bluuebunny/crossref_metadata_2025 huggingface dataset:
Virus Replication in Multicellular Photosynthetic Life Forms
Authors: McKeown Dean , Schroeder Declan C
Published: September 2019

Photosynthesis originated from endosymbiosis of cyanobacterial‐like organisms, which ultimately became chloroplasts. It is an ancient process that has evolved to produce a variety of types of photosynthetic eukaryotic organisms that we find today, that is, terrestrial plants and aquatic algae. Similarly, viruses are considered ancient with growing evidence for the theory that viruses arose before the last universal cellular ancestor. Despite both photosynthetic and virus life forms having evolved side by side since time immemorial, plants and eukaryotic algae have very different viruses that infect them. Very little similarities are shared in both the types and nature of the infection. In fact, viruses of photosynthetic eukaryotic multicellular organisms exemplify how different algae are from plants.

Key Concepts

Photosynthetic organisms appeared 3.2–3.5 billion years ago.

The most abundant and diverse viruses have dsDNA genomes.

NCLDVs are estimated to have evolved 2–2.7 billion years ago, close to the origin of eukaryotes.

The known host range of NCLDVs includes multiple eukaryotic kingdoms, which is the broadest of any dsDNA virus group, which usually infect a single kingdom.

The familyPhycodnaviridae(‘phyco’=algae, ‘dna’=DNA, ‘viridae’=virus family) are NCLDVs that infect algae.

Most plant viruses (66.7%) have ssRNA genomes.

Plant viruses use long‐distance transport as a key mechanism for transmission. This would be possible in some macroalgae which have vascular tissue (sieve tubes), such as kelps, but these sieve tubes are less extensive than the xylem and phloem of plants.

The NCLDVs are a major algal virus group which may be absent in plants, which are instead predominately infected by ssRNA viruses.

Eukaryotic multicellular macroalgae or seaweed are predominantly infected by dsDNA viruses.
Signalling Underlying Wound Healing
Authors: Cook Sophie R , Hart William S , Zatorski Jonathan M , Flick Matthew J , Deppmann Christopher D
Published: September 2019

Wound healing is critical for normal tissue function and the survival of most multicellular organisms. Understanding the biochemical and cellular mechanisms underlying constructive physiological wound healing is crucial for developing therapies to aid in repair and regeneration. Wound healing involves multiple systems including blood, vasculature, somatosensory, immune system and the skin. Following vascular damage, coagulation system activation occurs resulting in clot formation and cell signalling events in both cells of the vasculature (e.g. endothelial cells) as well as circulating cells (e.g. platelets, leukocytes) in order to drive cessation of blood loss. Pain signalling is initiated in part by surrounding inflammatory cues and is used to prevent further damage to the wound. Following these initial responses to the wound, healing/regeneration returns the damaged tissue to a functional state. This occurs by engaging the fibrin network to create a new microenvironment architecture. A broad overview is presented of how the different organ systems are integrated to repair tissue after a wound.

Key Concepts

Blood coagulation is driven by exposure of the subendothelial receptor tissue factor that drives activation of downstream clotting factors, including activation of the central protease thrombin. Platelet activation is mediated by thrombin cleavage of cell surface protease‐activated receptors, tight receptor‐mediated binding to collagen or activation of the purinergic receptors (i.e. P2Y1, P2Y12). In addition to platelet activation, thrombin catalyses the conversion of fibrinogen into fibrin, the primary structural component of the blood clot.

Immune cells like mast cells and macrophages are recruited and activated once a wound occurs, releasing cytokines and histamine. This inflammatory response aids in promoting pain signalling and eventually aids in the wound healing process.

In response to the wound and release of inflammatory factors (e.g. cytokines, histamine, bradykinin, NGF and PGE2) sensory neurons become hypersensitive. This hypersensitisation (hyperalgesia) leads to innocuous tactile information to be interpreted as painful by both the peripheral nervous system (PNS) and central nervous system (CNS).

Numerous stem cell populations derived from the dermis and hair follicle contribute to wound remodelling. These stem cells differentiate into cell types like myofibroblasts, which either repopulate the site of the wound and/or deposit new extracellular matrix proteins to form a fibrotic scar.

A balance between Wnt and TGF‐β signalling guides regenerative and healing processes, respectively. Wnt signalling leads to cell proliferation and the reappearance of hair follicles inducing wounds to heal without a scar. TGF‐β signalling induces reticular dermis stem cells to differentiate into myofibroblasts, which leads to scar tissue.
Rescue levodopa‐carbidopa intestinal gel (LCIG) therapy in Parkinson’s disease patients with suboptimal response to deep brain stimulation
Authors: Elkouzi Ahmad , Ramirez‐Zamora Adolfo , Zeilman Pam , Barabas Matthew , Eisinger Robert S. , Malaty Irene A. , Okun Michael S. , Almeida Leonardo
Published: September 2019

Objective

To evaluate the effectiveness of levodopa‐carbidopa intestinal gel (LCIG) as an add‐on rescue therapy following deep brain stimulation (DBS) for treatment of motor fluctuations.

Background

Both DBS and LCIG are FDA‐approved therapies for treatment of motor fluctuations in advanced PD. Few studies have examined dual therapy for refractory motor fluctuations and it is unknown what the effect on quality of life will be in advanced PD.

