bluuebunny/crossref_metadata_2025 huggingface dataset:
Spatio-Temporal Study of Criteria Pollutants in Nigerian City
Authors: Anyika L. C. , Alisa C. O. , Nkwoada A. U. , Opara A. I. , Ejike E. N. , Onuoha G. N.
Published: August 2020

Aims: An investigation of characteristic long term air pollutants known for temporal and spatial behaviors was conducted due to increased pollution scenarios in Nigerian cities as a result of deprived environmental enforcement of statutory obligations.

Study Design: One of the worlds’ most polluted cities (Onitsha lower basin) in Nigeria was selected for spatio-temporal study of three criteria pollutants combined with GIS and MATLAB alongside associated meteorological conditions during harmattan.

Methodology: 72-hourly analyses of the nine different locations having 4 sampling sites and 500 meters apart were done from December to February which generated over 19, 440 experimental data per quarter of each annual study.

Results: Upper Iweka/Nitel area recorded the highest concentration of SO2 pollutant at (94.2 µg/m3) due to longer residence times and low wind mixing height. Borromeo hospital showed the least active NO2 region but converges at points 1 due to North-east wind dissimilar to sampling points 1 having the lowest PM10 distribution. Measured temperature parameter correlates inversely with relative humidity and precipitation. The GIS spatial representation corresponded to temporal variability of gaseous and particulate pollutants.

Conclusion: All sampled areas had AQI above 50; hence the study identified SO2, NO2, and PM10 as Primary pollutants of Onitsha lower basin.
Agricultural Credit, A Critical Input on Farmers Income: A Study From Nayagarh District of Odisha
Authors: Rath Surya Sidhant , Mishra Rajkishore , Mohapatra Upasana
Published: August 2020

In order to protect agriculture and other allied sectors, credit is indispensable for a farmer to expand and run his business more efficiently and properly which may not otherwise be possible on his savings. In this perspective, an investigation was made to show the weightage of farm credit on the farmers’ income which was designed through a random sample survey of hundred credit availed farmers in the diverse agriculture terrains of Nayagarh block of Nayagarh district and analyzed by statistical tools like regression analysis and descriptive statistics. The statistical analysis indicated that the farm credit per household, land holding have positive and significant relationship with the household income while family size and farm expenditure are negatively related to the household income. The R2 value is 0.74 that indicated 74 per cent of the variation in dependent variable is explained by the independent variables. There is decreasing returns to scale (0.766). The average per acre farm expenses and income from sale of the crop of a sample respondent of the pooled category was Rs 15753 and Rs 31606 respectively. The farmers efficiently utilized the agricultural credit, but at the same time there should be provision for procurement of perishable goods by the government or bank agencies that would secure the income of farm borrowers. In addition, a timely and need based support in creation of quality asset will lead to the overall economic growth of the block as well as the district and ramify business of the banks.
MBA Graduates’ Perception on Job Search Sources: Evidence from Nepal
Authors: Maharjan Sumi , Devkota Niranjan , Paudel Udaya Raj , Bhandari Udbodh , Adhikari Kabita
Published: August 2020

This paper explores the graduates’ perception on job search from relevant sources. The study adopts descriptive analysis and has applied purposive sampling technique to collect data from 350 students of different MBA colleges inside the Kathmandu valley. Logit model is used for the inferential analysis of the data. The results show that the most popular recruitment sources used by employers are web sites and the internet job site. Among the respondents, 82% have applied jobs at least one time and about 55% of them use online job portal to apply job. 62% of the respondents are satisfied from the modern method due to the time saving and cost saving but same number (63%) are not satisfied by the services that provide by the job portal. The Binary Logistic regression results indicate that applying job is statistically significant with the sex, training, marital status, faced interview, interview method and company response whereas search job is significantly affected by the sex, interview method, faced interview, company response and job searching. Similarly, marital status, interview method, job categories qualification and job searching have significantly affected the saving time of graduates. The study concludes that due to the improper management of job portal and Recruitment Companies many students are facing problems in job searching process. Hence, academia should focus in soft skills required for the employment market along with their academic excellence whereas adoption of new technology by reducing the traditional technology can improve the recruitment process.
Effect of Weed Management Practices on Complex Weed Flora and Soil Microflora in Aerobic Rice under Rainfed Condition of Bihar
Authors: Kumar Birendra , Kumar Sunil , Ranjan Rakesh Deo , Azad C. S.
Published: August 2020

