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Zinc tungstate is a semiconductor known for its favorable photocatalytic, photoluminescence, and scintillation properties, coupled with its relatively low cost, reduced toxicity, and high stability in biological and catalytic environments. In particular, zinc tungstate evinces scintillation properties, namely the ability to emit visible light upon absorption of energetic radiation such as x rays, which has led to applications not only as radiation detectors but also for biomedical applications involving the delivery of optical light to deep tissue, such as photodynamic therapy and optogenetics. Here, we report on the synthesis of zinc tungstate nanorods generated via an optimized but facile method, which allows for synthetic control over the aspect ratio of the as-synthesized anisotropic motifs via rational variation of the solution pH. We investigate the effect of aspect ratio on their resulting photoluminescent and radioluminescent properties. We further demonstrate the potential of these zinc tungstate nanorods for biomedical applications, such as photodynamic therapy for cancer treatment, by analyzing their toxicological profile within cell lines and neurons., (© 2024 Author(s). Published under an exclusive license by AIP Publishing.)

We report the seminal experimental isolation and DFT characterization of pristine [5,5] C 130 -D 5h (1) fullertubes. This achievement represents the largest soluble carbon molecule obtained in its pristine form. The [5,5] C 130 species is the highest aspect ratio fullertube purified to date and now surpasses the recent gigantic [5,5] C 120 -D 5d (1). In contrast to C 90 , C 100 , and C 120 fullertubes, the longer C 130 -D 5h has more nanotubular carbons (70) than end-cap fullerenyl atoms (60). Starting from 39,393 possible C 130 isolated pentagon rule (IPR) structures and after analyzing polarizability, retention time, and UV-vis spectra, these three layers of data remarkably predict a single candidate isomer and fullertube, [5,5] C 130 -D 5h (1). This structural assignment is augmented by atomic resolution STEM data showing distinctive and tubular "pill-like" structures with diameters and aspect ratios consistent with [5,5] C 130 -D 5h (1) fullertubes. The high selectivity of the aminopropanol reaction with spheroidal fullerenes permits facile separation and removal of fullertubes from soot extracts. Experimental analyses (HPLC retention time, UV-vis, and STEM) were synergistically used (with polarizability and DFT property calculations) to down select and confirm the C 130 fullertube structure. Achieving the isolation of a new [5,5] C 130 -D 5h fullertube opens the door to application development and fundamental studies of electron confinement, fluorescence, and metallic character for a fullertube series of molecules with systematic tubular elongation. This [5,5] fullertube family also invites comparative studies with single-walled carbon nanotubes (SWCNTs), nanohorns (SWCNHs), and fullerenes.

We have synthesized several morphologies and crystal structures of MgWO 4 using a one-pot hydrothermal method, producing not only monoclinic stars and large nanoparticles but also triclinic wool balls and sub-10 nm nanoparticles. Herein we describe the importance of reaction parameters in demonstrating morphology control of as-prepared MgWO 4 . Moreover, we correlate structure and composition with the resulting photoluminescence and radioluminescence properties. Specifically, triclinic-phase samples yielded a photoluminescence emission of 421 nm, whereas monoclinic-phase materials gave rise to an emission maximum of 515 nm. The corresponding radioluminescence data were characterized by a broad emission peak, located at 500 nm for all samples. Annealing the wool balls and sub-10 nm particles to transform the crystal structure from a triclinic to a monoclinic phase yielded a radioluminescence (RL) emission signal that was two orders of magnitude greater than that of their unannealed counterparts. Finally, to confirm the practical utility of these materials for biomedical applications, a series of sub-10 nm particles, including as-prepared and annealed samples, were functionalized with biocompatible PEG molecules, and subsequently were found to be readily taken up by various cell lines as well as primary cultured hippocampal neurons with low levels of toxicity, thereby highlighting for the first time the potential of this particular class of metal oxides as viable and readily generated platforms for a range of biomedical applications., (© 2022 The Authors.)

