bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of Box-Behnken on decomposition rate of fungal lignocellulosic
Authors: Zhou Xinyi , Li Qingxin , Hong Cheng
Published: August 2021

In this paper, Box-Behnken response face model was used to establish the decomposition rate model of fungi. Based on the single factor simulation test data in the literature, this paper uses the Design-Expert 8, aiming at the peripheral range value of single factor optimization results, the orthogonal rotation combination experiment of multiple factors was designed to obtain the response surface regression model of fungi decomposition rate and temperature, time, quantity, population proportion and other factors, and to solve the optimal parameter combination; on the other hand, according to the research data of the title, taking the humidity tolerance as the link, the relationship function of fungi decomposition rate and growth rate, humidity tolerance was established by using MATLAB. Combining the two models, the decomposition rate model under the interaction of multiple fungi was established. The main factors affecting the decomposition rate of fungi were found from different angles by two methods, and different fungi were organically combined by growth rate and moisture resistance.
Study on the process of simultaneous desalting and boron removal from seawater
Authors: Kuang Bin , Li Zhensheng , Lin Ziyang , Du Siyuan , Guo Bing , Wang Tao
Published: August 2021

Two new combined technologies, reverse osmosis (RO) + electrodeionization (EDI) and reverse osmosis (RO) + ion exchange (IE), were studied for simultaneous desalination and boron removal of seawater. The results show that the RO system has excellent desalination performance under the experimental conditions, and can provide stable desalination rate for the subsequent processes of the two combined schemes. The boron concentration in water has little effect on the desalination rate of RO system, and the boron removal rate of RO system is between 47% and 50%, which provides a good early treatment for the subsequent process. The blank experiment shows that the salinity has little effect on the boron removal rate of RO-EDI equipment, and the boron removal rate is more than 93%, which has excellent and stable boron removal performance, but the water yield of RO-EDI equipment is low (less than 60%). The RO-IE system has a high water yield (> 70%), but the equipment has poor adaptability to influent boron concentration and salinity. The results of effluent water show that the boron concentration of raw water by RO-EDI combined process can be adapted to a wider range, and the influence of salinity is less. Considering comprehensively, RO-EDI process has more advantages and broad application prospects.
Discussion on the temperature influence of Pb/Cu/Ni/Mo precipitation in copper faucets
Authors: Tingting Huang , Renjie Chen , Wenjia Huang , Jiannan Wang , Liping Guo , Meimei Xie , Jinzhang Cai
Published: August 2021

Precipitation of harmful substances in the faucets has always been the focus of attention, this experiment selected the four metal elements of Pb/Cu/Ni/Mo as the research object, and studied the precipitation in the faucets which were extracted at the ambient temperature of 20°C, 40°C and 60°C. The results showed that the Pb and Mo precipitation in the faucets increased with the temperature rise, while the Cu and Ni in most samples were the least precipitated at 60°C. Detection found that the metals precipitation among different batches and different samples in the same batch varied widely, mainly affected by the processing technology and the material of faucets.
Synthesis of ZIF-69-derived Electrocatalyst with Low loading Platinum for Oxygen Reduction Reaction
Authors: Liu Xiaoyu
Published: August 2021

Here, we report a facile preparation of a low-platinum catalyst derived from ZIF-69 denoted as Pt@ZC-69. Nitrogen-abundant ZIF-69 could act as a support to efficiently encapsulate trimethyl (methylcyclopentadienyl) platinum (IV) (MeCpPtMe3@ZIF-69) precursor. After high-temperature reduction, Pt@ZC-69 with uniform Pt-loading was obtained. In the acidic medium, the Pt@ZC-69 presented a desirable performance, the half-wave potential could reach 0.845 V vs. RHE, while the Pt content is less than 10% of the commercial 20 wt.% Pt/C. Moreover, Pt@ZC-69 also possessed robust stability (40 mV decays after 20000 cycles).
Effect of ethanol extract from chestnut flower on nitrite content in pickles
Authors: Siyu Shi , Haibin Li , Yu Hao , Wenhui Liang , Fang Wang , Meixia Pang , Jinghua Qi
Published: August 2021

In this paper, chestnut flowers from the Huairou District of Beijing were used as experimental materials. It was aimed to explore the removal effect of nitrite by ethanol extract simulation system of chestnut flower and its impact on nitrite in food. The content of nitrite was measured by the naphthalene ethylenediamine hydrochloride method. In the experiment, the ethanol extract of chestnut flower was added when pickling vegetables. During pickling, adding the ethanol extract of chestnut flower could decrease the content of nitrite. As a consequence, the peak of nitrite was delayed one day due to the addition of 0.2 g/mL ethanol extracting from the chestnut flower.
Light and Thermal Induced Spin Crossover Properties of Fe(II) Compound
Authors: Zhao Qi
Published: August 2021

We synthesized a novel phenanthroline-based mononuclear Fe(II) compound [Fe(TTD)2(NCS)2]⋅CH3CN (1, TTD = 1,4,8,9-tetraaza-triphenylene-2,3-dicarbonitrile). And its crystal structure, optical and magnetic properties were analyzed. The thermally induced SCO of the compound is a one-step abrupt transition. In addition, light can also control the spin state of the compound. By using 660 nm light-excited compound, LIESST (light-induced excited spin-state trapping) effect can be achieved.
Effects of Intercropping on the Chemical Forms of Pb and Cd in Cyperus glomeralus and Zea mays.
Authors: Wang Jun , Zhao Mimi , Lei Mengmeng , Qin Li
Published: August 2021

