bluuebunny/crossref_metadata_2025 huggingface dataset:
A thermally reversible healing EPDM based elastomer with higher tensile properties and damping properties
Authors: Xiong Chengtian , Li Xiaoqing , He Hezhi , Xue Bin , Wang Yi , Li Jiqian , Zhu Zhiwen
Published: September 2020

Due to the disadvantages of lower tensile strength and fracture toughness, the widely application of Ethylene‐propylene‐diene‐monomer rubber (EPDM) has been limited. In this study, a thermally reversible healing EPDM based elastomer with H‐bonding and Zn‐based‐bonding dynamic cross‐link network was prepared. The influence of mole ratio of ATA/MAH on tensile strength and fracture energy of mEPDM0‐xATA was investigated. The results showed that increasing the content of ATA brings about a gradual improvement in tensile strength of the mEPDM0‐xATA. Especially when the mole ratio of ATA/MAH is 1, the fracture energy of mEPDM0‐ATA is dramatically enhanced to 33.9 MJ/m3, which is best among the ratios studied in our research. After curing, the effect of ZnCl2 content on tensile strength and fracture energy of mEPDM‐ATA‐nZn was also studied. Meanwhile, the uniaxial cyclic loading‐unloading tensile test was used to study the viscous damping properties of mEPDM‐ATA‐0.4Zn, which showed reversible repair properties after heat treatment. The results of dynamic rheological measurement showed that the damping properties were improved.
Synthesis and characteristics of pectiniform polyurethane‐modified polycarboxylate and its effects on behavior of cement paste
Authors: Xiang Shuncheng , Gao Yingli
Published: September 2020

In this research, two kinds of polycarboxylate (M‐PCE and O‐PCE) with the same degree of polymerization in side chains but different main chains were synthesized via a radical polymerization reaction at room temperature. Along with two commercial polycarboxylates (C‐PCE‐1 and C‐PCE‐2), their properties on adsorption, hydration, zeta potential, liquid surface tension, and flowability of cement pastes were investigated. The results showed that the adsorption of M‐PCE on the surface of cement particles increased 14.1% and the adsorption rate increased 24% compared with C‐PCEs. Furthermore, three polycarboxylates (O‐PCE, C‐PCE‐1, and C‐PCE‐2) exhibited a delayed effect on the hydration of cement due to the shielding effect of their chain alkyl groups, meanwhile the hydration of the cementitious materials by the M‐PCE was not delayed but promoted because of its incomplete hydrolysis of the siloxane. As a result of the higher adsorption amount, M‐PCE with siloxane groups exhibited favorable effects in terms of zeta potential, liquid surface tension, and flowability of cement pastes.
Synergistic flame retardant effect of piperazine salt and ammonium polyphosphate as intumescent flame retardant system for polypropylene
Authors: Pan Yingtong , Luo Zhonglin , Wang Biaobing
Published: September 2020

Amino trimethylene phosphonic acid piperazine (ATPIP)salt, as a novel charring agent, is prepared via a simple ionic reaction in distilled water using amino trimethylene phosphate (ATMP) and piperazine as raw materials. The synergistic flame retardant effect of ATPIP and ammonium polyphosphate (APP) as an intumescent flame retardant (IFR) is investigated by various characterization and testing methods. The results show that the polypropylene (PP)/modified APP with piperazine (MAPP)/ATPIP ternary blend passes UL‐94 V‐0 rating and achieve a limiting oxygen index (LOI) of 30% at a loading level of 25 wt% IFR (MAPP:ATPIP = 3:1). Meanwhile, the total smoke production (TSP) value of IFR‐PP samples is 3.3 m2, which decreases by 93.2% compared with that of pure PP, exhibiting excellent smoke suppression performance. Besides, the analysis of gaseous pyrolysis products and char residue indicates that the IFR‐PP samples show a synergistic flame‐retardant mechanism including the gas phase and the condensed phase.
The effect of graphene flake size on the properties of graphene‐based polymer composite films
Authors: Tarhini Ali , Tehrani‐Bagha Ali , Kazan Michel , Grady Brian
Published: September 2020

In this work, the role of graphene flake size on the properties of poly(vinylidene fluoride‐co‐hexafluoropropylene) (PVDF‐HFP) composites was studied. Graphene flakes were added to PVDF‐HFP using a solution mixing and molding process. By increasing graphene particle size and its concentration in the composites, higher electrical conductivity, in‐plane thermal conductivity, and elastic modulus were achieved. Maximum tensile strength was obtained for the composites with average graphene flake size of 2, 5, and 7 μm at graphene concentrations of 10 wt%, 5 wt%, and 20 wt%, respectively. Thick flexible composite films (0.2–0.4 mm) with ultra‐high in‐plane electrical conductivity (~4500 S/m), in‐plane thermal conductivity (~26 W/m/K), and tensile strength (~50 MPa) were obtained for the samples containing the graphene flakes with a larger average particle size of 7 μm. To our knowledge, the first two values are larger than any other values reported in the literature for PVDF‐based composites.
Attaining low percolation threshold in conductive polypropylene/nitrile rubber thermoplastic vulcanizates using carbon nanotube
Authors: de Alencar Padua Gabino Alessandra , Soares Bluma Guenther , Silva Adriana Anjos
Published: September 2020

