bluuebunny/crossref_metadata_2025 huggingface dataset:
Understanding the Role of External Facilitation to Drive Quality Improvement for Stroke Care in Hospitals
Authors: Thayabaranathan Tharshanah , Andrew Nadine E. , Grimley Rohan , Stroil-Salama Enna , Grabsch Brenda , Hill Kelvin , Cadigan Greg , Purvis Tara , Middleton Sandy , Kilkenny Monique F. , Cadilhac Dominique A. ,   on behalf of the Stroke123 Investigators and AuSCR Consortium
Published: August 2021

The use of external facilitation within the context of multicomponent quality improvement interventions (mQI) is growing. We aimed to evaluate the influence of external facilitation for improving the quality of acute stroke care. Clinicians from hospitals participating in mQI (Queensland, Australia) as part of the Stroke123 study were supported by external facilitators in a single, on-site workshop to review hospital performance against eight clinical processes of care (PoCs) collected in the Australian Stroke Clinical Registry (AuSCR) and develop an action plan. Remote support (i.e., telephone/email) after the workshop was provided. As part of a process evaluation for Stroke123, we recorded the number and mode of contacts between clinicians and facilitators; type of support provided; and frequency of self-directed, hospital-level stroke registry data reviews. Analysis: We measured the association between amount/type of external facilitation, (i) development of action plans, and (ii) adherence to PoCs before and after the intervention using AuSCR data from 2010 to 2015. In total, 14/19 hospitals developed an action plan. There was no significant difference in amount or type of external facilitator support provided between hospitals that did, and did not, develop an action plan. There was no relationship between the amount of external facilitation and change in adherence to PoCs. Most (95%) hospitals accessed stroke registry performance data. In the Stroke123 study, the amount or type of external facilitation did not influence action plan development, and the amount of support did not influence the changes achieved in adherence to PoCs. Remote support may not add value for mQI.
Defensive Medicine in the Management of Cesarean Delivery: A Survey among Italian Physicians
Authors: Fineschi Vittorio , Arcangeli Mauro , Di Fazio Nicola , Del Fante Zoe , Fineschi Benedetta , Santoro Paola , Frati Paola ,   Associazione Consulcesi Health and ONLUS Futura Ricerca
Published: August 2021

Background and Objectives: This study aims to contribute to the definition of the defensive medicine phenomenon between obstetricians and gynecologists, as well as to possible effects on the frequency of deliveries performed by cesarean sections (CS). Materials and Methods: a digital questionnaire was administered through a mail-list including 600 gynecological specialists (of these 168 doctors completed the test), both in public and private settings. It was made of twenty multiple choice questions, concerning their awareness about the practice of defensive medicine and the planning and execution of CS. All doctors involved received clear and complete information about the purpose of this study and about the organizations that received their answers. Analyses of variance and regression were performed to describe differences between groups and to estimate the relationships between variables. The value of p < 0.5 was considered statistically relevant. Results: our analysis revealed that most respondents are confident with the defensive medicine definition and characteristics. This survey confirmed that gynecologists fear legal actions promoted by their patients and therefore modulate their choices by implementing professional behaviors of so-called “defensive medicine”. This relates to a greater number of medical liability judgements, which more often concern omission or delayed execution of cesarean section, rather than unskillful surgical procedures. Conclusions: there are few data to support a relation between the high rate of CS and defensive medicine. Numerous scientific studies associated this CS rate with the phenomenon of defensive medicine. This practice is constantly growing in all medical areas, especially in high-risk specialties such as obstetrics and gynecology. Our study highlights physicians’ awareness of adopting defensive medicine behaviors in their clinical practice, affecting the choice of the type of delivery to be performed.
The Main Impacts of Infrastructure Works on Public Roads
Authors: Santos Eduardo A. N. e , Dutra Clézio T. de S. , Chinelli Christine K. , Hammad Ahmed W. A. , Haddad Assed N. , Soares Carlos A. P.
Published: August 2021

Infrastructure implementation and renovation in cities require work on public roads that impact the daily lives of road users and local population and commerce. Although the study of the impacts of infrastructure works in the researched literature has received various approaches, there is still a shortage of studies that identify the impacts of the implementation of infrastructure on public roads and the importance of each one. This study collaborates with this theme by researching the main impacts caused by infrastructure works on public roads based on extensive and detailed bibliographic research and based on a survey carried out toward residents of the areas impacted by these works, road users, and Brazilian professionals with experience in the concerned field. The results showed that fourteen impacts identified in the literature were considered important by survey respondents, of which seven were considered the most important.
Lateral and Overturning Resistance of Wind Turbine Foundations Reinforced with Piles on Bedrock by Modelling Experiments
Authors: Kang Gichun , Yun Seong-Kyu , Kim Tae-Hyung , Kim Jiseong
Published: August 2021