Pot experiment was carried out to study the chemical form of Pb and Cd in two plants under the condition of Cyperus glomeratus and Zea mays intercropping. The results showed that: (1) The chemical form of Pb in two plants are mainly FNaCl and FR. Compared with monoculture, Pb content of various chemical forms in C. glomeratus increased by 5.88%~300% under intercropping, and decreased by 5.69%~47.69% in Z. mays. (2) The chemical form of Cd in both plants are FNaCl and FHCl, the FR Cd contents in the shoot of C. glomeratus increased by 21.45% and the FW, FHCl and FR Cd contents increased by 12.06%~33.33% under intercropping system; the FHCl Cd contents in the shoot of Z. mays decreased by 21.84% and the FW, FNaCl, FHAC and FR Cd contents in the root of Z. mays decreased by 12.96%~61.03% under intercropping system comparing with monoculture system. It is shown that intercropping of C. glomeralus and Z. mays affects the chemical form of Cd and Pb in plants, promoting the absorption and accumulation of Pb and Cd in C. glomeralus, and inhibiting the accumulation of in Z. mays.
Preliminary Study on Application of Infrared Thermal Imaging Technology in Combustion Control of Coal-fired Boilers
Authors: Zhang Zi-Guo
Published: August 2021

The principle of infrared thermal imaging is briefly described. According to the actual situation of the boiler and the investment cost, the location and quantity of the infrared cameras are analyzed, it is reasonable to set up an infrared camera on both sides of the end of the boiler grate for combustion monitoring. In addition, the thermal image of coal combustion in the boiler furnace monitored by the infrared cameras are analyzed and researched. It is concluded that the infrared thermal imaging technology can be applied to the combustion monitoring of coal-fired boilers, which is beneficial to saving coal, energy saving and environmental protection.
The influence of alkalinity on the two stages of S0-based autotrophic denitrification
Authors: Li Yong , Zhang Xiaolei , Li Ji
Published: August 2021

In this study, two S0 particle packed reactors were constructed to explore the influence of alkalinity content on S0-based autotrophic denitrification (SAD) with nitrate and nitrite as electron acceptors respectively. As a result of the comparative experiment, when the alkalinity of influent is sufficient (HCO3
-: NO3
- mole ratio > 1.5:1), NO3
--N and NO2
--N reactor both showed high removal efficiency. But when the HCO3
-: NO3
- mole ratio decreased to 0.2:1, the average removal rate of NO3
--N decreased to 31%, and NO2
--N average removal rate still maintained at 95%. Based on the results, the reduction of alkalinity can significantly reduce the nitrate removal efficiency, but has little effect on the nitrite removal efficiency. This study further explained the characteristics of alkalinity consumption of the two stage of SAD and may provide a reference for future research.
Influence of temperature on ethylene octene-1 copolymerization catalyzed by supported metallocene catalyst
Authors: Dengfei Wang , Jian Wang , Shuyan He , Yibin Yan , Guoxing Yang , Xinglong Zhao , Feng Guo
Published: August 2021

A supported (nBuCp)2ZrCl2 metallocene catalyst was prepared and used in the slurry copolymerization of ethylene/octene-1 with triethylaluminium (TEAL) as co-catalyst. The effects of polymerization temperature on the properties of both the catalyst and resulted copolymers were investigated. The results show that the yield of supported metallocene catalyst reaches 4.3 kgPE/gcat and the bulk density of PE is higher than 0.4 g/cm3, the fines content of the polymer is less than 12.0 wt%, and the molecular weight distribution (MWD) of products ranges from 2.9 to 4.0 within the polymerization temperature range of 73~88 °C. These results are beneficial for large-scale industrialization of supported metallocene catalysts, and also provide a reference for academic research.
Preparation of Graphene and its application in lithium batteries
Authors: Ma Zhikun
Published: August 2021

The dual-carbon nanomaterial graphene has attracted the attention of scientific researchers all over the world because of its excellent properties and structure. Among them, graphene as anode material for lithium battery is a hot topic. In this study, the properties of graphene, the preparation method of graphene, the application prospect of modern graphene and the existing preparation methods are discussed.
Research on Technological Development Status of New Energy Vehicles Based on Hydrogen Fuel Cells
Authors: Sining Ma , Peigen Shen
Published: August 2021

As an electric energy conversion medium with economic value, hydrogen energy, which is storable and highly adapted to new energy, can be used as an energy storage medium to ensure the stable output of energy and the continuous running of vehicles in the context of the continuous deterioration of the global environment and the constant decline of the total amount of traditional fossil fuels. This paper summarized the development status of hydrogen fuel vehicles and development characteristics of corresponding technologies, and studied the technological development status of hydrogen fuel cell vehicles (HFCEVs) through the analysis of hydrogen energy for vehicles and through summaries of the development of hydrogen fuel vehicles and key technologies of hydrogen fuel cells.
Energy Consumption Model for pulse-laser Selective Laser Melting
Authors: Hui Jizhuang , Huang Jian , Yan Zhiqiang , Zhang Hao
Published: August 2021

