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The molecular mechanisms of glioblastoma (GBM) are unclear, and the prognosis is poor. Spinster homolog 2 (SPNS2) is reportedly involved in pathological processes such as immune response, vascular development, and cancer. However, the biological function and molecular role of SPNS2 in GBM are unclear. SPNS2 is aberrantly low expressed in glioma. Survival curves, risk scores, prognostic nomograms, and univariate and multifactorial Cox regression analyses showed that SPNS2 is an independent prognostic indicator significantly associated with glioma progression and prognosis. Cell function assays and in vivo xenograft transplantation were performed that downregulation of SPNS2 promoted GBM cell growth, migration, invasion, epithelial–mesenchymal transition (EMT), anti‐apoptosis, drug resistance, and stemness, while overexpression of SPNS2 had the opposite effect. Meanwhile, the functional enrichment and signaling pathways of SPNS2 in the Cancer Genome Atlas (TCGA), Chinese Glioma Genome Atlas (CGGA), and RNA sequencing were analyzed by Gene ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and Gene set enrichment analysis (GSEA). The above results were related to the inhibition of the PTEN/PI3K/AKT pathway by SPNS2. In addition, we predicted that SPNS2 is closely associated with immune infiltration in the tumor microenvironment by four immune algorithms, ESTIMATE, TIMER, CIBERSORT, and QUANTISEQ. In particular, SPNS2 was negatively correlated with the infiltration of most immune cells, immunomodulators, and chemokines. Finally, single‐cell sequencing analysis also revealed that SPNS2 was remarkably correlated with macrophages, and downregulation of SPNS2 promotes the expression of M2‐like macrophages. This study provides new evidence that SPNS2 inhibits malignant progression, stemness, and immune infiltration of GBM cells through PTEN/PI3K/AKT pathway. SPNS2 may become a new diagnostic indicator and potential immunotherapeutic target for glioma. [ABSTRACT FROM AUTHOR]

Few-shot learning aims to recognize new visual concepts with a small number of labeled samples. The hierarchical structure based on inter-class labels performs well in many few-shot learning models. However, intra-class features are similar and difficult to distinguish, which is important for mining the correlation and independence between intra-class features in the scene of sparse data. In this paper, we propose a few-shot learning model with a self-similarity feature representation by a hierarchical relation network, which considers inter-class labels and intra-class features to guide few-shot learning. First, we introduce a self-similarity feature representation module as the intermediate feature transform in the neural network. Unlike the traditional model, it extracts specific feature information from intra-class features. Second, we leverage the inter-class label hierarchical structure as important auxiliary information to establish a hierarchical relation network metric module. The module uses coarse-grained information to guide fine-grained classification, which effectively alleviates the problem of insufficient data. Experimental results show that our model improves the classification accuracy, reaching 58.68% on the tieredImageNet dataset. [ABSTRACT FROM AUTHOR]

A series of Co/Mn compensated Ca3Co1+xMn1-xO6 compounds were synthesized. The structure and magnetization were characterized, as well as the dielectric properties were studied. In Co/Mn compensated samples, the well-ranked Co/Mn ionic order is destroyed which manifests the suppression of the formation of the short-range magnetic order. As a result, the freezing anomaly around Tf = 150 K diminishes. For the two Co/Mn compensated samples, the critical field HSF that causes magnetic structure change from ↑↑↓↓ state to ↑↑↓↑ state also increases. The appearance of dielectric peak at the antiferromagnetic phase transition temperature clearly indicates the coupling effect between the spin dipole and electric dipole. The temperature corresponding to the dielectric peak increases with the increasing measurement frequency. The frequency dependence of ferroelectric peak identifies relaxor ferroelectric nature. In dielectric measurements associated with magnetic fields, Δε` and Δtanδ have the same sign elucidating intrinsic magnetodielectric effect of Ca3Co1+xMn1-xO6. For the Co/Mn compensated x = ±0.05 two samples, the suppressed magnetic short-range order also leads to a low diffusion exponent γ and the weak relaxor ferroelectric nature. The thermal activation process of the dipole response is characterized by the Vogel–Fulcher equation and the results confirm that the freezing process of Ca3Co1+xMn1-xO6 is mainly dominated by coupling of polar nanodomains. [ABSTRACT FROM AUTHOR]

