bluuebunny/crossref_metadata_2025 huggingface dataset:
Clinical presentation and long‐term follow‐up of dopamine beta hydroxylase deficiency
Authors: Wassenberg Tessa , Deinum Jaap , van Ittersum Frans J. , Kamsteeg Erik‐Jan , Pennings Maartje , Verbeek Marcel M. , Wevers Ron A. , van Albada Mirjam E. , Kema Ido P. , Versmissen Jorie , van den Meiracker Ton , Lenders Jacques W.M. , Monnens Leo , Willemsen Michèl A.
Published: October 2020

Dopamine beta hydroxylase (DBH) deficiency is an extremely rare autosomal recessive disorder with severe orthostatic hypotension, that can be treated with L‐threo‐3,4‐dihydroxyphenylserine (L‐DOPS). We aimed to summarize clinical, biochemical, and genetic data of all world‐wide reported patients with DBH‐deficiency, and to present detailed new data on long‐term follow‐up of a relatively large Dutch cohort. We retrospectively describe 10 patients from a Dutch cohort and 15 additional patients from the literature. We identified 25 patients (15 females) from 20 families. Ten patients were diagnosed in the Netherlands. Duration of follow‐up of Dutch patients ranged from 1 to 21 years (median 13 years). All patients had severe orthostatic hypotension. Severely decreased or absent (nor)epinephrine, and increased dopamine plasma concentrations were found in 24/25 patients. Impaired kidney function and anemia were present in all Dutch patients, hypomagnesaemia in 5 out of 10. Clinically, all patients responded very well to L‐DOPS, with marked reduction of orthostatic complaints. However, orthostatic hypotension remained present, and kidney function, anemia, and hypomagnesaemia only partially improved. Plasma norepinephrine increased and became detectable, while epinephrine remained undetectable in most patients. We confirm the core clinical characteristics of DBH‐deficiency and the pathognomonic profile of catecholamines in body fluids. Impaired renal function, anemia, and hypomagnesaemia can be part of the clinical presentation. The subjective response to L‐DOPS treatment is excellent and sustained, although the neurotransmitter profile in plasma does not normalize completely. Furthermore, orthostatic hypotension as well as renal function, anemia, and hypomagnesaemia improve only partially.
Binding of direct oral anticoagulants to the FA1 site of human serum albumin
Authors: De Simone Giovanna , Pasquadibisceglie Andrea , di Masi Alessandra , Buzzelli Valeria , Trezza Viviana , Macari Gabriele , Polticelli Fabio , Ascenzi Paolo
Published: October 2020

The anticoagulant therapy is widely used to prevent and treat thromboembolic events. Until the last decade, vitamin K antagonists were the only available oral anticoagulants; recently, direct oral anticoagulants (DOACs) have been developed. Since 55% to 95% of DOACs are bound to plasma proteins, the in silico docking and ligand‐binding properties of drugs apixaban, betrixaban, dabigatran, edoxaban, and rivaroxaban and of the prodrug dabigatran etexilate to human serum albumin (HSA), the most abundant plasma protein, have been investigated. DOACs bind to the fatty acid (FA) site 1 (FA1) of ligand‐free HSA, whereas they bind to the FA8 and FA9 sites of heme‐Fe(III)‐ and myristic acid‐bound HSA. DOACs binding to the FA1 site of ligand‐free HSA has been validated by competitive inhibition of heme‐Fe(III) recognition. Values of the dissociation equilibrium constant for DOACs binding to the FA1 site (ie, calcKDOAC) derived from in silico docking simulations (ranging between 1.2 × 10−8 M and 1.4 × 10−6 M) agree with those determined experimentally from competitive inhibition of heme‐Fe(III) binding (ie, expKDOAC; ranging between 2.5 × 10−7 M and 2.2 × 10−6 M). In addition, this study highlights the inequivalence of rivaroxaban binding to mammalian serum albumin. Given the HSA concentration in vivo (~7.5 × 10−4 M), values of KDOAC here determined indicate that the formation of the HSA:DOACs complexes in the absence and presence of FAs and heme‐Fe(III) may occur in vivo. Therefore, HSA appears to be an important determinant for DOACs transport.
Climate suitability for summer maize on the North China Plain under current and future climate scenarios
Authors: Tang Xiaopei , Liu Haijun
Published: October 2020

Maize production on the North China Plain (NCP) is critical to food security in China; however, currently, it is affected by climate change. Understanding the spatiotemporal distribution of the climate suitability for maize on the NCP in the present and future may help sustainably use climate‐related resources to ensure food security in China. In this study, 30 general circulation models from the Coupled Model Intercomparison Project Phase 5 and a statistical downscaling model (NWAI‐WG) were used to project meteorological data in 2021–2100 under representative concentration pathway 4.5 (RCP4.5) and RCP8.5 for 23 national climatic stations on the NCP. Based on agricultural climate suitability theory and the fuzzy mathematics method, the suitability of temperature, precipitation, and solar radiation on summer maize were analysed. The results showed that temperature suitability is decreasing for 2021–2100, especially during the stages from jointing to maturity; temperature suitability is the lowest in the southwest and increases to the northeast under both scenarios. Compared to 1996–2015, the precipitation suitability in 2021–2100 increases greatly under both scenarios, especially in the central part under RCP4.5 and in the north part under RCP8.5. Solar radiation suitability shows a decreasing trend for 1996–2015, however, an increasing trend for 2021–2100 under both scenarios. At spatial scale, the solar suitability increases from southwest to northeast. The integrated climate suitability under RCP4.5 in 2021–2100 is averaged approximately 0.8 and varies slightly, indicating climate change may do small effect on maize growth, though the high values shifting from the central part in 2021–2040 to the northern part in 2081–2100; however, under RCP8.5, the integrated climate suitability shows a downward trend, indicating that climate change will make many regions less suitable for maize growth. These results could provide basic information for agriculture to adapt to climate change and ensure food security for China.
Biomechanical comparison of five cannulated screw fixation strategies for young vertical femoral neck fractures
Authors: Jiang Dajun , Zhan Shi , Wang Lei , Shi Lewis L. , Ling Ming , Hu Hai , Jia Weitao
Published: October 2020

