bluuebunny/crossref_metadata_2025 huggingface dataset:
Efficient and economical degradation of minocycline by natural bornite-activated hydrogen peroxide and persulfate: kinetics and mechanisms
Authors: Yuan Taikang , Wang Xu-dong , Zhao Xiaochen , Liu Tingting , Zhang Hongmin , Lv Yongtao , Wang Lei
Published: April 2021

Natural bornite (NBo), a sulfide mineral of copper and iron, is one of the main mineral raw materials for copper extraction. In this study, NBo-activated hydrogen peroxide (H2O2) and persulfate processes (PS) for the degradation of minocycline (MNC) in aqueous solution were systemically investigated and compared. The MNC removal rates with the NBo/PS and NBo/H2O2 processes were 86.40% and 87.50%, respectively. The mineralization rate of NBo/PS (33.96%) was higher than that of NBo/H2O2 (29.94%) after reaction for 180 min. The effects of oxidant and activator dosage, pH, common inorganic anions (i.e., Cl−, NO3−, and HCO3−), and water composition on MNC degradation were systematically evaluated. In addition, the degradation of MNC in natural water matrix and toxicity evaluation were also studied to better evaluate the feasibility of practical application of those two processes. The results of free radical quenching experiments and electron paramagnetic resonance spectroscopy (EPR) showed that HO· was the main activated species in the NBo/H2O2 system, while SO4·− and HO· were the main activated species in the NBo/PS system. The degradation of MNC in the NBo/PS system was achieved through electron transfer, while the degradation of MNC in the NBo/H2O2 system was mainly achieved through free radical addition. The degradation pathway mainly included deamidation reactions, C-C bond breakage and hydroxylation. Reusability of NBo showed that NBo was considerably stable in activating PS and H2O2 for degradation of MNC, which was cost-effective activator. This work provides a new perspective on the degradation mechanism of pollutants by Fe-Cu bimetallic sulfide activation of PS and H2O2.
A Global Review and Network Analysis of Phytophagous Insect Interactions With Ferns and Lycophytes
Authors: Fuentes-Jacques Luis Javier , Hanson-Snortum Paul , Hernández-Ortiz Vicente , Díaz-Castelazo Cecilia , Mehltreter Klaus
Published: April 2021

Ferns are the second largest lineage of vascular plants, yet our understanding of their interactions with phytophagous insects is very limited. Which insects feed on ferns? Do insects prefer specific fern taxa? Which feeding habit is the most common on ferns? Is there any evidence for coevolution between insects and ferns? Is our current knowledge on fern-insect interactions biased? To answer these questions, we analyzed 2,318 records of fern-insect interactions from 122 literature sources, based on the feeding habit of insects, fern taxa, and geographic location. We found evidence for interactions comprising 809 insect species (mainly Hemiptera, Lepidoptera, and Coleoptera) and 382 fern species (mainly Dennstaedtiaceae, Dryopteridaceae, and Pteridaceae). Leaf chewers contributed over 50% of the species, followed by sap-sucking insects (29.1%) and spore feeders (6.5%). The overall interaction analyses revealed that the entire fern-insect network had medium levels of nestedness (NODF = 43.37) and relatively low levels of specialization (H2’ = 0.24). The interaction networks of fern-feeding Coleoptera were the most specialized at family (H2’ = 0.40) and genus level (H2’ = 0.65), whereas 6 out of 10 most specialized insect families were Lepidoptera (d’ ≥ 0.44). At the genus level, all networks had a fern-biased asymmetry. Although fern-feeding generalists were common, few cases of coevolutionary radiation have been documented. We discuss the possible biases of our dataset, which also highlight gaps to perform future research, and suggest that many more phytophagous insects on ferns remain to be discovered, especially sap-sucking, gall-forming, and spore-feeding insects on modern fern groups.
Terahertz absorption characteristics of guar gum determined via microfluidic technology
Authors: Zhang Fengxuan , Wang Guoyang , Huang Haiyun , Chen Menghan , Zhang Sijia , Su Bo , Zhang Cunlin
Published: April 2021

The vibrational energy levels of many biomolecules correspond to the terahertz band; thus, terahertz technology can be used to identify these substances. Moreover, as the biological activity of most biomolecules can be observed only in aqueous solution, the characteristics of such biomolecules must be studied in aqueous solution. In this study, a simple microfluidic chip, a temperature control device and a strong electric field device were designed to study the terahertz absorption characteristics of guar gum for different temperatures, concentrations and electric field exposure durations, thus enabling the use of terahertz technology to analyse the characteristics of guar gum.
A study on the Safety of Percutaneous Tracheostomy in Patients with Severe Acute Respiratory Syndrome Novel Corona Virus 2 (SARS-nCoV2) Infection: A Single-center Observational Cohort Study in a CoVID Intensive Care Unit.
Authors: Kumar Krishna , Joshi Aditya , Nair Ranjith , Setlur Rangraj , Kapoor Rajan
Published: April 2021

