bluuebunny/crossref_metadata_2025 huggingface dataset:
Flexural behavior of continuous beams consisting of normal concrete and SIFCON under static and repeated loads
Authors: Abeer S Z , Dawood M B , Ghalib M H
Published: July 2020

In this paper Slurry Infiltrated Fiber Concrete (SIFCON) has been used at plastic hinge locations to fix the ductility problem of continuous reinforced concrete beams. The use of SIFCON in compression parts of plastic hinge zones for continuous beam has been experimentally studied under both static and repeated loads. Six continuous beams with full scale have been tested; two with normal concrete totally and four with SIFCON at compression parts of plastic hinge locations. Three fraction volumes of fibers (Vf) % have been considered, 7%, 9% and 11%. Also, the influence of using SIFCON parts on redistribution of bending moment for continuous beams is investigated. It was noticed that, in all the reinforcement concrete beams, the using of SIFCON increased the capacity and ductility of the samples at same time. The improvement in the flexural capacity, the toughness and the moment redistribution for continuous beams could reach as high as 20%, 20% and 104% respectively. In addition, it was found that the reduction in flexural strength of composite continuous beam when it exposures to repeated loads was about 0.6% in comparison with that under static loads.
Morphologic and Engineering Characteristics of Watersheds (A Case Study: East Wasit Watersheds that Feed the Al-Shewicha Trough - Iraq)
Authors: Shamkhi Mohammed S. , Ridha Azeez Jasim Mohammed , Abdul-Sahib Ali A.
Published: July 2020

The Al-Shewicha Trough represents a real flood hazard to Kut City (capital of Wasit Province, Iraq) as well as to the other cities along the Tigris River downstream Kut Barrage, especially heavy monsoon years. Under the acute lack of water resources around the world, many modern techniques in unconventional innovative water resources management were developed. In this study, ArcGIS was used in the morphologic analysis of six river basins which represent the main sources of feed for the Al-Shewicha Trough. The results show that the high value of the greatest length of a basin 1,5 and 6 indicate that these watersheds have high value of concentration time (tc) which delays the peak flow. All basins consisted of very coarse and permeable subsurface strata, and were of coarse texture. Circularity ratio Form factor and elongation ratio shows an elongated shape of all basins with lower peak flow and long duration. Analyses of soil data demonstrate that the soil type that covers a large area is loam soil within the hydrologic soil group type B, which indicates that all basins have low permeability and high runoff. The most predominant land use was bare soil and all basins have a covering of poor vegetation which highlights the basins that are most susceptible to erosion, thus resulting in the generation of higher sedimentation.
Automatic Medical Images Segmentation Based on Deep Learning Networks
Authors: Shadeed Ghada A. , Tawfeeq Mohammed A. , Mahmoud Sawsan M.
Published: July 2020

In recent years, radiography systems have become more used in medical fields, where they are used for diagnosing many diseases. The size of the radiographs differs, as well as the size of the body parts for each patient. So many researchers crop the radiographs manually to facilitate the diagnosis and make it more reliable. Currently, the trend toward deep learning was commended where the deep learning proved its effectiveness in many fields, especially in the medical field, in which it achieves good results in diagnosing the most types of diseases. Deep learning performance increases significantly when the training process is focused on the region of interest. In this paper, segmentation is implemented by used deep learning model on the thoracic region of the radiograph in order to be cropped later. The proposed model provided automatic cropping of the radiographs where a semantic segmentation network is provided by Vgg19 model. A comparison is done with semantic segmentation network provided by Vgg16. The segmentation based on Vgg19 model outperforms Vgg16 model in cropping Chest x-ray images dataset automatically and quickly.
Dark current analysis of p-i-n NiO/BiTiO3/ZnO thin film heterojunction diode
Authors: Hassan Alaa K , Ali Ghusoon M
Published: July 2020

Dark current analysis of fabricated NiO/BiTiO3/ZnO heterojunction thin film p-i-n diode is demonstrated in this paper. The diodes layers; p-type NiO, i-type BiTiO3 and n-type ZnO were fabricated by using a sol-gel method on glass substrates. This method is the most practical techniques used for manufacturing the nanostructured thin films of metal oxide and perovskite semiconductors. The electrical characteristics of the vertical p-i-n diode were investigated using current-voltage characterization at room ambient in dark condition. The parameters, for example, threshold voltage, rectifying ratio, ideality factor, junction resistance and leakage current, were extracted from the measured data. The turn on voltage, ideality factor, saturation current, junction series resistance, and junction shunt resistance were estimated to be 0.6 V, 6.1, 8×10-7 A, 40 Ω and 760 Ω, respectively. The effect of post-fabrication heat treatments on electrical properties has been studied. The optimum temperature at 100°C that improves the device performance. The performance enhancement attributed to the interface improvement of the between the aluminum contact and p-i-n thin films. With respect as-deposited p-i-n devices, the heat-treated diodes performance parameters such as threshold voltage, ideality factor and leakage current of devices are found to improve by 5%, 47.3%, and 63.3%, respectively. The rectification performance of the device was 13.6 at 100°C and degrades after the temperature reached 125°C attributed to new material phases appears at interfaces.
Thin Film Transistors p-type Depletion Mode based on Nickel-doped Zinc Oxide
Authors: Mirza Ali Ahmed , Ali Ghusoon M.
Published: July 2020

