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Author(s):  
Madi P. Vasquez ◽  
Rebekah J. Rylander ◽  
Jacquelyn M. Tleimat ◽  
Sarah Fritts

Numerous avian species use anthropogenic materials in constructing nests, particularly in urbanized environments. Anthropogenic materials, including plastics, have been demonstrated to have both beneficial and harmful effects on survival and reproduction. During the spring of 2018, we collected 45 Black-crested Titmouse Baeolophus atricristatus nests in San Marcos, TX, U.S. with two objectives: 1) assess and compare the mass and proportion of nest materials along an urban gradient, and 2) examine the relationship between nest materials, clutch size, and hatching success. We categorized each nest based on collection location as either urban, residential, park or rural and separated nest materials into six categories: leaves, snakeskin, twigs, moss, plastic, and non-plastic artificial materials. We then compared raw mass and proportion of mass of each nest material among urbanization categories. Nests in the urban category were 1.6-1.9 times lighter in mass than nests in other locations along the urban gradient (p = 0.01) and contained 4-5 times greater proportion, but not mass, of plastic compared to nests in all other locations. Nests in residential areas contained the greatest mass of combined anthropogenic materials. Neither clutch size nor hatching success differed based on urbanization category, nest mass, or proportions of anthropogenic or natural nest materials. The differences in mass of nests and increased proportion of plastics could have been due to a lack of natural nesting materials however, we did not estimate availability of nesting materials at any location. Results add to the growing literature that the use of anthropogenic materials in nests varies across an urban gradient, and the effect of anthropogenic materials on nesting parameters varies among species.


2022 ◽  
Vol 10 (1) ◽  
pp. 2270001
Author(s):  
Lukas Maiwald ◽  
Timo Sommer ◽  
Mikhail S. Sidorenko ◽  
Ruslan R. Yafyasov ◽  
Meraj E. Mustafa ◽  
...  

Minerals ◽  
2021 ◽  
Vol 12 (1) ◽  
pp. 41
Author(s):  
Emma Cantisani ◽  
Fabio Fratini ◽  
Elena Pecchioni

In this paper, the advances in the use of optical and electronic microscope for study of the minero-petrographic and microchemical features of lime binders of ancient mortars are discussed for various case studies. Mortars belonging to several historic periods and with different functions in building structures and archaeological sites were selected in order to verify the complementarity of optical and electronic microscope analyses applied to these artificial materials. The data obtained with the application of optical and microscope analyses were able to provide detailed and more precise information on the composition, structure, and texture of lime binders, highlighting the features of air hardening calcitic lime binder, air hardening magnesian lime binder, natural hydraulic lime binder, and air hardening binders with materials providing hydraulic characteristics added. Furthermore, a complete analysis and classification of the lime lumps was determined.


2021 ◽  
Vol 13 (24) ◽  
pp. 5139
Author(s):  
Aurélie Michel ◽  
Carlos Granero-Belinchon ◽  
Charlène Cassante ◽  
Paul Boitard ◽  
Xavier Briottet ◽  
...  

