bluuebunny/crossref_metadata_2025 huggingface dataset:
The Physiognomy of Flooding and Flood Disasters in Nigeria: Stakeholders’ Perception of Flooding Events of Ogbaru in Anambra State
Authors: Ezeokoli F. O. , Okolie K. C. , Aniegbuna A. I.
Published: March 2019

Aim: This study evaluates and establishes the nature and characteristics of flooding and flood disaster in Ogbaru.

Study Design: It was a survey research, where questionnaires were distributed to heads of the selected households and building practitioners in the study area. Likewise, physical observations were carried out to substantiate the findings of the questionnaire survey.

Place and Duration of the Study: The study was conducted in Ogbaru Local Government Area, Anambra State, Nigeria for a period of 2 years.

Methodology: Data were collected through structured questionnaire administered to the selected building construction practitioners and occupants in Ogbaru. In addition, interviews and direct observation survey were conducted to substantiate the validity of the questionnaire. Accordingly, a total of three hundred and eighty-four (384) questionnaires were distributed and a total of two hundred and ninety-three (293) questionnaires were completed and returned. This corresponds to a response rate of 76.3%.  Data collected were analyzed using mean score, standard deviation and t-test.

Results: The survey found that flooding is a regular phenomenon for the last five years in Ogbaru with a depth ranging from medium to shallow and not more than 1.8 m deep. The velocity of flow is either laminar or moderate but not up to 3m/s in nature while the intensity of flow & destruction significantly varies across the local government area. The flood disaster lasts for more than a month in most areas and moves with floating debris lowering the ground surface and removing refilled earth of the foundation of buildings. Over 90% of the residents of Ogbaru had experienced flood hazards which have affected their houses and those of their neighborhood.

Conclusion: The study concluded by recommending that the nature and characteristics of flooding in the study area should be thoroughly examined and considered before any construction/ mitigation action will be deployed in Ogbaru.
Time - Temperature Combination of Ohmic Heating System for Parboiling of Paddy
Authors: Patel Aaradhana , Singh Mohan , Rai A. K. , Khan M. A. , Garg S. K.
Published: March 2019

The technique for parboiling of paddy through ohmic heating was one of the best and fastest technique, which takes minimum time for complete a process due to high voltage of electric current. The aim of this study was to define the time & temperature combination of ohmic heating system for parboiling of paddy. The parboiling of paddy was a hydrothermal treatment, given prior to milling process of paddy and the methodology, applied for parboiling of paddy through ohmic heating setup was carried out in three steps, i.e. soaking, steaming and drying of parboiled paddy. The result was found after study, the temperature and time profiles of parboiled paddy through ohmic heating at different voltage gradients i.e., 15.71, 16.07, 16.43, 16.79 and 17.14 V/cm up to temperature of 96°C for paddy and water mixture of 1:3, (500g paddy and 1500ml of water). The best result was found on 17.4 V/cm (voltage gradient) at 96°C temperature for 136 min and after milling of parboiled paddy the recovery of head rice yield was found 85.63 percent. So it was the most advantageous aspect for parboiling of paddy through ohmic heating for increase the head rice yield and reduce the breakage percentage of rice kernel.
Isolation and Characterization of Bergapten from the Root Bark of Ficus exasperata (Vahl)
Authors: Famobuwa O. E. , Agbowuro A. A. , Adekunbi E. A. , Akinwale M. A.
Published: March 2019

Despite the wide ethnomedicinal applications of Ficus exasperata, little is known about the active principles responsible for the observed biological effects, thus limiting opportunities for further therapeutic applications. The bioassay guided chemical investigation of F. exasperata root bark resulted in the isolation of a furocoumarin (D-1) shown to be partly responsible for the acclaimed anti-diabetic effect of the plant.
Effect of Indole Acetic Acid and Boron on the Nutrient Contents of Summer Tomato Cultivar Bina Tomato-3
Authors: Saha Munmun , Chowdhury Md. Abul Khair , Chowdhury Md. Akhter Hossain
Published: March 2019

A pot experiment was carried out with tomato variety BINA Tomato-3 in the net house of the Department of Agricultural Chemistry, Bangladesh Agricultural University (BAU), Mymensingh from March to August, 2010 to study the effect of Indole Acetic Acid(IAA) and Boron(B) on the nutrient contents of BINA Tomato-3. There were four doses of IAA viz. 0, 20, 40 and 60 ppm and B viz. 0, 1.5, 2.0 and 2.5 kg ha-1. The experiment was laid out in a Completely Randomized Design (CRD) with 3 replications. The result revealed that nutrient contents of tomato fruits and plants such as N, P, Ca, Mg and B were significantly influenced by the application of IAA and B. The highest N (0.70%), Ca (0.69%), Mg (0.80%) in tomato fruits and highest N (0.40%), Ca (0.93%), Mg (0.90%) in tomato plants  were obtained in 60 ppm IAA along with 2.0 kg B ha-1 and the lowest was obtained in the control treatment. In tomato fruits the highest P (0.41%) was found in IAA40B2.0 treatment, while the lowest P (0.18%) was recorded in IAA0B0.0. The lowest B (4.55µgg-1) was recorded in control, while the highest B (15.72µgg-1) was found in IAA20B2.0in tomato fruits. In tomato plants the highest P (0.34%) was recorded in IAA60B1.5 and the lowest P (0.20%) was found in control. The lowest B (4.15µgg-1) was recorded in IAA0B0.0, while the highest B(13.33µgg-1) was found in IAA40B2.0 in tomato plants. The overall results suggest that treatment IAA60B2.0 was the best from other treatments.
Occurrence of Bacterial Leaf Blight of Cocoyam and Characterisation of the Causal Organism in Northern Nigeria
Authors: Abdullahi A. , Alao S. E. L. , Banwo O. O. , Alabi O. , Lu S. , Bandyopadhyay R.
Published: March 2019

Aim: To determine the occurrence of bacterial leaf blight of cocoyam and to characterize isolates of the causal organism in Northern Nigeria.