A Field experiment was conducted during the Kharif season of 2018 at Bihar Agricultural University, Sabour (Bihar) to evaluate the performance of different herbicides in aerobic rice (Oryza sativa L). Weed management had a positive influence on growth, yield attributes and yield of the aerobic rice. In experimental field, Cyperus rotundus, Cyperus iria, Cyperus difformis, Cynodon dactylon, Eleusine indica, Fimbristylis miliacea, Echinochloa colona, Echinochloa crus-galli, Commelina benghalensis, Caesulia auxillaris, Lippia nodiflora, Amaranthus spinosus, Oxalis acetosella, Amaranthus viridis, Eclipta alba, Phyllanthus niruri and Monochoria vaginalis were the dominant weed flora species. The results revealed that lowest weed population and weed dry weight were recorded in weed free situation which were significantly superior over rest of the herbicidal treatments. The maximum mean grain yield of aerobic rice (4.00 t/ha) was recorded by weed free which intern was statistically at par with the mean grain yield obtained from the herbicide Pyrazosulfuron fb one hand weeding (3.92 t/ha) followed by Pyrazosulfuron fb Bispyribac (3.88 t/ha), Bispyribac sodium (3.83 t/ha), Pyrazosulfuron+Ethoxysulfuron (3.62 t/ha), Bispyribac sodium+Pyrazosulfuron (3.61 t/ha) and Halosulfuron + Azimsulfuron (3.50 t/ha). Significantly lowest mean grain yield of (1.90 t/ha) was obtained from weedy check plots. The highest weed control efficiency (100%) was recorded under the treatment weed free which was followed by Pyrazosulfuron fb one hand weeding (85.96%), Pyrazosulfuron fb Bispyribac (84.77%), Bispyribac sodium (83.09%). All microflora (bacteria, fungi, actinomycetes) were recorded maximum number under the treatment weedy check. There were halosulfuron causes some phytotoxic effects at early stage on rice crop. The highest gross return (Rs.70,000/ha) was obtained by weed free which was statistically at par with Pyrazosulfuron fb one hand weeding (Rs.68,600/ha), Pyrazosulfuron fb Bispyribac(Rs.67,900/ha), Bispyribac sodium (Rs.67,025/ha), Pyrazosulfuron+Ethoxysulfuron (Rs.63,350), Bispyribac sodium+Pyrazosulfuron (Rs.58,800/ha) and significantly superior over rest of the treatments. However, the highest net return (Rs. 37,323/ha) was recorded by the treatment Pyrazosulfuron fb Bispyribac sodium which was found superior over rest of the treatments. The highest B:C ratio (Rs.2.22) was recorded by Pyrazosulfuron fb Bispyribac which was statistically at par with Bispyribac sodium (Rs.2.20), Pyrazosulfuron fb one hand weeding (Rs.2.19), Pyrazosulfuron+Ethoxysulfuron (Rs.2.13) and Bispyribac sodium+Pyrazosulfuron (Rs.1.91) all these were significantly superior over rest of the treatments.
Isolation of Bacterial Pathogens from Borehole Water Sources within the University of Port Harcourt
Authors: Stanley H. O. , Eze C. N.
Published: August 2020

A study about the bacteriological and physicochemical quality of borehole water at the University of Port Harcourt was carried out. Eight water samples was pooled from NUH Block B (Under graduate Hostel), Nelson Mandela Block B (Undergraduate Hostel), Intercontinental Hostel (Post Graduate Hostel), Donald Ekong Block C (Post graduate Hostel), Clinical Hostel, Staff quarters (Opposite Uniport Bottling plant), Dan Etete (Undergraduate Hostel) and Gambiama Staff quarters designated as Sample 1 to sample 8 respectively. Physical examination was conducted to as the sanitary and hygiene practices within the collection area. It was observed that the undergraduate hostels had the least sanitary practice. Total counts of heterotrophic bacteria count showed that the highest bacterial count was recorded from Sample 2 with bacterial count of 2.3x104 CFU/ml while the least bacterial count was recorded from sample 8 with bacterial count of 3.0x102 CFU/ml. The isolated bacterial species from the water sources were identified as Bacillus sp., Micrococcus sp., E. coli., Serratia sp., Staphylococcus sp., Enterobacter sp., Citrobacter sp. The presence of coliform bacteria in the sampled water source does not comply with the World Health Organization (WHO) standard for coliform bacteria of zero total coliform per 100 ml of water. The borehole water samples collected had pH values within 5.9-6.85 which does not comply with the WHO recommended range for drinking water standards which should fall between ≥7 to ≤9.2. Nitrate concentration as observed amongst the eight water samples was below the WHO standard of 50mg/l. The Total dissolved solutes was below 0.01 in all the tested waters samples. This study has revealed that borehole water from sampled sources within the University of Port Harcourt is not fit for human consumption without adequate treatment.
Impact of Salinity on the Germination of Two Varieties of Lycopercicum esculentum: Campell 33 and Rio Grande
Authors: Najiba Brhadda , Rabea Ziri , Najib Gmira , Adam Adey Souleymane , Kaoutar Fahad
Published: August 2020

This project aims to determine the optimal conditions for a good germination of the Rio Grande and Campbell 33 varieties of Lycopersicum esculentum. The several parameters were studied: The culture conditions, the tolerance to salinity, the total soluble aerial sugars levels, the dry matter of the aerial part and the sensitivity index.

After 12 days, seed germination in a peat-sand mixture reached 10% in the Rio Grande variety and 4.8% in the Campbell 33 variety. When the seeds germinated in vitro, the percentage reached 75% for the Rio Grande variety and 60% for the Campbell 33. In petri dishes, the percentage of germination increased to 100% for both varieties. The salinity tolerance of both varieties was also studied. Significant decreases in capacity, speed, and germination rate were observed as a result of salt stress. The greatest reductions in germination were obtained at concentrations of 400 mM NaCl and MgSO4, and 200 and 400 mM CaCl2 for the Campbell 33 variety. Total soluble aerial sugars levels increased with salt concentrations, more markedly in Rio Grande, while the evolution of dry matter of the aerial part and the root volume decreased significantly. The variation of the sensitivity index as a function of the concentrations was treated.
A HPTLC Method for Determination of Anethole in Essential Oil, Methanolic Extract of Foeniculum vulgare and Commercial Herbal Products
Authors: Alam Prawez , Alqarni Mohammad H. , Alam Pravej , Foudah Ahmed I. , Ghazwani Mohammed
Published: August 2020

