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Status and transport of water in plant body are the main contents of study of soil-plant-atmosphere continuum (SPAC), as well as the base for use and regulation of agricultural water. The process of water transport in plant can be deeply influenced by the environments. Thus, plant needs to adjust its water status to accommodate the environmental change to sustain its own growth and development. Traditional methods for plant water monitoring, such as evaporation flux, pressure chamber, high pressure flow meter, heat pulse, and so on, usually cause damage or even destruction of plant body and disturb the original water status. Thus, they are not able to truly and precisely detect and reflect the real water status of plant. Nuclear magnetic resonance (NMR) is a non-destructive and non-invasive technique which can be used for the measurement of water molecular displacement and transportation. This study aimed to provide an overview of the applications of NMR technique in the study of water distribution and transport in plant roots and stems, as well as the water content in plant cells and tissues. In addition, the existing main problems and possible solutions were analyzed for the applications of NMR in SPAC studies. Several important issues were proposed for the acquisition of more precise and reliable detection signals. It was suggested that the NMR technique would probably make important progress in the relevant fields such as plant water physiology, plant-environment interactions, and water metabolism. In general, the application of NMR in SPAC system study was still in its infancy in China. The deeper application and expansion of NMR in SPAC study would depend on the development of portable and open NMR equipment that could be easily applied for different plants in field. [ABSTRACT FROM AUTHOR]

A/B testing is widely used for comparing two versions of a product and evaluating new proposed product features. It is of great importance for decision-making and has been applied as a golden standard in the IT industry. It is essentially a form of two-sample statistical hypothesis testing. Average treatment effect (ATE) and the corresponding p-value can be obtained under certain assumptions. One key assumption in traditional A/B testing is the stable-unit-treatment-value assumption (SUTVA): there is no interference among different units. It means that the observation on one unit is unaffected by the particular assignment of treatments to the other units. Nonetheless, interference is very common in social network settings where people communicate and spread information to their neighbors. Therefore, the SUTVA assumption is violated. Analysis ignoring this network effect will lead to biased estimation of ATE. Most existing works focus mainly on the design of experiment and data analysis in order to produce estimators with good performance in regards to bias and variance. Little attention has been paid to the calculation of p-value. We work on the calculation of p-value for the ATE estimator in network A/B tests. After a brief review of existing research methods on design of experiment based on graph cluster randomization and different ATE estimation methods, we propose a permutation method for calculating p-value based on permutation test at the cluster level. The effectiveness of the method against that based on individual-level permutation is validated in a simulation study mimicking realistic settings. [ABSTRACT FROM AUTHOR]

Recent studies have revealed that flotillin-1 (FLOT1) plays important roles in cancer progression. However, the role of FLOT1 in development and progression of non-small cell lung cancer (NSCLC) remains largely unknown. The objective of the current study was to investigate the expression pattern and clinicopathological significance of FLOT1 in patients with NSCLC. Real-time quantitative polymerase chain reaction was applied to examine FLOT1 mRNA expression in 52 pairs of NSCLC tissues and adjacent noncancerous tissues. Immunohistochemistry was performed to examine FLOT1 protein expression in paraffin-embedded tissues from 106 NSCLC patients. Statistical analyses were applied to evaluate the diagnostic value and associations of FLOT1 expression with clinicopathological characteristics. FLOT1 mRNA expression was evidently upregulated in NSCLC tissues compared with that in the adjacent noncancerous tissues. In the 106 cases of tested NSCLC samples, FLOT1 protein level was positively correlated with tumor size, tumor stage, and lymph node metastasis. Patients with higher FLOT1 expression had shorter overall survival time, whereas those with lower FLOT1 expression had longer survival time. Taken together, our findings indicate that FLOT1 may play an important role in NSCLC tumorigenesis. Further elucidation of the molecular mechanisms underlying the role of FLOT1 is warranted. [ABSTRACT FROM AUTHOR]

System integrity is important for fast and accurate measurement and control. Lab VIEW is widely used in education and industry. Many Lab VIEW codes are hard to be read and shown because of their 2D topology. In order to simplify the programming, a 4-layer model of developing sensor or measurement systems with Lab VIEW is proposed in this paper. The purpose of this paper is to show the readers how to design simple, clear and strong automated systems with Lab VIEW. Using a Sensirion SHT75 humidity sensor and an NI USB6008 DAQ board as an example, this paper describes the steps of developing a sensor system from the physical layer to application layer in detail. In layer 2, port selection and signal regulation are demonstrated. In layer 3, timing waveform analysis and synthesis, state diagram analysis, instruction set design, micro operation and fault tolerance designs are demonstrated. In layer 4, data visualization is covered with a vivid example. Programmers found it was hard to show readers their Lab VIEW codes because many Lab VIEW codes occupy several screens. A layer model simplifies the programming, so one is able to show a medium size Lab VIEW code easily. [ABSTRACT FROM AUTHOR]

