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To understand biosafety's current situation in laboratory animal research and risk factors affecting occupational health. Compliance surveys were conducted by questionnaire via Questionnaire Star (an application app on the Internet) in Chinese. Thirty-nine anonymous questionnaires were collected. The surveyed institution has established 24 types of ABSL (Animal Biosafety Laboratory) and biosafety management organizations and systems equipped with safety equipment. Our study also suggests that the principal of the laboratory establishment fails to perform supervision and inspection responsibilities, the inappropriate design of the animal biosafety laboratory, non-standardized personnel training and health management, non-strict waste management, and insufficient emergency management. The administrative department and work units should address certain safety and occupational health risks in laboratory animal research. The author proposes control strategies based on organizational guarantee, personnel management, emergency management, etc., to help prevent risks and ensure occupational health. Due to regional limitations and small sample size, the results may not be generalisable to all parts of the world. However, some of the key common issues may also be present in other regions, so we believe that this research still has some relevance.

We synthesized and developed 1,3-dihydro-2H-imidazo[4,5-b]phenazine-2-thione as a ratiometric chemosensor for [Hg.sup.2+] recognition in a DMSO/[H.sub.2]O (v/v = 9:1) binary solution. We rationally introduced the phenazine imidazole group as the fluorophore and the thione moiety as the recognition site to bind [Hg.sup.2+]. Interestingly, the chemosensor showed an ultrasensitive response to [Hg.sup.2+], and the lowest limit of detection was 0.167 nM. In addition, it can also separate [Hg.sup.2+] from aqueous solutions with excellent ingestion capacity, with an adsorption ratio of up to 96%. Furthermore, ion test strips based on chemosensors were fabricated for convenient and efficient detection of [Hg.sup.2+]. Key words: fluorometric, chemosensor, imidazo[4,5-b]phenazine-2-thione, ultrasensitive detection, separation, [Hg.sup.2+]. Nous avons synthetise la 1,3-dihydro-2H-imidazo[4,5-b]phenazine-2-thione afin de mettre au point un capteur chimique ratiometrique pour la reconnaissance des ions [Hg.sup.2+] dans une solution binaire de DMSO/[H.sub.2]O (v/v = 9:1). Nous avons selectionne de maniere rationnelle le groupe imidazophenazine comme fluorophore et le fragment thione comme site de reconnaissance afin qu'il se lie a l'ion [Hg.sup.2+]. Il est interessant de noter que le capteur chimique presente une reponse ultrasensible aux ions [Hg.sup.2+] et une limite inferieure de detection de 0,167 nM. De plus, il permet de separer les ions [Hg.sup.2+] de la solution aqueuse avec une excellente capacite d'ingestion, le rapport d'adsorption atteignant 96 %. En outre, nous avons fabrique des bandelettes d'analyse ioniques permettant de detecter facilement et efficacement les ions [Hg.sup.2+] a l'aide du capteur chimique. [Traduit par la Redaction] Mots-cles : fluorimetrique, capteur chimique, imidazo[4,5-b]phenazine-2-thione, detection ultrasensible, separation, [Hg.sup.2+]., Introduction Recently, ultrasensitive detection has received significant attention owing to its crucial biological, chemical, and environmental applications. (1-5) Over the past few years, numerous methods have been reported for ultrasensitive [...]

With the rapid advancement of robotics technology, an increasing number of researchers are exploring the use of natural language as a communication channel between humans and robots. In scenarios where language conditioned manipulation grounding, prevailing methods rely heavily on supervised multimodal deep learning. In this paradigm, robots assimilate knowledge from both language instructions and visual input. However, these approaches lack external knowledge for comprehending natural language instructions and are hindered by the substantial demand for a large amount of paired data, where vision and language are usually linked through manual annotation for the creation of realistic datasets. To address the above problems, we propose the knowledge enhanced bottom-up affordance grounding network (KBAG-Net), which enhances natural language understanding through external knowledge, improving accuracy in object grasping affordance segmentation. In addition, we introduce a semi-automatic data generation method aimed at facilitating the quick establishment of the language following manipulation grounding dataset. The experimental results on two standard dataset demonstrate that our method outperforms existing methods with the external knowledge. Specifically, our method outperforms the two-stage method by 12.98% and 1.22% of mIoU on the two dataset, respectively. For broader community engagement, we will make the semi-automatic data construction method publicly available at https://github.com/wmqu/Automated-Dataset-Construction4LGM. [ABSTRACT FROM AUTHOR]

