13 research outputs found
Relazione tra cross-bite monolaterale e postura
No full textOcclusion disorders have been often thought as a determining factor or a pre-existing cause of many musculoskeletal diseases due to the observation that masticatory muscles belong to the so called "postural chain". The Authors noticed that many studies looked for a sagittal correlation with problems affecting the transverse diameters while sometimes incorrect mandibular positions occurred with skeletal disorders. In the present research, the Authors chose children with monolateral crossbite, without any other occlusion disharmony, skeletal disorder or vision pathology to look for differences in foot support between the right and the left side of the body by using a stabilonzetric board. The results show that children with monolateral crossbite have monolateral support too, and this happens on the side of normal occlusion. In contrast with musculoskeletal disorders where a postural compensation may occur thanks to the "postural chain' it seems that a skeletal asymmetry produces a loss of balance in the whole body
Eukoenenia gallii
No full textEukoenenia gallii, species nova Material examined. Holotype female: Italy, Liguria, Savona Province, Bergeggi (44 ° 15 ′ 27 ″N, 8 ° 26 ′ 35 ″E); 5 July 2007, leg. M. Capurro, D. Duradoni & L. Galli. Seven paratypes: 1 male (6 March 2007), 3 females (5 July 2007), 1 female (13 June 2007), 1 juvenile male (30 July 2007) and 1 juvenile female (30 July 2007). One larva (5 July 2007) is not included in the type series. All specimens with same locality and collectors as the holotype. Deposition. Museum of Natural History, Vienna, Austria, Arachnological Collection. Acquisition numbers 21.700 (holotype), 21.701–21.707 (paratypes). Etymology. I dedicate the new species to Dr Loris Galli (Università degli Studi di Genova), who provided the specimens and ecological information. Diagnosis. Adult specimens small (body length esd> grt; stiff seta r as long as segment, inserted clearly below middle of segment. Unlike the completely pubescent legs I–III, leg IV shows glabrous areas on the ventral surface of the proximal joints, including the tibia. Opisthosoma: The chaetotaxy of the opisthosoma is given in Tab. 2. Tergite II with t, t 1, t 3 and s, tergites III–VI additionally with t 2. The unpaired median seta t is inserted caudal to the line t 1 –t 1. Tergal setae s are more slender and lack a typical basal ring (Fig. 12). Sternite VI with a 1, a 2, s 1 and s 2, sternites IV and V additionally with a 3 (Fig. 13). Sternal setae s 1 and s 2 with normal basal ring and a slender and evenly tapering shaft. Setae of the a-groups considerably thicker and subcylindrical, setae a 1 slightly longer than the distance between them (19:18, 20: 16 and 21: 18 μm on the sternites IV–VI of holotype). Pair of sternal pores situated caudal to line a 1 –a 1, most markedly so on sternite VI. Segments VII–XI with rich chaetotaxy and showing some variation in the number of setae, but segment XI with 10 setae throughout: 17 –18, 15–16, 12–14, 12 (10 in one female), and 10. The longest setae of XI are shorter than the segment length (about 50: 70). The pubescence of segments IX–XI is largely reduced: the surface is glabrous except for a small posteroventral area on segment IX and a circular single-row fringe of somewhat longer (max. 6 μm) hair-like structures. The fringe runs along the connecting line of the setal bases on IX and X, and caudal to this line on XI (Figs. 14, 15). The flagellum is connected to segment XI via an intermediate ring with 2 short dorsal and 2 longer and thicker ventral setae (Figs. 14, 15); the part of the flagellum distal of the intermediate ring (present only in the holotype) is composed of 14 articles (Fig. 16), short (506 μm = 52 % of body length), and evenly tapering from the wide basal articles; article 2 wider than long; articles 1–14 bear 10, 10, 9, 8, 8, 8, 8, 8, 8, 