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Acta mechanica Sinica 2007年第5期23卷 477-483页

作者： Gaiping Zhao Jie Wu Shixiong Xu m. W. collins Quan Long Carola S. Konig Yuping Jiang Jian Wang A. R. Padhani Department of mechanics and Engineering Science Fudan University Shanghai 200433 China Brunel Institute for Bioengineering School of Engineering and Design Brunel University Uxbridge Middlesex UK Department of Neurology Huashan Hospital Fudan University Shanghai 200040 China Paul Strickland Scanner Centre Mount Vernon Hospital Rickmansworth Road Northwood Middlesex HA6 2RN UK

A coupled intravascular-transvascular-interstitial fluid flow model is developed to study the distributions of blood flow and interstitial fluid pressure in solid tumor microcirculation based on a tumor-induced microvascular network. This is generated from a 2D nine-point discrete mathematical model of tumor angiogenesis and contains two parent vessels. Blood flow through the microvascular network and interstitial fluid flow in tumor tissues are performed by the extended Poiseuille＇s law and Darcy＇s law, respectively, transvascular flow is described by Starling＇s law; effects of the vascular permeability and the interstitial hydraulic conductivity are also considered. The simulation results predict the heterogeneous blood supply, interstitial hypertension and low convection on the inside of the tumor, which are consistent with physiological observed facts. These results may provide beneficial information for anti-angiogenesis treatment of tumor and further clinical research.

关键词： Solid tumor pressure-Angiogenesis Blood flow - Interstitial Numerical simulation

GD2+ cancer stem cells in triple-negative breast cancer:mechanisms of resistance to breast cancer therapies

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Cancer Drug Resistance 2022年第3期5卷 721-726页

作者： Khoa Nguyen Emily mcConnell Orielle Edwards Bridgette m.collins-Burow matthew E.Burow Department of medicine Tulane University School of MedicineNew OrleansLA 70112USA

Research has led to the development of tailored treatment options for different cancers in different *** some treatments being able to provide remarkable responses,nearly all current treatments encounter the same issue:***,we discuss our experiences with how breast cancers resist *** focus of our discussion revolves around the cancer stem cell subpopulation and their mechanisms for resistance.

关键词： Drug resistance breast cancer therapy triple-negative breast cancer cancer stem cells

Earth’s tectonic and plate boundary evolution over 1.8 billion years

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Geoscience Frontiers 2024年第6期15卷 429-453页

作者： Xianzhi Cao Alan S.collins Sergei Pisarevsky Nicolas Flament Sanzhong Li Derrick Hasterok R.Dietmar müller Frontiers Science Center for Deep Ocean multispheres and Earth System Key Lab of Submarine Geosciences and Prospecting TechniquesMOE and College of Marine GeosciencesOcean University of ChinaQingdao 266100China Tectonics and Earth Systems&mineral Exploration Cooperative Research Centre School of PhysicsChemistry and Earth SciencesThe University of AdelaideAdelaideSA 5005Australia Earth Dynamics Research Group School of Earth and Planetary SciencesCurtin UniversityWA 6845Australia Environmental Futures School of EarthAtmospheric and Life SciencesUniversity of WollongongNorthfields AvenueNSW 2522Australia EarthByte Group School of GeosciencesThe University of SydneyNSW 2006Australia

Understanding the intricate relationships between the solid Earth and its surface systems in deep time necessitates comprehensive full-plate tectonic reconstructions that include evolving plate boundaries and oceanic *** particular,a tectonic reconstruction that spans multiple supercontinent cycles is important to understand the long-term evolution of Earth’s interior,surface environments and mineral ***,we present a new full-plate tectonic reconstruction from 1.8 Ga to present that combines and refines three published models:one full-plate tectonic model spanning 1 Ga to present and two continental-drift models focused on the late Paleoproterozoic to mesoproterozoic *** model is constrained by geological and geophysical data,and presented as a relative plate motion model in a paleomagnetic reference *** model encompasses three supercontinents,Nuna(Columbia),Rodinia,and Gondwana/Pangea,and more than two complete supercontinent cycles,covering40%of the Earth’s *** refinements to the base models are focused on times before 1.0 Ga,with minor changes for the *** times between 1.8 Ga and 1.0 Ga,the root mean square speeds for all plates generally range between 4 cm/yr and 7 cm/yr(despite short-term fast motion around 1.1 Ga),which are kinematically consistent with post-Pangean plate tectonic *** time span of the existence of Nuna is updated to between 1.6 Ga(1.65 Ga in the base model)and 1.46 Ga based on geological and paleomagnetic *** follow the base models to leave Amazonia/West Africa separate from Nuna(as well as Western Australia,which only collides with the remnants of Nuna after initial break-up),and South China/India separate from *** to the concept of a“boring billion”,our model reveals a dynamic geological history between 1.8 Ga and 0.8 Ga,characterized by supercontinent assembly and breakup,and continuous accretion *** model is publicly accessible,providing a framework for

