bluuebunny/crossref_metadata_2025 huggingface dataset:
Application Research of Orthogonal Analysis for Components Selection of Heat-Resistant Concrete
Authors: Xu Xing Wei , Yao Ji
Published: August 2014

Combined with the heat-resistant concrete needed for a company combustor, based on the availability of local raw materials, the orthogonal test was used, then by the variance analysis and range analysis, the components of the heat-resistant concrete which could meet the technical requirements of the project were selected. Engineering application results showed: the components of the concrete could meet technical indicators for the engineering application, and effectively reduced the cost of production of heat-resistant concrete.
Control the Pollution of Pig Farm’s Manure Wastewater and Resource to Cultivate Microalgae
Authors: Huang Xue Ping , Sheng Guo Jun , Chen Chun Li , Ji Yong , Liu Fan Qi
Published: August 2014

At present, the pig manure wastewater pollution and adverse effects on the environment are increasingly prominent in China. The conventional treatments are often restricted by many factors which influence the treatment effect. Utilize the piggery wastewater resource to cultivate energy microalgae for biodiesel preparation, not only can reduce the production cost of biodiesel and ease the energy crisis, but can achieve the purpose of wastewater purification. In this paper, the authors used a pig farm’s wastewater to cultivateChlorella vulgaris. Experiments results show thatChlorella vulgarishas strong stain resistant and impact resistant ability, it can grow advantageously in the swine wastewater environment.
A New Method for Testing Formability in Sheet Metal Forming at Biaxial Tensile State
Authors: Lee Rong Shean , Chien Ta Wei
Published: August 2014

This paper presents a new method concerning testing formability in sheet metal forming, especially focuses on clarifying the divergence of the experiment and a variety of theoretical predictions on biaxial tensile state. Up to now, there are many different fracture criteria appeared. All researches have presented their experimental data which could justify the criterion they presented. However, the experimental results and predictions in the first quadrant of the forming limit diagram (FLD) often diverge. Today, limiting dome height test is commonly used for FLD experiment, but specimens are rubbed and bended during the test, both influencing the experimental results.In order to provide for convincible experimental data, this paper presents a new experimental method to establish the first quadrant of FLD. In this method, cruciform biaxial tensile specimen and biaxial tensile apparatus have been developed. The proposed specimen has the feature of thickness reduction and contour design to ensure the fracture location is in the central region, so that accurate biaxial tensile state can be obtained. Through this method, there is an opportunity to obtain the whole FLD using uniaxial tensile testing machine, which is a low-cost alternative in compared with limiting dome height test. Besides, the experimental results can be utilized to clarify the divergence between various theoretical predictions and experimental results in the first quadrant of the FLD.
Prediction of Fracture Strains for DP980 Steel Sheets Using a Modified Lou–Huh Ductile Fracture Criterion
Authors: Park Namsu , Huh Hoon
Published: August 2014

This paper is concerned with the prediction of fracture strains for DP980 steel sheets using a modified Lou–Huh ductile fracture criterion. The usage of DP980 steel is significantly increasing in the automotive industry for weight reduction, enhancement of crashworthiness and safety of car body. The material behavior of AHSS show unpredictable and sudden fracture during sheet metal forming process. A modified Lou–Huh ductile fracture criterion is utilized to predict the formability of AHSS because the conventional FLD constructed based on necking is unable to evaluate the formability of AHSS. Fracture loci were extracted from 3D fracture envelopes by assuming the plane stress condition to evaluate equivalent plastic strain up to the point of fracture at a wide range of loading paths. Three different types of specimens such as pure shear, dog-bone and plane strain grooved specimens were used for tensile tests to construct 3D fracture envelopes of DP980. Fracture strain of each loading path was evaluated to show that there is little deviation between predicted fracture strains and experimentally acquired ones. From the comparison, it is concluded that the 3D fracture envelopes can accurately predict the onset of the fracture of DP980 steel sheets in complicated loading conditions including the pure shear condition.
Development of Rotary Laser Dieless Drawing Apparatus for Metal Microtubes
Authors: Furushima Tsuyoshi , Imagawa Yusuke , Furusawa Shusaku , Manabe Kenichi
Published: August 2014

We develop new drawing technologies of rotary laser dieless drawing for the fabrication of micro-tubes without the need for tools such as dies, plugs and mandrels. A rotary laser dieless drawing apparatus with local heating using a laser irradiated from one direction as the heating source has been focused on for the fabrication of micro-tubes. In this study, a dieless drawing with a semiconductor laser setup with power of 30W is designed and developed. A workpieces was rotated about a tensile axis by rotary stage with chucks for circumferential uniform temperature distribution. A tube of stainless steel SUS304, with an outer diameter of 0.5mm and thickness of 0.13mm is used in the experiments. In this experiment, we verify the effectiveness of the developed rotary laser dieless drawing apparatus.
Validation of Dynamic Hardening Models with Taylor Impact Tests at High Strain Rates
Authors: Piao Ming Jun , Park Chung Hee , Huh Hoon , Lee Ik Jin
Published: August 2014

This paper is concerned with the hardening behavior of 4340 steel at high strain rates from 104s-1to 106s-1. Tension tests were conducted using Instron 5583, HSMTM and SHPB testing machines at a wide range of strain rate from 10-3s-1to 103s-1. Three different impact velocities were performed for the Taylor impact tests to evaluate the reliability of Johnson–Cook model, modified Johnson–Cook model, modified Khan–Huang model, and Lim–Huh model at high strain rates for 4340 steel.
An Evaluation on Strain Dependency and Strain Rate Sensitivity of Martensitic Transformation Generated in TRIP Steel by Measurement of Magnetic Permeability
Authors: Moriyama Yutaro , Inoshita Daiki , Iwamoto Takeshi
Published: August 2014

