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Abstract Aiming at the shortcomings of the BP neural network in practical applications, such as easy to fall into local extremum and slow convergence speed, we optimized the initial weights and thresholds of the BP neural network using the particle swarm optimization (PSO). Additionally, cloud computing service, web technology, cloud database and numerical simulation were integrated to construct an intelligent feedback analysis cloud program for underground engineering safety monitoring based on the PSO-BP algorithm. The program could conveniently, quickly, and intelligently carry out numerical analysis of underground engineering and dynamic feedback analysis of surrounding rock parameters. The program was applied to the cloud inversion analysis of the surrounding rock parameters for the underground powerhouse of the Shuangjiangkou Hydropower Station. The calculated displacement simulated with the back-analyzed parameters matches the measured displacement very well. The posterior variance evaluation shows that the posterior error ratio is 0.045 and the small error probability is 0.999. The evaluation results indicate that the intelligent feedback analysis cloud program has high accuracy and can be applied to engineering practice.

Mobile Edge Computing (MEC) has a widely established merit of bringing powerful computing servers to geographically closer locations to computationally limited devices; hence, reducing the task offloading latency from these devices to the servers. However, the frequent communication between devices and edge servers increases the network-wide traffic, therefore, stands in the way of enjoying notable improvements in network-wide latency. The optimization of this problem becomes of utmost importance to boldly underline the advantages of MEC-based task offloading. Reconfigurable Intelligent Surfaces (RISs) offer the potential to improve wireless transmission environment, thereby contributing to achieving this objective. This paper addresses a network-wide latency optimization problem in the context of multi-RIS-assisted MEC offloading scenarios. This problem is, herein, subdivided into two sub-problems, namely: ${a}$ ) path selection and ${b}$ ) joint optimization of RIS phases and offloading volume. The cascaded channel gain is derived for ${a}$ ). A balanced trade-off is sought between passive beamforming gain and reflection loss by reformulating ${a}$ ) as a shortest path problem using Graph Theory (GT). ${b}$ ) requires a different approach than the typical Successive Convex Approximation (SCA) technique used for single RIS. Instead, a Semi-Definite Relaxation (SDR) method is adopted to transform the non-convex sub-problem into a convex one, solved efficiently using an Alternating Optimization (AO) approach. The results of extensive simulations and numerical analyses reported herein reveal the notable latency reduction potency of multi-RIS-assisted MEC systems by, respectively, 24% as compared to their RIS-agnostic counterparts, and, by 15.34% when compared to systems incorporating a single RIS.

The concrete lining of high-pressure water conveyance tunnels permeates under high-pressure water. Dense and hydrophobic coating can effectively improve the impermeability of concrete. However, the coating exhibits varying impermeability in different high-pressure environments, which can even lead to coating detachment or damage. The objectives of this study are to improve the high-pressure impermeability of concrete by using a polymer coating, and to study the varying impermeability through experiments. This study applied a polymer coating called SCU-SD-SP-II (SSS) to concrete surfaces, and it formed a composite protective layer with an epoxy-modified silicone (EMS) coating. A series of high-pressure impermeability tests were conducted to study the seepage regulation of the coated concrete and the failure mechanism of the SSS coating under cracks in the concrete. The results indicate that the SSS coating has excellent impermeability. Pressurized water of 3 MPa could not permeate the SSS coating with a thickness of 0.5 mm within 24 h. Under both external and internal water pressure conditions, the SSS coatings improved concrete impermeability. Additionally, the average seepage height and relative permeability coefficient of the latter decreased by 49.6% and 71.2%, respectively, compared with the former. After concrete cracking, the SSS coating could withstand 3 MPa pressure on crack surfaces smaller than 1 mm. When the crack width was greater than 2 mm, the SSS coating deformed under 1 MPa pressure. As the pressure increased to 2 MPa or even 3 MPa, the SSS coating was punctured or torn due to stress concentration. This study provides new insights into the impermeability of concrete under high water pressure.

