bluuebunny/crossref_metadata_2025 huggingface dataset:
A transcriptomic study for identifying cardia‐ and non–cardia‐specific gastric cancer prognostic factors using genetic algorithm‐based methods
Authors: Xin Junyi , Wu Yanling , Wang Xiaowei , Li Shuwei , Chu Haiyan , Wang Meilin , Du Mulong , Zhang Zhengdong
Published: July 2020

Gastric cancer (GC) is a heterogeneous tumour with numerous differences of epidemiologic and clinicopathologic features between cardia cancer and non‐cardia cancer. However, few studies were performed to construct site‐specific GC prognostic models. In this study, we identified site‐specific GC transcriptomic prognostic biomarkers using genetic algorithm (GA)‐based support vector machine (GA‐SVM) and GA‐based Cox regression method (GA‐Cox) in the Cancer Genome Atlas (TCGA) database. The area under time‐dependent receive operating characteristic (ROC) curve (AUC) regarding 5‐year survival and concordance index (C‐index) was used to evaluate the predictive ability of Cox regression models. Finally, we identified 10 and 13 prognostic biomarkers for cardia cancer and non‐cardia cancer, respectively. Compared to traditional models, the addition of these site‐specific biomarkers could notably improve the model preference (cardia: AUCtraditional vs AUCcombined = 0.720 vs 0.899, P = 8.75E‐08; non‐cardia: AUCtraditional vs AUCcombined = 0.798 vs 0.994, P = 7.11E‐16). The combined nomograms exhibited superior performance in cardia and non‐cardia GC survival prediction (C‐indexcardia = 0.816; C‐indexnoncardia = 0.812). We also constructed a user‐friendly GC site‐specific molecular system (GC‐SMS, https://njmu‐zhanglab.shinyapps.io/gc_sms/), which is freely available for users. In conclusion, we developed site‐specific GC prognostic models for predicting cardia cancer and non‐cardia cancer survival, providing more support for the individualized therapy of GC patients.
The endocranium and trophic ecology of Velociraptor mongoliensis
Authors: King J. Logan , Sipla Justin S. , Georgi Justin A. , Balanoff Amy M. , Neenan James M.
Published: July 2020

Neuroanatomical reconstructions of extinct animals have long been recognized as powerful proxies for palaeoecology, yet our understanding of the endocranial anatomy of dromaeosaur theropod dinosaurs is still incomplete. Here, we used X‐ray computed microtomography (µCT) to reconstruct and describe the endocranial anatomy, including the endosseous labyrinth of the inner ear, of the small‐bodied dromaeosaur, Velociraptor mongoliensis. The anatomy of the cranial endocast and ear were compared with non‐avian theropods, modern birds, and other extant archosaurs to establish trends in agility, balance, and hearing thresholds in order to reconstruct the trophic ecology of the taxon. Our results indicate that V. mongoliensis could detect a wide and high range of sound frequencies (2,368–3,965 Hz), was agile, and could likely track prey items with ease. When viewed in conjunction with fossils that suggest scavenging‐like behaviours in V. mongoliensis, a complex trophic ecology that mirrors modern predators becomes apparent. These data suggest that V. mongoliensis was an active predator that would likely scavenge depending on the age and health of the individual or during prolonged climatic events such as droughts.
A microalgal‐based preparation with synergistic cellulolytic and detoxifying action towards chemical‐treated lignocellulose
Authors: Benedetti Manuel , Barera Simone , Longoni Paolo , Guardini Zeno , Herrero Garcia Natalia , Bolzonella David , Lopez‐Arredondo Damar , Herrera‐Estrella Luis , Goldschmidt‐Clermont Michel , Bassi Roberto , Dall’Osto Luca
Published: July 2020

High‐temperature bioconversion of lignocellulose into fermentable sugars has drawn attention for efficient production of renewable chemicals and biofuels, because competing microbial activities are inhibited at elevated temperatures and thermostable cell wall degrading enzymes are superior to mesophilic enzymes. Here, we report on the development of a platform to produce four different thermostable cell wall degrading enzymes in the chloroplast of Chlamydomonas reinhardtii. The enzyme blend was composed of the cellobiohydrolase CBM3GH5 from C. saccharolyticus, the β‐glucosidase celB from P. furiosus, the endoglucanase B and the endoxylanase XynA from T. neapolitana. In addition, transplastomic microalgae were engineered for the expression of phosphite dehydrogenase D from Pseudomonas stutzeri, allowing for growth in non‐axenic media by selective phosphite nutrition. The cellulolytic blend composed of the glycoside hydrolase (GH) domain GH12/GH5/GH1 allowed the conversion of alkaline‐treated lignocellulose into glucose with efficiencies ranging from 14% to 17% upon 48h of reaction and an enzyme loading of 0.05% (w/w). Hydrolysates from treated cellulosic materials with extracts of transgenic microalgae boosted both the biogas production by methanogenic bacteria and the mixotrophic growth of the oleaginous microalga Chlorella vulgaris. Notably, microalgal treatment suppressed the detrimental effect of inhibitory by‐products released from the alkaline treatment of biomass, thus allowing for efficient assimilation of lignocellulose‐derived sugars by C. vulgaris under mixotrophic growth.
Melatonin improves cryopreservation of ram sperm by inhibiting mitochondrial permeability transition pore opening
Authors: Fang Yi , Zhao Chengzhen , Xiang Hai , Jia GongXue , Zhong Rongzhen
Published: July 2020

