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The rapid detection of grid voltage faults is crucial to achieve grid voltage fault ride-through. However, conventional grid voltage detection methods, including Fourier transform, dq axis transform, wavelet transform, and voltage peak methods, generally yield varying degrees of distortions in the detection results of short-time disturbances in grid voltage. To address this, this paper proposes an approach for quickly detecting short-time disturbances in grid voltage. Leveraging the distinctive high harmonic content present in grids, the suggested strategy involves a transformation of grid voltage calculated using the Fourier transform method, known for its robust anti-interference performance, into high-frequency signals through coordinate conversion. The integration of the rolling sliding window method addresses the extended calculation time issue associated with the Fourier transform, enabling the detection of grid voltage disturbance signals within a single high-frequency signal cycle using this method. The simulation experiment results demonstrated the wide applicability of the proposed method compared with other methods. It is not only effective for short-time grid voltage disturbances, but also suitable for long-time grid voltage disturbances. Regardless of whether high-frequency harmonics are present or absent in the grid voltage, this method allows for the rapid detection of grid voltage disturbances (within about 2 ms). Moreover, its accuracy in detecting grid voltage amplitudes aligns with requirements in engineering applications.

In the operating environment of power system with weak grid characteristics, the traditional current source converter control mode is prone to vibration, which increases the crossing difficulty and off-grid probability of wind turbines. Based on virtual synchronous generator (VSG) technology, a novel control strategy of voltage source converter is designed in this paper, and the voltage source converter control mode and current source converter control mode are studied. Under normal grid-connected operation conditions, voltage source converter control mode is adopted. Active power control increases active power compensation through VSG, and reactive current is injected into the front end of reactive power control. Under start-stop and high & low-voltage ride-through conditions, the current source converter control mode is adopted. The control strategy combines the advantages of voltage source converter control mode and the current source converter control mode. It has not only the frequency support characteristics, but also the fast active and reactive power response capability. The simulation and prototype experiments on the grid-connection process, active and reactive power response and high & low-voltage ride-through process of the full-power wind power converter are carried out. The results show that the proposed control scheme can achieve good control effect under each operating condition of the wind power converter, so that the wind power units have good steady-state and dynamic performance, and can well adapt to the demands of new energy grid-connection.

Due to the increase of network equipments and the uncertainty of the transmission environment, the message delay is also uncertain, and the asynchronous consensus protocol possesses more advantages. Miller et al proposed the first asynchronous consensus protocol HoneyBadgerBFT in 2016, but its transmission efficiency can be optimized furthermore while achieving high throughput. The broadcast protocol in HoneyBadgerBFT was improved by reducing the message complexity in the broadcast process, and adding optional message request process to achieve rapid response and efficient transmission.

Background and objective It has been proven that the development and biological behavior of lung carcinoma is affected by a number of signaling pathway elements. The expression levels of Krüppel-like factor 4 (KLF4) and secreted protein acidic and rich in cysteine (SPARC) were correlated with tumorigenesis and prognosis. This study aims to investigate KLF4 and SPARC expression and their correlation with the clinical characteristics of non-small cell lung cancer (NSCLC). Methods KLF4 and SPARC expression was examined immunohistochemically in NSCLC and normal lung tissues from 89 patients. Results SPARC expression was increased in the tumor specimens compared with the control tissue (70.8% vs 7.9%, P0.05). KLF4 expression was negatively correlated with SPARC expression in NSCLC (r=-0.245, P

We investigated the responses of leaf and individual traits, growth, and fluorescence characteristics of seedlings of two dominant species of broad-leaved Korean pine forest in Changbai Mountain, i.e., Pinus koraiensis and Quercus mongolica, to five spectrum-attenuation treatments. Results showed that the architecture and growth of P. koraiensis and Q. mongolica seedlings were mainly regulated by ultraviolet B (UV-B) radiation and blue light. The attenuation of blue light significantly decreased leaf area ratio and relative growth rate of two species. The attenuation of UV-B radiation significantly increased leaf area ratio and relative growth rate of P. koraiensis seedlings by 41.8% and 47.7%, respectively, and significantly decreased plant height, total leaf area, and biomass accumulation of Q. mongolica seedlings. Furthermore, the attenuation of UV-B radiation significantly decreased the fluorescence regulation ability of two tree seedlings, with lower magnitude of P. koraiensis than Q. mongolica. The non-regulatory quantum yield (ΦNO) of P. koraiensis increased by 31.6%, and the ΦNPQ/ΦNO ratio, an indicator for photosynthetic fluorescence regulation ability, decreased by 37.5%. These results suggested that those two species might have evolved adaptation strategies to changes in canopy spectral compositions of their respective habitats. Q. mongolica seedlings tended to improve light capture ability through rapid morphological responses, while P. koraiensis seedlings preferred to increase carbon assimilation efficiency by adjusting fluorescence characteristics. [ABSTRACT FROM AUTHOR]

Objective To study anxiety and depression in Chinese patients with cystic fibrosis (CF). Methods Clinical data from 28 CF patients in the cystic fibrosis registry study of Peking Union Medical College Hospital were collected and analyzed. Hospital anxiety and depression scale was used to identify anxiety and depression. Results The cohort had 42.9% (12/28) males with a mean age of 23±4.8 years. 14 patients (50%) had anxiety or depression. Among them, 8 subjects (28.6%) had moderate and severe anxiety or depression, and 5 patients (17.9%) were with moderate and severe anxiety, and 7 patients(25%) with moderate and severe depression. One patient(3.6%) had severe anxiety, no patients with severe depression, and four patients (14.3%) had both moderate and severe anxiety and depression. Compared to patients without anxiety or depression, patients with anxiety had significantly lower FVC% pred (54.5%±18.8% with anxiety, 80.0%±14.6% without anxiety or depression, P＜0.05), and patients with depression had significantly lower FEV1% pred (41.6%±21.6% with depression, 64.2%±20.9% without anxiety or depression, P＜0.05) and FVC% pred (53.9%±21.0% with depression, 80.0%±14.6% without anxiety or depression, P＜0.01). Conclusions Half of CF patients have anxiety or depression, with a high comorbidity rate of anxiety and depression and a low prevalence of severe anxiety or depression in our cohort. CF patients with anxiety or depression have worse pulmonary ventilationy function compared to CF patients without anxiety or depression.

