bluuebunny/crossref_metadata_2025 huggingface dataset:
Proximate Composition and Phytochemical Properties of Fresh and Boiled Solanum torvum Consumed in East of Côte d’Ivoire
Authors: Kouadio Kouakou , Adingra Kouassi Martial-Didier , Kouadio Martin , Disseka William Kwithony , Gbotognon Oscar Jaures , Kouadio Eugène Jean Parfait
Published: September 2020

Aims: The study aimed to evaluate the nutritional and anti-nutritional factors composition of the Solanum torvum fruit.

Place and Duration of Study: Department of Food Sciences and Technology, Biocatalysis and Bioprocessing laboratory of Nangui Abrogoua University (Côte d’Ivoire), between June 2019 and March 2020.

Methodology: Proximate composition, mineral element profile and phytochemical composition of fresh and boiled S torvum berries were investigated. The S torvum fruit were harvested fresh. One part was cooked in boiling water for 25 min while the other part did not undergo any treatment. These two samples were dried in an oven at 45°C for 72 hours, ground and analyzed according to official analytical method.

Results: The results indicated that the boiling caused the loss of nutrients except moisture, fibers and lipids. It was noted a significant reduction of nutrient and anti-nutrients content of berries after boiling. Boiled berries showed a higher energy value (57.07 Kcal) than fresh ones (53.12 Kcal). Despite the boiling, S torvum berries showed high levels of polyphenols (142.54 mg GAE/100g DW (dry weight)), carotenoids (12.96 mg βCE/100g DW), vitamin C (12.03 mg/100 g FW), fibers (6.88%) and ash (7.23%). Minerals analysis of S torvum berries indicated that it is rich in potassium (2046.77 mg/100 g DW), calcium (340.92 mg/100g DW), phosphorus (238.71 mg/100g DW) and magnesium (234.97 mg/100g DW) with high predicted bioavailability for calcium, magnesium and zinc. S torvum fruit contains also iron (7.97 mg/100g DW) and zinc (8.10 mg/100g DW) which are essential for organism.

Conclusion: These data indicated that this Solanum torvum fruit consumed in East of Côte d’Ivoire could constitute a potential good source of nutrients for local population.
Resource Use Efficiency among Maize Farmers in Lere Local Government Area of Kaduna State, Nigeria
Authors: Aasa O. S. , Suleiman R. , Emeghara U. U. , Yahaya U. F. , Olagunju O. E. , Onwuegbunam N. E. , John R. Akanni- , Ganiyu L. , Omodona S. , Olukotun O.
Published: September 2020

This study was carried out to analyzed the resource-use efficiency of maize production in Lere local government area of Kaduna state. Data were collected from a sample of 100 maize farmers selected through multi-stage sampling procedure using questionnaire and data collected were analyzed using simple descriptive statistics, production function and marginal value productivity analysis. The result showed that 82% were in their working age of between 21-50 years, majority of the farmers 53% were married, 91% had formal education, in terms of farming experience, majority (68%) of the respondent had farming experience that is above one year. The linear function gave the best fit with R2 of 70.2%. Production inputs such as fertilizer and agrochemicals significantly influence maize output in the study area.  Maize production in the study area has an increasing return to scale from the sum of elasticity of production (20.439). Land, labour, fertilizer, seed and agrochemicals were underutilized in maize production. Profit could be enhanced by increasing the quantity used of land, labour, fertilizer, seed and agrochemicals inputs, as well as their timely supply. It is also recommended that  financial support  in term of accessibility to credit facilities at low interest rate be given to farmers to allow them increase output and total revenue.
Detection of Serum IgG Antibodies against Mycobacterium tuberculosis among University Athletes in Rivers State, Nigeria
Authors: Cookey T. I. , Oseni S. Adewuyi- , Okonko I. O. , Anugweje K. C.
Published: September 2020

Aim: Mycobacterium tuberculosis (MTB), the causative agent of tuberculosis, is a strictly aerobic bacterium that grows fastidiously and slow, which is among the top 10 causes of death globally and the leading cause from a single infectious agent (above HIV/AIDS). Among the deadly diseases ravaging the world, tuberculosis remains one of the commonest and deadliest. The objective of this study is to determine the prevalence of tuberculosis (TB) among the athletes of the University of Port Harcourt (UNIPORT), Rivers State, Nigeria.

Study Design:  Cross-sectional study.

Place and Duration of Study: Sports Institute, University of Port Harcourt (UNIPORT), Nigeria, between June 2012 and July 2015.

Methods: A total of 100 university athletes (51 males and 49 females, the age ranged from 15-47 years) was recruited for this study. Blood samples were collected from the athletes and analyzed for serum IgG antibodies against Mycobacterium tuberculosis. OneStep Tuberculosis (TB) rapid test was used for the detection of TB antibody (Isotypes IgG, IgM and IgA) in whole blood samples from the subjects. Commercially available ELISA based kits (manufactured by Dia.Pro, Milano, Italy) were also used.

Results: The seropositivity of TB among the athletes was 5.0%. The result of the study showed that male athletes had a higher prevalence of tuberculosis than their female counterpart (5.9% vs 4.1%). Subsequently, the age groups 15-25 years had a higher prevalence of tuberculosis (6.5%) compared to age groups 26 years and above (2.6%). A significant association existed between the athletes' ages and TB prevalence (p= 0.035) and none existed with gender (p=0.654).

