyrolysis Plastic Thermochemical process Valorization

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Using Inductance as a Tuning Parameter for RF Meta-atoms

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Nano-Micro Letters 2012年第2期4卷 103-109页

作者： Derrick Langley Ronald A.Coutu Peter j.collins Air Force Institute of Technology Wright-Patterson Air Force Base

The resonant frequency of metamaterials structured with split ring resonator(SRR) meta-atoms is determined primarily through the capacitance and inductance of the individual meta-atoms. Two designs that vary inductance incrementally were modeled, simulated, fabricated, and tested to investigate the role inductance plays in metamaterial designs. The designs consisted of strategically adding sections to the SRR to increase the inductance, but in a manner that minimized capacitance variations. Each design showed a shift in resonant frequency that was proportional to the length of the added section. As the length of each section was increased, the resonant frequency shifted from 2.78 GHz to 2.18 GHz.

关键词： Inductance Meta-atom Metamaterial Split Ring Resonator Radio Frequency Resonance

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