Biomass is important in monitoring global carbon storage and the carbon cycle, which quickly and accurately estimates forest biomass. Precision forestry and forest modeling place high requirements on ...obtaining the individual parameters of various tree species in complex stands, and studies have included both the overall stand and individual trees. Most of the existing literature focuses on calculating the individual tree species’ biomass in a single stand, and there is little research on calculating the individual tree biomass in complex stands. This paper calculates the individual tree biomass of various tree species in complex stands by combining multispectral and light detection and ranging (LIDAR) data. The main research steps are as follows. First, tree species are classified through multispectral data combined with field investigations. Second, multispectral classification data are combined with LIDAR point cloud data to classify point cloud tree species. Finally, the divided point cloud tree species are used to compare the diameter at breast height (DBH) and height of each tree species to calculate the individual tree biomass and classify the overall stand and individual measurements. The results show that under suitable conditions, it is feasible to identify tree species through multispectral classification and calculate the individual tree biomass of each species in conjunction with point-cloud data. The overall accuracy of identifying tree species in multispectral classification is 52%. Comparing the DBH of the classified tree species after terrestrial laser scanning (TLS) and unmanned aerial vehicle laser scanning (UAV-LS) to give UAV-LS+TLS, the concordance correlation coefficient (CCC) is 0.87 and the root-mean-square error (RMSE) is 10.45. The CCC and RMSE are 0.92 and 1.41 compared with the tree height after UAV-LS and UAV-LS+TLS.
Direct mechanical thrombectomy (DMT) was confirmed non-inferior to bridge mechanical thrombectomy (BMT, MT preceded by intravenous alteplase within 4.5 h after symptom onset) for acute ischemic ...stroke with large vessel occlusions (AIS-LVO) in mothership patients. However, the noninferiority of DMT in the general population (including drip and ship mode) is controversial, and the impact of thrombolysis on retrieval attempts remains uncertain. This was a post-hoc analysis of a multi-center, prospective enrolled study. Patients were divided into the BMT group and the DMT group. Baseline characteristics and clinical outcomes were compared by using univariate analysis, multivariable analysis, and propensity score matching analysis, respectively. Of all 245 patients enrolled in this study, 79 (32.2%) patients underwent BMT. In the multivariable analysis, the ratio of excellent prognosis (defined as modified Rankin Scale mRS score 0–1 at 90 days) was significantly higher in the BMT group compared with the DMT group (odds ratio, 2.731; 95% confidence interval, 1.238–6.023;
P
= 0.013). The ratio of good prognosis (mRS score 0–2 at 90 days), successful recanalization rate modified Thrombolysis In Cerebral Ischemia (mTICI) score 2b-3 and mortality rate were similar between the two groups. The excellent prognosis rate was significantly higher in the BMT group after propensity score matching (
P
= 0.023). BMT was associated with a higher ratio of excellent prognosis (mRS 0–1) and a similar successful recanalization rate without increasing peri-operation complications compared with DMT in AIS-LVO patients. It is prudent to continue BMT until further data is available.
Graphic abstract
Many small birds living in regions with seasonal fluctuations and ambient temperatures typically respond to cold by increasing metabolic thermogenesis, internal organ mass and the oxidative capacity ...of certain tissues. In this study, we investigated seasonal adjustments in body mass, resting metabolic rate (RMR), evaporative water loss (EWL), the mass of selected internal organs, and two indicators of cellular aerobic respiration (mitochondrial state-4 respiration and cytochrome c oxidase activity) in Chinese hwamei (Garrulax canorus) that had been captured in summer or winter from Wenzhou, China. RMR and EWL were higher in winter than in summer. State-4 respiration in the heart, liver, kidneys and pectoral muscle, as well as cytochrome c oxidase activity in the liver, kidneys and pectoral muscle were also higher in winter than summer. In addition, there was a positive correlation between RMR and EWL, and between RMR and indicators of cellular metabolic activity in the heart, liver, kidneys and pectoral muscle. This phenotypic flexibility in physiological and biochemical thermoregulatory responses may be important to the hwamei's ability to survive the unpredictable, periodic, cold temperatures commonly experienced in Wenzhou in winter.