Cryopreservation damages permeability of sperm mitochondrial membranes, with formation of a mitochondrial permeability transition pore (mPTP). Mitochondria are both a primary synthesis site and principle target for melatonin, which can directly inhibit mPTP formation. The objective was to determine effects of melatonin on mPTP opening of frozen‐thawed ram sperm and elucidate underlying pathways by antagonist and agonists of melatonin receptors (MTs), and antagonists of PI3K and GSK 3β treatments; furthermore, plasma membrane integrity, mitochondrial membrane potential (ΔΨm), mitochondrial cytochrome c (Cyt c) release and fertilization were analysed to assess the effect of mPTP status mediated by melatonin on quality of frozen‐thawed sperm. Fresh ram semen was diluted in glucose‐egg yolk buffer with 0 or 10–7 M melatonin (frozen and frozen + melatonin groups, respectively) and slow‐frozen. In frozen‐thawed sperm, melatonin added at initiation of 4°C equilibration was most effective for inhibiting mPTP opening, decreasing peptidyl‐prolyl‐cis/trans isomerase activity of cyclophilin D and increasing plasma membrane integrity, ΔΨm, mitochondrial Cyt c concentration and fertilizing ability (p < .05). In a mechanistic study, the melatonin receptor (MT)1 antagonist eliminated inhibition of melatonin on mPTP opening, whereas MT1 agonist had opposite effects (p < .05). Neither MT2 antagonist nor agonist had significant effect, but PI3K and/or GSK 3β antagonist decreased inhibition of MT1 agonist on mPTP opening (p < .05). In conclusion, melatonin improved sperm cryopreservation, perhaps by acting on MT1 via the PI3K‐Akt‐GSK 3β pathway to inhibit mPTP opening.
Temporal aspects of affective states, physiological responses, and perceived exertion in competitive cycling time trials
Authors: Davis Paul A. , Stenling Andreas
Published: July 2020

Athletes’ affective states can vary dramatically before, during, and after competition. Further, intense affect is associated with physiological responses that may amplify biological reactions manifested from the execution of physical tasks underlying performance. Fluctuations in perceptual cues (eg, perceived exertion) and physiological responses (eg, blood lactate, heart rate) can influence performance and vary dramatically in relation to competition. However, the pattern of these fluctuations and potential associations between perceptual cues and biological responses may also diverge during task execution with differential implications for performance. Data collected from highly trained athletes (N = 25; Mage = 25.4) during a competition (ie, maximum total distance) comprised of three 7‐minute cycling time trials and were analyzed with longitudinal multilevel modeling. Results showed that affective states were negatively associated with perceived exertion at the within‐person level and negatively associated with heart rate at the between‐person level within each trial. Blood lactate and heart rate were positively associated at the between‐person level, whereas heart rate was positively associated with perceived exertion at the within‐person level. The anticipation of more pleasurable affective states predicted less decline in affective states, but not physiological responses, during each trial. Anticipated affective states prior to each trial were also associated with affective states upon its completion. These findings suggest associations among perceptual cues and physiological responses may differ depending on the level of analysis (between‐ vs. within‐person level associations), and anticipated affective states prior to performance may influence affective states during and after task execution.
Absorption of infrasound in the lower and middle clouds of Venus
Authors: Trahan Adam J. , Petculescu Andi
Published: July 2020

The paper presents predictions for the infrasonic attenuation coefficient in the clouds of Venus at altitudes of 50–60 km, where instrumented balloons will likely be deployed. The acoustic wavenumber is obtained by modifying the model of Baudoin, Coulouvrat, and Thomas [J. Acoust. Soc. Am. 130(3), 1142–1153 (2011)] to account for typical Venus cloud composition. A two-phase system, consisting of polydisperse aqueous–H2SO4 liquid droplets with a trimodal size distribution and their vapors is considered. Assuming sulfuric acid as the main condensable species, the low-frequency cloud attenuation coefficient is dominated by the evaporation/condensation of H2SO4. It ranges from 2×10−5 dB/km at 10 mHz to 0.1 dB/km at 10 Hz, exceeding that of the dry atmosphere by up to 2 orders of magnitude. Varying the cloud density by ±50% changes the attenuation by −35%/+100% at 1 mHz and ±50% at 10 Hz. The same variation in the acid vapor diffusion coefficient causes attenuation changes from −20%/+70% at 1 mHz to +25%/−40% at 10 Hz. As the evaporation coefficient of H2SO4 (presently poorly constrained) is varied from 0.01 to 1, the attenuation drops from 10−4 dB/km to 4×10−6 dB/km at 10 mHz and increases from 10−3 dB/km to 2×10−2 dB/km at 10 Hz.
MRNIP is a replication fork protection factor
Authors: Bennett L. G. , Wilkie A. M. , Antonopoulou E. , Ceppi I. , Sanchez A. , Vernon E. G. , Gamble A. , Myers K. N. , Collis S. J. , Cejka P. , Staples C. J.
Published: July 2020

MRNIP interacts directly with the MRE11:RAD50 nuclease to protect nascent DNA from degradation and consequent genome instability.
A long-lived magma ocean on a young Moon
Authors: Maurice M. , Tosi N. , Schwinger S. , Breuer D. , Kleine T.
Published: July 2020

