bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of platelet‐rich fibrin on human gingival and periodontal ligament fibroblast proliferation from chronic periodontitis versus periodontally healthy subjects
Authors: Goel Apoorv , Windsor L. Jack , Gregory Richard L. , Blanchard Steven B. , Hamada Yusuke
Published: January 2021

Background

Platelet‐rich fibrin (PRF), an autogenous blood concentrate, contains multiple growth factors and is used as an adjunct in the periodontal regeneration and implant site development procedures to stimulate wound healing. Patient‐related factors such as chronic periodontitis may affect the quality of PRF.

Objectives

This study aimed to investigate and compare PRF's effects from patients diagnosed with generalized moderate or severe chronic periodontitis to patients who presented with intact periodontium on human gingival fibroblast (HGF) and human periodontal ligament fibroblast (HPLF) proliferation.

Materials and methods

A total of 33 ml of whole intravenous blood was collected from each subject and centrifuged at 2700 rpm for 12 min in three 10 ml tubes, and 3 ml of blood was used for Complete Blood Count analysis. Three PRF clots were compressed to produce the membranes and liquid exudate. PRF membrane and 10% liquid exudate were exposed to 20,000 HPLFs/well or 25,000 HGFs/well in triplets from each subject in a 48 cell well plate. After 72 h of incubation, the conditioned media were evaluated by Water Soluble Tetrazolium‐1 assays to determine fibroblast proliferation. Controls included cells alone and media without cells. Complete blood counts were measured.

Results

Subjects in both groups were age and gender‐matched (intact 46.7 ± 11.4 years and periodontitis 54.8 ± 10.4 years, p‐value = 0.1344). Body Mass Index and White Blood Corpuscles in the periodontitis group was significantly higher than the intact group (p = 0.0176 and p = 0.0038) whereas no differences were seen for Red Blood Corpuscles (p = 0.2020), Hemoglobin (p = 0.2290) and Platelets (p = 4,094). There were no significant differences in the HGF and HPLF proliferation with PRF exudates and membranes between intact periodontium and periodontitis groups (all p > 0.05). However, PRF exudates in both groups induced significant more cell proliferation when compared to PRF membranes.

Conclusions

PRF exudates induced significant proliferation of fibroblasts and can play a vital role in wound healing. The current study concluded that PRF membranes, in combination with PRF exudates, can be utilized for their therapeutic and wound healing potential, not affected by the periodontal condition of the patient.
Water as a reactant in the differential expression of proteins in cancer
Authors: Dick Jeffrey M.
Published: January 2021

Introduction. How proteomes differ between normal tissue and tumor microenvironments is an important question for cancer biochemistry. Methods. More than 250 datasets for differentially expressed (up‐ and downregulated) proteins compiled from the literature were analyzed to calculate the stoichiometric hydration state, which represents the number of water molecules in theoretical mass‐balance reactions to form the proteins from a set of basis species. Results. The analysis shows increased stoichiometric hydration state of differentially expressed proteins in cancer compared to normal tissue. In contrast, experiments with different cell types grown in 3D compared to monolayer culture, or exposed to hyperosmotic conditions under high salt or high glucose, cause proteomes to “dry out” as measured by decreased stoichiometric hydration state of the differentially expressed proteins. Conclusion. These findings reveal a basic physicochemical link between proteome composition and water content, which is elevated in many tumors and proliferating cells.
Nonlinear circuits with parallel‐/series‐connected HP‐type memory elements and their characteristic analysis
Authors: Liu Yue , Guo Zhang , Chau Tat Kei , Iu Herbert Ho‐Ching , Si Gangquan
Published: January 2021

In this paper, two nonlinear circuits are constructed based on the HP‐type flux‐/ charge‐controlled memory elements in parallel and series connections. Then, the phasor method is utilized to analyze and verify the frequency doubling mechanism between pinched hysteresis loops and the applied sinusoidal excitation. The expressions of equivalent admittance (denoted as YM) and impedance (denoted as ZM) for memory elements connected in parallel and series and the unified forms of which are also derived, respectively. Moreover, the mathematical models for the parallel‐/serial‐connected circuits are obtained and their characteristics are described. Meanwhile, the dual relationships, which come from the reciprocal relationship between YM and ZM, are also discovered based on their models. Furthermore, the gradual steady‐state oscillation and temporal behaviors are demonstrated for two nonlinear circuits. Finally, the experimental verification shows a good agreement between theoretical analysis and experimental results.
Auto‐clamping interface circuit for high electron mobility transistor‐based heavy metal detection sensor
Authors: Kishore Kaushal , Chaturvedi Nidhi , Akbar SA
Published: January 2021

In this paper, we present an improved full Wilson current mirror‐based interface system, which utilizes an auto‐balancing technique, for High Electron Mobility Transistor (HEMT)‐based biochemical sensors. The auto‐tuning technique maintains a constant voltage across the sensor and simultaneously provides an output voltage proportional to the measurand. The proposed circuit is particularly useful for HEMT‐based sensors with large offset current since the design performs base current compensation. The design and analysis of the proposed circuit are verified experimentally on a prototype Printed Circuit Board (PCB). The effectiveness of the circuit is proven by carrying out repeated experiments for evaluating linearity, accuracy, and standard deviation. The obtained result of the prototype shows that the proposed circuit is able to work from 300 Ω to 2.1 kΩ with a relative error of less than ±2%. The prototype is finally tested with an in‐house fabricated HEMT‐based heavy metal sensor. The measurement range of the proposed circuit is tunable according to the sensor operating range, which enables the potential use of the proposed circuit for a wide range of HEMT‐based sensors.
An energy‐efficient switching scheme based on distributing most significant bit capacitors for successive approximation register analog‐to‐digital converter
Authors: Yu Zhiguo , Wang Tao , Song Xinyu , Wang Tian , Liu Kangsheng , Gu Xiaofeng
Published: January 2021

