bluuebunny/crossref_metadata_2025 huggingface dataset:
The Deconstruction of Supramolecular Structures Based on Modular Precise Macromolecules
Authors: Hsu Chih‐Hao , Cheng Stephen Z. D.
Published: November 2017

To rationally design materials with desired properties, a modular approach based on volume‐ and shape‐persistent nanobuilding blocks has been demonstrated recently. Constructing hierarchical supramolecular structures which span several length and energy scales is crucial to transfer and amplify the functionality of nanobuilding blocks to the bulk materials. Determination of soft material self‐assembled structures thus plays a critical role in this approach; however, it is routinely the most time‐consuming step due to the case‐dependent sample preparation and insufficient number of X‐ray and electron diffractions for direct structure determination. A rational thinking pathway for supramolecular structure determination is proposed in this article with covering a variety of essential concepts for a systematic case study. The scope of this article aims to guide newcomers in this field and expedite the molecular design screening for establishing a concrete relationship between molecular design and material properties—a part of the materials genome initiative.
Semicrystalline Shape‐Memory Elastomers: Effects of Molecular Weight, Architecture, and Thermomechanical Path
Authors: Lee Hojun , Yang Jeh‐Chang , Thoppey Nagarajan , Anthamatten Mitchell
Published: November 2017

Poly(caprolactone) networks are well‐studied shape‐memory polymers owing to their high fixity and recovery, their ability to store large amounts of elastic energy, and their tunable shape‐triggering temperature. To elucidate the influence of network structure on shape‐memory features, poly(caprolactone) networks are prepared by reacting different molecular weight diacrylate prepolymers with trifunctional (trimethylolpropane tris(3‐mercaptopropionate), 3T) or tetrafunctional (pentaerythritol tetrakis(3‐mercaptopropionate), 4T) crosslinkers. Networks from 4T crosslinkers generally exhibit higher gel fractions, more elastically active strands, and superior shape‐memory properties compared with networks from 3T. Melted elastomers exhibit stress–strain behavior well described by the neo‐Hookean model. How the state of crystallization during the cold‐drawing process has a large effect on the draw stress, the network's shape fixity, and its elastic storage capacity is shown. Finally, the working strain range of networks is evaluated. Cured elastomers prepared from prepolymers with different molecular weights can store and release large amounts of elastic energy (>2 MJ m−3), over different ranges of tensile strain.
Principal component reconstruction (PCR) for cine CBCT with motion learning from 2D fluoroscopy
Authors: Gao Hao , Zhang Yawei , Ren Lei , Yin Fang‐Fang
Published: November 2017

Purpose

This work aims to generate cine CT images (i.e., 4D images with high‐temporal resolution) based on a novel principal component reconstruction (PCR) technique with motion learning from 2D fluoroscopic training images.

Methods

In the proposed PCR method, the matrix factorization is utilized as an explicit low‐rank regularization of 4D images that are represented as a product of spatial principal components and temporal motion coefficients. The key hypothesis of PCR is that temporal coefficients from 4D images can be reasonably approximated by temporal coefficients learned from 2D fluoroscopic training projections. For this purpose, we can acquire fluoroscopic training projections for a few breathing periods at fixed gantry angles that are free from geometric distortion due to gantry rotation, that is, fluoroscopy‐based motion learning. Such training projections can provide an effective characterization of the breathing motion. The temporal coefficients can be extracted from these training projections and used as priors for PCR, even though principal components from training projections are certainly not the same for these 4D images to be reconstructed. For this purpose, training data are synchronized with reconstruction data using identical real‐time breathing position intervals for projection binning. In terms of image reconstruction, with a priori temporal coefficients, the data fidelity for PCR changes from nonlinear to linear, and consequently, the PCR method is robust and can be solved efficiently. PCR is formulated as a convex optimization problem with the sum of linear data fidelity with respect to spatial principal components and spatiotemporal total variation regularization imposed on 4D image phases. The solution algorithm of PCR is developed based on alternating direction method of multipliers.

Results

The implementation is fully parallelized on GPU with NVIDIA CUDA toolbox and each reconstruction takes about a few minutes. The proposed PCR method is validated and compared with a state‐of‐art method, that is, PICCS, using both simulation and experimental data with the on‐board cone‐beam CT setting. The results demonstrated the feasibility of PCR for cine CBCT and significantly improved reconstruction quality of PCR from PICCS for cine CBCT.

Conclusion

With a priori estimated temporal motion coefficients using fluoroscopic training projections, the PCR method can accurately reconstruct spatial principal components, and then generate cine CT images as a product of temporal motion coefficients and spatial principal components.
TransitQA — A new method for transit dosimetry of Tomotherapy patients
Authors: Pisaturo Olivier , Miéville Frédéric , Tercier Pierre‐Alain , Allal Abdelkarim Said
Published: November 2017

Purpose

TransitQA is an innovative method for Tomotherapy transit dosimetry using the on‐board detector (OBD). Our previously published model for Tomotherapy treatment plan verification (AirQA) has been enhanced to take into account patient and couch transmission. AirQA estimates the OBD signal during irradiation with nothing in the beam path from the leaf control sinogram, allowing us to check whether the planned treatment is correctly delivered by the machine. TransitQA allows us to check the treatment delivery with the patient on the couch, potentially showing the effects of changes in the patient anatomy and delivery errors.

