bluuebunny/crossref_metadata_2025_split huggingface dataset:
Practical and robust test for comparing binomial proportions in the randomized phase II setting
Authors: Attwood Kristopher , Park Soyun , Hutson Alan D. 
Published: October 2021

AbstractThe one‐arm, non‐randomized, one/two‐stage phase II designs have been a mainstay in oncology trials for evaluating response rates or similar variants (i.e., tests about single proportions). With the goal of screening new therapies that have the potential to move into a randomized phase III trial or a subsequent randomized phase II trial, all while maintaining a logistically feasible sample size. However, since the implementation of the Food and Drug Administration's Fast Track Designation, there has been a trend toward randomized phase II clinical trials as a source of stronger evidence for those seeking fast‐track approvals. While there are many single‐ and multi‐stage randomized designs for evaluating proportions in this phase II setting, there still exist limitations in terms of sample size (which directly impacts cost and study duration) or operating characteristics (ex. maintained type I error). In this article, we propose a new test for comparing two binomial proportions, which is a modification across existing methods (the standard z‐test and Jung's test). This approach is contrasted with existing methods via numeric evaluation and further contrasted using a real‐world oncology trial. The proposed method demonstrates improvements in efficiency and robustness against deviations from design assumptions. When applied to the existing trial, significant savings with respect to cost and time are illustrated. Our proposed test for comparing binomial proportions provides an efficient and robust alternative in the randomized phase II oncology setting, especially when the control arm has a high rate.
Comprehensive degradation profiling and influence of different oxidizing reagents on tinoridine hydrochloride: Structural characterization of its degradation products using HPLC and HRMS
Authors: Dhiman Vivek , Patil Kanchan , Velip Laximan , Talluri M. V. N. Kumar , Gananadhamu Samanthula 
Published: October 2021

RationaleStress testing on tinoridine hydrochloride was carried out using a multidimensional approach. This included different conditions: hydrolytic (acidic, alkaline, and neutral conditions), different oxidative reagents, thermal, photolytic conditions, HPLC method development, and structural elucidation using high‐resolution mass spectrometry (HRMS). It provides the basis for quality control of tinoridine hydrochloride and its derivatives during storage conditions.MethodsThe tinoridine hydrochloride was subjected to a variety of stress conditions. A gradient reversed‐phase HPLC method was developed on a X‐Bridge C18 column (250 × 4.6 mm, 5 μm) to separate all the degradation products (DPs). HRMS studies have been performed to elucidate the structure of DPs.ResultsHPLC‐PDA study revealed that significant degradation products were formed in hydrolytic, AIBN (radical initiator at 40°C), thermal, and solid‐state photolight stress conditions, but the drug was stable under oxidative conditions (H2O2, Fenton's reagent at room temperature and ferric chloride at 40°C). The structure of degradation products was elucidated, and mechanism of their formation was explained.ConclusionStress study was successfully carried out as per ICH Q1A (R2) guideline on tinoridine hydrochloride. A total of six new degradation products were characterized, DP 2 and DP 6 formed by the effect of co‐solvent. This study provides the scientifically sound basis for quality monitoring and storage conditions of tinoridine hydrochloride.
Observer‐based consensus control for multi‐agent systems with measurement noises and external disturbances
Authors: Huang Xiaolong , Chen Yangzhou , Zhan Jingyuan 
Published: October 2021

AbstractThis study presents a distributed observer‐based consensus control for general linear multi‐agent systems under measurement noises and external disturbances. By using the state linear transformation with the matrix constructed from the incidence matrix of a virtual chained directed spanning tree, we transform the observer‐based consensus problem into an asymptotic stability problem of a corresponding augmented linear system. The augmented linear system consists of the reduced‐order system deduced from dynamic equations of the agents and state estimation error system. Based on asymptotic stability of the augmented linear system, we present some sufficient conditions in terms of linear matrix inequalities for the existence of the distributed observer‐based consensus controller. Finally, the effectiveness of the proposed approach is illustrated by a numerical example.
EIL‐SLAM: Depth‐enhanced edge‐based infrared‐LiDAR SLAM
Authors: Chen Wenqiang , Wang Yu , Chen Haoyao , Liu Yunhui 
Published: October 2021

