The invasion of Lehmann lovegrass (Eragrostis lehmanniana Nees) in rangelands of Chihuahua, Mexico, has resulted in a need for revegetation to recover lost forage productivity. Thus, new knowledge on generating alternatives to improve these invaded grasslands is of great importance. This study evaluated seedbeds prepared with unconventional tillage implements and seeded with a grass mixture to reduce the plant density of E. lehmanniana while increasing the productivity of an invaded semiarid grassland of Chihuahua. The unconventional tillage implements were: a Rangeland Harrow, which was used to prepare the Striped Harrowing and Full Harrowing seedbeds; Rangeland Rehabilitator, which was used to prepare the Deep-Stingray Subsoiler seedbed; and a Tandem-type Aerator Roller, which was used to prepare the Double-Digging Aeration seedbed. An area without tillage was left as a control. The seed mixture was composed of blue grama [Bouteloua gracilis (Willd. ex Kunth) Lag. ex Griffiths var. Hachita] (25%); sideoats grama [Bouteloua curtipendula (Michx.) Torr. ‘6107 Kansas’] (25%); green sprangletop [Leptochloa dubia (Kunth) Nees var. Van Horn] (5%); weeping lovegrass [Eragrostis curvula (Schrad.) Nees var. Ermelo] (40%), and Columbus grass [Sorghum almum Parodi] (5%). The experiment was conducted across 4 yr, and the evaluation started at the second year. Plant density and dry matter (DM) production were evaluated per species. In the control plot, the plant density of E. lehmanniana increased approximately 180% from the 2nd to the 4th year (18 to 50 plants m−2). The use of unconventional tillage implements for seedbed preparation and the inclusion of E. curvula in the seed mixture decreased E. lehmanniana density in more than 50% of plots and increased DM production in around 100% of plots. Considering the whole experimental period, in all the prepared seedbed treatments, E. curvula had the highest establishment and DM production of all the seeded species. The native species B. gracilis, B. curtipendula, and L. dubia had poor establishment in all the prepared seedbeds.

Behavioural plasticity in animals is tested whenever competitive interactions for space and/or food resources occur between wildlife and human activities. This study uses the concepts of operational and non-operational interactions between bottlenose dolphins (Tursiops truncatus) and artisanal fisheries in Alvarado, to search for differences in behaviour, age structure and group size. We conducted 20 surveys between 2015 and 2016, and recorded 64 groups by means of scan sampling from either a research boat or a fixed vantage point. Average dolphin group size was small (${\bar{\rm x}}$ = 3.2, SD = 2.2 individuals) and fewer individuals were commonly present when interaction with fisheries occurred. Operational interactions were defined within the first 30 m and occurred mainly with lone individuals (54% recorded from the lighthouse and 82% during surveys); this benchmark also accounted for higher frequencies in locomotion and feeding (χ2 = 83.10; df = 7; P < 0.001). We found a higher rate of new behavioural events for dolphin groups furthest from human activities, as well as a decrease in behaviours that imply greater body exposure as dolphins approach the fishing spots. Age structure and dolphin group size were not different during and in the absence of interaction with fisheries, but most interactions involved male dolphins. Behavioural variations in the dolphins' repertoire are likely a strategy to reduce the risk of injuries or death when interacting with human activities; these dolphins seem to have habituated to or at least tolerate fishing activities within the study area, possibly constituting a sex-biased pressure.

