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婴儿期日间护理与儿童期急性淋巴细胞性白血病发病风险的研究:在英国开展的病例对照研究

世界核心医学期刊文摘（儿科学分册） 2005年第11期1卷 6-6页

作者： Gilham C. Peto J. Simpson J. t.o.b. eden 张振 Academic Unit of Paediatric oncology Christie Hospital and Central Manchester Manchester Children's University Hospitals NHS Trusts Manchester M20 4BX United Kingdom

objective: to test the hypothesis that reduced exposure to common infections in the first year of life increases the risk of developing acute lymphoblastic leukaemia. Design and setting: the United Kingdom childhood cancer study (UKCCS) is a large population based case-control study of childhood cancer across 10 regions of the UK Participants 6305 children (aged 2-14 years) without cancer; 3140 children with cancer (diagnosed 1991-6), of whom 1286 had acute lymphoblastic leukaemia (ALL). Main outcome measure: Day care and social activity during the first year of life were used as proxies for potential exposure to infection in infancy. Results: Increasing levels of social activity were associated with consistent reductions in risk of ALL; a dose-response trend was seen. When children whose mothers reported no regular activity outside the family were used as the reference group, odds ratios for increasing levels of activity were 0.73 (95%confidence interval 0.62 to 0.87) for any social activity, 0.62 (0.51 to 0.75) for regular day care outside the home, and 0.48 (0.37 to 0.62) for formal day care (attendance at facility with at least four children at least twice a week) (P value for trend though not as striking, results for non-ALL malignancies showed a similar pattern (P value for trend th non-ALL malignancies were taken as the reference group, a significant protective effect for ALL was seen only for formal day care (odds ratio = 0.69, 0.51 to 0.93; P = 0.02). Similar results were obtained for b cell precursor common ALL and other subgroups, as well as for cases diagnosed above and below age 5 years. Conclusion: these results support the hypothesis that reduced exposure to infection in the first few months of life increases the risk of developing acute lymphoblastic leukaemia.

关键词：发病风险婴儿期病例对照研究儿童癌症儿童期癌症出生后潜在感染验证研究感染性疾病感染源

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burrow morphology of Uca uruguayensis and Uca leptodactylus(Decapoda:ocypodidae)from a subtropical mangrove forest in the western Atlantic

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Integrative Zoology 2013年第3期8卷 307-314页

作者： Glauco b.o.MACHADo João b.L.GUSMÃo-JUNIoR tânia M.CoStA Campus Experimental do Litoral Paulista UNESPSão VicenteSão PauloBrazil

the continuous excavation of burrows by fiddler crabs generates bioturbation in the sediment,which can be estimated from burrow *** aim of the present study was to describe the burrow morphology of Uca uruguayensis and *** and its relationship with demography of resident individuals and to estimate the level of bioturbation in the sediment generated by each *** all individuals from each of the 2 species,sex was determined and the carapace width(CW;mm)*** were characterized according to burrow diameter(bD;mm),maximum burrow depth(MbD;mm)and burrow volume(bV;cm^(3)).the density of each species in the study area was also *** both species,the males were larger and occupied burrows with higher bV compared to *** between sexes in relation to the burrow characteristics might reflect sexual dimorphism within the group and are probably related to the fact that males use the burrows for *** and bV showed significant positive relationships with the size of resident *** amount of sediment removed per burrow was estimated from mean bV:10.78 cm^(3)of sediment/burrow for *** and 12.38 cm^(3)of sediment/burrow for *** the density and depth differences between the 2 species,the similarity in burrow volume suggests that *** and *** present the same importance in terms of the bioturbation *** morphology is highly associated with characteristics of the occupant,although extrinsic factors should also be considered,and its description can provide estimates on the bioturbation generated by Uca species in mangrove forests.

关键词： bioturbation burrow structure crab burrowing fiddler crab

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titanate Nanorods Modified with Nanocrystalline ZnS Particles and their Photocatalytic Activity on Pollutant Removal

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Journal of Materials Science & technology 2016年第11期32卷 1122-1128页

作者： G.Naudin t.Entradas b.barrocas o.C.Monteiro Faculte de Chimie Universite Pierre et Marie Curie (UPMC) Batiment F 3e etage 4 placeJussieu 75005 Paris France Centro de Quimica e bioquimica Faculdade de Ciencias Universidade de Lisboa 1749-016 Lisboa Portugal