AbstractTraditional simultaneous localization and mapping (SLAM) approaches that utilize visible cameras or light detection and rangings (LiDARs) frequently fail in dusty, low‐textured, or completely dark environments. To address this problem, this study proposes a novel approach by tightly coupling perception data from a thermal infrared camera and a LiDAR based on the advantages of the former. However, applying a thermal infrared camera directly to existing SLAM frameworks is difficult because of the sensor differences. Thus, a new infrared‐visual odometry method is developed by utilizing edge points as features to ensure the robustness of the state estimation. Furthermore, an edge‐based infrared‐LiDAR SLAM framework is developed to generate a dense depth map for recovering visual scale and to provide real‐time pose estimation at the same time throughout the day. An infrared‐visual and LiDAR‐integrated place recognition method is also introduced to achieve robust loop closure. Finally, several experiments are performed to illustrate the effectiveness of the proposed approach.
Atmospheric absorption and scattering impact on optical satellite‐ground links
Authors: Giggenbach Dirk , Shrestha Amita 
Published: October 2021

SummaryFree‐space radio‐frequency (RF) communication links for intersatellite or satellite‐to‐ground communications are getting increasingly constraint by the insufficient spectrum availability and limited data rate of RF technology. With the advent of large satellite mega‐constellation networks for global communications coverage, this limitation of classical RF communication becomes even more critical. Therefore, the establishment of point‐to‐point free‐space optical link technology (FSO) in space will become of paramount importance in future systems, where the application will be for data‐relays links, or for mega‐constellations inter‐satellite links, as well as for direct data downlinks, or from deep‐space probes to ground. Further advantages of optical FSO—besides spectrum availability—is its increased power efficiency, higher data rates, avoidance of interference, and inherent protection against interception. When, however, these optical communication links have to pass through Earth's atmosphere, attenuation and scattering effects do influence the signal transmission. In this publication, we investigate the effects of atmospheric attenuation, including the effects of molecular absorption as well as aerosol scattering and absorption, for typical wavelength regions used for FSO, dependent on the link geometries. Based on transmission‐simulation databases, we show useful spectral ranges and their specific attenuation strength. Free spectral transmission windows dependent on atmospheric quality and elevation angle are identified for reliable and efficient use of the optical transmission technology in space applications.
Robust approach for variable selection with high dimensional longitudinal data analysis
Authors: Fu Liya , Li Jiaqi , Wang You‐Gan 
Published: October 2021

AbstractThis article proposes a new robust smooth‐threshold estimating equation to select important variables and automatically estimate parameters for high dimensional longitudinal data. A novel working correlation matrix is proposed to capture correlations within the same subject. The proposed procedure works well when the number of covariates increases as the number of subjects n increases. The proposed estimates are competitive with the estimates obtained with the true correlation structure, especially when the data are contaminated. Moreover, the proposed method is robust against outliers in the response variables and/or covariates. Furthermore, the oracle properties for robust smooth‐threshold estimating equations under “large n, diverging ” are established under some regularity conditions. Extensive simulation studies and a yeast cell cycle data are used to evaluate the performance of the proposed method, and results show that the proposed method is competitive with existing robust variable selection procedures.
Ring Opening of Epoxides and Aziridines with Benzotriazoles Using Magnetically Retrievable Graphene Based (CoFe@rGO) Nanohybrid
Authors: Sheoran Ankush , Kaur Jaspreet , Agarwal Jyoti , Singhal Sonal 
Published: October 2021

