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The radiation detection performance of CZT epitaxial single crystal grown by the Close Space Sublimation (CSS) method is hindered by inherent defects. However, significant improvement in this work is achieved through annealing in a Te 2 atmosphere. The saturation channel value of the total energy peak of the detector for 241Am α-particles has shown a substantial increase from 1900 to 6000, resulting in a notable enhancement of the carrier collection efficiency. After annealing, the detector's energy resolution to 241Am gamma-rays can reach 8.3%, representing the highest energy resolution achieved by CSS growth of CZT materials. This remarkable achievement holds great promise for its potential application in the field of low-energy detection. Analysis of the laser-beam-induced current (LBIC) curve results reveals that the surface recombination of the detector is more pronounced prior to annealing, adversely affecting the transport process of photogenerated carriers. The low-temperature photoluminescence (PL) results and I–V curve demonstrate a significant compensation effect on the shallow acceptor level V Cd after annealing, leading to a reduced concentration of free carriers and subsequently leading to lower leakage current and improved signal-to-noise ratio for the detector. The concurrent reduction in leakage current and surface recombination contributes collectively to improving the radiation detection performance of the CZT detector. These findings underscore the importance of annealing in a Te 2 atmosphere as a viable method for mitigating defects and optimizing the performance of CZT epitaxial single crystals, showcasing the potential for broader applications in the field of low-energy detection. • The leakage current is reduced from 1.3 nA to 0.59 nA under the applied bias voltage of 0.5 V, which makes the detector obtain a good signal-to-noise ratio. • The surface recombination rate decreased from 13.78 × 106 cm s−1 to 3.82 × 105 cm s−1, significantly improving the carrier collection efficiency. • The energy resolution to 241Am@59.5 KeV gamma-rays of the detector reached 8.3% for the first time, which is expected to be applied in the field of low energy detection. [ABSTRACT FROM AUTHOR]

In the practical application of CdZnTe photon counting detectors, severe detector counting distortion can be caused by pulse pileup. A count rate correction method in this paper is proposed to solve this problem. In this method, the case where multi-photons are recorded by higher energy regions due to pulse pileup crossing the energy threshold is considered to calculate the true count rates under all energy bins. A verification method based on Poisson distribution is also proposed to evaluate the accuracy of the correction method. A 16-pixel linear array CdZnTe photon counting detector was used for verification. Taking the dual-energy bin as an example, this method was introduced, and the true count rates of the high- and low-energy bins are successfully calculated. The result was highly consistent with the verification result, which proves the reliability of the proposed method. [ABSTRACT FROM AUTHOR]

It is of significance that the wettability between the molten alloy and the Al 2 O 3 affects the inclusion removal, nozzle clogging and refractory erosion. In the present work, the wettability between the Al 2 O 3 substrate and Fe–P–Ti alloys with different Ti content was investigated by using the sessile droplets method. The interfacial characteristics were investigated by scanning electron microscope (SEM). The contact angles between the sintered Al 2 O 3 substrate and Fe–P–Ti alloys with 0, 0.05, 0.10 and 0.15 ​wt% Ti are 100.1°, 97.3°, 94.5° and 90.5°, respectively. The oxidation of [Al] and [Ti] in the molten alloys leads to the formation of the oxides on the droplets. With the increase of Ti content in the Fe–P–Ti alloys, the formed oxides change from Al 2 O 3 to Ti-containing oxides. The reaction between [Ti] and Al 2 O 3 substrate in the interface results in the formation of Ti-containing oxides. The quantity of the interfacial oxides increases with the increase of Ti content in the alloys. As a result, the synergetic effect of the formation of the interfacial products and the oxides on the surface of droplets leads to the decrease of the contact angles between the Al 2 O 3 substrate and Fe–P–Ti alloys due to the increase of Ti content. [ABSTRACT FROM AUTHOR]

Drug-based supramolecular self-assembling delivery systems have enhanced the bioavailability of chemotherapeutic drugs and reduced systemic side effects; however, improving the delivery efficiency and responsive release ability of these systems remains challenging. This study focuses primarily on the utilization of per-6-thio-β-cyclodextrin (CD) to link a significant quantity of paclitaxel (PTX) via ROS-sensitive thioketal (TK) linkages (designated as CDTP), thereby allowing efficiently drug release when exposed to high levels of reactive oxygen species (ROS) in the tumor microenvironment. To construct these supramolecular nanoparticles (NPs) with CDTP, we introduced PEGylated ferrocene (Fc) through host-guest interactions. The intracellular hydrogen peroxide (H 2 O 2) is converted into hydroxyl radicals (•OH) through the Fc-catalyzed Fenton reaction. Additionally, the generated Fc+ consumes the antioxidant glutathione (GSH). In both in vivo and in vitro experiments, CDTP@Fc-PEG NPs were absorbed effectively by tumor cells, which increased levels of ROS and decreased levels of GSH, disrupting the redox balance of cancer cells and increasing their sensitivity to chemotherapy. Furthermore, CDTP@Fc-PEG NPs exhibited high tumor accumulation and cytotoxicity without causing significant toxicity to healthy organs. Collectively, our results suggest CDTP@Fc-PEG NPs as a promising supramolecular nano-delivery platform for high drug-loading of PTX and synergistic chemotherapy. [Display omitted] • The ROS-driven supramolecular NPs has been constructed successfully and corresponding characterizations have been conducted. • Supramolecular prodrug nano-delivery system that can respond to the TME, while also demonstrating a high drug-loading capacity and delivery efficiency. • The results show that the nanoparticle can deplete GSH and amplify ROS simultaneously, resulting in the disruption of redox homeostasis. And the chemosensitization due to redox imbalance has also verified. • The results of in vitro and in vivo experiments both confirmed the excellent antitumor capability and favorable biosafety of the nanoparticle. [ABSTRACT FROM AUTHOR]

