bluuebunny/crossref_metadata_2025_split huggingface dataset:
Sequential Maximum Correntropy Kalman Filtering
Authors: Kulikova Maria V. 
Published: July 2018

AbstractThis paper explores a linear state estimation problem in non‐Gaussian setting and suggests a computationally simple estimator based on the maximum correntropy criterion Kalman filter (MCC‐KF). The first MCC‐KF method was developed in Joseph stabilized form. It requires two n × n and one m × m matrix inversions, where n is a dimension of unknown dynamic state to be estimated, and m is a dimension of available measurement vector. Therefore, the estimator becomes impractical when the system dimensions increase. Our previous work has suggested an improved MCC‐KF estimator (IMCC‐KF) and its factored‐from (square‐root) implementations that enhance the MCC‐KF estimation quality and numerical robustness against roundoff errors. However, the proposed IMCC‐KF and its square‐root implementations still require the m × m matrix inversion in each iteration step of the filter. For numerical stability and computational complexity reasons it is preferable to avoid the matrix inversion operation. In this paper, we suggest a new IMCC‐KF algorithm that is more accurate and computationally cheaper than the original MCC‐KF and previously suggested IMCC‐KF. Furthermore, compared with stable square‐root algorithms, the new method is also accurate, but less computationally expensive. The results of numerical experiments substantiate the mentioned properties of the new estimator on numerical examples.
RBFNN‐Based Identification and Compensation Mechanism for Disturbance‐Like Parametric Friction with Application to Tractor‐Trailer Vehicles
Authors: Yue Ming , Hou Xiaoqiang , Gao Junjie , Yang Lu 
Published: July 2018

AbstractThis paper develops an effective identification and compensation mechanism for the disturbance‐like parametric friction of a typical underactuated tractor‐trailer vehicle system. To begin with, a parametric friction model is proposed to describe various friction effects associated with the system velocity, and then a disturbance‐like parametric friction concept is introduced by considering the motion characteristics of tractor‐trailer vehicle. Next, the radial basis function neural network (RBFNN) is employed to identify the friction due to its high convergence rate, superior approximation precision and local‐minima avoidance ability. Afterwards, a sliding mode control (SMC) is utilized to compensate the identified friction due to its numerous merits, such as strong robustness and fast convergence. On the basis of the effective combination of identification and compensation mechanism, a favorable transient performance can be achieved during the desired velocity tracking process. Lastly, the simulation results confirm that the RBFNN‐based disturbance‐like parametric friction identification and compensation mechanism can effectively improve the trajectory tracking performance of tractor‐trailer vehicle.
When should meta‐analysis avoid making hidden normality assumptions?
Authors: Jackson Dan , White Ian R. 
Published: July 2018

AbstractMeta‐analysis is a widely used statistical technique. The simplicity of the calculations required when performing conventional meta‐analyses belies the parametric nature of the assumptions that justify them. In particular, the normal distribution is extensively, and often implicitly, assumed. Here, we review how the normal distribution is used in meta‐analysis. We discuss when the normal distribution is likely to be adequate and also when it should be avoided. We discuss alternative and more advanced methods that make less use of the normal distribution. We conclude that statistical methods that make fewer normality assumptions should be considered more often in practice. In general, statisticians and applied analysts should understand the assumptions made by their statistical analyses. They should also be able to defend these assumptions. Our hope is that this article will foster a greater appreciation of the extent to which assumptions involving the normal distribution are made in statistical methods for meta‐analysis. We also hope that this article will stimulate further discussion and methodological work.
Alka(e)ne synthesis in Cupriavidus necator boosted by the expression of endogenous and heterologous ferredoxin–ferredoxin reductase systems
Authors: Crépin Lucie , Barthe Manon , Leray Florence , Guillouet Stéphane E. 
Published: July 2018

AbstractTo boost aldehyde deformylating oxygenase (ADO) activity in a Cupriavidus necator strain expressing a synthetic alkane pathway, the expression of two ferredoxin–ferredoxin reductase systems was tested. The genes of a native fd/FNR‐like system were identified in C. necator and expressed in a previously engineered alka(e)ne producing strain. The improved production of alka(e)nes in this Re2061‐pMAB1 strain confirmed the activity of the native Fd/FNR system in C. necator. Concomitantly, the expression of the heterologous system from Synechococcus elongatus was investigated identically, leading to a second strain, Re2061‐pMAB2. In the bioreactor, the aldehyde production was strongly reduced compared with the original alka(e)ne producer, leading to alka(e)nes production up to 0.37 and 1.48 g/L (22 and 82 mg/gCDW), respectively. The alka(e)ne production yield of Re2061‐pMAB2 accounted for 15% of the theoretical yield. We report here the highest level and yield of alka(e)nes production by an engineered bacterium to date.
Contribution of cellulose synthesis, formation of fibrils and their entanglement to the self‐flocculation of Zymomonas mobilis
Authors: Xia Juan , Liu Chen‐Guang , Zhao Xin‐Qing , Xiao Yi , Xia Xiao‐Xia , Bai Feng‐Wu 
Published: July 2018