8, 7, 7, 7, 6 (+ 1 short apical) setae; the spikes of the apical crown (Fig. 17) are long on articles 1, 2, 3, 5, 7, 9, and short on the others. Female genital area (Fig. 18): First lobe shaped as an obtuse-angled triangle without apical indentation; with uniform pubescence and 11 + 11 setae: 2 + 2 sternal setae (st 1, st 2) followed, on the lobe proper, by 3 +3, 1+1, 1+ 1 and 4 + 4; of the 4 apical setae, a 3 is somewhat longer (12 μm) than the others. Two halves of second lobe with 3 setae each. A nearly linear group of 3 gland orifices (2 μm in diameter) lies on either side on the interior surface of the first lobe, an L-shaped group of 4 orifices on either half of the second lobe. The optical section of the spermatheca is roundish, 13–16 μm in diameter. FIGURES 12–17. Eukoenenia gallii, opisthosoma. 12, chaetotaxy and pubescence of tergite V (plane of symmetry indicated by black line); t–s = 100 μm. 13, chaetotaxy and pubescence of sternite IV (plane of symmetry indicated by black line); a 1 –s 2 = 88 μm. 14, lateral view of segments IX–XI and intermediate ring of the flagellum (juvenile female), showing fringes of hair-like cuticular structures and lack of pubescence (except a ventral area on sternite IX). 15, dorsal view of segment XI and the intermediate ring, showing fringes and lack of pubescence. 16, tip of opisthosoma and flagellum (holotype); length of flagellum 506 μm. 17, articles 1–5 of flagellum (same specimen). Male genital area (Figs. 19– 22): Two halves of first lobe not gaping, the lobe appears as a single element, wider than long; common distal margin of the two uniformly pubescent halves is straight, not extended into a pair of flaps, with a faint medial indentation; with 11 + 11 setae (one asymmetrically missing in the paratype): 2 + 2 sternal setae (st 1, st 2) followed, on the lobe proper, by 4 + 3 (1 missing), 2 + 2, and 3 + 3; the latter are inserted on the distal margin, along with 2 + 2 fusules (f 1 = 21 μm, f 2 = 26 μm). Two flaps of second lobe each with a pointed tip and 4 setae (a, b, c, d). Two flaps of the third lobe bifurcate with pointed tips and 4 setae each (w, x, y, z). Description of immature stages. Morphometric data are given in Table 1. Juvenile female and juvenile male (larves B and C sensu Condé 1996): Lateral organ with two blades. Labrum with 4 + 4 setae. Deuto-tritosternum with 3 setae. Fingers of chelicera with 7 teeth. Chaetotaxy of propeltidium and metapeltidium complete. Coxae II–IV with 3, 3, and 1 thickened setae. Trichobothria as in adult. No forked seta on bta 1. IV bta with complete setation. Tergites II–VI with 2 + 2 setae (t and t 3 missing) between the setae s. Sternites IV–VI as in adult, except for absence of setae s 2; gland orifices present. Segments VII–XI with 11, 12, 9, 9 and 8 setae. Primordia of genital lobes developed on segments II and III. Segment II shows 1 + 1 (st 1), segment III 2 + 2 sternal setae (st 2, st 3) in both sexes. Indented anterior lobe of the juvenile female (Fig. 23) with 3 + 3 long and 2 + 2 minute subapical setae; posterior lobe with 1 + 1 long setae. Juvenile male (Fig. 24) bears two rows of 2 + 2 and 3 + 3 long setae on deeply indented anterior lobe; 2 + 1 minute setae (1 missing asymmetrically), similar to those of the juvenile female, on a structure that might develop into the middle lobe; and 1 + 1 long setae on posterior lobe. Larva (larve A sensu Condé 1996), sex indeterminable: Lateral organ with one blade. Labrum with 3 + 3 setae. Deuto-tritosternum with 1 seta. Fingers of chelicera with 7 teeth. Chaetotaxy of propeltidium and metapeltidium complete. Coxae II–IV with 3, 3, and 0 thickened setae. Five trichobothria, those of bta 1 missing. No forked seta on bta 1. IV bta with 2 setae (grt and 1 esd missing). Tergites II–VI with 2 + 2 setae (t and t 3 missing) between the setae s. On sternites IV–VI, only setae a 1 and a 2 are developed, setae s missing; no paramedian gland orifices