This paper proposes an energy‐efficient switching scheme for successive approximation register (SAR) analog‐to‐digital converter (ADC). Compared with the traditional scheme with only two reference voltages, this switching scheme can save 95.93% of the switching energy and reduce the total capacitance by 75%. The most significant bit (MSB) capacitor is distributed into two parallel binary‐weighted capacitors, which results in a 1/2CV2ref reduction in the switching energy in the third comparison. The dummy capacitors are replaced with two sets of unit capacitors to avoid using the reference voltage of 1/2Vref during the last comparison.
A functional assembly framework based on implementable neurobionic material
Authors: Zou Xiang , Jiang Conglin , Sun Yirui , Zhao Donghua , Tong Yusheng , Mao Ying , Chen Liang
Published: January 2021

Neurobionic material is an emerging field in material and translational science. For material design, much focus has already been transferred from von Neumann architecture to the neuromorphic framework. As it is impractical to reconstruct the real neural tissue solely from materials, it is necessary to develop a feasible neurobionics framework to realize advanced brain function. In this study, we proposed a mathematical neurobionic material model, and attempted to explore advanced function only by simple and feasible structures. Here an equivalent simplified framework was used to describe the dynamics expressed in an equation set, while in vivo study was performed to verify simulation results. In neural tissue, the output of neurobionic material was characterized by spike frequency, and the stability is based on the excitatory/inhibitory proportion. Spike frequency in mathematical neurobionic material model can spontaneously meet the solution of a nonlinear equation set. Assembly can also evolve into a certain distribution under different stimulations, closely related to decision making. Short‐term memory can be formed by coupling neurobionic material assemblies. In vivo experiments further confirmed predictions in our mathematical neurobionic material model. The property of this neural biomimetic material model demonstrates its intrinsic neuromorphic computational ability, which should offer promises for implementable neurobionic device design.
Mesenchymal stem cell‐glioblastoma interactions mediated via kinin receptors unveiled by cytometry
Authors: Pillat Micheli Mainardi , Oliveira‐Giacomelli Ágatha , das Neves Oliveira Mona , Andrejew Roberta , Turrini Natalia , Baranova Juliana , Lah Turnšek Tamara , Ulrich Henning
Published: January 2021

Glioblastoma (GBM) is one of the most malignant and devastating brain tumors. The presence of highly therapy‐resistant GBM cell subpopulations within the tumor mass, rapid invasion into brain tissues and reciprocal interactions with stromal cells in the tumor microenvironment contributes to an inevitable fatal prognosis for the patients. We highlight the most recent evidence of GBM cell crosstalk with mesenchymal stem cells (MSCs), which occurs either by direct cell–cell interactions via gap junctions and microtubules or cell fusion. MSCs and GBM paracrine interactions are commonly observed and involve cytokine signaling, regulating MSC tropism toward GBM, their intra‐tumoral distribution, and immune system responses. MSC‐promoted effects depending on their cytokine and receptor expression patterns are considered critical for GBM progression. MSC origin, tumor heterogeneity and plasticity may also determine the outcome of such interactions. Kinins and kinin‐B1 and ‐B2 receptors play important roles in information flow between MSCs and GBM cells. Kinin‐B1 receptor activity favors tumor migration and fusion of MSCs and GBM cells. Flow and image (tissue) cytometry are powerful tools to investigate GBM cell and MSC crosstalk and are applied to analyze and characterize several other cancer types.
New cytometry tools for immune monitoring during cancer immunotherapy
Authors: Sanjabi Shomyseh , Lear Sean
Published: January 2021

The success of cancer immunotherapy (CIT) in the past decade has brought renewed excitement and the need to better understand how the human immune system functions during health and disease. Advances in single cell technologies have also inspired the creation of a Human Cell Atlas to identify and describe every cell in the human body with the intention of elucidating how to “fix” the ones that fail normal function. For example, treatment of cancer patients with immune checkpoint blockade (ICB) antibodies can reinvigorate their T cells and produce durable clinical benefit in a subset of patients, but a number of resistance mechanisms exist that prohibit full benefit to all treated patients. Early detection of biomarkers of response and mechanisms of resistance are needed to identify the patients who can benefit most from ICB. A noninvasive approach to predict treatment outcomes early after immunotherapies is a longitudinal analysis of peripheral blood immune cells using flow cytometry. Here we review some of the advances in our understanding of how ICB antibodies can re‐invigorate tumor‐specific T cells and also highlight the recent advances in high complexity flow cytometry, including spectral cytometers, that allow longitudinal sampling and deep immune phenotyping in clinical settings. We encourage the scientific community to utilize advanced cytometry platforms and analyses for immune monitoring in order to optimize CIT treatments for maximum clinical benefit.
A flow cytometric assay for HLA‐DR expression on monocytes validated as a biomarker for enrollment in sepsis clinical trials
Authors: Quadrini Karen J. , Patti‐Diaz Lisa , Maghsoudlou Jasmin , Cuomo Joanne , Hedrick Michael Nathan , McCloskey Thomas W.
Published: January 2021

Purpose

Decreased expression of HLA‐DR on monocytes (mHLA‐DR) is a reliable indicator of immunosuppression in patients with sepsis and is correlated with increased risk of secondary infection and mortality. A flow cytometry‐based laboratory developed test for the measurement of mHLA‐DR in whole blood was validated for clinical trial enrollment, which is considered medical decision‐making, for patients with severe sepsis or septic shock.

