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Marigold(Tagetes erecta): The Potential Value in the Phytoremediation of Chromium

Pedosphere 2017年第3期27卷 559-568页

作者： Lívia C.COELHO Ana Rosa R.BASTOS paulo j.pinho Guilherme A.SOUZA janice G.CARVALHO Viviane A.T.COELHO Luiz Carlos A.OLIVEIRA Rimena R.DOMINGUES Valdemar FAQUIN Soil Science Department Federal University of Lavras Chemistry Department Federal University of Minas Gerais

Environmental pollution with chromium （Cr） is harmful to humans, animals and plants, while in plants it causes diminished growth, anatomical alterations and death. In the present study, the potential value of marigold （Tagetes erecta） in the phytoremediation of Cr has been investigated. The randomized experimental design involved the exposure of plants to nutrient solutions containing 0.00, 0.04, 0.08, 0.12, 0.16 or 0.24 mmol L-1 Cr（III）. Chromium toxicity was observed at Cr（III） concentrations ≥ 0.12 mmol L-1 as demonstrated by diminished growth of the aerial parts and reduced density of the root system. Increasing Cr（III） concentrations in the nutrient solution resulted in a higher bioaccumulation of total Cr in the tissues, although translocation from roots to aerial parts was not efficient （maximum value of 25% at 0.12 mmol L-1 Cr（III））. The Cr bioaccumulation was up to 11-fold greater in roots than in the aerial parts. Tagetes erecta exhibited leaf plasticity when exposed to Cr, indicating the existence of a tolerance mechanism to Cr in this species. Chromium caused a reduction in xilem vases, resulting in a plastic effect in T. erecta leaves that increased the metal tolerance in culture solution. Tagetes spp. are potential Cr hyperaccumulators; at Cr（III） concentrations up to 0.12 mmol L-1, the plants accumulated levels above that proposed for hyperaccumulators and still maintained a considerable growth and even flourished. However, this study was conducted in nutrient solution, and studies on species confirmation as Cr hyperaccumulator should be conducted in soils for further clarification.

关键词： anatomical alterations heavy metal hyperaccumulor leaf anatomy toxicity

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Landslide susceptibility mapping using the infinite slope,SHALSTAB,SINMAP,and TRIGRS models in Serra do Mar,Brazil

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journal of Mountain Science 2022年第4期19卷 1018-1036页

作者： Thiago Machado do pinho Oswaldo AUGUSTO FILHO University of Sao paulo Sao CarlosSP13566-590Brazil

Slope failure triggered by heavy rainfall is very common in tropical and subtropical regions and a cause of major social and economic *** susceptibility maps can be generated using geographical information systems(GIS)and limit equilibrium slope stability models coupled or not to hydrological *** study investigated the efficacy of four models used for slope stability analysis in predicting landslide-susceptible areas in a GIS *** selected models are the infinite slope,the shallow slope stability model(SHALSTAB),the stability index mapping(SINMAP),and the transient rainfall infiltration and grid-based regional slope-stability(TRIGRS).For comparisons,the authors(a)included the infinite slope equation in all models,(b)clearly defined input parameters and failure triggering mechanisms for each simulation(soil depth,water table height,rainfall intensity),(c)determined appropriate values for each model to obtain stability levels that represented similar hydrogeotechnical conditions,and(d)considered upper-third areas of landslide scars to estimate the reliability of susceptibility maps using validation *** intense rainfall event occurred in Serra do Mar,Brazil in january 2014 triggered hundreds of landslides and was used for back analysis and evaluation of the slope stability analysis *** rainfall intensity is not considered,the four models produced very similar *** most reliable landslide susceptibility map was generated using TRIGRS and considering the granite residual granite soils geological-geotechnical unit,subjected to a rainfall intensity of 210 mm for 2 h under unsaturated conditions.

关键词： Geographical information system Safety factor Heavy rainfall Geomechanical parameters Residual soils of phyllite and granite Serra do Mar

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Analysis of Surface Integrity in Drilling Metal Matrix and Hybrid Metal Matrix Composites

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journal of Materials Science & Technology 2012年第8期28卷 761-768页

作者： T.Rajmohan K.Palanikumar j.paulo Davim Department of Mechanical Engineering Sri Chandrasekharendra Saraswathi Viswa Maha Vidyalaya University Department of Mechanical Engineering Sri Sai Ram Institute of Technology Department of Mechanical Engineering University of AveiroCampus Santiago3810-193 AveiroPortugal