• Rainbow signal inversion algorithm based on ResNet and multi-objective regression. • The algorithm is comparable in accuracy to traditional ones but three times faster. • The structure and hyperparameters of the algorithm are determined in detail. • Loss competition relationship between droplet size and refractive index is studied. • An experimental validation system was built to verify the generalizability. Traditional standard rainbow inversion algorithms for retrieving droplet size and refractive index require time-consuming complex data pre-processing and multiple calculations, while optimized. This paper proposes a novel standard rainbow signal inversion algorithm based on residual networks and multi-objective regression. The algorithm requires only simple data pre-processing and is tested on a simulated data set covering representative signals from droplets with refractive indices of 1.33–1.35 and sizes of 60–240 μm. The average absolute error of the refractive index and average relative error of the droplet size are 9.16 × 10−5 and 0.55%, respectively. Experimental validations were carried under laboratory conditions on streams of mondisperse droplets and the robustness of the algorithm was verified under two conditions. In addition to its satisfactory inversion accuracy, the speed of each signal inversion is three times faster than traditional algorithms. The proposed algorithm meets the requirements of engineering applications and scientific research in terms of accuracy and real-time performance. [ABSTRACT FROM AUTHOR]

[Display omitted] • TyG index in normal glucose tolerance (NGT) correlated with composite ISI. • High TyG index in NGT increased the risk of T2DM over an 18-year follow-up. • The predictability of TyG index for T2DM surpassed that of OGTT-derived markers. We explored the role of the triglyceride-glucose (TyG) index as an early and superior predictor of type 2 diabetes mellitus (T2DM) in individuals with normal glucose tolerance (NGT) using a community-based Korean cohort over 18 years. We retrospectively examined 6,072 adults with NGT from the Korean Genome and Epidemiology Study. Cox proportional hazard regression models were employed to evaluate the risk of incidence of T2DM and receiver operating characteristic analysis was used to calculate the area under the curve (AUC). At baseline, the TyG index correlated with the homeostasis model assessment of insulin resistance (HOMA-IR) and the composite insulin sensitivity index (ISI) (β: 0.045, p < 0.001; β: −0.105, p < 0.001, respectively). Over the 18-year follow-up period, 999 individuals developed T2DM. An increase in the TyG quartile independently predicted the incidence of T2DM [hazard ratio, 2.36 (1.9–2.93) for Q4]. The AUC value of the TyG index was 0.642, the highest value among HOMA-IR and OGTT-derived insulin sensitivity and secretion markers. The TyG index is associated with HOMA-IR and composite ISI even with NGT. The TyG index demonstrated independent predictability for T2DM incidence in individuals with NGT, better than OGTT-derived insulin sensitivity and secretion markers. [ABSTRACT FROM AUTHOR]

• Biogenic K-jarosite coatings were synthesized to inhibit pyrite oxidation. • Coated pyrite can resist both chemical and biological oxidation. • Biogenic K-jarosite coatings were stable even when pH < 3. • It is a promising method to prevent AMD production. This study proposes a novel method by forming biogenic K-jarosite coatings on pyrite surfaces driven by Acidithiobacillus ferrooxidans (A. ferrooxidans) to reduce heavy metal release and prevent acid mine drainage (AMD) production. Different thicknesses of K-jarosite coatings (0.7 to 1.1 μm) were able to form on pyrite surfaces in the presence of A. ferrooxidans , which positively correlated with the initial addition of Fe2+ and K+ concentrations. The inhibiting effect of K-jarosite coatings on pyrite oxidation was studied by electrochemical measurements, chemical oxidation tests, and bio-oxidation tests. The experimental results showed that the best passivation performance was achieved when 20 mM Fe2+ and 6.7 mM K+ were initially introduced with a bacterial concentration of 4 × 108 cells·mL−1, reducing chemical and biological oxidation by 70 % and 98 %, respectively (based on the concentration of total iron dissolved into the solution by pyrite oxidation). Similarly, bio-oxidation tests of two mine waste samples also showed sound inhibition effects, which offers a preliminary demonstration of the potential applicability of this method to actual waste rock. This study presents a new perspective on passivating the oxidation of metal sulfide tailings or waste and preventing AMD. [Display omitted] [ABSTRACT FROM AUTHOR]