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The synthesis of the selenium‐based ligand L1SeSeL1 (2,2'‐diselanediylbis(N,N‐bis(pyridin‐2‐ylmethyl)ethan‐1‐amine) is described along with its reactivity with cobalt(II) salts. The cobalt(II)‐diselenide complex [Co2(L1SeSeL1)Cl4] was obtained in good yield, and its spectroscopic properties closely resemble that of its sulfur analog. Reaction of L1SeSeL1 with Co(II) thiocyanate results in the formation of the cobalt(III) compound [Co(L1Se)(NCS)2], similar to reaction of L1SSL1. The redox‐conversion reactions from the Co(II)‐diselenide compound [Co(L1SeSeL1)Cl4] using external triggers such as removal of the halide ions or the addition of the strong‐field ligand 8‐quinolinolate resulted in good yields of the Co(III)‐selenolate complexes [Co(L1Se)(MeCN)2](SbF6)2 and [Co(L1Se)(quin)]Cl. Our computational studies show that the ligand‐field splitting energy of the selenium compounds is smaller than their sulfur analogs, indicating that redox‐conversion of cobalt(II)‐diselenide to cobalt(III)‐selenolate complexes may be more arduous than that for the related sulfur compounds. [ABSTRACT FROM AUTHOR]

Hepatic tissue engineering may be an effective approach for the treatment of liver disease; however, its practical application requires hepatic cell separation technologies that do not involve cell surface modification and maintain cell activity. In this study, we developed hepatocyte cell separation materials using a thermoresponsive polymer and a polymer with high affinity to hepatocytes. A block copolymer of poly(N-p-vinylbenzyl-O-β- D -galactopyranosyl-(1→4)- D -gluconamide) (PVLA) and poly(N-isopropylacrylamide) (PNIPAAm) [PVLA-b-PNIPAAm] was prepared through two steps of atom transfer radical polymerization. On the prepared PVLA-b-PNIPAAm brush, HepG2 cells (model hepatocytes) adhered at 37 °C and detached at 20 °C, attributed to the temperature-modulated affinity between PVLA and HepG2. Cells from the immortalized human hepatic stellate cell line (TWNT-1) did not adhere to the copolymer brush, and RAW264.7 cells (mouse macrophage; model Kupffer cells) adhered to the copolymer brush, regardless of temperature. Using the difference in cell adhesion properties on the copolymer brush, temperature-modulated cell separation was successfully demonstrated. A mixture of HepG2, RAW264.7, and TWNT-1 cells was seeded on the copolymer brush at 37 °C for adherence. By reducing the temperature to 20 °C, adhered HepG2 cells were selectively recovered with a purity of approximately 85% and normal activity. In addition, induced pluripotent stem (iPS) cell-derived hepatocytes adhered on the PVLA-b-PNIPAAm brush at 37 °C and detached from the copolymer brush at 20 °C, whereas the undifferentiated iPS cells did not adhere, indicating that the prepared PVLA-b-PNIPAAm brush could be utilized to separate hepatocyte differentiated and undifferentiated cells. These results indicated that the newly developed PVLA-b-PNIPAAm brush can separate hepatic cells from contaminant cells by temperature modulation, without affecting cell activity or modifying the cell surface. Thus, the copolymer brush is expected to be a useful separation tool for cell therapy and tissue engineering using hepatocytes. [ABSTRACT FROM AUTHOR]

We have analyzed the temperature-sensitive kinetic release of dye from a temperature-sensitive porous polymer film in which poly(N-isopropylacrylamide) (PNIPAAm) was functionalized. For the temperature-sensitive kinetic release, rhodamine 6G (RhG) was used as a substitute for a drug molecule. The releasing experiment was done by using a flow UV–Vis spectrophotometer. To support the temperature-sensitive kinetic release of RhG, temperature-dependent morphology of the porous film was studied by the scanning electron microscopy (SEM) and was compared to the temperature below and above the lower critical solution temperature (LCST) (~ 32.5 °C) of the PNIPAAm. The SEM images showed a higher rugged surface morphology of the porous PNIPAAm film with the increase in temperature above the LCST. An exponential increase in the RhG release was observed at 32–34 ºC, which is higher than the LCST of PNIPAAm. This means that the change of the pore surface from the coil to the globule state supports the temperature-sensitive release by the de-swelling of PNIPAAm in addition to the release by diffusion. The RhG release over time at different temperatures was also theoretically analyzed using the Korsmeyer–Peppas kinetic model. [ABSTRACT FROM AUTHOR]

The utilization of cellulose to its full potential is constrained by its recalcitrance to dissolution resulting from the rigidity of polymeric chains, high crystallinity, high molecular weight, and extensive intra- and intermolecular hydrogen bonding network. Therefore, pretreatment of cellulose is usually considered as a step that can help facilitate its dissolution. We investigated the use of microwave oxygen plasma as a pre-treatment strategy to enhance the dissolution of cotton fibers in aqueous NaOH/Urea solution, which is considered to be a greener solvent system compared to others. Attenuated Total Reflectance Fourier Transform Infrared Spectroscopy, Scanning Electron Microscopy, and Powder X-ray Diffraction analyses revealed that plasma pretreatment of cotton cellulose leads to physicochemical changes of cotton fibers. Pretreatment of cotton cellulose with oxygen plasma for 20 and 40 min resulted in the reduction of the molecular weight of cellulose by 36% and 60% and crystallinity by 16% and 25%, respectively. This reduction in molecular weight and crystallinity led to a 34% and 68% increase in the dissolution of 1% (w/v) cotton cellulose in NaOH/Urea solvent system. Thus, treating cotton cellulose with microwave oxygen plasma alters its physicochemical properties and enhanced its dissolution. [ABSTRACT FROM AUTHOR]