Hybrid metal matrix composites consist of at least three constituents-a metal or an alloy matrix and two reinforcements in various forms, bonded together at the atomic level in the composite. Despite their higher specific properties of strength and stiffness, the non homogeneous and anisotropic nature combined with the abrasive reinforcements render their machining difficult. In this paper, the surface integrity of machining in drilling hybrid composites has been discussed. Drilling tests are carried out at different spindle speed, feed rates, and different drill tool materials to investigate the effect of the various cutting parameters on the surface quality and the extent of the deformation of drilled surface due to drilling. Materials used for the present investigation are A1356/IOSIC （wt%） metal matrix and A1356/10SiC-3mica （wt%） hybrid composites. The composites are fabricated using stir casting route. The drilling tests are conducted on vertical computer numeric control （CNC） machining center using carbide, coated carbide and polycrystalline diamond （PCD） drills. The surface roughness decreases with increasing spindle speed and increases with increasing feed rate. The machined surface is analyzed by scanning electron microscopy （SEM）. SEM images of the machined surfaces indicate the presence of grooves and pits. Microhardness depth profiles indicate that the subsurface damage is limited to the top of 100-250 μm.

关键词： Hybrid composites Scanning electron microscopy (SEM) Subsurface Drilling

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Germination strategies of annual and short-lived perennial species in the Arabian Desert

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journal of Arid Land 2020年第6期12卷 1071-1082页

作者： Arvind BHATT David j GALLACHER paulo R M SOUZA-FILHO Lushan Botanical Garden Chinese Academy of SciencesJiujiang 332900China School of Life and Environmental Sciences The University of SydneyNarrabri NSW 2390Australia Multidisciplinary Center of Barra Federal University of Western BahiaBarra 47100-000Brazil

Germination timing is highly regulated in short-lived plant species since it strongly influences recruitment success of *** deserts,the spatiotemporal distribution of plant-available water is highly episodic and unpredictable,making winter months more favorable for seed germination when other abiotic conditions *** hypothesized that changes in photoperiod and thermoperiod would impact germination more in seeds that had undergone in situ *** assessed 21 annual and short-lived perennial species in the Arabian Desert to find(1)if seeds were dormant at maturity,(2)if in situ seed storage increased germination percentage compared with no storage,(3)if photoperiod and thermoperiod germination requirements were influenced by in situ storage,and(4)if a phylogenetic association in seed germination could be *** of each species collected in early 2017 were divided into two *** was tested for germination within one week(fresh seeds).The other was stored in situ at the maternal location(stored seeds)until October 2017 and tested for seed germination in the first week of *** germination was conducted in incubators at two thermoperiods(15℃/20℃ and 20℃/30℃;12 h/12 h),and two photoperiods(12 and 0 h light per day).Results indicated that seed germination percentages of 13 species were significantly enhanced by in situ storage.A thermoperiod response was exhibited by stored,but not fresh *** exposure increased germination of fresh seeds but had only a minimal effect on stored *** traits exhibited no phylogenetic *** result indicated that selection pressure for germination strategy was stronger than that for taxonomic traits of these desert species.

关键词： desert species dormancy germination light temperature phylogeny

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Assessment of mercury(II) bioavailability using a bioluminescent bacterial biosensor: Practical and theoretical challenges

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journal of Environmental Sciences 2010年第8期22卷 1137-1143页

作者： paulo R G Barrocas William M Landing Robert j M Hudson Department of Sanitation and Environmental Health National School of Public Health Oswaldo Cruz Foundation Department of Oceanography Florida State University. Tallahassee Department of Natural Resources and Environmental Sciences University of Illinois

Critical methodological challenges in the microbial biosensor approach to assessing Hg（II） bioavailability were evaluated from the perspective of analytical chemists. The main challenge stems from the fact that the chemical speciation of Hg（II） in natural waters exerts a major control on its bioavailability, yet its natural complexation equilibria are extensively altered during conventional bioassays. New data, obtained using a bioluminescent Hg（II）-biosensor, that illustrate these challenges are presented and potential solutions proposed.

关键词： mercury bioavailability biosensor chemical speciation bioluminescent

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Nicotinic cholinergic receptors in esophagus:Early alteration during carcinogenesis and prognostic value

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World journal of Gastroenterology 2016年第31期22卷 7146-7156页

作者： Marina Chianello Nicolau Luis Felipe Ribeiro Pinto Pedro Nicolau-Neto paulo Roberto Alves de pinho Ana Rossini Tatiana de Almeida Simao Sheila Coelho Soares Lima Departamento de Bioquímica Instituto de Biologia Roberto Alcantara GomesUniversidade do Estado do Rio de Janeiro Programa de Carcinogênese Molecular Instituto Nacional de CancerCoordenacao de Pesquisa Gastroenterologia Hospital Universitário Pedro ErnestoUniversidade do Estado do Rio de Janeiro

