bluuebunny/crossref_metadata_2025 huggingface dataset:
Quantitative Prediction of Sea Clutter Power Based on Improved Grey Markov Model
Authors: Chen Zihao , Tian Bin , Zhang Siyun , Xu Quanjun
Published: July 2022

The detection and prediction of sea clutter power is the basis of inversing atmospheric duct. At present, the technology of atmospheric duct within radar detection range is relatively perfect, but the long-distance inversion of atmospheric duct is limited by radar detection range, and the prediction of the echo power of the measured sea clutter is the basis of long-distance inversion of atmospheric duct. Based on the theory of weighted Markov model and grey Markov model, a weighted grey Markov model is constructed, and the sliding method is introduced to establish the sliding weighted grey Markov model. The relative error between the measured sea clutter power and predicted values of the above four models is calculated and analyzed using the experimental data collected. The results show that the sliding weighted grey Markov model has better accuracy not only in short-range prediction but also in long-distance prediction, which could provide data support for inversing atmospheric duct.
Exploring Role Behavior in Restaurant by Grey Model and Grey Structural Model
Authors: Chen Joyce-Hsiu-Yu , Wu Shu-Hua , Lin Ping-Min , Chang Hsueh-Feng
Published: July 2022

Based on GM (0,N) grey model and grey structure model in grey system theory, this study takes Chinese restaurant in tourist hotel as a case to analyze service role behavior. A total of 241 questionnaires were collected to calculate index weighted coefficients, and then 12 experts carried out an investigation to construct clusters. There were 12 dimensions of professional competencies, and a total of 50 indicator factors were analyzed for role behavior in a restaurant. According to the results, there are three role behaviors for service staff in Chinese restaurants: supportive, interactive, and integrative role behaviors. In theory, this reinterprets the meaning of catering service competencies and defines the role types of catering service staff. In practical applications, restaurant managers could apply this result to help service staff to understand their current role, in order to reduce their role pressure and to increase their job satisfaction and performance.
Actuator and Contact Force Modeling of an Active Soft Brace for Scoliosis
Authors: Ali Athar , Fontanari Vigilio , Schmoelz Werner , Fontana Marco
Published: July 2022

Scoliosis is an abnormality of the spinal curvature that severely affects the musculoskeletal, respiratory, and nervous systems. Conventionally, it is treated using rigid spinal braces. These braces are static, rigid, and passive in nature, and they (largely) limit the mobility of the spine, resulting in other spinal complexities. Moreover, these braces do not have precise control over how much force is being applied by them. Over-exertion of force may deteriorate the spinal condition. This article presents a novel active soft brace that allows mobility to the spine while applying controlled corrective forces that are regulated by varying the tensions in elastic bands using low-power light weight twisted string actuators (TSAs). This article focuses on the actuator and contact force modeling of the active soft brace (ASB). The actuator modeling is required to translate the twisting of string in terms of contraction of the string’s length, whereas the contact force modeling helps in estimating the net resultant force exerted by the band on the body using single point pressure/force sensors. The actuators (TSAs) are modeled as helix geometry and validated using a laser position sensor. The results showed that the model effectively tracked the position (contraction in length) with root mean square error (RMSE) of 1.7386 mm. The contact force is modeled using the belt and pulley contact model and validated by building a custom testbed. The actuator module is able to regulate the pressure in the range 0–6 Kpa, which is comparable to 0–8 Kpa pressure regulated in rigid braces. This makes it possible to verify and demonstrate the working principle of the proposed active soft brace.
Editorial for the Special Issue: “State-of-Art in Protein Engineering”
Authors: Petrovskaya Lada E. , Dolgikh Dmitry A.
Published: July 2022

This Special Issue of Biomolecules demonstrates the almost unlimited possibilities of modern protein engineering in gene expression, protein production and modification, as well as the design and creation of new proteins [...]
All-in-One Optofluidic Chip for Molecular Biosensing Assays
Authors: Sano Tyler , Zhang Han , Losakul Ravipa , Schmidt Holger
Published: July 2022

Integrated biosensor platforms have become subjects of high interest for consolidated assay preparation and analysis to reduce sample-to-answer response times. By compactly combining as many biosensor processes and functions as possible into a single lab-on-chip device, all-in-one point-of-care devices can aid in the accessibility and speed of deployment due to their compact size and portability. Biomarker assay preparation and sensing are functionalities that are often carried out on separate devices, thus increasing opportunity of contamination, loss of sample volume, and other forms of error. Here, we demonstrate a complete lab-on-chip system combining sample preparation, on-chip optofluidic dye laser, and optical detection. We first show the integration of an on-chip distributed feedback dye laser for alignment-free optical excitation of particles moving through a fluidic channel. This capability is demonstrated by using Rhodamine 6G as the gain medium to excite single fluorescent microspheres at 575 nm. Next, we present an optofluidic PDMS platform combining a microvalve network (automaton) for sample preparation of nanoliter volumes, on-chip distributed feedback dye laser for target excitation, and optical detection. We conduct concurrent capture and fluorescence tagging of Zika virus nucleic acid on magnetic beads in 30 min. Target-carrying beads are then optically excited using the on-chip laser as they flow through an analysis channel, followed by highly specific fluorescence detection. This demonstration of a complete all-in-one biosensor is a tangible step in the development of a rapid, point-of-care device that can assist in limiting the severity of future outbreaks.
Mxenes–Au NP Hybrid Plasmonic 2D Microplates in Microfluidics for SERS Detection
Authors: Chen Zhaoxian , Liu Anping , Zhang Xiumei , Jiao Jiawei , Yuan Yuan , Huang Yingzhou , Yan Sheng
Published: July 2022

