bluuebunny/crossref_metadata_2025 huggingface dataset:
Current State of Breast Cancer Diagnosis, Treatment, and Theranostics
Authors: Bhushan Arya , Gonsalves Andrea , Menon Jyothi U.
Published: May 2021

Breast cancer is one of the leading causes of cancer-related morbidity and mortality in women worldwide. Early diagnosis and effective treatment of all types of cancers are crucial for a positive prognosis. Patients with small tumor sizes at the time of their diagnosis have a significantly higher survival rate and a significantly reduced probability of the cancer being fatal. Therefore, many novel technologies are being developed for early detection of primary tumors, as well as distant metastases and recurrent disease, for effective breast cancer management. Theranostics has emerged as a new paradigm for the simultaneous diagnosis, imaging, and treatment of cancers. It has the potential to provide timely and improved patient care via personalized therapy. In nanotheranostics, cell-specific targeting moieties, imaging agents, and therapeutic agents can be embedded within a single formulation for effective treatment. In this review, we will highlight the different diagnosis techniques and treatment strategies for breast cancer management and explore recent advances in breast cancer theranostics. Our main focus will be to summarize recent trends and technologies in breast cancer diagnosis and treatment as reported in recent research papers and patents and discuss future perspectives for effective breast cancer therapy.
Ileo-Colon Targeting of the Poorly Water-Soluble Drug Celecoxib Using a pH-Dependent Coating in Combination with Self-Emulsifying Drug Delivery or Solid Dispersion Systems
Authors: Broesder Annemarie , Berends Julia M. E. , Scheepers Sophie M. , Nguyen Duong N. , Frijlink Henderik W. , Hinrichs Wouter L. J.
Published: May 2021

Targeting celecoxib to the ileo-colonic region could be beneficial for the treatment and prevention of colon cancer. Ileo-colonic targeting can be achieved by using pH-dependent coating systems such as ColoPulse. Celecoxib has poor aqueous solubility, which may jeopardize optimal treatment. Therefore, we combined a pH-dependent coating with self-emulsifying drug delivery systems (SEDDS) or with solid dispersion systems (SD); two approaches that are often used to improve the dissolution behavior of lipophilic drugs. The dissolution behavior of various formulations of both systems was investigated. Optimized formulations with and without precipitation inhibitors were coated with the ColoPulse and the release of celecoxib was tested under non-sink conditions using an in vitro dissolution system, simulating the pH gradient of the gastrointestinal tract. The dissolution behavior of SDs with and without precipitation inhibitor (sodium dodecyl sulfate) and the SEDDS without precipitation inhibitor was negatively impacted by the coating. Control experiments indicated that components of the coating released in the dissolution medium acted as precipitation mediators. However, the SEDDS formulation with HPMC 4000 cps as a precipitation inhibitor showed excellent dissolution behavior. We hypothesize that HPMC accumulates at the oil/water interface of the emulsion thereby stabilizing the emulsion resulting in maintenance of the supersaturated state.
Seaweed Sulfated Polysaccharides against Respiratory Viral Infections
Authors: Jabeen Mehwish , Dutot Mélody , Fagon Roxane , Verrier Bernard , Monge Claire
Published: May 2021

Respiratory viral infections have been a leading cause of morbidity and mortality worldwide. Despite massive advancements in the virology field, no specific treatment exists for most respiratory viral infections. Approved therapies against respiratory viruses rely almost exclusively on synthetic drugs that have potential side effects, restricting their use. This review aims to present natural marine sulfated polysaccharides possessing promising antiviral activity against respiratory viruses that could be a safe alternative to synthetic broad-spectrum antiviral drugs. The antiviral properties of marine sulfated polysaccharides are presented according to their mechanism of action on different types and strains of respiratory viruses, and the potential limits of their use are discussed.
Combined Use of Structure Analysis, Studies of Molecular Association in Solution, and Molecular Modelling to Understand the Different Propensities of Dihydroxybenzoic Acids to Form Solid Phases
Authors: Trimdale Aija , Mishnev Anatoly , Bērziņš Agris
Published: May 2021

The arrangement of hydroxyl groups in the benzene ring has a significant effect on the propensity of dihydroxybenzoic acids (diOHBAs) to form different solid phases when crystallized from solution. All six diOHBAs were categorized into distinctive groups according to the solid phases obtained when crystallized from selected solvents. A combined study using crystal structure and molecule electrostatic potential surface analysis, as well as an exploration of molecular association in solution using spectroscopic methods and molecular dynamics simulations were used to determine the possible mechanism of how the location of the phenolic hydroxyl groups affect the diversity of solid phases formed by the diOHBAs. The crystal structure analysis showed that classical carboxylic acid homodimers and ring-like hydrogen bond motifs consisting of six diOHBA molecules are prominently present in almost all analyzed crystal structures. Both experimental spectroscopic investigations and molecular dynamics simulations indicated that the extent of intramolecular bonding between carboxyl and hydroxyl groups in solution has the most significant impact on the solid phases formed by the diOHBAs. Additionally, the extent of hydrogen bonding with solvent molecules and the mean lifetime of solute–solvent associates formed by diOHBAs and 2-propanol were also investigated.
Investigating the Potential of Transdermal Delivery of Avanafil Using Vitamin E-TPGS Based Mixed Micelles Loaded Films
Authors: Alamoudi Abdullah A. , Ahmed Osama A. A. , El-Say Khalid M.
Published: May 2021