Li-doped (Ba0.85Ca0.15) (Ti0.9Zr0.1) O3 (BCTZL-x) lead-free piezoceramics have been prepared by the conventional ceramic process. The influence of a Li+-containing additive on the crystal phase, microstructure and electric properties of (Ba0.85Ca0.15) (Ti0.9Zr0.1) O3 ceramics were systematically investigated through all kinds of measurement, such as X-ray diffraction(XRD) and SEM. The X-ray results show that the BCTZL-x ceramics sintered at 1 400 °C/2 h had pure ABO3 perovskite structure. The BCTZL-x ceramics went through the phase transition from O phase to T phase with Li+ doping increasing. The ceramics became dense when x≥0.3. Additionally, BCTZL-0.3 ceramics showed an excellent performance: d33 = 456 pC/N, kp = 0.49, εr = 4 864, tanδ = 0.018, Qm = 130. [ABSTRACT FROM AUTHOR]

The five main forest types, i. e. larch forest, birch forest, coniferous mixed forest, broad-leaved mixed forest, and coniferous and broadleaved mixed forest, with varied age classes (young, mid-agedv, pre-mature, and over mature) were selected to investigate the variation of soil organic carbon density in the forest region of Northeast China. Results showed that both soil organic carbon content and density were relatively larger in the top soil layer across the five forest types, decreased gradually with soil depth, and varied insignificantly with either forest type or forest age class. The forest soil carbon density was concentrated in the top 20 cm of soil which accounted for 84. 7% - 86-1%, 51. 7% -59. 8% and 51. 2% -53. 4% of total soil carbon density in the Daxing' an, Xiaoxing' an and Changbai mountains, respectively. The total soil organic carbon density decreased significantly with increasing latitude, which might be attributed mainly to the thickness of soil layers in forest region of Northeast China. [ABSTRACT FROM AUTHOR]

Aiming at the shortcomings of traditional PID control method, such as parameter perturbation and poor anti-jamming ability of double-rotor permanent magnet synchronous motor, a single neuron fuzzy PID control method is proposed. Firstly, a mathematical model of double-rotor permanent magnet synchronous motor is established, and a single neuron fuzzy PID controller is designed. And then the system is designed and simulated by MATLAB. Finally, the simulation results of traditional PID and single neuron fuzzy PID control are compared and analyzed.The simulation results show that the single neuron fuzzy PID control can improve the robustness of the system effectively, so that the double rotor permanent magnet synchronous motor control system has better dynamic and static performance and anti-interference ability.

A sampling plot investigation was conducted to study the soil organic carbon (SOC) storage in 0-40 cm layer in 10-, 15-, 26-and 61 years old Larix gmelinii plantations in Great Xing'an Mountains of Northeast China as well as the temporal variation pattern of the SOC source/ sink during the plantation management after the clear cutting of primary L. gmelinii forest. With the increasing age of the plantations, the SOC storage increased after an initial decrease, and the inflection point was at a stand age between 15-and 26-years old. Compared with that of primary forest, the SOC storage of the plantations played a role of carbon source at early stage (10-26 years old), but gradually transformed into carbon sink then, with a SOC storage of 158. 91 t · hm-2 in 61-year-old plantation. The SOC storage of the plantations increased with soil depth initially, but was higher in upper soil layer than in deeper soil layer after the stand age being 26, which implied that human disturbance had strong effects on the vertical distribution of SOC. It was considered that the appropriate cutting age for the L. gmelinii plantations in Great Xing'an Mountains could be at least 60 years old. [ABSTRACT FROM AUTHOR]

Taking Betula ermanii forests distributed at the altitudes 1800-2050 m on the northern slope of Changbai Mountains as test objects, and using leaf carbon isotope content (&dgr;13C) as an indicator of B. ermanii water use efficiency (WUE), this paper studied the effects of altitudinal gra? dient on the WUE of B. ermanii forests in the area. With the increase of altitude, the soil volumetric water content (VMC) and the leaf mass per area (LMA) of B. ermanii increased significantly, while the leaf water content (LWC) and soil temperature were in adverse. There was a significant positive correlation between leaf &dgr;13 C and altitude, with the increment of leaf &dgr;13 C being 1.013 %·(100 m)-1, and the leaf &dgr;13C was positively correlated with soil VWC and LMA but negatively correlated with soil temperature and LWC. Temperature was not the sole limiting factor for the dis tribution of treeline in Changbai Mountains, whereas the physiological drought of B. ermanii during its growing season caused by the different water and heat conditions and their interactions along the altitudinal gradient could be the other limiting factors. [ABSTRACT FROM AUTHOR]