Methods

We conducted a retrospective study using a large database of all medical and surgical PD cases at the University of Florida. Six patients were identified with DBS who subsequently received rescue LCIG therapy. The clinical histories, indications for intervention and outcomes were reviewed.

Results

All patients were managed initially with DBS (bilateral STN DBS (n = 3), bilateral GPi DBS (n = 1), unilateral GPI DBS (n = 2)). Patients with well‐placed (n = 3) and suboptimally placed DBS leads (n = 3) had significant reduction in their motor fluctuations with improvement in the off‐medication time after rescue LCIG therapy. Improvement in quality of life scores (PDQ‐39) was appreciated in four DBS patients following the addition of LCIG therapy.

Conclusions

LCIG is a promising add‐on rescue therapy for select patients with existing DBS devices. The LCIG may possibly reduce motor fluctuations and improve quality of life in advanced PD irrespective of the DBS target or the accuracy of lead placement. Dual therapy may also be ideal for patients who are considered high risk for additional DBS surgeries.
How does naloxone distribution relate to opioid overdose deaths?
Authors: Knopf Alison
Published: September 2019

The $64,000 question — or however much money has been spent on naloxone, the lifesaving medication that rescues opioid overdose victims — is whether the distribution of the medication has an effect on overdose deaths.
FDA: Avoid THC‐containing vaping products
Authors: Knopf Alison
Published: September 2019

Last week, as respiratory illnesses linked to vaping spread, some resulting in deaths, the Food and Drug Administration on Sept. 6 issued an alert focusing on tetrahydrocannabinol (THC)‐containing products (see story, page 1).
Stiffness, Energy Dissipation, and Hyperelasticity in Hierarchical Multilayer Composite Nanocoated Open‐Cell Polyurethane Foams
Authors: Cura' Francesca , Sesana Raffaella , Zhang Xiao-Chong , Scarpa Fabrizio , Lu Wen Jiang , Peng Hua-Xin
Published: September 2019

The manufacturing, testing, and modeling of a class of open‐cell polyurethane (PU) foams doped with multiwalled carbon nanotubes (MWCNTs) and nano‐PU dispersions (PUDs) and subjected to quasistatic cycling compressive loading at large deformations are described. The doped nanoink foams are produced using a multiple‐step dip coating technique that makes the development of nano‐based porous materials by postprocessing existing off‐the‐shelf open‐cell foams possible. Tests are conducted up to 18.5% of compressive strain to identify loading/unloading moduli and energy absorbed after five cycles of stabilization. Hyperelastic Ogden models also considering the Mullins effect for cyclic loading are used to identify the constitutive parameters for these foams. The results show that the use of MWCNT layers provides an effective increase in the stiffness and energy absorbed compared with pristine and nano‐PUDs‐treated foams. The volume average energy absorbed after the stabilization cycles is increased by 200% compared with the pristine foam when the MWCNT layers are used. The parameters of the constitutive models extracted from the tests show that these nanoink foams are modeled following state‐of‐the‐art hyperelastic representations.
Visible‐Light‐Induced Alkoxylation of Quinoxalin‐2(1H)‐ones with Alcohols for the Synthesis of Heteroaryl Ethers
Authors: Zhao Lulu , Wang Lei , Gao Yanhui , Wang Zhiming , Li Pinhua
Published: September 2019

A direct and simple strategy to heteroaryl ethers via a visible‐light‐induced alkoxylation of quinoxalin‐2(1H)‐ones with alcohols under ambient conditions was developed. The commercially available, low cost alcohols served as alkoxylation reagents and solvents. This reaction has advantages of novel protocol, mild conditions, good functional‐group tolerance, and high yields of products.

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Hydrodynamics and mass transfer of gas–liquid flow in micropacked bed reactors with metal foam packing
Authors: Sang Le , Tu Jiacheng , Cheng Han , Luo Guangsheng , Zhang Jisong
Published: September 2019

Hydrodynamics and mass transfer of gas–liquid flow such as pressure drop, liquid holdup, and gas–liquid mass‐transfer coefficient in micropacked bed reactors (μPBRs) with metal foam packing are investigated with an automated platform. Parametric studies are conducted varying gas and liquid superficial velocities, pore diameters of foam packing, and liquid physical properties. Experimental results show that μPBRs with foam packing have comparative mass transfer rate and 10 times lower pressure drop compared to the microparticles. The values of mass‐transfer coefficient for three types of foam packing in μPBRs are 1–2 orders of magnitude larger than those in large‐scale trickle bed reactors with foam packing. Furthermore, empirical correlations of pressure drop, liquid holdup, and gas–liquid mass‐transfer coefficient in μPBRs with foam packing are proposed and the predicted values are found to be in good agreement with the experimental values.
Unique Bora[1]ferrocenophanes with Sterically Protected Boron: A Potential Gateway to Helical Polyferrocenes
Authors: Bhattacharjee Hridaynath , Zhu Jianfeng , Müller Jens
Published: September 2019

