bluuebunny/crossref_metadata_2025 huggingface dataset:
Experimental Study on High Temperature Pyrolysis Characteristics of Biomass Tar in Biomass Gasification-reburning Technology
Authors: He Peng , Zhang Qian , Zhang Bing , Liu Jinhua , Gong Guohong , Li Dong
Published: January 2020

In order to solve the problem of high-tar content of gasification products in biomass gasification-reburning technology, this thesis proposes an experimental scheme for high temperature thermal cracking of biomass tar, using representative rice hull tar as a sample, and self-designed pyrolysis experiment. On the stage, the reaction temperature of the gasification chamber was measured by a high-temperature thermocouple. At the same time, the biomass tar cracking rate was measured at different temperatures with the thermobalance by appropriately changing pyrolysis temperature, and the Agilent HP5973 GC/MS was employed to analyze the components of pyrolysis products of biomass tar under different temperature conditions. The experimental results show that the total thermal cracking rate of tar increased with the increasing of experimental temperature. In the temperature range of 550°C∼655°C, the increasing rate of thermal cracking becomed slower; when it reached between 655°C and 790°C, the thermal-cracking rate showed a significant growth trend; while entering 790°C∼853°C, the growth rate slowed down. The experimental and analytical results reveal the basic laws of high-temperature pyrolysis of biomass tar, and provide a certain technical basis for the industrial production of low-tar and high-quality biomass gas.
Effects of Friction Speed on Microstructures and Mechanical Properties of Friction Welded Super304H Welding Joints
Authors: Yang Xu , Lu Yuan , Li Debiao , Bi Cheng , Zhang Jianlong , Sun Fuyang , Cao Bo
Published: January 2020

The Super304H austenitic steel were welding though friction welding technique. The Super304H joints showed excellent microstructure and mechanical properties. The effects for friction speed on the microstructure and mechanical properties of Super304H welding joints was investigated. With an increase in the friction speed, the grains didn’t grow up and second-phase particles precipitates increased in welding joints. The tensile fracture location was in the Super304H heat affected zone. When the friction speed was increased, the tensile strength increased and impact toughness was decreased.
Numerical investigations of the flow distributions with a transient three-dimensional multi-component ejector model
Authors: Liu Zhanrui , Jiao Kui , Yang Zirong , Du Qing
Published: January 2020

Ejector is a promising hydrogen recirculation for proton exchange membrane fuel cell (PEMFC) systems since it does not require parasitic power consumption. However, the complicated transport mechanisms inside the ejector remain unclear. In this study, the heat and mass transport processes are investigated by a transient three-dimensional multi-component model. The distribution of velocity, temperature, and pressure are presented. To avoid water vapor condensation, the maximum primary flow pressure should be limited to prevent the formation of a low temperature region at the nozzle throat. Compared with the converging-diverging nozzle, the convergent nozzle is recommended since it increases the condensation of water vapor. To predict the lowest temperature, the relationship between the relative pressure and the temperature is further obtained by curve fitting methods.
Efficiency Calculation and Economic Analysis of Straight Fins with Various Shapes Based on Steady-state Heat Conduction
Authors: Chen Jiying , Jiang Shenghao , Hu Jiayi , Ji Jiaxin
Published: January 2020

Fins are an important means of heat transfer enhancement, which can increase the heat transfer area, reduce the heat resistance of convection heat transfer and enhance the heat transfer capacity of equipment. The analytical solutions of rectangular fins, trapezoidal fins and triangular fins in one dimension are given by using the direct solution method. Then the heat conduction of fins is discretized by the finite volume method (FVM). By solving the discrete linear equations, the numerical solutions of temperature distribution on the surface of fins with constant property and variable property are obtained. Based on the law of temperature distribution, the relationship between the length, the height and the width of fins and fin efficiency is explored, and its economic efficiency is discussed. The results show that the temperature gradient of rectangular fins is the smallest, and that of triangular fins is the most significant. For various shapes of fins, the most effective way to increase heat dissipation is to increase the width of the fin, and for the fin whose machining length is 1 unit, the efficiency of the first 20%∼30% part of the maximum length changes significantly, which can be used as the focus of cost optimization.
Slagging resistance mechanism of precursor ceramic coating for solid fuel-fired boilers
Authors: Wang Guangxin , Zhang Bing , Wang Jinqing , Chi Zuohe , Zhang Guangxue , li Jin , Wang Jie , Qian Peihao , Yang Songjie
Published: January 2020

Slag formation on the heating surface in solid fuel-fired boilers is a common problem. In this paper, with polysilazane used as the precursor, three different ceramic coatings were prepared by adding hexagonal boron nitride (h-BN), ZrO2, and Al2O3 inert fillers. The coatings were applied to a TP347 substrate by the Czochralski method. The spreading and solidification experiments of the molten ash were performed and matched with numerical simulation. The results show that compared with the steel sheet, the molten ash has a large contact angle on the coating, a small spreading coefficient and the same spreading time, indicating that the coating has the slagging resistance property. The coating with the addition of h-BN has better slagging resistance properties than the other two coatings. The numerical simulation results are consistent with the experimental results.
Fracture Analysis on Turbine Intermediate Regulating Valve of an Electric Generator Unit
Authors: Wang Tianpeng , Sui Yuqiu , Wang Yunan , Li Hongqiang , Sun Mingcheng , Dai Li , Wu Nan
Published: January 2020