If TRIP steel with excellent mechanical properties dominated by strain induced martensitic transformation (SIMT) can be applied to a shock absorber in automobiles, it becomes possible to reduce a weight of the automobiles by decreasing the thickness of their components. In order to improve its reliability by clarification of the mechanical properties, it is necessary to evaluate continuous evolution of martensite during deformation in TRIP steel. In the previous studies, volume resistivity and impedance have been measured during deformation. However, these studies have not been succeeded for the evaluation of martensite with higher precision. Here, because of focusing on a characteristic which martensite indicates ferromagnetism, the evolution of martensite is evaluated by measuring relative magnetic permeability in TRIP steel during deformation at various strain rate.
Roof Structure Design and Evaluation for Improvement of Roof Strength of Three-Wheel Vehicles
Authors: Yoo Je Sung , Kwon Jun Beom , Huh Hoon
Published: August 2014

This paper is concerned with auto-body frames and roof structures against rollover motion which could take place frequently with TWVs compared to FWVs because of the major difference of the loading between the two motions. Topology optimization is utilized for conceptual design and preliminary design of the roof structure for various loading conditions. The roof structure for TWV consists of existing part of FWV and a new part called Cross-bar reinforcement. Although a test method for regulation of roof strength is with static loading, simulations are carried out for both static and dynamic cases. In the dynamic loading case, rate-dependency of a material needs to be considered for accurate results of FE analysis.
Creep Behavior Study for Carbon Fiber Nano-Composites
Authors: Li Yi Luen , Chou Tsung Yu , Shen Ming Yuan , Chen Wei Jen , Chiang Chin Lung , Yip Ming Chuen
Published: August 2014

The surface modification of carbon nanotubes (CNTs) has been recently observed to influence the distribution of CNTs in epoxy resin and the mechanical properties and electrical conductivities of these CNTs. Accordingly, the treatment of CNTs to with organic acids to oxidize them generates functional groups on the surface of CNTs. This investigation studies the consequent enhancement of the mechanical properties and electrical conductivities of CNTs. The influence of adding various proportions of CNTs to the epoxy resin on the mechanical properties and electrical conductivities of the composites thus formed is investigated, and the strength of the material is tested at different temperatures.The test results also indicate that mechanical strength and electrical conductivity increase with the amount of CNTs added to the composites. Different coefficients of expansion of the matrix, fiber and CNTs, are such that overexpansion of the matrix at high temperature results in cracking in it.Moreover, the creep behaviors of carbon fiber (CF) /epoxy resin thermosetting composites and CNTs/CF/ epoxy resin composites were tested and analyzed at different stresses, orientations of fiber, temperatures and humidities. The creep exhibits only two stages-primary creep and steady-state creep. The effects of creep stress, creep time, and humidity on the creep of composites that contain various proportion of CNTs were investigated at various temperatures.Additionally, increasing the number of cycles in cyclic creep tests at room temperature resulted in a decrease in creep strain even at a high temperature of 55°C. Possible room temperature creep mechanisms have been proposed and discussed. With increasing number of creep tests, the creep strain decreased due to strain hardening which occurred during creep. Creep strain is believed to increase with applied stress, creep time, humidity, temperature and degree of the angle θ between the orientation of fiber and the direction of the applied stress.Finally, the test results of creep strain of CF/epoxy resin composites and CNTs/CF/epoxy resin composites tested under various conditions can be smoothly fitted by the fitting curves of Findley power law.
Computational Simulation of Micro- to Macroscopic Deformation Behavior of Cavitated Rubber Blended Amorphous Polymer Using Second-Order Homogenization Method
Authors: Uchida Makoto , Tada Naoya
Published: August 2014

To evaluate the effect of the size of the microstructure on the mechanical property of the cavitated rubber blended (voided) amorphous polymer, the FEM simulation based on the rate form second-order homogenization method, in which rates of the macroscopic strain and strain gradient are given to the microstructure, was performed. Computational simulations of micro-to macroscopic deformation behaviors of amorphous polymers including different sizes and volume fractions of the voids were performed. Non-affine molecular chain network theory was employed to represent the inelastic deformation behavior of the amorphous polymer matrix. With the increase in the volume fraction of the void, decrease and periodical fluctuation of stress and localized deformation in the macroscopic field were observed, and were more emphasized with the increase in the size of the void. These results were closely related to the non-uniform deformation and volume increase of the void in the microscopic field.
Synthesis and Properties of Cross-Linkable Waterborne Polyurethane/HMMM-CNT Nanocomposite
Authors: Rahman Mohammad Mizanur , Shaikh M. Nasiruzzaman
Published: August 2014