Silicon‐bridged [1]ferrocenophanes are a versatile class of monomers to obtain well‐defined metallopolymers, however, their boron‐bridged analogues are far less utilized despite being significantly higher strained. We assumed that the reactivity of known bora[1]ferrocenophanes towards ring‐opening polymerization is hampered by π‐donating R2N groups at the bridging boron atom and therefore prepared the first bora[1]ferrocenophanes lacking such electronic stabilization. The new, isolated ferrocenophane with a 2,4,6‐triisopropylphenyl group attached to the bridging boron atom exhibits the most tilted Cp rings among all isolated strained sandwich compounds [α(DFT)=33.3°] with a measured record value of the bathochromic shift (λmax=516 nm). Attempts to purify the mesityl analogue by vacuum sublimation transformed this monomer to a purple‐colored polymer that resulted in Cotton effects in circular dichroism spectroscopy. DFT calculations revealed a left‐handed helical structure for this polymer. This is the first evidence for a polyferrocene with a chiral secondary structure.
Insights into the interactions between collagen and a naturally derived crosslinker, oxidized chitosan oligosaccharide
Authors: Chen Yining , Dan Nianhua , Huang Yanping , Yang Changkai , Dan Weihua , Liang Yongxian
Published: September 2019

Collagen has been widely applied to biomaterials. However, it must be chemically fixed before it can be used. The aim of this work is to study on the crosslinking effect of a naturally derived oxidized chitosan oligosaccharide (OCOS) on collagen type I. The physicochemical properties and biocompatibility of the crosslinked collagen (OCOS‐Col) were evaluated. The FTIR spectroscopy showed that crosslinking via OCOS had no impact on the structural integrity of collagen. DSC and TG tests showed that the thermal stability of crosslinked collagen was improved significantly, while the crosslinking density test indicated that the amino groups of collagen could predominantly react with the available aldehyde groups of OCOS. The mechanical properties, hydrophilicity, and enzymatic degradation test showed that the crosslinked material had improved properties. However, the porosity test showed that the crosslinked material was more compact, which was consistent with the AFM observation that crosslinked collagen revealed a denser network structure. Cytotoxicity test showed that the crosslinked collagen was conducive to cell adhesion, growth, and proliferation. In conclusion, this work reveals that OCOS stabilized collagen as a crosslinker, preserved its triple helical structure, and reserved its good biocompatibility. OCOS was proven to be a safe and reliable crosslinker for collagen. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48489.
Social structure and spatial distribution of bottlenose dolphins (Tursiops truncatus) along the Croatian Adriatic coast
Authors: Pleslić Grgur , Rako‐Gospić Nikolina , Miočić‐Stošić Jure , Blazinić Vučur Tihana , Radulović Marko , Mackelworth Peter , Frleta‐Valić Maša , Holcer Draško
Published: September 2019

Previous studies suggest that the common bottlenose dolphin population in the Croatian Adriatic Sea is structured into distinct local communities. However, their home ranges and levels of interaction remain unknown.

Dedicated boat‐based surveys were conducted seasonally, in three adjacent study sites from 2013 to 2017. Photo‐identification data were used to identify distinct local communities by relating the social structure descriptors to the home ranges of individual animals, and to determine the community home ranges and identify the levels of interactions between them.

The overlaps between the home ranges of individuals (50 and 95% kernel density estimators [KDE]) were positively correlated to association strengths between them. Three distinct communities were identified by the hierarchical cluster analysis. The individuals' 95% KDE home range overlaps and association strengths were significantly higher within the three communities than between them, indicating both social and spatial segregation.

The 95% KDE home ranges of the communities showed very low to no overlap. The individuals ranged mainly centrally within the home range of their respective community. The probabilities of movement, expressed as lagged identification rates, were significantly higher within than between community home ranges. However, 37 out of 1024 identified individuals were observed in more than one community home range, indicating that the communities are not isolated.

Four out of the six Sites of Community Importance currently in place within the Croatian Adriatic Sea lie within the home ranges of the three local bottlenose dolphin communities. Once these sites are declared as Special Areas of Conservation, the management scheme will need to accommodate for differences in the spatial and social ecology of these communities, and environmental and anthropogenic factors acting upon them. The results of this work provide baseline information for such tailored management.
Guaranteeing performance for uncertain nonlinear systems with bounded state constraint and mismatching condition
Authors: Xu Jinquan , Fang Hao , Chen Ye‐Hwa , Guo Hong , Ding Xiaofeng
Published: September 2019

The control design problem for the uncertain nonlinear system with bounded state constraint and mismatching condition is considered in this paper. The uncertainty in the system, which may be due to unknown system parameters and external disturbance, is nonlinear and time‐varying. The state of the system is constrained to be bounded. The system does not satisfy the (global) matching condition. A creative one‐to‐one state transformation is proposed by converting the bounded states into the unbounded ones. A step‐by‐step state transformation is proposed to convert the mismatched system into a matched system. The robust control is then proposed based on the transformed system. The control is demonstrated to be able to guarantee the uniform boundedness and uniform ultimate boundedness of the system in the presence of uncertainty, while the state constraint can be always guaranteed.
Study on vehicle active suspension system control method based on homogeneous domination approach
Authors: Meng Qinghua , Chen Chih‐Chiang , Wang Pan , Sun Zong‐Yao , Li Bingji
Published: September 2019

In an active suspension system, there is an actuator mounted between the sprung mass and the unsprung mass to change the stiffness and damp of the suspension for ride comfort and handling stability. Because the active suspension control system is an under‐actuated system, the control problem of the active suspension is challenging but interesting. In order to solve this issue, a novel vehicle active suspension control method based on homogeneous domination approach is proposed in this paper. Firstly, a groundhook control model is constructed according to the general active suspension dynamic model. In order to deal with the additional terms of the control system which are harmful for convergence, a homogeneous domination approach is used to construct an active suspension homogeneous controller (ASHC). A useful technical theorem is proposed in the stability analysis to show that the proposed ASHC can guarantee the states of the active suspension system being stabilized. Compared with the SMC method and without any controller (passive suspension), the simulation results indicate that the proposed ASHC is effective.
Examining children's ability to delay reward: Is the delay discounting task a suitable measure?
Authors: Burns Patrick , Fay Olivia , McCafferty Mary‐Frances , McKeever Veronica , Atance Cristina , McCormack Teresa
Published: September 2019

