bluuebunny/crossref_metadata_2025 huggingface dataset:
Hyperpyrexia in patients with COVID‐19
Authors: Suwanwongse Kulachanya , Shabarek Nehad
Published: June 2020

Coronavirus disease 2019 (COVID‐19), caused by severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) is a global health emergency, in which its effective treatment and prevention remain obscured. Hyperpyrexia is an elevation of body temperature above 106.7°F (41.5°C) due to an abnormally increased hypothalamic‐thermoregulatory set. The pathophysiology, impact, and outcomes of hyperpyrexia in patients with COVID‐19 have not yet been studied. Herein, we present clinical features and outcomes of six patients with COVID‐19 who had developed hyperpyrexia during hospitalization. All patients expired shortly after the onset of hyperpyrexia. Hyperpyrexia seems to adversely impact the outcomes and mortality in patients with COVID‐19. The underlying mechanisms of developing hyperpyrexia in COVID‐19 are mysterious. We propose it may be caused by SARS‐CoV‐2‐related brain injury, exuberant immune response, and thrombus formation. More research is needed to verify our results. Understanding the association between hyperpyrexia and SARS‐CoV‐2 will help to elucidate the COVID‐19 pathogenesis, which is mandatory for developing effective treatment strategies.
Long‐range surface plasmon enhanced Raman spectroscopy at highly damping platinum electrodes
Authors: Ikegaya Soma , Motobayashi Kenta , Ikeda Katsuyoshi
Published: June 2020

Knowledge of electrode/electrolyte interfacial structures is the first step toward a better understanding of electrochemical reactions. Among several surface‐specific vibrational spectroscopy, plasmonic enhancement of Raman scattering signals is recognized as a powerful method for in situ observation of electrochemical metal/dielectric interfaces. However, the applicability of this technique is governed by the resonance behavior of surface plasmons at the interface. Although platinum group metals are one of the most interesting materials for electrocatalysis, surface plasmon polaritons are largely damped at these surfaces by their localized d‐electrons. Thus, the plasmon enhanced Raman spectroscopy is normally useless for studying such catalytic surfaces. In this work, the attenuation of surface plasmons at highly damping Pt surface is reduced using a symmetric slab mode, which is a strongly coupled surface plasmons excited at both interfaces of a thin metal film. The prolonged propagation of surface plasmons in this double‐interface configuration leads to a substantial enhancement of local fields even at lossy Pt surface. The theoretical calculation indicates that the enhancement factor of Raman scattering intensity can reach the order of 104 at Pt/solution interfaces in this coupled plasmon mode. We experimentally demonstrate that Raman scattering signals are indeed significantly enhanced at Pt surface under electrochemical conditions. This strategy provides us a novel surface‐specific spectroscopic method for the molecular‐scale investigation of electrocatalytic reactions.
3‐D microstructural changes in relation to the evolution of quality during ripening of mango (Mangifera indica L. cv. Carabao)
Authors: Cantre Dennis , Mata Clara I , Verboven Pieter , Hertog Maarten LATM , Nicolaï Bart M
Published: June 2020

BACKGROUND

The ripening of mango involves changes in texture, flavor, and color, affecting the quality of the fruit. Previous studies have investigated the physiology on the evolution of quality during ripening but only a few have looked at microstructural changes during ripening. None of them has provided an insight into the relationhip between 3‐D microstructure and the evolution of quality during ripening. As the 3‐D microstructure of fruit tissue determines its mechanical and gas‐transport properties, it is likely to affect fruit texture, respiratory metabolism, and other ripening processes.

RESULTS

The present study focuses on the role of 3‐D microstructural changes in relation to quality changes during mango ripening. Microstructural imaging using X‐ray micro‐computed tomography suggested the incidence of cell leakage, which was confirmed by the measurement of electrolyte leakage from the fruit peel. Due to cell leakage, porosity, pore connectivity, and pore local diameter were decreased whereas the tissue local diameter and pore specific area were increased. The decline in respiration and respiratory quotient during ripening followed the microstructural changes observed. Meanwhile, changes in aroma were observed such as a decrease in monoterpenes and an increase in esters and other fermentative metabolites.

CONCLUSION

Overall, the results provide a complete, integrated picture of microstructural changes during ripening accompanying the evolution of fruit quality, suggesting functional relationships between the two. © 2020 Society of Chemical Industry
Soil nitrate leaching under grazed cool‐season grass pastures of the North Central US
Authors: Jackson Randall D
Published: June 2020

Nitrate leaching from agricultural cropping systems contributes to widespread and devastating eutrophication of water bodies globally. In the North Central USA, this problem is acute, with millions of dollars spent annually in efforts to clean up recreational and drinking water. The frequent soil disturbance and exogenous nitrogen (N) amendments applied in annual cropping systems make them major sources of ground‐ and surface‐water nitrate pollution. Perennial grasslands under managed livestock grazing have been touted for their ability to retain soils and nutrients while simultaneously providing milk and meat to society. The present study provides an evaluation of the peer‐reviewed literature addressing nitrate leaching loads beneath corn, pasture and prairie in temperate humid and sub‐humid regions of the US, with a focus on cool‐season grass pastures. Inputs of exogenous N to these agroecosystems comes from wet and dry deposition, livestock manure from imported feed, biological fixation and inorganic N fertilizer. Nitrate loads were highest beneath corn and lowest beneath restored prairie and switchgrass managed for bioenergy. Cool‐season grass pastures had relatively low levels of nitrate leaching loads where little or no N was applied. However, where grazed perennial grasslands had inorganic N applied, nitrate leaching loads rivaled those of corn in some cases. When producing milk and meat from livestock, grazed perennial cool‐season grass pastures should reduce nitrate leaching loads compared to growing corn that is used to feed livestock in confinement. However, cool‐season grass pastures can lose significant nitrate to leaching with moderate‐ to high‐levels of exogenous N inputs. © 2020 Society of Chemical Industry
Comparing Exposure‐ and Coping Skills–Based Treatments on Trauma‐Related Guilt in Veterans With Co‐Occurring Alcohol Use and Posttraumatic Stress Disorders
Authors: Capone Christy , Tripp Jessica C. , Trim Ryan S. , Davis Brittany C. , Haller Moira , Norman Sonya B.
Published: June 2020

