bluuebunny/crossref_metadata_2025 huggingface dataset:
Managing pH of Organic Matrices and New Commercial Substrates for Ornamental Plant Production: A Methodological Approach
Authors: Cacini Sonia , Di Lonardo Sara , Orsenigo Simone , Massa Daniele
Published: April 2021

Professional peat-free substrates for ornamental plant production are increasingly required by nursery growers. Most promising materials are green compost, coconut coir dust, and woody fibre, used alone or in mixtures. One of the major concerns is pH, usually higher than optimal. In this work, a method based on a three-step procedure was adopted to acidify three organic matrices alone or in mixtures and to individuate the most suitable product, between iron(II) sulphate 7-hydrate and elemental sulphur chips. Firstly, the determination of the buffering capacity by dilution with sulphuric acid was carried out to determine dosages. Afterwards, an incubation trial of 84 (iron(II) sulphate) or 120 days (sulphur chips) was conducted on matrices and substrate mixtures with calculated doses in a climatic chamber maintained at 21 °C. Iron(II) sulphate resulted not suitable because it caused a rapid, but not lasting, pH lowering and an excessive electrical conductivity (EC) increase. Sulphur chips could instead guarantee an adequate and lasting pH lowering. These results were then validated in the open field trial on matrices and substrates. The proposed acidification methodology could be considered in developing new substrates, but the rapidity of pH acidification and EC increase on plant and mineral nutrition should be further investigated.
Phenotypic and Molecular Characterization of Brazilian Capsicum Germplasm
Authors: Brilhante Bruna Dias Gomes , Santos Talles de Oliveira , Santos Pedro Henrique Araújo Diniz , Kamphorst Samuel Henrique , Neto José Dias Souza , Rangel Leandro Heitor , Valadares Fernanda Vargas , de Almeida Rafael Nunes , Rodrigues Rosana , Júnior Alexandre Cristiano Santos , Moulin Monique Moreira
Published: April 2021

Population growth and the high demand for food production has caused environmental degradation losses in biodiversity. The conservation of genetic resources is the most appropriate strategy for maintaining the variability of species of great importance, such as Capsicum. In this study, we describe the characterization of 69 pepper accessions of four Capsicum species from different regions of Brazil on the basis of qualitative and quantitative descriptors and ISSR markers. The 11 quantitative descriptors grouped the 69 populations into five clades. The fruit traits had the greater discrimination power. A strong correlation was detected between some pairs of quantitative descriptors: petiole and fruit length, fruit diameter and fresh fruit mass, leaf length and leaf width, canopy and plant height, stem diameter and plant height, stem diameter and canopy diameter. A negative correlation was also observed between plant height and pericarp thickness. Moreover, the molecular analysis grouped accessions into five clades. The morpho-agronomic and molecular characterization were efficient to estimate the genetic diversity between accessions, being important tools for the knowledge and use of accessions. This study is of great importance to preserve pepper germplasm and to provide data to facilitate the process of the selection in breeding programs.
The Effect of Subsurface Placement of Mineral Fertilizer on Some Soil Properties under Reduced Tillage Soybean Cultivation
Authors: Kraska Piotr , Andruszczak Sylwia , Gierasimiuk Paweł , Rusecki Hubert
Published: April 2021

One of the adverse effects of no-tillage is the accumulation of nutrients (in particular P and K) in the top soil layer. The subsurface application of mineral fertilizers at a depth of 10–30 cm can reduce this phenomenon and at the same time provide a relatively uniform access to soil nutrients for plant roots. Such a method of mineral fertilizer application can additionally decrease the environmental risk associated with water eutrophication because the water runoff from fields, where the soil P content is high, is reduced. The aim of this research was to evaluate the effect of the subsurface application of different rates of a compound mineral fertilizer on the content of some macronutrients, soil organic carbon content (SOC), and soil pH in a field after the harvest of soybean grown under reduced tillage conditions. The field experiment was conducted during the growing seasons of 2014/2015–2016/2017 in the village of Rogów, Zamość County, Poland. It was set up as a split-plot design in four replicates. The first experimental factor included two methods of mineral fertilization application: fertilizer broadcast over the soil surface (S); fertilizer applied deep (subsurface placed) using a specially designed cultivator (Sub-S). The other factor was the rates of the mineral fertilizer (NPKS): 85 kg∙ha−1 (F85) and 170 kg∙ha−1 (F170). Over the successive years of the study, the SOC content was found to increase. However, neither the fertilization rate nor the method of fertilizer application caused any significant difference in organic carbon. Under subsurface fertilizer application conditions, a higher soil pH was found in treatment F85, however, when the fertilizer was surface-applied, the soil in treatment F170 had a higher pH value. During the three-year study period, the P and K content in the 0–30 cm soil layer was higher than in the 30–60 cm and 60–90 cm layers. In turn, the highest Mg content was determined in the 30–60 cm layer. In the case of both mineral fertilizer application methods, a higher P content was determined in the soil fertilized at a rate of 170 kg NPKS, compared with a rate of 85 kg∙ha−1. The surface application of the higher rate of mineral fertilization resulted in an increase in the soil K content. On the other hand, when the mineral fertilizer was subsurface-applied, a higher soil K was determined in the treatments with lower mineral fertilization.
Maximizing Land Use Efficiency and Productivity of Soybean and Fodder Maize Intercrops through Manipulating Sowing Schedule and Maize Harvest Regime
Authors: Salama Heba S. A. , Abdel-Moneim Mahmoud H.
Published: April 2021