We report the first experimental characterization of isomerically pure and pristine C 120 fullertubes, [5,5] C 120 -D 5d (1) and [10,0] C 120 -D 5h (10766). These new molecules represent the highest aspect ratio fullertubes isolated to date; for example, the prior largest empty cage fullertube was [5,5] C 100 -D 5d (1). This increase of 20 carbon atoms represents a gigantic leap in comparison to three decades of C 60 -C 90 fullerene research. Moreover, the [10,0] C 120 -D 5d (10766) fullertube has an end-cap derived from C 80 -I h and is a new fullertube whose C 40 end-cap has not yet been isolated experimentally. Theoretical and experimental analyses of anisotropic polarizability and UV-vis assign C 120 isomer I as a [5,5] C 120 -D 5d (1) fullertube. C 120 isomer II matches a [10,0] C 120 -D 5h (10766) fullertube. These structural assignments are further supported by Raman data showing metallic character for [5,5] C 120 -D 5d (1) and nonmetallic character for C 120 -D 5h (10766). STM imaging reveals a tubular structure with an aspect ratio consistent with a [5,5] C 120 -D 5d (1) fullertube. With microgram quantities not amenable to crystallography, we demonstrate that DFT anisotropic polarizability, augmented by long-accepted experimental analyses (HPLC retention time, UV-vis, Raman, and STM) can be synergistically used (with DFT) to down select, predict, and assign C 120 fullertube candidate structures. From 10 774 mathematically possible IPR C 120 structures, this anisotropic polarizability paradigm is quite favorable to distinguish tubular structures from carbon soot. Identification of isomers I and II was surprisingly facile, i.e., two purified isomers for two possible structures of widely distinguishing features. These metallic and nonmetallic C 120 fullertube isomers open the door to both fundamental research and application development.

Ferroelectric domain walls are quasi-2D systems that show great promise for the development of nonvolatile memory, memristor technology, and electronic components with ultrasmall feature size. Electric fields, for example, can change the domain wall orientation relative to the spontaneous polarization and switch between resistive and conductive states, controlling the electrical current. Being embedded in a 3D material, however, the domain walls are not perfectly flat and can form networks, which leads to complex physical structures. In this work, the importance of the nanoscale structure for the emergent transport properties is demonstrated, studying electronic conduction in the 3D network of neutral and charged domain walls in ErMnO 3 . By combining tomographic microscopy techniques and finite element modeling, the contribution of domain walls within the bulk is clarified and the significance of curvature effects for the local conduction is shown down to the nanoscale. The findings provide insights into the propagation of electrical currents in domain wall networks, reveal additional degrees of freedom for their control, and provide quantitative guidelines for the design of domain-wall-based technology., (© 2022 The Authors. Advanced Materials published by Wiley-VCH GmbH.)

Dislocations are 1D topological defects with emergent electronic properties. Their low dimensionality and unique properties make them excellent candidates for innovative device concepts, ranging from dislocation-based neuromorphic memory to light emission from diodes. To date, dislocations are created in materials during synthesis via strain fields or flash sintering or retrospectively via deformation, for example, (nano)-indentation, limiting the technological possibilities. In this work, we demonstrate the creation of dislocations in the ferroelectric semiconductor Er(Mn,Ti)O 3 with nanoscale spatial precision using electric fields. By combining high-resolution imaging techniques and density functional theory calculations, direct images of the dislocations are collected, and their impact on the local electric transport behavior is studied. Our approach enables local property control via dislocations without the need for external macroscopic strain fields, expanding the application opportunities into the realm of electric-field-driven phenomena.

Utilizing quantum effects in complex oxides, such as magnetism, multiferroicity and superconductivity, requires atomic-level control of the material's structure and composition. In contrast, the continuous conductivity changes that enable artificial oxide-based synapses and multiconfigurational devices are driven by redox reactions and domain reconfigurations, which entail long-range ionic migration and changes in stoichiometry or structure. Although both concepts hold great technological potential, combined applications seem difficult due to the mutually exclusive requirements. Here we demonstrate a route to overcome this limitation by controlling the conductivity in the functional oxide hexagonal Er(Mn,Ti)O 3 by using conductive atomic force microscopy to generate electric-field induced anti-Frenkel defects, that is, charge-neutral interstitial-vacancy pairs. These defects are generated with nanoscale spatial precision to locally enhance the electronic hopping conductivity by orders of magnitude without disturbing the ferroelectric order. We explain the non-volatile effects using density functional theory and discuss its universality, suggesting an alternative dimension to functional oxides and the development of multifunctional devices for next-generation nanotechnology.

The goal of this article is to compare the geometrical structure of polytopes with 60 vertices, generated by the finite Coxeter group H 3 , i.e. an icosahedral group in three dimensions. The method of decorating a Coxeter-Dynkin diagram is used to easily read the structure of the reflection-generated polytopes. The decomposition of the vertices of the polytopes into a sum of orbits of subgroups of H 3 is given and presented as a `pancake structure'.

