bluuebunny/crossref_metadata_2025_split huggingface dataset:
Photodeformable Azobenzene‐Containing Liquid Crystal Polymers and Soft Actuators
Authors: Pang Xinlei , Lv Jiu‐an , Zhu Chongyu , Qin Lang , Yu Yanlei 
Published: October 2019

AbstractPhotodeformable liquid crystal polymers (LCPs) that adapt their shapes in response to light have aroused a dramatic growth of interest in the past decades, since light as a stimulus enables the remote control and diverse deformations of materials. This review focuses on the growing research on photodeformable LCPs, including their basic actuation mechanisms, the various deformation modes, the newly designed molecular structures, and the improvement of processing techniques. Special attention is devoted to the novel molecular structures of LCPs, which allow for easy processing and alignment. The soft actuators with various deformation modes such as bending, twisting, and rolling in response to light are also covered with the emphasis on their photo‐induced bionic functions. Potential applications in energy harvesting, self‐cleaning surfaces, sensors, and photo‐controlled microfluidics are further illustrated. The existing challenges and future directions are discussed at the end of this review.
Polariton Photonics Using Structured Metals and 2D Materials
Authors: Cai Ziqiang , Xu Yihao , Wang Chuangtang , Liu Yongmin 
Published: October 2019

AbstractPolaritons are quasiparticles originating from strong interactions between photons and elementary excitations that could enable high tunability, tight electromagnetic field confinement, and large density of photonic states, making it possible to achieve novel and otherwise inaccessible functionalities. For these reasons, polaritons spawn great interest in the fields of physics, materials science, and optics for both fundamental studies as well as potential applications (e.g., modulators, photodetectors, photoluminescence, etc.). In recent years, the explosive growth of research in graphene and other 2D van der Waals materials is witnessed because they provide a new platform that substantially complements conventional metals, dielectrics, and semiconductors to investigate different polariton modes. This review highlights the works published in recent years on the topic of polariton photonics based on structured metals, graphene, and transition‐metal dichalcogenides (TMDs). The exotic optical properties of the polaritons in metallic structures and 2D van der Waals materials offer bright prospects for the development of high‐performance photonic and optoelectronic devices.
Selecting Appropriate Clustering Methods for Materials Science Applications of Machine Learning
Authors: Parker Amanda J. , Barnard Amanda S. 
Published: October 2019

AbstractBased on a general definition of a cluster and the quality of a clustering result, a new method for evaluating existing clustering algorithms, or undertaking clustering, capable of predicting the number and type of clusters and outliers present in a data set, regardless of the complexity of the distribution of points, is presented. This algorithm, referred to as iterative label spreading, can recognize the characteristics expected of a successful clustering result before any clustering algorithm is applied, providing a type of hyper‐parameter optimization for clustering. The efficacy of the algorithm, and the assessment of clustering result, are both confirmed using large benchmark two dimensional synthetic data sets, and small multidimensional data describing a set of silver nanoparticles. It is shown that the method is ideal for studying noisy data with high dimensionality and high variance, typical of data captured in materials and nanoscience.
Directed evolution methods for overcoming trade‐offs between protein activity and stability
Authors: Stimple Samuel D. , Smith Matthew D. , Tessier Peter M. 
Published: October 2019

AbstractEngineered proteins are being widely developed and employed in applications ranging from enzyme catalysts to therapeutic antibodies. Directed evolution, an iterative experimental process composed of mutagenesis and library screening, is a powerful technique for enhancing existing protein activities and generating entirely new ones not observed in nature. However, the process of accumulating mutations for enhanced protein activity requires chemical and structural changes that are often destabilizing, and low protein stability is a significant barrier to achieving large enhancements in activity during multiple rounds of directed evolution. Here we highlight advances in understanding the origins of protein activity/stability trade‐offs for two important classes of proteins (enzymes and antibodies) as well as innovative experimental and computational methods for overcoming such trade‐offs. These advances hold great potential for improving the generation of highly active and stable proteins that are needed to address key challenges related to human health, energy and the environment.
Composite double network hydrogels with thermoresponsive colloidal nanoemulsions
Authors: Kass Lauren , Cardenas‐Vasquez Ernesto Daniel , Hsiao Lilian C. 
Published: October 2019