Combined with microfluidics, surface-enhanced Raman spectroscopy (SERS) exhibits huge application prospective in sensitive online detection. In current studies, the design and optimization of plasmonic enhanced structures in microfluidics for SERS detection could be an interesting challenge. In this work, hybrid plasmonic 2D microplates composed of Mxenes (Ti3C2Tx) microplates and in-situ synthesized Au nanoparticles (Au NPs) are fabricated in a microchannel for enhanced structures in SERS microfluidics. Benefiting from the 2D Mxenes microplates with complex distributions, the enhanced areas generated by Au NPs are quite enlarged in a microchannel, which exhibits high sensitivity in SERS detection at 10−10 M for Nile blue (NB) molecules in microfluidics. The mechanism of electromagnetic enhancement (EM) and chemical enhancement (CM) is analyzed. The experimental data indicate the ultrasonic times of Mxenes and the concentration of Au3+ play important roles in the sensitivity of SERS detection, which is confirmed by the simulated electric field distributions. Furthermore, a typical pesticide (thiram) at 100 ppm in water is detected on these SERS microfluidics with hybrid plasmonic enhanced structures, which demonstrates that our work not only strengthens the knowledge of plasmonics but also enlarges the application of SERS.
Documentation and Inheritance of Ancient Opera Stage Based on Multidisciplinary Approach and Digital Technology
Authors: Zhang Xiao , Zhang Aiwu , Xu Jiaqi , Ma Rongqing
Published: July 2022

The survival and longevity of architectural heritage, especially structures in isolated locations such as ancient opera stages, have been gradually threatened by natural and sociocultural changes over the past few decades. Furthermore, the future of these heritage sites remains uncertain. Therefore, in this study, we aimed to develop a research method, using multidisciplinary knowledge and digital technology, to digitally protect and inherit the endangered heritage of ancient stages. Hence, in this study, we applied a qualitative longitudinal method for digital protection, digital culture inheritance, and data intelligence management. Particularly, digital culture inheritance established the knowledge visualization model, which was used to excavate cultural connotations and was displayed with virtual reality, augmented reality, etc. Furthermore, a GIS digital platform was developed to provide data management and a virtual experience in a 3D-interactive way for culture presentation, cognition, and heritage. Then, the developed method was validated over four years by using the ancient opera stages in Shanxi, China, as case studies. The results demonstrate that this method is feasible in and applicable to the heritages of ancient stages and can be applied to other architectural heritages and even cultural heritages. This method also helps to promote the public’s awareness of the protection of cultural heritage, especially the heritages of ancient stages.
Reinforced Effect on Brick Wall Using Timber Wall as a Retrofitting Method
Authors: Ganbaatar Ariunaa , Mori Takuro , Matsumoto Shinya , Inoue Ryo
Published: July 2022

The purpose of this study is to utilize timber material to enhance the in-plane shear strength and deformation capacity of a brick wall. The proposed strengthening method is light-weight and easy to assemble and includes a timber frame, plywood panel, M12 threaded rod with chemical epoxy, and the hold-down anchor. To evaluate the effectiveness of the reinforced brick wall, three walls were tested under a cyclic horizontal load and static compression stress: the brick wall (BW wall), the reinforced brick wall with timber (BW-T wall), and the reinforced brick wall with timber and the hold-down anchor (BW-TA wall). The proposed prediction method of the Kamiya and Inayama Murakami models assessed the BW-TA wall. The rocking was caused by the failure of BW and BW-T walls. However, because the BW-T wall failed in the lowest part of the wall, the timber part retained the original shape of the brick wall. When the diagonal on the BW-TA wall failed, the horizontal load at maximum load increased by 22%, and the drift angle calculated from the diagonal measurement increased 4.6 times.
Numerical Analysis of the Seismic Performance of Light-Frame Timber Buildings Using a Detailed Model
Authors: Benedetti Franco , Jara-Cisterna Alan , Grandón Juan Carlos , Astroza Nicool , Opazo-Vega Alexander
Published: July 2022

Timber structures have gained interest for the construction of mid-rise buildings, but their seismic performance is still a matter under development. In this study, a numerical analysis of the seismic performance of light-frame timber buildings is developed through a highly detailed model using parallel computing tools. All of the lateral-load-resisting system components and connections are modeled. Combinations of lateral load capacity distributions in structures of one, three, and five stories are studied in order to assess the effects on the global performance of different triggered failure modes through nonlinear static and dynamic analyses. The results suggest that shear bracket connections and sheathing-to-framing connections control the buildings’ responses, as well as the failure mode. For a ductile response, the lateral displacement must be dominated by the in-plane wall distortion (racking); therefore, the system must be provided with a story shear sliding stiffness and load capacity at least twice that of the walls. Furthermore, based on the pushover capacity curves, the performance limits are proposed by evaluating the stiffness degradation. Finally, the effect of the mobilized failure mode on the structural fragility is analyzed. Even though standard desktop PCs are used in this research, significant reductions in the computation effort are achieved.
Stromal Co-Cultivation for Modeling Breast Cancer Dormancy in the Bone Marrow
Authors: Wieder Robert
Published: July 2022

