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For classification of wood species with similar microstructure, 19 high-value hardwood species of Papilionaceae, Ebenaceae, and Caesalpiniaceae were used as experimental objects. Images of transverse sections, radial sections, and tangential sections were collected by Micro CT. Local binary patterns (LBP) are often used for feature extraction. LBP deformed forms such as uniform LBP, rotation-invariant LBP, and rotation-invariant uniform LBP were fused with Gray-Level Co-Occurrence Matrix (GLCM) to form three fusion features. The fusion features were combined with support vector machine (SVM) or BP neural network to realize wood classification. The texture feature fusion method was found to be better than the single feature classification. Among them, the effect of uniform LBP and GLCM fusion was the best, and the classification accuracy combined with SVM was the highest. The evaluation of the classification of 19 kinds of hardwood mainly depended on transverse sections, and its accuracy was higher than that of the radial and tangential sections. Therefore, the classification results of transverse sections should be taken as the main evaluation basis for the classification of the 19 high-value hardwood species.

This phase II randomized clinical trial aimed to assess the efficacy and toxicity of Endostar, an antiangiogenesis inhibitor, combined with concurrent chemoradiotherapy (CCRT) for locally advanced cervical cancer (LACC). Patients with LACC were randomly assigned to either CCRT plus Endostar (CCRT+E arm) or CCRT alone (CCRT arm). All patients received pelvic intensity-modulated radiation therapy (IMRT) and brachytherapy. Weekly cisplatin was administered concurrently with IMRT. Patients in the CCRT+E arm also received concurrent Endostar every 3 weeks for two cycles. The primary endpoint was progression-free survival (PFS) and acute toxicities. The exploratory endpoint was the impact of vascular endothelial growth factor receptor-2 (VEGFR2) expression on long-term survival. A total of 116 patients were enrolled. Patients in the CCRT+E arm and in the CCRT arm had similar acute and late toxicity profile. The 1- and 2-year PFS were 91.4% versus 82.1% and 80.8% versus 63.5% (p=0.091), respectively. The 1- and 2-year distance metastasis-free survival (DMFS) were 92.7% versus 81.1% and 86.0% versus 65.1% (p=0.031), respectively. Patients with positive VEGFR2 expression had significant longer PFS and overall survival (OS) compared with those with negative VEGFR2 expression. Patients in the CCRT+E arm had significantly longer PFS, OS, and DMFS than those in the CCRT arm when VEGFR2 expression was positive. In conclusion, CCRT plus Endostar significantly improved DMFS but not PFS over CCRT alone. The addition of Endostar could significantly improve survival for patients with positive VEGFR2 expression.

Heming Lu,1,* Yuying Wu,2,* Xu Liu,1 Huixian Huang,1 Hailan Jiang,1 Chaohua Zhu,1 Yuping Man,3 Pei Liu,4 Xianglong Li,1 Zhaohong Chen,1 Xianfeng Long,1 Qiang Pang,1 Shan Deng,1 Junzhao Gu1 1Department of Radiation Oncology, People’s Hospital of Guangxi Zhuang Autonomous Region, Nanning, 530021, People’s Republic of China; 2Department of Gynecology, People’s Hospital of Guangxi Zhuang Autonomous Region, Nanning, 530021, People’s Republic of China; 3Department of Radiology, People’s Hospital of Guangxi Zhuang Autonomous Region, Nanning, 530021, People’s Republic of China; 4Department of Oncology, Youjiang Medical University for Nationalities, Baise, 533000, People’s Republic of China*These authors contributed equally to this workCorrespondence: Heming LuDepartment of Radiation Oncology, People’s Hospital of Guangxi Zhuang Autonomous Region, No. 6 Taoyuan Road, Nanning, 530021, People’s Republic of ChinaTel +86-771-218-6806Email luhming3632@163.comPurpose: To evaluate the role of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) in predicting early treatment response.Materials and Methods: Patients with locally advanced cervical cancer (LACC) treated with concurrent chemoradiotherapy (CCRT) were enrolled. Pelvic DCE-MRI scans were performed before RT (pre-RT), in the middle of RT (mid-RT), and at the end of RT (post-RT), separately. Parameters (ie, Ktrans, Kep, and Ve) were measured. Pre-, mid-, and post-RT Ktrans were denoted as Ktrans-preTx, Ktrans-midTx, and Ktrans-postTx, respectively. And the same denoting rule also went for Kep and Ve. Difference for the same parameter such as Ktrans measured between two consecutive time points was calculated as second Ktrans value minus first Ktrans value. The differences in Ktrans between pre-RT and post-RT, between pre-RT and mid-RT, and between mid-RT and post-RT were denoted as ΔKtrans-post-preTx, ΔKtrans-mid-preTx, and ΔKtrans-post-midTx, respectively, and the same denoting rule was also applied to Kep and Ve.Results: A total of 57 patients were enrolled. After the treatment, 31 patients had complete response (CR group). The remaining 26 patients had partial response (NCR group). Significant differences were found in Ktrans-postTx, Kep-postTx, Ve-midTx, ΔKtrans-post-preTx, ΔKtrans-post-midTx, ΔKep-post-preTx, ΔKep-mid-preTx and ΔKep-post-midTx between the two groups. Receiver operating characteristic (ROC) analysis for their performances in predicting treatment response showed an area under curve (AUC) of 0.656– 0.849, sensitivity of 61.3– 93.5%, specificity of 46.1– 73.1%, and maximal Youden Index of 36.5– 66.6. Among those parameters, Kep-postTx was the best, and its AUC, sensitivity, specificity, maximal Youden Index, and cutoff value were 0.849, 87.1%, 73.1%, 60.2, and 0.341, respectively. These combined parameters showed an AUC of 0.952, with sensitivity of 87.1%, specificity of 96.1%, and maximal Youden Index of 83.2.Conclusion: DCE-MRI parameters can predict early treatment outcome. Among those parameters, Kep-postTx is the best predictor. The combination of multi-parameters can increase the predictive potency.Keywords: cervical cancer, locally advanced disease, dynamic contrast-enhanced magnetic resonance imaging, concurrent chemoradiotherapy, prognosis prediction