discerned. Segments VII–XI with 6, 8, 8, 8, and 8 setae. Genital region (Fig. 25) shows no primordia of lobes; segment II bears 2 + 2 sternal setae (st 1, st 2), segment III 3 + 3 (st 1, st 2, st 3). One pair of segment II setae might shift to the first lobe in the subsequent stage. Similarly, st 1 of segment III might develop into the single pair and finally into the external pair of setae on the caudal genital lobe of the successive stages. TABLE 1. Morphometric data of the eight type specimens and one larva of Eukoenenia gallii. Measurements are presented in micrometers (whole numbers), indices are given as decimals. L = body length, B = length of propeltidium, P = pedipalp, I = leg I, IV = leg IV, ti = tibia, bta = basitarsus, ta = tarsus, a = width of IV bta at the insertion of seta r, er = distance between the basis of IV bta and the insertion of seta r. Setae typeset in italics. m = male, f = female, juv. = juvenile, * = holotype. Character m f 1 * f 2 f 3 f 4 f 5 m juv. f juv. larva L 970 980 890 950 950 960 840 800 690 B 221 218 218 225 220 218 167 168 160 P ti 70 70 71 71 74 70 57 54 43 P bta 1 26 27 23 26 25 21 21 18 18 P bta 2 28 26 24 26 26 26 21 20 17 P ta 1 16 15 14 13 14 15 13 12 10 P ta 2 21 20 20 19 18 21 20 17 16 P ta 3 36 35 34 37 38 36 31 29 28 I ti 69 67 70 68 67 70 55 51 40 I bta 1 + 2 57 57 55 59 57 57 47 44 36 I bta 3 27 27 28 27 26 25 24 22 18 I bta 4 30 26 29 30 27 26 27 24 20 I ta 1 15 15 15 15 14 15 14 12 12 I ta 2 21 21 22 22 20 20 19 17 17 I ta 3 67 66 63 66 65 67 57 56 52 I bta 3 grt 35 32 30 35 34 31 28 27 23 I bta 3 r 35 35 32 36 37 34 30 29 25 IV ti 72 71 71 71 70 70 56 55 48 IV bta 47 45 46 47 45 47 40 37 32 IV ta 1 32 30 29 28 32 31 26 25 22 IV ta 2 34 41 33 36 37 33 33 32 31 a 17 17 16 20 19 16 17 17 16 er 16 15 16 15 16 17 15 15 12 IV bta grt 27 26 22 23 25 26 23 22 -- IV bta esd 34 33 31 33 35 33 29 30 23 IV bta r 44 45 42 43 44 42 35 35 31 IV bta / r 1.07 1.00 1.10 1.09 1.02 1.12 1.14 1.06 1.03 IV bta / er 2.94 3.00 2.88 3.13 2.81 2.76 2.67 2.47 2.67 IV bta / ti 0.65 0.63 0.65 0.66 0.64 0.67 0.71 0.67 0.67 B / IV bta 4.70 4.84 4.74 4.79 4.89 4.64 4.18 4.54 5.00 TABLE 2. Eukoenenia gallii n. sp. Opisthosomal chaetotaxy of adult (5 f, 1 m) and immature (1 f juv., 1 m juv., 1 larva) specimens. * = missing in juvenile female and male; framed: missing in the larva. Adult Immature Tergite Sternite Tergite Sternite II t t 1 t 3 s st 1 st 2 t 1 t 2 s st 1 st 2 * III t t 1 t 2 t 3 s st 2 st 3 t 1 t 2 s st 1 * st 2 st 3 IV t t 1 t 2 t 3 s a 1 a2 a 3 s 1 s 2 t 1 t 2 s a 1 a2 a 3 s 1 V t t 1 t 2 t 3 s a 1 a2 a 3 s 1 s 2 t 1 t 2 s a 1 a2 a 3 s 1 VI t t 1 t 2 t 3 s a 1 a2 s 1 s 2 t 1 t 2 s a 1 a2 s 1 VII 17 (4 f, 1 m), 18 (1 f) juv 11 larv 6 VIII 15 (2 f), 16 (3 f, 1 m) juv 12 larv 8 IX 12 (3 f), 13 (1 f, 1 m), 14 (1 f) juv 9 larv 8 X 10 (1 f), 12 (4 f, 1 m) juv 9 larv 8 XI 10 (5 f, 1 m) juv 8 larv 8Published as part of Christian, Erhard, 2009, A new soil-dwelling palpigrade species from Northern Italy (Palpigradi: Eukoeneniidae), pp. 59-68 in Zootaxa 2136 on pages 60-65, DOI: 10.5281/zenodo.27497
A Phase Equilibrium Diagram for the Vanadium-Gallium System (Diagramma Ravnovesiya Faz Sistemy Vandii-Gallii)
No full textPhytogeographical relations in the North West European heath
No full textThe water economy, the mineral content of the soil, and human influence are the principal ecological factors governing the variation of the heath vegetation of a limited region. Sloping of the surface is also an important factor. In hilly country it is of a twofold nature: on the one hand the difference between high and low altitudes, based on the water economy, on the other hand differences in (micro-) climate. If the hills are higher, this results in greater climatic differences. In extremely oceanic and in boreal regions a rise in altitude of 100 m is sufficient for creating a noticeable decrease in temperature and an increase in precipitation, aerial moisture, and wind force.
