bluuebunny/crossref_metadata_2025_split huggingface dataset:
Process optimization of microwave irradiation‐aided transesterification of kariya seed oil by Taguchi orthogonal array: pawpaw trunk as a novel biocatalyst
Authors: Fadara Olubukola A. , Falowo Olayomi A. , Ojumu Tunde V. , Betiku Eriola 
Published: February 2021

AbstractThis study investigated the potential application of an active biocatalyst from pawpaw (Carica papaya) trunk for the direct microwave irradiation‐aided transesterification of kariya (Hildegardia barteri) seed oil (KSO) with methanol to obtain biodiesel. The transesterification process involved was modeled, and the effects of the essential process input variables on the kariya seed oil methyl ester (KSOME) yield were examined, followed by the optimization of the input variables to maximize the KSOME yield, using the Taguchi orthogonal array design method. The biocatalyst was produced with a calcination process in a muffle furnace at 200–1000 °C, and each sample obtained was characterized by a scanning electron microscope equipped with energy‐dispersive X‐ray spectroscopy (SEM–EDX) to determine the best temperature. The calcined pawpaw trunk ash (CPTA) produced at the best temperature of 400 °C was further characterized using X‐ray diffraction (XRD), Fourier‐transform infrared (FTIR) spectroscopy, and physisorption analyses. The CPTA at 400 °C produced a strong catalytic activity due to its morphology, metallic composition (K (23.85%), and Ca (15.40%)), crystalline structure, the average pore size of 32.2 nm, and a surface area of 0.64 m2 g−1. The best operating conditions established for the transesterification process were a methanol / KSO molar ratio of 10.5:1, CPTA loading of 0.5 wt%, microwave heating power of 300 W, and reaction time of 2 min, with a maximum KSOME yield of 98.50 ± 0.60 wt%. The quality of the KSOME produced satisfied the American standard specifications for biodiesel. Both KSO and pawpaw trunk could serve as inexpensive feedstock for sustainable and renewable production of biodiesel. The intensification of the transesterification process using microwave irradiation drastically shortened the reaction time needed for maximum biodiesel yield. © 2021 Society of Chemical Industry and John Wiley & Sons, Ltd
Miniature auto‐perfusion bioreactor system with spiral microfluidic cell retention device
Authors: Yin Lu , Au Wen Y. , Yu Chia C. , Kwon Taehong , Lai Zhangxing , Shang Menglin , Warkiani Majid E. , Rosche Roger , Lim Chwee T. , Han Jongyoon 
Published: February 2021

AbstractMedium perfusion is critical in maintaining high cell concentration in cultures. The conventional membrane filtration method for medium exchange has been challenged by the fouling and clogging of the membrane filters in long‐term cultures. In this study, we present a miniature auto‐perfusion system that can be operated inside a common‐size laboratory incubator. The system is equipped with a spiral microfluidic chip for cell retention to replace conventional membrane filters, which fundamentally overcomes the clogging and fouling problem. We showed that the system supported continuous perfusion culture of Chinese hamster ovary (CHO) cells in suspension up to 14 days without cell retention chip replacement. Compared to daily manual medium change, 25% higher CHO cell concentration can be maintained at an average auto‐perfusion rate of 196 ml/day in spinner flask at 70 ml working volume (2.8 VVD). The auto‐perfusion system also resulted in better cell quality at high concentrations, in terms of higher viability, more uniform and regular morphology, and fewer aggregates. We also demonstrated the potential application of the system for culturing mesenchymal stem cells on microcarriers. This miniature auto‐perfusion system provides an excellent solution to maintain cell‐favorable conditions and high cell concentration in small‐scale cultures for research and clinical uses.
Improving the activity and thermostability of GH2 β‐glucuronidases via domain reassembly
Authors: Liu Mingzhu , Yu Jing , Lv Bo , Hou Yuhui , Liu Xinhe , Feng Xudong , Li Chun 
Published: February 2021

