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With the aim of enhancing the machining accuracy of the horizontal boring and milling machine tool, this study proposes an on-machine measurement methodology for identification and compensation of geometric errors of the facing head by using a touch-trigger probe and a precise sphere. Based on the past machining experiences provided by the machine supplier, the geometric errors of the facing head lead to the serious problem: the inner and outer holes of the workpieces are not concentric during the boring process. This problem causes the poor machining accuracy of the workpieces. As a result, in this study, a robust algorithm for calibrating the four geometric errors of the facing head is proposed by establishing the mathematical measurement equations. Furthermore, the mathematical measurement equations are mainly built by applying forward and inverse kinematic approach as well as the least square method. Finally, the measurement and machining verifications are also performed for demonstrating the feasibility and accuracy of the proposed measurement method. The experimental measurement results show that the position errors and the orientation errors are at most about − 76.3 μm and − 37.6 arcsec, respectively. On the other hand, after identifying the four geometric errors of the facing head, they are compensated to the controller. Consequently, the machining verification results show that the concentricity of inner and outer holes of the boring workpiece with compensation is significantly reduced to 0.024 mm from 0.179 mm. Conclusively, the efficiency and effectiveness of the proposed measurement method have been demonstrated. [ABSTRACT FROM AUTHOR]

[Display omitted] • System built with hollow fiber columns & perfusion culture technology. • Dynamic model established for ICSS system. • Regeneration processes extend cell lifetime. • DHA yield: 1237.8 g, up 485.0 %; Conversion rate: 97.7 %. Currently, the predominant method for the industrial production of 1,3-dihydroxyacetone (DHA) from glycerol involves fed-batch fermentation. However, previous research has revealed that in the biocatalytic synthesis of DHA from glycerol, when the DHA concentration exceeded 50 g·L−1, it significantly inhibited microbial growth and metabolism, posing a challenge in maintaining prolonged and efficient catalytic production of DHA. In this study, a new integrated continuous production and synchronous separation (ICSS) system was constructed using hollow fiber columns and perfusion culture technology. Additionally, a cell reactivation technique was implemented to extend the biocatalytic ability of cells. Compared with fed-batch fermentation, the ICSS system operated for 360 h, yielding a total DHA of 1237.8 ± 15.8 g. The glycerol conversion rate reached 97.7 %, with a productivity of 3.44 g·L−1·h−1, representing 485.0 % increase in DHA production. ICSS system exhibited strong operational characteristics and excellent performance, indicating significant potential for applications in industrial bioprocesses. [ABSTRACT FROM AUTHOR]

Lumbar spinal stenosis (LSS), which often occurs concurrently with degenerative spondylolisthesis (DS), is a common disease in the elderly population, affecting the quality of life of aged people significantly. Notwithstanding the frequently good effect of conservative therapy on LSS, a minority of the patients ultimately require surgery. Surgery for LSS aims to decompress the narrowed spinal canals with preservation of spinal stability. Traditional open surgery, either pure decompression or decompression with fusion, was considered effective for the treatment of LSS with or without DS. However, the long-term clinical outcomes of traditional open surgery are still unclear. Moreover, the disadvantages of conventional open surgery are extensive, examples including tissue injuries or secondary instability, with limited outcomes and significant reoperation rates. With the development and improvement of surgical tools, various minimally invasive spine surgery (MISS) methods, including indirect decompression techniques of interspinous process devices (IPDs) and direct decompression techniques such as microscopic spine surgery or endoscopic spine surgery (ESS), have been updated with enhancement. IPDs, such as Superion devices, were reported to behave with comparable physical function, disability, and symptoms outcomes to laminectomy decompression. As an emerging technique of MISS, ESS has beneficial hallmarks including minimal tissue injuries, reduced complication rates, and shortened recovery periods, thus gaining popularity in recent years. ESS can be classified in terms of endoscopic hallmarks and approaches. Predictably, with the continuous development and gradual maturity, MISS is expected to replace traditional open surgery widely in the surgical treatment of LSS associated with DS in the future. [ABSTRACT FROM AUTHOR]

Osteoporosis is a common disease characterized by reduced bone mineral density and impaired bone strength and is currently one of the leading causes of fracture and morbidity among the elderly worldwide. The pathological generation of osteoclasts is an important event in the development of extensive bone resorption. Thus, the development of a drug that targets osteoclasts may be beneficial in treating osteoporosis. Accordingly, in this study, we investigated the effects of senkyunolide H (SNH), an active component extracted from ligusticum chuanxiong Hort, on osteoporosis through a series of in vivo and in vitro experiments. First, we found that SNH had a therapeutic effect in ovariectomized mice by inhibiting osteoclast formation. Then, the inhibitory effect on osteoclast differentiation was confirmed in vitro. Further western blotting analysis revealed that SNH downregulated receptor activator of nuclear factor (NF)-κΒ ligand-induced NF-κB signaling activation, c-Jun N-terminal kinase (JNK) in the mitogen-activated protein kinase and extracellular signal-regulated kinase (ERK) signaling pathway. These data indicated that SNH may be a potential treatment for postmenopausal osteoporosis. • Osteoporosis is a common disease characterized by a reduction in bone volume. • Osteoclasts are the only cells responsible for bone resorption in humans. • We found therapeutic effects of senkyunolide H (SNH) on osteoporosis. • SNH inhibited osteoclast formation in vitro and vivo. • SNH acts by downregulating NF-κB, JNK and ERK signaling. [ABSTRACT FROM AUTHOR]

Action potential generation (spiking) in the neocortex is organized into repeating non-random patterns during both awake experiential states and non-engaged states ranging from inattention to sleep to anaesthesia-and even occur in slice preparations. Repeating patterns in a given population of neurons between states may imply a common means by which cortical networks can be engaged despite brain state changes, but super-imposed on this common firing is a variability that is both specific to ongoing inputs and can be re-shaped by experience. This similarity with specifically induced variance may allow for a range of processes including perception, memory consolidation and network homeostasis. Here, we review how patterned activity in neocortical populations has been studied and what it may imply for a cortex that must be both static and plastic. This article is part of the TheoMurphy meeting issue 'Memory reactivation: replaying events past, present and future'. [ABSTRACT FROM AUTHOR]