The demand for leaf area index (LAI) retrieval from spaceborne full-waveform LiDAR increases due to its direct sampling of the three-dimensional forest structure at a near-global scale. However, the nonrandomness (i.e., clumping effect) of canopy composition limits the reliability of LAI derived from two common methods. They either assume a homogeneous scene in the footprint or just correct for the large gaps-induced between-crown clumping. The clumping in the crown is still an unaddressed issue. We proposed a method to compensate occlusion (i.e., lower canopy layers are occluded by the upper canopy in the process of LiDAR measurement), through which the vertical canopy profile can be resolved from the waveform. Further, we developed a method of deriving relative path length distribution that can reflect the heterogeneity of the canopy from the occlusion-corrected waveform. In addition to correcting the between-crown clumping, we corrected the within-crown clumping further using the derived relative path length distribution, based on path length distribution (PATH) theory. We used simulated waveform data with known LAI and GLAS data with corresponding field-measured LAI to test the performance of our and the other two common LAI retrieval methods. Results show that the errors of our approach are the lowest (with an error generally below 10% and the maximum error below 20%, compared with up to 69% and 47% for the other two methods), and it is relatively stable in various scenes. This study demonstrated the potential of improving LAI retrieval through full utilization of full-waveform data.

Defeng Qing,1,* Yuying Wu,2,* Xu Liu,1,* Hailan Jiang,1,* Chaohua Zhu,1,* Pei Liu,3 Junming Dang,4 Xianglong Li,1 Zhaohong Chen,1 Xianfeng Long,1 Qiang Pang,1 Luxing Peng,1 Shan Deng,1 Junzhao Gu,1 Renfeng Zhao,2 Changyi Chen,2 Heming Lu1 1Department of Radiation Oncology, People’s Hospital of Guangxi Zhuang Autonomous Region, Nanning 530021, People’s Republic of China; 2Department of Gynecology, People’s Hospital of Guangxi Zhuang Autonomous Region, Nanning 530021, People’s Republic of China; 3Department of Radiation Oncology, Youjiang Medical University for Nationalities, Baise 533000, People’s Republic of China; 4Department of Oncology, Guangxi University of Chinese Medicine, Nanning 530001, People’s Republic of China*These authors contributed equally to this workCorrespondence: Heming LuDepartment of Radiation Oncology, People’s Hospital of Guangxi Zhuang Autonomous Region, Nanning City 530021, People’s Republic of ChinaTel +86-771-218-6504Email luhming3632@163.comPurpose: We aimed to evaluate the long-term survival outcomes of concurrent chemoradiotherapy (CCRT) combined with nimotuzumab followed by surgery in patients with locally advanced cervical cancer (LACC).Patients and Methods: Patients received whole pelvic intensity-modulated radiation therapy (IMRT) and concomitantly with weekly cisplatin (40 mg/m2) or nedaplatin (30 mg/m2) and weekly nimotuzumab (200 mg). After assessment of the treatment response, patients then underwent radical surgery.Results: Between June 2013 and July 2016, 33 patients with FIGO IB2–IIIB cervical cancer were recruited. Clinical complete response and partial response were observed in 8 (24.3%) and 23 patients (69.7%), respectively. Twenty-seven patients (81.8%) were successfully treated with radical hysterectomy and pelvic lymphadenectomy: 9 (33.3%) showed pathological complete response; 10 (37.1%) showed partial response and 8 (29.6%) presented with persistent macroscopic/microscopic residual carcinoma. For the intention-to-treat population, the median follow-up time was 53.7 months. Locoregional recurrence and distant metastases were observed in three and seven patients, respectively. The 5-year overall survival, progression-free survival, locoregional recurrence-free survival, and distant metastasis-free survival were 81.5%, 72.7%, 90.9%, and 78.3%, respectively. Both acute and late toxicities were manageable and mainly limited to grade 1 or 2.Conclusion: Concurrent chemoradiotherapy combined with nimotuzumab followed by surgery for patients with LACC is safe and results in excellent long-term treatment outcomes. Further randomized controlled studies are warranted to confirm the findings.Keywords: locally advanced cervical cancer, neoadjuvant chemotherapy, intensity-modulated radiotherapy, anti-EGFR monoclonal antibody, radical surgery

