bluuebunny/crossref_metadata_2025 huggingface dataset:
Florida Obsessive‐Compulsive Inventory and Children's Florida Obsessive Compulsive Inventory: A reliability generalization meta‐analysis
Authors: Sandoval‐Lentisco Alejandro , López‐Nicolás Rubén , López‐López José Antonio , Sánchez‐Meca Julio
Published: July 2022

Background

The Florida Obsessive Compulsive Inventory (FOCI) and its pediatric version, the Children's Florida Obsessive Compulsive Inventory (C‐FOCI), are instruments for evaluating obsessive‐compulsive symptomatology.

Method

A reliability generalization meta‐analysis was conducted to estimate an average reliability of the scores and to identify study characteristics that explained the heterogeneity among scores. Using Kuder–Richardson 20 (KR‐20) and Cronbach's α, a total of 23 and 20 independent samples were included in the meta‐analysis for the FOCI and C‐FOCI.

Results

We found an average KR‐20 of 0.826 for the FOCI's Symptom Checklist and an α of 0.882 FOCI's Symptom Severity. An average KR‐20 of 0.740 was found for the C‐FOCI's Symptom Checklist, while an average α of 0.794 was found for the C‐FOCI's Symptom Severity. Moderator analyses showed that the source of the coefficients (i.e., whether they were reported by the authors of the primary study or estimated by the meta‐analysts) was an important variable for the FOCI Symptom Severity, and that the focus of the study (i.e., whether it was psychometric or applied) and the sample size were relevant for the C‐FOCI Symptom Checklist.

Conclusions

Considering that the FOCI and C‐FOCI are scales characterized by their brevity and ease of use, and the reliabilities obtained here, both scales are well suited for screening purposes.
Supereulerian regular matroids without small cocircuits
Authors: Huo Bofeng , Du Qingsong , Li Ping , Wu Yang , Yin Jun , Lai Hong‐Jian
Published: July 2022

A cycle of a matroid is a disjoint union of circuits. A matroid is supereulerian if it contains a spanning cycle. To answer an open problem of Bauer in 1985, Catlin proved in [J. Graph Theory 12 (1988) 29–44] that for sufficiently large , every 2‐edge‐connected simple graph with and minimum degree is supereulerian. In [Eur. J. Combinatorics, 33 (2012), 1765–1776], it is shown that for any connected simple regular matroid , if every cocircuit of satisfies , then is supereulerian. We prove the following. (i) Let be a connected simple regular matroid. If every cocircuit of satisfies , then is supereulerian. (ii) For any real number with , there exists an integer such that if every cocircuit of a connected simple cographic matroid satisfies , then is supereulerian.
Hidden behind the model minority stereotype: Exploring disparities and the role of parent empowerment in Asian students’ college enrollment
Authors: Kim Jungnam , Bryan Julia Green , Griffin Dana , Sharma Gitima
Published: July 2022

We investigated the relationship between Asian parent empowerment and their children's college enrollment in a sample of 357 Asian parents from various ethnic subgroups using the High School Longitudinal Study 2009. A multinomial logistic regression indicated differences in Asian students’ college enrollment by ethnic subgroup and income and in the role of personal and community parent empowerment in college enrollment. The results indicate the danger of the model minority myth in masking disparities among Asian students.
Applications of Telemedicine in Speech‐Language Pathology: Evaluation of Patient Satisfaction
Authors: Little Christine C. , Russell Stephen , Hwang Chaewon , Goldberg Leanne , Brown Sarah , Kirke Diana , Courey Mark
Published: July 2022

Objectives

The study aimed to evaluate patient satisfaction with speech‐language therapy televisits and to identify factors influencing the level of satisfaction.

Methods

Participants were recruited from an academic tertiary voice and swallowing center who had completed ≥1 telehealth session of speech‐language therapy with a speech‐language pathologist between March, 2020 and April, 2021. Patient satisfaction was assessed using the Short Assessment of Patient Satisfaction (SAPS), a validated 7‐item survey. Demographic characteristics of participants were collected from a review of patient charts.

Results

65/239 patients completed the SAPS survey, representing a response rate of 27%. The average age of study participants was 54.92 ± 16.45 years, with 49.2% identifying as female, 33.9% as male, and 16.9% as trans‐female. The mean SAPS score was 22.60 ± 3.89, with 84.62% of patients satisfied or very satisfied with their visit. Patients were most satisfied with provider respect (3.91 ± 0.34) and care received (3.74 ± 0.64), and least satisfied with visit length (2.32 ± 1.38) and explanation of treatment results (2.62 ± 1.72). Patient satisfaction was positively correlated with younger age and an increased number of televisits. Satisfaction did not differ significantly by gender identity, type of therapy received, insurance type, travel distance, or prior in‐person therapy.

Conclusion

Clinicians are able to achieve high patient satisfaction with speech‐language therapy when delivered by telehealth. Patient satisfaction remained high across diverse patient populations and range of clinical needs. Clinicians should remain cognizant of the unique limitations of older patients when conducting telehealth visits.

Lay Summary

Clinicians are able to achieve high patient satisfaction with speech‐language therapy when delivered via telehealth. Satisfaction remained high regardless of gender identity, type of therapy received, type of insurance, travel distance, or completion of prior in‐person therapy.