As a widely used additive manufacturing (AM) technology, the selective laser melting (SLM) technology shows great potential for the sustainable development. Therefore, it is essential to conduct an accurate prediction of the AM energy consumption. In this paper, a new prediction method of SLM energy consumption is proposed. Through analysing the working states of each machine subsystem, this method established an energy consumption prediction model concerning the exposure time, point distance, laser power, and hatch spacing based on the characteristics of the pulse-laser-SLM machine. The model contributes to the improvement and optimization of the energy consumption prediction accuracy in the printing stage.
The design and forming of composite heteromorphic components
Authors: ming JIANG , shicheng LI , tao SHEN , chun ZHUANG , bin DONG , jie TIAN
Published: August 2021

In order to meet the weight reduction requirement of a tactical component, feasibility analysis by selected raw material, analyzing the stress and displacement under the working condition by finite element analysis method, a design of molding and curing are proposed. The results of feasibility by choosing suitable show that the mass of the composite component is reduced from 8.3Kg to 2.9Kg after optimization with the theoretical weight loss is 60%; the maximum stress is 50.9 MPa and the maximum displacement is 0.089mm; which meet the design requirement. The internal expansion pressure of the mold is designed as 1.0 MPa which meets the molding requirement. The design of this lightweight tactical composite component is clear, reasonable and feasible, which will have a certain guiding significance for the research of molding technology in related field.
Glypican-3 electrochemical aptasensor based on CuO-rGO nanocomposite
Authors: Feng Huafu , Bao Mingming , Lian Mei , Li Guiyin
Published: August 2021

Herein, a novel electrochemical immunosensor was fabricated based on copper oxide-reduction graphene oxide (CuO-rGO) nanocomposites for Glypican-3 (GPC3) detection. Firstly, CuO-rGO nanocomposite as nanoenzyme with good peroxidase-like properties is synthesized by One-step hydrothermal. Then CuO-rGO nanoenzyme captures GPC3 aptamer to form a signal probe, finally GPC3 antibody is used as the recognition probe to form an "antibody-antigen-aptamer" sandwich structure. Due to the peroxidase-like properties of the probe, this sandwich structure can effectively catalyze the reaction between hydrogen peroxide (H2O2) and silver nitrate (AgNO3) and AgNPs is deposited on the surface of the electrode to amplify the final measured current. The Differential Pulse Voltammetry (DPV) method was employed to record the response signal of the immunosensor. The current response presented a linear relationship to the GPC3 concentration in the range of 1 to 40 μg/mL with the detection limit of 0.45 μg/mL.
Research on Monitoring Method of Fuel Sulfur Content of Ships in Tianjin Port
Authors: Songbo Qi , Jiguang Wang , Xiaowen Zhang , Zhiwen Yang , Zhenkai Xie , Jingyuan Li
Published: August 2021

Fuel sulfur content of marine sailing within the emission control area should not exceed 0.5%. Traditional boarding inspections are difficult, inefficient, and poorly targeted. Remote monitoring of air pollutants from ships is required to screen unqualified ships. The article investigates the topographical conditions and weather conditions of Tianjin Port, selects the technology of existing monitoring methods, elaborates and analyzes the composition and working principle of the current monitoring system, and finally forms a monitoring method of fuel sulfur content of ships in Tianjin Port.
Preparation of Porous Carbon Nanorods by Cellulose Template Method and Their Supercapacitor Properties
Authors: Yu Wei , Jingxun Zhang , Jiatong Wang , Mengyuan Liu , Lu Sun
Published: August 2021

Aiming at the properties of carbon materials, this article synthesized porous carbon nanorod materials by cellulose template method and characterized them by various analysis methods. The results show that these porous carbon nanorod materials have unique morphology and excellent electrochemical performance. It can be seen that these porous carbon nanorod materials have potential application value in capacitors.
Effect of excess air coefficient on the combustion characteristics of a multi-stage dual swirl burner
Authors: Fan Huanbao , Feng Junxiao , Hu Wenhao , Li Weidong , Gao Jun
Published: August 2021

This study proposed a multi-stage dual swirl burner for heating furnaces to achieve low nitrogen oxide (NOx) emissions based on swirling combustion and staging combustion technology. The effect of excess air coefficient on combustion characteristics and NOx emissions was studied by numerical simulation. The flow field, temperature field, oxygen concentration, and the NOx concentration distributions of the burner were discussed and analysed in detail. The simulated results showed that two recirculation zones for entrained flue gas formed in the reaction process by swirl blades. Meanwhile, increasing the excess air coefficient can improve the fuel/air mixing rate and diffusion effect in the combustion chamber, reducing the maximum combustion temperature and NOx emissions. Furthermore, when the excess air coefficient increased from 1.1 to 1.4, the maximum flame temperature was reduced from 1918.3 K to 1819.6 K, and the mole fraction of NOx at the outlet decreased from 1.67×10-6 to 0.77×10-6, which revealed the potential of the burner for the clean combustion.
Lithiophilic coating layer modify three-dimensional Cu foam for stable and dendrite-free lithium metal anode
Authors: Huang Kai , Song Shipai , Xiang Yong
Published: August 2021