The monitoring of the Land Surface Temperature (LST) by remote sensing in urban areas is of great interest to study the Surface Urban Heat Island (SUHI) effect. Thus, it is one of the goals of the future spaceborne mission TRISHNA, which will carry a thermal radiometer onboard with four bands at a 60-m spatial resolution, acquiring daytime and nighttime. In this study, TRISHNA-like data are simulated from Airborne Hyperspectral Scanner (AHS) data over the Madrid urban area at 4-m resolution. To retrieve the LST, the Temperature and Emissivity Separation (TES) algorithm is applied with four spectral bands considering two main original approaches compared with the classical TES algorithm. First, calibration and validation datasets with a large number of artificial materials are considered (called urban-oriented database), contrary to most of the previous studies that do not use a large number of artificial material spectra during the calibration step, thus impacting the LST retrieval over these materials. This approach produces one TES algorithm with one empirical relationship, called 1MMD TES. Second, two empirical relationships are used, one for the artificial materials and the other for the natural ones. These relationships are defined thanks to two calibration datasets (artificial-surface-oriented database and natural-surface-oriented database, respectively), one containing mainly artificial materials and the other mainly natural ones. Finally, in order to use two empirical relationships, a ground cover classification map is given to the TES algorithm to separate artificial pixels from natural ones. This approach produces one material-oriented TES algorithm with two empirical relationships, called 2MMD TES. In order to perform a complete comparison of these two addenda in the TES algorithm and their impact on the LST retrieval, both AHS and TRISHNA spatial resolutions are studied, i.e., 4-m and 60-m resolutions, respectively. Relative to the calibration of the TES algorithm, we conclude that (1) the urban-oriented database is more representative of the urban areas than previous databases from the state-of-the-art, and (2) using two databases (artificial-surface-oriented and natural-surface-oriented) instead of one prevents the overestimation of the LST over natural materials and the underestimation over artificial ones. Thus, for both studied spatial resolutions (AHS and TRISHNA), we find that the 2MMD TES outperforms the 1MMD TES. This difference is especially important for artificial materials, corroborating the above conclusion. Furthermore, the comparison with ground measurements shows that, on 4-m spatial resolution images, the 2MMD TES outperforms both the 1MMD TES and the TES from the state-of-the-art used in this study. Finally, we conclude that the 2MMD TES method, with only four spectral bands, better retrieves the LST over artificial and natural materials and that the future TRISHNA sensor is suited for the monitoring of the LST over urban areas and the SUHI effect.


2021 ◽  
Vol 19 (11) ◽  
pp. 01-14
Author(s):  
Thill A. Kadhum Al-Musawi ◽  
Samira Adnan Mahdi ◽  
Sundus Yaseen Hasan AL-Asadi

Researchers have been interested in studying so-called Left-Handed Metamaterials LHM, which are artificial materials. These materials have unusual characteristics, like negative permittivity and permeability, and therefore negative index. This paper has been discussed some characteristics of LHM by designing a square split ring resonator SRR and simulating with CST microwave studio (Computer Simulation Technology) to get S-parameters. The broadband frequencies (0-30) GHz were taking to specify the effective range of frequencies to work with, which was found to be between (8- 14) GHz. Then, the parameters of SRR have been varied such as split width on, gap width, metal width, rod width and metal material. The measurements show some of parameters have been affected the values of resonance frequency and the others are not. Also, the negative values of permittivity, permeability, and refractive index have been approved.


2021 ◽  
Vol 13 (1) ◽  
Author(s):  
Shuxian Tang ◽  
Zhiyun Dong ◽  
Xiang Ke ◽  
Jun Luo ◽  
Jianshu Li

AbstractBiomineralization is the process by which organisms form mineralized tissues with hierarchical structures and excellent properties, including the bones and teeth in vertebrates. The underlying mechanisms and pathways of biomineralization provide inspiration for designing and constructing materials to repair hard tissues. In particular, the formation processes of minerals can be partly replicated by utilizing bioinspired artificial materials to mimic the functions of biomolecules or stabilize intermediate mineral phases involved in biomineralization. Here, we review recent advances in biomineralization-inspired materials developed for hard tissue repair. Biomineralization-inspired materials are categorized into different types based on their specific applications, which include bone repair, dentin remineralization, and enamel remineralization. Finally, the advantages and limitations of these materials are summarized, and several perspectives on future directions are discussed.


Author(s):  
Gang Wang ◽  
Linyun Xi ◽  
Hongbo Li ◽  
Yi Wang ◽  
Chun Wu ◽  
...  

