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This study aimed to investigate the impact of branch vessel involvement on organ malperfusion and mid-term survival in patients with acute type A aortic dissection (ATAAD). Between January 2019 and December 2020, 493 consecutive patients with angiographically confirmed ATAAD were retrospectively analysed. Preoperative computed tomography angiography parameters (branch artery involvement, longitudinal extent of dissection) were reviewed. The incidence of organ malperfusion, in-hospital mortality, and mid-term outcomes of patients with and without branch vessel involvement were compared. Branch vessel involvement was detected in 407 patients (82.6%), and organ malperfusion was observed in 234 patients (47.5%). The incidence of organ malperfusion was significantly higher in patients with branch vessel involvement compared with patients without it (52.6% vs. 23.3%, p < 0.001). Patients with coronary artery involvement (32.5%) were more likely to manifest as clinical malperfusion, whereas it occurred only 19.4% in patients with renal artery involvement. In-hospital mortality was higher in patients with branch vessel involvement (19.9% vs. 8.1%, p = 0.010). Median follow-up time was 16.1 months. Two-year survival rate was lower in patients with branch vessel involvement (76.3% vs. 84.5%, p = 0.085) or organ malperfusion (68.3% vs. 86.0%, p < 0.001). Multivariable analysis identified cardiac, cerebral, visceral and renal malperfusion as independent predictors for in-hospital mortality. Only a small proportion of branch vessel involvement was associated with corresponding organ malperfusion in patients with ATAAD. Branch vessel involvement had a greater effect on short-term outcomes than mid-term survival, and organ malperfusion was related to a worse prognosis beyond it. • Most patients with ATAAD have branch vessel involvement. • Branch vessel involvement is not always associated with organ malperfusion. • Patients with coronary artery involvement are more likely to manifest as clinical malperfusion. • Patients with branch vessel involvement had a greater impact on in-hospital mortality than 2-year mortality. • Preoperative malperfusion was associated with a worse prognosis beyond branch vessel involvement. [ABSTRACT FROM AUTHOR]

Naturally sourced food ingredients have been the beneficiary of legal, regulatory and consumer preference as the result of a widely shared assumption of safety. However, the natural substances consumed in modernity may have little to do with the historically consumed part of the plant or even the plant itself. Further, our initial impression of a safe plant derivative may well be false as the result of the use of different growth conditions or, changes in harvesting and processing conditions that may have brought about a higher level of toxic constituents. Despite the variability of plant constituents, manufacturers' standards are set according to the content of commercially desirable properties, rather than presence of potentially toxic constituents. Why then, after all the potential reservations regarding naturals, is there such an enmity toward synthetic chemicals (including single chemical fermentation products), which have been tested in a systematic manner for potential toxic effects and whose composition is well known as the result of consistent manufacturing techniques and analytical controls? The authors will describe the paradigms used for natural products safety review and compare them with the safety criteria required for an “artificial” food ingredient. [ABSTRACT FROM AUTHOR]

Breast cancer metastasizes to bone in the majority of patients with advanced disease. We investigated the effects of inadequate dietary calcium (Ca) on bone turnover, tumor growth, and bone response to tumor in tibia inoculated with 4T1 mammary carcinoma cells. Nine-month-old female Balb/c mice were placed on an adequate Ca (5 g/kg diet, n = 30) or low Ca (80 mg/kg diet, n = 31) diet for 14 days, then injected intratibially with 1,000 4T1 cells (transfected with luciferase for bioluminescence imaging), and sacrificed at 5, 10, or 21 days post-inoculation (n = 7–10 mice/group). Control mice (n = 6/group) were injected with carrier and sacrificed at 10 days post-inoculation. Tibiae with muscle intact were excised and evaluated by microcomputed tomography and histology. In vivo bioluminescent imaging revealed that 4T1 cells metastasized to lung. Therefore, lungs were removed for quantification of tumor. Mice fed low Ca exhibited higher bone turnover and higher tibial lesion scores than mice fed adequate Ca. Lesion severity, manifested as cortical osteolysis and periosteal woven bone formation, and tumor cell infiltration to muscle, increased with time, irrespective of diet. However, for most skeletal endpoints the rates of increase were greater in mice consuming low Ca compared to mice consuming adequate Ca. Infiltration of tumor cells into adjacent muscle, but not metastasis to lung, was also greater in mice consuming low Ca diet. The findings suggest that high bone turnover due to Ca insufficiency results in greater local mammary tumor cell growth, cortical osteolysis, woven bone formation, and invasion to muscle in mice. [ABSTRACT FROM AUTHOR]