A series of cross-linked waterborne polyurethane/hexamethoxymethylmel-amine-carbon nanotube nanocomposites (WBPU/HMMM-CNT) were synthesized using carboxylic group functionalized CNT. The carboxylic groups on CNT were reacted with the methoxy groups of HMMM to get bonded HMMM-CNT. Unreacted methoxy group of HMMM-CNT was crosslinked with the carboxylic acid salt groups of WBPU and made crosslinked WBPU/HMMM-CNT nanocomposite. The mechanical properties (tensile strength and Young’s modulus) of conventional WBPU, crosslinked WBPU/HMMM, WBPU/CNT and WBPU/HMMM-CNT nanocomposites were compared under three conditions: untreated, wet and dried. It was observed that the mechanical properties of the crosslinked WBPU/HMMM-CNT nanocomposites were the least affected by water compared to conventional WBPU, crosslinked WBPU/HMMM, and WBPU/CNT nanocomposites. Differential scanning calorimetry (DSC) analysis also confirmed that the WBPU/HMMM-CNT nanocomposite can absorbed least water which can be easily removed by heating without destroying their crystalline structure. Crosslinked WBPU/HMMM-CNT nanocomposite recovered most of its mechanical properties of (with optimum HMMM-CNT content) after drying.
Computation of HAZ Hardness for Low Alloyed Welded Steels Using Five-Parameter Logistic Function
Authors: Bodea Marius , Mureşan Radu
Published: August 2014

The mechanical properties of the welded structures are directly related to the weldability of the steels, thus the estimation of the microstructural constituents in the weld and maximum hardness in the HAZ according to the welding process parameters represent a problem of great interest. The microstructural changes in the HAZ are estimated using a five-parameter logistic function (5PL), which is very accurate in the fitting highly asymmetric data. Also, the same 5PL function can be used in order to predict hardness and toughness in the HAZ based on the heat flow, cooling rates between 800-500 oC and chemical composition of the material. A discussion about the parameters of the 5PL function and fitting experimental data is presented and a studied case for welding S355J2 steel plates is also analyzed.
Preparation and Characterization of Amorphous Soft Magnetic FeSiB Powders and Spark Plasma Sintered Compacts
Authors: Neamţu Bogdan Viorel , Marinca Traian Florin , Chicinaş Ionel , Popa Florin , Isnard Olivier
Published: August 2014

Wet mechanical alloying (MA) were used to prepare amorphous soft magnetic Fe75Si20B5 (at.%) powders starting from elemental powders of Fe, Si and B. The structural, morphological and magnetic properties of the powders were investigated. It was found that wet MA leads to the amorphisation of the alloy after 40 hours of wet milling using benzene (C6H6) as process control agent (PCA). The influence of the wet MA process on the saturation magnetization of the powders was investigated. Amorphous powder of Fe75Si20B5 (at.%) obtained by wet MA route was used to prepare compacts by spark plasma sintering (SPS). The chosen sintering temperature was 800, 850 and 900 oC. Toroidal samples of Fe75Si20B5 (at.%) were investigated in DC and AC magnetization regime and their magnetic properties were correlated with sintering parameters, compacts density and phases evolution during sintering.
Research about Relation between the Microstructures and Mechanical Properties of Metal Coating Layers
Authors: Olàh Arthur , Tierean Mircea Horia
Published: August 2014

The paper presents the research about the correlation between the microstructures and mechanical properties of metal coating layers after laser heat treatment. The research was made with eight types of electrodes for welding coating. Laser heat treatment was applied after coating. Evaluation of results was made by observing the microstructures with metallographic microscopy, SEM/EDX and the mechanical properties were obtained by microhardness and wear resistance. The goal of this research is to study the influence of the laser heat treatment on wearing resistance of metal coating layers. Results reveal the influence of microstructures and chemical composition of used electrodes on microhardness and wear resistance of metal coating layers.
Research on Microstructure and Properties of the Active Surface of Bimetallic Tools for Plastic Deformation at Hot or Cold
Authors: Luca Mihai Alexandru , Machedon Pisu Teodor
Published: August 2014

Tools for plastic deformation at hot or cold are made of medium or high alloyed special steels, which are relatively expensive. To reduce the material costs of these tools, it is possible to manufacture them of low alloyed steels. In this case it was used steel 42CrMo4 (1.7225). The active surface of these tools is carried out by charging a welding wear resistant material. Within the framework of research it was used the VTCr25W4TiLa filler material, made in the form of tubular rod designed for WIG process deposits or oxyacetylene flame of wear-resistant layers. Anti-wear layers made austenitic structure, in which fine carbides of Cr, W and Ti are embedded. These layers are characterized by high abrasion resistance , combined with corrosion resistance and thermomechanical fatigue. Depending on the heat treatment applied can be obtained usable tools for plastic deformation at hot or cold.
Welding of AA2124/SiC/25p-T4 by FSW at High Welding Speed and Monitoring the Process by Real-Time Control of Infrared Termography and Energy Consumption
Authors: Pop-Calimanu Marius , Cojocaru Radu , Ciucă Cristian , Fleșer Traian , Ciorpac Petronela Lucia
Published: August 2014

The objective of this study is to present the feasibility of welding of AA2124/SiC/25p-T4 metal matrix composite at high welding speed by friction stir welding. We carried out the analysis of the microstructure, microhardness, and tensile test of welded sample from different areas, to evaluate the performance of the weld. The phase structure of AA2124/SiC/25p-T4 metal matrix composite was determined by X-ray diffraction (XRD). The temperature monitoring and measurements in the welding zone, in different areas was made, using infrared thermography to demonstrate that the FSW welds of AA2124/SiC/25p-T4 is below the melting temperature of the base material and to see the temperature distribution during the process. In addition, the monitoring and the control of energy consumption was achieved.
Edge Fillet Laser Welding of AISI 304 Stainless Steel
Authors: Stanciu Elena Manuela , Pascu Alexandru , Roată Ionut Claudiu
Published: August 2014