This results in the occurrence on the hills of heath communities that have their main distribution more to the North. The same observation was made by Gimingham (1961). On Slieve League on the Donegal coast (Ireland) Salix herbacea and Lycopodium selago occur in the heath at an altitude of 600 m, near Tongue on the Scottish north coast Dryas octopetala, Saxifraga oppositifolia, Alchemilla alpina and Thalictrum alpinum at an altitude of 60 m. West of Apeldoorn in the Netherlands are found extensive stretches of heath with abundant Vaccinium myrtillus and V. vitis-idaea at an elevation of 60-80 m, even on south-facing slopes. This is an area with high precipitation due to ascending air west of the hill ridge of the Eastern-Veluwe. Here the Vacciniums, elsewhere requiring the protection of the forest, can tolerate the habitat of the open heath (Stoutjesdijk, 1959; De Smidt, 1966). Higher elevation combined with north-facing slopes creates extreme conditions e.g. on Roc Trévézel (300—360 m) in Brittany, with Vaccinium myrtillus, Melampyrum pratense, Hymenophyllum wilsonii and Rhytidiadelphus loreus. These species are virtually lacking in the surrounding plains where the heath consists of such South Atlantic species as Erica cinerea, E. ciliaris, Ulex gallii, Lobelia urens, Lithospermum prostratum and Symethis planifolia
The Hidden Diversity of Zanclea Associated with Scleractinians Revealed by Molecular Data.
No full textScleractinian reef corals have recently been acknowledged as the most numerous host group found in association with hydroids belonging to the Zanclea genus. However, knowledge of the molecular phylogenetic relationships among Zanclea species associated with scleractinians is just beginning. This study, using the nuclear 28S rDNA region and the fast-evolving mitochondrial 16S rRNA and COI genes, provides the most comprehensive phylogenetic reconstruction of the genus Zanclea with a particular focus on the genetic diversity among Zanclea specimens associated with 13 scleractinian genera. The monophyly of Zanclea associated with scleractinians was strongly supported in all nuclear and mitochondrial phylogenetic reconstructions. Furthermore, a combined mitochondrial 16S and COI phylogenetic tree revealed a multitude of hidden molecular lineages within this group (Clades I, II, III, V, VI, VII, and VIII), suggesting the existence of both host-generalist and genus-specific lineages of Zanclea associated with scleractinians. In addition to Z. gallii living in association with the genus Acropora, we discovered four well-supported lineages (Clades I, II, III, and VII), each one forming a strict association with a single scleractinian genus, including sequences of Zanclea associated with Montipora from two geographically separated areas (Maldives and Taiwan). Two host-generalist Zanclea lineages were also observed, and one of them was formed by Zanclea specimens symbiotic with seven scleractinian genera (Clade VIII). We also found that the COI gene allows the recognition of separated hidden lineages in agreement with the commonly recommended mitochondrial 16S as a DNA barcoding gene for Hydrozoa and shows reasonable potential for phylogenetic and evolutionary analyses in the genus Zanclea. Finally, as no DNA sequences are available for the majority of the nominal Zanclea species known, we note that they will be necessary to elucidate the diversity of the Zanclea-scleractinian association
Dreams of Molecular Beams: Indium Gallium Arsenide Tensile-Strained Quantum Dots and Advances Towards Dynamic Quantum Dots (Moleculare Radiorum Somnia: Indii Gallii Arsenicus Tensa Quanta Puncta et ad Dinamicae Quantae Puntae Progressus)
No full textThrough the operation of a molecular beam epitaxy (MBE) machine, I worked on developing the homoepitaxy of high quality InAs with a (111)A crystallographic orientation. By tuning substrate temperature, we obtained a transition from a 2D island growth mode to step- ow growth. Optimized MBE parameters (substrate temperature = 500 °C, growth rate = 0.12 ML/s and V/III ratio ⩾ 40) lead to growth of extremely smooth InAs(111)A films, free from hillocks and other 3D surface imperfections. We see a correlation between InAs surface smoothness and optical quality, as measured by photoluminescence spectroscopy. This work establishes InAs(111)A as a platform for future research into other materials from the 6.1 Å family of semiconductors grown with a (111) orientation.
