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Background The anatomical position of the mandibular third molars(M3)is located in the posterior space of the molars, and many two-dimensional studies on them in the previous literature. This study evaluated the relationship between retromolar space(RS) and different impacted classifications of M3 in three‑dimensional(3D) cone‑beam computed tomography(CBCT). Methods 206 mandibular third molars from 103 patients were included and separately separated into three classifications concurring to four classification criteria which included PG-A/B/C, PG-I/II/III, mesiodistal angle and buccolingual angle. 3D hard tissue models were reconstructed by CBCT digital imaging. RS was measured respectively by utilizing the fitting WALA ridge plane (WP)which was fitted by the least square method and the occlusal plane(OP) as reference planes. The SPSS (version 26) was used to analyze the data. Results In all classifications of classification criteria, RS diminished steadily from the crown to the root (p 0.05). Conclusions RS were related to the impacted classifications of M3. With the increment of the impacted degree of M3 ,the retromolar space gradually diminished. In clinic, RS can be evaluated by watching the PG classification and mesial angle of M3.

In the present study, the predictive role of the percentage of the solid portion volume (PSV) in patients with lung adenocarcinoma was investigated. The PSV was obtained through quantitative volumetric assessments based on reconstructed CT images of lung adenocarcinoma by comparing the index among tumors with c-ros oncogene 1 (ROS1) rearrangement, epidermal growth factor receptor (EGFR) mutations, echinoderm anaplastic lymphoma kinase (ALK) rearrangements or wild-type (WT) status for the three genes. Among 1,120 patients with lung adenocarcinoma, 28 patients with ROS1 rearrangement lung adenocarcinoma, 71 with ALK rearrangement and 578 with EGFR mutations were diagnosed. PSV was quantitatively measured by semi-automated nodule assessment software and compared in patients with different mutation statuses. The PSV (presented as the median with interquartile range) in the ROS1 rearrangement group [87.9 (82.7–92.3)%] was higher than that in the EGFR mutation group [70.4 (51.4–83.4%)] and the WT group [63.0 (50.9–83.2)%; P

From the perspective of targeting factors, iron acetylacetonate and nickel acetylacetonate were used as major materials, and oleylamine was used as a solvent. Through thermal decomposition, the uniformly distributed nanoparticle FeNi3 was obtained. Then, the α-methyltryptophan (AMT) was used to modify FeNi3, thereby the material (FeNi3-AMT) would be biocompatible. The prepared material was used as a targeting factor to explore whether it could target the epileptogenic focus in temporal lobe epilepsy model rats. In the experiment, the animal models of temporal lobe epilepsy were constructed by using the lithium chloride-pirocarpine method. According to the injection of the nuclear magnetic factor, the models were divided into the FeNi3 group, the FeNi3-AMT group, and the saline group. The model rats received intravenous injections 48 hours after the onset of epilepsy. The activity of the epileptic seizure sites before and after injection, the penetration of nanoparticles, and the toxic and side effects of the material were compared. The results showed that the rat models of temporal lobe epilepsy were successfully constructed (the success rate was more than 85%). Meanwhile, the epilepsy lesions of the rat models added with nanoparticles were darker (P < 0.05). The staining of rat brain sections confirmed the distribution of iron particles. In the FeNi3-AMT group, there were more iron particles distributed (P < 0.05). In addition, various abnormal neurons appeared in the hippocampus of the three groups, and there was no significant difference between the different groups (P < 0.05). There was no significant difference in the number of positive neurons in the CA3 region of the brain between different groups (P < 0.05). However, the imaging effect based on FeNi3-AMT was more prominent (P < 0.05), which confirmed that the FeNi3-AMT group had better targeting location effects. The study confirmed that the iron nano alloy particle material had excellent application values in the localization of temporal lobe epilepsy.

A novel shaking table substructure testing method that includes interaction forces determined by actuator forces and shaking table dynamic parameters is proposed and validated. The seismic performance of a storage tank that incorporates soil-structure interactions is investigated by the method proposed in this article. The experimental results show that the proposed shaking table substructure testing method is an efficient alternative method of evaluating the seismic performance of a storage tank that incorporates soil-structure interactions. The experimental results show that the influence of the soil-structure interactions increases as the stiffness of the foundation soil decreases, which was demonstrated by the results showing that the displacement and acceleration responses of the storage tank decrease as the stiffness of the foundation soil decreases. Moreover, the influence of the soil-structure interactions increases as the liquid height increases, which was illustrated by the decreased displacement responses of the storage tank with increases in the liquid height. The maximum acceleration response of the storage tank occurred at the liquid surface height.

