bluuebunny/crossref_metadata_2025 huggingface dataset:
Preparation and Repeated Repairability Evaluation of Sunflower Oil-Type Microencapsulated Filling Materials
Authors: Tan Xiaoyong , Zhang Jiupeng , Guo Dong , Sun Guoqing , Zhou Yingying , Zhang Wenwu
Published: September 2019

Cracks are the main challenges for asphalt pavement, which should be timely repaired. One of the most commonly used repairing methods is to fill the binding materials into cracks, but the repeated repairing ability is insufficient. The self-healing microcapsule technologies provide
the potentials for enhancing the repeated repairing ability of filling materials. Therefore, the microcapsule core material was selected from sunflower oil in this study, and the capsular wall material was selected from melamine-urea-formaldehyde resin, which was used to prepare the microcapsule
by using in-situ polymerization method. Three kinds of microcapsules with different particle sizes were prepared by adjusting the emulsifier dosage and core wall ratio. The microstructure, molecular structure, thermal stability, and dispersion features were further studied, and the
effects of microcapsules with different particle sizes on the repeated repairability of the filling materials were evaluated via the fatiguerepair-fatigue test. In addition, the traditional regenerative microcapsules were compared to determine the optimal particle size range for sunflower
oil microcapsules. According to the experimental research, it was thus concluded that the emulsion droplet size distribution was most concentrated when the emulsifier content was 0.7%; and when the core-wall ratio was 1.3:1, the microcapsules had uniform particle size and good dispersion effect.
When the microcapsule emulsification rate was 900 rpm and microcapsule content was 2%, then the repeated repair effect for the microcapsule crack filling materials was optimal. The sunflower oil type microcapsule therefore meets the filling temperature requirement for the filler.
Inverted Planar Perovskite Solar Cells Based on NiOx Nano Film with Enhanced Efficiency and Stability
Authors: Dai Kejie , Zhao Xuan
Published: September 2019

The organometal halide perovskite (OHP) materials have attracted much attention throughout the world due to their superb optoelectronic properties. Tremendous progress has been made in the OHP based solar cells with increased efficiency from 3.8% to 24.2% within the last decade, benefiting
from efforts in the photovoltaic field. However, all the OHP solar cells with highest efficient are based on a normal mesoporous structure with TiO2 at the bottom, which needs high temperature process. The inverted planar structure OHP solar cells based on PEDOT:PSS suffer from low efficiency
(lower than 15%) and inferior stability due to degradation of PEDOT:PSS in ambient air. Herein, we employed sol–gel method to fabricate a NiOx nano film as the hole transporting layer for inverted OHP solar cells. The device performance based on PEDOT:PSS and NiOx
were systematically investigated. It was found that the perovskite films on NiOx film had larger grain size and thus lower defects) density. The Capacitance–Voltage measurement indicated that the device based on NiOx exhibited larger built-in potential, which significantly
enhanced the open-circuit potential of the OHP solar cells. Furthermore, the solar cell based on NiOx nano film exhibited excellent stability compared with the PEDOT:PSS based device, due to robust property of NiOx in ambient air.
Influence of Scanning on Nano Crystalline β-Ti Alloys Fabricated by Selective Laser Melting and Their Applications in Biomedical Science
Authors: Yan Lamei , Yu Jianghong , Zhong Yuxing , Gu Yan , Ma Yunpeng , Li Wenxin , Yan Jia , Ge Yunyang , Yin Junhui , Luo Yuxiao , Mirzasadeghi A. , Yuan Youwei
Published: September 2019

The present study focuses on the microstructural and bioactive properties evolution in selective laser melting (SLM) β titanium alloys. We have applied cross-scan strategy for improving mechanical properties and lower elastic modulus of SLMed Ti–20Mg–5Ta alloys
which has been shown to be altering the microstructure and refining the grain size. The cross-scan strategy can refine the microstructure and induce various deformation textures in contrast to the conventional scan strategy. The microstructures of Ti–20Mg–5Ta alloys indicate that
the cross-scan strategy will yield the best mechanical properties and lower elastic modulus. The corrosion behavior of the Ti–20Mg–5Ta alloys was studied during immersion in an acellular simulated body fluid (SBF) at 37±0.50 °C for 28 days. Both the mechanical and bioactive
properties showed that the novel Ti–20Mg–5Ta alloys should be ideal for bone implants.
Second Step Aging on Nanosized Precipitates and Properties of Al–Zn–Mg–Cu–Cr Spray-Deposited Alloys
Authors: Gong Guo , Zhang Linying , Yuan Haijun , Jiang Jianbing , Ouyang Min , Xu Lijian
Published: September 2019

The effects of second step aging (T76, T74, T73) on nano-sized precipitates and properties of Al–Zn–Mg–Cu–Cr spray-deposited alloys were explored through tensile tester, impact testing machine, metallographic microscope (OM), eddy-current device, scanning electron
microscopy (SEM), twin-jet electro-polishing machine and transmission electron microscopy (TEM). Fine grain size (compared with as-deposited billet) and directional microstructures were obtained. T76 heat treatment of the alloy provided higher tensile strength, yield strength, impact toughness
and hardness which were 767 MPa, 708 MPa, 39.41 J/cm1/2 99.1 HRB, respectively in comparison with T74 and T73 samples. However, they provided lower elongation and electrical conductivity which were 7.6% and 31.1% IACS, respectively in comparison with T74 and T73 samples. This resulted
from the larger quantity and volume of tiny η′ precipitates that distribute homogeneously in matrix. However, coarse precipitates with increasing second step aging time (T74, T73) made wider grain boundary width and discontinuous η precipitates boosted conductivity of the
Al–Zn–Mg–Cu–Cr alloy. Furthermore, proportion of white precipitated phase in the matrix decreased slightly and volume became larger with increasing second step aging time.
Preparation of (S)-2-Phenylpropionic Acid by CaCl2/CMC Nanoparticles Immobilized Candida rugosa Lipase-Catalyzed Hydrolysis in Micro Aqueous Mixed Organic Solvent Systems
Authors: Liu Xueying , He Dongsheng , Li Xiaojuan , Deng Yan , Deng Jing , Li Ding , Ma Liang
Published: September 2019

