A temperature sensor based on the enhanced upconversion luminescence of Li+ doped NaLuF4:Yb3+,Tm3+/Er3+ nano/microcrystals

In this paper, fluorescent and optical temperature sensing bi-functional Li⁺-doping NaLuF₄:Ln (Ln = Yb³⁺,Tm³⁺/Er³⁺) nanocrystals were synthesized via a simple hydrothermal method using oleic acid as a capping ligand.

Long persistent composite phosphor CaAl2O4:Eu2+,Nd3+/Y3Al5O12:Ce3+: a novel strategy to tune the colors of persistent luminescence

The design and characterization of a novel color tunable long persistent composite phosphor through radiative energy transfer.

Nanosized titanium dioxide resulted in the activation of TGF-β/Smads/p38MAPK pathway in renal inflammation and fibration of mice

Titanium dioxide nanoparticles (TiO2 NPs) have been demonstrated to damage the kidneys. However, whether chronic nephritis leads to renal fibration or the fibrosis is associated with the activation of TGF-β/Smads/p38MAPK pathway caused by TiO2 NPs exposure is not well understood. Forty male mice were separately exposed to 0, 2.5, 5, or 10 mg/kg body weight TiO2 NPs for 6 months. Renal biochemical functions and levels of TGF-β/Smads/p38MAPK pathway-related markers and extracellular matrix (ECM) expression in the kidneys were investigated. The findings showed that subchronic TiO2 NPs exposure increased levels of urinary creatisix (Cr), N-acetyl-glucosaminidase, and vanin-1, resulted in severe renal inflammation and fibration. Furthermore, TiO2 NP exposure upregulated expression of transforming growth factor-β1 (TGF-β1, 0.07- to 2.72-fold), Smad2 (0.42- to 1.63-fold), Smad3 (0.02- to 1.94-fold), ECM (0.15- to 2.75-fold), α-smooth muscle actin (0.14- to 3.06-fold), p38 mitogen-activated protein kinase (p38MAPK, 0.11- to 3.78-fold), and nuclear factor-κB (0.4- to 2.27-fold), and downregulated Smad7 (0.05- to 0.61-fold) expression in mouse kidney. Subchronic TiO2 NPs exposure induced changes of renal characteristics towards inflammation and fibration may be mediated via TGF-β/Smads/p38MAPK pathway, and the uses of TiO2 NPs should be carried out cautiously, especially in humans. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 1452-1461, 2016.

Enhanced optical temperature sensing and upconversion emissions based on the Mn2+ codoped NaGdF4:Yb3+,Ho3+ nanophosphor

In this study, to explore new phosphors for temperature sensing with high detection sensitivity, Yb³⁺/Ho³⁺/Mn²⁺ doped hexagonal NaGdF₄ nanoparticles were designed.

Emission in Gd6O5F8:Yb3+,Er3+ micro-particles for multimodal luminescence and temperature sensing upon 980 nm excitation

Mono-dispersed Gd₆O₅F₈:Yb³⁺/Er³⁺ micro-particles with different doping concentrations (Er³⁺: 0.1-1%) were synthesized by a facile hydrothermal route. The emission spectra, luminescent dynamic power-dependence and temperature sensing of up-conversion photoluminescence were investigated in detail. Under 980 nm excitation, the as-prepared samples exhibit intense red up-conversion and NIR emissions, which are influenced by the doping concentrations of Er³⁺ within Gd₆O₅F₈. With increasing concentrations of Er³⁺ ions, the visible up-conversion emissions first increase and then decrease, but NIR down-conversion emissions display a distinct trend, in which one peak at 1010 nm is highly suppressed and another at 1530 nm is increased quickly. Furthermore, the 980 nm excited optical temperature sensing property of the synthesized sample is realized over a wide temperature range by monitoring the intensity of up-conversion luminescence. The study provides a novel strategy based on lanthanide oxy-fluoride micro-particles for multifunctional displays, lighting and temperature sensing in a single system.

