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Experimental evidence for heritable reproductive time in 2 allochronic populations of pine processionary moth

Insect Science 2017年第2期24卷 325-335页

作者： Manuela Branco maria-Rosa Paiva helena maria santos Christian Burban Carole Kerdelhue Centro de Estudos Florestais (CEF) Instituto Superior de Agronomia (ISA) Universidade de Lisboa (ULisboa) 1349-017 Lisboa Portugal CENSE Faculty of Sciences and Technology (FCT) Universidade Nova de Lisboa (UNL) 2829-516 Caparica Portugal INRA Centre de Bordeaux UMR1202 BIOGECO Cestas cedex France INRA Centre de Montpellier UMR CBGP F-34988 Montferrier-sur-Lez cedex France

Phenology allows organisms to overcome seasonally variable conditions through life-cycle adjustment. Changes in phenology can drastically modify the evolutionary tra- jectory of a population, while a shift in the reproductive time may cause allochronic differentiation. The hypothesis of heritable reproductive time was experimentally tested, by studying a unique population of the pine processionary moth Thaumetopoeapityocampa （Den. ＆ Schiff.） which has a shifted phenology, and however co-occurs with the typical population following the classical life cycle. When populations of both types were reared under controlled conditions, the reproductive time was maintained asynchronous, as ob- served in the field. The shifted population was manipulated in the laboratory to reproduce later than usual, yet the offspring emerged in the next year at the expected dates thus ＂com- ing back＂ to the usual cycle. Hybrids from crosses performed between the 2 populations showed an intermediate phenology. From the emergence times of parents and offspring, a high heritability of the reproductive time （h = 0.76） was observed. The offspring ob- tained from each type of cross was genetically characterized using microsatellite markers. Bayesian clustering analysis confirmed that hybrids can he successfully identified and separated from the parental genetic classes by genotyping. Findings support the hypothesis that, for this particular population, incipient allochronic speciation is due to a heritable shift in the reproductive time that further causes assortative mating and might eventually cause ecological adaptation/maladaptation in response to environmental changes.

关键词： allochronic speciation experimental crossings heritability phenology reproductive isolation Thaumetopoeapityocampa

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Characterization and Evaluation of Bond Strength of Dental Polymer Systems Modified with Hydroxyapatite Nanoparticles

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Journal of Materials Science and Chemical Engineering 2013年第7期1卷 13-23页

作者： Vitor César Dumont Rafael Menezes Silva Luiz Edmundo Almeida-Júnior Juan Pedro Bretas Roa Adriana maria Botelho maria helena santos Department of Dentistry Federal University of Vales do Jequitinhonha and Mucuri Diamantina Brazil Department of Dentistry Federal University of Vales do Jequitinhonha and Mucuri Diamantina Brazil Advanced Biomaterial Center-BioMat UFVJM Diamantina Brazil Department of Dentistry Federal University of Vales do Jequitinhonha and Mucuri Diamantina Brazil Advanced Biomaterial Center-BioMat UFVJM Diamantina Brazil Institute of Science and Technology UFVJM Diamantina Brazil

The study modifies an adhesive system with hydroxyapatite nanoparticles as load, characterizing it and evaluate the effectiveness of its bond to dental structure. The middle thirds of healthy premolar tooth crowns were obtained, and each crown was sectioned vertically, resulting in two sections. The sections were divided into ten groups (n = 15), in which resin composite restorations were simulated: (G1E and G1D) conventional adhesive system (SAC);(G2E and G2D) SAC modified with HAP;(G3E and G3D) Primer modified with HAP;(G4E and G4D) monocomponent adhesive system;(G5E and G5D) self-etching adhesive system. The specimens were submitted to the microshear test and characterization technique. There was statistically significant difference (Kruskal-Wallis) between the groups (p 0.01). G3 presented the highest bond strength to enamel (64.40 MPa, ±7.36) and dentin (39.59 MPa, ±21.46). The majority of specimens were found adhesive fractures. Bond strength to enamel and dentin of the primer modified with HAP of SAC showed higher values.

