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The purpose of this study was to test the diagnostic performance of 3-D power Doppler ultrasound (3-D-PD) with the virtual organ computer-aided analysis (VOCAL) technique in the detection of prostate cancers (PCa). A total of 99 male patients referred for needle prostate biopsy owing to elevated serum prostate-specific antigen or abnormal direct rectal examination were prospectively included. The transrectal 3-D-PD-VOCAL quantitative vascularity parameters of vascularization index (VI), flow index and vascularization/flow index (VFI) were obtained before biopsy and compared with histopathologic results. We evaluated the predictive values for the detection of clinically significant PCa in the foci from different zones and the discrimination among various cancer grades. 3-D-PD-VOCAL discriminated malignant from benign foci, with cutoff values of 27.4% for VI, 38.2 for flow index and 8.6 for VFI. All parameters had higher areas under the curve in detecting lesions in the peripheral zone than in the transition zone (p < 0.05). VI and VFI had better diagnostic performance in detecting clinically significant PCa than flow index (p < 0.05). The area under the curve, sensitivity, specificity and accuracy in detecting clinically significant PCa were, for the VI and VFI respectively, 95% and 95%, 86% and 94%, 87% and 76%, and 87% and 85%. 3-D-PD-VOCAL initially demonstrated favorable performance in detecting PCa. Further, larger-sample studies based on prostatectomy specimens are needed to evaluate the exact usefulness of the technique. [ABSTRACT FROM AUTHOR]

We report a case of late type IIIb endoleak with Willis covered stent (WCS) developed 14 months after endovascular paraclinoid aneurysm repair. A 52-year-old woman presented with episodic headache, caused by a giant paraclinoid aneurysm. She underwent a successful 3.5 x 16mm WCS positioning to treat the aneurysm. Fourteen months later, the patient was admitted with the same symptoms. Digital subtraction angiography examination showed recurrence of the aneurysm, which was similar to the preoperative one. DynaCT (Siemens, Erlangen, Germany) indicated the intact of the metal structure of the stent without migration. Type IIIb endoleak (defect in the graft fabric) was confirmed with a whole aneurysm neck located in the middle part of the stent. The type IIIb endoleak was treated with another WCS (4.0 x 16mm). The immediate digital subtraction angiography imaging indicated that the endoleak disappeared and the aneurysm was completely occluded. Re-examination done 1 year after the second treatment showed a complete exclusion of the aneurysm sac. Type IIIb endoleaks can be safely treated by the endovascular positioning of another WCS. Continuous surveillance after endovascular paraclinoid aneurysm repair for intracranial aneurysms is warranted to make ensure the safety of WCS. [ABSTRACT FROM AUTHOR]

This work presents a method of designing an air heat sink with forced convection by topology optimization. Both pressure drop and heat transfer performances are evaluated. To reduce computational cost, a 2D two-layer model is first developed and implemented in COMSOL Multiphysics to represent three-dimension fully conjugate heat transfer modeling. It has been shown to be accurate in temperature field prediction and able to capture trends of pressure drop variation. Through a multi-stage optimization process, a non-conventional fin structure is created. The optimized structure is then manufactured and experimentally validated. Compared to a conventional straight channel heat sink, the topology optimized heat sink can achieve lower junction temperatures with the same pumping power or requires lower pumping powers for maintaining the same junction temperature. Furthermore, full 3D numerical analysis by ANSYS Fluent is performed to study the detailed characteristics of the topology optimized heat sink. It shows that the non-conventional layout of the fins introduces strong mixing effect, continuous boundary layer interruption and local high speeds, which all contribute to heat transfer enhancement. [ABSTRACT FROM AUTHOR]

Returning precious fissile materials containing 235U, obtained from regenerated uranium, to the nuclear fuel cycle is important for the production of sustainable nuclear energy. Herein, starting from the basic single cascade separation scheme, schemes for enriching regenerated uranium are developed to satisfy the requirements for low-enriched uranium with a commercial grade and several supplementary separation conditions to the greatest extent for different considerations involving the consumption of natural uranium, scale of separation cascade, and material recovery. Double- and triple-cascade schemes are derived from the consideration of improving the basic scheme by eliminating its drawbacks such as the contamination of the entire cascade by artificial nuclides. All schemes are optimized based on a Q-model cascade and are compared. The results demonstrate that the triple-cascade scheme exhibits a good separation performance and may be a good choice among the existing schemes. However, the concentration of 235U in this scheme exceeds the limitation specified by the international standard for handling fissile materials; therefore, this scheme requires further improvement. • Multi-cascade separation schemes are developed for regenerated uranium separation. • Conditions for concentrations, material recovery and closed fuel cycle are considered. • All schemes are optimized and compared based on their optimal results. • A triple cascade scheme with good separation performance is obtained. • The method of scheme development can be followed to develop new schemes. [ABSTRACT FROM AUTHOR]

