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Mesenchymal stem cell-based TRAIL delivery inhibits the metastatic state of clinical therapy-resistant progressive neuroblastoma

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World Journal of Pediatrics 2024年第3期20卷 287-293页

作者： Dinesh Babu Somasundaram Andrew Maher Sheeja Aravindan Zhongxin Yu brian MBesch Natarajan Aravindan Department of Radiation Oncology University of Oklahoma Health Sciences CenterOklahoma CityOKUSA Stephenson Cancer Center Oklahoma CityOKUSA Department of Pathology University of Oklahoma Health Sciences CenterOklahoma CityOKUSA Radiation Biology Laboratory University of Oklahoma Health Sciences CenterBSEB 302F941 Stanton L.Young BoulevardOklahoma CityOK 73104USA

Progressive neuroblastomas(pNBs)that defy current intensive multimodal clinical therapy(IMCT)are a significant contributor to overall childhood cancer deaths[l].Neuroblastomas(NBs)that survive first-line IMCT actively evolve to acquire genetic and molecular rearrangements and display unparalleled plasticity and evolution,which causes frequent relapses in a rapidly accelerating timeline[2-4].

关键词： neuroblastoma clinical evolve

Partial Volume Correction in SPECT Using Anatomical Information and Iterative fBP

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Tsinghua Science and Technology 2010年第1期15卷 50-55页

作者： Kjell Erlandsson brian f Hutton The Institute of Nuclear Medicine University College LondonLondonNW12BUUnited Kingdom

The ability to correctly quantify activity concentration with single photon emission computed tomography （SPECT） is limited by its spatial resolution. Blurring of data between adjacent structures, which is known as partial volume effects, can be compensated for by utilizing high resolution structural information from other imaging modalities such as CT or MRI. Previously developed partial volume correction （PVC） methods normally assume a spatially invariant point spread function. In SPECT this is not a good approximation, since the resolution varies with the distance from the collimator. A new method, p-PVC, was developed in this paper, which takes into account the distance dependent blurring. The method operates in projection space and is combined with filtered back-projection （fBP） reconstruction. Results from simulations show that similar quantitative results could be obtained with p-PVC＋fBP as with OSEM with resolution recovery, although with better structural definition and an order of magnitude faster.

关键词： partial volume effect (PVE) partial volume correction (PVC) SPECT

Rapidly Estimating Natural Gas Compressibility factor

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Journal of Natural Gas Chemistry 2007年第4期16卷 349-353页

作者： Alireza Bahadori Saeid Mokhatab brian f.Towler Department of Chemical Engineering Curtin University of Technology GPO Box 1987PerthWA 6845Australia Process Technology Department Tehran Raymand Consulting Engineers TehranIran Chemical and Petroleum Engineering Department University of Wyoming Laramie.WYUSA

Natural gases containing sour components exhibit different gas compressibility factor （Z） behavior than do sweet gases. Therefore, a new accurate method should be developed to account for these differences. Several methods are available today for calculating the Z-factor from an equation of state. However, these equations are more complex than the foregoing correlations, involving a large number of parameters, which require more complicated and longer computations. The aim of this study is to develop a simplified calculation method for a rapid estimating Z-factor for sour natural gases containing as much as 90% total acid gas. In this article, two new correlations are first presented for calculating the pseudo- critical pressure and temperature of the gas mixture as a function of the gas specific gravity. Then, a simple correlation on the basis of the standard gas compressibility factor chart is introduced for a quick estimation of sweet gases＇ compressibility factor as a function of reduced pressure and temperature. finally, a new corrective term related to the mole fractions of carbon dioxide and hydrogen sulfide is developed.

关键词： natural gas compressibility factor sour gas critical pressure critical temperature

On the homogenization of metal matrix composites using strain gradient plasticity

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Acta Mechanica Sinica 2014年第2期30卷 175-190页

作者： Reza Azizi Christian f.Niordson brian Nyvang Legarth Department of Mechanical Engineering Solid Mechanics Technical University of Denmark

The homogenized response of metal matrix composites（MMC） is studied using strain gradient *** material model employed is a rate independent formulation of energetic strain gradient plasticity at the micro scale and conventional rate independent plasticity at the macro scale. free energy inside the micro structure is included due to the elastic strains and plastic strain gradients. A unit cell containing a circular elastic fiber is analyzed under macroscopic simple shear in addition to transverse and longitudinal loading. The analyses are carried out under generalized plane strain condition. Micro-macro homogenization is performed observing the Hill-Mandel energy condition,and overall loading is considered such that the homogenized higher order terms vanish. The results highlight the intrinsic size-effects as well as the effect of fiber volume fraction on the overall response curves, plastic strain distributions and homogenized yield surfaces under different loading conditions. It is concluded that composites with smaller reinforcement size have larger initial yield surfaces and furthermore,they exhibit more kinematic hardening.