This paper reports the synthesis, microstructure and electrical properties of a new Ba4SrBiTi3Nb7O30 ceramic. X-ray diffraction analysis shows that the sample crystallizes into tungsten bronze structure, and the space group is P4bm. The electrical measurement results show that Ba4SrBiTi3Nb7O30 exhibits good dielectric and ferroelectric properties. The temperature-dependent dielectric permittivity indicates that the transition temperature of the prepared Ba4SrBiTi3Nb7O30 sample is around Tm ≈ 250K. With increasing the frequency, the dielectric peak moves to a lower temperature. Below 250 K, obvious polarization current can be detected, corresponding to the formation of spontaneous ferroelectric polarization. These results indicate the relaxor ferroelectric behavior of Ba4SrBiTi3Nb7O30 ceramic. [ABSTRACT FROM AUTHOR]

This study investigated children's perspectives on preschool teachers' roles in Taiwan's changing cultural setting. This study attempted to examine how aspects of culture and time are interwoven in children's lives. Data were collected through children's drawings, the photographs they captured and drawing‐photo elicitation interviews. The data were analysed to identify the eight types of teachers' roles and the time points at which the children observed the roles. The children noted that their teachers were 'regulators'; however, they also discovered teachers' interactive and democratic roles in less structured settings during the time of learning areas and while outdoors. [ABSTRACT FROM AUTHOR]

The current study explores Taiwanese preschool children's understanding of the value of caring in school. This study offers researchers and practitioners opportunities to study children's perspectives in a particular cultural setting and discuss the connectedness of culture and children's views on caring. Participatory research and qualitative methods were used, encompassing the collecting of children's speech, photography, and drawings. The findings regarding the understanding of caring indicated the following: (1) Children interpret caring among peers and from school surroundings; (2) children perceive teacher care in daily classroom routines; (3) children learn about values when outdoors, in learning areas, and during transition times; and (4) children exhibit the ability to distinguish non-caring behaviour. This study shows that for children caring was most frequently defined as helping others in need and as teacher care in daily routines. The children's views on caring were influenced by culture, and they created meanings for caring. [ABSTRACT FROM AUTHOR]

Objectives: To investigate the value of preoperative positron emission tomography/computed tomography (PET/CT) in differentiating the invasive degree of hypometabolic lung adenocarcinoma. Methods: We retrospectively analyzed the data of patients who underwent PET/CT examination, high-resolution computed tomography, and surgical resection for low-metabolism lung adenocarcinoma in our hospital between June 2016 and December 2021. We also investigated the relationship between the preoperative PET/CT findings and the pathological subtype of hypometabolic lung adenocarcinoma. Results: A total of 128 lesions were found in 113 patients who underwent resection for lung adenocarcinoma, including 20 minimally invasive adenocarcinomas (MIA) and 108 invasive adenocarcinomas (IAC), whose preoperative PET/CT showed low metabolism. There were significant differences in the largest diameter (Dmax), lesion type, maximum standard uptake value (SUVmax), SUVindex (the ratio of SUVmax of lesion to SUVmax of contralateral normal lung paranchyma), fasting blood glucose, lobulation, spiculation, and pleura indentation between the MIA and IAC groups (p < 0.05). Multivariate logistic regression analysis showed that the Dmax (odds ratio (OR) = 1.413, 95% confidence interval (CI: 1.155–1.729, p = 0.001)) and SUVmax (OR = 12.137, 95% CI: 1.068–137.900, p = 0.044) were independent risk factors for predicting the hypometabolic IAC (p < 0.05). Receiver operating characteristic (ROC) curve analysis showed that the Dmax ≥ 10.5 mm and SUVmax ≥ 0.85 were the cut-off values for differentiating MIA from IAC, with high sensitivity (84.3% and 75.9%, respectively) and specificity (84.5% and 85.0%, respectively), the Combined Diagnosis showed higher sensitivity (91.7%) and specificity (85.0%). Conclusions: The PET/CT findings correlated with the subtype of hypometabolic lung adenocarcinoma. The parameters Dmax and SUVmax were independent risk factors for predicting IAC, and the sensitivity of Combined Diagnosis prediction is better. [ABSTRACT FROM AUTHOR]