Methods

Patient and couch transmission have been added to the model using the OBD projections of pretreatment megavoltage computed tomography (MVCT). The difference in the energy spectra between the imaging and treatment beams has been corrected by an exponent from the MVCT projections consisting of the ratio of the mass attenuation coefficients. This exponent has been found to not vary significantly with the atomic number Z, allowing us to apply this procedure to heterogeneous media, such as patients. The attenuated OBD projections acquired during the treatment are compared to the model via a signed global γ‐index analysis. The dose criterion was 5% of the 95th percentile of the dose distribution, and the distance to agreement (DTA) was 4 mm.

Results

Our method has been applied to a heterogeneous phantom with 98.1% of the points passing the γ‐evaluation test, showing that the model can predict the attenuated OBD projection. The method has been applied to two representative patients throughout the whole treatment, highlighting variations in the signal transmission and γ‐index.

Conclusion

This paper establishes the proof‐of‐concept of transit dosimetry for all patients treated by Tomotherapy. Moreover, this method can be used as a surrogate for in vivo dosimetry.
Fourier‐based numerical approximation of the Weertman equation for moving dislocations
Authors: Josien Marc , Pellegrini Yves‐Patrick , Legoll Frédéric , Le Bris Claude
Published: November 2017

This work addresses the numerical approximation of solutions to a dimensionless form of the Weertman equation, which models a steadily moving dislocation and is an important extension (with advection term) of the celebrated Peierls‐Nabarro equation for a static dislocation. It belongs to the class of nonlinear reaction‐advection‐diffusion integro‐differential equations with Cauchy‐type kernel, thus involving an integration over an unbounded domain. In the Weertman problem, the unknowns are the shape of the core of the dislocation and the dislocation velocity. The proposed numerical method rests on a time‐dependent formulation that admits the Weertman equation as its long‐time limit. Key features are (1) time iterations are conducted by means of a new, robust, and inexpensive Preconditioned Collocation Scheme in the Fourier domain, which allows for explicit time evolution but amounts to implicit time integration, thus allowing for large time steps; (2) as the integration over the unbounded domain induces a solution with slowly decaying tails of important influence on the overall dislocation shape, the action of the operators at play is evaluated with exact asymptotic estimates of the tails, combined with discrete Fourier transform operations on a finite computational box of size L; (3) a specific device is developed to compute the moving solution in a comoving frame, to minimize the effects of the finite‐box approximation. Applications illustrate the efficiency of the approach for different types of nonlinearities, with systematic assessment of numerical errors. Converged numerical results are found insensitive to the time step, and scaling laws for the combined dependence of the numerical error with respect to L and to the spatial step size are obtained. The method proves fast and accurate and could be applied to a wide variety of equations with moving fronts as solutions; notably, Weertman‐type equations with the Cauchy‐type kernel replaced by a fractional Laplacian.
Facile Fabrication of Nanoparticles Stacked 2,6‐diamino‐3,5‐dinitropyrazine‐1‐oxide (LLM‐105) Sub‐microspheres via Electrospray Deposition
Authors: Huang Chuan , Liu Jiahui , Ding Ling , Wang Dunju , Yang Zhijian , Nie Fude
Published: November 2017

In this study, nanoparticles stacked 2,6‐diamino‐3,5‐dinitropyrazine‐1‐oxide (LLM‐105) sub‐microspheres were successfully fabricated by electrospray deposition. These monodisperse sub‐microspheres with a diameter from 200–500 nm are composed of 50 nm nanoparticles, and after preserved six months these spheres retain the same structure and morphology. The effect of process parameter including flow rate and nozzle size on the size and morphology of sub‐microsphere is investigated. The results show that, for a given solution concentration the nozzle size has little effect while the flow rate shows a significant effect. The X‐ray diffraction (XRD) and Fourier transform infrared spectroscopy (FT‐IR) results exhibit that the as‐prepared sub‐microspheres have the same crystal and chemical structure as the raw materials. The thermal behavior performed by simultaneous thermal analysis (TG‐DSC) verifies that in comparison to the raw materials sub‐microspheres have a lower onset degradation temperature.
A Safer Synthesis of 3,5‐Bis(dinitromethyl)‐1,2,4‐triazole (BDT) and Its Mono and Di Salts: High‐Performance Insensitive Energetic Materials
Authors: Dharavath Srinivas , Shreeve Jean'ne M.
Published: November 2017

Design and synthesis of new insensitive high‐performance energetic materials are significant because of the demands of both civilian and military applications. Now a straightforward route which does not necessitate the use of 1,1‐diamino‐2,2‐dinitroethene (FOX‐7) as a starting material has been developed to synthesize 3,5‐bis(dinitromethyl)‐1,2,4‐triazole (BDT) and its mono and dianion salts. The X‐ray structure of bis‐ triaminoguanidinium 3,5‐bis(dinitromethyl)‐1,2,4‐triazolate (10) further confirms the structure of this dianion. The gem dinitro carbon results in higher packing coefficients and extensive hydrogen bonding interactions. The experimental densities range from 1.66 to 1.93 g cm−3, detonation velocities from 8347 to 9086 ms−1, and pressures from 27.3 to 38.7 GPa, respectively. Some of these values are superior to those of current benchmark explosives, such as 1,3,5‐trinitroperhydro‐1,3,5‐triazine (RDX).
Characterization of forced degradation products of canagliflozine by liquid chromatography/quadrupole time‐of‐flight tandem mass spectrometry and in silico toxicity predictions
Authors: Baira Shandilya Mahamuni , Kalariya Pradipbhai D. , Nimbalkar Rakesh , Garg Prabha , Srinivas R. , Talluri M.V.N. Kumar
Published: November 2017

Rationale

Forced degradation studies are useful for better understanding of the stability of active pharmaceutical ingredients and drugs and to generate information about drug degradation pathways and formation of degradation products (DPs). Identification of DPs plays a vital role in establishing the safety and therapeutic benefit of a drug.

