Natural Samples Research Articles

Chemical characteristics and health risk evaluation of natural waters in the Du River Source National Nature Reserve: A case study in Zhushan County, Hubei Province, China

To study the distribution of trace elements in natural water of the Du River Source National Nature Reserve and to assess the water quality and health risks, Zhushan County in Hubei Province was selected as the study area. Element content in 361 natural water samples collected from Zhushan County were measured by ICP-MS, ICP-OES, and HG-AFS. The main anions and cations present in water samples from Zhushan County are Ca2+ and HCO3−. The water chemistry is predominantly influenced by the weathering of carbonate rocks. The water samples with high content of selenium (Se) (0∼82.9 μg/L, mean 4.6 μg/L) in natural water in Zhushan County are mainly distributed in the northern part of Zhushan. The strontium (Sr) content of 49.6% of the water samples (0.001–2.177 mg/L, mean 0.234 mg/L) reached the criteria of natural mineral water for drinking in China (Sr ≥ 0.2 mg/L), which is distributed throughout the county. The high content of metasilicic acid (H2SiO3) (0.026–35.910 mg/L, mean 12.598 mg/L) and zinc (Zn) (0∼407.218 μg/L, mean 12.406 μg/L) are concentrated in northern Zhushan County. 99.7% water samples were freshwater and 98.9% meet the criteria of “good” water quality. All of the natural water samples have low health risk and low heavy metal pollution. 6.1% water samples meet the criteria of Se-type mineral water, while 45.4% meet the criteria of Sr-type mineral water, and 4.4% water samples meet the criteria of “low sodium, high Se, and high Sr” mineral water. Zhushan County has the potential for Se-type mineral water and Sr-type mineral water development. The findings of this study hold immense significance for the public health implications of drinking water in Du River Source, thereby offering valuable insights for effective water resources management.

Contribution of abiotic methane polymerization of C2+ hydrocarbons in highly mature natural gas reservoirs

The formation and evolution of thermogenic gases were investigated using a combination of intermolecular and intramolecular isotope analyses of 32 natural gas samples collected from the Sichuan and Tarim basins (China) and the Arkoma Basin (USA). Three evolution stages (I–III) were identified: In stage I, hydrocarbon gases are produced through thermal decomposition of organic matter, and kinetic isotope effects in C–C bond breakage control their isotopic distributions; In stage II, C2–C5 hydrocarbons crack with increasing thermal maturity, with their formation and decomposition tending toward thermodynamic equilibrium, and at the end of this stage, the intermolecular and intramolecular isotopic compositions of gaseous hydrocarbons are in thermodynamic equilibrium; A remarkable feature of stage III is the surface-catalyzed abiotic polymerization of methane, which provides a critical origin of C2+ hydrocarbons in this stages and leads to isotopic anomalies in C2+ hydrocarbons, including the reversal of δ13C distributions of C1–C3 and the reverse evolution trend of SP value of propane (i.e., tending to be positive). The contribution of C2+ hydrocarbons from the abiotic polymerization of methane can be determined based on a two-end member model. C2+ hydrocarbons in the Changning shale gases are all generated from abiotic methane polymerization, and the contribution ratio in the Weiyuan shale gases is about 85 %, while, the contribution of C2+ hydrocarbons in dry gases from the Tarim Basin formed by this way is no more than 55 %. High methane abundance, high temperature, and abundant catalyst are beneficial to abiotic methane polymerization.

Calibration‐free image analysis method for grain‐size distribution of small natural sand samples

AbstractNatural sand samples collected from bedload or suspension transport can be too small to be sieved. However, related transported mass to sediment size is crucial to calibrate sediment transport models. Image analysis technique can be an easy and cheap alternative. The present study proposes a general law valid for natural sand grains and small gravels that statistically relates elongation to flatness of particles and gives after some assumptions on grain shape and orientation of grains at the sieve mesh passage, the closest distribution of mass to sieving technique from images of grains given by a flatbed scanner. The proposed model is based on the hypothesis of an ellipsoidal grain shape and a preferential grain crossing aligned with the sieve diagonal. Any sand either homogeneous or heterogeneous from various origins (fluvial, marine and quarry) can be analysed directly without any further need for calibration.

