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This study aimed to develop predictive models based on conventional magnetic resonance imaging (cMRI) and radiomics features for predicting human epidermal growth factor receptor 2 (HER2) status of breast cancer (BC) and compare their performance. A total of 287 patients with invasive BC in our hospital were retrospectively analyzed. All patients underwent preoperative breast MRI consisting of fat-suppressed T2-weighted imaging, axial dynamic contrast-enhanced MRI, and diffusion-weighted imaging sequences. From these sequences, radiomics features were derived. Three distinct models were established utilizing cMRI features, radiomics features, and a comprehensive model that amalgamated both. The predictive capabilities of these models were assessed using the receiver operating characteristic curve analysis. The comparative performance was then determined through the DeLong test and net reclassification improvement (NRI). In a randomized split, the 287 patients with BC were allotted to either training (234; 46 HER2-zero, 107 HER2-low, 81 HER2-positive) or test (53; 8 HER2-zero, 27 HER2-low, 18 HER2-positive) at an 8:2 ratio. The mean area under the curve (AUCs) for cMRI, radiomics, and comprehensive models predicting HER2 status were 0.705, 0.819, and 0.859 in training set and 0.639, 0.797, and 0.842 in test set, respectively. DeLong's test indicated that the combined model's AUC surpassed the radiomics model significantly (p < 0.05). NRI analysis verified superiority of the combined model over the radiomics for BC HER2 prediction (NRI 25.0) in the test set. The comprehensive model based on the combination of cMRI and radiomics features outperformed the single radiomics model in noninvasively predicting the three-tiered HER2 status in patients with BC. [ABSTRACT FROM AUTHOR]

Strong absorption and large bandwidth are two contributors to material's electromagnetic wave absorbing performance. While spinel ferrite materials have garnered extensive attention in the realm of microwave absorption, their relatively low conductivity remains a practical challenge. In this work, NiCo 2-x Fe x O 4 (x = 0, 0.04, 0.06 and 0.08) precursor was prepared by hydrothermal and after-sintered method. It was found that Fe doping exhibit excellent EM absorption properties. Specially, when the Fe content is 0.08, the maximum reflection loss −48.90 dB at 15.40 GHz and the maximum effective bandwidth 4.20 GHz are achieved. More importantly, the absorption frequency can be broadened from Ku to C band even to S band with proper adjusting Fe content. Doping with Fe enhances conduction loss and make a significant contribution to dielectric loss, as a result, the impedance matching degree of the Fe-NiCo 2 O 4 composite is influenced by the synergistic effect of its dielectric and magnetic properties. This work provides a simple way for enhancing the microwave absorption capabilities of ferrite materials and provides insight into understanding conduction loss in microwave absorption. [ABSTRACT FROM AUTHOR]

The tuned mass damper (TMD) has been used in machining processes for reducing forced vibration, suppressing chatter, and improving machined surface quality. In micro-milling process, the tiny size of the cutting tool-tip and the high rotating speed bring challenges in implementing the TMD. Besides, the TMD needs to have two degrees-of-freedom (DOFs) for reducing vibrations of micro-mill in two orthogonal directions. This paper presents the chatter suppression for micro-milling by attaching a two-DOF TMD to the tool shank and rotates with the cutting tool. The frequency response function (FRF) at the tip of the micro-mill clamped by an aerostatic spindle is predicted using receptance coupling analysis. A two-DOF TMD is designed via graphical approach based on the FRF result at the tool-tip. The natural frequencies and damping ratio of the TMD are optimized under different spindle speeds in order to enhance the cutting stability. The chatter stability of micro-milling is predicted considering the gyroscopic and centrifugal effects of the TMD structure. Modal tests and micro-milling experiments are conducted to validate the effect of the TMD on chatter stability. The results show that the TMD is able to improve the critical depth of cut by 13 folds, and satisfy the compact design requirement for micro-milling. • Shank-mounted TMD satisfies the specific geometric requirement in micro-milling. • Design of TMD using graphical approach based on synthesized FRFs of substructures. • The centrifugal and gyroscopic effects of TMD on chatter stability are studied. • Chatter-free axial depth of micro-milling operation is enhanced by 13 folds. [ABSTRACT FROM AUTHOR]