Few-shot learning, which aims to identify new classes with very few samples, is an increasingly popular and crucial research topic in the machine learning. Many models use distance measurement to determine similarities among single samples and achieve accurate classification results. However, distance calculations incur substantial costs and time based on a single sample, and the linear measurement model cannot accurately represent the differences and connections between samples. This paper proposes a coarse-grained granulation relation network (CGRN) model for few-shot classification. First, all the single samples of each class are clustered into coarse grain to represent the feature information of all the class samples, which can significantly reduce computational complexities. Second, a relation network is built to measure the degree of similarity among the test samples and the coarse grain obtained above, which can reveal the differences and connections between the samples. The experimental results demonstrate that this model outperforms some popular distance measurement-based few-shot learning models. For example, CGRN is at least 0.5% better than other models in 20-way 5-shot on the Omniglot dataset and achieves 0.8% improvement over the second-best model in 5-way 1-shot on the tiered-ImageNet dataset. [ABSTRACT FROM AUTHOR]

In modern times, with the development of industrialized society and the invention of clocks and watches, people have become more and more concerned about institutionalization, and higher education time and space have also shown the characteristics of institutionalization. In modern times, educational informatization has brought challenges and opportunities for educational reform and development. The vigorous development of education informatization has also produced changes in higher education spatiotemporally. For example, the rise of catechism and online learning, the importance of fragmented time, the development of space toward virtualization, and the expansion of interactive space for interpersonal interactions. In addition, the enrichment and sharing of educational materials, the informatization, and big data of educational management also contribute to the improvement of time efficiency and optimization of time structure in higher education. With the background of education under the new normal, this paper briefly analyzes the current situation of education informatization construction in colleges and universities from the perspective of education managers, and addresses the current situation and problems of teaching management informatization construction, such as organizational structure dominated by pyramidal functional departments, inefficiency, inability to connect work, difficulty in work gap, difficulty in horizontal coordination, and closed information. A work breakdown structure (WBS) based project management theory and work structure decomposition method are proposed. This paper finds that the improved association rule mining algorithm can improve the efficiency of teaching management practice in colleges and universities by more than 14.58%, which is an important reference value for college management informatization. [ABSTRACT FROM AUTHOR]

In this paper, the GdCrO3 polycrystalline samples with different particle sizes were prepared by the sol–gel method and the structure, vacancy defects, magnetocaloric property, dielectric property were investigated in detail. The results indicate that the lattice constant and vacancy defects can be affected greatly by the particle size. With the particle sizes increases, the magnetic entropy becomes larger at first, and then it decreases accompanying particle size becomes larger than 395 nm. That is, the d = 395 nm sample presents the best magnetocaloric property and the maximum magnetic entropy (− ΔSM) and the refrigerant capacity (RCP) at T = 3 K and H = 3 T condition is 33.41 J·kg−1 K−1 and 552.4 J kg−1. The temperature and magnetic field dependent permittivity also confirm the magneto-dielectric effect of the prepared GdCrO3. As the particle size increases, the coupling coefficient enhanced continuously. Especially for the d = 485 nm sample, a small field of 1 T could cause the dielectric constant increases by about 10%. This work suggests that increasing the particle size is an effective method for improving the magnetocaloric and magnetoelectric properties of GdCrO3. [ABSTRACT FROM AUTHOR]

Polycrystalline GdCrO3 was synthesized by the solid-state reaction method. The temperature-dependent microstructure and magnetic properties were investigated systematically. Both the Raman and FTIR spectra indicate a microstructure anomaly around 170 K. Magnetic studies demonstrate that the sample experiences two magnetic transitions around TN(Cr) ~ 167 K and TN(Gd) ~ 2.8 K related to the AFM Cr3+–Cr3+ interaction and Gd3+–Gd3+ interaction. Interestingly, the ferrimagnetic interaction between Gd and Cr ions results in the temperature-dependent magnetic reversal (TMR) together with a spin flipping (SF) that occurs at Tmin ~ 25.7 K. Due to the anisotropic exchange interaction of the Gd3+–Cr3+, a spin reorientation (SR) from Г4 (Gx, Ay, Fz) phase to Г2 (Fx, Cy, Gz) phase occurs at TSR ~ 7.8 K. In addition, a giant magnetocaloric effect (MCE) caused by the second-order AFM phase transition of Gd3+ ordering is observed at T = 3 K and H = 3 T with a magnetic entropy of − ΔSM ~ 32.8 J/kg⋅K. The present research suggests that GdCrO3 can be considered as a potential candidate material for applying in magnetic refrigeration. [ABSTRACT FROM AUTHOR]

