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Key Clinical Message: The entrapment of the left renal vein (LRV) may contribute to changes in hemodynamics within kidney and could also be associated with IgA nephropathy (IgAN). Although the relationship between the nutcracker phenomenon and IgAN has not yet been elucidated, it is speculated that this patient's refractory hypertension is a combined effect of nutcracker syndrome (NCS) and IgAN. [ABSTRACT FROM AUTHOR]

Perovskite quantum dots (PQDs) show high potential for new‐generation light‐emitting diodes (LEDs) due to their outstanding optoelectronic properties. Even though the red PQD‐LEDs can be realized through mixing halide in the PQDs to tune their spectroscopies, the PQDs may suffer from phase separation under a high electric field, predominantly affecting LED applications. Herein, a ligand‐pinning‐assisted approach is reported to tune the spectroscopies of CsPbI3 PQDs, in which vinyl phosphonic acid (VPA) is applied as function ligands to regulate the nucleation and growth of PQDs during the synthesis. Systematically experimental studies and theoretical calculations are conducted to comprehensively understand the functions of the VPA ligands during the PQD synthesis, which reveals that the VPA ligands with high binding energy with Pb2+ cations could firmly anchor on the surface matrix of PQDs without desorption, regulating the growth of PQDs and thus resulting in tunable spectroscopies being realized. Meanwhile, VPA could also renovate the defective surface matrix of PQDs, substantially diminishing trap‐induced nonradiative recombination. Consequently, red PQD‐LEDs deliver a high external quantum efficiency of 22.83%, which is significantly improved compared with the control devices. This work provides a new avenue to tune the spectroscopies of PQDs toward high‐performing LEDs. [ABSTRACT FROM AUTHOR]

The properties of the emerging phosphochalcogenide compounds can be tuned by temperature, pressure, and the chemical composition characterized by the compound entropy. However, it is unknown how the entropy of such a compound affects its structural stability and material properties when a state variable changes. In this work, a new layered high‐entropy phosphoselenide compound (MnFeCuCdIn)PSe3 (denoted MPSe3) is prepared and its structural evolution and property changes are studied at pressures up to ≈60 GPa. It is found that the compound undergoes two isostructural changes at ≈10 and 20 GPa, a structural change forming a high‐coordination phase in ≈32–35 GPa, a semiconductor‐to‐metal transition in ≈28–30 GPa at room temperature, and a metal‐to‐superconductor transition in ≈2.5–4.9 K at a pressure from ≈43 to 58 GPa. Combining data from prior studies, it is further found that for the MPSe3‐type medium/high‐entropy compounds, there exists a linear relationship between the structural transition pressure and the cation mixing entropy, and an inverse nearly linear relationship between the superconducting critical temperature and the cation mixing entropy, with the latter due primarily to the decrease in the Debye temperature. These findings will have great importance for developing new complex materials using the evolving entropy engineering. [ABSTRACT FROM AUTHOR]

Herein, (14,14,14)‐graphyne (GY) supported by silicon substrate is chosen to be the research object. The results demonstrate that the increasing distance between substrate and supported materials (dsub‐sup) results in the enhancement of thermal conductivity (TC) of supported GY, and the TC of supported GY is even higher than that of free‐standing GY when dsub‐sup exceeds a certain value, which means substrate plays an abnormal promoting role in the thermal transport in supported materials (SM). This phenomenon breaks the traditional cognition that the increasing dsub‐sup can only lead to the TC of SM approaching that of free‐standing model. The related mechanism can be seen as the combined impact of weak interaction of long‐dsub‐sup substrate and tensile effect led by lattice mismatch between substrate and GY. Combining with phonon analysis, it can be observed that the influence of substrate shows a closer relationship with phonon scattering, i.e., the anharmonicity, especially the anharmonicity of out‐of‐plane direction. The anomalous promoting effect of long‐dsub‐sup can be also attributed to the weaker scattering of out‐of‐plane phonon, especially the reduced four‐order phonon scattering. This research provides a new idea to suppress the negative effect of substrate on heat dissipation in electronic devices. [ABSTRACT FROM AUTHOR]

CsPbI3 perovskite receives tremendous attention for photovoltaic applications due to its ideal band gap and good thermal stability. However, CsPbI3 perovskite solar cells (PSCs) significantly suffer from photovoltage deficits because of serious interfacial energy losses within the PSCs, which to a large extent affects the photovoltaic performance of PSCs. Herein, a dipolar chemical bridge (DCB) is constructed between the perovskite and TiO2 layers to lower interfacial energy losses and thus improve the charge extraction of PSCs. The results reveal that the DCB could form a beneficial interfacial dipole between the perovskite and TiO2 layers, which could optimize the interfacial energetics of perovskite/TiO2 layers and thus improve the energy level alignment within the PSCs. Meanwhile, the constructed DCB could also simultaneously passivate the surface defects of perovskite and TiO2 layers, greatly lowering interfacial recombination. Consequently, the photovoltage deficit of CsPbI3 PSCs is largely reduced, leading to a record efficiency of 21.86 % being realized. Meanwhile, the operation stability of PSCs is also largely improved due to the high‐quality perovskite films with released interfacial tensile strain being obtained after forming the DCB within the PSCs. [ABSTRACT FROM AUTHOR]

The heart primarily derives its energy through lipid oxidation. In cardiomyocytes, lipids are stored in lipid droplets (LDs) and are utilized in mitochondria, although the structural and functional connections between these two organelles remain largely unknown. In this study, visible evidence have presented indicating that a complex is formed at the mitochondria‐LD membrane contact (MLC) site, involving mitochondrion‐localized Mfn2 and LD‐localized Hsc70. This complex serves to tether mitochondria to LDs, facilitating the transfer of fatty acids (FAs) from LDs to mitochondria for β‐oxidation. Reduction of Mfn2 induced by lipid overload inhibits MLC, hinders FA transfer, and results in lipid accumulation. Restoring Mfn2 reinstates MLC, alleviating myocardial lipotoxicity under lipid overload conditions both in‐vivo and in‐vitro. Additionally, prolonged lipid overload induces Mfn2 degradation through the ubiquitin‐proteasome pathway, following Mfn2 acetylation at the K243 site. This leads to the transition from adaptive lipid utilization to maladaptive lipotoxicity. The experimental findings are supported by clinical data from patients with obesity and age‐matched non‐obese individuals. These translational results make a significant contribution to the molecular understanding of MLC in the heart, and offer new insights into its role in myocardial lipotoxicity. [ABSTRACT FROM AUTHOR]

