bluuebunny/crossref_metadata_2025 huggingface dataset:
Primary metabolites from overproducing microbial system using sustainable substrates
Authors: Srivastava Rajesh K. , Akhtar Nasim , Verma Malkhey , Imandi Sarat Babu
Published: April 2020

Primary (or secondary) metabolites are produced by animals, plants, or microbial cell systems either intracellularly or extracellularly. Production capabilities of microbial cell systems for many types of primary metabolites have been exploited at a commercial scale. But the high production cost of metabolites is a big challenge for most of the bioprocess industries and commercial production needs to be achieved. This issue can be solved to some extent by screening and developing the engineered microbial systems via reconstruction of the genome‐scale metabolic model. The predicted genetic modification is applied for an increased flux in biosynthesis pathways toward the desired product. Wherein the resulting microbial strain is capable of converting a large amount of carbon substrate to the expected product with minimum by‐product formation in the optimal operating conditions. Metabolic engineering efforts have also resulted in significant improvement of metabolite yields, depending on the nature of the products, microbial cell factory modification, and the types of substrate used. The objective of this review is to comprehend the state of art for the production of various primary metabolites by microbial strains system, focusing on the selection of efficient strain and genetic or pathway modifications, applied during strain engineering.
Lithotripsy for peripheral artery disease: Encouraging immediate results…But show us the money!
Authors: Hering Dagmara , Heuser Richard R.
Published: April 2020

Key Points

Of adults, 12% have PAD, with nearly 30% older than 70 years with the disorder.

With obesity, diabetes mellitus, tobacco abuse, hypercholesterolemia, and poorly controlled hypertension, the incidence of PAD continues to increase.

Endovascular treatment of femoropopliteal disease has an alarmingly high rate of restenosis, even with new technology with target lesion revascularization rates at 40–60% at 1 year.

Intravascular lithotripsy appears to be safe and acutely effective, but there is no long‐term data on whether it has a role in effective treatment of PAD.
Diastolic dysfunction in severe aortic stenosis: Old but still gold
Authors: Perrino Cinzia , Esposito Giovanni
Published: April 2020

Key Points

A simple, widely applicable and reproducible risk predictor may improve patient care, risk stratification, and clinical decision making for symptomatic severe aortic stenosis (sAS) patients undergoing transcatheter aortic valve implantation (TAVI).

Baseline severe left ventricular diastolic dysfunction identified by E/A ratio in sAS patients undergoing TAVI is associated with increased post‐procedural all‐cause mortality or heart failure hospitalization but is not an independent predictor of outcome.

Large studies employing multimodality imaging of cardiac function/structure and accounting for sex and comorbidities will be necessary to validate DD parameters (or their combination) in sAS patients undergoing TAVI.
Not to worry (most of the time)
Authors: Hagler Donald J.
Published: April 2020

Key Points

Most (87.6%) of residual atrial L‐R shunts after Gore Cardioform septal occluder implant disappear by 12 months.

Residual leaks at implantation were more common in larger defects with smaller retro‐aortic rims, and multiple fenestrations.

While most residual defects close in 12 months, we unfortunately do not yet have a clear idea why or which of the 13% do not close.
Does the method of administering fluids matter for contrast‐induced nephropathy? REMEDIAL III compares LVEDP versus urine flow‐guided hydration
Authors: Grines Cindy L. , Marshall J. Jeffrey
Published: April 2020

Key Points

Contrast‐induced nephropathy (CIN) is a major cause of morbidity and mortality among patients undergoing angiographic procedures.

Limiting contrast dose and administration of intravenous normal saline appear to be the best approaches to reducing CIN, but the timing, dose, and duration of optimal hydration is poorly understood.

The REMEDIAL III trial protocol outlines two different targeted hydration regimens (guided either by continuous measurement of urine output or by initial left ventricular end diastolic pressure (LVEDP), and 700 patients at high risk of CIN will be randomized.
Editorial on coronary artery fistulae
Authors: Tobis Jonathan M.
Published: April 2020

Key Points

Over 21 years, 26 coronary artery fistulae were treated percutaneously, and 21 (81%) were successful.

There is still much to be learned about the physiology of coronary fistulae.

Transcatheter methods have improved over the years and permit a high success rate, but some cases still require a surgical approach.
Preclinical comparative assessment of a dedicated pediatric poly‐L‐lactic‐acid‐based bioresorbable scaffold with a low‐profile bare metal stent
Authors: Shibbani Kamel , De Lima e Silva Bagno Luiza , Poulin Marie‐France , Matella Thomas , Diab Karim , Kavinsky Clifford , Ramesh Nagarajan , Bhat Vinayak , Hijazi Ziyad M. , Kenny Damien
Published: April 2020

Background

Polymer‐based bioresorbable scaffolds (PBBS) have been assessed for coronary revascularization with mixed outcomes. Few studies have targeted pediatric‐specific scaffolds. We sought to assess safety, efficacy, and short‐term performance of a dedicated drug‐free PBBS pediatric scaffold compared to a standard low‐profile bare metal stent (BMS) in central and peripheral arteries of weaned piglets.

Methods

Forty‐two devices (22 Elixir poly‐L‐lactic‐acid‐based pediatric bioresorbable scaffolds [BRS] [6 × 18 mm] and 20 control BMS Cook Formula 418 [6 × 20 mm]) were implanted in the descending aorta and pulmonary arteries (PAs) of 14 female Yucatan piglets. Quantitative measurements were collected on the day of device deployment and 30 and 90 days postimplantation to compare device patency and integrity.