Level of Evidence

4 Laryngoscope, 133:895–900, 2023
A theory for the relationship between lake surface area and maximum depth
Authors: Cael B. B. , Seekell David
Published: July 2022

Maximum depth is crucial for many lake processes and biota, but attempts to explain its variation have achieved little predictive power. In this paper, we describe the probability distribution of maximum depths based on recent developments in the theory of fractal Brownian motions. The theoretical distribution is right‐tailed and adequately captures variations in maximum depth in a dataset of 8164 lakes (maximum depths 0.1–135 m) from the northeastern United States. Maximum depth increases with surface area, but with substantial random variation—the 95% prediction interval spans more than an order of magnitude for lakes with any specific surface area. Our results explain the observed variability in lake maximum depths, capture the link between topographic characteristics and lake bathymetry, and provide a means to upscale maximum depth‐dependent processes, which we illustrate by upscaling the diffusive flux of methane from northern lakes to the atmosphere.
ISO2‐PU Honeycomb Porous Films with a Peculiar Crystalline Structure by the Breath Figure Method Promote Osteogenic Differentiation of Stem Cells
Authors: Yang Wei , Hong Yawen , Chen Yimei , Wang Yuanliang , Luo Yanfeng
Published: July 2022

The breath figure (BF) method is a handy strategy to prepare porous films. Linear shape memory polyurethanes (SMPUs) are among the most promising polymers for bone repair or regeneration. However, little attention has been paid to the fabrication of SMPU films by using the BF method. In this work, an amorphous SMPU containing isosorbide (ISO) in the long‐chain hard segments (ISO2‐PU) is fabricated into honeycomb porous films. Strikingly, a peculiar crystalline structure with a “Z” configuration and highly regional orientation is formed on the hexagonal holes of the porous films, which results in significantly enhanced mechanical properties. Moreover, the ISO2‐PU honeycomb porous films can markedly accelerate the osteogenic differentiation of rat mesenchymal stem cells, indicating that the porous films have great potentials as bone repair materials. It is further speculated that the Marangoni effect in the condensed water droplets and the molecular assembly of ISO2‐PU due to the strong hydrogen bonds and the chiral center effect of ISO are key contributors. This work, to the best of authors’ knowledge, is the first time that this special crystalline structure on BF‐based porous films is observed and also the first speculation that combines Marangoni effect with the microstructure of BF‐based porous films.
The transglutaminase 2 cancer cell survival factor maintains mTOR activity to drive an aggressive cancer phenotype
Authors: Chen Xi , Adhikary Gautam , Newland John J. , Xu Wen , Ma Emily , Naselsky Warren , Eckert Richard L.
Published: July 2022

Transglutaminase 2 (TG2) is an important cancer stem‐like cell survival protein that is highly expressed in epidermal squamous cell carcinoma and drives an aggressive cancer phenotype. In the present study, we show that TG2 knockdown or inactivation results in a reduction in mammalian target of rapamycin (mTOR) level and activity in epidermal cancer stem‐like cells which are associated with reduced spheroid formation, invasion, and migration, and reduced cancer stem cell and epithelial–mesenchymal transition (EMT) marker expression. Similar changes were observed in both cultured cells and tumors. mTOR knockdown or treatment with rapamycin phenocopies the reduction in spheroid formation, invasion, and migration, and cancer stem cell and EMT marker expression. Moreover, mTOR appears to be a necessary mediator of TG2 action, as a forced expression of constitutively active mTOR in TG2 knockdown cells partially restores the aggressive cancer phenotype and cancer stem cell and EMT marker expression. Tumor studies show that rapamycin reduces tumor growth and cancer stem cell marker expression and EMT. These studies suggest that TG2 stimulates mTOR activity to stimulate cancer cell stemness and EMT and drive aggressive tumor growth.
The dependence on fractional orders of mild solutions to the fractional diffusion equation with memory
Authors: Akdemir Ahmet Ocak , Binh Ho Duy , O'Regan Donal , Nguyen Anh Tuan
Published: July 2022

In this paper we investigate the Cauchy problem for a fractional diffusion equation and the time‐fractional derivative is taken in the Caputo type sense. We give a representation of solutions under Fourier series and analyze initial value problems for the semi‐linear fractional diffusion equation with a memory term. We also discuss the stability of the fractional derivative order for the time under some assumptions on the input data. Our key idea is to use Mittag‐Leffler functions, the Banach fixed point theorem, and some Sobolev embeddings.
A note on contributions concerning nonseparable spaces with respect to signal processing within Bayesian frameworks
Authors: Samko Natasha , Singh Harpal
Published: July 2022

In this paper, we discuss the study of some signal processing problems within Bayesian frameworks and semigroups theory, in the case where the Banach space under consideration may be nonseparable. For applications, the suggested approach may be of interest in situations where approximation in the norm of the space is not possible. We describe the idea for the case of the abstract Cauchy problem for the evolution equation and provide more detailed example of the diffusion equation with the initial data in the nonseparable Morrey space.
Magnetic field strength dependent SNR gain at the center of a spherical phantom and up to 11.7T
Authors: Le Ster Caroline , Grant Andrea , Van de Moortele Pierre‐François , Monreal‐Madrigal Alejandro , Adriany Gregor , Vignaud Alexandre , Mauconduit Franck , Rabrait‐Lerman Cécile , Poser Benedikt A. , Uğurbil Kâmil , Boulant Nicolas
Published: July 2022

Purpose

The SNR at the center of a spherical phantom of known electrical properties was measured in quasi‐identical experimental conditions as a function of magnetic field strength between 3 T and 11.7 T.

