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In this paper, an evaluation of the multiwavelet basis’ capability to represent the ECG signal sparsely was performed. The paper includes the mathematical formulation of sparsity, a brief introduction to the multiwavelet transform, as well as details about the simulation setup used for evaluation. Throughout the paper, various multiwavelets were investigated. The reported results show that the BAT and DB multiwavelets performed well, thus they could be used in the ECG signal sparsification. The investigation also focused on the ECG signals displaying deformations associated with illnesses. Preliminary results suggest that multiwavelets may prove beneficial for diverse processing of ECG signals.

Hydrogenated nanodiamonds (NDs) get increasing attention as promising nanomaterial in biology as well as optoelectronics. This study shows how the ND synthesis process and ND size are reflected in their different colloidal/hydration and electronic properties. We employ three different ND types: detonation ND (DND), top-down high-pressure high-temperature ND (TD_HPHT ND) prepared by milling of HPHT monocrystals, and bottom-up high-pressure high-temperature ND (BU_HPHT ND) prepared by HPHT synthesis from chloroadamantane. Zeta potential measurements and Fourier transform infrared spectroscopy analysis (FTIR) reveal the best colloidal stability in neutral to basic pH and the strongest affinity to water for DND. Electrical and FTIR measurements connected with an annealing treatment show a steep increase of electrical conductivity in BU_HPHT ND above 2 nm and reveal different contribution of transfer doping in BU_HPHT ND and TD_HPHT ND despite similar conductivity values (≈ 10−5 S.cm−1). We also confirm the correlation of the ND conductivity with IR transmission at the phonon frequency of the diamond (1330 cm−1). Neutron irradiation of a TD_HPHT ND corroborates the crucial role of structural defects in the above colloidal and electronic properties of hydrogenated nanodiamonds.

We investigated the use of boron-doped diamond (BDD) with different surface morphologies for the enhanced detection of nine different peptides by matrix-assisted laser desorption/ionisation mass spectrometry (MALDI-MS). For the first time, we compared three different nanostructured BDD film morphologies (Continuous, Nanograss, and Nanotips) with differently terminated surfaces (-H, -O, and -F) to commercially available Ground Steel plates. All these surfaces were evaluated for their effectiveness in detecting the nine different peptides by MALDI-MS. Our results demonstrated that certain nanostructured BDD surfaces exhibited superior performance for the detection of especially hydrophobic peptides (e.g., bradykinin 1–7, substance P, and the renin substrate), with a limit of detection of down to 2.3 pM. Further investigation showed that hydrophobic peptides (e.g., bradykinin 1–7, substance P, and the renin substrate) were effectively detected on hydrogen-terminated BDD surfaces. On the other hand, the highly acidic negatively charged peptide adrenocorticotropic hormone fragment 18–39 was effectively identified on oxygen-/fluorine-terminated BDD surfaces. Furthermore, BDD surfaces reduced sodium adduct contamination significantly.

This article focuses on the eco-friendly (green) synthesis of silver nanoparticles (AgNPs) and their incorporation into a polymer matrix. For AgNPs synthesis, Lavandula angustifolia (lavender) leaf extract was used as a reducing and stabilizing agent, and as a silver precursor, AgNO3 solution with different concentrations of silver (50, 100, 250, and 500 mg/L) was used. Prepared AgNPs colloids were characterized using UV–vis spectrophotometry, transmission electron microscopy (TEM), and X-ray diffraction (XRD). The spherical morphology of AgNPs with an average size of 20 nm was confirmed across all samples. Further, the antimicrobial properties of the AgNPs were evaluated using the disk diffusion method on algae (Chlorella kessleri) and the well diffusion method on bacteria (Staphylococcus chromogenes, Staphylococcus aureus, and Streptococcus uberis), along with root growth inhibition tests on white mustard (Sinapis alba). Polymer composite (PVA–AgNPs) was prepared by incorporation of AgNPs into the polymer matrix. Subsequently, non-woven textiles and thin foils were prepared. The distribution of AgNPs within the nanocomposites was observed by scanning electron microscopy (SEM). Antibacterial properties of PVA–AgNPs composites were analyzed on bacteria Streptococcus uberis. It was found that not only AgNPs showed good antimicrobial properties, but toxic properties were also transferred to the PVA–AgNPs nanocomposite.