Rapid detection of virulence-related genes by multiplex PCR in five pathogenic bacteria of mulberry bacterial wilt

Mulberry bacterial wilt is a devastating disease that is difficult to control and causes serious economic losses to the sericulture industry. This disease is mostly caused by a diverse group of pathogenic and opportunistic bacteria including, Ralstonia pseudosolanacearum, Pantoea ananatis, Enterobacter cloacae complex (ECC), Klebsiella pneumoniae species complex (KpSC), and K. oxytoca complex (KoC). Due to the lack of a rapid and reliable test to simultaneously detect these complex pathogens of mulberry wilt, we developed a multiplex PCR (mPCR) assay to detect five virulence-related genes carried by the pathogenic bacteria of mulberry bacterial wilt disease. The primers were designed for the virulence-related genes: pleD (GGDF structural domain-containing protein), yjfP (esterase), pelY (peripheral pectate lyase), ampD (N-acetyl-anhydromuranmyl-L-alanine amidase), and ripW (type III effector). Overall, the developed mPCR assay showed highly specific, sensitive and reproducible detection of target pathogens. Briefly, the results showed that the mPCR was highly specific in individual reactions, and the lowest detection concentration of the five pathogenic bacteria was 1.87 × 103 CFU/mL (DNA = 2.45 pg/μL). From 46 natural mulberry wilt samples, the mPCR detection rates of P. ananatis, ECC, KpSC, KoC and R. pseudosolanacearum were 8.69, 91.3, 34.7, 23.9 and 65.21%, respectively. The traditional culture media isolation methods showed comparable results. The pathogenicity test of 84 suspected pathogenic bacteria revealed that the morbidity (average morbidity level) caused by the pathogenic bacteria detected by mPCR was ≥ 65.5%, while the morbidity of the undetected pathogenic bacteria was ≤ 35.5%. Based on these results, we believe that the mPCR developed in the present study will be useful in rapid, reproducible, and sensitive detection of the pathogenic bacteria causing mulberry bacterial wilt including, R. pseudosolanacearum, P. ananatis, ECC, KpSC, and KoC.Graphical abstract

Matrix-free laser desorption/ionization mass spectrometry imaging for rapid evaluation of wood biomass conversion.

This study overcomes traditional biomass analysis limitations by introducing a pioneering matrix-free laser desorption/ionization (LDI) approach in mass spectrometry imaging (MSI) for efficient lignin evaluation in wood. The innovative acetic acid-peracetic acid (APA) treatment significantly enhances lignin detection, enabling high-throughput, on-site analysis. Wood slices, softwood from a conifer tree (Japanese cypress) and hardwood from a broadleaf tree (Japanese beech), were analyzed using MSI with a Fourier transform ion cyclotron resonance mass spectrometer. The developed APA treatment demonstrated effectiveness for MSI analysis of biomass. Our imaging technique successfully distinguishes between earlywood and latewood and enables the distinct visualization of lignin in these and other wood tissues, such as the radial parenchyma. This approach reveals significant contrasts in MSI. It has identified intense ions from β-O-4-type lignin, specifically in the radial parenchyma of hardwood, highlighting the method's precision and utility in wood tissue analysis. The benefits of matrix-free LDI include reduced peak overlap, consistent sample quality, preservation of natural sample properties, enhanced analytical accuracy, and reduced operational costs. This innovative approach is poised to become a standard method for rapid and precise biomass evaluation and has important applications in environmental research and sustainable resource management and is crucial for the effective management of diverse biomass, paving the way towards a sustainable, circular society.