This investigation concerns the influence of key parameters of laser welding on the geometry and microstructural properties of the weld bead. The study is intended to restrain the interval field of the welding parameters and to investigate the welded joints achieved through this technique.
A 3,3 kW Nd:YAG laser together with a Rofin welding head and an ABB 6-axes robot were used for this investigation. The tests highlight the major influence of the laser spot diameter on the geometry of weld bead. The experiments were made on various samples of AISI 304 thin sheets. In depth characterization of the weld area was conducted by means of optic and electronic microscopy and EDS analyses.
Influence of the Electric Field Voltage on the Microhardness of the Layers Coated by Thermal Spraying
Authors: Roată Ionut Claudiu , Pascu Alexandru , Stanciu Elena Manuela
Published: August 2014

This study focuses on the analysis of the electric field voltage influence on the microhardness of the layers coated by thermal spraying. Based on the fact that the loads that are oppositely signed are attracted, an electric device of electric field generating in alternating current is developed, the electric field being generated between the metalizing gun and the work piece. Any metallic body that crosses the electric field is loaded with electric loads, which are yielded by an electric discharge when meeting the oppositely signed load. Thus, the physical and chemical properties of the layers coated by thermal spraying are improved by enhancing the powders displacement speed and by the appearance of micro weldings at the impact between the powder and the metalizing piece. After the samples analysis, an improvement of the diffusion zone is noticed and also an increasing of the microhardness for the samples at which the following voltages are used U = 30; 50; 70 [. In order to achieve the experimental samples, the CastoDyn DS8000 thermal spraying unit, the standard metallization module SSM 10 and the nickel based powder ProXon 21021 were used.
Influence of Cooling Rate on the Structural Characteristics of Ca and Rare Earth Inoculated, Low-S Grey Cast Iron
Authors: Harcea Lavinia Marilena , Riposan Iulian
Published: August 2014

The structural characteristics of low S (0.025%), low Al (<0.003%) and 4.0% carbon equivalent (CE) electric melted grey irons were studied at different solidification rates, for Ca and Ca,RE [Mischmeta as the inoculating elements. Despite a relatively high CE, this base iron is sensitive to undercooling during solidification. A conventional Ca-FeSi inoculant is not recommended for these critical conditions, especially to avoid undercooled graphite morphologies. It is only adequate to control free carbides, for castings with more than 15mm section. Rare earth (RE) bearing CaFeSi alloy appears to be a more effective solution, at least for castings with more than 5mm section to control carbides, even the end effect, and promote a homogeneous structure. Undercooled graphite presence was limited and avoided in more than 10mm section. Thin wall castings, less than 5mm section, requiring stronger control for carbides and undercooled graphite formation, should not be produced from this type of base iron, unless more efficient inoculation can be accomplished.
Analysis of Hazards Identified within the Premises of the Electric Steelworks, to Carry out the Risk Assessment
Authors: Haranguş Victoria , Vasilescu Gabriel , Todoruţ Adela , Hepuţ Teodor
Published: August 2014

In steelmaking and casting, there are used, stored and handled chemicals which are risk factors either in the normal operation of the technical plants, or in predictable and unpredictable failure conditions. In the steelmaking and casting plants, the substances and liquids considered risk factors are: methane, oxygen, liquid steel and water used for the cooling system. This paper deals with the risk assessment within the premises of electric steelworks, in predictable failure situations, based on the sheets of assessment and reduction of the risk associated with explosive atmospheres of methane and oxygen, in the presence of high temperatures existing at the electric steelworks.
Phlebotomy and quality in the African laboratory
Authors: Mbah Henry A.
Published: August 2014

Phlebotomy, the act of drawing blood through venepuncture, is one of the most common medical procedures in healthcare, as well as being a basis for diagnosis and treatment. A review of the available research has highlighted the dearth of information on the phlebotomy practice in Africa. Several studies elsewhere have shown that the pre-analytical phase (patient preparation, specimen collection and identification, transportation, preparation for analysis and storage) is the most error-prone process in laboratory medicine. The validity of any laboratory test result hinges on specimen quality; thus, as the push for laboratory quality improvement in Africa gathers momentum, the practice of phlebotomy should be subjected to critical appraisal. This article offers several suggestions for the improvement of phlebotomy in Africa.
Neurosurgery and pregnancy
Authors: Subramanian Rajkumar , Sardar Arijit , Mohanaselvi S. , Khanna Puneet , Baidya Dalim
Published: August 2014

Pregnant patients rarely present with neurosurgical emergencies, but can cause significant morbidity and mortality to the mother and the foetus. Physiological changes of pregnancy in relevance to neurosurgery, effects of anaesthetic agents on the foetus, common neurosurgical emergencies, and anaesthetic implications both from obstetric and neurosurgical point of view are discussed in this review.
Comparison of bupivacaine and bupivacaine plus magnesium sulphate infiltration for postoperative analgesia in patients undergoing lumbar laminectomy: A prospective randomised double-blinded controlled study
Authors: Donadi Praveen , Moningi Srilata , Gopinath Ramachandran
Published: August 2014