This study evaluated the lateral and overturning resistance of wind turbine foundations reinforced with piles on bedrock through model experiments. In particular, changes in lateral and overturning resistance of wind turbine foundations were analyzed according to cross-sectional size and the presence of piles of wind turbine foundations. As a result, by reducing the cross-section, the lateral resistance of the pile-reinforced wind turbine foundation was compared to the existing wind turbine foundation with large cross-sections and was shown to be 1.68 times greater. In the case of vertical displacements affecting overturning, the safety of overturning was also greater, as the vertical displacement of the pile-reinforced wind turbine foundation was 36% smaller than the existing wind turbine foundation. As a result of the unidirectional cyclic load on a pile-reinforced wind turbine foundation, lateral resistance value was similar to that of the static load in target displacement value, and it showed that the elastic resilience was very large due to pile reinforcement. According to the bending moment measurement of piles embedded in wind turbine foundations and bedrock, bending moments were large in the order of the front row, the right-hand row, and the back row, while the maximum bending moment generation was found on the boundary surface of the wind turbine foundation and the rubble mound layer for the front row, as well as on the boundary surface of the rubble mound layer and bedrock for the right-hand row and back row.
On the Duality of Marine Geoheritage: Evidence from the Abrau Area of the Russian Black Sea Coast
Authors: Ruban Dmitry A.
Published: August 2021

Marine geoheritage is an important but still underdeveloped concept. Field investigations in the Abrau area (Krasnodar Region, southwestern Russia) and subsequent interpretations allow for the characterization of its geoheritage. Two geosites, namely Abrau and Limanchik, are delineated and assessed semi-qualitatively. Their high heritage value, complexity, and appropriate “technical” properties are appraised. The Abrau geosite features Abrau Lake with its enigmatic origin and the outcrops of deformed Upper Cretaceous carbonate flysch deposits. The Limanchik geosite represents an outstanding example of coastal abrasion, Paleocene siliciclastic flysch with trace fossils, and a coastal lagoon separated from the sea by a bar. The heritage aspects of the study areas are related to the development of the Late Cretaceous, Paleocene, and Pliocene seas, as well as to the active dynamics of the Black Sea coastal zone. The duality of marine geoheritage is linked to its relation to both ancient and modern marine environments.
Stochastic Analysis and Neural Network-Based Yield Prediction with Precision Agriculture
Authors: Shoshi Humayra , Hanson Erik , Nganje William , SenGupta Indranil
Published: August 2021

In this paper, we propose a general mathematical model for analyzing yield data. The data analyzed in this paper come from a characteristic corn field in the upper midwestern United States. We derive expressions for statistical moments from the underlying stochastic model. Consequently, we illustrate how a particular feature variable contributes to the statistical moments (and in effect, the characteristic function) of the target variable (i.e., yield). We also analyze the data with neural network techniques and provide two methods of data analysis. This mathematical model and neural network-based data analysis allow for better understanding of the variability within the data set, which is useful to farm managers attempting to make current and future decisions using the yield data. Lenders and risk management consultants may benefit from the insights of this mathematical model and neural network-based data analysis regarding yield expectations.
Utility Indifference Option Pricing Model with a Non-Constant Risk-Aversion under Transaction Costs and Its Numerical Approximation
Authors: Pólvora Pedro , Ševčovič Daniel
Published: August 2021

Our goal is to analyze the system of Hamilton-Jacobi-Bellman equations arising in derivative securities pricing models. The European style of an option price is constructed as a difference of the certainty equivalents to the value functions solving the system of HJB equations. We introduce the transformation method for solving the penalized nonlinear partial differential equation. The transformed equation involves possibly non-constant the risk aversion function containing the negative ratio between the second and first derivatives of the utility function. Using comparison principles we derive useful bounds on the option price. We also propose a finite difference numerical discretization scheme with some computational examples.
COVID-19 Mortality Prediction Using Machine Learning-Integrated Random Forest Algorithm under Varying Patient Frailty
Authors: Cornelius Erwin , Akman Olcay , Hrozencik Dan
Published: August 2021

The abundance of type and quantity of available data in the healthcare field has led many to utilize machine learning approaches to keep up with this influx of data. Data pertaining to COVID-19 is an area of recent interest. The widespread influence of the virus across the United States creates an obvious need to identify groups of individuals that are at an increased risk of mortality from the virus. We propose a so-called clustered random forest approach to predict COVID-19 patient mortality. We use this approach to examine the hidden heterogeneity of patient frailty by examining demographic information for COVID-19 patients. We find that our clustered random forest approach attains predictive performance comparable to other published methods. We also find that follow-up analysis with neural network modeling and k-means clustering provide insight into the type and magnitude of mortality risks associated with COVID-19.
Preparation of Cross-linked Chitosan Quaternary Ammonium Salt Hydrogel Films Loading Drug of Gentamicin Sulfate for Antibacterial Wound Dressing
Authors: Zhang Jingjing , Tan Wenqiang , Li Qing , Liu Xiaorui , Guo Zhanyong
Published: August 2021