The widespread research for lithium metal anodes (LMA) has been rapidly developed in recent years. However, undesirable dendritic structures generated in the process of unstable lithium (Li) deposition dramatically restricts the cycle life of LMA. The skeleton structure of the three-dimensional (3D) host substrates are the potential promising host for Li, which can alleviate volume expansion during cycling. Herein, we propose a facile surface modification approach through ion sputtering, which can effectively regulate the lithiophilic properties of Cu foam (CF) for facilitating Li deposition. Au modified surface can enhance the lithiophilic property of substrates and induce uniform Li deposition along the conductive skeleton. Further analysis of results, substrate with Au coating modified surface exhibits a smaller Li nucleation overpotential (12 mV), a more stable coulombic efficiency (CE) at different current densities, and more uniform morphology of Li deposition with dendrite-free at large capacity of 4 mAh cm-2. Meanwhile, symmetric cells with Au coating on CF can stably operate more lifespan than other samples. Furthermore, full cells paired with LiFePO4 cathodes and CF coated Au exhibit remarkable discharge capacities and capacity retention than others. This work provides new insights toward developing excellent 3D skeleton with modified surface for dendrite-free LMA.
Experimental Study on Surface Electric Field Distribution and Flash-over Voltage of Bushing Composite Insulator at High Altitude
Authors: Shiling Zhang , Xin Liang , Hua Yin
Published: August 2021

At present, the high voltage bushing composite insulator is widely used in AC/DC system substation, and its structural parameters show the nonlinear growth trend with the increase of voltage level. Therefore, in 1000kV UHVAC and 800kV UHVDC system, bushing composite insulator has the typical characteristics of long insulation distance and large radial diameter. At present, with the proposal of high-voltage power equipment compact optimization design scheme, the radial diameter of the composite insulator for bushing can be effectively reduced by reasonable design of internal capacitor core or metal shield structure optimization design scheme, so as to realize its large aspect ratio compact design. On the other hand, the insulation distance of high voltage bushing composite insulator will be further increased when it is applied in high altitude area. The innovation of this paper is how to carry out flashover voltage test to fill the current test data gap. In view of this, this paper first establishes two typical structures of the high voltage bushing composite insulators, including the three-dimensional finite element models of the composite insulators for capacitive core converter transformer bushing and the double-layer metal shield through the wall bushing, obtains the distribution characteristics of typical voltage and electric field under the operating state, and analyzes the local high field strength and corona, the electric field distribution of composite insulators for bushing. Furthermore, the actual flashover tests between large fittings air metal grounding body and large fittings composite insulator metal grounding body are carried out in the laboratory environment, and the quantitative relationship curve between flashover voltage and space net distance is obtained. Based on the above theoretical analysis and test data, the size altitude correction and umbrella skirt contour topology optimization of composite insulator for the UHV AC/DC bushing are carried out. Finally, the DC withstand voltage test and one minute power frequency withstand voltage test are passed, which proves the rationality and effectiveness of the design of composite insulator for bushing at UHV level. In this paper, starting from the typical electric field distribution characteristics of all kinds of composite insulators for bushing, the flashover law is studied for the first time, and the flashover test is carried out in the laboratory to supplement the classical test data. The research results have good theoretical and practical significance for installation, design and operation maintenance of all kinds of composite insulators.
Co-production of knowledge reveals loss of Indigenous hunting opportunities in the face of accelerating Arctic climate change
Authors: Hauser Donna D W , Whiting Alex V , Mahoney Andrew R , Goodwin John , Harris Cyrus , Schaeffer Robert J , Schaeffer Roswell , Laxague Nathan J M , Subramaniam Ajit , Witte Carson R , Betcher Sarah , Lindsay Jessica M , Zappa Christopher J
Published: August 2021

Profound sea ice loss is rapidly transforming coupled social-ecological Arctic marine systems. However, explicit impacts to harvesting of traditional resources for coastal Indigenous communities remain largely unquantified, particularly where the primary research questions are posed by the Indigenous community as a result of emerging approaches such as knowledge co-production. Here, we directly link reduced sea ice coverage to decreasing harvesting opportunities for ugruk (bearded seal, Erignathus barbatus) as a component of a partnership among a multidisciplinary team of scientists, Indigenous Elder Advisory Council, and sovereign Indigenous tribe in northwest Alaska, USA. We collaboratively established research questions, coordinated data collection, and interpreted results to understand the causes and consequences of changing ugruk harvests for the community of Qikiqtaġruk (Kotzebue). The duration of spring ugruk hunts by the Qikiqtaġruŋmiut declined significantly during 2003–2019 due to a shift (∼3 weeks earlier) in the timing of regional sea ice breakup. Harvests now cease ∼26 d earlier than in the past decade. Using historical sea ice records, we further demonstrate that ice coverage in May now resembles conditions that were common in July during the mid-20th century. Overall, we show that climate change is constraining hunting opportunities for this traditional marine resource, although Qikiqtaġruŋmiut hunters have so far been able to offset a shortened season with changes in effort. Notwithstanding recent hunting success in unprecedentedly sparse ice conditions, accessibility to traditional resources remains a prominent concern for many Arctic communities. Management and policy decisions related to Arctic marine mammal resources, such as ugruk, are therefore also interwoven with food security, well-being, and culture of Indigenous communities. Hence, research that originates with Indigenous sovereignty over the entire research process, such as demonstrated here, has the potential to also lead to more inclusive, sustainable, and equitable outcomes in the face of rapid and accelerating Arctic change.
Seasonally dynamic nutrient modeling quantifies storage lags and time-varying reactivity across large river basins
Authors: Schmadel Noah M , Harvey Judson W , Schwarz Gregory E
Published: August 2021

