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Single-walled carbon nanotube (SWCNT)/Bi2Te3 composite powders were fabricated via a one-step in situ reductive method, and their corresponding bulk composites were prepared by a cold-pressing combing pressureless sintering process or a hot-pressing process. The influences of the preparation methods on the thermoelectric properties of the SWCNT/Bi2Te3 bulk composites were investigated. All the bulk composites showed negative Seebeck coefficients, indicating n-type conduction. A maximum power factor of 891.6 μWm−1K−2 at 340 K was achieved for the SWCNT/Bi2Te3 bulk composites with 0.5 wt % SWCNTs prepared by a hot-pressing process, which was ~5 times higher than that of the bulk composites (167.7 μWm−1K−2 at 300 K) prepared by a cold-pressing combing pressureless sintering process, and ~23 times higher than that of the bulk composites (38.6 μWm−1K−2 at 300 K) prepared by a cold-pressing process, mainly due to the enhanced density of the hot-pressed bulk composites. [ABSTRACT FROM AUTHOR]

A series of LiNbO3 crystals doped with various MgO concentrations (0, 3%, and 5 mol%) was simultaneously grown in one furnace by the modified vertical Bridgman method. The wet chemistry method was used to prepare the polycrystalline powders, and the growth conditions were optimized. The full width at half maximum of high-resolution X-ray rocking curves for (001) reflection of 5 mol% Mg doped lithium niobate (LN) crystal was about 8″, which meant it possessed high crystalline quality. The OH− absorption spectra shifted to 3534.7 cm−1, and the UV absorption edge violet shift indicated that 5 mol% MgO successfully doped in LN and exceeded the threshold. The extraordinary refractive index gradient of 5 mol% Mg doped LN crystal was as small as 2.5 × 10−5/cm, which exhibited high optical homogeneity. [ABSTRACT FROM AUTHOR]

Abstract: Large size lanthanum trifluoride (LaF3) single crystals doped with Eu2+ and Ca2+ have been grown by the Bridgman–Stockbarger method. Fluoridization of raw materials was carried out by heating commercial reagent LaF3 at above 1000 °C for 10 h with a flow of HF gas in a resistance furnace. Due to lack of EuF2, EuF3 was reduced with Si in vacuum or nitrogen atmosphere at about 900 °C for 2 h. Cracking was considerably reduced by optimizing the growth conditions, such as a small growth rate of 2–3 mm/h and a [001]-oriented seed. LaF3 single crystal up to 50 mm in diameter and 40 mm in length was obtained. [Copyright &y& Elsevier]

Fast and accurate identification of microbial pathogens is critical for the proper treatment of infections. Traditional culture‐based diagnosis in clinics is increasingly supplemented by metagenomic next‐generation‐sequencing (mNGS). Here, RNA/cDNA‐targeted sequencing (meta‐transcriptomics using NGS (mtNGS)) is established to reduce the host nucleotide percentage in clinic samples and by combining with Oxford Nanopore Technology (ONT) platforms (meta‐transcriptomics using third‐generation sequencing, mtTGS) to improve the sequencing time. It shows that mtNGS improves the ratio of microbial reads, facilitates bacterial identification using multiple‐strategies, and discovers fungi, viruses, and antibiotic resistance genes, and displaying agreement with clinical findings. Furthermore, longer reads in mtTGS lead to additional improvement in pathogen identification and also accelerate the clinical diagnosis. Additionally, primary tests utilizing direct‐RNA sequencing and targeted sequencing of ONT show that ONT displays important potential but must be further developed. This study presents the potential of RNA‐targeted pathogen identification in clinical samples, especially when combined with the newest developments in ONT. [ABSTRACT FROM AUTHOR]

Samarium-doped La3Nb0.5Ga5.5O14 (Sm:LGN) crystals were grown along a (100)-orientation by the Bridgman method for quasi-parametric chirped pulse amplification (QPCPA) applications. The structure of La1-xSxmGN (x = 0.1, 0.2) crystals was the same as that of La3Nb0.5Ga5.5O14 (LGN) crystals. The effective segregation coefficient of Sm3+ in the La0.9Sm0.1GN crystal was 0.140. The full width at half maximum (FWHM) of La1-xSxmGN (x = 0.1,0.2) crystals was lower than 50″, which indicated the high quality of the crystals. The density of the La0.9Sm0.1GN crystal was 5.968 g/cm3 and that of the La0.8Sm0.2GNcrystal was 5.988 g/cm3. The transmittance of the crystals at 532nm and 800nm was all above 73%. The absorption spectra indicated that the crystals had strong absorption peaks at wavelengths of 1544 and 1595 nm. The thermal properties of La1-xSxmGN (x = 0.1, 0.2) crystals were similar to those of the LGN crystals. The laser damage thresholds of La0.9Sm0.1GN and La0.8Sm0.2GN crystals were, respectively, 188.30 and 54.84 TW/cm2 (@800 nm,35 fs). [ABSTRACT FROM AUTHOR]

Strand-selection is the final step of microRNA biogenesis in which functional mature miRNAs are generated from one or both arms of precursor. The preference of strand-selection is diverse during development and tissue formation, however, its pathological effect is still unknown. Here we find that two miRNA arms from the same precursor, miR-574-5p and miR-574-3p, are inversely expressed and play exactly opposite roles in gastric cancer progression. Higher-5p with lower-3p expression pattern is significantly correlated with higher TNM stages and poor prognosis of gastric cancer patients. The increase of miR-574-5p/-3p ratio, named miR-574 arm-imbalance is partially due to the dynamic expression of their highly complementary targets in gastric carcinogenesis, moreover, the arm-imbalance of miR-574 is in turn involved and further promotes gastric cancer progression. Our results indicate that miR-574 arm-imbalance contribute to gastric cancer progression and re-modification of the miR-574-targets homeostasis may represent a promising strategy for gastric cancer therapy. Functional miRNAs derived from the 5p or 3p arm of some miRNA duplexes have opposite roles in cancer progression. Here, the authors show that oncogenic miR-574-5p has greater preference in aggressive gastric cancer as compared with miR-574-3p and this arm preference is partly dependent on complementary targets mediated miRNA decay. [ABSTRACT FROM AUTHOR]