Place and Duration of Study: The study was conducted in cocoyam farmers’ fields in Kaduna and Kano States, Department of Crop Protection, Ahmadu Bello University, Zaria, Nigeria and the Mississippi State University, USA in 2015.

Methodology: Field surveys were conducted in Kaduna and Kano States of northern Nigeria to determine occurrence of bacterial leaf blight of cocoyam. Sampling was done using quadrat. Incidence and severity of the disease was assessed on the field. Bacterial isolates obtained from the diseased samples were used for pathogenicity and hypersensitive reaction (HR) tests. Biochemical tests such as Gram, catalase, oxidase, pectolytic, amylolytic and production of acid from glycerol were carried out on the isolates. A nearly full length of the 16S rDNA gene of selected isolates was PCR amplified using 16S rRNA primers. The resulting amplicons were sequenced using Sanger sequencing. The 16S rDNA gene sequences were aligned along with other Xanthomonas sequences imported from the NCBI database using muscle tool from MEGA6.

Results: The results showed Kaduna State had higher incidence and severity (50.2%, 13.5%) than Kano State (20.5%, 5.1%) and that bacterial isolates induced blight symptoms on cocoyam and elicited HR reactions on tobacco. Isolates were Gram negative, catalase positive, oxidase negative, amylolytic, pectolytic and produced no acids from glycerol. BLAST search of sequenced genes showed 98-100% homology to Xad. Maximum likelihood phylogenetic trees constructed for the 16S rDNA gene sequences revealed isolates were identical to the Xad reference strains KP247494, KM576803 and EU203153. Generally, all the isolates obtained were Xad.

Conclusion: Bacterial leaf blight of cocoyam occurred in Kaduna and Kano States and the bacterial isolates were identical to Xanthomonas axonopodis pv. dieffenbachiae.
Economics of West African Dwarf (WAD) Goat Production among Small Holder Farmers in Humid and Tropical Region of the World
Authors: Ume S. I.
Published: March 2019

Economics of West African Dwarf (WAD) goat Production by Small Holder Farmers in humid and tropical region was studied using 120 farmers selected from southeast states of Nigeria. The information generated for the study comprised farmers’ socio-economic characteristics and other quantitative variables relevant to the study using mainly structured questionnaire and personal interviewed, descriptive Statistic such as percentage response and budgetary technique were used to address the objectives of the study. The mean of age of the farmer was 54 years, level of education was 11 years, while years of rearing experience and house hold size were 10 and 7 respectively. The result of net farm income analysis revealed that an average total cost of goat production was  $127,517 per 12 herds of goat with cost of purchasing breeding kids input resource constituting the highest (30%) of total costs of production. A positive net farm income of $23938 was realized by average goat farmer in the study area, indicating the profitability of the enterprise. The identified problems limiting goat production in the region were poor access credit, problem of pests and diseases, seasonality of forage, theft problem, poor extension contact, poor nutrition of confined animal and technology too costly. There are needs for policies options and measures to enhance farmers’ access to education, access to credit, extension services, and access to drugs at subsidized rates to ensure goat production by the farmers.
Combined Optimized SFGM(1,1,k) Model and Its Application in Total Import and Export
Authors: Yu Lang , Xiang Xiwang
Published: March 2019

Since the introduction of the fractional FGM(1,1) model, it has been widely used in all aspects of society. However, the original FGM(1,1) model has certain defects. Therefore, many experts and scholars have proposed many optimization methods for the shortcomings of the fractional FGM(1,1) model, and have been well applied. Since the gray action of the FGM(1,1) model is a fixed constant, the dynamic variation characteristics of the system cannot be well described. Based on this, this paper proposes a new SFGM(1,1,k) model by optimizing the gray action amount and reconstructing the background value of the optimized model using Simpson formula to improve the FGM(1,1) model. Then, apply it to the numerical examples of import and export totals. The results show that the combined optimization of SFGM(1,1,k) has higher fitting accuracy and better prediction effect. The validity and practicability of the SFGM(1,1,k) model are verified. The application range of FGM(1,1) model is extended.
Forage Performance of Corn Hybrids and Their Varieties
Authors: Silva Moisés T. da , Ferreira Paulo V. , Lira Rosa C. , Filho Gilson M. , Neto João V. S. , Santos Douglas F. dos , Alves Nathanyel E. , Filho Amauri M. S. , Santos Jonathan T. , Lira José E. de , Lira Maria E. Santos
Published: March 2019

The present study had as objective to evaluate the performance of maize hybrids and yours varieties for forage production in the climate and soil conditions of the forest area in the state of Alagoas. In conducting the experiment it was adopted the randomized block design, with 12 treatments (maize genotypes) and three replicates, totaling 36 experimental plot. Each experimental plot consisted of four rows of 5 meters in length, two lateral queues were discarded due to the border effect. For planting, the spacing of 0,7 m x 0,143 m was used, totalizing a final stand of 100,000 plants per hectare after thinning. At 93 days after sowing, the evaluations were carried out regarding the plants biometrics, and forage yield. Considering the conditions under which the experiment was developed, it can be concluded that: (a) The genotypes Jabotão, Branca, Branquinha and their experimental hybrids showed the highest plant height; (b) The experimental hybrid Janor presented the best culm/ear; (c) The Jabra and Branquinha genotypes are the best performance for forage yield (d) The Jabra experimental hybrid showed excellent forage aptitude, which makes it a promising material, which can be evaluated in other regions in the future and later launched as a genotype for fodder production.
Associations between Job Characteristics, Mental Health and Driving: A Secondary Analysis
Authors: Bowen Louise , Smith Andrew P.
Published: March 2019

Background: Human factors are widely acknowledged as major contributors in road traffic collision (RTC) involvement. The aim of the present study, using secondary data analysis was to analyse associations between job characteristics, mental health, personality, fatigue and driving behaviour and their potential connection to RTCs, as well as their potential links with some of the risk factors as outcome variables (driving behaviour, driver fatigue and risk-taking).