AbstractDue to the unique Entner‐Doudoroff pathway, Zymomonas mobilis has been acknowledged as a potential host to be engineered for biorefinery to produce biofuels and biobased chemicals. The self‐flocculation of
Z. mobilis can make the bacterial cells self‐immobilized within bioreactors for high density to improve product productivities, and in the meantime enhance their tolerance to stresses, particularly product inhibition and the toxicity of byproducts released during the pretreatment of lignocellulosic biomass. In this work, we explored mechanism underlying such a phenotype with the self‐flocculating strain ZM401 developed from the regular non‐flocculating strain ZM4. Cellulase de‐flocculation and the restoration of the self‐flocculating phenotype for the de‐flocculated bacterial cells subjected to culture confirmed the essential role of cellulose biosynthesis in the self‐flocculation of ZM401. Furthermore, the deactivation of both Type I and Type IV restriction‐modification systems was performed for ZM4 and ZM401 to improve their transformation efficiencies. Comparative genome analysis detected the deletion of a thymine from ZMO1082 in ZM401, leading to a frame‐shift mutation for the putative gene to be integrated into the neighboring downstream gene ZMO1083 encoding the catalytic subunit A of cellulose synthase, and consequently created a new gene to encode a larger transmembrane protein BcsA_401 for more efficient synthesis of cellulose as well as the development of cellulose fibrils and their entanglement for the self‐flocculation of the mutant. These speculations were confirmed by the morphological observation of the bacterial cells under scanning electron microscopy, the impact of the gene deletion on the self‐flocculation of ZM401, and the restoration of the self‐flocculating phenotype of ZM401
ΔbcsA by the gene complementation. The progress will lay a foundation not only for fundamental research in deciphering molecular mechanisms underlying the self‐flocculation of
Z. mobilis and stress tolerance associated with the morphological change but also for technological innovations in engineering non‐flocculating
Z. mobilis and other bacterial species with the self‐flocculating phenotype.
Isolation of cancer‐associated fibroblasts and its promotion to the progression of intrahepatic cholangiocarcinoma
Authors: Sha Meng , Jeong Seogsong , Qiu Bi‐jun , Tong Ying , Xia Lei , Xu Ning , Zhang Jian‐jun , Xia Qiang 
Published: July 2018

AbstractIntrahepatic cholangiocarcinoma is a highly fatal tumor characterized by an abundant stromal environment. Cancer‐associated fibroblasts play key roles in tumor growth and invasiveness and have been regarded as a potential therapeutic target. This study was designed to isolate human primary cancer‐associated fibroblasts of intrahepatic cholangiocarcinoma to study tumor‐stroma interactions and to analyze the clinical relevance of alpha‐smooth muscle actin ‐positive cancer‐associated fibroblasts in patients with intrahepatic cholangiocarcinoma. The isolated cancer‐associated fibroblasts were positive for alpha‐smooth actin, fibroblast‐specific protein‐1, fibroblast activation protein, and PDGFR‐β. In addition, cancer‐associated fibroblasts were found to increase proliferation, migration, and invasion of cholangiocarcinoma cells in vitro and promote tumor growth of mice in vivo. Moreover, alpha‐smooth muscle actin‐positive expression of cancer‐associated fibroblasts predicted unfavorable prognosis in patients with intrahepatic cholangiocarcinoma and showed correlation with presence of lymph node metastasis. This study may provide a useful tool to investigate further effect of cancer‐associated fibroblasts on the molecular mechanism of cholangiocarcinoma cells as well as contribution of cancer‐associated fibroblasts in lymphangiogenesis and lymph node metastasis.
Designing deployable 3D scissor structures with ball‐and‐socket joints
Authors: Chen Xuejin , Jiang Haoming , Xuan Tingting , Huang Lihan , Liu Ligang 
Published: July 2018