This paper presents a simplified analytical model for predicting nonlinear mechanical responses of flexible composite sheet (FCS) subjected to out-of-plane loading. New geometric model based on three-parameter exponential function is proposed to depict 3D funnel-like geometric shape of out-of-plane loaded FCS, and nonlinear constitutive model is then derived to describe the load-displacement curves of out-of-plane loaded FCS. Finally, model parameters are determined through the principle of minimum potential energy. In order to verify new models, out-of-plane loading tests are performed on PWF (plain woven fabric) polyester reinforced HNR (hydrogenated nitrile rubber) composite sheets with three length-width ratios of 1, 2 and 3, and the predictions agree well with the experiments, demonstrating the practical and effective use of the proposed model. [ABSTRACT FROM AUTHOR]

Background: Sequence signatures, as defined by the frequencies of k-tuples (or k-mers, k-grams), have been used extensively to compare genomic sequences of individual organisms, to identify cis-regulatory modules, and to study the evolution of regulatory sequences. Recently many next-generation sequencing (NGS) read data sets of metagenomic samples from a variety of different environments have been generated. The assembly of these reads can be difficult and analysis methods based on mapping reads to genes or pathways are also restricted by the availability and completeness of existing databases. Sequence-signature-based methods, however, do not need the complete genomes or existing databases and thus, can potentially be very useful for the comparison of metagenomic samples using NGS read data. Still, the applications of sequence signature methods for the comparison of metagenomic samples have not been well studied. Results: We studied several dissimilarity measures, including d2, d2* and d2S recently developed from our group, a measure (hereinafter noted as Hao) used in CVTree developed from Hao's group (Qi et al., 2004), measures based on relative di-, tri-, and tetra-nucleotide frequencies as in Willner et al. (2009), as well as standard lp measures between the frequency vectors, for the comparison of metagenomic samples using sequence signatures. We compared their performance using a series of extensive simulations and three real next-generation sequencing (NGS) metagenomic datasets: 39 fecal samples from 33 mammalian host species, 56 marine samples across the world, and 13 fecal samples from human individuals. Results showed that the dissimilarity measure d2S can achieve superior performance when comparing metagenomic samples by clustering them into different groups as well as recovering environmental gradients affecting microbial samples. New insights into the environmental factors affecting microbial compositions in metagenomic samples are obtained through the analyses. Our results show that sequence signatures of the mammalian gut are closely associated with diet and gut physiology of the mammals, and that sequence signatures of marine communities are closely related to location and temperature. Conclusions: Sequence signatures can successfully reveal major group and gradient relationships among metagenomic samples from NGS reads without alignment to reference databases. The d2S dissimilarity measure is a good choice in all application scenarios. The optimal choice of tuple size depends on sequencing depth, but it is quite robust within a range of choices for moderate sequencing depths. [ABSTRACT FROM AUTHOR]

Thin-walled deployable composite hinges (DCHs) can achieve foldable and deployable functions by storing and releasing strain energy, which have great application potential in deployable structures, such as satellite antennas and solar wings. This paper presented multi-objective optimisation designs for DCHs. Firstly, an optimisation problem was established to obtain three conflicting objectives, minimising the peak folding moment, maximising the peak torsional moment and minimising the mass. Three design variables and one constraint had been considered. Moreover, four surrogate models were employed, including response surface methodology (RSM) and machine learning models. Root mean square error (RMSE), mean absolute error (MAE) and correlation coefficient (R2) were used to determine the surrogate model with the highest accuracy. Furthermore, four state-of-the-art Genetic Algorithms were benchmarked to obtain the optimal designs. The mimicked inverted generational distance (mIGD) was applied to determine the best optimiser. The research results have significance to practical engineering application of DCHs. [ABSTRACT FROM AUTHOR]

Foldable and deployable flexible composite thin-walled structures have the characteristics of light weight, excellent mechanical properties and large deformation ability, which means they have good application prospects in the aerospace field. In this paper, a simplified theoretical model for predicting the position of the neutral section of a lenticular deployable composite boom (DCB) in tensile deformation is proposed. The three-dimensional lenticular DCB is simplified as a two-dimensional spring system and a rigid rod, distributed in parallel along the length direction. The position of the neutral cross-section can be determined by solving the balance equations and geometric relations. In order to verify the validity of the theoretical model, a finite element model of the tensile deformation of a lenticular DCB was established. The theoretical prediction results were compared with the finite element calculation results, and the two results were in good agreement. [ABSTRACT FROM AUTHOR]

