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Mutational signatures are somatic mutation patterns enriching operational mutational processes, which can provide abundant information about the mechanism of cancer. However, understanding of the pathogenic biological processes is still limited, such as the association between mutational signatures and genes.We developed a simple and practical R package called RNMF (https://github.com/zhenzhang-li/RNMF) for mutational signature analysis, including a key model of cumulative contribution abundance (CCA), which was designed to highlight the association between mutational signatures and genes and then applying it to a meta-analysis of 1073 individuals with esophageal squamous cell carcinoma (ESCC).We revealed a number of known and previously undescribed SBS or ID signatures, and we found that APOBEC signatures (SBS2* and SBS13*) were closely associated with PIK3CA mutation, especially the E545k mutation. Furthermore, we found that age signature is closely related to the frequent mutation of TP53, of which R342* is highlighted due to strongly linked to age signature. In addition, the CCA matrix image data of genes in the signatures New, SBS3*, and SBS17b* were helpful for the preliminary evaluation of shortened survival outcome. These results can be extended to estimate the distribution of mutations or features, and study the potential impact of clinical factors.In a word, RNMF can successfully achieve the correlation analysis of mutational signatures and genes, proving a strong theoretical basis for the study of mutational processes during tumor development.

Blue light-excitable Cs4PbBr6@CsPbBr3 solids with a near unity PLQY, strong stability, and low photoluminescence deterioration are encapsulated into a laser-driven LCD device.

Materials exhibiting luminescent switching upon photochromic reaction have received increasing attention due to their potential applications in erasable optical storage. Nevertheless, it is still challenging to synthesize photochromic materials that selectively absorb different wavelengths of light for erasable optical storage. Herein, we report a series of fluorophosphate structure (Ca,Sr,Ba)5(PO4)3F:Eu2+ photochromic materials with tunable absorption bands upon photochromic reaction. Tunable photochromism is a phenomenon is rarely observed in inorganic materials. Thus, to fill this gap, we designed (Ca,Sr,Ba)5(PO4)3F:Eu2+ photochromic materials with highly reversible tunable photochromism by adjusting and substituting the alkaline-earth metal. The substitution of the divalent cations with a smaller ionic radius by larger cations induced a shift in the absorption band of the (Ca,Sr,Ba)5(PO4)3F:Eu2+ photochromic material to a longer wavelength. The multicolor change may pave the way for the design of photochromic materials to meet specific application requirements. All as-prepared photochromic flexible films showed excellent fatigue resistance, water resistance, flexibility and stretchability. Writing, erasing, and reading were performed using the flexible photochromic films, demonstrating their particular application in complicated environments for optical storage and rewritable flexible devices. An efficient energy transfer process was established between luminescent and photochromic units, which may open a door for the design of high-performance optical storage materials. Erasable optical storage could be excited by UV and visible light to encode and decode on the flexible film.

Non-lead metal halide double perovskites (MHDPs), recognized as one of the most promising alternatives to lead-based metal halide perovskites (MHPs), have received enormous attention in recent years due to their nontoxicity and good thermodynamic stability. However, the development of a broadband near-infrared (NIR) emitting MHP with high optical efficiency and robust chemical stability remains a challenge. In this work, we report a broadband NIR emitting lead-free MHDP Cs2SnCl4Br2 activated by Sb3+ with the largest full width at half maximum of 164 nm. The morphology and particle size were controllably evolved via finely adjusting the preparation temperature. Most surprising is that the high-temperature post-treatment, which is to be avoided always, was applied for the as-obtained NIR MHDP, achieving an unexpectedly great boosting of the NIR emission efficiency by 13 times. Moreover, excellent stability was achieved, which showed that the broadband NIR emission intensity retains 90% of the initial level after continuous UV irradiation for 48 h, maintains 100% of the initial level after being immersed in water for 6 h, and increases up to 102% after being stored in air for 2 months. The origin of NIR emission from Sb3+ ionoluminescence was verified with the combination of experimental and DFT studies. As a proof-of-concept, a broadband NIR light emitting diode with a radiant flux of 17.23 mW was fabricated using the as-obtained broadband NIR MHDP for NIR spectroscopy applications. This work not only provides a method for the rational design of broadband NIR MHPs and extending their applications, but also prompts the steps to develop novel MHDPs with superior chemical and optical stability.