Summary: As a frequently consumed beverage worldwide, tea is rich in naturally important bioactive metabolites. Combining genetic, metabolomic and biochemical methodologies, here, we present a comprehensive study to dissect the chemical diversity in tea plant. A total of 2837 metabolites were identified at high‐resolution with 1098 of them being structurally annotated and 63 of them were structurally identified. Metabolite‐based genome‐wide association mapping identified 6199 and 7823 metabolic quantitative trait loci (mQTL) for 971 and 1254 compounds in young leaves (YL) and the third leaves (TL), respectively. The major mQTL (i.e., P < 1.05 × 10−5, and phenotypic variation explained (PVE) > 25%) were further interrogated. Through extensive annotation of the tea metabolome as well as network‐based analysis, this study broadens the understanding of tea metabolism and lays a solid foundation for revealing the natural variations in the chemical composition of the tea plant. Interestingly, we found that galloylations, rather than hydroxylations or glycosylations, were the largest class of conversions within the tea metabolome. The prevalence of galloylations in tea is unusual, as hydroxylations and glycosylations are typically the most prominent conversions of plant specialized metabolism. The biosynthetic pathway of flavonoids, which are one of the most featured metabolites in tea plant, was further refined with the identified metabolites. And we demonstrated the further mining and interpretation of our GWAS results by verifying two identified mQTL (including functional candidate genes CsUGTa, CsUGTb, and CsCCoAOMT) and completing the flavonoid biosynthetic pathway of the tea plant. [ABSTRACT FROM AUTHOR]

Cesium lead triiodide (CsPbI3) perovskite receives tremendous attention for photovoltaic applications, owing to its remarkable thermal stability and optoelectronic properties. However, realizing the CsPbI3 perovskite with high black‐phase stability and optoelectronic properties remains a significant challenge, which largely affects the photovoltaic performance of perovskite solar cells (PSCs). Herein, aromatic ammonium agents are used to modulate the crystallization of the CsPbI3 perovskite to improve its black‐phase stability and optoelectronic properties for efficient PSCs. Systemically experimental studies and comprehensively theoretical calculations are performed, which reveal that histammonium dihydrochloride (HACl2) could strongly couple with the perovskite during its crystallization, leading to faster nucleation and slower perovskite growth, and thus modulating the crystallization dynamics of the perovskites. Moreover, the residual diammonium cations (HA2+) distributed at the grain boundaries and on the surface of the perovskites can effectively passivate defects through electrostatic interactions, substantially suppressing trap‐assisted nonradiative recombination, and prompting more matched perovskite surface energetics. Consequently, the photovoltaic performance of CsPbI3 PSCs is largely improved because of a combination of enhanced crystallinity and optoelectronic properties of the perovskites. This work offers a new avenue to prepare inorganic perovskites with high optoelectronic properties for photovoltaics. [ABSTRACT FROM AUTHOR]

Recently, distributed cooperative control has been popularly used in the secondary control of microgrids due to its reliability and flexibility. However, traditional distributed control schemes based on fixed‐cycle communication usually result in a waste of communication resources. Thus, this paper proposes an event‐triggered distributed control strategy that can significantly reduce the requirements of communication. In addition, compared with existing schemes, the proposed algorithm can achieve the secondary control goal in a directed graph, which can be applied to more scenarios, especially for weaker communication conditions. The stability of the strategy is investigated with the Lyapunov method. The simulation results verify the validity and effectiveness of the proposed scheme. [ABSTRACT FROM AUTHOR]

Here, cutting properties and wear mechanism of the home‐made B4C‐TiB2‐SiC ceramic cutting tools in turning of AISI 4340 steel workpieces were studied through a combination of finite element simulation using Deform‐3D software and turning experiments. Simulation results show that cutting parameters have significant effects on the main cutting force and tool temperature of the B4C‐TiB2‐SiC cutting tool. The optimal cutting parameters for the ceramic cutting tool are cutting speed of 300 m/min, depth of cut of.3 mm, and feed rate of.1 mm/r. Experimental results show the cutting length of the B4C‐TiB2‐SiC cutting tool is about 101 m, which is 21.0% and 32.9% larger than that of the home‐made B4C‐TiB2 ceramic cutting tool and commercially available tungsten carbide tool, indicating that the B4C‐TiB2‐SiC cutting tool has a desired service life. The surface roughness of the workpieces processed by the B4C‐TiB2‐SiC cutting tool is 2.43 µm, which is 29.4% lower than that of the workpieces processed by the B4C‐TiB2 cutting tool, indicating that the B4C‐TiB2‐SiC cutting tool has a satisfying machining accuracy. Wear forms of the B4C‐TiB2‐SiC ceramic cutting tool involve craters, chipping, and flank wear, and the main wear mechanisms are abrasive, adhesive, oxidative, and diffusion wear. [ABSTRACT FROM AUTHOR]

Proton exchange membrane (PEM) plays a relatively significant part in PEM fuel cells (PEMFCs). In this study, ionic liquid were grafted onto boron nitride (ILs@BN) were prepared by wet ball milling, and the polyimide (PI) composite films with different contents (1, 2, 3, 4, and 5 wt%) of ILs@BN were fabricated by solution‐casting method. Results showed that compared with the original polyimide films, the performance of the obtained composite films has been significantly improved. Tensile strength of film containing 4 wt% ILs@BN was enormously enhanced by 93.62% (from 47 to 91.8 MPa), respectively, in contrast to pure PI film. Compared with pure PI film, film containing with 4 wt% ILs@BN was reduced from 71.2° to 63.2°, which indicated the better hydrophilicity of the film and potential proton transport channels. The composite film exhibited excellent proton conductivity, which was tremendously elevated by 58.35% (from 0.1215 S cm−1 for pure PI to 0.1924 S cm−1 for film containing with 4 wt% ILs@BN). Comprehensively, the film containing with 4 wt% ILs@BN presenting excellent mechanical properties (91.8 MPa), contact angle (63.2°) and proton conductivity (0.1924 S cm−1) demonstrating strong potential applications in fuel cells. [ABSTRACT FROM AUTHOR]