Aiming to produce materials with enhanced photocatalytic properties, the synthesis of new crystalline nanocomposites by combining titanate nanorods（tNR） with ZnS nanocrystallites is described in this *** tNR modification was accomplished by an in situ nucleation and growth process of ZnS *** diethyldithiocarbamate was used as the metal chalcogenide precursor. the prepared materials were structural, morphological and optical characterized by X-ray diffraction, transmission electron microscopy and high resolution transmission electron microscopy, energy dispersive spectroscopy and powder diffuse reflectance spectra. Crystalline Zn S nanoparticles were obtained as a homogeneous and continuous layer, covering completely the tNR surface. the application of these new nanocomposite materials on photocatalytic degradation of pollutants was investigated. First, the evaluation of hydroxyl radical formation, using the terephthalic acid as probe, was studied. Afterwards, the adsorption and photodegradation of safranine-t, used here as a model pollutant molecule, was investigated. the obtained data indicate that the prepared nanocomposites have potential to be used as photocatalysts for organic pollutant *** best removal results（97% removal） were obtained using the 0.01 Zn S/HtNR sample as catalyst（0.2 g/L; 10 ppm safranin-t solution） with a combination of a low dye adsorption（20%） and a high dye photocatalytic degradation（77%）.

关键词： Nanocomposite materials Surface modification Photocatalysis Adsorption ability optical properties

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Gaseous Nitrogen Losses from Coastal Acid Sulfate Soils:A Short-term Study

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Pedosphere 2011年第2期21卷 197-206页

作者： b.C.t.MACDoNALD o.t.DENMEAD I.WHItE G.bYRANt CSIRo Land and Water CanberraACT 2601 (Australia) the Fenner School of Environment and Society Australian National UniversityCanberraACT 0200 (Australia) University of Wollongong WollongongNSW 2500 (Australia)

Nox and N2o emissions from coastal acid sulfate soils （CASS） cultivated for sugarcane production were investigated on the coastal lowlands of northern New South Wales, Australia. two series of short-term measurements were made using chambers and micrometeorological techniques. Series i occurred during the wet season, the water-filled pore space （WFPS） was between 60%-80% and the site flooded during the measurements. Measurements were made directly after the harvest of soybean crop, which fixed an estimated 100 kg N ha-1, and the emission amounted to 3.2 kg Nox-N ha-1 （12 d） and 1.8 kg N20-N ha-1 （5 d）. Series 2 was made towards the end of the dry season when the WFPS was less than 60%. In Series 2-1 after an application of 50 kg N ha-1, emissions were markedly less, amounting to 0.9 kg N ha 1 over 10 d. During both series when the soil was moist, emissions of Nox were larger than those of N2o. the emission of Nox appeared to be haphazard, with little time dependence, but there was a clear diurnal cycle for N2o, emphasising the need for continuous measurement procedures for both gases. these results suggest that agricultural production on CASS could be important sources of greenhouse gases and nitrogen practices will need to be optimised to reduce the offsite effects of atmospheric warming, acidification or nitrification. Many questions still remain unanswered such as the emissions during the soybean bean filling stage and crop residue decomposition, the longer-term losses following the fertiliser application and emissions from CASS under different land uses.

关键词： denitrification greenhouse gases nitrification nitrogen oxides nitrous oxide

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Acoustic Emission Monitoring and Microscopic Investigation of Cracks in ERCuNi Cladding

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Journal of Materials Science & technology 2003年第3期19卷 201-205页

作者： S.P.Lu o.Y.Kwon K.J.Lee t.b.Kim Department of Mechanical Engineering Inha University253 Yonghyun-dongInchon 402-751KoreaDepartment of Mechanical EngineeringInha University253 Yonghyun-dongInchon 402-751KoreaDepartment of Mechanical EngineeringInha University253 Yonghyun-dongInchon 402-751KoreaDepartment of Mechanical EngineeringInha University253 Yonghyun-dongInchon 402-751Korea

A corrosion resistant CuNi cladding was deposited on SM45C (equivalent to AISI1045) substrate by DC inverse arc welding. During the welding process, a three channel acoustic emission (AE) monitoring system was applied to detect the crack signals generating from both the cladding process and after cladding. Characteristics of the welding crack signal and noise signal had been analyzed systematically. based on the record time of the signal, the solidification crack and delayed crack were distinguished. by two-dimensional AE source location, the crack position was located, and then investigated by scanning electron microscopy (SEM). Results showed that the AE system could detect the welding crack with high sensitivity and the two-dimensional source location could accurately determine the crack position. Microstructures of the cladding and heat affected zone (HAZ) were examined. Dendrites in the cladding and coarse grains in the HAZ were found.