An upconversion luminescence and temperature sensor based on Yb3+/Er3+ co-doped GdSr2AlO5

GdSr₂AlO₅:Yb³⁺/Er³⁺ micro-particles were synthesized by a simple solid state method. The structure, morphology, size and upconversion luminescence features have been characterized. These results indicated that GdSr₂AlO₅ has a contracted tetragonal cell and has irregular block shaped particles with sizes of about 5 μm. During upconversion, green (²H_11/2, ⁴S_3/2 → ⁴I_15/2) (527 nm, 549 nm) and red (⁴F_9/2 → ⁴I_15/2) (665 nm) emissions had been observed, both of which occurred via a two-photon population process. In addition, green UC emission characteristics were studied, and it was found that its temperature ranged from 293 K to 473 K and the sensitivity was 0.0054 K⁻¹ at 473 K. This indicated that GdSr₂AlO₅:Yb³⁺/Er³⁺ micro-particles may have potential application in high temperature environments for safety signs.

GdSr₂AlO₅:Yb³⁺/Er³⁺ micro-particles were synthesized by a simple solid state method.

Synthesis and up-conversion luminescence of Yb3+/Er3+/Tm3+ doped Ca9Y(PO4)7

Samples of Ca₉Y(PO₄)₇ co-doped with Yb³⁺/Er³⁺, Yb³⁺/Tm³⁺, or Yb³⁺/Er³⁺/Tm³⁺ have been synthesized through two different routes, i.e. a modified hydrothermal method, followed by annealing in air at 850 °C and a solid-state reaction.

Crystal structure, photoluminescence and afterglow properties of red-emitting phosphors Ca4Nb2O9:Pr3+ for AC-LEDs

A novel Ca₄Nb₂O₉:Pr³⁺ short-afterglow phosphor exhibits efficient red emission under blue light excitation, which can be used to compensate the time gap of AC-LEDs.

Fabrication of selective interface of ZnO/CdS heterostructures for more efficient photocatalytic hydrogen evolution

Selective interface in ZnO/CdS heterostructure promote the photocatalytic activity.

Effect of Mn2+ on Upconversion Emission, Thermal Sensing and Optical Heater Behavior of Yb3+ - Er3+ Codoped NaGdF4 Nanophosphors

In thiswork, we investigate the influence of Mn2+ on the emission color, thermal sensing and optical heater behavior of NaGdF4: Yb/Er nanophosphors, which the nanoparticles were synthesized by a hydrothermal method using oleic acid as both a stabilizing and a chelating agent. The morphology and crystal size of upconversion nano particles (UCNPs) can be effectively controlled through the addition of Mn2+ dopant contents in NaGdF4: Yb/Er system. Moreover, an enhancement in overall UCL spectra of Mn2+ doped UCNPs for NaGdF4 host compared to the UCNPs is observed, which results from a closed back-energy transfer between Er3+ and Mn2+ ions (4S3/2 (Er3+) → 4T1 (Mn2+) → 4F9/2 (Er3+)). The temperature sensitivity of NaGdF4:Yb3+/Er3+ doping with Mn2+ based on thermally coupled levels (2H11/2 and 4S3/2) of Er3+ is similar to that particles without Mn2+ in the 303-548 K range. And the maximum sensitivity is 0.0043 K-1 at 523 K for NaGdF4:Yb3+/Er3+/Mn2+. Interestingly, the NaGdF4:Yb3+/Er3+/Mn2+ shows preferable optical heating behavior, which is reaching a large value of 50 K. These results indicate that inducing of Mn2+ ions in NaGdF4:Yb3+/Er3+ nanophosphors has potential in colorful display, temperature sensor.

The crystal structure and upconversion properties of Yb3+, Er3+/Ho3+ codoped BaLiF3 microcrystals with different morphologies

A series of x mol% Yb³⁺, 1 mol% Ho³⁺/1 mol% Er³⁺ (0 ≤ x ≤ 25) codoped BaLiF₃ microcrystals with different cubic morphologies and sizes (1.52 μm–3.83 μm) were synthesized by a facile surfactant-assisted hydrothermal-microemulsion approach for the first time.

[The effect of salvia miltiorrhiza and shengmai on inflammatory mediator and renal function of post-operative patients with obstructive jaundice]

OBJECTIVE

To investigate the effect of salvia miltiorrhiza and shengmai (SS) on inflammatory mediator and renal function in patients with obstructive jaundice (OJ).

METHODS

This study included three groups: the OJ patients receiving SS for 6 days after operation (the SS group, n = 15); the OJ patients not receiving SS (the OJ group, n = 15); the patients with other hepato-biliary disorders (the Non-OJ group, n = 15). The levels of ET, LPs, TNF-alpha, IL-6, IL-8 and urine RBP, TFR, ALB were measured one day before operation and 1, 4, 7 days after operation.