Reduced graphene oxide (rGO)/Bi2Te3 nanocomposite powders with different contents of rGO have been synthesized by a one-step in-situ reductive method. Then, rGO/Bi2Te3 nanocomposite bulk materials were fabricated by a hot-pressing process. The effect of rGO contents on the composition, microstructure, TE properties, and carrier transportation of the nanocomposite bulk materials has been investigated. All the composite bulk materials show negative Seebeck coefficient, indicating n-type conduction. The electrical conductivity for all the rGO/Bi2Te3 nanocomposite bulk materials decreased with increasing measurement temperature from 25 °C to 300 °C, while the absolute value of Seebeck coefficient first increased and then decreased. As a result, the power factor of the bulk materials first increased and then decreased, and a power factor of 1340 μWm−1K−2 was achieved for the nanocomposite bulk materials with 0.25 wt% rGO at 150 °C. [ABSTRACT FROM AUTHOR]

As a promising eco‐friendly high‐performance thermoelectric material, SnSe single crystal has attracted much attention during the past several years. In this work, SnSe single crystal is prepared through a novel vapor deposition method in which polycrystalline SnSe is volatilized on a hot side (800–850 °C) and single‐crystalline SnSe spontaneously nucleates on the cold side (500–650 °C) based on the inside wall of a quartz ampoule. This crystal growth technique is beneficial for obtaining high‐purity SnSe crystal as some metal ions, such as Li+, Na+, and K+, in the quartz ampoule will be restricted from diffusing into the material. SnSe single crystal along the a‐axis is measured to experience a Pnma–Cmcm phase transition around 800 K where power factor (PF) exhibits the highest value of 6.2 µW cm−1 K−2 and total thermal conductivity ktot shows the lowest value of 0.48 W m−1 K−1. Accordingly, SnSe single crystal reaches a maximum ZT = 0.98 near phase transition temperature. These results not only provide an effective approach for pure SnSe single crystal fabrication, but also reveal the intrinsic electronic and phononic transport properties of thermoelectric SnSe. [ABSTRACT FROM AUTHOR]

All-inorganic cesium lead halide perovskites have been emerging as the promising semiconductor materials for next-generation optoelectronics. However, the fundamental question of how the environmental atmosphere affects their photophysical properties, which is closely related to the practical applications, remains elusive. Here, we report the dynamic switching between radiative exciton recombination and non-radiative carrier trapping in CsPbBr3 by controlling the atmospheric conditions. Specifically, we show that the photoluminescence (PL) intensity from the CsPbBr3 crystals can be boosted by ~ 60 times by changing the surrounding from vacuum to air. Based on the comprehensive optical characterization, near-ambient pressure X-ray photoelectron spectroscopy (NAP-XPS) as well as density functional theory (DFT) calculations, we unravel that the physisorption of oxygen molecules, which repairs the trap states by passivating the PL-quenching bromine vacancies, is accountable for the enhanced PL in air. These results are helpful for better understanding the optical properties of all-inorganic perovskites. Perovskite-based optoelectronics are expected to become an important component of devices such as solar cells and light-emitting diodes. However, how they are affected by environmental conditions is still not fully understood. The authors investigate the mechanisms, which occur for inorganic perovskites when in contact with ambient atmosphere and how this could potentially impact upon device performance. [ABSTRACT FROM AUTHOR]

Aqueous zinc‐ion batteries (AZIBs) with the merits of superior security, natural abundance, and inexpensive Zn hold great promises for next‐generation energy storage. Nevertheless, the instabilities of the Zn anodes arising from the unsatisfactory dendrite growth and parasitic reactions have seriously restricted their practical application. Herein, an interfacial protection engineering approach is proposed for stabilizing Zn anode via in‐situ constructing 3D hybrid fiber networks within high elastic polyether‐type polyurethane (TPEU) and super‐ionic conductor NaTi2(PO4)3 (NTP). This 3D NTP@TPEU fiber framework demonstrates synergistic effects of enhancing Zn2+ immigration kinetics and improving the desolvation process. Subsequently, such a superior protected interface induces a highly reversible Zn (002) deposition/stripping with a dendrites‐free feature. Moreover, the NTP@TPEU/Zn displays an ultralong lifespan of over 2000 cycles with an average Coulombic efficiency (CE) of 99.5% in the half‐cell configuration. To highlight, a full battery matched with Ca‐doped VO2 on carbon cloth cathode acquires an enhanced CE as high as 99.8% and delivers good cycling stability with a capacity retention of 81.6% at 2 A g−1 over 3000 cycles. These excellent outcomes provide a distinctive perspective of designing a highly stable zinc anode for the practical application of AZIBs. [ABSTRACT FROM AUTHOR]

On-chip ultra-wideband optical waveguide amplifiers are crucial for short-distance optical interconnections that utilize wavelength division multiplexing (WDM) technology. Silicon optical amplifiers still face significant challenges due to the indirect-band-gap nature and low rare earth solubility of silicon. This paper prepared a series of Er3+-Tm3+ co-doped La 2 O 3 –Al 2 O 3 glasses that are expected to be used in on-chip ultra-broadband optical waveguide amplifiers by aerodynamic levitation (ADL) technique, and further studied their luminescence characteristics and energy transfer process. Research results indicate that the glass composition 5Er 2 O 3 -0.6Tm 2 O 3 -43.4La 2 O 3 –51Al 2 O 3 is an optimal optical waveguide amplifier host material due to its excellent luminescence properties and ultra-broadband flat photoluminescence spectrum extending up to 440 nm. Moreover, positive gain can be obtained with a population ratio greater than 0.2, which further illustrates its feasibility as a matrix material for ultra-broadband optical waveguide amplifiers. The advancement of this material is expected to significantly aid in the fabrication and progress of next-generation ultra-wideband optical waveguide amplifiers. [ABSTRACT FROM AUTHOR]