A turbine intermediate regulating valve fractured in a power plant, and the reasons for the fracture were analysed by using macro morphology observation, mechanical properties test, chemical composition analysis and microstructure observation, such as scanning electron microscopy (SEM) analysis or metallographic analysis. The results indicated that the chemical composition and strength properties were in accordance with the standard requirements, but the elongation after fracture and the impact toughness value were all lower than the required values. Precipitation of σ phase further weakened the matrix and reduced the strength of the structure. Fretting friction and collision appeared between the valve stem and the anti-rotating pin, and additional stress was generated by the reduction of radial clearance between the pin and valve. Then cracks and brittle expansion occurred in the stress concentration areas close to the anti-rotating pin holes and finally fractured.
Application of BP neural network based on genetic algorithm optimization in thermal conductivity of nanofluids
Authors: Wang Jiang , Zhai Yuling
Published: January 2020

In this paper, a hybrid model (BP-GA) including a back propagation network and a genetic algorithm is used to estimate the thermal conductivity of the nanofluids. The genetic algorithm is used to optimize the initial weight and threshold of BP neural network, so that the optimized BP neural network can better predict the function output. In this study, CuO-ZnO hybrid nanofluids with the mass fraction of 0%, 1%, 2%, and 3% were studied at temperatures of 25, 30, 35, 40, 45, 50, 55, and 60 °C, respectively. The thermal conductivity of the hybrid nanofluids base liquid is 20:80, 40:60, 50:50, 60:40, 80:20, and the mass ratio of CuO-ZnO is 50:50. The mass fraction of CuO-ZnO, the temperature and the mixing ratio of different base liquids were used as input parameters, and the thermal conductivity was the output parameter, forming a 3-input ANN neural network. The predicted thermal conductivity results of BP neural network and genetic algorithm optimized BP neural network (GA-BP) were compared with experimental data. The results illustrate that the BP neural network optimized by genetic algorithm exerts a positive influence on the accuracy and stability of the predicted output.
Thermal stress analysis of printed circuit heat exchanger based on thermal-structural coupling method
Authors: Wu Jun , Yao Shuo , Zhao Zhenxing , Xiao Qi , Ke Zhiwu , Lin Yuansheng
Published: January 2020

The supercritical carbon dioxide (S-CO2) Brayton cycle has the advantages of high efficiency, compactness and simplicity. It is expected to become the main technical route for the future advanced ship nuclear power platform. The printed circuit heat exchanger (PCHE) with ultra-high pressure, ultra-compact and ultra-high efficiency typical characteristics is the ideal configuration of the S-CO2 power generation system recuperator. The PCHE numerical analysis model is constructed and the thermal stress field of the PCHE core structure is analyzed by thermal-structural coupling method. The results show that the maximum thermal stress of the PCHE core structure is 117 MPa, which is less than the yield limit of the material and meets the requirement of strength safety. The thermal stress value of most regions in PCHE is less than 78.2MPa. Therefore, the current design scheme has a large safety margin. The PCHE compactness can be further improved by structural parameter optimization.
A practical calibration method of the room type calorimeter for testing the energy efficiency of room air conditioner
Authors: Zhang Haiyun , Hang Chenzhe , Zhongjie Wu , Xu Dinghua
Published: January 2020

The room type calorimeter is generally used as the energy efficiency measurement standard equipment in the air conditioner industry. However, the calibration procedure is not investigated. In this study, based on the empty-load situation of calorimeter, the calibration model is proposed in order to restrain the error of heat balance caused by long-term use. Besides, two new parameters, which are background value of indoor-side and outdoor-side, are presented in accordance with the calibration model. Experiments are designed to obtain these two parameters and three heat leakage coefficients of partition wall, as well as the calibration procedure and application method of the parameters are illustrated. The corrected calorimeter measures ten different window type air conditioners in one year. The results show that the absolute value of heat balance is less than 2% in the cooling capacity range of 2000W∼4500W and 1% in the range of 4500W∼7000W.
Numerical Simulation of Oxy-Fuel Combustion of Predrying Lignite
Authors: Wang Guanyu , Li Xianchun , Zeng Yongjian , Meng Fanrui , Wang Huanran
Published: January 2020

In this paper, the combustion characteristics of lignite with different levels of predrying and the influence of different oxy-fuel concentration on the combustion characteristics of pulverized coal are studied with CFD software. The results show that with the increase of lignite moisture content, the temperature level in the burner decreases gradually, which affects the ignition of pulverized coal and the thermal efficiency of the furnace, and the amount of NO and intermediate products in the furnace also decreases. The flame distance of pulverized coal in oxy-fuel combustion is shortened and the combustion rate is accelerated. The ignition temperature and the production of NO and SO2 are reduced, and the concentration of CO2 can reach more than 90%. The local high temperature will appear in oxy-fuel combustion, and it will increase as the oxygen concentration increases, and the temperature of surrounding flue gas will become more uniform.
Numerical simulation research of influencing factors of fin temperature in finned tube heat exchanger
Authors: Yu Zhiqiang , Chen Yongdong , Wu Xiaohong , Wang Yandong , Cheng Pei , Yu Gaige
Published: January 2020