The total flow of the optimal isotope separation cascade should be kept at a minimum to ensure economic viability. The concept of virtual components has proven useful in optimizing and designing cascades for multi-component isotope separation, but is only used in cases with an available analytical solution. Practical situations are complicated and resort to numerical simulations because there are no analytical solutions. Therefore, a generalization for numerical methods is required. A major difficulty in generalization is that mass conservation requires the concentration of a virtual component to be zero, which causes numerical problems. This paper proposes an approach to overcome this difficulty and develops a numerical method accordingly. The matched-R cascade is used as an example for numerical experiments to show that a cascade is solely determined by the choice of the two virtual components, and to demonstrate how the numerical method is applied to find the optimal cascade. [ABSTRACT FROM AUTHOR]

Abstract: The model Q-cascade is a useful tool for fast evaluation of the parameters of a separation cascade in the case of multi-isotope mixtures separation. Earlier the cascade key mass M is used as the optimization variable to search optimum parameters of a Q-cascade. A method is given here to determine the region for the valid values of the M parameter in the case of a Q-cascade with specified concentrations of a target component in its product and waste withdrawals. When a target isotope is contained in more than one component of a separation mixture, the idea for specifying the effective fractions of the target isotope in the withdrawals other than the concentrations of a target component is introduced and applied to the optimization of a Q-cascade. The applicability of the method in the determination of the valid values of the M parameter for specified effective fractions of a target isotope in cascade withdrawals is demonstrated. Examples of enrichment of cadmium and lead isotopes in Q-cascades are given to demonstrate the effectiveness of the suggested method. [Copyright &y& Elsevier]

Lead-free piezoelectric one-dimensional (1D) nanostructures have exhibited great potential in building biocompatible micro/nano-energy harvesters and self-powered smart sensors. However, their low piezoelectric coefficient still remains as the biggest obstacle for practical applications. In this work, an ultrahigh piezoelectric coefficient with calibrated d 33 from 400 pm V-1 to 814 pm V-1 is achieved in Li-doped (K,Na)NbO 3 (KNLN) lead-free piezoelectric nanorod arrays (NRAs). The giant enhancement on the piezoelectric performance of the KNLN nanorods can be attributed to the manipulation on the phase transition behavior together with the relaxation of strain. The Li+ dopants induce large NbO 6 octahedral distortion and result in the decreased phase transition temperature from orthorhombic (O) to tetragonal (T) phase, which leads to the construction of the O-T phase boundary at room temperature and improves the polarization performance of the products. The ultrahigh piezoelectric performance of the KNLN NRAs gives rise to the remarkably improved energy harvesting performance, which shows highly sensitive pressure sensing behaviors and can be utilized for monitoring the human-body motions. Giant piezoelectric coefficient d 33 up to 814 pm V-1 is achieved in lead-free (K,Na,Li)NbO 3 nanorod arrays by manipulating the orthorhombic-tetragonal phase boundary through A-site Li-doping. The KNLN nanorod arrays exhibit outstanding piezoelectric energy harvesting and pressure sensing performances and realize the self-powered monitoring of human body motions for smart analyzing of the human movement behaviors. [Display omitted] • Li-doped (K,Na)NbO 3 nanorod arrays were grown by hydrothermal process. • Giant piezoelectric coefficient d 33 ~ 814 pm V− 1 is achieved in KNLN nanorod arrays. • Orthorhombic-tetragonal phase boundary of KNLN nanorods is constructed at RT. • The nanogenerators exhibit outstanding energy harvesting and sensing performance. • Self-powered human-body-movements monitoring is realized by KNLN nanogenerators. [ABSTRACT FROM AUTHOR]

