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With the advent of the 5G epoch and the gradual development of information technology, people need broader transmission bandwidth. However, the current devices which can compensate for optical fiber transmission loss, such as the rare-earth-doped fiber amplifiers, can compensate for transmission losses for a narrow range of wavelengths, which cannot satisfy people’s needs. Therefore, this paper will further study the gain of 1865nm Thulium-doped fiber amplifier. The Matlab program is used in this experiment to carry out the numerical simulation. Using the numerical simulation method, this article analyzed the gain, pump power, signal power, and amplified spontaneous emission as functions of fiber length. This paper also verified the influence of the overlap factor on the gain of the Thulium-doped fiber amplifier. This experiment can provide a reference for length-choosing of the Thulium-doped fiber amplifier for a maximum gain.

Deposition particles can lead to blockage, odor, and corrosion of pipes, and the deposition process of suspended particles is particularly complicated. In order to quantify the deposition process of suspended particles and mastered the critical conditions for the deposition in storm drainage, the process was simulated experimentally, and the deposition states of suspended particles under the different roughness of pipe wall, particle size, and density were analyzed. Two mathematical models of deposition critical velocity and easy deposition velocity were established. Results showed that with the increase of particle size and density, the gravity of particles increased and deposition was more likely to occur. In the rough pipeline, the kinetic energy consumption of water flow increased, the ability to carry particles was weakened, and the deposition rate would increase accordingly. The higher the flow velocity, the lower the deposition rate. The deposition states of particles in the pipeline could be divided into three types according to the deposition rates: "no deposition," "minor deposition," and "bulk deposition." Verification showed that the difference rates between the calculated values and measured values of the deposition critical velocity ranged from - 3.23 to 2.86%, and the difference rates of the easy deposition velocity were - 4.14-4.72%, showing good consistency.

Background: Breast cancer is one cancer that develops from breast tissue and one of the major reasons for the death of women all over the world. The tumor infiltrating lymphocytes in tumor immune microenvironment are correlated with the prognosis in breast cancer patients, and play an important role in the occurrence and development of breast cancer. Method: In this study, by integrated the immune gene expression of 20 breast cancer cohorts from the public dataset, an immune-based prognostic score was established. This immune-based prognostic score was found to be correlated with prognosis, stromal score, tumor purity, three famous immune checkpoints, and immune escape mechanism in breast cancer patients. Results: The clinical application of the prognostic score was verified by the breast cancer patients treated with chemotherapy, and good therapeutic benefit of the prognostic score was obtained. In addition, the XGBoost classifier was used to construct for predicting the high and low prognostic score subtypes, and the predictive results indicated that the XGBoost was suitable to predict these two subtypes in breast cancer patients. Conclusion: Based on these results, we believed that the prognostic score may be used as an effective prognostic marker and may provide great help for chemotherapy treatment of breast cancer patients

The expression and activity of transcription factors, which directly mediate gene transcription, are strictly regulated to control numerous normal cellular processes. In cancer, transcription factor activity is often dysregulated, resulting in abnormal expression of genes related to tumorigenesis and development. The carcinogenicity of transcription factors can be reduced through targeted therapy. However, most studies on the pathogenic and drug-resistant mechanisms of ovarian cancer have focused on the expression and signaling pathways of individual transcription factors. To improve the prognosis and treatment of patients with ovarian cancer, multiple transcription factors should be evaluated simultaneously to determine the effects of their protein activity on drug therapies. In this study, the transcription factor activity of ovarian cancer samples was inferred from virtual inference of protein activity by enriched regulon algorithm using mRNA expression data. Patients were clustered according to their transcription factor protein activities to investigate the association of transcription factor activities of different subtypes with prognosis and drug sensitivity for filtering subtype-specific drugs. Meanwhile, master regulator analysis was utilized to identify master regulators of differential protein activity between clustering subtypes, thereby identifying transcription factors associated with prognosis and assessing their potential as therapeutic targets. Master regulator risk scores were then constructed for guiding patients’ clinical treatment, providing new insights into the treatment of ovarian cancer at the level of transcriptional regulation.

Breast cancer is a kind of malignant tumor that occurs in breast tissue, which is the most common cancer in women. Cellular metabolism is a critical determinant of the viability and function of cancer cells in tumor microenvironment. In this study, based on the gene expression profile of metabolism-related genes, the prognostic value of 20 metabolic pathways in patients with breast cancer was identified. A universal risk stratification signature that relies on 20 metabolic pathways was established and validated in training cohort, two testing cohorts and The Cancer Genome Atlas pan cancer cohort. Then, the relationship between metabolic risk score subtype, prognosis, immune infiltration level, cancer genotypes and their impact on therapeutic benefit were characterized. Results demonstrated that the patients with the low metabolic risk score subtype displayed good prognosis, high level of immune infiltration and exhibited a favorable response to neoadjuvant chemotherapy and immunotherapy. Taken together, the work presented in this study may deepen the understanding of metabolic hallmarks of breast cancer, and may provide some valuable information for personalized therapies in patients with breast cancer.