To avoid the first-pass metabolism of avanafil (AVA) and its altered absorption in the presence of food after oral administration, this study aimed to investigate the potential of TPGS-based mixed micelle (MM)-loaded film for transdermal delivery and the enhancement of bioavailability. A Box–Behnken design was employed to optimize the permeation behavior of AVA from the transdermal film across the skin. The variables were the hydrophile-lipophile balance (HLB) of the surfactant (X1), the concentration of mixed micelles (MMs) in the film (X2), and the concentration of the permeation enhancer (X3). The initial permeation of AVA after 1 h (Y1), and the cumulative permeation of AVA after 24 h (Y2) were the dependent variables. Ex vivo studies were carried out on freshly isolated rat skin to investigate the drug’s permeation potential and results were visualized using a fluorescence laser microscope. Moreover, the pharmacokinetic behavior after a single application on male Wistar rats, in comparison with films loaded with raw AVA, was evaluated. The results showed that the optimum factor levels were 9.4% for the HLB of the surfactant used, and 5.12% MMs and 2.99% penetration enhancer in the film. Imaging with a fluorescence laser microscope indicated the ability of the optimized film to deliver the payload to deeper skin layers. Furthermore, optimized AVA-loaded TPGS-micelles film showed a significant increase (p < 0.05) in the Cmax of AVA and the area under the AVA plasma curve (approximately three-fold). The optimized AVA-loaded TPGS-MM film thus represents a successful delivery system for enhancing the bioavailability of AVA.
Spontaneous Curvature Induced Stretching-Bending Mode Coupling in Membranes
Authors: Kats Efim I.
Published: May 2021

In this paper, a simple example to illustrate what is basically known from the Gauss’ times interplay between geometry and mechanics in thin shells is presented. Specifically, the eigen-mode spectrum in spontaneously curved (i.e., up-down asymmetric) extensible polymerized or elastic membranes is studied. It is found that in the spontaneously curved crystalline membrane, the flexural mode is coupled to the acoustic longitudinal mode, even in the harmonic approximation. If the coupling (proportional to the membrane spontaneous curvature) is strong enough, the coupled modes dispersions acquire the imaginary part, i.e., effective damping. The damping is not related to the entropy production (dissipation); it comes from the redistribution of the energy between the modes. The curvature-induced mode coupling makes the flexural mode more rigid, and the acoustic mode becomes softer. As it concerns the transverse acoustical mode, it remains uncoupled in the harmonic approximation, keeping its standard dispersion law. We anticipate that the basic ideas inspiring this study can be applied to a large variety of interesting systems, ranging from still fashionable graphene films, both in the freely suspended and on a substrate states, to the not yet fully understood lipid membranes in the so-called gel and rippled phases.
Ureido Functionalization through Amine-Urea Transamidation under Mild Reaction Conditions
Authors: Guerrero-Alburquerque Natalia , Zhao Shanyu , Rentsch Daniel , Koebel Matthias M. , Lattuada Marco , Malfait Wim J.
Published: May 2021

Ureido-functionalized compounds play an indispensable role in important biochemical processes, as well as chemical synthesis and production. Isocyanates, and KOCN in particular, are the preferred reagents for the ureido functionalization of amine-bearing compounds. In this study, we evaluate the potential of urea as a reagent to graft ureido groups onto amines at relatively low temperatures (<100 °C) in aqueous media. Urea is an inexpensive, non-toxic and biocompatible potential alternative to KOCN for ureido functionalization. From as early as 1864, urea was the go-to reagent for polyurea polycondensation, before falling into disuse after the advent of isocyanate chemistry. We systematically re-investigate the advantages and disadvantages of urea for amine transamidation. High ureido-functionalization conversion was obtained for a wide range of substrates, including primary and secondary amines and amino acids. Reaction times are nearly independent of substrate and pH, but excess urea is required for practically feasible reaction rates. Near full conversion of amines into ureido can be achieved within 10 h at 90 °C and within 24 h at 80 °C, and much slower reaction rates were determined at lower temperatures. The importance of the urea/amine ratio and the temperature dependence of the reaction rates indicate that urea decomposition into an isocyanic acid or a carbamate intermediate is the rate-limiting step. The presence of water leads to a modest increase in reaction rates, but the full conversion of amino groups into ureido groups is also possible in the absence of water in neat alcohol, consistent with a reaction mechanism mediated by an isocyanic acid intermediate (where the water assists in the proton transfer). Hence, the reaction with urea avoids the use of toxic isocyanate reagents by in situ generation of the reactive isocyanate intermediate, but the requirement to separate the excess urea from the reaction product remains a major disadvantage.
Application of Computational Method in Designing a Unit Cell of Bone Tissue Engineering Scaffold: A Review
Authors: Mustafa Nur Syahirah , Akhmal Nor Hasrul , Izman Sudin , Ab Talib Mat Hussin , Shaiful Ashrul Ishak Mohamad , Omar Mohd Nazri Bin , Yahaya Nor Zaiazmin , Illias Suhaimi
Published: May 2021