The high-temperature (HT) behavior of BaAs2Zn2O8∙H2O was studied by in situ single-crystal X-ray diffraction (SCXRD) and hot stage Raman spectroscopy (HTRS) up to dehydration and the associated phase transition. During heating, the studied compound undergoes the dehydration process with the formation of BaAs2Zn2O8, which is stable up to at least 525 °C. The evolution of the fourteen main Raman bands was traced during heating. The abrupt shift of all Raman bands in the 70–1100 cm−1 spectral region was detected at 150 °C, whereas in the spectral region 3000–3600 cm−1 all the bands disappeared, which confirms the dehydration process of BaAs2Zn2O8∙H2O. The transition from BaAs2Zn2O8∙H2O to BaAs2Zn2O8 is accompanied by symmetry increasing from P21 to P21/c with the preservation of the framework topology. Depending on the research method, the temperature of the phase transition is 150 °C (HTRS) or 300 °C (HT SCXRD). According to the HT SCXRD data, in the temperature range 25–300 °C the studied compound demonstrates anisotropic thermal expansion (αmax/αmin = 9.4), which is explained by flexible crankshaft chains of TO4 (T = As, Zn) tetrahedra. Additionally, we discussed some crystal-chemical aspects of minerals with both (ZnOn) and (AsOm) polyhedra (n = 4, 5, 6; m = 3, 4) as main structural units. [ABSTRACT FROM AUTHOR]

Nitrite represents one of the most typical contaminants in aqueous species. The research was conducted to evaluate the impacts of nitrite exposure on the survival, gill morphology, hematological parameters, immune response, and meat flavor of pearl gentian grouper. The fish were exposed to 0, 5, 10, and 20 mg/L of nitrite for 96 h (note: N-0, N-5, N-10, and N-20 indicate nitrite concentrations of 0, 5, 10, and 20 mg/L, respectively). The blood, gills, and muscles were collected from fish to determine hematological parameters, immune response, oxidative stress, and meat flavor after 0, 12, 24, 36, 48, 60, 72, and 96 h of exposure. The data showed that the aspartate aminotransferase (AST), cortisol (COR), malondialdehyde (MDA), alanine aminotransferase (ALT), alkaline phosphatase (AKP), and free amino acids (FAAs) contents were significantly increased, while the glutathione (GSH), immunoglobulin M (IgM), superoxide dismutase (SOD), and lysozyme (LZM) contents were remarkably declined in the N-20 group after 72 h of exposure. In gills, exposure to the higher concentrations of nitrite resulted in the proliferation and hypertrophy of epithelial cells of gill lamellae, as well as an increase in mucous cells. In addition, all fish in the N-10 and N-20 groups died after 96 h of exposure. Our findings suggested that exposure to higher concentrations of nitrite disrupted blood physiology and oxidative stress, leading to dysfunction in the pearl gentian grouper. [ABSTRACT FROM AUTHOR]

A SiGeSn/GeSn/SiGeSn single quantum well structure featuring type-I band alignment was comprehensively characterized. Three pump lasers with different penetration depths and photon energies were used to pinpoint the optical transition characteristics of the sample. The carrier generation, redistribution, and recombination under each pumping condition were analyzed in detail. By comparing the temperature-dependent photoluminescence spectra of the GeSn quantum well with that of SiGeSn and GeSn thin film samples possessing similar Si and Sn compositions, the optical transition mechanism was clearly identified. [ABSTRACT FROM AUTHOR]

Rapid thermal anneal (RTA) at high temperatures can be employed to introduce vacancies to control oxygen precipitation (OP) behavior in Czochralski (CZ) silicon. Such excessive vacancies survive from the recombination of silicon-interstitials and vacancies (V-I recombination) during the RTA. In this work, we aim to elucidate the carbon effect on the survival of vacancies in CZ silicon during the high temperature RTA by means of gold diffusion in combination with deep-level transient spectroscopy. It is revealed that the existence of ∼1017 cm−3 carbon atoms significantly increases the amount of survival vacancies in the form of vacancy-oxygen (VOm, m ≥ 2) complexes in CZ silicon when subjected to the 1250 °C/60 s RTA. Moreover, such an increase in the number of vacancies becomes more significant with the increase in the cooling rate of RTA. The density functional theory calculations suggest that the V-I recombination is to some extent unfavorable as a carbon atom is close to the silicon-interstitial. Alternatively, it is believed that the substitutional carbon (Cs) atoms tend to trap the silicon-interstitials, thus forming Ci complexes (Cs + I → Ci) in CZ silicon during the RTA. In this context, the V-I recombination is suppressed in a manner, leading to the survival of more vacancies, thus generating more VOm complexes. Furthermore, after the 1250 °C/60 s RTA, the oxide precipitate nucleation based on the VOm complexes is more significant in carbon-rich CZ (CCZ) silicon than in the conventional CZ counterpart. Hence, when subjected to the same OP anneal consisting of the nucleation anneal at 650 or 800 °C for 4 h and the subsequent growth anneal at 1000 °C for 16 h, CCZ silicon possesses a higher density of bulk microdefects and therefore stronger internal gettering capability than CZ silicon. However, the nucleation temperature for OP should be carefully selected as 650 °C for CCZ silicon in order to form an oxide precipitate-free denuded zone. [ABSTRACT FROM AUTHOR]

Simple Summary: The red-crowned crane is an endangered bird species in the Far East Eurasian continent and Hokkaido, Japan. Individual identification has been achieved with banding and installed transmitters in only a few cranes, though individual identification is essential for various assessments of cranes on their behavioral characteristics, for example. An insertion/deletion (InDel) mutation is a mutation ranging from 1 to 50 bp and is very useful for genetic studies. If primer sets across InDels (>20 bp) can be designed, an InDel polymorphism can be determined with conventional agarose gel electrophoresis, as reported in some plant species. We found a sufficient number of InDel primer sets to be used for individual identification and analysis of population genetics of red-crowned cranes in Hokkaido. The method has additional advantages, such as convenience and low cost, without sequencing and an expensive apparatus. Red-crowned crane Grus japonensis is an endangered species in two separate populations: the mainland population in the Eurasian continent and the island population in eastern Hokkaido, Japan. We found 11 insertion/deletion (InDel) markers in the genome of the red-crowned crane and designed primer sets across these InDels that can be analyzed with conventional agarose gel electrophoresis. Sixty-six samples of whole blood and skeletal muscle obtained from red-crowned cranes, including 12 families in eastern Hokkaido from 1994 to 2021, showed different patterns in gel images of 11 InDel PCR reactions except for two pairs. The combined non-exclusion probability of the 11 markers indicates that individuals can be determined with a probability of 99.9%. In 39 non-relative chicks, the expected heterozygosity (He) was 0.316, suggesting low genetic diversity. This might not be caused by high levels of inbreeding since the average FIS was not significantly different from zero (0.095, p = 0.075). The results suggest that the 11 InDel primer sets can be used for fairly accurate individual identification as well as genetic population analyses in red-crowned cranes in the island population. [ABSTRACT FROM AUTHOR]