Conclusion: This study confirms the presence of Mycobacterium tuberculosis-specific antibodies among university athletes. Strict surveillance of the diseases is highly recommended to curb its spread and the potential increase in Multidrug-resistance tuberculosis (MDR-TB) and Extensively drug-resistance Tuberculosis (XDR-TB) as it is highly contagious.
Determinants of Mobile Fintech Uptake in Kenyan Microfinance Sector
Authors: Ndungu Jecinta Muthoni , Moturi Christopher A.
Published: September 2020

The Kenyan microfinance sector faces many challenges such as high operation costs, increased credit risk, low visibility and poor understanding of emerging technology opportunities and risks among others. These problems are persistent due to low levels of innovation and limited uptake of digital financial technologies. This research aimed to identify the determinants that influence uptake of mobile fintech and propose an appropriate model for uptake of mobile fintech within the sector. A descriptive survey of all 30 Microfinance institutions registered with Association of Microfinance Institutions (AMFI) 2018 in Kenya was carried out. Data was collected using questionnaires from 120 respondents. Data was analyzed using descriptive and inferential statistics. Based on correlation model, this study established that technology factors (r=0.862, P<.05), environmental characteristics (r=0.387, P<.05) and organizational factors (r=0.256, P<.05) have a strong influence on the uptake of mobile fintech. Using regression model, technology factors (β=.563, P<.05), organizational factors (β=.281, P<.05) and environmental characteristics (β=.562, P<.05) all have positive and significant influence on uptake of mobile fintech. These factors include technology availability, perceived technology benefits, organization size, resources availability, and competition, regulatory and legal environment among others. Uptake of mobile fintech was found to reduce operation costs and improve business operations efficiency. Understanding of the factors derived in this study will help microfinance institutions, software developers and policy makers as they develop strategies directed at promoting successful implementation of mobile fintech.
The J‐ and G/F‐domains of the major Synechocystis DnaJ protein Sll0897 are sufficient for cell viability but not for heat resistance
Authors: Düppre Eva , Schneider Dirk
Published: September 2020

Hsp70 proteins and their Hsp40 co‐chaperones are essential components of cellular chaperone networks in both prokaryotes and eukaryotes. Here, we performed a genetic analysis to define the protein domains required for the key functions of the major Hsp40/DnaJ protein Sll0897 of the cyanobacterium Synechocystis sp. PCC6803. The expression of the N‐terminally located J‐ and G/F‐domains is essential and sufficient for the proteins’ fundamental in vivo functions, whereas the presence of the full‐length protein, containing the C‐terminal substrate‐binding domains, is crucial under stress conditions.
Circular RNAs associated with a mouse model of concanavalin A‐induced autoimmune hepatitis: preliminary screening and comprehensive functional analysis
Authors: Liu Yang , Li Zhencheng , Hao Jianheng , Chen Hao , Hou Tiezheng , Hao Huiqin
Published: September 2020

Without treatment, autoimmune hepatitis (AIH) often leads to cirrhosis, liver failure and, in some cases, death. However, the pathogenesis of AIH remains incompletely understood. Here, we explored the relationship between differentially expressed circular RNAs (DECs) and development of AIH by obtaining an expression profile of DECs in a concanavalin A‐induced AIH mouse model by microarray. In total, we identified 27 DECs; the host genes of these DECs were annotated with 140 Gene Ontology terms and 19 pathways, revealing potential roles in the metabolism of cellular ions and regulation of protein expression, as well as possible involvement in endocytosis and apoptosis. We constructed a circular RNA–microRNA network that was used to infer that a mmu_circ_0001520/mmu‐miR‐193b‐3p/MAPK10 network may be associated with the occurrence of AIH. These findings may help lay the foundation for validation of the potential roles of circular RNAs in AIH.
Association of Serum Low‐Density Lipoprotein, High‐Density Lipoprotein, and Total Cholesterol With Development of Knee Osteoarthritis
Authors: Schwager Jessica L. , Nevitt Michael C. , Torner James , Lewis Cora E. , Matthan Nirupa R. , Wang Na , Sun Xianbang , Lichtenstein Alice H. , Felson David ,   for the Multicenter Osteoarthritis Study Group
Published: September 2020

Objective

Studies suggest an association between elevated total serum cholesterol, particularly low‐density lipoprotein (LDL), and osteoarthritis (OA). The present study was undertaken to evaluate the association between total cholesterol, LDL, and high‐density lipoprotein (HDL) and risk of knee OA.

Methods

We studied participants from the Multicenter Osteoarthritis study (MOST) cohort at risk of developing knee OA. From baseline through 7 years, repeated knee radiographs and magnetic resonance images (MRIs) were obtained, and knee symptoms were queried. From baseline fasting blood samples, lipids and lipoproteins were analyzed using standard assays. After excluding participants with baseline OA, we defined 2 sets of patients: those developing radiographic OA, and those developing symptomatic OA (knee pain and radiographic OA). Controls did not develop these outcomes. Additionally, we examined worsening of cartilage loss and synovitis on MRI and of knee pain using the Western Ontario and McMaster Universities Osteoarthritis Index scale. We carried out logistic regression adjusting for age, sex, body mass index, education, baseline pain, and depressive symptoms, testing total cholesterol and lipoproteins as continuous measures, and we performed sensitivity analyses examining whether commonly used thresholds for high cholesterol, LDL, or low HDL increased risk.

Results

We studied 337 patients with incident symptomatic OA and 283 patients with incident radiographic OA. The mean age at baseline was 62 years (55% women). Neither total cholesterol, LDL, nor HDL showed a significant association with radiographic or symptomatic OA. Additionally, we found no association of these lipid measures with cartilage loss, worsening synovitis, or worsening knee pain.

