Super-resolution diffractive neural network for all-optical direction of arrival estimation beyond diffraction limits.

Wireless sensing of the wave propagation direction from radio sources lays the foundation for communication, radar, navigation, etc. However, the existing signal processing paradigm for the direction of arrival estimation requires the radio frequency electronic circuit to demodulate and sample the multichannel baseband signals followed by a complicated computing process, which places the fundamental limit on its sensing speed and energy efficiency. Here, we propose the super-resolution diffractive neural networks (S-DNN) to process electromagnetic (EM) waves directly for the DOA estimation at the speed of light. The multilayer meta-structures of S-DNN generate super-oscillatory angular responses in local angular regions that can perform the all-optical DOA estimation with angular resolutions beyond the diffraction limit. The spatial-temporal multiplexing of passive and reconfigurable S-DNNs is utilized to achieve high-resolution DOA estimation over a wide field of view. The S-DNN is validated for the DOA estimation of multiple radio sources over 5 GHz frequency bandwidth with estimation latency over two to four orders of magnitude lower than the state-of-the-art commercial devices in principle. The results achieve the angular resolution over an order of magnitude, experimentally demonstrated with four times, higher than diffraction-limited resolution. We also apply S-DNN's edge computing capability, assisted by reconfigurable intelligent surfaces, for extremely low-latency integrated sensing and communication with low power consumption. Our work is a significant step towards utilizing photonic computing processors to facilitate various wireless sensing and communication tasks with advantages in both computing paradigms and performance over electronic computing.

Network pharmacology-based strategy combined with molecular docking to explore the potential mechanism of agarwood against recurrent aphthous stomatitis.

To explore the antiinflammatory mechanism of agarwood on recurrent aphthous stomatitis (RAS). RAS is the most common mucosal disease in the oral cavity. The clinical application of traditional Chinese medicine found that agarwood has significant curative effect on peptic ulcer, but the effect and mechanism of agarwood on RAS remain unclear. This study is intended to predict the potential antiinflammatory mechanisms by which agarwood acts on RAS through network pharmacology and molecular docking. TCMSP database was used to screen the active components of agarwood. RAS targets were screened in Genecards, DisGeNET, and OMIM database. Venny, an online tool, screens for interacting genes between the two. Cytoscape software was used to construct the gene regulation map of active compounds target of agarwood. String Database building protein-protein interaction network. Gene ontology and Kyoto Encyclopedia of Genes and Genomes pathways were enriched in DAVID database. The key active ingredients and core targets were further verified by molecular docking. There were 9 effective compounds and 186 target genes in agarwood; RAS has 793 target genes. There were 41 interacting genes between agarwood and RAS. Interleukin 6, tumor necrosis factor, interleukin 1 beta, and cellular component motif ligand 2 may be key targets. Gene ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analyses predicted multiple pathways associated with RAS. Molecular docking results showed that the active compounds of agarwood combined well and stably with the target. The Chinese herbal medicine agarwood can relieve the inflammation of RAS through multiple targets and various ways. Its active compounds may be nominated as candidates for antiinflammatory drugs of RAS.

Effects of γ-polyglutamic acid supplementation on alfalfa growth and rhizosphere soil microorganisms in sandy soil.