Nutrients that have gradually accumulated in soils, groundwaters, and river sediments in the United States over the past century can remobilize and increase current downstream loading, obscuring effects of conservation practices aimed at protecting water resources. Drivers of storage accumulation and release of nutrients are poorly understood at the spatial scale of basins to watersheds. Predicting water quality outcomes in large river basins demands modeling storage lags and time varying reactivity that models of mean conditions typically cannot elucidate. We developed a seasonally dynamic approach to large-scale nutrient modeling based on a multiscale framework and nutrient storage lags were quantified for the nearly 190 000 small catchments that feed the rivers across the northeastern United States where catchment mean transit times were found to be around 4.7 (2–10) years for nitrogen and 1.3 (0.7–2) years for phosphorus. Nutrient loads carried in river flow in the current season contained a significant—and sometimes dominant—portion of mass lagged in its release from catchment storage repositories. Our approach of integrating storage releases with seasonally dynamic hydroclimatic drivers sets the stage to assess the accumulated effects of nutrient storage and lagged releases to the river interacting with seasonally varying nutrient reactivity and societal management actions throughout large river basins.
Comprehensiveness of circular economy assessments of regions: a systematic review at the macro-level
Authors: Van Bueren Bart J A , Iyer-Raniga Usha , Leenders Mark A A M , Argus Kevin
Published: August 2021

The circular economy (CE) is emerging as a solution for a thriving economy within regional and planetary boundaries for environment and social justice. CE is multifaceted with interconnected processes and therefore rather difficult to assess comprehensively. This paper reviewed the corpus of macro-level CE assessments, to find the best practices in CE assessments of regions scaling from neighborhoods to planetary. The extensive content analysis on the corpus of 165 studies used a novel mixed methods of meta-analysis, taxonomy and integrative review. This review investigates the comprehensiveness of CE assessments. Findings include three types of CE performance monitoring, four types of resource clustering, five scales, and a 5-step procedure to evaluate CE. CE can be monitored on: (a) absolute performance, quantifying economic resource-input, stock and waste-output; (b) efficiency performance, monitoring the optimization of CE processes similar to recycling, reuse, or even sharing and virtualizing; (c) policy performance to monitor strategies from regional stakeholders. Resource clustering can create hierarchies by metrics, uses, system-boundaries, or emergy. Identified scales are: XL for the planet; L for continents; M for large provinces, states and smaller countries; S for cities; and, XS for neighborhoods. Scales assist in comparing and benchmarking, but are also required for a proposed policy of localizing CE. This review found the ReSOLVE-framework as relatively comprehensive on CE processes. Also, multiple knowledge gaps were identified among resources, processes and regions. This review aids CE knowledge accumulation across regions and scales, to accelerate implementing the CE.
A study on damage evolution in Cu-TiO2 composite fabricated at different temperatures and strain rates
Authors: Jafari S S , Majzoobi G H
Published: August 2021

Copper/Titanium Dioxide (CuTiO2) samples were fabricated at three temperatures (450 °C, 650 °C, 850 °C) using: a universal testing machine (quasi-statically at the strain rate of 8 × 10–3 s−1), a drop Hammer (dynamically at the strain rate of about 8 × 102 s−1), and a modified Split Hopkinson Pressure Bar (strain rate of about 1.6 × 103 s−1). The effects of reinforcing particle size on relative density and damage parameter of Cu reinforced by 0, 2.5, 5 and 10% volume fractions of nano- and micro-sized TiO2 were investigated. The results indicated that the size of TiO2 particles, loading rate, and temperature had significant effect on relative density and damage parameter. The results also showed that the Quasi-Static method was superior to the other two methods. In addition, by increasing temperature, the mechanical properties of the composites were improved. The results showed that the effect of nano sized reinforcement particles on damage parameter was more profound than micro sized reinforcement particles. In this work, a new damage model considering the effects of strain rate, temperature, volume fraction and the aspect ratio of particles on damage parameter was proposed. The damage parameter was obtained using relative density and elasticity modulus. The results showed significant difference between the two methods. However, the density method yields more accurate and realistic results.
Super-high sensitivity FBAR temperature sensor based on size effect of Ti insertion layer
Authors: Lin Wenkui , Yun Xiaofan , Wang Xiaoyi , Zeng Zhongming , Wang Yiqun , Zhang Xiaodong , Zeng Chunhong , Zhang Baoshun
Published: August 2021

The temperature sensitivity is one of the critical parameters for the thin film bulk acoustic resonator (FBAR) based temperature sensors. In this work, FBARs with Au/Fe0.8Ga0.2/Ti/AlN/Mo structure are developed. The size effect of the Ti insertion layer on the temperature sensitivity of the devices is systematically investigated. The devices were fabricated by MEMS process and characterized by a network analyzer under variable temperatures. It is found that the temperature sensitivity of the devices is strongly related to the thickness of the Ti insertion layer. A super-high temperature sensitivity up to 546 kHz °C−1 was obtained with 20 nm Ti inserted thin film; that feature can even reach 825 kHz °C−1 for some devices, showing great potential for ultra-sensitive temperature monitoring. Mason model is used to analyze the extraordinary characteristics of the device and finite element method (FEM) is used to analyze the strain distribution in the device. The supreme performance of the temperature sensor can be explained by the size effect of the temperature coefficient of Young’s modulus (TCE) of Ti film, which means that the TCE was enhanced when the thickness of the Ti film is around 20 nm. This work provides a new approach for the design of high sensitivity temperature sensor based on FBAR.
Improving the mechanical properties and coefficient of thermal expansion of molybdenum-reinforced copper using powder metallurgy
Authors: Ahmadein M , El-Kady Omayma A , Mohammed M M , Essa Fadl A , Alsaleh Naser A , Djuansjah Joy , Elsheikh Ammar H
Published: August 2021