Composite helical structures (CHSs) can store and release strain energy through elastic deformation, which have been used in automobile and aerospace structures. The compressive stiffness to weight ratio is the core in the design of these structures, requiring an optimal geometric configuration. Seven state-of-the-art Genetic Algorithms were employed and benchmarked to optimise two conflicting objectives, maximising the compressive stiffness while minimising the weight. All design variables that having effects on the compressive stiffness and weight of CHSs had been considered, which are the helix angle, the number of active coils, the helix diameter, the outer and inner diameter of cross-section, and the ply angle. A quantitative analysis method, mimicked inverted generational distance (mIGD), was used to determine the best practice of Genetic Algorithms. This study shows the selection of the Genetic Algorithm is crucial and multi-objective evolutionary algorithm based on decomposition (MOEA/D) is the best solver on searching the designs of the maximum compressive stiffness and the minimum weight. [ABSTRACT FROM AUTHOR]

• An new analytical model considering geometric nonlinearity effect for predicting compressive behaviour (i.e. stiffness, strength and load–displacement relationship) of composite helical structures (CHS) was proposed. • The new analytical model was compared with the classical Wahl model. • Predicted results using the new analytical model correlated well with the experimental data, especially for CHS with large helix angle, it had better prediction accuracy and wider application range. Composite helical structures (CHS) can store and release strain energy through elastic deformation, which has a good application prospect in automobile, aerospace and other fields, such as shock-absorbing spring, deployable antenna, etc. Compressive behaviour (i.e. stiffness, strength and load–displacement relationship) is one of the most important basic mechanical properties of CHS. In order to accurately predict the compressive behaviour of CHS, this paper proposes a new analytical model considering geometric nonlinearity effect. In the geometric model, the geometric parameters of CHS change continuously with the increase of compressive load. The load–displacement relationship considering geometric nonlinearity is deduced by accumulative compressive load increment and accumulative compressive deformation increment. The compressive stiffness of CHS is obtained using linear fitting with least square method. On this basis, the analytical expression of compressive strength of CHS is derived. The predicted results are compared with experimental data from literatures. It is shown that predictions using the new analytical model correlated well with experimental results. Considering geometric nonlinearity effect in the analytical model can predict the compressive behaviour of CHS more accurately. The analytical model is used to further analyze influences of helix angle and helix diameter on the compressive behaviour of CHS. [ABSTRACT FROM AUTHOR]

Difficult-to-access 4-bromo quinolines are constructed directly from easily prepared ortho-propynol phenyl azides using TMSBr as acid-promoter. The cascade transformation performs smoothly to generate desired products in moderate to excellent yields with good functional groups compatibility. Notably, TMSBr not only acted as an acid-promoter to initiate the reaction, and also as a nucleophile. In addition, 4-bromo quinolines as key intermediates could further undergo the coupling reactions or nucleophilic reactions to provide a variety of functionalized compounds with molecular diversity at C4 position of quinolines. [ABSTRACT FROM AUTHOR]

An efficient approach for the synthesis of phosphorylated isoindoline fused with triazoles via Zn(OTf)2-catalyzed cascade cyclization of easily prepared ortho–propynol benzyl azides and diarylphosphine oxides is developed. The transformation occurred smoothly in moderate to excellent yields and tolerated various propargylic alcohol substrates. [ABSTRACT FROM AUTHOR]

We present low-temperature magnetization, magnetoresistance and specific heat measurements on the Kondo lattice compound CePt3P under applied magnetic fields up to 9.0 T. At zero field, CePt3P exhibits a moderately enhanced Sommerfeld coefficient of electronic specific heat γ Ce = 86 mJ/mol·K2 as well as two successive magnetic transitions of Ce 4f moments: an antiferromagnetic ordering at T N1 = 3.0K and a spin reorientation at T N2 = 1.9 K. The value of T N1 shifts to lower temperature as magnetic field increases, and it is ultimately suppressed around B c ∼ 3.0T at 1.5 K. No evidence of non-Fermi liquid behavior is observed around B c down to the lowest temperature measured. Moreover, γ decreases monotonously with increasing the magnetic field. On the other hand, the electrical resistivity shows an anomalous temperature dependence ρ ∝ T n with the exponent n decreasing monotonously from ∼2.6 around B c down to ∼1.7 for B = 9.0 T. The T–B phase diagram constructed from the present experimental results of CePt3P does not match the quantum criticality scenario of heavy fermion systems. [ABSTRACT FROM AUTHOR]

