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Pediatric intracranial germ cell tumors (GCT) are clinically rare but highly heterogeneous tumors, primarily occurring in children and adolescents. The treatment method depends on the tumor type. Pure germinoma can be cured with radiotherapy and chemotherapy, while mature teratomas can be cured with surgical resection. Non-germinomatous germ cell tumors (NGGCT) require comprehensive treatment. Current domestic and international guidelines or expert consensus recommend initial chemotherapy, followed by surgical resection for those not achieving complete remission. However, clinical practice has found that surgery risks increase after chemotherapy, leading some experts to advocate for direct surgery. Beijing Tiantan Hospital, Capital Medical University proposed a clinical diagnosis and treatment strategy for pediatric intracranial NGGCT (2023 Tiantan version), recommending joint evaluation by neurosurgeons and oncologists for individualized treatment to provide better treatment plans for children.

The fumigant has been approved by the World Health Organization for use in grain storage, targeting the eradication of pests in areas where grain is stored or transported to reduce insect and mold activities, thereby minimizing storage losses. Phosphine is featured by its economic viability, application readibility, rapid diffusion, and lack of residue, making it advantageous for comprehensive pest control. It demonstrates high efficacy against various harmful organisms in storage, making it one of major fumigants worldwide. However, the elimination of some fumigants has increased dependence on phosphine. The lack of standardized guidance and inappropriate use of phosphine have led to severe resistance among stored grain pests, posing a threat to the effectiveness and sustainability of phosphine treatment. This paper provides a comprehensive review of the current status and trends of phosphine resistance in stored grain pests on the global. It analyzes the genetic basis of resistance, focusing on respiratory and cuticle-related gene expression and detoxification enzyme mechanisms. A comparison of four resistance detection methods—FAO, discriminating does bioassay, rapid knockdown, and molecular identification—is rendered. The study explores key strategies for resistance management, including optimization of fumigation protocols, laboratory and field validations, and application recommendations. The aim is to offer reference information for the scientific and rational use of phosphine and the development of alternative pest control methods in the future.

With the advancement of the national goal of “double carbon”, the hydrogen production by electrolytic water will usher in explosive growth, among which the topology and control of power supply is of great significance to improve the efficiency of hydrogen production system. This paper took the topology of isolated DC/DC hydrogen production power supply as the main line to sort out and analyze, and summarized and analyzed the structures, advantages and disadvantages of single-stage, two-stage, parallel and multi-port DC/DC isolated hydrogen production power supply according to different application scenarios. The analysis shows that the full-bridge resonant converter and the control scheme considering the temperature, pressure and hydrogen/oxygen cross-osmosis feedback of the electrolytic cell will become the development trend of high-power large-scale hydrogen production power supply which can adapt to wide range and strong fluctuation. Moreover, the isolated three-port DC/DC conversion power supply will become the distributed integrated electric-hydrogen coupling development mode in the future. The research of this paper aims to provide theoretical reference for the further research of hydrogen production by electrolytic water.

Pediatric neurosurgery, encompassing a range of conditions such as childhood brain tumors, congenital neural tube defects, hydrocephalus, traumatic brain injury and cerebrovascular diseases, has seen considerable advancement in China since its inception in 1960. Through sustained efforts across generations of physicians, the field has evolved from nonexistence to a position of strength, currently leading globally in the volume and diversity of clinical cases. Despite these strides, challenges persist, notably the shortage of specialized surgeons, regional discrepancies in medical care standards, and a dearth of clinical guidelines. The advent of technologies such as artificial intelligence, brain-computer interfaces, and virtual reality presents unprecedented opportunities for rapid advancements in diagnosis and treatment standards. The onus lies on China's pediatric neurosurgery community to leverage this technological evolution, and fulfill their collective mission and responsibility.

In this paper, a state-space method for double-beam systems with variable cross sections is developed, making it possible to calculate the transverse vibration of the double-beams accurately and effectively. Due to the variability in the double-beam cross sections with the viscoelastic interlayer in between, the governing equations of vibration for the systems become highly coupled partial differential equations, making the problem difficult to solve. A basic double-beam system is introduced to modify the original governing equations to two inhomogeneous differential equations. Given the separation of variables, several mode-shape coefficients and a state variable are defined to construct the state-space equations. The coupling terms and variables are transferred into the constant coefficient matrix of the state-space equations, decoupling them. Numerical procedures are presented to solve the state-space equations to obtain homogenous and inhomogeneous solutions, including the natural frequencies and mode shapes in free vibration and the dynamic responses in forced vibration, respectively. The method has substantial advantages in decoupling high-order partial differential equations and can be further extended to solve complex structural systems. Numerical results also demonstrate that the method is accurate and efficient. Finally, an engineering application with a rail-bridge with a floating slab track is discussed in detail with the method.