Oxygen is essential to all the aerobic organisms. However, during normal development, disease and homeostasis, organisms are often challenged by hypoxia (oxygen deprivation). Hypoxia-inducible transcription factors (HIFs) are master regulators of hypoxia response and are evolutionarily conserved in metazoans. The homolog of HIF in the genetic model organism C. elegans is HIF-1. In this study, we aimed to understand short-term hypoxia response to identify HIF-1 downstream genes and identify HIF-1 direct targets in C. elegans. The central research questions were: (1) which genes are differentially expressed in response to short-term hypoxia? (2) Which of these changes in gene expression are dependent upon HIF-1 function? (3) Are any of these hif-1-dependent genes essential to survival in hypoxia? (4) Which genes are the direct targets of HIF-1? We combine whole genome gene expression analyses and chromatin immunoprecipitation sequencing (ChIP-seq) experiments to address these questions. In agreement with other published studies, we report that HIF-1-dependent hypoxia-responsive genes are involved in metabolism and stress response. Some HIF-1-dependent hypoxia-responsive genes like efk-1 and phy-2 dramatically impact survival in hypoxic conditions. Genes regulated by HIF-1 and hypoxia overlap with genes responsive to hydrogen sulfide, also overlap with genes regulated by DAF-16. The genomic regions that co-immunoprecipitate with HIF-1 are strongly enriched for genes involved in stress response. Further, some of these potential HIF-1 direct targets are differentially expressed under short-term hypoxia or are differentially regulated by mutations that enhance HIF-1 activity.

Metazoan animals rely on oxygen for survival, but during normal development and homeostasis, animals are often challenged by hypoxia (low oxygen). In metazoans, many of the critical hypoxia responses are mediated by the evolutionarily conserved hypoxia-inducible transcription factors (HIFs). The stability and activity of HIF complexes are strictly regulated. In the model organism C. elegans, HIF-1 stability and activity are negatively regulated by VHL-1, EGL-9, RHY-1 and SWAN-1. Importantly, C. elegans mutants carrying strong loss-of-function mutations in these genes are viable, and this provides opportunities to interrogate the molecular consequences of persistent HIF-1 over-activation. We find that the genome-wide gene expression patterns are compellingly similar in these mutants, supporting models in which RHY-1, VHL-1 and EGL-9 function in common pathway(s) to regulate HIF-1 activity. These studies illuminate the diversified biological roles played by HIF-1, including metabolism and stress response. Genes regulated by persistent HIF-1 over-activation overlap with genes responsive to pathogens, and they overlap with genes regulated by DAF-16. As crucial stress regulators, HIF-1 and DAF-16 converge on key stress-responsive genes and function synergistically to enable hypoxia survival.

The ultra-short base line (USBL) is a widely used technique in achieving the underwater acoustic localization (UWAL). Aimed at increasing the localization precision, we propose a three-dimensional (3-D) USBL based UWAL method utilizing the modified Newton algorithm. Firstly, a modified Newton algorithm is proposed by introducing the singular value factor to address the non-convergence problem, which dramatically deteriorate the localization precision in the traditional Newton algorithm. Secondly, a localization node selection algorithm is presented to optimize the localization precision and reduce the computational burden. Moreover, the localization precision analysis is implemented to evaluate the theoretical performance of the method. Finally, simulation and lake trial results prove the effectiveness of the method.

Summary: Ilizarov discovered the phenomenon of rich vascular network formation during distraction osteogenesis for limb regeneration and functional reconstruction. The tension-stress rule could activate and enhance the regenerative potentials of living tissues, leading to growth or regeneration of muscles, fascia, blood vessels, and nerves simultaneously. Orthopaedic surgeons in China applied the tibial cortex transverse transport (TTT) technique to reconstruct limb microcirculation, to treat lower extremity microvascular lesions and diabetic foot ulcers since 2001. Clinical studies from China demonstrated that the TTT technique could effectively regenerate the microvascular network in the lower limbs of diabetic patients, promote ulcer healing and reduce the amputation rate. As a novel treatment for severe Diabetic Foot Ulcers (DFU), the TTT technique may be adopted in different countries to benefit DFU patients worldwide. This guideline is initiated by the Chinese Association of Orthopaedic Surgeons (CAOS) TTT Technique for Diabetes Foot Taskforce Group. This guideline provides clear recommendations for indications, contraindications, principles for surgical procedures, preoperative and postoperative management, which maximize the success rate for TTT surgery in treatment of severe DFU. The translational potential of this article: This guideline provides clear recommendations for indications, contraindications, principles for surgical procedures, preoperative and postoperative management, which maximize the success rate for TTT surgery in severe DFU treatment. This guideline serves as a starting reference for those who are interested or about to carry out TTT surgery. As an alternative novel treatment for severe DFU, we hope that the TTT technique may be adopted in different countries soon to benefit DFU patients worldwide.