Hydrogels, possessing high biocompatibility and adaptability to biological tissue, show great usability in medical applications. In this research, a series of novel cross-linked chitosan quaternary ammonium salt loading with gentamicin sulfate (CTMCSG) hydrogel films with different cross-linking degrees were successfully obtained by the reaction of chitosan quaternary ammonium salt (TMCS) and epichlorohydrin. Fourier transform infrared spectroscopy (FTIR), thermal analysis, and scanning electron microscope (SEM) were used to characterize the chemical structure and surface morphology of CTMCSG hydrogel films. The physicochemical property, gentamicin sulphate release behavior, cytotoxicity, and antibacterial activity of the CTMCSG against Escherichia coli and Staphylococcus aureus were determined. Experimental results demonstrated that CTMCSG hydrogel films exhibited good water stability, thermal stability, drug release capacity, as well as antibacterial property. The inhibition zone of CTMCSG hydrogel films against Escherichia coli and Staphylococcus aureus could be up to about 30 mm. Specifically, the increases in maximum decomposition temperature, mechanical property, water content, swelling degree, and a reduction in water vapor permeability of the hydrogel films were observed as the amount of the cross-linking agent increased. The results indicated that the CTMCSG-4 hydrogel film with an interesting physicochemical property, admirable antibacterial activity, and slight cytotoxicity showed the potential value as excellent antibacterial wound dressing.
Adsorption-Enhanced Ceramic Membrane Filtration Using Fenton Oxidation for Advanced Treatment of Refinery Wastewater: Treatment Efficiency and Membrane-Fouling Control
Authors: Mu Haotian , Qiu Qi , Cheng Renzhen , Qiu Liping , Xie Kang , Gao Mingchang , Liu Guicai
Published: August 2021

With the development of the refining industry, the treatment of refinery wastewater has become an urgent problem. In this study, a ceramic membrane (CM) was combined with Fenton-activated carbon (AC) adsorption to dispose of refinery wastewater. The effect of the combined process was analyzed using excitation–emission matrix (EEM), ultraviolet-visible (UV-vis) and Fourier transform infrared spectroscopies (FTIR). Compared with direct filtration, the combined process could significantly improve the removal of organic pollution, where the removal rate of the COD and TOC could be 70% and the turbidity removal rate was above 97%. It was found that the effluent could meet the local standards. In this study, the membrane fouling was analyzed for the impact of the pretreatment on the membrane direction. The results showed that Fenton-AC absorption could effectively alleviate membrane fouling. The optimal critical flux of the combined process was increased from 60 to 82 L/(m2·h) compared with direct filtration. After running for about 20 d, the flux remained at about 55 L/(m2·h) and the membrane-fouling resistance was only 1.2 × 1012 m−1. The Hermia model revealed that cake filtration was present in the early stages of the combined process. These results could be of great use in improving the treatment efficiency and operation cycle of refinery wastewater.
Feline Coronaviruses Identified in Feline Effusions in Suspected Cases of Feline Infectious Peritonitis
Authors: Yen Shih-Jung , Chen Hui-Wen
Published: August 2021

Ninety-five effusion samples were collected from cats with suspected feline infectious peritonitis in northern Taiwan; these samples showed a 47.4% (45/95) feline coronavirus (FCoV) positivity rate on immunofluorescence staining and RT-PCR. Young cats (≤24 months old) were found to have a significantly higher risk than cats >24 months old (odds ratio (OR) = 6.19, 95% confidence interval (CI) 2.54–16.00). No significant association was found between the positive rates and sex or breed. The A/G ratio in positive cases was significantly lower than the A/G ratio in negative cases. Genotyping and sequencing of the positive cases revealed 71.9% single infection with type I strains and 28.1% coinfection with types I and II. No single infections with type II strains were noted. The type I sequences had high diversity, while the type II sequences had high internal sequence identity and were more similar to CoVs from other species, such as dogs, pigs, and various small mammals. This study demonstrates the latest analysis of FCoV infection cases in northern Taiwan.
Asymmetric 1,4-Michael Addition Reaction of Azadienes with α-Thiocyanoindanones Catalyzed by Bifunctional Chiral Squaramide
Authors: Dong Xiao-Yan , Du Da-Ming
Published: August 2021

In this paper, the organocatalytic asymmetric 1,4-Michael addition reaction of azadienes and α-thiocyanoindanones was investigated. A series of chiral benzofuran compounds containing thiocyano group and quaternary carbon center were synthesized in moderate yields with good enantioselectivities (up to 90:10 er) and high diastereoselectivities (up to >95:5 dr). This is the first case of 1,4-Michael addition reaction using α-thiocyanoindanones to obtain a series of chiral thiocyano compounds and further broaden the scope of application of azadiene substrates. In addition, a possible reaction mechanism is also described in the article.
Synthesis and Antimycobacterial Activity of 3-Phenyl-1H-indoles
Authors: Jardim Etchart Renata , Rambo Raoní S. , Lopes Abbadi Bruno , Sperotto Nathalia , Ev Neves Christiano , Fries Silva Fernanda , Dornelles Maiele , Duarte Lovaine , Souza Macchi Fernanda , Alberton Perelló Marcia , Vescia Lourega Rogério , Valim Bizarro Cristiano , Basso Luiz Augusto , Machado Pablo
Published: August 2021