Mechanical and Environmental Analysis of Granular Subbase with Fine Crumb Rubber

AbstractThe increasing manufacturing of tires, driven by the automotive sector, has led to various sustainability and waste management issues. Consequently, it is necessary to explore alternatives for the reuse of these wastes. Rubber has demonstrated properties that could make it an attractive material for use as a granular aggregate. The aim of this study is to evaluate the influence of crumb rubber (CR) on the mechanical behavior of a granular subbase (GSB) by replacing fine CR at 10% and 15%. An environmental analysis of the proposal was conducted using the SimaPro tool, and a series of laboratory tests were performed to assess physical and mechanical characteristics. The strength results indicate a decreasing trend as the CR content in the GSB increases. Specifically, in abrasion tests, the natural material showed an average result of 30.86%, while the mixes with 10% and 15% CR exceeded the maximum limit (50%), achieving results of 59.24% and 53.98%, respectively. In terms of the California Bearing Ratio (CBR), only the natural samples compacted at maximum energy exceeded the minimum requirements for low and medium traffic levels (30%). The highest CBR value for samples containing CR was 5%, whereas the natural GSB reached a maximum CBR of 33%. A similar trend is observed in environmental outcomes, with increases of up to 17% in abiotic depletion for the sample with 15% CR. Overall, the environmental analysis suggests that incorporating CR into the GSB could lead to an increase in various environmental impacts.

Interactive learning of natural sign language with radar

AbstractOver the past decade, there have been great advancements in radio frequency sensor technology for human–computer interaction applications, such as gesture recognition, and human activity recognition more broadly. While there is a significant amount of study on these topics, in most cases, experimental data are acquired in controlled settings by directing participants what motion to articulate. However, especially for communicative motions, such as sign language, such directed data sets do not accurately capture natural, in situ articulations. This results in a difference in the distribution of directed American Sign Language (ASL) versus natural ASL, which severely degrades natural sign language recognition in real‐world scenarios. To overcome these challenges and acquire more representative data for training deep models, the authors develop an interactive gaming environment, ChessSIGN, which records video and radar data of participants as they play the game without any external direction. The authors investigate various ways of generating synthetic samples from directed ASL data, but show that ultimately such data does not offer much improvement over just initialising using imagery from ImageNet. In contrast, an interactive learning paradigm is proposed by the authors in which model training is shown to improve as more and more natural ASL samples are acquired and augmented via synthetic samples generated from a physics‐aware generative adversarial network. The authors show that the proposed approach enables the recognition of natural ASL in a real‐world setting, achieving an accuracy of 69% for 29 ASL signs—a 60% improvement over conventional training with directed ASL data.

Hg Content Characteristics and Safe Planting Zoning of Paddy Soil and Rice in Guizhou Province

Guizhou Province ranks first in terms of Hg reserves and production in the country, and rice is its largest grain crop. In order to study the characteristics and pollution causes of soil-rice Hg content at the provincial level in Guizhou and to carry out safe planting zoning, 1 564 pairs of soil-rice samples, 470 natural soil samples, and 203 individual paddy soil samples were collected to test their Hg content and basic physical and chemical properties of the soil. The results showed that:① Paddy soil was mainly neutral and acidic, the paddy soil ω (Hg) range was 0.005-93.06 mg·kg-1, and the geometric mean was 0.864 mg·kg-1. The Hg content of paddy soil in Guizhou Province was significantly higher than that in natural soil (0.16 mg·kg-1,P < 0.05). Compared with the filtered value and control value, the soil samples exceeded the standard by 63.25% and 14.71%, respectively. Among them, the soil Hg pollution in Danzhai County of Qiandongnan Prefecture, Wuchuan County of Zunyi City, Zhenfeng County of Qianxinan Prefecture, and Wanshan District of Tongren City was more prominent. ② Rice ω(Hg) ranged from 0.000 5 to 0.52 mg·kg-1, and the geometric mean was 0.010 mg·kg-1, the percentage of rice Hg content exceeding the standard was 25.87%, and the exceeding points were mainly distributed in Suiyang County of Zunyi City, Zhenfeng County of Qianxinan Prefecture, Xixiu District of Anshun City, Bijiang District of Tongren City, and other industrial and mining activity-intensive areas. ③ The majority of the study area was in the priority protection category (74.75%); the safe use category accounted for (24.62%); and the strictly controlled category (0.93%) was scattered in Danzhai County at the border between Qiannan Prefecture and Qiandongnan Prefecture, Zhenfeng County in Qianxinan Prefecture, and Wanshan District in Tongren. It is not recommended to plant rice, which can be used as feed for reproduction.

