bluuebunny/crossref_metadata_2025 huggingface dataset:
Holographic Image Denoising using Random Laser Illumination
Authors: Mallick Subha Prakash , Sung Zson
Published: October 2020

In holographic applications, coherent lasers are indispensable source of illumination. Despite high intensity from coherent light sources, they fail in full‐field image projection and illustrate speckle images due to high spatial coherence. This article demonstrates speckle‐free high contrast computer‐generated holographic image projection upon illumination with a perovskite–polystyrene 10 wt%‐based random laser. Solvent‐engineered efficient and durable perovskite and perovskite–polystyrene 10 wt%‐based random lasers are fabricated. Optical characterizations are elucidated and controlled coherence random lasing operation is achieved under room temperature upon addition of polystyrene concentration 10 wt% on perovskite thin film. The addition of 10 wt% polystyrene concentration results in a low far‐field divergence angle of ≈100. The controlled coherence in random lasers is necessary to produce a stable interference pattern and to retain the depth of field in holograms. Additionally, the holographic image projection using random lasers reduces diffraction noise, and exhibits high spatial resolution with full‐field imaging. Moreover, this study is clear evidence of an effective strategy to achieve high‐performance, indigenous designed‐controlled coherence in disordered random lasing media and its application to novel holographic image projection.
Alkalimetall‐Mediatoren: Vielfältige Anwendungen in der metallorganischen Chemie der Hauptgruppenelemente
Authors: Gentner Thomas X. , Mulvey Robert E.
Published: October 2020

Organolithiumverbindungen stehen seit mehr als einem Jahrhundert an der Spitze der Synthesechemie, da sie die Synthese von einer Vielzahl von Verbindungen ermöglichen, die weltweit im akademischen und industriellen Bereich eingesetzt werden. Aus diesem Grund ist Lithium seit jeher das wichtigste Alkalimetall in der metallorganischen Chemie. Heute wird diese Dominanz durch Natrium und Kalium ernsthaft infrage gestellt, da sich die Verwendung von Alkalimetallen in der organischen Chemie zu einer großen Vielfalt entwickelt hat. In diesem Aufsatz werden jüngste Beispiele aus verschiedenen Bereichen aufgegriffen, wie die homogene Katalyse der Hauptgruppenmetalle, stöchiometrische Reaktionen in der organischen Synthese, der niedervalenten Hauptgruppenmetallchemie, der Polymerchemie und der grünen, nachhaltigen Chemie. Da Alkalimetallverbindungen oft nicht die Endprodukte dieser Anwendungen sind, wird ihre Rolle nur selten in den Vordergrund gestellt oder gar nicht beachtet. Dieser Bericht wurde verfasst, um die wissenschaftliche Gemeinde auf das immer bedeutender werdende Phänomen der “Alkalimetall‐Mediation” aufmerksam zu machen.
Die krankheitsassoziierte Tau‐Phosphorylierung behindert die Tubulinpolymerisation in Tau‐Kondensaten
Authors: Savastano Adriana , Flores David , Kadavath Harindranath , Biernat Jacek , Mandelkow Eckhard , Zweckstetter Markus
Published: October 2020

Die zelluläre Kondensation von intrinsisch ungeordneten Proteinen (IDPs) durch Flüssig‐flüssig‐Phasentrennung (LLPS) ermöglicht die dynamische Kompartimentierung und Regulation biologischer Prozesse. Das IDP Tau, das den Aufbau von Mikrotubuli fördert und bei der Alzheimer‐Krankheit hyperphosphoryliert wird, kann in Lösung und auf der Oberfläche von Mikrotubuli LLPS‐Prozesse durchlaufen. Der Einfluss der Tau‐Phosphorylierung auf Tau‐LLPS‐vermittelte Tubulinpolymerisation ist jedoch weitestgehend unbekannt. Wir zeigen hier, dass unmodifiziertes Tau sowie an krankheitsassoziierten Epitopen phosphoryliertes Tau zu flüssigkeitsähnlichen Tröpfchen kondensieren. Obwohl sich Tubulin in allen Tau‐Tröpfchen in hohen Konzentrationen anreichert, ist es nicht in der Lage, aus dem Inneren von Tröpfchen, die durch am AT180‐Epitop phosphoryliertes Tau (T231/S235) gebildet wurden, zu Mikrotubuli zu wachsen. Im Gegensatz dazu hemmte weder die Phosphorylierung von Tyrosinresten in Tau noch die Phosphorylierung in der Repeatdomäne die Polymerisation von Tubulin aus Tau‐Tröpfchen. Da gezeigt wurde, dass LLPS von IDPs verschiedene Arten der Zytoskelettassemblierung fördert, legt unsere Studie nahe, dass die IDP‐Phosphorylierung ein weit verbreiteter Mechanismus für die Regulation der kondensatvermittelten Zytoskelettassemblierung sein könnte.
Alkali‐Metal Mediation: Diversity of Applications in Main‐Group Organometallic Chemistry
Authors: Gentner Thomas X. , Mulvey Robert E.
Published: October 2020