Vertical femoral neck fractures in patients younger than 65 years of age often require hip‐conserving surgeries. However, traditional fixation strategies using three parallel cannulated screws often fail in such patients due to an unfavorable biomechanical environment. This study compared different cannulated screw fixation techniques in patients via patient‐specific finite element analysis with linear tetrahedral (C3D4) elements. Forty vertical femoral neck fracture models were created based on computed tomography images obtained from eight healthy participants. Five different fixation strategies: alpha, buttress, rhomboid, inverted triangle, and triangle were assessed in walking status. Biomechanical parameters including stiffness, interfragmentary motion in two directions (detachment and shearing), compression force, and maximal implant stress were evaluated. The mean relative coefficient of strain distribution between the finite element analysis and experiment was from 0.78 to 0.94. Stiffness was highest (p < .05) in the buttress group (923.1 N/mm), while interfragmentary motion was lowest (p < .05) in the alpha group. Maximal stress was highest (p < .05) in the buttress group and lowest in the alpha group. Shearing values were significantly lower in the alpha group than in the rhomboid group (p = .004). Moreover, Shearing values were significantly higher (p = .027), while detachment values were significantly lower (p = .027), in the inverted triangle than in the triangle group. Clinical significance: Our results suggest that alpha fixation is the most reliable and biomechanically efficient strategy for young patients with vertical femoral neck fractures. Regular and inverted triangular fixation strategies may be suitable for fractures of different skeletal constructions due to antidetachment/shearing abilities.
Effects of water deficit and nitrogen application on leaf gas exchange, phytohormone signaling, biomass and water use efficiency of oat plants
Authors: Li Li , Ma Haiyang , Xing Jiayi , Liu Fulai , Wang Yaosheng
Published: October 2020

Background: Water and nitrogen (N) are essential resources influencing plant growth and yield. To improve their efficiencies in crop production is challenging because the physiological mechanisms of water and N coupling and their interactive effect on crop water use efficiency (WUE) are not well understood yet.

Aim: The aim of this study was to investigate the physiological responses and phytohormones signaling in oats in response to soil water status and N supply under fertigation, to explore the mechanisms regulating plant growth and WUE.

Methods: Oat plants were subjected to the factorial combination of three soil moisture regimes (50, 70, and 90% of soil water holding capacity, SWHC) and three N levels (fertilized with 74, 149, and 298 mg kg−1).

Results: The stomatal conductance (gs) was significantly decreased by soil water deficit, and also by the highest N level, whereas photosynthesis rate (An) was unaffected by neither water nor N. Consequently, intrinsic WUE (WUEint, An/gs) was highest under reduced irrigation and high N fertilization. This effect at stomatal level was affirmed by responses in whole plant WUE (WUEb), which was positively correlated with shoot δ13C. A positive correlation between δ18O and δ13C in shoots further indicated that decreases of gs rather than changes in An contributed to the enhanced WUE.

Conclusion: Moderate soil water deficit and sufficient N supply is recommended for saving irrigation water and improving WUE on fertigated oat plants without compromising biomass accumulation to any large extent.
Two‐dimensional separation techniques using supercritical fluid chromatography
Authors: Kaplitz Alexander S. , Mostafa Mahmoud Elhusseiny , Calvez Samantha A. , Edwards James L. , Grinias James P.
Published: October 2020

High‐resolution separation systems are essential for the analysis of complex mixtures in a wide variety of application areas. To increase resolution, multidimensional chromatographic techniques have been one key solution. Supercritical fluid chromatography provides a unique opportunity in these multidimensional separations based on its potential for high solvent compatibility, rapid duty cycles, and orthogonality to other separation modes. This review focuses on two‐dimensional chromatography methods from the past decade that use supercritical fluid chromatography because of these advantages. Valving schemes and modulation strategies used to interface supercritical fluid chromatography with other liquid chromatography and gas chromatography techniques are described. Particular applications of multidimensional separations using supercritical fluid chromatography for the analysis of oils and chiral separations of pharmaceutical compounds are highlighted. Limitations of and a potential trajectory for supercritical fluid chromatography in this field are also discussed.
Character and environmental lability of cyanobacteria‐derived dissolved organic matter
Authors: Patriarca Claudia , Sedano‐Núñez Vicente T. , Garcia Sarahi L. , Bergquist Jonas , Bertilsson Stefan , Sjöberg Per J. R. , Tranvik Lars J. , Hawkes Jeffrey A.
Published: October 2020