Methods

The BD Quantibrite™ anti‐HLA‐DR/anti‐monocyte reagent measures antibodies bound per cell of HLA‐DR on CD14+ monocytes. The mHLA‐DR assay was planned to support inclusion/exclusion of patients for a clinical trial and was validated according to New York State Department of Health (NYSDOH) requirements for a new non‐malignant leukocyte immunophenotyping assay.

Results

Normal, healthy donor and sepsis patient samples were stable up to 72 h post‐collection in Cyto‐Chex BCT phlebotomy tubes. Pre‐determined acceptance criteria were met for precision parameters (average %CV ≤ 20%) and global laboratory‐to‐laboratory comparisons (average %Δ ≤ 20%). The approaches taken to evaluate and report accuracy, analytical specificity and sensitivity, reportable range, reference interval, and the proposed multi‐level quality control were accepted by NYSDOH.

Conclusions

In this study, the validation strategy necessary when the intended use of assay results changes from exploratory to medical decision making (patient enrollment), which successfully resulted in regulatory approval, is described.
Full‐scene network security protection system based on ubiquitous power Internet of things
Authors: Wang Jiao
Published: January 2021

Power Internet of things network technology has a “double‐edged sword” effect; on one hand, let us feel fast and convenient, but on the other hand, we are wandering in the network security. At the same time of paying more attention to the quality of human life, it is also necessary to take into account the network security issues related to the power Internet of things. Therefore, this paper aims to study the full‐scene network security protection system based on ubiquitous power Internet of things, which is an important topic at present. This research investigates the effectiveness of the Internet of Things in the network security protection system in general scenarios by investigating the traditional network security risk index and analyzing the excellent performance of the Internet of Things, aiming at the security risks of traditional network servers. In actual application scenarios, the Internet of Things can protect the entire network system in an all‐round way anytime and anywhere. This powerful defense performance is unmatched by traditional networks. Big data intelligent monitoring system is used to monitor the actual operation of all‐weather and all‐scene network protection system. Experimental data show that in the ubiquitous power Internet of things environment, although there are still some risks in the operation of grid companies and other intelligent terminals, the number of security risks is significantly lower than that of the traditional Internet of things. The significance of “ubiquitous” power Internet of things is the all‐scene network security protection system that works all day and all the time. Integrated servers can better protect against security risks than single servers. Experimental data shows that the full‐scenario network security protection system in the Internet of Things effectively integrates the facility resources in the power system and the communication system, and it improves the company’s perception of the entire actual scene during the operation. At the same time, it also promotes the integration of corporate information and provides intelligent support for corporate decision‐making.
Reconfigurable broadband printed monopole antenna for portable smart IoT applications
Authors: Al‐Janabi Mustafa Adnan , Kayhan Sema K.
Published: January 2021

The proposed work presents a design of a smart printed monopole antenna separated from a Hexagonal Matching Load (HML) with an air gap. The patch is fed by a coplanar waveguide, while the HML is connected to the ground plane through two pin diodes to realize antenna reconfiguration through controlling the surface current motion. The antenna structure is mounted on FR‐4 epoxy substrate with size of 23 mm × 30 mm to fit the portable devices. After running four different switching scenarios, an observable change in the antenna performance is demonstrated. The proposed antenna provides a gain of 3.1 dBi at 2.45 GHz when the two diodes are switched ON. However, the antenna gain is changed to 1.6 dBi when the two diodes are set OFF. It is demonstrated that the proposed technique shows an effective approach to control the antenna performance without the need for DC blocking capacitor for RF choke. Nevertheless, the Specific Absorption Rate (SAR) effects are evaluated with respect to the human head tissues for all considered scenarios. Finally, the antenna radiation leakages to the human body are also tested numerically and experimentally for validation.
Efficacy of a combination approach using subcision, fillers, and fractional carbon dioxide laser for the treatment of facial acne scars in Fitzpatrick skin types IV–VI
Authors: Kapoor Rinky , Vadera Sapna , Shome Debraj
Published: January 2021

Introduction

Acne is one of the most common skin diseases, causing scars as a common and persistent complication. A single modality of treatment is not completely effective, and hence a combination of therapeutic modalities is required for the treatment. As the condition is very distressing in nature and leaves an impact at a psychological level, the patient often seeks quick results.

Aims

Efficacy of combined approach using subcision and fillers followed by fractional carbon dioxide laser for the treatment of facial acne scars in Fitzpatrick IV–VI skin types.

Methods

One hundred sixty‐five patients with Fitzpatrick IV–VI skin types and Grades 2–4 acne scars, as per Goodman and Baron Acne Grading Scale, were enrolled. Subcision followed by hyaluronic acid filler was performed initially, followed by fractional carbon dioxide laser 2 weeks later. Standardized digital global photographs were obtained before treatment, before every laser session, and 6 months after the last laser session.

Results

Using Goodman and Baron's Global Acne Scarring System, the patients showed significant improvement of both clinician and subjective scores in all grades of acne scars. No significant adverse events were noted.