Organolithium compounds have been at the forefront of synthetic chemistry for over a century, as they mediate the synthesis of myriads of compounds that are utilised worldwide in academic and industrial settings. For that reason, lithium has always been the most important alkali metal in organometallic chemistry. Today, that importance is being seriously challenged by sodium and potassium, as the alkali‐metal mediation of organic reactions in general has started branching off in several new directions. Recent examples covering main‐group homogeneous catalysis, stoichiometric organic synthesis, low‐valent main‐group metal chemistry, polymerization, and green chemistry are showcased in this Review. Since alkali‐metal compounds are often not the end products of these applications, their roles are rarely given top billing. Thus, this Review has been written to alert the community to this rising unifying phenomenon of “alkali‐metal mediation”.
Stretching and rupture of a viscous liquid bridge between two spherical particles
Authors: Li Xiangqi , Wang Dengfei , Huang Fenglei , Cai Ziqi , Gao Zhengming
Published: October 2020

In this paper, the stretching and rupture of liquid bridge are studied by experiment and numerical simulation. In the experiment, the relationship between the critical rupture distance of the liquid bridge and four factors, including volume of liquid bridge, particle initial distance, liquid bridge stretching velocity and liquid bridge viscosity, is quantitatively studied. It is found that the liquid bridge critical rupture distance can be described by the modified Bond number, where the critical distance shows a maximum value when this number is about 0.6. As the Capillary number of liquid bridge increases, the effect of the liquid bridge stretching velocity on the critical rupture distance increases, while the influence of the liquid bridge viscosity on the critical rupture distance increases with the volume of liquid bridge. Mesh overset is used to describe the profile change of liquid bridge, and based on the simulation the pressure field is applied in calculating the capillary fore in the liquid bridge. The rupture energy of liquid bridge can be mainly related with the Capillary number, showing two different functions when Ca = 0.01 is the turning point. Finally, two empirical formulas are proposed to predict the rupture energy of liquid bridge.
Compatibilization of epoxidized triblock copolymer on the generation of self‐assembled nanostructured epoxies and their surface wettability
Authors: Remya Vasudevan Pillai R. , Jose Varghese Rajendran , Parani Sundararajan , Sakho El Hadji Mamour , Oluwafemi Oluwatobi S. , Thomas Sabu
Published: October 2020

In this work, we have successfully synthesized epoxidized poly(styrene‐block‐butadiene‐block‐styrene) with the highest epoxidation degree (55 mol%) for the first time by using metachloroperbenzoic acid method. This highly epoxidized styrene‐butadiene‐styrene (eSBS) block copolymer exhibited good compatibility with the epoxy (diglycidylether of bisphenol‐A)/ eSBS block copolymer‐ 4,4′‐diamino diphenyl methane blend. Transmission electron microscope images showed that the eSBS block copolymer formed spherical nanostructure morphology within the blend due to reaction induced phase separation. The addition of eSBS block copolymer in the system significantly improved the wetting parameters such as hydrophilicity, surface free energy, work of adhesion, spreading coefficient and Girifalco‐Good's interaction parameter values, which are discussed in detail. The as‐prepared self‐assembled nanostructured epoxy system will be useful in highly toughened coating applications such as aircraft, automobile, and flooring industries.
Scarring patterns of whale sharks, Rhincodon typus, at a provisioning site in the Philippines
Authors: Penketh Luke , Schleimer Anna , Labaja Jessica , Snow Sally , Ponzo Alessandro , Araujo Gonzalo
Published: October 2020

Shark‐based tourism continues to be a rapidly growing industry, and thus understanding the impacts of such activities is essential to mitigate the potential negative effects on the target species. The consequences of provisioning on whale sharks (Rhincodon typus) are not fully understood, although changes to the local environment, ecology, behaviour, and site visitation patterns have been highlighted. Here, the scarring patterns of whale sharks were investigated at a provisioning site in Oslob, Cebu, Philippines, as an indicator of the physical impacts of tourism activities on individual sharks. Photographic identification was used to attribute scars to individual animals (n = 152) between March 31, 2012 and January 31, 2015.

Scars were categorized by type and body location, and were compared with non‐provisioned aggregations in Australia, Mozambique, and Seychelles. Oslob whale sharks were more scarred than other studied populations, with 94.7% (n = 144) having at least one scar, and with 90.8% (n = 138) having more than one scar. Scarring incidence was found to be significantly higher in sharks that regularly visited the provisioning site, and analysis of scarring over time in highly resident sharks showed that all individuals gained scars through periods of consistent re‐sightings. A significantly higher incidence of minor scar types was found, most commonly on the dorsal side of the animal, probably resulting from sustained proximity to boats and ropes throughout the provisioning activities. The consequences of interactions with propeller boats were observed, despite a ban on their use in the provisioning site, highlighting the risk to the species beyond the study site.

We recommend the strict enforcement of a minimum distance between boats and sharks, a zero‐contact policy during interactions, the expansion of the provisioning site, and the implementation of a no‐boat‐access zone around the perimeter of the provisioning site to mitigate potential collisions.
Development, structure, and protein composition of reptilian claws and hypotheses of their evolution
Authors: Alibardi Lorenzo
Published: October 2020