Background: We studied the safety of percutaneous dilatational tracheostomy (PCDT) in severe acute respiratory syndrome novel coronavirus 2 (SARS-nCoV2). Patients & Methods: From 01 March 20 to 30 November 2020, 1635 required hospital admission of which 145 (9%) required intensive (ICU) care. The primary outcomes are mortality and secondary outcomes were duration of invasive mechanical ventilation (IMV), length of stay (LOS) in ICU and hospital, & days required for decannulation.Results: Out of the 145 (9%), 107 (73.7%) were males (mean 61.4 years, median body mass index (BMI) of 28.2 kg/m2 ), 38 (26.2%) were females (mean 58.10 years, median BMI of 31.2 kg/m2). In the cohort of 80 (55.17%) requiring IMV, 19 (23.7%) died within 72 hours and were not included in the study, 37 (group “NT”) and 24 (group “T”) had a median duration of ventilation of 9 d (IQR, 6-11) and 12 d (IQR, 11-17.25) respectively. Patients in group “T” underwent PCDT based on clinical criteria (fraction of inspired oxygen (FiO2 ) of ≤ 50% with positive end-expiratory pressure (PEEP) of ≤ 10 cms of H2O with stable hemodynamics), 16 (66.7%) had survived. The reverse transcription-polymerase chain reaction (RT-PCR) does not need to be negative, and none of the health care workers (HCW’s) were infected. The Cox-hazard ratio [HR] is 0.19, 95% Confidence interval [CI] (0.09, 0.41) with a P-value of <0.001, 83 (57.2%) were discharged with a mortality of 42.8%. Conclusions: PCDT is safe and effective in patients anticipated in need of prolonged mechanical ventilation.
Climate-driven sea level extremes compounded by marine heatwaves in coastal Indonesia
Authors: Han Weiqing , Zhang Lei , Meehl Gerald , Kido Shoichiro , Tozuka Tomoki , Li Yuanlong , McPhaden Michael , Hu Aixue , Cazenave Anny , Rosenbloom Nan , Strand Gary , West Bryan
Published: April 2021

The low-lying coastal and island regions are vulnerable to sea level rise and extreme events. Compounded by marine heatwaves, sea level extremes have devastating impacts on coastal community and marine ecosystems. As long tide gauge records are sparse, sea level extremes around Indonesia are poorly understood, and the Compound Height-Heat EXtreme (C-HHEX) events remain unexplored. Here we combine in situ and satellite observations with model simulations, to investigate the long-lasting (>1 month) sea level extremes and C-HHEXs along Indonesian coasts of the Indian Ocean since the 1960s. We find that 90% (80%) of the extreme sea level (C-HHEX) events, with a maximum monthly sea level anomaly of 0.45m, are clustered in an 8yr period of 2010-2017, due to anthropogenic global sea level rise and decadal enhancement driven by changing surface winds associated with a combined invigoration of the Indian and Pacific Walker Cells, atmospheric overturning circulations in east-west direction. Remote and local surface wind anomalies associated with negative phases of the Indian Ocean Dipole (IOD) - enhanced by La Niña – drive individual C-HHEX events under a precondition of shallow thermocline (a region of subsurface ocean with temperature decreases rapidly downward). By contrast, winds associated with monsoon and its intraseasonal oscillations force the sea level alone events under a deep thermocline condition. We conclude that the shoaling thermocline in eastern Indian Ocean under anthropogenic warming and global sea level rise favorably precondition the ocean for stronger and more frequent sea level extremes and C-HHEXs, increasing the environmental stress on Indonesia.
Does unpaid caregiving erode working hours among middle-aged Chinese adults?
Authors: Chai Huamin , Fu Rui , Coyte Peter C.
Published: April 2021

Middle-aged adults are commonly confronted with the burden of paid work and multiple caregiving roles. This paper examines the relationship between weekly hours of unpaid caregiving and hours of work using data from the baseline survey of the China Health and Retirement Longitudinal Study. The analysis was conducted on a nationally representative sample of 3,645 working-age Chinese adults aged 45-60 years who were not farming and had a young grandchild and/or a parent/parent-in-law. For women and men separately, we combined the use of a Heckman selection procedure and instrumental variables to estimate the relationship between weekly caregiving hours and hours of work. A caregiving threshold was also identified for women and men separately to allow for the testing of a kink and/or a discontinuity in this relationship. We found that for women, their working hours were initially unrelated to hours of caregiving before the threshold of 72 caregiving hours per week; then, their working hours experienced an almost two-fold increase at the caregiving threshold before falling by 2.02 percent for each additional hour of caregiving beyond the threshold. For men, their hours of work fell by 2.74 percent for each hourly increment in caregiving. Although a caregiving threshold of 112 hours was identified for men, there was insufficient evidence for a statistically significant kink or discontinuity in this relationship. These findings provide support for a range of fiscal and human resource policies that target employed family caregivers in order to advance their well-being while also maintaining their work productivity.JEL Classification: D13, J21, J22
Climate Defined but Not Soil-restricted: The Distribution of a Neotropical tree through Space and Time
Authors: Alvarez Facundo , Morandi Paulo S , Marimon-Junior Ben Hur , Exavier Reginal , Araújo Igor , Mariano Lucas H , Muller Angelica Oliveira , Feldpausch Ted R , Marimon Beatriz Schwantes
Published: April 2021

AimsBrosimum rubescens, a tree species with a Neotropical distribution, can achieve local monodominance in Southern Amazonia forests. Understanding how and why this species varies across space and time is important because the monodominance of some species alters ecosystems complexity. Here we evaluate the fundamental ecological niche of B. rubescens by species distribution models (SDM), combining predictive environmental variables with occurrence points. We specifically aim to 1) determine how the spatial distribution patterns of B. rubescens vary with different environmental predictive variables, and 2) evaluate the temporal and spatial persistence of B. rubescens in the Neotropics. MethodsTo generate the SDMs, the predictive environmental variables were incorporated as main components of climatic, hydric and soil variables. ResultsAll algorithms show higher performance in spatial predictions for hydric variables and for the combination of climatic, hydric and edaphic variables. We identified that the potential niches of B. rubescens seem to be defined by climatic fluctuations, with the edaphic conditions being predictive variables that are not restrictive of their presence on the evaluated spatial scale. From the LMG (Last Glacial Maximum) to the present, the species seems to have increased its spatial amplitude; however, from the present to the future, predictions suggest that B. rubescens will experience a considerable loss of its range. ConclusionsOur findings show the independent and combined effects of different environmental variables, allowing us to identify which limit or facilitate the spatial distribution of B. rubescens. We corroborate the spatial persistence and geographical fidelity of the species' spatial patterns over time.
The Impact of the COVID-19 Pandemic on Social Economy and Sustainability
Authors: Wei Xueli , Li Lijing , Zhang Fan
Published: April 2021