Methodology: This study used a cross-sectional approach, with 2856 clients of an insurance company completing an online survey in which they were asked about their driving and a range of other factors, such as personality, job characteristics and mental health.

Results: The results revealed that whereas the extant literature points to personality traits as directly causal of RTCs, they actually impact driving behaviour and risk-taking behaviour. In addition, an association was found between higher salary and risk-taking (the latter predictive of RTC involvement). Using the Demands, Resources and Individual Effects model (DRIVE) it was possible to examine associations between particular job characteristics and driving behaviour, driver fatigue, and risk-taking. Associations between poor levels of driving behaviour and high levels of decision making, perceived job stress, long working hours and issues of work-life balance were uncovered. Moreover, a combined effects approach revealed a 16.73-fold increase in driver fatigue for younger, single drivers who often drive in heavy traffic, on the motorway and in adverse weather, with stressful, noisy, pressurised jobs, lower in levels of respect (typical of the blue-collar worker).

Conclusion: Based on the current findings, further longitudinal research is recommended to assess causality.
Carbon Nanotubes, Directly Grown on Supporting Surfaces, Improve Neuronal Activity in Hippocampal Neuronal Networks
Authors: Rago Ilaria , Rauti Rossana , Bevilacqua Manuela , Calaresu Ivo , Pozzato Alessandro , Cibinel Matteo , Dalmiglio Matteo , Tavagnacco Claudio , Goldoni Andrea , Scaini Denis
Published: March 2019

Carbon nanotube (CNT)–modified surfaces unequivocally demonstrate their biocompatibility and ability to boost the electrical activity of neuronal cells cultured on them. Reasons for this effect are still under debate. However, the intimate contact at the membrane level between these thready nanostructures and cells, in combination with their unique electrical properties, seems to play an important role. The entire existing literature exploiting the effect of CNTs on modulating cellular behavior deals with cell cultures grown on purified multiwalled carbon nanotubes (MWNTs) deposited on a supporting surface via drop‐casting or mechanical entrapment. Here, for the first time, it is demonstrated that CNTs directly grown on a supporting silicon surface by a chemical vapor deposition (CVD)–assisted technique have the same effect. It is shown that primary neuronal cells developed above a carpet of CVD CNTs form a healthy and functional network. The resulting neuronal network shows increased electrical activity when compared to a similar network developed on a control glass surface. The low cost and high versatility of the here presented CVD‐based synthesis process, together with the possibility to create on supporting substrate patterns of any arbitrary shape of CNTs, open up new opportunities for brain–machine interfaces or neuroprosthetic devices.
Enhancing the Effect of Pharmacological Ascorbate in Cancer Therapy via Acid‐Triggered Ferritin Nanoparticles
Authors: Xu Nuo , Yang Yuan‐Fan , Chen Long , Xu Liang , Xu Xiao‐Jie , Lin Jian
Published: March 2019

The application of ascorbate (vitamin C) for cancer therapy was first proposed in the 1970s and has shown promising results in recent clinical trials. Pharmacological doses of ascorbate selectively induce cell death in different types of cancer cells through the generation of H2O2. However, some cancer cells are resistant to ascorbate. So increasing the sensitivity of resistant cancer cells to ascorbate has attracted considerable attention. Till now, a few attempts in nanomaterials have been made to improve the effect of ascorbate. In this study, a simple ferritin caged copper nanoparticle (Fn‐Cu) significantly improves the susceptibility of ascorbate‐resistant cancer cells to pharmacological ascorbate via selective inhibition of catalase activity in cancer cells, while having negligible cytotoxicity to normal cells. Remarkably, combination of Fn‐Cu with a lower dose of ascorbate significantly inhibits ascorbate‐resistant tumor growth and metastasis in vivo. These data demonstrate Fn‐Cu has the therapeutic potential by enhancing the effect of ascorbate in cancer therapy.
Graphene Heterostructure Integrated Optical Fiber Bragg Grating for Light Motion Tracking and Ultrabroadband Photodetection from 400 nm to 10.768 µm
Authors: Shivananju Bannur Nanjunda , Bao Xiaozhi , Yu Wenzhi , Yuan Jian , Mu Haoran , Sun Tian , Xue Tianyu , Zhang Yupeng , Liang Zhongzhu , Kan Ruifeng , Zhang Han , Lin Bo , Li Shaojuan , Bao Qiaoliang
Published: March 2019