This study aimed to evaluate the effects of malnutrition on the hypothalamic-pituitary-ovarian axis (HPOA) sex hormones in female rats with coal burning-type fluorosis. Female rats were divided into four groups: control, malnutrition, fluorosis, and fluorosis with malnutrition. Rats in the control and malnutrition groups were fed pollution-free corn with either regular or low protein content. Rats in the fluorosis and fluorosis with malnutrition groups were fed corn roasted with coals from the fluorosis endemic areas of Zhijin, China,with either regular or low protein content. Results revealed that the body weight of rats with protein malnutrition was significantly reduced compared with that of the control and fluorosis rats. Urinary fluoride was significantly decreased and bone fluoride was significantly increased in the fluorosis with malnutrition group compared to the fluorosis group. Moreover, protein malnutrition significantly enhanced the effect of fluoride on gonadotropin-releasing hormone, follicle-stimulating hormone, luteinizing hormone, and testosterone. Histological and ultrastructural analyses revealed that protein malnutrition intensified fluoride-induced ovary damage. Malnourishment could promote the abnormal secretion of HPOA sex hormones in females with fluorosis.

Sanggenon C (SC), a natural flavonoid extracted from Cortex Mori (Sang Bai Pi), is reported to possess anti-inflammatory and antioxidant properties in hypoxia. The present study aimed to investigate the therapeutic potential and the underlying mechanisms of SC in cerebral ischemia-reperfusion (I/R) injury. A rat model of reversible middle cerebral artery occlusion (MCAO) was used to induce cerebral I/R injury in vivo, and SC was administrated intragastrically. Brain injuries were evaluated using Bederson scores, brain water content, and 2, 3, 5-triphenyltetrazolium chloride (TTC) staining. The levels of inflammatory factors and oxidative stress were examined using corresponding kits. Cell apoptosis was evaluated by TUNEL. Moreover, the expressions of apoptosis-related and RhoA/ROCK signaling-related proteins were detected through western blotting. In vitro, RhoA was overexpressed in oxygen-glucose deprivation and reperfusion (OGD/R)-induced PC12 cells to confirm the contribution of RhoA-ROCK signaling inhibition by SC to the neuroprotective effects post OGD/R. Pretreatment with SC significantly ameliorated the neurologic impairment, brain edema, and cerebral infarction post MCAO-reperfusion, associated with reductions of inflammation, oxidative stress, and cell apoptosis in the brain. Furthermore, SC remarkably downregulated the expression of RhoA/ROCK signaling-related proteins post MCAO-reperfusion in rats, while overexpression of RhoA reversed the beneficial effects of SC on protecting against inflammation and oxidative stress in OGD/R-induced PC12 cells. Taken together, these findings demonstrated that SC exerts neuroprotective effects after cerebral I/R injury via inhibiting inflammation and oxidative stress through regulating RhoA-ROCK signaling, suggesting a therapeutic potential of SC in cerebral I/R injury.

We proposed a meta-waveguide, a component based on metamaterials and waveguides, to customize the phase and absorption of devices. This meta-waveguide integrated quasi-periodic metamaterial resonators with film resistors in the inner wall of the waveguide. The phase and absorption at multiple specified frequency points could be changed regularly by adjusting the resonators and film resistors. We analyzed the meta-waveguide structure and derived a transcendental equation, which revealed the physical mechanism of phase control. In addition, we proposed an equivalent circuit model to explain the mechanism of absorption control. Then, a customized meta-waveguide that works from 90 to 100 GHz was designed, fabricated, and demonstrated.