Reversible photoluminescence switching based on photochromism has drawn considerable interest due to its widespread promising applications in photo-switching, anti-counterfeiting and optical information storage. In this paper, we reported a novel photochromic material Sr6Ca4(PO4)6F2:Eu2+ which exhibits the reversible photoluminescence switching ability. Coloration and bleaching, which are attributed to the capture and release of electrons by traps, respectively, can be efficiently converted accompanied by the color change between pink and white upon alternating UV light irradiation and visible light irradiation or thermal treatment. Sr6Ca4(PO4)6F2:Eu2+ shows photochromic properties such as high reversibility and excellent fatigue resistance. Trap engineering allows an effective way to modify the traps through changing the Eu2+ doping content and co-dopant Ln3+ (La, Y, Gd, Lu) ions, thereby purposely controlling the performance of photochromism. Photoluminescence switching strongly depends on the photochromic effect and exhibits a good reversibility after several cycles of measurements. The relative photoluminescence intensity measured from a partially thermal bleaching state indicates the highest instantaneous temperature suffered by the sample, indicating the good application prospects in instantaneous temperature recording. In addition, various patterns can be repeatedly recorded in the photochromic material Sr6Ca4(PO4)6F2:Eu2+ by alternative UV light and visible light/heat treatment, demonstrating potential application in erasable optical data storage.

Trivalent terbium-doped oxycarbonate (La2O2CO3:1%Tb3+) one-dimensional nanorods are synthesized via a facile precipitation method. The average length of La2O2CO3:1%Tb3+ nanorods is 184.5 nm. Doping Tb3+ ions led to several visible emission peaks at 486 nm, 542 nm, and 587 nm under excitation of 258 nm wavelength light. The green afterglow at 542 nm can be detected almost 600 s after ceasing the UV-light irradiation. It can be calculated that the La2O2CO3:1%Tb3+ sample has one shallow trap depth (E = 0.848 eV) by measuring the thermoluminescence. All the results indicate that a simple precipitation method can synthesize a one-dimensional nanorod with green persistent luminescence.

Mutational signatures can reveal the mechanism of tumorigenesis. We developed theRNMFsoftware for mutational signatures analysis, including a key model of cumulative contribution abundance (CCA) which was designed to highlight the association between genes and mutational signatures. Applied it to 1073 esophageal squamous cell carcinoma (ESCC) and found that APOBEC signatures (SBS2* and SBS13*) mediated the occurrence ofPIK3CAE545k mutation. Furthermore, we found that age signature is strongly linked to theTP53R342* mutation. In addition, the CCA matrix image data of genes in the signatures New, SBS3* and SBS17b* were helpful for the preliminary evaluation of shortened survival outcome. In a word,RNMFcan successfully achieve the correlation analysis of genes and mutational signatures, proving a strong theoretical basis for the study of tumor occurrence and development mechanism and clinical adjuvant medicine.

Tb3+ is a typical green emitting luminescence center in inorganic compounds. However, the absorption of Tb3+ is very weak in ultraviolet spectral region (from 240 to 400 nm). Ce3+ is often used as a sensitizer to transfer energy to Tb3+. In this paper, Ce3+ and Tb3+ were co-doped into a novel aluminates-borates LaAl2.03B4O10.54. Ce3+ can absorb UV light (from 240 to 340 nm) and transfer absorbed energy to co-doped Tb3+ effectively and bring bright green emission of Tb3+. The crystal structure and fluorescence spectra of phosphors, the efficiency of energy transfer between Ce3+ and Tb3+, decay dynamics, the thermal stability and internal quantum efficiency of luminescence have been investigated in detail. These results indicate that the color tunable LaAl2.03B4O10.54: Ce3+, Tb3+ phosphor is a potential green-emitting material. Especially, analysis about the relationship of the doping concentration of luminescence centers and thermal stability of luminescence points out a feasible way to enhance the thermal stability of luminescence in the future.