The Corona virus has been raging on across the world affecting hundreds of countries and billions of people. Naturally, it has had huge impacts on the world economy as a whole and the lives of people. This study aims to find out the effects that the COVID-19 has had on social economy and sustainability. The study takes up the primary aspects of social well-being like Poverty, Employment, The Condition of Women, Global Trade and Food Security and tries to find out the impact that the pandemic had on them. Analysing secondary data and reports from major international organisations like the United Nations and World Bank, this paper concludes that the effects of the pandemic have been huge. All the major aspects of the social economy have been affected by the pandemic and have resulted in huge losses in terms of economic well-being and social capital.
Evaluation of MQL Performances Using Various Nanofluids in Turning of AISI 304 Stainless Steel
Authors: TOUGGUI Youssef , Uysal Alper , Emiroglu Uğur , Belhadi Salim , Temmar Mustapha
Published: April 2021

In recent years, the need for eco-friendly machining processes has increased dramatically in order to limit the excessive use of conventional cutting fluids, thereby reducing their negative effects on both environment and operator’s health. In this context, dry cutting, minimum quantity lubrication (MQL) and nanofluid assisted MQL, as environmentally alternatives, have been positively shown their significance to overcome this problem. This experimental study was conducted from the perspective of performance analysis of machining characteristics in turning of AISI 304 austenitic stainless steel (ASS) under dry, MQL and nanofluids and hybrid nanofluids assisted MQL conditions with consideration of surface roughness (Ra), main cutting forces (Fc) and cutting temperature (T). In preparing the nanofluids, nano Molybdenum disulfide (MoS2), Multi-walled carbon nanotube (MWCNT) and nano graphene particles were added to the commercial vegetable cutting fluid as additives. Additionally, the effects of lubricating conditions on flank wear (VB) were investigated. In the end, statistical analysis, regression modeling and multi-criteria optimization based desirability function were performed. The results revealed that the Ra, Fc and T as well as VB were found to be lower with the use of nano graphene reinforced nanofluid assisted MQL followed by nano graphene/MoS2 reinforced hybrid nanofluid assisted MQL, MWCNT/MoS2 reinforced hybrid nanofluid assisted MQL, MWCNT reinforced nanofluid assisted MQL, nano MoS2 reinforced nanofluid assisted MQL and MQL, respectively, as compared to dry condition. Finally, it is worth mentioning that the nano graphene has the capability to perform as lubricant/coolant, thus contributing positively to the turning process.
PVP Assisted Grass-like NiSe@ZnSe Composite for Environmental Energy Applications
Authors: Vidhya M. Sangeetha , Yuvakkumar R , Ravi G. , Pannipara Mehboobali , Al-Sehemi Abdullah G. , Velauthapillai Dhayalan
Published: April 2021

Well defined NiSe@ZnSe composite electrode is synthesized along with Polyvinyl pyrrolidone (PVP) and Sodium Lauryl Sulfate (SLS) surfactant whose redox behavior is an interesting approach towards the boosting performance of the supercapacitor. The as-prepared samples were examined through standard characterization techniques. High crystallinity suggests that prepared composite NiSe@ZnSe is well appropriate for the application concerning the supercapacitor electrode material. The Raman spectroscopy identifies the functional group, vibrations, stretching of bonds and presence of defects in the samples. The surface to volume ratio of the loosely packed grass-like structures result in availability of more surface area for the electrolyte which lead to the enhanced reaction rates. As-prepared active synthesized product revealed 442 Fg-1 electrochemical capacitance at 1 Ag-1 with 99.3% high rate capability at 10 Ag-1 after 2000 cycles. Besides, notably capacity retention of the sandwiched asymmetric NiSe@ZnSe//AC device maintains 99.48% after constant charge discharge 2000 cycles displays outstanding electrochemical stability.
A homogeneous high-DAR antibody-drug conjugate platform combining THIOMABTM antibodies and XTEN polypeptides
Authors: Zacharias Neelie , Podust Vladimir , Kajihara Kimberly , leipold Douglas , Rosario Geoffrey Del , Dong Emily , Paluch Maciej , Fischer David , Zheng Kai , Lei Corinna , He Jintang , Ng Carl , Su Dian , Liu Luna , Masih Shabkhaiz , Sawyer William , Tinianow Jeff , Marik Jan , Yip Victor , Li Guangmin , Chuh Josefa , Morisaki John , Park Summer , Zheng Bing , Hernandez-Barry Hilda , Loyet Kelly , Xu Min , Kozak Katherine , Phillips Gail , Shen Ben-Quan , Wu Cong , Xu Keyang , Yu Shang-Fan , Kamath Amrita , Rowntree Rebecca , Reilly Dorothea , Pillow Thomas H. , Polson Andrew , Schellenberger Volker , Hazenbos Wouter , Sadowsky Jack
Published: April 2021