A rapid and feasible method of HPTLC is standardized for quantification of anethole in essential oil’s extract and from herbal formulations of fennel seed. The developed densitometric HPTLC method was performed to estimate the existence of anethole in the essential oil, extract and herbal formulations of fennel with the optimized concentration of hexane: Ethyl acetate (8:2%, v/v, mobile phase) on glass coated silica gel 60 F254 plates (20 × 10 cm) scanned with the absorbance of λ260 nm under densitometric condition.  The Linearity of regressions revealed a satisfactory relationship between peak area and concentration of anethole in between the range of 100-600 ng/spot. This reliable method was validated as per the ICH guidelines to fulfill the necessary parameters such as accuracy and robustness. The amount of anethole in essential oil (0.098 ± 0.002%), extract (0.101 ± 0.004%) and three herbal formulations A (0.024 ± 0.004%), C (0.019 ± 0.002%) while anethole is not detected in B formulations from fennel seed was completely estimated by the developed method. The standardized methods and its validation gave new insights of HPTLC based detection and quantification of anethole in other aromatic plants as well as in other pharmacological formulations.
Potential Anticancer Effects of Aged Garlic Extract and its Water-soluble Organosulfur Compounds
Authors: Alkreathy Huda Mohammed
Published: August 2020

Background: Cancer is among the leading causes of morbidity and mortality globally; it often leads to a steep rise in healthcare expenses. It is a known fact that various dietary ingredients such as aged garlic is an active anticancer agent, and its extracts do not have a strong odor and pungent taste.

Purpose: This review summarizes the potential beneficial effects of aged garlic extract (AGE) and its water-soluble organosulfur compounds on the cancer incidences, and in the prevention and improvement of malignancy factors.

Methods: The study utilizes systematic reviews on publications of previous studies obtained from scholarly journal databases including PubMed, Medline, Ebsco Host, Google Scholar and Cochrane. The study utilizes secondary information based on the studies conducted in cancer cell lines, animal and humans as there are increasing evidence of the efficacy of AGE and AGE-derived water-soluble organosulfur compounds in cancer and other malignancies.

Conclusion and Recommendation: Although animal and laboratory results were mostly consistent, there is variable evidence from human studies. The overall findings suggest that consumption of AGE and AGE-derived organosulfur compounds can offer significant protection against cancer. In our review, we found that there are shortcomings in various studies. Therefore, we recommend that more investigations are necessary to establish whether aged garlic extract could be considered for cancer prevention.
A Study of Estimation and Analysis of Anti HBs Titre in Adolescent Children in Corrleation with Socio Demographic Profile
Authors: Jerry T. Antony Leo , Sundari S. , Ramesh Shanthi
Published: August 2020

Introduction: Viruses are the most common causative agents of hepatitis today and infect many millions of individuals annually. Viral hepatitis encompasses several diseases and represents a global health problem. It induces major morbidity and mortality and places enormous demands on economic and medical resources.

Aim of the Study: Analysis of Anti Hbs Titre in Unimmunised Adolescent Children in Correlation with Socio-Demographic Profile.

Materials and Methods: The study was conducted in the Department of Pediatrics at Sree Balaji Medical College and Hospital, Chennai from April 2017 to March 2018. Vaccinated and unvaccinated (for Hepatitis B vaccine)  adolescents between the age group of 10-19 years, who attended the department of Pediatrics, were included in this study. 160 adolescents who were vaccinated with Hepatitis B vaccine and 160 adolescents who were unvaccinated with Hepatitis B vaccine in the age group of 10-19 years. A total of 320 adolescents were included in the study. The correlation was done between two group based on socio-demographic data.

Results: Among the mothers, 10.93% (35) were illiterates, 25.62% (82) had finished primary school. 33.44% (107) and 21.56% (69) had done middle school and higher secondary school (HSS) respectively. 8.45% (27) were graduates. In the study it was found that 7.19% (23) of fathers were illiterates, 23.44% (75) had stopped with primary school and 18.43% (59) with middle school. 34.69% (111) have done HSS and 16.25% (52) were graduates. Of total adolescents who participated in 25.63% (82) were from rural areas and 74.37% (238) were from urban areas. Among participants, 49.37% (158) belong to lower and 30.63% (98) belonged to lower middle class. The middle class and the upper middle class had 9.06% (29) and 10.94% (35) respectively.

Conclusion:  The findings of the present study show the need for catch up vaccination among the adolescent's population, who missed their routine immunization with Hepatitis B vaccine. For health care professionals, this study is a evidence that stresses more about the importance of providing Hepatitis B vaccination among adolescents.
Adaptive fuzzy finite‐time fault‐tolerant control of nonlinear systems with state constraints and input quantization
Authors: Lu Changxin , Pan Yingnan , Liu Yang , Li Hongyi
Published: August 2020

This article concentrates on an adaptive finite‐time fault‐tolerant fuzzy tracking control problem for nonstrict feedback nonlinear systems with input quantization and full‐state constraints. By utilizing the fuzzy logic systems and less adjustable parameters method, the unknown nonlinear functions are addressed in each step process. In addition, a dynamic surface control technique combined with fuzzy control is introduced to tackle the variable separation problem. The problem for the effect of quantization and unlimited number of actuator faults is tackled by a damping term with smooth function in the intermediate control law. Finite‐time stability is achieved by combining barrier Lyapunov functions and backstepping method. The finite‐time controller is designed such that all the responses of the systems are semiglobal practical finite‐time stable and ensured to remain in the predefined compact sets while tracking error converges to a small neighborhood of the origin in finite time. Finally, simulation examples are utilized to testify the validity of the investigated strategy.
Disturbance observer‐based adaptive boundary iterative learning control for a rigid‐flexible manipulator with input backlash and endpoint constraint
Authors: Zhou Xingyu , Wang Haoping , Tian Yang , Zheng Gang
Published: August 2020