Paecilomyces hepiali, belonging to the Eurotiales order Ascomycota, is an endoparasitic fungus that commonly exists in the naturalCordyceps sinensisanamorph stage. Here, we report the complete mitochondrial DNA sequences ofP. hepialifor the first time. The genome is 24,245 bp in length, encoding 15 protein-coding genes (PCGs), 2 rRNA genes, 25 tRNA genes and 3 homing endonucleases. The overall AT composition is 73.37% and the average AT content of PCG, rRNA, tRNA and non-coding region are 74.21%, 66.07%, 62.83% and 75.96%, respectively. Phylogenetic analysis with eight Ascomycota species and thirteen Basidiomycota species revealed thatP. hepialiis was more closely related toCordyceps bassiana, Cordycep smilitarisandCordyceps brongniartii. It is confirmed thatP. hepialiis a derivative ofCordyceps sinensis. This study provided valuable information on the gene contents of the mitochondrial genome and would facilitate the study of function and evolution ofP. hepiali. [ABSTRACT FROM AUTHOR]

Background. Endometrial lesions in patients with polycystic ovary syndrome (PCOS) exhibit complex pathological features, and these patients are at risk of both short-term and long-term complications. Complementary and alternative medicine (CAM), which is gradually becoming more accepted and is believed to be clinically effective, claims to be promising for treating PCOS, and thus its effect on the abnormal endometrium of PCOS patients should be assessed. The present meta-analysis sought to evaluate the efficacy and safety of CAM in treating endometrial lesions in patients with PCOS. Methods. Randomized trials on CAM were identified in four Chinese and seven English-language databases from their establishment to January 2020. The present study included patients diagnosed with PCOS and abnormal endometrial conditions who underwent CAM therapy independently or in combination with traditional western medicine. Data were extracted, and the Cochrane "risk of bias" tool was used to assess methodological quality. Effects were expressed as the relative risk (RR) or mean difference (MD/SMD) with 95% confidence interval (CI) as calculated with Rev Man 5.3. Results. A total of 13 randomized controlled trials were included, involving 1,297 PCOS patients treated for endometrial abnormalities. Methodological quality was generally unclear or had a low risk of bias. The trials tested four different types of CAM therapies (i.e., traditional Chinese medicine treatment, acupuncture treatment, traditional Chinese medicine in combination with western medicine treatment, and acupuncture in combination with western medicine treatment). CAM treatment could significantly reduce the endometrial thickness in PCOS patients compared to western medicine alone (SMD −0.88, 95% CI [−0.12, −0.57]; I2 = 64%). Compared with clomiphene treatment for the induction of ovulation, CAM treatment showed a clear improvement in endometrial thickness during ovulation (SMD 2.03, 95% CI [1.64, 2.02]; I2 = 48%). Moreover, CAM was more effective than western medicine alone in reducing the endometrial spiral artery pulsatility index. No significant difference was seen between CAM and traditional treatment when these were used to improve traditional Chinese medicine syndrome scores. Acupuncture alone or traditional Chinese medicines (taken orally) in combination with western medicine significantly increased the pregnancy rate of PCOS patients (RR 1.59, 95% CI [1.30, 1.93]; I2 = 51%, P < 0.00001), and CAM was more effective than western medicine alone for improving hormone levels. No serious adverse events were reported in 11 of the 13 trials. Conclusions. CAM may effectively ameliorate the endometrial condition of PCOS patients, and it can regulate the level of hormone secretion to increase the ovulation rate and the pregnancy rate. [ABSTRACT FROM AUTHOR]

Ytterbium doped Lu1.5Y1.5Al5O12 (LuYAG) nanocrystalline powders were synthesized by a wet chemical mixed precipitant co-precipitation (MPP) method, and then the mixed crystal of Yb:LuYAG was grown in an optical floating zone (OFZ) furnace at the speed of 6–10 mm/h, using a [111] oriented YAG seed crystal. The transmittance of the polished LuYAG crystal is close to the ideal value of LuAG or YAG. The X-ray rocking curve shows complete symmetry and the full width at half maximum (FWHM) is 10 arc-second, indicating the good quality of as grown Yb:LuYAG multicomponent garnet crystal. The thermal luminescent spectrum at room temperature shows four deep energy traps at around 1–1.3 eV. X-ray excited luminesce (XEL) spectra is measured to characterize the existence of LuAl or YAl shadow defects in the bulk single crystal. The emission peak at around 320 nm indicates that the LuYAG crystal prepared by OFZ have lower concentrations of antisite defects (AD) with respect to its Czochralski counterpart. [ABSTRACT FROM AUTHOR]

Graphite/poly(3,4-ethyenedioxythiophene) (PEDOT) nanocomposites were prepared by an in-situ oxidative polymerization process. The electrical conductivity and Seebeck coefficient of the graphite/PEDOT nanocomposites with different content of graphite were measured in the temperature range from 300 K to 380 K. The results show that as the content of graphite increased from 0 to 37.2 wt %, the electrical conductivity of the nanocomposites increased sharply from 3.6 S/cm to 80.1 S/cm, while the Seebeck coefficient kept almost the same value (in the range between 12.0 μV/K to 15.1 μV/K) at 300 K, which lead to an increased power factor. The Seebeck coefficient of the nanocomposites increased from 300 K to 380 K, while the electrical conductivity did not substantially depend on the measurement temperature. As a result, a power factor of 3.2 μWm−1 K−2 at 380 K was obtained for the nanocomposites with 37.2 wt % graphite. [ABSTRACT FROM AUTHOR]

Polypyrrole (PPy) with different morphologies (e.g., particles, nanotubes, and nanowires) were successfully prepared by adding or without adding different kinds of surfactants through a chemical oxidative polymerization method, respectively. The results show that the morphologies of PPy can be effectively controlled and have a significantly effects on their thermoelectric properties. The PPy nanowires exhibit the highest electrical conductivity and Seebeck coefficient among the various PPy morphologies, such as particles, nanotubes, and nanowires, so PPy nanowires were chosen to prepare PPy nanowire/graphene thermoelectric composites via a soft template polymerization method using cetyltrimethyl ammonium bromide as the template. Both electrical conductivity and Seebeck coefficient of the PPy nanowire/graphene composites increased as the content of graphene increases from 0 to 20 wt %, and as the measured temperature increases from 300 K to 380 K, which leds to the same trend for the power factor. A highest power factor of 1.01 μWm−1K−2 at ~380 K was obtained for the PPy nanowire/graphene composites with 20 wt % PPy nanowire, which is about 3.3 times higher than that of the pure PPy nanowire. [ABSTRACT FROM AUTHOR]

