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The introduction of DNA logic circuits endows smart down/upconversion nanomachines with “AND” logically activated and enzyme-free amplified photodynamic therapy.

This paper focuses on the use of [Zn2+–Ge4+] to co-replace [Ga3+–Ga3+], which redshifts the near-infrared emission of Cr3+ in Ga2O3, and broadens the full width at half maximum.

The Gram-staining negative, oxidase and catalase negative strain KC-ST17

Aims This study aimed to isolate and identify entomopathogenic fungi (EPF) from fungus-infected Ostrinia furnacalis larvae, screen their bio-efficacy against O. furnacalis, and select the most suitable virulent native EPF for biocontrol agent development. Methods and Results The occurrence of EPF isolated from various maize production regions in Xinjiang was investigated. Of 13,864 O. furnacalis cadavers surveyed, 536 were selected, and of 136 fungal specimens collected, 14 species were identified. Four fungal isolates were highly pathogenic to O. furnacalis: Aspergillus sp., Lecanicillium attenuatum, Beauveria bassiana and Penicillium polonicum. The Aspergillus sp. was the most abundant (42.25% distribution frequency). Bioassay results revealed that it was as pathogenic as B. bassiana (positive control), with 96.58% lethality against O. furnacalis (LC50: 1.40 × 104 conidia ml−1, LT50: 3.41 days). Through morphological examination and rDNA-benA and rDNA-CaM homogeneity analyses, the isolate was identified as Aspergillus nomius. Conclusions Four EPF species were highly pathogenic, with A. nomius being the most prevalent in Xinjiang. A. nomius is a potential biocontrol agent. Significance and Impact of Study For sustainable prevention and control of O. furnacalis infestation, identifying biocontrol agents with high virulence against O. furnacalis is crucial. The findings of this study support the development of EPF-based biocontrol approaches.

A novel bacterial strain, TLK-CK17

Polychromatic emission can be achieved by controlling the distribution of the rare earth activator in multi-cation lattices, which can be used in the fields of white light LED and fluorescence temperature sensing.

Here, a "chemical unit co-substitution" method is used to improve the near-infrared (NIR) emission of phosphors, using [Zn

Slow intermolecular collisions and "always active" responses compromise the amplification efficiency and response accuracy of nonenzymatic hybridization chain reaction (HCR). In this study, a photoactivatable membrane-oriented HCR (MOHCR) system was rationally designed by binding a photocleavable initiator probe onto a target protein and then anchoring cholesterol-modified hairpin-structure fuel probes. When irradiated, the bound initiator probe was photoactivated and initiated self-assembly to generate activatable and amplified imaging. In a proof-of-concept assay, breast-cancer-derived exosomes were imaged based on the surface protein epithelial cell adhesion molecule (EpCAM). Photoactivatable responses provided precise spatiotemporal control of the MOHCR, and fluidic membranes enabled accelerated reaction kinetics. Our MOHCR system demonstrated high efficiency and accuracy in differentiating between plasma samples from breast cancer patients and healthy donors.

A novel non-contact optical thermometer, qualified with high sensitivity and temperature resolution, is urgently needed for temperature measuring of micro devices, moving objects and specific severe environments. Hence, a series of dual-emitting La5Si2BO13:Ce3+,Eu2+ phosphors were synthesized. The two ions show diverse responses with the changing in temperature. The variational emissions of Ce3+ and Eu2+ can be converted to FIR (fluorescence intensity ratio) signals. The maximal absolute sensitivity Sa and relative sensitivity Sr reach up to 0.07526%/K and 3.2241%/K, respectively. It is worthy noting that the Sa and Sr possess the same variation tendency and both have high values in the low temperature region (293–373 K), showing the great temperature measuring property especially in low temperature region. The temperature sensing characteristics are superior to the results of most previous reports. The energy transfer (ET) process is certified to occur from Ce3+ to Eu2+ ions. These studies indicate that La5Si2BO13: Ce3+,Eu2+ phosphor could have a good prospect for optical thermometry.