This paper studies the Pliable Index CODing problem (PICOD), which models content-type distribution networks. In the PICOD $({t})$ problem there are ${m}$ messages, ${n}$ users and each user has a distinct message side information set, as in the classical Index Coding problem (IC). Differently from IC, where each user has a pre-specified set of messages to decode, in the PICOD $({t})$ a user is “pliable” and is satisfied if it can decode any ${t}$ messages that are not in its side information set. The goal is to find a code with the shortest length that satisfies all the users. This flexibility in determining the desired message sets makes the PICOD $({t})$ behave quite differently compared to the IC, and its analysis even more challenging. This paper mainly focuses on the complete– ${S}$ PICOD $({t})$ with ${m}$ messages, where the set ${S}\subset [{m}]$ contains the sizes of the side information sets, and the number of users is ${n}=\sum _{s\in {S}}\binom {m} {s}$ , with no two users having the same side information set. Capacity results are shown for: (i) the consecutive complete– ${S}$ PICOD $({t})$ , where ${S}=[{s}_{\text {min}}:{s}_{\text {max}}]$ for some $0 \leqslant {s}_{\text {min}}\leqslant {s}_{\text {max}} \leqslant {m}-{t}$ , and (ii) the complement-consecutive complete– ${S}$ PICOD $({t})$ , where ${S}=[0: {m}-{t}]\backslash [{s}_{\text {min}}:{s}_{\text {max}}]$ , for some $0 < {s}_{\text {min}}\leqslant {s}_{\text {max}} < {m}-{t}$. The novel converse proof is inspired by combinatorial design techniques and the key insight is to consider all messages that a user can eventually decode successfully, even those in excess of the ${t}$ required ones. This allows one to circumvent the need to consider all possible desired message set assignments at the users in order to find the one that leads to the shortest code length. The core of the novel proof is to solve the critical complete– ${S}$ PICOD $({t})$ with ${m} = 2{s}+{t}$ messages and ${S}=\{{s}\}$ , by showing the existence of a user who can decode ${s}+{t}$ messages regardless of the desired message set assignment. All other tight converse results for the complete– ${S}$ PICOD $({t})$ can be deduced from this critical case. The converse results show the information theoretic optimality of simple linear coding schemes. By similar reasoning, all complete– ${S}$ PICOD $({t})$ where the number of messages is ${m}\leqslant 5$ can be fully characterized. In addition, tight converse results are also shown for the PICOD(1) with circular-arc network topology hypergraph. [ABSTRACT FROM AUTHOR]

The direct amination of cyanohydrins with amines via a catalytic cyano-borrowing reaction was developed. The transformation features broad substrate scope, excellent functional group compatibility, and very mild and simple operations. Moreover, a titanium catalyst supported by quinine and (S)-BINOL ligands enabled an asymmetric cyano-borrowing reaction with moderate to high enantioselectivity. [ABSTRACT FROM AUTHOR]

Evaluating the performances of a set of entities called decision making units (DMUs) which convert multiple inputs into multiple outputs has long been considered as a difficult task because one is dealing with complex economics. This work proposes an inequality approach to evaluate the performances of DMUs. Inequalities consist of expressions of the production possibility set and the line segments joining the evaluated DMU to the positive output-axes. However, in real-world application involving performance measurement, inputs and outputs are often imprecise and fluctuated. In this case, a fuzzy inequality approach is proposed to evaluate the performances. What is more, fuzzy relative efficiency is dependent upon the number of solutions. Furthermore, the minimal element is used to distinguish the fuzzy relative efficient DMUs. Finally, two numerical examples are used to illustrate the fuzzy approach and compare the results with those obtained with alternative fuzzy approaches. [ABSTRACT FROM AUTHOR]

Objective: To assess the treatment of osteosarcomas of the femoral diaphysis through wide en bloc excision and reconstruction of the defect by pasteurized autograft combined with vascularized fibular transfer. Methods: A single‐center, retrospective study was performed of 15 selected patients (six females, nine males) whose lesion in the middle diaphysis of the femur were treated by en bloc excision and reconstruction of the bone defect with recycled pasteurized autograft combined with vascularized fibular graft between January 2000 and December 2011. The primary diagnoses of the patients were osteosarcoma (15 patients), and one of these patients had a pathological fracture. The mean patient age at the time of surgery was 22.3 years (range, 10–40 years). All these cases of bone tumors were staged according to Ennekingʼs criteria with three stage IIA cases, and 12 stage IIB cases. The patients were examined clinically and radiologically every month during the first 6 months after surgery to exclude the evidence of infection and local recurrence, then at 3‐monthly intervals for 2 years and then at 6‐monthly intervals for life. Function was assessed using the Musculoskeletal Tumor Society Scoring system (MSTS). Results: At a mean follow‐up of 65.1 months (range, 31–131 months), all the patients had achieved bony union at the final follow‐up. The mean time to bone union of the proximal junctions of vascularized fibula was 8.7 months (range, 6.0–13.0 months) and that of the distal junctions was 9.2 months (range, 6.0–12.0 months). Mean union time of the proximal junctions of the pasteurized autogenous bone was 14.3 months (range, 10.0–25.0 months) and that of the distal junctions was 15.6 months (range, 10.0–27.0 months). There were two fractures of the pasteurized bone during the operation. One patient, in whom the plate had been removed after union at 3 years postoperatively, sustained a fracture in a fall. This was treated with external fixation and united uneventfully. One patient, in whom two of the proximal screws had been broken, developed coxa vara. There was no infection. There were three pulmonary metastases and no local recurrence. The mean function score was 81.8%. Five patients died of their underlying disease, and the disease‐specific survival of patients was 69.1%. Conclusions: Pasteurized autogenous bone graft combined with a vascularized fibula graft is a useful reconstruction method for large bone defects after resection of osteosarcoma in the femur. [ABSTRACT FROM AUTHOR]