Conclusion

To the best of our knowledge, this is the first study to date which involves the combined approach of subcision and fillers, followed by fractional carbon dioxide laser sessions for the treatment of acne scars. The results show significant and persistent improvement, without considerable complications, in Fitzpatrick's skin types IV–VI. This protocol should thus be considered for the management of acne scars of the face.
Doping detection in animals: A review of analytical methodologies published from 1990 to 2019
Authors: Moreira Fernando , Carmo Helena , Guedes de Pinho Paula , Bastos Maria de Lourdes
Published: January 2021

Despite the impressive innate physical abilities of horses, camels, greyhounds, or pigeons, doping agents might be administered to these animals to improve their performance. To control these illegal practices, anti‐doping analytical methodologies have been developed. This review compiles the analytical methods that have been published for the detection of prohibited substances administered to animals involved in sports over 30 years. Relevant papers meeting the search criteria that discussed analytical methods aiming to detect and/or quantify doping substances in animal biological matrices published from 1990 to 2019 were considered. A total of 317 studies were included, of which 298 were related to horses, demonstrating significant advances toward the development of doping detection methods for equine sports. However, analytical methods for the detection of doping agents in sports involving other species are lacking. Due to enhanced accuracy and specificity, chromatographic analysis coupled to mass spectrometry detection is preferred over immunoassays. Regarding biological matrices, blood and urine remain the first choice, although alternative biological matrices, such as hair and feces, have been considered. With the increasing number and type of drugs used as doping agents, the analytes addressed in the published papers are diverse. It is very important to continue to detect and quantify these drugs, recognizing those that are most frequently used, in order to punish the abusers, protect animals' health, and ensure a healthier and genuine competition.
Validating the visceral sensitivity index in an eating disorder sample
Authors: Brown Tiffany A. , Reilly Erin E. , Murray Helen Burton , Perry Taylor R. , Kaye Walter H. , Wierenga Christina E.
Published: January 2021

Objective

Individuals with eating disorders (EDs) often have difficulty tolerating uncomfortable body sensations. As such, anxiety sensitivity specific to gastrointestinal (GI) sensations, has relevance for EDs. However, to date, no validated measures of this construct exist in EDs. Thus, the present study sought to validate the visceral sensitivity index (VSI), a 15‐item measure originally validated in an irritable bowel syndrome sample, in an ED sample and explore associations with ED symptoms.

Method

Two hundred and sixty‐six adolescents (n = 116) and adults (n = 150) in an ED partial hospital program completed the VSI and related measures at admission. Confirmatory factor analysis examined the factor structure of the VSI and hierarchical regression analyses explored associations between the VSI and ED symptoms.

Results

The original version of the VSI had adequate model fit. An alternative 13‐item model removing specific items with poor fit and less theoretical relevance to EDs also demonstrated good fit. The 15‐item and 13‐item VSI had strong internal consistency (α = .93–.94), and correlation results supported the convergent and divergent validity of both versions. Higher visceral sensitivity was associated with elevated body dissatisfaction, cognitive restraint, purging, restricting, and excessive exercise (p‐values <.05), beyond length of illness, body mass index, and trait anxiety.

Discussion

Results support the relevance of GI‐specific anxiety in EDs and suggest that the original 15‐item VSI and modified 13‐item VSI have strong psychometric properties in an ED sample. Given comparable model fit and psychometric properties, both versions of the VSI may be used for future ED research.
Transgenerational effect alters the interspecific competition between two dominant species in a temperate steppe
Authors: Li Yang , Hou Longyu , Yang Liuyi , Yue Ming
Published: January 2021

One of the key aims of global change studies is to predict more accurately how plant community composition responds to future environmental changes. Although interspecific relationship is one of the most important forces structuring plant communities, it remains a challenge to integrate long‐term consequences at the plant community level. As an increasing number of studies have shown that maternal environment affects offspring phenotypic plasticity as a response to global environment change through transgenerational effects, we speculated that the transgenerational effect would influence offspring competitive relationships. We conducted a 10‐year field experiment and a greenhouse experiment in a temperate grassland in an Inner Mongolian grassland to examine the effects of maternal and immediate nitrogen addition (N) and increased precipitation (Pr) on offspring growth and the interspecific relationship between the two dominant species, Stipa krylovii and Artemisia frigida. According to our results, Stipa kryloii suppressed A. frigida growth and population development when they grew in mixture, although immediate N and Pr stimulated S. kryloii and A. frigida growth simultaneously. Maternal N and Pr declined S. krylovii dominance and decreased A. frigida competitive suppression to some extent. The transgenerational effect should further facilitate the coexistence of the two species under scenarios of increased nitrogen input and precipitation. If we predicted these species' interspecific relationships based only on immediate environmental effects, we would overestimate S. krylovii's competitive advantage and population development, and underestimate competitive outcome and population development of A. frigida. In conclusion, our results demonstrated that the transgenerational effect of maternal environment on offspring interspecific competition must be considered when evaluating population dynamics and community composition under the global change scenario.
Geometric analysis of regime shifts in coral reef communities
Authors: Tekwa Edward W. , McManus Lisa C. , Greiner Ariel , Colton Madhavi A. , Webster Michael M. , Pinsky Malin L.
Published: January 2021