This study aimed at exploring the effects of γ-polyglutamic acid on the growth of desert alfalfa and the soil microorganisms in the rhizosphere. The study examined the effects of varying concentrations of γ-polyglutamic acid (0%-CK, 2%-G1, 4%-G2, 6%-G3) on sandy soil, the research investigated its impact on the growth characteristics of alfalfa, nutrient content in the rhizosphere soil, and the composition of bacterial communities. The results indicated that there were no significant differences in soil organic matter, total nitrogen, total phosphorus, total potassium, and available phosphorus content among the G1, G2, and G3 treatments. Compared to CK, the soil nutrient content in the G2 treatment increased by 14.81-186.67%, showing the highest enhancement. In terms of alfalfa growth, the G2 treatment demonstrated the best performance, significantly increasing plant height, chlorophyll content, above-ground biomass, and underground biomass by 54.91-154.84%. Compared to the CK treatment, the number of OTUs (operational taxonomic units) in the G1, G2, and G3 treatments increased by 14.54%, 8.27%, and 6.84%, respectively. The application of γ-polyglutamic acid altered the composition and structure of the bacterial community, with Actinobacteriota, Proteobacteria, Chloroflexi, Acidobacteriota, and Gemmatimonadota accounting for 84.14-87.89% of the total bacterial community. The G2 treatment significantly enhanced the diversity and evenness of soil bacteria in the rhizosphere. Redundancy analysis revealed that organic matter, total nitrogen, total potassium, moisture content, and pH were the primary factors influencing the structure of bacterial phyla. At the genus level, moisture content emerged as the most influential factor on the bacterial community. Notably, moisture content exhibited a strong positive correlation with Acidobacteriota, which in turn was positively associated with indicators of alfalfa growth. In summary, the application of γ-polyglutamic acid at a 4% ratio has the potential for improving sandy soil quality, promoting plant growth, and regulating the rhizosphere microbial community.

Research on the mechanism of plant root protection for soil slope stability.

In order to investigate the impact of herbaceous root development on soil slope stability in expansive soil areas, the research was conducted in the soil slope experimental area of Yaoshi Town, Shangzhou District, Shangluo City. Three types of herbaceous plants, namely Lolium perenne, Medicago, and Cynodon dactylon, were planted to examine their influence on slope stability. The results indicated that Lolium perenne had significantly higher root length density and root surface area density compared to Cynodon dactylon and Medicago. However, the root weight density of Cynodon dactylon was found to be highest. The roots of Lolium perenne, Cynodon dactylon, and Medicago were predominantly observed in diameter ranges of 0 < L ≤ 1.0 mm, 0 < L ≤ 2.5 mm, and 2.5 < L ≤ 3.0 mm, respectively. The roots of herbaceous plants have the ability to enhance water retention in soil, resist hydraulic erosion of slope soil, and reduce soil shrinkage and swelling. During the initial phase of herbaceous planting, there is an accelerated process of organic carbon mineralization in the soil. The roots of herbaceous plants play a crucial role in soil consolidation and slope protection. They achieve this by dispersing large clastic particles, binding small particles together, altering soil porosity, enhancing soil water retention, and reducing soil water infiltration. It was found that Lolium perenne and Medicago, which have well-developed roots, exhibited superior slope protection effects. These findings contribute to the theoretical understanding for the implementation of green ecological protection technology on soil slopes.

Distribution of soil microorganisms in different complex soil layers in Mu Us sandy land.

The soft rock in Mu Us Sandy Land has rich resources and high content of clay minerals. The combination of soft rock with sand can play a certain role in sand fixation and promote the green development of ecological environment. In this paper, the aeolian sandy soil in Mu Us Sandy was taken as the research object, and it was mixed with soft rock to form composite soil. The four volume ratios of soft rock to sand were respectively 0:1, 1:5, 1:2 and 1:1. And CK, P1, P2 and P3 were used to represent the above four volume ratios in turn. By means of quantitative fluorescent PCR and high throughput sequencing, 16S rRNA gene abundance and community structure were investigated. The results showed that the soil organic carbon (SOC) and total nitrogen (TN) contents in 0-30cm soil layer were higher. Compared with CK, the SOC of P2 was improved by 112.77% and that of P1 was 88.67%. The content of available phosphorus (AP) and available potassium (AK) was higher in 30-60cm soil layer, and P3 was more effective. The abundance of 16S rRNA gene in the mixed soil bacteria ranged from 0.03×109 to 0.21×109 copies g-1 dry soil, which was consistent with the changes of nutrients. Under different soil layers, the three dominant bacteria in the mixed soil were the same, namely Phylum Actinobacteriota, Phylum Proteobacteria and Phylum Chloroflexi, and there were more unique genera in each soil layer. Both bacteria ɑ and ß diversity showed that the community structure of P1 and P3 in 0-30cm soil layers was similar, and that of P1 and P2 in 30-60cm soil layers was similar. AK, SOC, AN (ammonium nitrogen), TN and NN (nitrate nitrogen) were the main factors contributing to the differentiation of microbial community structure under different compound ratios and soil layers, and Phylum Actinobacteria has the largest correlation with nutrients. The results showed that the soft rock could improve the quality of sandy soil, and that the growth of microbial growth was dependent on the soil physicochemical characteristics. The results of this study will be helpful to the study of the microscopical theory for the control of the wind-blown sand and the ecology of the desert.

