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Materials Sciences and Applications 2011年第6期2卷 509-520页

作者： Michel Bocourt Povea Waldo Argüelles Monal Juan Valerio Cauich-Rodríguez alejando may pat Nancy Badas Rivero Carlos Peniche Covas 不详

Interpenetrated polymer networks of chitosan (CHI), polyacrylic acid (PAA) and polyacrylamide (PAM) were prepared by free radical polymerization. These hydrogels were either washed with double distilled water (CHI/PAA/PAM) A or hydrolyzed with 1M sodium hydroxide (NaOH), (CHI/PAA/PAM) S. Both types of hydrogels were characterized by infrared spectroscopy, microstructural techniques and compressive mechanical testing. Finally, hydrogels were loaded with bovine serum albumin (BSA) and release followed at different pHs. Infrared spectra analysis showed correspondence between hydrogels and monomer feed compositions. Hydrolyzed hydrogels, had increased water content and pH swelling dependence. Compression modulus of swelled hydrolyzed hydrogels decreased with increasing equilibrium water content. Higher BSA loadings were achieved on hydrolyzed hydrogels due to their high water content and porosity. Protein release from hydrogels was low (≤ 20% after 10 hours) at pH 1.2, but sustained release was observed at pH 6.8 and 7.4. The integrity of the protein released at 6.8 and 7.4 by hydrolyzed hydrogels was unaffected. The hydrogles showed no cytotoxic effects on human skin dermal fibroblasts as determined by MTT assay except for two compositions of (CHI/PAA/PAM) A samples, which after seven days presented a viability lower than 80% respect to the control.

关键词： Hydrogels Controlled Release Protein Polyacrylamide Interpenetrated Polymer

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微量供油下的线接触副润滑增效分析

中国机械工程 2024年第7期35卷 1205-1211页

作者：李书义郭峰黄柏林金薇梁鹏青岛理工大学机械与汽车工程学院青岛266520 香港城市大学机械工程系中国香港999077

实验发现亲/疏油交替供油的功能润湿表面能提高微量供油下有效润滑的成膜性能。基于此,建立了有限长滚子副润滑模型,分析了交替供油的亲/疏油带宽及工作参数对润滑性能的增强规律。研究发现,微量供油条件下可利用交替供油方式达到线接... 详细信息

实验发现亲/疏油交替供油的功能润湿表面能提高微量供油下有效润滑的成膜性能。基于此,建立了有限长滚子副润滑模型,分析了交替供油的亲/疏油带宽及工作参数对润滑性能的增强规律。研究发现,微量供油条件下可利用交替供油方式达到线接触副润滑增效的目的,但供油交替变换使接触区润滑性能不稳定,且润滑增效作用会受功能表面亲/疏油带宽和卷吸速度的影响。

关键词：线接触副微量润滑功能表面供油

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Extra dimensions and atomic transition frequencies

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Chinese Physics B 2008年第1期17卷 70-75页

作者：李志刚倪维斗 Antonio Pulido patón Center for Gravitation and Cosmology Purple Mountain ObservatoryChinese Academy of Sciences

New unification theories predict large extra dimensions （LEDs）. If that is the case, gravity would be stronger at short ranges than what Newtonian gravity predicts. LEDs could also have effects at atomic level. In this paper we propose a new method to constrain the size of ‘gravity-only’ LEDs by analysing how these LEDs modify the energy of the atomic transitions 1s-2s and 2s-2p （Lamb shift）, in the particular case of the hydrogen and muonium atoms. We estimate these effects by using Bethe＇s non-relativistic treatment of Lamb shift. In the particular case of three LEDs, which may be a candidate to explain the interaction mechanism of dark matter particles, we have found that current knowledge in atomic spectroscopy could constrain their sizes to less than 10 μm. Although our contributions do not reach the sensitivity given by SN1987a, they are still slightly better than recent constraints given by Inverse Square Law tests of the Eoet-Wash group at Washington University, which gave R3 〈 36.6 μm.

关键词： large extra dimensions Lamb shift atomic spectroscopy

Surrogate role of machine learning in motor-drive optimization for more-electric aircraft applications

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Chinese Journal of Aeronautics 2023年第2期36卷 213-228页

作者： Yuan GAO Benjamin CHEONG Serhiy BOZHKO pat WHEELER Chris GERADA Tao YANG Power Electronics Machines and Control GroupUniversity of NottinghamNottingham NG 72RDUK School of Electrical and Electronic Engineering Nanyang Technological UniversitySingapore 639798Singapore

Motor drives form an essential part of the electric compressors,pumps,braking and actuation systems in the More-Electric Aircraft(MEA).In this paper,the application of Machine Learning(ML)in motor-drive design and optimization process is *** general idea of using ML is to train surrogate models for the *** training process is based on sample data collected from detailed simulation or experiment of motor ***,the Surrogate Role(SR)of ML may vary for different *** paper first introduces the principles of ML and then proposes two SRs(direct mapping approach and correction approach)of the ML in a motor-drive optimization *** different cases are given for the method comparison and validation of ML *** first case is using the sample data from experiments to train the ML surrogate *** the second case,the joint-simulation data is utilized for a multi-objective motor-drive optimization *** is found that both surrogate roles of ML can provide a good mapping model for the cases and in the second case,three feasible design schemes of ML are proposed and validated for the two *** the time consumption in optimizaiton,the proposed ML models can give one motor-drive design point up to 0.044 s while it takes more than 1.5 mins for the used simulation-based models.