Global climate change is one of the most concerned environmental problems in the world since the 1980s, giving significant effects on the plant productivity and the water transport and use patterns. These effects would be reflected in the water use efficiency (WUE) of individual plants, communities, and ecosystems, and ultimately, in the vegetation distribution pattern, species composition, and ecosystem structure. To study the WUE of plants would help to the understanding and forecasting of the responses of terrestrial vegetation to global climate change, and to the adoption of adaptive strategies. This paper introduced the concept of plant WUE and the corresponding measurement techniques at the scales of leaf, individual plant, community, and ecosystem, and reviewed the research progress in the effects of important climatic factors such as elevated atmospheric CO2 concentration, precipitation pattern, nitrogen deposition, and their combination on the plant WUE, as well as the variation characteristics of plant WUE and the adaptive survival strategies of plants under different site conditions. Some problems related to plant WUE research were pointed out, and the future research directions in the context of global climate change were prospected. [ABSTRACT FROM AUTHOR]

The degeneration of karst ecosystem is closely associated with the reduction of soil nutrients and fine root biomass, and the retention of soil nutrients is of significance in sustaining ecosystem functioning. To understand the changes in the fine root biomass and soil nutrient retention in degenerated karst ecosystems, a comparative study was conducted with three typical vegetation stands (forest, shrub, and shrub-grass) in Central Guizhou of Southwest China. Soil samples with fine roots were collected from the depths 0-5 cm, 5-10 cm, and 10-15 cm, with the related indices of fine roots and nutrients measured. In the three stands, fine roots dominantly distributed in 0 -10 cm soil layer, and decreased sharply with soil depth. The living fine root biomass in 0-10 cm soil layer under forest, shrub, and shrub-grass occupied 83. 36% , 86. 91% , and 93. 79% of the total fine root biomass, and 42. 78% , 56. 75% , and 53. 38% of the total living fine root biomass within the 0-15 cm soil layer, respectively. The fine root biomass of predominant plant species varied with vegetation types. The N and P storage of the living fine roots in 0-5 cm soil layer under forest stand was significantly higher than those under shrub stand and shrub-grass stand, and no significant differences were observed between the latter two stands. However, the N and P storage of the living fine roots in 5-10 cm soil layer under different stands decreased in the order of forest > shrub > shrub-grass (P<0. 05). There was a significant positive correlation between the plant aboveground biomass and the living fine root biomass in 0-10 cm soil layer, and a significant negative correlation between the N and P contents of plant leaves and the specific length of living fine roots, illustrating that the nutrient uptake and retention by the living fine roots could have particular importance in the aboveground biomass establishment and ecosystem functioning. [ABSTRACT FROM AUTHOR]

A finite element analysis basing on transfer matrix method of multibody system for the parachute packing machine was finished in this article. After the research of multi-point cloud with the stress and displacement of the whole structure,considering the stress and deformation of the organization,the parachute packing machine has been optimized. It also has been verified by test that: the optimization has improved the working strength of the parachute packing machine,and the requirements of long time working at full capacity can be reached.

The occurrence and development of gastric cancer (GC) is determined by many factors. In recent years, the development of molecular biology has provided new ideas for the diagnosis and treatment of GC. Microsatellite instability (MSI) GC is a special type of GC caused by the body 's DNA mismatch repair (MMR) gene defect. Studies of the clinical characteristics, molecular mechanisms and prognosis of MSI GC found specific clinicopathological features and better prognosis in MSI GC compared with ordinary types of GC. However, there are still some controversies in the study of MSI gastric cancer at home and abroad. This article aims to review the concept of MSI, the relationship between MSI and clinicopathological features of gastric cancer, and the treatment progress of MSI gastric cancer.

Aiming at the problem of corrosion detection of buried gathering and transportation pipeline under trenchless conditions，a selfleakage magnetic field model for corrosion defects of buried gathering and transportation pipeline was established based on the magnetic dipole model and considering the magnetic charge distribution of corrosion defects.The waveform characteristics of magnetic induction intensity of corrosion defects and the effects of different height off the ground and size of corrosion defects on the magnetic induction intensity were studied by numerical simulation.Results showed that at the corrosion defect，Bx and Bz presented extreme value characteristics and the direction was opposite，By had the feature of passing zero and the peak value changed the direction；the height off the ground was inversely proportional to the extreme values of Bx and Bz and the peak values of By；the size of corrosion defect was proportional to the extreme values of Bx and Bz and the peak value of By.According to the oilfield field testing data，14 excavation points were selected to verify the distribution characteristics of magnetic induction intensity of corrosion defects，and 3 excavation points were selected to verify the relationship between the height off ground and the size of corrosion defects and magnetic induction intensity.

Objective To evaluate the safety and efficacy of transurethral retrograde en-bloc excavation of bladder tumor （EEBT） after basal injection with sterile water for non-muscular invasive bladder cancer （NMIBC）. Methods Clinical data of 60 patients with NMIBC were analyzed retrospectively. All patients were divided into two groups according to the surgical procedure. In the EEBT group, 30 patients received transurethral EEBT after basal injection with sterile water, and 30 patients underwent conventional transurethral resection of bladder tumor （TURBT） in the TURBT group. The baseline data, perioperative parameters, postoperative tumor pathological stage and the pathologists’ degree of satisfaction with the specimen were compared between two groups. All patients received follow-up. The tumor recurrence rate was statistically compared between two groups. Results There was no significant difference in gender, age, tumor size, tumor location, proportion of single and multiple tumors and preoperative complications between two groups （all P > 0.05）. No statistical significance was also observed in the bladder perforation rate, postoperative tumor pathological stage and pathological T stage between EEBT group and TURBT group（all P > 0.05）. Compared with the TURBT group, the operation time was longer, whereas intraoperative blood loss was less, the incidence of obturator reflex was lower, postoperative indwelling catheter time and the length of hospital stay were shorter, the pathologists’ degree of satisfaction with the specimen was higher, and the one-year tumor recurrence rate was lower in the EEBT group （all P < 0.05）. Conclusion Compared with TURBT, transurethral retrograde EEBT after basal injection with sterile water has multiple advantages of less intraoperative blood loss, faster postoperative recovery, intact tumor specimen and lower one-year tumor recurrence rate in the treatment of NMIBC.

