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A novel concept to obtain the deep‐ultraviolet (DUV) nonlinear optical (NLO) materials is proposed based on the assembling of one‐dimensional (1D) polar motifs into quasi‐1D polymer patterns. Based on the first‐principles calculations, we have successfully discovered an excellent DUV NLO polymer, i.e. poly(difluorophosphazene), with the chemical formula of (PNF2)n. Calculations reveal that PNF2 has a larger band gap, a stronger second harmonic generation effect, a larger birefringence, and a shorter phase‐matching cutoff than KBe2BO3F2. These findings not only demonstrate that the PNF2 is the first reported DUV NLO polymer, but also could open a new direction to discover novel DUV NLO materials in polymer systems. [ABSTRACT FROM AUTHOR]

A novel concept to obtain the deep‐ultraviolet (DUV) nonlinear optical (NLO) materials is proposed based on the assembling of one‐dimensional (1D) polar motifs into quasi‐1D polymer patterns. Based on the first‐principles calculations, we have successfully discovered an excellent DUV NLO polymer, i.e. poly(difluorophosphazene), with the chemical formula of (PNF2)n. Calculations reveal that PNF2 has a larger band gap, a stronger second harmonic generation effect, a larger birefringence, and a shorter phase‐matching cutoff than KBe2BO3F2. These findings not only demonstrate that the PNF2 is the first reported DUV NLO polymer, but also could open a new direction to discover novel DUV NLO materials in polymer systems. [ABSTRACT FROM AUTHOR]

• Deep-UV nonlinear optical (NLO) crystals of NaBe 2 BO 3 F 2 were successfully grown. • Calculated refractive indices suggest NaBe 2 BO 3 F 2 is a viable deep-UV NLO crystal. • The structure-property relationships are compared across the entire KBBF family. The deep-ultraviolet (deep-UV) nonlinear optical (NLO) crystal NaBe 2 BO 3 F 2 (NBBF) is grown by the spontaneous nucleation method with the dimensions up to 20 × 20 × 1.5 mm3. The crystal structure was determined using single-crystal x-ray diffraction analysis and its space group was defined as C2 , which belongs to the biaxial class. The optical properties including the transmittance and the NLO coefficients were first determined. The band structure and density of states of NBBF were also calculated. Based on the calculated refractive indices, the Sellmeier equations were fitted to evaluate its ability for deep-UV laser generation. Our results suggest that NBBF is a viable deep-UV NLO crystal. [ABSTRACT FROM AUTHOR]

NASICON-structured Li1.5Al0.5Ge1.5(PO4)3 (LAGP) has been a promising solid-state glass-ceramic electrolyte for all-solid-state lithium ion batteries. However, the non-ideal ionic conductivity, non-uniformity of chemical composition, distortion and micro-cracks, etc., have limited its practical application. Considering these issues, in this work, we first of all introduce partial substitution of Al3+ by Ga3+. To avoid segregation of secondary phase, microwave sintering technology to prepare LAGP was used. With the help of microwave irradiation, sintering could be finished in just 30 min, and the size of crystals was homogeneous across the cross-section. No distortion and micro-cracks could be identified. Characterisations such as DTA, XRD, SEM and EIS were used to evaluate the material and electrochemical properties of the Li1.5Al0.5-xGaxGe1.5(PO4)3 (x = 0.1 ~ 0.5) samples. A high bulk conductivity of 6.67 × 10−4 S/cm at room temperature has been achieved when x = 0.1 and the activation energy was about 0.66 eV. [ABSTRACT FROM AUTHOR]

Abstract Ambient fine particulate matter (PM 2.5) has long been the primary air pollutant with alarming public health risk in China. PM 2.5 pollution control in China still mainly concerned concentration declining. The qualification and identification of PM 2.5 -attributable health loss is crucial for China's air quality improvement and pollution prevention. This study assessed the annual health loss and economic impact attributed to PM 2.5 exposure at a city level in China from 2015 to 2017. The health benefits from achieving specific PM 2.5 concentration control targets were estimated for 2020. The economic value of health loss in China was 3205.05, 3223.51, and 3344.80 billion Yuan in 2015, 2016, and 2017, representing 4.34%, 4.07%, and 3.85% of the gross domestic product of China. The health loss value in Beijing–Tianjin–Hebei (BTH) and surrounding areas and the Yangtze River Delta (YRD) urban agglomeration in 2017 was 731.93 and 520.27 billion Yuan, accounting for 21.88% and 15.56%, respectively, of the total economic value of all assessed cities. The economic value of health loss in provincial cities was high. From 2015 to 2017, high health loss in BTH and surrounding areas showed a diffusion trend toward cities in Henan, Shanxi, and Shaanxi Provinces. High health loss in the YRD urban agglomeration transferred to cities located in the middle and upper reaches of the Yangtze River. If PM 2.5 concentration control targets can be achieved by 2020, premature mortality attributed to PM 2.5 exposure will fall by 91,860 cases, representing 11.20% of which in 2017. This study, for the first time, highlighted the spatial distribution and temporal variation characteristics of health loss in Chinese cities based on ground-monitoring PM 2.5 concentration data and annual real-time population data. Distributional feature and time-trend analysis would provide a measurable assessment of health loss in Chinese cities to policymakers for effective allocating their efforts on air quality improvement. Graphical abstract Economic value of public health loss attributed to PM 2.5 exposure at the city level in 2017. Image 1 Highlights • We assessed the annual health loss and economic impact of PM 2.5 exposure in China. • We used PM 2.5 and population data (2015–2017) of prefecture-level cities or above. • Health loss declined from 0.91 (2015) to 0.82 (2017) million premature mortalities. • Annual economic value of health loss increased but declined as a percent of GDP. • Meeting updated PM 2.5 targets by 2020 could reduce mortality by 11% of 2017 levels. [ABSTRACT FROM AUTHOR]

Purpose: Tc-99m- and I-131-labeled arginine-arginine-leucine (RRL) peptides have shown the feasibility of tumor imaging in our previous studies. However, there have been no reports using RRL peptide for positron emission tomography (PET) imaging. In this study, RRL was radiolabeled with Ga-68 under optimized reaction conditions to develop a better specific and effective tumor imaging agent.Procedures: RRL was synthesized and conjugated to a bifunctional chelating agent (DOTA-NHS), then radiolabeled with Ga-68. Labeling yield was optimized by varying pH, temperature, and reaction time and the stability was evaluated in human fresh serum. Cellular uptakes of [68Ga]DOTA-RRL and FITC-conjugated RRL in HepG2 cells were evaluated using a gamma counter, confocal microscopy, and flow cytometry. PET images and biodistribution were performed in HepG2 tumor-bearing mice after injection of [68Ga]DOTA-RRL or [68Ga]GaCl3 at different time points. Further, blocking study was investigated using cold RRL.Results: The labeling yield of [68Ga]DOTA-RRL was 80.6 ± 3.9 % with a pH of 3.5-4.5 at 100 °C for 15 min. The cellular uptake of [68Ga]DOTA-RRL in HepG2 cells was significantly higher than that of [68Ga]GaCl3 (P < 0.05). Moreover, the high fluorescent affinity of FITC-conjugated RRL in HepG2 cells was shown using confocal microscopy and flow cytometry. After injection of [68Ga]DOTA-RRL in HepG2 tumor-bearing mice, tumor regions exhibited high radioactive accumulation over 120 min and the highest uptake at 30 min. After blocked with cold RRL, HepG2 tumors could not be visualized. [68Ga]GaCl3 was unable to show tumor images at any time point. The biodistribution results confirmed the PET imaging and blocking results.Conclusions: Our study successfully prepared [68Ga]DOTA-RRL with a high labeling yield under the optimized reaction conditions and demonstrated its potential role as a PET imaging agent for tumor-targeted diagnosis. [ABSTRACT FROM AUTHOR]