关键词： Nanostructures Composites Mechanical Properties Fracture

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Bond Strength of Brackets Bonded with Chemically and Light Activated Materials after Thermal Cycling

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Advances in Materials Physics and Chemistry 2015年第9期5卷 351-360页

作者： Rafael Menezes-Silva Leonardo Amaral dos Reis Bhenya Otonni Tostes Dhelfeson Willyan Douglas de Oliveira maria helena santos Department of Dentistry Endodontics and Dental Materials Bauru Dental School University of Sao Paulo—USP Bauru Brazil Department of Pathology Piracicaba Dental School University of Campinas—UNICAMP Piracicaba Brazil Department of Dentistry Federal University of Minas Gerais—UFMG Belo Horizonte Brazil Department of Dentistry Federal University of the “Vales do Jequitinhonha e Mucuri”—UFVJM Diamantina Brazil

The aim of this study was to evaluate the bond strength of orthodontic brackets bonded to tooth enamel with different polymer composites after simulated clinical aging, and analyze the enamel/ bond system fracture interface. 80 human premolars, were randomly divided into five groups (n = 16). G1: CO (Concise Ortodontica—3M ESPE), G2: SB (SuperBond—Ortho Source), G3: FMO (Fill Magic Ortodontico—Vigodent), G4: TXT (Transbond XT—3M ESPE) and G5: TP (Transbond Plus Self Etching Primer + Transbond Plus Color Change—3M ESPE). In all groups, the metal orthodontic bracket was bonded to the tooth enamel surface. The specimens were submitted to 3000 thermal cycling baths for 30 s, at temperatures of 5°C, 37°C and 55°C (±1°C). Afterwards they were subjected to shear testing and the results were analyzed by the Student’s-t test (p G5 > G2 > G3. In all groups the majority of the fractures at the interface of the specimens were cohesive, except in G3, which presented the largest number of adhesive fractures. After clinical aging, the chemically activated material (CO) showed higher bond strength than the light activated types (FMO, TXT and TP). The self-etching adhesive system (TP) showed similar bond strength to that of conventional systems (FMO and TXT).

关键词： Dental Bonding Orthodontic Brackets Orthodontics

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Fatigue Strength Evaluation of Resin-Injected Bolted Connections Using Statistical Analysis

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Engineering 2017年第6期3卷 795-805页

作者： Jose Antonio Fonseca de Oliveira Correia Bruno Alexandre Silva Pedrosa Patricia Cordeiro Raposo Abilio Manuel Pinho De Jesus helena maria dos santos Gervisio Grzegorz Stanislaw Lesiukc Carlos Alberto da Silva Rebelo Rui Artur Bartolo Calcada Luis Alberto Proenca Simoes da Silva Faculty of Engineering University of Porto Porto 4200-465 Portugal Institute for Sustainability and Innovation in Structural Engineering (ISISE) Department of Civil Engineering University of Coimbra Coimbra 3030-788 Portugal Department of Mechanics Materials Science and Engineering Faculty of Mechanical Engineering Wroclaw University of Technology Wroctaw 50-370 Poland

Different strategies can be used to perform reparations and reinforcements of ancient bolted and riveted metallic bridges. As the riveting process is not currently a common practice, it requires proper equipment and skilled workers. Another solution is the use of welding. However, the weldability of old steels is poor. Bolts are very attractive alternative solutions, and are most commonly used to repair old metallic bridges. Fitted bolts are expensive solutions; the alternative is the use of resin-injected bolts. The behavior of bolted joints with preloaded resin-injected bolts has been studied using quasi-static and creep tests; however, few studies on the slip and fatigue behavior of these joints can be found in the literature. This paper presents an overview of a few experimental programs that were carried out by several authors aiming at evaluating the fatigue behavior of single and double shear resin-injected bolted connections. A comparison between the experimental data of joints with preloaded standard bolts and preloaded resin- injected bolts shows a fatigue strength reduction in the latter. Since Eurocode 3 （EC3） suggests the same fatigue strength curve for joints made of resin-injected bolts and standard bolts, this may raise some con- cerns. Furthermore, research on the feasibility of using both bonded and bolted connections is shown. This last study was performed with high-strength low-alloy structural steel plates and an acrylic struc- tural adhesive for metal bonding. For both case studies, a statistical analysis is performed on fatigue experimental data using linearized boundaries and the Castillo and Fernandez-Canteli model. Fatigue design curves are proposed and compared with the design suggestions of several European and North American standards,