Candida rugosa lipase was immobilized in this study using CaCl2/CMC nanoparticles that yielded a lipase loading capacity of 127 mg/g, with better thermal stability and activity of 91.8%. The hydrolysis of racemic 2-phenylpropionic acid isopropyl ester by free and immobilized
Candida rugosa lipase was investigated in the mixed organic-solvent composed of isooctane and methyl tert-butyl ether (9.5:0.5, V/V). The optimal conditions were 35 °C and pH 7.5 for free Candida rugosa lipase hydrolysis. We obtained (S)-2-phenylpropionic acid with
44.85% conversion, 95.75% enantiomeric excess and enantiomeric ratio of 112. The CaCl2/CMC nanoparticles immobilized Candida rugosa lipase possesses high enantioselectivity, with E = 237 at 40 °C and pH 7.5. It was efficiently reusable in four cycles and appropriately
enhanced enantioselectivity within 120–240.
Study of the Mechanical Properties and Toughening Mechanism of Nano-NbC Particles Toughened Si3N4-Based Ceramics
Authors: Tian Liang , Hou Qinglin , Wang Yingxia , Hou Yihui , Li Li
Published: September 2019

In this article, nano-NbC particles toughened Si3N4-based ceramics were prepared by injection moulding and their mechanical properties along with toughening mechanism were studied. An increase of nano-NbC content, gradually homogenizes microstructure of the Si3N4-based
ceramics along with increase in its density. However, the fracture toughness and flexural strength first increases and then decreases. The Si3N4-based ceramics demonstrate good comprehensive properties at the 15 wt% nano-NbC content and sintering temperature of 1550 °C
(where the density is 85.3%, the flexural strength is 845 MPa, and the fracture toughness is 9.3 MPa·m1/2), Backscattered electron imaging shows that nano-NbC particles can be well dispersed in the Si3N4 ceramic matrix by injection moulding and ceramics
are toughened by crack deflection and microcracking effects. It was also found that increasing sintering temperature makes the β-Si3N4 grain distribution more uniform by reducing the porosity.
Preparation of Nano-Silver-Containing Polyethylene Composite Film and Ag Ion Migration into Food-Simulants
Authors: Deng Jing , Ding Quan Ming , Li Wen , Wang Jian Hui , Liu Dong Min , Zeng Xiao Xi , Liu Xue Ying , Ma Liang , Deng Yan , Su Wei , Ye Bin
Published: September 2019

Nano-composite films were developed between silver nanoparticles (Ag NPs) and a low-density polyethylene (LDPE) using master batches by melt extruding and melt compounding. The Ag/PE composite film showed decreased gas permeability, moisture permeability coefficient, the tear strength,
the longitudinal and transverse elongation to that of commercial LDPE. Although stiffness increased at high Ag (40 ppm) concentration, but the longitudinal and transverse tensile strength enhance comparing with commercial PE. Light transmittance and haze were comparable. Both Nano-silver and
composite films are effective against Escherichia coli (E. coli). Antibacterial activity of nano-silver for E. coli was determined by diameter of the inhibition zone and the minimum inhibitory concentration of nano-silver is detected by tube double dilution method reaching
15.63 ppm. The composite films are effective inhibition of E. coli at concentrations of 40 ppm Ag nanoparticles. Moreover, Nano-silver migration occurs in composite film. One-side migration was conducted to detect under three food simulants (3% acetic acid, 50% ethanol and distilled
water) at three degree of temperature (25 °C, 40 °C and 70 °C) on different period of time (2, 4, 6, 8, 10 and 12 hours). These results indicated that the highest migration amount was obtained with 3% acetic acid following distilled water and finally 50% ethanol under same conditions.
The migration level is dependent upon time and temperature and high migration time and temperature can enhance migration level. These findings demonstrate that nano-silver-containing polyethylene composite film may have a great potential for developing antibacterial and acid food packaging
system.
Preparation and Properties of Nylon 6,6 Grafted Graphene Composites
Authors: Xiaoxiang Zhang , Jianxin He , Peng Wei , Xin Huang , Huimin Tian , Min Chen
Published: September 2019