AbstractWe report the formulation and mechanical characterization of double network (DN) composite hydrogels. The first network consists of covalently crosslinked poly(ethylene glycol diacrylate) (PEGDA), which forms a strong, brittle network that provides elasticity to the gel. The second network, sodium alginate, is ionically crosslinked with Ca2+ to allow increased dissipation of mechanical energy. The novelty of this system over existing DN hydrogels is the additional incorporation of a third mesoscale network, composed of thermoresponsive poly(dimethyl siloxane) (PDMS) nanoemulsions, which undergo colloidal gelation through the bridging of the PEGDA hydrophobic end groups into the PDMS droplets. The colloidally gelled microstructures are photopolymerized into a solid hydrogel by crosslinking the precursors with ultraviolet (UV) light. Tensile mechanical experiments performed on the crosslinked DN nanoemulsion hydrogels show that their rupture stress (0.17–0.34 MPa), fracture energy (144–421 J/m2), and Young's modulus (1–2.1 MPa) are comparable to similar systems in the literature. These mechanical measurements suggest that the gels may be suitable for manufacturing processes in which large shear rates and deformations are encountered.
Quantitative analysis of CO2 hydrate formation in porous media by proton NMR
Authors: Zheng Jia‐nan , Yang Lei , Ma Shihui , Zhao Yuechao , Yang Mingjun 
Published: October 2019

AbstractGas hydrate is a nonstoichiometric crystal compound formed from water and gas. Most nonvisual studies on gas hydrate are unable to detect how much water is converted to hydrates, and thus, the hydrate stoichiometry calculations are inaccurate. This study investigated the CO2 hydrate formation process in porous media directly and quantitatively. The characteristics of the time‐variable consumption of hydrate formation indicated a two‐stage formation, hydrate enclathration and continuous occupancy. The enclathration stage occurred in the first 20 min of the formation when considerable heat is released. The continuous occupancy stage lasted longer than the hydrate enclathration because the empty cages in previously formed hydrates would also be occupied. The higher formation pressures can accelerate water consumption and increase cage occupancy. The compositions of completely formed CO2 hydrates at 2.7, 3.0, and 3.3 MPa and 275.15 K were determined as CO2·6.90H2O, CO2·6.70H2O, and CO2·6.49H2O, respectively.
Philadelphia chromosome‐positive acute lymphoblastic leukemia at first relapse in the era of tyrosine kinase inhibitors
Authors: Abou Dalle Iman , Kantarjian Hagop M. , Short Nicholas J. , Konopleva Marina , Jain Nitin , Garcia‐Manero Guillermo , Garris Rebecca , Qiao Wei , Cortes Jorge E. , O'Brien Susan , Kebriaei Partow , Kadia Tapan , Jabbour Elias , Ravandi Farhad 
Published: October 2019

AbstractDespite the advances in the management of Philadelphia chromosome‐positive (Ph+) acute lymphoblastic leukemia (ALL) with the introduction of tyrosine kinase inhibitors (TKIs), relapses remain challenging. We reviewed clinical data from adult patients with Ph + ALL who received frontline hyperCVAD chemotherapy with a TKI to determine their outcomes after first relapse. Patients with first morphological relapse after prior complete remission were evaluated for predictors of response and survival. For 57 of 233 (25%) patients, there was morphological relapse after a median of 15.9 months from first remission [range: 5.3‐94]. The choice of salvage treatments was at the discretion of the treating physician. So, 43 (75%) patients received a TKI in combination with their salvage treatment. Second remission was achieved in 41 of 49 (84%) evaluable patients. Median relapse free survival (RFS) was 10.5 months [range, 0.2‐81]. The 1‐year and 2‐year overall survival (OS) were 41% and 20% respectively. On multivariate analysis, only elevated LDH (units/L), the use of first‐generation or no TKI at the time of first relapse and the achievement of a major molecular response (MMR) had a significant effect on OS (HR: 2.82, 95% CI:1.11‐7.16, P = .029; HR = 2.39, 95% CI: 1.07,5.39, P = .034; HR = 0.39, 95% CI: 0.16‐0.94, P = .03, respectively). Whereas, only achievement of MMR was significantly prognostic for RFS with a HR of 0.48 (95% CI: 0.23‐0.98, P = .04). The OS and RFS were comparable between recipients and non‐recipients of allogeneic hematopoietic stem cell transplantation (alloHSCT) at second remission, due to a higher non‐relapse mortality (53%) seen in patients who underwent alloHSCT.
Freshwater ecosystem vulnerability: Is native climatic niche good enough to predict invasion events?
Authors: Frederico Renata G. , Salvador Gilberto N. , Andrade André , Rosa Gustavo R. , Torquato Gabriel V. 
Published: October 2019