A novel thermometer, qualified with miniaturization, real-time monitoring, non-invasion, remote-control, and high spatio-temporal resolution, is urgently required for temperaturedetecting of sub-micrometric objects and in specific harsh conditions. Herein, we report an adaptable dual-mode optical thermometry platform LiTaO3:Ti4+, Eu3+@PDMS. A proof-of-concept implementation based on fluorescence thermometer (FT) demonstrates outstanding temperature sensing performance with excellent reversibility. The maximum Sa and Sr are as high as 0.671 and 5.425% K−1, respectively, with minimal temperature resolution of 0.14 K. Whilst, the maximum Sa and Sr based on lifetime thermometer (LT) are determined to be 0.122 and 3.637% K−1, respectively, with superior temperature resolution of 0.027–0.058 K. Finally, flexible phosphor films and 3D micro-rod arrays with handily encrypted information are fabricated for the unclonable multi-modal/multi-dimensional anti-counterfeiting application by exploiting light, temperature and time-domains as the “key” to decrypt the “locked” ciphertext, which indicates the promising prospect in temperature sensing and anti-counterfeiting. This work not only paves a way for developing novel spatial/temporal dual-mode real-time thermometer based on synergetic luminescence of lanthanide (Ln) and transition-metal (TM) ions with high temperature sensitivity and resolution, but also opens a new “window” for extending the thermometer as a flexible device in advanced multi-mode multi-dimensional high-level secure anti-counterfeiting.

High brightness and precise adjustment of luminescence colour of phosphors are two main targets in the research of phosphor-converted white LEDs. However, few feasible strategy can be employed to achieve the multicolor-tunable luminescence under the premise of maintaining high quantum efficiency. Here, we demonstrate a high-efficiency energy-transfer process from Tb3+ to Eu3+ ions with a higher luminescent quantum efficiency (64.5% and 53.4%, respectively), and green-red multicolor emission in Lu2GeO5 host via varying the doping content of Tb3+ and Eu3+ ions. Besides, Lu2GeO5:Tb3+, Lu2GeO5: Eu3+ and Lu2GeO5: Tb3+, Eu3+ all exhibit weak thermal quenching which ensures the stable use of white LED device in the high temperature environment. This paper provides a novel multicolor-tunable phosphor with high brightness, efficient energy transfer and weak thermal quenching, which presents a potential application for UV-converted white LEDs.

This paper demonstrates that a highly thermal stable and tunable-luminescence phosphors Y3Al2Ga3O12: Tb3+, Eu3+ with efficient energy transfer, which is prepared by the high-temperature solid-state reaction. First-principles method is performed to analyze the electronic structures, band structure, density of states and formation energy of Y3Al2Ga3O12: Tb3+, Eu3+. For high luminescence output, Y3-xAl2Ga3O12: xTb3+ and Y3-yAl2Ga3O12: yEu3+ with high concentration quenching (x = 0.5 and y = 0.7) are achieved. The effect of energy transfer from Tb3+ to Eu3+on emission color tuning and luminescence thermal stability is studied. The energy transfer efficiency from Tb3+ to Eu3+ reaches as high as 74.2% and emission color can be tuned from green, yellow and red by adjusting the ratio of Tb3+/Eu3+. What's more, Y3Al2Ga3O12: Tb3+, Eu3+ phosphor exhibits a good thermal stability, of which emission intensity still keeps 60% at 150 °C.

Highly thermo-stable and tunable-luminescence phosphors Y3Al2Ga3O12: Tb3+, Sm3+ are synthesized by conventional solid-state reaction method. In this study, the multicolor emission, thermal stability and energy transfer mechanism in Y3Al2Ga3O12: Tb3+, Sm3+ are evaluated in detail. The emission color can be tuned from green to yellow by adjusting the Tb3+/Sm3+ ratio. The energy transfer efficiency from Tb3+ to Sm3+ reaches as high level as 62.5%. Energy transfer mechanism of Tb3+-Sm3+ are related to the dipole–dipole interaction. Furthermore, Y3Al2Ga3O12: Tb3+, Sm3+ phosphor shows a good thermal stability, the integrated intensity (150 °C) of YAGO: 0.5 Tb3+, 0.1Sm3+ still keeps more than half of that at room temperature. Therefore, the multicolor tunable phosphor Y3Al2Ga3O12: Tb3+, Sm3+ presents a potential for application in the white LEDs.

