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A Comparative Study of the Effect of Gold Seed Particle Preparation Method on Nanowire Growth

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Nano Research 2010年第7期3卷 506-519页

作者： Maria E.Messing Karla Hillerich Jessica Bolinsson Kristian Storm Jonas Johansson Kimberly A.Dick Knut Deppert Solid State Physics Lund UniversityBox 118S-22100 LundSweden Polymer&Materials Chemistry Lund UniversityBox 124S-22100 LundSweden

Highly controlled particle-assisted growth of semiconductor nanowires has been performed for many years,and a number of novel nanowire-based devices have been *** control of the epitaxial growth is required to optimize the performance of devices,and gold seed particles are known to provide the most controlled *** nanowire growth from gold particles generated and deposited by various different methods has been reported,but no investigation has yet been performed to compare the effects of gold particle generation and deposition methods on nanowire *** this article we present a direct comparative study of the effect of the gold particle creation and deposition methods on nanowire growth characteristics and nanowire crystal structure,and investigate the limitations of the different generation and deposition methods used.

关键词： Nanowire growth nanoparticles gold epitaxy electron microscopy

Intervention on toll-like receptors in pancreatic cancer

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World Journal of Gastroenterology 2014年第19期20卷 5808-5817页

作者： Juan Vaz Roland Andersson Department of Surgery Clinical Sciences LundSkne University Hospital LundLund UniversitySE-221 85 LundSweden

Pancreatic ductal adenocarcinoma(PDA)is a devastating disease with pronounced morbidity and a high mortality *** available treatments lack convincing cost-efficiency determinations and are in most cases not associated with relevant success *** stimulation of the immune system in murine PDA models has revealed some promising *** receptors(TLRs)are pillars of the immune system that have been linked to several forms of malignancy,including lung,breast and colon *** humans,TLRs are expressed in the pancreatic cancer tissue and in several cancer cell lines,whereas they are not expressed in the normal *** the present review,we explore the current knowledge concerning the role of different TLRs associated to *** if almost all known TLRs are expressed in the pancreatic cancer microenvironment,there are only five TLRs suggested as possible therapeutic *** data points at TLR2 and TLR9 as effective tumor markers and agonists could potentially be used as *** adjuvant *** elucidation of the role of TLR3 in PDA is only in its initial *** inhibition/blockage of TLR4-related pathways has shown some promising effects,but there are still many steps left before TLR4 inhibitors can be considered as possible therapeutic ***,TLR7 antagonists seem to be potential candidates for *** of their potential in immunotherapies,all existing data indicate that TLRs are strongly involved in the pathophysiology and development of PDA.

关键词： Pancreatic cancer Pathophysiological mechanism Toll-like receptor Intervention Adjuvant therapy

Small scale adeno-associated virusvector production for preclinical gene delivery based on chloroform precipitation

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Neural Regeneration Research 2022年第1期17卷 99-100页

作者： Marcus Davidsson Andreas Heuer Molecular Neuromodulation Department of Experimental Medical SciencesLund UniversityLundSweden Behavioural Neuroscience Laboratory Department of Experimental Medical SciencesLund UniversityLundSweden

Gene therapy aims to introduce genetic information into a cell-type of interest to replace,correct,silence,or modify defective *** therapy in its broadest sense can theoretically prevent,halt,or cure any condition that affects *** addition to that,the introduction and/or manipulation of genes is one of the major research areas in biological sciences,aimed to deepen our knowledge on how biological systems *** advances have made it possible to induce changes ranging from manipulations of large stretches of the genome to the change of single *** gold-standard vehicles to bring this genetic information into the target cells are viral vectors.

关键词： replace Small mankind

Morphology of living cells cultured on nanowire arrays with varying nanowire densities and diameters

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Science China(Life Sciences) 2018年第4期61卷 427-435页

作者： Zhen Li Henrik Persson Karl Adolfsson Stina Oredsson Christelle N. Prinz Division of Solid State Physics Lund University Lund 22100 Sweden Nano lund Lund University Lund 22100 Sweden Department of Biology Lund 22362 Sweden Present address: Translational & Bioengineering Program Mechanical and Industrial Engineering University of Toronto Toronto MSG 1M1 ON Canada

