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Small mammal community response to early meadow–forest succession

Forest Ecosystems 2017年第3期4卷 211-220页

作者： Linas Bal?iauskas Au?ra ?epukien? Laima Bal?iauskien? Nature research centre

Background： With farmland afforestation becoming common policy in many European Union countries, we studied how early forest succession（from meadow to young stand） influences small mammal species composition, diversity,abundance and biomass. Despite numerous investigations into forest succession, almost no attention has been given to the small mammal community change in the early-successional forest ecosystems, starting with the pre-forest habitat and ending with stand formation and the establishment of tree dominance. We compared small mammal communities in meadows at the initial stage of regrowth（with saplings less than 10 cm in height）, in young forest（5–10 years old） and more advanced forest（15–20 years） in both cases of human-induced forest succession, where the trees had been planted, and natural forest succession, where natural regrowth of meadows had ***： The greatest diversity of small mammal species was recorded in the meadow（H = 2.95）, with a lower diversity found in the young forest（H = 2.61） and even lower in the advanced forest（H = 2.04）, the last habitat being the most monodominantic. The order of species dominance from Microtus sp.（M. arvalis, M. agrestis）, Myodes glareolus, Apodemus flavicollis, Sorex araneus, A. agrarius in the meadow changed to M. glareolus, S. araneus, M. arvalis,M. agrestis in the young forest and to M. glareolus, A. flavicollis, S. araneus in the advanced forest. The lowest relative abundance of small mammals was recorded in the meadow（18.19 ± 2.27 ind. Per 100 trap-days）, with Microtus voles being the most abundant. Relative abundance was higher in the young forest（22.72 ± 2.25 ind. Per 100 trap-days）,with Myodes glareolus being the most abundant（7.59 ± 0.96 ind. Per 100 trap-days） and at its highest in the advanced forest（23.91 ± 2.77 ind. Per 100 trap-days）, again with M. glareolus being the most abundant（15.54 ± 2.35 ind. Per100 trap-days）.Conclusions： Thus, our analysis suggests that that during early meadow-f

关键词： Afforestation Voles Mice Diversity Abundance Biomass

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Tribological Performance of Coated Surfaces

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材料热处理学报 2004年第5期25卷 20-27页

作者： Kenneth Holmberg Anssi Laukkanen VTT Technical research centre of Finland Espoo FinlandVTT Technical Research Centre of Finland Espoo Finland

The fundamentals of coating tribology is presented in a generalised holistic approach to friction and wear mechanisms of coated surfaces in dry sliding contacts. It is based on a classification of the tribological contact process into macromechanical, micromechanical, tribochemical contact mechanisms and material transfer. The tribological contact process is dominated by the macromechanical mechanisms, which have been systematically analysed by using four main parameters: the coating-to-substrate hardness relationship, the film thickness, the surface roughness and the debris in the contact. In this paper special attention is given to the microlevel mechanisms, and in particular new techniques for modelling the elastic, plastic and brittle behaviour of the surface by finite element (FEM) computer simulations. The contact condition with a sphere sliding over a plate coated with a very thin hard coating is analysed. A three dimensional FEM model has been developed for calculating the first principal stress distribution in the scratch tester contact of a diamond spherical tip moving with increased load on a 2 thick titanium nitride (TiN) coated steel surface. The model is comprehensive in that sense that it considers elastic, plastic and fracture behaviour of the contact surfaces. By identifying from a scratch experiment the location of the first crack and using this as input data can the fracture toughness of the coating be determined.

关键词：硬敷层 FEM 应力模拟断口摩擦性能贴合表面

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Inconel 617 and Stellite 6 alloys for tooling in thixoforming of steels

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Transactions of Nonferrous Metals Society of China 2010年第9期20卷 1656-1662页

作者： Y.BI ROL Materials Institute Marmara Research Centre

Thermal fatigue and high temperature wear are the two principle failure mechanisms for thixoforming dies. Samples of Inconel 617 and Stellite 6 alloys were submitted to thermal cycling under conditions which approximate thixoforming of steels and to sliding wear tests at 750 ℃. The experimental results thus obtained were compared with those of the X32CrMoV33 hot work tool steel. The Inconel 617 and Stellite 6 samples are much more resistant to oxidation and to softening than the hot work tool steel, providing a superior resistance to thermal fatigue cracking. The wear resistance of the Inconel 617 and Stellite 6 alloys at 750 ℃ is also markedly superior. The adhesive oxides growing slowly on Inconel 617 and Stellite 6 alloys sustain the wear action without spalling and are claimed to be responsible for the superior wear resistance of these alloys at 750 ℃.

