bluuebunny/crossref_metadata_2025 huggingface dataset:
Geochemical characterisation of Otumba obsidian sub-sources (Central Mexico) by inductively coupled plasma mass spectrometry and density-based spatial clustering of applications with noise statistical analysis
Authors: Argote-Espino Denisse , Solé Jesús , López-García Pedro , Sterpone Osvaldo
Published: January 2014

Several obsidian sources that were significant to the lithic industry all over Mesoamerica are contained in the Central Mexico highlands. Many archaeological investigations have suggested that the economical and political expansion of important Mesoamerican cultures was related to the control of obsidian sources and its commercial routes. One of these sources was Otumba, located west of the Teotihuacan Valley. This region has several sub-sources, some of which have been studied in more detail than others. The most studied subsource is the one located on Soltepec Hill, but other related sub-sources within Otumba region that have not been studied include the Ixtete, Pacheco, Malpais and Tepayo domes. We have analysed samples from these four sub-sources with inductively coupled plasma mass spectrometry (ICP-MS) method to determine their chemical similarities and differences and classify them. The individual correlation of different archaeological artifacts with each sub-source could tell us about exploitation preferences of the diverse cultures controlling the source or even sequence in time of its utilisation.
Non-destructive analysis of archaeological ochre: a preliminary application to the Middle Stone Age site of Diepkloof Rock Shelter (South Africa)
Authors: Dayet Laure , Daniel Floréal , Guibert Pierre , Texier Pierre-Jean
Published: January 2014

A number of ochre pieces were found from the Middle Stone Age (MSA) in southern Africa, leading to recent debates about the use of this material. The relevant question behind such a debate lies in the role of ochre in early modern human societies. Technical, socio-economical and symbolic aspects might be associated with ochre processing and use. Ochre pieces showing signs of use-wear found on MSA sites are the main witnesses of such activities. That is why our work has focused on the study of ochre pieces, especially on the issue of the raw material selection. The relevance of non-destructive methods in order to determine the mineralogical nature of ochre is discussed here. Scanning electron microscopyenergy- dispersive X-ray spectroscopy (SEM EDS) and X-ray diffraction (XRD) analyses were used. Based on careful considerations of the association of different features, such as the elementary composition or the fabric, we showed that under certain conditions surface analyses are very useful to assign samples into mineralogical categories.
A technological study on the 17th century raised gilded substrates in three royal palaces of Isfahan, Iran
Authors: Holakooei Parviz , Abed-Esfahani Abbas , Samanian Samad , Aslani Hesam
Published: January 2014

The raised substrates of gilding decorations, called lāyachīnīī in Persian, were widely used throughout the Safavid period (1501-1736 AD) in Iran. This paper presents the first analytical data obtained from the lāyachīnīs of three seventeenth century royal Safavid buildings (ʿAlī- Qāpū, Chihil-Sutūn, and Hasht-Bihisht) in Isfahan, Iran, using energy dispersive X-ray spectroscopy, scanning electron microscope, Xray powder diffraction, and thin layer chromatography. According to the analytical data, different forms of calcium sulfate (dihydrate, β-hemihydrate, and anhydrite), the red iron oxides, and a proteinaceous binder (probably animal glue) are the main constituents of the raised lāyachīnī substrates. The results show that a dry mixture of the plaster of Paris and the red iron oxides are mixed with diluted animal glue to obtain a slurry to be applied in several layers, one top of the another, to achieve the raised substrates. This technique is similar to those European raised pastiglia substrates although the method of the preparation in the Persian technique is different from the European one.
Technology, production, and distribution of terminal classic molded-carved vases in the Central Maya Lowlands
Authors: Ting Carmen , Helmke Christophe
Published: January 2014

The paper summarises the results of the technological and stylistic analyses of the moldedcarved ceramic vases from Altun Ha, and Pook’s Hill, two archaeological sites located in Belize. The stylistic analysis of these vases indicates that the decorative modes and the tradition of manufacturing vases by molds date squarely to the Terminal Classic period (ca. AD 800-1000). The Terminal Classic period is one of transition, exhibiting dramatic socio-political changes in the Maya Lowlands. The technological analyses employ energy dispersive X-ray fluorescence (ED-XRF), thin-section petrography, scanning electron microscopy-energy dispersive spectrometer (SEM-EDS), to characterise the physical, mineralogical, and chemical properties of the molded-carved vases. Combining the results of the technological and stylistic analyses help to discriminate the production groups, reconstruct the manufacturing technology, characterise the organisation of production, and delineate distribution patterns. Our present findings reveal that the changes in the socio-political order during the Terminal Classic in the Maya Lowlands likely stimulated changes in the types and manner in which elite pottery was produced, as well as the mechanisms responsible for the distribution of such ceramics.
Dispersion pattern and fixed precision sequential sampling of Sitobion avenae (Fabricus) (Hemiptera: Aphididae) in wheat fields of Badjgah (Fars province) in Iran
Authors: Soltani Ghasemloo V. , Aleosfoor M.
Published: January 2014