Cancers metastasize to the bone marrow before primary tumors can be detected. Bone marrow micrometastases are resistant to therapy, and while they are able to remain dormant for decades, they recur steadily and result in incurable metastatic disease. The bone marrow microenvironment maintains the dormancy and chemoresistance of micrometastases through interactions with multiple cell types and through structural and soluble factors. Modeling dormancy in vitro can identify the mechanisms of these interactions. Modeling also identifies mechanisms able to disrupt these interactions or define novel interactions that promote the reawakening of dormant cells. The in vitro modeling of the interactions of cancer cells with various bone marrow elements can generate hypotheses on the mechanisms that control dormancy, treatment resistance and reawakening in vivo. These hypotheses can guide in vivo murine experiments that have high probabilities of succeeding in order to verify in vitro findings while minimizing the use of animals in experiments. This review outlines the existing data on predominant stromal cell types and their use in 2D co-cultures with cancer cells.
Validation of “Self-Evaluation of Communication Experiences after Laryngectomy” (SECEL) Questionnaire for Spanish-Speaking Laryngectomized Patients
Authors: Villanueva Eva , Fernández María Paula , Arena Giovanna , Llorente José L. , Rodrigo Juan P. , López Fernando , Álvarez-Marcos César
Published: July 2022

Background: Laryngectomized patients have communicative limitations when they lose their phonatory function after surgery. The scale “Self-Evaluation of Communication Experiences after Laryngectomy” (SECEL) assesses the impact of total laryngectomy on quality of life related to communication. The aim of this study was to translate and adapt the SECEL from English to Spanish and to apply this first version to a group of patients to check its reliability and validity. Materials and Methods: One-hundred-and-one laryngectomized patients completed the SECEL scale adjusted to Spanish, the Voice Handicap Index (VHI-30), the Hospital Anxiety and Depression Scale (HADS) and the EORTC QLQ-H&N35 questionnaire. Results: The Spanish version of the SECEL questionnaire has the same format and conceptual, semantic and idiomatic meaning as the original. The resulting model is composed of 21 items dimensioned in two highly correlated factors that are clear, meaningful, and replicable leading to measures that are reliable enough to be used in clinical evaluation. Conclusion: The Spanish translation and validation of the SECEL questionnaire were performed. It can be considered an appropriate tool to assess communication skills from laryngectomized people.
CISH Expression Is Associated with Metastasis-Free Interval in Triple-Negative Breast Cancer and Refines the Prognostic Value of PDL1 Expression
Authors: Boudin Laurys , De Nonneville Alexandre , Finetti Pascal , Guittard Geoffrey , Nunes Jacques A. , Birnbaum Daniel , Mamessier Emilie , Bertucci François
Published: July 2022

Strategies are being explored to increase the efficiency of immune checkpoint inhibitors (ICIs) targeting PD1/PDL1 in triple-negative breast cancer (TNBC), including combination with therapies inhibiting intracellular immune checkpoints such as CISH (Cytokine-induced SH2 protein). Correlation between CISH expression and TNBC features is unknown. We retrospectively analyzed CISH expression in 1936 clinical TNBC samples and searched for correlations with clinical variables, including metastasis-free interval (MFI). Among TNBCs, 44% were identified as “CISH-up” and 56% “CISH-down”. High expression was associated with pathological axillary lymph node involvement, more adjuvant chemotherapy, and Lehmann’s immunomodulatory and luminal AR subtypes. The “CISH-up” class showed longer 5-year MFI (72%) than the “CISH-down” class (60%; p = 2.8 × 10−2). CISH upregulation was associated with activation of IFNα and IFNγ pathways, antitumor cytotoxic immune response, and signatures predictive for ICI response. When CISH and PDL1 were upregulated together, the 5-year MFI was 81% versus 52% when not upregulated (p = 6.21 × 10−6). The two-gene model provided more prognostic information than each gene alone and maintained its prognostic value in multivariate analysis. CISH expression is associated with longer MFI in TNBC and refines the prognostic value of PDL1 expression. Such observation might reinforce the therapeutic relevance of combining CISH inhibition with an anti-PD1/PDL1 ICI.
Different Effects of Salt Bridges near the Active Site of Cold-Adapted Proteus mirabilis Lipase on Thermal and Organic Solvent Stabilities
Authors: Dachuri VinayKumar , Jang Sei-Heon , Lee ChangWoo
Published: July 2022