Purposely changing the rate‐determining step (RDS) of oxygen evolution reaction (OER) remains a major challenge for enhancing the energy efficiency of electrochemical splitting of water. Here we show that the OER RDS can be regulated by simply varying the cation and anion complexity in a family of the metal phosphorous trichalcogenide electrocatalysts (MPT3, where M=Fe, Ni; T=S, Se), achieving an exceptionally high OER activity in (Ni,Fe)P(S,Se)3, as demonstrated by its ultra‐low Tafel slope (34 mV dec−1) and a very low overpotential compared to many relevant OER catalysts. This is strongly supported by density functional theory calculations, which showed that this catalyst has a nearly optimal OER activity descriptor value of ΔG(O*)−ΔG(OH*)=1.5 eV. We also found that the activity descriptor is proportional to a newly proposed cation/anion complexity index that consists of pairwise contributions from cation‐anion bonds in a catalyst compound, revealing the pivotal role of the cation‐anion interactions in determining the catalyst performance and providing a simple way for predicting catalytic activities. [ABSTRACT FROM AUTHOR]

Purpose: We aimed to improve B0 magnetic field homogeneity and minimize the interference between RF coils and local B0 shimming coils with few channel numbers. Methods: To design and construct the prototype for B0 shimming of the rat brain, we first evaluated the interferences of single shimming loops on RF receiver loops. Then, B0 shimming of the whole rat brain was implemented using an optimization procedure. The positions and currents of the local shimming coils with channel numbers from 3 to 6 were optimized to improve shimming performance. Based on the simulation results, a 5‐channel local shimming coil, combined with a 3‐channel RF receiver coil, was constructed and evaluated by animal experiments. Results: There was marginal SNR loss within 5% after integrating the local shimming coil into the RF receiver coil. With respect to the Siemens standard shims up to second order, the B0 inhomogeneity in one whole rat brain was reduced from 39.6 Hz to 24.7 Hz by using the local shimming coil. A large portion of the EPI distortions was recovered after using the 5‐channel local shimming coil. The temporal SNR using the local shimming coil was higher than that using the Siemens standard shims up to second order, with an improvement of more than 24%. Conclusions: The local shimming coil can improve B0 magnetic field homogeneity despite minor effects on the RF coil and can benefit a variety of applications that are sensitive to B0 inhomogeneity. Nevertheless, EPI for rat brain is still very challenging. [ABSTRACT FROM AUTHOR]

Purpose: To develop an ultrafast and robust MR parameter mapping network using deep learning. Theory and Methods: We design a deep learning framework called SuperMAP that directly converts a series of undersampled (both in k‐space and parameter‐space) parameter‐weighted images into several quantitative maps, bypassing the conventional exponential fitting procedure. We also present a novel technique to simultaneously reconstruct T1rho and T2 relaxation maps within a single scan. Full data were acquired and retrospectively undersampled for training and testing using traditional and state‐of‐the‐art techniques for comparison. Prospective data were also collected to evaluate the trained network. The performance of all methods is evaluated using the parameter qualification errors and other metrics in the segmented regions of interest. Results: SuperMAP achieved accurate T1rho and T2 mapping with high acceleration factors (R = 24 and R = 32). It exploited both spatial and temporal information and yielded low error (normalized mean square error of 2.7% at R = 24 and 2.8% at R = 32) and high resemblance (structural similarity of 97% at R = 24 and 96% at R = 32) to the gold standard. The network trained with retrospectively undersampled data also works well for the prospective data (with a slightly lower acceleration factor). SuperMAP is also superior to conventional methods. Conclusion: Our results demonstrate the feasibility of generating superfast MR parameter maps through very few undersampled parameter‐weighted images. SuperMAP can simultaneously generate T1rho and T2 relaxation maps in a short scan time. [ABSTRACT FROM AUTHOR]

The inorganic hole transport layer of nickel oxide (NiOx) has shown highly efficient, low‐cost, and scalable in perovskite photovoltaics. However, redox reactions at the interface between NiOx and perovskites limit their commercialization. In this study, ABABr (4‐(2‐Aminoethyl) benzoic acid bromide) between the NiOx and different perovskite layers to address the issues has been introduced. How the ABABr interacts with NiOx and perovskites is experimentally and theoretically investigated. These results show that the ABABr molecule chemically reacts with the NiOx via electrostatic attraction on one side, whereas on the other side, it forms a strong hydrogen bond via the NH3+ group with perovskites layers, thus directly diminishing the redox reaction between the NiOx and perovskites layers and passivating the layer surfaces. Additionally, the ABABr interface modification leads to significant improvements in perovskite film morphology, crystallization, and band alignment. The perovskites solar cells (PSCs) based on an ABABr interface modification show power conversion efficiency (PCE) improvement by over 13% and maintain over 90% of its PCE after continuous operation at maximum power point for over 500 h. The work not only contributes to the development of novel interlayers for stable PSCs but also to the understanding of how to prevent interface redox reactions. [ABSTRACT FROM AUTHOR]

Surface passivation engineering of perovskite films via organic functional small molecules has emerged as an effective strategy for improving the efficiency and stability of perovskite solar cells (PSCs). However, a systematic understanding of underlying mechanisms behind these improvements is still missing. In this work, two new naphthalimide‐based organic small molecules (PX, X = F, I) are designed and employed to efficiently passivate the surface defects of perovskite films in PSCs. Consequently, superior photovoltaic properties for PI‐treated PSCs are achieved with a power conversion efficiency of 23.06%, which is significantly higher than that of the reference device without passivators (20.45%). Theoretical calculations reveal that PX can give rise to interfacial electrical dipole. It is found that incorporating a dipole interlayer between perovskite layer and hole transport layer can enhance ultrafast charge‐carrier injection and suppress the charge‐carrier recombination in device, which is illustrated by transient absorption spectroscopy. These present results can provide valuable information on the understanding interfacial charge‐carrier dynamics in PSCs to further improve the device performance. [ABSTRACT FROM AUTHOR]