The integration of language and vision for object affordance understanding is pivotal for the advancement of embodied agents. Current approaches are often limited by reliance on segregated pre-processing stages for language interpretation and object localization, leading to inefficiencies and error propagation in affordance segmentation. To overcome these limitations, this study introduces a unique task, part-level affordance grounding, in direct response to natural language instructions. We present the Instruction-based Affordance Grounding Network (IAG-Net), a novel architecture that unifies language–vision interactions through a varied-scale multimodal attention mechanism. Unlike existing models, IAG-Net employs two textual–visual feature fusion strategies, capturing both sentence-level and task-specific textual features alongside multiscale visual features for precise and efficient affordance prediction. Our evaluation on two newly constructed vision–language affordance datasets, ITT-AFF VL and UMD VL, demonstrates a significant leap in performance, with an improvement of 11.78% and 0.42% in mean Intersection over Union (mIoU) over cascaded models, bolstering both accuracy and processing speed. We contribute to the research community by releasing our source code and datasets, fostering further innovation and replication of our findings. [ABSTRACT FROM AUTHOR]

OBJECTIVES Ion-adsorption type rare earth ore is extremely important in China and rare in the world. It is China's dominant mineral resource. At present, all the rare earth elements in the existing REE reference materials are oxide minerals, not ion-adsorption type, and cannot be exchanged with strong electrolytes. These reference materials cannot be used to monitor the leaching process of ion-adsorption type REE. METHODS The samples were collected from the typical ion-adsorption type REE weathering crust in Jiangxi Province. After being dried and ball-milled to 200 mesh, they were mixed for 1.5h. The contents of rare earth elements in the ionic phase were analyzed to test the homogeneity by ammonium sulfate leaching and inductively coupled plasma-mass spectrometry (ICP-MS). RESULTS Results showed that the F values for the variance test were less than the threshold, which indicated a good homogeneity. The stability of monitoring samples was tested 4 times in two years, and no statistically significant changes were observed, indicating good stability of the samples. An accurate and reliable leaching analytical method was used in 8 technologically significant laboratories to finalize the contents of ionic phase rare earth elements. The determined values of nine monitoring samples were given by statistical calculation, including weighted average value and total uncertainty results which were from uncertainties in certified values, between-bottle homogeneity and long-term stability. These nine monitoring samples have certified values of 15 ionic phase rare earth elements except Sc. CONCLUSIONS The reference materials can be used to monitor the leaching process and provide metrological support for the analysis of rare earth elements in ionic phase during the evaluation and effective utilization of REE mineral resources.

BACKGROUND Strategic critical metal mineral resources including rare, dispersed, rare earth and platinum group elements play an increasingly critical role in emerging industries such as new materials, new energy and information technology. With the deepening of the geological survey of key mineral resources in China, the critical metal elements present new challenges to analytical techniques due to their complex matrix, large differences in different mineral contents, and unstable chemical properties. OBJECTIVES To introduce recent analytical techniques and applications for critical metal elements in different types of geological samples. METHODS Based on different chemical composition, the main matrices of critical metal elements were classified, mainly divided into silicate, carbonate, sulfate, tungstate, phosphate, oxide, sulfide and halide. For different types of rocks and minerals, chemical digestion was largely carried out by traditional dissolution methods such as the acid dissolution method (nitric acid-hydrofluoric acid combination, aqua regia) or alkali fusion methods. RESULTS The characteristics and application of commonly used instruments including electronic probe microanalyzer, inductively coupled plasma-mass spectrometry, inductively coupled plasma-optical emission spectroscopy, and X-ray fluorescence spectroscopy were reviewed. The problems during critical metal analysis including incomplete dissolution, low recovery, oxides and isobaric interference, inconsistency between samples and standard matrices were reviewed and corresponding solutions were proposed. CONCLUSIONS In situ microanalysis with the advantages of high efficiency, low cost, and high spatial resolution, and field on-site geoanalysis with its simple, fast and close to field work features are the main trends in the development of critical metal elements analytical techniques.