Alphaviruses have been engineered as expression vectors for vaccine development and gene therapy. Due to the feature of RNA self-replication, alphaviruses can provide exceptional direct cytoplasmic expression of transgenes based on the delivery of recombinant particles, naked or nanoparticle-encapsulated RNA or plasmid-based DNA replicons. Alphavirus vectors have been utilized for the expression of various antigens targeting different types of cancers, and cytotoxic and antitumor genes. The most common alphavirus vectors are based on the Semliki Forest virus, Sindbis virus and Venezuelan equine encephalitis virus, but the oncolytic M1 alphavirus has also been used. Delivery of immunostimulatory cytokine genes has been the basis for immunotherapy demonstrating efficacy in different animal tumor models for brain, breast, cervical, colon, lung, ovarian, pancreatic, prostate and skin cancers. Typically, therapeutic effects including tumor regression, tumor eradication and complete cure as well as protection against tumor challenges have been observed. Alphavirus vectors have also been subjected to clinical evaluations. For example, therapeutic responses in all cervical cancer patients treated with an alphavirus vector expressing the human papilloma virus E6 and E7 envelope proteins have been achieved. [ABSTRACT FROM AUTHOR]

Introduction: We compared the effects of chlorhexidine (CHX), sodium hypochlorite (NaOCl), and ethylene diamine tetra-acetic acid (EDTA) root canal irrigants on the pushout bond strength of Resil experimental sealer and AH26 to root dentin. Methods: In this in vitro study, 65 teeth were assigned to six groups based on the choice of final irrigant and sealer: (I) CHX and AH26, (II) CHX and Resil, (III) NaOCl and AH26, (IV) NaOCl and Resil, (V) NaOCl plus EDTA and AH26, and (VI) NaOCl plus EDTA and Resil. The teeth were decoronated and underwent chemomechanical preparation. In each group, half of the root canals were filled with AH26 and the other half with Resil plus gutta-percha by the lateral compaction technique. In the control group, the root canals were rinsed with saline and obturated without sealer. The roots were sectioned perpendicular to the longitudinal tooth axis at 3, 7, and 11 mm from the apex (apical, middle, and coronal thirds). The pushout bond strength of sealer to root dentin was measured by a universal testing machine and recorded in Newtons (N). Results: AH26 plus CHX, as well as AH26 plus NaOCl and EDTA, yielded the maximum pushout bond strength (P<0.05). The pushout bond strength in the apical third was higher than that in the middle and coronal thirds. The mean pushout bond strength of both sealers in NaOCl irrigation groups was lower than that in CHX and EDTA plus NaOCl groups. Conclusion: Resil experimental sealer had a lower pushout bond strength than AH26. [ABSTRACT FROM AUTHOR]

A novel technology has been developed to recycle steel slag as a flux for the submerged arc welding process. The chemical, mechanical, and metallurgical properties of welds produced using recycled slag have been evaluated and compared with that of fresh flux available in the market. The tensile strengths of weld metal prepared with recycled slag and fresh flux are 462.25 MPa and 471.49 MPa, which are comparable. The impact strength of welds produced using recycled slag is 83.66 J which is acceptable in accordance with AWS SFA 5.17 specifications. The welds produced were subjected to non-destructive tests such as radiography and also dye-penetration test apart from visual inspection to ascertain the soundness of welds produced. Metallurgical investigations were carried out, and a favorable microstructure containing acicular ferrite was obtained in welds deposited using recycled slag. Similar trends of microhardness survey have been observed in both the welds produced. [ABSTRACT FROM AUTHOR]

COVID-19, an acute respiratory disease caused by SARS-CoV-2, has rapidly become a pandemic. On the other hand, obesity is also reaching dramatic dimensions and it is a risk factor for morbidity and premature mortality. Obesity has been linked to a high risk of serious-associated complications to COVID-19, due to the increased risk of concomitant chronic diseases, which highlights the health public relevance of the topic. Obese subjects have a pro-inflammatory environment, which can further exacerbate COVID-19-induced inflammation and oxidative stress, explaining the increased risk of serious complications in these patients. Another factor that favors infection in obese patients is the high expression of ACE2 receptors in the adipose tissue. The negative impact of COVID-19 in obesity is also associated with a decrease in respiratory function, the concurrence of multiple comorbidities, a low-degree chronic inflammatory state, immunocompromised situation, and therefore a higher rate of hospitalization, mechanical ventilation, in-hospital complications such as pneumonia, and death. In this review, the link between obesity and COVID-19 was analyzed, exploring the potential common mechanisms in both diseases, with special attention to oxidative stress and inflammation, due to the crucial role of both pathways in the development of the disease. [ABSTRACT FROM AUTHOR]