Ubiquitous surface wrinkling has been well‐studied theoretically and experimentally. How to modulate the stress state of a liquid‐supported system for the unexploited wrinkling capabilities remains a challenge. Here we report a simple linearly‐polarized‐light illumination to spatiotemporally trigger ultrasensitive in situ dynamic wrinkling on a floating azo‐film. The smart combination of the liquid substrate with photoresponsive azo‐moieties leads to the light‐induced ultrafast wrinkling evolution, accompanied by unprecedented sequential wrinkling orientation conversion (from polarization‐parallel to polarization‐perpendicular). The involved different polarization‐dependent sequential photo‐orientation for azo side chains and azo‐grafted main chains of azopolymers is disclosed experimentally for the first time. Meanwhile, programmable dynamic wrinkling with all‐optical switchable surface topographies is available, which has wide application potentials in photoresponsive soft photonics. [ABSTRACT FROM AUTHOR]

Glioblastoma (GBM) is the most common primary malignant brain tumor in adults. Temozolomide (TMZ) is used as the standard chemotherapeutic agent for GBM but with limited success, and treatment failure is mainly due to tumor resistance. One of the leading causes of TMZ resistance is the upregulation of the DNA repair mechanism. Therefore, targeting the DNA damage response (DDR) is proposed to be an effective strategy to sensitize tumor cells to TMZ. In the present study, we demonstrated that the combined use of the PI3K inhibitor ZSTK474 and TMZ showed synergetic anticancer effects on human GBM cells in vitro and in vivo. The combination treatment led to significantly increased cell apoptosis and DNA double strand breaks (DSBs). In addition, a mechanistic study indicated that TMZ enhanced the homologous recombination (HR) repair efficiency in GBM cells, while ZSTK474 impaired HR repair by blocking the phosphorylation of ATM and the expression of BRCA1/2 and Rad51, thereby sensitizing GBM cells to TMZ. Moreover, TMZ activated the PI3K signaling pathway through upregulation of the PI3K catalytic subunits p110α and p110β and the phosphorylation of Akt. Meanwhile, ZSTK474 blocked the activity of the PI3K/Akt pathway. Taken together, our findings suggested that the combination of ZSTK474 and TMZ might be a potential therapeutic option for GBM. [ABSTRACT FROM AUTHOR]

Cs2AgBiBr6, has recently gained wide attention as a possible alternative to lead‐halide perovskites, considering the nontoxicity and improved stability. However, this double perovskite suffers from defects, especially deep electron traps, severely hampering the photovoltaic performance. This work reports a simple method to control the double perovskite crystallization by adding volatile salts into the precursor solution. X‐ray diffraction patterns reveal that the organic cation with suitable radius (such as methylammonium, MA+) is introduced into the perovskite lattice, forming an organic/inorganic mixed double perovskite intermediate phase. The organic salt is thereafter fully evaporated during high temperature annealing, and the all‐inorganic double perovskite is obtained with dense surface and less pin‐holes. From optical and electrical characterization, it is concluded that the Cs2AgBiBr6 film exhibits high quality, with higher light absorptance and emission. Reduced trap density and longer carrier lifetime are also observed. The improved Cs2AgBiBr6 film is beneficial for efficient carrier collection with suppressed defect‐assisted recombination. With this strategy, a power conversion efficiency (PCE) of 2.53% is achieved for the champion Cs2AgBiBr6‐based solar cell device, which is significantly higher compared to the control device with 1.43% PCE. This work is therefore helpful for further improvement of inorganic lead‐free perovskite materials for optoelectronic applications. [ABSTRACT FROM AUTHOR]

Calciphylaxis, also known as calcific uremic arteriolopathy (CUA), is typically characterized by subcutaneous tissue calcification and excruciatingly painful cutaneous lesions with high mortality. It is critical for dermatologists to make early diagnosis and appropriate management, yet currently only 56% of calciphylaxis cases are correctly diagnosed by conventional histological stain1. Specially, the identification of subtle calcium deposits of subcutaneous can be challenging but is believed crucial for early diagnosis of calciphylaxis2. More sensitive calcification staining is in high demand. In this study, Fluo‐3 AM was found to be a rapid, sensitive and reliable fluorescent probe for the detection of calcium deposits and could be a promising diagnostic tool for calciphylaxis. [ABSTRACT FROM AUTHOR]

Aim: An increasing number of exotic plants and their biological control agents are being introduced into new regions. Therefore, it is necessary to study their interactions and to manage the future directions of plant invasions under different scenarios of temperature rise. Location: China. Method: We investigated the distribution patterns of the two most prevalent invasive aquatic plants in the world, Alternanthera philoxeroides and Eichhornia crassipes, at a large scale and studied the interactions of both invasive plants with their respective biological control agents, Agasicles hygrophila and Neochetina eichhorniae, in response to different scenarios of temperature rise. Results: Both plants performed better in warmer climates in common garden experiments. However, large populations of A. philoxeroides occurred only in the temperate zone because this species experienced competitive exclusion from E. crassipes and suppression due to A. hygrophila herbivory in tropical and subtropical areas. Moreover, in both subtropical zones, where the two plants and A. hygrophila co‐occur, and the temperate zone, where only A. philoxeroides occurs at present, A. hygrophila herbivory and the competition from E. crassipes hindered the performance of A. philoxeroides. Moreover, in the extreme high‐temperature environment, A. philoxeroides performance improved, while E. crassipes performance worsened. In addition, the combination of N. eichhorniae herbivory and competition from A. philoxeroides also reduced the performance of E. crassipes, but E. crassipes still dominated when in competition with A. philoxeroides. Main conclusions: Our results indicate that climate warming and the introduction of herbivores do not alter the interspecific relationship between E. crassipes and A. philoxeroides. Moreover, our study suggests that under climate warming, E. crassipes will replace A. philoxeroides as the dominant species in some communities in warm temperate zones, though extremely high‐temperature events will slow this replacement process. [ABSTRACT FROM AUTHOR]

