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Studies that investigated the relationship between fasting blood glucose (FBG) and intracerebral hemorrhage (ICH) outcomes were insufficient.We aimed to investigate the association between FBG level and in-hospital clinical outcomes in patients with primary ICH.A total of 34,507 patients were enrolled in the final study. Compared with the reference group, the ≥6.1 and7 mmol/L group showed nonsignificant higher in-hospital mortality (adjusted odds ratio [OR] 1.20, 95% confidence interval [CI] 0.69-2.11, p = 0.52), and a significant higher proportion of intracranial hematoma evacuation (adjusted OR 1.56, 95% CI 1.26-1.92, p 0.001). The ≥7 mmol/L group showed both significant higher in-hospital mortality (adjusted OR 2.08, 95% CI 1.42-3.04, p = 0.52) and a significant higher proportion of intracranial hematoma evacuation (adjusted OR 2.09, 95% CI 1.78-2.47, p 0.001).Higher FBG level was correlated with both higher mortality and proportion of evacuation of intracranial hematoma.

BACKGROUND Nonalcoholic fatty liver disease (NAFLD) is a common metabolic disorder. According to some epidemiological studies and different meta-analysis, it is not clear that whether the relevance of the occurrence and progression of NAFLD and coffee consumption is very close. So we conducted the present article to make it clear. METHODS The PubMed, Cochrane library and Embase were searched up to December 1, 2022. We performed the meta-analysis of not regular coffee vs. regular coffee drinking and coffee drinking vs. the progression of NAFLD, and conducted subgroup analysis of participants, kinds of coffee, methods of diagnosis to verify that relationship. The pooled odds ratio (ORs) and corresponding 95% confidence intervals (CIs) and pooled standardized mean difference (SMD) IV. Random and 95% CIs were calculated by random-effects model. RESULTS Eleven articles were included, including 7093 cases and 20625 non-cases. Whether regular coffee drinking or not was not significantly associated with NAFLD occurrence, and OR were 0.84 (95% CI: 0.43–1.62). Moreover, the pooled SMD IV. Random. from the comparison of coffee drinking vs. the progression of NAFLD was − 0.12(95%CI :-0.31-0.07), showing not statistical significance. What’s more, subgroup analysis of people being obese or not, methods of diagnosis of NAFLD, types of coffee, suggested non beneficial efficacy of coffee drinking on NAFLD. CONCLUSIONS The existing evidence showed coffee drinking did not significantly decrease the occurrence and progression of NAFLD. In addition, different kinds of coffee failed to show any beneficial efficacy on NAFLD. Thus, coffee is not recommended for people to decrease the occurrence and slow the progression of NAFLD. As we were unable to assess the components of coffee on NAFLD, the results of this meta-analysis should be interpreted with caution. Further study is needed to assess the influence of main ingredient of coffee, caffeine, on NAFLD.

The relationship between statins and intracerebral hemorrhage outcomes is unclear.We aimed to compare the in-hospital mortality and evacuation of intracranial hematoma rates in patients with primary intracerebral hemorrhage between prior statin users and nonusers.The final study population included 66,263 patients. Multivariable logistics analyses showed that prior statin use was not associated with in-hospital mortality for primary intracerebral hemorrhage (adjusted odd ratio 0.78, 95% CI 0.61-1.01), but reduced the proportion of patients undergoing evacuation of intracranial hematoma (adjusted odd ratio 0.70, 95% CI 0.61-0.82). Propensity score matching analyses yielded similar results.Prior statin use was not associated with in-hospital mortality but did reduce evacuation of intracranial hematoma rates.