PMN-PT films were deposited on GaN/sapphire substrates via pulsed laser deposition without any intermediate buffer layers, and epitaxial perovskite (111) 0.65PMN-0.35PT films on wurtzite GaN(0002) surfaces were obtained by adjusting the experimental parameters including substrates temperature and O2 pressure. The microstructures and electrical properties of PMN-PT/GaN heterostructure were characterized by reflection high-energy electron diffraction, X-ray diffraction, atom force microscope, transmission electron microscope and polarization-electric field (P-E) measurements. The as-grown PMN-PT films exhibit highly (111) oriented perovskite crystal structure. The in-plane orientation relationship of PMN-PT film with respect to GaN is (111)×[11-2] PMN-PT//(0002)×[11-20] GaN. A domain matching epitaxy model is proposed to account for the epitaxial growth mechanism of PMN-PT on GaN. The P-E curves show typical ferroelectric characteristics, while the remnant polarization and coercive field are about 18.1 μC/cm2 and 75 kV/cm, respectively. This work provides a good start point for the further development of advanced electronic devices based on the integration of ferroelectric PMN-PT with wide-gap GaN semiconductor. [ABSTRACT FROM AUTHOR]

(Tb 0.5 Y 0.5) 2 O 3 transparent ceramics have been prepared by wet chemical co-precipitation route and flowing H 2 atmosphere sintering. The optical quality, microstructure and magneto-optical properties of the ceramics were investigated. No sintering aids or milling were adopted in the ceramic fabrication processing. The cold isostatic pressed green compact could be sintered to be transparent (Tb 0.5 Y 0.5) 2 O 3 ceramic at 1800 ℃ in flowing H 2 atmosphere. The mechanical polished ceramic showed the good transmittance from visible to near infrared wavelength, corresponding to a 71.9% transmittance at 1400 nm wavelength. The Verdet constant measured at 632.8 nm of the (Tb 0.5 Y 0.5) 2 O 3 transparent ceramics was -220.19 rad T−1 m-1, which was 1.64 times that of Tb 3 Ga 5 O 12 single crystal. [ABSTRACT FROM AUTHOR]

R 3 Fe 5 O 12 (RIG) crystals are the key elements for magneto-optical isolators in the near-infrared (NIR) to mid-infrared (MIR) region, with ever-growing demands for integrated photonics. However, the growth of high-quality single crystals is still a big obstacle. The effect of rare earths on the optical and magneto-optical properties of YIG crystals is not well understood. Herein, a series of high quality Tb3+ doped yttrium iron garnet (Y 3-x Tb x Fe 5 O 12 , x = 0, 0.5, 1.0, 1.5, 3.0) crystals have been successfully obtained by the flux-Bridgman method, with sizes over 20 mm. Tb:YIG crystals reserve typical cubic garnet structure, with spatial group of Ia3d. The lattice constants increase from 12.377 Å (YIG) to 12.448 Å (TbIG). The refractive index decreases from 2.38 (500 nm) to 2.11 (2500 nm) for YIG crystal, and it reduces from 2.51 (500 nm) to 2.17 (2500 nm) for TbIG crystal. The optical dispersion of the refractive indices was well fitted by the Wemple and DiDomenico (WDD) and the Sellmeier models, respectively. Relatively lower values of the absorption coefficient of the Tb:YIG crystals confirm the high transparency in the NIR region. The characteristic absorption of Tb3+ was observed from 1700 nm to 2500 nm. The specific Faraday rotation angles (θ F) of both YIG and TbIG decrease with increasing wavelength, reaching 235.4 and 366.5 °/cm at 1300 nm, respectively. Compared with that of YIG, θ F of TbIG crystal shows stronger wavelength dependence. This work provides more insight into the role of rare earths on the optical and magneto-optical behavior of RIG crystals, which will accelerate the design of high-performance magneto-optical crystals for application in NIR-MIR wavelength. [ABSTRACT FROM AUTHOR]

Europium-doped bismuth silicate (Bi4Si3O12) phosphor has been prepared by microwave irradiation method and its crystal structure is determined using Rietveld method. As-prepared phosphor consists of spherical, monodispersed particles with few agglomeration, high crystallinity, and narrow grain size distribution. The phosphor can be efficiently excited in the wavelength range of 260-400 nm, which matched well with the emission wavelengths of NUV LED chips. The photoluminescence spectra exhibit the highest emission peak at 703 nm originating from 5D0 → 7F4 transition of Eu3+ under NUV excitation. The luminescence lifetime for Bi4Si3O12: 2 at% Eu3+ phosphor decreases from 2.11 to 1.86 ms with increasing temperature from 10 to 498 K. This behavior of decays is discussed in terms of radiative and nonradiative decays dependence on temperature. The thermal quenching mechanism of 5D0 emission of Eu3+ in Bi4Si3O12 phosphor is a crossover process from the 5D0 level of Eu3+ to a ligand-to-europium (O2− → Eu3+) charge transfer state. The quantum efficiency of the phosphor under 393 nm excitation is found to be 14.5%, which is higher than that of the commercial red phosphors Y2O3: Eu3+, Y2O2S: Eu3+. The temperature effect on CIE coordinate was discussed in order to further investigate the potential applications. [ABSTRACT FROM AUTHOR]

Albeit the majority of eukaryotic genomes can be pervasively transcribed to a diverse population of lncRNAs and various subtypes of lncRNA are discovered. However, the genome‐wide study of miRNA‐derived lncRNAs is still lacking. Here, it is reported that over 800 miRNA gene‐originated lncRNAs (molncRNAs) are generated from miRNA loci. One of them, molnc‐301b from miR‐301b and miR‐130b, functions as an "RNA decoy" to facilitate dissociation of the chromatin remodeling protein SMARCA5 from chromatin and thereby sequester transcription and mRNA translation. Specifically, molnc‐301b attenuates erythropoiesis by mitigating the transcription of erythropoietic and translation‐associated genes, such as GATA1 and FOS. In addition, a useful and powerful CRISPR screen platform to characterize the biological functions of molncRNAs at large‐scale and single‐cell levels is established and 29 functional molncRNAs in hematopoietic cells are identified. Collectively, the focus is on miRNA‐derived lncRNAs, deciphering their landscape during normal hematopoiesis, and comprehensively evaluating their potential roles. [ABSTRACT FROM AUTHOR]