Background: Laminectomy is associated with considerable postoperative pain. Providing analgesia locally in the area of surgical trauma, with minimal systemic side effects, is an attractive option and has become an integral part of multimodal analgesia. The objective of this study was to assess and compare the effectiveness and safety of local infiltration of bupivacaine and bupivacaine plus magnesium sulphate for postoperative analgesia in patients undergoing lumbar laminectomy. Materials and Methods: Sixty adult patients of the American Society of Anaesthesiologists (ASA) class 1 and 2 were randomly allocated into two groups, comprising 30 patients in each group. After the completion of lumbar laminectomy, the study drug was locally infiltrated into the paravertebral muscles on either side. Group bupivacaine with magnesium (BM) was given 20 ml of 0.25% bupivacaine with 500 mg of magnesium sulphate (constituted with normal saline); and Group bupivacaine (B) was given 20 ml of 0.25% bupivacaine constituted with normal saline. Postoperative visual analogue scale (VAS) pain scores at 1, 2, 4, 6, 8, 12 and 24 hours; rescue analgesia, the time to first analgesic consumption, degree of overall patient satisfaction and side effects were recorded. Comparison of continuous data between groups was done using independent T-test. Comparison of nominal data was done using Chi-square analysis and ordinal data using Mann-Whitney test. A P value less than 0.05 was considered significant. Results: Time to first analgesic consumption was significantly longer in BM group (7.78 ± 1.350 hours) compared to B group (4.62 ± 0.997 hours) (P < 0.0001). The consumption of Tramadol was significantly higher in B group (202.5 ± 76.9 mg) compared to BM (117.5 ± 63.4 mg) (P < 0.0001). The degree of overall satisfaction with postoperative pain management on a 4-point satisfaction scale was better in BM group (2.77 ± 0.626) compared to B group (2.0 ± 0.587) (P < 0.001). Conclusion: Wound infiltration with bupivacaine and magnesium sulphate provided better pain control and analgesic effect was more significant, providing effective and safe postoperative analgesia in patients undergoing laminectomy surgeries.
Periodic Solutions of Almost Linear Volterra Integro-dynamic Equations on Periodic Time Scales
Authors: Raffoul Youssef N.
Published: August 2014

Using Krasnoselskii’s fixed point theorem, we deduce the existence of periodic solutions of nonlinear system of integro-dynamic equations on periodic time scales. These equations are studied under a set of assumptions on the functions involved in the equations. The equations will be called almost linear when these assumptions hold. The results of this paper are new for the continuous and discrete time scales.
Transport of aerosol to the Arctic: analysis of CALIOP and French aircraft data during the spring 2008 POLARCAT campaign
Authors: Ancellet G. , Pelon J. , Blanchard Y. , Quennehen B. , Bazureau A. , Law K. S. , Schwarzenboeck A.
Published: August 2014

Abstract. Lidar and in situ observations performed during the Polar Study using Aircraft, Remote Sensing, Surface Measurements and Models, Climate, Chemistry, Aerosols and Transport (POLARCAT) campaign are reported here in terms of statistics to characterize aerosol properties over northern Europe using daily airborne measurements conducted between Svalbard and Scandinavia from 30 March to 11 April 2008. It is shown that during this period a rather large number of aerosol layers was observed in the troposphere, with a backscatter ratio at 532 nm of 1.2 (1.5 below 2 km, 1.2 between 5 and 7 km and a minimum in between). Their sources were identified using multispectral backscatter and depolarization airborne lidar measurements after careful calibration analysis. Transport analysis and comparisons between in situ and airborne lidar observations are also provided to assess the quality of this identification. Comparison with level 1 backscatter observations of the spaceborne Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP) were carried out to adjust CALIOP multispectral observations to airborne observations on a statistical basis. Recalibration for CALIOP daytime 1064 nm signals leads to a decrease of their values by about 30%, possibly related to the use of the version 3.0 calibration procedure. No recalibration is made at 532 nm even though 532 nm scattering ratios appear to be biased low (−8%) because there are also significant differences in air mass sampling between airborne and CALIOP observations. Recalibration of the 1064 nm signal or correction of −5% negative bias in the 532 nm signal both could improve the CALIOP aerosol colour ratio expected for this campaign. The first hypothesis was retained in this work. Regional analyses in the European Arctic performed as a test emphasize the potential of the CALIOP spaceborne lidar for further monitoring in-depth properties of the aerosol layers over Arctic using infrared and depolarization observations. The CALIOP April 2008 global distribution of the aerosol backscatter reveal two regions with large backscatter below 2 km: the northern Atlantic between Greenland and Norway, and northern Siberia. The aerosol colour ratio increases between the source regions and the observations at latitudes above 70° N are consistent with a growth of the aerosol size once transported to the Arctic. The distribution of the aerosol optical properties in the mid-troposphere supports the known main transport pathways between the mid-latitudes and the Arctic.
Development of a cavity-enhanced aerosol albedometer
Authors: Zhao W. , Xu X. , Dong M. , Chen W. , Gu X. , Hu C. , Huang Y. , Gao X. , Huang W. , Zhang W.
Published: August 2014

