24 research outputs found

    Minimal information for studies of extracellular vesicles 2018 (MISEV2018):a position statement of the International Society for Extracellular Vesicles and update of the MISEV2014 guidelines

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    The last decade has seen a sharp increase in the number of scientific publications describing physiological and pathological functions of extracellular vesicles (EVs), a collective term covering various subtypes of cell-released, membranous structures, called exosomes, microvesicles, microparticles, ectosomes, oncosomes, apoptotic bodies, and many other names. However, specific issues arise when working with these entities, whose size and amount often make them difficult to obtain as relatively pure preparations, and to characterize properly. The International Society for Extracellular Vesicles (ISEV) proposed Minimal Information for Studies of Extracellular Vesicles (“MISEV”) guidelines for the field in 2014. We now update these “MISEV2014” guidelines based on evolution of the collective knowledge in the last four years. An important point to consider is that ascribing a specific function to EVs in general, or to subtypes of EVs, requires reporting of specific information beyond mere description of function in a crude, potentially contaminated, and heterogeneous preparation. For example, claims that exosomes are endowed with exquisite and specific activities remain difficult to support experimentally, given our still limited knowledge of their specific molecular machineries of biogenesis and release, as compared with other biophysically similar EVs. The MISEV2018 guidelines include tables and outlines of suggested protocols and steps to follow to document specific EV-associated functional activities. Finally, a checklist is provided with summaries of key points

    Research and Design of a Routing Protocol in Large-Scale Wireless Sensor Networks

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    无线传感器网络,作为全球未来十大技术之一,集成了传感器技术、嵌入式计算技术、分布式信息处理和自组织网技术,可实时感知、采集、处理、传输网络分布区域内的各种信息数据,在军事国防、生物医疗、环境监测、抢险救灾、防恐反恐、危险区域远程控制等领域具有十分广阔的应用前景。 本文研究分析了无线传感器网络的已有路由协议,并针对大规模的无线传感器网络设计了一种树状路由协议,它根据节点地址信息来形成路由,从而简化了复杂繁冗的路由表查找和维护,节省了不必要的开销,提高了路由效率,实现了快速有效的数据传输。 为支持此路由协议本文提出了一种自适应动态地址分配算——ADAR(AdaptiveDynamicAddre...As one of the ten high technologies in the future, wireless sensor network, which is the integration of micro-sensors, embedded computing, modern network and Ad Hoc technologies, can apperceive, collect, process and transmit various information data within the region. It can be used in military defense, biomedical, environmental monitoring, disaster relief, counter-terrorism, remote control of haz...学位:工学硕士院系专业:信息科学与技术学院通信工程系_通信与信息系统学号:2332007115216

    GPU-accelerated Interval Arithmetic to solve the Apollonius Problem applied to a Stereo Drift Chamber

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    International audienceWe propose a new system of equations which identifies the helix common to all drift distance hits produced by a full stereo drift chamber detector when a charged particle passes through this detector. The equation system is obtained using the Apollonius' problem as guideline which gives it a very simple form and a clear physics interpretability as the case of full axial drift chamber detector. The proposed method is evaluated using drift distance hits constructed from Monte Carlo-generated helix trajectory tracks. The equation system is solved using a robust accelerated GPU brute-force algorithm based on interval arithmetic. All code is written using the Julia programming language

    Phase diagram of the orthorhombic, lightly lutetium doped EuMnO 3 magnetoelectric system

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    International audienceThis paper reports on structural, magnetic, dielectric, thermodynamic, and magnetodielectric properties of Eu1−xLuxMnO3, with 0 ⩽ x ⩽ 0.2, towards the (x, T) phase diagram. The phase diagram reflects the effect of lattice distortions induced by the isovalent substitution of Eu3+ by smaller Lu3+ ions, which gradually unbalances the antiferromagnetic against the ferromagnetic exchange interactions, enabling the emergence of both ferroelectricity and magnetoelectric coupling. For x < 0.1, the paramagnetic phase is followed by a presumably incommensurate collinear antiferromagnetic phase AFM-1, and then a weak ferromagnetic phase seems to be established, with a canted A-type antiferromagnetic order. For 0.1 ⩽ x ⩽ 0.2, the AFM-1 phase is followed by an antiferromagnetic phase AFM-2 with modulated spiral spin arrangement, compatible with ferroelectricity. The disappearance of hysteresis cycles P(E) at low temperatures, clearly indicates the existence of an antiferromagnetic phase AFM-3, whose spin structure is not compatible with both the ferroelectric and ferromagnetic components. The magnetic behavior of EuMnO3 and Eu0.9Lu0.1MnO3 suggests the existence of a phase line separating the AFM-1 phase from the AFM-2 and AFM-3 phases, which is observed for x = 0.1. Magnetodielectric coupling was evidenced for both x = 0.1 and 0.2 compositions. Ferroelectric polarization and magnetodielectric coupling coefficient are larger for the latter composition

    Mechanisms of endoderm formation in a cartilaginous fish reveal ancestral and homoplastic traits in jawed vertebrates

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    In order to gain insight into the impact of yolk increase on endoderm development, we have analyzed the mechanisms of endoderm formation in the catshark S. canicula, a species exhibiting telolecithal eggs and a distinct yolk sac. We show that in this species, endoderm markers are expressed in two distinct tissues, the deep mesenchyme, a mesenchymal population of deep blastomeres lying beneath the epithelial-like superficial layer, already specified at early blastula stages, and the involuting mesendoderm layer, which appears at the blastoderm posterior margin at the onset of gastrulation. Formation of the deep mesenchyme involves cell internalizations from the superficial layer prior to gastrulation, by a movement suggestive of ingressions. These cell movements were observed not only at the posterior margin, where massive internalizations take place prior to the start of involution, but also in the center of the blastoderm, where internalizations of single cells prevail. Like the adjacent involuting mesendoderm, the posterior deep mesenchyme expresses anterior mesendoderm markers under the control of Nodal/activin signaling. Comparisons across vertebrates support the conclusion that endoderm is specified in two distinct temporal phases in the catshark as in all major osteichthyan lineages, in line with an ancient origin of a biphasic mode of endoderm specification in gnathostomes. They also highlight unexpected similarities with amniotes, such as the occurrence of cell ingressions from the superficial layer prior to gastrulation. These similarities may correspond to homoplastic traits fixed separately in amniotes and chondrichthyans and related to the increase in egg yolk mass
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