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Tourists approaching wild animals can potentially cause disturbance as a result of the perceived predation risk. Risk effects arise when prey alter their behaviour in response to predators. This response may carry costs through its impact on fitness-related activities such as foraging. We recorded behavioural responses of whale sharks Rhincodon typus to experimental vessel and swimmer approaches. We simulated the disturbance caused by ecotourism in the foraging site of this planktivorous fish in Bahia de Los Angeles, Gulf of Baja California, Mexico. Stress-related behaviours (vigilance, change of direction, diving and acceleration) were more common directly after both types of disturbance than before, in particular after approach by a swimmer. Individuals were more likely to be vigilant when they were new to the bay, but we did not find evidence of within-season behavioural habituation. Sharks were 24% more likely to forage before human stimuli than after. Our study highlights negative effects of vessel and swimmer approaches on whale shark behaviour, with a short-term increase in stress-related behaviours potentially carrying energetic costs, combined with a decrease in food intake following the disturbance. Our results indicate concerns about the impact of ecotourism on large fish species. An important next step would be to determine whether these short-term behavioural responses to the perception of predation risk negatively affect fitness. Among other guidelines, we recommend preventing swimmers from approaching if whale sharks stop feeding when a vessel approaches.
Mirabegron, (C21H24N4O2S), is a β3-adrenoceptor agonist approved in Japan, the USA, Canada and Europe, for the treatment of overactive bladder symptoms. There are no entries for this important active pharmaceutical ingredient in the Cambridge Structural Database or the Powder Diffraction File-4/Organics database. In this contribution, the powder diffraction pattern of Mirabegron, an unreported phase, are presented with a study by spectroscopy methods (Fourier-transform infrared spectroscopy [FT-IR] and RAMAN) and thermal analysis (thermogravimetric analysis [TGA]-differential scanning calorimetry [DSC]).
Alpha lipoic acid (ALA) C8H14O2S2 is a naturally occurring compound that is synthesized in small amounts by plants and animals, including humans. ALA is covalently bound to specific proteins, which function as cofactors for several important mitochondrial enzyme complexes and studies suggest that they might help with type 2 diabetes. In the Cambridge Structural Database, there are four entries related to this compound: two for lipoic acid and two for complexes. In the Powder Diffraction File-4, two experimental unindexed patterns are reported. The material crystallizes in a monoclinic crystal system, space group P21/a and cell parameters a = 9.237 (1) Å, b = 9.960 (1) Å, c = 11.787 (2) Å, β = 109.13 (1)°, and V = 1024.6 (2) Å3.
The title compound, the 4-phenyl-6-(trifluoromethyl)-3,4-dihydroquinolin-2(1H)-one (4) with chemical formula: (C16H12F3NO), was synthesized from N-[4-(trifluoromethyl)phenyl]cinnamamide (3), chemical formula: (C16H12F3NO), through an intramolecular cyclization mediated by triflic acid. Preliminary molecular characterization of both compounds was performed by Fourier transform infrared spectroscopy, gas chromatography mass spectrometry, and nuclear magnetic resonance spectroscopy (1H, 13C); crystallographic characterization was completed by X-ray diffraction of polycrystalline samples. The title compound 4 crystallized in a monoclinic system and unit-cell parameters are reported [a = 16.002 (3), b = 5.170 (1), c = 17.733 (3) Å, β = 111.11 (2)°, unit-cell volume V = 1368.5 (3) Å3, Z = 4] P21/c (No. 14) space group; the title compound 3 crystallized in a monoclinic system and unit-cell parameters are reported [a = 12.902 (2), b = 5.144 (1), c = 20.513 (5) Å, β = 91.67 (2)°, unit-cell volume V = 1360.7 (4) Å3, Z = 4] P21/c (No. 14) space group.
The α-aminonitrile, 2-morpholino-2-(3,4,5-trimethoxyphenyl)acetonitrile (C15H20N2O4), was prepared through a silica sulfuric acid-catalyzed Strecker reaction between 3,4,5-trimethoxybenzaldehyde, morpholine, and two different cyanide sources. Molecular characterization was performed by Fourier transform infrared spectroscopy, gas chromatography–mass spectrometry, (1H, 13C – mono and bidimensional) nuclear magnetic resonance; crystallographic characterization was completed by X-ray powder diffraction of polycrystalline samples. The title compounds crystallized in a monoclinic system and unit-cell parameters are reported [a = 13.904(2), b = 5.1696(6), c = 21.628(3) Å, β = 104.31(1)°, unit-cell volume V = 1506.3(3) Å3, Z = 4]. All measured lines were indexed with the P21/a (No. 14) space group.