Abstract. We report on the development of a cavity-enhanced aerosol single-scattering albedometer based on incoherent broadband cavity-enhanced absorption spectroscopy (IBBCEAS) combined with an integrating sphere (IS) for simultaneous in situ measurements of aerosol scattering and extinction coefficients in an exact same sample volume. The cavity-enhanced albedometer employed a blue light-emitting-diode (LED)-based IBBCEAS approach for the measurement of wavelength-resolved aerosol optical extinction over the spectral range of 445–480 nm and an integrating sphere nephelometer coupled to the IBBCEAS setup for the measurement of aerosol scattering. The scattering signal was measured with a single-channel photomultiplier tube (PMT), providing an averaged value over a narrow bandwidth (full-width at half-maximum, FWHM, ~ 9 nm) in the spectral region of 465–474 nm. A scattering coefficient at a wavelength of 470 nm was deduced as an averaged scattering value over the spectral region of 465–474 nm and used for data analysis and instrumental performance comparison. Performance evaluation of the albedometer was carried out using laboratory-generated particles and ambient aerosol. The scattering and extinction measurements of monodisperse polystyrene latex (PSL) spheres generated in the laboratory proved excellent correlation between two channels of the albedometer. The retrieved refractive index (RI) of the PSL particles from the measured scattering and extinction efficiencies agreed well with the values reported in previously published papers. Aerosol light scattering and extinction coefficients, single-scattering albedo (SSA) and NO2 concentrations in an ambient sample were directly and simultaneously measured using the albedometer developed. The instrument developed was validated via an intercomparison of the measured aerosol scattering coefficients and NO2 trace gas concentrations to a TSI 3563 integrating nephelometer and a chemiluminescence detector, respectively.
Topside signature of medium-scale traveling ionospheric disturbances
Authors: Miller E. S. , Kil H. , Makela J. J. , Heelis R. A. , Talaat E. R. , Gross A.
Published: August 2014

Abstract. Plasma blobs, localized plasma density enhancements that occur singularly or in periodic groups, have been observed by in situ sensors in the lower- and middle-latitude nighttime ionosphere. Traditionally, creation of blobs has been thought to be connected to equatorial plasma bubbles, which are localized plasma depletions. Here, we report the association of blobs with medium-scale traveling ionospheric disturbances (MSTIDs). On 17 January 2010, an all-sky imager on the Caribbean island of Bonaire (geographic: 12.190° N, 68.244° W; geomagnetic 22.46° N, 7.099° E) observed a nighttime electrified MSTID propagating to the southwest. At the time of the MSTID's transit, the Coupled Ion-Neutral Dynamics Investigation instrument onboard the Communication/Navigation Outage Forecasting System satellite detected a group of blobs along the same geomagnetic flux tubes. The electron density variations measured at the satellite altitude, indicating the blobs, are anticorrelated with the intensity variations of the 630.0 nm dissociative recombination emission measured on the same magnetic field lines. This relationship is explained by a modulation of the O+ profile altitude due to electric fields generated within the MSTID. This idea is supported by in situ measurements of the vertical ion velocity. We argue that common climatology between blobs and MSTIDs reported in the literature, as well as this coincident observation, suggest that blobs may be the in situ signature of MSTIDs in the topside ionosphere.
Onafhankelijkheid vs. Accountability: de casus van de nieuwe EU financiële toezichthouders
Authors: Scholten M.
Published: August 2014

Samenvatting

Dit artikel analyseert de onafhankelijkheid en accountability van de nieuwe EU financiële agentschappen (EBA, EIOPA en ESMA). Het behandelt eerst de de jure institutionele, persoonlijke en financiële elementen van de onafhankelijkheids- en accountability arrangementen van de nieuwe agentschappen en laat zien dat zowel hun onafhankelijkheid als accountability versterkt is in vergelijking met die van hun voorgangers, de zogenoemde Lamfalussy-comités. Verder wordt een aantal punten met betrekking tot de de facto onafhankelijkheid en accountability van EU-agentschappen besproken. Het artikel sluit af met een aantal lessen die uit de EU-ervaring getrokken kunnen worden. Het biedt daarmee nuttige inzichten aan nationale wetgevers die zich met het ‘onafhankelijkheid vs. accountability’-dilemma geconfronteerd zien.
The master cell cycle regulator APC-Cdc20 regulates ciliary length and disassembly of the primary cilium
Authors: Wang Weiping , Wu Tao , Kirschner Marc W
Published: August 2014

The primary cilium has an important role in signaling; defects in structure are associated with a variety of human diseases. Much of the most basic biology of this organelle is poorly understood, even basic mechanisms, such as control of growth and resorption. We show that the activity of the anaphase-promoting complex (APC), an E3 that regulates the onset of anaphase, destabilizes axonemal microtubules in the primary cilium. Furthermore, the metaphase APC co-activator, Cdc20, is specifically recruited to the basal body of primary cilia. Inhibition of APC-Cdc20 activity increases the ciliary length, while overexpression of Cdc20 suppresses cilium formation. APC-Cdc20 activity is required for the timely resorption of the cilium after serum stimulation. In addition, APC regulates the stability of axonemal microtubules through targeting Nek1, the ciliary kinase, for proteolysis. These data demonstrate a novel function of APC beyond cell cycle control and implicate critical role of ubiquitin-mediated proteolysis in ciliary disassembly.
History Repeats—The Election Battle for Medicaid in 2024
Authors: Amba Vineeth , Cooper Morgan S. L. , Sommers Benjamin D.
Published: August 2024

This Viewpoint explores partisan attitudes toward Medicaid in the 2024 US election and the implications for access to care and health equity if a Republican proposal that includes work requirements and block grants moves forward.
Accuracy of ICD-10 Diagnostic Codes for Identifying Housing Instability
Authors: O’Brien Matthew J. , Owen Andrew , Langshur Sharon , Doblin Bruce , Hinami Keiki , Trick William , Liss David T.
Published: August 2024

This cohort study assesses the performance of International Statistical Classification of Diseases and Related Health Problems, Tenth Revision (ICD-10) Z59 codes for identifying housing instability during health care encounters.
Early Childhood Screen Use Contexts and Cognitive and Psychosocial Outcomes
Authors: Mallawaarachchi Sumudu , Burley Jade , Mavilidi Myrto , Howard Steven J. , Straker Leon , Kervin Lisa , Staton Sally , Hayes Nicole , Machell Amanda , Torjinski Marina , Brady Brodie , Thomas George , Horwood Sharon , White Sonia L. J. , Zabatiero Juliana , Rivera Clara , Cliff Dylan
Published: August 2024

Importance

The multifaceted nature of screen use has been largely overlooked in favor of a simplistic unidimensional measure of overall screen time when evaluating the benefits and risks of screen use to early childhood development.

