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Target detection and tracking algorithms are one of the key technologies in the field of autonomous driving in intelligent transportation, providing important sensing capabilities for vehicle localization and path planning. Siamese network-based trackers formulate the visual tracking mission as an image-matching process by regression and classification branches, which simplifies the network structure and improves the tracking accuracy. However, there remain many problems, as described below. (1) The lightweight neural networks decrease the feature representation ability. It is easy for the tracker to fail under the disturbing distractors (e.g., deformation and similar objects) or large changes in the viewing angle. (2) The tracker cannot adapt to variations of the object. (3) The tracker cannot reposition the object that has failed to track. To address these issues, we first propose a novel match filter arbiter based on the Euclidean distance histogram between the centers of multiple candidate objects to automatically determine whether the tracker fails. Secondly, the Hopcroft-Karp algorithm is introduced to select the winners from the dynamic template set through the backtracking process, and object relocation is achieved by comparing the Gradient Magnitude Similarity Deviation between the template and the winners. The experiments show that our method obtains better performance on several tracking benchmarks, i.e., OTB100, VOT2018, GOT-10k, and LaSOT, compared with state-of-the-art methods.

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OBJECTIVE: To evaluate the epidemiological and morphological characteristics of coronary plaque in diabetic patients with symptomatic coronary heart disease (CHD) by dual-source computed tomography (DSCT). MATERIALS AND METHODS: From June 2013 to December 2014, 267 consecutive patients with type 2 diabetes mellitus were examined by DSCT. Plaque type, distribution, as well as extent and obstructive characteristics were determined for each segment. RESULTS: A total of 225 patients were included in the final study. Among the 225 cases, patients with calcium score >10 accounted for 76.9%. With the increase in calcium score, the number of obstructive stenoses increased from 17 (22.7%) to 150 (66.4%) segments, and non-obstructive stenosis decreased from 58 (77.3%) to 76 (33.6%) segments. A total of 862 (3.8±3.0 per patient) plaques were detected, of which 448 (52%) were calcified plaque, 272 (32%) mixed plaques and 142 (16%) soft plaques. Regarding the stenosis type, there were significantly more mild (54%), followed by moderate (26%) and severe stenosis (20%); 152 (67.6%) patients had .2 vascular lesions, while 73 (32.4%) patients with single diseased vessel. 190 (84.40%) patients with atherosclerotic plaque were located in left anterior descending (LAD) coronary artery, 146 (64.9%) patients in right coronary artery (RCA), 114 (50.7%) patients in left circumflex (LCX) coronary artery. The most common site of all detected plaques was the proximal segment of the LAD (18.7%). CONCLUSION: DSCT showed that coronary arteries of diabetic patients with symptomatic CHD were more prone to calcification. There was more non-obstructive than obstructive lumen narrowing; obstructive stenosis and calcification score was positively correlated; coronary plaques were widely distributed, and mainly located in multiple diseased vessels.

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BACKGROUND: This study aimed to analyse the injuries sustained by rescue workers in earthquake relief efforts in high altitude areas for improving the ways of how to effectively prevent the injuries. METHODS: The clinical data of 207 relief workers from four military hospitals in Tibet, who were injured in the Tibetan disaster areas of China during '4.25' Nepal earthquake rescue period, was retrospectively analyzed. The demographic features, sites of injury and causes of injury were investigated. RESULTS: The most frequently injured sites were the ankle-foot and hand-wrist (n = 61, 26.5 %), followed by injuries in leg-knee-calf (n = 22, 9.6 %), head-neck (4.87 %), thoracic and abdominal region (2.6 %) and lower back (3.9 %). The specific high-altitude environment increased the challenges associated with earthquake relief. DISCUSSION: The specific plateau environment and climate increased the burden and challenge in earthquake relief. The injury distribution data shown in this study demonstrated that effective organization and personnel protection can reduce the injury occurrences. CONCLUSION: Relief workers were prone to suffering various injuries and diseases under specific high-altitude environment.