In the using process of the finned tube, the temperature on the top of the windward face of the fin in the first and second row of finned tube is the highest temperature of finned tube. It restricts and determines the high temperature conditions and application fields of finned tube heat exchanger. This paper establishes the research model of the first row and second row finned tube, to carry out the numerical simulation calculation of the fluid flow and heat transfer of high temperature air flowing through the finned tube and exchanging heat with cooled liquid water, and to research the influence of different tube transverse spacing, fin spacing and other factors on the fluid flow and heat transfer characteristics of finned tube and the highest fin temperature. The air outlet temperature, heat exchange capacity, Nu number, pressure drop and maximum fin temperature are obtained in the conditions of different tube transverse spacing and fin spacing, and the variation characteristic, mechanism and law of temperature field and velocity vector for the finned tube are also gained.
Economic Benefit Evaluation of Waste Heat Recovery in Coal-fired CHP System Based on Exergoeconomic Analysis
Authors: Yu Zaihai , Gao Jintong
Published: January 2020

As one of the main energy-saving measures and an important part of the power industry, CHP (combined heat and power) has achieved rapid development in recent years, which have the advantages of low heat loss, flexible operation mode, and cascade utilization of energy compared with heating boilers and traditional power plants. However, there is a lack of reasonable evaluation of CHP systems, due to the difference in energy quality of heat and electricity. It is urgent to establish considerable and reasonable evaluation indexes of CHP systems. In addition, in the actual operation of CHP plant, a large amount of waste heat is released into the environment, and there is still room for further improvement in the waste heat utilization. In this paper, an exergoeconomic analysis model of CHP system with circulating fluidized bed boiler is established, and the economic benefits of waste heat recovery in CHP systems are studied. After the application of waste heat recovery, the system exergy efficiency increased from 32.94% to 34.14%. The unit exergoeconomic cost of electricity and process steam did not change much, but the unit exergoeconomic cost of heating decreased by 17.1%, which indicates the economic benefits of waste heat recovery.
Failure Analysis of SA-213TP347H High-temperature Reheater of 600 MW Supercritical Boiler
Authors: Wang Jia’an , He Jun
Published: January 2020

Failure analysis of SA-213TP347H steel tube for high-temperature reheater of 600MW supercritical boiler was studied by means of macroscopic analysis, chemical composition, mechanical properties, microstructure, scanning electron microscopy and energy spectrum analysis. The results show that the chemical composition, hardness and strength of the tube samples meet the limit of ASTM A213/A213M standard. The microstructure of tube-burst sample is austenite, there are some precipitates containing Cr and Nb element at the grain boundaries. The test results for the spare part sample near elbow show that the hardness exceeds the limit of SA-213TP347H steel, there are a lot of slip lines and some non-metallic inclusions containing S in the microstructure. It is concluded that solid solution treatment missing in its manufacturing is the main reasons for the fracture, which makes Cr precipitate on the grain boundary and form the Cr-depleted zone, which is easy to cause intergranular stress corrosion and lead to the tube burst.
Preparation and Properties of UV Irradiation Modified ZnO-HA Coating on the Biomedical Magnesium Alloys
Authors: Sun Jin’e , Liu Jie , Niu Zhanxiang , Chi Meizheng , Peng Xuecheng , Yang Yong , Lin Qihui
Published: January 2020

In order to improve the corrosion resistance of magnesium alloys, ZnO-HA coating was prepared on the surface of magnesium alloys by using ultraviolet (UV) irradiation and hydrothermal method. The effects of ultraviolet irradiation time on the microstructure, the electrochemical properties and corrosion resistance of ZnO-HA coating were studied. The results indicated that the ZnO-HA coating obtained by 24 h of UV irradiation combined hydrothermal method was dense and uniform, without any cracks, and it was mainly composed of nanoparticle-like HA and flake-like ZnO. Electrochemical properties and corrosion resistance of ZnO-HA coated magnesium alloys were studied in simulated body fluid (SBF). Compared with the bare magnesium alloys, the coated magnesium alloys have good corrosion resistance. In vitro immersion experiments, ZnO-HA coating could provide good protection for the magnesium alloys substrate, indicating that ZnO-HA coating prepared by UV irradiation combined hydrothermal method can be used as a potential modified biomaterial for magnesium alloys.
Using KH590-Polybutadiene as the New Compatilizer to Improve Carbon Black / Ethylene-Propylene-Diene Terpolymer Composites
Authors: Wu Weili , Yu Bowen
Published: January 2020

Rubber materials could be widely used with the reinforcement of inorganic materials, the combination of inorganic materials and rubber needs compatilizer that play an important role in the polymeric composites. The ethylene-propylene-diene terpolymer (EPDM) has considerable radiation stability for gamma or neutron radiation, so it can be applied to cable insulating materials. The EPDM has to be reinforced with carbon black (CB) of inorganic fillers, which are hardly compatible with the EPDM matrix due to EPDM saturated bonds. In this work, The EPDM matrix modified with (3-Mercaptopropyl) trimethoxysilane (KH590)-polybutadiene (KHBR) was studied in details, and the changes in the mechanical, thermal and rheological properties and curing kinetics were investigated by tensile tests, dynamic thermal mechanical analysis (DMA), thermogravimetric analysis (TG), differential scanning calorimetry (DSC) and moving die rheometer (MDR). The results showed that the addition of KHBR improved the mechanical and thermal properties of the EPDM, and the optimized content was 2.5%.
Design and Research of Convenient Cantilever-Unloading Bracket for Antenna
Authors: Yang Chunsheng , Xu Yiliu , Lu Yi , Wang Yu , Xue Feng , Ren Zhenyue
Published: January 2020