Coral reefs are among the many communities believed to exhibit regime shifts between alternative stable states, single‐species dominance, and coexistence. Proposed drivers of regime shifts include changes in grazing, spatial clustering, and ocean temperature. Here, we distill the dynamic regimes of coral–macroalgal interaction into a three‐dimensional geometry based on stability, akin to thermodynamic phase diagrams of state transitions, to facilitate analysis. Specific regime‐shifting forces can be understood as trajectories through the cubic regime geometry. This geometric perspective allows us to understand multiple forces simultaneously in terms of the stability and persistence of interacting species. For example, in a coral–macroalgal community, grazing on macroalgae leads to alternative stable states when there is no spatial clustering (e.g., high habitat connectivity), while warming decreases coexistence. However, with spatial clustering, grazing promotes coexistence because of elevated local intraspecific competition. The geometry of regime shifts provides a general framework to analyze two‐species communities and can help conservation efforts navigate complexity and abrupt environmental changes.
Relationship between body mass index, cardiovascular biomarkers and incident heart failure
Authors: Suthahar Navin , Meems Laura M.G. , Groothof Dion , Bakker Stephan J.L. , Gansevoort Ron T. , van Veldhuisen Dirk J. , de Boer Rudolf A.
Published: January 2021

Aims

There are limited data examining whether body mass index (BMI) influences the association between cardiovascular biomarkers and incident heart failure (HF).

Methods and results

Thirteen biomarkers representing key HF domains were measured: N‐terminal pro‐B‐type natriuretic peptide (NT‐proBNP), mid‐regional pro‐A‐type natriuretic peptide (MR‐proANP), cardiac troponin T (cTnT), C‐reactive protein, procalcitonin, galectin‐3, C‐terminal pro‐endothelin‐1 (CT‐proET‐1), mid‐regional pro‐adrenomedullin, plasminogen activator inhibitor‐1, copeptin, renin, aldosterone, and cystatin‐C. Associations of biomarkers with BMI were examined using linear regression models, and with incident HF using Cox regression models. We selected biomarkers significantly associated with incident HF, and evaluated whether BMI modified these associations. Among 8202 individuals, 41% were overweight (BMI 25–30 kg/m2), and 16% were obese (BMI ≥30 kg/m2). Mean age of the cohort was 49 years (range 28–75), and 50% were women. All biomarkers except renin were associated with BMI: inverse associations were observed with NT‐proBNP, MR‐proANP, CT‐proET‐1 and aldosterone whereas positive associations were observed with the remaining biomarkers (all P ≤ 0.001). During 11.3 ± 3.1 years of follow‐up, 357 HF events were recorded. Only NT‐proBNP, MR‐proANP and cTnT remained associated with incident HF (P < 0.001), and a significant biomarker*BMI interaction was not observed (interaction P > 0.1). Combined NT‐proBNP and cTnT measurements modestly improved performance metrics of the clinical HF model in overweight (ΔC‐statistic = 0.024; likelihood ratio χ2 = 38; P < 0.001) and obese (ΔC‐statistic = 0.020; likelihood ratio χ2 = 32; P < 0.001) individuals.

Conclusions

Plasma concentrations of several cardiovascular biomarkers are influenced by obesity. Only NT‐proBNP, MR‐proANP and cTnT were associated with incident HF, and BMI did not modify these associations. A combination of NT‐proBNP and cTnT improves HF risk prediction in overweight and obese individuals.
A Comprehensive Thermogravimetric Analysis Multifaceted Method for the Exact Determination of the Composition of Multifunctional Metal‐Organic Framework Materials
Authors: Lázaro Isabel Abánades
Published: January 2021

Thermogravimetric analysis (TGA) has been widely used as a tool to characterise the composition of materials such as Metal‐Organic Frameworks (MOFs). However, given their multifunctionality and structural complexity, examples of detailed methodologies for the exact calculation of the composition of complex MOF structures and MOF composites are lacking in the literature. Herein, we introduce a new straightforward methodology – based on the experimental ratio between the mass of a structure and its residue – for the exact calculation of the composition of almost any MOF material. We provide a detailed guide for the application of our methodology to different MOF materials, including MOFs in which multiple components decompose fully or partially within the same temperature range as the ligand, and diverse MOF composites, alongside with theoretical calculations demonstrating the exact mathematical determination. The methodology presented here can also be applied to many materials beyond MOFs.
Photoinduced Transformation of Uranyl Nitrate Crown Ether Compounds
Authors: Blanes Díaz Anamar , Kravchuk Dmytro V. , Peroutka Allison A. , Cole Erica , Basile Madeline C. , Forbes Tori Z.
Published: January 2021