AbstractScissor structures, which transform from a compact state to an expanded state, are widely used in various fields, ranging from architectural design to aerospace applications. We focus on a challenging problem that breaks through the restriction of planarity: to design scissor structures that expand from one given 3D shape to another 3D shape. To achieve this purpose, we propose a three‐step algorithm to construct a 3D scissor structure that realizes non‐uniform concentration between two different 3D curves. First, the input shapes are divided into scissor segments, which are composed of a sequence of planar scissor units based on the shape correspondence. Secondly, we compute the scissor unit geometry of each segment in a suggestive manner. Finally, the ball‐and‐socket joints with parameterized guide slits are integrated in order to connect the scissor segments, thereby completing the 3D deployment. Judging from a series of simulation and fabrication results, we demonstrate that our approach generates deployable structures for a wide range of 3D shape pairs.
Recent Advances in the Development of Optical Imaging Probes for γ‐Glutamyltranspeptidase
Authors: Luo Zhiliang , An Ruibing , Ye Deju 
Published: July 2018

Abstractγ‐Glutamyltranspeptidase (GGT) is a cell‐membrane‐bound protease that participates in cellular glutathione and cysteine homeostasis, which are closely related to many physiological and pathological processes. The accurate measurement of GGT activity is useful for the early diagnosis of diseases. In the past few years, many efforts have been made to build optical imaging probes for the detection of GGT activity both in vitro and in vivo. In this Minireview, recent advances in the development of various optical imaging probes for GGT, including activatable fluorescence probes, ratiometric fluorescence probes, and activatable bioluminescence probes, are summarized. This review starts from the instruction of the GGT enzyme and its biological functions, followed by a discussion of activatable fluorescence probes that show off–on fluorescence in response to GGT. GGT‐activatable two‐photon fluorescence imaging probes with improved imaging depth and spatial resolution are also discussed. Ratiometric fluorescence probes capable of accurately reporting on GGT levels through a self‐calibration mechanism are discussed, followed by describing GGT‐activatable bioluminescence probes that can offer a high signal‐to‐background ratio to detect GGT in living mice. Finally, current challenges and further perspectives for the development of molecular imaging probes for GGT are addressed.
Sjögren's syndrome concurrent with protein‐losing gastroenteropathy with secondary systemic capillary leak syndrome : A case report
Authors: Watanabe Kei , Murakami Shinichiro , Misago Masahiro , Yoshikawa Mai , Tamai Daisuke , Nakao Shinichiro , Ueoka Takato , Ito Mototoshi , Shinomura Yasuhisa , Kajiwara Nobuyuki 
Published: July 2018

Key Clinical MessageSjögren's syndrome concurrent with protein‐losing gastroenteropathy can develop into secondary systemic capillary leak syndrome. Thus, it is important to diagnose the condition as soon as possible and simultaneously administer treatment for Sjögren's syndrome, protein‐losing gastroenteropathy, and systemic capillary leak syndrome.
Decreasing Filter Cake Resistance by Using Packing Structures
Authors: Bandelt Riess Peter M. , Engstle Jörg , Kuhn Michael , Briesen Heiko , Först Petra 
Published: July 2018

AbstractPacked beds used in absorption columns are evaluated to determine whether they can also be beneficial for cake‐forming filtrations. To assess this, model systems are characterized and separated by using a dead‐end filter cell. Filtrations are conducted with different packings; the filtrate amount over time and resulting turbidity are evaluated. Packings increase the filter cake resistance and the separation time of the cakes formed with approximately incompressible solids. However, they exhibit a positive effect on the filtration of a more complex, compressible substance; the process is not only accelerated, but also the quality of the obtained filtrate is not compromised. These results demonstrate potential in the use of packed beds for the filtration of complex biogenic suspensions.
Internal‐Edge‐Substituted Coumarin‐Fused [6]Helicenes: Asymmetric Synthesis, Structural Features, and Control of Self‐Assembly
Authors: Usui Kazuteru , Yamamoto Kosuke , Ueno Yuhei , Igawa Kazunobu , Hagihara Ryusuke , Masuda Toshinobu , Ojida Akio , Karasawa Satoru , Tomooka Katsuhiko , Hirai Go , Suemune Hiroshi 
Published: July 2018