Conclusion

Our data do not support an association between total cholesterol, LDL, or HDL with OA outcomes.
Fixed‐time fault tolerant control for a class of switched nonlinear systems
Authors: Yang Tingting , Li Yongming
Published: September 2020

This work addresses the fixed‐time fault tolerant control problem for nonstrict feedback switched nonlinear systems whose subsystems have chained integrators with positive odd rational powers. Besides, the powers of different channels and switched subsystems can be also possibly different. The fixed‐time fault tolerant control law is formulated after using the adding one power integrator method, homogeneous system theory, backstepping technique, nested saturation control approach, which is capable of guaranteeing the global fixed‐time stability for the resulting closed‐loop stability. A numerical simulation example is given to validate the feasibility and effectiveness of the developed control strategy.
Dynamic Tuning of Near‐Field Radiative Thermal Rectification
Authors: Chen Fangqi , Liu Xiaojie , Tian Yanpei , Zheng Yi
Published: September 2020

Taking advantage of phase‐transition and reconfigurable metamaterials, dynamic control of nanoscale thermal modulation can be achieved through the near‐field radiative thermal rectification devices. Herein, an active‐tuning near‐field thermal rectifier using reconfigurable phase‐transition metamaterials is explored. The rectifier has two terminals separated by vacuum, working under a controllable operational temperature around the critical temperature of the phase‐transition material VO2. One of the terminals is a stretchable structure made of polydimethylsiloxane (PDMS) thin film and grating consisting of various types of phase‐transition material. The effects of various inclusion forms and all the related geometric parameters are well analyzed. The controllable nanoscale thermal modulation can be achieved and the ultrahigh rectification ratios of 23.7 and 19.8, the highest values ever predicted, can be obtained for two deformation scenarios, respectively. It will shed light on the dynamic tuning of small‐scale thermal transport and light manipulation.
Sensing Applications of Atomically Thin Group IV Carbon Siblings Xenes: Progress, Challenges, and Prospects
Authors: Khan Karim , Tareen Ayesha Khan , Wang Lude , Aslam Muhammad , Ma Chunyang , Mahmood Nasir , Ouyang Zhengbiao , Zhang Han , Guo Zhongyi
Published: September 2020

The 2D graphene (G) nanosheets (NSs) discovery is amound the foremost revolutionary incidents in materials science history. This discovery has stimulated huge attention in the study of other novel 2D materials (2DMs). This trend might be called modern day “alchemy,” where the basic aim is to convert most of periodic table elements into G like 2D structures. Monoelemental, atomically thin 2DMs, called “Xenes” (“X” = group (III–VI)A elements, “ene” suffix that indicates one atom thick 2D layer of atoms) which are a newly invented family among nanomaterials. The number of predicted and experimentally synthesized 2D Xene materials of group IVA, i.e., G's siblings, has gained attention in nanosize devices. Such materials involve buckle structures that have recently been experimentally fabricated. The 2D Xene materials analog to G offer exciting potential for novel sensing applications. The group IVA Xenes, in cooperation with their ligand‐functionalized derivatives, arrange in a honeycomb lattice analogous to G but through a changeable degree of buckling. Their electronic structure ranges from trivial insulators passing via semiconductors with tunable gaps, to semimetallic, depending on substrate, chemical functionalization, and strain. In this review, different potential synthesis methods for group IVA 2D Xenes are briefly presented. A brief overview of their properties obtained theoretically and experimentally is presented, and finally their potential sensing applications are discussed.
Enhancing Long‐Term Device Stability Using Thin Film Blends of Small Molecule Semiconductors and Insulating Polymers to Trap Surface‐Induced Polymorphs
Authors: Salzillo Tommaso , Campos Antonio , Babuji Adara , Santiago Raul , Bromley Stefan T. , Ocal Carmen , Barrena Esther , Jouclas Rémy , Ruzie Christian , Schweicher Guillaume , Geerts Yves H. , Mas‐Torrent Marta
Published: September 2020

The lack of long‐term stability in thin films of organic semiconductors can often be caused by the low structural stability of metastable phases that are frequently formed upon deposition on a substrate surface. Here, thin films of 2,7‐dioctyloxy[1]benzothieno[3,2‐b]benzothiophene (C8O‐BTBT‐OC8) and blends of this material with polystyrene by solution shearing are fabricated. Both types of films exhibit the metastable surface‐induced herringbone phase (SIP) in all the tested coating conditions. The blended films reveal a higher device performance with a field‐effect mobility close to 1 cm2 V−1 s−1, a threshold voltage close to 0 V, and an on/off current ratio above 107. In situ lattice phonon Raman microscopy is used to study the stability of the SIP polymorph. It is found that films based on only C8O‐BTBT‐OC8 slowly evolve to the Bulk cofacial phase, significantly impacting device electrical performance. In contrast, the blended films stabilize the SIP phase, leading to devices that maintain a high performance over 1.5 years. This work demonstrates that blending small‐molecule organic semiconductors with insulating binding polymers can trap metastable polymorphs, which can lead to devices with both improved performance and long‐term stability.
Recent Progress in Graphene/Polymer Nanocomposites
Authors: Sun Xianxian , Huang Chuanjin , Wang Lidong , Liang Lei , Cheng Yuanjing , Fei Weidong , Li Yibin
Published: September 2020