In spacecraft assembly integration and test, zero gravity unloading of antenna is necessary during antenna deployment/closure test. To meet the requirement of antenna unloading condition in EMC test stage, a convenient cantilever type universal antenna unloading bracket is designed. The system consists of the main body of the cantilever device, the first-stage arm, the second-stage arm and the pulley system. Through analysis and calculation, the system can meet the space requirement, friction resistance requirement, strength and deformation limitation in the unloading process. It can provide technical reference and basis for zero gravity deploy ment/closure test for various surface antennas of spacecraft in the assembly process.
Incidence, determinants and consequences of delirium in older patients after transcatheter aortic valve implantation
Authors: Goudzwaard Jeannette A , de Ronde-Tillmans Marjo J A G , de Jager Tom A J , Lenzen Mattie J , Nuis Rutger-Jan , van Mieghem Nicolas M , Daemen Joost , de Jaegere Peter P T , Mattace-Raso Francesco U S
Published: January 2020

Background

delirium is an event leading to negative health outcomes and increased mortality in patients. The aim of this study is to investigate the incidence, determinants and consequences of post-operative delirium (POD) in older patients undergoing transcatheter aortic valve implantation (TAVI).

Methods

The TAVI Care and Cure program is a prospective, observational registry in patients referred for TAVI at Erasmus University Medical Centre. The presence of delirium was evaluated by daily clinical assessment by a geriatrician pre- and up to 3 days post-TAVI. Mortality data were obtained from the Dutch Civil Registry.

Results

A total of 543 patients underwent TAVI between January 2014 and December 2017. Overall, the incidence of POD was 14% (75/543 patients) but declined from 18% in 2014 to 7% in 2017 (P = 0.009). Patients who developed POD were older (81.9 ± 5.8 versus 78.6 ± 8.3 years, P < 0.001), had higher prevalence of renal dysfunction and prior stroke (54% versus 40%, P = 0.02; 31% versus 18%, P = 0.01) and were more often frail (32% versus 25%, P = 0.02). From a procedural perspective, general anesthesia (odds ratios (OR), 2.31; 95% CI, 1.40–3.83; P = 0.001), non-transfemoral access (OR, 2.37; 95% CI, 1.20–4.70; P = 0.01) and longer procedural time (OR, 1.01; 95% CI, 1.01–1.02; P < 0.001) were significantly associated with POD. One-year survival rate was 68% among patients who had suffered a POD and was 85% in patients without a POD (hazard ratio’s 1.8 (95% CI 1.01–3.10), P = 0.045).

Conclusion

POD frequently occurs after TAVI and is associated with increased mortality. It might be speculated that patient selection and the minimalistic approach of TAVI may reduce the frequency of delirium.
Fiscal Incentives in Law Enforcement
Authors: Harvey Anna
Published: January 2020

In recent years, numerous observers have raised concerns about “policing for profit,” or the deployment of law enforcement resources to raise revenue rather than to provide public safety. However, identifying the causal effects of fiscal incentives on law enforcement behavior has remained elusive. In a regression discontinuity design implemented on traffic citation and accident data from Saskatchewan, Canada between 1995 and 2016, a fiscal rule reducing by 75% the share of traffic fine revenue captured by the province in towns above 500 in 1996 population is associated with increased rates of accidents, accident-involved vehicles, accident costs, and accident-related injuries in towns just above this threshold, relative to towns just below the threshold. Further, cited drivers in towns just below this threshold are given fewer days to pay their fines and are less likely to pay their fines on time, leading to higher risks of late fees and license suspensions. These findings suggest that fiscal incentives can indeed distort the allocation of law enforcement effort, with distributional consequences for both public safety and economic well-being.
Performance of a Single Layer of Clothing or Gloves to Prevent Dermal Exposure to Pesticides
Authors: Spaan Suzanne , Glass Richard , Goede Henk , Ruiter Sander , Gerritsen-Ebben Rianda
Published: January 2020

The suitability, availability, and use of protective clothing are critical factors determining the actual dermal exposure (ADE) of operators and workers to pesticides. A realistic assessment of occupational exposure to pesticides requires information about the performance of protective clothing during everyday use. In this study, the performance of clothing or gloves has been investigated based on available dermal exposure data in order to provide recommendations for default protection factors that can be used in regulatory exposure assessments. Suitable dermal exposure data from available exposure databases were collated and analysed. The data that met the selection criteria for the analysis of the performance of protective clothing comprised studies in which protective clothing like cotton coveralls, cotton clothing, polyester–cotton coveralls, Sontara coveralls, Tyvek coveralls, butyl/neoprene gloves, latex/PE/vinyl/PVC gloves, or nitrile gloves were worn. Based on available potential and ADE levels, the migration of pesticides through this protective clothing was estimated. Evaluation of exposure data showed that on average only 2.3–2.6% of the pesticides present on the outside of the clothing or gloves migrated through the garments, although there was a large variation with migration up to 99%. Forearms, legs, and chest areas of the clothing tended to have the greatest migration of pesticides. Caution is needed in the selection of the appropriate protection offered protective clothing for specific situations. This study gives valuable information on the performance of protective clothing, for use in exposure assessment and for default setting in exposure modelling, taking into account the type of clothing or gloves worn. As new data become available, it may be possible to further refine the protection factors offered by different types of clothing or gloves, particularly where a common protocol has been used.
First evidence for a latitudinal body mass effect in extant Crocodylia and the relationships of their reproductive characters
Authors: Lakin Rebecca J , Barrett Paul M , Stevenson Colin , Thomas Robert J , Wills Matthew A
Published: January 2020