Guangshuo Li,1 Chuanying Wang,1 Shang Wang,1,2 Yahui Hao,2 Yunyun Xiong,1– 3,* Xingquan Zhao1,* 1Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, People’s Republic of China; 2China National Clinical Research Center for Neurological Diseases, Beijing, People’s Republic of China; 3Chinese Institute for Brain Research, Beijing, People’s Republic of China*These authors contributed equally to this workCorrespondence: Xingquan Zhao, Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, No. 119 Nansihuanxilu, Fengtai District, Beijing, 100070, People’s Republic of China, Tel +86– 10– 59975549, Email zxq@vip.163.com Yunyun Xiong, National Clinical Research Center for Neurological Diseases, Beijing, People’s Republic of China, Email xiongyunyun@bjtth.orgObjective: The clinical significance of different glycemic parameters has been rarely investigated in ischemic stroke patients treated with intravenous tissue plasminogen activator (IV tPA). This study was aimed to investigate the association between different glycemic parameters and favorable functional outcome in patients treated with IV tPA.Methods: Patients with ischemic stroke who received IV tPA therapy at our stroke center were retrospectively enrolled. Four glycemic parameters were collected including admission glucose, HbA1c, stress hyperglycemia ratio (SHR) and glycemic gap (GG). Additional information was also recorded including demographics, medical history, stroke severity, imaging measures and mRS score at discharge. We used 5 machine learning models to investigate the predictive value of glycemic parameters.Results: Our study included 294 patients treated with IV tPA. SHR and GG were independently associated with favorable functional outcome (adjusted OR for SHR 0.03, 95% CI 0.01– 0.72, P = 0.03; adjusted OR for GG 1.024, 95% CI 1.00– 1.05, P = 0.04).Conclusion: SHR and GG were associated with functional outcomes in acute ischemic stroke patients with intravenous thrombolysis.Keywords: stroke, thrombolysis, tissue plasminogen activator, glucose, hyperglycemia

Guangshuo Li,1 Yahui Hao,2 Chuanying Wang,1 Shang Wang,1,2 Yunyun Xiong1– 3&ast;, Xingquan Zhao1 &#x002A1Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, People’s Republic of China; 2China National Clinical Research Center for Neurological Diseases, Beijing, People’s Republic of China; 3Chinese Institute of Brain Research, Beijing, People’s Republic of China&ast;These authors contributed equally to this workCorrespondence: Yunyun Xiong, China National Clinical Research Center for Neurological Diseases, Beijing, People’s Republic of China, Email xiongyunyun@bjtth.org Xingquan Zhao, Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, No. 119 Nansihuanxilu, Fengtai District, Beijing, 100070, People’s Republic of China, Email zxq@vip.163.comObjective: Investigations on neutrophil-to-lymphocyte ratio (NLR) and lymphocyte-to-monocyte ratio (LMR) in patients with ischemic stroke are insufficient. We aimed to investigate the relationship of NLR and LMR with in-hospital clinical outcomes at different time points in ischemic stroke patients treated with intravenous tissues plasminogen activator (IV tPA).Methods: We retrospectively enrolled patients who received IV tPA therapy within 4.5 hours from symptoms onset. Demographics, clinical characteristics, imaging measures, and the in-hospital clinical outcomes including early neurological improvement (ENI, defined as NIHSS score reduction within 24 hours ≥ 4 points or decreased to the baseline) and favorable functional outcome (defined as modified Rankin scale 0– 1) were collected. Multivariable logistic regression analyses were performed to test whether NLR or LMR was an independent predictor for the in-hospital clinical outcomes.Results: One hundred and two patients treated with IV tPA were included. NLR at 24 hours proved to be an independent predictor of ENI (adjusted OR=0.85, 95% CI=0.75– 0.95, P=0.04). NLR at 48 hours and LMR at 48 hours proved to be independent predictors of mRS 0– 1 at discharge (NLR at 48 hours: adjusted OR=0.64, 95% CI=0.49– 0.83, P=0.01; LMR at 48 hours: adjusted OR=1.50, 95% CI=1.08– 2.09, P=0.02). The AUC of NLR at 48 hours to predict favorable functional outcome at discharge was 0.79 (95% CI=0.70– 0.88, P< 0.001) and the optimal cut-off was 5.69 (sensitivity=0.52, specificity=0.63).Conclusion: In our study, NLR at 24 hours was correlated with ENI. Both NLR and LMR at 48 hours were closely associated with favorable functional outcomes at discharge.Keywords: stroke, thrombolysis, tissue plasminogen activator, neutrophil, inflammation

Glycemic gap (GG), as a novel biomarker showing the acute glycemic change after the onset of acute illness, has been found to be associated with adverse outcomes in many diseases. This study aimed to explore the prognostic value of GG on long-term outcomes of spontaneous intracerebral hemorrhage (sICH).The current study included 528 patients from a multicenter, prospective, consecutive, observational cohort study. Poor clinical outcome was defined as modified Rankin Scale ≥ 3. GG was calculated using admission blood glucose minus hemoglobin A1c-derived average blood glucose. Logistic regression analyses were performed to determine the association between GG and poor clinical outcomes at 30 days, 90 days, and 1 year.Glycemic gap was significantly associated with poor clinical outcomes at 30 days, 90 days, and 1 year (p lt; 0.05 for all models), where patients with higher GG were more likely to have poor clinical outcome. Restricted cubic splines revealed a positive association between GG and poor clinical outcome. In addition, patients with higher GG were more likely to have a higher 1-year mortality rate. The addition of GG to the intracerebral hemorrhage score improved the discrimination and calibration properties for the prediction of poor clinical outcome.Glycemic gap was independently associated with poor outcomes and may be a valuable prognostic factor in patients with sICH.