关键词： Metal matrix composite(MMC) Strain gradient plasticity Homogenization Yield surface

Transcription control engineering and applications in synthetic biology

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Synthetic and Systems Biotechnology 2017年第3期2卷 176-191页

作者： Michael D.Engstrom brian f.Pfleger Genetics-Biotechnology Center University of Wisconsin-Madison School of Medicine and Public HealthUSA Department of Chemical and Biological Engineering University of Wisconsin-Madison College of EngineeringUSA Microbiology Doctoral Training Program University of Wisconsin-MadisonUSA

In synthetic biology,researchers assemble biological components in new ways to produce systems with practical *** of these practical applications is control of the flow of genetic information(from nucleic acid to protein),*** *** is critical for optimizing protein(and therefore activity)levels and the subsequent levels of metabolites and other cellular *** central dogma of molecular biology posits that information flow commences with transcription,and accordingly,regulatory tools targeting transcription have received the most attention in synthetic *** this mini-review,we highlight many past successes and summarize the lessons learned in developing tools for controlling *** particular,we focus on engineering studies where promoters and transcription terminators(cis-factors)were directly engineered and/or isolated from DNA *** also review several well-characterized transcription regulators(trans-factors),giving examples of how cis-and trans-acting factors have been combined to create digital and analogue switches for regulating transcription in response to various ***,we provide examples of how engineered transcription control systems have been used in metabolic engineering and more complicated genetic *** most of our mini-review focuses on the well-characterized bacterium Escherichia coli,we also provide several examples of the use of transcription control engineering in non-model *** approaches have been applied outside the bacterial kingdom indicating that the lessons learned from bacterial studies may be generalized for other organisms.

关键词： Promoter Transcription Synthetic biology Bacteria Termination Metabolic engineering

Subaqueous early eruptive phase of the late Aptian Rajmahal volcanism,India:Evidence from volcaniclastic rocks,bentonite,black shales,and oolite

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Geoscience frontiers 2017年第4期8卷 809-822页

作者： Naresh C.Ghose Nilanjan Chatterjee brian f.Windley G/608 Raheja ResidencyKoramangala Department of Earth Atmospheric and Planetary SciencesMassachusetts Institute of Technology Department of Geology The University of Leicester

The late Aptian（118-115 Ma） continental flood basalts of the Rajmahal Volcanic Province（RVP） are part of the Kerguelen Large Igneous Province,and constitute the uppermost part of the Gondwana Supergroup on the eastern Indian shield *** lower one-third of the Rajmahal volcanic succession contains thin layers of plant fossil-rich inter-trappean sedimentary rocks with pyroclasts,bentonite,grey and black shale/mudstone and oolite,whereas the upper two-thirds consist of sub-aerial fine-grained aphyric basalts with no inter-trappean *** the eastern margin and the north-central sector of the RVP,the volcanics in the lower part include rhyolites and dacites overlain by enstatite-bearing basalts and *** pyroclastic rocks are largely felsic in composition,and comprise ignimbrite as well as coarse-grained tuff with lithic clasts,and tuff breccia with bombs,lapilli and ash that indicate explosive eruption of viscous rhyolitic *** rhyolites/dacites（〉68 wt.%） are separated from the andesites（〈 60 wt.%） by a gap in silica content indicating their formation through upper crustal anatexis with only heat supplied by the basaltic *** the other hand,partially melted siltstone xenoliths in enstatite-bearing basalts suggest that the enstatite-andesites originated through mixing of the upper crust with basaltic magma,crystallizing orthopyroxene at a pressure-temperature of ~3 kb/1150℃.In contrast,the northwestern sector of the RVP is devoid of felsic-intermediate rocks,and the volcaniclastic rocks are predominantly mafic（basaltic） in ***,the presence of fine-grained tuffs,tuff breccia containing sideromelane shards and quenched texture,welded tuff breccia,peperite,shale/mudstone and oolite substantiates a subaqueous *** on these observations,we conclude that the early phase of Rajmahal volcanism occurred under predominantly subaqueous *** presence of grey and black shale/mudstone in the lower one-third of

关键词： Rajmahal basalt Andesite Rhyolite Pyroclast Black shale Oolite

Sex-biased autophagy as a potential mechanism mediating sex differences in ischemic stroke outcome

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Neural Regeneration Research 2023年第1期18卷 31-37页

作者： brian Noh Louise D.McCullough Jose f.Moruno-Manchon Department of Neurology McGovern Medical School at the University of Texas Health Science Center at HoustonHoustonTXUSA

Stroke is the second leading cause of death and a major cause of disability worldwide,and biological sex is an important determining factor in stroke incidence and *** childhood through adulthood,men have a higher incidence of stroke compared with *** research has confirmed the beneficial effects of estrogen in experimental ischemic stroke but genetic factors such as the X-chromosome complement can also play an important role in determining sex differences in *** is a self-degrading cellular process orchestrated by multiple core proteins,which leads to the engulfment of cytoplasmic material and degradation of cargo after autophagy vesicles fuse with lysosomes or *** levels and the activity of components of these signaling pathways and of autophagy-related proteins can be altered during ischemic *** stroke activates autophagy,however,whether inhibiting autophagy after stroke is beneficial in the brain is still under a *** is a potential mechanism that may contribute to differences in stroke progression between the ***,the effects of manipulating autophagy may also differ between the *** that regulate autophagy in a sex-dependent manner in ischemic stroke remain *** this review,we summarize clinical and pre-clinical evidence for sex differences in *** briefly introduce the autophagy process and summarize the effects of gonadal hormones in autophagy in the brain and discuss X-linked genes that could potentially regulate brain ***,we review pre-clinical studies that address the mechanisms that could mediate sex differences in brain autophagy after stroke.