Rubber-absorbing material patches have been extensively applied in various fields because of its softness, excellent adhesive property, and moldability. However, the material undergoes thermal aging when used in a high-temperature environment for a long time. Therefore, the mechanism through which the properties change with aging must be elucidated. This work mainly aims to analyze the electromagnetic and mechanical properties of such materials during thermal aging. Methyl vinyl silicone rubber (VMQ) was loaded with 45 vol% carbonyl iron powder (CIP) and subjected to accelerate thermal aging. The electromagnetic and mechanical properties were measured with a network analyzer and electronic tensile testing machine, respectively. Results confirmed the increase in the complex dielectric constant, the decrease in the band width of reflection loss (RL) ≤ −10 dB, and the lack of significant change in permeability. The tensile strength, tear strength, and Shore A hardness of CIP/VMQ composite-absorbing materials evidently increased, but the elongation at break sharply decreased after hot air aging at 200°C for 14 days. POLYM. COMPOS., 2017. © 2017 Society of Plastics Engineers

Background This study was conducted to summarize the clinical, magnetic resonance imaging (MRI) and pathological features of IgG4-realated hypertrophic pachymeningitis (IgG4-RHP) and its differential diagnosis from similar diseases. Methods Data of IgG4-RHP patients admitted to Department of Neurology, Neurosurgery and Infection, the First Affiliated Hospital of Medical School of Zhejiang University from January 1, 2015 to July 31, 2019 were collected and their clinical symptoms, laboratory examinations, imaging and pathological features were investigated. At the same time, the clinicopathological and imaging findings of other dura thickening diseases diagnosed in our hospital were compared and analyzed. Results The clinical symptoms of 4 IgG4-RHP patients include chronic headache and cranial nerves injury, etc. Levels of serum IgG4 and cerebrospinal fluid (CSF) IgG4 increased in all patients. Focal enhancement of dura mater could be seen on plain and enhanced cranial MRI. Pathological results were consistent with IgG4-RHP symptoms. Among other diseases that cause dural thickening, the content of serum C-reactive protein in patients with Rosai-Dorfman disease declined. Patients with intracranial hypotension syndrome often have postural headache. Patients with tuberculous meningitis can have previous pulmonary tuberculosis. The diagnosis of patients with atypical meningioma depends on the results of operation and pathology. Patients with central nervous system leukemia can be diagnosed with reference to the results of laboratory results. Conclusions The clinicopathological and imaging manifestations of IgG4-RHP are summarized in this study. Meanwhile, the clinical data of several other diseases with similar imaging characteristics are analyzed in order to clarify the diagnostic strategy of IgG4-RHP and provide help for the next treatment.

The service period of insurance products is often a period of time after purchasing products. Therefore, using the existing information to assess the future solvency of the insurance company is very important to the policyholders' insurance purchase decision and equivalently important to the operation of the insurance companies. Our research sets up a model to predict the solvency of the property insurance companies in the coming year, focusing on whether the two indexes of the company size and the current solvency adequacy ratio are strong and reliable, and to provide support for policyholders' insurance purchase decisions. We show that, contrary to the conventional thought that big companies are more solvent, company size has a negative impact on its future solvency. And the current solvency adequacy ratio is a reliable index to predict the future solvency so that our research results also indicate the regulatory supervision of solvency is beneficial to take action to protect the interests of the policyholders as soon as possible.

This paper uses simulation methods to verify the reliability of applying glass ferroaluminium alloy laminates to subway fan blades. Through the force analysis of its blades, it is found that the material has a wider application prospect in subway fan blades, and it can achieve better energy-saving effects than the existing aluminium alloy blades.

The invention designs a smart storage shoe cabinet for the existing home storage shoes, which can bring convenience to the family to access the shoes. Mainly divided into storage module and shoe rack module, the two are independent of each other, according to the size of the household and the needs of the household shoe cabinet, the storage module and drive module for combined deformation and unitization treatment.

Noise impact is the most sounds are subjective evaluation, hearing, and can significantly affect human health and wellbeing. The effects of noise on the human body include hearing loss, impaired growth and development, overall tension, and sleep disturbance in children and adolescents, and decreased ability to the building environment safety. Although it is difficult to classify the specific effects of noise, noise affectless is also considered by many ecologists to be destroying or eliminating, and pollution plays an important role. FPGA (field-programmable gate array) is used to measure and estimate the instantaneous amplitude of environmental noise and uses advanced architecture for picking up noise-polluted audio signals. A high-performance algorithm refers to the number of arithmetic operations (multiplication, division, and addition) noise value are calculate the output value of a system. Memory Requirements Specifies the amount of memory needed to store system parameters, past input, output past, and any intermediate calculated values. The effect of limited accuracy means that the quantitative effect is inherent in the implementation of any digital system. High-performance algorithm technique for cancel the noise in the desired signal. Environmental noise must be correlated with the noise component of the audio signal in order to be positively correlated and effectively removed.