Nylon 6,6 composite fiber containing grafted graphene (nylon 6,6-g-graphene) was prepared by nylon and graphene grafted with acyl chloride (graphene-COCl) through extrusion reaction. Graphene-COCl was prepared through acid-treated reacting, graphene with thionyl chloride functional
group. The chemical structure of nylon 6,6-g-graphene obtained using reactive extrusion technique was characterized using Fourier transform infrared spectrometer. It was found that this kind of composite fiber has the characteristics of less amount of graphene and excellent mechanical properties
and has certain application prospects. Nylon 6,6-g-graphene dispersed evenly in the Nylon composite. But pristine graphene exhibited aggregate structure when composite was produced by pristine graphene through reactive extrusion. The composite reinforcement was increased obviously with the
increase content of grafted graphene. After examined, the nylon/nylon 6,6-g-graphene with a certain content grafted graphene composite exhibited high level of reinforcement, and mechanical properties were improved.
Bioresorbable Mg-Based Metastable Nano-Alloys for Orthopedic Fixation Devices
Authors: Yan Lamei , Zhang Meiling , Wang Mihang , Guo Yuhui , Zhang Xiangquan , Xi Junhua , Yuan Youwei , Mirzasadeghi Alireza
Published: September 2019

This research has been accomplished using the advanced selective laser melting (SLM) technique as well as HIP post-treatment in order to improve mechanical properties and biocompatibility of Mg– Ca–Sr alloy. Through this research it becomes clearly noticeable that the Mg–1.5Ca–xSr
(x = 0.6, 2.1, 2.5) alloys with Sr exhibited better mechanical properties and corrosion potentials. This is more particular with the Mg–1.5Ca–2.5Sr alloy after HIP post-treatment allowing it to provide a desired combination of degradation and mechanical behavior for orthopedic
fracture fixation during a desired treatment period. In vivo trials, there was a clear indication and exhibition that this Mg–1.5Ca–2.5Sr alloy screw can completely dissolve in miniature pig’s body which leads to an acceleration in growth of bone tissues. Mg–Ca–Sr
alloy proved potential candidate for use in orthopedic fixation devices through Our results concluded that Mg–Ca–Sr alloy are potential candidate for use in orthopedic fixation devices through mechanical strength and biocompatibility evaluations (in vitro or In vivo).
Ribonuclease H Enzyme Activity Detection Based on Hybridization Chain Reaction Amplification and Graphene Oxide Nanosheets Fluorescence Quenching
Authors: Liu Cun , Tang Ying , Chen Yao , Deng Jing , Li Wen , Tang Jianxin
Published: September 2019

Ribonuclease H (RNase H) plays key roles in HIV virus replication process and can be used as an important target for anti-AIDS drugs screening. Therefore, we constructed a fluorescent nanosensor based on signal amplification of hybridization chain reaction (HCR) and fluorescence quenching
of graphene oxide (GO) nanosheets. The nanosensor provided highly sensitive and selective platform for RNase H activity detection. This method also exhibited a good linear relationship in the range of 0.001–5 U/mL, and the detection limit was 0.0007 U/mL. Our results suggested that the
developed system is a promising platform for monitoring the RNase H activity, showing great potential in the biomedical studies and drugs screening.
Synthesis of a Molecularly Imprinted Polymer on NH2-MIL-101(Cr) for Specific Recognition of Diclofenac Sodium
Authors: Wang Yulin , Qiu Xiuzhen , Li Yangyang , Guo Huishi , Lu Wenguan , Nie Libo
Published: September 2019

A novel molecularly imprinted polymer material based on the metal-organic framework NH2-MIL-101(Cr) (MOF-MIP) was prepared. The synthesized MOF-MIP was characterized by IR, XRD, SEM and N2 absorption. The characterization results displayed that the MOF-MIP which exhibited
an octahedral shape had good dispersibility, good thermal stability and a high surface area. Subsequently, the adsorption behavior of MOF-MIP to diclofenac sodium (DS) in aqueous solution was examined. A series of adsorption experiments demonstrated that the MOF-MIP had high transfer mass
rates and high sensitivity and selectivity for DS. Then the MOF-MIP was used as the adsorbent of dispersive micro-solid phase extraction (DMSPE) for the detection of DS in urine. Under optimum conditions, the average recovery of DS ranged from 88.3 to 101.6% with RSD of 5.6%. The described
method provides a rapid route for determination of DS in human urine.
Synthesis and Inkjet Printing of NaYF4:Ln3+@NaYF4 Core–Shell Nanoparticles with Enhanced Upconversion Fluorescence for Anti-Counterfeiting Applications
Authors: Song Ya , Gong Guo , Du Jingjing , Xie Shaowen , Ouyang Min , Feng Yahui , Xu Jianxiong , Xu Lijian
Published: September 2019

Recently, lanthanide-doped upconversion luminescent materials have showed great potential in optical data storage, information encryption and anti-counterfeiting. However, the low upconversion luminescence still limited their applications. In this work, we fabricated RGB NaYF4:Ln3+@NaYF4
core–shell nanoparticles (CSNPs) with enhanced upconversion luminescence by coating an inert NaYF4 shell onto NaYF4:Ln3+ core nanoparticles via thermal decomposition method. The effect of increased shell temperature and addition of shell precursors on
crystal phase, morphology and luminescent property of the synthesized CSNPs were systematically investigated. It was demonstrated that high shell growing temperature facilitated the formation of pure β-NaYF4 CSNPs. Upon increasing amount of shell precursors, the morphologies
of hexagonal phase NaYF4 CSNPs changed from nanorod to nanocube and showed different luminescent properties. Pure hexagonal phase NaYF4 CSNPs with highest upconversion luminescence of about 15 times higher than NaYF4:Ln3+ core nanoparticles can be
prepared at 310 °C with the addition of shell precursors at 3 mmol. Moreover, three-primary-color (RGB) CSNPs with enhanced upconversion luminescence were successfully prepared by changing the doping pair of lanthanide ions in core. The synthesized RGB CSNPs were fabricated into environment
friendly luminescent ink by sequential surface modification by PAA ligand and dispersing in mixture solvent of ethanol, water and glycerol. Comparative results showed that the fluorescence enhanced RGB CSNPs inks were more suitable for inkjet printing of multicolored, complex and high resolution
luminescent anti-counterfeiting patterns on paper substrates.
Rapid Detected and Diagnostic Assessment Vacuolating Cytotoxin A (vacA) Gene of Helicobacter pylori by Loop-Mediated Isothermal Amplification (LAMP)
Authors: Zheng Yingying , Wu Jiali , Yang Yuan , Liu Mengqiong , Li Dongdong
Published: September 2019