In this article, an observer‐based adaptive boundary iterative learning control law is developed for a class of two‐link rigid‐flexible manipulator with input backlash, the unknown external disturbance, and the endpoint constraint. To tackle the backlash nonlinearities and ensure the vibration suppression, the disturbance observers based upon the iterative learning conception are considered in the adaptive boundary control design. A barrier Lyapunov function is incorporated with boundary control law to restrict the endpoint state. Based on the defined barrier composite energy function, the tracking angle error convergence of the rigid part is guaranteed, and the vibrations of the flexible part are suppressed through the rigorous analysis. Finally, a numerical simulation is provided to illustrate the effectiveness of the proposed control.
Modulating T Cell Activation Using Depth Sensing Topographic Cues
Authors: Chaudhuri Parthiv Kant , Wang Mitchell S. , Black Charles T. , Huse Morgan , Kam Lance C.
Published: August 2020

This report examines how sensing of substrate topography can be used to modulate T cell activation, a key coordinating step in the adaptive immune response. Inspired by the native T cell–antigen presenting cell interface, micrometer scale pits with varying depth are fabricated into planar substrates. Primary CD4+ T cells extend actin‐rich protrusions into the micropits. T cell activation, reflected in secretion of cytokines interleukin‐2 and interferon gamma, is sensitive to the micropit depth. Surprisingly, arrays of micropits with 4 μm depth enhance activation compared to flat substrates but deeper micropits are less effective at increasing cell response, revealing a biphasic dependence in activation as a function of feature dimensions. Inhibition of cell contractility abrogates the enhanced activation associated with the micropits. In conclusion, this report demonstrates that the 3D, microscale topography can be used to enhance T cell activation, an ability that most directly can be used to improve production of these cells for immunotherapy.
Atomic‐Scale Control of Electronic Structure and Ferromagnetic Insulating State in Perovskite Oxide Superlattices by Long‐Range Tuning of BO6 Octahedra
Authors: Li Weiwei , Zhu Bonan , Zhu Ruixue , Wang Qiang , Lu Ping , Sun Yuanwei , Cafolla Clodomiro , Qi Zhimin , Chen Aiping , Gao Peng , Wang Haiyan , He Qing , Zhang Kelvin H. L. , MacManus‐Driscoll Judith L.
Published: August 2020

Control of BO6 octahedral rotations at the heterointerfaces of dissimilar ABO3 perovskites has emerged as a powerful route for engineering novel physical properties. However, its impact length scale is constrained at 2–6 unit cells close to the interface and the octahedral rotations relax quickly into bulk tilt angles away from interface. Here, a long‐range (up to 12 unit cells) suppression of MnO6 octahedral rotations in La0.9Ba0.1MnO3 through the formation of superlattices with SrTiO3 can be achieved. The suppressed MnO6 octahedral rotations strongly modify the magnetic and electronic properties of La0.9Ba0.1MnO3 and hence create a new ferromagnetic insulating state with enhanced Curie temperature of 235 K. The emergent properties in La0.9Ba0.1MnO3 arise from a preferential occupation of the out‐of‐plane Mn d3z2−r2 orbital and a reduced Mn eg bandwidth, induced by the suppressed octahedral rotations. The realization of long‐range tuning of BO6 octahedra via superlattices can be applicable to other strongly correlated perovskites for exploring new emergent quantum phenomena.
Controllably Engineering Mesoporous Surface and Dimensionality of SnO2 toward High‐Performance CO2 Electroreduction
Authors: Wei Facai , Wang Tingting , Jiang Xiaolin , Ai Yan , Cui Anyang , Cui Jing , Fu Jianwei , Cheng Jiangong , Lei Lecheng , Hou Yang , Liu Shaohua
Published: August 2020

Currently, the precise control of the architecture and surface of functional materials for high‐performance still remains a great challenge. Here, a feasible approach is presented to synchronously manipulate mesoporous surface and dimensionality of SnO2 catalysts into hierarchically mesoporous nanosheets and nanospheres within one simple reaction system. By adjustment of the hydrophobic chain length of different fluorinated surfactants, 0D SnO2 nanospheres with average size of 165 nm, and 2D SnO2 ulthrathin nanosheets with thickness of 22.5 nm with the distinct dimensionalities are separately obtained (one stone, two birds), both of which are well decorated with ordered mesopore arrays on their surfaces (pore size of 16 nm). The following calcination gave rise to the formation of hierarchically mesopores (5 and 16 nm, respectively) with high crystallization and improved surface area (96.8 m2 g−1). The resultant mesoporous SnO2 nanosheets as catalyst for CO2 electroreduction reaction (CO2 RR) exhibit excellent selectivity, with a high Faraday efficiency (FE) of HCOOH reaching up to 90.0% at −1.3 V and C1 FE of 97.4% at −1.2 V versus reversible hydrogen electrode, as well as long‐term stability, which is among the best performance compared to reported SnO2 materials, thanks to the collective contributions of the unique architecture and mesoporous structure.
Dimensionality Concept in Solid‐State Reactions: A Way to Control Synthesis of Functional Materials at the Nanoscale
Authors: Tokmachev Andrey M. , Averyanov Dmitry V. , Karateev Igor A. , Sokolov Ivan S. , Parfenov Oleg E. , Storchak Vyacheslav G.
Published: August 2020