RESULTS

The SS group's LPs, TNF-alpha, IL-6, IL-8, ET, RBP, TFR and ALB levels were obviously lower on Day 7 after operation as compared with those on Day 1 after operation (P < 0.05). The urine RBP and ALB levels were significantly lower in the SS group than in the OJ group (P < 0.05).

CONCLUSION

The post-operative use of salvia miltiorrhiza and shengmai for patients with obstructive jaundice may effectively decrease the postoperative levels of plasma LPs, ET, TNF-alpha, IL-6 and IL-8. At the same time, salvia miltiorrhiza and shengmai may protect renal function by inhibiting inflammatory mediator and improving blood dynamics.

A super water-resistant MXene sponge flexible sensor for bifunctional sensing of physical and chemical stimuli

Flexible wearable sensors with multifunctional features have attracted great interest in various applications such as disease diagnosis, environmental detection and healthcare monitoring. However, it is still a challenge to achieve a multifunctional sensor with super water resistance without compromising the overall performance of the sensing material. Here, we developed a 3D bifunctional flexible sensor based on an MXene melamine sponge (MS) through a simple and effective ultrasonic mixing process and a further vacuum annealing process. The sensor is able to show excellent response to different stimuli, including pressure and humidity. The thermal annealing treatment allows MXene to adhere more firmly to the internal skeleton of the sponge, which does not easily fall off and improves the water resistance, thus achieving wearability and high sensitivity over a wide area. The T-MXene@MS sensor has a sensitivity of 9.97 kPa^-1 in the 5-15 kPa range, a fast response time (180 ms), and good stability at 4000 cycles, enabling accurate monitoring of human movement. The sensor has a rich porous structure while maintaining its inherent flexibility, which allows for long term testing of human respiration as well as the ability to respond quickly to dynamic changes in humidity, demonstrating excellent long-term stability for 40 days of humidity detection.

[Effects of transforming growth factor beta 1 on the expression of integrin beta 3 and the activity of focal adhesion kinase on human vascular endothelial cell]

OBJECTIVE

To observe the effects of transforming growth factors beta 1 (TGF beta 1) on the expression of integrin beta 3 and the activity of focal adhesion kinase (FAK).

METHODS

This study was performed on cultured human endothelial cells (EC) by using cell-ELISA and immunoprecipitation-tyrosine kinase assay respectively.

RESULTS

Under the stimulus of TGF beta 1, there a dose-dependent increase in the expression of integrin beta 3 chain in the surface of EC. And after the cultured EC were treated with 5 ng/ml or 10 ng/ml TGF beta 1 for 6 or 24 hours, the FAK activity in EC increased significantly as compared with the control group (P < 0.05).

CONCLUSION

The expression of integrin beta 3 and the activity of FAK on EC were regulated by TGF beta 1, and this regulation may be important in cell adherence, angiogenesis, and in the pathophysiology of atherosclerosis.

Highly efficient near-infrared solid solution phosphors with excellent thermal stability and tunable spectra for pc-LED light sources toward NIR spectroscopy applications

Near-infrared (NIR) luminescent materials have attracted wide research interest due to their unique photophysical properties for designing NIR light-emitting diodes (NIR LEDs). Here, a series of Cr3+-activated NIR-emitting solid solution phosphors, Gd1-xLux(Al1-xScx)3(BO3)4:0.01Cr3+ (GLASB:Cr3+) (x = 0 to 0.5), are successfully synthesized via a cosubstitution approach. The GLASB:Cr3+ phosphors reveal extraordinary optical performance with a desirable high IQE of 93.6%, considerable broadened FWHM (from 128 nm to 196 nm) and redshift of 119 nm (747 → 866 nm) as the amount of [Lu3+-Sc3+] ion doping increases. Moreover, their photoluminescent thermal stability is substantially improved, maintaining 105.7% of the initial integral intensity up to 150 °C, namely zero-thermal-quenching. The NIR pc-LED fabricated using the GLASB:Cr3+ phosphor generates an NIR output power of 46 mW and an electro-optical efficiency of 37% at a 120 mA input current. Finally, the characteristic NIR emission of this phosphor can not only be utilized in the fields of night-vision technology and biometric identification, but also exhibits a perfect match with the absorption of the bacteriochlorophyll (BChl) and light-harvesting protein (LHP) of photosynthetic bacteria (PSB), presenting a high application prospect for improving PSB photosynthesis.