Study on the effect, safety, prognosis quality and application value of extracorporeal shock wave based neural activity in carpal tunnel syndrome patients.

BACKGROUND: Mild to moderate CTS is the most common median nerve compression disease in middle-aged and elderly women, mainly manifested by hand numbness and pain. This paper analyzes the extracorporeal shock wave of patients with mild to moderate CTS after nerve mobilization. METHODS: The clinical data of 92 patients with CTS from June 2020 to June 2022 are analyzed and randomly divided into extracorporeal shock wave group (n = 47) and routine group (n = 45). The routine group undergoes nerve mobilization, and the extracorporeal shock wave group receives extracorporeal shock wave therapy on the basis of the routine group. The clinical efficacy, symptom improvement, pain score, median nerve electrophysiological examination results, upper limb symptom and function scores, and ADL scores before and after treatment are observed. The Spearman correlation coefficient is used to analyze the correlation between upper limb function and ADL score, and the incidence of complications after treatment is analyzed. RESULTS: The clinical efficacy, symptom improvement, pain score, median nerve electrophysiological examination results, upper limb symptom and function score, ADL score and the incidence of complications in the extracorporeal shock wave group are significantly better than those in the conventional group (P < 0.05). ADL scores are negatively correlated. CONCLUSION: Extracorporeal shock wave combined with nerve mobilization has a significant effect in the treatment of CTS patients, which can significantly improve the symptoms and pain scores of patients, and enhance the function of patients' upper limbs. At the same time, the incidence of complications in patients is less, and it has high safety.

Optical neural ordinary differential equations.

Increasing the layer number of on-chip photonic neural networks (PNNs) is essential to improve its model performance. However, the successive cascading of network hidden layers results in larger integrated photonic chip areas. To address this issue, we propose the optical neural ordinary differential equations (ON-ODEs) architecture that parameterizes the continuous dynamics of hidden layers with optical ODE solvers. The ON-ODE comprises the PNNs followed by the photonic integrator and optical feedback loop, which can be configured to represent residual neural networks (ResNets) and implement the function of recurrent neural networks with effectively reduced chip area occupancy. For the interference-based optoelectronic nonlinear hidden layer, the numerical experiments demonstrate that the single hidden layer ON-ODE can achieve approximately the same accuracy as the two-layer optical ResNets in image classification tasks. In addition, the ON-ODE improves the model classification accuracy for the diffraction-based all-optical linear hidden layer. The time-dependent dynamics property of ON-ODE is further applied for trajectory prediction with high accuracy.

Design and Research of an Underactuated Manipulator Based on the Metamorphic Mechanism.