关键词： Fatigue Connections Structural reinforcements Structural adhesives S-N curves Resin-injected bolts

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Liquefaction of Kraft Lignin at Atmospheric Pressure

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Journal of Renewable Materials 2019年第6期7卷 527-534页

作者： Silvia helena Fuentes da Silva Patricia Soares Bilhalva dos santos Darci Alberto Gatto maria Angeles Andres Itziar Egüés Chemical and Environmental Engineering Department University of Basque CountryPlaza Europa 120018Donostia-San SebastiánSpain Faculty of Forestry Engineering Federal University of ParáC.JoséPorfirio2515AltamiraBrazil College of Material Engineering(PPGCEM) Federal University of PelotasBrazil

Kraft lignin was liquefied using polyethylene glycol#400(PEG)and glycerol(G)in a weight ratio of 80/20(w/w)and sulphuric acid(SA)as catalyst under atmospheric pressure at 160º*** three independent variables:reaction time(60,80 and 100 min),percentage of lignin(15,20 and 25%,w/w),and catalyst concentration(0,3 and 6%,w/w),were varied resulting in 27 experimental *** effect of these reaction conditions on the properties of the polyols was *** statistical analysis showed that only“the percentage of lignin”did not influence the properties of the liquefied products,however,reaction time and catalyst load were important *** resulting liquefied products were characterized by FTIR analysis.

关键词： Biopolyols Kraft lignin liquefaction renewable resource thermochemical conversion

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Siderophore-Producing Rhizobacteria as a Promising Tool for Empowering Plants to Cope with Iron Limitation in Saline Soils:A Review

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Pedosphere 2019年第4期29卷 409-420页

作者： maria J.FERREIRA helena SILVA Angela CUNHA Biology Department and Centre for Environmental and Marine Studies(CESAM) University of Aveiro Campus de Santigo

Iron(Fe) bioavailability to plants is reduced in saline soils;however, the exact mechanisms underlying this effect are not yet completely understood. Siderophore-expressing rhizobacteria may represent a promising alternative to chemical fertilizers by simultaneously tackling salt-stress effects and Fe limitation in saline soils. In addition to draught, plants growing in arid soils face two other major challenges: high salinity and Fe deficiency. Salinity attenuates growth, affects plant physiology, and causes nutrient imbalance,which is, in fact, one of the major consequences of saline stress. Iron is a micronutrient essential for plant development, and it is required by several metalloenzymes involved in photosynthesis and respiration. Iron deficiency is associated with chlorosis and low crop productivity. The role of microbial siderophores in Fe supply to plants and the effect of plant growth-promoting rhizobacteria(PGPR) on the mitigation of saline stress in crop culture are well documented. However, the dual effect of siderophore-producing PGPR, both on salt stress and Fe limitation, is still poorly explored. This review provides a critical overview of the combined effects of Fe limitation and soil salinization as challenges to modern agriculture and intends to summarize some indirect evidence that argues in favour of siderophore-producing PGPR as biofertilization agents in salinized soils. Recent developments and future perspectives on the use of PGPR are discussed as clues to sustainable agricultural practices in the context of present and future climate change scenarios.

关键词： aridity bioavailability biofertilizer Fe deficiency high salinity plant growth-promoting rhizobacteria(PGPR) saline stress soil salinization

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Development and characterization of 3CaO·P_(2)O_(5)-SiO_(2)-MgO glass-ceramics with different crystallization degree

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Journal of Advanced Ceramics 2013年第4期2卷 378-388页

作者： Juliana Kelmy M.F.DAGUANO Paulo A.SUZUKI Kurt STRECKER JoséMartinho Marques de OLIVEIRA maria helena Figueira Vaz FERNANDES Claudinei santos Universidade de São Paulo-Escola de Engenharia de Lorena USP-EEL-Pólo Urbo-Industrials/nGleba AI-6Lorena-SPCEP 12600-000Brazil Universidade Federal de São João del-Rei -UFSJ-CENENCampus S^(to)Antônio-Praça Frei Orlando 170-CentroS.J.del-Rei-MG.CEP 36307-352Brazil Escola Superior Aveiro Norte Edifício Rainha3720-232 O.AzeméisPortugal Universidade de Aveiro Campus Universitário de Santiago 3810-193 AveiroPortugal Universidade do Estado do Rio de Janeiro-Faculdade de Tecnologia de Resende-UERJ-FAT-Rod.Presidente Dutra km298Resende-RJCEP 27537-000Brazil