Organic solvent-tolerant (OST) enzymes have been discovered in psychrophiles. Cold-adapted OST enzymes exhibit increased conformational flexibility in polar organic solvents resulting from their intrinsically flexible structures. Proteus mirabilis lipase (PML), a cold-adapted OST lipase, was used to assess the contribution of salt bridges near the active site involving two arginine residues (R237 and R241) on the helix η1 and an aspartate residue (D248) on the connecting loop to the thermal and organic solvent stabilities of PML. Alanine substitutions for the ion pairs (R237A, R241A, D248A, and R237A/D248A) increased the conformational flexibility of PML mutants compared to that of the wild-type PML in an aqueous buffer. The PML mutants became more susceptible to denaturation after increasing the dimethyl sulfoxide or methanol concentration than after a temperature increase. Methanol was more detrimental to the structural stability of PML compared to dimethyl sulfoxide. These results suggest that direct interactions of dimethyl sulfoxide and methanol with the residues near the active site can have a destructive effect on the structure of PML compared with the global effect of heat on the protein structure. This study provides insight into the conformational changes within an OST enzyme with different effects on its thermal and organic solvent stabilities.
Human Basal and Suprabasal Keratinocytes Are Both Able to Generate and Maintain Dermo–Epidermal Skin Substitutes in Long-Term In Vivo Experiments
Authors: Pontiggia Luca , Ahuja Akshay Kumar , Yosef Hesham Kamaleldin , Rütsche Dominic , Reichmann Ernst , Moehrlen Ueli , Biedermann Thomas
Published: July 2022

The basal layer of human interfollicular epidermis has been described to harbour both quiescent keratinocyte stem cells and a transit amplifying cell population that maintains the suprabasal epidermal layers. We performed immunofluorescence analyses and revealed that the main proliferative keratinocyte pool in vivo resides suprabasally. We isolated from the human epidermis two distinct cell populations, the basal and the suprabasal keratinocytes, according to the expression of integrin β4 (iβ4). We compared basal iβ4+ or suprabasal iβ4− keratinocytes with respect to their proliferation and colony-forming ability and their Raman spectral properties. In addition, we generated dermo–epidermal substitutes using freshly isolated and sorted basal iβ4+ or suprabasal iβ4− keratinocytes and transplanted them on immuno-compromised rats. We show that suprabasal iβ4− keratinocytes acquire a similar proliferative capacity as basal iβ4+ keratinocytes after two weeks of culture in vitro, with expression of high levels of iβ4 and downregulation of K10 expression. In addition, both basal iβ4+ and suprabasal iβ4− keratinocytes acquire authentic self-renewing properties during the in vitro 3D-culture phase and are able to generate and maintain a fully stratified epidermis for 16 weeks in vivo. Therefore, against the leading dogma, we propose that human suprabasal keratinocytes can retro-differentiate into true basal stem cells in a wound situation and/or when in contact with the basement membrane.
Masculinizer and Doublesex as Key Factors Regulate Sexual Dimorphism in Ostrinia furnacalis
Authors: Bi Honglun , Li Xiaowei , Xu Xia , Wang Yaohui , Zhou Shutang , Huang Yongping
Published: July 2022

Sex determination is an important and traditional biological process. In Lepidoptera, Masculinizer (Masc) and doublesex (dsx) are the essential genes for sex determination and play critical roles in sexual differentiation and development. The functions of Masc and dsx have been characterized in several model insect species. However, the molecular mechanism and sex determination functions of Masc and dsx in Ostrinia furnacalis, an agricultural pest, are still unknown. Here, we successfully used the CRISPR/Cas9 genome editing system to knock out OfMasc and Ofdsx. Mutation of OfMasc induced male external genital defects and sterility. Disruptions of the Ofdsx common region caused sex-specific defects in the external genitals and adult sterility. In addition, we found that OfMasc and Ofdsx can regulate the pigmentation genes that control wing pigmentation patterns. These results demonstrate that OfMasc and Ofdsx play key roles in the sex determination of O. furnacalis, and suggest novel genetic control approaches for the management of pests, including O. furnacalis.
Thermoelectric Properties of Si-Doped In2Se3 Polycrystalline Alloys
Authors: Park Okmin , Lee Se Woong , Kim Sang-il
Published: July 2022

Post-metal chalcogenides, including InSe, In2Se3, and In4Se3, have attracted considerable attention as potential thermoelectric materials because of their intrinsically low thermal conductivity, which is attributed to their layered structure with weak van der Waals bonds. In this study, we examined the electrical and thermoelectric properties of Si-doped In2Se3 (In2−xSixSe3, x = 0, 0.005, 0.01, 0.015, and 0.02) polycrystalline samples. Hexagonal α(2H)-In2Se3 phase was synthesized without any impurity, and gradual changes in the lattice parameters were observed with Si doping. Drastic changes were observed for the measured electrical and thermal transport properties at 450–500 K, due to the phase transition from α to β at 473 K. The highest power factors were achieved by the sample with x = 0.015 for both α and β phases, exhibiting the values of 0.137 and 0.0884 mW/mK2 at 450 and 750 K, respectively. The total thermal conductivities of the α phase samples decreased gradually with increasing Si doping content, which is attributed to the point defect phonon scattering by Si doping. The total thermal conductivities of the β phase samples significantly decreased compared to those of the α phase samples. Therefore, the sample with x = 0.015 (In1.985Si0.015Se3) showed the maximum thermoelectric figure of merit values of 0.100 and 0.154 at 450 and 750 K, which are enhanced by 152 and 48% compared with those of the undoped α- and β-In2Se3 samples, respectively.
Cerebral White Matter Connectivity in Adolescent Idiopathic Scoliosis: A Diffusion Magnetic Resonance Imaging Study
Authors: Noriega-Gonzalez David C. , Crespo Jesús , Ardura Francisco , Calabia-del Campo Juan , Alberola-Lopez Carlos , de Luis-García Rodrigo , Caballero-García Alberto , Córdova Alfredo
Published: July 2022