Methods

Canagliflozin (CAN) was subjected to different stress conditions as per International Conference on Harmonization guidelines (Q1A R2). All the DPs and the drug were well separated on an Aquity CSH C18 (100 × 2.1 mm, 1.7 μm) column using acetonitrile–methanol (70:30, v/v) and formic acid in gradient mode. The same UPLC method was employed for LC/HRMS for the characterization of DPs. In addition, in silico toxicity was predicted for all the DPs by using TOPKAT and DEREK software tools.

Results

CAN was found to degrade under oxidative stress condition and formed DP1 and DP2. This is a typical case of degradation where co‐solvents acetonitrile–water (50:50, v/v) and methanol–water (50:50, v/v) react with CAN under acid hydrolytic conditions leading to the formation of pseudo‐DPs, DP3 and DP4, respectively. Among these, DP2 and DP3 showed ocular irritancy whereas DP1 showed skin sensitization.

Conclusions

The drug was labile under oxidative stress condition. CAN reacted with co‐solvent under acid hydrolytic conditions and gave pseudo‐DPs. All the DPs were separated using UPLC and characterized by LC/QTOF/MS/MS. Toxicity of DPs was evaluated using TOPKAT and DEREK software tools.
Anions‐Mediated Morphological Control of Nano‐ /Microscaled Materials: A Case Study of Protonated Melamine‐Based Self‐Assemblies
Authors: Luo Yang‐Hui , Li Yao‐Jia , Chen Chen , Wang Jing‐Wen , An Pei‐Jing , Wu Hong‐Shuai , Sun Bai‐Wang
Published: November 2017

Fabricating of melamine (MM)‐based multi‐component functional self‐assemblies have been investigated intensively. However, studies on protonated MM still in its infancy. Hence in this work, we studied the self‐assembly of protonated MM in different forms (1⋅ClO4− [MMH+⋅ClO4−⋅H2O], 2⋅Br− [MMH2+⋅2Br−⋅H2O], and 3⋅Cl− [MMH2+⋅2Cl−⋅H2O]) with various oxoanions (SO42−, NO3− and PO43−). Results revealed that the original anions ClO4‐, Br‐, and Cl‐, though not included in these self‐assemblies, are mainly responsible for the spectacular morphologies, from cuboids (1.SO42−) to prismoids (2.SO42−), sheets (3.SO42−), fibers (1.NO3−), rods (2.NO3−, 3.NO3−) and ribbons (1.PO43−, 2.PO43−, 3.PO43−). The crystalline phase and compositions of these self‐assemblies were found to be independent from the original protonated MM and the degree of protonation, while depend on the specific oxoanions. Therefore, the self‐assembly mechanism can be proposed. These results may provide an effective strategy for morphological control, especially for further development in protonated MM‐based functional materials.
Asymmetric Fullerene Nanosurfactant: Interface Engineering for Automatic Molecular Alignments
Authors: Kim Dae‐Yoon , Lee Sang‐A , Kim Soeun , Nah Changwoon , Lee Seung Hee , Jeong Kwang‐Un
Published: November 2017

Since the molecular self‐assembly of nanomaterials is sensitive to their surface properties, the molecular packing structure on the surface is essential to build the desired chemical and physical properties of nanomaterials. Here, a new nanosurfactant is proposed for the automatic construction of macroscopic surface alignment layer for liquid crystal (LC) molecules. An asymmetric nanosurfactant (C60NS) consisted of mesogenic cyanobiphenyl moieties with flexible alkyl chains and a [60]fullerene nanoatom is newly designed and precisely synthesized. The C60NS directly introduced in the anisotropic LC medium is self‐assembled into the monolayered protrusions on the surface because of its amphiphilic nature originated by asymmetrically programmed structural motif of LC‐favoring moieties and LC‐repelling groups. The monolayered protrusions constructed by the phase‐separation and self‐assembly of asymmetric C60NS nanosurfactant in the anisotropic LC media amplify and transfer the molecular orientational order from surface to bulk, and finally create the automatic vertical molecular alignment on the macroscopic length scale. The asymmetric C60NS nanosurfactant and its self‐assembly described herein can offer the direct guideline of interface engineering for the automatic molecular alignments.
Design and Biomedical Applications of Poly(amidoamine)‐Dendrimer‐Based Hybrid Nanoarchitectures
Authors: Fan Yu , Sun Wenjie , Shi Xiangyang
Published: November 2017

Dendrimers, especially poly(amidoamine) (PAMAM) dendrimers, possess unique properties such as 3D architecture, monodispersity, highly branched macromolecular characteristics, and tunable terminal functionalities. These properties allow them to be used for controlled synthesis and assembly of hybrid nanoarchitectures with a range of properties suitable for biomedical applications. Here, the recent advances in the design of different PAMAM‐dendrimer‐based hybrid nanoarchitectures for various biomedical applications, in particular for molecular imaging, nonviral gene delivery, and theranostics, are summarized and discussed; future perspectives are also briefly illustrated.
SIRT1 exhibits antioxidative effects in HT22 cells induced by tert‐butyl alcohol
Authors: Ma Junxiang , Song Dongmei , Zhang Yuanyuan , Chen Li , Zhang Shixuan , Jia Jiaxin , Chen Tian , Guo Caixia , Tian Lin , Gao Ai , Niu Piye
Published: November 2017