The incorporation of both food and forage crops in an intercropping system is receiving increasing attention, especially in developing countries with increasing populations and limited resources. In a two-year (2019–2020) field trial, conducted in Northern Egypt, productivity of soybean and fodder maize, as well as the quality of maize herbage, were investigated under three sowing schedules; soybean and maize sown together, and maize sown 15 and 30 days after soybean, in addition to soybean and fodder maize sown in pure stands, with maize harvested at green fodder maturity (GFM), and silage maturity (SM). Harvesting fodder maize at SM resulted in higher herbage yield than harvesting it at GFM, yet it negatively affected the soybean productivity. However, this negative impact was offset when fodder maize sowing was delayed 30 days after soybean sowing. Maize harvested at GFM was characterized by a higher leaf component, which was reflected in its higher crude protein content, yet the decline in quality with advanced maturity was to a great extent, counterbalanced by the presence of high-quality ears in maize harvested at SM. This was clear in its lower fiber and higher non-fiber carbohydrate contents. Land equivalent ratio (LER) demonstrated yield advantage with the delayed sowing of fodder maize (LER > 1), while the dry matter equivalent ratio (DMER) associated the yield advantage with the late harvesting of fodder maize at SM (DMER > 1), across all sowing schedules, which was more realistic for an additive intercropping model where the dry matter is the economic component. In a soybean-fodder maize intercropping system, whether fodder maize will be cultivated for green feeding or for silage production, it is recommended that sowing is delayed until 30 days after the soybean, in order to maximize yield advantage and land use efficiency.
Investigating the Impact of Root-Lesion Nematodes (Pratylenchus thornei) and Crown Rot (Fusarium pseudograminearum) on Diverse Cereal Cultivars in a Conservation Farming System
Authors: Thompson John P. , Clewett Timothy G.
Published: April 2021

In two experiments on a farm practicing conservation agriculture, the grain yield of a range of wheat cultivars was significantly (p < 0.001) negatively related to the post-harvest population densities of Pratylenchus thornei in the soil profile to 45 cm depth. In a third and fourth experiment with different rotations, methyl bromide fumigation significantly (p < 0.05) decreased (a) a low initial population density of P. thornei in the soil profile to 90 cm depth and (b) a high initial population of P. thornei to 45 cm depth, and a medium level of the crown rot fungus, Fusarium pseudograminearum, at 0–15 cm depth to a low level. For a range of wheat and durum cultivars, grain yield and response to fumigation were highly significantly (p < 0.001) related to (a) the P. thornei tolerance index of the cultivars in the third experiment, and (b) to both the P. thornei tolerance index and the crown rot resistance index in the fourth experiment. In the latter, grain yield was significantly (p < 0.001) positively related to biomass at anthesis and negatively related to percentage whiteheads at grain fill growth stage. One barley cultivar was more tolerant to both diseases than the wheat and durum cultivars. Crop rotation, utilizing crop cultivars resistant and tolerant to both P. thornei and F. pseudograminearum, is key to success for conservation farming in this region.
Prepartum and Postpartum Feed Restrictions Affect Blood Metabolites and Hormones Reducing Colostrum and Milk Yields in Fat-Tailed Dairy Sheep
Authors: Zarrin Mousa , Sanginabadi Meysam , Nouri Mahrokh , Ahmadpour Amir , Hernández-Castellano Lorenzo E.
Published: April 2021

This study aimed to investigate the effect of prepartum and postpartum feed restriction on body weight (BW), blood metabolites, and hormones as well as colostrum and milk yields and compositions in fat-tailed dairy sheep. In this study, 20 multiparous and pregnant ewes were randomly allocated to either the control (Ctrl; n = 10) or the feed-restricted (FR; n = 10) groups from week −5 to week 5 relative to parturition. Despite dry matter intake being decreased in the FR group compared to the Ctrl throughout both prepartum and postpartum periods, no differences in BW were detected between groups in any of the studied periods. Feed restriction increased both free fatty acids and beta-hydroxybutyrate concentrations during both prepartum and postpartum periods. Similarly, feed restriction increased triglyceride concentration postpartum. Additionally, feed restriction increased insulin and growth hormone and decreased prolactin concentrations during both prepartum and postpartum periods. Feed restriction caused a decreased colostrum yield and a relative increase of the main colostrum components in the FR group. Similarly, milk yield decreased in the FR group compared to the Ctrl group, although milk components were not affected. In conclusion, feed restriction did not affect BW but decreased colostrum and milk yield in fat-tailed dairy sheep.
Employee Management and Animal Care: A Comparative Ethnography of Two Large-Scale Dairy Farms in China
Authors: Chen Maria , von Keyserlingk Marina A. G. , Magliocco Sabina , Weary Daniel M.
Published: April 2021