Cardiovascular disease is the most common cause of death worldwide. In this regard, there is a need to find and implement effective methods for the prevention and treatment of such diseases. Lifestyle modification is an important component of a complex of preventive and therapeutic measures, including nutrition optimization, increased physical activity, and breaking bad habits. Currently, an actively developing area is the use of biologically active additives to food, in order to replenish the missing nutrients in the diet and maintain health. In the course of the present review, an analysis was made of randomized clinical trials performed over the past 5 years. The studies investigated both the short-term effects of taking omega-3 polyunsaturated fatty acids (effect on the blood lipid spectrum, blood pressure levels) and longterm results (development of myocardial infarction, stroke, cardiovascular mortality). This supplement has demonstrated a positive effect on immediate outcomes, namely the reduction of total cholesterol, low-density lipoprotein, triglycerides (lipid-lowering effect). However, there was no significant effect on long-term results. It also provides information on studies that have examined the cardioprotective effects of supplements such as resveratrol, red yeast rice, L-arginine, and curcumin. An analysis of publications has shown that these supplements have the potential to reduce the risk of development and progression of cardiovascular diseases due to possible hypolipidemic, endothelial protective, and antihypertensive effects. Nutraceutical support can be an effective addition to the basic treatment and help reduce morbidity and mortality due to cardiovascular disease.

The modification of nanodiamond (ND) surfaces has significant applications in sensing devices, drug delivery, bioimaging, and tissue engineering. Precise control of the diamond phase composition and bond configurations during ND processing and surface finalization is crucial. In this study, we conducted a comparative analysis of the graphitization process in various types of hydrogenated NDs, considering differences in ND size and quality. We prepared three types of hydrogenated NDs: high-pressure high-temperature NDs (HPHT ND-H; 0–30 nm), conventional detonation nanodiamonds (DND-H; ~5 nm), and size- and nitrogen-reduced hydrogenated nanodiamonds (snr-DND-H; 2–3 nm). The samples underwent annealing in an ultra-high vacuum and sputtering by Ar cluster ion beam (ArCIB). Samples were investigated by in situ X-ray photoelectron spectroscopy (XPS), in situ ultraviolet photoelectron spectroscopy (UPS), and Raman spectroscopy (RS). Our investigation revealed that the graphitization temperature of NDs ranges from 600 °C to 700 °C and depends on the size and crystallinity of the NDs. Smaller DND particles with a high density of defects exhibit a lower graphitization temperature. We revealed a constant energy difference of 271.3 eV between the sp-peak in the valence band spectra (at around 13.7 eV) and the sp3 component in the C 1s core level spectra (at 285.0 eV). The identification of this energy difference helps in calibrating charge shifts and serves the unambiguous identification of the sp3 bond contribution in the C 1s spectra obtained from ND samples. Results were validated through reference measurements on hydrogenated single crystal C(111)-H and highly-ordered pyrolytic graphite (HOPG).

Alumina (Al2O3) ceramics are interesting for low-weight and mid-high temperature applications. The addition of indium (In) and graphene nanoplatelets (GNPs) can be used to reduce the density and modify the functional properties and mechanical performance of the ceramic matrix. GNP and In-reinforced Al2O3 matrix composites were prepared by the spark plasma sintering (SPS) technique. Monolithic Al2O3 and Al2O3 matrix composites with either 5 or 10 wt.% of In and 2 wt.% of GNPs (Al2O3-5In-2GNPs and Al2O3-10In-2GNPs) were compacted into disc-shaped samples. The microstructure was studied and characterized with light-optical microscopy (LOM) and scanning electron microscopy (SEM). Hardness was determined using the Vickers technique and tribological properties were studied by the ball-on-disk method. The coefficient of friction (COF) and specific wear rates were evaluated from tribological tests. Worn surfaces were studied by SEM and confocal microscopy. Interdiffusion transition regions were formed among individual microstructural constituents (Al2O3, In, GNPs) under high sintering temperatures, which were responsible for the balanced hardness and low porosity of the produced composites. The addition of In and graphene nanoplatelets resulted in smaller COF and wear rates indicating good improvement in the tribological behavior. The prepared Al2O3-5In-2GNP and Al2O3-10In-2GNP composites represent promising nanocomposites for self-lubricating applications.

