bluuebunny/crossref_metadata_2025 huggingface dataset:
Investigation of Noise Pollution in an Educational Building – Case Study of Babylon University in Iraq
Authors: Al-Isawi Rawaa , Idan Intidhar Jabir , Hassan Afrah Abood
Published: January 2022

Acoustic conditions, considered an indicator of the level of comfort, are a major concern in educational facilities since they are linked to students’ well-being and learning capacity. In this study, measurements of the acoustical comfort conditions were performed using portable IEQ meter have been assessed in four selected areas of environmental engineering department building (The classroom for fourth year, student’s corridor, teacher’s corridor and reception area) in the University of Babylon in Hillah City. This was done by analyzing the data measured for 13 months from August (2020) to August (2021). Statistical analysis by using the linear regression test was performed to determine the relationship between the selected areas. Noise is the major parameter for the educational areas that can interfere with the students’ activities and eventually, this will have a detrimental effect on the students’ physical and psychological health. The acquired results were compared to the reference values specified in the handbook to international standards for noise compliance in academic educational facilities. The results show that all the studied areas in the Environmental Engineering Department had back-ground noise levels out of the recommended threshold limit values (>50 dB) revealed that the indoor environment of these areas was of poor quality, indicating the require for interventions. This study can be considered a pilot study for future comparable research on Iraqi universities.
Car Free Zone as Planning Vision to Enhancements Transportation in City Centers (Holy Najaf City Center-Iraq)
Authors: Mohialdeen Zahraa Saeb , Ebrageem Mustafa Abduljalil
Published: January 2022

The idea of a car-free city represents a solution to the problem of fuel consumption and air pollution caused by the use of cars and replaces the idea of owning and using private cars with an efficient transportation system, and it doesn’t mean living without cars, because cars have become an integral part of a modern city. On the contrary, people can still drive in city but will not park their cars at home. Instead, they park elsewhere on their way home. Research problem: Weak regulation of the movement of vehicles in the center of the holy city of Najaf, which leads to the danger of pedestrian movement in the city center. The aim of the research: to provide a safe and effective movement for pedestrians in the center of the holy city of Najaf. Research hypothesis: The use of the car-free zone strategy in the city center transportation system achieves security for the population in the old city. The research examines reasons behind suggesting free-of-vehicle areas It gives a number of policies to achieve the strategy in the center of the holy city of Najaf, including the provision of public transportation, furniture and comfort for pedestrians in the streets, as well as easy access for the residents of the area. Thus, it is possible to draw the conclusion that there is a possibility to achieve this strategy in religious centers according to a number of policies that suit the specificity of the area.
Estimation Of Water Quality Using Geomatics Techniques for The Garraf River Basin
Authors: Daoud Al-Shuwaili Jaafar Naji , Al-Shamri Hussein Musa
Published: January 2022

This study was conducted for the purpose of estimating the soil and water quality of the Gharraf River Basin in the north of Dhi Qar Governorate using geomatics techniques represented by geographic information systems (GIS), remote sensing (RS) and positioning systems (GNSS). Which is about (90 km) from the city center. The chemical analyzes of the water samples showed that the degree of interaction was between (7.84-7.7) and the electrical conductivity (dS.m¯1.1-1.05), and the total dissolved substances were between (1106-1051ppm), and the mathematical statistical relationships were weakly correlated with the ratios of the visible space bands. pH, electrical conductivity and total dissolved materials. Calcium ratios in the study area ranged between (ppm 47.4-107) and there was a significant correlation with the range (B/R + B) with a value of (R2 = 0.51), and the results showed the ratios of magnesium in the study area between (ppm 9.67 - 26.61.) Between it and the band ratio (B/R + B)), a correlation relationship with a value of (R2=0.525), potassium recorded an average between (3.1-ppm 5.5), and there was a significant correlation between it and the band ratio (B/R +R) and it reached (R2=0.665). ), found a statistical relationship between sodium and the ratio of the band (B/R + R)) and a significant correlation was recorded with a value of (R2 = 0.527). - 102.52) And there was a correlation between the presence of chloride and the ratio of the range (B/NIR + G) as it was recorded (R2 = 0.593), the bicarbonate recorded ratios between (ppm 1.8-2.7), and there was a statistical relationship between the bicarbonate and the ratio of the range (C / R). ) amounted to (R2 = 0.573), nitrate values were recorded in the study area between (4 - 3.45 ppm) and there was a significant correlation between them and the range (B5) as it reached (R2 = 0.581), sulfate values were recorded between (207.25 - 277.5 ppm) and through Statistical analysis found that there is a correlation between The presence of sulfate with the ratio (C + B + G + R + NIR) which amounted to (R2 = 0.596), the sodium adsorption ratio (SAR) was calculated, as its values ranged between (3.192 - 0.147) and most of the statistical relationships were weakly related to the spatial ratios and were gradually The hardness values in the study area are between (99.7 - 198.1)(
Sustainable Materials Production for Oily Wastewater Treatment
Authors: Mohammed Fatima , Muhammad Al-Hamidawi Abbas Khalaf , Azeez AL-buhayder Mustafa Hasan , Mohammed Thifaf Jasim
Published: January 2022