The loop-mediated isothermal amplification (LAMP) assay as efficient and convenient detection method was applied to detect the vacuolating cytotoxin A (vacA) gene of Helicobacter pylori (H. pylori). The extracted genomic DNA of H. pylori, which was purified through
magnetic nanoparticles (MNPs), was amplified through the LAMP reaction using designed primers. The effect of LAMP detected on H. pylori vacA gene was evaluated through agarose gel electrophoresis in a gel imaging system and fluorescence-intensity analysis after addition of fluorescent
dye. 11 pathogenic bacterial strains of different species were found to be negative for vacA, while only a single positive result was obtained for H. pylori. The minimum detection limit of the vacA gene was established as 100 fg. We used the primers with specificity and
sensitivity, which were designed by the specificity analysis and sensitivity analysis system. Once developed, the LAMP assay was be used to the detection of the vacA gene in the gastric juice of patients. In conclusion, the LAMP assay is an efficient and fast tool for detection of the
H. pylori vacA gene, and also for direct detection of the vacA gene in the gastric juice of patients, with high sensitivity and specificity. Most importantly, the proposed detection method shows promising potential for clinical application in the future, where it can greatly
reduce the difficulty of detection and also shorten detection times.
Mechanical Gripper Design and Force Analysis of Microplates for Automated High-Throughput Nucleic Acid Detection System
Authors: Wang Chao , Guo Zhukang , Zhu He , He Nongyue , Chen Zhu , Wang Zunliang
Published: September 2019

In the automated high-throughput nucleic acid detection system, we need to grip and transfer consumables frequently when carrying out multichannel nucleic acid detection. In order to ensure the efficiency of experiments and solve problems of the deflection and drop when transferring
microplates, we design a self-locking mechanical gripper which consists of a rotary positioning module and a gripping module. The absolute position encoder fixed on the top of the stepper motor can collect the position data of the mechanical gripper in real time and send them to the master
control board based on STM32 for processing, which ensures the accuracy of the movement of the mechanical gripper. We used SolidWorks to build models of the mechanical gripper and different microplates, and we carried on finite element analysis of microplates to find the suitable gripping
position. Through the force analysis, we obtained the pressure distribution and the deformation of different microplates, and defined the effective gripping areas, which is important to the grip and transfer of microplates.
Design and Implementation of Polymerase Chain Reaction Device for Aptamers Selection of Tumor Cells
Authors: Wang Chao , Meng Fan , Huang Yanping , He Nongyue , Chen Zhu
Published: September 2019

Nucleic acid aptamers are a kind of one-dimensional biological nanomaterials and have found many applications. This paper designed and implemented a polymerase chain reaction (PCR) amplification device with a reaction volume of 500 μL, which can be used for the amplification
of nucleic acid aptamers of tumor cells in the aptamer selection. This device mainly includes a control module, a temperature measuring module, a PCR amplification tube, a metal tank module, a liquid crystal display (LCD) and operation module and a cooling module. The new PCR amplification
chamber is matched with the designed metal tank to ensure the temperature uniformity of the PCR amplification solution. The control module based on the STM32F103RCT6 manages the workflow of the entire device. The PCR amplification chamber and PT100 sensors on the metal tank formed a closed-loop
feedback system, and the incremental proportional-integral-derivative (PID) algorithm was used to achieve the precise temperature control. In addition, we introduced the Smith predictive compensation algorithm to solve the temperature hysteresis problem of the PCR amplification chamber. The
experimental results showed that the PCR device can meet the requirements for the nucleic acid aptamer selection of tumor cells. The device can also be used in other experiments with large-volume PCR amplification.
Novel Magnetic Nanocluster@Graphene Oxide Composites for Potential Application in Environmental Adsorption
Authors: Hu Zhongliang , Zhang Xiaojing , Cui Houquan , Li Zhaohui
Published: September 2019