Objectives: To systematically appraise the methodologies used for guidelines for positron emission tomography (PET) imaging and to compare the consistency of these recommendations. Methods: We searched PubMed, EMBASE, four guideline databases, and Google Scholar to identify evidence-based clinical practice guidelines pertaining to the use of PET, PET/computed tomography (CT), or PET/magnetic resonance in routine practice. We assessed the quality of each guideline using the Appraisal of Guidelines for Research and Evaluation II instrument and compared recommendations regarding indications for 18F-fluorodeoxyglucose (FDG) PET/CT. Results: Thirty-five guidelines for PET imaging, published between 2008 and 2021, were included. These guidelines performed well in the domains of scope and purpose (median 80.6%, inter-quartile range [IQR] 77.8–83.3%) and clarity of presentation (median 75%, IQR 69.4–83.3%), but poorly in applicability (median 27.1%, IQR 22.9–37.5%). Recommendations for 48 indications in 13 cancers were compared. Considerable inconsistencies in the direction of whether to support the use of FDG PET/CT were observed in 10 (20.1%) indications pertaining to 8 cancer types: head and neck cancer (treatment response assessment), colorectal cancer (staging in patients with stages I–III disease), esophageal cancer (staging), breast cancer (restaging and treatment response assessment), cervical cancer (staging in patients with stage < IB2 disease and treatment response assessment), ovarian cancer (restaging), pancreatic cancer (diagnosis), and sarcoma (treatment response assessment). Conclusions: Current guidelines for PET imaging vary in methodological quality and provided considerably inconsistent recommendations. Efforts are needed to improve adherence to guideline development methodologies, to synthesis high-quality evidence, and to adopt standard terminologies. Protocol registration number: PROSPERO CRD42020184965. Clinical relevance statement: Guidelines for PET imaging provide considerably inconsistent recommendations and vary in methodological quality. It is suggested that clinicians be critical of these recommendations when applying them in practice, that guideline developers adopt more rigorous development methodologies, and that researchers prioritize research gaps identified by current guidelines. Key Points: • PET guidelines vary in methodological quality and provided inconsistent recommendations. Efforts are needed to improve methodologies, synthesize high-quality evidence, and standardize terminologies. • Among six domains of methodological quality assessed by the AGREE II tool, guidelines for PET imaging performed well in scope and purpose (median 80.6%, inter-quartile range 77.8–83.3%) and clarity of presentation (75%, 69.4–83.3%), but poorly in applicability (27.1%, 22.9–37.5%). • Among the 48 recommendations (for 13 cancer types) compared, conflicts in the direction of whether to support FDG PET/CT use were observed in 10 (20.1%), for 8 cancer types (i.e., head and neck, colorectal, esophageal, breast, cervical, ovarian, pancreatic, and sarcoma). [ABSTRACT FROM AUTHOR]

Erbium-doped crystals are well-suited for eye-safe solid-state laser systems around 1.5 μm. Broadband and high-gain Er-doped laser crystals can achieve high-power tunable laser output, which plays a great role in promoting commercial eye-safe laser research. Herein, the 2 at% Er-doped bismuth germanium silicate (BGSO) laser crystal is successfully grown by the vertical Bridgman method. The X-ray Rietveld refinement was used to obtain the structural parameters. The spectroscopic parameters of Er ions in BGSO crystal are calculated and analyzed with Judd-Ofelt theory. Furthermore, the broadband luminescence is observed in the wavelength range of 1450–1600 nm. The stimulated emission cross-section is calculated around 1500 nm, which largest value is 5.31 × 10−20 cm2 at 1543 nm. Meanwhile, the luminous efficiency of BGSO crystal in the eye-safe band is further characterized and explored by studying the energy transfer process and anomalous thermal quenching in the 550 nm and 660 nm bands. All results indicate that the Er: BGSO crystal is a promising broadband eye-safe laser material. [ABSTRACT FROM AUTHOR]

Background: Routinely collected health data (RCD) are important resource for exploring drug treatment effects. Adequate reporting of data source profiles may increase the credibility of evidence generated from these data. This study conducted a systematic literature review to evaluate the reporting characteristics of databases used by RCD studies to explore the effects of drug treatment. Methods: Observational studies published in 2018 that used RCD to explore the effects of drug treatment were identified by searching PubMed. We categorized eligible reports into two groups by journal impact factor (IF), including the top 5 general medical journals (NEJM, Lancet, JAMA, BMJ and JAMA Internal Medicine) and the other journals. The reporting characteristics of the databases used were described and compared between the two groups and between studies citing and not citing database references. Results: A total of 222 studies were included, of which 53 (23.9%) reported that they applied data linkage, 202 (91.0%) reported the type of database, and 211 (95.0%) reported the coverage of the data source. Only 81 (36.5%) studies reported the timeframe of the database. Studies in high-impact journals were more likely to report that they applied data linkage (65.1% vs. 20.2%) and used electronic medical records (EMR) (73.7% vs. 30.0%) and national data sources (77.8% vs. 51.3%) than those published in other medical journals. There were 137/222 (61.7%) cited database references. Studies with database-specific citations had better reporting of the data sources and were more likely to publish in high-impact journals than those without (mean IF, 6.08 vs. 4.09). Conclusions: Some deficits were found in the reporting quality of databases in studies that used RCD to explore the effects of drug treatment. Studies citing database-specific references may provide detailed information regarding data source characteristics. The adoption of reporting guidelines and education on their use is urgently needed to promote transparency by research groups. [ABSTRACT FROM AUTHOR]