Abstract The structural stability and equation of state (EoS) of sodium formate (NaHCOO) up to ∼6 GPa have been investigated using in - situ synchrotron X-ray diffraction technique, at room temperature. The results indicate that sodium formate remained the monoclinic structure at high pressures and exhibited anisotropic compressibility, the b - and c -axes are more compressible than a -axis. The experimental pressure-volume data are fitted well with the third-order Birch-Murnaghan EoS, yielding a bulk modulus of B 0 = 26.0(1) GPa with its first pressure derivative B 0 ' = 4.5(7). The present results can provide some insight for better understanding of the structural stability of alkali and alkaline earth metal formates under high pressure. Highlights • High-pressure behaviors of sodium formate were investigated up to ∼6 GPa. • The isothermal bulk modulus is B 0 = 26.0(1) GPa and its first pressure derivative is B 0 ' = 4.5(7). • Axial compressibility shows obvious anisotropy, the crystallographic b - and c -axes are more compressible than a -axis. [ABSTRACT FROM AUTHOR]

Achieving sufficient energy transmission over a wide frequency range is a challenge which has restricted the application of many types of air-coupled ultrasonic transducers. Conventional transducer configurations such as the piezoelectric micromachined or flexural ultrasonic transducers can be considered as narrowband. This study reports a type of ultrasonic transducer, the wideband electromagnetic dynamic acoustic transducer (WEMDAT), which operates through a combination of electromagnetic induction and Lorentz force with dynamic behaviour of a micro-scale-thick conductive film. WEMDAT prototypes have been designed, fabricated, and tested, showing their compatibility with both low and high power inputs, operating efficiently as a wideband transmitter from 46.4 kHz to 144.6 kHz with a good directivity. The WEMDAT has also been shown to operate effectively as a wideband ultrasonic receiver through the measurement in a pitch-catch configuration. The WEMDAT prototypes possess an adjustable drive coil lift-off distance from the active membrane, providing flexibility for optimizing the sensitivity of the transducers for different input levels. The performance of the WEMDATs can be optimized, showing significant potential for air-coupled ultrasonic applications. [ABSTRACT FROM AUTHOR]

Highlights • Apply ensemble learning techniques to improve airline fuel burn prediction. • Propose a prediction interval based discretionary fuel estimation approach. • The new approach can achieve $61 million annual fuel savings for the study airline. • CO 2 emission can also be reduced by 428 million kg per year for the study airline. Abstract Reducing fuel consumption is a unifying goal across the aviation industry. One fuel-saving opportunity for airlines is the possibility of reducing discretionary fuel loading by dispatchers. In this study, we propose a novel discretionary fuel estimation approach that can assist dispatchers with better discretionary fuel loading decisions. Based on the analysis on our study airline, our approach is found to substantially reduce unnecessary discretionary fuel loading while maintaining the same safety level compared to the current fuel loading practice. The idea is that by providing dispatchers with more accurate information and better recommendations derived from flight records, unnecessary fuel loading and corresponding cost-to-carry could both be reduced. We apply ensemble learning techniques to improve fuel burn prediction and construct prediction intervals (PIs) to capture the uncertainty of model predictions. The upper bound of a PI can then be used for discretionary fuel loading. The potential benefit of this approach is estimated to be $61.5 million in fuel savings and 428 million kg of CO 2 reduction per year for our study airline. This study also builds a link between discretionary fuel estimation and aviation system predictability in which the proposed models can also be used to predict benefits from reduced fuel loading enabled by improved Air Traffic Management (ATM) targeting on improved system predictability. [ABSTRACT FROM AUTHOR]

In this work, we propose a strategy to design new deep‐ultraviolet (deep‐UV) nonlinear optical (NLO) materials through the combination of borate and phosphate NLO material genome. Accordingly, a series of borophosphates are predicted with very large energy bandgaps, strong second harmonic generation (SHG) effects, and moderate birefringence in the deep‐UV region. In particular, two novel fluoride borophosphates, PBO3F2 and PB3O6F2, are able to achieve the deep‐UV SHG laser output with shorter phase‐matching wavelengths (≈155 and 137 nm) than that of KBe2BO3F2 (KBBF, ≈161 nm). Further calculations show that these two structures are dynamically and thermodynamically stable, thus triggering possible synthesis, growth, and applications of them. The results attest that the proposed strategy is instructive and pave a comprehensive road map for us to discover new NLO crystals, especially in the borophosphate catalog with excellent deep‐UV phase‐matching capabilities beyond KBBF. [ABSTRACT FROM AUTHOR]

With the popularization of steel fiber reinforced concrete (SFRC), research on the packing of steel fiber-aggregate (F-A) mixtures has become a significant prerequisite for the mix design of SFRC. Although the compressible packing model (CPM) can be used to predict the packing density (PD) of F-A mixtures, its interaction coefficients are determined from the elementary particle classes without fibers (narrow particle size distribution), which limits the applicability of the CPM. In this study, after adding steel fibers to binary aggregate with wide particle size distribution, the PDs of steel fiber-binary aggregate (F-BA) mixtures were measured. The method of establishing interaction coefficients for F-A mixtures was modified, and the general formulas of interaction coefficients were proposed. The novel CPM model after comprehensive corrections of fiber disturbance parameter and interaction coefficients for F-A mixture was established. Compared with the conventional CPM, the prediction accuracy of novel CPM was greater. [Display omitted] • The effect of aggregate combinations and steel fiber combinations on packing density evolution was studied. • Corrections of fiber disturbance parameter and interaction coefficients in Compressible Packing Model were proposed. • The novel CPM was developed for packing density prediction of steel fiber-binary aggregate mixtures. • The novel CPM can be applied to aggregate with large particle classes. [ABSTRACT FROM AUTHOR]

• Ultrahigh through-plane thermal conductivity achieved by continuous carbon fibers. • Thermal-induced and slant slicing-induced flexibility. • Leakage proof capacity from polymer skeleton and carbon fiber arrays. • Novel thermal management capacity from high through-plane thermal conductivity and heat absorbed during phase change. With the rapid development of micro-nano electronics, thermally conductive materials with remarkable through-plane thermal conductivity (κ ⊥) and great flexibility are greatly urgent to effective thermal management. The fillers with high thermal conductivity (TC) are commonly assembled to achieve this target. However, the imperfect contact between the joint fillers will lead to high thermal resistance (R), hindering thermal transport. Herein, we fabricated thermal interface materials (TIMs) with ultra-high κ ⊥ (up to 168.4 W m−1 K−1) and adjustable flexibility by the combination of highly thermally conductive carbon fiber bundles (CF) and polymer encapsulated phase change materials (PCMs). The alignment of consecutive CF guarantees the continuity of thermal paths, greatly facilitating thermal transport. While the slantly slicing technique and softening effect of PCMs beyond phase transition temperature lead to an attenuated compression stress (1.6 MPa@10% strain with a CF loading of 50 wt%). What's more, the latent heat absorbed by PCMs is also conducive to thermal management. Thus, during a CPU temperature-control experiment, the application of as-prepared TIMs manifests a temperature decline of 33.9 °C of CPU. This work opens a new perspective to fabricating TIMs with ultrahigh κ ⊥ and low compression stress (σ) by the combination of thermally induced flexible matrix and the slantly slicing technique of aligned CFs. [ABSTRACT FROM AUTHOR]