At present, the lack of detection technology in underground space area is the main constraint on the development and utilization of underground space. In order to solve the difficult situation of underground space exploration and evaluation, this paper presents a multi-frequency ultrasonic scanning detection technology, a large number of borehole detection data can be obtained by using the detection system to realize the accurate scanning and detection of cavity and the belly rock mass. The stability evaluation standard of cavity is established, which realizes the integration of cavity detection and stability evaluation. This paper provides an important reference for the detection of underground cavity. A scanning point position determination method based on multi-frequency ultrasonic pulse ranging is proposed in this paper, and the coordinates of scanning points are calculated accurately to realize the 3D visualization of cavity contours. Through the refined calculation of space volume, the precise control of space deformation is realized. Then, the characteristic parameters of borehole structural plane are determined after the geometrical feature combination of structural planes and the high-frequency acoustic reflection characteristics, a directional method for rock velocity measurement, is presented for the first time by means of low-frequency acoustic wave transmission. Based on the comparative analysis of echo wave characteristics, the integrity evaluation criteria of cavity are established. Finally, by analyzing the structural characteristics of cavity and upper rock mass, and the parameters which may influence the stability of cavity, combined with an engineering example, a stability evaluation system based on the multi-frequency ultrasonic scanning detecting technology of cavity in the test borehole is formed.

It is of great significance to obtain the high precise structural surface properties of rock mass during the process of deep geotechnical engineering investigation by in-situ instrumentation, especially for preventing disasters and reducing damages. To obtain more detailed features of the structural surface in the image obtained by digital panoramic borehole imaging technique, this paper describes and analyzes the morphological feature of structural surface in the borehole image during in-situ instrumentation, and the feature is used to describe joint roughness coefficient (JRC) and analyzed the anti-sliding ability of borehole rock mass. We use a digital panoramic borehole imaging system to obtain the camera image and related data of borehole rock mass, extract the profile line of structural surface in the image, analyze the dip direction and dip angle, and transform the circular profile line of structural surface into three-dimensional feature. Finally, the statistical parameters of three-dimensional feature from the profile lines in each direction are calculated and used to form a roughness coefficient rose diagram according to related JRC theory. Results show that the rose diagram can well describe the actual three-dimensional morphology of the structural surface and its anisotropy of borehole rock mass structures. This paper provides a novel way to describe the morphological feature of structural surface in borehole image and can be applied to determine the dominant anti-slip direction of rock structure, which can solve the difficulty of obtaining the morphological features and mechanical properties of structural surface in deep rock mass.

Intravenous thrombolysis is the first-line therapy for ischemic stroke, and alteplase has been used as an intravenous thrombolysis drug for over 20 years. However, considering its low rate of recanalization and risk of intracerebral hemorrhage, alteplase may not be the optimal thrombolytic drug of choice for ischemic stroke. Tenecteplase (TNK) is a genetically engineered, mutant, tissue plasminogen activator that is a potential substitute to alteplase in ischemic stroke. The pharmacokinetic advantages of TNK include greater fibrin selectivity than alteplase and prolonged half-life time. In this review, we have summarized the clinical trials of TNK in ischemic stroke.Clinical trials showed a higher recanalization rate of TNK over alteplase without increasing the rate of intracerebral hemorrhage. However, not all clinical trials showed superiority of TNK over alteplase in functional outcomes and early neurological improvement. TNK was superior to alteplase in terms of recanalization in patients who fulfilled the imaging mismatch criteria and in those planning to undergo mechanical thrombectomy.TNK has the potential to substitute alteplase for ischemic stroke therapy. Future TNK clinical trials that target functional outcomes are warranted.

Given the single and one-sided problems of traditional rock mass structure integrity evaluation methods, this paper will use borehole test data that were obtained by conventional logging m...

The relationship between morphological features and mechanical properties of rock structural planes has been an important scientific problem in the field of deep rock mechanics and enginee...