Adolescent idiopathic scoliosis (AIS) is characterized by the radiographic presence of a frontal plane curve, with a magnitude greater than 10° (Cobb technique). Diffusion MRI can be employed to assess the cerebral white matter. The aim of this study was to analyze, by means of MRI, the presence of any alteration in the connectivity of cerebral white matter in AIS patients. In this study, 22 patients with AIS participated. The imaging protocol consisted in T1 and diffusion-weighted acquisitions. Based on the information from one of the diffusion acquisitions, a whole brain tractography was performed with the MRtrix tool. Tractography is a method to deduce the trajectory of fiber bundles through the white matter based on the diffusion MRI data. By combining cortical segmentation with tractography, a connectivity matrix of size 84 × 84 was constructed using FA (fractional anisotropy), and the number of streamlines as connectomics metrics. The results obtained support the hypothesis that alterations in cerebral white matter connectivity in patients with adolescent idiopathic scoliosis (AIS) exist. We consider that the application of diffusion MRI, together with transcranial magnetic stimulation neurophysiologically, is useful to search the etiology of AIS.
Influence of Volume-to-Surface Area Ratio on the Creep Behavior of Steel Fiber Ceramsite Concrete Beams
Authors: Li Xiu , Zhu Hongbing , Fu Zhenghao , Liu Peng , Xia Changhuang
Published: July 2022

To explore the influence of the volume-to-surface area ratio (V/S) on the creep of ceramsite concrete beams, the creep performance of ceramsite concrete beams with different V/S was studied through a long-term deformation observation test, theoretical derivation analysis and finite element modeling. First, by observing the creep deflection of ceramsite concrete beams with five different V/Ss for 180 days, the relationship between creep deflection and loading time as well as the influence of V/S on creep deflection were obtained. Then, referring to the ACI209 and ACI435 creep coefficient calculation formula, the creep theory of ceramsite concrete beams involving V/S was established. Finally, the numerical model was built according to the test parameters. The results showed that the growth rate of the creep of ceramsite concrete beams increased rapidly in the early stage, but gradually slowed down with the passage of time and tended to be stable after 120 days of loading. The V/S had a significant impact on the creep of ceramsite concrete beams. In the first 7 days, the creep growth rate of each beam was approximately the same. Thereafter, the higher the V/S was, the lower the creep became. After 28 days, the creep of ceramsite concrete beams with varied V/Ss showed sharp differences. After the V/S exceeded 30, the increasing V/S could effectively reduce the creep value and the creep growth rate under a long-term load. The calculated results were in good agreement with the measured values, which fully reflected its creep variation. The finite element simulation further verified the influence of V/S on the creep of ceramsite concrete beams and the reliability of the creep calculation formula.
Study on Deuterium Permeation Behavior of Palladium Films Prepared by Magnetron Sputtering Method
Authors: Hong Zhihao , Wang Long , Feng Yongjin , Gong Baoping , Yang Jijun , Wang Xiaoyu
Published: July 2022

Pre-depositing a Pd film is crucial for accurately acquiring the hydrogen permeability of metal materials, as it permits the production of ultra-pure hydrogen. However, the microstructure of Pd film and its effect on the hydrogen isotope permeation behavior of substrate materials have been neglected. In this study, Pd films were deposited on China Low-activation Ferritic (CLF−1) steel by magnetron sputtering. The effect of sputtering pressure on the microstructure and deuterium permeation behavior of Pd films at temperatures of 550−650 °C is presented. SEM results demonstrated that the films had a columnar crystal structure with a thickness of 0.6 ± 0.2 μm. The gas-driven permeation results revealed that the deuterium ion current intensity of the coated CLF−1 sample was at least three times lower than that of uncoated CLF−1 steel, which was influenced by the combined effect of oxygen and surface cracks. Oxygen could not be excluded from the films at a sputtering pressure of 10−3 Pa order of magnitude. It was also found that the films cracked during deuterium permeation experiments, which affected the deuterium permeation behavior. Films with large surface coverage and small grain sizes exhibited better cracking resistance. Our study provides promising insights into the hydrogen permeability of Pd films.
Magnetic Structure and Strain State in Fe/V Superlattices Studied by 57Fe+ Emission and Conversion Electron Mössbauer Spectroscopy
Authors: Mølholt Torben E. , Ólafsson Sveinn , Gunnlaugsson Haraldur P. , Qi Bingcui , Johnston Karl , Mantovan Roberto , Masenda Hilary , Bharuth-Ram Krish , Gíslason Hafliði P , Langouche Guido , Naidoo Deena
Published: July 2022