Tertiary butyl alcohol (TBA) is a principal metabolite of methyl tertiary‐butyl ether (MTBE), a common pollutant worldwide in the ground or underground water, which is found to produce nervous system damage. Nevertheless, few data regarding the effects of TBA has been reported. Studies indicated that oxidative stress plays a pivotal role in MTBE neurotoxic mechanism. Sirtuin 1 (SIRT1) has been reported to exert a neuroprotective effect on various neurologic diseases via resistance to oxidative stress by deacetylating its substrates. In this study, we examined levels of oxidative stress after exposure to TBA for 6 h in HT22 cells and HT22 cells with SIRT1 silencing (transfected with SIRT1 siRNA) or high expression (preconditioned with agonists SRT1720). We found that TBA activated oxidative stress by increasing generation of intracellular reactive oxygen species (ROS), malondialdehyde (MDA) and Oxidized glutathione (GSSG), and decreasing contents of superoxide dismutase (SOD) and glutathione reductase (GSH). In additional, levels of TBA‐induced oxidative stress were aggravated when SIRT1 silenced but alleviated when SIRT1 enhanced. Our study indicated that SIRT1 mitigated oxidative stress induced by TBA.
Fenofibrate induced PPAR alpha expression was attenuated by oestrogen receptor alpha overexpression in Hep3B cells
Authors: Jeng Long‐Bin , Velmurugan Bharath Kumar , Hsu Hsi‐Hsien , Wen Su‐Ying , Shen Chia‐Yao , Lin Chih‐Hao , Lin Yueh‐Min , Chen Ray‐Jade , Kuo Wei‐Wen , Huang Chih‐Yang
Published: November 2017

The physiological regulation of Oestrogen receptor α (ERα) and peroxisome proliferator‐activated receptor alpha (PPARα) in Hepatocellular carcinoma (HCC) remains unknown. The present study we first treat the cells with fenofibrate and further investigated the possible mechanisms of 17β‐estradiol (E2) and/or ERα on regulating PPARα expression. We also found higher PPARα expression in the tumor area than adjacent areas and subsequently compared PPARα expression in four different hepatic cancer cell lines. Hep3B cells were found to express more PPARα than the other cell lines. Using the PPARα agonist fenofibrate, we found that fenofibrate increased Hep3B cell proliferation efficiency by increasing cell cycle proteins, such as cyclin D1 and PCNA, and inhibiting p27 and caspase 3 expressions. Next, we performed transient transfections and immuno‐precipitation studies using the pTRE2/ERα plasmid to evaluate the interaction between ERα and PPARα. ERα interacted directly with PPARα and negatively regulated its function. Moreover, in Tet‐on ERα over‐expressed Hep3B cells, E2 treatment inhibited PPARα, its downstream gene acyl‐CoA oxidase (ACO), cyclin D1 and PCNA expression and further increased p27 and caspase 3 expressions. However, over‐expressed ERα plus 17‐β‐estradiol (10−8 M) reversed the fenofibrate effect and induced apoptosis, which was blocked in ICI/melatonin/fenofibrate‐treated cells. This study illustrates that PPARα expression and function were negatively regulated by ERα expression in Hep3B cells.
Relationship between follicular volume and oocyte competence, blastocyst development and live‐birth rate: optimal follicle size for oocyte retrieval
Authors: Wirleitner B. , Okhowat J. , Vištejnová L. , Králíčková M. , Karlíková M. , Vanderzwalmen P. , Ectors F. , Hradecký L. , Schuff M. , Murtinger M.
Published: November 2017

Objective

To analyze oocyte competence in gonadotropin‐releasing hormone agonist (GnRHa) stimulation cycles with regard to maturity, fertilization and blastocyst rate, as well as clinical outcome (pregnancy and live‐birth rate), in relation to follicular volume, measured by three‐dimensional transvaginal sonography (3D‐TVS), and follicular fluid composition.

Methods

This was a prospective single‐center study conducted between June 2012 and June 2014, including 118 ovum pick‐ups with subsequent embryo transfer. Ovarian stimulation was performed using the GnRHa long protocol. Of 1493 follicles aspirated individually, follicular volume was evaluated successfully in 1236 using automated 3D‐TVS during oocyte retrieval. Oocyte maturity and blastocyst development were tracked according to follicular volume. Intrafollicular concentrations of estradiol, testosterone, progesterone, luteinizing hormone, follicle‐stimulating hormone and granulocyte–colony stimulating factor were quantified by immunoassay. Clinical outcome, in terms of implantation rate, (clinical) pregnancy rate, miscarriage and live‐birth rate (LBR), was evaluated.

Results

Follicles were categorized, according to their volume, into three arbitrary groups, which included 196 small (8–12 mm/0.3–0.9 mL), 772 medium (13–23 mm/1–6 mL) and 268 large (≥ 24 mm/> 6 mL) follicles. Although oocyte recovery rate was significantly lower in small follicles compared with medium and large ones (63.8% vs 76.6% and 81.3%, respectively; P < 0.001), similar fertilization rates (85.1% vs 75.3% and 81.4%, respectively) and blastocyst rates (40.5% vs 40.6% and 37.2%, respectively) per mature metaphase II oocyte were observed. A trend towards higher LBR after transfer of blastocysts derived from small (< 1 mL) follicles compared with medium (1–6 mL) or large (> 6 mL) follicles (54.5% vs 42.0%, and 41.7%, respectively) was observed. No predictive value of follicular fluid biomarkers was identified.