Results

The BRS has a comparable safety profile to the BMS in the acute setting. Late lumen loss (LLL) and percent diameter stenosis (%DS) were not significantly different between BRS and BMS in the PA at 30 days. LLL and %DS were greater for BRS versus BMS in the aorta at 30 days postimplantation (LLL difference: 0.96 ± 0.26; %DS difference: 16.15 ± 4.51; p < .05). At 90 days, %DS in the aortic BRS was less, and PA BRS LLL was also less than BMS. Histomorphometric data showed greater intimal proliferation and area stenosis in the BRS at all time points and in all vessels.

Conclusions

A dedicated PBBS pediatric BRS has a favorable safety profile in the acute/subacute setting and demonstrates characteristics that are consistent with adult BRSs.
Cotton Cloth‐Induced Flexible Hierarchical Carbon Film for Sodium‐Ion Batteries
Authors: Zhang Xixue , Wan Yanhua , Yang Kaiwei , Song Keming , Mi Liwei , Zheng Guoqiang , Feng Xiangming , Chen Weihua
Published: April 2020

Flexible substrates play a decisive effect on the functions of flexible energy storage devices. However, systematical investigation and understanding of often‐used flexible carbon‐based substrates is lack. In this work, a reliable cotton cloth induced flexible hierarchical carbon film is facilely obtained. The synthesized‐carbonized cotton cloth (SCC) owns distinctive carbon nature with perfect order level and defects, unique porous microstructure, and crosslinked‐network. The SCC exhibits favorable flexibility, fast kinetics, high structural and electrochemical durability with high performance (239.4 mAh g−1 and 155.2 mAh g−1 at 0.01 A g−1 in the ether‐ and ester‐based electrolyte in sodium‐ion batteries, respectively), superior to commonly‐used commercial carbon cloth and graphene film. In addition, the predominant surface‐controlled reaction mechanism, effective solid electrolyte interphase and favorable compatible features with different electrolytes are also intensively studied.
Heavy‐Atom Tunneling in Semibullvalenes: How Driving Force, Substituents, and Environment Influence the Tunneling Rates
Authors: Schleif Tim , Tatchen Jörg , Rowen Julien F. , Beyer Frederike , Sanchez‐Garcia Elsa , Sander Wolfram
Published: April 2020

The Cope rearrangement of selectively deuterated isotopomers of 1,5‐dimethylsemibullvalene 2 a and 3,7‐dicyano‐1,5‐dimethylsemibullvalene 2 b were studied in cryogenic matrices. In both semibullvalenes the Cope rearrangement is governed by heavy‐atom tunneling. The driving force for the rearrangements is the small difference in the zero‐point vibrational energies of the isotopomers. To evaluate the effect of the driving force on the tunneling probability in 2 a and 2 b, two different pairs of isotopomers were studied for each of the semibullvalenes. The reaction rates for the rearrangement of 2 b in cryogenic matrices were found to be smaller than the ones of 2 a under similar conditions, whereas differences in the driving force do not influence the rates. Small curvature tunneling (SCT) calculations suggest that the reduced tunneling rate of 2 b compared to that of 2 a results from a change in the shape of the potential energy barrier. The tunneling probability of the semibullvalenes strongly depends on the matrix environment; however, for 2 a in a qualitatively different way than for 2 b.
Electroactive Organic Building Blocks for the Chemical Design of Functional Porous Frameworks (MOFs and COFs) in Electronics
Authors: Souto Manuel , Strutyński Karol , Melle‐Franco Manuel , Rocha João
Published: April 2020

Electroactive organic molecules have received a lot of attention in the field of electronics because of their fascinating electronic properties, easy functionalization and potential low cost towards their implementation in electronic devices. In recent years, electroactive organic molecules have also emerged as promising building blocks for the design and construction of crystalline porous frameworks such as metal–organic frameworks (MOFs) and covalent‐organic frameworks (COFs) for applications in electronics. Such porous materials present certain additional advantages such as, for example, an immense structural and functional versatility, combination of porosity with multiple electronic properties and the possibility of tuning their physical properties by post‐synthetic modifications. In this Review, we summarize the main electroactive organic building blocks used in the past few years for the design and construction of functional porous materials (MOFs and COFs) for electronics with special emphasis on their electronic structure and function relationships. The different building blocks have been classified based on the electronic nature and main function of the resulting porous frameworks. The design and synthesis of novel electroactive organic molecules is encouraged towards the construction of functional porous frameworks exhibiting new functions and applications in electronics.
Fluorescent Arylphosphonic Acids: Synergic Interactions between Bone and the Fluorescent Core
Authors: Zorlu Yunus , Brown Connor , Keil Claudia , Ayhan M. Menaf , Haase Hajo , Thompson Richard B. , Lengyel Imre , Yücesan Gündoğ
Published: April 2020