Relationships between distribution patterns and body size have been documented in many endothermic taxa. However, the evidence for these trends in ectotherms generally is equivocal, and there have been no studies of effects in crocodylians specifically. Here, we examine the relationship between latitudinal distribution and body mass in 20 extant species of crocodylians, as well as the relationships between seven important reproductive variables. Using phylogenetically independent contrasts to inform generalized linear models, we provide the first evidence of a latitudinal effect on adult female body mass in crocodylians. In addition, we explore the relationships between reproductive variables including egg mass, hatchling mass and clutch size. We report no correlation between egg mass and clutch size, upholding previously reported within-species trends. We also find no evidence of a correlation between measures of latitudinal range and incubation temperature, contrasting with the trends found in turtles.
Guidelines for systematic reporting of sequence alignments
Authors: Vihinen Mauno
Published: January 2020

Bioinformatics methods are increasingly needed and used to analyze and interpret extensive datasets many of which are produced by diverse high-throughput technologies. Unfortunately, it is quite common that published articles do not contain sufficient information to allow the reader to fully comprehend and repeat computational and other studies. Guidelines were developed for reporting studies and results from sequence alignment. Brief and concise checklist of required data items was compiled making it easy to provide necessary details. Implementation of the guidelines requires similar meticulous attitude toward details as other parts of publications. If the journal does not allow reporting full details in the main article, it can be provided in supplementary material. It is important to make the alignments available. Systematic and detailed description of bioinformatics analyses adds to the value of papers and makes it easier for the scientific community to evaluate, understand, verify, and extend the published articles and their results.
Spatial variation in the present-day stress field and tectonic regime of Northeast Tibet from moment tensor solutions of local earthquake data
Authors: Pan Zhengyang , He Jiankun , Shao Zhigang
Published: January 2020

Focal mechanism solutions and their predicted stress pattern can be used to investigate tectonic deformation in seismically active zones and contribute to understanding and constraining the kinematic patterns of the outward growth and uplift of the Tibetan Plateau. Herein, we determined the focal mechanisms of 398 earthquakes in Northeast Tibet recorded by the China National Seismic Network (CNSN) by using the cut-and-paste method. The results show that the earthquakes predominately exhibited thrust and strike-slip faulting mechanisms with very few normal events. We then combined the derived focal mechanisms with global centroid moment tensor (GCMT) catalogue solutions and previously published solutions to predict the regional distribution of the stress field through a damped linear inversion. The inversion results show that most of region is dominated by a thrust faulting regime. From the southern East Kunlun fault in the west to the northern Qilian Mountains along the Altyn Tagh fault (ATF), the maximum compression axis rotates slightly clockwise; farther to the south of the Haiyuan fault in the east, there is an evident clockwise rotation of the maximum compression axis, especially at the eastern end of the Haiyuan fault. In the Qilian Mountains, the axis of the compressive stress orientation approximately trends NE–SW, which does not markedly differ from the direction of India–Eurasia convergence, emphasizing the importance of the compressive stress in reflecting the remote effects of this continental collision. The overall spatial pattern of the principal stress axes is closely consistent with the GPS-derived horizontal surface velocity. A comparison of the stress and strain rate fields demonstrated that the orientations of the crustal stress axes and the surface strain axes were almost identical, which indicates that a diffuse model is more suitable for describing the tectonic characteristics of Northeast Tibet. Additionally, the compressive stress orientation rotated to ENE–WSW in the northern Qilian Mountains along the ATF and to ENE–WSW or E–W along the eastern part of the Haiyuan fault and its adjacent area to the south, highlighting the occurrence of strain partitioning along large left-lateral strike-slip faults or the lateral variation of crustal strength across these faults. Combining geodetic, geological and seismological results, we suggest that a hybrid model incorporating both the diffuse model associated with shortening and thickening of the upper crust and the asthenospheric flow model accounting for the low-velocity zone in the middle-lower crust may reflect the primary mode of crustal deformation in Northeast Tibet.
Antitrust policy in video-on-demand markets: the case of Germany
Authors: Budzinski Oliver , Lindstädt-Dreusicke Nadine
Published: January 2020