Antibody-drug conjugates (ADCs) enable cell-specific delivery of small molecules and are validated anti-cancer therapeutics. One factor limiting ADC advancement and broader application is the drug-to-antibody ratio (DAR), which dictates the number of payloads that can be delivered per antibody. With few exceptions, efficacious ADCs with DAR > 4 are inaccessible due to aggregation or rapid clearance in vivo. Here, we report a versatile platform for the generation of homogeneous ADCs with DAR up to 18, combining Cys-engineered THIOMAB antibodies and XTEN polypeptides to give “TXCs”. We show that high-DAR TXCs are stable biochemically and in vivo. We demonstrate that two different cytotoxic TXCs directed toward a tumor xenograft and one TXC targeting Staphylococcus aureus have comparable pharmacokinetics, but significantly enhanced efficacy in vivo versus conventional low-DAR ADCs. Our data suggest that high-DAR TXCs may ultimately offer several advantages versus conventional ADCs, including increased therapeutic index and efficacious delivery of less potent payloads.
Developing Horizontal Subsurface Flow Constructed Wetland using Pumice and Chrysopogon zizanioides for Tannery Wastewater Treatment
Authors: Aregu Mekonnen Birhanie
Published: April 2021

Background: High-strength wastewater defined by elevated levels of hazardous pollutants measured in BOD, heavy metals, nutrients and other toxic substances. This kind of wastewater discharged to water body without treatment from different industrial sectors that adversely affects aquatic environment and downstream water consumers. The general objective of this study is to investigate efficient substrate with selected plant type for constructed wetland to remove hazardous pollutants from tannery wastewater. This study was conducted at Modjo town from 2016 to 2018. Plug flow experimental study design was carried out. The substrate (Pumice) was collected around the study area and chemical characteristics were determined. Chrysopogon zizanioides was planted and grown for five months before running tannery wastewater for the treatment. The composite wastewater was introduced to the constructed wetland from Modjo leather industry, Ethiopia. The physicochemical analysis of the sample wastewater was done before and after treatment at four different hydraulic retention time.Results: Characterization of the untreated tannery wastewater revealed that the mean concentration of BOD5, COD, TSS, PO4-P, TP, NO3-N, TN and total chromium were 1641±373.6, 6953.33±339.4, 1868±863.1, 88.06 ±40.8, 144.53 ±20.8, 116.66 ±26.6, 650.33 ±93.6 and 18.33±6.7 mg/l respectively beyond the permissible limits. The maximum removal efficiency of the constructed wetland in pumice bed revealed that BOD5 at HRT 7and 9 days (96.42%, 96.30%), COD at HRT 5 and 7 days (96.76%, 96.91%), NO3-N at HRT 5 and 7 days (99.99%, 99.68%), TN (98.67%, 99.00%), PO4-P HRT 7and 9 days (96.97%,100%), TP at HRT 5 and 7 days (94.79%, 96.17%) and total Chromium at HRT 5 and 7 days (98.36%, 98.91%) respectively. Whereas, the removal efficiency of constructed wetland bed with gravel substrate used as a control subject with similar condition to pumice showed lower performance. The result between pumice and gravel bed was tested for their significance difference using two sample t-test statistics. Based on the test statistics, the pumice substrate perform better than the gravel significantly at 95% confidence interval, p-value = 0.01.Conclusion: Pumice substrate and Chrysopogon zizanioides have a potential ability to remove hazardous pollutants from tannery wastewater in horizontal subsurface constructed wetlands.
Phenolic Resin-coated Porous Silicon/carbon Microspheres Anode Materials for Lithium-ion Batteries
Authors: Liu Jingli , Wu Xian-ming , Chen Shang , Long Rui-lai , Yin Cai shuo , Zhang Feng
Published: April 2021

Porous silicon/carbon (Si/C) anode materials for Lithium-ion batteries was synthesized successfully by hydrochloric acid etching and calcination method using micron Si-Al alloy as silicon source and phenolic resin as carbon source. The microstructure and morphology were characterized by XRD, SEM, TEM, XPS and BET. The electrochemical performance were measured by constant current charge-discharge test and EIS. The results show that Si/C is porous structure and its pores are distributed between 1-6 nm. The specific discharge specific capacity of Si/C is 1287.0 mAh/g at a current density of 100 mA/g after 50 cycles, corresponding to the capacity retention of 91.0% (for the second cycle). Si/C delivers a high specific discharge capacity of 605.9 and 359.0 mAh/g at 1 A/g and 2 A/g, respectively. The lithium ion diffusion coefficient of Si/C is 5.98×10-11 cm2 s−1, which is higher than that of 7.57×10-12 cm2 s−1 for porous Si.
Predominance of Genetically Diverse Esbl Escherichia Coli Identified in Resistance Mapping of Largest Fresh Cum Brackish Water of Vembanad Lake, India
Authors: Vaiyapuri Murugadas , Sebastian Anna SherinPulithara , George Iris , Variem Sandhya Soolamkandath , Vasudevan Radhakrishnan Nair , George Joshy Chalil , Badireddy Madhusudana Rao , Sivam Visnuvinayagam , Peeralil Shaheer , Sanjeev Devi , Thandapani Muthulakshmi , Moses Sheela Albert , Nagarajarao Ravishankar Chandragiri , Mothadaka Mukteswar Prasad
Published: April 2021