Continuing this work, we also have determined a reproducible set of growth conditions for the self-assembly of tensile-strained In1-xGaxAs quantum dot nanostructures on InAs(111)A surfaces. During molecular beam epitaxy, In1-xGaxAs islands form spontaneously on InAs(111)A when the Ga content x ≥ 50 %. We analyze the structure and composition of InGaAs/InAs(111) samples using atomic force microscopy, transmission electron microscopy, electron energy loss spectroscopy, and photoluminescence spectroscopy. We demonstrate control over the size and areal density of the islands as a function of In1-xGaxAs coverage, In1-xGaxAs composition, and substrate temperature.
Furthermore, we also present a study aimed to determining the growth conditions of In1-xGaxAs self-assembled tensile-strained QDs on GaSb(111)A surfaces. From previous work we determined that a larger band gap barrier was necessary to ensure the confinement of charge carriers in the InGaAs nanostructures. Through a series of temperature, V/III ratio, and growth rate we determined the best parameters for GaSb(111) homoepitaxy. We then studied the nucleation of optimal-morphology In1-xGaxAsQDs by locking the compositions at In0.5Ga0.5As, studying the critical pause for group V element transition and V/III ratio prior and post QD growth. Several photoluminescence techniques are employed to determine the light emission properties of these structures.
Finally, we did preliminary studies on how to achieve the dynamic lateral confinement of charge carriers in 2D and 3D using near-THz surface acoustic phonon pulses in polar semiconductors. Using the acousto-electrical effect, we measure the degree to which surface acoustic waves (SAWs) confine electrons and holes limiting the number of recombination processes. Applications for this technological development include the external modulation of lateral confinement size in the SAWs and subsequent photon emission wavelength, as well as potential quantum logical gate design using acoustic pulses to drive electrons in a circuit
Aplicação das técnicas de espectroscopia de infravermelho com transformada de Fourier (FTIR) nos intervalos médio (MIR) e próximo (NIR), para avaliação do conteúdo em nalcanos e álcoois de cadeia longa de amostras vegetais e fecais
No full textDissertação de Mestrado de Engenharia ZootécnicaO conhecimento dos fatores que influenciam a relação dinâmica entre o animal e a pastagem, em especial o comportamento alimentar dos animais revela-se fundamental para o desenvolvimento de estratégias adequadas de gestão dos herbívoros em pastoreio. Os nalcanos e os álcoois de cadeia longa (LCOH) têm sido utilizados como marcadores fecais para estimar diversos parâmetros nutricionais. No entanto, as suas análises químicas são morosas e dispendiosas, existindo, desta forma, a necessidade de se desenvolverem metodologias mais expeditas para avaliar as concentrações destes marcadores. Este trabalho teve como objetivo avaliar a utilização da tecnologia de Espectroscopia de Infravermelho com Transformada de Fourier (FTIR), no intervalo do infravermelho próximo (NIR) e no intervalo do infravermelho médio (MIR), para a determinação da concentração em n-alcanos e LCOH em amostras de distintas espécies vegetais e amostras fecais de herbívoros domésticos. Nesse sentido, foram registados, através destas técnicas, espectros de 33 amostras de alimentos (Trifolium repens, Erica spp., Lolium perenne, Ulex gallii, herbáceas, herbáceas do monte e gramíneas) e 181 amostras de fezes (bovinos e equinos). De modo a desenvolver calibrações para a previsão de concentrações n-alcanos e LCOH recorreu-se à análise estatística multivariada. Relativamente aos modelos desenvolvidos para as amostras vegetais, os melhores resultados foram observados para as calibrações com recurso ao NIR. Os melhores coeficientes de determinação de validação externa (R 2 v) obtidos foram de 0,90 e 0,79 para LCOH e nalcanos, respetivamente. Para as amostras fecais, no intervalo NIR, os resultados indicam previsões na validação externa (R 2 v) similares para as duas espécies (0,64). Pelo contrário, no intervalo MIR foram observadas diferenças de R 2 v entre amostras fecais de bovinos (0,70) e equinos (0,57). Em relação aos modelos criados para as fezes de ambas as espécies