A tetra-n-butoxy zinc phthalocyanine (n-BuO)4ZnPc has been synthesized in a single step, starting from commercial precursors, and easily purified. The molecule can be solution processed to form an ...effective and inexpensive hole transport layer for organic and perovskite solar cells. These appealing features are suggested by the results of a series of chemical, optical, and voltammetric characterizations of the molecule, supported by the results of ab initio simulations. Preliminary measurements of (n-BuO)4ZnPc-methylammonium lead triiodide perovskite-based devices confirm such suggestion and indicate that the interface between the photoactive layer and the hole transporting layer is characterized by hole-extracting and electron-blocking properties, potentially competitive with those of other standards de facto in the field of organic hole transport materials, like the expensive Spiro-OMeTAD.
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FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UL, UM, UPUK
The historical development leading to, and the current status of, the spin-Hamiltonian (SH) formalisms, characterizing electron magnetic resonance (EMR), also referred to as electron paramagnetic (or ...spin) resonance (EPR or ESR), is reviewed. The spin-Hamiltonian concept is briefly outlined to set a framework for definitions of relevant terms. Meanings of the terms which are often confused with each other, e.g. physical versus effective Hamiltonian, real versus effective versus fictitious spin, microscopic SH (MSH), zero-field-splitting (ZFS) Hamiltonian, generalized SH (GSH), and phenomenological SH (PSH), are elucidated. Various general approaches to 'derive' MSH as well as to 'construct' GSH for transition ions are discussed. This enables clarification of relationship between the ZFS Hamiltonian and (a) the crystal-field (CF), (b) electronic spin-spin, and (c) nuclear-quadrupole Hamiltonians. The inadmissibility of the odd-order ZFS terms (l = 3, 5) is also discussed. A brief general classification of the major operator and parameter notations used in the literature to describe ZFS Hamiltonian is provided. Other important areas relevant to EMR, where the SH concept plays a central role, are outlined.
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BFBNIB, GIS, IJS, KISLJ, NUK, PNG, UL, UM, UPUK
Patients with percutaneous coronary intervention generally receive either bare metal stents or drug‐eluting stents to restore the normal blood flow. However, due to the lack of stent production with ...an individual patient in mind, the same level of effectiveness may not be possible in treating two different clinical scenarios. This study introduces for the first time the feasibility of a patient‐specific stenting process constructed from direct 3D segmentation of medical images using direct 3D printing of biodegradable polymer–graphene composite with dual drug incorporation. A biodegradable polymer–carbon composite is prepared doped with graphene nanoplatelets to achieve controlled release of combinatorics as anticoagulation and antirestenosis agents. This study develops a technology prototyped for personalized stenting. An in silico analysis is performed to optimize the stent design for printing and its prediction of sustainability under force exerted by coronary artery or blood flow. A holistic approach covering in silico to in situ–in vivo establishes the structural integrity of the polymer composite, its mechanical properties, drug loading and release control, prototyping, functional activity, safety, and feasibility of placement in coronary artery of swine.
The feasibility of a patient‐specific stenting process constructed from computed tomographic images is introduced. A biodegradable polymer–carbon composite is prepared, doped with graphene nanoplatelets to achieve controlled release of combinatorics as anticoagulation and antirestenosis agents. A technology prototyped for personalized stenting is developed.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
The effect of Bi (semimetal) nanoinclusions in nanostructured Bi2Te3 matrices is investigated. Bismuth nanoparticles synthesized by a low temperature solvothermal method are incorporated into Bi2Te3 ...matrix phases, synthesized by planetary ball milling. High density pellets of the Bi nanoparticle/Bi2Te3 nanocomposites are created by hot pressing the powders at 200 °C and 100 MPa. The effect of different volume fractions (0–7%) of Bi semimetal nanoparticles on the Seebeck coefficient, electrical conductivity, thermal conductivity and carrier concentration is reported. Our results show that the incorporation of semimetal nanoparticles results in a reduction in the lattice thermal conductivity in all the samples. A significant enhancement in power factor is observed for Bi nanoparticle volume fraction of 5% and 7%. We show that it is possible to reduce the lattice thermal conductivity and increase the power factor resulting in an increase in figure of merit by a factor of 2 (from ZT = 0.2 to 0.4). Seebeck coefficient and electrical conductivity as a function of carrier concentration data are consistent with the electron filtering effect, where low‐energy electrons are preferentially scattered by the barrier potentials set up at the semimetal nanoparticle/semiconductor interfaces.