The concept of dimensionality is fundamental in physics, chemistry, materials science, etc. Low‐dimensional and layered materials are distinguished by their unique physical properties and applications. Concurrently, low‐dimensional reactants, products, and reaction spaces extend the toolbox of materials science considerably. Here, the concept of dimensionality is adapted to solid‐state reactions by counting the basic axes along which the unit cell undergoes significant expansion/shrinking. For illustration, 1D synthesis of layered ternary compounds MA2X2 via derivatives of 2D‐Xenes, silicene, and germanene, is demonstrated, and the reaction mechanism and the role of templates are determined. The approach is then extended to 1D synthesis of non‐layered compounds. The 1D nature of the reactions, established with structural studies, is explored by nanoscale confinement. The mutual orientation of the reaction and confinement—parallel (thus preventing the lattice expansion) or orthogonal—controls the reaction pathways and outcome. The work provides a proof‐of‐concept for anisotropic reactivity caused by directional confinement.
A New Triclinic Phase Na2Ti3O7 Anode for Sodium‐Ion Battery
Authors: Cao Yang , Ye Qi , Wang Fanfan , Fan Xiaoliang , Hu Lintong , Wang Fakun , Zhai Tianyou , Li Huiqiao
Published: August 2020

A new phase Na2Ti3O7 compound is synthesized by solid‐state method for the first time, which is verified to belong to the triclinic structure in P‐1 space group. Compared to the conventional monoclinic Na2Ti3O7 (m‐NTO), in P21/m1 space group, the triclinic Na2Ti3O7 (t‐NTO) possesses a shorter O‐O band in the distorted TiO6 octahedron, which accounts for more smooth Na+ transport channels and a more stable layered structure with smaller fluctuation. The experimental results show that the t‐NTO keeps a low charge potential plateau at 0.3 V compared to the m‐NTO, but with much promoted structure resilience. It delivers a capacity retention of 94.7%, far exceeding the 25.7% of the m‐NTO upon decades of cycles. In situ X‐ray diffraction reveals that the conventional m‐NTO experiences an irreversible phase transition during insertion/de‐insertion of Na+, while the new t‐NTO can recover its structure reversibly after discharge and charge, which is consistent with its improved cycling performance. The results demonstrate a new t‐NTO anode and provide a new understanding for the phase diversity of sodium‐ion battery materials.
Stress Relief Principle of Micron‐Sized Anodes with Large Volume Variation for Practical High‐Energy Lithium‐Ion Batteries
Authors: Lee Yoonkwang , Lee Taeyong , Hong Jaehyung , Sung Jaekyung , Kim Namhyung , Son Yeonguk , Ma Jiyoung , Kim Sung Youb , Cho Jaephil
Published: August 2020

Practical applications of high gravimetric and volumetric capacity anodes for next‐generation lithium‐ion batteries have attracted unprecedented attentions, but still faced challenges by their severe volume changes, rendering low Coulombic efficiency and fast capacity fading. Nano and void‐engineering strategies had been extensively applied to overcome the large volume fluctuations causing the continuous irreversible reactions upon cycling, but they showed intrinsic limit in fabrication of practical electrode condition. Achieving high electrode density is particularly paramount factor in terms of the commercial feasibility, which is mainly dominated by the true density and tapping density of active material. Herein, based on finite element method calculation, micron‐sized double passivation layered Si/C design is introduced with restrictive lithiation state, which can withstand the induced stress from Li insertion upon repeated cycling. Such design takes advantage in structural integrity during long‐term cycling even at high gravimetric capacity (1400 mAh g−1). In 1 Ah pouch‐type full‐cell evaluation with high mass loading and electrode density (≈3.75 mAh cm−2 and ≈1.65 g cm−3), it demonstrates superior cycle stability without rapid capacity drop during 800 cycles.
Meeting High Stability and Efficiency in Hybrid Light‐Emitting Diodes Based on SiO2/ZrO2 Coated CsPbBr3 Perovskite Nanocrystals
Authors: Duan Yanyan , Ezquerro Cintia , Serrano Elena , Lalinde Elena , García‐Martínez Javier , Berenguer Jesús R. , Costa Rubén D.
Published: August 2020

Significant advances are realized in perovskite‐converted hybrid light‐emitting diodes (pc‐HLEDs). However, long‐living devices at high efficiencies still represent a major milestone with average stabilities of <200 h at ≈50 lm W−1 under low applied currents (<15 mA). Herein, a dual metal oxide‐coated CsPbBr3@SiO2/ZrO2 composite is prepared in a one‐pot synthesis through the kinetic control of the sol–gel reaction, followed by a gentle drying process in air. These hybrid nanoparticles show photoluminescence quantum yields of ≈65% that are stable under temperature, ambient, and irradiation stress scenarios. This is translated to pc‐HLEDs with a near‐unity conversion efficiency at any applied current, high efficiencies around 75 lm W−1, and one of the most remarkable stabilities of ≈200 and 700 h at 100 and 10 mA, respectively. In addition, the device degradation mechanism is thoughtfully rationalized comparing devices operating under ambient/inert conditions. As such, this work provides three milestones: i) a new room temperature one‐pot protocol to realize the first SiO2/ZrO2 metal oxide coating that effectively protects the emitting perovskite nanoparticle core, ii) one of the most stable and efficient pc‐HLEDs operating under ambient condition at any applied current, and iii) new insights for the degradation of pc‐HLEDs.
Antibacterial Nanopillar Array for an Implantable Intraocular Lens
Authors: Choi Goro , Song Younseong , Lim Hyungjun , Lee Song Ha , Lee Hyung Keun , Lee Eunjung , Choi Bong Gill , Lee Jae Jong , Im Sung Gap , Lee Kyoung G.
Published: August 2020