Digital panoramic borehole imaging technology has been widely used in the practice of drilling engineering. Based on many high-definition panoramic borehole images obtained by the borehole imaging system, this paper puts forward an automatic recognition method based on clustering and characteristic functions to perform intelligent analysis and automatic interpretation researches, and successfully applied to the analysis of the borehole images obtained at the Wudongde Hydropower Station in the south-west of China. The results show that the automatic recognition method can fully and quickly automatically identify most of the important structural planes and their position, dip, dip angle and gap width and other characteristic parameter information in the entire borehole image. The recognition rate of the main structural plane is about 90%. The accuracy rate is about 85%, the total time cost is about 3 h, and the accuracy deviation is less than 4% among the 12 boreholes with a depth of about 50 m. The application of automatic recognition technology to the panoramic borehole image can greatly improve work efficiency, reduce the time cost, and avoid the interference caused by humans, making it possible to automatically recognize the structural plane parameters of the full-hole image.

BACKGROUND: Most rhythmic masticatory muscle activities (RMMAs) have been shown to be accompanied with limb movements (LMs) in sleep bruxism (SB) patients during sleep.OBJECTIVES: To compare the relationships between RMMAs and LMs in SB patients and normal subjects.METHODS: Polysomnographic recordings were performed on eight SB patients and nine normal subjects and the frequencies and durations of RMMAs as well as LMs were determined. Linear regression and correlation analysis was performed to study the relationship between durations of RMMAs and LMs when RMMAs occurred with LMs.RESULTS: Most LMs in SB patients, but not in normal subjects, were accompanied with RMMAs. RMMAs in SB patients were more likely to be isolated, phasic or mixed, while RMMAs in normal subjects were more likely to be tonic. The frequencies of LMs, isolated RMMAs and RMMAs accompanied with LMs in SB patients were significantly higher than those in normal subjects. Furthermore, linear regression and correlation analysis showed that duration of RMMAs was significantly associated with that of LMs when RMMAs occurred with LMs. The duration of RMMAs, when accompanied with LMs, in SB patients was significantly longer than that in normal subjects.CONCLUSIONS: Close relationships between LMs and RMMAs exist in SB patients and normal subjects, and SB episodes may be part of cortical arousal responses and the increased cortical activities associated with SB episodes may not just be localized to the central nervous system (CNS) that controls jaw movements but may also include other parts of CNS that controls LMs. This article is protected by copyright. All rights reserved.

Quantifying diametric deformations of boreholes is vital in rock engineering due to its applications in the determination of in-situ stresses using the stress relief methods. New methods are desired to overcome the harsh environment featuring high temperature and high pressure in deep boreholes. Therefore, this study develops an apparatus using rigid probes combined with microscopic camera to measure borehole diametric deformation. The structural design of the rigid probe and package of the measuring device avoid the advert impact of environmental factors. The usage of multi-probes and high resolution micro-optical imaging technique enables simultaneous collection of multi borehole diametric deformation data. Furthermore, using these data, a new method of borehole shape measurement is proposed at high speed compared with traditional methods that measure one diametric deformation at a time. The feasibility of the system is verified by conducting laboratory tests. This system can be readily used in the in-situ stress measurement based on borehole shape analysis.

A hidden karst cave has a prominent influence on the design and construction of underground engineering. In order to improve the automatic identification accuracy of hidden karst cave area...

The stress relief method is currently one of the most commonly used in situ stress measurement methods, and its basic measurement principle is the relationship between borehole deformation...

Moving particles and the topographic bed under muddy water or in sediment-laden flow are often clouded by suspended sediments, making it hard to detect or analyze for visualization. This paper concerns applications of ultrasound imaging measurement method for the visual measurement of related water-sand parameters during sediment transport process in hydraulic model experiments. We use a B-mode ultrasound imaging system to measure the related parameters of suspended sediment concentration (SSC), underwater topographic riverbed, flow velocity and sediment incipient motion, conducted at a water channel. A comprehensive measuring system for the visualization of multiple water-sand parameters is established. Results show that the measurement and analysis of SSC and its space distribution, topography bedform, flow velocity and flow field, and sediment incipient velocity can be realized. Ultrasound imaging measurements of SSC and their space distribution can be shown in real time, and also dynamic monitoring and analysis of sediment incipient motion and topography bedform during the sediment transport process. This method realizes the experimental visualization of the topographic bed and sediment-laden flow. Application of an ultrasound imaging measurement system has promoted the development of sediment movement law research and related hydraulic model experiment measurement technique.