Abstract Objective To summarize experience in the treatment of pentalogy of Cantrell (POC) in our hospital and explore the effect of artificial materials in repairing sternal defects. Materials and Methods A retrospective analysis was performed on treatment of five children with POC treated by using the Gore-Tex patch and titanium mesh in the Department of Cardio-Thoracic Surgery, Children's Hospital of Chongqing Medical University, from January 2010 to January 2019. Results The concurrent conditions included double outlet of right ventricle (n = 2), ventricular septal defect (VSD) and atrial septal defect (ASD) (n = 1), VSD and ASD and patent ductus arteriosus (n = 1), and VSD and left ventricular diverticulum (n = 1) in five cases with POC. Color Doppler echocardiography and computed tomography (CT) + three-dimensional (3D) reconstruction of the thorax and abdomen were performed preoperatively. The cardiac malformation was corrected according to color Doppler echocardiography, and a Gore-Tex patch was used to repair the pericardial defect. Titanium mesh was made according to CT 3D reconstruction with a 3D printing mold to repair sternal defects. All patients underwent a one-stage operation, all hearts were eventually repositioned, no deaths occurred after the operation, and follow-up was performed for 6 months to 2 years. The patients recovered well, and the exterior thorax was normal. Conclusion The diagnosis of POC is not difficult. The priority of surgical treatment for POC is to obtain satisfactory corrections of cardiac malformation. The repair of the pericardial defect with the Gore-Tex patch and the sternal defect with the titanium mesh can make the heart return to the mediastinum, reduce the pressure on the heart, reduce the surgical trauma, reduce the difficulty of repairing the sternal defect, and optimally restore the exterior thorax.


2021 ◽  
Author(s):  
Tarek Fawzi ◽  
Ammar A.M. Al-Talib

The development of science and applications have reached a stage where the naturally existed materials are not meeting the required properties. Metamaterials (MMs) are artificial materials that obtain their properties from their accurately engineered meta-atoms rather than the characteristics of their constituents. The size of the meta-atom is small compared to light’s wavelength. A metamaterial (MM) is a term means beyond material which has been engineered in order to possess properties that does not exist in naturally-found materials. Currently, they are made of multiple elements such as plastics and metals. They are being organized in iterating patterns at a scale that is smaller than wavelengths of the phenomena it influences. The properties of the MMs are not derived from the forming materials but their delicate size, geometry, shape, orientation, and arrangement. These properties maintain MMs to manipulate the electromagnetic waves via promoting, hindering, absorbing waves to attain an interest that goes beyond the natural materials’ potency. The apt design of MMs maintains them of influencing the electromagnetic radiation or sound in a distinctive technique never found in natural materials. The potential applications of MMs are wide, starting from medical, aerospace, sensors, solar-power management, crowd control, antennas, army equipment and reaching earthquakes shielding and seismic materials.


2021 ◽  
Author(s):  
Michael Ramage ◽  
Darshil U. Shah ◽  
Aurimas Bukauskas ◽  
Antiopi Koronaki ◽  
Anthony Colman ◽  
...  

The Centre for Natural Material Innovation in the Department of Architecture at the University of Cambridge is a cross-disciplinary centre, bringing together people and research in plant sciences, biochemistry, chemistry, fluid dynamics, engineering, and architecture. Through innovative research and experimentation, we aim to transform the way we build to achieve zero carbon emissions. Our work enables the substitution of artificial materials such as concrete and steel with nature-based materials such as timber and bamboo, and replacement of structural carbon fibre and glass fibre with hemp and flax-based biocomposites. We collaborate with other leading research institutions globally, including in the USA, China, Australia, Uruguay and others.


Author(s):  
Òscar Garibo i Orts ◽  
Alba Baeza-Bosca ◽  
Miguel A. García-March ◽  
J. Alberto Conejero

Abstract Anomalous diffusion occurs at very different scales in nature, from atomic systems to motions in cell organelles, biological tissues or ecology, and also in artificial materials, such as cement. Being able to accurately measure the anomalous exponent associated to a given particle trajectory, thus determining whether the particle subdiffuses, superdiffuses or performs normal diffusion, is of key importance to understand the diffusion process. Also it is often important to trustingly identify the model behind the trajectory, as it this gives a large amount of information on the system dynamics. Both aspects are particularly difficult when the input data are short and noisy trajectories. It is even more difficult if one cannot guarantee that the trajectories output in experiments are homogeneous, hindering the statistical methods based on ensembles of trajectories. We present a data-driven method able to infer the anomalous exponent and to identify the type of anomalous diffusion process behind single, noisy and short trajectories, with good accuracy. This model was used in our participation in the Anomalous Diffusion (AnDi) Challenge. A combination of convolutional and recurrent neural networks was used to achieve state-of-the-art results when compared to methods participating in the AnDi Challenge, ranking top 4 in both classification and diffusion exponent regression.


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