Microorganisms transform nitrogen and phosphorus in the sediment of sewage pipelines. When the sediment was scoured by water flow, these elements migrate. This work studied the changes in biofilm morphology and microbial community structure, and focused on the differences in the transformation of nitrogen and phosphorus along the pipeline. The results showed that the nitrogen and phosphorus concentrations varied systematically with time and space (the front, middle, and posterior segments of the pipe). With time, amino acid nitrogen (AAN) concentration in the sediment gradually decreased, NH

Triple-negative breast cancer (TNBC) is the breast cancer subtype with the highest fatality rate, and it seriously threatens women’s health. Recent studies found that the level of immune cell infiltration in TNBC was associated with tumor progression and prognosis. However, due to practical constraints, most of these TNBC immune infiltration studies only used a small number of patient samples and a few immune cell types. Therefore, it is necessary to integrate more TNBC patient samples and immune cell types to comprehensively study immune infiltration in TNBC to contribute to the prognosis and treatment of patients. In this study, 12 TNBC datasets were integrated and an extensive collection of 182 gene sets with immune-related signatures were included to comprehensively investigate tumor immune microenvironment of TNBC. A single sample gene set enrichment analysis was performed to calculate the infiltration score of each immune-related signature in each patient, and an immune-related risk scoring model for TNBC was constructed to accurately assess patient prognosis. Significant differences were found in immunogenomic landscape between different immune risk subtypes. In addition, the immunotherapy response and chemotherapy drug sensitivity of patients with different immune risk subtypes were also analyzed. The results showed that there were significant differences in these characteristics. Finally, a prediction model for immune risk subtypes of TNBC patients was constructed to accurately predict patients with unknown subtypes. Based on the aforementioned findings, we believed that the immune-related risk score constructed in this study can assist in providing personalized medicine to TNBC patients.

Transcription factors directly bind to DNA and regulate the expression of the gene, causing epigenetic modification of the DNA. They often mediate epigenetic parameters of transcriptional and posttranscriptional mechanisms, and their expression activities can be used to characterize genomic aberrations in cancer cell. In this study, the activity profile of transcription factors inferred by VIPER algorithm. The autoencoder model was applied for compressing the transcription factor activity profile for obtaining more useful transformed features for stratifying patients into two different breast cancer subtypes. The deep learning-based subtypes exhibited superior prognostic value and yielded better risk-stratification than the transcription factor activity-based method. Importantly, according to transformed features, a deep neural network was constructed to predict the subtypes, and achieved the accuracy of 94.98% and area under the ROC curve of 0.9663, respectively. The proposed subtypes were found to be significantly associated with immune infiltration, tumor immunogenicity and so on. Furthermore, the ceRNA network was constructed for the breast cancer subtypes. Besides, 11 master regulators were found to be associated with patients in cluster 1. Given the robustness performance of our deep learning model over multiple breast cancer cohorts, we expected this model may be useful in the area of prognosis prediction and lead some possibility for personalized medicine in breast cancer patients.

During rainfall, phosphorus in drainage pipe sediments is easily washed and released. This study investigates the migration of phosphorus between sediments and water in storm and sewage sewers, the microbial community structure in sediments, and phosphorus transformation under biological action. Results showed that when the initial concentration of phosphorus in stormwater (water column) in storm sewer was high (1-2 mg/L), the total phosphorus (TP) level decreased in the water column but increased in the sediments, showing a trend of phosphorus migration from the water column to the sediments. Moreover, under high concentration (2 mg/L), the TP level decreased by 83.19% in the water column within 210 min, which was greater than 64.9% of the medium-concentration stormwater (1 mg/L). In sewage sewer, when the initial concentration of phosphorus in sewage was about 2 mg/L, phosphorus would migrate from the sediments and interstitial water to the water column because of the high concentration of phosphorus in the sediments. In addition, the variation in phosphorus was caused not only by concentration gradient but also by microbial communities. Phosphate accumulating organisms, such as Alphaproteobacteria, Gammaproteobacteria, and Actinobacteria, existed in the storm and sewage sewers, which could ingest dissolved reactive phosphorus in the water column and interstitial water and convert it into phosphorus in organisms. In storm sewers, Acidimicrobiia transferred phosphorus from the water column and interstitial water to the sediments through biochemical reactions and physical adsorption. In sewage sewers, organic acids secreted by Clostridia, Bacteroidia, and Bacilli could dissolve some insoluble phosphorus in sediments and then transfer them to interstitial water.