Posttraumatic stress disorder (PTSD) and substance use disorders (SUD) commonly co‐occur, and this comorbidity (PTSD–SUD) is associated with more severe symptoms and functional impairment than either disorder alone. Growing evidence indicates that trauma‐related guilt, typically concerning negative appraisals of one's actions or inaction during a traumatic event, is associated with PTSD, depression, suicidality, and, possibly, substance use. The present study examined whether integrated treatment for PTSD–SUD was effective in reducing trauma‐related guilt as measured by the Trauma‐Related Guilt Inventory. Data were drawn from a randomized clinical trial comparing the effectiveness of two integrated therapies on treatment outcomes in a sample of U.S. veterans (N = 119) with comorbid PTSD and SUD. Participants were randomized to receive either Concurrent Treatment of PTSD and Substance Use Disorders Using Prolonged Exposure (COPE; n = 63) or Seeking Safety (SS; n = 56). The results indicated that global guilt decreased over time for the whole sample. However, there was a significant Treatment × Time interaction, such that participants in the COPE condition reported lower rates of global guilt, d = 0.940, over time compared to those in the SS condition, d = .498. To our knowledge, this was the first study to examine the effects of integrated PTSD–SUD treatment on trauma‐related guilt. The findings highlight that exposure‐based, trauma‐focused treatment for comorbid PTSD–SUD can be more effective in decreasing trauma‐related guilt, with potentially longer‐lasting effects, than non–exposure‐based treatment, adding evidence that patients with PTSD–SUD should be offered such treatment.
Long‐term Outcomes for Revision Endoscopic Dacryocystorhinostomy—The Effect of the Primary Approach
Authors: Allon Raviv , Cohen Oded , Bavnik Yosef , Milstein Asher , Halperin Doron , Warman Meir
Published: June 2020

Objectives/Hypothesis

Revision endoscopic dacryocystorhinostomy (END‐DCR) is the preferred approach for failed primary surgeries, yet quality data on long‐term outcomes are lacking. This study aimed to evaluate three aspects of revision END‐DCR: 5‐year success rates, patient satisfaction, and the primary surgical approach's possible impact on revision.

Methods

This retrospective study included all revision END‐DCRs conducted at Kaplan Medical Center between the years 2002 and 2015. For long‐term follow‐up analysis, two subgroups of first and second revision END‐DCRs with a minimum of documented 5‐year follow‐up after surgery were defined. Data were analyzed according to the primary surgical approach. Surgical success was defined by either anatomical (observed patent lacrimal flow) or functional (symptoms cessation) success. Patient satisfaction was measured by a questionnaire.

Results

After exclusions, a total of 45 eyes from 38 patients who underwent revision END‐DCR surgeries were included in the study. The yearly success rates from immediate to 5 years following the first revision were 93.3%, 75.5%, 71.1%, 68.9%, 68.9%, and 68.9% for the entire cohort, respectively. Immediate and 5‐year success rates following the second revision were 88.8% and 77.8%, respectively. Primary END‐DCR showed favorable 5‐year success rates and patient satisfaction over primary external dacryocystorhinostomy (EXT‐DCR) in both first and second revisions, but this did not reach significance.

Conclusions

Revision END‐DCR carries an excellent short‐term success rate, which decreases mainly throughout the first 2 years following surgery. Postoperative follow‐up should be maintained within this timeframe. Revision END‐DCR following either primary endoscopic or EXT‐DCR produces comparable surgical outcomes and patient‐reported satisfaction.

Level of Evidence

3b Laryngoscope, 131:E682–E688, 2021
Methane emission offsets carbon dioxide uptake in a small productive lake
Authors: Vachon Dominic , Langenegger Timon , Donis Daphne , Beaubien Stan E. , McGinnis Daniel F.
Published: June 2020

Here, we investigate the importance of net CH4 production and emissions in the carbon (C) budget of a small productive lake by monitoring CH4, CO2, and O2 for two consecutive years. During the study period, the lake was mostly a net emitter of both CH4 and CO2, while showing positive net ecosystem production. The analyses suggest that during the whole study period, 32% ± 26% of C produced by net ecosystem production was ultimately converted to CH4 and emitted to the atmosphere. When converted to global warming potential, CH4 emission (in CO2 equivalents) was about 3–10 times higher than CO2 removal from in‐lake net ecosystem production over 100‐yr and 20‐yr time frames, respectively. Although more work in similar systems is needed to generalize these findings, our results provide evidence of the important greenhouse gas imbalance in human‐impacted aquatic systems.
Supercontinuum Generation in Media with Sign‐Alternated Dispersion
Authors: Zia Haider , Lüpken Niklas M. , Hellwig Tim , Fallnich Carsten , Boller Klaus‐J.
Published: June 2020