Robot hands play an important role in the interaction between robots and the environment, and the precision and complexity of their tasks in work production are becoming higher and higher. However, because the traditional manipulator has too many driving components, complex control, and a lack of versatility, it is difficult to solve the contradiction between the degrees of freedom, weight, flexibility, and grasping ability. The existing manipulator has difficulty meeting the diversified requirements of a simple structure, a large grasping force, and the ability to automatically adapt to shape when grasping an object. To solve this problem, we designed a kind of underactuated manipulator with a simple structure and strong generality based on the metamorphic mechanism principle. First, the mechanism of the manipulator was designed on the basis of the metamorphic mechanism principle, and a kinematics analysis was carried out. Then, the genetic algorithm was used to optimize the size parameters of the manipulator finger structure. Finally, for different shapes of objects, the design of the control circuit binding force feedback control was carried out with a grasping experiment. The experimental results show that the manipulator has simple control and can grasp objects of different sizes, positions, and shapes.

Effects of soft rock on soil properties and bacterial community in Mu Us Sandy Land, China.

Soft rock is a new material that could be used for the improvement of Mu Us Sandy Land, China. It can be utilized for wind prevention and sand fixation, both of which are of great importance to ecological restoration aims and cultivated land replenishment in desert areas. Four treatments with different compound ratios of soft rock and sand-0:1 (CK), 1:5 (P1), 1:2 (P2), and 1:1 (P3)-were studied. Fluorescence quantitative PCR (qPCR) and high-throughput sequencing were used to analyze the structure and diversity of the bacterial community in the compound soil and its relationship with physical and chemical parameters in the soil. The results showed that in comparison to CK treatment, soil organic carbon (SOC), total nitrogen (TN), and NH4 +-N increased significantly in the P1 treatment; available phosphorus (AP), available potassium (AK), and NO3 --N increased significantly in the P3 treatment. The bacterial gene copy number with P3 treatment was highest, showing a significant increase of 182.05% compared with the CK treatment. The three bacterial groups with the highest relative abundance at the phylum level were Actinobacteria, Proteobacteria, and Chloroflexi, accounting for more than 70% of the total population. The bacterial α diversity showed the same trend, the diversity and abundance indices of the P1 and P3 treatments were the highest, and the ß diversity showed that the community structure of the two groups in these treatments were similar. norank_f__Roseiflexaceae and Gaiella (belonging to Actinobacteria) significantly differed with differing compound ratios in each treatment. NO3 --N, NH4 +-N and SOC were the main factors affecting bacterial community structure, and had a significant positive correlation with Gaiella abundance. These species are known to play an important role in stabilizing the soil structure of sandy land. Overall, 1:5 and 1:1 compound soil mixtures were beneficial towards the microbial community of sandy land, which plays an important role in biological sand fixation. This study provides an important theoretical basis for the supplementation of arable land area and the improvement of sandy land productivity, and has a good promotion prospect.

High-resolution electron time-of-flight spectrometers for angle-resolved measurements at the SQS Instrument at the European XFEL.

A set of electron time-of-flight spectrometers for high-resolution angle-resolved spectroscopy was developed for the Small Quantum Systems (SQS) instrument at the SASE3 soft X-ray branch of the European XFEL. The resolving power of this spectrometer design is demonstrated to exceed 10 000 (E/ΔE), using the well known Ne 1s-13p resonant Auger spectrum measured at a photon energy of 867.11 eV at a third-generation synchrotron radiation source. At the European XFEL, a width of ∼0.5 eV full width at half-maximum for a kinetic energy of 800 eV was demonstrated. It is expected that this linewidth can be reached over a broad range of kinetic energies. An array of these spectrometers, with different angular orientations, is tailored for the Atomic-like Quantum Systems endstation for high-resolution angle-resolved spectroscopy of gaseous samples.

Ensemble streamflow forecasting based on variational mode decomposition and long short term memory.

