An automated method for stem diameter measurement based on laser module and deep learning

Abstract Background Measuring stem diameter (SD) is a crucial foundation for forest resource management, but current methods require expert personnel and are time-consuming and costly. In this study, we proposed a novel device and method for automatic SD measurement using an image sensor and a laser module. Firstly, the laser module generated a spot on the tree stem that could be used as reference information for measuring SD. Secondly, an end-to-end model was performed to identify the trunk contour in the panchromatic image from the image sensor. Finally, SD was calculated from the linear relationship between the trunk contour and the spot diameter in pixels. Results We conducted SD measurements in three natural scenarios with different land cover types: transitional woodland/shrub, mixed forest, and green urban area. The SD values varied from 2.00 cm to 89.00 cm across these scenarios. Compared with the field tape measurements, the SD data measured by our method showed high consistency in different natural scenarios. The absolute mean error was 0.36 cm and the root mean square error was 0.45 cm. Our integrated device is low cost, portable, and without the assistance of a tripod. Compared to most studies, our method demonstrated better versatility and exhibited higher performance. Conclusion Our method achieved the automatic, efficient and accurate measurement of SD in natural scenarios. In the future, the device will be further explored to be integrated into autonomous mobile robots for more scenarios

Characteristics and controlling factors of the present geothermal field in the Songliao Basin

Objective The geothermal field in the present sedimentary basin is a result of the energy balance between various dynamic processes on the Earth. It serves as an important tool for understanding continental dynamics, such as tectonic deformation and the evolution of the continental lithosphere. Additionally, it provides the basis for evaluating regional geothermal resources. Methods A comprehensive study of the geothermal field in the entire Songliao Basin was conducted using oil-test temperatures from 826 wells and thermal conductivities measured by the optical scanning method. Formation temperatures at depths of 1 000 m, 2 000 m, 3 000 m, and 4 000 m were estimated using deep temperature prediction technology. Results The results indicate that the present geothermal gradient in the Songliao Basin ranges from 22.5 to 69.0℃/km, with an average of 44.0℃/km. The thermal conductivity values of rocks in the central depression area are relatively concentrated, mostly ranging from 1.60 W/(m·K) to 2.40 W/(m·K), with an average of 1.84 W/(m·K). Among these, mudstone has the lowest thermal conductivity, with an average of 1.77 W/(m·K); siltstone has a middle range with an average of 1.87 W/(m·K); and fine sandstone has the highest thermal conductivity, with an average of 2.12 W/(m·K). The heat flow ranges from 35.0 to 98.8 mW/m2, with an average of 76.9 mW/m2. The basin exhibits a typical "hot basin" characteristic, with higher heat flow in the central depression and lower heat flow in the slope and uplift areas, forming an annular distribution pattern. Geothermal anomaly areas are distributed in the northeast of the central depression and the northwest of the southeastern uplifted region. The formation temperature at a depth of 1, 000 m ranges from 26.9 to 72.3℃, with an average of 47.9℃; at 2 000 m, it ranges from 49.4 to 141.3℃, with an average of 91.9℃; at 3 000 m, it ranges from 71.8 to 167.5℃, with an average of 135.8℃; and at 4 000 m, it ranges from 94.3 to 210.9℃, with an average of 179.8℃. Conclusion These findings suggest that the subduction of the Pacific Plate beneath the Eurasian Plate has caused upwelling of the asthenosphere and rapid thinning of the regional lithosphere, resulting in a significant increase in heat from the mantle. Simultaneously, the thinned crust facilitates the upward conduction of mantle heat. The widespread NNE and NW fault systems in the basin provide channels for the rise of mantle material and heat flow. Some mantle material remains in the middle and lower crust along deep faults, forming high-conductivity and low-velocity bodies that continuously heat the crust. A portion of the volcanic activity in the Songliao Basin is attributed to the eruption of Cenozoic volcanoes through faults. The presence of granite in the basin's basement plays a significant role in generating heat through the decay of radioactive elements, thereby serving as an important heat source. The heterogeneity of the current geothermal field can be attributed to variations in crustal structure among different tectonic units. The difference in thermal conductivity between the basement and sedimentary layers leads to a "refraction" effect on heat flow, resulting in the redistribution of heat in the shallow part of the basin and the formation of a distinct heat flow distribution pattern between concave and convex areas. The favorable combination of reservoir capacity in the Songliao Basin provides ideal conditions for heat storage, making it conducive for the development of low- and medium-temperature geothermal resources

High-Throughput Metabolomics and Diabetic Kidney Disease Progression: Evidence from the Chronic Renal Insufficiency (CRIC) Study

Introduction: Metabolomics could offer novel prognostic biomarkers and elucidate mechanisms of diabetic kidney disease (DKD) progression. Via metabolomic analysis of urine samples from 995 CRIC participants with diabetes and state-of-the-art statistical modeling, we aimed to identify metabolites prognostic to DKD progression. Methods: Urine samples (N = 995) were assayed for relative metabolite abundance by untargeted flow-injection mass spectrometry, and stringent statistical criteria were used to eliminate noisy compounds, resulting in 698 annotated metabolite ions. Utilizing the 698 metabolites' ion abundance along with clinical data (demographics, blood pressure, HbA1c, eGFR, and albuminuria), we developed univariate and multivariate models for the eGFR slope using penalized (lasso) and random forest models. Final models were tested on time-to-ESKD (end-stage kidney disease) via cross-validated C-statistics. We also conducted pathway enrichment analysis and a targeted analysis of a subset of metabolites. Results: Six eGFR slope models selected 9-30 variables. In the adjusted ESKD model with highest C-statistic, valine (or betaine) and 3-(4-methyl-3-pentenyl)thiophene were associated (p < 0.05) with 44% and 65% higher hazard of ESKD per doubling of metabolite abundance, respectively. Also, 13 (of 15) prognostic amino acids, including valine and betaine, were confirmed in the targeted analysis. Enrichment analysis revealed pathways implicated in kidney and cardiometabolic disease. Conclusions: Using the diverse CRIC sample, a high-throughput untargeted assay, followed by targeted analysis, and rigorous statistical analysis to reduce false discovery, we identified several novel metabolites implicated in DKD progression. If replicated in independent cohorts, our findings could inform risk stratification and treatment strategies for patients with DKD.ISSN:0250-8095ISSN:1421-967

A Translation Inhibitor That Suppresses Dengue Virus In Vitro and In Vivo▿†

We describe a novel translation inhibitor that has anti-dengue virus (DENV) activity in vitro and in vivo. The inhibitor was identified through a high-throughput screening using a DENV infection assay. The compound contains a benzomorphan core structure. Mode-of-action analysis indicated that the compound inhibits protein translation in a viral RNA sequence-independent manner. Analysis of the stereochemistry demonstrated that only one enantiomer of the racemic compound inhibits viral RNA translation. Medicinal chemistry was performed to eliminate a metabolically labile glucuronidation site of the compound to improve its in vivo stability. Pharmacokinetic analysis showed that upon a single subcutaneous dosing of 25 mg/kg of body weight in mice, plasma levels of the compound reached a Cmax (maximum plasma drug concentration) above the protein-binding-adjusted 90% effective concentration (EC90) value of 0.96 μM. In agreement with the in vivo pharmacokinetic results, treatment of DENV-infected mice with 25 mg/kg of compound once per day reduced peak viremia by about 40-fold. However, mice treated with 75 mg/kg of compound per day exhibited adverse effects. Collectively, our results demonstrate that the benzomorphan compounds inhibit DENV through suppression of RNA translation. The therapeutic window of the current compounds needs to be improved for further development