Previous reports depict that the nonstoichiometric Co/Mn ratio greatly affects the physical properties of Ca3CoMnO6, but few papers focus on the Co/Mn site doping effect. In order to investigate the influence of the substitution on the magnetization, partial Mn4+ ions were replaced with Al3+ ions and polycrystalline Ca3CoMn1-xAlxO6 (x = 0, 0.05, 0.1, 0.15, 0.2) samples were prepared. All the samples crystallized into rhombohedral structure without existence of impurities. SEM patterns showed that the mean particle size decreased with the introduction of Al element. Due to the dilution effect of nonmagnetic Al3+ ions to the spin chains, the competing short-range antiferromagnetic/ferromagnetic order caused by the "order by disorder" phenomenon was suppressed. The high-temperature spin freezing peak disappeared gradually and the doped samples presented a faster dynamic behavior, indicating a more robust long-range antiferromagnetic order. The time-dependent magnetization showed a nonmonotonic relaxation in a field of 5T, implying the possible existence of quantum tunneling of magnetization. Highlights: Doping with nonmagnetic Al3+ weaks the formation of short range magnetic order and help to establish a more robust long rang antiferromagnetic order in Ca3CoMnO6. The dilution effect causes the high-temperature spin freezing peak disappears gradually and a faster dynamic behavior is observed. Nonmonotonic relaxation implies the possible existence of quantum tunneling of magnetization. [ABSTRACT FROM AUTHOR]

The Ca3CoMn1-xTixO6(x = 0, 0.05) samples were synthesized by a modified sol-gel method, and the microstructure, microtopography, and magnetic properties were investigated in detail. With substituting of Mn4+ ions by Ti4+ ions, the crystallinity and particle size of Ca3CoMn1-xTixO6 (x = 0, 0.05) samples decrease. The Ti4+ doping also causes the high-temperature spin freezing phenomenon disappears, and the transition field of ↑↑↓↓ magnetic structure to ↑↑↑↓ magnetic structure increases obviously together with the faster dynamic behavior. These results suggest that the dilution effect of Ti4+ doping to Co-Mn-Co-Mn spin chains could reduce the degree of magnetic frustration and suppress the formation of short range magnetic order, for which will be beneficial for the establishment of more robust long range antiferromagnetic structure. The present research could serve as a reference on tuning the magnetic order and improving the multiferroic property of Ca3CoMnO6. [ABSTRACT FROM AUTHOR]

Top‐down spatial attention can modulate contingent attentional capture, but the underlying mechanism is still not clear. Using variants of spatial cueing paradigms, our previous event‐related potential study showed that peripheral color singleton cues with task‐relevant features captured attention (indexed by cue‐elicited N2pc) even when the targets appeared at central locations, but the magnitude of attentional capture was smaller than when the targets appeared at same peripheral locations. One reasonable explanation is that the modulation effect is due to spatial relevance of cues. However, several other confounding factors might also explain the modulation effect, such as task difficulty, spread of attentional window, and inside/outside relation between cue and attentional window. In the present study, we rearranged the relative locations between cues and targets to control these factors and to further examine whether inequivalence of attentional capture across attended and unattended locations was a common phenomenon. In two experiments, color singleton cues elicited apparent N2pc components when participants were searching for targets possessing the same color, which replicated typical findings of contingent attentional capture. More importantly, the modulation effect of top‐down spatial attention on the cue‐elicited N2pc still existed even when the factors of task difficulty (Experiment 1), spread of attentional window (Experiment 1), or inside/outside relation between cue and attentional window (Experiment 2) were controlled. These results consistently demonstrate that attentional capture by a color singleton is stronger at spatially relevant locations than at spatially irrelevant locations, suggesting an important role of spatial relevance on contingent attentional capture. Using cue‐elicited N2pc as an index, we provide strong electrophysiological evidence supporting that attentional capture by a color singleton is not equivalent across locations and such effects could be accounted by spatial relevance itself. Our findings contribute to understanding the neural mechanisms underlying the collaboration of feature‐based and space‐based attention. [ABSTRACT FROM AUTHOR]