Reliable and accurate streamflow forecasting plays a vital role in the optimal management of water resources. To improve the stability and accuracy of streamflow forecasting, a hybrid decomposition-ensemble model named VMD-LSTM-GBRT, which is sensitive to sampling, noise and long historical changes of streamflow, was established. The variational mode decomposition (VMD) algorithm was first applied to extract features, which were then learned by several long short-term memory (LSTM) networks. Simultaneously, an ensemble tree, a gradient boosting tree for regression (GBRT), was trained to model the relationships between the extracted features and the original streamflow. The outputs of these LSTMs were finally reconstructed by the GBRT model to obtain the forecasting streamflow results. A historical daily streamflow series (from 1/1/1997 to 31/12/2014) for Yangxian station, Han River, China, was investigated by the proposed model. VMD-LSTM-GBRT was compared with respect to three aspects: (1) feature extraction algorithm; ensemble empirical mode decomposition (EEMD) was used. (2) Feature learning techniques; deep neural networks (DNNs) and support vector machines for regression (SVRs) were exploited. (3) Ensemble strategy; the summation strategy was used. The results indicate that the VMD-LSTM-GBRT model overwhelms all other peer models in terms of the root mean square error (RMSE = 36.3692), determination coefficient (R2 = 0.9890), mean absolute error (MAE = 9.5246) and peak percentage threshold statistics (PPTS(5) = 0.0391%). The addressed approach based on the memory of long historical changes with deep feature representations had good stability and high prediction precision.

To evaluate the serum cortisol, salivary cortisol, and serum interleukin-1 B level in patients of chronic periodontitis with smoking and stress and without smoking and stress.

ABSTRACT: The role of cognitive, social and biological factors in the etiology of chronic periodontitis has been reported.The aim of this study was to evaluate the salivary cortisol level and interleukin-1 B level in patients of Chronic periodontitis in smokers and stress and nonsmokers without stress.The design of study randomized, prospective, double-blinded, and prospective study.The total sample size was comprised of 600 subjects between the ages of 20 and 50 years. The sample size was divided into 300 males and 300 females. Out of 600 subjects, 200 subjects comprised of subjects with chronic periodontitis with positive depression level with a history of smoking (Group I), 200 subjects comprised of subjects with chronic periodontitis without depression and without smoking (Group II), and 200 subjects who were taken as the control group comprised of healthy subjects without chronic periodontitis, without depression level, and no smoking history (Group III). Salivary cortisol levels were determined by enzyme-linked immunosorbent assay (ELISA).The result showed that there was a positive correlation between morning and evening salivary cortisol level in all the groups with correlation coefficient. There was significant higher value of salivary cortisol in Group I patients when compared with Group II and Group III. However, when the comparison of salivary cortisol levels was done between the Group II and Control group, the result showed nonsignificant P value.It is suggested that stress is positively correlated with the salivary cortisol levels in smokers and nonsmokers.

Formulation of traditional Chinese medicine and its application on intestinal flora of constipated rats.

In this study, the self-extracted constipation treatment of traditional Chinese medicine extracts was applied to constipated rats. To explore the mechanism and role of the Chinese medicine for the treatment of constipation, the 16S rRNA sequencing and qRT-PCR technology were used to analyze the intestinal flora. We found that the relative abundance of Firmicutes with constipation was significantly higher accounted for 86.7%, while the gut microbiota was significantly changed after taking a certain dose of Chinese medicine, greatly increased the relative abundance of Lactobacillus accounted for 23.1%, enhanced the symbiotic relationships of Lactobacillus with other intestinal flora. The total copies of intestinal bacteria in the constipated rats decreased after taking the traditional Chinese medicine. Finally, this study results provides a theoretical basis for the treatment and understand the mechanism and effect of traditional Chinese medicine on rate constipation.

Analysis of water and nitrogen use efficiency for maize (Zea mays L.) grown on soft rock and sand compound soil.