Methods

The SNR was measured at the center of a spherical water saline phantom with a gradient‐recalled echo sequence. Measurements were performed at NeuroSpin at 3, 7, and 11.7 T. The phantom was then shipped to Maastricht University and then to the University of Minnesota for additional data points at 7, 9.4, and 10.5 T. Experiments were carried out with the exact same type of birdcage volume coil (except at 3 T, where a similar coil was used) to attempt at isolating the evolution of SNR with field strength alone. Phantom electrical properties were characterized over the corresponding frequency range.

Results

Electrical properties were found to barely vary over the frequency range. Removing the influence of the flip‐angle excitation inhomogeneity was crucial, as expected. After such correction, measurements revealed a gain of SNR growing as B01.94 ± 0.16 compared with B02.13 according to ultimate intrinsic SNR theory.

Conclusions

By using quasi‐identical experimental setups (RF volume coil, phantom, electrical properties, and protocol), this work reports experimental data between 3 T and 11.7 T, enabling the comparison with SNR theories in which conductivity and permittivity can be assumed to be constant with respect to field strength. According to ultimate SNR theory, these results can be reasonably extrapolated to the performance of receive arrays with greater than about 32 elements for central SNR in the same spherical phantom.
Display Week 2022 Highlights
Authors:   Editorial Staff
Published: July 2022

After a pandemic‐related two‐year hiatus, many enjoyed the in‐person Display Week conference. Attendees had an opportunity to hear powerful keynote speakers, cutting‐edge informative technical content, and view a new generation of electronic displays.
Parametric research on the time step and spring stiffness in three‐dimensional discontinuous deformation analysis method
Authors: Fan Hongyun , Li Liping , Liu Hongliang , Ni Jian , Cheng Shuai , Zhou Hao
Published: July 2022

Three‐dimensional discontinuous deformation analysis method (3D.DDA) is a dynamic calculation method based on the implicit solution. Inertial force is introduced in the solution process to ensure that the time variable is the real time variable, and springs are applied at the block boundary to avoid mutual intrusion between blocks. Therefore, the value of time step and contact spring stiffness directly affect the accuracy of 3D.DDA calculation results. Firstly, we analyzed the effects of the time step and contact spring stiffness on the numerical calculation results of the 3D.DDA method based on the theoretical formula derivation. Secondly, we studied the influence mechanism of time step on the simulation results of the 3D.DDA method individually based on the double block free falling model. And we determined the reasonable value area of time step. Then, considering the contacts between blocks, we studied the joint influence mechanism of time step and contact spring stiffness on the 3D.DDA simulation results based on the double block sliding model. And we analyzed the error between the 3D.DDA simulation value and the theoretical value under the conditions of different time step and contact spring stiffness. Based on that, we divided the combined value area of time step and contact spring stiffness into four regions (Q1, Q2, Q3, and Q4) and determined the optimal value area of time step and contact spring stiffness. At last, we carried out the slope rockfall model experiment and numerical simulation, and the trajectory of the falling rock in the numerical simulation was basically consistent with the experiment results, which verified the effectiveness of the optimal value area of time step and contact spring stiffness. The research results can provide a reference for the choice of the value of time step and contact spring stiffness in the numerical simulation based on the 3D.DDA method.
A length scale insensitive phase‐field model for fully coupled thermo‐mechanical fracture in concrete at high temperatures
Authors: Wu Jian‐Ying , Chen Wan‐Xin , Zhou Hao
Published: July 2022

Fracture in concrete at high temperatures involves complex thermo‐mechanical couplings and arbitrary crack evolution, imposing great challenges to its computational modeling. This work addresses a length scale insensitive phase‐field cohesive model for fully coupled thermo‐mechanical fracture in concrete at high temperatures. Both the thermal expansion and transient creep strain are accounted for in the kinematics. Based on the underlying phase‐field cohesive model for fracture in solids at ambient temperature, the temperature‐dependent mechanical properties of concrete, that is, Young's modulus, tensile and compressive strengths and fracture energy, and so forth, are all incorporated. In addition to the cracking‐induced mechanical damage mechanism represented by the crack phase‐field, the thermal deterioration mechanism is also considered by a temperature‐dependent thermal damage variable. The numerical implementation of the proposed model into the multi‐field finite element method is then briefly addressed. Several representative numerical examples, for example, thermally induced cracking in energy storage structures, thermal shock in quenched concrete plates, mode‐I and mixed‐mode failure of notched beams at high temperatures, and so forth, are presented for the validation. The effects of various expressions for the transient creep strain (TCS) on the global behavior of concrete structures are also studied. As in those purely mechanical problems, both the predicted crack pattern and global responses for all examples are insensitive to the incorporated phase‐field length scale. Being able to capture the fully coupled thermo‐mechanical fracture in concrete, the proposed phase‐field cohesive model, combined with a reliable hydro‐chemo‐thermal analysis, is promising in assessing the integrity and safety of concrete structures at high temperatures like fire scenarios.
High‐density polyethylene/zinc oxide nanocomposite with antibacterial and anti‐UV radiation properties to reduce evaporation from free surface waters
Authors: Najafi Niloufar , Abedi Koupai Jahangir , Karevan Mehdi , Mostajeran Mohsen
Published: July 2022

