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Hot dry rock (HDR) is a kind of clean energy with significant potential. Since the 1970s, the United States, Japan, France, Australia, and other countries have attempted to conduct several HDR development research projects to extract thermal energy by breaking through key technologies. However, up to now, the development of HDR is still in the research, development, and demonstration stage. An HDR exploration borehole (with 236 °C at a depth of 3705 m) was drilled into Triassic granite in the Gonghe Basin in northwest China in 2017. Subsequently, China Geological Survey (CGS) launched the HDR resources exploration and production demonstration project in 2019. After three years of efforts, a sequence of significant technological breakthroughs have been made, including the genetic model of deep heat sources, directional drilling and well completion in high-temperature hard rock, large-scale reservoir stimulation, reservoir characterization, and productivity evaluation, reservoir connectivity and flow circulation, efficient thermoelectric conversion, monitoring, and geological risk assessment, etc. Then the whole-process technological system for HDR exploration and production has been preliminarily established accordingly. The first power generation test was completed in November 2021. The results of this project will provide scientific support for HDR development and utilization in the future.©2022 China Geology Editorial Office.

Displacement is a critical indicator that reflects the degeneration of overall stiffness for bridges. However, for most bridges, contact displacement measurement is difficult to achieve due to the lack of reference points and technical limitations. In this paper, a unique dual-camera visual sensor system for the whole field displacement measurement of bridge undersurfaces was developed. The visual sensor system relies on feature point algorithm and several algorithms are involved to improve the accuracy and efficiency. The dual-camera equipment can independently eliminate the impact of the camera vibration, thereby solving the problem of camera vibration caused by ground vibrations and wind loads at outdoor inspection sites when measuring bridge displacement. In a laboratory testing environment, a steel plate simulated a bridge and different experiments were conducted to test the visual system in situations with and without vibration disturbances to the camera. The results verify the accuracy of the developed visual sensor, especially the effectiveness of the vibration reduction method. [ABSTRACT FROM AUTHOR]

Background/purpose: The therapeutic efficacy of percutaneous transluminal angioplasty and stenting (PTAS) of post-irradiated stenosis of subclavian artery (PISSA) was not well clarified. This retrospective study was designed to evaluate the technical safety and outcome of the patients of severe symptomatic PISSA accepted PTAS. Methods: Between 2000 and 2019, 16 cases with 17 lesions of symptomatic and medically refractory PISSA accepted PTAS were included. We evaluated their technical success, peri-procedural complications and diffusion-weight imaging (DWI) of brain magnetic resonance imaging (MRI), results of symptom relief, and long-term stent patency. Results: The stenosis of the 17 stenotic lesions were 81.2 ± 11.1%. The most common symptom of the 16 patients was dizziness (14/16, 87.5%). All successfully accepted PTAS without neurological complication and had symptom relief after PTAS (17/17, 100%). Of the 12 patients accepted pre-procedural and early post-procedural MRI follow-up, 2 patients had an asymptomatic tiny acute embolic infarct in the territory of vertebrobasilar system. In a 51.9 ± 54.9 months follow-up, all patients had no severe restenosis and no recurrent vertebrobasilar ischemic symptoms. Conclusion: For patients with PISSA and medically refractory ischemic symptoms, PTAS can be an effective alternative management.

Aims: Plant S concentration (Sc) and nitrogen (N) to S ratio (N:S) in canola are important indicators for diagnosing S deficiency. A field study was conducted on sandy and clay loam soils at two sites in eastern Canada for three growing seasons to determine plant critical Sc and N:S ratios across various growth stages (GSs). Methods: For each site year, factorial experiments consisting of combinations of four N levels (0, 80, 160, and 240 kg N ha–1) as urea (46–0–0) and four S levels (0, 20, 30, and 40 kg S ha–1) as potassium sulfate (0–0–50–18) were classified orthogonally to form 16 combinations. Muriate of potash (0–0–60) was also applied as needed to ensure all plots receiving the equal amount of potassium (K). Results: Our study found that S fertilization increased plant Sc at each GS but reduced the whole‐plant N:S ratio, and the effect was stronger during the flowering stage. Both whole‐plant Sc and N:S ratios varied with GS, environment, and soil type and declined with plant aging. Our results showed that whole‐plant S analysis combined with visual signs of plant S deficiency (purple‐edged and cup‐shaped leaves with less green; stunted growth, slow blooming, and fewer flowers) appeared to be the best way to identify S problems in the field, and whole‐plant Sc and N:S ratios could confirm S deficiencies. Conclusion: Our findings indicated that if the whole‐plant Sc in the rosette stage is <0.35% and the N:S ratio is >9.6, the plant may be S‐deficient, and timely supplementary S fertilization measures may be beneficial to canola crop yield. [ABSTRACT FROM AUTHOR]