Fitting the isotopic composition of lunar rocks to a new thermal and crystallization model shows the Moon formed 4.40 to 4.45 Ga.
Immunophenotyping of COVID-19 and influenza highlights the role of type I interferons in development of severe COVID-19
Authors: Lee Jeong Seok , Park Seongwan , Jeong Hye Won , Ahn Jin Young , Choi Seong Jin , Lee Hoyoung , Choi Baekgyu , Nam Su Kyung , Sa Moa , Kwon Ji-Soo , Jeong Su Jin , Lee Heung Kyu , Park Sung Ho , Park Su-Hyung , Choi Jun Yong , Kim Sung-Han , Jung Inkyung , Shin Eui-Cheol
Published: July 2020

Single-cell RNA sequencing of blood immune cells reveals type I interferon–associated hyper-inflammation in severe COVID-19.
Intra-articular horizontal dislocation of the patella: a rare injury and review of the literature
Authors: Despotidis Vasileios , Weihs Johannes , Joseph Zacharia , Gousopoulos Lampros
Published: July 2020

Acute traumatic intra-articular dislocation of the patella is not a common presentation in orthopaedic practice; less frequently observed than extra-articular dislocation of the patella. In some of these cases, closed reduction is not possible and an open reduction in the operating theatre must be performed. In this case report, we present an elderly patient with an intra-articular horizontal dislocation of the patella without any other bony or ligamentous lesions seen in a postreduction MRI. We conducted a literature review looking at intra-articular patella dislocations, identifying 64 published studies (articles, case reports and papers). The following sources of data were searched until December 2017: PubMed, OVID, Google Scholar, Scopus, using the search strategy of (intra-articular dislocation of patella, horizontal patellar dislocation) with no limitation on the year or language of publication. The patient presented in this case report was managed with a closed reduction under general anaesthesia, without the need of any surgical intervention. As proposed in the literature, the hypothesis of an intra-articular entrapment of the patella due to the trapped osteophytes of the superior pole of the patella into the intercondylar notch was thought to be the cause of intra-articular dislocation in this elderly patient.
Prospective randomised controlled trial using the REthinking Clinical Trials (REaCT) platform and National Surgical Quality Improvement Program (NSQIP) to compare no preparation versus preoperative oral antibiotics alone for surgical site infection rates in elective colon surgery: a protocol
Authors: Apte Sameer S , Moloo Husein , Jeong Ahwon , Liu Michelle , Vandemeer Lisa , Suh Kathryn , Thavorn Kednapa , Fergusson Dean A , Clemons Mark , Auer Rebecca C
Published: July 2020

Introduction

Despite 40 randomised controlled trials (RCTs) investigating preoperative oral antibiotics (OA) and mechanical bowel preparation (MBP) to reduce surgical site infection (SSI) rate following colon surgery, there hasneverbeen an RCT published comparing OA alone versus no preparation. Of the four possible regimens (OA alone, MBP alone, OA plus MBP and no preparation), randomised evidence is conflicting for studied groups. Furthermore, guidelines vary, with recommendations for OA alone, OA plus MBP or no preparation. The National Surgical Quality Improvement Program (NSQIP) has automated data collection for surgical patients. Similarly, the ‘REthinking Clinical Trials’ (REaCT) platform increases RCT enrolment by simplifying pragmatic trial design. In this novel RCT protocol, we combine REaCT and NSQIP to compare OA alone versus no preparation for SSI rate reduction in elective colon surgery. To our knowledge, this is the first published RCT protocol that leverages NSQIP for data collection. In our feasibility study, 67 of 74 eligible patients (90%) were enrolled and 63 of 67 (94%) were adherent to protocol. The ‘REaCT–NSQIP’ trial design has great potential to efficiently generate level I evidence for other perioperative interventions.

Methods and analysis

SSI rates following elective colorectal surgery after preoperative OA or no preparation will be compared. We predict 45% relative rate reduction of SSI, improvement in length of stay, reduced costs and increased quality of life, with similar antibiotic-related complications. Consent, using the ‘integrated consent model’, and randomisation on a mobile device are completed by the surgeon in a single clinical encounter. Data collection for the primary end point is automatic through NSQIP. Analysis of cost per weighted case, cost utility and quality-adjusted life years will be done.

Ethics and dissemination

This study is approved by The Ontario Cancer Research Ethics Board. Results will be disseminated in surgical conferences and peer-reviewed journals.

Trial registration number

NCT03663504; Pre-results, recruitment phase.
Integrating eye health training into the primary child healthcare programme in Tanzania: a pre-training and post-training study
Authors: Malik Aeesha N J , Mafwiri Mlika , Gilbert Clare , Kim Min J , Schellenberg Joanna
Published: July 2020

Objectives

To evaluate a primary child eye care training module for use in the WHO/UNICEF Integrated Management of Newborn and Childhood Illness (IMNCI) programme by primary healthcare workers.

Design

Pre-training and post-training study.

Setting

Primary healthcare facilities in a semirural district, central Tanzania.

Participants

54 primary healthcare workers selected by the Ministry of Health were trained during routine IMNCI training. All these healthcare workers were assessed pre-intervention and post-intervention. A subgroup of 40 were also assessed 6 months after the completion of training.

Intervention

Training in an IMNCI eye module, developed for child primary healthcare workers with the Tanzania Ministry of Health and eye care experts.

Main outcome measures

Knowledge, skills and attitudes were assessed using multiple choice questions, case studies and a self-assessment of skills using a Likert scale before and immediately after training, and 6 months later. A total score was derived. At 6 months, attitudes were assessed in semistructured interviews.