Iron III (Fe3+) sensing is of great importance for monitoring its levels in different environmental and biological systems since its levels are tightly associated with many environmental concerns and serious diseases. Compared to the ordinary Fe3+ detection methods involving the sophisticated and expensive instruments, the use of fluorescent materials with short response time and low cost attracts much attention. Amongst a variety of fluorescent materials, a nitrogen-doped carbon dot (N-CD) is emerging as promising luminescent materials for biosensing due to their superior photoluminescent properties, good water solubility, and biocompatibility. Herein, N-CD prepared via a green and cost-effective one-pot hydrothermal method using a new single precursor N-(2-hydroxyethyl) ethylenediamine triacetic acid (HEDTA) as both the carbon and nitrogen sources is reported. The blue fluorescent emission of N-CDs is quenched by the addition of Fe3+, and the quenching intensity is concentration dependent in the wide range (0.76–400 μM) with a detection limit of 0.16 μM. The quantum yield for the as prepared N-CDs is 14.17%. The N-CDs also show a high selectivity for Fe3+ chelation amongst a range of biological metal ions. The fluorescent quenching is attributed to the formation of the coordinate covalent bonds between the Fe3+ and N-CDs, and the mechanism is proved to be a static type on the basis of the photoluminescence lifetime and the temperature-dependent fluorescent intensity change. Our eco-friendly and simple strategy will benefit the application of CDs in various fields. Keywords: N-(2-hydroxyethyl) ethylenediamine triacetic acid (HEDTA), Nitrogen-doped carbon dot (N-CD), Metal sensing, Iron III, Quenching mechanism

Fe-17Cr-4C-2V-Mn-Si-Ti complex system hardfacing alloys were deposited by using flux-cored wire self-shielded open arc welding. The effects of silicon on their M7C3 ( M =Fe, Cr, V, Mn) phases and abrasion resistance were investigated by OM, XRD and SEM. The results show that, with silicon content increasing from 0.6%(mass fraction) to 2.4%, the size of primary M7C3carbides gradually reduces and transites from rod-like shape to block-like shape in dispersion distributing state. γ-Fe phases, which adjacent to those primary M7C3 grains, progressively reduce until disappear. It dues to that silicon can change the precursor of primary M7C3 nucleates in nature, e.g. liquid high carbon atom clusters and it results in the change of their morphology, distribution and size. The wear test results indicate that the abrasion resistance of open arc hardfacing alloys improves firstly and then reduces when silicon content increases from 0.6% to 2.4%. The optimum abrasion resistance is acquired at 1.5%Si. The analysis on the surface worn morphologies show that the micro-cutting and micro-spalling wearing mechanisms coexist.

The unified theoretical frame of a joint transmitter-receiver reduced dimensional Space-Time Adaptive Processing (STAP) method is studied for an airborne Multiple-Input Multiple-Output (MIMO) radar. First, based on the transmitted waveform diverse characteristics of the transmitted waveform of the airborne MIMO radar, a uniform theoretical frame structure for the reduced dimensional joint adaptive STAP is constructed. Based on it, three reduced dimensional STAP fixed structures are established. Finally, three reduced rank STAP algorithms, which are suitable for a MIMO system, are presented corresponding to the three reduced dimensional STAP fixed structures. The simulations indicate that the joint adaptive algorithms have preferable clutter suppression and anti-interference performance.

In order to realize the dynamic and scientific optimization of production plans for multi-metal underground mines,we convert underground mining processes into a mathematic model constrained by several conditions to meet technical and economic requirements as well as spatial sequence relation,which aims to maximum profits. Operating units including cutting,blasting,mining and filling are treated as a whole process in the model. The underground mining condition of equilibrium and continuity is transformed into a space constraint. Considering the mining state of ore blocks as the decision variable,a model of production planning optimization is constructed by binary integer programming and calculated by an algorithm based on the artificial bee colony model. The optimization model was applied in a multi-metal underground mine in Tibet in southwestern China to optimize the production plan in the next three years which was illustrated by three-dimensional visualization display. The optimal solution indicated that the dynamic adjustment of the mining area could guarantee continuous production and increase the economic benefit of mine exploitation.