When an ultrafast optical pulse with high intensity propagates through transparent material a supercontinuum can be coherently generated by self‐phase modulation, which is essential to many photonic applications in fibers and integrated waveguides. However, the presence of dispersion causes stagnation of spectral broadening past a certain propagation length, requiring an increased input peak power for further broadening. Overcoming such spectral stagnation will be key to achieve practical integrated supercontinuum devices. Here, a concept is presented to drive supercontinuum generation with significantly lower input power by counteracting spectral stagnation via repeatedly alternating the sign of group velocity dispersion along the propagation. The effect is experimentally demonstrated in dispersion alternating fiber in excellent agreement with modeling, revealing almost an order of magnitude reduced peak power compared to uniform dispersion. Calculations also reveal a similar power reduction with integrated optical waveguides, simultaneously with a significant increase in flat bandwidth, which is important for on‐chip broadband photonics.
Enhanced Mechanical and Shape Memory Properties of Poly(propylene glycol)‐Based Star‐Shaped Polyurethane
Authors: Xu Zhaozan , Cui Yangli , Li Tingting , Dang Haichun , Li Jianfeng , Cheng Fangqin
Published: June 2020

A poly(propylene glycol)‐based star‐shaped thermoplastic shape memory polyurethane elastomer (STPU) is synthesized by bulk polymerization with the addition of trifunctional poly‐propylene glycerol (PPG‐3) to improve the mechanical and shape memory properties. The mechanical properties are enhanced significantly with the addition of PPG‐3. The tensile strength of STPU is up to 36.0 MPa, which is almost two times higher than that of linear polyurethane (18.4 MPa). The star‐shaped structure, reduction in microphase separation, and good phase compatibility of STPU are the reasons for the enhancement of mechanical properties. The branching degree of STPU (up to 1.83) is much higher than that of linear polyurethane (0.5). STPU shows higher shape memory fixity ratio (97.2%) at −10 °C and recovery ratio (96.7%) at 40 °C than TPU. Therefore, the design and synthesis of star‐shaped polyurethane is an effective approach for improving the mechanical and shape memory properties of polyurethane elastomer.
Sodium Citrate Kolbe Electrolysis Polymerization in Aqueous Solution with Controlled Molecular Weight Distribution
Authors: Liu Ting‐Ran , Hu Zhi‐Yang , Chen Jian‐Qiu , Zhao Yu‐Zeng , Ge Hong‐Hua
Published: June 2020

Controlled‐molecular‐weight‐distribution polymerization of sodium citrate in aqueous solution is successfully performed by Kolbe electrolysis reaction. It can be carried out in aqueous solution and no initiator and catalyst need to be added specially in this new polymerization procedure. The molecular weight of polymerization product linear rises with increasing conversion rate, and its distribution is maintained relatively narrowly (Mw/Mn < 1.55). The molecular weight and its distribution are obviously affected by a couple of elements, such as reaction temperature, as well as the kinds and amount of addition neutral salt ions in electrolysis solution. Kolbe electrolysis can realize the controlled‐molecular‐weight‐distribution polymerization of sodium citrate monomer effectively, which expands the scope of non‐olefin monomers used for controlled‐molecular‐weight‐distribution polymerization.
Preparation of Polyurethane‐Urea Elastomers Using Low Molecular Weight Aliphatic Diamines Enabled by Reversible CO2 Chemistry
Authors: Zhang Bo , Li Xiaoxiao , Tian Yumeng , Wang Jie , Zhao Xiaoli , Yang Xiaoniu
Published: June 2020

The use of low molecular weight (LMw) aliphatic diamines for the synthesis of polyurethane‐urea elastomers (PUUEs) is an effective method for introducing abundant, strong hydrogen bonds with the aim of improving the thermal and mechanical properties of PUUEs. However, the reaction between isocyanates and LMw aliphatic diamines is too rapid to produce PUUEs. In this study, PUUEs incorporating LMw aliphatic diamines as chain extenders are prepared via the reversible reaction of CO2 with diamines. The phase separation, thermal properties, and thermomechanical and mechanical properties of polyurethane materials are investigated as the chain extender changed from diol to diamine. Replacing the diol chain extenders with diamine results in the formation of more abundant and stronger hydrogen bonds in PUUEs, which enables the assembly of long range ordered structures and improved microphase separation. The tensile strengths of PUUEs, from 8.4 to 13 MPa, are much higher than their corresponding polyurethanes, owing to the physical crosslinks formed by the more and stronger hydrogen bonds in the PUUEs.
Poly(dl‐Lactic Acid)‐Based Linear Polyurethanes Capable of Forming Physical Crosslinking via UPy Quadruple Hydrogen Bonding Assembly
Authors: Chen Yimei , Meng Yanli , Luo Yanfeng , Wang Yuanliang
Published: June 2020

Linear shape memory polyurethanes based on poly(dl‐lactic acid) (PDLLA) macrodiol (PDLLA‐SMPUs) have various advantages such as good processability, biodegradability, shape memory effect, and biocompatibility, yet the insufficient mechanical properties prevent their effective applications in bone repair. 2‐Ureido‐4[1H]‐pyrimidone (UPy) can form strong quadruple hydrogen bonding. Here, a new linear PDLLA‐SMPU containing pendant UPy units (UPy‐p‐PDLLA‐SMPU) is designed and synthesized. The pendant UPy units may dimerize to form physical crosslinking among UPy‐p‐PDLLA‐SMPU chains. As a result, UPy‐p‐PDLLA‐SMPU demonstrates both good processability and significantly higher mechanical properties than the corresponding linear PDLLA‐SMPU without pendant UPys. In addition, UPy‐p‐PDLLA‐SMPU shows excellent shape memory effect near body temperature, with a shape fixity ratio of up to 98.6% and a recovery ratio of up to 92.9%. This work provides a new strategy to design SMPUs integrating the merits of linear and crosslinked polyurethanes, and the obtained UPy‐p‐PDLLA‐SMPU is a promising material for bone tissue repair in view of the mechanical, thermal, and shape memory properties.
GLOBAL AND TARGETED PROFILING OF GTP‐BINDING PROTEINS IN BIOLOGICAL SAMPLES BY MASS SPECTROMETRY
Authors: Huang Ming , Wang Yinsheng
Published: June 2020