Farm management can directly and indirectly affect animal care. We explored how farm management affected animal care on two large dairy farms in China (anonymized as Farm A and Farm B). We used a mini-ethnographic case study design whereby the first author lived for 38 days on Farm A and 23 days on Farm B. She conducted participant observation and ethnographic interviews with farm staff positions within five departments in Farm A and six departments in Farm B. In addition, she conducted 13 semi-structured interviews (seven on Farm A; six on Farm B). We used template analysis to generate key themes. On both farms, workers believed that animal care practices had improved over time, due to three key employee management factors: 1) organizational culture, 2) competency of worker and management, and 3) an effective incentive system. Our results suggest that animal care may be improved in this context by: 1) promoting a culture in which workers have ‘grit’ and are eager to learn, 2) ensuring basic worker wellbeing, and 3) using animal care outcomes as performance indicators linked to pay.
Identifying Habitat Elements from Bird Images Using Deep Convolutional Neural Networks
Authors: Wang Zhaojun , Wang Jiangning , Lin Congtian , Han Yan , Wang Zhaosheng , Ji Liqiang
Published: April 2021

With the rapid development of digital technology, bird images have become an important part of ornithology research data. However, due to the rapid growth of bird image data, it has become a major challenge to effectively process such a large amount of data. In recent years, deep convolutional neural networks (DCNNs) have shown great potential and effectiveness in a variety of tasks regarding the automatic processing of bird images. However, no research has been conducted on the recognition of habitat elements in bird images, which is of great help when extracting habitat information from bird images. Here, we demonstrate the recognition of habitat elements using four DCNN models trained end-to-end directly based on images. To carry out this research, an image database called Habitat Elements of Bird Images (HEOBs-10) and composed of 10 categories of habitat elements was built, making future benchmarks and evaluations possible. Experiments showed that good results can be obtained by all the tested models. ResNet-152-based models yielded the best test accuracy rate (95.52%); the AlexNet-based model yielded the lowest test accuracy rate (89.48%). We conclude that DCNNs could be efficient and useful for automatically identifying habitat elements from bird images, and we believe that the practical application of this technology will be helpful for studying the relationships between birds and habitat elements.
Dose-Dependent Impact of Bee Pollen Supplementation on Macroscopic and Microscopic Structure of Femoral Bone in Rats
Authors: Martiniakova Monika , Bobonova Ivana , Toman Robert , Galik Branislav , Bauerova Maria , Omelka Radoslav
Published: April 2021

Bee pollen has been successfully used as a feed additive with beneficial impacts on productive, reproductive, and immune conditions of animals. However, its effect on bone structure and bone health remains controversial. Therefore, the purpose of our study was to examine the impact of bee pollen supplementation on macroscopic and microscopic structure of a femoral bone using rats as suitable animal models. Male rats (1 month-old) were assigned into three groups: control (C group) that was fed a standard diet without bee pollen and two bee pollen supplemented groups (P1 and P2 groups) that received an experimental diet including 0.5% and 0.75% of bee pollen, respectively, for 3 months. A number of unfavorable effects of 0.75% bee pollen administration on bone weight, cortical bone thickness, calcium content, alkaline phosphatase activity, sizes of primary osteons’ vascular canals, Haversian canals and secondary osteons in the cortical bone have been recorded, whereas these bone parameters were significantly decreased in the P2 group versus the C group. On the contrary, the concentration of 0.5% did not affect any of bone features mentioned above. In conclusion, the impact of bee pollen supplementation on femoral bone structure of rats depends on the dose used.
Pan and Core Genome Analysis of 183 Mycobacterium tuberculosis Strains Revealed a High Inter-Species Diversity among the Human Adapted Strains
Authors: Zakham Fathiah , Sironen Tarja , Vapalahti Olli , Kant Ravi
Published: April 2021

Tuberculosis (TB) is an airborne communicable disease with high morbidity and mortality rates, especially in developing countries. The causal agents of TB belong to the complex Mycobacterium tuberculosis (MTBc), which is composed of different human and animal TB associated species. Some animal associated species have zoonotic potential and add to the burden of TB management. The BCG (“Bacillus Calmette-Guérin”) vaccine is widely used for the prevention against TB, but its use is limited in immunocompromised patients and animals due to the adverse effects and disseminated life-threatening complications. In this study, we aimed to carry out a comparative genome analysis between the human adapted species including BCG vaccine strains to identify and pinpoint the conserved genes related to the virulence across all the species, which could add a new value for vaccine development. For this purpose, the sequences of 183 Mycobacterium tuberculosis (MTB) strains were retrieved from the freely available WGS dataset at NCBI. The species included: 168 sensu stricto MTB species with other human MTB complex associated strains: M. tuberculosis var. africanum (3), M. tuberculosis var. bovis (2 draft genomes) and 10 BCG species, which enabled the analysis of core genome which contains the conserved genes and some virulence factor determinants. Further, a phylogenetic tree was constructed including the genomes of human (183); animals MTB adapted strains (6) and the environmental Mycobacterium strain “M. canettii”. Our results showed that the core genome consists of 1166 conserved genes among these species, which represents a small portion of the pangenome (7036 genes). The remaining genes in the pangenome (5870) are accessory genes, adding a high inter-species diversity. Further, the core genome includes several virulence-associated genes and this could explain the rare infectiousness potential of some attenuated vaccine strains in some patients. This study reveals that low number of conserved genes in human adapted MTBc species and high inter-species diversity of the pan-genome could be considered for vaccine candidate development.
Proteomic Charting of Imipenem Adaptive Responses in a Highly Carbapenem Resistant Clinical Enterobacter roggenkampii Isolate
Authors: Nepal Suruchi , Maaß Sandra , Grasso Stefano , Cavallo Francis M. , Bartel Jürgen , Becher Dörte , Bathoorn Erik , van Dijl Jan Maarten
Published: April 2021