A series of BaGd2O4:Bi3+,Eu3+ phosphors with dual-emitting centers were prepared by high-temperature solid-state method. X-ray diffraction (XRD), scanning electron microscope (SEM), energy dispersive spectroscopy (EDS), fluorescence spectroscopy, lifetime decay curve and variable temperature emission spectroscopy were used to systematically study the structure, luminescence performance and temperature characteristics. Under ultraviolet (UV) excitation, the BaGd2O4:Bi3+,Eu3+ phosphor showed a broad-band emission in the blue region corresponding to transitions of Bi3+ ions and the sharp red light emission corresponding to Eu3+ ions. The Bi3+ and Eu3+ ion emission peaks were well-separated, which meets a prerequisite for efficient temperature signal resolution measurement. The fluorescence intensity ratio (FIR) technique was used to measure the different temperature response characteristics between Bi3+ blue emission and Eu3+ red emission. When the temperature varies from 293 K to 473 K, the relative temperature sensitivity (Sr) of BaGd2O4:Bi3+,Eu3+ phosphors is obtained, was determined as 1.0182%K−1. In addition to calculating the relative sensitivity by FIR technology, we can also obtain the value of Sr through experiments and formulas related to the decay life, and found to be 1.0651%K−1. Therefore, BaGd2O4: Bi3+,Eu3+ phosphor is an excellent non-contact optical temperature measurement material.

Eu2+/Sm3+ co-doped dual-emitting Sr4La(PO4)3O phosphors were synthesized through a convenient high temperature solid state reaction in reductive atmosphere. The structure, luminescence, energy transfer and temperature-dependent luminescence properties of Eu2+/Sm3+ co-doped Sr4La(PO4)3O phosphors were researched and analyzed in detail. The blue emission of Eu2+ and the red emission of Sm3+ can work together as FIR signals. Based on the different response characteristics of these two ion emissions to temperature, Sr4La(PO4)3O:Eu2+/Sm3+ phosphor achieves the relative sensitivity of 0.48384%/K and a wide range of temperature measurements from room temperature to 573 K. The results reveal that the Sr4La(PO4)3O:Eu2+/Sm3+ phosphor has application prospect in the field of high temperature optical thermometry. The energy transfer mechanism is proved to be the dipole-dipole interaction between Eu2+ and Sm3+ ions.

The goal of this work was to explore the potential effects of bacteria inoculation on the lignocellulose degradation and the underlying microbial mechanism during cow dung composting. The results suggested that bacteria inoculation better-accelerated temperature rose and increased thermophilic phase. Compared to the control (without inoculation, CK), the cellulose, hemicellulose, and lignin degradation rates of treated group (EG) increased from 53.3% to 70.0%, 50.2% to 61.3% and 46.4% to 60.0%, respectively. The microbial community structure and diversity were obviously changed by inoculation. Moreover, inoculation contributed to modulate the key compost microbial functional populations linking to the degradation of lignocelluloses by stamp analysis. Correlation matrix analysis indicated that the expression of bacterial lingo-cellulolytic enzymes were closely related to the key microbial functional populations. Overall, the results confirmed the importance of bacteria inoculation and have important implication for promoting the efficiency and quality of cow dung compost.

The ongoing COVID‐19 pandemic constitutes a new challenge for public health. Prevention and control of infection have become urgent and serious issues. To meet the clinical demand for higher accuracy of COVID‐19 detection, the development of fast and efficient methods represents an important step. The most common methods of COVID‐19 diagnosis, relying on real‐time fluorescent quantitative PCR(RT‐qPCR), computed tomography, and new‐generation sequencing technologies, have a series of advantages, especially for early diagnosis and screening. In addition, joint efforts of researchers all over the world have led to the development of other rapid detection methods with high sensitivity, ease of use, cost‐effectiveness, or allowing multiplex analysis based on technologies such as dPCR, ELISA, fluorescence immunochromatography assay, and the microfluidic detection chip method. The main goal of this review was to provide a critical discussion on the development and application of these different analytical methods, which based on etiology, serology, and molecular biology, as well as to compare their respective advantages and disadvantages. In addition to these methods, hematology and biochemistry, as well as auxiliary analysis based on pathological anatomy, ultrasonography, and cytokine detection, will help understand COVID‐19 pathogenesis. Together, these technologies may promote and open new windows to unravel issues surrounding symptomatic and asymptomatic COVID‐19 infections and improve clinical strategies toward reducing mortality., The main goal of this review was to provide a critical discussion on the development and application of these different analytical methods, which based on etiology, serology, molecular biology, as well as to compare their respective advantages and disadvantages. In addition to these methods, hematology and biochemistry, as well as auxiliary analysis based on pathological anatomy, ultrasonography, and cytokine detection, will help understand COVID‐19 pathogenesis.