Conclusions

Our data indicate that the optimal follicular volume for a high yield of good quality blastocysts with good potential to lead to a live birth is 13–23 mm/1–6 mL. However, oocytes derived from small follicles (8–12 mm/0.3–0.9 mL) still have the capacity for normal development and subsequent delivery of healthy children, suggesting that aspiration of these follicles should be encouraged as this would increase the total number of blastocysts retrieved per stimulation. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.
Numerical study of the vibrations of an elastic container filled with an inviscid fluid
Authors: Hermant Nicolas , Chouly Franz , Silva Fabrice , Luizard Paul
Published: November 2017

We investigate numerically the vibrational behavior of an elastic structure containing an inviscid fluid with a filling hole where the pressure is prescribed. The underlying mathematical model is detailed and its spectra is characterized. The finite element method relies upon the added‐mass formulation of Morand and Ohayon but avoids the explicit assembly of the dense added‐mass matrix. A parametric study allows to characterize the system's response to dimensionless parameters in terms of eigenfrequencies. The resulting mode shapes are then physically discussed, with emphasis on the presence and the behavior of singular modes caused by specific boundary conditions in the fluid.
Spectral asymptotics of a linearized problem for an incompressible weakly conducting polymeric fluid
Authors: Blokhin Alexander , Tkachev Dmitry , Yegitov Aleksey
Published: November 2017

We deduce a formula of spectral asymptotics of the linearized problem for stationary flows of an incompressible weakly conducting polymeric fluid.
Integrability of generalised type II defects in affine Toda field theory
Authors: Bristow Rebecca
Published: November 2017

Abstract

The Liouville integrability of the generalised type II defects is investigated. Full integrability is not considered, only the existence of an infinite number of conserved quantities associated with a system containing a defect. For defects in affine Toda field theories (ATFTs) it is shown that momentum conservation is very likely to be a necessary condition for integrability. The defect Lax matrices which guarantee zero curvature, and so an infinite number of conserved quantities, are calculated for the momentum conserving Tzitzéica defect and the momentum conserving D
4 ATFT defect. Some additional calculations pertaining to the D
4 defect are also carried out to find a more complete set of defect potentials than has appeared previously.
Postoperative Albumin–Bilirubin Grade Change Predicts the Prognosis of Patients with Hepatitis B‐Related Hepatocellular Carcinoma Within the Milan Criteria
Authors: Li Chuan , Zhang Xiao‐Yun , Peng Wei , Wen Tian‐Fu , Yan Lu‐Nan , Li Bo , Yang Jia‐Yin , Wang Wen‐Tao , Xu Ming‐Qing
Published: November 2017

Objective

Albumin–bilirubin (ALBI) grade has been validated as a simple, evidence‐based, and objective prognostic tool for patients with hepatocellular carcinoma (HCC). However, minimal information is available concerning postoperative ALBI grade changes in HCC. This study aimed to investigate the prognostic value of postoperative ALBI grade changes in patients with hepatitis B virus (HBV)‐related HCC within the Milan criteria after liver resection.

Methods

Patients with HBV‐related HCC within the Milan criteria who underwent liver resection between 2010 and 2016 at West China Hospital were reviewed (N = 258). A change in ALBI grade was defined as first postoperative month ALBI grade–preoperative ALBI grade. If the value was >0, postoperative worsening of ALBI grade was considered; otherwise, stable ALBI grade was considered. Cox proportional hazard regression analyses were used to determine the factors that influence recurrence and survival.

Results

During the follow‐up, 130 patients experienced recurrence and 47 patients died. Multivariate analyses revealed that postoperative worsening of ALBI grade (HR 1.541, 95% CI 1.025–2.318, P = 0.038), microvascular invasion (MVI, HR 1.802, 95% CI 1.205–2.695, P = 0.004), and multiple tumors (HR 1.676, 95% CI 1.075–2.615, P = 0.023) were associated with postoperative recurrence, whereas MVI (HR 2.737, 95% CI 1.475–5.080, P = 0.001), postoperative worsening of ALBI grade (HR 2.268, 95% CI 1.227–4.189, P = 0.009), high alpha‐fetoprotein level (HR 2.055, 95% CI 1.136–3.716, P = 0.017), and transfusion (HR 2.597, 95% CI 1.395–4.834, P = 0.003) negatively influenced long‐term survival. Patients with postoperative worsening of ALBI grade exhibited increased incidence of recurrence and worse long‐term survival.

Conclusion

Postoperative worsening of ALBI grade was associated with increased recurrence and poorer overall survival for patients with HBV‐related HCC within the Milan criteria. We should pay attention to liver function changes in HCC patients after liver resection.
A Survey of Precipitation-Induced Atmospheric Cold Pools over Oceans and Their Interactions with the Larger-Scale Environment
Authors: Zuidema Paquita , Torri Giuseppe , Muller Caroline , Chandra Arunchandra
Published: November 2017

Pools of air cooled by partial rain evaporation span up to several hundreds of kilometers in nature and typically last less than 1 day, ultimately losing their identity to the large-scale flow. These fundamentally differ in character from the radiatively-driven dry pools defining convective aggregation. Advancement in remote sensing and in computer capabilities has promoted exploration of how precipitation-induced cold pool processes modify the convective spectrum and life cycle. This contribution surveys current understanding of such cold pools over the tropical and subtropical oceans. In shallow convection with low rain rates, the cold pools moisten, preserving the near-surface equivalent potential temperature or increasing it if the surface moisture fluxes cannot ventilate beyond the new surface layer; both conditions indicate downdraft origin air from within the boundary layer. When rain rates exceed $$\sim$$
∼
2 mm h$$^{-1}$$