Herein, we report the third generation of fluorescent probes (arylphosphonic acids) to target calcifications, particularly hydroxyapatite (HAP). In this study, we use highly conjugated porphyrin‐based arylphosphonic acids and their diesters, namely 5,10,15,20‐tetrakis[m‐(diethoxyphosphoryl)phenyl]porphyrin (m‐H8TPPA‐OEt8) and 5,10,15,20‐tetrakis [m‐phenylphosphonic acid]porphyrin (m‐H8TPPA), in comparison with their positional isomers 5,10,15,20‐tetrakis[p‐(diisopropoxyphosphoryl)phenyl]porphyrin (p‐H8TPPA‐iPr8) and 5,10,15,20‐tetrakis [p‐phenylphosphonic acid]porphyrin (p‐H8TPPA), which have phosphonic acid units bonded to sp2 carbon atoms of the fluorescent core. The conjugation of the fluorescent core is thus extended to the (HAP) through sp2‐bonded −PO3H2 units, which generates increased fluorescence upon HAP binding. The resulting fluorescent probes are highly sensitive towards the HAP in rat bone sections. The designed probes are readily taken up by cells. Due to the lower reported toxicity of (p‐H8TPPA), these probes could find applications in monitoring bone resorption or adsorption, or imaging vascular or soft tissue calcifications for breast cancer diagnosis etc.
Graphdiyne Micromotors in Living Biomedia
Authors: Yuan Kaisong , de la Asunción‐Nadal Victor , Li Yuliang , Jurado‐Sánchez Beatriz , Escarpa Alberto
Published: April 2020

Graphdiyne (GDY), a new kind of two‐dimensional (2D) material, was combined with micromotor technology for “on‐the‐fly” operations in complex biomedia. Microtubular structures were prepared by template deposition on membrane templates, resulting in functional structures rich in sp and sp2 carbons with highly conjugated π networks. This resulted in a highly increased surface area for a higher loading of anticancer drugs or enhanced quenching ability over other 2D based micromotors, such as graphene oxide (GO) or smooth tubular micromotors. High biocompatibility with almost 100 % cell viability was observed in cytotoxicity assays with moving micromotors in the presence of HeLa cells. On a first example, GDY micromotors loaded with doxorubicin (DOX) were used for pH responsive release and HeLa cancer cells killing. The use of affinity peptide engineered GDY micromotors was also illustrated for highly sensitive and selective fluorescent OFF–ON detection of cholera toxin B through specific recognition of the subunit B region of the target toxin. The new developments illustrated here offer considerable promise for the use of GDY as part of micromotors in living biosystems.
Scalable Total Syntheses and Structure–Activity Relationships of Haouamines A, B, and Their Derivatives as Stable Formate Salts
Authors: Tsukamoto Hirokazu , Nakamura Saki , Tomida Akito , Doi Takayuki
Published: April 2020

Haouamines A, B, and their derivatives were synthesized via Suzuki–Miyaura coupling and three key cyclization reactions as follows: the newly developed palladium(0)‐catalyzed arylative cyclization of phenylalanine‐derived alkyne–aldehydes with 2‐bromoarylboronic acid (an “anti‐Wacker”‐type cyclization); BF3⋅OEt2‐promoted Friedel–Crafts‐type cyclization of symmetrical electron‐rich aromatic rings adjacent to a tertiary allylic alcohol leading to the indeno‐tetrahydropyridine skeleton; and (cyanomethyl)trimethylphosphonium iodide‐mediated macrocyclization of amino alcohols to afford aza‐paracyclophane precursors. The palladium‐catalyzed reduction of mono‐ and di‐triflate intermediates in the later stages enabled the alteration of both the position and number of hydroxyl groups on the C‐ring. The instability of haouamine B was dramatically improved by salt formation with formic acid. An unambiguous evaluation of the cytotoxicity of the prepared haouamine derivative formates with and without hydroxyl groups at different positions on the C‐ring indicated that the catechol structure in haouamine B produced weak cytotoxicity.
Chimeric antigen receptor‐modified T‐cell therapy for platelet‐derived growth factor receptor α‐positive rhabdomyosarcoma
Authors: Xiao Wei , Wang Jinghua , Wen Xizhi , Xu Bushu , Que Yi , Yu Kuai , Xu Liping , Zhao Jingjing , Pan Qiuzhong , Zhou Penghui , Zhang Xing
Published: April 2020

Background

New immunotherapeutic approaches are urgently needed for metastatic rhabdomyosarcoma, which is associated with poor survival and unsatisfactory treatment outcomes. Platelet‐derived growth factor receptor α (PDGFRA) plays an essential role in the onset and development of rhabdomyosarcoma and is a new potential therapeutic target for rhabdomyosarcoma. The objective of this study was to generate humanized PDGFRA single‐chain variable fragment‐based chimeric antigen receptor (CAR)‐modified T cells (CAR‐T cells) against PDGFRA‐positive rhabdomyosarcoma.

Methods

PDGFRA antigen expression was evaluated in specimens from patients with rhabdomyosarcoma. CAR‐T cells containing a PDGFRA‐specific single‐chain variable fragment was developed in combination with a 4‐1BB costimulatory domain and a CD3‐ζ signaling domain. Specific cytotoxic effects of PDGFRA CAR‐T cells, T‐cell proliferation, and cytokine secretion were investigated in vitro and in vivo.

Results

PDGFRA CAR‐T cells produced large amounts of immune‐promoting cytokines, including interleukin 2, tumor necrosis factor α, and interferon γ, and exhibited efficient cytotoxic activity toward human PDGFRA‐overexpressing rhabdomyosarcoma cells in vitro. In a subcutaneous xenograft model, CAR‐T cells were more effective against PDGFRA‐overexpressing rhabdomyosarcoma than against rhabdomyosarcoma with low PDGFRA expression in terms of tumor regression and patient survival. Expanded CAR‐T cells also were detected in peripheral blood.