Autotrophic dissolved organic matter (DOM) is central to the carbon biogeochemistry of aquatic systems, and the full complexity of autotrophic DOM has not been extensively studied, particularly by high‐resolution mass spectrometry (HRMS). Terrestrial DOM tends to dominate HRMS studies in freshwaters due to the propensity of such compounds to ionize by negative mode electrospray, and possibly also because ionizable DOM produced by autotrophy is decreased to low steady‐state concentrations by heterotrophic bacteria. In this study, we investigated the character of DOM produced by the widespread cyanobacteria Microcystis aeruginosa using high‐pressure liquid chromatography—electrospray ionization—high‐resolution mass spectrometry. M. aeruginosa produced thousands of detectable compounds in axenic culture. These compounds were chromatographically resolved and the majority were assigned to aliphatic formulas with a broad polarity range. We found that the DOM produced by M. aeruginosa was highly susceptible to removal by heterotrophic freshwater bacteria, supporting the hypothesis that this autotroph‐derived organic material is highly labile and accordingly only seen at low concentrations in natural settings.
NPC1 silent variant induces skipping of exon 11 (p.V562V) and unfolded protein response was found in a specific Niemann‐Pick type C patient
Authors: Encarnação Marisa , Coutinho Maria Francisca , Cho Soo Min , Cardoso Maria Teresa , Ribeiro Isaura , Chaves Paulo , Santos Juliana Inês , Quelhas Dulce , Lacerda Lúcia , Leão Teles Elisa , Futerman Anthony H. , Vilarinho Laura , Alves Sandra
Published: October 2020

Background

Niemann‐Pick type C (NPC, MIM #257220) is a neuro‐visceral disease, caused predominantly by pathogenic variants in the NPC1 gene. Here we studied patients with clinical diagnosis of NPC but inconclusive results regarding the molecular analysis.

Methods

We used a Next‐Generation Sequencing (NGS)‐panel followed by cDNA analysis. Latter, we used massively parallel single‐cell RNA‐seq (MARS‐Seq) to address gene profiling changes and finally the effect of different variants on the protein and cellular levels.

Results

We identified novel variants and cDNA analysis allowed us to establish the functional effect of a silent variant, previously reported as a polymorphism. We demonstrated that this variant induces the skipping of exon 11 leading to a premature stop codon and identified it in NPC patients from two unrelated families. MARS‐Seq analysis showed that a number of upregulated genes were related to the unfolded protein response (UPR) and endoplasmic reticulum (ER) stress in one specific patient. Also, for all analyzed variants, the NPC1 protein was partially retained in the ER.

Conclusion

We showed that the NPC1 silent polymorphism (p.V562V) is a disease‐causing variant in NPC and that the UPR is upregulated in an NPC patient.
Numerical solutions of distributed order fractional differential equations in the time domain using the Müntz–Legendre wavelets approach
Authors: Maleknejad Khosrow , Rashidinia Jalil , Eftekhari Tahereh
Published: October 2020

In this paper, a numerical method is presented to obtain and analyze the behavior of numerical solutions of distributed order fractional differential equations of the general form in the time domain with the Caputo fractional derivative. The suggested method is based on the Müntz–Legendre wavelet approximation. We derive a new operational vector for the Riemann–Liouville fractional integral of the Müntz–Legendre wavelets by using the Laplace transform method. Applying this operational vector and collocation method in our approach, the problem can be reduced to a system of linear and nonlinear algebraic equations. The arising system can be solved by the Newton method. Discussion on the error bound and convergence analysis for the proposed method is presented. Finally, seven test problems are considered to compare our results with other well‐known methods used for solving these problems. The results in the tabulated tables highlighted that the proposed method is an efficient mathematical tool for analyzing distributed order fractional differential equations of the general form.
A sixth‐order improved Runge–Kutta direct method for special third‐order ordinary differential equations
Authors: Ökten Turacı Mukaddes , Özdemir Merve
Published: October 2020

In this paper, we construct a four‐stage explicit improved Runge–Kutta direct (IRKD) method of order six for solving special third‐order ordinary differential equations. The sixth‐order IRKD method is a two‐step method and it requires fewer number of stages compared to the classical Runge–Kutta method of the same order per step. The stability properties of the proposed method are given. Numerical results are presented to demonstrate the efficiency and accuracy of the proposed method compared with the existing methods in the literature.
A National‐Level Informational Experiment to Promote Enrollment in Selective Colleges
Authors: Gurantz Oded , Howell Jessica , Hurwitz Michael , Larson Cassandra , Pender Matea , White Brooke
Published: October 2020

Prior research finds that low‐income students are less likely to apply to and enroll in four‐year colleges or more selective colleges, even after controlling for academic preparation and other background characteristics. The College Board sought to reduce barriers in the college application process through a targeted campaign of brochures and e‐mails. These materials were sent to students two to three times between the end of eleventh grade and the middle of twelfth grade, and aimed to provide an impetus to start the college search process, minimize the costs of aggregating data, and encourage a broader college application portfolio. Some students were offered additional encouragements, such as text message reminders or college application fee waivers. In a randomized control trial with 785,000 low‐ and middle‐income students in the top 50 percent of the PSAT and SAT distributions, we find no changes in college enrollment patterns.
Complementary Use of U.S. FDA’s Adverse Event Reporting System and Sentinel System to Characterize Direct Oral Anticoagulants‐Associated Cutaneous Small Vessel Vasculitis
Authors: Mohamoud Mohamed , Horgan Casie , Eworuke Efe , Dee Elizabeth , Bohn Justin , Shapira Oren , Munoz Monica A. , Stojanovic Danijela , Sansing‐Foster Veronica , Ajao Adebola , La Grenade Lois
Published: October 2020

Background

Cutaneous small vessel vasculitis (CSVV) has been reported after exposure to direct oral anticoagulants (DOACs), such as dabigatran, rivaroxaban, apixaban, and edoxaban.