The magnetic properties of the Fe/V superlattices were studied by conventional Conversion Electron Mössbauer Spectroscopy (CEMS) and online 57Fe+ emission Mössbauer Spectroscopy (eMS) at room temperature (RT) at ISOLDE/CERN. The unique depth-enhanced sensitivity and ultradiluted regime of the probe atoms adopted in this eMS facility enabled the investigation of the magnetic structures and the strain state in the superlattice layers and at the interfaces. The magnetic spectra of the superlattices were found to depend on both the local lattice environment and the strain state of the Fe-lattices. The magnetic polarisation in the V-layers or at the interfaces was not detected at RT. Spectral broadening was evident in the single line component of the eMS due to Fe ions substituted at V-lattice sites in the V-layers of the superlattice, attributable to the lattice strain in the V-layers. Our study demonstrate that with the online eMS technique the effects of the strain state of the superlattice on the magnetic properties of the Fe-layer in the Fe/V multilayer structures can be detected.
Mechanical Behavior and Microstructure of Graphene Oxide Electrodeposited Carbon Fiber Reinforced Cement-Based Materials
Authors: Wang Siyue , Wang Xuezhi , He Jingjing , Xin Ming
Published: July 2022

In this study, graphene oxide (GO) was prepared by an improved Hummers’ method, and the graphene oxide–carbon fiber (GO-CF) hybrid fibers were prepared by electrophoretic deposition (EPD) with the above GO. The microstructure and mechanical properties of GO, CF and GO-CF cement matrix composites were studied by X-ray diffraction (XRD), SEM and mechanical tests. X-ray diffraction (XRD) and SEM results showed that the surface modification of CF with GO could effectively improve the dispersion of CF in the cement matrix, the template action of GO providing nucleation sites for cement hydration, which significantly enhanced the interface bond between CF and the cement matrix. The mechanical properties test results showed that the early compressive strength and flexural strength of cement matrix composites were significantly improved by GO. Adding CF into the cement matrix significantly improved the flexural strength, although the compressive strength was not improved, even exhibiting a downward trend when the CF content exceeded 0.5%. The flexural and compressive strength of GO-CF cement matrix composites were clearly improved, its 7 d flexural strength and compressive strength increased by 30.89% and 17.56%, respectively, and its 28 d flexural strength and compressive strength increased by 38.37% and 14.32%, respectively. The research results indicate that a new method was provided which used GO as a dispersant and surface modifier to improve the dispersion of chopped CF in a cement matrix, and the interaction between CF and the cement matrix interface could also be applied to the functional aspects of cement matrix composites.
Are Afrotropical Protected Areas Effective in Increasing Waterbird Richness and Diversity? A Case Study from South Sudan (East Africa)
Authors: Demaya Gift Simon , Gordon Shazali Abdallah , Lado Thomas Francis , Luiselli Luca , Battisti Corrado
Published: July 2022

In many tropical areas of high conservation concern there is still no evidence on the effectiveness of protected areas in protecting specific components of biodiversity. Here, to assess the management effectiveness of protected areas, we carried out a field sampling design for collecting data on waterbird communities within the Nibule National Park (South Sudan), a poorly-known hot-spot of biodiversity, and in the surrounding buffer zone. All the metrics of richness (absolute species richness, Margalef index, Chao-1) and diversity were significantly higher for bird communities inhabiting the national park, when compared to the buffer zone. Evenness was predictably lower in the national park when compared to the buffer zone, probably due to the large numbers of rare species that were observed in the park’s richer communities, thus increasing the differences in relative frequencies between species. The diversity profiles highlighted this pattern, with more sloping curves in the park sites, evidencing a role of protected area management in positively affecting the bird community structure. Our data provide the first evidence for a poorly-known area of high conservation concern on the effective role played by a National Park in maintaining high values of richness and diversity, at least for wetland-related birds.
Neuroendocrine Carcinoma at the Sphenoid Sinus Misdiagnosed as an Olfactory Neuroblastoma and Resected Using High-Flow Bypass
Authors: Takabayashi Kosuke , Shindo Takafumi , Kikuchi Tomoki , Takizawa Katsumi
Published: July 2022

In the diagnosis of olfactory neuroblastoma (ONB), the presence of S-100–positive sustentacular cells surrounding the tumor is important; however, these are also present in normal nasal sinus epithelium. Although ONB often has a different final diagnosis, complete resection of the tumor has a good prognosis and minimally affects the patient’s treatment plan. When the tumor extends around the internal carotid artery (ICA), complete resection is difficult due to the high risk of vascular injury; revascularization using high-flow bypass can avoid this complication. In the present case, the tumor was located in the left sphenoid sinus and extended around the ICA. Preoperative biopsy tissue was positive for neuroendocrine markers and slightly positive for S-100 protein, leading to a diagnosis of ectopic ONB. High-flow bypass revascularization with trapping of the ICA allowed complete tumor resection. The postoperative histopathological diagnosis was neuroendocrine carcinoma, showing no S-100 protein-positive cells. There was no sign of recurrence at 30 months after surgery without additional treatment. This case demonstrates that the presence of S-100 protein-positive cells in ONB may be misleading. Although misdiagnosis of ectopic ONB should be anticipated, a complete resection of the tumor is an effective treatment strategy.
Lipoprofiling Assessed by NMR Spectroscopy in Patients with Acute Coronary Syndromes: Is There a Need for Fasting Prior to Sampling?
Authors: Stănciulescu Laura-Adina , Scafa Alexandru , Duduianu Cătălin , Stan Raluca , Nicolescu Alina , Deleanu Calin , Dorobanțu Maria
Published: July 2022