Abstract

The introduction of invasive species is a significant threat to freshwater ecosystems and is changing the biogeographic patterns of fish species, leading to homogenization of fish fauna. The ability to predict potential invasions is critical in conservation biology to avoid further biodiversity loss.
Ecological niche modelling has become an important tool in biological invasion studies. However, some introduced species can spread to habitats that are different from those in their native range.
A framework based on niche shifts and ecological niche models was used to show that Pterygoplichthys ambrosettii, an armoured catfish, commonly known as ‘pleco', and native to the middle‐lower Paraná river, has expanded its niche by 27% and is now occupying a new range of environmental conditions.
This species has experienced a niche shift from its original habitat and has started to occupy new areas of the Upper Paraná river basin and the São Francisco basin in Brazil. Models built using both native and non‐native areas were not able to predict the invaded habitats, and in either the native or non‐native areas the cross‐validation procedures corroborate the niche expansion hypothesis.
Klebsiella pneumoniae Redistributes Katanin Severing Proteins and Alters Astral Microtubules during Mitosis
Authors: Chua Michael D. , Bogdan Alexander C. , Guttman Julian A. 
Published: October 2019

ABSTRACTKlebsiella pneumoniae has become a growing concern within hospitals due to multidrug resistant strains and increasing mortality rates. Recently, we showed that at the subcellular level, K. pneumoniae compromises the integrity of the epithelia by disassembling the microtubule networks of cells through the actions of katanin microtubule severing proteins. In this study, we report on the observation that mitotic cells are targeted by K. pneumoniae and that during infections, the katanin proteins are excluded from the microtubule organizing centers of dividing cells, resulting in the alteration of the microtubule cytoskeleton. Anat Rec, 2019. © 2019 American Association for Anatomy Anat Rec, 303:1859–1864, 2020. © 2019 American Association for Anatomy
Benzoxazole/benzothiazole‐derived VEGFR‐2 inhibitors: Design, synthesis, molecular docking, and anticancer evaluations
Authors: El‐Helby Abdel‐Ghany A. , Sakr Helmy , Eissa Ibrahim H. , Al‐Karmalawy Ahmed A. , El‐Adl Khaled 
Published: October 2019

AbstractA novel series of benzoxazole/benzothiazole derivatives 4a–c–11a–e were designed, synthesized, and evaluated for anticancer activity against HepG2, HCT‐116, and MCF‐7 cells. HCT‐116 was the most sensitive cell line to the influence of the new derivatives. In particular, compound 4c was found to be the most potent derivative against HepG2, HCT‐116, and MCF‐7 cells, with IC50 values = 9.45 ± 0.8, 5.76 ± 0.4, and 7.36 ± 0.5 µM, respectively. Compounds 4b, 9f, and 9c showed the highest anticancer activities against HepG2 cells with IC50 values of 9.97 ± 0.8, 9.99 ± 0.8, and 11.02 ± 1.0 µM, respectively, HCT‐116 cells with IC50 values of 6.99 ± 0.5, 7.44 ± 0.4, and 8.15 ± 0.8 µM, respectively, and MCF‐7 cells with IC50 values of 7.89 ± 0.7, 8.24 ± 0.7, and 9.32 ± 0.7 µM, respectively, in comparison with sorafenib as reference drug with IC50 values of 9.18 ± 0.6, 5.47 ± 0.3, and 7.26 ± 0.3 µM, respectively. The most active compounds 4a–c, 9b,c,e,f,h, and 11c,e were further evaluated for their VEGFR‐2 inhibition. Compounds 4c and 4b potently inhibited VEGFR‐2 at IC50 values of 0.12 ± 0.01 and 0.13 ± 0.02 µM, respectively, which are nearly equipotent to the sorafenib IC50 value (0.10 ± 0.02 µM). Furthermore, molecular docking studies were performed for all synthesized compounds to assess their binding pattern and affinity toward the VEGFR‐2 active site.
Measuring Ultrafast Spectral Diffusion and Correlation Dynamics by Two‐Dimensional Electronic Spectroscopy
Authors: Do Thanh Nhut , Khyasudeen M. Faisal , Nowakowski Paweł J. , Zhang Zhengyang , Tan Howe‐Siang 
Published: October 2019