Thermo‐physical characterisation of natural rocks and impact analysis of variations in their thermo‐physical properties on thermal storage performance

AbstractIn this study, the thermal characterisation of natural rock samples from Zimbabwe for low‐temperature industrial thermal energy storage (TES) applications was carried out. Thermal stability, specific heat capacity, thermal diffusivity, thermal conductivity and density were determined. Variations in these parameters were evaluated and their impact on thermal storage performance was analysed. Basalt and dolerite samples from different locations were found to have average specific heat capacities of 826 and 853 J/kg K, respectively, at room temperature. Insignificant variations were observed with differences of 3.4% for basalt and 1.7% for dolerite samples. Also, negligible differences of 0.3% and 0.7% in densities for rocks of the same type but of different origins were obtained for basalt and dolerite samples, respectively. However, significant variations in thermal diffusivity of all the igneous and metamorphic samples were observed with quartzite rock exhibiting the highest value of 2.1 × 10−6 m2/s, while the values for the other samples range from 0.9 × 10−6 to 1.6 × 10−6 m2/s. This implies that the thermal efficiency of sensible TES systems that use different or the same rock types from different locations can be significantly high to be overlooked. Thermo‐gravimetric analysis results revealed that the rock samples studied have good thermal stability for low‐temperature heat storage applications.

Observationally constrained regional variations of shortwave absorption by iron oxides emphasize the cooling effect of dust

Abstract. The composition of soil dust aerosols derives from the mineral abundances in the parent soils that vary across dust source regions. Nonetheless, Earth system models (ESMs) have traditionally represented mineral dust as a globally homogeneous species. The growing interest in modeling dust mineralogy, facilitated by the recognized sensitivity of the dust climate impacts to composition, has motivated state-of-the-art ESMs to incorporate the mineral speciation of dust along with its effect upon the dust direct radiative effect (DRE). In this work, we enable the NASA Goddard Institute for Space Studies ModelE2.1 to calculate the shortwave (SW) DRE accounting for the regionally varying soil mineralogy. Mineral–radiation interaction at solar wavelengths is calculated according to two alternative coupling schemes: (1) external mixing of three mineral components that are optically distinguished, one of which contains embedded iron oxides; (2) a single internal mixture of all dust minerals with a dynamic fraction of iron oxides that varies regionally and temporally. We link dust absorption to the fractional mass of iron oxides based on recent chamber measurements using natural dust aerosol samples. We show that coupled mineralogy overall enhances the scattering by dust, and thus the global cooling, compared to our control run with globally uniform composition. According to the external mixing scheme, the SW DRE at the top of atmosphere (TOA) changes from −0.25 to -0.30Wm-2, corresponding to a change in the net DRE, including the longwave effect, from −0.08 to -0.12Wm-2. The cooling increase is accentuated when the internal mixing scheme is configured: the SW DRE at the TOA becomes -0.34Wm-2 with a net DRE of -0.15Wm-2. The varying composition modifies the regional distribution of single scattering albedo (SSA), whose variations in specific regions can be remarkable (above 0.03) and significantly modify the regional SW DRE. Evaluation against the AErosol RObotic NETwork (AERONET) shows that explicit representation of soil mineralogy and its regional variations reduces the low bias of model dust SSA while improving the range of variability across stations and calendar months. Despite these improvements, the moderate spatiotemporal correlation with AERONET reveals remaining modeling challenges and the need for more accurate measurements of mineral fractions in soils.