BACKGROUND: Maize was grown on compound soils constituted from mixtures of soft rock and sand at different ratios, and water use efficiency (WUE), nitrogen use efficiency (NUE) and fertilizer nitrogen use efficiency (FNUE) were quantified. The data were used to assist in designing strategies for optimizing water and nitrogen management practices for maize on the substrates used. Maize was sown in composite soil prepared at three ratios of soft rock and sand (1:1, 1:2 and 1:5 v/v) in Mu Us Sandy Land, Yuyang district, Yulin city, China. Yields, amount of drainage, nitrogen (N) leaching, WUE and NUE were calculated. Then a water and nitrogen management model (WNMM) was calibrated and validated. RESULTS: No significant difference in evapotranspiration of maize was found among compound soils with soft rock/sand ratios of 1:1, 1:2 and 1:5, while water drainage increased significantly with increasing soft rock/sand ratio. WUE increased to 1.30 kg m-3 in compound soil with 1:2 soft rock/sand ratio. Nitrogen leaching and ammonia volatilization were the main reason for nitrogen loss, and N reduction mainly relied on crop uptake. NUE and FNUE could reach 33.1 and 24.9 kg kg-1 N respectively. Water drainage and nitrogen leaching occurred mostly during heavy rainfall or irrigation. Through a scenario analysis of different rainfall types, water and fertilizer management systems were formulated each year. CONCLUSION: This study shows that soft rock plays a key role in improving the WUE, NUE and FNUE of maize. © 2016 Society of Chemical Industry.

Mutation in the caveolin-3 gene causes asymmetrical distal myopathy.

Mutations in the gene encoding caveolin-3 (CAV3) can cause a broad spectrum of clinical phenotypes, including limb girdle muscular dystrophy, rippling muscle disease, distal myopathy (MD), idiopathic persistent elevation of serum creatine kinase and cardiomyopathy. MD is a relatively rare subtype of caveolinopathy. Here, we report a sporadic case of a middle-aged female Chinese patient with MD in which a CAV3 mutation was identical to that previously reported in cases of rippling muscle disease. T1-weighted enhanced skeletal muscle MRI of the lower limbs showed an abnormal signal in the distal and proximal muscles. A muscle biopsy revealed moderate dystrophic changes, and immunohistochemical staining showed reduced CAV-3 expression in the plasmalemma. Genetic analysis revealed a heterozygous c.136G > A (p.Ala46Thr) CAV3 mutation that appeared to be de novo because it was absent from the patient's parents. This study suggested that the CAV3 c.136G > A (p.Ala46Thr) mutation can cause MD as well as different phenotypes in different individuals, suggesting that additional unknown loci must affect the disease phenotypes.

Bioremoval and recovery of Cd(II) by Pseudoalteromonas sp. SCSE709-6: Comparative study on growing and grown cells.

Comparison of the bioremoval and recovery of Cd(II) by growing and grown marine bacterium Pseudoalteromonas sp. SCSE709-6 was performed in batch systems. Bioremoval with growing cells (Sorption I) showed better performance at low Cd(II) concentrations, whereas bioremoval with grown cells (Sorption II) had significant advantages in both removal efficiency and time consumption at high Cd(II) concentrations. The optimal pH was higher for Sorption I than for Sorption II for achieving the maximum Cd(II) removal efficiency. Complete desorption was achieved using either Na2EDTA or HNO3 as eluent. Cd(II) adsorbed on grown cells had higher tendency to be desorbed. Na2EDTA was a preferable eluent for the recycling biomaterials, whereas HNO3 performed better for the final security disposal of sludge. For Sorption II, both Langmuir and Freundlich isotherms well explained the biosorption behavior, and the pseudo-second-order model better expressed biosorption and desorption kinetics.

Bio-removal of cadmium by growing deep-sea bacterium Pseudoalteromonas sp. SCSE709-6.