Electrically conductive thermoplastic vulcanizates (TPV) based on polypropylene (PP)/nitrile rubber (NBR) blends loaded with multiwalled carbon nanotube (CNT) were prepared by dynamic vulcanization. CNT was incorporated into the system using two different mixing sequences: (i) one‐step method, by adding CNT after the PP and NBR and (ii) two‐steps method involving a previous PP/CNT master batch. Scanning electron microscopy and transmission electron microscopy were used to analyze the morphology of the nanocomposites. Dynamic‐mechanical analysis and rheological properties were also used for characterizing the TPV and TPE samples. Both mixing strategies favored the location of the CNT inside the PP phase. The one‐step approach resulted in a percolation threshold as low as 0.19 vol% with conductivity value of 0.04 S m−1 for the system loaded with only 0.50 vol% of CNT. The electromagnetic interference shielding effectiveness and microwave absorbing properties were evaluated in the X‐band frequency range. The TPV samples prepared by both methods displayed an overall electromagnetic attenuation of around 70%.
Fabrication of hybrid proton‐exchange membranes using a brandnew high temperature ionic liquid as charge transporting and clay modifier
Authors: Rubio Arias Jose Jonathan , Bento Sabrina dos Santos , Vieira Marques Maria de Fátima , Gomes Ailton de Souza
Published: September 2020

The search for more compatibility between ionic liquids (ILs) and polymer matrices in proton‐exchange membrane fuel cells (PEMFCs) is one of the ways in which IL leaking from proton‐exchange membranes could be minimized. In this work, it is presented the synthesis of an aromatic high temperature ionic liquid (HTIL), which, incorporated into an aromatic matrix such as sulfonated polyether ether ketone (sPEEK), is expected to diminish the IL leaking that normally affects PEMFC. Phenylethylammonium trifluoromethane sulfonate (PhetaTfO) was successfully synthesized and characterized. Its melting point of 88°C makes it to classify as a HTIL and it was employed as modifier of natural Montmorillonite, forming the phenylethylammonium intercalated montmorillonite (MmtPheta) and thus, ternary membranes containing PhetaTfO, MmtPheta, and sPEEK were prepared and characterized. Immersion tests demonstrated a higher compatibility of PhetaTfO with matrix when compared to the reference DemaTfO, which was reflected in up to 30% lower IL loss by the synthesized IL than the DemaTfO; X‐rays diffraction (XRD) patterns demonstrated that the modified clay was properly dispersed inside the membranes, while dynamic mechanical analyses (DMA) results indicated a strong plasticizer effect along the increase of PhetaTfO content inside the membrane, while at the same time, the conductivity increased in an exponential manner, which permitted to identify an empiric exponential equation to evaluate the effect of concentration on ionic conductivity. The maximum conductivity obtained at IL concentrations of around 38 wt% was 0.2 mS/cm. It could expect high ionic conductivities of 10 mS/cm when the concentration of this IL is 60%; nevertheless, in order to achieve that, crosslinking treatments should be done to give the membranes enough mechanical resistance.
Preparation of composite anion exchange membranes based on in‐situ copolymerization of N‐vinyl formamide and divinylbenzene in porous PTFE
Authors: Luo Wanjie , Wang Lulu , Feng Ruijiang , Zhao Chongfeng , Wang Jilin , Cai Tianzhou
Published: September 2020

A series of composite anion exchange membranes was synthesized via in‐situ copolymerization of various ratios N‐vinyl formamide (NVF) and divinylbenzene (DVB), supported by porous polytetrafluoroethylene (PTFE) polymer matrix, and followed by alkaline hydrolysis, and quaternization of the composite membranes with epoxypropyltrimethylammonium chloride (EPTMAC). FTIR and SEM analyses revealed that the composite membranes were successfully prepared. Moreover, the hydrophilic property of the composite membrane improved by introduction of the quaternized poly(NVF‐co‐DVB) copolymer. Water uptake, swelling ratio, and conductivity showed upward trends by increase of NVF amount. The copolymer with 95% of NVF showed the highest elongation at break (102%, room temperature) and conductivity (5.15 × 10−2 S/cm, 80°C). After immersion of the PNDB95%‐N membrane in 5 mol/L NaOH solution for 96 h at room temperature, the conductivity (60°C) of the membrane decreased to 3.99 × 10−2 S/cm. Moreover, the membrane registered weight loss under 4.5%, caused by degradation of the quaternary ammonium groups in NaOH solution. All in all, in 3 mol/L methanol solutions, the composite membranes showed permeability ranging from 7.6% to 19.7%, if compared to the Nafion®‐115 membrane, showing good alcohol resistance.
Surfactant‐free synthesis of poly (styrene‐co‐acrylamide) monodisperse nanoparticles using hybrid flow‐to‐batch chemistry
Authors: Antoniv Marta , Chang Sehoon , Al‐Jabri Nouf , Zhu S. Sherry
Published: September 2020

We have demonstrated a hybrid flow‐to‐batch process for synthesizing monodisperse poly(styrene‐co‐acrylamide) nanoparticles via a surfactant‐free emulsion radical polymerization. The flow‐to‐batch synthesized nanoparticles have a smaller average particle size, tighter particle size distribution, higher molecular weight, and lower molecular weight distribution compared to conventionally batch‐synthesized nanoparticles. Our results also indicate that the flow‐to‐batch synthesized nanoparticles have more hydrophilic acrylamide segments on the particle surface than the batch‐synthesized nanoparticles. These results demonstrate that a flow synthesis process can improve the quality of nanoparticles due to the efficient mixing and heat transfer in a flow reactor and simplify the scale up of nanoparticle synthesis in a conventional chemistry lab.
Preparation and characterization of modified castor oil via photo‐click chemistry forUV‐curable waterborne polyurethane with enhanced water resistance and low conductive percolation threshold
Authors: Dai Mengwei , Song Pan , Zhang Yong
Published: September 2020