Tuberculosis has been described as a global health crisis since the 1990s, with an estimated 1.4 million deaths in the last year. Herein, a series of 20 1H-indoles were synthesized and evaluated as in vitro inhibitors of Mycobacterium tuberculosis (Mtb) growth. Furthermore, the top hit compounds were active against multidrug-resistant strains, without cross-resistance with first-line drugs. Exposing HepG2 and Vero cells to the molecules for 72 h showed that one of the evaluated structures was devoid of apparent toxicity. In addition, this 3-phenyl-1H-indole showed no genotoxicity signals. Finally, time-kill and pharmacodynamic model analyses demonstrated that this compound has bactericidal activity at concentrations close to the Minimum Inhibitory Concentration, coupled with a strong time-dependent behavior. To the best of our knowledge, this study describes the activity of 3-phenyl-1H-indole against Mtb for the first time.
Phosphate-Based Self-Immolative Linkers for the Delivery of Amine-Containing Drugs
Authors: Đud Mateja , Tichotová Markéta , Procházková Eliška , Baszczyňski Ondřej
Published: August 2021

Amine-containing drugs often show poor pharmacological properties, but these disadvantages can be overcome by using a prodrug approach involving self-immolative linkers. Accordingly, we designed l-lactate linkers as ideal candidates for amine delivery. Furthermore, we designed linkers bearing two different cargos (aniline and phenol) for preferential amine cargo release within 15 min. Since the linkers carrying secondary amine cargo showed high stability at physiological pH, we used our strategy to prepare phosphate-based prodrugs of the antibiotic Ciprofloxacin. Therefore, our study will facilitate the rational design of new and more effective drug delivery systems for amine-containing drugs.
Impacting the Remedial Potential of Nano Delivery-Based Flavonoids for Breast Cancer Treatment
Authors: Sindhu Rakesh K. , Verma Rishu , Salgotra Twinkle , Rahman Md. Habibur , Shah Muddaser , Akter Rokeya , Murad Waheed , Mubin Sidra , Bibi Parveen , Qusti Safaa , Alshammari Eida M. , Batiha Gaber El-Saber , Tomczyk Michał , Al-kuraishy Hayder M.
Published: August 2021

Breast cancer persists as a diffuse source of cancer despite persistent detection and treatment. Flavonoids, a type of polyphenol, appear to be a productive option in the treatment of breast cancer, because of their capacity to regulate the tumor related functions of class of compounds. Plant polyphenols are flavonoids that appear to exhibit properties which are beneficial for breast cancer therapy. Numerous epidemiologic studies have been performed on the dynamic effect of plant polyphenols in the prevention of breast cancer. There are also subclasses of flavonoids that have antioxidant and anticarcinogenic activity. These can regulate the scavenging activity of reactive oxygen species (ROS) which help in cell cycle arrest and suppress the uncontrolled division of cancer cells. Numerous studies have also been performed at the population level, one of which reported a connection between cancer risk and intake of dietary flavonoids. Breast cancer appears to show intertumoral heterogeneity with estrogen receptor positive and negative cells. This review describes breast cancer, its various factors, and the function of flavonoids in the prevention and treatment of breast cancer, namely, how flavonoids and their subtypes are used in treatment. This review proposes that cancer risk can be reduced, and that cancer can be even cured by improving dietary intake. A large number of studies also suggested that the intake of fruit and vegetables is associated with reduced breast cancer and paper also includes the role and the use of nanodelivery of flavonoids in the healing of breast cancer. In addition, the therapeutic potential of orally administered phyto-bioactive compounds (PBCs) is narrowed because of poor stability and oral bioavailability of compounds in the gastrointestinal tract (GIT), and solubility also affects bioavailability. In recent years, creative nanotechnology-based approaches have been advised to enhance the activity of PBCs. Nanotechnology also offers the potential to become aware of disease at earlier stages, such as the detection of hidden or unconcealed metastasis colonies in patients diagnosed with lung, colon, prostate, ovarian, and breast cancer. However, nanoformulation-related effects and safety must not be overlooked. This review gives a brief discussion of nanoformulations and the effect of nanotechnology on herbal drugs.
A–X⋯σ Interactions—Halogen Bonds with σ-Electrons as the Lewis Base Centre
Authors: Grabowski Sławomir J.
Published: August 2021

CCSD(T)/aug-cc-pVTZ//ωB97XD/aug-cc-pVTZ calculations were performed for halogen-bonded complexes. Here, the molecular hydrogen, cyclopropane, cyclobutane and cyclopentane act as Lewis base units that interact through the electrons of the H–H or C–C σ-bond. The FCCH, ClCCH, BrCCH and ICCH species, as well as the F2, Cl2, Br2 and I2 molecular halogens, act as Lewis acid units in these complexes, interacting through the σ-hole localised at the halogen centre. The Quantum Theory of Atoms in Molecules (QTAIM), the Natural Bond Orbital (NBO) and the Energy Decomposition Analysis (EDA) approaches were applied to analyse these aforementioned complexes. These complexes may be classified as linked by A–X···σ halogen bonds, where A = C, X (halogen). However, distinct properties of these halogen bonds are observed that depend partly on the kind of electron donor: dihydrogen, cyclopropane, or another cycloalkane. Examples of similar interactions that occur in crystals are presented; Cambridge Structural Database (CSD) searches were carried out to find species linked by the A–X···σ halogen bonds.
When UDG and hAPE1 Meet Cyclopurines. How (5′R) and (5′S) 5′,8-Cyclo-2′-deoxyadenosine and 5′,8-Cyclo-2′-deoxyguanosine Affect UDG and hAPE1 Activity?
Authors: Szewczuk Michał , Boguszewska Karolina , Kaźmierczak-Barańska Julia , Karwowski Bolesław T.
Published: August 2021