This paper presents an experimental study of Cu-Mo alloys prepared by powder metallurgy (PM) method. Also, improving the dispersion and wettability of Mo in the Cu matrix was aimed. Mo particles were added by 0.24, 0.48, 0.73 and 0.97% volume fraction to Cu powder. The mixture was mechanically milled by planetary ball mill at a rotational speed of 140 rpm for 24 h under hydrogen atmosphere, with milling ball size of ∼25 times the size of the metal powders. Liquid acetone was utilized as a process control agent (PCA). Paraffin wax (0.5 wt%) was used to decrease the friction with die during the compaction process. The mixture of the blended powder was compacted at ambient temperature under three different pressures (400, 600 and 800 MPa) and then sintered in a vacuum furnace at 1000 °C for 1 h by a heating rate of 5 °C min−1. The microstructure examination showed a homogeneous dispersion of Mo particles within the Cu matrix with no evidence of new phases formation during the sintering process. Also, the relative density of samples has been increased by increasing both of Mo content and the compaction pressure. The results revealed that the compaction pressure of 600 MPa was the most suitable pressure as it gave the highest densification. Cu—0.97% volume fraction Mo alloy samples exhibited finer Mo particles with a homogenous distribution in the Cu matrix and well bonding with the Cu particles. The microhardness was increased gradually by increasing Mo wt%, while the compressive strength was decreased by increasing the Mo contents. Both the electrical and thermal conductivities were decreased gradually by the addition of Mo. While the coefficient of thermal expansion (CTE) was decreased by Mo addition.
Early life stress affects the miRNA cargo of epididymal extracellular vesicles in mouse
Authors: Alshanbayeva Anar , Tanwar Deepak K , Roszkowski Martin , Manuella Francesca , Mansuy Isabelle M
Published: August 2021

Sperm RNA can be modified by environmental factors and has been implicated in communicating signals about changes in a father's environment to the offspring. The small RNA composition of sperm could be changed during its final stage of maturation in the epididymis by extracellular vesicles (EVs) released by epididymal cells. We studied the effect of exposure to stress in early postnatal life on the transcriptome of epididymal EVs using a mouse model of transgenerational transmission. We found that the small RNA signature of epididymal EVs, particularly miRNAs, is altered in adult males exposed to postnatal stress. In some cases, these miRNA changes correlate with differences in the expression of their target genes in sperm and zygotes generated from that sperm. These results suggest that stressful experiences in early life can have persistent biological effects on the male reproductive tract that may in part be responsible for the transmission of the effects of exposure to the offspring.
Cortactin knockdown results in disruption of basal TBCs and alters turnover of Sertoli cell ESs in Rattus norvegicus
Authors: Palia Prunveer , Adams Arlo , Sriram Aarati , Vogl A Wayne
Published: August 2021

Here we explore the prediction that long-term knockdown of cortactin (CTTN), a component of tubulobulbar complexes (TBCs), disrupts TBCs in Sertoli cells and alters the turnover of basal ectoplasmic specializations (ESs). In rats, intratesticular injections of siRNA targeting CTTN (siCTTN) in one testis and nontargeting siRNA (siControl) in the contralateral testis were done on days 0, 2, 4, 6, and 8. The experiment was terminated on day 9 and testes were analyzed by either western blotting, or by stimulated emission depletion (STED), electron and/or conventional fluorescence microscopy. Levels of CTTN were successfully knocked down in experimental testes compared to controls. When cryo-sections were labeled for actin filaments, or CTTN, and oxysterol binding protein–related protein 9 (ORP9) and analyzed by STED microscopy, TBCs were “less distinct” than in tubules of the same stages from control testes. When analyzed by electron microscopy, redundant clumps of basal actin filament containing ESs were observed in experimental sections. Using labeling of actin filaments in ESs, thresholding techniques were used to calculate the number of pixels above threshold per unit length of tubule wall in seminiferous tubules at Stage VII. Median values were higher in experimental testes relative to controls in the four animals analyzed. Although we detected subtle differences in ES turnover, we were unable to demonstrate changes in spermatocyte translocation or in the levels of junction proteins at the sites. Our results are the first to demonstrate that perturbation of basal TBCs alters the turnover of actin-related junctions (ESs).
Evaluation of postoperative surveillance strategies for esophago-gastric cancers in the UK and Ireland
Authors: Chidambaram Swathikan , Sounderajah Viknesh , Maynard Nick , Underwood Tim , Markar Sheraz R
Published: August 2021

Esophago-gastric malignancies are associated with a high recurrence rate; yet there is a lack of evidence to inform guidelines for the standardization and structure of postoperative surveillance after curatively intended treatment. This study aimed to capture the variation in postoperative surveillance strategies across the UK and Ireland, and enquire the opinions and beliefs around surveillance from practicing clinicians. A web-based survey consisting of 40 questions was sent to surgeons or allied health professionals performing or involved in surgical care for esophago-gastric cancers at high-volume centers in the UK. Respondents from each center completed the survey on what best represented their center. The first section of the survey evaluated the timing and components of follow-ups, and their variation between centers. The second section evaluated respondents perspective on how surveillance can be structured.