Understanding the dispersion pattern of a species is an important pre-requisite for developing an effective pest management program. In this study, four hundred wheat plants were surveyed for Sitobion avenae twice a week during 2010 and 2011 growing seasons in two fields of Badjgah (Fars province) in Iran. In each field only one of the two cultivers of Bahar or Shiraz was planted. Analysis of spatial distribution pattern using Taylor’s power law and Iwao’s regression model showed that S. avenae exhibited an aggregated distribution on wheat. Taylor’s power law was estimated from 84 data sets and fitted the data better than Iwao’s regression model. The optimal sample sizes needed for fixed precision levels of 0.25 and 0.30 were estimated using Taylor’s regression coefficients, and the required sample sizes increased dramatically with increased levels of precision. Therefore, the samplingplan we presented here should be used as a tool for an efficient estimation of S. avenae population density in wheat fields for pest management decision.
Identification of humic-like substances (HULIS) in oxygenated organic aerosols using NMR and AMS factor analyses and liquid chromatographic techniques
Authors: Paglione M. , Kiendler-Scharr A. , Mensah A. A. , Finessi E. , Giulianelli L. , Sandrini S. , Facchini M. C. , Fuzzi S. , Schlag P. , Piazzalunga A. , Tagliavini E. , Henzing J. S. , Decesari S.
Published: January 2014

Abstract. The atmospheric organic aerosol composition is characterized by a great diversity of functional groups and chemical species, challenging simple classification schemes. Traditional offline chemical methods identify chemical classes based on the retention behaviour on chromatographic columns and absorbing beds. Such an approach led to the isolation of complex mixtures of compounds such as the humic-like substances (HULIS). More recently, online aerosol mass spectrometry (AMS) was employed to identify chemical classes by extracting fragmentation patterns from experimental data series using statistical methods (factor analysis), providing simplified schemes for the classification of oxygenated organic aerosols (OOAs) on the basis of the distribution of oxygen-containing functionalities. The analysis of numerous AMS data sets suggested the occurrence of very oxidized OOAs which were postulated to correspond to HULIS. However, only a few efforts were made to test the correspondence of the AMS classes of OOAs with the traditional classifications from the offline methods. In this paper, we consider a case study representative of polluted continental regional background environments. We examine the AMS factors for OOAs identified by positive matrix factorization (PMF) and compare them to chemical classes of water-soluble organic carbon (WSOC) analysed offline on a set of filters collected in parallel. WSOC fractionation was performed by means of factor analysis applied to proton nuclear magnetic resonance (NMR) spectroscopic data, and by applying an ion-exchange chromatographic method for direct quantification of HULIS. Results show that the very oxidized low-volatility OOAs from AMS correlate with the NMR factor showing HULIS features and also with true "chromatographic" HULIS. On the other hand, UV/VIS-absorbing polyacids (or HULIS {sensu stricto}) isolated on ion-exchange beds were only a fraction of the AMS and NMR organic carbon fractions showing functional groups attributable to highly substituted carboxylic acids, suggesting that unspeciated low-molecular weight organic acids contribute to HULIS in the broad sense.
Contributions of vehicular carbonaceous aerosols to PM2.5 in a roadside environment in Hong Kong
Authors: Hilda Huang X. H. , Bian Q. J. , Louie P. K. K. , Yu J. Z.
Published: January 2014

Abstract. Hourly measurements of elemental carbon (EC) and organic carbon (OC) were made at Mong Kok, a roadside air quality monitoring station in Hong Kong for a year from May 2011 to April 2012. The monthly average EC concentrations were 3.8–4.9 μgC m−3, accounting for 9.2–17.7% of the PM2.5 mass (21.5–49.7 μg m−3). The EC concentrations showed little seasonal variation and peaked twice daily in coincidence with the traffic rush hours of a day. Good correlations were found between EC and NOx concentrations, especially during the rush hours in the morning. In time periods when diesel-powered vehicles dominated the road traffic, the OC / EC ratio was approximately 0.5. The analysis by the minimum OC / EC ratio approach to determine OC / EC ratio representative of primary emissions also yields a value of 0.5, suggesting that it is a reasonable lower limit estimation of (OC / EC)vehicle in representing vehicular emissions. By applying the derived (OC / EC)vehicle ratio to the dataset, the monthly average vehicle-related OC was estimated to account for 16.6–64.0% of the measured OC throughout the year. Vehicle-related OC was also estimated using receptor modeling of a combined dataset of hourly NOx, OC, EC and select volatile organic compounds. The estimations by the two different approaches were in good agreement. When both EC and vehicle-derived organic matter (OM) (assuming an OM-to-OC ratio of 1.4) are considered, vehicular carbonaceous aerosols contributed ~ 7.3 μg m−3 to PM2.5, accounting for ~ 20% of PM2.5 mass (38.3 μg m−3) during winter when Hong Kong was largely influenced by regional transport of air pollutants and ~ 30% of PM2.5 mass (28.2 μg m−3) during summertime when local emission sources were dominant. A reduction of 3.82 μg m−3 in vehicular carbonaceous aerosols was observed during 07:00–11:00 LT (i.e. rush hours on weekdays) on Sundays and public holidays. This could mainly be attributed to less on-road public transportation (e.g. diesel-powered buses) in comparison with non-holidays. These multiple lines of evidence confirm local vehicular emissions as an important source of PM in an urban roadside environment and suggest the importance of vehicular emission control in reducing exposure to PM2.5 in busy roadside environments.
Trace metal distribution in pristine permafrost-affected soils of the Lena River delta and its hinterland, northern Siberia, Russia
Authors: Antcibor I. , Eschenbach A. , Zubrzycki S. , Kutzbach L. , Bolshiyanov D. , Pfeiffer E.-M.
Published: January 2014

