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U-Net and its variants have showcased exceptional performance in the domain of breast medical image segmentation. By employing a fully convolutional network (FCN) structure for semantic segmentation, the symmetrical structure of U-Net offers remarkable flexibility and adaptability. It can be tailored to diverse image segmentation tasks and challenges by adjusting network depth and incorporating new modules, leaving a significant impact on subsequent network designs. This paper aims to delve into the application of U-shaped convolutional networks in breast medical image segmentation, categorizing and summarizing U-shaped convolutional networks used for this purpose in recent years. It outlines the widely used breast medical image datasets and evaluation metrics, discusses common data augmentation techniques, and provides a detailed introduction to the network structure of the U-Net model along with traditional segmentation methods for breast medical images. Furthermore, it summarizes the improvements made to the U-Net network structure for breast medical image segmentation, including modifications like residual structures, multi-scale features, dilation mechanisms, attention mechanisms, skip connection mechanisms, and integration with Transformers. Finally, it addresses the current challenges and problems encountered in breast medical image segmentation and offers insights into future research directions.

Fault-fracture bodies are developed in the southwestern margin of Ordos Basin， and thus， the study on the controlling effect of fracture bodies on sweet spot distribution of Yanchang Formation reservoirs needs to be deepened. In this paper， based on the extensive seismic and logging interpretation results， the characteristics of fault-fracture bodies are described from the point of view of their evolution mechanism， and then the controlling effect of fault-fracture bodies on oil and gas is systematically discussed. The results show that vertical strike-slip faults are developed in the southwest margin of Ordos Basin， with Y-shaped， flower-like， and negative flower-like structures. The faults usually pass through the bottom of Chang 7 Member， the bottom of Yan’an Formation， the bottom of the Cretaceous series， and the basement. Some of the faults retain the early reverse fault properties， indicating that the late inversion degree is not complete. The main fault has different shapes and migrations in different parts， and the section shows the cyclic transformation of tension-torsion and compression-torsion properties. On the plane， different types of fracture combinations appear alternately. The development model of strike-slip faults is established， and the strike-slip faults have typical characteristics of “multi-stage activity and inherited development”. Chang 8 Member mainly develops vertical fractures and horizontal bedding fractures. The development frequency of horizontal bedding fractures is 62.5%， while that of vertical fractures is 37.5%. The oil level of vertical fractures is relatively higher. Fractures are mainly developed in fine sandstone in distributary channels. When the distance from the main fault is greater than 1.25-1.5 km， the degree of fracture development decreases sharply， showing a fault-fracture body boundary. In addition， fractures are relatively developed in the single sand body within 6 m from the main fault. When the thickness of the single sand body exceeds 6 m， the degree of fracture development decreases sharply. The study shows that the index system based on sedimentation （foundation）， structure （dominant）， and fracture （effective） can effectively predict the favorable zones of Chang 8 fault-fracture body reservoir.

The interlaced underwater distributary channel sand bodies are developed in Chang 4+5 reservoir group in Jiyuan area， and their internal contact relationships are complex， which seriously affects the reservoir distribution law and water flooding development effect in this area. It is beneficial to the sustained and stable production and efficient development of Chang 4+5 reservoir in Jiyuan area by the fine study of identification and division of single sand body interface， analyzing the contact modes of sand bodes and their influence on water flooding effect in Chang 4+5 reservoir. Based on the identification and division of the single sand body interface， the core， logging， and dynamic production data are comprehensively applied to delineate the internal contact relationships of sand bodies， and then clarify the influence of transverse cross and vertical superposition relationships of sand bodies on water flooding effect. The results show that there are three vertical superposition relationships of sand bodies in Chang 4+5 reservoir in Jiyuan area， namely cut-stacked， superimposed， and separated. Among them， the cut-stacked sand bodies are more homogeneous， with high oil content and percentage of producing reserves under water flooding， followed by the superimposed sand body. The lateral contact modes of single sand bodies can be divided into three types： isolated mode， docking mode， and side-cut mode. Different contact modes reflect the difference in interwell connectivity of channel sand bodies， which in turn affects the effective time of water injection in oil wells. The effective time of water injection in oil wells corresponding to the side cut mode is short， followed by the docking mode， and the effect of water injection in oil wells corresponding to the isolated sand body is not obvious.