Postsurgical intraocular lens (IOL) infection caused by pathogenic bacteria can result in blindness and often requires a secondary operation to replace the contaminated lens. The incorporation of an antibacterial property onto the IOL surface can prevent bacterial infection and postoperative endophthalmitis. This study describes a polymeric nanopillar array (NPA) integrated onto an IOL, which captures and eradicates the bacteria by rupturing the bacterial membrane. This is accomplished by changing the behavior of the elastic nanopillars using bending, restoration, and antibacterial surface modification. The combination of the polymer coating and NPA dimensions can decrease the adhesivity of corneal endothelial cells and posterior capsule opacification without causing cytotoxicity. An ionic antibacterial polymer layer is introduced onto an NPA using an initiated chemical vapor deposition process. This improves bacterial membrane rupture efficiency by increasing the interactions between the bacteria and nanopillars and damages the bacterial membrane using quaternary ammonium compounds. The newly developed ionic polymer‐coated NPA exceeds 99% antibacterial efficiency against Staphylococcus aureus, which is achieved through topological and physicochemical surface modification. Thus, this paper provides a novel, efficient strategy to prevent postoperative complications related to bacteria contamination of IOL after cataract surgery.
Sustained Release of TPCA‐1 from Silk Fibroin Hydrogels Preserves Keratocyte Phenotype and Promotes Corneal Regeneration by Inhibiting Interleukin‐1β Signaling
Authors: Zhang Wei , Chen Jialin , Qu Mingli , Backman Ludvig J. , Zhang Aini , Liu Haoyang , Zhang Xiaoping , Zhou Qingjun , Danielson Patrik
Published: August 2020

Corneal injury due to ocular trauma or infection is one of the most challenging vision impairing pathologies that exists. Many studies focus on the pro‐inflammatory and pro‐angiogenic effects of interleukin‐1β (IL‐1β) on corneal wound healing. However, the effect of IL‐1β on keratocyte phenotype and corneal repair, as well as the underlying mechanisms, is not clear. This study reports, for the first time, that IL‐1β induces phenotype changes of keratocytes in vitro, by significantly down‐regulating the gene and protein expression levels of keratocyte markers (Keratocan, Lumican, Aldh3a1 and CD34). Furthermore, it is found that the NF‐κB pathway is involved in the IL‐1β‐induced changes of keratocyte phenotype, and that the selective IKKβ inhibitor TPCA‐1, which inhibits NF‐κB, can preserve keratocyte phenotype under IL‐1β simulated pathological conditions in vitro. By using a murine model of corneal injury, it is shown that sustained release of TPCA‐1 from degradable silk fibroin hydrogels accelerates corneal wound healing, improves corneal transparency, enhances the expression of keratocyte markers, and supports the regeneration of well‐organized epithelium and stroma. These findings provide insights not only into the pathophysiological mechanisms of corneal wound healing, but also into the potential development of new treatments for patients with corneal injuries.
A Moisture‐Hungry Copper Complex Harvesting Air Moisture for Potable Water and Autonomous Urban Agriculture
Authors: Yang Jiachen , Zhang Xueping , Qu Hao , Yu Zhi Gen , Zhang Yaoxin , Eey Tze Jie , Zhang Yong‐Wei , Tan Swee Ching
Published: August 2020

The earth's atmosphere houses an enormous amount of water, which could be effectively exploited for a plethora of applications. While the development of materials for harnessing this abundant resource has gained impetus in recent years, limited efforts have been devoted to in‐depth research on their agricultural applications. Herein, a novel copper(II)–ethanolamine complex (Cu‐complex), which has a maximum water uptake of up to 300% and a water production rate of 2.24 g g−1 h−1 under natural sunlight, is reported. As a proof‐of‐concept application, using this material, a fully automated and self‐sustainable solar‐powered SmartFarm device is developed. The Cu‐complex harvests atmospheric water during the night, stores the adsorbed water within, and efficiently releases the adsorbed water during the day when the device is exposed to sunlight. The water harvesting and irrigation process can be fine‐tuned to suit different types of plants and local climates for an optimal cultivation. With the SmartFarm in operation, the demand for freshwater for irrigation could be greatly reduced and urban farming techniques such as large‐scale rooftop farming could be promoted with a view of alleviating both water and food scarcity in the near future.
Effect of Adventitious Carbon on Pit Formation of Monolayer MoS2
Authors: Park Sangwook , Siahrostami Samira , Park Joonsuk , Mostaghimi Amir Hassan Bagherzadeh , Kim Taeho Roy , Vallez Lauren , Gill Thomas Mark , Park Woosung , Goodson Kenneth E. , Sinclair Robert , Zheng Xiaolin
Published: August 2020

Forming pits on molybdenum disulfide (MoS2) monolayers is desirable for (opto)electrical, catalytic, and biological applications. Thermal oxidation is a potentially scalable method to generate pits on monolayer MoS2, and pits are assumed to preferentially form around undercoordinated sites, such as sulfur vacancies. However, studies on thermal oxidation of MoS2 monolayers have not considered the effect of adventitious carbon (C) that is ubiquitous and interacts with oxygen at elevated temperatures. Herein, the effect of adventitious C on the pit formation on MoS2 monolayers during thermal oxidation is studied. The in situ environmental transmission electron microscopy measurements herein show that pit formation is preferentially initiated at the interface between adventitious C nanoparticles and MoS2, rather than only sulfur vacancies. Density functional theory (DFT) calculations reveal that the C/MoS2 interface favors the sequential adsorption of oxygen atoms with facile kinetics. These results illustrate the important role of adventitious C on pit formation on monolayer MoS2.
Calendering‐Compatible Macroporous Architecture for Silicon–Graphite Composite toward High‐Energy Lithium‐Ion Batteries
Authors: Son Yeonguk , Kim Namhyung , Lee Taeyong , Lee Yoonkwang , Ma Jiyoung , Chae Sujong , Sung Jaekyung , Cha Hyungyeon , Yoo Youngshin , Cho Jaephil
Published: August 2020