Objective

To conduct a systematic review and meta-analysis to examine associations of screen use contexts in early childhood with cognitive and psychosocial outcomes.

Data Sources

PsycINFO, Embase, MEDLINE Ovid, ProQuest, CINAHL, Web of Science, and Scopus were searched from inception to December 31, 2023.

Study Selection

A total of 7441 studies were initially identified. Studies were included if they examined associations between a contextual factor of screen use among children aged 0 to 5.99 years and cognitive or psychosocial development. Observational, experimental, and randomized clinical trial study designs were included.

Data Extraction and Synthesis

All studies were independently screened in duplicate following PRISMA guidelines. Effect sizes of associations (r) from observational studies were pooled using random-effects 3-level meta-analyses. The remaining study designs were narratively synthesized.

Main Outcomes and Measures

Screen use contexts included content (child directed and age inappropriate), type (program viewing and game or app use), co-use (or solo use), background television, caregiver screen use during child routines, and purpose. Outcomes were cognitive (executive functioning, language, and academic skills) or psychosocial (internalizing and externalizing behavior problems and socioemotional competence).

Results

Overall, 100 studies (176 742 participants) were included, and of these, 64 observational studies (pooled sample sizes ranging from 711 to 69 232) were included in meta-analyses. Program viewing (n = 14; k = 48; r, −0.16; 95% CI, −0.24 to −0.08) and background television (n = 8; k = 18; r, −0.10; 95% CI, −0.18 to −0.02) were negatively associated with cognitive outcomes, while program viewing (n = 6; k = 31; r, −0.04; 95% CI, −0.07 to −0.01), age-inappropriate content (n = 9; k = 36; r, −0.11; 95% CI, −0.17 to −0.04), and caregiver screen use during routines (n = 6; k = 14; r, −0.11; 95% CI, −0.20 to −0.03) were negatively associated with psychosocial outcomes. Co-use was positively associated with cognitive outcomes (n = 8; k = 28; r, 0.14; 95% CI, 0.03 to 0.25).

Conclusions and Relevance

Findings show small to moderate effect sizes that highlight the need to consider screen use contexts when making recommendations for families, clinicians, and educators beyond screen time limits; including encouraging intentional and productive screen use, age-appropriate content, and co-use with caregivers.
Effect of Shared Decision‐Making on Trust in Physicians in the Management of Systemic Lupus Erythematosus: The Trust Measurement for Physicians and Patients With Systemic Lupus Erythematosus Prospective Cohort Study
Authors: Yoshimi Ryusuke , Yajima Nobuyuki , Hidekawa Chiharu , Sakurai Natsuki , Oguro Nao , Shidahara Kenta , Hayashi Keigo , Ichikawa Takanori , Kishida Dai , Miyawaki Yoshia , Sada Ken‐ei , Shimojima Yasuhiro , Ishikawa Yuichi , Yoshioka Yuji , Kunishita Yosuke , Kishimoto Daiga , Takase‐Minegishi Kaoru , Kirino Yohei , Ohno Shigeru , Kurita Noriaki , Nakajima Hideaki
Published: August 2024

Objective

Few studies have explored whether the involvement of patients in shared decision‐making (SDM) is beneficial to the management of systemic lupus erythematosus (SLE). Therefore, this study investigated the relationship between patient participation in SDM and their trust in physicians using data from the Trust Measurement in Physicians and Patients With SLE (TRUMP2‐SLE) study.

Methods

Data regarding the nine‐item Japanese version of the Shared Decision‐Making Questionnaire (SDM‐Q‐9) scores, Trust in Physician Scale (TIPS) scores, and Abbreviated Wake Forest Physician Trust Scale (A‐WFPTS) scores for interpersonal trust in a physician and trust in the medical profession were collected from patients with SLE who visited the outpatient clinics of five facilities in Japan through a self‐administered questionnaire. The relationships among these scores were analyzed by general linear models with cluster‐robust variance.

Results

This study included 433 patients with SLE. The median baseline TIPS and A‐WFPTS (attending physician version) scores were 82 (73–93) and 80 (70–95), respectively. A higher baseline SDM‐Q‐9 score was correlated with an increase in the TIPS score at one year (coefficient per 10‐point [pt] increase, 0.94 pts, 95% confidence interval [CI] 0.16–1.72). A higher baseline SDM‐Q‐9 score was correlated with a higher A‐WFPTS score for interpersonal trust (coefficient per 10‐pt increase, 2.20 pts, 95% CI 1.44–2.96). The baseline SDM‐Q‐9 score was also correlated with an increase in the general physician version of the A‐WFPTS score at one year (coefficient per 10‐pt increase, 1.29 pts, 95% CI 0.41–2.18).