A castor oil (CO) was modified via thiol‐ene click chemistry reaction between CO and 3‐mercaptopropyl trimethoxysilane, with the conversion of CC bonds of CO over 99% based on1HNMR spectra. The obtained modified castor oil (MCO) was used as a biobased polyol to prepare waterborne polyurethane (WPU) dispersions. The modification of CO exhibited a great effect on the properties of WPU dispersions and coatings, and an obvious change is the improvement of the water resistance of WPU coatings. WPU dispersions with MCO had good storage stability. A WPU coating with 7% MCO had high surface hydrophobicity, and its water absorption was as low as 3.2%. Conductive carbon black filled WPU coatings with MCO were cured by efficient UV radiation, and their conductive percolation threshold could decrease to 0.76%, which could be attributed to the well filler dispersion and strong filler‐polymer interaction. The WPU dispersions are ecofriendly, and can be used to produce biobased WPU coatings with a great application potential in antistatic coating fields.
Intraspecies variation in ectotympanic tube length and orientation among humans
Authors: Fricano Ellen , DeLeon Valerie B.
Published: September 2020

Ectotympanic bone morphology is commonly used as a large‐scale phylogenetic indicator across primates. Less well‐understood is the intraspecies variation in this characteristic and the dynamic ways in which it affects and is affected by overall basicranial shape. This study attempts to clarify relationships between the external ear canal and basicranial shape among humans in a sample of archaeological human crania. The ectotympanic length and orientation were hypothesized to correlate with the shape of the cranial base and particularly with shape variables associated with relative brachycephaly. Basicranial shape in 80 computed tomography (CT) scans of adult humans were quantified using landmark coordinate data, with particular emphasis on the cranial base and auditory structures. Scaled ectotympanic lengths were taken from interlandmark distances and then compared to shape variation of the whole basicranium as summarized by procrustes shape variables and principal components analysis (PCA). The length of the ectotympanic bone was correlated with total cranial base variation. Long ectotympanic bones were found to be associated with brachycephalic individuals and less flexed basicrania. Additionally, long ectotympanic bones were found to be more horizontally oriented, as opposed to inferiorly sloped. We suggest that as brachycephaly increases the distance between the otic capsule and the pinna, the ectotympanic bone lengthens in response.
Increased survival of the honey bee Apis mellifera infected with the microsporidian Nosema ceranae by effective gene silencing
Authors: Kim In‐Hui , Kim Dong‐Jun , Gwak Won‐Seok , Woo Soo‐Dong
Published: September 2020

This study examined the control of nosemosis caused by Nosema ceranae, one of the hard‐to‐control diseases of honey bees, using RNA interference (RNAi) technology. Double‐stranded RNA (dsRNA) for RNAi application targeted the mitosome‐related genes of N. ceranae. Among the various mitosome‐related genes, NCER_100882, NCER_101456, NCER_100157, and NCER_100686 exhibited relatively low homologies with the orthologs of Apis mellifera. Four gene‐specific dsRNAs were prepared against the target genes and applied to the infected A. mellifera to analyze Nosema proliferation and honey bee survival. Two dsRNAs specifics to NCER_101456 and NCER_100157 showed high inhibitory effects on spore production by exhibiting only 62% and 67%, respectively, compared with the control. In addition, these dsRNA treatments significantly rescued the honey bees from the fatal nosemosis. It was confirmed that the inhibition of Nosema spore proliferation and the increase in the survival rate of honey bees were resulted from a decrease in the expression level of each target gene by dsRNA treatment. However, dsRNA mixture treatment was no more effective than single treatments in the rescue from the nosemosis. It is expected that the four newly identified mitosome‐related target genes in this study can be effectively used for nosemosis control using RNAi technology.
Calcium Pyrophosphate Dihydrate Crystal Deposition in Gouty Tophi
Authors: Ea Hang‐Korng , Gauffenic Alan , Nguyen Quang Dinh , Pham Nhu G. , Olivier Océane , Frochot Vincent , Bazin Dominique , Le Nghia H. , Marty Caroline , Ostertag Agnès , Cohen‐Solal Martine , Laredo Jean‐Denis , Richette Pascal , Bardin Thomas
Published: September 2020

Objective

The coexistence of calcium pyrophosphate dihydrate (CPPD) and monosodium urate monohydrate crystals in gouty tophi has rarely been reported. We undertook this study to investigate CPPD crystal deposits in a series of surgically removed gouty tophi and to identify factors associated with these deposits.

Methods

Twenty‐five tophi from 22 gout patients were analyzed using polarized light microscopy, field emission scanning electron microscopy (FESEM), and μ Fourier transform infrared (μFTIR) spectroscopy.

