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Weight hierarchies of linear codes satisfying the almost chain condition

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Science in China(Series F) 2003年第3期46卷 175-186页

作者：陈文德 torleivklφve Laboratory of Systems and Control Information Security CenterInstitute of Systems ScienceAcademy of Mathematics and System SciencesChinese Academy of SciencesBeijing 100080China Department of Informatics University of Bergen Bergen High Techology Center N-5020 Bergen Norway

The weight hierarchy of a linear [n, k;q] code C over GF(q) is the sequence (d1,d2,..., dk) where dr is the size of the smallest support of an r-dimensional subcode of C. An [n,k;q] code satisfies the chain condition if there exists subcodes D1 D2 … Dk = C of C such that Dr has dimension r and support of size dr for all r. Further, C satisfies the almost chain condition if it does not satisfy the chain condition, but there exist subcodes Dr of dimension r and support of size dr for all r such that D2 D3 Dk = C and D1 D3. A simple necessary condition for a sequence to be the weight hierarchy of a code satisfying the almost chain condition is given. Further, explicit constructions of such codes are given, showing that in almost all cases, the necessary conditions are also sufficient.

关键词： weight hierarchy linear code almost chain condition.

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码的重量谱系的充分条件

科学通报 1997年第2期42卷 223-223页

作者：陈文德 torleivklφve 中国科学院系统科学研究所 DeptofInformatics UnivofBergen

令C是[n,k;q]码,即码长为n,维数为k的q元线性码。对C的任意子码D,定义D的支持是D中码字不全为零的分量的位置集,记为χ(D),D的支持重量为,|χ(D)|。对1≤r≤k。

关键词：码重量谱系充分条件线性码

The Long-term Survival Chances of Young Massive Star Clusters

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Chinese Journal of Astronomy and Astrophysics 2007年第2期7卷 155-186页

作者： Richard de Grijs Geneviève Parmentier Department of Physics & Astronomy The University of Sheffield Hicks Building Hounsfield Road Sheffield S3 7RH U. K.National Astronomical Observatories Chinese Academy of SciencesBeijing 100012 Institute of Astrophysics & Geophysics Université de LiègeAllée du 6 Aot17Sart-Tilman (B5c)B-4000 LiègeBelgium

We review the long-term survival chances of young massive star clusters （YMCs）, hallmarks of intense starburst episodes often associated with Violent galaxy interactions. We address the key question as to whether at least some of these YMCs can be considered protoglobular clusters （GCs）, in which case these would be expected to evolve into counterparts of the ubiquitous old GCs believed to be among the oldest galactic building blocks. In the absence of significant external perturbations, the key factor determining a cluster＇s long-term survival chances is the shape of its stellar initial mass function （IMF）. It is, however, not straightforward to assess the IMF shape in unresolved extragalactic YMCs. We discuss in detail the promise of using high-resolution spectroscopy to make progress towards this goal, as well as the numerous pitfalls associated with this approach. We also discuss the latest progress in worldwide efforts to better understand the evolution of entire cluster systems, the disruption processes they are affected by, and whether we can use recently gained insights to determine the nature of at least some of the YMCs observed in extragalactic starbursts as proto-GCs. We conclude that there is an increasing body of evidence that GC formation appears to be continuing until today; their long-term evolution crucially depends on their environmental conditions, however.

关键词： stellar dynamics - globular clusters general - galaxies interactions - Magellanic Clouds - galaxies starburst - galaxies star clusters

Optimisation of chemical purification conditions for direct application of solid metal salt coagulants:Treatment of peatland-derived diffuse runoff

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Journal of Environmental Sciences 2013年第4期25卷 659-669页

作者： Elisangela Heiderscheidt Jaakko Saukkoriipi Anna-Kaisa Ronkanen Bjφrn Klφve Water Resources and Environmental Engineering Laboratory Department of Process and Environmental Engineering90014 University of OuluFinland Finnish Environment Institute(SYKE) Freshwater CentreMonitoring and AssessmentP.O.Box 413FI-90014University of OuluFinland

The drainage of peatland areas for peat extraction, agriculture or bioenergy requires affordable, simple and reliable treatment methods that can purify waters rich in particulates and dissolved organic carbon. This work focused on the optimisation of chemical purification process for the direct dosage of solid metal salt coagulants. It investigated process requirements of solid coagulants and the influence of water quality, temperature and process parameters on their performance. This is the first attempt to provide information on specific process requirements of solid coagulants. Three solid inorganic coagulants were evaluated： aluminium sulphate, ferric sulphate and ferric aluminium sulphate. Pre-dissolved aiuminium and ferric sulphate were also tested with the objective of identifying the effects of in-line coagulant dissolution on purification performance. It was determined that the pre-dissolution of the coagulants had a significant effect on coagulant performance and process requirements. Highest purification levels achieved by solid coagulants, even at 30% higher dosages, were generally lower （5%-30%） than those achieved by pre-dissolved coagulants. Furthermore, the mixing requirements of coagulants pre-dissolved prior to addition differed substantially from those of solid coagulants. The pH of the water samples being purified had a major influence on coagulant dosage and purification efficiency. Ferric sulphate （70 mg/L） was found to be the best performing solid coagulant achieving the following load removals： suspended solids （59%-88%）, total organic carbon （56%-62%）, total phosphorus （87%-90%）, phosphate phosphorus （85%-92%） and total nitrogen （33%-44%）. The results show that the use of solid coagulants is a viable option for the treatment of peatland-derived runoff water if solid coagulant-specific process requirements, such as mixing and settling time, are considered.