To understand the mechanisms of agricultural ecosystem structure and function in response to soil water deficit under future elevated atmospheric CO2 concentration, we examined the effects of soil water deficit and elevated CO2 concentration ([CO2]) on the stomatal traits, leaf photosynthesis, water use efficiency as well as Rubisco activity and gene expression of winter wheat with environmental growth chambers, whereby the [CO2] was controlled accurately with CO2 sensors. Our results showed that water deficit significantly decreased the plant biomass and net photosynthesis rates (Pn) of winter wheat by 33% and 29%, whereas elevated [CO2] partially mitigated the negative effects of water deficit on plant growth and physiological processes of winter wheat. Meanwhile, water deficit also reduced the stomatal width and regularity of stomatal distribution pattern on winter wheat leaves, but higher [CO2] could optimize the leaf gas exchange efficiency with more regular distribution pattern of stomata. Moreover, elevated [CO2] not only enhanced the Pn of winter wheat plants under water deficit, but also substantially reduced the transpiration rates (Tr) by 25%, and thus elevated [CO2] increased the water use efficiency by 61% when winter wheat plants subjected to water deficit. In addition, elevated [CO2] boosted the initial activity and activation state of Rubisco as well as soluble protein content by 66%, 38%, and 15%, and meanwhile significantly enhanced the gene expression levels of RbcL3 and RbcS2 by 453% and 417%, respectively. These results suggested that elevated [CO2] may optimize leaf gas exchange through modifying stomatal traits as well as the activity and gene express of Rubisco, and thus increased plant biomass, Pn, and water use efficiency to efficiently alleviate the physiological stress of water deficit on growth and development processes of winter wheat. Our findings may not only provide data for further understanding the impacts of water deficit on grain yield and water use efficiency of winter wheat under elevated [CO2], but also have important significance for adaptation management of agricultural ecosystems under global change. [ABSTRACT FROM AUTHOR]

A differential equivalent medium theory method and Biot consistent theory method were applied to an inversion on the pore aspect ratio and crack density of No. 3 primary structure seam and overlaying coal measure strata in Shanxi Group of Guxian well block in Qinshui Basin. The results showed that No. 3 primary structure seam was mainly close spherical pore space system. In the overlaying mud-stone, there was a pore and crack type multi pore space system. With the crack density increased, the crack and pore degree of the coal measure strata would steadily be a maximum in tendency and meanwhile, the rock volume modulus would be reduced obviously and the crack density inversion results would have a certain reference value to guide the exploration of the coal measure gas. [ABSTRACT FROM AUTHOR]

Establishing the remote sensing yield estimation model of wheat-maize rotation cultivated land can timely and accurately estimate the comprehensive grain yield. Taking the winter wheat-summer maize rotation cultivated land in Caoxian County, Shandong Province, as test object, using the Sentinel-2 images from 2018 to 2019, we compared the time-series feature classification based on QGIS platform and support vector machine algorithm to select the best method and extract sowing area of wheat-maize rotation cultivated land. Based on the correlation between wheat and maize vegetation index and the statistical yield, we screened the sensitive vegetation indices and their growth period, and obtained the vegetation index integral value of the sensitive spectral period by using the Newton-trapezoid integration method. We constructed the multiple linear regression and three machine learning (random forest, RF; neural network model, BP; support vector machine model, SVM) models based on the integral value combination to get the best and and optimized yield estimation model. The results showed that the accuracy rate of extracting wheat and maize sowing area based on time-series features using QGIS platform reached 94.6%, with the overall accuracy and Kappa coefficient were 5.9% and 0.12 higher than those of the support vector machine algorithm, respectively. The remote sensing yield estimation in sensitive spectral period was better than that in single growth period. The normalized differential vegetation index and ratio vegetation index integral group of wheat and enhanced vegetation index and structure intensify pigment vegetable index integral group of maize could more effectively aggregate spectral information. The optimal combination of vegetation index integral was difference, and the fitting accuracy of machine learning algorithm was higher than that of empirical statistical model. The optimal yield estimation model was the difference value group-random forest (DVG-RF) model of machine learning algorithm ( R 2 =0.843, root mean square error=2.822 kg·hm -2 ), with a yield estimation accuracy of 93.4%. We explored the use of QGIS platform to extract the sowing area, and carried out a systematical case study on grain yield estimation method of wheat-maize rotation cultivated land. The established multi-vegetation index integral combination model was effective and feasible, which could improve accuracy and efficiency of yield estimation.