Purpose: To develop a deep learning–based reconstruction framework for ultrafast and robust diffusion tensor imaging and fiber tractography. Methods: SuperDTI was developed to learn the nonlinear relationship between DWIs and the corresponding diffusion tensor parameter maps. It bypasses the tensor fitting procedure, which is highly susceptible to noises and motions in DWIs. The network was trained and tested using data sets from the Human Connectome Project and patients with ischemic stroke. Results from SuperDTI were compared against widely used methods for tensor parameter estimation and fiber tracking. Results: Using training and testing data acquired using the same protocol and scanner, SuperDTI was shown to generate fractional anisotropy and mean diffusivity maps, as well as fiber tractography, from as few as six raw DWIs, with a quantification error of less than 5% in all white‐matter and gray‐matter regions of interest. It was robust to noises and motions in the testing data. Furthermore, the network trained using healthy volunteer data showed no apparent reduction in lesion detectability when directly applied to stroke patient data. Conclusions: Our results demonstrate the feasibility of superfast DTI and fiber tractography using deep learning with as few as six DWIs directly, bypassing tensor fitting. Such a significant reduction in scan time may allow the inclusion of DTI into the clinical routine for many potential applications. [ABSTRACT FROM AUTHOR]

The surface passivation of colloidal quantum dots (CQD) is critical for the electronic coupling of CQDs, which significantly affects the photovoltaic performance of CQD solar cells (CQDSCs). Herein, a self‐assemble passivation (SAP) strategy of CQDs is introduced to improve CQD coupling. The PbI2 passivation layer prepared using the SAP method can largely improve surface defect passivation of CQDs, diminishing charge recombination induced by the sub‐bandgap traps. Meanwhile, extensive theoretical simulations reveal that the self‐assembled PbI2 passivation layer works as a "charger bridge" for charge transport between the adjacent CQDs, avoiding CQD fusion. The infrared CQDSCs are fabricated and the SAP‐based CQDSC yields an efficiency of up to 12.3%, which is significantly improved compared with that of the conventional CQDSCs with iodide passivating CQD surface. The improved photovoltaic performance in the SAP‐based CQDSCs is attributed to increased charge extraction, resulting from strong CQD coupling within the CQD solid films. This work provides a simple and facile way to improve the electronic coupling of CQDs for high‐performance infrared CQDSCs. [ABSTRACT FROM AUTHOR]

Background: Endothelial‐to‐mesenchymal transition (EndMT) is a common pathophysiology in valvular calcification (VC) among non‐chronic kidney disease (CKD) patients. However, few studies were investigated in CKD‐induced VC. Parathyroid hormone (PTH) was considered to be an important component of EndMT in CKD‐induced cardiovascular diseases. Therefore, determining whether PTH could induce valvular EndMT and elucidating corresponding mechanism involved further study. Methods: Performing a 5/6 nephrectomy with a high phosphorus diet was done to construct VC models in rats with CKD. miRNA sequencing was used to ascertain changes in microRNA in human umbilical vein endothelial cells (HUVECs) intervened by PTH. VC was observed by Von Kossa staining and scanning electron microscope. Results: PTH induced valvular EndMT in VC. Global microRNA expression profiling of HUVECs was examined in PTH versus the control in vitro, in which miR‐29a‐5p was most notably decreased and was resumed by PTHrP(7‐34) (PTH‐receptor1 inhibitor). Overexpression of miR‐29a‐5p could inhibit PTH‐induced EndMT in vitro and valvular EndMT in vivo. The dual‐luciferase assay verified that γ‐secretase‐activating protein (GASP) served as the target of miR‐29a‐5p. miR‐29a‐5p‐mimics, si‐GSAP and DAPT (γ‐secretase inhibitor) inhibited PTH‐induced γ‐secretase activation, thus blocking Notch1 pathway activation to inhibit EndMT in vitro. Moreover, Notch1 pathway activation was observed in VC. Blocking Notch1 pathway activation via AAV‐miR‐29a and DAPT inhibited valvular EndMT. In addition, blocking Notch1 pathway activation was also shown to alleviate VC. Conclusion: PTH activates valvular EndMT via miR‐29a‐5p/GSAP/Notch1 pathway, which can contribute to VC in CKD rats. [ABSTRACT FROM AUTHOR]

Large‐scale synthesis of micromotors powered by visible light and pure water is challenging, yet crucial for practical applications. Herein, a new method for large‐scale synthesis of uniform Janus ZnO micromotors is reported, by partially encapsulating a ZnO microsphere within a polysiloxane microsphere. The resulting micromotors autonomously move under visible light and in pure water at speeds up to 15 μm/s. The shapes of these micromotors are readily tuned by adjusting the chemicals used in the synthesis, and the influence of the shapes on the speeds of the micromotors is quantified. Moreover, interesting collective behaviors, such as the formation of dynamic clusters, emerge from a dense population of these micromotors. This study therefore represents a substantial step forward in building an excellent model system of good quantity, uniformity and tunability for the study of active matter as well as in a variety of practical applications. [ABSTRACT FROM AUTHOR]

When performing a search and rescue mission, unmanned aerial vehicles (UAVs) should continuously search targets above the mission area. In order to transfer the search and rescue information quickly and efficiently, two types of UAVs, the ferrying UAVs and the searching UAVs, are used to complete the mission. Obviously, this application scenario requires an efficient path planning method for ferrying UAVs. The existing path planning methods for ferrying UAVs usually focus on shortening the path length and ignore the different initial energy of ferrying UAVs. However, the following problem does exist: if the ferrying UAV with less initial energy is assigned a longer path, meaning that the ferrying UAV with less initial energy will ferry messages for more searching UAVs. When the lower-initial-energy ferrying UAV is running out of energy, more searching UAVs will no longer deliver messages successfully. Therefore, the mismatch between the planned path length and the initial energy will eventually result in a lower global message delivery ratio. To solve this problem, we propose a new concept energy-factor for a ferrying UAV and use the variance of all ferrying UAVs' energy-factor to measure the balance between the planned path length and the initial energy. Further, we model the energy-balanced path-planning problem for multiple ferrying UAVs, which actually is a multiobject optimization problem of minimizing the planned path length and minimizing the variance of all ferrying UAVs' energy-factor. Based on the genetic algorithm, we design and implement an energy-balanced path planning algorithm (EMTSPA) for multiple ferrying UAVs to solve this multiobject optimization problem. Experimental results show that EMTSPA effectively increases the global message delivery ratio and decreases the global message delay. [ABSTRACT FROM AUTHOR]