Antimicrobial resistance (AMR) burden in Escherichia coli along the 90 km stretch of Vembanad Lake, Kerala, India was assessed. Seventy-seven percent of water samples drawn from 35 different stations of the Lake harbored E. coli. Antibiotic susceptibility test performed on 116 E. coli isolates revealed 81% were resistant to ≥ one antibiotic with 39 AMR profiles, 30% multidrug resistant, 32% extended spectrum b lactamase (ESBL) producers as per CLSI.The probability of isolating cefotaxime resistant E. coli was the highest 0.7 (P ≤ 0.05) in the Lake. Genetically diverse ESBL types blaTEM-116,blaCTX-M -152, blaCTX-M -27,blaCTX-M -55, blaCTX-M-205, and blaSHV-27 were identified. Molecular typing (ERIC PCR, MLST and PBRT) confirmed the diversity among E. coli between and within the stations. ST11439 and Single and Double Loci Variants of ST443, ST4533 were identified in Multi locus sequence typing (MLST) analysis. Inc plasmids (B/O, F, W, I1, FIIA, HI1, P-1a, K/B and N) identified in the Lake evidences the transmission potential. Low multiple antibiotic resistance index (average < 0.2) indicating lower risk to the human population albeit, an emerging concern of ESBL resistance in the Lake. The occurrence of genetically variant ESBL E. coli in Vembanad Lake signals health hazards and necessitates pragmatizing strategic control measures.
Does Beneficiaries’ Satisfaction Enhance Their Trust in State Grid for Solar PV Adoption? – An Evidence From PAPs in Rural China
Authors: Ding Liping , Shi Yin , Dai Qiyao , Zhang Zumeng , Li Jiaxin , Zhou Ling
Published: April 2021

Background: Photovoltaic Poverty Alleviation Projects (PPAPs) have been implemented in Chinese rural areas since 2014. As a new energy policy, PPAPs have played an important role in alleviating rural poverty. However, the adoption of solar PV faces multiple barriers from the perspective of beneficiaries. Therefore, this study basically aims to discuss and analyze factors affecting beneficiaries’ satisfaction and their trust in State Grid, promoting the adoption of solar PV. Methods: Based on the integrated American Customer Satisfaction Index (ACSI) and Unified Theory of Acception and Use of Technology (UTAUT) model, this study uses the Structural Equation Model (SEM) to reveal how the beneficiaries’ satisfaction enhance their trust in State Grid. The data were obtained from a survey of 928 PPAPs’ beneficiaries by stratified and random sampling in Chinese rural areas. Results: The results confirm that environmental perception in this study positively impacts on beneficiaries’ satisfaction. And perceived quality also has a positive effect on beneficiaries’ satisfaction and trust in State Grid, however, social influence has a negative impact on beneficiaries’ satisfaction; behavior expectation can directly promote beneficiaries’ satisfaction, while indirectly propel their trust in State Grid. Conclusions: This study constructs an integrated customer satisfaction model from the perspective of beneficiaries and proposes relevant measures to promote the adoption of solar PV that can be applied to poverty reduction of other developing countries worldwide.
Wet Deposition of Total Dissolved Nitrogen in Indo-Gangetic Plain (India)
Authors: Mishra Manisha , Kulshrestha Umesh Chandra
Published: April 2021

Very limited information on the magnitude and environmental impacts of both inorganic as well as organic forms of Nitrogen (N) wet deposition is available in India. Molar concentrations of inorganic (NH4+ and NO3−) and organic N in rainwater were monitored at three different land-use sites in Indo-Gangetic Plain (IGP) during the monsoon period (June-September) of 2017. It has been observed that dissolved organic N (DON) contributed significantly to the total dissolved N (TDN) ranging from 5–60%. Dissolved inorganic N (DIN = NH4+ + NO3−) concentration was recorded as high as 221.0 µmol L− 1 at urban site to as low as 65.9 µmol L− 1 at the rural site. A similar pattern was also observed for DON. NH4+ contribution to TDN had the order: urban megacity (65%) > urban (70%) > rural (75%). Agriculture and animal husbandry are the primary sources of NH4+ emissions in the rural site. However, NO3− has shown a contrasting trend at these sites (25%, 15% and 8%, respectively). Wet deposition fluxes of atmospheric TDN was observed to be higher at urban sites. This can attributed to a variety of local sources such as vehicular emission, microbial emissions, biomass burning, human excreta due to higher population density, and transportation from surrounding areas, as observed from concentration weighted trajectories (CWT) model and cluster analysis. Upwind region of IGP has experienced major influence of air mass transported from agriculturally rich northwest part of India. However, both the downwind sites have experienced by-and-large the influence of south-westerly air-masses originated over the Arabian Sea. Study has found that the DON contributes significantly to TDN and need to be included for budget assessment in South Asia.
Covid-19 Vaccination May Cause FDG Uptake Beyond Axillary Area
Authors: Fleury Vincent , Maucherat Bruno , Rusu Daniela , Dumont Frédéric , Rousseau Caroline
Published: April 2021

Background The vaccination immune response may induced false-positive 18F-FDG PET/CT uptake.Case presentationAn extended supraclavicular lymph nodal activation after Coronavirus Disease 2019 (Covid-19) vaccination revealed on 18F-FDG PET/CT mimics a Virchow nodule in a patient with medical history of well-differentiated appendicular adenocarcinoma. Conclusion This case highlights a nodal activation beyond axillary area and the importance of documenting vaccination history at the time of scanning to avoid false-positive results.
Limonin Modulated Immune and Inflammatory Responses to Suppress Colorectal Adenocarcinoma in Mice Model
Authors: Ishak Nur Iliyani Mohd , MOHAMED SUHAILA , Madzuki Iffah Nadhira , Mustapha Noordin Mohamed , Esa Norhaizan Mohd
Published: April 2021