The design of a scaffold of bone tissue engineering plays an important role in ensuring cell viability and cell growth. Therefore, it is a necessity to produce an ideal scaffold by predicting and simulating the properties of the scaffold. Hence, the computational method should be adopted since it has a huge potential to be used in the implementation of the scaffold of bone tissue engineering. To explore the field of computational method in the area of bone tissue engineering, this paper provides an overview of the usage of a computational method in designing a unit cell of bone tissue engineering scaffold. In order to design a unit cell of the scaffold, we discussed two categories of unit cells that can be used to design a feasible scaffold, which are non-parametric and parametric designs. These designs were later described and being categorised into multiple types according to their characteristics, such as circular structures and Triply Periodic Minimal Surface (TPMS) structures. The advantages and disadvantages of these designs were discussed. Moreover, this paper also represents some software that was used in simulating and designing the bone tissue scaffold. The challenges and future work recommendations had also been included in this paper.
Recent Progress in Antimicrobial Strategies for Resin-Based Restoratives
Authors: Sun Qiannan , Zhang Lingyun , Bai Rushui , Zhuang Zimeng , Zhang Yunfan , Yu Tingting , Peng Liying , Xin Tianyi , Chen Si , Han Bing
Published: May 2021

Repairing tooth defects with dental resin composites is currently the most commonly used method due to their tooth-colored esthetics and photocuring properties. However, the higher than desirable failure rate and moderate service life are the biggest challenges the composites currently face. Secondary caries is one of the most common reasons leading to repair failure. Therefore, many attempts have been carried out on the development of a new generation of antimicrobial and therapeutic dental polymer composite materials to inhibit dental caries and prolong the lifespan of restorations. These new antimicrobial materials can inhibit the formation of biofilms, reduce acid production from bacteria and the occurrence of secondary caries. These results are encouraging and open the doors to future clinical studies on the therapeutic value of antimicrobial dental resin-based restoratives. However, antimicrobial resins still face challenges such as biocompatibility, drug resistance and uncontrolled release of antimicrobial agents. In the future, we should focus on the development of more efficient, durable and smart antimicrobial dental resins. This article focuses on the most recent 5 years of research, reviews the current antimicrobial strategies of composite resins, and introduces representative antimicrobial agents and their antimicrobial mechanisms.
Approaches in Animal Proteins and Natural Polysaccharides Application for Food Packaging: Edible Film Production and Quality Estimation
Authors: Lisitsyn Andrey , Semenova Anastasia , Nasonova Viktoria , Polishchuk Ekaterina , Revutskaya Natalia , Kozyrev Ivan , Kotenkova Elena
Published: May 2021

Natural biopolymers are an interesting resource for edible films production, as they are environmentally friendly packaging materials. The possibilities of the application of main animal proteins and natural polysaccharides are considered in the review, including the sources, structure, and limitations of usage. The main ways for overcoming the limitations caused by the physico-chemical properties of biopolymers are also discussed, including composites approaches, plasticizers, and the addition of crosslinking agents. Approaches for the production of biopolymer-based films and coatings are classified according to wet and dried processes and considered depending on biopolymer types. The methods for mechanical, physico-chemical, hydration, and uniformity estimation of edible films are reviewed.
Mitigating Antibiotic Resistance Genes in Wastewater by Sequential Treatment with Novel Nanomaterials
Authors: Paruch Lisa , Paruch Adam M. , Iordache Tanta-Verona , Olaru Andreea G. , Sarbu Andrei
Published: May 2021

Wastewater (WW) has been widely recognized as the major sink of a variety of emerging pathogens (EPs), antibiotic-resistant bacteria (ARB) and antibiotic resistance genes (ARGs), which may disseminate and impact wider environments. Improving and maximizing WW treatment efficiency to remove these microbial hazards is fundamentally imperative. Despite a variety of physical, biological and chemical treatment technologies, the efficiency of ARG removal is still far from satisfactory. Within our recently accomplished M-ERA.NET project, novel functionalized nanomaterials, i.e., molecularly imprinted polymer (MIP) films and quaternary ammonium salt (QAS) modified kaolin microparticles, were developed and demonstrated to have significant EP removal effectiveness on both Gram-positive bacteria (GPB) and Gram-negative bacteria (GNB) from WW. As a continuation of this project, we took the further step of exploring their ARG mitigation potential. Strikingly, by applying MIP and QAS functionalized kaolin microparticles in tandem, the ARGs prevalent in wastewater treatment plants (WWTPs), e.g., blaCTXM, ermB and qnrS, can be drastically reduced by 2.7, 3.9 and 4.9 log (copies/100 mL), respectively, whereas sul1, tetO and mecA can be eliminated below their detection limits. In terms of class I integron-integrase I (intI1), a mobile genetic element (MGE) for horizontal gene transfer (HGT), 4.3 log (copies/100 mL) reduction was achieved. Overall, the novel nanomaterials exhibit outstanding performance on attenuating ARGs in WW, being superior to their control references. This finding provides additional merit to the application of developed nanomaterials for WW purification towards ARG elimination, in addition to the proven bactericidal effect.
Effect of Spherical Elements of Biosensors and Bioreactors on the Physicochemical Properties of a Peroxidase Protein
Authors: Ivanov Yuri D. , Tatur Vadim Yu. , Pleshakova Tatyana O. , Shumov Ivan D. , Kozlov Andrey F. , Valueva Anastasia A. , Ivanova Irina A. , Ershova Maria O. , Ivanova Nina D. , Repnikov Victor V. , Stepanov Igor N. , Ziborov Vadim S.
Published: May 2021