Gram-negative bacteria belonging to the Enterobacter cloacae complex are increasingly implicated in difficult-to-treat nosocomial infections, as exemplified by a recently characterized highly carbapenem-resistant clinical Enterobacter roggenkampii isolate with sequence type (ST) 232. While mechanisms of carbapenem resistance are well-understood, little is known about the responses of highly drug-resistant bacteria to these antibiotics. Our present study was therefore aimed at charting the responses of the E. roggenkampii ST232 isolate to the carbapenem imipenem, using a ‘stable isotope labeling of amino acids in cell culture’ approach for quantitative mass spectrometry. This unveiled diverse responses of E. roggenkampii ST232 to imipenem, especially altered levels of proteins for cell wall biogenesis, central carbon metabolism, respiration, iron–sulfur cluster synthesis, and metal homeostasis. These observations suggest a scenario where imipenem-challenged bacteria reduce metabolic activity to save resources otherwise used for cell wall biogenesis, and to limit formation of detrimental reactive oxygen species at the cytoplasmic membrane due to respiration and Fenton chemistry. We consider these observations important, because knowing the adaptive responses of a highly resistant bacterium of the E. cloacae complex to last-resort antibiotics, such as imipenem, provides a ‘sneak preview’ into the future development of antibiotic resistance in this emerging group of pathogens.
Exploring Mycosporine-Like Amino Acids (MAAs) as Safe and Natural Protective Agents against UV-Induced Skin Damage
Authors: Singh Anjali , Čížková Mária , Bišová Kateřina , Vítová Milada
Published: April 2021

Prolonged exposure to harmful ultraviolet radiation (UVR) can induce many chronic or acute skin disorders in humans. To protect themselves, many people have started to apply cosmetic products containing UV-screening chemicals alone or together with physical sunblocks, mainly based on titanium–dioxide (TiO2) or zinc-oxide (ZnO2). However, it has now been shown that the use of chemical and physical sunblocks is not safe for long-term application, so searches for the novel, natural UV-screening compounds derived from plants or bacteria are gaining attention. Certain photosynthetic organisms such as algae and cyanobacteria have evolved to cope with exposure to UVR by producing mycosporine-like amino acids (MAAs). These are promising substitutes for chemical sunscreens containing commercially available sunblock filters. The use of biopolymers such as chitosan for joining MAAs together or with MAA-Np (nanoparticles) conjugates will provide stability to MAAs similar to the mixing of chemical and physical sunscreens. This review critically describes UV-induced skin damage, problems associated with the use of chemical and physical sunscreens, cyanobacteria as a source of MAAs, the abundance of MAAs and their biotechnological applications. We also narrate the effectiveness and application of MAAs and MAA conjugates on skin cell lines.
Isoprene: An Antioxidant Itself or a Molecule with Multiple Regulatory Functions in Plants?
Authors: Pollastri Susanna , Baccelli Ivan , Loreto Francesco
Published: April 2021

Isoprene (C5H8) is a small lipophilic, volatile organic compound (VOC), synthesized in chloroplasts of plants through the photosynthesis-dependent 2-C-methyl-D-erythritol 4-phosphate (MEP) pathway. Isoprene-emitting plants are better protected against thermal and oxidative stresses but only about 20% of the terrestrial plants are able to synthesize isoprene. Many studies have been performed to understand the still elusive isoprene protective mechanism. Isoprene reacts with, and quenches, many harmful reactive oxygen species (ROS) like singlet oxygen (1O2). A role for isoprene as antioxidant, made possible by its reduced state and conjugated double bonds, has been often suggested, and sometimes demonstrated. However, as isoprene is present at very low concentrations compared to other molecules, its antioxidant role is still controversial. Here we review updated evidences on the function(s) of isoprene, and outline contrasting indications on whether isoprene is an antioxidant directly scavenging ROS, or a membrane strengthener, or a modulator of genomic, proteomic and metabolomic profiles (perhaps as a secondary effect of ROS removal) eventually leading to priming of antioxidant plant defenses, or a signal of stress for neighbor plants alike other VOCs, or a hormone-like molecule, controlling the metabolic flux of other hormones made by the MEP pathway, or acting itself as a growth and development hormone.
Nanotechnology-Based Drug Delivery to Improve the Therapeutic Benefits of NRF2 Modulators in Cancer Therapy
Authors: Sezgin-Bayindir Zerrin , Losada-Barreiro Sonia , Bravo-Díaz Carlos , Sova Matej , Kristl Julijana , Saso Luciano
Published: April 2021