Objective

We used the U.S. Food and Drug Administration Adverse Event Reporting System (FAERS) to describe clinical characteristics associated with CSVV among DOAC‐exposed patients. Furthermore, we characterized this signal in the Sentinel System to relate the clinical data from the individual FAERS cases to population‐based electronic healthcare data.

Methods

We queried FAERS for all cases of CSVV associated with DOACs from U.S. approval date of each DOAC through March 16, 2018. Within the Sentinel System, we identified incident CSVV cases using ICD‐9 and ICD‐10 diagnosis codes among adults aged ≥ 30 years who received a DOAC in the prior 90 days between January 1, 2010, and June 30, 2018. We excluded patients with evidence of select autoimmune diagnoses in the 183 days prior to their CSVV diagnoses and reported patient characteristics in the 183‐day period prior to CSVV diagnoses.

Results

In FAERS, we identified 50 cases of CSVV reported with rivaroxaban (n=26), apixaban (n=14), dabigatran (n=9), and edoxaban (n=1). Approximately 50% of the cases reported time to onset within 10 days after DOAC exposure. When specified, the predominant type of CSVV reported was leukocytoclastic vasculitis (n=31), followed by Henoch‐Schonlein purpura (n=4). Hospitalization occurred in most of the cases (n=37). Switching of the offending agent after the development of CSVV was reported (n=26). Three rivaroxaban (n=3) cases and one dabigatran case (n=1) reported positive rechallenge. In the Sentinel system, we identified 3659 CSVV cases with prior DOAC exposure, with 85% of events occurring within 10 days.

Conclusions

The assessment of FAERS cases, combined with the temporal clustering of the Sentinel System cases suggest a possible causal relationship of DOACs and CSVV. Future efforts should characterize the risk of CSVV among the various DOAC users.
Characterization of field‐evolved resistance to pyridalyl in a near‐isogenic line of diamondback moth, Plutella xylostella
Authors: Wang Ran , Fang Yong , Zhang Jiasong , Wang Jinda , Feng Honglin , Luo Chen
Published: October 2020

BACKGROUND

Plutella xylostella has developed resistance to a variety of pesticides in the field. Selection, inheritance, a near‐isogenic line, cross‐resistance and biochemical mechanisms of pyridalyl resistance were characterized in a field‐collected resistant population of P. xylostella from China.

RESULTS

Compared with a susceptible IVF‐S strain, the field‐collected FZ population showed ~ 350‐fold resistance to pyridalyl. The FZ‐PY strain, selected from the FZ population using pyridalyl, developed ~ 640‐fold resistance to pyridalyl. Inheritance tests indicated that pyridalyl resistance in the FZ‐PY strain was autosomal and incompletely recessive. Through successive backcrossing to IVF‐S, a near‐isogenic strain (NIL‐PY) was established that exhibited 191.21‐fold resistance to pyridalyl and no cross‐resistance to other tested popular insecticides. No significant effects of synergists and higher activities of metabolic enzymes were observed in NIL‐PY compared with IVF‐S. Furthermore, the survival rate of NIL‐PY larvae, and female oviposition, fecundity and egg viability were markedly reduced in NIL‐PY compared with IVF‐S. The fitness of NIL‐PY was found to be 0.56 compared with IVF‐S.

CONCLUSION

Considering that no relevant effects of synergists or oxidative metabolism were observed in NIL‐PY, and that pyridalyl resistance results in significant fitness costs compared with IVF‐S, further research will be conducted on the mechanism of target‐site resistance. © 2020 Society of Chemical Industry
Characterization of the binding ability of the odorant binding protein BminOBP9 of Bactrocera minax to citrus volatiles
Authors: Yao Runxian , Zhao Mingming , Zhong Ling , Li Yi , Li Dazhi , Deng Ziniu , Ma Xianfeng
Published: October 2020

BACKGROUND

Bactrocera minax, one of the most important citrus pests, oviposits exclusively on citrus fruit. In the insect olfactory system, odorant‐binding proteins (OBPs) facilitate the initial recognition role of host odor molecules. The aim of this study was to characterize the functional OBPs of B. minax and identify specific volatile organic compounds in the Citrus genus as OBP targets.

RESULTS

BminOBP9 (BminGOBP99a), a closely related homolog of BdorGOBP99a, which reduces the egg‐laying behavior of Bactrocera dorsalis through silencing technology, was cloned, expressed, and purified. The binding ability of BminOBP9 to 11 citrus volatiles was then examined using fluorescence competition binding assays (FCBA). The results demonstrated that BminOBP9 could bind to all tested citrus volatiles, as could BdorGOBP99a, ZcucGOBP99a, and ZtauGOBP99a. Interestingly, the binding ability of BminOBP9 was the strongest among the four, suggesting that BminOBP9 may have a function in the specific recognition of citrus volatiles. Furthermore, we aligned the above four proteins and found nine distinctive amino acid sites in BminOBP9. To identify the unique binding sites of BminOBP9, we produced the nine mutants using site‐directed mutagenesis. Further FCBA showed that the binding ability of the nine mutants to citrus volatiles significantly reduced, and six of them (substitutes S24P, L36F, E53K, N68D, D112A, and S118R) had the weakest binding ability.