The alleviation effect on the Schottky barrier height (SBH) (ΦB) using ultrathin titanium dioxide and hafnium dioxide dielectrics in a single layer and a bilayer stack was demonstrated. ΦB in the Pt/n-Si contact was reduced from 0.53 to −0.058, 0.3, and −0.12 eV using 3 nm TiO2, 1 nm HfO2, and high-k/high-k bilayer insertion, respectively. A maximum of 122% reduction in ΦB was obtained using bilayer dielectric insertion, which is the highest ever reduction reported so far in a Schottky diode. This was achieved by effectively passivating the semiconductor surface states by HF cleaning followed by inserting an ultrathin film produced from the novel Atomic Layer Deposition (ALD) technique. The Gaussian distribution (GD) of barrier heights all over the interface has been investigated for both Metal–Semiconductor (M–S) and Metal–Insulator–Semiconductor (M–I–S) contacts. The nonlinear behavior in a conventional Richardson plot was observed with lower values of the Richardson constant (A*). We have reported the surface inhomogeneity in both M–S and M–I–S contacts through temperature dependency of diode characteristics. The standard deviation (σ) as evidence for the Gaussian distribution of barrier heights was determined using the ln(Is/T2) vs q/2kT plot. The results were validated by a modified Richardson plot where the values of A* obtained were found to be in close agreement with the known values. As the ALD technique is known for conformity and uniformity of thin films, the dielectric insertion has proved effective in mitigating the SBH. However, the inhomogeneity in both M–S and M–I–S points to the role of dipole formation at the interface. [ABSTRACT FROM AUTHOR]

Recent research has examined the possibility of recovering energy from mechanical vibration induced by a vehicle shock absorber using piezoelectric and electromagnetic transducers. In terms of automotive applications, piezoelectric vibration energy harvesting shows promise for recapturing some (even if small) amounts of vehicle vibration energy, which would otherwise be wasted through the vehicle dampers. Functional materials, such as piezoelectric materials, are capable of converting mechanical energy into useful electrical energy and vice versa. In this paper, an innovative rotational piezoelectric vibration-energy-harvesting device is presented that employs a magnetic coupling mechanism and provides robust performance over a range of frequencies. The piezoelectric energy harvester is driven by a unidirectional suspension system. An experimental investigation was carried out to study the performance of the manufactured prototype. We observed no damage to the prototype after operating continuously at a vibration amplitude of 5 mm at a frequency of 2.5 Hz for over 10,000 cycles. In addition, the presented regenerative suspension system is capable of producing high and relatively steady open-circuit voltages, irrespective of excitation frequencies. The results demonstrate that regenerative shock absorber is robust and has a broad frequency range. [ABSTRACT FROM AUTHOR]

In this study, the purpose was to investigate the histopathological, genotoxic effect, oxidative stress and cell death due to Metronidazole (MTZ), which is a 5-nitroimidazole compound, used widely for the treatment of anaerobic organism infections in fish and humans on gill and liver tissues of Oncorhynchus mykiss. Trout fishes were exposed to 5, 10, and 20 mg/L of MTZ in the aquariums for 2, 4 and 8 days. Staining technics namely H&E, NOS immunohistochemistry, and TUNEL were performed to determine histopathological changes, oxidative damage and apoptosis. Additionally, smear preparations were also prepared from gill blood for genotoxic evaluations. The organ damage started in the 2nd day with 5 mg/L MTZ application and effects increased per duration and dose-dependent manner. It was observed that the gills had the primary and secondary lamellae lengths, with formation of clavate lamellae, fusion in secondary lamellae, separation of epithelium and aneurysm. Regional necrosis, vacuolization of hepatocytes, pycnotic nucleus, enlarged sinusoids were also determined in the liver. NOS immunoreactivity increased with the inducible immunoreactivity (iNOS) that was more prominent when compared to the endothelial immunoreactivity (eNOS). Apoptotic immunoreactivity was higher in the 10 mg 8th day experimental group at liver and gills, and was lower 20 mg 8th day experimental group. When the gills and liver compared with each other, in all doses, immunoreactivity was lower in gills, compared with liver. Genotoxic examinations showed that both number of micro nucleated erythrocytes and nuclei abnormalities were higher in MTZ-treated groups. [ABSTRACT FROM AUTHOR]

Purpose: Suspension is a significantly important component for automotive and railway vehicles. Regenerative hydraulic-electric shock absorbers (RHSA) have been proposed for the purpose of attenuating vibration of vehicle suspension, and also recover kinetic energy originated from vehicle vibration that is conventionally dissipated by hydraulic dampers. To advance the technology, the paper aims to present an RHSA system for heavy-duty and railway vehicles and create a dynamic modelling to discuss on the development process of RHSA model. Design/methodology/approach: First, the development of RHSA dynamic model can be resolved into three stage models (an ideal one, a second one with an added accumulator and a third one that considers both accumulator and system losses) to comprehensively evaluate the RHSA's characterisation. Second, a prototype is fabricated for testing and the results meet desired agreements between simulation and measurement. Finally, the study of key parameters is carried out to investigate the influences of hydraulic-cylinder size, hydraulic-motor displacement and accumulator pre-charged pressure on the RHSA system. Findings: The findings of sensitivity analysis indicate that the component design can satisfy the damping characteristics and power performance required for heavy-duty vehicle, freight wagon and typical passenger train. The results also show that reducing the losses is highly beneficial for saving suspension energy, improving system reliability and increasing power-conversion efficiency. Originality/value: The paper presents a more detailed method for the development and analysis of a RHSA. Compared with the typical shock absorbers, RHSA can also recover the vibration energy dissipated by suspension. [ABSTRACT FROM AUTHOR]