Ionizing radiation is a factor that seriously damages cellular mechanisms/macromolecules, e.g., by inducing damage in the human genome, such as 5′,8-cyclo-2′-deoxypurines (cdPus). CdPus may become a component of clustered DNA lesions (CDL), which are notably unfavorable for the base excision repair system (BER). In this study, the influence of 5′S and 5′R diastereomers of 5′,8-cyclo-2′-deoxyadenosine (cdA) and 5′,8-cyclo-2′-deoxyguanosine (cdG) on the uracil-DNA glycosylase (UDG) and human AP site endonuclease 1 (hAPE1) activity has been taken under consideration. Synthetic oligonucleotides containing 2′-deoxyuridine (dU) and cdPu were used as a model of single-stranded CDL. The activity of the UDG and hAPE1 enzymes decreased in the presence of RcdG compared to ScdG. Contrary to the above, ScdA reduced enzyme activity more than RcdA. The presented results show the influence of cdPus lesions located within CDL on the activity of the initial stages of BER dependently on their position toward dU. Numerous studies have shown the biological importance of cdPus (e.g., as a risk of carcinogenesis). Due to that, it is important to understand how to recognize and eliminate this type of DNA damage from the genome.
Junipers of Various Origins as Potential Sources of the Anticancer Drug Precursor Podophyllotoxin
Authors: Ivanova Diana I. , Nedialkov Paraskev T. , Tashev Alexander N. , Olech Marta , Nowak Renata , Ilieva Yana E. , Kokanova-Nedialkova Zlatina K. , Atanasova Teodora N. , Angelov George , Najdenski Hristo M.
Published: August 2021

Juniper representatives are natural sources of plenty of bioactive metabolites and have been used since ancient times as folk remedies against tapeworms, warts, cancer, etc. The antiproliferative activities of junipers are attributed to podophyllotoxin (PPT), which is a precursor for the synthesis of efficient anticancer drugs. However, the natural sources of PPT, Sinopodophyllum hexandrum (Royle) T. S. Ying and Podophyllum peltatum L., are already endangered species because of their intensive industrial exploitation. Therefore, identification of other sources of PPT is necessary. This study is a broad comparative investigation of junipers, for which original sources have been accessed from different continents of the world. The present research is aimed at the identification of species, producing PPT and other lignans at concentrations that are sufficient for the high antiproliferative activity of the corresponding extracts. Cytotoxic juniper leaf extracts demonstrated a broad spectrum of activity on a panel of cancer cell lines. The antiproliferative properties of junipers were attributed to the combined activity of great diversity of lignans (podophyllotoxin, deoxypodophyllotoxin, β-peltatin, yatein, matairesinol, anhydropodorhizol, etc.), detected by UHPLC-HRMS and LC-ESI-MS/MS in the corresponding extracts. Several species of the genus Juniperus L. were outlined as perspective sources of drug precursors with potential pharmaceutical applications.
A Narrative Review of the Current Knowledge on Fruit Active Aroma Using Gas Chromatography-Olfactometry (GC-O) Analysis
Authors: Egea Mariana Buranelo , Bertolo Mirella Romanelli Vicente , Oliveira Filho Josemar Gonçalves de , Lemes Ailton Cesar
Published: August 2021

Fruit aroma, a mixture of chemical compounds with odor, is a strong attractant derived from a complex mixture of different amounts and intensities (threshold) of chemical compounds found in fruits. The odor-producing compounds of fruit aroma are derived from carbohydrates, lipids, phenolic compounds, and mono- and sesquiterpenes, among others. The identification of compounds responsible for fruit aroma is usually conducted using gas chromatography coupled with olfactometry (GC-O). This technique separates the chemical compounds from the aroma of foods using a chromatographic column and divides the resultant outflow between the physical detector and a testing outlet (sniffing port). Trained judges describe the perceived odor in terms of the intensity of the odor zones perceived according to their training method. Moreover, the use of GC-O coupled with a mass detector (GC-MS-O) allows for the retrieval of chemical information such as identification and quantification of compounds, which can be correlated to sensory information. This review aimed to demonstrate the application of GC-MS-O in the identification of precursor compounds in fruit aroma, considering important factors for the application, main results, and most recent advances in this field.
Recent Advances on Pt-Free Electro-Catalysts for Dye-Sensitized Solar Cells
Authors: Huang Yi-June , Sahoo Prasanta Kumar , Tsai Dung-Sheng , Lee Chuan-Pei
Published: August 2021

