Sidestream sludge treatment approaches have been developed in recent years to achieve mainstream nitrite shunt or partial nitritation, where NOB are selectively inactivated by biocidal factors such ...as free nitrous acid (FNA) or free ammonium (FA) in a sidestream reactor. The existence of NOB in raw wastewater has been increasingly realized and could pose critical challenge to stable NOB suppressions in those systems. This study, for the first time, evaluated the impact of influent NOB on the NOB suppressions in a mainstream nitrite shunt system achieved through sidestream sludge treatment. An over 500-day sequential batch reactor operation with six experimental phases rigorously demonstrated the negative effects of influent NOB on mainstream NOB control. Continuously seeding of NOB contained in influent stimulated NOB community shifts, leading to different extents of ineffective NOB suppression. The role of primary wastewater treatment in NOB removal from raw wastewater was also investigated. Results suggest primary settling and High Rate Activated Sludge system could remove a large part of NOB contained in raw wastewater. Primary treatment for raw wastewater is necessary for ensuring stable mainstream NOB suppressions.
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•Influent NOB challenge NOB suppression by stimulating community shift and resistance.•Primary settling substantially reduces NOB in raw wastewater.•High-rate activated sludge treatment substantially reduces NOB in raw wastewater.•This study expanded the current knowledge of mainstream NOB suppression.
The knowledge contribution of members is essential and beneficial to both the business and users of online health communities (OHCs). This study explores and tests the effects of OHC users' ...psychological contracts on their community identification and knowledge-sharing behavior. A total of 367 valid responses from several well-known OHCs in China are used in the data analysis. The results of the path analysis with structural equation modeling show that users' transactional psychological contracts have a negative effect on their knowledge contribution both directly and indirectly by weakening their community identification. In contrast, users' relational psychological contracts can lead to increased active knowledge contributions both directly and indirectly by enhancing their community identification. Knowledge sharing self-efficacy can strengthen the relationship between relational psychological contracts and knowledge contributions, and the relationship between community identification and knowledge contributions. However, it has no significant impact on the path from transactional psychological contracts to knowledge contribution. The implications and direction of future works are presented on the basis of the results of the empirical analysis.
Abstract Background Upper lumbar disc herniation (ULDH) accounts for 1-10% of all lumbar disc herniations (LDH). This study aimed to evaluate the clinical characteristics and outcomes of patients ...with ULDH who underwent percutaneous transforaminal endoscopic discectomy (PTED) compared with those with lower LDH. Methods 60 patients with ULDH or L4–L5 LDH treated with PTED between May 2016 and October 2021. MacNab criteria, visual analog scale (VAS) of back pain and leg pain, and Japanese Orthopedic Association (JOA) were evaluated before and after surgery. Results In the L1–L3 group, 59.1% of the patients had a positive femoral nerve tension test, and 81.8% of the patients had a sensory deficit. Both groups showed significant improvements in VAS scores for low back and leg pain, and JOA scores postoperatively. No significant differences in the degree of improvement were observed between the two groups. The excellent/good rate was 81.8% in the L1–L3 group and 84.2% in the L4–L5 group, showing no significant difference. Conclusion PTED has comparable efficacy in treating ULDH as it does in treating lower LDH, it is a safe and effective treatment method for ULDH.
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Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Image fusion model based on autoencoder network gets more attention because it does not need to design fusion rules manually. However, most autoencoder-based fusion networks use two-stream CNNs with ...the same structure as the encoder, which are unable to extract global features due to the local receptive field of convolutional operations and lack the ability to extract unique features from infrared and visible images. A novel autoencoder-based image fusion network which consist of encoder module, fusion module and decoder module is constructed in this paper. For the encoder module, the CNN and Transformer are combined to capture the local and global feature of the source images simultaneously. In addition, novel contrast and gradient enhancement feature extraction blocks are designed respectively for infrared and visible images to maintain the information specific to each source images. The feature images obtained from encoder module are concatenated by the fusion module and input to the decoder module to obtain the fused image. Experimental results on three datasets show that the proposed network can better preserve both the clear target and detailed information of infrared and visible images respectively, and outperforms some state-of-the-art methods in both subjective and objective evaluation. At the same time, the fused image obtained by our proposed network can acquire the highest mean average precision in the target detection which proves that image fusion is beneficial for downstream tasks.