Results

69% PHWs trained were nurses. The baseline (before training) score was 29.9 (95% CI 27.5 to 32.4) and increased by 11.2 points (95% CI 8.3 to 14) immediately after training, and by 12.4 points (95% CI 9.2 to 15.6) at 6 months post the training. Therefore, the post-training scores increased and there was no evident difference in scores from immediately after training to 6 months later. Self-assessed confidence in skills decreased from 9/18 (95% CI 9 to 10) to 6/18 (95% CI 6 to 7). At 6 months, the module was reported as easy to understand and use, with challenges including difficulties in examining children’s eyes and poor referral systems.

Conclusions

The module increased knowledge of child eye health in primary healthcare workers, which was maintained, and was acceptable. The module has since been included into the national IMNCI health policy in Tanzania.
Current collaboration between palliative care and neurology: a survey of clinicians in Europe
Authors: Oliver David , Borasio Gian Domenico , Veronese Simone , Voltz Raymond , Lorenzl Stefan , Hepgul Nilay
Published: July 2020

Introduction

The collaboration between palliative care and neurology has developed over the last 25 years and this study aimed to ascertain the collaboration between the specialties across Europe.

Methods

This online survey aimed to look at collaboration across Europe, using the links of the European Association for Palliative Care and the European Academy of Neurology.

Results

298 people completed the survey—178 from palliative care and 120 from neurology from over 20 countries across Europe. They reported that there was good collaboration in the care for people with amyotrophic lateral sclerosis and cerebral tumours but less for other progressive neurological diseases. The collaboration included joint meetings and clinics and telephone contacts. All felt that the collaboration was helpful, particularly for maintaining quality of life, physical symptom management, psychological support and complex decision making, including ethical issues.

Discussion

The study shows evidence for collaboration between palliative care and neurology, but with the need to develop this for all neurological illness, and there is a need for increased education of both areas.
Treatment of posterior circulation non-saccular aneurysms with flow diversion versus stent-assisted coiling: a systematic review and meta-analysis
Authors: Domingo Ricardo A , Tripathi Shashwat , Perez-Vega Carlos , Vivas-Buitrago Tito , Lu Victor M , Todnem Nathan D , Quinones-Hinojosa Alfredo , Tawk Rabih G
Published: July 2020

Treatment of non-saccular aneurysms of the posterior circulation poses a great challenge with unpredictable outcomes due to the absence of a true aneurysm neck and the presence of perforating vessels. In this article, we aim to compare endovascular treatment of unruptured posterior circulation non-saccular aneurysms with stent-assisted coiling (SAC) and flow diversion (FD) in terms of occlusion rate and clinical outcomes. A systematic search of electronic databases from inception to August 2019 identified 484 articles for screening. After proper inclusion/exclusion criteria, 15 articles were included and data were extracted and analyzed using meta-analysis of proportions. The pooled cohort consisted of 430 aneurysms: 128 (29.7%) treated with SAC in 5 studies and 302 (70.3%) treated with FD in 11 studies. Complete/near-complete occlusion was achieved in 83% after FD (95% CI 0.75 to 0.90; I2=45%) and 84% after SAC (95% CI 0.72 to 0.91; I2=22%), with no significant difference between techniques (p=0.95). Periprocedural complications were observed in 18% after FD (95% CI 0.14 to 0.23; I2=0%) and 6% after SAC (95% CI 0.02 to 0.13; I2=0%); the subgroup analysis was statistically significant (p=0.008). Furthermore, no statistically significant difference was observed in favorable clinical outcomes between groups. These results suggest similar efficacy in occlusion rate and favorable clinical outcome for posterior circulation non-saccular aneurysms treated with SAC and FD. Stroke was the most common complication regardless of treatment modality, and a lower periprocedural complication rate was noted with SAC. Further studies are needed with the primary focus of reducing the risk of stroke with either modality.
Regional and local controls on Archean rock-hosted cobalt mineralization at the McAra deposit, southern Superior Province, Ontario, Canada
Authors: Hendrickson Michael D.
Published: July 2020

The McAra deposit is in eastern Ontario, Canada, and is hosted in an Archean inlier to the Paleoproterozoic Huronian basin. It is currently estimated to contain ∼2.4 million pounds of cobalt at an average grade of 1.25%. New drill data show the mineralized zone comprises glaucodot–cobaltite veins and breccias that transect a mafic–siliciclastic volcanogenic massive sulfide (VMS) deposit. The high cobalt grade and host stratigraphy at the McAra deposit contrast with five-element (Ag–Co–Ni–Bi–As) deposits at the Cobalt and Gowganda camps in the region that produced high-grade silver and by-product cobalt from veins spatially associated with Nipissing Gabbro intrusions. However, geochemical data from recent core samples alongside fluid inclusion and mineralogical data suggest the cobalt zone at McAra and the five-element veins share a similar metal assemblage and were deposited from similar fluids. The mafic–siliciclastic VMS deposit at McAra contains anomalous amounts of cobalt, suggesting the Archean host stratigraphy was the source for the high-grade cobalt zone. Basin brines in the Paleoproterozoic are interpreted to have leached cobalt from Archean rocks and then redeposited it through oxidation–reduction reactions along synvolcanic faults that controlled earlier VMS deposit formation. High-resolution aeromagnetic data show that McAra is immediately adjacent to a mafic dike that transects the Huronian basin along a northwest-striking, crustal-scale fault system. These data, alongside observations from field mapping, also suggest the deposit is on the margin of a sub-basin that contains an 80 km2 Nipissing sill that may have originally overlain the deposit area and been a hydrologic seal during mineralization. The new deposit- and regional-scale data and interpretations are used to create a model for the McAra deposit and provide evidence for why it is cobalt-rich relative to other five-element veins. The model and data can be used to guide exploration for additional cobalt-rich deposits in the region and similar settings globally.
On the new Narayana polynomials, the Gauss Narayana numbers and their polynomials
Authors: Özkan Engi̇n , Kuloğlu Bahar
Published: July 2020