In this work, Nickel-doped Zinc oxide (Ni:ZnO) thin film transistors (TFTs) p-type depletion mode were fabricated with different channel lengths. Channel lengths for TFTs were 50 μm, 70 μm and 100 μm. Ni:ZnO thin films deposited by hydrothermal technique The X-ray Diffraction (XRD) was used to examine the structural analytic of the prepared thin films. The diffraction peaks of prepared Ni:ZnO thin films are fairly matching with the hexagonal wurtzite ZnO structure with the preferred orientation (002) plane. The Scanning Electron Microscopy (SEM) with Atomic Force Microscopy (AFM) were used to characterize the surface morphologies of the fabricated thin films and study them. The SEM images confirm nanorods nanostructures. Hall Effect measurements reveal that the fabricated thin film is p-type. The characterization of Ni:ZnO TFTs p-type depletion mode was investigated by transfer (IDS–VGS) characteristics. The threshold voltage (VTh), subthreshold-swing (S.S), the on-off current ratio (ION/OFF) and the mobility carrier (saturation regime) were calculated. The 50μm Ni:ZnO TFT shows better performance based on device carrier mobility and highest ION/OFF ratio.
Recycling wastepaper papercrete to produce green concrete
Authors: Zubaidi Aseel B Al , Ahmedizat Shatha R , Al-Tabbakh Ahmed A
Published: July 2020

This research studies using wastepaper as a replacement material in concrete blends. A concrete mollified wastepaper created via adding wastepaper as partial replacement through cement’s weight. Furthermore, it might be considered as eco-friendly, construction material was reduced amount of wastepaper. Inherent strength was gained because of the presence regarding the hydrogen chains in wastepaper’s microstructure. Papercrete has less costs in comparison to substitute building construction materials, energy absorption. Sound absorption and low thermal insulation were enhanced by papercrete. The different presents of wastepaper used after treating namely 0%, 5%, 7% in addition to 10% through partial replacement that is related to the cement’s weight for studying concrete blend’s mechanized properties like flexural tensile strength, split strength, compressive strength and put to comparison with the conventional mix. The results have specified that the flexural tensile strength, splitting strength as well as compressive strength decreased as the wastepaper’s content increased.
Analysis of Refractory Materials on Example of Experience of The Oxygen-Converter Department (JSC AMT, Temirtau, Kazakhstan)
Authors: Fatehy Aseel Nadhem , Meteab Mohammed Mhana , Ahmed Ashraf Abdullah
Published: July 2020

The article deals with the problems associated to the use of refractories in the metallurgical industry. In connecting with that, brief information about the refractories, their composition and classification was presented and as a practical example the operating experience of refractories in the oxygen-converter department of metallurgical plant was considered. Furthermore, steel teeming ladle as technological equipment which accounts for 30 … 35% of refractories was studied and as a result, a lining project reinforcing layer 300-t teeming ladles made of refractories with a curve form has been designed. The project successfully passed the experimental stage.
Performance of Dual Phase non-Newtonian Fluid in an Eccentric Annuli with Rotation of Inner Cylinder
Authors: Jassim L , Falih A H , Aldeen A S
Published: July 2020

The eccentric annular flow is a flow with special considerations; it forms a vital part of practical industrial flow analysis. In this work eccentric, dual phase flow through horizontal wells are simulated with the help of CFD. In horizontal annuli, flow occurs in an adverse pressure gradient condition, that makes the particle inside it susceptible to reversed flow. Thus the flow has to be analyzed in a three dimensional manner. Moreover, the non-Newtonian behavior of the fluid makes the problem really challenging in numerical and physical aspects. The results of this work clarify the relationship between different flow characteristics with the speed of inner wall rotation. The flow characteristics include swirl of flow, wall shear stress, and axial velocity.
Study the Thermal Properties of PVP/CuNPs Composite Prepared by Different Concentrations
Authors: Dhiaa Asmaa H. , Taher Ahmed A. , Diwan Abbas A. , Thahab S.M. , Azez Rana J.
Published: July 2020

In this paper, copper nanoparticles (CuNPs) with a particle size of 40 nm were used to prepare a copper paste by using a liquid phase reduction method with Poly vinyl pyrrolidone (PVP) aqueous solutions in ethanol with different concentrations of CuNPs. Many thermal properties were characterized such as scanning electron microscopy (SEM), viscosity, thermal conductivity, PVP has properties such as a surface stabilizer, growth modifier, nanoparticle dispersant, and reducing agent. The influence of CuNPs particle volume fraction of (0.1, 0.2, 0.3 and 0.5%) with PVP on the thermal conductivity, pH and viscosity values of CuNPs./PVP were characterized. The experimental data show that the thermal conductivity of composites increases with the increase of filler. The enhancement of thermal conductivity is 62 % at 0.5% of the volume concentration at 25°C from the base PVP colloidal.
Experimental study of Natural composite Material on Acoustic properties
Authors: Kassim Muna S. , Al-Maliki Ammar Fadhil Hussein , Jasim Hadeel Abdulhadi
Published: July 2020

