504 research outputs found
Alien Registration- Begin, Leo P. (West Forks, Somerset County)
https://digitalmaine.com/alien_docs/4322/thumbnail.jp
Basement-cover relations and internal structure of the Cape Smith klippe: A 1.9 Ga greenstone belt in northern Quebec, Canada
The Cape Smith Belt is a 380x60 km tectonic klippe composed of greenschistto amphibolite-grade mafic and komatiitic lava flows and fine-grained quartzose sediment, intruded by minor syn- to post-tectonic granitoids. Previously studied transects in areas of relatively high structural level show that the belt is constructed of seven or more north-dipping thrust sheets which verge toward the Superior Province (Archean) foreland in the south and away from an Archean basement massif (Kovik Antiform) external to the Trans-Hudson Orogen (Early Proterozoic) in the north. A field project (mapping and structural-stratigraphic-metamorphic studies) directed by MRS was begun in 1985 aimed at the structurally deeper levels of the belt and underlying basement, which are superby exposed in oblique cross-section (12 km minimum structural relief) at the west-plunging eastern end of the belt. Mapping now complete of the eastern end of the belt confirms that all of the metavolcanic and most of the metasedimentary rocks are allochthonous with respect to the Archean basement, and that the thrusts must have been rooted north of Kovik Antiform. The main findings follow
A detailed investigation of the onion structure of exchanged coupled magnetic Fe3-dO4@CoFe2O4@Fe3-dO4 nanoparticles
Nanoparticles that combine several magnetic phases offer wide perspectives for cutting edge applications because of the high modularity of their magnetic properties. Besides the addition of the magnetic characteristics intrinsic to each phase, the interface that results from core-shell and, further, from onion structures leads to synergistic properties such as magnetic exchange coupling. Such a phenomenon is of high interest to overcome the superparamagnetic limit of iron oxide nanoparticles which hampers potential applications such as data storage or sensors. In this manuscript, we report on the design of nanoparticles with an onion-like structure which has been scarcely reported yet. These nanoparticles consist of a Fe3-dO4 core covered by a first shell of CoFe2O4 and a second shell of Fe3-dO4, e.g., a Fe3-dO4@CoFe2O4@Fe3-dO4 onion-like structure. They were synthesized through a multistep seed-mediated growth approach which consists consists in performing three successive thermal decomposition of metal complexes in a high-boiling-point solvent (about 300 °C). Although TEM micrographs clearly show the growth of each shell from the iron oxide core, core sizes and shell thicknesses markedly differ from what is suggested by the size increasing. We investigated very precisely the structure of nanoparticles in performing high resolution (scanning) TEM imaging and geometrical phase analysis (GPA). The chemical composition and spatial distribution of atoms were studied by electron energy loss spectroscopy (EELS) mapping and spectroscopy. The chemical environment and oxidation state of cations were investigated by 57Fe Mössbauer spectrometry, soft X-ray absorption spectroscopy (XAS) and X-ray magnetic circular dichroism (XMCD). The combination of these techniques allowed us to estimate the increase of Fe2+ content in the iron oxide core of the core@shell structure and the increase of the cobalt ferrite shell thickness in the core@shell@shell one, whereas the iron oxide shell appears to be much thinner than expected. Thus, the modification of the chemical composition as well as the size of the Fe3-dO4 core and the thickness of the cobalt ferrite shell have a high impact on the magnetic properties. Furthermore, the growth of the iron oxide shell also markedly modifies the magnetic properties of the core-shell nanoparticles, thus demonstrating the high potential of onion-like nanoparticles to accurately tune the magnetic properties of nanoparticles according to the desired applications. © 2021 American Chemical Society
Nanotrench for nano and microparticle electrical interconnects
We present a simple and versatile patterning procedure for the reliable and reproducible fabrication of high aspect ratio (10 4 ) electrical interconnects that have separation distances down to 20 nm and lengths of several hundreds of microns. The process uses standard optical lithography techniques and allows parallel processing of many junctions, making it easily scalable and industrially relevant. We demonstrate the suitability of these nanotrenches as electrical interconnects for addressing micro and nanoparticles by realizing several circuits with integrated species. Furthermore, low impedance metal-metal low contacts are shown to be obtained when trapping a single metal-coated microsphere in the gap, emphasizing the intrinsic good electrical conductivity of the interconnects, even though a wet process is used. Highly resistive magnetite-based nanoparticles networks also demonstrate the advantage of the high aspect ratio of the nanotrenches for providing access to electrical properties of highly resistive materials, with leakage current levels below 1 pA. © 2010 IOP Publishing Ltd