Nanocomposites, multiphase solid materials with at least one nanoscaled component, have been attracting ever‐increasing attention because of their unique properties. Graphene is an ideal filler for high‐performance multifunctional nanocomposites in light of its superior mechanical, electrical, thermal, and optical properties. However, the 2D nature of graphene usually gives rise to highly anisotropic features, which brings new opportunities to tailor nanocomposites by making full use of its excellent in‐plane properties. Here, recent progress on graphene/polymer nanocomposites is summarized with emphasis on strengthening/toughening, electrical conduction, thermal transportation, and photothermal energy conversion. The influence of the graphene configuration, including layer number, defects, and lateral size, on its intrinsic properties and the properties of graphene/polymer nanocomposites is systematically analyzed. Meanwhile, the role of the interfacial interaction between graphene and polymer in affecting the properties of nanocomposites is also explored. The correlation between the graphene distribution in the matrix and the properties of the nanocomposite is discussed in detail. The key challenges and possible solutions are also addressed. This review may provide a constructive guidance for preparing high‐performance graphene/polymer nanocomposite in the future.
Large‐Area Single‐Crystal Graphene via Self‐Organization at the Macroscale
Authors: Ta Huy Quang , Bachmatiuk Alicja , Mendes Rafael Gregorio , Perello David J. , Zhao Liang , Trzebicka Barbara , Gemming Thomas , Rotkin Slava V. , Rümmeli Mark H.
Published: September 2020

In 1665 Christiaan Huygens first noticed how two pendulums, regardless of their initial state, would synchronize.  It is now known that the universe is full of complex self‐organizing systems, from neural networks to correlated materials. Here, graphene flakes, nucleated over a polycrystalline graphene film, synchronize during growth so as to ultimately yield a common crystal orientation at the macroscale. Strain and diffusion gradients are argued as the probable causes for the long‐range cross‐talk between flakes and the formation of a single‐grain graphene layer. The work demonstrates that graphene synthesis can be advanced to control the nucleated crystal shape, registry, and relative alignment between graphene crystals for large area, that is, a single‐crystal bilayer, and (AB‐stacked) few‐layer graphene can been grown at the wafer scale.
Near‐Infrared AIE Dots with Chemiluminescence for Deep‐Tissue Imaging
Authors: Liu Chenchen , Wang Xiuxia , Liu Junkai , Yue Qiang , Chen Sijie , Lam Jacky W. Y. , Luo Liang , Tang Ben Zhong
Published: September 2020

Near‐infrared (NIR) chemiluminescence (CL) emission is highly favorable for deep‐tissue imaging, but chemically conjugated NIR CL emitters with the aggregation‐induced emission (AIE) property for biotechnology are seldom reported. Herein, an AIE‐active NIR CL emitter, TBL, is synthesized by conjugating luminol unit with electron‐accepting benzothiadiazole and an electron‐donating triphenylamine, and subsequently TBL dots are prepared by using F127 as the surfactant. The CL emission of TBL dots can last continuously for over 60 min and can be employed for quantitative (in vitro) and qualitative (in vivo) detection of 1O2. Strikingly, the NIR CL emission can penetrate through tissues with a total thickness of over 3 cm, exhibiting significantly better performance than NIR fluorescence emission and blue CL emission. Moreover, the successful differentiation of tumor and normal tissues by TBL‐based CL imaging in vivo also paves the way for CL‐guided cancer diagnosis and surgery.
Benzodithienyl Silanes for Organic Electronics: AIE Solid‐State Blue Emitters and High Triplet Energy Charge‐Transport Materials
Authors: Bossi Alberto , Arnaboldi Serena , Castellano Carlo , Martinazzo Rocco , Cauteruccio Silvia
Published: September 2020

A novel class of benzo[1,2‐b:4,3‐b′]dithienyl (BDT) silanes 1–3 in which a tetrahedral silicon atom connects two BDT units is developed as high triplet energy 3D‐host. The photophysical and electrochemical properties of these structures are investigated, demonstrating that the peculiar features of the constituting BDT units are preserved in the corresponding silanes. All compounds display deep UV absorption (Eg = 4.10–3.52 eV) and fluorescent emission (300–400 nm for 1 and 2, and 350–450 nm for 3). Phosphorescence is observed at low temperature and the respective T1 states set at 2.65, 2.59, and 2.25 eV. Emission efficiency in solution is as high as 0.18 in 3. Compound 1 crystallizes in two monoclinic structures without relevant intra‐inter‐molecular contacts; both display similar and intriguing aggregation induced emission‐like deep blue emission (390–397 nm) with quantum yield up to 13%. A blue and a green emissive organic light emitting diode devices are realized using silane 1 as semiconductive host material. The perfect sensitization of the green Ir(ppy)3 emitter results in a device which nicely compares, in terms of efficiency, with a standard one. The blue FIrpic emitter is instead only partially sensitized on account of the too closed triplets.
Flexible Near‐Infrared InGaSb Nanowire Array Detectors with Ultrafast Photoconductive Response Below 20 µs
Authors: Li Dapan , Yip SenPo , Li Fangzhou , Zhang Heng , Meng You , Bu Xiuming , Kang Xiaolin , Lan Changyong , Liu Chuntai , Ho Johnny C.
Published: September 2020