Porous strategies based on nanoengineering successfully mitigate several problems related to volume expansion of alloying anodes. However, practical application of porous alloying anodes is challenging because of limitations such as calendering incompatibility, low mass loading, and excessive usage of nonactive materials, all of which cause a lower volumetric energy density in comparison with conventional graphite anodes. In particular, during calendering, porous structures in alloying‐based composites easily collapse under high pressure, attenuating the porous characteristics. Herein, this work proposes a calendering‐compatible macroporous architecture for a Si–graphite anode to maximize the volumetric energy density. The anode is composed of an elastic outermost carbon covering, a nonfilling porous structure, and a graphite core. Owing to the lubricative properties of the elastic carbon covering, the macroporous structure coated by the brittle Si nanolayer can withstand high pressure and maintain its porous architecture during electrode calendering. Scalable methods using mechanical agitation and chemical vapor deposition are adopted. The as‐prepared composite exhibits excellent electrochemical stability of >3.6 mAh cm−2, with mitigated electrode expansion. Furthermore, full‐cell evaluation shows that the composite achieves higher energy density (932 Wh L−1) and higher specific energy (333 Wh kg−1) with stable cycling than has been reported in previous studies.
Obtaining Strong, Broadband Microwave Absorption of Polyaniline Through Data‐Driven Materials Discovery
Authors: Green Michael , Tran Anh ThiVan , Chen Xiaobo
Published: August 2020

Microwave absorbing materials (MAMs) are highly utilized in the defense and telecommunications industries, as means for reducing radar cross sections for stealth technology, and providing electromagnetic interference shielding for the information processing and transport capabilities in electronic devices. Polyaniline materials have attracted enormous attention in the field of MAM development due to their strong dielectric properties. In this manuscript, the strong dielectric action of polyaniline is utilized to demonstrate for the first time how to mathematically model the EM response of materials as a means for accurately simulating, predicting, and optimizing the microwave absorption performance. Using this process, the microwave absorbing properties of polyaniline are successfully optimized and record‐breaking performances are demonstrated for both the reflection loss and effective bandwidth, yielding experimentally‐derived responses of RL = −88.5 dB at 7.0 GHz, 3.8 mm and Δf10 = 5.5 GHz at 2.1 mm. The methods presented herein are generalizable and have the potential to be broadly applicable to MAM research and development.
Chip‐Compatible Quantum Plasmonic Launcher
Authors: Chiang Chin‐Cheng , Bogdanov Simeon I. , Makarova Oksana A. , Xu Xiaohui , Saha Soham , Shah Deesha , Martin Zachariah O. , Wang Di , Lagutchev Alexei S. , Kildishev Alexander V. , Boltasseva Alexandra , Shalaev Vladimir M.
Published: August 2020

Integrated on‐demand single‐photon sources are critical for the implementation of photonic quantum information processing systems. To enable practical quantum photonic devices, the emission rates of solid‐state quantum emitters need to be substantially enhanced and the emitted signal must be directly coupled to an on‐chip circuitry. The photon emission rate speed‐up is best achieved via coupling to plasmonic antennas, while on‐chip integration can be realized by directly coupling emitters to photonic waveguides. The realization of practical devices requires that both the emission speed‐up and efficient out‐coupling are achieved in a single architecture. Here, a novel architecture is proposed that combines chip compatibility with high radiative emission rates—a quantum plasmonic launcher. The proposed launchers contain single nitrogen‐vacancy (NV) centers in nanodiamonds as quantum emitters that offer record‐high average fluorescence lifetime shortening factors of about 7000 times. Nanodiamonds with single NVs are sandwiched between two silver films that couple more than half of the emission into in‐plane propagating surface plasmon polaritons. This simple, compact, and scalable architecture represents a crucial step toward the practical realization of high‐speed on‐chip quantum networks.
Synthesis of Functional Chemicals from Lignin‐derived Monomers by Selective Organic Transformations
Authors: Natte Kishore , Narani Anand , Goyal Vishakha , Sarki Naina , Jagadeesh Rajenahally V.
Published: August 2020

The valorization of lignin and its model compounds represents a key technology applied for the production of lignin‐monomers, which constitute as renewable feedstocks and intermediates for the synthesis of value‐added chemicals and fuels as well as molecules related to life science applications. Hence, in addition to lignin‐depolymerization, the effective utilization of lignin‐derived feedstocks such as phenols, ethers, alcohols, ketones and aldehydes is also gaining significant importance. In this regard, number of methodologies has been developed on the utility of these feedstocks for the production of various functional chemicals. In this review, we summarize the valorization of lignin‐derived feedstocks by amination, hydrogenation, dehydrogenation oxidation, carbonylation, and trifluoromethylation, hydrolysis reactions for the synthesis of amines, cyclohexanes, cyclohexanols, cyclohexanones, esters, ketones, cyclic ethers, trifluoromethylated compounds and heterocycles as well as pharmaceuticals and biomolecules.