Flexible polyurethane (PU) foam is one of the most versatile materials, which has a widely range of applications. However, flexible PU foam it is easily ignitable and highly flammable. This study developed a kind of post-modification method to prepare inherent FR PU foam, which use β-CD as chain extender and introduce FR additive through a facile esterification between phosphoric acid and β-CD moiety in PU foams. The morphology and elasticity of PU still maintained after the modification of PU. β-CDs, as a bio-resources, can not only act as polyol carbon sources to promote carbon formation, but also crosslinked with phosphate ester and PU matrix through P–O–C bonds to form compact carbon layer during the combustion. This dense carbon layer effectively isolates the heat source of the flame, resulting in great improvement of combustion resistance. The time to ignition for 15% CD-H 3 PO 4 -PUF foam reached 152 s, which was over 10 times longer than that of pure PU foams. And the foam immediately self-extinguished when the flame was removed. The THR of 15% CD-H 3 PO 4 -PUF foam decreased by 70.43% compared to that of neat PU foam. The significant delay of TTI and reduction of THR can reduce the hazards of flame spread greatly. • A facile and green method to prepare inherent flame retardant (FR) polyurethane foam (PUF) has been developed. • β-Cyclodextrin (β-CD) act as both chain extender and reactive FR component in the FR PUF system. • Time to Ignition (TTI) of 15% CD-H3PO4-PUF is about 152 s, which is over 10 times longer than that of pure PUF. • The FR PUF also show significantly reduction of Total Heat Release (THR). Their THR could reduce 70.43% by neat PUF. [ABSTRACT FROM AUTHOR]

A series of pyridine and polypyridine-zinc complexes were synthesized, and their application in ε-caprolactone and l -lactide polymerization was studied. In ε-caprolactone polymerization, zinc complexes bearing 1,10-phenanthroline derivatives exhibited a higher polymerization rate than did diethyl zinc (2–10 times). In l -lactide polymerization, zinc complexes bearing 1,10-phenanthroline derivatives exhibited a considerably higher polymerization rate than did diethyl zinc (2–220 times). According to density functional theory results, the ortho -hydrogens of polypyridine ligand can co-activate the carbonyl group of monomers with zinc metal center to increase the catalytic activity of zinc catalysts. Image 1 • The polypyridne-zinc complexes were synthesized. • 1,10-Phenanthroline derivatives enhanced the catalytic activity of Zn complexes. • Hydrogens of polypyridine co-activate the carbonyl group of monomers. [ABSTRACT FROM AUTHOR]

• A similar fin pattern is found in a series of topology optimized heat sinks. • The sectional fins and semi-wavy layout promote heat transfer. • The proposed fin design outperforms five other traditional fin designs. This paper presents a new fin pattern for liquid-cooled microchannel heat sinks. It is derived from topology optimized heat sink structures reported in our previous paper. The new fin pattern is composed of two types of fins, oblique fin and trapezoidal fin, and they are arranged in a semi-wavy manner. Numerical simulation is implemented to examine its heat transfer and fluid flow characteristics in detail. A flow phenomenon that is similar to Dean's vortices is observed and results in enhanced flow mixing. The non-continuous fin pattern also avoids growth of thick boundary layers as they are initiated at the leading edges of each fin. Furthermore, size optimization based on the response surface method is performed to balance the heat transfer enhancement and pressure drop penalty. The new fin pattern is then compared with five other commonly used fin designs and shows the best performance in the studied flow range. [ABSTRACT FROM AUTHOR]

• A 2D thermofluid model is used to represent 3D model during topology optimization. • Various liquid-cooled microchannel heat sink fin structures are generated. • Topology optimized designs outperform size optimized straight channel heat sinks. • Their performance is verified by experimental tests and analysed by 3D simulation. Electronics cooling is always a critical challenge for its small profile and high heat flux. Various microchannel heat sinks have been proposed in literature to achieve reliable and energy efficient cooling effect. They are mainly different patterned fin shapes originated from researchers' experience. In this paper, we present the process of designing liquid-cooled microchannel heat sink fin geometries based on a numerical method, topology optimization. The optimization model is developed to find designs that satisfy heat transfer requirement with low pressure drop penalty. It is implemented based on a derived accurate 2D model with minimizing pressure drop as objective and average junction temperature as a constraint. Parameter study for different velocities and junction temperature constraints is performed. The optimized structures are then post processed under geometry constraints and analyzed by 3D CFD simulation. Size optimization is implemented on conventional straight channel heat sinks, which serve as the benchmark cases. Moreover, an experimental test loop is built to validate the 3D simulation of topology optimized heat sinks and straight channel heat sinks. The performance comparison shows that the topology optimized heat sinks could save up to 50.9% pumping power under the same thermal performance requirement. Detailed CFD analysis is then engaged to examine their thermohydraulic characteristics and reveal the reasons for their superior performance. [ABSTRACT FROM AUTHOR]