The slipstreams induced by high-speed trains under crosswind are studied in this paper by the detached-eddy simulation (DES) method. First, the formation and development of the slipstream induced by a train (5 cars) with a 4 m nose length are analysed in detail, including at different heights and widths on the windward side (WWS) and leeward side (LWS). Then, the slipstreams with and without crosswind are compared, and the differences are presented. Finally, by considering four different nose lengths (4, 7, 9, and 12 m) under crosswind, the differences in the slipstreams induced by different nose lengths are given and analysed. The results show that on the WWS at z = 0.5 m above the top of the rail (TOR), the slipstream velocity coefficient ' U ' decreases at the position of the nose due to a velocity cancellation and stagnation effect. On the LWS, from D = 0 m–145 m, where 'D' represents the distance from the nose point, at y = 1.9 m and 2.15 m beside the centre of rail (COR), there are two peak values at the position of the nose caused by the impact of the nose point and the strong disturbance of the bogie area. At y = 2.65 m and 3.65 m, the change in U is relatively complex due to the effect of vortexes on the LWS. The effect of crosswind on the slipstream velocity is different in different regions around the train. In the region close to the train side and the bottom, the value of U on the WWS is the smallest, followed by that in the no wind case, and that on the LWS is the largest. In other regions, the values of U on the WWS and LWS are larger than that in the no wind case. For different nose lengths, on the WWS, the change in U is smoother with increasing nose length due to more stable flow around the nose. On the LWS, the change in U with increasing nose length is relatively clear only at the positions around the nose of the head car and tail car. In the regions along the middle cars, the U values for trains with different nose lengths change with the same trends and vary intertwined. • The formation and development of the slipstream velocity induced by a high-speed train under crosswind are investigated. • The effects of nose length on the slipstream are concluded by considering four different nose lengths—4, 7, 9, and 12 ​m. • On the LWS, the change of slipstream with increasing nose length is relatively clear only at the position around the nose. [ABSTRACT FROM AUTHOR]

Highlights • Impact of marshalling length and form on the pressure propagation was studied by Mach diagrams. • Effects of the coupling structure on the surface pressure of the train body and the tunnel wall. • The influence of marshalling parameters on the maximum pressure peak of tunnel wall and train body. • The pressure changes at the coupling structure was analysed. Abstract Unsteady Reynolds-averaged Navier-Stokes (URANS) simulations were performed to simulate trains with different marshalling forms and lengths entering a tunnel. Three models, including a short train, a double train and a long train, were used to analyse the influence of the train configuration on the pressure variations during a train's passage. The results of the numerical predictions were validated against existing experimental data, with which they showed good agreement. The differences in the maximum pressure peak distribution and the pressure fluctuations were analysed by means of Mach diagrams. The results show that the grouping length exerts a considerable influence on the amplitude of the pressure on the train body and that the influence of the grouping length on the pressure variation on the tunnel wall varies with the location in the tunnel. The tunnel space can be divided into three and four zones with regard to the influences on the maximum positive and negative pressure values, respectively. The different marshalling forms also influence the maximum peak values and local profiles of the pressure history curves, although this influence is much slighter than that of the train's grouping length. [ABSTRACT FROM AUTHOR]

Background/Aims: Metastasis is the major cause of death in patients with osteosarcoma. There is an urgent need to identify molecular markers that promote metastasis. Cluster of differentiation 44 is a receptor for hyaluronic acid (HA) and HA-binding has been proven to participate in various biological tumor activities, including tumor progression and metastasis. Methods: We performed a meta-analysis to investigate the relationship between CD44 expression, survival, and metastasis in patients with osteosarcoma. We then utilized the CRISPR-Cas9 system to specifically silence CD44 in highly metastatic human osteosarcoma cells (MNNG/HOS and 143B) and further determined the functional effects of CD44 knockout in these cells. Results: The meta-analysis demonstrated that a high level of CD44 may predict poor survival and higher potential of metastasis in patients with osteosarcoma. The expression of CD44 in highly metastatic human osteosarcoma cell lines was efficiently blocked by CRISPR-Cas9. When CD44 was silenced, the proliferation and spheroid formation of these osteosarcoma cells was inhibited under 3-D culture conditions. Furthermore, the migratory and invasive functions were also impaired in these highly metastatic osteosarcoma cells. Conclusion: These results suggest that developing new strategies to target CD44 in osteosarcoma may prevent metastasis and improve the clinical outcome of osteosarcoma patients. [ABSTRACT FROM AUTHOR]

The use of double-unit trains is becoming a common means of increasing passenger capacity for a rail network. However, their expanded usage may create additional aerodynamic challenges. The present work obtains the characteristics of the slipstream caused by single and double unit trains using the detached eddy simulation (DES) method for 1/20th scaled models. The numerical results are verified by full-scale experiments. The slipstream velocities and pressures obtained by the two train models at different distances from the center of track (COT) and the top of rail (TOR) are compared. The coupling structure of the double-unit train model is found to produce a velocity peak that is much greater than that of the single-unit train model in the same position. At the area away from the COT and close to the TOR, the velocity of the far wake region is larger for the double-unit train model. The coupling structure also leads to a positive pressure change in the coupling region, and its value is comparable to or even much greater than that caused by the nose. It is considerable that the subsequent pressure criteria could take the positive pressure on the coupling region into account for the double-unit train. [ABSTRACT FROM AUTHOR]