AIM: To compare expression of nicotinic cholinergic receptors(CHRNs) in healthy and squamous cell carcinoma-affected esophagus and determine the prognostic ***: We performed RT-q PCR to measure the expression of CHRNs in 44 esophageal samples from healthy individuals and in matched normal surrounding mucosa, and in tumors from 28 patientsdiagnosed with esophageal squamous cell carcinoma(ESCC). Next, we performed correlation analysis for the detected expression of these receptors with the habits and clinico-pathological characteristics of all study participants. In order to investigate the possible correlations between the expression of the different CHRN subunits in both healthy esophagus and tissues from ESCC patients, correlation matrices were generated. Subsequently, we evaluated whether the detected alterations in expression of the various CHRNs could precede histopathological modifications during the esophageal carcinogenic processes by using receiver operating characteristic curve analysis. Finally, we evaluated the impact of CHRNA5 and CHRNA7 expression on overall survival by using multivariate ***: CHRNA3, CHRNA5, CHRNA7 and CHRNB4, but not CHRNA1, CHRNA4, CHRNA9 or CHRNA10, were found to be expressed in normal(healthy) esophageal mucosa. In ESCC, CHRNA5 and CHRNA7 were overexpressed as compared with patient-matched surrounding non-tumor mucosa(ESCC-adjacent mucosa; P jacent mucosa, allowing for distinguishment between these tissues with a sensitivity of 75.86% and a specificity of 78.95%(P = 0.0002). Finally, CHRNA5 expression was identified as an independent prognostic factor in ESCC; patients with high CHRNA5 expression showed an increased overall survival, in comparison with those

关键词： Nicotinic cholinergic receptors Esophagus Esophageal squamous cell carcinoma Tobacco Alcohol Gene expression

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A Quasilinear System Related with the Asymptotic Equation of the Nematic Liquid Crystal’s Director Field

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Chinese Annals of Mathematics,Series B 2021年第2期42卷 163-172页

作者： joão-paulo DIAS Departamento de Matemática and CMAFcIO Faculdade de Ciências da Universidade de LisboaCampo GrandeEdificio C61749-016 LisboaPortugal

In this paper, the author studies the local existence of strong solutions and their possible blow-up in time for a quasilinear system describing the interaction of a short wave induced by an electron field with a long wave representing an extension of the motion of the director field in a nematic liquid crystal’s asymptotic model introduced in[Saxton, R. A., Dynamic instability of the liquid crystal director. In: Current Progress in Hyperbolic Systems(Lindquist, W. B., ed.), Contemp. Math., Vol.100, Amer. ***., Providence, RI, 1989, pp.325–330] and [Hunter, j. K. and Saxton, R. A., Dynamics of director fields, SIAM j. Appl. Math., 51, 1991, 1498–1521] and studied in [Hunter, j. *** Zheng, Y., On a nonlinear hyperbolic variational equation I, Arch. Rat. Mech. Anal.,129, 1995, 305–353], [Hunter, j. K. and Zheng, Y., On a nonlinear hyperbolic variational equation II, Arch. Rat. Mech. Anal., 129, 1995, 355–383] and in [Zhang, P. and Zheng,Y., On oscillation of an asymptotic equation of a nonlinear variational wave equation,Asymptotic Anal., 18, 1998, 307–327] and, more recently, in [Bressan, A., Zhang, P. and Zheng, Y., Asymptotic variational wave equations, Arch. Rat. Mech. Anal., 183, 2007,163–185].

关键词： Benney system Conservation law Schrödinger equation Nematic liquid crystal Director field

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Rat cardiomyocyte H9c2(2-1)-based sulforhodamine B assay as a promising in vitro method to assess the biological component of effluent toxicity

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journal of Environmental Sciences 2020年第10期32卷 163-170页

作者： Elsa T Rodrigues Susana F Nascimento Maria joao Moreno paulo j Oliveira Miguel A Pardal University of Coimbra Centre for Functional EcologyDepartment of Life SciencesCalcada Martim de FreitasCoimbra 3000-456Portugal University of Coimbra Coimbra Chemistry CenterDepartment of ChemistryCoimbra 3004-535Portugal Centre for Neuroscience and Cell Biology Uniuersity of CoimbraUC BiotechBiocant ParkCantanhede 3060-197Portugal