Thirty-five respondents from 27 centers consisting 28 consultants, 6 senior trainees and 1 specialist nurse had completed the questionnaire; 45.7% of responders arranged clinical follow-up at 2–4 weeks. Twenty responders had a specific postoperative surveillance protocol for their patients. Of these, 31.4% had a standardized protocol for all patients, while 25.7% tailored it to patient needs. Patient preference, comorbidities and chance of recurrence were considered as major factors for necessitating more intense surveillance than currently practiced. There is a significant variation in how patients are monitored after surgery between centers in the UK. Randomized controlled trials are necessary to link surveillance strategies to both survival outcomes and quality of life of patients and to evaluate the prognostic value of different postoperative surveillance strategies.
Circular RNA HECTD1 Mitigates Ulcerative Colitis by Promoting Enterocyte Autophagy Via miR-182-5p/HuR Axis
Authors: Xu Yan , Tian Yuxi , Li Fujun , Wang Ying , Yang Junwen , Gong Hui , Wan Xiaoping , Ouyang Miao
Published: August 2021

Objective

Ulcerative colitis (UC) is a chronic colitis with unknown etiology. Circular RNA (circRNA) has shown regulatory effect in many diseases, but the role of circRNA in UC is barely known. This study uncovers the function and regulatory mechanism of circRNA HECTD1 (circHECTD1) in UC.

Methods

Colonic mucosal tissues of 60 patients with active UC and 30 healthy controls were collected for H&E staining. Lipopolysaccharide (LPS) and dextran sulfate sodium (DSS) were used to induce inflammation and UC in Caco-2 cells and C57BL/6 mice where modification of circHECTD1, miR-182–5p and/or human antigen R (HuR) took place. The Caco-2 cells and the colon tissues of DSS-treated mice were collected for analysis of the expression levels of inflammatory cytokines, NLRP3 inflammasome, and autophagy-related proteins. The interactions among circHECTD1, miR-182–5p, and HuR were verified.

Results

The colonic mucosal tissues of UC patients showed impaired autophagy and decreased expressions of circHECTD1 and HuR. Overexpression of circHECTD1 or HuR or inhibition of miR-182–5p suppressed inflammation and promoted autophagy of LPS-induced Caco-2 cells. The expression of HuR was promoted by circHECTD1 via miR-182–5p in Caco-2 cells. Overexpression of circHECTD1 reduced colonic injuries and inflammation by promoting autophagy in DSS-treated mice.

Conclusion

Overexpression of circHECTD1 alleviates UC by promoting HuR-dependent autophagy via miR-182–5p. This study highlights the therapeutic potential of circHECTD1 for UC and adds to the knowledge of circRNA in the pathogenesis of UC.
Contribution of High Viral Loads, Detection of Viral Antigen and Seroconversion to Severe Acute Respiratory Syndrome Coronavirus 2 Infectivity
Authors: Buder Felix , Bauswein Markus , Magnus Clara L , Audebert Franz , Lang Henriette , Kundel Christof , Distler Karin , Reuschel Edith , Lubnow Matthias , Müller Thomas , Lunz Dirk , Graf Bernhard , Schmid Stephan , Müller Martina , Poeck Hendrik , Hanses Frank , Salzberger Bernd , Peterhoff David , Wenzel Jürgen J , Schmidt Barbara , Lampl Benedikt M J
Published: August 2021

Background

From a public health perspective, effective containment strategies for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) should be balanced with individual liberties.

Methods

We collected 79 respiratory samples from 59 patients monitored in an outpatient center or in the intensive care unit of the University Hospital Regensburg. We analyzed viral load by quantitative real-time polymerase chain reaction, viral antigen by point-of-care assay, time since onset of symptoms, and the presence of SARS-CoV-2 immunoglobulin G (IgG) antibodies in the context of virus isolation from respiratory specimens.

Results

The odds ratio for virus isolation increased 1.9-fold for each log10 level of SARS-CoV-2 RNA and 7.4-fold with detection of viral antigen, while it decreased 6.3-fold beyond 10 days of symptoms and 20.0-fold with the presence of SARS-CoV-2 antibodies. The latter was confirmed for B.1.1.7 strains. The positive predictive value for virus isolation was 60.0% for viral loads >107 RNA copies/mL and 50.0% for the presence of viral antigen. Symptom onset before 10 days and seroconversion predicted lack of infectivity with negative predictive values of 93.8% and 96.0%.

Conclusions

Our data support quarantining patients with high viral load and detection of viral antigen and lifting restrictive measures with increasing time to symptom onset and seroconversion. Delay of antibody formation may prolong infectivity.
Extended roles in primary care when physiotherapist-initiated referral to X-ray can save time and reduce costs
Authors: Peterson Gunnel , PortstrÖm Marie , Frick Jens
Published: August 2021

Objective

The objective of this study was to evaluate an extended role for the physiotherapist in primary care in referring patients to plain X-ray.

Methods

This prospective cohort study was set in a single region in Sweden. It included 20 physiotherapists who were educated in a 1-day training in performing referral to X-ray, along with 107 patients with musculoskeletal disorders who were referred to X-ray. We evaluated referral quality and patient and physiotherapist satisfaction and calculated healthcare and patient costs.