The k-means algorithm is sensitive to the outliers. In this paper, we propose a robust two-stage k-means clustering algorithm based on the observation point mechanism, which can accurately discover the cluster centers without the disturbance of outliers. In the first stage, a small subset of the original data set is selected based on a set of nondegenerate observation points. The subset is a good representation of the original data set because it only contains all those points that have a higher density of the original data set and does not include the outliers. In the second stage, we use the k-means clustering algorithm to cluster the selected subset and find the proper cluster centers as the true cluster centers of the original data set. Based on these cluster centers, the rest data points of the original data set are assigned to the clusters whose centers are the closest to the data points. The theoretical analysis and experimental results show that the proposed clustering algorithm has the lower computational complexity and better robustness in comparison with k-means clustering algorithm, thus demonstrating the feasibility and effectiveness of our proposed clustering algorithm. [ABSTRACT FROM AUTHOR]

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Aim: Imbalance of M1/M2 macrophages phenotype activation is a key point in diabetic nephropathy (DN). This study aimed to investigate whether active vitamin D (VD) suppresses macrophage transition to the M1 phenotype via inhibiting the high glucose‐induced STAT‐1 phosphorylation to reduce TREM‐1 expression. Methods: In vivo, pathological changes in kidney tissue were detected and the expression of CD68 TREM‐1, STAT‐1, M1 makers, and M2 makers were acquired in renal tissue of patients with DN and 18w DN rats. In vitro, RAW 264.7 cells were incubated in the presence of high glucose with or without VD. Silencing and overexpression of TREM‐1 and silencing and activate of STAT‐1 were explored to elucidate the underlying mechanism. The expression of TREM‐1 and STAT‐1 and the changes of macrophage phenotype were examined separately by western blot and immunofluorescence staining. Results: (a) Expression of TREM‐1, p‐STAT‐1, and M1 markers (iNOS and TNF‐α) were increased and positively correlated in kidneys from patients with DN. (b) In DN rats, the enlargement of glomerular surface area, expansion of glomerular mesangial matrix, the expression of CD68, TREM‐1, p‐STAT‐1, and M1 marker (iNOS) were significantly increased in comparison with the normal control group, whereas above changes were markedly decreased in the diabetic group treated with the VD group. (c) In vitro, VD significantly decreased high glucose‐induced CD68, TREM‐1, p‐STAT‐1, and M1 marker (iNOS) expression. However, above‐mentioned effects of VD are abolished when TREM‐1 is overexpressed or STAT‐1 is activated. Reductions in STAT‐1 expression decreased the TREM‐1 expression. Conclusion: VD can inhibit macrophage transition to the M1 phenotype through the STAT‐1/TREM‐1 pathway. Vitamin D can inhibit macrophage transition to the M1 phenotype through the STAT‐1/TREM‐1 pathway. [ABSTRACT FROM AUTHOR]

Facing serious environment problem and unbalanced distribution of energy resources, power grid interconnection is thought to be a significant way to the effective utilisation of renewable energy. High penetration of renewable energy brings a lot of problems to the planning and operation of power system. Considering seasonal and diurnal scales, wind and solar energy are complementary. In this study, a power gird interconnection model using linear programming techniques to minimise overall system costs was proposed, using high-voltage direct current (HVDC) to link the power systems in Northeast Asia in view of the difference in the countries' power system. The model not only considers generation and transmission extensions, but also sets the cross border power flows. To carbon emission reduction and fuel cost saving, four power grid interconnection programmes in Northeast Asia have been setup. The results show that power grid interconnection can bring environment and economic benefits. [ABSTRACT FROM AUTHOR]

Offshore wind power resource, which is relatively stable, abundant, and with modest impact on the environment, is a kind of clean and renewable energy suitable for large-scale development. Offshore wind farms have different topological structures of the collection system, such as AC parallel type, DC parallel type, DC series type, single-ring type, and double-ring type. The purpose of this paper is to analyse reliability and economy for various topologies and provide an insight into wind farm construction. In this study, the topology structure of various offshore wind farms is introduced firstly. Then, the reliability assessment methods are proposed. The reliability of the chain wind farm is analysed with the reliability block diagrams, while the reliability of the ring wind farm is analysed by using the classification method. In addition, the economy is evaluated considering investment costs. The investment cost for each type of component is calculated separately, which contributes to assessing the investment cost of the whole offshore wind farm. Detailed results from a case study, which includes 96 wind turbines, demonstrate that the DC series–parallel wind farm has superiority in reliability and economy, as well as in terms of its potential applications. [ABSTRACT FROM AUTHOR]

The fractional frequency transmission system (FFTS) can multiply increase transmission capacity by using a lower frequency to reduce the reactance of the AC transmission system. The modular multi-level matric converter (M3C) as the new generation of the AC/AC converter is the critical equipment of FFTS. The self-start control strategy for M3C-based FFTS is proposed and the whole start-up procedure is divided into the uncontrollable stage and controllable stage. The model of the equivalent circuit in an uncontrollable stage is built and the mathematical relation between the maximum charging current and the current-limit resistor is obtained. Finally, a digital simulation system of M3C-based FFTS is established, and the effectiveness of the proposed control strategies is verified by simulation results. [ABSTRACT FROM AUTHOR]