External electromagnetic fields are known to be able to concentrate inside the construction elements of biosensors and bioreactors owing to reflection from their surface. This can lead to changes in the structure of biopolymers (such as proteins), incubated inside these elements, thus influencing their functional properties. Our present study concerned the revelation of the effect of spherical elements, commonly employed in biosensors and bioreactors, on the physicochemical properties of proteins with the example of the horseradish peroxidase (HRP) enzyme. In our experiments, a solution of HRP was incubated within a 30 cm-diameter titanium half-sphere, which was used as a model construction element. Atomic force microscopy (AFM) was employed for the single-molecule visualization of the HRP macromolecules, adsorbed from the test solution onto mica substrates in order to find out whether the incubation of the test HRP solution within the half-sphere influenced the HRP aggregation state. Attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR) was employed in order to reveal whether the incubation of HRP solution within the half-sphere led to any changes in its secondary structure. In parallel, spectrophotometry-based estimation of the HRP enzymatic activity was performed in order to find out if the HRP active site was affected by the electromagnetic field under the conditions of our experiments. We revealed an increased aggregation of HRP after the incubation of its solution within the half-sphere in comparison with the control sample incubated far outside the half-sphere. ATR-FTIR allowed us to reveal alterations in HRP’s secondary structure. Such changes in the protein structure did not affect its active site, as was confirmed by spectrophotometry. The effect of spherical elements on a protein solution should be taken into account in the development of the optimized design of biosensors and bioreactors, intended for performing processes involving proteins in biomedicine and biotechnology, including highly sensitive biosensors intended for the diagnosis of socially significant diseases in humans (including oncology, cardiovascular diseases, etc.) at early stages.
Hardly Flammable Polyurethane Foams with 1,3-Pyrimidine Ring and Boron Atoms
Authors: Chmiel-Szukiewicz Elżbieta
Published: May 2021

This work presents the results of research related to the determination of application possibilities of new oligoetherols with 1,3-pyrimidine rings and boron atoms in rigid polyurethane foam production. Oligoetherols were obtained from 1,3-bis(2-hydroxyethyl)uracil, boric acid, and ethylene carbonate. Their structure was determined by instrumental methods (IR, 1H-NMR and MALDI-ToF spectra) and the physicochemical and thermal properties were examined. Obtained oligoetherols were used for synthesis of polyurethane foams. Some properties of the foams, such as apparent density, water uptake, dimensions stability, thermal stability, compression strength, thermal conductivity, oxygen index, and horizontal burning were investigated. The introduction of boron atoms into the foam structure reduced their flammability, but unfortunately it had a negative effect on the water absorption of the obtained materials—the water absorption was higher compared to the boron-free foams. The obtained foams showed good thermal stability compared to classic, rigid polyurethane foams.
From Amorphous Silicones to Si-Containing Highly Ordered Polymers: Some Romanian Contributions in the Field
Authors: Cazacu Maria , Racles Carmen , Zaltariov Mirela-Fernanda , Dascalu Mihaela , Bele Adrian , Tugui Codrin , Bargan Alexandra , Stiubianu George
Published: May 2021

Polydimethylsiloxane (PDMS), in spite of its well-defined helical structure, is an amorphous fluid even at extremely high molecular weights. The cause of this behavior is the high flexibility of the siloxane backbone and the lack of intermolecular interactions attributed to the presence of methyl groups. These make PDMS incompatible with almost any organic or inorganic component leading to phase separation in siloxane-siloxane copolymers containing blocks with polar organic groups and in siloxane-organic copolymers, where dimethylsiloxane segments co-exist with organic ones. Self-assembly at the micro- or nanometric scale is common in certain mixed structures, including micelles, vesicles, et cetera, manifesting reversibly in response to an external stimulus. Polymers with a very high degree of ordering in the form of high-quality crystals were obtained when siloxane/silane segments co-exist with coordinated metal blocks in the polymer chain. While in the case of coordination of secondary building units (SBUs) with siloxane ligands 1D chains are formed; when coordination is achieved in the presence of a mixture of ligands, siloxane and organic, 2D structures are formed in most cases. The Romanian research group’s results regarding these aspects are reviewed: from the synthesis of classic, amorphous silicone products, to their adaptation for use in emerging fields and to new self-assembled or highly ordered structures with properties that create perspectives for the use of silicones in hitherto unexpected areas.
Solvent Effect to the Uniformity of Surfactant-Free Salmon-DNA Thin Films
Authors: Richter Jake , Nnaji Moses , Park Heungman
Published: May 2021