GTP‐binding proteins are among the most important enzyme families that are involved in a plethora of biological processes. However, owing to the enormous diversity of the nucleotide‐binding protein family, comprehensive analyses of the expression level, structure, activity, and regulatory mechanisms of GTP‐binding proteins remain challenging with the use of conventional approaches. The many advances in mass spectrometry (MS) instrumentation and data acquisition methods, together with a variety of enrichment approaches in sample preparation, render MS a powerful tool for the comprehensive characterizations of the activities and expression levels of various GTP‐binding proteins. We review herein the recent developments in the application of MS‐based techniques, together with general and widely used affinity enrichment approaches, for the proteome‐wide and targeted capture, identification, and quantification of GTP‐binding proteins. The working principles, advantages, and limitations of various strategies for profiling the expression level, activity, posttranslational modifications, and interactome of GTP‐binding proteins are discussed. It can be envisaged that future applications of MS‐based proteomics will lead to a better understanding about the roles of GTP‐binding proteins in different biological processes and human diseases. © 2020 John Wiley & Sons Ltd. Mass Spec Rev.
A Multiscale Approach for Estimating Permeability Properties of Polymers with Complex Aromatic Backbones: A Case Study on Diffusivity of Small Gas Molecules in Polyphenylene Ether
Authors: Sweere Augustinus J. M. , Patham Bhaskar , Sugur Vijayakumar , Handgraaf Jan‐Willem
Published: June 2020

State‐of‐the‐art multiscale computational chemistry simulations is employed to predict diffusivity of small gaseous molecules in a generic polyphenylene ether (PPE). The diffusivities are obtained from trajectory analysis of gaseous molecules in molecular dynamics simulations using coarse‐grained dissipative particle dynamics (DPD) simulations to design the amorphous starting structure. Required intra‐ and intermolecular parameters of the DPD simulations are automatically generated using the automated fragmentation and parametrization protocol. A comparison of calculated diffusion coefficients with experimental data for five gaseous molecules in PPE shows adequate accuracy of computational‐chemistry‐based approaches in the prediction of diffusion coefficients. These estimates, validated against measurements reported in the literature, serve as proof of concept for applicability of these new multiscale modeling strategies for complex polymers with aromatic backbones.
Unconnected Body Accrual of Dietary Lipid and Protein in Rats Fed Diets with Different Lipid and Protein Content
Authors: Oliva Laia , Aranda Tania , Alemany Marià , Fernández‐López José‐Antonio , Remesar Xavier
Published: June 2020

Scope

Eating large amounts of fat is usually associated with fat accumulation. However, different types of diets (not only lipids) elicit different metabolic responses.

Methods and results

Male and female rats (10 week‐old) are distributed in four groups and fed for 1 month a standard diet (SD), or this diet enriched with either lipid (high‐fat diet, HF) or protein (high‐protein diet, HP), or a cafeteria diet (CAF). Both HF and CAF diets share the percentage of energy from lipids (40%) but these are different. Protein‐derived energy in the HP diet is also 40%. Feeding SD, HF, and HP diets does not result in differences in energy intake, energy expenditure, total body weight, or lipid content. However, the CAF‐fed groups show increases in these parameters, which are more marked in the male rats. The CAF diet increases the mass of adipose tissue while the HF diet does not.

Conclusion

Different diets produce substantial changes in the fate of ingested nutrient energy. Dietary lipids are not essential for sustaining an increase in body lipid (or adipose tissue) content. Body protein accrual is unrelated to dietary lipids and overall energy intake. Both protein and lipid accrual are more efficient in male rats.
A quantitative analysis of biomechanical lung model consistency using 5DCT datasets
Authors: Stiehl Brad , Lauria Michael , O'Connell Dylan , Hasse Katelyn , Barjaktarevic Igor Z. , Lee Percy , Low Daniel A. , Santhanam Anand P.
Published: June 2020

Purpose

Lung biomechanical models are important for understanding and characterizing lung anatomy and physiology. A key parameter of biomechanical modeling is the underlying tissue elasticity distribution. While human lung elasticity estimations do not have ground truths, model consistency checks can and should be employed to gauge the stability of the estimation techniques. This work proposes such a consistency check using a set of 10 subjects.

Methods

We hypothesize that lung dynamics will be stable over a 2–3 min time period and that this stability can be employed to check biomechanical estimation stability. For this purpose, two sets of 12 fast helical free breathing computed tomography scans (FHFBCT) were acquired back‐to‐back for each of the subjects. A published breathing motion model [five‐dimensional CT (5DCT)] was generated from each set. Both of the models were used to generate two biomechanical modeling input sets: (a) The lung geometry at the end‐exhalation, and (b) the voxel displacement map that mapped the end‐exhalation lung geometry with the end‐inhalation lung geometry. Finite element biomechanical lung models were instantiated using the end‐exhalation lung geometries. The models included voxel‐specific lung tissue elasticity values and were optimized using a gradient search approach until the biomechanical model‐generated displacement maps matched those of the 5DCT voxel displacement maps. Finally, the two elasticity distributions associated with each of the patient 5DCTs were quantitatively compared. Because the end‐exhalation geometries differed slightly between the two scan datasets, the elasticity distributions were deformably mapped to one of the exhalation datasets.