AbstractGlycoside hydrolase family 2 (GH2) enzymes are generally composed of three domains: TIM‐barrel domain (TIM), immunoglobulin‐like β‐sandwich domain (ISD), and sugar‐binding domain (SBD). The combination of these three domains yields multiple structural combinations with different properties. Theoretically, the drawbacks of a given GH2 fold may be circumvented by efficiently reassembling the three domains. However, very few successful cases have been reported. In this study, we used six GH2 β‐glucuronidases (GUSs) from bacteria, fungi, or humans as model enzymes and constructed a series of mutants by reassembling the domains from different GUSs. The mutants PGUS‐At, GUS‐PAA, and GUS‐PAP, with reassembled domains from fungal GUSs, showed improved expression levels, activity, and thermostability, respectively. Specifically, compared to the parental enzyme, the mutant PGUS‐At displayed 3.8 times higher expression, the mutant GUS‐PAA displayed 1.0 time higher catalytic efficiency (kcat/Km), and the mutant GUS‐PAP displayed 7.5 times higher thermostability at 65°C. Furthermore, two‐hybrid mutants, GUS‐AEA and GUS‐PEP, were constructed with the ISD from a bacterial GUS and SBD and TIM domain from fungal GUSs. GUS‐AEA and GUS‐PEP showed 30.4% and 23.0% higher thermostability than GUS‐PAP, respectively. Finally, molecular dynamics simulations were conducted to uncover the molecular reasons for the increased thermostability of the mutant.
The variation in the levels of 18 amino acids in the cortex and plasma of cerebral ischemia C57BL/6 mice
Authors: Li Jian‐Sha , Qiu Hong‐mei , Jiang Qing‐song , Liu Yong‐hong , Zhang Jing , Gong Tao , Jiang Xin‐hui 
Published: February 2021

AbstractEmerging evidence suggests that amino acid (AA) neurotransmitters play important roles in the pathophysiological processes of cerebral ischemia. In this work, an HPLC with fluorescence detection (HPLC‐FLR) method was developed for the simultaneous determination of 18 AAs in the cortex and plasma after cerebral ischemia in mice. The ischemia model was prepared by bilateral common carotid artery occlusion, and then the cortex and plasma of the sham, ischemia, and naringenin groups were collected. Based on the protein precipitation method, a simple and effective sample preparation method was developed. The treated sample contained minimal proteins and lipids. The analysis of the sample was performed by the proposed HPLC‐FLR method in combination witho‐phthalaldehyde. The results showed a statistically significant increase in excitatory AAs (aspartic acid and glutamic acid), inhibitory AAs (glycine and 4‐aminobutyric acid), phenylalanine, citrulline, isoleucine, and leucine levels, and a decrease of glutathione and phenylalanine levels when compared with the sham group in the cortex. Besides, the administration of naringenin had significant effects on excitatory AAs, inhibitory AA (glycine), glutamine, tyrosine, phenylalanine, and leucine levels when compared with the sham group in the cortex. These findings could be utilized in studying and clarifying the mechanisms of ischemia.
Accentuating the interconnection between business sustainability and organizational performance in the context of the circular economy: The moderating role of organizational competitiveness
Authors: Sarfraz Muddassar , Ivascu Larisa , Belu Radian , Artene Alin 
Published: February 2021

AbstractSustainability development has gained significant importance in the modern business environment. The primary objective is to conduct an explanatory and quantitative study of the impacts of the social, economic, and environmental dimensions on organizational performance, considering the moderating role of organizational competitiveness. Data were collected from Chinese, Italian, and Romanian small and medium enterprises (SMEs). The questionnaires were distributed by applying simple random sampling techniques. The study sample size consists of 320 SME employees. Hierarchical regression was used to investigate the moderating impacts of organizational competitiveness on the relationships of the social, economic, and environmental dimensions and organizational performance. The regression analysis shows a positive relationship between the study variables. Small and medium‐sized enterprises are focusing more on sustainable business practices.
Larotrectinib in a NTRK‐rearranged soft tissue sarcoma in the neoadjuvant setting: A case report
Authors: Percy Catherine , Schubert Thomas , Galant Christine , Kirchgesner Thomas , Mazzeo Filomena 
Published: February 2021

AbstractPatients with soft tissue sarcomas should be assessed for neurotrophic tropomyosin receptor kinase (NTRK) gene fusions as neoadjuvant treatment with larotrectinib may prevent amputation.
Investigation of Bubble Behavior in Gas‐Solid Fluidized Beds with Different Gas Distributors
Authors: Jang Kwangbyol , Feng Yali , Li Haoran 
Published: February 2021