Discounting the value of delayed rewards has primarily been measured in children with the delay of gratification task and in adolescents and adults with the delay discounting task. In the present study, we assessed the suitability of the delay discounting task as a measure of temporal discounting in children. A sample of 7‐ to 9‐year‐olds (N = 98) completed a delay discounting task, a delay of gratification task, a sensation seeking measure, and IQ measures. In addition, teacher‐based assessments of attention‐deficit/hyperactivity disorder traits were measured. The results indicated that the majority of children produced meaningful data on the discounting task and discounted rewards hyperbolically. Children with an elevated risk of attention‐deficit/hyperactivity disorder showed a trend towards discounting future rewards on the delay discounting task more steeply than did those at low risk. However, delay discounting was unrelated to either delay of gratification or sensation seeking. We interpret these results as providing some support for the use of delay discounting as a measure of intertemporal choice in children, although the results also suggest that delay discounting and delay of gratification tasks may tap different processes in this population.
Deletion of neural tube defect‐associated geneMthfd1lcauses reduced cranial mesenchyme density
Authors: Shin Minhye , Vaughn Amanda , Momb Jessica , Appling Dean R.
Published: September 2019

Background

Periconceptional intake of supplemental folic acid can reduce the incidence of neural tube defects by as much as 70%, but the mechanisms by which folic acid supports cellular processes during neural tube closure are unknown. The mitochondrial 10‐formyl‐tetrahydrofolate synthetase MTHFD1L catalyzes production of formate, thus generating one‐carbon units for cytoplasmic processes. Deletion ofMthfd1lcauses embryonic lethality, developmental delay, and neural tube defects in mice.

Methods

To investigate the role of mitochondrial one‐carbon metabolism during cranial neural tube closure, we have analyzed cellular morphology and function in neural tissues inMthfd1lknockout embryos.

Results

The head mesenchyme showed significantly lower cellular density inMthfd1lnullizygous embryos compared to wildtype embryos during the process of neural tube closure. Apoptosis and neural crest cell specification were not affected by deletion ofMthfd1l. Sections from the cranial region ofMthfd1lknockout embryos exhibited decreased cellular proliferation, but only after completion of neural tube closure. Supplementation of pregnant dams with formate improved mesenchymal density and corrected cell proliferation in the nullizygous embryos.

Conclusions

Deletion ofMthfd1lcauses decreased density in the cranial mesenchyme and this defect is improved with formate supplementation. This study reveals a mechanistic link between folate‐dependent mitochondrially produced formate, head mesenchyme formation and neural tube defects.
Isolation and Antimacrofouling Activity of Indole and Furoquinoline Alkaloids from ‘Guatambú’ Trees (Aspidosperma australe and Balfourodendron riedelianum)
Authors: Pérez Miriam , Pis Diez Cristian M. , Belén Valdez María , García Mónica , Paola Analía , Avigliano Esteban , Palermo Jorge A. , Blustein Guillermo
Published: September 2019

In this work, the antifouling activity of five alkaloids, isolated from trees of the Atlantic rainforest, was studied. The tested alkaloids were olivacine (1), uleine (2) and N‐methyltetrahydroellipticine (3) from Aspidosperma australe (‘yellow guatambú’) and the furoquinoline alkaloids kokusaginine (4) and flindersiamine (5) from Balfourodendron riedelianum (‘white guatambú’). All these compounds can be isolated from their natural sources in high yields in a sustainable way. The five compounds were subjected to laboratory tests (attachment test of the mussel Mytilus edulis platensis) and field trials, by incorporation into soluble matrix paints, and 45 days of exposure of the painted panels in the sea. The results show that compound 3 is a very potent antifoulant, and that compounds 4 and 5 are also very active, while compounds 1 and 2 did not show any significant antifouling activity. These results open the way for the development of environmentally friendly antifouling agents, based on abundant and easy‐to‐purify compounds that can be obtained in a sustainable way.
MicroRNA‐506 upregulation contributes to sirtuin 1 inhibition of osteoclastogenesis in bone marrow stromal cells induced by TNF‐α treatment
Authors: Yan Shu , Miao Lujie , Lu Yahua , Wang Liangzhi
Published: September 2019