Surfactants, polymers and their nanoparticles for personal care applications

A "touch me not" plant folding up rapidly upon being attacked or microbes depositing on teeth or ocean vessels even under hostile conditions are examples in nature that provide inspiration for developing new classes of personal care release or deposition systems. In this paper, development of such systems based on polymer/surfactant colloid chemistry is explored for achieving transport and release of cosmetic and pharmaceutical molecules at desired rates at desired sites. The successful development of products depends upon understanding and utilizing key interactions among surfactants, polymers and hybrid polymers that are relevant to personal care products. Thus, the absorbed layers or tethers on the particulates can be manipulated for desired dispersion of actives or depositions on substrate under any and all conditions. New hybrid polymers and nanogels have been synthesized for tuning up nanodomains that can extract and deliver at will cosmetics/drugs/toxins by perturbing pH, temperature or ionic strength of the system. Particularly, hydrophobically modified polymers have features of both polymers and surfactants and due to the associative nature of the hydrophobic groups, such polymers can form intramolecular nanodomains for performing carrier functions. Nanogels developed recently include that of polyacrylamide, poly(acrylic acid) and starch nanogels modified for extraction and subsequent slow release of fragrances and overdosed toxic drugs. Binding and release processes were investigated using surface plasmon resonance and fluorescence spectroscopies, powerful techniques for monitoring short term and long term changes.

[Observation of oral glucose-insulin releasing test in liver cirrhosis]

In order to investigate the disorders of carbohydrate metabolism and insulin secretion as well as their correlation in patients with liver cirrhosis, we performed an oral glucose tolerance test on 30 patients with liver cirrhosis proven by history, clinical findings, liver function test, radioisotope liver scanning, ultrasonic examination, gastroscopy, barium esophagogram and liver biopsy, compared with 20 healthy controls. Blood glucose and immunoreactive insulin were determined in both groups at 60 min intervals for 180 min. Results showed marked glucose intolerance with peak value 60 min after glucose load in cirrhotic patients with normal fasting blood glucose. Plasma IRI levels were significantly higher in cirrhotic patients than in normal subjects after glucose load (P less than 0.05), especially 180 min after (P less than 0.01). Twelve of 30 cases (40%) showed an abnormal OGTT curve. Of the 12 cases seven (23.3%) showed a diabetic OGTT curve, five (16.7%) an impaired OGTT curve. While eighteen of 30 cases (60%) showed an abnormal OGIRT curve. Among the 18 cases one (3.3%) presented hypersecretic OGIRT curve, twelve (40.0%) with delayed and prolonged peak, and five (16.7%) with hypersecretic OGIRT curve and delayed, prolonged peak.

The Upconversion Luminescence Properties of Er3+/Tm3+, Yb3+-Codoped Cubic BaLiF3

Cubic BaLiF3 samples were prepared using a facile surfactant-assisted hydrothermal-microemulsion method. The samples were characterized by X-ray Diffraction (XRD) and Scanning Electron Microscopy (SEM). The upconversion luminescence (UCL) properties of the Er3+/Tm3+, Yb3+- codoped BaLiF3 samples were measured under a 980 nm excitation wavelength. Moreover, the effects of varying the concentration of Li+ ions on the luminescence properties of Er3+, Yb3+ codoped BaLiF3 were also investigated. The Tm3+, Yb3+ codoped BaLiF3 samples displayed multi-color emissions. This behavior can be explained by the pump power dependence of the upconversion emissions and the energy levels diagram.

Excitation-dependent emission and highly efficient near-infrared luminescence in Cs2NaScCl6 double perovskite via Sb3+-Yb3+ alloying for multifunctional photoelectric applications

A novel Sb3+-Yb3+ co-doped Cs2NaScCl6 double perovskite with multimode luminescence and efficient excitation-dependent emission is proposed. Upon Sb3+-Yb3+ co-substitution in Cs2NaScCl6, NIR emission at 995 nm is greatly enhanced. A new STE emission peaking at 570 nm appears. Its great potential in anti-counterfeiting, LEDs and night vision is successfully demonstrated.