Fabrication of surfactant-modified DNA thin films with high uniformity, specifically DNA–CTMA, has been well considered via drop-casting and spin-coating techniques. However, the fabrication of thin films with pure DNA has not been sufficiently studied. We characterize the uniformity of thin films from aqueous salmon DNA solutions mixed with ethanol, methanol, isopropanol, and acetone. Measurements of thickness and macroscopic uniformity are made via a focused-beam ellipsometer. We discuss important parameters for optimum uniformity and note what the effects of solvent modifications are. We find that methanol- and ethanol-added solutions provide optimal fabrication methods, which more consistently produce high degrees of uniformity with film thickness ranging from 20 to 200 nm adjusted by DNA concentration and the physical parameters of spin-coating methods.
Preparation of Porous Hydroxyapatite Using Cetyl Trimethyl Ammonium Bromide as Surfactant for the Removal of Lead Ions from Aquatic Solutions
Authors: Predoi Silviu-Adrian , Ciobanu Carmen Steluta , Motelica-Heino Mikael , Chifiriuc Mariana Carmen , Badea Monica Luminita , Iconaru Simona Liliana
Published: May 2021

In the present study, a new low-cost bioceramic nanocomposite based on porous hydroxyapatite (HAp) and cetyl trimethyl ammonium bromide (CTAB) as surfactant was successfully obtained by a simple chemical co-precipitation. The composition and structure of the HAp-CTAB were characterized by X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, transmission electron microscopy (TEM), scanning electron microscope (SEM) equipped with an energy dispersive X-ray (EDX) spectrometer, and N2 adsorption/desorption analysis. The capacity of HAp-CTAB nanocomposites to remove the lead ions from aqueous solutions was studied by adsorption batch experiments and proved by Langmuir and Freundlich models. The Pb2+ removal efficiency of HAp-CTAB biocomposite was also confirmed by non-destructive ultrasound studies. The cytotoxicity assays showed that the HAp-CTAB nanocomposites did not induce any significant morphological changes of HeLa cells after 24 h of incubation or other toxic effects. Taken together, our results suggests that the obtained porous HAp-CTAB powder could be used for the decontamination of water polluted with heavy metals, such as Pb2+.
Predicting the Adsorption of Amoxicillin and Ibuprofen on Chitosan and Graphene Oxide Materials: A Density Functional Theory Study
Authors: Anchique Leonardo , Alcázar Jackson J. , Ramos-Hernandez Andrea , Méndez-López Maximiliano , Mora José R. , Rangel Norma , Paz José Luis , Márquez Edgar
Published: May 2021

The occurrence, persistence, and accumulation of antibiotics and non-steroidal anti-inflammatory drugs (NSAIDs) represent a new environmental problem due to their harmful effects on human and aquatic life. A suitable absorbent for a particular type of pollutant does not necessarily absorb other types of compounds, so knowing the compatibility between a particular pollutant and a potential absorbent before experimentation seems to be fundamental. In this work, the molecular interactions between some pharmaceuticals (amoxicillin, ibuprofen, and tetracycline derivatives) with two potential absorbers, chitosan and graphene oxide models (pyrene, GO-1, and coronene, GO-2), were studied using the ωB97X-D/6-311G(2d,p) level of theory. The energetic interaction order found was amoxicillin/chitosan > amoxicillin/GO-1 > amoxicillin/GO-2 > ibuprofen/chitosan > ibuprofen/GO-2 > ibuprofen/GO-1, the negative sign for the interaction energy in all complex formations confirms good compatibility, while the size of Eint between 24–34 kcal/mol indicates physisorption processes. Moreover, the free energies of complex formation were negative, confirming the spontaneity of the processes. The larger interaction of amoxicillin Gos, compared to ibuprofen Gos, is consistent with previously reported experimental results, demonstrating the exceptional predictability of these methods. The second-order perturbation theory analysis shows that the amoxicillin complexes are mainly driven by hydrogen bonds, while van der Waals interactions with chitosan and hydrophobic interactions with graphene oxides are modelled for the ibuprofen complexes. Energy decomposition analysis (EDA) shows that electrostatic energy is a major contributor to the stabilization energy in all cases. The results obtained in this work promote the use of graphene oxides and chitosan as potential adsorbents for the removal of these emerging pollutants from water.
Trend of Modification by Autoclave at Low Pressure and by Natural Fermentation in Sweet Potato and Cassava Starches
Authors: Paixão e Silva Giselle de Lima , Bento Juliana Aparecida Correia , Soares Júnior Manoel Soares , Caliari Márcio
Published: May 2021

Sweet potatoes (Ipomoea batatas L.) and cassava (Manihot esculenta C.) are part of the largest food crops in many countries. They have good nutritional value because, in addition to containing vitamins, minerals, carotenoids, and anthocyanins in varied contents, due to the existence of various colors of their pulps, they have starch as their major constituent. As such, they are considered valuable raw materials for the food factory. The starch granules have distinct morphologies and properties, related to the type of cultivar, planting conditions, storage, and processing, which in turn can affect the quality of the final products to which they have been added. The use of native starches in the food industry has limitations, which can be improved by modifications. Physical methods, as they are associated with green technology, and do not pollute the environment, have demonstrated great potential for this purpose. Both modifications—by autoclave at low pressure and natural fermentation—have shown potential in modifying these starches.
How Loud Is Too Loud? Competing Rights to Religious Freedom and Property and the Muslim Call to Prayer (Adhan or Azan) in South Africa
Authors: Moosa Najma
Published: May 2021