As a deacetylase relying on NAD, sirtuin 1 (SIRT1) has been proven to inhibit osteoclastogenesis directly by repressing reactive oxygen species (ROS) production and TRPV1 channel stimulation modulated by TNF‐α. MicroRNAs do not have coding functions, but they influence the expression of particular genes after transcription. Nevertheless, the current understanding of the impact of SIRT1 on osteoclastogenesis is insufficient. Our research explored whether and how miRNAs contributed to osteoclast differentiation modulated by SIRT1 in vitro. In osteoclastogenesis induced by RANKL in bone marrow‐derived macrophages (BMMs), repression of SIRT1 expression and enhancement of miR‐506 expression were discovered. Transfection with an miR‐506 inhibitor repressed miR‐506 concentration in BMMs treated with RANKL. Additional research revealed that BMMs with repressed miR‐506 treated with RANKL displayed phenotypes with suppressed osteoclastogenesis, as demonstrated by TRAP staining, reduced function, decreased expression of osteoclast markers and correlated genes, and reduced multinuclear cell quantity. Bioinformatics prediction outcomes and the dual‐luciferase reporter test suggested that miR‐506 targeted the SIRT1 3′‐UTR for silencing. Decreased miR‐506 in BMMs induced by RANKL caused SIRT1 upregulation. Additionally, treatment with EX‐527 (SIRT1 repressor) or SIRT1 silencing attenuated repression caused by miR‐506 depletion in BMMs treated with RANKL. Furthermore, TNF‐α was repressed via miR‐506 inhibition but was enhanced following EX‐527 incubation as well as SIRT1 depletion. TRPV1 channel stimulation and ROS generation, which was related to osteoclastogenesis, were reduced via miR‐506 depletion. miR‐506 modulated osteoclastogenesis by targeting SIRT1 expression in part through modulation of the TRPV1 channel, ROS production, and TNF‐α.
Implications of the Molybdenum Coordination Environment in MFI Zeolites on Methane Dehydroaromatisation Performance
Authors: Agote‐Arán Miren , Fletcher Rachel E. , Briceno Martha , Kroner Anna B. , Sazanovich Igor V. , Slater Ben , Rivas María E. , Smith Andrew W. J. , Collier Paul , Lezcano‐González Inés , Beale Andrew M.
Published: September 2019

The structure and activity of Mo/Silicalite‐1 (MFI, Si/Al=∞) were compared to Mo/H‐ZSM‐5 (MFI, Si/Al=15), a widely studied catalyst for methane dehydroaromatisation (MDA). The anchoring mode of Mo was evaluated by in situ X‐ray absorption spectroscopy (XAS) and density functional theory (DFT). The results showed that in Mo/Silicalite‐1, calcination leads to dispersion of MoO3 precursor into tetrahedral Mo‐oxo species in close proximity to the microporous framework. A weaker interaction of the Mo‐oxo species with the Silicalite‐1 was determined by XAS and DFT. While both catalysts are active for MDA, Mo/Silicalite‐1 undergoes rapid deactivation which was attributed to a faster sintering of Mo species leading to the accumulation of carbon deposits on the zeolite outer surface. The results shed light onto the nature of the Mo structure(s) while evidencing the importance of framework Al in stabilising active Mo species under MDA conditions.
Modeling and Simulation of the 1,3‐Butadiene Extraction Process at Turndown Capacity
Authors: Tripathi Namit , Xu Qiang , Palanki Srinivas
Published: September 2019

As cracker feed around the globe is trending towards lighter feedstocks, butadiene production facilities worldwide are now run at turndown capacities. Models are developed to study how operation at turndown ratios of feed rates affects the purity of 1,3‐butadiene. The optimal solvent‐to‐feed ratio was found to be in the range of 6–7 when the plant is run at normal throughput; however, it is necessary to change the solvent‐to‐feed ratio in the range of 10–11 when the plant is operating at turndown capacity. Dynamic simulations indicate that the effect of fluctuations in the feed flow rate on product purity can be minimized by a ratio controller to change the solvent flow rate and a composition controller to alter the side‐draw flow rate.
A Scaffold‐Diversity Synthesis of Biologically Intriguing Cyclic Sulfonamides
Authors: Zimmermann Stefan , Akbarzadeh Mohammad , Otte Felix , Strohmann Carsten , Sankar Muthukumar Gomathi , Ziegler Slava , Pahl Axel , Sievers Sonja , Kumar Kamal
Published: September 2019

A “branching–folding” synthetic strategy that affords a range of diverse cyclic benzo‐sulfonamide scaffolds is presented. Whereas different annulation reactions on common ketimine substrates build the branching phase of the scaffold synthesis, a common hydrogenative ring‐expansion method, facilitated by an increase of the ring‐strain during the branching phase, led to sulfonamides bearing medium‐sized rings in a folding pathway. Cell painting assay was successfully employed to identify tubulin targeting sulfonamides as novel mitotic inhibitors.
Reactive Separations for In Situ Product Removal of Enzymatic Reactions: A Review
Authors: Fellechner Oliver , Blatkiewicz Michał , Smirnova Irina
Published: September 2019

The topic of integrating enzymatic reactions with in situ product removal is addressed. Different integrated reactive separations structured accordingly to the corresponding unit operations, i.e., reactive distillation, reactive chromatography, reactive crystallization, and extractive biocatalysis, are discussed. Special attention is given to their realization with homogenous and heterogeneous biocatalysis. Various enzyme immobilization techniques are presented and distinct strategies for installation of heterogeneous catalysts into process equipment are discussed.
Unsteady conjugate mass transfer of a 2D deformable droplet in a modest extensional flow in across‐slot
Authors: Liu Anjun , Chen Jie , Wang Zhenzhen , Wang Jingtao , Mao Zai‐Sha , Yang Chao
Published: September 2019