Here, we review the development, morphology, genes, and proteins of claws in reptiles. Claws likely form owing to the inductive influence of phalangeal mesenchyme on the apical epidermis of developing digits, resulting in hyperproliferation and intense protein synthesis in the dorsal epidermis, which forms the unguis. The tip of claws results from prevalent cell proliferation and distal movement along most of the ungueal epidermis in comparison to the ventral surface forming the subunguis. Asymmetrical growth between the unguis and subunguis forces beta‐cells from the unguis to rotate into the apical part of the subunguis, sharpening the claw tip. Further sharpening occurs by scratching and mechanical wearing. Ungueal keratinocytes elongate, form an intricate perimeter and cementing junctions, and remain united impeding desquamation. In contrast, thin keratinocytes in the subunguis form a smooth perimeter, accumulate less corneous beta proteins (CBPs) and cysteine‐poor intermediate filament (IF)‐keratins, and desquamate. In addition to prevalent glycine–cysteine–tyrosine rich CBPs, special cysteine‐rich IF‐keratins are also synthesized in the claw, generating numerous SS bonds that harden the thick and compact corneous material. Desquamation and mechanical wear at the tip ensure that the unguis curvature remains approximately stable over time. Reptilian claws are likely very ancient in evolution, although the unguis differentiated like the outer scale surface of scales, while the subunguis might have derived from the inner scale surface. The few hair‐like IF‐keratins synthesized in reptilian claws indicate that ancestors of sauropsids and mammals shared cysteine‐rich IF‐keratins. However, the number of these keratins remained low in reptiles, while new types of CBPs function to strengthen claws.
Vertebral pattern variation in the North Sea harbor porpoise (Phocoena phocoena) by computed tomography
Authors: Willems Dorien S. , IJsseldijk Lonneke L. , van den Broek D. Hendrik N. , Veraa Stefanie
Published: October 2020

Vertebral series in the harbor porpoise (Phocoena phocoena) include cervical, thoracic, lumbar, and caudal. In contrast to studying skeletons from museums, in which small bones can be missed, evaluation of full body computed tomography (CT) scans provides an overview of the vertebral column, while maintaining interrelationship of all structures. The aim of this study was to document variations in vertebral patterning of the harbor porpoise via evaluation of CT images of intact stranded harbor porpoises. The harbor porpoises were divided into age classes, based on developmental stage of reproductive organs on postmortem examination and closure of proximal humeral physis on CT. Numbers of vertebrae per series, fusion state of the syncervical, type of first hemal arch, number of double articulating ribs, and floating ribs were recorded based on CT images. Included in the study were 48 harbor porpoises (27 males and 21 females), which were divided in two age classes (27 immatures and 21 adults). Total vertebral count varied from 63 to 68 with vertebral formula range C7T12‐14L12‐16Cd29‐33. Twenty‐five different vertebral formulas were found, of which C7T13L14Ca30 was the most common (n = 8, 17%). Thoracic vertebrae with six, seven, or eight double articulating ribs and zero, one, or two vertebrae with floating ribs were seen. Four different fusion states of the syncervical and four types of hemal arches were recognized. This study showed a great variation in vertebral patterning in the harbor porpoise, with homeotic and meristic variation in the thoracic, lumbar, and caudal vertebral series.
Metal‐Catalyzed Spiroannulation‐Fluoromethylfunctionaliztions of 1,5‐Enynes for the Synthesis of Stereodefined (Z)‐Spiroindenes
Authors: Zuo Hang‐Dong , Cui Chen‐Chang , Guo Cheng , Hao Wen‐Juan , Tu Shu‐Jiang , Jiang Bo
Published: October 2020

Two classes of new catalytic spiroannulation‐fluormethylfunctionaliztions of para‐quinone methide (p‐QM)‐containing 1,5‐enynes have been established under redox‐neutral conditions. Palladium‐catalyzed spiroannulation‐iododifluoromethylation with ethyl difluoroiodoacetate oriented completely stereoselective access to (Z)‐spiroindenes and the latter included copper‐catalyzed three‐component spiroannulation‐cyanotrifluoromethylation starting from Togni's reagent and trimethylsilanecarbonitrile (TMSCN). Both reaction pathways involve fluoroalkyl radical‐triggered 1,6‐addition/5‐exo‐dig annulation/metal radical cross‐coupling/reductive elimination sequence, providing practical and stereoselective protocols for rapidly constructing cyclohexadienone‐containing spiroindenes with generally good yields.
Frontoparietal Network in Executive Functioning in Autism Spectrum Disorder
Authors: May Kaitlyn E. , Kana Rajesh K.
Published: October 2020

Higher cognitive functions in autism spectrum disorder (ASD) are characterized by impairments in executive functions (EF). While some research attributes this to an overreliance of the prefrontal cortex (PFC), others demonstrate poor recruitment of the PFC in individuals with ASD. In order to assess the emerging consensus across neuroimaging studies of EF in ASD, the current study used a coordinate‐based activation likelihood estimation (ALE) analysis of 16 functional magnetic resonance imaging (fMRI) studies, resulting in a meta‐analysis of data from 739 participants (356 ASD, 383 typically developing [TD] individuals) ranging from 7 to 52 years of age. Within‐group analysis of EF tasks revealed that both TD and ASD participants had significant activity in PFC regions. Analysis of group differences indicated greater activation in ASD, relative to TD participants, in the right middle frontal gyrus and the anterior cingulate cortex, and lesser activation in the bilateral middle frontal, left inferior frontal gyrus, right inferior parietal lobule, and precuneus. Although both ASD and TD participants showed similar PFC activation, there was differential recruitment of wider network of EF regions such as the IPL in ASD participants. The under‐recruitment of parietal regions may be due to poor connectivity of the frontoparietal networks with other regions during EF tasks or a restricted executive network in ASD participants which is limited primarily to the PFC. These results support the executive dysfunction hypothesis of ASD and suggests that poor frontoparietal recruitment may underlie some of the EF difficulties individuals with ASD experience.