关键词： steel thixoforming tooling thermal fatigue wear

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Clinical benefits of biochemical markers of bone turnover in Egyptian children with chronic liver diseases

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World Journal of Gastroenterology 2007年第5期13卷 785-790页

作者： Karam A Mahdy Hanaa H Ahmed Fathia Mannaa Azza Abdel-Shaheed Medical Biochemistry Department National Research Centre Egypt Hormones Department National Research Centre Egypt Medical Physiology Department National Research Centre Egypt Child Health Department National Research Centre Egypt

AIM： To investigate the association between serum insulin-like growth factor 1 （IGF-1）, osteocalcin, and parathyroid hormone （PTH） levels with the etiology and clinical condition of patients with chronic liver disease. METHODS： Eighty children with hepatocellular damage were divided into 3 groups according to the etiology of disease infection： bilharziasis （9 patients）, hepatitis B virus （HBV, 12 patients） and hepatitis C virus （HCV, 29 patients）. The Child score index was found as A in 24 patients, B in 22 patients, C in 4 patients. Thirty healthy children served as control ***, HBcAbIgM, HBcAbIgG, and anti-HCV were detected using ELISA technique. HCV-RNA was measured by reverse transcription polymerase chain reaction （RT-PCR）. Antibllharzial antibodies were detected by indirect haemagglutination test. Liver function tests were performed using autoanalyser. Serum IGF-1, osteocalcin and PTH levels were measured by ELISA technique. Abdominal ultrasonography was also conducted. RESULTS： Serum IGF-1 level was significantly lower in all patient groups with liver diseases, while serum osteocalcin and PTH levels were significantly elevated in patients with HBV and HCV infections compared with the control group. Serum osteocalcin and PTH concentrations were measured with the severity of liver disease from Child A to C. Child A patients unexpectedly showed significantly reduced IGF-1 levels in comparison to patients staged as Child B or C. Serum osteocalcin level was negatively correlated with albumin （14.7 ± 0.54 vs 3.6 ± 0.10, P 〈 0.05）, while that for PTH was positively correlated with total protein （70.1 ± 2.17 vs 6.7 ± 0.10, P 〈 0.05） in patients with HCV infection.

关键词： Liver disease Bone turnover Insulin-like growth factor-1 Osteocalcin Parathyroid hormone

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Synthesis, characterization, cytotoxicity, DNA cleavage and antimicrobial activity of homodinuclear lanthanide complexes of phenylthioacetic acid

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Journal of Rare Earths 2013年第10期31卷 1009-1016页

作者： T. F. Abbs Fen Reji A. Jeena Pearl Bojaxa A. Rosy Department of Chemistry & research centre Nesamony Memorial Christian College Department of Chemistry& research centre Scott Christian College Department of Botany & research centre Holy Cross College (Autonomous)

Lanthanide complexes of Eu（III）, Gd（III）, Nd（III）, Sm（III）, and Tb（III） with phenylthioacetic acid were synthesized and characterized by elemental analysis, mass, infrared radiation （IR）, electronic spectra, molar conductance, thermogravimetric analysis （TGA）, and powder X-ray diffraction （XRD）. The results showed that the lanthanide complexes were homodinuclear in nature. The two lanthanide ions were bridged by eight oxygen atoms from four carboxylate groups. Thermal decomposition profiles were consis- tent with the proposed formulations. Powder XRD studies showed that all the complexes were amorphous in nature. Antimicrobial studies indicated that these complexes exhibited more activity than the ligand itself. The DNA cleavage activity of the ligand and its complexes were assayed on CT DNA using gel electrophoresis in the presence of H202. The result showed that the Eu（Ⅲ） and Nd（Ⅲ） complexes completely cleaved the DNA. The anticancer activities of the complexes were also studied towards human cervical cancer cell line （HeLa） and colon cancer cells （HCT116） and it was found that the Eu（Ⅲ） and Nd（Ⅲ） complexes were more active than the corresponding Gd（Ⅲ）, Sm（Ⅲ）, Tb（Ⅲ） complexes and the free ligand on both the cancer cells.