The treatment of wastewaters is crucial to maintain the ecological status of receiving waters,and thereby guarantee the protection of aquatic life and human *** quality evaluation is conventionally based on physicochemical parameters,but increasing attention has been paid to integrate physicochemical and biological ***,the regulatory use of fish in biological testing methods has been subject to various ethical and cost concerns,and in vitro cell-based assays have thus become an important topic of ***,the present study intends:(a) to evaluate the efficiency of two different sample pre-concentration techniques (lyophilisation and solid phase extraction) to assess the toxicity of municipal effluents on rat cardiomyoblast H9c2(2-1) cells,and (b) maximizing the use of the effluent sample collected,to estimate the environmental condition of the receiving *** gathered results demonstrate that the H9c2(2-1) sulforhodamine B-based assay is an appropriate in vitro method to assess biological effluent toxicity,and the best results were attained by lyophilising the sample as *** to its response,the H9c2(2-1) cell line might be a possible alternative in vitro model for fish lethal testing to assess the toxicity of municipal *** physicochemical status of the sample suggests a high potential for eutrophication,and iron exceeded the permissible level for wastewater discharge,possibly due to the addition of ferric chloride for wastewater *** general,the levels of carbamazepine and sulfamethoxazole are higher than those reported for other countries,and both surpassed the aquatic protective values for long-term exposure.

关键词： Municipal wastewater treatment plant effluent Lyophilisation Solid phase extraction Cell-based assays H9c2(2-1)cell line SRB assay

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Annual variation of adult survival of a south-temperate House Wren population in Argentina

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Avian Research 2024年第2期15卷 229-237页

作者： Gustavo j.Fernandez Mariana E.Carro paulo E.Llambías Grupo de Investigacion en Ecofisiología de Fauna Silvestre INIBIOMA-CONICETAsentamiento Universitario San Martín de los Andes(AUSMA)Universidad Nacional Del ComahuePasaje de la Paz 235(8370)San Martín de los AndesNeuquenArgentina Grupo de Investigacion de Biología de Aves IADIZA CCT-MendozaUniversidad Nacional de CuyoAvenida RuizLeal s/n Parque General San Martin5500MendozaArgentina

Identifying factors affecting the survival of individuals is essential for understanding the evolution of life-history traits and population *** numerous studies on this subject in north-temperate environments,there is a lack of equivalent studies at similar latitudes in the ***,we used a 14-year dataset of capture,banding,and resighting to estimate the annual variation in the apparent adult survival probability of a south-temperate population of House Wrens(Troglodytes aedon bonariae).We evaluated temporal variation in sur-vival and the effect of environmental(climatic)and demographic variables(adult abundance,total number of fledglings produced during each breeding season)on survival *** found that the probability of adult survival decreased as the abundance of breeding adults *** density-dependent effect could be related to the resident lifestyle of southern House Wrens,which could determine an intense competition for territories and resources that ultimately would affect their survival.

关键词： Annual variation CjS Density-dependence Survival Troglodytes aedon bonariae

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Surgical treatment of Peyronie＇s disease： choosing the best approach to improve patient satisfaction

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Asian journal of Andrology 2008年第1期10卷 158-166页

作者： paulo H. Egydio Urology Institute Rua lguatemi 192 Cj. 42 Sao Paulo 01451-010 Brazil

Aim： To discuss important points on medical history, preoperative evaluation, real expectations, and selection of the appropriate surgical procedure to improve patient satisfaction after surgical procedures for Peyronie＇s disease. Methods： Recent advances in approaches to Peyronie＇s disease are discussed based on the literature and personal experiences. Issues concerning surgical indication, patient selection, surgical techniques, and grafting are discussed. Lengthening procedures on the convex side of the penile curvature by means of grafting offer the best possible gain from a reconstruction standpoint. Penile rectification and rigidity are required to achieve a completely functional penis. Most patients experience associated erectile dysfunction （ED）, and penile straightening alone may not be enough to restore complete function. Twenty-five patients were submitted to total penile reconstruction on length and girth with concomitant penile prosthesis implant. The maximum length restoration was possible and limited by the length of the dissected neurovascular bundle. The mean age was 55.4 years （32-69 years） and the mean angle of curvature 74.2± 22.4° （0-100°）. Pericardial grafting was used to cover the defect. The mean follow-up time was 11.2 ± 5.9 months （3-22 months）. Results： Mean functional penile length gain was 3.40 ＋ 0.73 cm （2-5 cm）. Penile prosthesis maintained the penis straight. No infections occurred. Sexual intercourse was restored in all patients and all reported recovered self-esteem. Conclusion： Improving patient satisfaction with the surgical treatment includes proper preoperative evaluation on stable disease, penile shortening, vascular and erectile status, patient decision and selection as well as extensive discussion on surgical technique for restoring functional penis （length and rigidity）. Length and girth restoration is very important for self-esteem and patient satisfaction.

关键词： Peyronie's disease erectile dysfunction induratio penis plastica penile induration tunica albuginea surgical technique penis graft surgery penile reconstruction

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