The nature of natural fibers is porous, which is useful feature for sound absorption. These types of materials (natural) are less ecofriendly and ecofriendly. This study deal with the effect of using natural composite material as sound insulation, many types of natural materials with fiber glass had been used in this study, i.e. cotton, wool, fronds and vegetarian fibers with different thicknesses. The study consist of built attest rig to measure the different frequencies and sound waves experimentally to calculate the transmission losses and coefficient of transmission losses that are dialing from function generator use sound pressure level. The best results of transmission losses recorded for the composite materials (Polyester +Random + wool) and (polyester + fiber glass + cotton) in three thickness 6mm, 8mm and 10mm. From other side, the best results of absorption of noise at different frequencies recorded for (polyester + fiber glass + cotton) and (Epoxy + fiber glass + plan fronds) in three thicknesses.
Hydrodynamics Simulation for Air Flow Past Over an SD 2030 Airfoil Using Two Dimensional Model
Authors: Hamzah Dhafer A , Hamza Naseer H , Al-Dawody Mohamed F , Al-Farhany Khaled
Published: July 2020

In the old new present work cares with change of Reynolds number effect on the hydrodynamic characteristics. The different pitch angle is taken to analysis drag, lift, and pressure coefficients. The goal of these parameters is to understand the nature of the flow over the upper surface of the airfoil since the long laminar boundary layer and transition region have a light point for aerodynamics performance assessment. The results indicated that indicated the improvement in performance is parallel in path with the increasing length of the laminar flow region.
An Experimental and Theoretical Study of Forced Convection from a Peltier Thermo-electric Cooling
Authors: Idan Al-Chlaihawi Kadhim K. , Al-Saadi Ahmed , Jabbar Nasr A.
Published: July 2020

An experimental and theoretical study for heat transfer through thermoelectric cooling system in this paper was presented. An experimental work was conducted to evaluate the performance of a thermoelectric module fitted to a sun flower heat sink with a similar sized heat source. The experimental investigation was done to evaluate the effect of TE input voltage, flow rates of cooling air and heat source (heating element) power input on the performance of a thermoelectric cooling system. Four low heating load (1.7, 2.4, 3.6 and 5 W) were used and hot side was fitted to a sunflower heat sink with forced convection. Experimental results show that the increasing of cooling air flow rates improves system performance, while increasing in applied TE voltage leads to deterioration it. The COPmax obtained is about 4.7 at 2V TE voltages and 5W heating load, and then decreased sharply as voltage further increased and reaches 0.13 at 12V. The results of the current study show that all Thermo-electric Cooling system recorded temperatures increase with increasing in heating load at a constant TE voltage and air flow rate. In addition to that the Tc
decreases and Th
increases with the increment of input voltage and that can lead to increase of the air temperature passing over heat sink. TE performance is highly affected by air flow rate. The theoretical result validated experimentally and shows an acceptable agreement between them.
Stability of Emulsions Prepared by Vapor Condensation
Authors: Tudose E T Iacob
Published: July 2020

Emulsions, consisting of a mixture of two immiscible liquids, one dispersed in another, with an added amphiphilic surfactant, have been extensively used in different areas such as cosmetics, pharmaceutics, material synthesis for new applications, for example thermal energy storage, new cooling systems etc. The current study focuses on emulsion preparation using a novel technique[1], namely water vapor condensation on an oil-surfactant layer containing one or two surfactants. The method was incompletely investigated previosly, thus experiments were initiated in order to assess the emulsion stability for different working conditions. Two distinctive configurations were experimentally studied, one, with an adiabatic, constant room temperature bottom and another, with a high, constant temperature bottom. A mixture of two surfactants, Tween 80 and Span 80, was used in different ratios, also, the condensation time and the vapor flowrate were varied. The obtained emulsions stabilities were assessed visually and also, by pH measurements, over couple of week time period. The estimated average emulsion particle size was within the microscale range.
Photocatalytic Degradation of Methylene Blue Dye Using TiO2and Fe3O4/SiO2/TiO2as Photocatalysts
Authors: Tarcea C I , Pantilimon C M , Matei E , Predescu A M , Berbecaru A C , Rapa M , Turcanu A , Predescu C
Published: July 2020

This paper is focused on obtained two catalysts such as TiO2nanoparticles and Fe3O4/SiO2/TiO2nanocomposite for adsorption and photocatalytic degradation of methylene blue (MB) dyes from aqueous solution. The morphology, structure and chemical proprieties of synthesized materials were investigated by X-ray diffraction (XRD) analysis, scanning electron microscopy (SEM), N2adsorption-desorption isotherms and Zeta potential. The photocatalytic degradation of methylene blue under UV light in the presence of different synthesized catalysts was analyzed with Spectrometer UV-Vis. The photocatalytic degradation of methylene blue was studies by focusing of photoactivity performance of Fe3O4/SiO2/TiO2in comparation with TiO2. An attempt has been made to study the effect of process parameters through amount of the catalysts and initial concentrations of methylene blue. In all cases was found that the kinetics of the MB photocatalytic degradation under UV light was fitted to the Langmuir–Hinshelwood. Even if the photocatalytic degradation study revealed that Fe3O4/SiO2/TiO2and TiO2degraded about 90 % of methylene blue within 60 min, the magnetic nanocomposite Fe3O4/SiO2/TiO2serves as better catalyst compared with TiO2nanoparticles. An important role in the photocatalytic degradation of MB is adsorption characteristic of TiO2and Fe3O4/SiO2/TiO2surface. The photocatalytic performance of Fe3O4/SiO2/TiO2remained greater than TiO2after 4 cycles of use.
Experimental Study of Thermochemical Treated Biomedical 3D Printed Titanium Alloy Implant
Authors: Kónya J , Kulcsár K
Published: July 2020

