Follicular hyperandrogenism and insulin resistance in polycystic ovary syndrome patients with normal circulating testosterone levels

Polycystic ovary syndrome（PCOS） is a common reproductive disease with high heterogeneity. The role of excess androgen in PCOS etiology remains disputed, since around 20%-50% of PCOS women do not display hyperandrogenemia. The microenvironment of the ovary critically influences follicular development. In the present study, we assessed the role of androgen in PCOS by investigating whether excessive follicular fluid androgen was present in PCOS patients with normal serum androgen levels and influenced by follicular fluid insulin resistance（IR）.Follicular fluid samples of 105 women with PCOS and 105 controls were collected. Levels of steroid hormones,glucose and insulin in the follicular fluid were examined and compared with data from serum biochemistry tests. We found that 64.9%（63/97） of PCOS patients with normal serum androgen levels displayed abnormally high follicular fluid androgen level. The follicular fluid androgen level was positively correlated with follicular fluid IR within a certain range and follicular fluid estrogen-to-testosterone（E2/T） ratio was significantly reduced in these patients.These results indicated that there existed a subgroup of PCOS patients who displayed excessive follicular fluid androgen and IR despite their normal circulating testosterone（T） levels. Our study highlights the importance of ovary hyperandrogenism and IR in the etiology of PCOS.

SWM-DE:Statistical wavelet model for joint denoising and enhancement for multimodal medical images

Medical images are usually degraded by numerous noises during acquisition or transmission,which often causes low contrast leading to deterioration of image quality.As such,medical image denoising and enhancement has become a paramount routine task.To overcome this problem,we propose a cutting-edge joint statistical and morphological model for the denoising and enhancement operation.Firstly,we propose a statistical model in formulating the marginal distribution of the wavelet coefficients.This model is integrated into a Bayesian inference framework to develop a maximum a posterior(MAP)estimator of the noise-free coefficient.Based on the statistical model,we eliminate the need for noise level estimation,and allows the model to automatically adapts to the observed image data.Secondly,we propose an adjustable morphological reconstruction model to eliminate known and unknown noises associated with medical images,while preserving the image details.After these operations,the image is decomposed into several wavelet subbands to extract the illumination and detail components.The image is then reconstructed based on the inverse wavelet to generate the enhanced noise-free image.Experimental results show that the proposed framework obtained high EME values of 41.04,48.81,47.81,and 45.75 for OCTA,FFA,CT,and X-ray imaging modalities,and performs better than the state-of-the-art methods.The proposed algorithm can effectively and efficiently enhance medical images,which will assist the clinicians in disease diagnosis,monitoring,and treatment.

土著昆虫素毒蛾在本地植物芦苇与入侵植物互花米草上的生活史

互花米草(Spartina alterniflora)入侵盐沼生态系统导致了土著广食性昆虫素毒蛾(Laelia coenosa)发生宿主转移。但是,目前对素毒蛾在互花米草和芦苇(Phragmites australis)上的生活史规律的比较尚未见报道,而此信息对评价素毒蛾能否持续利用互花米草具有重要的参考价值。为了明确素毒蛾在其原始宿主芦苇和外来新宿主互花米草上的生活史动态,我们在上海崇明长江口盐沼湿地中,对素毒蛾在芦苇和互花米草生境中的发生情况进行了系统调查。结果显示,虽然素毒蛾在芦苇和互花米草上均一年发生3代,并都以幼虫越冬,但在互花米草生境中,越冬代幼虫开始越冬的时间要比芦苇中晚20d左右,其他世代中的多个虫态在互花米草上持续出现的时间也比芦苇上延迟了约10 d。这些结果表明,互花米草入侵后素毒蛾在外来植物上出现的持续时间虽然发生了延长,但其年世代数未变化。我们推测素毒蛾在互花米草和芦苇上生长发育规律的差异可能受生境的资源可利用性及两种植物的营养与防御水平调控。

高精度轻量级的人脸关键点检测算法

针对当前人脸关键点检测算法网络模型复杂度高、在计算资源受限时不利于部署的问题,基于知识蒸馏思想,提出了一种高精度、轻量级的人脸关键点检测算法。通过改进残差网络(ResNet50)中的Bottleneck模块并引入分组反卷积,得到轻量级的学生网络。同时提出逐像素损失函数和逐像素对损失函数,通过对齐教师网络与学生网络的输出特征图与中间特征图,将教师网络的先验知识迁移至学生网络,从而提高学生网络的检测精度。实验结果表明,本算法得到的学生网络参数量为2.81M,模型大小为10.20MB,在GTX1080显卡上的每秒传输帧数为162frame,在300W和WFLW数据集上的平均误差分别为3.60%和5.50%。