Objective To compare hepatic artery infusion chemotherapy (HAIC) with transcatheter arterial chemoembolization (TACE) in the treatment of hepatocellular carcinoma combined with both anti-angiogenesis and immunotherapy for effectiveness and safety. Methods Ninety-three patients with hepatocellular carcinoma including stage B 18 cases and stage C 75 cases, and 74 males, 19 females with a median age of 57 (27-78) in Tianjin Medical University Cancer Hospital from January 2019 to December 2020 were studied retrospectively. In the treatment combined with anti-angiogenesis and immunotherapy, 50 cases received TACE and 43 cases received HAIC. Response Evaluation Criteria in Solid Tumors (RECIST) Version 1.1 was used to evaluate the efficacy of treatment. The primary endpoints were both objective response rate (ORR) and disease control rate (DCR), and the secondary endpoints both median progression free survival (mPFS) and median overall survival (mOS). Results Both ORR (72.09% vs. 44.00%, P=0.006) and DCR (88.37% vs. 60.00%, P=0.002) were significantly more in HAIC group than in TACE group. The median follow-up duration was 12.13 months in HAIC group and 11.95 months in TACE group. mPFS in TACE group was 11.83 months (95%CI: 4.36-19.31 months) with mOS 17.93 months (95%CI: 11.80-24.06 months). Both mPFS and mOS did not reach in HAIC group. There were significant differences in PFS and OS between two groups (P=0.017; P=0.007). Conclusions The patients with advanced hepatocellular carcinoma would benefit from HAIC combined with both anti-angiogenesis and immunotherapy in disease control and survival with less side effects and better safety when compared with TACE combination treatment.

Objective To discuss the application value of diatom examination in lung tissue for the forensic diagnosis of drowning. Methods The experimental animals were divided randomly into drowning, postmortem submergence and dying on land group. Diatoms in lung tissue and drowning fluid were analyzed quantitatively by microwave digestion-vacuum filtration-automated scanning electron microscopy diatom examination method. The ratios of content of diatoms in lung tissue and drowning fluid （CL/CD ratio） were recorded. Results The CL/CD ratios of experimental rabbits in the drowning group （5.82±3.50） were much higher than that of postmortem submergence group （0.47±0.35）; the CL/CD ratios of different parts of the lung lobes of experimental pigs in the drowning group were higher than that of postmortem submergence group （P1.6 were from drowning group. Conclusion CL/CD ratio is an indicator with good application prospects in the diagnosis of drowning.

Objective To investigate the clinical characteristics of meningeal carcinomatosis with nervous system syndrome as initial symptom. Methods Clinical data, laboratory and imageing examinations were retrospectively analyzed in 23 patients of meningeal carcinomatosis from June 2009 to December 2017. Results Twenty patients (86.96%) had headache as initial symptom and 12 (52.17%) had headache with vomiting. Head enhanced MRI showed obvious enhancement in meningeal lesions,and 13 cases (59.09%) had meningeal enhancement with enlargement of ventricular system; CT showed enlargement of supratentorial ventricular system (1 case). About 65.22% (15/23) primary lesions were originated from lungcancer,and others were or iginated from colon cancer,hematological lymphoma,gastric cancer, spinal astrocytoma (4.35%, 1/23 respectively), and some unknown origin (17.39%, 4/23). About 82.61% (19/23) patients cerebrospinal fluid pressure increased obviously, Tumor markers especially carcinoembryonic antigen (CEA) were mostly increased in serum (11/17) and cerebrospinal fluid (7/10). Conclusions Headache and vomiting are the most common clinical symptoms of meningeal carcinomatosis. Enhanced MRI shows meningeal enhancement or communicating hydrocephalus. Cerebrospinal fluid pressure tends to increase significantly. Carcinoembryonic antigen is significantly increased in serum and cerebrospinal fluid. Primary lesions of meningeal carcinomatosis mostly originate fromlungcancer. Finding tumor cells in cerebrospinal fluid is the" golden standard" of diagnosis.

Objective To investigate the morphological changes in the degeneration and regeneration of neuromuscular junctions （NMJ） during the repair of mouse skeletal muscle contusion and discuss the correlation between the degeneration and regeneration of NMJ and wound age. Methods A total of 50 healthy adult male mice were randomly divided into 10 groups, including 9 experimental groups and 1 control group. Immunofluorescent staining was applied, and neurofilament was marked with neurofilament protein-H （NF-H）, presynaptic membrane was marked with synaptophysin （Syn）, presynaptic membrane was marked with acetylcholine receptor （AChR）. Morphological changes of NMJ regeneration at different time points after mouse skeletal muscle contusion were detected. Results The neurofilament and presynaptic membrane of NMJ at the junction of contusion zones began to degrade after contusion, and completed degradation at about 3 d post-injury. Then they gradually regenerated, roughly completing the regeneration at about 21 d and basically reaching the control group level. The ratio of presynaptic membrane quantity to presynaptic membrane quantity showed a trend of decreasing then rising and finally reaching the control level. Conclusion During the repair of mouse skeletal muscle contusion, the morphological changes and wound age of the NMJ at the junction of contusion zones have a close correlation, which is expected to be one of the biological indicators for forensic skeletal muscle wound age estimation.

