Type IIs restriction based combinatory modulation technique for metabolic pathway optimization

Additional file 1: Table S1. Oligonucleotides used in this study

Online Training Through Time for Spiking Neural Networks

Spiking neural networks (SNNs) are promising brain-inspired energy-efficient models. Recent progress in training methods has enabled successful deep SNNs on large-scale tasks with low latency. Particularly, backpropagation through time (BPTT) with surrogate gradients (SG) is popularly used to achieve high performance in a very small number of time steps. However, it is at the cost of large memory consumption for training, lack of theoretical clarity for optimization, and inconsistency with the online property of biological learning and rules on neuromorphic hardware. Other works connect spike representations of SNNs with equivalent artificial neural network formulation and train SNNs by gradients from equivalent mappings to ensure descent directions. But they fail to achieve low latency and are also not online. In this work, we propose online training through time (OTTT) for SNNs, which is derived from BPTT to enable forward-in-time learning by tracking presynaptic activities and leveraging instantaneous loss and gradients. Meanwhile, we theoretically analyze and prove that gradients of OTTT can provide a similar descent direction for optimization as gradients based on spike representations under both feedforward and recurrent conditions. OTTT only requires constant training memory costs agnostic to time steps, avoiding the significant memory costs of BPTT for GPU training. Furthermore, the update rule of OTTT is in the form of three-factor Hebbian learning, which could pave a path for online on-chip learning. With OTTT, it is the first time that two mainstream supervised SNN training methods, BPTT with SG and spike representation-based training, are connected, and meanwhile in a biologically plausible form. Experiments on CIFAR-10, CIFAR-100, ImageNet, and CIFAR10-DVS demonstrate the superior performance of our method on large-scale static and neuromorphic datasets in small time steps.Comment: Accepted by NeurIPS 202

Study on micro-mechanism of the affordable housing community in urban renewal the case of Zunyi city, Guizhou province

Introduction: Affordable housing in China refers to housing with social security for low and middle income people under the unified planning and coordination of the government. In the process of urbanization, the construction of affordable housing and commercial housing should be developed in parallel, but under the role of the real estate market economy, the development of the two is unbalanced, resulting in a disparity in quantity, a large gap in quality, unreasonable management, and even residential segregation. The construction and development of China's affordable housing community is a huge and complex systemic project. This study focuses on a series of problems in the relationship between supply and demand of affordable housing based only on the development context of urban renewal at this stage.Methods: Based on existing literature and official data, combined with field visits and research, this study uses Vensim PLE software to build a system model for converting various types of stock into affordable housing, and to investigate the effect of various policies on solving the problem of supply and demand of affordable housing.Results: The research results show that 1) the policies stimulate the increase of urban population and help promote the supply cycle of affordable housing; 2) under the stimulation of the supply policy of converting stock housing into affordable housing, social investment will improve by 33%–64% and the gap of affordable housing will decrease by 29%–58%; 3) under the stimulation of the policy of optimizing the management of affordable housing, the coverage rate of affordable population will improve by 3%–5% and the middle and low income households’ per capita housing floor area will increase by 9%–18% l; 4) under the comprehensive influence of the combined policies, the urban population will grow healthily, the per capita income and per capita housing floor area of low- and middle- income people will be improved, the stock of housing will be reduced, the number of affordable housing will increase, the affordable housing gap will be reduced, and the affordable housing community will be developed sustainably and healthily.Meaning: The research results and recommendations will provide references for the government and competent authorities to enact or update the policies on affordable housing

Synergetic effect on methylene blue adsorption to biochar with gentian violet in dyeing and printing wastewater under competitive adsorption mechanism

Decolorization of dyeing/printing wastewater by carbon-based materials has been carried out to study the adsorption of dye molecules onto adsorbent. Biomass-derived activated carbon (SAC) was sampled from cornstalk pyrolysis in the presence of K2CO3 as an activator. Adsorption of methylene blue (MB) and gentian violet (GV) onto SAC was examined to probe the mechanisms, isotherms, and kinetics of dye removal in single- or two-component systems. According to the adsorption rate in a single-component system, three stages were identified. The equilibrium adsorption capacity for MB onto SAC in the single-component system is 274.84 mg g−1 which is higher than that for GV of 266.57, meanwhile the pseudo-second-order (PSO) model would describe the adsorption kinetics with the correlation coefficient higher than 0.99. In the binary GV-MB system, presence of GV promoted MB adsorption to 325.15 mg g−1 and 287.73 mg g−1 at different GV concentrations while the PSO model was also applicable. Furthermore, differences between experimental and calculated values by the Freundlich and Langmuir isotherms indicated the occurrence of competitive adsorption in the two-component system. The gained insights are beneficial for removing the multiple dyes from industrial wastewater, economically and effectively and thus paving the way to the establishment of a greener society