Results

Tophi consisted of multiple lobules separated by fibrous septa and surrounded by a foreign‐body giant cell reaction. CPPD crystal aggregates were identified in 9 of 25 tophi from 6 patients. CPPD crystals were dispersed or highly compacted, localized at the edge or inside the tophus lobules, with some lobules completely filled with crystals. Both monoclinic and triclinic CPPD crystal phases were identified using FESEM and μFTIR. Compared to patients without CPPD, those with CPPD‐containing tophi were older (mean 60.5 years versus 47.2 years; P = 0.009), and had longer‐term gout duration (mean 17.0 years versus mean 9.0 years; P < 0.05) and tophi duration (mean 10.0 years versus mean 4.6 years; P < 0.01). None of the patients had radiographic chondrocalcinosis of the knee or wrist.

Conclusion

CPPD crystal formation seems to be a late and frequent event of tophus maturation, occurring more frequently with aging, and could contribute to the speed of tophus dissolution and the apparent persistence of tophus sometimes observed even after effective, long‐lasting urate‐lowering therapy.
Role of Vacancies in Photocatalysis: A Review of Recent Progress
Authors: Ai Minhua , Zhang Jing‐Wen , Wu Yi‐Wei , Pan Lun , Shi Chengxiang , Zou Ji‐Jun
Published: September 2020

Photocatalysis via direct solar‐to‐chemical energy conversion is an intriguing approach for alleviating the pressure of high energy consumption caused by social development. However, photocatalytic efficiency is greatly restricted by unsatisfactory light‐harvesting capacity, high carrier recombination rates, and sluggish reaction kinetics. Indeed, vacancy engineering is an attractive strategy to regulate photocatalytic reaction performance to maximize the utilization and storage of solar energy. In this review, we summarize recent progress about the important roles of vacancy defects on solar‐driven photocatalytic applications. The current advanced characterization techniques, especially for in situ/operando techniques, are first presented for elucidating the structure‐performance relationships of defective semiconductors in photocatalysis. Subsequently, the crucial roles of vacancies in enhancing photocatalytic performance are highlighted from three important processes: light absorption, carrier separation and migration, and surface reaction. Finally, based on the above understanding, perspectives and opportunities about defective materials are considered for various photocatalytic applications.
Effects of stability functions in a dynamic model convective boundary layer simulation
Authors: Bopape Mary‐Jane M. , Plant Robert S. , Coceal Omduth , Efstathiou Georgios A. , Valdivieso Maria
Published: September 2020

Dynamic subgrid models are increasingly being used in simulations of the atmospheric boundary layer. We have implemented several variant forms of dynamic models in the UK Met Office Large Eddy Model (MetLEM), including a state‐of‐the‐art Lagrangian‐Averaged‐Scale‐Dependent (LASD) model. The implementation includes optional use of stability functions in the specification of the eddy viscosity and diffusivity, as well as optional use within the dynamic calculation of the Smagorinsky parameter. This paper reports on the behaviour of the LASD model with different choices for the inclusion and treatment of stability functions in convective boundary layer simulations at different resolutions. Results are compared against a high‐resolution Large‐Eddy simulation (LES) and against simulations employing the Smagorinsky–Lilly subgrid model. We conclude that the use of stability functions improves the behaviour of the LASD model in the grey zone regime. Moreover, a careful treatment of the stability functions in the calculation of the dynamic parameters, while attractive theoretically, is found to be unnecessary in practical terms.
Predictability of European Winters 2017/2018 and 2018/2019: Contrasting influences from the Tropics and stratosphere
Authors: Knight Jeff , Scaife Adam , Bett Philip E. , Collier Tamara , Dunstone Nick , Gordon Margaret , Hardiman Steven , Hermanson Leon , Ineson Sarah , Kay Gillian , McLean Peter , Pilling Charles , Smith Doug , Stringer Nicky , Thornton Hazel , Walker Brent
Published: September 2020

The European winters of 2017–18 and 2018–19 were not climatically extreme, but both winters had a major sudden stratospheric warming (SSW). In February 2018, an SSW led to an intense cold outbreak across Europe and further spells of cold weather in March. The SSW of January 2019, although well predicted and expected to increase the chance of a cold end to winter, apparently produced little impact. In this study, we examine the performance of the Met Office seasonal prediction system in these winters, and the influences that led to these outcomes. To achieve this latter objective, sets of numerical experiments are performed in which the tropical troposphere and the extratropical stratosphere are relaxed towards their observed state, allowing the influence of each on the North Atlantic‐European atmospheric circulation to be identified. Using these experiments, we show that the SSWs had similar impacts in each case, creating a signal of easterly surface wind anomalies in the weeks following the event. In contrast, tropical influences were opposite in the two winters, acting to strengthen the easterly signal at the end of February 2018 and opposing it in January 2019. The different apparent responses to the two events therefore came about largely through tropical tropospheric variability. Furthermore, we highlight the importance of a very strong cycle of the Madden‐Julian Oscillation (MJO) in late January and early February 2018 as an important driver for the February 2018 SSW. MJO teleconnections appear to have been critical in creating the large mid‐latitude wave 2 amplitude that has been identified as the immediate cause of this event.
Bayesian hierarchical spatial regression models for spatial data in the presence of missing covariates with applications
Authors: Ma Zhihua , Hu Guanyu , Chen Ming‐Hui
Published: September 2020