Climate change, through rising temperatures, higher evaporation rates, and changes in rainfall, can significantly affect the availability of water resources. Evaporation losses from open‐air reservoirs can exacerbate the problem of water scarcity, making it difficult to conserve water. Accordingly, this research aimed to develop nano‐reinforced floating covers to reduce evaporation from free water surfaces. For this purpose, high‐density polyethylene (HDPE), and zinc oxide (ZnO) nanoparticles, via melt‐blending procedures, were used to fabricate the nanocomposites. The morphological, mechanical, antibacterial, and photo‐degradation responses of HDPE/ZnO nanocomposites were assessed, and the physicochemical parameters of water samples were also examined to ensure that nanocomposites did not negatively affect water quality. The results indicated that adding 1 wt% nanofiller increased the tensile strength, while flexural strength values were modestly improved by increasing nanofillers up to 10 wt%. The irradiated nanocomposites generally displayed significant enhancement not only in the tensile strength but also in the flexural strength. Meanwhile, the addition of ZnO to HDPE had no adverse effects on water quality, though contributing to the antibacterial performance of the specimens over the neat polymer. To conclude, the fabricated nanocomposite with 1 wt% ZnO could be proposed as a promising candidate to reduce evaporation losses from free water surfaces, especially in arid and semi‐arid areas.
A review on self‐healing polymers and polymer composites for structural applications
Authors: Cioffi M. Odila H. , Bomfim Anne S. C. , Ambrogi Veronica , Advani Suresh G.
Published: July 2022

Polymer composites when employed for structural applications undergo dynamic stresses and strains that initiate fatigue‐induced microcracks, which by their coalescence cause the failure of the materials, thus limiting their service life. To overcome this hurdle, one of the recent approaches relies on the development of smart self‐healing polymers that, analogously to biological systems, can use damage as a trigger to activate the self‐repair phenomenon, thus extending their service life. This work reviews the self‐healing approach in polymer‐based materials for structural applications. It focuses on three main aspects, which are also explained with schematics that illustrate the mechanisms involved. The first aspect describes the different strategies adopted for self‐healing polymeric structures, the self‐healing agents used, as well as the reactions responsible for repairing the damage. The second part is focused on the methods used to disperse the self‐healing agents and catalysts within the polymer systems. The third section details the different self‐healing mechanisms and the effectiveness of self‐healing approaches in terms of mechanical and dynamical‐mechanical behavior of materials. Challenges and future research outlook highlighting the importance of relaxation time and fatigue characterization and to understand the mechanisms and possible improvements are also presented.
Development of single nucleotide polymorphism markers and genetic diversity in guava (Psidium guajava L.)
Authors: Diaz‐Garcia Luis , Padilla‐Ramírez José S.
Published: July 2022

Societal impact statement

There are many understudied fruits of great economic and productive importance for regional agricultural hubs. Guava is an American fruit species with attractive nutritional and adaptability characteristics. However, in many countries like Mexico, its cultivation is still limited to small‐to‐medium size plantings and home gardens and depends on poorly controlled germplasm that diminishes productivity and expansion. Our study provides valuable insight to better understand guava diversity and generate high‐yielding, high‐quality, and better adapted materials. Supporting the study and development of understudied crops will provide us with more resources for facing climate change adversities and for diversifying cropping systems.

Guava (Psidium guajava L.) is a fruit crop species native to tropical and subtropical regions of America with great productive and economic potential due to its extensive environmental adaptability, nutritional value, and medicinal properties. However, the lack of molecular resources for accelerated breeding, limited knowledge about its evolutionary and domestication history, and unfavorable policies have limited its genetic improvement and broader adoption as a commercial fruit crop.

Here, we present the first diversity study in guava employing genome‐wide single nucleotide polymorphisms (SNPs). Forty‐eight accessions collected from Mexico and other continents were examined with more than 6000 high‐quality SNP markers, which represents a marker density increase of ~30x compared with previous studies. Relationships between genetic groupings and geographic origins were not apparent in this diverse guava collection using principal component and structure analyses.

Extensive germplasm exchange among guava‐producing regions and limited varietal control at commercial plantations might have contributed to ambiguities when defining the true origin and identities of existing germplasm materials. However, an analysis of domestication syndrome traits (fruit size and sugar) by wild or improved germplasm revealed several putative genomic regions under selection.

Knowledge about germplasm origins and genetic relatedness, in conjunction with reliable molecular resources and better agronomic practices, is necessary to support breeding efforts and facilitate broader adoption of orphan crops such as guava, which have increasingly important roles in light of climate change adversities and in diversifying diets and food systems.
Improvement of tissue‐specific distribution and biotransformation potential of nicotinamide mononucleotide in combination with ginsenosides or resveratrol
Authors: Bai Long‐Bo , Yau Lee‐Fong , Tong Tian‐Tian , Chan Wai‐Him , Zhang Wei , Jiang Zhi‐Hong
Published: July 2022

Decreased Nicotinamide adenine dinucleotide (NAD+) level has received increasing attention in recent years since it plays a critical role in many diseases and aging. Although some research has proved that supplementing nicotinamide mononucleotide (NMN) could improve the level of NAD+, it is still uncertain whether the NAD+ level in specific tissues could be improved in combination with other nutrients. So far, a variety of nutritional supplements have flooded the market, which contains the compositions of NMN coupled with natural products. However, the synergy and transformation process of NMN has not been fully elucidated. In this study, oral administration of NMN (500 mg/kg) combined with resveratrol (50 mg/kg) or ginsenoside Rh2&Rg3 (50 mg/kg) was used to validate the efficacy of appropriate drug combinations in mice. Compared with NMN alone, NMN combined with resveratrol could increase the levels of NAD+ in the heart and muscle by about 1.6 times and 1.7 times, respectively, whereas NMN coupled with ginsenoside Rh2&Rg3 could effectively improve the level of NAD+ in lung tissue for approximately 2.0 times. Our study may provide new treatment ideas for aging or diseases in cardiopulmonary caused by decreased NAD+ levels.
Distributed iterative learning temperature control for large‐scale buildings
Authors: He Xun , Shen Dong
Published: July 2022