Luminescent material Ca2Ba3(PO4)3F:Eu2+ displays green emitting in the range of 400–700 nm, which is ascribed to the 4f65d1 →4f7 transition of Eu2+ ions. Amazingly, the body color of the samples can be changed between colorless and green upon alternative UV and visible light irradiation/heating treatment with robust fatigue resistance due to photochromism. The photochromic effect strongly depends on the Eu2+ doping concentration. After remote-controlled short-UV irradiation, the overall Eu2+ emission intensity presents a significant decrease, and inversely, exhibits an increase to the initial level after illuminated by longer wavelength light or heat treatment. Moreover, the fluorescence lifetime also can be regulated reversibly, of which the regulation degree depends on the short-UV irradiation and longer wavelength illumination time/heating temperature. A schematic diagram based on energy levels is proposed to illustrate the photochromism mechanism.

Early detection and appropriate medical treatment are of great use for ear disease. However, a new diagnostic strategy is necessary for the absence of experts and relatively low diagnostic accuracy, in which deep learning plays an important role. This paper puts forward a mechanic learning model which uses abundant otoscope image data gained in clinical cases to achieve an automatic diagnosis of ear diseases in real time. A total of 20,542 endoscopic images were employed to train nine common deep convolution neural networks. According to the characteristics of the eardrum and external auditory canal, eight kinds of ear diseases were classified, involving the majority of ear diseases, such as normal, Cholestestoma of the middle ear, Chronic suppurative otitis media, External auditory cana bleeding, Impacted cerumen, Otomycosis external, Secretory otitis media, Tympanic membrane calcification. After we evaluate these optimization schemes, two best performance models are selected to combine the ensemble classifiers with real-time automatic classification. Based on accuracy and training time, we choose a transferring learning model based on DensNet-BC169 and DensNet-BC1615, getting a result that each model has obvious improvement by using these two ensemble classifiers, and has an average accuracy of 95.59%. Considering the dependence of classifier performance on data size in transfer learning, we evaluate the high accuracy of the current model that can be attributed to large databases. Current studies are unparalleled regarding disease diversity and diagnostic precision. The real-time classifier trains the data under different acquisition conditions, which is suitable for real cases. According to this study, in the clinical case, the deep learning model is of great use in the early detection and remedy of ear diseases.

Trivalent terbium-doped oxycarbonate (La

Recently, downconversion materials have attracted considerable research due to large promotion of the efficiency of silicon-based solar cells through the absorption of solar radiation via quantum cutting. However, due to lack of ideal downconversion material, it is emergent to seek novel downconversion phosphors with large ultraviolet absorption and high quantum efficiency. Herein, we reported the photoluminescence performance and dynamics of a downconversion phosphor La2GeO5: Bi3+, Nd3+. This phosphor presents a strong ultraviolet absorption and emits a series of intense near infrared emissions by quantum cutting. The emission energy from the Nd3+ matches the energy gap of silicon-based solar cells which can improve the solar cell efficiency. Energy transfer from Bi3+ to Nd3+ in La2GeO5 occurs, proving that energy transfer mechanism of Bi3+→Nd3+ is an electric dipole-dipole (DMSO‑d6) interaction. The energy transfer efficiency of Bi3+→Nd3+ and theoretical quantum efficiency for La2GeO5: Bi3+, Nd3+ are calculated to be as high as 91% and 191%, respectively. La1.92GeO5:0.03Bi3+, 0.05Nd3+ phosphor presents a promising thermal behavior with an activation energy of 0.152 eV. Thus, the development of near-infrared downconversion Bi3+, Nd3+ co-doped phosphors might open up a new approach to achieve high efficiency silicon solar cells by means of quantum cutting.