Abstract. Soils are an important compartment of ecosystems and have the ability to buffer and immobilize substances of natural and anthropogenic origin to prevent their movement to other environment compartments. Predicted climatic changes together with other anthropogenic influences on Arctic terrestrial environments may affect biogeochemical processes enhancing leaching and migration of trace elements in permafrost-affected soils. This is especially important since Arctic ecosystems are considered to be highly sensitive to climatic changes as well as to chemical contamination. This study characterises background levels of trace metals in permafrost-affected soils of the Lena River delta and its hinterland in northern Siberia (73.5–69.5° N), representing a remote region far from evident anthropogenic trace metal sources. Investigations on the element content of iron (Fe), arsenic (As), manganese (Mn), zinc (Zn), nickel (Ni), copper (Cu), lead (Pb), cadmium (Cd), cobalt (Co), and mercury (Hg) in different soil types developed in different geological parent materials have been carried out. The highest median concentrations of Fe and Mn were observed in soils belonging to ice-rich permafrost sediments formed during the Pleistocene (ice-complex) while the highest median values of Ni, Pb and Zn were found in soils of both the ice-complex and the Holocene estuarine terrace of the Lena River delta region, as well as in the southernmost study unit of the hinterland area. Detailed observations of trace metal distribution on the micro scale showed that organic matter content, soil texture and iron-oxide contents influenced by cryogenic processes, temperature, and hydrological regimes are the most important factors determining the metal abundance in permafrost-affected soils. The observed range of trace element background concentrations was similar to trace metal levels reported for other pristine northern areas.
Nitrogen inputs and losses in response to chronic CO2 exposure in a sub-tropical oak woodland
Authors: Hungate B. A. , Duval B. D. , Dijkstra P. , Johnson D. W. , Ketterer M. E. , Stiling P. , Cheng W. , Millman J. , Hartley A. , Stover D. B.
Published: January 2014

Abstract. Rising atmospheric CO2 concentrations could alter the nitrogen (N) content of ecosystems by changing N inputs and N losses, but responses vary in field experiments, possibly because multiple mechanisms are at play. We measured N fixation and N losses in a subtropical oak woodland exposed to 11 yr of elevated atmospheric CO2 concentrations. We also explored the role of herbivory, carbon limitation, and competition for light and nutrients in shaping response of N fixation to elevated CO2. Elevated CO2 did not significantly alter gaseous N losses, but lower recovery and deeper distribution in the soil of a long-term 15N tracer indicated that elevated CO2 increased leaching losses. Elevated CO2 had no effect on asymbiotic N fixation, and had a transient effect on symbiotic N fixation by the dominant legume. Elevated CO2 tended to reduce soil and plant concentrations of iron, molybdenum, phosphorus, and vanadium, nutrients essential for N fixation. Competition for nutrients and herbivory likely contributed to the declining response N fixation to elevated CO2. These results indicate that positive responses of N fixation to elevated CO2 may be transient, and that chronic exposure to elevated CO2 can increase N leaching. Models that assume increased fixation or reduced N losses with elevated CO2 may overestimate future N accumulation in the biosphere.
Comment on "Comparative study on earthquake and ground based transmitter induced radiation belt electron precipitation at middle latitude", by Sideropoulos et al. (2011)
Authors: Sauvaud J.-A. , Parrot M. , Slominska E.
Published: January 2014

Abstract. We show that many, if not all, electron bursts with energy dispersion claimed to be earthquake precursors by Sideropoulos et al. (2011) are due to the cyclotron resonance of electrons with monochromatic waves from VLF transmitters. The geographic distribution of the VLF-related electron bursts is established during a period in 2007, when the powerful NWC transmitter is off and 20 more transmitters are operating.
Developing fragility functions for the areas affected by the 2009 Samoa earthquake and tsunami
Authors: Gokon H. , Koshimura S. , Imai K. , Matsuoka M. , Namegaya Y. , Nishimura Y.
Published: January 2014

Abstract. Fragility functions in terms of flow depth, flow velocity and hydrodynamic force are developed to evaluate structural vulnerability in the areas affected by the 2009 Samoa earthquake and tsunami. First, numerical simulations of tsunami propagation and inundation are conducted to reproduce the features of tsunami inundation. To validate the results, flow depths measured in field surveys and waveforms measured by Deep-ocean Assessment and Reporting of Tsunamis (DART) gauges are utilized. Next, building damage is investigated by manually detecting changes between pre- and post-tsunami high-resolution satellite images. Finally, the data related to tsunami features and building damage are integrated using GIS, and tsunami fragility functions are developed based on the statistical analyses.
Estimation of flood design hydrographs using bivariate analysis (copula) and distributed hydrological modelling
Authors: Candela A. , Brigandí G. , Aronica G. T.
Published: January 2014

Abstract. In this paper a procedure to derive Flood Design Hydrographs (FDH) using a bivariate representation of rainfall forcing (rainfall duration and intensity) using copulas, which describe and model the correlation between these two variables independently of the marginal laws involved, coupled with a distributed rainfall-runoff model is presented. Rainfall-runoff modelling for estimating the hydrological response at the outlet of a watershed used a conceptual fully distributed procedure based on the soil conservation service – curve number method as excess rainfall model and a distributed unit hydrograph with climatic dependencies for the flow routing. Travel time computation, based on the definition of a distributed unit hydrograph, has been performed, implementing a procedure using flow paths determined from a digital elevation model (DEM) and roughness parameters obtained from distributed geographical information. In order to estimate the return period of the FDH which give the probability of occurrence of a hydrograph flood peaks and flow volumes obtained through R-R modeling has been statistically treated via copulas. The shape of hydrograph has been generated on the basis of a modeled flood events, via cluster analysis. The procedure described above was applied to a case study of Imera catchment in Sicily, Italy. The methodology allows a reliable and estimation of the Design Flood Hydrograph and can be used for all the flood risk applications, i.e. evaluation, management, mitigation, etc.
Crust and upper mantle structures of the Makran subduction zone in south-east Iran by seismic ambient noise tomography
Authors: Abdetedal M. , Shomali Z. H. , Gheitanchi M. R.
Published: January 2014