In this paper, solution-processed Au-coated Ag nanowires (Ag@Au NWs) was successfully fabricated as top electrode by spray deposition in planar perovskite solar cells (PVSCs) with structure ITO/PTAA:F4-TCNQ/MAPbI 3 /PC 61 BM/Ag@Au NWs, which shows favorable bandgap alignment. Sheet resistance of electrode and series resistance of solar cells over time as well as the stability of PVSCs were measured. The results indicate that the Au shell which serves as a physical separation layer sandwiched in between the perovskite/hole transporting layer (HTL) and the halide-reactive silver nanowires (Ag NWs) can significantly enhance the stability of PVSCs. The efficiency of solar cells employing Ag NWs as top electrode decreases rapidly within 10 min while the efficiency of solar cells employing Ag@Au NWs still remains 85% of its original efficiency even after one week in air. The as-fabricated PVSCs exhibit a power conversion efficiency of 11.0% with an open-circuit voltage of 0.99 V, a short-circuit current density of 18.5 mA/cm 2 , and a fill factor of 64.3%. This work paves a way for realizing low cost, stable, all solution processable PVSCs. [ABSTRACT FROM AUTHOR]

As a high-speed train passes through a tunnel, the intense aerodynamic pressure wave outside the train penetrates into the passenger compartments, changing the pressure environment inside the train and causing discomfort to passengers. This phenomenon varies enormously among tunnels of different lengths. To evaluate the real influence of tunnel length on the interior pressure environment of the carriages and ensure passenger comfort, field measurements were conducted on a CRH2A train operating on the Hefei-Wuhan rail line in China; twelve tunnels with lengths ranging from 72 to 10766 m were investigated. Pressure sensors were deployed along the outside and inside train surfaces to investigate the variations in interior pressure with the exterior pressure environment. The results show that the interior pressure curve over time in a short tunnel has a single-trough form, very different from that in a long tunnel. The total variation of interior pressure increases monotonically with tunnel length from 72 to 10766 m, whereas the maximum pressure variation within a 3 s period occurs in the 1080 m tunnel; the variation within a 1 s period is not significantly affected by the tunnel length for tunnel lengths greater than 556 m. There is a delay in the 1 s interior pressure variation in response to an exterior pressure change; this delay is independent of the tunnel length and is approximately 1.2 s in this test. It is found that the reason for passengers’ ear discomfort in very long tunnels, which is mainly an effect of excessive changes in pressure over a long period of time, could be different from that in long or short tunnels. [ABSTRACT FROM AUTHOR]

Using the three criterions of the concurrence, the negative eigenvalue and the geometric quantum discord, we investigate the quantum entanglement and quantum correlation dynamics of two two-level atoms interacting with the coherent state optical field. We discuss the influence of different photon number of the mean square fluctuations on the temporal evolution of the concurrence, the negative eigenvalue and the geometric quantum discord between two atoms when the two atoms are initially in specific three states. The results show that different photon number of the mean square fluctuations can lead to different effects of quantum entanglement and quantum correlation dynamics. [ABSTRACT FROM AUTHOR]

This paper studies inner and outer bounds on the degrees of freedom (DoF) region of the multi-antenna two-user Gaussian interference channel with an instantaneous relay (IR) or relay without delay. It is assumed that the two transmitters and the two receivers have \mathop \mathrm \mathsf M\nolimits antennas, while the IR receives through \mathop \mathrm \mathsf Nr\nolimits antennas and transmits through \mathop \mathrm \mathsf Nt\nolimits antennas. In the proposed achievable scheme, which generalizes a known one for the case \mathop \mathrm \mathsf M\nolimits = \mathop \mathrm \mathsf Nr\nolimits = \mathop {\mathrm {\mathsf {Nt}}}\nolimits to any (\mathop \mathrm \mathsf M\nolimits, \mathop \mathrm \mathsf Nr\nolimits, \mathop {\mathrm {\mathsf {Nt}}}\nolimits) , the IR performs memoryless linear operations on its received signal so as to neutralize interference at the receivers, and the beamforming matrices used by the IR and the transmitters are jointly designed. This joint design strictly outperforms known achievable schemes. Two outer bounds are derived. An information theoretic outer bound is obtained by giving the receivers or the IR genie side information, so that the DoF region of the resulting enhanced channel is known; this converse is valid for any type of processing at the IR and shows the optimality of the proposed achievable scheme for some (\mathop \mathrm \mathsf M\nolimits, \mathop \mathrm \mathsf Nr\nolimits, \mathop {\mathrm {\mathsf {Nt}}}\nolimits) . A linear processing outer bound is obtained when the IR is restricted to performs linear operations, without any memoryless restriction, on its received signal and shows the optimality of the proposed achievable scheme among all linear processing schemes at the IR. As a result of independent interest, the DoF region of the classical multi-antenna two-user Gaussian interference channel without relay when the channel matrices can have any structure is also derived, which generalized available DoF region results that were derived under certain assumptions on the structure of the channel matrices. [ABSTRACT FROM PUBLISHER]

An efficient copper(I)-catalyzed one-pot domino reaction for the ( Z)-selective construction of diazabicyclo[5.3.0]decatriene derivatives under mild conditions has been developed. This protocol was initiated by a Cu(I)-catalyzed azide-alkyne cycloaddition (CuAAC), followed by a ring opening rearrangement and then subsequent higher-order [8+2] cycloaddition of azaheptafulvene with ketenimine intermediates at the corresponding C-2 and N-3 sites, affording biologically active heterocycles in good to high yields. [ABSTRACT FROM AUTHOR]

The three-dimensional compressible Navier-Stokes equation and k-ε turbulence model are used to simulate the flow and pressure waves caused by two trains passing each other in a tunnel. The simulation results were verified by comparison with the results of a full-scale experiment. This simulation results indicate that the positive peak of the initial compression wave on the tunnel wall has a logarithmically decreasing trend with increasing nose length. This tendency is more obvious near the tunnel portal than in the tunnel, and the positive peak caused by a train with a nose length of 12 m at a distance of 20 m from the tunnel entrance is 10.26% less than that caused by a train with a nose length of 4 m. Throughout the intersection process, the peak-to-peak amplitude of body surface pressure decreases with increasing longitudinal distance from the front nose tip. The influence of different nose lengths on the surface pressure on the train body is mainly concentrated at the front and rear of the train. The fluctuation amplitude of the surface pressure on the head car with a 4 m nose is 1.63 times that of a head car with a 12 m nose. The amplitudes of the lateral force and overturning moment are also influenced by the nose length, with the strongest effect on the head car and a stronger effect on the middle car than on the tail car. A shorter train nose results in a more significant influence on the train total drag. As the nose length changes from 4 m to 7 m, the maximum total drag decreases by 6.71%; however, as the nose length changes from 9 m to 12 m, the maximum total drag decreases by only 0.16%. [ABSTRACT FROM AUTHOR]