Results

For the 10 patients, on average, 90% of parenchymal voxels had <2 kPa Young’s modulus difference between the two estimations, with a mean voxel difference of only 0.6 kPa. Similarly, 97% of the parenchymal voxels had <2 mm displacement difference between the two models with a mean difference of 0.48 mm. Furthermore, overlapping elasticity histograms for voxels between −600 and −900 HU (parenchymal tissues) showed that the histograms were consistent between the two estimations.

Conclusion

In this paper, we demonstrated that biomechanical lung models can be consistently estimated when using motion‐model based imaging datasets, even though the models were created from scans acquired at different breaths.
Paradoxes of person‐centred care: A discussion paper
Authors: Summer Meranius Martina , Holmström Inger K. , Håkansson Jakob , Breitholtz Agneta , Moniri Farah , Skogevall Sofia , Skoglund Karin , Rasoal Dara
Published: June 2020

Aim

Previous research has mainly focused on the advantages of PCC and less on its disadvantages. Hence, there is a need to further explore the recent research regarding PCC from both sides. Therefore, the aim of this paper is to elucidate the advantages and disadvantages of PCC.

Design

Discussion paper.

Methods

We searched relevant literature published January 2000–March 2018 in PubMed, Medline, CHINAL, Scopus and Web of Science.

Results

The results showed that PCC can contribute to improved health and well‐being, improved mutual interaction in relationships, improved cost‐effectiveness and improved work environment, while the disadvantages can involve increased personal and financial costs, exclusion of certain groups, increased personal and financial costs, exclusion of staff's personhood and unfairness due to empathy. An analysis of the existing literature on PCC showed paradoxes, which call for further investigation.
Near infrared photopolymer for micro‐optics applications
Authors: Dika Ihab , Diot Frédéric , Bardinal Véronique , Malval Jean‐Pierre , Ecoffet Carole , Bruyant Aurélien , Barat David , Reig Benjamin , Doucet Jean‐Baptiste , Camps Thierry , Soppera Olivier
Published: June 2020

Near infrared (NIR) activable photopolymers suitable for versatile fabrication of micro‐optical elements were developed. The first main objective of this article is to show that these new photopolymers can be used for microfabrication and investigate the parameters governing the microfabrication process. The impact of photonic, physico‐chemical, and chemical parameters is discussed. High quality microstructures with a good control over their size and shape are demonstrated. The second main objective is to show practical examples of microlenses and waveguides implemented on single core and multiple core optical fibers, VCSELs, and glass slides are then presented. The NIR photosensitivity of this negative tone photoresists allows using the device source itself as to start the crosslinking process, which constitutes a convenient approach for micro‐optics self‐positioning on NIR sources and justifies the interest of such NIR photopolymer for the fabrication micro‐optical elements and optical interconnects.
Nanoparticles of Iron Nitride Encapsulated in Nitrogen‐Doped Carbon Bulk Derived from Polyaniline/Fe2O3 Blends and Its Electrochemical Performance
Authors: He Tianqi , Tu Mengyuan , Zhang Junlei , Kong Lingbin , Ran Fen
Published: June 2020

Iron nitride nanoparticles encapsulated in nitrogen‐doped carbon bulk is fabricated by a simple costep nitridation of Fe2O3 and carbonization of polyaniline. The microstructure and elemental composition of the materials are analyzed by transmission electron microscope, scanning electron microscope, X‐ray diffraction, and X‐ray photoelectron spectroscopy. The pore size distribution and specific surface area of the materials are identified using nitrogen adsorption and desorption method. The results illustrate that iron nitride nanoparticles with 5–20 nm in size are uniformly dispersed in the carbon bulk. The presence of carbon bulk effectively prevents the agglomeration of iron nitride nanoparticles, making the electrochemical performance of iron nitride nanoparticles/carbon nitride composite nanomaterials superior to that of pure iron nitride nanomaterials. At a current density of 0.5 A g−1, the specific capacitance (257.5 F g−1) of the iron nitride nanoparticles/nitrogen‐doped carbon bulk is much higher than that (119.5 F g−1) of pure iron nitride.
Efficiency of budesonide delivery via a mesh nebulizer in an in‐vitro neonatal ventilator model
Authors: Esmaeilizand Rana , Rocha Taciano , Harrison Ava , Gray Shari , Fusch Gerhard , Dolovich Myrna , Mukerji Amit
Published: June 2020

Objective

To determine the delivery efficiency of budesonide aerosol via a mesh nebulizer in a neonatal ventilator model.

Design/Method

In an in‐vitro ventilated neonatal model, budesonide suspension was administered using a mesh nebulizer. A collection filter was placed distal to the endotracheal tube and budesonide captured by the filter was measured using UV spectroscopy. The ventilator was, in turn, either on high frequency or conventional ventilation mode and the nebulizer was placed either proximal (close to the endotracheal tube) or distal (between the wet side of humidifier and the inspiratory circuit). Each combination (nebulizer position and ventilation mode) to assess budesonide delivery was tested five times.

Results

Overall delivery of budesonide to the distal end of the endotracheal tube a small percentage of the total dose administered. The deposition with conventional ventilation was 2.12% (±1.06) and 1.26% (±0.27), with proximal and distal placement of the nebulizer, respectively. With high‐frequency ventilation, the deposition percentages were 1.82% (±0.82) and 1.69% (±0.23), with proximal and distal nebulizer placement, respectively.