For medical and dental individual implants are made by additive technology. The patient-specific usable implant material is the Ti alloy (Grade 23). The used 3D printer do LMF (Laser Metal Fusion) process and melts the metal particle by the laser layer by layer. Surface treatment of implants affects mechanical strength, aesthetic and osseointegration properties [1]. Of these, our study investigates the mechanical strength properties of plasma nitride surface treatment. The plasma nitrided 3D printed biomedical Ti alloy (Ti6Al4V, Grade 23) mechanical properties. The influence of the nitrided layer on tribological behaviour of plasma nitrided film was studied using microhardness tester. The microhardness results pointed out that the surface treatment increased the surface hardness and reduced the plastic deformation of the alloy.
Recycling of Plastic Throughout Pyrolysis and Distillation Process to Recover an Alternative Fuel Sources
Authors: Muzarpar S , Leman A M , Rahman K A , Foudzi M T R M
Published: July 2020

Pyrolysis process is a process whereby plastic undergo the heating process and transform into another type of product either liquid form or waxy form. The basic purposed of the study was to determine the type of product formed from different type of plastic used. From the product collected in pyrolysis process it will undergo a further distillation process to increase the quality of the product. The methods that was involved in the making of the product is by using pyrolysis process, distillation process whereby a few product are derived. For pyrolysis process, plastic is heated until vaporized and the vapor is collected and condense to collect the product, while for the distillation process the separation process is done to separate the product according to its boiling point. For data collection, every sample is tested by using the Fourier Transform Infrared Spectroscopy (FTIR) and the bomb calorimeter for its calorific value. From three types of plastic used which is polystyrene, polyethylene, and polyethylene tetraphlate the most suitable type of plastic is polystyrene due to its product which is in liquid form. The distillation process will give three end product which is similar to commercial petrol, diesel and high density oil.
Microstructural Analysis of Multiple Layer Depositions on Cast Iron Using the Electrospark Deposition Method
Authors: Perju M C , Nejneru C , Vizureanu P , Burduhos Nergis D D , Sandu A V
Published: July 2020

The present article is focused on the obtaining of a thin layer system on Fe-C alloys by deposition of 3 successive layers with several electrodes. These layers offer to the material a broad range of enhanced properties as: mechanical resistance, surface hardness, compression behavior and a martensitic structure of the carbides, which reduce the effect of the wear, having positive results on the life-cycle of the product. The principle of the hardening consists in an electrical discharge by spark on which the action of the rectified current impulse transfers material from the electrode, considered cathode to the surface of the material which is the anode. This material reacts chemically with the nitrogen, from the atmosphere, with carbon and with support material, forming a diffusion layer, resistant to wear.
Laser Induced Dyeing (LID) with Reactive Blue 21 on Hemp Fibers
Authors: Cocean A , Cocean I , Postolachi C , Pricop D , Husanu F , Gurlui S
Published: July 2020

Effects of 532 nm and 320 mJ laser beam on aqueous solution of Reactive Blue 21 (RB21), a copper based on reactive dye, have been studied in both presence and absence of garnet gemstone with the aim to receive a proper coating of the hemp fibers contained in the yarns of a woven texture while reducing the dyeing time compared to the classic exhaustion dyeing method. Results show that both laser beam and garnet influenced the dyeing process with RB21, enhancing the absorption and reaction of RB21 with the composite structured hemp fibers, effect observed in the color intensities for all samples measured with the grayscale. The best results are noticed for laser effects in presence of garnet gemstone when highest coating is achieved among all samples, and the process is 11 times shorter than the classical exhausting method. Compared FTIR and UV-VIS spectra of initial dyestuff and residual dyestuff isolated from the wastewaters offered information about dyestuff exhaustion process under garnet and/or laser influence. Laser Induced Fluorescence completed the study with the information about RB21 behavior under UV laser beam of 362 nm.
Influencing Factors on Premature Fracture of Cast Iron Support of Electric Motor in Aluminium Rolling Line
Authors: Preda F , Riposan I , Stan S
Published: July 2020