We have fabricated poly(ε-caprolactone) (PCL) films with flat and honeycomb-patterned (HCP) structures to coat polyaniline (PANI) on the film surface. In addition, the effect of chemical modification of PANI by sulfuric acid (H2SO4) was also studied for antibacterial activity. The flat and HCP PCL films were obtained by simple evaporation of the solvent and via the breath figure (BF) method, respectively. The morphology and chemical composition of PANI coated on the film surface were evaluated by scanning electron microscopy (SEM) and X-ray spectroscopy (EDX). Fourier transform infrared spectroscopy (FT-IR) and thermogravimetric analyses (TGA) were obtained to identify the PANI coating. The wettability and conductivity of the films were also measured. Applicational aspects were evaluated by assessing antibacterial and antibiofilm activity against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). The EDX, TGA, and FT-IR findings indicated chemical modification of PCL film by PANI and H2SO4. The conductivity of the films was increased by the coating of PANI to the patterned surface and additionally increased by the chemically modified PANI. The antibacterial activity was 69.79%, 78.27%, and 88% against E. coli, and 32.73%, 62.65%, and 87.97% against S. aureus, for flat PANI, HCP PANI, and H2SO4-treated HCP films, respectively. Likewise, the PANI coated flat, HCP, and H2SO4-treated HCP films inhibited E. coli biofilm formation by around 41.62%, 63%, and 83.88% and S. aureus biofilm formation by 17.81%, 69.83%, and 96.57%, respectively. The antibacterial activity of the HCP film was higher than that of flat PANI films, probably due to the higher coating of PANI on the HCP surface. Moreover, sulfonation of the HCP film with H2SO4 might have improved the wettability, thereby enhancing the antibacterial and antibiofilm properties. Our results showed that topographical changes, as well as doping, offer simple and cost-effective ways to modify the structural and functional properties of films. [ABSTRACT FROM AUTHOR]

Hafnia (HfO2) is a promising material for emerging chip applications due to its high-κ dielectric behavior, suitability for negative capacitance heterostructures, scalable ferroelectricity, and silicon compatibility. The lattice dynamics along with phononic properties such as thermal conductivity, contraction, and heat capacity are under-explored, primarily due to the absence of high quality single crystals. Herein, we report the vibrational properties of a series of HfO2 crystals stabilized with yttrium (chemical formula HfO2: xY, where x = 20, 12, 11, 8, and 0%) and compare our findings with a symmetry analysis and lattice dynamics calculations. We untangle the effects of Y by testing our calculations against the measured Raman and infrared spectra of the cubic, antipolar orthorhombic, and monoclinic phases and then proceed to reveal the signature modes of polar orthorhombic hafnia. This work provides a spectroscopic fingerprint for several different phases of HfO2 and paves the way for an analysis of mode contributions to high-κ dielectric and ferroelectric properties for chip technologies. [ABSTRACT FROM AUTHOR]

Four palladium(II) and mercury(II) complexes of the type [MCl2(HPAO)] or [M(PAO)2](HPAO = syn‐2‐pyridine aldoxime) are prepared and characterized using FTIR, 1H NMR spectra, molar conductivity, and melting point. The results demonstrated that a chelating bidentate behavior of APO through the indo and exocyclic nitrogen atoms. The applicability of the prepared complexes in hydrogen storage at a temperature of 77 K and a pressure of 100 bar is studied. The results show that the complexes are capable of storing hydrogen as follows: 1.54, 2.3, 0.53, and 0.63 wt.% of H2 for [Hg(HAPO)Cl2] (1), [Pd(HAPO)Cl2] (2), [Hg(APO)2] (3), and [Pd(APO)2] (4), respectively. Thermodynamic calculations show that the storage type of hydrogen is the physico‐absorption type. The study shows that the central metal has an effect on the ability of the complex to store hydrogen, as the palladium complexes are more capable of storing hydrogen than their mercury counterparts. [ABSTRACT FROM AUTHOR]

The Emperor Penguin (Aptenodytes forsteri), the largest extant penguin, inhabits exclusively in Antarctica. Little is known about the spine of this species; this work presents a description of the vertebral column of an adult of A. forsteri, compared with specimens from different ontogenetic stages (chick, fledgling, and juvenile). We also analyze the regionalization of the spine with a principal component analysis (PCA), and the modularity with an elliptical Fourier analysis, performing a PCA, followed by a linear discriminant analysis on the PC scores. Our results show that the vertebrae are completely ossified in adults, while the suture lines between the different elements are visible in the previous stages and some structures remain cartilaginous. A total of 42/43 vertebrae were counted (13 cervicals, 2 cervicothoracics, 6/7 thoracics, 13 synsacrals, and 8 caudals), and an extra vertebra appears in the thoracic region of one specimen. These regions are already differentiated in fledglings, but not in chicks. Six modules associated with the S-shape of the adult neck were recognized and are represented by different numbers of vertebrae: module 1 (C1), module 2 (C2), module 3 (C3–5), module 4 (C6), module 5 (C7–9) and module 6 (C10–13). Differences in the vertebral configuration in modules 5 and 6 of previous stages were found, where cervical 10 is part of module 5 due to the absence of the processus ventralis corporis. [ABSTRACT FROM AUTHOR]

GeSn alloys are promising materials for light emitters monolithically grown on silicon. In this work, we demonstrate room temperature (RT) lasing in a GeSn hetero-structure with 17.2% of Sn. We report a threshold of 3.27 MW c m − 2 at 305 K with peak emission at 353 meV. We ascribe these improvements to a higher tin concentration in the GeSn active layer with lower Sn content barriers on each side and to a better thermal dissipation provided by an adapted pedestal architecture beneath the GeSn micro-disk. This outcome is a major milestone for a fully integrated group-IV semiconductor laser on Si. [ABSTRACT FROM AUTHOR]

In the present study gelatin coated-gold nanoparticles were synthesized and release study of the drug "5-fluorouracil" (5-FU) was carried out in a controlled manner. Gelatin nanoparticles were prepared by single water in oil (W/O) emulsion crosslinking technique and gold (Au) nanoparticles by Turkvitch method. For preparing gelatin coated-Au nanoparticles, in situ method was adopted. The release kinetics of entrapped drug was investigated as a function of various experimental factors such as chemical composition of prepared nanoparticles, pH, temperature and simulated biological fluids as the release media. The 5-FU drug loaded nanoparticles were characterized by FTIR, SEM, TEM, XRD and in vitro cytotoxicity techniques. The drug release process was analyzed kinetically using Fickian power law, zero order, first order and Korsmeyer–Peppas models, respectively, and a correlation was established between the quantity of the released drug and swelling of the nanoparticles. [ABSTRACT FROM AUTHOR]

