Novel ultrasound techniques in the identification of vulnerable plaques—an updated review of the literature

Atherosclerosis is an inflammatory disease partly mediated by lipoproteins. The rupture of vulnerable atherosclerotic plaques and thrombosis are major contributors to the development of acute cardiovascular events. Despite various advances in the treatment of atherosclerosis, there has been no satisfaction in the prevention and assessment of atherosclerotic vascular disease. The identification and classification of vulnerable plaques at an early stage as well as research of new treatments remain a challenge and the ultimate goal in the management of atherosclerosis and cardiovascular disease. The specific morphological features of vulnerable plaques, including intraplaque hemorrhage, large lipid necrotic cores, thin fibrous caps, inflammation, and neovascularisation, make it possible to identify and characterize plaques with a variety of invasive and non-invasive imaging techniques. Notably, the development of novel ultrasound techniques has introduced the traditional assessment of plaque echogenicity and luminal stenosis to a deeper assessment of plaque composition and the molecular field. This review will discuss the advantages and limitations of five currently available ultrasound imaging modalities for assessing plaque vulnerability, based on the biological characteristics of the vulnerable plaque, and their value in terms of clinical diagnosis, prognosis, and treatment efficacy assessment

The research of parallel to the grain compression performance test of laminated glued bamboo-wood composites

Istraživanje stlačivosti kompozita bambus-drvo predstavlja osnovu za izbor materijala za prednapregnute grede od bambusa i drveta i drugih komponenti čija se stlačivost uglavnom dijeli s kompozitima od lijepljenog bambusa i drveta. Odabrane su četiri vrste drveta i dvije vrste bambusa za 22 grupe (6 uzoraka u svakoj grupi) podijeljene u 4 serije za ispitivanje čimbenika koji utječu na vrstu materijala bambus/drvo, kao što su sastav, debljina ploče sloja (layer plate), i tipovi postavljanja lamela (lamina lay-ups type). Uspoređivani su i analizirani tlačna čvrstoća, modul elastičnosti, duktilnost i mehanizmi kvara. Rezultati su pokazali da je do loma uglavnom dolazilo zbog kosog smika (oblique shear failure), savijanja laminata, dok su se krajnji lokalni tlak i lom zbog uvijanja događali manje često. Tlačna čvrstoća bambusa bila je 1,5 ÷ 2 puta veća nego tlačna čvrstoća drveta. Njihov je modul elastičnosti sličan zbog čega se uobičajeno koriste u temeljima. Nakon sastavljanja, tlačna se čvrstoća povećala. Nakon sastavljanja s lijepljenim bambusom, povećala se za 1,26 ÷ 32,05 %, a s rekonsolidiranim bambusom (nanovo učvršćenim) se povećala za 0,80 ÷ 45,86 %. Kompoziti bambus-drvo imaju visoku čvrstoću i dobru duktilnost, što može zadovoljiti tehničke potrebe.Research of bamboo-wood composites compression performance provides a basis for material selections for prestressed glued bamboo-wood beams and other components whose compression is mainly shared by glued bamboo-wooden composites. Four kinds of wood and two kinds of bamboo were selected to comprise 22 groups (6 specimens each group) divided into 4 batches to study the influence factors on bamboo/wooden material type; factors such as composition pattern, layer plate thickness, and lamina lay-ups type. Compressive strength, elasticity modulus, ductility, and failure mechanisms were all compared and analysed. Results showed that failure modes were mainly oblique shear failure, laminates bending failure, laminates tackless failure, while the end local pressure and overall bending failure occured less frequently. Compressive strength of bamboo was 1,5 ÷ 2 times higher than that of wood. Elastic modulus of the two was similar, which makes them commonly used in foundations. After being compounded, compressive strength improved. After being combined with glued bamboo, it increased by 1,26 ÷ 32,05 %, and it increased by 0,80 ÷ 45,86 % with reconsolidated bamboo. Bamboo-wood composites have high strength and good ductility, which can meet engineering requirements

Experimental Study of Rock-like Materials with Two Unequal Parallel Preexisting Fissures under Uniaxial Compression

Fissures substantially impact the engineering stability of rock masses, making research on rock masses with preexisting fissures essential for engineering activities. The development of specimens with different preexisting fissure types was examined in this study. Three different types of specimens with preexisting fissures can be broadly categorized: specimens with few preexisting fissures, specimens with multiple preexisting fissures, and specimens with preexisting fissures and other flaws. Uniaxial compression tests of specimens with preexisting fissures of two unequal lengths were conducted, and the influence of preexisting fissure angle, the distance between the two fissures and fissure length on the peak strength and coalescence mode of specimens were analyzed. A large preexisting fissure length significantly influenced the peak strength and coalescence, and the uniaxial compressive strength (UCS) values of the rock-like materials decreased. In contrast, increasing the long preexisting fissure length influenced the crack propagation and coalescence more extensively in the case of a long preexisting fissure. The preexisting fissure angle and two preexisting fissure distances had a negligible effect on the UCS values of the rock-like materials. However, with increasing long preexisting fissure length, the short preexisting fissure was subject to crack propagation and coalescence