Oxygen vacancies have a profound effect on the magnetic, electronic, and transport properties of transition metal oxides but little is known about their effect on thermal expansion. Herein we report the effect of oxygen defects on the structure formation and thermal expansion properties of the layered perovskite Ca2RuO4 (CRO). It is shown that the CRO containing excess oxygen crystallizes in a metallic L-CRO phase without structure transition from 100 K to 500 K and displays a normal thermal expansion behavior, whereas those with oxygen vacancies adopt at room temperature an insulating S-CRO phase and exhibit an enormous negative thermal expansion (NTE) from 100 K to about 360 K, from where they undergo a structure transition to a high temperature metallic L-CRO phase. Compared to the L-CRO containing excess oxygen, the S-CRO structure has increasingly large orthorhombic strain and distinctive in-plane distortion upon cooling. The in-plane distortion of the RuO6 octahedra reaches a maximum across 260 K and then relaxes monotonically, providing a structure evidence for the appearance of an antiferromagnetic orbital ordering in the paramagnetic phase and the Ag phonon mode suppression and phase flip across the same temperature found recently. Both the L- and S-CRO display an antiferromagnetic ordering at about 150–110 K, with ferromagnetic ordering components at lower temperature. The NTE in S-CRO is a result of a complex interplay among the spin, orbital, and lattice. [ABSTRACT FROM AUTHOR]

Ba4SmFe0.5Nb9.5O30 ceramics were prepared by solid-state reaction method and the sample crystallized into single phase tungsten bronze (TB) structure with space group P4bm. The absence of dielectric peak suggests that there is no long-range ferroelectric order exists above room temperature (RT). Therefore, the observed ferroelectric property should be related to the polar nanoregions that survived to Burns temperature TB. Obvious RT ferromagnetism is observed for the first time in Ba4SmFe0.5Nb9.5O30 ceramics and it could be interpreted as the effective exchange coupling interaction between oxygen vacancies and Fe ions 3d spins, while the isolated Fe ions create the paramagnetic characteristic. In addition, the RT ferromagnetism and ferroelectricity also confirms that introduce of Fe ions could help to change TB structural ferroelectric to RT multiferroic material effectively. [ABSTRACT FROM AUTHOR]

Oxygen vacancies have a profound effect on the magnetic, electronic, and transport properties of transition metal oxides but little is known about their effect on thermal expansion. Herein we report the effect of oxygen defects on the structure formation and thermal expansion properties of the layered perovskite Ca2RuO4 (CRO). It is shown that the CRO containing excess oxygen crystallizes in a metallic L-CRO phase without structure transition from 100 K to 500 K and displays a normal thermal expansion behavior, whereas those with oxygen vacancies adopt at room temperature an insulating S-CRO phase and exhibit an enormous negative thermal expansion (NTE) from 100 K to about 360 K, from where they undergo a structure transition to a high temperature metallic L-CRO phase. Compared to the L-CRO containing excess oxygen, the S-CRO structure has increasingly large orthorhombic strain and distinctive in-plane distortion upon cooling. The in-plane distortion of the RuO6 octahedra reaches a maximum across 260 K and then relaxes monotonically, providing a structure evidence for the appearance of an antiferromagnetic orbital ordering in the paramagnetic phase and the Ag phonon mode suppression and phase flip across the same temperature found recently. Both the L- and S-CRO display an antiferromagnetic ordering at about 150–110 K, with ferromagnetic ordering components at lower temperature. The NTE in S-CRO is a result of a complex interplay among the spin, orbital, and lattice. [ABSTRACT FROM AUTHOR]

In recent years, upconversion (UC) luminescence has attracted considerable attention because of its potential application in temperature measurement. In this work, LaNbO4:Er3+/Yb3+ phosphors are synthesized using a solid-state method. The x-ray diffraction patterns show that the phosphors obtained exhibit a single monoclinic structure, and doping does not change the crystal structure. Intense green and red emissions are observed upon 980-nm excitation. The emission intensity varies with the doping concentration, and the best doping concentrations are 1 mol.% and 10 mol.% for Er3+ and Yb3+ ions, respectively. The possible luminescence mechanism is investigated based on the UC emission dependence on pump power. The temperature-sensing ability is also investigated based on the fluorescence intensity ratio between two thermally coupled levels 2H11/2 and 4S3/2. The maximum sensitivity achieved is 0.81% K−1 at around 430 K, suggesting that the phosphor is a potential candidate for temperature sensing applications. [ABSTRACT FROM AUTHOR]