Integrated photonics and optoelectronics devices based on graphene and related 2D materials are at the core of the future industrial revolution, facilitating compact and flexible nanophotonic devices. Tracking and detecting the motion of broadband light in millimeter to nanometer scale is an unfold science which has not been fully explored. In this work, tracking and detecting the motion of light (millimeter precision) is first demonstrated by integrating graphene with an optical fiber Bragg grating device (graphene‐FBG). When the incident light moves toward and away from the graphene‐FBG device, the Bragg wavelength red‐shifts and blue‐shifts, indicating its light motion tracking ability. Such light tracking capability can be further extended to an ultrabroad wavelength range as all‐optical photodetectors show the robust response from 400 nm to 10.768 µm with a linear optical response. Interestingly, it is found that graphene‐Bi2Te3 heterostructure on FBG shows 87% higher photoresponse than graphene‐FBG at both visible and telecom wavelengths, due to stronger phonon‐electron coupling and photo‐thermal conversion in the heterostructure. The device also shows superior stability even after 100 d. This work may open up amazing integrated nanophotonics applications such as astrophysics, optical communication, optical computing, optical logic gating, spectroscopy, and laser biology.
Recent Advances in Triboelectric Nanogenerator‐Based Health Monitoring
Authors: Yi Fang , Zhang Zheng , Kang Zhuo , Liao Qingliang , Zhang Yue
Published: March 2019

Health monitoring helps prevent, diagnose, and treat diseases, and has been given more and more attention in recent years. Triboelectric nanogenerators (TENGs) are promising for applications in health monitoring due to their myriad of merits including low cost, simple fabrication, light weight, self‐powered property, and wide selection of materials. Here, the recent key research achievements in TENG‐based health monitoring are comprehensively reviewed. TENGs have been applied to detect not only motion‐based health conditions such as pulse and heartbeat but also nonmotion‐based health conditions such as CO2 concentration and lactate concentration. The design of device structure, sensing mechanism, device performance, advantages and disadvantages of each kind of TENG‐based health monitors are discussed. Based on recent progresses, the existing challenges and future prospects for TENG‐based health monitoring are also discussed and summarized.
Recent Progress of the Lifetime of Organic Light‐Emitting Diodes Based on Thermally Activated Delayed Fluorescent Material
Authors: Jeon Sang Kyu , Lee Ha Lim , Yook Kyoung Soo , Lee Jun Yeob
Published: March 2019

Recently, the external quantum efficiency and lifetime of organic light‐emitting diodes (OLEDs) have been dramatically upgraded due to development of organic materials and device structure. In particular, an intramolecular or intermolecular complex based on thermally activated delayed fluorescent (TADF) materials has greatly contributed to improving OLED device performance. Although high external quantum efficiency has been the main objective of the development of TADF materials as hosts and emitters, recent interest has been directed towards the lifetime of TADF‐material‐based OLEDs. For the past several years, remarkable advances in the lifetime of phosphorescent and TADF OLEDs have been made using TADF materials as hosts or emitters in the emitting layer. Therefore, since TADF materials are useful as both hosts and emitters for a long lifetime, this work discusses the recent progress made in developing TADF materials for long‐lifetime OLEDs.
Synaptic Resistors for Concurrent Inference and Learning with High Energy Efficiency
Authors: Danesh Cameron D. , Shaffer Christopher M. , Nathan Dhruva , Shenoy Rahul , Tudor Andrew , Tadayon Macan , Lin Yvette , Chen Yong
Published: March 2019

The fastest supercomputer, Summit, has a speed comparable to the human brain, but is much less energy‐efficient (≈1010 FLOPS W−1, floating point operations per second per watt) than the brain (≈1015 FLOPS W−1). The brain processes and learns from “big data” concurrently via trillions of synapses in parallel analog mode. By contrast, computers execute algorithms on physically separated logic and memory transistors in serial digital mode, which fundamentally restrains computers from handling “big data” efficiently. The existing electronic devices can perform inference with high speeds and energy efficiencies, but they still lack the synaptic functions to facilitate concurrent convolutional inference and correlative learning efficiently like the brain. In this work, synaptic resistors are reported to emulate the analog convolutional signal processing, correlative learning, and nonvolatile memory functions of synapses. By circumventing the fundamental limitations of computers, a synaptic resistor circuit performs speech inference and learning concurrently in parallel analog mode with an energy efficiency of ≈1.6 × 1017 FLOPS W−1, which is about seven orders of magnitudes higher than that of the Summit supercomputer. Scaled‐up synstor circuits could circumvent the fundamental limitations in computers, and facilitate real‐time inference and learning from “big data” with high efficiency and speed in intelligent systems.
Dual‐Phase Single‐Ion Pathway Interfaces for Robust Lithium Metal in Working Batteries
Authors: Xu Rui , Xiao Ye , Zhang Rui , Cheng Xin‐Bing , Zhao Chen‐Zi , Zhang Xue‐Qiang , Yan Chong , Zhang Qiang , Huang Jia‐Qi
Published: March 2019

The lithium (Li) metal anode is confronted by severe interfacial issues that strongly hinder its practical deployment. The unstable interfaces directly induce unfavorable low cycling efficiency, dendritic Li deposition, and even strong safety concerns. An advanced artificial protective layer with single‐ion pathways holds great promise for enabling a spatially homogeneous ionic and electric field distribution over Li metal surface, therefore well protecting the Li metal anode during long‐term working conditions. Herein, a robust dual‐phase artificial interface is constructed, where not only the single‐ion‐conducting nature, but also high mechanical rigidity and considerable deformability can be fulfilled simultaneously by the rational integration of a garnet Al‐doped Li6.75La3Zr1.75Ta0.25O12‐based bottom layer and a lithiated Nafion top layer. The as‐constructed artificial solid electrolyte interphase is demonstrated to significantly stabilize the repeated cell charging/discharging process via regulating a facile Li‐ion transport and a compact Li plating behavior, hence contributing to a higher coulombic efficiency and a considerably enhanced cyclability of lithium metal batteries. This work highlights the significance of rational manipulation of the interfacial properties of a working Li metal anode and affords fresh insights into achieving dendrite‐free Li deposition behavior in a working battery.
Phase‐Change Hyperbolic Heterostructures for Nanopolaritonics: A Case Study of hBN/VO2
Authors: Dai Siyuan , Zhang Jiawei , Ma Qiong , Kittiwatanakul Salinporn , McLeod Alex , Chen Xinzhong , Corder Stephanie Gilbert , Watanabe Kenji , Taniguchi Takashi , Lu Jiwei , Dai Qing , Jarillo‐Herrero Pablo , Liu Mengkun , Basov D. N.
Published: March 2019