High‐performance flexible room‐temperature near‐infrared (NIR) photodetectors are one of the important components for image sensing, data communication, environmental monitoring, and bioimaging applications. However, there is still a lack of suitable device channel materials to provide high sensitivity as well as good mechanical flexibility for photodetection, particularly operating at the optical communication wavelength of 1550 nm. In this work, highly crystalline In0.28Ga0.72Sb nanowires (NWs) are successfully grown by the two‐step chemical vapor deposition method and assembled into high‐density regular NW parallel arrays on polyimide substrates. When they are constructed into photodetectors without using any p–n junctions, they exhibit the excellent responsivity up to 1520 A W−1 and ultra‐fast response speed below 20 µs toward 1550 nm irradiation at room temperature, which constitutes a record high performance among all flexible NIR photodetectors reported in recent literature. Notably, these flexible NW parallel‐array photodetectors also display a superior mechanical flexibility and operation durability. They not only provide a stable photoresponse under illumination on–off cycles up to 1000 s, but also maintain the steady photocurrent without any significant degradation after 700 bending cycles. All these results evidently indicate the promising potential of these crystalline In0.28Ga0.72Sb NW parallel arrays for next‐generation flexible optoelectronic devices.
Emerging Nickel Catalysis in Heck Reactions: Recent Developments
Authors: Bhakta S. , Ghosh T.
Published: September 2020

The synthetic application of nickel catalysts in Heck‐coupling reactions is quite prominent and noticeable of late in organic synthesis. It shows great interest over the other transition metal catalysts due to its unique characteristic that prepares them more significantly applicable in different fields of synthetic application. The usefulness of nickel‐catalysts relies in the fact that they are abundant in nature, relatively less precious and environment friendly. Nickel plays pivotal role in different kind of Heck reactions known such as intramolecular‐, intermolecular‐, reductive‐Heck type reaction producing mainly carbocycles and hetero cycles of biological significance. Carbocyclization or hetero‐cyclization reaction occurred under optimized reaction conditions developed and come up with the formation of various structural building blocks of naturally occurring compounds. Via reductive Heck cyclization large membered ring of carbo‐ or hetero‐cyclic system was formed which performed key role as building blocks in pharmaceutical synthesis and bioactive molecule formation. Intermolecular Heck type reactions were comparatively more explored. Silyl‐Heck, carbonyl‐Heck, and other miscellaneous type reactions were covered up through nickel‐catalyzed intermolecular Heck reaction. Asymmetric versions of Heck‐ coupling reactions are also reported to proceed even with unactivated alkenes, offering molecules having quaternary stereogenic center in a regio‐ and enantioselective manner. This manuscript intends to cover these entire concepts.

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Molecular Engineering of Organic Spacer Cations for Efficient and Stable Formamidinium Perovskite Solar Cell
Authors: Song Sungwon , Yang Seok Joo , Choi Wookjin , Lee Hansol , Sung Woong , Park Chaneui , Cho Kilwon
Published: September 2020

Low dimensional (LD) perovskite materials generally exhibit superior chemical stability against ambient moisture and thermal stress than that of 3D perovskites. Recently, LD perovskite has been used as a passivation layer on the surface of 3D perovskite grains. Although various LD perovskites have been developed focusing on their hydrophobicity, the impact of crystal structure of LD perovskite on the photovoltaic performance of perovskite solar cell (PSC) is still uncertain. In this work, the effects of the structural characteristics of LD perovskites on the crystal formation of formamidinium lead triiodide (α‐FAPbI3) and on the optoelectrical properties of PSCs are elucidated. The phase‐transformation kinetics of FAPbI3 mixed with LD perovskites is studied using the Johnson–Mehl–Avrami–Kolmogorov model. It is found that the arrangement of PbI6 octahedra in the LD perovskite changes the rate of α‐FAPbI3 formation. Facilitated nucleation of α‐FAPbI3 at the LD/FAPbI3 interface results in minimal structural disorder and prolonged charge‐carrier lifetimes. As a result, the PSC with the optimized LD perovskite structure exhibits a power conversion efficiency of 21.25% from a reverse current–voltage scan, and stabilized efficiency of 19.95% with excellent ambient stability without being encapsulated.
Challenges and Strategy on Parasitic Reaction for High‐Performance Nonaqueous Lithium–Oxygen Batteries
Authors: Zhang Peng , Ding Mingjie , Li Xiaoxuan , Li Caixia , Li Zhaoqiang , Yin Longwei
Published: September 2020

The soaring demands for large‐scale energy storage devices have triggered great interest in nonaqueous lithium–oxygen batteries (LOBs), the most promising next‐generation rechargeable batteries due to their extremely high energy density, low cost, and environmental friendliness. However, serious parasitic reactions give rise to continuous consumption of cell components and accumulation of indissoluble side products, resulting in high overpotential, low rate capability, and especially limited cycle life, which hinder the commercial application of LOBs. This review focuses on comprehensively understanding the possible parasitic reactions involved at the cathode, anode, and electrolyte engendered by reactive oxygen species, impurity gasses, and singlet oxygen, while other factors that destabilize batteries such as Li dendrites, high potential, and incompatibility of cell components are also discussed. Furthermore, the corresponding strategies to inhibit or eliminate parasitic reactions and enhance the cycle stability are elaborated from the perspectives of composition regulation, microstructural design, and alternative components. It should be emphasized that the introduction of dual redox mediators and singlet quencher is crucial to achieve efficient LOBs with high capacity and prolonged cycle life. Finally, perspectives on suppressing parasitic reaction are proposed with the purpose of providing inspiration in designing stable LOBs for practical applications.
Triboelectric Nanogenerator Network Integrated with Charge Excitation Circuit for Effective Water Wave Energy Harvesting
Authors: Liang Xi , Jiang Tao , Feng Yawei , Lu Pinjing , An Jie , Wang Zhong Lin
Published: September 2020