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Fulvic Acid-Bentonite (FA-BENT) complex was prepared using coprecipitation method, and basic properties of the complex and sorption properties of fluorine at different environmental conditions were studied. XRD results showed that the d001 spacing of FA- BENT complex had no obvious change compared with the raw bentonite, although the diffraction peak intensity of smectite in FA-BENT complex reduced, and indicated that FA mainly existed as a coating on the external surface of bentonite. Some functional groups (such as C==O, −OH, etc. ) of FA were observed in FA-BENT FTIR spectra, thus suggesting ligand exchange-surface complexation between FA and bentonite. Higher initial pH values of the reaction system were in favor of the adsorption of fluorine onto FA-BENT, while the equilibrium capacity decreased with the increase of pH at initial pH ≥ 4.50. The adsorption of fluorine onto FA-BENT was also affected by ionic strength, and the main reason might be the "polarity" effect. The adsorption of fluorine onto FA-BENT followed pseudo-second-order kinetic model and was controlled by chemical process ( R² = 0.999 2). Compared with the Freundlich model, Langmuir model was apparently of a higher goodness of fit (R² > 0.994 9) for absorption of fluorine onto FA-BENT. Thermodynamic parameters indicated that the adsorption process of fluorine was an spontaneously endothermic reaction, and was an entropy-driven process (ΔH 32.57 kJ · mol⁻¹, ΔS 112.31 J · (mol · K)⁻¹, ΔG −0.65- −1.76 kJ · mol⁻¹).

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AIMS: The cardiovascular risk factors and diabetic complications are related to coronary atherosclerosis. However, the evaluation of the prevalence of coronary atherosclerosis based on their accumulation remains to be determined. METHODS: 247 consecutive Chinese subjects with type 2 diabetes but without history of coronary heart disease (CHD) underwent 320-slice computed tomographic coronary angiography, including no coronary atherosclerosis, non-obstructive atherosclerosis (<50% stenosis) and obstructive atherosclerosis (≥50% stenosis). Conventional cardiovascular risk factors, albuminuria, renal dysfunction and diabetic retinopathy (DR) were determined. Framingham Risk Score (FRS) was used to assess the 10-year CHD risk. RESULTS: Increase in burden of cardiovascular risk factors and diabetic complications were significantly associated with the likelihood of being a higher coronary atherosclerosis category. In the analysis for trend through the categories of burden score or FRS stratification, the percentage of obstructive atherosclerosis was increased and the percentage of no atherosclerosis decreased as the burden score and FRS increased (all p<0.005), respectively. The areas under the receiver operator curve for the burden score versus FRS were greater at predicting coronary atherosclerosis and obstructive atherosclerosis (p=0.004 and p=0.002), respectively. CONCLUSIONS: The prevalence of coronary atherosclerosis was increased with the accumulation of cardiovascular risk factors and diabetic complications. The burden of these clinical and biochemical risk factors has increased ability for prediction of the presence and severity of coronary atherosclerosis over FRS in type 2 diabetic patients.

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RATIONALE: Qualitatively, FLAIR MR imaging is sensitive to the detection of hippocampal sclerosis (HS). Quantitative analysis of T2 maps provides a useful objective measure and increased sensitivity over visual inspection of T2-weighted scans. We aimed to determine whether quantification of normalised FLAIR is as sensitive as T2 mapping in detection of HS. METHOD: Dual echo T2 and FLAIR MR images were retrospectively analysed in 27 patients with histologically confirmed HS and increased T2 signal in ipsilateral hippocampus and 14 healthy controls. Regions of interest were manually segmented in all hippocampi aiming to avoid inclusion of CSF. Hippocampal T2 values and measures of normalised FLAIR Signal Intensity (nFSI) were compared in healthy and sclerotic hippocampi. RESULTS: HS was identified on T2 values with 100% sensitivity and 100% specificity. HS was identified on nFSI measures with 60% sensitivity and 93% specificity. CONCLUSION: T2 mapping is superior to nFSI for identification of HS.

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PRIMARY OBJECTIVE: To investigate the epidemiology of TBI in Chinese inpatients. RESEARCH DESIGN: Civilian inpatients of Chinese military hospitals diagnosed with TBI between 2001-2007 were identified using ICD-9-CM codes. METHODS AND PROCEDURES: Demographic characteristics, admission time, injury cause, injury severity, length of stay and outcomes were compared between ICD-9-CM diagnosis groups. MAIN OUTCOMES AND RESULTS: In total, 203 553 civilian patients with TBI (74.86% male, 25.14% female) were identified from >200 Chinese military hospitals. TBI diagnoses increased by a mean of 4.67% each year. Admission peaked during the third quarter of the year and October annually. The leading causes of TBI were motor vehicle-traffic (51.41%), falls (21.49%) and assaults (15.77%). TBI was categorized by abbreviated injury scale score as mild in 36.64%, serious in 20.13%, severe in 26.81% and critical in 15.68% of inpatients. The mean length of stay was 17.8 ± 24.1 days. Recovery rate was 93.06% and mortality was 4.14%. CONCLUSIONS: The epidemiological data may contribute to the development of effective, targeted strategies to prevent TBI.