关键词： autophagy brain estrogen gonadal hormones neurodegeneration neuron stroke X-chromosome

Geological Evidence for the Operation of Plate Tectonics throughout the Archean:Records from Archean Paleo-Plate Boundaries

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Journal of Earth Science 2018年第6期29卷 1291-1303页

作者： Timothy M.Kusky brian f.Windley Ali Polat State Key Laboratory for Geological Processes and Mineral Resources China University of Geosciences Center for Global Tectonics School of Earth SciencesChina University of Geosciences Department of Geology University of Leicester Department of Earth and Environmental Sciences University of Windsor

Plate tectonics describes the horizontal motion of rigid lithospheric plates away from midoceanic ridges and parallel to transforms, towards deep-sea trenches, where the oceanic lithosphere is subducted into the mantle. This process is the surface expression of modern-day heat loss from Earth. One of the biggest questions in Geosciences today is ＂when did plate tectonics begin on Earth＂ with a wide range of theories based on an equally diverse set of constraints from geology, geochemistry, numerical modeling, or pure speculation. In this contribution, we turn the coin over and ask ＂when was the last appearance in the geological record for which there is proof that plate tectonics did not operate on the planet as it does today＂. We apply the laws of uniformitarianism to the rock record to ask how far back in time is the geologic record consistent with presently-operating kinematics of plate motion, before which some other mechanisms of planetary heat loss may have been in operation. Some have suggested that evidence shows that there was no plate tectonics before 800 Ma ago, others sometime before 1.8–2.7 Ga, or before 2.7 Ga. Still others recognize evidence for plate tectonics as early as 3.0 Ga, 3.3–3.5 Ga, the age of the oldest rocks, or in the Hadean before 4.3 Ga. A key undiscussed question is： why is there such a diversity of opinion about the age at which plate tectonics can be shown to not have operated, and what criteria are the different research groups using to define plate tectonics, and to recognize evidence of plate tectonics in very old rocks？ Here, we present and evaluate data from the rock record, constrained by relevant geochemical-isotopic data, and conclude that the evidence shows indubitably that plate tectonics has been operating at least since the formation of the oldest rocks, albeit with some differences in processes, compositions, and products in earlier times of higher heat generation and mantle temperature, weaker oceanic lithosphere, hotte

关键词： Archean tectonics ophiolite OPS(oceanic plate stratigraphy) orogeny

Growth factors for therapeutic angiogenesis in hypercholesterolemic erectile dysfunction

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Asian Journal of Andrology 2008年第1期10卷 23-27页

作者： Donghua Xie brian H. Annex Craig f. Donatucci Division of Cardiovascular Medicine and Department of Medicine Duke University Medical Center Durham NC 27710 USA Division of Cardiology and Department of Medicine Duke University Medical Center Durham NC 27710 USA Division of Urology Department of Surgery Duke University Medical Center Durham NC 27710 USA

The past decade has seen an explosion of new information on the physiology of penile erection, and pathophysiology of erectile dysfunction （ED）. Hypercholesterolemia is a chronic condition that can lead to degeneration in the vasculature bed and can result in ED if the penile vasculature is involved. Angiogenesis is the growth of new blood vessels from preexisting vasculature. Therapeutic angiogenesis seeks to harness the mechanisms of vascular growth to treat disorders of inadequate tissue perfusion, such as coronary artery disease and ED. There have been tremendous changes in the field of therapeutic angiogenesis over the past decade, and there is much promise for the future. Initial preclinical work with cytokine growth factor delivery resulted in a great deal of enthusiasm for the treatment of ischemic heart and/or peripheral vascular disease, though clinical studies have not achieved similar success. With an increased understanding of the complex mechanisms involved in angiogenesis, novel therapies which target multiple different angiogenic pathways are also being developed and tested. The penis is a convenient tissue target for gene therapy because of its external location and accessibility, the ubiquity of endothelial lined spaces, and low level of blood flow, especially in the flaccid state. Therapeutic angiogenesis is an exciting field that continues to evolve. This review will focus on the development of growth factors for hypercholesterolemic ED, the use of various growth factors for ED therapy, their routes of delivery, and the results in animal studies.

关键词： erectile dysfunction hypercholesterolemia angiogenic growth factors nitric oxide synthase