Aerobic composting is an efficient and environmentally friendly method of converting organic waste into nontoxic fertilizers or soil quality enhancers. The quality of the resultant compost depends greatly upon the composition of the substrate used. The initial carbon-to-nitrogen (C/N) ratio of the substrate is an important factor affecting the composting process. This study elucidated how initial C/N ratios affect the biodegradation of lignocellulose, due to changes in microbial community structure. Four different C/N ratios (20:1, 25:1, 30:1, and 35:1) were examined during a 35-day composting process. The degradation of cellulose, hemicellulose, and lignin was highest (35.7%, 30.6%, and 19.1% respectively) at a 30:1 C/N ratio; after 30 days, the 25:1 C/N ratio ranked second in terms of lignocellulosic degradation rate. The 30:1 C/N ratio further promoted the growth of functional microorganisms responsible for lignocellulose degradation (Luteimonas, Sphingobium, Trichoderma, Chaetomium, and Rosellinia), while the growth of dominant pathogenic microbes (Erwinia and Ulocladium) decreased significantly. These results confirm that the initial C/N ratio of the substrate has a significant effect on the microbial community and degradation of organic matter, during walnut branch composting. This process could therefore offer an alternative means of efficient recycling and recovery of waste branches.

A series of the BaGd2O4:Bi3+, Sm3+ phosphors with dual emission centers were prepared by high-temperature solid-phase method. X-ray diffraction, scanning electron microscopy, energy dispersive spectroscopy, fluorescence spectroscopy, lifetime decay curve, and variable temperature emission spectroscopy were used to systematically study the structure, luminescence performance, and temperature characteristics of the samples. At ultraviolet stimulation, BaGd2O4:Bi3+, Sm3+ phosphors exhibit broad band blue emission, corresponding to the transition of Bi3+ from 3P1 level to 1S0 level, and sharp red characteristic emission, corresponding to the Sm3+ ions’ energy level transition from 4G5/2 to 6Hm/2(m=5,7,9). In addition, the Bi3+ and Sm3+ ions’ emission positions in BaGd2O4 host are ideally separated. Based on the property, FIR can be employed to test the difference of temperature in response to performances between Bi3+ blue light emission and Sm3+ red light emission. For the Bi3+/Sm3+ co-doped system, it is found that their relative sensitivity gradually decreases with the increase of the Sm3+ ion concentration, the value of maximum can reach 1.105%K-1, which makes it possible to synthesize temperature sensing materials with adjustable sensitivity. The relative sensitivity can also be calculated by experiments related to the decay lifetime, and the value of maximum obtained was 1.662%K-1. Thus, BaGd2O4:Bi3+, Sm3+ systems are superior non-contact optical pyrometer materials with ultrahigh temperature sensitivity and superhigh signal discriminability.

A series of Ca2-xSrxMgSi2O7: Ce3+, Eu2+ (x = 0, 0.5, 1, 1.5, 2) phosphors were synthesized on the basis of high temperature solid-state reaction strategy. Its phase composition, optical spectral properties, fluorescence lifetime and temperature sensitivity were investigated in detail. Under excitation at 342 nm, the emission spectra of Ca2MgSi2O7: Ce3+, Eu2+ exhibit a purple emission band (Ce3+ ions) and a green emission band (Eu2+ ions). The emission band of Ce3+ overlaps with the excitation band of Eu2+, indicating that there may be energy transfer (ET) between the two ions. The decreasing fluorescence lifetime of Ce3+ with increasing Eu2+ concentration further proves the existent of ET process in Ca2MgSi2O7: Ce3+, Eu2+ phosphor. In addition, Ca2-xSrxMgSi2O7: Ce3+, Eu2+ solid solution was designed and synthesized by Sr2+ substituting Ca2+. As Sr2+ gradually replaced Ca2+, the blue-shift of Ce3+ and Eu2+emission band were caused by the change of crystal field. With the increase of temperature, the fluorescence intensity of Ce3+ and Eu2+ emission bands decreased slowly and rapidly, respectively. Hence, in the Ce3+/Eu2+ co-activated Ca2-xSrxMgSi2O7 phosphor, Ce3+ ions and Eu2+ ions can be used as fluorescence intensity ratio (FIR) signals. The maximum relative sensitivity can reach 2.43% K−1 (at 293 K) under 342 nm excitation. The above results indicate that Ca2-xSrxMgSi2O7: Ce3+, Eu2+ phosphors are potential candidates for optical thermometer materials.