Herein, we report on layer‐by‐layer MnCo2O4/NiMn double hydroxide (LDH) nanosheet arrays (NAs) that are designed and synthesized by in‐situ growing the NiMn LDH NAs onto the surface of the MnCo2O4 NAs. The layer‐by‐layer architecture together with the synergistic effects between the NiMn LDH and MnCo2O4 components, substantially improves the energy storage performance of the composite NAs electrodes. The optimized composite NAs electrode exhibits a high specific capacitance of 3063 F g−1 at 3 A g−1 (four times with respect to the individual MnCo2O4 electrode), a capacitance retention of 2315 F g−1 at 30 A g−1, and a cycle stability with 94.7 % capacitance retention at 20 A g−1 over 5000 cycles. Moreover, an assembled MnCo2O4/NiMn LDH//active carbon (AC) asymmetric solid‐state supercapacitor (ASSC) is found to achieve a high energy density of 51.9 W h kg−1 at 806 W kg−1. These findings might offer a feasible strategy to synthesize the high‐performance MnCo2O4‐based composite electrodes for supercapacitors (SCs). Layer‐by‐layer: hierarchical MnCo2O4/NiMn layered double hydroxide nanosheet arrays are designed and synthesized as supercapacitor electrode with significantly enhanced electrochemical performance. A solid‐state asymmetric supercapacitor is assembled, using activated carbon as counter electrode. The device exhibits a high energy density, showing the promising potential of the presented strategy for the synthesis of high‐performance materials. [ABSTRACT FROM AUTHOR]

A hot‐injection synthesis method was used to synthesize low‐toxicity Ag2S colloidal quantum dots (CQDs) with strong and broad light absorption as an ultra‐thin photo‐absorber in CQD heterojunction solar cells. By using iodide and sulfur linkers it was possible to accomplish efficient charge carrier extraction, resulting in a high photocurrent due to the broad absorption spectrum. Transient photovoltage decay measurements were used to obtain information about trap states in the CQDs and the effect on the lifetime of the photoinduced carriers. The devices show very promising stability under constant long‐term illumination and they are stable under ambient storage conditions with low losses to the performance over a period of over two months. These results show that Ag2S CQDs have high potential within solar cell applications, and point the direction for further improvements. Shine on: Low‐toxicity silver‐sulfide colloidal quantum dots synthesized with hot‐injection are utilized as the photoactive layer in a solar cell with promising photocurrent and long‐term stability. [ABSTRACT FROM AUTHOR]

Abstract: Solution‐processed colloidal quantum dot (CQD) solar cells harvesting the infrared part of the solar spectrum are especially interesting for future use in semitransparent windows or multilayer solar cells. To improve the device power conversion efficiency (PCE) and stability of the solar cells, surface passivation of the quantum dots is vital in the research of CQD solar cells. Herein, inorganic CsPbI3 perovskite (CsPbI3‐P) coating on PbS CQDs with a low‐temperature, solution‐processed approach is reported. The PbS CQD solar cell with CsPbI3‐P coating gives a high PCE of 10.5% and exhibits remarkable stability both under long‐term constant illumination and storage under ambient conditions. Detailed characterization and analysis reveal improved passivation of the PbS CQDs with the CsPbI3‐P coating, and the results suggest that the lattice coherence between CsPbI3‐P and PbS results in epitaxial induced growth of the CsPbI3‐P coating. The improved passivation significantly diminishes the sub‐bandgap trap‐state assisted recombination, leading to improved charge collection and therefore higher photovoltaic performance. This work therefore provides important insight to improve the CQD passivation by coating with an inorganic perovskite ligand for photovoltaics or other optoelectronic applications. [ABSTRACT FROM AUTHOR]

Under the complex oceanic environment, robust and effective feature extraction is the key issue of ship radiated noise recognition. Since traditional feature extraction methods are susceptible to the inevitable environmental noise, the type of vessels, and the speed of ships, the recognition accuracy will degrade significantly. Hence, we propose a robust time-frequency analysis method which combines resonance-based sparse signal decomposition (RSSD) and Hilbert marginal spectrum (HMS) analysis. First, the observed signals are decomposed into high resonance component, low resonance component, and residual component by RSSD, which is a nonlinear signal analysis method based not on frequency or scale but on resonance. High resonance component is multiple simultaneous sustained oscillations, low resonance component is nonoscillatory transients, and residual component is white Gaussian noises. According to the low-frequency periodic oscillatory characteristic of ship radiated noise, high resonance component is the purified ship radiated noise. RSSD is suited to noise suppression for low-frequency oscillation signals. Second, HMS of high resonance component is extracted by Hilbert-Huang transform (HHT) as the feature vector. Finally, support vector machine (SVM) is adopted as a classifier. Real audio recordings are employed in the experiments under different signal-to-noise ratios (SNRs). The experimental results indicate that the proposed method has a better recognition performance than the traditional method under different SNRs. [ABSTRACT FROM AUTHOR]

Single-walled carbon nanotubes (SWCNTs) show great potential as an alternative material for front electrodes in photovoltaic applications, especially for flexible devices. In this work, a press-transferred transparent SWCNT film was utilized as front electrode for colloidal quantum dot solar cells (CQDSCs). The solar cells were fabricated on both glass and flexible substrates, and maximum power conversion efficiencies of 5.5 and 5.6 %, respectively, were achieved, which corresponds to 90 and 92 % of an indium-doped tin oxide (ITO)-based device (6.1 %). The SWCNTs are therefore a very good alternative to the ITO-based electrodes especially for flexible solar cells. The optical electric field distribution and optical losses within the devices were simulated theoretically and the results agree with the experimental results. With the optical simulations that were performed it may also be possible to enhance the photovoltaic performance of SWCNT-based solar cells even further by optimizing the device configuration or by using additional optical active layers, thus reducing light reflection of the device and increasing light absorption in the quantum dot layer. [ABSTRACT FROM AUTHOR]