Diverse topological defects arise in hexagonal manganites, such as ferroelectric vortices, as well as neutral and charged domain walls. The topological defects are intriguing because their low symmetry enables unusual couplings between structural, charge, and spin degrees of freedom, holding great potential for novel types of functional 2D and 1D systems. Despite the considerable advances in analyzing the different topological defects in hexagonal manganites, the understanding of their key intrinsic properties is still rather limited and disconnected. In particular, a rapidly increasing number of structural variants is reported without clarifying their relation, leading to a zoo of seemingly unrelated topological textures. Here, we combine picometer-precise scanning-transmission-electron microscopy with Landau theory modeling to clarify the inner structure of topological defects in Er 1-x Zr x MnO 3 . By performing a comprehensive parametrization of the inner atomic defect structure, we demonstrate that one primary length scale drives the morphology of both vortices and domain walls. Our findings lead to a unifying general picture of this type of structural topological defects. We further derive novel fundamental and universal properties, such as unusual bound-charge distributions and electrostatics at the ferroelectric vortex cores with emergent U(1) symmetry.

This paper completes the series of three independent articles [Bodner et al. (2013). Acta Cryst. A69, 583-591, (2014), PLOS ONE, 10.1371/journal.pone.0084079] describing the breaking of icosahedral symmetry to subgroups generated by reflections in three-dimensional Euclidean space {\bb R}^3 as a mechanism of generating higher fullerenes from C60. The icosahedral symmetry of C60 can be seen as the junction of 17 orbits of a symmetric subgroup of order 4 of the icosahedral group of order 120. This subgroup is noted by A1 × A1, because it is isomorphic to the Weyl group of the semi-simple Lie algebra A1 × A1. Thirteen of the A1 × A1 orbits are rectangles and four are line segments. The orbits form a stack of parallel layers centered on the axis of C60 passing through the centers of two opposite edges between two hexagons on the surface of C60. These two edges are the only two line segment layers to appear on the surface shell. Among the 24 convex polytopes with shell formed by hexagons and 12 pentagons, having 84 vertices [Fowler & Manolopoulos (1992). Nature (London), 355, 428-430; Fowler & Manolopoulos (2007). An Atlas of Fullerenes. Dover Publications Inc.; Zhang et al. (1993). J. Chem. Phys. 98, 3095-3102], there are only two that can be identified with breaking of the H3 symmetry to A1 × A1. The remaining ones are just convex shells formed by regular hexagons and 12 pentagons without the involvement of the icosahedral symmetry.

The significance of sleep and factors that affect it have been well documented, however, in light of global climate change the effect of temperature on sleep patterns has only recently gained attention. Unlike many mammals, bats (order: Chiroptera) are nocturnal and little is known about their sleep and the effects of ambient temperature (Ta) on their sleep. Consequently we investigated seasonal temperature effects on sleep behaviour and surface body temperature of free-ranging Wahlberg's epauletted fruit bat, Epomophorus wahlbergi, at a tree roost. Sleep behaviours of E. wahlbergi were recorded, including: sleep duration and sleep incidences (i.e. one eye open and both eyes closed). Sleep differed significantly across all the individuals in terms of sleep duration and sleep incidences. Individuals generally spent more time awake than sleeping. The percentage of each day bats spent asleep was significantly higher during winter (27.6%), compared with summer (15.6%). In summer, 20.7% of the sleeping bats used one eye open sleep, and this is possibly the first evidence of one-eye-sleep in non-marine mammals. Sleep duration decreased with extreme heat as bats spent significantly more time trying to cool by licking their fur, spreading their wings and panting. Skin temperatures of E. wahlbergi were significantly higher when Ta was ≥35°C and no bats slept at these high temperatures. Consequently extremely hot days negatively impact roosting fruit bats, as they were forced to be awake to cool themselves. This has implications for these bats given predicted climate change scenarios.

The present research was undertaken to evaluate some biological parameters in rats fed with a supplemented diet with Opuntia ficus indica powder seeds. Feed intake and body weight of rats were measured every two days during nine weeks of treatment. Digestibility, feed conversion efficiency and protein efficiency ratio were determined. No difference in digestibility was noticed between the different diets. The results indicated a significant decrease in body weight of rats receiving a diet partially substituted with O. ficus indica powder seeds, probably due to a significant decrease in serum-free thyroxin (FT(4)) compared to the control group. In the treated group, a decrease of glucose concentration in blood and an increase of glycogen in liver and skeletal muscle were noticed. A significant increase in HDL-cholesterol was noted in the group receiving the supplemented diet with O. ficus indica powder seeds. These results suggest that O. ficus indica seeds can be used as a healthy food.