CONCLUSION

The results demonstrated that BminOBP9 was the specific protein involved in the perception of citrus host volatiles by B. minax. Moreover, BminOBP9 could prove efficient in screening the candidate odors for pest management. © 2020 Society of Chemical Industry
Optical–Microwave Pump–Probe Studies of Electronic Properties in Novel Materials
Authors: Kollarics Sándor , Bojtor András , Koltai Kristóf , Márkus Bence Gábor , Holczer Károly , Volk János , Klujber Gergely , Szieberth Máté , Simon Ferenc
Published: October 2020

Combined microwave–optical pump–probe methods are emerging to study the quantum state of spin qubit centers and the charge dynamics in semiconductors. A major hindrance is the limited bandwidth of microwave irradiation/detection circuitry which can be overcome with the use of broadband coplanar waveguides (CPWs). The development and performance characterization of two spectrometers is presented as follows: an optically detected magnetic resonance spectrometer (ODMR) and a microwave‐detected photoconductivity measurement. In the first method, light serves as detection and microwaves excite the investigated medium, whereas in the second, the roles are interchanged. The performance is demonstrated by measuring ODMR maps on the nitrogen‐vacancy (NV) center in diamond and time‐resolved photoconductivity in p‐doped silicon. The results demonstrate both an efficient coupling of the microwave irradiation to the samples as well as an excellent sensitivity for minute changes in sample conductivity.
A role for quercetin in coronavirus disease 2019 (COVID‐19)
Authors: Derosa Giuseppe , Maffioli Pamela , D'Angelo Angela , Di Pierro Francesco
Published: October 2020

Several months ago, an outbreak of pneumonia of unknown aetiology was detected in Wuhan City (China) and the aetiological agent of the atypical pneumonia was isolated by the Chinese authorities as novel coronavirus (2019‐nCoV or SARS‐CoV‐2). The WHO announced this new disease was to be known as “COVID‐19.” When looking for new antiviral compounds, knowledge of the main viral proteins is fundamental. The major druggable targets of SARS‐CoV‐2 include 3‐chymotrypsin‐like protease (3CLpro), papain‐like protease (PLpro), RNA‐dependent RNA polymerase, and spike (S) protein. Quercetin inhibits 3CLpro and PLpro with a docking binding energy corresponding to −6.25 and −4.62 kcal/mol, respectively. Quercetin has a theoretical, but significant, capability to interfere with SARS‐CoV‐2 replication, with the results showing this to be the fifth best compound out of 18 candidates. On the basis of the clinical COVID‐19 manifestations, the multifaceted aspect of quercetin as both antiinflammatory and thrombin‐inhibitory actions, should be taken into consideration.
Anti‐inflammatory effects of cordycepin: A review
Authors: Tan Lu , Song Xiaominting , Ren Yali , Wang Miao , Guo Chuanjie , Guo Dale , Gu Yucheng , Li Yuzhi , Cao Zhixing , Deng Yun
Published: October 2020

Cordycepin is the major bioactive component extracted from Cordyceps militaris. In recent years, cordycepin has received increasing attention owing to its multiple pharmacological activities. This study reviews recent researches on the anti‐inflammatory effects and the related activities of cordycepin. The results from our review indicate that cordycepin exerts protective effects against inflammatory injury for many diseases including acute lung injury (ALI), asthma, rheumatoid arthritis, Parkinson's disease (PD), hepatitis, atherosclerosis, and atopic dermatitis. Cordycepin regulates the NF‐κB, RIP2/Caspase‐1, Akt/GSK‐3β/p70S6K, TGF‐β/Smads, and Nrf2/HO‐1 signaling pathways among others. Several studies focusing on cordycepin derivatives were reviewed and found to down metabolic velocity of cordycepin and increase its bioavailability. Moreover, cordycepin enhanced immunity, inhibited the proliferation of viral RNA, and suppressed cytokine storms, thereby suggesting its potential to treat COVID‐19 and other viral infections. From the collected and reviewed information, this article provides the theoretical basis for the clinical applications of cordycepin and discusses the path for future studies focusing on expanding the medicinal use of cordycepin. Taken together, cordycepin and its analogs show great potential as the next new class of anti‐inflammatory agents.
Sustainability assessment framework and indicators developed by SuRF‐UK for land remediation option appraisal
Authors: Bardos R. Paul , Thomas Hayley F. , Smith Jonathan W. N. , Harries Nicola D. , Evans Frank , Boyle Richard , Howard Trevor , Lewis Richard , Thomas Alan O. , Dent Vivien L. , Haslam Angela
Published: October 2020

The scale of land‐contamination problems, and of the responses to them, makes achieving sustainability in contaminated land remediation an important objective. The Sustainable Remediation Forum in the UK (SuRF‐UK) was established in 2007 to support more sustainable remediation practices in the UK. The prevailing international consensus is that risk assessment is the most rational approach for determining remediation needs and urgency. Sustainability in this context is related to the effective delivery of whatever risk management is necessary to protect human health or the wider environment. SuRF‐UK suggests that decisions made at the project planning stage, and also in the choice of remediation approach used to reach particular objectives decided upon, are both opportunities for sustainability gain. In 2011, SuRF‐UK issued a set of wide‐ranging indicators to support sustainability assessments made during project planning and remediation option appraisal. This advice was reviewed over 2018–2020 and new guidance on process and indicators has been released. Within this guidance, SuRF‐UK has provided a checklist of possible sustainability indicators/criteria that can be used to benchmark the scope of sustainability assessment for remediation projects. These indicators are divided into 15 overarching (“headline”) categories, divided in a balanced way across the three elements of sustainability: Environmental (emissions to air, soil and ground conditions, groundwater and surface water, ecology, and natural resources and waste); social (human health and safety, ethics and equity, neighborhoods and locality, communities and community involvement, and uncertainty and evidence); and economic (direct economic costs and benefits, indirect economic costs and benefits, employment and employment capital, induced economic costs and benefits, and project lifespan and flexibility). The majority of this study explains these categories and their various considerations in more depth and provides the supporting rationale that led to their inclusion in the revised SuRF‐UK guidance.
Chattering analysis for Lipschitz continuous sliding‐mode controllers
Authors: Martínez‐Fuentes Carlos Arturo , Pérez‐Ventura Ulises , Fridman Leonid
Published: October 2020