Conclusion

Engagement of patients with SLE in SDM elevates their trust in the attending physicians and health care providers, potentially enhancing doctor–patient relationships and overall health care trust.
Conversion of Aluminum to Hydrogen: A Metallurgical Point of View
Authors: Eskin Dmitry G.
Published: August 2024

Transition to the Net‐Zero economy requires new sources of energy. Hydrogen is one of the promising candidates to replace carbohydrates. Emission‐free technologies for hydrogen production are pivotal for this transition. However, the existing technologies to produce hydrogen are either polluting or energy‐intensive. In recent years, a reaction of aluminum with water generating hydrogen has attracted a lot of attention. Most of the research is done with solid aluminum and analyzed mostly from the chemical and energy points of view. In this overview paper, rarely mentioned metallurgical aspects of this reaction are considered, as well as potential integration of the related technology into a green aluminum production cycle. The advantages of using liquid aluminum as well as related safety aspects are highlighted.
Transparent Perovskite Wafers via Nanocrystals Ordered Coalescence Toward Sensitive and Stable X‐Ray Detection and Imaging
Authors: Tan Wenyan , Xiao Yingrui , Zhou Chao , Jin Xi , Zhu Siyuan , Han Mingyue , Tang Zhaoheng , Zhang Yu , Su Zhenhuang , Chen Tongsheng , Chen Qi , Liang Qijie , Chen Weiqiang , Jiang Yan
Published: August 2024

Metal halide perovskite wafers have shown significant potential in large‐area X‐ray detection and imaging. However, a distinct difference in optical transparency between state‐of‐the‐art perovskite wafers and single crystals indicates the inferior crystal quality of perovskite wafers, which limits the performance and stability of wafer‐based X‐ray detectors. Here, nano‐sized MAPbBr3 powders are utilized to fabricate dense perovskite wafers by low‐temperature hot‐pressing with high transparency above 60% within the 552–800 nm wavelength range. Adjacent nanocrystals assemble following the ordered coalescence mechanism, resulting in the exclusion of nanoscopic pores and crystallographic reorientation. The transparent MAPbBr3 wafer‐based detectors achieve an impressively high X‐ray sensitivity of 1.14 × 105 µC Gyair−1 cm−2 and a low detection limit of 149 nGyair s−1, which is superior to opaque MAPbBr3 wafer detectors (5.64 × 104 µC Gyair−1 cm−2 and 316.7 nGyair s−1) and comparable to MAPbBr3 single‐crystal detectors. Moreover, the detectors demonstrate high uniformity and outstanding stability under continuous X‐ray irradiation of a total dose of up to 5.9 Gyair, equaling to 29 500 times posteroanterior chest examinations. The high sensitivity and low detection limit of the detectors lead to clear X‐ray imaging performance.
Insulating Polymer Mediated Stability and Photovoltaic Performance of Organic Solar Cells: Influence of Molecular Weight
Authors: Xia Weiyi , Zhou Bojun , Wang Liang , Guo Chuanhang , Zhou Jinpeng , Cheng Jingchao , Sun Wei , Chen Chen , Gan Zirui , Li Wei , Liu Dan , Wang Tao
Published: August 2024

Insulating polymers are promising components for constructing high performance organic solar cells (OSCs) due to their advantages including low cost, excellent mechanical properties, and feasibility in morphology modulation. However, few studies have been conducted on the effect of molecular weight of insulating polymers on the performance of the corresponding OSCs. In this work, polymethyl methacrylate (PMMA) with different molecular weight (named as PMMAL and PMMAH) are incorporated into a range of polymer:nonfullerene photovoltaic systems. It is found that although both PMMAL and PMMAH can suppress the energetic disorder and the nonradiative energy loss, and lead to enhanced open‐circuit voltage in their corresponding OSCs, distinct mechanical property, operational stability as well as photovoltaic performance are observed. PMMAL can modulate the molecular packing of the host components more effectively due to its superior chain segment mobility during the film‐forming process, which can drive the host components to form more ordered molecular packing and therefore superior photovoltaic performance. On the other hand, due to the better miscibility of PMMAH with the host system, especially the C5‐16 acceptor, PMMAH can be well dispersed in the host and form a stable framework that provides superior mechanical properties and operational stability.
A Self‐Assembled Hybrid Electrode with Efficient Tandem Electrochemistry for Dissolution‐Shielding, Ultrafast‐Charging, and Record‐Lifespan Zinc‐Ion Batteries
Authors: Yang Ming , Chen Minfeng , Lai Mengnan , Chen Hongli , Wang Yanyi , Zhu Jianhui , Ma Dingtao , Sun Lingna , Mi Hongwei , He Chuanxin , Chen Jizhang , Zhang Peixin
Published: August 2024

The design of electrode compatible with wide‐temperature, fast‐charging, and long‐lifespan aqueous zinc‐ion batteries is a great challenge that urgently needs addressing. However, the mismatch between runaway host dissolution and high interfacial hydrophilicity within electrode is a contradictory problem that restricts their electrochemical performance. In this report, take the typical vanadium diselendie (VSe2) host for example, by employing the natural polymer bacterial cellulose (BC) as the multifunctional mediator, a design paradigm of self‐assembly hybrid electrode with efficient tandem electrochemistry is presented. Theoretical and experimental research confirmed that such BC‐mediated hybrid structure exhibits multiple functions to well balance the cathode dissolution and storage kinetics. Impressively, such an electrode displayed an excellent rate capability (1–50 A g−1), and an unexpected record‐lifespan of 45 000 cycles. Beyond that, it also shows a good temperature‐tolerance ability, remaining the high specific capacities of 120 and 288 mAh g−1 (at 10 A g−1) after 3000 cycles at −25 and 50 °C, respectively. Note that such approach is also applicable to the high‐voltage platform MnO2 and I2 hosts, demonstrating its potential for universality. This discovery can provide a new design principle of robust electrode for advanced aqueous zinc‐ion batteries.