Pseudomorphic GeSn layers with Sn atomic percentages between 4.5% and 11.3% were grown by chemical vapor deposition using digermane and SnCl4 precursors on Ge virtual substrates grown on Si. The layers were characterized by x-ray diffraction rocking curves and reciprocal space maps. Photoconductive devices were fabricated, and the dark current was found to increase with Sn concentration. The responsivity of the photoconductors was measured at a wavelength of 1.55 µm using calibrated laser illumination at room temperature and a maximum value of 2.7mA/W was measured for a 4.5% Sn device. Moreover, the responsivity for higher Sn concentration was found to increase with decreasing temperature. Spectral photoconductivity was measured using Fourier transform infrared spectroscopy. The photoconductive absorption edge continually increased in wavelength with increasing tin percentage, out to approximately 2.4 µm for an 11.3% Sn device. The direct band gap was extracted using Tauc plots and was fit to a bandgap model accounting for layer strain and Sn concentration. This direct bandgap was attributed to absorption from the heavy-hole band to the conduction band. Higher energy absorption was also observed, which was thought to be likely from absorption in the light-hole band. The band gaps for these alloys were plotted as a function of temperature. These experiments show the promise of GeSn alloys for CMOS compatible short wave infrared detectors. [ABSTRACT FROM AUTHOR]

The wet etching of germanium-tin (Ge1-xSnx) alloys (4.2%1-xSnx is proportional to the square root of the etch time t and decreases exponentially with increasing x for a given t. In addition, X-ray photoelectron spectroscopy results show that increasing t increases the intensity of the Sn oxide peak, whereas no obvious change is observed for the Ge oxide peak. This indicates that an accumulation of Sn oxide on the Ge1-xSnx surface decreases the amount of Ge atoms exposed to the etchant, which accounts for the decrease in etch rate with increasing etch time. Atomic force microscopy was used to examine the surface morphologies of the Ge0.918Sn0.082 samples. Both root-mean-square roughness and undulation periods of the Ge1-xSnx surface were observed to increase with increasing t. This work provides further understanding of the wet etching of Ge1-xSnx using APM and may be used for the fabrication of Ge1-xSnx-based electronic and photonic devices. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the hardness of a dual-curing self-adhesive resin cement (RelyX U200) and a conventional dual-curing resin cement (RelyX ARC) cured with different light curing units of different wavelengths (Elipar Freelight 2 LED [430 to 480 nm, conventional], Bluephase LED [380 to 515 nm, polywave], AccuCure 3000 Laser [488 nm]) by means of the nanoindentation test. Materials and Methods: Bovine incisors were cleaned and then sectioned at the cementoenamel junction to remove the crown. After embedding in acrylic, dentin surfaces of the specimens were exposed and ground flat to standardize the surfaces. To simulate clinically placing indirect restorations, ceramic (IPS e.maxPress/lvoclar Vivadent) or indirect composite resin (SR Adoro/lvoclar Vivadent) slabs were cemented on dentin surfaces. The specimens were sectioned longitudinally at low speed under constant irrigation and then polished. In the positive control group, the cement was light cured without the interposition of indirect restorative material; in the negative control group, after the indirect restorative material was cemented, no light curing was performed, allowing only chemical polymerization of the cement. All specimens were stored in distilled water at 37°C for 7 days. Nanoindentadion hardness of the cement layer was measured under a 100-mN load. Data were statistically analyzed using ANOVA and Tukey's test (p < 0.05). Results: Although the self-adhesive cement is technically simple, conventional cement showed the best polymerization performance. The polywave LED technology did not differ significantly from other light-curing units. The hardness of the resin cements evaluated was negatively influenced by the interposition of an indirect restorative material; only the LEDs were able to maintain the same degree of cement polymerization when an indirect restorative material was used. Conclusion: The photoactivation step is required during the cementation of indirect restorations to ensure adequate polymerization of dual-curing resin cements. [ABSTRACT FROM AUTHOR]

The severe COVID‐19 pandemic requires the development of novel, rapid, accurate, and label‐free techniques that facilitate the detection and discrimination of SARS‐CoV‐2 infected subjects. Raman spectroscopy has been used to diagnose COVID‐19 in serum samples of suspected patients without clinical symptoms of COVID‐19 but presented positive immunoglobulins M and G (IgM and IgG) assays versus Control (negative IgM and IgG). A dispersive Raman spectrometer (830 nm, 350 mW) was employed, and triplicate spectra were obtained. A total of 278 spectra were used from 94 serum samples (54 Control and 40 COVID‐19). The main spectral differences between the positive IgM and IgG versus Control, evaluated by principal component analysis (PCA), were features assigned to proteins including albumin (lower in the group COVID‐19 and in the group IgM/IgG and IgG positive) and features assigned to lipids, phospholipids, and carotenoids (higher the group COVID‐19 and in the group IgM/IgG positive). Features referred to nucleic acids, tryptophan, and immunoglobulins were also seen (higher the group COVID‐19). A discriminant model based on partial least squares regression (PLS‐DA) found sensitivity of 84.0%, specificity of 95.0%, and accuracy of 90.3% for discriminating positive Ig groups versus Control. When considering individual Ig group versus Control, it was found sensitivity of 77.3%, specificity of 97.5%, and accuracy of 88.8%. The higher classification error was found for the IgM group (no success classification). Raman spectroscopy may become a technique of choice for rapid serological evaluation aiming COVID‐19 diagnosis, mainly detecting the presence of IgM/IgG and IgG after COVID‐19 infection. [ABSTRACT FROM AUTHOR]