There is a limited increase in the temperature of the cast iron supports during rolling (up to 30…50°C), but there is a wide range of vibration level (2.6 - 4.4 mm/s) representing 58-98% (75-80% as medium values) from the maximum admitted level (4.5 mm/s, ISO 10816). The maximum level of vibration is identified in the area where a fan is installed to cool the electric motor. In all electric motor types it appears a difference between several measurements, which highlights the appearance of various conditions in the rolling process, or in the quality of the cast iron support. The fracture of the support takes place predominantly in the area of fixing it with a screw. The cracks connect firstly the areas with casting defects (inclusions, pinholes, shrinkage and micro-shrinkages), but also coarse graphite particles (Kish or Type C-ASTM, spiky graphite) or undercooled graphite morphologies (Type-D ASTM). Lamellar graphite cast irons (traditionally used in this domain) are characterized by a low level of fracture resistance but high vibration damping capacity due to which it is necessary to make parts without casting defects and with a controlled graphite phase (high amount of graphite, graphite Type-A ASTM, without undercooled graphite), usually obtained through high performance inoculation [1,2].
Transfer Processes at the Manufacture of Metal Matrix Composite Materials
Authors: Florea R M
Published: July 2020

The main elements of composite materials technological design consist of choosing the appropriate matrix/reinforcement systems and optimal thermodynamic conditions for ensuring compatibility during processing and operation. Composite material properties depend on the volumetric characteristics of components as well on the intensity of links between these components. Initially, the mass transfer takes place under unstable conditions in the liquid matrix and at the solid/liquid interface, and finally, after casting or infiltration, stationary. Modelling of reinforcement elements transfer from gas to liquid is based on total variation of transfer energy or on the variation of the amount of the forces acting on the reinforcement. Once the basis of the models investigated and of the actual model proposed are analyzed, the densities influences, particles granulations, liquid viscosity, thermal conductivities, the energies at liquid/reinforcement interface and critical speeds of reinforcement elements, transfer from liquid to solid.
Improvement of Microplastics Separation from Synthetic Samples – A Key Step for Their Analysis
Authors: Ciobotaru I-E , Marcu E , Maria C , Ivanov A A , Savin I , Moncea A , Tociu C , Deák Gy
Published: July 2020

Identification of microplastics from the environment is a challenge mostly due to the complex nature and behavior of samples and lack of an efficient separation method. This paper approaches the issue of microplastics separation as determining step of their analysis. The separation of two types of commercial plastics from synthetic samples was investigated, namely polyethylene terephthalate (PET) and high density polyethylene (HDPE). Subsequent filtration through filters with different porosities was tested and improved by adding a surfactant in the extraction medium. For the qualitative analysis of microplastic, optical microscopy and laser-granulometry were employed. The results proved the separation of microplastics from the samples and showed a distribution between 10-100 μm for PET and 10-200 μm for HDPE. These results provide basis for the efficient microplastics separation and further quantitative analysis from more complex samples, such as environmental samples.
Optimized Conversion of Nyamplung Seeds Oil to Biodiesel Using Box-Behnken Response Surface Methodology (RSM)
Authors: Ilham Z , Mansor M R A
Published: July 2020

This research is carried out for optimization of transesterification reaction parameters to convert oil from Nyamplung (Calophyllum inophyllum) seeds into biodiesel. Calophyllum inophyllum seeds were normally left unused due to the toxicity of calophynic acid in the unrefined extracted oil. The optimal variables (parameters) for converting Calophyllum inophyllum seeds oil into biodiesel were found to be at a methanol: oil ratio (6 to 1), 67.5 °C temperature, 1 wt% catalyst and agitation rate of 750 (rpm). The biodiesel yield obtained (93.01 wt%). The results also indicated that Calophyllum inophyllum methyl esters (CIME) fuel properties such as kinematic viscosity 4.55 mm2/s acid value 0.027 mg KOH/g, cloud point 3 °C, pour point 1 °C, flash Point 161 °C, cetane index 49 min and density of 856 kg/m3 conformed with the international standard specifications except for the oxidation stability, which was at 4.38 hour. In addition, ANOVA of the developed model displayed presentation (R2 0.99). Calophyllum inophyllum seeds oil could be a suitable non-edible feedstock for biodiesel, especially in the South East Asian region.
Comparative Study on the Characteristics of Silicone Elastomers used in Dental Impression Techniques
Authors: Gradinaru I , Ciubotaru B-I , Zaltariov M-F , Cazacu M
Published: July 2020

Even through nowadays technology and robotics seem to have taken a front seat on the medical field, there are still conventional methods being used in dental medicine, especially related to impression techniques. Elastomers such as silicone rubbers are widely used as impression materials for their suitable properties and behavior in dentistry. As the long-term success of the prosthetic therapy relies on the impression stage, it is important to know both the advantages and disadvantages of such materials. Nowadays in vitro and in vivo studies are being conducted to establish the precision and accuracy of these materials. In this study we report comparatively a number of characteristics determined by us under identical conditions for four such materials. Structural studies (through IR and XRF), morphology (through AFM and SEM) and surface (water contact angle) were performed. Based on the results obtained we can identify more or less significant differences between some characteristics, which could help to indicate the right material depending on the case requirements.
Recycling of Aqueous Phase from Hydrothermal Liquefaction and Municipal Wastewater by Microalgae
Authors: Chernova N , Kiseleva S , Vlaskin M , Grigorenko A
Published: July 2020