• Atypical clinical features make it hard to identify VL in HLH in non-epidemic area. • VL is difficult to diagnose when traditional tests are ineffective, while mNGS is. • mNGS can be used as a detection method of HLH in children caused by rare pathogens. Visceral leishmaniasis-related hemophagocytic lymphohistiocytosis (VL-HLH) is a secondary hemophagocytic syndrome, which can be life-threatening, caused by leishmania and transmitted by infected sandflies. Rapid and accurate identification of leishmania is crucial for clinical strategies. Here, we report an infantile infection in a non-epidemic area of China. The infant was a 9.5-month-old girl with fever, pancytopenia and hepatosplenomegaly, which meet the HLH-2004 standard, and the negative gene results exclude congenital HLH. However, chemotherapy is ineffective and is accompanied by severe infection. Fortunately, she is diagnosed with VL-HLH (visceral leishmaniasis-related hemophagocytic lymphohistiocytosis), as leishmania is detected by next-generation meta-genome sequencing (mNGS) and quickly relieved after treatment with libosomal amphotericin B (L-AMB). mNGS can detect leishmania in pediatric HLH, and should be performed as a new detection for VL-HLH, particularly for infants, who may not respond to HLH-2004 regimen. [ABSTRACT FROM AUTHOR]

Purpose: CD38 is considered a potential biomarker for multiple myeloma (MM) and has shown a strong link with chronic lymphocytic leukemia due to high and uniform expression on plasma cells. In vivo evaluation of CD38 expression may provide useful information about lesion detection and prognosis of treatment in MM. In this study, immunoPET imaging with 89Zr-labeled daratumumab was used for differentiation of CD38 expression in murine lymphoma models to provide a potential non-invasive method for monitoring CD38 in the clinic.Methods: Daratumumab was radiolabeled with 89Zr (t1/2 = 78.4 h) via conjugation with desferrioxamine (Df). After Western blot (WB) was used to screen CD38 expression in five lymphoma cell lines, flow cytometry and cellular binding assays were performed to test the binding ability of labeled or conjugated daratumumab with CD38 in vitro. PET imaging and biodistribution studies were performed to evaluate CD38 expression after injection of 89Zr-Df-daratumumab. 89Zr-Df-IgG was also evaluated as a non-specific control group in the Ramos model. Finally, CD38 expression in tumor tissues was verified by histological analysis.Results: Using WB screening, the Ramos cell line was found to express the highest level of CD38 while the HBL-1 cell line had the lowest expression. Df-conjugated and 89Zr-labeled daratumumab displayed similar high binding affinities with Ramos cells. PET imaging of 89Zr-Df-daratumumab showed a high tumor uptake of up to 26.6 ± 8.0 %ID/g for Ramos at 120 h post-injection, and only up to 6.6 ± 2.9 %ID/g for HBL-1 (n = 4). Additionally, 89Zr-Df-IgG demonstrated a low tumor uptake in the Ramos model (only 4.3 ± 0.8 %ID/g at 120 h post-injection). Ex vivo biodistribution studies showed similar trends with imaging results. Immunofluorescence staining of tumor tissues verified higher CD38 expression of Ramos than that of HBL-1.Conclusions: The role of 89Zr-Df-daratumumab was investigated for evaluating CD38 expression in lymphoma models non-invasively and was found to be to a promising imaging agent of CD38-positive hematological diseases such as MM in future clinical applications. [ABSTRACT FROM AUTHOR]

With the growth of air traffic, airport surfaces are congested and air traffic operations are disrupted by the formation of bottlenecks on the surface. Hence, improving the efficiency and predictability of airport surface operations is not only a key goal of NASA’s initiatives in Integrated Arrival/Departure/Surface (IADS) operations, but also has been recognized as a critical aspect of the FAA NextGEN implementation plan. While a number of tactical initiatives have been shown to be effective in improving airport surface operations from a service provider’s perspective, their impacts on airlines’ scheduled block time (SBT) setting, which has been found to have direct impact on airlines’ on-time performance and operating cost, have received little attention. In this paper, we assess this impact using an econometric model of airline SBT combined with a before/after analysis of the implementation of surface congestion management (SCM) at John F. Kennedy International Airport (JFK) in 2010. Since airlines do not consider gate delay in setting SBT, we find that reduction in taxi-out time variability resulting from SCM leads to more predictable taxi-out times and thus decreases in SBT. The JFK SCM implementation is used as a case study to validate model prediction performance. The observed SBT decrease between 2009 and 2011 at JFK is 4.8 min and our model predicts a 4.2 min decrease. In addition, Charlotte Douglas International Airport (CLT) is used as an example to demonstrate how different surface operations improvements scenarios can be evaluated in terms of SBT reduction. [ABSTRACT FROM AUTHOR]

Background: Insulin-like growth factor-1 receptor (IGF-1R) is a well-studied oncogenic factor that promotes cell proliferation and energy metabolism and is overexpressed in numerous cancers including hepatocellular carcinoma (HCC). Aerobic glycolysis is a hallmark of cancer, and drugs targeting its regulators, including IGF-1R, are being developed. However, the mechanisms of IGF-1R inhibition and the physiological significance of the IGF-1R inhibitors in cancer cells are unclear. Materials and methods: Cell proliferation was evaluated by cell counting Kit-8 and colony formation assay. Western blot and real-time PCR were accordingly used to detect the relevant proteins, miRNA and gene expression. Luciferase reporter assays were used to illustrate the interaction between miR-342-3p and IGF-1R. The effect of miR-342-3p on glycolysis was determined by glucose uptake, ATP concentration, lactate generation, extracellular acidification rate and oxygen consumption rate assays. In vivo, subcutaneous tumor formation assay and PET were performed in nude mice. Results: In this study, we demonstrate that by directly targeting the 3'-UTR (3'-untranslated regions) of IGF-1R, microRNA-342-3p (miR-342-3p) suppresses IGF-1R-mediated PI3K/AKT/GLUT1 signaling pathway both in vitro and in vivo. Through suppression of IGF-1R, miR-342-3p dampens glycolysis by decreasing glucose uptake, lactate generation, ATP production, and extracellular acidification rate (ECAR), and increasing oxygen consumption rate (OCR) in hepatoma cells. Importantly, glycolysis regulated by miR-342-3p is critical for its regulating HCC growth both in vitro and in vivo. Conclusion: Our findings provide clues regarding the role of miR-342-3p as a tumor suppressor in liver cancer mainly through the inhibition of IGF-1R. Targeting IGF-1R by miR-342-3p could be a potential therapeutic strategy in liver cancer. [ABSTRACT FROM AUTHOR]

Flexural ultrasonic transducers are principally used as proximity sensors and for industrial metrology. Their operation relies on a piezoelectric ceramic to generate a flexing of a metallic membrane, which delivers the ultrasound signal. The performance of flexural ultrasonic transducers has been largely limited to excitation through a short voltage burst signal at a designated mechanical resonance frequency. However, a steady-state amplitude response is not generated instantaneously in a flexural ultrasonic transducer from a drive excitation signal, and differences in the drive characteristics between transmitting and receiving transducers can affect the measured response. This research investigates the dynamic performance of flexural ultrasonic transducers using acoustic microphone measurements and laser Doppler vibrometry, supported by a detailed mechanical analog model, in a process which has not before been applied to the flexural ultrasonic transducer. These techniques are employed to gain insights into the physics of their vibration behaviour, vital for the optimisation of industrial ultrasound systems. [ABSTRACT FROM AUTHOR]