This work aims to investigate the unsteady conjugate interphase mass transfer between a stationary deformed drop and the modest extensional flow in a cross‐intersected 2D channel. It is very difficult to accurately quantify the transient mass transfer rate of solute in such a geometry. Therefore, we established a mathematical model on the basic of the Stokes equation and solved it by the boundary element method, which could deal precisely with a two‐phase flow system with a deformable interface; meanwhile, the convection‐diffusion equation was solved by the finite difference method to calculate the unsteady conjugate interphase mass transfer. The simulation results showed that the mass transfer rate, analyzed and characterized in terms of mean concentration variation and Sherwood number Sh, was affected by capillary number Ca, Peclet number Pe, viscosity ratio
λ, interior‐to‐exterior diffusivity ratio K, distribution coefficient m, and wall effect factor W.
Doubly sparse regression incorporating graphical structure among predictors
Authors: Stephenson Matthew , Ali R. Ayesha , Darlington Gerarda A. ,   for the Alzheimer's Disease Neuroimaging Initiative
Published: September 2019

Abstract

Recent research has demonstrated that information learned from building a graphical model on the predictor set of a regularized linear regression model can be leveraged to improve prediction of a continuous outcome. In this article, we present a new model that encourages sparsity at both the level of the regression coefficients and the level of individual contributions in a decomposed representation. This model provides parameter estimates with a finite sample error bound and exhibits robustness to errors in the input graph structure. Through a simulation study and the analysis of two real data sets, we demonstrate that our model provides a predictive benefit when compared to previously proposed models. Furthermore, it is a highly flexible model that provides a unified framework for the fitting of many commonly used regularized regression models. The Canadian Journal of Statistics 47: 729–747; 2019 © 2019 Statistical Society of Canada
A Hands‐On Guide to Brewing and Analyzing Beer in the Laboratory
Authors: Thesseling Florian A. , Bircham Peter W. , Mertens Stijn , Voordeckers Karin , Verstrepen Kevin J.
Published: September 2019

Beer would not exist without microbes. During fermentation, yeast cells convert cereal‐derived sugars into ethanol and CO2. Yeast also produces a wide array of aroma compounds that influence beer taste and aroma. The complex interaction between all these aroma compounds results in each beer having its own distinctive palette. This article contains all protocols needed to brew beer in a standard lab environment and focuses on the use of yeast in beer brewing. More specifically, it provides protocols for yeast propagation, brewing calculations and, of course, beer brewing. At the end, we have also included protocols for analyses that can be performed on the resulting brew, with a focus on yeast‐derived aroma compounds. © 2019 The Authors.
Synthesis and Photodynamics of Stilbenyl‐Azopyrroles: Two‐Photon Controllable Photoswitching Systems
Authors: Muñoz‐Rugeles Leonardo , Gallardo‐Rosas David , Durán‐Hernández Jesús , López‐Arteaga Rafael , Toscano R. Alfredo , Esturau‐Escofet Nuria , López‐Cortés José G. , Peón Jorge , Ortega‐Alfaro M. Carmen
Published: September 2019

Three new stilbenyl‐azopyrroles 3 a–c were synthesized through a Mizoroki‐Heck C−C‐type coupling reaction between the 2‐(4′‐iodophenyl‐azo)‐N‐methyl pyrrole (1), and three different para‐substituted styrene derivatives. Inclusion of additional NO2 and NMe2 groups at the para‐position of the stilbenyl section resulted in significant changes of their linear and non‐linear optical properties. The photoisomerization behavior was studied through ultrafast laser techniques for single‐ and two‐photon excitation. The time‐resolved studies indicate that, despite the drastic changes in conjugation, the typical path for photoisomerization is maintained in these systems for both single and biphotonic excitation. In particular, the NO2 substituted molecule showed improved two‐photon absorption capacities, together with a significant trans−cis isomerization channel, implying that the photoswitching process can be controlled with high spatial precision through non‐linear optical excitation.
A cluster‐based fault‐tolerant routing protocol for wireless sensor networks
Authors: Moussa Noureddine , El Belrhiti El Alaoui Abdelbaki
Published: September 2019

Energy conservation and fault tolerance are two critical issues in the deployment of wireless sensor networks (WSNs). Many cluster‐based fault‐tolerant routing protocols have been proposed for energy conservation and network lifetime maximization in WSNs. However, these protocols suffer from high frequency of re‐clustering as well as extra energy consumption to tolerate failures and consider only some very normal parameters to form clusters without any verification of the energy sufficiency for data routing. Therefore, this paper proposes a cluster‐based fault‐tolerant routing protocol referred as CFTR. This protocol allows higher energy nodes to become Cluster Heads (CHs) and operate multiple rounds to diminish the frequency of re‐clustering. Additionally, for the sake to get better energy efficiency and balancing, we introduce a cost function that considers during cluster formation energy cost from sensor node to CH, energy cost from CH to sink, and another significant parameter, namely, number of cluster members in previous round. Further, the proposed CFTR takes care of nodes, which have no CH in their communication range. Also, it introduces a routing algorithm in which the decision of next hop CH selection is based on a cost function conceived to select routes with sufficient energy for data transfer and distribute uniformly the overall data‐relaying load among the CHs. As well, a low‐overhead algorithm to tolerate the sudden failure of CHs is proposed. We perform extensive simulations on CFTR and compare their results with those of two recent existing protocols to demonstrate its superiority in terms of different metrics.
Intelligent threshold selection in fading environment of cognitive radio network: Advances in throughput and total error probability
Authors: Kumar Alok , Thakur Prabhat , Pandit Shweta , Singh Ghanshyam
Published: September 2019

