Photomodulated cryogenic temperature sensing through a photochromic reaction in Na0.5Bi2.5Ta2O9: Er/Yb multicolour upconversion.

Optical temperature sensing of the non-thermally coupled energy levels (N-TCLs) based on fluorescence intensity ratio (FIR) technologies has excellent temperature sensitivity and signal recognition properties. In this study, a novel strategy is established to enhance the low-temperature sensing properties by controlling photochromic reaction process in Na0.5Bi2.5Ta2O9: Er/Yb samples. The maximum relative sensitivity reaches up to 5.99% K-1 at cryogenic temperature of 153 K. After irradiation with commercial laser of 405 nm for 30 s, the relative sensitivity is increased to 6.81% K-1. The improvement is verified to originate from the coupling of optical thermometric and photochromic behaviour at the elevated temperatures. The strategy may open up a new avenue to improve the thermometric sensitivity in photo-stimuli response photochromic materials.

Broadcasters' expertise and consumers' purchase intention: The roles of consumer trust and platform reputation.

Following the outbreak of COVID-19, farmer-assisted live streaming has become a hot topic in China. In this manuscript, we explore the ways in which broadcaster and platform characteristics jointly influence consumers' purchase intention. To examine our hypotheses, we distributed questionnaires to 261 Chinese consumers who viewed farmer-assisted live streaming. Correlational analyses, regression analyses, and confirmatory factor analyses were conducted to examine our hypotheses. The results show that broadcasters' expertise is positively related to consumer trust and that platform reputation moderates this relationship. In addition, consumer trust mediates the positive relationship between broadcasters' expertise and consumer purchase intention. Furthermore, the theoretical and practical implications of these findings are discussed.

Tunable Luminescence Contrast of Na0.5Bi4.5Ti4O15:Re (Re = Sm, Pr, Er) Photochromics by Controlling the Excitation Energy of Luminescent Centers.

High luminescent switching contrast of photochromic materials is extremely important in improving the sensitivity and resolution of optical switches and high-density optical data storage devices. To date, conventional methods, such as tuning absorption and emission bands based on electron or resonance energy transfer mechanisms in well-known organic photochromic molecules or compounds, have routinely been adopted to tune luminescent switching behavior. However, these strategies and mechanisms are not effectively applied to luminescence switching in inorganic materials because their crystal structures differ strongly from those of organic materials. In this paper, we report a new method to significantly tune the luminescent switching contrast by modifying the excitation energy of luminescent centers in a newly synthesized photochromism material: Na0.5Bi4.5Ti4O15:Re (Re = Sm, Pr, Er). A significant enhancement of luminescence switching contrast was achieved when the luminescent centers were excited by low energy photons at a given irradiation wavelength, intensity, and time, compared with high excitation energy photons. The trend "the lower the excitation energy, the higher the luminescence switching contrast" is universal in different rare earth ion-doped Na0.5Bi4.5Ti4O15 ferroelectrics. The changes in the luminescent switching contrast based on excitation energy are ascribed to nonradiative energy transfer from the luminescent center to the color center by dipole-dipole interactions according to Dexter theory. This possible utilization of excitation energy at lower energy levels is usually less destructive to both information recording and the recording material itself during luminescent readout processes while achieving higher luminescence switching contrast.

Dual-Mode Luminescence Modulation upon Visible-Light-Driven Photochromism with High Contrast for Inorganic Luminescence Ferroelectrics.

A luminescence ferroelectric oxide, Na(0.5)Bi(2.5)Nb2O9 (NBN), system with bismuth layer structure introduced by lanthanide ion (Er(3+)) has been demonstrated to exhibit reversible, high-contrast luminescence modulation (95%) and excellent fatigue resistance based on visible-light-driven photochromism (407 nm or sunlight). The coloration and decoloration process can be effectively read out by dual modes, upconversion and downshifting, and reversibly converted between green and dark gray by alternating visible light or sunlight irradiation and thermal stimulus. The luminescence modulation degree upon photochromic reactions is strongly dependent upon irradiation light wavelength and irradiation time. After undergoing several cycles, there are no significant degradations, showing high reversibility. Considering its high-contrast photoswitchable luminescence feature and intrinsic ferroelectricity of NBN host, NBN-based multifunctional materials can be suggested as a promising candidate for new potentials in photonic storage and optoelectronic multifunctional devices.

Reversible Luminescence Modulation upon Photochromic Reactions in Rare-Earth Doped Ferroelectric Oxides by in Situ Photoluminescence Spectroscopy.

Reversible luminescence photoswitching upon photochromic reactions with excellent reproducibility is achieved in a new inorganic luminescence material: Na(0.5)Bi(2.5)Nb2O9: Pr(3+) (NBN:Pr) ferroelectric oxides. Upon blue light (452 nm) or sunlight irradiation, the material exhibits a reversible photochromism (PC) performance between dark gray and green color by alternating visible light and thermal stimulus without inducing any structure changes and is accompanied by a red emission at 613 nm. The coloration and decoloration process can be quantitatively evaluated by in situ photoluminescence spectroscopy. Meanwhile, the luminescence emission intensity based on PC reactions is effectively tuned by changing irradiation time and excitation wavelength, and the degree of luminescence modulation has no significant degradation after several periods, showing very excellent reproducibility. On the basis of the luminescence modulation behavior, a double-exponential relaxation model is proposed, and a combined equation is adopted to well describe the luminescence response to light irradiation, being in agreement with the experimental data.

Reversible photoresponsive switching in Bi(2.5)Na(0.5)Nb(2)O(9)-based luminescent ferroelectrics.