Digital panoramic borehole camera technology has been widely employed in actual projects, and a large number of high-accuracy borehole camera images have been obtained. Borehole camera images accurately record the geological information, especially the feature parameters of structure plane. However, since the acquisition of these features is usually done by hand, the workload is large and the results can be affected by human error. To solve this problem, this paper presents an automatic interpretation method of structure plane parameters in borehole camera image. In this method, image pixel gray, gradient values and projection method are employed to distinguish the occurrence region of structural planes. Then, standard sine function matching method is employed to search the structure plane in the region. Lastly, the optimal sine curve is screened out and adopted as the feature curve of structure plane. Related parameters of sine curve are analyzed and converted into the parameters of structure plane, such as the central position, orientation, dip angle and fracture width of structural planes. This method can automatically identify structure planes in the image continuously and quickly, and obtain the corresponding structural parameters. The method is stable and reliable, and greatly improves the working efficiency. It can perform the automatic interpretation of structure planes and extraction of geometric parameters, and provide an effective and consistent solution for drilling information acquisition and borehole camera image signal processing.

In this study, we used digital borehole image camera to obtain images of porosity distribution in coral reefs in South China Sea, and developed an effective evaluation system for such distributions. First, the original images are preprocessed, allowing the pore regions to be automatically detected. The depth and sectional functions are established to measure five parameters: pore count, pore radius, radius concentration rate, total pore area ratio, and fractal dimension count. These are used to calculate the characteristic values of porosity distributions, and their fuzzy relationships are used to build the evaluation model, determine the Hamming distances between distributions, and establish the relationships between the characteristics and coral rock classifications. Test results from applying the method on a deep borehole image segment show the results to be consistent with other methods, and the following conclusions can be reached: (1) the porosity evaluation model is a viable way to analyze ...

Sediment incipient velocity (SIV) is an important parameter for the rule of sediment movement and fluvial processes in the river sediment engineering. The field measurement of the SIV during the process of sediment incipient motion near the riverbed is a difficult problem. For this problem, this paper puts forward a novel method of measuring SIV by using B-scan ultrasound imaging device and current meter in the water channel of river model experiment. In this method, we use a B-scan ultrasound imaging device to get the ultrasonic images of moving particles and riverbed under the water, and use a current meter to obtain the flow velocities of observed points near the bed at the same time. By statistical analysis of the images, relationships between the imaging spot number/area of particles and the water flow velocity are obtained, which have shown the whole process of sediment incipient motion clearly. Results show there are some suddenly changed positions in these relationships. These suddenly changed positions correspond to the states of incipient motion, which can be used to analyse and measure the SIV. After kinds of model experiments, the measured SIV is within an acceptable range and can be verified by the change of riverbed boundary lines. This method is very suitable for river model experiments, especially for water channel test under muddy water or sediment-laden flow. This paper provides a new approach to the research and analysis of sediment movement with the advantages of direct observation and real-time research.

As a breakthrough in borehole imaging technology, digital panoramic borehole camera technology has been widely employed. The high-resolution panoramic borehole images can accurately reproduce the geometric features of structural planes. However, the detection of these features is usually done manually, which is both time-consuming and introduces human errors. To solve this problem, this paper presents a method for the automatic recognition and parameter extraction of borehole geometric features of camera images. In this method, the image's gray and gradient level, and also their projection on the depth axis are used to identify the locations of structural planes. Afterwards, iterative matching is employed by using a template of sinusoidal function to search for structural planes in the identified image blocks. Finally, optimal sine curves are selected as the feature curves of structural planes, and their related parameters are converted into structural plane parameters required for engineering, such as their positions, dip directions, dip angles and fracture widths. The method can automatically identify all of structural planes throughout the whole borehole camera image in a continuous and rapid manner, and obtain the corresponding structural parameters. It has proven highly reliable, accurate and efficient.