One of the main challenges of spectrum sensing (SS) in the cognitive radio network (CRN) is selection of threshold for captivating the sensing decision, and such an issue becomes more challenging especially at low signal‐to‐noise ratio (SNR) because it affects the sensing performance and throughput of cognitive user (CU). However, the sensing decision of individual CU may not be accurate due to fading effects in the sensing environment, and significant improvement is accomplished with the cooperation of users. Therefore, in this paper, we have investigated the performance of energy detector SS (EDSS) technique in the CRN under fading environment with cooperative and noncooperative SS scenario. Further, we have introduced the concept of critical SNR (γc) to select the appropriate threshold and based on which the algorithms are proposed to enhance the throughput and reduce the total error (sensing error) probability of CU at different SNR (γ). From the results, we have accomplished that at the low SNR region (γ ≤ γc), throughput is maximum with constant false‐alarm rate (CFAR) threshold selection approach in the cooperative scenario while in the high SNR region (γ > γc), its value is maximum with minimizing the error probability (MEP) threshold selection approach in the noncooperative scenario. Moreover, the sensing error is reduced with cooperation, and threshold selection with MEP approach outperforms CFAR approach for γ ≤ γc. Further, the proposed approach outperforms the other approaches in terms of throughput and sensing error (total error) probability in the Rayleigh and Nakagami‐m fading environments.
Spatiotemporal effects of logging and fire on tall, wet temperate eucalypt forest birds
Authors: Lindenmayer David B. , Blanchard Wade , Blair David , Westgate Martin J. , Scheele Ben C.
Published: September 2019

Forests globally are subject to disturbances such as logging and fire that create complex temporal variation in spatial patterns of forest cover and stand age. However, investigations that quantify temporal changes in biodiversity in response to multiple forms of disturbance in space and time are relatively uncommon. Over a 10‐yr period, we investigated the response of bird species to spatiotemporal changes in forest cover associated with logging and wildfire in the mountain ash (Eucalyptus regnans) forests of southeastern Australia. Specifically, we examined how bird occurrence changed with shifts in the proportion of area burned or logged in a 4.5 km radius surrounding our 88 long‐term field survey sites, each measuring 1 ha in size. Overall species richness was greatest in older forest patches, but declined as the amount of fire around each site increased. At the individual species level, 31 of the 37 bird species we modeled exhibited a negative response to the amount of fire in the surrounding landscape, while one species responded positively to fire. Only nine species exhibited signs of recovery in the 6 yr of surveys following the fire. Five species were more likely to be detected as the proportion of logged forest surrounding a site increased, suggesting a possible “concentration effect” with displaced birds moving into unlogged areas following harvesting of adjacent areas. We also identified relationships between the coefficients of life history attributes and spatiotemporal changes in forest cover and stand age. Large‐bodied birds and migratory species were associated with landscapes subject to large amounts of fire in 2009. There were associations between old growth stands and small‐bodied bird species and species that were not insectivores. Our study shows that birds in mountain ash forests are strongly associated with old growth stands and exhibit complex, time‐dependent, and species‐specific responses to landscape disturbance. Despite logging and fire both being high‐severity perturbations, no bird species exhibited similar responses to fire and logging in the landscape surrounding our sites. Thus, species responses to one kind of landscape‐scale disturbance are not readily predictable based on an understanding of the responses to another kind of (albeit superficially similar) disturbance.
Extensive genetic differentiation between recently evolved sympatric Arctic charr morphs
Authors: Guðbrandsson Jóhannes , Kapralova Kalina H. , Franzdóttir Sigríður R. , Bergsveinsdóttir Þóra Margrét , Hafstað Völundur , Jónsson Zophonías O. , Snorrason Sigurður S. , Pálsson Arnar
Published: September 2019

The availability of diverse ecological niches can promote adaptation of trophic specializations and related traits, as has been repeatedly observed in evolutionary radiations of freshwater fish. The role of genetics, environment, and history in ecologically driven divergence and adaptation, can be studied on adaptive radiations or populations showing ecological polymorphism. Salmonids, especially the Salvelinus genus, are renowned for both phenotypic diversity and polymorphism. Arctic charr (Salvelinus alpinus) invaded Icelandic streams during the glacial retreat (about 10,000 years ago) and exhibits many instances of sympatric polymorphism. Particularly, well studied are the four morphs in Lake Þingvallavatn in Iceland. The small benthic (SB), large benthic (LB), planktivorous (PL), and piscivorous (PI) charr differ in many regards, including size, form, and life history traits. To investigate relatedness and genomic differentiation between morphs, we identified variable sites from RNA‐sequencing data from three of those morphs and verified 22 variants in population samples. The data reveal genetic differences between the morphs, with the two benthic morphs being more similar and the PL‐charr more genetically different. The markers with high differentiation map to all linkage groups, suggesting ancient and pervasive genetic separation of these three morphs. Furthermore, GO analyses suggest differences in collagen metabolism, odontogenesis, and sensory systems between PL‐charr and the benthic morphs. Genotyping in population samples from all four morphs confirms the genetic separation and indicates that the PI‐charr are less genetically distinct than the other three morphs. The genetic separation of the other three morphs indicates certain degree of reproductive isolation. The extent of gene flow between the morphs and the nature of reproductive barriers between them remain to be elucidated.
Controlling factors affecting the presence and distribution of Didymosphenia geminata in lakes and rivers of the Neuquén province, Argentina
Authors: Beamud Sara Guadalupe , Laffitte Lorena , Muñiz Saavedra Julieta , Baffico Gustavo , Laurenzano Betina , Diaz Mónica , Pedrozo Fernando
Published: September 2019