Raman spectra of tetragonal phase PbTeO 3 have been acquired from single-crystal sample synthesized by hydrothermal method. Theory calculations have been carried out to analyze the Raman spectra. Raman bands between 600 cm −1 and 800 cm −1 are attributed to the internal modes of Te-O bonds in TeO 3 pyramid, while Raman bands between 136 cm −1 and 400 cm −1 are assigned to the external modes of TeO 3 pyramid. The vibration corresponding to Raman frequencies below 119 cm −1 are consisted of Pb lattice modes and external modes of TeO 3 . The effects of pressure on the Raman spectrum of PbTeO 3 have been investigated up to 23 GPa. A splitting of 119 cm −1 peak was observed at 13.4 GPa, which may caused by the rotation of TeO 3 pyramid instead of the phase transition. [ABSTRACT FROM AUTHOR]

The phase transition of PbNiO3 from LiNbO3 structure to the perovskite structure has been observed between 4.4 and 9.5 GPa, which was investigated by high-pressure synchrotron x-ray powder diffraction at room temperature. Compression behavior of the two phases has been analyzed, and the c axis is the soft direction for LiNbO 3-type PbNiO3. The bulk modulus of the LiNbO3-type PbNiO3 is K0=184(3) GPa, K0′=4.5(9), and the perovskite type is K0=166(8) GPa, K0′=4.9(8). [ABSTRACT FROM AUTHOR]

Abstract: Powder mixture of graphite and silicon nitride with hexagonal structure (α/β-Si3N4) was ball-milled in nitrogen and compressed under ~16GPa/1800°C and ~18GPa/2000°C, to investigate the possibility for replacing Si atoms by C atoms in cubic spinel silicon nitride (c-Si3N4). The sintered samples were characterized by X-ray diffraction (XRD), hardness measurement, optical microscope, scanning electron microscopy (SEM) and high-resolution transmission electron microscopy (HRTEM). The results show that the well-sintered compacts were composed of nanocrystalline c-Si3N4 and nanocrystalline diamond, and neither C3N4 and CSi2N4 nor other reaction products of Si3N4 and C were observed. Vickers hardness test shows that the average hardness of the samples is 41–42GPa. As a comparison, phase-pure c-Si3N4 bulks also have been synthesized and their hardness was confirmed to be about 31GPa. The pure c-Si3N4 sintered bulks exhibit a high frangibility, but their fracture toughness could be largely improved by adding carbon (nanocrystalline diamond) in the sintered compacts. [Copyright &y& Elsevier]

Single-phase BC4N can be formed at high pressure and temperature, starting with either a mixture of diamond and cubic boron nitride or graphite and hexagonal boron nitride. The samples exhibit extreme Vickers hardness (85±4GPa), reaching the hardness of single crystal diamond. Within a random solid solution model, the X-ray diffraction patterns of cubic BC x N solid solutions were calculated. The results indicate that the prepared B–C–N materials are continuous solid solutions with a zinc-blende structure. [Copyright &y& Elsevier]

Cell pressures in the cubic press have been determined by means of differential thermal analysis (DTA) based on the known fusion curve of aluminum. The results compared favorably with those of the well-known fixed-point method, based on pressure-induced phase transitions in bismuth (I-II, 2.55 GPa) and thallium (II-III, 3.68 GPa). The high-pressure fusion curve of lead was measured using our calibrated results, which agreed well with those of the previous work. All of this was made possible by the development of a successful cell assembly for the DTA analyses in the cubic press. Details of the design are described in the present work. [ABSTRACT FROM AUTHOR]