Vertical nanowire arrays are increasingly investigated for their applications in steering cell behavior. The geometry of the array is an important parameter, which influences the morphology and adhesion of cells. Here, we investigate the effects of array geometry on the morphology of MCF7 cancer cells and MCF10A normal-like epithelial cells. Different gallium phosphide nanowire array-geometries were produced by varying the nanowire density and diameter. Our results show that the cell size is smaller on nanowires compared to flat gallium phosphide. The cell area decreases with increasing the nanowire density on the substrate. We observed an effect of the nanowire diameter on MCF10A cells, with a decreased cell area on 40 nm diameter nanowires, compared to 60 and 80 nm diameter nanowires in high-density arrays. The focal adhesion morphology depends on the extent to which cells are contacting the substrate. For low nanowire densities and diameters, ceils are lying on the substrate and we observed large focal adhesions at the cell edges. In contrast, for high nanowire densities and diameters, cells are lying on top of the nanowires and we observed point-like focal adhesions distributed over the whole cell. Our results constitute a step towards the ability to fine-tune cell behavior on nanowire arrays.

关键词： nanowires cell morphology diameter density aspect ratio

Brain natriuretic peptide is a potent vasodilator in aged human microcircula- tion and shows a blunted response in heart failure patients

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Journal of Geriatric Cardiology 2014年第1期11卷 50-56页

作者： Marie-Louise Edvinsson Erik Uddman Lars Edvinsson Sven E. Andersson Department of Emergency and Internal Medicine Institute of Clinical Sciences Lund University Lund University Hospital SE- 221 85 Lund Sweden

Background Brain natriuretic peptide （BNP） is normally present in low levels in the circulation, but it is elevated in parallel with the degree of congestion in heart failure subjects （CHF）. BNP has natriuretic effects and is a potent vasodilator. It is suggested that BNP could be a therapeutic alternative in CHF. However, we postulated that the high levels of circulating BNP in CHF may downregulate the response of microvascular natriuretic receptors. This was tested by comparing 15 CHF patients （BNP 〉 3000 ng/L） with 10 matched, healthy controls. Methods Cutaneous microvascular blood flow in the forearm was measured by laser Doppler Flowmetry. Local heating （＋44°C, 10 min） was used to evoke a maximum local dilator response. Results Non-invasive iontophoretic administration of either BNP or acetylcholine （ACh）, a known endothelium-dependent dilator, elicited an increase in local flow. The nitric oxide synthase inhibitor, l-N-Arginine- methyl-ester （L-NAME）, blocked the BNP response （in controls）. Interestingly, responses to BNP in CHF patients were reduced to about one third of those seen in healthy controls （increase in flow： 251% in CHF vs. 908% in controls; P 〈 0.001）. In contrast, the vasodilator responses to ACh and to local heating were only somewhat attenuated in CHF patients. Thus, dilator capacity and nitric oxide signalling were not af- fected to the same extent as BNP-mediated dilation, indicating a specific downregulation of the latter response. Conclusions The findings show for the first time that microvascular responses to BNP are markedly reduced in CHF patients. This is consistent with the hypothesis of BNP receptor function is downregulated in CHF.

关键词： Heart failure Cutaneous microcirculation Endothelial responses Acetylcholine, Brain natriuretic peptide Nitric oxide

SDI planning using the system dynamics technique within a community of practice:lessons learnt from Tanzania

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Geo-Spatial Information Science 2015年第2期18卷 97-110页

作者： Ali MANSOURIAN Alex LUBIDA Petter PILESJÖ Ehsan ABDOLMAJIDI Monica LASSI GIS Center Department of Physical Geography and Ecosystem ScienceLund UniversitySölvegatan 1222362 LundSweden Department of Research and Study Services Lund University LibraryLund UniversityHelgonabacken 1Box 3SE-22100 LundSweden

There exist major challenges in accelerating the spatial data infrastructure(SDI)planning process in the developing countries as well as advocating for politicians to support the development of SDI,due to the high complexity of SDI,lack of knowledge and experience,and limited insight in the *** address these challenges,a methodology for SDI planning in Tanzania,based on the system dynamics technique and the communities of practice concept,was adopted and applied within a community consisting of experts from stakeholder *** groups gathered to develop an SDI plan,while they shared their knowledge and discussed their ideas that helped their understanding of *** running the system dynamics model,the development of SDI over time could be simulated that gave the planning community an insight about the future effects of today’s plans and ***,an optimum model could be developed by refinements and improvements done with the consensus of the SDI *** model included the components and policies that are essential for a successful SDI implementation in Tanzania and can be used as a basis for SDI planning and help to gain political *** learnt from this research were promising regarding the usability of the methodology for SDI planning in comparable countries.