The discharge of water from oil fields It has become one of the most significant environmental concerns associated with the oil sector. Hydrocarbon spills and crude oil fuel spills are a continual hazard to aquatic ecosystems. Inexpensive and sustainable sorbent materials are needed to mitigate the environmental damage of this pollution. To meet this need, this study features a low-density polysulfide polymer prepared by Sulfur and used cooking oils react directly. Since both sulfur and cooking oils are hydrophobic, the polymer is close to hydrocarbons such as crude oil and diesel fuel and can easily remove them from seawater. Oil can be recovered and polymer can be reused in oil spill treatment. Polysulfide is unique in that it is prepared from completely recycled waste. Sulfur is a by-product of the petroleum industry, and used cooking oil can also be used as a raw material. Therefore, waste sulfur from the petroleum industry is used to make effective anti-pollution adsorbents from the same sector According to the study’s findings, 98.55 percent of the oil was removed from the north.
A simulation process of tunable open path diode laser spectrometer to detect a carbon monoxide gas in NIR region
Authors: Mahmood Ruaa Kahtan , Mehdi Samira Adnan
Published: January 2022

By modifying the wavelength of the open path tunable diode laser spectrometer (TDLS) in the near infrared region, theoretical research was implemented to improve the detection limit of carbon monoxide gas. To adjust the correct wavelength in the NIR area, MatLab code was created. Following that, frequency domain measurements were performed in order to extract the second harmonic as an indicator of gas presence. According to the results, the correct wave length in the NIR area is (1584.877 nm), and the lowest limit of CO gas concentration is (0.012 ppb).
Mechanical Properties of Concrete Modified with Silica Fume and Integral Waterproof and Comparison with Waste Glass Aggregate Concrete
Authors: Abd-Almahdee Musa Taghreed , Abbas Hiba Ali , Jihad Ayam Jabbar
Published: January 2022

This study includes the effect of using different dosages of integral waterproof Admixture and silica fume on some mechanical properties of concrete. Concrete improved by using different ratios of integral water proof admixture(IWP admixture) to increase strength and durability, this admixture used as percentages from cement weight in each mix ranged from 0.0% to 2% ( 0.0, 1.0%, 1.2%,1.4%,1.6%,1.8%, and 2%), compressive strength test done for cubes with (10*10*10) cm for each mix. The flexural strength test was done by (10*10*40) cm beams and tested after 28 days of curing. comparison study was made between silica fume mixes properties and mixes without silica fume. Adding IWP admixture leads to increase mechanical properties of ordinary concrete, the reference mix shows compressive strength equal to 26.38 MPa, while mixes with 2% IWP gives 38.8 MPa in this study. The study also includes the effect of using 2 main dosages of silica fume to the mixes that contain IWP, the new concrete with two admixtures show better values of compressive, tensile and flexural strength comparing with mixes with only IWP, the compressive strength increased from 38.8 MPa for ordinary IWP mixes to 52.3 MPa for 10% silica fume concrete mixes, and also the flexural strength increased from 4.8 MPa for mixes with only IWP to 7.3 MPa for mixes modified with 10 % silica fume. Study include also using waste glass as fine aggregate in mixes contain IWP and 10% silica fume and that show more increment in mechanical properties also.
A Comparison Between Half and Full Fins at Nanofluids in Transformers
Authors: Ali Sajeda Abd , Hasan Ibtisam A. , Hussain Ekbal
Published: January 2022

Power transformers characterize the biggest section of capital investment within the distribution substations as well as transmission. Additionally, outages of those transformers have a substantial economic influence on the functioning of an electrical network due to the fact that the power transformers are one of the utmost overpriced constituents in an electricity structure. A suggested thermal model for a distribution transformer is investigated. The temperature distribution in the three-phase transformer (250 KVA 11/.416 KV core type, mineral oil) was obtained using “COMSOL PROGRAM” after a 3D simulation utilizing a transient analysis in light of the Finite Element Method (FEM). Meanwhile, the suggested model is being used to examine the impacts of different types of oil on HOST. To test the effect of nanoparticles on heat transfer process, the insulation oil was changed with Nanofluids and hybrid nanofluids; For present work, can be concluded when add nanofluids (Al2O3, CuO, SiC) for oil of transformer under different concentration ratio (0.3,0.5,0.8,1,1.2,1.4 % wt) and add hybrid nanofluids (oil+ Al2O3+CuO), (oil+ Al2O3+SiC), (oil+ SiC +CuO) at different concentration ratio (1,1.2,1.4 % wt). The concentration of nanofluids show a direct influence on the temperature reduction for the studied cases. Finally it can be said, the proposed model was succeeded in simulating the distribution transformer, which is in good agreement with the experimental tests adopted for this work, and it could be used as a design tool with assist of COMSOL Multiphysics Package. The present model successfully accomplished for expecting the temperature distribution at any locations in the transformer when compared with practical measurement.
Cam based Infinitely Variable Transmission Theoretic Modelling
Authors: Faleh Muhaimen , Al-Hamood Amjad , Majeed Mahir H.
Published: January 2022

Infinitely variable transmission (IVT) is a system which delivers the ratio between two turning elements to a continuous (non-discrete) variation (including zero). This article uses Solidworks software to build and simulate a cam-based IVT system. There are two identical units in the system under examination. Each unit comprises a cam with an oscillating slot connection that swings on a hinge and can be vertically shifted by changing the transmission rate. This modifier can be a power screw or a hydraulic ram. In addition, a grooved wheel and followers or an actuator are included in the system units. The raised wheels swing rotating movement, such that they are coupled by a single-way clutch to the output shaft (ratchet) to move the output shaft one way.