Efficient, flexible and self-healing electromagnetic interference (EMI) shielding materials are highly desirable and valuable for electromagnetic shielding industry. Furthermore, in order to achieve a commercial-grade EMI shielding effectiveness, a large amount of filler is required. Here, a kind of self-healing EMI shielding fabric was fabricated by preparing aligned carbon nanotube-poly (2-hydroxyethyl methacrylate) (CNT-PHEMA) non-woven fabric through magnetic-field-assisted electrospinning and cross-stacking aligned fabric layers. The unique aligned CNT stacking and porous structure enable that the materials can effectively absorbing EMI even at very low CNT loading amount (0.17 wt%). The host-guest interaction between β-cyclodextrin (β-CD) and adamantane (Ad) moieties not only made the fabric can adhere together automatically but also self-heal the scratch under 100% humidity environment. After the healing, the EMI shielding property can be restored 90.86 ± 3.90%. Image 1 [ABSTRACT FROM AUTHOR]

Abstract Organometallic perovskites have recently emerged as excellent solar cell materials for high power conversion efficiencies owed to their remarkable absorber characteristics, easy processing and low cost. Many efforts have been made by choosing appropriate additives to improve the power conversion efficiency and the stability. In this work, guanidine thiocyanate as the additive is introduced into the lead precursor solution to prepare perovskite films via two-step solution method. It is found that guanidine thiocyanate additive can notably improve the power conversion efficiency and the stability of MAPbI 3 perovskite solar cells due to the improvement of quality and crystal structure of perovskite films. After adding guanidine thiocyanate into lead precursor to prepare perovskite films, the high power conversion efficiency of solar cell is increased from 15.24% to 16.92%. The improvement mechanisms of power conversion efficiency and thermal stability of perovskite solar cells have been studied. Thiocyanate ion additive largely affects the immediate nucleation process of perovskite film in which provides the improved morphology of the perovskite film, while thiocyanate ions are absent from the resulting perovskite film. However, guanidine ion can substitute methylammonium ion in lattices of perovskite. The guanidine-ion additive is mainly responsible for the improvement of thermal stability of perovskite film and can increase the power conversion efficiency of solar cells. Graphical abstract Image 1 Highlights • An additive of GITC was first introduced into the precursor solution for improving the performances of MAPbI3 solar cells. • Thiocyanate ion additive largely affects the immediate nucleation process of perovskite film the quality of perovskite film. • Guanidine ion can substitute MA ion in lattices of perovskite film and improve the thermal stability of perovskite film. • More efficient carrier extraction and better charge-transfer ability in perovskite solar cells with 5% GITC additive. [ABSTRACT FROM AUTHOR]

Abstract: Design of an isotope separation cascade is often accompanied by minimizing the total flow in it to provide given concentrations of the target component in the product and the waste flows. This task is hard because the minimization deals with a multi-variable optimization of mixed integer and real type variables. In the present work, introducing a parameter M in the calculation of Q-cascades as the only optimization variable develops a new optimization approach. Numerical tests are carried out for separation of the isotopes 114Cd and 116Cd, respectively, and the results show that optimum cascades with minimum relative total flow for multicomponent isotope separation can be easily found with this new approach. [ABSTRACT FROM AUTHOR]