In order to study the optical temperature sensing characteristics of phosphors with dual emission centers, a series of La2MgGeO6: Bi3+, Mn4+ phosphors were prepared by solid phase method at high temperature. Due to the different thermal responses of Bi3+ and Mn4+ ions, the fluorescence intensity ratio between the double emission centers is expected to be an effective method for temperature sensing. The structural phase and luminescence properties of the samples were characterized by X-ray powder diffraction, field emission scanning electron microscopy, ultraviolet spectrophotometer and fluorescence spectrometer. According to the structure of La2MgGeO6 host, it can be seen that Bi3+ ion can replace La3+ ion and Mn4+ ion can replace Ge4+ ion because the valence state of ions are the same and the ion radius is close. Through the excitation of ultraviolet light, La2MgGeO6: Bi3+, Mn4+ present two emission bands, which correspond to the Bi3+ ions 3P1 → 1S0 transition (emitting blue light) and Mn4+ ions 2Eg → 4A2g transition (emitting red light) respectively. Moreover, there is energy transfer from Bi3+ ions to Mn4+ ions. Based on the different temperature responses of Bi3+ blue emission and Mn4+ red emission, their fluorescence intensity ratio was used to discuss the temperature measurement characteristics. The absolute sensitivity and relative sensitivity of La2MgGeO6: Bi3+, Mn4+ phosphors reached the maximum value of 1.419% K−1 at 473 K and 3.027% K−1 at 383 K in the temperature range of 293–473 K. Therefore, La2MgGeO6: Bi3+, Mn4+ phosphors are excellent materials for optical temperature measurement.

Developing a new temperature sensing material with high temperature sensitivity and resolution is crucial in optical thermometry. Therefore, a series of dual-emitting Eu2+/Eu3+ co-doped NaZr2(PO4)3 phosphors were prepared in the air atmosphere. Eu3+ ions successfully replaced Na+ and were partially reduced to Eu2+. Then, the K+ ions were introduced to replace Na+ ions, which affected the luminescence and thermostability of Eu2+ and Eu3+. The reducing mechanism and the effect of Eu doping concentration on the Eu3+/Eu2+ reduction ratio were discussed in detail. Using different responses of Eu2+ and Eu3+ to the changing temperature, the FIR (fluorescence intensity ratio) signals were detected to measure temperature (293–413 K). The K+ ions influence the crystalline field and energy level structure, thereby decreasing the thermal stability of Eu2+ and enhancing that of Eu3+, resulting in the improvement of Sa and Sr to 0.026 K−1 and 3.84% K−1, respectively. Its temperature sensitivity is higher than that of many other reported inorganic materials, demonstrating that the NaZr2(PO4)3: K+, Eu phosphors have a good application prospect in optical thermometry.

In this paper, Ca2MgSi2O7: Bi3+, Eu3+ thermometric phosphors with dual-emitting centers were favorably designed. Phosphors were created by the approach of solid phase in high temperature condition. The inner phase structure and photoluminescence characteristics were investigated. The approaches of characterization including X-ray diffractometry, SEM, EDS mapping, ultraviolet–visible diffuse reflectance spectroscopy, as well as fluorescence spectrometry were applied. The influence of temperature on the photoluminescence characteristics of Ca2MgSi2O7: Bi3+, Eu3+ phosphors was systematically researched. The intensity ratio of 3P1→1S0 purple luminescence of Bi3+ and 5D0→7F2 red luminescence of Eu3+ is dependent on the temperature, which provides a method of optical sensing thermometry. Under the UV excitation of 287 nm, the maximum relative sensitivity (Sr) of this Ca2MgSi2O7: Bi3+, Eu3+ phosphor is 0.66%K−1 (at 533 K) and absolute sensitivity (Sa) gets to 0.0086 K−1 (at 573 K). The experimental phenomena were explained by the thermal-quenching mechanism. The garnered results provide an idea for the future development of luminescence intensity ratio (LIR) technology sensing materials on the basis of Ca2MgSi2O7.