Experimental Study of Rock-like Materials with Two Unequal Parallel Preexisting Fissures under Uniaxial Compression

Fissures substantially impact the engineering stability of rock masses, making research on rock masses with preexisting fissures essential for engineering activities. The development of specimens with different preexisting fissure types was examined in this study. Three different types of specimens with preexisting fissures can be broadly categorized: specimens with few preexisting fissures, specimens with multiple preexisting fissures, and specimens with preexisting fissures and other flaws. Uniaxial compression tests of specimens with preexisting fissures of two unequal lengths were conducted, and the influence of preexisting fissure angle, the distance between the two fissures and fissure length on the peak strength and coalescence mode of specimens were analyzed. A large preexisting fissure length significantly influenced the peak strength and coalescence, and the uniaxial compressive strength (UCS) values of the rock-like materials decreased. In contrast, increasing the long preexisting fissure length influenced the crack propagation and coalescence more extensively in the case of a long preexisting fissure. The preexisting fissure angle and two preexisting fissure distances had a negligible effect on the UCS values of the rock-like materials. However, with increasing long preexisting fissure length, the short preexisting fissure was subject to crack propagation and coalescence

Early Cretaceous granitic rocks from the southern Jiaodong Peninsula, eastern China: implications for lithospheric extension

Zircon U-Pb ages, major element and trace element compositions, and Sr, Nd, and Pb isotopic compositions for late Mesozoic granites from the southern Jiaodong Peninsula (eastern China) were determined. Ages for the Wulianshan, Xiaozhushan, and Dazhushan plutons are 119.1-122.3, 114.2, and 108.9 Ma, respectively. Major and trace element characteristics show that these granitic rocks belong to alkaline, A-type granites formed in an extensional setting. Trace element compositions show strong, variable negative anomalies in Ba, K, P and Ti, and positive anomalies in Rb, Th, U, Pb, Ce, Zr, and Hf, which are typical characteristics of A-type granites. Variable Sr and Nd isotopic compositions, 87Sr/86Sr(i) = 0.70540-0.7071 and εNd(t) = -14.5 to -20.9. Whole-rock Pb isotopic compositions have the following ranges, (206Pb/204Pb)t = 15.707-16.561, (207Pb/204Pb)t = 15.376-16.462, and (208Pb/204Pb)t = 36.324 to 37.064. Isotopic modelling indicates an origin that lies between mantle tapped by Cenozoic basalts around the Tan-Lu megafault and lower continental crust (LCC), and which can be explained by mixing of 11-18% mantle and 82-89% LCC. Based on new and compiled data, we suggest that the southern Jiaodong Peninsula, as well as the Laoshan area, was in a regional extensional setting of an orogenic belt during 106-126 Ma. The granitic rocks may be the result of late Mesozoic lithospheric thinning and decratonization (i.e. late Mesozoic craton destruction event occurring throughout eastern China)

Radiocarbon isotope technique as a powerful tool in tracking anthropogenic emissions of carbonaceous air pollutants and greenhouse gases: A review

Air pollution and climate change are two important threats facing in our planet and are tightly linked to carbonaceous components in the atmosphere. A better understanding of the emission sources and environmental fate/sink of carbonaceous components is critical for improving our knowledge of the global carbon cycle and mitigating the negative environmental impacts of air pollution and climate change on human well-being. Radiocarbon (14C), which is decayed completely in fossil fuel (e.g. coal and petroleum), is an ideal tool for quantifying the carbon flow in various carbon reservoirs. This study reviews the current knowledge of 14C in organic carbon (OC), elemental carbon (EC), individual organic compounds, methane (CH4), carbon dioxide (CO2), annual plants, and tree rings. The impacts of fossil and non-fossil sources on the atmosphere can be quantified by measuring 14C. We also report on the influence of nuclear power plants and sea-air gas exchange on the abundance of 14C in the atmosphere. The increasing fossil fuel emissions indicated by the depletion of 14CO2 under IPCC RCP scenarios, support the urgent need to devise ambitious strategies of reducing carbonaceous components to achieve sustainable development on Earth. This review summarizes the challenges and perspectives of 14C studies of the atmosphere

Geochemistry of axial lavas from the mid-and southern Mariana Trough, and implications for back-arc magmatic processes