Purpose. Inflammation and compromised immune responses often increases colorectal cancer (CRC) risk. The immune-modulating effects of limonin on carcinogen/inflammation-induced colorectal cancer (CRC) were studied in mice. Methods: Male Balb/c mice were randomly assorted into three groups (n=6): healthy control, non-treated CRC-induced (azoxymethane/dextran-sulfate-sodium AOM/DSS) control, and CRC-induced+50 mg limonin /kg body-weight. The CRC development were monitored via macroscopic, histopathological, ELISA and mRNA expression analysis. Results: Limonin downregulated inflammation (TNF-α, tumor necrosis factor-α), enhanced the adaptive immune responses (CD8, CD4, and CD19), and upregulated antioxidant defense (Nrf2, SOD2) mRNA expressions. Limonin reduced serum malondialdehyde (MDA, lipid peroxidation biomarker), prostaglandin-E2 and histopathology inflammation scores, while increasing reduced-glutathione (GSH) in the CRC-induced mice. Limonin significantly (p<0.05) increased T cells (CD4 and CD8) and B cells (CD19) in spleen tissues. The CD335 (natural killer cells) were increased in the CRC-induced mice and limonin treatment restored it to normal levels suggesting reinstatement to normal colon conditions.Conclusion: Limonin apparently mitigated CRC development, by ameliorating adaptive immune responses (CD8, CD4, and CD19), reducing inflammation (serum prostaglandin-E2; TNF-α, innate immune responses), oxidative stress and enhancing the endogenous anti-oxidation defense reactions (GSH) in the CRC-induced mice.
The impact of the timely birth-dose vaccine on the global elimination of hepatitis B
Authors: de Villiers Margaret , Nayagam Shevanthi , Hallett Timothy
Published: April 2021

Scaling-up timely hepatitis B birth-dose vaccination to 90% of new-borns in 110 low- and middle-income countries by 2030 could prevent 770,000 (600,000–1,060,000) deaths in the 2020 to 2030 birth cohorts compared to status quo, with the greatest benefits in Africa. Maintaining this could lead to elimination by 2032 in the Americas, but not before 2059 in Africa. Drops in coverage due to disruptions in 2020 may lead to 17,000 additional deaths, mostly in South-East Asia and the Western Pacific. Delays in planned scale-up could lead to an additional 630,000 deaths globally in the 2020 to 2030 birth cohorts.
Surfactant-Free Cellulose Filaments Stabilized Oil in Water Emulsions
Authors: Varamesh Amir , Prathapan Ragesh , Telmadarreie Ali , Li Jia , Gourlay Keith , Minhas Gurminder , Lu Qingye , Bryant Steven L. , Hu Jinguang
Published: April 2021

There has been significant interest over recent years in the production and application of sustainable and green materials. Among these, nanocellulose has incurred great interest because of its exceptional properties and wide range of potential applications, including in Pickering emulsions. However, the production cost of these cellulosic materials has limited their application. In this study, the capability of a new type of cheaper cellulosic material, cellulose filaments (CFs), in formulating stable oil in water Pickering emulsions was investigated and compared with three conventional nanocelluloses, namely cellulose nanocrystals (CNCs), cellulose nanofibrils (CNFs) and TEMPO-oxidized CNFs (TEMPO-CNFs). Results showed that CFs can provide stable surfactant-free emulsions over wide ranges of salt concentration (0 – 500 mM) and pH (2 – 10), as indicated by the near constant oil droplet size and dewatering index of the emulsions. This is due to the ability of CFs to strongly adsorb to the oil and water interface, as evidenced by visualizing labeled CFs with engineered carbohydrate-binding module (CBM2a) conjugated with green fluorescent protein (CBM2a-eGFP) under fluorescent microscopy. Compared to the emulsions stabilized by other types of nanocelluloses, the CFs-stabilized emulsion demonstrated a larger average droplet size and comparable (with CNFs) or better (than CNCs and TEMPO-CNFs) stability, which is partially attributed to the higher viscosity of continuous phase in the presence of CFs. The results of this study demonstrate the use of CFs as a novel and cheaper cellulosic material for stabilizing emulsions, which opens the door to a range of markets from the food industry to engineering applications.
Controlled Dispersion and Setting of Cellulose Nanofibril (CNF) - Carboxymethyl Cellulose (CMC) Pastes
Authors: Azrak Sami Miguel El Awad , Gohl Jared , Moon Robert , Schueneman Gregory , Davis Chelsea , Youngblood Jeffrey
Published: April 2021

This work investigated the redispersion and setting behavior of highly loaded (~18 wt.% solids in water) pastes of cellulose nanofibrils (CNFs) with carboxymethyl cellulose (CMC). A single-screw extruder was used to continuously process CNF+CMC pastes into cord. The adsorption of CMC onto the CNF fibrils was assessed through zeta potential and titration which revealed a surface charge change of ~61 % from -36.8 mV and 0.094 mmol/g COOH for pure CNF to -58.1 mV and 0.166 mmol/g COOH for CNF+CMC with a CMC degree of substitution of 0.9. Dried CNF with adsorbed CMC was found to be fully redispersible in water and re-extruded back into a cord without any difficulties. On the other hand, chemical treatment with hydrochloric acid, a carbodiimide crosslinker, or two wet strength enhancers (polyamide epichlorohydrin and polyamine epichlorohydrin) completely suppressed the dispersibility previously observed for dried-untreated CNF+CMC. Turbidity was used to quantify the level of redispersion or setting achieved by the untreated and chemically treated CNF+CMC in both water and a strong alkaline solution (0.1 M NaOH). Depending on the chemical treatment used, FTIR analysis revealed the presence of ester, N-acyl urea, and anhydride absorption bands which were attributed to newly formed linkages between CNF fibrils, possibly explaining the suppressed redispersion behavior. Water uptake of the differently treated and dried CNF+CMC materials agreed with both turbidity and FTIR results.
Bibliometric Analysis of Phosphogypsum Research from 1990 to 2020 Based on Literatures and Patents
Authors: Cao Yunmeng , Cui Yue , Yu Xiaokun , Li Tong , Chang I-shin , WU Jing
Published: April 2021