Graphene-oxide-wrapped magnetic Fe3O4 nanocluster (NC) composites (MC@GO) were prepared and their characteristics were analyzed by multiple characterization methods. Results indicated that the magnetic NCs (~400 nm in size) were composed of numerous Fe3O4
monocrystalline particles (30–50 nm in size) and MC@GO had stable structure, high saturation magnetization (61 emu/g) and specific surface area of 112.5 m2/g. The magnetic NCs were integrally and tightly encapsulated in the composites by silk-like GO sheets via electrostatic
interaction. The formation mechanism for MC@GO is also discussed in detail herein. Fe3+ was reduced by ethylene glycol in the adopted synthesis scheme, to generate Fe3O4 monocrystalline particles that aggregated to form Fe3O4 NCs with
rough surfaces. Subsequent SiO2 coating and positive charge introduction caused the GO sheets to firmly wrap around the magnetic NCs, resulting in novel GO wrapped magnetic NC composites. The Fe3O4 NCs contributed much to structure amelioration and performance enhancement
of the final GO composites. The rough surfaces of Fe3O4 NCs were beneficial for the SiO2 coating and final wrapping of GO sheets. The good magnetic property and beneficial structure of MC@GO make it an ideal adsorbent, which was demonstrated in the current study using
methylene blue (MB) as a model adsorbate. The maximum MB adsorption capacity for MC@GO reached 105.5 mg/g. This is the first study on GO-wrapped Fe3O4 NC composites and their potential use for environmental adsorption. Furthermore, this study provides a method for developing
GO wrapped magnetic particle composites by tailoring the magnetic precursor.
Facile Synthesis of Tremella-Like Li3V2(PO4)3/C Composite Cathode Materials Based on Oroxylum for Use in Lithium-Ion Batteries
Authors: Liu Zhen , Zhou Wei , Zeng Guilin , Zhang Yuling , Wu Zebin , Chen Han
Published: September 2019

Oroxylum as a traditional Chinese medicine, was used as a green and novel bio-template to synthesize tremella-like Li3V2(PO4)3/C composite (LVPC) cathode materials by adopting a facile immersion method. The microstructures were analyzed by
X-ray diffraction analysis, scanning electron microscopy, and transmission electron microscopy. The electrochemical properties were investigated by galvanostatic charge–discharge experiments. The LVPC revealed specific capacity of 95 mAh·g-1 at 1 C rate within potential
range of 3.0–4.3 V. After 100 cycles at 0.2 C, the retention of discharge capacity was 96%. The modified electrochemical performance is mainly resulted from the distinct tremella-like structure.
Automated Driving System Collisions: Early Lessons
Authors: Biever Wayne , Angell Linda , Seaman Sean
Published: September 2019

Objective

This research evaluated Automated Driving Systems (ADSs) involved collisions to identify factors relevant to future ADS research and development.

Background

Rapidly developing ADSs promise improved safety, among other benefits. Properly applied collision research can inform ADS development, to minimize future collisions. Errors and failures that result in collisions come from sources including the system, ADS operators, and external factors including other drivers. Partially automated systems incorporate new equipment and procedures creating new sources of human error. Fully autonomous systems represent a new class of drivers that interact in unique ways.

Method

ADS collision reports from the California Department of Motor Vehicles and the National Transportation Safety Board were collected. An expert in human factors and collision investigation analyzed and categorized the crashes while extracting common factors.

Results

ADS vehicles were never at fault but were often affected from the rear during braking, turning, and gap acceptance maneuvers. Side impacts to ADS vehicles were related to passing vehicles and lane keeping behaviors. Unique incidents also provided additional insights. ADS collision rates cannot yet be determined with confidence.

Conclusion

Conflicts that lead to collision-involvement with ADSs may be caused by differences between ADS and human driving behavior. Conservative ADS behavior may violate the expectations of other nearby human road users.

Application

The findings from this work help inform the future development of ADS, as well as potentially the testing of ADS and the formation of policy to guide their future deployment.
Retarding the decay of temperature in the air flow field during the melt blowing process using a thermal insulation tube
Authors: Hao Xibo , Yang Ying , Zeng Yongchun
Published: September 2019

During melt blowing, most of the polymer jet attenuation occurs in the area within 2 cm from the die, due to the rapid decrease of polymer jet temperature. Therefore, keeping the polymer jet temperature above melting point for a longer time is beneficial for its attenuation. Here, a thermal insulation tube with heating ability was introduced into the air flow field during the melt blowing process. The computational fluid dynamics technique was employed to investigate the effects of the thermal insulation tube on the air flow field. It was found that the thermal insulation tube has enhancing effects on the temperature, velocity, and turbulence kinetic energy of the air flow field. Experiments were conducted to examine the fiber diameters of the final nonwovens, the results of which indicates that a die with a thermal insulation tube can achieve a higher polymer jet attenuation and that the heating effect can further enhance the attenuation. Based on the computational fluid dynamics technique, the effects of the tube diameter and length on the temperature, velocity, and turbulence kinetic energy of the air flow field were investigated.
Surgical glove use for specimen removal in laparoscopy, the cheapest available: a prospective study
Authors: Islam Shariful , Bheem Vinoo , Maughn Anthony , Harnarayan Patrick , Dan Dilip , Naraynsingh Vijay
Published: September 2019

Despite the proven benefits of laparoscopic surgery, it is indeed very costly. The aim of our study was to show an effective way to reduce one of the costs. Between January 2012 and December 2018, we used sterile unpowdered latex-free surgical gloves for specimen retrieval in 243 selected cases of laparoscopic cholecystectomy and appendectomy. The mean retrieval time was 6.7 ± 3.6 min. All procedures were performed safely. Minor wound infection was noted in three patients but there was no case of port site hernia in our series. We conclude that specimen retrieval using sterile, unpowdered, latex-free surgical gloves is safe, effective and cheap. No special additional preparation is required.
Optic neuritis following anti-rabies vaccine
Authors: Agarwal Ayush , Garg Divyani , Goyal Vinay , Pandit Awadh K , Srivastava Achal K , Srivastava MV Padma
Published: September 2019