Conclusion

Only a small percentage of administered budesonide is delivered to the distal endotracheal tube, irrespective of ventilation mode, and nebulizer placement.
Numerical Research on the Impinging Effect of Sequential Muzzle Blast Waves Formed by Successive Shooting at High Frequency
Authors: Li Pengfei , Zhang Xiaobing
Published: June 2020

The impingement of muzzle blast wave is an important engineering problem and has been widely discussed for decades. The problem becomes more complex when the cannon shots at a high frequency. An accumulation phenomenon of the impingement of multiple blast waves is observed. In this research, the numerical study on impinging flows, which are generated by the propellant gas released from the muzzle of a high‐frequency launch system, is achieved. The interior ballistics model is employed in the simulation of muzzle flow. In order to have insight into the effect of continuous impingement, three cases with different launch frequencies are studied and compared. Under the computational load of muzzle flow impingement, the dynamic response of monitoring equipment is discussed based on an elastic mechanics model, and the contribution of the impinging frequency to the damaging effect is analyzed. It can be concluded that the frequency of the muzzle flow impingement has an important influence on the damaging effect. Furthermore, the accumulation of impingement depends on the shooting frequency and the intensity of each impingement.
A C‐type lectin with dual‐CRD from Tribolium castaneum is induced in response to bacterial challenge
Authors: Bi Jingxiu , Ning Mingxiao , Li Jia , Zhang Ping , Wang Lumen , Xu Shi , Zhong Yi , Wang Ziyi , Song Qisheng , Li Bin
Published: June 2020

BACKGROUND

C‐type lectins (CTLs), a group of pattern recognition receptors, are involved in regulating the immune response of insects and could be used as potential targets for pest control. However, information about roles of CTLs in the innate immunity of Tribolium castaneum, a serious, worldwide pest that damages stored grain products, is relatively scarce.

RESULTS

Here, a CTL with dual carbohydrate recognition domains (CRDs) containing a highly conserved WHD (Trp53‐His54‐Asp55) motif was identified in T. castaneum and named as TcCTL3. Spatiotemporal analysis showed that TcCTL3 was highly expressed in all developmental stages except early eggs, and mainly distributed in central nervous system and hemolymph. The transcript levels of TcCTL3 were significantly increased after lipopolysaccharide (LPS) and peptidoglycan (PGN) stimulation. Recombinant TcCTL3 was able to bind directly to LPS, PGN and all tested bacteria and induce a broad spectrum of microbial agglutination in the presence of Ca2+. The binding was shown mainly through CRD1 domain of TcCTL3. When TcCTL3 was knocked down by RNA interference, expression of nine antimicrobial peptides (AMPs) (attacin1, attacin2, attacin3, defensins1, defensins2, coleoptericin1, coleoptericin2, cecropins2 and cecropins3) and four transcription factors (TFs) (dif1, dif2, relish and jnk) were significantly decreased under LPS and PGN stimulation, leading to increased mortality of T. castaneum when infected with Gram‐positive Staphylococcus aureus or Gram‐negative Escherichia coli infection.

CONCLUSION

TcCTL3 could mediate the immune response in T. castaneum via the pattern recognition, agglutination and AMP expression. These findings indicate a potential mechanism of TcCTL3 in resisting bacteria and provide an alternative molecular target for pest control. © 2020 Society of Chemical Industry
Confining Tiny MoO2 Clusters into Reduced Graphene Oxide for Highly Efficient Low Frequency Microwave Absorption
Authors: Wu Cao , Chen Zhaofeng , Wang Meiling , Cao Xun , Zhang Yong , Song Pin , Zhang Tianyuan , Ye Xinli , Yang Yong , Gu Weihua , Zhou Jiadong , Huang Yizhong
Published: June 2020

Herein, a supermolecular‐scale cage‐confinement pyrolysis strategy is proposed to build two dielectric electromagnetic wave absorbents, in which MoO2 nanoparticles are sandwiched uniformly between porous carbon shells and reduced graphene oxide (RGO). Both sandwich structures are derived from hybrid hydrogels doped by two different crosslinkers (with/without oxygen bridge), which can precisely confine Mo source (e.g., PMo12). Without adding magnetic components, both absorbents exhibit excellent low frequency absorption performance in combination with electrically tunable ability and enhanced reflection loss value, which is superior over other relative 2D dielectric absorbers and satisfies the requirements of portable electronics. Notably, introducing oxygen bridges in the crosslinker generates a more stable confining configuration, which in turn renders its corresponding derivative exhibiting an extra multifrequency electromagnetic wave absorption trait. The intrinsic electromagnetic wave adjustment mechanism of the ternary hybrid absorbent is also explored. The result reveals that the elevated electromagnetic wave absorbing property is attributed to moderate attenuation constant and glorious impendence matching. The cage‐confinement pyrolysis route to fabricate 2D MoO2‐based dielectric electromagnetic wave absorbents opens a new path for the design of electromagnetic wave absorbents used in multi/low frequency.
Enhanced Thermoelectric Performance in Black Phosphorus Nanotubes by Band Modulation through Tailoring Nanotube Chirality
Authors: Chen Xin , Duan Shuai , Yi Wencai , Singh David J. , Guo Jiangang , Liu Xiaobing
Published: June 2020