We investigated the responses of leaf and individual traits, growth, and fluorescence characteristics of seedlings of two dominant species of broad-leaved Korean pine forest in Changbai Mountain, i.e ., Pinus koraiensis and Quercus mongolica , to five spectrum-attenuation treatments. Results showed that the architecture and growth of P. koraiensis and Q. mongolica seedlings were mainly regulated by ultraviolet B (UV-B) radiation and blue light. The attenuation of blue light significantly decreased leaf area ratio and relative growth rate of two species. The attenuation of UV-B radiation significantly increased leaf area ratio and relative growth rate of P. koraiensis seedlings by 41.8% and 47.7%, respectively, and significantly decreased plant height, total leaf area, and biomass accumulation of Q. mongolica seedlings. Furthermore, the attenuation of UV-B radiation significantly decreased the fluorescence regulation ability of two tree seedlings, with lower magnitude of P. koraiensis than Q. mongolica . The non-regulatory quantum yield ( Φ NO ) of P. koraiensis increased by 31.6%, and the Φ NPQ / Φ NO ratio, an indicator for photosynthetic fluorescence regulation ability, decreased by 37.5%. These results suggested that those two species might have evolved adaptation strategies to changes in canopy spectral compositions of their respective habitats. Q. mongolica seedlings tended to improve light capture ability through rapid morphological responses, while P. koraiensis seedlings preferred to increase carbon assimilation efficiency by adjusting fluorescence characteristics.

This study aimed to investigate whether psoralen can aggravate hepatotoxicity induced by carbon tetrachloride(CCl&#95;4) by inducing hepatocyte cycle arrest and delaying liver regeneration. Female C57 BL/6 mice aged 6-8 weeks were randomly divided into control group, model group(CCl&#95;4 group), combined group(CCl&#95;4+PSO group) and psoralen group(PSO group). CCl&#95;4 group and CCl&#95;4+PSO group were given CCl&#95;4 intraperitoneally at a dose of 100 μL·kg~(-1) once; olive oil of the same volume was given to control group and PSO group intraperitoneally; 12 h, 36 h and 60 h after CCl&#95;4 injection, PSO group and CCl&#95;4+PSO group were administrated with PSO intragastrically at a dose of 200 mg·kg~(-1); 0.5% CMC-Na of the same volume was administrated to control group and PSO group intragastrically. The weight of mice was recorded every day. Serum alanine aminotransferase(ALT) and aspartate aminotransferase(AST) were measured at 36 h, 60 h and 84 h after CCl&#95;4 injection. Mice were sacrificed after collection of the last serum samples. Liver samples were collected, and liver weight was recorded. Histopathological and morphological changes of liver were observed by haematoxylin and eosin staining. The mRNA levels of HGF, TGF-β, TNF-α, p53 and p21 in liver were detected by RT-qPCR. Western blot was used to detect the levels of cell cycle-related proteins. According to the results, significant increase of serum ALT and AST and centrilobular necrosis with massive inflammatory cell infiltration were observed in CCl&#95;4+PSO group. After PSO administration in CCl&#95;4 model, the mRNA levels of HGF(hepatocyte growth factor) and TNF-α were reduced, while the mRNA expressions of TGF-β, p53 and p21 was up-regulated. The expression of PCNA(proliferating cell nuclear antigen) was significantly increased in CCl&#95;4 and CCl&#95;4+PSO group, while the relative protein level in CCl&#95;4+PSO group was slightly lower than that in CCl&#95;4 group. Compared with control and CCl&#95;4 group, the expression of p27(cyclic dependent kinase inhibitor protein p27) was prominently increased in CCl&#95;4+PSO group. These results indicated that hepatotoxicity induced by CCl&#95;4 could be aggravated by intraperitoneal administration with PSO, and the repair process of liver could be delayed. The preliminary mechanism may be related to the inhibition of PCNA and regulation of some cell cycle-associated protein by psoralen, in which the significant up-regulation of p27, p53 and p21 may play important roles.

Selective cutting changes tree species composition and stand structure, modifies tree competition intensity in the stand, with consequences on tree growth and population dynamics. Key tree species play a crucial role in maintaining community structure and ecosystem function. To clarify the competitive characteristics of three key species (Pinus koraiensis, Tilia amurensis, and Fraxinus mandshurica, which accounted for about 70% of growing stock) of typical forest types in broadleaved-Korean pine mixed forest, Hegyi competition index was used in four permanent 1-hm 2 plots, i.e. virgin forest (VF), low-intensity cutting forest (LCF), moderate-intensity cutting forest (MCF) and high-intensity cutting forest (HCF). Compared with VF, the stand density and mean DBH of big trees (DBH≥20 cm) significantly decreased in MCF and HCF, but the stand density of young trees (2 cm≤DBH<10 cm) increased, but no significant changes of stand or DBH in LCF. In all the four forest types, individual competition index (CI) of the three species decreased with increasing DBH. There was a power function relation between CI and DBH. CI curve turned to be gentle at DBH reaching 20 cm, and this rule was not affected by selective cutting. In VF, LCF and HCF, most of competition pressure of young trees of all key species derived from other tree species in secondary canopy or understory, but the competition pressure of small trees (10 cm≤DBH<20 cm) and big trees of P. koraiensis originated mainly from intra-species and other species in secondary canopy or understory. The competition stress of F. mandshurica was mainly affected by P. koraiensis and other species in secondary canopy or understory. T. amurensis was mainly affected by intra-species and P. koraiensis. Betula platyphylla contributed most of the competition stress (over 50%) to all three key species in HCF. Our results suggested that removing the trees which are in secondary canopy or understory but suppress the three key trees species intensively would be beneficial to the regeneration and growth of key species before tree DBH exceeds 20 cm. We proposed to regulate the density of key tree species in overstory to cultivate large diameter timber according to the competition among the key trees species. Once tree DBH exceeds 20 cm, tree growth would not be affected by competition. This study had guiding significance for the cultivation of key tree species and rapid recovery of natural forests after selective cutting.