-
1

, convective-scale downdrafts can bring down drier air of lower equivalent potential temperature from above the boundary layer. The resulting density currents facilitate the lifting of locally thermodynamically favorable air and can impose an arc-shaped mesoscale cloud organization. This organization allows clouds capable of reaching 4–5 km within otherwise dry environments. These are more commonly observed in the northern hemisphere trade wind regime, where the flow to the intertropical convergence zone is unimpeded by the equator. Their near-surface air properties share much with those shown from cold pools sampled in the equatorial Indian Ocean. Cold pools are most effective at influencing the mesoscale organization when the atmosphere is moist in the lower free troposphere and dry above, suggesting an optimal range of water vapor paths. Outstanding questions on the relationship between cold pools, their accompanying moisture distribution and cloud cover are detailed further. Near-surface water vapor rings are documented in one model inside but near the cold pool edge; these are not consistent with observations, but do improve with smaller horizontal grid spacings.
Effect of sevoflurane on the ATPase activity of hippocampal neurons in a rat model of cerebral ischemia‐reperfusion injury via the cAMP‐PKA signaling pathway
Authors: Liu Tie‐Jun , Zhang Jin‐Cun , Gao Xiao‐Zeng , Tan Zhi‐Bin , Wang Jian‐Jun , Zhang Pan‐Pan , Cheng Ai‐Bin , Zhang Shu‐Bo
Published: November 2017

We aim to investigate the effects of sevoflurane on the ATPase activity of the hippocampal neurons in rats with cerebral ischemia‐reperfusion injury (IRI) via the cyclic adenosine monophosphate (cAMP) and protein kinase A (PKA) signaling pathway. Sixty rats were assigned into the normal, model and sevoflurane groups (n = 20, the latter two groups were established as focal cerebral IRI models). The ATPase activity was detected using an ultramicro Na (+)‐K (+)‐ATP enzyme kit. Immunohistochemical staining was used to detect the positive protein expression of cAMP and PKA. The hippocampal neurons were assigned to the normal, IRI, IRI + sevoflurane, IRI + forskolin, IRI + H89 and IRI + sevoflurane + H89 groups. qRT‐PCR and Western blotting were performed for the expressions of cAMP, PKA, cAMP‐responsive element‐binding protein (CREB) and brain derived neurotrophic factor (BDNF). The normal and sevoflurane groups exhibited a greater positive protein expression of cAMP and PKA than the model group. Compared with the normal group, the expressions of cAMP, PKA, CREB and BDNF all reduced in the IRI, model and IRI + H89 groups. The sevoflurane group showed higher cAMP, PKA, CREB and BDNF expressions than the model group. Compared with the IRI group, ATPase activity and expressions of cAMP, PKA, CREB and BDNF all increased in the normal, IRI + sevoflurane and IRI + forskolin groups but decreased in the IRI + H89 group. It suggests that sevoflurane could enhance ATPase activity in hippocampal neurons of cerebral IRI rats through activating cAMP‐PKA signaling pathway.
EDITORIAL
Authors: Campbell Marilyn
Published: November 2017

Welcome to the second issue of the journal for 2017. In this issue, we again look at the mental health of students, followed by papers on career guidance and counselling in schools.
Ocean view: a first assessment of the littoral, crustose lichen biota of south Brazil
Authors: APTROOT André , GUMBOSKI Emerson Luiz , CÁCERES Marcela Eugenia da Silva
Published: November 2017

The crustose lichen biota of coastal rocks in South Brazil was investigated. Several distinct lichen zones were found: a littoral black zone, a supralittoral yellow zone and a grey zone with species restricted to either exposed granite, dry overhangs, damp overhangs or places subjected to run-off. Dendrographa austrosorediata is newly described, with a crustose, flat to partly curling up or blister-like thallus which is much dissected, whitish grey, 0·1–0·2 mm thick; surface minutely densely cracked, rimose, with cracks intersecting at each c. 0·1 mm; soredia whitish to bluish grey but asymmetrically blackened in the direction facing the light, originating on the thallus surface, in initially discrete convex soralia. The phylogenetic position of this new species was traced by molecular methods. Stigmidium marinum, generally regarded as a lichenicolous fungus, was found as a free-living lichen, thousands of kilometres away from the nearest known occurrence of any purported host.
The lichen genusRinodina(Physciaceae,Caliciales) in north-eastern Asia
Authors: SHEARD John W. , EZHKIN Alexander K. , GALANINA Irina A. , HIMELBRANT Dmitry , KUZNETSOVA Ekaterina , SHIMIZU Akira , STEPANCHIKOVA Irina , THOR Göran , TØNSBERG Tor , YAKOVCHENKO Lidia S. , SPRIBILLE Toby
Published: November 2017

Rinodinais a widespread, polyphyletic genus of crustosePhysciaceaewithc. 300 species worldwide. A major missing link in understanding its global biogeography has been eastern Asia where the genus has never been systematically revised. Here we review specimen and literature records forRinodinafor north-eastern Asia (Russian Far East, Japan and the Korean Peninsula) and recognize 43 species. We describe two species,R. hypobadiaandR. orientalis, as new to science.Rinodina hypobadiais distinguished by its pigmented hypothecium,Dirinaria-type ascospores and pannarin in both thallus and epihymenium.Rinodina orientalisis characterized by its erumpent apothecia that remain broadly attached, with discs sometimes becoming convex and excluding the thalline margins, ascospores belonging to thePhyscia-type and secondary metabolites absent. Nine other species are reported from the region for the first time. These includeR. dolichospora,R. freyi,R. metaboliza,R. sicula,R. subminutaandR. willeyi. Of particular biogeographical interest are three additional new records that have western North American–eastern Asian distributions: the corticolous speciesR. endospora,R. macrosporaandR. megistospora. Six species have the better known eastern North American–eastern Asian distributions:R. ascociscana(syn.R. akagiensis,R. melancholica),R. buckii,R. chrysidiata,R. subminuta,R. tenuis(syn.R. adirondackii) andR. willeyi, and two have eastern North American–eastern Asian–European distributions:R. excrescensandR. moziana(syn.R. destituta,R. vezdae). Our study begins to close one of the largest gaps in our knowledge of circumboreal species distributions inRinodinaand, together with previous studies in North America and Europe, provides new insights into circumboreal crustose lichen biogeography.Rinodina cinereovirens(syn.R. turfaceavar. cinereovirens) is also reported as new to North America.
Polymorphic fungus-specific microsatellite markers ofBactrospora dryinareveal multiple colonizations of trees
Authors: NADYEINA Olga , ZARABSKA-BOŻEJEWICZ Daria , WIEDMER Andrea , CORNEJO Carolina , SCHEIDEGGER Christoph
Published: November 2017