AbstractThe frequency fluctuation correlation function (FFCF) measures the spectral diffusion of a state's transition while the frequency fluctuation cross‐correlation function (FXCF) measures the correlation dynamics between the transitions of two separate states. These quantities contain a wealth of information on how the chromophores or excitonic states interact and couple with its environment and with each other. We summarize the experimental implementations and theoretical considerations of using two‐dimensional electronic spectroscopy to characterize FFCFs and FXCFs. Applications can be found in systems such as the chlorophyll pigment molecules in light‐harvesting complexes and CdSe nanomaterials.
Synthesis of Low‐Viscosity Ionic Liquids for Application in Dye‐Sensitized Solar Cells
Authors: Fang Yanyan , Ma Pin , Cheng Hongbo , Tan Guoyu , Wu Jiaxin , Zheng Jiaxin , Zhou Xiaowen , Fang Shibi , Dai Yuhua , Lin Yuan 
Published: October 2019

AbstractTwo types of ionic liquids (ILs), 1‐(3‐hexenyl)‐3‐methyl imidazolium iodide and 1‐(3‐butenyl)‐3‐methyl imidazolium iodide, are synthesized by introducing an unsaturated bond into the side alkyl chain of the imidazolium cation. These new ionic liquids exhibit high thermal stability and low viscosity (104 cP and 80 cP, respectively). The molecular dynamics simulation shows that the double bond introduced in the alkane chain greatly changes the molecular system space arrangement and diminishes the packing efficiency, leading to low viscosity. The low viscosity of the synthesized ionic liquids would enhance the diffusion of redox couples. This enhancement is detected by fabricating dye‐sensitized solar cells (DSSCs) with electrolytes containing the two ILs and I2. The highest efficiency of DSSCs is 6.85 % for 1‐(3‐hexenyl)‐3‐methyl imidazolium iodide and 5.93 % for 1‐(3‐butenyl)‐3‐methyl imidazolium iodide electrolyte, which is much higher than that of 5.17 % with the counterpart 1‐hexyl‐3‐methyl imidazolium iodide electrolyte.
Facile Synthesis of PdCu Echinus‐Like Nanocrystals as Robust Electrocatalysts for Methanol Oxidation Reaction
Authors: Zhang Zhicheng , Ren Guohong , Liu Yajun , Liang Ying , Wang Mingqian , Wu Shishan , Shen Jian 
Published: October 2019

AbstractExploiting high‐performance and inexpensive electrocatalysts for methanol electro‐oxidation is conductive to promoting the commercial application of direct methanol fuel cells. Here, we present a facile synthesis of echinus‐like PdCu nanocrystals (NCs) via a one‐step and template‐free method. The echinus‐like PdCu NCs possess numerous straight and long branches which can provide abundant catalytic active sites. Owing to the novel nanoarchitecture and electronic effect of the PdCu alloy, the echinus‐like PdCu NCs display high electrocatalytic performance toward methanol oxidation reaction in an alkaline medium. The mass activity of echinus‐like PdCu NCs is 1202.1 mA mgPd−1, which is 3.7 times that of Pd/C catalysts. In addition, the echinus‐like structure, as a kind of three‐dimensional self‐supported nanoarchitecture, endows PdCu NCs with significantly enhanced stability and durability. Hence, the echinus‐like PdCu NCs hold prospect of being employed as electrocatalysts for direct alcohol fuel cells.
Finite Horizon Maximum Likelihood Estimation for Integrated Navigation with RF Beacon Measurements
Authors: Shankar Sharad , Ezal Kenan , Hespanha João P. 
Published: October 2019