The definition of self-compacting concrete is briefly introduced. The research process of self-compacting concrete in various countries in the world is studied, from the initial test to the final formation of the preliminary application specification, and it is constantly improved. The mix proportion design, working performance, testing method, application and research status of self-compacting concrete are discussed in detail, and the problems to be solved in the future and the development prospect are prospected

In order to cope with the growing environmental pollution triggered by traditional disposable express packing box, the design and promotion of recycling express packing boxes (REPB) is of necessity and feasibility. However, relevant research is still lacking. To address the aforementioned issues, this paper attempted to propose a comprehensive method for designing REPB based on five intelligent functions of REPB, i.e., information processing, transportation environmental state perception, transportation environment interaction, human-machine interaction, and cloud interaction. Additionally, to ensure the reliability and safety of REFB, this paper discussed the material and structure of REPB based on shock absorption, as well as the intelligent functions to protect REFB from being stolen and lost. This paper can aid in the establishment of framework for REPB design pertaining to intelligence, safety, feasibility and reliability. Future research could further explore the standardization of REFB.

A method of discovering multi-step attack patterns from alert data was studied.Alert similarity function was defined to construct the set of attack activity sequences.Sequence alignment technology was used to cluster the similar attack activity sequences.Multi-step attack patterns in a cluster were automatically discovered by the longest common subsequence extraction algorithm based on the idea of dynamic programming.The proposed method didn’t depend on large amounts of prior knowledge.Few configuration parameters were needed and it was easy to implement.Experimental results demonstrate the effectiveness of proposed method.

To overcome the shortcoming of current alert correlation methods which didn’t consider the confidence of IDS,an alert correlation method based on alerts confidence using the evidence theory was presented.Each alert was regarded as a piece of evidence of a network attack.Then multiple pieces of evidence were combined by the Dempster’s combina-tion rule,and used to infer whether the attack corresponding to the alerts took place.As a result,the ambiguity and con-fliction in alerts were eliminated,achieving the goal of improving alerts quality.Experimental results on the DARPA 2000 IDS test dataset show that the proposed method can efficiently decrease the false alert rate and reduce more than 60% of the alerts.

This paper put forward an intelligence system for controlling the landfill gas in landfills to make the landfill gas (LFG) exhaust controllably and actively. The system, which is assigned by the wireless sensor network, were developed and supervised by remote applications in workshop instead of manual work. An automatic valve control depending on the sensor units embedded is installed in tube, the air pressure and concentration of LFG are detected to decide the level of the valve switch. The paper also proposed a modified algorithm to solve transmission problem, so that the system can keep a high efficiency and long service life.

A novel sampling method,IDSampling,was developed to solve the performance unbalance problem that IDS could not scale well in G+bit/s link,which was adaptive with the consumption of the memory bottleneck.With the help of the heuristic messages,such as the entropy of the single-packet flow and the flow length,IDSampling applied the simple sampling strategy based on the entropy of the single-packet flow when the large-scale anomaly occurred,or another complicated one instructed by the feedback of the rear detection results by default.In both cases IDSampling tried to guaran-tee the equal security with detection cost as low as it could.The results of experiment show that ①IDSampling keeps IDS effective by cutting off its load significantly when it is overloaded,at the same time it can guarantee the detection accuracy of the large-scale attack;②Comparing with the other two overwhelming sampling methods,the random packet sampling and the random flow sampling,the number of attack packets sampled by IDSampling is higher than that of the former two,the number outweighs the former two one order of magnitude especially in the large-scale anomaly case.

A noninvasive,single-ended objective quality assessment method called "FSPAV",which only utilized IP flow features to predict the perceived quality of VoIP service （PQoS） was proposed. The cores of the method are three PQoS related metrics of flow features. It only needs to monitor IP packets containing voice data from the peer user received by a local end user to calculate metrics,with no need to synchronize clocks or parse application protocols. A measure of the individual truth grad is used to map the measurement values of three metrics on a call segment into a single speech qual-ity prediction. During the calculation,the goodness grad for each flow feature can also be derived. Talk experiments on the Internet by using VoIP software QQ and Skype was presented. The experimental results show that the objective as-sessments correlate well with subjective ones,which indicates that the method proposed here is effective.

For improving the accuracy of IDS evaluation,after the detection method of signature-based IDS was analyzed,pointed out that the current methods are not reasonable,and proposed the principle to evaluate the capability of IDS im-plementation and the capability of rule base respectively.The method to evaluate the capability of IDS implementation,which views the human knowledge as parameters,was introduced.The definition of metrics and how to calculate the value of metrics are mainly discussed.A prototype was implemented which shows that this new method can evaluate the real capacity better for a signature-based IDS.