关键词： Artificial Neural Network(ANN) Design and Optimization Machine Learning(ML) More-Electric Aircraft(MEA) Motor drive Permanent Magnet Synchronous Motor(PMSM) Search Algorithm Surrogate Algorithm

Gene Transfer to Dendritic Cells Induced a Protective Immunity against Melanoma

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Cellular & Molecular Immunology 2005年第4期2卷 281-288页

作者： pat Metharom Kay A.O. Ellem Ming Q. Wei Queensland Institute of Medical Research Herston Department of Medicine University of Queensland Prince Charles Hospital Brisbane Australia

Lentiviral vectors have shown promises for efficient gene transfer to dividing as well as nondividing cells. In this study, we explored lentiviral vector-mediated, the entire mTRP-2 gene transfer and expression in dendritic cells （DCs）. Adoptive transfer of DCs-expressing mTRP-2 （DC-HR＇CmT2） into C57BL/6 mouse was also assessed. Dendritic cells were harvested from bone marrow and functional DCs were proved by allogeneic mixed lymphocyte reaction. Lentiviral vectors were produced by transient transfection of 293T cells. Transduction of DCs was proved by marker gene expression and PCR and RT-PCR amplification. Implantation of the transduced DCs, depletion of immune cells as well as the survival of the mice after tumour challenge were investigated. High efficiency of gene transfer into mature DCs was achieved. The high level expression of the functional antigen （TRP-2） and induction of protective immunity by adoptive transfer of TRP-2 gene modified DCs were demonstrated. In vivo study showed a complete protection of mice from further melanoma cell challenge. In comparison, only 83% of mice survived when mTRP-2 peptide-pulsed DCs were administered, suggesting the generation of specific protection. Together, these results demonstrated the usefulness of this gene transfer to DC approach for immunotherapy of cancer and indicated that using tumour associated antigens （TAAs） for gene transfer may be potentially beneficial for the therapy of melanoma.

关键词： lentiviral vector gene transfer dendritic cell tumour antigen melanoma

A review of phosphorus nutrition in irrigated cotton farming systems of Australia

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Journal of Cotton Research 2022年第1期5卷 72-79页

作者： NACHIMUTHU Gunasekhar SCHWENKE Graeme MERCER Clarence BISCHOF Callum HULME pat BELL Michael New South Wales Department of Primary Industries Australian Cotton Research InstituteNarrabriNSW 2390Australia New South Wales Department of Primary Industries Tamworth Agricultural InstituteCalalaNSW 2340Australia The School of Agriculture and Food Sciences The University of QueenslandGattonQLD 4343Australia Sustainable Soil Management WarrenNSW 2824Australia

Australian cotton production predominantly occurs on *** average lint yield of cotton grown in Australia is 2260–2700 kg·hm^(−2),which is 2.5 to 3 times the world *** high productivity per unit of land area requires efficient use of resources such as water and ***,high yields accelerate the export of nutrients such as phosphorus(P)in seed,depleting the soil reserves of P more than in other countries with lower cotton *** surveys of cotton industry indicate that P application rates should match seed P export(30~40 kg·hm−2),but historical depletion within subsoil is still evident and is *** of soil P is typically more pronounced in the subsoil than in the topsoil(0~20 cm)where P fertiliser is applied,as cotton roots rely on these layers as important sources of plant available water and available *** mismatch between zones of P uptake and resupply may increase stratification of available P in the soil *** studies showed that cotton responded poorly to banded applications of fertiliser P,while dispersal of fertiliser throughout the plant beds was more *** have also observed sporadic cotton responses to applied P fertiliser in soils where available P concentrations were well above the previously determined critical concentrations indicative of fertiliser P responses in *** sustain highyielding cotton production in Australia,a greater understanding of cotton root acquisition of applied P,as well as a re-examination of critical soil P concentrations for each production region are required.