AbstractThe behavior of gas bubbles in a gas‐solid fluidized bed was investigated by computational fluid dynamics simulation. A two‐phase flow model incorporating the kinetic theory of granular flow was used to study the effect of gas distributor design on the size distribution and the rise velocity of gas bubbles in the bed column. The experiments were conducted on four gas distributors with different orifice sizes and pitches. The geometry of the gas distributor had a significant influence on the bubble behavior in the gas‐solid fluidized bed. The effects of static bed height and superficial gas velocity were also considered. Bubble diameter and bubble rise velocity increased with gas velocity. However, at low bed height, the deviation in bubble size was indistinct because at higher gas velocity the rising tendency of the bubble formed just above the gas distributor increased and the probability of bubble coalescence decreased.
Peptization Control of Composite Materials Containing Water Glass for Spray Drying of Catalysts
Authors: Saavedra Andres Carrasco , Seifert Markus , Hannß Mariella , Henle Thomas , Lê-Anh Mai , Busse Oliver , Weigand Jan J. 
Published: February 2021

AbstractSilica‐based composite particles are complex catalyst materials that are widely used in petrochemistry. The preparation of particles that are well defined in form, composition, and chemical and rheological behavior by spray drying of suspensions remains an important industrial challenge. Here, zeolite HY, kaolin, and the cheap binder water glass are used. Experimental and model regimes of slurry peptization are analyzed based on their pH value, zeta potential, and mixing speed to control the process. The results show a pseudoplastic behavior of the silica slurries for zeta potential below 20 mV, which is explained by surface charge, hydroxyls, and pH‐dependent coagulation. Thus, a quick acidification of the slurry, additional mechanic shear, and subsequent pH control during spray drying enable control of peptization kinetics.
Study of Heat and Mass Transfer by Bionic Fractal Microchannel Plates
Authors: Niu Yating , Huang Pingnan , Pan Minqiang 
Published: February 2021

AbstractBionic fractal microchannel plates are becoming popular because of their low pressure drop and high heat‐transfer efficiency. But there is still no systematic research on the heat and mass transfer mechanism of bionic fractal microchannel plates, which has limited their widespread use. A mathematical model of heat and mass transfer in bionic fractal microchannel plates is developed and the influences of their structural parameters on heat and mass transfer are evaluated. The results provide a systematic knowledge of bionic fractal microchannel plates which may help to guide their optimization for practical applications.
Ionomer Thin‐Films by Electrochemical Synthesis: Bipolar and Ampholytic Membranes
Authors: Pasquini Luca , Di Vona Maria Luisa , Sgreccia Emanuela , Ruzimuradov Olim , Knauth Philippe 
Published: February 2021

AbstractThin‐films of cation‐conducting poly(styrene sulfonate) (PSS) and anion‐conducting poly(N‐vinyl‐N‐benzyl‐N,N,N‐trimethylammonium chloride) (PVBTMA) were electrochemically deposited. A low film thickness can be obtained, because the electrodeposition is a self‐limiting process. Various cases were explored: i) the deposition of a single ionomer layer on various substrates, ii) the sequential deposition of the ionomers giving a bipolar membrane, and iii) the co‐deposition of the ionomers giving an ampholytic membrane. The structure and microstructure of the thin films were investigated by NMR spectroscopy and optical and scanning electron microscopy (SEM). Impedance spectroscopy in through‐plane configuration revealed a large resistance of the bipolar membrane, due to the ionic blocking interface between the ionomers. The ampholytic membrane also showed a low conductivity, probably due to the loss of ionic carrier pairs that can leave the ionomer without break of electroneutrality.
(Fe,Ni)9S8 Nanosheets on a Three‐Dimensional Conductive Substrate for Efficient Oxygen Evolution Reaction Electrocatalysis
Authors: Shi Bu‐Yan , Huang Yuan , Jiang Li‐Wen , Chowdhury Mahabubur , Liu Hong , Wang Jian‐Jun 
Published: February 2021