A modified three-level laser kinetics model for a pulsed high-power optically pumped gas terahertz laser is introduced and used to model the lasing kinetics process of a gas terahertz laser system. We, for the first time to our knowledge, investigated the time evolution dynamics process of the pump intensity, population distribution among the energy levels, pump and THz signal gain coefficient, and the THz laser intensity within the pulsed D2O gas THz laser. High-power THz pulse with peak power of about 7.4 kW and pulse width of 145 ns at wavelength of 385 μm were obtained in the simulation, using an incident pump pulse with peak power of 2.2 MW and pulse width of 110 ns. THz pulse delay of 40 ns and pulse broadening of 35 ns were quantitatively analyzed. In addition, the experimental results for the pulse profile, pulse width, pulse broadening, pulse energy, and peak power are in agreement with the theoretical simulation results. [ABSTRACT FROM AUTHOR]

The nonmagnetic impurity effects on the triangular-lattice antiferromagnet (TLAF) Ba3Mn1−xZnxSb2O9 () by Zn2+ () dilutions are investigated based on magnetic susceptibility, specific heat and electron spin resonance (ESR) measurements. The ac susceptibility and specific heat result reveal that the two-dimensional (2D) antiferromagnetic (AFM) ground state is stable rather than forming a spin-glass (SG) phase for Zn2+ substitution up to , where the AFM transition temperature (TN) shifts slowly from 10.2 K () to 8.2 K (). For all samples, the divergence of the temperature-dependent linewidth of ESR can be well described in terms of the Berezinskii-Kosterlitz-Thouless (BKT) scenario. The evolution of ESR spectra suggests that the nonmagnetic impurity does not induce magnetic defects decoupled with AFM matrix but rather change the bulk AFM properties. [ABSTRACT FROM AUTHOR]

We report on the mid-infrared (MIR) and terahertz (THz) wave spectra of DO gas pumped using a fundamental transverse mode transversely excited atmospheric CO laser with an emission wavelength of 9.26 μm. We obtain MIR emission lines at center wavelengths of 9.262, 9.491, and 9.752 μm, which correspond to the vibrational-energy-level-transition lines of DO. We observe an intense THz stimulated Raman emission line of 385 μm and a weak cascade-transition line of 359 μm for transitions from rotational levels 4 to 4 and 4 to 4 in the first-excited vibration state of the DO molecule gas. We establish a four-energy-level system for modeling the laser kinetics of the dual-wavelength (385 and 359 μm) superradiation THz laser. For the optically pumped DO gas 385 μm THz laser, in considering the cavity effect and insertion loss of a THz cavity oscillator, an approximation treatment of the THz laser kinetics can be made based on a three-energy-level system. [ABSTRACT FROM AUTHOR]

A new laser kinetics model (LKM) of gas Terahertz (THz) laser has been improved and the output characteristics of a pulse gas 385 μm THz laser have been simulated and compared with the associated experimental data. Pump absorption coefficient (PAC) and pulse profile were determined using the experimental method, which provided reliable reference basis for approximated treatment of the model. The equations were solved numerically by the Runge-Kutta numerical method and some THz output characteristics, such as output power, pulse shape and pulse energy were theoretically investigated. The simulation and experimental results are in good agreement. [ABSTRACT FROM AUTHOR]

Inspired by mussel-adhesion phenomena in nature, a simple, mild surface modification process was elaborated to endow the polyurethane (PU) substrate with antibacterial/antifouling properties. In the present study, polydopamine was coated directly onto polyurethane surfaces. AgNO3 was then added and absorbed onto the surface by the active catechol and amine groups of the polydopamine coating. Meanwhile, the adsorbed Ag+ ions were reduced in situ into metallic silver nanoparticles by the 'bridge' of the polydopamine coating which yielded a coating with good antimicrobial properties. Finally, 1 H, 1 H, 2 H, 2 H-perfluorodecanethiol (CF3(CF2)7CH2CH2SH, F-SH) was attached on the PDA coating via the Michael addition reaction. The hydrophobic F-SH layer above the antibacterial layer yielded a surface with excellent antifouling properties. Preliminary antibacterial assays indicate that the coated surfaces show enhanced antibacterial activity against Escherichia coli (Gram-negative bacteria) and Staphylococcus aureus (Gram-positive bacteria). Platelet adhesion was significantly reduced for the F-SH-coated PU film. These results suggest that the modified PU could be used as an antibacterial material for future biomedical applications. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 531-538, 2017. [ABSTRACT FROM AUTHOR]