The 1‐year mortality and health consequences of COVID‐19 in cancer patients are relatively underexplored. In this multicenter cohort study, 166 COVID‐19 patients with cancer were compared with 498 non‐cancer COVID‐19 patients and 498 non‐COVID cancer patients. The 1‐year all‐cause mortality and hospital mortality rates in Cancer COVID‐19 Cohort (30% and 20%) were significantly higher than those in COVID‐19 Cohort (9% and 8%, both P <.001) and Cancer Cohort (16% and 2%, both P < 0.001). The 12‐month all‐cause post‐discharge mortality rate in survival discharged Cancer COVID‐19 Cohort (8%) was higher than that in COVID‐19 Cohort (0.4%, P <.001) but similar to that in Cancer Cohort (15%, P =.084). The incidence of sequelae in Cancer COVID‐19 Cohort (23%, 26/114) is similar to that in COVID‐19 Cohort (30%, 130/432, P =.13). The 1‐year all‐cause mortality was high among patients with hematologic malignancies (59%), followed by those who have nasopharyngeal, brain, and skin tumors (45%), digestive system neoplasm (43%), and lung cancers (32%). The rate was moderate among patients with genitourinary (14%), female genital (13%), breast (11%), and thyroid tumors (0). COVID‐19 patients with cancer showed a high rate of in‐hospital mortality and 1‐year all‐cause mortality, but the 12‐month all‐cause post‐discharge mortality rate in survival discharged cancer COVID‐19 patients was similar to that in Cancer Cohort. Comparing to COVID‐19 Cohort, risk stratification showed that hematologic, nasopharyngeal, brain, digestive system, and lung tumors were high risk (44% vs 9%, P < 0.001), while genitourinary, female genital, breast, and thyroid tumors had moderate risk (10% vs 9%, P =.85) in COVID‐19 Cancer Cohort. Different tumor subtypes had different effects on COVID‐19. But if cancer patients with COVID‐19 manage to survive their COVID‐19 infections, then long‐term mortality appears to be similar to the cancer patients without COVID‐19, and their long‐term clinical sequelae were similar to the COVID‐19 patients without cancer. [ABSTRACT FROM AUTHOR]

Large-volume cubic presses are widely used in scientific research and industrial applications. However, their pressure capability is often limited to 6 GPa, which severely restricts their applications under extended pressures. In this work, we report a newly designed hybrid cell assembly for cubic presses by embedding six WC pressure-enhancing blocks into the pyrophyllite pressure-transmitting medium, leading to profoundly increased pressure efficiency (i.e. more than 40%), hence largely extended pressure conditions up to 8–9 GPa without sacrificing sample volume. Because of the optimized design, the expensive first-stage WC anvils are effectively protected, which makes the press routinely operated up to 8–9 GPa in avoiding damage of anvils. Through optimization of heating efficiency, temperature of the new assembly can reach above 2500°C. Using this high pressure cell, we have synthesized centimetre-sized polycrystalline cubic BN bulk sample by the direct transformation of hexagonal BN at 7.7 GPa and 2000°C. Successful implementation of large-volume cubic press up to 8–9 GPa and 2500°C would provide many opportunities for the synthesis of new materials on massive scale (e.g. novel superhard compounds) and for the study of materials at extended pressures. [ABSTRACT FROM AUTHOR]

Pure-phase polycrystalline cadmium tetraphosphide (CdP4) has been successfully synthesized under high pressures in a large volume cubic press, and the pressure-temperature (P-T) formation boundary of CdP4 from the Cd-P binary system has been determined. The equation of state of monoclinic CdP4 has also been evaluated by synchrotron-radiation angle-dispersive X-ray diffraction (ADXRD) under quasihydrostatic compression up to 26.4 GPa in a diamond-anvil cell. The ADXRD data yield a bulk modulus B0 = 94 ± 9 GPa with a pressure derivative B0′ = 8.0. The experimental data are discussed and compared to the results of first-principles calculations. [ABSTRACT FROM AUTHOR]