Using compressible, unsteady and sliding meshing technologies, the aerodynamic loads including transient pressure, lateral force, and overturning moment that are caused by a single train moving through a double-track tunnel or two trains passing each other in a tunnel were calculated. The dynamic response generated by applying these loads to a train body was also analysed. The results show a large difference in the pressure on both sides of the vehicle nose when a single train moves through a double-track tunnel and when two trains pass each other in a tunnel. The pressures at the symmetric measuring points on both sides of the middle of the train body are approximately the same except at the moment of passing. When the train passes the measuring points, the pressure change at the symmetric measuring points on the tunnel wall closer to the train is obviously larger than that farther from the train; the pressure changes are approximately the same at all other times. Therefore, the propagation of the pressure wave in the tunnel has good one-dimensional characteristics. Under dynamic loads in the tunnel, especially those generated by two trains passing each other in the tunnel, the lateral and vertical displacements of the underframe and side walls all increase significantly. The lateral acceleration on the roof is significantly greater than that of the underframe, which has a rolling movement below the centre of gravity. For the measuring points on both the side wall and underframe, the vertical accelerations at both ends are larger than that in the middle of the body because of a pitching motion. The horizontal and vertical vibration acceleration for a train passing another train in a tunnel are 33.8% and 47.2% larger than those for a train operating in open air, respectively. [ABSTRACT FROM AUTHOR]

Quantum correlations of two atoms in a system of two entangled atoms interacting with the binomial optical field are investigated. In eight different initial states of the two atoms, the influence of the strength of the dipole-dipole interaction, probabilities of a the Bernoulli trial and particle number of the binomial optical field on the temporal evolution of the geometrical quantum discord between two atoms are discussed. The result shows that two atoms always exist the correlation for different parameters. In addition, when and only when the two atoms are initially in the maximally entangled state, the temporal evolution of geometrical quantum discord is not affected by the parameters, and always keep in the degree of geometrical quantum discord that is a fixed value. [ABSTRACT FROM AUTHOR]

Two fluorene derivatives, 2-(1,1′:3′,1″-triphenyl-5′-yl)-9,9-diphenyl-9H-fluorene (TPF) and (9,9-diphenyl-9H-fluoren-2-yl)diphenylphosphine oxide (DFPPO) with wide bandgap and good thermal stability were synthesized. The electron mobility of DFPPO is 5 times higher than that of TPF because of the introduction of the electron-withdrawing diphenylphosphine oxide group. The planar heterojunction organic ultraviolet photodetectors (UVDs) were fabricated by applying TPF or DFPPO as electron acceptor, 2,7-dioctyl[1]benzothieno[3,2-b][1]benzothiophene (C8-BTBT) as donor. The UVDs with structure of ITO/PEDOT:PSS/C8-BTBT/DFPPO/LiF/Al presented higher ultraviolet response compared to the TPF based counterpart. Corresponding dark to light current ratio and higher sensitivity is about 179 and 0.69 mA/W under illumination of 1 mW/cm 2 365 nm UV light and bias of −0.5 V. [ABSTRACT FROM AUTHOR]

As an important urban infrastructure, rail transit not only has transportation function, but also has a close connection and harmonious development with the surrounding urban space. Taking Beijing Metro Line 5 as an example, each station of Beijing Metro Line 5 was analyzed by GIS software and Echarts chart based on POI data. The functions of subway site type were divided into main function, secondary function and no signifi cant function, and various types of sites within the main functional characteristics of urban functions were discussed in details. The paper presents a new method for identifying urban functional features, which can be applied to not only other metro stations in Beijing but also the same type of cities. Moreover, it lays a foundation for the research of rail transit subway stations and their related researches. [ABSTRACT FROM AUTHOR]

Microbial communities of activated sludge (AS) play a key role in the performance of wastewater treatment processes. However, seasonal variability of microbial population in varying AS-based processes has been poorly correlated with operation of full-scale wastewater treatment systems (WWTSs). In this paper, significant seasonal variability of AS microbial communities in eight WWTSs located in the city of Guangzhou were revealed in terms of 16S rRNA-based Miseq sequencing. Furthermore, variation redundancy analysis (RDA) demonstrated that the microbial community compositions closely correlated with WWTS operation parameters such as temperature, BOD, NH4+-N and TN. Consequently, support vector regression models which reasonably predicted effluent BOD, SS and TN in WWTSs were established based on microbial community compositions. This work provided an alternative tool for rapid assessment on performance of full-scale wastewater treatment plants. [ABSTRACT FROM AUTHOR]

Sarcomas include some of the most aggressive tumors and typically respond poorly to chemotherapy. In recent years, specific gene fusion/mutations and gene over-expression/activation have been shown to drive sarcoma pathogenesis and development. These emerging genomic alterations may provide targets for novel therapeutic strategies and have the potential to transform sarcoma patient care. The RNA-guided nuclease CRISPR-Cas9 (Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)-associated protein-9 nuclease) is a convenient and versatile platform for site-specific genome editing and epigenome targeted modulation. Given that sarcoma is believed to develop as a result of genetic alterations in mesenchymal progenitor/stem cells, CRISPR-Cas9 genome editing technologies hold extensive application potentials in sarcoma models and therapies. We review the development and mechanisms of the CRISPR-Cas9 system in genome editing and introduce its application in sarcoma research and potential therapy in clinic. Additionally, we propose future directions and discuss the challenges faced with these applications, providing concise and enlightening information for readers interested in this area. [ABSTRACT FROM AUTHOR]

