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The high-resolution infrared spectrum of CHD279Br has been investigated by Fourier transform spectroscopy in the range 540–615 cm−1 at an unapodised resolution of 0.0035 cm−1. This spectral region is characterised by the ν6 fundamental (584.8510 cm−1), corresponding to C–Br stretching mode, and its hot band 2ν6−ν6 (578.4333 cm−1). The spectral analysis resulted in the identification of 3430 transitions (J' ≤ 73 and K'a ≤ 18) for the ν6 fundamental and 1212 transitions (J' ≤ 49 and K'a ≤ 11) for the hot band 2ν6−ν6. The assigned data have been fitted using the Watson's S-reduced Hamiltonian in the Ir representation and new constants for the ground state from about 24,600 combination differences and sets of parameters for the v6 = 1 and 2 vibrational states have been obtained. From spectral simulations the intensity ratio between 2ν6−ν6 and ν6 has been estimated to be 0.15 ± 0.02. High-quality ab initio calculations have also been performed at the CCSD(T) level of theory in order to support the experimental investigation through the calculation of molecular parameters relevant to ro-vibrational spectroscopy. [ABSTRACT FROM AUTHOR]

The high-resolution infrared spectrum of CHD279Br has been investigated by Fourier transform spectroscopy in the range 700–900 cm−1 at an unapodized resolution of 0.0035 cm−1. This spectral region is characterised by the absorptions of the ν5 (814.5185 cm−1) and ν9 (716.9649 cm−1) fundamental bands, corresponding to H–C–Br deformation and CD2 rocking modes, respectively. The ν5 vibration of symmetry species A′ gives rise to an a-/c-hybrid band with a predominant a-type component, while the ν9 mode of A′′ symmetry produces a b-type envelope. The spectral analysis resulted in the identification of 5290 (J′ ≤ 63 and Ka′ ≤ 13) and 1657 (J′ ≤ 53 and Ka′ ≤ 12) transitions for ν5 and ν9 bands, respectively. The assigned data were fitted using the Watson's S-reduced Hamiltonian in the Ir representation and the v5 = 1 and v9 = 1 state parameters up to the quartic centrifugal distortion terms have been obtained. From spectral simulations the dipole moment ratio |Δμa/Δμc| of the ν5 band has been determined to be 1.4 ± 0.1 while the intensity ratio between ν5 and ν9 fundamentals has been estimated to have a value of 4.3 ± 0.5. [ABSTRACT FROM AUTHOR]

Water temperature directly affects life cycles, reproductive periods, and metabolism of organisms living the oceans, especially in the surface zones. Due to the ocean warming, changes in water stratification and primary productivity are affecting trophic chains in sensitive world areas, such as the Mediterranean Sea. Benthic and pelagic cnidarians exhibit complex responses to climatic conditions. For example, the structure and phenology of the Mediterranean hydrozoan community displayed marked changes in species composition, bathymetric distribution, and reproductive timing over the last decades. The regional species pool remained stable in terms of species numbers but not in terms of species identity. When the Scyphozoa group is considered, we observe that Pelagia noctiluca (among the most abundant jellyfish in the Mediterranean Sea and eastern Atlantic waters) has increasingly frequent massive outbreaks associated to warmer winters. Variations in metabolic activities, such as respiration and excretion, are strongly temperature-dependent, with direct increment of energetic costs with jellyfish size and temperature, leading to growth rate reduction. Water temperature affects sexual reproduction through changes in the energy storage and gonad development cycles. Anthozoan life cycles depend also on primary productivity and temperature: gonadal production and spawning are tightly related in shallow populations (0–30 m depth) with the spring-summer temperature trends and autumn food availability. Overall, the energy transferred from the mother colonies to the offspring may decrease, negatively affecting their potential to settle, metamorphose and feed during the first months of their lives, eventually impairing the dominance of long-living cnidarian suspension feeders in shallow benthic habitats. In this review, we describe the already ongoing effects of sea warming on several features of cnidarian reproduction, trying to elucidate how reproductive traits and potential dispersion will be affected by the cascade effects of increasing temperature in the Mediterranean Sea. [ABSTRACT FROM AUTHOR]

The patchy distribution pattern of benthic hydrozoans reflects high sensitivity of colonies to local and micro-scale environmental factors, which may affect the outcome of biodiversity inventories based on different sampling methodologies. We compared three quantitative sampling methods for benthic hydrozoans, differing for strategy (scraping standardized surfaces or picking visually located colonies) and tactics (extension of examined surface). Each of the three methods consisted of eight replicate samplings to compare relative and absolute method efficiencies, also in terms of minimum sampling area representative of the hydroid diversity in the study site. A single horizontal belt transect on a vertical rocky cliff was chosen at 15 m depth near Otranto (South Adriatic). A total of 37 species were identified by the three methods and their relative abundances were evaluated. The hydroid assemblage was dominated by generalist species with high polyp numbers able to colonize different substrata. We compared the outcomes of each of the three sampling methods, and by a cost-benefit analysis we identified the optimal sampling methods to be adopted according to the different targets of the investigations. On data standardized to the same total sampled areas, the three sampling methods did not originate significant differences in the number of polyps of each recorded species (PDA, Polyp Detection Ability), whereas the visually-oriented collection (VIS) and the scrapings over 20 × 20 cm standard surfaces (S20) were more effective in the detected number of species (SDA, Species Detection Ability) than over 10 × 10 cm squares (S10). For ecological purposes, samplings based on five S20 replicates can be considered an appropriate experimental design to get a statistically robust representation of the studied hydroid assemblage at Punta Palascia. However, variation in depth, exposure and geographical locations may require different sampling approaches, and pre-surveys should be always carried out before addressing taxonomical surveys of sessile organisms. [ABSTRACT FROM PUBLISHER]