Since Prof. Grätzel and co-workers achieved breakthrough progress on dye-sensitized solar cells (DSSCs) in 1991, DSSCs have been extensively investigated and wildly developed as a potential renewable power source in the last two decades due to their low cost, low energy-intensive processing, and high roll-to-roll compatibility. During this period, the highest efficiency recorded for DSSC under ideal solar light (AM 1.5G, 100 mW cm−2) has increased from ~7% to ~14.3%. For the practical use of solar cells, the performance of photovoltaic devices in several conditions with weak light irradiation (e.g., indoor) or various light incident angles are also an important item. Accordingly, DSSCs exhibit high competitiveness in solar cell markets because their performances are less affected by the light intensity and are less sensitive to the light incident angle. However, the most used catalyst in the counter electrode (CE) of a typical DSSC is platinum (Pt), which is an expensive noble metal and is rare on earth. To further reduce the cost of the fabrication of DSSCs on the industrial scale, it is better to develop Pt-free electro-catalysts for the CEs of DSSCs, such as transition metallic compounds, conducting polymers, carbonaceous materials, and their composites. In this article, we will provide a short review on the Pt-free electro-catalyst CEs of DSSCs with superior cell compared to Pt CEs; additionally, those selected reports were published within the past 5 years.
Conditional Cooperativity in DNA Minor-Groove Recognition by Oligopeptides
Authors: Lah Jurij , Hadži San
Published: August 2021

The recognition of specific DNA sequences in processes such as transcription is associated with a cooperative binding of proteins. Some transcription regulation mechanisms involve additional proteins that can influence the binding cooperativity by acting as corepressors or coactivators. In a conditional cooperativity mechanism, the same protein can induce binding cooperativity at one concentration and inhibit it at another. Here, we use calorimetric (ITC) and spectroscopic (UV, CD) experiments to show that such conditional cooperativity can also be achieved by the small DNA-directed oligopeptides distamycin and netropsin. Using a global thermodynamic analysis of the observed binding and (un)folding processes, we calculate the phase diagrams for this system, which show that distamycin binding cooperativity is more pronounced at lower temperatures and can be first induced and then reduced by increasing the netropsin or/and Na+ ion concentration. A molecular interpretation of this phenomenon is suggested.
Optical Frequency Combs Generated in Silica Microspheres in the Telecommunication C-, U-, and E-Bands
Authors: Anashkina Elena A. , Marisova Maria P. , Salgals Toms , Alnis Janis , Lyashuk Ilya , Leuchs Gerd , Spolitis Sandis , Bobrovs Vjaceslavs , Andrianov Alexey V.
Published: August 2021

Optical frequency combs (OFCs) generated in microresonators with whispering gallery modes are demanded for different applications including telecommunications. Extending operating spectral ranges is an important problem for wavelength-division multiplexing systems based on microresonators. We demonstrate experimentally three spectrally separated OFCs in the C-, U-, and E-bands in silica microspheres which, in principle, can be used for telecommunication applications. For qualitative explanation of the OFC generation in the sidebands, we calculated gain coefficients and gain bandwidths for degenerate four-wave mixing (FWM) processes. We also attained a regime when the pump frequency was in the normal dispersion range and only two OFCs were generated. The first OFC was near the pump frequency and the second Raman-assisted OFC with a soliton-like spectrum was in the U-band. Numerical simulation based on the Lugiato–Lefever equation was performed to support this result and demonstrate that the Raman-assisted OFC may be a soliton.
Extending the Dialogical Array
Authors: Yaguri Tami , Mooney Edward F.
Published: August 2021

The I-You dialogue of mutually reciprocal engagement makes a difference of heaven and hell. In the first out of four suggested types of I-You dialogue discussed in this article, all the I’s—of the primary word I-You—own a dialogical perspective. In the other three, it is the I who has an experience of creating and engaging in a dialogue that shortly achieves some kind of mutuality with You. Epistemologically, the four suggested types differ by the qualities of the I who engages in dialogue. The second stance is an I-You dialogue of sympathy. A third possibility is an I-You dialogue of empathy. A fourth possibility aims higher to a dialogue that transcends human mutuality by compassion and reaches a heavenly dialogue.
A Three-Phase Current Tacholess Envelope Order Analysis Method for Feature Extraction of Planetary Gearbox under Variable Speed Conditions
Authors: Zhang Xun , Xu Guanghua , Kuang Jiachen , Suo Lin , Zhang Sicong , Khalique Umair
Published: August 2021

Planetary gearboxes are the key components of large equipment, such as wind turbines, shield machines, etc. The operating state of the planetary gearbox is related to the safety of the equipment as a whole, and its feature extraction technology is essential. In assessing the problem of the non-stationarity of the current signal under variable speed conditions and the difficulty of evaluating the operating state of the planetary gearbox under a tacholess condition, a three-phase current, variable-speed tacholess envelope order analysis method is proposed. Firstly, a tacholess rotation speed estimation is completed by extracting the trend term of the instantaneous frequency of the asynchronous motor’s three-phase currents. The motor slip rate is assumed to be constant. Then, the envelope order analysis signal is obtained by re-sampling in the angular domain. Finally, the features of the envelope order signal are extracted, and a linear discriminant analysis (LDA) algorithm is used to fuse multiple indexes to generate a comprehensive feature reflecting the operating status of the planetary gearbox. The results of the simulation analysis and experimental verification show that the proposed method is effective in evaluating the operating state of the planetary gearbox under variable speed conditions. Compared with the traditional time–frequency ridge extraction method, the tacholess speed estimation method can improve the instantaneous speed estimation accuracy. The comprehensive index of envelope order completes the planetary gearbox state identification process, and a 95% classification accuracy rate is achieved.
Authorizing Third-Party Applications Served through Messaging Platforms
Authors: Sancho Jorge , García José , Alesanco Álvaro
Published: August 2021