Temporal behavior of the pump pulses, residual pump pulses, and THz pulses for optically pumped DO gas molecules was investigated by using a tunable TEA CO laser as the pumping source. The pulse profiles of pump laser pulses, residual pump pulses, and the THz output pulses were measured, simultaneously, at several different gas pressures. For THz pulse, the pulse delay between the THz pulse and the pump pulse was observed and the delay time was observed to increase from 40 to 70 ns with an increase in gas pressure from 500 to 1700 Pa. Both THz pulse broadening and compression were observed, and the pulse broadening effect transformed to the compression effect with increasing the gas pressure. For the residual pump pulse, the full width at half maximum (FWHM) of the main pulse decreased with increasing gas pressure, and the main pulse disappeared at high gas pressures. The secondary pulses were observed at high gas pressure, and the time intervals of about 518 and 435 ns were observed between the THz output pulse and the secondary residual pump pulse at the pressure of 1400 Pa and 1700 Pa, from which the vibrational relaxation time constants of about 5.45 and 5.55 μs Torr were obtained. [ABSTRACT FROM AUTHOR]

Based on nominal components, SrCaBiTiNbO ( x = 0.25, 0.5, 0.75, 1) ceramics were prepared by means of solid-state reaction method. Their transition temperatures T can be experimentally tuned by controlling the atomic ratio of Sr/Ca. All the samples are demonstrated to exhibit relaxor ferroelectric property above room temperature, and T can be controlled effectively by changing the content of Sr ion in A1 site. In addition, the linear relation between T and the x corresponding to Sr ion of A1 site indicates that relaxor ferroelectric with wide-ranging transition temperatures can be obtained, catering for the potential applications. Meanwhile, the dielectric maximum temperature T of relaxation-I obeyed the Vogel-Fulcher law well, and Curie-Weiss fitting confirmed the displacive-type ferroelectric phase transition in these compounds. [ABSTRACT FROM AUTHOR]

It is well known that attentional capture by an irrelevant salient item is contingent on top-down feature selection, but whether attentional capture may be modulated by top-down spatial attention remains unclear. Here, we combined behavioral and ERP measurements to investigate the contribution of top-down spatial attention to attentional capture under modified spatial cueing paradigms. Each target stimulus was preceded by a peripheral circular cue array containing a spatially uninformative color singleton cue. We varied target sets but kept the cue array unchanged among different experimental conditions. When participants' task was to search for a colored letter in the target array that shared the same peripheral locations with the cue array, attentional capture by the peripheral color cue was reflected by both a behavioral spatial cueing effect and a cue-elicited N2pc component. When target arrays were presented more centrally, both the behavioral and N2pc effects were attenuated but still significant. The attenuated cue-elicited N2pc was found even when participants focused their attention on the fixed central location to identify a colored letter among an RSVP letter stream. By contrast, when participants were asked to identify an outlined or larger target, neither the behavioral spatial cueing effect nor the cue-elicited N2pc was observed, regardless of whether the target and cue arrays shared same locations or not. These results add to the evidence that attentional capture by salient stimuli is contingent upon feature-based task sets, and further indicate that top-down spatial attention is important but may not be necessary for contingent attentional capture. [ABSTRACT FROM AUTHOR]

Field experience makes a strong contribution to the learning of students. However, the procedure for conducting training sessions based on experiential teaching methods is relatively unclear, and the contents and aspects of students’ reflections during such training are not well known. This study applied experiential teaching methods in a college field experience course and investigated reflections on the experiences of 13 students. The content of students’ thoughts and other relevant data were analysed using Kolb’s experiential learning model. The students’ concepts formed during reflection might not immediately develop into the active experimentation process, indicating the challenges faced by students with the process of reflection during field experience. [ABSTRACT FROM PUBLISHER]

It remains ambiguous how college students form perceptions of professional development by identifying their emotional reactions and reflecting on their experiences in a situated setting. College students undergo professional development by participating in field experiences and reflecting on their experiential learning. In addition, researchers have increasingly insisted that student emotional reactions to learning should be addressed in higher education. Therefore, this qualitative study explored the emotional reactions of six college juniors and how they made sense of professional development, analyzing the contents of their reflective papers in a field experience course. The findings indicated that 10 types of emotional reactions caused students to form perceptions regarding professional development. The three major themes of these perceptions were acquiring and applying professional knowledge, the importance of self-understanding, and discovering professional attitudes. The study elucidates how college student awareness of emotional reactions could facilitate reflecting on experiential learning. [ABSTRACT FROM AUTHOR]