The diatom Didymosphenia geminata (D. geminata) is an invasive periphytic species from the Northern Hemisphere. D. geminata occurrence and mat formation in Patagonia Argentina dates from 2010, spreading throughout Patagonia (provinces of Chubut, Neuquén, Río Negro, and Santa Cruz) by 2017. In 2012, the Surveillance and Monitoring Program was implemented by Neuquén government entities. Within this programme, nine sampling campaigns have been conducted at 91 sites including streams, rivers, lakes, reservoirs, and a canal. Presence or absence of D. geminata cells, abundance of D. geminata and other algal species cells as well as environmental variables were determined in samples. Multivariate analysis and generalized linear models were used to determine environmental constraints on habitat suitability and requirements for D. geminata. During 2012–2017, D. geminata cells were detected at 33 out of 91 sites sampled. D. geminata was present in lower streams order, with low values of total and dissolved nutrients, conductivity, alkalinity, ions and solutes, and high values of dissolved oxygen and habitat quality, for the ranges of environmental variables measured at sampling sites. D. geminata abundance was negatively related to stream order. Our results prove that D. geminata is expanding its ecological spectrum, showing a wider tolerance to environmental conditions particularly for phosphorus and nitrogen, some ions such as magnesium, and even temperature, and they confirm some authors' hypothesis about the ecological behaviour of this invasive species. Range expansion and environmental preferences of D. geminata could modify the state of susceptibility to invasion in numerous waterbodies.
CuI/CuII Complexes with Dipicolinoylbis(N,N‐diethylthiourea): Structures, Magnetism, and Guest Ion Exchange
Authors: Pham Chien Thang , Nguyen Thu Ha , Matsumoto Kenji , Nguyen Hung Huy
Published: September 2019

Potassium cations play a vital role in directing reactions of 2,6‐dipicolinoylbis(N,N‐diethylthiourea) (H2L) with Cu(OAc)2. In the absence of K+, a redox reaction occurred, leading to the formation of a polymeric complex [CuIICuI2(L)2]∞ (1). On the other hand, adding a K+ source (i.e KPF6) directs the reaction to a self‐assembly process, forming the {2}‐metallacoronate [CuII2K(L)2](PF6) (2) complexes. The polymeric structure of 1 is built by bridging neighboring [CuIICuI2(L)2] units via Cu2S2 linkages. The supramolecular structure of 2 is constructed by weak interactions between planar [CuII2K(L)2]+ substructures. Cryomagnetic measurements reveal antiferromagnetic interactions between two CuII centers in the same sub‐unit and ferromagnetic interactions between CuII centers of the neighboring sub‐units. The guest K+ cation exchange study for 2 suggests the formation of the [CuII2M(L)2](PF6) series in CH2Cl2 (M = Li, Na, K, Rb and Cs). The stability of the complexes decreases in the order [CuII2K(L)2]+ > [CuII2Na(L)2]+ > [CuII2Rb(L)2]+ > [CuII2Cs(L)2]+ > [CuII2Li(L)2]+.
Multicomponent Synthesis of 2‐Arylvinyl‐Substituted Fulleropyrrolidines from [60]Fullerene, Amines and Aldehydes
Authors: Niu Chuang , Chen Xiao‐Ping , Yin Zheng‐Chun , Wang Guan‐Wu
Published: September 2019

The three‐ and four‐component reactions of [60]fullerene with triethylamine/diethylamine and aldehydes affording 2‐arylvinyl‐substituted fulleropyrrolidines in high stereoselectivity have been achieved. Depending on the reaction conditions, cis‐ and trans‐fulleropyrrolidines can be stereoselectively synthesized. The thermodynamically stable cis‐fulleropyrrolidines can be obtained by rearrangement of the kinetically formed trans‐fulleropyrrolidines. A plausible reaction mechanism is proposed to elucidate the formation of fulleropyrrolidines.
Biomorphological scaling laws from convectively accelerated streams
Authors: Calvani Giulio , Perona Paolo , Schick Coralie , Solari Luca
Published: September 2019

Worldwide convectively accelerated streams flowing in downstream‐narrowing river sections show that riverbed vegetation growing on alluvial sediment bars gradually disappears, forming a front beyond which vegetation is absent. We revise a recently proposed analytical model able to predict the expected longitudinal position of the vegetation front. The model was developed considering the steady state approximation of 1‐D ecomorphodynamics equations. While the model was tested against flume experiments, its extension and application to the field is not trivial as it requires the definition of proper scaling laws governing the observed phenomenon. In this work, we present a procedure to calculate vegetation parameters and flow magnitude governing the equilibrium at the reach scale between hydromorphological and biological components in rivers with converging boundaries. We collected from worldwide rivers data of section topography, hydrogeomorphological and riparian vegetation characteristics to perform a statistical analysis aimed to validate the proposed procedure. Results are presented in the form of scaling laws correlating biological parameters of growth and decay from different vegetation species to flood return period and duration, respectively. Such relationships demonstrate the existence of underlying selective processes determining the riparian vegetation both in terms of species and cover. We interpret the selection of vegetation species from ecomorphodynamic processes occurring in convectively accelerated streams as the orchestrated dynamic action of flow, sediment and vegetation characteristics. © 2019 John Wiley & Sons, Ltd.