The Mariana Trough, a relatively simple intra-oceanic back-arc basin, is ideal for investigating magmatic processes and mantle- crust interaction in a subduction setting. We present new major- and trace element compositions for 31 basaltic lava and glass samples from the Mariana Trough back-arc spreading center. The studied lavas include phenocrysts of plagioclase, olivine and pyroxene. Major element compositions show that these lavas range from tholeiitic basalt to basaltic andesite, and belong to a sub- alkali tholeiitic series produced by fluid-influenced fractional crystallization of primary basaltic melts. Trace element composi- tions show that these lavas are transitional between typical normal mid-ocean ridge basalts (MORB) and island arc basalt (IAB), and are enriched in large ion lithophile elements (LILEs) and light rare earth elements (LREEs). Trace element ratios, e.g., Ba/Th, Pb/Ce, Th/Nd, La/Sm, Th/Nb, Ba/Nb and Th/Nb, indicate that the mantle from which these lavas were derived underwent modification resulting from the addition of multiple subduction components. Some typical trace element ratios (e.g., Ba/Nb- total subduction component, Ba/Th- shallow subduction, and Th/Nb-deep subduction component) from our new data and the literature suggest that a latitudinal variation exists in addition to subduction components, and indicates a more complex and heterogeneous distribution of subduction components in the Mariana back-arc region. We suggest that, (1) compared to back-arc locations at 18° N and 15.5° N, lavas from back-arc locations at 17° N indicate higher levels of modification by hydrous fluid released from the subducted slab, and (2) compared to back-arc locations at 17° N and 15.5° N, petrogenesis of lavas from back-arc locations at 18° N indicates a greater influence of sediment melt

An experimental study on synthesis of β-Sialon composites using fly ash and lignite char-preparation and whiskers formation

β-Sialon based composites were produced using a vertical reactor by carbothermal reduction reaction under nitrogen using fly ash and lignite chars to examine the effects of mixing, carbon content, reaction temperature and sintering time. The influences of chars as a reductant were further investigated in comparison with graphite. The evolution of phase and morphology in samples were analyzed by X-ray diffraction (XRD) and scanning electron microscope (SEM). Mechanical stirring was favored to mix fly ash and chars, while ball-milling shove the chars with porous structure due to collisions of agate balls, preventing N₂ penetration to the inner parts of reactants. When excess carbon was increased to 100%, a higher combustion reactivity of low-temperature chars resulted in the production of SiC phase. The evolution of β-Sialon with increasing reaction temperature showed the samples mixed with chars were more sensitive to reaction temperature than that with graphite. β-Sialon phase increased gradually with increasing sintering time to 6 h and decreased thereafter due to the decomposition or conversion of β-Sialon. These changes were more significantly for samples adding lignite chars. The optimal operation has been determined and rod-like β-Sialon whiskers with high aspect ratio appeared after performing the operation. In the growth process of whiskers, bead-shape whiskers were observed, suggesting that the growth mechanism was different from the conventional vaporliquidsolid (VLS) mechanism

Early Cretaceous granitic rocks from the southern Jiaodong Peninsula, eastern China: implications for lithospheric extension

<p>Zircon U–Pb ages, major element and trace element compositions, and Sr, Nd, and Pb isotopic compositions for late Mesozoic granites from the southern Jiaodong Peninsula (eastern China) were determined. Ages for the Wulianshan, Xiaozhushan, and Dazhushan plutons are 119.1–122.3, 114.2, and 108.9 Ma, respectively. Major and trace element characteristics show that these granitic rocks belong to alkaline, A-type granites formed in an extensional setting. Trace element compositions show strong, variable negative anomalies in Ba, K, P and Ti, and positive anomalies in Rb, Th, U, Pb, Ce, Zr, and Hf, which are typical characteristics of A-type granites. Variable Sr and Nd isotopic compositions, ⁸⁷Sr/⁸⁶Sr(i) = 0.70540–0.7071 and <i>ε</i>Nd(<i>t</i>) = −14.5 to −20.9. Whole-rock Pb isotopic compositions have the following ranges, (²⁰⁶Pb/²⁰⁴Pb)<i>t</i> = 15.707–16.561, (²⁰⁷Pb/²⁰⁴Pb)<i>t</i> = 15.376–16.462, and (²⁰⁸Pb/²⁰⁴Pb)<i>t</i> = 36.324 to 37.064. Isotopic modelling indicates an origin that lies between mantle tapped by Cenozoic basalts around the Tan-Lu megafault and lower continental crust (LCC), and which can be explained by mixing of 11–18% mantle and 82–89% LCC. Based on new and compiled data, we suggest that the southern Jiaodong Peninsula, as well as the Laoshan area, was in a regional extensional setting of an orogenic belt during 106–126 Ma. The granitic rocks may be the result of late Mesozoic lithospheric thinning and decratonization (i.e. late Mesozoic craton destruction event occurring throughout eastern China).</p