This article investigates the distributed iterative learning control for heating ventilation and air condition (HVAC) systems. Large‐scale building HVAC systems consisting of several subsystems are generally disturbed by the external environment and random human activities. The control objective is to achieve all units of the large‐scale building consistently maintaining the desired temperature. A distributed learning control (DLC) scheme with a decreasing gain is proposed and analyzed for the first time. To accelerate convergence speed, an adaptation mechanism is introduced to generate an adaptive learning gain sequence. Then, an accelerated distributed learning control (ADLC) scheme is designed to improve the transient convergence performance. For the DLC scheme, the input error is proved convergent to zero in the mean‐square sense, whereas the convergence with probability 1 is proved for the ADLC scheme. Numerical results are presented to verify the effectiveness of the proposed schemes.
Maximum turn‐off control for discrete‐time linear systems
Authors: Iwata Takumi , Azuma Shun‐ichi , Ariizumi Ryo , Asai Toru
Published: July 2022

We aim to address the problem of finding a control input maximizing the time instants when all control channels take a zero‐value (are turned off) while stabilizing the system to zero over a given horizon length. This problem is called the maximum turn‐off control problem. To solve it, we reduce the problem into a block‐sparse optimization problem with respect to the control input sequence, where the norm of the control input sequence is the objective function that must be minimized. Because the problem is not convex, we introduce a relaxed problem based on the norm, which is a convex function, and characterize the equivalence relation between the original and relaxed problems using the so‐called block restricted isometry property (block‐RIP). Based on the equivalence, the solution can be obtained by solving the convex relaxed problem. However, the block‐RIP is not easy to interpret and verify. Thus, we propose the notion of sparse controllability Gramians, which is an extension of the controllability Gramians, and show that the block‐RIP can be interpreted by the eigenvalues of the sparse controllability Gramian. This study presents an easy‐to‐check condition of the block‐RIP. Moreover, the above control framework is extended to a model predictive control scheme. These results are demonstrated using numerical examples.
Comparison of the accuracy of two UAV‐mounted uncooled thermal infrared sensors in predicting river water temperature
Authors: Niwa Hideyuki
Published: July 2022

Measurement by a unmanned aerial vehicles (UAV) equipped with thermal infrared sensors has great potential as a new technique for understanding the spatial heterogeneity of river water temperature; however, the measurement technique has not been established yet. Therefore, this study measured surface and water temperatures using two uncooled thermal infrared sensors, which are commercially available, for 7 months, to obtain knowledge to establish a method for predicting the river water temperature using uncooled thermal infrared sensors mounted on UAVs. The survey covered a 500 m section upstream from the confluence of the Inukai River in the Katsura River of the Yodo River system, in Japan. DJI Zenmuse XT2 and MicaSense Altum were mounted on a DJI Matrice 300 at the same time and took images seven times at intervals of approximately 1 month between June 2021 and January 2022. The water temperature and depth were measured at several locations within the study area within 1.5 hr after the UAV acquisition. Then, the relationship between the measured water temperature and the surface temperature extracted from the thermal infrared orthorectified mosaic image was analyzed. Altum was more suitable than XT2 for obtaining thermal infrared orthorectified mosaic images with less inconsistencies among courses in the surface temperature range, and the difference in water temperature was also smaller, making it suitable for understanding the river water temperature. To predict water temperature from surface temperature, actual measured data of water temperature is necessary, but I demonstrated that it is possible to measure the river water temperature in a spatially continuous manner.
A New Blending Method for the Preparation of Macroporous Open‐cell Polyvinyl Formaldehyde Foams with High Water‐Absorption Capacity
Authors: Li Yuanpeng , Pu Taohong , Wu Xun
Published: July 2022

A new blending method for the preparation of a series of macroporous open‐cell polyvinyl formaldehyde (PVF) foams is reported here. Mechanism of foam‐formation was detailedly analyzed and it was found that the addition of polyvinyl alcohol (PVA) with a low degree of polymerization was important and crucial for the formation of PVF foams. Further, the addition of PVA with a low degree of polymerization is beneficial for the improvement of water solubility. The structures and properties of PVF foams were investigated by Fourier transform infrared (FTIR), scanning electron microscope (SEM), thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). The macroporous open‐cell PVF foams had a pore size ranging from 120.88 to 16.16 μm with an increased degree of acetalization and the water absorption capacity increased with the addition of PVA with a low degree of polymerization. PVF foams generally have higher thermal stability because of their cross‐linked network structure. The highest water absorption capacity of the PVF foam obtained presently can reach up to 960 wt%, which is much higher than most PVF foams reported so far.
Transition Metal Complexes of 2,6‐Dibenzhydryl Derived Bisphosphine: Synthesis, Structural Studies and Palladium Complex Promoted Suzuki‐Miyaura Reactions
Authors: Pandey Madhusudan K. , Kote Basvaraj S. , Mondal Dipanjan , Kunchur Harish S. , Radhakrishna Latchupatula , Balakrishna Maravanji S.
Published: July 2022