Breast cancer (BC) is the malignancy with the highest mortality rate among women, identification of immune-related biomarkers facilitates precise diagnosis and improvement of the survival rate in ...early-stage BC patients. 38 hub genes significantly positively correlated with tumor grade were identified based on weighted gene coexpression network analysis (WGCNA) by integrating the clinical traits and transcriptome analysis. Six candidate genes were screened from 38 hub genes basing on least absolute shrinkage and selection operator (LASSO)-Cox and random forest. Four upregulated genes (
CDC20
,
CDCA5
,
TTK
and
UBE2C
) were identified as biomarkers with the log-rank
p
< 0.05, in which high expression levels of them showed a poor overall survival (OS) and recurrence-free survival (RFS). A risk model was finally constructed using LASSO-Cox regression coefficients and it possessed superior capability to identify high risk patients and predict OS (
p
< 0.0001, AUC at 1-, 3- and 5-years are 0.81, 0.73 and 0.79, respectively). Decision curve analysis demonstrated risk score was the best prognostic predictor, and low risk represented a longer survival time and lower tumor grade. Importantly, multiple immune cell types and immunotherapy targets were observed increase in expression levels in high-risk group, most of which were significantly correlated with four genes. In summary, the immune-related biomarkers could accurately predict the prognosis and character the immune responses in BC patients. In addition, the risk model is conducive to the tiered diagnosis and treatment of BC patients.
Determining the occlusion mechanism before endovascular treatment (EVT) is of great significance for acute large vessel occlusion patients. We aimed to develop and validate a simple pre-EVT scale ...with readily available variables for predicting
atherosclerotic thrombosis (ISAT) in acute vertebrobasilar artery occlusion (VBAO) patients.
Consecutive patients were retrieved from Nanjing Stroke Registry Program between January 2014 and December 2019 as a derivation cohort. Anonymous data of consecutive patients between January 2014 and December 2019 were collected from another comprehensive stroke center as an external validation cohort. Demographics, medical histories, and clinical characteristics were collected. ISAT was defined according to the following criteria: (a) detection of moderate to severe (≥50%) stenosis or stenosis with significant distal flow impairment at the occluded segment when successful reperfusion was achieved; (b) transient visualization of eccentric plaque contour or a recurrent re-occlusion tendency when reperfusion was unsuccessful. Logistic regression was taken to develop a predictive scale. The performance of the scale was assessed by area under the receiver operating characteristic curve (AUC) and Hosmer-Lemeshow test.
ISAT was observed in 41 of 95 (43.2%) patients included in the derivation cohort. The ISAT predictive scale consisted of three pre-interventional predictors, including the history of hypertension, atrial fibrillation rhythm, and baseline serum glucose level ≥7.55 mmol/L. The model depicted acceptable calibration (Hosmer-Lemeshow test,
= 0.554) and good discrimination (AUC, 0.853; 95% confidence interval, 0.775-0.930). The optimal cutoff value of the ISAT scale was 1 point with 95.1% sensitivity, 64.8% specificity, and 77.9% accuracy. In the validation cohort, the discrimination ability was still promising with an AUC value of 0.800 (0.682-0.918).
The three-item scale comprised of the history of hypertension, atrial fibrillation rhythm, and dichotomous serum glucose level had a promising predictive value for ISAT before EVT in acute VBAO patients.
Micro-scale cracks on the surface of a magnetic rotor are difficult to detect because of the formation of stains. A method that is based on computer vision and a support vector machine (SVM) that can ...accurately and rapidly locate micro-scale cracks are proposed. To further highlight the cracks and reduce interference, the image is pre-processed using improved adaptive median filtering, image sharpening, extract feature point, and an expansion based on mathematical morphology. Next, the feature curves of cracks and stains are extracted as training samples using the feature curve extract algorithm and the region orientation algorithm (ROA) for continuous and discontinuous crack curves images, respectively. SVM is later used to distinguish between the two types of image sources. An improved region orientation algorithm (IROA) is proposed to increase the efficiency of discontinuous crack curves images through online detection. Experiment results show that the accuracy of crack detection using ROA is 97.9%, and the accuracy is 94.7% using IROA. However, the IROA algorithm execution time is 3% that of ROA, and IROA's average crack detection time is shorter than that of ROA by 51%. The proposed method provides the basis for the automatic online detection of micro-scale cracks on a magnetic rotor surface and paves the way for the identification of cracks on complex morphologies, such as split cracks and circular cracks.