During the performance research, cam shapes are considered and examined inside the mechanism. a mixture of the unchanging speed and 1-5 polynomial shapes, used for the current investigation and tailored for

The results produced from the simulation generally reveal the theoretical results expected in accordance with the layout of the current IVT system. For all parts in these units, the findings imply a uniform velocity while each unit is powered. In this investigation, nevertheless, the ratchets used cause remarkable fluctuations in the angular speed of the output axis. Further research is therefore urgently needed in the choice and investigation of more efficient ratchets.
Synthesis and characterization of some 1, 5-benzodiazepine derivatives from Chalcones and their use as scavengers for some heavy metals in Environmental Systems.
Authors: Taha Ahmad Moulood , Rasheed Malath Khalaf
Published: January 2022

Chalcones (A1-A4) compounds were prepared by reacting an aldehyde (Cinnamaldehyde or terphthaldehyde) with a ketone (4-aminoacetophenone or acetylacetone) in the presence of 30% NaOH as a catalyst and ethanol as a solvent. Derivatives of 1,5-benzodiazepine (A5-A12) were prepared by reacting these prepared chalcones with orthophenylene diamine or 4-methylorthophenylene diamine in a basic medium of sodium hydroxide 10% using the microwave method. Some prepared compounds were used as scavengers of some heavy metals (iron and lead) from heavy water in ecosystems, as the results indicated the ability of these compounds to reduce or withdraw these elements from heavy water. The stability of these compounds was also tested against laser rays, as they showed resistance and stability towards laser rays.
Tsunami evacution building model (TEBM) in Teluk Palu (Palu Bay) area
Authors: Bakri M , Awalia R , Mulyati S , Zubaidi F , Rusydi M , Kasim A A , Prawita R
Published: January 2022

The research was conducted in the coastal area of Palu Bay, Lere Village. Data were collected using observation, interviews, and literature study techniques. The data were analyzed using qualitative descriptive methods and focused on the concept of the design of the tsunami evacuation building on the coast of Palu Bay. Data analysis was carried out to obtain an overview of the problems that occurred at the planning location which was analyzed with the concept of architectural design by considering the existing conditions of the site and the surrounding environment, as well as utilizing the potential of the site so that it has the potential for building functions. The conclusion obtained is based on the results of data analysis, it is necessary to have a building that can function as an evacuation container for the community when a disaster occurs in the coastal area of Palu Bay, thereby reducing the number of casualties. The benefit of this research is that it is a solution for local people to save themselves when the tsunami disaster.
Liquid-liquid extraction of Pt(IV) from hydrochloric acid solutions using PPG 425 – NaCl – H2O system
Authors: Zinov’eva I V
Published: January 2022

Today, metal extraction from e-waste is beneficial from both an environmental and economic point of view. Natural resources of metals, especially platinum group metals, are limited. At the same time, the amount of waste containing many valuable elements continues to grow. In this work, we studied the extraction of Pt (IV) from hydrochloric acid solutions using polypropylene glycol 425 (PPG 425). In the course of the experimental work, the dependence of the platinum extraction degree on the influence of hydrochloric acid concentration and medium pH in the polypropylene glycol 425 - sodium chloride - water system have been established. The maximum recovery (distribution coefficient > 3,5) has been achieved in the presence of 2 M HCl in an aqueous two-phase system (ATPS), which allows the use of the proposed system for the extraction of platinum from leaching solutions.
Implementation of the extraction method for the separation of Fe3+ and Ni2+ ions on cascade of mixing-settling extractors
Authors: Milevskii N.A. , Klychevskikh Y.A. , Solov’ev V.O. , Zinov’eva I.V. , Fedorova M.I.
Published: January 2022

Extraction processes are one of the most efficient methods of purification and separation of compounds. However, laboratory-developed methods commonly are not a complete technique that can be applied to the real manufacturing process with its extraction equipment. The extraction method for the separation of Fe3+ and Ni2+ ions using hydrochloric acid solution on a cascade of mixing-settling extractors has been determined. The extraction scheme chosen provides high efficiency of a cascade by using liquid pseudomembranes (LPM). Besides its extraction scheme simplicity, the LPM method is more economically beneficial compared to classical extraction methods. The process includes stages of Fe3+ ions extraction into the feed, followed by reextraction into the water and the feed purification for reusing it later on. The consumption of solvents and the stirring speed for the stable and efficient cascade work have been optimized. The described process is a complete technological solution for recycling processed battery waste.
Extraction of pyridine using systems based on water-soluble polymers
Authors: Solovev V O , Soloveva S V , Milevsky N A
Published: January 2022