In the past decades, a great variety of single-phase white-emitting phosphors have been developed, however most them can't satisfy us due to their low quantum efficiency and poor thermal stability. Herein, we reported a promising candidate of a white-emitting La2(GeO4)O:Bi3+/Eu3+ phosphor, exhibiting an efficient energy transfer, good thermal stability and high quantum efficiency. Rietveld structure refinement of La2(GeO4)O:Bi3+ was performed to confirm Bi3+ occupation of La sites in La2(GeO4)O. An analysis on the red-shift of both excitation and emission spectra of La2(GeO4)O:Bi3+ was made by combining the crystal structure and their spectroscopy. Thermal quenching temperature (T50%) of La2(GeO4)O:Bi3+ was approximately 532 K which is higher than that (473 K) of the LED chips under high power current driving and La2(GeO4)O:Bi3+ presented a spectral blue-shift as an increase in temperature. Furthermore, thermal quenching of La2(GeO4)O:Bi3+ was explained in detail by the configurational coordinate. More importantly, single Bi3+ doped La2(GeO4)O presented a blue-greenish broad band at 480 nm with a high quantum efficiency (48%) and excellent thermal stability (ΔE = 0.353 eV). Energy transfer from Bi3+ to Eu3+ in La2(GeO4)O efficiently occurred and energy transfer mechanism of Bi3+→Eu3+ was demonstrated to be dipole-quadrupole interaction. By codoping Eu3+ in La2(GeO4)O:Bi3+, La2(GeO4)O:Bi3+, Eu3+ phosphor exhibited the blue-green and red dual emissions. Fortunately, a single-phase white-emitting phosphor La1.94(GeO4)O:0.03Bi3+, 0.03Eu3+ was obtained with excellent resistance against thermal quenching and a quantum efficiency of 37%.

Here, we report a series of Eu3+-doped Sr3SnMO7 (M = Sn, Si, Ge, Ti, Zr, or Hf) phosphors, which exhibited both photochromism and luminescence switching. Under alternating UV (254 nm) light irradiation and visible light/thermal stimulus, the obtained samples showed a reversible color change from the initial white color to brown. Based on photochromism and red luminescence, the red emission could be effectively modulated. Most interestingly, the Eu3+ red emission could be reversibly modulated by alternating UV and visible light/thermal treatment with excellent reproducibility, which can be used as non-destructive optical information write-in and read-out. In the case of the Sr3SnMO7 host, the band gap could be clearly changed from 3.64 to 4.41 eV through partial cation substitution, resulting in an evident effect on the photochromism and photoluminescence modulation performance. This provides a new method for tuning the photochromism and photoluminescence modulation properties. These results suggest that Sr3SnMO7:Eu3+ phosphors with photochromism and luminescence switching properties constitute a class of promising candidates for the development of optical data storage devices. On the basis of their luminescence modulation behavior, a model with non-radiative energy transfer from the luminescent centers to the color center was developed.

First-principles calculations and experiment analysis were performed to study the internal relation between seven types of intrinsic defects and the persistent luminescence in SrZrO3 host material. The calculation shows that rich zirconium defects have the low energy cost and thus are easy to form. Zr vacancies are too high energy to play any role in defect which is related luminescence phenomenon of SrZrO3 phosphor. However, oxygen vacancies stand out as a likely candidate, because it can yield two carrier reservoirs: a fully-occupied singlet electron's reservoir which lies above the valence band maximum, and an empty triply degenerate hole's reservoir which is just below the conduction band minimum. Sr vacancies are not directly relevant to the persistent luminescence due to its too shallow electron trap level. The characteristics of these defects are fully explained by the equilibrium properties of SrZrO3. An experimental study of the thermoluminescence glow for these defects is conducted and the calculation is consistent with the experimental results. A mechanism of the persistent luminescence for SrZrO3:Pr3+, Eu3+ is explained according to oxygen vacancies trap center. Findings of this study may serve as theoretical references for controlling intrinsic traps by more refined experiments.

Here, we report a novel long-persistent luminescence (LPL) phosphor, Ba2SiO4:Eu2+,Ho3+. The crystal structure, photoluminescence, photoluminescence excitation and LPL decay behaviors were studied systematically. The developed LPL phosphor Ba2SiO4:Eu2+,Ho3+ shows super-LPL, which remains above 2.97 mcd m−2 even 24 h after the removal of UV irradiation source. The outstanding LPL performance is mainly derived from the tailoring of trap distribution via Ho3+ co-doping. 15 days after UV irradiation, the sample still shows observable green luminescence by 980 nm stimulation. By means of photostimulated luminescence (PSL), excitation duration, decay duration and excitation temperature dependent thermoluminescence spectra, the continuous trap distribution, trap distribution modulation and dynamics of electron motion are characterized. The role of co-dopant Ho3+ serving as electron traps and the tailoring of trap distribution are revealed. The fabrication of Ba2SiO4:Eu2+,Ho3+ phosphor film allows optical information write-in after passing UV light through a photomask (projection printing method) and then the stored information is read out by thermal stimulation or 980 nm photostimulation, which holds great promise for optical information storage. Moreover, combined with the experimental and DFT calculation results, a tentative schematic diagram is proposed for the illustration of LPL and PSL mechanism in Ba2SiO4:Eu2+,Ho3+.