Lay Summary

This study reports a meta‐analysis of 16 brain imaging studies of executive functions (EF) in individuals with autism spectrum disorder (ASD). While parts of the brain's EF network is activated in both ASD and control participants, the ASD group does not activate a wider network of EF regions such as the parietal cortex. This may be due to poor EF network connectivity, or a constrained EF network in ASD participants. These results may underlie some of the EF difficulties individuals with ASD experience. Autism Res 2020, 13: 1762–1777. © 2020 International Society for Autism Research and Wiley Periodicals LLC
Economic impact of yield and composition variation in bioenergy crops: Populus trichocarpa
Authors: Happs Renee M. , Bartling Andrew W. , Doeppke Crissa , Harman‐Ware Anne E. , Clark Robin , Webb Erin G. , Biddy Mary J. , Chen Jin‐Gui , Tuskan Gerald A. , Davis Mark F. , Muchero Wellington , Davison Brian H.
Published: October 2020

To achieve a bio‐based economy, it is necessary to consider variability within a feedstock population. We must understand the range of key phenotypic characteristics when selecting economically advantageous genotypes for domestication in an optimized supply chain. In this analysis we measured cell‐wall composition traits in a large natural variant population of Populus trichocarpa. The results were combined with agronomic growth data from the matching genotype to conduct various techno‐economic analyses, evaluating the impacts of physical and compositional variability and determining the ultimate phenotypic drivers for yield and economic metrics. Here we show that, although ethanol yield per land area per year and minimum fuel selling price were most strongly impacted by tree size, when considering the largest 25% of trees, size and carbohydrate content were nearly identical influences on minimal fuel selling price, highlighting the need to focus on both size and carbohydrate content in selecting economically optimal feedstocks. © 2020 The Authors. Biofuels, Bioproducts, and Biorefining published by Society of Chemical Industry and John Wiley & Sons, Ltd
Hydrogel microfluidic‐based liver‐on‐a‐chip: Mimicking the mass transfer and structural features of liver
Authors: Meng Qin , Wang Ying , Li Yingjun , Shen Chong
Published: October 2020

Liver is fed by nutrition via diffusion across the vascular wall from blood flow. However, hepatocytes in liver models are directly exposed to the perfusion culture medium, where the shear stress reduces the cell viability and liver‐specific functions. By mimicking the mass transfer and structural features of hepatic lobule, we designed a microfluidic liver‐on‐a‐chip based on the di‐acrylated pluronic F127 hydrogel. In the hydrogel chip, hepatocellular carcinoma HepG2 and human hepatic stellate cell LX‐2 were statically cultured inside the microwells on the outer channel. These hepatic cells were fed by the diffused medium from the adjacent but separated inner channel with endothelial cell monolayers, which was perfused by the medium with physiologically relevant shear stress. As found, the hepatic cells in the liver‐on‐a‐chip rapidly formed spheroids within 1‐day incubation and expressed about one to two‐fold higher viability/liver‐specific functions than the corresponding static culture for at least 8 days. Moreover, the presence of endothelial cells also contributed to the expression of liver‐specific functions in the liver‐on‐a‐chip. Therefore, the proposed liver‐on‐a‐chip provides a new concept for construction of 3D liver models in vitro, and shows the potential value for a variety of applications including bio‐artificial livers and drug toxicity screening.
Biocathode design with highly‐oriented immobilization of multi‐copper oxidase from Pyrobaculum aerophilum onto a single‐walled carbon nanotube surface via a carbon nanotube‐binding peptide
Authors: Sakamoto Hiroaki , Futamura Rie , Tonooka Aina , Takamura Eiichiro , Satomura Takenori , Suye Shin‐ichiro
Published: October 2020

Biofuel cells generate electric energy using an enzyme as a catalyst for an electrode but their stability and low battery output pose problems for practical use. To solve these problems, this study aimed to build a long‐lasting and high‐output biocathode as a catalyst using a highly stable hyperthermophilic archaeal enzyme, multi‐copper oxidase, from Pyrobaculum aerophilum (McoP). To increase output, McoP was oriented and immobilized on single‐walled carbon nanotubes (SWCNT) with a high specific surface area, and the electrode interface was designed to achieve highly efficient electron transfer between the enzyme and electrode. Type 1 copper (T1Cu), an electron‐accepting site in the McoP molecule, is located near the C‐terminus. Therefore, McoP was prepared by genetically engineering a CNT‐binding peptide with the sequence LLADTTHHRPWT, at the C‐terminus of McoP (McoP‐CBP). We then constructed an electrode using a complex in which McoP‐CBP was aligned and immobilized on SWCNT, and then clarified the effect of CBP. The amounts of immobilized enzymes on McoP‐SWCNT and (McoP‐CBP)‐SWCNT complexes were almost equal. CV measurement of the electrode modified with both complexes showed 5.4 times greater current density in the catalytic reaction of the (McoP‐CBP)‐SWCNT/GC electrode than in the McoP‐SWCNT/GC electrode. This is probably because CBP fusion immobilize the enzyme on SWCNTs in an orientational manner, and T1Cu, the oxidation–reduction site in McoP, is close to the electrode, which improves electron transfer efficiency.
Know how to manage face‐mask branding in the time of COVID‐19
Authors: Faruque Zinnia
Published: October 2020