We provide an expanded and updated, 2-locus phylogeny (mtSSU, nuLSU) of the lichenized fungal family Trypetheliaceae, with a total of 196 ingroup OTUs, in order to further refine generic delimitations and species concepts in this family. As a result, the following 15 clades are recognized as separate genera, including five newly established genera: Aptrootia, Architrypethelium, Astrothelium (including the bulk of corticate species with astrothelioid ascospores; synonyms: Campylothelium, Cryptothelium, Laurera), Bathelium s. str. (excluding B. degenerans and relatives which fall into Astrothelium), the reinstated Bogoriella (for tropical, lichenized species previously placed in Mycomicrothelia), Constrictolumina gen. nov. (for tropical, lichenized species of Arthopyrenia), Dictyomeridium gen. nov. (for a subgroup of species with muriform ascospores previously placed in Polymeridium), Julella (provisionally, as the type species remains unsequenced), Marcelaria (Laurera purpurina complex), Nigrovothelium gen. nov. (for the Trypethelium tropicum group), Novomicrothelia gen. nov. (for an additional species previously placed in Mycomicrothelia), Polymeridium s. str., Pseudopyrenula, Trypethelium s. str. (T. eluteriae group), and Viridothelium gen. nov. (for the Trypethelium virens group). All recognized genera are phenotypically characterized and a discussion on the evolution of phenotypic features in the family is given. Based on the obtained phylogeny, species delimitations are revised and the importance of characters such as thallus morphology, hymenial inspersion, and secondary chemistry for taxonomic purposes is discussed, resulting in a refined species concept.

We present a simple and robust method to acquire quantitative maps of compositional fluctuations in nanostructures from low magnification high-angle annular dark field (HAADF) micrographs calibrated by energy-dispersive X-ray (EDX) spectroscopy in scanning transmission electron microscopy (STEM) mode. We show that a nonuniform background in HAADF-STEM micrographs can be eliminated, to a first approximation, by use of a suitable analytic function. The uncertainty in probe position when collecting an EDX spectrum renders the calibration of HAADF-STEM micrographs indirect, and a statistical approach has been developed to determine the position with confidence. Our analysis procedure, presented in a flowchart to facilitate the successful implementation of the method by users, was applied to discontinuous InGaN/GaN quantum wells in order to obtain quantitative determinations of compositional fluctuations on the nanoscale.

Computational fluid dynamics has been applied to the design, refinement, and assessment of surgical procedures and medical devices. This tool calculates flow patterns and pressure changes within a virtual model of the cardiovascular system. In the field of paediatric cardiac surgery, computational fluid dynamics is being used to elucidate the optimal approach to staged reconstruction of specific defects and study the haemodynamics of the resulting anatomical configurations after reconstructive or palliative surgery. In this paper, we review the techniques and principal findings of computational fluid dynamics studies as applied to a few representative forms of congenital heart disease.

An early and massive settlement of Lepas australis and Lepas pectinata attached to pumice from a recent volcanic eruption is described for the first time. The last 2010 earthquake of central Chile generated stress changes on the magma pathway and this reaction induced the Cordón-Caulle Volcanic Complex eruption on 4 June 2011. Only four months later, a great amount of pumice showing a massive settlement of goose barnacles (Lepas spp.) was drift-carried to the Chilean coast. Our results suggest that the larval attachment structures of Lepas australis and L. pectinata have a high capacity for adhering to the pumice surface, using it as an important dispersion vector.

During a parasitological survey of the brown mussel Perna perna from highly productive culture fields in the southern sector of Brazil, monstrilloid copepods were discovered in the mantle of this mytilid bivalve. Numerous specimens of endoparasitic copepods were found within nodules in the mantle of the host; they belong to an undetermined species of Monstrilla. Monstrilloid copepods were known to be endoparasitic in polychaetes and in one species of prosobranch mollusc only; their occurrence as parasites of bivalve molluscs has not been previously documented. This is also the first record of these crustaceans infecting commercial molluscs. The prevalence of Monstrilla sp. infecting the brown mussel was 25.6%. At the histological level, it was observed that the larvae induced a strong haemocytic infiltration resulting from the complete larval encapsulation within the host mantle. The effect of this monstrilloid in the cultured populations of P. perna deserves further study.