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection has caused a worldwide pandemic and poses a serious public health risk. It has been proven that lung ultrasound can be extremely valuable in the diagnosis and treatment of the disease, which could also minimize the number of exposed healthcare workers and equipment. Because healthcare workers in ultrasound departments are in close contact with patients who might be infected or virus carriers, it is extremely important that they be provided sufficient protection. Extremely aggressive protection should be avoided because it might lead to a lack of protection equipment for the hospital. Guidance on proper protection management should be provided in detail, for example, how to choose personal protective equipment, how to disinfect the environment. To address these problems, on behalf of the Chinese Ultrasound Doctors Association, Chinese PLA Professional Committee of Ultrasound in Medicine, Beijing Institute of Ultrasound in Medicine and Chinese Research Hospital Association Ultrasound Professional Committee, the authors have summarized the recommendations for effective protection according to existing hygienic standards, their experience and available literature. After the recommendations were completed, two online conferences were held on January 31, 2020 and February 7, 2020, at which the recommendations were discussed in detail. A modified version of the work was circulated and finally approved by all authors, and is the present Chinese Expert Consensus on Protection for Ultrasound Healthcare Workers against COVID-19. [ABSTRACT FROM AUTHOR]

Hypoplastic left heart syndrome (HLHS) is a rare, but exceptionally serious, congenital heart defect. We aimed to explore the best-fitted Z-score models for individual chamber dimension and to draw a comparison between fetuses with HLHS and the normal Chinese cohort. We made measurements of 1674 healthy fetuses and 79 fetuses with HLHS, undertaking echocardiography. Normal fetal cardiovascular Z-score formulae were established by curve-fitting with 5 algorithmic functions and weighted regression of absolute residuals. Classic linear models were fitted for left ventricular diameter against gestational age, and log-transformed linear-power models-were statistically better for left ventricular length, diameter of left atrium and ascending aorta. Fetuses with HLHS manifested significantly lower Z-score means (≤3.5) for these 4 parameters and the vast majority (∼90%) lay beyond -2. Overall, cardiovascular Z-score equations were reliably constructed in a larger Chinese cohort, and their application should benefit evaluation and diagnosis of HLHS. [ABSTRACT FROM AUTHOR]

Highlights • Wind tunnel experiments are conducted to validate the CFD models. • By bending the fin to form a guiding channel, the thermal performance is enhanced. • The fin is designed using topology optimisation to minimise the pressure drop. • The two novel fin designs perform better than the baseline fin. Abstract As the air-side heat transfer is controlling the efficiency of fin and tube heat exchangers (FTHX), the thermal enhancement of FTHX relies more on the air-side. A theoretical model of the baseline FTHX is built using ANSYS Fluent which is then validated by wind tunnel experiments. After analysing the simulation results of the baseline FTHX, two novel air-side fin configurations are proposed. The first design can guide more airflow to the back of the tubes to mitigate wake zones. For the second design, topology optimisation is used to significantly increase the heat transfer area at the air-side with minimised pressure drop penalty. To further improve the two designs, parametric studies are conducted through which optimal design parameters are obtained. Comparing with the baseline FTHX, the optimal guiding channel fin design and topology optimisation fin design can dissipate 8.5% and 7.0% more heat respectively, or consume 41.4% and 33.3% less fan power respectively. As such, the proposed enhanced air-side fin designs are promising candidates for improving the efficiency of FTHXs. [ABSTRACT FROM AUTHOR]

Due to increasing application of 210 Po/ 210 Pb in studying particle dynamics, a consistent procedure and calculation to derive accurate and precise result of 210 Po and 210 Pb in seawater should be proposed in the framework of intercalibration by GEOTRACES. The associated uncertainty of radioactivity, which is a significant component of data report, plays a vital role in intercomparison and should be well evaluated. Although measurement uncertainty of laboratory result was well defined in ISO standards and IAEA technical documents, the decay/ingrowth uncertainty correction from laboratory result to in-situ result was less studied. It was demonstrated that the relative uncertainty of in-situ 210 Pb activity was independent of elapsed time and equal to relative uncertainty of laboratory measuring 210 Po activity at second spontaneous deposition date. The relative uncertainty of in-situ 210 Po activity decreases with in-situ activity ratio of 210 Po to 210 Pb and increases with elapsed time between sampling date and separation date, relative uncertainty of laboratory measuring 210 Po activity at first spontaneous deposition date and relative uncertainty of in-situ 210 Pb activity. It was more important to improve precision of 210 Po at first spontaneous deposition date than that of 210 Po at second spontaneous deposition date. To obtain a desirable relative uncertainty of in-situ 210 Po activity, the maximum allowing elapsed time for 210 Po, which was important for sampling strategy making and quality assurance, was calculated by in-situ activity ratio of 210 Po to 210 Pb and precision of analytical method for 210 Po. The methodology of decay/ingrowth uncertainty correction could also be applied for other radionuclide pairs ( 234 Th/ 238 U, 90 Y/ 90 Sr, 210 Bi/ 210 Pb), sample matrixes (aerosols), and disciplines. [ABSTRACT FROM AUTHOR]