Conclusions

The current study demonstrates for the first time that the PDGFRA antigen is a promising target for CAR‐T–cell therapy in rhabdomyosarcoma and likely in a wide spectrum of other PDGFRA‐expressing cancers.
Differences in behavior between surface and cave Astyanax mexicanus may be mediated by changes in catecholamine signaling
Authors: Gallman Kathryn , Fortune Eric , Rivera Daihana , Soares Daphne
Published: April 2020

Astyanax mexicanus is a teleost fish that is in the process of allopatric speciation. Ancestral Astyanax are found in surface rivers and derived blind forms are found in cave systems. Adaptation to life in nutrient poor caves without predation includes the evolution of enhanced food seeking behaviors and loss of defensive responses. These behavioral adaptations may be mediated by changes in catecholaminergic control systems in the brain. We examined the distribution of tyrosine hydroxylase, a conserved precursor for the synthesis of the catecholamines dopamine and noradrenaline, in the brains of surface and cave Astyanax using immunohistochemistry. We found differences in tyrosine hydroxylase staining in regions that are associated with nonvisual sensory perception, motor control, endocrine release, and attention. These differences included significant increases in the diameters of tyrosine hydroxylase immunoreactive soma in cave Astyanax in the olfactory bulb, basal telencephalon, preoptic nuclei, ventral thalamus, posterior tuberculum, and locus coeruleus. These increases in modulation by dopamine and noradrenaline likely indicate changes in behavioral control that underlie adaptations to the cave environment.
Gas‐Phase Synthesis of 3‐Vinylcyclopropene via the Crossed Beam Reaction of the Methylidyne Radical (CH; X2Π) with 1,3‐Butadiene (CH2CHCHCH2; X1Ag)
Authors: He Chao , Zhao Long , Doddipatla Srinivas , Thomas Aaron M. , Nikolayev Anatoliy A. , Galimova Galiya R. , Azyazov Valeriy N. , Mebel Alexander M. , Kaiser Ralf I.
Published: April 2020

The crossed molecular beam reactions of the methylidyne radical (CH; X2Π) with 1,3‐butadiene (CH2CHCHCH2; X1Ag) along with their (partially) deuterated counterparts were performed at collision energies of 20.8 kJ mol−1 under single collision conditions. Combining our laboratory data with ab initio calculations, we reveal that the methylidyne radical may add barrierlessly to the terminal carbon atom and/or carbon−carbon double bond of 1,3‐butadiene, leading to doublet C5H7 intermediates with life times longer than the rotation periods. These collision complexes undergo non‐statistical unimolecular decomposition through hydrogen atom emission yielding the cyclic cis‐ and trans‐3‐vinyl‐cyclopropene products with reaction exoergicities of 119±42 kJ mol−1. Since this reaction is barrierless, exoergic, and all transition states are located below the energy of the separated reactants, these cyclic C5H6 products are predicted to be accessed even in low‐temperature environments, such as in hydrocarbon‐rich atmospheres of planets and cold molecular clouds such as TMC‐1.
Oxidative Catalysis by TAMLs: Obtaining Rate Constants for Non‐Absorbing Targets by UV‐Vis Spectroscopy
Authors: Somasundar Yogesh , Lu Iris C. , Mills Matthew R. , Qian Lisa Y. , Olivares Ximena , Ryabov Alexander D. , Collins Terrence J.
Published: April 2020

Understanding the catalysis of oxidative reactions by TAML activators of peroxides, i. e. iron(III) complexes of tetraamide macrocyclic ligands, advocated a spectrophotometric procedure for quantifying the catalytic activity of TAMLs for colorless targets (kII′, M−1 s−1), which is incomparably more advantageous in terms of time, cost, energy, and ecology than NMR, HPLC, UPLC, GC‐MS and other similar techniques. Dyes Orange II or Safranin O (S) are catalytically bleached by non‐excessive amount of H2O2 in the presence of colorless substrates (S1) according to the rate law: −d[S]/dt=kIkII[H2O2][S][TAML]/(kI[H2O2]+kII[S]+kII′[S1]). The bleaching rate is thus a descending hyperbolic function of S1 : v=ab/(b+[S1]). Values of kII′ found from a and b for phenol and propranolol with commonly used TAML [FeIII{o,o′‐C6H4(NCONMe2CO)2CMe2}2(OH2)]+ are consistent with those for S1 (phenol, propranolol) obtained directly by UPLC. The study sends vital messages to enzymologists and environmentalists.
An Ionic Liquid on a Porous Organic Framework Support: A Recyclable Catalyst for the Knoevenagel Condensation in an Aqueous System
Authors: Chen Peng , Zhang Lei , Sun Jin‐Shi , Xiao En‐Kai , Wu Xian‐Tao , Zhu Guangshan
Published: April 2020

Porous aromatic frameworks (PAFs) that feature a high density of phenyl rings in their robust frameworks are attractive platforms for catalysis because of their extremely high stability, high surface area, and adjustable pore size. In this paper, two PAF‐supported ionic liquids were constructed by introducing ionic liquid units onto the framework of a PAF material PAF‐111 using a series of stepwise post‐synthetic modifications. The basic PAF‐supported ionic liquid with a hydroxy anion exhibited high catalytic activity and high stability, and could undergo at least 10 cycles without any activity loss when catalyzing Knoevenagel condensation reaction under aqueous conditions. It is expected that our study will further promote the development of designing and applying functional PAF materials for catalysis in aqueous systems.
Europium(III) Macrocyclic Chelates Appended with Tyrosine‐based Chromophores and Di‐(2‐picolyl)amine‐based Receptors: Turn‐On Luminescent Chemosensors Selective to Zinc(II) Ions
Authors: Wang Gaoji , Platas‐Iglesias Carlos , Angelovski Goran
Published: April 2020