Monstrilloid copepods from a series of zooplankton samples collected in the coastal area of Miami, Florida, were examined taxonomically. Several adult females were found to belong to an undescribed species of Cymbasoma within the C. rigidum species complex. It can be distinguished from its congeners by the body proportions, shape of head, cephalic ornamentation pattern, genital double somite with straight lateral margins, and structure of the fifth legs, which have a small, inner lobe arising from the distal 1/5 of segment. This species shows intraspecific variability in some characters (i.e. shape of head, cephalic and genital ornamentation patterns); hitherto, such variation has been reported only in another species of Cymbasoma. Our finding supports the idea of the nominal species C. rigidum comprising a taxonomic complex with several undescribed taxa. The other species recorded in the area was Cymbasoma quadridens Davis, 1947. This was first described from a single male specimen collected in 1947 in Biscayne Bay, Florida, and has not been recorded thereafter. The type specimen now being unusable, this species is redescribed herein based on another topotypic male specimen collected near the type locality. New data are added about the armature of its antennules and swimming legs, cuticular ornamentation, and structure of the genital complex.

The tanaidaceans are among the most conspicuous and ecologically relevant benthic microcrustaceans in the marine realm but there are only a few records of species of tanaids associated with other marine organisms. During a long-term survey on the biology and distribution of the Caribbean manatee Trichechus manatus manatus Linnaeus in Mexican waters, parasites and epibionts were collected from 47 individuals that were captured for tagging in two bay systems. Well-established epibiotic communities of the tanaidacean Hexapleomera robusta (Moore) were found on eight of these animals; this tanaid crustacean formed patches of tubes adhered to the skin surface. Patches were distributed in different parts of the body surface but mainly along the backbone depression, the caudal zone, and on the lateral margins; in some instances they were related to clusters of barnacles. Highly significant differences of infestation rates were revealed between Chetumal Bay and Ascensión Bay, the latter representing better conditions (high salinity and hydrodynamism) for tanaid invasion and settlement on the manatee. It is speculated that the tanaid is a commensal; no visible damage was found in the host and its presence was not related to skin lesions. The tanaid probably captures suspended particles as the manatee feeds. This is the first confirmed record of a symbiotic association involving a tanaid and the Caribbean manatee. The tanaid species recorded (H. robusta) and the harpacticoid copepod Balaenophilus manatorum (Ortíz, Lalana & Torres), have both been recorded also as epibionts of sea turtles. The tanaid has been known from sea turtles for some time, but the copepod was first recorded from a manatee and was subsequently found on sea turtles a few years later.

Developing a standardized survey methodology to census and estimate the size of wintering populations is a main conservation priority for the endangered Little Bustard. We present a standard and repeatable methodology to census wintering Little Bustard populations at a regional scale, and the first statistically reliable population estimate of a Little Bustard wintering population in Spain. We carried out two surveys, in 2003 and 2004, using UTM 10 km × 10 km squares as census units, which were subjected to stratified sampling over the species' potential distribution range in the region of Madrid (Central Spain). Only the areas of potentially suitable habitat within squares of known winter presence of the species were considered. The species' winter distribution in Madrid was fairly constant between years, showing a fragmented pattern in three main nuclei. The number of Little Bustards observed was consistent between surveys (752 and 786 birds, respectively), with birds grouped in an average of 32 flocks (1 to 350 birds, mean = 27.9 birds). No between-winter differences in flock size were observed, although differences between sectors were significant. The highest densities were observed in the Tagus valley (mean density = 2.9 birds km−2, 293 birds), followed by north-eastern farmland (mean density = 0.6 bird km−2, 269 birds). The estimated size of the Little Bustard population wintering in the Madrid region was 1,051 (95% CI = 1,043–1,231). This calculation was based on recorded population density, measured as the number of birds per square kilometre, and considers the potential habitats available in each sector. We propose this methodology as adequate for surveying any Little Bustard wintering area, at both regional and smaller spatial scales. Survey results are consistent with previous tentative estimates for the region of Madrid, and with available information on Little Bustard movements. Sixty-five per cent of squares with Little Bustard presence were outside any protected area, which makes the wintering Little Bustard population of Madrid highly vulnerable to habitat disappearance and may affect the viability of breeding nuclei whose individuals winter in the region.