Hypoxia is a major cause of treatment resistance in breast cancer. Single-walled carbon nanotubes (SWCNTs) exhibit unique properties that make them promising candidates for breast cancer treatment. In the present study, a new functionalized single-walled carbon nanotube carrying oxygen was synthesized; it was determined whether this material could increase chemosensitivity and radiosensitivity of human breast cancer cell lines, and the underlying mechanisms were investigated. MDA-MB-231 cells growing in folic acid (FA) free medium, MDA-MB-231 cells growing in medium containing FA and ZR-75-1 cells were treated with chemotherapy drugs or radiotherapy with or without tombarthite-modified-FA-chitosan (R-O2-FA-CHI)-SWCNTs under hypoxic conditions, and the cell viability was determined by water-soluble tetrazolium salts-1 assay. The cell surviving fractions were determined by colony forming assay. Cell apoptosis induction was monitored by flow cytometry. Expression of B-cell lymphoma 2 (Bcl-2), survivin, hypoxia-inducible factor 1-α (HIF-1α), multidrug resistance-associated protein 1 (MRP-1), P-glycoprotein (P-gp), RAD51 and Ku80 was monitored by western blotting. The novel synthesized R-O2-FA-CHI-SWCNTs were able to significantly enhance the chemosensitivity and radiosensitivity of human breast cancer cell lines and the material exhibited its expected function by downregulating the expression of Bcl-2, survivin, HIF-1α, P-gp, MRP-1, RAD51 and Ku80.

Ultrasound imaging technique is applied to river model test in recent years, but the imaging features and inner relationships of sediments are still waiting for further study. This paper proposes some new relationships between B-mode ultrasound imaging signals and suspended sediment concentrations (SSC) after kinds of model experiments are conducted in a glass flume. And the influences of particle size, sediment material, ultrasonic frequency and flow velocity on the relationships are discussed in practical applications. Results show that the imaging area concentration (IAC), gray area concentration (GAC) and gray energy density (GED) of sediment imaging signals increase with the addition of sediments until images are filled with imaging signals. The GAC is the best one because of the widest variation range and better sensitivity when compared with the IAC. The GED is the most sensitive to the change of SSC, but it is easiest to reach saturation. The relationship between the GAC and actual SSC can be used to estimate unknown SSC and its vertical distribution when the concentration is below 4.0‰ with advantages of direct observation and real time.

In this work, β-NaYF 4 :Yb,Er upconversion (UC) film was successfully prepared on silicon (Si) substrate via self-assemble method for the first time. The chemical composition and surface morphology of the UC film were characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), water contact angle (WCA), X-ray power diffraction (XRD), and scanning electron microscopy (SEM) measurements. To investigate the effects of KH-560 primer film and chemical reactions on the UC luminescence properties of β-NaYF 4 :Yb,Er UC film, decay profiles of the 540 nm and 655 nm radiations were measured. Furthermore, tribological test was applied to qualitatively evaluate the adhesion of the UC film. The results indicate that the UC film has been successfully prepared on Si substrate by covalent chemical bonds. This work provides a facile way to synthesize β-NaYF 4 :Yb,Er UC film with robust adhesion to the substrate, which can be applicable for other UC films.

Yb3+ and Er3+ ions co-doped α-NaYF4:Yb3+, Er3+ nanocrystals were successfully synthesized via a facile hydrothermal method using citric acid (CA) as chelating ligand and NaNO3 as mineralizer. The influences of the CA/RE (RE = Y+Yb+ Er) molar ratio, reaction time, reaction temperature and the NaNO3/RE molar ratio on the crystal phases and shapes of as-prepared products have been well investigated. The possible formation mechanism has been discussed in detail and an aggregation growth theory has been proposed. X-ray diffraction (XRD), transmission electron microscopy (TEM), selected area electron diffraction (SAED), scanning electron microscopy (SEM), and photoluminescence (PL) spectra were used to characterize the products. Under 980 nm excitation, the emission intensities of the as-prepared nanocrystals were much stronger than that of the nanocrystals modified by ethylenediaminetetraacetic acid (EDTA). Additionally, the as-prepared products maintained spherical shape and high degree of monodispersion, which is expected to be suggestive for the preparation of other complex rare earth fluoride compounds.

Fractures from borehole wall images are different from those from surface outcrop in trace pattern, distribution pattern, parameters description and so on. Focus on the geometric parameters of fractures from borehole images, a method for mathematical quantitative description of these fractures is proposed. The fracture from borehole images is described into a point in spatial coordinate system, and this point is defined Fracture Feature Point. The key parameters including dip direction, dip angle and position depth of fractures from borehole wall images are converted into coordinates of fractures feature points. The related calculation equations are deduced in local coordinate system and spatial coordinate system. Furtherly, the space distribution regularities of the fractures based on the distribution characteristics of fracture feature points are summarized. Typical application in multiple boreholes of this description method is studied and an analysis method for any two fractures’ connectivity is established based on Fracture Feature Point. The results of an engineering example research show that the method is effective in fractures connectivity analysis. The mathematical quantitative description method of fractures from borehole wall images will provide new ideas of the research on deep rock mass structure.