Cactus pear (Opuntia ficus indica) is native to Tunisia and the fruit is consumed exclusively as fresh fruit. The seed oil is rich in polyunsaturated fatty acids but the nutritive value of the oil is unknown. The objective of our research was to determine the fatty acid content of cactus pear seed oil and to evaluate the effect of an oil supplemented diet on rats. The main fatty acids of prickly pear seed oil were C16:0, C18:0, C18:1, C18:2 with an exceptional level of linoleic acid, up to 700 g kg(-1), and a total content of unsaturated fatty acids of 884.8 g kg(-1). Feed intake and body weight of rats were measured every two days during the nine weeks of treatment. Digestibility, feed conversion efficiency and protein efficiency ratio were determined. No difference in digestibility was noted for the oil enriched diet. The results indicated a significant decrease in serum glucose concentration (22%) over the control group. However, an increase in the concentration of glycogen was noted in liver and muscle. Blood cholesterol and low density lipoprotein (LDL)-cholesterol decreased in the treated group. High density lipoprotein (HDL)-cholesterol concentration remained unaltered during the treatment. These findings support the nutritional value of cactus pear as a natural source of edible oil containing essential fatty acids and reinforce the possibility of cactus pear as a new crop for Tunisia especially in semi-arid regions, where conventional crops are difficult to establish.

Background: Although the physical and psychological effects of decreased mobility have been documented, little is known about what it means to be mobile from the institutionalized elders' perspective. Even less is known about nurses' perceptions regarding institutionalized elders' mobility and about mobility enhancing strategies., Aim: The purpose of this study was to generate knowledge about the phenomenon of mobility from both the nurses' and institutionalized elders' perspective., Design: An exploratory qualitative design was used. Focus groups with residents and nursing staff were conducted in three long-term care facilities in a large metropolitan city in 1998. Ethical approval was received from the ethics committees in all three facilities prior to study implementation. Twenty long-term care facility residents and 15 nursing staff participated in the study., Methods: A trained facilitator used an interview guide to moderate discussions in which residents' and nurses' opinions and feelings about mobility were solicited. The group responses were tape recorded, transcribed and coded. The codes reflected major concepts or abstractions of the data and emerged from the participants' verbal responses to the research questions., Findings: Both groups identified mobility as being pivotal to the residents' quality of life and well-being. The residents viewed mobility as a means of freedom, choice and independence, and they made great efforts to maintain their mobility. The nurses also valued the importance of mobility and assisted the residents through preparatory care, environmental modifications and encouragement. Factors that related to the residents' willingness to be mobile, environmental barriers and the impact of waiting were compared between the two groups., Conclusion: Mobility involves more than the movement from one point to another. The nature of the assistive nurse-client relationship and the resident's subjective perspective must become central to understanding the meaning of mobility for residents in a long-term care facility.

An innovative program in ethics education exists at Baycrest Centre for Geriatric Care. This program can serve as a helpful model for long-term care and geriatric care facilities seeking to implement formal training programs in bioethics. Various aspects of the ethics education program are examined. In addition to describing the role of the ethics committee and research ethics board, consideration is given to case consultations, ethics rounds, the training of junior physicians and medical students, grand rounds and the planning of conferences and guest lectures. With regard to educational content in bioethics, health law, professional guidelines and the principlist approach of Beauchamp and Childress are used to explore the ethical dimensions of particular cases. Given the clinical context of the educational initiatives, the pedagogical approach is predominately case-based. While the bioethics literature emphasizes the patient-physician relationship, ethics education at Baycrest recognizes the importance of multiple professions. Physicians, nurses, social workers, speech pathologists, nutritionists and other health care providers are involved in ethical deliberation and education.

The previous single radial haemolysis method is simplified for complement activity assay in human serums. The proceeding a "one point" test is described. This new technique is remarkable by its simplicity and rapidity. A study of the precision shows tha possibility of to make use of this simple "one point" hemolytic plate method.

The hemolytic activity of human complement is evaluated after diffusion in agarose containing sensitized erythrocytes. The results show a linear relation between hemolysis area and logarithm of concentration.

The experimental conditions for single radial haemolysis are analysed in order to optimize the haemolytic plate method for the assay of human total complement. The amount of haemolytic antibody used for sensitization of red cells, the concentration of sensitized sheep erythrocytes, the thickness of agarose layer, and the diameters of wells all exercise an influence on the area of haemolysis. The effects of these parameters are investigated with a view to obtaining the clearest reading and greatest sensitivity of the haemolytic activity plate method, and at the same time verifying the validity of the assay and the precision of the human serum haemolytic titres. This work reports the optimal experimental requirements with regard to the factors studied for minimizing the sources of error in complement haemolytic plate assay.

The dilution of serum and the ionic components having an usual effect upon the lithium assay is examined about their influences in the determination of lithium microquantities. These are discussed according to the technique selected as well as the normal ionic variations that may be come across in serums. The method was applied to determination of serum lithium rate in a group of old subjects. The got lithium distribution is unsymmetrical at lower rates and no influence of age or sex was obvious.