Unlike conventional plasmonic media, polaritonic van der Waals (vdW) materials hold promise for active control of light–matter interactions. The dispersion relations of elementary excitations such as phonons and plasmons can be tuned in layered vdW systems via stacking using functional substrates. In this work, infrared nanoimaging and nanospectroscopy of hyperbolic phonon polaritons are demonstrated in a novel vdW heterostructure combining hexagonal boron nitride (hBN) and vanadium dioxide (VO2). It is observed that the insulator‐to‐metal transition in VO2 has a profound impact on the polaritons in the proximal hBN layer. In effect, the real‐space propagation of hyperbolic polaritons and their spectroscopic resonances can be actively controlled by temperature. This tunability originates from the effective change in local dielectric properties of the VO2 sublayer in the course of the temperature‐tuned insulator‐to‐metal phase transition. The high susceptibility of polaritons to electronic phase transitions opens new possibilities for applications of vdW materials in combination with strongly correlated quantum materials.
Expandable Immunotherapeutic Nanoplatforms Engineered from Cytomembranes of Hybrid Cells Derived from Cancer and Dendritic Cells
Authors: Liu Wen‐Long , Zou Mei‐Zhen , Liu Tao , Zeng Jin‐Yue , Li Xue , Yu Wu‐Yang , Li Chu‐Xin , Ye Jing‐Jie , Song Wen , Feng Jun , Zhang Xian‐Zheng
Published: March 2019

Using the cytomembranes (FMs) of hybrid cells acquired from the fusion of cancer and dendritic cells (DCs), this study offers a biologically derived platform for the combination of immunotherapy and traditional oncotherapy approaches. Due to the immunoactivation implicated in the cellular fusion, FMs can effectively express whole cancer antigens and immunological co‐stimulatory molecules for robust immunotherapy. FMs share the tumor's self‐targeting character with the parent cancer cells. In bilateral tumor‐bearing mouse models, the FM‐coated nanophotosensitizer causes durable immunoresponse to inhibit the rebound of primary tumors post‐nanophotosensitizer‐induced photodynamic therapy (PDT). The FM‐induced immunotherapy displays ultrahigh antitumor effects even comparable to that of PDT. On the other hand, PDT toward primary tumors enhances the immunotherapy‐caused regression of the irradiation‐free distant tumors. Consequently, both the primary and the distant tumors are almost completely eliminated. This tumor‐specific immunotherapy‐based nanoplatform is potentially expandable to multiple tumor types and readily equipped with diverse functions owing to the flexible nanoparticle options.
Uniform Distribution of Alloying/Dealloying Stress for High Structural Stability of an Al Anode in High‐Areal‐Density Lithium‐Ion Batteries
Authors: Zhang Miao , Xiang Lei , Galluzzi Massimiliano , Jiang Chunlei , Zhang Shanqing , Li Jiangyu , Tang Yongbing
Published: March 2019

Aluminum (Al) is one of the most attractive anode materials for lithium‐ion batteries (LIBs) due to its high theoretical specific capacity, excellent conductivity, abundance, and especially low cost. However, the large volume expansion, originating from the uneven alloying/dealloying reactions in the charge/discharge process, causes structural stress and electrode pulverization, which has long hindered its practical application, especially when assembled with a high‐areal‐density cathode. Here, an inactive (Cu) and active (Al) co‐deposition strategy is reported to homogeneously distribute the alloying sites and disperse the stress of volume expansion, which is beneficial to obtain the structural stability of the Al anode. Owing to the homogeneous reaction and uniform distribution of stress during the charge/discharge process, the assembled full battery (LiFePO4 cathode with a high areal density of ≈7.4 mg cm−2) with the Cu–Al@Al anode, achieves a high capacity retention of ≈88% over 200 cycles, suggesting the feasibility of the interfacial design to optimize the structural stability of alloying metal anodes for high‐performance LIBs.
Nanoprinted Quantum Dot–Graphene Photodetectors
Authors: Grotevent Matthias J. , Hail Claudio U. , Yakunin Sergii , Dirin Dmitry N. , Thodkar Kishan , Borin Barin Gabriela , Guyot‐Sionnest Philippe , Calame Michel , Poulikakos Dimos , Kovalenko Maksym V. , Shorubalko Ivan
Published: March 2019

Photodetectors utilizing graphene field‐effect transistors sensitized by colloidal quantum dots exhibit high responsivities under infrared light illumination. Precise, microscopic spatial control over quantum dot deposition is required to gain deeper insight into device mechanisms, optimize device performance, and enable new device architectures and applications. The latter may eventually include photodetectors with subwavelength device dimensions. Here, infrared photodetectors are fabricated by electrohydrodynamic nanoprinting of colloidal PbS quantum dots onto graphene field‐effect transistors with varying quantum dot layer thicknesses on a single substrate, demonstrating the potential of the method for realizing small footprint detectors with high spatial resolution. Remarkably, while the responsivity of the photodetectors increases with increasing layer thicknesses up to 130 nm, the noise current is found to be independent of the layer thickness. In addition, the responsivity and noise current are both linearly dependent on the applied drain voltage and drain current. As a result, the specific detectivity is independent of the drain voltage, and the detector can be operated at lower drain voltages thus reducing power consumption. Finally, specific detectivities of at least 109 Jones at 1200 nm are obtained, without degradation of the charge carrier mobilities in graphene from the electrohydrodynamic printing.
Isomeric Bright Sky‐Blue TADF Emitters Based on Bisacridine Decorated DBNA: Impact of Donor Locations on Luminescent and Electroluminescent Properties
Authors: Meng Guoyun , Chen Xing , Wang Xiang , Wang Nan , Peng Tai , Wang Suning
Published: March 2019