Background To investigate the differences between physicians in target delineation in intensity-modulated radiation therapy for nasopharyngeal carcinoma as well as their impact on target dose coverage. Methods Ninety-nine in-hospital patients were randomly selected for retrospective analysis, and the target volumes were delineated by 2 physicians. The target volumes were integrated with the original plans, and the differential parameters, including the Dice similarity coefficient (DSC), Hausdorff distance (HD), and Jaccard similarity coefficient (JSC) were recorded. The dose–volume parameters to evaluate target dose coverage were analyzed by superimposing the same original plan to the 2 sets of images on which the target volumes were contoured by the 2 physicians. The significance of differences in target volumes and dose coverage were evaluated using statistical analysis. Results The target dose coverage for different sets of target volumes showed statistically significant differences, while the similarity metrics to evaluate geometric target volume differences did not. More specifically, for PGTVnx, the median DSC, JSC, and HD were 0.85, 0.74, and 11.73, respectively; for PCTV1, the median values were 0.87, 0.77, and 11.78, respectively; for PCTV2, the median values were 0.90, 0.82, and 16.12, respectively. For patients in stages T3-4, DSC, and JSC were reduced but HD was increased compared to those in stages T1-2. Dosimetric analysis indicated that, for the target volumes, significant differences between the 2 physicians were found in D95, D99, and V100 for all the target volumes (ie, PGTVnx, PCTV1, and PCTV2) across the whole group of patients, as well as in patients with disease stages T3-4 and T1-2. Conclusions The target volumes delineated by the 2 physicians had a high similarity, but the maximal distances between the outer contours of the 2 sets were significantly different. In patients with advanced T stages, significant differences in dose distributions were found, stemming from the deviations of target delineation.

Leaf inclination angle distribution plays an important role in indirect leaf area measurement methods. Path length distribution method (PATH) is an indirect leaf area measurement method based on Beer's Law, which has been applied to isolated trees with Terrestrial Laser Scanning (TLS). However, it can only set the leaf projection G to a constant value. In this paper, the PATH method considering leaf inclination models is introduced, which allows the G function to be a variable corresponding to leaf inclination. On the basis of this method, this paper explores the effect of different leaf inclination angle distribution assumptions on the inversion of the leaf area of isolated trees based on TLS. The results show that compared with the measured leaf inclination, the relative errors of the inversion results based on the six typical leaf inclination assumptions are between −14.3 % to +41.2%, which indicates that leaf inclination has a significant effect on the inversion of the leaf area. Further, experiments in this paper show that the mean value of the G function is a relatively accurate representation of it.

Leaf area index (LAI) is a key parameter of vegetation structure in the fields of agriculture, forestry, and ecology. Optical indirect methods based on the Beer-Lambert law are widely adopted in numerous fields given their high efficiency and feasibility for LAI estimation. These methods have undergone considerable progress in the past decades, thereby making them operational in ground-based LAI measurement and even in airborne estimation. However, several challenges remain, given the requirement of increasing accuracy and new applications. Clumping effect correction attained significant progress for continuous canopies with non-randomly disturbed leaves while non-continuous canopies are rarely studied. Convenient and operational measurement of leaf angle distribution and woody components is lacked. Accurate and comprehensive validations are still very difficult due to the limitations of direct measurement. The introduction of active laser scanning technology is a driving force for addressing several challenges, but its three-dimensional information has not been fully explored and utilized. In order to update the general knowledge and identify the possible error source, this study comprehensively reviews the temporal development, theoretical framework, and issues of indirect LAI measurement, followed by current methods, instruments, and platforms. Latest methods and instruments are introduced and compared to traditional ones. Current challenges, recent advances, and future perspectives are discussed to provide recommendations for further research.