We give a new definition of Narayana polynomials and show that there is a relationship between the coefficient of the new Narayana polynomials and Pascal’s triangle. We define the Gauss Narayana numbers and their polynomials. Then we show that there is a relationship between the Gauss Narayana polynomials and the new Narayana polynomials. Also, we show that there is a relationship between the derivatives of the new Narayana polynomials and Pascal’s triangle. We also explain the relationship between the new Narayana polynomials and the known Pell numbers. Finally, we give the Hankel transform of the new Narayana polynomials.
Transmission dynamics of onchocerciasis with two classes of infection and saturated treatment function
Authors: Idowu Amos Sesan , Ogunmiloro Oluwatayo Michael
Published: July 2020

A mathematical model describing the epidemic interactions between humans and blackflies in the transmission of onchocerciasis is considered. In this model, the onchocerciasis infected human individuals are divided into two classes of infected humans with high and low microfilarial output incorporating saturated treatment function, which caters for high saturation of onchocerciasis disease. We analyze the model feasible region and obtain the basic reproduction number [Formula: see text] using the next generation matrix method. Also, we obtain the onchocerciasis-free and onchocerciasis endemic equilibrium solutions and show that if [Formula: see text] is less than unity, the onchocerciasis-free equilibrium is locally and globally asymptotically stable. Furthermore, we employed a Lyapunov function to analyze the global asymptotic stability of the onchocerciasis — endemic equilibrium whenever [Formula: see text] is greater than unity. In addition, data on mass drug distribution of ivermectin drug to combat onchocerciasis prevalence in Ekiti state of Nigeria were fitted to the model. Graphical results reveal that consistent annual or bi-annual distribution of ivermectin drug in the region is effective in reducing the disease menace. Further simulations also show that public health control measures are needed to minimize infectious contact between humans and blackflies which leads to onchocerciasis infections and visual blindness.
Theoretical Understanding of and Practice Path for Building an Ecological Economic System
Authors: CHEN Hongbo
Published: July 2020

The economic system aimed at integrating industries and ecosystems is one of the five major systems for building an ecological civilization. What is an ecological economic system? It is an economic system that can keep economic growth ecologically neutral, i.e. an economic system that can maintain high-speed economic growth by following ecological and economic rules and without destabilizing ecosystems, so as to meet people’s ever-growing needs for a better life. Its features include minimum impacts on ecosystems and maximal eco-economic benefits, zero-carbon renewable energy as drivers, efficient connection between clean production and ecological industrial chains, equal stress on economical, non-waste material consumption and diversified non-material consumption. In practice, building an ecological economic system requires the establishment of a market system based on reflecting the scarcity of ecological elements, a technology support system relying on ecological innovation, a modern ecological industry system oriented to high-quality development, an investment system targeted at ecological capital gain and value realization, and a performance evaluation system guided by eco-efficiency and benefits. Besides, it is also required to establish and improve the property right system for ecological assets, study and formulates guiding policies for industries, speed up the eco-friendly reform of tax system, strengthen the innovation of green financial system and strictly observe the ecological red line.
Graphite Layer Coated on Aluminium Foil as Anti-corrosion Current Collector for Neutral Aqueous Supercapacitors
Authors: Chomkhuntod Praeploy , Sawangphruk Montree , Kongsawatvoragul Ketsuda
Published: July 2020

Neutral aqueous supercapacitors are of interest due to their many advantages such as low-cost, non-flammable, and high ionic conductivity. Interestingly, the current collector is a critical part of these devices since it can be corroded in aqueous electrolytes. The Al foil is a widely used current collector for commercial organic supercapacitors due to its low-cost. However, it is corroded in aqueous electrolytes. To address this issue, we develop the graphite coating layer on the Al current collector to suppress the corrosion of Al and the formation of an oxide-resistive film on Al in an aqueous electrolyte. The corrosion testing was confirmed by the electrochemical impedance spectroscopy (EIS). Furthermore, the electrochemical performance of the as-prepared electrodes with and without the graphite coated layer was studied by using cyclic voltammetry (CV) and galvanostatic charge/discharge (GCD). The as-prepared electrode with a graphite protective layer exhibits a higher specific capacitance as well as a higher rate capability. The capacitance fading upon increasing scan rate from 10 mV s-1 to 100 mV s-1 of graphite coated aluminium electrode was only 15%, while the capacitance of the unmodified electrode extremely faded up to 75%. The as-prepared electrode with a graphite protective layer can explicitly improve the cycling stability (retain 90 %) after 5,000 cycles at an applied current density of 1 A g-1, which is different from an unmodified electrode with rapid fading up to 55%. This finding may lead to practical neutral aqueous supercapacitors.
Flexible, Thin-Layer Solid-State Supercapacitor Based on V2O5-Graphene Composite Electrode and Ionic Liquid Gel Polymer Electrolyte for Portable Electronic Systems
Authors: Azadian Farshad , Asif Omar , Rastogi Alok C
Published: July 2020