Transition metal chemistry of [Ar*N(CH2PPh2)2] (1) derived from the sterically demanding backbone 2,6‐dibenzhydryl‐4‐methylphenyl core is described. The reactions of 1 with 30 % aq. H2O2 and S8 afforded bischalcogenides [Ar*N(CH2P(O)Ph2)2] (2) and [Ar*N(CH2P(S)Ph2)2] (3), respectively. Treatment of 1 with [M(COD)Cl2] (M=Pd, Pt) in 1 : 1 molar ratios produced chelate complexes cis‐[MCl2{Ar*N(CH2PPh2)2}‐κ2‐P,P] (4, M=Pd; 5, M=Pt), whereas similar reaction between 1 and [Pd(η3‐C3H5)Cl]2 afforded dinuclear complex [{Pd(η3‐C3H5)Cl}2{Ar*N(CH2PPh2)2}‐κ1‐P,P] (6). The reaction of 1 with [Ru(η5‐C5H5)Cl(PPh3)2] in 1 : 1 ratio yielded [{Ru(η5‐C5H5)Cl}{Ar*N(CH2PPh2)2}‐κ2‐P,P] (7). Treatment of 1 with [M(C5H11N)2(CO)4] (M=Mo, W) in 1 : 1 molar ratios afforded cis‐[M(CO)4{Ar*N(CH2PPh2)2}‐κ2‐P,P] (8, M=Mo; 9, M=W). The reaction of 1 with copper(I) halides in 1 : 1 molar ratios produced [Cu(μ2‐X)]2 dinuclear complexes [{Cu(μ2‐X)}2{Ar*N(CH2PPh2)2}2‐κ2‐P,P}] [10, X=Cl; 11, X=Br; and 12, X=I]. Most of these compounds show various C−H⋅⋅⋅π interactions. Bischalcogenides 2 and 3 showed intramolecular hydrogen bonding type interactions, C−H⋅⋅⋅O (2.554 Å) and C−H⋅⋅⋅S (2.825 Å) between the methylene hydrogens of –NCH2PPh2 groups with O or S atoms, which was also evinced by QTAIM and NCI analysis. Bisphosphine 1 was found to be very effective in palladium catalyzed Suzuki‐Miyaura couplings of aryl chlorides with aryl boronic acids.
Polymer Supported Methionine Selenoxide as an Excellent Immobilized Oxidant for the Formation of Disulfide Bonds in Peptides
Authors: Wang Yafang , Xing Yueyue , Sun Jingjing , Song Changing , Shen Shigang , Huo Shuying
Published: July 2022

Two PEG‐based polymer supported methionine selenoxide (MeSeO) named TentaGel‐MetSeO and PEG‐MetSeO were synthesized and used as immobilized oxidants for the purpose of formation of disulfide bonds in peptides under aqueous conditions. Peptide disulfide bonds were successfully synthesized by use of the two immobilized oxidants. Moreover, the oxidation of the methionine residue to its sulfoxide derivate was not observed. By comparison, the yield of disulfide‐containing peptide via PEG‐MetSeO oxidation is higher than that of the disulfide‐containing peptide via TentaGel‐MetSeO oxidation. PEG‐MetSeO can be used at least 10 cycles without the significant yield decrease. The two immobilized oxidants can be separated from the reaction mixture using filtration, making the peptide synthesis more easily.
Lewis Base‐catalyzed β‐Addition of (Arylsulfonyl) fluoromethane Derivatives to Allenoates
Authors: Liu Yong‐Liang , Wang Xiao‐Ping , Li Ya
Published: July 2022

A highly selective TMG‐catalyzed β‐addition of (arylsulfonyl)fluoromethane derivatives to allenoates has been developed. Cyano, nitro, and ester‐functionalized (arylsulfonyl)fluoromethanes are all suitable substrates, giving a series of structurally diverse β‐addition products bearing a stereogenic fluorinated carbon center. A possible reaction pathway is also presented.
A Polythiophene Material Featuring a Conjugated Carbonyl Side Group as an Anode for Lithium‐Ion Batteries
Authors: Zhang Chengjun , Chen Sha , Zhou Guangying , Hou Qiong , Wang Yuhai , Shi Guang
Published: July 2022

Converting small organic molecules to their lithium salts or polymerization effectively solves the capacity fading caused by the dissolution of small organic molecules in electrolytes. While polymer lithium salts have the characteristics of small molecular lithium salts and polymers and can obtain good cycle stability and rate performance. The 3‐carboxylithium substituted thiophene (3‐TCOOLi) and polymer (P3‐TCOOLi) anode materials for lithium‐ion batteries were synthesized, and their electrochemical properties were compared. Compared with the small‐molecule lithium salt 3‐TCOOLi electrode, the polymer P3‐TCOOLi electrode exhibits superior cycling and rate performance. The P3‐TCOOLi electrode still has a specific capacity of 390 mAh g−1 after 100 cycles at a current density of 50 mA g−1. During the rate charge and discharge process, when the current density increased to 1000 mA g−1, the specific capacity was 305 mAh g−1. It shows that the idea of small molecule lithium salt polymerization is feasible.
A Potential PIK3CA Inhibitor to Develop an Anticancer Drug
Authors: Vique‐Sánchez José Luis , Benítez‐Cardoza Claudia Guadalupe
Published: July 2022