Whether displayed on a school sweatshirt, a baseball cap, or the increasingly ubiquitous staple of everyday wardrobe — a face mask — a school's name and logo are among its most valuable assets. The name and logo of a school and its athletic teams convey the school's brand, with the school's goodwill and reputation at stake. However, with mask sales now booming, there is an increased risk for the proliferation of the unauthorized sale of masks bearing a school's name or logo. Thus, even though colleges and universities across the country are in flux with their reopening plans, with many on‐campus activities, including collegiate sports, temporarily postponed, schools should remain vigilant about protecting their brands during the pandemic.
Feasibility of the novel proximal superficial femoral artery puncture technique to recanalize chronic total occlusions
Authors: Fukagawa Tomoya , Mori Shinsuke , Hirano Keisuke
Published: October 2020

Chronic total occlusion (CTO) of the superficial femoral artery (SFA) with flush occlusion is sometimes difficult to be treated by endovascular treatment (EVT). The guidewire could not pass the proximal cap because the entry of the CTO could not be detected by angiography. Thus, a retrograde approach is considered; however, there was a risk of jeopardizing the adjacent deep femoral artery by subintimal angioplasty. Moreover, the retrograde approach is not feasible when the distal artery could not be punctured because of stenosis, occlusion, or uncomfortable positioning for patients during EVT. Therefore, we considered a novel technique to overcome this problem, called the Proximal superficial femoral Artery Puncture to RecanalIze the Chronic totAl occlusion (PAPRICA) technique. In this technique, to establish wire externalization, a retrograde puncture was performed from the proximal site of the SFA‐CTO under ultrasound guidance, and the guidewire was advanced retrogradely from the puncture needle via the CTO site. After wire externalization, the guide catheter could be advanced into the SFA ostium. By pulling up the externalization wire, a strong backup and improved coaxial alignment of the guide catheter were achieved. This report presents two successful cases of flush SFA‐CTO using this novel technique.
Influence of Surface Formate Species on Methane Selectivity for Carbon Dioxide Methanation over Nickel Hydroxyapatite Catalyst
Authors: Wai Ming Hui , Ashok Jangam , Dewangan Nikita , Das Sonali , Xi Shibo , Borgna Armando , Kawi Sibudjing
Published: October 2020

Absence of mechanistic understanding of carbon dioxide (CO2) methanation reaction on nickel hydroxyapatite (NiHAP) and the nature of nickel chemical state hampers the enhancement of catalytic activity and selectivity for such material. A varying amount of oleic acid (OA) addition on NiHAP is found to have a strong influence on the chemical state of nickel as evidenced from x‐ray spectroscopy (XPS) and x‐ray absorption spectroscopy (XAS). The chemical state of nickel influences the amount of surface intermediate species which affects methane formation as observed in infra‐red spectroscopy. This suggests that varying amount of OA can influence the chemical state of nickel which is important in influencing the type of reaction intermediates on the NiHAP surface. Langmuir‐Hinshelwood model is validated for proposed reaction mechanism for the better performing catalyst. The findings reported here is useful for designing a hydroxyapatite‐based catalyst for CO2 utilization.
Recent Advances in Electrochemical CO2 Reduction on Indium‐Based Catalysts
Authors: Li Jiayu , Zhu Minghui , Han Yi‐Fan
Published: October 2020

Electrochemical reduction of CO2 (CO2RR) is a promising solution to mitigate the ever‐increasing global carbon emission. Indium‐based catalysts have been extensively studied for catalyzing the production of formate, CO, and even multi‐carbon molecules from CO2. Rational design of the catalyst, however, is urgently needed to further improve the activity, selectivity, and stability for the sake of commercialization. Herein, we comprehensively reviewed recent progresses on the indium based CO2RR catalysts. Specifically, aspects regarding the nature of active sites, reaction mechanism, and the impact of operating conditions are overviewed. The reported indium‐based monometallic and bimetallic catalysts in the literature are summarized, as well. Future directions should be focused on the understanding of catalyst system during the reaction and under industrial‐relevant conditions.
Structure, Properties, and Electrochemical Sensing Applications of Graphene‐Based Materials
Authors: da Silva Alexsandra D. , Paschoalino Waldemir J. , Damasceno João Paulo V. , Kubota Lauro T.
Published: October 2020

Owing to their versatility and unique characteristics, graphene‐based materials have been used extensively for the development of electrochemical sensors and biosensors. The key to the maximum potential of these materials is the understanding of the role their structure plays in their modification processes. Herein, we summarize some structural characteristics of graphene oxide (GO) and reduced graphene oxide (rGO) and explore different surface modification methods for electrochemical sensing applications. surveyed the most recent applications of these materials as (bio)sensors, particularly for environmental monitoring and health‐related applications, such as quantification of biomarkers and metabolites and detection of cancer cells. The low detection limits, selectivity toward target molecules, and robustness of GO‐ and rGO‐based electrodes render them critical materials for the preparation of sensors for routine analysis and monitoring.
Electrochemical Characterisation of Co@Co(OH)2 Core‐Shell Nanoparticles and their Aggregation in Solution
Authors: Xie Ruo‐Chen , Batchelor‐McAuley Christopher , Rauwel Erwan , Rauwel Protima , Compton Richard G.
Published: October 2020

Core‐shell Co@Co(OH)2 nanoparticles are characterised electrochemically with particular focus on the thin shell of cobalt (II) hydroxide which stabilises the metallic cobalt core against further oxidation in the presence of air. Voltammetric characterisation allows insights into the nature of the shell so both complementing and providing information unavailable using electron microscopy and X‐ray diffraction. Moreover, the electrode reactions, occurring at particle ensembles, of the further oxidation of surface Co(OH)2 to CoOOH under alkaline conditions are further evidenced at the single particle level using electrochemical particle‐electrode impacts (or ‘nano‐impacts’). On this basis, the large extent of particle agglomeration/aggregation of Co@Co(OH)2 nanoparticles while suspended in the solutions is inferred.
Purified Butanol from Lignocellulose – Solvent‐Impregnated Resins for an Integrated Selective Removal
Authors: Tippkötter Nils , Roth Jasmine
Published: October 2020