The energy harvester has been employed to transform mechanical vibration into electrical power in the field of road transportation. An electromagnetic energy harvester for bicycle application to recycle low-frequency vibration is proposed. The input of up-down motion is transformed into bidirectional rotation by the transmission part, and then translated into unidirectional rotation by the rotating motion rectifier. The rectifier outputs rotation to the generator, and the electrical energy generated can be stored in super capacity at the charging mode or light up the LED at the discharging mode. Lab experiments are conducted to test the proposed harvester on Instron servo-hydraulic machine. A power of 0.491 W and a total efficiency of 52.8% are achieved with sinusoidal displacement inputs from 1.0 Hz to 2.5 Hz and external resistors from 50 Ω to 200 Ω. Field tests of applying the harvester onto the bicycle are carried out and a power of 0.313 W is obtained when riding through the speed bump. Above tests demonstrate potential applications of the harvester in self-powered devices. • A harvester for low-frequency vibration is proposed and applied onto the bicycle. • Mechanism of the harvester is designed by ball screw and rotating motion rectifier. • Engagement and disengagement periods of the rectifier are investigated. • The harvester can achieve a power of 0.491 W and a total efficiency of 52.8%. [ABSTRACT FROM AUTHOR]

Prolonged isolated thrombocytopenia (PT) is a severe complication in patients after allogeneic hematopoietic stem cell transplantation (allo-HSCT). Whether the megakaryoctic potential of hematopoietic stem cells (HSCs) in bone marrow is intact and what factors drive the pathological process of PT remain elusive. A retrospective study in patients (n = 285) receiving HSCT revealed that the occurrence of PT was approximately 8% and the number of platelets and megakaryocytes in PT patients is much lower compared with control subjects. To test whether the deficiency of thrombopoiesis was caused by the activities of HSCs, the megakaryocytic differentiation potential of HSCs before or after transplantation was assessed. Interestingly, a substantial decrease of megakaryocytic differentiation was observed 2 weeks after transplantation of HSCs in all of the allo-HSCT recipients. However, 4 weeks after transplantation, the ability of HSCs to generate CD41 + CD42b + megakaryocytes in successful platelet engraftment patients recovered to the same level as those of HSCs before implantation. In contrast, HSCs derived from PT patients throughout the postimplantation period exhibited poor survival and failed to differentiate properly. A protein array analysis demonstrated that multiple inflammation-associated cytokines were elevated in allo-HSCT recipients with PT. Among them, insulin-like growth factor–binding protein 1 and regulated on activation, normal T cell expressed and secreted were found to significantly suppress the proliferation and megakaryocytic differentiation of HSCs in vitro. Our results suggested that the occurrence of PT may be attributed, at least partially, to the damage to HSC function caused by inflammation-associated cytokines after HSCT. These findings shed light on the mechanism underlying HSC megakaryocytic differentiation in PT patients and may provide potential new strategies for treating PT patients after HSCT. [ABSTRACT FROM AUTHOR]

Passive control has been effective in damping the machining vibration of thin-walled parts. However, physical addition onto the part causes the dynamics change and limits the engagement of cutting tool, especially in the application of multi-axis machining. Utilizing the non-contact eddy current damping, a two-degree-of-freedom apparatus is designed after experimental investigation into the magnet combination, magnetic flux density and magnetic flux mode on damping behaviors on a specifically designed platform. The apparatus is set up by mounting on the stationary spindle head of a five-axis CNC machine tool. The included neodymium magnets, and then the induced eddy current damping force are able to follow the feeding cutter through the control of two servo motors, keeping out of touch with the thin-walled part to be damped. As the damping force is able to resist the vibration of the machining point induced by the cutting force directly, it allows the design with less volume and mass (i.e. magnets and conductors). In the end, hammer tests are performed to verify the additional damping ratio imposed by the apparatus. Three-axis milling tests of a thin-walled frame are carried out to validate the damping of the apparatus, and five-axis milling tests of thin-walled blade type part are conducted to demonstrate its controllable damping and adaptability to complex tool path. [ABSTRACT FROM AUTHOR]