Abstract. We applied seismic ambient noise surface wave tomography to estimate Rayleigh wave empirical Green's functions from cross-correlations to study crust and uppermost mantle structure beneath the Makran region in south-east Iran. We analysed 12 months of continuous data from January 2009 through January 2010 recorded at broadband seismic stations. We obtained group velocity of the fundamental mode Rayleigh-wave dispersion curves from empirical Green's functions between 10 and 50 s periods by multiple-filter analysis and inverted for Rayleigh wave group velocity maps. The final results demonstrate significant agreement with known geological and tectonic features. Our tomography maps display low-velocity anomaly with south-western north-eastern trend, comparable with volcanic arc settings of the Makran region, which may be attributable to the geometry of Arabian Plate subducting overriding lithosphere of the Lut block. At short periods (<20 s) there is a pattern of low to high velocity anomaly in northern Makran beneath the Sistan Suture Zone. These results are evidence that surface wave tomography based on cross correlations of long time-series of ambient noise yields higher resolution group speed maps in those area with low level of seismicity or those region with few documented large or moderate earthquake, compare to surface wave tomography based on traditional earthquake-based measurements.
Seabed topography beneath Larsen C Ice Shelf from seismic soundings
Authors: Brisbourne A. M. , Smith A. M. , King E. C. , Nicholls K. W. , Holland P. R. , Makinson K.
Published: January 2014

Abstract. Seismic reflection soundings of ice thickness and seabed depth were acquired on the Larsen C Ice Shelf in order to test a sub-ice shelf bathymetry model derived from the inversion of IceBridge gravity data. A series of lines was collected, from the Churchill Peninsula in the north to the Joerg Peninsula in the south, and also towards the ice front. Sites were selected using the bathymetry model derived from the inversion of free-air gravity data to indicate key regions where sub-ice shelf oceanic circulation may be affected by ice draft and seabed depth. The seismic velocity profile in the upper 100 m of firn and ice was derived from shallow refraction surveys at a number of locations. Measured temperatures within the ice column and at the ice base were used to define the velocity profile through the remainder of the ice column. Seismic velocities in the water column were derived from previous in situ measurements. Uncertainties in ice and water cavity thickness are in general < 10 m. Compared with the seismic measurements, the root-mean-square error in the gravimetrically derived bathymetry at the seismic sites is 162 m. The seismic profiles prove the non-existence of several bathymetric features that are indicated in the gravity inversion model, significantly modifying the expected oceanic circulation beneath the ice shelf. Similar features have previously been shown to be highly significant in affecting basal melt rates predicted by ocean models. The discrepancies between the gravity inversion results and the seismic bathymetry are attributed to the assumption of uniform geology inherent in the gravity inversion process and also the sparsity of IceBridge flight lines. Results indicate that care must be taken when using bathymetry models derived by the inversion of free-air gravity anomalies. The bathymetry results presented here will be used to improve existing sub-ice shelf ocean circulation models.
Soil erosion and organic carbon export by wet snow avalanches
Authors: Korup O. , Rixen C.
Published: January 2014

Abstract. Many mountain belts sustain prolonged snow cover for parts of the year, although enquiries into rates of erosion in these landscapes have focused almost exclusively on the snow-free periods. This raises the question of whether annual snow cover contributes significantly to modulating rates of erosion in high-relief terrain. In this context, the sudden release of snow avalanches is a frequent and potentially relevant process, judging from the physical damage to subalpine forest ecosystems, and the amount of debris contained in avalanche deposits. To quantitatively constrain this visual impression and to expand the sparse existing literature, we sampled sediment concentrations of n = 28 river-spanning snow-avalanche deposits (snow bridges) in the eastern Swiss Alps, and infer an orders-of-magnitude variability in specific fine sediment and organic carbon yields (1.8 to 830 t km−2 yr−1, and 0.04 to 131 t C km−2 yr−1, respectively). A Monte Carlo simulation demonstrates that, with a minimum of free parameters, such variability is inherent to the geometric scaling used for computing specific yields. Moreover, the widely applied method of linearly extrapolating plot-scale sample data may be prone to substantial under- or over-estimates. A comparison of our inferred yields with previously published work demonstrates the relevance of wet snow avalanches as prominent agents of soil erosion and transporters of biogeochemical constituents to mountain rivers. Given that a number of snow bridges persisted below the insulating debris cover well into the summer months, snow-avalanche deposits also contribute to regulating in-channel sediment and organic debris storage on seasonal timescales. Finally, our results underline the potential shortcomings of neglecting erosional processes in the winter and spring months in mountainous terrain subjected to prominent snow cover.
Quantitative evaluation of blood glucose concentration using impedance sensing devices
Authors: Pradhan Rangadhar , Mitra Analava , Das Soumen
Published: January 2014