Most patients presenting in an emergency unit with acute coronary syndromes (ACS) (which include non-ST-elevation myocardial infarction (NSTEMI), ST-elevation MI (STEMI), and unstable angina) usually meet at least two cardiovascular risk factors, such as dyslipidemia, arterial hypertension, diabetes mellitus type 2, obesity, history of or current smoking, etc. Most ACS patients suffer from a type of dyslipidemia, and in addition to this there are ACS patients rushed into the emergency units for which the feeding status is unknown. Thus, we set out to evaluate the effect of fasting on 16 blood metabolite concentrations and 114 lipoprotein parameters on one control group and a group of statin-treated ACS patients hospitalized in a cardiovascular emergency unit, using Nuclear Magnetic Resonance (NMR) spectroscopy. The results indicated trends (in terms of number of cases, but not necessarily in terms of the magnitude of the effect) for as many as four metabolites and 48 lipoproteins. The effect was defined as a trend for results showing over 70% of the cases from either one or both groups that experienced parameter changes in the same direction (i.e., either increased or decreased). In terms of magnitude, the effect is rather low, leading to the overall conclusion that in cardiovascular (CV) emergency units, the blood samples analyzed in any feeding status would provide close results and very valuable information regarding prognosis and for fast decisions on patient’s proper management.
Association between Fibrinogen-to-Albumin Ratio and Prognosis of Hospitalized Patients with COVID-19: A Systematic Review and Meta-Analysis
Authors: Hung Kuo-Chuan , Huang Yen-Ta , Chang Ying-Jen , Yu Chia-Hung , Wang Li-Kai , Wu Chung-Yi , Liu Ping-Hsin , Chiu Sheng-Fu , Sun Cheuk-Kwan
Published: July 2022

Although the fibrinogen-to-albumin ratio (F/R ratio) has been used as an inflammation marker to predict clinical outcomes in patients with cardiovascular diseases, its association with the prognosis of patients with coronavirus disease 2019 (COVID-19) remains unclear. Electronic databases including EMBASE, MEDLINE, Google Scholar, and Cochrane Library were searched from inception to 20 June 2022. The associations of F/R ratio with poor prognosis (defined as the occurrence of mortality or severe disease) were investigated in patients with COVID-19. A total of 10 studies (seven from Turkey, two from China, one from Croatia) involving 3675 patients published between 2020 and 2022 were eligible for quantitative syntheses. Merged results revealed a higher F/R ratio in the poor prognosis group (standardized mean difference: 0.529, p < 0.001, I2 = 84.8%, eight studies) than that in the good prognosis group. In addition, a high F/R ratio was associated with an increased risk of poor prognosis (odds ratio: 2.684, I2 = 59.5%, five studies). Pooled analysis showed a sensitivity of 0.75, specificity of 0.66, and area under curve of 0.77 for poor prognosis prediction. In conclusion, this meta-analysis revealed a positive correlation between F/A ratio and poor prognostic outcomes of COVID-19. Because of the limited number of studies included, further investigations are warranted to support our findings.
A Combined Approach for Accurate and Accelerated Teeth Detection on Cone Beam CT Images
Authors: Du Mingjun , Wu Xueying , Ye Ye , Fang Shuobo , Zhang Hengwei , Chen Ming
Published: July 2022

Teeth detection and tooth segmentation are essential for processing Cone Beam Computed Tomography (CBCT) images. The accuracy decides the credibility of the subsequent applications, such as diagnosis, treatment plans in clinical practice or other research that is dependent on automatic dental identification. The main problems are complex noises and metal artefacts which would affect the accuracy of teeth detection and segmentation with traditional algorithms. In this study, we proposed a teeth-detection method to avoid the problems above and to accelerate the operation speed. In our method, (1) a Convolutional Neural Network (CNN) was employed to classify layer classes; (2) images were chosen to perform Region of Interest (ROI) cropping; (3) in ROI regions, we used a YOLO v3 and multi-level combined teeth detection method to locate each tooth bounding box; (4) we obtained tooth bounding boxes on all layers. We compared our method with a Faster R-CNN method which was commonly used in previous studies. The training and prediction time were shortened by 80% and 62% in our method, respectively. The Object Inclusion Ratio (OIR) metric of our method was 96.27%, while for the Faster R-CNN method, it was 91.40%. When testing images with severe noise or with different missing teeth, our method promises a stable result. In conclusion, our method of teeth detection on dental CBCT is practical and reliable for its high prediction speed and robust detection.
Link between Insulin Resistance and Obesity—From Diagnosis to Treatment
Authors: Gołacki Jakub , Matuszek Małgorzata , Matyjaszek-Matuszek Beata
Published: July 2022