Copper ions are unavoidable in the process of copper-molybdenum flotation separation. The flotation response of chalcopyrite and molybdenite in the presence of copper ions was investigated through single mineral flotation tests and flotation separation tests. The influence mechanism was studied by adsorption experiments, zeta-potential measurements, and X-ray photoelectron spectroscopy (XPS) analysis. Flotation results indicated that copper ions dramatically reduced the recoveries of copper and molybdenum, and increased the inhibition effect of sodium sulfide; that is, the flotation separation of chalcopyrite and molybdenite was seriously hindered by copper ions. The adsorption experiments demonstrated that copper ions were adsorbed on molybdenite and chalcopyrite, and the adsorption amounts increased in the presence of sodium sulfide. The results of zeta-potential measurements confirmed that the floatability of the minerals was deteriorated by the adsorption of copper hydroxides (Cu(OH) + and Cu(OH) 2 ) and the subsequent adsorption of hydrosulfide ions (HS − ). Moreover, XPS analysis verified that the adsorbed copper hydroxides reacted with hydrosulfide ions, producing Cu(I)-S species on the surface of chalcopyrite and molybdenite. The adsorbed Cu(I) ions provided additional reaction sites and promoted the formation of a hydrophilic layer by the attachment of excessive hydrosulfide ions. Based on these analyses, a possible inhibition model for the interactions among the mineral surface, copper ions, and sulfide ions is proposed. [ABSTRACT FROM AUTHOR]

We report the high-pressure synthesis and elastic properties of stoichiometric cubic δ-NbN investigated by a combination of experiments and first principles calculations. Using the high pressure solid-state ion-exchange reaction route, we have successfully synthesized polycrystalline δ-NbN at 5.5 GPa and 1673 K. The refined lattice parameter of as-synthesized sample is 4.3960(6) Å, corresponding to the stoichiometric niobium nitride. The determined bulk modulus of δ-NbN is B0 = 319(2) GPa with [ABSTRACT FROM AUTHOR]

The diamond thick layers prepared using chemical vapor deposition (CVD) methods have been treated at high pressures and high temperatures (HP-HT). It was found that the Vickers hardness of the HP-HT treated bulks was nearly two times as high as that of the starting CVD diamond samples. The hardness of the samples treated at 8 GPa and 1800°C is ∼80 GPa at a loading force of 49 N, close to that of the single-crystal diamond (∼100 GPa). In addition, the oxidation resistance of CVD diamond samples was also enhanced greatly after HP-HT treatments, and the diamondization of sp2bonded carbon in the CVD diamond samples could occur at 7–8 GPa and 1600–1800°C. The HP-HT conditions of diamondization in our works are much lower than the case of the graphite-to-diamond direct transformation without the presence of catalyst (>15 GPa and 2000°C). [ABSTRACT FROM PUBLISHER]

ZrO 2 whiskers have been successfully synthesized at temperature of 1800 °C and high pressure of 15 GPa, using ZrO 2 powder as the starting material. After a high pressure and high temperature (HPHT) process, a bunch of long and idiomorphic ZrO 2 whiskers are obtained. The grown whiskers look like needles, and have silky luster. They are colorless and transparent, and exhibit hexagonal, triangular, quadrilateral, and irregular shaped cross sections. Through this HPHT method, whiskers with various diameters from 10 to 20 μm, and length from 200 to 1000 μm can be produced. The aspect ratio of length to diameter can be from 10 to 100. Growth mechanism of the ZrO 2 whiskers prepared under HPHT conditions are discussed, and the ZrO 2 whiskers growth may undergo a vapor–solid process. [ABSTRACT FROM AUTHOR]

Superhard materials are solids whose Vickers hardness is beyond 40 GPa. They have wide applications in industry such as cutting and polishing tools, wear-resistant coatings. Most preparations of superhard materials are conducted under extreme pressure and temperature conditions, not only for scientific investigations, but also for the practical applications. In this paper, we would introduce the recent progress on the design and preparations of novel superhard materials, mainly on nanopolycrystalline diamond, B-C-N superhard solid solutions, and cubic-SiN/diamond nanocomposites prepared under ultrahigh pressure and high temperature (HPHT), using multi-anvil apparatus based on the hinged-type cubic press. Bulk materials of all these superhard phases have been successfully synthesized and are systematically tested. We emphasize that ultra-HPHT method plays an important role in the scientific research and industrial production of superhard materials. It provides the driving forces for the light elements forming novel superhard phases as well as the way for sintering high-density nanosuperhard materials. [ABSTRACT FROM AUTHOR]

High pressure and high temperature synthesized MoB2and WB2compacts were investigated using X-ray diffraction, energy dispersive spectroscope, scanning electron microscope, Vickers indentation test and ultrasonic measurements. Experiments showed that both MoB2and WB2compacts are phase pure and with a grain size of 100–200 nm. Vickers indentation test under a large loading force of 49 N showed that the Vickers hardness of MoB2and WB2are about 21 and 22 GPa, respectively. The bulk modulus and shear modulus are about 296 GPa, and 190 GPa for MoB2and 349 and 200 GPa for WB2through ultrasonic measurements. Our results indicate that MoB2and WB2are both hard materials with a hardness similar to that of tungsten carbide, which is widely used in industry. [ABSTRACT FROM PUBLISHER]