Results

All referrals fulfilled the basic requirements of quality, and 78% were classified as good, fulfilling all criteria. Both patients and physiotherapists were satisfied with the extended role for the physiotherapist that decreased the waiting time to diagnosis and to adequate treatment. Costs were reduced for patients (by €53/patient) and healthcare (by €6286.2/107 patients). The cost to visit a physician was twice that of a physiotherapist visit.

Conclusions

An extended role for physiotherapists in primary care in referring patients to X-ray was effective and safe for patients and reduced costs for patients and for healthcare. Physiotherapists in primary care were able to refer patients to X-ray after a 1 day of training, and the extended role freed up 45 min of physician time for each patient with a musculoskeletal disorder in need of an X-ray.
Mid- to long-term clinical outcomes of arthroscopic surgery for external snapping hip syndrome
Authors: Chu Chun-Ting , Hsu Huan , Tang Hao-Che , Chen Alvin Chao-Yu , Chan Yi-Sheng
Published: August 2021

This study evaluated the outcomes of arthroscopic surgery for the treatment of external snapping hip at 2- to 10-year follow-ups. Eighteen patients with refractory external snapping hip treated by arthroscopic surgery were enrolled in this prospective study. All patients underwent unsuccessful conservative treatment for more than 3 months before surgery. We made diamond-shaped defects on the iliotibial band and resected peripheral fibrosis tissues for iliotibial band release with an arthroscopic approach. The visual analog scale (VAS), modified Harris hip score and return to previous level of activity were evaluated as functional outcomes. In addition, residual discomfort or the presentation of complications was also investigated. The average follow up period was 7 years. The modified Harris hip score increased from 70.08 preoperatively to 93.14 postoperatively, and the VAS score decreased from 3.67 preoperatively to 1.17 2 weeks after the operation and declined to 0.33 at the last follow-up. Neither recurrence of snaps nor complications were recorded. Two patients complained of a tight sensation with tenderness after exertion. Our clinical outcomes were compatible with those of previous studies, and no long-term complications were noted, even with a relatively longer follow-up period than what was reported in previous studies. Arthroscopic surgery is a safe and effective treatment that can provide promising long-term clinical outcomes for patients with refractory external snapping hip.
Influence of Diet on Development and Survival of Thanatophilus rugosus (Coleoptera: Silphidae)
Authors: Qubaiová Jarin , Jakubec Pavel , Montoya-Molina Santiago , Novák Martin , Šuláková Hana
Published: August 2021

This study examined the effects of various diets on the development time and survival of the carrion beetle Thanatophilus rugosus (Fabricius, 1775). We attempted to find the best diet for rearing the species in laboratory conditions for entomological research and forensic purposes, and to further understand its feeding habits. The larval stages were monitored while feeding on three types of meat under a constant temperature. We discovered that the shortest development time in total was achieved in larvae fed with pork liver, followed closely by pork muscle. The longest development and lowest survival rates were observed when introducing a chicken diet. We were also able to identify specific stages during which the diet significantly affected the development.
Developing Physician Assistant Faculty Feedback Skills
Authors: Joyce Pauline
Published: August 2021

Investing time in mastering the feedback process is an important skill for all faculty. With physician assistant (PA) programs growing rapidly worldwide, faculty need to devote time to the education theory behind the feedback process. Within the clinical area, feedback is an everyday occurrence for PAs. However, ensuring that the process of giving feedback reaps dividends, ie, closes the feedback loop and ensures that learning and change of behavior have occurred, requires an understanding of what theories and models have already been tested with students. This article focuses on key principles of providing feedback and uses an example of a model of feedback, which highlights the challenges. An application to practice of the principles and model used as examples is provided, with a focus on self and peer feedback.
Acquisition and loss of CTX-M plasmids in Shigella species associated with MSM transmission in the UK
Authors: Locke Rebecca K. , Greig David R. , Jenkins Claire , Dallman Tim J. , Cowley Lauren A.
Published: August 2021

Shigellosis in men who have sex with men (MSM) is caused by multidrug resistant Shigellae, exhibiting resistance to antimicrobials including azithromycin, ciprofloxacin and more recently the third-generation cephalosporins. We sequenced four bla
CTX-M-27-positive MSM

Shigella

isolates (2018–20) using Oxford Nanopore Technologies; three

S. sonnei

(identified as two MSM clade 2, one MSM clade 5) and one

S. flexneri

3a, to explore AMR context. All

S. sonnei

isolates harboured Tn7/Int2 chromosomal integrons, whereas

S. flexneri

3a contained the

Shigella

Resistance Locus. All strains harboured IncFII pKSR100-like plasmids (67-83kbp); where present bla
CTX-M-27 was located on these plasmids flanked by IS26 and IS903B, however bla
CTX-M-27 was lost in

S. flexneri

3a during storage between Illumina and Nanopore sequencing. IncFII AMR regions were mosaic and likely reorganised by IS26; three of the four plasmids contained azithromycin-resistance genes erm(B) and mph(A) and one harboured the pKSR100 integron. Additionally, all

S. sonnei

isolates possessed a large IncB/O/K/Z plasmid, two of which carried aph(3’)-Ib/aph(6)-Id/sul2 and tet(A). Monitoring the transmission of mobile genetic elements with co-located AMR determinants is necessary to inform empirical treatment guidance and clinical management of MSM-associated shigellosis.