According to the global cancer statistics published by the American Cancer Society (2020), the incidence and mortality of cancer are rapidly increasing worldwide. Therefore, it is necessary to develop new drugs that have greater effectiveness and lower side effects than the current drugs. In this study we used the PIK3CA enzyme as therapeutic target, because there are studies that showed that PIK3CA plays a critical role to develop cancer, strongly related to tumor proliferation, migration, and clinical prognosis by its functions on the PI33K/AKT signaling pathway. The aim of this research is to determine a selective compound to PIK3CA, by molecular docking using a library of nearly 500,000 compounds, to develop a new anticancer drug to decrease the PIK3CA functions in the cancer processes. It was determined the C5 compound with a cytotoxic effect on in vitro cultures of cancer cell lines, due to a probable specific interaction in PIK3CA, Cys420, Glu453, Glu542, Glu545 amino acids, this region is necessary for the catalytic subunit p110α in the PIK3CA enzyme. This research evaluated the potential anticancer effect of C5 compound with acceptable citotoxicity, toxicity theoretical and LD50 results; other analyses will be necessary to continue this development as a new anticancer drug.
The applications of single‐atom alloys in electrocatalysis: Progress and challenges
Authors: Da Yumin , Jiang Rui , Tian Zhangliu , Han Xiaopeng , Chen Wei , Hu Wenbin
Published: July 2022

The development of cost‐effective and highly efficient electrocatalysts to accelerate distinct electrochemical reactions is essential to help the industry to achieve a low‐carbon footprint. Single‐atom alloys (SAAs) with the characteristics of unique electronic structures, well‐defined active sites, and maximum atom utilization demonstrate promising potential to replace traditional noble metal catalysts. SAAs are expected to tailor the adsorption properties of reaction species, thus promoting electrocatalytic behaviors. Herein, representative synthetic strategies including wet chemistry, galvanic replacement, dealloying, and atomic layer deposition are introduced, followed by a summary of applications of SAAs in hydrogen evolution reaction, oxygen evolution reaction, oxygen reduction reaction, carbon dioxide reduction reaction, and ethanol electro‐oxidation to provide an in‐depth understanding of the structure–activity relationship. Moreover, the challenges and perspectives in this emerging field of SAAs are discussed.
“Wearing a Mask Won't Protect Us from Our History”: The Impact of COVID‐19 on Black Children and Families
Authors: Bogan Erin , Adams‐Bass Valerie N. , Francis Lori A. , Gaylord‐Harden Noni K. , Seaton Eleanor K. , Scott Judith C. , Williams Joanna L.
Published: July 2022

The data on COVID‐19 show an irrefutable and disturbing pattern: Black Americans are contracting and dying from COVID‐19 at rates that far exceed other racial and ethnic groups. Due to historical and current iterations of racism, Black Americans have been forced into conditions that elevate their risk for COVID‐19 and consequently place Black children at the epicenter of loss across multiple domains of life. The current paper highlights the impact of the pandemic on Black children at the individual, family, and school levels. Based on an understanding of the influence of structural racism on COVID‐19 disparities, policy recommendations are provided that focus on equitable access to quality education, home ownership, and employment to fully address the needs of Black children and families during and after the pandemic. Research, practice, and policy recommendations are made to journal editors, funding agencies, grant review panels, and researchers regarding how research on COVID‐19 should be framed to inform intervention efforts aimed at improving the situation of Black children and families.
The first belemnite of boreal ancestry from the Early Cretaceous (Valanginian) of the western Tethys: implications for belemnite ecology
Authors: Mutterlose Jörg , Picollier Marie‐Claire , Dzyuba Oksana
Published: July 2022

The first occurrence of the belemnite species Liobelus acrei (formerly Acroteuthis acrei) is reported from the Lower Cretaceous (Valanginian) of the Vocontian Basin (VB; south‐east France). This first record of the genus Liobelus (Family Cylindroteuthididae), which is commonly attributed to the latest Jurassic and Early Cretaceous of the Boreal Realm, revises the spatial distribution pattern of boreal belemnites significantly. The Valanginian belemnite assemblages of the VB are dominated by genera of Tethyan ancestry, including both Duvaliidae (Berriasibelus, Castellanibelus, Duvalia, Pseudobelus) and Belemnopseidae (Adiakritobelus, Hibolithes, Mirabelobelus, Vaunagites). These two groups of Tethyan taxa comprise more than 99.9% of the belemnite‐rich assemblages of the Valanginian of the VB. The occurrence of a boreal specimen documents an isolated immigration of belemnites from the north in the early Valanginian. At the same time most Tethyan belemnite taxa are absent from the Boreal Realm, only Duvalia, Pseudobelus and Hibolithes have been described from North‐East Greenland, and Hibolithes from Svalbard. Based on these diverging biogeographical patterns of the Tethyan belemnite genera we establish two taxonomically different belemnite faunas: Tethyan Fauna 1 (Duvalia, Pseudobelus, Hibolithes), which has a near global, Tethyan‐wide and even boreal distribution, and Tethyan Fauna 2 (Adiakritobelus, Berriasibelus, Castellanibelus, Mirabelobelus, Vaunagites), which is less widely distributed and is restricted to southern Europe. These different spatial distribution patterns shed light on the ecology, migration patterns and evolution of Early Cretaceous belemnites.
Model‐based systems engineering for a small‐lift launch facility
Authors: Taraila Walter McGee , Asundi Sharanabasaweshwara
Published: July 2022