The disadvantages of conventional anticancer drugs, such as their low bioavailability, poor targeting efficacy, and serious side effects, have led to the discovery of new therapeutic agents and potential drug delivery systems. In particular, the introduction of nano-sized drug delivery systems (NDDSs) has opened new horizons for effective cancer treatment. These are considered potential systems that provide deep tissue penetration and specific drug targeting. On the other hand, nuclear factor erythroid 2-related factor 2 (NRF2)-based anticancer treatment approaches have attracted tremendous attention and produced encouraging results. However, the lack of effective formulation strategies is one of the factors that hinder the clinical application of NRF2 modulators. In this review, we initially focus on the critical role of NRF2 in cancer cells and NRF2-based anticancer treatment. Subsequently, we review the preparation and characterization of NDDSs encapsulating NRF2 modulators and discuss their potential for cancer therapy.
Supplementary Light Differently Influences Physico-Chemical Parameters and Antioxidant Compounds of Tomato Fruits Hybrids
Authors: Palmitessa Onofrio Davide , Durante Miriana , Caretto Sofia , Milano Francesco , D'Imperio Massimiliano , Serio Francesco , Santamaria Pietro
Published: April 2021

One of the challenges for agriculture in the coming years will be producing more food avoiding reducing the nutritional values of fruits and vegetables, sources of nutraceutical compounds. It has been demonstrated that light-emitting diodes (LEDs) used as a supplementary light (SL) technology improve tomato yield in Mediterranean greenhouses, but few data have been reported about SL effects on fruit physio-chemical parameters. In this study, three tomato hybrid (F1) cultivars were grown for year-round production in a commercial semi-closed glasshouse in Southern Italy: red cherry type (“Sorentyno”), red plum type (“Solarino”), and yellow plum type (“Maggino”). From 120 to 243 days after transplant (DAT), Red/White/Blue LEDs were used as SL. The fruits harvested 180 DAT were analyzed and those obtained under LEDs had 3% more dry weight, 15% more total soluble solids, and 16% higher titratable acidity than fruits grown only under natural light. Generally, the antioxidant activity and the mineral profile of the fruits were not negatively influenced by SL. Lycopene content was unchanged and vitamin C content of “Sorentyno” even increased by 15% under LEDs. Overall, LEDs used as SL technology could be one of the tools used by agriculture in Mediterranean basin to produce more food maintaining high quality production.
Mitochondrial Transplantation Modulates Inflammation and Apoptosis, Alleviating Tendinopathy Both In Vivo and In Vitro
Authors: Lee Ji Min , Hwang Jung Wook , Kim Mi Jin , Jung Sang Youn , Kim Kyung-Soo , Ahn Eun Hee , Min Kyunghoon , Choi Yong-Soo
Published: April 2021

Tendinopathy is a common musculoskeletal condition causing pain and dysfunction. Conventional treatment and surgical procedures for tendinopathy are insufficient; accordingly, recent research has focused on tendon-healing regenerative approaches. Tendon injuries usually occur in the hypoxic critical zone, characterized by increased oxidative stress and mitochondrial dysfunction; thus, exogenous intact mitochondria may be therapeutic. We aimed to assess whether mitochondrial transplantation could induce anti-inflammatory activity and modulate the metabolic state of a tendinopathy model. Exogenous mitochondria were successfully delivered into damaged tenocytes by centrifugation. Levels of Tenomodulin and Collagen I in damaged tenocytes were restored with reductions in nuclear factor-κB and matrix metalloproteinase 1. The dysregulation of oxidative stress and mitochondrial membrane potential was attenuated by mitochondrial transplantation. Activated mitochondrial fission markers, such as fission 1 and dynamin-related protein 1, were dose-dependently downregulated. Apoptosis signaling pathway proteins were restored to the pre-damage levels. Similar changes were observed in a collagenase injection-induced rat model of tendinopathy. Exogenous mitochondria incorporated into the Achilles tendon reduced inflammatory and fission marker levels. Notably, collagen production was restored. Our results demonstrate the therapeutic effects of direct mitochondrial transplantation in tendinopathy. These effects may be explained by alterations in anti-inflammatory and apoptotic processes via changes in mitochondrial dynamics.
Complex Wavefront Shaping through a Multi-Core Fiber
Authors: Sun Jiawei , Koukourakis Nektarios , Czarske Jürgen W.
Published: April 2021

Wavefront shaping through a multi-core fiber (MCF) is turning into an attractive method for endoscopic imaging and optical cell-manipulation on a chip. However, the discrete distribution and the low number of cores induce pixelated phase modulation, becoming an obstacle for delivering complex light field distributions through MCFs. We demonstrate a novel phase retrieval algorithm named Core–Gerchberg–Saxton (Core-GS) employing the captured core distribution map to retrieve tailored modulation hologram for the targeted intensity distribution at the distal far-field. Complex light fields are reconstructed through MCFs with high fidelity up to 96.2%. Closed-loop control with experimental feedback denotes the capability of the Core-GS algorithm for precise intensity manipulation of the reconstructed light field. Core-GS provides a robust way for wavefront shaping through MCFs; it facilitates the MCF becoming a vital waveguide in endoscopic and lab-on-a-chip applications.
Material Removal Model for Lapping Process Based on Spiral Groove Density
Authors: Lee Taekyung , Jeong Haedo , Lee Sangjik , Cho Hanchul , Kim Doyeon , Kim Hyoungjae
Published: April 2021