This paper reports on the impedimetric investigation of glucose concentrations present in the human blood by using impedance sensing devices with different working electrode areas. It is evident from the experiment that, the impedance value increases with the increase of glucose concentration in blood and the trend follows in all the devices with various electrode areas. The measured complex admittance plot shows two semicircles which are due to double layer and coating capacitances respectively. Lower values of relative standard deviation in impedance data infer the reproducibility of these devices. A quantitative relationship, developed between the impedance and glucose concentration establishes a positive correlation between the blood glucose values and impedance.
Atributos químicos e matéria orgânica em complexos florestais periodicamente inundados na restinga da Marambaia - RJ
Authors: Paula Ranieri Ribeiro , Pereira Marcos Gervasio , Machado Deivid Lopes
Published: January 2014

http://dx.doi.org/10.5902/1980509812337Esse trabalho teve como objetivo avaliar as propriedades químicas e caracterizar a matéria orgânica de solos sob duas formações florestais periodicamente inundadas, na ilha da Marambaia, RJ. Essas formações apresentam diferenças quanto ao grau de saturação hídrica do solo, causada pela influência do lençol freático, sendo que na formação 1 (F1) o lençol apresenta-se mais próximo à superfície em comparação à formação 2 (F2). Amostras foram coletadas nas camadas 0,00-0,05, 0,05-0,10 e 0,10-0,20 m. As propriedades edáficas avaliadas foram: pH, H++Al+3; Ca+2, Mg+2, Na+, K+, P, N, carbono orgânico total (COT) e saturação por bases (V%); carbono da fração humina (C-HUM), carbono da fração ácido húmico (C-FAH) e carbono da fração ácido fúlvico (C-FAF). Valores estatisticamente superiores de pH foram observados para F1. Em F2 verificaram-se maiores valores de Mg+2, P, N e V%. Foi verificada correlação entre os teores de Mg+2, N, ácido húmico e ácido fúlvico em F1 com o lençol freático, e do lençol em F2 com os elementos Na+ e K+. A fração C-HUM foi a mais representativa do carbono orgânico total, seguida por C-FAH e C-FAF. Os teores de COT foram maiores na formação F1. A relação C/N foi menor em F2, com valores variando entre 9 e 12, e em F1 foram verificados maiores valores dessa relação, variando de 9 a 15. Dentre as vias de formação dos solos de constituição orgânicas, em ambas as áreas a principal via de acumulação da matéria orgânica é a de herança.
Ocorrência e patogenicidade de Meloidogyne javanica sobre plantas de teca (Tectona grandis Linn. F.)
Authors: Oliveira Anmyna Soraia de , Silva Rosangela Aparecida da
Published: January 2014

http://dx.doi.org/10.5902/1980509812340A teca (Tectona grandis) é originária da Ásia e foi introduzida no estado de Mato Grosso na década de 70. Em uma análise de raízes da planta de teca, coletada no município de Nova Maringá, MT, foi revelada a presença do nematoide Meloidogyne javanica, a qual foi confirmada pelas características morfológicas da estrutura perineal da fêmea. Massas de ovos foram extraídas de raízes de teca e transferidas para plantas de tomateiro para manutenção da população. Como não havia informações disponíveis sobre esse patossistema, dois trabalhos foram instalados com o objetivo de avaliar a patogenicidade de Meloidogyne javanica sobre plantas de teca. Constatou-se que a teca comportou-se como hospedeira suscetível do nematoide, pois o fator de reprodução (Pf = população final do nematoide/população inicial) variou de 2,6 a 27. Além disso, agressivo, pois as plantas exibiram severo sintoma de deficiência nutricional. No entanto, em condições controladas, não houve diferença significativa em relação ao nível populacional do nematoide e o desenvolvimento das plantas.
Caracterização fitossociológica e fitogeográfica de um trecho de floresta ciliar em Alfredo Wagner, SC, como subsídio para restauração ecológica
Authors: Silva Ana Carolina da , Higuchi Pedro , Negrini Marcelo , Grudtner Andriele , Zech Diego Fernando
Published: January 2014

http://dx.doi.org/10.5902/1980509812342Os conhecimentos florístico e estrutural da comunidade arbórea são fundamentais para subsidiar estratégias de restauração florestal. Neste sentido, foi realizado um levantamento fitossociológico em um fragmento florestal situado nas margens de um tributário do Rio Caeté em Alfredo Wagner, SC, objetivando: i) conhecer a estrutura e a florística da vegetação arbórea dessa floresta; ii) classificar as espécies encontradas em grupos ecológicos e iii) comparar a florística da área estudada com outros estudos realizados em Floresta Ombrófila Mista (FOM), Floresta Ombrófila Densa (FOD) e área de transição entre FOM-FOD de Santa Catarina. Nesse fragmento foram alocadas 10 parcelas de 400 m2 onde todos os indivíduos arbóreos que apresentaram Circunferência a Altura do Peito (CAP, medido a 1,30 m do solo) igual ou superior a 15,7 cm foram medidos, marcados e identificados. As espécies foram classificadas nos grupos sucessionais: pioneira, clímax exigente de luz ou clímax tolerante à sombra. Para a comparação florística com outros remanescentes, foi utilizada a Análise de Correspondência Retificada (DCA). A estrutura do componente arbóreo foi descrita pela densidade, frequência, dominância e Valor de Importância (VI). Os resultados demonstram elevada riqueza florística (98 espécies). Foi possível constatar espécies típicas de FOM, como Araucaria angustifolia (Bert.) Kuntze, e espécies características de FOD, como Byrsonima ligustrifolia A.Juss., confirmando a característica do fragmento estudado de pertencer a uma área de tensão ecológica, padrão confirmado na comparação da similaridade florística. As espécies com maior VI foram Psychotria vellosiana Benth., Alsophila setosa Kaulf. e Guatteria australis A.St.-Hil. Estas e outras espécies de alto VI, por suas consideráveis representatividades na área, são importantes na restauração de florestas ciliares degradadas na região. Os plantios deverão ser planejados obedecendo-se ao grupo sucessional das espécies, plantando-se as espécies pioneiras e clímax exigentes de luz em um primeiro momento (e.g. Psychotria vellosiana), seguidas, quando houver o sombreamento da área, das espécies clímax tolerantes à sombra (e.g. Alsophila setosa e Guatteria australis).
Embriogênese somática e morfoanatomia de embriões somáticos de Ocotea porosa
Authors: Pelegrini Luciana Luiza , Ribas Luciana Lopes Fortes , Amano Erika , Quoirin Marguerite
Published: January 2014