A new and convenient protocol is presented here for the synthesis of 3,6,8-tribromoquinolines via cascade cyclization of N -(3-phenylprop-2-ynyl)anilines employing N -bromosuccinimide as an electrophile. The metal-free process is carried out under mild conditions and is compatible with a variety of substituents. The Sonogashira coupling reaction regioselectively occurs at position C-6 of the obtained products. [ABSTRACT FROM AUTHOR]

C40H28O4P2, monoclinic, P21/c (no. 4), a = 10.651(3) Å, b = 16.702(5) Å, c = 11.352(4) Å, β = 112.985(5)°, V = 1859.1(10) Å3, Z = 2, Rgt(F) = 0.0807, wRref(F2) = 0.2281, T = 296 K. [ABSTRACT FROM AUTHOR]

Rigidly planar polycyclic phosphacycles featuring an internal dioxaphosphorane are promising photofunctional materials. However, the lack of efficient synthetic methods resulted in limited structural diversities which significantly hampered extensive study. Herein, we report a straightforward three‐component synthesis of novel dioxaphosphorane‐fused diphosphacycles with distinctive photophysical properties. Control experiments and theory calculations were performed to account for a plausible reaction mechanism. We also systematically investigated the structure‐property relationships of these unprecedented platforms by combining experiments (X‐ray analysis, optical and redox properties) and theoretical computations. Based on their unique structure and properties, a novel fluorescent switch for pH sensing was revealed by a dynamic ring‐opening/ring‐closing process. [ABSTRACT FROM AUTHOR]

• Experimental longitudinal tensile stress–strain curves fluctuated obviously before final failure. • Micromechanical model considers the dispersions of fiber strength and spatial distributions. • Predicted stress–strain curves agree well with experiments in modulus, initial failure and final failure. • Simulations show the progressive failure process of fibers before the final failure of the unidirectional composite. Longitudinal tensile failure prediction has always been the focus of research on unidirectional (UD) Carbon Fiber Reinforced Polymer (CFRP). In this paper, the longitudinal tensile tests of unidirectional T800 grade carbon fiber reinforced epoxy resin composite were carried out first. The experimental stress–strain curves show that there are obvious progressive damages before the final failures of the specimens. However, this phenomenon is usually neglected in most of the existing investigations and tests to only obtain elastic modulus and ultimate strength. Thus, a Representative Volume Element (RVE) model based on micromechanics was established using finite element method, considering the randomness of fiber spatial distribution and fiber strength. The tensile strength of fiber monofilaments was assumed to follow a statistical two-parameter Weibull distribution. The failure process of UD composite under longitudinal tensile load was simulated by explicit finite element method. The stress–strain curves obtained by simulation are in good agreement with the experimental results. Finally, the influence of different boundary conditions on the calculation of the RVE was studied. It is found that the final failure strengths of the RVE with uniform displacement boundary conditions are similar to the case of periodic boundary conditions, while the former has higher computational efficiency. [ABSTRACT FROM AUTHOR]

The purpose of this study was to explore the learning curve of pediatric surgeons with a skilled laparoscopic basis for laparoscopic Ladd's procedure to treat children with intestinal malrotation. From April 2015 to February 2020, a total of 35 consecutive children who underwent laparoscopic Ladd's procedure for intestinal malrotation performed by the same surgeon were included in this study. The learning curve was analyzed using the cumulative sum (CUSUM) method. This method was used for all 35 cases, taking into account operation time, estimated blood loss, time to start eating after operation, postoperative hospital stay, and postoperative complication rate. All 35 children completed the Ladd's procedure through laparoscopy, and there was no transfer to opening. The CUSUM learning curve was best modeled as a polynomial with equation y=1.1842+1.8625x−0.0365x2−0.0006x3, with goodness-of-fit (R2) as 0.987. The fitting curve slope turned into negative at the 17th case, and the learning curves were divided into learning stage (phase I, case number 1–17, n=17) and mastery stage (phase II, case number 18–35, n=18) with 17 cases as the cutoff point. The operation time, estimated blood loss, time to start eating after operation, and postoperative complication rate in phase II were significantly better than that in phase I, and the difference was statistically significant (all P<0.05). For pediatric surgeons with skilled laparoscopic basis, the learning curve of laparoscopic Ladd's procedure for children with intestinal malrotation was 17 cases. [ABSTRACT FROM AUTHOR]