The uranyl cation, (U(VI)O2)2+, has previously demonstrated photocatalytic reactivity in organic solutions, which results in the formation of uranyl peroxide species. Past studies indicated that the phototransformation process typically ends with the formation of uranyl peroxide solid phases. In the current study, we explore the transformation of uranyl nitrate crown ether complexes, (18‐crown‐6)[UO2(NO3)2(H2O)2] ⋅ 2 H2O (1 a), (18‐crown‐6)[UO2(NO3)2(H2O)2] (1 b), and (18‐crown‐6) [K(18‐crown‐6)] [(UO2)2(OH)2(NO3)4(H2O)4] (2) in the presence of ethanol to create a uranyl peroxide intermediate phase, (18‐crown‐6)[(UO2)2(O2)(NO3)2(H2O)4] (3), followed by a second alteration to a black solid (4). These compounds were structurally evaluated using both single‐crystal and powder X‐ray diffraction and then further characterized using Raman, NMR, and XPS spectroscopy. The initial transformation from the yellow uranyl nitrate phase (1 a, 1 b, and 2) to the uranyl peroxide (3) follow previously reported mechanisms. The second transformation to the black phase (4) is likely due to additional degradation of the 18‐crown‐6 molecule as a result of hydrogen abstraction and ring‐opening. In addition, we discuss the nature of confinement effects to impact the hydrogen abstraction process and the possibility that nitrate anions in the system may synergistically enhance the degradation process and lead to the formation of 4.
Unusual Reactivity and Photophysical Properties of Platinum(II) Pincer Complexes Containing 6,6'‐Diphenyl‐2,2'‐bipyridine Ligands
Authors: Kozina Daria O. , Shakirova Julia R. , Galenko Ekaterina E. , Porsev Vitaly V. , Gurzhiy Vladislav V. , Khlebnikov Alexander F. , Tunik Sergey P.
Published: January 2021

A series of novel 6,6'‐diphenyl‐2,2'‐bipyridine ligands modified with the substituents at phenyl and bipyridine moieties have been prepared and used in the synthesis of pincer platinum chloride complexes 1–3, [Pt(NNC–R)Cl], where NNC–R – dimethyl 6,6'‐diphenyl‐[2,2'‐bipyridine]‐5,5'‐dicarboxylate (R = H, (1)), dimethyl 6,6'‐bis(4‐fluorophenyl)‐[2,2'‐bipyridine]‐5,5'‐dicarboxylate (R = F (2)), dimethyl 6,6'‐bis(4‐methoxyphenyl)‐[2,2'‐bipyridine]‐5,5'‐dicarboxylate (R = OMe (3)). Reactions of the obtained compounds with triphenylphosphine proceed through unusual pathway, which gives the [Pt(NNC–R)(PPh3)2Cl] products (1a–3a) containing two phosphine ligands, with the chloride retained in coordination sphere and diphenyl‐bipyridine fragment coordinated in η1‐mode through metalation of a pyridine ring. All complexes have been characterized with mass‐spectrometry and NMR spectroscopy, solid‐state structure of 1–3 and 1a, 3a was revealed by using XRD crystallography. The complexes 1–3 are phosphorescent in dichloromethane solution and in solid state. Their photophysical characteristics were determined and analyzed by DFT calculations, which gave assignment of emissive excited state character with the major contribution from the intraligand charge transfer (3ILCT, Ph→bipyridine) and ligand centered (3LC, bipyridine fragment) transitions.
A Facially Coordinating Tris‐Benzimidazole Ligand for Nonheme Iron Enzyme Models
Authors: Gunasekera Parami S. , Abhyankar Preshit C. , MacMillan Samantha N. , Lacy David C.
Published: January 2021

Herein, we report a new tripodal tris‐benzimidazole ligand (Tbim) that structurally mimics the 3‐His coordination environment of certain nonheme mononuclear iron oxygenases. The coordination chemistry of Tbim was explored with iron(II) revealing a diverse set of coordination modes. The aerobic oxidation of biomimetic model substrate diethyl‐2‐phenylmalonate was studied using the Tbim−Fe and Fe(OTf)2.
Highly Reusable and Active Nanometal−Silicon‐Nanowire Array Hybrid Catalysts for Hydrogenation
Authors: Baek Heeyoel , Sato Takuma , Uozumi Yasuhiro , Yamada Yoichi M. A.
Published: January 2021

Highly reusable and active silicon‐nanowire‐array‐stabilized metal‐nanoparticle (SiNA‐MNP) catalysts are prepared for effective hydrogenation under mild conditions. Monometallic Pd (SiNA‐Pd), platinum (SiNA‐Pt), and rhodium (SiNA‐Rh) nanoparticles are prepared on silicon nanowire arrays by the silver‐nanoparticle‐assisted chemical etching of silicon wafers with a variety of metal precursors. Moreover, bimetallic Pd−Rh (SiNA‐PdRh) and Pd−Pt (SiNA‐PdPt) nanoalloy catalysts are also synthesized in one‐pot processes in mixed‐metal solutions without any reducing agent, such as NaBH4 or H2 gas, and other external factors. The SiNA‐MNP catalysts were characterized by SEM/EDX, TEM, XAFS, XRD, and ICP‐MS. Each catalyst was used to hydrogenate trans‐stilbene in a 0.1 MPa hydrogen atmosphere to assess catalytic activity. Moreover, the SiNA‐PdPt and SiNA‐PdRh alloy catalysts are also robust and stable, with high reusability numbers for hydrogenation.
Multiple‐Oxidation‐State Tungsten‐Oxide Clusters on a Carbon Surface as an Intersection between Molecular and Bulk Oxides
Authors: Wakizaka Masanori , Chun Wang‐Jae , Imaoka Takane , Yamamoto Kimihisa
Published: January 2021