In the situation of mass vaccination against COVID-19, few studies have reported on the early kinetics of specific antibodies (IgG/IgM/IgA) of vaccine breakthrough cases. There is still a lack of ...epidemiological evidence about the value of serological indicators in the auxiliary diagnosis of COVID-19 infection, especially when the nucleic acid results were undetectable. Omicron breakthrough cases post-inactivated vaccination (
= 456) and COVID-19-naive individuals with two doses of inactivated vaccination (
= 693) were enrolled. Blood samples were collected and tested for SARS-CoV-2 antibody levels based on the magnetic chemiluminescence enzyme immunoassay. Among Omicron breakthrough cases, the serum IgG antibody level was 36.34 Sample/CutOff (S/CO) (95% confidence interval CI, 31.89 to 40.79) in the acute phase and 88.45 S/CO (95% CI, 82.79 to 94.12) in the recovery phase. Serum IgA can be detected in the first week post-symptom onset (PSO) and showed an almost linear increase within 5 weeks PSO. Compared with those of breakthrough cases, IgG and IgA titers of the postimmune group were much lower (4.70 S/CO and 0.46 S/CO, respectively). Multivariate regression showed that serum IgG and IgA levels in Omicron breakthrough cases were mainly affected by the weeks PSO (
< 0.001). Receiver operating characteristic ROC0 curve analysis showed that the area under the curve (AUC) was 0.744 and 0.806 when the cutoff values of IgA and IgG were 1 S/CO and 15 S/CO, respectively. Omicron breakthrough infection can lead to a further increase in IgG and IgA levels relative to those of the immunized population. When nucleic acid real-time PCR was negative, we would use the kinetics of IgG and IgA levels to distinguish the breakthrough cases from the immunized population.
This study fills a gap in the epidemiological evidence by investigating the value of serological indicators, particularly IgG and IgA levels, in the auxiliary diagnosis of COVID-19 infections when nucleic acid results are undetectable. The findings reveal that among Omicron breakthrough cases, both IgG and IgA antibody levels exhibit significant changes. Serum IgG levels increase during the acute phase and rise further in the recovery phase. Serum IgA can be detected as early as the first week post-symptom onset (PSO), showing a consistent linear increase within 5 weeks PSO. Furthermore, receiver operating characteristic (ROC) curve analysis demonstrates the potential of IgG and IgA cutoff values as diagnostic markers. The study's conclusion underscores the importance of monitoring IgG and IgA kinetics in distinguishing Omicron breakthrough cases from vaccinated individuals. These findings contribute to the development of more accurate diagnostic approaches and help inform public health strategies during the ongoing COVID-19 pandemic.
A high groundwater level is highly relevant to the slope instability. Drainage tunnel is an effective method for groundwater level control, but its effect on landslide hydrogeological characteristics ...is rarely discussed. This study analysed the changes of the landslide hydrogeological characteristics under the effect of a drainage tunnel by real‐time monitoring of rainfall, groundwater level, and surface displacement. The trend and mutation of groundwater level are analysed by the Mann–Kendall test and the Mann–Kendall mutation test. The memory effect of groundwater in the landslide area was analysed using autocorrelation analysis. The response characteristics of groundwater level to rainfall were evaluated using cross‐correlation analysis and mutual information theory. Variations of groundwater levels were further investigated based on hydrograph analysis. Results showed that the groundwater level had a downward trend from 2016 to 2017. The significant downward trend of groundwater levels began in August 2016. The memory effect of groundwater levels was longer under the effect of the drainage tunnel. Before the construction of the drainage tunnel, the response time of groundwater to rainfall was less than 3 hr and rainfall can generate dramatic groundwater level variations. After the drainage tunnel was completed, time lags can be observed in the groundwater response, and the variation of groundwater levels was smaller than before. A strong correlation was found between groundwater levels and the landslide movement. This study demonstrated that the drainage tunnel had effectively controlled the groundwater level in the landslide and ensured the stability of the landslide.
Under the effect of a drainage tunnel, the groundwater level in the landslide area had dropped clearly and had a downward trend. The memory effect of the groundwater level was longer. And the response of groundwater to rainfall was weaker.