In many applications, survey data are collected from different survey centers in different regions. It happens that in some circumstances, response variables are completely observed while the covariates have missing values. In this article, we propose a joint spatial regression model for the response variable and missing covariates via a sequence of one‐dimensional conditional spatial regression models. We further construct a joint spatial model for missing covariate data mechanisms. The properties of the proposed models are examined and a Markov chain Monte Carlo sampling algorithm is used to sample from the posterior distribution. In addition, the Bayesian model comparison criteria, the modified deviance information criterion and the modified logarithm of the pseudo‐marginal likelihood, are developed to assess the fit of spatial regression models for spatial data. Extensive simulation studies are carried out to examine empirical performance of the proposed methods. We further apply the proposed methodology to analyze a real dataset from a Chinese Health and Nutrition Survey conducted in 2011.
Smart contract for electricity transactions and charge settlements using blockchain
Authors: Lu Jing , Wu Shihong , Cheng Hanlei , Song Bin , Xiang Zhiyu
Published: September 2020

In this article, aimed at the future “let go” electricity market, smart contracts for grid enterprises doing electricity transactions and charge settlements based on blockchain technology, as well as the trading model using the smart contracts, are proposed. Then the key technological difficulties are analyzed, and the solutions are given. The main goal of our research is to help developing the infrastructure for electricity market members, and match their bilateral trading. By running a smart contract instance in a peer‐to‐peer network composed by 4000 nodes, experiments show that the success rate is 99.38% and the average time consumption for each transaction is 16 seconds. If our method is applied, we can reduce the trust cost of the electric electricity market, and improve the efficiency of the electricity transaction and charge settlement.
Subgroups of Temperament Associated with Social–Emotional Difficulties in Infants with Early Signs of Autism
Authors: Chetcuti Lacey , Uljarević Mirko , Varcin Kandice J. , Boutrus Maryam , Wan Ming Wai , Green Jonathan , Iacono Teresa , Dissanayake Cheryl , Whitehouse Andrew J. O. , Hudry Kristelle ,   the AICES Team
Published: September 2020

Links between temperament and social–emotional difficulties are well‐established in normative child development but remain poorly characterized in autism. We sought to characterize distinct temperament subgroups and their associations with concurrent internalizing and externalizing symptoms in a sample of 103 infants (Mage = 12.39 months, SD = 1.97; 68% male) showing early signs of autism. Latent profile analysis was used to identify subgroups of infants with distinct temperament trait configurations on the Infant Behavior Questionnaire‐Revised. Derived subgroups were then compared in terms of internalizing and externalizing symptoms on the Infant–Toddler Social and Emotional Assessment. Three distinct temperament subgroups were identified: (a) inhibited/low positive (n = 22), characterized by low Smiling and Laughter, low High‐Intensity Pleasure, low Vocal Reactivity, and low Approach; (b) active/negative reactive (n = 23), characterized by high Activity Level, high Distress to Limitations, high Sadness, high Fear, and low Falling Reactivity; and (c) well‐regulated (n = 51), characterized by high Cuddliness, high Soothability, and high Low‐Intensity Pleasure. There were no differences in infant sex ratio, mean age or developmental/cognitive ability. Inhibited/low‐positive infants had significantly more behavioral autism signs than active/negative reactive and well‐regulated infants, who did not differ. Inhibited/low‐positive and active/negative reactive infants had higher internalizing symptoms, relative to well‐regulated infants, and active/negative reactive infants also had higher externalizing symptoms. These findings align closely with those garnered in the context of normative child development, and point to child temperament as a putative target for internalizing and externalizing interventions.

Lay Summary

This study explored whether infants with early signs of autism could be grouped according to temperament characteristics (i.e., emotional, behavioral, and attentional traits). Three subgroups were identified that differed with respect to emotional and behavioral difficulties. Specifically, “inhibited/low‐positive” infants had high emotional difficulties, “active/negative reactive” infants had high emotional and behavioral difficulties, while “well‐regulated” infants had the lowest difficulties.
Reward Devaluation in Autistic Children and Adolescents with Complex Needs: A Feasibility Study
Authors: Lambrechts Anna , Cook Jennifer , Ludvig Elliot A. , Alonso Eduardo , Anns Sophie , Taylor Maddison , Gaigg Sebastian B.
Published: September 2020

Rewards act as a motivator for positive behavior and learning. Although compounding evidence indicates that reward processing operates differently in autistic individuals who do not have co‐occurring learning disabilities, little is known about individuals who have such difficulties or other complex needs. This study aimed first to assess the feasibility of using an adapted reward devaluation paradigm to examine basic reward processes in this underrepresented population, and second to investigate whether autistic children and adolescents with complex needs would show dynamic behavioral changes in response to changes in the motivational value of a reward. Twenty‐seven autistic children and adolescents with complex needs and 20 typically developing 5‐year‐old children took part in the study. Participants were presented with two visual cues on a touchscreen laptop, which triggered the delivery of a video, music, or physical reward. One of the rewards was then presented in abundance to decrease its motivational value. Participants showed decreased interest in the video and music rewards after devaluation. The experimental setup was found to be suitable to test individuals with complex needs, although recommendations are made for the use of physical rewards. The results suggest that autistic participants with complex needs demonstrate goal‐directed behavior and that it is feasible to develop experimental paradigms that can shed important light on learning processes that are fundamental to many education and intervention strategies for this population. Autism Res 2020, 13: 1915‐1928. © 2020 The Authors. Autism Research published by International Society for Autism Research and Wiley Periodicals LLC.