Abstract: In this article, poly(ɛ-caprolactone)–poly(ethylene glycol)–poly(ɛ-caprolactone) (PCL–PEG–PCL, PCEC) nanoparticles were successfully prepared for honokiol delivery in vitro. Blank or honokiol loaded PCL–PEG–PCL nanoparticles were prepared in moderate condition by solvent diffusion method without using any surfactants. The prepared blank PCL–PEG–PCL nanoparticles are mono-dispersed and smaller than 200nm. The particle size increased with increase in polymer concentration and oil–water (O/W) ratio. The prepared PCL–PEG–PCL nanoparticles (40mg/mL, ca. 106nm) did not induce hemolysis in vitro. And the 50% inhibiting concentration (IC50) of it (48h) on HEK293 cells was higher than 5mg/mL. Honokiol could be efficiently loaded into PCL–PEG–PCL nanoparticles and released from these nanoparticles in an extended period in vitro. After honokiol (HK) was entrapped into PCL–PEG–PCL nanoparticles, the particle size increased with the increase in HK/PCEC mass ratio in feed, and the encapsulated honokiol retained potent anticancer activity in vitro. The PCL–PEG–PCL nanoparticle was suitable for honokiol delivery, and such honokiol loaded PCL–PEG–PCL nanoparticle was a novel honokiol formulation. [Copyright &y& Elsevier]

Abstract: Self-assembled polymeric micelles are widely applied in drug delivery system (DDS). In this study, honokiol (HK) loaded micelles were prepared from biodegradable poly(ɛ-caprolactone)-poly(ethylene glycol)-poly(ɛ-caprolactone) (PCEC) copolymers. Micelles were prepared by self-assembly of triblock copolymer PCEC in distilled water triggered by its amphiphilic character without any organic solvent. Drug loading and encapsulation efficiency were determined by adjusting the weight ratio of HK and PCEC. The particle size and zeta potential distribution of obtained micelles were determined using Malvern laser particle sizer, and spherical geometry were observed on atomic force microscope (AFM). Otherwise, the thermo-sensitivity of honokiol-loaded micelles was monitored. And the cytotoxicity results of drug loaded micelles showed that the encapsulated honokiol remained potent antitumor effect. Moreover, in vitro release profile demonstrated a significant difference between rapid release of free honokiol and much slower and sustained release of HK-loaded micelles. These results suggested that we have successfully prepared honokiol-loaded micelles in an improved method which is safer and more efficient. The prepared micelles might be potential carriers for honokiol delivery in cancer chemotherapy. [Copyright &y& Elsevier]

Abstract: We previously reported that gambogic acid (GA), a natural product, was an effective telomerase inhibitor by repressing hTERT promoter. In this study, posttranscriptional regulation of the telomerase hTERT by GA was investigated in BGC-823 human gastric carcinoma cells. The telomerase activity was detected by PCR-TRAP assay. RT-PCR assay and Western blot were performed to examine the repression of telomerase hTERT and c-Myc after GA or c-Myc-specific siRNA treatment. The results indicated that GA repressed telomerase activity and hTERT transcriptional activity via down-regulation of c-Myc expression in BGC-823 human gastric carcinoma cells. We further observed that hTERT transcriptional activity was not completely blocked by c-Myc-specific siRNA, suggesting that additional factors are involved in the repression of telomerase activity. The results of Western blot and immunoprecipitation assay revealed that GA inhibits the phosphorylation of Akt. The further results also confirmed that celecoxib, an inhibitor of Akt phosphorylation, could significantly repressed telomerase activity alone and enhance the repression of telomerase activity combined with GA. These data suggested that GA inhibits the posttranslational modification of hTERT by inhibiting the phosphorylation of Akt. Collectively, we suggest that GA represses telomerase activity not only by repressing hTERT transcriptional activity via c-Myc but also by posttranslational modification of hTERT via Akt. [Copyright &y& Elsevier]