AbstractReduced Graphene oxide (rGO) behaves as an excellent heterogeneous catalyst because of its remarkable characteristics such as large specific surface area and high thermal stability. In this regard, Graphene oxide was converted to magnetic nanohybrid (CoFe@rGO) and utilized as an efficient heterogeneous catalyst for the ring opening reactions and act as Lewis acid to promote the reaction. Developed a new facile, environmentally benign and green methodology for the synthesis of β‐hydroxytriazoles and β‐N‐tosylsulfonamidetriazoles derivatives via ring opening reaction of epoxides and aziridines respectively in the presence of CoFe@rGO nanohybrid as catalyst in good to excellent yields under solvent free reaction conditions. Catalyst was separated from the reaction mixture by an external magnet, recycled and reused up to six catalytic runs without significant loss of catalytic activity. Environmentally benign conditions, cheap starting materials, shorter reaction times, easy work‐up and purification of the products, high regioselectivity, high yields, recyclability and reusability of catalyst are the main advantages of our protocol.
A Proton‐Transfer Complex Containing 5‐Hydroxy‐isophthalic Acid with 3,3′‐(Piperazine‐1,4‐diylbis (methylene)) Dibenzonitrile: Structural Topology, Hirshfeld Analysis, NLO, and DFT Studies
Authors: Muslim Mohd , Kamaal Saima , Mehkoom Mohd , Jane Alam Mohammad , Afzal S. M. , Ahmad Musheer 
Published: October 2021

AbstractThis work focuses on the study of a proton‐transfer complex (1) of 5‐hydroxy‐isophthalic acid (HIPA) and 3,3′‐(piperazine‐1,4‐diylbis(methylene)) dibenzonitrile (PBN). The single‐crystal XRD reveals that the HIPA and PBN molecules in complex (1) are mutually connected through intricate N+−H−O− H‐bonding interactions. Herein, close and open aperture measurement for the third‐order nonlinear optical response of the complex (1) has been investigated using the Z‐scan technique which shows its potential application in optoelectronic and photonic devices. Further, DFT calculations have been done for the HOMO‐LUMO energy gap and Mulliken atomic charge analysis which helps us to understand the proton‐transfer mechanism in the complex (1). The topological and Hirshfeld surface analysis were also achieved to understand the importance of non‐covalent interactions in the stability of the supramolecular structure and NLO properties.
Thymosin‐β4, and Human Vitronectin peptides Grafted to Collagen Tune Adhesion or VEGF Gene Expression in Human Cell Lines**
Authors: Guizzardi Roberto , Zamuner Annj , Brun Paola , Dettin Monica , Natalello Antonino , Cipolla Laura 
Published: October 2021

AbstractIn order to improve collagen bioactivity for regenerative medicine approaches, thymosin‐β4 (Tβ4P) and Human Vitronectin (HVP) derived peptides are grafted to collagen by thiol‐ene Michael addition. Tβ4P and HVP are known to exert a pro‐angiogenic and a pro‐adhesive activity respectively and HVP is involved in osteogenesis promotion. The ability of these peptides to increase collagen cell adhesion and angiogenesis properties is assessed on human cell lines. In particular, HVP‐grafted collagen increased human osteoblast adhesion and cell proliferation: after 24 h, both adhesion and proliferation roughly showed a 4‐fold increase, if compared to pristine collagen. Tβ4P‐grafted collagen promotes Vascular Endothelial Growth Factor (VEGF) gene expression in human vascular cell lines by more than 7 times. These results suggest that HVP‐grafted collagen may be an interesting biomaterial for bone tissue regeneration, while Tβ4P‐grafted collagen is useful for angiogenesis promotion.
Perceived control and reactivity to acute stressors: Variations by age, race and facets of control
Authors: Wen Jin H. , Sin Nancy L. 
Published: October 2021

