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Release the iron: does the infection of magnetotactic bacteria by phages play a role in making iron available in aquatic environments?

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Journal of Oceanology and Limnology 2021年第6期39卷 2063-2069页

作者： Igor TAVEIRA Dennis ABAZYLINSKI fernanda ABREU Instituto de Microbiologia Paulo de Góes Departamento de Microbiologia GeralUniversidade Federal do Rio de JaneiroRio de Janeiro 21941-902Brazil School of Life Sciences University of Nevada at Las VegasLas Vegas 94720USA

Magnetotactic bacteria(MTB)are ubiquitous prokaryotes that orient along magnetic field lines due to magnetosomes’biomineralization within the *** structures are ferrimagnetic organelles that impart a magnetic moment to the *** succeed in producing magnetosomes,MTB accumulate iron in(i)cytoplasm;(ⅱ)magnetosomes;and(ⅲ)nearby the *** has already been estimated that a single MTB has an iron content of 10 to 100-fold higher than Escherichia *** are the most abundant entity in oceans and are known for controlling nutrient flow such as carbon and nitrogen by viral shunt and *** current work addresses the putative role of phages that infect MTB on the iron biogeochemical *** phage infection in MTB hosts cause a biogenic iron fertilization-like event in localized microenvironments?Are phages critical players in driving magnetosome biomineralization genes(BGs)horizontal transfer?Further investigation of those events,including frequency of occurrence,is necessary to fully comprehend MTB’s effect on iron cycling in aqueous environments.

关键词： horizontal gene transfer iron biogeochemical cycle magnetotactic bacteria magnetosome biomineralization genes phages

Long-term Regional Dynamic Sea Level Changes from CMIP6 Projections

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Advances in Atmospheric Sciences 2021年第2期38卷 157-167页

作者： Bruno FERRERO Marcos TONELLI fernanda MARCELLO Ilana WAINER University of São Paulo São Paulo 05508120Brazil

Anthropogenic climate forcing will cause the global mean sea level to rise over the 21st ***,regional sea level is expected to vary across ocean basins,superimposed by the influence of natural internal climate ***,we address the detection of dynamic sea level(DSL)changes by combining the perspectives of a single and a multimodel ensemble approach(the 50-member CanESM5 and a 27-model ensemble,respectively,all retrieved from the CMIP6 archive),under three CMIP6 projected scenarios:SSP1-2.6,SSP3-7.0 and *** ensemble analysis takes into account four key metrics:signal(S),noise(N),S/N ratio,and time of emergence(ToE).The results from both sets of ensembles agree in the fact that regions with higher S/N(associated with smaller uncertainties)also reflect earlier *** DSL signal is projected to emerge in the Southern Ocean,Southeast Pacific,Northwest Atlantic,and the *** common for both sets of ensemble simulations show that while S progressively increases with increased projected emissions,N,in turn,does not vary substantially among the SSPs,suggesting that uncertainty arising from internal climate variability has little dependence on changes in the magnitude of external *** changes are greater and quite similar for the scenarios SSP3-7.0 and SSP5-8.5 and considerably smaller for the SSP1-2.6,highlighting the importance of public policies towards lower emission scenarios and of keeping emissions below a certain threshold.

关键词： dynamic sea level CMIP6 sea level rise signal-to-noise time of emergence

Prospects for bone marrow cell therapy in amyotrophic lateral sclerosis：how far are we from a clinical treatment？

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Neural Regeneration Research 2016年第8期11卷 1216-1219页

作者： fernanda Gubert Marcelo F.Satiago Instituto de Biofisica Carlos Chagas Filho Universidade Federal do Rio de Janeiro Rio de Ianeiro RJ Brasil

Amyotrophic lateral sclerosis（ALS） is a fatal neurodegenerative disease that causes progressive muscular atrophy and death within 3–5 years after its *** the significant advances in knowledge of ALS pathology,no effective treatment is ***,it is imperative to search for new alternatives to treat *** therapy,especially using bone-marrow cells,has showed to be very useful to protect the neural tissue in different brain disease or traumatic *** ALS,most published results show beneficial effects of the use bone marrow cells,especially mesenchymal stromal ***,until now,the best outcome extends animal＇s lifespan by only a few *** is essential to continue the search for a really effective therapy,testing different cells,routes and time-windows of *** the mechanisms that initiate and spread the degenerative process is also important to find out an effective ***,we discussed here some progresses that have been made using bone-marrow cell therapy as a therapeutic tool for ALS.