关键词： spatial data infrastructure(SDI) planning system dynamics technique community of practice

Mitophagy:From the dark into the spotlight

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Molecular Plant 2023年第10期16卷 1487-1489页

作者： Vivian Schmitt Olivier Van Aken Department of Biology Lund UniversityLundSweden

Despite the generally placid appearance of plants,many dynamicprocesses take place inside a plant *** such process thathas garnered attention in recent years is termed"autophagy."While originally discovered in yeast,our understanding of autophagy in plants has improved *** is considered a cellular recycling system in which cellular components oreven entire organelles can be encapsulated by a membranestructure(autophagosome)and then transported to the vacuole(in plants)for degradation and re-use.

关键词： attention organelle spite

Ultrafast photoinduced dynamics in quantum dot-based systems for light harvesting

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Nano Research 2015年第7期8卷 2125-2142页

作者： Kaibo Zheng Khadga Karki Karel Zidek Tonu Pullerits Department of Chemical Physics Lund University Box 124 22 100 Lund Sweden

Colloidal semiconductor nanocrystals, referred to as quantum dots, offer simple low-temperature solution-based methods for constructing optoelectronic devices such as light emitting diodes and solar cells. We review recent progress in the understanding of photoinduced processes in key components of a certain type of quantum dot solar cells where the dots sensitize a suitable metal oxide, such as ZnO or TiO2, for electron injection, and NiO for hole injection. The electron and hole injection dynamics are discussed in detail as a function of the quantum dot size and core-shell structure, the linker molecule type, and the morphology of the accepting metal oxide. Hole trapping is identified as a major factor limiting the performance of quantum dot-based devices. We review possible strategies for improvement that use core-shell structures and directed excitation energy transfer between quantum dots. Finally, the generation and injection of multiple excitons are revisited. We show that the assumption of a linear relationship between the intensity of transient absorption signal and the number of excitons does not generally hold, and this observation can partially explain highly disparate results for the effidency of generating multiple exdtons. A consistent calculation procedure for studies of multiple exciton generation is provided. Finally we offer a brief personal outlook on the topic.

关键词： colloidal quantum dots electron transfer, energy transfer,core shell quantum dots, quantum dot solar cell

Genome differentiation in Magonoliaceae as revealed from meiotic pairing in interspecific and intergeneric hybrids

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Journal of Systematics and Evolution 2011年第6期49卷 518-527页

作者： Erland EJDER University of lund and Swedish Magnolia Group

The cross compatibility within and between Yulania Spach and Michelia L.(Magnoliaceae) is relatively good and various such hybrids,obtained by conventional artificial hybridization,are *** aim of the present study was to determine the extent of genome differentiation between the species involved in these crosses through the observation of chromosome pairing during meiosis in pollen mother cells(PMCs) of the *** pairing behavior was studied in five species(2n = 38) and two interspecific hybrids of Michelia,eight species(2n = 38,76 and 114) and 10 interspecific hybrids of Yulania,and three intergeneric hybrids between Michelia and *** results showed that chromosome pairing was normal with bivalent formation in diploid parental species and in interspecific *** addition to bivalents,multivalents were encountered in polyploid parental species and polyploid interspecific *** the intergeneric hybrids between a tetraploid Yulania and two diploid Michelia,19 chromosomes,most likely originating from Michelia,were unable to synapse from zygotene to metaphase *** chromosome pairing indicated a high degree of homology between species within Michelia and Yulania and less homology between the genomes of these two *** differentiation of morphological characters and the distinctness of natural distribution also support the conclusion that these two genera are likely independent monophyletic *** suggests that the two genera were split at early evolution of Magnoliaceae and the overlapping characteristics in external morphology and internal structures of the two genera may be the result of parallel evolution or ancient common ancestry.

关键词： intergeneric hybrids interspecific hybrids Magnoliaceae meiotic behavior Michelia Yulania.