AbstractWe develop a Finite Horizon Maximum Likelihood Estimator (FHMLE) that fuses Inertial Measurement Unit (IMU) and radio frequency (RF) measurements over a sliding window of finite length for three‐dimensional navigation. Available RF data includes pseudo–ranges, angles of transmission (AoT), and Doppler shift measurements. The navigation estimates are obtained by solving a finite‐dimensional nonlinear optimization using a primal‐dual interior point algorithm (PDIP). The benefits of the proposed estimation method are highlighted using simulations results comparing the FHMLE approach with an Unscented Kalman Filter (UKF), in a scenario where an aircraft approaches a carrier, with RF measurements from beacons aboard the carrier, and low‐cost IMU measurements aboard the aircraft. When the Geometric Dilution of Precision is large, we found that the FHMLE is able to achieve smaller estimation errors than the UKF, which tends to carry a bias throughout the trajectory.
Multivariable integral linear quadratic Gaussian robust control of islanded microgrid to mitigate voltage oscillation for improving transient response
Authors: Sarker Subrata K. , Badal Faisal R. , Das Purnima , Das Sajal K. 
Published: October 2019

AbstractA novel robust integral linear quadratic Gaussian (ILQG) controller is presented in this paper to control the voltage of islanded microgrid and improves its transient response. Microgrid is a small grid that consists of number of distributed generator units, power‐electronic components with inductor‐capacitor (LC) filters and loads. The loads are parametrically uncertain and unknown that produces the voltage or power oscillation. The ILQG controller is capable to compensate for the voltage oscillation and exhibits the tracking of grid voltage against the different load dynamics. The design of ILQG controller is carried out by augmenting the plant dynamics with an integrator. The robustness of the ILQG controller is studied by considering a number of uncertainties within the plant model. The performance of ILQG controller is compared with linear quadratic regulator (LQR) and linear quadratic Gaussian (LQG) controller in terms of rise time, settling time, bandwidth and tracking error. The comparison results ensure the high bandwidth and tracking performance of ILQG controller as compared to other controllers.
Socioeconomic disparities in timeliness of care and outcomes for anal cancer patients
Authors: Ahmad Tessnim R. , Susko Matthew , Lindquist Karla , Anwar Mekhail 
Published: October 2019

AbstractBackgroundSocioeconomic status (SES) is associated with diagnostic and treatment delays and survival in multiple cancers, but less data exist for anal squamous cell carcinoma (ASCC). This study investigated the association between SES and outcomes for patients undergoing definitive chemoradiation therapy for ASCC.MethodsOne hundred and eleven patients diagnosed with nonmetastatic ASCC between 2005 and 2018 were retrospectively reviewed. Socioeconomic predictor variables included primary payer, race, income, employment, and partnership status. Outcomes included the tumor‐node (TN) stage at diagnosis, the duration from diagnosis to treatment initiation, relapse‐free survival (RFS), and overall survival (OS). Age, gender, TN stage, and HIV status were analyzed as covariates in survival analysis.ResultsSES was not associated with the TN stage at diagnosis. SES factors associated with treatment initiation delays were Medicaid payer (P = .016) and single partnership status (P = .016). Compared to privately insured patients, Medicaid patients had lower 2‐year RFS (64.4% vs 93.8%, P = .021) and OS (82.9% vs 93.5%, P = .038). Similarly, relative to patients in the racial majority, racial minority patients had lower 2‐year RFS (53.3% vs 93.5%, P = .001) and OS (73.7% vs 92.6%, P = .008). Race was an independent predictor for both RFS (P = .027) and OS (P = .047).ConclusionsThese results highlight the impact of social contextual factors on health. Interventions targeted at socioeconomically vulnerable populations are needed to reduce disparities in ASCC outcomes.
Small‐Molecule Stimulators of NRF1 Transcriptional Activity
Authors: Iaconelli Jonathan , Ibrahim Lara , Chen Emily , Hull Mitchell , Schultz Peter G. , Bollong Michael J. 
Published: October 2019

AbstractThe transcription factor nuclear factor erythroid 2‐related factor 1 (NRF1) maintains proteostasis and promotes cellular resilience by stimulating the transcription of proteasomal subunits and a host of protective enzymes. Although NRF1 activation would likely be beneficial in a number of disease states, information regarding its ligandability and upstream regulation are lacking. Herein we report a high‐throughput chemical screen that identified selective stimulators of NRF1‐driven transcription, including unannotated inhibitors of the ubiquitin proteasome system (UPS) as well as two non‐UPS‐targeted compounds that synergistically activate NRF1 in the context of submaximal UPS inhibition. This work introduces a suite of tool molecules to study the NRF1 transcriptional response and to uncover the druggable components governing NRF1 activity in cells.