Background: We recently reported that an S140G mutation in human KCNQ1, an alpha subunit of potassium channels, was involved in the pathogenesis of familial atrial fibrillation (AF), but it is not clear whether the mutation is associated with other cardiac arrhythmias.Objective: The purpose of this study was to further explore the association of the KCNQ1 S140G mutation with cardiac arrhythmias.Methods: We produced a transgenic mouse model with myocardium-specific expression of the human KCNQ1 S140G mutation under the control of an alpha-cardiac myosin heavy chain promoter by standard transgenic procedure and evaluated the relationship between the KCNQ1 mutation and its phenotypes in a human family.Results: Four lines of transgenic mice were established with a high level of human KCNQ1 S140G expression in the heart. Frequent episodes of first-, second-, advanced-, or third-degree atrioventricular block (AVB) occurred in at least 65% of transgenic descendants from the four lines. However, none of the five wild-type transgenic lines presented with AVBs. HMR1556, a KCNQ1-specific blocker, can terminate the AVBs. With the exception of at most three AF individuals, at least 13 AF patients were found to show obviously slow ventricular response, which may be one manifestation of AVBs. Interestingly, AF was not detected in these transgenic mice.Conclusion: The results suggest that human KCNQ1 S140G is also likely to be a causative mutation responsible for AVBs. The transgenic mouse model is a potential tool to explore mechanisms of AVBs. [ABSTRACT FROM AUTHOR]

• A coaxial mechanical motion rectifier with function of increasing transmission ratio. • A variable inertia flywheel for extending overrunning phase. • Dynamics modeling of mechanical motion rectifier considering overrunning phase. • Establishment of angular velocity of the generator with variable inertia flywheel. • Max efficiency of 51.54% in lab and max power of 3.35 W in ocean. The wave energy harvester has been employed to power marine devices. For the wave energy harvester based on mechanical motion rectifier, the output power and efficiency are limited due to low inertia-damping ratio and perpendicular motion transformation. A coaxial mechanical motion rectifier with the function of increasing transmission ratio is designed based on a planetary gear train and four one-way clutches, and the input and output shafts are arranged coaxially. A variable inertia flywheel is incorporated in the wave energy harvester to extend the overrunning phase by slowing down the velocity attenuation of the generator. The wheel in variable inertia flywheel is reduced to four cantilever sliders to decrease the starting torque. The dynamics model of the wave energy harvester considering the meshing and overrunning phases is investigated due to the introduction of variable inertia flywheel. The input force and output voltage are simulated with sinusoidal displacement input after obtaining the angular velocity of generator with variable inertia flywheel. A maximum efficiency of 51.54% and average output power of 1.17 W on Instron machine are achieved, while a maximum output power of 3.35 W in ocean tests is obtained. The experiments verify that the design of coaxial mechanical motion rectifier and variable inertia flywheel is beneficial to improving the output power and efficiency. [ABSTRACT FROM AUTHOR]

SnO 2 @C@MnO 2 hierarchical hollow hybrid nanospheres have been obtained by coating the MnO 2 nanosheet-based hierarchical shell on SnO 2 @C hollow nanospheres via a redox method. The hierarchical hollow hybrid nanospheres are composed of the SnO 2 internal layer with hollow nanostructures, the carbon interlayer and the MnO 2 hierarchical nanostructured external layer built from two dimensional nanosheets. SnO 2 @C@MnO 2 nanomaterials exhibit a large initial discharge capacity (1378 mAhg −1 ), extraordinary cyclic stability (644.5 mAhg −1 after 200 cycles) and rate capability as Li-ion battery anodes. The excellent properties may benefit from the rational design of hierarchical hollow hybrid nanostructures and the synergistic effects between the three layers of SnO 2 , carbon and MnO 2 . [ABSTRACT FROM AUTHOR]