Abstractπ‐Conjugated helicenes containing heteroatoms have attracted significant attention due to their diverse chemical and electronic structures, as well as tunable physical properties. It was rationally anticipated that the self‐assembly of coumarin‐fused helicenes would be controlled by the effects of a substituent on the internal edge of the helix. Here, this work reports the efficient syntheses of coumarin‐fused helicenes 1 a,b (R=Ph, Me), and the enantioselective synthesis of 1 a (R=Ph) by chiral AuI‐catalyzed hydroarylation. The helical structure of 1 was unambiguously determined by X‐ray crystallography. Of particular note, the enantiomerically pure crystal of 1 a adopted a one‐dimensional columnar structure based on π–π stacking interactions, as expected. Furthermore, a significant difference between the fluorescence quantum yields of the enantiomerically pure form and racemate of 1 a was observed.
Absence of electrocardiographic left ventricular hypertrophy is associated with increased mortality after transcatheter aortic valve replacement
Authors: Kampaktsis Polydoros N. , Ullal Ajayram V. , Swaminathan Rajesh V. , Minutello Robert M. , Kim Luke , Bergman Geoffrey S. , Feldman Dmitriy N. , Singh Harsimran , Wong Shing Chiu , Okin Peter M. 
Published: July 2018

BackgroundElectrocardiographic (ECG) left ventricular hypertrophy (LVH) has been associated with increased mortality in patients with asymptomatic aortic stenosis (AS) and hypertension. However, patients with symptomatic AS undergoing transcatheter aortic valve replacement (TAVR) have higher percentages of myocardial fibrosis or amyloidosis that have been associated with decreased ECG voltage and worse outcomes.HypothesisWe tested the hypothesis that baseline ECG LVH is independently associated with increased all‐cause mortality after TAVR.MethodsA total of 231 patients (96 men; mean age 84.7 ± 7.8 years) that underwent TAVR at our institution were included. Cornell voltage, defined as SV3 + RaVL, was used to assess for presence of ECG LVH using gender‐specific cut‐off values. We used the Kaplan‐Meier estimator to derive survival curves. Multivariate Cox regression analysis was used to compare mortality between patients without vs with ECG LVH and adjust for echocardiographic LVH and predictors of mortality in this cohort.ResultsOver a follow‐up time of 16.3 ± 10.4 months, the absence of ECG LVH was significantly associated with increased mortality (40.4% vs 23.6% at 2‐years, log rank P = 0.003). After adjusting for echocardiographic LVH and predictors of mortality in our cohort, the absence of ECG LVH remained a predictor of increased mortality (HR = 1.79, CI 95% 1.02‐3.14, P = 0.042).ConclusionsThe absence of ECG LVH was independently associated with increased mortality in patients undergoing TAVR. Baseline ECG may have an important prognostic role in these patients and could lead to further testing to evaluate for myocardial fibrosis or amyloidosis.
TIMI‐AF score and cardiovascular events in vitamin K antagonists‐naïve outpatients with atrial fibrillation
Authors: Pérez Cabeza Alejandro Isidoro , Bravo Marques Rafael , Chinchurreta Capote Pedro Antonio , Ruiz Mateas Francisco , Fanola Christina L. , Rosas Cervantes Gabriel , González Correa Jose Antonio , Valle Alberca Almudena , Mesa Prado Fidel , López Tejero Sergio , Ruff Christian Thomas 
Published: July 2018

BackgroundThe TIMI‐AF score predicts poor outcomes in patients with atrial fibrillation (AF) and guides selection of anticoagulant therapy by identifying clinical benefit of direct oral anticoagulants (DOACs) or vitamin K antagonists (VKA).HypothesisOur objective was to determine the ability to predict cardiovascular events according to the TIMI‐AF score in a real‐world population.MethodsRetrospective observational study of VKA‐naïve patients with AF was seen at a cardiology outpatient clinic in Spain between November 2012 and August 2014. We recorded adverse events (myocardial infarction, systemic embolism or stroke, major bleeding, and death).ResultsThe study population comprised of 426 patients (50.7% men, mean age, 69 ± 14 years). The TIMI‐AF score identified 372 patients (87.3%) with a low risk, 50 patients (11.7%) with an intermediate risk, and 4 patients (0.9%) with a high risk. After a mean follow‐up of 423.4 ± 200.1 days, 37 patients (9%) experienced an adverse event. Patients with a TIMI‐AF score ≥ 7 had a poorer cardiovascular prognosis (HR, 6.1; 95%CI, 3.2‐11.7; P < 0.001). The area under the ROC curve of TIMI‐AF was 0.755 (95%CI, 0.669‐0.840; P < 0.001), which was greater than that of CHA2DS2VASc (0.641; 95%CI, 0.559‐0.724; P = 0.004), HAS‐BLED (0.666; 95%CI, 0.578‐0.755; P < 0.001), and SAMeTT2R2 (0.529; 95%CI, 0.422‐0.636; P = 0.565). Similar results were obtained in relation to the net clinical outcome (life‐threatening bleeding, disabling stroke, or all‐cause mortality).ConclusionsThe TIMI‐AF risk score can identify patients who are at greater risk of cardiovascular events and a poor net clinical outcome with a better diagnostic yield than CHA2DS2VASc, HAS‐BLED, and SAMeTT2R2.
d‐Polyarginine Lipopeptides as Intestinal Permeation Enhancers
Authors: Garcia Josep , Fernández‐Blanco Álvaro , Teixidó Meritxell , Sánchez‐Navarro Macarena , Giralt Ernest 
Published: July 2018