Undoubtedly, these days our telecommunication networks are witnessing not only a major spike is data volumes, but also a shift in the mode of communications. Employees, news anchor and students are conducting their daily business and learning activities through online platforms as they shelter homes during this pandemic and this is expected to continue for some time. An overwhelming shift to one-to-many and many-to-many communications is observed and end users expect from their providers efficient, secure and reliable services. Operators of digital platforms are challenged to respond quickly to the rising demand, by enhancing deployability and manageability of their service. Virtualization is a key enabler for enhanced deployability and manageability where virtual functions can be automatically deployed on demand. Another challenge that providers deal with is the individualized requirements by services offered to users which may vary between high reliabilities, low latency, robust security and any combination thereof. This paper considers the problem of provisioning multi-source multicast services where each service consists of a set of in-network virtual functions that must be chained in a particular order to meet the quality of service demanded by end users. We deal with a reliable service where reliability is attained by provisioning backup functions for the service. We first calculate the requirements of VNF backups which account for fewer computing resource consumption. Next, we formulate the multi-source multicast hybrid routing as a Mixed Integer Linear Programming (MILP) and find a solution with optimal VNF placement and traffic routing. We also proposed a K-shortest path-based greedy algorithm to reduce the complexity for solving MILP. Numerical analysis and simulations are conducted to validate the proposed algorithms. Our results show multi-source multicast has a better routing selection compared to single-source multicast due to the more options of multicast sources for providing a reliable network service.

The understanding of Ilizarov’s biological principles is guiding clinical treatment. Ilizarov’s First Principle of Biology, Distraction Histogenesis, is a fundamental guidance for bone lengthening. The “Harbin Phenomenon” is an extension of “Transformation Histogenesis”, which was discovered by bone transport for bone defects treatment. It describes the transformation and regeneration capacities of scar tissues under slow and rhythmic distraction, and this transformation satisfies the morphological and functional requirements. This principle is a supplement to the first principle, and could be Ilizarov’s Second Principle of Biology. Together they form the basis to guide clinical bone transport treatment.

The Ilizarov external mini-fixator (IEMF) has become an effective tool for the treatment of acute and chronic hand and foot injuries and deformity correction due to its advantages of easy fixation, good holding power, and artful appearance. However, there are relatively few clinical reports on this technique. Materials and methods From June 2019 to March 2021, we preformed IEMF on 113 patients with open phalanx fractures as emergency surgery, and all patients had 3–6 months follow-up. Results All fractures achieved clinical healing. Among them, pin site infection occurred in 8 fractures (7.07 %), arthrolysis occurred after 6 fractures (5.3 %), and 4° rotation malunion occurred in 3 cases (2.65 %).

Summary: Lymphoedema is a debilitating condition, manifesting in excess lymphatic fluid and swelling of subcutaneous tissues. It is as of yet still an incurable condition and current treatment modalities are not satisfactory. In this report, a new surgical technique---tibial cortex transverse distraction (TCTD) is tried for the treatment of this disease. A 59-year-old women with primary lymphoedema had obvious edema and aching of her right lower limb for six months. The patient received the surgery of TCTD: a corticotomy window (length∗width, 5 cm∗1.5 cm) was opened on her right medial upper tibia. With an external fixator, the bone window was given a daily distraction for two weeks. The aching of the right lower limb was lessened in the second day postoperatively and disappeared on the 10th day after the surgery. The edema of limb decreased slowly but steadily at the following six months.The discussion includes the possible mechanisms of TCDT and its usage in the treatment of other diseases. This surgery could play a role for lymphedema treatment and merits further studies. The translational potential of this article: ”The surgery of tibial cortex transverse distraction has the potential to improve the symptoms of limbs lymphoedema.”