• The 3D porous rGO/Ti 3 C 2 T x /TiO 2 multi-interfaces composite is prepared via a one-step hydrothermal. • The composite achieves a good RL min of −37.31 dB and a broadened EAB of 6.45 GHz. • Multi-interfaces inside the composite make significant contributions to polarization loss and the optimized impedance matching. Multi-layer 2D material assemblies introduce numerous interfaces that would improve microwave absorbing. Here, a 3D porous rGO/Ti 3 C 2 T x /TiO 2 heterostructure was prepared using a one-step hydrothermal synthesis. Due to the presence of the 2D/2D van der Waals heterojunction in rGO/Ti 3 C 2 T x featuring face-to-face contacts, and the 2D/0D heterojunctions in Ti 3 C 2 T x /TiO 2 , the interfacial polarization is optimized. The minimum reflection loss (RL min) achieves −37.31 dB, and the effective absorption bandwidth (EAB) extends to 6.45 GHz (with<−10 dB). These results not only shed light on understanding and enhancement of interfacial effects, but also provides an appealing mode for the implementation of heterogeneous interfacial engineering using tailored 2D hierarchical structures. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract: A new-type nonlinear tuned mass damper (TMD) containing an additional element of elastic support dry friction compared with the common linear TMD is proposed to suppress machining chatter. The design and tuning process of this nonlinear TMD have used a combination of analytical modeling with experimentally measured frequency response function (FRF) of the machining system. Theoretical studies and experimental results show that the proposed nonlinear TMD can remarkably improve the machining stability by effectively suppressing the magnitude of the real part of the FRF of the damped machining system. [Copyright &y& Elsevier]

Multi-yolk-shell SnCo@N-doped carbon nanocages with controllable carbon shell thickness are well fabricated by a novel approach. The multi-yolk-shell SnCo@N-doped carbon nanocages form an enough void volume to compensate the volume expansion of SnCo nanoparticles during Li + insertion. To optimize the electrochemical properties, SnCo@N-doped carbon nanocages with controllable carbon shell thickness can be tailored by coating polydopamine (PDA) with various thicknesses on CoSn(OH) 6 hollow nanocubes in the second step of the synthesis process. Multi-yolk-shell SnCo@N-doped carbon nanocages with the optimized shell thickness exhibit a high initial discharge capacity (1025 mAhg −1 ) and remarkable cyclic stability (611 mAhg −1 after 100 cycles) as Li-ion batteries anode. This work may open a wonderful way for the rational design of alloy@carbon composites with tailorable structures for next-generation anode nanomaterials in Li-ion battery. [ABSTRACT FROM AUTHOR]

P. lobata and P. thomsonii are medicinal plants with similar pharmacological functions but different therapeutic effects. A novel method is presented herein to investigate metabolites in terms of their distribution and qualification, quantification is necessary to elucidate the different therapeutic effects of the two Puerariae species. The aim of the present study was to perform spatially resolved metabolomics combined with bioactivity analyses to systematically compare the metabolite differences in P. lobata and P. thomsonii by distribution, qualification, quantification, and biological activity to evaluate their pharmacological properties. Air flow-assisted desorption electrospray ionization–mass spectrometry imaging (AFADESI-MSI) was performed to characterize the differences in the metabolite distributions of P. lobata and P. thomsonii. Further qualitative and quantitative analyses of the differential metabolites were performed using liquid chromatography–mass spectrometry (LC-MS). Biological activities correlated with the differences in the metabolites were validated by MTT assays. Some metabolites showed complementary distributions of the phloem and xylem in the two species, saccharide, vitamin, and inosine levels were higher in the phloem of P. thomsonii but higher in the xylem of P. lobata. The 3′-hydroxyl puerarin level was higher in the xylem of P. thomsonii but higher in the phloem of P. lobata. Qualitative and quantitative analyses of the metabolites revealed a total of 52 key differential metabolites. MTT assays showed that daidzein, daidzin, puerarin, ononin, genistin, formononetin, 3′-hydroxy puerarin, 3′-methoxy puerarin, mirificin, and 3′-methoxy daidzin exerted protective effects on H9c2 cells against hypoxia/reoxygenation injury. P. lobata extracts exhibited a significantly better protective efficacy than P. thomsonii extracts. In this study, AFADESI-MSI combined with LC-MS and biological activities comprehensively elucidated metabolite differences in the distribution, qualification, quantification, and pharmacological properties of P. lobata and P. thomsonii. The results of this study could provide a novel strategy for species identification and quality assessment of similar Chinese herbal medicines. [Display omitted] • AFADESI-MSI enables wide-coverage detection of massive metabolites in Puerariae. • The heterogeneous spatial features of metabolites in Pueraria were imaged. • Distinguishing two Puerariae species with AFADESI-MSI and biological activities. [ABSTRACT FROM AUTHOR]