Reversible luminescence modulation upon photochromic reactions with excellent reproducibility was achieved from Eu(3+) doped Bi2.5Na0.5Nb2O9 multifunctional ferroelectrics. The material exhibits strong sensitivity to visible light or sunlight with fast response time without inducing any structural changes.

Improving the Management of Appointment Registration and Exploring an Innovative Medical Service.

Improving levels of healthcare service to enhance patient care are not only what patients' demands of medical staff, but also what the medical staff demands of the hospital managers. The practical experiences of Xuzhou Central Hospital have proved that a carefully designed hospital culture helps to mobilize the enthusiasm of medical staff, improve patient satisfaction, and lead to an increase in the pace of a hospital's integrated development.

1,3-Dimethyl-5-(3-methyl-phen-oxy)-1H-pyrazole-4-carbaldehyde.

There are two independent mol-ecules in the asymmetric unit of the title compound, C(13)H(14)N(2)O(2), in which the dihedral angles between the substituted phenyl ring and the pyrazole ring are 86.5 (2) and 82.3 (3)°. The crystal packing features weak inter-molecular C-H⋯O inter-actions.

Reproductive isolation and pollination success of rewarding Galearis diantha and non-rewarding Ponerorchis chusua (Orchidaceae).

BACKGROUND AND AIMS: Increasing evidence challenges the conventional perception that orchids are the most distinct example of floral diversification due to floral or prezygotic isolation. Regarding the relationship between co-flowering plants, rewarding and non-rewarding orchids in particular, few studies have investigated whether non-rewarding plants affect the pollination success of rewarding plants. Here, floral isolation and mutual effects between the rewarding orchid Galearis diantha and the non-rewarding orchid Ponerorchis chusua were investigated. METHODS: Flowering phenological traits were monitored by noting the opening and wilting dates of the chosen individual plants. The pollinator pool and pollinator behaviour were assessed from field observations. Key morphological traits of the flowers and pollinators were measured directly in the field. Pollinator limitation and interspecific compatibility were evaluated by hand-pollination experiments. Fruit set was surveyed in monospecific and heterospecific plots. KEY RESULTS: The species had overlapping peak flowering periods. Pollinators of both species displayed a certain degree of constancy in visiting each species, but they also visited other flowers before landing on the focal orchids. A substantial difference in spur size between the species resulted in the deposition of pollen on different regions of the body of the shared pollinator. Hand-pollination experiments revealed that fruit set was strongly pollinator-limited in both species. No significant difference in fruit set was found between monospecific plots and heterospecific plots. CONCLUSIONS: A combination of mechanical isolation and incomplete ethological isolation eliminates the possibility of pollen transfer between the species. These results do not support either the facilitation or competition hypothesis regarding the effect of nearby rewarding flowers on non-rewarding plants. The absence of a significant effect of non-rewarding P. chusua on rewarding G. diantha can be ascribed to low levels of overlap between the pollinator pools of two species.

Isolation and characterization of 50 nuclear microsatellite markers for Cathaya argyrophylla, a Chinese endemic conifer.

PREMISE OF THE STUDY: Microsatellite primers were developed for the endangered Cathaya argyrophylla (Pinaceae) to investigate its genetic diversity and population genetic structure, as well as its evolutionary history. • METHODS AND RESULTS: Fifty dinucleotide microsatellite loci were identified in two populations. The number of alleles per locus ranged from 1 to 6, with a mean of 2.84. The observed and expected heterozygosities ranged from 0 to 0.889 and from 0 to 0.779, respectively. • CONCLUSIONS: These markers will facilitate further studies on the population genetics and evolutionary history of Cathaya argyrophylla.

Reproductive success of non-rewarding Cypripedium japonicum benefits from low spatial dispersion pattern and asynchronous flowering.

BACKGROUND AND AIMS: Outcrossing animal-pollinated plants, particularly non-rewarding species, often experience pollinator limitation to reproduction. Pollinator visitation is affected by various factors, and it is hypothesized that reproduction in non-rewarding plants would benefit from low spatial flower abundance and asynchronous flowering. In order to test this hypothesis, the influence of spatial pattern and flowering phenology on male and female reproductive success (RS) was investigated in a non-rewarding orchid, Cypripedium japonicum, in central China over two flowering seasons. METHODS: The probabilities of intrafloral self-pollination and geitonogamy caused by pollinator behaviours were estimated from field observations. Pollinator limitation was evaluated by hand-pollination experiments. RS was surveyed in different spatial flower dispersal patterns and local flower densities. The effects of flowering phenological traits on RS were assessed by univariate and multivariate regression analyses. KEY RESULTS: Hand-pollination experiments revealed that fruit production was strongly pollen limited throughout the entire reproductive season - over two seasons, 74.3 % of individuals set fruit following hand pollination, but only 5.2-7.7 % did so under natural conditions. Intrafloral self-pollination and geitonogamy within the potential clones might be rare. Both male and female fitness were substantially lower in clustered plants than in those growing singly. An increase in local conspecific flower density significantly and negatively influenced male RS, but had no effect on female RS. Phenotypic selection analysis indicated that individuals flowering earlier have the greatest probability of RS. Over 85 % of sampled flowering individuals had a flowering synchrony value >0.7; however, highly synchronous flowering was not advantageous for RS, as indicated by the negative directional selection differentials and gradients, and by the positive quadratic selection gradients. CONCLUSIONS: These results support the hypothesis that, as a consequence of density-dependent selection, low spatio-temporal flower abundance is advantageous for attracting pollinators and for reproduction in natural populations of non-rewarding C. japonicum.