The CaO-P_(2)O_(5)-SiO_(2)-MgO system presents several compounds used as biomaterials such as hydroxyapatite(HA),tricalcium phosphate(TCP)and TCP with magnesium substituting partial calcium(TCMP).Theβ-TCMP phase with whitlockite structure has interesting biological features and mechanical properties,meeting the requirements of a bioactive material for bone *** this work,the production of Mg-doped TCP,β-TCMP,has been investigated by crystallization from a glass composed of 52.75 wt%3CaO·P_(2)O_(5),30 wt%SiO_(2)and 17.25 wt%MgO(i.e.,31.7 mol%CaO,10.6 mol%P_(2)O_(5),26.6 mol%MgO and 31.1 mol%SiO_(2))using heat treatments between 775℃and 1100℃for up to 8 *** devitrification process of the glass has been accompanied by differential scanning calorimetry(DSC),high-resolution X-ray diffraction(HRXRD),relative density and bending strength *** characterization by HRXRD and DSC revealed the occurrence of whitlockite soon after the bulk glass preparation,a transient non-cataloged silicate between 800℃and 1100℃,and the formation of diopside in samples treated at 1100℃as crystalline *** overall crystalline fraction varied from 26%to 70%depending on the heat ***,contraction of the a-axis lattice parameter and expansion of the c-axis lattice parameter of the whitlockite structure have been observed during the heat treatments,which were attributed to theβ-TCMP formation with the partial substitution of Ca^(2+)by Mg^(2+).Relative densities near 99%and 97%for the glass and glass-ceramics respectively indicated a discrete reduction as a function of the devitrification *** strengths of 70 MPa and 120 MPa were determined for the glass and glass-ceramic material crystallized at 975℃for 4 h,respectively.

关键词： glass-ceramics heat treatment high-resolution X-ray diffraction(HRXRD) bending strength

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Survival predictors in patients treated with a molecular adsorbent recirculating system

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World Journal of Gastroenterology 2009年第24期15卷 3015-3024页

作者： Taru Kantola Anna-maria Koivusalo Satu Parmanen Krister Hckerstedt helena Isoniemi Department of Anesthesiology and Intensive Care Medicine Surgical Hospital of HelsinkiHelsinki University Central Hospital Department of Mathematics and Statistics University of Helsinki Transplantation and Liver Surgery Clinic Helsinki University Central Hospital

AIM:To identify prognostic factors for survival in patients with liver failure treated with a molecular adsorbent recirculating system(MARS). METHODS:MARS is a liver-assisting device that has been used in the treatment of liver failure to enable native liver recovery,and as a bridge to liver transplantation(LTX).We analyzed the 1-year outcomes of 188 patients treated with MARS,from 2001 to 2007, in an intensive care unit specializing in liver disease. Demographic,clinical and laboratory parameters were recorded before and after each ***-year survival and the number of LTXs were *** regression analysis was performed to determine factors predicting survival. RESULTS:The study included 113 patients with acute liver failure(ALF),62 with acute-on-chronic liver failure(AOCLF),11 with graft failure(GF),and six with miscellaneous liver *** was performed for 29% of patients with ALF,18% with AOCLF and 55%with *** overall 1-year survival rate was 74% for ALF,27% for AOCLF,and 73% for *** poorest survival rate,6%,was noted in non-transplanted patients with alcohol-related AOCLF and cirrhosis,whereas,patients with enlarged and steatotic liver had 55% *** etiology of liver failure was the most important predictor of survival(P<0.0001).Other prognostic factors were encephalopathy(P=0.001)in paracetamol-related ALF, coagulation factors(P=0.049)and encephalopathy(P=0.064)in non-paracetamol-related toxic ALF,and alanine aminotransferase(P=0.013)and factor V levels(P =0.022)in ALF of unknown etiology. CONCLUSION:The etiology of liver disease was the most important prognostic *** treatment appears to be ineffective in AOCLF with end-stage cirrhosis without an LTX option.