In traditional microbial biobutanol production, the solvent must be recovered during fermentation process for a sufficient space‐time yield. Thermal separation is not feasible due to the boiling point of n‐butanol. As an integrated and selective solid‐liquid separation alternative, solvent impregnated resins (SIRs) were applied. Two polymeric resins were evaluated and an extractant screening was conducted. Vacuum application with vapor collection in fixed‐bed column as bioreactor bypass was successfully implemented as butanol desorption step. In course of further increasing process economics, fermentation with renewable lignocellulosic substrates was conducted using Clostridium acetobutylicum. Utilization of SIR was shown to be a potential strategy for solvent removal from fermentation broth, while application of a bypass column allows for product removal and recovery at once.
Chirale Pinene im Regenwald
Authors: Fischer‐Henningsen Doris
Published: October 2020

Wälder geben große Mengen biogener flüchtiger organischer Verbindungen an die Atmosphäre ab. Viele davon, wie α‐Pinen (Abbildung 1), sind chiral. Nun entdeckte ein Forscherteam am Messturm ATTO im Amazonas‐Regenwald, dass das Verhältnis der enantiomeren Pinene anders als erwartet nicht konstant ist, sondern variiert.
Service evaluation through FH‐entropy method: A framework for the elderly care station
Authors: Li Aihua , Wang Diwen , Zhu Meihong
Published: October 2020

The elderly care station is a new concept, which is the terminal service institution of the home‐based elderly care system in Beijing. Because its supervision of service quality (SQ) is not standardized and its current subsidy is irrelevant to SQ, this paper provides a framework for an evaluation system of the elderly care station. An SQ evaluation index system for the elderly care station is designed according to the service and construction standards. A fuzzy hierarchical entropy method is then used to identify the weights such that the calculation steps are reduced and the decision‐making process is more objective. Based on that, a fuzzy comprehensive evaluation model is established. For integrating the SQ and service quantity provided by stations, a quality‐quantity quadrant model is proposed, which is used to discover the stations or operators with adequate SQ and service quantity to subsidy and the inadequate to give priority attention and rectification by quantifying and visualizing the service situation of all stations and their operators. Meanwhile, we conduct an empirical analysis by using the data of one station.
Visible‐Light Photoredox‐Catalyzed Ring‐Opening Carboxylation of Cyclic Oxime Esters with CO2
Authors: Jiang Yuan‐Xu , Chen Liang , Ran Chuan‐Kun , Song Lei , Zhang Wei , Liao Li‐Li , Yu Da‐Gang
Published: October 2020

The carboxylation of cyclic oxime esters with carbon dioxide via visible‐light photoredox catalysis is demonstrated for the first time. A variety of cyclic oxime esters undergo ring‐opening C−C bond cleavage and carboxylation to give cyanoalkyl‐containing carboxylic acids in moderate to good yields. Moreover, this methodology features mild reaction conditions (room temperature, 1 atm), wide substrate scope, good functional group tolerance as well as facile derivations of products. Mechanistic studies indicate that the benzylic radicals and anions might be the key intermediates.
FNA diagnostics of secondary malignancies in the salivary gland: Bi‐institutional experience of 36 cases
Authors: Horáková Markéta , Porre Sinikka , Tommola Satu , Baněčková Martina , Skálová Alena , Kholová Ivana
Published: October 2020

Objective

Fine‐needle aspiration (FNA) is a key diagnostic method in the evaluation of salivary gland lesions. Secondary tumors of salivary glands represent only 5% of all malignancies of major salivary glands. The goal of our study was to examine the cytological and clinical features of secondary tumors sampled by FNA.

Materials and Methods

A series of 36 secondary tumors from the pathology departments of two university hospitals are presented. Clinical referrals to FNA, cytological features, immunohistochemical results, and histopathological diagnoses were reviewed in all cases.

Results

The study population consisted of 36 cases (19 males and 17 females) with mean age 70.9 ± 13.0 years (range 41‐96 years). The most common site of the metastasis was parotid gland (n = 26). The primary malignancy was known in 17 cases at the time of FNA diagnosis. The most common primary site was skin of head and neck area (11 cases) followed by lungs (n = 5) and tonsils (n = 5), kidney (n = 2) and breast (n = 2) and thyroid gland, gastrointestinal tract and soft tissue, 1 case of each. In 8 cases, the primary site remained unknown. The diagnostic or confirmatory immunocytochemistry was performed on cell blocks in 21 cases.

Conclusions

FNA is a reliable technique in the diagnosis of salivary gland secondary malignancies. The knowledge of the personal history of malignancy is essential for the successful immunocytochemical targeted diagnosis without any delay.
Accuracy of the International Academy of Cytology Yokohama system of breast cytology reporting for fine needle aspiration biopsy of the breast in a dedicated breast care setting
Authors: Agarwal Akansha , Singh Divya , Mehan Anoushika , Paul Pranoy , Puri Neeti , Gupta Priyanka , Syed Anjum , Rao Shalinee , Chowdhury Nilotpal , Ravi Bina
Published: October 2020

Background

The International Academy of Cytology (IAC) Yokohama system is a recently proposed system for reporting breast cytology by fine needle aspiration biopsies (FNAB). Multiple studies are needed to confirm the risk of malignancy (ROM) of the various reporting categories of this system. The present article studies the accuracy of the IAC Yokohama system in our center.