关键词： inorganic solid coagulant peatland runoff mixing chemical purification nutrients humic substances

Machine learning model for snow depth estimation using a multisensory ubiquitous platform

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Journal of Mountain Science 2022年第9期19卷 2506-2527页

作者： Sofeem NASIM Mourad OUSSALAH Björn KLÖve Ali Torabi HAGHIGHI Department of Computer Science and Engineering University of OuluOulu 90570Finland Water Energy and Environmental EngineeringUniversity of OuluOulu 90570Finland

Snow depth estimation is an important parameter that guides several hydrological applications and climate change *** advances in remote sensing technology and enhanced satellite observations,the estimation of snow depth at local scale still requires improved accuracy and *** advances in ubiquitous and wearable technology promote new prospects in tackling this *** this paper,a wearable IoT platform that exploits pressure and acoustic sensor readings to estimate and classify snow depth classes using some machine-learning models have been put ***,the results of Random Forest classifier showed an accuracy of 94%,indicating a promising alternative in snow depth measurement compared to in situ,LiDAR,or expensive large-scale wireless sensor network,which may foster the development of further affordable ecological monitoring systems based on cheap ubiquitous sensors.

关键词： Snow depth Wearable technology Machine learning Random forest classifier

Organic matter produced by algae and cyanobacteria: Quantitative and qualitative characterization

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Journal of Environmental Sciences 2013年第6期25卷 1089-1097页

作者： Maud Leloup Rudy Nicolau Virginie Pallier Claude Yprmian Geneviève Feuillade-Cathalifaud University of Limoges EA 4330Groupement de Recherche EauSolEnvironnement(GRESE)ENSILParc d'ESTER Technople16 rue AtlantisF-87068 Limoges CedexFrance UMR 7245 MCAM MNHN-CNRS Equipe CyanobactériesCyanotoxines et EnvironnementMuséum National d'Histoire NaturelleCase 3912 rue BuffonF-75231 Paris Cedex 05France

This work aims at characterizing organic matter produced by an alga Euglena gracil~ and a cyanobacteria Microcystis aeruginosa and assessing the evolution of its characteristics during growth. A culture medium was optimized. The species growth phases were monitored using both visible spectrophotometry and flow cytometry cell counting. Organic matter fractionation according to hydrophobicity and specific UV absorbance （SUVA） index were used to specifically characterize the produced algal organic matter （AOM）. The AOM characteristics were both growth phase and species dependent. However, a similar evolution was observed. The hydrophilic fraction （HPI） was the major fraction whatever the growth phases and was almost the only one produced during lag and exponential phases. It represented around 75% of AOM during exponential phase and then decreased when the stationary phase appeared. It represented 46% and 60% of the AOM during late decline phase for the cyanobacteria and the alga respectively. The hydrophobic （HPO） and transphilic （TPH） fractions started to appear from the beginning of the stationary phase with more hydrophobic compounds coming from intracellular organic material of dying cells. HPO and TPH percentages still increased during the decline phase probably because of two additional processes： photo-dissolution and leaching of particulate organic matter from cells fragments. A comparison of AOM during late decline phase and natural organic matter （NOM） from Glane River （France） underlined that AOM was more fiydrophilic and presented a lower SUVA for each fractions than NOM. However, the difference between NOM and AOM hydrophobicity narrowed during decline phase.

关键词： algae cyanobacteria organic matter XAD fractionation SUVA flow cytometry

Differences in oxidative stress dependence between gastric adenocarcinoma subtypes

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World Journal of Gastroenterology 2006年第7期12卷 1005-1012页

作者： Brigitte Bancel JacauesEstève Jean-Christophe Souquet Shinya Toyokuni Hiroshi Ohshima Brigitte Pignatelli Hospital de la Croix-Rousse Department of PathologyLyonFrance Centre Hospital de la Croix-Rousse Department of GastroenterologyLyonFrance Department of Pathology and Biology of Diseases Graduate School of MedicineKyoto UniversityKyotoJapan Brigitte Pignatelli International Agency for Research on Cancer.Endogenous Risk Factors GroupLyon.France Clinical Epidemiology Unit Department of Medical InformationHospices Civils de LyonFrance