animais, observámos uma tendência para os LCOH e os n-alcanos presentes em maiores concentrações, serem os marcadores com melhores estimativas. Os resultados obtidos neste estudo sugerem que a seleção da técnica a utilizar poderá depender do tipo de matriz, sendo a homogeneidade das matrizes um dos fatores mais importantes para o seu sucesso. No sentido de melhorar a precisão e robustez dos modelos criados para as estimativas das concentrações destes marcadores utilizando estas metodologias, a base de dados (maior variabilidade) utilizada para as calibrações destes modelos terá que ser obrigatoriamente aumentada.Understanding the factors that influence the dynamic relationship between animal and pasture, especially the grazing behaviour of the animals, is fundamental for the development of adequate management strategies of grazing herbivores. N-alkanes and long chain alcohols (LCOH) have been used as faecal markers to estimate various nutritional parameters. However, their chemical analyses are time-consuming and expensive, making it necessary to develop more expeditious methodologies to evaluate the concentrations of these markers. The objective of this work was to evaluate the use of Fourier Transform Infrared Spectroscopy (FTIR) technology in the near infrared (NIR) and mid-infrared (MIR) intervals, for the determination of the concentration of n-alkanes and LCOH, in samples of different plant species and faecal samples of domestic herbivores. In this sense, spectra of 33 food samples (Trifolium repens, Erica spp., Lolium perenne, Ulex gallii, herbaceous, grass herbaceous and grass) and 181 faecal samples (bovine and equine) were recorded using these techniques. In order to develop calibrations for the prediction of n-alkane concentrations and LCOH, a multivariate statistical analysis was used. Regarding the models developed for the plant samples, the best results were observed for the calibrations using the NIR. The best external validation determination coefficients (R 2 v) obtained were 0,90 and 0,79 for LCOH and nalkanes, respectively. For faecal samples, in the NIR range, the results indicate similar external validation predictions (R 2 v) for both species (0,64). However, in the MIR interval, differences of R 2 v were observed between faecal samples of cattle (0,70) and equines (0,57). Relative to the models developed for faeces of both animal species, it was observed that LCOH and n-alkanes presented in higher concentrations, were the markers with the best estimates. The results obtained in this study suggest that the selection of the used technique may depend on the type of matrix, and the homogeneity of the matrices is one of the most important factors for its success. In order to improve the accuracy and robustness of the created models, the database (greater variability) used for the calibrations of these models will have to be increased for the assessment of the concentrations of these markers using these methodologies
Aplicação das técnicas de espectroscopia de infravermelho com transformada de Fourier (FTIR) nos intervalos médio (MIR) e próximo (NIR), para avaliação do conteúdo em nalcanos e álcoois de cadeia longa de amostras vegetais e fecais
No full textDissertação de Mestrado de Engenharia ZootécnicaO conhecimento dos fatores que influenciam a relação dinâmica entre o animal e a pastagem, em especial o comportamento alimentar dos animais revela-se fundamental para o desenvolvimento de estratégias adequadas de gestão dos herbívoros em pastoreio. Os nalcanos e os álcoois de cadeia longa (LCOH) têm sido utilizados como marcadores fecais para estimar diversos parâmetros nutricionais. No entanto, as suas análises químicas são morosas e dispendiosas, existindo, desta forma, a necessidade de se desenvolverem metodologias mais expeditas para avaliar as concentrações destes marcadores. Este trabalho teve como objetivo avaliar a utilização da tecnologia de Espectroscopia de Infravermelho com Transformada de Fourier (FTIR), no intervalo do infravermelho próximo (NIR) e no intervalo do infravermelho médio (MIR), para a determinação da concentração em n-alcanos e LCOH em amostras de distintas espécies vegetais e amostras fecais de herbívoros domésticos. Nesse sentido, foram registados, através destas técnicas, espectros