Lactate dehydrogenase A (LDHA), a key enzyme regulating aerobic glycolysis, is overexpressed in many human cancers, and correlates with poor clinical outcomes. Aerobic glycolysis is a hallmark of cancer, and drugs targeting its regulators, including LDHA, are being developed. However, the mechanisms of LDHA inhibition and the physiological significance of the LDHA inhibitors in cancer cells are unclear. Here, we show that microRNA-30a-5p (miR-30a-5p) suppresses LDHA expression by directly targeting its 3′-UTR. Through inhibition of LDHA, miR-30a-5p dampens glycolysis by decreasing glucose uptake, lactate production, ATP generation, and extracellular acidification rate (ECAR), and increasing oxygen consumption rate (OCR) in breast cancer cells. Importantly, glycolysis regulated by miR-30a-5p is critical for its regulating breast tumor growth and metastasis both in vitro and in vivo. In breast cancer patients, miR-30a-5p expression is negatively correlated with LDHA expression. Moreover, patients who had increased glucose uptake in tumors assessed by PET scans showed decreased miR-30a-5p expression and increased expression of LDHA. Our findings provide clues regarding the role of miR-30a-5p as a tumor suppressor in breast cancer through the inhibition of LDHA. Targeting LDHA through miR-30a-5p could be a potential therapeutic strategy in breast cancer. [ABSTRACT FROM AUTHOR]

Shear horizontal (SH) waves are widely used in the non-destructive evaluation and structural health monitoring fields. Conventional periodic permanent magnet electromagnetic acoustic transducers (PPM EMAT) can generate a single SH wave mode, which propagates in both forward and backward directions. Generation in a single direction is usually preferred to ease signal interpretation and increase inspection reliability. Recently, we have proved that a single, either fundamental or high-order, SH wave mode can be unidirectionally generated using a dual PPM EMAT, with carefully designed driving signals. Distinct SH modes present different applicability due to their particular response to features in the structure, such as defects. Hence, unidirectional generation of two different SH modes simultaneously with a dual-array transducer is investigated in this paper. The selectivity of wave modes and the selectivity of the propagation direction are studied by combining pure wave mode excitability with the superposition of optimal excitation signals for unidirectional generation, addressed in the frequency–wavenumber domain. Excitation signals for optimal and simultaneous generation of the SH0 and SH1 modes propagating in the same direction or in opposite directions have been designed. Experiments on an aluminium plate have demonstrated that the two wave modes can be effectively simultaneously generated with only one dual-array transducer and the propagation direction of each wave mode can be flexibly controlled using the designed excitation signals. • A single dual-array transducer excites distinct unidirectional waves simultaneously. • Pure wave excitation and direction are addressed in the frequency–wavenumber domain. • Superposition of optimal excitation signals ensures simultaneous wave generation. • A dual PPM-EMAT simultaneously generated SH0 and SH1 modes in distinct directions. • The generation direction of each wave mode can be conveniently controlled. [ABSTRACT FROM AUTHOR]

Steel fiber can significantly improve the tensile strength, toughness, and crack resistance of concrete matrix, but there is limited research on the packing of single steel fiber-aggregate (SF-A) and hybrid steel fiber-aggregate (HF-A) mixtures. To investigate the effect of steel fibers on the packing of aggregates, the loosely-packed packing density (PD) of 36 SF-A mixtures and 36 HF-A mixtures was measured via the high-rigidity container. The results indicated that the PD always decreased with increasing fiber volume regardless of single or hybrid steel fibers and the size ratio of steel fiber to aggregate particle was a crucial parameter affecting this lowering effect. Moreover, a novel prediction model considering the relative size of fiber and aggregate as key factors was developed and the synergistic effect on aggregates by hybrid fibers was also incorporated into the model. Prediction errors less than 1% were evaluated after calibrating the model parameters. [Display omitted] • The packing rules of the steel fiber-aggregate mixtures are clarified. • A synergistic effect of hybrid steel fibers on aggregate is proposed. • The calculation method for the fiber disturbance factor is modified. • A prediction model of packing density for single and hybrid steel fiber-aggregate mixtures is presented. [ABSTRACT FROM AUTHOR]

• Effective and low-consumption finishing strategy for multifunctional stainless steel mesh and sponges. • Superhydrophobic coating with micro/nano structures is rationally constructed without organic solvents. • Rational water-based aza-Michael addition reaction coating strategy realizes on-demand special wettability. Superhydrophobic porous materials are widely used in oil-water separation due to their water-blocking and oil-passing properties. However, the preparation of most superhydrophobic porous materials is generally energy-intensive and must be performed using organic solvents. In this study, we describe a straightforward and cost-effective strategy for fabricating superhydrophobic coatings on nanosized soil particle-modified stainless steel mesh (SSM). The coating is prepared via the aza-Michael reaction of stearyl acrylate and melamine-urea–formaldehyde (MUF) resin catalysed by methyl cyclodextrin in water. Superhydrophobic meshes with water contact angles (WCAs) exceeding 150° are obtained, exhibiting extraordinary water repellency. The superhydrophobic mesh also effectively prevents surface contamination, creating a self-cleaning surface that is both waterproof and dustproof. Most importantly, the superhydrophobic mesh presents excellent oil separation performance for oil-water mixtures of various compositions, maintaining extremely high separation efficiency (>98%) even after 80 cycles. Additionally, we successfully apply this strategy to the preparation of superhydrophobic melamine sponges with excellent oil adsorption capacity (17.6–44.2 g/g). This innovative study provides an effective strategy for designing biomimetic superhydrophobic surfaces and is a promising development in the field of environmentally friendly oil-water separators. [ABSTRACT FROM AUTHOR]

With the rapid development of the electronics industry, there is a growing demand for packaging materials that possess both high thermal conductivity (TC) and low electrical conductivity (EC). However, traditional insulating fillers such as boron nitride, aluminum nitride, and alumina (Al2O3) have relatively low intrinsic TC. When graphene, which exhibits both superhigh TC and EC, is used as a filler to fill epoxy resin, the TC of blends can be much higher than that of blends containing more traditional fillers. However, the high EC of graphene limits its application in cases where electrical insulation is required. To address this challenge, a method for coating graphene sheets with an in situ grown Al2O3 layer has been proposed for the fabrication of epoxy-based composites with both high TC and low EC. In the presence of a cationic surfactant, a dense Al2O3 layer with a network structure can be formed on the surface of graphene sheets. When the total content of Al2O3 and graphene mixed filler reached 30 wt%, the TC of the epoxy composite reached 0.97 W m−1 K−1, while the EC remained above 1011 Ω·cm. Finite element simulations accurately predicted TC and EC values in accordance with experimental results. This material, with its combination of high TC and good insulation properties, exhibits excellent potential for microelectronic packaging applications. [ABSTRACT FROM AUTHOR]

Scheduled block time (SBT) is the time between gate departure and gate arrival assumed by airlines for use in published timetables and operations planning. SBT setting has critical impacts on airlines’ operating cost and on-time performance. Air carriers regularly update their SBTs to respond to changing operating conditions and evolving business strategies. Most existing studies have focused on investigating the impact of SBT on on-time performance or predicting SBT based on historical performance and market characteristics. However, the dynamics of adjusting SBT, which may allow deeper understanding about the trade-offs airlines make between SBT and on-time performance, have been rarely studied. In this paper, we assume that SBT adjustment choices reveal preferences. Based on airlines’ practice in setting SBT, hypothetical SBT scenarios and their corresponding on-time performance profiles are re-constructed to mimic the situations faced by airline schedulers. This enables us to infer how airlines trade-off between SBT, on-time arrivals, and earliness. By using correlated mixed logit models, we find that our five study airlines are willing to increase SBT from 0.38 to 0.54 min to increase on-time performance by 1%. We also find that both on-time performance and early arrival are valued by airlines, but the former is considerably more valuable. The estimated models can also be used to predict airlines’ SBT adjustments in response to changes in operational performance. [ABSTRACT FROM AUTHOR]

A new schiff-base receptor L based on naphthalimide had been investigated as a selective and sensitive chemosensor for Al 3+ in CH 3 OH. Upon addition of Al 3+ , L showed a 39-fold enhancement at 508 nm with colorimetric and fluorometric dual-signaling response which might be induced by the integration of ICT and CHEF. A 1:1 stoichiometry for the L -Al 3+ complex was formed with an association constant of 1.62×10 4 M −1 , and the limit of detection for Al 3+ was determined as 7.4 nM. In addition, the potential utility of L in sensing Al 3+ was also examined in real water samples. [ABSTRACT FROM AUTHOR]