Methods

Over a period of 1 year (September 2018‐August 2019), all cases of breast masses assessed by FNAB and histological correlation were studied retrospectively. Sensitivity, specificity, negative predictive value (NPV) and positive predictive value (PPV) and overall accuracy of the IAC Yokohama system for diagnosing malignancy were assessed. The rates of malignancy (ROM) of each diagnostic category were also estimated.

Results

Three hundred and twenty‐one FNABs had cyto‐histological correlation. The percent sensitivity (with 95% Confidence Intervals) when the atypical, suspicious of malignancy and the malignant categories were regarded as positive for malignancy were 98.2% [95.5%, 99.5%], 96.0% [92.5%, 98.2%], and 86.7% [81.5%, 90.8%] respectively. The percent specificity (with 95% Confidence intervals) for the same categories in the same order were 59.5% [47.4%, 70.7%], 91.9% [83.2%, 97.0%], and 100% [95.1%, 100%] respectively. The area under curve (AUC) for diagnosing malignancy was 0.981[0.963, 0.993]. The ROM for the benign, atypical, suspicious of malignancy and malignant category were 8.3% [2.3%, 20.0%], 17.2% [5.8%, 35.8%], 77.8% [57.7%, 91.4%], and 100% [98.1%, 100%] respectively.

Conclusion

The IAC Yokohama system is suitable for accurately reporting breast lesions on FNAB.
Quality of life of patients with keloid at the Regional Dermatology Training Centre, Northern Tanzania
Authors: Hassan Hafidh S. , Masenga Elisante J.
Published: October 2020

Background

Keloids are reported to be amongst the common conditions seen in the pigmented skin of African origin with an estimate of about 15 times more compared with other races. They seldom resolve spontaneously, have a poor response to treatment and pose enormous impact on quality of life (QoL) in affected individuals. Aesthetic discomfort, depression, low self‐esteem and some degree of isolation increase the burden of the disease.

Methods

This hospital‐based cross‐sectional study was conducted at the Regional Dermatology Training Centre in Northern Tanzania. A total of 117 patients with keloid older than 18 years attended the skin clinic from October 2017 to April 2018. Data were collected using disease‐specific structured questionnaire and all were assessed using the Dermatology Life Quality Index (DLQI) Questionnaire.

Results

The mean DLQI for this population was 8.3 ± 7.4 reflecting a moderate impairment. The QoL seemed to be influenced by the number of keloids, duration of disease and the presence of symptoms. It was mainly seen in young adults with a median age of 29 years (range: 18–88 years). There was no significant sex predilection. Trauma as an inciting event was reported in 42%.

Conclusion

Keloid patients with pigmented skin of African descent in Northern Tanzania have a moderate impairment in the QoL.
Detecting changes in statistical indicators of resilience prior to algal blooms in shallow eutrophic lakes
Authors: Ortiz David , Palmer Jason , Wilkinson Grace
Published: October 2020

Algal blooms in lakes and reservoirs can be considered regime shifts from a clear‐water to algae‐dominated state that often occurs abruptly. Under experimental conditions, these regime shifts have been predicted from rises in variance and autocorrelation (generic resilience indicators) of state variables monitored at a high frequency. The goal of this study was to evaluate the behavior of resilience indicators prior to a critical transition in lakes that naturally experience algal blooms. Ambient lake conditions provide several potential hurdles that could inhibit the detection of meaningful changes in resilience indicators prior to a critical transition such as stochastic nutrient loading, spatial complexity, and decreased resilience due to higher baseline nutrient concentrations. We compiled five lake‐years of high‐frequency monitoring of chlorophyll a, phycocyanin, dissolved oxygen, and pH from four hypereutrophic lakes. Despite the factors that might hinder detecting statistical indicators of changing resilience in hypereutrophic ecosystems, we found that a rise in resilience indicators did occur prior to a critical transition in three out of four possible lake‐years, with rise beginning between 5 and 33 d prior. In one lake‐year, a critical transition occurred soon after the monitoring began, preventing detection of rising variance or autocorrelation signals which are calculated using a 21‐d rolling window. These results add to the growing body of evidence that rises in resilience indicators can be detected in ecosystems prior to a regime shift if monitoring programs are properly designed to capture the dynamics; however, continued research is needed to better understand the conditions under which resilience indicators may be useful as an early warning detection tool for lake management.
Can oceanic prey effects on growth and time to fledging mediate terrestrial predator limitation of an at‐risk seabird?
Authors: Knudson Timothy W. , Lovvorn James R. , Lawonn M. James , Corcoran Robin M. , Roby Daniel D. , Piatt John F. , Pyle William H.
Published: October 2020