In this article, an analysis of chattering in systems driven by Lipschitz continuous sliding‐mode controllers (LCSMC) is performed using the describing function approach. Two kinds of LCSMC are considered: the first one is based on a linear sliding variable (LSV) and the second one on a terminal sliding variable (TSV). Predictions of amplitude, frequency, and average power of self‐excited oscillations, are used to compare such LCSMC respect to the supertwisting controller (STC) in systems with fast‐actuators. Theoretical predictions and simulations allow the following conclusions: (i) LCSMC still may induce fast‐oscillations (chattering) of smaller amplitude and average power, than ones caused by the STC in the absence of the measurement noises. (ii) The level of chattering with LSV‐LCSMC could be smaller than one produced by TSV‐LCSMC. (iii) The zero (sliding) dynamics of the LSV‐LCSMC cannot be arbitrarily fast or the closed‐loop system may lose even practical stability, unlike the TSV‐LCSMC whose trajectories are finally bounded.
Reaction wheel pendulum control using fourth‐order discontinuous integral algorithm
Authors: Gutiérrez‐Oribio Diego , Mercado‐Uribe Ángel , Moreno Jaime A. , Fridman Leonid
Published: October 2020

The fourth‐order model of the reaction wheel pendulum is considered and a fourth‐order discontinuous integral algorithm is used for stabilization and tracking of the system, using a continuous control signal. The states reach the origin or a reference signal in finite‐time, even in presence of uncertain control coefficient and a kind of matched and unmatched uncertainties/disturbances. A homogeneous Lyapunov function is designed to ensure local finite‐time stability of the system, which can be used for designing the controller gains. Simulations and experimental results illustrate the performance and advantages of the presented algorithm.
Physicochemical Comparison of Chitin Extracted from Horseshoe Crab (Limulus polyphemus) Exoskeleton and Exuviae
Authors: Mendez‐Alpuche A. A. , Ríos‐Soberanis C. R. , Rodriguez‐Laviada J. , Perez‐Pacheco E. , Zaldivar‐Rae J. A.
Published: October 2020

In this paper, horseshoe crab exoskeleton and exuviae were collected on the coasts of Yucatan and physicochemical studies were carried out. Samples from different sections of the exoskeleton were taken to evaluate chitin content and properties in order to be compared with exuviae. The isolation of chitin was realized by chemical processes involving deproteinization, demineralization and discoloration. Physicochemical properties of chitin extracted from both sources were compared in terms of characterization analysis in particular achieved under EDX, FTIR and calorimetric techniques (DSC and TGA). In such comparative analysis lies the importance to establish differences or similitudes in chitin contents, structure, etc. Scanning Electron Microcopy was conducted on exuviae and exoskeleton selected parts in order to identify horseshoe crab structure and surface morphology. Differential scanning calorimetry was focused on changes in physical and chemical structures at different samples showing two endothermic peaks related to the complete elimination of hydroxyl groups attached to polysaccharide rings. TGA thermograms were characterized by endo and exotherms corresponding to water evaporation and decomposition of polymer respectively. Exoskeleton SEM images shown a tubular network and porous surface while exuviae exhibited irregular surface and diatom unicellular microalgae embedded. Calorimetric measurements confirmed that exuviae is richer in chitin than exoskeleton and that the main allotropic crystal structure corresponds to α‐chitin. FTIR analysis supported these results by exhibiting different absorption bands corresponding to α‐chitin.
Kaurenoic Acid Induces Cell Cycle Arrest and Apoptosis in the MCF‐7 Breast Cancer Cell Line
Authors: Roberto de Souza Anderson , Stefany de Souza Castro Mona , Olímpio de Souza Thiago , Cassio Sola Veneziani Rodrigo , Kenupp Bastos Jairo , Ricardo Ambrósio Sérgio , Alves dos Santos Raquel
Published: October 2020

Breast cancer continues to be the major cause of cancer death among women. The high genetic heterogeneity and chemoresistant phenotypes of breast tumors require the search for new compounds to expand the options for the treatment of this disease. Kaurenoic acid (KA) is an ent‐kaurane type‐diterpene with cytotoxic and genotoxic effects against gastric and cervical cancer cells. In the present study, we report the antiproliferative effects of KA in the breast tumoral cell line MCF‐7 and the normal breast counterpart MCF‐10 A. The long‐term cytotoxic effects of KA were observed by the reduction of survival fraction at 50 and 100 μM. At these concentrations, the treatment with KA increased the extension of DNA damage followed by G1 cell cycle phase accumulation and induction of apoptosis in both cell lines. Taken together, the results contained herein support the promising antiproliferative effects of KA.
One‐step Preparation of Conducting Polymer/Metal Oxide Doped RGO Trinary Composite for Supercapacitor Applications
Authors: Wadekar Pravin H. , Khose Rahul V. , Pethsangave Dattatray A. , Some Surajit
Published: October 2020