This contribution describes the preparation, coupled with detailed characterization, of Nb2O5 nanofibers and their application in lithium–sulfur batteries for the improvement of electrochemical performance. The utilization of reactive needle-less electrospinning allowed us to obtain, in a single step, amorphous pre-ceramic composite PAN/Nb2O5 fibers, which were transformed into porous ceramic Nb2O5 nanofibers via calcination. Thermogravimetric studies defined that calcination at 600 °C results in crystalline ceramic fibers without carbon residues. The fibrous morphology and mean diameter (614 ± 100 nm) of the ceramic nanofibers were analyzed via scanning and transmission electron microscopy. A surface area of 7.472 m2/g was determined through nitrogen adsorption measurements, while a combination of X-ray diffraction and Raman spectroscopy was used to show the crystallinity and composition of the fibers after calcination—single T-phase Nb2O5. Its performance in the cathode of lithium–sulfur batteries was defined through electrochemical tests, and the obtained results were compared to a similar blank electrode. The initial discharge capacity of 0.5 C reached a value of 570 mAh∙g−1, while the reversible capacity of 406 mAh∙g−1 was retained after 200 cycles, representing a capacity retention of 71.3%. The presence of Nb2O5 nanofibers in the carbon cathode inhibits the shuttle effect through polysulphide confinement, which originates from porosity and chemical trapping.

The purpose of this teaching experiment was to examine the causal effect of relevant (compared to irrelevant) instructor self-disclosure on student affect and cognitive learning. Undergraduate students (N = 288) were randomly assigned to a 19-minute classroom lecture with an instructor who taught the same lesson but self-disclosed either relevant or irrelevant information while teaching. Results indicated that relevant instructor self-disclosure increased student affect in students' likelihood to enroll with the instructor again but did not influence students' general affect toward the instructor. Findings also revealed a direct effect of self-disclosure relevance on students' test scores; on average, students scored 8.42% higher on a short-term recall test compared to students in the irrelevant self-disclosure condition, controlling for lesson coherence. Practical implications are provided for how instructors might use relevant self-disclosures in their teaching.

The purpose of this study was to continue the trend of identifying the course offerings of National Communication Association (NCA) department members started by Wardrope (1999). A curricular profile of U.S. communication departments. "Communication Education," "48"(3), 256-258. https://doi.org/10.1080/03634529909379173 and followed by Bertelsen and Goodboy (2009). Curriculum planning: Trends in communication studies, workplace competencies, and current programs at 4-year colleges and universities. "Communication Education," "58"(2), 262-275. https://doi.org/10.1080/03634520902755458. Supported by an Advancing the Discipline grant obtained by the NCA in 2019, this third iteration identifies the Top 30 course offerings across 322 NCA Department members as of May 2020. The results indicate that over the past three decades, the most currently offered communication courses have remained relatively stable, with the interpersonal communication course remaining the most currently offered course by NCA department members, followed (in this study) by the persuasion, introductory, intercultural, public speaking, organizational, group, research methods, argumentation and debate, and theory courses. Future researchers might extend this line of research by inquiring whether these offered courses are required for the undergraduate degree in communication, a department major or area of emphasis, a department minor, or institutional graduation as well as probe the graduate courses offered by communication departments.

The purpose of this longitudinal study was to model student trajectories of instructional dissent over the course of a semester. Participants were 312 undergraduate students who completed panel surveys on their worst course of the semester at three time points: during the beginning, middle, and end of a college course. Latent growth curve modeling revealed that, on average, expressive dissent slightly decreased, rhetorical dissent remained unchanged, and vengeful dissent slightly increased each month during the semester. Above and beyond the dissent growth process, student anger and hopelessness were independent and contemporaneous predictors of expressive and vengeful dissent at each time point.