Invited for this month's cover are the collaborating groups of Dr. Goran Angelovski from the Max Planck Institute for Biological Cybernetics in Tuebingen, Germany and Prof. Carlos Platas‐Iglesias from Centro de Investigacións Científicas Avanzadas (CICA) and Departamento de Química, Facultade de Ciencias, Universidade da Coruña, A Coruña, Spain. The cover image shows chameleon‐like molecules whose luminescence emission can be enhanced selectively and strongly by the coordination of zinc(II) ions. Read the full text of the article at 10.1002/cplu.201900731.
A novel hybrid control technique for bifurcation in an exponential RED algorithm
Authors: Yuan Jun , Zhao Lingzhi , Huang Chengdai , Xiao Min
Published: April 2020

This paper introduces a new hybrid control strategy to control the bifurcation of the delayed congestion model. The delay or gain is taken as the bifurcation parameter to analyze the characteristic root distribution of the linearized system. The stability and existence conditions of Hopf bifurcation are obtained. The results show that by selecting the appropriate method, the dynamics of the controlled system can be changed, and the nonzero equilibrium constant control parameters are maintained. It reveals that when such bifurcation is undesirable or desirable, the hybrid controller can delay or advance the onset of the intrinsic bifurcation. Finally, the case study illustrates and visualizes the effectiveness of the new control strategy in controlling Hopf bifurcation.
A charge‐sharing analog‐to‐digital converter with embedded downconversion using a variable reference voltage
Authors: Pereira Nuno , Goes João
Published: April 2020

In the field of radio receivers, downconversion methods usually rely on one (or more) explicit mixing stage(s) before the analog‐to‐digital converter (ADC). These stages not only contribute to the overall power consumption but also have an impact on area and can compromise the converter's performance in terms of noise and linearity. As an alternative, we propose a receiver architecture that considers the ADC as both a quantizer and a downconverter block. This is achieved through the use of a variable reference signal (in this case, a voltage), as opposed to classic time‐invariant reference signals. When embedded into a charge‐sharing (CS) successive approximation register (SAR) ADC, this varying reference voltage is “saved” in the digital‐to‐analog converter (DAC) capacitor bank during the sampling phase, preventing any conversion errors. Furthermore, a phase‐locked loop (PLL) is used in order to provide an on‐chip solution for the generation of this variable reference voltage, which also removes the need for dedicated bandgap circuits and reference buffers. Post‐layout simulations of an 8‐bit 50 MS/s CS‐SAR ADC show that the proposed “embedded mixing” technique is able to downconvert a high‐frequency signal while also increasing the effective resolution by around 0.5 bits, when compared with a standard DC reference voltage.
The limit of resistance to salinity in the freshwater cyanobacterium Microcystis aeruginosa is modulated by the rate of salinity increase
Authors: Melero‐Jiménez Ignacio José , Martín‐Clemente Elena , García‐Sánchez María Jesús , Bañares‐España Elena , Flores‐Moya Antonio
Published: April 2020

The overall mean levels of different environmental variables are changing rapidly in the present Anthropocene, in some cases creating lethal conditions for organisms. Under this new scenario, it is crucial to know whether the adaptive potential of organisms allows their survival under different rates of environmental change. Here, we used an eco‐evolutionary approach, based on a ratchet protocol, to investigate the effect of environmental change rate on the limit of resistance to salinity of three strains of the toxic cyanobacterium Microcystis aeruginosa. Specifically, we performed two ratchet experiments in order to simulate two scenarios of environmental change. In the first scenario, the salinity increase rate was slow (1.5‐fold increase), while in the second scenario, the rate was faster (threefold increase). Salinity concentrations ranging 7–10 gL‐1 NaCl (depending on the strain) inhibited growth completely. However, when performing the ratchet experiment, an increase in salinity resistance (9.1–13.6 gL‐1 NaCl) was observed in certain populations. The results showed that the limit of resistance to salinity that M. aeruginosa strains were able to reach depended on the strain and on the rate of environmental change. In particular, a higher number of populations were able to grow under their initial lethal salinity levels when the rate of salinity increment was slow. In future scenarios of increased salinity in natural freshwater bodies, this could have toxicological implications due to the production of microcystin by this species.
Novel Rhenium Carbides at 200 GPa
Authors: Khandarkhaeva Saiana , Fedotenko Timofey , Bykov Maxim , Bykova Elena , Chariton Stella , Sedmak Pavel , Glazyrin Konstantin , Prakapenka Vitali , Dubrovinskaia Natalia , Dubrovinsky Leonid
Published: April 2020

Laser heating of rhenium in a diamond anvil cell to 3000±300 K at about 200 GPa results in formation of two previously unknown rhenium carbides, hexagonal WC‐type structured ReC and orthorhombic TiSi2‐type structured ReC2. The shortest C–C distances [1.758(3) Å at 219(5) GPa and 1.850(4) Å at 180(7) GPa] found in honeycomb‐like carbon nets in the structure of ReC2 are quite unusual. The Re–C solid solution formed at multimegabar pressure has the carbon content of ≈ 20 at%.
Triboelectric Harvesting by a Dual‐Tip Peak Power Multiplier under Airtight Condition
Authors: He Shanshan , Zhang Zengxing , Zhai Cong , Xue Xiaobin , Yang Ziyang , Zheng Yongqiu , Cui Danfeng , Xue Chenyang
Published: April 2020