AIM： To investigate the extent of oxidative stress in preneoplastic and neoplastic gastric mucosa in relation to their pathological criteria and histological subtypes. METHODS： A total of 104 gastric adenocarcinomas from 98 patients （88 infiltrative and 16 intraepithelial tumors） were assessed immunohistochemically for expression of iNOS and occurrence of nitrotyrosine （NTYR）-containing proteins and 8-hydroxy-2＇-deoxyguanosine （8-OH- dG）-containing DNA, as markers of NO production and damages to protein and DNA. RESULTS： Tumor cells staining for iNOS, NTYR and 8-OH-dG were detected in 41%, 62% and 50% of infiltrative carcinoma, respectively. The three markers were shown for the first time in intraepithelial carcinoma. The expression of iNOS was significantly more frequent in tubular carcinoma （TC） compared to diffuse carcinoma （DC）（54% vs 18%; P=0.008） or in polymorphous carcinoma （PolyC）（54% vs 21% ; P=0.04）. NTYR staining was obviously more often found in TC than that in PolyC （72% vs 30% ; P=0.03）. There was a tendency towards a higher rate of iNOS staining when distant metastasis （pM） was present. In infiltrative TC, the presence of oxidative stress markers was not significantly correlated with histological grade, density of inflammation, the depth of infiltration （pT）, lymph nodes dissemination （pN） and pathological stages （pTNM）.CONCLUSION： The iNOS-oxidative pathway may play an important role in TC, but moderately in PolyC and DC. DNA oxidation and protein nitration occur in the three subtypes. Based on the significant differences of NTYR levels, TC and PolyC appear as two distinct subtypes.

关键词： Gastric neoplasms Nitric oxide synthase Hpylori Nitrotyrosine 8-hydroxydeoxyguanosine Oxidative stress

Short-term effects of obestatin on hexose uptake and triacylglycerol breakdown in human subcutaneous adipocytes

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World Journal of Diabetes 2018年第1期9卷 25-32页

作者： Christian Carpéné Francisco Les David Estève Jean Galitzky Institut des Maladies Métaboliques et Cardiovasculaires Institut National de la Santé et de la Recherche Médicale Université Paul Sabatier Department of Pharmacy Faculty of Health Sciences Universidad San Jorge

AIM To study complete dose-dependent effects of obestatin on lipolytic and glucose transport activities in human adipocyte preparations highly responsive to *** Adipocytes were prepared by liberase digestion from subcutaneous abdominal adipose tissue obtained from overweight subjects undergoing plastic surgery. The index of lipolytic activity was the glycerol released in the incubation medium, while glucose transport was assessed by [~3H]-2-deoxyglucose uptake *** When tested from 0.1 nmol/L to 1 μmol/L, obestatin did not stimulate glycerol release; it did not inhibit the lipolytic effect of isoprenaline and did not alter the insulin antilipolytic effect. Obestatin hardly activated glucose transport at 1 μmol/L only. Moreover, the obestatin stimulation effect was clearly lower than the threefold increase induced by insulin 100 nmol/*** Low doses of obestatin cannot directly influence lipolysis and glucose uptake in human fat cells.

关键词： Insulin Lipolysis Adipokines Glucose uptake Obestatin Human adipocytes

Vanadium-dependent activation of glucose transport in adipocytes by catecholamines is not mediated via adrenoceptor stimulation or monoamine oxidase activity

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World Journal of Diabetes 2020年第12期11卷 622-643页

作者： Jessica Fontaine Geneviève Tavernier Nathalie Morin Christian Carpéné Institut des Maladies Métaboliques et Cardiovasculaires Institut National de la Santéet de la Recherche MédicaleINSERM UMR1048UniversitéPaul Sabatier Toulouse IIIToulouse 31432France INSERM UMR 1139 Facultéde Pharmacie Universitéde ParisParis 75006France

BACKGROUND Benzylamine and methylamine activate glucose uptake in *** tyramine,this effect has even been extended to *** To investigate the effects of catecholamines and other amines on glucose *** A screening compared 25 biogenic amines on 2-deoxyglucose(2-DG)uptake activation in rat *** approaches and transgenic mouse models were then used to decipher the mode of action of several *** In rat adipocytes,insulin stimulation of 2-DG uptake was reproduced with catecholamines.100μmol/L or 1 mmol/L adrenaline,noradrenaline,dopamine and deoxyepinephrine,maximally activated hexose transport only when sodium orthovanadate was added at 100μmol/*** activation was similar to that already reported for benzylamine,methylamine and tyramine,well-recognized substrates of semicarbazide-sensitive amine oxidase(SSAO)and monoamine oxidase(MAO).Several,but not all,tested agonists ofβ-adrenoreceptors(β-ARs)also activated glucose transport whileα-AR agonists were *** of blockade byα-andβ-AR antagonists indicated that catecholamine-induced 2-DG uptake was not mediated by AR *** from mice lackingβ1-,β2-andβ3-ARs(triple KO)also responded to millimolar doses of adrenaline or noradrenaline by activating hexose transport in the presence of 100μmol/L *** MAO blocker pargyline,and SSAO inhibitors did not block the effects of adrenaline or noradrenaline plus vanadate,which were blunted by *** Catecholamines exert unexpected insulin-like actions in adipocytes when combined with *** limiting insulin resistance by activating glucose consumption at least in fat stores,we propose that catecholamine derivatives combined with vanadium can generate novel complexes that may have low toxicity and promising anti-diabetic properties.

关键词： Adipocyte Amine oxidases Insulin Diabetes Vanadium Obesity