Determination of the internal structural heterogeneity of natural diamond: Methodological aspects of using confocal Raman spectroscopy with polarization analysis

Aim. To describe a technique for studying the internal structural heterogeneity of natural diamond crystals, based on confocal Raman spectroscopy with polarization analysis, including angular resolution, at high spectral (0.5–0.6 cm–1) and spatial (1 μm) resolution. Results. The parameters of the F2g vibrational mode in diamond (position, width, intensity, shape, including the Gaussian and Lorentzian contributions to the broadening) are determined by the superposition influence of a number of factors, including the type and content of structural stresses, deformations, various types of defects, as well as orientation of crystallographic axes of the crystal relative to the directions of incident and scattered rays and the directions of their electric polarization vectors. The proposed analytical technique includes: (1) analysis of the crystallographic orientation of the sample in the spectrometer coordinate system and possible misorientations of its fragments with an error of ≈8–15°; (2) visualization of the distribution of structural stresses, deformations, twins, impurity defects and their associates based on sample surface mapping by spectral parameters of the F2g vibration mode; (3) obtaining statistical characteristics of the internal structural heterogeneity of the samples based on diagrams of spectral parameter frequency with a statistically significant number (≈103): unimodality (uni-, bimodal distributions) and distribution dispersion (from ≈0.1 to ≈0.6 cm–1 for width and from ≈0.04 to ≈0.6 cm–1 for line position). The procedure was tested using two synthetic CVD diamond single crystals doped with nitrogen and boron. The possibility of typification of natural samples by statistical characteristics of internal heterogeneity is considered using the example of samples from kimberlite pipes of Yakutia and placers of the Western Cis-Urals. Conclusions. A method for determining the internal structural heterogeneity of natural diamond crystals based on confocal Raman spectroscopy with polarization analysis is proposed. The possibility of using statistical characteristics of heterogeneity as a typomorphic feature of the original diamond source is demonstrated. The proposed diagrams are promising for sample comparison and typification.

Design of ESIPT-Based Fluorescent Probes for Dual-Mode Sensing of Cyanide: Application to Rapid On-Location Detection and Screening of Natural Water Samples

Design of ESIPT-Based Fluorescent Probes for Dual-Mode Sensing of Cyanide: Application to Rapid On-Location Detection and Screening of Natural Water Samples

Pre-hospital glycemia as a biomarker for in-hospital all-cause mortality in diabetic patients - a pilot study

BackgroundType 2 Diabetes Mellitus (T2DM) presents a significant healthcare challenge, with considerable economic ramifications. While blood glucose management and long-term metabolic target setting for home care and outpatient treatment follow established procedures, the approach for short-term targets during hospitalization varies due to a lack of clinical consensus. Our study aims to elucidate the impact of pre-hospitalization and intra-hospitalization glycemic indexes on in-hospital survival rates in individuals with T2DM, addressing this notable gap in the current literature.MethodsIn this pilot study involving 120 hospitalized diabetic patients, we used advanced machine learning and classical statistical methods to identify variables for predicting hospitalization outcomes. We first developed a 30-day mortality risk classifier leveraging AdaBoost-FAS, a state-of-the-art ensemble machine learning method for tabular data. We then analyzed the feature relevance to identify the key predictive variables among the glycemic and routine clinical variables the model bases its predictions on. Next, we conducted detailed statistical analyses to shed light on the relationship between such variables and mortality risk. Finally, based on such analyses, we introduced a novel index, the ratio of intra-hospital glycemic variability to pre-hospitalization glycemic mean, to better characterize and stratify the diabetic population.ResultsOur findings underscore the importance of personalized approaches to glycemic management during hospitalization. The introduced index, alongside advanced predictive modeling, provides valuable insights for optimizing patient care. In particular, together with in-hospital glycemic variability, it is able to discriminate between patients with higher and lower mortality rates, highlighting the importance of tightly controlling not only pre-hospital but also in-hospital glycemic levels.ConclusionsDespite the pilot nature and modest sample size, this study marks the beginning of exploration into personalized glycemic control for hospitalized patients with T2DM. Pre-hospital blood glucose levels and related variables derived from it can serve as biomarkers for all-cause mortality during hospitalization.