The characterization of monolignols H-, G- and S- units composition Vanholme et al. (2010) of lignin is important in agriculture, forestry, herb medicine, livestock, and health care research Vanholme et al. (2008) and Sticklen (2008). The conventional methods often require a great deal of samples and reagents and are time-consuming. Here, we present a newly developed method with fewer operations. The optimized method is suitable for detecting and characterizing lignin composition of cell wall in different plant species and has the advantages of: • Avoiding the influence of plasticizer by plasticware and enhancing the accuracy of monolignols analysis. • Lowering the required samples from grams to milligrams, and organic reagents from milliliters to microliters. • Reducing the time required from a few days to 6 h. Method name: Rapid, simplified microscale quantitative analysis of lignin H/G/S composition with GC–MS in glass ampules and glass capillaries, Keywords: GC–MS, Monolignol, Ampule, Capillary, Thioacidolysis

Ilizarov’s tibial transverse transport (TTT) technique can promote vascular regeneration. It has been used in the treatment of a variety of lower limb ischemic diseases, such as thromboangiitis obliterans, diabetic foot ulcers, etc. Recently, several novel therapeutic effects have been discovered based on TTT treatment. For instance, in the treatment of thromboangiitis obliterans, an “Open Skylight Effect” was well defined in which the symptom of resting pain disappeared following tibial cortex osteotomy (Long Qu, 2001). During the treatment of bilateral diabetic foot gangrene, patients that received TTT treatment on the one side of the lower limb were observed to have a simultaneous healing of ulcers on both sides, which was termed as the “Summon Effect” (Qikai Hua, 2017). In 2019, we characterized the above discoveries as the “Twin Open Skylight and Summon Effects”. These findings will inspire more potential clinical applications of TTT technique.

Determination of accurate dosage of existing antibiotics and discovery of new antimicrobials or probiotics entail simple but effective methods that can conveniently track bacteria growth and inhibition. Here we explore the application of a previously reported fluorogenic E. coli-specific DNAzyme (catalytic DNA), RFD-EC1, as a molecular probe for monitoring bacterial inhibition exerted by antibiotics and for studying bacterial competition as a result of cohabitation. Because the DNAzyme method provides a convenient way to monitor the growth of E. coli, it is capable of determining the minimal inhibitory concentration (MIC) of antibiotics much faster than the conventional optical density (OD) method. In addition, since the target for RFD-EC1 is an extracellular protein molecule from E. coli, RFD-EC1 is able to identify pore-forming antibiotics or compounds that can cause membrane leakage. Finally, RFD-EC1 can be used to analyse the competition of cohabitating bacteria, specifically the inhibition of growth of E. coli by Bacillus subtilis. The current work represents the first exploration of a catalytic DNA for microbiological applications and showcases the utility of bacteria-sensing fluorogenic DNAzymes as simple molecular probes to facilitate antibiotic and probiotic research.

Prediction accuracies of estimated breeding values for economically important traits are expected to benefit from genomic information. Single nucleotide polymorphism (SNP) panels used in genomic prediction are increasing in density, but the Markov Chain Monte Carlo (MCMC) estimation of SNP effects can be quite time consuming or slow to converge when a large number of SNPs are fitted simultaneously in a linear mixed model. Here we present an EM algorithm (termed "fastBayesA") without MCMC. This fastBayesA approach treats the variances of SNP effects as missing data and uses a joint posterior mode of effects compared to the commonly used BayesA which bases predictions on posterior means of effects. In each EM iteration, SNP effects are predicted as a linear combination of best linear unbiased predictions of breeding values from a mixed linear animal model that incorporates a weighted marker-based realized relationship matrix. Method fastBayesA converges after a few iterations to a joint posterior mode of SNP effects under the BayesA model. When applied to simulated quantitative traits with a range of genetic architectures, fastBayesA is shown to predict GEBV as accurately as BayesA but with less computing effort per SNP than BayesA. Method fastBayesA can be used as a computationally efficient substitute for BayesA, especially when an increasing number of markers bring unreasonable computational burden or slow convergence to MCMC approaches.