The increasing demand for single-crystal wafers combined with the increase in diameter of semiconductor wafers has warranted further improvements in thickness variation and material removal rate during lapping to ensure price competitiveness of wafers; consequently, the lapping process has gained the attention of researchers. However, there is insufficient research on the effect of platen grooves on the lapping process. In this study, the parameters to describe grooves were defined in order to understand their influence on the lapping process, and a material removal model was suggested based on indentation theory and subsequently experimentally validated. The results indicate that changes in groove density affect the lubrication condition at the contact interface as well as the probability of abrasive participation by varying the oil film thickness. When fabricating the groove for a lapping platen, a groove density at the critical groove density (CGD) or higher should be selected. The higher the groove density, the easier it is to avoid the CGD, and the higher is the material removal rate. The results of this study will enable engineers to design lapping platen grooves that are suitable for the production of modern semiconductor wafers.
EM-Driven Multi-Objective Optimization of a Generic Monopole Antenna by Means of a Nested Trust-Region Algorithm
Authors: Bekasiewicz Adrian , Koziel Slawomir , Plotka Piotr , Zwolski Krzysztof
Published: April 2021

Antenna structures for modern applications are characterized by complex and unintuitive topologies that are difficult to develop when conventional, experience-driven techniques are of use. In this work, a method for the automatic generation of antenna geometries in a multi-objective setup has been proposed. The approach involves optimization of a generic spline-based radiator with an adjustable number of parameters using a nested, trust region-based algorithm. The latter iteratively increases the dimensionality of the radiator in order to gradually improve its performance. The method has been used to generate a set of nine antenna designs, representing a trade-off between minimization of reflection within 3.1 GHz to 10.6 GHz and a reduction of size. The properties of the optimized designs vary along the Pareto set from −10 dB to −20 dB and from 230 mm2 to 757 mm2 for the first and second objectives, respectively. The presented design approach has been validated against a genuine, population-based optimization routine. Furthermore, the smallest Pareto-optimal design has been compared to the antennas from the literature.
Antioxidant Production in Dunaliella
Authors: Roy Uttam Kumer , Nielsen Birthe Vejby , Milledge John James
Published: April 2021

Microalgae have become an attractive natural source of a diverse range of biomolecules, including enzymatic and non-enzymatic antioxidants; nevertheless, economically sustainable production of such compounds from microalgae biomass is still challenging. The main hurdles are: (a) increasing microalgae yield; (b) achieving optimal cultivation conditions; (c) energy-efficient and cost-effective downstream processing (extraction and purification); (d) optimal storage of post-processed antioxidant molecules. This review provides a detailed overview of enzymatic and non-enzymatic antioxidants in the cellular metabolism of the commercially important microalgae Dunaliella, industrial applications of antioxidant enzymes, strategies to enhanced antioxidant accumulation in cells, and the opportunities and limitations of current technologies for antioxidant enzymes production from microalgae biomass as an alternative to common microbial sources.
Multi-Scale Convolutional Recurrent Neural Network for Bearing Fault Detection in Noisy Manufacturing Environments
Authors: Oh Seokju , Han Seugmin , Jeong Jongpil
Published: April 2021

The failure of a facility to produce a product can have significant impacts on the quality of the product. Most equipment failures occur in rotating equipment, with bearing damage being the biggest cause of failure in rotating equipment. In this paper, we propose a denoising autoencoder (DAE) and multi-scale convolution recurrent neural network (MS-CRNN), wherein the DAE accurately inspects bearing defects in the same environment as bearing vibration signals in the field, and the MS-CRNN inspects and classifies defects. We experimented with adding random noise to create a dataset that resembled noisy manufacturing installations in the field. From the results of the experiment, the accuracy of the proposed method was more than 90%, proving that it is an algorithm that can be applied in the field.
The Rate of Correctly Planned Size of Digital Templating in Two Planes—A Comparative Study of a Short-Stem Total Hip Implant with Primary Metaphyseal Fixation and a Conventional Stem
Authors: Buschatzky Johanna K. , Schwarze Michael , Wirries Nils , von Lewinski Gabriela , Windhagen Henning , Floerkemeier Thilo , Budde Stefan
Published: April 2021

(1) Background: Preoperative templating is mainly conducted on an anteroposterior pelvic overview X-ray. For short stem hip arthroplasty, the choice of the optimal size is especially crucial to avoid complications. Thus, the study aimed to determine if there is an increased rate of correctly planned sizes using two radiological planes. (2) Methods: 50 patients with a conventional stem and 100 with a short stem total hip arthroplasty were analyzed. Without knowing the implanted size, three independent orthopedic surgeons performed digital templating: once using the anteroposterior pelvic overview only and once using the lateral view in addition. (3) Results: The rate of correctly planned sizes (+/−1 size compared to the inserted size) of templating with one plane was 86.3% ± 9.5% in short stem hip arthroplasty and 88.4% ± 6.0% in conventional stem arthroplasty. By adding the lateral view, the rate of correctly planned sizes was 89.9% ± 12.0% for the short stem hip arthroplasty group and 89.4% ± 9.8% for the conventional group (p > 0.1). (4) A potential positive effect of preoperative templating using an additional lateral X-ray view for short stem implants may be suggested based on the results of this study, which did, however, not reach statistical significance.
Experimental Study on Slender CFRP-Confined Circular RC Columns under Axial Compression
Authors: Hu Zhongjun , Li Quanheng , Yan Hongfeng , Wen Yuchuan
Published: April 2021