Rocks are composed of minerals, bounding matrix, cracks and pores. The study of changes in the physical properties of rocks as a function of heat treatment is relevant to various engineering and industrial applications. The effect of thermal damage on the compression, strength, ultimate compression strain, color and loss of mass of two different limestones extracted from the Yucatan Peninsula is studied. Different thermal treatments are applied by heating the sample from room temperature up to 600°C, with steps of 100°C. The results show a high correlation between the heat transport characteristics, mechanical properties, content of organic matter and the presence of carbonates and iron oxides in each type of limestone rock.
In this study electrochemical and surface analysis were carried out in order to provide preliminary information to diagnose the state of conservation of two bronze bells from two Colonial religious building from San Francisco de Campeche City: The Cathedral of Nuestra Señora de la Purísima Concepción and the Ex-temple of San José. Small corroded bronze samples were retired from each bell and analyzed by using optical microscopy in order to observe the distribution of the oxides over metal surface. Complementary XRD analysis was used to identify crystalline phases formed as a consequence of bells interaction with the urban tropical environment of this city. Electrochemical techniques such as linear polarization resistance (Rp) and potentiodynamic curve (CP) were conducted “in situ” in order to evaluate the behavior of bell bronze patinas under the action of two artificial solutions that recreate typical electrolyte formed over corroded metal surfaces in urban environments.
The 4-benzyloxy-1-oxaspiro-[4.6]-undec-3-en-2-one (C17H20O3) was prepared through a domino reaction from benzyl α-hydroxycycloheptanecarboxylate and the cumulated ylide Ph3P=C=C=O by: (i) addition and (ii) intramolecular Wittig Olefination reaction. The reaction was carried out using anhydrous toluene as solvent under an argon atmosphere in a Schlenk flask. Molecular characterization was performed by Fourier transform infrared spectroscopy, gas chromatography-mass spectrometry, (1H,13C – mono and bidimensional) nuclear magnetic resonance spectroscopy; crystallographic characterization was completed by X-ray diffraction of polycrystalline samples (XRPD). The title compound crystallized in a monoclinical system and unit-cell parameters are reported [a = 13.207(3) Å, b = 5.972(1) Å, c = 19.719(4) Å, β = 105.67(2)°, unit-cell volume V = 1497.5 (4) Å3, Z = 4]. All of the measured lines were indexed with the P21/n (No. 14) space group.
We present new results of our wide-field redshift survey of galaxies in a 182 square degree region of the Shapley Supercluster (SSC) based on observations with the FLAIR-II spectrograph on the UK Schmidt Telescope (UKST). In this paper we present new measurements to give a total sample of redshifts for 710 bright (R ≤ 16.6) galaxies, of which 464 are members of the SSC (8000 < v < 18 000 km s–1). Our data reveal that the main plane of the SSC (v ≈ 14 500 km s–1) extends further than previously realised, filling the whole extent of our survey region of 10 degrees by 20 degrees on the sky (35 Mpc by 70 Mpc, for H0 = 75 km s–1 Mpc–1). There is also a significant structure associated with the slightly nearer Abell 3571 cluster complex (v ≈ 12 000 km s–1) with a caustic structure evident out to a radius of 6 Mpc. These galaxies seem to link two previously identified sheets of galaxies and establish a connection with a third one at V (V) = 15 000 km s–1 near RA = 13h. They also tend to fill the gap of galaxies between the foreground Hydra-Centaurus region and the more distant SSC. We calculate galaxy overdensities of 5.0 ± 0.1 over the 182 square degree region surveyed and 3.3 ± 0.1 in a 159 square degree region excluding rich clusters. Over the large region of our survey the inter-cluster galaxies make up 46 per cent of all galaxies in the SSC region and may contribute a similar amount of mass to the cluster galaxies.