Highly dispersed Pt-CeO2 hybrids arched on reduced graphene oxide (Pt-CeO2/rGO) were facilely synthesized by a combination of the reverse micelle technique and a redox reaction without any additional reductant or surfactant. Under a N2 atmosphere, the redox reaction between Ce3+ and Pt2+ occurs automatically in alkaline solution, which results in the formation of Pt-CeO2/rGO nanocomposites (NCs). The as-synthesized Pt-CeO2/rGO NCs exhibit superior catalytic performance relative to that shown by the free Pt nanoparticles, Pt/rGO, Pt-CeO2 hybrid, and the physical mixture of Pt-CeO2 and rGO; furthermore, the nanocomposites show significantly better activity than the commercial Pt/C catalyst toward the hydrolysis of ammonia borane (NH3BH3) at room temperature. Moreover, the Pt-CeO2/rGO NCs have remarkable stability, and 92 % of their initial catalytic activity is preserved even after 10 runs. The excellent activity of the Pt-CeO2/rGO NCs can be attributed not only to the synergistic structure but also to the electronic effects of the Pt-CeO2/rGO NCs among Pt, CeO2, and rGO. [ABSTRACT FROM AUTHOR]

Purpose To develop a lump-element double-tuned common-mode-differential-mode (CMDM) radiofrequency (RF) surface coil with independent frequency tuning capacity for MRS and MRI applications. Methods The presented design has two modes that can operate with different current paths, allowing independent frequency adjustment. The coil prototype was tested on the bench and then examined in phantom and in vivo experiments. Results Standard deviations of frequency and impedance fluctuations measured in one resonator, while changing the tuning capacitor of another resonator, were less than 13 kHz and 0.55 Ω. The unloaded S21 was −36 dB and −41 dB, while the unloaded Q factor was 260 and 287, for 13C and 1H, respectively. In vivo hyperpolarized 13C MR spectroscopy data demonstrated the feasibility of using the CMDM coil to measure the dynamics of lactate, alanine, pyruvate and bicarbonate signal in a normal rat head along with acquiring 1H anatomical reference images. Conclusion Independent frequency tuning capacity was demonstrated in the presented lump-element double-tuned CMDM coil. This CMDM coil maintained intrinsically decoupled magnetic fields, which provided sufficient isolation between the two resonators. The results from in vivo experiments demonstrated high sensitivity of both the 1H and 13C resonators. Magn Reson Med 76:1612-1620, 2016. © 2015 International Society for Magnetic Resonance in Medicine [ABSTRACT FROM AUTHOR]

Nanodot-textured surface, nanorod-textured surface and nanocomposite-textured surface were prepared by the hydrothermal technique and successive ion layer absorption and reaction technique. The adhesion and friction properties of the three kinds of nanotextured surfaces were investigated using an atomic force microscope colloidal probe. Experimental results revealed that the nanorod-textured surface and nanocomposite-textured surface can significantly reduce adhesive and friction forces compared with a nanodot-textured surface. The main reason for this phenomenon was that the nanorod and nanocomposite textures can reduce contact area between the sample surface and the colloidal probe. The effects of surface root mean square roughness, applied load and sliding velocity on the adhesion and friction behaviors of the nanotextured surfaces were investigated. The adhesive and friction forces of the nanotextured surfaces decreased with the increasing surface root mean square roughness. Compared with the nanocomposite-textured surface, the nanorod-textured surface has better adhesion and frictional performance. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

An ideal inerter has been applied to various vibration engineering fields because of its superior vibration isolation performance. This paper proposes a new type of fluid inerter and analyzes the nonlinearities including friction and nonlinear damping force caused by the viscosity of fluid. The nonlinear model of fluid inerter is demonstrated by the experiments analysis. Furthermore, the full-car dynamic model involving the nonlinear fluid inerter is established. It has been detected that the performance of the vehicle suspension may be influenced by the nonlinearities of inerter. So, parameters of the suspension system including the spring stiffness and the damping coefficient are optimized by means of QGA (quantum genetic algorithm), which combines the genetic algorithm and quantum computing. Results indicate that, compared with the original nonlinear suspension system, the RMS (root-mean-square) of vertical body acceleration of optimized suspension has decreased by 9.0%, the RMS of pitch angular acceleration has decreased by 19.9%, and the RMS of roll angular acceleration has decreased by 9.6%. [ABSTRACT FROM AUTHOR]

Purpose: Carotid artery diseases due to plaque buildup at the carotid bifurcation are a leading cause of stroke. Accurate plaque quantification and characterization of plaque composition and morphology by magnetic resonance imaging(MRI) is essential to identifying high-risk patients. Difficulties in detecting plaque, which is physically small, and the unique physiological structure of the carotid artery make use of a radio frequency (RF) coil array with high resolution, large longitudinal coverage, and deep penetration ideal for clinical examinations. The goal of this project was to design and fabricate a sensitive RF coil array with sufficient imaging coverage and signal-to-noise ratio(SNR) for carotid arteryimaging at 3 T. Methods: Based on clinical requirements and the anatomical structure of the human carotid artery, an 8-channel carotid coil array was designed and fabricated for 3 T MRI of the carotid artery in humans. The performance of the proposed 8-channel carotid coil array was validated through bench tests and MR imaging experiments on a 3 T whole body MRI scanner. Its performance was also compared experimentally to the performance of a commercial 4-channel phased array carotid coil designed by Machnet BV (Machnet BV coil, Roden, Netherlands). Results: The 8-channel carotid coil array performed significantly better in imaging the carotid artery than the commercial 4-channel Machnet BV coil in terms of the SNR, coverage, and penetration depth. In parallel imaging, the proposed 8-channel carotid coil array demonstrated a much lower maximum value and average value of the geometry factor in the region of interest. Carotid arteryimages acquired in vivo using the proposed 8-channel carotid arterycoil and the commercial 4-channel Machnet BV coil were also compared, demonstrating the former's potential for clinical diagnosis. Conclusions: Based on the analyses of phantom and in vivoimaging studies, the proposed 8-channel carotid coil array has the potential for use in clinical diagnosis, performing better in terms of SNR,imaging coverage, and penetration depth than the commercial 4-channel carotid arterycoil array at 3 T. In future studies, the proposed 8-channel carotid coil array can also serve as an important part of a large-scale multichannel coil array for imaging the whole carotid artery system, including the extracranial and intracranial arteries. [ABSTRACT FROM AUTHOR]