The test results on the performance of carbon fiber-reinforced polymer (CFRP)-confined reinforced concrete (RC) columns under axial compression load are presented in this study. Twelve slender CFRP-confined circular RC columns with a diameter of 200 mm were divided into two groups. Six specimens with different slenderness ratios of 12, 20, 32, 40, 48, and 56 were contained in each group. The experimental results demonstrated the circumferential CFRP wrap was effective in enhancing the ultimate axial load of slender CFRP-confined circular RC columns compared with unwrapped RC columns. The experimental investigation also showed that the slenderness of the specimens had important influences on the axial compressive behavior, and the axial bearing capacity of slender CFRP-confined circular RC columns decreased as the slenderness ratio increased. In order to predict the load-carrying capacities of slender CFRP-confined circular RC columns, a formula was proposed and the prediction agreed with the experiments. The slenderness of slender CFRP-confined circular RC columns was recommended to be less than 26.5 in practical engineering.
Bond Strength Stability of Different Dual-Curing Adhesive Cements towards CAD-CAM Resin Nanoceramic: An In Vitro Study
Authors: Vergano Edoardo Alberto , Baldi Andrea , Comba Allegra , Italia Edoardo , Ferrero Giorgio , Femiano Rossella , Femiano Felice , Scotti Nicola
Published: April 2021

Background: To evaluate different adhesive luting procedures on coronal dentin bond-strength of Cerasmart CAD-CAM blocks with μTBS test. Methods: 36 molar crowns were flattened in order to expose sound dentin and a standardized smear layer was created with 600 grit paper. Specimens were divided into six groups according to the luting cement employed (n = 12 each): G1: Panavia V5 (Kuraray, Japan); G2: Bifix QM (Voco, Germany); G3: Estecem (Tokuyama, Japan). CAD-CAM blocks (Cerasmart, GC), shade A2LT, size 14, were sectioned with a diamond saw to obtain 4 mm high specimens, which were then luted on the coronal dentin, following the manufacturer instructions. Specimens were serially sectioned to obtain 1 mm thick beams in accordance with the μTBS test technique. Half of the beams were stressed to failure after 24 h (t = 0), while the other half were stored in artificial saliva for 12 months, at 37 °C, for ageing before stressing to failure (t = 12). Results: two-way ANOVA test showed significant difference for the factor “luting cement” (p = 0.0002), while the factor “time of storage” (p = 0.0991) had no significant effect on µTBS. Conclusions: PanaviaV5 seems to have better µTBS values at T0 than QM and ES and 1 year aging doesn’t seem to affect the bonding strength of tested systems.
UAV Image Multi-Labeling with Data-Efficient Transformers
Authors: Bashmal Laila , Bazi Yakoub , Al Rahhal Mohamad Mahmoud , Alhichri Haikel , Al Ajlan Naif
Published: April 2021

In this paper, we present an approach for the multi-label classification of remote sensing images based on data-efficient transformers. During the training phase, we generated a second view for each image from the training set using data augmentation. Then, both the image and its augmented version were reshaped into a sequence of flattened patches and then fed to the transformer encoder. The latter extracts a compact feature representation from each image with the help of a self-attention mechanism, which can handle the global dependencies between different regions of the high-resolution aerial image. On the top of the encoder, we mounted two classifiers, a token and a distiller classifier. During training, we minimized a global loss consisting of two terms, each corresponding to one of the two classifiers. In the test phase, we considered the average of the two classifiers as the final class labels. Experiments on two datasets acquired over the cities of Trento and Civezzano with a ground resolution of two-centimeter demonstrated the effectiveness of the proposed model.
Analysis of Tire Acoustic Cavity Resonance Energy Transmission Characteristics in Wheels Based on Power Flow Method
Authors: Zhao Wei , Liu Yuting , Liu Xiandong , Shan Yingchun , Hu Xiaojun
Published: April 2021

As a kind of low-frequency vehicle interior noise, tire acoustic cavity resonance noise plays an important role, since the other noise (e.g., engine noise, wind noise and friction noise) has been largely suppressed. For the suspension system, wheels stand first in the propagation path of this energy. Therefore, it is of great significance to study the influence of wheel design on the transmission characteristics of this vibration energy. However, currently the related research has not received enough attention. In this paper, two sizes of aluminum alloy wheel finite element models are constructed, and their modal characteristics are analyzed and verified by experimental tests simultaneously. A mathematically fitting sound pressure load model arising from the tire acoustic cavity resonance acting on the rim is first put forward. Then, the power flow method is applied to investigate the resonance energy distribution and transmission characteristics in the wheels. The structure intensity distribution and energy transmission efficiency can be described and analyzed clearly. Furthermore, the effects of material structure damping and the wheel spoke number on the energy transmission are also discussed.
Immunomodulatory Activity of Electrospun Polyhydroxyalkanoate Fiber Scaffolds Incorporating Olive Leaf Extract
Authors: De la Ossa Jose Gustavo , Fusco Alessandra , Azimi Bahareh , Esposito Salsano Jasmine , Digiacomo Maria , Coltelli Maria-Beatrice , De Clerck Karen , Roy Ipsita , Macchia Marco , Lazzeri Andrea , Donnarumma Giovanna , Danti Serena , Di Stefano Rossella
Published: April 2021