Insulin resistance (IR) has become a common health issue in medical practice. There are no detailed data on IR prevalence, but it is an increasing problem due to its close association with obesity. However, IR is not considered as a separate nosological entity and the diagnostic criteria are not well defined, which leads to overdiagnosis of IR and an inappropriate approach. This review aims to summarize the available literature on IR pathophysiology, its relationship with obesity, as well as diagnostic methods, clinical presentation and treatment. Excessive energy intake results in cell overload that triggers mechanisms to protect cells from further energy accumulation by reducing insulin sensitivity. Additionally, hypertrophied adipocytes and macrophage infiltration causes local inflammation that may result in general inflammation that induces IR. The clinical picture varies from skin lesions (e.g., acanthosis nigricans) to metabolic disorders such as diabetes mellitus or metabolic-associated fatty liver disease. There are numerous IR laboratory markers with varying sensitivities and specificities. Nutrition changes and regular physical activity are crucial for IR management because a reduction in adipose tissue may reverse the inflammatory state and consequently reduce the severity of insulin resistance. In cases of obesity, anti-obesity medications can be used.
Unoccupied Aerial Systems: A Review of Regulatory and Legislative Frameworks in the Caribbean
Authors: Ramsewak Deanesh , Mohammed Naimah Salimah , Sookram Noel
Published: July 2022

Unoccupied aerial systems (UAS) have become pervasive for many small-scale and large-scale aerial operations around the world. Their implementation in small island states like those of the Caribbean is particularly useful because they are relatively cheap and versatile. Despite being used for more than a decade in this part of the world, however, many territories in this tropical region still do not have adequate regulatory and/or legislative frameworks to support UAS operations. UAS applications are varied in the Caribbean, ranging from recreational use and coral reef monitoring to public utilities and national security support. In this paper, we present the first collective assessment of existing UAS regulatory and legislative frameworks in the Caribbean region. Data on four factors that are critical to UAS operations was collected and analyzed for the fifteen full-member Caribbean Community (CARICOM) countries. Across the duration of this study, some of the countries assessed had no existing frameworks in place, while one had completely banned UAS operations within its jurisdiction. Others, including Guyana, Trinidad and Tobago, and Jamaica, had comprehensive frameworks that were continuously being updated. The outcome of a more in-depth analysis revealed that the UAS legislative framework for Guyana appeared to be the most robust amongst all CARICOM territories. Finally, some of the challenges of proper UAS regulation observed in the region are presented.
Association between Suicide Rate and Human Development Index, Income, and the Political System in 46 Muslim-Majority Countries: An Ecological Study
Authors: Arafat S. M. Yasir , Marthoenis Marthoenis , Khan Murad M. , Rezaeian Mohsen
Published: July 2022

Very little has been researched assessing the relationship between the suicide rate and the ecological perspectives of the country, especially in the Muslim majority countries. We aimed to determine the association between suicide rate and the ecological parameters of 46 Muslim majority countries. We extracted the Muslim majority countries and their suicide rate, income distribution, distribution of the WHO region and continents, and Human Development Index (HDI). We assessed the correlation of the proportion of Muslim populations, the total population of the countries, number of suicides, continent, income group, political system, and HDI score with the suicide rate. The median suicide rate was 5.45 (IQR = 4.8); 2.9 (IQR = 4) in females and 7.45 (IQR = 8.2) in males per 100,000 population. The males had a significantly higher rate and the highest suicide rate was found in Africa. There are inverse associations between the total suicide rate, the rate in males, and females with HDI, and the income of the country. Furthermore, the suicide rate was significantly higher in countries with democratic systems compared to non-democratic countries. The findings suggest that ecological parameters may have an etiological role on suicides in Muslim countries where HDI and income are inversely associated with suicide rates.
Secure PD-NOMA with Multi-User Cooperation and User Clustering in Both Uplink and Downlink PD-NOMA
Authors: Mahmood Asif , Marey Mohamed , Nasralla Moustafa M. , Esmail Maged A. , Mostafa Hala
Published: July 2022

The power domain non-orthogonal multiple access (PD-NOMA) scheme has gained tremendous interest with the multiple access behavior for fifth-generation (5G) wireless communication. Although the overall performance is improved through accurate power distribution among users’ signals, it depends on the user clustering strategy. Moreover, the PD-NOMA communication is not completely secured due to its broadcast nature, which is still a major problem. This paper presents a novel low-complexity short code-based technique utilized by the registered users and the 5G base station (gNodeB) for communication. By doing so, the PD-NOMA scheme is made secure from unregistered users or eavesdroppers. We proposed a three-step user clustering strategy that selects the best cluster among all the possible clusters to improve the overall performance. The proposed clustering strategy achieves a low outage probability in PD-NOMA systems. Moreover, it uses a multi-user decode and forward cooperative relaying scheme with PD-NOMA (Cop-PD-NOMA) to increase the coverage range of the gNodeB. In the multi-user Cop-PD-NOMA, the strong users (near users) are used as relay stations to aid the weak users (far users) by the decode and forward (D&F) technique. The proposed work provides a secure PD-NOMA network and the most effective user clustering approach during validation. The bit-error-rate (BER) comparisons demonstrate that multi-user cooperation outperforms single-user cooperation in Cop-PD-NOMA communication.