BACKGROUND The accurate determination of ionic phase rare earths in ion-adsorption rare earths is of great significance for the evaluation of rare earth ore bodies. Ionic phase rare earths are adsorbed on clay minerals in the form of hydroxyl or hydrated hydroxyls and can be exchanged and desorbed with strong electrolytes (Mg2+, NH4+, etc.) into solution. The former used ammonium sulfate as the leachate to achieve the desorption and extraction of rare earth ions in the ion phase, but the solution concentration, leaching process and other aspects of choice, leaching rates (60% to 90%) are different. There is no efficient and uniform leaching method conducive to the accurate determination of ionic phase rare earth elements. OBJECTIVES To establish a high-efficiency leaching process by ammonium sulfate solution and determine the accurate contents of ionic-phase rare earth elements. METHODS The leaching parameters (solid-to-liquid ratio, ammonium sulfate concentration, best sample weight, and soaking time) of rare-earth ions by ammonium sulfate were standardized through comparative experiments, which reduced the loss of ionic phase rare earth during leaching. The leaching rates were from 88% to 98%, and ICP-MS was used to accurately determine the ion phase rare earth component. RESULTS The detection limits are 0.05-5.11 ng/g, and the relative standard deviations (RSDs) are 1.80%-10.01% for volcanic rock, 1.06%-7.27% for metamorphic rock, and 1.72%-7.58% for sedimentary rock. CONCLUSIONS The analytical results of the collaborative laboratory verify the reliability and accuracy of the method. This method is easy to operate and has high analysis efficiency. It provides the base for the establishment of relevant industry standards and national standards.

BACKGROUND Os can be separated from the sample matrix by distillation, and the absorbing liquid can be introduced into ICP-MS directly, which is a key step of the molybdenite Re-Os isotopic age analysis. However, the Os signal intensity declines significantly after long time storage. According to the properties of OsO4, the possible causes may include:1) volatilization which reduces the Os content in the absorbing liquid, and 2) the reduction in which Os(Ⅷ) transforms to the low valence state without volatility and OsO4 in the gas state decreases. Although they can both reduce the Os being introduced into ICP-MS ultimately, the extent of their effect is not clear. OBJECTIVES To quantify the effects of absorbing liquid storage conditions such as duration, acidity and temperature on the Os signal intensity, to identify the cause of this decline and to find out the methods for its suppression. METHODS:The experiment consists of two parts:1) using the molybdenite Re-Os dating reference materials to construct a different absorbing liquid storage condition series, including duration, acidity and temperature, and measure their Os signal intensities in terms of 187Os/193Ir relative ratios. 2) sealing the residual absorbing liquid together with the spike and oxidizing agents within the Carius tube with sequent heating and distillation. The 187Os/190Os ratios were determined to calculate the Os content and the retention rate. RESULTS After storing, the Os signal intensities of absorbing liquids decline with time from 3.2% to 68.6%. The longer time, the lower acidity and the higher temperature for OsO4 absorbing liquid storage, the more obvious Os signal declines. After storing at room temperature for the same time, the Os retention rate of the low-acidity series is higher than that of the high-acidity series, but the former has a lower signal intensity than the latter. This indicates that both volatilization and reduction contribute to the decline of Os signal intensity and are the main factors. CONCLUSIONS Freezing to -18℃ can inhibit the volatilization of OsO4, whereas increasing the acidity (about 3.5 mol/L) can reduce OsO4 reduction. The combination of the two inhibits signal attenuation, and increases the flexibility and applicability of the distillation method.