关键词： Plate reconstruction Nuna Supercontinent Proterozoic Paleogeography

NUmERICAL SImULATION OF HEmODYNAmICS IN THE HOST BLOOD VESSEL AND mICROVASCULAR NETWORK GENERATED FROm TUmOR-INDUCED ANGIOGENESIS

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Journal of Hydrodynamics 2006年第6期18卷 727-735页

作者： ZHAO Gai-ping WU Jie XU Shi-xiong collins m.W. JIANG Yu-ping WANG Jian Department of mechanics and Engineering Science Fudan University Shanghai 200433 China Brunel Institute for Bioengineering School of Engineering and Design Brunel University Uxbridge MiddlesexUB8 3PH UK Department of Neurology Huashan Hospital Fudan University Shanghai 200040 China

Numerical simulation of hemodynamics under the combined effects of both the host blood vessel and the microvascular network, which is based on a 2-D tumor inside and outside vascular network generated from a discrete mathematical model of tumor-induced angiogenesis, is performed systemically. And a ＂microvascular network-- transport across microvascular network--flow in interstitium＂ model is developed to study the flow in solid tumor. Simulations are carried out to examine the effects of the variations of the inlet Reynolds number in the host blood vessel, the hydraulic conductivity of the microvascular wall, and interstitial hydraulic conductivity coefficient on the fluid flow in tumor microcirculation. The results are consistent with data obtained in terms of physiology. These results may provide some theoretical references and the bases for further clinical experimental research.

关键词： solid tumors host blood vessel microvascular network hemodynamics numerical simulation

ENHANCED TUmORIGENESIS BY SmALL, PROTRACTED DOSES OF DENSELY IONIZING RADIATION

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Chinese medical Journal 1994年第6期 16-21页

作者： m.m. ElkindDepartment of Radiological Health Sciences, Colorado State University, Fort collins, Colorado 80523, U.S.A.

Starting with observations that were first published in 1982. a series of additional findings led to the discovery of an important property of eel's in late G2/ mitosis. In addition to being the most sensitive to killing, cells in this age-interval were also shown to be the most sensitive to radiation-induced neoplastic transformation. In this work, C3H mouse cells, designated 10T1 / 2, were irradiated with fission-spectrum neutrons and assayed in vitro via the endpoint focus formation on a monolayer of normal cells. From these observations, a biophysical model was developed to explain the anomalous finding that the frequency of transformation by low doses was enhanced when the exposure was protracted. In contrast to transformation by X- and 7-rays where repair and kinetics during exposure play dominant roles, with radiations like reactor neutrons and a-particles repair has a minimal effect; only cell kinetics acts significantly to modify transformation due to protracted doses. In this report, the lack of responsiveness of mitotic cells to promotion by the phorbol ester 12-0-tetradecanoylphorbol-13-acetate is shown further to agree with the findings with fission-neutrons and the model that, at low dose rate, enhanced transformation is due principally to the progression of cells into the window of sensitivity. Implications of this model for lung cancer due to environmental radon are also discussed.

关键词： Res rate ENHANCED TUmORIGENESIS BY SmALL PROTRACTED DOSES OF DENSELY IONIZING RADIATION 口口 TPA

Gastrointestinal histoplasmosis complicating pediatric Crohn disease:A case report and review of literature

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World Journal of Gastrointestinal Endoscopy 2022年第10期14卷 648-656页

作者： C Quinn miller Omer A m Saeed Katrina collins Department of Pathology Indiana University School of MedicineIndianapolisIN 46202United States