Prognostic Role of High Stathmin 1 Expression in Patients with Solid Tumors: Evidence from a Meta-Analysis

Background/Aims: Several recent studies have demonstrated that Stathmin 1expression may be closely associated with prognosis in patients with various types of cancers. In the present study, we conducted a meta-analysis of all available studies in the English literature to assess the prognostic value of Stathmin 1expression in patients with solid cancers. Methods: The online databases PubMed, Embase, and Web of Science were searched for literature regarding Stathmin 1 and its association with patient outcomes associated with solid cancers. Results: A total of 23 articles including 26 studies that contained 5 335 patients were retrieved and analyzed. Our results indicated that high Stathmin 1 expression yielded a worse overall survival (OS) (hazard ratio [HR] = 2.17, 95% confidence interval [CI]: 1.81–2.60), disease-free survival (DFS) (HR = 2.46, 95% CI: 2.00–3.02), disease-specific survival (DSS) (HR = 1.98, 95% CI: 1.58– 2.47) and progression-free survival (PFS)/recurrence-free survival (RFS) (HR = 2.09, 95% CI: 1.51–2.89). Furthermore, the association of high Stathmin 1 expression with poor survival was significant even for sub-group analyses of different tumor types, ethnicities, methods used to calculate HRs, detected methods, and analysis types. Conclusion: In summary, this meta-analysis determined that high Stathmin 1 expression is associated with poor prognosis in patients with solid cancers and expression of this protein could be a clinically useful prognostic biomarker

Exploring the Social Meaning of Curing HIV: A Qualitative Study of People Who Inject Drugs in Guangzhou, China

Our objective was to explore the social meaning of HIV and perceptions of an HIV cure among people who inject drugs (PWID) in Guangzhou, China, which speaks to ethical and resource challenges to development in this field. We conducted a qualitative research study using in-depth interviews. We analyzed interview transcripts from 29 PWID, eight physicians, and three social workers from an outpatient HIV clinic and two methadone maintenance treatment centers. The social meaning of HIV infection and perceptions of an HIV cure reflected patients' relationships with society, health systems, and physicians. First, HIV infection decreased perceived social worth and disrupted peer relationships. The possibility of being cured renewed patient hope for regaining physical well-being and achieving social mobility. However, the existence of a cure may not alter the HIV-related stigma due to its association with stigmatized behaviors and marginalized groups. Second, although stigma was a significant barrier to engagement in health care, hope for a cure may outweigh fears of stigma and enhance linkage to HIV testing and treatment as well as methadone services. A cure may exacerbate perceived health disparities if inaccessible to key affected populations such as PWID. The social implications of an HIV cure among this key affected population may inform the design and implementation of cure clinical trials. Careful management of patient expectations, focusing research on key affected populations, expanding HIV testing and treatment systems, improving access to harm reduction programs, and ensuring post-trial access are important considerations for HIV cure research

Gene cloning, expression, and characterization of two endo-xylanases from Bacillus velezensis and Streptomyces rochei, and their application in xylooligosaccharide production

Endo-xylanase hydrolyzing xylan in cellulosic residues releasing xylobiose as the major product at neutral pH are desirable in the substitute sweeteners industry. In this study, two endo-xylanases were obtained from Streptomyces rochei and Bacillus velezensis. SrocXyn10 showed the highest identity of 77.22%, with a reported endo-xylanase. The optimum reaction temperature and pH of rSrocXyn10-Ec were pH 7.0 and 60°C, with remarkable stability at 45°C or pHs ranging from 4.5 to 11.0. rBvelXyn11-Ec was most active at pH 6.0 and 50°C, and was stable at 35°C or pH 3.5 to 10.5. Both rSrocXyn10-Ec and rBvelXyn11-Ec showed specific enzyme activities on wheat arabinoxylan (685.83 ± 13.82 and 2809.89 ± 21.26 U/mg, respectively), with no enzyme activity on non-xylan substrates. The Vmax of rSrocXyn10-Ec and rBvelXyn11-Ec were 467.86 U mg−1 and 3067.68 U mg−1, respectively. The determined Km values of rSrocXyn10-Ec and rBvelXyn11-Ec were 3.08 g L−1 and 1.45 g L−1, respectively. The predominant product of the hydrolysis of alkaline extracts from bagasse, corncob, and bamboo by rSrocXyn10-Ec and rBvelXyn11-Ec were xylooligosaccharides. Interestingly, the xylobiose content in hydrolysates by rSrocXyn10-Ec was approximately 80%, which is higher than most reported endo-xylanases. rSrocXyn10-Ec and rBvelXyn11-Ec could be excellent candidates to produce xylooligosaccharides at neutral/near-neutral pHs. rSrocXyn10-Ec also has potential value in the production of xylobiose as a substitute sweetener