Lay Summary

We adapted an experimental task to conduct research with autistic children and adolescents with complex needs, who remain grossly underrepresented in autism research. We found that once a reward was presented in great quantity, participants were less motivated to obtain it, showing that they adapted their behavior to changes in the value of that reward. This is an important finding to help promote learning and design better interventions for this population.
5 ways to increase your board's diversity
Authors: Dodds Amy
Published: September 2020

While the rallying cry to increase board diversity has sounded for years, the push for nonprofits to expand the number of people from underrepresented groups on their boards has gained more traction in the wake of nationwide protests calling for racial justice and equality. Below are five ways for boards to actively increase their diversity to help them make better decisions, provide and demonstrate equity, prevent unconscious blind spots and establish more connections to the community and its needs.
Recognising and responding to radicalisation at the ‘frontline’: Assessing the capability of school teachers to recognise and respond to radicalisation
Authors: Parker David , Lindekilde Lasse , Gøtzsche‐Astrup Oluf
Published: September 2020

Governments across the west have put teachers at the forefront of efforts to tackle radicalisation of young people based on their proximity to potentially vulnerable students. This has proven controversial, as critics claim that this securitises teachers’ work and that they cannot be expected to accurately identify and respond to extremism. Despite investment in P/CVE teacher training, research to assess teachers’ competence to identify signs of radicalisation and to respond in an appropriate manner is scarce. This article presents findings from a survey experiment with 2,173 teachers in Great Britain and Denmark. It shows that British and Danish teachers largely recognise radicalisation cues and respond to student radicalisation in similar ways. However, our data shows that British teachers are more likely than Danish teachers to react formally (e.g. report to authorities), and that British teachers feel more confident in reacting to signs of radicalisation. The results enhance our understanding of the effects of radicalisation prevention in schools. Furthermore, they challenge arguments within the extant literature by suggesting that what leads to concerns of radicalisation is not entirely subjective or completely context dependent.
Neue Erkenntnisse zur Qualitätssicherung von PP‐Faserbetonen am Beispiel des Straßentunnels Kriegsstraße
Authors: Shepherd David Alós , Helbig Ingo , Kühn Roman , Dehn Frank
Published: September 2020

Der 1,5 km lange Straßentunnel Kriegsstraße in Karlsruhe wird in offener Bauweise, mit Tunnelwänden und ‐decken aus PP‐Faserbeton, hergestellt. Entgegen der ZTV‐ING, Teil 5, werden 1,5 kg PP‐Fasern pro m3 Beton anstatt 2,0 kg/m3 dosiert. Die Minderdosierung an PP‐Fasern, zusammen mit einem ausführlichen Qualitätssicherungskonzept für den Beton, führte zu einer erhöhten Betonbauqualität, wie im Rahmen der Erst‐, Bauteil‐ und Identitätsprüfung nachgewiesen wurde. Durch die Reduktion der PP‐Fasermenge ist eine robustere, weniger temperaturempfindliche Betonmischung zielsicher herstellbar. Die PP‐Faserdosierung ist aufgrund des Einflusses auf die Frischbetoneigenschaften als zentraler Qualitätssicherungsparameter einzustufen. Die Wahl einer händischen oder automatischen Dosierung hat erheblichen Einfluss auf die Dosierungsgenauigkeit. Bei entsprechendem Erfahrungsnachweis im Umgang mit PP‐Faserbeton könnte ggf. das Nachweisverfahren zur Reduktion des PP‐Fasergehalts vereinfacht werden.
Biege‐ und Verbundverhalten von chemisch vorgespannten textilbewehrten Betonelementen
Authors: Zdanowicz Katarzyna , Schmidt Boso , Hansen Michael , Marx Steffen
Published: September 2020

Die chemische Vorspannung ist ein alternatives Verfahren zur Spannungseinleitung in Beton, das ohne mechanische Spannvorrichtungen auskommt. In diesem Beitrag werden die Ergebnisse von experimentellen Untersuchungen zum Trag‐ und Verformungsverhalten von dünnen textilbewehrten Quellbetonelementen vorgestellt. Hierzu wurden Verformungsmessungen zum freien und behinderten Quellen an Probekörpern unterschiedlicher Quellbetonmischungen sowie experimentelle Untersuchungen zum Biege‐ und Verbundverhalten von dünnen, mit Carbontextilgittern bewehrten Probekörpern durchgeführt. Die Versuchsergebnisse bestätigen, dass die Verwendung von Quellzusatzmitteln das Verhalten des Textilbetons beeinflusst. Die Beanspruchung bei Erstrissbildung sowie die Durchbiegung bei Erstrissbildung können mit zunehmendem Anteil von Quellzusatzmitteln erhöht werden. Zudem erreichen die Probekörper aus Quellbeton höhere maximale Verbundspannungen als entsprechende Probekörper ohne Quellzusatzmittel.
Variation in the ratio of curli and phosphoethanolamine cellulose associated with biofilm architecture and properties
Authors: Jeffries Jamie , Thongsomboon Wiriya , Visser Joshua Alan , Enriquez Kyle , Yager Deborah , Cegelski Lynette
Published: September 2020