Neurological complications related to anti-rabies vaccine are uncommon. The involvement of the optic nerve is extremely rare. It has been occasionally reported after Semple’s vaccine administration due to the presence of highly antigenic sheep brain tissue in the vaccine. To our knowledge, this is the first case report of optic neuritis after chick embryo-derived anti-rabies vaccine.
Liquid–liquid gravity displacement in a vertical fracture during drilling: Experimental study and mathematical model
Authors: Xiao Dong , Meng Yingfeng , Zhao Xiangyang , Li Gao , Xu Jiaxin
Published: September 2019

Gravity displacement often occurs when drilling a vertical fractured formation, causing a downhole complexity with risk of blowout and reservoir damage, well control difficulty, drilling cycle prolongation, and increased costs. Based on an experimental device created for simulating the gravity displacement, various factors affecting the displacement quantity were quantitatively evaluated by simulating the fracture width, asphalt viscosity, drilling fluid density, and viscosity under different working conditions, and a liquid–liquid displacement law was obtained. Using the theories of rock mechanics, fluid mechanics, and seepage mechanics, based on conformal mapping, as well as a fracture-pore double substrate fluid flow model, we established a steady-state mathematical model of fractured formation liquid–liquid gravity displacement by optimizing the shape factors and using a combination of gravity displacement experiments to verify the feasibility of the mathematical model. We analyzed the influence of drilling fluid density, fracture height and length, and asphalt viscosity on displacement rate, and obtained the corresponding laws. The results show that when the oil–fluid interface is stable, the fracture width is the most important factor affecting the gravity displacement, and plugging is the most effective means of managing gravity displacement.
Interview with Vicki Kirby
Authors: McLoughlin Daniel
Published: September 2019

In this interview, Vicki Kirby discusses her research into the relationship between nature and culture, focusing in particular on her recent edited collection, What If Culture Was Nature All Along? The volume appears in the ‘New Materialisms’ series, and so the interview begins by situating the collection with respect to the recent materialist turn in social theory. Kirby discusses the influence of deconstruction on her thought, and the way that she draws upon Derrida to think through recent research in the life sciences and its implications for understanding the relationship between matter, life, and communication. She also goes into the political implications of her work and the relationship between biopolitics and biodeconstruction.
Increasing cerebral blood flow improves cognition into late stages in Alzheimer’s disease mice
Authors: Bracko Oliver , Njiru Brendah N , Swallow Madisen , Ali Muhammad , Haft-Javaherian Mohammad , Schaffer Chris B
Published: September 2019

Alzheimer’s disease is associated with a 20–30% reduction in cerebral blood flow. In the APP/PS1 mouse model of Alzheimer’s disease, inhibiting neutrophil adhesion using an antibody against the neutrophil specific protein Ly6G was recently shown to drive rapid improvements in cerebral blood flow that was accompanied by an improvement in performance on short-term memory tasks. Here, in a longitudinal aging study, we assessed how far into disease development a single injection of anti-Ly6G treatment can acutely improve short-term memory function. We found that APP/PS1 mice as old as 15–16 months had improved performance on the object replacement and Y-maze tests of spatial and working short-term memory, measured at one day after anti-Ly6G treatment. APP/PS1 mice at 17–18 months of age or older did not show acute improvements in cognitive performance, although we did find that capillary stalls were still reduced and cerebral blood flow was still increased by 17% in 21–22-months-old APP/PS1 mice given anti-Ly6G antibody. These data add to the growing body of evidence suggesting that cerebral blood flow reductions are an important contributing factor to the cognitive dysfunction associated with neurodegenerative disease. Thus, interfering with neutrophil adhesion could be a new therapeutic approach for Alzheimer’s disease.
Mannose-binding lectin has a direct deleterious effect on ischemic brain microvascular endothelial cells
Authors: Neglia Laura , Fumagalli Stefano , Orsini Franca , Zanetti Adriana , Perego Carlo , De Simoni Maria-Grazia
Published: September 2019

Mannose-binding lectin (MBL), an initiator of the lectin pathway, is detrimental in ischemic stroke. MBL deposition on the ischemic endothelium indicates the beginning of its actions, but downstream mechanisms are not clear yet.

We investigated MBL interactions with the ischemic endothelium by exposing human brain microvascular endothelial cells (hBMECs) to protocols of ischemia. Cells were exposed to hypoxia or oxygen–glucose deprivation (OGD), and re-oxygenated with human serum (HS) or recombinant MBL (rhMBL). Hypoxic hBMECs re-oxygenated with HS showed increased complement system activation (C3c deposition, +59%) and MBL deposition (+93%) than normoxic cells. Super-resolution microscopy showed MBL internalization in hypoxic cells and altered cytoskeletal organization, indicating a potential MBL action on the endothelial structure. To isolate MBL effect, hBMECs were re-oxygenated with rhMBL after hypoxia/OGD. In both conditions, MBL reduced viability (hypoxia: −25%, OGD: −34%) compared to conditions without MBL, showing a direct toxic effect. Ischemic cells also showed greater MBL deposition (hypoxia: +143%, OGD: +126%) than normoxic cells. These results were confirmed with primary hBMECs exposed to OGD (increased MBL-induced cell death: +226%, and MBL deposition: +104%). The present findings demonstrate that MBL can exert a direct deleterious effect on ischemic brain endothelial cells in vitro, independently from complement activation.
Delayed clearance of cerebrospinal fluid tracer from choroid plexus in idiopathic normal pressure hydrocephalus
Authors: Eide Per Kristian , Valnes Lars Magnus , Pripp Are Hugo , Mardal Kent-Andre , Ringstad Geir
Published: September 2019