关键词： Cladding Acoustic emission monitoring Crack CuNi alloy

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Isolation and molecular characterization of entomopathogenic nematode,Heterorhabditis *** an arable land in Nigeria

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Journal of Integrative Agriculture 2021年第10期20卷 2706-2715页

作者： Fisayo Y.DARAMoLA osarenkhoe o.oSEMWEGIE Stephen o.oWA Samuel b.oRISAJo Evbuomwan IKPoNMWoSA Elizabeth t.ALoRI Department of Microbiology Landmark UniversityOmu Aran 370102Kwara StateNigeria Crop Protection Division Cocoa Research Institute of NigeriaIbadan 200257Oyo StateNigeria Department of Crop and Soil Sciences Landmark UniversityOmu Aran 370102Kwara StateNigeria

the occurrence of entomopathogenic nematodes(EPNs)in arable soil samples from Nigeria was investigated using baermann extraction tray and insect-bait(White’s trap)*** were tested for infectivity using the larvae of Galleria mellonella(greater moth)and tenebrio molitor(mealworm).the study revealed a new species of Heterorhabditis(Mt371593)in soil samples that were randomly collected from an arable farmland cultivated with cassava tMS-30572 at the teaching and Research Farm of Landmark University,*** of the internal transcribed spacer region(ItS)of the ribosomal DNA produced a nucleotide sequence of 933 base pairs(bp).A bLAStN search of Genbank showed that the sequence of the Nigerian isolate is identical at 99%similarity to that of Heterorhabditis *** *** test of the isolate showed 100%mortality against *** larvae within 48 h of exposure while only 80%mortality was recorded for *** after 1 week of *** is the first account of Heterorhabditis *** *** varying degrees of infectivity against mealworm and greater moth observed in this study proved that the Nigerian isolate of Heterorhabditis *** potentially be an attractive option in the management of insect pests of cash crops.

关键词： biological control EPNs Heterorhabditis sp. ribosomal DNA tenebrio molitor

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Viscoelastic modeling of the diffusion of polymeric pollutants injected into a pipe flow

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Acta Mechanica Sinica 2013年第2期29卷 166-178页

作者： t.Chinyoka o.D. Makinde Center for Research in Computational and Applied Mechanics University of Cape town Institute for Advanced Research in Mathematical Modeling and Computations Cape Peninsula University of Technology

this study focuses on the transient analysis of nonlinear dispersion of a polymeric pollutant ejected by an external source into a laminar pipe flow of a Newtonian liquid under axi-symmetric *** influence of density variation with pollutant concentration is approximated according to the boussinesq approximation and the nonlinear governing equations of momentum,pollutant concentration are obtained together with and oldroyd-b constitutive model for the polymer *** problem is solved numerically using a semi-implicit finite difference *** are presented in graphical form for various parameter values and given in terms of fluid velocity,pollutant concentration,polymer stress components,skin friction and wall mass transfer *** model can be a useful tool in understanding the dynamics of industrial pollution situations arising from improper discharge of hydrocarbon pollutants into,say,water *** model can also be quite useful for available necessary early warning methods for detecting or predicting the scale of pollution and hence help mitigate related damage downstream by earlier instituting relevant decontamination measures.

关键词： Axi-symmetric flow·Polymeric pollutant dispersion·oldroyd-b model buoyancy forces·Semi-implicit finite difference method

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Calculation of electric field–temperature (E, t) phase diagram of a ferroelectric liquid crystal near the SmA–SmC_α~* transition

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Chinese Physics b 2018年第3期27卷 444-450页

作者： F trabelsi H Dhaouadi o Riahi t othman Universite de tunis El-Manar Faculte des Sciences de TunisLaboratoire de physique de la matiere molle et de modelisation electromagnetique(LP3ME)Campus Universitaire Farhat Hached 2092 Tunis Tunisie

In this work we perform a theoretical calculation in order to reconstitute the （E-t） phase diagram of a chiral smectic liquid crystal in the vicinity of the SmA-SmCα＊ transition. this reconstruction is carried out on the basis of a thermo-dynamic calculation of the slope of the curve joining the SmC＊ domain and the unwound SmC＊. An empiric correction of the mean field term of Landau De-Gennes development is necessary to accomplish this reconstruction. thereafter, an experimental validation is performed to verify our calculations.