In the process of using hydrocarbon fractions containing a large amount of nitrogenous compounds, nitrogen oxides are released into the atmospheric air, which have a negative impact on the environment and human health. The traditional cleaning method is treatment with a 25% sulfuric acid solution and subsequent hydrotreating. However, this process becomes disadvantageous due to its inability to achieve ultra-low concentrations of nitrogen-containing compounds (<10 ppm). Extraction using non-toxic and environmentally friendly water-soluble polymers is a promising alternative compared to traditional methods. This work presents the dependence of the interphase distribution of pyridine on the composition of extraction systems based on water-soluble polymers. According to the results of the study, it was found that polyethylene glycol-400, polypropylene glycol-425 and methyl ether of polyethylene glycol-350 exhibit effective extraction properties in relation to pyridine and extract it by 90.95%, 90.33% and 87.82% in one extraction stage, respectively. It was also found that the use of two-phase aqueous systems based on water-soluble polymers in the process of extracting pyridine is promising.
Study of caffeine and coumarin extraction kinetics in an aqueous two-phase system based on polyethylene glycol 1500
Authors: Zinov’eva I V
Published: January 2022

Caffeine and coumarin are organic compounds of plant origin, which have biological activity and have found wide application in medicine, pharmaceutical, perfumery and food industries. Recovery of caffeine and coumarin from aqueous solutions using liquid-liquid extraction is the most effective method. In the present work the kinetic dependences of caffeine and coumarin in the aqueous two-phase system (ATPS) of PEG 1500 - Na2SO4 - H2O were experimentally obtained. It was established that equilibrium in the system is achieved after 17 minutes for caffeine and after 12 minutes for coumarin. The effect of ultrasound on the extraction rate of caffeine and coumarin in an aqueous two-phase system was also studied.
Membranes adsorber from oil palm empty fruit branches (OPEFB): preparation and fabrication
Authors: Hidayah N , Darsono P D , Elma’ M , Mahmud  , Syauqiah I , Akbar H R , Amenia A , Putra D G L , Huda N , Rahma A
Published: January 2022

Oil Palm empty fruit branches (OPEFB) are solid waste that are numerous produced from palm oil mills. OPEFB is economically and potentially used as membrane adsorber material due to has good thermal stability, chemical resistance and biodegradability. The objectives of this work is to preparate and fabricate the OPEFB membrane adsorber which is activated by physical activation. The OPEFB has been cleaned and dried, subsequently heated at 500 °C for 30 min via pyrolysis. The activated OPEFB was sieved using 200-400 mesh and followed by the addition of 2-propanol, NH4Cl, polyvinyl alcohol (PVA) and polyethylene glycol (PEG) to become a mixture. The activated OPEFB ratio were varied in the mixtures to obtain the best composition in order to produce a good membrane adsorber texture for casting. FTIR shows on wavenumber at 1082 cm−1indicates that there is O-H stretching functional groups and bands at 943 cm−1correspons to C=O functional group. It is concluded that the membrane mixtures can be employed as membrane adsorber due to carbon content which creates strong matrix applied for gas separation.
The use of olive waste for development sustainable rigid pavement concrete material
Authors: Dahim M A , Abuaddous M , Al-Mattarneh H , Alluqmani A E , Ismail R
Published: January 2022

Recycle and reuse of agriculture and industrial wastes becomes a big chalenge in different parts of the world. The success in the waste recycle could lead to conserve the environment, reduce the use of cement, and improve health environment. This paper presents the potential use of fly ash from olive oil waste in Jordan to improve concrete material which could be used as a sustainable material for rigid pavement and building construction material. Olive oil ash was collected from olive oil mill and replace cement in producing concrete material. The range of cement replacement was 0% to 12.5% with increment 2.5%. The results indicate that olive oil reduces the workability of concrete material. The reduction of the slump of concrete increases with increasing olive ash content. Strength and durability of concrete improved and increased with increasing olive ash content in concrete up to 7.5 percent then the strength reduced. The results in this study show that the use of 7.5% was the optimum replacement of cement. This percent could produce concrete with higher strength and higher durability in comparison with the control concrete mix. Olive waste ash enhances both strength and durability because it reduces the effective water-cement ratio in concrete mix and filling the pore and void structure in concrete material. The benefits of this study could reduce the cost of concrete and recycle waste material and enhance concrete properties.
The flexural strength of glue laminated timber beams based on deflection and strain rate with four point bending loading system
Authors: Maricar S , Sulendra K , Listiawaty H , Baide H O
Published: January 2022