A simple and novel electrochemical sensor was developed to determine levofloxacin based on the Ag nanoparticles/electrospun CeO2-Au composite nanofibers modified glassy carbon electrode (AgNPs/CeO2-Au/GCE). The electrospun CeO2-Au composite nanofibers provided a stable matrix and a large surface area for the fabrication of the sensing interface while the Ag nanoparticles dramatically promoted the current of levofloxacin on the electrode. Scanning electron microscopy and electrochemical methods were used to characterize the AgNPs/CeO2-Au composite film. The oxidative peak current was linear with the levofloxacin concentration in the range of 0.03-10 μM. The detection limit was as low as 0.01 μM (S/N = 3), and the sensitivity could reach 1240 μA mM-1 cm-2. Furthermore, the proposed modified electrode also could be feasibly applied to the determination of levofloxacin in human urine and blood serum samples. [ABSTRACT FROM AUTHOR]

Highlyregioselective andenantioselective asymmetric hydrogenation of cyclic dienamides catalyzedby an Rh-DuanPhos complex has been developed, which provides a readilyaccessible method for the synthesis of chiral cyclic allylic aminesin excellent enantioselectivities (up to 99% ee). The products arevaluable chiral building blocks and could be easily transformed tomultisubstituted cyclohexane derivatives. [ABSTRACT FROM AUTHOR]

The pressure integral method is frequently used to obtain the train aerodynamic forces in experiments, but the effect of the pressure pipe length on the pressure amplitude is not understood. In this paper, based on field tests without pressure pipes, the dominant frequency (DF) ranges of the pressure pulsations on the train surface under various conditions, including open-air, crosswind, and tunnel conditions, were analyzed. Then the effect of the pressure pipe length on the pressure amplitude with various pulsation frequencies was investigated. Finally, in a full-scale test under crosswinds, the selected pressure pipe length was applied to verify its reliability and to study the train aerodynamic performance. The results showed that the maximum DF occurred when two trains passed each other (near 60 Hz), and the DF under crosswinds was the smallest (less than 1 Hz). When the pressure pulsation frequency was less than 1 Hz, the error range of the pressure amplitude was less than 5% with a pressure pipe length of ≤8 m. The pressure pipe is a polyvinyl chloride (PVC) pipe with an outer diameter of 2 mm and an inner diameter of 1.8 mm. The full-scale test results for the windproof ability of different windbreak walls and the aerodynamic forces of the train showed that the current pressure pipe length was reasonable and could reflect the actual operating conditions of the train under crosswinds. • The pressure pulsation frequencies on the train surface in diverse conditions were obtained. • A reasonable length of plastic pressure pipe was proposed. • The full-scale test of the single- and double-unit train under crosswinds was conducted using the proposed pressure pipe. [ABSTRACT FROM AUTHOR]

Bone and soft tissue sarcomas with complex and varied clinical, imaging, and pathological characteristics cannot be diagnosed and treated by a single discipline, as each discipline has some limitations. This study aimed to explore the role of a multidisciplinary team (MDT) in the diagnosis and treatment of bone and soft tissue sarcomas over the past four consecutive years. The subjects were 269 patients discussed during MDT meetings at a Bone and Soft Tissue Sarcomas Center in South China. The diagnosis, relapse diagnosis, unplanned resection, management of pulmonary nodules, and treatment of refractory and advanced tumors were compared to similar data provided in the literature to (i) determine whether the MDT significantly affected the diagnosis and treatment of bone and soft tissue sarcomas, and (ii) explore trends in the types of patients with bone and soft tissue sarcomas and treatment decision-making since the establishment of the MDT. Results revealed that the MDT significantly improved preoperative diagnostic accuracy for patients with bone and soft tissue sarcomas; the accuracy of diagnosis and relapse diagnosis by the MDT reached 95.42% and 100%, respectively. After an MDT discussion, the positive pathology rate for extended resection after unplanned resection was 81.2%. The overall accuracy of the MDT in determining the nature of pulmonary nodules was 87.1–91.9%. For patients presenting with pulmonary nodules in osteosarcoma, no statistically significant difference in survival was shown between cases discussed by the MDT and those without an MDT discussion (p = 0.5751). Collectively, the MDT can play a positive role in accurate preoperative diagnosis, relapse diagnosis, the decision to extend resection after an unplanned resection, and the diagnostic accuracy of pulmonary nodules. [ABSTRACT FROM AUTHOR]

Abstract: The crystal phase, particle size, and morphology of organic pigments play an important role on the surface coating properties, such as substrate absorbency, surface smoothness, the light scattering properties, gloss, roughness, coating power, rheology and stability upon storage, etc. This paper aims to study the effect of photo acid generator (PAG) containing the stibium ion on the crystal structure and morphology of the regenerated pigment from the precursor of indanthrone in organic solvent. As measured from ultraviolet–visible spectroscopy and Fourier transform infrared spectroscopy, it was discovered that adding PAG accelerated the conversion of latent pigment to regenerated pigment. In addition, field emission scanning electron microscopy, energy dispersive spectroscopy and X-ray diffraction analysis indicated that, as the amount of PAG increased, the regenerated pigment lost its crystal structure, which particle size is increased from 1 to 4 μm and morphology is changed from a bar like form to a cubic and spherical form. [Copyright &y& Elsevier]

Der direkte Weg: Ausgehend von leicht zugänglichen Ausgangsstoffen gelang die effiziente Synthese chiraler allylischer Amine und aliphatischer Amine mithilfe einer Rhodium ‐ katalysierten asymmetrischen Hydrierung. Ein chirales Z ‐ allylisches Amin wurde zum ersten Mal in einer von Rhodium/DuanPhos katalysierten asymmetrischen Hydrierung erhalten. TMS=Trimethylsilyl, cod=Cyclooctadien, TON=Umsatzzahl. [ABSTRACT FROM AUTHOR]