AbstractGreater perceived control is associated with better health and well‐being outcomes, possibly through more adaptive stress processes. Yet little research has examined whether facets of perceived control (personal mastery and perceived constraints) predict psychological and physiological stress reactivity. The present study evaluated the associations of personal mastery and perceived constraints with changes in subjective stress and cortisol in response to acute laboratory stressors, with age and race as potential moderators. In the Midlife in the United States Refresher Study (N = 633 adults aged 25–75), participants completed a baseline perceived control measure and were subsequently recruited to participate in the laboratory stress protocol. The protocol consisted of completing two mental stress tasks (mental arithmetic and Stroop) as well as providing saliva samples and subjective stress ratings. Race moderated the association between perceived constraints and subjective stress reactivity, such that higher constraints predicted greater subjective stress responses in White participants, but no association was observed in Black participants. Higher personal mastery and perceived constraints each predicted greater increases in cortisol in response to the stress tasks (AUCi) among younger but not older adults. These findings suggest that older adults were buffered against the association between facets of control and cortisol stress reactivity. Discussion on potential racial differences in the link between constraints and stress reactivity are elaborated further, as well as considerations for future work to distinguish between facets of control and examine age and racial differences.
Highly Self‐Healable Write‐Once‐Read‐Many‐Times Devices Based on Polyvinylalcohol‐Imidazole Modified Graphene Nanocomposites
Authors: An Haoqun , Kim Youngjin , Li Mingjun , Kim Tae Whan 
Published: October 2021

AbstractRepetitious mechanical stress or external mechanical impact can damage wearable electronic devices, leading to serious degradations in their electrical performances, which limits their applications. Because self‐healing would be an excellent solution to the above‐mentioned issue, this paper presents a self‐healable memory device based on a novel nanocomposite layer consisting of a polyvinyl alcohol matrix and imidazole‐modified graphene quantum dots. The device exhibits reliable electrical performance over 600 cycles, and the electrical properties of the device are maintained without any failure under this bending stress. Further, it is confirmed that the damaged device can recover its original electric characteristics after the self‐healing process. It is believed that such outstanding results will lead the way to the realization of future wearable electronic systems.
Ultrafast, Non‐Equilibrium and Transient Heating and Sintering of Nanocrystals for Nanoscale Metal Printing
Authors: Podder Chinmoy , Gong Xiangtao , Pan Heng 
Published: October 2021

AbstractThe carrier excitation, relaxation, energy transport, and conversion processes during light‐nanocrystal (NC) interactions have been intensively investigated for applications in optoelectronics, photocatalysis, and photovoltaics. However, there are limited studies on the non‐equilibrium heating under relatively high laser excitation that leads to NCs sintering. Here, the authors use femtosecond laser two‐pulse correlation and in‐situ optical transmission probing to investigate the non‐equilibrium heating of NCs and transient sintering dynamics. First, a two‐pulse correlation study reveals that the sintering rate strongly increases when the two heating laser pulses are temporally separated by <10 ps. Second, the sintering rate is found to increase nonlinearly with laser fluence when heating with ≈700 fs laser pulses. By three‐temperature modeling, the NC sintering mechanism mediated by electron induced ligand transformation is suggested. The ultrafast and non‐equilibrium process facilitates sintering in dry (spin‐coated) and wet (solvent suspended) environments. The nonlinear dependence of sintering rate on laser fluence is exploited to print sub‐diffraction‐limited features in NC suspension. The smallest feature printed is ≈200 nm, which is ≈¼ of the laser wavelength. These findings provide a new perspective toward nanomanufacturing development based on probing and engineering ultrafast transport phenomena in functional NCs.
Determining the Structure and In Vitro Antioxidant Activity of Sulfated Polysaccharides from Cardamine hupingshanensis
Authors: Zhang Zimu , Huang Xiufang , Li Shichan , Luo Kai 
Published: October 2021

AbstractPlant and fungal polysaccharides have been extensively studied for their anticoagulant, antioxidant, antitumor, immunomodulatory, and hypoglycemic activities. Furthermore, the inherent bioactivities of various polysaccharides can be improved by appropriate chemical modifications that can confer novel properties. Particularly, Cardamine hupingshanensis polysaccharides (CHPs) have been reported to exhibit curative action against diabetes in a mouse model. Therefore, in this study, CHPs are extracted by the hot water extraction method and modified by sulfation using the sulfur trioxide‐pyridine method. Anion‐exchange chromatography is performed to obtain pure, sulfated CHPs (SCHP‐II). Nuclear magnetic resonance imaging and high‐performance liquid chromatography are performed to determine the structure and composition of SCHP‐II, respectively. The molecular weight of SCHP‐II is determined to be 22.2 kDa. A n in vitro antioxidation activity assay performed using 2,2‐azino‐bis‐3‐ethylbenzthiazoline‐6‐sulfonic acid showed that SCHP‐II exhibited better free radical‐scavenging ability than CHPs. Therefore, it is concluded that SCHP‐II can be used as an antioxidant in food and medicinal products.
Corroded Tension Chord Model: Load‐deformation behavior of structures with locally corroded reinforcement
Authors: Haefliger Severin , Kaufmann Walter 
Published: October 2021