关键词： field-temperature phase diagram liquid orystal

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Vibrational resonance in a multistable system with position-dependent mass

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Communications in theoretical Physics 2023年第11期75卷 115-134页

作者： t o Roy-Layinde K A omoteso o t Kolebaje F o ogunmefun R A Fasasi J A Laoye U E Vincent Department of Physics Olabisi Onabanjo UniversityAgo-IwoyeOgun StateNigeria Department of Physics Adeyemi Federal University of EducationOndoNigeria Department of Physical Sciences Redeemer’s UniversityP.M.B.230EdeNigeria Department of Physics Lancaster UniversityLancaster LA14 YBUnited Kingdom

the occurrence of vibrational resonance(VR)in a dual-frequency-driven multistable system with a spatially varying mass modelling particle with position-dependent mass(PDM)and evolving in a one-dimensional symmetric periodic potential has been investigated and reported in this *** numerically compute and analyze the response amplitude,the effects of the PDM parameters(m0,a)on the potential structure,the occurrence of VR and the bifurcation of the equilibrium *** is shown that the PDM parameters,besides controlling VR,can induce unconventional resonance patterns through the variation of the potential well *** resonant states can be influenced through the cooperation of the PDM parameters and the external forcing leading the system from multiresonance state into single and double resonance *** contributions of the fixed rest mass m0 on the VR and the PDM-induced resonance are determined by threshold conditions imposed by the magnitude of the mass nonlinear strength a.

关键词： vibrations resonance position-dependent mass multistable oscillator dualfrequency force nonlinear systems

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the impact of alpha-fetoprotein (AFP), child-turcotte-pugh (CtP) score and disease staging on the survival of hepatocellular carcinoma (HCC) patients: a retrospective cohort from single oncology center

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oncology research 2025年第1期33卷 149-160页

作者： Nasser Mulla Yousef Katib Asim M Almughamsi Duaa S Alkhayat Mohamed Mosaad Samir t Alfotih Rawan Alaofi Department of Internal Medicine Faculty of Medicine Taibah University Madinah 42278 Saudi Arabia. Department of Radiology Faculty of Medicine Taibah University Madinah 42278 Saudi Arabia. Department of Surgery Faculty of Medicine Taibah University Madinah 42278 Saudi Arabia. Department of Endemic and Infectious Diseases Suez Canal University Ismailia 41522 Egypt. King Salman bin Abdulaziz Medical City Madinah 42311 Saudi Arabia. Prince Mohammed bin Abdulaziz Hospital Madinah 41511 Saudi Arabia.

background:Hepatocellular carcinoma (HCC) is the most common cause of cancer-related death in Saudi Arabia. our study aimed to investigate the patterns of HCC and the effect of tNM staging, Alfa-fetoprotein (AFP), and Child-turcotte Pugh (CtP) on patients' overall survival (oS).Methods:A retrospective analysis was conducted on 43 HCC patients at a single oncology center in Saudi Arabia from 2015 to 2020. All patients had to fulfill one of the following criteria: (a) a liver lesion reported as definitive HCC on dynamic imaging and/or (b) a biopsy-confirmed diagnosis.Results:the mean patient age of all HCC cases was 66.8 with a male-to-female ratio of 3.3:1. All patients were stratified into two groups: viral HCC (n = 22, 51%) and non-viral HCC (n = 21, 49%). Among viral-HCC patients, 55% were due to HbV and 45% due to HCV. Cirrhosis was diagnosed in 79% of cases. Age and sex did not significantly statistically differ in oS among viral and non-viral HCC patients (-value > 0.05). About 65% of patients had tumor size >5 cm during the diagnosis, with a significant statistical difference in oS (-value = 0.027). AFP was >400 ng/ml in 45% of the patients. there was a statistically significant difference in the oS in terms of AFP levels (-value = 0.021). A statistically significant difference was also observed between the CtP score and oS (-value = 0.02). CtP class b had the longest survival. bSC was the most common treatment provided to HCC patients followed by sorafenib therapy. there was a significant statistical difference in oS among viral and non-viral HCC patients (-value = 0.008).Conclusions:the most common predictors for oS were the underlying cause of HCC, AFP, and tumor size. being having non-viral etiology, a tumor size >5 cm, an AFP > 400 ng/mL, and a CtP score class C were all negatively associated with oS.

关键词： Alpha-fetoprotein (AFP) Child-turcotte-pugh Hepatocellular carcinoma Pattern Progression free survival

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