AbstractThe development of low‐cost and high‐efficiency electrocatalysts for the oxygen evolution reaction (OER) is essential for a number of applications in the field of energy conversion and storage. Herein, we present an efficient OER electrocatalyst in the form of thin (Fe,Ni)9S8 nanosheets (FNS NSs) anchored on a three‐dimensional (3D) conductive substrate of Fe/Fe3O4 nanoislands/carbon cloth (Fe NIs/CC). The resulting electrode exhibits an impressive OER performance with a low overpotential of 147 mV at 10 mA cm−2 and a Tafel slope of 29.8 mV dec−1 in 1 M KOH alkaline solution. The enhanced performance is ascribed to the thin nanosheet structure with ample active sites, the high conductivity of the substrate, and the 3D structure, which endow the electrode with a large specific surface area and more catalytic active sites. Study of the kinetic process reveals that the incorporation of Fe from the substrate can reduce the kinetic barrier of OER, allowing for a faster reaction rate.
Mathematical modelling of hydrothermal performance for Kenics type static mixer using power law obeying fluids
Authors: Mukherjee Joydeb , Pandit Aniruddha B. 
Published: February 2021

AbstractIn this study, analytical, numerical, and experimental works are presented to demonstrate hydrothermal characteristics of a flow choosing non‐Newtonian behaviour through a Kenics type static mixer. Experiments are conducted by varying the superficial fluid velocities of the heterogeneous mixture oil with Sudan dye and water, as well as for the homogeneous aqueous system, consisting of CMC (2 wt%) in water. Six static mixing elements are placed in series, and the corresponding wall temperatures of the inline pipe are varied over a range of 293–363 K. In the context of hydrodynamic study, analytical models are solved using the Bessel function and Laguerre function and validated with the in‐house experimental results and numerical results. In the thermal performance study, mathematical models are formulated based on differential transformation method (DTM) and homotopy perturbation method (HPM), and have been validated with the numerical results. The deviation among the experimentally measured average pressure drops estimated from our experiment and that predicted by analytical models is found to be as low as ±8.1%. The deviation between the analytical results obtained from the HPM and DTM method and numerical results based on the finite volume method solution of the same equation is observed as low as ±4%. Additionally, both proposed analytical methods used are compared with each other to evaluate the dimensionless swirl flow velocity and temperature gradient of the inline Kenics Static mixer. In the thermal performance study, we observe that the DTM is in good agreement with the numerical method as compared to HPM.
Recent Progress in Extending the Cycle‐Life of Secondary Zn‐Air Batteries
Authors: Prakoso Bagas , Mahbub Muhammad Adib Abdillah , Yilmaz Meltem , Khoiruddin  , Wenten I. Gede , Handoko Albertus Denny , Sumboja Afriyanti 
Published: February 2021

AbstractSecondary Zn‐air batteries with stable voltage and long cycle‐life are of immediate interest to meet global energy storage needs at various scales. Although primary Zn‐air batteries have been widely used since the early 1930s, large‐scale development of electrically rechargeable variants has not been fully realized due to their short cycle‐life. In this work, we review some of the most recent and effective strategies to extend the cycle‐life of Zn‐air batteries. Firstly, diverse degradation routes in Zn‐air batteries will be discussed, linking commonly observed failure modes with the possible mechanisms and root causes. Next, we evaluate the most recent and effective strategies aimed at tackling individual or multiple of these degradation routes. Both aspects of cell architecture design and materials engineering of the electrodes and the electrolytes will be thoroughly covered. Finally, we offer our perspective on how the cycle‐life of Zn‐air batteries can be extended with concerted and tailored research directions to pave the way for their use as the most promising secondary battery system of the future.
Optimizing bitmap index encoding for high performance queries
Authors: Yildiz Beytullah 
Published: February 2021

SummaryMany sources such as historical archives, sensor readings, health systems, and machine records produce ever‐increasing but often unchanging data. These accumulating data create a need for faster processing. Bitmap index, which can take advantage of multi‐core and multiprocessor systems, is designed to process data that increase over time but do not change frequently. It has a well‐known advantage, especially in queries on data with low cardinality. However, bitmap index can handle high cardinality data efficiently because it can use its own compression algorithm. Bitmap index has many encoding schemes that affect query processing time. In this study, we developed an algorithm that improves query performance by using optimal encoding among bitmap encodings. With this optimization algorithm, we witnessed up to 40% performance increase in queries made with bitmap indexes created with different encodings. Furthermore, in comparison with a commonly used relational database, we found significant improvements in the number of query operations per second performed on optimized encoded bitmap indexes generated by the introduced algorithm.
Graphitic Carbon Nitride (g‐C3N4) Nanosheets as a Multipurpose Material for Detection of Amines and Solar‐Driven Hydrogen Production
Authors: Vu Manh Hiep , Nguyen Chinh Chien , Do Trong‐On 
Published: February 2021