•A risk prediction for IDH in HD-patients can be an important tool for clinical work.•LightGBM model plays as an interpretable and best-performing model for the task.•IDH-A and IDH-B model can ...usefully complement each other for risk prediction.
Intradialytic hypotension (IDH) is closely associated with adverse clinical outcomes in HD-patients. An IDH predictor model is important for IDH risk screening and clinical decision-making. In this study, we used Machine learning (ML) to develop IDH model for risk prediction in HD patients.
62,227 dialysis sessions were randomly partitioned into training data (70%), test data (20%), and validation data (10%). IDH-A model based on twenty-seven variables was constructed for risk prediction for the next HD treatment. IDH-B model based on ten variables from 64,870 dialysis sessions was developed for risk assessment before each HD treatment. Light Gradient Boosting Machine (LightGBM), Linear Discriminant Analysis, support vector machines, XGBoost, TabNet, and multilayer perceptron were used to develop the predictor model.
In IDH-A model, we identified the LightGBM method as the best-performing and interpretable model with C- statistics of 0.82 in Fall30Nadir90 definitions, which was higher than those obtained using the other models (P<0.01). In other IDH standards of Nadir90, Nadir100, Fall20, Fall30, and Fall20Nadir90, the LightGBM method had a performance with C- statistics ranged 0.77 to 0.89. As a complementary application, the LightGBM model in IDH-B model achieved C- statistics of 0.68 in Fall30Nadir90 definitions and 0.69 to 0.78 in the other five IDH standards, which were also higher than the other methods, respectively.
Use ML, we identified the LightGBM method as the good-performing and interpretable model. We identified the top variables as the high-risk factors for IDH incident in HD-patient. IDH-A and IDH-B model can usefully complement each other for risk prediction and further facilitate timely intervention through applied into different clinical setting.
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Background
There is an ongoing debate on the off-hour effect on endovascular treatment (EVT) for acute large vessel occlusion (LVO).
Aim
This meta-analysis aimed to compare time metrics and clinical ...outcomes of acute LVO patients who presented/were treated during off-hour with those during working hours.
Summary of review
Structured searches on the PubMed, Embase, Web of Science, and Cochrane Library databases were conducted through 23 February 2021. The primary outcomes were onset to door (OTD), door to imaging, door to puncture (DTP), puncture to recanalization, procedural time, successful recanalization, symptomatic intracranial hemorrhage (SICH), mortality in hospital, good prognosis (90-day modified Rankin Scale (mRS) score 0–2), and 90-day mortality. The secondary outcomes were imaging to puncture (ITP), onset to puncture (OTP), onset to recanalization (OTR), door to recanalization (DTR) time, mRS 0–2 at discharge, and consecutive 90-day mRS score. The odds ratio (OR) and weighted mean difference (WMD) with 95% confidence interval (CI) of the outcomes were calculated using random-effect models. Heterogenicity and publication bias were analyzed. Subgroup and sensitivity analyses were conducted as appropriate. Nineteen studies published between 2014 and 2021 with a total of 14,185 patients were eligible for quantitative synthesis. Patients in the off-hour group were significantly younger than those in the on-hour group and with comparable stroke severity and intravenous thrombolysis rate. The off-hour group had longer OTD (WMD 95% CI, 12.83 1.84–23.82 min), DTP (WMD 95% CI, 11.45 5.93–16.97 min), ITP (WMD 95% CI, 10.39 4.61–16.17 min), OTP (WMD 95% CI, 25.30 13.11–37.50 min), OTR (WMD 95% CI, 25.16 10.28–40.04 min), and DTR (WMD 95% CI, 18.02 10.01–26.03 min) time. Significantly lower successful recanalization rate (OR 95% CI, 0.85 0.76–0.95; p = 0.004; I2 = 0%) was detected in the off-hour group. No significant difference was noted regarding SICH and prognosis. But a trend toward lower OR of good prognosis was witnessed in the off-hour group (OR 95% CI, 0.92 0.84–1.01; p = 0.084; I2 = 0%).
Conclusions
Patients who presented/were treated during off-hour were associated with excessive delays before the initiation of EVT, lower successful reperfusion rate, and a trend toward worse prognosis when compared with working hours. Optimizing the workflows of EVT during off-hour is needed.
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