The strong growth of different types of online video-on-demand (VoD), ie nonlinear audiovisual media services, including both Paid-for VoD like Amazon Prime and Netflix and Advertised-financed VoD like YouTube increasingly challenges the leading position of “traditional” (terrestrial, cable, satellite) television, ie linear audiovisual media services. Competition policy decisions in such dynamic markets are always particularly challenging. The German competition authority was presented such a challenge when, at the beginning of the 2010s, German television providers sought to enter online VoD markets with the help of cooperative portals. We review the antitrust concerns that were raised back then in an ex post analysis. We derive four aspects, in which the previous antitrust analysis cannot be upheld from today’s perspective. First, relevant implications of modern platform economics were neglected. Secondly, some inconsistencies in the assessment of the two projects appear to be inappropriate. Thirdly, the emerging competitive pressure of international VoD providers was strongly underestimated. Fourthly, the question of market power in online advertising markets looks very different at the end of the decade.
Limitations of Free Light Chain Assays caused by the Matrix Effect
Authors: Farnsworth Christopher W , Logsdon Nicole M , Hayes Jennifer E , Rais Rehan , Willrich Maria A , Gronowski Ann M
Published: January 2020

Background

Serum free light chain (FLC) assays are used clinically to measure the concentration of κ and λ FLC in patients with suspected or diagnosed plasma cell proliferative disorders. Previous studies have demonstrated a loss of linearity in low concentration ranges of these assays. We hypothesized that this result could be caused by a matrix effect.

Methods

Recovery studies were performed for κ and λ FLC in both serum and saline using the Freelite assay (Binding Site) on a Cobas c502 system (Roche). Samples were analyzed either at the recommended dilution or undiluted. Follow-up studies were performed in varying matrices ranging from 0% to 100% saline. Retrospective patient data were analyzed to assess the impact on reported κ FLC, λ FLC, and κ/λ ratio.

Results

FLC in a serum matrix demonstrated underrecovery relative to samples diluted in saline for both κ and λ FLC. Of 255 patient samples with λ FLC measured undiluted (λ FLC <6.0 mg/L), an unexpected gap was observed in patient results between 2.0 and 6.0 mg/L. In addition, 23 patients measured serially with λ FLC between 2.0 and 6.0 mg/L demonstrated dramatic changes in κ/λ ratio, with no changes in κ FLC, likely because of the matrix effect.

Conclusions

The κ and λ Freelite assays exhibit a matrix effect when samples are tested undiluted, which has the potential to affect the κ/λ ratio. Consequently, our laboratory has stopped reporting λ FLC <6.0 mg/L.
Summary of the AOAC-Sponsored Workshop Series Related to the Global Understanding of Food Fraud (GUFF): Mobilization of Resources for Food Authenticity Assurance and Food Fraud Prevention and Mitigation
Authors: Godefroy Samuel Benrejeb , Barrere Virginie , Théolier Jérémie , Baker Robert C , Zhang Guangtao , Hamilton Marc , Pellegrino Monique , Byrne Pamela , Ben Embarek Peter
Published: January 2020

Background

Reports of incidents associated with the misrepresentation of food products as well as the adulteration of their composition leading, at times, to significant public health impacts are being recorded.

Objective

This paper aims at summarizing the outputs of three workshops dedicated to the theme “Global Understanding of Food Fraud” (GUFF), held in Quebec City in Canada (April 2017), Beijing in the People’s Republic of China (October 2017) and Dubai in the United Arab Emirates (October 2018).

Method

Based on the contributions made at these workshops, the paper reviews current knowledge related to food fraud shared by experts and stakeholders representing the food industry sector, food regulators both domestically and internationally and scientists from Academia. It also discusses approaches available to the industry across the food supply chain to predict, prevent, and possibly mitigate food fraud, inclusive of targeted and non-targeted methods of analysis.

Results and Conclusions

The paper offers a discussion on areas warranting the mobilization of efforts and resources of the food stakeholder community to reach consistent and accessible guidance on food fraud prevention, validated analytical methods along with an increased emphasis on prevention in food regulatory measures targeting food fraud. Further development is needed to reach consistent and accessible guidance on food fraud prevention, validated analytical methods, along with an emphasis on food fraud prevention.

Highlights

Food fraud is receiving increased attention from consumers, regulators, and industry. International food fraud experts were invited to three workshops. Contributions and conclusions from the workshops are reported and discussed.
Development and Validation of RP-HPLC and an Ecofriendly HPTLC Method for Simultaneous Determination of Felodipine and Metoprolol Succinate, and their Major Metabolites in Human Spiked Plasma
Authors: Emam Aml A , Naguib Ibrahim A , Hassan Eman S , Abdelaleem Eglal A
Published: January 2020

Background

Felodipine is a calcium channel blocker used together with metoprolol succinate for treatment of hypertension.

Objective

Two chromatographic methods were developed for simultaneous determination of felodipine (FEL) and metoprolol succinate (MET), and their major metabolites, dehydrofelodipine and metoprolol acid, respectively.

Methods

The first method was RP-HPLC which comprised separation of the studied components by gradient elution using a Phenomenex C8 column and a mobile phase composed of water (adjusted to pH 3.5 with o-phosphoric acid)–acetonitrile – methanol (45:40:15, by volume) for the first 6 min and (30:60:10, by volume) for the next 4 min at a flow rate of 1 mL/min followed by UV detection of the eluted peaks at 225 nm. The second method was an HPTLC method where separation was achieved using a mobile phase consisting of toluene–ethyl acetate–methanol–ammonia–formic acid (10:5:2.5:0.3:0.1, by volume) and scanning of the separated bands at 225 nm.