The demand together with the urgency of phosphogypsum (PG) treatment, will pose big challenges for many countries. This research aims to explore the research progress of PG, including basic status, cooperation situation, research fields and development trends, based on Web of Science database through bibliometric analysis of publications (articles and patents) from 1990 to 2020. The results show that the academic research of PG originated earlier, but the number of patents grew faster. China has an absolute advantage in the numbers and plays a significant role in international cooperation. The knowledge structure of PG is mainly concentrated in the fields of natural radioactivity, cement paste backfilling, soil, crystal morphology, and synthetic gas. Academic hotspots focus on the microstructure of chemical processes and various environmental impacts, and the patents hot technologies is the production of refractory materials, ceramics, surface materials, cement mortar and composite materials. The academic frontiers of PG will be the methods of recovering rare earth elements from PG, the conditions of ion solidification/stabilization in PG, the impact of reaction conditions on product quality, and the reaction mechanism at the micro-level. The frontiers of patents will focus on the improvement of manufacturing equipment, new wall materials and chemical modified polymer materials. In terms of the number of articles and patents in the future, architectural research has the maximum space for improvement. This paper conducts an in-depth analysis of PG and provides information on the technological development prospects and opportunities, which is helpful for researchers engaged in PG management.
Percolation transitions in compressed SiO2 glasses
Authors: Hasmy Anwar , Ispas Simona , Hehlen Bernard
Published: April 2021

Amorphous-amorphous transformations under pressure are generally explained by changes in the local structure from low to higher fold coordinated polyhedra [1-4].
However, as the notion of scale invariance at the critical thresholds has not been addressed, it is still unclear whether these transformations could be associated to true phase transitions.
Here we report ab initio based calculations of compressed silica (SiO2) glasses showing that the structural changes from low- to high-density amorphous structures occur through a sequence of percolation transitions.
When the pressure is increased up to 82 GPa, a series of long range ('infinite') percolating clusters built up by corner- or edge-shared tetrahedra, pentahedra, and eventually octahedra, emerge at some critical pressures and replace the previous phase of lower fold coordinated polyhedra and lower connectivity.
This mechanism provides a natural explanation for the well-known mechanical anomaly around 3 GPa as well as for the structural irreversibility beyond 10 GPa, among others.
Some of the amorphous structures that have been discovered mimic those of coesite IV and V crystals reported recently [5,6], highlighting the major role of SiO5 pentahedra-based polyamorphs in the densification process of vitreous silica.
Our observations demonstrate that the percolation theory provides a robust framework to understand the nature and the pathway of the amorphous-amorphous transformations, and open a new avenue to predict unraveled amorphous solid phases and related liquids [7,8].
Catalytic Oxidation of Toluene Over LaNixB1-xO3 (B=Co, Cu) Perovskite Catalysts
Authors: Qi Songya , Zhang Wanqi , Li Xiang , Wang Qing , Zhu Zerui , Zhou Ting , Wang Gaoxiang , Xie Aijuan , Luo Shiping
Published: April 2021

A series of LaNixB1-xO3 (B=Co, Cu) perovskite catalysts were prepared by sol-gel method and employed in toluene degradation. The catalysts were characterized by XRD, UV-Vis, SEM and XPS to investigate crystal structure, morphology and composition of the catalyst. The effect of different calcination temperatures and time on the performance of perovskite catalysts for toluene degradation were investigated. And the CO2 selectivity was also carried out on as-prepared catalysts. The results showed that a small amount of Co-doping in B site of LaNiO3 could significantly improve its toluene degradation, while the substitution of Ni with Cu could not effectively enhance its activity. When the Ni/Co molar ratio in LaNixCo1-xO3 perovskite was 3:1, LaNi0.75Co0.25O3 catalyst exhibited the best activity, and it showed relatively short time and low temperature for toluene conversion of 100%. Therefore, LaNi0.75Co0.25O3 catalyst has a broad prospect in the degradation of volatile organic pollutants.
Alleviation of Salinity and Metal Stress Using Plant Growth-Promoting Rhizobacteria Isolated From Semiarid Moroccan Copper-Mine Soils
Authors: Madline Atika , Benidire Leila , Boularbah Ali
Published: April 2021

Phytoremediation is an eco-friendly method for rehabilitation of mine tailing using plants and their associated rhizosphere microorganisms. Some heavy metal and salt-tolerant plant growth promoting rhizobacteria (PGPR) could be beneficial in alleviating soil salinity and heavy metal stress. The aim of this work is to select PGPR that could be used in phytoremediation process. Twenty-nine rhizobacteria were examined for their ability to grow at increasing concentrations of NaCl and high concentrations of Zn, Pb, Cu and Cd. The results showed that seventeen rhizobacteria displayed high salinity and metal tolerance (up to 100g L− 1 NaCl, up to 5 mM Cd, 9 mM Pb, 10 mM Zn, and Cu up to 6 mM). This work showed also that salinity and metallic stress has affected bacterial growth and metabolism by increasing intracellular proline, soluble sugars, free amino-acids and exopolysaccharides production. Moreover, almost all tested bacteria maintained their PGP traits under 10 % of NaCl and multi-metal stress. Four strains exhibiting the best PGP activities namely Mesorhizobium tamadayense, Enterobacter xiangfangensis, Pseudomonas azotifigens and Streptomyces Caelestis were selected for root elongation bioassay. The consortium of these rhizobacteria improves significantly the root elongation of Peganum harmala and Lactuca sativa under metallic and salt stress. Thus, the rhizobacteria with beneficial traits as well as tolerance to abiotic stress could be useful to stimulate plants establishment under different environmental stresses.
Genomic a Nalysis and Molecular Characteristics in Carbapenem R Esistant Klebsiella Pneumoniae Strains
Authors: Zhao Su-ying , Qiu Xingyi , Tan Yiting , Xu Ming , Xu Xiaotong , Ge Yulai , Cao Huiling , Li Min , Lin Yuxin , Zhang Zhan , Li Lei , Wu Qian
Published: April 2021