BACKGROUND Infection with Histoplasma capsulatum(***)can lead to disseminated disease involving the gastrointestinal tract presenting as diffuse abdominal pain and diarrhea which may mimic inflammatory bowel disease(IBD).CASE SUmmARY We report a case of 12-year-old boy with presumptive diagnosis of Crohn disease(CD)that presented with several months of abdominal pain,weight loss and bloody *** showed patchy moderate inflammation characterized by erythema and numerous pseudopolyps involving the terminal ileum,cecum,and ascending *** sections from the colon biopsy revealed diffuse cellular infiltrate within the lamina propria with scattered histiocytic aggregates,and occasional non-necrotizing ***-Gomori’s methenamine Silver staining confirmed the presence of numerous yeast forms suggestive of Histoplasma spp.,further confirmed with positive urine Histoplasma antigen(6.58 ng/mL,range 0.2-20 ng/mL)and serum immunoglobulin G antibodies to Histoplasma(35.9 EU,range 10.0-80.0 EU).Intravenous amphotericin was administered then transitioned to oral ***-up computed tomography imaging showed a left lower lung nodule and mesenteric lymphadenopathy consistent with disseminated histoplasmosis *** Gastrointestinal involvement with *** with no accompanying respiratory symptoms is exceedingly rare and recognition is often delayed due to the overlapping clinical manifestations of *** case illustrates the importance of excluding infectious etiologies in patients with“biopsy-proven”CD prior to initiating immunosuppressive *** between clinicians and pathologists is crucial as blood cultures and antigen testing are key studies that should be performed in all suspected cases of histoplasmosis to avoid misdiagnosis and inappropriate treatment.

关键词： Crohn disease Disseminated histoplasmosis Endoscopy Colon Inflammatory bowel disease Immunosuppression Case report

method for hull-less barley transformation and manipulation of grain mixed-linkage beta-glucan

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Journal of Integrative Plant Biology 2018年第5期60卷 382-396页

作者： Wai Li Lim Helen m. collins Rohan R. Singh Natalie A. J. Kibble Kuok Yap Jillian Taylor Geoffrey B. Fincher Rachel A. Burton ARC Centre of Excellence in Plant Cell Walls School of Agriculture Food and Wine University of Adelaide Waite Campus Glen Osmond SouthAustralia 5064 Australia Institute for molecular Bioscience The University of Queensland，4072，Australia

Hull-less barley is increasingly offering scope for breeding grains with improved characteristics for human nutrition; however, recalcitrance of hull-less cultivars to transformation has limited the use of these varieties. To overcome this limitation, we sought to develop an effective transformation system for hull-less barley using the cultivar Torrens. Torrens yielded a transformation efficiency of 1.8%, using a modified Agrobacterium transformation method. This method was used to over-express genes encoding synthases for the important dietary fiber component, 0,3;1,4）-β-glucan （mixed-linkage glucan）, primarily present in starchy endosperm cell walls. Over-expression of the HvCslF6 gene, driven by an endosperm-specific promoter, produced lines where mixed-linkage glucan content increased on average by 45%, peaking at 70% in some lines, with smaller increases in transgenic HvCsIH1 grain. Transgenic HvCslF6 lines displayed alterations where grain had a darker color, were more easily crushed than wild type and were smaller. This was associated with an enlarged cavity in the central endosperm and changes in cell morphology, including aleurone and sub-aleurone cells. This work provides proof-of-concept evidence that mixed-linkage glucan content in hull-less barley grain can be increased by over-expression of the HvCslF6 gene, but also indicates that hull-less cultivars may be more sensitive to attempts to modify cell wall composition.

关键词： Tobias I. Baskin University of massachusetts USA

Single-atom heterogeneous catalysts based on distinct carbon nitride scaffolds

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National Science Review 2018年第5期5卷 642-652页

作者： Zupeng Chen Evgeniya Vorobyeva Sharon mitchell Edvin Fako Nuúria López Sean m.collins Rowan K.Leary Paul A.midgley RolAND Hauert Javier Pérez-Ramírez Institute for Chemical and Bioengineering Department of Chemistry and Applied BiosciencesETHZurich Institute of Chemical Research of Catalonia (ICIQ) The Barcelona Institute of Science and Technology 3. Department of Materials Science and MetallurgyUniversity of Cambridge 4. EmpaSwiss Federal Laboratories for Materials Science and Technology

Carbon nitrides integrating macroheterocycles offer unique potential as hosts for stabilizing metal atoms due to their rich electronic structure. To date, only graphitic heptazine-based polymers have been ***, we demonstrate that palladium atoms can be effectively isolated on other carbon nitride scaffolds including linear melem oligomers and poly(triazine/heptazine imides). Increased metal uptake was linked to the larger cavity size and the presence of chloride ions in the polyimide structures. Changing the host structure leads to significant variation in the average oxidation state of the metal, which can be tuned by exchange of the ionic species as evidenced by X-ray photoelectron spectroscopy and supported by density functional theory. Evaluation in the semi-hydrogenation of 2-methyl-3-butyn-2-ol reveals an inverse correlation between the activity and the degree of oxidation of palladium, with oligomers exhibiting the highest activity. These findings provide new mechanistic insights into the influence of the carbon nitride structure on metal stabilization.