Nanocrystalline powders and pressureless sintering (NC-PLSH) were used in a H 2 atmosphere to fabricate 4 at.% La3+ doped (Tb x Lu 0.96−x) 2 O 3 magneto-optical transparent ceramics. La3+ was utilised as a sintering aid, and Lu3+ was used as a phase stabiliser. A component of the (Tb x Lu 0.96−x La 0.04) 2 O 3 magneto-optical material was designed and investigated based on powder sinterability and green compact sintering. Transparent (Tb x Lu 0.96−x La 0.04) 2 O 3 ceramics were obtained by using a one-step sintering process in H 2 atmosphere, without the need for subsequent hot isostatic pressing. The in-line transmittance of the as-polished 4 at.% La3+:(Tb 0.8 Lu 0.16) 2 O 3 ceramic was 79% at 1400 nm. The measured Verdet constant at wavelengths of 633 nm and 1064 nm was 354 rad/(T·m) and 100.2 rad/(T·m), respectively. The required length of the (Tb 0.8 Lu 0.16 La 0.04) 2 O 3 ceramics was 63% less than that of Tb 3 Ga 5 O 12 ceramics. [ABSTRACT FROM AUTHOR]

Abstract: Langasite (La3Ga5SiO14,LGS) and its isomorphs, have attracted much attention for their potential for surface acoustic wave (SAW) and bulk acoustic wave (BAW) applications. Among these homologous compounds, Sr3Ga2Ge4O14 (SGG) attracted our attention due to its superior piezoelectric properties and lower growth temperature. In this work, SGG single crystal has been grown successfully by the vertical Bridgman method with crucible-sealing technique. SGG wafers of 2in. have been fabricated. The basic physical properties of SGG crystals were measured. The results demonstrate that piezoelectric and mechanical properties of SGG crystals are better than that of LGS crystal and it is expected to be a potential substrate material for SAW and BAW applications. [Copyright &y& Elsevier]

Abstract: Φ2′′ Sr3Ga2Ge4O14 (SGG) single crystals have been grown by the modified Bridgman method. The growth defects were investigated and the growth conditions were optimized. Using Φ1′′ SGG crystal as seed, crack-free and inclusion-free SGG single crystal up to 54mm in diameter and 50–90mm in length were reproducibly grown along the 〈001〉 direction. The piezoelectric constants and electromechanical coupling coefficients were measured and the results showed that SGG crystal is a potential substrate material for piezoelectric applications. [Copyright &y& Elsevier]

A series of uranium-doped lithium niobate crystals (LN:U) were successfully grown by the modified vertical Bridgman method, and their photorefractive properties in the visible band were systematically investigated for the first time. The occupancy of uranium ions and photorefractive centers is discussed. LN:U realizes multi-wavelength holography. [ABSTRACT FROM AUTHOR]

(Tb 0.8 Y 0.2-x La x) 2 O 3 transparent ceramics were prepared by using co-precipitation method combined with pressure-less sintering in flowing H 2 atmosphere. Microstructure, optical transmittance, elements composition, and Verdet constant of the (Tb 0.8 Y 0.2-x La x) 2 O 3 ceramics were studied. The amount of La 2 O 3 is crucial for the formation of expected transparent (Tb 0.8 Y 0.2) 2 O 3. With increasing content of La 2 O 3 , the number of pores and the grain size of as-fabricated (Tb 0.8 Y 0.2-x La x) 2 O 3 ceramics both decrease. When 4 at.% La 2 O 3 is doped, the (Tb 0.8 Y 0.16) 2 O 3 transparent ceramics shows the highest transmittance of 73.3% at 1400 nm wavelength. With holding time increasing from 8 h to 15 h, the average grain size of (Tb 0.8 Y 0.16 La 0.04) 2 O 3 ceramics gradually increases from 5 μm to 13 μm. The Verdet constant measured at 633 nm is −352 rad/T·m, which is 2.63 times higher than that of TGG. In addition, large-size ceramics with Φ 20 mm × 3 mm and Φ 30 mm × 3 mm were also successfully obtained. [ABSTRACT FROM AUTHOR]

Mixed human umbilical cord‐derived mesenchymal stem cells (UC‐MSCs) are widely applied in clinical trials to treat various diseases due to their multipotent differentiation potential and immune regulatory activities. However, the lack of a clear understanding of their heterogeneity hampers their application to precisely treat diseases. Moreover, few studies have experimentally authenticated the functions of so‐called UC‐MSC subpopulations classified from scRNA‐seq samples. Here, this work draws a large‐scale single‐cell transcriptomic atlas and identified three clusters (C1, C2, and C3), representing the primed, intermediate, and stem statuses individually. The C1 and C3 clusters feature higher expression of cytokines and stemness markers, respectively. Surprisingly, further experimental assays reveal that the BAMBIhighMFGE8high C1 subgroup has a unique phenotype, distinct transcriptomic profile, and limited adipogenic differentiation potential but compromised immunosuppressive activity in vitro and in vivo in lupus mice. Thus, this work is helpful to clarify the nature of human UC‐MSCs and to choose optimal MSC types to treat specific diseases in the future. [ABSTRACT FROM AUTHOR]

Due to its environmental cleanliness and high energy density, hydrogen has been deemed as a promising alternative to traditional fossil fuels. Photocatalytic water-splitting using semiconductor materials is a good prospect for hydrogen production in terms of renewable solar energy utilization. In recent years, halide perovskite nanocrystals (NCs) are emerging as a new class of fascinating nanomaterial for light harvesting and photocatalytic applications. This is due to their appealing optoelectronic properties, such as optimal band gaps, high absorption coefficient, high carrier mobility, long carrier diffusion length, etc. In this review, recent progress in halide perovskite NCs for photocatalytic hydrogen evolution is summarized. Emphasis is given to the current strategies that enhance the photocatalytic hydrogen production performance of halide perovskite NCs. Some scientific challenges and perspectives for halide perovskite photocatalysts are also proposed and discussed. It is anticipated that this review will provide valuable references for the future development of halide perovskite-based photocatalysts used in highly efficient hydrogen evolution. [ABSTRACT FROM AUTHOR]