Night-time excessive luminance Outdoor LED display screens (OLDSs) are widely used in urban areas, which yield potential safety hazards to vehicle traffic at night. In this study, we evaluated the effects that coloured light projected from excessive luminance OLDS has on vehicle driving safety along urban roads at night. Based on road lighting environmental characteristics at night and using reaction time (RT) testing software under different white field luminance (WFL) conditions, the RTs for small targets (STs) with different colours of OLDS were examined. First, in combination with field tests, excessive luminance values of typical OLDSs at night (1,000, 3,000, and 5100 cd/m2) were determined; then, experimental simulation scenes were established by integrating real photos with software simulations. Next, the RT experiments were conducted, followed by obtaining the influences that different colours have on the RTs and visual missing dots (MDs) under different WFL conditions. The results showed that, in addition to blue light, the coloured light of OLDSs can improve a driver's ability to recognise small targets and reduce RTs in the case of low WFL values, but the coloured light causes more MDs and affects traffic safety. The findings also indicated that the night recognition abilities of females under the influence of projected OLDS coloured light was better than that of males.

Plate-like Zn2W barium hexagonal ferrites were prepared using a combined coprecipitation and molten salt method. The thermal decomposition behavior of precipitates was systematically studied by TG–DSC and XRD. Pure plate-like Zn2W barium hexagonal ferrites with optimal properties were obtained at a synthesis temperature of 1150 °C for 1 h. Phase composition, morphology and magnetic properties of the Zn2W ferrite powders synthesized at different temperatures (1100–1250 °C) and different holding times (0.5–3 h) were investigated by XRD, SEM and VSM. The electromagnetic parameters were studied by VNA. Saturation magnetization of Zn2W ferrite synthesized at 1150 °C for 1 h reached the maximum of 76.24 emu/g, whereas coercivity decreased with the increase in synthesis temperature and holding time.

The purpose of this project is to apply the principle of Laval nozzle to reconstruct the gas stove, improve the combustion efficiency of the gas stove, transform its tail gas products, and reduce the tail gas pollution of the gas stove. In this paper, ANSYS software is used to simulate the Laval nozzle of micro modular liquefied gas micro propulsion system, and the relationship between the size factors of the nozzle and the flow effect of liquefied gas is obtained.

In large-scale wireless sensor networks, a low energy consumption requirement in data communication has become more prominent, but the currently existing solutions are unsatisfactory. Based on the complexity and uncertainty in the node energy consumption and communication path in wireless sensor networks, this paper proposes a low energy adaptive clustering multi-hop routing protocol based on fuzzy decision (FD-LEACH). In order to constitute a dynamic network routing structure, the protocol introduces the concept of fuzzy set and uses the theory of fuzzy decision to select excellent communication relay nodes. Analysis and simulation results demonstrate that the proposed protocol is more effectively adapted to large-scale wireless networks, which can provide a better balance in energy consumption and significantly prolong network lifetime.

This paper presents simple and fast algorithms for computing very tight upper and lower bounds on the prices of American Asian options in the binomial model. The authors choose two types sets of the actual arithmetic average prices, instead of the simulated values in other existing models, as the representative average prices at each node of the binomial tree. This approach simplifies effectively the computation and reduces the error caused by the linear interpolation. Numerical results show that the approach produces accurate upper and lower bounds compared to the other existing methods based on the binomial tree.

This article uses overlapping generation (OLG) model to study individuals' optimal decision on consumption, investment, insurance, and education expenses. To the best of our knowledge, we are the first to discuss the individuals' demand for insurance with the consideration of intergenerational transfer payments. In the article, we incorporate insurance into the OLG model to describe individuals' optimization problem on consuming and saving, and we solve the optimal proportions of expenditure on investment, survival insurance, life insurance, and education, with the optimal consumption to be the remaining parts of expenditure. We observe that the numerical outputs are consistent with the actual data. It is also interesting to find that the human capital investment is independent of both risky asset investment and individuals' risk aversion coefficient.