The rice-crayfish field (i.e., RCF), a newly emerging rice cultivation pattern, has greatly expanded in China in the last decade due to its significant ecological and economic benefits. The spatial distribution of RCFs is an important dataset for crop planting pattern adjustment, water resource management and yield estimation. Here, an object- and topology-based analysis (OTBA) method, which considers spectral-spatial features and the topological relationship between paddy fields and their enclosed ditches, was proposed to identify RCFs. First, we employed an object-based method to extract crayfish breeding ditches using very high-resolution images. Subsequently, the paddy fields that provide fodder for crayfish were identified according to the topological relationship between the paddy field and circumjacent crayfish ditch. The extracted ditch objects together with those paddy fields were merged to derive the final RCFs. The performance of the OTBA method was carefully evaluated using the RCF and non-RCF samples. Moreover, the effects of different spatial resolutions, spectral bands and temporal information on RCF identification were comprehensively investigated. Our results suggest the OTBA method performed well in extracting RCFs, with an overall accuracy of 91.77%. Although the mapping accuracies decreased as the image spatial resolution decreased, satisfactory RCF mapping results (>80%) can be achieved at spatial resolutions greater than 2 m. Additionally, we demonstrated that the mapping accuracy can be improved by more than 10% when near-infrared (NIR) band information was involved, indicating the necessity of the NIR band when selecting images to derive reliable RCF maps. Furthermore, the images acquired in the rice growth phase are recommended to maximize the differences of spectral characteristics between paddy fields and ditches. These promising findings suggest that the OTBA approach performs well for mapping RCFs in areas with fragmented agricultural landscapes, which provides fundamental information for further agricultural land use and water resources management.

A novel poly(acrylic acid-co-acrylamide)/halloysite nanotubes [PAA-AM/HNTs] superabsorbent composite was synthesized by free radical polymerization with using HNTs as an inorganic additive. The composite was characterized by Fourier transform infrared spectroscopy, scanning electron microscope, and thermogravimetric analysis. The results revealed that HNTs and PAA-AM were combined well together to form a porous structure with a pore size of about 10 μm, and HNTs were uniformly distributed in the composite. The thermal stability was improved by adding HNTs in the composite. The influences of contents of initiator and halloysite, neutralization degree of AA, and molar ratio of AM to AA on water absorbency were investigated. The water absorbency and the water retention capacity were improved after adding HNTs into PAA-AM. The composite containing 10% HNTs had the highest water absorbency of 1276 g/g in distilled water. Moreover, PAA-AM/HNTs composite also had a high swelling rate within 60 min and could maintain 78% initial swelling capability after five reswelled test. The substantial enhancement of swelling properties enables PAA-AM/HNTs suitable for numerous practical applications. POLYM. COMPOS., 36:229–236, 2015. © 2014 Society of Plastics Engineers

A 2-D dynamic model was proposed to describe the dynamic behavior of the ramp/lift-tab interface of a one-inch hard disk drive with consideration of the air bearing force and contact stages during the unloading process. The contribution of the geometric parameters of the ramp/lift-tab interface on the dynamic performance of the suspension lift-tab was studied through simulation. A modified Reynolds equation and an iterative formulation for numerical scheme were presented considering continuum Poiseuille flows. The dynamic model developed for the lift-tab motion was extended to simulate the contact and separation stages of head-disk interface. The contact forces and deformation at the ramp/lift-tab contact interface were calculated. The effect of the horizontal velocity of the suspension lift-tab on the dynamic performance of the slider was analyzed. The results show that the dynamic characteristics of slider were independent on the geometric parameters of the ramp and the velocity of the suspension lift-tab. The calculation method to solve the Reynolds Equation proposed in the paper is with enough precision and high efficiency.

The dynamic characteristics of the head disk interface of hard disk drives were simulated by using finite element method. The linear and angular displacement response of the suspension slider and disk were obtained and analyzed. The effect of the amplitude and duration of the external shock on the response of the slider and disk were discussed. The results can be used for the further study of operational shock response of a disk-suspension-slider air bearing system.

The dynamic characteristics of head/disk interface and lift-tab/ramp interface in hard disk drives subject to an external shock were modeled. The displacement responses to the half sinusoidal impulse with different duration and acceleration amplitude were simulated. The dynamic behavior of dual sliders at the interface was analyzed based on the shock response of sliders and the contact at the head/disk interface and the contact between the components of suspension assembly. The results can be beneficial to further application of load/unload technology.

The dynamics of the head/disk interface and the lift-tab ramp interface of hard disk drive subject to an external shock during load/unload process were modeled and simulated. The effects of the shock duration and amplitude of shock impulse on the dynamic and contact characteristics of related interfaces were analyzed. The results show that the effects of the shock on contact force and displacement response of dual sliders are different. The influence of the impact on the upper slider is greater than the lower one. These results are beneficial to the improvement of the head/disk interface and further application of the load/unload technology.

The Dynamic characteristics of ultra-thin gas film at the head/disk interface of hard disk drives were studied numerically. The modified Reynolds equation for the description of the dynamic behavior of gas flow was solved by using an approach based on PDE module and iteration method. Two kinds of typical slider profiles were used to testify the proposed numerical methods. The simulation results show that the rail profile and the flying height of the slider have great impact on the dynamic characteristics of the slider of hard disk drives.