关键词： lanthanide complexes phenylthioacetic acid antimicrobial DNA cleavage anticancer rare earths

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Injection-switchable erbium-doped fiber laser with two output ports

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Chinese Optics Letters 2007年第2期5卷 96-98页

作者：陈达如秦山 centre for Optical and Electromagnetic research Joint Research Centre of Optical CommunicationsZhejiang UniversityHangzhou 310058

An injection-switchable erbium-doped fiber laser （EDFL） with two output ports based on a ring structure is proposed. Wavelength switching together with the switching of the dominating output port of the fiber laser is achieved by controlling the power of a tunable injection laser. The characteristics of the wavelength switching for different levels of the pump laser power and different wavelengths of the injection laser are studied experimentally.

关键词： Injection lasers Switching Wavelength

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Sex-dependent alterations in extracellular vesicles linking chronic spinal cord injury to brain neuroinflammation and neurodegeneration

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Neural Regeneration research 2025年第2期20卷 483-484页

作者： Yun Li Junfang Wu Department of Anesthesiology&Shock Trauma and Anesthesiology Research(STAR)CenterUniversity of Maryland School of MedicineBaltimoreMDUSA

Traumatic spinal cord injury(SCI)is a devastating exogenous injury with long-lasting consequences and a leading cause of death and disability *** in assistive technology,rehabilitative interventions,and the ability to identify and intervene in secondary conditions have significantly increased the long-term survival rate of SCI patients,with some people even living well into their seventh or eighth *** survival changes have led neurotrauma researchers to examine how SCI interacts with brain *** health and epidemiological data showed that patients with long-term SCI can have a lower life expectancy and quality of life,along with a higher risk of comorbidities and complications.

关键词： alterations inflammation injury

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Advancements in Liver Tumor Detection:A Comprehensive Review of Various Deep Learning Models

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Computer Modeling in Engineering & Sciences 2025年第1期142卷 91-122页

作者： Shanmugasundaram Hariharan D.Anandan Murugaperumal Krishnamoorthy Vinay Kukreja Nitin Goyal Shih-Yu Chen Deptartment of Artificial Intelligence and Data Science Vardhaman College of EngineeringHyderabad501218India Deptartment of CSE V.S.B College of EngineeringKarur639111India Deptartment of Electrical and Electronics Engineering Vardhaman College of EngineeringHyderabad501218India centre for research Impact&Outcome Chitkara UniversityRajpura140401PunjabIndia Department of Computer Science and Engineering School of Engineering and TechnologyCentral University of HaryanaMahendergarh123031HaryanaIndia Department of Computer Science and Information Engineering National Yunlin University of Science and TechnologyYunlin64002Taiwan Intelligence Recognition Industry Service research Center National Yunlin University of Science and TechnologyYunlin64002Taiwan

Liver cancer remains a leading cause of mortality worldwide,and precise diagnostic tools are essential for effective treatment *** Tumors(LTs)vary significantly in size,shape,and location,and can present with tissues of similar intensities,making automatically segmenting and classifying LTs from abdominal tomography images crucial and *** review examines recent advancements in Liver Segmentation(LS)and Tumor Segmentation(TS)algorithms,highlighting their strengths and limitations regarding precision,automation,and *** metrics are utilized to assess key detection algorithms and analytical methods,emphasizing their effectiveness and relevance in clinical *** review also addresses ongoing challenges in liver tumor segmentation and identification,such as managing high variability in patient data and ensuring robustness across different imaging *** suggests directions for future research,with insights into technological advancements that can enhance surgical planning and diagnostic accuracy by comparing popular *** paper contributes to a comprehensive understanding of current liver tumor detection techniques,provides a roadmap for future innovations,and improves diagnostic and therapeutic outcomes for liver cancer by integrating recent progress with remaining challenges.