Abstract The present study investigates the effect of an oxidized nanocrystalline diamond (O-NCD) coating functionalized with bone morphogenetic protein 7 (BMP-7) on human osteoblast maturation and extracellular matrix mineralization in vitro and on new bone formation in vivo. The chemical structure and the morphology of the NCD coating and the adhesion, thickness and morphology of the superimposed BMP-7 layer have also been assessed. The material analysis proved synthesis of a conformal diamond coating with a fine nanostructured morphology on the Ti6Al4V samples. The homogeneous nanostructured layer of BMP-7 on the NCD coating created by a physisorption method was confirmed by AFM. The osteogenic maturation of hFOB 1.19 cells in vitro was only slightly enhanced by the O-NCD coating alone without any increase in the mineralization of the matrix. Functionalization of the coating with BMP-7 resulted in more pronounced cell osteogenic maturation and increased extracellular matrix mineralization. Similar results were obtained in vivo from micro-CT and histological analyses of rabbit distal femurs with screws implanted for 4 or 12 weeks. While the O-NCD-coated implants alone promoted greater thickness of newly-formed bone in direct contact with the implant surface than the bare material, a further increase was induced by BMP-7. It can be therefore concluded that O-NCD coating functionalized with BMP-7 is a promising surface modification of metallic bone implants in order to improve their osseointegration.

Background: Adverse local tissue reaction (ALTR) is a recognized complication of total hip arthroplasty (THA) with metal-on-polyethylene (MoP) bearing surface implants. Specific models of THA implants have been identified as having a higher incidence of ALTR. The purpose of this study is to determine if serum metal levels, patient symptoms, implant factors, and imaging findings can be predictive of ALTR within this high-risk population. Methods: We retrospectively reviewed an observational cohort of 474 patients who underwent MoP THA and were at increased risk of having ALTR. Patients were stratified based on the presence or absence of ALTR. Patient symptoms, serum metal ions, implant head offset, and imaging findings were compared. Results: Patients with ALTR were more likely to be symptomatic (52.9% vs 9.9%, P < .0001). The presence of ALTR was associated with significantly higher serum cobalt and chromium levels (6.2 ppb vs 3.6 ppb, P < .0001; 2.3 ppb vs 1.2 ppb, P < .0001). Head offsets greater than 4 mm were associated with a higher prevalence of ALTR (53% vs 38%, P = .05). On metal artifact reduction sequence magnetic resonance imaging, patients with ALTR had larger effusions (4.7 cm vs 2.1 cm, P < .001) and a higher incidence of trochanteric bursitis (47% vs 16%, P < .001). Conclusions: In high-risk MoP implants, serum cobalt and chromium levels are elevated, even in patients without ALTR. A larger femoral head offset is a risk factor for the development of ALTR. Our study suggests that patients presenting with painful THA and elevated metal ions require risk stratification based on patient symptoms, metal artifact reduction sequence magnetic resonance imaging findings, and implant factors.

The aim of this article is identification of the subjective reception of external stimuli during wheelchair driving by analyses of vibration signals obtained from measurements. The identification concerns the impact of vibrations generated during crossing various types of pavements on the discomfort feelings of the selected human body parts (mainly the spine). The identification used the measurements of the whole body vibrations received by the user of the wheelchair. The research focuses mainly on the analysis in the frequency ranges corresponding to the vibration resonance of the spine. It is because respondents of the conducted surveys selected the spine as one of the most sensitive parts of the body.

Nanostructured boron-doped diamond (BDD) offers a sizeable ion-accessible area, high mechanical robustness, and high electrical conductivity, and could be a suitable electrode for high-performance electrochemical (EC) supercapacitors. Herein, two morphological BDD films, namely, boron-doped microcrystalline diamond (BMCD) and boron-doped ultra-nanocrystalline diamond (BUNCD), are employed for nanostructuring. The diamond nanopillars are fabricated via the Au mask-assisted reactive ion etching (RIE) method. The nanostructured samples of BMCD and BUNCD are termed BMCDN and BUNCDN. The Raman spectroscopy and X-ray photoelectron spectroscopy measurements of these nanostructured samples confirm the presence of sp2 in sp3-bonded carbon, which combine to offer good EC activity of sp2 and exceptional stability of sp3 carbon. These nanostructured BDD samples with enhanced surface area are utilized as electrode materials to construct an electric double-layer capacitor and pseudocapacitor. In 1 M Na2SO4 solution, the maximum specific capacitance of BMCDN is found to be 0.0852 mF cm−2, whereas, for BUNCDN the value is 0.0784 mF cm−2. The electrochemical analysis of these samples shows they exhibit superior electron transfer kinetics with 80% capacitance retention after 2000 cycles, which indicates the suitable utilization of these nanostructured samples as electrodes in EC supercapacitors. [ABSTRACT FROM AUTHOR]