Electrochemical and energy storage properties of vanadium oxide-graphene composite electrode based solid state supercapacitor using ionic liquid gel electrolyte over flexible stainless-steel foil substrates are discussed. The composite electrode was deposited by a simple technique of spin coating of nano-size graphene dispersed vanadium sol gel followed 300°C -6h air annealing. Graphene mitigates the low electrical resistance limitation of faradaic V2O5 while contributing double layer capacitance to the overall pseudocapacitance. The BMIMBF4 ionic liquid gel with 0.2M LiClO4 dopant acts as high ionic conductivity electrolyte and source of counter ions for redox reactions. The flexible symmetrical V2O5/graphene supercapacitor shows high specific capacitance of 650 Fg-1 and energy and power density values of 30 Wh.kg-1 and 3kW kg-1, respectively at charging potential of 1.5V. The linear charge-discharge, high Coulomb efficiency ~90% and low internal resistance support its use as power source for portable electronics with high energy storage capability.
X-Ray CT 3D Structure Measurement and Performance Evaluation of All Solid-State Lithium-Ion Battery Anode
Authors: Kodama Manabu , Komiyama Shohei , Hori Satoshi , Suzuki Kota , Kanno Ryoji , Hirai Shuichiro
Published: July 2020

X-ray computed tomography (CT) measurements with high-pressure compression and performance measurements were conducted for anode half-cells with a sulfide solid electrolyte and different volume ratios of graphite as the active material, in order to elucidate the relationship between the three-dimensional structure and performance of the anodes. The X-ray CT images were captured by a laboratory-scale CT imager and battery performance was measured using charge–discharge cycles and the current interrupt method. It was found that a high volume ratio of active material led to a decrease in the battery charging speed, because there was a decrease in connections between solid electrolyte and active material due to the aggregation of the active materials.
Effect of 2,2,6,6-Tetramethylpiperidinyl-Oxide (TEMPO) as an Electrolyte Additive and its SEI Formation on MCMB-Electrode
Authors: Lin Shawn D. , Yohannes Yonas Beyene , Hwang Bing-Joe , Wu Nae-Lih
Published: July 2020

In this study, we developed the benefit of TEMPO additive for the suppression of the solvent/additive decomposition by trapping the radicals formed. With unusual stability as a neutral radical the 2 % TEMPO as an additive into STD + 5% FEC electrolyte resulted in the modification of the interphase. Through in-situ DRIFTS results we can find out and investigate the mechanism for the decomposition of TEMPO. The studies described herein also demonstrate that MCMB-electrodes in STD + 5% FEC solution containing TEMPO additive can be utilized together with high voltage cathode.
Vanadium Transport through Cation and Anion Exchange Membranes
Authors: Darling Robert M. , Saraidaridis James D , Shovlin Christopher , Fortin Michael
Published: July 2020

Transport of vanadium ions (V2+ plus V3+) and water through Nafion® and the anion exchange membrane Fumasep FAPQ-330 were measured as functions of current density in a triple membrane cell. The amount of vanadium moving through FAPQ was an order of magnitude less than through Nafion® at all current densities. A large amount of water, -1.5 moles per mole of univalent positively charged ions, was transferred through FAPQ in the direction opposite to vanadium and current. Relatively little water moved through Nafion® at the same operating conditions.
A Stable Lithium-ion Selenium Batteries Enabled by Microporous Carbon/Se and Fluoroethylene Carbonate Additive
Authors: Aboonasr Shiraz Mohammad Hossein , Hu Yuhai , Liu Jian
Published: July 2020

Lithium-ion batteries are among the most promising rechargeable batteries, due to their exceptional power and energy characteristics. However, they cannot meet the increasing demand from end-users for higher energy density. Herein, we reported a lithium-ion selenium battery by using lithiated graphite/silicon anode and microporous carbon/Se (MPC/Se) cathode with a fluoroethylene carbonate (FEC)-containing carbonate electrolyte. FEC additive enabled a stable MPC/Se cathode due to the suppressed dissolution of polyselenides into the electrolyte and improved the mechanical stability-integrity of graphite/silicon anode, leading to the formation of stable solid electrolyte interphase (SEI) layer on both the cathode and anode surfaces. As a result, lithium-ion selenium battery delivered a high specific capacity and excellent stability. The results showed a specific capacity of 356 mAh g-1 (normalized to Se) and Coulombic efficiency of 99.9% after 125 cycles for the full cells.
(Invited) Ultrabroadband Photoconduction Response of Sub-gap Defects in Amorphous In-Ga-Zn-O Thin Film Transistors
Authors: Vogt Kyle T , Mattson George W , Wager John F , Graham Matt W
Published: July 2020

Amorphous oxide thin-film transistors (TFTs) have provided a new route to transparent, low power consumption, large-area display technology. The properties of these thin films are crucially dependent on material composition and process variations which give rise to sub-gap defect states that may act as dopants and can be used to tune the electronic properties of devices. Because these devices are sensitive to small changes in processing, there is a need for a high-throughput, reliable method for extracting sub-gap defect concentrations of amorphous oxides. We present a method, ultrabroadband photoconduction microscopy (UBPC), to extract the density of states of defects throughout the sub-gap of amorphous In-Ga-Zn-O (a-IGZO) TFTs from 0.3 - 3.5 eV. By utilizing continuously tunable, focused laser excitation, we maintain high signal-to-noise over ~5 orders of magnitude of photoconduction, while removing transfer curve drift effects by subtracting dark current in real time via lock-in amplification.
Synthesis and Performance Evaluation of Exfoliated Graphene Nanoplatelet Hydrogels As Electrodes for Supercapacitors
Authors: Mypati Sreemannarayana , Sellathurai Andrew , Kontopoulou Marianna , Docoslis Aris , Barz Dominik P.J.
Published: July 2020