Triboelectric nanogenerators (TENGs) are effective for harvesting mechanical energy and converting into electricity. Such devices have high output voltage and low current, appearing as high output impedance. Impedance mismatches involving these devices create challenges in power usage, storage, and management. Herein, a dual‐tip‐assisted TENG is developed and its electrical output performance under airtight condition is investigated. The generated charges can rapidly accumulate at the dual tip and produce a high potential difference. Such a potential difference accelerates the induced charges’ transfer speed and quantity. Gas discharge occurs once the potential exceeds some threshold, providing a conduction path for accumulated charges. With the help of such dual‐tip peak power multiplier, TENG's peak‐to‐peak short‐circuit current and open‐circuit voltage are 433% and 145% higher, respectively. The peak power reaches a maximum of 34.8 mW with a 100 kΩ load resistance, whereas that of the original TENG is 1.5 mW with a 100 MΩ load resistance, indicating 22.2 times of peak power increase and an optimal matching impedance decrease by three orders of magnitude. The results indicate that this multiplier is meaningful for the optimization of TENG's output and impedance.
Mapping rainstorm erosion associated with an individual storm from InSAR coherence loss validated by field evidence for the Atacama Desert
Authors: Cabré Albert , Remy Dominique , Aguilar Germán , Carretier Sebastien , Riquelme Rodrigo
Published: April 2020

Extreme high‐magnitude and low‐frequency storm events in arid zones provide the necessary runoff to entrain sediments from source areas and therefore dictate the linkages between hillslopes and channels. Nevertheless, the erosive impact of large storms remains difficult to predict. Most of the uncertainty lies in the lack of topographic change maps associated with single hydro‐meteorological events. Consequently, event‐based erosion models are poorly constrained and their extrapolation over long time periods remains uncertain. In this study, a 15‐month Sentinel‐1A coherence time series, optical and field data are used to map the spatial patterns of erosion after the 5‐day storm occurred on March 2015, in the Atacama Desert. The coherence change detection (CCD) analysis suggests that temporal loss of coherence is related to variations in soil moisture, while permanent loss of coherence is related to modification of soil texture by erosion and sedimentation. Importantly, permanent loss of coherence is more apparent on gentle rather than steeper slopes, likely reflecting differences in regolith cover and thickness. These findings can contradict the landscape models predicting higher erosion on steeper hillslopes. The CCD technique represents a promising tool for analysing and modelling sediment connectivity in arid areas, giving a clear picture of the relation between sediment sources and sink pathways. © 2020 John Wiley & Sons, Ltd.
Efficient viscosity contrast calculation for blood flow simulations using the lattice Boltzmann method
Authors: Lehmann Moritz , Müller Sebastian Johannes , Gekle Stephan
Published: April 2020

The lattice Boltzmann method (LBM) combined with the immersed boundary method is a common tool to simulate the movement of red blood cel ls (RBCs) through blood vessels. With very few exceptions, such simulations neglect the difference in viscosities between the hemoglobin solution inside the cells and the blood plasma outside, although it is well known that this viscosity contrast can severely affect cell deformation. While it is easy to change the local viscosity in LBM, the challenge is to distinguish whether a given lattice point is inside or outside the RBC at each time step. Here, we present a fast algorithm to solve this issue by tracking the membrane motion and computing the scalar product between the local surface normal and the distance vector between the closest LBM lattice point and the surface. This approach is much faster than, for example, the ray‐casting method. With the domain tracking applied, we investigate the shape transition of a RBC in a microchannel for different viscosity contrast and validate our method by comparing with boundary‐integral simulations.
Fruit‐based drink sensory, physicochemical, and antioxidant properties in the Amazon region: Murici (Byrsonima crassifolia (L.) Kunth and verbascifolia (L.) DC) and tapereba (Spondia mombin)
Authors: de Souza Vanessa Rosse , Aniceto Adriana , Abreu Joel Pimentel , Montenegro Julia , Boquimpani Bruno , de Jesuz Vanessa Azevedo , Elias Campos Monique de Barros , Marcellini Paulo Sérgio , Freitas‐Silva Otniel , Cadena Rafael , Teodoro Anderson Junger
Published: April 2020

Increased fruit consumption due its protective effect on the organism is accompanied by the development of the processing industry of these products. The aim of this work was to optimize fruit pulp‐based beverage formulations from the murici and tapereba Amazon region, taking into account their sensory acceptance and antioxidant activity. Total soluble solid content, reducing sugar content, titratable acidity contents, pH, and ascorbic acid content were determined in pulps and formulations. The total content phenolic compounds and antioxidant activity were also evaluated. A 22 factorial experiment was formulated to optimize ingredients for the production of murici and tapereba fruit drinks. The murici pulp had higher acidity and higher ascorbic acid content. The analysis of phenolic compounds and antioxidant activity presented higher quantity in tapereba pulp. Tapereba‐based beverages had better acceptance by the evaluated criteria. Fruit‐based beverages murici and tapereba are a well‐accepted product and have important nutritional characteristics.
Validation of the Brief Assessment of Impaired Cognition and the Brief Assessment of Impaired Cognition Questionnaire for identification of mild cognitive impairment in a memory clinic setting
Authors: Jørgensen Kasper , Nielsen Thomas R. , Nielsen Ann , Waldorff Frans B. , Waldemar Gunhild
Published: April 2020

Objectives

The aim of this study was to validate the Brief Assessment of Impaired Cognition (BASIC) and the Brief Assessment of Impaired Cognition Questionnaire (BASIC‐Q) for identification of mild cognitive impairment (MCI) in a memory clinic setting.