Bactrospora dryinais an epiphytic lichen-forming fungus specifically related to old-growth floodplain forests, which have dramatically declined in Europe over the past centuries. In order to promote conservation management of such forest remnants, we aimed to study population genetics of this rare and threatened lichen. The newly developed 16 microsatellite markers are specific for the mycobiont ofB. dryinaand reliably amplify either single fruiting bodies or a sterile thallus. This allows the use of these markers for the identification of sterile crusts and for quantification of recent dispersal of the species into restored habitats. We tested the markers in 264 samples collected from 10 pedunculate oak trees growing in three localities in north-eastern Switzerland. All markers were polymorphic and showed two to five alleles per locus, and unbiased gene diversity varied from 0·06 to 0·71 over three populations. The relatively low number of alleles inB. dryinais possibly the consequence of colonization of secondary habitats created by forest management. Although oaks were largely covered with a single, continuousB. dryinacolony, the microsatellite markers identified single or complex multi-genotype colonizations per tree. For future population genetic studies, we recommend collection of 5–15 specimens from one tree which would enable detection of 60–80% of the multilocus genotypes present. Hierarchical AMOVA revealed high variation (70%) on host trees, and a relatively high differentiation (12%) among the three locations in NE Switzerland indicated limited gene flow between those regions. Thus, the newly developed markers showed their applicability in population genetics at different spatial scales. They will play an important role in monitoring habitat restoration for the conservation ofB. dryinaand associated forests and riverscapes.
Build your own soil: exploring microfluidics to create microbial habitat structures
Authors: Aleklett Kristin , Kiers E Toby , Ohlsson Pelle , Shimizu Thomas S , Caldas Victor E A , Hammer Edith C
Published: November 2017

Soil is likely the most complex ecosystem on earth. Despite the global importance and extraordinary diversity of soils, they have been notoriously challenging to study. We show how pioneering microfluidic techniques provide new ways of studying soil microbial ecology by allowing simulation and manipulation of chemical conditions and physical structures at the microscale in soil model habitats.
Development of corticostriatal connectivity constrains goal-directed behavior during adolescence
Authors: Insel Catherine , Kastman Erik K. , Glenn Catherine R. , Somerville Leah H.
Published: November 2017

When pursuing high-value goals, mature individuals typically titrate cognitive performance according to environmental demands. However, it remains unclear whether adolescents similarly integrate value-based goals to selectively enhance goal-directed behavior. We used a value-contingent cognitive control task during fMRI to assess how stakes—the value of a prospective outcome—modulate flexible goal-directed behavior and underlying neurocognitive processes. Here we demonstrate that while adults enhance performance during high stakes, adolescents perform similarly during low and high stakes conditions. The developmental emergence of value-contingent performance is mediated by connectivity between the striatum and prefrontal cortex; this connectivity selectively increases during high stakes and with age. These findings suggest that adolescents may not benefit from high stakes to the same degree adults do—a behavioral profile that may be constrained by ongoing maturation of corticostriatal connectivity. We propose that late development of corticostriatal connectivity sets the stage for optimal goal-directed behavior.
Structural basis for the assembly of the Ragulator-Rag GTPase complex
Authors: Yonehara Ryo , Nada Shigeyuki , Nakai Tomokazu , Nakai Masahiro , Kitamura Ayaka , Ogawa Akira , Nakatsumi Hirokazu , Nakayama Keiichi I. , Li Songling , Standley Daron M. , Yamashita Eiki , Nakagawa Atsushi , Okada Masato
Published: November 2017

The mechanistic target of rapamycin complex 1 (mTORC1) plays a central role in regulating cell growth and metabolism by responding to cellular nutrient conditions. The activity of mTORC1 is controlled by Rag GTPases, which are anchored to lysosomes via Ragulator, a pentameric protein complex consisting of membrane-anchored p18/LAMTOR1 and two roadblock heterodimers. Here we report the crystal structure of Ragulator in complex with the roadblock domains of RagA-C, which helps to elucidate the molecular basis for the regulation of Rag GTPases. In the structure, p18 wraps around the three pairs of roadblock heterodimers to tandemly assemble them onto lysosomes. Cellular and in vitro analyses further demonstrate that p18 is required for Ragulator-Rag GTPase assembly and amino acid-dependent activation of mTORC1. These results establish p18 as a critical organizing scaffold for the Ragulator-Rag GTPase complex, which may provide a platform for nutrient sensing on lysosomes.
Publisher Correction: Tropical explosive volcanic eruptions can trigger El Niño by cooling tropical Africa
Authors: Khodri Myriam , Izumo Takeshi , Vialard Jérôme , Janicot Serge , Cassou Christophe , Lengaigne Matthieu , Mignot Juliette , Gastineau Guillaume , Guilyardi Eric , Lebas Nicolas , Robock Alan , McPhaden Michael J.
Published: November 2017