Most seabird species nest colonially on cliffs or islands with limited terrestrial predation, so that oceanic effects on the quality or quantity of prey fed to chicks more often determine nest success. However, when predator access increases, impacts can be dramatic, especially when exposure to predators is extended due to slow growth from inadequate food. Kittlitz’s Murrelet (Brachyramphus brevirostris), a rare seabird having experienced serious declines, nests solitarily on the ground in barren, often alpine areas where exposure to predators is generally low. Nestling growth rates are exceptionally high and nestling periods very short relative to other Alcidae. This strategy reduces duration of exposure to predators, but demands adequate deliveries of high‐energy prey. In an area where foxes can access nests, we investigated whether varying energy content of prey fed to chicks could alter growth rates and resulting duration of predator exposure, and whether prolonged exposure appreciably reduced nest success. From 2009 to 2016, we monitored 139 nests; 49% were depredated (almost all by foxes) and 25% fledged. Prey fed to nestlings were 80% Pacific sand lance (Ammodytes personatus) and 19% capelin (Mallotus villosus), with capelin having 2.3× higher energy content per fish. In a year of slow chick growth, increased sand lance energy density of 31% (4.29–5.64 kJ/g, within published values), or increased proportion of capelin in the diet from 5.6% to 27.2%, would have allowed maximum chick growth. Maximum growth rates were attainable by delivering only 1.9 capelin/d versus 5.5 sand lance/d. Slow growth increased time to fledging by up to 5 d, decreasing survival by 7.7% (0.142–0.131). Breeding propensity of Kittlitz’s Murrelet averages only 20%, so even small changes in nest success could affect populations. Although nest success was limited mainly by predation, oceanic effects on prey quantity and quality had overriding impacts in one year (2015 heat wave), and small but substantive effects in other years by mediating exposure to predation. Climate warming that decreases availability of high‐energy forage fish, or increases expansion of predators into nesting habitats, may disproportionately affect this sensitive species and others with predator‐accessible nests and demands for energy‐rich prey.
CE‐MS for metabolomics: Developments and applications in the period 2018–2020
Authors: Zhang Wei , Ramautar Rawi
Published: October 2020

Capillary electrophoresis‐mass spectrometry (CE‐MS) is now a mature analytical technique in metabolomics, notably for the efficient profiling of polar and charged metabolites. Over the past few years, (further) progress has been made in the design of improved interfacing techniques for coupling CE to MS; also, in the development of CE‐MS approaches for profiling metabolites in volume‐restricted samples, and in strategies that further enhance the metabolic coverage. In this article, which is a follow‐up of a previous review article covering the years 2016–2018 (Electrophoresis 2019, 40, 165–179), the main (technological) developments in CE‐MS methods and strategies for metabolomics are discussed covering the literature from July 2018 to June 2020. Representative examples highlight the utility of CE‐MS in the fields of biomedical, clinical, microbial, plant and food metabolomics. A complete overview of recent CE‐MS‐based metabolomics studies is given in a table, which provides information on sample type and pretreatment, capillary coatings, and MS detection mode. Finally, some general conclusions and perspectives are given.
An integrated performance‐based design framework for building‐foundation systems
Authors: Millen Maxim D. L. , Pampanin Stefano , Cubrinovski Misko
Published: October 2020

This paper presents a framework for the inclusion of transient and residual foundation deformations within performance‐based seismic design of buildings. A refinement of existing displacement‐based design procedures is proposed that reduces iteration when obtaining the expected peak foundation rotation. Empirical equations are developed based on numerical time‐history analyses that provide an estimation of foundation residual deformations based on the foundation peak rotation. Additional complexities due to deformation within the foundation are discussed regarding how they influence the design and building performance. The design framework is complemented by a simplified analytical design procedure (i.e., hand calculations) to design building‐foundation systems. A design example is given for a six‐storey concrete wall building, which is analyzed by time‐history analysis to demonstrate the application and accuracy of the design procedure.
Per- and Polyfluoroalkyl Substance Toxicity and Human Health Review: Current State of Knowledge and Strategies for Informing Future Research
Authors: Fenton Suzanne E. , Ducatman Alan , Boobis Alan , DeWitt Jamie C. , Lau Christopher , Ng Carla , Smith James S. , Roberts Stephen M.
Published: October 2020

Reports of environmental and human health impacts of per- and polyfluoroalkyl substances (PFAS) have greatly increased in the peer-reviewed literature. The goals of the present review are to assess the state of the science regarding toxicological effects of PFAS and to develop strategies for advancing knowledge on the health effects of this large family of chemicals. Currently, much of the toxicity data available for PFAS are for a handful of chemicals, primarily legacy PFAS such as perfluorooctanoic acid and perfluorooctane sulfonate. Epidemiological studies have revealed associations between exposure to specific PFAS and a variety of health effects, including altered immune and thyroid function, liver disease, lipid and insulin dysregulation, kidney disease, adverse reproductive and developmental outcomes, and cancer. Concordance with experimental animal data exists for many of these effects. However, information on modes of action and adverse outcome pathways must be expanded, and profound differences in PFAS toxicokinetic properties must be considered in understanding differences in responses between the sexes and among species and life stages. With many health effects noted for a relatively few example compounds and hundreds of other PFAS in commerce lacking toxicity data, more contemporary and high-throughput approaches such as read-across, molecular dynamics, and protein modeling are proposed to accelerate the development of toxicity information on emerging and legacy PFAS, individually and as mixtures. In addition, an appropriate degree of precaution, given what is already known from the PFAS examples noted, may be needed to protect human health. Environ Toxicol Chem 2021;40:606–630. © 2020 SETAC

Abstract

Many health effects have been reported in association with or due to per- and polyfluoroalkyl substance (PFAS) exposures in humans and toxicologic models. Species concordance of effects is evident for a handful of legacy PFAS. With hundreds of PFAS in commerce that lack exposure and health effects data, contemporary and novel methods must be implemented to inform exposed communities, risk assessors, and concerned citizens and prioritize those most likely to affect human health.