Black phosphorus (BP) has attracted great attention for applications in thermoelectric devices, owing to its unique in‐plane anisotropic electrical and thermal properties. However, its limited conversion efficiency hinders practical application. Here, the thermoelectric properties of 1D BP nanotubes (BPNTs) with different tube chirality are investigated using first‐principles calculations and Boltzmann transport theory. The results reveal that variation of crystallographic orientation has a distinct impact on band dispersions, which provides a wide tunability of electronic transport. It is shown that (1,1)‐oriented BPNT structure can yield an order‐of‐magnitude enhanced thermoelectric figure of merit ZT at room temperature (as high as 1.0), compared with the bulk counterpart. The distinct enhancement is attributed to the favorable multiple band structures that lead to high carrier mobility of 2430 cm2 V−1 s−1. Further performance improvement can be realized by suitable doping, such as N‐alloying, reaching an increase of room‐temperature ZT by a factor of 3 over that of pristine BPNT. The work provides an applicable method to achieve band engineering design, and presents a new strategy of designing 1D BPNT that are promising candidates for flexible, eco‐friendly, and high‐performance thermoelectrics.
Foodborne Titanium Dioxide Nanoparticles Induce Stronger Adverse Effects in Obese Mice than Non‐Obese Mice: Gut Microbiota Dysbiosis, Colonic Inflammation, and Proteome Alterations
Authors: Cao Xiaoqiong , Han Yanhui , Gu Min , Du Hengjun , Song Mingyue , Zhu Xiaoai , Ma Gaoxing , Pan Che , Wang Weicang , Zhao Ermin , Goulette Timothy , Yuan Biao , Zhang Guodong , Xiao Hang
Published: June 2020

The recent ban of titanium dioxide (TiO2) as a food additive (E171) in France intensified the controversy on safety of foodborne‐TiO2 nanoparticles (NPs). This study determines the biological effects of TiO2 NPs and TiO2 (E171) in obese and non‐obese mice. Oral consumption (0.1 wt% in diet for 8 weeks) of TiO2 (E171, 112 nm) and TiO2 NPs (33 nm) does not cause severe toxicity in mice, but significantly alters composition of gut microbiota, for example, increased abundance of Firmicutes phylum and decreased abundance of Bacteroidetes phylum and Bifidobacterium and Lactobacillus genera, which are accompanied by decreased cecal levels of short‐chain fatty acids. Both TiO2 (E171) and TiO2 NPs increase abundance of pro‐inflammatory immune cells and cytokines in the colonic mucosa, indicating an inflammatory state. Importantly, TiO2 NPs cause stronger colonic inflammation than TiO2 (E171), and obese mice are more susceptible to the effects. A microbiota transplant study demonstrates that altered fecal microbiota by TiO2 NPs directly mediate inflammatory responses in the mouse colon. Furthermore, proteomic analysis shows that TiO2 NPs cause more alterations in multiple pathways in the liver and colon of obese mice than non‐obese mice. This study provides important information on the health effects of foodborne inorganic nanoparticles.
In Situ TEM Observations of Discharging/Charging of Solid‐State Lithium‐Sulfur Batteries at High Temperatures
Authors: Wang Zaifa , Tang Yongfu , Zhang Liqiang , Li Meng , Shan Zhiwei , Huang Jianyu
Published: June 2020

Understanding the structural evolution of Li2S upon operation of lithium‐sulfur (Li‐S) batteries is inadequate and a complete decomposition of Li2S during charge is difficult. Whether it is the low electronic conductivity or the low ionic conductivity of Li2S that inhibits its decomposition is under debate. Furthermore, the decomposition pathway of Li2S is also unclear. Herein, an in situ transmission electron microscopy (TEM) technique implemented with a microelectromechanical systems (MEMS) heating device is used to study the precipitation and decomposition of Li2S at high temperatures. It is revealed that Li2S transformed from an amorphous/nanocrystalline to polycrystalline state with proceeding of the electrochemical lithiation at room temperature (RT), and the precipitation of Li2S is more complete at elevated temperatures than at RT. Moreover, the decomposition of Li2S that is difficult to achieve at RT becomes facile with increased Li+ ion conduction at high temperatures. These results indicate that Li+ ion diffusion in Li2S dominates its reversibility in the solid‐state Li‐S batteries. This work not only demonstrates the powerful capabilities of combining in situ TEM with a MEMS heating device to explore the basic science in energy storage materials at high temperatures but also introduces the factor of temperature to boost battery performance.
Single Ni Atoms Anchored on Porous Few‐Layer g‐C3N4 for Photocatalytic CO2 Reduction: The Role of Edge Confinement
Authors: Cheng Lei , Yin Hui , Cai Chao , Fan Jiajie , Xiang Quanjun
Published: June 2020

It is greatly intriguing yet remains challenging to construct single‐atomic photocatalysts with stable surface free energy, favorable for well‐defined atomic coordination and photocatalytic carrier mobility during the photoredox process. Herein, an unsaturated edge confinement strategy is defined by coordinating single‐atomic‐site Ni on the bottom‐up synthesized porous few‐layer g‐C3N4 (namely, Ni5‐CN) via a self‐limiting method. This Ni5‐CN system with a few isolated Ni clusters distributed on the edge of g‐C3N4 is beneficial to immobilize the nonedged single‐atomic‐site Ni species, thus achieving a high single‐atomic active site density. Remarkably, the Ni5‐CN system exhibits comparably high photocatalytic activity for CO2 reduction, giving the CO generation rate of 8.6 µmol g−1 h−1 under visible‐light illumination, which is 7.8 times that of pure porous few‐layer g‐C3N4 (namely, CN, 1.1 µmol g−1 h−1). X‐ray absorption spectrometric analysis unveils that the cationic coordination environment of single‐atomic‐site Ni center, which is formed by Ni‐N doping‐intercalation the first coordination shell, motivates the superiority in synergistic N–Ni–N connection and interfacial carrier transfer. The photocatalytic mechanistic prediction confirms that the introduced unsaturated Ni‐N coordination favorably binds with CO2, and enhances the rate‐determining step of intermediates for CO generation.
A system concept representation framework and its testing on patents, urban architectural patterns, and software patterns
Authors: Menshenin Yaroslav , Crawley Edward
Published: June 2020