Methods

A total of 163 sociodemographically matched patients (MCI, n = 42, and dementia, n = 121) and 83 control participants were included in the study. Two instruments were validated: (a) BASIC, including the components self‐report, informant report, and two brief cognitive tests, and (b) BASIC‐Q, including the components self‐report, informant report, and orientation. BASIC can be administered in 5 minutes and BASIC‐Q in less than 5 minutes.

Results

A high discriminative validity for MCI vs control participants was found for both BASIC (sensitivity 0.86, specificity 0.89) and BASIC‐Q (sensitivity 0.88, specificity 0.88). In comparison, the MMSE had low sensitivity (0.61) and moderate specificity (0.72). All components of BASIC and BASIC‐Q contributed significantly to differentiate MCI from control participants. The components of BASIC and BASIC‐Q also contributed significantly to differentiate MCI from dementia, except for self‐report, which was identical in the two groups.

Conclusions

Both BASIC and BASIC‐Q are brief, valid, and effective instruments for identification of patients with possible MCI in a memory clinic setting. Further cross‐validation of the instruments in a general practice or primary care setting is needed.
Discriminating stress from rest based on resting‐state connectivity of the human brain: A supervised machine learning study
Authors: Zhang Wei , Llera Alberto , Hashemi Mahur M. , Kaldewaij Reinoud , Koch Saskia B. J. , Beckmann Christian F. , Klumpers Floris , Roelofs Karin
Published: April 2020

Acute stress induces large‐scale neural reorganization with relevance to stress‐related psychopathology. Here, we applied a novel supervised machine learning method, combining the strengths of a priori theoretical insights with a data‐driven approach, to identify which connectivity changes are most prominently associated with a state of acute stress and individual differences therein. Resting‐state functional magnetic resonance imaging scans were taken from 334 healthy participants (79 females) before and after a formal stress induction. For each individual scan, mean time‐series were extracted from 46 functional parcels of three major brain networks previously shown to be potentially sensitive to stress effects (default mode network (DMN), salience network (SN), and executive control networks). A data‐driven approach was then used to obtain discriminative spatial linear filters that classified the pre‐ and post‐stress scans. To assess potential relevance for understanding individual differences, probability of classification using the most discriminative filters was linked to individual cortisol stress responses. Our model correctly classified pre‐ versus post‐stress states with highly significant accuracy (above 75%; leave‐one‐out validation relative to chance performance). Discrimination between pre‐ and post‐stress states was mainly based on connectivity changes in regions from the SN and DMN, including the dorsal anterior cingulate cortex, amygdala, posterior cingulate cortex, and precuneus. Interestingly, the probability of classification using these connectivity changes were associated with individual cortisol increases. Our results confirm the involvement of DMN and SN using a data‐driven approach, and specifically single out key regions that might receive additional attention in future studies for their relevance also for individual differences.
Comparison of the effects of litter covering and incorporation on infiltration and soil erosion under simulated rainfall
Authors: Wang Lunjiang , Zhang Guanghui , Zhu Pingzong , Wang Xue
Published: April 2020

Plant litter can either cover on soil surface or be incorporated into top‐soil layer in natural ecosystems. Their effects on infiltration and soil erosion are likely quite different. This study was performed to compare the effects of litter covering on soil surface and being incorporated into top‐soil layer on infiltration and soil erosion under simulated rainfall. Four litter types (needle‐leaf, broad‐leaf, brush, and herb) were collected from fields and applied to cover on soil surface or to be incorporated into top‐soil layer (5 cm) at the same rate (0.2 kg/m2). The simulated rainfalls (40 and 80 mm/hr) were run at two slope angles (10° and 20°). The results showed that the mean infiltration rate of litter covering treatment was 1.4 times as great as that of litter incorporated. Litter covering enhanced infiltration via protecting surface from soil sealing. Whereas, litter incorporation affected infiltration by its water repellency. Soil erosion of litter incorporated treatment was 5.4 times as large as that of litter covered treatment, which was attributed to the changes in surface litter coverage and soil erosion resistance. Litter type affected soil erosion through the variations in litter coverage and litter morphology. For litter covering treatment, litter coverage can explain the major variance of soil loss on the slopes. Whereas, for litter incorporated treatment, both the influences of litter coverage and litter length on soil erosion resistance were considered necessary to well explain the variance of soil loss. The results also showed that the benefits of litter to control soil erosion declined with rainfall intensity and slope gradient for both covering and incorporated treatments. The results of this study are helpful to understand the mechanisms of litter influencing hydrological and erosion processes on hillslopes.
Non‐linear quickflow response as indicators of runoff generation mechanisms
Authors: Scaife Charles I. , Singh Nitin K. , Emanuel Ryan E. , Miniat Chelcy Ford , Band Lawrence E.
Published: April 2020