Three isomeric boron‐containing thermally activated delayed fluorescent (TADF) emitters, namely m‐AC‐DBNA, p‐AC‐DBNA, and m′‐AC‐DBNA, are constructed by incorporating an electron‐donor acridine (AC) moiety into meta‐, para‐, or meta′‐positions of an electron‐accepting boron‐embedded rigid framework. The substitutional positions are found to dramatically affect thermal, photophysical, and electroluminescent (EL) properties. The experimental results show that the para‐substituted compound (p‐AC‐DBNA) exhibits higher decomposition temperature, higher photoluminescence (PL) quantum efficiencies, smaller singlet–triplet energy splitting, shorter delayed fluorescence lifetimes as well as a fast reverse intersystem crossing rate of over 106 s−1, compared to the meta‐isomers (m‐AC‐DBNA and m′‐AC‐DBNA). Bright and highly efficient organic light‐emitting diodes (OLEDs) with external quantum efficiencies (EQEs) up to 20.5% and 14.1% are achieved by employing p‐AC‐DBNA as doped and nondoped emitters in sky‐blue OLEDs, respectively. Moreover, excellent doping‐concentration independent EL properties and very low efficiency roll‐off at a high luminance are achieved. This isomeric strategy provides a simple method to extend structural diversity of highly efficient TADF emitters, optimize optoelectronic properties, and demonstrate the relationship of delayed fluorescence lifetime and efficiency roll‐off of the TADF devices. The three isomers also display distinct temperature‐dependent emission and mechanochromism.
Random Mutagenesis‐Driven Improvement of Carboxylate Reductase Activity using an Amino Benzamidoxime‐Mediated High‐Throughput Assay
Authors: Schwendenwein Daniel , Ressmann Anna K. , Doerr Mark , Höhne Matthias , Bornscheuer Uwe T. , Mihovilovic Marko D. , Rudroff Florian , Winkler Margit
Published: March 2019

Carboxylic acid reductases (CARs) catalyze the direct adenosine triphosphate (ATP) and nicotinamide adenine dinucleotide phosphate (NADPH) dependent reduction of carboxylic acids to their corresponding aldehydes. The identification and improvement of CARs by protein engineering is, however, severely limited by the lack of fast and generic methods to quantify aldehydes. Within this study, we applied a convenient high‐throughput assay (HTA) based on amino benzamidoxime (ABAO) that allows the substrate‐independent and chemoselective quantification of aldehydes. Random mutagenesis of the well‐known CAR from Nocardia iowensis (CARNi) to improve its activity for sterically demanding 2‐substituted benzoic acid derivatives was conducted in a KM‐dependent fashion, and the HTA applied in the presence of microbial cells. The study identified a hot spot in the active site of CARNi that increased the affinity to 2‐methoxybenzoic acid 9‐fold upon mutation from glutamine to proline (Q283P). The catalytic performance of CARNiQ283P appeared to be significantly improved also for other substrates such as 2‐substituted (2‐Cl, 2‐Br) as well as 3‐ and 4‐substituted benzoic acids (3‐OMe, 4‐OMe), and even aliphatic octanoic acid.

magnified image
Synergetic Effect of Ultrasmall Metal Clusters and Zeolites Promoting Hydrogen Generation
Authors: Sun Qiming , Wang Ning , Bai Risheng , Hui Yu , Zhang Tianjun , Do David A. , Zhang Peng , Song Lijuan , Miao Shu , Yu Jihong
Published: March 2019

Taking advantage of the synergetic effect of confined ultrasmall metal clusters and zeolite frameworks is an efficient strategy for improving the catalytic performance of metal nanocatalysts. Herein, it is demonstrated that the synergetic effect of ultrasmall ruthenium (Ru) clusters and intrinsic Brønsted acidity of zeolite frameworks can significantly promote the hydrogen generation of ammonia borane (AB) hydrolysis. Ultrasmall Ru clusters are embedded onto the silicoaluminophosphate SAPO‐34 (CHA) and various aluminosilicate zeolites (MFI, *BEA, and FAU) with tunable acidities by a facile incipient wetness impregnation method. Evidenced by high‐resolution scanning transmission electron microscopy, the sub‐nanometric Ru clusters are uniformly distributed throughout the zeolite crystals. The X‐ray absorption spectroscopy measurements reveal the existence of Ru‐H species between Ru clusters and adjacent Brønsted acid sites of zeolites, which could synergistically activate AB and water molecules, significantly enhancing the hydrogen evolution rate of AB hydrolysis. Notably, the Ru/SAPO‐34‐0.8Si (Si/Al = 0.8) and Ru/FAU (Si/Al = 30) catalysts with strong acidities afford high turnover frequency values up to 490 and 627 min−1, respectively. These values are more than a 13‐fold enhancement than that of the commercial Ru/C catalyst, and among the top level over other heterogeneous catalysts tested under similar conditions.
Alkali Chlorides for the Suppression of the Interfacial Recombination in Inverted Planar Perovskite Solar Cells
Authors: Chen Wei , Zhou Yecheng , Chen Guocong , Wu Yinghui , Tu Bao , Liu Fang‐Zhou , Huang Li , Ng Alan Man Ching , Djurišić Aleksandra B. , He Zhubing
Published: March 2019