A naive one‐pot strategy developed to prepare high‐performance trinary based material as an energy storage material for supercapacitor. Herein, we have systematically studied and established an effortless and proficient synthetic method to formulate reduced graphene oxide (rGO)/polyaniline (PANI)/manganese dioxide (MnO2) (RPM) trinary material in one‐step without any additional oxidizing/polymerizing agent and acidic condition. The approach of “one arrow two targets” have employed to synthesize trinary based nanocomposite. For the first time, we have synthesized this trinary material in one step. Initially, in‐situ synthesized carbonic acid was consumed as a reducing agent to reduce the graphene oxide (GO) as well as it provided acidic condition for the formation of MnO2 and polymerization of aniline. Secondarily, MnO2 particles synthesized from KMnO4 precursor, which acted as an oxidizing agent to polymerize aniline in the presence of carbonic acid. The material reflected the electrical double layer capacitance as well as pseudocapacitance of RGO and PANI/MnO2. The material exhibited the maximum specific capacitance, 592 F/g at 1 A/g current density corresponds to excessive specific energy and specific power 66.6 Wh/kg, 1800 W/kg, respectively. This familiar route of direct production of graphene with the synergism of PANI‐MnO2 on carbon can be useful for large‐scale fabrication of nano‐carbon material for diverse applications including energy storage application.
Improved In Vitro Antimycobacterial Activity of Trinuclear Complexes Cobalt(II,III) and Iron(III) with 2‐Furoic Acid againstMycolicibacterium smegmatis
Authors: Lutsenko Irina A. , Yambulatov Dmitriy S. , Kiskin Mikhail A. , Nelyubina Yulia V. , Primakov Petr V. , Bekker Olga B. , Levitskiy Oleg A. , Magdesieva Tatiana V. , Imshennik Vladimir K. , Maksimov Yurii V. , Sidorov Aleksey A. , Danilenko Valery N. , Eremenko Igor L.
Published: October 2020

The reaction of cobalt(II) and iron(III) pivalates with anions of 2‐furancarboxylic acid (pyromucic acid, Hfur) yielded trinuclear homometallic complexes with linear ([Co3(fur)6(phen)2] (1, phen=1,10‐phenanthroline)) and triangular ([Co3O(fur)6(H2O)3] (3), [Fe3O(fur)6(THF)3] ⋅ 3THF (4)) structures of the metal moiety. The hexanuclear mixed carboxylate cobalt complex [Co6(piv)8(Hpiv)4(fur)2(OH)2] (2, piv−=(CH3)3COO−) was isolated as an intermediate in the synthesis of3. According to CVA data, complex3contains bivalent and trivalent cobalt ions. According to Mossbauer spectroscopy data, all the iron(III) atoms in4, which is an isostructural analogue of3, are solely in the high‐spin state. The antibacterial activity of compounds1–4, K(fur) (5) and Na(fur) (6) was determined in vitro against a non‐pathogenicMycolicibacterium smegmatisstrain. The results of in vitro biological tests againstMycolicibacterium smegmatisshowed a high bioactivity of complexes1and4.
Asymmetric Hydrogenation of Acetophenone Catalyzed by Chirally Modified Ruthenium Nanoparticles Supported on Carbon Nanotubes
Authors: Lv Bolin , Lei Chen , Ren Fupeng , Wang Mingming , Hua Fenglin , Meng Shuangyan , Yang Yaoxia , Yang Zhiwang , Lei Ziqiang
Published: October 2020

Different types of carbon nanotubes as carriers were used to prepare ruthenium nano‐catalysts loaded outside (named as Ru/CNTs) and inside (named as Ru@CNTs) the tube. The catalysts were modified in situ with chiral ligands (1S, 2S)‐DPEN (1S, 2S)‐DPEN=(1S, 2S)‐1,2‐diphenyl‐1,2‐ethanediamine). In the presence of TPP (TPP=triphenylphosphine) as the stabilization, the catalytic asymmetric hydrogenation of acetophenone was carried out with the modified catalysts. A novel approach to prepare the inside‐loaded catalysts of Ru@CNTs was explored in the preparation. The catalyst can efficiently prevent the Ru nanoparticles from oxidizing in the air in this approach. The catalysts were well characterized by means of TEM, XRD, XPS, BET and H2 Pulse Chemisorption. The effect of the diameter of carbon nanotubes on the particle size of ruthenium nanoparticles loaded on the tubes was also well studied. When Ru@CNTs (8 %, S) (“S” abbreviated from “short”, the same below) was used in the asymmetric hydrogenation of acetophenone, 100 % conversion of acetophenone achieved, and the ee value reached 76.4 %. Under the same reaction conditions, 100 % conversion of acetophenone as well as the highest ee value of 80.8 % were obtained when Ru/CNTs (8 %, S) was applied in the reaction.
Studies Towards the Synthesis of Pristinamycin IIA
Authors: Sušnik Peter , Koert Ulrich
Published: October 2020

Studies towards a total synthesis of pristinamycin IIA (1) as part of group A streptogramins is described. Stereoselective syntheses of three building blocks A, B and C including the 2,3‐dehydroproline substructure and their assembly into advanced CAB‐precursor molecules for the natural product was achieved. Attempts to close the macrocylic ring at a late stage by Sm2/Barbier or Nozaki‐Hiyama‐Takai‐Kishi‐reaction demonstrate challenges and limitations of this approach.
Non‐Equilibrium Synthesis of Highly Active Nanostructured, Oxygen‐Incorporated Amorphous Molybdenum Sulfide HER Electrocatalyst
Authors: Giuffredi Giorgio , Mezzetti Alessandro , Perego Andrea , Mazzolini Piero , Prato Mirko , Fumagalli Francesco , Lin Yu‐Chuan , Liu Chenze , Ivanov Ilia N. , Belianinov Alex , Colombo Massimo , Divitini Giorgio , Ducati Caterina , Duscher Gerd , Puretzky Alexander A. , Geohegan David B. , Di Fonzo Fabio
Published: October 2020