Non-structural carbohydrates (NSC, including soluble sugars and starch) are key meta-bolites in tree, the storage characteristics of which in tree organs have received extensive attention. It is still unclear how NSC are allocated in the tissues (phloem and xylem) that have different function. In this study, we analyzed the concentration and allocation of NSC in the roots, and in phloem and xylem of the trunk in three dominant species of broadleaved Korean pine forest in the Changbai Mountain, Pinus koraiensis, Fraxinus mandschurica, and Tilia amurensis. The results showed that there was a significant difference in the concentration of NSC between the phloem and xylem. The soluble sugar dominated in the phloem, while starch dominated in the xylem. The concentration of NSC in trunk outside (divided by annual rings, 0-20 years), intermediate (20-40 years) and inner (>40 years) of different tree species was significantly different, but with no difference in the roots. The total soluble sugar concentration in the phloem of P. koraiensis and F. mandschurica was significantly higher than that of T. amurensis, while the difference in xylem was not significant. The results indicated that NSC allocation in the phloem and xylem of the tree had clear tissue differentiation, which might be related to the succession stage of the tree species or the functional evolution of the tissue. These findings would improve our understanding of the carbon storage characteristics and allocation mechanism in temperate trees.

Competition is the main factor affecting the growth, morphology and death of trees in fore-sts. The analysis of individual competition can reflect the characteristics of interaction among individuals and their interaction ranges, which is important for reducing individual competition and promoting tree growth. To understand the effects of competition on tree growth in broad-leaved Korean pine forest, based on Hegyi single-tree competition index and neighborhood analysis method, we explored the neighborhood radius of competition for five key tree species, i.e. Pinus koraiensis, Tilia amurensis, Fraxinus mandshurica, Quercus mongolica and Ulmus japonica (80% of basal area at breast height in total), and analyzed the effects of competition on the growth and death of the key tree species. The results showed that the neighborhood radius of single-tree competition of four tree species, P. koraiensis, T. amurensis, F. mandshurica and Q. mongolica was 11 m, while that of U. pumila was 13 m. The single-tree competition intensity for all five key tree species was negatively correlated with the logarithm of its growth increment, and positively correlated with the size of individual trees. The relative importance of competition intensity on tree growth decreased with tree growth. Neighborhood competition significantly increased tree mortality. Our results revealed the effects of neighborhood competition on the growth and survival of the key tree species at different developmental stages in broad-leaved Korean pine forests in Changbai Mountain. The results are instructive to the adjustment of competitive environment and the improvement of productivity of key tree species in broad-leaved Korean pine forests.

Changbai Mountain is located in the eastern mountain forest region of Northeast China, with broad-leaved Korean pine forest (BKF) as the climax vegetation type. The region is rich in species diversity and serves as an important carrier for precious wood production and forest belts in Northeast China. In the recent 120 years, the vast primary forests in Changbai Mountains have almost disappeared, and have been replaced by secondary forests, over-cut forests, and plantations. Since the founding of the People's Republic of China, the theory and technology of forest management for BKF in Northeast China have gradually improved along with the researches and understanding on the structure and function of BKF, the disputes of Korean pine regeneration characteristics, and the debate about clear cutting and selective cutting. However, the problem of insufficient Korean pine regeneration still exists, and forest management is very extensive. We tried to untangle the management technology trail and research history of BKF in the past 70 years, and to analyze the current forest types and the formation process of the management regulations, with the aim to provide reference for the sustainable management and quality improvement of natural forests in the region.

Changbai Mountain is one of the hotspots for tree ring research in Northeast China, with a large number of related research results having been published. To clarify the advance of tree ring research in Changbai Mountain and understand the responses of tree radial growth to climate factors, we reviewed the related literature and analyzed the differences among them based on tree species identity, elevation, and detrended methods. The radial growth of trees in Changbai Mountain was generally affected by temperature and precipitation, with greater influence of temperature. The relationship between tree radial growth and climate variables varied across both species and altitudes. Most studies reported that the radial growth of conifers were mainly affected by temperature in early growing season (April-May) and growing season precipitation (June-August). The radial growth of broadleaved trees were mainly affected by the temperature in previous and current growing season, the precipitation in dormancy season (November-March), and the precipitation in the current growing season. The previous September precipitation had significant effects on the radial growth of conifers and broadleaved trees. However, many studies had reported different or even opposite results. Most of the differences in the results of the studies appeared at low and medium altitudes, indicating that the altitudinal location of sampling points had impacts on the results. In addition, the detrended method was also the main cause for the variation of results across different studies. Comparatively, the linear or negative exponential detrended method might increase the effective significance of precipitation, especially the effect of precipitation on tree growth during dormancy period, and also strengthen the effective significance of the temperature at the end of the growing season. This study showed the habitat and the detrended method used in chronology were the main reasons for the difference of results among the studies. Therefore, for tree ring research in Changbai Mountain, the number of sampling sites should be increased and the detrended method should be carefully selected.