The direct route: A Rhodium‐catalyzed asymmetric hydrogenation method for the efficient synthesis of a broad range of chiral allylic amines and aliphatic amines from readily available materials was developed. A chiral Z‐allylic amine was obtained for the first time through a Rhodium–DuanPhos‐catalyzed asymmetric hydrogenation. TMS=Trimethylsilyl, cod=cyclooctadiene, TON=turnover number. [ABSTRACT FROM AUTHOR]

Objectives: To summarize our experience and mid-term results of reconstruction with Iliotibial tract grafts for multiple ligament injuries. Methods: Between July 1997 and December 2003, multiple ligament injuries of 15 patients were reconstructed with Iliotibial tract grafts in arthroscopy. There were 5 women and 10 men. The mean age at the time of the surgery was 30.5 years (range 25-43 years). There were 7 cases who were injured with combined ACL rupture and the PCL, and 8 cases were with disruption of both the ACL and the PCL, combined with damage of the medial collateral ligament. Results: Fifteen patients were followed up for a mean of 7.5 years (range 6-12 years). The overall mean postoperative Lysholm score was 84.3 ± 5.7. At final IKDC qualification, 60.0 % of the knees were normal or nearly normal. The overall average Tegner activity score decreased significantly at the re-examination compared to the activity score before accident (3.6 ± 0.5 vs. 5.1 ± 0.6). Conclusions: Reconstruction with Iliotibial tract grafts in arthroscopy was a reliable treatment for multiple ligament injuries. [ABSTRACT FROM AUTHOR]

A novel method to desymmetrize meso-anhydrides into lactones via asymmetric hydrogenation catalyzed by the Ir–C3*-TunePhos complex has been developed. Various chiral lactones were synthesized with full conversion and excellent enantioselectivity under high reaction temperature. [ABSTRACT FROM AUTHOR]

Background: Persistence of hip dysplasia into adolescence and adulthood can lead to an abnormal gait, which would do harm to patients' physiological and psychological health. The aim of this study was to summarize our results of tibial lengthening for reconstruction of limb length discrepancy in Crowe Type IV developmental dysplasia of hip in adulthood. Methods: Between January 2000 and December 2002, 11 patients' limb length discrepancy in Crowe Type IV developmental dysplasia of hip was treated by tibial lengthening. There were 8 women and 3 men, aged from 18 to 25 years, averaged 21.2 years. The limb length discrepancy was 4.0-7.1 cm. Results: Eleven patients were followed up for a mean of 110 months. The limping was much improved from a moderate or severe degree to a mild degree in all patients. In the group of callus distraction with external fixation, the average external fixation index was 37.0 days/cm. In the group of callus distraction over an intramedullary nail, the average external fixation index was 16.6 days/cm, and the mean radiographic consolidation index was 34.4 days/cm. The extent of lengthening ranged from 4.0 to 7.0 cm. Conclusions: Tibial lengthening may be a reliable treatment for untreated unilateral developmental dysplasia of hip in adolescents without pain but eager for improving limping. [ABSTRACT FROM AUTHOR]

In designing wireless sensor networks, it is important to reduce energy dissipation and prolong network lifetime. This paper presents research on the existing clustering algorithm applied in heterogeneous sensor networks and then puts forward an energy-efficient prediction clustering algorithm, which is adaptive to sensor networks with energy and objects heterogeneous. This algorithm enables the nodes to select the cluster head according to factors such as energy and communication cost, thus the nodes with higher residual energy have higher probability to become a cluster head than those with lower residual energy, so that the network energy can be dissipated uniformly. In order to reduce energy consumption when broadcasting in clustering phase and prolong network lifetime, an energy consumption prediction model is established for regular data acquisition nodes. Simulation results show that compared with current clustering algorithms, this algorithm can achieve longer sensor network lifetime, higher energy efficiency, and superior network monitoring quality. [ABSTRACT FROM AUTHOR]

The purpose of this study was to report a case with osteomyelitis of the proximal tibia as an infant leading to an atrophic nonunion with a segmental bone defect and limb shortening. The patient was treated by callus distraction with external fixator three times, and regeneration of the proximal tibia epiphysis appeared during the management. The activation of the resting mesenchymal stem cells might contribute to the regeneration of the epiphysis and osteogenesis in the sites of atrophic nonunion. [ABSTRACT FROM AUTHOR]

An efficient combination method of Laplace transform and mixed multiscale finite-element method for coupling partial differential equations of flow in a dual-permeability system is present. First, the time terms of parabolic equation with unknown pressure term are removed by the Laplace transform. Then the transformed equations are solved by mixed FEMs which can provide the numerical approximation formulas for pressure and velocity at the same time. With some assumptions, the multiscale basis functions are constructed by utilizing the effects of finescale heterogeneities through basis functions formulation computed from local flow problems. Without time step in discrete process, the present method is efficient when solving spatial discrete problems. At last, the associated pressure transform is inverted by the method of numerical inversion of the Laplace transform. [ABSTRACT FROM AUTHOR]

Abstract: An obvious pressure change and a micro-pressure wave are generated when a train enters a tunnel at high-speed, which impacts on the comfort of passengers and the environment around the tunnel. Thus, it is necessary to study the aerodynamics of tunnels in order to reduce the pressure change and micro-pressure wave. Our laboratory owns an advanced moving-model device that can simulate two trains crossing in the open air or trains entering a tunnel, with a maximum speed of 400km/h. This paper studies the pressure change, the micro-pressure wave and a series of hoods using three-dimensional numerical simulations and moving-model experiments. From a comparative study, we obtain rules governing the influence of hoods on the micro-pressure wave, and reasonable shapes and parameters of hoods are designed. [Copyright &y& Elsevier]