The search for alternatives to hydrocarbon fuels remains an actual task. Microalgae (MA) as raw material for the production of biofuel remain an urgent object of research among other types of biomass, and the cultivation of MA is constantly growing. One of the promising technologies for biofuel production from MA is hydrothermal liquefaction (HTL) that allows processing wet biomass and turning all carbon-containing components (lipids, carbohydrates, proteins) into fuel. However, the hydrothermal liquefaction process leads to the formation of a significant amount of the aqueous phase, which is a by-product with low energy value and also needs to be processed. It is important to consider the possibility of using the aqueous phase after HTL, as well as municipal wastewater, for the cultivation of MA in combination with the production of biofuels. The MA strains capable to grow in a dilute aqueous phase after HTL (Galdieria sulphuraria rsemsu G-1, Chlorella vulgaris rsemsu Chv-20/11-Ps, Arthrospira platensis rsemsu Bios) and in wastewater (Arthrospira platensis rsemsu Bios, Chlorella ellipsoidea rsemsu Chl-el) were experimentally selected from collection of RSE Laboratory at LMSU. The article is devoted to the experimental study of the degree of nutrients utilization by MA from wastewater and an HTL-aqueous phase.
Study of Physico-Chemical Characteristics of Some Major Urban Air Pollutants
Authors: Garofalide S , Diaconu M , Cocean I , Cocean A , Pelin V , Gurlui S , Leontie L
Published: July 2020

Urban air/environmental pollution as a major concern of contemporary civilization, substantially affecting the health of the residents, requires identification of both physico-chemical specificity and generating sources. Particle matter (PM) monitored in the atmosphere should be associated to their chemical composition that allows identification of sources as enhancement contributor and sinks as mitigation factor but also as possible spreading agent as it has been reported in rain fall for some of the pollutants cathegories. After a number of episodes of increased amounts of measured PM 2.5 and PM 10, considerable dust deposits on cars were collected and SEM-EDX analyses were performed, showing the agglomerated morphology and elemental composition of the dust. Sodium aluminate and calcium chloride were identified as major contributors to the dust composition. Such chemical components may end-up into the water supply and tab water as previously reported affecting the quality of the water. As sources, dust-binding solutions for streets cleaning and/or coagulant agents in constructions are to be considered.
Assessing the Contamination of the Dambovita River Through Heavy Metal Indices
Authors: Dumitru F D , Deák Gy , Moncea M A , Baraitaru A G , Gheorghe P I , Ciobotaru I E
Published: July 2020

The continuous population growth, which leads to increased social and economic development, affects the quality and quantity of the freshwater resources, both directly through changes in landscapes and pollution caused by industrialization, urbanization, and agriculture, as well as indirectly through climate change pressures (such as higher air temperature, drought, frequent extreme precipitation events). Within this study, the heavy metal contamination of Dambovita River was assessed, as it is the main drinking water source for the city of Bucharest. Thus, surface water samples and sediments were collected from four sampling sites along the Dambovita River within two campaigns, in order to assess the seasonal fluctuations. The heavy metal pollution index (HPI) together with the metal index (MI) of the collected water samples were calculated for cadmium, nickel and lead, for each sampling site. Additionally, in order to establish the potential ecological risk index, the contamination factors and potential ecological risk factors were assessed considering each of the monitored heavy metals (Cd, Ni and Pb). The results showed that the HPI values were below the critical pollution index value of 100, along with MI values below 1. Also, the sediment analyses further confirmed that all the sampling sites can be classified with low to medium levels of potential ecological risk.
Experimental Research on the Behaviour of the Systems for Ventilated Facades, Exposed to the Fire Action
Authors: Dragne H , Simion A , Stoica D
Published: July 2020

When establishing the constructive structures that must reach the required levels of fire performance, one must start from the fact that the fire is an accident. The structures must remain viable for the normal fire time considered. The behaviour of the construction to the fire is dependent, besides other factors, on the contribution to the fire of the elements and parts of the construction, of the materials and products for the construction, as well as on the fire resistance of some of them. Due to the fact that the initiation and evolution of the fires is different, it was imposed that the determination of the fire behaviour of the constructions and the materials that enter their composition should be done under specified conditions, by exposing them to a specified ignition source, in a good context.
Relationship Between Arterial Stiffness and New-Onset Diabetes Mellitus in Hypertensive Population
Authors: Wang Guo-dong , Sun Yue-qiu , Wang Jin-mei , Zhang Shu-an , Wang Ying-guang , Chen Shuo-hua , Wu Shou-ling , Huang Zhe
Published: July 2020

Background

To investigate the relationship between arterial stiffness and new-onset diabetes mellitus in hypertensive population.

Methods

A total of 8,061 hypertensive and nondiabetic employees who participated in the yearly physical examination (2010–2015) of the Kailuan study were enrolled into the present study. Arterial stiffness was evaluated by brachial-ankle pulse wave velocity (baPWV). Baseline was set at the first baPWV measurement, while follow-up ended at the first incident of diabetes mellitus or until the last examination (2016–2017). According to baPWV quartile, the effect of baPWV on new-onset diabetes mellitus was analyzed by Cox proportional hazard model, and a sensitivity test was analyzed by body mass index stratification.