Bacterial biofilms are communities of bacteria entangled in a self‐produced extracellular matrix (ECM). Escherichia coli direct the assembly of two insoluble biopolymers, curli amyloid fibers, and phosphoethanolamine (pEtN) cellulose, to build remarkable biofilm architectures. Intense curiosity surrounds how bacteria harness these amyloid‐polysaccharide composites to build biofilms, and how these biopolymers function to benefit bacterial communities. Defining ECM composition involving insoluble polymeric assemblies poses unique challenges to analysis and, thus, to comparing strains with quantitative ECM molecular correlates. In this work, we present results from a sum‐of‐the‐parts 13C solid‐state nuclear magnetic resonance (NMR) analysis to define the curli‐to‐pEtN cellulose ratio in the isolated ECM of the E. coli laboratory K12 strain, AR3110. We compare and contrast the compositional analysis and comprehensive biofilm phenotypes for AR3110 and a well‐studied clinical isolate, UTI89. The ECM isolated from AR3110 contains approximately twice the amount of pEtN cellulose relative to curli content as UTI89, revealing plasticity in matrix assembly principles among strains. The two parent strains and a panel of relevant gene mutants were investigated in three biofilm models, examining: (a) macrocolonies on agar, (b) pellicles at the liquid‐air interface, and (c) biomass accumulation on plastic. We describe the influence of curli, cellulose, and the pEtN modification on biofilm phenotypes with power in the direct comparison of these strains. The results suggest that curli more strongly influence adhesion, while pEtN cellulose drives cohesion. Their individual and combined influence depends on both the biofilm modality (agar, pellicle, or plastic‐associated) and the strain itself.
Optimization of 1,2,4‐butanetriol production from xylose in Saccharomyces cerevisiae by metabolic engineering of NADH/NADPH balance
Authors: Yukawa Takahiro , Bamba Takahiro , Guirimand Gregory , Matsuda Mami , Hasunuma Tomohisa , Kondo Akihiko
Published: September 2020

1,2,4‐Butanetriol (BT) is used as a precursor for the synthesis of various pharmaceuticals and the energetic plasticizer 1,2,4‐butanetriol trinitrate. In Saccharomyces cerevisiae, BT is biosynthesized from xylose via heterologous four enzymatic reactions catalyzed by xylose dehydrogenase, xylonate dehydratase, 2‐ketoacid decarboxylase, and alcohol dehydrogenase. We here aimed to improve the BT yield in S. cerevisiae by genetic engineering. First, the amount of the key intermediate 2‐keto‐3‐deoxy‐xylonate as described previously was successfully reduced in 41% by multiple integrations of Lactococcus lactis 2‐ketoacid decarboxylase gene kdcA into the yeast genome. Since the heterologous BT synthetic pathway is independent of yeast native metabolism, this manipulation has led to NADH/NADPH imbalance and deficiency during BT production. Overexpression of the NADH kinase POS5Δ17 lacking the mitochondrial targeting sequence to relieve NADH/NADPH imbalance resulted in the BT titer of 2.2 g/L (31% molar yield). Feeding low concentrations of glucose and xylose to support the supply of NADH resulted in BT titer of 6.6 g/L with (57% molar yield). Collectively, improving the NADH/NADPH ratio and supply from glucose are essential for the construction of a xylose pathway, such as the BT synthetic pathway, independent of native yeast metabolism.
Advances in encapsulin nanocompartment biology and engineering
Authors: Jones Jesse A. , Giessen Tobias W.
Published: September 2020

Compartmentalization is an essential feature of all cells. It allows cells to segregate and coordinate physiological functions in a controlled and ordered manner. Different mechanisms of compartmentalization exist, with the most relevant to prokaryotes being encapsulation via self‐assembling protein‐based compartments. One widespread example of such is that of encapsulins—cage‐like protein nanocompartments able to compartmentalize specific reactions, pathways, and processes in bacteria and archaea. While still relatively nascent bioengineering tools, encapsulins exhibit many promising characteristics, including a number of defined compartment sizes ranging from 24 to 42 nm, straightforward expression, the ability to self‐assemble via the Hong Kong 97‐like fold, marked physical robustness, and internal and external handles primed for rational genetic and molecular manipulation. Moreover, encapsulins allow for facile and specific encapsulation of native or heterologous cargo proteins via naturally or rationally fused targeting peptide sequences. Taken together, the attributes of encapsulins promise substantial customizability and broad usability. This review discusses recent advances in employing engineered encapsulins across various fields, from their use as bionanoreactors to targeted delivery systems and beyond. A special focus will be provided on the rational engineering of encapsulin systems and their potential promise as biomolecular research tools.
Minimally invasive techniques for transthoracic oesophagectomy for oesophageal cancer: systematic review and network meta-analysis
Authors: Siaw-Acheampong K , Kamarajah S K , Gujjuri R , Bundred J R , Singh P , Griffiths E A
Published: September 2020

Background

Oesophagectomy is a demanding operation that can be performed by different approaches including open surgery or a combination of minimal access techniques. This systematic review and network meta-analysis aimed to evaluate the clinical outcomes of open, minimally invasive and robotic oesophagectomy techniques for oesophageal cancer.

Methods

A systematic literature search was conducted for studies reporting open oesophagectomy, laparoscopically assisted oesophagectomy (LAO), thoracoscopically assisted oesophagectomy (TAO), totally minimally invasive oesophagectomy (MIO) or robotic MIO (RAMIO) for oesophagectomy. A network meta-analysis of intraoperative (operating time, blood loss), postoperative (overall complications, anastomotic leaks, chyle leak, duration of hospital stay) and oncological (R0 resection, lymphadenectomy) outcomes, and survival was performed.