Objective: To improve the diagnostic yield of prostate biopsy, which we can achieve by puncture more sites and number of cores, another way to obtain more tissue is to take longer tissue strips. In this study, we evaluated the effect of strip length on cancer diagnosis by needle biopsy and derived a cutoff value of strip length to improve cancer detection., Methods: The pathological reports of 754 patients with suspected prostate cancer who underwent transperineal prostate biopsy were retrospectively analyzed. The age, serum prostate specific antigen (PSA), prostate volume, Gleason score and tissue strip length were analyzed. The length of the tissue strip was compared between the biopsy positive patients and the biopsy negative patients, and the patients were divided into group A（biopsy positive group）and group B（biopsy negative group）, respectively. Statistical analysis of tissue strip lengths was performed to determine cutoff values for biopsy length quality., Results: A total of 10 556 tissue strips were obtained from 754 patients, and 45.1 % of the patients were pathologically diagnosed as prostate cancer. The median length of the tissue strip was 10.5 (9.5, 12.5) mm, the median age was 69 (64,75) years, the median PSA was 12.4 (8.6, 20.8) μg/L, and the median prostate volume was 44.8 (30.5, 64.4) ml. The median length of tissue strips in group A and group B was 11 (10,13) mm and 10 (9,12) mm, respectively. Receiver operating characteristic (ROC) curve analysis was performed on the length of tissue strips in all cases, and the cutoff value of quality assurance was 11.8mm, the area under curve (AUC) was 0.82, and the cut-off value of quality assurance was 11.8mm. Sensitivity 71.4%, specificity 73.8%(P<0.001)., Conclusions: In transperineal prostate biopsy, the cancer detection rate of tissue strips may increase with length. The results of ROC analysis showed that 11.8 mm was used as the cut-off value for quality assurance.

It is objective needs during utilization and management of regional cultivated land resource to use remote sensing to accurately and efficiently retrieve the status of cultivated land fertility at county level and realize the gradation of cultivated land rapidly. In this study, with Dongping County as a case, using Landsat TM satellite imagery and cultivated land fertility evaluation data, the moisture vegetation fertility index (MVFI) was constructed based on surface water capacity index (SWCI) and normalized difference vegetation index (NDVI), and then the optimal inversion model was optimized to obtain the best inversion model, which was further applied and verified at the county scale. The results showed that the correlation coefficient between MVFI and integrated fertility index (IFI) was -0.753, which could comprehensively reflect the growth of winter wheat, soil moisture and land fertility, and had clear biophysical significance. The best inversion model was the quadratic model, with high inversion accuracy. This model was suitable for the inversion of cultivated land fertility in the county. The spatial distribution and uniformity of the inversion results were similar to the results of soil fertility evaluation. The area differences between the high, medium and low grades were all less than 2.9%. This study provided a remote sensing inversion method of cultivated land fertility based on the feature space theory, which could effectively improve the evaluation efficiency and prediction accuracy of cultivated land fertility at the county scale.

A method was developed for the determination of 42 glucocorticoids in infant eczema products by auto-solid phase extraction-high performance liquid chromatography-tandem mass spectrometry (ASPE-UHPLC-MS/MS).The analytes were extracted by acetonitrile after dispersing in saturated sodium chloride solution.Macromolecules matrix were precipitated by adding potassium and zinc acetate, and then purified by HLB SPE column.The chromatographic separations were performed on a DIKMA Endeavorsil TM C18 column (100 mm×2.1 mm, 1.7 μm).Acetonitrile and 0.1%(v/v) formic acid aqueous solution were used as the mobile phases.Electrospray ionization (ESI) source was operated in the positive mode using multiple reaction monitoring (MRM) scanning mode.The results were quantified by external standard method.The correlation coefficients of linear calibration curves were greater than 0.998 in the corresponding mass concentration ranges.The average recoveries at three spiked levels ranged from 78.7% to 101.5%, and the relative standard deviations (RSDs) were 2.0%-8.8%( n =6).The LODs ( S/N ≥ 3) and LOQs were 0.002-0.031 mg/kg and 0.0007-0.103 mg/kg, respectively.The method is simple, rapid, sensitive, and reliable, and can be used for the detection of glucocorticoids in infant eczema products.