In this paper we investigate the optimal risk control and dividend distribution problem for a diffusion model with a terminal value. Usually the insurer cedes risk by means of a reinsurance contract, and pays dividends out dynamically from the surplus. Consider that the insurer is trying to balance risk control and dividend payout in terms of reinsurance and dividend distribution policies. Then the objective is set to make a dynamic choice of reinsurance policy and dividend distribution policy, which maximizes the sum of the expected discounted dividends up to ruin time and the expected discounted terminal value. There are two novelties in this paper. Firstly, we formulate the optimal control problem in terms of general reinsurance control policies. Each of the proportional reinsurance, the excess-of-loss reinsurance and combination of the two can be treated as a special case. It is shown that, under an expected premium principle, the dynamic excess-of-loss reinsurance is of optimal type within the general reinsurance contracts. Secondly, considering the excess-of-loss reinsurance policy and terminal value, we obtain the explicit expressions for the value function and optimal control policies by solving the HJB equation method. At the end of this paper numerical calculations are done to illustrate the influence of the terminal value on the value function and optimal policies as well.

This paper considers the problem of minimizing the VaR and CTE of an insurer’s retained risk by controlling the combinational quota-share and stop-loss reinsurance strategy. With a constrained reinsurance premium, the authors give the explicit reinsurance forms and the minimal VaR and CTE of retained risk in the case of quota-share after stop-loss reinsurance and the case of stop-loss after-quota-share reinsurance respectively. Finally, the authors conclude that the quota-share after stop-loss is a better reinsurance strategy than stop-loss after quota-share to minimize the VaR and CTE with a same constrained reinsurance premium. And the pure stop-loss reinsurance is preferred for an insurer with a high level regulatory requirement.

Previous work demonstrated that a multi-objective evolutionary algorithm could be successfully employed as an optimiser to make the design of flat-walled multi-layered anechoic linings more efficient. In the present work, such an algorithm is employed to investigate the practical aspects of the application of multi-layered polyurethane foams as the flat-walled anechoic lining. The investigation includes aspects such as the efficacy of a single layer of material, the minimum number of layers of linings to achieve the minimum overall thickness for low (100 Hz), mid (250 Hz) and high (500 Hz) cut-off frequencies, the use of the three-layered lining composite for low to mid cut-off frequencies and the effect of air gaps.

The concept of flat-walled multilayered absorbent linings for anechoic rooms was proposed three decades ago. Flat-walled linings have the advantage of being less complicated and, hence, less costly to manufacture and install than the individual units such as wedges. However, there are difficulties in optimizing the design of such absorbent linings. In the present work, the design of a flat-walled multilayered anechoic lining that targeted a 250 Hz cut-off frequency and a 300 mm maximum lining thickness was first optimized using an evolutionary algorithm. Sixteen of the most commonly used commercial fibrous building insulation materials available in Australia were investigated and fourteen design options (i.e., material combinations) were found by the evolutionary algorithm. These options were then evaluated in accordance with their costs and measured acoustic absorption performances. Finally, the completed anechoic room, where the optimized design was applied, was qualified and the results showed that a l...

Previous investigations indicated that a flat-walled, multi-layered anechoic lining system, with an overall thickness slightly less than a quarter of a wavelength, could be used to achieve a required cut-off frequency. However, the work proved to be tedious and time consuming because of the numerous trial-and-error measurements involved. On the other hand, the successful application of a method of calculating the overall acoustic impedance of multi-layered absorbing systems has indicated that the design of multi-layered absorbing systems can be carried out on a desktop computer. In the present work, a MATLAB genetic and evolutionary algorithm toolbox is implemented as the optimiser to aid and speed up the design process. The optimisation results indicate that a three-layered lining system can achieve results comparable with quality wedge-type anechoic linings with overall thickness slightly less than a sixth of a wavelength at the 100 Hz cut-off frequency.

Computational intelligence (CI) techniques offer powerful alternatives for investigating acoustical issues and providing acoustical solutions to problems. This paper presents information on two CI techniques by applying them to the sound transmission performance prediction and design of floor–ceiling constructions. First a simple neural network (NN) model for predicting the airborne sound transmission of typical floor–ceiling constructions is presented and explained in detail. This model is accessible to researchers with knowledge of neural network analysis (NNA) for further sophistication, specialisation or hybridisation. The model may also be used by architects and others with no knowledge of NNA and no access to any specialised neural network software. Evolutionary algorithms (EAs) were then applied to search the multidimensional space created by the neural network model in order to optimise the airborne sound transmission of floor–ceiling constructions within the range of design parameters utilised in buildings.