In this work, we formulate highly-concentrated aqueous graphene oxide/ graphene nanoplatelet (GO/GNP) dispersions. The stability of these dispersions mainly depends on the pH and the concentrations of the dispersed phase. The graphene hydrogels that we prepare from GNP, containing a small fraction of GO, are characterized by electrical conductivity measurements, X-ray diffraction, and Raman spectroscopy. The GNP hydrogels have a better mechanical stability compared to a conventional rGO hydrogel; a 50 mg freeze-dried sample can sustain a load of 200 g of weight. A flexible supercapacitor is prepared from the GNP hydrogels. A specific capacitance of 212 F g-1 is obtained at 0.8 A g-1, which is around 30% higher than that of a comparable supercapacitor made from rGO hydrogels. Additionally, the specific capacitance at 10 A g-1 remains at almost 90% of the initial values, even after 1000 cycles.
The Interesting Complicacy of the New Age Metallic Coatings with Carbonaceous Additives
Authors: Arora Sweety , Srivastava Chandan
Published: July 2020

It has been well documented that the inertness and impermeability of graphene/graphene oxide and hydrophobicity of carbon nanotubes (CNTs) can be used to protect surfaces from degradation due to corrosion. Direct deposition of these carbonaceous materials to protect large scale structures is however impractical due to obvious high cost and instrumentation related difficulties. One other way to use such carbonaceous additives is to incorporate them in minor quantitates into conventional metallic coatings. The sensitivity of the corrosion response of the composite coatings with minor additions of the carbonaceous materials is well established but there exists a debate about the beneficial or detrimental effect of such addition. In this report, we discuss some of the interesting observations made in our work on metal-graphene/graphene oxide/CNT composite coatings and illustrate that there exists a strong correlation between the additive volume fraction and the coating microstructure which essentially governs the corrosion response.
Electrodeoxidation of Iron Oxide in Aqueous NaOH Electrolyte
Authors: Haarberg Geir Martin , Khalaghi Babak
Published: July 2020

The production of iron and steel contributes to ~10 % of global CO2 emissions. Electrolysis is an alternative route to eliminate CO2 formation. Experiments were carried out in NaOH-H2O (50-50 wt%) electrolyte with a suspension of Fe2O3 particles at ~100 °C. A rotating disk electrode was used as the cathode. Different cathode substrates of different graphite qualities and silver were used. The current efficiency for iron deposition was consistently higher than 90 %. Silver was found to be an excellent substrate for good quality deposits. Cathodes in the form of pellets of hematite were also found to be reduced to iron by electrodeoxidation in the same electrolyte. Bauxite residue is a waste product from the Bayer process to produce aluminium oxide. The high content of iron oxide makes it a candidate for electrodeoxidation in a similar way.
Effect of Added Elements into TiO2 on Oxygen Reduction Activity in Acid Media
Authors: Ishihara Akimitsu , Nagai Takaaki , Matsumoto Masashi , Arao Masazumi , Kuroda Yoshiyuki , Matsuzawa Koichi , Mitsushima Shigenori , Imai Hideto , Ota Ken-ichiro
Published: July 2020

In order to develop stable non-platinum cathodes based on titanium oxides, we investigated the effect of added elements into titanium oxide and heat-treatment temperature under reductive atmosphere on the catalytic activity of oxygen reduction reaction (ORR) in acidic media. Non-, niobium-, tantalum- and zirconium-added titanium oxides heat-treated at different temperature for 10 min under Ar containing 4% hydrogen without carbon materials were prepared to reveal the dependence of ORR activity on added elements and heat-treatment temperature. We investigated the relationship between ORR activity and physico-chemical properties such as conductivity, BET surface area, crystalline structure and electronic state. We added an appropriate mixture of the Ketjenblack with the oxide catalysts led to the electrochemical activation of the oxide surface by the formation of electron conduction networks. We revealed that the density of the low-valence state of titanium ions, Ti3+, affected ORR activity in case of niobium- and tantalum-added TiO2. In addition, crystalline distortion of anatase phase with the existence of Ti3+ of niobium- and tantalum-added TiO2 might be essential in order to show ORR activity.
One-Pot Synthesis of Nitrogen-Doped Carbon Supported Mn-Co Nanoparticles for Hydrazine Oxidation
Authors: Balčiūnaitė Aldona , Budrytė Eivilė , Vaičiūnienė Jūratė , Niaura Gediminas , Kruusenberg Ivar , Kaare Kätlin , Volperts Aleksandrs , Dobele Galina , Zurins Aivars , Tamašauskaitė-Tamašiūnaitė Loreta , Norkus Eugenijus
Published: July 2020

The nitrogen-doped carbon (N-doped C), that has a graphene-like structure, has been chosen as a support for the deposition of MnCo nanoparticles using a rapid microwave heating method with the aim to use them as the anode material for direct hydrazine fuel cells (DHFCs). For comparison, the pure Co/N-doped C and Mn/N-doped C catalysts have been synthesized under similar conditions. The structure, morphology and composition of the synthesized catalysts have been characterized using Transmission Electron Microscopy (TEM), Raman, X-ray Photoelectron Spectroscopy (XPS), Scanning Electron Microscopy (SEM) and Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES). The electrocatalytic activity of the prepared MnCo/N-doped C, Co/N-doped C and Mn/N-doped C catalysts for hydrazine oxidation has been evaluated using cyclic voltammetry.
Cobalt and Nitrogen Co-Doped Peat Derived Carbon Based Catalysts for Oxygen Reduction
Authors: Jäger Rutha , Teppor Patrick , Härk Eneli , Härmas Meelis , Adamson Anu , Paalo Maarja , Volobujeva Olga , Kikas Arvo , Kochovski Zdravko , Romann Tavo , Härmas Riinu , Lust Enn
Published: July 2020