Ocean waves are considered to be one of the most promising renewable energy sources, and harvesting such energy via triboelectric nanogenerators (TENGs) is an effective strategy toward large‐scale blue energy. However, most previous optimization schemes of TENG cannot meet the demands of practical applications. In this work, a new charge excitation circuit (CEC) with advantages of integration, high efficiency, and minimum impedance is developed specially for TENGs to harvest water wave energy. The TENG with the CEC exhibits significantly improved output performance, with a maximum power of 25.8 mW and power density of 49.3 W m−3, and a 208 times enhanced current of 25.1 mA is achieved. Furthermore, a scheme of integrating TENG network and CECs is proposed for realizing large‐scale wave energy harvesting. The charge excitation TENG network is demonstrated to successfully power a digital thermometer and a wireless communication system with mobile phone through transmitting radio frequency (RF) signals for remote environmental monitoring. This study not only offers a strategy to greatly enhance the output performance of TENG networks in water wave energy harvesting, but also provides useful guidance for constructing maritime communication platform based on blue energy toward a maritime internet of things system.
Impairment of chloroplast movement reduces growth and delays reproduction of Arabidopsis thaliana in natural and controlled conditions
Authors: Howard Mia M. , Bae Andrea , Pirani Zahra , Van Nhi , Königer Martina
Published: September 2020

Premise

The importance of chloroplast movement for plant growth in constant, controlled light and of nonphotochemical quenching (NPQ) in variable, natural light are known. Here we concurrently investigated growth and reproduction of several Arabidopsis thaliana mutants to assess the relative importance of photoprotection via chloroplast movement and NPQ.

Methods

Plants were grown outdoors (natural conditions) or in a growth chamber with variable light and chilling temperatures (controlled conditions). Phenotypic growth and reproductive variables were determined at set times before maturity in wild‐type (WT) and phot1, phot2, phot1phot2 (e.g., impaired chloroplast movement, stomatal conductance, leaf flattening), chup1 (impaired chloroplast movement), and npq1 (reduced NPQ) plants.

Results

Mutants were most adversely affected in natural conditions, with phot1phot2 and chup1 most severely impacted. These mutants bolted later and produced fewer leaves and siliques, less leaf biomass, and fewer secondary inflorescences than WT. In controlled conditions, leaf traits of these mutants were unaffected, but phot1phot2 bolted later and produced fewer secondary inflorescences and siliques than WT. For most variables, there were significant interactions between growth conditions and plant genotype. Many variables were correlated, but those relationships changed with growth conditions and genotype.

Conclusions

Phenotypic variables at the time of the harvest were strongly affected by growth conditions and genotype. In natural conditions, phot1phot2 and chup1 mutants were most adversely affected, demonstrating the importance of chloroplast movement. In controlled conditions, only phot1phot2 was consistently affected, also emphasizing the important, pleiotropic effects of phototropins. In both conditions, NPQ was less important.
SARS‐CoV‐2 infection inIndiabucks the trend: Trained innate immunity?
Authors: Chinnaswamy Sreedhar
Published: September 2020

SARS‐CoV‐2, the causative agent of COVID‐19 pandemic caught the world unawares by its sudden onset in early 2020. Memories of the 1918 Spanish Flu were rekindled raising extreme fear for the virus, but in essence, it was the host and not the virus, which was deciding the outcome of the infection. Age, gender, and preexisting conditions played critical roles in shaping COVID‐19 outcome. People of lower socioeconomic strata were disproportionately affected in industrialized countries such as the United States. India, a developing country with more than 1.3 billion population, a large proportion of it being underprivileged and with substandard public health provider infrastructure, feared for the worst outcome given the sheer size and density of its population. Six months into the pandemic, a comparison of COVID‐19 morbidity and mortality data between India, the United States, and several European countries, reveal interesting trends. While most developed countries show curves expected for a fast‐spreading respiratory virus, India seems to have a slower trajectory. As a consequence, India may have gained on two fronts: the spread of the infection is unusually prolonged, thus leading to a curve that is “naturally flattened”; concomitantly the mortality rate, which is a reflection of the severity of the disease has been relatively low. I hypothesize that trained innate immunity, a new concept in immunology, may be the phenomenon behind this. Biocultural, socioecological, and socioeconomic determinants seem to be influencing the outcome of COVID‐19 in different regions/countries of the world.
Application methods of tracers for N2O source determination lead to inhomogeneous distribution in field plots
Authors: Berendt Jacqueline , Tenspolde Arne , Rex David , Clough Tim J. , Wrage‐Mönnig Nicole
Published: September 2020