AbstractGraphitic carbon nitride nanosheets decorated by multiple functional groups (denoted as CN−KNa) were as a multipurpose material, both in photocatalytic applications and as a photo‐induced indicator. The presented g‐C3N4 is fabricated via a facile alkali‐salt‐assisted calcination method. The structural analysis reveals significant changes in the structure of the host CN−KNa nanosheets associated with the existence of multiple functional groups (for example, hydroxy, carbonyl, and cyano groups). Such modifications lead to enhanced light absorption and charge separation, resulting in an efficient photocatalyst not only for solar‐driven hydrogen production but also for primary amine detection in aqueous solution. Thus, the solar light driven photocatalytic hydrogen evolution yield using the synthesized CN−KNa sample is found to be 50.3 μmol h−1, which is approximately 14 times higher than that of bulk g‐C3N4. More importantly, this functional‐group‐decorated CN−KNa facilitated electron transportation between CN−KNa and amine compounds, causing a colour change in the solution mixture, which has been observed for the first time. This novel observation indicates that CN−KNa can be considered a new class of photo‐induced indicator agent to detect primary amine compounds in aqueous solution.
The higher they climb, the harder they fall: The role of self‐brand connectedness in consumer responses to corporate social responsibility hypocrisy
Authors: Baghi Ilaria , Antonetti Paolo 
Published: February 2021

AbstractPast research shows how information about corporate irresponsibility that contradicts an organization's social responsibility commitments causes hypocrisy perceptions. Extant research on stakeholder engagement however, has not explained how inconsistent corporate social responsibility (CSR) information affects the perceptions of consumers strongly connected with a brand. This study investigates how, rather than protecting the firm against hypocrisy perceptions, self‐brand connectedness magnifies the negative effect of inconsistent CSR information. We tested the research hypotheses across two experimental studies, using both fictitious and real brands in two different industries. We estimated a multi‐group structural equation model model to show how self‐brand connectedness increases people's willingness to distance themselves from the hypocritical brand. Results show that consumers that feel close to the hypocritical brand have a stronger desire to disengage their identity from the brand and protect their self‐esteem. The desire to avoid the brand in turn drives more negative consumer reactions in terms of brand attitudes, brand loyalty and negative word of mouth. Our findings contribute to the literature by demonstrating that a close relationship between the consumer and the brand may aggravate behavioral reactions to hypocrisy perceptions. This is the first study to consider how hypocrisy perceptions influence attitude and behaviors of consumers that are closely connected to the company. Our results extend research on hypocrisy perceptions and brand avoidance by showing that closely connected consumers are especially likely to reject brands that send inconsistent messages about their involvement in CSR.
Pericardial metastasis from alveolar rhabdomyosarcoma: A case report
Authors: Straccia Patrizia , Martini Maurizio , Pierconti Francesco 
Published: February 2021

AbstractAlveolar rhabdomyosarcoma (ARMS) commonly occurring in children and adolescents, is a rare and aggressive soft tissue malignancy demonstrating rapid growth and dissemination. Although their histopathologic and immunohistochemical findings are well known, cytomorphological features on serous effusions have not been well documented. A case of metastatic rhabdomyosarcoma diagnosed on cytological examination of the pericardial fluid cytology and discuss the diagnostic difficulties that were encountered in this case has been presented.
A comparative study between outcomes of an in‐person versus online introductory field course
Authors: Race Alexandra I. , De Jesus Maria , Beltran Roxanne S. , Zavaleta Erika S. 
Published: February 2021

AbstractThe COVID‐19 pandemic has disrupted many standard approaches to STEM education. Particularly impacted were field courses, which rely on specific natural spaces often accessed through shared vehicles. As in‐person field courses have been found to be particularly impactful for undergraduate student success in the sciences, we aimed to compare and understand what factors may have been lost or gained during the conversion of an introductory field course to an online format. Using a mixed methods approach comparing data from online and in‐person field‐course offerings, we found that while community building was lost in the online format, online participants reported increased self‐efficacy in research and observation skills and connection to their local space. The online field course additionally provided positive mental health breaks for students who described the time outside as a much‐needed respite. We maintain that through intentional design, online field courses can provide participants with similar outcomes to in‐person field courses.