A correction to this article has been published and is linked from the HTML version of this article.
Programmable DNA looping using engineered bivalent dCas9 complexes
Authors: Hao Nan , Shearwin Keith E. , Dodd Ian B.
Published: November 2017

DNA looping is a ubiquitous and critical feature of gene regulation. Although DNA looping can be efficiently detected, tools to readily manipulate DNA looping are limited. Here we develop CRISPR-based DNA looping reagents for creation of programmable DNA loops. Cleavage-defective Cas9 proteins of different specificity are linked by heterodimerization or translational fusion to create bivalent complexes able to link two separate DNA regions. After model-directed optimization, the reagents are validated using a quantitative DNA looping assay in E. coli. Looping efficiency is ~15% for a 4.7 kb loop, but is significantly improved by loop multiplexing with additional guides. Bivalent dCas9 complexes are also used to activate endogenous norVW genes by rewiring chromosomal DNA to bring distal enhancer elements to the gene promoters. Such reagents should allow manipulation of DNA looping in a variety of cell types, aiding understanding of endogenous loops and enabling creation of new regulatory connections.
Gallstone Disease and the Risk of Type 2 Diabetes
Authors: Lv Jun , Yu Canqing , Guo Yu , Bian Zheng , Yang Ling , Chen Yiping , Li Shanpeng , Huang Yuelong , Fu Yan , He Pan , Tang Aiyu , Chen Junshi , Chen Zhengming , Qi Lu , Li Liming
Published: November 2017

Gallstone disease (GSD) is related to several diabetes risk factors. The present study was to examine whether GSD was independently associated with type 2 diabetes in the China Kadoorie Biobank study. After excluding participants with prevalent diabetes and prior histories of cancer, heart disease, and stroke at baseline, 189,154 men and 272,059 women aged 30–79 years were eligible for analysis. The baseline prevalence of GSD was 5.7% of the included participants. During 4,138,687 person-years of follow-up (median, 9.1 years), a total of 4,735 men and 7,747 women were documented with incident type 2 diabetes. Compared with participants without GSD at baseline, the multivariate-adjusted hazard ratios (HRs) for type 2 diabetes for those with GSD were 1.09 (95% CI: 0.96–1.24; P = 0.206), 1.21 (95% CI: 1.13-1.30; P < 0.001), and 1.17 (95% CI: 1.10-1.25; P < 0.001) in men, women, and the whole cohort respectively. There was no statistically significant heterogeneity between men and women (P = 0.347 for interaction). The association between GSD and type 2 diabetes was strongest among participants who reported ≥5 years since the first diagnosis and were still on treatment at baseline (HR = 1.48; 95% CI: 1.16-1.88; P = 0.001). The present study highlights the importance of developing a novel prevention strategy to mitigate type 2 diabetes through improvement of gastrointestinal health.
Accurate thermal conductivities from optimally short molecular dynamics simulations
Authors: Ercole Loris , Marcolongo Aris , Baroni Stefano
Published: November 2017

The evaluation of transport coefficients in extended systems, such as thermal conductivity or shear viscosity, is known to require impractically long simulations, thus calling for a paradigm shift that would allow to deploy state-of-the-art quantum simulation methods. We introduce a new method to compute these coefficients from optimally short molecular dynamics simulations, based on the Green-Kubo theory of linear response and the cepstral analysis of time series. Information from the full sample power spectrum of the relevant current for a single and relatively short trajectory is leveraged to evaluate and optimally reduce the noise affecting its zero-frequency value, whose expectation is proportional to the corresponding conductivity. Our method is unbiased and consistent, in that both the resulting bias and statistical error can be made arbitrarily small in the long-time limit. A simple data-analysis protocol is proposed and validated with the calculation of thermal conductivities in the paradigmatic cases of elemental and molecular fluids (liquid Ar and H2O) and of crystalline and glassy solids (MgO and a-SiO2). We find that simulation times of one to a few hundred picoseconds are sufficient in these systems to achieve an accuracy of the order of 10% on the estimated thermal conductivities.
Treatment of Myocardial Infarction with Gene-modified Mesenchymal Stem Cells in a Small Molecular Hydrogel
Authors: Wu Zhiye , Chen Guoqin , Zhang Jianwu , Hua Yongquan , Li Jinliang , Liu Bei , Huang Anqing , Li Hekai , Chen Minsheng , Ou Caiwen
Published: November 2017

The effect of transplanted rat mesenchymal stem cells (MSCs) can be reduced by extracellular microenvironment in myocardial infarction (MI). We tested a novel small-molecular hydrogel (SMH) on whether it could provide a scaffold for hepatocyte growth factor (HGF)-modified MSCs and alleviate ventricular remodeling while preserving cardiac function after MI. Overexpression of HGF in MSCs increased Bcl-2 and reduced Bax and caspase-3 levels in response to hypoxia in vitro. Immunocytochemistry demonstrated that cardiac troponin (cTnT), desmin and connexin 43 expression were significantly enhanced in the 5-azacytidine (5-aza) with SMH group compared with the 5-aza only group in vitro and in vivo. Bioluminescent imaging indicated that retention and survival of transplanted cells was highest when MSCs transfected with adenovirus (ad-HGF) were injected with SMH. Heart function and structure improvement were confirmed by echocardiography and histology in the Ad-HGF-SMHs-MSCs group compared to other groups. Our study showed that: HGF alleviated cell apoptosis and promoted MSC growth. SMHs improved stem cell adhesion, survival and myocardial cell differentiation after MSC transplantation. SMHs combined with modified MSCs significantly decreased the scar area and improved cardiac function.