The development of utilization of low quality wood as construction material is needed to reduce the exploitation of natural forests. However, low quality wood species have disadvantages in terms of mechanical properties. The mechanical properties of Sengon wood are relatively low, so it does not qualify as a structural element. Therefore, the system glulam can be applied to overcome this problem. The system glulam can produce relatively light structural elements with adequate performance. This system has been extensively developed, even at the stage of applying external reinforcement, to improve the performance of structural laminated beams. On that basis, this study aims to determine the flexural strength of laminated beams of Sengon wood as a low quality wood species. In order to achieve this goal, the laminated beam was tested using method four point bending test method. Tests were carried out on long span laminated beams (L = 2750 mm) to observe flexural strength. There are five (5) laminated blocks tested, namely (BLS-1, BLS-2, BLS-3, BLS-4 and BLS-5). Each group has dimensions of 55 mm in width and 155 mm in height. Each specimen consists of six layers of wood boards with a density Falcata 0.3 g / cm3. The thickness of each layer was 26 mm and bonded with resin urea formaldehyde cold setting. Double-sided adhesive laying of 350 gr / m2 at a compressive force of 2 MPa. The analysis result shows that the load-deflection relationship between BS-L consists of linear and nonlinear phases. The load performance characteristics of the two types of laminated beams are expressed as the ratio of the proportional limit load to the maximum load. The ratio value is expressed in the form P
eBL-s = 0.7P
max BL-S andM
eBL-s = 0.7M
max BL-S. This form is similar to previous studies with a Pe to Pmax ratio of 0.80.9. In this case, the average flexural strength of the laminated beam is 17 MPa with a maximum strain of 0.004.
Shear strength behaviour of liquefiable sand of petobo on treated by agarose under direct shear test
Authors: Beddu A , Setiawan H , Nuraida  , Anugrah M R
Published: January 2022

Liquefaction process is associated with the loss of the shear strength of the saturated loose sands caused by strong earthquakes. Due to mitigitation of liquefaction hazard, an appropriate mitigation of liquefaction using environmentally friendly methods is critical and becoming increasingly important and unavoidable. The laboratory investigation was carried out to study the shear strength behaviour of liquefiable sand of Petobo treated by agarose on different concentration 1%,3% 5%. A series of direct shear test were conducted under three level of vertical stress 10 kPa, 20 kPa, and 30 kPa on the specimen. It was found that the optimum content of agarose which can be considered is at 1%-3%, using stress ratio (τ/σv) analysis shows that stress ratio decreases with increasing the vertical stress on the same agar content. The implication this result that the application of this method must consider variation of material source and characteristic, and the suitable level of vertical stresses.
Determination of earthquake prone zones at university of tadulako based on dominant periods and peak ground acceleration (PGA)
Authors: Meidji I U , Mulyati S , Janat N R , Jayadi H , Asrafil
Published: January 2022

University of Tadulako is the largest State University in Palu City. When an earthquake with a magnitude of 7.4 Mw on September 28, 2018, occurred, many buildings were damaged and even collapsed at that time, even causing casualties due to the rubble. Research on the Local Site Effect is essential for the assessment of seismic hazard. In this study, the local site effect was analyzed using the HVSR method based on microtremor data. The predominant Period (To) ranges between 1.709 s to 3.816 s, indicates that this area consists of alluvium and has a very thick sediment layer. Another parameter calculated in this paper is the peak ground acceleration (PGA) with values from 0.914 g to 0.924 g. This value is the first indicated soil damage level due to ground motions. The results of this study can be used as a consideration in the development of regional spatial planning and building structures based on earthquake analysis.
Potential of tidal power plants on Tibo Beach with spektrum method
Authors: Setiyawan  , Rusdin A , Amaliah T , Olphino
Published: January 2022

As time evolved, the demand for electrical energy also increased. As a result, renewable energy is needed to replace fossil fuels as fuel for electricity generation. Tidal water is one of the renewable alternative energy sources used as fuel for electricity generation. The tides will never run out and can also be predicted. One method that can predict data about waves is the Spectrum Method. Tide prediction data can be indicated by carrying out tidal height observations for 15 days at Tibo Beach, Donggala Regency, Central Sulawesi. Based on observations, the data obtained are the highest high water level (HHWL) is 2.4 meters, and the lowest low water level (LLWL) is 0.1 meters. Also, the type of tides on the Tibo coast is a type of mixed waves that tend to double daily, there are two tides with high water and two tides with low water with different water levels. Because the value of formzahl is 0.312. With a 2.4 meter high HHWL and a sea area of 35.4 km2, the electricity generated is 13.08 MW.
Smart water meter for automatic meter reading
Authors: Amir A , Fauzi R , Arifin Y
Published: January 2022

Clean water is one of the main sectors in smart city that need well management. One of the clean water management is utilization of water meters. The smart meter is more suitable applied for smart city. Recent Smart Water Meter allows water authorities to obtain water consumption data remotely. It also provides ability to collect and record the data in real time that can be utilised for multipurpose. However, in Indonesia, the water meters are used only to measure the total volume of clean water consumption for billing purpose only using mechanical water meter and requires labour intensive manual. Currently, many researches on smart meter design have been developed. However, the smart meter only measure and record the water consumption, without ability in which customer can determine the amount of water as needed. This paper describes design and development of smart water metering with Internet of Things. Flow meter is used as a sensor of water flowing through the pipe. The ability of the proposed smart meter is not only to measure and to record the volume water consumed, but also the customer can determine the water desired and required. The volume of water measured by the smart meter is compared with the manual measurement. The result shows that the water measured manually differs slightly from smart meter measurement using water flow sensor. The maximum difference, error, is 0.03 litres. The proposed smart meter has ability to close the main valve once the determined amount of water is reached.
Photoacoustic imaging of 3D-printed vascular networks
Authors: Ma Chenshuo , Li Wanlu , Li Daiwei , Chen Maomao , Wang Mian , Jiang Laiming , Mille Luis Santiago , Garciamendez Carlos Ezio , Zhao Zhibo , Zhou Qifa , Zhang Yu Shrike , Yao Junjie
Published: January 2022