Additional file 1. Graduation Survey for International Medical Students.

How to test the effect of density estimation methods is the key problem in the statistics. This paper presents a new criterion for assessing the effect of density estimation to select the suitable density e stimation method, using the maximum-entropy non-Gaussian measurement. Comparing withχ 2 -test and Dn-test, the method avoids the problem of the data interval division, and it is su itable for any type probability distribution. Simulation results show that the proposed me thod can accurately discriminate the pros and cons of different density estimation methods..

Background To determine appropriate timing of an adaptive radiation therapy (ART) replan by evaluating anatomic and dosimetric changes of target volumes and organs at risk (OARs) during intensity-modulated radiation therapy (IMRT) for nasopharyngeal carcinoma (NPC). Methods Nineteen NPC patients were recruited. Each patient had repeat computed tomography (CT) scans after each five fractions and at treatment completion. Automatic re-contouring the targets and OARs by using deformable registration algorithm was conducted through CT-CT fusion. Anatomic changes were assessed by comparing the initial CT and repeated CT. Hybrid plans with re-contouring were generated and the dose-volume histograms (DVH) of the hybrid plan and the original plan were compared. Results Progressive volume reductions in gross target volume for primary disease (GTVnx), gross target volume for involved lymph nodes (GTVnd), and parotids were observed over time. Comparing with the original plan, each hybrid plan had no significant difference in homogeneity index (HI) for all the targets. Some parameters for planning target volumes for primary disease and high-risk clinical target volume (PTVnx and PTV1, respectively) improved significantly, notably starting from the 10th fraction. These parameters included mean dose (Dmean), dose to 95 % of the volume (D95), percentage of the volume receiving 95 % of the prescription dose (V95), and conformity index (CI) for PTVnx, and Dmean, D95, and CI for PTV1. The dosimetric parameters for PTVnd remained the same in general except for D95 and V95 which had significant improvement at specific time points; whereas for PTV2, similar trend of dosimetric changes was also observed. Dose to some OARs increased significantly at some time points. Conclusions There were significant anatomic and dosimetric changes in the targets and OARs. The target dose coverage in the hybrid plans did not get worse, but overdose occurred in some critical structures. Significant dosimetric changes should be considered as a trigger point at which ART replanning is indicated. D95/V95/CI for PTV2, Dmax for the brain stem, spinal cord, right eyeball and left lens, and Dmean/V30 for the parotids and glottis were taken into account for predicting the need for ART. Two replans at the 5th and 15th fractions were suggested.

e17000 Background: This study was to investigate the efficacy and safety of neoadjuvant chemoradiotherapy plus nimotuzumab followed by surgery for advanced cervical cancer. Methods: The inclusion criteria of this study were as follows: age: 18-75 years old; ECOG 0-1; FIGO stages IB2-IIIB; not eligible for surgery. IMRT with a total dose of 50-54 Gy was delivered to the tumor and the whole uterus, and 45-48.6 Gy to the high-risk regions. Weekly cisplatin or nedaplatin was administered concurrently with IMRT. Weekly nimotuzumab was given for 6 cycles. Patients were then assessed for clinical tumor response and operability. For those who were candidates for surgery, radical hysterectomy and pelvic lymph node dissection were performed 5-6 weeks after the completion of neoadjuvant therapy. Results: Twenty-eight patients were enrolled. Stage distributions were as follows: IB2, 3 pts; IIA, 5 pts; IIB, 16 pts; IIIA, 2 pts; IIIB, 2 pts. Twenty six (92.8%) patients completed ≥ 5 cycles of chemotherapy, and all completed ≥5 cycles of nimotuzumab. Complete clinical response and partial response were found in 8 patients (28.5%) and 20 patients (71.5%), respectively. Four patients were not eligible for surgery and 2 candidates refused surgery. They were not included in this analysis. Radical surgery was performed for the remaining 22 patients. Among them, 8 (36.4%) had complete pathology response, 9 (40.9%) presented with persistent atypical cells or cervical intraepithelial neoplasia, and 5 (22.7%) presented with macroscopic and/or microscopic residual disease. Median follow-up was 22 months (range, 5-39 months). The 2-year locoregional control rate, progression-free survival rate, distant metastasis-free survival rate, and overall survival rate were 95.0%, 85.2%, 84.0%, and 90.0%, respectively. Acute toxicity profiles were mainly manifested as marrow suppression, nausea, diarrhea, and loss of appetite. They were mild in general and easily manageable. Chronic toxicities were mainly limited to grade 1. No severe late toxicities were observed Conclusions: This treatment approach is highly effective and safe in advanced cervical cancer. Further studies are warranted to confirm the findings. Clinical trial information: NCT01938105.