In this work, significant suppression of the interfacial recombination by facile alkali chloride interface modification of the NiOx hole transport layer in inverted planar perovskite solar cells is achieved. Experimental and theoretical results reveal that the alkali chloride interface modification results in improved ordering of the perovskite films, which in turn reduces defect/trap density, causing reduced interfacial recombination. This leads to a significant improvement in the open‐circuit voltage from 1.07 eV for pristine NiOx to 1.15 eV for KCl‐treated NiOx, resulting in a power conversion efficiency approaching 21%. Furthermore, the suppression of the ion diffusion in the devices is observed, as evidenced by stable photoluminescence (PL) under illumination and high PL quantum efficiency with alkali chloride treatment, as opposed to the luminescence enhancement and low PL quantum efficiency observed for perovskite on pristine NiOx. The suppressed ion diffusion is also consistent with improved stability of the devices with KCl‐treated NiOx. Thus, it is demonstrated that a simple interfacial modification is an effective method to not only suppress interfacial recombination but also to suppress ion migration in the layers deposited on the modified interface due to improved interface ordering and reduced defect density.
Variation in breast milk macronutrient contents by maternal anemia and hemoglobin concentration in northern Kenya
Authors: Corbitt Mary , Paredes Ruvalcaba Nerli , Fujita Masako
Published: March 2019

Objectives

This study explored differing levels of macronutrients in breast milk in relation to maternal anemia and hemoglobin.

Methods

Archived milk specimens and data from a cross‐sectional sample of 208 breastfeeding mothers in northern Kenya, originally collected in 2006, were analyzed; data included milk fat, maternal hemoglobin concentration, and anemia status (anemia defined as hemoglobin <12 g/dL). Total protein and lactose were measured and energy was calculated. To explore the association between milk outcomes (fat, protein, lactose, and energy) and anemia, regression models were constructed with and without adjustment for maternal age, parity, and time (days) postpartum. The same models were constructed using hemoglobin as a continuous predictor in lieu of dichotomous anemia to explore the role of hemoglobin levels and anemia severity in predicting milk outcomes.

Results

The group comparison indicated significantly higher milk protein and lower milk fat for anemic mothers relative to nonanemic counterparts. After adjustment for maternal age, parity, and time postpartum, maternal anemia was associated with significantly higher milk protein (P = 0.001) and significantly lower milk fat (P = 0.025). Hemoglobin had a significant inverse relationship with milk protein (P = 0.017) and a marginally significant positive relationship with milk fat (P = 0.060) after adjusting for the maternal variables. Neither anemia nor hemoglobin was significant in predicting lactose or milk energy.

Conclusions

Maternal anemia and hemoglobin concentration may be associated with complex changes in milk macronutrients. Future research should clarify the impact of maternal anemia on a range of breast milk components while accounting for other maternal characteristics.
One‐Step Implementation of N‐Qubit Nonadiabatic Holonomic Quantum Gates with Superconducting Qubits via Inverse Hamiltonian Engineering
Authors: Kang Yi‐Hao , Chen Ye‐Hong , Shi Zhi‐Cheng , Huang Bi‐Hua , Song Jie , Xia Yan
Published: March 2019

A protocol is proposed to realize one‐step implementation of the N‐qubit nonadiabatic holonomic quantum gates with superconducting qubits. The inverse Hamiltonian engineering is applied in designing microwave pulses to drive superconducting qubits. By combining curve fitting, the wave shapes of the designed pulses can be described by simple functions, which are not hard to realize in experiments. To demonstrate the effectiveness of the protocol, a three‐qubit holonomic controlled π‐phase gate is taken as an example in numerical simulations. The results show that the protocol holds robustness against noise and decoherence. Therefore, the protocol may provide an alternative approach for implementing N‐qubit nonadiabatic holonomic quantum gates.
Doping‐Induced Amorphization, Vacancy, and Gradient Energy Band in SnS2Nanosheet Arrays for Improved Photoelectrochemical Water Splitting
Authors: Meng Linxing , Wang Siyu , Cao Fengren , Tian Wei , Long Run , Li Liang
Published: March 2019

Photoelectrochemical (PEC) water splitting is a promising strategy to convert solar energy into hydrogen fuel. However, the poor bulk charge‐separation ability and slow surface oxygen evolution reaction (OER) dynamics of photoelectrodes impede the performance. We construct In‐ and Zn/In‐doped SnS2nanosheet arrays through a hydrothermal method. The doping induces the simultaneous formation of an amorphous layer, S vacancies, and a gradient energy band. This leads to elevated carrier concentrations, an increased number of surface‐reaction sites, accelerated surface‐OER kinetics, and an enhanced bulk‐carrier separation efficiency with a decreased recombination rate. This efficient doping strategy allows to manipulate the morphology, crystallinity, and band structure of photoelectrodes for an improved PEC performance.
Direct Observation and Analysis of the Dynamics of the Photoresponsive Transcription Factor GAL4
Authors: Raghavan Guruprasad , Hidaka Kumi , Sugiyama Hiroshi , Endo Masayuki
Published: March 2019