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PURPOSE: To evaluate the clinical value of 320-detector row CT in transcatheter arterial chemoembolization (TACE) treatment for hepatocellular carcinoma (HCC). MATERIALS AND METHODS: Sixty-four patients with HCC underwent CT perfusion scanning with a 320-detector row CT before and after TACE. With the help of built-in dual-source CT perfusion software, color perfusion images of hepatic arterial perfusion (HAP), portal vein perfusion (PVP) and hepatic arterial perfusion index (HAPI) of all HCC lesions were obtained, and the above perfusion parameters were measured on the color images. The parameters obtained after TACE were compared with those obtained before TACE, and the differences were statistically analyzed. RESULTS: There were significant differences in HAP, PVP and HAPI between cancer tissues and non-cancerous tissues before TACE (P < 0.05). HCC necrotic tissues had no blood perfusion after TACE. Lower HAP and HAPI and higher PVP were observed in active cancer tissues after operation as compared with those before operation. CONCLUSIONS: The 320-row CT upper abdominal one-stop examination can display the whole liver perfusion well, especially the abnormal perfusion of HCC tissues and postoperative active tissues. Angiography can display the hepatic and nutrient arteries of tumors from three dimensions, and has important guiding significance in preoperative evaluation and postoperative follow up of TACE.

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PURPOSE: The role of spot sign on computed tomography angiography (CTA) for predicting hematoma expansion (HE) after primary intracerebral hemorrhage (ICH) has been the focus of many studies. Our study sought to evaluate the predictive accuracy of spot signs for HE in a meta-analytic approach. MATERIALS AND METHODS: The database of Pubmed, Embase, and the Cochrane Library were searched for eligible studies. Researches were included if they reported data on HE in primary ICH patients, assessed by spot sign on first-pass CTA. Studies with additional data of second-pass CTA, post-contrast CT (PCCT) and CT perfusion (CTP) were also included. RESULTS: 18 studies were pooled into the meta-analysis, including 14 studies of first-pass CTA, and 7 studies of combined CT modalities. In evaluating the accuracy of spot sign for predicting HE, studies of first-pass CTA showed that the sensitivity was 53% (95% CI, 49%-57%) with a specificity of 88% (95% CI, 86%-89%). The pooled positive likelihood ratio (PLR) was 4.70 (95% CI, 3.28-6.74) and the negative likelihood ratio (NLR) was 0.44 (95% CI, 0.34-0.58). For studies of combined CT modalities, the sensitivity was 73% (95% CI, 67%-79%) with a specificity of 88% (95% CI, 86%-90%). The aggregated PLR was 6.76 (95% CI, 3.70-12.34) and the overall NLR was 0.17 (95% CI 0.06-0.48). CONCLUSIONS: Spot signs appeared to be a reliable imaging biomarker for HE. The additional detection of delayed spot sign was helpful in improving the predictive accuracy of early spot signs. Awareness of our results may impact the primary ICH care by providing supportive evidence for the use of combined CT modalities in detecting spot signs.

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PURPOSE: Differentiation of high-grade gliomas and solitary brain metastases is an important clinical issue because the treatment strategies differ greatly. Our study aimed to investigate the potential value of diffusion tensor imaging (DTI) in differentiating high-grade gliomas from brain metastases using a meta-analytic approach. MATERIALS AND METHODS: We searched Pubmed, Embase and the Cochrane Library for relevant articles published in English. Studies that both investigated high-grade gliomas and brain metastases using DTI were included. Random effect model was used to compare fractional anisotropy (FA) and mean diffusivity (MD) values in the two tumor entities. RESULTS: Nine studies were included into the meta-analysis. In the peritumoral region, compared with brain metastases, high-grade gliomas had a significant increase of FA (SMD  = 0.47; 95% CI, 0.22-0.71; P<0.01) and a significant decrease of MD (SMD  = -1.49; 95% CI, -1.91 to -1.06; P<0.01). However, in the intratumoral area, no significant change in FA (SMD  = 0.16; 95% CI, -0.49 to 0.82; P = 0.73) or MD (SMD  = 0.34; 95% CI, -0.91 to 1.60; P = 0.59) was detected between gliomas and metastases. CONCLUSIONS: High-grade gliomas may be distinguished from brain metastases by comparing the peritumoral FA and MD values. DTI appears to be a promising tool in diagnosing solitary intracranial lesions.