The development of a concept for a system is a key step toward creating the system's architecture. Most previous concept development approaches focus on the procedures for the conceptual design activity—the sequence of activities and tasks. Our work is motivated by the desire to elaborate in details the notional content of a system concept and to provide the means of encoding and analyzing it in a digital environment. The objective of this work is to develop a system concept representation framework that can systematically represent the concept's constituents, their definitions, and interconnections. In order to demonstrate the utility of this framework, we have conducted three studies: mapped eight selected US patents, nine selected urban architectural patterns, and three selected software patterns to the framework. Patents, urban architectural patterns, and software patterns each contain a rich body of knowledge about the system they describe, and therefore they must logically contain a description of the concepts underlying them. We show that the main features of proposed framework can be found in patents, urban architectural patterns, and software patterns. The major utility of the framework is that it provides the means to encode existing system concepts and to inform the conceptual design of new systems, contributing to the INCOSE Model‐Based Conceptual Design initiative.
Dioscorea nipponicaMakino suppressesTPA‐induced migration and invasion through inhibition of matrix metalloproteinase‐9 in human cervical cancer cells
Authors: Lee Chung‐Yuan , Chou Ying‐Erh , Hsin Min‐Chien , Lin Chiao‐Wen , Wang Po‐Hui , Yang Shun‐Fa , Hsiao Yi‐Hsuan
Published: June 2020

Dioscorea nipponicaMakino has been used for the treatment of chronic bronchitis, rheumatoid arthritis, cough, and asthma. Several studies have established the antitumor effect ofD. nipponicaMakino extract (DNE). However, no investigations have considered the antimetastatic potential of DNE in cervical cancer cells. The present study examined the effects of DNE on cervical cancer cells treated with 12‐O‐tetradecanoylphorbol‐13‐acetate and characterized the possible molecular mechanisms. MTT assay results indicated that DNE exhibited very low cytotoxicity, and DNE significantly reduced the invasion and migration abilities of cervical cancer cells. Gelatin zymography analysis revealed that DNE significantly inhibited matrix metalloproteinase‐9 (MMP‐9) activity. Reverse transcription‐polymerase chain reaction assay results revealed that DNE treatment inhibited the MMP‐9 mRNA levels of HeLa and SiHa cells. Western blot results revealed that DNE significantly diminished the ERK1/2 phosphorylation. In conclusion, we revealed that the antimetastatic effects of DNE on cervical cancer cells are due to its inhibition of MMP‐9 expression through the ERK1/2 pathway.
Climate change impacts on Australia's eucalypt and coral species: Comparing and sharing knowledge across disciplines
Authors: Booth Trevor H. , Muir Paul R.
Published: June 2020

Two of Australia's most iconic ecosystems have recently sustained heavy damage related to climatic changes: the extensive eucalypt forests from catastrophic bushfires and the Great Barrier Reef from mass coral bleaching. Despite obvious differences, eucalypt trees and reef corals share some similarities in biology and ecology, particularly in relation to climate change impacts and adaptation. Both groups are the focus of an increasing research effort to characterize and respond to climate changes and here we examine how sharing research experiences can benefit both fields. Four key areas of research are considered: (a) modeling current distributions, (b) assessing impacts of climate change on future distributions, (c) using human‐assisted migration to improve survival, and (d) applying genetic enhancement to improve the species’ survival. Examples of each research area are used to examine potential crossovers, limitations of the methods, and future requirements. We conclude that eucalypt and coral researchers, and indeed researchers for many other endangered taxa, can gain much by comparing experiences and methods, despite the apparent differences in their respective taxa.

This article is categorized under:

Assessing Impacts of Climate Change > Observed Impacts of Climate Change
Doping Effects in CMOS‐compatible CoSi Thin Films for Thermoelectric and Sensor Applications
Authors: Krishna Nichenametla Charan , Calvo Jesus , Riedel Stefan , Gerlich Lukas , Hindenberg Meike , Novikov Sergej , Burkov Alexander , Kozelj Primož , Cardoso‐Gil Raul , Wagner‐Reetz Maik
Published: June 2020

Abstract. We report on semi‐metallic cobalt monosilicide (CoSi) as a CMOS‐compatible thermoelectric (TE) material and discuss the effect of n‐ and p‐type dopants on its transport properties. Thin films of CoSi are developed using chemical vapor deposition tools and subsequent rapid thermal processing. Film properties such as microstructure, crystallinity and elemental distribution are studied via electron microscopy, X‐ray diffraction and time‐of‐flight secondary ion mass spectroscopy. Doping silicon with boron prior to silicidation impedes the Co‐Si diffusion process, while phosphorus atoms distribute uniformly in silicides with no voids or agglomerations. CoSi makes a suitable n‐type TE candidate and provides an alternative to Si or SiGe materials. Transport properties of undoped CoSi exhibit a linear dependence within the investigated temperature window, whereas dopants in CoSi increase the number of electron carriers that contribute to charge transport and thereby influence the Seebeck coefficient. Thus, TE characteristics of thin CoSi films can be tuned via (i) the type of dopants used and/or (ii) varying the residual silicon thickness post silicidation.