In this paper we are concerned with finite element approximations to the evaluation of American options. First, following W. Allegretto etc., SIAM J. Numer. Anal. 39 (2001), 834–857, we introduce a novel practical approach to the discussed problem, which involves the exact reformulation of the original problem and the implementation of the numerical solution over a very small region so that this algorithm is very rapid and highly accurate. Secondly by means of a superapproximation and interpolation postprocessing analysis technique, we present sharp L2-, L∞-norm error estimates and an H1-norm superconvergence estimate for this finite element method. As a by-product, the global superconvergence result can be used to generate an efficient a posteriori error estimator. [ABSTRACT FROM AUTHOR]

Based on the quantum information theory, this paper has investigated the entanglement properties of a system which is composed of the two entangled two-level atoms interacting with the two-mode entangled coherent fields. The influences of the strength of light field and the two parameters of entanglement between the two-mode fields on the field entropy and on the negative eigenvalues of partial transposition of density matrix are discussed by using numerical calculations. The result shows that the entanglement properties in a system of a pairwise entangled states can be controlled by appropriately choosing the two parameters of entanglement between the two-mode entangled coherent fields and the strength of two light fields respectively. [ABSTRACT FROM AUTHOR]

Summary: Objective: Delivering alternating currency (AC) to right ventricular endocardium to induce ventricular fibrillation (VF) in mice is complicated. We tried to validate whether transoesophageal AC stimulation could induce VF and how long AC stimulation had to be sustained to prevent the spontaneous cardioversion of VF in mice. Methods: A pacing electrode was inserted orally into the oesophagus and AC was delivered to esophagus through the pacing electrode to stimulate the heart and induce VF in 15 mice. The incidence of VF and time of AC stimulation were recorded 4min after onset of VF cardiopulmonary resuscitation (CPR) was started. Results: VF was induced by short AC stimulation in all 15 mice. With the prolongation of AC stimulation, the incidences of spontaneous cardioversion of VF decreased whereas the incidence of pulseless electrical activity (PEA) increased accordingly. Following the termination of prolonged AC stimulation, VF occurred only in 1 of 15 mice, but PEA in 14 of 15 mice. Before CPR 1 of 15 and 12 of 15 animals remained in VF and in PEA, respectively, while 2 of 15 animals developed into asystole. After CPR, 11 of 15 animals were successfully resuscitated. Conclusion: VF can be induced by a short period of transoesophageal AC stimulation in mice. However, prolonged AC stimulation is prone to induce PEA other than VF. Nonetheless, the development of a mouse CA model in this manner is simpler and easier, which may have practical significance for facilitating experimental investigation on CA and CPR. [Copyright &y& Elsevier]

Summary: Objective: To investigate whether transoesophageal cardiac pacing can induce ventricular fibrillation (VF) and how long the cardiac pacing has to be sustained to prevent the reversion of the VF induced. Methods: A pacing electrode was inserted orally into the oesophagus and high-frequency ventricular pacing was performed so as to elicit VF in 25 Sprague–Dawley rats. Incidences of VF and time of cardiac pacing were observed and recorded. Four minutes after onset of VF cardiopulmonary resuscitation (CPR) was initiated. Results: A short interval of high-frequency ventricular pacing caused an immediate drop of blood pressure, loss of pulse and increase of right atrial pressure in the same time frame. When the cardiac pacing was terminated, VF was elicited at least once or more than once in all of the 25 rats. However, the VF elicited by the burst stimulation could be defibrillated spontaneously. With the prolongation (120–180s) of cardiac pacing, the incidence of defibrillation of VF decreased from 100 to 0%. VF persisted in 19 of 25 animals, developed into asystole in 5 of 25 animals and converted into pulseless electrical activity in 1 of 25 animals prior to CPR. Following CPR 22 of 25 animals were resuscitated. Conclusions: Transoesophageal cardiac pacing can induce VF in rats. However, the cardiac pacing is required for at least 120–180s to ensure that VF does not spontaneously convert. We can use the technique to establish a new and simpler rat cardiac arrest (CA) model, which may facilitate experimental investigation on CPR. [Copyright &y& Elsevier]

Five novel compounds as potential phosphodiesterase type 5 (PDE‐5) inhibitors were synthesized from D‐tryptophan methyl ester via the Pictet–Spengler reaction and cyclization reaction. The structures of those compounds were confirmed by elemental analyses, IR, 1 H NMR, and ESI‐MS spectra. [ABSTRACT FROM AUTHOR]

Carbon nanotubes (CNTs) production is investigated by the combination of catalyst reduction and methane decomposition over a nickel and a cobalt catalyst in a fluidized bed reactor, respectively. Higher conversion of methane is observed in the combined process of the catalyst reduction and methane decomposition, and the yield of CNTs in the combined process is about 3–4 times that in the separated methane decomposition process. The effect is probably attributed to the lattice oxygen on the unreduced catalyst, in presence of which the simultaneous catalyst reduction provides energy for the endothermic methane decomposition and consumes part of hydrogen and carbon (to the H2O and CO), making the equilibrium of methane decomposition shift to the direction of hydrogen and CNTs production in a much higher reaction rate. [Copyright &y& Elsevier]

Using the Pegg–Barnett formalism of phase operator, we obtain phase probability distributions of new even and odd nonlinear coherent states. It is shown that the distributions for the states are rather different, and unlike the case of ordinary even and odd coherent states the Pegg–Barnett distribution clearly reflects the different character of quantum interference in the case of the new even and odd coherent states. [ABSTRACT FROM AUTHOR]

Carbon nanotubes (CNTs) were prepared by ethylene decomposition on an Fe/Al2O3 catalyst in a fluidized bed reactor. Their gross defects at different growth periods are evaluated by using a combination of SEM, TGA and Raman spectroscopy. The initially grown CNTs have a much lower thermal stability and more defects as compared to the fully-grown ones. The difference in the defects of CNTs at different reaction times is attributed to the lift up of CNTs with the gradually crashing texture of catalyst and the increasing volume of CNTs in a limited reactor space. [Copyright &y& Elsevier]