Abstract Severe extracranial carotid stenosis (SECS) patients may present with nonspecific neurological symptoms that require intracranial magnetic resonance imaging (MRI) and time-of-flight (TOF)-MR angiography (MRA) to exclude intracranial pathology. Recognition of SECS on intracranial TOF-MRA findings is beneficial to provide a prompt carotid imaging study and aggressive stroke prevention. Patients with SECS (January 2016 to May 2019) undergoing percutaneous transluminal angioplasty and stenting (PTAS) were included. Differences in normalized signal intensities (SRICA) and diameters (DICA) between bilateral petrous internal carotid arteries (ICAs) were calculated 1 cm from the orifice. A hypothesized criterion describing the opacification grades (GOPH) of bilateral ophthalmic arteries was proposed. We correlated SRICA (p = 0.041), DICA (p = 0.001) and GOPH (p = 0.012), with the severity of extracranial carotid stenosis on digital subtractive angiography (DSA) in the examined group (n = 113), and all showed statistical significance in predicting percentages of ICA stenosis. The results were further validated in another patient group with SECS after radiation therapy (n = 20; p = 0.704 between the actual and predicted stenosis grades). Our findings support the evaluation of the signal ratio and diameter of intracranial ICA on TOF-MRA to achieve early diagnosis and provide appropriate management of SECS.

Quantifying the relationships of maize yield and nitrogen use efficiency (NUE) to inherent soil productivity (ISP) could provide a theoretical basis for implementing strategies that concurrently narrow the yield gap, increase NUE, and improve soil quality. A field study under irrigation conditions was conducted at five locations with large differences in ISP (estimated by maize grain yield without using fertilizers) across various ecological regions in Inner Mongolia, China. Our results showed that the changes in maize yield and nitrogen partial factor productivity (PFPN) to ISP followed a linear-plateau model, with a common inflection point. When ISP was below 8.0 t ha–1, maize yield and PFPN were stagnating at a low level, due to a trade-off between the contribution of soil and chemical fertilizers to yield. When ISP exceeded 8.0 t ha–1, the contribution rate of soil to yield stabilized at 80%, resulting in a simultaneous increase in maize yield by 1.2 t ha–1 and PFPN by 4.6 kg kg–1, for increasing ISP at each t ha–1. Our results indicated that while keeping other management strategies unchanged, to increase maize yield and PFPN by 15% or further 30%, it is necessary to increase ISP to 9.3 and 10.4 t ha–1, respectively. In this scenario, N input will be reduced by 33.5 and 47.5%, and apparent N losses will be reduced by 11.7 and 21.5%, respectively. Therefore, enhancing ISP could lead to a simultaneous improvement in yield and NUE as well as strongly support the green development of maize production.

Nitrogen (N) is an essential nutrient for plant healthy growth and development, determining crop performance and yield outcomes. However, less than 50% of the N fertilizer applied in modern agricultural systems is effectively utilized by crops in the year of planting, causing resource waste and environmental harm. To improve N use efficiency (NUE), it is crucial to prioritize root performance as it primarily controls the plants' ability to absorb and utilize soil nutrients. The robustness of the root system is also closely related to crop lodging, which is an important factor that hinders the absorption, assimilation, translocation and distribution of N in major field crops. This review attempts to comprehensively summarize recent advances in plant root biology in the context of climate change, emphasizing its important role in soil nutrient dynamics and crop lodging risk, as well as its comprehensive impact on NUE of field grain crops. We discussed the importance of balanced and precision nutrient management to improve NUE and highlighted the innovative role of machine learning in modern agriculture, including root phenotyping, crop lodging detection and nutrient management decisions. Overall, combining machine learning with root biology, along with other practices such as crop rotation, cover cropping, use of biostimulants, and balanced nutrient supply, can reduce lodging risk and promote N uptake and utilization, thereby simultaneously improving NUE, crop productivity and agroecosystem sustainability. This helps ultimately secure our food supply while minimizing the negative impact of N on the environment facing unprecedent climate change. [ABSTRACT FROM AUTHOR]