This article approaches the position of the call to prayer (adhan or azan) in South Africa from the perspective of both legislation and case law. Although only an unamplified adhan has religious status in Islam, Muslim religious authorities (ulama) have since the twentieth century also approved of, and permitted, an amplified adhan. The adhan has been rendered in both forms from South African mosques (masjids) for some 223 years. However, the unamplified adhan has recently come under the legal and judicial spotlight when the volume of its rendering by human voice was restricted. In August 2020, after prior attempts at municipal level and mediation had been unsuccessful, a high court in KwaZulu-Natal, South Africa, ruled that the sound of the unamplified adhan emanating from a mosque located on the premises of an Islamic institution (madrassa) in the city of Durban should not be audible within the house situated on nearby property belonging to a Hindu neighbor. Wide media coverage reported that the ruling was publicly decried and met with criticism. The Madrassa lodged an appeal in September 2020 and the matter is ongoing. The High Court’s decision is binding in KwaZulu-Natal, a province where Hindus, as a religious minority, are concentrated. The article highlights that although the decision is not binding on similar courts in other provinces, its outcome may yet have far-reaching consequences for the adhan as a religious and cultural heritage symbol, and for religious symbols generally, because similar complaints have been lodged, albeit against amplified adhans, against several mosques located in major cities (Cape Town and Tshwane) of two other provinces where Muslims, as a religious minority, are largely concentrated. The article examines the adhan in the context of competing constitutional rights to religious freedom and property (neighbor law) in South Africa. The article proffers some recommendations for the way forward in South Africa based in some instances on the position of the adhan in several countries. It concludes that, ultimately, unamplified, unduly amplified and duly amplified adhans may all yet be found to constitute a noise nuisance in South Africa, if challenged and found to be unreasonable.
Multirobot Confidence and Behavior Modeling: An Evaluation of Semiautonomous Task Performance and Efficiency
Authors: Lucas Nathan , Pandya Abhilash
Published: May 2021

There is considerable interest in multirobot systems capable of performing spatially distributed, hazardous, and complex tasks as a team leveraging the unique abilities of humans and automated machines working alongside each other. The limitations of human perception and cognition affect operators’ ability to integrate information from multiple mobile robots, switch between their spatial frames of reference, and divide attention among many sensory inputs and command outputs. Automation is necessary to help the operator manage increasing demands as the number of robots (and humans) scales up. However, more automation does not necessarily equate to better performance. A generalized robot confidence model was developed, which transforms key operator attention indicators to a robot confidence value for each robot to enable the robots’ adaptive behaviors. This model was implemented in a multirobot test platform with the operator commanding robot trajectories using a computer mouse and an eye tracker providing gaze data used to estimate dynamic operator attention. The human-attention-based robot confidence model dynamically adapted the behavior of individual robots in response to operator attention. The model was successfully evaluated to reveal evidence linking average robot confidence to multirobot search task performance and efficiency. The contributions of this work provide essential steps toward effective human operation of multiple unmanned vehicles to perform spatially distributed and hazardous tasks in complex environments for space exploration, defense, homeland security, search and rescue, and other real-world applications.
Multi-Task Fusion Deep Learning Model for Short-Term Intersection Operation Performance Forecasting
Authors: Chen Deqi , Yan Xuedong , Liu Xiaobing , Wang Liwei , Li Fengxiao , Li Shurong
Published: May 2021

Urban road intersection bottleneck has become an important factor in causing traffic delay and restricting traffic efficiency. It is essential to explore the prediction of the operating performance at intersections in real-time and formulate corresponding strategies to alleviate intersection delay. However, because of the sophisticated intersection traffic condition, it is difficult to capture the intersection traffic Spatio-temporal features by the traditional data and prediction methods. The development of big data technology and the deep learning model provides us a good chance to address this challenge. Therefore, this paper proposes a multi-task fusion deep learning (MFDL) model based on massive floating car data to effectively predict the passing time and speed at intersections over different estimation time granularity. Moreover, the grid model and the fuzzy C-means (FCM) clustering method are developed to identify the intersection area and derive a set of key Spatio-temporal traffic parameters from floating car data. In order to validate the effectiveness of the proposed model, the floating car data from ten intersections of Beijing with a sampling rate of 3s are adopted for the training and test process. The experiment result shows that the MFDL model enables us to capture the Spatio-temporal and topology feature of the traffic state efficiently. Compared with the traditional prediction method, the proposed model has the best prediction performance. The interplay between these two targeted prediction variables can significantly improve prediction accuracy and efficiency. Thereby, this method predicts the intersection operation performance in real-time and can provide valuable insights for traffic managers to improve the intersection’s operation efficiency.
Group Target Tracking Based on MS-MeMBer Filters
Authors: Zhang Zhiguo , Sun Jinping , Zhou Huiyu , Xu Congan
Published: May 2021