AbstractAn estimated 285 million people were living with diabetes in 2010, and this number is expected to reach 440 million by 2030. Current treatment of this disease involves the intradermal injection of insulin analogues. Many alternative administration routes have been proposed, the oral route being the most widely studied. One of the most interesting approaches for insulin delivery is the use of permeation enhancers to increase its transport across the gastrointestinal tract (GIT). Cell‐penetrating peptides (CPPs) are a remarkable example of this family of compounds. Another alternative is the use of medium‐chain fatty acids (MCFAs) to temporally disrupt the tight junctions of the GIT, thereby allowing greater drug transport. A combination of both strategies can provide a synergistic way to increase drug transport through the GIT. In this study we evaluated the complexation of insulin glulisine, an insulin analogue administered subcutaneously or intravenously in clinical practice, with a well‐known CPP modified with the MCFA lauric acid. We prepared several formulations, examined their stability, and tested the best candidates in an intestinal cell‐based model. In particular, two compounds (C12‐r4 and C12‐r6) were found to significantly increase the transport of insulin, and therefore show promise as a new delivery system worthy of further evaluation.
In Situ Decoration of ZnxCd1−xS with FeP for Efficient Photocatalytic Generation of Hydrogen under Irradiation with Visible Light
Authors: Zhu Xianglin , Yu Sijia , Gong Xuezhong , Xue Can 
Published: July 2018

AbstractFeP as a noble‐metal‐free catalyst has been successfully decorated onto the ZnxCd1−xS photocatalyst surface through an in situ phosphating process. In particular, the 2 % FeP/Zn0.5Cd0.5S−P sample showed the best hydrogen generation activity of 24.45 mmol h−1 g−1 which is over 130 times higher than that of pure Zn0.5Cd0.5S and nearly 1.3 times higher than that of the 1 % Pt‐loaded Zn0.5Cd0.5S−P sample. The apparent quantum yield (AQY) of the 2 % FeP/Zn0.5Cd0.5S−P was estimated to be over 10 % at wavelengths up to 470 nm. The fluorescence spectra and electrochemical measurement results suggest that the decorated FeP not only reduces the overpotential for H2 evolution but also promotes the separation of the photogenerated charge carriers through formation of a heterojunction with Zn0.5Cd0.5S, which eventually leads to the superior activity of the FeP/Zn0.5Cd0.5S−P photocatalyst for visible‐light‐driven hydrogen generation.
Ground motion records for seismic performance assessment: To rotate or not to rotate?
Authors: Giannopoulos Dimitrios , Vamvatsikos Dimitrios 
Published: July 2018

SummaryThe response of a non‐circular structure strongly depends on the orientation of the horizontal ground motion components vis‐à‐vis the structure's principal axes. At the same time, the structural response is also a function of accelerogram characteristics that give rise to considerable record‐to‐record variability even when the incident angle is neglected. Therefore, when the structural orientation relative to the fault geometry is unknown and we have limited resources for estimating the distribution of structural response given the seismic intensity, the question arises as to whether it is preferable to use (1) few records rotated to multiple orientations, (2) many records, each at a random incident angle, or (3) some combination of the two. To this purpose, we subjected several single‐degree‐of‐freedom systems and one plan‐asymmetric multi‐degree‐of‐freedom structure to a pulsive and a non‐pulsive set of ground motions using different combinations of record set size and incident angle rotations. In all cases, the natural record‐to‐record variability of the (unrotated) waveforms clearly outweighed the influence of the record orientation. In addition, the choice of an intensity measure that utilizes the geometric mean of spectral accelerations in both horizontal axes at one or more periods of vibration was found to further enhance this difference, essentially nullifying the already small effect of the incident angle. In all cases, spending any significant proportion of the limited number of dynamic analyses to incorporate the effect of incident angle was detrimental to the fidelity of the estimated performance.