Ultrathin porous Co3O4 nanosheets are synthesized successfully, the thickness of which is about three unit-cell dimensions. The enhanced oxygen evolution reaction (OER) performance and electronic interaction between Co3O4 and Au is firstly reported in Co3O4 ultrathin porous nanosheets by physically mixing with Au nanoparticles. With the loading of the Au nanoparticles, the current density of ultrathin porous Co3O4 nanosheets is enhanced from 9.97 to 14.76 mA cm−2 at an overpotential of 0.5 V, and the overpotential required for 10 mA cm−2 decreases from 0.51 to 0.46 V, smaller than that of commercial IrO2 (0.54 V). Furthermore, a smaller Tafel slope and excellent durability are also obtained. Raman spectra, XPS measurement, and X-ray absorption near edge structure spectra (XANES) show that the enhanced OER ascribed to a higher Co2+/Co3+ ratio and quicker charge transfer due to the electronic interaction between Au and ultrathin Co3O4 nanosheets with low-coordinated surface, and Co2+ ions are beneficial for the formation of CoOOH active sites. [ABSTRACT FROM AUTHOR]

Ovarian cancer is a fatal gynecological cancer due to the lack of effective screening strategies at early stage. This study explored the utility of DNA methylation profiling of blood samples for the detection of ovarian cancer. Targeted bisulfite sequencing was performed on tissue (n = 152) and blood samples (n = 373) obtained from healthy women, women with benign ovarian tumors, or malignant epithelial ovarian tumors. Based on the tissue-derived differentially-methylated regions, a supervised machine learning algorithm was implemented and cross-validated using the blood-derived DNA methylation profiles of the training cohort (n = 178) to predict and classify each blood sample as malignant or non-malignant. The model was further evaluated using an independent test cohort (n = 184). Comparison of the DNA methylation profiles of normal/benign and malignant tumor samples identified 1272 differentially-methylated regions, with 49.4% hypermethylated regions and 50.6% hypomethylated regions. Five-fold cross-validation of the model using the training dataset yielded an area under the curve of 0.94. Using the test dataset, the model accurately predicted non-malignancy in 96.2% of healthy women (n = 53) and 93.5% of women with benign tumors (n = 46). For patients with malignant tumors, the model accurately predicted malignancy in 44.4% of stage I-II (n = 9), 86.4% of stage III (n = 59), 100.0% of stage IV tumors (n = 6), and 81.8% of tumors with unknown stage (n = 11). Overall, the model yielded a predictive accuracy of 89.5%. Our study demonstrates the potential clinical application of blood-based DNA methylation profiling for the detection of ovarian cancer. • Blood-based DNA methylation profiling is feasible in identifying patients with malignant or non-malignant ovarian tumor • Malignant ovarian tumor samples had distinct DNA methylation profile than normal/benign ovarian tissues • Machine learning classifier had a positive predictive value of 93.7% and negative predictive value of 86.8% [ABSTRACT FROM AUTHOR]

The scandium (Sc) and aluminum (Al) co-doped antimony-selenium (Sb45Se25Sc7Al23) thin film was fabricated and systematically investigated in this study. The results reveal that our examined Sb45Se25Sc7Al23 thin film has good thermal stability (the failure temperature for ten years data retention ∼103 °C) and the fast phase change speed (5 ns) at same time. Besides, the Sb45Se25Sc7Al23 thin film shows no multiple phase change, which derives from the fact that no formation of new Sc or Al related phases that are able to trigger multiple states in the thin film. However, it is found that more Sb precipitation is formed by the increase of dopants, which may increase the tendency of multiple phase change. All results suggest Sb45Se25Sc7Al23 thin film would be a good candidate used for phase change random access memory applications. [ABSTRACT FROM AUTHOR]

The Er:BGSO polycrystals with different Er3+ ions doping concentrations were successfully prepared by solid-state synthesis method. The phase and structure parameters of these crystals were investigated systematically. The calculation of DFT proves that Bi4(Ge0.5Si0.5)3O12 is the indirect-bandgap material with a bandgap of 3.86 eV. Bi4(Ge0.5Si0.5)3O12 doped with 2 at.% Er3+ ions can suppress the effect of up-conversion luminescence (UCL) effectively, and its stimulated emission cross-section and fluorescence lifetime at 1.5 μm are 2.25 × 10−20 cm2 and 5.19 ms, respectively. In addition, the luminescence of the crystal in the C-band is not sensitive to temperature. The high luminescence intensity, wide emission band, and proper thermal stability indicate that 2 at.%Er:Bi4(Ge0.5Si0.5)3O12 is a potential ideal gain medium of C-band laser. [ABSTRACT FROM AUTHOR]

Lu 3 Al 5 O 12 (LuAG) nanocrystalline powders were synthesized by using ammonium hydroxide (NH 4 OH, AH) and ammonium hydrogen carbonate (NH 4 HCO 3 , AHC) as mixed precipitant. In the absence of sintering aids such as TEOS, MgO or ZrO 2 , the obtained LuAG powders showed good sinterability in H 2 atmosphere (PLSH) at low temperature. The in-line transmittance of LuAG ceramic reached 81% in the whole visible light band from 400 nm to 800 nm. The average grain size of obtained transparent ceramics was ranged in 1–6 μm at different sintering temperatures by PLSH. Various kinds of rare earth ions, such as Nd, Yb, Ce, Pr, and Tm doped RE:LuAG transparent ceramics could be prepared by PLSH technology without sintering aids and HIP post-treatment. Through PLSH technology, RE:LuAG transparent ceramics show high optical quality and large aperture size. [ABSTRACT FROM AUTHOR]

A new silicate garnet phosphor, Lu 2− x CaMg 2 Si 2.9 Ti 0.1 O 12 : x Ce was synthesized by a high temperature solid-state reaction under reductive atmosphere. X-ray diffraction (XRD) showed that the powder was pure garnet phase. The emission and excitation spectrum indicated that the Lu 2− x CaMg 2 Si 2.9 Ti 0.1 O 12 : x Ce phosphors could absorb blue light in the spectral range of 400–550 nm efficiently and exhibit bright yellow–orange emission in the range of 520–750 nm. With the increase of Ce 3+ concentration, the emission band of Ce 3+ showed a red shift. Interestingly, the concentration quenching occurred when the Ce 3+ concentration exceeded 4 mol%. The temperature-dependent luminescent properties of the phosphors were discussed and the Lu 1.96 CaMg 2 Si 2.9 Ti 0.1 O 12 :0.04Ce phosphors showed good performances in color temperature (2430 K) and potential applications for warm white LEDs. [ABSTRACT FROM AUTHOR]