A new chloride borate, Ba 1.31 Sr 3.69 (BO 3 ) 3 Cl, was obtained when exploring potential phosphor materials. It belongs to orthorhombic system, Pnma space group, with cell parameters of a = 6.965(1) Å, b = 16.546(3) Å, c = 9.557(1) Å and Z = 4. Ba 5- x Sr x (BO 3 ) 3 Cl ( x = 0, 0.5, …to 5) was synthesized and the cell volumes of the solid solutions were obtained by Rietveld refinement. Detailed structure description of Ba 1.31 Sr 3.69 (BO 3 ) 3 Cl was conducted and the structure comparison between Ba 1.31 Sr 3.69 (BO 3 ) 3 Cl and M 5 (BO 3 )X (M = Ba or Sr, X = Cl or F) was illustrated. In Ba 1.31 Sr 3.69 (BO 3 ) 3 Cl, there are hexagonal tunnels extending along a -axis, which is the main feature of apatite family compounds. The density functional theory calculation suggested that in Ba 1.31 Sr 3.69 (BO 3 ) 3 Cl space group Pnma is more energy favourable than C 222 1 . DSC-TG showed that Ba 1.31 Sr 3.69 (BO 3 ) 3 Cl is stable up to 950 °C and Raman and Infrared spectroscopy demonstrate the existence of planar (BO 3 ) 3- in the structure. [ABSTRACT FROM AUTHOR]

The main disadvantage of electromagnetic acoustic transducers (EMATs) is their inefficiency in generating ultrasound. A new design of Rayleigh-wave EMAT is proposed with improved ultrasonic generation efficiency on non-ferromagnetic materials. The new EMAT's magnet is narrower than the meander-line coil used in the transducer and the coil itself has an uneven distribution of conductors. The principle of the new design is informed by finite element simulations, which show that the EMAT generates Rayleigh waves more efficiently by taking advantage of both horizontal and vertical magnetic fields of the magnet simultaneously. Experimental measurements verify that the maximum amplitude of the ultrasonic signal generated by the new design of EMAT working under a pulse-echo configuration has been enhanced by 90%, when compared to conventional designs. [ABSTRACT FROM AUTHOR]

Metal sulfides with diamond-like (DL) structures are systematically investigated in this study for nonlinear optical (NLO) applications in the mid-infrared (mid-IR) spectral region. All the selected materials are characterized by a 3D framework connected by various sulfide tetrahedral units, such as [PS 4 ], [SiS 4 ], [GeS 4 ], [GaS 4 ], [InS 4 ], [CdS 4 ], [ZnS 4 ], [LiS 4 ], and [AgS 4 ]. The linear and nonlinear optical properties of these materials are analyzed on the basis of first-principles calculations. It is concluded that it is relatively easy to achieve good balance between the bandgap and the NLO effect. Additionally, moderate birefringence Δn (∼0.03–0.10) is required for practical mid-IR NLO applications. In particular, several metal sulfides with normal DL and defect DL structures, exhibiting superior mid-IR NLO properties, are highlighted. These provide an instructive guide for the design and discovery of new materials with good mid-IR NLO performance. [ABSTRACT FROM AUTHOR]

Reconfigurability is one of the most critical properties of nanophotonic systems and, consequently, methods for enabling a significant degree of functionality are highly sought after. However, dynamically responsive control in top-down fabricated photonic structures often requires extreme conditions and yields moderate modulation capability. In sharp contrast to top-down methods, directed self-assembly of micro- and nanoparticles offers a distinct avenue for reconfigurable photonics. In the present work, gold nanowire lattices are formed via electric field directed assembly in order to take advantage of their collective optical properties. The lattices are reconfigured on-demand between two different functional states, in the form of broadband polarizers. By selectively switching the electric field between two orthogonal electrode pairs, a maximum transmission contrast of ≈50% is observed in the near-infrared regime. Moreover, the reconfigurable transmission spectra, which are highly dependent on the nanowire size and electric field conditions, are reversible. The demonstrated proof-of-concept nanowire lattice polarizer provides potential for electrically reconfigurable photonic devices such as ultra-compact polarization components, electro-optic switches, and on-chip modulators. [ABSTRACT FROM AUTHOR]

With the implementation of the western development strategy, large areas in western China are experiencing rapid industrialization and urbanization phases. Simultaneously, increasing energy consumption linked to CO 2 emissions is becoming a serious problem. The stochastic impacts by regression on population, affluence, and technology model and the random parameters model were developed to assess and quantify the strength of the relationship between CO 2 emissions that are attributed to energy consumption and their major drivers (i.e., population, economy, and technology). The Ningxia Hui Autonomous Region, which is a typical region in western China with low energy efficiency and rapid economic growth, was selected as an example. This study determined CO 2 emissions attributed to energy consumption from 1991 to 2011, and assessed the effects of the major drivers of CO 2 emissions at the county level. The following results were obtained. (1) The CO 2 emissions of Ningxia increased rapidly throughout the study period. (2) Increasing gross domestic product (GDP) per capita, urban employment, and the contribution to GDP of secondary industries would promote CO 2 emissions. By contrast, increasing the growth of the per capita annual disposable income of rural households, the contribution to GDP of tertiary industries, and population density would restrain CO 2 emissions. (3) The county-level heterognerity was found to be significant which suggests adopting a uniform policy might not be optimal. Finally, the study method, effects of CO 2 emission factors, and policy suggestions could also be applied to other provinces and autonomous regions in western China because of the similar characteristics of these areas such as vast lands, rich resources, and low development level. [ABSTRACT FROM AUTHOR]

[Display omitted] • Magmatism formed during the initial stage (ca. 480Ma) and advanced stage (ca. 450Ma) of exhumation of subducted continental crust have been recognized in South Altyn western China. • Two stages of magmatism exhibits evidence for the partial melting of subducted continental crust during differential exhumation process of South Altyn in Palaeozoic. The early Palaeozoic continental subduction–collisional belt in South Altyn (SA) western China distributes a large amount of (ultra)-high-pressure ((U)HP) metamorphic and granitic rocks associated with subduction, collision, and exhumation. In this study, four granitic rocks were collected from Bashenwake located in eastern SA. The ages of the garnet-bearing alkali-feldspar granite (GAFG), garnet-bearing granitic gneiss (GGG), alkali-feldspar granite (AFG), and syenogranite (SG) are 458.0 ± 4.1, 483.0 ± 4.1, 450.0 ± 2.4, and 482.0 ± 4.9 Ma, respectively. Whole-rock major and trace elements and Sr–Nd–Pb isotope, and zircon Hf isotope compositions for all samples exhibit characteristics of a continental crustal source. Based on partial melting modeling, the source temperature of the GGG, GAFG, AFG and SG was concluded as 750–780 °C, 730–760 °C, 730–770 °C and ca. 800 °C, respectively. The source pressure was estimated as ca. 0.8 GPa for the GGG, GAFG and AFG, and ca. 1.2 GPa for SG. Combined with studies on (U)HP metamorphic rocks in SA, this study reveals that GGG is formed by metamorphism while SG is formed from partial melting of upper crustal rocks heated by upwelling mantle during the initial stage of exhumation (ca. 480 Ma) of subducted continental crust in SA. During further stage of exhumation of the subducted continental crust at ca. 450 Ma, the GAFG and AFG were formed from partial melting of GGG as a result of decreased pressure and further mantle upwelling. Consequently, the exhumation age of subducted continental crust in eastern SA is ca. 30 Myr earlier than that in western SA. Thus, the geochronology and petrogenesis of four granitic samples in this study exhibit one of very few evidence for partial melting of subducted continental crust during the exhumation and also provide magmatism exhibits evidence for the differential exhumation model of eastern SA in Palaeozoic. [ABSTRACT FROM AUTHOR]