This article describes how a college social service learning centre at a Catholic university created an opportunity for researchers, college students and elementary school teachers to learn about meaning in life together, through a social service learning program in Taiwan. The participants’ involvement benefitted their learning, indicating that the meaning in life perceived by the younger generation has changed in response to the context of an evolving Chinese culture, and that participants constrained their callings by developing realistic plans consisting of goals emphasised in traditional Chinese culture. Challenges were identified: specifically, the participants’ callings did not directly reflect the lessons that they learned through involvement in the program, and implementing the service program as a one-time activity limited its effect on the participants’ ability to find meaning in life. Future development of the service program was discussed, based on the lessons learned through this action research. [ABSTRACT FROM AUTHOR]

Nontoxic lead-free multiferroic composites are synthesized by incorporating the dispersed 0.3CoFe2O4 (CFO) ferromagnetic nanoparticles into 0.7(K0.5Na0.5) NbO3-LiSbO3 (KNN-LS5.2) ferroelectric micromatrix. The multiferroicity of the composite can be verified by polarization-electric field hysteresis loop and magnetic hysteresis loop. The composite exhibits excellent magnetic properties. A dilution effect is observed in magnetic hysteresis loops. The field dependence of ME voltage coefficient is given as a function of magnetic field from -4 kOe to 4 kOe with a maximum magnetoelectric voltage coefficient of 10.7 mV⋅cm-1⋅Oe-1 at the frequency of 1 kHz. It is a very high value in the lead-free magnetoelectric composites system for the potential use on multifunctional devices. [ABSTRACT FROM AUTHOR]

Effect of bivalent cation Ca-doping on magnetic properties in multiferroic YMnO3 manganites was systemically studied by DC and AC magnetic measurements. Series of samples were prepared by solid-state reaction method with composition Y1− xCa xMnO3 ( x= i/8, i=2,3,...,7). The results show that each of the zero-field-cooling (ZFC) curves has a clear cusp and it shifts to higher temperature with increasing Ca-doping x. From the χ−1– T curve, the temperature of charge-ordering (CO) state TCO is given at about 244.0 K and this indicates that the CO state is dominated by the cooperative Jahn–Teller effect in Y1/2Ca1/2MnO3 with small A-site cation, for which there is a different behavior compared to the other manganites of larger 〈 r A〉. When x=2/8 and 7/8 for Y1− xCa xMnO3, the magnetization curve shows strong irreversibility between ZFC and FC data. The variation of AC susceptibility presents a maximum cusp at the beginning temperature of the bifurcation between ZFC and ZF curve and shifts to higher temperature with increasing measurement frequency for AC susceptibility. These results can be characterized by spin-glass, indicating that much more itinerant eg electrons are promoting the magnetic transition. [ABSTRACT FROM AUTHOR]

Power Internet of Things (IoT) is the application of IoT technology in the field of power grid, which can better control all kinds of power equipment, power personnel and operating environment. However, access to mass terminals brings higher requirements for terminal authentication and key management for the power IoT. And the traditional public key infrastructure (PKI) and identity-based public key cryptography (IB-PKC) exist the problems of certificate management and key escrow. Therefore, the paper proposes a novel authenticated key agreement scheme based on the certificateless public key cryptography (CL-PKC) mechanism. In addition, the proposed scheme is proven with the improved extended Canetti-Krawczyk (eCK) security model. Finally, the implementation of the authenticated key agreement protocol is given based on the actual application requirement of the power IoT, and the analysis and comparison of the simulation demonstrates that the proposed scheme has higher efficiency and would be suitable for the power IoT. [ABSTRACT FROM AUTHOR]

The rapid development of the power Internet of Things (IoT) has greatly enhanced the level of security, quality and efficiency in energy production, energy consumption, and related fields. However, it also puts forward higher requirements for the security and privacy of data. Ciphertext-policy attribute-based encryption (CP-ABE) is considered a suitable method to solve this issue and can implement fine-grained access control. However, its internal bilinear pairing operation is too expensive, which is not suitable for power IoT with limited computing resources. Hence, in this paper, a novel CP-ABE scheme based on elliptic curve cryptography (ECC) is proposed, which replaces the bilinear pairing operation with simple scalar multiplication and outsources most of the decryption work to edge devices. In addition, time and location attributes are combined in the proposed scheme, allowing the data users to access only within the range of time and locations set by the data owners to achieve a more fine-grained access control function. Simultaneously, the scheme uses multiple authorities to manage attributes, thereby solving the performance bottleneck of having a single authority. A performance analysis demonstrates that the proposed scheme is effective and suitable for power IoT. [ABSTRACT FROM AUTHOR]