We present new radial velocities for 306 bright (R < 16) galaxies in a 77 deg2 region of the Shapley supercluster, measured with the FLAIR-II spectrograph on the UK Schmidt Telescope. The galaxies we measured were uniformly distributed over the survey area, in contrast to previous samples which were concentrated in several rich Abell clusters. Most of the galaxies (230) were members of the Shapley supercluster: they trace out two previously unknown sheets of galaxies linking the Abell clusters of the supercluster. In a 44 deg2 area of the supercluster excluding the Abell clusters, these sheets alone represent an overdensity of a factor of 2·0 ± 0·2 compared to a uniform galaxy distribution. The supercluster is not flattened in the Declination direction as has been suggested in previous papers. Within our survey area the new galaxies contribute an additional 50% to the known contents of the Shapley supercluster, with a corresponding increase in its contribution to the motion of the Local Group.
The Dusky-legged Guan Penelope obscura is the southernmost species of the family Cracidae, reaching its southern distributional limit in the delta of the Paraná River. Habitat loss, together with uncontrolled harvest, has led to local-scale decreases or extirpation of the species, but no quantitative evaluation of habitat preferences has been made. We surveyed Dusky-legged Guans in the Delta del Paraná Biosphere Reserve, Argentina, by motorboat along 543.9 km of nine waterways during both January and July 2009 and used occupancy modelling to estimate habitat and seasonal effects on occupancy. Detectability was 21–22% on average and occupancy estimates were highly variable within habitats, but highest in secondary forest, followed by mature plantation, and lowest in occupied residences. There were no significant differences in occupancy or detectability among habitats or seasonally. There was a strong positive effect of length of riparian habitat segments on occupancy and detectability. Habitat management efforts should address increasing the suitability of mature plantation forest for guans by increasing their similarity to native forest in structure and composition. Furthermore, we illustrate that surveys by boat can be logistically effective for surveying cracids associated with riverine habitats and that it is important to account for incomplete detectability since in our case failing to do so would have underestimated occupancy by 78–79% on average. Given this, the use of commonly accepted methodologies for surveying cracids that do not account for incomplete detectability should be reconsidered and methodologies that can produce robust, reliable estimates applied.
Knowledge of the mechanical and petrographic properties of limestone rocks is an important issue to different areas of science and engineering. Sedimentary limestone rock is one of the most abundant materials in the Peninsula of Yucatán used for decorative and building construction. This work studies the petrographic, mineralogical, and physical properties of three different types of limestone slabs of the state of Yucatán.
Fourier Transform infrared spectroscopy has been employed to study the shells of two kind of mollusks, American oysters (Crassostrea virginica) and mussels (Ischadium recurvum). It is shown that it is possible to distinguish the different calcium carbonate lattice vibrations in each case, mussel shells present aragonite vibration frequencies, and the oyster shells present those corresponding to calcite. The superposition, shift and broadening of the infrared bands are discussed. Changes in the vibration modes due to successive thermal treatments are also reported.
Most of the inorganic biomineralized materials are deposited on an organic matrix that controls the orientation and structure of the crystals. It is thought that chemical groups at the surface of the matrix may act as a template for the nucleation and growth of the mineral. A x-ray diffraction study of the texturization development of the bivalve mollusk shells is presented; specifically, the mussel Ischadium recurvum (Rafinesque, 1820), in different growing stages. The x-ray reflections show a preferred orientation that changes as the mollusk grows, and at the final stages only two crystallographic planes prevail.
The x-ray diffuse scattering pattern from a commercial bulk n-type Hg0.80Cd0.20Te single crystal was measured in absolute units. Anomalous dispersion techniques near the Hg LIII edge were used to determine theintensity due to Hg interactions. Diffuse x-ray superlattice reflections are reported that are forbidden by the zinc-blende structure. The systematic absences in these peaks eliminate the possibility that they are the result of a Cu3Au ordering scheme.
Finite element results are presented for the case of an elastically bent isotropic rectangular crystal with clamped boundary conditions. Results show that the anticlastic curvature can be eliminated in the center of the crystal provided the crystal length to width ratio fits a “golden aspect ratio” which is dependent on the Poisson coefficient ν. For ν=0.262 (appropriate for Si(111)), this ratio is approximately equal to 1.42.
Local atomic arrangements in Hg0.80Cd0. 20Te were investigated by measuring the diffuse x-ray scattering at two different energies near the HgLIII absorption edge to yield intensity due only to Hg-Hg, Hg-Te, and Hg-Cd pair interactions. The data were separated into short range order and displacement intensities. Simulation revealed ordered regions with 3:1 Hg-Cd near neighbor configurations. The Hg-Te length is contracted.