Results

Validation of the developed methods was done according to ICH guidelines. Successful application of the developed methods was carried out for determination of the studied drugs in human spiked plasma and in Logimax® tablets.

Conclusions

The developed RP-HPLC and HPTLC methods can be further applied for quality control testing of the studied drugs.

Highlights

RP-HPLC and HPTLC methods for determination of FEL, MET and their major metabolites. The developed methods were successfully applied for determination of FEL and MET in Logimax® tablets.
Determination of Sorbic Acid in Cheese by High Performance Liquid Chromatography
Authors: Wood Jackie E , Gill Brendon D , Gujaran Gaurav D , Indyk Harvey E , White Peter M
Published: January 2020

Background

Sorbic acid (E, E-2, 4-hexadienoic acid) is added as a preservative to cheese because of its fungistatic and antimicrobial activity.

Objective

A facile method for the analysis of sorbic acid that is applicable to sliced processed cheese and grated cheese products.

Method

A cheese sample and dry-ice mixture was blended and sorbic acid was extracted with methanol and analyzed by HPLC-ultraviolet with external standardization. A large sample size was used to overcome sample inhomogeneity due to imprecise sorbic acid addition techniques during production and sorbic acid migration through the fat over time.

Results

The method was shown to be accurate for both processed cheese and grated Cheddar cheese, with acceptable spike recovery (93.7, 103.7%, respectively), and no bias (α = 0.05) against an international reference method (p = 0.59, p = 0.13, respectively) was found. Acceptable precision was confirmed for both processed cheese slices and grated Cheddar cheese, with repeatability of 5.3% and 4.3% relative standard deviation, respectively, and intermediate precision Horwitz ratio values of 1.3 and 1.7 for processed cheese slices and grated Cheddar cheese, respectively. Method detection limit and ruggedness experiments further demonstrated the suitability of this method for routine compliance testing.

Conclusions

A method for high-throughput, routine testing of sorbic acid is described. The method was subjected to single-laboratory validation and was found to be accurate, precise, and fit-for-purpose.
Application of Ribosomal Internal Transcribed Spacer 1, Internal Transcribed Spacer 2, and Large-Subunit D1–D2 Regions as the Genetic Markers to Identify Fungi Isolated from Different Environmental Samples: A Molecular Surveillance Study of Public Health Importance
Authors: Sulaiman Irshad M , Jacobs Emily , Simpson Steven
Published: January 2020

Background

In September 2012, a multistate fungal meningitis outbreak started across 20 states in the United States. It affected 753 individuals and caused 64 deaths who received contaminated spinal injections. In a previous study, we analyzed 26 environmental samples collected from the manufacturing premises of a compounding company to determine the possible cause of an outbreak and identified 14 distinct fungal species.

Objectives

In this follow-up study, we have analyzed 198 environmental samples collected from three additional compounding company premises located in the United States for the presence of pathogenic fungi.

Methods

Environmental swab samples were initially examined by standard microbiological methods. Subsequently, DNA sequencing was performed on all of the 25 recovered fungal isolates at the D1–D2 domain of the large subunit (LSU) ribosomal RNA (rRNA) and the internal transcribed spacer (ITS) regions.

Results

Sequence analysis of the ITS1, ITS2, and LSU rRNA regions confirmed the presence of the following fungal species in the environmental samples analyzed: (i) Pestalotiopsis cocculi from the region Ia; (ii) Epicoccum nigrum and Trichaptum biforme from the region Ib; (iii) Nigrospora sphaerica and Fusarium sp. from the region II; and (iv) Curvularia sp., Fusarium sp., Penicillium sp., and Preussia sp. from the region III. Species identification of 25 recovered fungal isolates matched, in most cases, at 3 sequenced loci (ITS1, ITS2, and LSU).

Highlights

DNA sequencing of ITS1, ITS2, and LSU D1–D2 regions can be used to perform fungal typing and in implementing effective environmental monitoring programs of public health importance.
Development and Validation of Two Chromatographic Methods for Simultaneous Determination and Quantification of Amiloride Hydrochloride, Hydrochlorothiazide, and Their Related Substances, in Pure and Tablet Forms
Authors: Naguib Ibrahim A , Abdelaleem Eglal A , Abdallah Fatma F , Emam Aml A
Published: January 2020

Background

Amiloride hydrochloride (AM) is a potassium sparing diuretic, while hydrochlorothiazide (HCZ) is the protype of thiazide diuretics. The combining of the studied drugs exhibits a synergistic effect. Moreover, HCZ prevents the potassium depletion side effect caused by AM.

Objective

Two accurate and precise simultaneous chromatographic separation methods were promoted and investigated to quantify AM, HCZ, official impurities of HCZ (cholorothiazide and salamide), and the official impurities of AM (methyl 3, 5-diamino-6-chloropyrazine-2-carboxylate).

Methods

The components of the quintuple mixture were quantified by two methods. The first method was high-performance thin layer chromatography (HPTLC), where exemplary separation was achieved on silica gel HPTLC F254 plates at the stationary phase using ethyl acetate–ethanol–ammonia solution (8 + 2 + 0.2, v/v) as a developing system. Scanning of bands at 273 nm was done. The second method was a reversed-phase chromatography (RP-HPLC) method using C18 (4.6 × 100 mm) column and mobile phase comprising 0.1% phosphoric acid solution–acetonitrile (90 + 10, v/v) with UV determination at 273 nm. Adjustment of the flow rate at 1 mL/min and pH at 3.6 was performed.