AbstractLocalised corrosion may considerably impair the load‐bearing and deformation capacity of reinforced concrete structures. The Corroded Tension Chord Model allows investigating the related effects. The model combines the effects of tension stiffening and strain localisation due to a local cross‐section loss to calculate the load‐deformation behaviour of tension members and entire structural elements containing locally corroded reinforcing bars on a sound mechanical basis. Based on simple equilibrium considerations, the critical loss of cross‐sectional area is introduced, beyond which most of a reinforcing bar's ductility or a structure's deformation capacity, respectively, is lost. For conventional European reinforcing steel, even small cross‐section losses may be sufficient to impair ductility drastically. Illustrative calculations on structural elements with various spatial corrosion distributions but identical mean cross‐section loss reveal that the load‐deformation behaviour strongly depends on the specific corrosion parameters: Structures with few heavily corroded reinforcing bars seem to be less critical regarding strength and deformation capacity than structures with many slightly corroded reinforcing bars.
Automated finite element modeling and analysis of cracked reinforced concrete beams from three dimensional point cloud
Authors: Yu Ke , Zhang Congguang , Shooshtarian Mohammed , Zhao Weijian , Shu Jiangpeng 
Published: October 2021

AbstractModeling and assessing the load‐carrying capacity of reinforced concrete (RC) structures that are cracked is important because the condition of an RC structure changes due to natural aging and accumulated damage. The current approach to determining the residual capacity of a cracked RC structure is time‐consuming and error‐prone due to a limited capacity to obtain and process structural information. In this study, an automated approach was proposed to determining residual capacity by performing finite element (FE) analysis of an RC structure using point cloud three dimensional modeling. Two simply supported RC beams were subjected to bending tests to provide validation data. The initial activity was to extract dimensional data from laser‐scanned point cloud data of a beam. The information obtained was used to automatically generate nonlinear FE models of the beam that was used for nonlinear FE analyses in Abaqus. An initial crack was added to the beam to model a cracked beam in real conditions. Three different models were used to simulate initial cracks, a weakened element model, a cohesive zone model, and an extended FE model. The results indicate that the proposed method of automating the combination of point cloud data with nonlinear FE analysis provides a novel practical approach to modeling and assessing cracked RC beams.
Reported Catalytic Hydrofunctionalizations that Proceed in the Absence of Catalysts: The Importance of Control Experiments
Authors: Sau Sudip , Pramanik Milan , Bal Ankita , Mal Prasenjit 
Published: October 2021

AbstractThe enlarged landscape of catalysis lies in the heart of chemistry. As the journey has set a milestone in organic synthesis, its darker side has not entered into the limelight. Studies disclose that the reported reactions by using catalysts were also attainable in the absence of catalysts in many cases. This article presents a literature collection that includes the significance of control experiments in hydrofunctionalization reactions. Systematic analysis reveals that the catalysts are ambiguous and might be unessential in chemical reactions enlisted here.
Construction of Carbon‐Fluorine Bonds via Copper‐Catalyzed/‐Mediated Fluorination Reactions
Authors: Dong Tao , Tsui Gavin Chit 
Published: October 2021

AbstractThe construction of carbon‐fluorine bonds is an important yet challenging task in organic synthesis. Transition metal‐catalyzed/‐mediated C−F bond forming processes have recently emerged as a viable strategy and provided access to value‐added monofluorinated compounds. A dramatic increase in fluorination methods using inexpensive and earth‐abundant copper can be seen in the past decade surpassing those using palladium and silver. This review discusses the recent development of Cu‐catalyzed/‐mediated formation of C(sp2)−F and C(sp3)−F bonds.