Nanocomposites are fabricated by combining chemically synthesized bismuth nanoparticles with mechanically‐alloyed Bi2Te3. The resulting material displays electronic transport properties consistent with energy‐dependent electronic scattering from the potential barrier established at the semimetal/semiconductor interface. This general synthetic approach can be used to create nanocomposite materials with transport properties engineered for direct thermal to electrical energy conversion applications by appropriate selection of the matrix and nanoparticle inclusions.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Dynamic analysis and trajectory tracking of a Tethered Space Robot (TSR) is investigated in this paper. A hybrid controller is used to perform the control task. It consists of two components, the ...first one deals with librational motion of the tether, while the second one takes care of the manipulator motion. A Nonlinear Model Predictive Control (NMPC) approach is used to control the tether libration; for this purpose, the libration is described by a single degree of freedom and the tether length rate is employed as the input to suppress the librational motion. A modified Computed Torque Method (CTM) is used to control the manipulator motion. The dynamic interaction between the manipulator motion and the librational motion is considered both in the system dynamics and control of the system. Using numerical simulations, performance of the proposed control system is evaluated for end-effector positioning as well as for trajectory tracking for two cases: a Low Earth Orbit (LEO) and the Geostationary Earth Orbit (GEO).
•Librational motion of TSS is controlled by reel rate through a NMPC controller.•The MPC controller confines the tether length in a given range.•Tethered space robot is controlled by a hybrid CTM-MPC controller.•The method is used for positioning and trajectory tracking of TSR end-effector.•Performance of the method is evaluated numerically for several maneuvers.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
The present study examines the nonlinear behaviour of a cantilevered carbon nanotube (CNT) resonator and its mass detection sensitivity, employing a new nonlinear electrostatic load model. More ...specifically, a 3D finite element model is developed in order to obtain the electrostatic load distribution on cantilevered CNT resonators. A new nonlinear electrostatic load model is then proposed accounting for the end effects due to finite length. Additionally, a new nonlinear size-dependent continuum model is developed for the cantilevered CNT resonator, employing the modified couple stress theory (to account for size-effects) together with the Kelvin-Voigt model (to account for nonlinear damping); the size-dependent model takes into account all sources of nonlinearity, i.e. geometrical and inertial nonlinearities as well as nonlinearities associated with damping, small-scale, and electrostatic load. The nonlinear equation of motion of the cantilevered CNT resonator is obtained based on the new models developed for the CNT resonator and the electrostatic load. The Galerkin method is then applied to the nonlinear equation of motion, resulting in a set of nonlinear ordinary differential equations, consisting of geometrical, inertial, electrical, damping, and size-dependent nonlinear terms. This high-dimensional nonlinear discretized model is solved numerically utilizing the pseudo-arclength continuation technique. The nonlinear static and dynamic responses of the system are examined for various cases, investigating the effect of DC and AC voltages, length-scale parameter, nonlinear damping, and electrostatic load. Moreover, the mass detection sensitivity of the system is examined for possible application of the CNT resonator as a nanosensor.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
499.
Biomarkers of Immunosuppression Misra, Abinav K; Levy, Mitchell M; Ward, Nicholas S
Critical care clinics
36, Issue:
1
Journal Article
Peer reviewed
It is now recognized that sepsis is not a uniformly proinflammatory state. There is a well-recognized counter anti-inflammatory response that occurs in many patients. The timing and magnitude of this ...response varies considerably and thus makes its identification and manipulation more difficult. Studies in animals and humans have now identified a small number of biologic responses that characterize this immunosuppressed state, such as lymphocyte death, HLA receptor downregulation, and monocyte exhaustion. Researchers are now trying to use these as markers of individual immunosuppression to predict outcomes and identify patients who would and would not benefit from new immune stimulatory therapies.
•Anticoagulation status within or above the therapeutic range was maintained in 80.2% patients.•Anticoagulation status was not related to type and burden of risk factor.•Recanalization and outcome at ...3 months were not affected by coagulation status.•This study raises question about the duration of anticoagulation in CVT.
Effective anticoagulation status may determine the recanalization and outcome of cerebral venous thrombosis (CVT). We report impact of anticoagulation status on recanalization and outcome of CVT. This is a retrospective study on 126 patients with CVT diagnosed on magnetic resonance venography (MRV). Their clinical features and risk factors were noted. The data were retrieved from a prospectively maintained registry, and international normalized ratio (INR) was noted after discharge till 3 months. All the patients were on acenocoumarol. Based on INR value, patients were categorized as Group A (effective anticoagulation INR within the therapeutic range or above) and Group B (ineffective anticoagulation INR > 50% below the therapeutic range). A repeat MRV at 3 months was done for recanalization. Outcome at 3 months was evaluated using modified Rankin Scale (mRS), and categorized as good (mRS ≤ 2) and poor (mRS 2 or more) 101(80.2%) patients were in group A and 25(19.8%) in group B. Their demographic, risk factors, magnetic resonance imaging (MRI) and MRV findings were comparable. On repeat MRV, recanalization occurred in 22/24(91.7%); 15(88%) in group A and 7(100%) in group B. Recanalization was independent of coagulation status. Seven (5.6%) patients died and 107(84.9%) had good outcome; 85(84.2%) in group A and 22(88%) in group B. Kaplan Meier analysis also did not reveal survival or good outcome benefits between the groups. In CVT, outcome and recanalization at 3 months are not dependent on coagulation status. Further prospective studies are needed regarding duration of anticoagulant and its impact on recanalization and outcome.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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