Abstract: Well-crystallized graphite and high energy ball-milled graphite were treated under 16GPa and temperatures up to 2500°C. Our experiments indicated that the ball-milled graphite can completely transform to nano-polycrystalline diamond (NPD) at 2100°C, while the well-crystallized graphite required 2500°C. The samples were characterized by X-ray diffraction, optical microscope, scanning electron microscope, and Vickers indenter hardness test. We found that high pressure not only made the conversion of graphite to NPD thermodynamically preferred, but also reduced the needed activation energy barrier. By analyzing thermodynamics and kinetics of the transformation, we suggested a low boundary for NPD forming region based on the phase diagram of carbon, and the formation mechanisms of Nano-polycrystalline diamond. [Copyright &y& Elsevier]

Quantitative measurements of pressure gradients have been made in the pyrophyllite and magnesium oxide (MgO) pressure-transmitting mediums using large-volume cubic apparatus. The relationships of pressure gradients along the axis of symmetry of the pyrophyllite and MgO cubes versus corresponding cell pressures have been established at room temperature. Our experimental results indicated that the pressure gradients increase as the cell pressure increases and that the pressure gradient in the MgO pressure-transmitting medium is about twice as high as that in the pyrophyllite pressure-transmitting medium at the same cell pressure. When the cell pressure reaches 5.5 GPa, the pressure gradient along the axis of symmetry of the pyrophyllite cube is about 50 MPa/mm. When the cell pressure reaches 7.7 GPa, the pressure gradient along the axis of symmetry of the MgO cube is about 140 MPa/mm. The experimental data obtained in the present work not only adapt to the cubic apparatus but also provide reference for the tetrahedral press and the double-stage multi-anvil apparatus (the octahedral compression). [ABSTRACT FROM PUBLISHER]

Abstract: The directional growth experiments of graphite-like structured MoS2 crystallites have been conducted by utilizing a designed sample cell assembly under high pressure (2.0 and 5.0GPa) and high temperature (700°C). X-ray diffraction (XRD) and scanning electron microscope (SEM) are used to characterize the samples. The results show that the prepared nanocrystalline MoS2 (n-MoS2) crystals have a hexagonal layered structure. The crystal is uncovered to grow preferentially along the (002) plane, which indicates that the low-energy surface is the (002) plane of the crystal. The striking diffuse/broadening nature of Bragg reflection is also analyzed in details, and considered to be associated with the defect structures of the layers stacking and rotational disorder. Measurements of crystallite/grain size are performed by using XRD technique and SEM observation. The measurement results suggest that the traditional peak broadening analysis techniques, including Williamson–Hall formula and Scherrer equation, may not be suitable for the present poorly crystallized n-MoS2 situation. The results may be conducive to have an insight into the growth mechanism and defects analysis of the layer-structured materials. [Copyright &y& Elsevier]

An anvil-preformed gasket system has been developed to extend the pressure range for the widely used large volume cubic press without sacrificing the sample volume. The relationship of the sample chamber pressure versus press load for this system was calibrated at room temperature using transitions in Bi, Tl, and Ba. With similar sample volumes (8-11 mm in diameter and 8 mm in length), the anvil-preformed gasket system can generate pressures up to about 8.5 GPa, significantly higher than 6 GPa, which was generally the maximum pressure for the conventional anvil-gasket system. The details on the optimized design for the anvil-preformed gasket system are given in this note. [ABSTRACT FROM AUTHOR]

Undoped Bi2FeCrO6 and 10 at. % La-doped Bi2FeCrO6 were prepared by a high-pressure solid-state sintering method. The phase structure, electrical, ferroelectric, and magnetic properties have been investigated. It is shown that doping La can increase the resistivity by three orders of magnitude at room temperature. Furthermore, La-doped Bi2FeCrO6 shows an enhanced magnetization, about three times that of undoped Bi2FeCrO6, and a high coercivity of ∼210 Oe. [ABSTRACT FROM AUTHOR]