The widespread adoption of smartphones and the new-generation wireless networks have changed the way that people interact among themselves and with their environment. The use of messaging platforms, such as WhatsApp, has become deeply ingrained in peoples’ lives, and many digital services have started to be delivered using these communication channels. In this work, we propose a new OAuth grant type to be used when the interaction between the resource owner and the client takes place through a messaging platform. This new grant type firstly allows the authorization server to be sure that no Man-in-the-Middle risk exists between the resource owner and the client before issuing an access token. Secondly, it allows the authorization server to interact with the resource owner through the same user-agent already being used to interact with the client, i.e., the messaging platform, which is expected to improve the overall user experience of the authorization process. To verify this assumption, we conducted a usability study in which subjects were required to perform the full authorization process using both the standard authorization code grant type (through a web-browser) and the new grant type defined in this work. They have also been required to fill in a small questionnaire including some demographic information and their impressions about both authorization flows. The results suggest that the proposed grant type eases the authorization process in most cases.
High Accurate Mathematical Tools to Estimate the Gravity Direction Using Two Non-Orthogonal Inclinometers
Authors: Mortari Daniele , Gardner Anthony
Published: August 2021

This study provides two mathematical tools to best estimate the gravity direction when using a pair of non-orthogonal inclinometers whose measurements are affected by zero-mean Gaussian errors. These tools consist of: (1) the analytical derivation of the gravity direction expectation and its covariance matrix, and (2) a continuous description of the geoid model correction as a linear combination of a set of orthogonal surfaces. The accuracy of the statistical quantities is validated by extensive Monte Carlo tests and the application in an Extended Kalman Filter (EKF) has been included. The continuous geoid description is needed as the geoid represents the true gravity direction. These tools can be implemented in any problem requiring high-precision estimates of the local gravity direction.
The Simulation of In-Situ Groundwater Detector Response as a Means of Identifying Beta Emitting Radionuclides by Linear Regression Analysis
Authors: Turkington Graeme , Gamage Kelum A. A. , Graham James
Published: August 2021

The in-situ characterisation of strontium-90 contamination of groundwater at nuclear decommissioning sites would represent a novel and cost-saving technology for the nuclear industry. However, beta particles are emitted over a continuous spectrum and it is difficult identify radionuclides due to the overlap of their spectra and the lack of characteristic features. This can be resolved by using predictive modelling to perform a maximum-likelihood estimation of the radionuclides present in a beta spectrum obtained with a semiconductor detector. This is achieved using a linear least squares linear regression and relating experimental data with simulated detector response data. In this case, by simulating a groundwater borehole scenario and the deployment of a cadmium telluride detector within it, it is demonstrated that it is possible to identify the presence of 90Sr, 90Y, 137Cs and 235U decay. It is determined that the optimal thickness of the CdTe detector for this technique is in the range of 0.1 to 1 mm. The influence of suspended solids in the groundwater is also investigated. The average and maximum concentrations of suspended particles found at Sellafield do not significantly deteriorate the results. It is found that applying the linear regression over two energy windows improves the estimate of 90Sr activity in a mixed groundwater source. These results provide validation for the ability of in-situ detectors to determine the activity of 90Sr in groundwater in a timely and cost-effective manner.
Influence of Dispersed Oil on the Remote Sensing Reflectance—Field Experiment in the Baltic Sea
Authors: Haule Kamila , Toczek Henryk , Borzycka Karolina , Darecki Mirosław
Published: August 2021

Remote sensing techniques currently used to detect oil spills have not yet demonstrated their applicability to dispersed forms of oil. However, oil droplets dispersed in seawater are known to modify the local optical properties and, consequently, the upwelling light flux. Theoretically possible, passive remote detection of oil droplets was never tested in the offshore conditions. This study presents a field experiment which demonstrates the capability of commercially available sensors to detect significant changes in the remote sensing reflectance Rrs of seawater polluted by six types of dispersed oils (two crude oils, cylinder lubricant, biodiesel, and two marine gear lubricants). The experiment was based on the comparison of the upwelling radiance Lu measured in a transparent tank floating in full immersion in seawater in the Southern Baltic Sea. The tank was first filled with natural seawater and then polluted by dispersed oils in five consecutive concentrations of 1–15 ppm. After addition of dispersed oils, spectra of Rrs noticeably increased and the maximal increase varied from 40% to over three-fold at the highest oil droplet concentration. Moreover, the most affected Rrs band ratios and band differences were analyzed and are discussed in the context of future construction of algorithms for dispersed oil detection.
Morphological Characteristics of the Sperm of the Peregrine Falcon (Falco peregrinus) during the Reproductive Season
Authors: Oliveira Andrea , Martínez Felisa , Gil Lydia , Luño Victoria
Published: August 2021