Aiming at the shortcomings of the existing methods to detect the security flaws that have complex structures,a new analysis model and its application method was proposed.First,analysis models based on key information of code structures extracted from path subsets of characteristic element sets that are generated by source code element sets of code security flaws were constructed.Then the analysis model according to the statistical probability of each kind of IR statement was calculated,and the IR code group which matched the feature model was found.Finally,through the translating relation between binary codes and IR codes,various code security flaws of binary program were found out.The analysis models can be applied to both common single-process binary programs and binary parallel programs.Experimental results show that compared with the existing methods,the application of the analysis model can be more comprehensive and in-depth in detecting various types of complex binary code security flaws with higher accuracy.

Graphite has relatively high Re and Os contents and is an ideal mineral for Re-Os isotope dating. However, there are few studies on Re-Os dating of graphite. Particularly for the graphite which was formed by deformation of coal beds, the variation in Re-Os isotope system needs further study. The Lutang graphite deposit in Hunan is one of the typical cryptocrystalline graphite deposits in China. The ore-bodies are hosted in coals of the Permian Longtan Formation. In this study, the Re-Os isotopic compositions of the graphite samples from Lutang deposit and the raw coal samples from the peripheral area were analyzed by digesting sample in the Carius tube, direct distilling Os from the Carius tube, extracting Re by acetone and determining Re and Os isotopes by Negtive Thermal Ionization Mass Spectrometry. The results indicate that the Re and Os contents are 0.901-9.794 ng/g and 7.3-189.5 pg/g, respectively. The Re-Os isotope isochron age is 155.6±3.6 Ma, which is consistent with the zircon U-Pb age (153-157 Ma) of StageⅡ medium-grained biotite granite of the Qitianling pluton on the east side of the deposit. It also indicates that the coal seam of the Longtan Formation is subjected to 'baking' by the Qitianling pluton, inducing the hot contact metamorphism and changing the raw coal near the Qitianling pluton to graphite to form a graphite deposit. The comparison of Re and Os content and Os isotopic composition between the graphite, coal and Qitianlign pluton demonstrates that the Re and Os in the graphite are mainly derived from raw coal. According to the initial Os isotope ratio of 0.686±0.032, it can be concluded that minor Os with low 187Os/188Os value was absorbed by carbonaceous material during the intrusion of coal seam by the Qitianling pluton.

Volcanic rocks in the Xiemisitai Mountains, in Northwest Junggar were recently considered to form in the Silurian rather than the Devonian period. However, the characteristic and tectonic setting of Middle Silurian volcanic rocks in this area are poorly constrained. In this study, major and trace elements and Sr-Nd-Os isotopic composition analyses were synthetically conducted on the Middle Silurian basalt and basaltic andesite in northwest of the Xiemisitai Mountains, West Junggar. These volcanic samples are characterized by high MgO (5.15%-7.81%) with Mg of 56.0-60.7, low CaO (4.56%-5.09%) and FeOT/MgO (1.15-1.40), similar to those of high-Mg volcanic rocks. Basalts have εNd(t) of 2.65, (87Sr/86Sr)i of 0.70439, and (187Os/188Os)i of 0.4901. The slightly enriched isotopic signatures, high Th/Yb (2.2-2.7) and low Ba/La (17.4-33.4) indicate that they originated from depleted mantle metasomatized by melts from subducted sediments and suffered from crustal contamination. The volcanic rocks are calc-alkaline and exhibit arc-like geochemistry with the enrichment of light REE and large ion lithophile elements. It is suggested that these rocks were probably formed in a back-arc setting due to northward subduction of the Junggar Oceanic slab.