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BACKGROUND: Lower extremity atherosclerosis (LEA) is among the most serious diabetic complications and leads to non-traumatic amputations. The recently developed dual-source CT (DSCT) and 320- multidetector computed tomography (MDCT) may help to detect plaques more precisely. The aim of our study was to evaluate the differences in LEA between diabetic and non-diabetic patients using MDCT angiography. METHODS: DSCT and 320-MDCT angiographies of the lower extremities were performed in 161 patients (60 diabetic and 101 non-diabetic). The plaque type, distribution, shape and obstructive natures were compared. RESULTS: Compared with non-diabetic patients, diabetic patients had higher peripheral neuropathy, history of cerebrovascular infarction and hypertension rates. A total of 2898 vascular segments were included in the analysis. Plaque and stenosis were detected in 681 segments in 60 diabetic patients (63.1%) and 854 segments in 101 non-diabetic patients (46.9%; p <0.05). Regarding these plaques, diabetic patients had a higher incidence of mixed plaques (34.2% vs. 27.1% for non-diabetic patients). An increased moderate stenosis rate and decreased occlusion rate were observed in diabetic patients relative to non-diabetic patients (35.8% vs. 28.3%; and 6.6% vs. 11.4%; respectively). In diabetic patients, 362 (53.2%) plaques were detected in the distal lower leg segments, whereas in non-diabetic patients, 551 (64.5%) plaques were found in the proximal upper leg segments. The type IV plaque shape, in which the full lumen was involved, was detected more frequently in diabetic patients than in non-diabetic patients (13.1% vs. 8.2%). CONCLUSION: Diabetes is associated with a higher incidence of plaque, increased incidence of mixed plaques, moderate stenosis and localisation primarily in the distal lower leg segments. The advanced and non-invasive MDCT could be used for routine preoperative evaluations of LEA.

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BACKGROUND: The cerebrovasuclar artery disease as a common complication of type-2 diabetes mellitus (T2DM) caused huge economic burden and lives threatening to patients. We evaluated the prevalence and morphology of carotid and cerebrovascular atherosclerotic plaques in T2DM patients with transient ischemic attack (TIA) or stroke using multidetector CT (MDCT). METHODS: 64-MDCT and dual-source CT (DSCT) angiographies were performed in 195 T2DM patients with TIA or stroke (mean age 65.7+/-12.8 years; 118 men) between January 2009 to August 2011. During the process, plaque type, its distribution, extensive and obstructive natures were determined for each segment derived from the patients. RESULTS: Atherosclerotic plaques were detected in 183 (93.8%) patients. A total of 1056 segments with plaque were identified, of which 450 (42.6%) were non-calcified, 192 (18.2%) were mixed and 414 (39.2%) calcified ones. Among them, 562 (53.2%) resulted in mild stenosis, 291 (27.6%) moderate stenosis, 170 (16.1%) severe stenosis and 33 (3.1%) occlusion. Non-calcified plaques contributed 91.8% to non-obstructive lumen narrowing, while mixed and calcified plaques contributed 89.0% and 65.0% respectively. CONCLUSIONS: MDCT angiography detected a high prevalence of plaques in T2DM patients with TIA or stroke. A relatively high proportion of plaques were non-calcified, as well as with non-obstructive stenosis. MDCT angiography might further enhance the detection and management of carotid and cerebrovascular atherosclerosis in T2DM patients with TIA and stroke.

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PURPOSE: To clarify the differences of the carotid and cerebrovascular disease between patients with and without type 2 diabetes using dual-source CT angiography. MATERIALS AND METHODS: Dual-source CT angiography of the carotid and cerebrovascular arteries was performed in 79 type 2 diabetic patients and 207 non-diabetic patients. The type, extent and distribution of plaques, and luminal stenosis were compared. RESULTS: Compared with non-diabetic patients, diabetic patients had a higher overall incidence of plaque (p<0.05) and cerebral infarction (p<0.05). Among these plaques, no differences were observed in the subtype of plaques between these two cohorts (all p>0.05), as well as for the number of diseased segments and the distribution of plaques; both mainly involved the bilateral cavernous segment of the internal carotid artery. As for the stenosis, non-obstructive lesions were more common in diabetic patients (p<0.05). There was no difference in the segment number of stenosis (≥30% and ≥70%) between these two groups (all p>0.05). CONCLUSION: Diabetes is associated with a higher incidence of plaque and non-obstructive stenosis. However, no significant differences were observed in the type, extent and distribution of involved plaques between diabetic and non-diabetic patients.