Bulk tungsten oxides exhibit a wide range of oxidation states, whereas the oxidation states available in molecular oxides such as polyoxometalates (POMs) is limited. In this paper, tungsten oxide clusters with diameters of 1.2±0.4 (W60Ox/C), 1.1±0.4 (W28Ox/C), and 0.9±0.3 nm (W12Ox/C) were produced in a size‐selective manner on graphitic carbon by using a phenyl‐azomethine‐type dendrimer as a template and applying hydrogen reduction after fixing the dendrimers on a support. X‐ray photoelectron spectroscopy revealed that the W atoms in the clusters exhibited multiple oxidation states, i. e., Wδ+, W4+, W5+, and W6+. Moreover, X‐ray absorption fine structure measurements indicated the W−W bond length of 2.84–2.85±0.01 Å in these clusters. Auto‐oxidation with adventitious oxygen after hydrogen reduction is proposed as a reasonable mechanism for the formation of these clusters on the carbon surface.
Thiourea–Tertiary Amine Promoted Cascade Catalysis: A Tool for Complexity Generation
Authors: Gandhi Soniya , Sivadas Vishnudas , Baire Beeraiah
Published: January 2021

The bifunctional organocatalyst promoted, relay‐cascade catalysis (use of a single catalyst capable of promoting each catalytic cycle in the designed cascade process) has been the hot area of research in recent times, as it enables the green synthesis of complex molecular architectures in an atom, cost, and step‐economic fashion. In this context we summarized the recent developments in the area of the thiourea–tert‐amine based cascade catalysis in the current review article. The discussion was divided into three subsections. double‐, triple‐, and quadruple cascades depending on the number of individual steps involved in the cascade process. In each type there are various combinations of reactions like Michael addition, aldol reaction, Henry reaction, Knoevenagel reaction, cyclization, trans‐esterifications etc. Divergent polycyclic structural frameworks have been achieved employing this cascade catalytic strategy as evidenced in this review. We assume that the current review article would be a handle for the design and development as well as further growth of this potential greener approach.
Phosphoric Acid Mediated Light‐Induced Minisci C−H Alkylation of N‐Heteroarenes
Authors: Jin Songyang , Geng Xinxin , Li Yujun , Zheng Ke
Published: January 2021

Herein, we report an environmentally‐friendly light‐induced Minisci alkylation of N‐heteroarenes with a broad substrate scope using diphenyl phosphate as catalyst under metal‐ and photocatalyst‐free conditions. The radical precursor redox‐active esters (RAEs) were introduced as alkylating reagents for the functionalization of N‐heteroarene derivatives including pyridine, quinoline, and isoquinoline. Mechanistic studies suggested that diphenyl phosphate played a key role via hydrogen bonding in the catalytic cycle.
Synthesis and Determination of Absolute Configuration of Zealexin A1, a Sesquiterpenoid Phytoalexin from Zea mays
Authors: Yajima Arata , Shimura Mikaho , Saito Tatsuo , Katsuta Ryo , Ishigami Ken , Huffaker Alisa , Schmelz Eric A.
Published: January 2021

The enantioselective synthesis of zealexin A1, a sesquiterpene phytoalexin isolated from maize Zea mays is described for the first time. Our methodology for the total synthesis of zealexin A1 involved the stereoselective construction of the stereogenic center via enzymatic resolution followed by Johnson–Claisen rearrangement. The absolute configuration of the natural product was determined through gas chromatography analyses for the methyl esters for both synthetic and natural zealexin A1.
Real‐world effectiveness and tolerability of carbamazepine and oxcarbazepine in 354 patients with trigeminal neuralgia
Authors: Di Stefano Giulia , De Stefano Gianfranco , Leone Caterina , Di Lionardo Andrea , Di Pietro Giuseppe , Sgro Emanuele , Mollica Cristina , Cruccu Giorgio , Truini Andrea
Published: January 2021

Background

It is widely agreed that carbamazepine and oxcarbazepine are highly effective in the long‐term treatment of trigeminal neuralgia. However, the tolerability of these drugs across the different aetiologies of trigeminal neuralgia is still undetermined.

Methods

In this retrospective, real‐world study, we assessed the effectiveness and tolerability of carbamazepine and oxcarbazepine in a large cohort of patients with classical (254 patients), secondary (60 patients) and idiopathic (40 patients) trigeminal neuralgia. We analysed data using a propensity score analysis to account for selection bias; frequencies of side effects associated with carbamazepine and oxcarbazepine were calculated by adjusting data with the inverse probability of treatment weighting.

Results

The initial proportion of responders was 88.3% with carbamazepine, and 90.9% with oxcarbazepine. The number of refractory patients was significantly higher in idiopathic (15%) and secondary forms (27%) than in classical trigeminal neuralgia (6%; p < .05). In 53 patients treated with carbamazepine (29.6%) and in 22 treated with oxcarbazepine (12.6%), major side effects caused treatment interruption or dosage reduction to an unsatisfactory level. Side effects occurred more frequently in patients treated with carbamazepine (43.6%) than with oxcarbazepine (30.3%, p < .0001). The frequency of treatment discontinuation was higher in patients with secondary and idiopathic forms than in those with classical trigeminal neuralgia (p < .05).

Conclusions

Our real‐world study shows that carbamazepine and oxcarbazepine are effective in most patients with trigeminal neuralgia; nevertheless, side effects are still a major issue, particularly in patients with secondary and idiopathic trigeminal neuralgia.