Postprocessing Workflow for Laboratory Diffraction Contrast Tomography: A Case Study on Chromite Geomaterials.

Texture stands as a fundamental descriptor in the realms of geology and earth and planetary science. Beyond offering insights into the geological processes underlying mineral formation, its characterization plays a pivotal role in advancing engineering applications, notably in mining, mineral processing, and metal extraction, by providing quantitative data for predictive modeling. Laboratory diffraction contrast tomography (LabDCT), a recently developed 3D characterization technique, offers nondestructive measurement of grain phases including their morphology, distribution, and crystal orientation. It has recently shown its potential to assess 3D textures in complex natural rock samples. This study looks at improving on previous work by examining the artifacts and presents a novel postprocessing workflow designed to correct them. The workflow is developed to rectify inaccurate grain boundaries and interpolate partially reconstructed grains to provide more accurate results and is illustrated using multi-scan examples on chromite sands and natural chromitite from the Upper Group 2 Reef layer in South Africa. The postcorrected LabDCT results were validated through qualitative and quantitative assessment using 2D electron back-scattered diffraction on polished sample surfaces. The successful implementation of this postprocessing workflow underscores its substantial potential in achieving precise textural characterization and will provide valuable insights for both earth science and engineering applications.

Supramolecular solvent-based liquid–liquid microextraction (SUPRAS-LLME) of Sudan dyes from food and water samples with HPLC

Utilizing the environmentally friendly technique of supramolecular solvent-based microextraction (SUPRAS-LLME), Sudan I-IV dyes were successfully isolated and enriched from food and natural water samples. The optimization of the microextraction process was carried out by studying the effects of various parameters such as pH (6.0), supramolecular volume (100 μL), tetrahydrofuran (THF) volume (200 μL), ultrasonication temperature (40 °C), and vortex time (1.0 min). Extraction efficiency ranged between 82 % and 109 %, while other analytical parameters such as the limits of detection (LOD) were determined to be 0.23, 0.51, 0.42, and 0.39 μg L−1 for Sudan I, II, III, and IV, respectively. The total figure of merits for the presented SUPRAS-LLME method includes a limits of quantification (LOQ) of 0.78, 1.70, 1.41, and 1.30 μg L−1, a relative standard deviation (RSD%) of 3.4, 6.1, 2.9, and 4.4 (n = 10), a linear range of 5–1000 μg L−1 for all Sudan dyes, a pre-concentration factor (PF) of 15, 10, 10, and 17, and a determination coefficient (R2) of 0.9994, 0.9965, 0.9955, and 0.9946, for Sudan I, II, III, and IV, respectively. The environmental friendliness of the method was confirmed by evaluating the greenness of the method with the AGREE metric tool. A sustainable and environmentally friendly option for the extraction of Sudan dyes from food and water samples is offered by this SUPRAS-LLME method.

Analysis of the modification of piping channels on kaolinitic clayey samples in the pinhole test

Dispersivity is a severe pathology that occurs mainly in clay soils and is usually catastrophic in geotechnical structures susceptible to this damage. Hundreds of dams worldwide have failed due to quality problems, mainly by piping in the body, foundation, spillway, culvert, and other peripheral structures. The pinhole test is currently considered the most accurate test for detecting the dispersivity of clay soils. However, it presents problems when objectively evaluating the dispersivity of a material due to the qualitative nature of the estimation of results. In particular, the methodology for determining turbidity has been identified. This document studies different piping paths in the sample, which a priori may be more realistic than the single path in the current test. A kaolinitic clay, widely studied through index and mineralogical tests, is used as the base material. Regarding the detection of dispersivity, a specialized test package was used to reduce the uncertainty of the results. Natural samples were analyzed using ASTM D4647-13. A modification of the pinhole test was proposed based on the imposition of additional artificial channels. The results revealed that this modification can make the test more realistic because when the dispersive front advances in the soil, it does not travel along a single path but instead looks for different erosive paths. The details of this assertion are discussed throughout the paper.