Effective bio-removal of heavy metals is important for water treatment. Although a number of microorganism species demonstrated the ability of living cells to remove cadmium, most of them were tested at fixed concentration of metals, salinity, and temperature. This paper reported a research on the screening and performance of a newly developed deep-sea bacterium, Pseudoalteromonas sp. SCSE709-6, for Cd(II) removal by growing cells under a range of experimental conditions: 0-50 mg/L of Cd(II), 15-30 °C of incubation temperatures, 6.5-8.0 of initial pH, and 1.5-5.0 % of salinity. Study results revealed that Pseudoalteromonas sp. SCSE709-6 could remove more than 96 % of Cd(II) on growth. The Cd(II) bioremoval was in correlation but not in accordance with biomass. As cadmium concentrations increased, the Cd(II) removal by cell adsorption played an increasingly important role compared with that of intracellular accumulation. For the removal mechanism, Fourier transform infrared spectroscopy revealed that carboxyl, amido and hydroxyl of saccharides, and proteins in the extracellular polymeric substances are the most active groups for Cd(II) absorption. The bacterium reported in this study offers a new microbe strain for Cd(II) bioremediation.

[FTIR spectrum and detoxication of extracellular polymeric substances secreted by microorganism].

In order to explore the effect of extracelluar polymeric substances (EPS) on resistance and removal of heavy metals, the production of EPS, secreted by cadmium-resistant strain (SCSE425-7) and cadmium-removal strain (SCSE709-6) was investigated combined with Fourier transform infrared spectroscopy (FTIR). The results showed that the high resistance to cadmium of strain SCSE425-7 was related to the high production of soluble EPS, whereas SCSE709-6 secreted more insoluble EPS resulting in better cadmium removal performance. It was indicated that soluble extracellular carbohydrates may help the bacteria to enhance resistance to Cd2+, and insoluble EPS could contribute to Cd2+ removal effectively. The FTIR spectra showed that the peaks of amide and carboxyl were main functional groups for Cd2+ adsorption.

[Dynamic characteristics of forest landscape in Chengdu City in last 20 years].

Based on the remote sensing data of Landsat TM (1985, 1995, and 2000) and CBERS (2006), and by using landscape pattern method and index model of regional land use change in combining with eco-function regionalization, this paper analyzed the dynamic characteristics of forest landscape in Chengdu City in 1985-2006. In the study period, over 17,000 hm2 of forest land lost, and the number and area of small- and medium-size patches changed significantly, indicating the apparent conversion and fragmentation of forest land. Forest land was mainly distributed in mountainous area, accounting for 70% of the total. In contrast, more number of patches was found in plain region, amounting to 70% of the total. The most rapid change of forest land area occurred in 1985-1995, especially in mountainous region. The relative change rate of forest land area in different eco-function regions also varied in different periods. Forest land, converted to or converted from, was mainly related to cropland and grassland. In 2000-2006, forest land was quite stable. Survival-oriented economic welfare, environmental security, and fast urbanization process were the main driving forces of the temporal dynamic change of forest landscape, whereas geographical division and socio-economic layout were the main constraints to the spatial dynamic change of forest landscape.

Clinical and experimental pathology of Moyamoya disease.

OBJECTIVE: To investigate the etiology, pathology, and mechanism of pathogenesis of Moyamoya disease. METHODS: A total of 15 human autopsies were analyzed. In addition, in order to create an animal model of the disease, 21 Japanese rabbits were divided randomly into two groups and subjected to injections of horse serum either intravenously or locally in the area of the sympathetic ganglia. Pathological and immunohistochemical characteristics were observed. RESULTS: The pathological features of the autopsies and the animal models both involved intima hyperplasia and stenosis or even occlusion of the lumen in the terminal ends of the internal carotid artery and the anterior and middle cerebral arteries. Disconnections or even breakages of the inner layer of the lumen were also observed, without an obvious inflammatory response. Hyperplasic smooth muscle cells of the medial membrane had extended inward through broken portions of the internal elastic lamina, with intima cell hyperplasia resulting in lumen stenosis. The hyperplastic vascular walls were positive for IgG and IgM. CONCLUSIONS: The etiology of Moyamoya disease may involve allergic angiitis. A possible mechanism is that proximal portions of the circle of Willis first develop chronic stenosis or occlusion, leading to compensatory small vessel proliferation, which perforates into the cerebral parenchyma.