Results

Ninety-eight studies involving 32 315 patients were included in the network meta-analysis (open 17 824, 55·2 per cent; LAO 1576, 4·9 per cent; TAO 2421 7·5 per cent; MIO 9558, 29·6 per cent; RAMIO 917, 2·8 per cent). Compared with open oesophagectomy, both MIO and RAMIO were associated with less blood loss, significantly lower rates of pulmonary complications, shorter duration of stay and higher lymph node yield. There were no significant differences between surgical techniques in surgical-site infections, chyle leak, and 30- and 90-day mortality. MIO and RAMIO had better 1- and 5-year survival rates respectively compared with open surgery.

Conclusion

Minimally invasive and robotic techniques for oesophagectomy are associated with reduced perioperative morbidity and duration of hospital stay, with no compromise of oncological outcomes but no improvement in perioperative mortality.
An adaptable dry lab for SYBR based RT‐qPCR primer design to reinforce concepts in molecular biology and nucleic acids
Authors: Covey Scott D.
Published: September 2020

The real time PCR (qPCR) method provides a powerful method to assess levels of particular species of DNA. When combined with reverse transcription (RT‐qPCR) it is the predominate technique to measure expression of gene transcripts. While this approach is very powerful, particular care must be taken in the design of the primers to facilitate specific and sensitive detection. Herein describes the framework for an undergraduate assignment which aims to teach primer design for SYBR based RT‐qPCR. Beyond gaining direct experience with primer design, students will gain familiarity with important bioinformatic resources as well as a deeper theoretical understanding of the RT‐qPCR approach and potential limitations. Moreover, as students' progress through the assignment they re‐encounter many important concepts in molecular biology, gene expression, and nucleic acids, creating an opportunity for spiral learning. As this exercise only requires access to free web‐based resources and does not require a laboratory it can be used in most science education settings. Despite not being a wet lab, this is a highly authentic research experience as this design process is commonplace in a molecular biology laboratory. Furthermore, the assignment is highly adaptable for different learning outcomes, time frames, and student background and ability. This article seeks to highlight connections and expanded learning outcomes for those already teaching such material, as well as a step‐by‐step guide for those new to teaching such content.
High neutrophil‐to‐lymphocyte ratio is a predictor of poor short‐term outcome in patients with mild acute ischemic stroke receiving intravenous thrombolysis
Authors: Liu Yong‐Lin , Wu Zhi‐Qiang , Qu Jian‐Feng , Qiu Dong‐Hai , Luo Gen‐Pei , Yin Han‐Peng , Fang Xue‐Wen , Wang Fang , Chen Yang‐Kun
Published: September 2020

Introduction

Very few studies have investigated the specific relationship between neutrophil‐to‐lymphocyte ratio (NLR) and the short‐term outcomes of patients suffering from mild acute ischemic stroke (AIS) and receiving intravenous thrombolysis (IVT). This study aimed to investigate whether a high NLR is associated with a poor short‐term outcome in patients with mild AIS after IVT.

Methods

We retrospectively analyzed data that were prospectively acquired from patients with AIS treated with IVT. Mild AIS was defined as a National Institutes of Health Stroke Scale (NIHSS) score ≤ 7 on admission. The NLR was based on a blood test performed prior to IVT and was classified as ‘high’ when exceeding the 75th percentile. Follow‐ups were performed at discharge and 3 months after onset. A poor outcome was defined as a modified Rankin scale (mRS) ≥3.

Results

A total of 192 patients were included in this study. The median NLR was 3.0 (interquartile range [IQR]: 2.0–3.9). Fifty‐one patients (26.6%) had a high NLR (≥3.9) on admission. Forty‐one patients (21.4%) had a poor outcome at discharge, while 34 patients (17.7%) had a poor outcome at 3 months. Patients with a poor outcome at discharge, and at 3 months after onset, were more likely to have a high NLR at discharge (42.9% vs. 21.9%; p = .005) and at 3 months (44.1% vs. 22.8%; p = .011), compared with those with a better outcome. After adjustment for NIHSS score on admission, ipsilateral severe intracranial large artery occlusion, and atrial fibrillation, logistic regression analyses revealed that a high NLR was a significant predictor of poor outcome at discharge and at 3 months after onset.

Conclusions

A high NLR on admission could be a useful marker for predicting poor short‐term outcome in patients with mild AIS following IVT.
Does foreign direct investment promote environmental efficiency in developing economies? Evidence from Economic Community of West African States
Authors: Awodumi Olabanji B.
Published: September 2020

Foreign direct investment (FDI) continues to play a vital role in developing economies following its ability to fill a number of gaps, chief among which is technology gap. However, the contribution of such FDI inflow to environmental quality, hence sustainable development, has been questioned severally in the literature. This study investigates the role of inward FDI in environmental efficiency among the Economic Community of West African States (ECOWAS) countries during 1980–2016. It utilizes the pollution haven (halo) hypothesis and estimated the specified model using the autoregressive distributed lag techniques for the individual countries, and random and fixed effect, as well as seemingly unrelated regression methods for the panel analysis. Findings show evidence that FDI inflow hampers environmental efficiency in all ECOWAS countries, except Sierra Leone where increased inflow of FDI promotes environmental efficiency only in the short run. Results also show that energy intensity has significant negative effect on environmental efficiency in Benin (short run), Burkina Faso, The Gambia, Mali (short run), Togo and panel of countries, suggesting that energy‐efficient technology enhances this efficiency. ECOWAS policy formulation must therefore harness the potential benefits that inward FDI brings to the community by harmonizing environmental regulations among its members in order to make the region safe and environmentally attractive to clean foreign investment. Other policy implications are derived for sustainable development of the community.