关键词： amyotrophic lateral sclerosis cell therapy bone-marrow mononuclear cells mesenchymal stromal cells neuroinflammation motor neurons

Regional validity of the parameters of a distributed runoff-erosion model in the semi-arid region of Brazil

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Science China(Technological Sciences) 2009年第11期52卷 3348-3356页

作者： SRINIVASAN Vajapeyam Srirangachar PAIVA fernanda Maria de Lima Federal University of Campina Grande Post-graduate programme in Civil and Environmental Engineering Campus I 58429-900 Campina Grande PB Brazil

The present paper examines the validity of the application of a distributed rainfall-runoff-erosion model on a regional basis in a semi-arid region of Brazil. The model tested is known as WESP (Water Erosion Simulation Program) developed by Lopes (1987). The model simulates the hydrograph and the sediment graph for individual events and thus, the model when properly calibrated can serve as a predictive tool for runoff and soil erosion on an individual or a continuous basis. The possibility of the existence of regionally applicable values for the parameters of the model WESP would be very interesting from the point of view of predictability of runoff and soil erosion from ungauged basins in the region. For this purpose, data collected in several experimental units in the experimental basin of Sumé as well as in the experimental basin of So Joo de Cariri have been used. The model was calibrated and validated in each of the experimental units (consisting of erosion plots and micro-basins) and the average value from all of the units for each of the parameters was considered to be the regional value. With these average values, all the events in all the experimental units were simulated. The results show that the runoff and erosion values simulated with this single parameter set were very good in all the units, being well within the acceptable deviations.

关键词： regional parameters model WESP experimental basins semi-arid region soil erosion

Mind the gap among patches in arid plant communities:rapid root proliferation in response to N addition

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Journal of Plant Ecology 2019年第1期12卷 89-95页

作者： Maria fernanda Reyes Martín RAguiar Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura(IFEVA)and Consejo Nacional de Investigaciones Científicas y Técnicas(CONICET) Universidad de Buenos AiresAv.San Martín 4453Buenos Aires C1417DSEArgentina

Aims In arid communities,it has been proposed that individual plants can extend their roots beyond their canopy exploring neighbour-ing bare ground *** becomes relevant in systems where the vegetation is distributed in patches surrounded by bare ***,whether roots of different species may be overlapping under bare ground areas is still *** factors control-ling root responses when no plants appear to be directly influ-encing the gap among patches are still *** aim of our study was to detect perennial grasses responses to an N enrich-ment *** In a semi-arid steppe(Patagonia,Argentina),we buried root traps filled with sieved soil with and without N addition,under bare soil *** were harvested after 4 and 6 *** neighbour-hoods(30 cm in diameter)included at least three of the dominant tussock *** harvests,we identified species in the traps by root traits and quantified diversity,biomass and specific relative growth *** Findings Bare ground areas show simultaneous root growth of different *** of perennial grass roots was higher with N addition than without it in the first harvest(4 months),but this difference disappeared in the second harvest(6 months).Root biomass was maximal after 6 months in N addition *** preferred by herbivores(Bromus pictus and Poa ligularis)showed rapid growth and responses to N *** between harvests may be an indicative that N pulses interact with rising temperatures and soil water content as growing season progress.

关键词： belowground community ecology grass species roots Patagonian steppe patchiness root growth rates zone of influence

Nanosized magnetite in low cost materials for remediation of water polluted with toxic metals, azo- and antraquinonic dyes

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Frontiers of Environmental Science & Engineering 2015年第5期9卷 746-769页

作者： Maria fernanda HORST Veronica LASSALLE Maria Lujan FERREIRA Institute of Chemistry of the South (Inquisur Universidad Nacional del Sur~ONICET) Avda Alem 1253 Bahia Blanca Argentina Pilot Plant of Chemical Engineering (PLAPIQUI-UNS-CONICET) Universidad Nacional del Sur--CONICET Camino La Carrindanga km7 Bahia Blanca Argentina

Nanosized magnetite has emerged as an adsorbent of pollutants in water remediation. Nanoadsor- bents include magnetic iron oxide and its modifiers/ stabilizers, such as carbon, silica, clay, organic moieties （polymers, aminoaeids, and fatty acids） and other inorganic oxides. This review is focused on the recent developments on the synthesis and use of magnetic nanoparticles and nanocomposites in the treatment of contaminated water. The emphasis is on the influence of the iron oxide modifiers on some properties of interest such as size, BET area, and magnetization. The characteristics of these nanomaterials are related to their ability to eliminate heavy metal ions and dyes from wastewater. Comparative analysis of the actual literature was performed aiming to present the magnetic material, its preparation methodology and performance in the elimination of the selected pollutants. Vast information has been properly summarized according to the materials, their properties and preferential affinity for selected contaminants. The mechanisms governing nanomaterial＇s formation as well as the interactions with heavy metals and dyes have been carefully analyzed and associated to their efficiency.