We investigated the use of boron-doped diamond (BDD) with different surface morphologies for the enhanced detection of nine different peptides by matrix-assisted laser desorption/ionisation mass spectrometry (MALDI-MS). For the first time, we compared three different nanostructured BDD film morphologies (Continuous, Nanograss, and Nanotips) with differently terminated surfaces (-H, -O, and -F) to commercially available Ground Steel plates. All these surfaces were evaluated for their effectiveness in detecting the nine different peptides by MALDI-MS. Our results demonstrated that certain nanostructured BDD surfaces exhibited superior performance for the detection of especially hydrophobic peptides (e.g., bradykinin 1–7, substance P, and the renin substrate), with a limit of detection of down to 2.3 pM. Further investigation showed that hydrophobic peptides (e.g., bradykinin 1–7, substance P, and the renin substrate) were effectively detected on hydrogen-terminated BDD surfaces. On the other hand, the highly acidic negatively charged peptide adrenocorticotropic hormone fragment 18–39 was effectively identified on oxygen-/fluorine-terminated BDD surfaces. Furthermore, BDD surfaces reduced sodium adduct contamination significantly. [ABSTRACT FROM AUTHOR]

Instructors tell stories for pedagogical reasons, but not all classroom stories are necessarily relevant to students and their learning. This study examined how instructors tell stories in ways that students find relevant or irrelevant to their lives. Participants were 388 undergraduate students who responded to an open-ended survey asking them to identify either a relevant or an irrelevant instructor narrative and then report on why the narrative was relevant or irrelevant to their classroom needs, personal interests, and/or future goals. We examined their responses using qualitative content analysis. Results revealed that most students found an instructor narrative to be relevant when it discussed perseverance through personal struggles and decision-making in college because it related to the students' own current difficulties. Many students perceived a narrative to be irrelevant when it mentioned a marital partner and/or children because students felt these stories had little to do with the course content. These results provide preliminary evidence for the types of stories instructors might share (or avoid) to ensure that students find classroom narratives pertinent to their lives.

We conducted this study to create a measure of instructional narratives and to validate the new instrument by assessing its construct validity. In particular, we created an item pool reflecting three aspects of instructor-told narratives including their course orientation, concreteness, and memorability. Students (N = 598) responded to a series of items measuring the three dimensions of instructional narratives and also their perceptions of instructor clarity, cognitive load, relevance, attention, and both emotional and cognitive interest. Results from exploratory and confirmatory factor analyses revealed that a bifactor model with a general measure of effective storytelling and three subfactors fit the data well. Moreover, the new measure of instructional narratives was related to the educational outcomes noted above in a logical manner and each dimension predicted unique associations with these. In general, our results indicated that in order to teach clearly, explaining course concepts through stories in a manner that students can easily imagine is beneficial. To capture students' attention and emotional interest, stories must be concrete and memorable. Finally, to help students learn, stories must be concrete and course-oriented.

The controlled extraction of light from diamond optical color centers is essential for their practical prospective applications as single photon sources in quantum communications and as biomedical sensors in biosensing. Photonic crystal (PhC) structures can be employed to enhance the collection efficiency from these centers by directing the extracted light towards the detector. However, PhCs must be fabricated with nanoscale precision, which is extremely challenging to achieve for current materials and nanostructuring technologies. Imperfections inherently lead to spectral mismatch of the extraction (leaky) modes with color center emission lines. Here, we demonstrate a new and simple two-step method for fabricating diamond PhC slabs with leaky modes overlapping the emission line of the silicon vacancy (SiV) centers. In the first step, the PhC structure with leaky modes blue shifted from the SiV emission line is fabricated in a nanocrystalline diamond without SiV centers. A thin layer of SiV-rich diamond is then deposited over the PhC slab so that the spectral position of the PhC leaky modes is adjusted to the emission line of the SiV centers, thereby avoiding the need for nanoscale precision of the structuring method. An intensity enhancement of the zero-phonon line of the SiV centers by a factor of nine is achieved. The color centers in the thin surface layer are beneficial for sensing applications and their properties can also be further controlled by the diamond surface chemistry. The demonstrated PhC tuning method can also be easily adapted to other optical centers and photonic structures of different types in diamond and other materials.