Exploring the ecological vulnerability of nature reserve and its surrounding area is essential to the maintenance of regional ecological security and sustainability of human development, especially under the stress of global change and human activities. Based on the integration of "sensitivity-resilience-pressure" conceptual model and spatial principal component analysis (SPCA), we analyzed the ecological vulnerability of Changbai Mountain National Nature Reserve and its surrounding 30 km buffer in 2005 and 2015. The main driving factors were further analyzed. The results showed that the ecological vulnerability of Changbai Mountain Nature Reserve was mainly potential, slight, and light levels in 2005 and 2015, indicating the ecological vulnerability inside and outside the reserve was in a good condition. For the whole region, the ecological vulnerability showed a slight downward trend from 2005 to 2015. The degradation area inside and outside the reserve were 254 and 967 km 2 , respectively, with the contribution rate to the increase of overall vulnerability being 30.8% and 69.2%, respectively. The changes in ecological vulnerability inside the reserve were mainly related to the changes in net primary production (NPP), vegetation coverage, and the nearest distance to the road, whereas it was mainly related to the changes in NPP, vegetation coverage and gross domestic product (GDP) density outside the reserve.

To clarify the responses of radial growth of different tree species to climate change and its stability, we explored the relationships between radial growth and climate factors of larch (Larix olgensis) and spruce (Picea jezoensis var. komarovii) distributed at high altitude (1600-1750 m) on the northern slope of Changbai Mountain, using the chronological method. The results showed that the growth of larch was significantly positively correlated with the maximum temperature in June and negatively correlated with the precipitation in June. The radial growth of spruce was significantly positively correlated with the maximum temperature in May. Results from redundancy analysis showed that larch growth was mainly affected by summer temperature, while spruce growth was significantly restricted by spring temperature. During 1959-2014, the relationship between larch growth and summer temperature was relatively stable. For spruce, the correlation between radial growth and spring temperatures had gradually weakened since 1986, mainly due to the growth slowdown because of decreased maximum air temperature. Our results provide theoretical references for predicting the growth response of conifers at Changbai Mountain region in the context of climate change.

Nitrogen deposition and climate warming-drying are the main environmental changes in Northeast China. How they affect forest ecosystems has always been studied in ecological research. In this study, we explored the effects of water stress and nitrogen (N) addition on the short-term (in 55 weeks) growth of seedlings of Pinus koraiensis and Fraxinus mandshurica, two key species in broad-leaved and P. koraiensis mixed forests in temperate zone of Northeast China. Results showed that the responses of seedling growth of P. koraiensis and F. mandshurica to nitrogen addition and water stress were significantly different. P. koraiensis was more sensitive to water stress. In the early stage (in 10 weeks) of water stress, leaf biomass of P. koraiensis significantly decreased while the root biomass increased. Nitrogen addition significantly reduced the root and total biomass of P. koraiensis under water stress. F. mandshurica was more sensitive to N addition. Nitrogen addition rapidly increased the stem, root and total biomass of F. mandshurica. Only sustained water stress could significantly affect the stem, root and total biomass of F. mandshurica. Under continuous water stress and N addition, the biomass contribution of leaves and roots to whole seedling, and the ratio of aboveground to underground biomass of both species tended to be constant, indicating strong self-regulation ability of both species. The results suggested that when drought occurred in the future, P. koraiensis would adopt a "positive" adjustment strategy, while F. mandshurica would adopt a "passive" response. The survival rate and adaptability of P. koraiensis would be higher than F. mandshurica. F. mandshurica would benefit more from N deposition than P. koraiensis. Our results are helpful for predicting the changes of community structure in temperate forest in Northeast China.

The alpine tundra ecosystem, with low soil inorganic nitrogen (N) availability, has a weak buffer against nitrogen and is susceptible to exogenous N enrichment. Here, with a laboratory incubation experiment, we investigated the response of soil carbon and nitrogen mineralization to N deposition with soil samples from the tundra zone on the northern slope of the Changbai Mountain. We set three N levels, control (CK, 0 kg·hm -2 ), low N (N 1 , 25 kg·hm -2 ), and high N (N 2 , 50 kg·hm -2 ), with N being added as NH 4 NO 3 . The results showed that N addition had no significant effect on soil C mineralization rate, but significantly affected the accumulation of soil C minera-lization. The N 2 treatment inhibited soil C mineralization. After the 40 d incubation, soil inorganic N content increased with increasing N addition. After the 80 d incubation, soil inorganic N content in the N 2 and N 1 was similar and significantly higher than that of CK. Those results indicated that N addition promoted soil N mineralization. The soil microbial biomass C and N in the N 1 was higher than that in the N 2 and CK, indicating that low N input had stronger effects on soil microbial activity. Increasing N deposition might accelerate C and N turnover in the tundra soils and enhance the soil inorganic N content. While it could provide more N for plants, it may increase the risk of N loss.

Retinoic acid, an active metabolite of vitamin A, exerts multiple effects on regulating embryonic development and inducing differentiation, proliferation, apoptosis as well as resistance in various cancer cells. Apart from the classic genomic action (binding to the nuclear receptors to regulate the expression of its downstream target genes), retinoic acids also play important roles in anti-cancer effect through non-genomic pathways (via extranuclear and non-transcriptional effects).

Objective: To explore and evaluate the model of antiretroviral treatment that oriented to the medical needs of people living with HIV/AIDS (HIV/AIDS), based on the local prevalence of HIV/AIDS., Methods: A total of 268 HIV/AIDS were selected the CDC of 13 administrative district in Wuhan from 2012 to 2013 and 275 HIV/AIDS were selected in the hospitals of 13 administrative district in Wuhan from 2013 to 2014. The antiretroviral effect of the two groups was compared and the related factors were analyzed., Results: An antiretroviral treatment network that oriented to the medical needs of HIV/AIDS was developed. Data showed that the adherence of patients was better than that when the treatment was carried out at the CDC offices and the status of immuno-recovery on HIV/AIDS was more effective than the hospital-based treatment (P<0.05). Data from multivariable logistic regression analysis showed that different patterns did play different roles on the effects of treatment., Conclusions: The mode of antiretroviral treatment that oriented to the medical needs of HIV/AIDS could effectively improve the adherence and outcomes of treatment. We believe this model could also be adopted elsewhere.