Berenstein-Zelevinsky triangles, elementary couplings and fusion rules
We present a general scheme for describing su(N)_k fusion rules in terms of
elementary couplings, using Berenstein-Zelevinsky triangles. A fusion coupling
is characterized by its corresponding tensor product coupling (i.e. its
Berenstein-Zelevinsky triangle) and the threshold level at which it first
appears. We show that a closed expression for this threshold level is encoded
in the Berenstein-Zelevinsky triangle and an explicit method to calculate it is
presented. In this way a complete solution of su(4)_k fusion rules is obtained.Comment: 14 page
Childhood Maltreatment, Adolescent Psychological Difficulties and Borderline Personality Features: A Person-Centered Approach
Childhood maltreatment is a well-known risk factor for poor psychological outcomes across the lifecycle, including internalizing and externalizing difficulties, personality pathology and non-suicidal self-injury (NSSI). Much less is known regarding the associations between specific types and combinations of maltreatment and these difficulties during adolescence. Given the limitations of variable-centered approaches that focus on correlations and associations, the present study used a person-centered approach (Latent Class Analysis) to examine whether groups of adolescents who experience specific types and combinations of maltreatment reported more internalizing and externalizing difficulties, borderline personality features, or NSSI. Participants were 327 adolescents and young adults aged 12 to 21 from the community, with 32% reporting some experiences of maltreatment. The findings indicate that for adolescents and young adults in the community, sexual abuse, as well as neglect and antipathy in combination with other forms of maltreatment were associated with significantly higher self-reported distress and dysfunction. Sexual abuse was linked to more internalizing difficulties, borderline personality features and NNSI, whereas both neglect and antipathy were associated with more internalizing and externalizing difficulties. Furthermore, neglect was associated with significantly more episodes of NNSI and antipathy with more self-reported borderline personality features
Leptin-induced lipolysis opposes the tonic inhibition of endogenous adenosine in white adipocytes
The aim of the present study was to gain insight into the signaling pathway used
by leptin to stimulate lipolysis. The lipolytic rate of white adipocytes from
sex- and age-matched lean (+/+) and fa/fa rats was determined in the absence or
presence of leptin together with a number of agents acting at different levels of
the signaling cascade. Leptin did not modify FSK-, dbcAMP-, and IBMX-stimulated
lipolysis. Lipolysis can also be maximally stimulated by lowering media adenosine
levels with adenosine deaminase (ADA), i.e., in the ligand-free state. Although
ADA produced near maximal lipolysis in adipocytes of lean animals, only half of
the maximal lipolytic rate (50.9+/-3.2%) was achieved in fat cells from fa/fa
rats (P=0.0034). In adipocytes from lean animals preincubated with ADA, leptin
caused a concentration-related stimulation of lipolysis (P=0.0001). However,
leptin had no effect on the lipolytic activity of adipocytes in the ligand-free
state from fa/fa rats. The adenosine A1 receptor agonist CPA effectively
inhibited basal lipolysis in both lean and obese adipocytes (P=0.0001 and
P=0.0090, respectively). Leptin had no effect on the lipolytic rate of adipocytes
isolated from fa/fa rats and preincubated with CPA. When adipocytes were
incubated with the A1 receptor antagonist DPCPX, a significant increase in
glycerol release was observed in fa/fa fat cells (P=0.009), whereas cells
isolated from lean rats showed no differences to ADA-stimulated lipolysis. After
pretreatment with PTX, which inactivates receptor-mediated Gi function,
adipocytes of obese rats became as responsive to the stimulatory actions of ISO
as cells from lean rats (P=0.0090 vs. ISO in fa/fa rats; P=0.2416 vs. lean rats,
respectively). PTX treatment of lean cells, however, did not alter their response
to this lipolytic agent. It can be concluded that the lipolytic effect of leptin
is located at the adenylate cyclase/Gi proteins level and that leptin-induced
lipolysis opposes the tonic inhibition of endogenous adenosine in white
adipocytes
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