关键词： single-atom heterogeneous catalysts carbon nitride scaffolds alkyne semi-hydrogenation density functional theory metal–host interaction

Environmental stress upon hepatopancreatic cells of freshwater prawns (Decapoda: Caridea) from the floodplain of ParanáRiver

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Natural Science 2010年第7期2卷 748-759页

作者： Pablo collins 不详

In order to evaluate the influence of stressed environments on hepatopancreatic cells of fre- shwater prawns, macrobachium borellii Nobili, 1896 and Palaemonetes argentinus Nobili 1901, (Crustacea, Decapoda, Palaemonidae) were collected at three different aquatic environments with different relationship to urban development in Argentina. Furthermore the effects of several cypermethryn concentration on hepa- topancreatic cell of m. borellii and P. argentinus were evaluated in a laboratory assays. The “N°1” lake (Santa Fe Argentina) which is more affected by the anthropogenic pressure and “Don Felipe” lake which is still not strongly by human activities were the studied sites from the floodplain of Paranáriver. While Alejandra lake was the intermedia effects sites. Different damaged ultra-structures were found in F- and R-cells of prawns in the stressed lake. The predominant features were: disrupted the microvillous border, swelled mitochondria, reduction of endoplasmic reticulum, dyctiosomes, glycoproteins, desna-turalization of vacuole membrane and premature autolysis. moreover the F-cell number was higher in the environment near to city than in the others sites. Similar effects were observed in the cypermethryn assays. The observations clearly indicate that the ultrastructure of midgut gland in the both palaemonids varies depending on the site from which animals are collected and the biocid presence. So, in this case it can be stated that the hepatopancreas histology of fre- shwater prawns is a good tool to monitor the impact of a stressed environment upon freshwater prawns.

关键词： Palaemonidae midgut Gland Shrimp Hepatopancreas Environmental Stress

Creation of an optic nerve sheath diameter ultrasound model for Neuro ICU education

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military medical Research 2021年第1期8卷 116-120页

作者： Heidi m.Felix Kristin A.Rosenbush Amy m.Lannen Robert A.Pooley Jason L.Siegel Benjamin L.Brown melissa L.mc mullan Christina I.collins William D.Freeman J.Wayne and Delores Barr Weaver Simulation Center Mayo Clinic4500 San Pablo RoadJacksonvilleFL 32224USA Division of medical Physics Mayo ClinicJacksonvilleFL 32224USA Department of Critical Care medicine Mayo ClinicJacksonvilleFL 32224USA Department of Neurology Mayo ClinicJacksonvilleFL 32224USA Department of Neurologic Surgery Mayo ClinicJacksonvilleFL 32224USA Department of Radiology Mayo ClinicJacksonvilleFL 32224USA Department of Nursing Mayo ClinicJacksonvilleFL 32224USA

Background: Using ultrasound to measure optic nerve sheath diameter(ONSD) is an emerging bedside technique to noninvasively assess intracranial pressure(ICP) in patients with brain injury. This technique is unique among bedside ultrasonography and is often performed by providers who have no formal ultrasound training. We sought to create a low-cost, 3 D, reusable ONSD model to train neurology, neurosurgery, and critical care providers in measuring ***: We identified 253 articles, of which 15 were associated with models and 2 with simulation. One gelatin model was reported, upon which we based our initial design. We could not validate the visual findings of this model;however, after constructing multiple beta models, the design most representative of human eye anatomy was a globe made of ballistics gel and either a 3 mm, 5 mm, or 7 mm×50 mm 3 D-printed optic nerve inserted into a platform composed of ballistics gel, all of which sat inside a 3 D-printed skull. This model was used to teach ONSD measurements with ultrasound at a continuing medical education event prior to training on a live human ***: A simple 3 D ballistic ONSD model allows learners to practice proper hand placement and pressure, basic landmarks, and ONSD measurement prior to operating on a human eye. This model is replicable and sustainable given that the globe and platform are composed of ballistics gel.

关键词： Intracranial pressure Simulation Task trainer Ultrasound