Assessing the severity of cotton Verticillium wilt disease from in situ canopy images and spectra using convolutional neural networks

Verticillium wilt(VW)is a common soilborne disease of cotton.It occurs mainly in the seedling and bollopening stages and severely impairs the yield and quality of the fiber.Rapid and accurate identification and evaluation of VW severity(VWS)forms the basis of field cotton VW control,which has great significance to cotton production.Cotton VWS values are conventionally measured using in-field observations and laboratory test diagnoses,which require abundant time and professional expertise.Remote and proximal sensing using imagery and spectrometry have great potential for this purpose.In this study,we performed in situ investigations at three experimental sites in 2019 and 2021 and collected VWS values,in situ images,and spectra of 361 cotton canopies.To estimate cotton VWS values at the canopy scale,we developed two deep learning approaches that use in situ images and spectra,respectively.For the imagery-based method,given the high complexity of the in situ environment,we first transformed the task of healthy and diseased leaf recognition to the task of cotton field scene classification and then built a cotton field scenes(CFS)dataset with over 1000 images for each scene-unit type.We performed pretrained convolutional neural networks(CNNs)training and validation using the CFS dataset and then used the networks after training to classify scene units for each canopy.The results showed that the Dark Net-19 model achieved satisfactory performance in CFS classification and VWS values estimation(R^(2)=0.91,root-mean-square error(RMSE)=6.35%).For the spectroscopy-based method,we first designed a one-dimensional regression network(1D CNN)with four convolutional layers.After dimensionality reduction by sensitive-band selection and principal component analysis,we fitted the 1D CNN with varying numbers of principal components(PCs).The 1D CNN model with the top 20 PCs performed best(R^(2)=0.93,RMSE=5.77%).These deep learning-driven approaches offer the potential of assessing crop disease severity from spatial and spectral perspectives.

Raindrop Size Distribution Measurements at High Altitudes in the Northeastern Tibetan Plateau during Summer

Characteristics of raindrop size distribution during summer are studied by using the data from six Parsivel disdrometers located in the northeastern Tibetan Plateau.The analysis focuses on convective and stratiform precipitation at high altitudes from 2434 m to 4202 m.The results show that the contribution of stratiform and convective precipitation with rain rate between 1≤R<5 mm h^(-1) to the total precipitation increases with altitude,and the raindrop scale and number concentration of convective precipitation is larger than that for stratiform precipitation.The droplet size spectra of both stratiform and convective precipitation shows a single peak with a peak particle size between 0.31–0.50 mm,and they have essentially the same peak particle size and number concentration at the same altitude.The maximum spectral widths of stratiform clouds are between 4 mm and 5 mm,while those of convective clouds range from 4 mm to 8 mm.The Gamma distribution is more suitable than the Marshall-Palmer distribution in terms of the actual raindrop spectrum distribution.The stratiform precipitation particles are smaller with higher number concentration,while the opposite is true for the convective precipitation particles.The convective precipitation particles drop faster than stratiform precipitation particles when the particle size exceeds 2 mm,and the falling velocity of raindrops after standard curve fitting is underestimated during the observation period.Moreover,conventional radar estimation methods would underestimate the precipitation in the Northeastern Tibetan Plateau.

外周血sPD-L1在小细胞肺癌患者化疗期间变化及其临床意义

目的:肿瘤微环境中,免疫相关机制使程序性死亡分子配体1(programmed death ligand 1,PD-L1)表达上调,从而异常激活PD-L1信号通路,介导肿瘤免疫逃逸。可溶性程序性死亡配体1(soluble programmed death ligand 1,sPD-L1)是PD-L1的一种存在形式。有研究证实sPD-L1在肺鳞癌及腺癌中的表达与疾病进展相关,而小细胞肺癌(small cell lung cancer,SCLC)恶性程度高侵袭性强,相关研究较少。本研究旨在观察sPD-L1在SCLC患者血浆中的表达变化及临床意义。方法:筛选2018年3月至2018年11月山西省肿瘤医院经病理学检查诊断为SCLC的初治患者94例作为试验组,选取同期健康体检者17例作为对照组,比较两组血浆sPD-L1 的动态变化,并分析sPD-L1 表达与TNM 分期、远处转移以及胃泌素释放肽前体(pro-gastrin-releasing peptide,ProGRP)的相关性。结果:SCLC组血浆sPD-L1水平高于健康人组(P<0.05和P<0.01)。疾病缓解期的SCLC患者化疗后血浆sPD-L1水平比化疗前显著降低(P<0.01);疾病进展期患者化疗后血浆sPD-L1水平比化疗前显著升高(P<0.01)。SCLC患者sPD-L1异常高表达与疾病进展显著相关(P<0.05)。血浆sPD-L1表达与肿瘤标志物ProGRP呈正相关。结论:SCLC患者外周血浆sPD-L1的表达较健康人增高,且与疗效密切相关。

PD-1/PD-L1在小细胞肺癌中的临床研究进展

小细胞肺癌(small cell lung cancer,SCLC)恶性程度高,具有强侵袭性、快速增长及早期转移等特点。初始治疗对化疗和放疗较敏感,但易复发且预后差。免疫检测点抑制剂程序性死亡分子-1(programmed death-1,PD-1)和程序性死亡分子1配体(pro-grammed death-ligand 1,PD-L1)拮抗剂,通过激活T细胞对肿瘤细胞的免疫应答,在SCLC的临床研究中均获得了很好的疗效,有望成为治疗SCLC的主要手段。本文旨在阐述PD-1/PD-L1抑制剂在SCLC治疗中的研究进展,同时,比较肿瘤突变负荷(tumormutation burden,TMB)与PD-L1表达作为生物标记物在SCLC的作用。

QL1706 (anti-PD-1 IgG4/CTLA-4 antibody) plus chemotherapy with or without bevacizumab in advanced non-small cell lung cancer: a multi-cohort, phase II study

First-line chemoimmunotherapy(with or without bevacizumab)has improved outcomes in advanced non-small cell lung cancer(NSCLC).Here,this open-label,multi-cohort phase II study(NCT05329025)was done to investigate the safety and efficacy of QL1706(a single bifunctional MabPair product against PD-1 and CTLA-4)and chemotherapy with or without bevacizumab in this population.Patients were enrolled into five different cohorts based on genotype(cohorts 1-4,epidermal growth factor receptor[EGFR]wild-type;cohort 5,EGFR-mutant and progressed on EGFR-tyrosine kinase inhibitors[TKIs]).Between June 11,2021 and December 29,2021,91 patients were enrolled.Most frequent treatment-related adverse events(TRAEs)included decreased appetite(60[65.9%]),anemia(60[65.9%]),infusion-related reactions(48[52.7%]),and pruritus(44[48.4%]).Grade≥3 TRAEs occurred in 30(33.0%)patients.Twenty-seven(45%)patients with wild-type EGFR achieved partial response(PR)(objective response rate[ORR]=45%)and had a median progression-free survival(mPFS)of 6.8 months(95%CI:5.2-9.7).For 31 patients harboring mutated EGFR,17(54.8%)achieved PR(ORR=54.8%),with an mPFS of 8.5 months(95%CI:5.72-not evaluable).Overall,QL1706 plus chemotherapy,regardless of having bevacizumab,was generally tolerable and had promising antitumor activity for EGFR wild-type advanced NSCLC in first-line setting.Moreover,QL1706 plus chemotherapy and bevacizumab showed favorable antitumor activity for patients who had EGFR mutated NSCLC but failed in TKI therapy,demonstrating a potential for treating this population.