BackgroundClinical-diffusion mismatch between stroke severity and diffusion-weighted imaging lesion volume seems to identify stroke patients with penumbra. However, urgent magnetic resonance imaging is sometimes inaccessible or contraindicated. Thus, we hypothesized that using brain computed tomography (CT) to determine a baseline "clinical-CT mismatch" may also predict the responses to thrombolytic therapy.MethodsBrain CT lesions were measured using the Alberta Stroke Program Early CT Score (ASPECTS). A total of 104 patients were included: 79 patients with a baseline National Institutes of Health Stroke Scale (NIHSS) score ≥ 8 and a CT-ASPECTS ≥ 9 who were defined as clinical-CT mismatch-positive (P group) and 25 patients with an NIHSS score ≥ 8 and a CT-ASPECTS < 9 who were defined as clinical-CT mismatch-negative (the N group). We compared their clinical outcomes, including early neurological improvement (ENI), early neurological deterioration (END), delta NIHSS score (admission NIHSS-baseline NIHSS score), symptomatic intracranial hemorrhage (sICH), mortality, and favorable outcome at 3 months.ResultsPatients in the P group had a greater proportion of favorable outcome at 3 months (p = 0.032) and more frequent ENI (p = 0.038) and a greater delta NIHSS score (p = 0.001), as well as a lower proportion of END (p = 0.004) than those in the N group patients. There were no significant differences in the incidence rates of sICH and mortality between the two groups.ConclusionsClinical-CT mismatch may be able to predict which patients would benefit from intravenous thrombolysis.

Background and purpose: The goal of this study was to assess the potential risk factors leading to flow-related aneurysm (FA) formation in patients with brain arteriovenous malformations (BAVMs) in Taiwanese. Methods: We recruited 890 patients with BAVMs: 72 had FA(s) and 818 did not. Several factors were assessed including patient's age, gender, BAVM volume and location, and Spetzler-Martin grade. Results: The 890 patients with BAVM had a mean age of 30 years (range: 2–84), mean BAVM volume of 10.6 mL (range: 0.13–91.4). BAVMs were ruptured in 42% of patients. Compared to BAVM patients without FAs, the 72 patients with FAs had older age (mean 41 yrs vs 31 yrs, p

Background/Aims: Osteoporosis is a commonly occurring condition marked by a loss of bone density. Previous evidence has highlighted the roles played by microRNAs as potential treatment tools for the disease. At present, the influence of long non-coding RNAs (lncRNAs) on the progression of osteoporosis remains largely unclear. Thus, an investigation was conducted into the target relationship between LINC00311, which has been reported to be highly expressed in osteoporosis, and delta-like 3 (DLL3), which is involved in the Notch signaling pathway, in connection with a series of bioinformatic methods. An osteoporotic rat model was established by means of ovariectomy (OVX) to evaluate the influence exerted by DLL3-binding LINC00311 on osteoclasts through the Notch signaling pathway. Methods: Osteoclasts were extracted from osteoporotic rats and transfected with the LINC00311-vector, shRNA-LINC00311, Notch activator, or a combination of the Notch activator and LINC00311-vector. Western blotting and RT-qPCR techniques were applied to determine the expression levels of LINC00311, DLL3, Notch1, Notch2, Jagged1, Hes-1 and TRAP in tissues and cells, while cell activity was detected by MTT assay. The cell cycle as well as the rate of apoptosis was detected by flow cytometry. The successfully established osteoporotic rats were designated into the OVX-siRNA, OVX-LINC00311 and OVX-control groups to observe the effects of LINC00311 on the proliferation and differentiation of osteoclasts. Results: Cells transfected with the LINC00311-vector exhibited increased expression levels of Notch2 and TRPA as well as increased cell activity, while decreased expression levels of DLL3, Notch1, Jagged1 and Hes-1, along with a decreased cell apoptosis rate, were observed. The opposite tendencies of these parameters were observed in the cells treated with shRNA-LINC00311. A key observation was made when the Notch signaling pathway was activated, in that the cell activity was decreased while the rate of apoptosis increased. In comparison with the OVX-control group, the expression levels of LINC00311, Notch2 and TRAP as well as the positive expression rate of TRAP all exhibited reductions, while those of DLL3, Jagged1 and Notch1 were elevated in the OVX-siRNA group. Compared with those in the sham group, in the OVX-control and OVX-LINC00311 groups, LINC00311 and the expression levels of Notch2 and TRAP were increased; however, decreased levels of DLL3, Jagged1 and Notch1 were noted. Conclusions: Taken together, the key findings of the present study suggest that LINC00311 induces proliferation and inhibits apoptosis of osteoclasts via the regulation of the Notch signaling pathway by inhibiting DLL3 expression, ultimately demonstrating that LINC00311 and its target gene DLL3 may serve as independent factors in cases of osteoporosis.