http://dx.doi.org/10.5902/1980509812343Ocotea porosa apresenta sementes com forte dormência tegumentar, comportamento recalcitrante, baixa germinação e irregularidade, o que dificulta a propagação natural. O objetivo deste trabalho foi estabelecer um protocolo de embriogênese somática para Ocotea porosa. Eixos embrionários zigóticos imaturos foram inoculados em meio de cultura WPM suplementado com 2,4-D (200 μM) combinado ou não com caseína hidrolisada ou glutamina (0,5 ou 1 g l-1) durante 90 dias. A embriogênese repetitiva foi induzida em meio contendo 2,4-D (22,62 μM) combinado com 2-iP (2,46 μM) seguido de transferência para meio de cultura com caseína hidrolisada ou glutamina (1 g l-1), durante 90 dias cada. A maturação dos embriões somáticos foi testada em meio de cultura contendo ANA (0,5 μM) e 2-iP (5, 10 ou 20 μM). A maior porcentagem de embriões somáticos induzidos (8,3%) foi observada em meio de cultura WPM contendo 200 μM de 2,4-D e 1 g l-1 de caseína hidrolisada e o desenvolvimento de embriões somáticos ocorreram de forma indireta. A embriogênese somática repetitiva foi promovida em meio de cultura WPM contendo caseína hidrolisada ou glutamina, no entanto, a caseína hidrolisada promoveu a manutenção da competência embriogênica por mais de dois anos. Na fase de maturação, houve baixa progressão dos embriões globulares para os estádios cordiforme e torpedo. Os diferentes estádios ontogenéticos de embriões somáticos de Ocotea porosa foram caracterizados pelo estudo histológico.
Teor e alocação de nutrientes em plantio de Platanus x acerifolia (Aiton) Willd. em Dom Feliciano – RS
Authors: Witschoreck Rudi , Schumacher Mauro Valdir
Published: January 2014

http://dx.doi.org/10.5902/1980509812350Este trabalho teve por objetivo avaliar o teor e o padrão de alocação dos nutrientes nos diferentes componentes da biomassa de Platanus x acerifolia, em um povoamento com 5,5 anos de idade, localizado no município de Dom Feliciano-RS. Foram amostradas 24 árvores, com base na amplitude diamétrica, com determinação da biomassa, concentração e estoque de nutrientes nos seguintes componentes: folhas, frutos, galhos, casca do tronco, madeira do tronco e raízes. Para estudar a variação no teor dos nutrientes foram coletadas amostras de casca e madeira em diferentes posições ao longo do tronco. A estimativa do estoque de nutrientes, em cada componente, baseou-se nos valores médios, da biomassa e do teor de nutrientes, pelo número de árvores por classe diamétrica por hectare. A variação da concentração dos nutrientes ao longo do tronco, na casca e na madeira, foi estudada a partir do ajuste de equações de regressão, correlacionando concentração de nutrientes e a altura de coleta das amostras. Em termos médios, considerando-se todos os componentes da biomassa, prevaleceu a seguinte sequência quanto à concentração nutricional: N > Ca > K > Mg > P > S > Fe > Mn > B > Zn > Cu. Os maiores teores, para a maioria dos nutrientes, foram observados nas folhas e os menores, para todos os nutrientes, foram verificados na madeira do tronco. O estoque total de nutrientes na biomassa de Platanus x acerifolia foi de 574,72 kg ha-1, de acordo com a seguinte ordem de alocação, entre os componentes: madeira do tronco ~ galhos > raízes ~ folhas > casca do tronco > frutos. Quanto aos nutrientes, a sequência de acúmulo foi a seguinte: N > K > Ca > Mg > S > P > Fe > Mn > B > Zn > Cu, sendo que N, K e Ca, representam 82,9% do total. Foi verificada grande variação na concentração de nutrientes ao longo do tronco, na casca e na madeira, com distinção dos padrões básicos: crescente, decrescente e invariável, da base da árvore em direção do ápice.
Relação entre alongamento anual da copa e o incremento diamétrico de árvores singulares de Cedrela fissilis (Vell)
Authors: Cunha Thiago Augusto da , Cavalli Jean Pierre , Finger César Augusto Guimarães
Published: January 2014

http://dx.doi.org/10.5902/1980509812354O crescimento da copa é uma variável pouco conhecida no campo florestal. Esta estrutura fotossintética tão importante para o crescimento da árvore encontra-se em um nível de difícil acesso para o manejador florestal e, portanto, pouco se conhece sobre seu desenvolvimento. Assim, o objetivo dessa pesquisa foi modelar o alongamento anual da copa utilizando como variável independente o incremento corrente anual em diâmetro do tronco de Cedrela fissilis. Utilizando 22 árvores singulares determinou-se o alongamento anual da copa e o incremento corrente anual em diâmetro no período de oito anos. Demonstrou-se que o desenvolvimento da copa esta relacionado com o incremento diamétrico (r=0,53; p<0,0001), entretanto, para estimar o alongamento anual da copa com maior precisão, o modelo linear misto também incluiu o diâmetro a altura do peito e a altura comercial, que explicou 70% da variação total do alongamento do galho por classe de altura total.
Dinâmica da flora arbustivo-arbórea colonizadora em uma área degradada pela extração de ouro em Diamantina, MG
Authors: Amaral Wander Gladson , Pereira Israel Marinho , Amaral Cristiany Silva , Machado Evandro Luiz Mendonça , Rabelo Luiz David Oliveira
Published: January 2014