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Oxidative Sulfonylation of Multiple Carbon‐Carbon bonds with Sulfonyl Hydrazides, Sulfinic Acids and their Salts
Authors: Mulina Olga M. , Ilovaisky Alexey I. , Parshin Vadim D. , Terent'ev Alexander O.
Published: August 2020

Oxidative coupling methodology is widely applied for the formation of carbon‐carbon and carbon‐heteroatom bonds. This review focuses on methods for oxidative sulfonylation of multiple bonds involving sulfonyl hydrazides, sulfinic acids and their salts as sulfonylation reagents. Under oxidative conditions, they generate sulfonyl radicals, trapped by multiple carbon‐carbon bonds resulting in a variety of SO2‐containing products: mainly, vinyl and alkynyl sulfones, hydroxy‐, keto, and halo‐substituted sulfones, sulfonylated derivatives of carbo‐ and heterocycles. This exhaustive review summarizes 321 references from 1996 to 2020 with the specialization of the studies of the last five years, and is divided into the chapters according to the classes of compounds being sulfonylated.

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Zika Virus Infection Leads to Variable Defects in Multiple Neurological Functions and Behaviors in Mice and Children
Authors: Zhao Ziqi , Shang Ziwei , Vasconcelos Zilton , Li Chunfeng , Jiang Yisheng , Zu Shulong , Zhang Jingyi , Wang Fengchao , Yao Li , Jung Jae U. , Brasil Patricia , Moreira Maria Elisabeth , Qin Cheng‐Feng , Kerin Tara , Nielsen‐Saines Karin , Cheng Genhong , Zhang Xiaohui , Xu Zhiheng
Published: August 2020

Zika virus (ZIKV) has evolved into a global health threat because of its causal link to congenital Zika syndrome. ZIKV infection of pregnant women may cause a spectrum of abnormalities in children. In the studies in Brazil, a large cohort of children with perinatal exposure to ZIKV is followed, and a spectrum of neurodevelopmental abnormalities is identified. In parallel, it is demonstrated that infection of the mouse neonatal brain by a contemporary ZIKV strain instead of an Asian ancestral strain can cause microcephaly and various abnormal neurological functions. These include defects in social interaction and depression, impaired learning and memory, in addition to severe motor defects, which are present in adult mice as well as in the prospective cohort of children. Importantly, although mouse brains infected later after birth do not have apparent abnormal brain structure, those mice still show significant impairments of visual cortical functions, circuit organization, and experience‐dependent plasticity. Thus, the study suggests that special attention should be paid to all children born to ZIKV infected mothers for screening of abnormal behaviors and sensory function during childhood.
Mucosal Vaccination for Influenza Protection Enhanced by Catalytic Immune‐Adjuvant
Authors: Qin Tao , Ma Shang , Miao Xinyu , Tang Yan , Huangfu Dandan , Wang Jinyuan , Jiang Jing , Xu Nuo , Yin Yuncong , Chen Sujuan , Liu Xiufan , Yin Yinyan , Peng Daxin , Gao Lizeng
Published: August 2020

Influenza poses a severe threat to global health. Despite the whole inactivated virus (WIV)‐based nasal vaccine being a promising strategy for influenza protection, the mucosal barrier is still a bottleneck of the nasal vaccine. Here, a catalytic mucosal adjuvant strategy for an influenza WIV nasal vaccine based on chitosan (CS) functionalized iron oxide nanozyme (IONzyme) is developed. The results reveal that CS‐IONzyme increases antigen adhesion to nasal mucosa by 30‐fold compared to H1N1 WIV alone. Next, CS‐IONzyme facilitates H1N1 WIV to enhance CCL20‐driven submucosal dendritic cell (DC) recruitment and transepithelial dendrite(TED) formation for viral uptake via the toll‐like receptor(TLR) 2/4‐dependent pathway. Moreover, IONzyme with enhanced peroxidase (POD)‐like activity by CS modification catalyzes a reactive oxygen species (ROS)‐dependent DC maturation, which further enhances the migration of H1N1 WIV‐loaded DCs into the draining lymph nodes for antigen presentation. Finally, CS‐IONzyme‐based nasal vaccine triggers an 8.9‐fold increase of IgA‐mucosal adaptive immunity in mice, which provides a 100% protection against influenza, while only a 30% protection by H1N1 WIV alone. This work provides an antiviral alternative for designing nasal vaccines based on IONzyme to combat influenza infection.
Large‐Grained Perovskite Films Enabled by One‐Step Meniscus‐Assisted Solution Printing of Cross‐Aligned Conductive Nanowires for Biodegradable Flexible Solar Cells
Authors: Qi Jiabin , Chen Shuo , Lan Chuntao , Wang Aurelia Chi , Cui Xun , You Zhengwei , Zhang Qinghong , Li Yaogang , Wang Zhong Lin , Wang Hongzhi , Lin Zhiqun
Published: August 2020

Increasing performance demand associated with the short lifetime of consumer electronics has triggered fast growth in electronic waste, leading to serious ecological challenges worldwide. Herein, a robust strategy for judiciously constructing flexible perovskite solar cells (PSCs) that can be conveniently biodegraded is reported. The key to this strategy is to capitalize on meniscus‐assisted solution printing (MASP) as a facile means of yielding cross‐aligned silver nanowires in one‐step, which are subsequently impregnated in a biodegradable elastomeric polyester. Intriguingly, the as‐crafted hybrid biodegradable electrode greatly constrains the solvent evaporation of the perovskite precursor solution, thereby generating fewer nuclei and in turn resulting in the deposition of a large‐grained dense perovskite film that exhibits excellent optoelectronic properties with a power conversion efficiency of 17.51% in PSCs. More importantly, the hybrid biodegradable electrode‐based devices also manifest impressive robustness against mechanical deformation and can be thoroughly biodegraded after use. These results signify the great potential of MASP for controllably assembling aligned conductive nanomaterials for biodegradable electrodes. As such, it represents an important endeavor toward environmentally friendly, multifunctional and flexible electronic, optoelectronic, photonic, and sensory materials and devices.