Thrombosis in the circulation system can lead to major myocardial infarction and cardiovascular deaths. Understanding thrombosis formation is necessary for developing safe and effective treatments. In this work, using digital light processing (DLP)-based 3D printing, we fabricated sophisticated in vitro models of blood vessels with internal microchannels that can be used for thrombosis studies. In this regard, photoacoustic microscopy (PAM) offers a unique advantage for label-free visualization of the 3D-printed vessel models, with large penetration depth and functional sensitivity. We compared the imaging performances of two PAM implementations: optical-resolution PAM and acoustic-resolution PAM, and investigated 3D-printed vessel structures with different patterns of microchannels. Our results show that PAM can provide clear microchannel structures at depths up to 3.6 mm. We further quantified the blood oxygenation in the 3D-printed vascular models, showing that thrombi had lower oxygenation than the normal blood. We expect that PAM can find broad applications in 3D printing and bioprinting for in vitro studies of various vascular and other diseases.
Plastic deformation behavior and constitutive modeling of Cu-50Ta alloy during hot compression
Authors: Pu Bo , Song Ping , Li Wen-Bin , Yao Wen-Jin , Wang Xiao-Ming
Published: January 2022

This paper presents a study on plastic deformation behavior of Cu–50Ta alloy at temperatures of 286–473 K and strain-rate of 0.01–6200 s−1. The effects of temperature, strain-rate, and strain on the yield strength, flow stress, and strain-rate sensitivity coefficient were determined. A phenomenological model was established to predict variation of the strain-rate sensitivity coefficient for Cu–50Ta alloy under dynamic compression. A Johnson–Cook constitutive model was established to predict the equivalent stress–equivalent plastic strain relationship under extreme deformation (high temperature and strain-rate). The results showed that the plastic deformation behavior of Cu–50Ta alloy was affected by temperature, strain-rate, and strain. The material exhibited obvious strain-rate strengthening and thermal softening. As the strain-rate increased, the yield strength logarithmically increased. At a temperature of 286 K, the strain-rate increased from 0.01 s−1 to 6200 s−1, and the yield strength increased from 543.75 MPa to 881.13 MPa. In addition, the yield strength linearly decreased as the deformation temperature increased. Under conditions of dynamic deformation, the variation of strain-rate sensitivity coefficient could be expressed as a function of strain-rate and strain. The phenomenological model accurately described the variation of the strain-rate sensitivity coefficient of Cu–50Ta under dynamic deformation conditions. The Johnson–Cook constitutive parameters, calibrated by experimental data, described the plastic deformation behavior of the alloy under high-velocity impact.
Physical processes behind interactions of microplastic particles with natural ice
Authors: Chubarenko Irina
Published: January 2022

Microplastic particles (MPs, <5 mm) are found in marine ice in larger quantities than in seawater, however, the distribution pattern within the ice cores is not consistent. To get insights into the most general physical processes behind interactions of ice and plastic particles in cool natural environments, information from academic and applied research is integrated and verified against available field observations. Non-polar molecules of common-market plastics are hydrophobic, so MPs are weak ice nucleators, are repelled from water and ice, and concentrate within air bubbles and brine channels. A large difference in thermal properties of ice and plastics favours the concentration of MPs at the ice surface during freeze/thaw cycles. Under low environmental temperatures, falling in polar regions below the glass / brittle-ductile transition temperatures of the common-use plastics, they become brittle. This might partially explain the absence of floating macroplastics in polar waters. Freshwater freezes at a temperature well below that of its maximum density, so the water column is stably stratified, and MPs eventually concentrate at the ice surface and in air bubbles. In contrast, below growing sea ice, mechanisms of suspension freezing under conditions of (thermal plus haline) convection should permanently entangle MPs into ice. During further sea ice growth and aging, MPs are repelled from water and ice into air bubbles, brine channels, and to the upper/lower boundaries of the ice column. Sea ice permeability, especially while melting periods, can re-distribute sub-millimeter MPs through the brine channels, thus potentially introducing the variability of contamination with time. In accord with field observations, analysis reveals several competing factors that influence the distribution of MPs in sea ice. A thorough sampling of the upper ice surface, prevention of brine leakage while sampling and handling, considering the ice structure while segmenting the ice core—these steps may be advantageous for further understanding the pattern of plastic contamination in natural ice.
Biclique extension as an effective approach to identify missing links in metabolic compound–protein interaction networks
Authors: Thieme Sandra , Walther Dirk
Published: January 2022

Motivation

Metabolic networks are complex systems of chemical reactions proceeding via physical interactions between metabolites and proteins. We aimed to predict previously unknown compound–protein interactions (CPI) in metabolic networks by applying biclique extension, a network-structure-based prediction method.

Results

We developed a workflow, named BiPredict, to predict CPIs based on biclique extension and applied it to Escherichia coli and human using their respective known CPI networks as input. Depending on the chosen biclique size and using a STITCH-derived E.coli CPI network as input, a sensitivity of 39% and an associated precision of 59% was reached. For the larger human STITCH network, a sensitivity of 78% with a false-positive rate of <5% and precision of 75% was obtained. High performance was also achieved when using KEGG metabolic-reaction networks as input. Prediction performance significantly exceeded that of randomized controls and compared favorably to state-of-the-art deep-learning methods. Regarding metabolic process involvement, TCA-cycle and ribosomal processes were found enriched among predicted interactions. BiPredict can be used for network curation, may help increase the efficiency of experimental testing of CPIs, and can readily be applied to other species.