Source determination of N2O has often been performed using stable isotope incubation experiments. In situ experiments with isotopic tracers are an important next step. However, the challenge is to distribute the tracers in the field as homogeneously as possible. To examine this, a bromide solution was applied as a stand‐in tracer using either a watering can, a sprayer, or syringes to a relatively dry (25% gravimetric moisture content) or wet (30%) silt loam. After 1 h, samples were taken from three soil depths (0‐10 cm), and analyzed for their water content and bromide concentration. The application with syringes was unsuccessful due to blocked cannulas. Therefore, further laboratory experiments were conducted with side‐port cannulas. Despite a larger calculated gravimetric soil moisture difference with watering can application, more Br‐ tracer was recovered in the sprayer treatment, probably due to faster transport of Br‐ through macropore flow in the wetter conditions caused by the watering can treatment. The losses of Br‐ (33% for the watering can, 28% for the sprayer treatment) are equivalent to potential losses of isotopic tracer solutions. For application of 60 at% 15NH4+, this resulted in theoretical enrichments of 44‐53 at% in the upper 2.5 cm and 7‐48 at% in 5‐10 cm. As there was hardly any NO3‐ in the soil, extrapolations for 15NO3‐ calculated enrichments were 57‐59 at% in the upper 2.5 cm and 26‐57 at% in 5‐10 cm. Overall, no method, including the side‐port cannulas, was able to achieve a homogeneous distribution of the tracer. Future search for optimal tracer application should therefore investigate methods that utilize capillary forces and avoid overhead pressure. We recommend working on rather dry soil when applying tracers, as tracer recovery was larger here. Furthermore, larger amounts of tracer lead to more uniform distributions. Further studies should also investigate the importance of plant surfaces.
Polyvinylidene fluoride nanofibers obtained by electrospinning and blowspinning: Electrospinning enhances the piezoelectric β‐phase – myth or reality?
Authors: Azzaz Cherif M. , Mattoso Luiz H. C. , Demarquette Nicole R. , Zednik Ricardo J.
Published: September 2020

Considerable effort has been devoted to improving the properties of PVDF (polyvinylidene fluoride), arguably the most technologically important piezoelectric polymer. Electrospinning has been found to be a particularly effective method of producing PVDF nanofibers with superior piezoelectric properties due to the resulting exceptionally high fraction of the piezoelectrically active crystalline β‐phase. It is typically assumed that the high external electric fields applied during electrospinning enhance the formation of this β‐phase, with the confused literature offering various unsatisfactory mechanistic explanations. However, by comparing PVDF nanofibers produced by two different processes (electrospinning and blowspinning), we show that the electric field is entirely unnecessary; indeed, the crystallization dynamics are principally driven by the applied mechanical stress, as evidenced by structurally identical 200 nm diameter PVDF fibers produced with and without external electric fields.
A psychoanalytic perspective on victims of domestic violence and coercive control
Authors: Brandt Stephanie , Rudden Marie
Published: September 2020

Based on long clinical and forensic experience in the assessment and treatment of victims of domestic violence, the authors discuss some predisposing psychological factors that can lead to a woman's vulnerability to forming and maintaining an attachment to an abusive partner. Clinical vignettes to illustrate some kinds of observed vulnerabilities along with the authors' ideas as to their origins are presented. The authors argue that these women present with some common but hidden difficulties that may go unrecognized even in a psychoanalytic setting. This is, in part, because of our profession's lack of familiarity with the nature of domestic violence. A more nuanced understanding of the phenomenon of domestic violence is obscured by two crucial factors: first, there is an initial clinical focus on the reality of significant external obstacles to terminating these often intense bonds – even in the face of foreseeable danger to the victim and children; second, and perhaps more limiting, are psychoanalytically based assumptions about “characterological masochism” that often reflect simplistic, moralistic, misogynistic assumptions about women that continue to inform psychoanalytic theory in the area of family life. In addition, the authors discuss some of the interactions contained within the perpetrator/victim relationship that reflect and reinforce the internal liabilities observed in this group of victims.
Metabolic engineering of Pichia pastoris for malic acid production from methanol
Authors: Guo Feng , Dai Zhongxue , Peng Wenfang , Zhang Shangjie , Zhou Jie , Ma Jiangfeng , Dong Weiliang , Xin Fengxue , Zhang Wenming , Jiang Min
Published: September 2020

The application of rational design in reallocating metabolic flux to accumulate desired chemicals is always restricted by the native regulatory network. In this study, recombinant Pichia pastoris was constructed for malic acid production from sole methanol through rational redistribution of metabolic flux. Different malic acid accumulation modules were systematically evaluated and optimized in P. pastoris. The recombinant PP‐CM301 could produce 8.55 g/L malic acid from glucose, which showed a 3.45‐fold increase compared to the parent strain. To improve the efficiency of site‐directed gene knockout, NHEJ‐related protein Ku70 was destroyed, whereas leading to the silencing of heterogenous genes. Hence, genes related to by‐product generation were deleted via a specially designed FRT/FLP system, which successfully reduced succinic acid and ethanol production. Furthermore, a key node in the methanol assimilation pathway, glucose‐6‐phosphate isomerase was knocked out to liberate metabolic fluxes trapped in the XuMP cycle, which finally enabled 2.79 g/L malic acid accumulation from sole methanol feeding with nitrogen source optimization. These results will provide guidance and reference for the metabolic engineering of P. pastoris to produce value‐added chemicals from methanol.
α‐Methylene‐β‐Lactone Scaffold for Developing Chemical Probes at the Two Ends of the Selectivity Spectrum
Authors: Wang Lei , Riel Louis P. , Bajrami Bekim , Deng Bin , Howell Amy R. , Yao Xudong
Published: September 2020