de 33 amostras de alimentos (Trifolium repens, Erica spp., Lolium perenne, Ulex gallii, herbáceas, herbáceas do monte e gramíneas) e 181 amostras de fezes (bovinos e equinos). De modo a desenvolver calibrações para a previsão de concentrações n-alcanos e LCOH recorreu-se à análise estatística multivariada. Relativamente aos modelos desenvolvidos para as amostras vegetais, os melhores resultados foram observados para as calibrações com recurso ao NIR. Os melhores coeficientes de determinação de validação externa (R 2 v) obtidos foram de 0,90 e 0,79 para LCOH e nalcanos, respetivamente. Para as amostras fecais, no intervalo NIR, os resultados indicam previsões na validação externa (R 2 v) similares para as duas espécies (0,64). Pelo contrário, no intervalo MIR foram observadas diferenças de R 2 v entre amostras fecais de bovinos (0,70) e equinos (0,57). Em relação aos modelos criados para as fezes de ambas as espécies animais, observámos uma tendência para os LCOH e os n-alcanos presentes em maiores concentrações, serem os marcadores com melhores estimativas. Os resultados obtidos neste estudo sugerem que a seleção da técnica a utilizar poderá depender do tipo de matriz, sendo a homogeneidade das matrizes um dos fatores mais importantes para o seu sucesso. No sentido de melhorar a precisão e robustez dos modelos criados para as estimativas das concentrações destes marcadores utilizando estas metodologias, a base de dados (maior variabilidade) utilizada para as calibrações destes modelos terá que ser obrigatoriamente aumentada.Understanding the factors that influence the dynamic relationship between animal and pasture, especially the grazing behaviour of the animals, is fundamental for the development of adequate management strategies of grazing herbivores. N-alkanes and long chain alcohols (LCOH) have been used as faecal markers to estimate various nutritional parameters. However, their chemical analyses are time-consuming and expensive, making it necessary to develop more expeditious methodologies to evaluate the concentrations of these markers. The objective of this work was to evaluate the use of Fourier Transform Infrared Spectroscopy (FTIR) technology in the near infrared (NIR) and mid-infrared (MIR) intervals, for the determination of the concentration of n-alkanes and LCOH, in samples of different plant species and faecal samples of domestic herbivores. In this sense, spectra of 33 food samples (Trifolium repens, Erica spp., Lolium perenne, Ulex gallii, herbaceous, grass herbaceous and grass) and 181 faecal samples (bovine and equine) were recorded using these techniques. In order to develop calibrations for the prediction of n-alkane concentrations and LCOH, a multivariate statistical analysis was used. Regarding the models developed for the plant samples, the best results were observed for the calibrations using the NIR. The best external validation determination coefficients (R 2 v) obtained were 0,90 and 0,79 for LCOH and nalkanes, respectively. For faecal samples, in the NIR range, the results indicate similar external validation predictions (R 2 v) for both species (0,64). However, in the MIR interval, differences of R 2 v were observed between faecal samples of cattle (0,70) and equines (0,57). Relative to the models developed for faeces of both animal species, it was observed that LCOH and n-alkanes presented in higher concentrations, were the markers with the best estimates. The results obtained in this study suggest that the selection of the used technique may depend on the type of matrix, and the homogeneity of the matrices is one of the most important factors for its success. In order to improve the accuracy and robustness of the created models, the database (greater variability) used for the calibrations of these models will have to be increased for the assessment of the concentrations of these markers using these methodologies
Generalities in the growth, allocation and leaf quality responses to elevated CO2 in eight woody species