关键词： Molecular adsorbent recirculating system Prognostic factors Acute liver failure Acute-on-chronic liver failure Liver transplantation

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Iron homeostasis and H63D mutations in alcoholics with and without liver disease

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World Journal of Gastroenterology 2009年第1期15卷 106-111页

作者： mariana Verdelho Machado Paula Ravasco Alexandra Martins maria Rosário Almeida maria Ermelinda Camilo helena Cortez-Pinto Unidade de Nutrio e Metabolismo Instituto de Medicina Molecular Faculdade de Medicina da Universidade de Lisboa1649-035 Departamento de Gastrenterologia do Hospital de Santa maria 1649-035 Lisboa Portugal Genomed Instituto de Medicina Molecular1649-035 Portugal

MM： To evaluate the prevalence of HFE gene mutation and indices of disturbed iron homeostasis in alcoholics with and without liver disease. METHODS： One hundred and fifty-three heavy drinkers （defined as alcohol consumption 〉 80 g/d for at least 5 years） were included in the study. These comprised 78 patients with liver disease [liver disease alcoholics （LDA）] in whom the presence of liver disease was confirmed by liver biopsy or clinical evidence of hepatic decompensation, and 75 subjects with no evidence of liver disease, determined by normal liver tests on two occasions [non-liver disease alcoholics （NLDA）], were consecutively enrolled. Serum markers of iron status and HFE C282Y and H63D mutations were determined. HFE genotyping was compared with data obtained in healthy blood donors from the same geographical area. RESULTS： Gender ratio was similar in both study groups. LDA patients were older than NLDA patients （52 ± 10 years vs 48 ± 11 years, P = 0.03）. One third and one fifth of the study population had serum transferrin saturation （TS） greater than 45% and 60% respectively. Serum iron levels were similar in both groups. However, LDA patients had higher TS （51 ± 27 vs 36 ± 13, P 〈 0.001） and ferritin levels （559 ± 607 ng/mL vs 159 ± 122 ng/mL, P 〈 0.001）, and lower total iron binding capacity （TIBC）（241 ± 88 μg/dL vs 279 ± 40 μg/dL, P = 0.001）. The odds ratio for having liver disease with TS greater than 45% was 2.20 （95% confidence interval （CI）： 1.37-3.54）. There was no difference in C282Y allelic frequency between the two groups. However, H63D was more frequent in LDA patients （0.25 vs 0.16, P = 0.03）. LDA patients had a greater probability of carrying at least one HFE mutation than NLDA patients （49.5% vs 31.6%, P = 0.02）. The odds ratio for LDA in patients with H63D mutation was 1.57 （95% CI： 1.02-2.40）. CONCLUSION： The present study confirms the presence of iron overload in alcoholics, which was more severe in the subset of subjects with liver disease,

关键词： Alcoholic liver disease Iron lIFE gene H63D Hemochromatosis

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What exists beyond cag A and vacA? Helicobacter pylori genes in gastric diseases

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World Journal of Gastroenterology 2015年第37期21卷 10563-10572页

作者： Débora Menezes da Costa Eliane dos santos Pereira Silvia helena Barem Rabenhorst Molecular Genetics Laboratory Department of Pathology and Forensic Medicine School of Medicine Federal University of Ceará

Helicobacter pylori(H. pylori) infection is present in more than half the world's population and has been associated with several gastric disorders, such as gastritis, peptic ulceration, and gastric *** clinical outcome of this infection depends on host and bacterial factors where H. pylori virulence genes seem to play a relevant role. Studies of cag A and vac A genes established that they were determining factors in gastric pathogenesis. However, there are gastric cancer cases that are cag A-negative. Several other virulence genes have been searched for, but these genes remain less well known that cag A and vac A. Thus, this review aimed to establish which genes have been suggested as potentially relevant virulence factors for H. pylori-associated gastrointestinal diseases. We focused on the cag-pathogenicity island, genes with adherence and motility functions, and ice A based on the relevance shown in several studies in the literature.

关键词： Helicobacter pylori Virulence genes Cagpathogenici

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