关键词： nanomagnetite water remediation toxicmetals dyes supported magnetite

Hyaluronic acid association with bacterial,fungal and viral infections:Can hyaluronic acid be used as an antimicrobial polymer for biomedical and pharmaceutical applications?

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Bioactive Materials 2023年第1期19卷 458-473页

作者： fernanda Zamboni Chun Kwok Wong Maurice N.Collins Bernal Institute School of EngineeringUniversity of LimerickIreland Health Research Institute University of LimerickIreland Department of Chemical Pathology The Chinese University of Hong KongHong Kong Special Administrative Region

The relationships between hyaluronic acid(HA)and pathological microorganisms incite new understandings on microbial infection,tissue penetration,disease progression and lastly,potential *** understandings are important for the advancement of next generation antimicrobial therapeutical strategies for the control of healthcare-associated ***,this review will focus on the interplay between HA,bacteria,fungi,and *** review will also comprehensively detail and discuss the antimicrobial activity displayed by various HA molecular weights for a variety of biomedical and pharmaceutical applications,including microbiology,pharmaceutics,and tissue engineering.

关键词： Hyaluronic acid Hyaluronidase Virulence Antibacterial Antifungal Antiviral

DroidEnemy: Battling adversarial example attacks for Android malware detection

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Digital Communications and Networks 2022年第6期8卷 1040-1047页

作者： Neha Bala Aemun Ahmar Wenjia Li fernanda Tovar Arpit Battu Prachi Bambarkar Department of Computer Science New York Institute of TechnologyNew YorkNY10023USA

In recent years,we have witnessed a surge in mobile devices such as smartphones,tablets,smart watches,etc.,most of which are based on the Android operating ***,because these Android-based mobile devices are becoming increasingly popular,they are now the primary target of mobile malware,which could lead to both privacy leakage and property *** address the rapidly deteriorating security issues caused by mobile malware,various research efforts have been made to develop novel and effective detection mechanisms to identify and combat ***,in order to avoid being caught by these malware detection mechanisms,malware authors are inclined to initiate adversarial example attacks by tampering with mobile *** this paper,several types of adversarial example attacks are investigated and a feasible approach is proposed to fight against ***,we look at adversarial example attacks on the Android system and prior solutions that have been proposed to address these ***,we specifically focus on the data poisoning attack and evasion attack models,which may mutate various application features,such as API calls,permissions and the class label,to produce adversarial ***,we propose and design a malware detection approach that is resistant to adversarial *** observe and investigate how the malware detection system is influenced by the adversarial example attacks,we conduct experiments on some real Android application datasets which are composed of both malware and benign *** results clearly indicate that the performance of Android malware detection is severely degraded when facing adversarial example attacks.

关键词： Security Malware detection Adversarial example attack Data poisoning attack Evasi on attack Machine learning Android

Magnitude of the contralateral efferent olivocochlear effect as a function of the frequency

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Journal of Otology 2022年第2期17卷 67-71页

作者： fernanda Anza Miranda Enzo Aguilar-Vidal Laboratorio de Audiología y Percepcion Auditiva Facultad de MedicinaUniversidad de ChileChile Escuela de Tecnología Medica Facultad de MedicinaUniversidad de ChileChile Departamento de Tecnología Medica Facultad de MedicinaUniversidad de ChileChile

Background:The activation of the medial olivocochlear reflex reduces the cochlear gain,which is manifested perceptually as decreased auditory ***,it has remained unclear whether the extent of this suppression varies according to the cochlear region *** we aims to assess the magnitude of contralateral efferent suppression across human cochlea,at low levels,and its impact on hearing ***:Assuming that acoustic stimulation activates the contralateral medial olivocochlear reflex,we evaluated the magnitude of the suppressive effect as a function of frequency in 17 subjects with normal *** thresholds were measured for bursts tones of various durations(10,100,and 500 ms)and frequencies(250,500,1000,4000,and 8000 Hz)in the presence or absence of contralateral white noise at 60 d B ***:We found that contralateral noise raised the absolute threshold for the burst tones *** effect was greater at lower than higher frequencies(3.85 d B at 250 Hz vs.2.22 d B at 8000 Hz).Conclusions:Our findings suggest that in humans,the magnitude of this suppression varies according to the cochlear region stimulated,with a greater effect towards the apex(lower frequencies)than the base(higher frequencies)of the cochlea.

关键词： Auditory perception Efferent system Medial olivocochlear reflex Absolute threshold