Molybdenum sulfide emerged as promising hydrogen evolution reaction (HER) electrocatalyst thanks to its high intrinsic activity, however its limited active sites exposure and low conductivity hamper its performance. To address these drawbacks, the non‐equilibrium nature of pulsed laser deposition (PLD) is exploited to synthesize self‐supported hierarchical nanoarchitectures by gas phase nucleation and sequential attachment of defective molybdenum sulfide clusters. The physics of the process are studied by in situ diagnostics and correlated to the properties of the resulting electrocatalyst. The as‐synthesized architectures have a disordered nanocrystalline structure, with nanodomains of bent, defective S‐Mo‐S layers embedded in an amorphous matrix, with excess sulfur and segregated molybdenum particles. Oxygen incorporation in this structure fosters the creation of amorphous oxide/oxysulfide nanophases with high electrical conductivity, enabling fast electron transfer to the active sites. The combined effect of the nanocrystalline pristine structure and the surface oxidation enhances the performance leading to small overpotentials, very fast kinetics (35.1 mV dec−1 Tafel slope) and remarkable long‐term stability for continuous operation up to ‐1 A cm−2. This work shows possible new avenues in catalytic design arising from a non‐equilibrium technique as PLD and the importance of structural and chemical control to improve the HER performance of MoS‐based catalysts.
Recent Progress of Organic Solar Cells with Insulating Polymers
Authors: Wang Tong , Liu Jian-Qiang , Hao Xiao-Tao
Published: October 2020

Organic solar cells (OSCs), as a promising photovoltaic technology, have made great progress recently due to the various optimization methods and designs of new materials. However, the general strategies show some restrictions on photovoltaic systems and commercialization of OSCs. Insulating polymers with low costs exhibit rich functionality, enhance device performance, and stabilize film morphology in air or at a high temperature. Herein, the strategies of the ternary, interface layer, and block copolymer in insulator‐modified OSCs (i‐OSCs) reported in recent years are highlighted. In addition, the corresponding underlying mechanisms, such as crystallinity, self‐assembly, dipole interaction, and charge transfer, are also discussed. The applications of insulating polymers in OSCs open a novel avenue for optimizing device performance and bestow a potential pathway to achieve large‐scale industrial production in the future.
Numerical Estimation of the Geometry and Temperature of An Alternating Current Steelmaking Electric Arc
Authors: Hernández Jesús D. , Onofri Luca , Engell Sebastian
Published: October 2020

A channel arc model (CAM) that predicts the temperature and the geometry of an electric arc from its voltage and impedance set‐points is presented. The core of the model is a nonlinear programming (NLP) formulation that minimizes the entropy production of a plasma column, the physical and electrical properties of which satisfy the Elenbaas–Heller equation and Ohm's law. The radiative properties of the plasma are approximated utilizing the net emission coefficient (NEC), and the NLP is solved using a global numerical solver. The effects of the voltage and impedance set‐points on the length of the electric arc are studied, and a linear formula that estimates the length of the arc in terms of its electrical set‐points is deducted. The length of various electric arcs is measured in a fully operative electric arc furnace (EAF), and the results are used to validate the proposed models. The errors in the predictions of the models are 0.5 and 0.4 cm. In comparison, the existing empirical and Bowman formulae estimate the length of the experimental arcs with errors of 2.1 and 2.6 cm. A simplified formula to estimate the temperature of an electric arc in terms of its electrical set‐points is also presented.
Defective Structures in Metal Compounds for Energy‐Related Electrocatalysis
Authors: Yan Xuecheng , Jia Yi , Yao Xiangdong
Published: October 2020

Catalysts play a critical role in accelerating the electrochemical reactions. Engineering the electronic structures and surface properties of electrocatalysts is a feasible approach to improve their catalytic performance. Introducing defects such as anion and cation vacancies into transition metal‐based materials to enhance their activity for various energy‐related electrocatalytic reactions has been receiving increasingly attention in recent years. In this review, a systematic summary of the anion and cation defects on different electrochemical reactions will be presented. In particular, the commonly used methods to produce anion vacancies (such as oxygen, sulfur, and phosphorus defects) and cation vacancies (such as Fe, Co, and Ni defects) will be discussed. The control of the defect density and refilling heteroatoms to stabilize the anion defects and simultaneously to further enhance their catalytic performance are also summarized. In addition, recent work on creating multivacancies in transition metal‐based electrocatalysts for maximizing their catalytic activities is reviewed as well. Finally, future research on defect engineering in metal compounds for electrocatalysis is proposed. This review will guide the further development of various energy‐related electrocatalytic reactions promoted by defective structures in metal composites.
Functional Liquid Crystal Polymer Surfaces with Switchable Topographies
Authors: Feng Wei , Liu Danqing , Broer Dirk J.
Published: October 2020

Surface coatings, as interfaces between functional devices and targeted objects, are critical in the performance of functional devices. Switchable topographies bring opportunities to regulate the functionality of surfaces, ranging from morphing and controllable friction to object lifting and debris removal. Various responsive materials have been investigated to develop switchable surfaces, among which liquid crystal (LC) polymers are attractive candidates due to their anisotropic properties. Herein, focus is put on recent reports of switchable surfaces made of LC polymers. The principle of actuation of LC polymer–based switchable surfaces is introduced, with following exemplary applications derived from these responsive surfaces in the field of surface morphing, switchable surface friction, and moving/lifting of objects. Finally, future possible applications of and challenges in using dynamic coatings with switchable surface topographies are discussed.