Olive tree is a well-known source of polyphenols. We prepared an olive leaf extract (OLE) and characterized it via high performance liquid chromatography (HPLC) analysis. OLE was blended with different polyhydroxyalkanoates (PHAs), namely, poly(hydroxybutyrate-co-hydroxyvalerate) (PHBHV) and polyhydroxybutyrate/poly(hydroxyoctanoate-co-hydroxydecanoate) (PHB/PHOHD), to produce fiber meshes via electrospinning: OLE/PHBV and OLE/ (PHB/PHOHD), respectively. An 80–90% (w/w%) release of the main polyphenols from the OLE/PHA fibers occurred in 24 h, with a burst release in the first 30 min. OLE and the produced fiber meshes were assayed using human dermal keratinocytes (HaCaT cells) to evaluate the expression of a panel of cytokines involved in the inflammatory process and innate immune response, such as the antimicrobial peptide human beta defensin 2 (HBD-2). Fibers containing OLE were able to decrease the expression of the pro-inflammatory cytokines at 6 h up to 24 h. All the PHA fibers allowed an early downregulation of the pro-inflammatory cytokines in 6 h, which is suggestive of a strong anti-inflammatory activity exerted by PHA fibers. Differently from pure OLE, PHB/PHOHD fibers (both with and without OLE) upregulated the expression of HBD-2. Our results showed that PHA fiber meshes are suitable in decreasing pro-inflammatory cytokines and the incorporation of OLE may enable indirect antibacterial properties, which is essential in wound healing and tissue regeneration.
Shoreline Response to Wave Forcing and Sea Level Rise along a Geomorphological Complex Coastline (Western Sardinia, Mediterranean Sea)
Authors: Simeone Simone , Palombo Luca , Molinaroli Emanuela , Brambilla Walter , Conforti Alessandro , De Falco Giovanni
Published: April 2021

Beaches responses to storms, as well as their potential adaptation to the foreseeable sea level rise (SLR), were investigated along three beaches in a coastal tract in western Sardinia (Western Mediterranean Sea). The grain size of the sediments, the beach profile variability and the wave climate were analyzed in order to relate morphological changes, geological inheritances and waves forcing. Multibeam, single-beam and lidar data were used to characterize the inner shelf morphologies and to reproduce the flooding due to the SLR. The studied beaches experienced major changes when consecutive storms, rather than singles ones, occurred along the coastline. The sediment availability, the grain size and the geomorphological structure of the beaches were the most important factors influencing the beach response. On the sediment-deprived coarse beaches the headlands favor the beach rotation, and the gravel barrier morphology can increase the resistance against storms. On the sediment-abundant beaches, the cross-shore sediment transport towards a submerged area leads to a lowering in the subaerial beach level and a contemporaneous shoreline retreat in response to storms. A very limited ingression of the sea is related to the SLR. This process may affect (i) the gravel barrier, promoting a roll over due to the increase in overwash; (ii) the embayed beach increasing its degree of embayment as headlands become more prominent, and (iii) the sediment-abundant beach with an erosion of the whole subaerial beach during storms, which can also involve the foredune area.
Sliding Balance Control of a Point-Foot Biped Robot Based on a Dual-Objective Convergent Equation
Authors: Lu Yizhou , Gao Junyao , Shi Xuanyang , Tian Dingkui , Liu Yi
Published: April 2021

The point-foot biped robot is highly adaptable to and can move rapidly on complex, non-structural and non-continuous terrain, as demonstrated in many studies. However, few studies have investigated balance control methods for point-foot sliding on low-friction terrain. This article presents a control framework based on the dual-objective convergence method and whole-body control for the point-foot biped robot to stabilize its posture balance in sliding. In this control framework, a dual-objective convergence equation is used to construct the posture stability criterion and the corresponding equilibrium control task, which are simultaneously converged. Control tasks are then carried out through the whole-body control framework, which adopts an optimization method to calculate the viable joint torque under the physical constraints of dynamics, friction and contact forces. In addition, this article extends the proposed approach to balance control in standing recovery. Finally, the capabilities of the proposed controller are verified in simulations in which a 26.9-kg three-link point-foot biped robot (1) slides over a 10∘ trapezoidal terrain, (2) slides on terrain with a sinusoidal friction coefficient between 0.05 and 0.25 and (3) stands and recovers from a center-of-mass offset of 0.02 m.
Integrated Optical Phased Arrays for Beam Forming and Steering
Authors: Guo Yongjun , Guo Yuhao , Li Chunshu , Zhang Hao , Zhou Xiaoyan , Zhang Lin
Published: April 2021

Integrated optical phased arrays can be used for beam shaping and steering with a small footprint, lightweight, high mechanical stability, low price, and high-yield, benefiting from the mature CMOS-compatible fabrication. This paper reviews the development of integrated optical phased arrays in recent years. The principles, building blocks, and configurations of integrated optical phased arrays for beam forming and steering are presented. Various material platforms can be used to build integrated optical phased arrays, e.g., silicon photonics platforms, III/V platforms, and III–V/silicon hybrid platforms. Integrated optical phased arrays can be implemented in the visible, near-infrared, and mid-infrared spectral ranges. The main performance parameters, such as field of view, beamwidth, sidelobe suppression, modulation speed, power consumption, scalability, and so on, are discussed in detail. Some of the typical applications of integrated optical phased arrays, such as free-space communication, light detection and ranging, imaging, and biological sensing, are shown, with future perspectives provided at the end.