GaAs crystals are important III–V compound semiconductor materials and the bandgap and quantum efficiency can be optimized by doping. However, the doping may bring some problems to the crystal growth. In this paper, Si‐doped GaAs crystals are grown by the modified vertical Bridgman method and the influence of Si doping on dislocations and mechanical properties are discussed. It is found that a proper amount of Si doping significantly reduces the dislocation density of GaAs crystals. The mechanical properties of (100), (110), (111), and (511) planes are measured, and the results show that the mechanical properties of Si‐doped GaAs crystals have obvious anisotropy. The (111) plane has the strongest mechanical properties among them. The Vickers hardness, fracture toughness, nanoindentation hardness, and elastic modulus of the (111) plane are 6.05 GPa, 0.69 MPa m1/2, 10.82 GPa, 138.7 GPa, respectively. Moreover, Si doping can improve the mechanical properties of GaAs crystals. [ABSTRACT FROM AUTHOR]

• Recent advances for the growth of rare earth orthoferrites RFeO 3 single crystals are summarized. • The strategies for the modulation of magnetic and magneto-optical properties are analyzed. • Ongoing prospects for RFeO 3 single crystals are proposed. Currently, rare earth orthoferrites RFeO 3 crystals are gaining tremendous interests, thanks to their exotic magnetic, multiferroic and magneto-optical characteristics. This family displays distinctive advantages of ultrafast response in nanoseconds and much enhanced sensitivity for magneto-optical (MO) switches and isolators. Moreover, enriched magnetic transitions and ultrafast opto-magnetic modulation have been rationally achieved, favoring ultrafast magnetic recording with much lower energy consumption. This work comprehensively summarizes the recent advances of magneto-optical RFeO 3 single crystals, including the crystal growth, the regulation of magnetic properties and the tailoring of opto-magnetic interactions. The related mechanism for the modulation of magneto-optical interactions is also analyzed in details, facilitating deeper insight into the design and further exploration of RFeO 3 crystals for the potential applications in the fields of novel spintronic and ultrafast magneto-optical devices. [ABSTRACT FROM AUTHOR]

Abstract: Fine-grained Nd3+:Lu2O3 transparent ceramic was developed by a two-step sintering method in flowing H2 atmosphere at T 1 =1720°C for 15min and T 2 =1620°C for 10h. The initial nanopowders were synthesized by a wet chemical processing with a uniform particle size of about 40nm. The average grain size of the obtained 3at.% Nd3+:Lu2O3 ceramic was 406nm, which is ∼150 times smaller than the coarse-grained ceramic by normal H2 sintering. The emission intensity of the fine-grained transparent ceramic is 3 times of its coarse-grained counterpart, indicating higher Nd concentration without serious quenching in fine-grained transparent ceramic is possible, which agreed well with the prediction of an atomistic modeling work with YAG. EXAFS research demonstrated that with decreasing grain size, higher degree of disorder factor of the local environment of doped Nd atoms was discovered. [Copyright &y& Elsevier]

Abstract: This study presents the luminescent properties of Yb3+/Tm3+ co-dopant ions inside a new host glass based on bismuth germanates. Judd–Ofelt intense parameters, radiative transition rate, radiative lifetime, and branching ratios of Tm3+ in the present glass are calculated based on the absorption spectrum. A strong 1.8μm emission was observed in the Yb3+/Tm3+ co-doped bismuth germanate glass upon the excitation of a conventional 980nm laser diode. Using a spectral overlap model, the micro parameter for direct energy transfer from Yb3+ ions to Tm3+ ions (C DA ) was found to be almost 30 times larger than the back energy transfer from Tm3+ ions to Yb3+ ions (C AD ). The linear dependence of energy transfer probability on the co-dopant concentration exhibits that the energy transfer is assisted by energy migration among donor ions. The large energy transfer efficiency (89%) indicates that the Yb3+/Tm3+ co-doped bismuth germanate glass is a good candidate for the 1.8μm laser. [Copyright &y& Elsevier]

Shell-free K 2 Ta 1-x In x F 7 : Mn4+ red phosphor was synthesized by introducing In3+ ions in K 2 TaF 7 : Mn4+ with a non-centrosymmetric octahedral structure. The strategy of the heterogeneous substitution of In3+ by Ta5+ further distorted the octahedral structure, effectively enhanced the emission intensity of Mn4+. Its overall luminous intensity was increased to 6.9 times that of K 2 TaF 7 : Mn4+. Moreover, the red phosphor with a homogeneous core-shell structure was successfully prepared by using a weak reducing agent citric acid to solve the problem of poor water resistance. After soaking in water for 10 days, the emission intensity of the red phosphor with a homogeneous core-shell structure retained 90% of the initial value. It is the first time to successfully construct a core-shell structure for A 2 BF 7 : Mn4+ type fluoride phosphors to effectively improve its water resistance. Mixing it with commercial YAG: Ce3+ yellow phosphor and encapsulating them with a commercial blue chip led to the development of warm white light-emitting diodes (WLEDs) with good qualities. K 2 Ta 1-x In x F 7 : Mn4+ red phosphor with homogeneous core shell is a novel red phosphor with good luminous performances and excellent water resistance. [Display omitted] • In3+ partially replaced Ta5+ in K 2 TaF 7 :1.0 mol%Mn4+, increasing its luminous intensity by 6.9 times. • Successfully constructed a homogeneous shell for K 2 Ta 1-x In x F 7 : Mn4+. • The homogeneous shell greatly improved the water resistance of the phosphor. • After 10 days of immersion, KTIF:1.0 mol%Mn4+@KTIF can still achieved warm WLED. [ABSTRACT FROM AUTHOR]