Background

Klebislla pneumoniae is an important bacterium and responsible for both infections acquired in hospital and community because of its multidrug resistance and the virulence. The aim of this research was to investigate clonal lineages, antibiotic resistance profiles and virulence factors of the hospital isolated Carbapenem Resistant strains.
Methods

Whole-genome sequencing of one strain was performed using the Illumina Hiseq and PacBio RS systems. Genomic information was comprehensively analyzed by various bioinformatics approaches. Molecular typing was based on multi locus sequence typing (MLST) and pulsed-field gel electrophoresis (PFGE) analysis. Antimicrobial susceptibility testing, drug resistance and virulence genes were determined.
Results

K. pneumoniae KPX comprised one circular chromosome and four circular plasmids. This strain harbors a variety of antimicrobial resistance and virulence determinants. The closest relative of K. pneumoniae KPX was another ST11 clinical isolate recovered Sichuan. Fifty isolates were phenotypically confirmed extended-spectrum beta-lactamases ESBLs producers. MLST analysis revealed 97% sequence type 11. Fifty Carbapenem Resistant isolates mainly belong to three clones according to the PFGE DNA patterns. PFGE patterns has more variety than ST profiles. In addition, KPC-2 (98.0%), SHV-11 (98.0%), TEM-1 (76.0%), CTX-M (76.0%), Oqxb1(66%), qnrS (70%), Int1 (42.0%), sul1 (82.0%), sul2 (96.0%), iutA (88%), iucABCD(10%), and rmpA2 (100%) genes were presented in multiple drug resistant strains.
Conclusion

The dataset presented in this study provided the genomic and epidemiological analysis of Carbapenem Resistant K. pneumoniae in hospital settings. Antimicrobial-resistance profiles suggested the presence of significant selective antibiotic pressure. Appropriate surveillance is essential to development of effective control strategies in the prevention of nosocomial infection.
Theoretical Analysis of Safety Thickness of the Water-Resistant Rock Mass of Karst Tunnel Face Taking Into Account Seepage Effect
Authors: GUO Jiaqi , Wu Wenlong , Liu Xiliang , Huang Xin , Zhu Zhengguo
Published: April 2021

This paper took into account the adverse influence of the karst water seepage effect on the water-resistant rock mass. Based on the upper-bound theorem of limit analysis and the Hoek-Brown failure criterion, through a series of formula derivation, the expression of critical safety thickness of water-resistant rock mass of karst tunnel face was finally obtained. The paper carried out a feasibility analysis, an analysis of influencing factors and a comparative analysis with previous related research achievements of this method. The results showed that: (1) With the decrease of surrounding rock grade, the safety thickness of water-resistant rock mass gradually increased, and the safety thickness of surrounding rock at all grades remained within a reasonable range. (2) The safety thickness decreased as the compressive strength, the tensile strength and parameter A increased, and it increased as the karst water pressure, the tunnel excavation height, and parameter B increased. (3) The change trend of the safety thickness with the influencing factors was completely consistent under the two conditions of considering and without the seepage effect, and the safety thickness with considering the seepage force was greater than that without considering the seepage force. Taking the Yunwushan tunnel of Yiwan railway as an example, the critical safety thickness of the water-resistant rock mass was calculated and the calculated value was in good coincidence with the safety thickness adopted in the actual project. The research results are of great significance to prevent the occurrence of high pressure filling karst geological disasters such as water inrush in tunnels.
Synthesis and Mechanism of Spherical Ag-doped Polypyrrole Assisted by Complexing Agents
Authors: Wan Chuanyun , Chen Xiaoge , Liu Xiya
Published: April 2021

Highly dispersed Ag-doped PPy spherical composites can be efficiently synthesized visa oxidative polymerization of pyrrole with FeCl3 in an aqueous Ag+-containing solution in the presence of trisodium citrate, followed by concentrated ammonia treatment. However, the formation mechanisms involved in how to control the shape and how to get the metellic Ag0 need further investigation. In order to elucidate the formation mechanisms, the intermediates in different reaction stage were collected and investigated. Combining the experimental phenomenon and the structure characterization of the samples, it was found that citrate ions make a role of complexing Ag+ to produce [Ag3(C6H5O7)n+1]3n− complexes in the early reaction stage, then mainly play a role of steric stabilizer of AgCl micelles and are responsible for the shape tailoring of PPy composite as well as the reduction of Ag+ in the process of ammonia treatment. Evidently, negative-charged AgCl micelles become the main nucleation sites of pyrrole polymerization through the electrostatic attraction between the negative and positive ions. Concentrated ammonia is adopted to eliminate AgCl cores from the precursor of Ag-doped PPy composites obtained by chemical redox reaction and provides an accelerated reaction condition for reduction of Ag+ by reductants (citrate ion or pyrrole monomer). Ag-containing micelles induction method is a facial chemical method to obtain uniform Ag-doped composites and can be broadened to design other Ag-containing functional materials.