Significance

Although carbamazepine and oxcarbazepine are effective in most patients with trigeminal neuralgia, their side effects are still a major issue, thus necessitating the development of better‐tolerated drugs.
Voltammetric Detection of Captopril in a Commercial Drug Using a Gold‐Copper Metal‐organic Framework Nanocomposite Modified Electrode
Authors: da Silva Diana Maria , Carneiro da Cunha Areias Madalena
Published: January 2021

We report the application of an electrochemical sensor based on gold‐copper metal‐organic framework immobilized on the surface of a glassy carbon electrode to the detection of captopril (CAP), an angiotensin‐converting enzyme inhibitor. Cyclic voltammetric studies showed that the joint action of gold nanoparticles and copper‐1,3,5‐benzenetricarboxylate (Cu−BTC) enhanced the electrochemical response to the Cu‐captopril complex that is adsorbed onto the surface of the electrode. Release of gold nanoparticles from Au@Cu−BTC not only increased the conductivity of the electrode but also provided a more favorable environment for the deposition of reduced Cu that is catalytically renewed on the electrode surface. The anodic current of the Cu(II)−CAP oxidation peak varied linearly within two concentration ranges, namely 0.5 to 7.0 μmol L−1 and 10 to 2500 μmol L−1, with a limit of detection of 0.047 μmol L−1. The mean recovery for the determination of captopril in commercial tablets was 100.3 % suggesting that the method has considerable potential for future industrial applications.
Virtual power plant implementation scheme in Shenzhen city
Authors: Song Xinming , Deng Yongsheng , Jiao Fengshun , Shi Jing , Cheng Meng , Xiang Qianliang , Yue Chengyan , Zhang Zitong , Li Shujian , Kim Hyoungmi
Published: January 2021

To meet the challenge of the “three highs and one limit” of the Shenzhen power grid operation, the virtual power plant (VPP) is proposed to effectively utilize the flexible distributed energy resources (DERs) to optimize the operation scheme of the distribution network. Firstly, based on the investigation of the available and controllable DERs of the Shenzhen power grid, typical application scenarios representing the characteristics of the Shenzhen power grid are formulated. Secondly, the framework and roadmap of the typical regional VPP in Shenzhen are proposed. Thirdly, a coordinated optimal scheduling strategy for the VPP is proposed to solve the voltage issues caused by overload or other reasons in Shenzhen's distribution network. Finally, a case study is carried out on the distribution networks using that of the Shenzhen Potevio New Energy company, Shenzhen Bay Science and Technology Eco‐Park are connected. The results show that the voltage level of the distribution network can be improved by the proposed optimal control strategy of the VPP, and verify the effectiveness of the proposed VPP scheme and the benefits of the VPP for the Shenzhen power grid operation.
Verification of numerical models for seismic fluid‐structure interaction analysis of internal components in liquid‐filled advanced reactors
Authors: Yu Ching‐Ching , Whittaker Andrew S.
Published: January 2021

Earthquake shaking of a liquid‐filled advanced reactor induces fluid‐structure interaction (FSI) between the reactor vessel (tank), its internal components, and the contained liquid. Seismic design, qualification, and risk assessment of such reactors must consider fluid‐structure responses, their geometries and support conditions, and three‐directional seismic inputs, all of which require numerical simulations. Numerical models used for analysis of safety‐related nuclear equipment must be verified and validated. This paper verifies numerical models of submerged components using analytical solutions. Seismic FSI analysis of the numerical models is performed using the Arbitrary Lagrangian‐Eulerian (ALE) and Incompressible Computational Fluid Dynamics (ICFD) solvers in LS‐DYNA. Prior analytical solutions are reworked in this paper, and calculation errors are identified and corrected. The solutions address frequencies of two concentric cylindrical pipes filled with liquid: the inner pipe is a submerged component, and the outer pipe contains the liquid. A unitless frequency coefficient is defined and presented for pipes of different materials, filled with different liquids, and with a range of dimensions for application to advanced reactors. The numerical models are verified here by comparing the lateral frequencies of submerged components with those calculated using the corrected analytical solutions. Recommendations for verification of numerical models of internal components in advanced reactors for seismic FSI analysis are provided. Although the unitless frequency coefficients and verification procedures are developed for application to advanced nuclear reactors, they are broadly applicable to FSI analysis of submerged components in liquid‐filled vessels such as storage tanks, boilers, and steam generators.
Late Holocene flood magnitudes in the Lower Rhine river valley and upper delta resolved by a two‐dimensional hydraulic modelling approach
Authors: van der Meulen Bas , Bomers Anouk , Cohen Kim M. , Middelkoop Hans
Published: January 2021

Palaeoflood hydraulic modelling is essential for quantifying ‘millennial flood’ events not covered in the instrumental record. Palaeoflood modelling research has largely focused on one‐dimensional analysis for geomorphologically stable fluvial settings because two‐dimensional analysis for dynamic alluvial settings is time consuming and requires a detailed representation of the past landscape. In this study, we make the step to spatially continuous palaeoflood modelling for a large and dynamic lowland area. We applied advanced hydraulic model simulations (1D–2D coupled set‐up in HEC‐RAS with 950 channel sections and 108 × 103 floodplain grid cells) to quantify the extent and magnitude of past floods in the Lower Rhine river valley and upper delta. As input, we used a high‐resolution terrain reconstruction (palaeo‐DEM) of the area in early mediaeval times, complemented with hydraulic roughness values. After conducting a series of model runs with increasing discharge magnitudes at the upstream boundary, we compared the simulated flood water levels with an inventory of exceeded and non‐exceeded elevations extracted from various geological, archaeological and historical sources. This comparison demonstrated a Lower Rhine millennial flood magnitude of approximately 14,000 m3/s for the Late Holocene period before late mediaeval times. This value exceeds the largest measured discharges in the instrumental record, but not the design discharges currently accounted for in flood risk management.