Availability and implementation

BiPredict and related datasets are available at https://github.com/SandraThieme/BiPredict.

Supplementary information

Supplementary data are available at Bioinformatics Advances online.
M&Ms: a versatile software for building microbial mock communities
Authors: García-García Natalia , Tamames Javier , Puente-Sánchez Fernando
Published: January 2022

Advances in sequencing technologies have triggered the development of many bioinformatic tools aimed to analyze 16S rDNA sequencing data. As these tools need to be tested, it is important to simulate datasets that resemble samples from different environments. Here, we introduce M&Ms, a user-friendly open-source bioinformatic tool to produce different 16S rDNA datasets from reference sequences, based on pragmatic ecological parameters. It creates sequence libraries for ‘in silico’ microbial communities with user-controlled richness, evenness, microdiversity and source environment. M&Ms allows the user to generate simple to complex read datasets based on real parameters that can be used in developing bioinformatic software or in benchmarking current tools.

Availability and implementation

The source code of M&Ms is freely available at https://github.com/ggnatalia/MMs (GPL-3.0 License).

Supplementary information

Supplementary data are available at Bioinformatics online.
The human cognition-enhancing CORD7 mutation increases active zone number and synaptic release
Authors: Paul Mila M , Dannhäuser Sven , Morris Lydia , Mrestani Achmed , Hübsch Martha , Gehring Jennifer , Hatzopoulos Georgios N , Pauli Martin , Auger Genevieve M , Bornschein Grit , Scholz Nicole , Ljaschenko Dmitrij , Müller Martin , Sauer Markus , Schmidt Hartmut , Kittel Robert J , DiAntonio Aaron , Vakonakis Ioannis , Heckmann Manfred , Langenhan Tobias
Published: January 2022

Humans carrying the CORD7 (cone-rod dystrophy 7) mutation possess increased verbal IQ and working memory. This autosomal dominant syndrome is caused by the single-amino acid R844H exchange (human numbering) located in the 310 helix of the C2A domain of RIMS1/RIM1 (Rab3-interacting molecule 1). RIM is an evolutionarily conserved multi-domain protein and essential component of presynaptic active zones, which is centrally involved in fast, Ca2+-triggered neurotransmitter release. How the CORD7 mutation affects synaptic function has remained unclear thus far.

Here, we established Drosophila melanogaster as a disease model for clarifying the effects of the CORD7 mutation on RIM function and synaptic vesicle release. To this end, using protein expression and X-ray crystallography, we solved the molecular structure of the Drosophila C2A domain at 1.92 Å resolution and by comparison to its mammalian homologue ascertained that the location of the CORD7 mutation is structurally conserved in fly RIM. Further, CRISPR/Cas9-assisted genomic engineering was employed for the generation of rim alleles encoding the R915H CORD7 exchange or R915E, R916E substitutions (fly numbering) to effect local charge reversal at the 310 helix. Through electrophysiological characterization by two-electrode voltage clamp and focal recordings we determined that the CORD7 mutation exerts a semi-dominant rather than a dominant effect on synaptic transmission resulting in faster, more efficient synaptic release and increased size of the readily releasable pool but decreased sensitivity for the fast calcium chelator BAPTA. In addition, the rim CORD7 allele increased the number of presynaptic active zones but left their nanoscopic organization unperturbed as revealed by super-resolution microscopy of the presynaptic scaffold protein Bruchpilot/ELKS/CAST.

We conclude that the CORD7 mutation leads to tighter release coupling, an increased readily releasable pool size and more release sites thereby promoting more efficient synaptic transmitter release. These results strongly suggest that similar mechanisms may underlie the CORD7 disease phenotype in patients and that enhanced synaptic transmission may contribute to their increased cognitive abilities.
Towards guided and automated programming of subthalamic area stimulation in Parkinson’s disease
Authors: Xu San San , Sinclair Nicholas C. , Bulluss Kristian J. , Perera Thushara , Lee Wee-Lih , McDermott Hugh J. , Thevathasan Wesley
Published: January 2022