Impaired clearance of amyloid-β from choroid plexus is one proposed mechanism behind amyloid deposition in Alzheimer's disease. The present study examined whether clearance from choroid plexus of a cerebrospinal fluid tracer, serving as a surrogate marker of a metabolic waste product, is altered in idiopathic normal pressure hydrocephalus (iNPH), one sub-type of dementia. In a prospective observational study of close to healthy individuals (reference cohort; REF) and individuals with iNPH, we performed standardized T1-weighted magnetic resonance imaging scans before and through 24 h after intrathecal administration of a cerebrospinal fluid tracer (the magnetic resonance imaging contrast agent gadobutrol). Changes in normalized T1 signal within the choroid plexus and cerebrospinal fluid of lateral ventricles were quantified using FreeSurfer. The normalized T1 signal increased to maximum within choroid plexus and cerebrospinal fluid of lateral ventricles 6–9 h after intrathecal gadobutrol in both the REF and iNPH cohorts (enrichment phase). Peak difference in normalized T1 signals between REF and iNPH individuals occurred after 24 h (clearance phase). The results gave evidence for gadobutrol resorption from cerebrospinal fluid by choroid plexus, but with delay in iNPH patients. Whether choroid plexus has a role in iNPH pathogenesis in terms of delayed clearance of amyloid-β remains to be shown.
Comparing amide proton transfer imaging with dynamic susceptibility contrast-enhanced perfusion in predicting histological grades of gliomas: a meta-analysis
Authors: Song Qingxu , Zhang Chencheng , Chen Xin , Cheng Yufeng
Published: September 2019

Background

As a subtype of chemical exchange saturation transfer imaging without contrast agent administration, amide proton transfer (APT) imaging has demonstrated the potential for differentiating the histologic grades of gliomas. Dynamic susceptibility contrast-enhanced perfusion, a perfusion-weighted imaging technique, is a well-established technique in grading gliomas.

Purpose

To compare the ability of amide proton transfer and dynamic susceptibility contrast-enhanced imaging for predicting the grades of gliomas.

Material and Methods

A comprehensive literature search was performed independently by two observers to identify articles about the diagnostic performance of amide proton transfer and dynamic susceptibility contrast-enhanced perfusion in predicting the grade of gliomas. Summary estimates of diagnostic accuracy were obtained by using a random-effects model.

Results

Of 179 studies identified, 23 studies were included the analysis. Eight studies evaluated amide proton transfer and 16 studies evaluated dynamic susceptibility contrast-enhanced perfusion with the parameter rCBV. The pooled sensitivities and specificities of each study’s best performing parameter were 88% (95% confidence interval [CI] 74–95) and 89% (95% CI 78–95) for amide proton transfer, and 95% (95% CI 87–98), 88% (95% CI 81–93) for perfusion-weighted imaging–dynamic susceptibility contrast-enhanced perfusion, respectively. The pooled sensitivities and specificities for grading gliomas using the two most commonly evaluated parameters, were 92% (95% CI 80–97) and 90% (95% CI 75–96) for APTmax, and 97% (95% CI 91–99) and 87% (95% CI 80–92) for rCBVmax, respectively.

Conclusion

Considering the similar performance of APT and dynamic susceptibility contrast-enhanced (DSC) in predicting glioma grade, the former method appears preferable since it needs no contrast agent.
Developmental coordination disorder in UK children aged 6–18 years: Estimating the cost
Authors: Cleaton Mary Ann Megan , Lorgelly Paula Kate , Kirby Amanda
Published: September 2019

Introduction

Developmental coordination disorder is a neurodevelopmental disorder affecting motor ability, with an estimated prevalence of between 2% and 6% in school-aged children. It is associated with considerable psychosocial impact. However, the financial cost this poses to families and society has never been assessed. We aimed to estimate the direct, indirect and out-of-pocket costs associated with developmental coordination disorder in United Kingdom school-aged children in the 6 months prior to our survey.

Method

Parents/guardians answered an online questionnaire adapted from the Client Service Receipt Inventory.

Results

Mean direct healthcare costs were approximately £700 in the 6 months prior to the survey. Almost all children were in mainstream education, but many received additional support. Among children who received therapy, the average indirect cost was £574 in the 6 months prior to the survey. However, this did not include changes to employment made to accommodate caring for the child. Notably, respondents commented that they frequently struggled to access services for their children. Thus, these figures may be a marked underestimation of true need.

Conclusion

This study represents the first cost-of-illness study for developmental coordination disorder. It demonstrates that developmental coordination disorder incurs a significant cost to society but particularly to families. Improvements to diagnostic pathways and post-diagnosis service provision are much needed.
Umbilical arterial Doppler ultrasonography predicts late pregnancy outcomes in patients with lupus nephritis: a multicenter study from southern China
Authors: Chen D , Yuan S , Lao M , Zhan Y , Xu H , Liang L , Cai X , Wang X , Zhan Z
Published: September 2019

Objectives

To investigate the fetal adverse pregnancy outcomes (APOs) and the predictive value of umbilical arterial Doppler ultrasonography in the third trimester in pregnant women with lupus nephritis (LN).

Methods

A retrospective cohort study enrolling 203 LN patients from 2007 to 2017 was performed. Ultrasonic parameters were recorded.