Herein, the direct visualization of the dynamic interaction between a photoresponsive transcription factor fusion, GAL4–VVD, and DNA using high‐speed atomic force microscopy (HS‐AFM) is reported. A series of different GAL4–VVD movements, such as binding, sliding, stalling, and dissociation, was observed. Inter‐strand jumping on two double‐stranded (ds) DNAs was also observed. Detailed analysis using a long substrate DNA strand containing five GAL4‐binding sites revealed that GAL4–VVD randomly moved on the dsDNA using sliding and hopping to rapidly find specific binding sites, and then stalled to the specific sites to form a stable complex formation. These results suggest the existence of different conformations of the protein to enable sliding and stalling. This single‐molecule imaging system with nanoscale resolution provides an insight into the searching mechanism used by DNA‐binding proteins.
Technology and Family Violence in the Context of Post‐Separated Parenting
Authors: Markwick Katrina , Bickerdike Andrew , Wilson‐Evered Elisabeth , Zeleznikow John
Published: March 2019

Whilst the advent of new and increasingly accessible communication technologies undoubtedly provides new, positive, and effective ways for individuals to communicate and connect with their communities, it simultaneously provides additional means and forums for perpetrators to abuse and harass their victims. Furthermore, such technologies enable perpetrators of family violence to overcome geographical boundaries and continue their abuse post‐separation, particularly where there are children of the relationship. This paper reviews and classifies the existing literature on technology‐facilitated abuse, identifying predominant themes in relation to context and focus, as well as the gaps. New forms of criminality as well as new ways to perpetrate existing forms of criminality are described.
Effect of Dietary and Supplemental Omega‐3 Polyunsaturated Fatty Acids on Risk of Recurrent Gout Flares
Authors: Zhang MaryAnn , Zhang Yuqing , Terkeltaub Robert , Chen Clara , Neogi Tuhina
Published: March 2019

Objective

To determine the relationship between omega‐3 polyunsaturated fatty acid (n‐3 PUFA) consumption (dietary or supplemental) and risk of gout flares.

Methods

We used data from the Boston University Online Gout Study, an internet‐based case‐crossover study conducted from February 2003 to January 2012. At the times of gout flares (hazard period) and during gout flare–free periods (control periods), participants completed questionnaires regarding exposures, including supplements and diet, during the preceding 48 hours. We examined the relationship of self‐reported n‐3 PUFA–rich supplements and fish intake with the risk of recurrent gout flares using conditional logistic regression, adjusting for total purine intake, diuretic use, and other urate‐lowering or flare prophylactic medications (allopurinol, nonsteroidal antiinflammatory drugs, or colchicine).

Results

Of the 724 participants, 85% met the 1977 American College of Rheumatology preliminary criteria for the classification of the acute arthritis of primary gout. Twenty‐two percent of the participants reported some form of n‐3 PUFA consumption (supplements, 4.6%; dietary fatty fish, 19%) in the 48 hours preceding a gout flare or flare‐free period. The adjusted odds ratios were 1.01 (95% confidence interval [95% CI] 0.63–1.60; P = 0.98) for all 3 supplements combined and 0.74 (95% CI 0.54–0.99; P = 0.04) for consumption of ≥2 n‐3 PUFA–rich fish servings.

Conclusion

Dietary n‐3 PUFA–rich fish consumption, when adjusted for total purine intake, was associated with lower risk of recurrent gout flares, whereas n‐3 PUFA supplementation alone, as taken in a self‐directed manner, was not. Consumption of specific sources and adequate doses of n‐3 PUFA for gout flare prevention warrants further study in an adequately powered clinical trial.
Metal‐Based Transient Micromotors: From Principle to Environmental and Biomedical Applications
Authors: Ge Hongbin , Chen Xiao , Liu Wenjuan , Lu Xiaolong , Gu Zhongwei
Published: March 2019

Inspired by transient devices, transient self‐destroying micromotors that are propelled by metal–water/acid reactions and autonomously disappear after completing their tasks have emerged as promising tools for diverse applications. Such transient machines require careful selection of the metal matrix and well‐designed architectures for effective propulsion and customized functionality. In particular, recent advances in transient micromotors based on the active metals Zn, Fe, and Mg are introduced here. First, the fundamental design principles of transient micromotors are discussed. Then, their recent progress in environmental and biomedical applications is highlighted.
Fixed‐time state estimation for a class of switched nonlinear time‐varying systems
Authors: Dinh Thach Ngoc , Defoort Michael
Published: March 2019

This paper deals with the state estimation problem of a class of nonlinear time‐varying systems with switched dynamics. Based on the concept of fixed‐time stability, an observer is designed to reconstruct the continuous state of switched nonlinear time‐varying systems with state jumps, satisfying the minimal dwell‐time condition. Using the past input and output values of the studied system, some sufficient conditions are provided to estimate the state before the next switching. Some numerical results illustrate the effectiveness of the proposed scheme.
Modified performance of MIMO wireless networked time‐delay systems over fading channels
Authors: Zhan Heng , Cheng Ling‐Li , Zhao Zhi‐Xin , Yang Qing‐Sheng , Han Tao
Published: March 2019

In this paper, the modified performance limitation of multi‐input multi‐output (MIMO) wireless networked time‐delay systems over fading channels is investigated, where the characteristic of the fading channels is assumed to be a random process. The modified tracking performance limitation is considered based on frequency domain representation. The display expressions of performance limitation are achieved by using the co‐prime factorization and the spectral decomposition techniques. The obtained results show that the modified performance limitation of the wireless networked time‐delay systems is related to the inherent characteristics of the given plant, including the non‐minimum phase zeroes, the unstable poles, the encoding‐decoding, the fading channels, the bandwidth and the modified factor. Finally, some numerical examples are provided to demonstrate the efficiency of the proposed design method.