Ovarian cancer is a multifactorial and deadly disease. Despite significant advancements in ovarian cancer therapy, its incidence is on the rise and the molecular mechanisms underlying ovarian cancer invasiveness, metastasis and drug resistance remain largely elusive, resulting in poor prognosis. Oncolytic viruses armed with therapeutic transgenes of interest offer an attractive alternative to chemical drugs, which often face innate and acquired drug resistance. The present study constructed a novel oncolytic adenovirus carrying ERCC1 short interfering (si)RNA, regulated by hTERT and HIF promoters, termed Ad-siERCC1. The findings demonstrated that this oncolytic adenovirus effectively inhibits the proliferation, migration and invasion of ovarian cancer cells. Furthermore, the downregulation of ERCC1 expression by siRNA ameliorates drug resistance to cisplatin (DDP) chemotherapy. It was found that Ad-siERCC1 blocks the cell cycle in the G1 phase and enhances apoptosis through the PI3K/AKT-caspase-3 signaling pathways in SKOV3 cells. The results of the present study highlighted the critical effect of oncolytic virus Ad-siERCC1 in inhibiting the survival of ovarian cancer cells and increasing chemotherapy sensitivity to DDP. These findings underscore the potent antitumor effect of Ad-siERCC1 on ovarian cancers in vivo. [ABSTRACT FROM AUTHOR]

The combination of a growing number of complex technologies in internal combustion engines (ICE) is commonplace, due to the need of complying with the tight pollutant regulations and achieving high efficiencies. Hence the work of calibration engineers is led by a constant increase in degrees of freedom in ICE design. In this research work, a wide analysis on the optimization of combined variable valve timing (VVT) and exhaust gases recirculation (EGR) strategies is developed, in order to reduce fuel consumption in a EURO 6 1.3l 4-stroke 4-cylinder, gasoline, turbocharged, direct-injection engine, also equipped with a variable nozzle turbine (VNT). For that purpose, a methodology which combines 1D engine simulations with limited experimental work was applied. First, the data from 25 experimental tests distributed into three steady engine operating conditions was used to calibrate a 1D model. Then, modeling parametric studies were performed to optimize VVT and EGR parameters. A total of 150 cases were simulated for each operating point, in which VVT settings and EGR rate were varied at iso-air mass flow and iso-intake manifold temperature. The optimization was based on finding the configuration of VVT and EGR systems which maximizes the indicated efficiency. All different cases modeled were also evaluated in terms of pumping and heat losses. Moreover, a deep assessment of instantaneous pressure traces and mass flows in intake and exhaust valves was given, to provide insights about the optimization procedure. Finally, the findings obtained by simulation were compared with the results from a design of experiments (DOE) composed of more than 300 tests, and the impact on engine fuel consumption was analyzed. [ABSTRACT FROM AUTHOR]

The MCAW with rotating electrode process (MCAW-RE) is a variation of the conventional MCAW (metal-cored arc welding) process, where reduced costs and superior productivity are obtained due to narrow gap welding, since the rotational motion of the electrode allows the electric arc to reach peripheral regions of the groove, preventing lack of fusion on the sidewall. Although there is some information about the operational characteristics of this process, the literature studying the mechanical properties is very limited. This work evaluates the mechanical and microstructural properties of high strength steel weld metals obtained by the MCAW-RE using two different mixtures of Ar-CO2 as shielding gas. Multipass welding by MCAW-RE was performed with preheating of 100 °C, in 500 × 150 × 10 mm steel plates. Weld metals were obtained by the MCAW-RE process using a consumable of the class 700 MPa and two mixtures of Ar-CO2 (5% CO2 and 25% CO2) as shielding gas. The results obtained from mechanical tests (hardness and impact Charpy-V) and metallographic examination (optical microscopy, scanning electron microscopy, and electron backscattering diffraction) carried out in samples removed transversally to the weld bead showed equivalent results for all weld metals. These results evidenced that the MCAW-RE process can provide weld metals with satisfactory behavior with different shielding gases. This process has a high potential for replacement of the conventional GMAW process because the weld metals achieved the requirements for several industrial applications. [ABSTRACT FROM AUTHOR]

Copyright of Piezoelectrics & Acoustooptics is the property of Piezoelectric & Acoustooptic and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

For smart cities using clean energy, optimal energy management has made the development of electric vehicles more popular. However, the fear of range anxiety—that a vehicle has insufficient range to reach its destination—is slowing down the adoption of EVs. The integration of an auxiliary power unit (APU) can extend the range of a vehicle, making them more attractive to consumers. The increased interest in optimizing electric vehicles is generating research around range extenders. These days, many systems and configurations of extended-range electric vehicles (EREVs) have been proposed to recover energy. However, it is necessary to summarize all those efforts made by researchers and industry to find the optimal solution regarding range extenders. This paper analyzes the most relevant technologies that recover energy, the current topologies and configurations of EREVs, and the state-of-the-art in control methods used to manage energy. The analysis presented mainly focuses on finding maximum fuel economy, reducing emissions, minimizing the system's costs, and providing optimal driving performance. Our summary and evaluation of range extenders for electric vehicles seeks to guide researchers and automakers to generate new topologies and configurations for EVs with optimized range, improved functionality, and low emissions. [ABSTRACT FROM AUTHOR]

Adopting in-wheel motor drive can improve vehicle dynamics control functions, which is the most ideal drive mode of unmanned ground vehicle. However, with the increase of the heavy unspring-mass vibration energy while the vehicle running on uneven road, the ride comfort will be seriously deteriorated. To solve the problem and save energy, the ride comfort control based on regenerative suspensions is adopted. By analyzing the vibration performance, the adverse effects of the vehicle equipped in-wheel motors with passive suspensions are revealed. Then, the dynamics model of the regenerative suspension is built. Based on the suspension power recovery, the multi-state optimal control strategy for improving the ride comfort is designed. Finally, comparing the simulation results of regenerative suspensions with the test results of passive suspensions, when the vehicle mass ratio decreases from 8:1 to 4:1, the body acceleration and the root mean square value of tire dynamic load increase by 28.1% and 31.6%, correspondingly. With the control method, the body acceleration is decreased by 23% and reaches the level of conventional vehicles. Furthermore, part of the vehicle vibration energy can be recovered and the vehicle driving range can be extended. [ABSTRACT FROM AUTHOR]