A new chemosensor L based on the naphthalimide moiety was synthesized and characterized. L exhibited the high selectivity and sensitivity for Al 3 + in CH 3 OH, along with colorimetric and fluorometric dual-signaling responses based on the joint contribution of the ICT and CHEF processes. A 1:1 stoichiometry for the L -Al 3 + complex was formed with an association constant of 7.6 × 10 4 M − 1 , and the limit of detection for Al 3 + was determined as 6.9 μM. In addition, L was successfully applied to the determination of Al 3 + in real water samples. [ABSTRACT FROM AUTHOR]

A superhydrophobic coating composed of epoxy on the bottom and siloxane-modified silica on the top was prepared by employing the scraping and spraying methods. The superhydrophobic coating possesses excellent mechanical properties, is superhydrophobic (water contact angle, WCA = 164.3°), and has low adhesion. The long-term corrosion resistance of the epoxy coating and the superhydrophobic coating in a 3.5 % NaCl solution and hydrogen sulfide environment was assessed using electrochemical impedance spectroscopy (EIS), polarization curve analysis, immersion testing, and X-ray diffraction (XRD). Test results indicate that the superhydrophobic coating has excellent anti-corrosion capability in an H 2 S environment for 50 days and in a 3.5 % NaCl solution for 60 days. This is of great significance for developing the potential applications of superhydrophobic coatings in H 2 S environments. [Display omitted] • Epoxy resin and superhydrophobic surface combination for carbon steel substrate protection. • The coating showed anticorrosive effect in 3.5 % sodium chloride solution. • Superhydrophobic surface has excellent corrosion resistance in H 2 S environment of alternating temperatures and humidities. [ABSTRACT FROM AUTHOR]

Phase change materials (PCMs) are potential candidates in passive thermal regulation and energy storage fields due to their high latent heat capacity around phase transition temperature. However, the leakage problem and low thermal conductivity are two obstructive factors for the extended application of PCMs. Herein, a series of paraffin@silicon dioxide microcapsules (Pa@SiO 2)/graphene sheets (GS)/silicone rubber (SR) phase change composites (PCCs) were prepared. It is found that the inorganic SiO 2 shell is conducive to enhancing the thermal conductivity of PCCs and the double encapsulation by the SiO 2 shell and SR skeleton can restrict the leakage of liquid Pa during phase transition. With a Pa@SiO 2 content of 70 wt%, the PCCs have a high latent heat of 126.1 J/g and enhanced thermal conductivity of 0.37 W m−1 K−1, which is 131.25% higher compared to that of pure SR. In addition, the introduction of graphene sheets further boosts the thermal conductivity of PCCs to 2.69 W m−1 K−1. The obtained PCCs lead to a surprising temperature decline of nearly 35 °C of a commercial lithium-ion battery during a high discharge rate (7.4 C). This work provides an efficient route to fabricate microcapsules-based PCCs for passive thermal regulation. [Display omitted] [ABSTRACT FROM AUTHOR]

The article focuses on the biodiversity and the geochemical signature of the Beishan region in the Central Asian Orogenic Belt during the Late Carboniferous‐Early Permian period.

As a symbolic ceramic oxide, the reaction of SiO 2 as an insulating layer with the Fe–Si–Al/SiO 2 soft magnetic composites (SMCs), substrate during heat treatment, as well as the resulting microscopic phase transition of the core–shell structure and its influence on the magnetic properties, are worth investigating. In this study, based on the successful synthesis of Fe–Si–Al based SMCs using fluidised chemical vapour deposition combined with an electric hot–press sintering method, the evolution of the insulating layers was investigated under different heat–treatment temperatures and closely linked to the magnetic performance of the composites. During heat treatment at high temperatures, the formation of high–resistivity oxides (Al 2 O 3) after heat treatment results in a low inter–particle eddy current loss, while excessive temperature causes disintegration of the core–shell heterostructure. This leads to a discernible increase in eddy current and hysteresis losses and a decrease in permeability and resistivity. The SMCs had an Ms of 115.8 emu/g, a resistivity of 6.86 mΩ cm, and a hysteresis loss of 56.3 kW/m3 at 10 mT and 100 kHz when heat-treated at 1373 K for 120 min, which was the best among all samples. This research provides a novel approach to building SMCs with inorganic ceramic insulating layers and a comprehensive understanding of the relationship between the heat–treatment process parameters, microstructure, and magnetic properties which is highly significant for industrial production. [Display omitted] [ABSTRACT FROM AUTHOR]

• Novel adaptation of transformers for handwriting recognition tasks, bypassing recurrent neural nets. • Competitive results achieved in low resource scenario with synthetically pretrained model. • Extensive ablation and comparative studies conducted to understand and modify transformer properly for HTR. • Implicit language modelling ability proved. • The state-of-the-art performance achieved on public IAM dataset. The advent of recurrent neural networks for handwriting recognition marked an important milestone reaching impressive recognition accuracies despite the great variability that we observe across different writing styles. Sequential architectures are a perfect fit to model text lines, not only because of the inherent temporal aspect of text, but also to learn probability distributions over sequences of characters and words. However, using such recurrent paradigms comes at a cost at training stage, since their sequential pipelines prevent parallelization. In this work, we introduce a novel method that bypasses any recurrence during the training process with the use of transformer models. By using multi-head self-attention layers both at the visual and textual stages, we are able to tackle character recognition as well as to learn language-related dependencies of the character sequences to be decoded. Our model is unconstrained to any predefined vocabulary, being able to recognize out-of-vocabulary words, i.e. words that do not appear in the training vocabulary. We significantly advance over prior art and demonstrate that satisfactory recognition accuracies are yielded even in few-shot learning scenarios. [ABSTRACT FROM AUTHOR]

Array transducers are commonly used to generate several types of waves, such as ultrasonic guided waves. They consist of a series of periodic wave source elements, and thus define a nominal or dominant wavelength of generated waves. A common approach to generating waves in a single direction is to use two identical wave sources, or two arrays of sources forming a dual-array transducer, that are separated by a quarter wavelength. Then, one source is activated a quarter of a time period after the other. In this way, constructive interference arises in one direction, whilst destructive interference arises in the opposite direction, making the total wave source unidirectional. This principle assumes that the frequency content of the generated wave is monochromatic. When there is some frequency bandwidth to the wave generated, such as with finite-length pulses, one cannot satisfy simultaneously constructive and destructive interference in opposite directions with dual-array transducers. For a non-dispersive wave mode, ideal destructive interference for pulsed waveform is obtained if one of the sources is inverted relative to the other, so that, in theory, complete cancellation can be achieved. Moreover, most guided wave modes are dispersive, meaning that, different frequencies propagate at different phase speeds. This limits the amount of wave cancellation in one direction and constructive interference in the other. Here, we describe the operation of the dual-array transducer in the frequency–wavenumber domain and use it to propose two new excitation methods, based on a frequency-dependent phase-shift strategy, that is designed through the dispersion relationship of the wave mode of interest. These provide ideal constructive or destructive interferences for dispersive waves, and achieve optimal unidirectional generation behaviour for dispersive wave modes. The new methods were experimentally assessed with shear horizontal ultrasonic waves, generated by a dual periodic permanent magnet electromagnet acoustic transducer. The optimal excitation signal yielded up to 30 dB unidirectionality, when generating the dispersive SH1 wave mode in an aluminium plate. • Unidirectional wave generation is addressed in the frequency–wavenumber domain. • Usual time-delay excitation methods were proved not appropriate for dispersive waves. • We propose a method that optimally generates dispersive waves unidirectionally. • A dual PPM-EMAT was used to generate shear horizontal waves in a single direction. • About 30 dB unidirectionality was achieved for the dispersive SH1 mode experimentally. [ABSTRACT FROM AUTHOR]