Results

The mean follow-up time was (4.2 ± 2.1) years. During the follow-up period, 874 (10.8%) participants developed diabetes, with an average incidence rate of 25.7 per 1,000 person-years. The incidence rate (per 1,000 person-years) of new-onset diabetes in the first to fourth quartile of baPWV was 14.6, 23.8, 27.2, and 37.7, respectively (P < 0.001). Compared with the first quartile of baPWV, after adjustment for age, gender, mean arterial pressure, baseline fasting glucose, hypersensitive C-reactive protein, and other confounding factors, the HR and 95% confidence interval for new-onset diabetes of the second, third, and fourth quartile were 1.57 (1.24–1.98), 1.74 (1.37–2.20), and 2.38 (1.87–3.03), respectively. For each standard deviation increase of baPWV, the HR and 95% confidence interval were 1.32 (1.24–1.42).

Conclusions

Arterial stiffness is associated with new-onset diabetes mellitus in the hypertensive population.
The Location Learning Test-Revised is associated with informant-reported everyday functioning in a sample of community-dwelling older adults
Authors: Thompson Jennifer L , Bucks Romola S , Weinborn Michael , Woods Steven Paul
Published: July 2020

Objective

Object location learning and memory may be important for older adults to successfully complete some everyday activities.

Method

This cross-sectional, correlational study investigated the ecological relevance of the Location Learning Test-Revised (LLT-R) in 195 community-dwelling, older adults in Western Australia. The LLT-R assesses object location learning and memory for everyday objects over five learning trials and after a 30-min delay. Knowledgeable informants provided structured ratings of participants’ activities of daily living and memory symptoms.

Results

A greater number of errors on LLT-R total learning trials were associated with mild problems in activities of daily living (particularly in travel and household domains), but not with memory symptoms. The LLT-R’s association with activities of daily living was accompanied by a small-to-medium effect size and was not better explained by demographics, global cognitive functioning, mood, or chronic medical conditions.

Conclusions

Findings provide some support for the ecological relevance of the LLT-R among older community-dwelling adults and suggest that object location learning may play a role in some everyday functioning problems that accompany typical aging.
Numt identification and removal with RtN!
Authors: Woerner August E , Cihlar Jennifer Churchill , Smart Utpal , Budowle Bruce
Published: July 2020

Motivation

Assays in mitochondrial genomics rely on accurate read mapping and variant calling. However, there are known and unknown nuclear paralogs that have fundamentally different genetic properties than that of the mitochondrial genome. Such paralogs complicate the interpretation of mitochondrial genome data and confound variant calling.

Results

Remove the Numts! (RtN!) was developed to categorize reads from massively parallel sequencing data not based on the expected properties and sequence identities of paralogous nuclear encoded mitochondrial sequences, but instead using sequence similarity to a large database of publicly available mitochondrial genomes. RtN! removes low-level sequencing noise and mitochondrial paralogs while not impacting variant calling, while competing methods were shown to remove true variants from mitochondrial mixtures.

Availability and implementation

https://github.com/Ahhgust/RtN

Supplementary information

Supplementary data are available at Bioinformatics online.
Telomere Length, Traditional Risk Factors, Factors Related to Human Immunodeficiency Virus (HIV) and Coronary Artery Disease Events in Swiss Persons Living With HIV
Authors: Engel Tanja , Raffenberg Marieke , Schoepf Isabella C , Kootstra Neeltje A , Reiss Peter , Thorball Christian W , Hasse Barbara , Hirzel Cédric , Wissel Kerstin , Roth Jan A , Bernasconi Enos , Darling Katharine E A , Calmy Alexandra , Fellay Jacques , Kouyos Roger D , Günthard Huldrych F , Ledergerber Bruno , Tarr Philip E ,   the Swiss HIV Cohort Study
Published: July 2020

Background

Leukocyte telomere length (TL) shortens with age and is associated with coronary artery disease (CAD) events in the general population. Persons living with human immunodeficiency virus (HIV; PLWH) may have accelerated atherosclerosis and shorter TL than the general population. It is unknown whether TL is associated with CAD in PLWH.

Methods

We measured TL by quantitative polymerase chain reaction (PCR) in white Swiss HIV Cohort Study participants. Cases had a first CAD event during 1 January 2000 to 31 December 2017. We matched 1–3 PLWH controls without CAD events on sex, age, and observation time. We obtained univariable and multivariable odds ratios (OR) for CAD from conditional logistic regression analyses.

Results

We included 333 cases (median age 54 years; 14% women; 83% with suppressed HIV RNA) and 745 controls. Median time (interquartile range) of TL measurement was 9.4 (5.9–13.8) years prior to CAD event. Compared to the 1st (shortest) TL quintile, participants in the 5th (longest) TL quintile had univariable and multivariable CAD event OR = 0.56 (95% confidence interval [CI], .35–.91) and OR = 0.54 (95% CI, .31–.96). Multivariable OR for current smoking was 1.93 (95% CI, 1.27–2.92), dyslipidemia OR = 1.92 (95% CI, 1.41–2.63), and for recent abacavir, cumulative lopinavir, indinavir, and darunavir exposure was OR = 1.82 (95% CI, 1.27–2.59), OR = 2.02 (95% CI, 1.34–3.04), OR = 3.42 (95% CI, 2.14–5.45), and OR = 1.66 (95% CI, 1.00–2.74), respectively. The TL-CAD association remained significant when adjusting only for Framingham risk score, when excluding TL outliers, and when adjusting for CMV-seropositivity, HCV-seropositivity, time spent with detectable HIV viremia, and injection drug use.