Placental fetal macrophages (fMacs) are the only immune cells on the fetal side of the placental barrier. Mouse models have not been used to test their function because they have previously been found to have distinct cellular origins and functions in mice and humans. Here, we test the ontogeny of mouse placental fMacs. Using a new Hoxa13Cre allele that labels all placental endothelial cells (ECs), we demonstrate that mouse placenta fMacs do not arise from placental endothelium. Instead, lineage tracing studies using Tie2-Cre and Cx3cr1CreERT2 alleles demonstrate that mouse placental fMacs arise from yolk sac endothelium. Administration of blocking antibodies against CSF1R at E6.5 and E7.5 results in depletion of placental fMacs throughout pregnancy, and this suggests a yolk sac origin, similar to that in human fMacs. This Matters Arising paper is in response to Liang et al., published in Developmental Cell. A response by Liang and Liu is published in this issue. [Display omitted] • New Hoxa13Cre knockin mice specifically target all placenta endothelial cells • Mouse placenta fetal macrophages do not arise from placental endothelium • Mouse placenta fetal macrophages are tissue resident macrophages from the yolk sac • Mouse placental fetal macrophages share a common origin as human Hofbauer cells In this Matters Arising article, Chen et al. use a newly generated Hoxa13Cre allele to show that mouse placenta fetal macrophages (fMacs) originate from placenta endothelium, differing from the origin described in the study conducted by Liang et al. They demonstrate that fMacs are yolk sac with similar origin to that of human Hofbauer cells. [ABSTRACT FROM AUTHOR]

This paper proposes a mechanism for the inductive effect of quinoline on coke formation during the catalytic cracking of o-xylene. Quinoline preferentially adsorbs on the acidic sites to induce coke formation and promote the conversion of o-xylene via electrophilic substitutions and hydrogen transfer reactions. The presence of naphthyl-quinolines and benzyl-quinolines in soluble coke identified by electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry and the characterization of two types of nitrogen species in coke by XPS both confirm that the mechanism is reasonable. Basic nitrogen compounds poison the acidic sites of catalysts and induce the coke formation from aromatics. [ABSTRACT FROM AUTHOR]

Ginseng rusty root (GRR) is a commonly occurring disease that affects the continuous farming and economic value of mountain cultivated ginseng (MCG). Previous studies have demonstrated a generally smaller level of total ginsenoside in GRR tissue, but differences in individual ginsenosides or changes between rusty and healthy MCG with a higher age have not been investigated. This research aimed to identify differences in the chemical components in the roots of rusty compared with healthy MCG harvested at 20-years of age. Differences between rusty and healthy MCG roots in individual ginsenosides were evaluated using a non-targeted metabonomic-based ultrahigh-performance liquid chromatography quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS) technique. Chemical markers and the principal constituents were then quantified by ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). Furthermore, total ginsenosides, total polysaccharides, and the elemental composition were evaluated separately using spectrophotometry and inductively coupled plasma optical emission spectrometer (ICP-OES). There was no significant difference in the levels of total ginsenosides or total polysaccharides between the rusty and healthy groups. However, the concentrations of pivotal individual ginsenosides, including ginsenoside Rc, ginsenoside Ro, and ginsenoside Rd were significantly lower in the rusty group. In addition, concentrations of Fe and Al were higher in the rusty group compared with the healthy group. The results suggest that GRR affects the synthesis of ginsenosides of 20-year-old MCG, which further establishes reference data and the basis for exploration of the mechanisms causing metabolic changes in ginseng resulting from GRR. [Display omitted] [ABSTRACT FROM AUTHOR]