Objective: To evaluate the schistosomiasis control effect of the comprehensive measures that focused on beachland smoothing and tillage cultivation in Tieban Marshland, Wuhan Section of the Yangtze River., Methods: From 2011 to 2015, before and after the comprehensive control, the Oncomelania hupensis snail situations in Tieban Marshland were investigated in spring annually, and the residents aged 6-65 years in Huayuan Community which was next to the marshland were examined to understand their schistosome infection status. In late July, 2014, the sentinel mouse surveillance was carried out. Moreover, the economic effectiveness of comprehensive development was evaluated., Results: The schistosome infection rates of residents in 2011 (before the comprehensive control), 2012 (after the comprehensive control), and 2013 were 0.72% (3/414), 0.37% (2/536) and 0.31% (1/326), respectively, and no schistosomiasis patients were found in 2014 and 2015. The snail area, the occurrence rate of frames with snails, and the average density of living snails in Tieban Marshland in 2005 decreased by 22.18%, 97.83% and 98.25%, respectively compared to those in 2011, and no schistosome infected snails were found. No positive mice were found in the sentinel mouse surveillance. The annual net income of Tieban Marshland increased by 233.33% compared to that before the comprehensive development., Conclusions: The endemic situation of schistosomiasis and snail situation declined significantly after the comprehensive development in Tieban Marshland, and the economic and social benefits are significant.

The five main forest types, i. e. larch forest, birch forest, coniferous mixed forest, broad-leaved mixed forest, and coniferous and broad-leaved mixed forest, with varied age classes (young, mid-aged, pre-mature, and over mature) were selected to investigate the variation of soil organic carbon density in the forest region of Northeast China. Results showed that both soil organic carbon content and density were relatively larger in the top soil layer across the five forest types, decreased gradually with soil depth, and varied insignificantly with either forest type or forest age class. The forest soil carbon density was concentrated in the top 20 cm of soil which accounted for 84.7% - 86.1%, 51.7% - 59.8% and 51.2% - 53.4% of total soil carbon density in the Daxing' an, Xiaoxing' an and Changbai mountains, respectively. The total soil organic carbon density decreased significantly with increasing latitude, which might be attributed mainly to the thickness of soil layers in forest region of Northeast China.

A sampling plot investigation was conducted to study the soil organic carbon (SOC) storage in 0-40 cm layer in 10-, 15-, 26- and 61 years old Larix gmelinii plantations in Great Xing' an Mountains of Northeast China as well as the temporal variation pattern of the SOC source/sink during the plantation management after the clear cutting of primary L. gmelinii forest. With the increasing age of the plantations, the SOC storage increased after an initial decrease, and the inflection point was at a stand age between 15- and 26-years old. Compared with that of primary forest, the SOC storage of the plantations played a role of carbon source at early stage (10-26 years old), but gradually transformed into carbon sink then, with a SOC storage of 158.91 t x hm(-2) in 61-year-old plantation. The SOC storage of the plantations increased with soil depth initially, but was higher in upper soil layer than in deeper soil layer after the stand age being 26, which implied that human disturbance had strong effects on the vertical distribution of SOC. It was considered that the appropriate cutting age for the L. gmelinii plantations in Great Xing' an Mountains could be at least 60 years old.

Through clinical practice and theory of acupuncture, three aspects are expounded in this article, namely whether the sham acupuncture is in reality as well as in name or not, whether the topics assigned as real and sham acupuncture exists or not, and whether the effect of acupuncture equals to placebo or not. It is held that the research method which separates the biological availability and psychological effect does not confirm to the theory of integration of the physical and the psychological in Chinese medicine. It also does not meet the new medical model of biology-psychology-society of the modern society. Therefore, the western research module which separates the physical and psychological should not be repeated. Sham acupuncture as a control method is still immature, which is not appropriate to be taken as a standard model for acupuncture research. If the research method which takes modern medicine as the control method in Chinese Acupuncture and Moxibustion can be promoted, and the most effective and the most advanced methods and results which are general accepted can be taken as the control, the differences and the advantages of acupuncture-moxibustion can be discovered directly with greater value

Objective: To study the influences of Shengbanfang on CYP3A1 activities of SD rat and provide suggestions for drug combinations., Methods: 25 male SD rats were devided into 5 groups randomly,and treated with saline( NS, ig, 10 mg/(kg/d) ,qd,14 d), dexamethasone (DEX, ig, 100 mg/(kg x d), qd, 3 d), high dose of Shengbanfang (HD, ig, 8.645 g/kg, bid, 14 d), middle dose of Shengbanfang (MD, ig, 4.322 g/kg, bid, 14 d) and low dose of Shengbanfang (LD, ig, 2.161 g/kg, bid, 14 d), respectively. The HPLC method was established and validated to determine the productive velocity of 6beta-hydroxytestosterone and measure the activity of CYP3Al., Results: Under the optimized incubation conditions, the productive rates of 6beta-hydroxytestosterone of HD, MD, LD, NS and DEX, groups were (55.82 +/- 5.97), (65.10 +/- 6.83), (60.89 +/- 6.53), (62.17 +/- 6.55), (126.73 +/- 15.40) micromol/(L x mg pro x min). There were significant differences between Shengbanfang groups compared with dexamethasone group, but there was no significant difference between Shengbanfang groups and the control group (NS)., Conclusion: Shengbanfang has no induce effect on the enzymic activity of CYP3Al in SD rats.