Linking quickflow response to subsurface state can improve our understanding of runoff processes that drive emergent catchment behaviour. We investigated the formation of non‐linear quickflows in three forested headwater catchments and also explored unsaturated and saturated storage dynamics, and likely runoff generation mechanisms that contributed to threshold formation. Our analyses focused on two reference watersheds at the Coweeta Hydrologic Laboratory (CHL) in western North Carolina, USA, and one reference watershed at the Susquehanna Shale Hills Critical Zone Observatory (SHW) in Central Pennsylvania, USA, with available hourly soil moisture, groundwater, streamflow, and precipitation time series over several years. Our study objectives were to characterise (a) non‐linear runoff response as a function of storm characteristics and antecedent conditions, (b) the critical levels of shallow unsaturated and saturated storage that lead to hourly flow response, and (c) runoff mechanisms contributing to rapidly increasing quickflow using measurements of soil moisture and groundwater. We found that maximum hourly rainfall did not significantly contribute to quickflow production in our sites, in contrast to prior studies, due to highly conductive forest soils. Soil moisture and groundwater dynamics measured in hydrologically representative areas of the hillslope showed that variable subsurface states could contribute to non‐linear runoff behaviour. Quickflow generation in watersheds at CHL were dominated by both saturated and unsaturated pathways, but the relative contributions of each pathway varied between catchments. In contrast, quickflow was almost entirely related to groundwater fluctuations at SHW. We showed that co‐located measurements of soil moisture and groundwater supplement threshold analyses providing stronger prediction and understanding of quickflow generation and indicate dominant runoff processes.
Knowledge Representation with Ontologies and Semantic Web Technologies to Promote Augmented and Artificial Intelligence in Systems Engineering
Authors: Hagedorn Thomas , Bone Mary , Kruse Benjamin , Grosse Ian , Blackburn Mark
Published: April 2020

This article discusses knowledge representation using ontologies and semantic web technologies to enable artificial intelligence (AI) for Systems Engineering. Technology trends indicate new methods and tools for digital engineering will incorporate AI and machine learning (ML) technologies. ML techniques support classification, clustering, and association identification, but struggle to explain the rationale for decision making, where multi‐domain semantic modeling and rule‐based reasoning can excel. Knowledge representation plays a key role in applying this type of AI. Ontologies are a means to domain modeling and reasoning required across Digital Thread domains instantiated in digital system models (DSM). These evolve over time as digital twins, which co‐evolve with physical instantiations of a DSM. Semantic technologies and ontologies formalize knowledge as an enabler for reasoning, with interoperable ontologies enabling reason about systems engineering across domains.
Motivating a Systems Theory of AI
Authors: Cody Tyler , Adams Stephen , Beling Peter
Published: April 2020

Artificial intelligence is an emerging technology with few principled engineering frameworks guiding its application, particularly theoretical frameworks for understanding the interrelationships between systems and their learning processes. We propose addressing this gap by using systems theory as a mathematical superstructure for learning theory. Such a framework would connect learning theory and machine learning directly to model‐based systems engineering practices. A general systems learning theory would show how general learning processes relate to general systems and, when applied to particular systems, could reveal how particular learning processes relate to particular systems. Condition‐based maintenance and actuators for context to discuss these concepts.
AI as Systems Engineering Augmented Intelligence for Systems Engineers
Authors: Rouse William B.
Published: April 2020

AI technology's rapid development has led to various arguments for SE for AI, as well as AI for systems engineering. This article argues for and illustrates a third perspective — AI as systems engineering. A conceptual architecture articulates employing AI as an assistant systems engineering engineer. This cognitive assistant understands systems engineering concepts, principles, methods, and tools as well as the workflows and preferences of the particular supported engineer. The vision is a cognitive assistant understanding your domain, your current intentions, and you.
Connecting experiences of community shared responsibility and collective competence to the well‐being of adults in military families
Authors: O'Neal Catherine W. , Mancini Jay A. , Bowen Gary L.
Published: April 2020

Drawing from the social organization theory of action and change, the role of community‐capacity elements (shared responsibility and collective competence) for military members' and their civilian spouses' well‐being is examined. With data from 266 active‐duty military families, military members and their spouses are classified by theory‐based community‐capacity type. A path analysis examines associations between community types, elements of military context (rank and transitions), and dimensions of well‐being (anxiety, depressive symptoms, self‐efficacy, life satisfaction). There were few variations in community capacity across rank and transitions. For military members' and their civilian spouses, community types were differentially associated with well‐being, particularly in disengaged and synergetic communities. Well‐being was generally highest for those in synergistic communities (high shared responsibility and collective competence) and lowest in disengaged communities (low shared responsibility and collective competence). Findings inform intervention and prevention efforts seeking to activate communities as a mechanism for fostering well‐being.
Assessment of risk factors, and racial and ethnic differences in hepatocellular carcinoma
Authors: Thylur Ramesh P , Roy Sanjit K , Shrivastava Anju , LaVeist Thomas A , Shankar Sharmila , Srivastava Rakesh K
Published: April 2020

Despite improved screening and surveillance guidelines, significant race/ethnicity‐specific disparities in hepatocellular carcinoma (HCC) continue to exist and disproportionately affect minority and disadvantaged populations. This trend indicates that social determinants, genetic, and environmental factors are driving the epidemic at the population level. Race and geography had independent associations with risk of mortality among patients with HCC. The present review discusses the risk factors and issues related to disparities in HCC. The underlying etiologies for these disparities are complex and multifactorial. Some of the risk factors for developing HCC include hepatitis B (HBV) and hepatitis C (HCV) viral infection, nonalcoholic fatty liver disease, nonalcoholic steatohepatitis, smoking and alcohol consumption. In addition, population genetics; socioeconomic and health care access; treatment and prevention differences; and genetic, behavioral, and biological influences can contribute to HCC. Acculturation of ethnic minorities, insurance status, and access to health care may further contribute to the observed disparities in HCC. By increasing awareness, better modalities for screening and surveillance, improving access to health care, and adapting targeted preventive and therapeutic interventions, disparities in HCC outcomes can be reduced or eliminated.