Conclusions

In PLWH, TL measured >9 years before, is independently associated with CAD events after adjusting for multiple traditional and HIV-related factors.
Cell-Free DNA in Pediatric Solid Organ Transplantation Using a New Detection Method of Separating Donor-Derived from Recipient Cell-Free DNA
Authors: Preka Evgenia , Ellershaw Drew , Chandler Natalie , Ahlfors Helena , Spencer Helen , Chitty Lyn S , Fenton Matthew J , Marks Stephen D
Published: July 2020

Background

The use of cell-free DNA (cfDNA) as a noninvasive biomarker to detect allograft damage is expanding rapidly. However, quantifying the low fraction of donor-derived cfDNA (ddcfDNA) is challenging and requires a highly sensitive technique. ddcfDNA detection through unique donor single nucleotide polymorphisms (SNPs) is a recent new approach, however there are limited data in pediatric solid organ transplant (SOT) recipients.

Methods

We developed an assay using a combination of 61 SNPs to quantify the ddcfDNA accurately using a custom R script to model for both the patient and donor genotypes requiring only a single sample from the allograft recipient. Performance of the assay was validated using genomic DNA (gDNA), cfDNA and donor samples where available.

Results

The R “genotype-free” method gave results comparable to when using the known donor genotype. applicable to both related and unrelated pairs and can reliably measure ddcfDNA (limit of blank, below 0.12%; limit of detection, above 0.25%; limit of quantification 0.5% resulting in 84% accuracy). 159 pediatric SOT recipients (kidney, heart, and lung) were tested without the need for donor genotyping. Serial sampling was obtained from 82 patients.

Conclusion

We have developed and validated a new assay to measure the fraction of ddcfDNA in the plasma of pediatric SOT recipients. Our method can be applicable in any donor-recipient pair without the need for donor genotyping and can provide results in 48 h at a low cost. Additional prospective studies are required to demonstrate its clinical validity in a large cohort of pediatric SOT recipients.
Potential outcomes and finite-population inference for M-estimators
Authors: Xu Ruonan
Published: July 2020

When a sample is drawn from or coincides with a finite population, the uncertainty of the coefficient estimators is often reported assuming the population is effectively infinite. The recent literature on finite-population inference instead derives an alternative asymptotic variance of the ordinary least squares estimator. Here, I extend the results to the more general setting of M-estimators and also find that the usual robust ‘sandwich’ estimator is conservative. The proposed asymptotic variance of M-estimators accounts for two sources of variation. In addition to the usual sampling-based uncertainty arising from (possibly) not observing the entire population, there is also design-based uncertainty, which is usually ignored in the common inference method, resulting from lack of knowledge of the counterfactuals. Under this alternative framework, we can obtain smaller standard errors of M-estimators when the population is treated as finite.
General anesthesia, germ cells and the missing heritability of autism: an urgent need for research
Authors: Escher Jill , Ford La Donna
Published: July 2020

Agents of general anesthesia (GA) are commonly employed in surgical, dental and diagnostic procedures to effectuate global suppression of the nervous system, but in addition to somatic targets, the subject’s germ cells—from the embryonic primordial stage to the mature gametes—may likewise be exposed. Although GA is generally considered safe for most patients, evidence has accumulated that various compounds, in particular the synthetic volatile anesthetic gases (SVAGs) such as sevoflurane, can exert neurotoxic, genotoxic and epigenotoxic effects, with adverse consequences for cellular and genomic function in both somatic and germline cells. The purpose of this paper is to review the evidence demonstrating that GA, and in particular, SVAGs, may in some circumstances adversely impact the molecular program of germ cells, resulting in brain and behavioral pathology in the progeny born of the exposed cells. Further, we exhort the medical and scientific communities to undertake comprehensive experimental and epidemiological research programs to address this critical gap in risk assessment.
Transgenerational epigenetic reprogramming of early embryos: a mechanistic model
Authors: Spadafora Corrado
Published: July 2020

The notion that epigenetic information can be transmitted across generations is supported by mounting waves of data, but the underlying mechanisms remain elusive. Here, a model is proposed which combines different lines of experimental evidence. First, it has been shown that somatic tissues exposed to stressing stimuli release circulating RNA-containing extracellular vesicles; second, epididymal spermatozoa can take up, internalize and deliver the RNA-containing extracellular vesicles to oocytes at fertilization; third, early embryos can process RNA-based information. These elements constitute the building blocks upon which the model is built. The model proposes that a continuous stream of epigenetic information flows from parental somatic tissues to the developing embryos. The flow can cross the Weismann barrier, is mediated by circulating vesicles and epididymal spermatozoa, and has the potential to generate epigenetic traits that are then stably acquired in the offspring. In a broader perspective, it emerges that a natural ‘assembly line’ operates continuously, aiming at passing the parental epigenetic blueprint in growing embryos.