A study of model‐based systems engineering (MBSE) applied to a small‐lift launch facility is presented. The research uses Systems Modeling Language (SysML) products and functional diagrams to document the ground systems on a launch pad servicing a small class payload (0–2 tons). With the projected growth in launch cadence of small‐lift rockets in the coming decade, there is a need to design increasingly complex launch systems with greater efficiency. The potential improvements in project communication, quality, and productivity are explored by developing a model following the ISO/IEC 15288 technical process framework and the International Council on Systems Engineering (INCOSE) Object‐Oriented Systems Engineering Method (OOSEM) methodology. The stakeholder requirements are defined and analyzed to provide traceability to individual systems and subsystems. An architecture is proposed by generating engineering artifacts such as piping and instrumentation drawings. The concepts are verified and validated by performing engineering trade studies concentrated on the pneumatic and fuel subsystems.
Selective Phosphorylation of RNA‐ and DNA‐Nucleosides under Prebiotically Plausible Conditions
Authors: Bechtel Maximilian , Hümmer Eva , Trapp Oliver
Published: July 2022

Nucleotides play a fundamental role in organisms, from adenosine triphosphate (ATP), the body‘s main source of energy, to cofactors of enzymatic reactions (e. g. coenzyme A), to nucleoside monophosphates as essential building blocks of deoxyribonucleic acid (DNA) and ribonucleic acid (RNA). Although nucleotides play such an elemental role, there is no pathway to date for the selective formation of nucleoside 5′‐monophosphates. Here, we demonstrate a selective reaction pathway for 5’ mono‐phosphorylation for all canonical purine and pyrimidine bases under exceptionally mild prebiotic relevant conditions in water and without using a condensing agent. The pivotal reaction step involves activated imidazolidine‐4‐thione phosphates. The selective formation of non‐cyclic mono‐phosphorylated nucleosides represents a novel and unique route to nucleotides and opens exciting perspectives in the study of the origins of life.
On the safe use of prior densities for Bayesian model selection
Authors: Llorente Fernando , Martino Luca , Curbelo Ernesto , López‐Santiago Javier , Delgado David
Published: July 2022

The application of Bayesian inference for the purpose of model selection is very popular nowadays. In this framework, models are compared through their marginal likelihoods, or their quotients, called Bayes factors. However, marginal likelihoods depend on the prior choice. For model selection, even diffuse priors can be actually very informative, unlike for the parameter estimation problem. Furthermore, when the prior is improper, the marginal likelihood of the corresponding model is undetermined. In this work, we discuss the issue of prior sensitivity of the marginal likelihood and its role in model selection. We also comment on the use of uninformative priors, which are very common choices in practice. Several practical suggestions are discussed and many possible solutions, proposed in the literature, to design objective priors for model selection are described. Some of them also allow the use of improper priors. The connection between the marginal likelihood approach and the well‐known information criteria is also presented. We describe the main issues and possible solutions by illustrative numerical examples, providing also some related code. One of them involving a real‐world application on exoplanet detection.

This article is categorized under:

Statistical Models > Bayesian Models

Statistical Models > Fitting Models

Statistical Models > Model Selection
Direct regulation of TCR rearrangement and expression by E proteins during early T cell development
Authors: Anderson Michele K. , da Rocha Juliana Dutra Barbosa
Published: July 2022

γδ T cells are widely distributed throughout mucosal and epithelial cell‐rich tissues and are an important early source of IL‐17 in response to several pathogens. Like αβ T cells, γδ T cells undergo a stepwise process of development in the thymus that requires recombination of genome‐encoded segments to assemble mature T cell receptor (TCR) genes. This process is tightly controlled on multiple levels to enable TCR segment assembly while preventing the genomic instability inherent in the double‐stranded DNA breaks that occur during this process. Each TCR locus has unique aspects in its structure and requirements, with different types of regulation before and after the αβ/γδ T cell fate choice. It has been known that Runx and Myb are critical transcriptional regulators of TCRγ and TCRδ expression, but the roles of E proteins in TCRγ and TCRδ regulation have been less well explored. Multiple lines of evidence show that E proteins are involved in TCR expression at many different levels, including the regulation of Rag recombinase gene expression and protein stability, induction of germline V segment expression, chromatin remodeling, and restriction of the fetal and adult γδTCR repertoires. Importantly, E proteins interact directly with the cis‐regulatory elements of the TCRγ and TCRδ loci, controlling the predisposition of a cell to become an αβ T cell or a γδ T cell, even before the lineage‐dictating TCR signaling events.

This article is categorized under:

Immune System Diseases > Stem Cells and Development

Immune System Diseases > Genetics/Genomics/Epigenetics
Potential of atmospheric pressure ionization sources for the analysis of free fatty acids in clinical and biological samples by gas chromatography-mass spectrometry
Authors: Görs Paul E. , Wittenhofer Pia , Ayala-Cabrera Juan F. , Meckelmann Sven W.
Published: July 2022

Because of the central role of fatty acids in biological systems, their accurate quantification is still important. However, the impact of the complex matrix of biologically and clinically relevant samples such as plasma, serum, or cells makes the analysis still challenging, especially, when free non-esterified fatty acids have to be quantified. Here we developed and characterized a novel GC–MS method using pentafluorobenzyl bromide as a derivatization agent and compared different ionization techniques such as atmospheric pressure chemical ionization (APCI), atmospheric pressure chemical photoionization (APPI), and negative ion chemical ionization (NICI). The GC-APCI-MS showed the lowest limits of detection from 30 to 300 nM for a broad range of fatty acids and a similar response for various fatty acids from a chain length of 10 to 20 carbon atoms. This allows the number of internal standards necessary for accurate quantification to be reduced. Moreover, the use of pentafluorobenzyl bromide allows the direct derivatization of free fatty acids making them accessible for GC–MS analysis without labor-intense sample pretreatment.