Selecting the ideal contact to apply subthalamic nucleus deep brain stimulation in Parkinson’s disease can be an arduous process, with outcomes highly dependent on clinician expertise. This study aims to assess whether neuronal signals recorded intraoperatively in awake patients, and the anatomical location of contacts, can assist programming. In a cohort of 14 patients with Parkinson’s disease, implanted with subthalamic nucleus deep brain stimulation, the four contacts on each lead in the 28 hemispheres were ranked according to proximity to a nominated ideal anatomical location and power of the following neuronal signals: evoked resonant neural activity, beta oscillations and high-frequency oscillations. We assessed how these rankings predicted, on each lead: (i) the motor benefit from deep brain stimulation applied through each contact and (ii) the ‘ideal’ contact to apply deep brain stimulation. The ranking of contacts according to each factor predicted motor benefit from subthalamic nucleus deep brain stimulation, as follows: evoked resonant neural activity; r2 = 0.50, Akaike information criterion 1039.9, beta; r2 = 0.50, Akaike information criterion 1041.6, high-frequency oscillations; r2 = 0.44, Akaike information criterion 1057.2 and anatomy; r2 = 0.49, Akaike information criterion 1048.0. Combining evoked resonant neural activity, beta and high-frequency oscillations ranking data yielded the strongest predictive model (r2 = 0.61, Akaike information criterion 1021.5). The ‘ideal’ contact (yielding maximal benefit) was ranked first according to each factor in the following proportion of hemispheres; evoked resonant neural activity 18/28, beta 17/28, anatomy 16/28, high-frequency oscillations 7/28. Across hemispheres, the maximal available deep brain stimulation benefit did not differ from that yielded by contacts chosen by clinicians for chronic therapy or contacts ranked first according to evoked resonant neural activity. Evoked resonant neural activity, beta oscillations and anatomy similarly predicted how motor benefit from subthalamic nucleus deep brain stimulation varied across contacts on each lead. This could assist programming by providing a probability ranking of contacts akin to a ‘monopolar survey’. However, these factors identified the ‘ideal’ contact in only a proportion of hemispheres. More advanced signal processing and anatomical techniques may be needed for the full automation of contact selection.
Stopping versus continuing renin–angiotensin–system inhibitors after acute kidney injury and adverse clinical outcomes: an observational study from routine care data
Authors: Janse Roemer J , Fu Edouard L , Clase Catherine M , Tomlinson Laurie , Lindholm Bengt , van Diepen Merel , Dekker Friedo W , Carrero Juan-Jesus
Published: January 2022

Background

The risk–benefit ratio of continuing with renin–angiotensin system inhibitors (RASi) after an episode of acute kidney injury (AKI) is unclear. While stopping RASi may prevent recurrent AKI or hyperkalaemia, it may deprive patients of the cardiovascular benefits of using RASi.

Methods

We analysed outcomes of long-term RASi users experiencing AKI (stage 2 or 3, or clinically coded) during hospitalization in Stockholm and Sweden during 2007–18. We compared stopping RASi within 3 months after discharge with continuing RASi. The primary study outcome was the composite of all-cause mortality, myocardial infarction (MI) and stroke. Recurrent AKI was our secondary outcome and we considered hyperkalaemia as a positive control outcome. Propensity score overlap weighted Cox models were used to estimate hazard ratios (HRs), balancing 75 confounders. Weighted absolute risk differences (ARDs) were also determined.

Results

We included 10 165 individuals, of whom 4429 stopped and 5736 continued RASi, with a median follow-up of 2.3 years. The median age was 78 years; 45% were women and median kidney function before the index episode of AKI was 55 mL/min/1.73 m2. After weighting, those who stopped had an increased risk [HR, 95% confidence interval (CI)] of the composite of death, MI and stroke [1.13, 1.07–1.19; ARD 3.7, 95% CI 2.6–4.8] compared with those who continued, a similar risk of recurrent AKI (0.94, 0.84–1.05) and a decreased risk of hyperkalaemia (0.79, 0.71–0.88).

Discussion

Stopping RASi use among survivors of moderate-to-severe AKI was associated with a similar risk of recurrent AKI, but higher risk of the composite of death, MI and stroke.
The role of schools in transmission of the SARS-CoV-2 virus: quasi-experimental evidence from Germany
Authors: von Bismarck-Osten Clara , Borusyak Kirill , Schönberg Uta
Published: January 2022

This paper considers the role of school closures in the spread of the SARS-CoV-2 virus. To isolate the impact of the closures from other containment measures and identify a causal effect, we exploit variation in the start and end dates of the summer and fall school holidays across the 16 federal states in Germany using a difference-in-differences design with staggered adoption. We show that neither the summer closures nor the closures in the fall had a significant containing effect on the spread of SARS-CoV-2 among children or a spill-over effect on older generations. There is also no evidence that the return to school at full capacity after the summer holidays increased infections among children or adults. Instead, we find that the number of children infected increased during the last weeks of the summer holiday and decreased in the first weeks after schools reopened, a pattern we attribute to travel returnees.
Are we underestimating the impact of COVID-19 on children’s physical activity in Europe?—a study of 24 302 children
Authors: Kovacs Viktoria A , Brandes Mirko , Suesse Thomas , Blagus Rok , Whiting Stephen , Wickramasinghe Kremlin , Okely Anthony D
Published: January 2022

This repeat cross-sectional study investigated the impact of lockdown in Europe in Winter (January and February 2021) on children’s and adolescent’s physical activity (PA) and recreational screen time (RST), and compared PA to the lockdown in Spring 2020. An online survey was administered (n = 24 302; 6–18 years; 51.7% boys) in nine countries. PA and RST were assessed by 7-day recall. In total, 9.3% of children (95% confidence interval: 6.9–11.7) met WHO PA recommendation, which was half of the proportion observed in Spring 2020 [19.0% (18.2–19.9)]. Sixty percent exceeded the RST recommendations. This suggests that winter lockdown could have a more negative impact on PA than in spring.