This paper presents a new group target tracking method based on the standard multi-sensor multi-target multi-Bernoulli (MS-MeMBer) filter. In the prediction step, the group structure is used to constrain the movement of the constituent members within the respective groups. Specifically, the group of members is considered as an undirected random graph. Combined with the virtual leader-follower model, the motion equation of the members within groups is formulated. In the update step, the partitioning problem of multiple sensors is transformed into a multi-dimensional assignment (MDA) problem. Compared with the original two-step greedy partitioning mechanism, the MDA algorithm achieves better measurement partitions in group target tracking scenarios. To evaluate the performance of the proposed method, a simulation scenario including group splitting and merging is established. Results show that, compared with the standard MS-MeMBer filter, our method can effectively estimate the cardinality of members and groups at the cost of increasing computational load. The filtering accuracy of the proposed method outperforms that of the MS-MeMBer filter.
Subtask Attention Based Object Detection in Remote Sensing Images
Authors: Xiong Shengzhou , Tan Yihua , Li Yansheng , Wen Cai , Yan Pei
Published: May 2021

Object detection in remote sensing images (RSIs) is one of the basic tasks in the field of remote sensing image automatic interpretation. In recent years, the deep object detection frameworks of natural scene images (NSIs) have been introduced into object detection on RSIs, and the detection performance has improved significantly because of the powerful feature representation. However, there are still many challenges concerning the particularities of remote sensing objects. One of the main challenges is the missed detection of small objects which have less than five percent of the pixels of the big objects. Generally, the existing algorithms choose to deal with this problem by multi-scale feature fusion based on a feature pyramid. However, the benefits of this strategy are limited, considering that the location of small objects in the feature map will disappear when the detection task is processed at the end of the network. In this study, we propose a subtask attention network (StAN), which handles the detection task directly on the shallow layer of the network. First, StAN contains one shared feature branch and two subtask attention branches of a semantic auxiliary subtask and a detection subtask based on the multi-task attention network (MTAN). Second, the detection branch uses only low-level features considering small objects. Third, the attention map guidance mechanism is put forward to optimize the network for keeping the identification ability. Fourth, the multi-dimensional sampling module (MdS), global multi-view channel weights (GMulW) and target-guided pixel attention (TPA) are designed for further improvement of the detection accuracy in complex scenes. The experimental results on the NWPU VHR-10 dataset and DOTA dataset demonstrated that the proposed algorithm achieved the SOTA performance, and the missed detection of small objects decreased. On the other hand, ablation experiments also proved the effects of MdS, GMulW and TPA.
Evaluation of CFOSAT Scatterometer Wind Data in Global Oceans
Authors: Ye Haijun , Li Junmin , Li Bo , Liu Junliang , Tang Danling , Chen Wuyang , Yang Hongqiang , Zhou Fenghua , Zhang Rongwang , Wang Sufen , Tang Shilin
Published: May 2021

The China-France Oceanography SATellite (CFOSAT), launched on 29 October 2018, is a joint mission developed by China and France. To evaluate the CFOSAT wind product, L2B swath data with a spatial resolution of 25 × 25 km were compared with in situ measurements between December 2018 and December 2020. The in situ measurements were collected from 217 buoys. All buoy winds were adjusted to 10 m height using a simple logarithmic correction method. The temporal and spatial separations between the CFOSAT and in situ measurements were restricted to less than 30 min and 0.25°. The results indicate that the CFOSAT wind retrievals agree well with the buoy measurements. The root mean square errors (RMSEs) of wind vectors were 1.39 m s−1 and 34.32° and negligible biases were found. In the near shore under rain-free conditions, the RMSEs were enhanced to 1.42 m s−1 and 33.43°. Similarly, the RMSEs were reduced to 1.16 m s−1 and 30.41° offshore after the rain effect was removed. After winds less than 4 m s−1 were removed, the RMSE of wind directions was reduced to 19.69°. The effects of significant wave height, air-sea temperature difference, sea surface temperature, atmospheric pressure and ocean surface current on the wind residuals were assessed. The performance of wind retrievals under the passage of tropical cyclones was evaluated. The evaluation results show that the CFOSAT wind retrievals satisfy the accuracy requirements of scientific research, although some improvements are needed to enhance the performance.
Assessing an Atmospheric Correction Algorithm for Time Series of Satellite-Based Water-Leaving Reflectance Using Match-Up Sites in Australian Coastal Waters
Authors: Li Fuqin , Jupp David L. B. , Schroeder Thomas , Sagar Stephen , Sixsmith Joshua , Dorji Passang
Published: May 2021