The effect of curing mode of dual-cure resin cements on the tensile bond strength (TBS) of universal adhesives to enamel, dentin, zirconia, lithium disilicate ceramics (LDS), feldspathic porcelain (FP), and a Pd-Au alloy was evaluated. The substrates were bonded using Tokuyama Universal Bond (TUB) or Scotchbond Universal Adhesive (SBU), followed by luting with Estecem II (ECII) or Rely-X Ultimate (RXU), respectively, which were used either in light-curing or self-curing mode. The TBS test was performed after 24 h or 5,000 thermal cycles. Light-curing significantly improved the 24-h TBS of TUB/ECII to enamel, dentin and FP, as well as the TBS of SBU/RXU to all substrates except LDS. After thermal cycling, light-curing significantly increased the TBS of both adhesives/cements to dentin, but significant differences between curing modes were seldom observed for other substrates. This suggested that lightcuring is essential for the hydrophilic dentin, but self-curing might be sufficient for other substrates. [ABSTRACT FROM AUTHOR]

Semiconductor membranes emerged as a versatile class of nanomaterials to control lattice strain and engineer complex heterostructures enabling a variety of innovative applications. With this perspective, herein this platform is exploited to tune simultaneously the lattice parameter and bandgap energy in group IV GeSn semiconductor alloys. As Sn content is increased to reach a direct bandgap, these semiconductors become metastable and typically compressively strained. It is shown that the relaxation in released membranes extends the absorption wavelength range deeper in the mid‐infrared. Fully released Ge0.83Sn0.17 membranes are integrated on silicon and used in the fabrication of broadband photodetectors operating at room temperature with a record wavelength cutoff of 4.6 µm, without compromising the performance at shorter wavelengths down to 2.3 µm. These membrane devices are characterized by two orders of magnitude reduction in dark current as compared to as‐grown strained epitaxial layers. A variety of experimental tools and optimized calculations are used to discuss the crystalline quality, composition uniformity, lattice strain, and the electronic band structure of the investigated materials and devices. The ability to engineer all‐group IV transferable mid‐infrared photodetectors lays the groundwork to implement scalable and flexible sensing and imaging technologies exploiting these integrative, silicon‐compatible strained‐relaxed GeSn membranes. [ABSTRACT FROM AUTHOR]

Huge thermal noise owing to the narrow energy bandgap is one of the critical issues for group IV-based photonics in the mid-infrared regime. With this motivation, we examined to form Ge1−xSnx/Ge1−x−ySixSny quantum heterostructures (QHs) by molecular beam epitaxy for realizing resonant tunneling diodes composed of group-IV materials. We confirmed the formation of approximately 2 nm-thick Ge1−xSnx/Ge1−x−ySixSny QHs with atomically flat interfaces by x-ray diffraction and transmission electron microscopy methods. Moreover, by the current density–voltage (J–V) measurement at 10 K, we observed the occurrence of a non-linear distinct hump in the J–V characteristic, which is possibly originated from quantum transport of heavy holes. According to the tunneling transmission spectra simulation result, the hump property would be due to two possible scenarios: a resonant tunneling of heavy holes in the QH and/or a resonance phenomenon that heavy holes pass just above a potential barrier. [ABSTRACT FROM AUTHOR]

Copyright of Somnologie is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

We have proposed and successfully demonstrated the operation principle of the energy harvesting method with multi-dielectric layer capacitors in a temperature fluctuating environment, and showed that the temperature coefficient of the flat-band voltage (VFB) is one of the important factors to enhance its efficiency. Next, we investigated the impact of densities of both SiO2 and Al2O3 deposited films on measurement temperature dependence of the Al2O3/SiO2 interface dipole layer strength. A positive temperature coefficient of dipole layer strength was pronounced only when SiO2 was grown at a high temperature and Al2O3 was annealed at low temperature. It was suggested that both oxides were required to have a lower density for the positive temperature coefficient. These results indicate a guideline to control the temperature coefficient of dipole layer strength of a Al2O3/SiO2/Al2O3/SiO2··· multilayer stack, which is one of the important factors to determine the efficiency of the proposed energy harvesting method. [ABSTRACT FROM AUTHOR]

We report an investigation of a planar GeSn p–i–n diode for a high-detectivity photodetector based on an undoped GeSn film. By fabricating n- and p-type regions on the plane of the GeSn film using the complementary metal–oxide–semiconductor technology of ion implantation, a low dark current density is revealed and attributed to the low defect density of the film and current flow suppression around the diode periphery. This yields a specific 1550-nm detectivity of ∼1010 cm Hz1/2 W−1, an order of magnitude higher than that of conventional vertical GeSn-based diodes and comparable to that of commercially available Ge-based diodes. This work provides an alternative approach for achieving a high-detectivity GeSn photodetector that may facilitate its potential applications. [ABSTRACT FROM AUTHOR]

Reductions in genetic diversity and genetic connectivity have been documented in some predatory bird species in response to anthropogenic habitat fragmentation. The Southern Boobook (Ninox boobook) is the most common and widely-distributed owl in Australia but declines in abundance have been observed across its range. We used polymorphic microsatellite loci to investigate landscape-scale patterns of genetic variation and spatial genetic structure in boobooks from a variety of fragmented landscape types and relatively undisturbed landscape types across Western Australia. The maximum distance between collection locations of genetic samples was 1391 km. Indirect estimates of connectivity inferred from these genetic data were complemented by direct estimates of post-breeding dispersal of juvenile boobooks gathered from banding data resulting from this and other studies across Australia. We found high genetic diversity in microsatellite markers, weak spatial genetic structuring and no evidence of genetic erosion associated with inbreeding in heavily fragmented landscapes. Bayesian modelling, spatial autocorrelation analysis and principal coordinates analysis suggested a single large panmictic population across all areas sampled. Within the heavily fragmented landscape of an extensive urban area, band re-sightings and recoveries substantiate the considerable capacity of juvenile boobooks to disperse across areas far greater than the distance between patches. We hypothesise that the genetic homogeneity observed in this species is a consequence of long-distance dispersal capacity in addition to their ability as habitat and dietary generalists to make use of highly altered habitats. [ABSTRACT FROM AUTHOR]