Using different carbonization protocols, five peat derived carbon materials were synthesized. These carbons have very different surface morphology confirmed by HR-SEM and different porosities and pore size distributions obtained by N2 sorption method. The ORR activity of the peat derived carbons also differs significantly in 0.1 M HClO4 solution. Additionally, co-doping the peat derived carbons with cobalt and nitrogen enhanced their catalytic activity considerably. The most active ORR catalyst was achieved using the carbon support where the dry milled peat was mixed with ZnCl2 and pyrolyzed in Ar for 2 h at 700 °C. Interestingly, the activity of the initial carbon powder does not seem to be a clear indicator of the final activity of the M-N/C catalysts synthesized from it.
Tailoring of Electrocatalyst Inks for Performance Enhancement in Proton Exchange Membrane Fuel Cells
Authors: Bapat Shalmali , Fricke Sabrina , Kohsakowski Sebastian , Goessling Soenke , Peinecke Volker , Segets Doris
Published: July 2020

Solvent-based processing is the most favored method for the fabrication of electrocatalyst layers of proton exchange membrane fuel cells. In this process, the catalyst supported on carbon and stabilized by an ionomer is dispersed in a continuous solvent medium, forming a catalyst ink. Although the importance of ink processing has been realized, it is still governed by empiricism. To this end, we systematically investigated the effects of catalyst ink processing on the colloidal stability and the electrochemical performance of membrane electrode assemblies (MEAs). Analytical centrifugation and electron microscopy were employed to characterize the catalyst inks. It was found that high-pressure homogenization produced the most stable ink with maximum MEA performance in comparison to dispersion by ultrasonication. This study paves the way for a better understanding of the process-structure-property relationships towards the development of knowledge-based electrocatalyst inks.
Employing Non-Noble Metals as Catalysts for CO2 Electroreduction
Authors: Kumawat Adhidesh S.
Published: July 2020

CO2 electroreduction to fuels is one of the most viable solutions for tackling both issues of global warming and energy crises. It is due to the fact that products such as formic acid, methanol, etc. which are obtained by electroreduction of CO2 could be employed as hydrogen carriers or directly as fuels. This phenomenon attracts huge research towards the process and its bottlenecks for making it commercial. The major hurdles regarding catalysis of CO2 electroreduction process are low solubility of CO2 in aqueous solutions and low product yields. In our previous works, we have already demonstrated employment of gas diffusion electrodes for non–noble metal catalysts such as Pb, Bi and Sn. The usage of gas diffusion electrodes enables us to exploit three phase contact of CO2 gas – solid catalysts – liquid electrolyte and shows higher product (formate ion) yield. Additionally, we have also shown through another work that the ternary eutectics of these three non–metal catalysts employed exhibits higher activity for CO2 electroreduction than singular pure metals or any other binary or ternary alloyed compositions of metals. In this work, we want to exploit the conclusions from both the works and subject ternary alloy composition of Pb – Bi – Sn metals in gas diffusion electrode configuration for the process of CO2 electroreduction. Based on the previous two results, author believes that this would enable us to obtain higher product yield and hence better energy efficiency which would be a step forward towards sustainable development.
Insight into the Specific Adsorption Properties of Pristine Ionic Liquid: Temperature Dependent Flatband Potential Study
Authors: Patel Dipal B , Mukhopadhyay Indrajit , Chauhan Khushbu
Published: July 2020

Specific adsorption of ions of ionic liquids on an electrode plays an important role in controlling the mass and/or charge transport phenomena in electrochemical techniques. Insufficient experimental evidences put limit on wider acceptance and usage of ionic liquids in the field of energy devices. In the present study, two different photoelectrochemical cells (PECs) having configurations as (i) PbOx/Fe(CN)6
-4/-3/Pt and (ii) PbOx/[Bmim]Tf2N/Pt were utilized to provide the experimental pathway and to unveil the adsorption characteristics of ion-pairs of any ionic liquid. The photoresponse curves of PECs under chopped light illumination conditions were used to extract the flatband potential of PbOx film. The band edge positions and electron affinity of PbOx films were calculated with the help of Mott-Schottky plots. It is well known that the adsorption properties of electrolytes can be understood by calculating the point of zero charge (pHpzc). Hence, this parameter was calculated by analyzing the temperature dependent flatband potential which may further unveil the adsorption characteristics of ionic liquids. This study is an unexplored approach to get closer to the understanding of inherent properties of ionic liquids which can be of utmost interest to either basic or applied field researchers.
The Protection of Lithium Metal Enabled by LiNO3 for Lithium-Sulfur Batteries
Authors: Duangdangchote Salatan , Krittayavathananon Atiweena , Phattharasupakun Nutthaphon , Sawangphruk Montree
Published: July 2020

An insight into the role of LiNO3 additive in an ether-based electrolyte for lithium sulfur battery has been presented. Herein, we proposed a formation mechanism of solid-electrolyte interphase on the surface of lithium metal anode by using the theoretical reactive force field (ReaxFF) simulation method. The interaction between the reactive lithium metal and nitrate ions results in the formation of LixNOy clusters, distributed homogeneously in both the SEI layer and electrolyte phase. Not only can these clusters be an efficient surface protection layer of lithium metal anode but also, they can suppress the lithium polysulfides shuttle effect by adsorbing liquid lithium polysulfide intermediates.