关键词： Vertisol P stratification Soil test critical value

Primary hepatic carcinosarcoma

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Hepatobiliary & Pancreatic Diseases International 2011年第1期10卷 101-103页

作者： Mehmet elikbilek Kemal Deniz Edip Torun Tarιk Artιs Ersin zaslan kkes brahim Karahan Tahir Ercan patιroglu mer zbakιr Department of Gastroenterology Erciyes UniversityMedical School Department of pathology Erciyes UniversityMedical School Department of Surgery Erciyes UniversityMedical School Department of Internal Medicine Erciyes UniversityMedical School

BACKGROUND:Primary hepatic carcinosarcoma is a rare malignant tumor containing an intimate mixture of carci- nomatous and sarcomatous *** on risk factors, epidemiology,and pathogenesis of the tumor as well as the experience in its treatment are limited. METHOD:We present a case of primary carcinosarcoma of the liver in a 69-year-old man who complained of right hypochondrial pain and weight loss for two months. RESULTS:Magnetic resonance imaging revealed a 14×12 cm mass in segments 7-8 and 4 of the liver with vena hepatica *** ultrasonography-guided biopsy showed osteoid tissue without osteoblastic *** structures accompanied the osteoid *** patient underwent surgery after a diagnosis of *** frozen sections revealed a carcinosarcoma associated with an osteosarcoma and cholangiocellular carcinoma components. CONCLUSIONS:Preoperative diagnosis of this rare primary hepatic malignant tumor may be difficult by biopsy owing to intratumoral *** mature areas of the osteosarcomatous component may lead to misdiagnosis of metaplastic bone *** features of this rare entity are discussed.

关键词： carcinosarcoma liver neoplasms osteosarcoma cholangiocarcinoma

Compost Improves Urban Soil and Water Quality

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Journal of Water Resource and Protection 2017年第4期9卷 345-357页

作者： Sally D. Logsdon pat A. Sauer Martin J. Shipitalo USDA-ARS-NLAE 1015 N. University Blvd. Ames IA USA Iowa Stormwater Education Partnership Ames IA USA

Construction in urban zones compacts the soil, which hinders root growth and infiltration and may increase erosion and degrade water quality. The purpose of our study was to determine whether planting prairie grasses and adding compost to urban soils should partially mitigate these concerns. We simulated construction activities by removing the topsoil, and compacting the soil by repeatedly driving over it with a tractor. Additionally, treatments included three compost application methods (compost and aeration, rototill and compost, surface compost). Plots were subjected to simulated rainfall applied using overhead sprinklers at a rate of 65 or 72 mm·h-1. Bulk density was significantly reduced in surface soil where compost had been added. Compost plus prairie grasses resulted in significantly faster infiltration (63 vs. 52 mm·h-1), slower runoff (4 vs. 25 mm·h-2), less soil loss (25 vs. 119 kg·Ha-1·h-1), and reduced loss of ortho P (57 vs. 410 g·Ha-1) compared to plots planted with bluegrass (Poa pratensis L.). A 5 to 7.5 cm thick compost blanket reduced time to runoff (60 min) compared to no compost addition (9 min). Topsoil addition without compost did not develop dark surface soil. Compost additions are recommended to reduce negative effects of urban compaction. Over time, the depth of compost additions decreased, necessitating further additions.

关键词： Degraded Soil Compost Rainfall Simulator Soil Quality

Evidence of Climate Variability in Imo State of Southeastern Nigeria

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Journal of Earth Science and Engineering 2012年第9期2卷 544-553页

作者： Fidelis Chinazor Okorie Ifeyinwa Okeke Austine Nnaji Christian Chibo Edith pat-Mbano Department of Geography and Environmental Management Imo State University Owerri Nigeria Department of Geography University of Lagos Lagos Nigeria Department of Environmental Technology Federal University of Technology Owerri Nigeria Department of Urban and Regional Planning lmo State University Owerri Nigeria

Climate variation generally occurs at local scale, regional scale, national scale and global scale. Having established that the global climate has varied slowly over the past millennia, centuries, and decades and it is expected to continue to vary in future. Like the climate change, variability may be due to, national internal processes within the climate （internal variability）, or variations in natural or anthropogenic external forces （external variability）. Evidence of climate variations is now well documented, and the implications are becoming increasingly clear as data accumulates and data and climate models become increasingly sophisticated. The fluctuations in rainfall and temperature regimes are the atmospheric driving forces that are responsible for the climate variations over the southeastern Nigeria including Imo State as the case in other parts of the world. It is on this premise that this study examined the evidence of climate variability in Imo State of the southeastern Nigeria. The study employed the holistic use of real meteorological data from Nigerian Meteorological Department on two weather parameters （temperature and rainfall）, for 30 years （1980-2009）. Results indicated fluctuations in temperature and rainfall regimes within the period under study, which were the reasons for the variations in climate of the region. Apparently, evidence of climate variability are indicated by increasing surface air temperature, increasing heat waves which enhances disease vectors, communicable diseases and epidemics, sea level rise and associated coastal erosion, flooding, increased evaporation that dry up streams and rivers etc..

关键词： Climate variation meteorological data Imo State Nigeria.

The reproductive performance of female European shags Phalacrocorax aristotelis declines in old age

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The reproductive performance of female European shags Phalac...