http://dx.doi.org/10.5902/1980509812355O objetivo deste trabalho foi conhecer o processo de dinâmica da vegetação colonizadora em uma área degradada pela extração de ouro. A área em estudo foi estratificada em três ambientes, sendo que em cada ambiente foram alocadas dez parcelas contiguas de 100 m² cada. Para a abordagem da dinâmica foram realizados dois inventários da vegetação arbustivo-arbórea incluindo todos os indivíduos com DAS30 > 3 cm. O primeiro inventário foi realizado no ano de 2008 e o segundo no ano de 2010. Em 2010, os novos indivíduos que atingiram o critério de inclusão (recrutas) foram marcados e medidos, os mortos foram registrados e os sobreviventes mensurados novamente. Foram calculadas as taxas de dinâmica: mortalidade, recrutamento, ganho e perda em área basal de cada ambiente, ficando evidente a importância da dinâmica como ferramenta para auxiliar no entendimento das relações de sucessão ecológicas das espécies. Os índices de diversidade de Shannon entre os três ambientes foram comparados pelo teste t de Hutcheson e foi utilizada a análise de espécies indicadoras na determinação das espécies preferências de cada um dos três ambientes pré-determinados. O número total de indivíduos passou de 707 para 909 em dois anos de intervalo, reforçando ainda mais a importância de regeneração natural nos processos de sucessão ecológica. O ambiente II manteve-se como o mais abundante, apesar de apresentar elevada taxa de mortalidade, o que pode ser explicado pela alta taxa de recrutamento. As espécies Eremanthus incanus, Trembleya laniflora, Trembleya parviflora, Roupala montana, Coccoloba brasiliensis e Tibouchina candoleana, apresentaram maior valor de importância nos dois levantamentos realizados, mostrando, assim, superioridade na colonização da área degradada pela extração de ouro, podendo vir a ser indicadas em programas de recuperação de áreas degradadas que se encontram em condições semelhantes na região de Diamantina.
Influência da exploração florestal de impacto reduzido sobre as fases de desenvolvimento de uma floresta de terra firme, Pará, Brasil
Authors: Francez Luciana Maria de Barros , Carvalho João Olegário Pereira de , Batista Fábio de Jesus , Jardim Fernando Cristóvam da Silva , Ramos Edson Marcos Leal Soares
Published: January 2014

http://dx.doi.org/10.5902/1980509812358Avaliou-se a influência da exploração florestal de impacto reduzido nas fases de desenvolvimento de uma floresta de terra firme, submetida a duas intensidades de colheita de madeira na região de Paragominas, PA. Os dados foram coletados em 36 parcelas permanentes de 0,25 ha, distribuídas aleatoriamente entre os tratamentos (T1 - floresta explorada com colheita apenas do fuste comercial das árvores e T2 - floresta explorada com colheita do fuste e dos resíduos lenhosos) e testemunha (T0 - floresta não explorada). Foram consideradas três fases de desenvolvimento da floresta: madura (DAP > 40 cm); em construção (10 cm < DAP < 40 cm); e clareiras (ocorrência de uma abertura no dossel e pouca ou nenhuma árvore com DAP > 10 cm). Para verificar a homogeneidade de variâncias das subparcelas entre tratamentos, fases e anos, recorreu-se ao teste de Bonferroni, a partir das estatísticas de Bartlett e Levene. Foi aplicada uma análise de variância para o número de subparcelas por fases, anos e tratamentos, ao nível de significância de 5%. Foi realizado, também, o teste Tukey para contrastar as médias da interação entre as fases e ano. Antes da exploração, a floresta encontrava-se com 57,0% da área em estádio de construção, 38,9% em estádio de floresta madura e apenas 4,1% em fase de clareira. A exploração reduziu a área de floresta madura e em construção, ocasionando o aumento do número de clareiras, entretanto, esse aumento não apresentou diferença estatística. Um ano após a exploração foi observado o aumento da área de floresta madura (38,4%) e de construção (53,1%) e a redução das áreas de clareiras (8,4%). Três anos após a exploração os percentuais observados (Floresta madura: 37,1%; Floresta em construção: 57,9%; Clareira: 5,0%), foram semelhantes aos encontrados antes da exploração florestal. As fases de desenvolvimento da floresta não foram influenciadas pela exploração florestal, ao longo do período estudado, independente do tratamento empregado. A floresta em estudo demonstrou capacidade de se regenerar, proporcionando o fechamento do dossel, apesar do curto espaço de tempo.
Propriedades físicas e mecânicas de painéis de madeira aglomerada de Acrocarpus fraxinifolius, compostos com diferentes percentuais de casca
Authors: Trianoski Rosilani , Iwakiri Setsuo , Matos Jorge Luis Monteiro de , Prata José Guilherme
Published: January 2014