Array transducers can allow wavelength and frequency selectivity and can be used to generate different types of waves, such as ultrasonic bulk or guided waves. Dual-array transducers consist of two interlaced arrays, where the elements of each array are electrically connected. Therefore, by driving each array with a pair of phased pulses one can achieve a degree of wave generation control that allows unidirectional generation, unlike single array transducers that generate waves in both 0° and 180° directions with respect to the array's longitudinal axis. In this paper, we present a one-dimensional analytical model to determine the ultrasonic waves generated by dual-array transducers based on the excitability of the array in the frequency–wavenumber domain, the so-called operation region, determined by the joint spatial and temporal spectrum of the dual-array. We further exploited it to analyse the effectiveness of unidirectional generation with time-delayed excitation signals that provide ideal constructive or destructive interferences. The model also provides the time-domain received waveforms, which were compared to experimentally generated shear-horizontal ultrasonic guided waves, with a dual periodic permanent magnet array electromagnetic acoustic transducer, showing very good agreement. The adequate selection of the excitation signal allowed one to obtain up to about 40 dB unidirectionality experimentally. • Dual-array transducers are modelled in the frequency–wavenumber domain. • The interference mechanism of two types of time-delayed pulses is analysed. • A Dual-PPM EMAT is used to experimentally generate SH guided waves unidirectionally. • Model-predicted time-domain signals and experimental ones show excellent agreement. • About 40 dB unidirectionality was achieved with the ideal excitation pulses. [ABSTRACT FROM AUTHOR]

Objective: To describe a new modification of the Koyanagi technique for the one-stage repair of severe hypospadias and its short-term outcomes.Patients and Methods: Our modified Koyanagi technique was performed in 24 patients with severe hypospadias between February 2012 and January 2015. The age of the patients ranged from 1.9 to 11.9 years (mean = 3.5 years). The flap design was similar to the Koyanagi technique, but our modified technique highlighted the following points: after the chordee was completely corrected, the urethral plate was recreated using foreskin, and then a U-shaped incision was made on the original and recreated urethral plate (as in the Duplay technique); a pedicled flap of the tunica vaginalis or scrotal dartos was used for additional coverage of the neourethra.Results: The operation time lasted from 120 to 150 minutes (mean = 140 minutes). There were 5 patients (20.8%) who developed complications: 4 patients (16.7%) developed a fistula and 1 patient (4.2%) developed dehiscence of the urethra. There were no reported urethral strictures, meatal stenosis, or urethral diverticula. The complications in the 5 patients were successfully addressed with secondary repair, and all patients achieved satisfactory cosmetic and urethral functional results.Conclusion: The modified Koyanagi technique simplified the operation and better preserved the blood supply to the flap. The additional coverage of the neourethra using a pedicled flap of the tunica vaginalis or scrotal dartos significantly decreased the rate of fistula formation. This technique is highly suitable for the one-stage repair of severe hypospadias with penoscrotal transposition. [ABSTRACT FROM AUTHOR]

Bicycling and walking are gaining popularity for both commuting and recreation. However, when faced with limited right-of-way width, many transportation agencies find it impractical to designate separate space for bicyclists in urban roadway corridors, instead devoting their limited funds to other projects. As a result, some bicyclists – feeling threatened by motor vehicles – use sidewalks for at least part of their trip. Laws governing bicyclist use of sidewalks are not consistently enforced in various cities and countries. Pedestrian-bicycle shared space has rarely been studied from a pedestrian's perspective in an urban context. Therefore, gaining a better understanding of the factors that influence pedestrian attitudes toward sharing a sidewalk with bicyclists can be useful in evaluating shared space strategies and guiding investments in bicycle facilities. Using the responses of 114 persons to 15 carefully constructed 60-s video clips of urban sidewalks in four Chinese cities, this study characterizes pedestrian attitudes regarding sharing sidewalks with bicycles under different sidewalk configurations. By estimating a random parameters ordered probability model (to account for unobserved heterogeneity across respondents), we found pedestrians who wanted a “safe distance” greater than 1.5 meters were more likely to possess a less tolerant attitude. Attitudes of pedestrians toward bicyclists on sidewalks also depend on the presence or absence of dedicated bicycle facilities. The effects of other significant factors are also quantified in this paper. Implications for policy makers in evaluating shared-space strategy can be drawn from this empirical study. [ABSTRACT FROM AUTHOR]

Greater understanding of the topological evolution characteristics of the supply side of urban transport systems could help urban planners and policy makers uncover patterns of both city growth and road development. This paper examines the road network topological evolution characteristics of a unique government-oriented development district, Shanghai Pudong New District, from 1995 to 2007, where a road-name–based dual approach is adopted to capture the homogeneity and functional continuity of different segments. The urban road network is found to evolve from a broad-scale system to a scale-free system driven by the government interventions. A generalized extreme value distribution is utilized to provide a general form for the road network topological evolution model with a good fit. This scale-free road network has shown to be effective in supporting economic development. This paper offers a new perspective that describes the patterns of topological evolution characteristics for transportation planners regarding network design and urban planning in the long run. [ABSTRACT FROM AUTHOR]

An efficient synthesis of dihydrobenzo[c]phenanthridinones was achieved by utilizing an indium(0)-mediated intramolecular cyclization reaction under ligand- and base-free conditions. A variety of functional groups were tolerated in the present protocol. [ABSTRACT FROM AUTHOR]

A new noncentrosymmetric borate, Na3Y3(BO3)4, was grown in the Na2O–B2O3–NaF flux system. Its open-framework structure features a large hexagonal tunnel (5.92 Å in diameter), which is extremely rare in borates. First-principles calculations on its kinetic stability and optical properties were performed. [ABSTRACT FROM AUTHOR]

Podocalyxin-like protein (PODXL) is a member of CD34 family proteins. It is the protein that carries many post-translational epitopes responsible for various pluripotent surface markers including TRA-1-60, TRA-1-81, GCTM2, GP200, and mAb84. However, PODXL has not attracted the attention of stem cell biologists. Here, we report several features of PODXL mRNA and protein in pluripotent stem cells. Similar to the modification-dependent pluripotent epitopes, PODXL transcripts and carrier protein are also features of pluripotency. PODXL is highly expressed in early human embryos from oocytes up to four-cell stages. During reprogramming of human cells to pluripotency, in contrast to TRA-1-60 and TRA-1-81, PODXL is activated by KLF4 at a very early time of reprogramming. Although TRA-1-60 and TRA-1-81 are completely lost upon differentiation, a residual PODXL+ population exists even after extended differentiation and they were identified by the universal human PODXL epitope 3D3. Unlike TRA-1-60 and TRA-1-81 epitopes that are unique to primate pluripotent stem cells (PSCs), PODXL carrier protein can be used as a murine surface marker. Most importantly, antibody to 3D3 epitope causes massive necrosis and apoptosis of human PSCs (hPSCs). We suggest that 3D3 antibody could be employed to eliminate the tumorigenic pluripotent cells in hPSC-derived cells for cell transplantation. [ABSTRACT FROM AUTHOR]