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BACKGROUND: Plaque morphology directly correlates with risk of embolism and the recently developed dual-source computed tomography angiography (DSCTA) may help to detect plaques more precisely. The aim of our study was to evaluate the prevalence and morphology of carotid and cerebrovascular atherosclerotic plaques in patients with symptomatic type 2 diabetes mellitus (DM) by DSCTA. METHODS: From July 2009 to August 2010, DSCTA was prospectively performed in 125 consecutive patients with symptomatic type 2 DM. We retrospectively analyzed plaque type, distribution, and extensive and obstructive natures were determined for each segment for all patients. RESULTS: Atherosclerotic plaques were detected in 114 (91.2%) patients. Relatively more noncalcified (45%) and calcified (39%) plaques and less mixed (16%) plaques were observed (p < 0.001). Noncalcified plaques were found mainly in the intracranial arteries (81.8%), mixed plaques in the intracranial arteries (25.2%) and intracranial internal carotid artery (ICA) (56.1%). Calcified plaques were found mainly in the intracranial ICA (65.9%) and extracranial arteries (28.2%) (for all, p < 0.001). Extension of plaques from the 1(st) to 5(th) segments was observed in 67 (58.8%) patients and from the 6(th) to 10(th) segments in 35 (30.7%) patients. The most common site of all detected plaques was the cavernous segment. Regarding stenosis, there were significantly more nonobstructive than obstructive stenosis (91% vs. 9%, p < 0.001). CONCLUSION: DSCTA detected a high prevalence of plaques in patients with symptomatic type 2 DM. A relatively high proportion of plaques were noncalcified, as well as with nonobstructive stenosis. The distribution of plaques was extensive, with the cavernous portion of ICA being the most common site.

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BACKGROUND: Coronary artery disease (CAD) is a common and severe complication of type 2 diabetes mellitus (DM). The aim of this study is to identify the features of CAD in diabetic patients using coronary CT angiography (CTA). METHODS: From 1 July 2009 to 20 March 2010, 113 consecutive patients (70 men, 43 women; mean age, 68 ± 10 years) with type 2 DM were found to have coronary plaques on coronary CTA. Their CTA data were reviewed, and extent, distribution and types of plaques and luminal narrowing were evaluated and compared between different sexes. RESULTS: In total, 287 coronary vessels (2.5 ± 1.1 per patient) and 470 segments (4.2 ± 2.8 per patient) were found to have plaques, respectively. Multi-vessel disease was more common than single vessel disease (p < 0.001), and the left anterior descending (LAD) artery (35.8%) and its proximal segment (19.1%) were most frequently involved (all p < 0.001). Calcified plaques (48.8%) were the most common type (p < 0.001) followed by mixed plaques (38.1%). Regarding the different degrees of stenosis, mild narrowing (36.9%) was most common (p < 0.001); however, a significant difference was not observed between non-obstructive and obstructive stenosis (50.4% vs. 49.6%, p = 0.855). Extent of CAD, types of plaques and luminal narrowing were not significantly different between male and female diabetic patients. CONCLUSIONS: Coronary CTA depicted a high plaque burden in patients with type 2 DM. Plaques, which were mainly calcified, were more frequently detected in the proximal segment of the LAD artery, and increased attention should be paid to the significant prevalence of obstructive stenosis. In addition, DM reduced the sex differential in CT findings of CAD.

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Immortalized F(2) population of rice (Oryza sativa L.) was developed by randomly mating F(1) among recombinant inbred (RI) lines derived from (Zhenshan 97B x Minghui 63), which allowed replications within and across environments. QTL (quantitative trait loci) mapping analysis on kilo-grain weight of immortalized F(2) population was performed by using newly developed software for QTL mapping, QTLMapper 2.0. Eleven distinctly digenic epistatic loci included a total of 15 QTL were located on eight chromosomes. QTL main effects of additive, dominance, and additive x additive, additive x dominance, and dominance x dominance interactions were estimated. Interaction effects between QTL main effects and environments (QE) were predicted. Less than 40% of single effects, most of which were additive effects, for identified QTL were significant at 5% level. The directional difference for QTL main effects suggested that these QTL were distributed in parents in the repulsion phase. This should make it feasible to improve kilo-grain weight of both parents by selecting appropriate new recombinants. Only few of the QE interaction effects were significant. Application prospect for QTL mapping achievements in genetic breeding was discussed.

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