关键词： Liver tumor detection liver tumor segmentation image processing liver tumor diagnosis feature extraction tumor classification deep learning machine learning

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Forecasting the effects of EU policy measures on the nitrate pollution of groundwater and surface waters

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Journal of Environmental Sciences 2010年第6期22卷 872-877页

作者： Ralf Kunkel Peter Kreins Bjrn Tetzlaff Frank Wendland research centre Jülich Institute of Chemistry and Dynamics of the Geosphere Institute of Rural Studies Federal Agricultural Research Centre

We used the interdisciplinary model network REGFLUD to predict the actual mean nitrate concentration in percolation water at the scale of the Weser river basin （Germany） using an area differentiated （100 m × 100 m） approach. REGFLUD combines the agro-economic model RAUMIS for estimating nitrogen surpluses and the hydrological models GROWA/DENUZ for assessing the nitrate leaching from the soil. For areas showing predicted nitrate concentrations in percolation water above the European Union （EU） groundwater quality standard of 50 mg NO3-N/L, effective agri-environmental reduction measures need to be derived and implemented to improve groundwater and surface water quality by 2015. The effects of already implemented agricultural policy are quantified by a baseline scenario projecting the N-surpluses from agricultural sector to 2015. The REGFLUD model is used to estimate the effects of this scenario concerning groundwater and surface water pollution by nitrate. From the results of the model analysis the needs for additional measures can be derived in terms of required additional N-surplus reduction and in terms of regional prioritization of measures. research work will therefore directly support the implementation of the Water Framework Directive of the European Union in the Weser basin.

关键词： catchment management diffuse source pollution mitigation methods river basin management Water Framework Directive

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Neuroprotection by misoprostol against rotenone-induced neurotoxicity in rat brain

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Asian Pacific Journal of Tropical Medicine 2018年第1期11卷 40-47页

作者： Omar M.E.Abdel-Salam Amany A Sleem Eman R Youness Nadia A Mohammed Enayat A Omara Department of Toxicology and Narcotics National Research Centre Department of Pharmacology National Research Centre Department of Medical Biochemistry National Research Centre Department of Pathology National Research Centre

Objective: To investigate the effect of the prostaglandin E1 analogue misoprostol on oxidative stress and neurodegeration caused by subcutaneous rotenone administration in rats. Methods:Rotenone was administered in a dose of 1.5 mg/kg every other day for 2 weeks. Starting from the 1 st day of rotenone injection, rats were subcutaneously treated with misoprostol at doses of10, 100 or 1 000 μg/kg. Rats were evaluated for brain lipid peroxidation(malondialdehyde:MDA), reduced glutathione(GSH), nitric oxide(NO) levels, and paraoxonase-1(PON-1) *** concentrations of the anti-apoptotic protein B cell/lymphoma-2(Bcl-2) were determined in the striatum. Histopathologic examination and the expression of inducible nitric oxide synthase(iNOS) in the cerebral cortex and striatum were also performed. Results: Compared with the vehicle-treated group, rotenone caused a significant increase in brain lipid proxidation(MDA)by 61%(P<0.05) accompanied by an increase in NO by 73.1%(P<0.05) and a decrease in GSH concentration by 29.4%(P<0.05). In addition, brain PON-1 activity significantly decreased by63.0%(P<0.05) and striatal Bcl-2 significantly decreased by 27.9%(P<0.05) with respect to the corresponding control value. Brain sections from rotenone treated rats showed extensive dark pyknotic and apoptotic nuclei in neurons, shrunken cytoplasm and perineuronal *** also caused pronounced expression of iNOS in the cerebral cortex and *** with misoprostol at doses of 100 and 1 000 μg/kg resulted in decreased brain MDA(by 16.5%-23.0%)(P<0.05) and NO levels(by 37.1%-40.7%)(P<0.05) and increased GSH concentrations(by 18.8%-30.1%)(P<0.05). PON-1 activity was significantly increased by80.0%-114.8%(P<0.05) by misoprostol at 100 and 1 000 μg/kg, respectively. In addition,misoprostol treatment restored striatal Bcl-2 concentrations to its normal value. Misoprostol treatment resulted in markedly reduced brain injury and decreased iNOS expression in the cereb

关键词： Misoprostol Rotenone Brain oxidative stress B cell/lymphoma-2 Paraoxonase

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