The morphological characteristics of different sperm cells (normal, abnormal, and immature) in the peregrine falcon during the reproductive season were analysed. We also classified the main sperm defects found in semen. Semen samples were collected from mature peregrine falcons via cloacal massage and stained with Diff-Quik stain. The percentages of normal, abnormal, and immature sperm cells were determined by bright-field optical microscopy. The number of normal spermatozoa were greater at the initial stage and subsequently decreased during the middle and later stages of the reproductive season (p < 0.01). In contrast, the percentage of abnormal spermatozoa increased significantly in the middle and end stages of the reproductive season (p < 0.05), whereas the proportion of immature spermatozoa remained stable during the study. Head defects represented the greatest proportion of morphological abnormalities, followed by the defects in the tail and midpiece regions. A small percentage of multiple defects and cytoplasmic droplets were also observed in the falcon spermatozoa. The findings of this study might be important for the development of future conservation protocols for falcon sperm.
Methods and means for digital transformation of physical objects
Authors: Ivanova Yoana
Published: August 2021

The research aims to present main methods of digital transformations of physical objects by the means for 3D modelling and 3D scanning. Emphasis is placed on the advantages of laser scanning and the nature of the triangulation methods on which it is based. It is explained how the reliability of the obtained results depends on the calibration process that precedes the 3D scanning of a physical object. Special attention is paid to the technical and software preparation that precedes the 3D scanning process. The practical research is realized using a physical object suitable in terms of construction, shape and size. For the digital transformations is purposefully chosen a real existing spherical robot, which serves as a basis for comparison in assessing the effectiveness of the described methods, as well as the quality and realism of the obtained digital models. The scientific and applied contributions are expressed in a comparative analysis of practical methods, which contains an algorithm of steps suitable for educational purposes for the implementation of the described work processes.
The choice of bachelor’s program in telecommunications and computer technology
Authors: Stefanova Tereza
Published: August 2021

The aim of the article is to show the influence of the graduated secondary education for the choice of the bachelor's program "Telecommunications and Computer Technology" from the Telecommunication’s Department, NBU. The article presents some of the results of a survey conducted among students of the bachelor's program. The presented data are for students who started their education during the academic years from 2016 to 2019. As a result of the study, it was found that the students enrolled in the bachelor's program most often have graduated from vocational technical high schools in this field. Together with graduates of other vocational high schools, they are approximately half of the students who choose this bachelor's program.The study will contribute to anticipating the preliminary preparation of students who have chosen a bachelor's program in "Telecommunications and Computer Technology" and to improve their future education.
Approach for analysis and modeling of reliability of network connectivity from the perspective of efficiency and its applicability
Authors: Simeonova Tsvetelina
Published: August 2021

Reliability analysis and assessment methods can be used at any stage of system or component design, including development, operation, and maintenance. Fault Tree-based models and reliability block diagram RBD (qualitative and quantitative) are typically used to provide reliability and readiness assessments for both the early and later stages of design, where system models are more -improved and have more detailed specifications compared to the models of the early stage of the system. On the other hand, models based on the Markov Chain are mainly used in the later design phase. The aim of the work is to define ways to use methods for modeling reliability, with a subsequent goal for analysis taking into account the effectiveness. An approach for modeling the end-to-end network connectivity with different reservations of the connection lines is considered. The results are illustrated by graphical ratios at different influencing parameters, for different reservation methods. A comparative analysis was made using different reservation methods. The practical applicability of the proposed approach and the performed analysis, incl. for training purposes.
The features of land relations regulation in the border areas of the Russian Federation
Authors: Gusev A.A. , Golovko O.V.
Published: August 2021

The article discusses the problems and features of the legislative regulation of the turnover of land in the border areas of the Russian Federation. Possible solutions are proposed for a more rational use of resources.

English version of the article is available on pp. 80-83 at URL: https://panor.ru/articles/features-of-land-relations-regulation-in-the-border-territories-of-the-russian-federation/66551.html
La correspondencia entre J. Maritain y É. Gilson en 1923. Precisiones en torno a la segunda edición de El tomismo
Authors: Muñoz Ceferino P. D. , Heiremans Correa Juan
Published: August 2021

El siguiente escrito muestra el breve pero enjundioso intercambio epistolar entre quizás los dos filósofos cristianos más importantes del siglo XX: Étienne Gilson y Jacques Maritain. Las cartas están centradas en torno a algunas de las tantas temáticas que inquietaron a los tomistas del siglo pasado –la intuición de Dios, el primer objeto de la inteligencia, la función propia del intelecto humano, entre otras– y que aun muestran su plena actualidad en el debate contemporáneo. Ofrecemos la primera traducción al español de las cartas enviadas en el año 1923 –inicio de una fructífera correspondencia entre ambos filósofos–, con ocasión de la publicación de la segunda edición de El tomismo, uno de los libros más emblemáticos de Gilson.