Results

Fetal APOs occurred in 103 patients (103/203, 50.7%). Sixty-six pregnancies (66/203, 32.5%) ended with preterm births. The incidence rate of intrauterine growth restriction (IUGR) was 18.2% (37/203). Fetal distress was noted in 23 pregnancies (23/203, 11.3%). All the Doppler parameters elevated in patients with IUGR, fetal distress, and composite conditions. Resistance index (RI) indicated the highest risk of IUGR and composite APOs. The cutoff values were 0.66 and 0.67, respectively. Sensitivities were 51.4% and 33.7%, and specificities were 87.4% and 92.1%. Peak velocity of the umbilical arteries at end-systole (Vmax, abbreviated as S) to that at end-diastole (Vmin, abbreviated as D) (S/D) ratio was also a best predictor for IUGR, with the optimal cutoff value of 2.88. Sensitivity and specificity were comparable with RI. Pulsatility index (PI) over 0.84 was an ideal indicator for fetal distress with an optimal combination of sensitivity (89.5%) and specificity (51.6%).

Conclusions

Fetal complications were frequent in patients with LN. Umbilical arterial Doppler ultrasonography was a useful measure to predict late IUGR, fetal distress, and the composite APOs.
The impact of corticosteroid use during anti-PD1 treatment
Authors: Pan Eva Y , Merl Man Yee , Lin Katherine
Published: September 2019

Background

The advent of anti-PD1 therapy for cancer treatment has led to improvements in response rates and overall survival. However, anti-PD1 therapy has the potential to cause immune-related adverse events (irAEs), which can be treated with corticosteroids if severe. The clinical implications of concomitant immunotherapy and systemic steroids remain unclear, as short courses of steroids do not significantly suppress T-cell function. The primary objective of this study is to determine if the use of concomitant steroids impacts the efficacy of anti-PD1 therapy.

Methods

This retrospective, single-center study reviewed adult patients who received at least four cycles of nivolumab or pembrolizumab for the treatment of melanoma, non-small cell lung cancer (NSCLC), or renal cell carcinoma from November 2014 to February 2016. Patients who received steroids (prednisone equivalent >10 mg) during anti-PD1 therapy were divided into two main cohorts based on the duration of steroid administration of ≤2 weeks or >2 weeks. Time to disease progression, overall response, and overall survival were assessed.

Results

Twenty-seven of 55 patients (13 melanoma, 11 NSCLC, 3 renal cell carcinoma) required steroids during anti-PD1 therapy. In patients who received steroids, median time to disease progression was 5.6 months for melanoma, 5.8 for NSCLC, and 2.0 for renal cell carcinoma. The overall response rate (ORR) was 3/13 (23%) for melanoma, 6/11 (54%) for NSCLC, and 1/3 (33%) for renal cell carcinoma. Median overall survival was 11.9 months for melanoma, 9.9 for NSCLC, and not reached for renal cell carcinoma. Thirteen patients who had received steroids expired; 11 of these patients had received prednisone >10 mg/day for >2 weeks.

Conclusion

High-dose steroids for long durations during anti-PD1 therapy may be associated with poorer survival outcomes.
Playing with frames of reference in veneration rituals: Fractal dynamics in encounters with a Muslim saint
Authors: Kreinath Jens
Published: September 2019

Paradigmatic shifts in anthropological theory shape the ways in which play and ritual are conceptualized. By demarcating these shifts, the argument is made that an analysis of both play and ritual must start with the possibility of choice as distributed among participants who engage in play and ritual as forms of social practice. Taking the dynamics of framing in play and ritual and the patterns emerging in social interaction as a point of departure, the configuration of ‘fractal dynamics’ is introduced to relate play and rituals as emerging through recursive processes of framing social interaction. Based on rituals of saint veneration among Arab Alawites in southernmost Turkey, it is argued that not only are forms of ritual interaction among devotees at pilgrimage sites playful but also that ritual interactions of devotees with the saint are a form of existential play of chance and disguise. By taking into account the myth and social cosmology that institutes such rituals of veneration and interaction with the saint, it is concluded that these rituals of veneration and interaction with the saint as a non-human agent play with frames of reference. This is done in similar ways, as when the saint acts as a trickster or symbolic type and is perceived by devotees as playing with their perception through disguise and simulation. The reconfiguration of play and ritual through ‘fractal dynamics’ does not only explain the changing dynamics of social configurations in religious interactions with non-human agents, but it also helps to account for probability and choice—and simulation and disguise—in social situations that border the religious and mundane.
Dynamics of movement: Intensity, ritualized play and the cosmology of kinship relations in Northeast Brazil
Authors: Shapiro Matan
Published: September 2019

Relations between play and ritual are notoriously problematic. While play tends to produce doubt, uncertainty and paradox, ritual instead clarifies, authenticates and refines the moral order. Focusing ethnographically on a celebration for the Divine Holy Spirit ( Divino Espírito Santo) in the Brazilian state of Maranhão, in this article I nonetheless move away from this common juxtaposition of ritual and play as mutually exclusive conceptual frameworks. I argue that we can instead imagine play and ritual as dynamic, processual experiences, which frequently merge when they are enacted together in highly symbolic public events. Seen in this light, ritual and play do not necessarily differ as rigid, predefined, conceptual frames, but rather as experiences that unfold in different forms: the experiential dynamic of play-scenarios is felt as horizontal deregulation, while the experiential dynamic of rituals converges towards and linear hierarchization. I consequently suggest more broadly that such dynamic terms as ‘pulsation’, ‘intensity’ and ‘rhythm’ better explicate the enduring social effects of public events in which the unequivocal and the ambiguous incessantly reconstitute each other.