http://dx.doi.org/10.5902/1980509812360A indústria de painéis de madeira aglomerada tem utilizado grandes volumes de madeira, sobretudo de florestas plantadas de Pinus, sendo necessário diversificar espécies, bem como maximizar o uso da matéria-prima. Uma das maneiras de maximizar o uso deste recurso é a utilização da casca no processo produtivo. Desta forma, este trabalho teve como objetivo avaliar as propriedades físicas e mecânicas de painéis aglomerados de Acrocarpus fraxinifolius contendo diferentes percentuais de casca. Foram manufaturados painéis com 100% de partículas de madeira de Acrocarpus fraxinifolius e painéis com partículas da madeira de Acrocarpus e percentuais de casca de 10%, 20% e 30%, massa especifica nominal de 0,75 g/cm3 e 8% de resina. As propriedades de massa especifica aparente, absorção de água e inchamento em espessura, flexão estática, tração perpendicular à superfície e arrancamento de parafuso foram determinadas de acordo com as normas EN e NBR, e comparadas com um tratamento testemunha (100% Pinus taeda) e com requisitos normativos prescritos pelas respectivas normas. Os resultados demonstraram que a espécie apresenta viabilidade técnica para produção de painéis de madeira aglomerada e que a crescente adição de casca não afetou negativamente as propriedades físicas e mecânicas dos painéis.
Técnicas multivariadas aplicadas à avaliação de resíduos lignocelulósicos para a produção de bioenergia
Authors: Protásio Thiago de Paula , Bufalino Lina , Guimarães Junior Mario , Tonoli Gustavo Henrique Denzin , Trugilho Paulo Fernando
Published: January 2014

http://dx.doi.org/10.5902/1980509812361Na avaliação de resíduos lignocelulósicos para a produção de bioenergia é necessário considerar as várias características e propriedades que podem ser correlacionadas. Este fato demanda o emprego de diversas técnicas de análise multivariada que possibilitem a avaliação dos fatores energéticos mais relevantes. O objetivo deste trabalho foi aplicar as análises de agrupamento e componentes principais na seleção e avaliação de resíduos lignocelulósicos visando à produção de bioenergia. Foram utilizados 8 tipos de biomassa residual, dos quais foram determinados os teores dos componentes elementares (C, H, O, N, S), os teores de lignina, extrativos totais e cinzas, a densidade básica e o poder calorífico superior e inferior. As duas técnicas multivariadas empregadas para a avaliação e seleção de resíduos lignocelulósicos para a produção de energia foram eficientes, sendo observadas similaridades entre os grupos de biomassa formados por elas. Pela interpretação da primeira componente principal obtida, criou-se um índice de desempenho global para avaliar a viabilidade do aproveitamento energético da biomassa. A interpretação da segunda componente principal permitiu um contraste entre os teores de nitrogênio e enxofre e o teor de oxigênio.
Comparison of Executive Functions in School Children Aged 7 to 12 Years in a State of Malnutrition Due to Thinness, Risk of Thinness and a Control Group of an Educational Institution of the Locality of Ciudad Bolívar- Bogotá, D.C.
Authors: Rivera-Oliveros D.M. , Rico-Navarro L.M. , Acosta-Barreto M.R.
Published: January 2014

The aim of this research was to compare the neuropsychological performance of executive functions of school children in a state of malnutrition caused by thinness and risk of thinness and a control group of a District educational institution of the locality of Ciudad Bolívar in Bogotá, Colombia. The research used a descriptive cross-sectional comparative design, where children aged between 7 and 12 years were selected based on the diagnosis of malnutrition. The executive functions assessed were fluency, working memory, problem solving, inhibitory control and cognitive flexibility, through the Neuropsychological Battery for Children [ENI, for its Spanish acronym] and the original version of Stroop and Wisconsin tests. Results showed statistically significant differences in executive functioning between the children with thinness, thinness risk and the control group. The students with thinness showed a low performance in verbal fluency, visual fluency, working memory, cognitive flexibility and inhibitory control compared with students in a state of malnutrition due to thinness risk and those with normal weight (control group). In conclusion, a strong association was found between the effect of child malnutrition and poor performance in executive tasks where there is evidence that executive functioning is more affected in children with malnutrition due to thinness (severe malnutrition) than in children with malnutrition due to thinness risk and in those of the control group.
Dysgraphia in Relation to Cognitive Performance in Patients with Alzheimer’s Disease
Authors: Onofri Emanuela , Mercuri Marco , Salesi MariaLucia , Ferrara Salvatore , Troili Giulia Maria , Simeone Claudio , Ricciardi Max Rapp , Ricci Serafino , Archer Trevor
Published: January 2014

Dysgraphia has been observed in patients presenting mild to moderate levels of Alzheimer’s disease (AD) in several studies. In the present study, 30 AD patients and 30 matched healthy controls, originating from the Lazio region, Rome, Italy, were examined on tests of letter-writing ability and cognitive performance over a series of 10 test days that extended over 19 days (Test days: 1, 3, 5, 7, 9 11, 13, 15, 17, and 19). Consistent deficits by the AD patients over the initial cognition test (PQ1), 2nd cognition test (PQ2) and the difference between them (D∆), expressing deterioration, and writing-time compared the group of healthy control subjects were obtained. Furthermore, the performances of the AD patients on the PQ1, D∆ and writing-time, but not the PQ2, tests deteriorated from the 1st five days of testing (Days 1-9) to the 2nd five days (11-19). Both AD patients’ and healthy controls’ MMSE scores were markedly and significantly correlated with performance of PQ1, writing-time and PQ2. The extent of dysgraphia and progressive deficits in the AD patients implicate multiple brain regions in the loss of functional integrity.