An atmospheric correction algorithm for medium-resolution satellite data over general water surfaces (open/coastal, estuarine and inland waters) has been assessed in Australian coastal waters. In situ measurements at four match-up sites were used with 21 Landsat 8 images acquired between 2014 and 2017. Three aerosol sources (AERONET, MODIS ocean aerosol and climatology) were used to test the impact of the selection of aerosol optical depth (AOD) and Ångström coefficient on the retrieved accuracy. The initial results showed that the satellite-derived water-leaving reflectance can have good agreement with the in situ measurements, provided that the sun glint is handled effectively. Although the AERONET aerosol data performed best, the contemporary satellite-derived aerosol information from MODIS or an aerosol climatology could also be as effective, and should be assessed with further in situ measurements. Two sun glint correction strategies were assessed for their ability to remove the glint bias. The most successful one used the average of two shortwave infrared (SWIR) bands to represent sun glint and subtracted it from each band. Using this sun glint correction method, the mean all-band error of the retrieved water-leaving reflectance at the Lucinda Jetty Coastal Observatory (LJCO) in north east Australia was close to 4% and unbiased over 14 acquisitions. A persistent bias in the other strategy was likely due to the sky radiance being non-uniform for the selected images. In regard to future options for an operational sun glint correction, the simple method may be sufficient for clear skies until a physically based method has been established.
Maneuvering Target Detection Based on Subspace Subaperture Joint Coherent Integration
Authors: Zhao Langxu , Tao Haihong , Chen Weijia , Song Dawei
Published: May 2021

Range cell migration and Doppler frequency migration induced by the target maneuverability are two difficulties of target signal enhancement and radar detection performance. In order to resolve them, a novel subaperture joint coherent integration (SJCI) algorithm is proposed in this article, which consists of three stages. Firstly, it divides the target signal into several subapertures, in which the Doppler frequency dispersions can be neglected. Afterward, coherent integration within each subaperture is implemented via scaled Fourier transform. Finally, correcting the Doppler frequency shifts and phase differences via axis rotation and phase compensation technology, the joint coherent integration among the subapertures can be achieved effectively. Based on the SJCI algorithm, an upgrade algorithm named subspace SJCI (SSJCI) is presented. Through acceleration space division and subspace translation, the SSJCI algorithm extends the subaperture time and optimizes the computation complexity significantly. Theoretical analyses and performance comparisons demonstrate that the SSJCI algorithm can accomplish a good trade-off among signal-to-noise ratio gain, detection capability, resolution, and computation complexity. In addition, the results of the numerical experiments further verify the effectiveness of the proposed algorithm.
An Efficient Indoor Positioning Method Based on Wi-Fi RSS Fingerprint and Classification Algorithm
Authors: Ezhumalai Balaji , Song Moonbae , Park Kwangjin
Published: May 2021

Wi-Fi received signal strength (RSS) fingerprint-based indoor positioning has been widely used because of its low cost and universality advantages. However, the Wi-Fi RSS is greatly affected by multipath interference in indoor environments, which can cause significant errors in RSS observations. Many methods have been proposed to overcome this issue, including the average method and the error handling method, but these existing methods do not consider the ever-changing dynamics of RSS in indoor environments. In addition, traditional RSS-based clustering algorithms have been proposed in the literature, but they make clusters without considering the nonlinear similarity between reference points (RPs) and the signal distribution in ever-changing indoor environments. Therefore, to improve the positioning accuracy, this paper presents an improved RSS measurement technique (IRSSMT) to minimize the error of RSS observation by using the number of selected RSS and its median values, and the strongest access point (SAP) information-based clustering technique, which groups the RPs using their SAP similarity. The performance of this proposed method is tested by experiments conducted in two different experimental environments. The results reveal that our proposed method can greatly outperform the existing algorithms and improve the positioning accuracy by 89.06% and 67.48%, respectively.
A Study of Spatiotemporal Distribution of Mobility-On-Demand in Generating Pick-Up/Drop-Offs Location Placement
Authors: Gunawan Ryan K. , Susilawati
Published: May 2021

The location placement of pick-up/drop-offs of ride hailing usually only considers spatial distribution within a certain area. Previous studies often mapped out the potential hotspots for pick-up/drop-offs, benefitting the ride-hailing company and not considering the passengers. Therefore, in this study, we incorporated the spatiotemporal distribution of mobility-on-demand on generating pick-up/drop-off location placement using a genetic algorithm considering the walking distance and minimum demand data served within the radius. The data collected are analyzed through the clustering method, and the resulting cluster centers are fed into the location optimization algorithm. The genetic algorithm is used to optimize the location placement with the consideration of the user’s walking distance and demand. The algorithm is able to find an appropriate placement and determine reliable pick-up/drop-off stations within the study area based on observed spatiotemporal demand despite the difference in demand distribution through different time periods.
Working across Boundaries in Urban Land Use and Services Planning—Building Public Sector Capabilities for Digitalisation
Authors: Rönkkö Emilia , Herneoja Aulikki
Published: May 2021

This article addresses the challenges and capability gaps confronted by public administrations concerning digital transformation and the use of novel tools in the context of land use, facilities and urban services planning. The present state of planning and management processes in Finland is introduced and reflected through experimental piloting conducted in two Finnish cities. Participatory action research and design research methodology was utilised to identify the main challenges as well as unravel the possibilities of digital transformation in the context of public services planning. The resulting analysis revealed the critical importance of facilitating integrative policies and coordination when working across knowledge boundaries between administrative domains. The paper contributes to a wider theoretical and conceptual understanding, as it discusses the advantages and feasibility of digital tools as boundary objects for cross-sectoral work in smart, people-centred urban governance. The authors see this direction of research as a fruitful ground for further investigations within the interdisciplinary urban planning research context.