Purpose We investigated whether a 99m Tc radiolabeled anti-miRNA-155 oligonucleotide (AMO-155) could visualize the expression of miR-155 in multiple kinds of tumors in vivo . Methods AMO-155 was chemically synthesized and modified with 2′- O -methyl (2′-OMe) and phosphorothioate (PS). It was radiolabeled with 99m Tc via the conjugation with NHS-MAG3 at 5′ end. The characterization of radiolabeling and serum stability was evaluated using high performance liquid chromatography (HPLC) and agarose gel electrophoresis. The expression of C/EBPβ, one of the miR-155 target proteins, was assessed using Western blot. The cellular uptake and delivery of AMO-155 was further evaluated in tumor cells. 99m Tc-AMO-155 was tested in vivo in multiple tumor models, including miR-155 over-expressed and low-expressed tumor models. Finally, biodistribution of 99m Tc-AMO-155 was evaluated. Results 99m Tc-AMO-155 was prepared with high yield and radiochemical purity. It showed high stability in fresh human serum for 10 h. 99m Tc-AMO-155 displayed comparable capacity as unlabeled AMO-155 to increase the expression of C/EBPβ protein in MCF-7 cells. 99m Tc-AMO-155 showed an increased radioactive uptake in MCF-7 cells after 8 h of incubation, whereas no change of 99m Tc-pertechnetate uptake was observed. Carboxyfluorescein (FAM) labeled AMO-155 had higher fluorescent delivery than Control in HeLa and HepG2 cells by confocal microscopy. In miR-155 over-expressed tumor models, 99m Tc-AMO-155 showed significantly higher tumor accumulation than 99m Tc-Control. Furthermore, 99m Tc-AMO-155 was capable of discriminating between MCF-7 and MDA-MB-231 tumors based on their expression of miR-155. Conclusions Our study successfully prepared and proved 99m Tc-AMO-155 as a prospective imaging agent for the noninvasive visualization of miR-155 expression in vivo . [ABSTRACT FROM AUTHOR]

A new protocol for total synthesis of natural product frutinone A was accomplished in three steps by using inexpensive 2'-hydroxyacetophenone as starting material. The key intermediate 3-(2-chlorobenzoyl)-4-hydroxycoumarin was synthesized in one pot through Baker-Venkataraman rearrangement of 2-acetylphenyl 2-chlorobenzoate followed by introduction of methyl chloroformate under basic conditions. Then, base-promoted intramolecular nucleophilic substitution reaction of 3-(2-chlorobenzoyl)-4-hydroxycoumarin provided frutinone A in excellent yield. The synthetic route features good yield, transition metal-free and mild reaction conditions, and high tolerance for functionality, thereby allowing easy substitutions around the frutinone A core. [ABSTRACT FROM AUTHOR]

Ammonia-borane (AB) is a promising chemical hydrogen-storage material However, the development of real-time, efficient, controllable, and safe methods for hydrogen release under mild conditions is a challenge in the large-scale use of hydrogen as a long-term solution for future energy security. A new class of low-cost catalytic system is presented that uses nanostructured Ni2P as catalyst, which exhibits excellent catalytic activity and high sustainability toward hydrolysis of ammonia-borane with the initial turnover frequency of 40.4mol(H2) mol(Ni2P) -1 min-1 under air atmosphere and at ambient temperature. This value is higher than those reported for noble-metal-free catalysts, and the obtained Arrhenius activation energy (Ea = 44.6 kJmol-1) for the hydrolysis reaction is comparable to Ru-based bimetallic catalysts. A clearly mechanistic analysis of the hydrolytic reaction of AB based on experimental results and a density functional theory calculation is presented. [ABSTRACT FROM AUTHOR]

Ammonia–borane (AB) is a promising chemical hydrogen-storage material. However, the development of real-time, efficient, controllable, and safe methods for hydrogen release under mild conditions is a challenge in the large-scale use of hydrogen as a long-term solution for future energy security. A new class of low-cost catalytic system is presented that uses nanostructured Ni2P as catalyst, which exhibits excellent catalytic activity and high sustainability toward hydrolysis of ammonia–borane with the initial turnover frequency of 40.4 mol(H2) mol(Ni2P)-1 min-1  under air atmosphere and at ambient temperature. This value is higher than those reported for noble-metal-free catalysts, and the obtained Arrhenius activation energy (Ea=44.6 kJ mol-1) for the hydrolysis reaction is comparable to Ru-based bimetallic catalysts. A clearly mechanistic analysis of the hydrolytic reaction of AB based on experimental results and a density functional theory calculation is presented. [ABSTRACT FROM AUTHOR]

MicroRNAs (miRNAs) have been considered as important biomarkers for malignant tumors. In this study, we introduced an improved 99mTc labeling method for noninvasive visualization of overexpressed miRNAs in tumor-bearing mice. Anti-miRNA- 21 oligonucleotide (AMO) with partial 2′-O-methyl and phosphorothioate modification was designed and chemically synthesized. After conjugated with NHS-MAG3, AMO was labeled with 99mTc. Optimization was made to shorten reaction time and to improve labeling efficiency. Labeling efficiency was 97%, and specific activity was 2.78 MBq/ng. During 12 h, 99mTc-AMO showed no significant degradation by gel electrophoresis. Its radiochemical purity was stable, between 95.8% and 99.1%. Further, 99mTc-AMO decreased the level of miR-21 and increased the expression of PTEN protein at cellular level, shown by qRT-PCR and Western blot. Fluorescent protein labeled AMO displayed specific distribution and good stability in tumor cells. After the administration in tumor-bearing mice, 99mTc-AMO showed more radioactive uptake in the miR-21 overexpressed tumors than scramble control. Biodistribution results further proved the significant difference of tumor uptake between 99mTc-AMO and 99mTc-control. Therefore, this study presents an improved method with shorten time to prepare a 99mTc radiolabeled AMO. In addition, it supports the role of 99mTc-AMO for noninvasive visualization of miR-21 in malignant tumors. [ABSTRACT FROM AUTHOR]

In this paper, we report zircon U–Pb dating, Hf isotopes, geochemical and Sr–Nd isotopic data, with the aim the petrogenesis and regional tectonic evolution of Early Devonian bimodal volcanic rock in the South Altyn, NW China. New LA-ICPMS zircon U–Pb isotopic data constrained them at ca. 406 Ma. The mafic samples are characterized by high Fe, Cr and Ni contents, low Ti and Mg contents, slightly enriched LREE patterns, and low (La/Yb) N , La/Nb and La/Ta ratios, and positive ε Nd ( t ) values (+3.3 to +3.4), indicating that they were likely derived from strong batch-melting of the asthenosphere in the spinel facies field. The felsic rocks show an A-type affinity, with high alkalis, Fe, Ga, Zr, Nb, Ce and Y contents, low Mg, Sr content, high Rb/Sr and Ga/Al ratios, enrichment in LILE (e.g., Rb, K, Th, U and LREE) and depletion in Ba, Sr, Nb, Ta, P and Ti, and fractionated REE patterns with very strong negative Eu anomalies. These features, along with distinct ε Nd ( t ) values (−0.5 to +2.3) and mostly positive ε Hf ( t ) (−0.29 to +5.18), indicate that the felsic rocks were mainly generated by partial melting of the crust in low pressure and high temperature conditions, and simultaneously underwent slight magma mixing of such melts with mantle magma. According to the petrogenetic schemes and geological background of the Early Devonian bimodal volcanic rocks (tholeiite and A-type dacite–rhyolite), they should have formed in a post-collisional extensional setting. Moreover, on the basis of spatial and temporal distribution, and formation mechanism, the tectonic magmatic evolution of the early Paleozoic South Altyn Tagh could be divided into three stages: ① 505–472 Ma (continental collision), the magmatite formed under high-pressure conditions due to the deep subduction and initial tearing of continental slab; ② 467–450 Ma (continental slab break-off), the magmatite formed at high temperature and low pressure in virtue of felsic upper crust uplifting and mantle magma underplating; and ③ 432–385 Ma (post-collisional extension), the magmatite consists of A-type granites and bimodal volcanic rocks, which are the products of the interaction between mantle and crust, and asthenosphere upwelling. [ABSTRACT FROM AUTHOR]