Abstract PO1-05-11: Efficacy of metformin as adjunctive therapy in patients with de novo metastatic breast cancer: a retrospective cohort study

Abstract Background: Metformin, an oral biguanide used for the treatment of type-2 diabetes mellitus (DM), has been shown in a considerable number of studies to have an anti-tumorigenic impact against breast cancer cells through several mechanisms,thereby improving breast cancer outcomes. However, the impact of metformin treatment on survival outcomes in patients with non-diabetic breast cancer is still under debate, with very few data available regarding metformin administration in de novo metastatic breast cancer (dnMBC). This study was conducted to investigate and evaluate the impact on survival outcomes of patients with dnMBC treated with metformin as adjunctive therapy at our institutes. Methods: All dnMBC women who received chemotherapy-based systemic therapy or combined with metformin administered orally in our hospitals between March 2007 and November 2016 were enrolled in the study. Data were retrospectively extracted from the patients’case records. Data were analyzed according the clinicopathological features and treatment outcomes. All specimens were rechecked for the purpose of the research. Overall survival (OS), as the study endpoint, was defined as the time from pathologically confirmed diagnosis to all-cause death or end of the follow-up time.Kaplan-Meier estimate was used to calculate the survival rates.The difference between metformin and non-metformin groups was compared by the log-rank method.Cox regression analysis (uni-and multivariate analysis) was used to assess the effect of variables on survival outcomes.Analyses were performed by Stata 17 software for windows version. Results: A total of 252 women with dnMBC were included with an average age of 54.41±11.61 years. Among them, 97 patients (including 11 DM patients) received chemotherapy-based systemic therapy plus oral administration of metformin 850-1000mg twice daily (metformin group), and 155 patients received chemotherapy-based systemic therapy (non-metformin group). There was no significant difference in body mass index, age, N-stage, P53 index, ER/PR status, HER-2 expression and initial metastatic sites between metformin group and non-metformin group. But there were differences in T-stage and Ki67 index between the two groups (Table 1). The median follow-up was 70 months.The median OS was 24 months.The 3-year and 5-year OS rates for all patients were 29.8% (95% CI:24.2% to 35.4%) and 11.6% (95% CI:7.5% to 16.7%),respectively; Log-rank test showed that the metformin group had a significant advantage over the non-metformin group in OS rates(p=0.0002).The 3-year and 5-year OS rates in the metformin group were 42.3% (95% CI:32.4% to 51.8%) and 21.2% (95% CI:12.8% to 31.1%), respectively; the same rates for non-metformin group were 21.9% (95% CI: 15.8% to 28.7%) and 5.6% (95% CI: 2.4% to 11.1%), respectively. Results of proportional hazards model, after adjustment for T-stage and Ki67 index, depicted an independent prognostic value of metformin use with multivariate hazard ratio of 0.61 (95% CI: 0.45 to 0.81) for OS compared to non-metformin group (p=0.001).No survival advantage was found for DM patients (0.59;95% CI:0.29 to 1.22; p=0.159). Conclusions: Our data support a favorable outcome for survival associated with metformin use in dnMBC patients. However, the retrospective nature and small sample size of the current study are major limitations to reliable conclusions about metformin's potential to improve OS in patients. Therefore, prospective evidence from phase-3 randomized controlled trials on the feasibility of metformin use in dnMBC is required before its routine use can be recommended. Keywords: Metformin; De novo metastatic breast cancer; Adjunctive therapy; Survival outcomes Citation Format: Ren Chongxi, Sun Jianna, Kong Lingjun, Hongjun Yu. Efficacy of metformin as adjunctive therapy in patients with de novo metastatic breast cancer: a retrospective cohort study [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO1-05-11.