The utilities of an α‐methylene‐β‐lactone (MeLac) moiety as a warhead composed of multiple electrophilic sites are reported. We demonstrate that a MeLac‐alkyne not only reacts with diverse proteins as a broadly reactive measurement probe, but also recruits reduced endogenous glutathione (GSH) to assemble a selective chemical probe of GSH‐β‐lactone (GSH‐Lac)‐alkyne in live cells. Tandem mass spectrometry reveals that MeLac reacts with nucleophilic cysteine, serine, lysine, threonine, and tyrosine residues, through either Michael or acyl addition. A peptide‐centric proteomics platform demonstrates that the proteomic selectivity profiles of orlistat and parthenolide, which have distinct reactivities, are measurable by MeLac‐alkyne as a high‐coverage probe. The GSH‐Lac‐alkyne selectively probes the glutathione S‐transferase P responsible for multidrug resistance. The assembly of the GSH‐Lac probe exemplifies a modular and scalable route to develop selective probes with different recognizing moieties.
Hemodynamic comparison of transcatheter aortic valve replacement with the SAPIEN 3 Ultra versus SAPIEN 3: The HomoSAPIEN registry
Authors: Moriyama Noriaki , Lehtola Heidi , Miyashita Hirokazu , Piuhola Jarkko , Niemelä Matti , Laine Mika
Published: September 2020

Objectives

The study aims to compare the hemodynamic and clinical outcomes of the SAPIEN 3 Ultra (S3‐Ultra) with the SAPIEN 3 (S3) system in patients who underwent transfemoral transcatheter aortic valve replacement (TF‐TAVR).

Background

The new balloon‐expandable S3‐Ultra system incorporates new features to reduce paravalvular leakage (PVL). However, the data after the S3‐Ultra implantation is very limited.

Methods

A total of 282 consecutive patients who underwent TF‐TAVR with the S3‐Ultra and the S3 were evaluated. The primary outcome of this study was to compare the incidence of ≥mild PVL after the S3‐Ultra and S3 implantation.

Results

Between June 2017 and November 2019, 141 patients with the S3‐Ultra and 141 patients with the S3 were identified with similar baseline and preprocedural imaging characteristics (mean age: 79.6 ± 6.7 years and mean aortic annulus area: 492.5 ± 91.2 mm2). In total, 83 patients (29.4%) were treated with 29‐mm valve. Predischarge echocardiography demonstrated a significantly lower incidence of ≥mild PVL (the total cohort: 7.2 vs. 22.3%, p < .001, and the cohort excluding 29‐mm valve: 4.0 vs. 21.4%, p = .03) for the S3‐Ultra. The S3‐Ultra system, especially 20‐, 23‐, and 26‐mm valve, was associated with significantly lower risk of ≥mild PVL compared with the S3 system in multivariate analysis. There were no significant differences in clinical outcomes at 30‐day between these groups, except for the lower incidence of major vascular complication (4.5 vs. 11.4%, p = .05) in patients with the S3‐Ultra.

Conclusions

In this registry, the S3‐Ultra system performed superiorly to the S3, as demonstrated by reduced ≥mild PVL, with comparable safety.
Standardized fractal bench test evaluation of coronary stents: Performances in bifurcation lesions treated by the re‐proximal optimization technique
Authors: Piriou Pierre‐Guillaume , Bonin Mickael , Huchet Francois , Letocart Vincent , Manigold Thibaut , Plessis Julien , Derimay Francois , Veziers Joelle , Jordana Fabienne , Guerin Patrice
Published: September 2020

Background

Bifurcation lesions in coronary arteries are complex to treat with coronary stents, which are not designed for that purpose and can be unproperly deployed. Moreover, devices are constantly evolving, and so are angioplasty techniques.

Objectives

The aim of this study was to determine the performances of different stents in the treatment of bifurcation lesions using the re‐proximal optimization technique (rePOT).

Methods

Eleven stent platforms were evaluated: Xience Sierra (Abbott), Xience Alpine (Abbott), Synergy (Boston), Coroflex Isar (Bbraun), Cobra PzF (Celonova), Ultimaster (Terumo), Resolute Integrity (Medtronic), Resolute Onyx (Medtronic), Optimax (Hexacath), Orsiro (Biotronik), and Absorb (Abbott). Stents were deployed in a silicone fractal bifurcation model using the rePOT. Micro‐computed tomography was performed to assess side branch ostium coverage and strut malapposition, as well as the effect of rePOT on stent cell area.

Results

Our study showed significant differences between stent platforms regarding side branch ostium coverage (p = .002). The Synergy and Cobra PzF stents were the most performant devices to avoid ostium coverage. Strut malapposition varied significantly between devices (p = .008) but the percentage of malapposed struts was relatively low. Significant differences were observed between stents regarding the cell area before (p = .002) and also after rePOT (p = .003), and the increase in cell area caused by rePOT varied considerably between devices (p = .08).

Conclusion

This study highlighted significant differences in the performances of stent platforms deployed in a fractal bifurcation model using rePOT, with a variable impact of the procedure on stent cell area.
Novel Electrocatalyst for Alkaline Membrane Water Electrolysis
Authors: Mandal Mrinmay
Published: September 2020

The production of H2 has aroused considerable attention worldwide as a renewable and sustainable energy source for domestic, industrial, and automotive purposes. Currently, about 95 % of H2 is produced from the steam reforming of methane. However, this process leads to the burning of fossil fuels and emits greenhouse gases into the atmosphere. Water electrolysis is an effective strategy to produce H2 in high purity. Alkaline anion exchange membrane water electrolysis (AAEMWE) is preferred to proton exchange membrane water electrolysis (PEMWE) because of the flexibility to be able to use cheaper membranes as separators and non‐noble electrocatalysts. However, the sluggish oxygen evolution reaction (OER) kinetics in AAEMWE is a bottleneck for water splitting efficiency and decreases the overall performances. Now, a novel nickel and iron graphene‐nanoplatelets‐supported metal‐organic framework‐based electrocatalyst has been developed that shows excellent durability and record‐high current density for alkaline electrolysis that outperforms the state‐of‐the‐art OER electrocatalysts.