Results

Regarding RP-HPLC, optimum separation of the quintuple mixture was achieved within just five minutes. According to HPTLC, symmetric and sharp peaks were separated on the resulted chromatogram. Validity of the introduced methods was investigated by applying international conference on harmonization (ICH) guidelines.

Conclusions

The methods were successfully applied for assays of the studied drugs in their pure and tablet forms. No significant difference was revealed through application of statistical comparison between results of the suggested methods and those of the reported method regarding both accuracy and precision.
Herbs and Medicinal Plants in Jordan
Authors: Haddad Moawiya A , Dmour Hanee , Al-Khazaleh Ja'far M , Obeidat Maher , Al-Abbadi Amal , Al-Shadaideh Ahmad N , Al-mazra'awi Mohammad S , Shatnawi Mohamad A , Iommi Candela
Published: January 2020

Background

The presence of phenolic acids in edible products for human consumption is considered in relation to the production of odorant substances, with a variety of different aromas.

Objective

Phenolic substances anthocyanidins, anthocyanins, flavanols, flavones and isoflavones, flavones, flavonols, etc. – are extremely interesting as flavor additives, anti-aging or maturing agents, and color and aroma enhancers.

Method

The connection between flavoring properties on one hand and the presence of phenolic compounds on the other can be discussed in terms of food acceptance by consumers, especially with relation to the “Mediterranean Diet” lifestyle.

Results

The health perspectives of these and other food products related to Mediterranean Diet should be evaluated in the geographical ambit of the Mediterranean Basin, including several particular food and vegetable preparations – herbs and medicinal plants - of the Middle East.

Conclusions

The aim of this paper is to give a presentation on these specialties in relation to Jordan.

Highlights

Medicinal herbs have interesting health properties against digestive problems, parasitic worms, liver diseases, diabetes, skin problems, nervous, cardiocirculatory, and respiratory diseases.
Phenolics in Mediterranean and Middle East Important Fruits
Authors: Haddad Moawiya A , El-Qudah Jafar , Abu-Romman Saeid , Obeidat Maher , Iommi Candela , Jaradat Da’san M M
Published: January 2020

Background

Phenolic compounds (polyphenols) are common plant secondary metabolites playing different roles in plants, and some of these vegetables and correlated fruits—figs, grapes, pomegranates, olives, date palms, etc.—contain remarkable and diversified amounts of these substances. In addition, polyphenols are reported to show positive effects for human health, because of their antioxidant behavior. Figs are an excellent source of polyphenols with highest concentrations of proanthocyanidins. Actually, figs contain higher amounts of polyphenols than red wine and tea.

Objective

Antioxidant activity of several flavonoids (a group of polyphenols) in figs is higher than that of, vitamin C, glutathione, or vitamin E. Pomegranates contain very high levels of polyphenols as compared to other fruits and vegetables. It is used in folklore medicine for the treatment of various diseases, such as hepatic damage, snakebite, ulcer, etc.

Method

The health-positive potential of pomegranate fruit has been mainly attributed to ellagitannins, the predominant class of phenolics in pomegoxidation.

Results

The chief phenolic compound found in fresh olive is the bitter secoiridoid oleuropein..

Conclusions

Processing of table olive decreases levels of oleuropein with correlated increases in the hydrolysis of hydroxytyrosol and tyrosol. Many of the health benefits reported for olives are thought to be associated with the levels of hydroxytyrosol. Date palm represents a staple food in most of the Arabian countries and is commonly consumed in several parts of the world.

Highlights

Numerous researches revealed the antibacterial, anti-hyperlipidemic, hepatoprotective, antimutagenic, and nephroprotective activity of date fruits, with reported anticancer and anti-fungal features.
Phenolic Substances in Foods and Anticarcinogenic Properties: A Public Health Perspective
Authors: Laganà Pasqualina , Coniglio Maria Anna , Fiorino Marco , Delgado Amélia Martins , Chammen Nadia , Issaoui Manel , Gambuzza Maria E , Iommi Candela , Soraci Luca , Haddad Moawiya A , Delia Santi
Published: January 2020

The interest in polyphenols from vegetable sources has been progressively increased because of the demonstrated correlation between their abundance in certain foods or food preparations of traditional importance and heritage, and the answer of anti-inflammatory strategies in hospitalized patients in the presence of polypehnol-rich foods (as a complementary therapy). Consequently, research involving the accessory role of polyphenols as anti-tumoral aids have been carried out with the aim of finding new additional strategies. The purpose of this paper to evaluate the role of phenolic compounds in foods with reference to health effects for human beings. The importance of these molecules has been evaluated by the health and safety perspectives in terms of: fight to cardiovascular diseases; prevention of chronic-degenerative disorders; general antioxidant properties; and anticarcinogenic features. Moreover, the role of polyphenols-rich foods as anticancer agents has been discussed with relation to two distinct “action plans” on the public hygiene level: the promotion of human health on the one side (for non-hospitalized and normal subjects), and reliable contrasting strategies in cancer patients.