In this work, we report a bifunctional phosphor Sr 3 Sn 2 O 7 :Eu 3+ which shows red luminescence and photochromism properties. All as-prepared Sr 3 Sn 2 O 7 :Eu 3+ samples were studied systematically by X-ray diffraction, photoluminescence spectra, diffuse reflection spectra, thermoluminescence glow curves. The optimum doping concentration of Eu 3+ for the PL emission was determined to be 0.2. Concentration quenching and thermal quenching in photoluminescence (PL) emission were discussed in detail. Meanwhile, the material can change its surface color from white to brown under ultraviolet (UV) (254 nm) irradiation. The colored sample is bleached by blue light (400 nm) irradiation or heat treatment. The coloration-bleaching process is reversible, which makes it potential to be used in the field of photo switchers, erasable optional memory medial and sensors. Finally, a model is proposed on the basis of experimental results to discuss the mechanism of photoluminescence and photochromism in Sr 3 Sn 2 O 7 :Eu 3+ in detail.

The XGboost and LightGBM algorithm performs predictive analysis of sales volume in the product sales data set. The principle of XGboost and LightGBM algorithm is studied, the predicted objects and conditions are fully analyzed, and the algorithm parameters and data set characteristics are compared. The results show that n_estimators have a small effect on the prediction of model XGboost, while gamma has a large effect on the prediction of model XGboost. Learning_rate has a small impact on LightGBM prediction, while n_estimators have a large impact on LightGBM prediction. Finally, the optimal parameters were obtained, and the sales volume from January to October 2015 was predicted based on the optimal parameters, and RMSE values of the two algorithms were obtained. Statistical analysis shows that there is no significant difference between the two algorithms in the optimal prediction results after adjusting their own parameters.

Previous research has shown that interactions between melamine molecules within a cluster can give rise to the molecular self-assembly and that the spectral characteristic of melamine can be used to inspect melamine in a carrier. Although the structural and spectral characteristics of an isolated single melamine molecule and the molecular arrays on metal or semiconductor surfaces have been studied extensively, little is known about that of isolated multimolecular melamine clusters. In this work, density functional theory (DFT) calculations at the ω-B97XD/6-311++G(d,p) level were performed to study the structural and spectral characteristics of isolated melamine clusters [C3N3(NH2)3]n (n = 1-4) in the ground state. The calculation shows that a ground-state single melamine molecule takes a quasi-planar structure. The C and N atoms of the molecule are in one plane, which we call the molecular plane, while the H atoms deviate slightly from the molecular plane. When melamine molecules gather to form a cluster, the intermolecular hydrogen bonds (IHBs) N-H···N will arise, with the lengths of H···N in the range from 1.960 to 1.970 Å; the length of N-H will be elongated to 1.022 Å from its original of 1.004 Å, the N-H···N bond angles will be about 176°, and the average single-bond binding energy will be approximately -0.285 eV. In a multimolecular cluster, each melamine molecule still takes the quasi-planar structure. Each molecular plane in the cluster retains a planar structure, and some H atoms diverge more from their molecular planes. The molecular planes in a cluster are not coplanar, and the dihedral angle between the molecular planes of two neighboring melamine molecules ranges from 38 to 40°. In addition, the theoretical study of the infrared (IR) spectrum and nuclear magnetic resonance (NMR) spectrum of [C3N3(NH2)3]n (n = 1-4) was conducted. The results confirm the existence of IHBs in a multimolecular melamine cluster and reveal the symmetry of the electron cloud distribution in the melamine clusters. Experimental study of the IR for solid-state melamine and (13)C NMR spectra for both solid- and liquid-state melamine samples were also carried out, in which the corresponding spectral characteristics of [C3N3(NH2)3]n (n = 2-4) clusters deduced from theoretical study were observed. Findings of this study may serve as theoretical references for future identification and utilization of melamine clusters.