No full textThis paper reports general patterns of relative growth rate and related traits in response to elevated atmospheric CO2 in eight woody species ranging widely in life form, leaf habit, taxonomy and ecology. Young plants of these species, all of comparable ontogenetic phases, were grown simultaneously in large containers with favourable nutrient and water availability in transparent outdoor chambers at 350 and 700 μl l-1 CO2 for one growing season. We found the following consistent responses. (1) All species grew faster at elevated CO2, whereas the following leaf and allocation traits were consistently lower in CO2-enriched environments: specific leaf area (quotient of leaf area and leaf weight), leaf area ratio (quotient of total leaf area and plant weight), weight-based foliar N concentration and, to a smaller extent, leaf weight fraction (quotient of leaf weight and plant weight). (2) There was important interspecific variation in the magnitude of the response of relative growth rate to CO2. Specific leaf area at ambient CO2 explained 88% of the variation in relative growth rate response to CO2 among the eight species. At ambient CO2, relative growth rate itself, was significantly correlated with the relative growth rate response to CO2 only if the leafless species Ulex gallii was excluded from analysis. (3) The four deciduous species had a significantly stronger relative growth rate response to CO2 than the four evergreens. This corresponded with their generally higher specific leaf area. (4) Specific leaf area and leaf habit might be useful for scaling up exercises, as easy-to-measure substitutes for growth responses of (woody) vegetation to elevated CO2. However, the usefulness of such traits in this context needs to be tested in realistic, longer-term manipulative experiments in real ecosystems
Comparison of long-chain fatty acids and alkanes as markers to estimate diet composition of equines and cattle consuming heathland vegetation species
No full textThis study aimed to evaluate the application of long-chain fatty acids (LCFA) as analternative or as a
complement to alkanes to estimate diet composition in equines and cattle. Twelve mature
crossbreedmares (385±47 kg liveweight – LW) and6 adult non-lactating cows (499±36 kg LW)
of Asturiana de los Valles breedwere divided in groups of 3 animals and housed in individual stalls.
Animals received a daily total amount of 1.0 kg DM/100 kg LW of different diets composed of
herbaceous (Lolium perenne) and woody species (Ulex gallii and heather). Diet composition was
estimated from LCFA (i.e., C22–C34) and alkane (i.e., C25–C31 and C33) concentrations in diet and
faeces by least-squares procedures, usingmarker faecal concentrations uncorrected for incomplete
faecal recovery (FC0), corrected usingmean recovery rate of the dietary treatment that the animal
belonged to (FC1), or corrected usingmean recovery rate across all experimental diets (FC2). For all
diet components, LCFA concentrations were higher than the alkane ones, with even-chain LCFA
accounting for more than 0.80 of total LCFA. In general, faecal recovery (FR) of the markers was
incomplete and related to their carbon-chain length. In equines, the FR of both markers tended to
decrease with carbon-chain length in a curvilinear fashion (Pb0.001), whereas in cattle LCFA and
alkane FR tended to increase with carbon-chain length in a curvilinear (Pb0.001) and linear
(Pb0.001) fashion, respectively. Diet composition had an effect (Pb0.001) on the LCFA and alkane
FR in both animal species, and, in equines, seemed to be relatedwith diet digestibility, i.e., decrease
of marker disappearance from the digestive tract with a decrease of diet digestibility. In general,
diet composition estimates based on LCFA alone were more accurate than those obtained using
alkanes alone. Combination of LCFA and alkane markers resulted in an increase (Pb0.05) in the
accuracy of diet estimates in both animal species, indicating a higher discriminatory power among
plant species. The use of FC0 and FC2 resulted in theworst (Pb0.05) estimates of diet composition,
while high levels of accuracy were observed when using more accurate faecal corrections (FC1).
Results showed that LCFA can be useful markers for studying diet selection of equines and cattle
grazing on heathland vegetation communities, if a proper adjustment of their faecal concentrations
prior to their application is applied. It is also concluded that use of LCFA in combination with
alkanes can increase the accuracy of diet composition estimates