Target tracking is to predict the state of the current target according to the target context information of video sequence. Deep learning is gradually widely used in the field of target tracking. ...This paper elaborates on the development background of target tracking algorithms and deep learning, and reviews traditional target tracking. Based on different network task functions, target tracking algorithms based deep learning is divided into: deep learning target tracking algorithm based classification, deep learning target tracking algorithm based regression, and target tracking algorithm based on the combination of regression and classification. This paper selects representative target tracking algorithm for experiments, compares the characteristics of different algorithms. Finally, this paper analyzes the problems of current target tracking algorithms based on deep learning, and prospects the future development direction. The experimental results show that deep Siamese tracking networks are superior in accu
•The toxic threshold of FA concentration in P metabolism was 17.76mgNL−1.•Acclimation took place by PAOs for FA concentration of 8.88mgNL−1.•FA deteriorated the settleability, stability and integrity ...of the granules.•FA could repress the excretion of extracellular polysaccharides.•FA inhibition may provide a competitive advantage to GAOs over PAOs.
The inhibition of free ammonia (FA) to the granule-based enhanced biological phosphorus removal (EBPR) system and the recoverability from macro- to micro-scale were investigated in this study. FA was found to seriously deteriorate the EBPR performance and sludge characteristic (settleability and morphology). The FA inhibitory threshold of 17.76mgNL−1 was established. Acclimation phenomenon took place when poly-phosphate accumulating organisms (PAOs) were exposed for long time to constant FA concentration (8.88mgNL−1). The repressed polysaccharides excretion could lead to breaking the stability and integrity of the granules. Therefore, the reduced particle size and granule disintegration were observed. The molecular analysis revealed that FA had a significant influence on the microbial communities and FA inhibition may provide a competitive advantage to glycogen accumulating organisms (GAOs) over PAOs. Interestingly, the community composition was found irreversible by recovery (Dice coefficients, 36.3%), although good EBPR performance was re-achieved.
Study Design
Retrospective cohort study.
Objectives
The main purpose of the present study was to report the incidence and identify predictors of reoperation in patients with lumbar spinal stenosis ...(LSS) treated with percutaneous endoscopic transforaminal decompression (PETD).
Methods
This study retrospectively reviewed consecutive patients with LSS who underwent PETD at our center between January 2016 and July 2020. The incidence of reoperations was calculated. We then designed a surgical period-matched case-control study to identify predictors among demographic data, clinical baseline data, and imaging parameters.
Results
This study identified 496 eligible patients. 33 (6.7%) patients underwent reoperation with a mean follow-up of 3 years, consisting 22 (4.4%) at the index level and 11 (2.2%) at the adjacent levels. There were significant differences in age and age-adjusted Charlson comorbidity index (AACCI) between the two groups, with younger age (P = .004) and lower AACCI (P = .019) in reoperation group. Age was identified as the sole independent predictor (P = .006). The duration of symptoms ≥12 months (P = .034) and the presence of heart problems (P = .012) were recognized as specific predictors among patients younger than 65 years.
Conclusions
In a mean follow-up of 3 years, the incidence of reoperation in LSS treated with PETD was 6.7%. A younger age was the independent predictor for reoperation. Younger patients with the duration of symptoms ≥12 months or without heart problems were more likely to undergo a second operation. Prospective randomized controlled trials are required to confirm these findings.
Stable suppression of nitrite oxidizing bacteria (NOB) is one of the major bottlenecks for achieving mainstream nitrite shunt or partial nitritation/anammox (PN/A). It is increasingly experienced ...that NOB could develop resistance to suppressions over an extended time, leading to failure of nitrite shunt or PN/A. This study reports and demonstrates the first effective strategy to overcome NOB adaptation through alternating sludge treatment with free nitrous acid (FNA) and free ammonia (FA). During over 650 days of reactor operation, NOB adaptation to both FNA and FA was observed, but the adaptation was successfully overcome by deploying the alternate treatment strategy. Microbial community analysis showed Nitrospira and Nitrobacter, the key NOB populations in the reactor, have the ability to adapt to FNA and FA, respectively, but do not adapt to the alternation. Stable nitrite shunt with nitrite accumulation ratio over 95% and excellent nitrogen removal were maintained for the last 10 months with only one alternation applied. N2O emission increased initially as the attainment of nitrite shunt but exhibited a declining trend during the study. By using on-site-produced nitrite and ammonium, the proposed strategy is feasible and sustainable. This study brings the mainstream nitrite shunt and PN/A one step closer to wide applications.
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