A facile electrochemical aptasensor for chloramphenicol detection based on synergistically photosensitization enhanced by SYBR Green I and MoS2

This study described the development of a photocatalytic electrochemical aptasensor for the purpose of detecting chloramphenicol (CAP) antibiotic residues in water by utilizing SYBR Green I (SG) and chemically exfoliated MoS2 (ce-MoS2) as synergistically signal-amplification platforms. The Au nanoparticles (AuNPs) were electrodeposited onto the surface of an indium tin oxide (ITO) electrode. After that, the thiolate-modified cDNA, also known as capture DNA, was combined with the aptamer. Subsequently, photosensitized SG molecules and ce-MoS2 nanomaterial were inserted into the groove of the resultant double-stranded DNA (dsDNA). The activation of the photocatalytic process upon exposure to light resulted in the generation of singlet oxygen. This singlet oxygen effectively splits the double-stranded DNA, resulting in a significant enhancement in the current of [Fe(CN)6]3-/4-. When the CAP was present, both SG molecules and ce-MoS2 broke away from the double-stranded DNA, which turned off the photosensitization response, leading to a significant decrease in the current of [Fe(CN)6]3-/4-. Under optimal conditions, the aptasensor exhibited a linear relationship between CAP and logarithmic concentrations from 20 to 1000 nM, with a detection limit (3σ) of 3.391 nM. The aptasensor also demonstrated good selectivity towards CAP in the presence of interfering antibiotics such as tetracycline, streptomycin, levofloxacin, ciprofloxacin, and sulfadimethoxine. Additionally, the results obtained from the analysis of natural water samples using the proposed aptasensor were consistent with the findings acquired through the use of a liquid chromatograph-mass spectrometer. Therefore, with its simplicity and high sensitivity, this biosensor can potentially detect alternative antibiotics in environmental water samples by replacing the aptamers based on photosensitization.

Are minimally verbal autistic children's modality and form of communication associated with parent responsivity?

Prior work examined how minimally verbal (MV) children with autism used their gestural communication during social interactions. However, interactions are exchanges between social partners. Examining parent-child social interactions is critically important given the influence of parent responsivity on children's communicative development. Specifically, parent responses that are semantically contingent to the child's communication plays an important role in further shaping children's language learning. This study examines whether MV autistic children's (N = 47; 48-95 months; 10 females) modality and form of communication are associated with parent responsivity during an in-home parent-child interaction (PCI). The PCI was collected using natural language sampling methods and coded for child modality and form of communication and parent responses. Findings from Kruskal-Wallis H tests revealed that there was no significant difference in parent semantically contingent responses based on child communication modality (spoken language, gesture, gesture-speech combinations, and AAC) and form of communication (precise vs. imprecise). Findings highlight the importance of examining multiple modalities and forms of communication in MV children with autism to obtain a more comprehensive understanding of their communication abilities; and underscore the inclusion of interactionist models of communication to examine children's input on parent responses in further shaping language learning experiences.

Establishing freshwater sediment sample pretreatment methods for monitoring microplastics and its challenges

Microplastics (MPs) have been detected in various environmental matrices, drinking water, and food, and their presence is an ecological and human health concern. Most research on MPs has focused solely on their detection and analysis. However, sample pretreatment methods are critical for accurate MP analysis and must be properly established. In particular, freshwater sediment contains more impurities than other environment samples, thus requiring more elaborate sample pretreatment. Therefore, research on this media and corresponding pretreatment needs to be performed. Herein, we present a sample pretreatment method for analyzing MPs in freshwater sediments. Detailed factors in arriving at this pretreatment process were evaluated and discussed. Using this established pretreatment method, a total average recovery of six types of standard MPs (HDPE, LDPE, PS, PP, PET, and PVC) for sizes of 100 µm, 20–100 µm, and 1–20 µm was 94.0 %, 90.2 %, and 82.5 %, respectively. After recovery validation, a modular pretreatment device was developed and combined with the established pretreatment method. The developed device performs density separation and organic matter removal, resulting in about 80 % recovery of standard MPs. In addition, natural freshwater sediment samples were prepared using an established pretreatment method, and MPs in streams were analyzed using FTIR, TED-GC–MS, and Pyr-GC–MS. The device affords a low-cost, simple, efficient tool for sample pretreatment steps and easy MP recovery. Thus, it has great potential to simplify sample pretreatment steps for easy MP monitoring, especially for freshwater sediment samples.